Cusp observation at Saturn's high-latitude magnetosphere by the Cassini spacecraft.

We report on the first analysis of magnetospheric cusp observations at Saturn by multiple in situ instruments onboard the Cassini spacecraft. Using this we infer the process of reconnection was occurring at Saturn's magnetopause. This agrees with remote observations that showed the associated auroral signatures of reconnection. Cassini crossed the northern cusp around noon local time along a poleward trajectory. The spacecraft observed ion energy-latitude dispersions-a characteristic signature of the terrestrial cusp. This ion dispersion is "stepped," which shows that the reconnection is pulsed. The ion energy-pitch angle dispersions suggest that the field-aligned distance from the cusp to the reconnection site varies between ∼27 and 51 RS . An intensification of lower frequencies of the Saturn kilometric radiation emissions suggests the prior arrival of a solar wind shock front, compressing the magnetosphere and providing more favorable conditions for magnetopause reconnection. KEY POINTS: We observe evidence for reconnection in the cusp plasma at SaturnWe present evidence that the reconnection process can be pulsed at SaturnSaturn's cusp shows similar characteristics to the terrestrial cusp.

Disclosure behaviour and experienced reactions in patients with HIV versus chronic viral hepatitis or diabetes mellitus in Germany.

Disclosure is a prerequisite to receive disease-specific social support. However, in the case of a stigmatised disease, it can also lead to discrimination. We aimed to assess disclosure rates of HIV patients and the reactions they encountered in comparison to patients with chronic viral hepatitis or diabetes mellitus and patients' general perception of disease-specific discrimination. We constructed a self-report questionnaire, anonymously assessing the size of the social environment, the persons who had been informed, and the experienced reactions as perceived by the disclosing patients, to be rated on 1-4 point Likert scales. In addition, patients were asked whether they perceive general discrimination in Germany. One hundred and seventy-one patients were asked to participate. Five rejected, thus questionnaires from 83 patients with HIV, 42 patients with chronic viral hepatitis B (n = 9) or C (n = 33), and 41 patients with insulin-dependent diabetes mellitus (type I n = 14, type II n = 27) were analysed. Whereas the size of the social environment did not differ, HIV-infected patients were least likely to disclose their disease (60.7%, SD ± 31.9) to their social environment as compared to patients with chronic viral hepatitis (84.2 ± 23.3%, p<0.0001), or diabetes mellitus (94.4 ± 10.3%, p<0.0001), respectively. Within the HIV patient group, the mean disclosure rate was highest to partners (90.9%), followed by the public environment (65.2%), friends (59.4%) and family members (43.8%). HIV patients experienced supportive reactions after 79.3 ± 26.4% of disclosures, which was the case in 91.4 ± 19.6% and 75.7 ± 36.1% of patients with hepatitis or diabetes mellitus, respectively. 69.5% of HIV patients stated to perceive general discrimination in Germany. We conclude that HIV patients had experienced supportive reactions after the majority of disclosures, but the low rate points out that their information strategy had been very selective. Societal discrimination of HIV patients is still an issue and needs to be further addressed.

Interlayer excitons in MoSe2/2D perovskite hybrid heterostructures - the interplay between charge and energy transfer.

van der Waals crystals have opened a new and exciting chapter in heterostructure research, removing the lattice matching constraint characteristics of epitaxial semiconductors. They provide unprecedented flexibility for heterostructure design. Combining two-dimensional (2D) perovskites with other 2D materials, in particular transition metal dichalcogenides (TMDs), has recently emerged as an intriguing way to design hybrid opto-electronic devices. However, the excitation transfer mechanism between the layers (charge or energy transfer) remains to be elucidated. Here, we investigate PEA2PbI4/MoSe2 and (BA)2PbI4/MoSe2 heterostructures by combining optical spectroscopy and density functional theory (DFT) calculations. We show that band alignment facilitates charge transfer. Namely, holes are transferred from TMDs to 2D perovskites, while the electron transfer is blocked, resulting in the formation of interlayer excitons. Moreover, we show that the energy transfer mechanism can be turned on by an appropriate alignment of the excitonic states, providing a rule of thumb for the deterministic control of the excitation transfer mechanism in TMD/2D-perovskite heterostructures.

Supposedly identical microplastic particles substantially differ in their material properties influencing particle-cell interactions and cellular responses.

Microplastics and its putative adverse effects on environmental and human health increasingly gain scientific and public attention. Systematic studies on the effects of microplastics are currently hampered by using rather poorly characterised particles, leading to contradictory results for the same particle type. Here, surface properties and chemical composition of two commercially available nominally identical polystyrene microparticles, frequently used in effect studies, were characterised. We show distinct differences in monomer content, ζ-potentials and surface charge densities. Cells exposed to particles showing a lower ζ-potential and a higher monomer content displayed a higher number of particle-cell-interactions and consequently a decrease in cell metabolism and proliferation, especially at higher particle concentrations. Our study emphasises that no general statements can be made about the effects of microplastics, not even for the same polymer type in the same size class, unless the physicochemical properties are well characterised.

The HLA-B 3906 allele imparts a high risk of diabetes only on specific HLA-DR/DQ haplotypes.

AIMS/HYPOTHESIS: We investigated the risk associated with HLA-B*39 alleles in the context of specific HLA-DR/DQ haplotypes. METHODS: We studied a readily available dataset from the Type 1 Diabetes Genetics Consortium that consists of 2,300 affected sibling pair families genotyped for both HLA alleles and 2,837 single nucleotide polymorphisms across the major histocompatibility complex region. RESULTS: The B*3906 allele significantly enhanced the risk of type 1 diabetes when present on specific HLA-DR/DQ haplotypes (DRB1 0801-DQB1 0402: p = 1.6 × 10(-6), OR 25.4; DRB1 0101-DQB1 0501: p = 4.9 × 10(-5), OR 10.3) but did not enhance the risk of DRB1 0401-DQB1 0302 haplotypes. In addition, the B 3901 allele enhanced risk on the DRB1 1601-DQB1 0502 haplotype (p = 3.7 × 10(-3), OR 7.2). CONCLUSIONS/INTERPRETATION: These associations indicate that the B 39 alleles significantly increase risk when present on specific HLA-DR/DQ haplotypes, and HLA-B typing in concert with specific HLA-DR/DQ genotypes should facilitate genetic prediction of type 1 diabetes, particularly in a research setting.

1,2-Diphenyl-1H-imidazo[4,5-f][1,10]phenanthroline.

In the title compound, C(25)H(16)N(4), the fused ring system is essentially planar [maximum deviation = 0.1012 (15) Å]. The imidazole ring makes dihedral angles of 77.41 (8) and 56.26 (8)° with the phenyl rings attached to nitro-gen and carbon, respectively. The dihedral angle between the two phenyl rings is 65.50 (8)°. Weak C-H⋯π inter-actions are found in the crystal structure.

1-(3,5-Dimethyl-phenyl)-2-(4-fluoro-phenyl)-4,5-dimethyl-1H-imidazole.

In the title compound, C(19)H(19)FN(2), the imidazole ring is essentially planar [maximum deviation of 0.0015 (9) Å] and makes dihedral angles of 77.61 (9) and 26.93 (10)° with the benzene rings attached to nitro-gen and carbon, respectively. The dihedral angle between the two benzene rings is 78.84 (8)°. A C-H⋯π inter-action is found in the crystal structure.

2-(4-Fluoro-phen-yl)-1-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline monohydrate.

In the title compound, C(25)H(15)FN(4)·H(2)O, the fused ring system is essentially planar [maximum deviation of 0.0822 (14) Å]. The imidazole ring makes dihedral angles of 76.83 (7) and 32.22 (7)° with the phenyl group attached to nitro-gen and the fluoro-benzene group to carbon, respectively. The dihedral angle between the two phenyl rings is 72.13 (7)°. Inter-molecular O-H⋯N, O-H⋯F, C-H⋯F, C-H⋯O and C-H⋯N hydrogen bonds are found in the crystal structure.

2-(2-Chloro-phen-yl)-3-methyl-5,6-diphenyl-2,3-dihydro-pyrazine.

In the title mol-ecule, C(23)H(19)ClN(2), the heterocyclic ring adopts a screw-boat conformation, with all substituents equatorial. The benzene ring at position 2 makes dihedral angles of 77.88 (12) and 76.31 (12)° with the phenyl rings at positions 5 and 6, respectively. The dihedral angle between the phenyl rings at positions 5 and 6 is 70.05 (10)°. The Cl atom is disordered over two positions with occupancy factors of 0.946 (5) and 0.054 (5). In the crystal, C-H⋯π inter-actions are found.

rs2476601 T allele (R620W) defines high-risk PTPN22 type I diabetes-associated haplotypes with preliminary evidence for an additional protective haplotype.

Protein tyrosine phosphatase non-receptor type 22 (PTPN22) is the third major locus affecting risk of type I diabetes (T1D), after HLA-DR/DQ and INS. The most associated single-nucleotide polymorphism (SNP), rs2476601, has a C->T variant and results in an arginine (R) to tryptophan (W) amino acid change at position 620. To assess whether this, or other specific variants, are responsible for T1D risk, the Type I Diabetes Genetics Consortium analyzed 28 PTPN22 SNPs in 2295 affected sib-pair (ASP) families. Transmission Disequilibrium Test analyses of haplotypes revealed that all three haplotypes with a T allele at rs2476601 were overtransmitted to affected children, and two of these three haplotypes showed statistically significant overtransmission (P=0.003 to P=5.9E-12). Another haplotype had decreased transmission to affected children (P=3.5E-05). All haplotypes containing the rs2476601 T allele were identical for all SNPs across PTPN22 and only varied at centromeric SNPs. When considering rs2476601 'C' founder chromosomes, a second haplotype (AGGGGC) centromeric of PTPN22 in the C1orf178 region was associated with protection from T1D (odds ratio=0.81, P=0.0005). This novel finding requires replication in independent populations. We conclude the major association of PTPN22 with T1D is likely due to the recognized non-synonymous SNP rs2476601 (R620W).

The frequent and conserved DR3-B8-A1 extended haplotype confers less diabetes risk than other DR3 haplotypes.

AIM: The goal of this study was to develop and implement methodology that would aid in the analysis of extended high-density single nucleotide polymorphism (SNP) major histocompatibility complex (MHC) haplotypes combined with human leucocyte antigen (HLA) alleles in relation to type 1 diabetes risk. METHODS: High-density SNP genotype data (2918 SNPs) across the MHC from the Type 1 Diabetes Genetics Consortium (1240 families), in addition to HLA data, were processed into haplotypes using PedCheck and Merlin, and extended DR3 haplotypes were analysed. RESULTS: With this large dense set of SNPs, the conservation of DR3-B8-A1 (8.1) haplotypes spanned the MHC (>/=99% SNP identity). Forty-seven individuals homozygous for the 8.1 haplotype also shared the same homozygous genotype at four 'sentinel' SNPs (rs2157678 'T', rs3130380 'A', rs3094628 'C' and rs3130352 'T'). Conservation extended from HLA-DQB1 to the telomeric end of the SNP panels (3.4 Mb total). In addition, we found that the 8.1 haplotype is associated with lower risk than other DR3 haplotypes by both haplotypic and genotypic analyses [haplotype: p = 0.009, odds ratio (OR) = 0.65; genotype: p = 6.3 x 10(-5), OR = 0.27]. The 8.1 haplotype (from genotypic analyses) is associated with lower risk than the high-risk DR3-B18-A30 haplotype (p = 0.01, OR = 0.23), but the DR3-B18-A30 haplotype did not differ from other non-8.1 DR3 haplotypes relative to diabetes association. CONCLUSION: The 8.1 haplotype demonstrates extreme conservation (>3.4 Mb) and is associated with significantly lower risk for type 1 diabetes than other DR3 haplotypes.

Applying imidacloprid via a precision banding system to control striped cucumber beetle (Coleoptera: Chrysomelidae) in cucurbits.

The striped cucumber beetle, Acalymma vittatum (F.) (Coleoptera: Chrysomelidae), is a key pest of cucurbit crops throughout its range. A novel precision band applicator was designed to inject a solid stream of imidacloprid solution in-furrow directly over the seed during planting to reduce beetle leaf feeding on pumpkin, zucchini, and cucumber crops. In 2004 and 2005, bioassays at the cotyledon through fifth leaf were conducted on striped cucumber beetles using seedling leaf tissue grown from seeds treated using both continuous and precision banded in-furrow imidacloprid solution applications. In 2004, 80% of bioassay trials had treatments with beetle mortality significantly higher than the check, whereas 70% of the bioassay trials showed no significant difference in mortality between continuous in-furrow and precision banded treatments. In 2005, 79% of bioassay trials had treatments with beetle mortality significantly higher than the check, whereas 100% of the bioassays showed no significant difference in beetle mortality between continuous in-furrow and precision banded treatments at the same insecticide rate. The environmental savings of precision banded treatments compared with continuous in-furrow treatment reduced imidacloprid up to 84.5% on a per hectare basis for all cucurbits tested in 2004 and 2005, translating into an economic savings up to $215/ha. In separate bioassay trials conducted in 2005 on pumpkin, where insecticide band length and injection volume were manipulated independently, several treatments had significantly higher beetle mortality than the check. There was a trend of increased beetle mortality in treatments using shorter band lengths combined with higher insecticide solution volumes.

Influence of Ar-ion implantation on the structural and mechanical properties of zirconia as studied by Raman spectroscopy and nanoindentation techniques.

In this study, structural and nanomechanical properties of zirconia polymorphs induced by ion irradiation were investigated by means of Raman spectroscopy and nanoindentation techniques. The zirconia layer have been produced by high temperature oxidation of pure zirconium at 600 °C for 5 h at normal atmospheric pressure. In order to distinguish between the internal and external parts of zirconia, the spherical metallographic sections have been prepared. The samples were irradiated at room temperature with 150 keV Ar+ ions at fluences ranging from 1 × 1015 to 1 × 1017 ions/cm2. The main objective of this study was to distinguish and confirm different structural and mechanical properties between the interface layer and fully developed scale in the internal/external part of the oxide. Conducted studies suggest that increasing ion fluence impacts Raman bands positions (especially characteristic for tetragonal phase) and increases the nanohardness and Young's modulus of individual phases. This phenomenon has been examined from the point of view of stress-induced hardening effect and classical monoclinic → tetragonal (m → t) martensitic phase transformation.

Direct Band Gap Gallium Antimony Phosphide (GaSbxP(1-x)) Alloys.

Here, we report direct band gap transition for Gallium Phosphide (GaP) when alloyed with just 1-2 at% antimony (Sb) utilizing both density functional theory based computations and experiments. First principles density functional theory calculations of GaSbxP(1-x) alloys in a 216 atom supercell configuration indicate that an indirect to direct band gap transition occurs at x = 0.0092 or higher Sb incorporation into GaSbxP(1-x). Furthermore, these calculations indicate band edge straddling of the hydrogen evolution and oxygen evolution reactions for compositions ranging from x = 0.0092 Sb up to at least x = 0.065 Sb making it a candidate for use in a Schottky type photoelectrochemical water splitting device. GaSbxP(1-x) nanowires were synthesized by reactive transport utilizing a microwave plasma discharge with average compositions ranging from x = 0.06 to x = 0.12 Sb and direct band gaps between 2.21 eV and 1.33 eV. Photoelectrochemical experiments show that the material is photoactive with p-type conductivity. This study brings attention to a relatively uninvestigated, tunable band gap semiconductor system with tremendous potential in many fields.

Tandem chain extension-aldol reaction: syn selectivity with a zinc enolate.

A tandem chain extension-aldol reaction was developed in which beta-keto esters are transformed to alpha-substituted-gamma-keto esters in an efficient zinc-mediated, one-pot reaction. The diastereoselectivity of the reaction ranged from good to excellent with syn stereochemistry observed for beta-keto ester and amide substrates and anti-stereochemistry observed for a beta-keto imide. [reaction: see text]

Childhood physical and sexual abuse as risk factors for heavy drinking among African-American women: a prospective study.

OBJECTIVE: This study examines the associations among characteristics of child sexual abuse. childhood physical abuse, lack of parental care, and heavy drinking in a relatively young, urban population of African-American women all of whom have documented histories of child sexual abuse. METHODOLOGY: The sample consists of 113 African American child victims who were brought to a city hospital emergency room for treatment and collection of forensic evidence in the 1970s and re-interviewed as adults in the 1990s. RESULTS: The results of this research suggest that multiple incidents of child sexual abuse, more than the characteristics of such abuse is an important predictor of adult heavy alcohol use and binge drinking. These results remain even after controlling for the effects of parental drinking behavior. CONCLUSION: Although the victim of multiple child sexual assaults is more likely to suffer force and penetration, these analyses suggest that it is the multiple victimization and not the force or penetration that drives the relationship between child sexual assault and drinking behaviors.

The circumboreal tundra-taiga interface: late Pleistocene and Holocene changes.

Creating a global perspective on past treeline changes is problematic due to the varying methods and definitions used. A general lack of a detailed description of the modern treeline position and vegetation complicates any comparative analysis of the magnitude of the most important changes. However, one seemingly common factor in most regions was an extremely rapid dispersal of trees when climate warmed drastically from full glacial conditions. Most Arctic treelines reached their northernmost positions in the early Holocene and receded to present positions starting at about 5.8 ka. The early occupation of the northernmost sites in ice-free and early deglaciated areas was possible because of the close proximity of invading trees in nearby glacial refugia, particularly in Fennoscandia and northern Russia. In Canada, the Northwest Territories and Quebec-Labrador were out of phase with this general trend due to their late deglaciation. However, even here colonization was rapid, indicating that the tree species were present adjacent to the glaciers. Following this trend and based on the present evidence, we propose a scenario of a continuous but modest occupation of eastern Beringia by spruce during the late-Pleistocene instead of an exceptionally rapid spread of conifers from the glacial refugium south of the Laurentide ice sheet (2000 to 3000 km in about 200 years), which typically has been assumed. Macrofossil evidence of scattered occurrences of "exotic species" (for instance Siberian larch in central Sweden) far from their natural range limits in the early Holocene highlight the disparity between pollen and macrofossil analyses. It questions the validity of assigned pollen percentages to indicate the presence of a species within a region as these species were not observed in the pollen record. Thus, it is likely that trees were present at any given site well before the rise in pollen abundance. There is still a large potential to improve our knowledge about the environmental history of the circumboreal treeline areas. In particular, future research should concentrate not only on patterns of species displacement, but on finding the factors, apart from climate, which cause treeline shifts.

Physical violence among Anglo, African American, and Hispanic couples: ethnic differences in persistence and cessation.

Research on violence against women has developed exponentially over the past 20 years, however, there are still many areas in which knowledge is scarce. In particular, there is very little empirical information regarding the cessation and persistence of intimate violence against women. There is even less research that looks at racial and ethnic differences in patterns of violence. This study uses data from the first and second waves of the National Survey of Families and Households to examine changing patterns of physical violence in a sample of approximately 3,000 married and cohabiting couples. The results from the current study suggest that the same factors that might increase the initial risk for violent behavior may not affect whether or not this behavior continues. Additionally, the same risk factors may be related in different ways to different patterns of violence for different racial/ethnic groups.

Pregnancy, stress and wife assault: ethnic differences in prevalence, severity, and onset in a national sample.

Research using primarily hospital-based samples has suggested that pregnancy may put women at increased risk for wife assault, however, this research is largely limited by the lack of a comparison group of women who are not pregnant, and the failure to consider racial or ethnic differences in risk for violent victimization. The present study uses data from the 1992 National Alcohol and Family Violence Survey, a national probability sample of 1,970 individuals, to examine the prevalence, severity, and onset of wife assaults associated with pregnancy among Anglo and Hispanic families. The results indicated that pregnancy was associated with minor assaults among Hispanic women and severe assaults among Anglo women. Multivariate analyses revealed that among both Anglo and Hispanic families, there was no direct effect of pregnancy on risk for violent victimization after controlling for socioeconomic status, stressful life events, and age.

Sociocultural status and incidence of marital violence in Hispanic families.

It is not clear whether traditional cultural ideology influences wife assaults in Hispanic-American families, or if culture is confounded with the stresses of poverty, unemployment, and immigration status. Our 1992 study of 1,970 families, including a national oversample of Hispanic families, examines the incidence of marital violence in the three major Hispanic-American subgroups and in Anglo-American families, and considers how sociocultural status and attitudes towards violence affect wife assaults differentially. The findings show that Hispanic Americans, as a whole, do not differ significantly from Anglo Americans in their odds of wife assaults when norms regarding violence approval, age, and economic stressors are held constant. At the same time, considerable heterogeneity was apparent among ethnic subgroups on a number of measures. We also found that being born in the United States increases the risk of wife assaults by Mexican- and Puerto Rican- American husbands. However, the presence of norms sanctioning wife assaults within any group, regardless of socioeconomic status, is a risk factor for wife abuse.