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1.
Towards sustainability in world fisheries 总被引:70,自引:0,他引:70
Pauly D Christensen V Guénette S Pitcher TJ Sumaila UR Walters CJ Watson R Zeller D 《Nature》2002,418(6898):689-695
Fisheries have rarely been 'sustainable'. Rather, fishing has induced serial depletions, long masked by improved technology, geographic expansion and exploitation of previously spurned species lower in the food web. With global catches declining since the late 1980s, continuation of present trends will lead to supply shortfall, for which aquaculture cannot be expected to compensate, and may well exacerbate. Reducing fishing capacity to appropriate levels will require strong reductions of subsidies. Zoning the oceans into unfished marine reserves and areas with limited levels of fishing effort would allow sustainable fisheries, based on resources embedded in functional, diverse ecosystems. 相似文献
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RK Koenekoop H Wang J Majewski X Wang I Lopez H Ren Y Chen Y Li GA Fishman M Genead J Schwartzentruber N Solanki EI Traboulsi J Cheng CV Logan M McKibbin BE Hayward DA Parry CA Johnson M Nageeb;Finding of Rare Disease Genes 《Nature genetics》2012,44(9):1035-1039
Leber congenital amaurosis (LCA) is a blinding retinal disease that presents within the first year after birth. Using exome sequencing, we identified mutations in the nicotinamide adenine dinucleotide (NAD) synthase gene NMNAT1 encoding nicotinamide mononucleotide adenylyltransferase 1 in eight families with LCA, including the family in which LCA was originally linked to the LCA9 locus. Notably, all individuals with NMNAT1 mutations also have macular colobomas, which are severe degenerative entities of the central retina (fovea) devoid of tissue and photoreceptors. Functional assays of the proteins encoded by the mutant alleles identified in our study showed that the mutations reduce the enzymatic activity of NMNAT1 in NAD biosynthesis and affect protein folding. Of note, recent characterization of the slow Wallerian degeneration (Wld(s)) mouse model, in which prolonged axonal survival after injury is observed, identified NMNAT1 as a neuroprotective protein when ectopically expressed. Our findings identify a new disease mechanism underlying LCA and provide the first link between endogenous NMNAT1 dysfunction and a human nervous system disorder. 相似文献
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Zusammenfassung Aus den Biberdrüsen wurdecis-Cyclohexan-1,2-diol isoliert und charakterisiert.
The support of this work by the Colombo Plan administration of Canada is gratefully acknowledged. 相似文献
The support of this work by the Colombo Plan administration of Canada is gratefully acknowledged. 相似文献
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A. Rashid 《Cellular and molecular life sciences : CMLS》1971,27(12):1498-1499
Zusammenfassung Nachweis, dass im LebermoosAsterella angusta erhöhte Saccharose-Konzentration Kallusgewebe induziert, welches sich in der Folge wieder ausdifferenziert, während Mannitzugabe zu stabilem Kallusgewebe führt. 相似文献
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Bell RD Winkler EA Singh I Sagare AP Deane R Wu Z Holtzman DM Betsholtz C Armulik A Sallstrom J Berk BC Zlokovic BV 《Nature》2012,485(7399):512-516
Human apolipoprotein E has three isoforms: APOE2, APOE3 and APOE4. APOE4 is a major genetic risk factor for Alzheimer's disease and is associated with Down's syndrome dementia and poor neurological outcome after traumatic brain injury and haemorrhage. Neurovascular dysfunction is present in normal APOE4 carriers and individuals with APOE4-associated disorders. In mice, lack of Apoe leads to blood-brain barrier (BBB) breakdown, whereas APOE4 increases BBB susceptibility to injury. How APOE genotype affects brain microcirculation remains elusive. Using different APOE transgenic mice, including mice with ablation and/or inhibition of cyclophilin A (CypA), here we show that expression of APOE4 and lack of murine Apoe, but not APOE2 and APOE3, leads to BBB breakdown by activating a proinflammatory CypA-nuclear factor-κB-matrix-metalloproteinase-9 pathway in pericytes. This, in turn, leads to neuronal uptake of multiple blood-derived neurotoxic proteins, and microvascular and cerebral blood flow reductions. We show that the vascular defects in Apoe-deficient and APOE4-expressing mice precede neuronal dysfunction and can initiate neurodegenerative changes. Astrocyte-secreted APOE3, but not APOE4, suppressed the CypA-nuclear factor-κB-matrix-metalloproteinase-9 pathway in pericytes through a lipoprotein receptor. Our data suggest that CypA is a key target for treating APOE4-mediated neurovascular injury and the resulting neuronal dysfunction and degeneration. 相似文献
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Nurul A. Yunus Mohd H. Ani Hamzah M. Salleh Rusila Z. A. Rashid Tomohiro Akiyama Hadi Purwanto Nur E. F. Othman 《矿物冶金与材料学报》2014,21(4):326-330
Beneficiation of Malaysian iron ore is becoming necessary as iron resources are depleting. However, the upgrading process is challenging because of the weak magnetic properties of Malaysian iron ore. In this study, bio-char derived from oil palm empty fruit bunch (EFB) was utilized as an energy source for reduction roasting. Mixtures of Malaysian iron ore and the bio-char were pressed into briquettes and subjected to reduction roasting processes at 873–1173 K. The extent of reduction was estimated on the basis of mass loss, and the magnetization of samples was measured using a vibrating sample magnetometer (VSM). When reduced at 873 K, the original goethite-rich ore was converted into hematite. An increase in temperature to 1073 K caused a significant conversion of hematite into magnetite and enhanced the magnetic susceptibility and saturation magnetization of samples. The magnetic properties diminished at 1173 K as the iron ore was partially reduced to wustite. This reduction roasting by using the bio-char can assist in upgrading the iron ore by improving its magnetic properties. 相似文献
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AbdurRashid GhulamMustafa 《中国科学技术大学学报》2003,33(5):547-554
采用带限制算子的傅立叶拟谱方法近似求解了Burgers方程,分别证明了它的(Burgers方程)一般化的稳定性和收敛性,并获得了数值结果. 相似文献
10.
Yusa K Rashid ST Strick-Marchand H Varela I Liu PQ Paschon DE Miranda E Ordóñez A Hannan NR Rouhani FJ Darche S Alexander G Marciniak SJ Fusaki N Hasegawa M Holmes MC Di Santo JP Lomas DA Bradley A Vallier L 《Nature》2011,478(7369):391-394
Human induced pluripotent stem cells (iPSCs) represent a unique opportunity for regenerative medicine because they offer the prospect of generating unlimited quantities of cells for autologous transplantation, with potential application in treatments for a broad range of disorders. However, the use of human iPSCs in the context of genetically inherited human disease will require the correction of disease-causing mutations in a manner that is fully compatible with clinical applications. The methods currently available, such as homologous recombination, lack the necessary efficiency and also leave residual sequences in the targeted genome. Therefore, the development of new approaches to edit the mammalian genome is a prerequisite to delivering the clinical promise of human iPSCs. Here we show that a combination of zinc finger nucleases (ZFNs) and piggyBac technology in human iPSCs can achieve biallelic correction of a point mutation (Glu342Lys) in the α(1)-antitrypsin (A1AT, also known as SERPINA1) gene that is responsible for α(1)-antitrypsin deficiency. Genetic correction of human iPSCs restored the structure and function of A1AT in subsequently derived liver cells in vitro and in vivo. This approach is significantly more efficient than any other gene-targeting technology that is currently available and crucially prevents contamination of the host genome with residual non-human sequences. Our results provide the first proof of principle, to our knowledge, for the potential of combining human iPSCs with genetic correction to generate clinically relevant cells for autologous cell-based therapies. 相似文献