175 research outputs found
Improvments in design and manufacture of circuitry insert molded switch components
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1994, and Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, 1994.by Albert A. Eliasen.M.S
Involuntary Thumb Flexion on Neurological Examination: An Unusual Form of Upper Limb Dystonia in the Faroe Islands
Background: The prevalence of dystonia varies worldwide. A prior report suggested a high prevalence of focal dystonia in the Faroese population, possibly reflecting a founder effect. During standardized neurological examination as part of an ongoing neuroepidemiologic study in the Faroe Islands, we noted an unusual phenomenon of thumb flexion during repetitive hand movements in a subset of subjects and sought to define its phenomenology. Methods: We requested commentary from a panel of dystonia experts regarding the phenomenology of the movements. These experts reviewed the videotaped neurological examination. Results: Among the experts, dystonia was the leading diagnosis. Alternate causes were considered, but deemed less likely. Discussion: Diagnosis of dystonia requires careful clinical assessment and consideration of associated features. We report a novel form of dystonia, not previously described to our knowledge, in this isolated population. Further studies of dystonia prevalence in the Faroe Islands are merited to characterize its burden in this population and its specific clinical characteristics
Involuntary Thumb Flexion on Neurological Examination: An Unusual Form of Upper Limb Dystonia in the Faroe Islands
Background: The prevalence of dystonia varies worldwide. A prior report suggested a high prevalence of focal dystonia in the Faroese population, possibly reflecting a founder effect. During standardized neurological examination as part of an ongoing neuroepidemiologic study in the Faroe Islands, we noted an unusual phenomenon of thumb flexion during repetitive hand movements in a subset of subjects and sought to define its phenomenology.
Methods: We requested commentary from a panel of dystonia experts regarding the phenomenology of the movements. These experts reviewed the videotaped neurological examination.
Results: Among the experts, dystonia was the leading diagnosis. Alternate causes were considered, but deemed less likely.
Discussion: Diagnosis of dystonia requires careful clinical assessment and consideration of associated features. We report a novel form of dystonia, not previously described to our knowledge, in this isolated population. Further studies of dystonia prevalence in the Faroe Islands are merited to characterize its burden in this population and its specific clinical characteristics.
Keywords: Dystonia, focal dystonia, Faroe Islands, thumb flexion, phenomenolog
Implementering af mere selektive og skånsomme fiskerier: Konklusioner, anbefalinger og perspektivering
Arene oxidation with malonoyl peroxides
Malonoyl peroxide 7, prepared in a single step from the commercially available diacid, is an effective reagent for the
oxidation of aromatics. Reaction of an arene with peroxide 7 at room temperature leads to the corresponding protected phenol
which can be unmasked by aminolysis. An ionic mechanism consistent with the experimental findings and supported by isotopic
labeling, Hammett analysis, EPR investigations and reactivity profile studies is proposed
Nanoelectromechanical coupling in fullerene peapods probed via resonant electrical transport experiments
Fullerene peapods, that is carbon nanotubes encapsulating fullerene
molecules, can offer enhanced functionality with respect to empty nanotubes.
However, the present incomplete understanding of how a nanotube is affected by
entrapped fullerenes is an obstacle for peapods to reach their full potential
in nanoscale electronic applications. Here, we investigate the effect of C60
fullerenes on electron transport via peapod quantum dots. Compared to empty
nanotubes, we find an abnormal temperature dependence of Coulomb blockade
oscillations, indicating the presence of a nanoelectromechanical coupling
between electronic states of the nanotube and mechanical vibrations of the
fullerenes. This provides a method to detect the C60 presence and to probe the
interplay between electrical and mechanical excitations in peapods, which thus
emerge as a new class of nanoelectromechanical systems.Comment: 7 pages, 3 figures. Published in Nature Communications. Free online
access to the published version until Sept 30th, 2010, see
http://www.nature.com/ncomms/journal/v1/n4/abs/ncomms1034.htm
Charge transport through single molecules, quantum dots, and quantum wires
We review recent progresses in the theoretical description of correlation and
quantum fluctuation phenomena in charge transport through single molecules,
quantum dots, and quantum wires. A variety of physical phenomena is addressed,
relating to co-tunneling, pair-tunneling, adiabatic quantum pumping, charge and
spin fluctuations, and inhomogeneous Luttinger liquids. We review theoretical
many-body methods to treat correlation effects, quantum fluctuations,
nonequilibrium physics, and the time evolution into the stationary state of
complex nanoelectronic systems.Comment: 48 pages, 14 figures, Topical Review for Nanotechnolog
Proizvodne varijable koje utječu na svojstva peleta u peletiranju taljenjem sa smjesom voskova u sferonizatoru za laboratorijsku proizvodnju
The purpose of the study was to evaluate the suitability of laboratory scale spheronizer for the production of spherical pellets loaded with diltiazem hydrochloride by wax combination. The 1:1 combination of cetyl alcohol and hydrogenated castor oil, as low and high melting point waxes, were used. The various production variables affecting the different characteristics of pellets and the process efficiency were evaluated. Drug loaded pellets were evaluated for drug release in distilled water. Bowl temperature primarily affects the sphericity and adhesion of pellets to the bowl. Mass temperature has a pronounced effect on size, size distribution and sphericity of pellets. Wax concentration affects all characteristics of pellets but adhesion was least affected. The effect of these three variables can be compensated by optimizing the friction plate speed. It has been found that the highest yield of pellets (8501400 m) with maximum sphericity can be produced by using 45 C bowl temperature, 52 C mass temperature and 1400 rpm friction plate speed.Cilj rada bio je pripraviti sferične pelete u laboratorijskom sferonizatoru koristeći smjesu voskova. Cetilni alkohol kao vosak niskog tališta i hidrogenirano ricinusovo ulje kao vosak visokog tališta, upotrebljeni su u omjeru 1:1. Proučavan je utjecaj proizvodnih varijabli na svojstva peleta i efikasnost proizvodnje te brzinu oslobađanja ljekovite tvari iz peleta u destiliranoj vodi. Na sferičnost i adhezivnost peleta najviše utječe temperatura peletiranja. Temperatura mase ima i značajan utjecaj na veličinu, raspodjelu veličine peleta i sferičnost. Koncentracija voska utječe na sva svojstva peleta, ali najmanje na adhezivnost. Učinak tih triju varijabli može se kompenzirati optimiziranjem brzine ploče za trenje. Pronađeno je da najveće iskorištenje peleta (8501400 microm) s najboljom sferičnošću ako je temperatura peletiranja 45 oC, temperatura mase 52 oC, a brzina ploče za trenje 1400 rpm
History of climate modeling
The history of climate modeling begins with conceptual models, followed in the 19th century by mathematical models of energy balance and radiative transfer, as well as simple analog models. Since the 1950s, the principal tools of climate science have been computer simulation models of the global general circulation. From the 1990s to the present, a trend toward increasingly comprehensive coupled models of the entire climate system has dominated the field. Climate model evaluation and intercomparison is changing modeling into a more standardized, modular process, presenting the potential for unifying research and operational aspects of climate science. WIREs Clim Change 2011 2 128–139 DOI: 10.1002/wcc.95 For further resources related to this article, please visit the WIREs websitePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79438/1/95_ftp.pd
Report of Working Group on Widely Distributed Stocks (WGWIDE).
As a consequence of the impact of the COVID pandemic on international travel which prevented the traditional meeting from taking place, the Working Group on Widely Distributed Stocks (WGWIDE) met online via WebEx hosted by ICES. Prior to the 2020 meeting, the generic ToRs for species and regional working groups were re-prioritised by ACOM to allow the WG to focus primarily on those ToRs most applicable to the provision of advice. WGWIDE reports on the status and considerations for management of Northeast Atlantic mackerel, blue whiting, Western and North Sea horse mackerel, Northeast Atlantic boarfish, Norwegian springspawning herring, striped red mullet (Subareas 6, 8 and Divisions 7.a-c, e-k and 9.a), and red gurnard (Subareas 3, 4, 5, 6, 7, and 8) stocks. Northeast Atlantic (NEA) Mackerel. This stock is highly migratory and widely distributed throughout the Northeast Atlantic with significant fisheries is most ICES subareas. A diverse range of fleets from smaller artisanal, handline vessels to large (100m+) factory freezer vessels and modern RSW trawlers and purse seiners take part in what is one of the most valuable European fisheries. The assessment conducted in 2020 is an update assessment, based on the configuration agreed during the most recent inter-benchmark exercise in 2019 and incorporates the most recent data available from sampling of the commercial catch in 2019, the final 2019 egg survey SSB estimate, an updated recruitment index and tagging time series along with 2020 survey data from the IESSNS swept area survey. Advice is given based on stock reference points which were updated during a management strategy evaluation carried out in 2020. Following a strong increase from 2007 to 2014, SSB has been declining although it remains well above MSY Btrigger. Fishing mortality has been below FMSY since 2016. There have been a number of large year classes since 2001 with above average recruitment over much of the most recent decade. Blue Whiting. This pelagic gadoid is widely distributed in the eastern part of the North Atlantic. The 2020 update assessment followed the protocol from the most recent inter-benchmark in 2016 and used preliminary catch data from 2020. Due to the cancellation of the 2020 acoustic survey, this data was not available. The effect on the assessment was minimal and limited to increases in uncertainty of the terminal year estimates. The SSB continues to decrease from the most recent maximum in 2017 mainly due to below average recruitment since 2017, although it remains above MSY Btrigger. Fishing mortality has been above FMSY since 2014. Norwegian Spring Spawning Herring. This is one of the largest herring stocks in the world. It is highly migratory, spawning along the Norwegian coast and feeding throughout much of the Norwegian Sea. The 2020 assessment is based on an implementation of the XSAM assessment model introduced at the benchmark in 2016. This years’ assessment indicates that the stock is continuing to decline from the peak in 2008 of 7Mt to just above MSY Btrigger due to successive years of average or below average recruitment. Catch advice for 2021 is given on the basis of the agreed management plan and represents a substantial increase over the 2020 advice due to an upward revision in the estimate of the 2016 year-class which is considered to be the most significant year-class since 2004
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