Cooling in a Bistable Optical Cavity

We propose a generic approach to nonresonant laser cooling of atoms/molecules in a bistable optical cavity. The method exemplifies a photonic version of Sisyphus cooling, in which the matter-dressed cavity extracts energy from the particles and discharges it to the external field as a result of sudden transitions between two stable states

Влияние свойств наполнителей оксидов металлов на динамико-механические характеристики мезокомпозитов, сформированных в постоянных физических полях

Проблематика. Останнім досягненням у галузі матеріалознавства для поліпшення фізико-хімічних властивостей стало використання фізичної модифікації полімерних матеріалів. Особливу увагу дослідників привертає обробка зовнішнім постійним магнітним або електричним полем полімерних матеріалів під час тверднення. Мета дослідження. Визначити вплив властивостей різних за природою оксидів металів на динаміко-механічні характеристики мезокомпозитів. Методика реалізації. Методом динаміко-механічного аналізу було проведено дослідження зразків мезокомпозитів наповнених оксидами металів, які піддані твердненню при дії фізичних полів. Результати дослідження. Орієнтаційний вплив фізичних полів змінює континуум молекул, що беруть участь у реакції поліприєднання та при формуванні певної структури епоксидного полімеру, і зумовлює зростання його вільного об’єму. Набута відмінність модулів еластичності зберігається в інтервалі температур 293–340 К, а при збільшенні температури, внаслідок переходу епоксидного полімеру до високоеластичного стану, орієнтаційні впливи фізичних полів втрачаються. Зразки, сформовані під впливом фізичних полів, характеризуються значно більшими величинами модуля еластичності порівняно зі зразками, сформованими за нормальних умов. Температурні залежності модулів втрат епоксидного полімеру та композитів наповнених оксидами металів, що піддані твердненню за різних умов, збігаються. Висновки. Показано раціональність залучення кислотно-основних властивостей до спрямованої модифікації кристалічної структури, теплофізичних, діелектричних та динаміко-механічних властивостей мезокомпозитів.Background. The latest development in the field of materials to improve the physical and chemical properties is the use of physical modification of polymeric materials. Special attention attracts treatment of external constant magnetic or electric fields of polymeric materials during curing. Objective. To determine the effects of different natural properties of metal oxides on dynamic mechanical properties of mezocomposites. Methods. By dynamic mechanical analysis method study of mezocomposite samples filled with oxides of metals, cured by the action of physical fields was conducted. Results. Orientation influence of physical fields changes continuum of molecules involved in the reaction of polyaddition and in the formation of epoxy polymer structure, and leads to the growth of its free volume. Acquired elasticity modulus difference is stored in the temperature range of 293—340 K, and when the temperature increases, due to the transition to highly polyepoxy state, the orientation influences of physical fields are lost. Samples were formed under the influence of physical fields are characterized by much higherelasticity modulus values compared with samples formed under normal conditions. Temperature dependence modules losses of epoxy polymer and composites filled with oxides of metals cured under different conditions coincide. Conclusions. Rationality involvement of acid-base properties to crystal structure aimed modification, thermophysical, dielectric and dynamic mechanical properties of mezocomposites is shown.Проблематика. Последним достижениям в области материаловедения для улучшения физико-химических свойств стало использование физической модификации полимерных материалов. Особое внимание исследователей привлекает обработка внешним постоянным магнитным или электрическим полем полимерных материалов при отверждении. Цель исследования. Определить влияние свойств различных по природе оксидов металлов на динамико-механические характеристики мезокомпозитов. Методика реализации. Методом динамического механического анализа было проведено исследование образцов мезокомпозитов наполненных оксидами металлов, отвержденных при действии физических полей. Результаты исследования. Ориентационное влияние физических полей меняет континуум молекул, участвующих в реакции полиприсоединения и при формировании определенной структуры эпоксидного полимера, и вызывает рост его свободного объема. Приобретенное отличие модулей эластичности сохраняется в интервале температур 293–340 К, а при увеличении температуры, в результате перехода эпоксидного полимера в высокоэластичное состояние, ориентационные влияния физических полей теряются. Образцы, сформированные под влиянием физических полей, характеризуются значительно большими величинами модуля эластичности по сравнению с образцами, сформированными при нормальных условиях. Температурные зависимости модулей потерь эпоксидного полимера и композитов наполненных оксидами металлов, отвержденных при различных условиях, совпадают. Выводы. Показано рациональность привлечения кислотно-основных свойств к направленной модификации кристаллической структуры, теплофизических, диэлектрических и динамико-механических свойств мезокомпозитов

Cortical Representation of Lateralized Grasping in Chimpanzees (Pan troglodytes): A Combined MRI and PET Study

Functional imaging studies in humans have localized the motor-hand region to a neuroanatomical landmark call the KNOB within the precentral gyrus. It has also been reported that the KNOB is larger in the hemisphere contralateral to an individual's preferred hand, and therefore may represent the neural substrate for handedness. The KNOB has also been neuronatomically described in chimpanzees and other great apes and is similarly associated with handedness. However, whether the chimpanzee KNOB represents the hand region is unclear from the extant literature. Here, we used PET to quantify neural metabolic activity in chimpanzees when engaged in unilateral reach-and-grasping responses and found significantly lateralized activation of the KNOB region in the hemisphere contralateral to the hand used by the chimpanzees. We subsequently constructed a probabilistic map of the KNOB region in chimpanzees in order to assess the overlap in consistency in the anatomical landmarks of the KNOB with the functional maps generated from the PET analysis. We found significant overlap in the anatomical and functional voxels comprising the KNOB region, suggesting that the KNOB does correspond to the hand region in chimpanzees. Lastly, from the probabilistic maps, we compared right- and left-handed chimpanzees on lateralization in grey and white matter within the KNOB region and found that asymmetries in white matter of the KNOB region were larger in the hemisphere contralateral to the preferred hand. These results suggest that neuroanatomical asymmetries in the KNOB likely reflect changes in connectivity in primary motor cortex that are experience dependent in chimpanzees and possibly humans

Joint effects of intensity and duration of cigarette smoking on the risk of head and neck cancer: A bivariate spline model approach

Objectives: This study aimed at re-evaluating the strength and shape of the dose-response relationship between the combined (or joint) effect of intensity and duration of cigarette smoking and the risk of head and neck cancer (HNC). We explored this issue considering bivariate spline models, where smoking intensity and duration were treated as interacting continuous exposures. Materials and Methods: We pooled individual-level data from 33 case-control studies (18,260 HNC cases and 29,844 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium. In bivariate regression spline models, exposures to cigarette smoking intensity and duration (compared with never smokers) were modeled as a linear piecewise function within a logistic regression also including potential confounders. We jointly estimated the optimal knot locations and regression parameters within the Bayesian framework. Results: For oral-cavity/pharyngeal (OCP) cancers, an odds ratio (OR) >5 was reached after 30 years in current smokers of ∼20 or more cigarettes/day. Patterns of OCP cancer risk in current smokers differed across strata of alcohol intensity. For laryngeal cancer, ORs >20 were found for current smokers of ≥20 cigarettes/day for ≥30 years. In former smokers who quit ≥10 years ago, the ORs were approximately halved for OCP cancers, and ∼1/3 for laryngeal cancer, as compared to the same levels of intensity and duration in current smokers. Conclusion: Referring to bivariate spline models, this study better quantified the joint effect of intensity and duration of cigarette smoking on HNC risk, further stressing the need of smoking cessation policies

The pathophysiology of restricted repetitive behavior

Restricted, repetitive behaviors (RRBs) are heterogeneous ranging from stereotypic body movements to rituals to restricted interests. RRBs are most strongly associated with autism but occur in a number of other clinical disorders as well as in typical development. There does not seem to be a category of RRB that is unique or specific to autism and RRB does not seem to be robustly correlated with specific cognitive, sensory or motor abnormalities in autism. Despite its clinical significance, little is known about the pathophysiology of RRB. Both clinical and animal models studies link repetitive behaviors to genetic mutations and a number of specific genetic syndromes have RRBs as part of the clinical phenotype. Genetic risk factors may interact with experiential factors resulting in the extremes in repetitive behavior phenotypic expression that characterize autism. Few studies of individuals with autism have correlated MRI findings and RRBs and no attempt has been made to associate RRB and post-mortem tissue findings. Available clinical and animal models data indicate functional and structural alterations in cortical-basal ganglia circuitry in the expression of RRB, however. Our own studies point to reduced activity of the indirect basal ganglia pathway being associated with high levels of repetitive behavior in an animal model. These findings, if generalizable, suggest specific therapeutic targets. These, and perhaps other, perturbations to cortical basal ganglia circuitry are mediated by specific molecular mechanisms (e.g., altered gene expression) that result in long-term, experience-dependent neuroadaptations that initiate and maintain repetitive behavior. A great deal more research is needed to uncover such mechanisms. Work in areas such as substance abuse, OCD, Tourette syndrome, Parkinson’s disease, and dementias promise to provide findings critical for identifying neurobiological mechanisms relevant to RRB in autism. Moreover, basic research in areas such as birdsong, habit formation, and procedural learning may provide additional, much needed clues. Understanding the pathophysioloy of repetitive behavior will be critical to identifying novel therapeutic targets and strategies for individuals with autism

Genome-wide association analyses identify new susceptibility loci for oral cavity and pharyngeal cancer

We conducted a genome-wide association study of oral cavity and pharyngeal cancer in 6,034 cases and 6,585 controls from Europe, North America and South America. We detected eight significantly associated loci (P < 5 x 10(-8)), seven of which are new for these cancer sites. Oral and pharyngeal cancers combined were associated with loci at 6p21.32 (rs3828805, HLA-DQB1), 10q26.13 (rs201982221, LHPP) and 11p15.4 (rs1453414, OR52N2-TRIM5). Oral cancer was associated with two new regions, 2p23.3 (rs6547741, GPN1) and 9q34.12 (rs928674, LAMC3), and with known cancer-related loci-9p21.3 (rs8181047, CDKN2B-AS1) and 5p15.33 (rs10462706, CLPTM1L). Oropharyngeal cancer associations were limited to the human leukocyte antigen (HLA) region, and classical HLA allele imputation showed a protective association with the class II haplotype HLA-DRB1*1301-HLA-DQA1*0103-HLA-DQB1*0603 (odds ratio (OR) = 0.59, P = 2.7 x 10(-9)). Stratified analyses on a subgroup of oropharyngeal cases with information available on human papillomavirus (HPV) status indicated that this association was considerably stronger in HPV-positive (OR = 0.23, P = 1.6 x 10(-6)) than in HPV-negative (OR = 0.75, P = 0.16) cancers

Lessons learned from the INHANCE consortium: An overview of recent results on head and neck cancer

Objective: To summarize the latest evidence on head and neck cancer epidemiology from the International Head and Neck Cancer Epidemiology (INHANCE) consortium. Subjects and Methods: INHANCE was established in 2004 to elucidate the etiology of head and neck cancer through pooled analyses of individual-level data on a large scale. We summarize results from recent INHANCE-based publications updating our 2015 overview. Results: Seventeen papers were published between 2015 and May 2020. These studies further define the nature of risks associated with tobacco and alcohol, and occupational exposures on head and neck cancer. The beneficial effects on incidence of head and neck cancer were identified for good oral health, endogenous and exogenous hormonal factors, and selected aspects of diet related to fruit and vegetables. INHANCE has begun to develop risk prediction models and to pool follow-up data on their studies, finding that ~30% of cases had cancer recurrence and 9% second primary cancers, with overall- and disease-specific 5-year-survival of 51% and 57%, respectively. Conclusions: The number and importance of INHANCE scientific findings provides further evidence of the advantages of large-scale internationally collaborative projects and will support the development of prevention strategies