Application of various types of alumina and nano-γ-alumina sulfuric acid in the synthesis of α-aminonitriles derivatives: comparative study

An efficient and green protocol for the synthesis of α-aminonitrile derivatives by one-pot reaction of different aldehydes with amines and trimethylsilyl cyanide has been developed using natural alumina, alumina sulfuric acid (ASA), nano-g-alumina, nano-g-alumina sulfuric acid (nano-g-ASA) under microwave irradiation and solvent-free conditions. The advantages of methods are short reaction times, high yields, milder conditions and easy work up. The catalysts can be recovered for the subsequent reactions and reused without any appreciable loss of efficiency. KEY WORDS: Nano-g-alumina, Nano-g-alumina sulfuric acid, Green synthesis, Microwave irradiation, α-aminonitriles derivatives Bull. Chem. Soc. Ethiop. 2014, 28(3), 441-450.DOI: http://dx.doi.org/10.4314/bcse.v28i3.1

Assessing the validity of western measurement of online risks to children in an Asian context

Before the advent of the Internet, television with limited channels was the only media choice that most children were exposed to, and took place under family supervision. Children’s television viewing was controllable and the risks were limited to watching sexual and violent content. Nowadays, children are surrounded by a variety of digital media and are exposed to many different risks, many of which are still unknown and under-researched. For many children, the Internet is fully integrated into their daily lives, along with the potential risks. The present study aimed to (i) describe the level of risks children are exposed to, and (2) test the measurement validity of a total of 45 items assessing nine scales online risky behavior in children were adapted from studies carried out in Europe and the United States. The study comprised 420 school going children aged 9, 11, 13, 14, and 16 studying in Malaysia. Descriptive analyses showed that children were more exposed to ‘unwanted exposure to pornography’ and less to ‘conduct risk’. Boys and older children were more exposed to the risks compared to girls and younger children. The study validated five dimensions (inappropriate materials, sexting, contact-related risks on, risky online sexual behavior, and bullying/being bullied) assessing children’s online risky behavior by using exploratory and confirmatory factor analyses. Further research is needed to investigate the measurement of children’s online risk, since the scales developed in Europe and the United States are not wholly suitable to an Asian context

The effects of alfalfa particle size and acid treated protein on ruminal chemical composition, liquid, particulate, escapable and non escapable phases in Zel sheep

This study was conducted to investigate the effects of alfalfa particle size (long vs. fine) and canola meal treated with hydrochloric acid solution (untreated vs treated) on ruminal chemical composition, liquid, particulate, escapable and non escapable phases in Zel sheep. Four ruminally cannulated sheep received a mixed diet (% of dry matter) consisting of 23.73 alfalfa, 8.70 canola meal, 39.56 wheat straw, 13.45 beet pulp and 13.45 barley grain and 1 mineral-vitamin mixture. The experimental design was a 4 × 4 Latin square with 22-days periods. The diet was offered twice daily (09:00 and 21:00 h). The rumens were evacuated manually at 3, 7.5 and 12 h post-feeding and total ruminal contents were separated into mat and liquids. Dry matter weight distribution of total recovered particles was determined by a wetsieving procedure and used to partition ruminal mat and liquids among percentage of large (≥ 6.35 mm), medium (< 6.35 and ≥ 1.18 mm), and small (< 1.18 and ≥ 0.5 mm) particles. Lyophilized ruminal digesta were analyzed for chemical composition especially for CP, NDF and EE. No interactions (P > 0.05) between dietary particle size and acid level were observed for ruminal chemical composition, liquid, particulate, escapable and non escapable phase. Treatment of canola meal and increase of particle size reduced the values of CP. Generally, with increase in time after feeding, the values of each nutrient decreased. Particle size and time post-feeding had a pronounced effect on the distribution of different particle fractions, whereas acid level did not influence it. With increase in time after feeding, percentage of particles ≥ 6.35 mm decreased, whereas the percentage of particles < 6.35 mm increased, illustrating intensive particle breakdown in the reticulo-rumen. Different particle size and time post-feeding had pronounced effect on total mass of ruminal digesta, ruminal mat and liquid part, in which fine particles and 12 h post feeding caused the lowest rumen mat. Time post feeding and acid level did not influence the values of pH significantly, whereas with increase in particle size, the values of pH increased.Key words: Canola meal, particle size, rumen mat, escapable, non escapable phase

Dual band, Miniaturized Permittivity Measurement Sensor with Negative-Order SIW Resonator

A novel dual band, highly sensitive Substrate Integrated Waveguide (SIW) sensor for permittivity measurements is presented. A pair of modified Complementary Split Ring Resonators (CSRRs) is etched on SIW surface. CSRRs are located in the center of SIW, where the electric field distribution is high so that the coupling be maximized. The coupling between the SIW and the CSRRs as well as the adjacent CSRRs results in two notches in transmission coefficient. These notches vary with the dielectric loading on the sensor. The ratio of a notch variation to the load permittivity variation determines the sensitivity of proposed sensor. Two sensitivities proportional to two notches are provided. Normalized sensitivities from both notches show identical values. Therefore, any environmental effect have the same variation on the TZs. This demonstrates the potential of the proposed sensor for differential operation that can mitigate the effect of environmental condition. The size of the proposed sensor is small as the inductive and the capacitive effects of CSRRs forced the SIW to operate below the cut off frequency at negative-order-resonance mode. All design steps including SIW design, CSRRs design and modified CSRRs effects are presented in details. The sensor operation principle is described through an equivalent circuit model as well as simulation results. The experimental results indicates that the normalized sensitivity is 3.4% which is much higher than similar sensors. The prototype sensor size (27.8 x 18.4 x 0.508 mm(3)) is smaller than those reported in the literature

EFFECT OF DIET DILUTION IN THE STARTER PERIOD ON PERFORMANCE AND CARCASS CHARACTERISTICS OF BROILER CHICKS

The effect of energy and protein dilution in the starter period (8 to 14 days) of age, on performance and carcass characteristics of 360 Arian male chicks was studied in a completely randomised design. This experiment consisted of 6 treatments, 4 replicates, with 15 chicks per replicate. In order to dilute the diets six levels (0, 4, 8, 12, 16, and 20) percent of ground wood charcoal was used. Chicks were fed with starter and grower diet from 15 to 21 and 22 to 42 days of age respectively. During the experiment feed intake, body weight gain, feed conversion ratio were measured weekly. Mortality was measured throughout the experiment. At 43 day of age 4 chicks each treatment was selected and carcass characteristics were measured. The results indicated that dilution of diet from 8 to 14 days of age increased feed intake in this period but the differences were not signifi cant. With increasing dilution rate body weight gain of chicks signifi cantly decreased in comparison to control group (P< 0.05). Due to compensatory growth after restricted period, there was not signifi cant difference in body weight among restricted and control groups at 42 days of age. There was not signifi cant difference among the treatments for feed conversion ratio in whole period of the experiment (8 to 42 day). Similarly, there was not signifi cant difference among the treatments for caloric conversion ratio in whole period of the experiment (8 to 42 day). Mortality rate in restricted groups was signifi cantly lower than control group (P<0.05). Diet dilution hadn’t signifi cant effect on carcass, breast meat, drumsticks, thighs, liver, intestine, abdominal fat percentages. The results of the present study indicated that broiler chicks could withstand a 7-day period (from 8 to 14 days) feed restriction with ground wood charcoal in early age without loss in performance

Investigating 2d and 3d convolutions for multitemporal land cover classification using remote sensing images

With the availability of large amounts of satellite image time series (SITS), the identification of different materials of the Earth's surface is possible with a high temporal resolution. One of the basic tasks is the pixel-wise classification of land cover, i.e.The task of identifying the physical material of the Earth's surface in an image. Fully convolutional neural networks (FCN) are successfully used for this task. In this paper, we investigate different FCN variants, using different methods for the computation of spatial, spectral, and temporal features. We investigate the impact of 3D convolutions in the spatial-Temporal as well as in the spatial-spectral dimensions in comparison to 2D convolutions in the spatial dimensions only. Additionally, we introduce a new method to generate multitemporal input patches by using time intervals instead of fixed acquisition dates. We then choose the image that is closest in time to the middle of the corresponding time interval, which makes our approach more flexible with respect to the requirements for the acquisition of new data. Using these multi-Temporal input patches, generated from Sentinel-2 images, we improve the classification of land cover by 4% in the mean F1-score and 1.3% in the overall accuracy compared to a classification using mono-Temporal input patches. Furthermore, the usage of 3D convolutions instead of 2D convolutions improves the classification performance by a small amount of 0.4% in the mean F1-score and 1.2% in the overall accuracy

Association between two common transitions of H2BFWT gene and male infertility: a case�control, meta, and structural analysis

H2BFWT is one of the testis‐specific histones that plays a fundamental role in spermatogenesis, and single nucleotide polymorphisms (SNPs) in this gene may result in male infertility. This study aimed to investigate the association between −9C>T and 368A>G transitions of H2BFWT gene and male infertility through a case–control, meta‐analysis, and a bioinformatics approach. In this case–control study, 490 subjects including 240 idiopathic infertile men and 250 healthy controls were included. The −9C>T and 368A>G SNPs genotyping were performed by a PCR–RFLP method. To find eligible studies for meta‐analysis, we searched valid scientific databases. The odds ratios with 95% confidence intervals were estimated to find the strength of these associations. Furthermore, the influences of two common transitions on the molecular features of H2BFWT were assessed by in silico tools. Our case–control data revealed that −9C>T is not associated with male infertility. But, there was a significant association between 368A>G and male infertility. In the meta‐analysis, five eligible studies were included. Our data revealed significant associations between −9C>T, 368A>G, and male infertility in overall and stratified analyses. Moreover, structural analysis showed that 368A>G could affect the protein structure (SNAP prediction: non‐neutral, score: 42, expected accuracy: 71%; SIFT prediction: deleterious, score: −2.55), while −9C>T may affect the binding nucleotide in the promoter region. Based on these findings, two aforementioned polymorphisms were associated with increased risk of male infertility. However, studies with larger sample size and different ethnicities are needed to obtain more accurate conclusions

Foreign Bodies: Aspirated or Ingested? A Report of Two Unusual Cases

Introduction: The diagnosis of foreign bodies in the upper aerodigestive tract is usually straightforward but sometimes it can be delayed or the location of esophageal and upper airway foreign bodies can be mistakenly interchanged. Case Report: We present two interesting cases that caused diagnostic challenges which could have led to serious complications if a greater delay in diagnosis had occurred. Conclusion: In order to diagnose upper aerodigestive tract foreign bodies without delay, a careful history and physical examination with proper X-rays are helpful