GENETICS OF GROWTH RATE IN OYSTERS AND ITS IMPLICATIONS FOR AQUACULTURE

1981 ◽  
Vol 23 (1) ◽  
pp. 119-130 ◽  
Author(s):  
Shiva M. Singh ◽  
E. Zouros
Keyword(s):  
Growth Rate ◽  
Crassostrea Virginica ◽  
Genetic Improvement ◽  
Large Scale ◽  
Genetic Manipulation ◽  
Limiting Factor ◽  
Oyster Aquaculture ◽  
Two Samples ◽  
One Year ◽  
Two Populations

Two samples of one-year-old American oysters (Crassostrea virginica Gmelin) obtained from the same inlet two years apart and grown under identical conditions were analyzed for their weight distribution and electrophoretic profiles at several enzyme loci. Although growth in the two years was significantly different, the electrophoretic profiles of the two populations were remarkably similar. On both occasions heterozygosity was positively correlated with mean weight and negatively correlated with the coefficient of variation. In general there was a deficiency of heterozygotes. This deficiency was more pronounced in the slow-growers than in the fast-growers. These observations suggest that growth rate (a limiting factor in current oyster aquaculture) can be improved by genetic manipulation. Use of large scale electrophoretic survey in providing guidelines for genetic improvement are discussed.

Comparison of growth and reproduction performance of dairy (Holstein-Friesian) and beef (Belgian Blue) replacement heifers in farms with both types of cattle

2001 ◽  
Vol 26 (2) ◽  
pp. 503-506
Author(s):  
V. de Behr ◽  
O. Gérard ◽  
J.L. Hornick ◽  
I. Dufrasne ◽  
L. Istasse
Keyword(s):  
Growth Rate ◽  
Live Weight ◽  
Dairy Herd ◽  
Limiting Factor ◽  
Holstein Friesian ◽  
Commercial Farms ◽  
Beef Herd ◽  
The Difference ◽  
One Year ◽  
Growth And Reproduction

AbstractIn Belgium, both dairy and beef cattle are managed intensively. Three commercial farms owning both a Belgian Blue —double muscled type- suckler beef herd and a Holstein-Friesian dairy herd were surveyed between 1994 and 1998. The aim of the study was to compare growth and reproduction performances of both breeds in a similar farm environment. The replacement heifers of both breeds were kept together until advanced pregnancy. Reproduction data were collected monthly from heifers older than fourteen months. The live weight of the replacement heifers was recorded quarterly until 20 months of age. Breed influenced the growth of replacement heifers at 6, 9 and 12 months (P < 0.001). The growth rate of Belgian Blue heifers was reduced after the age of one year and the live weight difference between breeds was not significant anymore. Belgian Blue heifers were always heavier than Holstein-Friesian heifers. Successfully bred heifers had a greater growth rate than non successfully bred heifers within the Belgian Blue breed. This was significant for the weight at 6 months (P < 0.05) and at 12 months (P < 0.05). Such an effect was not detected for the Holstein-Friesian breed (P > 0.05). Weight was not a limiting factor for fecundity of the Holstein-Friesian heifers. Management policies other than growth performance explained the difference between optimal fecundity and the fecundity index met in this study. Non successfully bred Belgian Blue heifers were lighter than successfully bred animals. Unsufficient weight performance had an impact on fecundity in that breed.

scholarly journals Mitotic instability in triploid and tetraploid one-year-old eastern oyster, Crassostrea virginica, assessed by cytogenetic and flow cytometry techniques

Genome ◽  
2018 ◽  
Vol 61 (2) ◽  
pp. 79-89 ◽  
Author(s):  
Joana Teixeira de Sousa ◽  
Standish K. Allen ◽  
Brittany M. Wolfe ◽  
Jessica Moss Small
Keyword(s):  
Flow Cytometry ◽  
Crassostrea Virginica ◽  
Chromosome Instability ◽  
Eastern Oyster ◽  
Chromosome Loss ◽  
Brood Stock ◽  
Oyster Aquaculture ◽  
Mitotic Instability ◽  
Significant Difference ◽  
One Year

For commercial oyster aquaculture, triploidy has significant advantages. To produce triploids, the principal technology uses diploid × tetraploid crosses. The development of tetraploid brood stock for this purpose has been successful, but as more is understood about tetraploids, it seems clear that chromosome instability is a principal feature in oysters. This paper is a continuation of work to investigate chromosome instability in polyploid Crassostrea virginica. We established families between tetraploids—apparently stable (non-mosaic) and unstable (mosaic)—and normal reference diploids, creating triploid groups, as well as tetraploids between mosaic and non-mosaic tetraploids. Chromosome loss was about the same for triploid juveniles produced from either mosaic or non-mosaic tetraploids or from either male or female tetraploids. However, there was a statistically significant difference in chromosome loss in tetraploid juveniles produced from mosaic versus non-mosaic parents, with mosaics producing more unstable progeny. These results confirm that chromosome instability, as manifested in mosaic tetraploids, is of little concern for producing triploids, but it is clearly problematic for tetraploid breeding. Concordance between the results from cytogenetics and flow cytometry was also tested for the first time in oysters, by assessing the ploidy of individuals using both techniques. Results between the two were non-concordant.

Changing Composition and Growth Performance of Services Sector in India after Liberalization

2020 ◽  
pp. 432-436
Keyword(s):  
Growth Rate ◽  
Growth Performance ◽  
Direct Investment ◽  
Service Sector ◽  
World Market ◽  
Limiting Factor ◽  
Arunachal Pradesh ◽  
Services Sector ◽  
State Economy ◽  
The World

This present study makes an analysis of changing contribution of sub-sector and composition and growth performance in Indian economy. In addition to that, the contribution of sub-sector of service sector in state economy. The results revealed that the growth rate of Chandigarh was high due to providing especial emphasis on dominating sub-sectors of services and its most preferred destination for technology whereas, Sikkim and Arunachal Pradesh due to geographical and environmental conditions development were higher in floriculture and agriculture, although, tourism emerged as a new profession and have different opportunities. Apart of that, in the wake of some challenges in the form of lack of infrastructure, recent crisis in the world market, foreign direct investment (FDI) restrictions and outsourcing backlash were major limiting factor.

scholarly journals Insectivorous songbirds as early indicators of future defoliation by spruce budworm

2021 ◽  
Author(s):  
Marion Germain ◽  
Daniel Kneeshaw ◽  
Louis De Grandpré ◽  
Mélanie Desrochers ◽  
Patrick M. A. James ◽  
...  
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Spruce Budworm ◽  
Detection Methods ◽  
Maximum Probability ◽  
Point Count ◽  
Probability Of Presence ◽  
Time Lagged ◽  
One Year ◽  
Local Sampling

Abstract Context Although the spatiotemporal dynamics of spruce budworm outbreaks have been intensively studied, forecasting outbreaks remains challenging. During outbreaks, budworm-linked warblers (Tennessee, Cape May, and bay-breasted warbler) show a strong positive response to increases in spruce budworm, but little is known about the relative timing of these responses. Objectives We hypothesized that these warblers could be used as sentinels of future defoliation of budworm host trees. We examined the timing and magnitude of the relationships between defoliation by spruce budworm and changes in the probability of presence of warblers to determine whether they responded to budworm infestation before local defoliation being observed by standard detection methods. Methods We modelled this relationship using large-scale point count surveys of songbirds and maps of cumulative time-lagged defoliation over multiple spatial scales (2–30 km radius around sampling points) in Quebec, Canada. Results All three warbler species responded positively to defoliation at each spatial scale considered, but the timing of their response differed. Maximum probability of presence of Tennessee and Cape May warbler coincided with observations of local defoliation, or provided a one year warning, making them of little use to guide early interventions. In contrast, the probability of presence of bay-breasted warbler consistently increased 3–4 years before defoliation was detectable. Conclusions Early detection is a critical step in the management of spruce budworm outbreaks and rapid increases in the probability of presence of bay-breasted warbler could be used to identify future epicenters and target ground-based local sampling of spruce budworm.

CONTINUOUS CULTURE OF BRUCELLA ABORTUS S.19

1961 ◽  
Vol 7 (4) ◽  
pp. 491-505 ◽  
Author(s):  
Andreas H. W. Hauschild ◽  
Hilliard Pivnick
Keyword(s):  
Growth Rate ◽  
Continuous Culture ◽  
Dilution Rate ◽  
Brucella Abortus ◽  
Specific Growth ◽  
Limiting Factor ◽  
Continuous Growth ◽  
Viable Cells ◽  
Metabolic Products ◽  
Growth Of Bacteria

An apparatus is described for the continuous growth of bacteria. Brucella abortus S.19 has been grown in continuous culture for periods up to 3 weeks with populations up to 2 × 1011viable cells per ml and without the establishment of nonsmooth variants.Concentrations between 3 × 109and 2 × 1011cells per ml could be maintained as a function of the dilution rate without the requirement of a known limiting factor in the medium. In a series of steady-state conditions, the specific growth rate increased steadily up to 0.28 hour−1with decreasing population levels.Incidence of mutants was governed by the dilution rate and could also be reduced by various chelating substances.In continuous growth combined with continuous dialysis, population levels were approximately twice those obtained in continuous growth without dialysis. The effect of dialysis appears to be the continuous removal of growth-limiting metabolic products.

Current State of (Dis)Integration: Public Health and Fusion Centers

2020 ◽  
Vol 17 (2) ◽  
Author(s):  
Cody Minks ◽  
Anke Richter
Keyword(s):  
Public Health ◽  
Law Enforcement ◽  
Information Sharing ◽  
Homeland Security ◽  
Large Scale ◽  
Ad Hoc ◽  
Limiting Factor ◽  
Fusion Centers ◽  
Public Health Emergencies ◽  
Public Health Information

AbstractObjectiveResponding to large-scale public health emergencies relies heavily on planning and collaboration between law enforcement and public health officials. This study examines the current level of information sharing and integration between these domains by measuring the inclusion of public health in the law enforcement functions of fusion centers.MethodsSurvey of all fusion centers, with a 29.9% response rate.ResultsOnly one of the 23 responding fusion centers had true public health inclusion, a decrease from research conducted in 2007. Information sharing is primarily limited to information flowing out of the fusion center, with little public health information coming in. Most of the collaboration is done on a personal, informal, ad-hoc basis. There remains a large misunderstanding of roles, capabilities, and regulations by all parties (fusion centers and public health). The majority of the parties appear to be willing to work together, but there but there is no forward momentum to make these desires a reality. Funding and staffing issues seem to be the limiting factor for integration.ConclusionThese problems need to be urgently addressed to increase public health preparedness and enable a decisive and beneficial response to public health emergencies involving a homeland security response.

scholarly journals The Revitalization of the Historic Centre of the Town Slany

2014 ◽  
Vol 12 ◽  
pp. 3-11
Author(s):  
Zuzana Pešková
Keyword(s):  
Regional Policy ◽  
Large Scale ◽  
Test Theory ◽  
Team Members ◽  
Practical Design ◽  
Historic Centre ◽  
Reconstruction Project ◽  
One Year ◽  
The Town ◽  
Large Scale Project

In 2006, the town council of Slany decided to respond to the new trend of regional policy in the Central Bohemia region and focused on the revitalization of the historic core of the town. The large-scale project was assigned to a team of professionals (teachers and graduates of the Faculty of Civil Engineering of the Czech Technical University in Prague), led by Professor Sykora. Team members are to deal with issues of historical centre. The project presented a challenge to test theory, principles and procedures in practical design. The projected area featured Masaryk Square and 22 adjacent streets defined by the existing town walls. The reconstruction project of Vinarickeho Street was the first part of the overall project of revitalization of the historic core of the town chosen to implement. This reconstruction was one of the most technically, organizationally and financially complex works that have been undertaken in Slany recently. Construction started in November 2010 and lasted one year. Although this is a project of smaller scope, thanks to its complexity, sensitive approach and craftsmanship it brought the creators the price Construction of the Year 2012 in the Central Bohemia region and advanced to the second round in the competition Construction of the Year 2012 in Czech Republic.

scholarly journals Flipping the Script: Measuring Both Performance Validity and Cognitive Ability with the Forced Choice Recognition Trial of the RCFT

2021 ◽  
pp. 003151252110197
Author(s):  
Kaitlyn Abeare ◽  
Kristoffer Romero ◽  
Laura Cutler ◽  
Christina D. Sirianni ◽  
Laszlo A. Erdodi
Keyword(s):  
Cognitive Ability ◽  
Verbal Memory ◽  
Visual Memory ◽  
Large Scale ◽  
Clinical Sample ◽  
Neuropsychological Test ◽  
Forced Choice ◽  
Control Group ◽  
Performance Validity ◽  
Two Samples

In this study we attempted to replicate the classification accuracy of the newly introduced Forced Choice Recognition trial (FCR) of the Rey Complex Figure Test (RCFT) in a clinical sample. We administered the RCFT FCR and the earlier Yes/No Recognition trial from the RCFT to 52 clinically referred patients as part of a comprehensive neuropsychological test battery and incentivized a separate control group of 83 university students to perform well on these measures. We then computed the classification accuracies of both measures against criterion performance validity tests (PVTs) and compared results between the two samples. At previously published validity cutoffs (≤16 & ≤17), the RCFT FCR remained specific (.84–1.00) to psychometrically defined non-credible responding. Simultaneously, the RCFT FCR was more sensitive to examinees’ natural variability in visual-perceptual and verbal memory skills than the Yes/No Recognition trial. Even after being reduced to a seven-point scale (18-24) by the validity cutoffs, both RCFT recognition scores continued to provide clinically useful information on visual memory. This is the first study to validate the RCFT FCR as a PVT in a clinical sample. Our data also support its use for measuring cognitive ability. Replication studies with more diverse samples and different criterion measures are still needed before large-scale clinical application of this scale.

scholarly journals Condom Use During Last Sexual Contact and Last 30 Days in Two Samples of Caribbean Military Personnel

2011 ◽  
Vol 6 (2) ◽  
pp. 132-135 ◽  
Author(s):  
Rachel Hallum-Montes ◽  
Rohan D’Souza ◽  
Maria Isabel Tavarez ◽  
Russell Manzanero ◽  
Grace E. Dann ◽  
...  
Keyword(s):  
Condom Use ◽  
Large Scale ◽  
Monitoring And Evaluation ◽  
Armed Forces ◽  
Sexual Contact ◽  
Unprotected Sex ◽  
Sexually Transmitted ◽  
Populations At Risk ◽  
Two Samples ◽  
Biological And Behavioral Surveillance

Condom use during last sexual contact is a survey measure that may be used to inform monitoring and evaluation indicators of recent condom use in populations at risk for HIV infection and other sexually transmitted infections, such as the uniformed services. The authors tested for differences in condom use measures that were fielded within separate Biological and Behavioral Surveillance Surveys conducted in the armed forces of two separate nations: the Dominican Republic and Belize. Both surveys included measures of condom use during last sexual contact with specified partners and both surveys included the Risk Behavior Assessment (RBA), which measures specific sexual acts and condom use frequency during a specified time period. In both samples, more than 40% of respondents who reported condom use during last sexual contact with a regular partner also reported engaging in unprotected sex when screened with the RBA. Furthermore, more than 60% of respondents who reported condom use during last sexual encounter with a commercial sex worker also reported engaging in unprotected sex when screened with the RBA. The results carry implications for monitoring and evaluation indicators of large-scale HIV prevention programs. The authors recommend that, when feasible, more in-depth instruments such as the RBA be considered to measure recent condom use in populations of uniformed services personnel.

Towards A Multi-FPGA Infrared Simulator

2007 ◽  
Vol 4 (4) ◽  
pp. 343-355 ◽  
Author(s):  
Vinay Sriram ◽  
David Kearney
Keyword(s):  
Homeland Security ◽  
Reconfigurable Computing ◽  
High Speed ◽  
High Performance ◽  
Large Scale ◽  
Computation Time ◽  
Ccd Camera ◽  
Hardware Acceleration ◽  
Limiting Factor ◽  
Scene Simulation

High speed infrared (IR) scene simulation is used extensively in defense and homeland security to test sensitivity of IR cameras and accuracy of IR threat detection and tracking algorithms used commonly in IR missile approach warning systems (MAWS). A typical MAWS requires an input scene rate of over 100 scenes/second. Infrared scene simulations typically take 32 minutes to simulate a single IR scene that accounts for effects of atmospheric turbulence, refraction, optical blurring and charge-coupled device (CCD) camera electronic noise on a Pentium 4 (2.8GHz) dual core processor [7]. Thus, in IR scene simulation, the processing power of modern computers is a limiting factor. In this paper we report our research to accelerate IR scene simulation using high performance reconfigurable computing. We constructed a multi Field Programmable Gate Array (FPGA) hardware acceleration platform and accelerated a key computationally intensive IR algorithm over the hardware acceleration platform. We were successful in reducing the computation time of IR scene simulation by over 36%. This research acts as a unique case study for accelerating large scale defense simulations using a high performance multi-FPGA reconfigurable computer.

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