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111.
Long unfolded linkers facilitate membrane protein import through the nuclear pore complex 总被引:1,自引:0,他引:1
Meinema AC Laba JK Hapsari RA Otten R Mulder FA Kralt A van den Bogaart G Lusk CP Poolman B Veenhoff LM 《Science (New York, N.Y.)》2011,333(6038):90-93
Active nuclear import of soluble cargo involves transport factors that shuttle cargo through the nuclear pore complex (NPC) by binding to phenylalanine-glycine (FG) domains. How nuclear membrane proteins cross through the NPC to reach the inner membrane is presently unclear. We found that at least a 120-residue-long intrinsically disordered linker was required for the import of membrane proteins carrying a nuclear localization signal for the transport factor karyopherin-α. We propose an import mechanism for membrane proteins in which an unfolded linker slices through the NPC scaffold to enable binding between the transport factor and the FG domains in the center of the NPC. 相似文献
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Straw-rich manure from organic pig farming systems can be composted in passively aerated systems as the high application of straw results in a compost bed with good structure and porosity. The passively aerated composting process was simulated in one-dimensional reactors of 2 m3 for straw-rich manure with compost bed densities of 1100, 700 and 560 kg m?3. Temperature profiles over the reactor height were monitored online and ammonia emissions were measured periodically. The composition of the compost bed over the reactor height was determined at the end of the composting process. The composting process strongly depends on the density of the compost bed. At a density of 1100 kg.m?3, the porosity of the bed is too low to initiate natural convection, and aerobic degradation fails and anaerobic conditions may lead to emissions of methane and odorous compounds. At a density of 560 kg.m?3, the porosity of the bed is high and the high rate of natural convection will keep the temperature low thereby preventing the removal of pathogens and weeds. Best results were observed at a density of 700 kg.m?3 for which aerobic degradation and drying were adequate and temperatures were high enough to kill pathogens and weeds. On basis of the Ergun equation, which describes the airflow in porous media with internal heat generation, this corresponds to a compost bed permeability of 7×10?8 m2. It was also shown that it is possible to compost animal manures with a low C/N ratio without significant emissions of ammonia. This can be established by trapping the initial ammonia emissions in a straw filter, which is placed on top of the compost bed. Ammonia absorbed in the straw filter and in the compost bed were removed by nitrification and denitrification. The passively aerated composting system results in a compost bed which is highly heterogeneous with respect to temperature, oxygen level and its composition. It is proposed that in this way a highly diverse microbial community in the compost bed is established which can perform various microbial conversions. The extensive composting system is most promising for on-farm production of an organic fertilizer from straw-rich manure, since the costs of the process and the level of ammonia emissions were low. 相似文献
114.
Is humane slaughter of fish possible for industry? 总被引:4,自引:1,他引:4
Hans van de Vis Steve Kestin David Robb Jörg Oehlenschläger Bert Lambooij Werner Münkner Holmer Kuhlmann Karin Kloosterboer Margarita Tejada Almudena Huidobro Håkon Otterå Bjørn Roth Nils Kristian Sørensen Leif Akse Hazel Byrne & Paul Nesvadba 《Aquaculture Research》2003,34(3):211-220
Abstract The objective was to evaluate industrial and research slaughter methods for Atlantic salmon (Salmo salar), gilt‐head seabream (Sparus auratus) and eel (Anguilla anguilla) with respect to welfare and quality. As a general term of reference, an optimal slaughter method should render fish unconscious until death without avoidable excitement, pain or suffering prior to killing. For Atlantic salmon, commercial slaughter methods (carbon dioxide stunning followed by gill cutting, and gill cutting alone) are not in conformity with the general term of reference, as the fish are not rendered unconscious immediately and possibly experience stress. Evaluation of automated percussive stunning remained unconclusive. More research should enable us to ascertain whether loss of consciousness is instantaneous. Electrical stunning can be humane if applied properly. However, because flesh of electrostunned fish was characterized by occasional bloodspots, optimization of the electrical parameters is required. Prototypes for percussive and electrical stunning of salmon have been recently developed. This implies that humane slaughter of salmon is feasible for industry. For gilt‐head seabream, neither aphyxia in air nor transfer of the fish to an ice slurry were considered to be humane: the methods did not induce immediate brain dysfunction and vigorous attempts to escape occurred. Percussive and electrical stunning can be in conformity with the general term of reference. However, conditions for stunning whole batches of seabream have not been established. Quality of the fish slaughtered by percussive stunning was similar to that obtained by the industrial method, i.e. immersion in an ice slurry. Further work is required to establish optimal stunning conditions and to develop prototypes. For eel, desliming in a salt‐bath followed by evisceration, electrical stunning performed under the conditions prescribed by the German legislation, and live chilling and freezing were not considered to be humane. In contrast, it was established that a 10–20 kg batch of eels in fresh water could be rendered unconscious immediately and until death by applying electricity in combination with nitrogen gas. The conditions used were 0.64 A dm?2 for 1 s, followed by 0.17 A dm?2 combined with nitrogen flushing for 5 min. A preliminary assessment of flesh quality suggests that it may be improved by application of the latter method, compared with the salt bath. The results clearly indicated that humane slaughter of eels is possible in practice. 相似文献
115.
Agrawal N Frederick MJ Pickering CR Bettegowda C Chang K Li RJ Fakhry C Xie TX Zhang J Wang J Zhang N El-Naggar AK Jasser SA Weinstein JN Treviño L Drummond JA Muzny DM Wu Y Wood LD Hruban RH Westra WH Koch WM Califano JA Gibbs RA Sidransky D Vogelstein B Velculescu VE Papadopoulos N Wheeler DA Kinzler KW Myers JN 《Science (New York, N.Y.)》2011,333(6046):1154-1157
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type. 相似文献
116.
Field experiments were conducted in 1995, 1996, and 1997 at Agriculture and Agri-Food Canada’s Harrington Research Farm to assess the effect of whole seed tuber size and pre-plant seed storage conditions on processing yield (> 51 mm dia.) of potato (Solanum tuberosum L. cv Russet Burbank). Following commercial storage, seed tubers were stored at 4.4 C then subjected to one of three pre-plant treatments: (1) planted directly from storage, (2) held at 10 C for 3 wk before planting, or (3) green-sprouted for 3 wk before planting. Five sizes of whole seed were used (28, 42, 56, 70, and 84 g) with a variable size cut seed treatment added for comparison. Plots were harvested 138,134, and 131 days after planting in 1995, 1996, and 1997, respectively. Cut seed produced a higher yield of tubers > 51 mm diameter in comparison to all whole tuber seed sizes, with the exception of the 28 and 56 g sizes. In terms of total yield, the 28and 42-g whole seed tubers yielded significantly less than all other seed sizes examined. Warming or greensprouting seed tubers prior to planting did not increase tuber yield. The larger whole seed tuber sizes tended to result in greater numbers of stems and tubers per plant. To maximize marketable yield of Russet Burbank planted from whole seed tubers, it is recommended that the seed be between 28 and 42 g in size. Accepted for publication 25 May 2004. 相似文献
117.
Pamela Fonderie Cynthia de Vries Kirsten Verryken Richard Ducatelle Tom Moens Gunther van Loon Wim Bert 《Journal of Equine Veterinary Science》2013
A 5-year-old anorexic and lethargic Connemara mare presented with severe facial swelling and dyspnea. No distinct central nervous symptoms were present. Radiographs of the skull showed diffuse radiolucency with loss of definition of the periodontal lamina dura and swelling of the decalcified nasal bones. Given the severe bone damage and its poor general condition, the pony was euthanized. Histological evaluation of the lesion revealed a granulomatous reaction with numerous sections of adult and juvenile nematodes, which were morphologically and molecularly identified as Halicephalobus gingivalis. The position of this facultative parasite within its free-living congeners is reviewed in this article, and the possible infection routes are discussed. This report presents the first record of equine halicephalobiasis in Belgium. 相似文献
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119.
Jan G. van Logtestijn Bert A.P. Urlings Peter G.H. Bijker Jos H.J. Huis in ‘t Veld 《The Veterinary quarterly》2013,33(4):123-125
Summary Adverse reactions to various trimethoprim‐sulphonamide (T‐S) combinations were studied retrospectively in dogs and cats referred to the Utrecht University Department of Clinical Sciences of Companion Animals during the period 1985–1994. Dermatological and systemic reactions were observed in 19 dogs and 2 cats. Specific histological reaction patterns were seen in 3 dogs with toxic epidermal necrolysis, in 1 dog and 1 cat with erythema multiforme, and in 1 dog with pemphigus foliaceus. Diagnostic criteria used in humans proved to be reliable in dogs and cats as well. Adverse reactions were observed within 7–14 days after administration and were most often due to sulphadiazine (76%) and sulphatroxazole (14%). The incidence of adverse reactions to T‐S was 0.25%. 相似文献
120.
Ewa Gondek Ewa Jakubczyk Els Herremans Bert Verlinden Maarten Hertog Thomas Vandendriessche Pieter Verboven Aleksandra Antoniuk Evi Bongaers Pascal Estrade Bart M. Nicolaï 《Journal of Cereal Science》2013
The aim of this work was to describe the texture and structure of crisp bread obtained with different extrusion parameters. The texture of different crisp bread samples was evaluated using a combination of acoustic and mechanical tests. The advantage of this measurement setup is the feasibility of simultaneous registering of the force–deformation characteristics, sounds (using an acoustic envelope detector coupled to the texture analyser with a microphone) as well as mechanical vibrations (registered using a piezoelectric sensor) generated during a penetration test. All analysed samples of bread were products with a crisp texture that emitted audible sounds with a significant intensity that could be registered with a microphone as well as with a contact method. Micro-CT cross-section images showed the highly porous structure of the crisp breads but variant 3 appeared to have thicker walls and larger cells than the other breads. 相似文献