Ecology of Plant-Derived Smoke: Its Use in Seed Germination     

Marnie E Light 《African Journal of Range and Forage Science》2016,33(1)

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Insect chemical ecology research in the United States Department of Agriculture-Agricultural Research Service     

Aldrich JR  Bartelt RJ  Dickens JC  Knight AL  Light DM  Tumlinson JH 《Pest management science》2003,59(6-7):777-787

This multi-author paper reviews current work by USDA-ARS scientists in the field of chemical ecology. Work with pheromones, the discovery and development of the codling moth kairomone, studies on insect-plant interactions and chemically mediated tritrophic plant-insect interactions have led to practical methods for control of important insect pests.  相似文献   

Acanthocephalan infection and sparganosis in a green tree snake (Dendrelaphis punctulata)     

AG Hill  PW Ladds  DM Spratt 《Australian veterinary journal》2014,92(9):362-364

Acanthocephalan and spargana parasites were identified within a body wall mass during exploratory surgery in a wild green tree snake. Acanthocephalan parasites have not previously been reported in this species. Surgical excision, the treatment of choice, could not be achieved because of the extensive infiltration of the coelomic cavity.  相似文献   

Probing the Local Effects of Magnetic Impurities on Superconductivity     

A Yazdani  BA Jones  CP Lutz  MF Crommie  DM Eigler 《Science (New York, N.Y.)》1997,275(5307):1767-1770

The local effects of isolated magnetic adatoms on the electronic properties of the surface of a superconductor were studied with a low-temperature scanning tunneling microscope. Tunneling spectra obtained near magnetic adsorbates reveal the presence of excitations within the superconductor's energy gap that can be detected over a few atomic diameters around the impurity at the surface. These excitations are locally asymmetric with respect to tunneling of electrons and holes. A model calculation based on the Bogoliubov-de Gennes equations can be used to understand the details of the local tunneling spectra.  相似文献   

Spontaneous formation of macroscopic chiral domains in a fluid smectic phase of achiral molecules     

DR Link  G Natale  R Shao  JE Maclennan  NA Clark  E Korblova  DM Walba 《Science (New York, N.Y.)》1997,278(5345):1924-1927

A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field-induced transition from antiferroelectric to ferroelectric.  相似文献   

Organic Glasses: A New Class of Photorefractive Materials     

PM Lundquist  R Wortmann  C Geletneky  RJ Twieg  M Jurich  VY Lee  CR Moylan  DM Burland 《Science (New York, N.Y.)》1996,274(5290):1182-1185

The performance of amorphous organic photorefractive (PR) materials in applications such as optical data storage is generally limited by the concentration of active molecules (chromophores) that can be incorporated into the host without forming a crystalline material with poor optical quality. In polymeric PR systems described previously, performance has been limited by the necessity of devoting a large fraction of the material to inert polymer and plasticizing components in order to ensure compositional stability. A new class of organic PR materials composed of multifunctional glass-forming organic chromophores is described that have long-term stability and greatly improved PR properties.  相似文献   

Atrial natriuretic peptide inhibits a cation channel in renal inner medullary collecting duct cells   总被引：18，自引：0，他引：18  

D B Light  E M Schwiebert  K H Karlson  B A Stanton 《Science (New York, N.Y.)》1989,243(4889):383-385

The patch-clamp technique was used to examine the effects of atrial natriuretic peptide (ANP) and its second messenger guanosine 3',5'-monophosphate (cGMP) on an amiloride-sensitive cation channel in the apical membrane of renal inner medullary collecting duct cells. Both ANP (10(-11) M) and dibutyryl guanosine 3',5'-monophosphate (10(-4) M) inhibited the channel in cell-attached patches, and cGMP (10(-5) M) inhibited the channel in inside-out patches. The inner medullary collecting duct is the first tissue in which ANP, via its second messenger cGMP, has been shown to regulate single ion channels. The results suggest that the natriuretic action of ANP is related in part to cGMP-mediated inhibition of electrogenic Na+ absorption by the inner medullary collecting duct.  相似文献   

Nanofabrication of Small Copper Clusters on Gold(111) Electrodes by a Scanning Tunneling Microscope     

DM Kolb  R Ullmann  T Will 《Science (New York, N.Y.)》1997,275(5303):1097-1099

The use of scanning tunneling microscopy in an electrochemical environment as a tool for the nanoscale modification of gold electrodes was demonstrated. Small copper clusters, typically two to four atomic layers in height, were precisely positioned on a gold(111) electrode by a process in which copper was first deposited onto the tip of the scanning tunneling microscope, which then acted as a reservoir from which copper could be transferred to the surface during an appropriate approach of the tip to the surface. Tip approach and position were controlled externally by a microprocessor unit, allowing the fabrication of various patterns, cluster arrays, and "conducting wires" in a very flexible and convenient manner.  相似文献   

Specificity of codling moth (Lepidoptera: Tortricidae) for the host plant kairomone, ethyl (2E,4Z)-2,4-decadienoate: field bioassays with pome fruit volatiles, analogue, and isomeric compounds     

Light DM  Knight A 《Journal of agricultural and food chemistry》2005,53(10):4046-4053

Codling moth, Cydia pomonella (L.), is a severe pest of apples, pears, and walnuts worldwide, and new approaches for precise monitoring and management would be beneficial. Ninety-two pome fruit volatiles were formulated in 23 distinct blends, of which a single 4-component blend of 10-carbon esters showed the only significant attraction of moths in field bioassays conducted in both walnut and apple orchards. A single constituent of this blend, ethyl (2E,4Z)-2,4-decadienoate--the "pear ester", was the major contributing attractant. The pear ester attracted both male and female moths in combined numbers that were comparable to the attractiveness of conspecific sex pheromone. Structure-activity tests were conducted in a series of orchard trials to determine the specificity of attraction of codling moths to the pear ester kairomone. No analogue 10-carbon alcohols, aldehydes, acetates, or other esters elicited significant moth capture responses. Tests with various analogue esters with alcohol chain length moiety substitutions of the (2E,4Z)-2,4-decadienoic acid elicited differential capture responses, with the ethyl exceeding the propyl, methyl, butyl, and hexyl analogues. The (E,Z) geometric isomers of this series of (2E,4Z)-2,4-decadienoic acid esters far exceeded the attractiveness of the (E,E) isomers. The pear ester is a potent attractant of both males and females, and codling moths are highly discriminating and specific in their structure-activity-based attraction to this pear-derived kairomone. These specificity attributes should allow this host plant kairomone to contribute to new abilities for female monitoring and the potential of development of novel and highly selective control practices that should decrease the current dependence on the use of broad-spectrum insecticides.  相似文献   

THE EFFECT OF ARTIFICIAL DEFOLIATION OF PEA PLANTS ON THE YIELD OF SHELLED PEAS   总被引：1，自引：1，他引：0  

K. S. George  W. I. St. G.  Light R. Gair 《Plant pathology》1962,11(2):73-80

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