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Journal articles on the topic "Boar semen"

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Jovičić, Marija, Eva Chmelíková, and Markéta Sedmíková. "Cryopreservation of boar semen." Czech Journal of Animal Science 65, No. 4 (April 30, 2020): 115–23. http://dx.doi.org/10.17221/47/2020-cjas.

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Sperm cryopreservation is the best technology for long-term storage of the semen. However, the damage of boar spermatozoa by cryopreservation is more severe than in other animal species and a standardized freezing protocol for efficient cryopreservation has not been established yet. Semen quality and freezability vary greatly between breeds as well as between individual boars and even the season. Boar spermatozoa are sensitive to low temperatures; they sustain damage and a high rate of mortality and freezing/thawing the boar semen may strongly impair the sperm function and decrease the semen quality. The freezability of boar semen can be influenced by a cryopreservation procedure, and also by using various additives to freezing and thawing extenders such as antioxidants. In order to obtain acceptable results after thawing the boar semen, it is necessary to combine an optimal amount of additives (glycerol, egg yolk, sugars, antioxidants), cooling and warming velocities.
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Milovanović, Aleksandar, Tomislav Barna, Dubravka Milanov, and Miodrag Lazarević. "MODEL FOR COOPERATION BETWEEN BOAR STUDS AND LABORATORIES FOR REPRODUCTION IN BOARS’ SEMEN QUALITY CONTROL." Archives of Veterinary Medicine 6, no. 1 (September 6, 2013): 57–70. http://dx.doi.org/10.46784/e-avm.v6i1.145.

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In this article we presented procedures and results of boar semen quality control performed at the Scientific Veterinary Institute “Novi Sad” based on continuous cooperation with the farms’ centers for boar semen production. Th e data obtained by computer analysis (CASA-computer assisted sperm analysis), flow cytometry and cyto-morphologic examination were used for semen quality evaluation. Th e selected parameters were compared with the reproductive results in sows, such as: farrowing rate, number of piglets per litter, ratio of piglets born alive and stillborn piglets). Semen quality evaluation based on spermatozoa progressive motility, sperm concentration, morphological characteristics and chromatine structure damage were used to give recommendations for semen processing, dilution degree, prospective therapy of boars, or, at least, their culing. Analysis of semen was complemented with seasonal bacterial cultivation and controls in cases of sudden drop on semen quality. Separate fi les containing semen quality graphs and reproductive indicators for easier monitoring were created for every boar. Systematic semen analyses performed by the use of several modern methods, along with periodic bacteriological control, offer possibilities for reliable assessment of boars’ semen quality.
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JOYAL, S. M., B. W. KENNEDY, and J. N. WILKINS. "BOAR, BREED AND ENVIRONMENTAL EFFECTS ON MOTILITY OF FROZEN-THAWED SPERMATOZOA." Canadian Journal of Animal Science 66, no. 3 (September 1, 1986): 663–68. http://dx.doi.org/10.4141/cjas86-073.

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A total of 5186 ejaculates from 115 boars of five breeds (48 Yorkshire, 25 Landrace, 20 Duroc, 18 Hampshire and four Lacombe) were collected and frozen between 1975 and 1980. Frozen semen was thawed and evaluated for percentage progressive motile sperm (post-thaw rating) and loss in percentage motile sperm due to freezing and thawing. Boar repeatabilities and effects of breed of boar, year, month, age of boar at collection and percentage of extender added were examined. Boar repeatabilities were 0.32 for post-thaw rating and 0.22 for loss in percentage motile sperm. Breed of boar was not significant. Year was significant, and percentage motile sperm recovered declined from 1976 through 1980. Semen collected between March and May had the highest post-thaw rating. As age of boar increased, post-thaw rating declined and loss in percentage motile sperm increased. As the percentage of extender added to semen increased, so did the loss in percentage motile sperm after freezing. Correlations between post-thaw rating and fresh semen motility score, volume, concentration and percentage motile sperm were 0.24, 0.03, −0.20 and 0.25, respectively. Respective correlations of fresh semen measures with loss in percentage motile sperm after freezing were 0.15, 0.01, 0.17 and 0.23. The current practice of standardizing fresh semen to a given concentration before freezing does not result in a standard frozen-thawed product with respect to percentage motile sperm. Key words: Boar, semen, freezing, thawing, motility
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Moura, Anderson B., Alvimar J. Costa, Sérgio Jordão Filho, Beatriz B. Paim, Fernanda R. Pinto, and Daniela C. Di Mauro. "Toxoplasma gondii in semen of experimentally infected swine." Pesquisa Veterinária Brasileira 27, no. 10 (October 2007): 430–34. http://dx.doi.org/10.1590/s0100-736x2007001000008.

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Eight reproductive boars were divided into three groups and inoculated with Toxoplasma gondii [GI (n=3) 1.5x10(4) oocysts strain P; GII (n=3) 1.0x10(6) tachyzoites strain RH; and GIII (n=2) non-inoculated control]. Clinical, hematological, parasitemia and serological tests and studies of the parasite in the semen through bioassay and PCR, and in reproductive organs (Bioassay and immunohistochemical analyses) were conducted to evaluate the toxoplasmic infection. Blood and semen were collected on day -2, -1, 1, 3, 5, 7, 9, 11, 14 and weekly up to 84 days post-inoculation (DPI). No clinical or hematimetric alteration was observed in the boars. Parasitemia was detected in one boar inoculated with oocysts at the 7th DPI and in another boar infected with tachyzoites (GII) at the 3rd and 49th DPI. Serological tests revealed antibodies against T. gondii in animals inoculated with oocysts or tachyzoites at the 7th DPI with dilutions of 1:256 and 1:64, which reached peaks of 1:4096 at day 11 and 9, respectively. The bioassays revealed the presence of the parasite in semen samples of a boar inoculated with oocysts (GI) at 3, 49 and 56 DPI and from two boars infected with tachyzoites (GII), one animal at 5 and two animals at 49 days DPI. Mice inoculated with semen from the control group (GIII) remained serologically negative. PCR analysis showed T. gondii DNA in the semen of Boar 1 and Boar 3 inoculated with tachyzoites and oocysts, respectively. The immuno-histochemical tests showed T. gondii in the reproductive organs of Boar 1 and Boar 2, inoculated with tachyzoites and oocysts, respectively. These findings suggest the possible occurrence of venereal transmission of T. gondii in swine.
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Mazurova, J., R. Kukla, M. Rozkot, A. Lustykova, E. Slehova, R. Sleha, J. Lipensky, and L. Opletal. "Use of natural substances for boar semen decontamination." Veterinární Medicína 60, No. 5 (July 15, 2016): 235–47. http://dx.doi.org/10.17221/8175-vetmed.

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Dziekońska, A., and J. Strzeżek. "Boar variability affects sperm metabolism activity in liquid stored semen at 5°C." Polish Journal of Veterinary Sciences 14, no. 1 (December 1, 2011): 21–27. http://dx.doi.org/10.2478/v10181-011-0003-1.

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Boar variability affects sperm metabolism activity in liquid stored semen at 5°CMetabolic activity of boar spermatozoa, liquid stored for three days at 5°C, was measured using bioluminescence for ATP content, fluorescent assay (JC fluorochrome) of mitochondrial activity and oxygen consumption. Sperm motility and plasma membrane integrity (PMI) were simultaneously analyzed. Apart from the statistically significant effect (P < 0.001) of semen storage time, the importance of the individual source of the ejaculate for the analyzed parameters of metabolic efficiency of spermatozoa was shown. This phenomenon was manifested in the interaction of the individual source of the ejaculate with spermatozoa motility, integrity of their membranes and metabolic activity with the passing time of semen preservation. Recorded results indicate that the individual factor may have a significant influence on the technological usefulness of boar spermatozoa for liquid storage. Quality analyses conducted on boar semen stored at 5°C may be used for pre-selection of boars producing sperm with an enhanced tolerance to cold shock.
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Melendez, Ronald, O. MacPherson, J. A. Roden, S. A. Edwards, J. S. H. Hutchinson, A. G. Taylor, and P. R. English. "The effect of prostaglandin f2α on the production and quality of boar semen." Proceedings of the British Society of Animal Production (1972) 1991 (March 1991): 141. http://dx.doi.org/10.1017/s0308229600020912.

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The breeding boar is the single most important animal in the pig herd because he can sire very many piglets in a year, even moreso when used for AI. When a very superior boar is isolated following performance or progeny testing, good management and AI technology can be combined to exploit his potential. One possible way of making even more effective use of such a sire is through treatment of both the boar and his semen with analogues of prostaglandin F2α (PGF2α ). There have been reports from commercial practice of treatment of boars with PGF2a having desirable influences on libido, an increase in ejaculate volume and subsequent litter size in sows they serve. There have also been claims that when human semen is treated directly with an analogue of PGF2α sperm velocity increases. The purpose of this study was to further investigate the effects of PGF2 on semen production and semen quality of boars.
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Bryła, Magdalena, and Monika Trzcińska. "Relationship Between Apoptotic-Like Changes in Stored Boar Semen and DNA Fragmentation in Preimplantation Embryos." Annals of Animal Science 12, no. 3 (May 1, 2012): 357–66. http://dx.doi.org/10.2478/v10220-012-0030-6.

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Relationship Between Apoptotic-Like Changes in Stored Boar Semen and DNA Fragmentation in Preimplantation EmbryosThe aim of this experiment was to study the relationship between apoptotic-like changes in spermatozoa and DNA fragmentation in embryos obtained after insemination with fresh and stored semen. The ejaculates collected from three boars (five ejaculates from the same boar) were extended in Biosolwens Plus extender and stored for five days at 15-17°C. Semen, both fresh (Day 0) and stored (Day 5) used for insemination was analysed to detect apoptotic-like changes using fluorescence method: an assay to assess early changes in the membrane integrity of the sperm using the YO-PRO-1 fluorophore. After 5.5 days of insemination embryos were flushed out of the uterus and DNA fragmentation using TUNEL was analysed. In the fresh semen an average of 2.7, 3.7 and 6.2% of apoptotic sperm was observed in boar nos. 1, 2 and 3, respectively. After five days of storage the percentage of apoptotic sperm significantly increased up to 8.0, 15.7 and 23.2% in each analysed boar. The TUNEL index was 7.1% in the morphologically normal expanded blastocysts obtained after insemination with stored semen, and approximately 1.7% after insemination with fresh semen. A greater number of degenerated embryos and higher incidence of DNA fragmentation in the morphologically normal blastocysts were observed after insemination with stored semen which consists of higher percentage of apoptotic sperm compared to results from insemination with fresh semen.
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Christopher-Hennings, J., E. A. Nelson, J. K. Nelson, K. D. Rossow, J. L. Shivers, M. J. Yaeger, C. C. L. Chase, R. A. Garduno, J. E. Collins, and D. A. Benfield. "Identification of Porcine Reproductive and Respiratory Syndrome Virus in Semen and Tissues from Vasectomized and Nonvasectomized Boars." Veterinary Pathology 35, no. 4 (July 1998): 260–67. http://dx.doi.org/10.1177/030098589803500404.

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Previous studies have indicated that porcine reproductive and respiratory syndrome virus (PRRSV) can be identified in and transmitted through boar semen. However, the site(s) of replication indicating the origin of PRRSV in semen has not been identified. To determine how PRRSV enters boar semen, five vasectomized and two nonvasectomized PRRSV-seronegative boars were intranasally inoculated with PRRSV isolate VR-2332. Semen was collected three times weekly from each boar and separated into cellular and cell-free (seminal plasma) fractions. Both fractions were evaluated by reverse transcriptase nested polymerase chain reaction (RT-nPCR) for the presence of PRRSV RNA. Viremia and serostatus were evaluated once weekly, and boars were euthanatized 21 days postinoculation (DPI). Tissues were collected and evaluated by RT-nPCR, virus isolation (VI), and immunohistochemistry to identify PRRSV RNA, infectious virus, or viral antigen, respectively. PRRSV RNA was identified in semen from all vasectomized and nonvasectomized boars and was most consistently found in the cell fraction, within cells identified with a macrophage marker. Viral replication as determined by VI was predominately found within lymphoid tissue. However, PRRSV RNA was widely disseminated throughout many tissues, including the reproductive tract at 21 DPI. These results indicate that PRRSV can enter semen independent of testicular or epididymal tissues, and the source of PRRSV in semen is virus-infected monocytes/macrophages or non-cell-associated virus in serum. PRRSV-infected macrophages in semen may result from infection of local tissue macrophages or may originate from PRRSV-infected circulating monocytes or macrophages.
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S, Lazić. "Boar Quality Semen Testing and Presence of Mycoplasma Organism." Open Access Journal of Veterinary Science & Research 2, no. 3 (2017): 1–9. http://dx.doi.org/10.23880/oajvsr-16000137.

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This paper describes results of mycoplasma organism and Mycoplasma hyopneumoniae detection in semen of boars. During routine examination of semen quality in 2015 and 2016, different percent of specific changes in the spermatozoa of 23 b oars were observed and these samples were subjected to mycoplasma detection. The se changes were manifested as frequent distal midpiece reflex abnormalities with sporadic coiled principal piece; but booth loops were filed with fine, net like /reticular form s ( “ entrapped pseudocytoplasmatic droplet ” ). Based on the observed morphological forms i t is suspected on the presence and influence of microorganisms, primarily of Mycoplasma origin . PCR and real time PCR molecular methods were examined in all suspected s perm samples. The presence of Mycoplasma spp was found in 15 samples, of which, Mycoplasma hyopneumoniae was found in 8 samples. In the remaining seven samples differentiation to other mycoplasma species were not carried out . This article is indicating t hat genital form of mycoplasma could manifest its effect on semen quality and this may be more significant than current literature data are indicating and recogniz ing as problem in boars. In the same time, i ts high incidence in suspected semen samples coul d be more stressed as a source of sexually transmitted infection. Further estimation of Mycoplasma influence on boar semen quality is needed.
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Dissertations / Theses on the topic "Boar semen"

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Oh, Sang Hyon. "Estimation of Genetic Parameters for Boar Semen Traits." NCSU, 2003. http://www.lib.ncsu.edu/theses/available/etd-04182003-114352/.

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During the last half of the 20th century, the world pork industry has achieved astonishing developments in pig breeding. Now swine farms are larger, ownership more concentrated, and farms have become more industrialized. Artificial insemination (AI) plays an important role in animal breeding increasing utilization of genetically superior sires. Currently boars selected for commercial use as AI sires are evaluated on grow-finish performance and carcass characteristics. The objectives of this study were to (A) estimate genetic correlations between production and semen traits in the boar; average daily gain (ADG), back fat thickness (BF) and muscle depth (MD) as production traits, and total sperm cells (TSC), total concentration (TC), volume collected (SV), number of extended doses (ND), and acceptance rate of ejaculates (AR) as semen traits; (B) to model the variances and covariances of total sperm cells (× 109) over the active lifetime of AI boars; and (C) to compare multiple traits and random regression analyses applied to total sperm cells (TSC). Average heritability estimates were 0.39 for ADG, 0.32 for BF, 0.15 for MD, and repeatability estimates were 0.38 for SV, 0.37 for TSC, 0.09 for TC, 0.39 for ND, and 0.16 for AR. Semen traits showed negative genetic correlations with MD. Genetic correlations would indicate that current selection objectives are having a negative effect on semen traits. Therefore, current AI boar selection practices may be having a detrimental effect on semen production. In random regression analysis for total sperm cells, maximum log likelihood value was observed for sixth, fifth, and seventh order polynomials for fixed, additive genetic and permanent environmental effects, respectively. Best fit as determined by Akaike's Information Criterion was based on a model with sixth, fourth, and seventh order polynomials for fixed, additive genetic and permanent environmental effects, respectively. Best fit as determined by Schwarz Criterion was by fitting fourth, second, and seventh order polynomials for fixed, additive genetic and permanent environmental effects, respectively. Heritability estimates for total sperm cells ranged from 0.27 to 0.61 across age of boar classifications. Heritability for total sperm cells tended to increase with age of boar classification. The cyclic nature of heritability for total sperm cells that was observed over the active lifetime of boars may be due in part to number of observations across seasons limiting our ability to correct for seasonal effects on sperm production. In MTDFREML analysis, heritability estimates of 9, 12, 15, 18, 21, 24, and 27 months of age were, respectively, 0.28, 0.29, 0.26, 0.27, 0.30, 0.79, and 0.41. The results from MTDFREML seemed to be overestimated when compared to random regression. Therefore, random regression methods are the most appropriate to analyze semen traits as they are longitudinal data measured over the boars lifetime.
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Medrano, Hernandez Jose Alfredo. "The importance of individual variation in Boar semen cryopreservation." Thesis, Royal Veterinary College (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299995.

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Saravia, Fernando. "Deep freezing of concentrated boar semen for intra-uterine insemination /." Uppsala : Swedish University of Agricultural Sciences, 2004. http://epsilon.slu.se/9815944.pdf.

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Eriksson, Bengt. "Cryopreservation of boar semen : studies on sperm viability in vitro and fertility /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5903-6.pdf.

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Speight, Susan Michelle. "Growth Performance, Carcass Traits, and Reproductive Characteristics in Boars Fed Diets Supplemented With an Organic Source of Selenium." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/29584.

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The objectives of this study were to assess growth and reproductive performance of boars fed a diet supplemented with organic selenium (Se). Crossbred boars received one of three treatments: I. basal diet with no supplemental Se, II. basal diet supplemented with 0.3 ppm organic Se (Sel-Plex), and, III. basal diet supplemented with 0.3 ppm sodium selenite. Nursery (n = 13 pens/treatment) boar performance was not affected (P > 0.1) by diet and only grow-finish (n = 11 pens/treatment) G:F was greater (P < 0.06) for Sel-Plex (0.378) compared with selenite (0.368) or control (0.363) boars. At 15-mo of age semen was collected from boars (n = 10/treatment) over 5-d. Semen quality declined over time, but the negative impact day had on sperm motility was less pronounced with Sel-Plex boars. Effects of treatment x day were detected for progressively motile (P = 0.02) and rapidly moving (P = 0.03) spermatozoa, sperm path velocity (VAP; P = 0.05), and average velocity (VSL; P = 0.05). At 17-mo of age, semen was collected from boars (n = 10/treatment), extended and stored over 10-d. Although semen quality decreased over time, sperm from Sel-Plex boars resisted the negative effects of day on sperm motility and pH. Effects of treatment x day were detected for percent motile spermatozoa (P < 0.01), static spermatozoa (P < 0.01), VAP (P = 0.06), amplitude of head displacement (ALH; P = 0.02), straightness (P = 0.01), and pH (P < 0.01). At 23-mo of age, semen was collected (day 0) from boars (n = 6/treatment), extended, stored and evaluated at d 1 and 8 using in vitro fertilization. Dietary Se treatment failed to affect (P < 0.05) in vitro fertilizing rates of boars. In summary, dietary supplementation with Sel-Plex enhanced G:F in grow/finish boars. Dietary Sel-Plex supplementation may decrease the effects that stressors, such as intensive semen collection or semen storage, have on boar sperm characteristics such as sperm motility. The mechanisms for these responses remain to be elucidated.
Ph. D.
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Ekwall, Hans. "Electron microscopy of cryopreserved boar spermatozoa : with special reference to cryo-scanning electron microscopy and immunocytochemistry /." Uppsala : Dept. of Clinical Sciences, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/2007123.pdf.

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Kozink, Daniel Michael. "Enhancing Boar Reproductive Performance for Purposes of Artificial Insemination." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/46182.

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The objectives were to: 1) determine if im treatments of Lutalyse expedited the training of sexually inexperienced boars for semen collection and increased spermatozoal output, and 2) determine the effects of dietary L-carnitine supplementation on boar libido, semen quality, sperm production, and maintenance of sperm motility during liquid storage. Experiment 1 utilized lean-type, terminal-line boars (National Pig Development, Roanoke Rapids, NC) (n = 40; 177.4 ± 2.4 d of age and 112.8 ± 2.0 kg body weight) that had not previously experienced natural mating. Boars were individually moved twice weekly for 6 weeks (total of 12 training sessions) to a semen collection room equipped with an artificial sow. Upon entering the semen collection room, boars received in treatments of either deionized water (4 mL, n = 10) or Lutalyse at doses of 5 mg (n = 10), 10 mg (n = 10), or 20 mg (n = 10), and subsequently received a libido score of 1 to 5 (1 = no interest in the artificial sow; 5 = mounting the artificial sow and allowing semen collection). The percentages of boars successfully trained for semen collection during the experimental period were similar (P > 0.05) for controls (20%) and boars receiving 5 mg (30%), 10 mg (20%), or 20 mg (10%) of Lutalyse. Average libido score for boars receiving 10 mg Lutalyse (2.35 ± 0.08) was greater (P < 0.05) than for controls (2.14 ± 0.06). Libido score for the 20 mg treatment group were (1.78 ± 0.06) lower (P < 0.05) compared to the other treatment groups. Characteristics of ejaculates (volume, gel weight, sperm concentration, total spermatozoa) from control boars and boars treated with Lutalyse at doses of 5, 10, or 20 mg were similar (P > 0.05). For Exp. 2, the same group of boars was utilized in two similar trials (Trial 1, 1a, 1b: n = 9 for control and L-carnitine-treated boars; Trial 2, 2a, 2b: n = 10 for control and L-carnitine-treated boars). Boars were fed a fortified, corn and soybean meal-based diet at a rate of 2 kg/d. Boars that were randomly selected for L-carnitine treatment received the same diet mixed with L-carnitine to achieve supplementation of 500 mg/d. For 16 wk, semen was collected weekly via the gloved hand method and was analyzed for gel-free volume, gel weight, sperm concentration, sperm per ejaculate, and characteristics of sperm motility. Time to ejaculation (reaction time), duration of ejaculation, and number of false mounts were also recorded for each collection. Trials 1a and 2a were conducted during weeks 16 and 17 for each respective trial. Boars were collected once on 4 consecutive days, allowed 4 d of rest, and then collected again, to estimate daily spermatozoal production. At the end of 16 wk, a semen sample was also processed and extended in Beltsville Thawing Solution (BTS) to achieve a dilution of 3 x 109 spermatozoa/100 mL-dose for Trials 1b and 2b. The extended semen was stored in plastic bottles at 18°C and motility was evaluated daily for 7 d post collection. L-carnitine supplementation for 16 wk had no effects on semen volume, gel weight, total number of sperm cells per ejaculate, reaction time, or sperm motility (P > 0.1). Boars receiving the L-carnitine-supplemented diet displayed an increase in the number of false mounts before ejaculating and an increase in sperm concentration (P < 0.05) in Trial 2. A treatment by week interaction was detected for sperm concentration in Trial 2 (P < 0.005). Increased sperm concentrations in L-carnitine-treated boars were demonstrated after only one week of feeding the respective diets. Given that the production of a mature sperm cell requires 7 to 8 wk in boars, it is therefore difficult to conclude that differences in sperm concentration were due solely to treatment. Daily spermatozoal production was similar between control boars and boars supplemented with L-carnitine (P > 0.1) for both Trials 1a and 2a. L-carnitine supplementation did not affect percent motility in Trials 1b and 2b or sperm progressive motility in Trial 2b during 7 d storage (P > 0.1). A treatment by day interaction was determined for sperm velocity (P < 0.05) in Trial 2b. L-carnitine supplementation decreased mean sperm velocity significantly after 2 d of storage. Overall, L-carnitine had no beneficial effects on boar libido, semen quality, sperm production, or maintenance of sperm motility during liquid storage. However, Lutalyse increased libido scores, but did not affect the number of boars trained for semen collection or number of spermatozoa ejaculated.
Master of Science
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Hooper, Paul Nicholas. "The resistance of liquid extended boar semen to environmental stress encountered during air transport." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333488.

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Prieto, Martínez Noelia. "Aquaporins in boar and bull spermatozoa: identification and functional implications." Doctoral thesis, Universitat de Girona, 2017. http://hdl.handle.net/10803/405771.

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Aquaporins (AQPs) are proteins involved in the transport of water and some other solutes across plasma membranes. The fact that mammalian spermatozoa are highly permeable to water suggests the presence of these proteins. Taking into account that AQPs have been poorly studied in male germ cells, the present Thesis Dissertation is focused on the study of the presence, localisation and function of AQP3, AQP7 and AQP11 in the sperm of two major livestock species (porcine and bovine). On the one hand, this Thesis has demonstrated that these three proteins are found in different regions (head, neck or tail) of the ejaculated sperm in both species. On the other hand, this Dissertation has determined the relationship of the relative abundance of AQP3, AQP7 and AQP11 with sperm cryotolerance and in vitro fertilizing ability of frozen-thawed sperm. Following this, AQP3 and AQP7 have been found to be freezability markers in boar sperm, whereas AQP7 and AQP11 have been indentified to be crucial for bull sperm cryotolerance. Altogether, these results contribute to increase our knowledge about the function of these proteins in mammalian sperm and may also allow the selection of those fresh ejaculates that exhibit higher sperm cryotolerance.
Les aquaporines són proteïnes relacionades amb el transport d’aigua i altres soluts a través de les membranes plasmàtiques. El fet que l’espermatozoide madur de mamífer sigui una cèl·lula altament permeable a l’aigua suggereix la presència d’aquestes proteïnes. Tenint en compte que les aquaporines s’han estudiat més aviat poc en les cèl·lules germinals masculines, aquesta Tesi Doctoral s’ha centrat en l’estudi de la presència, localització i funció de les aquaporines 3, 7 i 11 en els espermatozoides de dues espècies d’interès productiu (porcina i bovina). D’una banda, aquest estudi ha demostrat que aquestes tres proteïnes es troben en diferents regions (cap, coll o cua) dels espermatozoides d’ambdues espècies. D’altra banda, aquesta Tesi també ha determinat que hi ha una relació entre la quantitat relativa d’aquestes proteïnes, la criotolerància de les ejaculacions i la capacitat fecundant in vitro després de la descongelació, de tal manera que es pot considerar que les AQP3 i AQP7 són marcadors de congelabilitat de l’esperma porcí i les AQP7 i AQP11 ho són de l’esperma boví. En conjunt, tots aquests resultats contribueixen a incrementar el nostre coneixement sobre el paper d’aquestes proteïnes en els espermatozoides de mamífer i permeten una millor selecció de les ejaculacions prèvia a la seva conservació.
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Casas, Roqueta Isabel. "A practical approach on boar sperm cryodamage. Morphofunctional and immunocytochemical study of cryopreserved boar sperm intended for use in artificial insemination." Doctoral thesis, Universitat de Girona, 2010. http://hdl.handle.net/10803/7642.

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L'ús d'esperma criopreservada en la inseminació artificial (IA) d'espècies d'interès productiu permet un major control sanitari i la creació de bancs de germoplasma d'alt valor genètic, entre d'altres avantatges. En el mercat porcí la major part de les inseminacions són encara realitzades amb semen refrigerat degut a l'èxit de l'aplicació de diluents de llarga durada i també a causa de la sensibilitat de l'esperma porcina a la criopreservació. Malgrat que aquesta sensibilitat ve donada per característiques particulars de la fisiologia espermàtica en l'espècie, algunes ejaculacions mantenen els paràmetres de qualitat espermàtica després de la criopreservació (ejaculacions amb bona "congelabilitat", GFEs) enfront d'altres que no sobreviuen al procés (ejaculacions amb mala "congelabilitat", PFEs). El primer objectiu de l'estudi va ser comparar ambdós grups en termes de fertilitat in vivo. El segon objectiu va ser testar l'eficiència de la inseminació postcervical (post-CAI) amb l'esperma criopreservada. El tercer objectiu va ser buscar predictors de la congelabilitat de les ejaculacions, tant en les GFEs com en les PFEs i en tres passos del procés de criopreservació (a 17ºC, a 5ºC i a 240 min postdescongelació). Aquest objectiu es va dur a terme mitjançant l'avaluació de paràmetres convencionals de qualitat espermàtica i a través de l'estudi de la localització i la reactivitat sota el microscopi de tres proteïnes (GLUT3, HSP90AA1 i Cu/ZnSOD) relacionades amb la fisiologia espermàtica i amb possibles rols en la congelabilitat. El quart objectiu va ser quantificar l'expressió de les tres proteïnes per transferència western, tant en espermatozoides d'ejaculacions GFEs com en els d'ejaculacions PFEs i en els tres passos abans esmentats, per tal de determinar el seu potencial com a predictores de la congelabilitat. Pel primer i el segon objectiu, 86 truges van ser inseminades per post-CAI amb 26 ejaculacions de mascles Piétrain dividides en una porció refrigerada a 17ºC (tractament control) i una porció criopreservada, ambdues porcions classificades alhora com a GFEs o PFEs. Els resultats més rellevants van demostrar que les probabilitats d'embaràs eren dues vegades menors en inseminacions amb esperma criopreservada d'ejaculacions PFEs (P < 0.05) que en inseminacions amb esperma criopreservada d'ejaculacions GFEs, fet que indica que les ejaculacions amb percentatges elevats d'espermatozoides mòbils progressius i d'integritat de membrana (per sobre del 40% en les GFEs) són més favorables a provocar embarassos que no pas aquelles ejaculacions amb una pobra funció espermàtica in vitro (PFEs). Ni el nombre de truges que van donar a llum, ni la quantitat de garrins, ni el risc de reflux espermàtic van ser significativament diferents entre les inseminacions amb esperma criopreservada d'ejaculacions GFEs i les inseminacions control amb semen refrigerat, la qual cosa demostra la bona aplicabilitat de la inseminació post-CAI amb l'esperma criopreservada. Finalment, pel tercer i quart objectius van ser criopreservades 29 i 11 ejaculacions de mascles Piétrain, respectivament. Dos paràmetres cinètics espermàtics, la linealitat (LIN) i la rectitud (STR), van mostrar una hiperactivació de la mobilitat superior en les ejaculacions PFEs que en les GFEs després de 30 min a 5ºC durant la criopreservació. A més, la combinació d'ambdós paràmetres va donar una fiabilitat propera al 72% en la predicció de la congelabilitat de les ejaculacions porcines. Tot i que no va ser possible predir la congelabilitat mitjançant l'avaluació de les tres proteïnes al microscopi, els resultats de transferència western van revelar diferències en l'expressió de la HSP90AA1 en l'esperma a 17ºC, molt possiblement relacionades amb la millor supervivència a la criopreservació dels espermatozoides d'ejaculacions GFEs. Aquests resultats suggereixen que la promoció de la criopreservació d'esperma porcina per la seva aplicació en IA passa pel desenvolupament de tests per la predicció de la congelabilitat en semen refrigerat.
The use of frozen-thawed (FT) sperm in artificial insemination (AI) of species with productive interest allows higher sanitary control and the creation of high genetic value sperm banks, among other advantages. In the swine market, most inseminations are still performed with refrigerated semen (FS) because of the successful application of long-term extenders and the sensitivity of boar sperm to cryopreservation. Although this sensitivity is provided by particular features of the sperm physiology in boars, some boar ejaculates maintain the sperm quality parameters after freezing (good freezability ejaculates, GFEs) in front of others that do not survive the process (poor freezability ejaculates, PFEs). The first objective of the study was to compare both groups in terms of field fertility. The second objective was to test the efficiency of the post-cervical AI (post-CAI) with FT sperm. The third objective was to search for predictors of the ejaculate freezability by assessing, both in GFEs and in PFEs and in three steps during the cryopreservation procedure (17ºC, 5ºC and 240 min post-thaw), conventional sperm quality parameters and the location and reactivity, under the microscope, of three proteins related to the sperm physiology with potential roles in freezability (GLUT3, HSP90AA1 and Cu/ZnSOD). The fourth objective was to quantify, through western blotting, the expression of the three proteins, both in GFEs and in PFEs and in the three steps mentioned, to determine their potential as freezability predictors. For the first and second objectives, 86 sows were inseminated by post-CAI with 26 ejaculates from Piétrain boars divided into a 17ºC FS portion (control treatment) and a cryopreserved (FT) sperm portion, the two portions in turn classified into GFEs and PFEs. The most relevant outcomes were that the probabilities of pregnancy resulted two times lower after inseminations with FT-PFEs (P < 0.05) compared to FT-GFEs, which indicates that ejaculates with high post-thaw sperm progressive motility and membrane integrity (over 40% in GFEs) are more likely to result in pregnancies than those with poor in vitro sperm function (PFEs). Neither the number of farrowing sows and the litter size nor the risk of sperm backflow was significantly different in FT-GFEs from that achieved in FS control treatments, which showed the good applicability of post-CAI to boar FT sperm. For the third and fourth objectives, 29 and 11 Piétrain boar ejaculates, respectively, were cryopreserved. Two kinematic indices, the sperm linearity (LIN) and the sperm straightness (STR), revealed higher hyperactivated motility in PFEs than in GFEs when assessed after 30 min at 5ºC during cryopreservation, the combination of the two motility parameters showing around 72% confidence in the freezability prediction of ejaculates. Whereas it was not possible to predict the freezability of the boar ejaculates by assessing the three proteins under microscope, results from western blot showed differences in the HSP90AA1 expression in sperm at 17ºC that are most possibly related to the best cryosurvival of GFEs. This finding aims to promote the cryopreservation of boar sperm intended for use in AI through the development of tests for freezability prediction in FS.
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Books on the topic "Boar semen"

1

A, Johnson Lawrence, and Rath Detlef, eds. Boar semen preservation 11: Proceedings of the 2nd International Conference on Boar Semen Preservation, held at United States Department of Agriculture, Agricultural Research Service, Beltsville, Maryland, August, 1990. Berlin: Paul Parey, 1991.

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Condon, Cian James. Effects of freezing or liquid storage on the viability and fertility of boar spermatozoa. Dublin: University College Dublin, 1998.

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Parsons, W. David. The best small-boat seamen in the Navy: The Newfoundland Division, Royal Naval Reserve, 1902-1921. St. John's, NL: DRC Pub., 2009.

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Parsons, W. David. The best small-boat seamen in the Navy: The Newfoundland Division, Royal Naval Reserve, 1902-1921. St. John's, NL: DRC Pub., 2009.

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Ean, Parsons, ed. The best small-boat seamen in the Navy: The Newfoundland Division, Royal Naval Reserve, 1902-1921. St. John's, NL: DRC Pub., 2009.

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Gunpowder, government, and war in the mid-eighteenth century. [London]: Royal Historical Society, 1991.

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Rogers, Hiromi T. Anjin - The Life and Times of Samurai William Adams, 1564-1620. GB Folkestone: Amsterdam University Press, 2016. http://dx.doi.org/10.5117/9781898823858.

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The year is 1600. It is April and Japan’s iconic cherry trees are in full flower. A battered ship drifts on the tide into Usuki Bay in southern Japan. On board, barely able to stand, are twenty-three Dutchmen and one Englishman, the remnants of a fleet of five ships and 500 men that had set out from Rotterdam in 1598. The Englishman was William Adams, later to be known as Anjin Miura by the Japanese, whose subsequent transformation from wretched prisoner to one of the Shogun’s closest advisers is the centrepiece of this book. As a native of Japan, and a scholar of seventeenth-century Japanese history, the author delves deep into the cultural context facing Adams in what is one of the great examples of assimilation into the highest reaches of a foreign culture. Her access to Japanese sources, including contemporary accounts – some not previously seen by Western scholars researching the subject – offers us a fuller understanding of the life lived by William Adams as a high-ranking samurai and his grandstand view of the collision of cultures that led to Japan’s self-imposed isolation, lasting over two centuries. This is a highly readable account of Adams’ voyage to and twenty years in Japan and that is supported by detailed observations of Japanese culture and society at this time. New light is shed on Adams’ relations with the Dutch and his countrymen, including the disastrous relationship with Captain John Saris, the key role likely to have been played by the munitions, including cannon, removed from Adams’ ship De Liefde in the great battle of Sekigahara (September 1600), the shipbuilding skills that enabled Japan to advance its international maritime ambitions, as well as the scientific and technical support Adams was able to provide in the refining process of Japan’s gold and silver.
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Contributors, Multiple. Exercise of the Small Arms and Great Guns, for the Seamen on Board His Majesty's Ships. Gale Ecco, Print Editions, 2018.

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N/A. EXERCISE OF THE SMALL ARMS AND GREAT GUNS FOR THE SEAMEN ON BOARD HIS MAJESTYOS SHIPS (1778). Naval & Military Press, 2004.

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Levi, Allan D., ed. Goodman's Neurosurgery Oral Board Review. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780190636937.001.0001.

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The purpose of this book is to educate and prepare neurosurgery candidates for the American Board of Neurological Surgery Oral Board Examination. The book begins by describing the format of the Oral Board Examination in the United States in its current format. It then examines some of the concepts and techniques in the question-and-answer process that forms the major premise of the Oral Board Examination. The book chapters that follow are divided into the neurosurgery subspecialty areas, including brain tumors, vascular, endovascular, cranial trauma, pain, epilepsy and functional, spine, peripheral nerve, pediatrics, and neurology. Each chapter contains three to seven case presentations. The cases are organized in a similar way that the Oral Board questions are presented. The authors of each chapter describe their ideal answer and provide a detailed analysis of each case. Key references are included in many chapters. Many of the chapter contributors are longstanding dedicated faculty members of the course and have taught the bi-annual offering for the past 15 years. All contributors have extensive experience in teaching for the boards and bring an unrivaled skill set to the book.
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Book chapters on the topic "Boar semen"

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González-Castro, Víctor, Rocío Alaiz-Rodríguez, Laura Fernández-Robles, R. Guzmán-Martínez, and Enrique Alegre. "Estimating Class Proportions in Boar Semen Analysis Using the Hellinger Distance." In Trends in Applied Intelligent Systems, 284–93. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-13022-9_29.

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Sánchez, Lidia, Nicolai Petkov, and Enrique Alegre. "Statistical Approach to Boar Semen Head Classification Based on Intracellular Intensity Distribution." In Computer Analysis of Images and Patterns, 88–95. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11556121_12.

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Dauscha, P. "The Future of the European Paper Industry as Seen by CEPAC." In Pulp, Paper and Board, 170–76. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-1345-5_24.

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Taylor, Becky. "‘Our Most Foreign Refugees’: Refugees from Vietnam in Britain." In When Boat People were Resettled, 1975–1983, 109–43. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-64224-2_4.

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AbstractBritain’s response to the ‘boat people’ crisis, as Becky Taylor shows in this chapter, had at its heart a contradiction. On the one hand, Margaret Thatcher’s government was keen to be seen as an ally of the US in the Cold War, and still a leader on the international stage. On the other, the arrival of 19,000 Vietnamese ‘boat people’ after 1979 came at a time of growing anti-immigration rhetoric, Britain’s deepest recession for fifty years and just as Thatcher’s New Right government’s marketisation and anti-statist policies were being enacted. This chapter explores how the tension between these different elements shaped Britain’s reception of the ‘boat people’, in particular pointing to the central place of voluntary organisations and multiculturalism in the resettlement programme.
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Haasis, Lucas. "5.3 The Writing Seamen: Learning to Write and Dictating Letters on Board the Bremen Ship “Concordia”." In Das Meer. Maritime Welten in der Frühen Neuzeit, 297–310. Köln: Böhlau Verlag, 2021. http://dx.doi.org/10.7788/9783412513122.297.

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Javier Henao, Francisco. "Relationship between Plasma Proteins and Boar Semen Freezability." In Animal Genetics - Approaches and Limitations. IntechOpen, 2019. http://dx.doi.org/10.5772/intechopen.75906.

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Caldevilla, Mariana, Alejandro Ferrante, Carlos Pendola, Maria Florencia Gallelli, Maria Veiga, and Marcelo Miragaya. "EFFECT OF THE ADDITION OF L-CARNITINE AND PYRUVATE ON BOAR SEMEN CRYOPRESERVATION." In Inovação e Pluralidade na Medicina Veterinária 3, 92–104. Atena Editora, 2020. http://dx.doi.org/10.22533/at.ed.84520110813.

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"Chapter Seven. Domination." In Across the Board, 95–112. Princeton: Princeton University Press, 2004. http://dx.doi.org/10.1515/9781400840922-008.

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"Seen from a Boat." In The Itineraries of Art, 175–99. Wilhelm Fink Verlag, 2015. http://dx.doi.org/10.30965/9783846757956_011.

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"8. Attitudes on the Pacific Coast: Franz Boas, Emily Carr, and Maisie Hurley." In Seen but Not Seen, 199–231. University of Toronto Press, 2021. http://dx.doi.org/10.3138/9781442622111-013.

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Conference papers on the topic "Boar semen"

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Morrell, J. M., and Margareta Wallgren. "Control of bacterial contamination in boar semen doses." In Proceedings of the International Conference on Antimicrobial Research (ICAR2010). WORLD SCIENTIFIC, 2011. http://dx.doi.org/10.1142/9789814354868_0059.

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"Kualitas Semen Cair Kambing Boer selama Penyimpanan Suhu Ruang dengan Penambahan Ekstrak Daun Kemangi (Ocimum sanctum)." In Teknologi Peternakan dan Veteriner Mendukung Kemandirian Pangan di Era Industri 4.0. Pusat Penelitian dan Pengembangan Peternakan, 2019. http://dx.doi.org/10.14334/pros.semnas.tpv-2019-p.334-344.

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Li, Yansen, Zhaojian Li, Jiaqin Chen, and Chunmei Li. "High ambient temperature impacts semen quality in boars and potential molecular drug-targets and nutritional strategies for amelioration." In 10th International Livestock Environment Symposium (ILES X). St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2018. http://dx.doi.org/10.13031/iles.18-077.

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Sitepu, Sukma Aditya, Zaituni Udin, Jaswandi, and Hendri. "The Effect of Combination Sweet Orange Peel Essential Oil with Trish Yolk and Streptomycin Extender on the Quality Boer Goat Liquid Semen." In 3rd International Conference of Computer, Environment, Agriculture, Social Science, Health Science, Engineering and Technology. SCITEPRESS - Science and Technology Publications, 2018. http://dx.doi.org/10.5220/0010044404370441.

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López, Juan David, and Carlos Francisco Rodríguez. "Design of a Boat Simulator Using Two Parallel Manipulators." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-38162.

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In this paper a boat simulator is designed using parallel manipulators. The simulator allows the training of five or seven people in a river environment. Due to the high payload and high inertial forces, it was proposed to divide the simulator into various synchronized platforms. Additionally different configurations of mechanisms were evaluated as well as linear or rotational actuation. The dimensional synthesis was performed by introducing a power index based on the Virtual Work equations of motion, and applying Genetic Algorithms for optimization. This design process results in using two coordinated manipulators with rotational actuators. The first one has two degrees of freedom (pitch and roll); it will simulate the motion of the boat’s stern. The second one has three degrees of freedom: pitch, roll and heave; and simulates the motion of the boat’s bow. The detail design was concluded and the manipulators were built. A real time controller is under design nowdays and the integration of the fluid and the boat dynamics into the inverse dynamics analysis of the manipulators is proposed as future work.
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Serck-Hanssen, Bjo̸rn, and Ove T. Gudmestad. "Hyperbaric Evacuation in the North." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49243.

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In this paper we will look into Hyperbaric Evacuation in the Arctic and Cold Climate regions and particularly in the Barents Sea. By hyperbaric evacuation is meant all means for safe transportation of the divers in saturation until decompressed onshore. Further the hyperbaric life boat on Subsea 7’s Diving Support Vessel (DSV) Seven Havila is investigated for use in these areas and the potential limitations the existing design has on diving operations in the area will be discussed.
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Yang, H., and L. He. "Experiment on Linear Compressor Cascade With 3-D Blade Oscillation." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38484.

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An experiment has been carried out to enhance the understanding of 3D blade aeroelastic mechanisms and to produce test data of realistic configurations for validation of advanced 3D aeromechanical methods. A low speed rig with a compressor cascade consisting of seven prismatic blades of controlled diffusion profile has been commissioned. The middle blade is mechanically driven to oscillate in a 3D bending/flapping mode. At a nominal steady flow condition unsteady pressure measurements were performed at six spanwise sections for three different reduced frequencies and two different tip-clearance gaps. Off-board pressure transducers were utilized in conjunction with a transfer-function method to correct tubing distortion errors. The linearity of aerodynamic response is confirmed by the tests with different blade oscillation amplitudes, which enables the tuned cascade results to be constructed by using the Influence Coefficient Method. The measured results illustrate fully three-dimensional unsteady behaviour. Strong spanwise unsteady interaction leads to a non-proportional distribution of pressure amplitude at different spanwise locations. The tests with different tip-clearance gaps (1–2% span) show that the near tip region is destabilised as the tip gap is increased. This may be attributed to the local unloading of the corresponding steady flow. The destabilised region is seen to extend to approximately 20% of the blade span. The total aerodynamic damping at the least stable inter-blade phase angle has been reduced by 27%, when the tip gap is increased from nearly zero to 2% span.
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Kaprielian, Gabriel. "Design as Play: Sea-Level Rise Planning Board Game." In 2018 ACSA International Conference. ACSA Press, 2018. http://dx.doi.org/10.35483/acsa.intl.2018.39.

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The waterfront along the San Francisco Bay is facing a growing threat from sea-level rise. Over the years, the Bay Area has seen a large portion of the historic wetlands filled or leveled off for residential, commercial, and industrial land uses. According to current sea level rise projections, water will once again reclaim the bay lands that have been filled. The issues presented by sea level rise along the urban edge of the San Francisco Bay involve a complex series of challenges including: regional versus local governance, built versus natural environment, vulnerable local and regional infrastructure, diverging interests with diverse stakeholders, and population growth. With each possible future scenario come multiple outcomes with winners and losers. How can the best policy and design be selected and tested? How will distinct communities learn about different options and strategies for adaptation and be empowered to act? By creating and playing a sea level rise adaptation “game,” student were able to explore these different scenarios and inform future urban planning and design decisions.
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Kulkarni, Amit, Dereje Agonafer, Steven Groothuis, Humayun Kabir, and Scott Johnson. "Package and Board Level Study for a Thin Small Outline Package (TSOP) Using Compact Components." In ASME 2003 International Electronic Packaging Technical Conference and Exhibition. ASMEDC, 2003. http://dx.doi.org/10.1115/ipack2003-35279.

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A detail model of 54 lead Thin Small Outline Package (TSOP) was created in Flotherm and validated against experimental data for natural convection and forced convection environments. Next, a compact two-resistor (2R) model was created in Flotherm using compact smart parts. Values of junction-to-case and junction-to-board resistances were taken from experiments. Both the detailed model and the compact model were mounted on a 4-layered standard JEDEC board for natural convection in a standard JEDEC enclosure. With a nominal power of 0.75W applied at the junction, the detailed model and the 2R compact model showed a very good agreement. The results also compared well with experimental data. Next, two models were developed; a detailed model and a corresponding equivalent 2R compact model were mounted on a 4-layered standard JEDEC board and simulated for forced convection with an air velocity of 1 m/s. With a nominal power of 0.75 W applied at the junction, maximum junction temperatures were computed and once again showed very good agreement. Experimental data for forced convection indicated that the maximum junction temperature was in good agreement to the compact model. The study was further extended to do a board level analysis where the detailed TSOP models were mounted on a 6-layered standard DIMM board. In the single sided board arrangement nine such compact models were mounted on one side of the board and maximum junction temperature was noted. Then, the detailed models were replaced by compact models and simulated for forced convection with an air velocity of 1 m/s. Good agreement between detailed model and compact model was seen for the board level analysis. Further the compact models were simulated for a double-sided arrangement in which eighteen such compact models were mounted nine on each sided of the board. The assembly was simulated for forced convection with an air velocity of 1 m/s. Nominal power applied at junction for each of the eighteen modules was 0.3 W. Maximum temperature for the double sided arrangement of DIMM board was thus computed.
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Liu, Song, and Bin Yao. "On-Board System Identification of Systems With Unknown Input Nonlinearity and System Parameters." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79420.

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Input nonlinearities, or actuator nonlinearities, can be seen in a lot of systems and have significant effects on the system performance. From the controller design point of view, accurate yet simple model of input nonlinearities is essential to compensate their effects and to achieve high level control performance. Unfortunately, most input nonlinearities are neither known nor easy to characterize, especially when the input nonlinearities and unknown system parameters are present simultaneously in the system dynamics. Off-board calibration may be possible yet it is very time consuming and requires additional calibration systems. This paper focuses on a class of systems with unknown input nonlinearities and system parameters and proposes an on-board system identification process to model the unknown nonlinearities. The input nonlinearities are decomposed into localized orthogonal basis and then estimated together with the system parameters. The proposed method is applied to model the nonlinear flow mapping of cartridge valves. Simulation and experimental results are obtained to illustrate the effectiveness and practicality of the proposed method.
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