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The rotifer Epiphanes brachionus spinosa occurs in shallow temporary waters with hydroperiods up to several months in the Chihuahuan Desert (U.S.A. and Mexico). Clonal populations from one such habitat were initiated from stem females hatched from fertilised resting eggs in flooded dried sediment, and cultured with the alga Cryptomonas erosa at 19°C in a photoperiod (L:D 16:8). Experiments show that the rotifer has: (1) a morphological response to the predatory rotifer Asplanchna, with which it can co‐occur; and (2) an early and constant propensity for sex and resting‐egg production during population development.Stem females, and females from later generations, have two posterior spines. Measurements of live juveniles and adults indicate that spine length increases isometrically during postnatal growth.Presence of live Asplanchna brightwellii, or its kairomone in Asplanchna‐conditioned medium, significantly increase spine length. In one clone, spine lengths of juvenile Epiphanes from cultures with or without live Asplanchna were, respectively, c. 40 and c. 27 μm. In that clone, spine lengths of adult Epiphanes in cultures with or without Asplanchna kairomone were, respectively, c. 54 and c. 37 μm. In another clone, these spine lengths were, respectively, c. 44 and c. 36 μm. Asplanchna‐induced spine elongation may act as a mechanical defence against capture and ingestion by the predator.Sexual reproduction in E. brachionus spinosa populations is initiated soon after populations develop from stem females and then continues at a rate allowing both population growth by female parthenogenesis and production of resting eggs. Resting eggs hatched after 6–12 days at 19°C. Stem females were amictic (producing daughters parthenogenetically) but produced some daughters that were mictic (producing haploid males parthenogenetically or fertilised resting eggs). In subsequent generations tested 2–7 weeks after hatching of stem females, amictic females from three clonal populations produced similar proportions of mictic daughters (mean c. 0.25) when cultured singly in large volumes (15 and 40 ml) or a small one (1.5 ml).Mictic‐female production is probably automatic and controlled by an endogenous mechanism, rather than specifically induced by crowding or some other environmental factor. Early and continuous sexual reproduction assures production of resting eggs throughout short and unpredictable hydroperiods. [ABSTRACT FROM AUTHOR]

Excel simulation models have become increasingly common in the economics classroom, as their ability to combine numerical and graphical information has proved a useful support to traditional teaching methods. Recent efforts have tended to embed the solution within the Excel sheet, avoiding the need to use the Solver add‐in and allowing changes in the exogenous characteristics of the model to be instantly reflected in the numerical solutions and any associated geometry. While this is quite simple in small‐scale linear models, it is less straightforward in larger nonlinear models such as those that dominate the theory of international trade. We discuss various methods that can be used in building Excel simulations when it is not possible to solve the underlying model explicitly. We illustrate the ideas and describe our experiences along with a new simulation of the specific factors model. [ABSTRACT FROM AUTHOR]

In a differentiated duopoly model of trade and FDI featuring both horizontal and vertical product differentiation, we examine whether globalization and trade policy measures can generate welfare gains by leading firms to change their mode of competition. We show that when a high‐quality foreign variety is manufactured under large frictions due to upstream monopoly power, a foreign firm can become a Bertrand competitor against a Cournot local rival in equilibrium, especially when the relative product quality of the foreign variety is sufficiently high and trade costs are sufficiently low (implying higher input price distortions due to double marginalization). Our results suggest that such strategic asymmetry is welfare improving and that the availability of FDI as an alternative to trade can make welfare‐enhancing strategic asymmetry even more likely, especially when both input trade costs and fixed investment costs are sufficiently low and trade costs in final goods are sufficiently large. [ABSTRACT FROM AUTHOR]

Rapid automation in manufacturing has raised pressing questions in public and policy discourse regarding the effects of labor‐eliminating technical progress in an industry. We address the implications of a labor‐eliminating technology adopted in manufacturing for factor price changes, the skilled–unskilled wage gap, and for trade policies intended to protect workers. Using an otherwise traditional multisector general equilibrium model, we derive the conditions under which a labor‐eliminating technology will be adopted in manufacturing, and show that such a technical change will increase the rate of return on capital, and decrease both skilled and unskilled labor wages. We derive conditions under which wage inequality increases, and most importantly, show that implementing protectionist trade policies in the industry experiencing labor‐eliminating technical progress will, paradoxically, hurt the workers that the policy is meant to protect. [ABSTRACT FROM AUTHOR]

We scrutinize international trade arising from oligopolistic rivalry (reciprocal dumping) in a model where the goods are horizontally differentiated and where otherwise symmetric firms located in different regions adopt asymmetric strategies—one competing in prices and the other competing in quantities. Unidirectional and intra‐industry trade appear endogenously in our framework. We show that as trade costs decline the equilibrium outcome will transition from autarky through a region of unidirectional trade, before intra‐industry trade ultimately arises. In the unidirectional trade region, potential market entry by the rival has an impact on firm behavior even though the rival is not exporting. The implications of product differentiation and changing trade costs for trade volumes and for the gains from trade are asymmetric in general. Welfare may rise monotonically as trade costs fall for one of the economies, but will necessarily fall initially relative to autarky for the other. [ABSTRACT FROM AUTHOR]

Autopsy findings in intravenous drug addicts are quite variable and may involve a number of organ systems. Reports of the macroscopic identification at autopsy of components of tablets that have been crushed and injected are, however, exceedingly rare. The case of 34‐year‐old man who died of zolpidem toxicity on a background of pulmonary hypertension attributed to intravenous injections of crushed tablets is described. A very unusual finding was very fine white stippling on the cut surfaces of both the liver and spleen which was shown on energy‐dispersive x‐ray spectroscopy (EDS) to be titanium dioxide most likely from the coating of the zolpidem tablets. This case is significant in demonstrating titanium dioxide accumulation within organs at both macroscopic and microscopic levels, with confirmation of exposure by EDS analysis. The clinical significance of exposure to such high levels of titanium dioxide is unclear. [ABSTRACT FROM AUTHOR]

Developing countries face significant challenges arising from automation. While the trade theory literature has tended to focus on factor‐neutral and factor‐augmenting technical change, automation processes suggest another form of technical change is relevant: factor‐eliminating. We explore the impact of a labor‐eliminating technical change in the context of a small developing economy. Unlike labor‐augmenting technical changes, labor‐eliminating technical changes are not necessarily cost‐reducing, and thus will not necessarily be adopted. A manufacturing wage held artificially higher than at the market‐clearing level, as in the Harris–Todaro framework, increases the incentive to automate. We establish the conditions under which firms will adopt a labor‐eliminating technology, and describe the resulting changes in equilibrium outcomes. Under plausible circumstances, automation can actually lower output, and may raise both the rate and level of unemployment. Immiserizing growth becomes a possibility, and can be tied directly to the underlying wage distortion. [ABSTRACT FROM AUTHOR]

A review of research on life‐cycle events in field and laboratory populations of monogonont rotifers shows that there is great variation at multiple levels: (1) degree of sexual dimorphism; (2) occurrence and timing of sex; (3) propensity for sex during sexual periods; (4) factors controlling initiation of sex; and (5) timing and extent of emergence from diapause. There is no regular pattern where: (1) fertilised resting eggs hatch to start the growing season; (2) populations develop via female parthenogenesis during favourable conditions; and then (3) bisexual reproduction with resting‐egg production occurs during later, unfavourable conditions.Sexual reproduction in natural populations can occur throughout much of the growing season, be restricted to some period(s) during the growing season, or be completely absent. During sexual reproduction in both natural and laboratory populations, only some fraction of females produces males or resting eggs. This bet‐hedging strategy can prevent a population crash and permits future population growth via female parthenogenesis. Selection against sexual reproduction, and rapid loss of sex, can occur.Laboratory experiments with pond‐dwelling species have identified specific environmental factors that induce sex in different species: (1) increasing population density; (2) dietary tocopherol (vitamin E) and (3) long photoperiods. These factors generally are associated with favourable conditions for population growth and production of energy‐rich resting eggs: (1) large population size; (2) high probability of contacts between males and fertilisable females; and (3) nutritious diets. Endogenous factors can inhibit responses to these environmental inducers, and thus favour female parthenogenesis.The timing of resting‐egg hatching depends on: (1) occurrence of specific environmental conditions; (2) the minimum duration of obligate diapause; and (3) the genotype and physiology of females producing resting eggs. Hatching may occur shortly after oviposition, after a long diapause before or at the start of a new growing season, or throughout the growing season. Hatching can be massive and contribute substantially to population growth and genetic diversity.Areas for future research include: (1) determining the timing and extent of sex and resting‐egg hatching in more natural populations, especially those that are marine, benthic, sessile, and interstitial; and (2) identifying environmental and physiological factors controlling these events. [ABSTRACT FROM AUTHOR]

Whole exome sequencing and copy‐number variant analysis was performed on a family with three brothers diagnosed with autism. Each of the siblings shares an alteration in the nuclear receptor subfamily 3 group C member 2 (NR3C2) gene that is predicted to result in a stop‐gain mutation (p.Q919X) in the mineralocorticoid receptor (MR) protein. This variant was maternally inherited and provides further evidence for a connection between the NR3C2 and autism. Interestingly, the NR3C2 gene encodes the MR protein, a steroid hormone‐regulated transcription factor that acts in the hypothalamic–pituitary–adrenal axis and has been connected to stress and anxiety, both of which are features often seen in individuals with autism. Autism Res 2020, 13: 523–531. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. Lay Summary: Given the complexity of the genetics underlying autism, each gene contributes to risk in a relatively small number of individuals, typically less than 1% of all autism cases. Whole exome sequencing of three brothers with autism identified a rare variant in the nuclear receptor subfamily 3 group C member 2 gene that is predicted to strongly interfere with its normal function. This gene encodes the mineralocorticoid receptor protein, which plays a role in how the body responds to stress and anxiety, features that are often elevated in people diagnosed with autism. This study adds further support to the relevance of this gene as a risk factor for autism. [ABSTRACT FROM AUTHOR]

Induced morphological defenses commonly develop in some loricate rotifers as greatly increased spine development and in many species of the cladoceran genus Daphnia as an alteration in the shape and size of its head, producing helmets, crests, and neck spines. This restructuring of the shape of these animals during development, which reduces their vulnerability to a variety of planktonic predators, involves a series of developmental challenges and potential evolutionary constraints for each specific type of defense. In this review, we examine these challenges and the divergent developmental patterns that evolved in rotifers and Daphnia in response to the particular forms of predation pressure they face in their lake and pond environments. These patterns involve differences in the sensitivity of various developmental stages to predator kairomones, the timing of when the defense is present during postembryonic development, the ability to reverse the induced defense if the predator disappears from the community, and the effect of water temperature on the induction process. The type of developmental pattern associated with each induced defense appears to have been shaped by natural selection to effectively protect the animal, at minimal cost, from the specific kind of predation pressure to which it is commonly subjected. [ABSTRACT FROM AUTHOR]

The article discusses lessons from the computable general equilibrium (CGE) simulation modeling of the economic impact of the Trans-Pacific Partnership (TPP). Topics tackled are the trade liberalization component of the TPP compared with the proposed Regional Comprehensive Economic Partnership (RCEP) and the Free Trade Area of the Asia-Pacific (FTAAP), implications of excluding products from the TPP agreement, and feasibility of expanding the TPP.

ABSTRACT Pronounced non-genetic polymorphisms, or polyphenisms, occur in some monogonont rotifers reproducing by diploid, female parthenogenesis. In many brachionids, there is great variation in spine length. In trimorphic species of Asplanchna, females can vary in size and shape, from a small saccate morph to giant cruciform and campanulate morphs. In species that also reproduce sexually, diploid eggs can develop into two types of females. Amictic females produce diploid eggs that develop parthenogenetically into females; mictic females produce haploid eggs that develop parthenogenetically into males or, if fertilized, into resting eggs. In a species of Synchaeta, amictic females produce diploid eggs that can be either thin-shelled and subitaneous or thicker-shelled and diapausing. In all cases, morph determination occurs during the oogenesis or embryological development of diploid eggs in the maternal body cavity. For the first time, these polymorphisms are reviewed together and compared regarding a number of features associated with transitions from default to induced morphs: ( i) type of variation (morphological, physiological, or both; continuous or discrete); ( ii) inducing signal (environmental, endogenous, or both); ( iii) universality of response to that signal (all or only some individuals); ( iv) fitness cost; ( v) reversibility; and ( vi) ecological significance. Most of the polymorphisms fall into two major categories regarding these features. Transitions suitable for predictable environments involve: universal responses to environmental signals; continuous morphological variation; low reproductive cost; rapid reversibility; and adaptations for defence, hydrodynamics or prey ingestion. Transitions suitable for unpredictable environments are bet-hedging strategies and usually involve: partial (stochastic) responses to environmental or endogenous signals; discontinuous physiological variation; initiation of diapause, and thus high reproductive cost and slow reversibility. Two cases of morphological variation also involve the simultaneous production of different morphs and likely are adaptations for an uncertain future: continuous spine-length variation due to maternal age in Brachionus calyciflorus, and production of discrete cruciform and campanulate females in Asplanchna spp. [ABSTRACT FROM AUTHOR]

Two cases of occult pseudoaneurysms of the sinus of Valsalva (SoV) are reported to demonstrate different etiologies and lethal mechanisms. A previously well 9-month-old boy who suffered an unexpected fatal cardiorespiratory arrest was found at autopsy to have a ruptured pseudoaneurysm of the left SoV resulting in lethal hemopericardium. A 13.5-month-old boy died soon after presenting with a 24-h history of poor feeding and reduced urine output. At autopsy, destruction of the noncoronary cusp of the aortic valve by bacterial endocarditis was found with extension of the inflammation into a pseudoaneurysm of the SoV with surrounding abscess formation involving the atrioventricular node. Death was most likely due to an arrhythmia. Pseudoaneurysms of the SoV are exceedingly rare but may result in sudden/unexpected death in infancy and early childhood from rupture or involvement of the conduction system or myocardium. Detailed cardiac examination is essential in all unexpected deaths in early life. [ABSTRACT FROM AUTHOR]

A 32‐year‐old woman collapsed following an intravenous injection of material that included crushed pharmaceutical tablets. Resuscitation was attempted but was unsuccessful. She had an extensive past medical history of complications resulting from intravenous drug use. Death was due to mixed drug toxicity. The major findings at autopsy included a 10 mm deep skin sinus over the right femoral vein that was used as an injection site. Polarizable foreign material was present at the injection site and also within the lungs with a granulomatous reaction. Of note, a probe‐patent foramen ovale had permitted paradoxical embolization of this material into the systemic circulation with lodgement within the liver, portal lymph nodes, myocardium, spleen, kidneys, and pancreas. This case highlights the importance of checking for any intracardiac shunts, which may be quite small, and systemic dissemination of foreign material to multiple organs in intravenous drug users who present for medicolegal assessment. [ABSTRACT FROM AUTHOR]

Background: Essential tremor is a neurological condition characterized by tremor during voluntary movement. To date, 3 loci linked to familial essential tremor have been identified.Methods: We examined 48 essential tremor patients in 5 large essential tremor pedigrees in our data set for genetic linkage using an Affymetrix Axiom array. Linkage analysis was performed using an affecteds-only dominant model in SIMWALK2. To incorporate all genotype information, GERMLINE was used to identify genome segments shared identical-by-descent in pairs of affecteds. Exome sequencing was performed in pedigrees showing evidence of linkage.Results: For one family, chromosomes 5 and 18 showed genome-wide significant linkage to essential tremor. Shared segment analysis excluded the 18p11 candidate region and reduced the 5q35 region by 1 megabase. Exome sequencing did not identify a potential causative variant in this region.Conclusion: A locus on chromosome 5 is linked to essential tremor. Further research is needed to identify a causative variant. © 2016 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background and objective: Children from culturally and linguistically diverse (CALD) backgrounds are at risk of having developmental problems go undetected prior to starting school, and missing out on early intervention. Our aim was to explore the family and service characteristics, beliefs and experiences that influence the journey of families from CALD backgrounds in accessing developmental surveillance (DS) and early intervention services in south‐eastern Sydney, Australia. Design, setting and participants: This qualitative study used in‐depth interviews conducted with 13 parents from CALD backgrounds and 27 health and early childhood professionals in Sydney. The Andersen Behavioural Model of Health Service Use (BM) was the underlying theoretical framework for thematic analysis. Results and discussion: Family and service knowledge about early childhood development (ECD), community attitudes, social isolation and English language proficiency were dominant themes that impacted on the probability of families accessing services in the first place. Those that impeded or facilitated access were resources, extended family and social support, information availability, competing needs, complex service pathways and community engagement. There were variable practices of early detection through DS. Children from CALD backgrounds with developmental problems were perceived to miss out on DS and early intervention despite language delay being a key issue identified by participants. Conclusion: This study highlights the importance of increased community and family awareness and professional training in ECD; better coordination of health and early childhood services, with simpler referral pathways to early intervention to prevent children from CALD backgrounds ‘slipping through the net’. [ABSTRACT FROM AUTHOR]

We consider a general equilibrium model of a developing economy (the South) that opens to trade with a developed economy (the North). The southern economy is characterized by open urban unemployment and rural-urban migration, a competitive agricultural sector and a monopolistically competitive manufacturing sector. Hence, there is potential for both inter- and intra-industry trade to arise on liberalization, in addition to distortionary effects of duality. Southern comparative advantage in agriculture may arise from the labor market distortion and the basis for intra-industry trade is love for variety. We characterize various configurations of the trade pattern, and the resulting welfare consequences of opening to trade in this context. We illustrate a new mechanism under which in some circumstances it may be possible for trade liberalization to lower economic welfare in the South. [ABSTRACT FROM AUTHOR]

Abstract: A prospective study was undertaken at Forensic Science SA over a 15‐year period from July 2002 to June 2017 for all cases of adult (>18 years) suicidal hangings with decapitation. A total of 1446 cases of suicidal hangings were identified from a general population of approximately 1.5 million (1206 males—age range 18–97 years, average 42.6; and 240 females—age range 18–96 years, average 40.1). Only three cases of decapitation were found, all from long‐drop hangings; these consisted of three males (ages 32–55 years; average 45 years). Spinal transections had occurred between the first and second, second and third, and third and fourth cervical vertebrae, respectively. In this study, the number of suicidal hangings with decapitation represented only 0.2% of the total number of hangings. These events are therefore extremely rare, most likely due to most suicidal hangings occurring from relatively low levels in a domestic environment. [ABSTRACT FROM AUTHOR]

Abstract: A 19‐year‐old woman with insulin‐dependent diabetes mellitus was found dead in bed having allegedly recently taken ecstasy and consumed alcohol. At autopsy, there were microhemorrhages in the brain with subnuclear vacuolization and Armanni–Ebstein changes in renal tubules. Biochemical analyses confirmed diabetic ketoacidosis (vitreous glucose—46.5 mmol/L; β‐OH butyrate—13.86 mmol/L.). Toxicological analyses of blood showed a low level of 3,4‐methylenedioxy‐methamphetamine (MDMA) (0.01 mg/L), with acetone but no alcohol or other common drugs. Death was attributed to diabetic ketoacidosis most likely provoked by mixed MDMA/alcohol ingestion. Although the use of illicit drugs by young individuals with diabetes mellitus is being increasingly recognized, it has been noted that there is minimal information about the relationship between drug use and acute diabetic complications. Toxicological screening of cases of lethal diabetic ketoacidosis in the young may clarify lethal mechanisms in individual cases and also help to determine the extent of this problem. [ABSTRACT FROM AUTHOR]

Using a general equilibrium model of a developing narcotics-producing and -exporting economy, we analyze the economic effects of policies designed to restrict the production and trade of narcotics: foreign aid tied to anti-narcotics law enforcement activities, demand reduction policies, and alternative development policies. We characterize the problem as one of serious factor market distortions introduced by illicit production and enforcement. While aid to enforcement generally reduces the production and export of narcotics, it is less effective for economies with market power, and under plausible conditions may raise narcotics output and have negative welfare implications for the recipient. ( JEL F1) [ABSTRACT FROM AUTHOR]

Three cases of pharmacobezoars are reported to demonstrate typical autopsy findings and potential lethal mechanisms: (i) A 32-year-old woman died following an overdose of prescription medications. A gelatinous pharmacobezoar was found forming a cast of her bronchial tree. (ii) A 24-year-old woman also died following an overdose of prescription medications. At autopsy, two pharmacobezoars were present, one within the larynx and another occluding the right main bronchus. Deaths in both cases were attributed to airway occlusion by pharmacobezoars complicating mixed drug toxicity. (iii) A 79-year-old man was found dead in a car. Death was attributed to the combined effects of carbon monoxide and drug toxicity with a large pharmacobezoar lodged within the esophagus. Pharmacobezoars are specific types of bezoars that occur when pharmaceutical materials, such as tablets, suspensions, and/or drug delivery devices, aggregate and contribute to death by occluding airways with tenacious material or by eluting drugs. [ABSTRACT FROM AUTHOR]

The Illinois Basin - Decatur Project (IBDP) is a carbon capture and storage (CCS) project that is located at the Archer Daniels Midland (ADM) Company's corn processing plant in Decatur, Illinois. The IBDP has an extensive seismic program that was designed to meet site characterization and monitoring objectives that includes two-dimensional (2D) and three-dimensional (3D) surface seismic data, time-lapse 3D vertical seismic profiles (VSPs), and microseismic monitoring. As little deep subsurface data was available within a 20-mile (32-km) radius of site, the surface seismic surveys have been important to the site characterization objectives for the project. Through seismic inversion analysis, rock properties such as density, porosity, and rock lithology were derived from the surface seismic data and incorporated into the geologic and geomechanical models for the project. Time-lapse 3D VSPs are acquired with a permanent geophone array in Geophysical Monitoring Well #1 (GM1). Carbon dioxide (CO2) injection commenced in November 2012, and the first monitor survey was acquired in February 2012 after approximately 70 000 tonnes of CO2 had been injected. While this is a small volume of CO2 to detect seismically, anomalies were identified that may be suggestive of CO2 movement in the Mt Simon Sandstone at the depth of injection. Microseismic activity has been monitored using the geophone array in GM1 and two deep geophones installed in the Injection well (CCS1). A comparison of the different operation parameters with microseismic activity shows a correlation between microseismicity and pressure changes in the formation. [ABSTRACT FROM AUTHOR]

A four-year-old previously well boy collapsed unexpectedly and was taken immediately to hospital, where he developed seizures and cardiogenic shock with lethal, rapidly progressing multi-organ failure. At autopsy, the height was >90th percentile and there were indications of early virilization. Internally, a friable tumor of the left adrenal gland was identified that had invaded the left renal vein and inferior vena cava. Histology revealed typical features of an adrenocortical carcinoma with aggregated trabeculae of cells containing abundant eosinophilic cytoplasm and large pleomorphic nuclei. There was strong positive cytoplasmic staining for inhibin; mitochondria were shown on electron microscopy to contain prominent electron-dense granules. Death was due to massive pulmonary tumor embolism. Although adrenocortical carcinomas are very rare and are more commonly found in adults, the current case demonstrates that they may also occur in childhood and be responsible for unexpected death by the very unusual mechanism of tumor embolism. [ABSTRACT FROM AUTHOR]

Abstract: Background: The Arg406Trp (R406W) missense mutation in the microtubule-associated protein-tau gene (MAPT) is a known cause of early-onset dementia. Various dementia phenotypes have been described, including frontotemporal dementia (FTD), FTD with parkinsonism, and early-onset Alzheimer disease (EOAD)-like presentations. Methods: Using whole-exome capture with subsequent sequencing, we identified the R406W mutation in a family with multiple individuals with clinically diagnosed EOAD, in a pattern suggesting autosomal dominant inheritance. We reevaluated all available family members clinically. Results: Each of the affected individuals had a course meeting clinical criteria for EOAD. Two distinct disease trajectories were apparent: one rapidly progressive, and the other long and gradual. Four of five affected individuals also manifested parkinsonian symptoms. FTD features were not prominent and, when present, appeared only late in the course of dementia. Conclusions: The MAPT R406W mutation is associated with EOAD-like symptoms and parkinsonism without FTD, as well as distinct cognitive courses. [Copyright &y& Elsevier]

In the context of a simple model of strategic offshoring, we investigate the reasons why firms may simultaneously source fragments domestically and internationally. We explore the impacts of offshoring on the production pattern of finished goods, tradable fragment prices, and welfare in a partial equilibrium context. The policy implications of attempts to restrict offshoring are also considered. The analysis shows that an offshoring equilibrium may exist in the absence of comparative advantage in fragments, that offshoring is welfare improving if the costs are sufficiently small, and that attempts (by both countries) to prevent offshoring may paradoxically lower both fragment use and price. [ABSTRACT FROM AUTHOR]

Brachionus calyciflorus typically develops long, defensive spines only in response to a kairomone from the predatory rotifer, Asplanchna. However, in the absence of any environmental induction, females of some clones produce daughters with increasingly long spines as they age; late-born individuals can have posterolateral spines as long as those induced by Asplanchna: up to 50% or more of body length. Here, we construct a model using data from life-table and predator-prey experiments to assess how this maternal-age effect can influence the distribution of spine lengths in reproducing populations and provide defense against Asplanchna prédation. When Asplanchna is absent, the frequency of individuals with late birth orders rapidly becomes extremely low; thus, any cost associated with the production of long-spined individuals is minimal. When Asplanchna is present at densities too low for spine induction, and preys selectively on individuals with no or short posterolateral spines, the frequency of long-spined individuals rapidly increases until a stable birth-order structure is reached. As a result, mortality from Asplanchna prédation is greatly reduced. The pronounced and novel birth-order effect in this rotifer appears to be an effective bet-hedging strategy to limit prédation by Asplanchna when its kairomone induces no or less than maximal spine development. [ABSTRACT FROM AUTHOR]

We set out to determine whether expansions in the C9ORF72 repeat found in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) families are associated with Parkinson disease (PD). We determined the repeat size in a total of 889 clinically ascertained patients (including PD and essential tremor plus Parkinsonism (ETP)) and 1144 controls using a repeat-primed PCR assay. We found that large C9ORF72 repeat expansions (>30 repeats) were not contributing to PD risk. However, PD and ETP cases had a significant increase in intermediate (>20 to 30+) repeat copies compared to controls. Overall, 14 cases (13 PD, 1 ETP) and three controls had >20 repeat copies (Fisher's exact test p = 0.002). Further, seven cases and no controls had >23 repeat copies (p = 0.003). Our results suggest that intermediate copy numbers of the C9ORF72 repeat contribute to risk for PD and ETP. This also suggests that PD, ALS and FTD share some pathophysiological mechanisms of disease. Further studies are needed to elucidate the contribution of the C9ORF72 repeat in the overall PD population and to determine whether other common genetic risk factors exist between these neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Despite the increasing speculation that oxidative stress and abnormal energy metabolism may play a role in Autism Spectrum Disorders (ASD), and the observation that patients with mitochondrial defects have symptoms consistent with ASD, there are no comprehensive published studies examining the role of mitochondrial variation in autism. Therefore, we have sought to comprehensively examine the role of mitochondrial DNA (mtDNA) variation with regard to ASD risk, employing a multi-phase approach. In phase 1 of our experiment, we examined 132 mtDNA single-nucleotide polymorphisms (SNPs) genotyped as part of our genome-wide association studies of ASD. In phase 2 we genotyped the major European mitochondrial haplogroup-defining variants within an expanded set of autism probands and controls. Finally in phase 3, we resequenced the entire mtDNA in a subset of our Caucasian samples (∼400 proband-father pairs). In each phase we tested whether mitochondrial variation showed evidence of association to ASD. Despite a thorough interrogation of mtDNA variation, we found no evidence to suggest a major role for mtDNA variation in ASD susceptibility. Accordingly, while there may be attractive biological hints suggesting the role of mitochondria in ASD our data indicate that mtDNA variation is not a major contributing factor to the development of ASD. [ABSTRACT FROM AUTHOR]

The methyl- CpG-binding domain ( MBD) gene family was first linked to autism over a decade ago when Rett syndrome, which falls under the umbrella of autism spectrum disorders ( ASDs), was revealed to be predominantly caused by MECP2 mutations. Since that time, MECP2 alterations have been recognized in idiopathic ASD patients by us and others. Individuals with deletions across the MBD5 gene also present with ASDs, impaired speech, intellectual difficulties, repetitive behaviors, and epilepsy. These findings suggest that further investigations of the MBD gene family may reveal additional associations related to autism. We now describe the first study evaluating individuals with ASD for rare variants in four autosomal MBD family members, MBD5, MBD6, SETDB1, and SETDB2, and expand our initial screening in the MECP2 gene. Each gene was sequenced over all coding exons and evaluated for copy number variations in 287 patients with ASD and an equal number of ethnically matched control individuals. We identified 186 alterations through sequencing, approximately half of which were novel (96 variants, 51.6%). We identified 17 ASD specific, nonsynonymous variants, four of which were concordant in multiplex families: MBD5 Tyr1269Cys, MBD6 Arg883Trp, MECP2 Thr240Ser, and SETDB1 Pro1067del. Furthermore, a complex duplication spanning of the MECP2 gene was identified in two brothers who presented with developmental delay and intellectual disability. From our studies, we provide the first examples of autistic patients carrying potentially detrimental alterations in MBD6 and SETDB1, thereby demonstrating that the MBD gene family potentially plays a significant role in rare and private genetic causes of autism. Autism Res 2012, 5: 385-397. © 2012 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

This study investigates two different effects of an ostracod on a rotifer. The rotifer Keratella tropica and the ostracod Cypris pubera were cultured on the alga Cryptomonas erosa. Adult ostracods (2.2 mm body length) significantly reduced the population growth rate (r day-1) of K. tropica from 0.42 to 0.13. Individuals of this size ingested live rotifers and produced fecal pellets with rotifer loricas. Smaller ostracods (both 0.59 and 1.61 mm body lengths) did not affect K. tropica 's population growth rate. Surprisingly, C. pubera significantly inhibited spine development in K. tropica. Rotifers cultured with juvenile, non-predatory ostracods had similar lorica lengths but right and left posterior spines that were 10 and 30% shorter, respectively. The spine reduction induced by the ostracod kairomone is in striking contrast to the spine elongation induced in this rotifer by kairomones from copepods, cladocerans and Asplanchna. In shallow ecosystems, large ostracods that swim in the plankton may be important predators of rotifers. In addition, the presence of ostracods in plankton communities may be one of many factors affecting rotifer spine development. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

To identify novel late-onset Alzheimer disease (LOAD) risk genes, we have analysed Amish populations of Ohio and Indiana. We performed genome-wide SNP linkage and association studies on 798 individuals (109 with LOAD). We tested association using the Modified Quasi-Likelihood Score test and also performed two-point and multipoint linkage analyses. We found that LOAD was significantly associated with APOE ( P= 9.0 × 10-6) in all our ascertainment regions except for the Adams County, Indiana, community ( P= 0.55). Genome-wide, the most strongly associated SNP was rs12361953 ( P= 7.92 × 10-7). A very strong, genome-wide significant multipoint peak [recessive heterogeneity multipoint LOD (HLOD) = 6.14, dominant HLOD = 6.05] was detected on 2p12. Three additional loci with multipoint HLOD scores >3 were detected on 3q26, 9q31 and 18p11. Converging linkage and association results, the most significantly associated SNP under the 2p12 peak was at rs2974151 ( P= 1.29 × 10-4). This SNP is located in CTNNA2, which encodes catenin alpha 2, a neuronal-specific catenin known to have function in the developing brain. These results identify CTNNA2 as a novel candidate LOAD gene, and implicate three other regions of the genome as novel LOAD loci. These results underscore the utility of using family-based linkage and association analyses in isolated populations to identify novel loci for traits with complex genetic architecture. [ABSTRACT FROM AUTHOR]

BACKGROUND Neural tube defects (NTDs) are common human birth defects with a complex etiology. To develop a comprehensive knowledge of the genes expressed during normal neurulation, we established transcriptomes from human neural tube fragments during and after neurulation using long Serial Analysis of Gene Expression (long-SAGE). METHODS Rostral and caudal neural tubes were dissected from normal human embryos aged between 26 and 32 days of gestation. Tissues from the same region and Carnegie stage were pooled (n ≥ 4) and total RNA extracted to construct four long-SAGE libraries. Tags were mapped using the UniGene Homo sapiens 17 bp tag-to-gene best mapping set. Differentially expressed genes were identified by chi-square or Fisher's exact test, and validation was performed for a subset of those transcripts using in situ hybridization. In silico analyses were performed with BinGO and EXPANDER. RESULTS We observed most genes to be similarly regulated in rostral and caudal regions, but expression profiles differed during and after closure. In silico analysis found similar enrichments in both regions for biologic process terms, transcription factor binding and miRNA target motifs. Twelve genes potentially expressing alternate isoforms by region or developmental stage, and the microRNAs miR-339-5p, miR-141/200a, miR-23ab, and miR-129/129-5p are among several potential candidates identified here for future research. CONCLUSIONS Time appears to influence gene expression in the developing central nervous system more than location. These data provide a novel complement to traditional strategies of identifying genes associated with human NTDs and offer unique insight into the genes associated with normal human neurulation. Birth Defects Research (Part A) 94:683-692, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The deaths of 10 bushfire (brushfire) victims (aged 2-59 years; M/F 1:1) from the files of Forensic Science SA in Adelaide, South Australia, over an 8-year period (January 2002 to December 2009) are reported. Nine of the victims were found in or near motor vehicles. Death was attributed to incineration ( N = 5), trauma from bushfire-related vehicle crashes ( N = 2), inhalation of products of combustion with hyperthermia ( N = 1), inhalation of products of combustion ( N = 1), and undetermined ( N = 1). Death scenes covered large areas and involved many victims. Loss of infrastructure and closure of local roads owing to debris limited access and made the finding of bodies difficult. Bodies in such fires may be exposed to the damaging effects of weather and animal predation. Heat damage hindered pathological assessment with resultant delays in identification. Assessment of antemortem injuries and determination of causes of death were also complicated by the condition of some of the bodies. [ABSTRACT FROM AUTHOR]

In recent years there has been an increased incidence of export restrictions applied by developing countries to commodities and raw materials. Commodity markets may be characterized by concentration on the buyer side, with a small number of transnational intermediary firms purchasing from supplying countries and distributing to the market, and recent work has suggested that export taxes may be an optimal policy to recapture monopsony rent. However, in many commodity markets there are also a limited number of large supplying countries. This paper considers a situation where an oligopsonistic intermediary industry purchases from a small number of supplying countries, the governments of which act strategically in their policy choices both with respect to the intermediaries and any competing suppliers. In the resulting two-stage game, the paper shows that an export subsidy, rather than an export tax, may arise as the optimal intervention. [ABSTRACT FROM AUTHOR]