Surface-active solid lipid nanoparticles as Pickering stabilizers for oil-in-water emulsions

Oil-in-water (O/W) emulsions solely stabilized by surface-active solid lipid nanoparticles (SLNs) were developed. The SLNs were generated by quench-cooling hot O/W nanoemulsions consisting of 7.5% glyceryl stearyl citrate (GSC) dispersed in water. Their initial volume-weighted mean particle diameter (～152 nm) and zeta potential (ca.-49 mV) remained unchanged for 24 weeks. O/W emulsions (oil phase volume fraction: 0.2) containing 7.5% (w/w) GSC SLNs in the aqueous phase were kinetically-stable for 12 weeks and did not visually phase-separate over 24 weeks. The O/W emulsions generated with solid-state GSC SLNs had a volume-weighted mean oil droplet diameter of ～459 nm and a zeta potential of ca.-43 mV. Emulsion microstructure evaluated with TEM revealed dispersed oil droplets sparsely covered with adsorbed Pickering-type SLNs as well aggregated SLNs present in the continuous phase. Gradual emulsion destabilization resulted from GSC SLN dissolution during the experimental timeframe. Overall, surface-active SLNs developed via nanoemulsions effectively kinetically stabilized O/W emulsions.     

Sorption behavior of biodegradable polyurethanes with carbohydrate crosslinkers

Polyether–polyurethanes (PUs) with a series of carbohydrate crosslinkers: monosaccharide (glucose), disaccharide (fructose) and polysaccharide (starch), were synthesized. The kinetics of swelling was studied in industrially important solvents like toluene, xylene and chlorobenzene. The R value and diol / triol ratio were varied to study the effect on crosslink density and sorption. It was observed that the swelling extent increased with increasing concentration of crosslinker in the polymer. Interestingly the effect of diisocyanate concentration on extent of sorption varied with the type of carbohydrate used for crosslinking. Considering the effect of diisocyanate concentration, the PUs containing disaccharide sucrose showed greater solvent uptake. Though the sorption behaviours were different, the solubility parameters of all PUs were the same irrespective of the type and concentration of the crosslinkers. All the PUs were observed to be biodegradable with glucose containing PUs exhibiting highest weight loss. Scanning electron microscope revealed absence of phase segregation in all the PU systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

“竹纤维”纺织品真相探究

竹子 竹子枝干挺拔高大,生长速度快,是禾本科多年生木质化植物,一般生长在亚洲和印度洋、太平洋岛屿等热带或温热带地区,也有较少的竹类生长在美国南部,属于青篱竹属.竹子喜欢湿热的环境所以经常可以看到河边或湿地附近生长着茂密的竹林.据统计,竹子共有91个属,品种超过1 000个.     

One pot synthesis of TiO2:Eu3+ hierarchical structures as a highly specific luminescent sensing probe for the visualization of latent fingerprints

In the present work, TiO₂:Eu³⁺ (1 mol%–11 mol%) nano powders (NPs) were prepared via a facile one-pot hydrothermal method by using Epigallocatechin Gallate (EGCG) as bio-surfactant. The optimized TiO₂:Eu³⁺ (5 mol%) NPs can be used as fluorescent labeling agent for visualizing of latent fingerprints (LFPs) on various porous and non-porous surfaces. The obtained results exhibit well defined ridge details with high sensitivity, selectivity, and low background hindrance which show greater advantages as compared to conventional powders. We demonstrated the viability of high-performance security labels thorough excellent luminescence for practical anti-mimetic applications. Morphology of the prepared samples is highly dependent on pH, concentration of the bio-surfactant, temperature and time durations. Photoluminescence (PL) emission spectra exhibit intense red emission at ～ 615 nm due to electric dipole transition (⁵D₀→⁷F₂). Photometric (CIE and CCT) results clearly show the intense warm red emission of the optimized samples. Therefore, this work offers a superior and universal luminescent label, which can be applied to visualize miniature LFPs particulars for individualization and consequently display great prospective in forensic investigation.     

Analysis of Rain Attenuation Models for South East Asia Countries

This paper presents an analysis of experimental data compared with existing rain attenuation prediction models, namely, the Yamada, R&K, Crane, DAH and ITU models, which have been previously used in satellite communication systems. The experimental data were measured at the Universiti Sains Malaysia, Penang in the northern region of Peninsular Malaysia from 2007 to 2009 by receiving a Ku-band signal from the satellite SuperBird-C (geostationary at 144 °E). Data from Nigeria, Kenya, Indonesia, and PNG were obtained from the respective countries’ researchers. The DAH and ITU models were recommended as the most suitable models. The recommendation was made based on the model’s good performance compared with the measured data from the selected tropical countries.     

Assessment of nutritional status of children under five years of age, pregnant women, and lactating women living in relief camps after the tsunami in Sri Lanka

BACKGROUND: A strong earthquake that hit Aceh on December 26, 2004, triggered a powerful tsunami, resulting in an unprecedented catastrophe in Sri Lanka. The initial phase of the disaster was marked by limited access to food coupled with an inadequate supply of safe water and poor environmental hygiene and sanitation, all of which placed children at increased risk for undernutrition. OBJECTIVE: To assess the nutritional status of children under five years of age, pregnant women, and lactating women residing in 40 relief camps after the tsunami. METHODS: A cross-sectional, 30-cluster study was performed. Thirty children under five from each cluster (camp) and all pregnant and lactating women in selected camps were studied. Data were collected by interviews with the primary caregivers of the children, interviews with key informants in the camps, direct observation, and focus group discussions with mothers. Weight, height, or length was measured on children and pregnant women. Mid-upper-arm circumference of lactating women was measured. RESULTS: A total of 878 children were assessed, of whom 16.1%, 20.2%, and 34.7% were wasted, stunted, and underweight, respectively. The prevalence of each indicator was higher in boys than in girls. During the 2 weeks before the survey, 69.5% of the children had acute respiratory tract infections and 17.9% had diarrhea. Although the general food distribution was well in place, the food supply lacked diversity, and 70.9% of the children did not get appropriate supplementary food. The prevalence of undernutrition among pregnant women (n = 168) was 37%. Thirty-one percent of lactating women (n = 97) were underweight, and 20% were overweight. CONCLUSIONS: The prevalence of both acute and chronic undernutrition among children in the camps is significantly higher than the national Sri Lankan average. There is a need to establish nutritional surveillance systems to monitor the nutritional status of displaced and nondisplaced children and mothers.     

Prevalence of challenging nutritional problems among adolescents in Sri Lanka

BACKGROUND: Although 21% of the population of Sri Lanka consists of adolescents, studies of nutritional status among this group are limited. OBJECTIVE: To assess nutritional problems and dietary and activity patterns among adolescents in Sri Lanka. METHODS: A nationally representative cross-sectional study was conducted on 6,264 adolescents 10 to 15 years of age. All subjects were clinically examined for Bitot's spots, and their weights and heights were measured. The subjects were interviewed during regular class time. Hemoglobin concentration and dietary and activity patterns were assessed among a subsample (n = 787) of 1,521 adolescents. The World Health Organization age- and sex-specific references for body-mass index and height-for-age were used to estimate the prevalence of underweight and stunting, respectively. The International Obesity Task Force age- and sex-specific reference for body-mass index was used to estimate the prevalence of overweight. Age-specific WHO-defined cut off points were used to estimate the prevalence of anemia. RESULTS: The prevalence rates of underweight, stunting, and overweight were 47.2%, 28.5%, and 2.2%, respectively. The prevalence rates of anemia and vitamin A deficiency were 11.1% and 0.4%, respectively. During the previous 6 months, 10.4% of the subjects had usually not eaten breakfast before going to school. During the week before the interview, 24.4% of the children had not consumed green leafy vegetables, 26.6% had not consumed fruit, 19.0% had not participated in physical activities, and 27.5% had watched television for more than 2 hours per day. CONCLUSIONS: The nutritional problems of adolescents aged 10 to 15 years should be addressed through the schools. Specific policies should be developed in collaboration with the Ministry of Health and Education to control nutritional problems among adolescents.     

Groundwater quality in some villages of Haryana, India: focus on fluoride and fluorosis

The fluoride concentration in underground water was determined in four villages of Jind district of Haryana state (India) where it is the only source of drinking water. Various other water quality parameters such as pH, electrical conductivity, total dissolved salts, total hardness, total alkalinity as well as sodium, potassium, calcium, magnesium, carbonate, bicarbonate, chloride and sulfate concentrations were also measured. A systematic calculation of correlation coefficients among different physico-chemical parameters was performed. The analytical results indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO standards for most of the water quality parameters measured. The fluoride concentration in the underground water of these villages varied from 0.3 to 6.9 mg/l, causing dental fluorosis among people especially children of these villages. Overall water quality was found unsatisfactory for drinking purposes without any prior treatment except at eight locations out of 60.     

Stearoyl-coenzyme A desaturase activity in novikoff hepatoma

The activities of microsomal stearoyl-CoA desaturation, NADH-cytochrome b₅ reductase, NADH-cytochrome c reductase, and the content of cytochrome b₅ were similar in livers of normal and host rats. On the other hand, stearoyl-CoA desaturation activity was absent in Novikoff hepatoma. The activities of NADH-cytochrome b₅ and NADH-cytochrome c reductases in the hepatoma microsomes were 4.8% and 2.2%, respectively, of those in normal liver. Furthermore, in hepatoma microsomes, cytochrome b₅ was absent. An active stearoyl-CoA desaturation was reconstituted only on addition of both cytochrome b₅ and the terminal desaturase enzyme to the hepatoma microsomes. These results indicated that a complete absence of cytochrome b₅ and terminal desaturase is responsible for the lack of stearoyl-CoA desaturation in Novikoff hepatoma microsomes.     

九区控制(诊断法电解控制)在神火铝电200kA电解槽上的应用

电流效率和电能消耗是铝电解生产中最重要的指标。因此．对全世界的铝厂来说提高电流效率的同时降低电耗成为一个挑战性课题。一项全新的热量和物质平衡控制模型(称之为9区控制模型)，首次在河南神火铝电公司200kA电解槽上进行试验。通过六个多月的试验，9区控制有效地稳定了电解生产过程，降低了温度波动，使电流效率提高了1．04％．直流电耗降低了174kWh／t-Al。