1,499 research outputs found

    Organismen von morgen im Experiment von heute – experimentelle Evolution mit Phytoplankton

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    Der globale Wandel erfasst zunehmend auch die Weltmeere und ihre Lebewelt. Insbesondere ErwΓ€rmung und Ozeanversauerung kΓΆnnte den Beginn der Nahrungskette beeintrΓ€chtigen, die mikroskopisch kleinen Pflanzen des Phytoplanktons. Diese Einzeller tragen zur HΓ€lfte der gesamten Biomasse - Produktion auf unserem Planeten bei. Das allermeiste Wissen ΓΌber ihre Reaktionen auf die globalen UmweltverΓ€nderungen hat die Meeresbiologie aus Kurzzeit-Experimenten. Doch die Organismen von morgen kΓΆnnten auch ganz anders auf die neuen Bedingungen reagieren, sofern sie sich evolutiv anpassen. Der Vortrag stellt den neuen Ansatz von Evolutionsexperimenten in der Meereskunde vor. Dieser ermΓΆglicht es, die Organismen von morgen heute im Labor zu untersuchen. Wie erwartet kΓΆnnen sich einige Arten rechtzeitig anpassen, ihre Anpassungsrate ist dabei schneller als die prognostizierten UmweltΓ€nderungen. In einem Ausblick werden die evolutionsbiologischen Konzepte auch auf andere Bereiche in der Meeresbiologie ΓΌbertragen wie die Fischerei

    1. Wochenbericht AL509

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    Wochenbericht FS Alkor Reise 509, Fahrtabschnitt 15.05 – 20.05.201

    Impurity effects in few-electron quantum dots: Incipient Wigner molecule regime

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    Numerically exact path-integral Monte Carlo data are presented for N≀10N\leq 10 strongly interacting electrons confined in a 2D parabolic quantum dot, including a defect to break rotational symmetry. Low densities are studied, where an incipient Wigner molecule forms. A single impurity is found to cause drastic effects: (1) The standard shell-filling sequence with magic numbers N=4,6,9N=4,6,9, corresponding to peaks in the addition energy Ξ”(N)\Delta(N), is destroyed, with a new peak at N=8, (2) spin gaps decrease, (3) for N=8, sub-Hund's rule spin S=0 is induced, and (4) spatial ordering of the electrons becomes rather sensitive to spin. We also comment on the recently observed bunching phenomenon.Comment: 7 pages, 1 table, 4 figures, accepted for publication in Europhysics Letter

    Spatial variability of climate and past atmospheric circulation patterns from central West Antarctic glaciochemistry

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    Atmospheric circulation patterns and the spatial variability of atmospheric chemistry and moisture transport in central West Antarctica are investigated using new 40 year long (1954–1994 A.D.) glaciochemical and accumulation rate records developed from four firn cores from this region. The core sites lie on a 200 km traverse from 82Β° 22β€² S, 119Β° 17β€² W to 81Β° 22β€² S, 107Β° 17β€² W. The glaciochemical records represent the major ionic species present in Antarctic snow: Na+, K+, Mg2+, Ca2+, Clβˆ’, NO3βˆ’, and SO42βˆ’. High spatial variability appears in comparisons of full record averages and poor intersite linear correlation results. Accumulation rates show 50–100% changes over distances of 50–100 km and sea‐salt concentrations drop by 50% between the middle two sites. One likely contributor to the high variability seen at this spatial scale is variability in synoptic‐ and finer‐scale meteorology. Empirical orthogonal function (EOF) analysis shows that 80% or more of the variance in site chemistry can be attributed to two types of air masses: winter season air (50–70% of site variance) with a strong marine signature (heavy loading of sea‐salt species) and summer season air (21% of the variance), marked by marine biogenic non‐sea‐salt SO4 plus NO3. This pattern of winter and summer regimes appears at other West Antarctic sites suggesting it may apply to the entire region. We show that a general picture of the patterns of variability in West Antarctica can best be drawn by using an analysis technique that fully exploits high resolution, multiparameter, multisite data sets

    North Atlantic climate variability from a self-organizing map perspective

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    [1] North Atlantic variability in general, and the North Atlantic Oscillation (NAO) in particular, is a long-studied, very important but still not well-understood problem in climatology. The recent trend to a higher wintertime NAO index was accompanied by an additional increase in the Azores High not coupled to changes in the Icelandic Low, as shown by a self-organizing maps (SOMs) analysis of monthly mean DJF mean sea level pressure data from 1957 to 2002. SOMs are a nonlinear tool to optimally extract a user-specified number of patterns or icons from an input data set and to uniquely relate any input data field to an icon, allowing analyses of occurrence frequencies and transitions complementary to principal component analysis (PCA). SOMs analysis of ERA-40 data finds a North Atlantic monopole roughly colocated with the mean position of the Azores High, as well as the well-known NAO dipole involving the Icelandic Low and the subtropical high. Little trend is shown in December, but the Azores High increased along with the NAO in January and February over the study interval, with implications for storminess in northwestern Europe. In short, our SOM-based analyses of winter MSLP have both confirmed prior knowledge and expanded it through the relative ease of use and power with nonlinear systems of the SOM-based approach to climatological analysis

    Exact broken-symmetry states and Hartree-Fock solutions for quantum dots at high magnetic fields

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    Wigner molecules formed at high magnetic fields in circular and elliptic quantum dots are studied by exact diagonalization (ED) and unrestricted Hartree-Fock (UHF) methods with multicenter basis of displaced lowest Landau level wave functions. The broken symmetry states with semi-classical charge density constructed from superpositions of the ED solutions are compared to the UHF results. UHF overlooks the dependence of the few-electron wave function on the actual relative positions of electrons localized in different charge puddles and partially compensates for this neglect by an exaggerated separation of charge islands which are more strongly localized than in the exact broken-symmetry states.Comment: QD2004 proceedings under press in Physica

    ΠŸΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΠ΅ Ρ€Π°Ρ†ΠΈΠΎΠ½Π°Π»ΡŒΠ½ΠΎΠ³ΠΎ использования чСловСчСского ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»Π°

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    Π Π΅Ρ„Π΅Ρ€Π°Ρ‚ Выпускная квалификационная Ρ€Π°Π±ΠΎΡ‚Π° содСрТит 131 страницу, 20 рисунков, 39 Ρ‚Π°Π±Π»ΠΈΡ†, 50 ΠΈΡΠΏΠΎΠ»ΡŒΠ·ΠΎΠ²Π°Π½Π½Ρ‹Ρ… источников, 6 ΠΏΡ€ΠΈΠ»ΠΎΠΆΠ΅Π½ΠΈΠΉ. ΠšΠ»ΡŽΡ‡Π΅Π²Ρ‹Π΅ слова: пСрсонал, чСловСчСский ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π», Ρ€Π°Ρ†ΠΈΠΎΠ½Π°Π»ΡŒΠ½ΠΎΠ΅ использованиС, адаптация, ΠΊΠΎΠΌΠΏΠ΅Ρ‚Π΅Π½Ρ†ΠΈΠΈ, ПАО «ВРК», ΡΠΎΡ†ΠΈΠ°Π»ΡŒΠ½Π°Ρ ΠΎΡ‚Π²Π΅Ρ‚ΡΡ‚Π²Π΅Π½Π½ΠΎΡΡ‚ΡŒ ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ. . ΠžΠ±ΡŠΠ΅ΠΊΡ‚ΠΎΠΌ исслСдования Π² Ρ€Π°Π±ΠΎΡ‚Π΅ являСтся: Ρ€Π°Ρ†ΠΈΠΎΠ½Π°Π»ΡŒΠ½ΠΎΠ΅ использованиС чСловСчСского ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»Π° ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ. . ЦСль Ρ€Π°Π±ΠΎΡ‚Ρ‹ - рассмотрСниС ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠ² ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΡ Ρ€Π°Ρ†ΠΈΠΎΠ½Π°Π»ΡŒΠ½ΠΎΠ³ΠΎ использования чСловСчСского ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»Π° соврСмСнной ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ . Π’ процСссС исслСдования ΠΏΡ€ΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈΡΡŒ: 1) рассмотрСниС Π΄Π΅ΡΡ‚Π΅Π»ΡŒΠ½ΠΎΡΡ‚ΠΈ ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ Π·Π° 2011 – 2015 Π³Π³.; ΠΎΡ†Π΅Π½ΠΊΠ° Π΄Π΅ΠΉΡΡ‚Π²ΡƒΡŽΡ‰Π΅ΠΉ Π² ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ систСмы управлСния пСрсоналом ΠΈ чСловСчСского ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»Π° ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ; 3) внСсСниС ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΈΠΉ ΠΏΠΎ ΡΠΎΠ²Π΅Ρ€ΡˆΠ΅Π½ΡΡ‚Π²ΠΎΠ²Π°Π½ΠΈΡŽ Π΄Π΅ΠΉΡΡ‚Π²ΡƒΡŽΡ‰Π΅ΠΉ систСмы управлСния чСловСчСским ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»ΠΎΠΌ ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ (с расчСтом экономичСской эффСктивности ΠΎΡ‚ внСсСнных ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΈΠΉ). . Π’ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π΅ исслСдования: внСсСны прСдлоТСния ΠΏΠΎ Π²Π½Π΅Π΄Ρ€Π΅Π½ΠΈΡŽ Π² ΠΊΠ°Π΄Ρ€ΠΎΠ²ΡƒΡŽ Ρ€Π°Π±ΠΎΡ‚Ρƒ систСмы пСриодичСской свСрки ΠΊΠΎΠΌΠΏΠ΅Ρ‚Π΅Π½Ρ†ΠΈΠΉ ΠΈ ΡƒΠ»ΡƒΡ‡ΡˆΠ΅Π½ΠΈΡŽ Ρ€Π°Π±ΠΎΡ‚Ρ‹ с ΠΊΠ°Π΄Ρ€ΠΎΠ²Ρ‹ΠΌ Ρ€Π΅Π·Π΅Ρ€Π²ΠΎΠΌ; ΠΏΡ€ΠΎΠ²Π΅Π΄Π΅Π½ расчСт экономии ΠΎΡ‚ внСдрСния ΠΏΡ€Π΅Π΄Π»Π°Π³Π°Π΅ΠΌΡ‹Ρ… мСроприятий . Π‘Ρ‚Π΅ΠΏΠ΅Π½ΡŒ внСдрСния: Π·Π°ΠΏΠ»Π°Π½ΠΈΡ€ΠΎΠ²Π°Π½ΠΎ ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ внСсСнных ΠΏΠΎ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π°ΠΌ ΠΏΡ€ΠΎΠ²Π΅Π΄Π΅Π½Π½ΠΎΠ³ΠΎ исслСдования ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΈΠΉ Π² Π΄Π΅ΡΡ‚Π΅Π»ΡŒΠ½ΠΎΡΡ‚ΡŒ ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ Π² 2016 Π³. . ΠžΠ±Π»Π°ΡΡ‚ΡŒ примСнСния: ΡƒΠΏΡ€Π°Π²Π»Π΅Π½ΠΈΠ΅ пСрсоналом ΠΈ чСловСчСским ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»ΠΎΠΌ Π² ПАО «ВРК». . ЭкономичСская ΡΡ„Ρ„Π΅ΠΊΡ‚ΠΈΠ²Π½ΠΎΡΡ‚ΡŒ/ Π·Π½Π°Ρ‡ΠΈΠΌΠΎΡΡ‚ΡŒ Ρ€Π°Π±ΠΎΡ‚Ρ‹: сумма ΠΏΠΎΠ»ΡƒΡ‡Π΅Π½Π½ΠΎΠΉ экономии составит 4 165 тыс. Ρ€ΡƒΠ±. Π² Π³ΠΎΠ΄. . Π’ Π±ΡƒΠ΄ΡƒΡ‰Π΅ΠΌ планируСтся: ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ внСсСнных ΠΏΠΎ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π°ΠΌ ΠΏΡ€ΠΎΠ²Π΅Π΄Π΅Π½Π½ΠΎΠ³ΠΎ исслСдования ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΈΠΉ Π² Π΄Π΅ΡΡ‚Π΅Π»ΡŒΠ½ΠΎΡΡ‚ΡŒ ΠΊΠΎΠΌΠΏΠ°Π½ΠΈΠΈ.abstract Final qualifying work includes 131 page, 20 figures, 39 tables, 50 sources used, 6 applications. Keywords: personnel, human potential, rational use, adaptation, competence, PJSC "TRK" social responsibility of the company. . The object of research is in: the rational use of human resources. . Purpose - to examine the methods of enhancing the rational use of the human potential of the modern company. The study carried out: 1) review of the activities of the company for 2011 - 2015 .; assessment of the current in the company personnel management and human resources of the company; 3) make proposals to improve the existing control system of the human potential of the company (with the calculation of the cost-effectiveness of the proposals). . As a result of the study: made suggestions for the implementation of the personnel working in the periodic verification of competency of the system and improvement of work with the personnel reserve; calculated the savings from the implementation of the proposed activities. Degree of implementation: planned application made by the results of the research proposals in the company's activity in 2016. Field of application: personnel management and human potential in PJSC "TRK". . Cost-effectiveness / value of the work: the sum of the savings will amount to 4165 thousand rubles.. in year. . In the future: an application made on the results of the research proposals in the company's activities

    Evaluation of an Electrolyte Analyser for Measurement of Concentrations of Ionized Calcium and Magnesium in Cats

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    The goal of this study was to evaluate the Nova CRT 8 electrolyte analyser for determination of concentrations of ionized calcium (Cai) and magnesium (Mgi) in cats, todetermine the effects of sample handling and storage and to establish reference ranges. The precision and analytical accuracy of the Nova CRT 8 analyser were good. The concentrations of Cai and Mgi were significantly lower in aerobically handled serum samples than in those handled anaerobically. The concentrations of Cai and Mgi differed significantly among whole blood, plasma and serum. In anaerobically handled serum, the concentration of Cai was stable for 8 h at 22Β°C, for 5 days at 4Β°C and for 1 week at βˆ’20Β°C. The concentration of Mgi was stable for 4 h at 22Β°C but for less than 24 h at 4Β°C and for less than 1 week at βˆ’20Β°C. In serum from 36 cats, the reference ranges were 1.20-1.35 mmol/L for Cai and 0.47-0.59 mmol/L for Mgi. The Nova CRT 8 electrolyte analyser is suitable for determination of Cai and Mgi concentrations in cats. Anaerobically handled serum samples are recommended and, stored at room temperature, they yield accurate results when analysed within 4
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