III-Nitride Self-assembled Nanowire Light Emitting Diodes and Lasers on (001) Silicon.

Substantial research is being devoted to the development of III-nitride light emitting diodes (LEDs) and lasers, which have numerous applications in solid state lighting. In particular, white LEDs play an increasingly important role in our daily lives. Current commercially available white LEDs are nearly all phosphor-converted, but these have some serious disadvantages. Planar quantum well (QW) devices on foreign substrates exhibit large threading dislocation densities, strong strain induced polarization field, and In-rich nanoclusters resulting in poor electron-hole wavefunction overlap, large emission peak shift with injection, and large efficiency drop at high injection currents in LEDs and large threshold current densities in lasers. The objective of this doctoral research is to investigate the prospects of self-assembled InGaN/GaN disks-in-nanowire (DNW) LEDs and lasers for solid state lighting. The research described here embodies a detailed study of the optical and structural characteristics of the nanowire heterostructures by varying the growth conditions and by surface passivation, and using the disks as the active region in high performance nanowire LEDs and gain medium in nanowire lasers on (001) silicon. Self-assembled InGaN/GaN DNWs are grown in a plasma-assisted molecular beam epitaxy (PA-MBE) system. Due to their large surface to volume ratio, the growth optimized and surface passivated DNWs on (001) silicon are relatively free of extended defects and have smaller polarization field resulting in higher radiative efficiencies. Blue-, green- and red-emitting DNW LEDs, with optimized nanowire densities, are demonstrated with reduced efficiency droop and smaller peak shift with injection. Phosphor-free white nanowire LEDs are realized by incorporating InGaN/GaN disks with different color emissions in the active region. The first ever monolithic edge-emitting electrically pumped green and red nanowire lasers on (001) silicon are demonstrated using DNWs as the gain media and are characterized by low threshold current densities of 1.76-2.88 kA/cm2, small peak shifts of 11-14.8 nm, large T0 of 234 K and large differential gain of 3x10-17 cm-2. Dynamic measurements performed on these lasers yield a maximum small signal modulation bandwidth of 5.8 GHz, extremely low value of chirp (0.8 Å) and a near-zero linewidth enhancement factor at the peak emission wavelength.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111490/1/shafat_1.pd

PROSES PEMBUATAN POMADE DARI MINYAK KELAPA MENGGUNAKAN ALAT SCREW PRESS (Process Of Making Pomade From Coconut Oil Using A Screw Press)

Mechanical pressingis a way ofextracting oilorgrease, especiallyfor materialsderivedfrom grains. How this is doneto separate theoilfromthe materiala highoil content(30-70 percent).Coconutisone kind of plantbelonging to thetribe ofnut-proposal (Arecaceae). All parts ofthe coconuttreecan be used, rangingfrom flowers, stems, stem, leaves, fruits, rootsand evencan beused. Coconut oilbasedfatty acidsare classifiedintoasanlauricoil, becausemostlargelauricacid contentwhen comparedwithother fattyacids. Pomadeis a kind ofhair oilmade fromoily substancesor similarmaterial fromwax(wax) used forstylingthe hair. Keyword: PressingMechanic, Coconut Oil, Pomad

DOUBLE AND TRIPLE BOUNCING SPINNING SOCCER BALL

The trajectories of soccer ball penalty kicks that strike one of the goal-posts while rolling along the surface are simulated and analyzed using conservation of linear and angular momenta. The reflected trajectories upon collisions with the goalpost are calculated and used to determine whether double or triple bounces take place. The analysis is iterated for a range of initial launch speeds, angular velocities, and normal and tangential coefficients of restitution of the goalpost-ball collisions. It is observed that double bounces can take place for almost any combination of the above parameters if the soccer ball strikes the appropriate narrow sectors of the first goalpost. The corresponding parameter ranges and impact areas are considerably more restricted for generating triple bounces. The angular velocity and coefficients of restitution are found to significantly influence the occurrence of multiple bounces

A comparison of the satiating properties of medium-chain triglycerides and conjugated linoleic acid in participants with healthy weight and overweight or obesity

Purpose Inconsistent evidence exists for greater satiety after medium-chain triglycerides (MCT) or conjugated linoleic acid (CLA) compared to long-chain triglycerides (LCT). Furthermore, the mechanisms are poorly understood and effects in people with a healthy weight and those with overweight/obesity have not been compared. This study aimed to compare appetite responses in these groups and examine the mechanisms behind any differences. Methods Fifteen participants with healthy weight (BMI: 22.7 ± 1.9 kg·m−2) and fourteen participants with overweight/obesity (BMI: 30.9 ± 3.9 kg·m−2) consumed a breakfast containing either 23.06 g vegetable oil (CON), 25.00 g MCT oil (MCT), or 6.25 g CLA and 16.80 g vegetable oil (CLA). Appetite, peptide YY (PYY), total ghrelin (TG), β-hydroxybutyrate, and gastric emptying (GE) were measured throughout. Energy intake was assessed at an ad libitum lunch and throughout the following ~ 36 h. Results Neither MCT nor CLA decreased ad libitum intake; however MCT decreased day 1 energy intake (P = 0.031) and the 48-h period (P = 0.005) compared to CON. MCT delayed GE (P ≤ 0.01) compared to CON, whereas CLA did not. PYY and TG concentrations were not different (P = 0.743 and P = 0.188, respectively), but MCT increased β-hydroxybutyrate concentrations compared to CON (P = 0.005) and CLA (P < 0.001). β-hydroxybutyrate concentrations were higher in participants with overweight/obesity (P = 0.009). Conclusion Consumption of MCT reduces energy intake in the subsequent 48 h, whereas CLA does not. Delayed gastric emptying or increased β-hydroxybutyrate concentrations may mediate this

Oral versus intubated feeding and the effect on glycaemic and insulinaemic responses, gastric emptying and satiety

Cephalic phase responses (CPR) are important in early initiation of digestion and maximal absorption of nutrients prior to ingestion. Bypassing CPR has been shown to have consequences on metabolic responses that may influence satiety. The aim of this study was to investigate if using gastric intubation to bypass oro-pharyngeal and oesophageal exposure would reduce CPR including insulin and blood glucose and whether these impact on gastric emptying and satiety. Ten male subjects were tested on 2 occasions, 3-7 days apart after an overnight fast, in randomized order. Subjects were cannulated and intubated with a gastric tube for both tests. For test one, subjects ate 400 ml soup with a spoon and for test two the soup was infused into the stomach at an equivalent rate. Subsequently measurements of glycaemic (GR) and insulinaemic responses (IR) from cannula samples, breath samples for measurement of gastric emptying using the [(13)C] sodium acetate breath test and visual analogue scales (VAS) for satiety were taken over 180 min. There were differences in IR over the first 15 min (Oral: 169.0 +/- 22.1; Gastric 124.1 +/- 18.8; t(9) = 2.67; p = 0.028) but no difference in GR. There were differences in gastric emptying half time (Oral: 85.0 +/- 2.7; Gastric 79.4 +/- 3.3; t(9) = 2.40; p = 0.04) and ascension time (Oral: 68.2 +/- 2.2; Gastric 64.0 +/- 2.2; t(9) = 2.57; p = 0.03) with food taking longer to empty from the stomach on the Oral test day than on the Gastric test day. There was no significant difference in the satiety ratings. This study demonstrated that bypassing oro-pharyngeal and oesophageal exposure decreases the normal physiological CPR with detriment to IR and gastric emptying

Dyeing studies with henna and madder: A research on effect of tin (II) chloride mordant

The present paper deals with the application of natural dyes extracted from powdered henna (Lawsonia inermis) leaves and madder (Rubia cordifolia) roots on woolen yarn and assessment of effect of stannous chloride mordant on dyeability, color characteristics, fastness properties and antifungal activity of dyed woolen yarn. Sixteen shades have been developed for the characterization of their color characteristics and fastness properties. The color strength (K/S value) has been found to be very good in all dyed woolen yarn samples. The color fastness with respect to light exposure, washing and rubbing was quite satisfactory for both henna as well as madder dyed samples. Henna leaves extract was found very effective against Candida glabrata both in solution as well as after application on wool substrate but no antifungal activity is reported in case of madder both in solution as well as on wool substrate

BIOMECHANICAL & PHYSIOLOGICAL CHARACTERISATION OF FOUR CYCLING POSITIONS

This study examined the effect of a change in body position on a selection of biomechanical and physiological variables affecting triathlon performance. Ten local triathletes, participated in this investigation. This study also introduces a novel, inexpensive method of calculating frontal projection area (FPA). FPA decreased a total of 31.6% as the athletes moved from the hoods position to the superman position. No changes in physiological performance variables were reported across the cycling positions. The superman position was found to elicit detrimental effects on peak sprint power output and body comfort. This data lends to the conclusion that the superman position does not offer a greater advantage to the triathlete

Chest wall schwannoma: Case report and a review of imaging findings

A chest wall schwannoma arises from peripheral nerve sheath Schwann cells of the intercostal nerves. We describe the presentation and imaging findings of a patient who presented with a chest wall swelling. The imaging findings were highly suspicious for a chest wall schwannoma and the histopathology confirmed the diagnosis following surgical excision. Imaging findings are reviewed in detail