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Basal melt of ice shelves is not only an important part of Antarctica's ice sheet mass budget, but it is also the origin of platelet ice, one of the most distinctive types of sea ice. In many coastal Antarctic regions, ice crystals form and grow in supercooled plumes of Ice Shelf Water. They usually rise towards the surface, becoming trapped under an ice shelf as marine ice or forming a semi-consolidated layer, known as the sub-ice platelet layer, below an overlying sea ice cover. In the latter, sea ice growth consolidates loose crystals to form incorporated platelet ice. These phenomena have numerous and profound impacts on the physical properties, biological processes and biogeochemical cycles associated with Antarctic fast ice: platelet ice contributes to sea ice mass balance and may indicate the extent of ice-shelf basal melting. It can also host a highly productive and uniquely adapted ecosystem. This paper clarifies the terminology and reviews platelet ice formation, observational methods as well as the geographical and seasonal occurrence of this ice type. The physical properties and ecological implications are presented in a way understandable for physicists and biologists alike, thereby providing the background for much needed interdisciplinary research on this topic.
Few studies have derived data-driven dietary patterns in youth in the United States (US). This study examined data-driven dietary patterns and their associations with BMI measures in predominantly low-income, racial/ethnic minority US youth. Data were from baseline assessments of the four Childhood Obesity Prevention and Treatment Research (COPTR) Consortium trials: NET-Works (N=534; 2–4-year-olds), GROW (N=610; 3–5-year-olds), GOALS (N=241; 7–11-year-olds), and IMPACT (N=360; 10–13-year-olds). Weight and height were measured. Children/adult proxies completed 3 24-hour dietary recalls. Dietary patterns were derived for each site from 24 food/beverage groups using k-means cluster analysis. Multivariable linear regression models examined associations of dietary patterns with BMI and percentage of the 95th BMI percentile. Healthy (produce and whole grains) and Unhealthy (fried food, savory snacks, and desserts) patterns were found in NET-Works and GROW. GROW additionally had a dairy and sugar-sweetened beverage based pattern. GOALS had a similar Healthy pattern and a pattern resembling a traditional Mexican diet. Associations between dietary patterns and BMI were only observed in IMPACT. In IMPACT, youth in the Sandwich (cold cuts, refined grains, cheese, and miscellaneous [e.g., condiments]) compared to Mixed (whole grains and desserts) cluster had significantly higher BMI [β=0.99 (95% CI: 0.01, 1.97)] and percentage of the 95th BMI percentile [β=4.17 (95% CI: 0.11, 8.24)]. Healthy and Unhealthy patterns were the most common dietary patterns in COPTR youth, but diets may differ according to age, race/ethnicity, or geographic location. Public health messages focused on healthy dietary substitutions may help youth mimic a dietary pattern associated with lower BMI.
The pharmacotherapy of epilepsy is a complex process guided by evidence-based research and clinical experience. Some patients achieve seizure freedom upon treatment with the first anti-seizure medication (ASM) prescribed, whereas others may be treated with two or three medications before one (or a combination) is found that reduces seizure frequency and/or severity with minimal side effects. Many patients demonstrate a partial response to treatment, leading to reduced seizure frequency and/or severity, but do not become completely seizure free. It is often stated that ~30% of epilepsy patients have seizures that cannot be controlled pharmacologically, and these patients are defined as having medication-resistant epilepsy (MRE). The International League Against Epilepsy (ILAE) published the following definition of MRE: ‘drug resistant epilepsy may be defined as failure of adequate trials of two tolerated and appropriately chosen and used ASM schedules (whether as monotherapies or in combination) to achieve sustained seizure freedom’. Treatment success or sustained seizure freedom is defined as one year without seizures or three times the inter-seizure interval (whichever is longer). The ILAE definition provides a useful standard from which to work, and MRE can be clinically identified in patients that fail to achieve seizure freedom after multiple ASM trials. However, the ILAE definition of successful treatment does not account for partial response to pharmacotherapy. Indeed, many partial responders have improved quality of life, even if they are not seizure-free for one year or more.
Access to cutting-edge technologies is essential for investigators to advance translational research. The Indiana Clinical and Translational Sciences Institute (CTSI) spans three major and preeminent universities, four large academic campuses across the state of Indiana, and is mandate to provide best practices to a whole state.
To address the need to facilitate the availability of innovative technologies to its investigators, the Indiana CTSI implemented the Access Technology Program (ATP). The activities of the ATP, or any program of the Indiana CTSI, are challenged to connect technologies and investigators on the multiple Indiana CTSI campuses by the geographical distances between campuses (1–4 hr driving time).
Herein, we describe the initiatives developed by the ATP to increase the availability of state-of-the-art technologies to its investigators on all Indiana CTSI campuses, and the methods developed by the ATP to bridge the distance between campuses, technologies, and investigators for the advancement of clinical translational research.
The methods and practices described in this publication may inform other approaches to enhance translational research, dissemination, and usage of innovative technologies by translational investigators, especially when distance or multi-campus cultural differences are factors to efficient application.
Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
Trichosporon is a yeast-like basidiomycete, a conditional pathogenic fungus that is rare in the clinic but often causes fatal infections in immunocompromised individuals. Trichosporon asahii is the most common pathogenic fungus in this genus and the occurrence of infections has dramatically increased in recent years. Here, we report a systematic literature review detailing 140 cases of T. asahii infection reported during the past 23 years. Statistical analysis shows that T. asahii infections were most frequently reported within immunodeficient or immunocompromised patients commonly with blood diseases. Antibiotic use, invasive medical equipment and chemotherapy were the leading risk factors for acquiring infection. In vitro susceptibility, clinical information and prognosis analysis showed that voriconazole is the primary drug of choice in the treatment of T. asahii infection. Combination treatment with voriconazole and amphotericin B did not show superiority over either drug alone. Finally, we found that the types of infections prevalent in China are significantly different from those in other countries. These results provide detailed information and relevant clinical treatment strategies for the diagnosis and treatment of T. asahii infection.
Medusahead [Taeniatherum caput-medusae (L.) Nevski] is one of the most detrimental invasive annual grasses impacting the sustainability and function of rangeland in the western United States. This annual grass possesses high concentrations of tissue silicon (Si) that may facilitate invasion through key plant characteristics such as increased plant fitness, structure, and antinutritive qualities. These characteristics may affect known invasive processes such as increased plant productivity, slow litter decomposition, and decreased herbivory, facilitating a positive feedback cycle of invasion. However, Si is not considered an essential element and is often overlooked as a factor of T. caput-medusae invasion. Thus, this article provides a synthesis of plant Si, T. caput-medusae, and the self-reinforcing feedback cycle of invasion. We also discuss how current control strategies address plant characteristics determined by Si and suggest research avenues that may aid in novel or improved control strategies that target the T. caput-medusae–silica relationship.
In response to advancing clinical practice guidelines regarding concussion management, service members, like athletes, complete a baseline assessment prior to participating in high-risk activities. While several studies have established test stability in athletes, no investigation to date has examined the stability of baseline assessment scores in military cadets. The objective of this study was to assess the test–retest reliability of a baseline concussion test battery in cadets at U.S. Service Academies.
All cadets participating in the Concussion Assessment, Research, and Education (CARE) Consortium investigation completed a standard baseline battery that included memory, balance, symptom, and neurocognitive assessments. Annual baseline testing was completed during the first 3 years of the study. A two-way mixed-model analysis of variance (intraclass correlation coefficent (ICC)3,1) and Kappa statistics were used to assess the stability of the metrics at 1-year and 2-year time intervals.
ICC values for the 1-year test interval ranged from 0.28 to 0.67 and from 0.15 to 0.57 for the 2-year interval. Kappa values ranged from 0.16 to 0.21 for the 1-year interval and from 0.29 to 0.31 for the 2-year test interval. Across all measures, the observed effects were small, ranging from 0.01 to 0.44.
This investigation noted less than optimal reliability for the most common concussion baseline assessments. While none of the assessments met or exceeded the accepted clinical threshold, the effect sizes were relatively small suggesting an overlap in performance from year-to-year. As such, baseline assessments beyond the initial evaluation in cadets are not essential but could aid concussion diagnosis.
The crystal structure of oseltamivir phosphate has been refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Oseltamivir phosphate crystallizes in space group P21212 (#18) with a = 24.0079(3), b = 24.6716(2), c = 7.45254(5) Å, V = 4414.24(5) Å3 at 295 K, and Z = 8. Prominent in the crystal structure are hydrogen bonds between the phosphate groups and the ammonium groups of the oseltamivir cations. The strong hydrogen bonds link the cations and the anions into columns parallel to the c-axis, with van der Waals interactions between the columns. Thermal expansion between 120 and 295 K is anisotropic. The powder pattern is included in the Powder Diffraction File™ as entry 00-068-1107.
Introduction: In 2018, Canadian postgraduate specialist Emergency Medicine (EM) programs began implementing a competency-based medical education (CBME) assessment system. To support improvement of this assessment program, we sought to evaluate its short-term educational outcomes nationally and within individual programs. Methods: Program-level data from the 2018 resident cohort were amalgamated and analyzed. The number of Entrustable Professional Activity (EPA) assessments (overall and for each EPA) and the timing of resident promotion through program stages was compared between programs and to the guidelines provided by the national EM specialty committee. Total EPA observations from each program were correlated with the number of EM and pediatric EM rotations. Results: Data from 15 of 17 (88.2%) EM programs containing 9,842 EPA observations from 68 of the 77 (88.3%) Canadian EM specialist residents in the 2018 cohort were analyzed. The average number of EPAs observed per resident in each program varied from 92.5 to 229.6 and correlated strongly with the number of blocks spent on EM and pediatric EM (r = 0.83, p < 0.001). Relative to the guidelines outlined by the specialty committee, residents were promoted later than expected and with fewer EPA observations than suggested. Conclusion: We present a new approach to the amalgamation of national and program-level assessment data. There was demonstrable variation in both EPA-based assessment numbers and promotion timelines between programs and with national guidelines. This evaluation data will inform the revision of local programs and national guidelines and serve as a starting point for further reaching outcome evaluation. This process could be replicated by other national assessment programs.
Les troubles dépressifs concernent près de deux fois plus de femmes que d’hommes . Cette prévalence pourrait être due à une sensibilité accrue des femmes aux émotions négatives . Peu d’études d’imagerie cérébrale ont comparé l’activité cérébrale des hommes et des femmes lors de la présentation de stimuli émotionnels.
Objectif et hypothèse
Notre objectif était d’étudier les activations cérébrales des hommes et des femmes lors d’une tâche émotionnelle. Nous avons émis l’hypothèse que le pattern d’activations cérébrales diffère selon le sexe des individus et la valence des stimuli.
Nous avons mené une étude en imagerie par résonance magnétique fonctionnelle (IRMf) chez 30 participants sains (15 hommes et 15 femmes). Des stimuli à valence positive, négative et neutre étaient présentés aux sujets. Les participants ont évalué subjectivement la valence et l’intensité des stimuli.
Nous observons une activité plus importante chez les femmes que chez les hommes dans plusieurs régions clés du traitement des émotions lors de la présentation de stimuli négatifs. Aucune différence significative entre les hommes et les femmes n’a été relevée concernant l’évaluation subjective des stimuli en termes de valence et d’intensité.
Les résultats suggèrent qu’il existe bien une différence de patterns d’activation entre les hommes et les femmes lors de la perception des émotions négatives, qui irait dans le sens d’une sensibilité accrue chez les femmes. Celle-ci pourrait expliquer leur plus grande vulnérabilité aux troubles dépressifs. Il pourrait être intéressant de répliquer cette étude chez des patients qui souffrent de troubles de l’humeur.
In this study we investigated 1) the changes in anxiety, depression and denial from admission to discharge in patients admitted to the intensive care unit following an acute myocardial infarction and 2) the effect of smoking habits, time lapsed from the appearance of symptoms to seeking help behavior, presence of a person that motivated the patient to seek help, previous myocardial infarction (MI) and family history of MI, on these changes. The results indicated that 1) the levels of both anxiety and depression increased from admission to discharge, while denial decreased; 2) positive family history of MI was associated with lower difference of denial between admission and discharge.
The effect of minor orthopaedic day surgery (MiODS) on patient's mood.
A prospective population-based cohort study of 148 consecutive patients with age above 18 and less than 65, an American Society of Anaesthesiology (ASA) score of 1, and the requirement of General Anaesthesia (GA) were included. The Medical Outcomes Study-Short Form 36 (SF-36), Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) were used pre- and postoperatively.
The mean physical component score of SF-36 before surgery was 45.3 (SD = ±10.1) and 8 weeks following surgery was 44.9 (SD = ±11.04) [n = 148, p = 0.51, 95%CI = (-1.03 -1.52)]. For the measurement of the changes in mood using BDI, BAI and SF-36, latent construct modelling was employed to increase validity. The covariance between mood pre- and post-operatively (cov = 69.44) corresponded to a correlation coefficient, r = 0.88 indicating that patients suffering a greater number of mood symptoms before surgery continue to have a greater number of symptoms following surgery. When the latent mood constructs were permitted to have different means the model fitted well with χ2 (df = 1) = 0.86 for which p = 0.77, thus the null hypothesis that MiODS has no effect on patient mood was rejected.
MiODS affects patient mood which deteriorates at 8 weeks post-operatively regardless of the pre-operative patient mood state. More importantly patients suffering a greater number of mood symptoms before MiODS continue to have a greater number of symptoms following surgery.
Anabolic androgenic steroids (AAS) are derived by chemical manipulation of the testosterone molecule. The specified category of drugs produces anabolic, androgenic and psycho-active effects including elevated aggressive, hostile, violent and anti social behavior.
The objective of this case report observational study was to evaluate the possible psychological consequences of AS use in the twin user of each pair, compared with the non-user twin.
We studied two pairs of male monozygotic twins: one pair 24 years old and the other 31 years old, with absolute genome and phenotype similarity. One of the twins of each pair used AAS while the other did not. Both pairs lived in Hellenic provincial towns and followed a common training and nutrition regime. The psychometric instruments used were the Symptoms Check List-90 (SCL-90) and the Hostility and Direction of Hostility Questionnaire (HDHQ). The psychometric evaluations took place within a time interval of 6 months.
The study found high levels of aggressiveness, hostility, anxiety and paranoid ideation in the twins who used AS. The non-user twins showed no deviation from their initial status.
The use of AAS induced several important psychiatric changes in monozygotic twins which were not present in the twin who did not use AAS.
The objective of our study was to evaluate the psychological consequences of real-world AAS use in athletes abusing such agents, in comparison with a placebo and control group of comparable athletes, while correlating the severity of abuse with the side effects observed. The hypothesis tested by the study was that the use of AAS induces a wide range of psychological side effects whose impact and emergence is dependent upon the severity of the abuse.
The study includes a substantial group of AAS abusing athletes and two more groups demographically similar to the first, one composed of athletes not using any substance and a placebo group. All athletes were stratified according to the severity of AAS abuse. Psychometric instruments were applied to all athletes in specific time intervals, dependent to the AAS abusers' regimens, providing us with a final psychological profile that was to be compared to the pre-study profile. All results were comparable (within and between groups) for statistically significant differences and correlated to the severity of the abuse. Homogeneity of all groups was safeguarded by random doping controls, monitoring of drug levels and analysis of all self obtained drugs by method of liquid chromatography/mass spectrometry. All athletes were provided with a common exercise and dietary regime, so common training and nutritional conditions were achieved.
We studied a cohort of 320 body-building, amateur and recreational athletes, of whom 160 were active users of AAS (group C), 80 users administering placebo drugs (group B) and 80 not abusing any substance (Group A). Group C athletes were stratified according to AAS abuse parameters, thus providing us with three subgroups of “light, medium and heavy abuse”. Athletes of groups A and B were included in a “no abuse” subgroup. The psychometric instruments used were the Symptoms Check List-90 (SCL-90) and the Hostility and Direction of Hostility Questionnaire (HDHQ). The psychometric evaluations took place within a time interval of 13 months. Statistical analysis was performed by using the Mann–Whitney/Wilcoxon two-sample non-parametric test (Kruskal–Wallis test for two groups) for data that were not normally distributed and Linear regression analysis was used to ascertain the correlation between severity of use and escalation of side effects.
The study showed a statistically significant increase in all psychometric subscales recorded in group C, and no statistically significant difference in group C and A. There was a significant increase in the scorings of group C for all subscales of SCL-90 and HDHQ. Correlation of abuse severity and side effects showed that there was a statistical significant increase in Δ values of all SCL-90 and HDHQ subscales that escalated from light abuse to medium and heavy abuse/consumption patterns.
The results of the study suggest that the wide range of psychiatric side effects induced by the use of AAS is correlated to the severity of abuse and the force of these side effects intensifies as the abuse escalates.
People with bipolar disorders may have relapse of mood episodes associated with sleep deprivation and postpartum states. Jet lag can cause sleep problems resulting in relapse of mood episodes in vulnerable people. Melatonin synthesized in the pineal gland will normalize the circadian rhythm and prevent the recurrence of mood episodes in predisposed people. We are reporting a case of successful use of melatonin in a 30-year old lady with history of postpartum onset mood disorder and multiple relapses of mania precipitated by jet lag.
Memory services constitute a significant part of old age psychiatry. Part of the memory assessment includes discussion of driving status as legally there is a requirement to disclose a dementia diagnosis to the DVLA (Driving and Vehicle Licensing Agency). At assessment a driving assessment can be undertaken to establish whether a patient is safe to continue driving.
To establish if discussions regarding driving are taking place in memory assessment clinics, and if available guidance regarding dementia diagnosis and driving are followed. To then re-audit the department following dissemination of results from the initial audit.
Standards set were 100% of patients would have documented discussion of driving. 60 patients were randomly selected from 423 referrals to memory assessment clinic between August 2012 and January 2013. Their electronic records were accessed and audited for evidence regarding documented discussion of driving. The same process was repeated following dissemination of results, with 40 patients records audited between March and May 2014. Data was collected from Bristol Activity of Daily Living Scale (BADLS) and trust pro-forma.
Patients given a diagnosis of mild cognitive impairment were excluded. Of others, 55% of patients in the first audit and 56% of patients in the second audit had documented discussions regarding driving status.
Standards were not met in either audit for a multitude of reasons, including restructuring of services. Recommendations include improvement of information collection tools and further audit, allowing for a longer length of time for implementation of changes.
The crystal structure of atazanavir has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Atazanavir crystallizes in space group P21 (#4) with a = 15.33545(7), b = 5.90396(3), c = 21.56949(13) Å, β = 96.2923(4)°, V = 1941.134(11) Å3, and Z = 2. Despite being labeled as “atazanavir sulfate”, the commercial reagent sample consisted of atazanavir free base. The structure consists of an array of extended-conformation molecules parallel to the ac-plane. Although the atazanavir molecule contains only four classical hydrogen bond donors, hydrogen bonding is, surprisingly, important to the crystal energy. Both intra- and intermolecular hydrogen bonds are significant. The hydroxyl group forms bifurcated intramolecular hydrogen bonds to a carbonyl oxygen atom and an amide nitrogen. Several amide nitrogens act as donors to the hydroxyl group and carbonyl oxygen atoms. An amide nitrogen acts as a donor to another amide nitrogen. Several methyl, methylene, methyne, and phenyl hydrogens participate in hydrogen bonds to carbonyl oxygens, an amide nitrogen, and the pyridine nitrogen. The powder pattern is included in the Powder Diffraction File™ as entry 00-065-1426.
The crystal structure of atorvastatin calcium trihydrate (ACT) has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. ACT crystallizes in space group P1 (#1) with a = 5.44731(4), b = 9.88858(16), c = 29.5925(10) Å, α = 95.859(3), β = 94.211(1), γ = 105.2790(1)°, V = 1521.277(10) Å3, and Z = 1. The most prominent feature of the crystal structure is a hydrophilic layer parallel to the ab-plane. The atorvastatin anions bond to each side of the hydrophilic layer, forming a triple layer. The calcium coordination is distorted octahedral, with the CaO6 coordination sphere being comprised of four carboxylate oxygens, one coordinated water molecule, and a hydroxyl group from one but not the second atorvastatin anion. Several O–H⋯O hydrogen bonds form a two-dimensional network parallel to the ab-plane. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.
Cigarette smoking is strongly associated with major depressive disorder (MDD). However, any genetic etiology of such comorbidity and causal relations is poorly understood, especially at the genome-wide level.
In the present in silico research, we analyzed summary data from the genome-wide association study of the Psychiatric Genetic Consortium for MDD (n = 191 005) and UK Biobank for smoking (n = 337 030) by using various biostatistical methods including Bayesian colocalization analysis, LD score regression, variant effect size correlation analysis, and Mendelian randomization (MR).
By adopting a gene prioritization approach, we identified 43 genes shared by MDD and smoking, which were significantly enriched in membrane potential, gamma-aminobutyric acid receptor activity, and retrograde endocannabinoid signaling pathways, indicating that the comorbid mechanisms are involved in the neurotransmitter system. According to linkage disequilibrium score regression, we found a strong positive correlation between MDD and current smoking (rg = 0.365; p = 7.23 × 10−25) and a negative correlation between MDD and former smoking (rg = −0.298; p = 1.59 × 10−24). MR analysis suggested that genetic liability for depression increased smoking.
These findings inform the concomitant conditions of MDD and smoking and support the use of self-medication with smoking to counteract depression.