Drop size in a liquid pulsed sieve-plate extraction column

Peer reviewedPublisher PD

Si-Based Germanium Tin Semiconductor Lasers for Optoelectronic Applications

Silicon-based materials and optoelectronic devices are of great interest as they could be monolithically integrated in the current Si complementary metal-oxide-semiconductor (CMOS) processes. The integration of optoelectronic components on the CMOS platform has long been limited due to the unavailability of Si-based laser sources. A Si-based monolithic laser is highly desirable for full integration of Si photonics chip. In this work, Si-based germanium-tin (GeSn) lasers have been demonstrated as direct bandgap group-IV laser sources. This opens a completely new avenue from the traditional III-V integration approach. In this work, the material and optical properties of GeSn alloys were comprehensively studied. The GeSn films were grown on Ge-buffered Si substrates in a reduced pressure chemical vapor deposition system with low-cost SnCl4 and GeH4 precursors. A systematic study was done for thin GeSn films (thickness \u3c 200 nm) with Sn compositions from 0 to 12%, and for thick GeSn films (thickness \u3e 400 nm) with Sn composition 5 to 17.5%. The room temperature photoluminescence (PL) spectra were measured that showed a gradual shift of emission peaks towards longer wavelength as Sn composition increases. Strong PL intensity and low defect density indicated high material quality. Moreover, the PL study of n-doped samples showed bandgap narrowing compared to the unintentionally p-doped (boron) thin films with similar Sn compositions. Finally, optically pumped GeSn lasers on Si with broad wavelength coverage from 2 to 3 μm were demonstrated using high-quality GeSn films with Sn compositions up to 17.5%. The achieved maximum Sn composition of 17.5% broke the acknowledged Sn incorporation limit using similar deposition chemistry. The highest lasing temperature was measured at 180 K with an active layer thickness as thin as 270 nm. The unprecedented lasing performance is due to the achievement of high material quality and a robust fabrication process. The results reported in this work show a major advancement towards Si-based electrically pumped mid-infrared laser sources for integrated photonics

HAEMATOLOGICAL PARAMETERS IN EXOTIC COWS DURING GESTATION AND LACTATION UNDER SUBTROPICAL CONDITIONS

Seventy Holstein-Friesian and Jersey cows of different ages kept at the Livestock Experiment Station, Bhunikey (Pattoki), district Kasur, Pakistan were used for this study. These cows were divided into seven groups having 10 animals in each group. Group numbers 1 to 7 were named as pregnant heifers, pregnant lactating cows, non-pregnant dry cows, non-pregnant heifers, parturient cows, pregnant dry cows and non-pregnant lactating cows, respectively. Blood samples from all the animals were collected and haematological values were recorded, using routine haematological procedures. The highest Hb concentration (11.32 ± 0.32 gm/dl) was recorded in group-4, while the lowest (9.24 ± 0.35 gm/dl) was observed in group-7. The highest RBCs count and PCV (6.18 ± 0.47 x 106/µl and 35.51 ± 1.51%) were recorded in group-4 and the lowest (4.55 ± 0.26 x 106/µl and 29.23 ± 1.09%) values were observed in group-6. The highest MCV, MCH and MCHC (65.26 ± 1.96 fl, 23.50 ± 1.31 pg and 35.75 ± 0.99 gm/dl) were noted in group-5 and the lowest (55.16 ± 1.72 fl, 16.77 ± 1.14 pg and 30.09 ± 1.15 gm/dl) were noted in group-2. The highest ESR (7.60 ± 1.15 mm/24 hours) was recorded in group-6 and the lowest (4.89 ± 0.40 mm/24 hours) values were observed in group-5. The highest WBCs count (9.43 ± 1.15 x 103/µl) was observed in group-1 and the lowest (6.35 ± 0.72 x 103/µl) was recorded in group-5. Amongst DLC, highest (P<0.05) lymphocyte count (69.10 ± 2.55%) was observed in group-4, while lowest count (56.70 ± 5.16%) was in group-5. The differences between monocyte, neutrophil, eosinophil and basophil counts in all the groups were statistically non-significant

A New Learning Theory-based Framework for Combining Flow State with Game Elements to Promote Engagement and Learning in Serious Games

Serious games (SGs) are seen as a clear aid and a potential technique for motivating learners to engage in active and beneficial learning. The creation of SGs is a difficult task. Learning theory, learning aspects (pedagogy and learning materials), and game design are three cross-disciplinary issues related to successful SG design. Numerous studies have looked at this matter and provided guidelines and frameworks for resolving important research concerns. We discovered, however, that research hardly ever discusses the roots of learning theory in SGs. Unfortunately, designing proper SGs is still more of an art than a science. The science of SGs has to be developed on a strong theoretical basis. By illustrating how SGs may be understood from several theoretical viewpoints in learning theory and going through a number of core game design elements that are necessary for successful learning, this paper makes an attempt to solve this issue. Then, in order to encourage engagement and learning in SG contexts, we provide a new framework for the design and development of SG models that makes it easier to combine flow state with such game elements. The agile software process model serves as the basis for the development process in our system. The Unified Modeling Language was used to model prototypes and diagrams. A case study entitled One day without the use of computer-based intervention technologies was used to demonstrate the effectiveness of the proposed framework

Differential effects of anti-B7-1 and anti-B7-2 monoclonal antibody treatment on the development of diabetes in the nonobese diabetic mouse.

Insulin-dependent diabetes mellitus (IDDM) is thought to be an immunologically mediated disease resulting in the complete destruction of the insulin-producing islets of Langerhans. It has become increasingly clear that autoreactive T cells play a major role in the development and progression of this disease. In this study, we examined the role of the CD28/B7 costimulation pathway in the development and progression of autoimmune diabetes in the nonobese diabetic (NOD) mouse model. Female NOD mice treated at the onset of insulitis (2-4 wk of age) with CTLA4Ig immunoglobulin (Ig) (a soluble CD28 antagonist) or a monoclonal antibody (mAb) specific for B7-2 (a CD28 ligand) did not develop diabetes. However, neither of these treatments altered the disease process when administered late, at &gt; 10 wk of age. Histological examination of islets from the various treatment groups showed that while CTLA4Ig and anti-B7-2 mAb treatment blocked the development of diabetes, these reagents had little effect on the development or severity of insulitis. Together these results suggest that blockade of costimulatory signals by CTLA4Ig or anti-B7-2 acts early in disease development, after insulitis but before the onset of frank diabetes. NOD mice were also treated with mAbs to another CD28 ligand, B7-1. In contrast to the previous results, the anti-B7-1 treatment significantly accelerated the development of disease in female mice and, most interestingly, induced diabetes in normally resistant male mice. A combination of anti-B7-1 and anti-B7-2 mAbs also resulted in an accelerated onset of diabetes, similar to that observed with anti-B7-1 mAb treatment alone, suggesting that anti-B7-1 mAb's effect was dominant. Furthermore, treatment with anti-B7-1 mAbs resulted in a more rapid and severe infiltrate. Finally, T cells isolated from the pancreas of these anti-B7-1-treated animals exhibited a more activated phenotype than T cells isolated from any of the other treatment groups. These studies demonstrate that costimulatory signals play an important role in the autoimmune process, and that different members of the B7 family have distinct regulatory functions during the development of autoimmune diabetes

REPRODUCTIVE EFFICIENCY OF JERSEY COWS UNDER SUBTROPICAL CONDITIONS OF THE PUNJAB

Various parameters of reproductive efficiency of Jersey cows kept at the Livestock Experiment Station, Bhunikey (Pattoki), District Kasur, for the period from 1991 to 2000 were studied. The average values of age at maturity and age at first calving were 615.48 ± 8.23 and 926.48 ± 10.29 days, respectively and the differences of these parameters during different seasons of birth were statistically non-significant. The average calving to first insemination interval, service period and calving interval were 86.65 ± 1.71, 152.66 ± 4.85 and 430.15 ± 4.87 days, respectively. The differences of calving to first insemination interval among cows calved during different seasons were statistically non-significant. But the differences of calving to first insemination interval during 1st lactation were significant (P<0.05) with those of 6th, 7th and 9th lactations. Service period and calving interval in the Jersey cows calved during humid hot season were significantly (P<0.05) shorter as compared to those of cows calved during dry hot and spring seasons. Effect of parity on the service period was non-significant, but the effect of parity on the calving interval was significant (P<0.05), when the difference of calving interval during 7th and 8th lactation was compared. The average number of services per conception was 2.81 ± 0.09. The effect of parity on the number of services per conception was significant (P<0.05). The average gestation period was 277.63 ± 0.21 days. Higher gestation period was observed in cows carrying male calves than those carrying female calves (P<0.05). The frequency of calvings during winter, spring, dry hot, humid hot and autumn seasons was 19.32, 19.20, 9.79, 33.25 and 18.44 percent, respectively

Screen time is associated with adiposity and insulin resistance in children

Higher screen time is associated with type 2 diabetes (T2D) risk in adults, but the association with T2D risk markers in children is unclear. We examined associations between self-reported screen time and T2D risk markers in children. Survey of 4495 children aged 9-10 years who had fasting cardiometabolic risk marker assessments, anthropometry measurements and reported daily screen time; objective physical activity was measured in a subset of 2031 children. Compared with an hour or less screen time daily, those reporting screen time over 3 hours had higher ponderal index (1.9%, 95% CI 0.5% to 3.4%), skinfold thickness (4.5%, 0.2% to 8.8%), fat mass index (3.3%, 0.0% to 6.7%), leptin (9.2%, 1.1% to 18.0%) and insulin resistance (10.5%, 4.9% to 16.4%); associations with glucose, HbA1c, physical activity and cardiovascular risk markers were weak or absent. Associations with insulin resistance remained after adjustment for adiposity, socioeconomic markers and physical activity. Strong graded associations between screen time, adiposity and insulin resistance suggest that reducing screen time could facilitate early T2D prevention. While these observations are of considerable public health interest, evidence from randomised controlled trials is needed to suggest causality. [Abstract copyright: Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The Relation between Fructose-Induced Metabolic Syndrome and Altered Renal Haemodynamic and Excretory Function in the Rat

This paper explores the possible relationships between dietary fructose and altered neurohumoral regulation of renal haemodynamic and excretory function in this model of metabolic syndrome. Fructose consumption induces hyperinsulinemia, hypertriglyceridaemia, insulin resistance, and hypertension. The pathogenesis of fructose-induced hypertension is dubious and involves numerous pathways acting both singly and together. In addition, hyperinsulinemia and hypertension contribute significantly to progressive renal disease in fructose-fed rats. Moreover, increased activity of the renin-angiotensin and sympathetic nervous systems leading to downregulation of receptors may be responsible for the blunted vascular sensitivity to angiotensin II and catecholamines, respectively. Various approaches have been suggested to prevent the development of fructose-induced hypertension and/or metabolic alteration. In this paper, we address the role played by the renin-angiotensin and sympathetic nervous systems in the haemodynamic alterations that occur due to prolonged consumption of fructose

Shape Evasion: Preventing Body Shape Inference of Multi-Stage Approaches

Modern approaches to pose and body shape estimation have recently achieved strong performance even under challenging real-world conditions. Even from a single image of a clothed person, a realistic looking body shape can be inferred that captures a users' weight group and body shape type well. This opens up a whole spectrum of applications -- in particular in fashion -- where virtual try-on and recommendation systems can make use of these new and automatized cues. However, a realistic depiction of the undressed body is regarded highly private and therefore might not be consented by most people. Hence, we ask if the automatic extraction of such information can be effectively evaded. While adversarial perturbations have been shown to be effective for manipulating the output of machine learning models -- in particular, end-to-end deep learning approaches -- state of the art shape estimation methods are composed of multiple stages. We perform the first investigation of different strategies that can be used to effectively manipulate the automatic shape estimation while preserving the overall appearance of the original image

Comparison of explosion characteristics of Colombian and Kellingley coal

Coal continues to be one of the main fuels used for generation of energy in the UK. Despite government’s plans to decarbonise the energy sector in order to meet GHG emission targets, co-firing of coal and biomass is attractive due to the low investment required and since gas prices remain high, the consumption of coal is still considerable in power generation. Pulverised coal has been known to pose explosion risks since the 19th century. The objective of the present work was to compare the explosibility of two coal samples used in UK power stations which potentially can be used co-fired with biomass. Both samples of coal were fully characterised for their chemical composition as well as particle size and morphology. The 1m3 ISO explosion vessel was used to determine the explosion characteristics: deflagration index (Kst), maximum explosion pressure (Pmax) and minimum explosible concentration (MEC). Flame speeds were also measured. The remaining residues after explosion were also analysed. The results were compared to the explosion characteristics of other types of coal available in the literature. Despite the very similar composition of both fuels, the reactivity of Colombian coal was much higher, with a Kst value of 129 barms-1 as opposed to 73 barms-1 for Kellingley coal (Fig.1). There was significant difference between these two coals as the surface area of Colombian coal was 5 times higher than that of Kellingley coal. There was little difference in the elemental composition, but Colombian coal contained more volatiles and less ash. Thus the results indicate a strong impact of particle surface area and volatile content on the reactivity of coal