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This 29-year-old right-handed woman, diagnosed with schizophrenia at age 21 years, presented with a 3-year history of cognitive decline. Her earliest difficulty was focusing when studying, followed by forgetfulness, both of which affected her performance as a medical student. She ultimately dropped out from school. At the third year of symptoms, her family described her as being disorganized and impulsive. These changes were accompanied by progressive dysarthria and imbalance, with occasional falls.
Audits play a critical role in maintaining the integrity of observational cohort data. While previous work has validated the audit process, sending trained auditors to sites (“travel-audits”) can be costly. We investigate the efficacy of training sites to conduct “self-audits.”
In 2017, eight research groups in the Caribbean, Central, and South America network for HIV Epidemiology each audited a subset of their patient records randomly selected by the data coordinating center at Vanderbilt. Designated investigators at each site compared abstracted research data to the original clinical source documents and captured audit findings electronically. Additionally, two Vanderbilt investigators performed on-site travel-audits at three randomly selected sites (one adult and two pediatric) in late summer 2017.
Self- and travel-auditors, respectively, reported that 93% and 92% of 8919 data entries, captured across 28 unique clinical variables on 65 patients, were entered correctly. Across all entries, 8409 (94%) received the same assessment from self- and travel-auditors (7988 correct and 421 incorrect). Of 421 entries mutually assessed as “incorrect,” 304 (82%) were corrected by both self- and travel-auditors and 250 of these (72%) received the same corrections. Reason for changing antiretroviral therapy (ART) regimen, ART end date, viral load value, CD4%, and HIV diagnosis date had the most mismatched corrections.
With similar overall error rates, findings suggest that data audits conducted by trained local investigators could provide an alternative to on-site audits by external auditors to ensure continued data quality. However, discrepancies observed between corrections illustrate challenges in determining correct values even with audits.
In South-western Atlantic waters, individuals of the southern right whale (SRW) Eubalaena australis spend part of the year (the austral winter and spring) in northern inshore waters where they breed and then migrate to southern feeding grounds during the summer. Mar del Plata (MDP) is located between two main reproductive areas (Península Valdés-Argentina and Santa Catarina-Brazil). The purpose of the present study is to report the presence of SRWs on their journey off the coast of MDP based on sighting records during the past half century. We carried out whale observations through systematic weekly coastal marine mammal surveys in different points of the MDP area from 1966 to 2016. The first SRW sighting was recorded in 1970; since then, sighting frequency has gradually increased, reaching a peak of 28 sightings (N = 63 whales) in 2016. These are unique long-term sighting records of SRWs in Argentina and the first on their journey off the shores of Buenos Aires province. We expect that these results will help local authorities to regulate tourism and other activities in the area and thereby contribute to the conservation of the species.
Although Giardia, the aetiological agent of giardiasis, is one of the most prevalent intestinal parasitic infections world-wide, for industrialised countries, it is mainly appreciated as an imported disease with the minimal local transmission. However, the current evidence challenges this perception; Giardia has relevance beyond the high prevalence areas. This infection may be asymptomatic or cause gastrointestinal complains and long-term sequelae, including irritable bowel syndrome, chronic fatigue and impaired child growth and cognitive development. Its detection and diagnosis present a challenge to physicians who may not be familiar with this infection. To improve interventions to control this parasitosis, it is necessary to maintain a high index of suspicion and remain vigilant in finding cases at risk for infection. A better understanding of the characteristics of populations importing infections alongside improved methods to reliably classify infections as imported or acquired locally will help to ensure early and accurate diagnosis. The evidence shows that public health problems like giardiasis are global issues that need to be addressed collectively by both high and low prevalence countries.
The behavior of Active Regions (ARs) is directly related to the occurrence of some remarkable phenomena in the Sun such as solar flares or coronal mass ejections (CME). In this sense, changes in the magnetic field of the region can be used to uncover other relevant features like the evolution of the ARs magnetic structure and the plasma flow related to it. In this work we describe the evolution of the magnetic structure of the active region AR NOAA12443 observed from 2015/10/30 to 2015/11/10, which may be associated with several X-ray flares of classes C and M. The analysis is based on observations of the solar surface and atmosphere provided by HMI and AIA instruments on board of the SDO spacecraft. In order to investigate the magnetic energy buildup and release of the ARs, we shall employ potential and linear force free extrapolations based on the solar surface magnetic field distribution and the photospheric velocity fields.
An extensive study of the microstructure, nanostructrure and crystallographic properties of six taxa belonging to four different genera of Devonian and Carboniferous Syringoporicae showing dense phaceloid (Pleurosiphonella), pseudocerioid (Neomultithecopora) and cerioid growth patterns (Roemeria and Roemeripora) has been done in order to disclose the similarities and differences in the growth processes at the biomineral scale and understand the growth processes that provide organisms with an evolutionary advantage to colonize different habitats. All the skeletons have similarities regarding the biocrystallization process, showing that the Syringoporicae skeletons are a product of matrix-mediated biocrystallization. Micro- and nanotextural features are common in all of the skeletons studied, showing that they were composed of hierarchical structures. All studied taxa possess a complex nanostructure composed of co-oriented rounded nanocrystals with different sizes and morphologies, depending on the taxon. The identified microstructures include granules, lamellae, fibres and hyaline elements. The crystallographic techniques demonstrate that all of them except the hyaline elements are biogenic in origin. Granules could be aborted fibres during the growth of two corallites in contact. On the other hand, the study of the biomineral properties suggests that the skeleton structure is a reflection of the genetic code. The median lamina was formed by the joint crystallization of both polyps at the same time. The variation in the internal structural organization (phaceloid, pseudocerioid or cerioid) was conditioned by the environment (stressful situations or feeding strategies); on the contrary, the final structure is controlled by genetics and their crystallographic properties are characteristic for each internal structural organization.
We present a set of Molecular Dynamics simulations of the axial elongation of gold nanowires, and the compression of silver decahedral nanowires by a carbon AFM tip. We used Sutton and Chen multibody potentials to describe the metallic interactions, a Tersoff potential to simulate the carbon-carbon interactions, and a 6-12 Lennard-Jones potential to describe the metal-carbon interactions. In the elongation simulations, gold nanowires were subjected to strain at several rates, and we concentrated our attention in the specific case of a wire with an atomistic arrangement based on the intercalation of icosahedral motifs forming a Boerdijk-Coxeter (BCB) spiral, and compare it against results of nanowires with fcc structure and (001), (011), and (111) orientations. We found that the BCB nanowire is more resistant to breakage than the fcc nanowires. In the simulations of lateral compression, we made a strain analysis of the trajectories, finding that when a gold decahedral nanowire is compressed by the AFM tip in a direction parallel to a (100) face, the plastic deformation regime is considerably larger than in the case of compression exerted in a direction parallel to a twin plane, where the fracture of the wire comes almost immediately after the elastic range ends. The strain distribution and elastic response in the compression of nanoparticles with different geometries is also discussed.
A remarkable fossil assemblage composed of five gastropod taxa is described from the Early Miocene of Santa Cruz (Patagonia, Argentina) in southernmost South America. The assemblage includes extinct and living genera South America, and on geographic distributions and represent background new information on spatial and across time distributions as well as identification of new taxa. A new taxon, Patagocharopa enigmatica n. gen. n. sp., is tentatively assigned to Charopidae. Gastrocopta patagonica n. sp. (Vertiginidae) represents the oldest record of Gastrocopta in Argentina and the southernmost record for the Americas. Punctum patagonicum n. sp. (Punctidae) represents the first record of Punctum for continental South America, and characterized by a protoconch with traces of axial costulae and a teleoconch with strong radial ribs. Zilchogyra miocenica n. sp. is the first Miocene record of the charopid genus Zilchogyra. Fragments of a possible Scolodonta (Scolodontidae) are recorded. Overall, the assemblage represents an important and useful paleoenvironmental tool. This fauna suggests that a more temperate and humid environment than today—with a more dense vegetation cover—was prevalent at this site during the Early Miocene.
As a whole neurogenetic diseases are a common group of neurological disorders. However, the recognition and molecular diagnosis of these disorders is not always straightforward. Besides, there is a paucity of information regarding the diagnostic yield that specialized neurogenetic clinics could obtain. We performed a prospective, observational, analytical study of the patients seen in a neurogenetic clinic at a tertiary medical centre to assess the diagnostic yield of a comprehensive diagnostic evaluation that included a personalized clinical assessment along with traditional and next-generation sequencing diagnostic tests. We included a cohort of 387 patients from May 2008 to June 2014. For sub-group analysis we selected a sample of patients whose main complaint was the presence of progressive ataxia, to whom we applied a systematic molecular diagnostic algorithm. Overall, a diagnostic mutation was identified in 27·4% of our cohort. However, if we only considered those patients where a molecular test could be performed, the success rate rises to 45%. We obtained diagnostic yields of 23·5 and 57·5% in the global group of ataxic patients and in the subset of ataxic patients with a positive family history, respectively. Thus, about a third of patients evaluated in a neurogenetic clinic could be successfully diagnosed.
The Mississippian rugose corals from Alabama housed in several museums in that state are revised on the basis of current knowledge of this subclass. Fifteen species belonging to 10 genera have been identified; three species are new, including Zaphrentites lacefieldi, Palastraea cullmanense, and Siphonophyllia alabamaense. Four coral assemblages characterize four stratigraphic subdivisions of the Mississippian in Alabama: Osagean, Meramecian, lower Chesterian, and upper Chesterian. Corals are abundant in some units but diversity is quite low in all assemblages. The level of endemism is very high, except for the lower Chesterian assemblage, which contains some western Paleotethyan forms. Two possible coral evolutionary lineages have been identified.
We approach the analysis of the extent of the projectivity of modules from a fresh perspective as we introduce the notion of relative subprojectivity. A module M is said to be N-subprojective if for every epimorphism g : B → N and homomorphism f : M → N, there exists a homomorphism h : M → B such that gh = f. For a module M, the subprojectivity domain of M is defined to be the collection of all modules N such that M is N-subprojective. We consider, for every ring R, the subprojective profile of R, namely, the class of all subprojectivity domains for R modules. We show that the subprojective profile of R is a semi-lattice, and consider when this structure has coatoms or a smallest element. Modules whose subprojectivity domain is as smallest as possible will be called subprojectively poor (sp-poor) or projectively indigent (p-indigent), and those with co-atomic subprojectivy domain are said to be maximally subprojective. While we do not know if sp-poor modules and maximally subprojective modules exist over every ring, their existence is determined for various families. For example, we determine that artinian serial rings have sp-poor modules and attain the existence of maximally subprojective modules over the integers and for arbitrary V-rings. This work is a natural continuation to recent papers that have embraced the systematic study of the injective, projective and subinjective profiles of rings.
Mortality risk factors have attracted great research interest in recent years. Physical illness is strongly associated with mortality risk in elderly people. Furthermore, a relationship between mortality risk and psychiatric disease in the elderly has gained research interest.
This is a prospective longitudinal multicenter study. A sample of 324 participants was selected as a representative sample of community members aged 65 years and older and living in Huesca (Spain). The following information was collected: affiliation data, severity of physical illness, psychosocial, and psychiatric factors. Statistical analyses were completed with a multivariate analysis in order to control possible confounding variables related to mortality.
Of the initially selected sample, 293 participants were assessed. Sixty-four participants died (21.8%, 95% CI [16.9%, 26.7%]), 5.3% annual rate, and 46.1% showed symptomatology of mental disorders. Older people have eight times greater risk of mortality. The risk increased 53 times in patients affected by several physical illness. No relationship between cognitive dysfunction and depressive symptomatology was observed. In fact, physical condition was associated with depression, and the percentage of participants with depressive symptoms increased according to the severity of physical illness.
Severity of physical illness and age are independently and directly associated with mortality in the elderly people. Therefore, severity of physical illness seems to be a crucial factor in the bi-directional association between mortality and depression, acting as a risk factor independently for both. So the relationship between depression and mortality can be affected by the severity of physical illness.
An effective tagging technique represents a challenge for long-term studies in sea cucumbers. These studies require accurate identification, high tag retention and no adverse effects on vital rates or performance of the tagged individuals. We tested the retention rate of one external and one internal tag in the sea cucumber Holothuria mexicana. The passive integrated transponder (PIT) tag was inserted into the coelomic cavity and the T-bar (external tag) was attached in the upper surface of the body wall. Retention rate was lower, for both kinds of invasive tags, than required in long-term studies. Stress elicited by the tagging procedure caused evisceration of 40% of PIT-tagged individuals versus a 57% of T-bars during or no more than five minutes after tagging. No differences in evisceration between both tags were detected; nor any correlation between evisceration and length. To conclude, the tagging procedure harmed the animals and both PIT-tags and T-bars showed similar low retention rates after ten weeks. Both marks were not effective for long-term studies in Holothuria mexicana.
A recent study by Cid et al. (2012) showed that full halo coronal mass ejections (CMEs) coming from the limb can disturb the terrestrial environment. Although this result seems to rise some controversies with the well established theories, the fact is that the study encourages the scientific community to perform careful multidisciplinary analysis along the Sun-to-Earth chain to fully understand which are the solar triggers of terrestrial disturbances. This paper aims to clarify some of the polemical issues arisen by that paper.
The Cuban Twin Registry is a nation-wide, prospective, population-based twin registry comprising all zygosity types and ages. It was initiated in 2004 to study genetic and environmental contributions to complex diseases with high morbidity and mortality in the Cuban population. The database contains extensive information from 55,400 twin pairs enrolled in the period 2004–2006. Additionally, 2,600 new multiple births have been included from 2007 to date. In the past 4 years, more than 130 studies have been carried out using the registry with a classical genetic epidemiological approach in which concordance rates for monozygotic and dizygotic twins and heritability of various disease traits were estimated. This article summarizes the history, registry's methodology, recent research findings, and future directions of work.
Despite the growing non-medical consumption of amphetamine (Amph) during adolescence, its long-term neurobiological and behavioural effects have remained largely unexplored. The present research sought to characterize the behavioural profile and electrophysiological properties of midbrain monoaminergic neurons in adult rodents after Amph exposure during adolescence. Adolescent rats were administered vehicle, 0.5, 1.5, or 5.0 mg/kg.d Amph from postnatal day (PND) 30–50. At adulthood (PND 70), rats were tested in an open-field test (OFT) and elevated plus maze (EPM), paralleled by in-vivo extracellular recordings of serotonin (5-HT), dopamine (DA) and norepinephrine (NE) neurons from the dorsal raphe nucleus, ventral tegmental area, and locus coeruleus, respectively. 5-HT firing in adulthood was increased in rats that had received Amph (1.5 mg/kg.d) during adolescence. At this regimen, DA firing activity was increased, but not NE firing. Conversely, the highest Amph dose regimen (5.0 mg/kg.d) enhanced NE firing, but not DA or 5-HT firing rates. In the OFT, Amph (1.5 mg/kg.d) significantly increased the total distance travelled, while the other doses were ineffective. In the EPM, all three Amph doses increased time spent in the open arms and central platform, as well as the number of stretch-attend postures made. Repeated adolescent exposure to Amph differentially augments monoaminergic neuronal firing in a dose-specific fashion in adulthood, with corresponding alterations in locomotion, risk assessment (stretch-attend postures and central platform occupancy) and risk-taking behaviours (open-arm exploration). Thus, adolescent Amph exposure induces long-lasting neurophysiological alterations that may have implications for drug-seeking behaviour in the future.
In this study we present an experiment investigating the reconfiguration process elicited by the task switching paradigm in synaesthesia. We study the time course of the operations involved in the activation of photisms. In the experimental Group, four digit-color synaesthetes alternated between an odd-even task and a color task (to indicate the photism elicited by each digit). In both tasks, the target stimuli were numbers between 1 and 9 written in white. One of the control groups ran the same tasks but this time with colored numbers (Naïve Control Group). The results of these studies showed the expected pattern for the control group in the case of regular shift: a significant task switch cost with an abrupt offset and a cost reduction in long RSI. However for the experimental group, we found switch cost asymmetry in the short RSI and non-significant cost in the long RSI. A second control group performed exactly the same tasks as the experimental group (with white numbers as targets and a second imaginary color task) -Trained Control Group-. We found no cost for this second control group. This means that the cost of mental set reconfiguration between numbers (inducers) and their photisms (concurrent sensations) occurs, that there is a specific cost asymmetry (from photisms to inducers) and that this cost cannot be explained by associative learning. The results are discussed in terms of exogenous and endogenous components of mental set reconfiguration.