Purification and characterization of an antibacterial compound produced by Agrobacterium vitis strain E26 with activity against A. tumefaciens     

H. M. Wang  H. X. Wang  T. B. Ng †  J. Y. Li 《Plant pathology》2003,52(2):134-139

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Canine and feline cutaneous screw‐worm myiasis in Malaysia: clinical aspects in 76 cases          下载免费PDF全文

Hock Siew Han  Peik Yean Toh  Hock Binn Yoong  Hooi Meng Loh  Lee Lee Tan  Yin Yin Ng 《Veterinary dermatology》2018,29(5):442-e148

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Thermal effects on water retention behaviour of unsaturated collapsible loess     

Cheng  Qing  Zhou  Chao  Ng  Charles Wang Wao  Tang  Chaosheng 《Journal of Soils and Sediments》2020,20(2):756-762

Journal of Soils and Sediments - Temperature has a significant influence on water retention curve (WRC) because temperature affects surface tension of water and volumetric behaviour of soil....  相似文献   

Atomic absorption spectrophotometric determination of selenium in animal feed premix, using the vapor generation technique.     

S Ng  W McSharry 《Journal of the Association of Official Analytical Chemists》1975,58(5):987-989

An atomic absorption spectrophotometric method, using the vapor generation technique for the determination of selenium in animal feed premixes containing 0.4-0.002% selenium, is described. After the sample was digested in perchloric acid and hydrogen peroxide and reduced with 6M HCl, 3 aliquots of sample, each containing about 0.4 mug Se, were taken for analysis by the standard addition method. Sodium borohydride pellets were used for the generation of selenium hydride. The relative standard deviation of a single determination averaged +/- 19%.  相似文献   

The conservation status of the Nee Soon freshwater swamp forest of Singapore     

Peter K. L. Ng  Kelvin K. P. Lim 《水产资源保护:海洋与淡水生态系统》1992,2(3):255-266

1. The most important area in Singapore for native aquatic fauna and flora is a relatively intact 5 km² patch of freshwater swamp forest in Nee Soon. 2. The Nee Soon Swamp Forest contains 48% of the primary freshwater fish, 71% of the amphibian, 28% of the reptile and 34% of the bird fauna of Singapore. The swamp also has the highest percentage of native and threatened freshwater fish and crustacean species on the island, as well as being the main (if not the only) habitat of the aquatic plant Hydrostemma. It is also the last refuge of two mammals, the Banded Leaf Monkey, Presbytis femoralis femoralis, and the Cream-coloured Giant Squirrel, Ratufa affinis affinis. 3. The threats to the swamp forest are discussed, and proposals are made to establish the swamp forest as Singapore's second major nature reserve. 4. Study of the swamp forest is essentially still at a survey and discovery phase. The research priorities are to establish detailed species lists, the status of endangered species and the extent of buffer zones. 5. The swamp forest is administered primarily by the newly established National Parks Board, but several other government organizations also have jurisdiction over the land, causing some problems in the management of the swamp. The roles of the university and non-governmental organizations in conducting surveys, drafting recommendations and educating the general public are detailed.  相似文献   

Digital mapping of soil carbon sequestration potential with enhanced vegetation cover over New South Wales,Australia     

Jonathan M. Gray  Bin Wang  Cathleen M. Waters  Susan E. Orgill  Annette L. Cowie  Ee Ling Ng 《Soil Use and Management》2022,38(1):229-247

Digital soil maps of soil organic carbon (SOC) sequestration potential resulting from a hypothetical 10% relative increase in long-term vegetation cover are presented at 100-m resolution across the state of New South Wales (NSW) in southeast Australia. This land management outcome is considered realistically achievable for many land managers, using strategies such as revegetation, grazing management or crop residue management. A mean state-wide potential increase of 5.4 Mg ha⁻¹ over the 0- to 30-cm depth interval was derived. Assuming a 20-year period of re-equilibration, this equates to an average SOC increase of 0.27 Mg ha⁻¹ year⁻¹. Sequestration potential is systematically influenced by a combination of climate, soil parent material and current vegetation cover, for example only 1.6 Mg ha⁻¹ SOC under dry conditions in sandy, infertile soil material with sparse vegetation cover, compared with 15.9 Mg ha⁻¹ under wet conditions in clay-rich, fertile soil material with moderate–high vegetation cover. The outputs could be used to identify locations of highest sequestration potential and thereby help prioritize areas and inform decisions on sequestration programmes. Future application of the method at field scale with high levels of accuracy, together with strategic sampling, may provide statistically reliable estimates of carbon sequestration, for application in carbon trading schemes such as Australia's Emissions Reduction Fund. The modelling involved a conceptually transparent ‘space-for-time substitution’ process. Multiple linear regression (MLR) and random forest (RF) modelling techniques were applied, but only MLR gave consistently meaningful results. The apparent failing of RF in this application warrants further examination.  相似文献   

Feeding ecology of the blacktip sawtail catshark Galeus sauteri from northeastern Taiwan     

Ng  Shing-Lai  Joung  Shoou-Jeng 《Fisheries Science》2022,88(6):703-720

Small-bodied sharks are recognized as mesopredators on different communities in a large variety of habitats, thus linking the trophic levels in the marine ecosystem. Dietary analysis on these species can provide insight into the trophic relationships in food webs. Our study analyzed the diet composition of Galeus sauteri, an abundant small shark inhabiting neritic shelf waters at depths between 60 and 200 m. For this purpose, a stomach content analysis was realized in 678 specimens collected by bottom trawlers off northeastern Taiwan from September 2018 to August 2019. The two most commonly consumed preys were teleosts (prey-specific index of relative importance, %PSIRI?=?51.94) and crustaceans (%PSIRI?=?30.08).The results for the Levin’s index (Ba?=?0.06) and graphical analysis based on the Costello method revealed a high degree of specialization on lanternfishes and other teleosts. The mean trophic position was 4.29. Feeding habits differed significantly in relation to maturity condition and between seasons. Our result showed that G. sauteri is a primary piscivorous shark that preys mainly on lanternfishes and other teleosts, and feeds opportunistically on crustaceans and cephalopods.

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Identification of odorous gases originating from refuse waste     

Lawrence C. C. Koe  W. J. Ng 《Water, air, and soil pollution》1987,33(1-2):199-204

The complex mixture of gaseous compounds emitted from refuse wastes was scrubbed through an activated carbon column until odor breakthrough occurred. Refuse air samples were collected at the influent and effluent ports of the column for analysis on a gas chromatograph-mass spectrometer system. Sampling techniques involved the concentration of gaseous volatiles on Tenax GC adsorption tubes prior to thermal desorption onto a capillary fused-silica column for compound separation. Separated compounds were scanned by a quadrapole mass selective detector and compounds were matched against a library of mass spectra and available gas standards. Results indicated that the typical odorous gases emitted from refuse waste consisted mainly of carboxylic acids and some S compounds. Sensory tests revealed that a sweetish odor was associated with the carboxylic acids which eluted from the carbon column first.  相似文献   

Physicochemical characteristics of onion (Allium cepa L.) tissues     

Ng A  Parker ML  Parr AJ  Saunders PK  Smith AC  Waldron KW 《Journal of agricultural and food chemistry》2000,48(11):5612-5617

The structure and mechanical properties of onions are important factors affecting their textural quality. The onion bulb consists of several layers of pigmented, papery scales surrounding fleshy storage scales that comprise an upper epidermis, an intermediate parenchyma tissue, and a lower epidermis. The purpose of this study was to examine the chemical composition of cell walls from the papery scales and outer fleshy scales of onion (Allium cepa L. cv. Sturon) in relation to their mechanical properties. Cell-wall material (CWM) was prepared from the component tissues and analyzed for its carbohydrate and phenolic composition. The CWMs were rich in uronic acid and glucose, with smaller quantities of arabinose, galactose, and xylose. In the fleshy scales, the lower epidermis contained relatively more galactose-rich pectic polysaccharides, whereas the upper epidermis and the papery scales contained virtually no galactose. Analysis of mechanical properties showed that the order of strength of the tissues was papery scales > fleshy scales, which were in the order lower epidermis > upper epidermis > intermediate parenchyma. The upper epidermis of fleshy scales was stronger in the vertical than the horizontal direction, and both orientations showed negligible notch sensitivity. Cyclohexane-trans-1,2-diaminetetraacetate-induced vortex-induced cell separation of the intermediate layer of fleshy scales indicated that calcium cross-linking may play an important role in cell-cell adhesion. A small but significant amount of ferulic acid was found in the walls, predominantly in the thick cuticle of the lower epidermis of fleshy scales. Alkali-labile wall-bound flavonoids were also detected.  相似文献   

Cloning of complementary DNA for GAP-43, a neuronal growth-related protein   总被引：33，自引：0，他引：33  

L R Karns  S C Ng  J A Freeman  M C Fishman 《Science (New York, N.Y.)》1987,236(4801):597-600

GAP-43 is one of a small subset of cellular proteins selectively transported by a neuron to its terminals. Its enrichment in growth cones and its increased levels in developing or regenerating neurons suggest that it has an important role in neurite growth. A complementary DNA (cDNA) that encodes rat GAP-43 has been isolated to study its structural characteristics and regulation. The predicted molecular size is 24 kilodaltons, although its migration in SDS-polyacrylamide gels is anomalously retarded. Expression of GAP-43 is limited to the nervous system, where its levels are highest during periods of neurite outgrowth. Nerve growth factor or adenosine 3',5'-monophosphate induction of neurites from PC12 cells is accompanied by increased GAP-43 expression. GAP-43 RNA is easily detectable, although at diminished levels, in the adult rat nervous system. This regulation of GAP-43 is concordant with a role in growth-related processes of the neuron, processes that may continue in the mature animal.  相似文献