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Using validated psychological assessment instruments, this study examined the psychological distress associated with potential language barriers experienced by over 135 000 Puerto Rican residents who either temporarily or permanently migrated to the continental United States with the landfall of Hurricane Maria in 2017.
Participants were Puerto Rican residents (n = 107) who remained in Puerto Rico (control) or left the island for at least 3 months because of Hurricane Maria (migrants). Participants completed an online survey in their preferred language (Spanish or English), which assessed self-reported English language proficiency, Kessler Psychological Distress Scale (K6), Posttraumatic Stress Disorder Checklist for DSM 5, Patient Health Questionnaire 9-item depression scale, and the Generalized Anxiety Disorder 7-item scale. It was hypothesized that migrants with lower self-reported English proficiency would have comparatively higher indices of post-disaster distress than those with a higher proficiency.
Dividing the migrant group by preferred language for questionnaire completion, the Fisher’s exact test showed significant differences in prevalence of severe mental distress, as defined by K6 scores above 13, between the Spanish-preferring migrants (30.4%), English-preferring migrants (0%), and controls (9.6%).
Our results support a possible correlation between decreased language proficiency in post-disaster migrants and a higher risk factor for severe mental distress.
The ventricular assist device is being increasingly used as a “bridge-to-transplant” option in children with heart failure who have failed medical management. Care for this medically complex population must be optimised, including through concomitant pharmacotherapy. Pharmacokinetic/pharmacodynamic alterations affecting pharmacotherapy are increasingly discovered in children supported with extracorporeal membrane oxygenation, another form of mechanical circulatory support. Similarities between extracorporeal membrane oxygenation and ventricular assist devices support the hypothesis that similar alterations may exist in ventricular assist device-supported patients. We conducted a literature review to assess the current data available on pharmacokinetics/pharmacodynamics in children with ventricular assist devices. We found two adult and no paediatric pharmacokinetic/pharmacodynamic studies in ventricular assist device-supported patients. While mechanisms may be partially extrapolated from children supported with extracorporeal membrane oxygenation, dedicated investigation of the paediatric ventricular assist device population is crucial given the inherent differences between the two forms of mechanical circulatory support, and pathophysiology that is unique to these patients. Commonly used drugs such as anticoagulants and antibiotics have narrow therapeutic windows with devastating consequences if under-dosed or over-dosed. Clinical studies are urgently needed to improve outcomes and maximise the potential of ventricular assist devices in this vulnerable population.
Discovery of strongly-lensed gravitational wave (GW) sources will unveil binary compact objects at higher redshifts and lower intrinsic luminosities than is possible without lensing. Such systems will yield unprecedented constraints on the mass distribution in galaxy clusters, measurements of the polarization of GWs, tests of General Relativity, and constraints on the Hubble parameter. Excited by these prospects, and intrigued by the presence of so-called “heavy black holes” in the early detections by LIGO-Virgo, we commenced a search for strongly-lensed GWs and possible electromagnetic counterparts in the latter stages of the second LIGO observing run (O2). Here, we summarise our calculation of the detection rate of strongly-lensed GWs, describe our review of BBH detections from O1, outline our observing strategy in O2, summarize our follow-up observations of GW170814, and discuss the future prospects of detection.
Gurga Chiya and Tepe Marani are small, adjacent mounds located close to the town of Halabja in the southern part of the Shahrizor Plain, one of the most fertile regions of Iraqi Kurdistan. Survey and excavation at these previously unexplored sites is beginning to produce evidence for human settlement spanning the sixth to the fourth millennia, c. 5600–3300 cal. b.c. In Mesopotamian chronology this corresponds to the Late Neolithic through to Chalcolithic periods; the Halaf, Ubaid, and Uruk phases of conventional culture history. In Iraqi Kurdistan, documentation of these periods—which witnessed many important transformations in prehistoric village life—is currently very thin. Here we offer a preliminary report on the emerging results from the Shahrizor Plain, with a particular focus on the description of material culture (ceramic and lithic assemblages), in order to establish a benchmark for further research. We also provide a detailed report on botanical remains and accompanying radiocarbon dates, which allow us to place this new evidence in a wider comparative framework. A further, brief account is given of Late Bronze Age material culture from the upper layers at Gurga Chiya. We conclude with observations on the significance of the Shahrizor Plain for wider research into the later prehistory of the Middle East, and the importance of preserving and investigating its archaeological record.
Community structure, species composition, and changes over time after
disturbances are frequently studied using common descriptors. We used rank
abundance distribution plots (RADs), Rényi entropy plots, common theoretical
community models, ordination analysis of similarities (ANOSIM and Clusters),
and abundance spectra analyses to study the effects of a gradual natural
population decline and an anthropogenic punctuated disturbance on the
structure of octocoral communities in Panama, considered a hot spot area for
octocoral diversity in the Tropical Eastern Pacific. Over a 17-month period,
no significant change was found in community structure after a natural
yearly population decline of 25.2%. After a disturbance, however, different
recovery trajectories were observed in various coral communities. Possible
physical and biological explanations for the observed differences include
initial local species diversity and abundance, species life history
patterns, colony morphology, and the geographical location of the community.
Differences in community structure between study sites were best described
using a combination of community descriptors, RADs, and abundance spectra.
Rényi plots were useful in identifying changes in community structure,
whereas the extent of the changes was best evaluated using ANOSIM and
Stress caused by early weed competition is known to delay the rate of maize
development which may result in a decrease in kernel number. Kernel number
in maize is correlated negatively with the length of the anthesis-silking
interval (ASI). A short ASI has been identified as an easily measured,
visual trait which may identify enhanced drought tolerance in maize. Field
studies were conducted to test whether: (1) delaying weed control would
result in a lengthening of ASI in both a drought tolerant and non-drought
tolerant maize hybrid and (2) the presence of drought tolerance genetics
comes at a physiological cost, resulting in a greater yield reduction under
weedy conditions. In this study, the response of a drought tolerant hybrid
with its non-drought tolerant near-isoline was compared to seven different
timings of weed control using wheat as a surrogate competitor. Results
confirmed that there was no treatment by hybrid interaction at any site–yr
for any of the parameters evaluated. Delaying weed control reduced plant
height, leaf tip number, shifted and reduced biomass accumulation, kernel
number and grain yield and lengthened ASI for both hybrids. Although yield
losses occurred with the delay in weed control timing, no yield differences
were observed between hybrids suggesting that there was no additional
physiological cost associated with the drought tolerant traits. The drought
tolerant hybrid, however, was found to have a shorter ASI, lower kernel
number and higher kernel wt compared to the non-drought tolerant hybrid.
This study confirmed that delaying weed control can influence the length of
ASI, which is an important drought tolerant trait. The lengthening of ASI by
early weed competition resulted in a rate of yield loss of 0.13 T
ha−1 growing degree days (GDD)−1 when averaged
across both hybrids and all treatments.
Even though the full process of seed dispersal is the combination of movement mode and distance, deposition, successful germination and survival (Nathan 2006, Westcott et al. 2005), relatively few studies have documented the role of mammals as facilitators of germination and survival (Paine & Harms 2009). In particular, the effectiveness of large terrestrial mammals (>50 kg) as effective dispersers of large seeds is poorly known, but has been linked to the treatment of the seeds in their digestive system, the deposition of viable seeds in nutrient-rich environments (faeces) and favourable sites. Other aspects related to long-distance movements, defecation patterns and home-range size are frequently cited as factors that favour the deposition of seeds far from parent trees, which is expected to reduce predation and intraspecific competition, and enhance fitness (Schupp et al. 2002). We addressed these issues through a large-scale field experiment.
The distribution and dynamics of plant populations depend on the recruitment of young individuals, which is influenced by seed production, animal seed dispersal, dispersal distance, and the deposition of seeds in favourable places for seed germination/establishment and seedling survival. In particular, seeds dispersed over long distances will likely encounter new environmental conditions that occur at large spatial scales, with seed and seedling survival influenced by the adaptation of plant populations to soil and climate conditions. In this paper, it is hypothesized that seed germination and seedling survival probabilities depend on seed origin and deposition sites. A reciprocal seed and seedling transplant experiment was carried out with zapote seeds (Manilkara zapota) to determine the effect of origin and deposition sites on seed germination and seedling survival over a year in the Greater Calakmul Region of Mexico. Two origin and two deposition sites were selected that show different soil moisture levels within the habitat of the Baird's tapir, a major seed disperser of M. zapota seeds. The results show that sites of origin and deposition influenced seed germination and seedling survival probabilities. This suggests that the displacement of seeds far from parent trees, while potentially reducing intraspecific competition, does not ensure their survival, and that seeds need to be deposited in microsites within their environmental tolerance for dispersal to be successful. Furthermore, this paper emphasizes the importance of field experiments to provide strong inference about the effects of environmental conditions on recruitment and distribution of plant species.
The HealthAgents project aims to provide a decision support system for brain tumour diagnosis using a collaborative network of distributed agents. The goal is that through the aggregation of the small data sets available at individual hospitals, much better decision support classifiers can be created and made available to the hospitals taking part. In this paper, we describe the technicalities of the HealthAgents framework, in particular how the interoperability of the various agents is managed using semantic web technologies. On the broad scale the architecture is based around distributed data-mart agents that provide ontological access to hospitals’ underlying data that has been anonymized and processed from proprietary formats into a canonical format. Classifier producers have agents that gather the global data from participating hospitals such that classifiers can be created and deployed as agents. The design on a microscale has each agent built upon a generic-layered framework that provides the common agent program code, allowing rapid development of agents for the system. We believe that our framework provides a well-engineered, agent-based approach to data sharing in a medical context. It can provide a better basis on which to investigate the effectiveness of new classification techniques for brain tumour diagnosis.
In this paper, we analyze the special security requirements for software support in health care and the HealthAgents system in particular. Our security solution consists of a link-anonymized data scheme, a secure data transportation service, a secure data sharing and collection service, and a more advanced access control mechanism. The novel security service architecture, as part of the integrated system architecture, provides a secure health-care infrastructure for HealthAgents and can be easily adapted for other health-care applications.
Survey and excavation by the Burials and Identity team of the Desert Migrations Project (DMP) focused in 2011 on the so-called Royal Cemetery of the Garamantes close to the Jarma escarpment, a few km south of Old Jarma. This Late Garamantian cemetery contains two distinct zones (GSC030 and GSC031) of monumental rectangular stepped tombs, which were plaster-coated and fronted by massive offering tables and stelae. Previous dating evidence has suggested they span the fourth to sixth centuries AD. However, many questions remain about the cemetery and the overall recording of the monuments had hitherto been left incomplete. The 2011 work focused on the excavation of one of the larger monuments in GSC030 and several of the smaller tombs in the neighbouring GSC031, along with an overall survey of both cemetery areas and a detailed record of the stelae and offering tables still present in considerable numbers. In addition, the team made a survey along the escarpment between the Royal Cemetery and Zinkekrā, completing and uniting the various surveys carried out by the DMP around Zinkekrā, Watwāt and the Jarma Escarpment. A survey of foggaras and settlement in the ad-Dīsa embayment was also undertaken.
The ‘Burials and Identity’ team of the Desert Migrations Project carried out two main excavations in the 2009 season, at the monumental Garamantian cemeteries of TAG001 and TAG012, by the Taqallit headland. In addition, a detailed survey was made of cemeteries and other sites on the west side of the Taqallit headland, to set the two main cemetery excavations in context. A total of over 2,100 individual burials was recorded in this small area of a few square kilometres. This cemetery survey was combined with further research on the well-preserved foggara systems in this area, which originate at the escarpment among the cemeteries and run in a north-westerly direction towards the valley centre, where some additional Garamantian settlement sites were also located. The foggara research also involved excavation at four locations to try to elucidate issues relating to the dating of these.
A total of 22 burials was investigated at TAG001, an imposing cemetery of stone-built stepped tombs that had been badly damaged by illegal bulldozing in the 1990s. Although these had been subjected to robbing at some point in the past, many preserved considerable parts of the skeletons buried within and some surprisingly complete artifact groups. Of particular importance are a series of Garamantian necklaces in ostrich eggshell, carnelian and glass beads, which we were able to lift in perfect sequence and restring. At TAG012, about 2 km north of the Taqallit headland, we excavated an area of a mudbrick cemetery, exposing 12 square/rectangular tombs. Two further burials were excavated at the dispersed cemetery TAG006, in both cases involving tombs that had an interesting stratigraphical relationship with foggara spoil mounds.
This book is designed for a one- or two-quarter course in continuum mechanics for first-year graduate students and advanced undergraduates in the mathematical and engineering sciences. It was developed, and continually improved, by over four years of teaching of a graduate engineering course (ME 238) at Stanford University, USA, followed by over four years of teaching of an advanced undergraduate mathematics course (MA3G2) at the University of Warwick, UK. The resulting text, we believe, is suitable for use by both applied mathematicians and engineers. Prerequisites include an introductory undergraduate knowledge of linear algebra, multivariable calculus, differential equations and physics.
This book is intended both for use in a classroom and for self-study. Each chapter contains a wealth of exercises, with fully worked solutions to odd-numbered questions. A complete solutions manual is available to instructors upon request. A short bibliography appears at the end of each chapter, pointing to material which underpins, or expands upon, the material discussed here. Throughout the book we have aimed to strike a balance between two classic notational presentations of the subject: coordinate-free notation and index notation. We believe both types of notation are helpful in developing a clear understanding of the subject, and have attempted to use both in the statement, derivation and interpretation of major results. Moreover, we have made a conscious effort to include both types of notation in the exercises.
Chapters 1 and 2 provide necessary background material on tensor algebra and calculus in three-dimensional Euclidean space.
A concise account of various classic theories of fluids and solids, this book is for courses in continuum mechanics for graduate students and advanced undergraduates. Thoroughly class-tested in courses at Stanford University and the University of Warwick, it is suitable for both applied mathematicians and engineers. The only prerequisites are an introductory undergraduate knowledge of basic linear algebra and differential equations. Unlike most existing works at this level, this book covers both isothermal and thermal theories. The theories are derived in a unified manner from the fundamental balance laws of continuum mechanics. Intended both for classroom use and for self-study, each chapter contains a wealth of exercises, with fully worked solutions to odd-numbered questions. A complete solutions manual is available to instructors upon request. Short bibliographies appear at the end of each chapter, pointing to material which underpins or expands upon the material discussed.
In this chapter we state various axioms which form the basis for a thermo-mechanical theory of continuum bodies. These axioms provide a set of balance laws which describe how the mass, momentum, energy and entropy of a body change in time under prescribed external influences. We first state these laws in global or integral form, then derive various corresponding local statements, primarily in the form of partial differential equations. The balance laws stated here apply to all bodies regardless of their constitution. In Chapters 6–9 these laws are specialized to various classes of bodies with specific material properties, via constitutive models.
The important ideas in this chapter are: (i) the balance laws of mass, momentum, energy and entropy for continuum bodies; (ii) the difference between the integral form of a law and its local Eulerian and Lagrangian forms; (iii) the axiom of material frame-indifference and its role in constitutive modeling; (iv) the idea of a material constraint and its implications for the stress field in a body; (v) the balance laws relevant to the isothermal modeling of continuum bodies.
In order to motivate the contents of this chapter it is useful to recall some basic ideas from the mechanics of particle systems. To this end, we consider a system of N particles with masses mi and positions xi as illustrated in Figure 5.1. It will be helpful to think of these particles as the atoms making up a continuum body.