Влияние неоднородностей температуры поверхности на теплообмен воздуха с Землей

В работе проведено моделирование процесса натекания воздуха с холодной поверхности воды на теплую поверхность суши и сравнение расчетов с результатами измерений. Из расчетов следует, что потоки тепла в прибрежной зоне могут более чем на 20% превышать значения потоков тепла, вычисленных из предположения о горизонтальной однородности приземного слоя. Таким образом, горизонтальную неоднородность атмосферы следует учитывать при расчетах охлаждения водоемов, горизонтальный размер которых имеет масштаб ~100 м.В роботі проведено моделювання процесу натікання повітря з холодної поверхні води на теплу поверхню суші та порівняння розрахунків із вимірюваннями. З розрахунків видно, що потоки тепла в прибережній зоні можуть більш ніж на 20% перевищувати значення потоків тепла, обчислених з припущення про горизонтальну однорідність приземного шару. Таким чином, горизонтальну неоднорідність атмосфери слід враховувати при розрахунках охолодження водойм, горизонтальний розмір яких має масштаб ~100 м.In the paper, the air flow process from the cold water surface onto the warm land surface was simulated. The comparisons of calculations with measurements were performed as well. The calculations show that the heat flux in the narrow coastal zone may be more than 20% higher than the values of heat fluxes calculated from the assumption of horizontal homogeneity of the surface layer. Thus, the horizontal inhomogeneity of the atmosphere must be taken into account in the calculation of the cooling water, the horizontal size of which has a scale of ~100 m

Depth Distribution of Magnetofossils in Near-Surface Sediments From the Blake/Bahama Outer Ridge, Western North Atlantic Ocean, Determined by Low-Temperature Magnetism

Fe-oxide and Fe-sulfide trace minerals in sediments and sedimentary rocks provide proxy records of biogeochemical processes, record past variations in the geomagnetic field, and can serve as proxies for climatic variations. An important class of these Feoxides is produced by bacteria. Magnetic particles produced by magnetotactic bacteria have been proposed as a primary recorder of the geomagnetic field in many terrestrial marine sediments, and have also been suggested to represent fossil evidence of life on the planet Mars. To better understand their distribution and preservation in the sediment column, and their relationship to other biochemical processes, we present rock-magnetic data that document the occurrence and abundance of fossil biogenic magnetite (magnetofossils) in marine sediments from the Blake/Bahama Outer Ridge. Magnetic hysteresis and low-temperature magnetism both indicate that the occurrence of magnetofossils is closely linked to the depth of the modern Fe-redox boundary within the sediment column, and that a fraction of the magnetic minerals in the sediment column above the Fe-redox boundary are in the form of intact and relatively unaltered chains of nanophase magnetite crystals. Below the Fe-redox boundary the abundance of these magnetofossils is markedly decreased. The important conclusions of this work are to demonstrate that nondestructive rock-magnetic methods can be used to successfully document the occurrence and relative abundance of magnetofossils in geologic materials

Phase Splitting for Periodic Lie Systems

In the context of the Floquet theory, using a variation of parameter argument, we show that the logarithm of the monodromy of a real periodic Lie system with appropriate properties admits a splitting into two parts, called dynamic and geometric phases. The dynamic phase is intrinsic and linked to the Hamiltonian of a periodic linear Euler system on the co-algebra. The geometric phase is represented as a surface integral of the symplectic form of a co-adjoint orbit.Comment: (v1) 15 pages. (v2) 16 pages. Some typos corrected. References and further comments added. Final version to appear in J. Phys. A

Granulosa Cell Proliferation is Inhibited by PGE2 in the Primate Ovulatory Follicle

Prostaglandin E2 (PGE2) is a key paracrine mediator of ovulation. Few specific PGE2-regulated gene products have been identified, so we hypothesized that PGE2 may regulate the expression and/or activity of a network of proteins to promote ovulation. To test this concept, Ingenuity Pathway Analysis (IPA) was used to predict PGE2-regulated functionalities in the primate ovulatory follicle. Cynomolgus macaques underwent ovarian stimulation. Follicular granulosa cells were obtained before (0 h) or 36 h after an ovulatory dose of human chorionic gonadotropin (hCG), with ovulation anticipated 37-40 h after hCG. Granulosa cells were obtained from additional monkeys 36 h after treatment with hCG and the PTGS2 inhibitor celecoxib, which significantly reduced hCG-stimulated follicular prostaglandin synthesis. Granulosa cell RNA expression was determined by microarray and analyzed using IPA. No granulosa cell mRNAs were identified as being significantly up-regulated or down-regulated by hCG + celecoxib compared with hCG only. However, IPA predicted that prostaglandin depletion significantly regulated several functional pathways. Cell cycle/cell proliferation was selected for further study because decreased granulosa cell proliferation is known to be necessary for ovulation and formation of a fully-functional corpus luteum. Prospective in vivo and in vitro experiments confirmed the prediction that hCG-stimulated cessation of granulosa cell proliferation is mediated via PGE2. Our studies indicate that PGE2 provides critical regulation of granulosa cell proliferation through mechanisms that do not involve significant regulation of mRNA levels of key cell cycle regulators. Pathway analysis correctly predicted that PGE2 serves as a paracrine mediator of this important transition in ovarian structure and function

A Web-Based, Positive Emotion Skills Intervention for Enhancing Posttreatment Psychological Well-Being in Young Adult Cancer Survivors (EMPOWER): Protocol for a Single-Arm Feasibility Trial

BACKGROUND: Adolescent and young adult cancer survivors (AYAs) experience clinically significant distress and have limited access to supportive care services. Interventions to enhance psychological well-being have improved positive affect and reduced depression in clinical and healthy populations but have not been routinely tested in AYAs. OBJECTIVE: The aim of this protocol is to (1) test the feasibility and acceptability of a Web-based positive emotion skills intervention for posttreatment AYAs called Enhancing Management of Psychological Outcomes With Emotion Regulation (EMPOWER) and (2) examine proof of concept for reducing psychological distress and enhancing psychological well-being. METHODS: The intervention development and testing are taking place in 3 phases. In phase 1, we adapted the content of an existing, Web-based positive emotion intervention so that it would be suitable for AYAs. EMPOWER targets 8 skills (noticing positive events, capitalizing, gratitude, mindfulness, positive reappraisal, goal setting, personal strengths, and acts of kindness) and is delivered remotely as a 5-week, Web-based intervention. Phase 2 consisted of a pilot test of EMPOWER in a single-arm trial to evaluate feasibility, acceptability, retention, and adherence and to collect data on psychosocial outcomes for proof of concept. In phase 3, we are refining study procedures and conducting a second pilot test. RESULTS: The project was part of a career development award. Pilot work began in June 2015, and data collection was completed in March 2019. The analysis is ongoing, and results will be submitted for publication by May 2020. CONCLUSIONS: If this intervention proves feasible and acceptable, EMPOWER will be primed for a subsequent large, multisite randomized controlled trial. As a scalable intervention, it will be ideally suited for AYA survivors who would otherwise not have access to supportive care interventions to help manage posttreatment distress and enhance well-being. TRIAL REGISTRATION: ClinicalTrials.gov NCT02832154, https://clinicaltrials.gov/ct2/show/NCT02832154. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/1707

Short time evolved wave functions for solving quantum many-body problems

The exact ground state of a strongly interacting quantum many-body system can be obtained by evolving a trial state with finite overlap with the ground state to infinite imaginary time. In this work, we use a newly discovered fourth order positive factorization scheme which requires knowing both the potential and its gradients. We show that the resultaing fourth order wave function alone, without further iterations, gives an excellent description of strongly interacting quantum systems such as liquid 4He, comparable to the best variational results in the literature.Comment: 5 pages, 3 figures, 1 tabl

Coherently Controlled Nanoscale Molecular Deposition

Quantum interference effects are shown to provide a means of controlling and enhancing the focusing a collimated neutral molecular beam onto a surface. The nature of the aperiodic pattern formed can be altered by varying laser field characteristics and the system geometry.Comment: 13 pages (inculding 4 figures), LaTeX (Phys. Rev. Lett., 2000, in Press

Genetic basis of octanoic acid resistance in Drosophila sechellia: functional analysis of a fine‐mapped region

Drosophila sechellia is a species of fruit fly endemic to the Seychelles islands. Unlike its generalist sister species, D. sechellia has evolved to be a specialist on the host plant Morinda citrifolia. This specialization is interesting because the plant’s fruit contains secondary defence compounds, primarily octanoic acid (OA), that are lethal to most other Drosophilids. Although ecological and behavioural adaptations to this toxic fruit are known, the genetic basis for evolutionary changes in OA resistance is not. Prior work showed that a genomic region on chromosome 3R containing 18 genes has the greatest contribution to differences in OA resistance between D. sechellia and D. simulans. To determine which gene(s) in this region might be involved in the evolutionary change in OA resistance, we knocked down expression of each gene in this region in D. melanogaster with RNA interference (RNAi) (i) ubiquitously throughout development, (ii) during only the adult stage and (iii) within specific tissues. We identified three neighbouring genes in the Osiris family, Osiris 6 (Osi6), Osi7 and Osi8, that led to decreased OA resistance when ubiquitously knocked down. Tissue‐specific RNAi, however, showed that decreasing expression of Osi6 and Osi7 specifically in the fat body and/or salivary glands increased OA resistance. Gene expression analyses of Osi6 and Osi7 revealed that while standing levels of expression are higher in D. sechellia, Osi6 expression is significantly downregulated in salivary glands in response to OA exposure, suggesting that evolved tissue‐specific environmental plasticity of Osi6 expression may be responsible for OA resistance in D. sechellia.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136293/1/mec14001_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136293/2/mec14001.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136293/3/mec14001-sup-0001-SupInfo.pd