Strain Relief Analysis of InN Quantum Dots Grown on GaN

We present a study by transmission electron microscopy (TEM) of the strain state of individual InN quantum dots (QDs) grown on GaN substrates. Moiré fringe and high resolution TEM analyses showed that the QDs are almost fully relaxed due to the generation of a 60° misfit dislocation network at the InN/GaN interface. By applying the Geometric Phase Algorithm to plan-view high-resolution micrographs, we show that this network consists of three essentially non-interacting sets of misfit dislocations lying along the directions. Close to the edge of the QD, the dislocations curve to meet the surface and form a network of threading dislocations surrounding the system.     

Influence of estrus of dairy goats on somatic cell count, milk traits, and sex steroid receptors in the mammary gland

Two experiments were conducted to study the effect of the stage of a spontaneous estrus cycle on milk yield and constituents [somatic cell count (SCC), fat, protein, caseins, lactose, and urea content] and on estrogen receptor-α (ERα) and progesterone receptor (PR) immunostaining in the mammary gland. In experiment I, the major components of milk and SCC were monitored weekly in 80 lactating Saanen goats for 6 wk, whereas detection of estrus was daily. In experiment II, milk samples were collected daily for SCC determination during 1 spontaneous estrus (d 0) until the second spontaneous estrus in 14 Saanen goats. The day of the estrous cycle was confirmed by plasma progesterone and 17β-estradiol levels. Immunoreactivity of ERα and PR was analyzed in mammary gland samples of 8 Saanen goats (d 0, n = 4; d 10, n = 4) and the number of positive nuclei and intensity of the staining were evaluated in 1,000 cells. In experiment I, milk casein and protein percentages were significantly affected by the stage of estrous cycle; during proestrus and estrus, these variables were higher (3.32 ± 0.06 and 4.44 ± 0.08) than during metestrus (3.03 ± 0.07 and 4.07 ± 0.10), but not higher than during diestrus (3.23 ± 0.06 and 4.35 ± 0.09, respectively). In experiment II, daily measurement of SCC revealed higher levels at estrus (7,195 ± 672 × 10³ cells/mL) and a decline toward the luteal phase (1,694 ± 672 ± 10³ cells/mL). Estrogen receptor-α and PR immunostaining were exclusively detected on epithelial cells. The percentage of positive nuclei to ERα was higher on d 0 than on d 10 (75.4 ± 8.8 vs. 68.3 ± 8.8%), but no change was observed for PR (4.0 ± 0.3 vs. 3.5 ± 0.4%). The average immunostaining intensity for both receptors was greater on d 0 than on d 10 (ERα : 1.44 ± 0.02 vs. 1.35 ± 0.02; PR: 0.079 ± 0.008 vs. 0.057 ± 0.008). The high SCC at estrus in experiment II was associated with high plasma estradiol and low progesterone, suggesting that the increased SCC could be brought about by the estrogen-induced proliferation and exfoliation of epithelial cells. In addition, this action may be supported by the higher sensitivity to estrogens (ERα content) found at d 0.     

Extensive feeding versus oleic acid and tocopherol enriched mixed diets for the production of Iberian dry-cured hams: Effect on chemical composition, oxidative status and sensory traits

The present study aimed to analyse the chemical composition and oxidative status of Iberian dry-cured hams from pigs fed different finishing diets: extensive feeding on acorns and pasture in a "Montanera" traditional system (MON), fed in confinement with a mixed diet containing high-oleic sunflower oil (115g/kg of diet) and supplemented with 250mg/kg α-tocopherol (HOVE), and fed in confinement control mixed diet (CON) without added tocopherol and oleic acid fat. Muscles from MON dry-cured hams contained significantly (p<0.05) higher amounts of intramuscular fat (IMF) than those from HOVE and CON hams. The feeding background affected the tocopherol levels in dry-cured hams as those from MON and HOVE pigs had significantly higher levels of α-tocopherol than those from CON pigs whereas the extensive feeding provided muscles from MON pigs with significantly higher levels of γ-tocopherol than the experimental diets did to CON and HOVE pigs. The HOVE diet significantly increased the levels of oleic acid in Iberian dry-cured hams with these levels being similar to the oleic acid levels found in MON hams and significantly higher than those in CON hams. Compared to dry-cured hams from CON pigs, those from MON and HOVE pigs exhibited a higher oxidative stability as a likely result of a most favourable fatty acid composition and the presence of higher tocopherol levels. The principal component analysis (PCA) successfully discriminated between dry-cured hams from pigs fed different finishing diets.     

Identification of meats from red deer (Cervus elaphus), fallow deer (Dama dama), and roe deer (Capreolus capreolus) using polymerase chain reaction targeting specific sequences from the mitochondrial 12S rRNA gene

Polymerase chain reaction (PCR) based on oligonucleotide primers targeting the mitochondrial 12S rRNA gene was applied to the specific identification of meats from red deer (Cervus elaphus), fallow deer (Dama dama), and roe deer (Capreolus capreolus). The use of a common reverse primer, together with forward specific primers for red deer, fallow deer, and roe deer, allowed the selective amplification of the desired cervid sequences. The specificity of each primer pair was verified by PCR analysis of DNA from various game and domestic meats. The assay can be useful for the accurate identification of meats from cervid species, avoiding mislabeling or fraudulent species substitution in meat products.     

The GPI-anchored Gas and Crh families are fungal antigens

The cell wall is the first interface between a fungus and its extracellular environment. Glycosyltransferases involved in the formation and dynamic remodelling of the polysaccharide network of the cell wall have recently been identified. The best characterized ones belong to the Gas family, which elongates beta(1,3)-glucans, and to the Crh family, which are involved in the cross-linking of chitin to beta(1,6)-glucan. All these proteins carry a glycosylphosphatidylinositol (GPI) anchor. In this work, we show that recombinant soluble forms of Gas1-5 and Crh1p from Saccharomyces cerevisiae and their orthologous proteins Gel1-Gel2 and Crf1 from Aspergillus fumigatus are specifically recognized by antibodies present in the sera of patients with Aspergillus or Candida infections. Quantification of the antibody titres against recombinant Gas/Gel and Crh/Crf proteins separated aspergilloma and candidiasis patients from non-infected individuals. Cross-reactivity was seen between the antibody response of patients with aspergillosis and candidiasis towards the Gas/Gel and Crh/Crf proteins. These results suggest that GPI-anchored cross-linking enzymes are relevant immunologically reactive constituents of the cell wall that may play a role during human fungal infections.     

Release of iron, zinc, and lead from common iron construction bars and zinc metallic bars in water solutions and meals

BACKGROUND: The use of iron pots has decreased the prevalence of anemia. OBJECTIVE: To investigate the release of iron, zinc, and lead from metallic iron and zinc bars incubated in water and in meals. METHODS: Iron, zinc, and lead concentrations were measured at different incubation conditions in water and in meals. RESULTS: The iron concentration in water was 1.26 mg/L after incubation with one iron bar at pH 7 and 100 degrees C for 20 minutes and in meals was 0.97 mg per 100 g of wet meals, rich in phytate, cooking at 100 degrees C during 20 minutes. The maximum contents were 7720 mg/L of iron and 1826 mg/L of zinc in vinegar at pH 3 and 20 degrees C after 90 and 32 days, respectively. Lead was released from the bars, but at concentrations well below the upper tolerable limits. DISCUSSION: In outreach populations, the use of iron and zinc metallic bars in water and meals could contribute to sustainable, very low-cost prevention of iron and zinc deficiencies, and home-fortified vinegar could be used for treatment of both deficiencies. CONCLUSIONS: Field trials should be performed to determine the impact that the use of iron and zinc metallic bars in water and meals might have on the iron and zinc status of population groups.     

水资源属性与水资源问题强相关分析

水资源是基础性自然资源,既有自然资源共有的特征,又有着区别于其他自然资源之特性,具有稀缺性、整体性、地域性、社会性、流动性、基础性、时限性、两重性等,表现为"复杂"的自然属性和"公共"的社会属性。现实中日趋严重的水资源问题(水资源短缺、污染、浪费,生态环境恶化)与水资源属性强相关,应运用复合系统观念和方法解决水资源问题。     

Pesticide determination by enzymatic inhibition and amperometric detection in a low-temperature cofired ceramics microsystem

Among the several fabrication techniques used to construct microflow systems, the low-temperature cofired ceramics (LTCC) technology, taking advantage of its multilayer approach, is one of the most versatile ones. It permits the integration of several unitary operations of an analytical process in a modular or monolithic way. Moreover, due to its perfect compatibility with screen-printing techniques, it also permits the integration of electronic components used to control the whole system setup. In this work the design, construction, and evaluation of a miniaturized analyzer for pesticide determination that integrates a pretreatment stage, based on two mixers or reactors, and an amperometric detection system to measure the product of an enzymatic inhibition reaction are presented. The detection system was monolithically integrated in the microfluidic platform, and it consisted of a screen-printed reference electrode and two platinum sheets, acting as auxiliary and working electrodes, which were embedded within the ceramic structure. The miniaturized system was characterized and successfully evaluated by determining carbofuran at the nanomolar level.     

Multiway partial least-squares coupled to residual trilinearization: a genuine multidimensional tool for the study of third-order data. Simultaneous analysis of procaine and its metabolite p-aminobenzoic acid in equine serum

A new third-order multivariate calibration approach, based on the combination of multiway-partial least-squares with a separate procedure called residual trilinearization (N-PLS/RTL), is presented and applied to multicomponent analysis using third-order data. The proposed chemometric algorithm is able to predict analyte concentrations in the presence of unexpected sample components, which require strict adherence to the second-order advantage. Results for the determination of procaine and its metabolite p-aminobenzoic acid in equine serum are discussed, based on kinetic fluorescence excitation-emission four-way measurements and application of the newly developed multiway methodology. Since the analytes are also the reagent and product of the hydrolysis reaction followed by fast-scanning fluorescence spectroscopy, the classical approach based on parallel factor analysis is challenged by strong linear dependencies and multilinearity losses. In comparison, N-PLS/RTL appears an appealing genuine multiway alternative that avoids the latter complications, yielding analytical results that are statistically comparable to those rendered by related unfolded algorithms, which are also able to process four-way data. Prediction was made on validation samples with a qualitative composition similar to the calibration set and also on test samples containing unexpected equine serum components.