The modern assembler - Free Essay Example

Sample details Pages: 15 Words: 4404 Downloads: 8 Date added: 2017/06/26 Category Statistics Essay Did you like this example? Q1. Design specification of an assembler with diagram? Ans. Typically a modern assembler creates object code by translating assembly instruction mnemonics into opcodes, and by resolving symbolic names for memory locations and other entities. The use of symbolic references is a key feature of assemblers, saving tedious calculations and manual address updates after program modifications. Most assemblers also include macro facilities for performing textual substitutionà ¢Ã¢â€š ¬Ã¢â‚¬ e.g., to generate common short sequences of instructions to run inline, instead of in a subroutine. Assemblers are generally simpler to write than compilers for high-level languages, and have been available since the 1950s. Modern assemblers, especially for RISC based architectures, such as MIPS, Sun SPARC, and HP PA-RISC, as well as x86(-64), optimize instruction scheduling to exploit the CPU pipeline efficiently. Don’t waste time! Our writers will create an original "The modern assembler" essay for you Create order There are two types of assemblers based on how many passes through the source are needed to produce the executable program. One-pass assemblers go through the source code once and assumes that all symbols will be defined before any instruction that references them. Two-pass assemblers (and multi-pass assemblers) create a table with all unresolved symbols in the first pass, then use the 2nd pass to resolve these addresses. The advantage in one-pass assemblers is speed which is not as important as it once was with advances in computer speed and capabilities. The advantage of the two-pass assembler is that symbols can be defined anywhere in the program source. As a result, the program can be defined in a more logical and meaningful way. This makes two-pass assembler programs easier to read and maintain. More sophisticated high-level assemblers provide language abstractions such as: Advanced control structures High-level procedure/function declarations and invocations High-level abstract data types, including structures/records, unions, classes, and sets Sophisticated macro processing Object-Oriented features such as encapsulation, polymorphism, inheritance, interfaces Note that, in normal professional usage, the term assembler is often used ambiguously: It is frequently used to refer to an assembly language itself, rather than to the assembler utility. Thus: CP/CMS was written in S/360 assembler as opposed to ASM-H was a widely-used S/370 assembler. Assembly language A program written in assembly language consists of a series of instructionsmnemonics that correspond to a stream of executable instructions, when translated by an assembler, that can be loaded into memory and executed. For example, an x86/IA-32 processor can execute the following binary instruction as expressed in machine language: Binary: 10110000 01100001 (Hexadecimal: B0 61) The equivalent assembly language representation is easier to remember (example in Intel syntax, more mnemonic): MOV AL, #61h This instruction means: Move the value 61h (or 97 decimal; the h-suffix means hexadecimal; the hash sign means move the immediate value, not location) into the processor register named AL. The mnemonic mov represents the opcode 1011 which moves the value in the second operand into the register indicated by the first operand. The mnemonic was chosen by the instruction set designer to abbreviate move, making it easier for the programmer to remember. A comma-separated list of arguments or parameters follows the opcode; this is a typical assembly language statement. In practice many programmers drop the word mnemonic and, technically incorrectly, call mov an opcode. When they do this they are referring to the underlying binary code which it represents. To put it another way, a mnemonic such as mov is not an opcode, but as it symbolizes an opcode, one might refer to the opcode mov for example when one intends to refer to the binary opcode it symbolizes rather than to the symbol the mnemonic itself. As few modern programmers have need to be mindful of actually what binary patterns are the opcodes for specific instructions, the distinction has in practice become a bit blurred among programmers but not among processor designers. Transforming assembly into machine language is accomplished by an assembler, and the reverse by a disassembler. Unlike in high-level languages, there is usually a one-to-one correspondence between simple assembly statements and machine language instructions. However, in some cases, an assembler may provide pseudoinstructions which expand into several machine language instructions to provide commonly needed functionality. For example, for a machine that lacks a branch if greater or equal instruction, an assembler may provide a pseudoinstruction that expands to the machines set if less than and branch if zero (on the result of the set instruction). Most full-featured assemblers also provide a rich macro language (discussed below) which is used by vendors and programmers to generate more complex code and data sequences. Each computer architecture and processor architecture has its own machine language. On this level, each instruction is simple enough to be executed using a relatively small number of electronic circuits. Computers differ by the number and type of operations they support. For example, a new 64-bit machine would have different circuitry from a 32-bit machine. They may also have different sizes and numbers of registers, and different representations of data types in storage. While most general-purpose computers are able to carry out essentially the same functionality, the ways they do so differ; the corresponding assembly languages reflect these differences. Multiple sets of mnemonics or assembly-language syntax may exist for a single instruction set, typically instantiated in different assembler programs. In these cases, the most popular one is usually that supplied by the manufacturer and used in its documentation. Language design Basic elements Any Assembly language consists of 3 types of instruction statements which are used to define the program operations: opcode mnemonics data sections assembly directives Opcode mnemonics Instructions (statements) in assembly language are generally very simple, unlike those in high-level languages. Generally, an opcode is a symbolic name for a single executable machine language instruction, and there is at least one opcode mnemonic defined for each machine language instruction. Each instruction typically consists of an operation or opcode plus zero or more operands. Most instructions refer to a single value, or a pair of values. Operands can be either immediate (typically one byte values, coded in the instruction itself) or the addresses of data located elsewhere in storage. This is determined by the underlying processor architecture: the assembler merely reflects how this architecture works. Data sections There are instructions used to define data elements to hold data and variables. They define what type of data, length and alignment of data. These instructions can also define whether the data is available to outside programs (programs assembled separately) or only to the program in which the data section is defined. Assembly directives / pseudo-ops Assembly Directives are instructions that are executed by the Assembler at assembly time, not by the CPU at run time. They can make the assembly of the program dependent on parameters input by the programmer, so that one program can be assembled different ways, perhaps for different applications. They also can be used to manipulate presentation of the program to make it easier for the programmer to read and maintain. (For example, pseudo-ops would be used to reserve storage areas and optionally their initial contents.) The names of pseudo-ops often start with a dot to distinguish them from machine instructions. Some assemblers also support pseudo-instructions, which generate two or more machine instructions. Symbolic assemblers allow programmers to associate arbitrary names (labels or symbols) with memory locations. Usually, every constant and variable is given a name so instructions can reference those locations by name, thus promoting self-documenting code. In executable code, the name of each subroutine is associated with its entry point, so any calls to a subroutine can use its name. Inside subroutines, GOTO destinations are given labels. Some assemblers support local symbols which are lexically distinct from normal symbols (e.g., the use of 10$ as a GOTO destination). Most assemblers provide flexible symbol management, allowing programmers to manage different namespaces, automatically calculate offsets within data structures, and assign labels that refer to literal values or the result of simple computations performed by the assembler. Labels can also be used to initialize constants and variables with relocatable addresses. Assembly languages, like most other computer languages, allow comments to be added to assembly source code that are ignored by the assembler. Good use of comments is even more important with assembly code than with higher-level languages, as the meaning and purpose of a sequence of instructions is harder to decipher from the code itself. Wise use of these facilities can greatly simplify the problems of coding and maintaining low-level code. Raw assembly source code as generated by compilers or disassemblers à ¢Ã¢â€š ¬Ã¢â‚¬  code without any comments, meaningful symbols, or data definitions à ¢Ã¢â€š ¬Ã¢â‚¬  is quite difficult to read when changes must be made. Macros Many assemblers support macros, programmer-defined symbols that stand for some sequence of text lines. This sequence of text lines may include a sequence of instructions, or a sequence of data storage pseudo-ops. Once a macro has been defined using the appropriate pseudo-op, its name may be used in place of a mnemonic. When the assembler processes such a statement, it replaces the statement with the text lines associated with that macro, then processes them just as though they had appeared in the source code file all along (including, in better assemblers, expansion of any macros appearing in the replacement text). Since macros can have short names but expand to several or indeed many lines of code, they can be used to make assembly language programs appear to be much shorter (require less lines of source code from the application programmer as with a higher level language). They can also be used to add higher levels of structure to assembly programs, optionally introduce embedded de-bugging code via parameters and other similar features. Many assemblers have built-in macros for system calls and other special code sequences. Macro assemblers often allow macros to take parameters. Some assemblers include quite sophisticated macro languages, incorporating such high-level language elements as optional parameters, symbolic variables, conditionals, string manipulation, and arithmetic operations, all usable during the execution of a given macros, and allowing macros to save context or exchange information. Thus a macro might generate a large number of assembly language instructions or data definitions, based on the macro arguments. This could be used to generate record-style data structures or unrolled loops, for example, or could generate entire algorithms based on complex parameters. An organization using assembly language that has been heavily extended using such a macro suite can be considered to be working in a higher-level language, since such programmers are not working with a computers lowest-level conceptual elements. Macros were used to customize large scale software systems for specific customers in the mainframe era and were also used by customer personnel to satisfy their employers needs by making specific versions of manufacturer operating systems; this was done, for example, by systems programmers working with IBMs Conversational Monitor System/Virtual Machine (CMS/VM) and with IBMs real time transaction processing add-ons, CICS, Customer Information Control System, and ACP/TPF, the airline/financial system that began in the 1970s and still runs many large Global Distribution Systems (GDS) and credit card systems today. It was also possible to use solely the macro processing capabilities of an assembler to generate code written in completely different languages, for example, to generate a version of a program in Cobol using a pure macro assembler program containing lines of Cobol code inside assembly time operators instructing the assembler to generate arbitrary code. This was because, as was realized in the 1970s, the concept of macro processing is independent of the concept of assembly, the former being in modern terms more word processing, text processing, than generating object code. The concept of macro processing in fact appeared in and appears in the C programming language, which supports preprocessor instructions to set variables, and make conditional tests on their values. Note that unlike certain previous macro processors inside assemblers, the C preprocessor was not Turing-complete because it lacked the ability to either loop or go to, the latter allowing the programmer to loop. Despite the power of macro processing, it fell into disuse in high level languages while remaining a perennial for assemblers. This was because many programmers were rather confused by macro parameter substitution and did not disambiguate macro processing from assembly and execution. Macro parameter substitution is strictly by name: at macro processing time, the value of a parameter is textually substituted for its name. The most famous class of bugs resulting was the use of a parameter that itself was an expression and not a simple name when the macro writer expected a name. In the macro: foo: macro a load a*b the intention was that the caller would provide the name of a variable, and the global variable or constant b would be used to multiply a. If foo is called with the parameter a-c, an unexpected macro expansion occurs. To avoid this, users of macro processors learned to religiously parenthesize formal parameters inside macro definitions, and callers had to do the same to their actual parameters. PL/I and C feature macros, but this facility was underused or dangerous when used because they can only manipulate text. On the other hand, homoiconic languages, such as Lisp, Prolog, and Forth, retain the power of assembly language macros because they are able to manipulate their own code as data. Support for structured programming Some assemblers have incorporated structured programming elements to encode execution flow. The earliest example of this approach was in the Concept-14 macro set, originally proposed by Dr. H.D. Mills (March, 1970), and implemented by Marvin Kessler at IBMs Federal Systems Division, which extended the S/360 macro assembler with IF/ELSE/ENDIF and similar control flow blocks.[3] This was a way to reduce or eliminate the use of GOTO operations in assembly code, one of the main factors causing spaghetti code in assembly language. This approach was widely accepted in the early 80s (the latter days of large-scale assembly language use). A curious design was A-natural, a stream-oriented assembler for 8080/Z80 processors from Whitesmiths Ltd. (developers of the Unix-like Idris operating system, and what was reported to be the first commercial C compiler). The language was classified as an assembler, because it worked with raw machine elements such as opcodes, registers, and memory references; but it incorporated an expression syntax to indicate execution order. Parentheses and other special symbols, along with block-oriented structured programming constructs, controlled the sequence of the generated instructions. A-natural was built as the object language of a C compiler, rather than for hand-coding, but its logical syntax won some fans. There has been little apparent demand for more sophisticated assemblers since the decline of large-scale assembly language development.In spite of that, they are still being developed and applied in cases where resource constraints or peculiarities in the target systems architecture prevent the effective use of higher-level languages.[ Q2. Assembler converts mnemonic code in to machine understandable form? Ans. A simple instruction in assembly language such as add 4 and 5 may look like 00111101001 in machine language . How computer realize which is add instruction and which are numbers in the set of above binary numbers ? actually an instruction like add 4 and 5 would translate into something like MVI R1, 4 MVI R2, 5 ADD R1, R2 in assembly It would then be translated into its sequence of opcodes as 00111100 00111101 01111100 now assume that the electronic circuit of your processor looks at high bits as a high voltage of say 5V and the low bits as 0 V so as soon as the 1st instruction is read (00111100), into memory the relevant electronic voltages are generated and 4 gets stored in Register R1. Similarly 5 gets stored in register R2. The last instruction selects the adder circuit and passes the contents of the two registers to it as input which then outputs the sum which then gets stored in one register as well. Q3. Machine language and Assembly language both are low level languages but still not similar. Give examples? Write a program to display your name using any of machine languages? Ans. In computer science, a low-level programming language is a language that provides little or no abstraction from a computers instruction set architecture. The word low refers to the small or nonexistent amount of abstraction between the language and machine language; because of this, low-level languages are sometimes described as being close to the hardware. A low-level language does not need a compiler or interpreter to run; the processor for which the language was written is able to run the code without using either of these. By comparison, a high-level programming language isolates the execution semantics of a computer architecture from the specification of the program, making the process of developing a program simpler and more understandable. Low-level programming languages are sometimes divided into two categories: first generation, and second generation. First generation The first-generation programming language, or 1GL, is machine code. It is the only language a microprocessor can understand directly. Currently, programmers almost never write programs directly in machine code, because not only does it (like assembly language) require attention to numerous details which a high-level language would handle automatically, but it also requires memorizing or looking up numerical codes for every instruction that is used. For this reason, second generation programming languages abstract the machine code one level. Example: A function in 32-bit x86 machine code to calculate the nth Fibonacci number: 8B542408 83FA0077 06B80000 0000C383 FA027706 B8010000 00C353BB 01000000 B9010000 008D0419 83FA0376 078BD98B C84AEBF1 5BC3 Second generation The second-generation programming language, or 2GL, is assembly language. It is considered a second-generation language because while it is not a microprocessors native language, an assembly language programmer must still understand the microprocessors unique architecture (such as its registers and instructions). These simple instructions are then assembled directly into machine code. The assembly code can also be abstracted to another layer in a similar manner as machine code is abstracted into assembly code. Example: The same Fibonacci number calculator as above, but in x86 assembly language using MASM syntax: fib: mov edx, [esp+8] cmp edx, 0 ja @f mov eax, 0 ret @@: cmp edx, 2 ja @f mov eax, 1 ret @@: push ebx mov ebx, 1 mov ecx, 1 @@: lea eax, [ebx+ecx] cmp edx, 3 jbe @f mov ebx, ecx mov ecx, eax dec edx jmp @b @@: pop ebx ret Assembly languages are close to a one to one correspondence between symbolic instructions and executable machine codes. Assembly languages also include directives to the assembler, directives to the linker, directives for organizing data space, and macros. Macros can be used to combine several assembly language instructions into a high level language-like construct (as well as other purposes). There are cases where a symbolic instruction is translated into more than one machine instruction. But in general, symbolic assembly language instructions correspond to individual executable machine instructions. High level languages are abstract. Typically a single high level instruction is translated into several (sometimes dozens or in rare cases even hundreds) executable machine language instructions. Some early high level languages had a close correspondence between high level instructions and machine language instructions. For example, most of the early COBOL instructions translated into a very obvious and small set of machine instructions. The trend over time has been for high level languages to increease in abstraction. Modern object oriented programming languages are highly abstract (although, interestingly, some key object oriented programming constructs do translate into a very compact set of machine instructions). Assembly language is much harder to program than high level languages. The programmer must pay attention to far more detail and must have an intimate knowledge of the processor in use. But high quality hand crafted assembly language programs can run much faster and use much less memory and other resources than a similar program written in a high level language. Speed increases of two to 20 times faster are fairly common, and increases of hundreds of times faster are occassionally possible. Assembly language programming also gives direct access to key machine features essential for implementing certain kinds of low level routines, such as an operating system kernel or microkernel, device drivers, and machine control. High level programming languages are much easier for less skilled programmers to work in and for semi-technical managers to supervise. And high level languages allow faster development times than work in assembly language, even with highly skilled programmers. Development time increases of 10 to 100 times faster are fairly common. Programs written in high level languages (especially object oriented programming languages) are much easier and less expensive to maintain than similar programs written in assembly language (and for a successful software project, the vast majority of the work and expense is in maintenance, not initial development). Q4. Assembler can perform operations of search and sort? Give your comments? Ans. Assemblers can perform operations of search and sort. Below are the examples: Sorting: Again: MOV FLAG, 0 ; FLAGà ¢Ã¢â‚¬  ? 0 Next: MOV AL, [BX] CMP AL, [BX+1] ; Compare current and next values JLE Skip ; Branch if current XCHG AL, [BX+1] ; If not, Swap the contents of the MOV [BX+1], AL ; current location with the next one MOV FLAG, 1 ; Indicate the swap Skip: INC BX ; BXà ¢Ã¢â‚¬  ? BX +1 LOOP Next ; Go to next value CMP FLAG, 1 ; Was there any swap JE Again ; If yes Repeat process RET Searching: MOV FLAG, 0 ; FLAGà ¢Ã¢â‚¬  ? 0 Next: CMP AX, [BX + SI] ; Compare current value to VAL JE Found ; Branch if equal ADD SI, 2 ; SIà ¢Ã¢â‚¬  ? SI + 2, next value LOOP Next ; Go to next value JMP Not_Found Found: MOV FLAG, 1 ; Indicate value found MOV POSITION, SI ; Return index of value in list Not_Found: RET Q5. Assemblers which can be developed? Ans. The following information describes some of the changes that are specific to assembler programs: In the TPF 4.1 system, assembler programs were limited to 4 KB in size; in the z/TPF system, assembler programs can be larger than 4 KB. To exploit this capability, you can change your assembler programs to use: o The CLINKC, RLINKC, and SLINKC assembler linkage macros o Multiple base registers o Baseless instructions. * You can use the CALLC general macro in assembler programs to call C language functions. * In the TPF 4.1 system, the TMSPC and TMSEC macros were provided to set up the interface between C language programs and macro service routines written in assembler language. In the z/TPF system, the PRLGC and EPLGC macros set up this interface by simulating the prolog and epilog code generated by the GCC. The PRLGC and EPLGC macros were provided on the TPF 4.1 system through APAR PJ29640 so that new C library functions written on the TPF 4.1 system can be migrated with little or no changes; and the TMSPC and TMSEC macros are still supported on the z/TPF system so that library functions that were already coded with those macros can be migrated with little or no code changes. New library functions that are developed for z/TPF system must be coded with the PRLGC and EPLGC macros. Q6. Problems which can be resolved using two pass assembler? Can we generate both the passes in a single pass or not? Give your comments with example? Ans. A computer language in which each statement corresponds to one of the binary instructions recognized by the CPU. Assembly-language programs are translated into machine code by an assembler. Assembly languages are more cumbersome to use than regular (or high-level) programming languages, but they are much easier to use than pure machine languages, which require that all instructions be written in binary code. Complete computer programs are seldom written in assembly language. Instead, assembly language is used for short procedures that must run as fast as possible or must do special things to the computer hardware. For example, Figure 17 shows a short routine that takes a number, checks whether it is in the range 97 to 122 inclusive, and subtracts 32 if so, otherwise leaving the number unchanged. (That particular subtraction happens to convert all lowercase ASCII codes to their uppercase equivalents.) This particular assembly language is for the Intel 8086 family of processors (which includes all PC-compatible computers); assembly languages for other processors are different. Everything after the semicolon in each line is a comment, ignored by the computer. Two lines (PROC and ENDP) are pseudo instructions; they tell the assembler how the program is organized. All the other lines translate directly into binary codes for the CPU. Many of the most common operations in computer programming are hard to implement in assembly language. For example, there are no assembly language statements to open a file, print a number, or compute a square root. For these functions the programmer must write complicated routines from scratch, use services provided by the operating system, or call routines in a previously written library. There are two types of assemblers based on how many passes through the source are needed to produce the executable program. One-pass assemblers go through the source code once and assumes that all symbols will be defined before any instruction that references them. Two-pass assemblers (and multi-pass assemblers) create a table with all unresolved symbols in the first pass, then use the 2nd pass to resolve these addresses. The advantage in one-pass assemblers is speed which is not as important as it once was with advances in computer speed and capabilities. The advantage of the two-pass assembler is that symbols can be defined anywhere in the program source. As a result, the program can be defined in a more logical and meaningful way. This makes two-pass assembler programs easier to read and maintain. More sophisticated high-level assemblers provide language abstractions such as: Advanced control structures High-level procedure/function declarations and invocations High-level abstract data types, including structures/records, unions, classes, and sets Sophisticated macro processing Object-Oriented features such as encapsulation, polymorphism, inheritance, interfaces The translation performed by an assembler is essentially a collection of substitutions: machine operation code for mnemonic machine address for symbolic machine encoding of a number for its character representation, etc. Except for one factor these substitutions could all be performed in one sequential pass over source text.The factor is the forward reference(reference to an instruction which has not yet been scanned by assembler). Now its that the separate passes of two pass assemblers are required to handle forward references without restriction. Now if we impose certain restriction that means handling forward references without making two passes. These different sets of restrictions lead to one pass assembler. And these one-pass assembler are particularly attractive when secondary storage is either slow or missing entirely, as on many small machines.

Illusions in J.D. Salinger´s Catcher in the Rye Essays

Do not be mislead by what you see around you, or be influenced by what you see. You live a world which is a playground of illusion, full of false paths, false values and false ideals. But you are not part of that world (Sai Baba). A world of illusion is an alluring, yet perilous place to enter. It can deceive the mind only to cause damage and distress. Holden Caulfields life has led to. an atrophy through his struggle of conceiving illusions as reality. In J.D. Salingers novel, The Catcher in the Rye, Holden Caulfield battles the constant reminder of his brother, Allies, death while he roams the streets of New York. Preceding his futile adventures, he is expelled from his fourth school, Pencey Prep. During his extent at†¦show more content†¦By hiding from this adolescent problem, Holden only reprieves the situation. As Holden aspires to be the catcher in the rye, he includes his red hunting hat. This is a people shooting hat...I shoot people in this hat (Salinger 22). Holden becoming the catcher is arguably the biggest illusion in this novel. This quote is taken in a metaphorical sense as to his armor or protection when he saves people in the rye from any maturation. When he puts on this hunting hat, he instantly feels the prerogative to become the catcher. He continues to reach for this duty as the catcher in the rye, but this prevails over his intuition and common sense on indispensable issues. In the climax when Holden watches Pheobe on the carrousel, he puts on his hat as a protection from the non-precedent rain. My hunting hat gave my quite a lot of protection, in a way, but i got soaked anyway. I didnt care though. I felt so damn happy all of a sudden (Salinger 212-213). Throughout this novel, Holden had perceived this hunting hat as a full protection and a barrier in between him and the rest of the world. In this scene, Holden finally understands that this hat cannot protect him forever. 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Phil 235 Paternalism Essay Free Essays

string(120) " neglect the fact that there is an obvious difference in the degree of knowledge between the patient and the physician\." Paternalism in the Medical Profession Philosophy 235 EC: Biomedical Ethics â€Å"The only appropriate and realistic model of the Dr.? patient relationship is paternalism. Doctors are the medical experts; most patients have little, if any, reliable medical knowledge; implicit trust in one’s physician is essential to the healing process; and doctors have the responsibility for our health and therefore have the duty to make all the important medical decisions. We will write a custom essay sample on Phil 235 Paternalism Essay or any similar topic only for you Order Now † Critically assess that claim. The issue of doctor patient relationships has become more and more prevalent in our world today. It is hard to draw a clear line in deciding what the appropriate roles are of both the patient and the medical professional. The claim that the paternalistic model is the appropriate and most realistic model will be argued in this paper. This model states that the doctor is the one in complete control, making all decisions on behalf of the patient, and the patient grants the doctor this responsibility, obeying any orders. In this model, patients act as children, who are ignorant and unknowledgeable, and doctors act as parents, not only guiding the child in the right direction, but also, actually telling them what to do. Should doctors really hold complete responsibility for our health? Should they be the ones to make all the important medical decisions without patients having any say? This model will be argued in this paper in order to critically assess whether it should be dominant in our present society. â€Å"The traditional view held by physicians themselves was that the physician is the captain of the ship, and that the patient has to follow orders. † This view has only been strongly believed since the 19th and 20th century, when medical professionals were granted almost complete control over all decision making by their patients. Before that time, going to see a doctor was perceived as a last resort, and many would ignore their doctor’s advice altogether. Over time, this view has shifted and society began to believe that physicians â€Å"knew best, and therefore had not only the right but also the duty to make the decision. † Today, less and less citizens are continuing to agree with this point of view, and instead other doctor patient relationship models have emerged and been identified by Robert Veatch: the engineering model, the priestly model, the collegial, and the contractual model. The three alternative models to the priestly (paternalistic) model have emerged from a more contemporary perspective. The engineering model states that the relationship between the two parties would be nothing more than the doctor simply presenting the patient with the diagnosis, prognosis, and treatment options. Any decision as to which route to take is left entirely up to the patient. As the textbook explains, the doctor is nothing more than an â€Å"applied scientist†, or a â€Å"plumber without any moral integrity†, since ethics and values do not come into play in this relationship. Although I do not entirely agree with this model, the responsibility is lifted off of the physician, and the patient is given freedom to decide. This would follow the argument of self-determination, as said by Dr. Ornstein. This is the belief that all people who are competent should be the ones in control of determining their own fate. Society has not always believed or relied on medical professionals. In fact â€Å"until well into the nineteenth century, the physician was seen as a figure of last resort. † They were deemed useless and even harmful. With this in mind, I wonder why in our day and age, we would rely even more on physicians than we did in the past? Today, we have the privilege of finding out almost anything we need to know within minutes via the Internet, and that is why sometimes, it is the patient that knows more than his own doctor. It is important that patients assume some level of responsibility for their own health, instead of relying on doctors, and the engineering model would display that type of behavior. That is another reason why I oppose the claim that paternalism is the ideal relationship between doctor and patient. Another alternative model identified by Robert Veatch, is the collegial model. This theory emphasizes that both parties are connected through common goals and interests, and that each acts as an independent equal. This model would suggest that the parties work together, and therefore the responsibility is divided equally amongst the patient and physician. There is collaboration here, engaging in activities, which are satisfying to both, and demonstrating an adult-adult relationship, because no one party has greater control over the other. This model goes hand in hand with the partnership model, which expresses that health care professionals and their patients act as partners or colleagues in the pursuit of the shared value of health. There is mutual participation in this model, which demonstrates that, unlike the paternalistic model, the patient can help come to a medical decision. This model stresses, â€Å"the patient uses expert help to realize his ends. † This expert help can come in many forms, and as I have previously mentioned, today society is exposed to numerous modes of gathering any type of information that is of interest. It is of course obvious that the physician has a stronger medical background and is more competent in that field, but that does not diminish the participation or contribution of the patient. With that being said, it is my opinion that the paternalistic model has clearly outgrown our culture, when there are models such as the partnership or collegial model, which are more in sync with our world today. Finally, the third alternative to the paternalistic model is the contractual model. This model is similar to paternalism, in that it questions the assumptions of equality, however it differs in that there is a â€Å"contract† between both parties, leaving each with their own dignity and moral authority. What is crucial about this model is that it does not neglect the fact that there is an obvious difference in the degree of knowledge between the patient and the physician. You read "Phil 235 Paternalism Essay" in category "Essay examples" Instead of focusing on that discrepancy, the model concentrates on the agreement between the two parties to exchange goods and services and the enforcement of that by government sanctions. In other words, this model compromises between partnership and the reality of medical care, and according to Veatch, is the only realistic way to share all responsibility, while protecting various parties in health care. For example, both parties are freely entering this contract, and therefore are both given the right to leave it, given proper notice. However, while partaking in the contract, there are duties and obligations of each, which may neglect virtues of benevolence, care and compassion, which we do see stressed in other models. Leaving aside the three alternatives to the paternalistic model, there are several other arguments, which come to surface, when critically assessing the above-mentioned claim. The first is that doctors must act like parents because patients know much less than doctors do. This emphasizes the idea that the doctor patient relationship should be one of paternalism. This argument takes into account two different prototypes. The first is the parent-infant relationship, where the parent is the doctor, taking on an active role and the infant is the patient, taking on a passive role. In this case the patient is extremely dependent on the medical professional. The second is the parent-adolescent child relationship, where the physician guides the patient in the right direction, and the patient co-operates to the degree of obeying. Both suggest that the patient has no responsibility, and that the duty and obligation of all decisions rest on the shoulders of the physician. This proposes that patients are ignorant and unknowledgeable and given the opportunity to make their own decision, they would not be able to. It is likely that doctors know more than the average member of society, however, this is not to say that they are infallible, mistakes can happen. As Professor Ornstein has stated, we cannot choose our fathers, but we can choose our doctors, and in my opinion there is no connection where the two should be related. If a patient feels they should seek out a second, third or fourth opinion, that is their own right. Unlike the ability to seek out a second, third or fourth father. We do not have this option. It is possible and even probable that doctors will differ in their views, and each may guide their patient down a different path. Although a relationship between a physician and a patient should be based on a degree of trust and loyalty, if there is any sort of uncertainty, patients should not feel the pressure of following a path they do not believe in. Getting another opinion is not disloyal or disrespectful; it is a patient’s right. Additionally, today more patients recognize that it is unfair for doctors to take complete responsibility for our welfare, as we are exposed to so much free medical information. It is my opinion that it is the patient’s duty to also act responsible for his or her own welfare. Another argument that I have come across to oppose this claim is that doctors may be experts in medical matters but there may be other factors to take into account, such as ethical issues, when making a decision. Each doctor has taken an oath, to save lives. This is their main concern, and their main goal for each patient. One must wonder, whether or not this is always ethical. As Professor Ornstein has suggested, do we save someone who as a result must live the rest of his or her life in agonizing pain? Or do we relieve them of that pain, and simply allow them to pass away? This is an ethical issue where many doctors may have opposing points of view, and may decide that their job would be to save the patient. That would be a paternalistic instinct however; medical decisions should not be purely medical all the time. There are always other factors to consider such as the medical conditions of the patient, their preferences, the quality of life and the socio economic conditions. Each, of course, is given a weight dependent on the specifics and circumstances of the case. In the case of a patient who is experiencing excruciating pain, the doctor may come to the conclusion that the best option would be to remedy that pain with medication. It is important to note, that this paternalistic act is ignoring all ethical issues and only taking medicine into account. Opposing this notion would be to consider how this medication might cloud the patient’s judgment, or recognizing the patient’s preferences prior to formulating a medical decision. Doctors might be experts in medical matters, but the other factors, which are necessary to take into consideration, deem the paternalistic view inadequate. A final argument against the paternalistic view is that physician-patient interactions are negotiations. Viewing the interactions as negotiations, is in itself opposing paternalism because the patient is given some level of autonomy to take part in the decision making process. The goal is to reach a mutual agreement. In order to do so, there are certain steps that must be followed. Firstly, the negotiation should involve adequate disclosures by both parties. This is necessary, so that values and objectives are clear, and a fair negotiation can take place. Secondly, the negotiation should be voluntary, meaning uncoerced. Neither party should feel threatened while entering into the negotiation process. And finally, the solution should be one of mutual acceptance. Of course there are occasions where negotiation is not possible, and that would be for example in the case of an emergency, when the physician needs to save the patient without negotiating beforehand. In that case, the medical professional may act in a paternalistic way, however if there is a competent patient, negotiation is possible and can often be characterized in terms of any of the above-mentioned models (parent-child, friends, partners, etc. ). The aspect that the relationship is seen as a negotiation counters the paternalistic view, in that the patient is given choice. If the patient chooses to give up his autonomy, and lay his destiny in the hands of his physician, that is his preference, unlike the paternalistic model, where that is not a choice, but the only way. The paternalistic model is not the only realistic relationship between doctor and patient. â€Å"As a normative model, paternalism tends to concentrate on care rather than respect, patients’ needs rather than their rights, and physicians’ discretion rather than patients’ autonomy or self determination. As I have mentioned previously, there are many other factors that must always be taken into consideration when dealing with a patient. Autonomy, self-determination, and respect, are surely incredibly important when dealing with a patient, and paternalism ignores those factors. The above-mentioned arguments, and alternative relationship model s, clearly oppose the claim that paternalism is the only appropriate relationship. As I had asked the questions: Should doctors really hold complete responsibility for our health? Should they be the ones to make all the important medical decisions without patients having any say? I believe the answer to both questions is quite clear, that the responsibility should be shared, and the patient, if capable, should take part in the decision making process. That being said, paternalism is not the most appropriate model and no one relationship trumps another. Instead, all must be taken into account depending on circumstance. 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Diversity Affects Communication free essay sample

Diversity Affects Communication Victoria Moore University of Phoenix Introduction to Communication COM/100 Bruce Turner January 03, 2010 Diversity Affects Communication 1. What is cultural diversity? Why is an appreciation of diversity important in communication? Cultural diversity is having a group made up of people from various ethnicities, backgrounds, religions, etc. Having an appreciation of diversity is extremely important and essential for effective communication. For example, if you are a person that makes a lot of gestures to express yourself but you are attempting to communicate with someone who comes from a culture that does not utilize gestures; you would want to take this into consideration so that you do not come across as rude or offensive to the person that you are communicating with. 2. How would you describe your cultural background? How do your values affect the way you communicate with others and the way they communicate with you? Culture can be defined as â€Å"system of shared ideas and meanings, explicit and implicit, which a people use to interpret the world and which serve to pattern their behavior’. We will write a custom essay sample on Diversity Affects Communication or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page That being said my cultural background is very diverse. I am a young, African-American woman. An immediate assumption would be that I am liberal in both actions and ideas; however, that is false. I actually tend to have very conservative view points since I am also moderately religious. My values and my upbringing affect almost every aspect of my everyday life including the way that I communicate with other. The values that have been instilled in me is what tells me to be respectful to others and in return demand respect for myself. For example, I was in my very early twenties when I was a manager at the hotel that I work at. Most of the people that I managed were older than I was; however, they understood that I could be very personable and relate to them on a social level but I also could handle business. 3. How do gender differences affect communication? As I get older, and hopefully wiser, I learn more about how gender affects communication. I have learned how to communicate with the opposite sex by learning what they are influenced/hindered by. For example, I know that the worst time to communicate with my boyfriend is when he is watching any type of sporting event. I have learned that during this time anything I say goes in one ear and out the other. I have also learned that like the saying goes â€Å"You attract more flies with honey than with sugar. What this means in terms of communication with the opposite sex is that sometimes you can flash a nice smile to get something you want. Also, the ways that men and women communicate are very different. Usually men are more straightforward and to the point whereas women tend to elaborate more and tend to also be more emotional when communicating. 4. Describe three barriers to bridging differences. What strategies may you use to overcome them? Three barriers that were mentioned in the reading are: 1) Stereotyping and prejudice: These are opinions that are formed and are most likely wrong about a group of people. This can be overcome by simply not judging a book by its cover. We should not rush to form opinions or imply certain things about people based on their ethnicity, religion, sexual orientation, etc. 2) Assuming superiority: As the text mentioned, this is one of reasons that our country has terrorists attacks aimed at us. Our country is hated by numerous others because we infer that we are the best, the richest, the most powerful. This can be overcome by communicating more with other countries and not just imposing our will on them. 3) Assuming similarity: This is an assumption that other people think and act the way that you do. This can be overcome by taking other peoples thoughts and ideas into consideration. 5. Identify three advantages and three challenges of working in a multicultural team. Three advantages of working in a multicultural team could be: 1) Unique viewpoints: Someone may have a new and unique way of looking at something or resolving an issue. 2) Opportunity to learn: Sometimes we get so stuck in our own box that we forget that there are other rich cultures out there that we could learn about. ) Opportunity for understanding: We may be able to understand more about a person or culture by understanding what they have gone through. Three challenges of working in a multicultural team could be: 1) Communication barriers: There may be a language or some other type of communication barrier that could be a hindrance to a team. 2) Inability to see past differences: Sometimes there may be so much cultural tension that you may not be willing to work through them. ) Different ways of working: Some cul tures may have a mentality of getting things done as soon as possible while others may believe in taking their time. 6. Does diversity affect ethical decisions? Explain your answer. I think that diversity does affect ethical decisions because different cultures are going to have different ways of looking at ethical issues. For example, the issue of abortion may be more accepted in culture as opposed to another, therefore people from those cultures are going to have two very different opinions about it.

Othello uses many different rhetorical devices to Essays

Othello uses many different rhetorical devices to persuade and show the Venetians that he is not a threat. Othello uses his skills in rhetorical devices to show the Venetians that he isn't a treat to them. Othello starts out using an appeal to emotion or ethos by saying "Her father loved me" to help him in his persuasion by showing an emotional side. He uses an appeal to emotion to try and bring out the emotion in the Venetians, so they will side with him. Othello then uses anaphora many times by saying "Of moving accidents by flood and field, Of hairbreadth 'scrapes i' th' imminent deadly breach, Of being taken by the insolent foe" and then in the next few lines saying "And sold to slavery, of my redemption thence, And portance in my traveler's history," in order to prove his point more and draw more of their attention. Othello is using anaphora to show the Venetians what he was talking about. He then in the very next line uses imagery to talk about his travels and give the Venetians an image of where he went, to help guide them in his defense, by saying "And portance in my traveler's history, Wherein of oceans vast and deserts idle,". Othello then goes on to using personification when he says, "Rough quarries, rocks, and hills whose heads touch heaven" because quarries rocks, and hills can't really touch heaven. HE says this to exaggerate and explain the scenery he saw on his travels to help prove that he isn't a threat. When Othello says "And of the cannibals that each other eat," he is using an appeal to logic or logos because it is a fact that cannibals eat each other. He uses an appeal to logic to show the Venetians that he knows they are smart and is just stating common knowledge. Othello then uses personification again by saying "She'd come again, and with a greedy ear" because ears can't really be greedy. Again Othello is just exaggerating what he knows, that when she were to come she would come with greed. He uses an appeal to emotion again by saying "And often did beguile her of her tears, When I did speak of some distressful stroke, That my youth suffered. My story being done, She gave me for my pains a world of sighs." Othello says this to try and get the Venetians to feel sympathy for him to try and sway their position on whether he is a threat or not. Othello then again uses anaphora to help his case in trying to prove that he isn't a threat by saying "She swore, in faith, 'twas strange.'twas passing strange, 'Twas pitiful, 'twas wonderous pitiful." When Othello says this he is trying to emphasize how weird and pitiful her swearing was. In this passage Othello uses many different kinds of rhetorical devices to help him prove that he isn't a threat to the Venetians.

How to Style Compounds After the Noun

How to Style Compounds After the Noun How to Style Compounds After the Noun How to Style Compounds After the Noun By Mark Nichol Most but not all phrasal adjectives (two words that combine to modify a noun hence the alternate name, compound modifiers) are hyphenated, which is confusing enough though easily resolved: If a permanent compound is listed in the dictionary as open, no hyphen is necessary; otherwise, hyphenate. But that applies only before the noun. What happens after the noun is a whole other matter: Usually, phrasal adjectives and similar (or similar-looking) constructions are left open in that position. Here’s a rundown on hyphenation rules for various types of compounds: Categories Age compound: â€Å"The eighteen-year-old (boy),† but â€Å"He is eighteen years old.† Color compound: â€Å"The sky-blue paint,† but â€Å"The paint is sky blue.† Fraction compound: â€Å"A half-mile walk,† but â€Å"a walk of a half mile.† Number, spelled out: â€Å"Fifty-one,† â€Å"five hundred,† five hundred one,† â€Å"two thousand twenty-two.† (Hyphenate tens-ones figures in isolation and in larger figures, but leave open all other combinations of places.) Number plus noun: â€Å"A five-year plan,† but a plan that will take five years†; â€Å"a four-and-a-half-inch gap,† but â€Å"a gap of four and a half inches†; â€Å"the fourth-floor office,† but â€Å"an office on the fourth floor.† Number plus superlative: â€Å"The third-tallest player,† but â€Å"a player who is third tallest.† Time: â€Å"They’re going to the eight o’clock screening† and â€Å"The meeting starts at six (o’clock)†; â€Å"I have a five-thirty plane to catch,† but â€Å"I’ll meet you at five thirty† (always open when time is on the hour, and hyphenated before the noun but open after when time is between hours). Parts of Speech Adjectival phrase: â€Å"His matter-of-fact manner,† but â€Å"His manner was matter of fact.† Adjective plus noun: â€Å"A low-class joint,† but â€Å"The joint is low class.† Adjective identifying origin or location plus noun: â€Å"An Indo-European language† and â€Å"the French-Spanish border,† but â€Å"She is a Japanese American† and â€Å"the latest Middle East crisis† (open unless the first term is a prefix or there is a sense of a distinction between the elements). Adjective plus participle or adjective: â€Å"His long-suffering wife,† but â€Å"his wife is long suffering.† Adverb ending in -ly plus participle or adjective: â€Å"Her rapidly beating heart† (always open). Adverb not ending in -ly plus participle: â€Å"The little-read novel,† but â€Å"The novel is little read.† (See â€Å"More About Adverbs,† below.) Noun phrase: â€Å"A feather in your cap,† but â€Å"He’s a jack-of-all-trades† (open unless hyphenated in the dictionary). Noun plus adjective: â€Å"The family-friendly restaurant,† but â€Å"The restaurant is family friendly.† Noun plus gerund: â€Å"A note-taking lesson,† but â€Å"a lesson in note taking.† (But beware of closed noun-plus-gerund compounds like matchmaking.) Noun plus noun, the first one modifying the second: â€Å"A tenure-track position,† but â€Å"She’s on the tenure track.† (But leave permanent compounds like â€Å"income tax† open even before a noun, and check for closed noun-plus-noun compounds like bartender.) Noun plus noun, equivalent: City-state, nurse-practitioner (always hyphenated). Noun plus letter or number: â€Å"A size 34 waist,† â€Å"the type A personality† (never hyphenated). Noun plus participle: â€Å"A problem-solving exercise,† but â€Å"time for some problem solving.† Participle plus noun: â€Å"Working-class families,† but â€Å"members of the working class.† Participle plus prepositional adverb plus noun: â€Å"Turned-up nose,† but â€Å"Her nose was turned up.† More About Adverbs When less or more modifies an adjective, such as in â€Å"a less frequent occurrence†/â€Å"an occurrence that is less frequent† or â€Å"a more qualified candidate†/â€Å"a candidate who is more qualified,† the phrase is not hyphenated either before or after a noun. The same is true of least and most unless ambiguity is possible. For example, â€Å"a lesser-known rival† is a rival who is not as well known, but â€Å"a lesser known rival,† by contrast, might be a known rival of lesser consequence. Likewise, â€Å"the most-quoted orators† and â€Å"the most quoted orators† refer, respectively, to orators most frequently quoted and a majority of quoted orators. Again, however, the hyphenated version would be left open when it follows a noun, and would likely be worded differently than its counterpart that is not hyphenated before the noun, either. Also, when an adverb that is part of a modifying phrase is modified by another adverb, as in â€Å"a very much praised debut,† the phrase is not hyphenated at all, even though a hyphen would appear in â€Å"a much-praised debut.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Style category, check our popular posts, or choose a related post below:Useful Stock Phrases for Your Business EmailsAwoken or Awakened?Particular vs. Specific

Elements in the Human Body and What They Do

Elements in the Human Body and What They Do There are several ways to consider the composition of the human body, including the elements, type of molecule, or type of cells.  Most of the human body is made up of water, H2O, with cells consisting of 65-90% water by weight. Therefore, it isnt surprising that most of a human bodys mass is oxygen. Carbon, the basic unit for organic molecules, comes in second. 99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Oxygen (O) - 65% - Oxygen together with hydrogen form water, which is the primary solvent found in the body and is used to regulate temperature and osmotic pressure. Oxygen is found in many key organic compounds.Carbon (C) - 18% - Carbon has four bonding sites for other atoms, which makes it the key atom for organic chemistry. Carbon chains are used to build carbohydrates, fats, nucleic acids, and proteins. Breaking bonds with carbon is an energy source.Hydrogen (H) - 10% - Hydrogen is found in water and in all organic molecules.Nitrogen (N) - 3% - Nitrogen is found in proteins and in the nucleic acids that make up the genetic code.Calcium (Ca) - 1.5% - Calcium is the most abundant mineral in the body. Its used as a structural material in bones, but it is essential for protein regulation and muscle contraction.Phosphorus (P) - 1.0% - Phosphorus is found in the molecule ATP, which is the primary energy carrier in cells. Its also found in bone.Potassium (K) - 0.35% - Potassium is an im portant electrolyte. Its used to transmit nerve impulses and heartbeat regulation. Sulfur (S) - 0.25% - Two amino acids include sulfur. The bonds sulfur forms help give proteins the shape they need to perform their functions.Sodium (Na) - 0.15% - Sodium is an important electrolyte. Like potassium, it is used for nerve signaling. Sodium is one of the electrolytes that helps regulate the amount of water in the body.Chlorine (Cl) - 0.15% -  Chlorine is an important negatively-charged ion (anion) used to maintain fluid balance.Magnesium (Mg) - 0.05% - Magnesium is involved in over 300 metabolic reactions. Its used to build the structure of muscles and bones and is an important cofactor in enzymatic reactions.Iron (Fe) - 0.006% - Iron is found in hemoglobin, the molecule responsible for oxygen transport in red blood cells.Copper (Cu), Zinc (Zn), Selenium (Se), Molybdenum (Mo), Fluorine (F), Iodine (I), Manganese (Mn), Cobalt (Co) - total less than 0.70%Lithium (Li), Strontium (Sr), Aluminum (Al), Silicon (Si), Lead (Pb), Vanadium (V), Arsenic (As), Bromine (Br) - pres ent in trace amounts Many other elements may be found in extremely small quantities. For example, the human body often contains trace amounts of thorium, uranium, samarium, tungsten, beryllium, and radium. Trace elements considered essential in humans include zinc, iodine, possibly silicon, probably boron, selenium, probably nickel, chromium, manganese, lithium, possibly arsenic, molybdenum, cobalt, and possibly vanadium. Not all of the elements found within the body are essential for life. Some are considered contaminants that appear to do no harm, but serve no known function. Examples include cesium and titanium. Others are actively toxic, including mercury, cadmium, and the radioactive elements. Arsenic is considered to be toxic to humans, but serves a function in other mammals (goats, rats, hamsters) in trace amounts. Aluminum is interesting because it is the third most common element in the Earths crust, yet serves no known function in living cells. While fluorine is used by plants to produce protective toxins, it serves no essential biological role in human beings. You may also wish to view the  elemental composition of an average human body  by mass. Sources Chang, Raymond (2007). Chemistry, 9th Edition. McGraw-Hill. ISBN 0-07-110595-6.Emsley, John (2011). Natures Building Blocks: An A-Z Guide to the Elements. OUP Oxford. p. 83. ISBN 978-0-19-960563-7.Frausto Da Silva, J. J. R; Williams, R. J. P (2001-08-16). The Biological Chemistry of the Elements: The Inorganic Chemistry of Life. ISBN 9780198508489.H. A., V. W. Rodwell; P. A. Mayes, Review of Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos, California 1977.Zumdahl, Steven S. and Susan A. (2000). Chemistry, 5th Edition. Houghton Mifflin Company. p. 894. ISBN 0-395-98581-1. Elements in the Human Body and What They Do