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A large qubit capacity and an individual readout capability are two crucial requirements for large-scale quantum computing and simulation1. As one of the leading physical platforms for quantum information processing, the ion trap has achieved a quantum simulation of tens of ions with site-resolved readout in a one-dimensional Paul trap2–4 and of hundreds of ions with global observables in a two-dimensional (2D) Penning trap5,6. However, integrating these two features into a single system is still very challenging. Here we report the stable trapping of 512 ions in a 2D Wigner crystal and the sideband cooling of their transverse motion. We demonstrate the quantum simulation of long-range quantum Ising models with tunable coupling strengths and patterns, with or without frustration, using 300 ions. Enabled by the site resolution in the single-shot measurement, we observe rich spatial correlation patterns in the quasi-adiabatically prepared ground states, which allows us to verify quantum simulation results by comparing the measured two-spin correlations with the calculated collective phonon modes and with classical simulated annealing. We further probe the quench dynamics of the Ising model in a transverse field to demonstrate quantum sampling tasks. Our work paves the way for simulating classically intractable quantum dynamics and for running noisy intermediate-scale quantum algorithms7,8 using 2D ion trap quantum simulators.In this work, stable trapping of a two-dimensional Wigner crystal of above 500 ions is achieved, and the quantum simulation of 300 ions with individual state detection demonstrated. [ABSTRACT FROM AUTHOR]

Late embryogenesis abundant (LEA) proteins are important for promoting the growth and stress tolerance of plants. They are widely involved in plant growth regulation and responses to hormones and environmental factors. However, knowledge of the functions of the LEA gene in ginseng species remains limited. In this study, a Panax ginseng LEA gene (PgLEA) expression vector was constructed, and stable transgenic Arabidopsis lines were established. The PgLEA protein was classified in the LEA-2 subgroup. Reverse-transcription quantitative PCR analysis showed that the expression of PgLEA increased under 300 mM NaCl or 10 % (m/v) polyethylene glycol treatments. Under salt and osmotic stresses, overexpression of PgLEA in transgenic Arabidopsis plants improved germination rate, root length, and survival rate compared to wild-type plants. In response to drought or salt stress, transgenic plants increased proline accumulation, decreased malonaldehyde content and ion leakage. Furthermore, the transgenic plants exhibited significantly increased activity of superoxide dismutase, peroxidase, and catalase, and reduced accumulation of hydrogen peroxide and superoxide. Moreover, overexpression of PgLEA affected the expression of genes related to salt/drought stress. Taken together, PgLEA is a positive regulator of drought and salinity stress, and positively functioned in pleiotropic effects through regulating osmotic balance, reactive oxygen species scavenging and inducing transcription of stress-related genes. PgLEA may enable ginseng plants to adapt to adverse environments. The data presented herein imply that PgLEA may be useful for breeding new stress-tolerant ginseng cultivars. [ABSTRACT FROM AUTHOR]

Late embryogenesis abundant (LEA) proteins are important for promoting the growth and stress tolerance of plants. They are widely involved in plant growth regulation and responses to hormones and environmental factors. However, knowledge of the functions of the LEA gene in ginseng species remains limited. In this study, a Panax ginseng LEA gene (PgLEA) expression vector was constructed, and stable transgenic Arabidopsis lines were established. The PgLEA protein was classified in the LEA-2 subgroup. Reverse-transcription quantitative PCR analysis showed that the expression of PgLEA increased under 300 mM NaCl or 10 % (m/v) polyethylene glycol treatments. Under salt and osmotic stresses, overexpression of PgLEA in transgenic Arabidopsis plants improved germination rate, root length, and survival rate compared to wild-type plants. In response to drought or salt stress, transgenic plants increased proline accumulation, decreased malonaldehyde content and ion leakage. Furthermore, the transgenic plants exhibited significantly increased activity of superoxide dismutase, peroxidase, and catalase, and reduced accumulation of hydrogen peroxide and superoxide. Moreover, overexpression of PgLEA affected the expression of genes related to salt/drought stress. Taken together, PgLEA is a positive regulator of drought and salinity stress, and positively functioned in pleiotropic effects through regulating osmotic balance, reactive oxygen species scavenging and inducing transcription of stress-related genes. PgLEA may enable ginseng plants to adapt to adverse environments. The data presented herein imply that PgLEA may be useful for breeding new stress-tolerant ginseng cultivars. [ABSTRACT FROM AUTHOR]

For young fishes, growth of somatic tissues and energy reserves are critical steps for survival and progressing to subsequent life stages. When thermal regimes become supraoptimal, routine metabolic rates increase and leave less energy for young fish to maintain fitness-based activities and, in the case of anadromous fishes, less energy to prepare for emigration to coastal habitats. Thus, understanding how energy allocation strategies are affected by thermal regimes in young anadromous fish will help to inform climate-ready management of vulnerable species and their habitat. Blueback herring (Alosa aestivalis) are an anadromous fish species that remain at historically low population levels and are undergoing southern edge-range contraction, possibly due to climate change. We examined the effects of temperature (21°C, 24°C, 27°C, 30°C, 33°C) on survival, growth rate and energy reserves of juveniles collected from the mid-geographic range of the species. We identified a strong negative relationship between temperature and growth rate, resulting in smaller juveniles at high temperatures. We observed reduced survival at both 21°C and 33°C, increased fat and lean mass-at-length at high temperatures, but no difference in energy density. Juveniles were both smaller and contained greater scaled energy reserves at higher temperatures, indicating growth in length is more sensitive to temperature than growth of energy reserves. Currently, mid-geographic range juvenile blueback herring populations may be well suited for local thermal regimes, but continued warming could decrease survival and growth rates. Blueback herring populations may benefit from mitigation actions that maximize juvenile energy resources by increasing the availability of cold refugia and food-rich habitats, as well as reducing other stressors such as hypoxic zones. [ABSTRACT FROM AUTHOR]

Growth rate and energy reserves are important determinants of fitness and are governed by endogenous and exogenous factors. Thus, examining the influence of individual and multiple stressors on growth and energy reserves can help estimate population health under current and future conditions. In young anadromous fishes, freshwater habitat quality determines physiological state and fitness of juveniles emigrating to marine habitats. In this study, the authors tested how temperature and food availability affect survival, growth and energy reserves in juvenile anadromous alewives (Alosa pseudoharengus), a forage fish distributed along the eastern North American continent. Field‐collected juvenile anadromous A. pseudoharengus were exposed for 21 days to one of two temperatures (21°C and 25°C) and one of two levels of food rations (1% or 2% tank biomass daily) and compared for differences in final size, fat mass‐at‐length, lean mass‐at‐length and energy density. Increased temperature and reduced ration both led to lower growth rates, and the effect of reduced ration was greater at higher temperature. Fat mass‐at‐length decreased with dry mass, and energy density increased with total length, suggesting size‐based endogenous influences on energy reserves. Lower ration also directly decreased fat mass‐at‐length, lean mass‐at‐length and energy density. Given the fitness implications of size and energy reserves, temperature and food availability should be considered important indicators of nursery habitat quality and incorporated in A. pseudoharengus life‐history models to improve forecasting of population health under climate change. [ABSTRACT FROM AUTHOR]

The myeloblastosis (MYB) transcription factors are essential for plant stress responses. They can enhance plant tolerance to abiotic stresses (e.g., drought, salinity, and cold) via improved physiological and biochemical responses including the accumulation of metabolites. In this study, we constructed a Panax ginseng MYB4 (PgMYB4) gene expression vector and established the stable transgenic Arabidopsis thaliana lines to study the effects of this gene on plant stress tolerance. The germination rate and seedling taproot length were greater for the PgMYB4-overexpressing plants than for the wild-type plants. Accordingly, the overexpression of PgMYB4 in Arabidopsis enhanced seedling tolerance to drought, salt, and cold conditions. Under drought stress, the relative chlorophyll content decreased less, the proline content increased more, and the water loss rate decreased more in the transgenic plants than in the wild type. The expressions of stress-related genes responsive to dehydration 19A, responsive to dehydration 22, responsive to desiccation 29A, cold-regulated 15A, cold-regulated 47, and pyrroline-5-carboxylate synthase 1 were significantly upregulated in the transgenic Arabidopsis plants. Under high salt stress, the kinesin 1 (KIN1) expression was significantly upregulated in the transgenic plants. In response to the low temperature stress, the dehydration-responsive element binding protein 2A and KIN1 expressions increased dramatically in the transgenic Arabidopsis plants. Thus, PgMYB4 positively regulated the stress tolerance gene networks, which promoted the expression of anti-stress effector genes. This gene may be useful for ginseng breeding programs aiming to develop new cultivars with enhanced stress tolerance. [ABSTRACT FROM AUTHOR]

ViBe algorithm is a powerful moving object detection algorithm. It has many advantages, such as simple method, easy implementation and high computational efficiency, but there are also many shortcomings, such as ghost problem, susceptibility to noise and illumination changes and inadaptability to dynamic scenes. Aiming at the above shortcomings, an adaptive ViBe algorithm based on dispersion coefficients and spatial consistency factor is proposed. Firstly, the mode of multi-frame images is used to replace single image to realize initialization, which reduces the interference of ghost to background model; Secondly, dispersion coefficient is used to establish adaptive dynamic threshold to improve the adaptability of the algorithm to dynamic background; Finally, the spatial consistency factor with spatial information is used to establish adaptive update factor, which reduces the error rate and enhances the robustness of the algorithm. The experimental results show that our improved ViBe algorithm can effectively eliminate ghosts, better adapt to noise, illumination and dynamic background, have more complete detection results and higher detection accuracy than the traditional and others' improved ViBe algorithms and Gaussian mixture model. [ABSTRACT FROM AUTHOR]

Summary: Increased neuropeptide Y (NPY) expression occurred in the glucocorticoid-induced osteoporotic skeleton. NPY knockout mice exhibited a minor response to the glucocorticoid-mediated exacerbation of bone accretion and fatty marrow pathogenesis. NPY deletion restored SITR1 signaling and enhanced PPARγ ubiquitination of bone tissue, an alternative strategy for ameliorating glucocorticoid-induced skeletal deterioration. Introduction: Glucocorticoid excess is observed to worsen the pathogenesis of osteoporosis and fatty marrow. This study was undertaken to investigate the contribution of neuropeptide Y (NPY) to glucocorticoid-induced bone loss and marrow adiposity. Methods: NPY knockout and wild-type mice were administered methylprednisolone for four consecutive weeks. Bone mineral density, microarchitecture, and calcein-labeled mineral acquisition were quantified by μCT, dual energy X-ray absorptiometry, and histomorphometry. Expression of osteogenic and adipogenic markers and acetylation states of PPARγ were detected by RT-quantitative PCR, immunoprecipitation, and immunoblotting. Results: High NPY levels were associated with glucocorticoid-induced trabecular bone deterioration and marrow fat accumulation. Mice lacking NPY had high bone mass concomitant with spacious trabecular and cortical bone microstructure. NPY deletion shielded skeletal tissues from the glucocorticoid-induced impediment of bone mass, trabecular morphometric characteristics, mineral accretion activity, and fatty marrow development. Ex vivo, NPY deficiency sustained osteogenic differentiation capacity and curtailed the glucocorticoid-mediated escalation of adipocyte formation reactions of primary bone-marrow mesenchymal cells. NPY deletion appeared to modulate Y1 and Y2 receptors, sirtuin 1, ERK, and p38 signaling pathways, an effect that facilitated hypoacetylation and ubiquitination of adipogenic transcription factor PPARγ in the skeletal tissues exposed to glucocorticoid stress. Conclusions: NPY mediates the glucocorticoid-induced disturbance of mineral accretion and marrow adipogenesis through post-translational modification of PPARγ. This study brings a new molecular insight into the disintegration of adipogenic and osteogenic activities within glucocorticoid-mediated osteoporotic skeletons. Control of NPY is an alternative strategy to ameliorate glucocorticoid-induced bone destruction and fatty marrow. [ABSTRACT FROM AUTHOR]

Introduction: Out-of-hospital cardiopulmonary arrest (CPA) in children is rare but significant, with poor survival rates and high morbidity. Asystole is the most common dysrhythmia, and cardiopulmonary resuscitation (CPR) is of great importance in such cases. We aimed to survey the knowledge, attitudes and perceptions of parents in Singapore regarding infant basic life support (IBLS).Methods: A questionnaire survey was administered to parents of children managed at the Neonatal Department of Singapore General Hospital, Singapore, between 1 September and 31 December 2008. The questionnaire consisted of three sections--section A collected demographic data, section B included questions on knowledge, and section C explored attitudes and perceptions. Knowledge T-scores were analysed for the entire cohort and subanalysed with respect to prior IBLS training.Results: In our study cohort (n = 375), the median Basic Knowledge (BK) T-score was 7 (range 1-9) and the pass rate was 55%. Median BK T-scores were significantly different between untrained (6; range 3-9) and previously trained (8; range 3-9) participants. A majority of the trained participants obtained pass marks. Median Total Knowledge T-score, involving advanced questions, for previously trained participants was 11 (range 3-14), but pass rate was low (35.7%). Higher educational qualification was a significant factor impacting all scores. Untrained participants indicated interest in attending IBLS courses, while trained participants were interested in refresher courses.Conclusion: IBLS training, as part of basic cardiac life support training, is important given that CPR can significantly alter the outcome in children with CPA. Our survey revealed knowledge gaps that could be bridged through formal training. Refresher courses to regularly update parents' knowledge are recommended. [ABSTRACT FROM AUTHOR]

InFlood!, Eric Drooker reveals himself as a unique comics artist, presenting an affirmative worldview amid an increasingly apocalyptic landscape. Exploring the resultant sense of duality between a harsh reality and a hopeful future, Drooker’s vision manifests through his extensive use of music imagery. In the context ofFlood!, music adds a venue for such dual messages, as well as for forging a sense of human connectedness rooted in music’s own universality. Furthermore, music acts as an additional factor working alongside the traditional comics blend of words and images. It is also worth noting how music and comics function in terms of audience perception. Both media have a ‘synesthetic’ nature, engaging multiple senses in a way conducive to multiplicities of meaning. Furthermore, they share a significant capacity to engage readers and listeners cognitively, and this contributes toFlood!’s thematic progressivism. [ABSTRACT FROM AUTHOR]

Objective Type-2 diabetes is mainly the metabolic defect involving multiple organs. To conclude their intricate relationships, the term 'ominous octet' had been proposed to denote this phenomenon. In this study, we enrolled older men without any medications for MetS components to further elucidate the relationships between normoglycaemic state and MetS. Methods We enrolled male subjects with FPG less than 100 mg/dl and aged 65 and older undergoing routine health check-ups in Taiwan. After excluding subjects taking medications that might affect the components of MetS, a total of 6679 men were eligible for the analysis. Study subjects were further grouped into FPG tertiles (< 91 mg/dl, 92-95 mg/dl and > 95 mg/dl for tertil 1, tertil 2 and tertil 3, respectively). Results There was a significant trend between the FPG and percentages of subjects having MetS (p = 0.009). The relationships between the MetS components were higher in FPG 2 and FPG 3 than FPG 1. In simple correlation, all of the MetS and LDL-C were positively correlated with FPG level and multiple regression further confirmed the same result except for HDL- C that became non-significant. Subjects in FPG3 had significantly higher ORs ( ORs = 1.19) for having MetS than those in FPG1. Conclusions In conclusion, higher FPG still had higher risk of having MetS in normoglycaemic range in elderly male. More strict FPG level control may be valuable in CVD prevention and warrants further investigations. [ABSTRACT FROM AUTHOR]

In material science, images are increasingly used as input data for computational models. In most of the published papers, voxel-based finite element models are employed using a mesh that is automatically built by converting each voxel into a finite element. We have recently proposed (Legrain et al., Int J Numer Methods Eng 86(7): 915-934, ) another computational approach for incorporating images in models, based on the extended finite element method (X-FEM) and levelsets. Its main advantages are that the mesh does not need to conform to the geometry and that a smooth representation of physical surfaces is obtained. The aim of this paper is to compare the two approaches in the framework of computational homogenization in elasticity, starting from material microstructural images. Attention will be paid to geometrical approximations, macroscopic properties and local quantities (e.g. stress oscillations, local error etc.). It is shown that the X-FEM/levelset approach is more efficient than voxel-based FEM. [ABSTRACT FROM AUTHOR]

Objective: To provide the anatomical basis for the feasibility and clinical practice of lengthened sacroiliac screw fixation, by measuring various related indicators of the safe insertion regions of S1 and S2 lengthened sacroiliac screws.Methods: A total of 66 healthy pelvises of adults were scanned by 64-slice spiral CT and the length, width and height of the safe insertion regions for S1 and S2 lengthened sacroiliac screw were measured. The safe screw entrance point locations were described with a quantitative method. The indicators were recorded by descriptive statistics and the statistics of left and right sides, segments of S1 and S2, and different layers (including top, middle and bottom parts) of S1 and S2 were compared.Results: The lengths of ilium within the safe insertion regions for lengthened screws are more than 16 mm. The width and height of the safe insertion region of S1 and S2 are almost all more than 7.3 mm. Generally, the width and height of S1 are larger than those of S2. The reference ranges of the best/safest entrance point locations of lengthened sacroiliac screws are as follows-S1: 42.21-63.69 mm in front of posterior superior iliac spine, 32.77-53.75 mm above the highest point of the greater sciatic notch; S2: 22.68-54.28 mm in front of posterior superior iliac spine, 14.06-33.70 mm above the highest point of the greater sciatic notch.Conclusion: (1) There is anatomical feasibility for the placements of S1 and S2 lengthened sacroiliac screws. (2) φ 7.3-mm partial thread cannulated screw (thread length 16 mm) and φ 6.5-mm partial thread cancellous screw(thread length 16 mm) can be used as lengthened sacroiliac lag screw. (3) The safe insertion space of S1 is larger than that of S2. (4) There is safe space for placement of at least one piece of lengthened sacroiliac screw in both S1 and S2. (5) The best/safest entrance points of S1 and S2 can be approximately located with anatomical landmarks. [ABSTRACT FROM AUTHOR]

The discovery of postnatal mesenchymal stem cells (MSC) with their general multipotentiality has fueled much interest in the development of cell-based therapies. Proper identification of transplanted MSC is crucial for evaluating donor cell distribution, differentiation, and homing. Lack of an efficient marker of transplanted MSC has precluded our understanding of MSC-related regenerative studies, especially in large animal models such as pigs. In the present study, we produced transgenic pigs harboring an enhanced green fluorescent protein (EGFP) gene. The pigs provide a reliable and reproducible source for obtaining stable EGFP-labeled MSC, which is very useful for donor cell tracking after transplantation. The undifferentiated EGFP-tagged MSC express elevated levels of EGFP while maintaining MSC stemness. These cells exhibited homogeneous surface epitopes and possessed classic tri-lineage differentiation potential into osteogenic, adipogenic, and chondrogenic lineages, with robust EGFP expression maintained in all differentiated progeny. Injection of donor MSC can dramatically increase thickness of infarcted myocardium and improve cardiac function in mice. Moreover, the MSC with their strong EGFP expression can be easily distinguished from the background autofluorescence in myocardial infarcts. We demonstrated an efficient, effective, and easy way to identify MSC after long-term culture and transplantation. With the transgenic model, we are able to obtain stem/progenitor cells in earlier passages compared to transfection of traceable markers into established MSC. As the integration site of the transgene is the same for all cells, we have lessened the potential for positional effects and the heterogeneity of the stem cells. The EGFP-transgenic pigs may serve as useful biomedical and agricultural models of somatic stem cell biology. [ABSTRACT FROM AUTHOR]

Objectives: Isolation of mouse mesenchymal stem cells (mMSCs), by the approach of plastic adherence, has been difficult due to persistent contamination by haematopoietic cells (HCs); we have observed that this contamination was due to engagement between HCs and mMSCs. The HCs can be lifted together with the mMSCs despite their insensitivity to trypsin digestion. Herein, we provide a single-step procedure to rapidly segregate mMSCs from HC contaminants using transient lower-density plastic adherence (tLDA). Materials and methods: The tLDA was performed by replating bone marrow adherent cells at lower density (1.25 × 104 cells/cm2) than usual, allowing for transient adherence of no more than 3 h, followed by trypsin digestion. tLDA-isolated cells were evaluated by immunophenotyping, multi-differentiation potentials, immunosuppressive properties, and therapeutic potential as demonstrated by symptoms of osteoporosis. Results: The single-step tLDA method can effectively eliminate the persistent HC contaminants; tLDA-isolated cells were phenotypically equivalent to those reported as mMSCs. The isolated cells possessed classic tri-lineage differentiation potential into osteogenic, adipogenic and chondrogenic lineages and had immunosuppressive properties. After intravenous transplantation, they migrated into the allogeneic bone marrow and rescued hosts from osteoporosis symptoms, demonstrating their therapeutic potential. Conclusions: We have developed a simple and economical method that effectively isolates HC-free, therapeutically functional mMSCs from bone marrow cell adherent cultures. These cells are suitable for various mechanistic and therapeutic studies in the mouse model. [ABSTRACT FROM AUTHOR]

Disassembly of DNA–ligands, including DNA–methylene blue (MB) complex and DNA–Co(phen)33+ complex on mica surface, were investigated by atomic force microscopy (AFM). The disassembly of these complexes occurred after they were immersed in ultra-pure water. AFM results showed that the disassembly depended strongly on bridge ions that were used to immobilize the complex onto mica surface, DNA species and ligands. When Mg2+ was used as the bridge ion, the DNA–MB complex was completely disassembled because of the weak interactions between Mg2+ and DNA's bases or mica surface. Although if Co2+ was used as the bridge ion, the disassembly of the DNA–MB complex mainly depended on the species and shape of DNA. For plasmid DNA pBR 322, plasmid DNA pUC 18 and the linear DNA pBR 322/PstI, the degree of disassembly was gradually increased. Whereas if Co(phen)33+ was chosen as the ligand, the disassembly of the DNA–Co(phen)33+ complex was almost blocked because Co(phen)33+ could hardly diffuse into the ultra-pure water. This obtained information may be useful for practical application of the AFM imaging of biological molecules, especially in liquid. [ABSTRACT FROM AUTHOR]

We sought to clarify whether impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or both (IFG/IGT) represent the most severe impairment in insulin resistance (IR) and insulin secretion. Among the 159 Chinese subjects, 21 were diagnosed as having IFG, 103 as having IGT and 35 as having both. IR and beta-cell function were assessed using homeostatic model assessment (HOMA) and an insulin-suppression test (IST). No differences were evident between the groups in blood pressure, body mass index, plasma insulin fasting levels and lipid profiles. However, plasma 2-h insulin levels were higher in the IGT and IFG/IGT groups. Beta-cell functions were not different between these groups. But, the result of glucose tolerance was different, in which the IFG/IGT and IFG groups displayed higher insulin sensitivity than IGT via HOMA instead of no difference via IST in the three patient groups. [ABSTRACT FROM AUTHOR]

Objective: To examine whether 17-β-oestradiol (E2) may alter angiotensin II (Ang II) induced cell proliferation and to identify the putative underlying signalling pathways in rat cardiac fibroblasts. Design: Cultured rat cardiac fibroblasts were preincubated with E2 then stimulated with Ang II. [³H] Thymidine incorporation and endothelin-1 (ET-1) gene expression were examined. The effect of E2 on Ang II induced NADPH oxidase activity, reactive oxygen species (ROS) formation, and extracellular signal regulated kinase (ERK) phosphorylation were tested to elucidate the intracellular mechanism of E2 in proliferation and ET-1 gene expression. Results: Ang II increased DNA synthesis, which was inhibited with E2 (1-100 nmol/l). E2, but not 17-α- oestradiol, inhibited Ang II induced ET-1 gene expression as shown by northern blotting and promoter activity assay. This effect was prevented by co-incubation with the oestrogen receptor antagonist ICI 182 780 (1 μmol/1). E2 also inhibited Ang II increased NADPH oxidase activity, ROS formation, ERK phosphorylation, and activator protein-1 mediated reporter activity. Conclusions: The results suggest that E2 inhibits Ang II induced cell proliferation and ET-1 gene expression, partially by interfering with the ERK pathway through attenuation of ROS generation. Thus, this study provides important new insight regarding the molecular pathways that may contribute to the proposed beneficial effects of oestrogen on the cardiovascular system. [ABSTRACT FROM AUTHOR]

Background/objectives: Female sex workers and their male clients have been identified as risk groups for the transmission of STDs and HIV. Behavioural interventions targeting clients need to address inconsistent condom use among them. The aim of the study is to assess the sociodemographic, behavioural, and psychological factors associated with inconsistent condom use among clients of sex workers. Methods: 229 male patients attending the STD clinic in Singapore who reported paying for sex in the previous 6 months were interviewed. Response rate was 91%. Results: Overall, 45% used condoms inconsistently; these clients were more likely to have poor STD knowledge, visit sex workers five or more times in the past 6 months, have lower self efficacy, less favourable social norms for condom use, and more likely to forget condom use when intoxicated (alcohol impaired decision making). Conclusions: Behavioural interventions for clients need to improve STD/HIV transmission knowledge and focus on improving client's self efficacy in using condoms. [ABSTRACT FROM AUTHOR]

Summary Nervous disorders were found in two horses and verified as aseptic encephalitis by necropsy in the summer of 2000. To investigate agents that affected the horses, diagnostic procedures involving virus isolation, neutralization test and reverse transcription–polymerase chain reaction (RT-PCR) were performed. We intracranially inoculated litters of suckling mice with tissues suspected of containing aseptic encephalitis, including cerebrum, cerebellum, brain stem, thalamus, and cerebrospinal fluids; the mice were then observed for 14 days. Neutralizing antibodies against Japanese encephalitis (JE) viruses were present in the cerebrospinal fluid of the horses in titers of 10. Sequences of 500 nucleotides of the premembrane gene of JE virus, synthesized by RT-PCR, from both the cerebrum and cerebellum were determined. The phylogenetic analysis based on sequences of the premembrane gene revealed a relationship with the JE virus. The divergences at the nucleotide level of 1.2–5.7% and at the amino acid level of 0–4.3% were conserved with other JE strains. The results demonstrated that the pathogens causing equine encephalitis were JE viruses. The strains were closely related to Taiwanese isolates. [ABSTRACT FROM AUTHOR]

The needles of ponderosa pine (Pinus ponderosa Laws.) were reported to induce abortions when fed to late-term pregnant beef cows in North America. An in vivo study of pregnant cows suggested that isocupressic acid (IA) was the main abortifacient isolated from needles and bark of the pine. However, the mechanism of abortifacient activity of IA is not clear yet. In a pregnant cow, the corpus luteum of the ovary helps the maintenance of pregnancy by its progesterone production. This study involved the IA extracted from the root of the Taiwan cypress (Juniperus formosana) and used a frozen-thawed bovine luteal cell culture system to investigate the action of IA on progesterone production. Thawed bovine luteal cells (1 × 10[sup 5] cells/ml/well) in M199 medium were cultured in 24-well culture plates at 37°C in a 5% CO[sub 2] incubator. Ten ml of tested drugs, IA at 1 to 1000 ng/ml and/or ovine luteinizing hormone (oLH) at 1 to 100 ng/μl or 8-bromo-cyclic adenosine monophosphate (8-Br-cAMP) with 0.1-10 mM, were added into each well. After 4 hours of incubation, the media were harvested and assayed for progesterone by an enzyme immunoassay. Progesterone production from cells was the indicator used to evaluate the action of IA. All tested doses of IA significantly inhibited progesterone production in both basal and oLH stimulating conditions. Also those dosages inhibited cyclic adenosine-3', 5'- monophosphate (cAMP) stimulation, suggesting a post-cAMP mechanism is involved in the IA action. We concluded that IA can induce pregnant cows to abort partly through blocking luteal function and may be identified as a new abortifacient chemical. [ABSTRACT FROM AUTHOR]

Three ultrafine silver iodobromide emulsions with the same iodide contents (0.3 mol%) were prepared. Their sizes were determined by transmission electron microscopy and X-ray diffraction, which proved that their sizes were about 30, 50 and 100 nm respectively. The emulsions showed the 'quantum-size effect', in that their absorption peaks shifted to short wavelengths with decreasing grain size and their sensitivities were far lower than those of normal emulsions. However, the sensitivities of these emulsions were increased significantly when they were reduction sensitized with (NH2)2CSO2, which was more effective than sulphur, gold and sulphur-plus-gold sensitization. The smaller the grain sizes, the better was the reduction-sensitized effect for these ultraline grain emulsions. It was also observed that the ionic conductivities were directly proportional to the surface area volume ratio of the grains; i.e. for cubic grains the ionic conductivity was inversely proportional to the edge length of the grain, d. Similarly the photoelectron lifetimes were directly proportional to the cubic grain edge length d. The result of low-temperature (77 K) fluorescence also demonstrated that recombination of positive holes and photoelcctrons increased as the grain size decreased. [ABSTRACT FROM AUTHOR]

Sixty-three male cigarette smokers were entered into a cross-sectional study to determine whether inverse associations existed between polycydlic aromatic hydrocarbon (PAH)—DNA adduct levels and intake/serum levels of vitamin A, vitamin C and vitamin E. Associations between PAH–DNA adducts and intakes of carotene, as well as serum levels of β-carotene, were also determined. Fasting blood samples were collected for assays of PAH—DNA adducts in circulating mononuclear cells, plasma cotinine and serum levels of vitamin A, β-carotene, vitamin C and vitamin E. Since genetic deficiency in the detoxifying enzyme glutathione S-traasferase M1 (GSTM1) has been associated with increased risk of lung cancer, GSTM1 genotype was also determined. Analysis of PAH—DNA adducts by competitive enzyme-linked immunosorbent assay (ELISA) indicated that 70% of the subjects had detectable adducts, with a mean of 4.38 adducts/10 nucleotides (range 1.00–24.1/10 Pearson's method was utilized to determine whether any associations existed between the various host variables and PAH—DNA adducts. Previously, no significant associations were found between PAH—DNA adducts and cigarettes smoked/day, pack-years, daily/life time tar exposures or plasma cotinine levels (Santella , 13, 2041–2045, 1992). PAH—DNA adducts were inversely associated with serum cholesterol-adjusted vitamin E levels ( = −0.25, ≤ 0.05) and with smoking-adjusted vitamin C serum levels ( = −0.22, ≤ 0.09). Stratification by GSTM1 genotype indicated that these associations were limited to subjects with the null genotype. The relationship between adducts and serum cholesterol-adjusted vitamin E was significant in those of the null genotype ( = −0.38, ≤ 0.04), but not in those with the gene present ( = −0.12, = 0.5). Similarly, for smoking-adjusted vitamin C, the relationship with adducts was stronger in subjects with the null genotype ( = −035, ≤.0.06) than in those with GSTM1 present ( = −0.05, = 0.77). These results are consistent with findings of prior epidemiological studies Identifying significant inverse associations between anti-oxidant micronutrient status or GSTM1 genotype and the incidence of lung cancer. Additional studies should be conducted to confirm a possible role for vitamin E in PAH—DNA adduct formation and to explore further the possible roles of vitamin A, β-carotene and vitamin C in modulating adduct formation and lung cancer risk. [ABSTRACT FROM PUBLISHER]

The adaptive iterated particle filter (AIPF) is presented, where the importance density function is updated iteratively by the particle filter itself when necessary. By using a simulated annealing algorithm with an adaptive annealing parameter, the current measurement can be quickly incorporated into the sampling process, resulting in greatly improved sampling efficiency. Simulation results demonstrate the improved performance of the AIPF over the sampling importance resampling filter, unscented Kalman particle filter and auxiliary particle filter. [ABSTRACT FROM AUTHOR]