Morphology and Structure of Hair

فهرست عناوین اصلی در این پاورپوینت

فهرست عناوین اصلی در این پاورپوینت

● Hairs & Fibers
● Morphology and Structure of Hair
● Morphology: Cuticle
● Morphology: Cortex
● Morphology: Medulla
● Medullary Index
● Medullae of Different Species
● Medulla of Different Species
● Forensic Analysis of Medulla
● Identification and Comparison of Hair
● Can the racial origin of hair be determined?
● Hair from different parts of the body
● Beard, arm, and pubic hairs
● Differences between animal hairs and human hairs
● Fibers: Natural
● Man-Made Fibers
● Man-Made Fibers Con’t
● ID and Comparison of Man-Made Fibers

نوع زبان: انگلیسی حجم: 2.83 مگا بایت
نوع فایل: اسلاید پاورپوینت تعداد اسلایدها: 23 صفحه
سطح مطلب: نامشخص پسوند فایل: ppt
گروه موضوعی: زمان استخراج مطلب: 2019/06/07 09:28:27

لینک دانلود رایگان لینک دانلود کمکی

اسلایدهای پاورپوینت مرتبط در پایین صفحه

عبارات مهم استفاده شده در این مطلب

عبارات مهم استفاده شده در این مطلب

hair, ., human, animal, fiber, medullum, make, scale, diameter, shape, comparison, find,

توجه: این مطلب در تاریخ 2019/06/07 09:28:27 به صورت خودکار از فضای وب آشکار توسط موتور جستجوی پاورپوینت جمع آوری شده است و در صورت اعلام عدم رضایت تهیه کننده ی آن، طبق قوانین سایت از روی وب گاه حذف خواهد شد. این مطلب از وب سایت زیر استخراج شده است و مسئولیت انتشار آن با منبع اصلی است.

https://www.strongnet.org/cms/lib/OH01000884/Centricity/Domain/307/HairsandFiber09-10.ppt

در صورتی که محتوای فایل ارائه شده با عنوان مطلب سازگار نبود یا مطلب مذکور خلاف قوانین کشور بود لطفا در بخش دیدگاه (در پایین صفحه) به ما اطلاع دهید تا بعد از بررسی در کوتاه ترین زمان نسبت به حدف با اصلاح آن اقدام نماییم. جهت جستجوی پاورپوینت های بیشتر بر روی اینجا کلیک کنید.

عبارات پرتکرار و مهم در این اسلاید عبارتند از: hair, ., human, animal, fiber, medullum, make, scale, diameter, shape, comparison, find,

مشاهده محتوای متنیِ این اسلاید ppt

مشاهده محتوای متنیِ این اسلاید ppt

hairs fibers morphology and structure of hair morphology cuticle protective coating made of overlapping scales produce a characteristic pattern scales always point toward tip of hair not useful in individualizing human hair can be used for species identification http www.pg.com science haircare hair twh ۳۵ hair twh ۳۵ ۲.jpg morphology cortex made of spindle shaped cells aligned in a regular array parallel to the length of the hair embedded with pigment granules that give hair its color the color shape and distribution of the granules provide points for forensic comparison www.pg.com science haircare hair twh ۵۹.htm morphology medulla canal like structure of cells that runs through the center of the cortex pg. ۵۳ medullary index measure of the diameter of the medulla relative to the diameter of the hair shaft usually expressed as a fraction humans medullary index ۱ ۳ animals medullary index ۱ ۲ medullae of different species medulla of different species forensic analysis of medulla presence of medulla varies quite a bit even hair to hair human head hairs generally have no medulla or may be fragmented ones except mongoloid asian race whose medulla is usually continuous most animals have medulla that is continuous or interrupted the shape of the medulla can help identify a species examples most animals and humans cylindrical cats pearl shape deer spherical occupying whole hair shaft identification and comparison of hair morphological characteristics do not allow individualization of a human hair to any single head or body hair when collected with an adequate number of standards references can provide strong circumstantial evidence scale structure medullary index and medullary shape are most often used for hair comparison evidential value lies with degree of probability associated with a questioned hair and an particular individual ۱۱ percent of all morphological hair matches are generally found to be non matches—meaning microscopic hair comparisons are presumptive in nature—must be confirmed by dna comparisons can the racial origin of hair be determined forensic terms caucasian negroid mongoloid mongoloid has continuous medullae caucasian has even distribution of pigment in cortex negroid has unevenly distributed pigment. hair from different parts of the body scientists distinguish ۶ types of hair on the human body head hair eyebrows eyelashes beard mustache underarm body hair and pubic hair eye hairs are usually saber like and stubby facial hairs have a coarse diameter and the medulla may be doubled underarm hairs resemble pubic hairs but are less wiry pubic hairs have a coarse diameter buckling is present and the medulla is continuous when present beard arm and pubic hairs differences between animal hairs and human hairs there are three basic scale structures that make up the cuticle—coronal crown like spinous petal like and imbricate flattened . combinations and variations of these types are possible. differences between animal hairs and human hairs the coronal or crown like scale pattern is found in hairs of very fine diameter and resemble a stack of paper cups. coronal scales are commonly found in the hairs of small rodents and bats but rarely in human hairs. differences between animal hairs and human hairs spinous or petal like scales are triangular in shape and protrude from the hair shaft. they are found at the proximal region of mink hairs and on the fur hairs of seals cats and some other animals. they are never found in human hairs. http www.fbi.gov hq lab fsc backissu jan۲ ۴ research ۲ ۴ ۱ research ۱b.htm differences between animal hairs and human hairs the imbricate or flattened scales type consists of overlapping scales with narrow margins. they are commonly found in human hairs and many animal hairs. differences between animal hairs and human hairs human hairs are generally consistent in color and pigmentation throughout the length of the hair shaft whereas animal hairs may exhibit radical color changes in a short distance called banding. the distribution and density of pigment in animal hairs can also be identifiable features. the pigmentation of human hairs is evenly distributed or slightly more dense toward the cuticle whereas the pigmentation of animal hairs is more centrally distributed although more dense toward the medulla. the medulla when present in human hairs is amorphous in appearance and the width is generally less than one third the overall diameter of the hair shaft. the medulla in animal hairs is normally continuous and structured and generally occupies an area of greater than one third the overall diameter of the hair shaft. fibers natural derived entirely from animal or plant sources most prevalent plant fiber is cotton. its widespread use has made its evidential value almost meaningless cotton has a ribbon like shape with twists at regular intervals animal sources include sheep wool goats mohair cashmere and many other sources http www.swicofil.com images cotton microscopic.jpg http www.e۴s.org.uk textilesonline content ۶library report۱ images microscope ۲.gif wool cotton man made fibers fibers derived from either natural or synthetic polymers the fibers are made by forcing polymeric material through the holes of a spinneret rayon and then nylon were the first two man made fibers year ۱۹۱۱ http www.naturalvisions.co.uk pictures thumbnail xmic ۲۱ ۱xx.jpg man made fibers con’t regenerated fibers made from regenerated cellulose wood or cotton pulp include such fibers as rayon acetate and triacetate synthetic fibers currently manufactured made from synthetic chemicals called polymers include such fibers as nylons polyesters and acrylics id and comparison of man made fibers fabrics that can be fitted together at their torn edge are easy to match microscopic comparison of color and diameter comparison of lengthwise striations and pitting on the surface of a fiber the shape of the fiber—ex. wayne williams case cross sections are generally helpful note combined factors of color size shape microscopic appearance chemical composition and dye content make it very unlikely to find two different people wearing identical fabrics …

کلمات کلیدی پرکاربرد در این اسلاید پاورپوینت: hair, ., human, animal, fiber, medullum, make, scale, diameter, shape, comparison, find,

این فایل پاورپوینت شامل 23 اسلاید و به زبان انگلیسی و حجم آن 2.83 مگا بایت است. نوع قالب فایل ppt بوده که با این لینک قابل دانلود است. این مطلب برگرفته از سایت زیر است و مسئولیت انتشار آن با منبع اصلی می باشد که در تاریخ 2019/06/07 09:28:27 استخراج شده است.

https://www.strongnet.org/cms/lib/OH01000884/Centricity/Domain/307/HairsandFiber09-10.ppt

  • جهت آموزش های پاورپوینت بر روی اینجا کلیک کنید.
  • جهت دانلود رایگان قالب های حرفه ای پاورپوینت بر روی اینجا کلیک کنید.

رفتن به مشاهده اسلاید در بالای صفحه


پاسخی بگذارید

نشانی ایمیل شما منتشر نخواهد شد. بخش‌های موردنیاز علامت‌گذاری شده‌اند *