30 resultados para 10121028 TM-40


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Seed of 15 species of Brassicaceae were stored hermetically in a genebank (at -5 degrees C to -10 degrees C with c. 3% moisture content) for 40 years. Samples were withdrawn at intervals for germination tests. Many accessions showed an increase in ability to germinate over this period. due to loss in dormancy. Nevertheless, some dormancy remained after 40 years' storage and was broken by pre-applied gibberellic acid. The poorest seed survival occurred in Hormatophylla spinosa. Even in this accession the ability to germinate declined by only 7% between 1966 and 2006. Comparison of seeds from 1966 stored for 40 years with those collected anew in 2006 from the original sampling sites, where possible, showed few differences, other than a tendency (7 of 9 accessions) for the latter to show greater dormancy. These results for hermetic storage at sub-zero temperatures and low moisture contents confirm that long-term seed storage can provide a successful technology for ex situ plant biodiversity conservation.

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This paper presents the experimental results on the low temperature absorption and dispersion properties for a variety of frequently used infrared filter substrate materials. Index of refraction (n) and transmission spectra are presented for a range of temperatures 300-50 K for the Group IV materials silicon (Si) and germanium (Ge), and Group II-VI materials zinc selenide (ZnSe), zinc sulphide (ZnS) and cadmium telluride (CdTe). (C) 2003 Elsevier B.V. All rights reserved.

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The vacuum-deposited layer properties of materials of possible new use in infrared filters and coatings are described. These are comprehensively drawn from the II/VI, the heavy halide and the V/VI glass compounds, and are commercially available in all cases. Novel applications in coatings and filters are given for many of the materials.

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Multiple linear regression is used to diagnose the signal of the 11-yr solar cycle in zonal-mean zonal wind and temperature in the 40-yr ECMWF Re-Analysis (ERA-40) dataset. The results of previous studies are extended to 2008 using data from ECMWF operational analyses. This analysis confirms that the solar signal found in previous studies is distinct from that of volcanic aerosol forcing resulting from the eruptions of El Chichón and Mount Pinatubo, but it highlights the potential for confusion of the solar signal and lower-stratospheric temperature trends. A correction to an error that is present in previous results of Crooks and Gray, stemming from the use of a single daily analysis field rather than monthly averaged data, is also presented.

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At the end of the 20th century, we can look back on a spectacular development of numerical weather prediction, which has, practically uninterrupted, been going on since the middle of the century. High-resolution predictions for more than a week ahead for any part of the globe are now routinely produced and anyone with an Internet connection can access many of these forecasts for anywhere in the world. Extended predictions for several seasons ahead are also being done — the latest El Niño event in 1997/1998 is an example of such a successful prediction. The great achievement is due to a number of factors including the progress in computational technology and the establishment of global observing systems, combined with a systematic research program with an overall strategy towards building comprehensive prediction systems for climate and weather. In this article, I will discuss the different evolutionary steps in this development and the way new scientific ideas have contributed to efficiently explore the computing power and in using observations from new types of observing systems. Weather prediction is not an exact science due to unavoidable errors in initial data and in the models. To quantify the reliability of a forecast is therefore essential and probably more so the longer the forecasts are. Ensemble prediction is thus a new and important concept in weather and climate prediction, which I believe will become a routine aspect of weather prediction in the future. The limit between weather and climate prediction is becoming more and more diffuse and in the final part of this article I will outline the way I think development may proceed in the future.

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BACKGROUND: Dextran-40 is effective in reducing postoperative Doppler-detectable embolization in patients undergoing carotid endarterectomy (CEA). Dextrans are thought to have antithrombotic and antiplatelet effects. The mode of action is unclear. In rats, dextran blocks uptake of tissue plasminogen activator (tPA) by mannose-binding receptors. Because this would have the effect of enhancing endogenous fibrinolysis, we explored this effect of dextran-40 on fibrinolysis in man. METHODS: Twenty patients undergoing endovascular stenting for abdominal aortic aneurysm were randomized to receive 100 mL of 10% dextran-40 or saline, over 1 hour, during their operation in addition to heparin. Blood samples were taken preoperatively, intraoperatively (immediately after operative procedure), and 24 hours postoperatively. Thrombi were formed in a Chandler loop and used to assess endogenous fibrinolysis over 24 hours, measured as the fall in thrombus weight, and the release of fluorescently labelled fibrinogen from the thrombus. Plasma samples were analyzed for markers of fibrinolysis; plasmin-antiplasmin (PAP), PAI-1, and t-PA, and for functional von Willebrand factor (vWF). Platelet response to thrombin and other agonists was measured by flow cytometry. RESULTS: Thrombi formed ex vivo from the intraoperative blood samples from the dextran-treated patients exhibited significantly greater fibrinolysis vs preoperative samples, seen both as a significantly greater percentage reduction in thrombus weight (from 34.7% to 70.6% reduction) and as an 175% increase in the release of fluorescence (P < .05). Fibrinolysis returned to baseline levels the next day. No change was seen in the saline-treated group. Plasma levels of PAP and PAI-1 increased significantly postoperatively in the dextran-treated group vs the saline group (P < .05). The postoperative level of functional VWF was significantly lower in the dextran-treated group vs controls. A specific reduction occurred in the platelet response to thrombin, but not to other agonists, in the intraoperative samples from the dextran-treated group (11.1% vs 37.1%; P = .022), which was not seen in the controls. CONCLUSIONS: These data are consistent with a rise in plasmin due to dextran blockade of tPA uptake in vivo, leading to enhanced fibrinolysis, cleavage of vWF and of the platelet protease-activated receptor-1 (PAR-1) thrombin receptor. This suggests that dextran exerts a combined therapeutic effect, enhancing endogenous fibrinolysis, whilst also reducing platelet adhesion to vWF and platelet activation by thrombin. The proven antithrombotic efficacy of low-dose dextran in carotid surgery may be applicable to wider therapeutic use.

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The effects of forage conservation method on plasma lipids, mammary lipogenesis, and milk fat were examined in 2 complementary experiments. Treatments comprised fresh grass, hay, or untreated (UTS) or formic acid treated silage (FAS) prepared from the same grass sward. Preparation of conserved forages coincided with the collection of samples from cows fed fresh grass. In the first experiment, 5 multiparous Finnish Ayrshire cows (229 d in milk) were used to compare a diet based on fresh grass followed by hay during 2 consecutive 14-d periods, separated by a 5-d transition during which extensively wilted grass was fed. In the second experiment, 5 multiparous Finnish Ayrshire cows (53 d in milk) were assigned to 1 of 2 blocks and allocated treatments according to a replicated 3 × 3 Latin square design, with 14-d periods to compare hay, UTS, and FAS. Cows received 7 or 9 kg/d of the same concentrate in experiments 1 and 2, respectively. Arterial concentrations of triacylglycerol (TAG) and phospholipid were higher in cows fed fresh grass, UTS, and FAS compared with hay. Nonesterified fatty acid (NEFA) concentrations and the relative abundance of 18:2n-6 and 18:3n-3 in TAG of arterial blood were also higher in cows fed fresh grass than conserved forages. On all diets, TAG was the principle source of fatty acids (FA) for milk fat synthesis, whereas mammary extraction of NEFA was negligible, except during zero-grazing, which was associated with a lower, albeit positive calculated energy balance. Mammary FA uptake was higher and the synthesis of 16:0 lower in cows fed fresh grass than hay. Conservation of grass by drying or ensiling had no influence on mammary extraction of TAG and NEFA, despite an increase in milk fat secretion for silages compared with hay and for FAS than UTS. Relative to hay, milk fat from fresh grass contained lower 12:0, 14:0, and 16:0 and higher S3,R7,R11,15-tetramethyl-16:0, cis-9 18:1, trans-11 18:1, cis-9,trans-11 18:2, 18:2n-6, and 18:3n-3 concentrations. Even though conserved forages altered mammary lipogenesis, differences in milk FA composition were relatively minor, other than a higher enrichment of S3,R7,R11,15-tetramethyl-16:0 in milk from silages compared with hay. In conclusion, differences in milk fat composition on fresh grass relative to conserved forages were associated with a lower energy balance, increased uptake of preformed FA, and decreased synthesis of 16:0 de novo in the mammary glands, in the absence of alterations in stearoyl-coenzyme A desaturase activity.

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The dynamics of a small linear dune on the northern margin of the Namib Sand Sea have been monitored using erosion pins placed at the dune tip since 1969. GPS measurements of these pins enabled estimation of the rates of advance and lateral migration of the dune. The average rate of advance of the dune tip over the period 1969–2012 was 1.99 m yr–1 towards 015°. Rates of advance and lateral movement varied over the period of monitoring, with a decrease in rates of advance by a factor of 50%, but an increase in the rate of lateral movement. Changes in dune behavior appear to be related to changes in wind regime and the vegetation cover of the interdune area, as a result of increased rainfall in recent years. This study demonstrates the dynamic nature of the tip of this dune and its sensitivity to changes in winds and sand supply.

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Zinc (Zn) and cadmium (Cd) hyperaccumulation may have evolved twice in the Brassicaceae, in Arabidopsis halleri and in the Noccaea genus. Tandem gene duplication and deregulated expression of the Zn transporter, HMA4, has previously been linked to Zn/Cd hyperaccumulation in A. halleri. Here, we tested the hypothesis that tandem duplication and deregulation of HMA4 expression also occurs in Noccaea. A Noccaea caerulescens genomic library was generated, containing 36,864 fosmid pCC1FOS (TM) clones with insert sizes similar to 20-40 kbp, and screened with a PCR-generated HMA4 genomic probe. Gene copy number within the genome was estimated through DNA fingerprinting and pooled fosmid pyrosequencing. Gene copy numbers within individual clones was determined by PCR analyses with novel locus specific primers. Entire fosmids were then sequenced individually and reads equivalent to 20-fold coverage were assembled to generate complete whole contigs. Four tandem HMA4 repeats were identified in a contiguous sequence of 101,480 bp based on sequence overlap identities. These were flanked by regions syntenous with up and downstream regions of AtHMA4 in Arabidopsis thaliana. Promoter-reporter beta-glucuronidase (GUS) fusion analysis of a NcHMA4 in A. thaliana revealed deregulated expression in roots and shoots, analogous to AhHMA4 promoters, but distinct from AtHMA4 expression which localised to the root vascular tissue. This remarkable consistency in tandem duplication and deregulated expression of metal transport genes between N. caerulescens and A. halleri, which last shared a common ancestor > 40 mya, provides intriguing evidence that parallel evolutionary pathways may underlie Zn/Cd hyperaccumulation in Brassicaceae.

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Ethnobotanical relevance Cancer patients commonly use traditional medicines (TM) and in Thailand these are popular for both self-medication and as prescribed by TM practitioners, and are rarely monitored. A study was conducted at Wat Khampramong, a Thai Buddhist temple herbal medicine hospice, to document some of these practices as well as the hospice regime. Materials and methods Cancer patients (n=286) were surveyed shortly after admission as to which TMs they had previously taken and perceptions of effects experienced. They were also asked to describe their current symptoms. Treatment at the hospice is built upon an 11-herb anti-cancer formula, yod-ya-mareng, prescribed for all patients, and ideally, its effects would have been evaluated. However other herbal medicines and holistic practices are integral to the regime, so instead we attempted to assess the value of the patients׳ stay at the hospice by measuring any change in symptom burden, as they perceived it. Surviving patients (n=270) were therefore asked to describe their symptoms again just before leaving. Results 42% of patients (120/286; 95% CI 36.4%, 47.8%) had used herbal medicines before their arrival, with 31.7% (38/120; 95% CI 24%, 40.4%) using several at once. Mixed effects were reported for these products. After taking the herbal regime at Khampramong, 77% (208/270 95% CI; 71.7%, 81.7%) reported benefit, and a comparison of the incidence of the most common (pain, dyspepsia, abdominal or visceral pain, insomnia, fatigue) showed statistical significance (χ2 57.1, df 7, p<0.001). Conclusions A wide range of TMs is taken by cancer patients in Thailand and considered to provide more benefit than harm, and this perception extends to the temple regime. Patients reported a significant reduction in symptoms after staying at Khampramong, indicating an improvement in quality of life, the aim of hospices everywhere. Based on this evidence, it is not possible to justify the use of TM for cancer in general, but this study suggests that further research is warranted. The uncontrolled use of TMs, many of which are uncharacterised, raises concerns, and this work also highlights the fact that validated, robust methods of assessing holistic medical regimes are urgently needed.

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A well-known histopathological feature of diseased skin in Buruli ulcer (BU) is coagulative necrosis caused by the Mycobacterium ulcerans macrolide exotoxin mycolactone. Since the underlying mechanism is not known, we have investigated the effect of mycolactone on endothelial cells, focussing on the expression of surface anticoagulant molecules involved in the protein C anticoagulant pathway. Congenital deficiencies in this natural anticoagulant pathway are known to induce thrombotic complications such as purpura fulimans and spontaneous necrosis. Mycolactone profoundly decreased thrombomodulin (TM) expression on the surface of human dermal microvascular endothelial cells (HDMVEC) at doses as low as 2ng/ml and as early as 8hrs after exposure. TM activates protein C by altering thrombin’s substrate specificity, and exposure of HDMVEC to mycolactone for 24 hours resulted in an almost complete loss of the cells’ ability to produce activated protein C. Loss of TM was shown to be due to a previously described mechanism involving mycolactone-dependent blockade of Sec61 translocation that results in proteasome-dependent degradation of newly synthesised ER-transiting proteins. Indeed, depletion from cells determined by live-cell imaging of cells stably expressing a recombinant TM-GFP fusion protein occurred at the known turnover rate. In order to determine the relevance of these findings to BU disease, immunohistochemistry of punch biopsies from 40 BU lesions (31 ulcers, nine plaques) was performed. TM abundance was profoundly reduced in the subcutis of 78% of biopsies. Furthermore, it was confirmed that fibrin deposition is a common feature of BU lesions, particularly in the necrotic areas. These findings indicate that there is decreased ability to control thrombin generation in BU skin. Mycolactone’s effects on normal endothelial cell function, including its ability to activate the protein C anticoagulant pathway are strongly associated with this. Fibrin-driven tissue ischemia could contribute to the development of the tissue necrosis seen in BU lesions.

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At the Paris Peace Conferences of 1918-1919, new states aspiring to be nation-states were created for 60 million people, but at the same time 25 million people found themselves as ethnic minorities. This change of the old order in Europe had a considerable impact on one such group, more than 3 million Bohemian German-speakers, later referred to as Sudeten Germans. After the demise of the Habsburg Empire In 1918, they became part of the new state of Czechoslovakia. In 1938, the Munich Agreement – prelude to the Second World War – integrated them into Hitler’s Reich; in 1945-1946 they were expelled from the reconstituted state of Czechoslovakia. At the centre of this War Child case study are German children from the Northern Bohemian town and district, formerly known as Gablonz an der Neisse, famous for exquisite glass art, now Jablonec nad Nisou in the Czech Republic. After their expulsion they found new homes in the post-war Federal Republic of Germany. In addition, testimonies have been drawn upon of some Czech eyewitnesses from the same area, who provided their perspective from the other side, as it were. It turned out to be an insightful case study of the fate of these communities, previously studied mainly within the context of the national struggle between Germans and Czechs. The inter-disciplinary research methodology adopted here combines history and sociological research to demonstrate the effect of larger political and social developments on human lives, not shying away from addressing sensitive political and historical issues, as far as these are relevant within the context of the study. The expellees started new lives in what became Neugablonz in post-war Bavaria where they successfully re-established the industries they had had to leave behind in 1945-1946. Part 1 of the study sheds light on the complex Czech-German relationship of this important Central European region, addressing issues of democracy, ethnicity, race, nationalism, geopolitics, economics, human geography and ethnography. It also charts the developments leading to the expulsion of the Sudeten Germans from Czechoslovakia after 1945. What is important in this War Child study is how the expellees remember their history while living as children in Sudetenland and later. The testimony data gained indicate that certain stereotypes often repeated within the context of Sudeten issues such as the confrontational nature of inter-ethnic relations are not reflected in the testimonies of the respondents from Gablonz. In Part 2 the War Child Study explores the memories of the former Sudeten war children using sociological research methods. It focuses on how they remember life in their Bohemian homeland and coped with the life-long effects of displacement after their expulsion. The study maps how they turned adversity into success by showing a remarkable degree of resilience and ingenuity in the face of testing circumstances due to the abrupt break in their lives. The thesis examines the reasons for the relatively positive outcome to respondents’ lives and what transferable lessons can be deduced from the results of this study.