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排序方式: 共有393条查询结果,搜索用时 15 毫秒
1.
In many disaster settings, top‐down responses emphasise ‘expert‐led’ solutions that often involve relocating disaster‐affected communities. While the intention might be to move people from harm's way and facilitate recovery, failure to attend to local pre‐disaster circumstances as well as the interplay between power, resilience and vulnerability within and around affected communities often sees resettlement reconfigure as displacement or disconnection. This oversight may even usher in a new phase of dispossession and disadvantage for marginalised groups (particularly in colonial settings). This paper explores experiences in Australia, Japan and Taiwan to reflect on what issues of local sociality, local culture and local resilience need to be attended to in framing ‘better’ disaster responses. 相似文献
2.
Paddy and Water Environment - This study proposes a risk analysis model for quantifying the insufficient risk of rice production due to the climate change and variation in irrigation water and... 相似文献
3.
Summary Inheritance of yield and its component (number of ears per plant, number of spikelets per ear, number of kernels per ear, 1000-kernel weight), together with the inheritance of morphological characters (flag leaf length, flag leaf breadth, peduncle length, extrusion length and leaf sheath length) and anthesis date was studied in a 5-parent diallel cross of spring wheat varieties. The diallel analysis of gene actions indicated that a large part of the total genetic variation observed for all the characters studied was in the form of additive genetic effects. The degree of dominance was also determined for each character. Number of ears per plant showed most overdominance, followed by leaf sheath length. Full or nearly full dominance was found for anthesis date, flag leaf length and yield per plant. Other characters showed partial dominance. Correlation coefficients showed that yield per plant, as well as being correlated with the yield components, was also assiciated with flag leaf breadth and leaf sheath length. There was no evidence of genetic barriers to the combining of ideal characters among the varieties of different origin. 相似文献
4.
5.
On mechanical behavior of traditional timber shear wall in Taiwan I: background and theory derivation 总被引:1,自引:0,他引:1
The objectives of this study were to explore the mechanical behavior of traditional timber shear walls in Taiwan and to propose
a theoretical model to predict their lateral force resistance. An extensive field investigation was conducted, and the dimensions,
tectonic detail, and materials used were recorded. The data collected were used as the reference for theoretical derivation
and experimental design. In the theoretical model, the moment resistance of entire shear walls was derived from the contributions
of the moment-resisting capacity supplied not only by embedment and friction action between board units and beams but also
the dowel action of bamboo nails. Timber shear walls with various geometric conditions and material properties are considered.
The theoretical model demonstrated in this study can be used to predict the mechanical behavior of timber shear walls and
will be verified by experiments in our next article. 相似文献
6.
Summary The deformation and stresses in a circular wood log resulting from an arbitrary radial moisture distribution are examined. In this paper the log is modeled as a layered cylinder, with each layer assumed to be linearly elastic, cylindrically orthotropic, and homogeneous. The general solution to the equations of elasticity for a representative layer is given; constants of integration in the solution are determined through application of appropriate continuity conditions at the layer interfaces. Numerical examples are presented for logs of Scots pine which illustrate the effect of nonuniform moisture content upon the displacement and stress distributions. 相似文献
7.
Hsu FL Lin YH Lee MH Lin CL Hou WC 《Journal of agricultural and food chemistry》2002,50(21):6109-6113
Dioscorin, the tuber storage protein of yam (Dioscorea alata cv. Tainong No. 1), was purified to homogeneity by DE-52 ion-exchange chromatography. This purified dioscorin was shown by spectrophotometric methods to inhibit angiotensin converting enzyme (ACE) in a dose-dependent manner (12.5-750 microg, respectively, 20.83-62.5% inhibitions) using N-[3-(2-furyl)acryloyl]-Phe-Gly-Gly (FAPGG) as substrates. The 50% inhibition (IC(50)) of ACE activity was 6.404 microM dioscorin (250 microg corresponding to 7.81 nmol) compared to that of 0.00781 microM (0.0095 nmol) for captopril. The commercial bovine serum albumin and casein (bovine milk) showed less ACE inhibitory activity. The use of qualitative TLC also showed dioscorin as ACE inhibitors. Dioscorin showed mixed noncompetitive inhibitions against ACE; when 31.25 microg of dioscorin (0.8 microM) was added, the apparent inhibition constant (K(i)) was 2.738 microM. Pepsin was used for dioscorin hydrolysis at 37 degrees C for different times. It was found that the ACE inhibitory activity was increased from 51.32% to about 75% during 32 h hydrolysis. The smaller peptides were increased with increasing pepsin hydrolytic times. Dioscorin and its hydrolysates might be a potential for hypertension control when people consume yam tuber. 相似文献
8.
9.
Obesity is an important topic in the world of public health and preventive medicine. Inhibition of preadipocyte proliferation plays an important role in the mechanisms of proposed antiobesity. In this in vitro study, the inhibitory effect of phenolic acids on 3T3-L1 preadipocytes was evaluated, and a relationship analysis was then conducted. The results showed that the addition of phenolic acids to the growth medium decreased the cell population growth of 3T3-L1 preadipocytes. The IC50 values of chlorogenic acid, gallic acid, o-coumaric acid and m-coumaric acid on 3T3-L1 preadipocytes were 72.3, 43.3, 48.2, and 49.2 microM, respectively. A relationship analysis indicated that there is a significant linear correlation between the influence of phenolic acids on cell population growth and their antioxidant activity (r = 0.77, p < 0.01). The cell cycle assay indicated that the treatment of 3T3-L1 preadipocytes with chlorogenic acid, o-coumaric acid, and m-coumaric acid caused cell cycle arrest in the G1 phase. Gallic acid did not affect the cell cycle profile; however, it increased the number of apoptotic cells (sub-G1 phase) in a time- and dose-dependent manner. Annexin V-fluorescein isothiocyanate (FITC)-propidium iodide (PI) apoptosis flow cytometric assay showed that gallic acid increased the number of early apoptotic (annexin V-FITC+/PI-) and late apoptotic cells (annexin V-FITC+/PI+) but not necrotic cells (annexin V-FITC-/PI+). The treatment of cells with gallic acid caused the loss of mitochondrial membrane potential (delta psi(m)). These results indicate that the inhibition of preadipocyte population growth by some phenolic acids might have further implication in in vivo antiobesity effects. 相似文献
10.
New dammarane-type saponins from the galls of Sapindus mukorossi 总被引:2,自引:0,他引:2
Kuo YH Huang HC Yang Kuo LM Hsu YW Lee KH Chang FR Wu YC 《Journal of agricultural and food chemistry》2005,53(12):4722-4727
Five new dammarane-type saponins, 3beta,7beta,20(S),22-tetrahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,23-pentahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,25-pentahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 25-methoxy-3beta,7beta,20(S),22-tetrahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, and 25-methoxy-3beta,7beta,20(R)-trihydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, named sapinmusaponins A (1), B (2), C (3), D (4), and E (5), respectively, together with three known phenylpropanoid glycosides (6-8), were isolated from the galls of Sapindus mukorossi. The structures of these saponins were elucidated on the basis of spectroscopic analyses and chemical methods. Preliminary bioassay data revealed that saponins 1 and 3-5 showed moderate cytotoxic activity (ED50 approximately 9-18 microg/mL) against human tumor cell lines (Hepa59T/VGH, NCI, HeLa, and Med) and that 1-5 were inactive in vitro against HIV replication in H9 lymphocytes. 相似文献