Date

Distribution by Scientific Domains
Distribution within Life Sciences

Kinds of Date

  • announcement date
  • arrival date
  • birth date
  • breeding date
  • calving date
  • census date
  • collection date
  • different date
  • divergence date
  • early date
  • emergence date
  • event date
  • expiration date
  • harvest date
  • hatch date
  • hatching date
  • heading date
  • index date
  • initiation date
  • laying date
  • planting date
  • publication date
  • quit date
  • radiocarbon date
  • same date
  • sampling date
  • several date
  • sowing date
  • start date
  • treatment date

  • Terms modified by Date

  • date palm

  • Selected Abstracts


    Les tombes juives en Europe : commémoration publique ou espace rituel ?

    MUSEUM INTERNATIONAL EDITION FRANCAISE, Issue 1-2 2010
    Max Polonovski
    Résumé Le cas du cimetière de Nis, en ex-Yougoslavie, pourrait constituer un bon exemple de la complexité de la situation des cimetières juifs en Europe de l'est. Il s'agit d'un cimetière sépharade de plus de 1 000 tombes, qui comporte de nombreuses pierres tombales aux inscriptions cabalistiques très intéressantes et très rares. L'anéantissement total de la communauté juive pendant l'occupation nazie et la confiscation du cimetière par le gouvernement communiste ont entraîné un processus d'abandon (Note à l'éditeur : INSÉRER LA DATE). Une communauté de Roms s'est emparée du lieu et s'y est installée, logée dans l'oratoire et les tombes. À la fin des années 1990, un responsable de la communauté juive de Bosnie se mit à protester contre cette profanation. Des intellectuels juifs joignirent leurs voix à la sienne pour obtenir du gouvernement le déménagement de la colonie tzigane. Il fallut plusieurs années de campagne internationale et le travail d'un groupe de volontaires pour nettoyer le cimetière et engager sa restauration. L'impression de vandalisme scandaleux est amplifiée par la présence des tziganes. Une minorité persécutée occupe de manière choquante l'espace sacré d'une autre minorité persécutée. [source]


    THE DATE AND SEQUENCE OF USE OF NEOLITHIC FUNERARY MONUMENTS: NEW AMS DATING EVIDENCE FROM THE COTSWOLD-SEVERN REGION

    OXFORD JOURNAL OF ARCHAEOLOGY, Issue 4 2006
    MARTIN SMITH
    Summary. In this paper we discuss 26 new Neolithic AMS dates obtained from human and animal bone from four previously undated funerary monuments in the Cotswold-Severn region. By strategically targeting particular portions of these skeletal assemblages, a number of valuable inferences are made concerning the extent of variation in apparently co-existing burial practices both within and between monuments. Of particular interest is the observation that variations in the extent to which interments have become disarticulated cannot necessarily be equated with chronological relationships regarding their deposition. This project has also obtained dates from cremated bone, which establish that the range of funerary treatments in practice during the earlier Neolithic also included cremation. Additionally it is observed that whilst some, apparently primary, deposits may in fact be later insertions, other material in apparently secondary contexts may actually return earlier Neolithic dates. [source]


    DATE OF THE MOAT OF ABOMEY

    ACTA ARCHAEOLOGICA, Issue 1 2009
    Article first published online: 5 JUL 2010
    No abstract is available for this article. [source]


    ON THE ROAD TO PARADIS: NEW INSIGHTS FROM AMS DATES AND STABLE ISOTOPES AT LE DÉHUS, GUERNSEY, AND THE CHANNEL ISLANDS MIDDLE NEOLITHIC

    OXFORD JOURNAL OF ARCHAEOLOGY, Issue 2 2010
    RICK J. SCHULTING
    Summary We here report the results of a programme of AMS dating and stable isotope analysis on human remains from the chambered tomb of Le Déhus, Guernsey. An early use-phase in the range 4100,3900 BC is indicated, confirming the monument's attribution to the Middle Neolithic II as defined in western France. Late Neolithic burial activity is also identified. Stable carbon isotope measurements provide little or no evidence for the consumption of marine foods, although stable nitrogen isotope values are unusually high. These results are situated in the wider context of Neolithic mortuary monuments of the Channel Islands and Normandy. [source]


    RADIOCARBON DATES FROM THE OXFORD AMS SYSTEM: ARCHAEOMETRY DATELIST 33

    ARCHAEOMETRY, Issue 2 2009
    C. BRONK RAMSEY
    First page of article [source]


    RADIOCARBON DATES FROM THE OXFORD AMS SYSTEM: ARCHAEOMETRY DATELIST 32

    ARCHAEOMETRY, Issue 2007
    T. F. G. HIGHAM
    First page of article [source]


    The Defensive Expansion Approach to Multinational Banking: Evidence to Date

    FINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 2 2002
    Barry Williams
    First page of article [source]


    Effect of Planting Date on Seed Yield, Oil Content and Fatty Acid Composition of Safflower (Carthamus tinctorius) Cultivars Grown in the Mediterranean Region of Turkey

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2003
    B. Samanc
    Abstract A study was conducted to investigate the effect of different planting dates (25 April, 5 May and 15 May 1998 and 30 April, 15 May and 25 May 1999) on the seed yield, oil content and fatty acid composition of three safflower (Carthamus tinctorius) cultivars (Yenice 5-38, Dincer 5-118 and 5-154) grown in fields of the research facility of Akdeniz University in Antalya, Turkey. While seed yield, oil content, and palmitic acid, stearic acid, and oleic acid contents decreased, linoleic acid content increased from 50.86 to 55.72 % with delay in planting date. The effect of genotype on fatty acids was greater than that of environment. [source]


    B-Type Natriuretic Peptide Is Associated with Mortality in Older Functionally Impaired Patients

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2005
    Miles D. Witham BM
    Objectives: To determine the predictive power of B-type natriuretic peptide (BNP) regarding death in older, functionally impaired patients with multiple comorbidity. Design: Prospective cohort study. Setting: Specialist geriatric assessment clinic and day hospital. Participants: Two hundred ninety-nine older, functionally impaired patients, mean age 79 at enrollment. Measurements: Full clinical history and examination, baseline BNP, and echocardiography. Date and cause of death were ascertained from Scottish death records. Kaplan-Meier survival curves were constructed for quartiles of log (BNP), and the contribution of BNP to prediction of death was investigated. Results: The follow-up period ranged from 3.9 to 5.2 years (mean 4.4 years). BNP was a powerful independent predictor of all-cause and cardiovascular mortality. BNP was a more powerful predictor than blood pressure, diabetes mellitus, smoking, echocardiographic left ventricular hypertrophy, left ventricular systolic dysfunction, or age. BNP predicted death in those with and without a previous cardiovascular event at baseline. Conclusion: BNP has significant predictive power for death in older, functionally impaired patients. [source]


    CÔTE D'IVOIRE: Election Date At Last

    AFRICA RESEARCH BULLETIN: POLITICAL, SOCIAL AND CULTURAL SERIES, Issue 8 2010
    Article first published online: 20 SEP 2010
    No abstract is available for this article. [source]


    GUINEA: New Date Fixed

    AFRICA RESEARCH BULLETIN: POLITICAL, SOCIAL AND CULTURAL SERIES, Issue 8 2010
    Article first published online: 20 SEP 2010
    No abstract is available for this article. [source]


    Genetic Diversity and Association Analysis for Salinity Tolerance, Heading Date and Plant Height of Barley Germplasm Using Simple Sequence Repeat Markers

    JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 8 2008
    Lilia Eleuch
    Abstract The objective of this study was to investigate the genetic diversity of barley accessions. Additionally, association trait analysis was conducted for grain yield under salinity, heading date and plant height. For this purpose, 48 barley genotypes were analyzed with 22 microsatellite simple sequence repeat (SSR) markers. Four of the 22 markers (Bmac316, scssr03907, HVM67 and Bmag770) were able to differentiate all barley genotypes. Cluster and principal coordinate analysis allowed a clear grouping between countries from the same region. The genotypes used in this study have been evaluated for agronomic performance in different environments. Conducting association analysis for grain yield under salinity conditions using TASSEL software revealed a close association of the marker Bmag749 (2H, bin 13) in two different environments with common significant alleles (175, 177), whereas the HVHOTR1 marker (2H, bin 3) was only significant in Sakhar_Egypt with alleles size being 158 and 161. Heading date also showed an association with scssr03907 through the common significant specific allele 111 and EBmac0415 markers in three different agro climatic locations, whereas HVCMA, scssr00103 and HVM67 were linked to heading date in the Egyptian environment only. The plant height association analysis revealed significant markers Bmag770 via the significant allele 152 and scssr09398. [source]


    Genotyping the Heading Date of Male-Sterile Rice Line II-32A

    JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2006
    Jun-Feng Xu
    Abstract II-32A, an elite male-sterile line of rice (Oryza sativa L.), has been widely used for the production of hybrid rice seed in China. Heading date in most combinations using II-32A shows transgressive inheritance or similarity to the latter parent, but the genotype of II-32A with respect to major genes for heading time is unknown. This limits the further exploitation of this sterile line in breeding and hybrid seed production. Using a number of major gene heading date isogenic lines and heading date QTL near-isogenic lines, we genetically analyzed II-32B under both long- and short-day conditions. We show that II-32B carries two photoperiod-sensitive genes, E1 and E3, a recessive late-heading gene, ef-1, and a photoperiod-sensitive allele, Se-1u. In addition we identified in II-32B a recessive inhibitor for E1 or Se-1n and other modified photoperiod-sensitive genes. The heading-date constitution of II-32A was determined to be E1e2E3Se-1uef-1i-Se-1. (Managing editor: Li-Hui Zhao) [source]


    Effects of date extract on adhesion of Candida species to human buccal epithelial cells in vitro

    JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 5 2000
    Khaled H. Abu-Elteen
    Abstract: The adherence of three Candida species to human buccal epithelial cells (BEC) following treatment with different concentrations of date extract was investigated in vitro, as well as the effect of a mouth rinse with date extract on the adhesion of yeast to BEC. Adhesion of C.albicans, C.tropicalis and C.kefyr to BEC was significantly reduced after both short- and long-term periods of yeast exposure to various concentrations of date extract (reduction between 25% and 52% of the control value). A similar inhibition of adherence was observed upon pre-incubation of BEC with date extract. There was a significant reduction (P<0.001) in the adherence of yeast to BEC collected immediately or 5,20 min after an oral rinse with 10% date extract. No statistically significant difference was observed in the adhesion of BEC collected 30 min after an oral rinse with date extract and control BEC. In addition, pre-treatment of either Candida or BEC, or both, with date extract resulted in reduced adherence, the magnitude of which was largest when both types of cells were pre-treated. Date extract also inhibited germ-tube formation of C. albicans (56,85% inhibition), which might contribute to the effects on adherence. [source]


    Pacemaker Stored Electrograms: Teaching Us What Is Really Going On in Our Patients

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2002
    BERND NOWAK
    NOWAK, B.: Pacemaker Stored Electrograms: Teaching Us What Is Really Going On in Our Patients. Stored electrograms (EGMs), well-known diagnostic tools in implantable cardioverter defibrillators, have now been incorporated in pacemakers as well, thereby increasing their diagnostic capabilities. The clinician can detect and diagnose patient arrhythmias with EGMs and directly validate diagnostic data stored by the devices. The appropriateness of detection algorithms can also be judged. Initial experiences with pacemaker EGMs reveals their potential to detect and diagnose sensing or detection algorithm problems. These so-called "false-positive" EGMs help to optimize pacemaker programming. Date and time stamp can correlate an event to patient symptoms. Recent advances, like onset recordings and marker annotation, have further increased the effectiveness of stored EGMs. The use of patient-triggered magnet-stored EGMs facilitates diagnostic workups in symptomatic pacemaker patients and reveals nondevice related symptoms in a considerable number of cases. Stored EGMs in pacemakers will soon be a standard diagnostic tool that can illustrate what is really going on in our patients. [source]


    Warts, Malnutrition, and Sunshine

    PEDIATRIC DERMATOLOGY, Issue 3 2008
    ROCÍO OROZCO-TOPETE M.D.
    We sought to determine the prevalence of warts in children of two communities in Oaxaca, Mexico, and compared it with their nutritional status. Children from Santa Catarina Yahuio and Santiago Laxopa of the state of Oaxaca were examined. Localization, number, and type of verruca were noted. Date of birth, height, and weight were obtained to determine nutritional status. A total of 213 children (116 girls and 97 boys), 107 in Yahuio and 106 in Laxopa, were studied. Mean age was 10.24 years. Thirty children (14.1%) had warts and 80% (24/30) of these lived in Yahuio (p = 0.0002). Almost half were teenagers. Most lesions were on sun-exposed areas. First degree malnutrition was found in 24.5%; second degree in 23.6% and third degree in 14.2%. A higher frequency of warts than previously reported was found. Malnutrition was prevalent in both groups but did not correlate positively with verruca. Verruca were more frequent in females, adolescents, sun-exposed areas, and higher altitude. We believe that the higher altitude of Yahuio facilitates greater exposure to ultraviolet light-induced immune suppression. [source]


    Systemic Sclerosis Up To Date (Special Issue)

    THE JOURNAL OF DERMATOLOGY, Issue 1 2010
    Kazuhiko TAKEHARA M.D., Ph.D.
    No abstract is available for this article. [source]


    The Introduction of Choice of Superannuation Fund: Results to Date

    AUSTRALIAN ACCOUNTING REVIEW, Issue 40 2006
    ROSS CLARE
    Commonwealth legislation providing for choice of superannuation fund has now been in operation since 1 July 2005. This paper explores the extent to which employees have exercised choice in the period immediately following the implementation of fund choice. The data available suggest that choice of fund has had only a modest impact. However, while community awareness of superannuation has increased and the level of member attachment to the main superannuation fund has increased, a downturn in investment returns, and subsequently in member sentiment, could have a significant impact on member preparedness to choose another fund [source]


    Continuity of Caregivers for Care During Pregnancy and Childbirth

    BIRTH, Issue 3 2000
    E.D. Hodnett
    A substantive amendment to this systematic review was last made on 17 May 1999. Cochrane reviews are regularly checked and updated if necessary. ABSTRACT Background: Social support may include advice or information, tangible assistance, and emotional support. Objectives: The objective of this review was to assess the effects of continuous support during labour (provided by health care workers or lay people) on mothers and babies. Search strategy: I searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. Date of last search: April 1999. Selection criteria: Randomised trials comparing continuous support during labour with usual care. Data collection and analysis: Trial quality was assessed. Study authors were contacted for additional information. Main results: Fourteen trials, involving more than 5000 women, are included in the Review. The continuous presence of a support person reduced the likelihood of medication for pain relief, operative vaginal delivery, Caesarean delivery, and a 5-minute Apgar score less than 7. Continuous support was also associated with a slight reduction in the length of labour. Six trials evaluated the effects of support on mothers' views of their childbirth experiences; while the trials used different measures (overall satisfaction, failure to cope well during labour, finding labour to be worse than expected, and level of personal control during childbirth), in each trial the results favoured the group who had received continuous support. Reviewers' conclusions: Continuous support during labour from caregivers (nurses, midwives, or lay people) appears to have a number of benefits for mothers and their babies and there do not appear to be any harmful effects. Citation: Hodnett ED. Caregiver support for women during childbirth (Cochrane Review). In: The Cochrane Library, Issue 1, 2000. Oxford: Update Software. [source]


    Re-Dating the Moraines at Skálafellsjökull and Heinabergsjökull using different Lichenometric Methods: Implications for the Timing of the Icelandic Little Ice Age Maximum

    GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 4 2004
    Krista M. Mckinzey
    Abstract Little Ice Age (LIA) moraines along the margins of Skálafellsjökull and Heinabergsjökull, two neighbouring outlet glaciers flowing from the Vatnajökull ice-cap, have been re-dated to test the reliability of different lichenometric approaches. During 2003, 12 000 lichens were measured on 40 moraine fragments at Skálafellsjökull and Heinabergsjökull to provide surface age proxies. The results are revealing. Depending on the chosen method of analysis, Skálafellsjökull either reached its LIA maximum in the early 19th century (population gradient) or the late 19th century (average of five largest lichens), whereas the LIA maximum of Heinabergsjökull occurred by the mid-19th century (population gradient) or late-19th century (average of 5 largest lichens). Discrepancies (c. 80 years for Skálafellsjökull and c. 40 years for Heinabergsjökull) suggest that the previously cited AD 1887 LIA maxima for both glaciers should be reassessed. Dates predicted by the lichen population gradient method appear to be the most appropriate, as mounting evidence from other geochronological reconstructions and sea-ice records throughout Iceland tends to support an earlier LIA glacier maximum (late 18th to mid-19th century) and probably reflects changes in the North Atlantic Oscillation. These revised chronologies shed further light on the precise timing of the Icelandic LIA glacier maximum, whilst improving our understanding of glacier-climate interactions in the North Atlantic. [source]


    Nursing Conference Dates for 2007

    JOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 1 2007
    Article first published online: 17 JAN 200
    No abstract is available for this article. [source]


    Phylogenetic relationships, diversification and biogeography in Neotropical Brotogeris parakeets

    JOURNAL OF BIOGEOGRAPHY, Issue 9 2009
    Camila C. Ribas
    Abstract Aim, We present a molecular phylogenetic analysis of Brotogeris (Psittacidae) using several distinct and complementary approaches: we test the monophyly of the genus, delineate the basal taxa within it, uncover their phylogenetic relationships, and finally, based on these results, we perform temporal and spatial comparative analyses to help elucidate the historical biogeography of the Neotropical region. Location, Neotropical lowlands, including dry and humid forests. Methods, Phylogenetic relationships within Brotogeris were investigated using the complete sequences of the mitochondrial genes cyt b and ND2, and partial sequences of the nuclear intron 7 of the gene for Beta Fibrinogen for all eight species and 12 of the 17 taxa recognized within the genus (total of 63 individuals). In order to delinetae the basal taxa within the genus we used both molecular and plumage variation, the latter being based on the examination of 597 skin specimens. Dates of divergence and confidence intervals were estimated using penalized likelihood. Spatial and temporal comparative analyses were performed including several closely related parrot genera. Results,Brotogeris was found to be a monophyletic genus, sister to Myiopsitta. The phylogenetic analyses recovered eight well-supported clades representing the recognized biological species. Although some described subspecies are diagnosably distinct based on morphology, there was generally little intraspecific mtDNA variation. The Amazonian species had different phylogenetic affinities and did not group in a monophyletic clade. Brotogeris diversification took place during the last 6 Myr, the same time-frame as previously found for Pionus and Pyrilia. Main conclusions, The biogeographical history of Brotogeris implies a dynamic history for South American biomes since the Pliocene. It corroborates the idea that the geological evolution of Amazonia has been important in shaping its biodiversity, argues against the idea that the region has been environmentally stable during the Quaternary, and suggests dynamic interactions between wet and dry forest habitats in South America, with representatives of the Amazonian biota having several independent close relationships with taxa endemic to other biomes. [source]


    Biogeography and molecular phylogeny of the genus Schizothorax (Teleostei: Cyprinidae) in China inferred from cytochrome b sequences

    JOURNAL OF BIOGEOGRAPHY, Issue 8 2006
    Dekui He
    Abstract Aim, To test a vicariant speciation hypothesis derived from geological evidence of large-scale changes in drainage patterns in the late Miocene that affected the drainages in the south-eastern Tibetan Plateau. Location, The Tibetan Plateau and adjacent areas. Methods, The cytochrome b DNA sequences of 30 species of the genus Schizothorax from nine different river systems were analysed. These DNA sequences were analysed using parsimony, maximum likelihood and Bayesian methods. The approximately unbiased and Shimodaira,Hasegawa tests were applied to evaluate the statistical significance of the shortest trees relative to alternative hypotheses. Dates of divergences between lineages were estimated using the nonparametric rate smoothing method, and confidence intervals of dates were obtained by parametric bootstrapping. Results, The phylogenetic relationships recovered from molecular data were inconsistent with traditional taxonomy, but apparently reflected geographical associations with rivers. Within the genus Schizothorax, we observed a divergence between the lineages from the Irrawaddy,Lhuit and Tsangpo,Parlung rivers, and tentatively dated this vicariant event back to the late Miocene (7.3,6.8 Ma). We also observed approximately simultaneous geographical splits within drainages of the south-eastern Tibetan Plateau, the Irrawaddy, the Yangtze and the Mekong,Salween rivers in the late Miocene (7.1,6.2 Ma). Main conclusions, Our molecular evidence tentatively highlights the importance of palaeoriver connections and the uplift of the Tibetan Plateau in understanding the evolution of the genus Schizothorax. Molecular estimates of divergence times allowed us to date these vicariant scenarios back to the late Miocene, which agrees with geological suggestions for the separation of these drainages caused by tectonic uplift in south-eastern Tibet. Our results indicated the substantial role of vicariant-based speciation in shaping the current distribution pattern of the genus Schizothorax. [source]


    Factors predicting mortality in midlife adults with and without Down syndrome living with family

    JOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 12 2007
    A. J. Esbensen
    Abstract Background Little is known about the mortality of individuals with Down syndrome who have lived at home with their families throughout their lives. The current study evaluates the predictors, causes and patterns of mortality among co-residing individuals in midlife with Down syndrome as compared with co-residing individuals with ID owing to other causes. Method This paper examines mortality in 169 individuals with and 292 individuals without Down syndrome from 1988 to 2007. Dates and causes of death were obtained from maternal report, the Social Security Death Index and the National Death Index. Risk factors predicting mortality, including demographic variables, transition variables, and initial and change measures of health, functional abilities and behaviour problems, were obtained from maternal report. Results Having Down syndrome is a risk factor of mortality, net of other risk factors including older age, poorer functional abilities, worsening behaviour problems, residential relocation and parental death. The causes of death among individuals with and without Down syndrome who are in midlife and co-residing with their families are similar, and are most commonly due to cardiovascular or respiratory problems. Conclusions The findings indicate that midlife adults with Down syndrome who co-reside with their families generally exhibit similar causes of mortality as do midlife adults with intellectual disability owing to other causes, but show an elevated risk of mortality in midlife net of other variables, such as age and changes in functional abilities and behaviour problems. [source]


    Oyster Crassostrea virginica Spat Settlement as it Relates to the Restoration of Fish River Reef in Mobile Bay, Alabama

    JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2000
    Imad G. Saoud
    Spat collectors at the reefs were replaced every 2 wk and spat-set estimated as number of oysters per meter square per day. Water quality data at Fish River Reef was monitored using remote sensors. Spat-set data revealed significant variation between the four sites and between the 2 yr. Spat settlement was 5 to 10 times greater at the other three reefs than at Fish River Reef. Dates and intensity of oyster settlement at Fish River Reef were different from dates and intensity of oyster settlement at Shell Bank Reef, both on the eastern side of the bay. However, settlement was similar between Cedar Point Reef and White House Reef, both on the western side of the bay. Spat set appears to occur 3 wk after a rapid decline in water temperature, provided adequate oxygen concentrations are present at the time of settlement. Data collected suggest that intensity of settlement at Fish River Reef is considerably less than at other reefs in this study but could be adequate to reestablish the reef, if cultch and environmental conditions are suitable. The data also suggest that the source of larval oysters at Fish River Reef is different from the source of larval oysters at the other sites tested in the present study. [source]


    Save the dates,CPR's corporate leadership award dinner, and the 2010 Annual Meeting

    ALTERNATIVES TO THE HIGH COST OF LITIGATION, Issue 6 2009
    Russ Bleemer
    Dates for the 2009 CPR Institute Corporate Leadership Award Dinner, and next January's Annual Meeting, as well as training information and another look back at this year's Annual Meeting. [source]


    A long-term study of non-native-heartworm transmission among coyotes in a Mediterranean ecosystem

    OIKOS, Issue 3 2003
    Benjamin N. Sacks
    In Mediterranean ecosystems, abiotic factors are known to affect vertebrate population dynamics, but little is known about how these factors affect population dynamics of parasites. We conducted a 9-year investigation of the roles of temperature, precipitation, and vector abundance as determinants of transmission of the non-native canine heartworm (Dirofilaria immitis), a dangerous parasite of pets, among coyotes (Canis latrans), an important reservoir, in north-coastal California. Dates of heartworm transmission and total annual transmission were determined, respectively, from lengths and numbers of heartworms found in known-age coyotes. Vector host-seeking activity was assessed through weekly mosquito trapping. Within years, heartworm transmission occurred only when cumulative temperatures were sufficient to allow larval heartworms to develop to the infective stage (as predicted by an existing degree-day model), and when suitable vectors were available. Most (95%) heartworms infected their hosts between 1 July and 14 September. The onset of transmission periods always occurred after the peak in vector host-seeking activity and varied annually. Transmission periods ended before temperatures became limiting due to absence of vectors. The timing of host-seeking activity of the primary vector species, Ochlerotatus sierrensis, also was correlated with the onset of warming temperatures such that parasite and vector phenology were synchronized. For this reason (partly), the variation in timing of seasonal warming had no detectable effect on total annual transmission. Abundance of host-seeking Oc. sierrensis was positively correlated with annual precipitation, and annual heartworm transmission was positively correlated with abundance of host-seeking Oc. sierrensis. Annual transmission also was positively correlated with abundance of a less numerous vector species, Anopheles punctipennis, and was directly correlated with precipitation. This study demonstrates that multiannual variability in temperature, which affects seasonality of transmission, has little effect on annual transmission, but that precipitation is a driving force determining annual transmission. These findings imply that in California, and possibly other Mediterranean climate zones, it is especially important to preventively treat pets in summers following high-rainfall winters. [source]


    In vitro micro-tuber initiation and dormancy in yam

    ANNALS OF APPLIED BIOLOGY, Issue 2 2010
    E.I. Hamadina
    Dormancy is a mechanism that regulates the timing of sprouting (germination) of affected plant parts as well as ensures that the food quality of edible parts is maintained in storage until the following growing season. In yam, however, little is known about the control of tuber initiation or tuber dormancy. The objective of this study was to determine the effects of selected plant growth regulators (PGRs) on tuber initiation and dormancy, using an in vitro system. In two replicated experiments, 2-chloroethylphosphonic acid (ethephon, an ethylene source), abscisic acid (ABA) and gibberellin (GA3) , and their inhibitors silver nitrate, fluridone and 2-chloroethyl-trimethylammonium chloride, respectively , were added at two concentrations to the culture medium prior to explant culture. Dates of micro-tuber initiation and sprouting (end of dormancy) and tuber number were recorded. In the control (no PGR) in Experiment 1, micro-tubers were initiated at the base of the stem after 176 days and sprouted 235 days later, that is 411 days after culturing. Most PGR treatments had only small effects (±30 days) on the duration of dormancy and the time of micro-tuber initiation. However, in GA3 micro-tuber initiation occurred after 76 days, about 100 days earlier than in the control, whereas fluridone affected the position of micro-tubers and duration of dormancy. With fluridone treatments, tubers were found at the base of the stem (normal position) and on lower and upper nodes. Lower node tubers sprouted within 225 days of culturing compared with about 420 days after culturing at other nodal positions and in other PGR treatments. These data suggest an important role for ABA and gibberellic acid in yam micro-tuber initiation and the induction of dormancy. [source]


    An educational computer tool for simulating long-term soil erosion on agricultural landscapes

    COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 3 2009
    F. J. Jiménez-Hornero
    Abstract Due to its economic and environmental impacts, soil erosion has been a major concern to farmers, engineers and policy makers in recent years. Water and tilling are two of the main agents responsible for this phenomenon and considerable efforts have been made to model them in previous work but not with educational purposes. A computer tool for facilitating any user's simulation of long-term landscape evolution in a plot due to the combined action of water and tillage erosion is presented here. It integrates a graphic user interface with two well-verified erosion models, each one independently devoted to reproduce the effects of water and tilling. This computer tool permits to the student the consideration of the erosivity index and the presence of a crop in the plot, when simulating water erosion, as well as the planning of a different type of tilling each year. Each kind of tilling corresponds to a different combination of tillage tools with their own date, tillage depth and tillage direction. A handy ASCII (XYZ) file is generated containing the long-term soil erosion spatial pattern as result. From this information, the student can derive other results that will help to understand soil erosion. An example is presented here with the aim of showing how to use this computer tool to simulate this phenomenon on an agricultural landscape with a complex topography. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 253,262, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20193 [source]


    Finding stale-value errors in concurrent programs

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2004
    Michael Burrows
    Abstract Concurrent programs can suffer from many types of errors, not just the well-studied problems of deadlocks and simple race conditions on variables. This paper addresses a kind of race condition that arises from reading a variable whose value is possibly out of date. The paper introduces a simple technique for detecting such stale values, and reports on the encouraging experience with a compile-time checker that uses the technique. Copyright © 2004 John Wiley & Sons, Ltd. [source]