The Impact of an Evidence-Based Medicine Workshop on Residents’ Attitudes towards and Self-Reported Ability in Evidence-Based Practice

Background: Evidence-based medicine (EBM) is a part of many medical school and residency curricula worldwide, but there is little research into the most effective methods to teach these skills. Purpose: To evaluate whether a course on EBM utilizing adult learning principals leads to both immediate and short-term attitudinal, confidence, and behavioral change. Methods: Seventy-three (73) Internal Medicine and Internal Medicine/Pediatric residents attended a half-day seminar on EBM. Participants completed pre- and post-course 5-point Likert questionnaires, and set two personal goals for integrating EBM into their daily practice. We performed nonparametric two-sample Wilcoxon Rank-Sum tests to compare responses. We also elicited the self-reported success of the residents in meeting their goals one-month post-course. Results: Attitudes about EBM improved (3.5 pre-course vs. 3.7 post-course), as well as self-reported EBM skills (3.0 vs. 3.3). Seventy-two percent of residents reported having met at least one of their two goals for the integration of EBM into their practice. Conclusions: An EBM workshop based upon adult learning principles was successful in meeting multiple educational goals. The links between andragogy, learners’ internal drive for behavior change, and successful EBM education should be further explored

Orthotic management of cerebral palsy : recommendations from a consensus conference

An international multidisciplinary group of healthcare professionals and researchers participated in a consensus conference on the management of cerebral palsy, convened by the International Society for Prosthetics and Orthotics. Participants reviewed the evidence and considered contemporary thinking on a range of treatment options including physical and occupational therapy, and medical, surgical and orthotic interventions. The quality of many of the reviewed papers was compromised by inadequate reporting and lack of transparency, in particular regarding the types of patients and the design of the interventions being evaluated. Substantial evidence suggests that ankle-foot orthoses (AFOs) that control the foot and ankle in stance and swing phases can improve gait efficiency in ambulant children (GMFCS levels I-III). By contrast, little high quality evidence exists to support the use of orthoses for the hip, spine or upper limb. Where the evidence for orthosis use was not compelling consensus was reached on recommendations for orthotic intervention. Subsequent group discussions identified recommendations for future research. The evidence to support using orthoses is generally limited by the brevity of follow-up periods in research studies; hence the extent to which orthoses may prevent deformities developing over time remains unclear. The full report of the conference can be accessed free of charge at www.ispoint.org

Polar Bear Distribution and Habitat Association Reflect Long-term Changes in Fall Sea Ice Conditions in the Alaskan Beaufort Sea

The polar bear (Ursus maritimus) is considered an indicator species of ecosystem health because of its longevity, life-history requirements, reliance on sea ice (i.e., sea ice obligate), and position in the Arctic food web. Polar bear distribution and habitat association should both be reliable signals for environmental perturbation, as the bears respond behaviorally to changes in sea ice extent, the timing and duration of ice formation, and ablation. Polar bears and sea ice conditions were monitored as part of the annual fall bowhead whale (Balaena mysticetus) aerial survey in the Alaskan Beaufort Sea between 1979 and 2005. Habitats associated with polar bear sightings changed during the study, with fewer bears associated with ice (irrespective of ice type and percent) and more bears associated with land and open water. Large-scale differences were documented for both ice type and percent ice cover, particularly in September. In general, the pattern in September (and to a lesser extent in October) included a reduction in old ice and a concomitant increase in open water. In addition, there was an eastward and landward shift in polar bear sightings. From 1979 to 1987, polar bears were observed primarily on ice along the shelf break near Barrow, whereas from 1997 to 2005, polar bears were observed on barrier islands or along the mainland coast near Kaktovik. The changes in polar bear distribution and habitat association appear to reflect a behavioral response by polar bears to changes in ice (type and percent cover) and in the timing of ice formation and ablation.L’ours polaire (Ursus maritimus) est considéré comme une espèce indicatrice de la santé de l’écosystème en raison de sa longévité, des besoins de son cycle biologique, de sa dépendance de la glace de mer (c’est-à-dire la glace de mer obligatoire) et de la position qu’il occupe dans le réseau alimentaire de l’Arctique. La répartition de l’ours polaire et son association à un habitat devraient tous deux constituer des signaux fiables en matière de perturbation de l’environnement car le comportement des ours varie en fonction des changements caractérisant l’étendue de glace de mer, la synchronisation et la durée de la formation de la glace, de même que l’ablation. Les ours polaires et les conditions de la glace de mer ont fait l’objet d’une surveillance dans le cadre du levé aérien annuel de la baleine boréale (Balaena mysticetus) effectué à l’automne dans la mer de Beaufort alaskienne entre 1979 et 2005. Au cours de l’étude, les habitats liés aux observations d’ours polaires ont évolué, un moins grand nombre d’ours étant associés à la glace (sans égard au type et au pourcentage de glace) et un plus grand nombre d’ours étant associés à la terre et à l’eau libre. Les différences à grande échelle ont été répertoriées tant pour le type de glace que pour le pourcentage de couche de glace, particulièrement en septembre. En général, la tendance en septembre (et en octobre, dans une moindre mesure) comprenait une réduction de l’ancienne glace de même qu’une augmentation concomitante dans l’eau libre. De plus, on a enregistré un décalage vers l’est et vers l’intérieur des terres en ce qui a trait aux observations d’ours polaires. De 1979 à 1987, les ours polaires ont surtout été observés sur la glace le long du rebord continental près de Barrow, tandis que de 1997 à 2005, les ours polaires ont été observés sur les îles-barrières ou le long de la côte continentale près de Kaktovik. Les changements caractérisant la répartition des ours polaires et l’association à un habitat semblent refléter une réaction comportementale des ours polaires vis-à-vis des changements relatifs à la glace (le type et le pourcentage de la couche) ainsi que de la synchronisation de la formation et de l’ablation de la glace

Dissipative Quantum Ising model in a cold atomic spin-boson mixture

Using cold bosonic atoms with two (hyperfine) ground states, we introduce a spin-boson mixture which allows to implement the quantum Ising model in a tunable dissipative environment. The first specie lies in a deep optical lattice with tightly confining wells and forms a spin array; spin-up/down corresponds to occupation by one/no atom at each site. The second specie forms a superfluid reservoir. Different species are coupled coherently via laser transitions and collisions. Whereas the laser coupling mimics a transverse field for the spins, the coupling to the reservoir sound modes induces a ferromagnetic (Ising) coupling as well as dissipation. This gives rise to an order-disorder quantum phase transition where the effect of dissipation can be studied in a controllable manner.Comment: 4 pages, 2 figures, 1 table; Title modified and cosmetic change

Solving the Wolbachia Paradox: Modeling the Tripartite Interaction between Host, Wolbachia, and a Natural Enemy

Wolbachia is one of the most common symbionts of arthropods. Its establishment requires lateral transfer to and successful transmission within novel host species. However, Wolbachia performs poorly when introduced into new host species, and models predict that Wolbachia should seldom be able to establish from low initial frequencies. Recently, various symbionts, including Wolbachia, have been shown to protect their hosts from natural enemies. Hence, Wolbachia invasion may be facilitated by the dynamic interaction between it, its host, and a natural enemy. We model such an interaction whereby Wolbachia induces either complete resistance, partial resistance, or tolerance to a host-specific pathogen and also induces the common manipulation phenotype of cytoplasmic incompatibility (CI). We show that the presence of the pathogen greatly facilitates Wolbachia invasion from rare and widens the parameter space in which "imperfect" Wolbachia strains can invade. Furthermore, positive frequency-dependent selection through CI can drive Wolbachia to very high frequencies, potentially excluding the pathogen. These results may explain a poorly understood aspect of Wolbachia biology: it is widespread, despite performing poorly after transfer to new host species. They also support the intriguing possibility that Wolbachia strains that encode both CI and natural-enemy resistance could potentially rid insects, including human disease vectors, of important pathogens

Traditional Knowledge about Polar Bears (Ursus maritimus) in Northwestern Alaska

Polar bears (Ursus maritimus) are an iconic Arctic species, but residents of Arctic coastal communities are among the few who have opportunities to observe their behavior for extended periods of time. Documenting traditional knowledge about polar bears is thus an important research approach, especially in light of recent rapid changes to summer sea ice extent. We interviewed polar bear hunters in seven Alaska Native communities along the coast of the northern Bering Sea and Chukchi Sea. Our study confirmed findings from similar research conducted in the mid-1990s and added information about the responses of polar bears to more recent environmental change. The distribution and local abundance of polar bears have changed over time, though different communities report different patterns. Polar bears arrive from the north later in fall than previously. Despite substantial changes in sea ice and other aspects of polar bear habitat, the animals generally appear to be in good body condition, and cubs continue to be observed regularly. While polar bears continue to feed primarily on seals, they have been observed eating a diverse range of foods, including eggs, greens, fish, berries, and other foods as available. Reduction in harvest levels due to environmental, economic, and social factors is the overriding trend; however, in years when bears are particularly abundant around villages, this pattern is temporarily reversed. Polar bears remain important spiritually and culturally for the indigenous communities of northern and western Alaska.Les ours polaires (Ursus maritimus) constituent une espèce iconique de l’Arctique, mais les résidents des collectivités côtières de l’Arctique figurent parmi les quelques personnes qui ont l’occasion d’observer leur comportement pendant des périodes prolongées. C’est pourquoi la consignation des connaissances traditionnelles sur les ours polaires représente un aspect important de la recherche, surtout à la lumière des changements rapides caractérisant l’étendue de la glace de mer en été. Nous avons interviewé des chasseurs d’ours polaires de sept collectivités autochtones de l’Alaska situées le long de la côte nord de la mer de Béring et de la mer des Tchouktches. Notre étude a permis de confirmer les observations émanant de travaux de recherche similaires réalisés dans le milieu des années 1990 ainsi que d’enrichir l’information sur la réaction des ours polaires vis-à-vis des changements environnementaux plus récents. La répartition et l’abondance locale d’ours polaires ont changé au fil du temps, bien que les tendances diffèrent d’une collectivité à l’autre. À l’automne, les ours polaires arrivent du Nord plus tard qu’avant. Malgré les importants changements qui caractérisent les glaces de mer et d’autres aspects de l’habitat de l’ours polaire, les animaux semblent généralement en bon état corporel, et l’on continue d’observer des oursons régulièrement. Même si les ours polaires continuent de s’alimenter principalement de phoques, on les a vus en train de manger divers aliments, dont des oeufs, des plantes vertes, du poisson, des petits fruits et d’autre nourriture, selon les disponibilités. Les taux de récolte à la baisse en raison de facteurs environnementaux, économiques et sociaux constituent la tendance prépondérante. Cependant, au cours des années pendant lesquelles les ours sont nombreux autour des villages, cette tendance est renversée temporairement. Par ailleurs, les ours polaires continuent de revêtir une importance spirituelle et culturelle pour les collectivités indigènes du nord et de l’ouest de l’Alaska

Iñupiaq Knowledge of Polar Bears (Ursus maritimus) in the Southern Beaufort Sea, Alaska

Successful wildlife management depends upon coordination and consultation with local communities. However, much of the research used to inform management is often derived solely from data collected directly from wildlife. Indigenous people living in the Arctic have a close connection to their environment, which provides unique opportunities to observe their environment and the ecology of Arctic species. Further, most northern Arctic communities occur within the range of polar bears (nanuq, Ursus maritimus) and have experienced significant climatic changes. Here, we used semi-structured interviews from 2017 to 2019 to document Iñupiaq knowledge of polar bears observed over four decades in four Alaskan communities in the range of the Southern Beaufort Sea polar bear subpopulation: Wainwright, Utqiaġvik, Nuiqsut, and Kaktovik. All but one of 47 participants described directional and notable changes in sea ice, including earlier ice breakup, later ice return, thinner ice, and less multiyear pack ice. These changes corresponded with observations of bears spending more time on land during the late summer and early fall in recent decades—observations consistent with scientific and Indigenous knowledge studies in Alaska, Canada, and Greenland. Participants noted that polar bear and seal body condition and local abundance either varied geographically or exhibited no patterns. However, participants described a recent phenomenon of bears being exhausted and lethargic when arriving on shore in the summer and fall after extensive swims from the pack ice. Further, several participants suggested that maternal denning is occurring more often on land than sea ice. Participants indicated that village and regional governments are increasingly challenged to obtain resources needed to keep their communities safe as polar bears spend more time on land, an issue that is likely to be exacerbated both in this region and elsewhere as sea ice loss continues. La gestion réussie de la faune dépend des efforts de coordination et de consultation avec les collectivités locales. Toutefois, il arrive souvent qu’une grande partie de la recherche utilisée pour éclairer la gestion dérive uniquement des données recueillies directement de la faune. Les peuples autochtones qui vivent dans l’Arctique entretiennent des liens étroits avec leur environnement, ce qui crée des occasions uniques d’observer l’environnement et l’écologie des espèces de l’Arctique. Il y a également lieu de remarquer que la plupart des collectivités du nord de l’Arctique se trouvent dans l’aire de répartition des ours polaires (nanuq, Ursus) et connaissent d’importants changements climatiques. Dans le cadre de cette étude, nous nous sommes appuyés sur des entrevues semi-structurées réalisées entre 2017 et 2019 pour documenter les connaissances des Iñupiaq au sujet des ours polaires découlant d’observations échelonnées sur quatre décennies dans quatre collectivités de l’Alaska situées dans l’aire de répartition de la sous-population d’ours polaires du sud de la mer de Beaufort : Wainwright, Utqiaġvik, Nuiqsut et Kaktovik. Les 47 participants, sauf un, ont décrit des changements directionnels et remarquables en ce qui a trait à la glace de mer, dont des débâcles plus hâtives, le retour plus tardif de la glace, de la glace plus mince et moins de banquises pluriannuelles. Ces changements correspondent aux observations d’ours qui passent plus de temps sur la terre ferme en fin d’été et en début d’automne au cours des dernières décennies. Ces observations coïncident avec les études sur les connaissances scientifiques et autochtones réalisées en Alaska, au Canada et au Groenland. Les participants ont fait remarquer que la condition corporelle des ours polaires et des phoques ainsi que leur abondance à l’échelle locale variaient d’une région à l’autre ou n’affichaient aucune tendance. Cependant, les participants ont décrit un phénomène récent selon lequel les ours sont épuisés et léthargiques lorsqu’ils arrivent sur la rive à l’été et à l’automne, après avoir parcouru de longues distances à la nage depuis les banquises. Aussi, plusieurs participants ont laissé entendre que les aires de mise bas se retrouvent plus souvent sur la terre ferme que sur la glace de mer. Les participants ont indiqué que le gouvernement des villages et les gouvernements régionaux ont de plus en plus de difficulté à obtenir les ressources nécessaires pour assurer la sécurité de leurs collectivités, car les ours polaires passent plus de temps sur la terre ferme, un enjeu qui risque de s’aggraver, tant dans cette région qu’ailleurs, à mesure que la glace de mer continuera de perdre de l’ampleur.

The electron lifetime in Luttinger liquids

We investigate the decoherence of the electron wavepacket in purely ballistic one-dimensional systems described through the Luttinger liquid (LL). At a finite temperature $T$ and long times $t$, we show that the electron Green's function for a fixed wavevector close to one Fermi point decays as $\exp(-t/\tau_F)$, as opposed to the power-law behavior occurring at short times, and the emerging electron lifetime obeys $\tau_F^{-1}\propto T$ for spinful as well as spinless electrons. For strong interactions, $(T\tau_F)\ll 1$, reflecting that the electron is not a good Landau quasiparticle in LLs. We justify that fractionalization is the main source of electron decoherence for spinful as well as spinless electrons clarifying the peculiar electron mass renormalization close to the Fermi points. For spinless electrons and weak interactions, our intuition can be enriched through a diagrammatic approach or Fermi Golden rule and through a Johnson-Nyquist noise picture. We stress that the electron lifetime (and the fractional quasiparticles) can be revealed from Aharonov-Bohm experiments or momentum resolved tunneling. We aim to compare the results with those of spin-incoherent and chiral LLs.Comment: 20 pages, 1 column, 6 figures, 1 Table; expands cond-mat/0110307 and cond-mat/0503652; final version to appear in PR

Time-reversal symmetry breaking in circuit-QED based photon lattices

Breaking time-reversal symmetry is a prerequisite for accessing certain interesting many-body states such as fractional quantum Hall states. For polaritons, charge neutrality prevents magnetic fields from providing a direct symmetry breaking mechanism and similar to the situation in ultracold atomic gases, an effective magnetic field has to be synthesized. We show that in the circuit QED architecture, this can be achieved by inserting simple superconducting circuits into the resonator junctions. In the presence of such coupling elements, constant parallel magnetic and electric fields suffice to break time-reversal symmetry. We support these theoretical predictions with numerical simulations for realistic sample parameters, specify general conditions under which time-reversal is broken, and discuss the application to chiral Fock state transfer, an on-chip circulator, and tunable band structure for the Kagome lattice.Comment: minor revisions, version published in PRA; 19 pages, 13 figures, 2 table

Muscle-Specific Loss of \u3cem\u3eBmal1\u3c/em\u3e Leads to Disrupted Tissue Glucose Metabolism and Systemic Glucose Homeostasis

Background: Diabetes is the seventh leading cause of death in the USA, and disruption of circadian rhythms is gaining recognition as a contributing factor to disease prevalence. This disease is characterized by hyperglycemia and glucose intolerance and symptoms caused by failure to produce and/or respond to insulin. The skeletal muscle is a key insulin-sensitive metabolic tissue, taking up ~80 % of postprandial glucose. To address the role of the skeletal muscle molecular clock to insulin sensitivity and glucose tolerance, we generated an inducible skeletal muscle-specific Bmal1 −/− mouse (iMSBmal1 −/−). Results: Progressive changes in body composition (decreases in percent fat) were seen in the iMSBmal1 −/− mice from 3 to 12 weeks post-treatment as well as glucose intolerance and non-fasting hyperglycemia. Ex vivo analysis of glucose uptake revealed that the extensor digitorum longus (EDL) muscles did not respond to either insulin or 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) stimulation. RT-PCR and Western blot analyses demonstrated a significant decrease in mRNA expression and protein content of the muscle glucose transporter (Glut4). We also found that both mRNA expression and activity of two key rate-limiting enzymes of glycolysis, hexokinase 2 (Hk2) and phosphofructokinase 1 (Pfk1), were significantly reduced in the iMSBmal1 −/− muscle. Lastly, results from metabolomics analyses provided evidence of decreased glycolytic flux and uncovered decreases in some tricarboxylic acid (TCA) intermediates with increases in amino acid levels in the iMSBmal1 −/− muscle. These findings suggest that the muscle is relying predominantly on fat as a fuel with increased protein breakdown to support the TCA cycle. Conclusions: These data support a fundamental role for Bmal1, the endogenous circadian clock, in glucose metabolism in the skeletal muscle. Our findings have implicated altered molecular clock dictating significant changes in altered substrate metabolism in the absence of feeding or activity changes. The changes in body composition in our model also highlight the important role that changes in skeletal muscle carbohydrate, and fat metabolism can play in systemic metabolism