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71.
LAURA M. BOYKIN RUTH ANN BAGNALL DONALD R. FROHLICH DAVID G. HALL WAYNE B. HUNTER CATHERINE S. KATSAR CINDY L. MCKENZIE ROSEMARIE C. ROSELL ROBERT G. SHATTERS JR. 《Molecular ecology resources》2007,7(6):1202-1204
Twelve polymorphic microsatellite markers were developed from microsatellite‐enriched DNA libraries and mined from an expressed sequence tags library of Diaphorina citri, the vector of the citrus greening disease (huanglongbing). Analysis of 288 individuals from Florida, Texas, and Brazil showed that allelic diversity ranged from three to eight alleles per locus and observed and expected heterozygosities ranged from 0.014 to 0.569 and from 0.052 to 0.653, respectively. These variable microsatellite loci can provide means for assessing overall genetic variation and migration patterns for this agriculturally important pest species. This information can be used to aid in developing successful management strategies. 相似文献
72.
SHOIL M. GREENBERG GRETCHEN D. JONES FRANK EISCHEN RANDY J. COLEMAN JOHN J. ADAMCZYK JR. TONG-XIAN LIU MAMOUDOU SETAMOU 《Insect Science》2007,14(6):503-510
The survival of overwintering boll weevil, Anthonomus grandis grandis (Boheman), adults on non-cotton hosts in the Lower Rio Grande Valley (LRGV) of Texas was examined from 2001 to 2006. The success of the Boll Weevil Eradication Program, which was reintroduced into the LRGV in 2005, depends on controlling overwintering boll weevil populations. Laboratory studies were conducted using boll weevil adults that were captured in pheromone traps from September through March. The number of adults captured per trap declined significantly in the field from fall to the beginning of spring (3.5-7.0-fold). The proportion of trapped males and females did not differ significantly. The mean weight of boll weevil adults captured in September was 13.3 mg, while those of captured adults from November to February were significantly lower and ranged from 6.7 to 7.8 mg. Our results show that boll weevil adults can feed on different plant pollens. The highest longevity occurred when adults were fed almond pollen or mixed pollens (72.6 days and 69.2 days, respectively) and the lowest when they fed on citrus pollen or a non-food source (9.7 days or 7.4 days, respectively). The highest adult survival occurred on almond and mixed pollens [88.0%-97. 6% after 1st feeding period (10 days), 78.0%-90.8% after 3rd feeding period (10 days), 55. 0%-83.6% after 5th feeding period (10 days), and 15.2%-32.4% after lOth feeding period (10 days)]. The lowest adult survival occurred on citrus pollen [52.0%-56.0% after 1st feeding period (10 days), 13.3% after 3rd and 5th feeding periods (10 days), and 0 after 6th feeding period (10 days)]. Pollen feeding is not a behavior restricted to adult boll weevils of a specific sex or physiological state. Understanding how boll weevil adults survive in the absence of cotton is important to ensure ultimate success of eradicating this pest in the subtropics. 相似文献
73.
Ant inquilines are obligate social parasites, usually lacking a sterile worker caste, which are dependent on their hosts for survival and reproduction. Social parasites are rare among the fungus‐gardening ants (Myrmicinae: tribe Attini) and only four species are known until now, all being inquilines from the Higher Attini. We describe Mycocepurus castrator sp.n. , the first inquiline social parasite to be discovered in the Lower Attini. Our study of the parasite's behaviour and life history supports the conclusion drawn from external morphology: Mycocepurus castrator is an evolutionarily derived inquiline parasite of Mycocepurus goeldii. Inquilines are of great interest to evolutionary biology because it is debated if they originated via sympatric or allopatric speciation. We discuss the life history evolution, behaviour and morphology of socially parasitic, fungus‐growing ants. 相似文献
74.
Tumang JR Negm RS Solt LA Schneider TJ Colarusso TP Hastings WD Woodland RT Rothstein TL 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(6):2712-2719
B cell susceptibility to Fas-mediated apoptosis is regulated in a receptor-specific fashion. CD40 engagement produces marked sensitivity to Fas killing, whereas surface Ig (sIg) engagement blocks Fas signaling for cell death in otherwise sensitive, CD40-stimulated B cell targets, and thus, induces a state of Fas resistance. The signaling mediator, Bruton's tyrosine kinase (Btk), is required for certain sIg-triggered responses, and Btk is reported to directly bind Fas and block Fas-mediated apoptosis. For these reasons, the role of Btk as a mediator of sIg-induced Fas resistance was examined. Dysfunction of Btk through mutation, and absence of Btk through deletion did not interfere with induction of Fas resistance by anti-Ig. This may be due, at least in part, to induction of Btk-dependent Bcl-2 family members by anti-Ig after CD40 ligand treatment. However, the susceptibility to Fas-mediated apoptosis of B cell targets stimulated by CD40 ligand alone was increased in the absence of Btk. These results indicate that Fas resistance produced by sIg triggering does not require Btk, but suggests that in certain situations Btk modulates B cell susceptibility to Fas killing. 相似文献
75.
76.
JERRY W. HUPP JOHN I. HODGES JR. BRUCE P. CONANT BRANDT W. MEIXELL DEBBIE J. GROVES 《The Journal of wildlife management》2010,74(2):274-284
ABSTRACT Management of Pacific Flyway Canada geese (Branta canadensis) requires information on winter distribution of different populations. Recoveries of tarsus bands from Vancouver Canada geese (B. canadensis fulva) marked in southeast Alaska, USA, ≥4 decades ago suggested that ≥83% of the population was non-migratory and that annual adult survival was high (Ŝ = 0.836). However, recovery distribution of tarsus bands was potentially biased due to geographic differences in harvest intensity in the Pacific Flyway. Also, winter distribution of Vancouver Canada geese could have shifted since the 1960s, as has occurred for some other populations of Canada geese. Because winter distribution and annual survival of this population had not recently been evaluated, we surgically implanted very high frequency radiotransmitters in 166 adult female Canada geese in southeast Alaska. We captured Vancouver Canada geese during molt at 2 sites where adults with goslings were present (breeding areas) and 2 sites where we observed nonbreeding birds only. During winter radiotracking flights in southeast Alaska, we detected 98% of 85 females marked at breeding areas and 83% of 70 females marked at nonbreeding sites, excluding 11 females that died prior to the onset of winter radiotracking. We detected no radiomarked females in coastal British Columbia, or western Washington and Oregon, USA. Most (70%) females moved ≤30 km between November and March. Our model-averaged estimate of annual survival (Ŝ = 0.844, SE = 0.050) was similar to the estimate of annual survival of geese marked from 1956 to 1960. Likely <2% of Vancouver Canada geese that nest in southeast Alaska migrate to winter areas in Oregon or Washington where they could intermix with Canada geese from other populations in the Pacific Flyway. Because annual survival of adult Vancouver Canada geese was high and showed evidence of long-term consistency, managers should examine how reproductive success and recruitment may affect the population. 相似文献
77.
MELODY J. BERNOT DANIEL J. SOBOTA ROBERT O. HALL JR PATRICK J. MULHOLLAND WALTER K. DODDS JACKSON R. WEBSTER JENNIFER L. TANK LINDA R. ASHKENAS LEE W. COOPER CLIFFORD N. DAHM STANLEY V. GREGORY NANCY B. GRIMM STEPHEN K. HAMILTON SHERRI L. JOHNSON WILLIAM H. MCDOWELL JUDITH L. MEYER BRUCE PETERSON GEOFFREY C. POOLE H. MAURICE VALETT CLAY ARANGO JAKE J. BEAULIEU AMY J. BURGIN CHELSEA CRENSHAW ASHLEY M. HELTON LAURA JOHNSON JEFF MERRIAM B. R. NIEDERLEHNER JONATHAN M. O’BRIEN JODY D. POTTER RICHARD W. SHEIBLEY SUZANNE M. THOMAS KYM WILSON 《Freshwater Biology》2010,55(9):1874-1890
1. Rates of whole‐system metabolism (production and respiration) are fundamental indicators of ecosystem structure and function. Although first‐order, proximal controls are well understood, assessments of the interactions between proximal controls and distal controls, such as land use and geographic region, are lacking. Thus, the influence of land use on stream metabolism across geographic regions is unknown. Further, there is limited understanding of how land use may alter variability in ecosystem metabolism across regions. 2. Stream metabolism was measured in nine streams in each of eight regions (n = 72) across the United States and Puerto Rico. In each region, three streams were selected from a range of three land uses: agriculturally influenced, urban‐influenced, and reference streams. Stream metabolism was estimated from diel changes in dissolved oxygen concentrations in each stream reach with correction for reaeration and groundwater input. 3. Gross primary production (GPP) was highest in regions with little riparian vegetation (sagebrush steppe in Wyoming, desert shrub in Arizona/New Mexico) and lowest in forested regions (North Carolina, Oregon). In contrast, ecosystem respiration (ER) varied both within and among regions. Reference streams had significantly lower rates of GPP than urban or agriculturally influenced streams. 4. GPP was positively correlated with photosynthetically active radiation and autotrophic biomass. Multiple regression models compared using Akaike’s information criterion (AIC) indicated GPP increased with water column ammonium and the fraction of the catchment in urban and reference land‐use categories. Multiple regression models also identified velocity, temperature, nitrate, ammonium, dissolved organic carbon, GPP, coarse benthic organic matter, fine benthic organic matter and the fraction of all land‐use categories in the catchment as regulators of ER. 5. Structural equation modelling indicated significant distal as well as proximal control pathways including a direct effect of land‐use on GPP as well as SRP, DIN, and PAR effects on GPP; GPP effects on autotrophic biomass, organic matter, and ER; and organic matter effects on ER. 6. Overall, consideration of the data separated by land‐use categories showed reduced inter‐regional variability in rates of metabolism, indicating that the influence of agricultural and urban land use can obscure regional differences in stream metabolism. 相似文献
78.
van Beers JJ Raijmakers R Alexander LE Stammen-Vogelzangs J Lokate AM Heck AJ Schasfoort RB Pruijn GJ 《Arthritis research & therapy》2010,12(6):R219
Introduction
Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology. 相似文献79.
80.
Research into dolphin swimming historically was guided by false assumptions pertaining to maximum speed. Accurate measurements on swimming speed and duration of effort of free-ranging dolphins are rare. To examine the variance of maximum swimming speeds, nearly 2,000 speed measurements were obtained for both captive and free-ranging dolphins, including Tursiops truncatus, Pseudorca crassidens, Delphinus capensis , and Delphinus delpbis . Measurements were made from videotapes of dolphins trained to swim fast around a large pool or jumping to a maximum height, videotapes of captured wild dolphins immediately after release, and sequential aerial photographs of a school of free-ranging dolphins startled by a passing airplane. Maximum horizontal speeds for trained animals were 8.2 m/sec for T. truncatus , 8.0 m/sec for D. delphis , and 8.0 m/sec for P. crassidens . Maximum speeds for T. truncatus swimming upwards, prior to vertical leaps ranged from 8.2 to 11.2 m/sec. Wild T. truncatus demonstrated a maximum speed of 5.7 m/sec. Maximum swimming speed of free-ranging D. capensis responding to multiple passes by a low flying airplane was 6.7 m/sec. There was no evidence that the freeranging dolphins have superior swimming capabilities to captive animals. The results of this study imply that realistic maximum swimming speeds for dolphins are lower than previous reports which were based on sparse data and imprecise measurement techniques. 相似文献