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Large Quantities (large + quantity)
Selected AbstractsOrganophosphorus pesticides in storm-water runoff from southern California (USA)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2004Kenneth Schiff Abstract Large quantities of the organophosphorus (OP) pesticides diazinon and chlorpyrifos are applied to California (USA) watersheds every year, but few data are available on the sources of OP pesticides in urban watersheds. The goal of this study was to characterize diazinon and chlorpyrifos concentrations from different land uses indicative of source categories in urban southern California watersheds. This characterization included analysis of 128 runoff samples from eight different land uses over five storm events. Diazinon was consistently detected (93% of samples) during this study, whereas chlorpyrifos was not consistently detected (12% of samples). The mixed agricultural land use had the highest flow weighted mean (FWM) concentration of diazinon (4,076 ng/L), which exceeded the next-highest land-use categories (commercial and residential) by one to two orders of magnitude (324,99 ng/L, respectively). Open space had the lowest concentration of diazinon (<20 ng/L). Concentrations of diazinon at replicate land-use sites and during replicate storm events at the same site were highly variable. The difference in diazinon FWM concentrations among replicate sites ranged from 1.5-fold to 45-fold. The difference in diazinon FWM concentrations among storms at the same site ranged from 1.25-fold to 30-fold. Part of this variability is a response to the temporal patterns observed within a storm event. The majority of land-use site-events had peak concentrations before peak flow indicating a first-flush effect, but this was not always a predictable temporal trend. The first-flush effect was rarely evident in terms of mass loadings because flows can range orders of magnitude during a single event in highly impervious urban watersheds. Flow variability thus overwhelms the variability in diazinon concentrations attributable to the first-flush effect. [source] Bioleaching of copper and other metals from low-grade oxidized mining ores by Aspergillus nigerJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2003Catherine N Mulligan Abstract A study was initiated to determine the feasibility of using the fungus Aspergillus niger for bioleaching metals from oxide low-grade ore. Large quantities of the metals are embodied in the low-grade ores and mining residues that can be recovered. Presently available techniques (pyrometallurgical and hydrometallurgical) are expensive or may have a negative impact on the environment. An oxidized mining ore containing mainly copper (7245 mg kg,1 residue) was studied. In this study, the fungus A niger produced a variety of organic acids. Addition of small quantities of sulfuric acid enhanced the organic acids, efficiency. Various agricultural wastes were evaluated as substrates and a maximum solubilization of 68% for copper for a medium containing potato peels was achieved. In conclusion, leaching of copper from a mining ore is technically feasible using A niger. Further research must be performed to increase the rate of copper removal. Copyright © 2003 Society of Chemical Industry [source] Baculovirus expression of erythrovirus V9 capsids and screening by ELISA: Serologic cross-reactivity with erythrovirus B19JOURNAL OF MEDICAL VIROLOGY, Issue 2 2002Erik D. Heegaard Abstract Diagnosis of erythrovirus B19 (B19) relies on serology and the detection of viral DNA. Recently, a distinct erythrovirus isolate termed V9, markedly different from erythrovirus B19 (>,11% nucleotide disparity), was isolated. Standard B19 PCR assays were inconclusive and serologic tests failed to categorize V9 as an acute B19-like infection. Sequencing, combined with PCR studies, have since demonstrated the need for specific and differentiated techniques when examining samples for possible B19 or V9 viremia. The antigenic properties of the V9 capsid proteins have not been characterized previously. To address this question, V9 VP1 and VP2 open reading frames were cloned and expressed in insect cells using a baculovirus vector. Large quantities of purified recombinant V9 capsid protein were produced and electron micrographs revealed self-assembly of V9 VP1/VP2 and VP2 capsids into empty icosahedral erythrovirus-like particles with a diameter of ,23 nm. Screening of a panel of 270 clinical samples for the presence of V9 IgM and IgG antibodies in ELISA showed 100% serologic cross-reactivity between B19 and V9 when comparing V9 VP2 capsids to a commercial B19 VP2 assay. This suggests that both a V9 and a B19 antibody response may be diagnosed equally well by ELISA using either V9 or B19 recombinant capsids as antigen source. Retrospectively, translation of the V9 sequence indicates that despite a significant genetic variation on the DNA level, the majority of the discrepant DNA sequence represents silent mutations leading to an amino acid sequence very similar to the known B19 strains (96,97% homology). J. Med. Virol. 66:246,252, 2002. © 2002 Wiley-Liss, Inc. [source] Colon Delivery Efficiencies of Intestinal Pressure-controlled Colon Delivery Capsules Prepared by a Coating Machine in Human SubjectsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2000ZHAOPENG HU Large quantities of pressure-controlled colon delivery capsules (PCDCs) were prepared by a Hicoater-mini pharmaceutical coating machine and colon delivery efficiencies were evaluated in man. Caffeine powder as a model drug was suspended with a polyethylene glycol (PEG) 1000 suppository base at 50°C, and was hardened in no. 0- and no. 2-sized capsular shapes. The capsule-shaped suppositories were coated with 5% w/v ethanolic ethylcellulose (7G grade) solution using the coating machine. By increasing the coating weight of ethylcellulose from 28.6 ± 1.1 mg to 45.3 ± 0.2 mg, the mean coating thickness of no. 0 PCDCs increased from 56 ± 1 ,m to 64 ± 1 ,m. With no. 2 PCDCs, the mean coating thickness increased from 50 ± 1 ,m to 57 ± 1 ,m by increasing the coating weight of ethylcellulose from 8.1 ± 0.5 mg to 11.2 ± 0.3 mg. The no. 0 PCDCs, having a mean ethylcellulose coating membrane thicknesses of 56± 1 ,m (type 1) and 64 ± 1 ,m (type 2), as well as no. 2 PCDCs, having thicknesses of 50 ± 1 ,m (type 3) and 57 ± 1 ,m (type 4), were used for in-vivo evaluation in man. After oral administration of test preparations containing 75 mg of caffeine, saliva samples were obtained and salivary caffeine levels were measured by an HPLC method. The first appearance time, Ti, of caffeine in the saliva was used as a parameter for the estimation of the release time of caffeine from PCDCs in the gastrointestinal tract. The mean Ti values of no. 0 PCDCs were 3.3 ± 0.3 h for type-1 and 5.3 ± 0.3 h for type-2 preparations while the mean Ti values of no. 2 PCDCs were 4.3 ± 0.5 h for type 3 and 5.3 ± 0.3 h for type 4. There were good correlations between ethylcellulose coating membrane thicknesses and in-vivo Ti values. A colon arrival time of 5 h was reported in our subjects by gastrointestinal magnetomarkergraphy. PCDCs having a mean coating thickness of 64± 1 ,m for no. 0 capsules and of 57 ± 1 ,m for no. 2 capsules were thought to deliver caffeine to the human colon efficiently. [source] Detection of new amino acid markers of liver trauma by proton nuclear magnetic resonance spectroscopyLIVER INTERNATIONAL, Issue 6 2006Priyadarshi Ranjan Abstract: Objective: We examined serum in patients of liver injury to explore the possible clinical application of abnormal micrometabolites as a marker of liver injury and severity in cases of traumatic liver damage. Methods: Serum were screened by proton nuclear magnetic resonance spectroscopy in 96 patients with varying degree of liver injury and compared with concentrations in healthy control volunteers. Results: Large quantities of phenylalanine and tyrosine were detected by spectroscopic analysis in patients with liver injury but not in those without liver injury (P<0.001). Proton nuclear magnetic resonance spectroscopy revealed two unique amino acids, phenylalanine and tyrosine, in the sera of the subjects with liver injury, irrespective of the extent and type of injury gauged by radiology or laparotomy. Phenylalanine spectrum was obtained in all 84 patients with liver injury (100% sensitivity) whereas tyrosine spectrum was present in 83 out of 84 patients (98.8% sensitivity) suggesting that these amino acids were specifically released in the patients of liver injury. Significant correlations were observed between phenylalanine and tyrosine concentrations and total bilirubin levels and albumin levels. Serum phenylalanine and tyrosine concentrations correlated well with imaging and laparotomy findings of liver injury. Conclusion: Phenylanaline and tyrosine appear to be specific and new markers of liver injury. [source] Insecticide resistance in vector mosquitoes in ChinaPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 11 2006Feng Cui Abstract Because of their special behaviour, physiology and close relationship with humans, mosquitoes act as one of the most important vectors of human diseases, such as filariasis, Japanese encephalitis, dengue and malaria. The major vector mosquitoes are members of the Culex, Aedes and Anopheles genera. Insecticides play important roles in agricultural production and public health, especially in a country with a huge human population, like China. Large quantities of four classes of insecticides, organochlorines, organophosphates, carbamates and pyrethroids, are applied annually to fields or indoors in China, directly or indirectly bringing heavy selection pressure on vector populations. The seven major species of vector mosquito in China are the Culex pipiens L. complex, C. tritaeniorhynchus Giles, Anopheles sinensis Wied., A. minimus Theobald, A. anthropophagus Xu & Feng, Aedes albopictus (Skuse) and Ae. aegypti L., and all have evolved resistance to all the above types of insecticide except the carbamates. The degree of resistance varies among mosquito species, insecticide classes and regions. This review summarizes the resistance status of these important vector mosquitoes, according to data reported since the 1990s, in order to improve resistance management and epidemic disease control, and to communicate this information from China to the wider community. Copyright © 2006 Society of Chemical Industry [source] Real-time data-based risk assessment for hazard installations storing flammable gasPROCESS SAFETY PROGRESS, Issue 3 2008Zhou Jianfeng Abstract Large quantities of dangerous substances, especially explosive or flammable gases, are processed or stored in hazard installations. A risk-based warning/early-warning system for major hazard installations is very important for the prevention of major accidents. The real-time data-based risk and the risk factors are analyzed in this article, and a fuzzy logic based real-time risk assessment method is proposed. On the basis of fuzzy logic theory, the likelihood of an accident occurrence and the consequence of the accident can be assessed, and the risk value or risk level can be evaluated by utilizing a risk matrix. The method takes advantage of the real-time data acquired from the safety monitoring system so that the change in the risk can be determined as the accident develops. The risk assessment simulation of a vapor cloud explosion (VCE) accident caused by gas leaked from an liquefied petroleum gas tank is performed. It is shown that the risk of a VCE accident varies with the change of the monitored data. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008 [source] Commercializing bycatch can push a fishery beyond economic extinctionCONSERVATION LETTERS, Issue 4 2010Aaron Savio Lobo Abstract Tropical bottom trawling is among the most destructive fishing practices, catching large quantities of bycatch, which are usually discarded. We used questionnaire surveys of trawl fishers to look at changes in catches over the last 30 years (1978,2008) along India's Coromandel Coast. We show that catches and income from target species have declined sharply over the last two decades. Meanwhile, costs of fishing have increased substantially and now almost exceed income from target species. Over the same period, bycatch (which was traditionally discarded) has now become increasingly marketable, being sold for local consumption, and as fish meal to supply the region's rapidly growing poultry industry. Without this income from bycatch, the fishery would scarcely be economically viable. While such a change in the use of bycatch is good news in terms of reducing waste and improving livelihoods, it is also responsible for pushing the Indian bottom trawl fishery beyond the economic extinction of its target species. [source] Excessive belching and aerophagia: two different disordersDISEASES OF THE ESOPHAGUS, Issue 4 2010Albert J. Bredenoord SUMMARY Belching is physiological venting of excessive gastric air. Excessive and bothersome belching is a common symptom, which is often seen in patients with functional dyspepsia and gastroesophageal reflux disease. Other symptoms are usually predominant. However, a small group of patients complain of isolated excessive belching, with a frequency of several belches per minute. In these patients, the eructated air does not originate from the stomach but is sucked or injected in the esophagus from the pharynx and expelled immediately afterward in oral direction. This behavior is called supragastric belching because the air does not originate from the stomach and does not reach the stomach either. Excessive belching can be treated by speech therapy or behavior therapy. The term aerophagia should be reserved for those patients where there is evidence that they swallow air too frequently and in too large quantities. These patients have excessive amounts of intestinal gas visualized on a plain abdominal radiogram and their primary symptoms are bloating and abdominal distension and they belch only to a lesser degree. Aerophagia and excessive supragastric belching are thus two distinct disorders. [source] Scale-dependent controls upon the fluvial export of large wood from river catchmentsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2009Jung Il Seo Abstract The annual fluvial export of large wood (LW) was monitored by local reservoir management offices in Japan. LW export per unit watershed area was relatively high in small watersheds, peaked in intermediate watersheds, and decreased in large watersheds. To explain these variations, we surveyed the amount of LW with respect to channel morphology in 78 segments (26 segments in each size class) in the Nukabira River, northern Japan. We examined the differences in LW dynamics, including its recruitment, transport, storage, and fragmentation and decay along the spectrum of watershed sizes. We found that a large proportion of LW produced by forest dynamics and hillslope processes was retained because of the narrower valley floors and lower stream power in small watersheds. The retained LW pieces may eventually be exported during debris flows. In intermediate watersheds, the volume of LW derived from hillslopes decreased substantially with reductions in the proportion of channel length bordered by hillslope margins, which potentially deliver large quantities of LW. Because these channels have lower wood piece length to channel width ratios and higher stream power, LW pieces can be transported downstream. During transport, LW pieces are further fragmented and can be more easily transported. Therefore, the fluvial export of LW is maximized in intermediate watersheds. Rivers in large watersheds, where the recruitment of LW is limited by the decreasing hillslope margins, cannot transport LW pieces because of their low stream power, and thus LW pieces accumulate at various storage sites. Although these stored LW pieces can be refloated and transported by subsequent flood events, they may also become trapped by obstacles such as logjams and standing trees on floodplains and in secondary channels, remaining there for decades and eventually decaying into fine organic particles. Thus, the fluvial export of LW pieces is low in large watersheds. Copyright © 2009 John Wiley & Sons, Ltd. [source] Wood storage in a wide mountain river: case study of the Czarny Dunajec, Polish CarpathiansEARTH SURFACE PROCESSES AND LANDFORMS, Issue 12 2005omiej Wy Abstract Storage of large woody debris in the wide, mountain, Czarny Dunajec River, southern Poland, was investigated following two floods of June and July 2001 with a seven-year frequency. Within a reach, to which wood was delivered only by bank erosion and transport from upstream, wood quantities were estimated for eighty-nine, 100 m long, channel segments grouped into nine sections of similar morphology. Results from regression analysis indicated the quantity of stored wood to be directly related to the length of eroded, wooded banks and river width, and inversely related to unit stream power at the flood peak. The largest quantities of wood (up to 33 t ha,1) were stored in wide, multi-thread river sections. Here, the relatively low transporting ability of the river facilitated deposition of transported wood while a considerable length of eroded channel and island banks resulted in a large number of trees delivered from the local riparian forest. In these sections, a few morphological and ecological situations led to the accumulation of especially large quantities of wood within a small river area. Very low amounts of wood were stored in narrow, single-thread sections of regulated or bedrock channel. High stream power facilitated transport of wood through these sections while the high strength of the banks and low channel sinuosity prevented bank retreat and delivery of trees to the channel. Considerable differences in the character of deposited wood existed between wide, multi-thread channel sections located at different distances below a narrow, 7 km long, channellized reach of the river. Wood deposited close to the downstream end of the channellized reach was highly disintegrated and structured into jams, whereas further downstream well preserved shrubs and trees prevailed. This apparently reflects differences in the distance of wood transport and shows that in a mountain river wider than the height of trees growing on its banks, wood can be transported long distances along relatively narrow, single-thread reaches but is preferentially deposited in wide, multi-thread reaches. Copyright © 2005 John Wiley & Sons, Ltd. [source] The epidemiology of cannabis use and cannabis-related harm in Australia 1993,2007ADDICTION, Issue 6 2010Amanda Roxburgh ABSTRACT Aims To examine trends in patterns of cannabis use and related harm in the Australian population between 1993 and 2007. Design Analysis of prospectively collected data from: (1) the National Drug Strategy Household Survey (NDSHS) and Australian Secondary Student Alcohol and Drug Survey (ASSADS); (2) the National Hospital Morbidity Database (NHMD); and (3) the Alcohol and Other Drug Treatment Services National Minimum Dataset (AODTS-NMDS). Participants Australians aged 14 years and over from the general population; students aged 12,17 years; public and private hospital in-patients; public and private in-patients and out-patients attending for drug treatment. Measurement Prevalence of 12-month cannabis use among the general population and secondary students. Proportions in the general population by age group reporting: daily cannabis use; difficulties in controlling cannabis use; and heavy cannabis use on each occasion. Number of hospital and treatment presentations for cannabis-related problems. Findings Prevalence of past-year cannabis use has declined in the Australian population since the late 1990s. Among those reporting past-year use, daily use is prevalent among 40,49-year-olds, while heavy patterns of use are prevalent among 14,19-year-olds. Hospital presentations for cannabis-related problems reflect similar trends. Past-year cannabis use has decreased among the 10,19-year age group, but those who are daily users in this age group report using large quantities of cannabis. Conclusions Despite declines in the prevalence of cannabis use, continued public health campaigns warning of the harms associated with cannabis use are essential, aimed particularly at users who are already experiencing problems. The increasing demand for treatment for cannabis problems in Australia suggests the need for more accessible and more effective interventions for cannabis use disorders. [source] Comparative measures of the toxicity of component chemicals in aircraft deicing fluidENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2000Jeffrey S. Cornell Abstract Acraft deicingoperationsarea necessarypart of safe air travel, but release large quantities of aircraft deicing fluids (ADFs) to the environment. Effective measures to mitigate the environmental impacts of deicing operations are hindered because of the negative effects some ADF chemicals have on treatment systems and because of the poorly characterized toxicity of ADF components. This research investigated the contributions of environmentally significant concentrations of selected ADF components to the toxicity of ADF-containing waste streams, and to the inhibition of biodegradation of propylene glycol (PG), the most important component of ADF. The component chemicals studied were PG, the corrosion inhibitor 4(5)-methylbenzotriazole (MeBT; common name: tolyltriazole), and proprietary mixes of corrosion inhibitors, buffers, and surfactants referred to as the additive package or AdPack. Relative to PG alone, the different additives increased the toxicity of ADF and decreased PG biodegradation rates. In enrichments of soil microorganisms acclimated to ADF, the MeBT component significantly decreased cell growth rates and yields, and inhibited PG biodegradation to a greater extent than the AdPack. Microtox® tests indicated that MeBT is the ADF component most toxic to microorganisms. However, acute aquatic toxicity tests indicated that the AdPack components were more toxic than MeBT to Ceriodaphnia dubia and Pimephales promelas, although both components were more toxic than PG alone. [source] When do the Costs of Spermatogenesis Constrain Sperm Expenditure?ETHOLOGY, Issue 1 2009Remarks on the Pattern of the Spermatogenic Cycle The costs of spermatogenesis constrain sperm expenditure when sperm production per day is limited. Thus, males are challenged to allocate available resources to sperm production and other life history functions. However, this prevailing assumption is not applicable to species in which spermatogenesis becomes quiescent during the breeding season. Males of these species prepare large quantities of sperm before the breeding season. Among these species, constraints on ejaculates have been intensively investigated in salamanders that deposit spermatophores. Although it is predicted that sperm expenditure should not be limited because of abundantly prepared sperm, spermatophore deposition is often limited during the breeding season when vas deferens are full of sperm. We tested a hypothesis regarding limited spermatophore deposition by measuring sperm quantity and volume of spermatophores sequentially deposited by male eastern newts Notophthalmus viridescens. A male newt rarely deposits more than three spermatophores per mating. If depletion of non-sperm components of spermatophores limits spermatophore deposition, we predicted that spermatophore volume decreases while sperm quantity remains constant as a male deposits more spermatophores. Alternatively, some regulative mechanisms allow a limited portion of available sperm to be expended per mating, in which sperm quantity is predicted to decrease while the spermatophore volume remains constant. Finally, depletion of non-sperm components may regulate sperm expenditure, which predicted that both spermatophore volume and sperm quantity decrease. We found that both sperm quantity and the spermatophore volume decreased as a male deposited more spermatophores during a single mating. Sperm expenditure was constrained without the costs involved in active spermatogenesis, and depletion of non-sperm components likely regulate sperm quantity loaded in spermatophores. In dissociated spermatogenesis, constrained sperm expenditure do not mean that costly spermatogenesis is directly limiting male mating capacity but rather suggest that the evolution of physiological mechanisms regulating sperm expenditure per mating maximizes male reproductive success. [source] Can Russia be Competitive in Agriculture?EUROCHOICES, Issue 3 2003William M. Liefert Summary Can Russia be competitive inAgriculture? Russian agriculture currently is not internationally cost competitive. Since the mid-1990s Russia has imported large volumes of meat, while the grain trade has fluctuated in most years between small net imports and exports. Russia has, however, exported large quantities of key agricultural inputs, including 80 per cent of fertilizer output, mainly to EU countries. Research indicates that Russia has a comparative advantage in producing grain compared to meat, but also a comparative advantage in producing agricultural inputs compared to agricultural outputs. The expected real appreciation of the Russian rouble vis-à-vis Western currencies should further damage Russia's cost competitiveness in meat and grain, but this should be offset by modest productivity growth. An expected rise in consumer income, deriving from relatively high annual GDP growth of about 4,5 per cent, should also stimulate demand for meat imports. In spring 2003, Russia imposed tariff rate quotas on its imports of beef and pork, and a pure quota on imports of poultry. For other agricultural commodities, Russia is pushing in its WTO accession negotiations for allowable agricultural import tariffs that are higher than current levels. Taking these changes together, it is likely that Russia will continue as a big meat importer for about the next ten years,with tariff rate quotas probably determining the level of meat imports,and will become a moderate grain exporter. L'agriculture russepourrait-elle être compétitive ? Actuellement, l'agriculture russe n'est pas compétitive. La Russie a importé de gros volumes de viande depuis le milieu des années 90, tandis que la balance des échanges de céréales oscillait entre les faibles excédents et les faibles déficits. Cependant, la Russie est grande exportatrice d'agro-fournitures dont, en particulier, 80% de sa production d'engrais, principalement vers l'Europe. On montre ici que l'avantage comparatif de la Russie se situe dans les céréales plutôt que dans la viande et, surtout, dans les agro-fournitures plutôt que dans les denrées agricoles. La remontée, à laquelle il faut s'attendre, du rouble vis à vis des devises occidentales, devrait encore diminuer la compétitivité de la Russie en matière de viandes et de céréales, ce qui devrait être compensé par des gains de productivité même faibles. La hausse attendue des revenus des consommateurs, engenderée par une croissance élevée du revenu national, de l'ordre de 4 à 5% par an, devrait aussi stimuler la demande de viande importée. Au printemps 2003, la Russie s'est dotée d'un système de droits sur ses importations hors quotas de viande de bæuf et de pore, ainsi que d'un quota d'importation pour les produits avicoles. En ce qui conceme les autres produits agricoles, dans le cadre des négociations relatives à son entrée dans l'OMC, la Russie s'efforce d'obtenir l'autorisation d'augmenter les taxes à l'importation par rapport à leur niveau actuel. Au total done, à un horizon de l'ordre de dix ans, il est probable que la Russie reste un gros importateur de viandes - le niveau des taxes sur le hors quotas déterminant les niveaux d'importation -, et un modeste exportateur de céréales. Kann Russland auf dem Agrarsektorwettbewerbsfähig sein? Die russische Landwirtschaft ist hinsichtlich der Kosten momentan nicht international wettbewerbsfähig. Seit Mitte der 1990er importiert Russland große Mengen an Fleisch, während der Getreidehandel in den meisten Jahren zwischen geringen Nettoimporten und -exporten schwankte. Russland hat jedoch große Mengen an wichtigen landwirtschaftlichen Vorieistungen, unter anderem 80% seiner Düngerproduktion, hauptsächlich in EU-Länder exportiert. Forschungsergebnisse weisen darauf hin, dass Russland in der Produktion von Getreide verglichen mit Fleisch einen komparativen Vorteil besitzt; dies trifft jedoch ebenfalls auf die Produktion von landwirtschaftlichen Vorieistungen verglichen mit landwirtschaftlichen Endprodukten zu. Es ist anzunehmen, dass die erwartete reale Aufwertung des russischen Rubel gegenüber den westlichen Währungen eine zusätzliche Verschlechterung der russischen Wettbewerbsfähigkeit hinsichtlich der Kosten im Bereich Fleisch und Getreide nach sich zieht; dies sollte sich jedoch durch ein moderates Produktivitätswachstum ausgleichen. Der erwartete Anstieg der Verbrauchereinkommen, der sich aus dem relativ hohen jährlichen Bruttoin-landsproduktzuwachs von ca. 4,5 Prozent ableitet, sollte sich ebenfalls stimulierend auf die Nachfrage nach Fleischimporten auswirken. Im Frühjahr 2003 führte Russland Zolltarifkontingente für seine Schweine- und Rindfleischimporte ein und belegte seine Geflügelfleischimporte mit einem Importkontingent. Im Hinblick auf weitere Agrarerzeugnisse drängt Russland in den WTO-Beitrittsverhandlungen darauf, höhere Einfuhrzölle als die gegenwärtig geltenden zuzulassen. In Anbetracht all dieser Veränderungen ist es wahrscheinlich, dass Russland auch für die kommenden zehn Jahre große Mengen an Fleisch importieren,wobei möglicherweise Zolltarifkontingente die Menge bestimmen werden,und sich zu einem mäßigen Getreideexporteur entwickeln wird. [source] The chemokine receptor CCX-CKR mediates effective scavenging of CCL19 in vitroEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 7 2006Iain Comerford Abstract The chemokines CCL19, CCL21 and CCL25, by signalling through the receptors CCR7 or CCR9, play critical roles in leukocyte homing. They also bind another heptahelical surface protein, CCX-CKR. CCX-CKR cannot couple to typical chemokine receptor signalling pathways or mediate chemotaxis, and its function remains unclear. We have proposed that it controls chemokine bioavailability. Here, using transfected HEK293 cells, we have shown that both CCX-CKR and CCR7 mediate rapid CCL19 internalisation upon initial chemokine exposure. However, internalised CCL19 was more efficiently retained and degraded after uptake via CCX-CKR. More importantly, CCR7 rapidly became refractory for CCL19 uptake, but the sequestration activity of CCX-CKR was enhanced. These properties endowed CCX-CKR with an impressive ability to mediate progressive sequestration and degradation of large quantities of CCL19, and conversely, prevented CCR7-expressing cells from extensively altering their chemokine environment. These differences may be linked to the routes of endocytosis used by these receptors. CCX-CKR, unlike CCR7, was not critically dependent on ,-arrestins or clathrin-coated pits. However, over-expression of caveolin-1, which stabilises caveolae, blocked CCL19 uptake by CCX-CKR while having no impact on other chemokine receptors, including CCR7. These data predict that CCX-CKR scavenges extracellular chemokines in vivo to modify responses through CCR7. See accompanying commentary: http://dx.doi.org/10.1002/eji.200636327 [source] Impact of stone content on water movement in water-repellent sandEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2009E. Urbanek Summary Soils are commonly stony, especially in steep upland or heavily degraded sites. The hydrological effect of large stone contents has been previously investigated in wettable but not in water-repellent soils. For the latter, the focus has instead been on the impact of other soil characteristics (e.g. cracks and macropores) likely to promote water percolation. This paper investigates stone effects on water flow in water-repellent sand under laboratory conditions. Seventy-five experiments were performed on a water-repellent sand mixed with a range of quantities of different-sized wettable and water-repellent stones. The time taken for water to pass through each sand,stone mix, the percolated water volumes and numbers of dry and wet stones following each 60-minute experiment were recorded. At large stone contents (> 55% or > 65% by weight, depending on stone wettability), percolation occurred relatively quickly and in comparatively large quantities. At intermediate stone contents (45,65%) percolation response was variable and at stone contents < 45% for wettable and < 55% for water-repellent soils no water percolation occurred. We argue that with large stone contents flow pathways develop along sand,stone interfaces and a continuous preferential flow path can form provided there are sufficient stone-to-stone connections. The distribution and alignment of the stones, especially at intermediate stone contents, are important for promoting water movement. Water repellency determinations based only on the fine sediment component in stony soils could therefore be misleading as regards determining their hydrological response: the influence of the clastic component must also be considered. [source] The extinct sloth lemurs of MadagascarEVOLUTIONARY ANTHROPOLOGY, Issue 6 2003Laurie R. Godfrey Paleontological expeditions to Madagascar over the past two decades have yielded large quantities of bones of extinct lemurs. These include abundant postcranial and cranial remains of new species belonging to a group of giant extinct lemurs that we have called sloth lemurs due to their remarkable postcranial convergence with arboreal sloths. New fossils have come from a variety of locations in Madagascar, including caves in the Northwest (Anjohibe) and the Ankarana Massif, located in the extreme north, as well as pits in the karstic plains near Toliara in southwestern Madagascar. The most spectacular of these is the extremely deep pit (>100 m) called Ankilitelo, the "place of the three kily trees." These new materials provide insights into the adaptive diversity and evolution of sloth lemurs. New carpal and pedal bones, as well as vertebrae and other portions of the axial skeletons, allow better reconstruction of the positional behavior of these animals. New analytical tools have begun to unlock the secrets of life-history adaptations of the Palaeopropithecidae, making explicit exactly what they had in common with their relatives, the Indriidae. Paleoecological research has elucidated the contexts in which they lived and the likely causes of their disappearance. [source] Evolutionary divergence of valosin-containing protein/cell division cycle protein 48 binding interactions among endoplasmic reticulum-associated degradation proteinsFEBS JOURNAL, Issue 5 2009Giacomo Morreale Endoplasmic reticulum (ER)-associated degradation (ERAD) is a cell-autonomous process that eliminates large quantities of misfolded, newly synthesized protein, and is thus essential for the survival of any basic eukaryotic cell. Accordingly, the proteins involved and their interaction partners are well conserved from yeast to mammals, and Saccharomyces cerevisiae is widely used as a model system with which to investigate this fundamental cellular process. For example, valosin-containing protein (VCP) and its yeast homologue cell division cycle protein 48 (Cdc48p), which help to direct polyubiquitinated proteins for proteasome-mediated degradation, interact with an equivalent group of ubiquitin ligases in mouse and in S. cerevisiae. A conserved structural motif for cofactor binding would therefore be expected. We report a VCP-binding motif (VBM) shared by mammalian ubiquitin ligase E4b (Ube4b),ubiquitin fusion degradation protein 2a (Ufd2a), hydroxymethylglutaryl reductase degradation protein 1 (Hrd1),synoviolin and ataxin 3, and a related sequence in Mr 78 000 glycoprotein,Amfr with slightly different binding properties, and show that Ube4b and Hrd1 compete for binding to the N-terminal domain of VCP. Each of these proteins is involved in ERAD, but none has an S. cerevisiae homologue containing the VBM. Some other invertebrate model organisms also lack the VBM in one or more of these proteins, in contrast to vertebrates, where the VBM is widely conserved. Thus, consistent with their importance in ERAD, evolution has developed at least two ways to bring these proteins together with VCP,Cdc48p. However, the differing molecular architecture of VCP,Cdc48p complexes indicates a key point of divergence in the molecular details of ERAD mechanisms. [source] Regulated expression and intracellular localization of cystatin F in human U937 cellsFEBS JOURNAL, Issue 22 2002Carl-Michael Nathanson Cystatin F is a cysteine peptidase inhibitor recently discovered in haematopoietic cells by cDNA cloning. To further investigate the expression, distribution and properties of the native human inhibitor the promyeloid cell line U937 has been studied. The cells expressed relatively large quantities of cystatin F, which was found both secreted and intracellularly. The intracellular levels were unusually high for a secreted cystatin (, 25% of the cystatin F in 2- or 4-day culture medium). By contrast, U937 cells contained only 3,4% of the related inhibitor, cystatin C. Cystatin F purified from lysates of U937 cells showed three major forms carrying two, one or no carbohydrate chains. Immunocytochemistry demonstrated a marked cytoplasmic cystatin F staining in a granular pattern. Double staining with a marker for endoplasmic reticulum revealed no colocalization for cystatin F. Analysis of the promoter region of the cystatin F gene (CST7) showed that it, like that of the cystatin C gene (CST3), is devoid of typical TATA- and CAAT-box elements. In contrast to the cystatin C promoter, it does not contain multiple Sp1 binding sites, but has a unique site for C/EBP,, possibly explaining the restricted expression of the cystatin F gene. Cells stimulated with all- trans retinoic acid to differentiate them towards a granulocytic pathway, showed a strong (, 18-fold) down-regulation of intracellular cystatin F and almost abolished secreted levels of the inhibitor. Stimulation with tetradecanoyl phorbol acetate, causing monocytic differentiation, also resulted in down-regulation (two fold to threefold) of cystatin F expression, whereas the cystatin C expression was essentially unaltered in both experiments. The results suggest that cystatin F as an intracellular cysteine peptidase inhibitor with readily regulated expression, may be a candidate to control the cysteine peptidase activity known to be essential for antigen presentation in different blood cell lineages. [source] Indole as an intercellular signal in microbial communitiesFEMS MICROBIOLOGY REVIEWS, Issue 4 2010Jin-Hyung Lee Abstract Bacteria can utilize signal molecules to coordinate their behavior to survive in dynamic multispecies communities. Indole is widespread in the natural environment, as a variety of both Gram-positive and Gram-negative bacteria (to date, 85 species) produce large quantities of indole. Although it has been known for over 100 years that many bacteria produce indole, the real biological roles of this molecule are only now beginning to be unveiled. As an intercellular signal molecule, indole controls diverse aspects of bacterial physiology, such as spore formation, plasmid stability, drug resistance, biofilm formation, and virulence in indole-producing bacteria. In contrast, many non-indole-producing bacteria, plants and animals produce diverse oxygenases which may interfere with indole signaling. It appears indole plays an important role in bacterial physiology, ecological balance, and possibly human health. Here we discuss our current knowledge and perspectives on indole signaling. [source] Seabird distribution, abundance and diets in the eastern and central Aleutian IslandsFISHERIES OCEANOGRAPHY, Issue 2005J. JAHNCKE Abstract We examined the hypothesis that seabird distribution, abundance and diets differ among the eastern and central Aleutian Islands in response to distinct marine environments and energy pathways in each region. Research cruises were conducted in June 2001 and May,June 2002. We determined the distribution, abundance, diet and prey consumption of seabirds, and related these to zooplankton abundance and water masses that possess different physical properties. We found that distribution, abundance and diets of seabirds could be partitioned into two regions that correspond to marine environments determined by the extent of the Alaska Coastal Current along the eastern and central Aleutian Islands. Short-tailed shearwaters (Puffinus tenuirostris) were the most abundant seabird in the coastal waters of the eastern Aleutian Islands, and northern fulmars (Fulmarus glacialis) were the most abundant seabird in the oceanic waters of the central Aleutian Islands. Seabird communities in the central and eastern Aleutian Islands were likely associated with different food webs. In the central Aleutian Islands, short-tailed shearwaters and northern fulmars consumed shelf-break species of euphausiids (Thyssanoesa longipes) and oceanic copepods (Neocalanus cristatus), respectively; in the eastern Aleutian Islands, both short-tailed shearwaters and northern fulmars consumed shelf species of euphausiids (T. inermis). Carbon transport to seabirds was highest in Unimak and Akutan Passes where shearwaters removed large quantities of shelf euphausiids, followed by Samalga and Seguam Passes where northern fulmars removed large amounts of oceanic copepods. [source] Micromorphology and plant macrofossil analysis of cattle dung from the Neolithic lake shore settlement of Arbon Bleiche 3GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 6 2001Örni Akeret At the excavation of the Neolithic site of Arbon Bleiche 3, Switzerland (3384,3370 B.C., dated using dendrochronology), objects were found that strongly resembled cow pats. Both micromorphological characteristics and plant macrofossil content confirmed this. Although a detailed micromorphological description was possible, macrofossil analysis turned out to be more difficult than expected because of contamination along fissures. The contents of two of the four coprolites analyzed had conspicuously high amounts of leaves and wood of silver fir (Abies alba). This animal feed may have come in large quantities as a byproduct of house construction. In addition, mistletoe (Viscum album), blackberry (Rubus fruticosus s.l.), and ferns could be identified as animal fodder. © 2001 John Wiley & Sons, Inc. [source] Place Annihilation and Urban Reconstruction: The Experience of Four Towns in Brittany, 1940 to 1960GEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3 2000Hugh Clout Devastation, revival and reconstruction form guiding themes in this discussion of annihilated settlements in north-west France. For reasons of deep-water access and strategic location, the German occupiers decided to construct massive submarine bases at Brest, Lorient and Saint-Nazaire. Allied bombardment devastated the towns that surrounded them during the Second World War, while the heavily defended walled port of Saint-Malo was annihilated in 1944. With peace restored, prisoners of war and local labourers cleared mines, removed debris and installed large quantities of temporary housing. Development plans, drawn up in the interwar years, provided an important starting point for subsequent master plans which shaped postwar reconstruction. Working under the guidance of the Ministry of Reconstruction and Urbanism, chief planners, architects and reconstruction cooperatives refashioned property units and engineered the rebuilding of Brest, Lorient and Saint-Nazaire along thoroughly modern lines; by contrast, Saint-Malo was rebuilt much as it had been before the war. Many of the buildings of the 1950s now require refurbishment, and urgent initiatives need to be taken to revitalise the local economies of these reconstructed towns, whose role as naval bases, military arsenals and shipbuilding centres has contracted in the wake of political détente and deindustrialisation. [source] From agriculture based on fossil fuel resources to agriculture based on biological interactions and matter cycling in agroecosystemsGRASSLAND SCIENCE, Issue 1 2005Masae Shiyomi Abstract The modern system of agriculture, which depends on the consumption of large quantities of fossil fuel, will be forced to change to a system in which matter cycling and the various interactions operating among organisms and between organisms and their environment are effectively used. Three key factors will necessitate this change: the depletion of readily available fossil fuel resources; the leveling-off of the growth and yield response of crops in response to the increase in the use of fertilizers, agrochemicals and big machinery; and the degradation of the environment associated with the consumption of fossil fuels and derived agrochemicals. Therefore, it is essential to further promote the following two types of study: (i) the elucidation of the structure and use of complex biological interactions, and the cause-and-effect relationships among and between organisms in relation to their environment; and (ii) the effective use of matter cycling in agricultural ecosystems. Efficient use of biological interactions and matter cycling will reduce the dependence of agriculture on fossil fuel. [source] One-Step Ionic-Liquid-Assisted Electrochemical Synthesis of Ionic-Liquid-Functionalized Graphene Sheets Directly from Graphite,ADVANCED FUNCTIONAL MATERIALS, Issue 10 2008Na Liu Abstract Graphite, inexpensive and available in large quantities, unfortunately does not readily exfoliate to yield individual graphene sheets. Here a mild, one-step electrochemical approach for the preparation of ionic-liquid-functionalized graphite sheets with the assistance of an ionic liquid and water is presented. These ionic-liquid-treated graphite sheets can be exfoliated into functionalized graphene nanosheets that can not only be individuated and homogeneously distributed into polar aprotic solvents, but also need not be further deoxidized. Different types of ionic liquids and different ratios of the ionic liquid to water can influence the properties of the graphene nanosheets. Graphene nanosheet/polystyrene composites synthesized by a liquid-phase blend route exhibit a percolation threshold of 0.1 vol % for room temperature electrical conductivity, and, at only 4.19 vol %, this composite has a conductivity of 13.84,S m,1, which is 3,15 times that of polystyrene composites filled with single-walled carbon nanotubes. [source] Drinking a lot is good for dendritic cellsIMMUNOLOGY, Issue 4 2006Christopher C. Norbury Summary Macropinocytosis is the actin-dependent formation of large vesicles, which allow the internalization of large quantities of fluid-phase solute. In the majority of cells examined, an exogenous stimulus is required to induce the initiation of this endocytic pathway. However, dendritic cells are thought to constitutively macropinocytose large quantities of exogenous solute as part of their sentinel function. In this review we discuss the evidence that dendritic cells macropinocytose exogenous solute and subsequently present antigenic peptides derived from internalized material to T cells. In addition, we put these data into the context of immune surveillance in vivo. [source] Janus Supraparticles by Induced Phase Separation of Nanoparticles in DropletsADVANCED MATERIALS, Issue 19 2009Rhutesh K. Shah Biphasic Janus particles with a precisely tunable internal morphology are fabricated using a novel, versatile, and robust technique. This technique can be used in conjunction with microfluidics to produce monodisperse particles, or can be combined with bulk emulsification techniques to produce large quantities of particles. [source] The role of the oceans in climateINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 10 2003G. R. Bigg Abstract The ocean is increasingly seen as a vital component of the climate system. It exchanges with the atmosphere large quantities of heat, water, gases, particles and momentum. It is an important part of the global redistribution of heat from tropics to polar regions keeping our planet habitable, particularly equatorward of about 30°. In this article we review recent work examining the role of the oceans in climate, focusing on research in the Third Assessment Report of the IPCC and later. We discuss the general nature of oceanic climate variability and the large role played by stochastic variability in the interaction of the atmosphere and ocean. We consider the growing evidence for biogeochemical interaction of climatic significance between ocean and atmosphere. Air,sea exchange of several radiatively important gases, in particular CO2, is a major mechanism for altering their atmospheric concentrations. Some more reactive gases, such as dimethyl sulphide, can alter cloud formation and hence albedo. Particulates containing iron and originating over land can alter ocean primary productivity and hence feedbacks to other biogeochemical exchanges. We show that not only the tropical Pacific Ocean basin can exhibit coupled ocean,atmosphere interaction, but also the tropical Atlantic and Indian Oceans. Longer lived interactions in the North Pacific and Southern Ocean (the circumpolar wave) are also reviewed. The role of the thermohaline circulation in long-term and abrupt climatic change is examined, with the freshwater budget of the ocean being a key factor for the degree, and longevity, of change. The potential for the Mediterranean outflow to contribute to abrupt change is raised. We end by examining the probability of thermohaline changes in a future of global warming. Copyright © 2003 Royal Meteorological Society [source] Metallodielectric Photonic Crystals Assembled from Monodisperse Spherical Colloids of Bismuth and Lead,ADVANCED MATERIALS, Issue 4 2006Y. Wang Monodisperse metallic and metallodielectric spherical colloids have been synthesized in large quantities and explored as building blocks for fabricating three-dimensional metallodielectric photonic crystals. Both measurements and calculations revealed large photonic bandgaps covering optical wavelengths from the visible up to the near-IR region for the metallic (Bi and Pb) and metallodielectric (with a silica coating) colloids (see Figure). [source] | ||||||||||||||||||||||||||||||||||||||||||||||