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Nanoemulsions loaded with Ascorbyl Palmitate were prepared and incorporated into Carbopol® Ultrez hydrogels. The nanoemulsions presented diameter (200 nm ± 4.02), polydispersion index (0.186 ± 0.021, zeta potential (−12 mV ± 2.14), pH (3.61 ± 0.02), spherical morphology and active content (1 mg/mL). Cytotoxicity tests showed that the decrease in cell viability (VERO cells and 293T Fibroblasts) was dose-dependent. The hydrogels showed satisfactory organoleptic characteristics, diameter (226 nm ± 8.21), polydispersity index (0 0.2 ± 0.01), pH (3.5 ± 0.26), spreadability (3.96 ± 0.13 mm2.g−1) and viscosity (9253 ± 2130 mPa.s). Antioxidant activity tests showed that the hydrogels kept under refrigeration had their antioxidant activity preserved for 30 days (10 μMol TE/μL (DPPH) and 10.4 μMol TE/μL (ABTS)), while the nanoemulsions showed a reduction (values lower than 5 μMol TE μL) after 30 days. The hydrogels maintained the antioxidant activity of Ascorbyl Palmitate.

Context Tall fescue (Festuca arundinacea Schreb.) is a valuable temperate forage grass. Tall fescue plants associated with Epichloë fungal endophytes are successfully spreading in grassland regions that are recurrently exposed to flooding. Aims We asked whether the association with fungal endophytes increases plant performance under water excess. Methods In a greenhouse experiment, we evaluated the differential performance of young endophyte-infected and endophyte-free tall fescue plants in response to 14days of partial and total submergence. We included a wild local population and a cultivar, each with their respective fungal endophyte: the common endophyte and a safe (non-toxic) endophyte (AR584). Key results Relative to control (non-submerged) plants, and regardless of endophyte status, total submergence resulted in a significant growth reduction. At the end of the partial submergence period, the number of leaves per plant increased (21%) in the presence of the safe endophyte AR584 but decreased (18%) in the presence of the wild endophyte. Moreover, under partial submergence, the presence of wild endophyte decreased pseudostem dry weight by 10%. Conclusions Our results show that the presence of either the wild or the safe endophyte did not increase the performance of young tall fescue plants under submergence conditions. Implications Although all endophyte-free and endophyte-infected tall fescue plants survived submergence treatments, we cannot rule out that Epichloë endophytes might improve plant fitness under longer stressful submergence conditions. Future research should explore how endophytes modulate host performance under water excess, considering different phenological plant phases and/or co-occurrence with other stress factors (e.g. high temperatures).

A quantitative doping density mapping technique for silicon samples with micrometer spatial resolution is presented. Being based on confocal microphotoluminescence spectroscopy, the technique allows for detailed quantitative analyses on the doping concentration of microscopic technological structures in silicon solar cells. The confocal microscope setup enables laser illumination with micrometer-sized focus and fast low-noise detection of the emitted luminescent radiation which depends on doping and free excess carrier density. The doping density is determined by calibrating the depth-dependent luminescent radiation with results from 2-D simulations of the carrier density. The high-resolution method is demonstrated on a state-of-the-art doping structure for back contact solar cells, where small deviations in the doping homogeneity can be detected. This proves the potential of the proposed technique to enhance the processing of doping microstructures and to strengthen the understanding of their physical properties.

Forecasts of species range shifts as a result of climate change are essential, because invasions by exotic species shape biodiversity and therefore ecosystem functions and services. Ecologists have focused on propagule pressure (for example, the number of individuals and invasion events), the characteristics of an invading species, and its new abiotic and biotic environment to predict the likelihood of range expansion and invasion. Here, we emphasize the role of photoperiodic response on the range expansion of species. Unlike temperature, the latitudinal gradient of seasonal changes in day length is a stable, abiotic environmental factor that does not change with local or global climate. Predicting range expansions across latitudes and the subsequent consequences for native communities requires a more comprehensive understanding of how species use day length to coordinate seasonal growth, reproduction, physiology and synchronization of life cycles with interacting individuals and species.

Background Nevirapine single-dose (NVP-SD) reduces mother-to-child transmission of HIV type-1 (HIV-1), but frequently induces resistance mutations in the HIV-1 genome. Little is known about drug-resistant HIV-1 variants in the breast milk of women who have taken NVP-SD.Methods Blood and breast milk samples of 39 HIV-1-infected Ugandan women were taken 6–12 weeks after NVP-SD intake. Samples were analysed by population sequencing and allele-specific real-time PCR (AS-PCR) with detection limits for NVP-resistant HIV-1 variants (K103N and Y181C) of<1% of the total viral population.Results AS-PCR results for both plasma and breast milk were obtained for 19 women who constituted the final study group (HIV-1 subtype frequencies were A1 n=11, D n=5, G n=2 and C n=1). A total of 7 (37%) and 10 (53%) women carried NVP-resistant virus in breast milk and plasma, respectively. Overall, 71% (5/7) women with NVP-resistant HIV-1 in breast milk displayed>1 drug-resistant variant. Resistance in breast milk was higher at week 6 (6/13 samples [46%]) compared with week 12 (1/6 samples [17%]). In total, 10 drug-resistant populations harbouring the K103N and/or Y181C mutation were detected in the 19 breast milk samples; 7 (70%) were caused by resistant minorities (<5% of the total HIV-1 population). In the four women with drug-resistant virus in both plasma and breast milk, the mutation patterns differed between the two compartments.Conclusions Minor populations of drug-resistant HIV-1 were frequently found in breast milk of Ugandan women after exposure to NVP-SD. Further studies need to explore the role of minor drug-resistant variants in the postnatal transmission of (resistant) HIV-1.

The purpose of this pilot study was to determine the efficacy of ketorolac tromethamine 0.4% for pain management in conjunction with rigid gas permeable contact lenses in keratoconus. Any potential side effects and complications of this application were examined.

Internal stress is strongly correlated with the mechanical stability of silicon wafers and with the distribution of defects and thus the minority carrier lifetime, which is often the limiting parameter for multicrystalline mc silicon solar cells. Therefore, internal stress is a highly relevant parameter for mc silicon. In this paper, a qualitative internal stress measurement technique by photoluminescence spectroscopy for mc silicon is presented. This technique is based on the stressinducedbandgap energy shift. Stress measurements are compared to defect luminescence images, which are gathered in the same measurement. The method is evaluated by stress measurements with microRaman spectroscopy.

A modular set of oligosaccharide building blocks was developed for the synthesis of multiantennary N‐glycans of the complex type, which are commonly found on glycoproteins. The donor building blocks were laid out for the elongation of a core trisaccharide acceptor (β‐mannosyl chitobiose) conveniently protected with a single benzylidene moiety at the β‐mannoside. Through two consecutive regio‐ and stereoselective couplings the donors gave N‐glycans with three to five antennae in high yields. Due to the consistent protection group pattern of the donors the deprotection of the final products can be performed by using a general reaction sequence.

ABSTRACTNevirapine (single dose), commonly used to prevent the mother-to-child transmission of human immunodeficiency virus (HIV) in developing countries, frequently induces viral resistance. Even mutations which occur only in a minor population of the HIV quasispecies (<20%) are associated with subsequent treatment failure but cannot be detected by population-based sequencing. We developed sensitive allele-specific real-time PCR (ASPCR) assays for two key resistance mutations of nevirapine. The assays were specifically designed to analyze HIV-1 subtype A and D isolates accounting for the majority of HIV infections in Uganda. Assays were evaluated using DNA standards and clinical samples of Ugandan women having preventively taken single-dose nevirapine. Lower detection limits of drug-resistant HIV type 1 (HIV-1) variants carrying reverse transcriptase mutations were 0.019% (K103N [AAC]), 0.013% (K103N [AAT]), and 0.29% (Y181C [TGT]), respectively. Accuracy and precision were high, with coefficients of variation (the standard ratio divided by the mean) of 0.02 to 0.15 for intra-assay variability and those of 0.07 to 0.15 (K103N) and 0.28 to 0.52 (Y181C) for inter-assay variability. ASPCR assays enabled the additional identification of 12 (20%) minor drug-resistant HIV variants in the 20 clinical Ugandan samples (3 mutation analyses per patient; 60 analyses in total) which were not detectable by population-based sequencing. The individual patient cutoff derived from the clinical baseline sample was more appropriate than the standard-based cutoff from cloned DNA. The latter is a suitable alternative since the presence/absence of drug-resistant HIV-1 strains was concordantly identified in 92% (55/60) of the analyses. These assays are useful to monitor the emergence and persistence of drug-resistant HIV-1 variants in subjects infected with HIV-1 subtypes A and D.

AbstractIn this study, a correction was developed for the aethalometer to measure real-time black carbon (BC) concentrations in an environment dominated by fresh diesel soot. The relationship between the actual mass-specific absorption coefficient for BC and the BC-dependent attenuation coefficients was determined from experiments conducted in a diesel exposure chamber that provided constant concentrations of fine particulate matter (PM; PM2.5; PM <2.5 µm in aerodynamic diameter) from diesel exhaust. The aethalometer reported BC concentrations decreasing with time from 48.1 to 31.5 µg m−3when exposed to constant PM2.5concentrations of 55 ± 1 µg m−3and bscat= 95 ± 3 Mm−1from diesel exhaust. This apparent decrease in reported light-absorbing PM concentration was used to derive a correction K(ATN) for loading of strong light-absorbing particles onto or into the aethalometer filter tape, which was a function of attenuation of light at 880 nm by the embedded particles.

BACKGROUND AND STUDY AIMS: In the past, there were long delays in the diagnosis of patients with cancer of the stomach or esophagus. The objective of this study was to describe current delays in the diagnosis and treatment of gastric and esophageal adenocarcinoma and to compare the findings with those from an historical control population treated at the same institutions 10 years earlier. PATIENTS AND METHODS: Patients with biopsy-proven gastric cancer or esophageal adenocarcinoma who were treated at two academic medical centers in Germany between April and October 2003 were consecutively screened for eligibility to take part in the study. Medical charts for each patient were reviewed. Additional data were obtained via structured interviews. Main outcome measures were the total delay, and the delays related to patients themselves, to doctors, and to the hospital. Data were compared with those from a historic control group assessed in 1993. RESULTS: The median total delay for patients with gastric cancer (n = 104) was 3.5 months (range 0.3 - 29.6), and in patients with esophageal adenocarcinoma (n = 22) the total delay was significantly shorter (median 2.2 months, range 1.2 - 11.7; P < 0.05). Comparing these findings with those from an historic cohort of patients with gastric cancer (n = 100) revealed a significant decrease in the total delay (3.5 versus 8.0 months, P < 0.001). CONCLUSIONS: The current findings indicate that delays in the diagnosis and treatment of gastric cancer have become significantly shorter within the last 10 years as our understanding of and ability to treat this form of cancer have improved.

In this study we evaluated alternative CD4+ T‐cell counting methods in clients of a PMTCT Programme in rural Uganda.The Coulter Manual CD4 Count method for CD4+ T‐cell enumeration (Cyto‐Spheres) and an automated method (volumetric, single‐platform flow cytometry; CyFlow) were compared with a standard, dual‐platform flow cytometry protocol (DPFC, FACScan).Correlation and precision of agreement were higher for the CyFlow method (r = 0.929 and η = 0.08) when compared to DPFC than for the Cyto‐Spheres method (r = 0.725 and η = 0.3). Multiple linear regression analysis showed that CD4+ cell counts by the CyFlow method were a stronger predictor for results of DPFC than those of the Cyto‐Spheres method (r2 = 0.864 and r2 = 0.552, respectively). When compared to DPFC the CyFlow method generated higher CD4+ cell counts than the Cyto‐Spheres method, as expressed by a higher median and mean difference (+70 and +90 cells for CyFlow, +28 and −1.4 cells for Cyto‐Spheres).Both, the manual Cyto‐Spheres method and the CyFlow method can be used for the enumeration of CD4+ cells in resource‐limited settings. Under supervised conditions, the CyFlow method produced results more consistent with the reference method than the Cyto‐Spheres method. © 2006 International Society for Analytical Cytology

Tree establishment can have multiple effects on the production and biodiversity of rangelands. In mixed (C3–C4) grasslands, winter deciduous trees could favor cold-season species in the understory, improving forage availability in the most critical time of the year. Yet, they could also promote local extinctions and invasions, risking native biodiversity. We evaluate the effect of poplar planting on the structure, composition, and diversity of native grasslands in the Flooding Pampas of Argentina using a network of 9 pairs of adjacent nonafforested and afforested stands (age: 23–25 years, density: 625–1 111 plants ha−1) located in different topographic positions. Phytosociological surveys, basal cover measurements, and tree volume were performed at all stands. Live plant cover was 42% lower under poplars (P< 0.05). Litter cover followed an opposite trend leaving bare soil proportions unchanged with afforestation. Afforested stands had a higher proportion of C3 species compared with nonafforested ones. Little evidence of local extinctions or invasions with afforestation was found. Poplar understories had significantly higher nonnative species cover but similar numbers and lower species diversity (Shannon–Weaver index) yet similar species richness when compared with their nonafforested counterparts. Beyond the diversification of ranch outputs, deciduous tree plantations in the Flooding Pampas can offer a good forage source in their understory that complements nonafforested natural grasslands in quality and seasonality.

Awareness and knowledge about HIV mother-to-child transmission (MTCT) and preventive measures in different population groups and health personnel were analysed in future intervention areas in western Uganda and south-western Tanzania. In Uganda, a total of 751 persons (440 clients of antenatal and outpatient clinics, 43 health workers, 239 villagers, 29 traditional birth attendants) and in Tanzania, 574 persons (410 clients, 49 health workers, 93 villagers, 18 traditional birth attendants) were interviewed. When given options, knowledge on transmission during pregnancy and delivery in women was 93% and 67% in Uganda and Tanzania respectively, and 86% and 78% for transmission during breastfeeding. In Uganda 59% of male interviewees did not believe that HIV is transmitted during breastfeeding. Expressed acceptance of HIV testing was above 90% in men and women in both countries, but only 10% of the clients in Uganda and 14% in Tanzania had been tested for HIV infection. Health workers' knowledge regarding MTCT was acceptable, while traditional birth attendants' knowledge on both MTCT and preventive measures was extremely poor. Recommendations on infant feeding were not compatible with WHO recommendations for HIV-infected women. If prevention of MTCT (PMTCT) interventions are to be accepted by the population and promoted by health personnel, thorough orientation and training are mandatory.

An ICP-MS equipped with collision cell, sector field and multi-collector technology has been applied to developing analytical procedures for Fe in terms of isotope ratio measurements and isotope dilution analysis. Therefore a detailed study on the reduction of molecular interferences by a variety of collision gases He, Ar, Kr, H2, D2and N2 was performed. The efficiency of the reduction has been checked by high resolution mass scans. The argon based interferences disturbing the determination of 54Fe and 56Fe could be completely removed when using Faraday detectors. The interferences on mass 57 could be reduced to a level which enables accurate measurements. Also, the 40Ar12C interference, which disturbs the chromium correction, could be completely removed. Reproducibilities of 0.01 could be reached for 54Fe56Fe isotope ratios and 0.02 for 57Fe56Fe isotope ratios. Under these measurement conditions a sensitivity of 1.2 V per 50 µg kg−1Fe is available. This corresponds to 1.5 × 109cps per mg kg−1. Based on these results highly accurate procedures for Fe isotope ratio determinations were set up, reaching a performance level superior to that of other ICP-MS instruments. Consequently, IDMS procedures were developed on this basis in order to perform certification measurements at the highest metrological level. The first application was the contribution to the Fe reference value by IMEP-12, an interlaboratory comparison with approximately 350 participants worldwide. The analysed Fe mass content is 0.2150 mg kg−1with its expanded uncertainty k 2 of 0.0012 mg kg−10.56, which is ten times less than the uncertainty of the second certification laboratory. Another application was the certification campaign of the two reference materials Tea Leaves and Polish Herbs. The results obtained with the ICP-MS procedure, 542 ± 11 mg kg−1and 543 ± 12 mg kg−1, were compared with the results analysed by TIMS, 541 ± 12 mg kg−1and 541 ± 13 mg kg−1, and agree very well within the stated uncertainties k 2. The results presented demonstrate quite well the suitability of the developed IDMS procedures for certification or reference measurements.

The animal tests currently carried out according to the German and European pharmacopoeias are evaluated. The routine testing of biological medicines, excluding vaccines and pyrogen tests, is examined. The opportunities for replacing obligatory bioassays and safety tests are assessed, taking into account both pharmaceutical quality and animal welfare aspects. The aim is to encourage institutions, public authorities, and the pharmaceutical industry to investigate the importance and the necessity of the remaining tests. In addition, all parties should be encouraged to initiate integrated projects to develop, validate and establish alternative methods.

Antiferroelectric lead zirconate titanate PZT (95/5) has been prepared by chemical solution deposition using alkoxide precursor compounds and was spin-coated on metallic substrates of Hastelloy. In order to better adapt the substrate to the PZT and thus to improve the crystallization behavior of the PZT films, different interface layers have been studied. The annealing parameters have been optimized in the case of an intermediate RuO 2 layer. Other interface layers like indium tin oxide (ITO) or lanthanum strontium manganate (LSMO) can be compared to deposition of the PZT on Hastelloy and on platinum coated Hastelloy. Using conventional multi-coating technique, homogeneous antiferroelectric films of up to 2.5 w m thickness have been obtained.

In order to improve the experimental conditions for electron emission from ferroelectric thin films, the dynamic behavior of polarization inversion has been studied by the conventional pulse switching method. Thus, it could be demonstrated that ferroelectric switching mainly depends on the experimental geometry and the pulse circuit impedance. Results are presented which introduce the difference between the nominal electric field and the electric field which governs the switching process. In particular, it has be shown that polarization inversion not only starts at the coercive field amplitude but is almost completed at the same field. As a consequence, it is not necessary to increase the field amplitude in order to reduce the switching time.