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Ocean warming and acidification are expected to influence the biology of the ecologically and economically important red king crab, Paralithodes camtschaticus. We investigated transcriptome responses of adult, larval and juvenile red king crab to assess sensitivity to reduced pH and elevated temperature. In adults, gill tissue (but not heart or cuticle) responded to reduced pH by differentially regulating many genes involved in metabolic, membrane and cuticular processes, but not ionic or acid/base regulation. In larval crabs, we found little evidence for a strong transcriptomic response to pH, but did observe large differences in the transcriptomes of newly hatched and one-week old larvae. In juvenile crabs, we found that there was a strong transcriptomic response to temperature across all pH conditions, but that only extreme low pH caused transcriptomic shifts. Most of the genes in juveniles that were differentially expressed were for cuticular and calcification processes. While inferences regarding the specific biological responses associated with changes in gene expression are likely to change as resources for red king crab genomics enabled studies continue to improve (i.e. better assemblies and annotation), our inferences about general sensitivities to temperature and pH across the life stages of red king crab are robust and unlikely to shift. Overall, our data suggest that red king crab are more sensitive to warming than acidification, and that responses to acidification at the transcriptomic level occur at different levels of pH across life stages, with juveniles being less pH sensitive than adults.
People living in poverty are particularly vulnerable to shocks, including those caused by natural disasters such as floods and droughts. This paper analyses household survey data and hydrological riverine flood and drought data for 52 countries to find out whether poor people are disproportionally exposed to floods and droughts, and how this exposure may change in a future climate. We find that poor people are often disproportionally exposed to droughts and floods, particularly in urban areas. This pattern does not change significantly under future climate scenarios, although the absolute number of people potentially exposed to floods or droughts can increase or decrease significantly, depending on the scenario and region. In particular, many countries in Africa show a disproportionally high exposure of poor people to floods and droughts. For these hotspots, implementing risk-sensitive land-use and development policies that protect poor people should be a priority.
Electronic patient records were used to investigate the level of engagement and treatment that patients with very late-onset schizophrenia-like psychosis (VLOSLP) had with mental health services.
Of 131 patients assessed and diagnosed, 63 (48%) were taking antipsychotic treatment at 3 months, 46 (35%) at 6 months and 36 (27%) at 12 months. At discharge from mental health services, 54% of patients had failed to engage with services or became lost to follow-up, 18% had engaged with services but were not taking antipsychotic medication and only 28% were taking treatment.
Results showed that less than half of the patients with VLOSLP were commenced on antipsychotic treatment and less than a third remained on treatment at 1 year or at point of discharge. This highlights the need for services to consider being more assertive in taking potentially effective treatment to this patient group.
Recruitment of adequate numbers of doctors to psychiatry is difficult.
To report on career choice for psychiatry, comparing intending psychiatrists with doctors who chose other clinical careers.
Questionnaire studies of all newly qualified doctors from all UK medical schools in 12 qualification years between 1974 and 2009 (33 974 respondent doctors).
One, three and five years after graduation, 4–5% of doctors specified psychiatry as their first choice of future career. This was largely unchanged across the 35 years. Comparing intending psychiatrists with doctors who chose other careers, factors with a greater influence on psychiatrists' choice included their experience of the subject at medical school, self-appraisal of their own skills, and inclinations before medical school. In a substudy of doctors who initially considered but then did not pursue specialty choices, 72% of those who did not pursue psychiatry gave ‘job content’ as their reason compared with 33% of doctors who considered but did not pursue other specialties. Historically, more women than men have chosen psychiatry, but the gap has closed over the past decade.
Junior doctors' views about psychiatry as a possible career range from high levels of enthusiasm to antipathy, and are more polarised than views about other specialties. Shortening of working hours and improvements to working practices in other hospital-based specialties in the UK may have reduced the relative attractiveness of psychiatry to women doctors. The extent to which views of newly qualified doctors about psychiatry can be modified by medical school education, and by greater exposure to psychiatry during student and early postgraduate years, needs investigation.
Objective: Increased impulsivity has been shown to be a trait feature of adults with bipolar disorder (BD), yet impulsivity has received little study in adolescents with BD. Thus, it is unknown whether it is a trait feature that is present early in the course of the disorder. We tested the hypotheses that self-reported impulsiveness is increased in adolescents with BD, and that it is present during euthymia, supporting impulsiveness as an early trait feature of the disorder.
Methods: Impulsiveness was assessed in 23 adolescents with BD and 23 healthy comparison (HC) adolescents using the self-report measure of impulsivity, the Barratt Impulsiveness Scale (BIS), comprised by attentional, motor and non-planning subscale scores. Effects of subscale scores and associations of scores with mood state and course features were explored.
Results: Total and subscale BIS scores were significantly higher in adolescents with BD than HC adolescents. Total, attentional and motor subscale BIS scores were also significantly higher in the subset of adolescents with BD who were euthymic, compared to HC adolescents. Adolescents with BD with rapid-cycling and chronic mood symptoms had significantly higher total and motor subscale BIS scores than adolescents with BD without these course features.
Conclusion: These results suggest increased self-reported impulsiveness is a trait feature of adolescents with BD. Elevated impulsivity may be especially prominent in adolescents with rapid-cycling and chronic symptoms.
Epidemiological studies have repeatedly found that whole-grain (WG) cereal foods reduce the risk of several lifestyle-related diseases, though consistent clinical outcomes and mechanisms are elusive. To compare the effects of a WG-rich diet with a matched refined-grain (RG) diet on plasma biomarkers and bowel health parameters, seventeen healthy subjects (eleven females and six males) completed an exploratory cross-over study with a 2-week intervention diet based on either WG- or RG-based foods, separated by a washout of at least 5 weeks. Both diets were the same except for the use of WG (150 g/d) or RG foods. Subjects undertook a 4 h postprandial challenge on day 8 of each intervention diet. After 2 weeks, the WG diet tended to decrease plasma total and LDL-cholesterol (both P = 0·09), but did not change plasma HDL-cholesterol, fasting glucose, C-reactive protein or homocysteine compared with the RG diet. Plasma betaine and alkylresorcinol concentrations were elevated after 1 week of the WG diet (P = 0·01 and P < 0·0001, respectively). Clostridium leptum populations in faeces were increased after the WG diet, along with a trend for decreased faecal water pH (P = 0·096) and increased stool frequency (P < 0·0001) compared with the RG diet. A short controlled intervention trial with a variety of commercially available WG-based products tended to improve biomarkers of CVD compared with a RG diet. Changes in faecal microbiota related to increased fibre fermentation and increased plasma betaine concentrations point to both fibre and phytochemical components of WG being important in mediating any potential health effects.
Plant productivity and other ecosystem processes vary widely in their responses to experimental increases in atmospheric carbon dioxide (CO2) concentration. A conceptual framework first suggested by Chapin et al. (1996) was adapted to address the question of why CO2 effects on primary productivity vary so greatly among rangelands and among years for a given ecosystem. The ‘interactive controls’ framework is based on the premise that the influence of elevated CO2 on productivity is governed by a set of internal variables that interact dynamically with ecosystem processes. These interactive controls, which include regional climate, soil resource supply, major functional groups of organisms and disturbance regimes, both regulate CO2 effects on ecosystems and respond to CO2 effects. Changes in interactive controls resulting from CO2 enrichment may feed back to dampen or amplify ecosystem responses to CO2. Most feedbacks from interactive controls will be negative and dampen CO2 effects on ecosystems. Negative feedbacks promote homeostasis in ecosystem processes and reduce the response of plant productivity to CO2. Positive feedbacks on CO2 responses are fewer, but can sustain or even increase benefits of CO2 enrichment for productivity. Positive feedbacks on CO2 responses occur most frequently through changes in plant species and functional group composition. Understanding positive and negative feedbacks on CO2 responses could be one key to predicting consequences of CO2 enrichment for rangeland productivity and other processes.
Heterodontosaurids are poorly understood early ornithischian dinosaurs with extensive geographic and stratigraphic ranges. The group is best known from the Lower Jurassic upper ‘Stormberg Group’ (upper Elliot and Clarens formations) of southern Africa, previously represented by at least three distinct species and ten described specimens. This paper describes four additional heterodontosaurid specimens from southern Africa. A partial skull of a large individual of Heterodontosaurus tucki (NM QR 1788) is approximately 70 longer than that of the type specimen of Heterodontosaurus, and provides new information on allometric changes in mandibular morphology during growth in this taxon. It is the largest known heterodontosaurid cranial specimen, representing an individual approximately 1·75 metres in length, and perhaps 10 kg in body mass. NHMUK R14161 is a partial skull that appears to differ from all other heterodontosaurids on the basis of the proportions of the dentaries, and may represent an unnamed new taxon. Two additional partial skulls (NHMUK RU C68, NHMUK RU69) are referred to cf. Lycorhinus. At least four, and possibly five or more, heterodontosaurid species are present in the upper ‘Stormberg’. This high diversity may have been achieved by dietary niche partitioning, and suggests an adaptive radiation of small-bodied ornithischians following the end Triassic extinctions.
Current ultrasound techniques can accurately determine the chorionicity of twins, but not zygosity. We previously proposed that the zygosity of spontaneously conceived twins can be determined at early ultrasound, where 2 corpora lutea infers dizygosity, and 1 implies monozygosity. Here we did a case series, comparing zygosity predicted using this method with definitive DNA genotyping of twins after birth. We retrospectively identified 14 ultrasound reports of spontaneous twin pregnancies at 6(+0 days) to 13+6 weeks' gestation, where both ovaries were seen and the number of corpora lutea documented. We visited all twin pairs, obtained buccal smears, and determined zygosity by genotyping 9 independent microsatellite markers. All 8 cases where 2 corpora lutea were seen were dizygotic pregnancies. One further case where 3 corpora lutea were seen was also dizygotic. All 3 sets of monozygotic twins had 1 corpus luteum. There were 2 cases incorrectly assigned, where 1 corpus luteum was seen in dizygotic pregnancies. We conclude if 2 corpora lutea are seen at a first trimester ultrasound of spontaneously conceived dichorionic twins, they appear to be almost certainly dizygotic. However, if 1 corpus luteum is seen in dichorionic twins, zygosity cannot be determined with certainty since it is either monozygotic, or dizygotic where a second corpus luteum has been missed.
Industrial logging is expanding rapidly in Central African rainforests. We suggest that logging operations in this region pose an indirect threat to nesting marine turtles, especially the Critically Endangered leatherback turtle Dermochelys coriacea. This occurs because some logs are being lost or abandoned during downriver transport to coastal timber yards; the lost logs float out to sea and then often wash ashore, where they accumulate on beaches used by nesting turtles. We used a light aircraft to survey logs along the entire coastline of Gabon, and also studied the impacts of logs at Pongara Beach, one of the world's most important turtle nesting areas, during the 2002-2003 and 2003-2004 breeding seasons. Nearly 11,000 lost logs were counted along Gabon's beaches, with an estimated commercial value of USD 11.1 million. Logs were unevenly distributed along the coast, reaching a peak density of 247 logs km-1. At Pongara, logs blocked 30.5% of the beach. These logs had a number of negative effects on marine turtles, causing 8-14% of all nesting attempts (n = 2,163) to be aborted or disrupted. Initiatives to remove lost logs and driftwood from critical nesting beaches may be the most effective means to reduce their deleterious impacts on threatened marine turtles.
The cell lineage heterogeneity is an essential component of early morphogenesis and is associated with the maintenance of developmental potential for the embryo. The mammalian embryo has long been considered to exhibit remarkable regulative capacity, presumably reflecting a plasticity in developmental potential to combat different environmental conditions. Cell contact patterns between blastomeres have a major influence on this dynamic state. While compaction and epithelial cell polarisation at the 8-cell stage is mediated by cell adhesion, contact patterns remain effective in steering developmental pathways throughout the cleavage period. The capacity to recavitate and re-form trophectoderm-like outer cells is progressively lost when inner cell masses (ICMs) are isolated from older, more expanded blastocysts which then form predominantly primary endoderm-like structures. The cell contact pattern, either asymmetric or symmetric, maintaining trophectoderm and ICM lineage pathways respectively, acts upstream of signal transduction mechanisms regulating phenotypic status.
The effects of acetic, propionic, butyric and lactic acids (short-chain acids), and of glycerol, on the in vitro dry matter digestibility (IVDMD) of oat hay, and on cellulolysis by a protein extract of rumen fluid were studied. The objective was to gain information on the impact of increasing the concentrations of those compounds in the medium on degradative activities carried out by rumen microorganisms. Short-chain acids were assayed as sodium salts and, for all compounds, the concentrations were 50, 100, 200 and 300 mM. The volatile fatty acids (VFA: acetic, propionic and butyric acids) were tested separately or in two mixtures A and B that contained different proportions of each VFA. The IVDMD was assayed according to a modified Tilley & Terry (1963) technique while cellulolysis was assessed by the hydrolysis of carboxymethylcellulose (CMC) in 1-h incubations at 39 °C. Parallel incubations with NaCl were utilized as controls for ionic strength and osmolarity changes in the incubation medium. Increases of 100–300 mM of short-chain acids decreased IVDMD between 7 and 39%. The inhibitions produced by increases of 200 and 300 mM of acetic acid were smaller than those caused by the same concentrations of either butyric or lactic acids. Increases of 100, 200 and 300 mM of glycerol reduced by 8–15% the IVDMD, and the inhibitions produced by increments of 200 and 300 mM of this compound were smaller than the ones elicited by the short-chain acids, with the exception of 200 mM of acetic acid that did not differ. The IVDMD was inhibited by NaCl only when concentrations were increased by 200 (12%) and 300 mM (26%). The degradation of CMC was reduced by 7–20% by 200 and 300 mM increases of the short-chain acids or glycerol, the exception being lactic acid that had no effect. One hundred mM increases of acetic and butyric acids inhibited the CMC degradation by 7 and 9%, respectively, whereas only butyric acid was inhibitory (7%) at 50 mM. Greater concentration increases of both VFA mixtures A and B than of the individual VFA were necessary to inhibit the hydrolysis of CMC. Cellulolytic activity was decreased 6 and 9% by increases of 200 and 300 mM of NaCl, respectively, and these drops of activity were smaller than those obtained with increases in any of the other compounds. Since osmolarity and/or ionic strength changes in the medium cannot completely account for the observed inhibitions of IVDMD and cellulolysis, it is suggested that glycerol and the anions of short-chain acids produce changes in the reaction media polarity that contribute to the inhibitory effects observed. Alterations in the media could also bring about conformational changes in the degradative enzymes leading to reduced rates of reaction and subsequent decreases in IVDMD and cellulolysis. Since most of the effects were observed with concentration increases that were larger than the physiological concentrations in the rumen, it is suggested that the compounds tested have little impact in vivo on the ruminal degradative activities that were evaluated.
Synthesis, mechanical testing, and modeling have been performed for a carbon nanotube material in which the nanotubes are functionalized with variable stiffness tethers (VST) capable of cross-linking the nanotubes. Tests using nanoindentation indicated a six-fold enhancement in the storage modulus when comparing the base material (the cross-linking agent with no nanotubes) to the composite (functionalized nanotube material) that contained 5.3 wt% of nanotubes. To understand how crosslinking the nanotubes may further alter the stiffness, a model of the system was constructed using nanotubes crosslinked with the VST. The model predicted that for a composite with 5 wt% nanotubes at random orientations, crosslinked with the VST, the bulk Young's modulus was reduced to 30% that of the non-crosslinked equivalent.
A revised generic synopsis of sub-Saharan Hyacinthaceae is presented, based on a molecular phylogenetic analysis of the family. Generic rank is accorded only to reciprocally monophyletic clades that can be distinguished by recognizable morphological discontinuities, thereby permitting an appropriate generic assignment of species not included in the analysis. Three subfamilies are recognized within the region. Subfamily Ornithogaloideae, characterized by flattened or angular seeds with tightly adhering testa, is considered to include the single genus Ornithogalum, which is expanded to include the genera Albuca, Dipcadi, Galtonia, Neopatersonia and Pseudogaltonia. Recognizing any of these segregates at generic level renders the genus Ornithogalum polyphyletic, while subdivision of Ornithogalum into smaller, morphologically distinguishable segregates in order to preserve the monophyly of each is not possible. Subfamily Urgineoideae, characterized by flattened or winged seeds with brittle, loosely adhering testa, comprises the two mainland African genera Bowiea and Drimia. The latter is well circumscribed by its deciduous, short-lived perianth and includes the previously recognized genera Litanthus, Rhadamanthus, Schizobasis and Tenicroa. The monotypic Madagascan Igidia is provisionally included in the subfamily as a third genus on the basis of its seeds, pending molecular confirmation of its relationships. Subfamily Hyacinthoideae resolves into three clades, distinguished as tribes Hyacintheae (strictly northern hemisphere and not treated further), Massonieae and Pseudoprospereae tribus nov. Full descriptions and a key to their identification are provided for all genera. New combinations reflecting the generic circumscriptions adopted here are made for most African and all Indian and Madagascan species.
Nanophase Technologies Corporation (NTC) employs a new physical vapor synthesis technique to manufacture ceria-based mixed rare earth oxide nanomaterials. The mixed rare earth oxide nanoparticles are nonporous, dense, discrete crystals. The compositions are solid solutions that remain thermally stable to above 1050°C.
Ceria is an active oxygen storage material. Doping ceria with other rare earth metals enhances the thermal stability of nanocrystalline particle size and increases the oxygen storage capacity (OSC). The mean particle size and OSC of ceria-based mixed rare earth oxides are presented as a function of particle composition, morphology, and thermal history.
These materials are commercially available and are being engineered for several applications including oxygen storage catalysts and polishing materials.