142,994 research outputs found
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
LASERSPECTROSCOPIC INVESTIGATION OF HIGHER EXCITED ELECTRONIC STATES OF KAr
No full textAuthor Institution: Technische Universit\""{a}t Berlin, Institut f\""{u} Strahlungs- und KemphysikFirst successful measurements on higher excited electronic states of the van der Waals molecule KAr have been performed in a supersonic jet. The higher excited electronic stales are reached in a two-step excitation via the intermediate slate using two tunable cw dye lasers. One laser the pump laser with nm, was tuned to a suitable rovibrational line of the transition populating one rovibrational sublevel of the state. The second probe laser ( nm) was scanned over a range at about . By means of a systematic variation of the pumping transition we found a total of more man 500 lines due to the transition . A large part of these lines could be assigned to the rotational structure of vibrational bands leading to vibrational levels of the two states being correlated with the and the stale of the K-atom. In addition, the parameters of rotation and of spin-orbit coupling could be determined for 6 and 3 vibrational levels due to the and the state, respectively For the state an inverted fine structure splitting of around - was observed for ail vibrational stales which is in good agreement with the value predicted from the inverted tine structure splitting of the state of The K atom. Up to now the interatomic potentials of the higher excited slates could not be determined from our spectroscopic results as numerous avoided crossings between different potential curves are expected leading to large deviations from the usual ladder of vibrational energies
Osmanlı Anonim Şirketlerinde Kar Dağıtımı
No full textOsmanlı Devletinin değişim ve modernleşme çabalarının süreci olarak tanımlanan 19.yy ve Tanzimat dönemi uygulamalarında ticari hayata ilişkinde birçok düzenleme ve çalışma var olduğu görülmektedir. Bunların başında düzenleyici otorite olarak Ticaret ve Ziraat Nezareti adı altında bir bakanlığın kurulması gelmiştir. Aynı dönemde, Avrupa ile gelişen ticarette tarafların haklarını yasal bir zeminde arayabilmeleri için batı kaynaklı bir Ticaret Kanunu uygulamaya alınmıştır. Bu kanunda diğer şirket türleri ile birlikte anonim şirketlere de yer verilmiştir. Ancak kanunda anonim şirketlerin faaliyet süreci içersindeki kuruluşları, organları, bunların çalışma prensipleri, kar dağıtımı gibi düzenlemelere yer verilmemiştir. Bu sıkıntılı durum bakanlık tarafından örneği hazırlanan bir nizamname (içtüzük) ile aşılmaya çalışılmıştır. İşte bu çalışmada bu nizamname çerçevesinde faaliyette bulunan osmanlı anonim şirketlerin kar dağıtımına ilişkin düzenlemelerine yer verilmiştir. Benzer şekilde dönemin şirketlerinden yapılan örnekleme ile faaliyet raporlarında bunu nasıl yansıttıkları incelenmiştir
Vitamin D and Female Reproduction
No full textAbsztrakt
Bevezetés: A D-vitamin több, mint egy vitamin, egy szteroid hormon. A klasszikus hatásai mellett egyre több figyelem irányul a nem klasszikus hatásokra, illetve a különböző kórképekben betöltött szerepére. A kalcium és foszfor háztartás mellett hatással van az immunrendszerre, a hormonrendszerre és a reproduktív szervekre egyaránt. A méhre, petefészkekre és terhességre gyakorolt hatása révén fontos szerepet tulajdonítanak neki a reprodukcióban, illetve egyre több tanulmány vizsgálja a D-vitamin hiány és az infertilitás kapcsolatát.
Módszer: A diplomamunka a PubMed és más kisebb adatbázisokban 2022. február 10-ig végzett irodalomkutatáson alapul. A források között található szisztematikus áttekintés, metaanalízis, prospektív és retrospektív vizsgálat egyaránt.
Eredmények: A tanulmányok alapján a D-vitamin kötő fehérje és D-vitamin receptor a női nemi szervek számos sejttípusánál megtalálhatóak. Közvetlenül és közvetve más molekulák szabályozásán keresztül fejti ki hatását az endometriumra, miometriumra, petefészkekre és placentára. A D-vitaminnak szerepe van többek között az AMH és HOXA10 szabályozásában, hatással van a nemi hormonok termelődésére, egyes sejtek hormonok iránti érzékenységére. Hiánya növeli a szülési komplikációk és a magzat rendellenes fejlődésének a kockázatát. Emellett kimutatták a D-vitamin hiány szerepét olyan, sok esetben infertilitást okozó nőgyógyászati kórképek esetében, mint a PCOS, endometriózis, primer dysmneorrhoea, vagy a méh leiomiómája.
Megbeszélés: Bár még nem teljesen tisztázott, az eddigi kutatások alapján kijelenthető, hogy a D-vitaminnak komplex, pozitív hatása van a női reprodukcióra. A D-vitamin pótlása javasolt a meddőség kezelésében, különösen jelentős hiányállapot esetén. Terhesség során is számos pozitív hatásról számoltak be a D-vitamin kapcsán, az azonban még nem egyértelmű, hogy szükséges-e ilyen esetben a D-vitamin rutinszerű pótlása és ha igen, milyen mértékben.általános orvostudományinappalimagyaregységes, osztatla
KAR stimulates ELOVL6 enzyme activity in KAR enzyme activity-independent and -dependent manners.
No full text<p>(A) The yeast TatY56 (<i>ayr1</i>Δ<i>::natNT2 YBR159W-FLAG-AID</i>) cells harboring the pWK40 (2xHA vector), pTN41(<i>2xHA-YBR159w</i>), pTN42 (<i>2xHA-KAR</i>), pTN44 (<i>2xHA-KAR Y202A/K206A</i>), pTN45 (<i>2xHA-KAR S189A</i>), or pTN46 (<i>2xHA-KAR N161A</i>) plasmid were treated with 0.5 mM 3-indolacetic acid for 2 h. Total membrane proteins (20 µg) prepared from them were incubated with 20 µM C16∶0-CoA, 73 µM malonyl-CoA, and 27 µM [<sup>14</sup>C]malonyl-CoA (0.075 µCi) for 30 min at 37°C in the presence of 1 mM NADPH. After termination of the reactions, lipids were saponified, acidified, extracted, converted to methyl ester forms, separated by reverse-phase TLC, and detected by a bioimaging analyzer BAS-2500. (B) Total membrane fractions prepared from HEK 293T cells transfected with the pCE-puro 3xFLAG-KAR or pCE-puro 3xFLAG-KAR S189A plasmid were solubilized with 2% Triton X-100, and subjected to affinity-purification using anti-FLAG M2 agarose affinity beads. Purified proteins (1 µg) were separated by SDS-PAGE and stained with Coomassie brilliant blue. (C) Purified 3xFLAG-KAR proteins (15 ng) were treated with Endo H or PNGase F and subjected to immunoblotting using an anti-FLAG M2 antibody. (D-F) Purified 3xFLAG-ELOVL6 (10 ng) and/or 3xFLAG-KAR proteins of either wild type or S189A mutant (20 ng) were reconstituted into proteoliposomes and subjected to immunoblotting using an anti-FLAG M2 antibody (D) or to an <i>in vitro</i> FA elongation assay (E and F). (E) Proteoliposomes were incubated with 8 µM C16∶0-CoA and 27.3 µM [<sup>14</sup>C]malonyl-CoA (1.5 µCi/ml) for 90 min at 37°C in the presence or absence of 1 mM NADPH. After termination of the reactions, lipids were saponified, acidified, extracted, and separated by normal-phase TLC, followed by detection using a bioimaging analyzer BAS-2500. keto, 3-keto-FA; *keto, a by-product of 3-ketoacyl-CoA; hydroxy, 3-hydroxy-FA; **, <i>trans</i>-2-enoyl-FA produced through non-enzymatic conversion or produced by contaminated 3-hydroxyacyl-CoA dehydratase. (F) Values presented are the sum of the reaction products in (E) and represent the mean ± S.D. from three independent experiments. Statistically significant differences are indicated (**p<0.01; <i>t</i>-test).</p
Robust Stability of 2-D Discrete Systems Described by the Fornasini-Marchesini Second Model Employing Quantization/Overflow Nonlinearities
No full textKar, Haranath/0000-0002-4837-1172New criteria for the global asymptotic stability of the uncertain two-dimensional (2-D) discrete systems described by the Fornasini-Marchesini second local state-space model under various combinations of overflow and quantization nonlinearities are established. Sufficient conditions for the uncertain 2-D discrete systems to be free of overflow oscillations under a generalized overflow arithmetic are presented
Asymptotically CAT(0) Groups
No full textWe develop a general theory for asymptotically CAT(0) groups; these are
groups acting geometrically on a geodesic space, all of whose asymptotic cones are CAT(0)
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