# What is the neurilemma and what is it function?

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# What is it about Middle of Nowhere that makes it such a great film?

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In Health

# How do schwann cells form the myelin sheath and the neurilemma encasing the nerve processes?

Schwann's cells become apposed to an axon and envelops it in a trough. It then begins to rotate around the axon, wrapping it loosely in successive layers of its plasma membran…e. Eventually the Schwann's cell cytoplasm is forced from between the membranes and comes to lie peripherally just beneath the exposed portion of the Schwann's cell membrane. (MORE)

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In Health

# What is Neurilemma sheath or sheath of schwann?

Surrounding the myelin sheath, there is a thin membrane called neurilemmal sheath. This is also called neurilemma or sheath of Schwann. This contains Schwann cells, whic…h have flattened and elongated nuclei. The cytoplasm is thin and modified to form the thin sheath of neurilemma enclosing the myelin sheath. One nucleus is present in each internode of the axon. The nucleus is situated between myelin sheath adn neurilemma. At the node of Ranvier (where myelin sheath is absent), the neurilemma invaginates and runs up to axolemma in the form of a finger like process. In nonmyelinated nerve fiber, the neurilemma continuously surrounds axolemma. Neurilemma is absent in central nervous system. Neurilemma is necessary for the formation of myelin sheath (myelinogeneis). (MORE)

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In Technology

# What is function overloading or function polymorphism?

Actually, overloading and polymorphism are two different things. Overloading is when two different functions of the same name but of different parameter types co-exist. The …compiler determines which to call by looking at the match between parameter types. An example might be a sin function taking a parameter of type float versus an overloaded version taking a parameter of type long double. In the first case, only a few terms of the taylor's series is needed for reasonable precision; in the second case, you need more than that. Polymorphism, on the other hand, is when the class type of the function is known only by virtue of a pointer to a class of that class, typically a pointer that is declared to hold a pointer to the base class but, at run-time, assigned to hold a pointer to one or the other of two derived child classes. An example might be an area function that computes the area of a shape, that might be derived to be a circle, a square, an ellipse, etc. (MORE)

In File Types

# The SIGN Function in Excel

Excel is an incredibly versatile program. It can be used to achieve very simple ends, such as recording your income each month; or it can be used for complex databases and dat…a analysis. Data that is entered into a spreadsheet can be processed and manipulated in many types of ways, thanks to Excel's extensive selection of functions. SIGN is one of Excel's simpler functions. It returns the sign of any whole number provided as an argument.Excel allows data to be processed in many ways thanks to a large selection of function types. Some functions are used regularly, such as SUM, which simply sums all the values in an array. Other functions have very specific applications, and are more likely to be used by developers. SIGN, despite being a very simple function to use, falls into the latter category. Returning the sign of a number will mainly be of use in complex mathematical processes."Sign" is a mathematical concept. All non-zero numbers have a sign. A number greater than zero is positive. A number less than zero is negative. Zero is signless. A number's sign is often denoted through the use of the plus symbol for positive numbers (+) and the minus symbol for negative numbers (-).SIGN is one of Excel's most basic functions. It is used to return the sign of a number. It accepts a single whole number as an argument. It will output one of three responses, based on the argument provided. If the argument evaluates to zero, then the function returns "0." If the argument evaluates to a negative value, the function returns "-1." If the argument evaluates to a positive value, the function returns "1." To insert the SIGN function into an open workbook file (spreadsheet), click on any cell to make it active. Type the function as: =SIGN([number]). The equals sign at the start of the function is important, as it lets Excel know that you have entered a function rather than a text string. The value of "number" is the argument you are evaluating. This could be a hard-coded number, or it could be a cell reference. It is also possible to use the SIGN function as an argument for other functions.As a simple example, imagine you have the value 50 in cell A1. To evaluate the sign of that value, you would use the formula: =SIGN(A1). The result would be "1," as the value is positive. If you want to, you can also use SIGN as part of more complex formulas. For example, if you want to convert the numerical output of SIGN into words, you could use a formula such as: =IF(SIGN(A1)=1,"positive","zero or less"). In this example, if the value of A1 is positive, the function will display the word "positive," otherwise it will display "zero or less."Excel has an incredibly diverse range of functions. Some of them are very useful in many situations, and you will find yourself using them often. Other functions have much narrower applications, and you may never need them at all. The SIGN function is very simple to use, as it accepts a single whole number as an argument, and then returns the sign of that number."Sign" is a mathematical concept. All non-zero numbers have a sign. A number greater than zero is positive. A number less than zero is negative. (MORE)

In Functions

# Master the Ceiling Function in MS Excel

Microsoft Excel spreadsheets are easy to use because of the many built-in functions. One such useful feature is the ceiling function. You can use it to round up numerical valu…es as desired. Its most common application is in dealing with prices, where nickels and pennies are rounded off to dimes.The ceiling function is used to round off a numerical value with or without a decimal part. You can specify the closest multiple to which the rounding off must be done. This is always done on the higher side by default. There are a maximum of three variables within this Excel function. Of these, only the first variable is mandatory.To apply the ceiling function to a particular cell in an Excel spreadsheet, type "= CEILING (number, significance)." The first variable inside the brackets is the numerical value that needs rounding off. The function's second variable is its significance; the number will be rounded off to the nearest multiple of this value. You can assign integer or decimal values to the significance variable. If no value is specified, a default value of 1 is used to round up the number to the nearest integer. Just like positive numbers, negative numbers are generally rounded off on the upper side, which is closer to zero. For example, -3.4 would be rounded off as -3. You can change this by assigning a value of 1 to a third variable, called mode. With this, the resultant value after rounding off will be -4. Note that the mode does not apply to positive numbers.You may not always remember the syntax of the ceiling function. The easier option is to choose it from the drop down menus provided in Excel. You need to choose "Math & Trig" from the menu, and then select "ceiling" from the list. The required function will open up in a dialog box. Here, you can replace its variables with the appropriate values. Once you have applied this function to a particular cell, it can be extended across that row or column by dragging the cell from its bottom-right corner.CEILING (43.63, 0.10) is an example showing how this function works. Its result will be 43.7 even though 43.63 is numerically closer to 43.6. Adding the mode variable as 1 to this function will not change its result. In the case of negative numbers, CEILING (-43.63, 0.10) will give you -43.6. Here, you can change the direction of rounding off by adding the mode. So, CEILING (-43.63, 0.10, 1) gives -43.7. Microsoft Excel's functions help you to work with numerical values in many ways. Trailing decimal places can get tedious, especially when their length varies between numbers. The ceiling function is very useful in rounding off these values to a fixed number of decimal places or to the nearest integer. You can then sum up the rounded numbers or use them in other formulae.Microsoft Excel's functions help you to work with numerical values in many ways. Trailing decimal places can get tedious, especially when their length varies between numbers. The ceiling function is very useful in rounding off these values to a fixed number of decimal places or to the nearest integer. (MORE)

In Functions

# How to Use the Excel WORKDAY Function

In Excel there are various functions. They perform analytical and mathematical calculations in a variety of categories. One such category is "Date & Time". All functions here …relate to determining or assessing date or time in some capacity. One under this category is the WORKDAY function. It returns the serial date when a start date and a number of days are entered as criteria.Double-click the Excel desktop or taskbar icon. If you do not have one, access the program from the Windows Start Menu. Search for it if needed. Once the workbook opens select the new option.Technically you do not need to save unless you want this book for later. It is a good idea, however, to stay in the habit of saving your workbooks before you begin work. To do so click on the floppy disk icon in the upper left-hand corner of the screen, find your file location, enter your filename, and press enter.Select cell A1. Enter the text "11/12/2013". Select cell A2. Enter the number "130".Select cell A3. Scroll to the ribbon. Click on the "Formulas" tab. Under the tab select the "Function Library". Scroll to "Date & Time" and click on it to reveal a drop down menu. From this menu select the WORKDAY function.The first line in the function window is "Start_date". This will be the beginning point from which the day count will proceed. On this line type A1, which will select cell A1.The second line for the function argument is "Days". On this line type A1, which will select cell A2. This will select the number "130". Press enter.In cell A3 the result "41772" has been returned. This is the serial date for the day occurring 130 days after 11/12/2013. Click on the A3 cell to reveal the code inside. You could manually enter this function with the given formula layout visible in cell A3.There is an easy way to change the format of the serial date. Click on cell A3. Scroll to the ribbon and select the home tab. On the home scroll to the left and look under the "Number" category. In here is a small window with an arrow for a drop-down menu. By default this windows shows "General". Click on the arrow to reveal the drop-down menu. Scroll to "Short Date" and select it. The number in cell A3 changes from 41772 to 5/13/2014.You now know how to use the Excel WORKDAY function. However, you may still be confused by the result of 41772. This result is the serial number used by Excel. It represents that number of days that have passed to the date in questions since 1/1/1900, which is the first serial date in Excel for Windows. You should have also noticed the function window allows you to enter dates for holidays. This allows you to account into these holidays and plan around them. For example, you could have entered 12/25/2013 for Christmas, and the result would have been pushed out one more day, making the final result 41773. This function is ideal when you need to plan a specific number of workdays to a project and want a specific end date.There are functions that carry similar properties to WORKDAY or perform related functions. WEEKNUM returns the actual week number in the year from the Microsoft serial number. WEEKDAY is very similar to WEEKNUM and returns the number value of the day based on the date. Other related functions include YEAR, TODAY, and WORKDAY.INTL. (MORE)

In Symptoms

# Impairment of Executive Function in ADHD

Executive function plays a key role in Attention Deficit Hyperactivity Disorder (ADHD). It is the part of our brains that orchestrates our actions and what we do. People with …ADHD have trouble with executive function, which manifests into many common ADHD symptoms. (MORE)

# 6 Easy Tips on Improving Executive Functioning Skills

Executive functions refers to the cognitive processes that manage the following skills: planning, working memory, attention, problem solving, verbal reasoning and other functi…ons. Individuals who have a deficit in executive functioning skills have difficulties in the area of organizing, planning, remembering details, paying attention and strategizing. Does your child need ways to improve their executive functioning skills? Here are some simple ways to strengthen their executive functioning skills at school and at home. Provide students with a homework folder and a classwork folder. Having two separate folders keeps their work more organized. Students are clear in knowing what needs to go in each folder. Assigning color coded folders for each subject is also beneficial for them too. Post class schedules so students with deficits in executive functioning skills can see them. Teachers should also review the daily schedules with the student. At home, post the weekly homework schedule in an area that they can see on a daily basis. This is especially important for long term project due dates. In the classroom, the teacher should breakdown the directions for students. Short and simple instructions make it easier to remember details. At home, parents can help children by breaking down multi-step homework instructions. Create a checklist of your student's daily tasks. When a task is complete they can check it off the list. At home this could be helpful when doing homework or projects. Students should keep the check list in their homework area so they can refer to it while doing homework and projects. In the classroom, students should sit in an area that has minimal distractions. This can improve their focusing skills. At home, children should have an area that is organized and away from noise and other distractions. Help your child keep his backpack neat. On a daily basis have your child clean out his backpack and remove all unnecessary papers. Have them unpack their backpack in front of you so you can model the process. Eventually, they will be able to do this on their own. Executive functioning skills are crucial to learning. Individuals with deficits in executive functioning skills can also experience issues with self-esteem, anxiety and some times misbehavior. Students with deficits in executive functioning skills have difficulty with organization, paying attention, remembering details and planning. Give them the tools they need to improve their executive functioning skills by implementing these easy tips. Soon their forgetfulness, disorganization and inattentiveness will be a thing of the past! (MORE)

In Anatomy

# Introduction to the Hypothalamus

You would think that the brain would be the brains of all the operations concerning human anatomy. If you thought this, you would be thinking wrongly. There is a small pearl-s…ized part called the hypothalamus that is responsible for directing a multitude of bodily functions. It is the command center for our peripheral nervous system and many of our autonomic functions. As part of the limbic system, the hypothalamus is responsible for some of our emotional responses. Let's take a further look at what the hypothalamus does.There are several bodily functions that the hypothalamus regulates. The hypothalamus is a part of our autonomic and endocrine function control, blood pressure, temperature, homeostasis, food and water intake regulation, motor function control, and our sleep-wake cycle.The hypothalamus is in the lower region of the diencephalon. It is in the rear chasm of the optic region. The temporal lobes and optic tracts sit on either side of the hypothalamus and lies just above the brain stem.The hypothalamus is responsible for the control of hormones released from the pituitary gland. One of the most important hormones in this process is oxytocin. Oxytocin is very important to females during the birthing process. It also stimulates the flow of breast milk. The secretion of oxytocin can also be caused by hearing a baby cry; this insinuates a further connection of the hypothalamus to other bodily functions.Hypothalamic Amenorrhea is when menstruation stops due to a malfunction in the hypothalamus. The hypothalamus plays a critical role in the regulation of hormones. It produces a hormone called gonadotropin-releasing hormone (GnRH) which is responsible for releasing the egg during ovulation. Sometimes the hypothalamus will stop producing the GnRH and ovulation and menstruation will stop..The hypothalamus can be damaged due to injury, surgery, or degeneration due to disease or old age. The extent of the damage can vary vastly dependent on the area that is involved. Diabetes Insipidus reduces the production of vasopressin (a hormone from the pituitary), resulting a large amount of urine being made at all times. Other conditions attributed to a damaged hypothalamus are anorexia, obesity, sleep disorders, and psychiatric and sexual disturbances. Without a hypothalamus it would be impossible to live. The hypothalamus is responsible for many of the basic functions in a human life like heart rate, blood pressure, respiration, and digestion that you would not be able to survive without one.The hypothalamus is small in size, but gigantic in scope. It plays a role in some of the most basic functions required for sustaining human life. It is one of the most ancient parts of the human anatomy and has evolved over the centuries to a kind of control center for our peripheral nervous system and autonomic functions. Although it is a part and function, which mammals share with birds and reptiles alike, the mammalian hypothalamus is much more advanced.The hypothalamus is less than one percent of the total volume of the brain, but it is one of the most important control components for the human body. (MORE)

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In Education

# Is signum function a bijective function?

The signum function is defined as follows: f(x) = -1 if x < 0 = 0 if x=0 = 1 if x > 0 It is not one-to-one (bijective) as can be easility seen). f(2)=1 f(3)=…1 f(10)=1 and so on. (MORE)

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In Genetics

# Do all nerve cells have a neurilemma?

The neurilemma is the Schwann cell. This helps with regeneration of cells. The nerve cells in the brain do not have neurilemma and therefore, cannot regenerate.

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In Health

# How does the schwann cells form the myelin sheath and the neurilemma encasing the nerve processes?

The Schwann cells wrap themselves tightly around the axon like a jellyroll. During the wrapping process, the cytoplasm is squeezed from between adjacent layers of the Sc…hwann cell membranes, so that when the process is completed a tight core of plasma membrane material encompasses the axon. This wrapping is the myelin sheath. The Schwann cell nucleus and the bulk of its cytoplasm end up just beneath the outermost portion of its plasma membrane. This peripheral part of the Schwann cell and its exposed plasma membrane is the neurilemma. (MORE)