Photoperiod manipulation of insect diapause: a method of pest control?   总被引：3，自引：0，他引：3  

D K Hayes  W N Sullivan  M Z Oliver  M S Schechter 《Science (New York, N.Y.)》1970,169(943):382-383

Extension of day length by artificial light in selected field plots in the fall prevented 76 percent of European corn borer [Ostrinia nubilalis (Hübner)] larvae and 70 percent of codling moth [Laspeyresia pomonella (L.)] larvae from entering diapause. Nondiapausing insects cannot survive rigorous winter conditions.  相似文献   

Hypertensive action of 18-hydroxydeoxycorticosterone   总被引：2，自引：0，他引：2  

J T Oliver  M K Birmingham  A Bartova  M P Li  T H Chan 《Science (New York, N.Y.)》1973,182(118):1249-1251

18-Hydroxydeoxycorticosterone is an adrenal steroid hormone causing salt and water retention and is secreted in greatly increased amounts in response to the pituitary hormone adrenocorticotropic hormone. Its production is abnormally high in some forms of hypertension in man and rat. Direct proof that 18-hydroxydeoxycorticosterone is capable of causing hypertension is present. Daily subcutaneous injections of 200 micrograms, a low physiological dose, significantly increase the blood pressure of unilaterally nephrectomized saline-treated rats after 2 weeks. This strengthens the hypothesis that 18-hydroxydeoxycorticosterone contributes to the etiology of hypertension, possibly by a mechanism involving stressinduced release of adrenocorticotropic hormone.  相似文献   

Amygdalar and hippocampal theta rhythm synchronization during fear memory retrieval     

Seidenbecher T  Laxmi TR  Stork O  Pape HC 《Science (New York, N.Y.)》2003,301(5634):846-850

The amygdalohippocampal circuit plays a pivotal role in Pavlovian fear memory. We simultaneously recorded electrical activity in the lateral amygdala (LA) and the CA1 area of the hippocampus in freely behaving fear-conditioned mice. Patterns of activity were related to fear behavior evoked by conditioned and indifferent sensory stimuli and contexts. Rhythmically synchronized activity at theta frequencies increased between the LA and the CA1 after fear conditioning and became significant during confrontation with conditioned fear stimuli and expression of freezing behavior. Synchronization of theta activities in the amygdalohippocampal network represents a neuronal correlate of conditioned fear, apt to improve neuronal communication during memory retrieval.  相似文献   

Atmospheric lines in the solar spectrum     

Oliver JE 《Science (New York, N.Y.)》1887,9(206):33-34

  相似文献   

Prevention of vaginal SHIV transmission in rhesus macaques through inhibition of CCR5   总被引：1，自引：0，他引：1  

Lederman MM  Veazey RS  Offord R  Mosier DE  Dufour J  Mefford M  Piatak M  Lifson JD  Salkowitz JR  Rodriguez B  Blauvelt A  Hartley O 《Science (New York, N.Y.)》2004,306(5695):485-487

Topical agents, such as microbicides, that can protect against human immunodeficiency virus (HIV) transmission are urgently needed. Using a chimeric simian/human immunodeficiency virus (SHIV SF162), which is tropic for the chemokine receptor CCR5, we report that topical application of high doses of PSC-RANTES, an amino terminus-modified analog of the chemokine RANTES, provided potent protection against vaginal challenge in rhesus macaques. These experimental findings have potentially important implications for understanding vaginal transmission of HIV and the design of strategies for its prevention.  相似文献   

Electron tunneling through organic molecules in frozen glasses     

Wenger OS  Leigh BS  Villahermosa RM  Gray HB  Winkler JR 《Science (New York, N.Y.)》2005,307(5706):99-102

Reaction rates extracted from measurements of donor luminescence quenching by randomly dispersed electron acceptors reveal an exponential decay constant of 1.23 per angstrom for electron tunneling through a frozen toluene glass (with a barrier to tunneling of 1.4 electron volts). The decay constant is 1.62 per angstrom (the barrier, 2.6 electron volts) in a frozen 2-methyl-tetrahydrofuran glass. Comparison to decay constants for tunneling across covalently linked xylyl (0.76 per angstrom) and alkyl (1.0 per angstrom) bridges leads to the conclusion that tunneling between solvent molecules separated by approximately 2 angstroms (van der Waals contact) is 20 to 50 times slower than tunneling through a comparable length of a covalently bonded bridge. Our results provide experimental confirmation that covalently bonded pathways can facilitate electron flow through folded polypeptide structures.  相似文献   

Evolution of oxygen secretion in fishes and the emergence of a complex physiological system     

Berenbrink M  Koldkjaer P  Kepp O  Cossins AR 《Science (New York, N.Y.)》2005,307(5716):1752-1757

We have reconstructed the events that led to the evolution of a key physiological innovation underpinning the large adaptive radiation of fishes, namely their unique ability to secrete molecular oxygen (O2). We show that O2 secretion into the swimbladder evolved some 100 million years after another O2-secreting system in the eye. We unravel the likely sequence in which the functional components of both systems evolved. These components include ocular and swimbladder countercurrent exchangers, the Bohr and Root effects, the buffering power and surface histidine content of hemoglobins, and red blood cell Na+/H+ exchange activity. Our synthesis reveals the dynamics of gains and losses of these multiple traits over time, accounting for part of the huge diversity of form and function in living fishes.  相似文献   

A C. elegans CLIC-like protein required for intracellular tube formation and maintenance     

Berry KL  Bülow HE  Hall DH  Hobert O 《Science (New York, N.Y.)》2003,302(5653):2134-2137

The Caenorhabditis elegans excretory canal is composed of a single elongated and branched cell that is tunneled by an inner lumen of apical character. Loss of the exc-4 gene causes a cystic enlargement of this intracellular tube. exc-4 encodes a member of the chloride intracellular channel (CLIC) family of proteins. EXC-4 protein localizes to various tubular membranes in distinct cell types, including the lumenal membrane of the excretory tubes. A conserved 55-amino acid domain enables EXC-4 translocation from the cytosol to the lumenal membrane. The tubular architecture of this membrane requires EXC-4 for both its formation and maintenance.  相似文献   

Paucity of genes on the Drosophila X chromosome showing male-biased expression     

Parisi M  Nuttall R  Naiman D  Bouffard G  Malley J  Andrews J  Eastman S  Oliver B 《Science (New York, N.Y.)》2003,299(5607):697-700

Sex chromosomes are primary determinants of sexual dimorphism in many organisms. These chromosomes are thought to arise via the divergence of an ancestral autosome pair and are almost certainly influenced by differing selection in males and females. Exploring how sex chromosomes differ from autosomes is highly amenable to genomic analysis. We examined global gene expression in Drosophila melanogaster and report a dramatic underrepresentation of X-chromosome genes showing high relative expression in males. Using comparative genomics, we find that these same X-chromosome genes are exceptionally poorly conserved in the mosquito Anopheles gambiae. These data indicate that the X chromosome is a disfavored location for genes selectively expressed in males.  相似文献   

Mercury: observations of the 3.4-millimeter radio emission     

Epstein EE  Soter SL  Oliver JP  Schorn RA  Wilson WJ 《Science (New York, N.Y.)》1967,157(3796):1550-1552

Observations of the 3.4-millimeter radio emission from Mercury during 1965 and 1966 yielded the following relationship between average brightness temperature T(B) of the disk and the planetocentric phase angle i: T(B) = 277 (+/- 12) + 97 (+/- 17) cos [i + 29 deg (+/- 10 deg)] degrees K The errors are statistical standard; the phase shift corresponds to a phase lag-that is, the maximum and minimum of insolation lag the maximum and minimum of planetary radiation.  相似文献