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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]

The spinal dorsal horn (DH) processes sensory information and plays a key role in transmitting nociception to supraspinal centers. Loss of DH inhibition during neuropathic pain unmasks a pathway from nonnociceptive Ab-afferent inputs to superficial dorsal horn (SDH) nociceptive-specific (NS) projection neurons, and this change may contribute to hyperalgesia and allodynia. We developed and validated a computational model of SDH neuronal circuitry that links nonnociceptive Ab-afferent inputs in lamina II/III to a NS projection neuron in lamina I via a network of excitatory interneurons. The excitatory pathway and the NS projection neuron were in turn gated by inhibitory interneurons with connections based on prior patchclamp recordings. Changing synaptic weights in the computational model to replicate neuropathic pain states unmasked a low-threshold excitatory pathway to NS neurons similar to experimental recordings. Spinal cord stimulation (SCS) is an effective therapy for neuropathic pain, and accumulating experimental evidence indicates that NS neurons in the SDH also respond to SCS. Accounting for these responses may inform therapeutic improvements, and we quantified responses to SCS in the SDH network model and examined the role of different modes of inhibitory control in modulating NS neuron responses to SCS. We combined the SDH network model with a previously published model of the deep dorsal horn (DDH) and identified optimal stimulation frequencies across different neuropathic pain conditions. Finally, we found that SCS-generated inhibition did not completely suppress model NS activity during simulated pinch inputs, providing an explanation of why SCS does not eliminate acute pain. [ABSTRACT FROM AUTHOR]

Background: This article focuses on a growing, global recognition of the importance of the field of interprofessional education for person-centered collaborative practice (IPECP) expressed through high-level policy and accreditation decisions/actions taking place in 5 countries. Policy decisions are used to motivate strategies related to IPECP that align with national health plans, and workforce issues. Methods: Using a collective of representative stories from around the globe, a grouping of case studies were developed to illustrate different approaches and challenges to IPECP implementation. Results: Institutions from countries of various income levels face many similar challenges in the execution, delivery, and sustainability of IPECP. All programs face issues of financing, of preparing faculty, of developing and organizing curricula, and of bridging between campus and community. Discussion: Policies are being developed that promote a global approach to the inclusion of IPECP in the accreditation and regulation of postsecondary institutions and health service organizations, in keeping with WHO National Health Workforce Accounts. Policies developed promote and demonstrate the benefits of IPECP through remote emergency learning methods. The policies also build national systems for IPECP as an integral part of continuing professional development and lifelong learning. The organization of interprofessional research programs and the increasing publication of their results of such programs will lead to a clearer understanding of the efficacy of the field of IPECP. To ensure sustainability, stakeholders and policymakers should continue to foster policies that facilitate IPECP. [ABSTRACT FROM AUTHOR]

The planktonic rotifer Brachionus calyciflorus was reported to have a behavioral response to the predatory rotifer Asplanchna , where individuals move up to a surface-film refuge. Here, I re-examine this response and also test the hypothesis that Asplanchna affects the propensity of B. calyciflorus to attach to glass surfaces. In eight experiments where B. calyciflorus was exposed to a strong Asplanchna stimulus for periods varying from 3 to 65 h, adults and juveniles showed no increase in propensity to settle at the surface film or to attach to glass surfaces. In treatments with and without Asplanchna , percentages of Brachionus free-swimming, attached to glass or settled at the surface film were 81–100%, 0–18% and 0–3%, respectively. Three types of defensive responses in planktonic rotifers are reviewed: (1) transgenerational, spine-development responses to the Asplanchna kairomone in many brachionids; (2) slow-onset (4–48 h) increases in attachment propensity due to Asplanchna , or just its kairomone, in the facultatively epizoic Brachionus rubens and Brachionus variabilis and in an attachment-prone clone of Brachionus dorcas (B. calyciflorus species complex) and (3) brief escape movements caused by disturbance immediately after contact or near-contact with various predators (Asplanchna , Daphnia , copepods) in Filinia , Keratella , Hexarthra and Polyarthra. [ABSTRACT FROM AUTHOR]

A 27-year-old male died suddenly due to cardiac tamponade arising from pericarditis complicating autoimmune polyglandular syndrome (APS) type 2. He had a history of primary Addison disease and autoimmune hypothyroidism which were corroborated at autopsy. In addition a florid fibrinous pericarditis was associated with 287 g of turbid fluid in the pericardial sac. Although pericarditis with tamponade is a potential complication of APS, it has rarely if ever, been reported as a cause of sudden death. Lethal mechanisms may involve both compressive and restrictive effects. [ABSTRACT FROM AUTHOR]

Case Presentation: A 16-year-old boy presented with 6 days of left iliac fossa pain. He had a medical history of right subtalar dislocation and appendicitis requiring laparotomy 3 years earlier, complicated by wound dehiscence. His family history was significant for his brother's sudden death 3 weeks prior after a 12-month illness with intermittent epigastric pain, weight loss, and hemoptysis. Travel history was significant for travel to the Philippines 3 years prior, in which he spent time in the hospital for appendicitis. [ABSTRACT FROM AUTHOR]

An 86-year-old woman with Alzheimer disease collapsed in her nursing home and was not able to be resuscitated. At autopsy, the major findings were in the larynx where a pedunculated oncocytic cystadenoma had occluded the glottis. Oncocytic cysts or cystadenomas of the larynx are rare histologically benign lesions that account for only 0.1–1% of laryngeal lesions. While the usual presentation is of a sensation of a mass in the throat, hoarseness, or stridor, very occasionally, there may be acute airway compromise and sudden death. Oncocytic cystadenoma should, therefore, be included in the differential diagnosis of potentially lethal obstructive laryngeal lesions. [ABSTRACT FROM AUTHOR]

A 19-year-old male was found dead in his apartment. At autopsy he was morbidly obese (Body mass index; BMI – 40.5) with multiple areas of velvety pigmented thickening of the skin in folds around the neck, in the axillae, in the inframammary regions, over the anterior waistline and groin regions and over the dorsal aspects of the feet. These had the typical appearance of acanthosis nigricans. Internal examination revealed aspiration of gastric contents into the airways. Vitreous humour biochemistry showed markedly elevated levels of both glucose (62.9 mmol/L) and β-hydroxybutyrate (13.54 mmol/L). Death was, therefore, due to aspiration pneumonia complicating diabetic ketoacidosis on a background of morbid obesity. The initial indicator of underlying diabetes, in conjunction with obesity had been acanthosis nigricans. [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]

A 27-year-old man presented to hospital with neck swelling and difficulty breathing following a recent tooth extraction. He underwent uncomplicated surgical drainage of the submandibular region after which he became acutely short of breath and collapsed and was not able to be resuscitated. At autopsy the major findings were swelling of the neck due to diffuse cellulitis with edema and neutrophil infiltrates within connective tissue and marked submucosal edema of the epiglottis, glottic inlet and tonsils sufficient to cause airway obstruction. Cultures from the site of surgical intervention showed a mixed growth of Gram positive and negative bacilli and Gram positive cocci. Death was due to airway obstruction resulting from marked submucosal edema of the glottic inlet associated with submandibular cellulitis (Ludwig's angina) following extraction of a right lower first molar tooth. Lethal Lugwig angina, although rare in current forensic practice, may still present as a cause of acute upper airway occlusion and must be considered in the differential diagnosis of significant upper airway compromise. [ABSTRACT FROM AUTHOR]

In Australia, residents can choose to remain to defend their property against bushfire but, since the 2009 Black Saturday bushfires, considerable emphasis is placed on leaving early, well in advance of a bushfire. However, many householders delay their protective decision. The insights offered by the literature into how and why some people leave early before their personal safety is threatened can inform bushfire safety policy and practice. This systematic review reports the findings of 90 papers selected from 216 identified through a search of papers in Scopus, Science Direct and Google Scholar published between 1995 and May 2021 in English. This review establishes the reasons people leave early; the influence of official and unofficial warnings; gender and other demographics; the influence of self-evacuation archetypes; planning and preparation; the influence of children and other dependents and pets; triggers initiating leaving; factors impeding and facilitating leaving; and policy issues around early leaving. This review also details 12 seminal studies that capture much of the evidence on the decision to leave early. [ABSTRACT FROM AUTHOR]

The impact and shock sensitivity of porous (granular) high-explosives is related to the formation of small mass regions of elevated temperature within the material called hot-spots by dissipative mechanisms such as plastic and friction work. Because of their small size, hot-spots are difficult to experimentally interrogate, particularly for high volumetric strain rates (εV>10,000 s-1). In this study, simulations are performed for large ensembles of deformable particles (≈4000 particles) using a combined finite and discrete element technique to characterize statistical distributions of hot-spot intensity, geometry, and spatial proximity within and behind quasi-steady, piston supported uniaxial waves in granular HMX (C4H8N8O8). Emphasis is placed on examining how the material's initial particle packing density, characterized by its effective solid volume fraction [lowercase_phi_synonym]s,0, affects hot-spot statistics for pressure dominated waves corresponding to piston speeds within the range 300≤Up≤500 m/s. Predictions indicate that hot-spot intensity is only marginally affected by initial porosity (1-[lowercase_phi_synonym]s,0) for all piston speeds, whereas hot-spot size, number density, volume fraction, and volume specific surface area appreciably increase with porosity and exponentially increase with piston speed. Minor variations in particle shape are predicted to be largely inconsequential. Joint distributions of hot-spot intensity and size are combined with thermal explosion data to identify and examine critical hot-spots that quickly react behind waves. These results indicate that the observed increase in sensitivity with initial porosity for sustained loading is likely due to an increase in hot-spot size and number rather than intensity. [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]

Experiments with two strains of the facultative epibiont, Brachionus rubens, tested the ability of this rotifer to avoid predation by the rotifer Asplanchna, and its propensity for sexual reproduction and consequent diapause at different population densities. Unlike some congeners, B. rubens did not have a morphological response to Asplanchna by developing longer spines or a larger body. However, it responded to this predator, and its kairomone, with a behavioral defense: a higher propensity to transition from free-swimming to attachment, typically in dense aggregations. Attached individuals were less likely to be captured and ingested, so that B. rubens outlived Asplanchna in some mixed-species cultures. Although crowding induces sex in some congeners, it did not do so in B. rubens. Instead, the proportion of sexual (mictic) daughters produced by females cultured in different volumes (0.5–60 ml) was density-independent: ~ 0.2 for the Argentina strain and ~ 0.6 for the Australia strain. Such fixed levels of sex have rarely been detected in rotifers. In B. rubens, they may be a strategy to ensure some sex with diapause at all times, but permit continued population growth via female parthenogenesis at the very high densities that normally occur on hosts and other surfaces. [ABSTRACT FROM AUTHOR]

An 86-year-old woman with a history of angioedema was found dead at her home address. She had recently complained of a swollen tongue. At autopsy the tongue was grossly edematous, protruding from the mouth. There was also marked edema of the tonsillar fossae, epiglottis and glottic inlet, causing critical obstruction. Histology of the tongue and upper airway demonstrated marked submucosal edema. Death was attributed to upper airway obstruction due to angioedema of the tongue, oropharynx and glottic inlet. Angioedema is characterized by localized non-pitting edema of the deep dermis and subcutaneous/submucosal tissues. It may be acute or chronic, acquired or inherited. Sudden death may result from critical airway occlusion, although both stroke and ischemic heart disease are known to occur. Post mortem genetic testing for hereditary variants can be conducted for SERPING1 gene and F12 gene/THR328 mutations. [ABSTRACT FROM AUTHOR]

Cells with 'signet-ring' appearance were found at post-mortem examination of a man with a history of chronic illness, weight loss and multiple regions of 'bowel thickening' during life. Due to the decedent's history, the finding raised the possibility of disseminated signet-ring adenocarcinoma. However, the vacuoles did not stain for mucin and the cells did not stain for keratin. The cells did stain for calretinin and so a diagnosis of signet ring mesothelioma was considered. However, it was suggested that the cells with a cytoplasmic vacuole displacing the nucleus to one side producing the signet-ring appearance were instead atrophic fat cells. This was subsequently proven by Oil Red O staining. [ABSTRACT FROM AUTHOR]

Providing quality health care is the core purpose for health systems, and it is only possible with adequate capacity among the workforce to provide the required services. Addressing the requirements for, and supply of, the health workforce (workforce planning) is essential for strengthening health systems. There is a global recognition that interprofessional education (IPE) is critical to achieving universal health care. In this introductory paper we discuss how IPE is a key factor within needs-based health systems strengthening and Human Resources for Health (HRH) planning. This perspective is illustrated through six case studies from countries around the globe which provide discourse on how the integration of IPE/IPC with needs-based workforce planning can contribute to strengthening the health systems. Three key learnings arise from the case studies – 1) IPE is important to meet health care needs of populations efficiently and effectively; 2) integrated needs-based planning provides a framework within which IPE has an integral role, and 3) stakeholders from both health and education are critical to the process of seamless integration of IPE across the continuum of health systems. [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]

Lividity or livor mortis occurs when blood settles in dependent areas after death due to gravitational effects. Patterned lividity may result from a body lying against a variety of surfaces. Two case are presented where lividity was prevented by tight fitting elastic underwear except in areas where letters from the manufacturers' names had elevated the material, thus permitting capillaries in the underlying skin to fill. This type of patterned lividity may act as a useful record of the type of clothing being worn at the time of death and in the hours following. [ABSTRACT FROM AUTHOR]

An 84-year-old woman with a history of weight loss, anorexia and episodic vomiting was admitted to hospital where she died soon afterwards. Her diagnosis was acute renal injury due to dehydration and malnutrition. At autopsy the body was cachectic with a small intestinal obstruction due to herniation through a defect at the anterolateral aspect of the obturator foramen. A poorly differentiated adenocarcinoma of the gastroesophageal junction was also identified with small peripheral pulmonary thromboemboli. Death was due to small bowel obstruction from a left obturator hernia with scattered peripheral pulmonary thromboemboli complicating cachexia due to gastroesophageal adenocarcinoma. Obturator hernias are called the "little old lady's hernia" and occur mainly in elderly, multiparous and malnourished women. The broader female pelvis and wider obturator canal with laxity of ligaments and loss of preperitoneal adipose tissue padding around the canal predispose to herniation. This rare hernia is often first identified at autopsy. [ABSTRACT FROM AUTHOR]

The planktonic rotifer, Brachionus calyciflorus, displays extensive variation in the length of its anterior and posterior spines. Notably, posterolateral spines may be absent or near body length. Studies of laboratory and natural populations have identified the different factors controlling this variation and have investigated the trade-offs associated with increased spine development. Low temperature and low food availability can induce modest spine elongation that may reduce sinking rate. A kairomone released by the carnivorous rotifer Asplanchna induces pronounced spine elongation, without detectable reproductive cost, that can provide an effective defense against this predator. Endogenous mechanisms also operate: Spine development is inhibited in females hatched from fertilized resting eggs and can be promoted by increasing maternal age. Genetic variation for the length of spines in both noninduced (default) and induced phenotypes occurs among and within populations. Asplanchna in natural communities likely leads to seasonal selection for genotypes that can develop increasingly long spines. [ABSTRACT FROM AUTHOR]

Two morphologically distinct Brachionus calyciflorus hatched from Lake Littra sediment: a typical B. calyciflorus Pallas and B. (calyciflorus) "Darling", a reproductively isolated, globular taxon without posteromedian spines. The Darling taxon is well defended against Asplanchna by its large size (adult lorica length ≥ 310 μm) and short (~50 μm) Asplanchna-induced posterior spines that protect small, vulnerable neonates. The typical B. calyciflorus is smaller (adult lorica length 169-195 μm) and is a mixture of interbreeding clones with or without constitutive posterolateral spines. In one of the former clones, adult posterolateral spine length increased significantly with maternal age, from ~62 to 78 μm. Asplanchna induced increased lorica length and pronounced spine development in all clones and its effect on females with constitutive posterolateral spines was additive. With Asplanchna, posterolateral spine length was 159 μm for a clone without constitutive posterolateral spines and 207 μm in a clone with 74μm-long constitutive posterolateral spines. Coexistence of clones with and without constitutive posterolateral spines suggests a trade-off between the benefit of long defensive spines and some cost to spine development. It likely is maintained by fluctuating directional selection in response to changing Asplanchna abundance and by a sediment bank of diapausing eggs produced by sexual reproduction. [ABSTRACT FROM AUTHOR]

Brush abrasions are superficial injuries that occur when a body has been dragged over a rough surface. A 38-year-old male cyclist was dragged, by a truck that had collided with him, for a number of kilometres before being left behind. Post-mortem examination revealed numerous brush abrasions that were associated with abraded injuries in the deeper tissues from contact with the road surface. Death was due to closed head injury and haemorrhage from multiple severe injuries from dragging. The case shows the usefulness of patterned abrasions in helping to determine the sequence of lethal events in such collisions. It also demonstrates that brush abrasions may sometimes be associated with similar but deeper underlying injuries that arise from the same mechanism. Dragging injuries can be lethal if there is extension into deeper tissues and vasculature. [ABSTRACT FROM PUBLISHER]

This paper reviews our very limited knowledge about resting-egg hatching and early population development in planktonic rotifers. Hatching of stem females from resting eggs may occur soon after resting eggs are produced, but perhaps usually it is delayed by a minimum obligate diapause, by a requirement for seasonal temperature changes, or by sinking to sediment environments that prevent hatching. In deep-water sediments, hatching probably is inhibited by low oxygen, darkness, or low temperature, so that eggs likely hatch following resuspension during water-column turnover. Populations should develop primarily by female parthenogenesis and have relatively low clonal diversity. By contrast, in shallow-water sediments, eggs are more likely to experience conditions conducive to hatching and to be resuspended into the water column. Populations may develop by massive emergence of stem females as well as by female parthenogenesis and thus have a very high clonal diversity. Stem females of some species are particularly fit for colonization of new habitat. First, compared to females hatched from parthenogenetic eggs, they can have a greater lipid reserve that enhances survival and reproduction. Second, amictic stem females can contain a transmissible factor that inhibits sexual reproduction and diapause for several to many successive generations, thus promoting rapid reproduction via female parthenogenesis. [ABSTRACT FROM AUTHOR]

This paper proposes a model-based notion of ‘submicro representations of chemical reactions’. Based on three structural models of matter (the simple particle model, the atomic model and the free electron model of metals), we suggest there are two major models of reaction in school chemistry curricula: (a) reactions that are simple rearrangements of particles, where particles are the most basic units of rearrangement and do not change their identity in the reactions, and (b) reactions involving the interactions of chemical species with – depending on the type of reaction – electrons and protons. In the latter case, chemical species change their identities/structures in reactions; for example, atoms become ions. Based on these two models, we analysed how 18 Grade 10–11 students mentally visualised the reaction between magnesium and hydrochloric acid. Each student was interviewed twice – once after they were taught the reactions of acids and once after they learned about redox. Their visualisations could be fitted into these two models. There was a developmental trend among the students, who progressed from the simple model to the more sophisticated model. None of the students regressed. Curriculum planning and teaching should consider how students should be helped to learn about different reaction models. [ABSTRACT FROM AUTHOR]

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]

Purpose The purpose of this paper is to examine the level of physical preparation for bushfire among Victorian residents in established high risk bushfire locations, and to assess whether these levels of preparation changed over time.Design/methodology/approach Data were analysed from a telephone survey among Victorian residents (n=614-629) living in high risk bushfire locations over a three-year period (2012-2014). The survey measured residents’ bushfire awareness, knowledge, planning, preparation and engagement with bushfire services. This paper focusses on the extent to which respondents undertook physical preparatory bushfire activities over the three-year period using: first, principal components analysis to generate a single preparation variable by identifying a smaller number of uncorrelated variables (or principal components) from a larger set of data, second, analysis of variance to assess differences in preparation scores between years, and third, Tukey’s honest significant difference test to confirm where the differences occurred between groups.Findings Results indicated only moderate levels of physical preparation for bushfires amongst respondents. The activities that respondents rated the lowest were: “having protective covers for windows” and “having firefighting equipment to protect the house”. A significant difference in total preparation scores over time was observed, F(2, 1,715)=6.159, p<0.005, with lower scores in 2012 compared with 2013 and 2014 scores.Social implications This study found some marginal improvements in levels of physical bushfire preparation from 2012 to 2014. However, the results indicate only moderate levels of preparation overall, despite respondents living in established high risk locations.Originality/value This study provides evidence for the current levels of preparedness in high risk bushfire communities, and emphasises the need for future initiatives to focus on specific bushfire preparation activities but also to consider the broader range of interventions that are likely to contribute to desired safety outcomes. [ABSTRACT FROM AUTHOR]

Municipal solid waste management is one of the major environmental problems of developing countries. Investments in solid waste management would not only translate into jobs and income but also a cleaner environment. Over years a number of solid waste management technologies have been carried out in many developing parts of the world. Some were successful in generating lasting impacts on the improvement of solid waste management, however, many technologies failed due to unsustainability. This is partly attributed to differences in waste characteristics between developed countries and the less developed countries and the resource constraints in less developed countries. On the other hand, less developed countries are also known for being energy deprived and thus energy recovery as sustainable waste management technology is advocated for in these countries. This paper seeks to review and assess the energy recovery potential from the various sustainable waste technologies in Uganda. The advantages attached to such technologies will be assessed and evaluated. In a further step, a comparative analysis with traditional energy sources like hydro-electricity power and petroleum products powered generators is also presented and discussed. This study concludes that renewable energy sources present Uganda with a rare opportunity to elevate millions out of energy poverty. [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]

A 20-year-old previously well man drowned after performing a back-flip off a bridge into a river. At autopsy no significant injuries or organic illness were identified. An unusual incidental finding was a double chambered left ventricle, or so-called “heart within a heart”, with the left ventricle subdivided into two separate chambers by a muscular septum. Awareness of this entity in forensic casework is important as this anomaly, despite its dramatic appearance, is not associated with anomalous conduction tracts or arrhythmogenic conditions, and so is usually a completely incidental finding at autopsy. [ABSTRACT FROM AUTHOR]

Sleeping accidents are a particular risk for infants and young children as they lack an understanding of potentially dangerous situations and are unable to self-extricate. These situations may result in deaths from asphyxia. While safety campaigns have focused on the faulty design of cots that are available for sale, modification of cots at home represents another potential problem area. A 17-month-old girl was found dead with her head wedged between the top side rail of her cot and a broomstick, which had been attached in an attempt to raise the height of the cot side. Death was due to neck compression from head entrapment. This case demonstrates that infant and toddler safe sleeping programmes should alert carers to the potential dangers of structurally altering cots or beds. Home modifications may create dangerous gaps that could result in entrapment with lethal neck compression; such alterations should be carefully assessed and documented by forensic death scene investigators. [ABSTRACT FROM PUBLISHER]

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]

This study investigated students' interpretation of diagrams representing the human circulatory system. We conducted an interview study with three students aged 14–15 (Year 10) who were studying biology in a Hong Kong school. During the interviews, students were asked to interpret diagrams and relationships between diagrams that represented aspects of the circulatory system. All diagrams used in the interviews had been used by their teacher when teaching the topic. Students' interpretations were expressed by their verbal response and their drawing. Dual coding theory was used to interpret students' responses. There was evidence that one student relied on verbal recall as a strategy in interpreting diagrams. It was found that students might have relied unduly on similarities in spatial features, rather than on deeper meanings represented by conventions, of diagrams when they associated diagrams that represented different aspects of the circulatory system. A pattern of students' understanding of structure–behaviour–function relationship of the biological system was observed. This study suggests the importance of a consistent diagrammatic and verbal representation in communicating scientific ideas. Implications for teaching practice that facilitates learning with diagrams and address students' undue focus on spatial features of diagrams are discussed. [ABSTRACT FROM PUBLISHER]

Brachionus variabilis, a facultative epibiont on cladocerans, has a pronounced morphological response to Asplanchna. Adult amictic females of the Asplanchna-induced morph, compared with those of the basic or non-induced morph, had a 13% larger lorica, 150% longer posterior spines and 30–40% longer anterior spines. Similar responses occur in many other brachionid rotifers as an effective defense against Asplanchna predation, but the response of B. variabilis is surprising. The large size and epizoic habit of B. variabilis should provide good protection against this predator. Also, a smaller epizoic congener (Brachionus rubens) readily ingested by Asplanchna has no morphological response to it. Brachionus variabilis also has a pronounced behavioral response to Asplanchna. Without Asplanchna, most individuals are actively swimming, with only a small proportion of them attached to surfaces. With Asplanchna, the proportion of attached individuals is much higher. Significant attachment responses in both young and adult individuals occurred shortly (∼5 h) after exposure to live Asplanchna (three experiments) or to its kairomone (five experiments), but not to a Daphnia kairomone. The Asplanchna-enhanced propensity for attachment to surfaces, possibly including cladoceran hosts, may be an additional defense against this predator. This is the first report of a predator kairomone inducing a behavioral shift in a rotifer. [ABSTRACT FROM PUBLISHER]

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]

Studies analyzing explanations that have been constructed by science students have found that they were generally weak and lack necessary features. The goal of this study was to establish the competencies that one needs to construct a scientific explanation. Scientific explanations can be looked at in three ways, in terms of their function, form and level, as being essentially sign-making processes. Taking a case study approach and using Lemke's multimodal framework, we analyzed the scientific explanation of an electromagnetic induction phenomenon constructed by one high school student. We found that such a construction involves the complex coordination of different types of signs, not only to represent the entities in the phenomenon, but also to support thinking and reasoning about it at abstract levels. Scientific conventions and rules, and everyday material and social tools were found to be crucial in shifting from one level of abstraction to another. The findings highlight the importance of developing the skillful use of schemes of scientific representation by students and familiarizing them with commonly encountered contexts. [ABSTRACT FROM PUBLISHER]

Abstract: Objective: To evaluate value of adding non-contrast MR angiographic sequence (In-Flow Inversion Recovery [IFIR]) to standard fat-suppressed T1-weighted postcontrast sequence (3D spoiled gradient echo [3D-GRE]) for evaluating hepatic arterial anatomy. Methods: Retrospective evaluation of 30 consecutive patients undergoing multiphase liver MRI. Individual vessels for IFIR/3D-GRE sequences were evaluated by two blinded readers using a four-point scale. Statistical analysis was performed using the Wilcoxon signed-rank test for vessel conspicuity between IFIR/3D-GRE sequences. Results: IFIR alone diagnostically imaged 8.1% of vessels, 3D-GRE alone 25.8%, 55.8% by both 3D-GRE/IFIR, and 10.3% of vessels by neither. Two patients with variant vascular anatomy were visualized with both sequences. Addition of IFIR to 3D-GRE resulted in statistically significant increase in arterial visualization (p <0.001), 10% relative increase in identified vessels, and 3–5mi increase in acquisition time for total scan time of 30–35min. Conclusions: IFIR may be a useful adjunct to 3D-GRE in hepatic angiography without adding considerably to scan time. 10% more hepatic arteries were seen when combining information from IFIR/3D-GRE vs. 3D-GRE alone. [Copyright &y& Elsevier]

This study investigated the mental representations of metallic bonding and the malleability of metals held by three male students aged 14–15 (Year 10) who were attending a Hong Kong school. One student was selected by their chemistry teacher as representing each of the highest, the medium, and the lowest level of attainment in chemistry in a school that admitted students of average general attainment. The students were interviewed and their understandings probed through their provision of drawings and their interpretation of the diagrams that had been previously used by their teacher. Dual coding theory was used to interpret the relative significance of visual and verbal input and the interaction between the two for their understanding. There was evidence that students relied on verbal recall in providing their initial understandings and showed an appreciation of the nature of the structural components of the electron-sea model of metallic bonding. However, they varied in terms of their appreciation of the electrostatic force which was responsible for the malleability of metals. The study suggests that a clearer understanding of the electrostatic force involved can be attained when students experience visual and verbal representations simultaneously, a conclusion supported by dual coding theory. Principles for good practice in using diagrams in teaching are discussed. [ABSTRACT FROM PUBLISHER]

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]

Successful aging (SA) is a multidimensional phenotype involving living to older age with high physical function, preserved cognition, and continued social engagement. Several domains underlying SA are heritable, and identifying health-promoting polymorphisms and their interactions with the environment could provide important information regarding the health of older adults. In the present study, we examined 263 cognitively intact Amish individuals age 80 and older (74 SA and 189 'normally aged') all of whom are part of a single 13-generation pedigree. A genome-wide association study of 630,309 autosomal single nucleotide polymorphisms (SNPs) was performed and analyzed for linkage using multipoint analyses and for association using the modified quasi-likelihood score test. There was evidence for linkage on 6q25-27 near the fragile site FRA6E region with a dominant model maximum multipoint heterogeneity LOD score = 3.2. The 1-LOD-down support interval for this linkage contained one SNP for which there was regionally significant evidence of association (rs205990, p = 2.36 × 10). This marker survived interval-wide Bonferroni correction for multiple testing and was located between the genes QKI and PDE10A. Other areas of chromosome 6q25-q27 (including the FRA6E region) contained several SNPs associated with SA (minimum p = 2.89 × 10). These findings suggest potentially novel genes in the 6q25-q27 region linked and associated with SA in the Amish; however, these findings should be verified in an independent replication cohort. [ABSTRACT FROM AUTHOR]

The Pan-American Health Organization (PAHO) and World Health Organization have encouraged countries across Latin America and the Caribbean (LAC) to incorporate interprofessional education and collaborative practice (IPECP) into policies on the health workforce, and support policymakers in expanding its use. PAHO recommend countries to promote the development of interprofessional teams in integrated health services networks using IPECP. The creation of the Regional Network for Interprofessional Education in the Americas, the mobilization of a series of IPECP regional meetings, and the development of national IPECP action plans are the most promising results achieved thus far. This report describes the process of implementing IPECP in LAC countries as an innovative initiative in interprofessional health policy. [ABSTRACT FROM AUTHOR]

In many small planktonic rotifers, predator kairomones induce the development of longer spines, which can provide effective post-contact defense against the predators. This review briefly discusses potential trade-offs associated with pronounced spine development, focuses on an evaluation and synthesis of experimental work comparing the reproductive potential of basic (non-induced) and Asplanchna-induced morphs and suggests areas for future research. To date, the only convincing evidence for an association between induced spine development and reduced reproduction is for Keratella testudo. This rotifer has a dense lorica (skeleton), so that elongated spines increase its sinking rate and thus presumably an offsetting swimming effort. In contrast, several studies with Brachionus calyciflorus and Keratella tropica, which have a thin lorica, showed that morphs with pronounced spine development reproduced at the same rate as basic morphs. In other studies with several different species, and also with B. calyciflorus, the presence of Asplanchna did inhibit reproduction. However, this inhibition generally was not clearly related to Asplanchna density or the degree of spine development, and could not be attributed to a defense cost. While predator-induced morphs of some species do not have a reduced reproductive potential in the laboratory, they may be at a disadvantage in certain interactions or conditions occurring in more complex, natural ecosystems. Such environmental costs, or plasticity costs resulting from the evolution of mechanisms for detecting and responding to predators, may explain why long spines in some rotifers are an inducible rather than a constitutive defense. [ABSTRACT FROM AUTHOR]

Abstract: Interprofessional education for collaborative practice is an important innovation globally and in US health professions education. The recent spotlight on interprofessional education in the United States was launched by a series of reports in the US Institute of Medicine''s Quality Chasm series. They raised concerns over medical errors and health care quality as significant sources of morbidity and mortality in the United States and proposed health professions'' education for patient-centered, team-based care as one means to address these concerns. Starting in 2007, binational, biennial conferences on interprofessional education have been held to synergize interprofessional education developments in the United States and Canada. In 2011, Collaborating Across Borders III, in Tucson, Arizona, drew 750 participants from 11 countries. The conference focused on interprofessional competency frameworks; strategies for preparing students for interprofessional practice; tailoring of learning environments for interprofessional education; and developing policy, infrastructure, culture, and faculty leadership for interprofessional education. [Copyright &y& Elsevier]