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Stable suspensions of gold nanorods in 4-cyano-4′-pentylbiphenyl (5CB) have been prepared by capping the nanoparticles with polyethylene glycol (PEG). Small angle X-ray scattering has been used to characterize the orientational order of the gold nanorods and the properties of any aggregates. It was found that the nanorods had a very high degree of orientational order with respect to the director of the 5CB matrix and this could be redirected by an applied electric field at 2kHz. Two different PEG molecular weights were investigated and it was found that the lower (1.9kDa) gave exceptionally high order parameters, above 0.9. [ABSTRACT FROM AUTHOR]

Issue addressed: Australian university students consume large amounts of alcohol. There is little published information about personal and academic problems associated with this behaviour. We sought to estimate the prevalence, and identify variables associated with, alcohol-related problems among undergraduate hazardous drinkers. Methods: The control group members (942 undergraduates, 53.3% male, mean age 19.4 years) of an internet-based intervention trial, who scored ≥8 on the Alcohol Use Disorders Identification Test, completed two validated questionnaires about their experience of alcohol-related problems in the preceding 4 weeks. Regression models were used to identify associations between individual characteristics and alcohol-related problems. Results: One-quarter of participants had missed a class (25.6%) and/or had been unable to concentrate in class (25.7%), and 45% reported that their drinking had impacted negatively on their learning or grades. The most frequent non-academic problems were hangovers (74.8%), blackouts (44.8%), emotional outbursts (30.5%), vomiting (28.1%), arguments (20.2%) and drink-driving (23.2%). Male gender, lower age, being a smoker, being in the Faculty of Health (versus Humanities) and living in shared housing (versus with parents/guardians) were each associated with alcohol-related problems, whereas year of study had no association. Conclusions: There is a high prevalence of preventable alcohol-related problems among undergraduates drinking at hazardous levels and a need for restriction of the availability and promotion of alcohol as well as intervention for individuals at high risk. So what? Universities have a duty of care to large populations of young people drinking at hazardous levels and should make greater efforts to address hazardous alcohol consumption. [ABSTRACT FROM AUTHOR]

Abstract: An atmospheric electric field exerts a torque on both column and plate ice crystals. Columns tend to align along the direction of the field. One diameter of plate crystals also aligns parallel to a field, while a non-uniform diverging field leads to further orientation and proscribes a secondary orientation along the direction of least divergence. A laboratory investigation treats the electrical orientation of thin plate ice crystals in a non-uniform field as a two-step process. In the model, the average field provides the primary torque and aligns one diameter of the plate crystal while simultaneously a spatially varying component of the field aligns the perpendicular diameter. The first element of the process, the primary torque, has been investigated previously. The complete reorientation, caused by a secondary torque, is investigated herein. Experimentally a stronger field with sufficient non-uniformity is required to demonstrate the secondary torque. The realignment caused by this torque depends also on the strength of the aerodynamic torques on the falling ice crystals. Experiments in a laboratory cold chamber with small thin plate crystals in an electric field provided by a charged rod demonstrate crystal reorientation by changing the reflections of a beam of white light. A model incorporating electrical torques is applied to the laboratory observation and used to investigate the possibility of the effects occurring in the atmosphere. Fields near lightning strokes, which are strong but of short duration, may reorient small crystals. Larger crystal aggregates like planar snowflakes are governed by the same electrical torques. It is suggested that the secondary torque realignment might be observable for aggregates large enough to be detected by radar in cases pertaining to weaker but longer duration fields associated with cloud electrification. A simplification of the model is used to investigate electrically caused crystal motion and linear aggregation, with applications to the atmosphere and to lightning initiation. [Copyright &y& Elsevier]

Melting, freezing, and evaporation of individual and aggregates of snow crystals are simulated in the laboratory under controlled temperature, relative humidity, and air velocity. Crystals of selected habit are grown on a vertical filament and subsequently melted or evaporated in reverse flow, with the velocity adjusted for appropriate fall speed to reproduce conditions of the melting layer. Nonequilibrium conditions are simulated for larger melting ice particles surrounded by smaller drops at a temperature up to +5°C or growth of an ice crystal surrounded by freezing ice particles down to -5°C. Initial melting of well-defined faceted crystals, as individuals or in combination, occurs as a water layer >10 μm thick. For larger (>100 μm) crystals the water becomes sequestered by capillary forces as individual drops separated by water-free ice regions, often having quasiperiodic locations along needles, columns, or arms from evaporating dendrites. Drops are also located at intersections of aggregate crystals and dendrite branches, being responsible for the maximum of the radar scatter. The drops have a finite water–ice contact angle of 37°–80°, depending on ambient conditions. Capillary forces move water from high-curvature to low-curvature regions as melting continues. Toward the end of the melting process, the ice separating the drops becomes sufficiently thin to fracture under aerodynamic forces, and mixed-phase particles are shed. Otherwise ice-free drops are shed. The melting region and the mechanism for lowering the melting layer with an increasing precipitation rate are associated with smaller ice particle production capable of being lofted in weaker updrafts. [ABSTRACT FROM AUTHOR]

Abstract Translocation of animals to re-establish extirpated populations or to maintain declining ones has often been carried out without genetic information on source or target populations, or adequate consideration of the potential effects of mixing genetic stocks. We consider the conservation status of the fisher (Martes pennanti ) and evaluate the potential genetic consequences of past and future translocations on this medium-sized carnivore by examining population variation in mitochondrial control-region sequences. We sampled populations throughout the fisher's range in North America including five populations unaffected by translocations and two western populations that had received long-distance translocations. Twelve haplotypes showed little sequence divergence. Haplotype frequencies differed significantly among subspecies and between populations within subspecies. Analysis of molecular variance (amova) and neighbour-joining analyses of haplotype relationships revealed population subdivision similar to current subspecies designations, but which may reflect an isolation-by-distance pattern. Populations in Oregon and in Montana and Idaho received several translocations and each showed greater similarity to the populations where translocations originated than to adjacent populations. Additional sequences obtained from museum specimens collected prior to any translocations suggest historical gene flow among populations in British Columbia, Washington, Oregon, and California. Anthropogenic impacts in that region have greatly reduced and isolated extant populations in Oregon and California. Future translocations may be necessary to recover populations in Washington and portions of Oregon and California; our results indicate that British Columbia would be the most appropriate source population. [ABSTRACT FROM AUTHOR]

Orientation of ice crystals in the form of thin plates (diameter up to 30 μm, thickness 0.5 to a few μm) was investigated optically for crystals nucleated in a supercooled cloud in a laboratory cold chamber. Random orientation caused by Brownian rotation of small crystals (apparent as twinkling) and alignment caused by airflow resulting from fall motion of larger crystals was changed by application of an electric field either as a step or as an oscillating square wave of variable frequency of order 1–10 Hz. Video records and time exposed still photographs demonstrated crystal fall, oscillation, and orientation changes with electric field magnitude and frequency. Thin film interference colours provided crystal thickness, mass, and moment of inertia. Realignment began for electric fields greater than 0.5–1 kV/m and was complete above 10 kV/m. Measurements of degree of alignment (from random orientation to completely parallel to the electric field) and its time dependence (of order tenths of seconds) are consistent with predictions of a theoretical oscillator model based on electrical torques on ellipsoids in viscous air. In a changing electric field at low frequency, the crystal realignment varies along with the variation field and at high frequency they remain aligned along the average field. These results are applied to larger crystals as occur in the atmosphere with implication for remote sensing of ice by radar and lidar as influenced by local electric fields and with the possibility of their remote measurement by optical observation of changing crystal orientations. [Copyright &y& Elsevier]

Context: Managing thoracic aortic aneurysms identified incidentally by increased use of computed tomography, echocardiography, and magnetic resonance imaging is problematic, especially in the elderly.Objective: To ascertain whether the previously reported poor prognosis for individuals with thoracic aortic aneurysms has changed with better medical therapies and improved surgical techniques that can now be applied to aneurysm management.Design: Population-based cohort study.Setting and Patients: All 133 patients with the diagnosis of degenerative thoracic aortic aneurysms among Olmsted County, Minnesota, residents between 1980 and 1994 compared with a previously reported cohort of similar patients between 1951 and 1980.Main Outcome Measures: The primary clinical end points were incidence, cumulative rupture risk, rupture risk as a function of aneurysm size, and survival.Results: In contrast to abdominal aortic aneurysms, for which men are affected predominately, 51% of thoracic aortic aneurysms were identified in women who were considerably older at recognition than men (mean age, 75.9 vs 62.8 years, respectively; P= .01). The overall incidence rate of 10.4 per 100000 person-years (95% confidence interval [CI], 8.6-12.2) between 1980 and 1994 was more than 3-fold higher than the rate from 1951 to 1980. The cumulative risk of rupture was 20% after 5 years. Seventy-nine percent of ruptures occurred in women (P= .01). The 5-year risk of rupture as a function of aneurysm size at recognition was 0% for aneurysms less than 4 cm in diameter, 16% (95% CI, 4%-28%) for those 4 to 5.9 cm, and 31% (95% CI, 5%-56%) for aneurysms 6 cm or more. Overall 5-year survival improved to 56% (95% CI, 48%-66%) between 1980 and 1994 compared with only 19% between 1951 and 1980 (P<.01).Conclusions: In this population, elderly women represent an increasing portion of all patients with clinically recognized thoracic aortic aneurysms and constitute the majority of patients whose aneurysm eventually ruptures. Overall survival for thoracic aortic aneurysms has improved significantly in the past 15 years. [ABSTRACT FROM AUTHOR]

Lipids and metabolites can be directly detected from biological samples by desorption electrospray ionization mass spectrometry (DESI-MS). The introduction of morphologically friendly solvent systems allows nondestructive analysis of samples and because of its extractive nature, ion intensities obtained are adequate for profiling microscopic samples. This work reports the individual chemical profiling of mouse oocytes and diverse pre-implantation developmental stages of embryos by DESI-MS. Mice were superovulated with 5 IU pregnant mare serum gonadotropin (PMSG) IP followed 46 h later by 5 IU hCG IP and mated or not for embryo and oocyte recovery, respectively. Mice were killed and their oviducts removed and flushed at different intervals post-hCG to collect oocytes and embryos at different stages of development. Two-cell embryos were also cultured in vitro to obtain additional samples. For MS analysis, samples (n = 63) were taken from the flushing or culture medium, washed briefly in distilled water and placed on a glass slide for same-day analysis. Mass spectra were acquired in the negative ion mode at the mass/charge range of m/z 150 to 1000 using 1:1 (v/v) acetonitrile/DMF as a solvent system in an LTQ linear ion trap mass spectrometer (ThermoFisher Scientific, Pittsburgh, PA). Mass spectra from oocytes (n = 11) as well as zygotes (n = 9), 2-cell (n = 11), 4-cell (n = 1), 8- to 16-cell (n = 19) embryos and blastocysts (n = 12) showed the presence of deprotonated free fatty acids such as palmitic (m/z 255.2), linoleic (m/z 281.2), arachidonic (m/z 303.3) and docosahexanoenic (m/z 327.3), as well as prominent fatty acid dimers in the region of m/z 500 to 650, such as m/z 563.5 (oleic acid dimer) and glycerophospholipids in the m/z 700 to 1000 range. These complex lipids were represented by chlorinated phosphocholines such as PC 34:1, m/z 794.7; phosphatidylinositols such as PI 38:4, m/z 885.8; phosphatidylethanolamines such as PE 38:3, m/z 768.7; and phosphatidylserines such as PS 38:4, m/z 810.7. After analysis, samples observed on the glass slide displayed evident dehydration caused by the action of the organic solvent. Chemical profiling was more difficult for oocytes and blastocysts compared with other developmental stages, probably because of the presence of the intact zona pellucida in oocytes, whereas blastocysts were more prone to lysis during the rapid water wash, leading to a decrease in signal intensity. Optimization of conditions, comparison of MS spectra from a greater number of samples of different developmental stages by multivariate statistics and the influence of in vitro vs in vivo conditions are currently being investigated. Although small molecules have been shown to play a role in the direction of cell fate, the mechanisms involved are poorly understood. Perspectives for the application of this novel DESI-MS technique include the ability to study chemical signatures of hierarchical pluripotency observed during early embryonic development including embryonic stem cell differentiation. Support from the Purdue University Center for Cancer Research Small Grants Program is gratefully acknowledged. [ABSTRACT FROM AUTHOR]

We present a study of the reactions of aldehydes in ionic liquids which gives evidence for the spontaneous formation of N-heterocyclic carbenes in ionic liquids based on 1,3-dialkyl substituted imidazolium cations from the lack of a deuterium isotope effect on the reaction of these ionic liquids with aldehydes. [ABSTRACT FROM AUTHOR]

Ionicliquids have been shown to have application in several areasof importance in the context of sustainable industrial activity. Oneapplication of particular interest is the ability of certain ionicliquids to dissolve biomass. This clearly marks them as useful materialswith application within biorefineries. In this contribution, we presentnew coarse-grained soft-SAFT models and experimental density dataof chloride (Cl–), methylsulfate ([MeSO4]−), and dimethylphosphate ([Me2PO4]−) based ionic liquids which are relevantfor biomass deconstruction processes. Model parameters were obtainedby fitting to pure component temperature density data, and the modelswere subsequently tested by assessing their ability to accuratelycalculate viscosity and interfacial surface tension. We also developedmodels of mixtures of the ionic liquids with water and short-chainlinear alcohols. We decomposed the contributions to the excess Gibbsenergy of mixing to chemical and structural contributions, and usedthis to provide some insight into the driving forces for solubilityof molecular species in these ionic liquids. [ABSTRACT FROM AUTHOR]

Vitamin D is anticipated to have many extra-skeletal health benefits. We questioned whether supplementation with the vitamin influenced body weight and composition. A systematic review and meta-analysis was conducted on high-quality, randomized controlled trials ( RCTs) that had supplemented vitamin D without imposing any caloric restriction. Eighteen trials reporting either body weight, body mass index ( BMI), fat mass ( FM), percentage fat mass (% FM) or lean body mass ( LBM) met our criteria. Twelve studies provided the required data for the meta-analysis. Vitamin D supplementation did not influence the standardized mean difference ( SMD) for body weight, FM, % FM or LBM. A small but non-significant decrease in BMI ( SMD = −0.097, 95% confidence interval: [−0.210, 0.016], P = 0.092) was observed. Meta-regression confirmed that neither the absolute vitamin D status achieved nor its change from baseline influenced the SMD of any obesity measure. However, increasing age of the subjects predicted a shift in the SMD for FM towards the placebo treatment, whereas a greater percentage of women in these studies favoured a decrease in FM following vitamin D. Vitamin D supplementation did not decrease measures of adiposity in the absence of caloric restriction. A potential confounding by age and gender was encountered. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) allows the detection and structural characterisation of intact molecules such as fatty acids and complex lipids. Desorption electrospray ionization (DESI) is an ambient ionization technique used for MS analysis and profiling and imaging of drugs, metabolites and lipids directly from biological samples with no sample preparation. With the recent introduction of morphologically friendly DESI-MS solvent systems, it is also possible to acquire DESI-MS data non-destructively. Due to the extractive nature of these solvent combinations, enough ion intensity can be generated to chemically profile samples of microscopic dimensions. The objective of this work was to perform chemical profiling on intact bovine blastocysts by DESI-MS, focusing on lipid distributions. Blastocysts produced in vitro were washed 3 times in PBS + 0.1% polyvinyl alcohol to remove lipids present in the culture medium, were placed in PBS/methanol 50% and stored under -20°C for 1 week. For DESI-MS analysis, the embryos were simply placed in glass slides and allowed to dry at room temperature. Mass spectra were acquired in the negative ion mode at the mass/charge range from m/z 150 to 1000, using as solvents a combination of 1:1 (vol/vol) ethanol:dimethylformamide (DMF) or acetonitrile:DMF. The mass spectrometer used was a LTQ linear ion trap mass spectrometer controlled by Xcalibur 2.0 software (Thermo Fisher Scientific, San Jose, CA, USA). The lipid species detected included deprotonated free fatty acids such as palmitic acid (m/z 255.2), stearic acid (m/z 283.2), arachidonic acid (m/z 311.2) and docosanoic acid (m/z 339.3). Free fatty acid dimers appear in the region from m/z 500 to 650 and complex lipids represented mainly by glycerophospholipid classes appear in the region from m/z 700 to 1000 and include phosphatidylinositols (PI 38:1; m/z 788.7), phosphatidylserines (PS 36:1, m/z 885.7) and also the chlorinated phosphatidylcholines (PC 36:1; m/z 794.7). After recording the mass spectra, embryos could still be observed in the glass slide with evident dehydration due to the action of the organic solvent. Since lipid composition of bovine embryos is closely related to cryosensitivity and due to the limited amount of analytes (each embryo is estimated to have a mass of 15 pg of total lipids) lipid analysis usually involves the pooling of individuals to have a large enough amount of analytes. Traditionally, gas chromatography is used for fatty acid residue analysis in oocytes and embryos pooled are submitted to lipid extraction and derivatization. Mass spectrometry by DESI, however, allows direct analysis of intact and single embryos and the profiling of not only free fatty acids but also complex lipids, represented mainly by 3 glycerophospholipid classes (PC, PI and PS). We envisage that DESI-MS will likely become a routine tool for the analysis of lipid composition in mammalian embryos and will contribute significantly to the development of culture systems that produce embryos with higher cryoresistance. Support from the Purdue University Center for Cancer Research Small Grants Program is gratefully acknowledged. [ABSTRACT FROM AUTHOR]

Temperate-zone anguillid eels use both saline (marine or brackish) and fresh waters during their continental phase, but use of fresh waters is paradoxical because on average these fishes grow more rapidly in saline than in fresh waters. Based on data from anguillid eels whose habitat-residency histories had been determined by Sr:Ca otolithometry, superiority of growth rates in saline water is much greater in American eels Anguilla rostrata in north-eastern North America (mean saline:fresh growth rate ratio 2·07) than in European Anguilla anguilla, Japanese Anguilla japonica and shortfinned Anguilla australis eels (range of mean ratios 1·12–1·14). Data from A. rostrata in the Hudson Estuary, U.S.A., and Prince Edward Island, Canada, were used to test adaptive explanations of catadromous migrations. The hypothesis that lower mortality in fresh water offsets faster growth in saline water was not supported because loss (mortality + emigration ) rates did not vary between saline and fresh zones of the Hudson Estuary. Hypotheses that anguillid eels move to fresh water to escape from larger anguillid eels in saline water or to evaluate habitat quality were not supported by size and age distributions. Catadromy in temperate-zone anguillid eels increases the diversity of occupied habitats and therefore lowers fitness variance caused by environmental fluctuations. Catadromy in temperate-zone anguillid eels could be due to natural selection for maximum geometric mean fitness which is sensitive to fitness variance. Temperate-zone catadromy might also be maladaptive, at least in local areas, due to shifts over time in selective pressures or to inability of panmictic genetic systems to adapt to local conditions. [ABSTRACT FROM AUTHOR]

Studies the immediate invasive strategy for the treatment of acute myocardial infarction (MI) early after non-cardiac surgery. Study methods and population; Factors contributing to the delay in the occurrence of symptoms of MI; Treatment options for patients with coronary anatomy unsuitable for angioplasty.

We report the case of a 73-year-old lady who was seen with an infected sinus leaking from the wound of a recently inserted right total hip joint prosthesis. Plain radiographs revealed gas shadows in the region of the wound. An intra-operative sinogram showed the sinus to be coming from a pelvic diverticular abscess and the hip to be an innocent bystander. Our case emphasises the importance of having a clear preoperative plan with relevant investigations before a radical operative procedure is undertaken, to avoid unnecessary risk to a non-infected hip prosthesis. [ABSTRACT FROM AUTHOR]