78 research outputs found

    Design of ultra-swollen lipidic mesophases for the crystallization of membrane proteins with large extracellular domains

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    In meso crystallization of membrane proteins from lipidic mesophases is central to protein structural biology but limited to membrane proteins with small extracellular domains (ECDs), comparable to the water channels (3-5 nm) of the mesophase. Here we present a strategy expanding the scope of in meso crystallization to membrane proteins with very large ECDs. We combine monoacylglycerols and phospholipids to design thermodynamically stable ultra-swollen bicontinuous cubic phases of double-gyroid (Ia3d), double-diamond (Pn3m), and double-primitive (Im3m) space groups, with water channels five times larger than traditional lipidic mesophases, and showing re-entrant behavior upon increasing hydration, of sequences Ia3d?Pn3m?Ia3d and Pn3m?Im3m?Pn3m, unknown in lipid self-assembly. We use these mesophases to crystallize membrane proteins with ECDs inaccessible to conventional in meso crystallization, demonstrating the methodology on the Gloeobacter ligand-gated ion channel (GLIC) protein, and show substantial modulation of packing, molecular contacts and activation state of the ensued proteins crystals, illuminating a general strategy in protein structural biology

    Strong damping of phononic heat current by magnetic excitations in SrCu_2(BO_3)_2

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    Measurements of the thermal conductivity as a function of temperature and magnetic field in the 2D dimer spin system SrCu2_2(BO3_3)2_2 are presented. In zero magnetic field the thermal conductivity along and perpendicular to the magnetic planes shows a pronounced double-peak structure as a function of temperature. The low-temperature maximum is drastically suppressed with increasing magnetic field. Our quantitative analysis reveals that the heat current is due to phonons and that the double-peak structure arises from pronounced resonant scattering of phonons by magnetic excitations.Comment: a bit more than 4 pages, 2 figures included; minor changes to improve the clarity of the presentatio

    Emotional intelligence and group cohesion in adolescents

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    Известно, что эмоциональный интеллект является важным фактором адаптации подростка в социальном окружении. Его низкий уровень затрудняет общение, провоцируя не только конфликты и изоляцию подростка, но и агрессию, направленную на нанесение вреда сверстнику. Поэтому именно в подростковый период, по данным исследований, возникает самое большое количество случаев буллинга в школах. Но каким образом связаны эмоциональный интеллект и групповая сплоченность у подростков? В современной литературе до сих пор нет однозначного ответа на этот вопрос. В статье предпринята попытка найти на него ответ.It is a generally accepted fact that emotional intelligence is an important factor in the adaptation of a teenager in a social environment. Its low level makes communication difficult, provoking not only conflicts and isolation of the teenager, but also aggression aimed at harming a peer. Therefore, it is during the teenage period, according to research, that the largest number of cases of bullying occurs in schools. But how are emotional intelligence and group cohesion related in adolescents? In modern literature, there is still no clear answer to this question. The article attempts to find an answer to it

    Neurostimulatory and ablative treatment options in major depressive disorder: a systematic review

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    Introduction Major depressive disorder is one of the most disabling and common diagnoses amongst psychiatric disorders, with a current worldwide prevalence of 5-10% of the general population and up to 20-25% for the lifetime period. Historical perspective Nowadays, conventional treatment includes psychotherapy and pharmacotherapy; however, more than 60% of the treated patients respond unsatisfactorily, and almost one fifth becomes refractory to these therapies at long-term follow-up. Nonpharmacological techniques Growing social incapacity and economic burdens make the medical community strive for better therapies, with fewer complications. Various nonpharmacological techniques like electroconvulsive therapy, vagus nerve stimulation, transcranial magnetic stimulation, lesion surgery, and deep brain stimulation have been developed for this purpose. Discussion We reviewed the literature from the beginning of the twentieth century until July 2009 and described the early clinical effects and main reported complications of these methods. © The Author(s) 2010.Link_to_subscribed_fulltex
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