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Sample records for induce sheep twinning

  1. Serum mineral levels at pregnancy and postpartum in single and twin pregnant sheep.

    Science.gov (United States)

    Yildiz, Atilla; Balikci, Engin; Gurdogan, Fuat

    2005-12-01

    This study was performed to investigate calcium (Ca), inorganic phosphorus (P), potassium (K), magnesium (Mg), and chlorine (Cl) levels in blood serum at d 60, 100, and 150 of gestation and at d 45 after parturition and to find out the significance of differences for macromineral levels during these stages of single or twin gestation in Akkaraman sheep. Blood samples of 30 apparently healthy pregnant Akkaraman sheep (15 single pregnancies, 15 twin pregnancies) were used. The samples were analyzed using a biochemical analyzer for Ca, P, Na, K, and Mg concentrations and using the Schales method for Cl levels. A statistically significant decrease (p pregnancy for Ca levels and for serum inorganic P levels in both groups. Twin pregnant sheep were found to have lower (p 0.05, p pregnancy. There were significant increases (p < 0.01) in serum Cl levels on d 100 in single and twin pregnant sheep.

  2. Failure of vincristine induce twinning

    Science.gov (United States)

    Binder, M.

    1984-01-01

    Mammalian ova do not contain axes of symmetry from which are derived embryonic axes of symmetry. Mammalian axis determination is an early embryologic event occurring at about the time that monozygous twinning in mice. (Kaufma MH & O'Shea KS, 1978, Nature 276:707) and an attempt was made to reproduce their work in several strains of mice. Over 3200 embryos were examined without any twins being found. To rule out the possibility that vincristine caused twinning plus some lethal malformation (with subsequent resorption of the embryo) the embryos were examined 36-60 hours after vincristine treatment.

  3. OSTEOPENIA in cancellous bone of sheep induced by Glucocorticoid alone

    DEFF Research Database (Denmark)

    Ding, Ming; Cheng, L.; Bollen, Peter;

    2008-01-01

    Introduction: There is a great need for suitable large animal models that closely resemble osteoporosis in humans, and that they have adequate bone size for bone prosthesis and biomaterial research. Previous investigations have shown that osteoporotic sheep model requires glucocorticoid (GC......) treatment for a long period of time after ovariectomy (OVX) to induce osteoporosis (1). However, no information in literature is available whether osteoporosis (OP) in sheep can be induced by application of GC alone. This study aimed to investigate effects of GC alone without OVX on three-dimensional (3-D......) microarchitectural properties and mechanical properties of sheep cancellous bone after a 7 months steroid treatment; and thus to validate a large animal model for orthopaedic implant/biomaterial research. Materials and Methods: Eighteen female sheep were randomly allocated into 3 groups: group 1 (GC-1) received GC...

  4. Microstructural evolution in deformed austenitic TWinning Induced Plasticity steels

    NARCIS (Netherlands)

    Van Tol, R.T.

    2014-01-01

    This thesis studies the effect of plastic deformation on the stability of the austenitic microstructure against martensitic transformation and diffusional decomposition and its role in the phenomenon of delayed fracture in austenitic manganese (Mn)-based TWinning Induced Plasticity (TWIP) steels. Th

  5. In Situ Studies on the Irradiation-Induced Twin Boundary-Defect Interactions in Cu

    Science.gov (United States)

    Fan, C.; Li, Jin; Fan, Zhe; Wang, H.; Zhang, X.

    2017-08-01

    Polycrystalline Cu films with nanoscale annealing twins are subjected to in situ Kr++ ion irradiation at room temperature inside a transmission electron microscope up to a dose of 1 displacement-per-atom. Radiation induces prominent migration of incoherent twin boundaries. Depending on twin thickness, three types of twin boundary evolutions are observed, including rapid detwinning, gradual detwinning, and self-healing. The mechanism of twin thickness-dependent evolution of microstructures is discussed. This study provides further evidence on twin boundary-defect interactions and may assist the design of radiation-tolerant twinned metallic materials.

  6. Cartilage Regeneration by Chondrogenic Induced Adult Stem Cells in Osteoarthritic Sheep Model: e98770

    National Research Council Canada - National Science Library

    Chinedu C Ude; Shamsul B Sulaiman; Ng Min-Hwei; Chen Hui-Cheng; Johan Ahmad; Norhamdan M Yahaya; Aminuddin B Saim; Ruszymah B H Idrus

    2014-01-01

    ...), multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model...

  7. Nitrogen dioxide-induced acute lung injury in sheep.

    Science.gov (United States)

    Januszkiewicz, A J; Mayorga, M A

    1994-05-20

    Lung mechanics, hemodynamics and blood chemistries were assessed in sheep (Ovis aries) before, and up to 24 h following, a 15-20 min exposure to either air (control) or approximately 500 ppm nitrogen dioxide (NO2). Histopathologic examinations of lung tissues were performed 24 h after exposure. Nose-only and lung-only routes of exposure were compared for effects on NO2 pathogenesis. Bronchoalveolar lavage fluids from air- and NO2-exposed sheep were analyzed for biochemical and cellular signs of NO2 insult. The influence of breathing pattern on NO2 dose was also assessed. Five hundred ppm NO2 exposure of intubated sheep (lung-only exposure) was marked by a statistically significant, albeit small, blood methemoglobin increase. The exposure induced an immediate tidal volume decrease, and an increase in both breathing rate and inspired minute ventilation. Pulmonary function, indexed by lung resistance and dynamic lung compliance, progressively deteriorated after exposure. Maximal lung resistance and dynamic lung compliance changes occurred at 24 h post exposure, concomitant with arterial hypoxemia. Bronchoalveolar lavage fluid epithelial cell number and total protein were significantly increased while macrophage number was significantly decreased within the 24 h post-exposure period. Histopathologic examination of lung tissue 24 h after NO2 revealed patchy edema, mild hemorrhage and polymorphonuclear and mononuclear leukocyte infiltration. The NO2 toxicologic profile was significantly attenuated when sheep were exposed to the gas through a face mask (nose-only exposure). Respiratory pattern was not significantly altered, lung mechanics changes were minimal, hypoxemia did not occur, and pathologic evidence of exudation was not apparent in nose-only, NO2-exposed sheep. The qualitative responses of this large animal species to high-level NO2 supports the concept of size dependent species sensitivity to NO2. In addition, when inspired minute ventilation was used as a dose

  8. Interleukin-1 in Lipopolysaccharide Induced Chorioamnionitis in the Fetal Sheep

    Science.gov (United States)

    Berry, Clare A.; Nitsos, Ilias; Hillman, Noah H.; Pillow, J. Jane; Polglase, Graeme R.; Kramer, Boris W.; Kemp, Matthew W.; Newnham, John P.; Jobe, Alan H.; Kallapur, Suhas G.

    2011-01-01

    We tested the hypothesis that interleukin 1 (IL-1) mediates intra-amniotic lipopolysaccharide (LPS)-induced chorioamnionitis in preterm fetal sheep. Time-mated Merino ewes with singleton fetuses received IL-1α, LPS, or saline (control) by intra-amniotic injection 1 to 2 days before operative delivery at 124 ± 1 days gestational age (N = 5-9/group; term = 150 days). Recombinant human IL-1 receptor antagonist (rhIL-1ra) was given into the amniotic fluid 3 hours before intra-amniotic LPS or saline to block IL-1 signaling. Inflammation in the chorioamnion was determined by histology, cytokine messenger RNA (mRNA), protein expression, and by quantitation of activated inflammatory cells. Intra-amniotic IL-1 and LPS both induced chorioamnionitis. However, IL-1 blockade with IL-1ra did not decrease intra-amniotic LPS-induced increases in pro-inflammatory cytokine mRNAs, numbers of inflammatory cells, myeloperoxidase, or monocyte chemotactic protein-1-expressing cells in the chorioamnion. We conclude that IL-1 and LPS both can cause chorioamnionitis, but IL-1 is not an important mediator of LPS-induced chorioamnionitis in fetal sheep. PMID:21493953

  9. Tensile Properties of Cu with Deformation Twins Induced by SMAT

    Institute of Scientific and Technical Information of China (English)

    Jinyu GUO; Ke WANG; Lei LU

    2006-01-01

    High density nano-scale deformation twins were introduced in the surface layer of Cu sample by means of surface mechanical attrition treatment (SMAT) at room temperature. The Cu sample with deformation twins shows a yield strength of about 470 MPa in tension tests. The significant strengthening may be attributed to the effective inhibition of slip dislocations by abundant twin boundaries.

  10. Exposure of bighorn sheep to domestic goats colonized with Mycoplasma ovipneumoniae induces sub-lethal pneumonia.

    Science.gov (United States)

    Besser, Thomas E; Cassirer, E Frances; Potter, Kathleen A; Foreyt, William J

    2017-01-01

    Bronchopneumonia is a population limiting disease of bighorn sheep (Ovis canadensis) that has been associated with contact with domestic Caprinae. The disease is polymicrobial but is initiated by Mycoplasma ovipneumoniae, which is commonly carried by both domestic sheep (O. aries) and goats (Capra aegagrus hircus). However, while previous bighorn sheep comingling studies with domestic sheep have resulted in nearly 100% pneumonia mortality, only sporadic occurrence of fatal pneumonia was reported from previous comingling studies with domestic goats. Here, we evaluated the ability of domestic goats of defined M. ovipneumoniae carriage status to induce pneumonia in comingled bighorn sheep. In experiment 1, three bighorn sheep naïve to M. ovipneumoniae developed non-fatal respiratory disease (coughing, nasal discharge) following comingling with three naturally M. ovipneumoniae-colonized domestic goats. Gross and histological lesions of pneumonia, limited to small areas on the ventral and lateral edges of the anterior and middle lung lobes, were observed at necropsies conducted at the end of the experiment. A control group of three bighorn sheep from the same source housed in isolation during experiment 1 remained free of observed respiratory disease. In experiment 2, three bighorn sheep remained free of observed respiratory disease while comingled with three M. ovipneumoniae-free domestic goats. In experiment 3, introduction of a domestic goat-origin strain of M. ovipneumoniae to the same comingled goats and bighorn sheep used in experiment 2 resulted in clinical signs of respiratory disease (coughing, nasal discharge) in both host species. At the end of experiment 3, gross and histological evidence of pneumonia similar to that observed in experiment 1 bighorn sheep was observed in both affected bighorn sheep and domestic goats. M. ovipneumoniae strains carried by domestic goats were transmitted to comingled bighorn sheep, triggering development of pneumonia. However

  11. Electronic structures and optical properties induced by silicon twin boundaries: The first-principle calculation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.X.; Liu, L.Z. [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics and Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Wu, X.L., E-mail: hkxlwu@nju.edu.cn [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics and Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Department of Physics, NingBo University, NingBo 315301 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

    2015-07-03

    The defect states and optical absorption enhancement induced by twin boundaries in silicon are investigated by first-principle calculation. The defect states in the forbidden bands are identified and based on the established electronic structures, the dielectric functions and absorption coefficients are derived. An important result of our calculations is that visible light absorption by the twinning configuration is enhanced significantly, indicating that twinning structures possibly play an important role in silicon-based photovoltaic devices. - Highlights: • Defect states and optical absorption enhancement induced by twin boundaries in silicon are investigated theoretically. • Dielectric functions and absorption coefficients are derived. • Enhanced visible light absorption by the twinning configuration is demonstrated. • Twinning structures play an important role in silicon-based photovoltaic devices.

  12. Postmortem biochemical markers of experimentally induced hypomagnesaemic tetany in sheep.

    Science.gov (United States)

    McCoy, M A; Bingham, V; Hudson, A J; Cantley, L; Hutchinson, T; Davison, G; Fitzpatrick, D A; Kennedy, D G

    2001-02-24

    Hypomagnesaemic tetany was induced in non-lactating and lactating ewes by feeding them semi-synthetic low magnesium diets containing additional potassium chloride and citric acid. Aqueous and vitreous humour were sampled from one eye at the time of death (fresh) and from the second eye after the head had been stored at ambient temperature for 24 hours (24-hour). There were significant relationships between the concentrations of magnesium in cerebrospinal fluid and plasma and its concentrations in fresh aqueous humour and fresh vitreous humour. Magnesium concentrations of tetany. However, the concentration of magnesium in aqueous humour is relatively unstable and, unless the time of death was known accurately, its interpretation would be difficult. Magnesium concentrations of tetany in adult sheep. The concentration of magnesium in vitreous humour was relatively stable for up to 48 hours postmortem.

  13. Twinning interactions induced amorphisation in ultrafine silicon grains

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Y. [School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Zhang, L.C., E-mail: liangchi.zhang@unsw.edu.au [School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Zhang, Y. [School of Mechatronics Engineering, Harbin Institute of Technology (China)

    2016-03-21

    Detailed transmission electron microscopy analysis on a severely deformed Al-Si composite material has revealed that partial dislocation slips and deformation twinning are the major plastic deformation carriers in ultrafine silicon grains. This resembles the deformation twinning activities and mechanisms observed in nano-crystalline face-centred-cubic metallic materials. While deformation twinning and amorphisation in Si were thought unlikely to co-exist, it is observed for the first time that excessive twinning and partial dislocation interactions can lead to localised solid state amorphisation inside ultrafine silicon grains.

  14. Incoherent twin boundary migration induced by ion irradiation in Cu

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.; Misra, A. [Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Wang, J.; Wang, Y. Q. [Materials Science and Technology Division, MST-8, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Serruys, Y. [CEA, DEN, Service de Recherches de Metallurgie Physique, Laboratoire JANNUS, F-91191 Gif-sur-Yvette (France); Nastasi, M. [Nebraska Center for Energy Sciences Research, University of Nebraska, Lincoln, Nebraska 68588 (United States)

    2013-01-14

    Grain boundaries can act as sinks for radiation-induced point defects. The sink capability is dependent on the atomic structures and varies with the type of point defects. Using high-resolution transmission electron microscopy, we observed that {Sigma}3{l_brace}112{r_brace} incoherent twin boundary (ITB) in Cu films migrates under Cu{sup 3+} ion irradiation. Using atomistic modeling, we found that {Sigma}3{l_brace}112{r_brace} ITB has the preferred sites for adsorbing interstitials and the preferential diffusion channels along the Shockley partial dislocations. Coupling with the high mobility of grain boundary Shockley dislocations within {Sigma}3{l_brace}112{r_brace} ITB, we infer that {Sigma}3{l_brace}112{r_brace} ITB migrates through the collective glide of grain boundary Shockley dislocations, driven by a concurrent reduction in the density of radiation-induced defects, which is demonstrated by the distribution of nearby radiation-induced defects.

  15. Duration of an induced resistance of sheep to acute poisoning by Crotalaria retusa seeds

    Directory of Open Access Journals (Sweden)

    Lisanka Angelo Maia

    2014-06-01

    Full Text Available The aim of this study was to determine the duration of the resistance after the end of the ingestion of non-toxic doses of Crotalaria retusa seeds. Ten sheep were divided into 3 groups of 3 animals each and a control group with 1 sheep. To induce resistance, sheep in groups 1, 2 and 3 received 20 daily doses of 2g kg-1 of C. retusa seeds, followed by 7 daily doses of 4g kg-1. To determine the duration of resistance the sheep in groups 1, 2 and 3 were challenged orally, 3, 7 and 15 days, respectively, after receiving the last dose of 4g kg-1, with a single dose of 5g kg-1. Sheep of groups 1 and 2 did not develop overt signs of poisoning. Two sheep of group 3, challenged 15 days after the end of the resistance induction period, showed signs of acute poisoning and died. These results suggest that the induced resistance of sheep to acute poisoning by C. retusa seeds is of short duration, from 7 to 15 days.

  16. The formation of radiation-induced segregation at twin bands in ion-irradiated austenitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyung-Ha; Lee, Gyeong-Geun; Kwon, Junhyun; Hwang, Seong Sik [Nuclear Materials Division, Korea Atomic Energy Research Institute, 1045 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Shin, Chansun, E-mail: c.shin@mju.ac.kr [Department of Materials Science and Engineering, Myongji University, 116 Myongji-ro, Cheoin-gu, Youngin, Gyeonggi-do 449-728 (Korea, Republic of)

    2014-11-15

    Radiation-induced segregation (RIS) at twins was investigated using transmission electron microscopy (TEM) for ion-irradiated austenitic stainless steel. Significant RIS was found to occur at twin boundaries. TEM analysis indicates that interfacial dislocations at partially coherent twin boundaries are potential sites for strong RIS phenomenon. The RIS causes the formation of thin bands having a higher Ni and lower Cr concentration in twin bands with a width less than 15 nm. In wider twin bands, strong RIS occurs only at the outer twin boundaries, but not inside the band. The possible mechanism for the formation of the RIS thin band is discussed.

  17. Periconceptional undernutrition and being a twin each alter kidney development in the sheep fetus during early gestation.

    Science.gov (United States)

    MacLaughlin, Severence M; Walker, Simon K; Kleemann, David O; Tosh, Darran N; McMillen, I Caroline

    2010-03-01

    Adaptive growth responses of the embryo and fetus to nutritional restraint are important in ensuring early survival, but they are implicated in the programming of hypertension. It has been demonstrated that kidney growth and nephrogenesis are each regulated by intrarenal factors, including the insulin-like growth factors, glucocorticoids, and the renin-angiotensin system. Therefore, we have investigated the impact of periconceptional undernutrition (PCUN; from approximately 6 wk before to 7 days after conception) in singleton (control, n = 18; PCUN, n = 16) and twin pregnancies (control, n = 6; PCUN, n = 5) on the renal mRNA expression of 11beta- hydroxysteroid dehydrogensase type 1 and type 2 (11beta-HSD-1 and -2), the glucocorticoid (GR), and mineralocorticoid receptors, angiotensinogen, angiotensin receptor type 1 (AT1R) and 2 (AT2R), IGF-1 and IGF-2, and IGF1R and IGF2R at approximately 55 days gestation. There was no effect of PCUN or fetal number on fetal weight on relative kidney weight at approximately day 55 of gestation. There was an inverse relationship between the relative weight of the fetal kidney at approximately day 55 and maternal weight loss during the periconceptional period in fetuses exposed to PCUN. Exposure to PCUN resulted in a higher expression of IGF1 in the fetal kidney in singleton and twin pregnancies. Being a twin resulted in higher intrarenal expression of IGF-1 and IGF-2, GR, angiotensinogen, AT1R, and AT2R mRNA at 55 days gestation. Renal 11beta-HSD-2 mRNA expression was higher in PCUN singletons, but not PCUN twins, compared with controls. Thus, there may be an adaptive response in the kidney to the early environment of a twin pregnancy, which precedes the fetal growth restriction that occurs later in pregnancy. The kidney of the twin fetus exposed to periconceptional undernutrition may also be less protected from the consequences of glucocorticoid exposure.

  18. Activity of closantel against experimentally induced Fascioloides magna infection in sheep.

    Science.gov (United States)

    Stromberg, B E; Schlotthauer, J C; Seibert, B P; Conboy, G A; Newcomb, K M

    1985-12-01

    The efficacy of closantel against experimentally induced Fascioloides magna infection in sheep was studied. In each of 3 experiments, closantel was administered 8 weeks after the sheep were given (oral inoculation) 100 metacercariae of F magna. In the 1st experiment, closantel was given orally to 5 groups of 6 sheep each at dosages of 0 (nontreated control), 5, 7.5, 10, and 15 mg/kg of body weight. In the 2nd and 3rd experiments, groups of 10 or 12 sheep were treated to confirm the efficacy of the previously determined optimal dosage of 15 mg/kg. An additional group of sheep (n = 10) was used in the 3rd experiment to evaluate the efficacy of closantel given IM at a dosage of 7.5 mg/kg. Closantel given orally at a dosage level of 15 mg/kg was highly effective (94.6% to 97.7%) in reducing F magna burdens. Also, pathologic scores associated with the F magna infection were reduced by 81.3% to 92.6% in sheep given this dosage of closantel. Efficacy of the IM administered dosage of 7.5 mg of drug/kg was equivalent to that of the 15 mg/kg oral dosage. Other than mild, transient lameness of the limbs which were injected with the drug (group 10), side effects were not observed.

  19. Confined blood chimerism in a monochorionic dizygotic sex discordant twin pregnancy conceived after induced ovulation.

    Science.gov (United States)

    Mayeur Le Bras, Anne; Petit, François; Benachi, Alexandra; Bedel, Bettina; Oucherif, Salima; Martinovic, Jelena; Armanet, Narjes; Tosca, Lucie; Gautier, Valérie; Parisot, Frédéric; Labrune, Philippe; Tachdjian, Gérard; Brisset, Sophie

    2016-04-01

    Monochorionic twins are generally considered as a monozygotic twin pregnancy. However, several cases of monochorial dizygotic twin pregnancies have been reported. We report on a rare case of monochorionic dizygotic twin pregnancy conceived after induced ovulation in a 32-year-old woman. The diagnosis was made on morphological ultrasound examination at 18+4 weeks of gestation, showing two fetuses with discordant sex. The amniocentesis was declined by the patient. The monochorionic status was confirmed after a histopathalogical study of the placenta. At delivery, both a phenotypically normal boy and a phenotypically normal girl without sexual abnormality were observed. This analysis also revealed the presence of vascular anastomoses between both fetal circulations. Postnatal cytogenetic analyses indicated the presence of a chimerism in peripheral blood lymphocytes. This chimerism was not observed in cells obtained from a buccal swab. Molecular determination of zygosity confirmed the existence of the confined peripheral blood chimerism with the presence of four parental alleles. We report on a case of monochorionic dizygotic twin pregnancy. This observation underlies the need to carefully assess twin pregnancies, especially when obtained after assisted reproductive technology. © 2016 Wiley Periodicals, Inc.

  20. Microstructural evolution and deformation behavior of twinning-induced plasticity (TWIP) steel during wire drawing

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Joong-Ki [Graduate Institute of Ferrous Technology, POSTECH, Pohang 790-784 (Korea, Republic of); Steel Products Research Group, Technical Research Laboratories, POSCO, Pohang 790-785 (Korea, Republic of); Yi, Il-Cheol [Graduate Institute of Ferrous Technology, POSTECH, Pohang 790-784 (Korea, Republic of); Son, Il-Heon; Yoo, Jang-Yong [Steel Products Research Group, Technical Research Laboratories, POSCO, Pohang 790-785 (Korea, Republic of); Kim, Byoungkoo [Materials Technology Development Team, DHIC, Changwon 642-792 (Korea, Republic of); Zargaran, A. [Graduate Institute of Ferrous Technology, POSTECH, Pohang 790-784 (Korea, Republic of); Kim, Nack J., E-mail: njkim@postech.ac.kr [Graduate Institute of Ferrous Technology, POSTECH, Pohang 790-784 (Korea, Republic of)

    2015-09-17

    The effect of wire drawing on the microstructural evolution and deformation behavior of Fe–Mn–Al–C twinning-induced plasticity (TWIP) steel has been investigated. The inhomogeneities of the stress state, texture, microstructure, and mechanical properties were clarified over the cross section of drawn wire with the aid of numerical simulation, Schmid factor analysis, and electron backscatter diffraction (EBSD) techniques. The analysis of texture in drawn wire shows that a mixture of <111> and <100> fiber texture was developed with strain; however, the distribution of <111> and <100> fibers was inhomogeneous along the radial direction of wire due to uneven strain distribution and different stress state along the radial direction. It has also been shown that the morphology, volume fraction, and variant system of twins as well as twinning rate were dependent on the imposed stress state. The surface area was subjected to larger strain and more complex stress state involving compression, shear, and tension than the center area, resulting in a larger twin volume fraction and more twin variants in the former than in the latter at all the strain levels. While the surface area was saturated with twins at an early stage of drawing, the center area was not saturated with twins even at fracture, implying that the fracture of wire were initiated at the surface area because of the exhaustion of ductility due to twinning. Based on these results, it is suggested that imposing a uniform strain distribution along the radial direction of wire by the control of processing conditions such as die angle and amount of reduction per pass is necessary to increase the drawing limit of TWIP steel.

  1. Evidence that Cache Valley virus induces congenital malformations in sheep.

    Science.gov (United States)

    Chung, S I; Livingston, C W; Edwards, J F; Crandell, R W; Shope, R E; Shelton, M J; Collisson, E W

    1990-02-01

    An outbreak of congenital abnormalities occurred in sheep at San Angelo, Texas, between December 1986 and February 1987. Of 360 lambs born, 19.2% had arthrogryposis or other musculo-skeletal problems and hydranencephaly (AGH), and the total neonatal loss was 25.6%. In 1987, all ewes that were tested with AGH lambs had antibody to Cache Valley virus (CVV), whereas 62% of the ewes with normal lambs had CVV-specific antibody. Pre-colostral serum samples from AGH lambs had neutralizing antibody to CVV. An increase in prevalence of CVV-specific antibody, from 5% during the spring of 1986 to 63.4% during the winter of 1987, occurred during a time that included the gestation of these affected lambs, as well as a period of increased rainfall. The isolation of a CVV-related strain from a sentinel sheep in October 1987 confirmed the continued presence of this virus in the pasture where this outbreak occurred and provided a recent field strain for future studies.

  2. Cartilage regeneration by chondrogenic induced adult stem cells in osteoarthritic sheep model.

    Directory of Open Access Journals (Sweden)

    Chinedu C Ude

    Full Text Available OBJECTIVES: In this study, Adipose stem cells (ADSC and bone marrow stem cells (BMSC, multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model. METHODS: Osteoarthritis was induced at the right knee of sheep by complete resection of the anterior cruciate ligament and medial meniscus following a 3-weeks exercise regimen. Stem cells from experimental sheep were culture expanded and induced to chondrogenic lineage. Test sheep received a single dose of 2 × 10(7 autologous PKH26-labelled, chondrogenically induced ADSCs or BMSCs as 5 mls injection, while controls received 5 mls culture medium. RESULTS: The proliferation rate of ADSCs 34.4 ± 1.6 hr was significantly higher than that of the BMSCs 48.8 ± 5.3 hr (P = 0.008. Chondrogenic induced BMSCs had significantly higher expressions of chondrogenic specific genes (Collagen II, SOX9 and Aggrecan compared to chondrogenic ADSCs (P = 0.031, 0.010 and 0.013. Grossly, the treated knee joints showed regenerated de novo cartilages within 6 weeks post-treatment. On the International Cartilage Repair Society grade scores, chondrogenically induced ADSCs and BMSCs groups had significantly lower scores than controls (P = 0.0001 and 0.0001. Fluorescence of the tracking dye (PKH26 in the injected cells showed that they had populated the damaged area of cartilage. Histological staining revealed loosely packed matrixes of de novo cartilages and immunostaining demonstrated the presence of cartilage specific proteins, Collagen II and SOX9. CONCLUSION: Autologous chondrogenically induced ADSCs and BMSCs could be promising cell sources for cartilage regeneration in osteoarthritis.

  3. Effects of Aluminum Addition on Tensile and Cup Forming Properties of Three Twinning Induced Plasticity Steels

    Science.gov (United States)

    Hong, Seokmin; Shin, Sang Yong; Kim, Hyoung Seop; Lee, Sunghak; Kim, Sung-Kyu; Chin, Kwang-Geun; Kim, Nack J.

    2012-06-01

    In the present study, a high Mn twinning induced plasticity (TWIP) steel and two Al-added TWIP steels were fabricated, and their microstructures, tensile properties, and cup formability were analyzed to investigate the effects of Al addition on deformation mechanisms in tensile and cup forming tests. In the high Mn steel, the twin formation was activated to increase the strain hardening rate and ultimate tensile strength, which needed the high punch load during the cup forming test. In the Al-added TWIP steels, the twin formation was reduced, while the slip activation increased, thereby leading to the decrease in strain hardening rate and ultimate tensile strength. As twins and slips were homogeneously formed during the tensile or cup forming test, the punch load required for the cup forming and residual stresses were relatively low, and the tensile ductility was sufficiently high even after the cup forming test. This indicated that making use of twins and slips simultaneously in TWIP steels by the Al addition was an effective way to improve overall properties including cup formability.

  4. Pigmented spots in the wool-bearing skin on white merino sheep induced by ultraviolet light.

    Science.gov (United States)

    Forrest, J W; Fleet, M R

    1986-01-01

    Black-grey pigmented skin spots, some of which contained pigmented wool fibres, were observed in a flock of 8.5-year-old white Merino ewes. The spots were concentrated along the backline and increased in number following shearing, suggesting exposure to sunlight to be of importance in the development of these non-congenital pigmented skin spots in genetically white Merino sheep. To test the effect of ultraviolet light, white Merino sheep, ranging in age from 3 to 8 years, had a closely clipped midside area of wool-bearing skin irradiated on each of 28 consecutive days. Pigmented skin spots developed in 6 of the 16 white Merino sheep irradiated. Spots first appeared after 10 days of irradiation, the number subsequently increasing with time, and two skin spots were found to contain sparse numbers of black-grey pigmented wool fibres. Histological examination showed both the naturally occurring and irradiation-induced pigmented skin spots resulted from an increase in both number and activity of melanocytes localized along the epidermal-dermal border of the epidermis. With time, the melanocytes were observed to have entered, to varying depths, the outer-root sheath of follicles still producing white wool fibres. These ultraviolet-light-induced changes to epidermal melanocytes in white Merino sheep presumably occur due to alterations within the local tissue environment in which the melanocytes lie.

  5. Suppression of dislocations at high strain rate deformation in a twinning-induced plasticity steel

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Z.Y. [Shenzhen Institute of Research and Innovation, The University of Hong Kong, Shenzhen (China); Department of Mechanical Engineering, The University of Hong Kong, Hong Kong (China); Huang, W., E-mail: whuang@szu.edu.cn [Department of Civil Engineering, Shenzhen University, Shenzhen (China); Huang, M.X., E-mail: mxhuang@hku.hk [Shenzhen Institute of Research and Innovation, The University of Hong Kong, Shenzhen (China); Department of Mechanical Engineering, The University of Hong Kong, Hong Kong (China)

    2015-03-25

    The increase of strain rate generally enhances dislocation evolution in face-centred cubic (FCC) metals. However, by synchrotron X-ray diffraction experiments, the present work demonstrates for the first time that a higher strain rate leads to a lower dislocation density in a twinning-induced plasticity steel with an FCC structure. This unexpected suppression of dislocation evolution has been attributed to the temperature increase due to dissipative heating at high strain rate deformation.

  6. Model for twin electromagnons and magnetically induced oscillatory polarization in multiferroic RMnO3

    Science.gov (United States)

    de Sousa, Rogério; Stenberg, Markku

    2010-03-01

    We propose a model [1] for the pair of electromagnon excitations observed in the class of multiferroic materials RMnO3 (R is a rare-earth ion). The model is based on a harmonic cycloid ground state interacting with a zone-edge magnon and its twin excitation separated in momentum space by two times the cycloid wave vector. The pair of electromagnons is activated by cross coupling between magnetostriction and spin-orbit interactions. Remarkably, the spectral weight of the twin electromagnon is directly related to the presence of a magnetically induced oscillatory polarization in the ground state. This leads to the surprising prediction that TbMnO3 has an oscillatory polarization with amplitude 50 times larger than its uniform polarization. [4pt] [1] M.P.V. Stenberg and R. de Sousa, Phys. Rev. B 80, 094419 (2009) (Editors' suggestion).

  7. Bovine leukemia virus high tax molecular clone experimentally induces leukemia/lymphoma in sheep.

    Science.gov (United States)

    Okada, Kosuke; Nakae, Norihiro; Kuramochi, Konomi; Yin, Shan-ai; Ikeda, Manabu; Takami, Shigeaki; Hirata, Tou-ichi; Goryo, Masanobu; Numakunai, Shigeru; Takeshima, Shin-nosuke; Takahashi, Masahiko; Tajima, Shigeru; Konnai, Satoru; Onuma, Misao; Aida, Yoko

    2005-12-01

    Sheep were inoculated with high tax coded pBLV-IF (H group, Nos.1-5) of bovine leukemia virus (BLV), wild tax coded pBLV-IF (W group, Nos. 6-11), or control plasmid (C group, Nos. 12-14). During the observation period (4 to 46 months), 5 of 5 cases in H group and 3 of 6 cases (Nos. 6, 7, 9) in W group became positive for gp 51. Only 1 case in H group became leukemic, and one case each of H and W groups developed lymphoma. In No. 3, lesions were found in multiple organs including the lymph nodes, gastrointestinal tract following abomasum, and heart. In No. 6, lesions of lymphoma were found only in the jejunum and heart. Morphologically, small to middle-sized lymphocytic neoplastic (NP) cells were found in both cases, but lymphoblastic NP cells were found only in No. 3. By immunohistochemical examination, the phenotypes of NP cells were determined as CD1-, CD4-, CD5- -, CD8alpha-, sIgM+, lambda light chain+, B-B4+, MHC class II+ in both case. The results of this study indicate that inoculation of pBLV-IF can induce lymphocytic and lymphoblastic leukemia/lymphoma in sheep. Additionally, it is suggested that the expression rate of tax gene is not associated with the development of leukemia/lymphoma in sheep experimentally inoculated with pBLV-IF.

  8. Blood-brain barrier permeability during dopamine-induced hypertension in fetal sheep.

    Science.gov (United States)

    Harris, A P; Robinson, R; Koehler, R C; Traystman, R J; Gleason, C A

    2001-07-01

    Dopamine is often used as a pressor agent in sick newborn infants, but an increase in arterial blood pressure could disrupt the blood-brain barrier (BBB), especially in the preterm newborn. Using time-dated pregnant sheep, we tested the hypothesis that dopamine-induced hypertension increases fetal BBB permeability and cerebral water content. Barrier permeability was assessed in nine brain regions, including cerebral cortex, caudate, thalamus, brain stem, cerebellum, and spinal cord, by intravenous injection of the small tracer molecule [(14)C]aminoisobutyric acid at 10 min after the start of dopamine or saline infusion. We studied 23 chronically catheterized fetal sheep at 0.6 (93 days, n = 10) and 0.9 (132 days, n = 13) gestation. Intravenous infusion of dopamine increased mean arterial pressure from 38 +/- 3 to 53 +/- 5 mmHg in 93-day fetuses and from 55 +/- 5 to 77 +/- 8 mmHg in 132-day fetuses without a decrease in arterial O(2) content. These 40% increases in arterial pressure are close to the maximum hypertension reported for physiological stresses at these ages in fetal sheep. No significant increases in the brain transfer coefficient of aminoisobutyric acid were detected in any brain region in dopamine-treated fetuses compared with saline controls at 0.6 or 0.9 gestation. There was also no significant increase in cortical water content with dopamine infusion at either age. We conclude that a 40% increase in mean arterial pressure during dopamine infusion in normoxic fetal sheep does not produce substantial BBB disruption or cerebral edema even as early as 0.6 gestation.

  9. An 11-year follow-up study of neonatal-onset, bath-induced alternating hemiplegia of childhood in twins.

    Science.gov (United States)

    Incorpora, Gemma; Pavone, Piero; Polizzi, Agata; Cocuzza, Mariadonatella; Privitera, Michael; Pavone, Lorenzo; Ruggieri, Martino

    2012-05-01

    The authors previously reported on the initial manifestations in a set of female twins, who presented soon after birth with bath-induced paroxysmal events each time they were immersed in a warm water bath. These episodes progressively ceased by the age of 36 months, replaced by paroxysmal episodes of alternating hemiplegia unrelated to water immersion. By age 4 years, the twins developed the classic features of alternating hemiplegia of childhood. Clinical outcomes at the age of 11 years are now reported. Standard and video-electroencephalograms showed a large, slow background activity followed by lower amplitude waves without focal abnormalities or other abnormal findings. This represents the first report on (a) alternating hemiplegia of childhood started with bath-induced paroxysmal episodes; (b) this condition in monozygotic twins; and (c) an 11-year follow-up study in which the twins continue to experience episodes of alternating hemiplegia in the setting of baseline cognitive impairment without epileptic episodes.

  10. In-situ strain localization analysis in low density transformation-twinning induced plasticity steel using digital image correlation

    Science.gov (United States)

    Eskandari, M.; Yadegari-Dehnavi, M. R.; Zarei-Hanzaki, A.; Mohtadi-Bonab, M. A.; Basu, R.; Szpunar, J. A.

    2015-04-01

    The effect of deformation temperature on the strain localization has been evaluated by an adapted digital image correlation (DIC) technique during tensile deformation. The progress of strain localization was traced by the corresponding strain maps. The electron backscatter diffraction analysis and tint etching technique were utilized to determine the impact of martensitic transformation and deformation twinning on the strain localization in both elastic and plastic regimes. In elastic regime the narrow strain bands which are aligned perpendicular to the tension direction were observed in temperature range of 25 to 180 °C due to the stress-assisted epsilon martensite. The strain bands were disappeared by increasing the temperature to 300 °C and reappeared at 400 °C due to the stress-assisted deformation twinning. In plastic regime strain localization continued at 25 °C and 180 °C due to the strain-induced alfa-martensite and deformation twinning, respectively. The intensity of plastic strain localization was increased by increasing the strain due to the enhancement of martensite and twin volume fraction. The plastic strain showed more homogeneity at 300 °C due to the lack of both strain-induced martensite and deformation twinning. Effect of deformation mechanism by changing temperature on strain localization is investigated by digital image correlation. EBSD technique is served to validate deformation mechanism as well as microstructural evolution. Strain induced martensite as well as deformation twinning is activated in the present steel affecting strain localization.

  11. A computed tomographic scan assessment of endotracheal suctioning-induced bronchoconstriction in ventilated sheep.

    Science.gov (United States)

    Lu, Q; Capderou, A; Cluzel, P; Mourgeon, E; Abdennour, L; Law-Koune, J D; Straus, C; Grenier, P; Zelter, M; Rouby, J J

    2000-11-01

    This study was directed at assessing changes in bronchial cross-sectional surface areas (BCSA) and in respiratory resistance induced by endotracheal suctioning in nine anesthetized sheep. Cardiorespiratory parameters (Swan-Ganz catheter), respiratory resistance (inspiratory occlusion technique), BCSA, and lung aeration (computed tomography) were studied at baseline, during endotracheal suctioning, and after 20 consecutive hyperinflations. Measurements performed initially at an inspired oxygen fraction (FI(O(2))) of 0.3 were repeated at an FI(O(2)) of 1.0. At an FI(O(2)) of 0.3, endotracheal suctioning resulted in atelectasis, a reduction in BCSA of 29 +/- 23% (mean +/- SD), a decrease in arterial oxygen saturation from 95 +/- 3% to 87 +/- 12% (p = 0.02), an increase in venous admixture from 19 +/- 10% to 31 +/- 19% (p = 0. 006), and an increase in lung tissue resistance (DR(rs)) (p = 0. 0003). At an FI(O(2)) of 1.0, despite an extension of atelectasis and an increase in pulmonary shunt from 19 +/- 5% to 36 +/- 2% (p sheep, the endotracheal suctioning-induced reduction of BCSA was entirely prevented. These data suggest that the endotracheal suctioning-induced decrease in BCSA is related to atelectasis and bronchoconstriction. Both effects can be reversed by hyperoxygenation maneuver before suctioning in combination with recruitment maneuver after suctioning.

  12. Reprogramming of sheep fibroblasts into pluripotency under a drug-inducible expression of mouse-derived defined factors.

    Directory of Open Access Journals (Sweden)

    Yang Li

    Full Text Available Animal embryonic stem cells (ESCs provide powerful tool for studies of early embryonic development, gene targeting, cloning, and regenerative medicine. However, the majority of attempts to establish ESC lines from large animals, especially ungulate mammals have failed. Recently, another type of pluripotent stem cells, known as induced pluripotent stem cells (iPSCs, have been successfully generated from mouse, human, monkey, rat and pig. In this study we show sheep fibroblasts can be reprogrammed to pluripotency by defined factors using a drug-inducible system. Sheep iPSCs derived in this fashion have a normal karyotype, exhibit morphological features similar to those of human ESCs and express AP, Oct4, Sox2, Nanog and the cell surface marker SSEA-4. Pluripotency of these cells was further confirmed by embryoid body (EB and teratoma formation assays which generated derivatives of all three germ layers. Our results also show that the substitution of knockout serum replacement (KSR with fetal bovine serum in culture improves the reprogramming efficiency of sheep iPSCs. Generation of sheep iPSCs places sheep on the front lines of large animal preclinical trials and experiments involving modification of animal genomes.

  13. Fasciola hepatica induces eosinophil apoptosis in the migratory and biliary stages of infection in sheep.

    Science.gov (United States)

    Escamilla, A; Bautista, M J; Zafra, R; Pacheco, I L; Ruiz, M T; Martínez-Cruz, S; Méndez, A; Martínez-Moreno, A; Molina-Hernández, V; Pérez, J

    2016-01-30

    The aim of the present work was to evaluate the number of apoptotic eosinophils in the livers of sheep experimentally infected with Fasciola hepatica during the migratory and biliary stages of infection. Four groups (n=5) of sheep were used; groups 1-3 were orally infected with 200 metacercariae (mc) and sacrificed at 8 and 28 days post-infection (dpi), and 17 weeks post-infection (wpi), respectively. Group 4 was used as an uninfected control. Apoptosis was detected using immunohistochemistry with a polyclonal antibody against anti-active caspase-3, and transmission electron microscopy (TEM). Eosinophils were identified using the Hansel stain in serial sections for caspase-3, and by ultrastructural features using TEM. At 8 and 28 dpi, numerous caspase-3(+) eosinophils were mainly found at the periphery of acute hepatic necrotic foci. The percentage of caspase -3(+) apoptotic eosinophils in the periphery of necrotic foci was high (46.1-53.9) at 8 and 28 dpi, respectively, and decreased in granulomas found at 28 dpi (6%). Transmission electron microscopy confirmed the presence of apoptotic eosinophils in hepatic lesions at 8 and 28 dpi. At 17 wpi, apoptotic eosinophils were detected in the infiltrate surrounding some enlarged bile ducts containing adult flukes. This is the first report of apoptosis induced by F. hepatica in sheep and the first study reporting apoptosis in eosinophils in hepatic inflammatory infiltrates in vivo. The high number of apoptotic eosinophils in acute necrotic tracts during the migratory and biliary stages of infection suggests that eosinophil apoptosis may play a role in F. hepatica survival during different stages of infection.

  14. The similiarity of facial expressions in response to emotion-inducing films in reared-apart twins.

    Science.gov (United States)

    Kendler, K S; Halberstadt, L J; Butera, F; Myers, J; Bouchard, T; Ekman, P

    2008-10-01

    While the role of genetic factors in self-report measures of emotion has been frequently studied, we know little about the degree to which genetic factors influence emotional facial expressions. Twenty-eight pairs of monozygotic (MZ) and dizygotic (DZ) twins from the Minnesota Study of Twins Reared Apart were shown three emotion-inducing films and their facial responses recorded. These recordings were blindly scored by trained raters. Ranked correlations between twins were calculated controlling for age and sex. Twin pairs were significantly correlated for facial expressions of general positive emotions, happiness, surprise and anger, but not for general negative emotions, sadness, or disgust or average emotional intensity. MZ pairs (n=18) were more correlated than DZ pairs (n=10) for most but not all emotional expressions. Since these twin pairs had minimal contact with each other prior to testing, these results support significant genetic effects on the facial display of at least some human emotions in response to standardized stimuli. The small sample size resulted in estimated twin correlations with very wide confidence intervals.

  15. Glucocorticoid induced osteopenia in cancellous bone of sheep: validation of large animal model for spine fusion and biomaterial research

    DEFF Research Database (Denmark)

    Ding, Ming; Cheng, Liming; Bollen, Peter

    2010-01-01

    STUDY DESIGN: Glucocorticoid with low calcium and phosphorus intake induces osteopenia in cancellous bone of sheep. OBJECTIVE: To validate a large animal model for spine fusion and biomaterial research. SUMMARY OF BACKGROUND DATA: A variety of ovariectomized animals has been used to study osteopo...

  16. Some Aspects of High Manganese Twinning-Induced Plasticity (TWIP) Steel, A Review

    Institute of Scientific and Technical Information of China (English)

    Liqing CHEN; Yang ZHAO; Xiaomei QIN

    2013-01-01

    High manganese twinning-induced plasticity (TWIP) steel is a new kind of structural material and possesses both high strength and superior plasticity and can meet the weight-lightening requirement for manufacturing vehicle body.The excellent formability of the TWIP steel comes from the extraordinary strain hardening effect during plastic deformation.The reduction of specific weight by aluminum alloying and strain hardening effect can lead to an effective weight reduction of the steel components,and provide a better choice for materials in vehicle body design.The TWIP effect in high Mn steels is generally associated with the successive workhardening generated by twins and influenced by some factors,such as Mn content,AI addition revealed by stacking fault energy (SFE),grain size,deformation temperature and strain rate.The present review introduces some aspects of the TWIP steels relating to their physical metallurgy,influencing factors associated with their deformation mechanisms,and a prospect for the future investigation is also described.Moreover,as a potential candidate for replacing Ni-Cr austenitic stainless steel,researches on the oxidation behavior and corrosion resistance of Fe-Mn-AI-C system steels are also reviewed.

  17. Twinned-domain-induced magnonic modes in epitaxial LSMO/STO films

    Science.gov (United States)

    Wahlström, Erik; Macià, Ferran; Boschker, Jos E.; Monsen, Åsmund; Nordblad, Per; Mathieu, Roland; Kent, Andrew D.; Tybell, Thomas

    2017-06-01

    The use of periodic magnetic structures to control the magneto-dynamic properties of materials—magnonics—is a rapidly developing field. In the last decade, a number of studies have shown that metallic films can be patterned or combined in patterns that give rise to well-defined magnetization modes, which are formed due to band folding or band gap effects. To explore and utilize these effects in a wide frequency range, it is necessary to pattern samples at the sub-micrometer scale. However, it is still a major challenge to produce low-loss magnonic structures with periodicities at such length scales. Here, we show that for a prototypical perovskite, {{La}}0.7 {{Sr}}0.3 MnO3, the twinned structural order can be used to induce a magnetic modulation with a period smaller than 100 nm, demonstrating a bottom-up approach for magnonic crystal growth.

  18. The "Ram Effect": A "Non-Classical" Mechanism for Inducing LH Surges in Sheep.

    Science.gov (United States)

    Fabre-Nys, Claude; Chanvallon, Audrey; Dupont, Joëlle; Lardic, Lionel; Lomet, Didier; Martinet, Stéphanie; Scaramuzzi, Rex J

    2016-01-01

    During spring sheep do not normally ovulate but exposure to a ram can induce ovulation. In some ewes an LH surge is induced immediately after exposure to a ram thus raising questions about the control of this precocious LH surge. Our first aim was to determine the plasma concentrations of oestradiol (E2) E2 in anoestrous ewes before and after the "ram effect" in ewes that had a "precocious" LH surge (starting within 6 hours), a "normal" surge (between 6 and 28h) and "late» surge (not detected by 56h). In another experiment we tested if a small increase in circulating E2 could induce an LH surge in anoestrus ewes. The concentration of E2 significantly was not different at the time of ram introduction among ewes with the three types of LH surge. "Precocious" LH surges were not preceded by a large increase in E2 unlike "normal" surges and small elevations of circulating E2 alone were unable to induce LH surges. These results show that the "precocious" LH surge was not the result of E2 positive feedback. Our second aim was to test if noradrenaline (NA) is involved in the LH response to the "ram effect". Using double labelling for Fos and tyrosine hydroxylase (TH) we showed that exposure of anoestrous ewes to a ram induced a higher density of cells positive for both in the A1 nucleus and the Locus Coeruleus complex compared to unstimulated controls. Finally, the administration by retrodialysis into the preoptic area, of NA increased the proportion of ewes with an LH response to ram odor whereas treatment with the α1 antagonist Prazosin decreased the LH pulse frequency and amplitude induced by a sexually active ram. Collectively these results suggest that in anoestrous ewes NA is involved in ram-induced LH secretion as observed in other induced ovulators.

  19. Vaccination with cathepsin L proteinases and with leucine aminopeptidase induces high levels of protection against fascioliasis in sheep.

    Science.gov (United States)

    Piacenza, L; Acosta, D; Basmadjian, I; Dalton, J P; Carmona, C

    1999-04-01

    The potential of different parasite proteinases for use as vaccine candidates against fascioliasis in sheep was studied by vaccinating animals with the cathepsin L proteinases CL1 and CL2 and with leucine aminopeptidase (LAP) purified from adult flukes. In the first trial, sheep were immunized with CL1 or CL2 and the mean protection levels obtained were 33 and 34%, respectively. Furthermore, a significant reduction in egg output was observed in sheep vaccinated either with CL1 (71%) or with CL2 (81%). The second trial was performed to determine the protective potential of the two cathepsin L proteinases assayed together, as well as in combination with LAP, and of LAP alone. The combination of CL1 and CL2 induced higher levels of protection (60%) than those produced when these enzymes were administered separately. Those sheep that received the cocktail vaccine including CL1, CL2, and LAP were significantly protected (78%) against metacercarial challenge, but vaccination with LAP alone elicited the highest level of protection (89%). All vaccine preparations induced high immunoglobulin G titers which were boosted after the challenge infection, but no correlations between antibody titers and worm burdens were found. However, the sera of those animals vaccinated with LAP contained LAP-neutralizing antibodies. Reduced liver damage, as assessed by the level of the liver enzyme gamma-glutamyl transferase, was observed in the groups vaccinated with CL1, CL2, and LAP or with LAP alone.

  20. Differentially Expressed microRNAs Screening Between Ovaries of Sheep Producing Single Lamb and Twins%单双羔绵羊卵巢组织差异表达microRNAs筛选

    Institute of Scientific and Technical Information of China (English)

    祁云霞; 刘晓芳; 张萍; 何小龙; 邢玉梅; 达赖; 特日格勒; 刘永斌; 荣威恒

    2015-01-01

    因AHR参与生殖过程的调控。【结论】成功构建了绵羊卵巢miRNAs表达谱,获得产单羔母羊和产双羔母羊卵巢组织差异表达miRNAs,这些miRNAs可能与绵羊卵泡发育和产羔数多少有关。%[Objective]This study was conducted to get a comprehensive understanding of miRNAs expression in sheep ovary, and to analyze their expression differences between sheep producing single lamb and twins, thus providing a basis for exploring the role of miRNAs in the regulation of fertility. [Method] Multi-species miRNA microarray was used to profile ovarian miRNAs expression in sheep. Firstly, single-lamb-producing and twin-producing ewes were selected. Ovaries were collected after estrus for total RNA extraction, and small RNA fragments were isolated and hybridized with miRNA microarray. Then data analysis was performed to obtain sheep ovarian miRNAs profile. Differentially expressed microRNAs were selected by bioinformatics software with the standard of q-value ≤ 5%and Fold Change ≥2 or ≤0.5, and q-PCR technique was employed to testify the microarray results. Two different methods, microT and miRDB, were used, respectively, and then data were merged and to predict target genes. Finally, online software was used to perform GO function annotation for target genes.[Result]Among all the detected miRNAs, a total of 5448 miRNAs were detected in sheep ovaries, of which 22 were specifically expressed in single-lamb-producing group, while 15 were in twin-producing group; For the miRNAs reported in sheep, expression differences were compared between two groups, and obtained 11 differentially expressed miRNAs, with 7 down-regulated and 4 up-regulated. Tow miRNAs were randomly selected to perform q-PCR validation, and the results were consistent with the microarray results, illustrating that the microarray results were accurate and credible. Target genes were obtained for 7 miRNAs:oar-miR-370-5p, oar-miR-376b-5p, oar-miR-381-5p, oar-miR-412-5p

  1. Maternal diet during pregnancy induces gene expression and DNA methylation changes in fetal tissues in sheep

    Directory of Open Access Journals (Sweden)

    Xianyong eLan

    2013-04-01

    Full Text Available Studies in rats and mice have established that maternal nutrition induces epigenetic modifications, sometimes permanently, that alter gene expression in the fetus, which in turn leads to phenotypic changes. However, limited data is available on the influence of maternal diet on epigenetic modifications and gene expression in sheep. Therefore, the objectives of this study were to investigate the impact of different maternal dietary energy sources on the expression of imprinted genes in fetuses in sheep. Ewes were naturally bred to a single sire and from d 67 ± 3 of gestation until necropsy (d 130 ± 1, they were fed one of three diets of alfalfa haylage (HY; fiber, corn (CN; starch, or dried corn distiller’s grains (DG; fiber plus protein plus fat. A total of 26 fetuses were removed from the dams and longissimus dorsi, semitendinosus, perirenal adipose depot, and subcutaneous adipose depot tissues were collected for expression and DNA methylation analyses. Expression analysis of nine imprinted genes and three DNA methylatransferase (DNMTs genes showed significant effects of the different maternal diets on the expression of these genes. The methylation levels of CpG islands of both IGF2R and H19 were higher in HY and DG than CN fetuses in both males and females. This result is consistent with the low amino acid content of the CN diet, a source of methyl group donors, compared to HY and DG diets. Thus, results of this study provide evidence of association between maternal nutrition during pregnancy and transcriptomic and epigenomic alterations of imprinted genes and DNMTs in the fetal tissues.

  2. Autoimmune/autoinflammatory syndrome induced by adjuvants (ASIA syndrome) in commercial sheep.

    Science.gov (United States)

    Luján, Lluís; Pérez, Marta; Salazar, Eider; Álvarez, Neila; Gimeno, Marina; Pinczowski, Pedro; Irusta, Silvia; Santamaría, Jesús; Insausti, Nerea; Cortés, Yerzol; Figueras, Luis; Cuartielles, Isabel; Vila, Miguel; Fantova, Enrique; Chapullé, José Luis Gracia

    2013-07-01

    We describe a form of the autoimmune/autoinflammatory syndrome induced by adjuvants (ASIA syndrome) in commercial sheep, linked to the repetitive inoculation of aluminum-containing adjuvants through vaccination. The syndrome shows an acute phase that affects less than 0.5% of animals in a given herd, it appears 2-6 days after an adjuvant-containing inoculation and it is characterized by an acute neurological episode with low response to external stimuli and acute meningoencephalitis, most animals apparently recovering afterward. The chronic phase is seen in a higher proportion of flocks, it can follow the acute phase, and it is triggered by external stimuli, mostly low temperatures. The chronic phase begins with an excitatory phase, followed by weakness, extreme cachexia, tetraplegia and death. Gross lesions are related to a cachectic process with muscular atrophy, and microscopic lesions are mostly linked to a neurodegenerative process in both dorsal and ventral column of the gray matter of the spinal cord. Experimental reproduction of ovine ASIA in a small group of repeatedly vaccinated animals was successful. Detection of Al(III) in tissues indicated the presence of aluminum in the nervous tissue of experimental animals. The present report is the first description of a new sheep syndrome (ovine ASIA syndrome) linked to multiple, repetitive vaccination and that can have devastating consequences as it happened after the compulsory vaccination against bluetongue in 2008. The ovine ASIA syndrome can be used as a model of other similar diseases affecting both human and animals. A major research effort is needed in order to understand its complex pathogenesis.

  3. Conjoined Twins

    Science.gov (United States)

    ... sites of conjoined twins. Abdomen. Omphalopagus (om-fuh-LOP-uh-gus) twins are joined near the bellybutton. ... brain tissue. Head and chest. Cephalopagus (sef-uh-LOP-uh-gus) twins are joined at the face ...

  4. Marked differences in drug-induced methemoglobinemia in sheep are not due to RBC glucose-6-phosphate dehydrogenase, reduced glutathione, or methemoglobin reductase activity

    Energy Technology Data Exchange (ETDEWEB)

    Martin, D.G.; Guertler, A.T.; Lagutchik, M.S.; Woodard, C.L.; Leonard, D.A.

    1993-05-13

    Benzocaine is a commonly used topical anesthetic that is structurally similar to current candidates for cyanide prophylaxis. Benzocaine induces profound methemoglobinemia in some sheep but not others. After topical benzocaine administration certain sheep respond to form MHb (elevated MHb 16-50% after a 56-280 mg dose, a 2-10 second spray with benzocine), while other phenotypically similar sheep fail to significantly form MHb (less than a 2% increase from baseline). Deficiencies in Glucose-6-phosphate dehydrogenase (G-6-PD), reduced glutathione (GSH), and MHb reductase increase the susceptibility to methemoglobinemia in man and animals. Sheep are used as a model for G-6-PD deficiency in man, and differences in this enzyme level could cause the variable response seen in these sheep. Similarly, differences in GSH and MHb reductase could be responsible for the observed differences in MHb formation.

  5. Ghrelin enhances glucose-induced insulin secretion in scheduled meal-fed sheep.

    Science.gov (United States)

    Takahashi, H; Kurose, Y; Kobayashi, S; Sugino, T; Kojima, M; Kangawa, K; Hasegawa, Y; Terashima, Y

    2006-04-01

    The purpose of this study was to investigate the effects of physiologic levels of ghrelin on insulin secretion and insulin sensitivity (glucose disposal) in scheduled fed-sheep, using the hyperglycemic clamp and hyperinsulinemic euglycemic clamp respectively. Twelve castrated Suffolk rams (69.8 +/- 0.6 kg) were conditioned to be fed alfalfa hay cubes (2% of body weight) once a day. Three hours after the feeding, synthetic ovine ghrelin was intravenously administered to the animals at a rate of 0.025 and 0.05 mug/kg body weight (BW) per min for 3 h. Concomitantly, the hyperglycemic clamp or the hyperinsulinemic euglycemic clamp was carried out. In the hyperglycemic clamp, a target glucose concentration was clamped at 100 mg/100 ml above the initial level. In the hyperinsulinemic euglycemic clamp, insulin was intravenously administered to the animals for 3 h at a rate of 2 mU/kg BW per min. Basal glucose concentrations (44+/- 1 mg/dl) were maintained by variably infusing 100 mg/dl glucose solution. In both clamps, plasma ghrelin concentrations were dose-dependently elevated and maintained at a constant level within the physiologic range. Ghrelin infusions induced a significant (ANOVA; P ghrelin-infused animals. In the hyperinsulinemic euglycemic clamp, glucose infusion rate, an index of insulin sensitivity, was not affected by ghrelin infusion. In conclusion, the present study has demonstrated for the first time that ghrelin enhances glucose-induced insulin secretion in the ruminant animal.

  6. Vertebral plate regeneration induced by radiation-sterilized allogeneic bone sheets in sheep

    Institute of Scientific and Technical Information of China (English)

    TANG Xin; SUN Shi-quan; YU Cong-nian; YANG Shu-hua; XU Wei-hua; LI Jin; YANG Cao; YE Zhe-wei; FU De-hao; LI Kun; LI Bao-xing

    2007-01-01

    Objective:To evaluate the effects and mechanism of radiation-sterilized allogeneic bone sheets in inducing vertebral plate regeneration after laminectomy in sheep. Methods:Twelve adult male sheep (aged 1.5 years and weighing 27 kg on average ) provided by China Institute for Radiation Protection underwent L3-4 and L4-5 laminectomy.Then they were randomly divided into two groups:Group A (n =6) and Group B (n =6).The operated sites of L4-5 in Group A and L3-4 in Group B were covered by "H-shaped" freeze-drying and radiationsterilized allogeneic bone sheets ( the experimental segments),while the operated sites of L3-4 in Group A and L4-5 in Group B were uncovered as the self controls ( the control segments ). The regeneration process of the vertebral plate and the adhesion degree of the dura were observed at 4,8,12,16,20 and 24 weeks after operation.Xray and CT scan were performed in both segments of L3-4 and L4-5 at 4 and 24 weeks after operation. Results:In the experimental segments,the bone sheets were located in the anatomical site of vertebral plate,and no lumbar spinal stenosis or compression of the dura was observed.The bone sheets were absorbed gradually and fused well with the regenerated vertebral plate.While in the control segments,the regeneration of vertebral plate was not completed yet,the scar was inserted into the spinal canal,compressing the dura and the spinal cord,and the epidural area almost disappeared. Compared with the control segments, the dura adhesion degree in the experimental regenerated segments was much milder (P <0.01 ),the internal volume of the vertebral canal had no obvious change and the shape of the dura sack remained well without obvious compression. Conclusions:Freeze-drying and radiation-sterilized allogeneic bone sheets are ideal materials for extradural laminoplasty due to their good biocompatibility,biomechanical characteristics and osteogenic ability.They can effectively reduce formation of post-laminectomy scars

  7. Dependence of stress-induced omega transition and mechanical twinning on phase stability in metastable β Ti–V alloys

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.L.; Li, L.; Mei, W.; Wang, W.L.; Sun, J., E-mail: jsun@sjtu.edu.cn

    2015-09-15

    Tensile properties and deformation microstructures of a series of binary β Ti–16–22V alloys have been investigated. The results show that the plastic deformation mode changes from the plate-like stress-induced ω phase transformation with a special habit plane of (− 5052){sub ω}//(3 − 3 − 2){sub β} to (332)<113> type deformation twinning with increasing the content of vanadium in the β Ti–16–22 wt.% V alloys. The plate-like stress-induced ω phase has a special orientation relationship with the β phase matrix, i.e., [110]{sub β}//[− 12 − 10]{sub ω}, (3 − 3 − 2){sub β}//(− 5052){sub ω} and (− 55 − 4){sub β}//(30 − 31){sub ω}. The alloys plastically deformed by stress-induced ω phase transformation exhibit relatively higher yield strength than those deformed via (332)<113> type deformation twinning. It can be concluded that the stability of β phase plays a significant role in plastic deformation mode, i.e., stress-induced ω phase transformation or (332)<113> type deformation twinning, which governs the mechanical property of the β Ti–16–22 wt.% V alloys. - Highlights: • Tensile properties and deformed microstructures of β Ti–16–22V alloys were studied. • Stress-induced ω phase transformation and (332)<113> twinning occur in the alloys. • Stability of β phase plays a significant role in plastic deformation mode. • Plastic deformation mode governs the mechanical property of the alloys.

  8. Susceptibility of Rocky Mountain bighorn sheep and domestic sheep to pneumonia induced by bighorn and domestic livestock strains of Pasteurella haemolytica.

    Science.gov (United States)

    Onderka, D K; Rawluk, S A; Wishart, W D

    1988-10-01

    Bighorn sheep were inoculated intratracheally with suspensions of nonhemolytic Pasteurella haemolytica biotype T (10(12) organisms) unique to wild bighorns, with beta-hemolytic P. haemolytica biotype T (10(12) organisms) isolated from clinically normal domestic sheep or intradermally with half a dose of a cattle vaccine containing P. haemolytica biotype A (10(5) organisms). The bighorn strain caused lobar necrotizing bronchopneumonia whereas both domestic livestock strains precipitated fatal septicemia and fibrinous bronchopneumonia. The serotypes given were T3, T4, T15 and A1 and these were recovered from lung lesions and other organs. In three trials, domestic sheep were inoculated intratracheally with suspensions of bighorn sheep pneumonic lungs, and two concentrations of the P. haemolytica bighorn strain (10(4) and 10(12) organisms). One of these sheep was inoculated intrabronchially. The domestic sheep experienced a transient fever and elevated white blood cell counts. After six days, none of the sheep had lung lesions and inoculated organisms could not be recovered. It is suggested that bighorn sheep are very susceptible to P. haemolytica from domestic livestock and should not be allowed in contact with sheep or cattle.

  9. Endotoxin induced chorioamnionitis prevents intestinal development during gestation in fetal sheep.

    Directory of Open Access Journals (Sweden)

    Tim G A M Wolfs

    Full Text Available Chorioamnionitis is the most significant source of prenatal inflammation and preterm delivery. Prematurity and prenatal inflammation are associated with compromised postnatal developmental outcomes, of the intestinal immune defence, gut barrier function and the vascular system. We developed a sheep model to study how the antenatal development of the gut was affected by gestation and/or by endotoxin induced chorioamnionitis.Chorioamnionitis was induced at different gestational ages (GA. Animals were sacrificed at low GA after 2d or 14d exposure to chorioamnionitis. Long term effects of 30d exposure to chorioamnionitis were studied in near term animals after induction of chorioamnionitis. The cellular distribution of tight junction protein ZO-1 was shown to be underdeveloped at low GA whereas endotoxin induced chorioamnionitis prevented the maturation of tight junctions during later gestation. Endotoxin induced chorioamnionitis did not induce an early (2d inflammatory response in the gut in preterm animals. However, 14d after endotoxin administration preterm animals had increased numbers of T-lymphocytes, myeloperoxidase-positive cells and gammadelta T-cells which lasted till 30d after induction of chorioamnionitis in then near term animals. At early GA, low intestinal TLR-4 and MD-2 mRNA levels were detected which were further down regulated during endotoxin-induced chorioamnionitis. Predisposition to organ injury by ischemia was assessed by the vascular function of third-generation mesenteric arteries. Endotoxin-exposed animals of low GA had increased contractile response to the thromboxane A2 mimetic U46619 and reduced endothelium-dependent relaxation in responses to acetylcholine. The administration of a nitric oxide (NO donor completely restored endothelial dysfunction suggesting reduced NO bioavailability which was not due to low expression of endothelial nitric oxide synthase.Our results indicate that the distribution of the tight

  10. Insufficient irrigation induces peri-implant bone resorption: an in vivo histologic analysis in sheep.

    Science.gov (United States)

    Trisi, Paolo; Berardini, Marco; Falco, Antonello; Podaliri Vulpiani, Michele; Perfetti, Giorgio

    2014-06-01

    To measure in vivo impact of dense bone overheating on implant osseointegration and peri-implant bone resorption comparing different bur irrigation methods vs. no irrigation. Twenty TI-bone implants were inserted in the inferior edge of mandibles of sheep. Different cooling procedures were used in each group: no irrigation (group A), only internal bur irrigation (group B), both internal and external irrigation (group C), and external irrigation (group D). The histomorphometric parameters calculated for each implant were as follows: %cortical bone-implant contact (%CBIC) and %cortical bone volume (%CBV). Friedman's test was applied to test the statistical differences. In group A, we found a huge resorption of cortical bone with %CBIC and %CBV values extremely low. Groups B and C showed mean %CBIC and %BV values higher than other groups The mean %CBV value was significantly different when comparing group B and group C vs. group A (P < 0.05). Significant differences in %CBIC were found also between group C and group A (P < 0.05). Thermal injury, due to insufficient irrigation, of hard bone caused massive resorption of the cortical bone and implant failure. Drilling procedures on hard bone need an adequate cooling supply because the bone matrix overheating may induce complete resorption of dense bone around implants. Internal-external irrigation and only internal irrigation showed to be more efficient than other types of cooling methods in preventing bone resorption around implants. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  11. Elucidating fish oil-induced milk fat depression in dairy sheep: Milk somatic cell transcriptome analysis

    Science.gov (United States)

    Suárez-Vega, Aroa; Toral, Pablo G.; Gutiérrez-Gil, Beatriz; Hervás, Gonzalo; Arranz, Juan José; Frutos, Pilar

    2017-01-01

    In this study, RNA sequencing was used to obtain a comprehensive profile of the transcriptomic changes occurring in the mammary gland of lactating sheep suffering from fish oil-induced milk fat depression (FO-MFD). The milk somatic cell transcriptome analysis of four control and four FO-MFD ewes generated an average of 42 million paired-end reads per sample. In both conditions, less than 220 genes constitute approximately 89% of the total counts. These genes, which are considered as core genes, were mainly involved in cytoplasmic ribosomal proteins and electron transport chain pathways. In total, 117 genes were upregulated, and 96 genes were downregulated in FO-MFD samples. Functional analysis of the latter indicated a downregulation of genes involved in the SREBP signaling pathway (e.g., ACACA, ACSL, and ACSS) and Gene Ontology terms related to lipid metabolism and lipid biosynthetic processes. Integrated interpretation of upregulated genes indicated enrichment in genes encoding plasma membrane proteins and proteins regulating protein kinase activity. Overall, our results indicate that FO-MFD is associated with the downregulation of key genes involved in the mammary lipogenesis process. In addition, the results also suggest that this syndrome may be related to upregulation of other genes implicated in signal transduction and codification of transcription factors. PMID:28378756

  12. Putative Aspergillus niger-induced oxalate nephrosis in sheep : clinical communication

    Directory of Open Access Journals (Sweden)

    C.J. Botha

    2009-05-01

    Full Text Available A sheep farmer provided a maize-based brewer's grain (mieliemaroek and bales of Eragrostis curvula hay to ewes and their lambs, kept on zero-grazing in pens. The 'mieliemaroek' was visibly mouldy. After 14 days in the feedlot, clinical signs, including generalised weakness, ataxia of the hind limbs, tremors and recumbency, were noticed. Six ewes died within a period of 7 days. A post mortem examination was performed on 1 ewe. The carcass appeared to be cachectic with mild effusions into the body cavities; mild lung congestion and pallor of the kidneys were observed. Microscopical evaluation revealed nephrosis and birefringent oxalate crystals in the renal tubules when viewed under polarised light. A provisional diagnosis of oxalate nephrosis with subsequent kidney failure was made. Amongst other fungi, Aspergillus niger was isolated from 'mieliemaroek' samples submitted for fungal culture and identification. As A. niger is known to synthesise oxalates, a qualitative screen to detect oxalic acid in the mieliemaroek and purified A. niger isolates was performed using high-performance liquid chromatography (HPLC. Oxalic acid was detected, which supported a diagnosis of soluble oxalate-induced nephropathy.

  13. ACARDIAC TWIN

    OpenAIRE

    Vinayachandran; Jyothi,; Bindu; Umadevi

    2014-01-01

    Acardiac twin is a very rare complication occurring in monozygotic twins in which one fetus develops normally (pump twin) and the other (recipient twin) demonstrate cardiac non development and othe r anomalies. This may represent an extreme form of TTTS, also referred to as TRAP sequence. 1,2,

  14. Vaccination with recombinant adenoviruses expressing the peste des petits ruminants virus F or H proteins overcomes viral immunosuppression and induces protective immunity against PPRV challenge in sheep.

    Science.gov (United States)

    Rojas, José M; Moreno, Héctor; Valcárcel, Félix; Peña, Lourdes; Sevilla, Noemí; Martín, Verónica

    2014-01-01

    Peste des petits ruminants (PPR) is a highly contagious disease of small ruminants caused by the Morbillivirus peste des petits ruminants virus (PPRV). Two recombinant replication-defective human adenoviruses serotype 5 (Ad5) expressing either the highly immunogenic fusion protein (F) or hemagglutinin protein (H) from PPRV were used to vaccinate sheep by intramuscular inoculation. Both recombinant adenovirus vaccines elicited PPRV-specific B- and T-cell responses. Thus, neutralizing antibodies were detected in sera from immunized sheep. In addition, we detected a significant antigen specific T-cell response in vaccinated sheep against two different PPRV strains, indicating that the vaccine induced heterologous T cell responses. Importantly, no clinical signs and undetectable virus shedding were observed after virulent PPRV challenge in vaccinated sheep. These vaccines also overcame the T cell immunosuppression induced by PPRV in control animals. The results indicate that these adenovirus constructs could be a promising alternative to current vaccine strategies for the development of PPRV DIVA vaccines.

  15. Isolated pregnancy-induced anti-thrombin deficiency in a woman with twin pregnancy.

    Science.gov (United States)

    Kawabata, Kosuke; Morikawa, Mamoru; Yamada, Takahiro; Minakami, Hisanori

    2016-06-01

    A woman with twin pregnancy had a gradual decline in anti-thrombin (AT) activity from 72% at gestational week (GW) 29(-3/7) , to 53% at GW31(-2/7) , and to 41% at GW32(-2/7) , at which time hypertension (148/90 mmHg) and proteinuria (protein-to-creatinine ratio [P/Cr], 0.79 mg/mg) developed in the presence of normal platelet count (159 × 10(9) /L) and serum aspartate aminotransferase/lactate dehydrogenase (22/164 IU/L). AT product was given three times to maintain AT activity >50% and blood pressure was maintained below 155/95 mmHg with no treatment, but generalized edema with a weekly weight gain of 4.9 kg and increased proteinuria (to P/Cr, 7.6 mg/mg) required cesarean section at GW33(-3/7) . This case highlights the occurrence of pregnancy-induced AT deficiency alone in the absence of any other abnormality, including hypertension, proteinuria, or thrombocytopenia. Measurement of AT activity was considered helpful for determination of the appropriate time for delivery in this patient.

  16. Anglesite (PbSO4) epitactic overgrowths and substrate-induced twinning on anhydrite (CaSO4) cleavage surfaces

    Science.gov (United States)

    Morales, Juan; Astilleros, José Manuel; Fernández-Díaz, Lurdes; Álvarez-Lloret, Pedro; Jiménez, Amalia

    2013-10-01

    The dissolution-precipitation reactions occurring on mineral surfaces are considered an effective means to remove high amounts of dissolved toxic metals from fluid phases by precipitation of a new solid in whose structures the pollutant is immobilized. However, for these reactions to be efficient a continuous communication between the fluid and mineral phases is required. This communication can be significantly hindered when the new solid phase forms a continuous, homogeneous layer on the mineral substrate. The formation of such a layer is more likely to occur when epitactic relationships exist between the newly formed phase and the mineral substrate. Dissolved lead can be removed by interaction of the Pb-bearing aqueous solution with anhydrite (CaSO4) leading to the formation of anglesite (PbSO4). Here, the relationship between anglesite crystals and an anhydrite substrate is investigated. The three main anhydrite cleavage surfaces, (100), (010), and (001) are considered. A high density of oriented anglesite crystals growing with their (210) plane parallel to the substrate was observed on (001)Anh. The density of oriented anglesite was, however, significantly lower on (100)Anh and almost negligible on (010)Anh. Anglesite grew with its (001) plane parallel to the substrate on (100)Anh, but no evident epitactic relationship was found with (010)Anh. Differences in anglesite crystal density are explained on the grounds of structural similarities and the goodness of anglesite-anhydrite matching through the interface. Both on anhydrite (100) and (001) anglesite crystals show at least two specific orientations, which relate to each other through symmetry operators present in the substrate. The coalescence of differently oriented anglesite crystals leads to the formation of twins. This twinning phenomenon is designated as substrate-induced twinning, since the twinning law is determined by the substrate symmetry. In the particular case of anglesite growing on anhydrite

  17. Small ruminant lentivirus-induced arthritis: clinicopathologic findings in sheep infected by a highly replicative SRLV B2 genotype.

    Science.gov (United States)

    Pérez, M; Biescas, E; Reina, R; Glaria, I; Marín, B; Marquina, A; Salazar, E; Álvarez, N; de Andrés, D; Fantova, E; Badiola, J J; Amorena, B; Luján, L

    2015-01-01

    We describe the clinicopathologic features of an arthritis outbreak in sheep induced by small ruminant lentivirus (SRLV), linked to the presence of a new SRLV isolate phylogenetically assigned to caprine arthritis encephalitis virus-like subgroup B2. Thirteen SRLV seropositive Rasa Aragonesa adult ewes were selected from 5 SRLV highly infected flocks (mean seroprevalence, 90.7%) for presenting uni- or bilateral chronic arthritis in the carpal joint. A complete study was performed, including symptomatology, histopathology, immunocytochemistry, immunohistochemistry, in situ hybridization, and microbiology. The carpus was the joint almost exclusively affected, with 10 sheep (76%) showing a moderate increase in carpal joint size (diameter range, 18-20 cm; normal range, 15-16 cm) without signs of locomotion problems and with 3 ewes (23%) showing severe inflammation with marked increase in diameter (21-24 cm), pain at palpation, and abnormal standing position. Grossly, chronic proliferative arthritis was observed in affected joints characterized by an increased thickness of the synovial capsule and synovial membrane proliferation. Microscopically, synovial membrane inflammation and proliferation and hyperplasia of synoviocytes were observed. More positive cases of SLRV infection were detected by immunocytochemistry of articular fluid than of bronchoalveolar lavage fluid. Immunohistochemistry and in situ hybridization also detected positive cells in the subsynovial connective tissue, lung, mediastinal lymph node, mammary gland, and mammary lymph node. All animals were negative for the presence of Mycoplasma or other bacteria in the articular space. The present outbreak likely represents an adaptation of a caprine virus to sheep. Our results underline the importance of the arthritis induced by SRLV in sheep, a clinical form that might be underestimated.

  18. Mycoplasma ovipneumoniae induces inflammatory response in sheep airway epithelial cells via a MyD88-dependent TLR signaling pathway.

    Science.gov (United States)

    Xue, Di; Ma, Yan; Li, Min; Li, Yanan; Luo, Haixia; Liu, Xiaoming; Wang, Yujiong

    2015-01-15

    Mycoplasma ovipneumoniae (M. ovipneumoniae) is a bacterium that specifically infects sheep and goat and causes ovine infectious pleuropneumonia. In an effort to understand the pathogen-host interaction between the M. ovipneumoniae and airway epithelial cells, we investigated the host inflammatory response using a primary air-liquid interface (ALI) epithelial culture model generated from bronchial epithelial cells of Ningxia Tan sheep (Ovis aries). The ALI culture of sheep bronchial epithelial cells showed a fully differentiated epithelium comprising distinct epithelial types, including the basal, ciliated and goblet cells. Exposure of ALI cultures to M. ovipneumoniae led to increased expression of Toll-like receptors (TLRs), and components of the myeloid differentiation factor 88 (MyD88)-dependent TLR signaling pathway, including the MyD88, TNF receptor-associated factor 6 (TRAF6), IL-1 receptor-associated kinases (IRAKs) and nuclear factor-kappa B (NF-κB), as well as subsequent pro-inflammatory cytokines in the epithelial cells. Of interest, infection with M. ovipneumoniae failed to induce the expression of TANK-binding kinase 1 (TBK1), TRAF3 and interferon regulatory factor 3 (IRF3), key components of the MyD88-independent signaling pathway. These results suggest that the MyD88-dependent TLR pathway may play a crucial role in sheep airway epithelial cells in response to M. ovipneumoniae infection, which also indicate that the ALI culture system may be a reliable model for investigating pathogen-host interactions between M. ovipneumoniae and airway epithelial cells.

  19. Deformation twinning induced decomposition of lamellar LPSO structure and its re-precipitation in an Mg-Zn-Y alloy

    Science.gov (United States)

    Shao, X. H.; Zheng, S. J.; Chen, D.; Jin, Q. Q.; Peng, Z. Z.; Ma, X. L.

    2016-07-01

    The high hardness or yield strength of an alloy is known to benefit from the presence of small-scale precipitation, whose hardening effect is extensively applied in various engineering materials. Stability of the precipitates is of critical importance in maintaining the high performance of a material under mechanical loading. The long period stacking ordered (LPSO) structures play an important role in tuning the mechanical properties of an Mg-alloy. Here, we report deformation twinning induces decomposition of lamellar LPSO structures and their re-precipitation in an Mg-Zn-Y alloy. Using atomic resolution scanning transmission electron microscopy (STEM), we directly illustrate that the misfit dislocations at the interface between the lamellar LPSO structure and the deformation twin is corresponding to the decomposition and re-precipitation of LPSO structure, owing to dislocation effects on redistribution of Zn/Y atoms. This finding demonstrates that deformation twinning could destabilize complex precipitates. An occurrence of decomposition and re-precipitation, leading to a variant spatial distribution of the precipitates under plastic loading, may significantly affect the precipitation strengthening.

  20. Stress-induced decrease of uterine blood flow in sheep is mediated by alpha 1-adrenergic receptors.

    Science.gov (United States)

    Dreiling, Michelle; Bischoff, Sabine; Schiffner, Rene; Rupprecht, Sven; Kiehntopf, Michael; Schubert, Harald; Witte, Otto W; Nathanielsz, Peter W; Schwab, Matthias; Rakers, Florian

    2016-09-01

    Prenatal maternal stress can be transferred to the fetus via a catecholamine-dependent decrease of uterine blood flow (UBF). However, it is unclear which group of adrenergic receptors mediates this mechanism of maternal-fetal stress transfer. We hypothesized that in sheep, alpha 1-adrenergic receptors may play a key role in catecholamine mediated UBF decrease, as these receptors are mainly involved in peripheral vasoconstriction and are present in significant number in the uterine vasculature. After chronic instrumentation at 125 ± 1 days of gestation (dGA; term 150 dGA), nine pregnant sheep were exposed at 130 ± 1 dGA to acute isolation stress for one hour without visual, tactile, or auditory contact with their flockmates. UBF, blood pressure (BP), heart rate (HR), stress hormones, and blood gases were determined before and during this isolation challenge. Twenty-four hours later, experiments were repeated during alpha 1-adrenergic receptor blockage induced by a continuous intravenous infusion of urapidil. In both experiments, ewes reacted to isolation with an increase in serum norepinephrine, cortisol, BP, and HR as typical signs of activation of sympatho-adrenal and the hypothalamic-pituitary-adrenal axis. Stress-induced UBF decrease was prevented by alpha 1-adrenergic receptor blockage. We conclude that UBF decrease induced by maternal stress in sheep is mediated by alpha 1-adrenergic receptors. Future studies investigating prevention strategies of impact of prenatal maternal stress on fetal health should consider selective blockage of alpha 1-receptors to interrupt maternal-fetal stress transfer mediated by utero-placental malperfusion.

  1. Twin births

    DEFF Research Database (Denmark)

    Hoffmann, Elise; Oldenburg, Anna; Rode, Line;

    2012-01-01

    To assess morbidity and mortality in twin pregnancy deliveries, according to chorionicity and mode of delivery.......To assess morbidity and mortality in twin pregnancy deliveries, according to chorionicity and mode of delivery....

  2. Maternal anti-M induced hemolytic disease of newborn followed by prolonged anemia in newborn twins

    Directory of Open Access Journals (Sweden)

    Satyam Arora

    2015-01-01

    Full Text Available Allo-anti-M often has an immunoglobulin G (IgG component but is rarely clinically significant. We report a case of hemolytic disease of the fetus and newborn along with prolonged anemia in newborn twins that persisted for up to 70 days postbirth. The aim was to diagnose and successfully manage hemolytic disease of newborn (HDN due to maternal alloimmunization. Direct antiglobulin test (DAT, antigen typing, irregular antibody screening and identification were done by polyspecific antihuman globulin cards and standard tube method. At presentation, the newborn twins (T1, T2 had HDN with resultant low reticulocyte count and prolonged anemia, which continued for up to 70 days of life. Blood group of the twins and the mother was O RhD positive. DAT of the both newborns at birth was negative. Anti-M was detected in mothers as well as newborns. Type of antibody in mother was IgG and IgM type whereas in twins it was IgG type only. M antigen negative blood was transfused thrice to twin-1 and twice to twin-2. Recurring reduction of the hematocrit along with low reticulocyte count and normal other cell line indicated a pure red cell aplastic state. Anti-M is capable of causing HDN as well as prolonged anemia (red cell aplasia due to its ability to destroy the erythroid precursor cells. Newborns with anemia should be evaluated for all the possible causes to establish a diagnosis and its efficient management. Mother should be closely monitored for future pregnancies as well.

  3. Concentration-dependent effects of cocaine on monoamine-induced constriction of cannulated, pressurized cerebral arteries from fetal sheep.

    Science.gov (United States)

    Schreiber, M D; Madden, J A; Covert, R F; Hershenson, M B; Torgerson, L J

    1995-01-01

    Drugs, such as cocaine, which may alter monoamine neurotransmitter responsiveness, could adversely affect the regulation of cerebral vasculature. Cocaine exhibits at least two mechanisms that may alter vascular responsiveness: synaptic uptake inhibition, which may augment response to stimulation, and Na+ channel inhibition, which may attenuate response. To help elicit the concentration-dependent effects of cocaine, the effects of cocaine on monoamine neurotransmitter responsiveness were studied in vitro on fetal sheep cerebral arteries (120 days gestation). The changes in diameter of segments of cannulated, pressurized fetal sheep cerebral artery were measured with a videomicroscaler system. Cumulative concentration-response curves (10(-10) to 10(-4)M) were generated for two monoamines, norepinephrine and serotonin, alone and in the presence of cocaine (10(-5) or 10(-4)M). Cocaine caused concentration-dependent alteration of response. At 10(-4)M, cocaine attenuated mean maximal norepinephrine-induced vasoconstriction 46.2% (P < 0.05). At 10(-5)M, cocaine increased sensitivity to norepinephrine (log EC50 decreased -6.63 +/- 0.09 to -7.11 +/- 0.03) and to serotonin (log EC50 decreased -7.24 +/- 0.04 to -7.81 +/- 0.09) (P < 0.05). The higher concentration of cocaine (10(-4)M) did not significantly decrease log EC50 norepinephrine. Cocaine (10(-4)M) also attenuated the response to single doses of norepinephrine (10(-6)M) and serotonin (10(-6)M) by 26.5% and 40.0%, respectively (P < or = 0.05). It is concluded that cocaine has concentration-dependent effects on vasoconstriction of the fetal sheep cerebral artery in vitro. This cocaine-induced alteration of cerebral vascular responsiveness to monoamines may be important in the regulation of fetal cerebral blood flow.

  4. Phase-Field Analysis of Fracture-Induced Twinning in Single Crystals

    Science.gov (United States)

    2013-07-01

    4]. Indentation experiments on ceramics and minerals often show evidence of both fracture and twinning, with surface damage strongly promoting the...tip. Phys Rev Lett 2011;107:085505. [14] Idesman A, Levitas V, Stein E. Structural changes in elastoplastic material: a unified finite-element approach

  5. Use of estradiol benzoate to induce ovulation in a short-term protocol for fixed-time AI in sheep

    Directory of Open Access Journals (Sweden)

    Caliê Castilho

    2015-06-01

    Full Text Available The aim of this study was to test the hormonal protocol for fixed-time artificial insemination (TAI with a progesterone vaginal device for six days applying equine chorionic gonadotropin (eCG or estradiol benzoate (EB as an ovulation inducer in ewes. On day 0 (D0, the ewes (n=31 received a device containing 0.33 g of intravaginal progesterone (CIDR® and were divided into three groups. The G-CT (control group used CIDR for nine days and upon withdrawal of the progesterone, were administered prostaglandin F2 alpha (PGF2? and eCG. In the eCG (G-eCG group, CIDR was administered for six days, instead of nine as in the G-CT group, followed by PGF2a and eCG after progesterone withdrawal. In the EB (G-EB group, CIDR was also administered for six days, but eCG was not applied, and EB was used to induce ovulation 24 hours after removing the CIDR and PGF2a application. TAI was realized in all groups 50 hours after CIDR withdrawal. The pregnancy rate in the G-eCG group (66% was higher (p 0.05 compared to the G-CT group (30%. It is possible to reduce the application time of the progesterone and use eCG for TAI in sheep; however, using EB resulted in a low ovulation rate in the sheep.

  6. Directly auto-transplanted mesenchymal stem cells induce bone formation in a ceramic bone substitute in an ectopic sheep model

    Science.gov (United States)

    Boos, Anja M; Loew, Johanna S; Deschler, Gloria; Arkudas, Andreas; Bleiziffer, Oliver; Gulle, Heinz; Dragu, Adrian; Kneser, Ulrich; Horch, Raymund E; Beier, Justus P

    2011-01-01

    Abstract Bone tissue engineering approaches increasingly focus on the use of mesenchymal stem cells (MSC). In most animal transplantation models MSC are isolated and expanded before auto cell transplantation which might be critical for clinical application in the future. Hence this study compares the potential of directly auto-transplanted versus in vitro expanded MSC with or without bone morphogenetic protein-2 (BMP-2) to induce bone formation in a large volume ceramic bone substitute in the sheep model. MSC were isolated from bone marrow aspirates and directly auto-transplanted or expanded in vitro and characterized using fluorescence activated cell sorting (FACS) and RT-PCR analysis before subcutaneous implantation in combination with BMP-2 and β-tricalcium phosphate/hydroxyapatite (β-TCP/HA) granules. Constructs were explanted after 1 to 12 weeks followed by histological and RT-PCR evaluation. Sheep MSC were CD29+, CD44+ and CD166+ after selection by Ficoll gradient centrifugation, while directly auto-transplanted MSC-populations expressed CD29 and CD166 at lower levels. Both, directly auto-transplanted and expanded MSC, were constantly proliferating and had a decreasing apoptosis over time in vivo. Directly auto-transplanted MSC led to de novo bone formation in a heterotopic sheep model using a β-TCP/HA matrix comparable to the application of 60 μg/ml BMP-2 only or implantation of expanded MSC. Bone matrix proteins were up-regulated in constructs following direct auto-transplantation and in expanded MSC as well as in BMP-2 constructs. Up-regulation was detected using immunohistology methods and RT-PCR. Dense vascularization was demonstrated by CD31 immunohistology staining in all three groups. Ectopic bone could be generated using directly auto-transplanted or expanded MSC with β-TCP/HA granules alone. Hence BMP-2 stimulation might become dispensable in the future, thus providing an attractive, clinically feasible approach to bone tissue engineering. PMID

  7. Twin pregnancy

    DEFF Research Database (Denmark)

    Sperling, Lene; Tabor, A

    2001-01-01

    Determination of chorionicity is one of the most important issues in the management of twin pregnancy. Modern ultrasound equipment has made it possible to accurately assess placentation already in the first trimester with the lambda sign. With regard to prenatal diagnosis, it is important to know...... for clinicians caring for twin pregnancies....

  8. Action of larch bark in the regulation of cortisol induced stress in sheep

    Directory of Open Access Journals (Sweden)

    Elisa Asquini

    2010-01-01

    Full Text Available The effect of Larix decidua (LD dietary administration on gene expression patterns has been evaluated in sheep under ACTH challenge. Experimental protocol was approved by local laws and regulations. Eighteen sheep at maintenance were allotted to 3 groups: CTR (negative control, without ACTH, and supplementation, ACTH (positive control, with ACTH, and without supplementation, LD (ACTH and 50 g/head/day of LD. ACTH was injected for 3 subsequent days to ACTH and LD groups and blood was sampled before (T0 and after 3 (T3 and 51 (T51 hours from the first injection. RNA extracted samples were pooled together within group and time of sampling. A custom oligoarray was synthesized using 24,384 35 -40mer probes designed from 12,194 UniGenes (NCBI on a CombiMatrix 90K platform. Cy5 labelled samples were hybridized on the chip. Statistical analysis, performed with MeV software 4.1 (TIGR, allowed the identification of a set of genes which were up or down regulated as a consequence of ACTH treatment. Genes that resulted differentially expressed were annotated with HomoloGene system and data mining was performed with Babelomics v3.1 tool. Functional analysis showed that most of the differentially expressed genes belong to KEGG pathways involved in immune system response and signaling molecules and interaction. Larch administration was effective in counteracting the effect of ACTH injection on the inflammatory processes, restoring the physiological homeostasis.

  9. Investigation of Deformation Mechanisms in Deep-Drawn and Tensile-Strained Austenitic Mn-Based Twinning Induced Plasticity (TWIP) Steel

    NARCIS (Netherlands)

    Van Tol, R.T.; Zhao, L.; Schut, H.; Sietsma, J.

    2012-01-01

    The effect of strain on the deformation mechanisms in an austenitic Mn-based twinning induced plasticity (TWIP) steel is investigated using magnetic measurements, XRD, positron beam Doppler spectroscopy, and finite element method simulations. The experimental observations reveal the formation of a0-

  10. Hypertensive disorders in twin pregnancy

    NARCIS (Netherlands)

    J.G. Santema (Job); E. Koppelaar (Elin); H.C.S. Wallenburg (Henk)

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending th

  11. Interstitial atoms enable joint twinning and transformation induced plasticity in strong and ductile high-entropy alloys

    Science.gov (United States)

    Li, Zhiming; Tasan, Cemal Cem; Springer, Hauke; Gault, Baptiste; Raabe, Dierk

    2017-01-01

    High-entropy alloys (HEAs) consisting of multiple principle elements provide an avenue for realizing exceptional mechanical, physical and chemical properties. We report a novel strategy for designing a new class of HEAs incorporating the additional interstitial element carbon. This results in joint activation of twinning- and transformation-induced plasticity (TWIP and TRIP) by tuning the matrix phase’s instability in a metastable TRIP-assisted dual-phase HEA. Besides TWIP and TRIP, such alloys benefit from massive substitutional and interstitial solid solution strengthening as well as from the composite effect associated with its dual-phase structure. Nanosize particle formation and grain size reduction are also utilized. The new interstitial TWIP-TRIP-HEA thus unifies all metallic strengthening mechanisms in one material, leading to twice the tensile strength compared to a single-phase HEA with similar composition, yet, at identical ductility.

  12. Intranasal infection with Chlamydia abortus induces dose-dependent latency and abortion in sheep.

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    David Longbottom

    Full Text Available BACKGROUND: Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus. METHODOLOGY/PRINCIPAL FINDINGS: Three groups of sheep (groups 1, 2 and 3 were experimentally infected with different doses of C. abortus (5×10(3, 5×10(5 and 5×10(7 inclusion forming units (IFU, respectively prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b or were inoculated subcutaneously on day 70 of gestation with 2×10(6 IFU C. abortus (group 5. Animals in groups 1, 2 and 5 experienced an abortion rate of 50-67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium. CONCLUSIONS/SIGNIFICANCE: The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and

  13. Vaccination with recombinant adenoviruses expressing the peste des petits ruminants virus F or H proteins overcomes viral immunosuppression and induces protective immunity against PPRV challenge in sheep.

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    José M Rojas

    Full Text Available Peste des petits ruminants (PPR is a highly contagious disease of small ruminants caused by the Morbillivirus peste des petits ruminants virus (PPRV. Two recombinant replication-defective human adenoviruses serotype 5 (Ad5 expressing either the highly immunogenic fusion protein (F or hemagglutinin protein (H from PPRV were used to vaccinate sheep by intramuscular inoculation. Both recombinant adenovirus vaccines elicited PPRV-specific B- and T-cell responses. Thus, neutralizing antibodies were detected in sera from immunized sheep. In addition, we detected a significant antigen specific T-cell response in vaccinated sheep against two different PPRV strains, indicating that the vaccine induced heterologous T cell responses. Importantly, no clinical signs and undetectable virus shedding were observed after virulent PPRV challenge in vaccinated sheep. These vaccines also overcame the T cell immunosuppression induced by PPRV in control animals. The results indicate that these adenovirus constructs could be a promising alternative to current vaccine strategies for the development of PPRV DIVA vaccines.

  14. Serological monitoring of protection of sheep against Echinococcus granulosus induced by the EG95 vaccine.

    Science.gov (United States)

    Heath, D D; Koolaard, J

    2012-01-01

    Although immunity to Echinococcus granulosus in sheep has been shown to be antibody-mediated and complement-dependent and can be passively transferred in colostrum, in animals vaccinated with EG95, the relationship between protection against an oral challenge infection with E. granulosus eggs and anti-EG95 IgG ELISA absorbance values at the time of challenge has not been satisfactorily proven. Using a combination of results from three EG95 vaccination trials, we have found that the IgG ELISA absorbance at the time of challenge infection explains approximately 50% (P ≤ 0·001) of the variability in the percentage protection against an oral challenge with E. granulosus eggs (transformed with arcsin).

  15. Twin-Induced InSb Nanosails: A Convenient High Mobility Quantum System.

    Science.gov (United States)

    de la Mata, María; Leturcq, Renaud; Plissard, Sébastien R; Rolland, Chloé; Magén, César; Arbiol, Jordi; Caroff, Philippe

    2016-02-10

    Ultra narrow bandgap III-V semiconductor nanomaterials provide a unique platform for realizing advanced nanoelectronics, thermoelectrics, infrared photodetection, and quantum transport physics. In this work we employ molecular beam epitaxy to synthesize novel nanosheet-like InSb nanostructures exhibiting superior electronic performance. Through careful morphological and crystallographic characterization we show how this unique geometry is the result of a single twinning event in an otherwise pure zinc blende structure. Four-terminal electrical measurements performed in both the Hall and van der Pauw configurations reveal a room temperature electron mobility greater than 12,000 cm(2)·V(-1)·s(-1). Quantized conductance in a quantum point contact processed with a split-gate configuration is also demonstrated. We thus introduce InSb "nanosails" as a versatile and convenient platform for realizing new device and physics experiments with a strong interplay between electronic and spin degrees of freedom.

  16. Coexistence of epitaxial lattice rotation and twinning tilt induced by surface symmetry mismatch

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, L., E-mail: qiaol@ornl.gov, E-mail: biegalskim@ornl.gov; Biegalski, M. D., E-mail: qiaol@ornl.gov, E-mail: biegalskim@ornl.gov [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Xiao, H. Y. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Weber, W. J. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States)

    2014-06-02

    Combined x-ray diffraction and first-principles studies of various epitaxial rutile-type metal dioxide films on Al{sub 2}O{sub 3}(0001) substrates reveal an unexpected rectangle-on-parallelogram heteroepitaxy. Unique matching of particular lattice spacings and crystal angles between the oxygen sublattices of Al{sub 2}O{sub 3}(0001) and the film(100) result in coexisted crystal rotation and lattice twinning inside the film. We demonstrate that, besides symmetry and lattice mismatch, angular mismatch along a specific crystal direction is also an important factor determining epitaxy. A generalized theorem has been proposed to explain epitaxial behaviors for tetragonal metal dioxides on Al{sub 2}O{sub 3}(0001).

  17. Corticosteroid administration modifies ozone-induced increases in sheep airway blood flow

    Energy Technology Data Exchange (ETDEWEB)

    Gunther, R.A.; Yousef, M.A.; Schelegle, E.S.; Cross, C.E. (Department of Surgery, School of Medicine, University of California, Davis (United States))

    1992-09-01

    Recently, we have shown that exposure of intubated conscious sheep to 3 to 4 ppm ozone (O3) for 3 h increases bronchial blood flow (Qbr). The purpose of the present study was to assess the potential role of corticosteroids in modulating this increase. Six nasally intubated sheep were exposed to filtered room air, 3.5 ppm O3 on two separate occasions, and 3.5 ppm O3 plus methyl-prednisone, for 3 h. Qbr was measured using a chronically implanted 20 MHz pulsed Doppler flow probe. Qbr, mean aortic pressure, cardiac output, pulmonary artery pressure, arterial blood gases, and core temperature were monitored. After 3 h of 3.5 ppm O3, Qbr increased from 3.2 +/- 0.5 (mean +/- SEM) to 8.5 +/- 1.6 KHz, whereas bronchial vascular resistance (BVR) decreased from the baseline value of 43.6 +/- 8.0 to 15.0 +/- 3 mm Hg/KHz. With corticosteroids, baseline Qbr was 3.2 +/- 0.6 and BVR was 44.2 +/- 9.7; after 3 h of 3.5 ppm O3, Qbr was 3.3 +/- 0.5 KHz and BVR was 39.0 +/- 8.0 mm Hg/KHz. The two 3.5-ppm O3 exposures without corticosteroids were impressively reproducible. Except for Qbr and BVR, no other measured cardiovascular parameters were affected by O3. The results indicate that corticosteroids are capable of interfering with mediator, neurohumoral, or inflammatory cell mechanisms responsible for vasodilation of the airway microcirculation after O3 exposure, but do not specifically address the specific processes whereby this attenuation occurs.

  18. The behaviour of fatigue-induced microdamage in compact bone samples from control and ovariectomised sheep.

    Science.gov (United States)

    Kennedy, Oran D; Brennan, Orlaith; Mauer, Peter; O'Brien, Fergal J; Rackard, Susan M; Taylor, David; Lee, T Clive

    2008-01-01

    This study investigates the effect of microdamage on bone quality in osteoporosis using an ovariectomised (OVX) sheep model of osteoporosis. Thirty-four sheep were divided into an OVX group (n=16) and a control group (n=18). Fluorochromes were administered intravenously at 3 monthly intervals after surgery to label bone turnover. After sacrifice, beams were removed from the metatarsal and tested in three-point bending. Following failure, microcracks were identified and quantified in terms of region, location and interaction with osteons. Number of cycles to failure (Nf) was lower in the OVX group relative to controls by approximately 7%. Crack density (CrDn) was higher in the OVX group compared to controls. CrDn was 2.5 and 3.5 times greater in the compressive region compared to tensile in control and OVX bone respectively. Combined results from both groups showed that 91% of cracks remained in interstitial bone, approximately 8% of cracks penetrated unlabelled osteons and less than 1% penetrated into labelled osteons. All cases of labelled osteon penetration occurred in controls. Crack surface density (CrSDn), was 25% higher in the control group compared to OVX. It is known that crack behaviour on meeting microstructural features such as osteons will depend on crack length. We have shown that osteon age also affects crack propagation. Long cracks penetrated unlabelled osteons but not labelled ones. Some cracks in the control group did penetrate labelled osteons. This may be due the fact that control bone is more highly mineralized. CrSDn was increased by 25% in the control group compared to OVX. Further study of these fracture mechanisms will help determine the effect of microdamage on bone quality and how this contributes to bone fragility.

  19. Protein-releasing polymeric scaffolds induce fibrochondrocytic differentiation of endogenous cells for knee meniscus regeneration in sheep.

    Science.gov (United States)

    Lee, Chang H; Rodeo, Scott A; Fortier, Lisa Ann; Lu, Chuanyong; Erisken, Cevat; Mao, Jeremy J

    2014-12-10

    Regeneration of complex tissues, such as kidney, liver, and cartilage, continues to be a scientific and translational challenge. Survival of ex vivo cultured, transplanted cells in tissue grafts is among one of the key barriers. Meniscus is a complex tissue consisting of collagen fibers and proteoglycans with gradient phenotypes of fibrocartilage and functions to provide congruence of the knee joint, without which the patient is likely to develop arthritis. Endogenous stem/progenitor cells regenerated the knee meniscus upon spatially released human connective tissue growth factor (CTGF) and transforming growth factor-β3 (TGFβ3) from a three-dimensional (3D)-printed biomaterial, enabling functional knee recovery. Sequentially applied CTGF and TGFβ3 were necessary and sufficient to propel mesenchymal stem/progenitor cells, as a heterogeneous population or as single-cell progenies, into fibrochondrocytes that concurrently synthesized procollagens I and IIα. When released from microchannels of 3D-printed, human meniscus scaffolds, CTGF and TGFβ3 induced endogenous stem/progenitor cells to differentiate and synthesize zone-specific type I and II collagens. We then replaced sheep meniscus with anatomically correct, 3D-printed scaffolds that incorporated spatially delivered CTGF and TGFβ3. Endogenous cells regenerated the meniscus with zone-specific matrix phenotypes: primarily type I collagen in the outer zone, and type II collagen in the inner zone, reminiscent of the native meniscus. Spatiotemporally delivered CTGF and TGFβ3 also restored inhomogeneous mechanical properties in the regenerated sheep meniscus. Survival and directed differentiation of endogenous cells in a tissue defect may have implications in the regeneration of complex (heterogeneous) tissues and organs.

  20. High-dose hydroxocobalamin administered after H2S exposure counteracts sulfide-poisoning-induced cardiac depression in sheep.

    Science.gov (United States)

    Haouzi, Philippe; Chenuel, Bruno; Sonobe, Takashi

    2015-01-01

    Severe H2S poisoning leads to death by rapid respiratory and cardiac arrest, the latter can occur within seconds or minutes in severe forms of intoxication. To determine the time course and the nature of H2S-induced cardiac arrest and the effects of high-dose hydroxocobalamin administered after the end of sulfide exposure. NaHS was infused in 16 sedated mechanically ventilated sheep to reach concentrations of H2S in the blood, which was previously found to lead to cardiac arrest within minutes following the cessation of H2S exposure. High-dose hydroxocobalamin (5 g) or saline solution was administered intravenously, 1 min after the cessation of NaHS infusion. All animals were still alive at the cessation of H2S exposure. Three animals (18%) presented a cardiac arrest within 90 s and were unable to receive any antidote or vehicle. In the animals that survived long enough to receive either hydroxocobalamin or saline, 71% (5/7) died in the control group by cardiac arrest within 10 min. In all instances, cardiac arrest was the result of a pulseless electrical activity (PEA). In the group that received the antidote, intravenous injection of 5 g of hydroxocobalamin provoked an abrupt increase in blood pressure and blood flow; PEA was prevented in all instances. However, we could not find any evidence for a recovery in oxidative metabolism in the group receiving hydroxocobalamin, as blood lactate remained elevated and even continued to rise after 1 h, despite restored hemodynamics. This, along with an unaltered recovery of H2S kinetics, suggests that hydroxocobalamin did not act through a mechanism of H2S trapping. In this sheep model, there was a high risk for cardiac arrest, by PEA, persisting up to 10 min after H2S exposure. Very high dose of hydroxocobalamin (5 g), injected very early after the cessation of H2S exposure, improved cardiac contractility and prevented PEA.

  1. Rumen microbial and fermentation characteristics are affected differently by bacterial probiotic supplementation during induced lactic and subacute acidosis in sheep

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    Lettat Abderzak

    2012-07-01

    Full Text Available Abstract Background Ruminal disbiosis induced by feeding is the cause of ruminal acidosis, a digestive disorder prevalent in high-producing ruminants. Because probiotic microorganisms can modulate the gastrointestinal microbiota, propionibacteria- and lactobacilli-based probiotics were tested for their effectiveness in preventing different forms of acidosis. Results Lactic acidosis, butyric and propionic subacute ruminal acidosis (SARA were induced by feed chalenges in three groups of four wethers intraruminally dosed with wheat, corn or beet pulp. In each group, wethers were either not supplemented (C or supplemented with Propionibacterium P63 alone (P or combined with L. plantarum (Lp + P or L. rhamnosus (Lr + P. Compared with C, all the probiotics stimulated lactobacilli proliferation, which reached up to 25% of total bacteria during wheat-induced lactic acidosis. This induced a large increase in lactate concentration, which decreased ruminal pH. During the corn-induced butyric SARA, Lp + P decreased Prevotella spp. proportion with a concomitant decrease in microbial amylase activity and total volatile fatty acids concentration, and an increase in xylanase activity and pH. Relative to the beet pulp-induced propionic SARA, P and Lr + P improved ruminal pH without affecting the microbial or fermentation characteristics. Regardless of acidosis type, denaturing gradient gel electrophoresis revealed that probiotic supplementations modified the bacterial community structure. Conclusion This work showed that the effectiveness of the bacterial probiotics tested depended on the acidosis type. Although these probiotics were ineffective in lactic acidosis because of a deeply disturbed rumen microbiota, some of the probiotics tested may be useful to minimize the occurrence of butyric and propionic SARA in sheep. However, their modes of action need to be further investigated.

  2. Rumen microbial and fermentation characteristics are affected differently by bacterial probiotic supplementation during induced lactic and subacute acidosis in sheep

    Science.gov (United States)

    2012-01-01

    Background Ruminal disbiosis induced by feeding is the cause of ruminal acidosis, a digestive disorder prevalent in high-producing ruminants. Because probiotic microorganisms can modulate the gastrointestinal microbiota, propionibacteria- and lactobacilli-based probiotics were tested for their effectiveness in preventing different forms of acidosis. Results Lactic acidosis, butyric and propionic subacute ruminal acidosis (SARA) were induced by feed chalenges in three groups of four wethers intraruminally dosed with wheat, corn or beet pulp. In each group, wethers were either not supplemented (C) or supplemented with Propionibacterium P63 alone (P) or combined with L. plantarum (Lp + P) or L. rhamnosus (Lr + P). Compared with C, all the probiotics stimulated lactobacilli proliferation, which reached up to 25% of total bacteria during wheat-induced lactic acidosis. This induced a large increase in lactate concentration, which decreased ruminal pH. During the corn-induced butyric SARA, Lp + P decreased Prevotella spp. proportion with a concomitant decrease in microbial amylase activity and total volatile fatty acids concentration, and an increase in xylanase activity and pH. Relative to the beet pulp-induced propionic SARA, P and Lr + P improved ruminal pH without affecting the microbial or fermentation characteristics. Regardless of acidosis type, denaturing gradient gel electrophoresis revealed that probiotic supplementations modified the bacterial community structure. Conclusion This work showed that the effectiveness of the bacterial probiotics tested depended on the acidosis type. Although these probiotics were ineffective in lactic acidosis because of a deeply disturbed rumen microbiota, some of the probiotics tested may be useful to minimize the occurrence of butyric and propionic SARA in sheep. However, their modes of action need to be further investigated. PMID:22812531

  3. Polioencefalomalacia experimental induzida por amprólio em ovinos Experimentally amprolium-induced polioencephalomalacia in sheep

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    Fabiano J.F. de Sant'Ana

    2009-09-01

    Full Text Available Para estabelecer um modelo experimental para o estudo da etiologia, patologia e patogênese da polioencefalomalacia em ruminantes, a condição foi induzida em cinco ovinos pela administração oral de amprólio nas doses diárias de 500 e 1.000mg/kg de peso animal, respectivamente por 28-59 dias e 13-39 dias. Todos os ovinos morreram ou foram eutanasiados in extremis após um curso clínico de 3-7 dias. Os sinais clínicos incluíam depressão, incoordenação, midríase, bruxismo, cegueira e decúbito com opistótono e movimentos de pedalagem. Salivação excessiva e posição de cavalete foi observada em um ovino e mioclonias em um outro. Os principais achados de necropsia restringiam-se ao sistema nervoso central e incluíam tumefação do encéfalo com achatamento dos giros telencefálicos e hemorragias nos lobos parietal e occipital do telencéfalo; as hemorragias ocorriam também nas áreas submeníngeas da medula espinhal e do mesencéfalo. Histologicamente, havia necrose segmentar laminar de neurônios (neurônios vermelhos associada a edema, tumefação de células endoteliais, hemorragias e infiltração por macrófagos espumosos (células gitter. Essas alterações eram mais marcadas nos lobos frontal, parietal e occipital do telencéfalo e havia uma demarcação abrupta entre as lesões e o neurópilo normal adjacente. Adicionalmente, lesões semelhantes, mas menos acentuadas, eram observadas no mesencéfalo, tálamo e hipocampo. Levando em consideração a reproducibilidade regular dos aspectos da polioencefalomalacia em ovinos pela administração de amprólio, esse modelo pode ser útil para o estudo da doença.In order to establish an experimental model for the study of the etiology, pathology, and pathogenesis of polioencephalomalacia in ruminants, the condition was induced in five sheep by oral administration of amprolium at daily doses of 500 and 1,000mg per kg of body weight respectively for 28-59 days and for 13-39 days

  4. Microstructure Evolution and Mechanical Behavior of a Hot-Rolled High-Manganese Dual-Phase Transformation-Induced Plasticity/Twinning-Induced Plasticity Steel

    Science.gov (United States)

    Fu, Liming; Shan, Mokun; Zhang, Daoda; Wang, Huanrong; Wang, Wei; Shan, Aidang

    2017-05-01

    The microstructures and deformation behavior were studied in a high-temperature annealed high-manganese dual-phase (28 vol pct δ-ferrite and 72 vol pct γ-austenite) transformation-induced plasticity/twinning-induced plasticity (TRIP/TWIP) steel. The results showed that the steel exhibits a special Lüders-like yielding phenomenon at room temperature (RT) and 348 K (75 °C), while it shows continuous yielding at 423 K, 573 K and 673 K (150 °C, 300 °C and 400 °C) deformation. A significant TRIP effect takes place during Lüders-like deformation at RT and 348 K (75 °C) temperatures. Semiquantitative analysis of the TRIP effect on the Lüders-like yield phenomenon proves that a softening effect of the strain energy consumption of strain-induced transformation is mainly responsible for this Lüders-like phenomenon. The TWIP mechanism dominates the 423 K (150 °C) deformation process, while the dislocation glide controls the plasticity at 573 K (300 °C) deformation. The delta-ferrite, as a hard phase in annealed dual-phase steel, greatly affects the mechanical stability of austenite due to the heterogeneous strain distribution between the two phases during deformation. A delta-ferrite-aided TRIP effect, i.e., martensite transformation induced by localized strain concentration of the hard delta-ferrite, is proposed to explain this kind of Lüders-like phenomenon. Moreover, the tensile curve at RT exhibits an upward curved behavior in the middle deformation stage, which is principally attributed to the deformation twinning of austenite retained after Lüders-like deformation. The combination of the TRIP effect during Lüders-like deformation and the subsequent TWIP effect greatly enhances the ductility in this annealed high-manganese dual-phase TRIP/TWIP steel.

  5. Microstructure Evolution and Mechanical Behavior of a Hot-Rolled High-Manganese Dual-Phase Transformation-Induced Plasticity/Twinning-Induced Plasticity Steel

    Science.gov (United States)

    Fu, Liming; Shan, Mokun; Zhang, Daoda; Wang, Huanrong; Wang, Wei; Shan, Aidang

    2017-02-01

    The microstructures and deformation behavior were studied in a high-temperature annealed high-manganese dual-phase (28 vol pct δ-ferrite and 72 vol pct γ-austenite) transformation-induced plasticity/twinning-induced plasticity (TRIP/TWIP) steel. The results showed that the steel exhibits a special Lüders-like yielding phenomenon at room temperature (RT) and 348 K (75 °C), while it shows continuous yielding at 423 K, 573 K and 673 K (150 °C, 300 °C and 400 °C) deformation. A significant TRIP effect takes place during Lüders-like deformation at RT and 348 K (75 °C) temperatures. Semiquantitative analysis of the TRIP effect on the Lüders-like yield phenomenon proves that a softening effect of the strain energy consumption of strain-induced transformation is mainly responsible for this Lüders-like phenomenon. The TWIP mechanism dominates the 423 K (150 °C) deformation process, while the dislocation glide controls the plasticity at 573 K (300 °C) deformation. The delta-ferrite, as a hard phase in annealed dual-phase steel, greatly affects the mechanical stability of austenite due to the heterogeneous strain distribution between the two phases during deformation. A delta-ferrite-aided TRIP effect, i.e., martensite transformation induced by localized strain concentration of the hard delta-ferrite, is proposed to explain this kind of Lüders-like phenomenon. Moreover, the tensile curve at RT exhibits an upward curved behavior in the middle deformation stage, which is principally attributed to the deformation twinning of austenite retained after Lüders-like deformation. The combination of the TRIP effect during Lüders-like deformation and the subsequent TWIP effect greatly enhances the ductility in this annealed high-manganese dual-phase TRIP/TWIP steel.

  6. Healing of excisional wound in alloxan induced diabetic sheep: A planimetric and histopathologic study

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    Farshid Sarrafzadeh-Rezaei

    2013-09-01

    Full Text Available Healing of skin wound is a multi-factorial and complex process. Proper treatment of diabetic wounds is still a major clinical challenge. Although diabetes mellitus can occur in ruminants, healing of wounds in diabetic ruminants has not yet been investigated. The aim of this study was to evaluate healing of ovine excisional diabetic wound model. Eight 4-month-old Iranian Makoui wethers were equally divided to diabetic and nondiabetic groups. Alloxan monohydrate (60 mg kg-1, IV was used for diabetes induction. In each wether, an excisional wound was created on the dorsum of the animal. Photographs were taken in distinct times for planimetric evaluation. Wound samples were taken on day 21 post-wounding for histopathologic evaluations of epidermal thickness, number of fibroblasts and number of new blood vessels. The planimetric study showed slightly delay in wound closure of diabetic animals, however, it was not significantly different from nondiabetic wounds (p ≥ 0.05. Furthermore, epidermal thickness, number of fibroblasts and number of blood vessels were significantly lower in diabetic group (p < 0.05. We concluded that healing of excisional diabetic wounds in sheep may be compromised, as seen in other species. However, contraction rate of these wounds may not be delayed due to metabolic features of ruminants and these animals might go under surgeries without any serious concern. However, healing quality of these wounds may be lower than normal wounds.

  7. Low turnover osteoporosis in sheep induced by hypothalamic-pituitary disconnection.

    Science.gov (United States)

    Beil, Frank Timo; Oheim, Ralf; Barvencik, Florian; Hissnauer, Tim N; Pestka, Jan M; Ignatius, Anita; Rueger, Johannes M; Schinke, Thorsten; Clarke, Iain J; Amling, Michael; Pogoda, Pia

    2012-08-01

    The hypothalamus is of critical importance in regulating bone remodeling. This is underscored by the fact that intracerebroventricular-application of leptin in ewe leads to osteopenia. As a large animal model of osteoporosis, this approach has some limitations, such as high technical expenditure and running costs. Therefore we asked if a surgical ablation of the leptin signaling axis would have the same effects and would thereby be a more useful model. We analyzed the bone phenotype of ewe after surgical hypothalamo-pituitary disconnection (HPD + OVX) as compared to control ewe (OVX) after 3 and 12 months. Analyses included histomorphometric characterization, micro-CT and measurement of bone turnover parameters. Already 3 months after HPD we found osteopenic ewe with a significantly decreased bone formation (69%) and osteoclast activity (49%). After a period of 12 months the HPD group additionally developed an (preclinical) osteoporosis with significant reduction (33%) of femoral cortical thickness, as compared to controls (OVX). Taken together, HPD leads after 12 month to osteoporosis with a reduction in both trabecular and cortical bone caused by a low bone turnover situation, with reduced osteoblast and osteoclast activity, as compared to controls (OVX). The HPD-sheep is a suitable large animal model of osteoporosis. Furthermore our results indicate that an intact hypothalamo-pituitary axis is required for activation of bone turnover.

  8. Local serotonin mediates cyclic strain-induced phenotype transformation, matrix degradation, and glycosaminoglycan synthesis in cultured sheep mitral valves.

    Science.gov (United States)

    Lacerda, Carla M R; Kisiday, John; Johnson, Brennan; Orton, E Christopher

    2012-05-15

    This study addressed the following questions: 1) Does cyclic tensile strain induce protein expression patterns consistent with myxomatous degeneration in mitral valves? 2) Does cyclic strain induce local serotonin synthesis in mitral valves? 3) Are cyclic strain-induced myxomatous protein expression patterns in mitral valves dependent on local serotonin? Cultured sheep mitral valve leaflets were subjected to 0, 10, 20, and 30% cyclic strain for 24 and 72 h. Protein levels of activated myofibroblast phenotype markers, α-smooth muscle actin (α-SMA) and nonmuscle embryonic myosin (SMemb); matrix catabolic enzymes, matrix metalloprotease (MMP) 1 and 13, and cathepsin K; and sulfated glycosaminoglycan (GAG) content in mitral valves increased with increased cyclic strain. Serotonin was present in the serum-free media of cultured mitral valves and concentrations increased with cyclic strain. Expression of the serotonin synthetic enzyme tryptophan hydroxylase 1 (TPH1) increased in strained mitral valves. Pharmacologic inhibition of the serotonin 2B/2C receptor or TPH1 diminished expression of phenotype markers (α-SMA and SMemb) and matrix catabolic enzyme (MMP1, MMP13, and cathepsin K) expression in 10- and 30%-strained mitral valves. These results provide first evidence that mitral valves synthesize serotonin locally. The results further demonstrate that tensile loading modulates local serotonin synthesis, expression of effector proteins associated with mitral valve degeneration, and GAG synthesis. Inhibition of serotonin diminishes strain-mediated protein expression patterns. These findings implicate serotonin and tensile loading in mitral degeneration, functionally link the pathogeneses of serotoninergic (carcinoid, drug-induced) and degenerative mitral valve disease, and have therapeutic implications.

  9. Capsular Polysaccharide is a Main Component of Mycoplasma ovipneumoniae in the Pathogen-Induced Toll-Like Receptor-Mediated Inflammatory Responses in Sheep Airway Epithelial Cells

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    Zhongjia Jiang

    2017-01-01

    Full Text Available Mycoplasma ovipneumoniae (M. ovipneumoniae is characterized as an etiological agent of primary atypical pneumonia that specifically infects sheep and goat. In an attempt to better understand the pathogen-host interaction between the invading M. ovipneumoniae and airway epithelial cells, we investigated the host inflammatory responses against capsular polysaccharide (designated as CPS of M. ovipneumoniae using sheep bronchial epithelial cells cultured in an air-liquid interface (ALI model. Results showed that CPS derived from M. ovipneumoniae could activate toll-like receptor- (TLR- mediated inflammatory responses, along with an elevated expression of nuclear factor kappa B (NF-κB, activator protein-1 (AP-1, and interferon regulatory factor 3 (IRF3 as well as various inflammatory-associated mediators, representatively including proinflammatory cytokines, such as IL1β, TNFα, and IL8, and anti-inflammatory cytokines such as IL10 and TGFβ of TLR signaling cascade. Mechanistically, the CPS-induced inflammation was TLR initiated and was mediated by activations of both MyD88-dependent and MyD88-independent signaling pathways. Of importance, a blockage of CPS with specific antibody led a significant reduction of M. ovipneumoniae-induced inflammatory responses in sheep bronchial epithelial cells. These results suggested that CPS is a key virulent component of M. ovipneumoniae, which may play a crucial role in the inflammatory response induced by M. ovipneumoniae infections.

  10. Phase-transformation-induced twinning of an iron(III) calix[4]pyrrolidine complex.

    Science.gov (United States)

    Journot, Guillaume; Neier, Reinhard; Stoeckli-Evans, Helen

    2014-07-01

    The title compound, tetrachlorido-1κCl;2κ(3)Cl-(2,2,7,7,12,12,17,17-octamethyl-21,22,23,24-tetraazapentacyclo[16.2.1.1(3,6).1(8,11).1(13,16)]tetracosane-1κ(4)N,N',N'',N''')-μ2-oxido-diiron(III), [Fe2Cl4O(C28H52N4)], undergoes a slow phase transformation at ca 173 K from monoclinic space group P2(1)/n, denoted form (I), to the maximal non-isomorphic subgroup, triclinic space group P1, denoted form (II), which is accompanied by nonmerohedral twinning [twin fractions of 0.693 (4) and 0.307 (4)]. The transformation was found to be reversible, as on raising the temperature the crystal reverted to monoclinic form (I). In the asymmetric unit of form (I), Z' = 1, while in form (II), Z' = 2, with a very small reduction (ca 1.8%) in the unit-cell volume. The two independent molecules (A and B) in form (II) are related by a pseudo-twofold screw axis along the b axis. The molecular overlay of molecule A on molecule B has an r.m.s. deviation of 0.353 Å, with the largest distance between two equivalent atoms being 1.202 Å. The reaction of calix[4]pyrrolidine, the fully reduced form of meso-octamethylporphyrinogen, with FeCl3 gave a red-brown solid that was recrystallized from ethanol in air, resulting in the formation of the title compound. In both forms, (I) and (II), the Fe(III) atoms are coordinated to the macrocyclic ligand and have distorted octahedral FeN4OCl coordination spheres. These Fe(III) atoms lie out of the mean plane of the four N atoms, displaced towards the O atom of the [OFeCl3] unit by 0.2265 (5) Å in form (I), and by 0.2210 (14) and 0.2089 (14) Å, respectively, in the two independent molecules (A and B) of form (II). The geometry of the [OFeCl3] units are similar, with each Fe(III) atom having a tetrahedral coordination sphere. The NH H atoms are directed below the planes of the macrocycles and are hydrogen bonded to the coordinated Cl(-) ions. There are also intramolecular C-H···Cl hydrogen bonds present in both (I) and (II

  11. Mifepristone-induced abortion in one horn and a growing fetus in another horn in a patient with a twin pregnancy in a bicornuate uterus.

    Science.gov (United States)

    Chao, Angel; Chao, An-Shine; Wang, Shih-Tíen; Wang, Tzu-Hao

    2006-12-01

    To report a case of mifepristone-induced abortion in only one horn but a growing fetus in another horn for a twin pregnancy in a bicornuate uterus. Case report. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Taiwan. A 31-year-old woman who conceived spontaneously presented with 37 days' gestation. Mifepristone 600 mg orally followed by misoprostol 400 mug orally 2 days later. Termination of pregnancy. Induced abortion in only one horn but a growing fetus in another horn for a twin pregnancy in the bicornuate uterus detected by ultrasound. Surgical abortion with vacuum curettage was performed, and menstruation resumed 1 month later. As medical abortion with mifepristone and misoprostol becomes more prevalent, more studies are necessary to establish the dosage and regimens for multiple pregnancies associated with uterine anomalies.

  12. Twin Baryogenesis

    CERN Document Server

    Farina, Marco; Shin, Chang Sub

    2016-01-01

    In the context of Twin Higgs models, we study a simple mechanism that simultaneously generates asymmetries in the dark and visible sector through the out-of-equilibrium decay of a TeV scale particle charged under a combination of baryon and twin baryon number. We predict the dark matter to be a 5 GeV twin baryon, which is easy to achieve because of the similarity between the two confinement scales. Dark matter is metastable and can decay to three quarks, yielding indirect detection signatures. The mechanism requires the introduction of a new colored particle, typically within the reach of the LHC, of which we study the rich collider phenomenology, including prompt and displaced dijets, multi-jets, monojets and monotops.

  13. Effect of reduction of area on microstructure and mechanical properties of twinning-induced plasticity steel during wire drawing

    Science.gov (United States)

    Hwang, Joong-Ki; Son, Il-Heon; Yoo, Jang-Yong; Zargaran, A.; Kim, Nack J.

    2015-09-01

    The effect of reduction of area (RA), 10%, 20%, and 30%, during wire drawing on the inhomogeneities in microstructure and mechanical properties along the radial direction of Fe-Mn-Al-C twinning-induced plasticity steel has been investigated. After wire drawing, the deformation texture developed into the major and minor duplex fiber texture. However, the texture became more pronounced in both center and surface areas as the RA per pass increased. It also shows that a larger RA per pass resulted in a higher yield strength and smaller elongation than a smaller RA per pass at all strain levels. Although inhomogeneities in microstructure and mechanical properties along the radial direction decreased with increasing RA per pass, there existed an optimum RA per pass for maximum drawing limit. Insufficient penetration of strain from surface to center at small RA per pass (e.g., 10%) and high friction and unsound metal flow at large RA per pass (e.g., 30%) all resulted in heterogeneous microstructure and mechanical properties along the radial direction of drawn wire. On the other hand, 20% RA per pass improved the drawing limit by about 30% as compared to the 10% and 30% RAs per pass.

  14. Role of deformation twins in static recrystallization kinetics of high-purity alpha titanium

    Science.gov (United States)

    Won, Jong Woo; Lee, Taekyung; Hong, Seong-Gu; Lee, Yongmoon; Lee, Jeong Hun; Lee, Chong Soo

    2016-11-01

    The importance of deformation twins in static recrystallization kinetics of high-purity alpha titanium was investigated by carrying out thermal annealing tests of deformed materials in combination with electron-backscatterdiffraction- based microstructural analysis. Prior to thermal annealing, the material was compressed to a true strain of 0.22 along three directions to introduce different twinning characteristics. Our results showed that deformation twins substantially promoted the static recrystallization process by deepening the microstructural inhomogeneity induced by the formation of twin boundaries and twinning-induced crystallographic lattice reorientation. Twin morphology was also observed to be important because it influenced the extent of microstructural inhomogeneity. Intersecting twin morphology, caused by the activation of multiple twin variants, was more effective than parallel twin morphology, caused by the activation of a single twin variant (or a twin variant pair), because it gave rise to more twin boundaries, more twin boundary junctions (intersections, triple junctions, etc.), and greater in-grain crystallographic orientation spread.

  15. Hypertensive disorders in twin pregnancy

    OpenAIRE

    Santema, Job; Koppelaar, Elin; Wallenburg, Henk

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending the antenatal clinic and booked before a gestational age of 24 weeks was matched for maternal age, parity, and gestational age at delivery with a singleton pregnancy delivered in the same year. Prima...

  16. Immune responses in rats and sheep induced by a DNA vaccine containing the phosphoglycerate kinase gene of Fasciola hepatica and liver fluke infection.

    Science.gov (United States)

    Wesołowska, Agnieszka; Zawistowska-Deniziak, Anna; Norbury, Luke J; Wilkowski, Przemysław; Januszkiewicz, Kamil; Pyziel, Anna M; Zygner, Wojciech; Wędrychowicz, Halina

    2016-03-01

    Immune responses of rats and sheep following vaccination with cDNA encoding phosphoglycerate kinase of Fasciola hepatica (cDNA-FhPGK/pCMV) and F. hepatica infection were investigated in the present study. cDNA-FhPGK/pCMV vaccinated female Sprague-Dawley rats were better protected by vaccination than their male counterparts - 48% reduction in fluke burden for females and no protection for males when compared with appropriate infection control groups. Moreover, male rats developed marked leukocytosis during the study with higher neutrophil, eosinophil and monocyte responses than females. Additionally, dynamics of eosinophil and monocyte responses varied between sexes. Increased titres of anti-FhPGK IgG1 and IgG2a correlated with the protective effect of vaccination that was observed among female rats. In the case of male sheep, no differences in worm burdens and in the course of the immune response were observed following vaccination. Titres of specific antibodies detected were low, and cellular responses were not significant. Apparently, sheep immune responses induced by cDNA-FhPGK/pCMV vaccination are not effective at controlling F. hepatica infection. Poor immunogenicity of DNA vaccines in large animals is still a major obstacle of this technology that has to be overcome.

  17. Endotoxin-induced maturation of monocytes in preterm fetal sheep lung.

    Science.gov (United States)

    Kramer, Boris W; Joshi, Shubhada N; Moss, Timothy J M; Newnham, John P; Sindelar, Richard; Jobe, Alan H; Kallapur, Suhas G

    2007-08-01

    The fetal lung normally contains immature monocytes and very few mature macrophages. The chorioamnionitis frequently associated with preterm birth induces monocyte influx into the fetal lung. Previous studies demonstrated that monocytes in the developing lung can mediate lung injury responses that resemble BPD in humans. We hypothesized that chorioamnionitis would induce maturation of immature monocytes in the fetal lung. Groups of three to seven time-mated ewes received saline or 10 mg of endotoxin (Escherichia coli 055:B5) in saline by intra-amniotic injection for intervals from 1 to 14 days before operative delivery at 124 days of gestational age. Monocytic cells from lung tissue were recovered using Percoll gradients. Monocytic cells consistent with macrophages were identified morphologically and by myosin heavy chain class II expression. An increase in macrophages was preceded by induction of granulocyte-macrophage colony-stimulating factor in the lung and subsequent activation of the transcription factor PU.1. The production of IL-6 by monocytes/macrophages in response to endotoxin challenge in vitro increased 7 and 14 days after exposure to intra-amniotic endotoxin. Recombinant TNF-alpha induced IL-6 production by lung monocytic cells exposed to intra-amniotic endotoxin but not in control cells. Monocytic phagocytosis of apoptotic neutrophils also increased 7 and 14 days after exposure to intra-amniotic endotoxin. Intra-amniotic endotoxin induced lung monocytes to develop into functionally mature cells consistent with macrophages. These findings have implications for lung immune responses after exposure to chorioamnionitis.

  18. Growth Twinning and Generation of High-Frequency Surface Nanostructures in Ultrafast Laser-Induced Transient Melting and Resolidification.

    Science.gov (United States)

    Sedao, Xxx; Shugaev, Maxim V; Wu, Chengping; Douillard, Thierry; Esnouf, Claude; Maurice, Claire; Reynaud, Stéphanie; Pigeon, Florent; Garrelie, Florence; Zhigilei, Leonid V; Colombier, Jean-Philippe

    2016-07-26

    The structural changes generated in surface regions of single crystal Ni targets by femtosecond laser irradiation are investigated experimentally and computationally for laser fluences that, in the multipulse irradiation regime, produce sub-100 nm high spatial frequency surface structures. Detailed experimental characterization of the irradiated targets combining electron back scattered diffraction analysis with high-resolution transmission electron microscopy reveals the presence of multiple nanoscale twinned domains in the irradiated surface regions of single crystal targets with (111) surface orientation. Atomistic- and continuum-level simulations performed for experimental irradiation conditions reproduce the generation of twinned domains and establish the conditions leading to the formation of growth twin boundaries in the course of the fast transient melting and epitaxial regrowth of the surface regions of the irradiated targets. The observation of growth twins in the irradiated Ni(111) targets provides strong evidence of the role of surface melting and resolidification in the formation of high spatial frequency surface structures. This also suggests that the formation of twinned domains can be used as a sensitive measure of the levels of liquid undercooling achieved in short pulse laser processing of metals.

  19. Antenatal and postnatal corticosteroid and resuscitation induced lung injury in preterm sheep

    Directory of Open Access Journals (Sweden)

    Kallapur Suhas G

    2009-12-01

    Full Text Available Abstract Background Initiation of ventilation using high tidal volumes in preterm lambs causes lung injury and inflammation. Antenatal corticosteroids mature the lungs of preterm infants and postnatal corticosteroids are used to treat bronchopulmonary dysplasia. Objective To test if antenatal or postnatal corticosteroids would decrease resuscitation induced lung injury. Methods 129 d gestational age lambs (n = 5-8/gp; term = 150 d were operatively delivered and ventilated after exposure to either 1 no medication, 2 antenatal maternal IM Betamethasone 0.5 mg/kg 24 h prior to delivery, 3 0.5 mg/kg Dexamethasone IV at delivery or 4 Cortisol 2 mg/kg IV at delivery. Lambs then were ventilated with no PEEP and escalating tidal volumes (VT to 15 mL/kg for 15 min and then given surfactant. The lambs were ventilated with VT 8 mL/kg and PEEP 5 cmH20 for 2 h 45 min. Results High VT ventilation caused a deterioration of lung physiology, lung inflammation and injury. Antenatal betamethasone improved ventilation, decreased inflammatory cytokine mRNA expression and alveolar protein leak, but did not prevent neutrophil influx. Postnatal dexamethasone decreased pro-inflammatory cytokine expression, but had no beneficial effect on ventilation, and postnatal cortisol had no effect. Ventilation increased liver serum amyloid mRNA expression, which was unaffected by corticosteroids. Conclusions Antenatal betamethasone decreased lung injury without decreasing lung inflammatory cells or systemic acute phase responses. Postnatal dexamethasone or cortisol, at the doses tested, did not have important effects on lung function or injury, suggesting that corticosteroids given at birth will not decrease resuscitation mediated injury.

  20. Beam induced heat loads on the beam-screens of the twin-bore magnets in the IRs of the HL-LHC

    CERN Document Server

    Iadarola, Giovanni; Rumolo, Giovanni

    2016-01-01

    The expected heat load induced on the beam screens has been evaluated for all the twin-bore magnets in the Insertion Regions (IRs) of the HL-LHC. The contribution from the impedance of the beam screen has been evaluated taking into account the presence of a longitudinal weld in the beam screen and the impact of the temperature and of the magnetic field on the resistivity of the surface. The contribution coming from electron cloud effects has been evaluated for different values of the Secondary Electron Yield of the surface based PyECLOUD build-up simulations.

  1. Response to dietary-induced energy restriction in dairy sheep divergently selected for resistance or susceptibility to mastitis.

    Science.gov (United States)

    Bouvier-Muller, J; Allain, C; Enjalbert, F; Tabouret, G; Portes, D; Caubet, C; Tasca, C; Foucras, G; Rupp, R

    2016-01-01

    Dairy ruminants experiencing a severe postpartum negative energy balance (NEB) are considered to be more susceptible to mastitis. Although the genetic variability of mastitis resistance is well established, the biological basis of the link between energy metabolism and resistance is mostly unknown. The aim of this study was to characterize the effect of NEB on metabolism and immune response according to the genetic background for mastitis resistance or susceptibility. Forty-eight ewes from high and low somatic cell score (SCS) genetic lines were allocated to 2 homogeneous subgroups 2 wk after lambing: one group (NEB) received an energy-restricted diet to cover 60% of their energy requirements, and the other group received a control (positive energy balance: PEB) diet. Both diets met the protein requirements. After 10 d on either the NEB or PEB diet, all ewes were injected with a Pam3CSK4/MDP solution in one half-udder to induce an inflammatory response. The ewes were monitored for milk production, somatic cell count (SCC), body weight (BW), body condition score (BCS), and blood metabolites. Differential milk cell counts were determined by flow cytometry. Plasma concentrations of glucose, insulin, nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHB), and triiodothyronine were determined. Energy restriction resulted in an increased fat:protein ratio in milk and decreased milk yield, BW, and BCS. The NEB ewes had significantly higher NEFA and BHB and lower plasma glucose concentrations than PEB ewes, reflecting a mobilization of body reserves and ketone body synthesis. High-SCS ewes had a higher SCS than low-SCS throughout the experiment, except after the inflammatory challenge, which resulted in similar SCS in all 4 groups. A noteworthy interaction between genetic background and diet was evidenced on metabolic parameters and BW. Indeed, high-SCS ewes subjected to NEB showed greater decrease in BW and increased NEFA and BHB concentrations compared with low

  2. Frequent extreme cold exposure and brown fat and cold-induced thermogenesis: a study in a monozygotic twin.

    Directory of Open Access Journals (Sweden)

    Maarten J Vosselman

    Full Text Available INTRODUCTION: Mild cold acclimation is known to increase brown adipose tissue (BAT activity and cold-induced thermogenesis (CIT in humans. We here tested the effect of a lifestyle with frequent exposure to extreme cold on BAT and CIT in a Dutch man known as 'the Iceman', who has multiple world records in withstanding extreme cold challenges. Furthermore, his monozygotic twin brother who has a 'normal' sedentary lifestyle without extreme cold exposures was measured. METHODS: The Iceman (subject A and his brother (subject B were studied during mild cold (13°C and thermoneutral conditions (31°C. Measurements included BAT activity and respiratory muscle activity by [18F]FDG-PET/CT imaging and energy expenditure through indirect calorimetry. In addition, body temperatures, cardiovascular parameters, skin perfusion, and thermal sensation and comfort were measured. Finally, we determined polymorphisms for uncoupling protein-1 and β3-adrenergic receptor. RESULTS: Subjects had comparable BAT activity (A: 1144 SUVtotal and B: 1325 SUVtotal, within the range previously observed in young adult men. They were genotyped with the polymorphism for uncoupling protein-1 (G/G. CIT was relatively high (A: 40.1% and B: 41.9%, but unlike during our previous cold exposure tests in young adult men, here both subjects practiced a g-Tummo like breathing technique, which involves vigorous respiratory muscle activity. This was confirmed by high [18F]FDG-uptake in respiratory muscle. CONCLUSION: No significant differences were found between the two subjects, indicating that a lifestyle with frequent exposures to extreme cold does not seem to affect BAT activity and CIT. In both subjects, BAT was not higher compared to earlier observations, whereas CIT was very high, suggesting that g-Tummo like breathing during cold exposure may cause additional heat production by vigorous isometric respiratory muscle contraction. The results must be interpreted with caution given the

  3. Individual susceptibility to DNA telomerase inhibitors: a study on the chromosome instability induced by 3'-azido-3'-deoxythymidine in lymphocytes of elderly twins.

    Science.gov (United States)

    Caporossi, Daniela; Argentin, Gabriella; Pittaluga, Monica; Parisi, Paolo; Tedeschi, Bruna; Vernole, Patrizia; Cicchetti, Rosadele

    2004-03-01

    The activation of telomerase in phytohemagglutinin-stimulated peripheral lymphocytes is thought to play a role in telomere maintenance and DNA repair. Considering the importance of this enzyme in both cancer and senescence, we studied the effects of the telomerase inhibitor 3'-azido-3'-deoxythymidine on the frequency of chromosomal aberrations and micronuclei induced in peripheral blood lymphocytes (PBL) of elderly monozygotic and dizygotic twins, evaluated with respect to the genotoxic effects induced in unrelated young subjects. Our results show that the cytogenetic damage induced by 3'-azido-3'-deoxythymidine in human PBL was mainly regulated by genetic factors and allowed the identification of hypersensitive subjects. Ageing, which did not modify the individual susceptibility to 3'-azido-3'-deoxythymidine induction of chromosome aberrations and micronuclei, nevertheless determined an overall increase in nuclear damage.

  4. Meconium fatty acid ethyl esters as biomarkers of late gestational ethanol exposure and indicator of ethanol-induced multi-organ injury in fetal sheep.

    Directory of Open Access Journals (Sweden)

    Irene Zelner

    Full Text Available BACKGROUND: Meconium fatty acid ethyl esters (FAEE constitute a biomarker of heavy fetal ethanol exposure. Our objective was to measure meconium FAEE in fetal sheep following daily, relatively moderate-dose ethanol exposure in late gestation, and to evaluate their utility in identifying fetal organ-system injury. METHODS: Pregnant ewes received ethanol (0.75 g/kg; n = 14 or saline (n = 8 via 1-h i.v. infusion daily during the third trimester equivalent, while additional pregnant sheep served as untreated controls (n = 6. The daily ethanol regimen produced similar maximal maternal and fetal plasma ethanol concentrations of 0.11-0.12 g/dL. Ewes and fetuses were euthanized shortly before term, and meconium was collected and analyzed for FAEE (ethyl palmitate, stearate, linoleate, and oleate. RESULTS: Meconium total FAEE concentration was significantly higher in ethanol-exposed fetuses compared with controls, and a positive cut-off of 0.0285 nmol total FAEE/g meconium had 93.3% sensitivity and specificity for detecting fetal ethanol exposure. When the studied animals (ethanol-exposed and controls were classified according to meconium FAEE concentration, FAEE-positive and FAEE-negative groups frequently differed with respect to previously examined pathological endpoints, including nephron endowment, lung collagen deposition, cardiomyocyte maturation, and tropoelastin gene expression in cerebral vessels. Furthermore, in all studied animals as a group (ethanol-exposed and controls combined, meconium FAEE concentration was correlated with many of these pathological endpoints in fetal organs. CONCLUSIONS: We conclude that, in fetal sheep, meconium FAEE could serve as a biomarker of daily ethanol exposure in late gestation and could identify fetuses with subtle ethanol-induced toxic effects in various organs. This study illustrates the potential for using meconium FAEE to identify neonates at risk for dysfunction of major organs following in

  5. The Qingdao Twin Registry

    DEFF Research Database (Denmark)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng;

    2013-01-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants...... of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes...

  6. A Study on Genes of Bayanbulak Sheep

    Directory of Open Access Journals (Sweden)

    Beiyao Zuo

    2013-01-01

    Full Text Available The average twin lambing rate of Bayanbulak sheep is 2% to 3%. However, a flock of sheep with a close genetic relationship and an average of 2 to 3 lambs per birth has been found recently. To determine the major genes controlling the prolificacy of the flock in the present study, the flock was designated A while 100 normal Bayanbulak sheep were randomly selected to comprise the control flock B. Ligase detection reaction method was applied to detect and analyze the 10 mutational loci of the 3 candidate prolificacy genes including bone morphogenetic protein type I receptors, bone morphogenetic protein 15, and growth differentiation factor 9. The 10 mutational loci are as follows: FecB locus of the BMPR-IB gene; FecXI, FecXB, FecXL, FecXH, FecXG, and FecXR of the BMP15 gene; and G1, G8, and FecTT of the GDF9 gene. Two mutations including BMPR-IB/FecB and GDF9/G1 were found in Bayanbulak sheep. Independence test results of the two flocks demonstrate that the FecB locus has a significant effect on the lambing number of Bayanbulak sheep. However, the mutation frequency of the G1 locus in GDF9 is very low. Independence test results demonstrate that the GDF9 locus does not have a significant impact on the lambing performance of Bayanbulak sheep. Among the 10 detected loci, BMPR-IB/FecB is the major gene that influences the high lambing rate of Bayanbulak sheep.

  7. Twin Jet

    Science.gov (United States)

    Henderson, Brenda; Bozak, Rick

    2010-01-01

    Many subsonic and supersonic vehicles in the current fleet have multiple engines mounted near one another. Some future vehicle concepts may use innovative propulsion systems such as distributed propulsion which will result in multiple jets mounted in close proximity. Engine configurations with multiple jets have the ability to exploit jet-by-jet shielding which may significantly reduce noise. Jet-by-jet shielding is the ability of one jet to shield noise that is emitted by another jet. The sensitivity of jet-by-jet shielding to jet spacing and simulated flight stream Mach number are not well understood. The current experiment investigates the impact of jet spacing, jet operating condition, and flight stream Mach number on the noise radiated from subsonic and supersonic twin jets.

  8. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  9. Deformation twinning in monazite

    Energy Technology Data Exchange (ETDEWEB)

    Hay, R.S.; Marshall, D.B

    2003-10-20

    Polycrystalline monazite (LaPO{sub 4}) was deformed at room temperature by a spherical indenter. Deformation twins were identified by TEM in 70 grains. Five twin planes were found: (100) was by far the most common; (001) and (120) were less common; (122-bar)was rare, and kinks in (120) twins were identified as irrational '(483)' twin planes. The twinning modes on these planes were inferred from the expression of twinning shear at free surfaces, predictions of classical deformation twinning theory, and various considerations of twin morphology and crystal structure. Atomic shuffle calculations that allow formation of either a glide plane or a mirror plane at the twin interface were used to analyze twin modes. The inferred twin modes all have small atomic shuffles. For (001) twins, the smallest shuffles were obtained with a glide plane at the interface, with displacement vector R=((1)/(2))[010]. The results do not uniquely define a twin mode on (100), leaving open the possibility of more than one mode operating on this plane. Factors that may determine the operative deformation twinning modes are discussed. Crystal structure considerations suggest that the relative abundance of twinning modes may correlate with low shear modulus on the twin plane in the direction of twinning shear, and with a possible low-energy interface structure consisting of a layer of xenotime of one half-unit-cell thickness that could form at (100) and (001) twins. The three most common twins have low strains to low {sigma} coincidence site lattices (CSLs)

  10. Experimental infection by Trypanosoma evansi in sheep: Occurrence of transplacental transmission and mice infection by parasite present in the colostrum and milk of infected ewes.

    Science.gov (United States)

    Campigotto, Gabriela; Da Silva, Aleksandro S; Volpato, Andreia; Balzan, Alexandre; Radavelli, Willian M; Soldá, Natan M; Grosskopf, Hyolanda M; Stefani, Lenita M; Bianchi, Anderson E; Monteiro, Silvia G; Tonin, Alexandre A; Weiss, Paulo H E; Miletti, Luiz C; Lopes, Sonia T A

    2015-09-15

    The aims of this study were to evaluate vertical transmission of Trypanosoma evansi in sheep experimentally infected, in addition to the mammary transmission by colostrum or milk of these infected sheep to mice. Three pregnant sheep were used: one uninfected, four months pregnant (Sheep A); and two (Sheep B and C) infected intravenously by T. evansi trypomastigotes (4.6×10(6) per animal) on the third (Sheep C) and fourth (Sheep B) month of pregnancy. Both infected sheep developed low and oscillating parasitemia measured by blood smears. Hemogram was performed at seven day intervals, showing anemia, leukocytosis, and lymphocytosis on sheep B and C. Three sheep had twins, where sheep A delivered healthy lambs and both infected sheep had delivered at least one stillborn. Additionally, lambs from sheep B and C died 24 and 72 h post-partum, respectively. Before colostrum intake, four lambs from infected sheep were positives for T. evansi according to blood smear evaluation, serology (CATT/T. evansi), and PCR. Sheep colostrum and milk samples collected from the first four days post-partum were positives for T. evansi on PCR, and these samples were able to infect seven mice (out of 10) orally (n=4/5) and intraperitoneally (n=3/5). Therefore, we conclude that the vertical transmission of T. evansi occurs in pregnant sheep, in addition to a strong possibility of the transmission by colostrum and milk.

  11. Serum and colostrum antibody responses induced by jet-injection of sheep with DNA encoding a Cryptosporidium parvum antigen.

    Science.gov (United States)

    Jenkins, M; Kerr, D; Fayer, R; Wall, R

    1995-12-01

    In an effort to generate high titer colostrum for immunotherapy of cryptosporidiosis, a study was conducted to test the efficacy of immunizing sheep with recombinant plasmid DNA (pCMV-CP15/60) encoding epitopes of 15 and 60 kDa surface antigens of Cryptosporidium parvum sporozoites. The plasmid DNA was used to immunize preparturient ewes at three dose levels by jet-injection into either hind limb muscle (IM) or mammary tissue (IMAM). Regardless of route of injection, a dose-dependent anti-CP15/60 immunoglobulin response was observed in sera and colostrum from sheep immunized with pCMV-CP15/60 plasmid DNA. High titer antibody responses were observed in one of three animals per group receiving an IM injection of 100 or 1000 micrograms pCMV-CP15/60. IMAM immunization with 100 or 1000 micrograms pCMV-CP15/60 plasmid DNA elicited higher titer colostrum responses and more consistent serum responses compared to IM injections. A negligible serum and colostrum anti-CP15/60 response was observed in ewes injected IM with 10 micrograms pCMV-CP15/60 or 1000 micrograms control plasmid DNA. Immunoblotting of native C. parvum sporozoite/oocyst protein with hyperimmune serum and colostrum corroborated the increased titers against CP15/60 antigen. Serum and colostrum antibodies from pCMV-CP15/60-immunized sheep were eluted from native CP15 protein and bound a surface antigen of C. parvum sporozoites as indicated by indirect immunofluorescence staining.

  12. The Norwegian Twin Registry.

    Science.gov (United States)

    Nilsen, Thomas S; Brandt, Ingunn; Magnus, Per; Harris, Jennifer R

    2012-12-01

    Norway has a long-standing tradition in twin research, but the data collected in several population-based twin studies were not coordinated centrally or easily accessible to the scientific community. In 2009, the Norwegian Twin Registry was established at the Norwegian Institute of Public Health (NIPH) in Oslo with the purpose of creating a single research resource for Norwegian twin data. As of today, the Norwegian Twin Registry contains 47,989 twins covering birth years 1895-1960 and 1967-1979; 31,440 of these twins consented to participate in health-related research. In addition, DNA from approximately 4,800 of the twins is banked at the NIPH biobank and new studies are continually adding new data to the registry. The value of the Norwegian twin data is greatly enhanced by the linkage opportunities offered by Norway's many nationwide registries, spanning a broad array of medical, demographic, and socioeconomic information.

  13. An in-situ neutron diffraction study of a multi-phase transformation and twinning-induced plasticity steel during cyclic loading

    Energy Technology Data Exchange (ETDEWEB)

    Saleh, Ahmed A., E-mail: asaleh@uow.edu.au [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, New South Wales 2522 (Australia); Brown, Donald W.; Clausen, Bjørn; Tomé, Carlos N. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Pereloma, Elena V. [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, New South Wales 2522 (Australia); Electron Microscopy Centre, University of Wollongong, Wollongong, New South Wales 2500 (Australia); Davies, Christopher H. J. [Department of Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800 (Australia); Gazder, Azdiar A. [Electron Microscopy Centre, University of Wollongong, Wollongong, New South Wales 2500 (Australia)

    2015-04-27

    In-situ neutron diffraction during cyclic tension-compression loading (∼+3.5% to −2.8%) of a 17Mn-3Al-2Si-1Ni-0.06C steel that exhibits concurrent transformation and twinning -induced plasticity effects indicated a significant contribution of intragranular back stresses to the observed Bauschinger effect. Rietveld analysis revealed a higher rate of martensitic transformation during tension compared to compression. Throughout cycling, α′-martensite exhibited the highest phase strains such that it bears an increasing portion of the macroscopic load as its weight fraction evolves. On the other hand, the ε-martensite strain remained compressive as it accommodated most of the internal strains caused by the shape misfit associated with the γ→ε and/or ε→α′ transformations.

  14. Paroxysmal exercise-induced dyskinesia, writer's cramp, migraine with aura and absence epilepsy in twin brothers with a novel SLC2A1 missense mutation.

    Science.gov (United States)

    Urbizu, Aintzane; Cuenca-León, Ester; Raspall-Chaure, Miquel; Gratacòs, Margarida; Conill, Joan; Redecillas, Susana; Roig-Quilis, Manuel; Macaya, Alfons

    2010-08-15

    We report two monochorionic twins that progressively developed, between ages 5 and 10, a combination of episodic neurological disorders including paroxysmal exercise-induced dyskinesia, migraine without or with aura, absence seizures and writer's cramp. CSF/serum glucose ratio was moderately decreased in both patients. Mutational analysis of SLC2A1 gene identified a de novo heterozygous missense mutation in exon 4. This novel mutation has been previously showed to disrupt glucose transport in vitro. Both patients showed immediate and near-complete response to ketogenic diet. This clinical observation suggests that a high index of suspicion for GLUT1 deficiency syndrome is warranted in evaluating patients with multiple neurological paroxysmal events.

  15. The Danish Twin Register

    DEFF Research Database (Denmark)

    Kyvik, K O; Christensen, Kaare; Skytthe, A;

    1996-01-01

    BACKGROUND: Population based twin registers represent a valuable tool for genetic epidemiological research, since twin studies aim at separating the effect of genes and environment for complex traits. The Danish Twin Register's history, size, ascertainment and completeness of data, as well as data...... accessibility and availability are described. RESULTS: The Danish Twin Register comprises 14,051 twin pairs born 1870-1930, representing all twins surviving to age six years, and 20,888 twin pairs born 1953-1982, representing 75% of those born 1953-1967 and 95% of those born 1968-1982. The birth cohorts 1931......-1952 og 1983-1993 are being ascertained at the moment. The register is available for research given certain conditions are fulfilled. CONCLUSION: This register will in a few years be the most comprehensive twin register in the world. It is a very valuable Danish research resource....

  16. The Danish Twin Register

    DEFF Research Database (Denmark)

    Kyvik, K O; Christensen, Kaare; Skytthe, A

    1996-01-01

    BACKGROUND: Population based twin registers represent a valuable tool for genetic epidemiological research, since twin studies aim at separating the effect of genes and environment for complex traits. The Danish Twin Register's history, size, ascertainment and completeness of data, as well as data...... accessibility and availability are described. RESULTS: The Danish Twin Register comprises 14,051 twin pairs born 1870-1930, representing all twins surviving to age six years, and 20,888 twin pairs born 1953-1982, representing 75% of those born 1953-1967 and 95% of those born 1968-1982. The birth cohorts 1931......-1952 og 1983-1993 are being ascertained at the moment. The register is available for research given certain conditions are fulfilled. CONCLUSION: This register will in a few years be the most comprehensive twin register in the world. It is a very valuable Danish research resource....

  17. Foreign body-induced changes in the reticular contraction pattern of sheep observed with M-mode ultrasonography

    Science.gov (United States)

    Morgado, A.A.; Sucupira, M.C.A.; Nunes, G.R.; Hagen, S.C.F.

    2015-01-01

    In the pre-experimental period of a clinical trial, an apparently clinically healthy sheep fitted with ruminal and abomasal cannulas showed changes in the reticular contraction pattern visualized in M-mode ultrasonogram. Radiographic examination revealed a blunt metal screw in its reticulum. By the time change in the reticular motility through the ultrasound examination was detected, the animal had still not expressed any behavioral changes. A description of the clinical case, follow-up of the findings and laboratory data, like white blood cell count, serum pepsinogen and fibrinogen concentrations, were presented. The foreign body was removed through the ruminal cannula and reticular contraction tended to normal. An association of the contraction pattern with measured clinical data was possible, leading to the conclusion that use of M-mode ultrasonography has a potential application in similar clinical situations. PMID:26623361

  18. Foreign body-induced changes in the reticular contraction pattern of sheep observed with M-mode ultrasonography

    Directory of Open Access Journals (Sweden)

    A.A. Morgado

    2015-04-01

    Full Text Available In the pre-experimental period of a clinical trial, an apparently clinically healthy sheep fitted with ruminal and abomasal cannulas showed changes in the reticular contraction pattern visualized in M-mode ultrasonogram. Radiographic examination revealed a blunt metal screw in its reticulum. By the time change in the reticular motility through the ultrasound examination was detected, the animal had still not expressed any behavioral changes. A description of the clinical case, follow-up of the findings and laboratory data, like white blood cell count, serum pepsinogen and fibrinogen concentrations, were presented. The foreign body was removed through the ruminal cannula and reticular contraction tended to normal. An association of the contraction pattern with measured clinical data was possible, leading to the conclusion that use of M-mode ultrasonography has a potential application in similar clinical situations.

  19. Plasticity and ultra-low stress induced twin boundary migration in nanotwinned Cu by in situ nanoindentation studies

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y.; Chen, Y. [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Jian, J. [Department of Electrical Engineering, Texas A and M University, College Station, Texas 77843 (United States); Wang, H. [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Department of Electrical Engineering, Texas A and M University, College Station, Texas 77843 (United States); Zhang, X., E-mail: zhangx@tamu.edu [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843 (United States)

    2014-06-09

    Nanotwinned metals have rare combinations of mechanical strength and ductility. Previous studies have shown that detwinning occurs in plastically deformed nanotwinned metals. Although molecular dynamics simulations have predicted that fine nanotwins can migrate at low stress, there is little in situ evidence to validate such predictions. Also it is unclear if detwinning occurs prior to or succeeding plastic yielding. Here, by using in situ nanoindentation in a transmission electron microscope, we show that a non-elastic detwinning process in nanotwinned Cu occurred at ultra-low indentation stress (0.1 GPa), well before the stress necessary for plastic yielding. Furthermore, the in situ nanoindentation technique allows us to differentiate dislocation-nucleation dominated microscopic yielding preceding macroscopic yielding manifested by dislocation-transmission through twin boundaries. This study thus provides further insights for understanding plasticity in nanotwinned metals at microscopic levels.

  20. Serration Phenomena Occurring During Tensile Tests of Three High-Manganese Twinning-Induced Plasticity (TWIP) Steels

    Science.gov (United States)

    Hong, Seokmin; Shin, Sang Yong; Lee, Junghoon; Ahn, Dong-Hyun; Kim, Hyoung Seop; Kim, Sung-Kyu; Chin, Kwang-Geun; Lee, Sunghak

    2014-02-01

    In this study, the serration phenomena of two high-Mn TWIP steels and an Al-added TWIP steel were examined by tensile tests, and were explained by the microstructural evolution including formation of localized Portevin-Le Chatelier deformation bands and twins. In stress-strain curves of the high-Mn steels, serrations started in a fine and short shape, and their height and periodic interval increased with increasing strain, whereas the Al-added steel did not show any serrations. According to digital images of strain rate and strain obtained from a vision strain gage system, deformation bands were initially formed at the upper region of the gage section, and moved downward along the tensile loading direction. The time when the band formation started was matched with the time when one serration occurred in the stress-time curve. This serration behavior was generally explained by dynamic strain aging, which was closely related with the formation of deformation bands.

  1. Monochorionic twin pregnancies

    NARCIS (Netherlands)

    Hack, K.E.A.

    2008-01-01

    Following widespread application of assisted reproductive technology modalities and the increased age of motherhood, the incidence of twin gestations has increased markedly. Twins are either monozygotic or dizygotic. Dizygotic (i.e. fraternal) twins result from the fertilization of two different egg

  2. Glide twinning and pseudotwinning in peristerite: twin morphology and propagation

    Science.gov (United States)

    Brown, William L.

    1989-07-01

    Optically visible Albite glide “twins” in a peristerite (˜An9Or1.6), identified from their tapering shape and relationship to grain boundaries, were studied by transmission electron microscopy. Near the tips in sections ⊥ a, the microstructure consists of small (˜400 nm long) lensshaped Albite twins centred exclusively on the oligoclase lamellae. The lenses extend partly outwards into the two adjacent low albite lamellae and induce strong inhomogeneous strain. Where the lenses are closer together, they form, depending on the sense of shear, nearly linear left or right-stepping en échelon arrays, with overlap of the strain fields. Slightly farther in from the tip, the twin domains coalesce to form continuous pinch-and-swell lamellae, being always thicker in the oligoclase. Because of Si,Al order, only elastic glide pseudotwins are possible in low albite. In oligoclase glide pseudotwins may be mechanically stable (metastable relative to Si,Al order) and may deviate only slightly from true twins. Pseudotwins develop first in the oligoclase, propagate dynamically by jumping across the intervening albite lamellae, extend lengthways and thicken sideways and finally coalesce. They are stabilized by diffusion-controlled inversion of Si,Al order giving rise to true twins described in a companion paper.

  3. Two outer membrane lipoproteins from Histophilus somni are immunogenic in rabbits and sheep and induce protection against bacterial challenge in mice.

    Science.gov (United States)

    Guzmán-Brambila, Carolina; Rojas-Mayorquín, Argelia E; Flores-Samaniego, Beatriz; Ortuño-Sahagún, Daniel

    2012-11-01

    Histophilus somni is an economically important pathogen of cattle and other ruminants and is considered one of the key components of the bovine respiratory disease (BRD) complex, the leading cause of economic loss in the livestock industry. BRD is a multifactorial syndrome, in which a triad of agents, including bacteria, viruses, and predisposing factors or "stressors," combines to induce disease. Although vaccines against H. somni have been used for many decades, traditional bacterins have failed to demonstrate effective protection in vaccinated animals. Hence, the BRD complex continues to produce strong adverse effects on the health and well-being of stock and feeder cattle. The generation of recombinant proteins may facilitate the development of more effective vaccines against H. somni, which could confer better protection against BRD. In the present study, primers were designed to amplify, clone, express, and purify two recombinant lipoproteins from H. somni, p31 (Plp4) and p40 (LppB), which are structural proteins of the outer bacterial membrane. The results presented here demonstrate, to our knowledge for the first time, that when formulated, an experimental vaccine enriched with these two recombinant lipoproteins generates high antibody titers in rabbits and sheep and exerts a protective effect in mice against septicemia induced by H. somni bacterial challenge.

  4. Genetic components of litter size variability in sheep

    Directory of Open Access Journals (Sweden)

    Chevalet Claude

    2001-05-01

    Full Text Available Abstract Classical selection for increasing prolificacy in sheep leads to a concomitant increase in its variability, even though the objective of the breeder is to maximise the frequency of an intermediate litter size rather than the frequency of high litter sizes. For instance, in the Lacaune sheep breed raised in semi-intensive conditions, ewes lambing twins represent the economic optimum. Data for this breed, obtained from the national recording scheme, were analysed. Variance components were estimated in an infinitesimal model involving genes controlling the mean level as well as its environmental variability. Large heritability was found for the mean prolificacy, but a high potential for increasing the percentage of twins at lambing while reducing the environmental variability of prolificacy is also suspected. Quantification of the response to such a canalising selection was achieved.

  5. Genetic components of litter size variability in sheep

    Science.gov (United States)

    SanCristobal-Gaudy, Magali; Bodin, Loys; Elsen, Jean-Michel; Chevalet, Claude

    2001-01-01

    Classical selection for increasing prolificacy in sheep leads to a concomitant increase in its variability, even though the objective of the breeder is to maximise the frequency of an intermediate litter size rather than the frequency of high litter sizes. For instance, in the Lacaune sheep breed raised in semi-intensive conditions, ewes lambing twins represent the economic optimum. Data for this breed, obtained from the national recording scheme, were analysed. Variance components were estimated in an infinitesimal model involving genes controlling the mean level as well as its environmental variability. Large heritability was found for the mean prolificacy, but a high potential for increasing the percentage of twins at lambing while reducing the environmental variability of prolificacy is also suspected. Quantification of the response to such a canalising selection was achieved. PMID:11403747

  6. Differential Susceptibility of Bighorn Sheep (Ovis canadensis) and Domestic Sheep (Ovis aries) Neutrophils to Mannheimia haemolytica Leukotoxin is not due to Differential Expression of Cell Surface CD18.

    Science.gov (United States)

    Dassanayake, Rohana P; Shanthalingam, Sudarvili; Liu, Weiguo; Casas, Eduardo; Srikumaran, Subramaniam

    2017-07-01

    Bighornsheep ( Ovis canadensis ) are more susceptible to pneumonia caused by Mannheimia haemolytica than are domestic sheep ( Ovis aries ). Leukotoxin produced by M. haemolytica is the principal virulence factor involved in pneumonia pathogenesis. Although leukotoxin is cytolytic to all subsets of ruminant leukocytes, neutrophils are the most susceptible subset. Bighorn sheep neutrophils are four- to eightfold more susceptible to leukotoxin-induced cytolysis than are domestic sheep neutrophils. We hypothesized that the higher susceptibility of bighorn sheep neutrophils, in comparison to domestic sheep neutrophils, is due to higher expression of CD18, the receptor for leukotoxin on leukocytes. Our objective was to quantify CD18 expression on neutrophils of bighorn sheep and domestic sheep. Cell-surface CD18 expression on bighorn sheep and domestic sheep neutrophils was measured as antibody binding capacity of cells by flow cytometric analysis with two fluorochrome-conjugated anti-CD18 monoclonal antibodies (BAQ30A and HUH82A) and microspheres. Contrary to our expectations, CD18 expression was higher (Psheep neutrophils in comparison to bighorn sheep neutrophils. These findings suggest that the higher in vitro susceptibility to leukotoxin of bighorn sheep neutrophils compared to domestic sheep neutrophils is not due to higher expression of the leukotoxin receptor CD18 on bighorn sheep neutrophils.

  7. Epidemic pasteurellosis in a bighorn sheep population coinciding with the appearance of a domestic sheep.

    Science.gov (United States)

    George, Janet L; Martin, Daniel J; Lukacs, Paul M; Miller, Michael W

    2008-04-01

    A pneumonia epidemic reduced bighorn sheep (Ovis canadensis) survival and recruitment during 1997-2000 in a population comprised of three interconnected wintering herds (Kenosha Mountains, Sugarloaf Mountain, Twin Eagles) that inhabited the Kenosha and Tarryall Mountain ranges in central Colorado, USA. The onset of this epidemic coincided temporally and spatially with the appearance of a single domestic sheep (Ovis aires) on the Sugarloaf Mountain herd's winter range in December 1997. Although only bighorns in the Sugarloaf Mountain herd were affected in 1997-98, cases also occurred during 1998-99 in the other two wintering herds, likely after the epidemic spread via established seasonal movements of male bighorns. In all, we located 86 bighorn carcasses during 1997-2000. Three species of Pasteurella were isolated in various combinations from affected lung tissues from 20 bighorn carcasses where tissues were available and suitable for diagnostic evaluation; with one exception, beta-hemolytic mannheimia (Pasteurella) haemolytica (primarily reported as biogroup 1(G) or 1(alphaG)) was isolated from lung tissues of cases evaluated during winter 1997-98. The epidemic dramatically lowered adult bighorn monthly survival in all three herds; a model that included an acute epidemic effect, differing between sexes and with vaccination status, that diminished linearly over the next 12 mo best represented field data. In addition to the direct mortality associated with epidemics in these three herds, lamb recruitment in years following the pneumonia epidemic also was depressed as compared to years prior to the epidemic. Based on observations presented here, pasteurellosis epidemics in free-ranging bighorn sheep can arise through incursion of domestic sheep onto native ranges, and thus minimizing contact between domestic and bighorn sheep appears to be a logical principle for bighorn sheep conservation.

  8. Immunosuppression in sheep induced by cyclophosphamide, bluetongue virus and their combination: Effect on clinical reaction and viremia.

    Science.gov (United States)

    Chatzinasiou, Evangelia; Chaintoutis, Serafeim C; Dovas, Chrysostomos I; Papanastassopoulou, Maria; Papadopoulos, Orestis

    2017-03-01

    The main purpose of this work was to establish an experimental model for immunosuppression in sheep, and evaluate its possible effects on bluetongue viremia. Animals were allocated in 4 groups: Cy (cyclophosphamide), BT (bluetongue), CyBT (combined Cy and BT) and Co (control), and underwent clinical evaluations, virological testing, peripheral blood immunophenotyping and determination of antiviral humoral immune responses. Intravenous administration of cyclophosphamide (37.5 mg/kg body weight) resulted in immunosuppresion induction, as significant drops were observed in blood leukocytes and lymphocyte subset counts (CD2(+), CD4(+), CD8(+), CD19(+)), lasting 3-10 days after its administration. Reduction in B-cell (CD19(+)) counts was more pronounced than in T-/NK-cell (CD2(+)) counts (92% and 59%, respectively). BTV-9 inoculation resulted in pronounced lymphocytopenia observed from day 1 post-inoculation. Their combined administration resulted in a more intense immunosuppressive effect, as indicated by the greater reduction in lymphocyte, granulocyte, CD4(+) and CD8(+) cell counts. In group CyBT, earlier initiation of fever by one day (day 6 p.i.) compared to group BT (day 7 p.i.), and delay in antibody responses by one day was observed, compared to group BT. Neutralizing antibodies in both groups (BT, CyBT) were detectable from day 10 p.i., but no significant titer differences were observed. Infectious virus titers were detected from day 4 p.i. in group BT and from day 3 in group CyBT. Statistical significances in virus titers were also observed (greatest mean titer difference: 1.4 log10 CEID50/ml RBCs at day 5 p.i., P bluetongue. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Malaysian Twin Registry.

    Science.gov (United States)

    Jahanfar, Shayesteh; Jaffar, Sharifah Halimah

    2013-02-01

    The National Malaysian Twin Registry was established in Royal College of Medicine, Perak, University Kuala Lumpur (UniKL) in June 2008 through a grant provided by UniKL. The general objective is to facilitate scientific research involving participation of twins and their family members in order to answer questions of health and wellbeing relevant to Malaysians. Recruitment is done via mass media, poster, and pamphlets. We now have 266 adult and 204 children twins registered. Several research projects including reproductive health study of twins and the role of co-bedding on growth and development of children are carried out. Registry holds annual activities for twins and seeks to provide health-related information for twins. We seek international collaboration.

  10. Immunohistochemical localization of prostaglandin G/H synthase 1 and 2 in sheep placenta after glucocorticoid-induced and spontaneous labour.

    Science.gov (United States)

    McLaren, W J; Young, I R; Rice, G E

    2000-09-01

    Enhanced prostaglandin production and release by the placenta is an essential element in the normal transition to labour in many animal species. In sheep, expression of prostaglandin G/H synthase (PGHS) is the central enzyme regulating this process. In this study immunohistochemistry was used to examine the distribution of cells expressing PGHS-1 and PGHS-2 in ovine placenta in association with spontaneous parturition (n = 6) and glucocorticoid-induced labour (n = 5). Labour was induced in ewes after the intrafetal injection of betamethasone on day 131 of gestation. Animals administered an intrafetal injection of isotonic saline (n = 5) acted as non-labour controls. In placentomes collected from all groups, immunoreactive PGHS-1 was present in the mononuclear trophoblast cells of the fetal placenta. Cells in the maternal mesenchyme and epithelial syncytium were weakly immunopositive for this enzyme. PGHS-1 immunoreactivity was also demonstrated in the endothelial cells of the chorionic vessels. The PGHS-2 isozyme was localized exclusively to the trophoblast epithelial cells. Immunoreactive PGHS-2 was not detectable in the maternal epithelial syncytium or the stroma of the cotyledons. The binucleate cells of the fetal placenta were consistently immunonegative for both PGHS isozymes. These results indicate that the cellular localization of PGHS-1 and PGHS-2 in ovine placenta does not change during the last 15 days of pregnancy. Co-localization of these isozymes indicates that the source of arachidonic acid and the site of prostanoid formation are the same. Quantitation of the percentage area of positive staining for PGHS-1 and PGHS-2 using image analysis software demonstrated a significant increase in PGHS-2 in the fetal trophoblast after glucocorticoid-induced labour and spontaneous parturition. This finding indicates that increased formation of the PGHS-2 isozyme is responsible for the large increase in prostaglandin production by the ovine placenta at term labour.

  11. Perinatal hepatic infarction in twin-twin transfusion.

    LENUS (Irish Health Repository)

    O'Sullivan, M J

    2012-02-03

    We report a case of a twin pregnancy which was complicated by a twin-twin transfusion in which the recipient twin was noted to have an intra-abdominal echogenic mass. This twin died at two days of age of hepatic infarction. The donor twin was healthy at birth, at thirty weeks\\' gestation, and did not have any subsequent problems. Fetal intra-abdominal echogenicity may be a marker of hepatic infarction.

  12. Twin screw subsurface and surface multiphase pumps

    Energy Technology Data Exchange (ETDEWEB)

    Dass, P. [CAN-K GROUP OF COMPANIES, Edmonton, Alberta (Canada)

    2011-07-01

    A new subsurface twin screw multiphase pump has been developed to replace ESP and other artificial lift technologies. This technology has been under development for a few years, has been field tested and is now going for commercial applications. The subsurface twin screw technology consists of a pair of screws that do not touch and can be run with a top drive or submersible motor; and it carries a lot of benefits. This technology is easy to install and its low slippage makes it highly efficient with heavy oil. In addition twin screw multiphase pumps are capable of handling high viscosity fluids and thus their utilization can save water when used in thermal applications. It also induces savings of chemicals because asphaltenes do not break down easily as well as a reduction in SOR. The subsurface twin screw multiphase pump presented herein is an advanced technology which could be used in thermal applications.

  13. Experimentally Induced Preterm Birth in Sheep Following a Clinical Course of Antenatal Betamethasone: Effects on Growth and Long-Term Survival.

    Science.gov (United States)

    Nguyen, Vivian B; De Matteo, Robert; Harding, Richard; Stefanidis, Aneta; Polglase, Graeme R; Black, M Jane

    2017-08-01

    Preterm births account for approximately 10% of births worldwide, with the majority (∼80%) being moderate preterm. Our aim was to determine the effects of moderate preterm birth on survival and long-term growth of male and female offspring using an ovine model of preterm birth that was preceded by a clinically relevant dose of corticosteroids. Ewes were induced to deliver preterm or at term; those assigned to deliver preterm were administered antenatal betamethasone (11.4 mg, 2 doses, 24 hours apart). The growth (body weight and body dimensions) of offspring was monitored to adulthood (62 weeks) when the animals were humanely killed for organ collection. Survival in the immediate period following preterm birth was high (75% for both sexes). However, there were unexpected deaths between 5 and 12 weeks of age, as a result of vitamin E/selenium deficiency; this only occurred in preterm offspring. From birth until adolescence, preterm lambs were lighter than term lambs (controls). After this time, there was gradual catch-up in body weight in preterm females, whereas in preterm males, body weight remained lower than in controls. Preterm sheep were smaller in stature than controls throughout life. This clinically relevant model of preterm birth leads to equally high survival rates in both sexes and is an excellent animal model in which to examine the effects of moderate preterm birth on growth and development of organ systems into adulthood.

  14. The Brazilian Twin Registry.

    Science.gov (United States)

    Ferreira, Paulo H; Oliveira, Vinicius C; Junqueira, Daniela R; Cisneros, Lígia C; Ferreira, Lucas C; Murphy, Kate; Ordoñana, Juan R; Hopper, John L; Teixeira-Salmela, Luci F

    2016-12-01

    The Brazilian Twin Registry (BTR) was established in 2013 and has impelled twin research in South America. The main aim of the initiative was to create a resource that would be accessible to the Brazilian scientific community as well as international researchers interested in the investigation of the contribution of genetic and environmental factors in the development of common diseases, phenotypes, and human behavior traits. The BTR is a joint effort between academic and governmental institutions from Brazil and Australia. The collaboration includes the Federal University of Minas Gerais (UFMG) in Brazil, the University of Sydney and University of Melbourne in Australia, the Australian Twin Registry, as well as the research foundations CNPq and CAPES in Brazil. The BTR is a member of the International Network of Twin Registries. Recruitment strategies used to register twins have been through participation in a longitudinal study investigating genetic and environmental factors for low back pain occurrence, and from a variety of sources including media campaigns and social networking. Currently, 291 twins are registered in the BTR, with data on demographics, zygosity, anthropometrics, and health history having been collected from 151 twins using a standardized self-reported questionnaire. Future BTR plans include the registration of thousands of Brazilian twins identified from different sources and collaborate nationally and internationally with other research groups interested on twin studies.

  15. Delivery in Twin Gestation

    Directory of Open Access Journals (Sweden)

    Mark T. Peters

    1995-01-01

    Full Text Available Objective: The objective of this study was to determine whether prophylactic treatment with oral broad-spectrum antimicrobial therapy improves pregnancy outcomes in twin gestations.

  16. Suppressed peripheral blood lymphocyte blastogenesis in pre- and postpartal sheep by chronic heat-stress, and suppressive property of heat-stressed sheep serum on lymphocytes.

    Science.gov (United States)

    Niwano, Y; Becker, B A; Mitra, R; Caldwell, C W; Abdalla, E B; Johnson, H D

    1990-01-01

    Phytohemagglutinin (PHA) and concanavalin A (Con A)-induced blastogenesis of peripheral blood lymphocytes was examined in heat-stressed pre- and postpartal sheep. The peak responses of lymphocytes to PHA and Con A in heat-stressed sheep revealed significant reduction before and after parturition compared with those in the corresponding control animals kept under thermoneutral conditions. Furthermore, the effect of serum from control or heat-stressed sheep on PHA-induced lymphocyte blastogenesis was examined. Supplementation of serum from heat-stressed sheep significantly suppressed the blastogenesis of lymphocytes obtained from healthy sheep, bovine, and human donors. Unlike dexamethasone, heat-stressed sheep serum did not inhibit IL-2 production by PHA-stimulated human peripheral blood lymphocytes. These results indicate that the immunosuppression of heat-stressed sheep is in part mediated by serum factor(s) that can modulate T-cell function in a species nonspecific manner.

  17. Perinatal risk factors and neonatal complications in discordant twins admitted to the neonatal intensive care unit

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-rui; LIU Jie; ZENG Chao-mei

    2013-01-01

    Background Many studies have shown a relationship between birth weight discordance and adverse perinatal outcomes.This study aimed to investigate the perinatal risk factors and neonatal complications of discordant twins who are admitted to the neonatal intensive care unit.Methods A total of 87 sets of twins were enrolled in this retrospective study,of which 22 sets were discordant twins and 65 sets were concordant twins.Binary Logistic regression analysis was used to identify the risk factors associated with the occurrence of discordant twins.The common neonatal complications of discordant twins were also investigated.Results Multivariate analysis showed that the use of assisted reproductive techniques,pregnancy-induced hypertension,and unequal placental sharing were risk factors for the occurrence of discordant twins.The incidence of small for gestational age infants and very low birth weight infants of discordant twins was significantly higher,while the birth weight of discordant twins was significantly lower than those of concordant twins.The duration of hospitalization of discordant twins was longer than that of concordant twins.The incidence of several neonatal complications,such as neonatal respiratory distress syndrome and intracranial hemorrhage,was higher in discordant twins than that in concordant twins.The percentage of those requiring pulmonary surfactant and mechanical ventilation was significantly higher in discordant twins than that in concordant twins.Conclusions Use of assisted reproductive techniques,pregnancy-induced hypertension,and unequal placental sharing are perinatal risk factors of discordant twins who are admitted to the neonatal intensive care unit.These infants are also much more likely to suffer from various neonatal complications,especially respiratory and central nervous system diseases.It is important to prevent the occurrence of discordant twins by decreasing these risk factors and timely treatment should be given to discordant

  18. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak Syst

  19. The Danish Twin Registry

    DEFF Research Database (Denmark)

    Skytthe, Axel; Ohm Kyvik, Kirsten; Vilstrup Holm, Niels

    2011-01-01

    Introduction: The Danish Twin Registry is a unique source for studies of genetic, familial and environmental factors on life events, health conditions and diseases. Content: More than 85,000 twin pairs born 1870-2008 in Denmark. Validity and coverage: Four main ascertainment methods have been emp...

  20. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak

  1. Spontaneous Live Twin Tubal Ectopic Pregnancy: A Case Report

    Directory of Open Access Journals (Sweden)

    R Benn

    2016-02-01

    Full Text Available We report the case of a 29-year old G3P1+1 woman with a spontaneously conceived live twin tubal ectopic pregnancy. Her history was significant for infertility for 11 years after an induced abortion. Pelvic ultrasound scan showed live twin ectopic pregnancy and a partial salpingectomy was done.

  2. Deformation twinning and the role of amino acids and magnesium in calcite hardness from molecular simulation.

    Science.gov (United States)

    Côté, A S; Darkins, R; Duffy, D M

    2015-08-21

    We employ classical molecular dynamics to calculate elastic properties and to model the nucleation and propagation of deformation twins in calcite, both as a pure crystal and with magnesium and aspartate inclusions. The twinning is induced by applying uniaxial strain to the crystal and relaxing all stress components except the uniaxial component. A detailed analysis of the atomistic processes reveal that the twinning mechanism involves small displacements of the Ca ions and cooperative rotations of the CO3 ions. The volume of the twinned region expands under increased uniaxial strain via the propagation of steps along the twin boundaries. The energy cost of the twin boundaries is compensated by the reduced hydrostatic stress and strain energy. The presence of biogenic impurities is shown to decrease the strain required to induce twin formation in calcite and, thus, the yield stress. This increased propensity for twinning provides a possible explanation for the increased hardness and penetration resistance observed experimentally in biominerals.

  3. Infestation and pathological lesions of some lymph nodes induced by Linguatula serrata nymphs in sheep slaughtered in Shahrekord Area(Southwest Iran)

    Institute of Scientific and Technical Information of China (English)

    Hamidreza; Azizi; Hossein; Nourani; Abdollah; Moradi

    2015-01-01

    Objective: To determine the infection rates of mesenteric and mediastinal lymph nodes in relation to Linguatula serrata(L. serrata) nymphs. Methods: In the present study, mesenteric and mediastinal lymph nodes of 200 sheep with different sex and age that were slaughtered in a Shahrekord slaughterhouse were collected. The lymph nodes were examined macroscopically and for histopathological examination, tissue samples were taken from the gross lesions processed routinely by paraffin method and stained with hematoxylin and eosin. Results: Out of 200 examined sheep, the mesenteric lymph nodes in 18 sheep(9%) and the mediastinal lymph nodes of 9 sheep(4.5%) were infected by L. serrata nymphs. The infection rate increased with age, but no significant difference was observed between males and females or the two types of lymph nodes(P > 0.01). Different nonspecific gross and macroscopic lesions were seen in infected lymph nodes. L. serrata nymph sections were observed in some histopathological slides. Conclusions: It is concluded that the sheep may play an important role in linguatulosis of final hosts and human beings in this region.

  4. Susceptibility of Dall sheep (Ovis dalli dalli) to pneumonia caused by Pasteurella haemolytica.

    Science.gov (United States)

    Foreyt, W J; Silflow, R M; Lagerquist, J E

    1996-10-01

    We evaluated susceptibility of Dall sheep (Ovis dalli dalli) to bacterial pneumonia induced by two strains of Pasteurella haemolytica of domestic sheep origin by evaluating the sensitivity of blood neutrophils of eight Dall sheep to lysis by cytotoxins of P. haemolytica, and by intratracheal inoculation of three Dall sheep, two bighorn sheep (Ovis canadensis), and two domestic sheep with 3.7 x 10(6) or 2.5 x 10(7) colony forming units of P. haemolytica. Neutrophils from the Dall sheep were more sensitive to lysis by cytotoxins from supernatants of a P. haemolytica, biotype A, serotype 2 (A2), of domestic sheep origin, than were neutrophils from six bighorn sheep. This cytotoxic bacterium was the same isolate that was used for intratracheal inoculation of two Dall sheep and two domestic sheep. Inoculation of this cytotoxic P. haemolytica A2 resulted in fatal fibrinopurulent pleuropneumonia in the first Dall sheep within 24 hr of inoculation, and pneumonic lesions in the second Dall sheep before it was euthanized 52 hr after inoculation. This strain of P. haemolytica A2 did not cause respiratory disease when inoculated into two domestic sheep. A noncytotoxic strain of P. haemolytica; biotype T, serotype 3,4,10 of domestic sheep origin did not result in pneumonia in the third Dall sheep or two bighorn sheep. Prior to inoculation, P. haemolytica, biotype T isolates were obtained from all three Dall sheep, but none of these isolates was cytotoxic. At necropsy, cytotoxic P. haemolytica A2 was isolated from lungs and other tissues of the two pneumonic Dall sheep. Based on these results, we conclude that Dall sheep appear to be at least as sensitive as bighorn sheep to pneumonia caused by P. haemolytica A2 of domestic sheep origin. Because in vitro and in vivo results appear closely correlated in this and other studies, we believe with additional evaluation and standardization, neutrophil cytotoxicity tests may serve as a substitute for live animal challenges in future

  5. Expression of VP7, a Bluetongue virus group specific antigen by viral vectors: analysis of the induced immune responses and evaluation of protective potential in sheep.

    Directory of Open Access Journals (Sweden)

    Coraline Bouet-Cararo

    Full Text Available Bluetongue virus (BTV is an economically important Orbivirus transmitted by biting midges to domestic and wild ruminants. The need for new vaccines has been highlighted by the occurrence of repeated outbreaks caused by different BTV serotypes since 1998. The major group-reactive antigen of BTV, VP7, is conserved in the 26 serotypes described so far, and its role in the induction of protective immunity has been proposed. Viral-based vectors as antigen delivery systems display considerable promise as veterinary vaccine candidates. In this paper we have evaluated the capacity of the BTV-2 serotype VP7 core protein expressed by either a non-replicative canine adenovirus type 2 (Cav-VP7 R0 or a leporipoxvirus (SG33-VP7, to induce immune responses in sheep. Humoral responses were elicited against VP7 in almost all animals that received the recombinant vectors. Both Cav-VP7 R0 and SG33-VP7 stimulated an antigen-specific CD4+ response and Cav-VP7 R0 stimulated substantial proliferation of antigen-specific CD8+ lymphocytes. Encouraged by the results obtained with the Cav-VP7 R0 vaccine vector, immunized animals were challenged with either the homologous BTV-2 or the heterologous BTV-8 serotype and viral burden in plasma was followed by real-time RT-PCR. The immune responses triggered by Cav-VP7 R0 were insufficient to afford protective immunity against BTV infection, despite partial protection obtained against homologous challenge. This work underscores the need to further characterize the role of BTV proteins in cross-protective immunity.

  6. Expression of VP7, a Bluetongue Virus Group Specific Antigen by Viral Vectors: Analysis of the Induced Immune Responses and Evaluation of Protective Potential in Sheep

    Science.gov (United States)

    Bouet-Cararo, Coraline; Contreras, Vanessa; Caruso, Agathe; Top, Sokunthea; Szelechowski, Marion; Bergeron, Corinne; Viarouge, Cyril; Desprat, Alexandra; Relmy, Anthony; Guibert, Jean-Michel; Dubois, Eric; Thiery, Richard; Bréard, Emmanuel; Bertagnoli, Stephane; Richardson, Jennifer; Foucras, Gilles; Meyer, Gilles; Schwartz-Cornil, Isabelle; Zientara, Stephan; Klonjkowski, Bernard

    2014-01-01

    Bluetongue virus (BTV) is an economically important Orbivirus transmitted by biting midges to domestic and wild ruminants. The need for new vaccines has been highlighted by the occurrence of repeated outbreaks caused by different BTV serotypes since 1998. The major group-reactive antigen of BTV, VP7, is conserved in the 26 serotypes described so far, and its role in the induction of protective immunity has been proposed. Viral-based vectors as antigen delivery systems display considerable promise as veterinary vaccine candidates. In this paper we have evaluated the capacity of the BTV-2 serotype VP7 core protein expressed by either a non-replicative canine adenovirus type 2 (Cav-VP7 R0) or a leporipoxvirus (SG33-VP7), to induce immune responses in sheep. Humoral responses were elicited against VP7 in almost all animals that received the recombinant vectors. Both Cav-VP7 R0 and SG33-VP7 stimulated an antigen-specific CD4+ response and Cav-VP7 R0 stimulated substantial proliferation of antigen-specific CD8+ lymphocytes. Encouraged by the results obtained with the Cav-VP7 R0 vaccine vector, immunized animals were challenged with either the homologous BTV-2 or the heterologous BTV-8 serotype and viral burden in plasma was followed by real-time RT-PCR. The immune responses triggered by Cav-VP7 R0 were insufficient to afford protective immunity against BTV infection, despite partial protection obtained against homologous challenge. This work underscores the need to further characterize the role of BTV proteins in cross-protective immunity. PMID:25364822

  7. Experimental evidence of twin fast metastable H(2S) atoms from dissociation of cold H_2 induced by electrons

    CERN Document Server

    Robert, J; Carvalho, C R; Jalbert, Ginette; Nascimento, R F; Trimeche, A; Dulieu, O; Medina, Aline; Carvalho, Carla; Faria, N V de Castro

    2013-01-01

    We report the direct detection of two metastable H(2S) atoms coming from the dissociation of a single cold H_2 molecule, in coincidence measurements. The molecular dissociation was induced by electron impact in order to avoid limitations by the selection rules governing radiative transitions. Two detectors, placed close from the collision center, measure the neutral metastable H(2S) through a localized quenching process, which mixes the H(2S) state with the H(2P), leading to a Lyman-\\alpha detection. Our data show the accomplishment of a coincidence measurement which proves for the first time the existence of the H(2S)-H(2S) dissociation channel.

  8. Data in brief: Transcriptome analysis of induced pluripotent stem cells from monozygotic twins discordant for trisomy 21

    Directory of Open Access Journals (Sweden)

    Youssef Hibaoui

    2014-12-01

    Full Text Available Down syndrome (DS, trisomy 21, is the most common viable chromosomal disorder, with an incidence of 1 in 800 live births. Its phenotypic characteristics include intellectual impairment and several other developmental abnormalities, for the majority of which the pathogenetic mechanisms remain unknown. In this “Data in Brief” paper, we sum up the whole genome analysis by mRNA sequencing of normal and DS induced pluripotent stem cells that was recently published by Hibaoui et al. in EMBO molecular medicine.

  9. Neonatal status of twins

    Directory of Open Access Journals (Sweden)

    Božinović Dragica

    2012-01-01

    Full Text Available Multiple pregnancy is a pregnancy where more than one fetus develops simultaneously in the womb, as a result of the ovulation and fertilization of more than one egg. It is relatively rare in humans and represents the rest of the phylogenetic stages. The most common are twins and they indicate the development of two fetuses in the womb. The frequency of twin pregnancies is about 1%. Multiple pregnancies belong to a group of high-risk pregnancies because of the many complications that occur during the pregnancy: higher number of premature deliveries, bleeding, early neonatal complications and higher perinatal morbidity and mortality. Such pregnancies and infants require greater supervision and monitoring. The aim of this study was to determine the percentage of baby twins born at the maternity ward of the General Hospital in Prokuplje and their morbidity and mortality. Data on the total number of deliveries, number of twins, parity and maternal age, gestational age, body weight of twins, method of delivery, Apgar score and perinatal mortality were collected and statistically analyzed by means of retrospective analysis of operative birth and neonatal protocol for 6 years (2005 of 2010. Out of 4527 mothers who gave birth 43 were pairs of twins, or 0.95% of women gave birth to twins. These babies are more likely born by Caesarean section, but delivered with slightly lower birth weight.

  10. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2016-01-01

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  11. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2017-01-01

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  12. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2017-01-31

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  13. Cloning and functional analysis of sheep U6 promoters.

    Science.gov (United States)

    Hu, Shengwei; Ni, Wei; Hazi, Wureli; Zhang, Hui; Zhang, Na; Meng, Ren; Chen, Chuangfu

    2011-01-01

    Gene silencing mediated by small interfering RNA has become a powerful biological tool for the regulation of gene expression. In order to develop an effective short hairpin RNA (shRNA) expression vector, specifically for use in sheep species, we have identified two sheep U6 promoters based on the highly conserved polymerase III promoter elements. Promoter activity was measured by U6 promoter-driven shRNA to suppress enhanced green fluorescent protein (EGFP) expression. The knock down assay demonstrated that the two sheep U6 promoters and mouse U6 promoter induced a similar level of EGFP knockdown. These results suggest that the two sheep U6 promoters could efficiently drive shRNA expression for gene silencing and may have applications in RNAi-based sheep research.

  14. Medetomidine-midazolam sedation in sheep.

    Science.gov (United States)

    Raekallio, M; Tulamo, R M; Valtamo, T

    1998-01-01

    Seven sheep were sedated 3 times: with medetomidine (15 micrograms kg-1), with midazolam (0.1 mg kg-1) and with a combination of the drugs. All drugs were administered intravenously. Heart and respiratory rates were measured. Arterial blood samples were collected, and PaO2, PaCO2, pH, haemoglobin concentration and saturation, and base excess were determined. Systolic and mean arterial pressures were recorded before and after the treatment with medetomidine-midazolam. Midazolam increased the time of recumbency induced by medetomidine. After administration of midazolam alone, 4 of the 7 sheep were sedated and the other 3 were excited. Heart rate decreased after both medetomidine and medetomidine-midazolam. One sheep suffered a cardiac arrest after medetomidine-midazolam injection, and it required resuscitation. PaO2 and haemoglobin oxygen saturation decreased after medetomidine, and medetomidine-midazolam caused a marked hypoxaemia. PaCO2 increased after medetomidine, both alone and combined with midazolam, but arterial pH was within the reference values after all drug administrations. Systolic and mean arterial pressures decreased after medetomidine-midazolam. This study indicates that though in sheep midazolam potentiates the sedative effect of medetomidine, the combination of medetomidine and midazolam also reduces the in PaO2 and haemoglobin oxygen saturation more than medetomidine alone. The results indicate that a medetomidine-midazolam combination is unsafe for sheep at the doses studied.

  15. Dairy Sheep Nutrition

    OpenAIRE

    Rosanna Scipioni

    2010-01-01

    This book, edited by the colleague Giuseppe Pulina, is the result of the project "Further development of a diet formulation model for sheep and goat", supported by the Ministry of Agricultural and Forestry Policies, in Italy.

  16. Physiological and behavioral responses of sheep to gaseous ammonia.

    Science.gov (United States)

    Phillips, C J C; Pines, M K; Latter, M; Muller, T; Petherick, J C; Norman, S T; Gaughan, J B

    2012-05-01

    Ammonia can accumulate in highly stocked sheep accommodation, for example during live export shipments, and could affect sheep health and welfare. Thus, the objective of this experiment was to test the effects of 4 NH(3) concentrations, 4 (control), 12, 21, and 34 mg/m(3), on the physiology and behavior of wether sheep. Sheep were held for 12 d under a micro-climate and stocking density similar to shipboard conditions recorded on voyages from Australia to the Middle East during the northern hemispheric summer. Ammonia increased macrophage activity in transtracheal aspirations, indicating active pulmonary inflammation; however, it had no effect (P > 0.05) on hematological variables. Feed intake decreased (P = 0.002) in proportion to ammonia concentration, and BW gain decreased (P sheep were less active, with less locomotion, pawing, and panting. Twenty-eight days after exposure to NH(3), the pulmonary macrophage activity and BW of the sheep returned to that of sheep exposed to only 4 mg/m(3). It was concluded that NH(3) induced a temporary inflammatory response of the respiratory system and reduced BW gain, which together indicated a transitory adverse effect on the welfare of sheep.

  17. Reductions of plant cover induced by sheep grazing change the above-belowground partition and chemistry of organic C stocks in arid rangelands of Patagonian Monte, Argentina.

    Science.gov (United States)

    Larreguy, C; Carrera, A L; Bertiller, M B

    2017-09-01

    The objective of this study was to estimate the size and chemical quality of the total organic C stock and its partition between above-belowground plant parts and soil at sites with different plant cover induced by sheep grazing in the arid Patagonian Monte. This study was conducted at six representative sites with increasing signs of canopy disturbance attributed to grazing pressure. We used faeces density as a proxy of grazing pressure at each site. We assessed the total plant cover, shrub and perennial grass cover, total standing aboveground biomass (AGB), litter mass and belowground biomass (BGB) at each site. We further estimated the content of organic C, lignin and soluble phenols in plant compartments and the content of organic C, organic C in humic substances (recalcitrant C) and water soluble C (labile C) in soil at each site. Total plant cover was significantly related to grazing pressure. Standing AGB and litter mass decreased with increasing canopy disturbance while BGB did not vary across sites. Total organic C stock and the organic C stock in standing AGB increased with increasing total plant, shrub, and perennial grass cover. The organic C stock in litter mass increased with increasing total plant and shrub cover, while the organic C stock in BGB did not vary across sites. Lignin content in plant compartments increased with increasing total and shrub cover, while soluble phenols content did not change across sites. The organic C stock and the water soluble C content in soil were positively associated with perennial grass cover. Changes in total plant cover induced by grazing pressure negatively affected the size of the total organic C stock, having minor impact on the size of belowground than aboveground components. The reduction of perennial grass cover was reflected in decreasing chemical quality of the organic C stock in soil. Accordingly, plant managerial strategies should not only be focused on the amount of organic C sequestered but also on the

  18. Twin-twin Transfusion Syndrome with a Single Ectopic Kidney in a Twin Donor. Case Presentation

    Directory of Open Access Journals (Sweden)

    Gerardo Rogelio Robaina Castellanos

    2016-10-01

    Full Text Available Twin-twin Transfusion Syndrome presents more frequently in diamniotic monochromic twins. In advanced stages and without prenatal intervention, is associated to high rates of peri natal mortality and neurological sequel in the survivors. It is presented a case of a pair of twins with severe depression at birth in which it was diagnosed a Twin-twin Transfusion Syndrome, later confirmed with the presence of anemia in the donor twin and polycythemia in the receptor twin. Both twins had an unfavourable evolution with an early neonatal death. Necropsy findings were comparable with secondary damage to the syndrome, with the particularity that both had evidences of pulmonary infection and a renal malformation in the donor twin which is not included in the proper malformations of this syndrome. The objective of this work is to point out the essential elements for the diagnosis and antenatal treatment for this disease through the peculiarities of the presented case.

  19. Fullerton Virtual Twin Study.

    Science.gov (United States)

    Segal, Nancy L

    2006-12-01

    Virtual twins (VTs; same-age unrelated siblings reared together from early infancy) have been studied at California State University (CSU), Fullerton since 1991. The current sample includes over 130 pairs. Past and current research have research have focused on siblings' similarities and differences in general intelligence and body size. Future research in these areas will continue as new pairs continue to be identified. These studies will be supplemented by analyses of personality, social relations and adjustment using monozygotic (MZ) twins, dizygotic (DZ) twins, full siblings and friends, as well as new VTs, who have participated in Twins, Adoptees, Peers and Siblings (TAPS), a collaborative project conducted between CSU Fullerton and the University of San Francisco, from 2002 to 2006.

  20. Induction of photosensitivity in sheep with Erodium moschatum (L. L'Hérit

    Directory of Open Access Journals (Sweden)

    J.C. Stroebel

    2002-07-01

    Full Text Available Erodium moschatum is an exotic weed in the southern and southwestern coastal areas of the Western Cape Province (WCP, South Africa. It has been suspected as the cause of photosensitivity in sheep. However, attempts to induce photosensitivity by dosing it to sheep have thus far been unsuccessful. During August 1999, 2 sheep suffering from severe photosensitivity were presented for clinical examination to the Western Cape Provincial Veterinary Laboratory (WCPVL. One sheep was sacrificed for autopsy. Except for skin lesions associated with photosensitivity, no icterus or other lesions were present. Histopathological examination of affected skin revealed epidermal necrosis while the liver had no microscopic lesions. It was therefore concluded that the sheep might have been suffering from primary photosensitivity. The farmfrom which the sheep came, situated in the Malmesbury district, WCP, was visited to determine the source of the photodynamic agent. The flock from which the sheep originated had been grazing in a camp where E. moschatum was growing abundantly and had been heavily grazed. Some remaining Erodium in the camp was collected, pulped and dosed over a period of 7 days to an adult sheep. Another sheep was dosed simultaneously with Erodium growing on the premises of the WCPVL. Both sheep developed mild photosensitivity, which was confirmed by histopathological examination of skin biopsies. It was concluded that E. moschatum can induce photosensitivity (probably the primary type in sheep if ingested in large quantities.

  1. Craniofacial anomalies in twins.

    Science.gov (United States)

    Keusch, C F; Mulliken, J B; Kaplan, L C

    1991-01-01

    Studies of twins provide insight into the relative contribution of genetic and environmental factors in the causality of structural anomalies. Thirty-five affected twin pairs were identified from a group of 1114 patients with congenital craniofacial deformities evaluated from 1972 to 1989. Forty-three of these 70 twins exhibited one or more craniofacial anomalies; these were analyzed for dysmorphic characteristics, zygosity, concordance, and family history. The anomalies were categorized into two groups: malformations and deformations. The malformations (n = 36) included hemifacial microsomia (n = 10), cleft lip and palate (n = 8), cleft palate (n = 4), rare facial cleft (n = 2), craniosynostosis (n = 2), Binder syndrome (n = 2), Treacher Collins syndrome (n = 2), craniopagus (n = 2), CHARGE association (n = 1), frontonasal dysplasia (n = 2), and constricted ears (n = 1). The deformations (n = 7) included plagiocephaly (n = 5), hemifacial hypoplasia (n = 1), and micrognathia (n = 1). Twenty-one monozygotic and 14 dizygotic twin pairs were identified. The concordance rate was 33 percent for monozygotic twins and 7 percent for dizygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Twin delivery: how should the second twin be delivered?

    Science.gov (United States)

    Olofsson, P; Rydhström, H

    1985-11-01

    In a series of 803 pairs of twins born between 1973 and 1982, 0.33% of second twins were delivered by cesarean section after vaginal delivery of the first twin. During the last year the frequency has increased to 7%, calling attention to the problem of declining obstetric skills and experience. This has caused us to update the routines of intrapartum management of twin gestations. In the present program only commonly available obstetric techniques are used. The potentially hazardous twin delivery is excluded from a trial of vaginal delivery. Hopefully, the program will help other obstetricians to decide in favor of vaginal delivery in selected twin gestations.

  3. Dependency of deformation twinning on grain orientation in an FCC and a HCP metal

    Institute of Scientific and Technical Information of China (English)

    YANG Ping

    2007-01-01

    Twinning plays important roles in HCP metals and those FCC metals with low stacking fault energy.The structural difierence of two types of metals makes quite different contributions of twinning to plasticity The variety of grain orientation in polycrystalline metals causes the inhomogeneous occurrence of twinning and further distinct transformation kinetics of twinning as strain increases and texture develops.This changes finally the work hardening behavior and mechanical properties.This Paper reveals the dependency of twinning on grain orientation in an FCC TWIP(twinning induced plasticity)steel with high Mn content and in a magnesium alloy using electron-backscatter-difiraction(EBSD) technique,and analyzes the characteristies of twinning in the two types of metals by Schmid factor calculation.In addition,the relation of twinning and shear banding, as well as their influence on properties are discussed.

  4. Controlled peroxide-induced degradation of polypropylene in a twin-screw extruder: change of molecular weight distribution under conditions controlled by micromixing

    NARCIS (Netherlands)

    Iedema, P.D.; Remerie, K.; van der Ham, M.; Biemond, E.; Tacx, J.

    2011-01-01

    Controlled degradation of polypropylene (PP) by peroxide was carried out in a laboratory twin-screw extruder ZSK 18 and the change in Molecular Weight Distribution (MWD) was measured using Size Exclusion Chromatography-Differential Viscosimetry (SEC-DV). The MWD results were compared to MWD predicti

  5. An unanticipated cardiac arrest and unusual post-resuscitation psycho-behavioural phenomena/near death experience in a patient with pregnancy induced hypertension and twin pregnancy undergoing elective lower segment caesarean section

    Directory of Open Access Journals (Sweden)

    Mridul M Panditrao

    2010-01-01

    Full Text Available A case report of a primigravida, who was admitted with severe pregnancy induced hypertension (BP 160/122 mmHg and twin pregnancy, is presented here. Antihypertensive therapy was initiated. Elective LSCS under general anaesthesia was planned. After the birth of both the babies, intramyometrial injections of Carboprost and Pitocin were administered. Immediately, she suffered cardiac arrest. Cardio pulmonary resucitation (CPR was started and within 3 minutes, she was successfully resuscitated. The patient initially showed peculiar psychological changes and with passage of time, certain psycho-behavioural patterns emerged which could be attributed to near death experiences, as described in this case report.

  6. An unanticipated cardiac arrest and unusual post-resuscitation psycho-behavioural phenomena/near death experience in a patient with pregnancy induced hypertension and twin pregnancy undergoing elective lower segment caesarean section.

    Science.gov (United States)

    Panditrao, Mridul M; Singh, Chanchal; Panditrao, Minnu M

    2010-09-01

    A case report of a primigravida, who was admitted with severe pregnancy induced hypertension (BP 160/122 mmHg) and twin pregnancy, is presented here. Antihypertensive therapy was initiated. Elective LSCS under general anaesthesia was planned. After the birth of both the babies, intramyometrial injections of Carboprost and Pitocin were administered. Immediately, she suffered cardiac arrest. Cardio pulmonary resucitation (CPR) was started and within 3 minutes, she was successfully resuscitated. The patient initially showed peculiar psychological changes and with passage of time, certain psycho-behavioural patterns emerged which could be attributed to near death experiences, as described in this case report.

  7. Sheep fertility during induction and estrus synchronisation in the anoestrus season depending of the body weight of tested eves

    Directory of Open Access Journals (Sweden)

    Mekić Civijan

    2014-01-01

    Full Text Available The aim of this research was to determine if there are differences in sexual reaction of the grown sheep II de frans breed depending on the body weight of treated eves during induction and synchronization of estrus with fluorogestonacetate (FGA + PMSG in anoestrus season. Total number of 262 eves was treated and they were divided in to three groups. The first group consisted of the sheep whose body weight was from 40 to 50kg, the second group of the sheep whose weight was from 50-60kg and the third group of the sheep whose weight was above 60kg. Each group received sponges of FGA. After removal of the sponges all sheep received intramuscular injection of 500 i.u of PMSG. The "Sugonal" prepared by Veterinary institute Subotica was used. After two days the insemination was conducted. The results show that from first group 43.78% sheep lambed, from second group 46.66% and from third group 59.32%. Average sheep fertility after treatments was for the first group 113.28%, 118.37% for the second group and 137.14% for the third group. The ratio of singles, twins and triplets was for the first group 72:28:0 %, for the second group 70.69:24.14:5.17%, and for the third group 47.92:45.83:6.25%. Determined differences between number of lambed sheep and treated sheep, fertility and number of twins, as well as between investigated groups were statistically significant (P<0,05. Conclusion is that sheep of body weight above 60kg have had significantly better reaction to the treatment.

  8. Bovine spongiform encephalopathy in sheep?

    NARCIS (Netherlands)

    Schreuder, B.E.C.; Somerville, R.A.

    2003-01-01

    Bovine spongiform encephalopathy (BSE) in sheep has not been identified under natural conditions at the time of writing and remains a hypothetical issue. However, rumours about the possible finding of a BSE-like isolate in sheep have led to great unrest within the sheep industry, among the general p

  9. The Texas Twin Project.

    Science.gov (United States)

    Harden, K Paige; Tucker-Drob, Elliot M; Tackett, Jennifer L

    2013-02-01

    Socioeconomic position, racial/ethnic minority status, and other characteristics of the macro-environment may be important moderators of genetic influence on a wide array of psychosocial outcomes. Designed to maximize representation of low socioeconomic status families and racial/ethnic minorities, the Texas Twin Project is an ongoing study of school-age twins (preschool through 12th grade) enrolled in public schools in the Austin, Texas and Houston, Texas metropolitan areas. School rosters are used to identify twin families from a target population with sizable populations of African American (18%), Hispanic/Latino (48%), and non-Hispanic White (27%) children and adolescents, over half of whom meet US guidelines for classification as economically disadvantaged. Initial efforts have focused on a large-scale, family-based survey study involving both parent and child reports of personality, psychopathology, physical health, academic interests, parent-child relationships, and aspects of the home environment. In addition, the Texas Twin Project is the basis for an in-laboratory study of adolescent decision-making, delinquency, and substance use. Future directions include geographic expansion of the sample to the entire state of Texas (with a population of over 25 million) and genotyping of participating twins.

  10. [Sheep wool granuloma].

    Science.gov (United States)

    Lambert, D; Terrussot, M C; Dalac, S; Boulitrop-Morvan, C

    1995-01-01

    We report the unusual case of cutaneous foreign body granulomas provoked by sheep wool. A 45-years old woman presented within one year two episodes of a papular eruption on her neck and limbs. She was working as a farmer's wife and each episode occurred after preparing the ewes for coupling. She had to keep a tight hold on the ewes while the farmer introduced warm and moist compresses in the genitals of the animals. Each diseased skin area was closely related to the tight contact with the sheep's wool and on histological slides each granuloma was centered by a tiny ply of wool. This foreign body reaction may be compared to the trichogranulomas of hairdressers. In sheep breeders this occupational practice is very usual and one may wonder why this type of reaction seems so rare.

  11. Hypoalbuminemia in Donors with Twin-Twin Transfusion Syndrome

    NARCIS (Netherlands)

    Verbeek, L.; Middeldorp, J. M.; Hulzebos, C. V.; Oepkes, D.; Walther, F. J.; Lopriore, E.

    2013-01-01

    Objective: To estimate the differences in albumin levels between donors and recipients with twin-twin transfusion syndrome (TTTS). Methods: We performed a matched case-control study including twin pairs with TTTS treated conservatively (conservative group) or with fetoscopic laser surgery (laser gro

  12. Placental development in the sheep and its relation to fetal development. A qualitative and quantitative anatomic and histologic study

    NARCIS (Netherlands)

    Stegeman, Jenny H.J.

    1974-01-01

    A quantitative macroscopic and microscopic investigation was performed upon the placenta of the sheep. Macroscopic data were obtained from 235 cases of single pregnancy, 285 cases of twin pregnancy, 45 cases of triplet pregnancy, and from one case of quadrulet pregnancy. Macroscopic data obtained in

  13. Dialysis for twins

    DEFF Research Database (Denmark)

    Gramkow, Ann-Maria; Aarup, Michael; Andersen, L. L. T.

    2014-01-01

    A 32-year-old woman with known stage-4 chronic kidney disease due to lupus nephritis presented with twin pregnancy after in vitro fertilization at a gestational age of 24 weeks + 3 days because of imminent preterm labour. Repeated ultrasound evaluations confirmed intrauterine growth restriction...... in both twins and polyhydramnios as the cause of imminent preterm labour. After initiation of haemodialysis treatment, ultrasound evaluation showed a significant decrease in amniotic fluids, and also reduction in blood urea nitrogen and in clinical complaints could be observed. At a gestational age of 28...... weeks + 4 days, delivery was performed by Caesarean section. This case study shows that effective treatment of elevated uraemic toxins significantly reduced the morbidity risks of the twins....

  14. The Danish Twin Registry

    DEFF Research Database (Denmark)

    Skytthe, Axel; Christiansen, Lene; Kyvik, Kirsten Ohm;

    2013-01-01

    decade of combining questionnaire and survey data with national demographic, social, and health registers in Statistics Denmark. Second, we describe our most recent data collection effort, which was conducted during the period 2008-2011 and included both in-person assessments of 14,000+ twins born 1931......Over the last 60 years, the resources and the research in the Danish Twin Registry (DTR) have periodically been summarized. Here, we give a short overview of the DTR and a more comprehensive description of new developments in the twenty-first century. First, we outline our experience over the last......-1969 and sampling of biological material, hereby expanding and consolidating the DTR biobank. Third, two examples of intensively studied twin cohorts are given. The new developments in the DTR in the last decade have facilitated the ongoing research and laid the groundwork for new research directions....

  15. Maternal nutrition in twin pregnancy.

    Science.gov (United States)

    Campbell, D M; MacGillivray, I; Tuttle, S

    1982-01-01

    Energy and protein intake as measured by 24-hour urinary nitrogen values are similar in twin and singleton pregnancies. The relationship between urinary nitrogen and nitrogen intake is equally significant in twin and singleton pregnancies. Dietary zinc, copper, and iron are not different in women with twins, nor are the levels of these elements in plasma. These observations are surprising in view of the extra fetal demands on the mother and the different adaptation of twin pregnancies.

  16. Relativistic twins or sextuplets?

    CERN Document Server

    Sheldon, E S

    2003-01-01

    A recent study of the relativistic twin 'paradox' by Soni in this journal affirmed that 'A simple solution of the twin paradox also shows anomalous behaviour of rigidly connected distant clocks' but entailed a pedagogic hurdle which the present treatment aims to surmount. Two scenarios are presented: the first 'flight-plan' is akin to that depicted by Soni, with constant-velocity segments, while the second portrays an alternative mission undertaken with sustained acceleration and deceleration, illustrated quantitatively for a two-way spacecraft flight from Earth to Polaris (465.9 light years distant) and back.

  17. Imaging of conjoined twins

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, Kieran [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Kiely, Edward M.; Spitz, Lewis [Great Ormond Street Hospital for Children, Department of Surgery, London (United Kingdom)

    2006-09-15

    The incidence of conjoined twins is estimated to be around 1 in 250,000 live births. There is a distinct female predominance. In this paper the imaging of conjoined twins both antenatally and postnatally is reviewed, in particular taking into consideration recent advances with multidetector CT. Accurate counselling of parents regarding the likely outcome of the pregnancy and the likelihood of successful separation is dependent on good prenatal imaging with ultrasound and MRI. Planning of postnatal surgical separation is aided by accurate preoperative imaging which, depending on the conjoined area, will encompass many imaging modalities, but often relies heavily on CT scanning. (orig.)

  18. The Twin Interdisciplinary Neuroticism Study

    NARCIS (Netherlands)

    Riese, Harriette; Rijsdijk, Fruehling V.; Snieder, Harold; Ormel, Johan

    The Twin Interdisciplinary Neuroticism Study (TWINS) is a three-wave study including >800 twin pairs from the northern part of the Netherlands. The aim of the study is to unravel why neuroticism reflects vulnerability to mental disorders. In this study, we focus on possible mechanisms underlying

  19. Prenatal undernutrition and postnatal overnutrition alter thyroid hormone axis function in sheep

    DEFF Research Database (Denmark)

    Johnsen, Lærke; Kongsted, Anna Hauntoft; Nielsen, Mette Olaf

    2013-01-01

    -bearing sheep were fed one of two diets during late gestation: NORM (fulfilling energy and protein requirements) or LOW (50% of NORM). From day-3 to 6-months after birth (around puberty) the twin lambs were assigned to each their diet: conventional (CONV) or high-carbohydrate-high-fat (HCHF), where after half......Mounting evidence led us to hypothesize that: 1) function of the thyroid hormone (TH) axis can be programmed by late-gestation undernutrition (LG-UN), and 2) early-postnatal-life overnutrition (EL-ON) exacerbates the fetal impacts on TH-axis function. In a 2×2 factorial experiment, 21 twin...

  20. Identical Twins Raised Apart

    Science.gov (United States)

    Farnsworth, David L.

    2015-01-01

    This article describes a bivariate data set that is interesting to students. Indeed, this particular data set, which involves twins and IQ, has sparked more student interest than any other set that I have presented. Specific uses of the data set are presented.

  1. Sleep Terrors in Twins

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2008-12-01

    Full Text Available In an attempt to clarify the genetic and environmental causes of sleep terrors in childhood, reasearchers in Canada followed 390 pairs of monozygotic and dizygotic twins by assessing the frequency of sleep terrors at 18 and 30 months of age using a questionnaire administered to the biological mothers.

  2. Twin Hub Network (poster)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.

    2014-01-01

    Twin hub network, a European Interreg IVB project, aims at making intermodal rail transport within, to and from North West Europe more competitive, in particular between seaports and inland terminals. Improving rail competitiveness enables to shift freight flows from road to rail, providing a more s

  3. Amelia in Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Davari Tanha Fatemeh

    2009-04-01

    Full Text Available Limb bud first appears during the third week of gestation with the upper limb buds appearing a few days before the lower limb buds. Complete absence of one or more limbs, called Amelia, occurs prior to the eighth week of gestation. We report a case of Amelia in a twin gestation.

  4. TWIN BLOCK (Studi Pustaka

    Directory of Open Access Journals (Sweden)

    Evie Lamtiur

    2015-08-01

    Full Text Available Young patients with class II skeletal malocclusion are often found. To avoid further discrepancy of this case, myofunctional therapy is one of the options. Functional appliance often used for such treatment. Functional appliance has been modified since activator was introduced by Andresen. With its bulky shape, activator makes difficulty for patient to speak and eat. Patient unable to wear it full time due to uncomfortness and negative facial appearance. In 1977, Clark developed twin block to overcome the weakness of previous appliances. A more simple design allows patient to be more comfortable and willing to wear it longer. Twin block is myofunctional appliance to reposition the mandible forward for skeletal class II correction with retruded mandible. This paper describes the design, clinical management effects of twin block treatment and brief case presentation using twin block appliance. Similar to the study reports found, this case revealed improvement of facial appearance, decrease overjet and overbite, improvement of molar relationship and good compliance of patient.

  5. Twin-twin transfusion syndrome - diagnosis and prognosis

    Directory of Open Access Journals (Sweden)

    Hajrić-Egić Amira

    2003-01-01

    Full Text Available Twin-twin transfusion syndrome is a serious complication of monozygotic, monochorionic, diamniotic twins resulting from transplacental vascular communications. In this syndrome blood is thought to be shunted from one twin - donor,who develops anaemia,growth retardation and oligoamnios, to the other twin - recipient,who becomes plethoric,macrosomic and develops polyhydroamnios. The incidence of twin-twin transfusion syndrome ranges from 5-15% of all twin pregnancies. If this condition develops in the second trimester, it is usually associated with spontaneous abortion and death of one or both fetuses before viability. Developing the syndrome in the third trimester has better perinatal outcome. Mortality rates ranging from 56%-100%, depending on gestational age and severity of the syndrome. The ultrasound criterias for diagnosis, in this study,were the presence of twins of the same sex with discordant growth, with oligohydroamnios in one twin sac and polyhydroamnios in the other one, one placenta and thin membrane between twins. The present study shows clinical course of 14 cases and value of Doppler ultrasound to analyze the usefulness of umbilical artery blood flow velocimetry for predicting the risk of twin-twin transfusion syndrome. 14 twin pregnancies with twin-twin transfusion syndrome were diagnosed during the last four years period and prospectivelly followed. 9 cases were diagnosed before the completion od 28 weeks of gestation.The mean gestational age was 21,6_+4,2 weeks at diagnosis and 23,2+_3,6 weeks at delivery. 5 cases were diagnosed after 28 weeks of gestation. The mean gestational age in this group was 29,6+_2,1 weeks at diagnosis and 33+_3,3 weeks at delivery. The survival rate in this study was 29%(8/28.9 cases ended in spontaneous abortion between 18th and 27th weeks of pregnancy (table 1 and 5 in premature labor (table 2.There were 7 intrauterine death (5 at admission and 2 few days after admission and 13 neonatal deaths

  6. Mitral valve regurgitation in twins

    DEFF Research Database (Denmark)

    Bakkestrøm, Rine; Larsen, Lisbeth Aagaard; Møller, Jacob Eifer

    2016-01-01

    BACKGROUND: Smaller observational studies have suggested familial clustering of mitral regurgitation (MR). Using a large twin cohort, the aims were to assess MR concordance rates and assess mortality in MR twins and unaffected cotwins. METHODS: Through the Danish Twin Registry, twins...... with an International Classification of Diseases, Eighth Revision and Tenth Revision diagnosis code of MR born 1880-1989 were identified and proband-wise concordance rates were calculated. To assess whether having a cotwin with MR affected survival, 10 matched twins without MR (n = 5,575) were selected for each MR twin...... (n = 562), and all-cause mortality rates were assessed. RESULTS: Among the 87,432 twins alive January 1, 1977, or later, 494 (0.57%) MR individuals were identified. Six MR concordant pairs were found, of which 3 were monozygotic. Proband-wise concordance rate when accounting for right censoring...

  7. Muscle free amino acid profiles are related to differences in skeletal muscle growth between single and twin ovine fetuses near term

    OpenAIRE

    Sales, Francisco; Pacheco, David; Blair, Hugh; Kenyon, Paul; McCoard, Sue

    2013-01-01

    Twin sheep fetuses have reduced skeletal muscle weight near birth relative to singles as a result of restricted muscle hypertrophy. Intracellular free amino acids (FAA) are reported to regulate metabolic pathways which control muscle protein accretion, whereby reduced intracellular content of specific FAA may reduce their activation and therefore, muscle hypertrophy. The aim of this study was to determine whether differences in muscle weight between singleton and twin fetuses, under different...

  8. Susceptibility of phagocytes from elk, deer, bighorn sheep, and domestic sheep to Pasteurella haemolytica cytotoxins.

    Science.gov (United States)

    Silflow, R M; Foreyt, W J

    1994-10-01

    Alveolar macrophages and peripheral blood neutrophils from elk (Cervus elaphus), bighorn sheep (Ovis canadensis canadensis), and domestic sheep were exposed to culture supernatants from Pasteurella haemolytica isolated from bighorn sheep and domestic sheep. In a second experiment, peripheral blood neutrophils from mule deer (Odocoileus hemionus), elk, and bighorn sheep were exposed to culture supernatants from P. haemolytica isolated from elk, bighorn sheep and domestic sheep. Alveolar macrophages from elk, bighorn sheep and domestic sheep were resistant to killing by P. haemolytica supernatants from bighorn sheep and domestic sheep; susceptibility of neutrophils to cell death, as measured by release of lactate dehydrogenase, differed significantly (P sheep and domestic sheep neutrophils were susceptible to cytotoxin damage by the P. haemolytica isolates used; bighorn sheep neutrophils were four- to eight-fold more susceptible to cytotoxin damage than domestic sheep neutrophils. Neutrophils from deer and elk were resistant to killing by P. haemolytica cytotoxins from any species tested.

  9. Twin pregnancy in a liver transplant recipient with HIV infection.

    Science.gov (United States)

    Van Schalkwyk, McI; Westbrook, R H; O'Beirne, J; Wright, A; Gonzalez, A; Johnson, M A; Kinloch-de Loës, S

    2016-10-05

    We are not aware of a report detailing the complex obstetrical and medical management of twin pregnancy in the context of HIV infection and early post-liver transplantation period. Here we describe the successful outcome of a twin pregnancy in a 28-year-old HIV-positive female receiving antiretroviral therapy and immunosuppressive therapy who was the recipient of a liver transplant for previous drug-induced liver failure.

  10. Brazilian Twin Registry: A Bright Future for Twin Studies/Twin Research: Twin Study of Alcohol Consumption and Mortality; Oxygen Uptake in Adolescent Twins/In the News: Superfecundated Twins In Vietnam; Adolescent Twin Relations; Twin and Triplet Co-Workers; A Special Twin Ultrasound; Monozygotic Twins With Different Skin Color; Identical Twin Returns from Space.

    Science.gov (United States)

    Segal, Nancy L

    2016-06-01

    The establishment of the Brazilian Twin Registry for the study of genetic, social, and cultural influences on behavior is one of eleven newly funded projects in the Department of Psychology at the University of São Paulo. These 11 interrelated projects form the core of the university's Center for Applied Research on Well-Being and Human Behavior. An overview of the planned twin research and activities to date is presented. Next, two recent twin studies are reviewed, one on the relationship between alcohol consumption and mortality, and the other on factors affecting maximal oxygen uptake. Twins cited in the media include the first identified superfecundated twins in Vietnam, adolescent twin relations, twins and triplets who work together, monozygotic twins with different skin tones and a co-twin control study that addresses the effects of space travel.

  11. Fatal pneumonia of bighorn sheep following association with domestic sheep.

    Science.gov (United States)

    Foreyt, W J; Jessup, D A

    1982-04-01

    During 1979-1980 acute fibrinopurulent bronchopneumonia resulted in high mortality or total loss of herds of bighorn sheep (Ovis canadensis) in California and Washington. Contact with domestic sheep occurred shortly before the onset of disease in each case. Circumstantial evidence indicated that the apparently healthy domestic sheep transmitted pathogenic bacteria to the bighorns, resulting in mortality. Pasteurella multocida and Corynebacterium pyogenes were isolated from pulmonary tissue of dead bighorns. The presence of domestic sheep may have been an important stress which initiated or compounded the disease.

  12. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    2009-01-01

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  13. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  14. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    2009-01-01

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  15. Salmonella in Sheep in Iceland

    Directory of Open Access Journals (Sweden)

    Gunnarsson E

    2002-03-01

    Full Text Available In 1995 several outbreaks of food poisoning in humans occurred in Iceland, that were traced to salmonella contamination of singed sheep heads. This prompted us to study the prevalence of salmonella infection in sheep and to trace where and how infection might have occurred. Faecal, intestinal contents and tonsillar samples were collected in the spring and autumn from sheep on 50 farms in the southwestern part of the country, where salmonellosis had been detected and from 5 farms in the northwestern part of the country. All faecal samples from the southwest were negative, whereas samples from 3 farms obtained in the autumn in the northwest were positive. Tonsillae taken in the autumn were positive in sheep from 3 farms in the southwest and 2 in the northwest. Our results show that salmonella infection is rare in Icelandic sheep but healthy carriers may harbour the bacteria in tonsillae. Salmonella was not detected in drainage from slaughterhouses nor in singed sheep heads.

  16. Vesicular stomatitis virus replicon expressing the VP2 outer capsid protein of bluetongue virus serotype 8 induces complete protection of sheep against challenge infection.

    Science.gov (United States)

    Kochinger, Stefanie; Renevey, Nathalie; Hofmann, Martin A; Zimmer, Gert

    2014-06-13

    Bluetongue virus (BTV) is an arthropod-borne pathogen that causes an often fatal, hemorrhagic disease in ruminants. Different BTV serotypes occur throughout many temperate and tropical regions of the world. In 2006, BTV serotype 8 (BTV-8) emerged in Central and Northern Europe for the first time. Although this outbreak was eventually controlled using inactivated virus vaccines, the epidemic caused significant economic losses not only from the disease in livestock but also from trade restrictions. To date, BTV vaccines that allow simple serological discrimination of infected and vaccinated animals (DIVA) have not been approved for use in livestock. In this study, we generated recombinant RNA replicon particles based on single-cycle vesicular stomatitis virus (VSV) vectors. Immunization of sheep with infectious VSV replicon particles expressing the outer capsid VP2 protein of BTV-8 resulted in induction of BTV-8 serotype-specific neutralizing antibodies. After challenge with a virulent BTV-8 strain, the vaccinated animals neither developed signs of disease nor showed viremia. In contrast, immunization of sheep with recombinant VP5 - the second outer capsid protein of BTV - did not confer protection. Discrimination of infected from vaccinated animals was readily achieved using an ELISA for detection of antibodies against the VP7 antigen. These data indicate that VSV replicon particles potentially represent a safe and efficacious vaccine platform with which to control future outbreaks by BTV-8 or other serotypes, especially in previously non-endemic regions where discrimination between vaccinated and infected animals is crucial.

  17. Reared-Apart Chinese Twins: Chance Discovery/Twin-Based Research: Twin Study of Media Use; Twin Relations Over the Life Span; Breast-Feeding Opposite-Sex Twins/Print and Online Media: Twins in Fashion; Second Twin Pair Born to Tennis Star; Twin Primes; Twin Pandas.

    Science.gov (United States)

    Segal, Nancy L

    2017-04-01

    A January 2017 reunion of 10-year-old reared-apart Chinese twin girls was captured live on ABC's morning talk show Good Morning America, and rebroadcast on their evening news program Nightline. The twins' similarities and differences, and their participation in ongoing research will be described. This story is followed by reviews of twin research concerning genetic and environmental influences on media use, twin relations across the lifespan and the breast-feeding of opposite-sex twins. Popular interest items include twins in fashion, the second twin pair born to an internationally renowned tennis star, twin primes and twin pandas.

  18. Becoming Sheep, Becoming Animal..

    DEFF Research Database (Denmark)

    Grum, Charlotte; Svabo, Connie

    As a part of a 2015 group exhibition exploring the history and local myths of a woman living in a Danish heath landscape 150 years ago, artist Charlotte Grum connected herself to a live sheep for 4 hours a day, 5 days a week, for 5 weeks, turning the two into a hybrid relational assemblage, intra...... of posthuman performance.Engaging with matter and producing knowledge on mattering itself seems to call for multiple mediated modes of dissemination, embodying the complexities of becoming...

  19. Sheep botfly: ophthalmomyiasis externa.

    Science.gov (United States)

    Harvey, J T

    1986-04-01

    Sheep botfly (Oestrus ovis) conjunctival infestation is rare in North America but is common in other parts of the world. The author treated 30 patients with this type of conjunctivitis in Jerusalem in 1981 and 1982. The conjunctivitis may vary from mild to severe (pseudo-orbital cellulitis). Features of the conjunctivitis include pale edema, linear superficial punctate keratopathy and the presence of larvae in the conjunctival sac. Conjunctival scrapings revealed a preponderance of polymorphonucleocytes.

  20. SHEEP TEMPORAL BONE

    Directory of Open Access Journals (Sweden)

    Kesavan

    2016-03-01

    Full Text Available INTRODUCTION Human temporal bones are difficult to procure now a days due to various ethical issues. Sheep temporal bone is a good alternative due to morphological similarities, easy to procure and less cost. Many middle ear exercises can be done easily and handling of instruments is done in the procedures like myringoplasty, tympanoplasty, stapedotomy, facial nerve dissection and some middle ear implants. This is useful for resident training programme.

  1. Minimal Mirror Twin Higgs

    CERN Document Server

    Barbieri, Riccardo; Harigaya, Keisuke

    2016-01-01

    In a Mirror Twin World with a maximally symmetric Higgs sector the little hierarchy of the Standard Model can be significantly mitigated, perhaps displacing the cutoff scale above the LHC reach. We show that consistency with observations requires that the Z2 parity exchanging the Standard Model with its mirror be broken in the Yukawa couplings. A minimal such effective field theory, with this sole Z2 breaking, can generate the Z2 breaking in the Higgs sector necessary for the Twin Higgs mechanism, and has constrained and correlated signals in invisible Higgs decays, direct Dark Matter Detection and Dark Radiation, all within reach of foreseen experiments. For dark matter, both mirror neutrons and a variety of self-interacting mirror atoms are considered. Neutrino mass signals and the effects of a possible additional Z2 breaking from the vacuum expectation values of B-L breaking fields are also discussed.

  2. Emergence of Digital Twins

    OpenAIRE

    Datta, Shoumen Palit Austin

    2016-01-01

    Multiple forms of digital transformation are imminent. Digital Twins represent one concept. It is gaining momentum because it may offer real-time transparency. Rapid diffusion of digital duplicates faces hurdles due to lack of semantic interoperability between architectures, standards and ontologies. The technologies necessary for automated discovery are in short supply. Progression of the field depends on convergence of information technology, operational technology and protocol-agnostic tel...

  3. Nutrition in twin pregnancy.

    Science.gov (United States)

    MacGillivray, I

    1979-01-01

    The urinary nitrogen output appears to be related to both protein and energy intake, so that women having heavier babies probably eat more, although this may simply mean that they are larger women. Women with twin pregnancies have been found to have a lesser urinary nitrogen output, but it seems unlikely that this be due to lower intakes. They might simply utilize their diet more efficiently--a hypothesis that is now being tested.

  4. Tribute to dr louis keith: twin and physician extraordinaire/twin research reports: influences on asthma severity; chimerism revisited; DNA strand break repair/media reports: twins born apart; elevated twin frequencies; celebrity father of twins; conjoined twinning.

    Science.gov (United States)

    Segal, Nancy L

    2014-10-01

    The International Society for Twin Studies has lost a valued friend and colleague. Dr Louis Keith, Emeritus Professor of Obstetrics and Gynecology at Northwestern University, in Chicago, passed away on Sunday, July 6, 2014. His life and work with twins will be acknowledged at the November 2014 International Twin Congress in Budapest, Hungary. Next, twin research reports on the severity of asthma symptoms, a case of chimerism, and factors affecting DNA breakage and repair mechanisms are reviewed. Media reports cover twins born apart, elevated twin frequencies, a celebrity father of twins, and a family's decision to keep conjoined twins together.

  5. Socioeconomic position and twins' health

    DEFF Research Database (Denmark)

    Osler, Merete; McGue, Matt; Christensen, Kaare

    2007-01-01

    of middle-aged Danish twins was conducted in 1998-99. The study population included 1266 like-sex twin pairs [52.5% monozygotic (MZ) and 47.6% dizygotic (DZ)]. Data were obtained on childhood and adult social class and on height, BMI, grip strength, depression symptoms, self-rated health, cognitive function......, prenatal and rearing environmental factors from environmental factor later in life, we compared the health status among male and female twin pairs who lived together during childhood and were discordant or concordant on adult socioeconomic position. METHODS: A cross-sectional survey among a random sample......, physical activity, smoking, alcohol and food intake. RESULTS: The expected associations between the individual twins' adult social class and health measures were observed. Among DZ male twins discordant on adult social class, the higher social class twin was on average significantly taller and had higher...

  6. Twin-to-twin delivery time: neonatal outcome of the second twin.

    Science.gov (United States)

    Schneuber, Susanne; Magnet, Eva; Haas, Josef; Giuliani, Albrecht; Freidl, Thomas; Lang, Uwe; Bjelic-Radisic, Vesna

    2011-12-01

    To examine the effect of twin-to-twin delivery time (TTDT) on neonatal outcome. We evaluated twin deliveries >34 weeks of gestation. Twin pregnancies with both twins delivered by cesarean section and pregnancies with antenatal complications were excluded. We analyzed TTDT and neonatal outcomes of the second twin (umbilical arterial pH value (pH(art)), Apgar scores at 1, 5 and 10 minutes, need for intensive care). The study population was divided into two homogenous groups based on the mode of delivery: (A) vertex presentation and vaginal delivery of both twins, (B) vertex presentation and vaginal or vaginal operative delivery of twin I, breech or transverse presentation and vaginal breech delivery or cesarean section (CS) of twin II. A total of 207 twin pairs were included in our study. In Group A (n = 151) there were no significant correlations between TTDT and pH(art) or Apgar scores at 1,5 and 10 minutes of twin II (p = .156; 0.861; 0.151 and 0.384, respectively). In Group B (n = 56), the mean pH(art) of twin II was inversely correlated to TTDT, but not significantly (p = .417). TTDT was inversely related to 1-min and 5-min Apgar scores, but not significantly (p = .330; p = .138, respectively). The 10-min Apgar score showed no correlation with TTDT (p = .638). Increasing TTDT was not associated with adverse fetal outcome. Expectant management of the second twin appears possible and elapsed time alone does not appear to be an indication for intervention.

  7. Tiotropium bromide suppresses smoke inhalation and burn injury-induced ERK 1/2 and SMAD 2/3 signaling in sheep bronchial submucosal glands.

    Science.gov (United States)

    Jacob, Sam; Zhu, Yong; Asmussen, Sven; Ito, Hiroshi; Herndon, David N; Enkhbaatar, Perenlei; Hawkins, Hal K; Cox, Robert A

    2014-05-01

    The effects of tiotropium bromide on ERK 1/2, SMAD 2/3 and NFκB signaling in bronchial submucosal gland (SMG) cells of sheep after smoke inhalation and burn injury (S + B) were studied. We hypothesized that tiotropium would modify intracellular signaling processes within SMG cells after injury. Bronchial tissues were obtained from uninjured (sham, n = 6), S + B injured sheep 48 h after injury (n = 6), and injured sheep nebulized with tiotropium (n = 6). The percentage (mean ± SD) of cells showing nuclear localization of phosphorylated ERK 1/2, pSMAD 2/3, and NFκB (p65) was determined by immunohistochemistry. Nuclear pERK 1/2 staining was increased in injured animals as compared to sham, (66 ± 20 versus 14 ± 9), p = 0.0022, as was nuclear pSMAD, 84 ± 10 versus 20 ± 10, p = 0.0022. There was a significant decrease in pERK 1/2 labeling in the tiotropium group compared to the injured group (31 ± 20 versus 66 ± 20, p = 0.013), and also a decrease in pSMAD labeling, 62 ± 17 versus 84 ± 10, p = 0.04. A significant increase for NFκB (p65) was noted in injured animals as compared to sham (73 ± 16 versus 7 ± 6, p = 0.0022). Tiotropium-treated animals showed decreased p65 labeling as compared to injured (35 ± 17 versus 74 ± 16, p = 0.02). The decrease in nuclear expression of pERK, pSMAD and NFκB molecules in SMG cells with tiotropium treatment is suggestive that their activation after injury is mediated in part through muscarinic receptors.

  8. Fatal Pasteurella haemolytica pneumonia in bighorn sheep after direct contact with clinically normal domestic sheep.

    Science.gov (United States)

    Foreyt, W J

    1989-03-01

    Six Rocky Mountain bighorn sheep were raised in captivity from birth (n = 5) or taken from the wild as a lamb (n = 1). After the bighorn sheep were in captivity for over a year, 6 clinically normal domestic sheep were placed on the 2 ha of pasture on which the bighorn sheep were kept. Nasal swab specimens were obtained from all sheep at the time the domestic sheep were introduced. Pasteurella haemolytica was isolated from swab specimens obtained from 4 of 6 domestic sheep, but not from specimens obtained from the bighorn sheep. All 6 bighorn sheep died of acute hemorrhagic pneumonia after exposure to domestic sheep. Death in the bighorn sheep occurred on days 4, 27, 27, 29, 36, or 71 after initial exposure to domestic sheep. Pasteurella haemolytica was isolated from respiratory tract tissue specimens of all bighorn sheep at the time of death. None of the domestic sheep were clinically ill during the study. At the end of the study, 3 of 6 domestic sheep were euthanatized, and at necropsy, P haemolytica was isolated from 2 of them. The most common serotypes in bighorn and domestic sheep were P haemolytica T-3 and A-2. Other serotypes isolated included P haemolytica A-1, A-9, and A-11 in bighorn sheep and A-1 in domestic sheep. On the basis of results of this study and of other reports, domestic sheep and bighorn sheep should not be managed in proximity to each other because of the potential fatal consequences in bighorn sheep.

  9. Trojan twin planets

    Science.gov (United States)

    Dvorak, R.; Loibnegger, B.; Schwarz, R.

    2017-03-01

    The Trojan asteroids are moving in the vicinity of the stable Lagrange points L_4 and L_5 of the gas giants Jupiter, Uranus and Neptune. Their motion can be described and understood with the aid of the restricted three-body problem. As an extension of this problem we investigate how stable motion close to the Lagrange points of two massive bodies can exist. This configuration can be described as the Trojan Twin Problem when we regard the two additional bodies as having a mass significantly smaller than the the two primary bodies: a star in the center (m_1) and an additional Jupiter-like mass (m_2). Using this 4-body problem we have undertaken numerical investigations concerning possible stable "twin orbits". However, these two bodies (m_3 and m_4) in Trojan-like orbits may have quite different masses. We decided to choose 6 different scenaria for this problem: as primary body, m2, we have taken a Jupiter-like planet, a Saturn-like one, and a super-Earth with 10 Earthmasses (m_{Earth}) respectively. As quasi twin planets, we have used different mass ratios namely objects for m3 and m4 from 10m_{Earth} to Moon like ones. We found different stable configurations depending on the involved masses and the initial distances between the twins (always close to the Lagrange point). Although the formation of such a configuration seems to be not very probable we should not exclude that it exists regarding the huge number of planets even in our own galaxy. This model is of special interest when the most massive planet (m_2) is moving on an orbit in the habitable zone around a main sequence star. One can use our results of stable orbits of Trojan Twin Planets (or asteroids) for extrasolar systems having as second primary a Jupiter-like, a Saturn-like or a super-Earth like planet around a star similar to our Sun.

  10. Attention bias to threat indicates anxiety differences in sheep.

    Science.gov (United States)

    Lee, Caroline; Verbeek, Else; Doyle, Rebecca; Bateson, Melissa

    2016-06-01

    Humans and animals show increased attention towards threatening stimuli when they are in increased states of anxiety. The few animal studies that have examined this phenomenon, known as attention bias, have applied environmental manipulations to induce anxiety but the effects of drug-induced anxiety levels on attention bias have not been demonstrated. Here, we present an attention bias test to identify high and low anxiety states in sheep using pharmacological manipulation. Increased anxiety was induced using 1-methyl-chlorophenylpiperazine (m-CPP) and decreased anxiety with diazepam, and then we examined the behaviour of sheep in response to the presence of a dog as a threat. Increased attention towards the threat and increased vigilance were shown in sheep that received the m-CPP and reduced in sheep receiving the diazepam. The modulated attention towards a threat displayed by the m-CPP and diazepam animals suggests that attention bias can assess different levels of anxiety in sheep. Measuring attention bias has the potential to improve animal welfare assessment protocols.

  11. When You Are a Twin or Triplet

    Science.gov (United States)

    ... be a twin? Are you a twin and wonder why everyone thinks it's so special? It's fascinating ... the way the egg is fertilized when a woman becomes pregnant . In fraternal twins, two different eggs ...

  12. A case of conjoined twins (thoraco-omphalopygopagus tribrachius tetrapus in lamb

    Directory of Open Access Journals (Sweden)

    Yazdan Mazaheri

    2014-04-01

    Full Text Available Sheep conjoined twins have been reported less than cow. An apparently female conjoined twin lambs was examined based on external and internal features. In radiology, two vertebral columns and two pairs of the ribs were seen. Only two heads and two necks were separated (thoraco-omphalopygopagus. There were three forelimbs (tribrachius, one of which grew on dorsal region as a notomelus. Teat buds of the monsters differed in number. Only one lamb had umbilicus, including one umbilical vein, and two umbilical arteries locating besides one urinary bladder. This lamb had also one uterus. Two-separated alimentary tracts were observed in a common abdomen. Common thorax and abdominal cavities were separated by a diaphragm. There were two esophageal hiatuses, and two caval foramina but only one aortic hiatus. Two pairs of lungs and two unequal and connected hearts in a common pericardium were observed. Abnormality of the circulatory system might have caused the death of the twins.

  13. Breeding Practices in Sheep Farming

    Directory of Open Access Journals (Sweden)

    M.A. Shejal

    2009-02-01

    Full Text Available The sheep is an important economic livestock species, contributing greatly to the Indian economy, especially in arid, semi arid and mountain areas. The current population in world is 1110.78 millions, around 44.85 millions (1987 sheeps in India (ICAR., 2002. Sheeps are mostly reared for meat and wool. The average annual wool production per sheep is between 3.5 to 5.5 kg of fine quality wool in Australia, New Zealand and U.S.S.R., where as in India except Magra sheep which annually yield more than 2 kg wool having staple length 5.8 cm, the average of rest of the wool produced is less than 1.0 kg per sheep of inferior quality (Banerjee G.C., 1998. Therefore many farmers in southern India adapted sheep rearing for meat production than for wool production. For yielding more production from sheep farming one should have sound knowledge of general information related to the reproduction and different breeding practices. [Vet. World 2009; 2(1.000: 43-44

  14. Vaccination delays maedi-visna lentivirus infection in a naturally-infected sheep flock

    Directory of Open Access Journals (Sweden)

    Gudnadóttir Margrét

    2013-01-01

    Full Text Available Abstract Background The Maedi-Visna (MV lentivirus causes two slowly progressive eventually fatal diseases of sheep, Maedi, a progressive interstitial pneumonia, and Visna, a progressive demyelinating disease of the central nervous system. Other lentiviruses also cause fatal slow infections in their natural hosts, e.g. the HIV virus in humans. Results of experimental vaccination against any lentivirus where vaccinees are challenged by natural routes, may therefore be of general interest. From 1991–1998 experiments with formalin-inactivated whole Maedi-Visna virus vaccine were carried out in the Department of Microbiology at the University of Iceland. Western Blot tests showed good immune response to all major proteins of the virus. When aluminium hydroxide was added to the vaccine all vaccinees developed neutralizing antibodies to the vaccine strain at titers 1/8 – 1/256. After housing 5 twin pairs, one twin in each pair vaccinated, the other unvaccinated, with infected sheep for 4 years, all the unvaccinated twins became infected, but only 2 of their vaccinated siblings as confirmed by virus cultivation experiments on tissues from their lungs spleens lymph nodes and choroid plexuses. Results One twin in each of 40 female twin pairs, born into a Maedi-Visna-infected sheep flock and kept under natural farming conditions in Cyprus, was vaccinated at birth, 3 weeks and 3 months, with formalin-inactivated whole Maedi-Visna lentivirus vaccine adjuvanted with aluminium hydroxide. 17 mothers of the twins were seronegative, 13 seroconverting and 10 had old infection. Of 17 vaccinees born to seronegative mothers 9 were uninfected at 28 months, but only 2 of their unvaccinated siblings. Of 13 unvaccinated twins born to seroconverting mothers, 12 caught infection during their first 10 weeks, but only 4 of their vaccinated siblings. Vaccination had no effects on 10 vaccinees born to mothers with long-standing Maedi-Visna infections and broad andibody

  15. Contemporary management of complicated monochorionic twins.

    Science.gov (United States)

    Moise, Karen Y; Kugler, Lisa; Jones, Tyra

    2012-01-01

    Monochorionic twins are at increased risk for unique complications including twin-twin transfusion syndrome (TTTS), selective intrauterine growth restriction (sIUGR), and twin-reversed arterial perfusion (TRAP) sequence. Twin-twin transfusion syndrome is treated with laser photocoagulation whereas selective reduction is an option in previable sIUGR or TRAP sequence. The nurse is integral in the management, education, care and support of women with complicated pregnancies. © 2012 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  16. Twinning across the Developing World.

    Directory of Open Access Journals (Sweden)

    Jeroen Smits

    Full Text Available BACKGROUND: Until now, little was known about the variation in incidence of twin births across developing countries, because national representative data was lacking. This study provides the first comprehensive overview of national twinning rates across the developing world on the basis of reliable survey data. METHODS: Data on incidence of twinning was extracted from birth histories of women aged 15-49 interviewed in 150 Demographic and Health Surveys, held between 1987 and 2010 in 75 low and middle income countries. During the interview, information on all live births experienced by the women was recorded, including whether it was a singleton or multiple birth. Information was available for 2.47 million births experienced by 1.38 million women in a period of ten years before the interview. Twinning incidence was measured as the number of twin births per thousand births. Data for China were computed on the basis of published figures from the 1990 census. Both natural and age-standardized twinning rates are presented. RESULTS/CONCLUSIONS: The very low natural twinning rates of 6-9 per thousand births previously observed in some East Asian countries turn out to be the dominant pattern in the whole South and South-East Asian region. Very high twinning rates of above 18 per thousand are not restricted to Nigeria (until now seen as the world's twinning champion but found in most Central-African countries. Twinning rates in Latin America turn out to be as low as those in Asia. Changes over time are small and not in a specific direction. SIGNIFICANCE: We provide the most complete and comparable overview of twinning rates across the developing world currently possible.

  17. Twinning and heteropaternity in chimpanzees (Pan troglodytes).

    Science.gov (United States)

    Ely, John J; Frels, William I; Howell, Sue; Izard, M Kay; Keeling, Michale E; Lee, D Rick

    2006-05-01

    Unlike monozygotic (MZ) twins, dizygotic (DZ) twins develop from separate ova. The resulting twins can have different sires if the fertilizing sperm comes from different males. Routine paternity testing of a pair of same-sexed chimpanzee twins born to a female housed with two males indicated that the twins were sired by two different males. DNA typing of 22 short-tandem repeat (STR) loci demonstrated that these twins were not MZ twins but heteropaternal DZ twins. Reproductive data from 1926-2002 at five domestic chimpanzee colonies, including 52 twins and two triplets in 1,865 maternities, were used to estimate total twinning rates and the MZ and DZ components. The average chimpanzee MZ twinning rate (0.43%) equaled the average human MZ rate (0.48%). However, the chimpanzee DZ twinning rate (2.36%) was over twice the human average, and higher than all but the fertility-enhanced human populations of Nigeria. Similarly high twinning rates among African chimpanzees indicated that these estimates were not artifacts of captivity. Log-linear analyses of maternal and paternal effects on recurrent twinning indicated that females who twinned previously had recurrence risks five times greater than average, while evidence for a paternal twinning effect was weak. Chimpanzee twinning rates appear to be elevated relative to corresponding estimated human rates, making twinning and possibly heteropaternity more important features of chimpanzee reproductive biology than previously recognized.

  18. Twin Legacies: Victor and Vincent McKusick/Twin Studies: Twinning Rates I; Twinning Rates II; MZ Twin Discordance for Russell-Silver Syndrome; Twins' Language Skills/Headlines: Babies Born to Identical Twin Couples; Identity Exchange; Death of Princess Ashraf (Twin); Yahoo CEO Delivers Identical Twins.

    Science.gov (United States)

    Segal, Nancy L

    2016-04-01

    The lives of the illustrious monozygotic (MZ) twins, Victor A. and Vincent L. McKusick, are described. Victor earned the distinction as the 'Father of Medical Genetics', while Vincent was a legendary Chief Justice of the Maine Supreme Court. This dual biographical account is followed by two timely reports of twinning rates, a study of MZ twin discordance for Russell-Silver Syndrome (RSS) and a study of twins' language skills. Twin stories in the news include babies born to identical twin couples, a case of switched identity, the death of Princess Ashraf (Twin) and a new mother of twins who is also Yahoo's CEO.

  19. Estimating twin concordance for bivariate competing risks twin data

    DEFF Research Database (Denmark)

    Scheike, Thomas Harder; Holst, Klaus Kähler; von Bornemann Hjelmborg, Jacob

    2014-01-01

    For twin time-to-event data, we consider different concordance probabilities, such as the casewise concordance that are routinely computed as a measure of the lifetime dependence/correlation for specific diseases. The concordance probability here is the probability that both twins have experienced...... over time, and covariates may be further influential on the marginal risk and dependence structure. We establish the estimators large sample properties and suggest various tests, for example, for inferring familial influence. The method is demonstrated and motivated by specific twin data on cancer...... the event of interest. Under the assumption that both twins are censored at the same time, we show how to estimate this probability in the presence of right censoring, and as a consequence, we can then estimate the casewise twin concordance. In addition, we can model the magnitude of within pair dependence...

  20. Deformation twinning in small-sized face-centred cubic single crystals: Experiments and modelling

    Science.gov (United States)

    Liang, Z. Y.; Huang, M. X.

    2015-12-01

    Small-sized crystals generally show deformation behaviour distinct from their bulk counterparts. In addition to dislocation slip, deformation twinning in small-sized face-centred cubic (FCC) single crystals has been reported to follow a different mechanism which involves coherent emission of partial dislocations on successive { 111 } planes from free surface. The present work employed a twinning-induced plasticity (TWIP) steel with a low stacking fault energy to systematically investigate the twin evolution in small-sized FCC single crystals. Micrometre-sized single crystal pillars of TWIP steel were fabricated by focus ion beam and then strained to different levels by compression experiments. Detailed transmission electron microscopy characterization was carried out to obtain a quantitative evaluation of the deformation twins, which contribute to most of the plastic strain. Emissions of partial dislocations from free surface (surface sources) and pre-existing perfect dislocations inside the pillar (inner sources) are found as the essential processes for the formation of deformation twins. Accordingly, a physically-based model, which integrates source introduction methods and source activation criterions for partial dislocation emission, is developed to quantitatively predict the twin evolution. The model is able to reproduce the experimental twin evolution, in terms of the total twin formation, the twin morphology and the occurrence of twinning burst.

  1. Holographic twin Higgs model.

    Science.gov (United States)

    Geller, Michael; Telem, Ofri

    2015-05-15

    We present the first realization of a "twin Higgs" model as a holographic composite Higgs model. Uniquely among composite Higgs models, the Higgs potential is protected by a new standard model (SM) singlet elementary "mirror" sector at the sigma model scale f and not by the composite states at m_{KK}, naturally allowing for m_{KK} beyond the LHC reach. As a result, naturalness in our model cannot be constrained by the LHC, but may be probed by precision Higgs measurements at future lepton colliders, and by direct searches for Kaluza-Klein excitations at a 100 TeV collider.

  2. Oliver Sacks: Our Correspondence About Twins/Twin Research: Vanishing Twins Syndrome; Discordant Sex in MZ Twins; Pregnancy Outcomes in IVF and ICSI Conceived Twins/Print and Media: Superfetated Twins; Twins Discordant for Smoking; Twins in Fashion; Yale University Twin Hockey Players; Conjoined Twin-Visiting Professor.

    Science.gov (United States)

    Segal, Nancy L

    2017-08-01

    The late neurologist and author, Oliver Sacks, published an insightful 1986 review of Marjorie Wallace's book, The Silent Twins, in the New York Times. Taking exception to his assertion about Sir Francis Galton, I wrote a letter to the Times' editor. The letter was unpublished, but it brought a wonderful response from Sacks himself that is reproduced and examined. Next, brief reviews of twin research concerning the vanishing twin syndrome (VTS), discordant sex in a monozygotic (MZ) twin pair, and multiple pregnancy outcomes from assisted reproductive technology (ART) are presented. This section is followed by popular coverage of superfetated twins, smoking-discordant co-twins, twins in fashion, Yale University twin hockey players, and a visiting professor who was a conjoined twin.

  3. Transformation: From Twin to Individual

    Science.gov (United States)

    Magagna, Jeanne

    2007-01-01

    This article explores some of the complexities of psychotherapy with an identical twin. The difficulty of developing in psychotherapy while so much of what is oneself is located in the other twin will also be explored. The use of the countertransference as a therapeutic method will be considered as the young person develops her unique, separate…

  4. Twin Studies of Atopic Dermatitis

    DEFF Research Database (Denmark)

    Elmose, Camilla; Thomsen, Simon Francis

    2015-01-01

    Aim. The aim of this study was to conduct a systematic review of population-based twin studies of (a) the concordance and heritability of AD and (b) the relationship between AD and asthma and, furthermore, to reinterpret findings from previous twin studies in the light of the emerging knowledge a...

  5. Twin methodology in epigenetic studies

    DEFF Research Database (Denmark)

    Tan, Qihua; Christiansen, Lene; von Bornemann Hjelmborg, Jacob

    2015-01-01

    Since the final decades of the last century, twin studies have made a remarkable contribution to the genetics of human complex traits and diseases. With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis ...

  6. Twin Higgs WIMP Dark Matter

    CERN Document Server

    García, Isabel García; March-Russell, John

    2015-01-01

    Dark matter (DM) without a matter asymmetry is studied in the context of Twin Higgs (TH) theories in which the LHC naturalness problem is addressed. These possess a twin sector related to the Standard Model (SM) by a (broken) $\\mathbb{Z}_2$ symmetry, and interacting with the SM via a specific Higgs portal. We focus on the minimal realisation of the TH mechanism, the Fraternal Twin Higgs, with only a single generation of twin quarks and leptons, and $SU(3)'\\times SU(2)'$ gauge group. We show that a variety of natural twin-WIMP DM candidates are present (directly linked to the weak scale by naturalness), the simplest and most attractive being the $\\tau^\\prime$ lepton with a mass $m_{\\tau^\\prime} > m_{\\rm Higgs}/2$, although spin-1 $W^{\\prime\\pm}$ DM and multicomponent DM are also possible (twin baryons are strongly disfavoured by tuning). We consider in detail the dynamics of the possibly (meta)stable glueballs in the twin sector, the nature of the twin QCD phase transition, and possible new contributions to th...

  7. A Computational Discriminability Analysis on Twin Fingerprints

    Science.gov (United States)

    Liu, Yu; Srihari, Sargur N.

    Sharing similar genetic traits makes the investigation of twins an important study in forensics and biometrics. Fingerprints are one of the most commonly found types of forensic evidence. The similarity between twins’ prints is critical establish to the reliability of fingerprint identification. We present a quantitative analysis of the discriminability of twin fingerprints on a new data set (227 pairs of identical twins and fraternal twins) recently collected from a twin population using both level 1 and level 2 features. Although the patterns of minutiae among twins are more similar than in the general population, the similarity of fingerprints of twins is significantly different from that between genuine prints of the same finger. Twins fingerprints are discriminable with a 1.5%~1.7% higher EER than non-twins. And identical twins can be distinguished by examine fingerprint with a slightly higher error rate than fraternal twins.

  8. Dramatically different dizygotic twins: will we include them in Research? Twin research reviews: congenital anomalies, mirror-image effects in conjoined twins, older mothers of twins; Twin statistics: 'Massachusetts, land of twins'; Tribute: Dr Victor A. McKusick.

    Science.gov (United States)

    Segal, Nancy L

    2008-10-01

    The increased frequency of interracial marriage is a likely source of unusual-looking dizygotic (DZ) twins. Some members of DZ twin pairs born to mixed-race couples inherit very different physical features from their parents. This raises several questions, such as: Will researchers wish to include such twins in their ongoing studies? Next, new twin research concerned with congenital anomalies, mirror-image effects in conjoined twins and older mothers of twins will be reviewed. New statistics on twinning rates in Massachusetts will also be summarized, followed by a tribute to the late medical geneticist Dr. Victor A. McKusick.

  9. Identification of smallholder farmers and pastoralists' preferences for sheep breeding traits: choice model approach.

    Science.gov (United States)

    Duguma, G; Mirkena, T; Haile, A; Okeyo, A M; Tibbo, M; Rischkowsky, B; Sölkner, J; Wurzinger, M

    2011-12-01

    Identification of breeding objective traits pertinent to specific production environments with the involvement of target beneficiaries is crucial to the success of a breed improvement program. A choice experiment was conducted in four locations representing different production systems and agro-ecologies that are habitat to four indigenous sheep breeds (Afar, Bonga, Horro and Menz) of Ethiopia with the objective of identifying farmers'/pastoralists' preferences for sheep breeding traits. Following a synthesis of secondary information and diagnostic surveys, two communities per location consisting of 60 households each having at least four breeding ewes were identified. Producers' priority attributes used in the choice sets were identified through in-depth production system studies conducted from December 2007 to March 2008. On the basis of prior information, four to seven attributes were used to design choice sets with different profiles in order to capture results that mimic real life of the different communities. The attributes and levels chosen for the sheep profile were as follows: body size (large/small), coat color (brown/white/black), tail type (good/bad) for both rams and ewes; horn (polled/horned) and libido (active/poor) for rams; and lambing interval (three lambings in 2 years/two lambings in 2 years time), mothering ability (good mother/bad mother), twinning rate (twin bearer/single bearer) and milk yield (two cups per milking/one cup per milking) for ewes. A fractional factorial design was implemented to construct the alternatives included in the choice sets. The design resulted in a randomized selection of 48 sheep profiles (24 sets) for both sexes, which were grouped into four blocks with six choice sets each. An individual respondent was presented with one of the four blocks to make his/her choices. Results indicate that producers' trait preferences were heterogeneous except for body size in rams and mothering ability in ewes where nearly

  10. [Hereditary phaeochromocytoma in twins].

    Science.gov (United States)

    Tóth, Géza; Patócs, Attila; Tóth, Miklós

    2016-08-01

    Phaeochromocytoma is a tumor of the catecholamine-producing cells of the adrenal gland. Extraadrenal phaeochromocytomas are frequently called paragangliomas. The majority of phaeochromocytomas are sporadic, however, about 25-30% are caused by genetic mutation. These tumor are frequently referred as hereditary phaeochromocytomas/paragangliomas. Their incidence increases continuously which can be attributed to availability of genetic examination and to the discovery of novel genes. The 47-year-old female patient underwent abdominal computed tomography which revealed bilateral adrenal gland enlargement. Abdominal magnetic resonance imaging, the 131-I- metaiodobenzylguanidine scintigraphy, urinary catecholamines and serum chomogranin A measurements confirmed the diagnosis of bilateral phaeochromocytomas. The genetically identical twin sister of the patient was also diagnosed with hormonally active bilateral phaechromocytoma, suggesting the genetic origin of phaeochromocytoma. Mutation screening confirmed a germline mutation of the transmembrane protein 127 tumorsupressor gene in both patients. Both patients underwent cortical-sparing adrenalectomy. The adrenal gland with the larger tumor was totally resected, while in the opposite side only the tumor was resected and a small part of the cortex was saved. After the operation urinary catecholamines and serum chromogranin A returned to normal in both patients. Adrenocortical deficiency was absent in the first patient, but her sister developed adrenal insufficiency requiring glucocorticoid replacement. To the best of the authors' knowledge phaeochromocytoma affecting twins has never been described earlier. Genetic examination performed in siblings confirmed the presence of the mutant gene through four generations. Orv. Hetil., 2016, 157(33), 1326-1330.

  11. ANTIPARASITICAL PROTECTION IN SHEEP FARMS

    Directory of Open Access Journals (Sweden)

    DOINA ARDELEANU

    2013-12-01

    Full Text Available Through our researches were carried out at ICDCOC- Palas, Constantza, we proposed ourselves to establish the poly-parasitism structure on sheep, as well as elaborating efficientical methods for anti-parasitical prophylaxis and fighting in sheep populations and pasture sourfaces, in order to ensuring anti-parasitical protection in sheep exploitations The copro-parasitological examinations was carried ovoscopicaly (flotation - by Willis and Mc. Master methods; sediment – by polyvalent method and larvoscopicaly – by Baermann method. The parasitological examination of coprological smears which were harvested on sheep showed the presence of polyparasitism phenomenon with protozoans (coccidiae: Eimeria spp. and helmints (cestodae: Moniesia expansa; gastro-intestinal nemathodes: Trichostrongylus spp., Nematodirus spp., Strongyloides papillosus and pulmonary nemathodes: Müellerius capillaris, Protostrongylus rufescens, Dictyocaulus filaria. Also, we proposed ourselves to study the paresites and their intermediary stages on pastures which were exploited with sheep, comparatively with mowed pastures. In the ansamble of research activities a special place is occupied by testing differents methods, in order to prevention and fighting of parasitical infestations on sheep and pasture in sheep farms.

  12. Estrus synchronization in sheep with synthetic progestagens.

    Science.gov (United States)

    Awel, Hayatu; Eshetu, Lisanework; Tadesse, Gebrehiwot; Birhanu, Alemselam; Khar, S K

    2009-10-01

    Sixteen female sheep of Degua breed were assigned to receive either the full dose of norgestomet ear implant and injectable solution containing norgestomet and estradiol valerate (n = 8) or half the dose (n = 8). The ear implants were removed in both groups on day 12. All ewes received an intramuscular administration of 500 IU PMSG at implant withdrawal. Synchronized ewes were individually hand mated twice at 48 and 60 hours after implant removal. One ewe in each group however refused mating on both occasions. Pregnancy diagnosis was conducted by bimanual external palpation 90 to 100 days post mating. The conception rates (3/7, 42.85%) and (5/7, 71.42%) were recorded in the two treatment groups, respectively. All eight ewes lambed between 145 to 153 days post mating. In group I ewes carried only singletons (prolificity rate 1.0) whereas in group II two ewes delivered twins, producing 7 lambs with prolificity rate of 1.4 (N.S). From this preliminary investigation it appears that the lower dose of norgestomet ear implants offers better option for estrus synchronization accompanied by higher fertility.

  13. Dopamine treatment during acute hypoxia is neuroprotective in the developing sheep brain.

    Science.gov (United States)

    Brew, N; Azhan, A; den Heijer, I; Boomgardt, M; Davies, G I; Nitsos, I; Miller, S L; Walker, A M; Walker, D W; Wong, F Y

    2016-03-01

    Dopamine is often used to treat hypotension in preterm infants; these infants are at risk of developing brain injury due to impaired autoregulation and cerebral hypoperfusion. However the effects of dopamine on the immature brain under conditions of cerebral hypoxia are not known. We hypothesized that pretreatment with dopamine would protect the immature brain from injury caused by cerebral hypoxia. Preterm fetal sheep were used to determine the effects of intravenous dopamine on hypoxia-induced brain injury. In 16 pregnant sheep at 90days of gestation (0.6 of term, term=147days) catheters were implanted aseptically into the fetal carotid artery and jugular vein; an inflatable occluder was placed loosely around the umbilical cord for later induction of fetal hypoxemia. At 5days after surgery, dopamine (10μg/kg/min, n=7 fetuses) or saline (n=9 fetuses) was infused for 74h. Two hours after commencing the dopamine/saline infusion, we induced umbilical cord occlusion (UCO) for up to 25min to produce fetal asphyxia. Fetuses were allowed to recover, and brains were collected 72h later for assessment of neuropathology. Un-operated twin fetuses were used as age-matched non-UCO controls (n=8). In UCO+saline fetuses, microglial and apoptotic cell density in the subcortical and periventricular white matter, caudate nucleus and hippocampus was greater than that in age-matched controls; oxidative stress was elevated in the subcortical and periventricular white matter and caudate nucleus compared to that in age-matched controls. In UCO+dopamine fetuses microglial density and oxidative stress in the cerebral white matter and caudate nucleus were not different to that of age-matched controls. Apoptotic cell death was decreased in the cerebral white matter of UCO+dopamine brains, relative to UCO+saline brains. We conclude that pretreatment with dopamine does not exacerbate hypoxia-induced injury in the immature brain and may be neuroprotective because it led to decreased apoptosis

  14. [BPO-Specific, complement-dependant cell-lysis of differently sensitized sheep red cells: evaluation of haptenic groups and their influence on IgM and IgG-induced lysis (author's transl)].

    Science.gov (United States)

    Wiedermann, G; Stemberger, H; Förster, O; Müller, M

    1976-04-01

    Sheep erythrocytes were coated with bencylpenicilloyl-(BPO)groups. Different incubation periods resulted in erythrocyte preparations with different hapten density. Complement dependent lysis induced by IgM or IgG antibodies was studied with the cell preparations. The calculation of hapten density on the erythrocyte surface was not possible by direct measurement of coupled radioactive BPO since more than 90% of radioactive material was found in the soluble supernatant after osmotic cell lysis and less than 10% was fixed to the cellular membrane. Measurement of membrane bound immunologically relevant BPO-groups was achieved, therefore, by comparison of the inhibitory capacity of the test cells with that of a standard cell preparation. The latter consisted of tannic acid treated erythrocytes coated with protein complexed radioactive BPO. Surface hapten density of the different target cell preparations varied between 1.9 x 10(5) and 4.8 10(5) BPO-groups per cell depending on the time of incubation. Complement dependent antibody mediated cell lysis was significantly reduced by reduction of haptenic sites per target cell, IgG induced lysis being much more affected than hemolysis induced by IgM antibodies. Statistical calculations led to the conclusion that 18,000 protein islets per cell bearing 4 or more BPO-groups are not sufficient for hemolysis induced by IgG antibodies. 48,000 protein islets with this hapten density are necessary for "optimal" sensitization. IgG antibodies must be apparently bound to the cell surface in bivalent form.

  15. Twins and Kindergarten Separation: Divergent Beliefs of Principals, Teachers, Parents, and Twins

    Science.gov (United States)

    Gordon, Lynn Melby

    2015-01-01

    Should principals enforce mandatory separation of twins in kindergarten? Do school separation beliefs of principals differ from those of teachers, parents of twins, and twins themselves? This survey questioned 131 elementary principals, 54 kindergarten teachers, 201 parents of twins, and 112 twins. A majority of principals (71%) believed that…

  16. Paternal age and telomere length in twins

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Mangino, Massimo

    2015-01-01

    . Based on two independent (discovery and replication) twin studies, comprising 889 twin pairs, we show an increase in the resemblance of leukocyte telomere length between dizygotic twins of older fathers, which is not seen in monozygotic twins. This phenomenon might result from a paternal age...

  17. Recipient twin limb ischemia with postnatal onset.

    Science.gov (United States)

    Broadbent, Roland Spencer

    2007-02-01

    After the occurrence of 3 local cases of limb ischemia in newborn twins, we reviewed the literature to investigate this combination systematically. This review reveals a distinct condition: postnatal onset limb ischemia affecting recipient twins in twin-twin transfusion syndrome.

  18. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

    The children's book "Two Is for Twins" celebrates twins and illustrates the many "twos" in a child's world. The uniqueness of twos does not have to mean separate classrooms for twins in child development programs, preschool, or elementary school settings. With recent dramatic increases in the US twin population, how should educators address the…

  19. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

    The children's book "Two Is for Twins" celebrates twins and illustrates the many "twos" in a child's world. The uniqueness of twos does not have to mean separate classrooms for twins in child development programs, preschool, or elementary school settings. With recent dramatic increases in the US twin population, how should educators address the…

  20. Twin Higgs Asymmetric Dark Matter.

    Science.gov (United States)

    García García, Isabel; Lasenby, Robert; March-Russell, John

    2015-09-18

    We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20  GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors.

  1. Twin methodology in epigenetic studies.

    Science.gov (United States)

    Tan, Qihua; Christiansen, Lene; von Bornemann Hjelmborg, Jacob; Christensen, Kaare

    2015-01-01

    Since the final decades of the last century, twin studies have made a remarkable contribution to the genetics of human complex traits and diseases. With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis of diseases to molecular phenotypes in functional genomics especially in epigenetics, a thriving field of research that concerns the environmental regulation of gene expression through DNA methylation, histone modification, microRNA and long non-coding RNA expression, etc. The application of the twin method to molecular phenotypes offers new opportunities to study the genetic (nature) and environmental (nurture) contributions to epigenetic regulation of gene activity during developmental, ageing and disease processes. Besides the classical twin model, the case co-twin design using identical twins discordant for a trait or disease is becoming a popular and powerful design for epigenome-wide association study in linking environmental exposure to differential epigenetic regulation and to disease status while controlling for individual genetic make-up. It can be expected that novel uses of twin methods in epigenetic studies are going to help with efficiently unravelling the genetic and environmental basis of epigenomics in human complex diseases.

  2. The vector-like twin Higgs

    Science.gov (United States)

    Craig, Nathaniel; Knapen, Simon; Longhi, Pietro; Strassler, Matthew

    2016-07-01

    We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models.

  3. The Vector-like Twin Higgs

    CERN Document Server

    Craig, Nathaniel; Longhi, Pietro; Strassler, Matthew

    2016-01-01

    We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models.

  4. Fivefold twinned boron carbide nanowires.

    Science.gov (United States)

    Fu, Xin; Jiang, Jun; Liu, Chao; Yuan, Jun

    2009-09-01

    Chemical composition and crystal structure of fivefold twinned boron carbide nanowires have been determined by electron energy-loss spectroscopy and electron diffraction. The fivefold cyclic twinning relationship is confirmed by systematic axial rotation electron diffraction. Detailed chemical analysis reveals a carbon-rich boron carbide phase. Such boron carbide nanowires are potentially interesting because of their intrinsic hardness and high temperature thermoelectric property. Together with other boron-rich compounds, they may form a set of multiply twinned nanowire systems where the misfit strain could be continuously tuned to influence their mechanical properties.

  5. Seroprevalence of ovine progressive pneumonia virus in sheep in the United States as assessed by analyses of voluntarily submitted samples.

    Science.gov (United States)

    Cutlip, R C; Lehmkuhl, H D; Sacks, J M; Weaver, A L

    1992-06-01

    Ovine progressive pneumonia (OPP) is a lentivirus-induced disease of sheep in the United States that is similar, if not identical, to maedi/visna in many other countries. Prevalence estimates of seropositivity to this virus in sheep in the United States have been confined to limited groups or flocks of sheep and have varied from 1 to 90%. In this study of detection of antibodies against OPP virus, we found a lower general prevalence of antibodies to OPP virus in sheep than was previously reported. Of 16,827 sheep from 29 states in the United States, 26% were seropositive and 48% of 164 flocks that were tested had 1 or more seropositive sheep. Seropositivity to OPP virus for sheep within special categories was determined, although nonrandom samples that were available may have biased the results. Within regions of the United States, prevalence was highest in the Rocky Mountain region at 49% and lowest in the northern Atlantic region at 9%. Seropositive sheep were not evenly distributed among flocks, but were clustered in a few flocks of sheep. A high number of flocks had no or few seropositive sheep. Prevalence increased with age from 4% at less than 1 year to a plateau of 34% at 4 years. Seropositivity was variable among breeds and was not associated with sex, wool class, or place of origin of ancestors.

  6. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the devel

  7. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the

  8. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the devel

  9. Simultaneous Intussusception in Monozygotic Twins

    Directory of Open Access Journals (Sweden)

    Mete Kaya

    2014-12-01

    Full Text Available In this case report, it was aimed to present the simultaneously occurring intussusception in the monozygotic twins. In addition to genetic predisposition, environmental factors has been hypothesized to be responsible for the development of the disease.

  10. Discordant Epilepsy in Monozygous Twins

    OpenAIRE

    2001-01-01

    Twelve monozygotic twins, discordant for epilepsy, were analysed for nonhereditary etiological factors by clinical history, MRI, and quantitative brain volume studies at the Brain Research Institute, University of Melbourne, Victoria, Australia.

  11. Parametric-Resonance Ionization Cooling in Twin-Helix.

    Energy Technology Data Exchange (ETDEWEB)

    V.S. Morozov, Ya.S. Derbenev, A. Afanasev, R.P. Johnson, Erdelyi. B., J.A. Maloney

    2011-09-01

    Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a highluminosity muon collider. For the implementation of PIC, we developed an epicyclic twin-helix channel with correlated optics. Wedge-shaped absorbers immediately followed by short rf cavities are placed into the twin-helix channel. Parametric resonances are induced in both planes using helical quadrupole harmonics. We demonstrate resonant dynamics and cooling with stochastic effects off using GEANT4/G4beamline. We illustrate compensation of spherical aberrations and benchmark COSY Infinity, a powerful tool for aberration analysis and compensation.

  12. Strain-controlled thermal conductivity in ferroic twinned films

    Science.gov (United States)

    Li, Suzhi; Ding, Xiangdong; Ren, Jie; Moya, Xavier; Li, Ju; Sun, Jun; Salje, Ekhard K. H.

    2014-09-01

    Large reversible changes of thermal conductivity are induced by mechanical stress, and the corresponding device is a key element for phononics applications. We show that the thermal conductivity κ of ferroic twinned thin films can be reversibly controlled by strain. Nonequilibrium molecular dynamics simulations reveal that thermal conductivity decreases linearly with the number of twin boundaries perpendicular to the direction of heat flow. Our demonstration of large and reversible changes in thermal conductivity driven by strain may inspire the design of controllable thermal switches for thermal logic gates and all-solid-state cooling devices.

  13. Attention bias to threat indicates anxiety differences in sheep

    OpenAIRE

    2016-01-01

    Humans and animals show increased attention towards threatening stimuli when they are in increased states of anxiety. The few animal studies that have examined this phenomenon, known as attention bias, have applied environmental manipulations to induce anxiety but the effects of drug-induced anxiety levels on attention bias have not been demonstrated. Here, we present an attention bias test to identify high and low anxiety states in sheep using pharmacological manipulation. Increased anxiety ...

  14. The Qingdao Twin Registry: a status update.

    Science.gov (United States)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng; Wang, Shaojie; Zhang, Dong; Tan, Qihua; Tian, Xiaocao; Pang, Zengchang

    2013-02-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes using twin modeling and genome-wide association analysis. Cross-cultural collaborative studies have been carried out between China, Denmark, Finland, and US cohorts. Ongoing data collection and analysis for the Qingdao Twin Registry will be discussed in this article.

  15. Twin stability in highly nanotwinned Cu under compression, torsion and tension

    DEFF Research Database (Denmark)

    Hodge, A.M.; Furnish, T.A.; Shute, C.J.;

    2012-01-01

    Twin stability under four distinct mechanical loading states has been investigated for highly nanotwinned Cu containing parallel nanotwins 40 nm thick. Observed deformation-induced microstructural changes under tension, compression, tension–tension fatigue and torsion are qualitatively compared...

  16. Differential Proteomic Analysis of Carbon Ion Radiation in Sheep Sperm

    Institute of Scientific and Technical Information of China (English)

    HE Yu-xuan; LI Hong-yan; ZHANG Yong; HE Jian-hua; ZHANG Hong; ZHAO Xing-xu

    2013-01-01

    This study is first to investigate proteomic changes in sheep sperm induced by carbon ion radiation using two-dimensional electrophoresis (2-DE) analysis in the project of breeding a new variety of sheep. Differential expression proteins were detected using the PDQuest 8.0 software after staining with Coomassie blue. Valid spots were then analyzed through liquid chromatography tandem mass spectrometry (LC-MS/MS). Among the 480 total protein spots displayed in 2-D gels, 6 specific protein spots were observed in sperm gels. A search against protein sequences in the National Center for Biotechnology Information databases (NCBI) indicated that differentially expressed proteins correspond to two proteins, identified to be enolase and transcription factor AP-2-alpha (TFAP-2α). The two proteins were up-regulated in the irradiated sperm. To the best of our knowledge, this study is the first to identify proteomic changes induced by carbon ion radiation in sheep sperm. The analysis of differential expression protein may be useful in identifying new breeding markers in sheep reproduction and in clarifying the mechanisms involved in irradiation or space breeding.

  17. Detection of Chlamydophila abortus in Sheep (Ovis aries in Mexico

    Directory of Open Access Journals (Sweden)

    Juan M. Jiménez-Estrada

    2008-01-01

    Full Text Available Chlamydophila abortus is one of the pathogens which induce abortion in small ruminants; this pathogen has a tropism for ruminant placenta and causes the disease commonly referred to as Ovine Enzootic Abortion (OEA. In Europe are estimated economic losses of around 20 million pounds a year by OEA. In the American Continent the disease has been reported only in Canada, the United States, Colombia and Chile while in Mexico it is unknown whether OEA is common and it is causing abortions in flocks of sheep from “Estado de Mexico”. The objective of this study was investigating the prevalence of anti-Chlamydophila abortus IgG antibodies and detection of C. abortus DNA in sheep with clinical abort history by mean of ELISA assay (C. abortus ELISA, Institute Pourquier, Montpellier, France and molecular identification of the principal outer membrane protein (POMP 90-91B gene by PCR, respectively. A cross-sectional study was carried out to enroll and random sample of ewes from november 2003 until march 2005. A total of 349 sera and vaginal swabs samples were collected from 35 flocks of sheep from Xalatlaco. The results showed that the seropositive rate was 31.1% (14/45 for healthy and 21.3% (65/304 for sheep with history clinical of abort. In vaginal swabs, the PCR showed 0% (0/45 for healthy animals and 0.65% (2/304 for aborted sheep. Samples from the lungs and liver of the fetus of one of these animals were also positive for C. abortus. In conclusion, these results confirmed that infection with C. abortus is common and is affecting sheep flocks in the Mexican highlands. Therefore, is necessary that the authorities responsible for animal welfare in Mexico (SAGARPA to set up appropriate epidemiological surveillance and control programs to eradicate this disease.

  18. Becoming Sheep, Becoming Animal

    DEFF Research Database (Denmark)

    Grum, Charlotte; Svabo, Connie

    2016-01-01

    Proposal for Performance Research, in response to the call Turning Animal: As a part of a 2015 group exhibition exploring the history and local myths of a woman living in a Danish heath landscape 150 years ago, artist Charlotte Grum connected herself to a live sheep for 4 hours a day, 5 days a we...... support the written account – together with graphic figurations of the many human and non-human actors playing a part of the mattering of “Becoming Sheep”, with an equal intention of performing multiple positions within and through the text......., for 5 weeks, turning the two into a hybrid relational assemblage, intra-acting and becoming with the heath habitat, the other by-passing human and non-human animals, the changing weather and their fluctuating biological needs. She wanted to explore the discursive and material effects of a site......-specific human-nonhuman animal intra-action, to challenge the gendered and anthropocentric reading of a particular historical subject and to explore the messy constituents of the very categories of women and animals. In general she is occupied with how to animate and perform the intra-active entanglement...

  19. Estimating twin concordance for bivariate competing risks twin data.

    Science.gov (United States)

    Scheike, Thomas H; Holst, Klaus K; Hjelmborg, Jacob B

    2014-03-30

    For twin time-to-event data, we consider different concordance probabilities, such as the casewise concordance that are routinely computed as a measure of the lifetime dependence/correlation for specific diseases. The concordance probability here is the probability that both twins have experienced the event of interest. Under the assumption that both twins are censored at the same time, we show how to estimate this probability in the presence of right censoring, and as a consequence, we can then estimate the casewise twin concordance. In addition, we can model the magnitude of within pair dependence over time, and covariates may be further influential on the marginal risk and dependence structure. We establish the estimators large sample properties and suggest various tests, for example, for inferring familial influence. The method is demonstrated and motivated by specific twin data on cancer events with the competing risk death. We thus aim to quantify the degree of dependence through the casewise concordance function and show a significant genetic component.

  20. Spina bifida occulta and monozygotic twins.

    Science.gov (United States)

    Spacca, Barbara; Buxton, Neil

    2008-10-01

    Central nervous system maldevelopment can have different presentations in twins. We report on a case of different presentations of spina bifida occulta in monozygotic twins. The first twin presented at birth with a lipomyelomeningocele; a tethered cord was diagnosed in the second twin at 2 years of age. Neural tube defects (NTDs) are a group of common congenital malformations of the brain and spine generated during neurulation. The genetic basis of this process is still not well known. Whenever an NTD is diagnosed in one of a pair of twins, the other twin should also be evaluated for NTDs.

  1. [Twin dystocia: about one case of compaction].

    Science.gov (United States)

    Desseauve, D; Voluménie, J-L

    2008-09-01

    We report a case of twin dystocia during the evacuation of full-term fetus both in cephalic presentation. A low-outlet forceps for second-phase arrest was performed for the first twin but the head remained stuck to maternal perineum, mimicking a shoulder dystocia. Digital examination found a twin compaction, that is the presence of the second twin's fetal head at the level of the first twin's chest. The discrepancy between fetal weights and the use of forceps could favor this rare complication. Various maneuvers were described previously attempted to solve the problem. Forcing back the second head may help to achieve delivery of the first twin.

  2. [The Chinese national twin cohort: an update].

    Science.gov (United States)

    Gao, W J; Li, L M

    2017-06-10

    The importance of large cohort studies in China has been increasingly emphasized. As special group in the population, twins provide excellent natural resources since they share the same birthday, maternal intrauterine environment and early family environment. Twin cohorts are unique for and benefit on controlling the confounding factors as age, gender (same-sex twins), genetic background (monozygotic twins) or early environment (being raised together) in the etiological studies on complex diseases. In this review, we briefly introduce the objectives, current situation, challenges and opportunities related to the Chinese national twin cohort, focusing on the characteristics of twins that are different from other groups in the general population.

  3. TWIN GESTATION : A CHALLENGING TASK

    Directory of Open Access Journals (Sweden)

    Vrunda V.

    2015-03-01

    Full Text Available INTRODUCTION In the era of modern obstetrics when multiple pregnancies are on increase it is very important to know the incidence and obstetric outcomes of twin deliveries. Twin pregnancy is still associated with increased maternal and perinatal morbidity and mortality as well as healthcare costs . ( 1 , 2 , 3 MATERIALS AND METHODS : This is a r etrospective study of twin deliveries done in the rural medical college teaching hospital over a period of 3 years. RESULTS : During the study period , incidence of twin delivery was 19.37 per 1000 deliveries. Majority cases of twins were young primies in ag e group (20 - 30 years . Preterm delivery occurred in 68% cases and was therefore , the most common morbidity followed by anaemia (38% and PIH (28%. Most common presentation was vertex (66% and malpresentation were present in 44% of cases. 54% were deliver ed by caesarean section. In 88% second baby delivered within 15 minutes. Uterine inertia , PROM , fetal distress , PPH , cord prolapse and abruption were complications during labour. There was no maternal mortality in present study. Average weight of first baby was 1679.63 gms and 2 nd baby was 1586.94 gms. Perinatal mortality of 1 st baby was 27.55 for 1 st baby and 37.25% for 2 nd baby . Average gestational age for patients in whom cervical encirclage was done was 34 weeks. CONCLUSION: P reterm delivery and low birth weight babies are main challenges to the obstetrician. Incidence of LSCS is quite high with malpresentation of leading (twin A baby is a major indication for LSCS . The use of antenatal care services and good intrapartum mana gement will help improve outcome in twin pregnancies.

  4. Sheep-related Culture of Guizhou

    Institute of Scientific and Technical Information of China (English)

    WuZhengguang

    2003-01-01

    Sheep and goats, major livestock in Guizhou Steppe of southwest China, are of both practical and social value for local dwellers. As sheep is pronounced similar as "auspicious" in Chinese, its image is widely applied to every aspect of local society, including religious rites, calendar calculation, arts creation and architecture. Thus a sheep-related culture has been developed and prospered.

  5. Muscle free amino acid profiles are related to differences in skeletal muscle growth between single and twin ovine fetuses near term.

    Science.gov (United States)

    Sales, Francisco; Pacheco, David; Blair, Hugh; Kenyon, Paul; McCoard, Sue

    2013-01-01

    Twin sheep fetuses have reduced skeletal muscle weight near birth relative to singles as a result of restricted muscle hypertrophy. Intracellular free amino acids (FAA) are reported to regulate metabolic pathways which control muscle protein accretion, whereby reduced intracellular content of specific FAA may reduce their activation and therefore, muscle hypertrophy. The aim of this study was to determine whether differences in muscle weight between singleton and twin fetuses, under different maternal conditions is associated with reduced concentration of specific FAA. The FAA content in the semitendinosus muscle (ST) in singleton and twin fetuses (rank) at 140 days of gestation from heavy (H) or light (L) ewes fed ad libitum (A) or maintenance (M) level of nutrition was measured. Muscle weight was reduced in twin fetuses compared to singletons in all groups. Reduced concentrations of leucine, threonine and valine, but higher concentrations of methionine, ornithine, lysine and serine were found in twin fetuses compared to singletons. Maternal size and nutrition interaction with rank resulted in reduced glutamine in twins from HM-ewes (H-ewes under M nutrition) compared to their singleton counterparts. Maternal weight interaction with pregnancy rank reduced the concentration of arginine in twins, with a larger effect on H-ewes compared with L-ewes. Maternal size interaction with pregnancy rank resulted in twins from M-ewes to have lower alanine, while twins from A-ewes had lower aspartic acid concentration compared to singletons. The ST muscle weight was positively correlated only with arginine concentration after taking into account rank, size and nutrition. The present results indicate that reduced concentrations of specific intracellular FAA, such as arginine, leucine, valine, glutamine, which are known to play a role in muscle growth, could be acting as limiting factors for muscle hypertrophy in twin fetuses during late gestation. Ewe size and nutrition can

  6. Looking at Dauphiné twins in vein quartz as a potential paleostress indicator

    Science.gov (United States)

    Sintubin, Manuel; Wenk, Hans-Rudolf

    2013-04-01

    Paleostress studies commonly call upon (1) a fault slip data inversion technique, (2) a calcite twin stress inversion technique, (3) recrystallized grain size piezometry for quartz, or (4) direct measurements of residual lattice strain. Recent advances in orientation imaging microscopy (OIM) using electron backscatter diffraction (EBSD) on a scanning electron microscope (SEM) have revealed that Dauphiné twinning is very common in quartz in naturally deformed quartz-bearing rocks in a wide range of tectonometamorphic conditions. It has long been known that mechanical Dauphiné twinning in quartz can be stress-induced. Based on the results of an extensive EBSD-OIM analysis on vein quartz, taken from well-studied early to late-orogenic veins in the High-Ardenne slate belt (Germany, Belgium), we explore the potential use of mechanical Dauphiné twins as a paleostress indicator, possibly completing our toolbox for reconstructing paleostresses in the Earth's crust. The vein quartz studied precipitated in low-grade tectonometamorphic conditions (~200-400°C), typical for the brittle-plastic transition zone at the base of the seismogenic crust (~7-15km). Quartz has only been weakly affected by low to moderate temperature (200 to 400°C) crystal-plastic deformation. The samples show grains with a high concentration of Dauphiné twin boundaries and others free of twin boundaries, thus being untwinned or completely twinned. This pattern depends on the crystallographic orientation. Twin boundaries are arrested by grain or subgrain boundaries, suggesting that Dauphiné twinning occurred on a pre-existing fabric that resulted from crystal-plastic deformation. An analysis of the orientation distribution of the rhombs in the twinned variant domains of individual quartz (sub-)grains reveals a particular preferred orientation of the poles to rhombs. We will discuss the possible significance of these observations with respect to paleostresses that may have caused the mechanical

  7. Rare twin linked to high-pressure phase transition in iron

    Energy Technology Data Exchange (ETDEWEB)

    Dougherty, L.M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)], E-mail: lmdough@lanl.gov; Gray, G.T.; Cerreta, E.K.; McCabe, R.J.; Field, R.D.; Bingert, J.F. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2009-05-15

    At approximately 13 GPa, body-centered cubic alpha-iron undergoes a fully reversible, pressure-induced phase transition into hexagonal close-packed epsilon-iron. Microstructural evidence of this phase transition has been identified in the fully reverted alpha-iron as a large number of {l_brace}3 3 2{r_brace}<113> twins found primarily as secondary twins within {l_brace}1 1 2{r_brace}<111> primary twins. The {l_brace}3 3 2{r_brace}<113> twins were produced during high-pressure shock-loading of 1018 steel at a peak pressure above the alpha-epsilon phase transition pressure. The twins were identified using electron backscattered diffraction and transmission electron microscopy.

  8. Simulation of tantalum nanocrystals under shock-wave loading: Dislocations and twinning

    Science.gov (United States)

    Tramontina, D. R.; Hahn, E. N.; Meyers, M. A.; Bringa, E. M.

    2017-01-01

    We simulate strong shock waves in nanocrystalline tantalum using atomistic molecular dynamics simulations, for particle velocities in the range 0.35-2.0 km s-1, which induce pressures in the range 20-195 GPa. Our simulations explore strain rates in the range 108 s-1 - 1010 s-1, and lead to a peak strength in the range 3-15 GPa. Nanocrystalline tantalum exposed to strong shock waves demonstrates deformation enabled by concomitant dislocations, twinning, and grain boundary activity at a variety of particle velocities. Twinning is observed for a mean grain size of 7 nm, starting at around 32 GPa, in disagreement with models which predict a Hall-Petch behavior for twinning, i.e. a twinning stress scaling with grain size d as d-0.5, and supporting the presence of an inverse Hall-Petch effect for twinning at small grain sizes.

  9. Twin-twin transfusion syndrome: neurodevelopmental screening test

    Directory of Open Access Journals (Sweden)

    Amabile Vessoni Arias

    2015-03-01

    Full Text Available Objective To assess the neurodevelopmental functions (cognition, language and motor function of survivors of twin-twin transfusion syndrome (TTTS. Method Observational cross-sectional study of a total of 67 monochorionic diamniotic twins who underwent fetoscopic laser coagulation (FLC for treatment of TTTS. The study was conducted at the Center for Investigation in Pediatrics (CIPED, Universidade Estadual de Campinas. Ages ranged from one month and four days to two years four months. Bayley Scales of Infant and Toddler Development Screening Test-III, were used for evaluation. Results Most children reached the competent category and were classified as having appropriate performance. The preterm children scored worse than term infants for gross motor subtest (p = 0.036. Conclusion The majority of children reached the expected development according to their age. Despite the good neurodevelopment, children classified at risk should be monitored for development throughout childhood.

  10. TWIN PREGNANCY WITH ACARDIUS ANCEPS

    Directory of Open Access Journals (Sweden)

    Padma

    2014-02-01

    Full Text Available Acardiac twin is an anomaly unique to monochorionic multiple pregnancies, characterized by formation of malformed fetus with an absent or rudimentary (nonfunctional heart. Acardiac twinning, often results from abnormal placental vascular anastomoses. A 20 year old primigravida admitted to the department of Obstetrics and Gynecology S .S. Medical College, Rewa, on 26th July 2012 at the gestation of 34 week with spontaneous monochorionic monoamniotic twin pregnancy and fetal acardius with oligohydramnios. Patient was taking her treatment from private Hospital; acardius was diagnosed at 27 week due to late booking. In view of oligohydramnios and hypoxic changes in color Doppler, elective LSCS was done on 28/7/13 at 34 week 2 day, after betnesol coverage. She delivered a live, healthy, female child with good APGAR score having apparently no congenital anomaly, with a birth weight of 2.3 kg .The other twin was fetus acardius, of about900 gm. with head and face partially developed . Upper limb was rudimentary and lower limb was partially developed and malformed. External genitalia were developed as female. Placenta was monochorionic and monoamniotic, weighing500 gm. The umbilical cord of the normal twin was20 cm with central attachment, while the other umbilical cord was10 cm long with peripheral attachment

  11. TwinMux Testing System

    CERN Document Server

    Wong, Wei Wen; CERN. Geneva. PH Department

    2015-01-01

    During the CERN summer school program, I joined the CMS Muon Drift Tube (DT) group, and mainly worked on two projects, which, both of them, are related to the electronics of a new data concentrator called the “TwinMux”. My first task within the TwinMux project was to build an integrated software test station in order to run several tests on the functionality of the TwinMux hardware. Essentially, I had to integrate existing testing scripts, adding several new ones, into a single user-friendly testing platform which can perform quick, convenient and automated hardware testing. Later, I was also involved in the design of the local technical triggering of the DT. Such system relies on some firmware functionality built in the TwinMux and controlled by software. I had attempted two different approaches to design the communication topology of all the 12 TwinMux cards in order to send a user-defined logical operation to the read-out electronics. The final goal of this system is to drive local trigger signal for...

  12. Trim induced drag analysis and optimization of elastic twin-tailboom aircraft%双尾撑布局弹性飞机配平诱导阻力分析与优化

    Institute of Scientific and Technical Information of China (English)

    王立波; 杨超; 吴志刚

    2012-01-01

    Based on the energy method,the trim equations of flexible aircraft considering static aeroelasticity are derived.The idea of using static vortex lattice method combined with Trefftz plane theory and empirical formula to solve the induced drag and trim drag of flexible aircraft in trimmed level flight was proposed.The method of reducing total induced drag through optimization of the wing geometric twist angle was introduced.An UAV with twin tailbooms was analyzed.The result shows that the longitudinal bending stiffness has large effects on the total induced drag of the aircraft in such configuration,and it also affects the profile drag of the elevator deflexion and the total drag of the aircraft remarkably.Results of the optimization indicate that appropriate optimization of the geometric twist can make the whole span-wise lift distribution more close to the ellipse one,which will reduce the total induced drag effectively and other drag components positively.%基于能量方法推导了弹性飞机静气弹配平方程,提出了用定常涡格法结合Trefftz平面理论与阻力计算经验公式来求解弹性飞机定直平飞配平状态诱导阻力与配平阻力的分析思路,建立了通过机翼几何扭转角优化配置减小全机诱导阻力的分析方法.以某双尾撑无人机为例进行研究,分析发现尾撑纵向弯曲刚度对该布局飞机的全机诱导阻力、升降舵配平舵偏型阻及全机阻力等参数有重要影响.优化分析结果表明:通过机翼扭转角的合理优化,可使全机展向升力分布形式更接近于椭圆分布,进而有效减小全机诱导阻力,且对其他阻力分量也有一定的减缓效果.

  13. Complications arising in twin pregnancy: findings of prenatal ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Ah; Cho, Jeong Yeon; Lee, Young Ho; Song, Mi Jin; Min, Jee Yeon; Lee, Hak Jong; Han, Byoung Hee; Lee, Kyung Sang; Cho, Byung Jae; Chun, Yi Kyeong [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2003-03-01

    Multifetal gestations are high-risk pregnancies involving higher perinatal morbidity and mortality, and are subject to unique complications including twin oligohydramnios- polyhydramnios sequence, twin-to-twin transfusion syndrome, acardiac twins, conjoined twins, co-twin demise, and heterotopic pregnancies. The purpose of this study is to describe the prenatal ultrasonographic and pathologic findings of these complications.

  14. The animal model of talar osteonecrosis induced by intraosseous injection of pure ethanol in sheep%无水乙醇注射法建立羊距骨坏死模型的实验研究

    Institute of Scientific and Technical Information of China (English)

    张志; 郭征; 袁超凡; 李小康; 张涌泉; 王财儒

    2013-01-01

    目的 探讨无水乙醇注射法建立羊距骨坏死(ONT)的有效性. 方法 雌性小尾寒羊16只,左侧距骨采取骨内注射无水乙醇法诱导羊ONT,右侧距骨注射等量生理盐水作为空白对照组.2、4、12、24周(n=4)取材后通过大体标本、影像学和组织学检测,评价羊ONT的程度. 结果 对照组各时间点大体观察和组织学检测无骨坏死表现,影像学观察见钻洞修复.实验组2周时,距骨头内部骨质开始变性;4周时骨内出现空腔,X线片见明显低密度影,组织学见小梁骨内出现大量空骨陷窝;12周时距骨表面出明显软骨缺损与变性,X线片见低密度影加深扩大,组织学显示骨修复与纤维增生并存;24周时距骨整体严重破坏,X线片出现骨关节炎改变,组织学示大量纤维组织增生、占据原骨小梁生长部位. 结论 距骨头骨内无水乙醇注射法可以成功诱导羊ONT,该动物模型操作简单、成功率高、容易复制,为ONT干预研究创造了模型基础条件.%Objective To investigate the feasibility of creating a sheep model of talar osteonecrosis induced by intraosseous injection of absolute alcohol.Methods Sixteen female Small Tailed Han Sheep were randomized into 4 equal groups.In all animals the left tali were used to create the model of talar osteonecrosis while the right tali used as control by injection of physiological saline.Each group was sacrificed to harvest talar samples 2,4,12,24 weeks postoperatively.Talar osteonecrosis was evaluated by gross observation,imaging and histological examinations.Results The control tali did not show any signs of talar osteonecrosis at all time points and imaging examinations showed repair of the drilling holes after 4 weeks.In the experimental tali,the trabecular degeneration appeared at 2 weeks,and cavities formed inside the talar heads by the end of 4 weeks when the X-ray showed obvious low density in the area of talar head and a great deal of empty lacunas

  15. Prenatal undernutrition and postnatal overnutrition alter thyroid hormone axis function in sheep

    DEFF Research Database (Denmark)

    Johnsen, Lærke; Kongsted, Anna Hauntoft; Nielsen, Mette Olaf

    2013-01-01

    -bearing sheep were fed one of two diets during late gestation: NORM (fulfilling energy and protein requirements) or LOW (50% of NORM). From day-3 to 6-months after birth (around puberty) the twin lambs were assigned to each their diet: conventional (CONV) or high-carbohydrate-high-fat (HCHF), where after half...... the lambs were slaughtered. Remaining sheep (exclusively females) were fed the same moderate diet until 2-years of age (young adults). At 6-months and 2-years of age fasting challenges were conducted and target tissues were collected at autopsy. LG-UN caused adult hyperthyroidism associated with increased...... tissues. EL-ON increased TH levels in adolescent lambs, but this was reversed after diet correction, and not evident in adulthood. We conclude that LG-UN programmed TH-axis function at the secretory level and differentially in target tissues, which was increasingly manifested with age. Differential TH...

  16. Pre- and early-postnatal nutrition modify gene and protein expressions of muscle energy metabolism markers and phospholipid fatty acid composition in a muscle type specific manner in sheep

    DEFF Research Database (Denmark)

    Hou, Lei; Kongsted, Alice; Ghoreishi, S. M.

    2013-01-01

    determinants of insulin signalling in two types of skeletal muscles (longissimus dorsi (LD) and biceps femoris (BF)) and in the cardiac muscle (ventriculus sinister cordis (VSC)) of sheep from the same experiment. Twin-bearing ewes were fed either 100% (NORM) or 50% (LOW) of their energy and protein...

  17. The fracture behavior of twinned Cu nanowires: A molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jiapeng, E-mail: sun.jiap@gmail.com [College of Mechanics and Materials, Hohai University, Nanjing 210098 (China); Fang, Liang [State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, Shaanxi Province (China); Ma, Aibin, E-mail: aibin-ma@hhu.edu.cn [College of Mechanics and Materials, Hohai University, Nanjing 210098 (China); Jiang, Jinghua [College of Mechanics and Materials, Hohai University, Nanjing 210098 (China); Han, Ying [Key Laboratory of Advanced Structural Materials, Ministry of Education, Changchun University of Technology, Changchun 130012, Jilin Province (China); Chen, Huawei [Department of Applied Physics, School of Science, Xi’an Jiaotong University, Xi’an 710049, Shaanxi Province (China); Han, Jing [School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu Province (China)

    2015-05-14

    The molecular dynamics simulations are performed to explore the fracture behavior and the ductility of the twinned Cu nanowires containing orthogonally oriented growth CTBs due to the uniaxial tensile deformation. The results reveal that, the fracture behavior and the ductility of the twinned nanowires are not related to the length of the nanowires but also intensively related to the twin boundary spacing. When the twin boundary space is changed, the twinned nanowires undergo three distinct failure modes which include ductile fracture, brittle fracture and ductile-to-brittle transition depending on the length of the nanowires. We also find a reduction in the ductility of the twinned nanowires, which is ascribed to the deformation localization induced by the Lomer dislocation and the rapid necking resulted from the twinning partial slipping. Finally, the atomic-level process that occurs during deformation until final fracture are examined in detail, and a new formation mechanism of the Lomer dislocation is observed when a 90° partial dislocation transmits across a coherent twin boundary.

  18. Breast-Feeding Twins: Making Feedings Manageable

    Science.gov (United States)

    ... more than one baby? Here's help breast-feeding twins or other multiples, from getting positioned and ensuring ... babies who are born prematurely, as are many twins and higher order multiples. Breast milk is easier ...

  19. Risk of Oral Clefts in Twins

    DEFF Research Database (Denmark)

    Grosen, Dorthe; Bille, Camilla; Petersen, Inge

    2011-01-01

    BACKGROUND:: Small studies have indicated that twinning increases the risk of oral cleft. METHODS:: We used data from a Danish national population-based cohort study to investigate whether twinning was associated with isolated oral cleft, and to estimate the twin probandwise concordance rate...... and heritability. Twins (207 affected/130,710) and singletons (7766 affected/4,798,526) born from 1936 through 2004 in Denmark were ascertained by linkage among the Danish Facial Cleft Database, the Danish Twin Registry, and the Civil Registration System. We computed oral cleft prevalence and prevalence proportion...... ratio for twins versus singletons, stratified for 3 subphenotypes. Probandwise concordance rates and heritability for twins were estimated for 2 phenotypes-cleft lip with or without cleft palate (CL/P) and cleft palate (CP). RESULTS:: The prevalence of oral cleft was 15.8 per 10,000 twins and 16.6 per...

  20. Having Twins? How to Stay Healthy

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Having Twins? How to Stay Healthy Page Content Article Body ... the eyes of obstetricians. Many would call a twin pregnancy a high-risk pregnancy , but don’t ...

  1. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)

  2. Preterm twin gestation and cystic periventricular leucomalacia

    NARCIS (Netherlands)

    Resch, B; Jammernegg, A; Vollaard, E; Maurer, U; Mueller, WD; Pertl, B

    2004-01-01

    Objective: To identify risk factors for the development of cystic periventricular leucomalacia (PVL) in twin gestation. Design: Retrospective case-control study. Setting: Tertiary care university hospital, Department of Paediatrics, Division of Neonatology, Graz, Austria. Patients: Preterm twin gest

  3. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)

  4. Milk yield of some Croatian sheep breeds

    OpenAIRE

    Kristijan Pandek; Boro Mioč; Zdravko Barać; Vesna Pavić; Neven Antunac; Zvonimir Prpić

    2005-01-01

    Among the most important breeds of sheep, used for the milk production in Croatia, are the sheep from Pag, Brač, Cres, Istrian and Travnik΄s sheep, different crossbreeds and, recently, East Friesian sheep. The aim of the research was to determine the genotype effect on lactation period, milk yield and protein and fat content, which are important in cheese making. The longest lactation period (213 days) had East Friesian sheep, while the highest total milk production (294 kg) and the highest p...

  5. Twins or two single children

    Directory of Open Access Journals (Sweden)

    2002-08-01

    Full Text Available Based on Swedish register data, we compared the influence of a twin birth on the divorce risk with the influence of the sequential birth of two single children. The divorce risk for a woman with a very young child was lower than the risk for women without children or women with children older than 3.5 years. This behaviour was essentially independent of the number of children and whether or not the woman gave birth to twins. The effect of parity was much smaller than the effect of child age. The influence of twins on the divorce risk appeared to fall between that of a first and a second singleton.

  6. Twin TQFTs and Frobenius Algebras

    Directory of Open Access Journals (Sweden)

    Carmen Caprau

    2013-01-01

    Full Text Available We introduce the category of singular 2-dimensional cobordisms and show that it admits a completely algebraic description as the free symmetric monoidal category on a twin Frobenius algebra, by providing a description of this category in terms of generators and relations. A twin Frobenius algebra (C,W,z,z∗ consists of a commutative Frobenius algebra C, a symmetric Frobenius algebra W, and an algebra homomorphism z:C→W with dual z∗:W→C, satisfying some extra conditions. We also introduce a generalized 2-dimensional Topological Quantum Field Theory defined on singular 2-dimensional cobordisms and show that it is equivalent to a twin Frobenius algebra in a symmetric monoidal category.

  7. Twins' injuries: genetic and environmental risks / twin research reports / human interest stories.

    Science.gov (United States)

    Segal, Nancy L

    2011-04-01

    The relative contributions of genetic and environmental factors to unintentional injuries are of interest to families with young twins. A recent study found that childhood injuries are explained mostly by child-specific environmental factors. Next, twin research reviews of the association between periodontal disease and cancer, secular trends in gestational age and birthweight, and language development in hearing and deaf co-twins are also summarized. Interesting reports of newborn twins, twin-like relationships, twin interactions and missed twin relationships are presented.

  8. The Fourth International Network of Twin Registries: Overview from Osaka/Research Reviews: Familial Fraternal Twinning; Twin Study of Masculine Faces; Physical Aggression and Epigenetics; Prenatal Education for Parents of Twins/Current Events: 2016 Guinness Book of World Records; Oldest Living Male Twins; Twins Reunited at Sixty-Nine; Panda Twins; Twins.com.

    Science.gov (United States)

    Segal, Nancy L

    2015-12-01

    The 4th International Network of Twin Registries (INTR) Consortium Meeting took place in Osaka, Japan, September 28-29, 2015. The venue was the Osaka Medical Center for Medical Innovation and Translational Research. An overview of presentations and other activities is provided. Next, 1930s research on familial fraternal twinning, preference for masculine faces, physical aggression and epigenetics, and a prenatal education program for parents of multiples are described. Current twin-related events include the 2016 Guinness Book of World Records (GWR), the oldest living male twins, newly reunited twins, the birth of panda twins and a controversial twin-based website.

  9. Do Twin Boundaries Always Strengthen Metal Nanowires?

    OpenAIRE

    Zhang Yongfeng; Huang Hanchen

    2008-01-01

    Abstract It has been widely reported that twin boundaries strengthen nanowires regardless of their morphology—that is, the strength of nanowires goes up as twin spacing goes down. This article shows that twin boundaries do not always strengthen nanowires. Using classical molecular dynamics simulations, the authors show that whether twin boundaries strengthen nanowires depends on the necessary stress for dislocation nucleation, which in turn depends on surface morphologies. When nanowire...

  10. Twins reunited: scientific and personal perspectives/twin research studies: multiple birth effects on IQ and body size; life style, muscles, and metabolism; monochorionic dizygotic twin with blood chimerism; amniocentesis for twins/twins in the media: identical doctors; freedom fighter for twins; twin scholarships; Auguste and Jean-Felix Piccard; twins born apart.

    Science.gov (United States)

    Segal, Nancy L; Mulligan, Christy A

    2014-04-01

    A reunion of 38-year-old female monozygotic twins took place in Daegu, South Korea, on January 14, 2014. Scientific and personal perspectives on this extraordinary event are provided. A review of timely twin research follows, covering the effects of multiple births on IQ and body size, lifestyle and physical fitness associations, a rare case of a dizygotic twin with blood chimerism and definitional issues surrounding amniocentesis-related loss in multiple birth pregnancies. Interesting and informative mention of twins in the media includes twin doctors, a twin freedom fighter, the availability of college scholarships for twins, a new book about the Piccard family (two of whose members were twins), and co-twins born before and after the new year. A follow-up to a previous mention of identical twin biatheletes is also provided.

  11. Histopathological Analysis of Liver During Pregnancy Toxemia in Small-tailed Han Sheep

    Institute of Scientific and Technical Information of China (English)

    Mingcheng WANG; Enzhong LI; Gailing WANG

    2014-01-01

    The present work aimed to investigate the microscopic and ultramicro-scopic structure of the liver to assess the level of hepatic impairment during preg-nancy toxemia. Seven pregnant smal-tailed Han sheep of negative urine ketone bodies were assessed in this study. Toxemia was induced by limiting food and movement late in pregnancy. Three sheep developed obvious clinical symptoms with motor weakness, depression, anorexia, locomotion disturbances, blindness and lan-guishment. We harvested their liver tissues as pathological material, and used rou-tine histological and electronic microscopy methods to observe the histopathological changes in smal-tailed Han sheep induced by pregnancy toxemia. Autopsy of the livers of the sheep revealed deep yel ow coloration, intumescence and hemorrhage on the surface. Microstructural features indicated fatty degeneration, which is a main characteristic of fatty liver. Hepatocel ular ultrastructural changes were observed un-der an electronic microscope. The characteristic findings were nucleolus concentra-tion, vacuolation of mitochondria and excessive glycogen granules in the cytoplasm. Via this experimental protocol, pregnancy toxemia of sheep was successful y in-duced, providing a pathological model for the study of this disease. After the experi-mental induction of pregnancy toxemia, the clinical symptoms of pathogenic sheep and pathological changes to their livers exhibited obvious characteristics of pregnan-cy toxemia.

  12. Fatal pneumonia following inoculation of healthy bighorn sheep with Pasteurella haemolytica from healthy domestic sheep.

    Science.gov (United States)

    Foreyt, W J; Snipes, K P; Kasten, R W

    1994-04-01

    In a series of three experiments, isolates of Pasteurella haemolytica biotype A, serotype 2, ribotype reference WSU-1, from healthy domestic sheep, were inoculated intratracheally into eight bighorn sheep (Ovis canadensis canadensis) and seven domestic sheep with doses of bacteria ranging from 5.3 x 10(8) to 8.6 x 10(11) colony forming units. Seven of eight inoculated bighorn sheep died from acute pneumonia within 48 hr of inoculation, whereas all seven domestic sheep inoculated with comparable or greater doses of bacteria remained healthy. One contact control bighorn sheep also died 6 days after its penmates received P. haemolytica. Three other noncontact control bighorn sheep remained healthy during the experiments. Pasteurella haemolytica biotype A, serotype 2, ribotype reference WSU-1 in the inocula was recovered from one or more tissues from all bighorns that died; whereas, it was not detected in any bighorn sheep before inoculation. Three different ribotypes of P. haemolytica A2 were recovered from bighorn sheep; however, only the ribotype reference WSU-1 in the domestic sheep-origin inoculum was recovered from all dead bighorn sheep, and was not recovered from bighorn sheep that survived the experiments. Thus, a relatively nonpathogenic and common isolate of P. haemolytica from healthy domestic sheep was lethal in bighorn sheep under experimental conditions.

  13. Multiple rectal carcinoid tumors in monozygotic twins.

    Science.gov (United States)

    Doi, Momoko; Ikawa, Osamu; Taniguchi, Hiroki; Kawamura, Takuji; Katsura, Kanade

    2016-08-01

    We report multiple rectal carcinoid tumors in monozygotic twins who, respectively, had 42 and 36 carcinoid tumors in the lower rectum. This is the first report about carcinoid tumors in monozygotic twins. Both twins developed a similar number of rectal carcinoids with a similar distribution. Investigation of their genetic background may provide information about the origin of these tumors.

  14. Postpartum Mental State of Mothers of Twins

    Science.gov (United States)

    Brantmüller, Éva; Gyúró, Mónika; Galgán, Kitti; Pakai, Annamária

    2016-01-01

    Twin birth is a relevant risk factor for postnatal depression (PND). The primary objective of our study is to reveal the prevalence of suspected cases of depression and to identify some background factors among mothers of twins. We applied convenience sampling method within a retrospective, quantitative study among mothers given birth to twins for…

  15. A RARE CASE OF ACARDIAC TWIN

    OpenAIRE

    Padmaja; Nirmala,

    2015-01-01

    Fetus Acardiacus is a very rare manifestation of twin gestation . This happens due to TRAP sequence . That is Twin reversed arterial perfusion . In this case an amorphous mass was seen on a routine antenatal scan and followed as there was a live twin also . The case report highlights the importance of careful scanning and ...

  16. MIR phasing using merohedrally twinned crystals

    NARCIS (Netherlands)

    Terwisscha van Scheltinga, Anke C.; Valegård, Karin; Hajdu, Janos; Andersson, Inger

    2003-01-01

    Merohedral twinning is a crystal-growth disorder that seriously hinders the determination of macromolecular crystal structures by isomorphous replacement. The strategies used in the structures solved so far are discussed. Several methods can be used to determine the extent of twinning, the twin frac

  17. Epigenetic Epidemiology of Complex Diseases Using Twins

    DEFF Research Database (Denmark)

    Tan, Qihua

    2013-01-01

    through multiple epigenetic mechanisms. This paper reviews the new developments in using twins to study disease-related epigenetic alterations, links them to lifetime environmental exposure with a focus on the discordant twin design and proposes novel data-analytical approaches with the aim of promoting...... a more efficient use of twins in epigenetic studies of complex human diseases....

  18. [The diagnostic algorithm in twin pregnancy].

    Science.gov (United States)

    Ropacka-Lesiak, Mariola; Szaflik, Krzysztof; Breborowicz, Grzegorz H

    2015-03-01

    This paper presents the diagnostic algorithm in twin pregnancy. The most important sonographic parameters in the assessment of twins have been discussed. Moreover, the most significant complications of twin pregnancy as well as diagnostic possibilities and management, have been also presented and defined.

  19. Natal Influences and Twin Differences: Draft.

    Science.gov (United States)

    Van den Daele, Leland D.

    1972-01-01

    A classification of natal influences is proposed with a model of their operation. Natal influences affect maternal capacity, maternal load, and maternal efficiency. Since maternal load is increased in twin pregnancy, results of twin studies must be generalized with caution. The method of co-twin control is exemplified by examination of a small…

  20. Twin and genetic effects on life events

    NARCIS (Netherlands)

    Middeldorp, C.M.; Cath, D.C.; Vink, J.M.; Boomsma, D.I.

    2005-01-01

    Twin studies that examine the effect of specific environmental risk factors on psychiatric disorders assume that there are no differences in prevalences of these risk factors between twins and singletons. Violation of this assumption signifies that the results from twin studies might not generalize

  1. Concordance for multiple sclerosis in Danish twins

    DEFF Research Database (Denmark)

    Hansen, T; Skytthe, Axel; Stenager, Egon

    2005-01-01

    The occurrence of multiple sclerosis (MS) in twins has not previously been studied in complete nationwide data sets. The existence of almost complete MS and twin registries in Denmark ensures that essentially unbiased samples of MS cases among twins can be obtained. In this population-based study...

  2. The Charles Perkins Centre's Twins Research Node.

    Science.gov (United States)

    Ferreira, Lucas C; Craig, Jeffrey M; Hopper, John L; Carrick, Susan E

    2016-08-01

    Twins can help researchers disentangle the roles of genes from those of the environment on human traits, health, and diseases. To realize this potential, the Australian Twin Registry (ATR), University of Melbourne, and the Charles Perkins Centre (CPC), University of Sydney, established a collaboration to form the Twins Research Node, a highly interconnected research facility dedicated specifically to research involving twins. This collaboration aims to foster the adoption of twin designs as important tools for research in a range of health-related domains. The CPC hosted their Twins Research Node's launch seminar entitled 'Double the power of your research with twin studies', in which experienced twin researchers described how twin studies are supporting scientific discoveries and careers. The launch also featured twin pairs who have actively participated in research through the ATR. Researchers at the CPC were surveyed before the event to gauge their level of understanding and interest in utilizing twin research. This article describes the new Twins Research Node, discusses the survey's main results and reports on the launch seminar.

  3. A case of conjoined twins (thoraco-omphalopygopagus tribrachius tetrapus) in lamb

    Science.gov (United States)

    Mazaheri, Yazdan; Nourinezhad, Jamal; Ranjbar, Reza; Khaksary Mahabady, Mahmood; Ghadiri, Ali Reza; Lombeshkon, Hamid

    2014-01-01

    Nearly completed conjoined or fused symmetrical twins are generally called diplopagus. Sheep conjoined twins have been reported less than cow. An apparently female conjoined twin lambs was examined based on external and internal features. In radiology, two vertebral columns and two pairs of the ribs were seen. Only two heads and two necks were separated (thoraco-omphalopygopagus). There were three forelimbs (tribrachius), one of which grew on dorsal region as a notomelus. Teat buds of the monsters differed in number. Only one lamb had umbilicus, including one umbilical vein, and two umbilical arteries locating besides one urinary bladder. This lamb had also one uterus. Two-separated alimentary tracts were observed in a common abdomen. Common thorax and abdominal cavities were separated by a diaphragm. There were two esophageal hiatuses, and two caval foramina but only one aortic hiatus. Two pairs of lungs and two unequal and connected hearts in a common pericardium were observed. Abnormality of the circulatory system might have caused the death of the twins. PMID:25568697

  4. Thoraco-omphalopagus conjoined twins in Chamois-coloured domestic goat kids.

    Science.gov (United States)

    Binanti, D; Riccaboni, P

    2012-06-01

    Conjoined twins have been observed in a wide range of mammalian and non-mammalian species; they are considered to be more common in bovine, less frequent in sheep and pig and extremely rare in horse and goat. A pair of female conjoined twins was delivered from a 2-year-old Chamois-coloured domestic goat. Post-mortem examination revealed two identical and symmetrical twins, fused from the manubrium sterni to the region just caudal to the umbilicus. The rib cages were conjoined in the ventral plane with a single set of pericardial, pleural and peritoneal cavities. Internal examination revealed the presence of a common diaphragm and a single enlarged liver. Within a single central pericardium, two malformed hearts were present. Reports on this type of congenital duplication in goats have not been found in the literature. Thoracopagus and thoraco-omphalopagus are the most common types of conjoined twins in human beings and are associated with the highest mortality because of the frequent incidence of complex cardiac anatomy.

  5. Development of a sheep challenge model for Rift Valley fever.

    Science.gov (United States)

    Faburay, Bonto; Gaudreault, Natasha N; Liu, Qinfang; Davis, A Sally; Shivanna, Vinay; Sunwoo, Sun Young; Lang, Yuekun; Morozov, Igor; Ruder, Mark; Drolet, Barbara; Scott McVey, D; Ma, Wenjun; Wilson, William; Richt, Juergen A

    2016-02-01

    Rift Valley fever (RVF) is a zoonotic disease that causes severe epizootics in ruminants, characterized by mass abortion and high mortality rates in younger animals. The development of a reliable challenge model is an important prerequisite for evaluation of existing and novel vaccines. A study aimed at comparing the pathogenesis of RVF virus infection in US sheep using two genetically different wild type strains of the virus (SA01-1322 and Kenya-128B-15) was performed. A group of sheep was inoculated with both strains and all infected sheep manifested early-onset viremia accompanied by a transient increase in temperatures. The Kenya-128B-15 strain manifested higher virulence compared to SA01-1322 by inducing more severe liver damage, and longer and higher viremia. Genome sequence analysis revealed sequence variations between the two isolates, which potentially could account for the observed phenotypic differences. We conclude that Kenya-128B-15 sheep infection represents a good and virulent challenge model for RVF.

  6. Twin-box ITER joints under electromagnetic transient loads

    Energy Technology Data Exchange (ETDEWEB)

    Stepanov, Boris, E-mail: boris.stepanov@psi.ch; Bruzzone, Pierluigi; March, Stephen; Sedlak, Kamil

    2015-10-15

    Highlights: • ITER “twin-box” joint design. • Dependence of the joint resistance on current. • Resistance change under the transient electromagnetic load. • Breakdown of the contributions to the joint resistance. • Field dump and conductor performance behind the twin-box joint. - Abstract: The ITER Toroidal Field (TF) coil winding packs are designed to be wound in double-pancakes. The twin-box joint provides the electrical pancake-to-pancake connection between the two Nb{sub 3}Sn 68 kA conductors and electrical coil-to-bus bar connection between the TF coil terminations and NbTi 68 kA bus bars conductors. The twin-box full size joint sample connecting two Nb{sub 3}Sn conductors (pancake-to-pancake joint) was prepared in order to qualify the TF joint assembly in SULTAN Test Facility. The original goal of the test program was the measurement of joint resistance at different operating conditions. The accidental dump of the SULTAN background field caused a noticeable increase of resistance due to the induced electromagnetic transient load. The TF joint test was continued in order to investigate a change of joint resistance following electromagnetic transient loading which was triggered by intentional dump of the background field. Also, a dependence of the joint resistance on current was observed; in order to explore the origin of resistance change, additional experiments were performed with a modified (artificially degraded) TF twin-box joint. The test results of a TF twin-box joint after electromagnetic transient loading and performance of the joint after a modification are presented in this paper. The performance of Nb{sub 3}Sn 68 kA conductor observed during those tests is highlighted as well.

  7. Pinning in twin boundaries of YBa sub 2 Cu sub 3 O sub 7-. delta. single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, W.K.; Welp, U.; Vandervoort, K.G.; Crabtree, G.W. (Argonne National Lab., IL (USA)); Liu, J.Z. (California Univ., Davis, CA (USA). Dept. of Physics); Brooks, J.; Hettinger, J.; Hannahs, S.T. (Boston Univ., MA (USA). Dept. of Physics); Fleshler, S. (Argonne National Lab., IL (USA) Purdue Univ., Lafayette, IN (USA))

    1990-01-01

    We present direct observation of Lorentz force induced flux motion and pinning by twin boundaries in single crystal YBa{sub 2}Cu{sub 3}O{sub 7 {minus}{delta}}. From AC magnetoresistance measurements, we derive the effective pinning potential attributed to twin boundaries. 7 refs., 3 figs.

  8. NOTE: Increasing cardiac output and decreasing oxygenation sequence in pump twins of acardiac twin pregnancies

    Science.gov (United States)

    van Gemert, Martin J. C.; Umur, Asli; van den Wijngaard, Jeroen P. H. M.; Van Bavel, Ed; Vandenbussche, Frank P. H. A.; Nikkels, Peter G. J.

    2005-02-01

    An acardiac twin pregnancy is a rare but serious complication of monochorionic twinning and consists of an acardiac twin and a pump twin. The acardiac twin is a severely malformed fetus that lacks most organs, particularly a heart, but grows during pregnancy because it is perfused by the developmentally normal pump twin via a set of arterioarterial and venovenous placental anastomoses. Pump twins die intrauterine or neonatally in about 50% of the cases. Because the effects of an acardiac mass on the pump twin's development are incompletely known, methods for outcome prognosis are currently not available. We sought to derive simple relations for the pump twin's excess cardiac output and decreased oxygenation and to use available clinical cases for a preliminary test of the model. As a method, we used a theoretical flow model to represent the fetoplacental circulation of an acardiac twin pregnancy and estimated blood deoxygenation and reoxygenation following perfusion of the two bodies and placentas, respectively. The results show the pump twin's excess cardiac output and decrease of venous oxygen saturation to depend on the ratio of pump twin to acardiac twin umbilical blood flow, whose ratio can be measured by ultrasonography. The clinical cases show a decreasing umbilical flow ratio with gestation. In conclusion, prospective serial study is necessary to test whether measurement of umbilical flow ratios allows monitoring the pump twin's pathophysiologic development, possibly resulting in a guideline for prognosis of pump twin survival.

  9. Increasing cardiac output and decreasing oxygenation sequence in pump twins of acardiac twin pregnancies

    Energy Technology Data Exchange (ETDEWEB)

    Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); VanBavel, Ed [Department of Medical Physics, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Vandenbussche, Frank P H A [Department of Obstetrics, Leiden University Medical Center, Leiden (Netherlands); Nikkels, Peter G J [Department of Pathology, University Medical Center, Utrecht (Netherlands)

    2005-02-07

    An acardiac twin pregnancy is a rare but serious complication of monochorionic twinning and consists of an acardiac twin and a pump twin. The acardiac twin is a severely malformed fetus that lacks most organs, particularly a heart, but grows during pregnancy because it is perfused by the developmentally normal pump twin via a set of arterioarterial and venovenous placental anastomoses. Pump twins die intrauterine or neonatally in about 50% of the cases. Because the effects of an acardiac mass on the pump twin's development are incompletely known, methods for outcome prognosis are currently not available. We sought to derive simple relations for the pump twin's excess cardiac output and decreased oxygenation and to use available clinical cases for a preliminary test of the model. As a method, we used a theoretical flow model to represent the fetoplacental circulation of an acardiac twin pregnancy and estimated blood deoxygenation and reoxygenation following perfusion of the two bodies and placentas, respectively. The results show the pump twin's excess cardiac output and decrease of venous oxygen saturation to depend on the ratio of pump twin to acardiac twin umbilical blood flow, whose ratio can be measured by ultrasonography. The clinical cases show a decreasing umbilical flow ratio with gestation. In conclusion, prospective serial study is necessary to test whether measurement of umbilical flow ratios allows monitoring the pump twin's pathophysiologic development, possibly resulting in a guideline for prognosis of pump twin survival. (note)

  10. Ivermectin pharmacokinetics in lactating sheep

    NARCIS (Netherlands)

    Cerkvenik, V.; Grabnar, V.; Skubic, V.; Doganoc, D.Z.; Beek, W.M.J.; Keukens, H.J.; Kosorok, M.D.; Pogacnik, M.

    2002-01-01

    Ivermectin (IVM) concentrations in plasma and milk were studied in six Istrian Pramenka dairy sheep after a single subcutaneous dose of 0.2 mg/kg b.w. of IVM in the early lactation period to describe IVM disposition in milk and to evaluate the transfer of IVM residues via milk to suckling lambs. Lar

  11. Ventral hernia in the sheep.

    Science.gov (United States)

    Tirgari, M

    1980-01-05

    Between November 1974 and November 1978, 11 sheep with ventral hernia were referred for surgical correction. The anatomy of the area, clinical findings, operative details, surgicopathological observations and postoperative results are described. A comparison of these cases with hernial correction in horses and cattle is made.

  12. Aspectos clínicos e características do leite em ovelhas com mastite induzida experimentalmente com Staphylococcus aureus Clinical aspects and characteristics of the milk in sheep with mastitis experimentally induced with Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Rogério A. Santos

    2007-01-01

    Full Text Available Este trabalho teve por objetivo estudar os aspectos clínicos e as características físico-químicas do leite em ovelhas com mastite induzida experimentalmente com Staphylococcus aureus. Foram utilizados dez animais da raça Santa Inês, com peso médio de 30 kg, fêmeas, primíparas recém-paridas, mantidos em apriscos e clinicamente sadios. Após se estabelecer os padrões de normalidade para as variáveis estudadas, os animais foram inoculados experimentalmente numa mama com uma cepa de S. aureus, empregando-se o inóculo de 1,0x10(4ufc/ml, enquanto a outra serviu como controle. As observações clínicas e laboratoriais foram realizadas nos intervalos de 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 168, 180, 288 e 336 horas após a inoculação do agente etiológico (PI. Todos os animais apresentaram manifestações clínicas sistêmicas e nas glândulas inoculadas, observadas com mais intensidade a partir de 24 horas após a inoculação. Alterações significativas (PThe objective was to study the clinical aspects and the physical-chemical characteristics of the milk in sheep with mastitis experimentally induced with Staphylococcus aureus. For such, were used 10 Santa Inês primiparity ewes, weighing 30 kg, clinically healthy and housed in a stall. After establishing the normality patterns for the studied variables, the animals were inoculated into one teat of the udder with an inoculum of 1.0x10(4ufc/ml of S. aureus, while the other gland served as control. The clinical observations were accomplished in intervals of 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 168, 180, 288 and 336 hours after the inoculation of the agent (PI. All the animals presented clinical systemic manifestations, and in the inoculated glands with more intensity from 24 hours on after the inoculation. There were significant alterations (P<0.05 in the production and physical-chemical composition of the milk in relation to the controls, with reduction of volume

  13. The 'Planemo' Twins

    Science.gov (United States)

    2006-08-01

    The cast of exoplanets has an extraordinary new member. Using ESO's telescopes, astronomers have discovered an approximately seven-Jupiter-mass companion to an object that is itself only twice as hefty. Both objects have masses similar to those of extra-solar giant planets, but they are not in orbit around a star - instead they appear to circle each other. The existence of such a double system puts strong constraints on formation theories of free-floating planetary mass objects. ESO PR Photo 29a/06 ESO PR Photo 29a/06 Double System of Planetary Mass Objects (Artist's View) Ray Jayawardhana of the University of Toronto (Canada) and Valentin D. Ivanov of ESO report the discovery in the August 3 issue of Science Express, the rapid online publication service of the journal Science. "This is a truly remarkable pair of twins - each having only about one percent the mass of our Sun," said Jayawardhana. "Its mere existence is a surprise, and its origin and fate a bit of a mystery." Roughly half of all Sun-like stars come in pairs. So do about a sixth of brown dwarfs, 'failed stars' that have less than 75 Jupiter masses and are unable to sustain nuclear fusion in their cores. During the past five years, astronomers have identified a few dozen of even smaller free-floating planetary mass objects, or planemos, in nearby star forming regions. Oph 162225-240515, or Oph1622 for short, is the first planemo found to be a double. The researchers discovered the companion candidate in an optical image taken with ESO's 3.5-m New Technology Telescope at La Silla, Chile. They decided to take optical spectra and infrared images of the pair with ESO's 8.2-m Very Large Telescope to make sure that it is a true companion, instead of a foreground or background star that happens to be in the same line of sight. These follow up observations indeed confirmed that both objects are young, at the same distance, and much too cool to be stars. This suggests the two are physically associated. ESO PR

  14. Validation of the Osteopenia Sheep Model for Orthopaedic Biomaterial Research

    DEFF Research Database (Denmark)

    Ding, Ming; Danielsen, C.C.; Cheng, L.

    2009-01-01

    Validation of the Osteopenia Sheep Model for Orthopaedic Biomaterial Research +1Ding, M; 2Danielsen, CC; 1Cheng, L; 3Bollen, P; 4Schwarz, P; 1Overgaard, S +1Dept of Orthopaedics O, Odense University Hospital, Denmark, 2Dept of Connective Tissue Biology, University of Aarhus, Denmark, 3Biomedicine...... Lab, University of Southern Denmark, 4Dept of Geriatrics, Glostrup University Hospital, Denmark ming.ding@ouh.regionsyddanmark.dk   Introduction:  Currently, majority orthopaedic prosthesis and biomaterial researches have been based on investigation in normal animals. In most clinical situations, most...... resemble osteoporosis in humans. This study aimed to validate glucocorticoid-induced osteopenia sheep model for orthopaedic implant and biomaterial research. We hypothesized that a 7-month GC treatment together with restricted diet but without OVX would induce osteopenia. Materials and Methods: Eighteen...

  15. Elastic interaction between twins during tensile deformation of austenitic stainless steel

    DEFF Research Database (Denmark)

    Juul, Nicolai Ytterdal; Winther, Grethe; Dale, Darren

    2016-01-01

    In austenite, the twin boundary normal is a common elastically stiff direction shared by the two twins, which may induce special interactions. By means of three-dimensional X-ray diffraction this elastic interaction has been analysed and compared to grains separated by conventional grain boundaries....... However, the components of the Type II stress normal to the twin boundary plane exhibit the same large variations as for the grain boundaries. Elastic grain interactions are therefore complex and must involve the entire set of neighbouring grains. The elastic-regime stress along the tensile direction...

  16. Epigenetic Epidemiology of Complex Diseases Using Twins

    DEFF Research Database (Denmark)

    Tan, Qihua

    2013-01-01

    In the past decades, studies on twins have had a great impact on dissecting the genetic and environmental contributions to human diseases and complex traits. In the era of functional genomics, the valuable samples of twins help to bridge the gap between gene activity and environmental conditions...... through multiple epigenetic mechanisms. This paper reviews the new developments in using twins to study disease-related epigenetic alterations, links them to lifetime environmental exposure with a focus on the discordant twin design and proposes novel data-analytical approaches with the aim of promoting...... a more efficient use of twins in epigenetic studies of complex human diseases....

  17. The Danish political twin study

    DEFF Research Database (Denmark)

    Klemmensen, Robert; Hobolt, Sara B; Dinesen, Peter Thisted

    2012-01-01

    We compare a recent Danish twin survey on political attitudes and behaviors to a nationally representative survey covering similar topics. We find very similar means and variances for most of our constructed scales of political attitudes and behaviors in the two surveys, although even small...

  18. Twin-Arginine Protein Translocation

    NARCIS (Netherlands)

    Goosens, Vivianne J; van Dijl, Jan Maarten

    2016-01-01

    Twin-arginine protein translocation systems (Tat) translocate fully folded and co-factor-containing proteins across biological membranes. In this review, we focus on the Tat pathway of Gram-positive bacteria. The minimal Tat pathway is composed of two components, namely a TatA and TatC pair, which a

  19. Chlamydiaceae and chlamydial infections in sheep or goats.

    Science.gov (United States)

    Rodolakis, A; Laroucau, K

    2015-12-14

    Chlamydiae induce a range of pathological syndromes in small ruminants. Abortion is the most common clinical expression of the infection that causes important economic losses and presents a risk to human health, particularly in pregnant women. The present paper gives an overview of chlamydial infections in sheep and goats, focusing specifically on abortion and on recent data brought by cellular and genomic approaches regarding genotyping, virulence of strains, epidemiology, diagnosis, pathogenesis and control of the disease.

  20. Improving the Local Sheep in Gansu via Crossing with Introduced Sheep Breeds Dorset and Borderdale

    Institute of Scientific and Technical Information of China (English)

    Sun; Xiaoping; Liu; Jianbin; Zhang; Wanlong; Lang; Xia; Yang; Bohui; Guo; Jian; Feng; Ruilin

    2014-01-01

    In order to improve the meat performance of local sheep in Gansu Province,Dorset and Borderdale were introduced to crossbreed with local sheep which were Tan sheep,Small-tail Han sheep and Mongolia sheep. The offspring under different crossbreeding combinations were sampled randomly at the different growing stage to measure their growth traits so as to select optimize the crossbreeding mode. The results indicated that,for the same crossbreeding mode,the growth rate of progeny was in order F3> F2> F1; for the F3 progeny,the combinations Dorset- Borderdale- Small tail Han sheep and Dorset- Borderdale- Mongolia sheep gave a higher growth rate,with a body weight of 1. 57%,3. 17%,8. 23%,1. 15% higher in male and female individuals than the counterparts of Dorset and Tan sheep and Small tail Han sheep; for the F2 progeny,the combinations Dorset- Borderdale- Small tail Han sheep and Dorset- Borderdale- Mongolia sheep also gave a higher growth rate,with a body weight of 2. 15%,4. 53%,9. 21% and 2. 75% higher in male and female individuals than the counterparts of Dorset and Tan sheep and Small tail Han sheep; for the F1 progeny,the combination Borderdale and Small tail Han sheep assumed a higher growth rate,with a body weight of 3. 23%,6. 07%,7. 42% and 8. 66% higher in male and female individuals than the counterparts of Borderdale- Mongolia sheep and Tan sheep- Small tail Han sheep,respectively. Therefore,in the Small-tail Han sheep and Mongolia sheep producing regions,the F2 or F3progeny bred by using Dorset or Borderdale sheep as male parent to cross with local breeds,or the hybrid lambs of Small-tail Han sheep and Borderdale sheep as highly qualified commodity,would produce significant economic benefit. Moreover,the novel breeds obtained by crossing were the valuable genetic resource for breeding meat sheep.

  1. Kleingrass (Panicum coloratum L.) poisoning in sheep.

    Science.gov (United States)

    Bridges, C H; Camp, B J; Livingston, C W; Bailey, E M

    1987-11-01

    Twenty-four lambs grazing pastures of Panicum coloratum developed photosensitization secondary to hepatic dysfunction. Lesions were necrosis of scattered hepatocytes, obstruction of small bile ducts and bile canaliculi by small aggregates of birefringent crystals, and accumulation of birefringent crystals in phagocytes within sinusoids. The number of crystals in livers of affected sheep varied, depending on the amount of time of exposure to toxic plants and severity of hepatic abnormalities. Crystals in the liver were soluble in acidified ethyl alcohol, acetic acid, pyridine, chloral hydrate, and methanol, but not in xylene, petroleum ether, diethyl ether, acetone, water, or cold ethyl alcohol. Crystals were not stained by oil red O. There was necrosis of epithelial cells in renal distal convoluted tubules, papillary muscles of the heart, and the adrenal cortex. Lesions of Panicum coloratum-associated disease are similar to those associated with photosensitization induced by Tribulus terrestris, Agave lecheguilla, and Nolina texana.

  2. Targeted Editing of Myostatin Gene in Sheep by Transcription Activator-like Effector Nucleases.

    Science.gov (United States)

    Zhao, Xinxia; Ni, Wei; Chen, Chuangfu; Sai, Wujiafu; Qiao, Jun; Sheng, Jingliang; Zhang, Hui; Li, Guozhong; Wang, Dawei; Hu, Shengwei

    2016-03-01

    Myostatin (MSTN) is a secreted growth factor expressed in skeletal muscle and adipose tissue that negatively regulates skeletal muscle mass. Gene knockout of MSTN can result in increasing muscle mass in sheep. The objectives were to investigate whether myostatin gene can be edited in sheep by transcription activator-like effector nucleases (TALENs) in tandem with single-stranded DNA oligonucleotides (ssODNs). We designed a pair of TALENs to target a highly conserved sequence in the coding region of the sheep MSTN gene. The activity of the TALENs was verified by using luciferase single-strand annealing reporter assay in HEK 293T cell line. Co-transfection of TALENs and ssODNs oligonucleotides induced precise gene editing of myostatin gene in sheep primary fibroblasts. MSTN gene-edited cells were successfully used as nuclear donors for generating cloned embryos. TALENs combined with ssDNA oligonucleotides provide a useful approach for precise gene modification in livestock animals.

  3. Twin vaginal delivery: innovate or abdicate.

    Science.gov (United States)

    Easter, Sarah Rae; Taouk, Laura; Schulkin, Jay; Robinson, Julian N

    2017-02-07

    Neonatal safety data along with national guidelines have prompted renewed interest in vaginal delivery of twins, particularly in the case of the noncephalic second twin. Yet, the rising rate of twin cesarean deliveries, coupled with the national decline in operative obstetrics, raises concerns about the availability of providers who are skilled in twin vaginal birth. Providers are key stakeholders for increasing rates of twin vaginal delivery. We surveyed a group of practicing obstetricians to explore potential barriers to the vaginal birth of twins with a focus on delivery of the noncephalic second twin. Among 107 responding providers, only 57% would deliver a noncephalic second twin by breech extraction. Providers who preferred breech extraction had a higher rate of maternal-fetal medicine subspecialty training (26.2% vs 4.3%; P30 sets of twins annually (57.4% vs 34.8%; P=.02). Most providers (54.2%) were familiar with the findings from the recent randomized trial that demonstrated the safety of twin vaginal birth. However, knowledge of the trial was not associated statistically with a preference for breech extraction (62.3% vs 43.5%; P=.05). Providers who preferred breech extraction were more likely to agree with recent society guidelines that encourage the vaginal birth of twins (86.9% vs 63.0%; Pinnovation. Without novel provider-focused strategies, we may relinquish passively the requisite skills for not only our patients but also for future generations of obstetricians.

  4. Fetal growth disorders in twin gestations.

    LENUS (Irish Health Repository)

    Breathnach, Fionnuala M

    2012-06-01

    Twin growth is frequently mismatched. This review serves to explore the pathophysiologic mechanisms that underlie growth aberrations in twin gestations, the prenatal recognition of abnormal twin growth, and the critical importance of stratifying management of abnormal twin growth by chorionicity. Although poor in utero growth of both twins may reflect maternal factors resulting in global uteroplacental dysfunction, discordant twin growth may be attributed to differences in genetic potential between co-twins, placental dysfunction confined to one placenta only, or one placental territory within a shared placenta. In addition, twin-twin transfusion syndrome represents a distinct entity of which discordant growth is a common feature. Discordant growth is recognized as an independent risk factor for adverse perinatal outcome. Intertwin birth weight disparity of 18% or more should be considered to represent a discordance threshold, which serves as an independent risk factor for adverse perinatal outcome. At this cutoff, perinatal morbidity is found to increase both for the larger and the smaller twin within a discordant pair. There remains uncertainty surrounding the sonographic parameters that are most predictive of discordance. Although heightening of fetal surveillance in the face of discordant twin growth follows the principles applied to singleton gestations complicated by fetal growth restriction, the timing of intervention is largely influenced by chorionicity.

  5. Using Twins to Better Understand Sibling Relationships.

    Science.gov (United States)

    Mark, Katharine M; Pike, Alison; Latham, Rachel M; Oliver, Bonamy R

    2017-03-01

    We compared the nature of the sibling relationship in dyads of varying genetic relatedness, employing a behavioural genetic design to estimate the contribution that genes and the environment have on this familial bond. Two samples were used-the Sisters and Brothers Study consisted of 173 families with two target non-twin children (mean ages = 7.42 and 5.22 years respectively); and the Twins, Family and Behaviour study included 234 families with two target twin children (mean age = 4.70 years). Mothers and fathers reported on their children's relationship with each other, via a postal questionnaire (the Sisters and Brothers Study) or a telephone interview (the Twins, Family and Behaviour study). Contrary to expectations, no mean level differences emerged when monozygotic twin pairs, dizygotic twin pairs, and non-twin pairs were compared on their sibling relationship quality. Behavioural genetic analyses also revealed that the sibling bond was modestly to moderately influenced by the genetic propensities of the children within the dyad, and moderately to substantially influenced by the shared environment common to both siblings. In addition, for sibling negativity, we found evidence of twin-specific environmental influence-dizygotic twins showed more reciprocity than did non-twins. Our findings have repercussions for the broader application of results from future twin-based investigations.

  6. TRAP Sequence - An Interesting Entity in Twins

    Directory of Open Access Journals (Sweden)

    R H Srinivas Prasad

    2012-01-01

    Full Text Available Twin reversed arterial perfusion (TRAP sequence, is a rare malformation occurring in monozygotic multiple gestations. One well-developed normal (pump twin and the other twin with absent cardiac structure (acardiac, who is hemodynamically dependent on the normal (pump twin are characteristic of this syndrome. The acardiac twin develops multiple anomalies that make survival difficult. The prognosis of the pump twin is variable with mortality rate ranging from 50% to 70%. Complications that affect the prognosis of the pump twin include complications of congestive cardiac failure due to increased cardiac demand, prematurity secondary to preterm delivery, and polyhydramnios. Because of these complications prompt detection, follow-up, and treatment of this condition is very important. We report two cases of TRAP sequence that emphasizes the importance of gray-scale and color Doppler imaging in diagnosis, detection of poor prognostic features, follow-up, and management of TRAP sequence.

  7. Do Twin Boundaries Always Strengthen Metal Nanowires?

    Science.gov (United States)

    Zhang, Yongfeng; Huang, Hanchen

    2009-01-01

    It has been widely reported that twin boundaries strengthen nanowires regardless of their morphology-that is, the strength of nanowires goes up as twin spacing goes down. This article shows that twin boundaries do not always strengthen nanowires. Using classical molecular dynamics simulations, the authors show that whether twin boundaries strengthen nanowires depends on the necessary stress for dislocation nucleation, which in turn depends on surface morphologies. When nanowires are circular cylindrical, the necessary stress of dislocation nucleation is high and the presence of twin boundaries lowers this stress; twin boundaries soften nanowires. In contrast, when nanowires are square cylindrical, the necessary stress of dislocation nucleation is low, and a higher stress is required for dislocations to penetrate twin boundaries; they strengthen nanowires.

  8. Do Twin Boundaries Always Strengthen Metal Nanowires?

    Directory of Open Access Journals (Sweden)

    Zhang Yongfeng

    2008-01-01

    Full Text Available Abstract It has been widely reported that twin boundaries strengthen nanowires regardless of their morphology—that is, the strength of nanowires goes up as twin spacing goes down. This article shows that twin boundaries do not always strengthen nanowires. Using classical molecular dynamics simulations, the authors show that whether twin boundaries strengthen nanowires depends on the necessary stress for dislocation nucleation, which in turn depends on surface morphologies. When nanowires are circular cylindrical, the necessary stress of dislocation nucleation is high and the presence of twin boundaries lowers this stress; twin boundaries soften nanowires. In contrast, when nanowires are square cylindrical, the necessary stress of dislocation nucleation is low, and a higher stress is required for dislocations to penetrate twin boundaries; they strengthen nanowires.

  9. The Levels of Genetic Differentiation of Small-Tailed Han Sheep and Tan Sheep Populations Using Structural Loci

    Institute of Scientific and Technical Information of China (English)

    LU Sheng-xia; CHANG Hong; JI De-jun; Tsunoda Kenji; REN Zhan-jun; REN Xiang-lian; SUN Wei; YANG Zhang-ping; CHANG Guo-bin

    2006-01-01

    Using the method of "random sampling in typical colonies of the central area of the habitat" and several electrophoresis techniques, the variations of 17 structural loci encoding blood proteins in 60 Small-Tailed Han sheep and 73 Tan sheep were examined and compared with those of 14 other sheep populations in China and other countries to investigate their levels of genetic differentiation. The average heterozygosities of Small-Tailed Han sheep and Tan sheep were 0.2360 and 0.2587, respectively. The average polymorphic information content values were 0.1974 and 0.2102, respectively. The average effective numbers of alleles were 1.5723 and 1.5751, respectively. The coefficients of gene differentiation in the four groups (including 4, 6, 13, and 16 sheep populations, respectively) were 0.049323, 0.059987, 0.1728, and 0.201256,respectively, indicating that the degree of gene differentiation at the structural loci was the least in Hu sheep, Tong sheep,Small-Tailed Han sheep, and Tan sheep; followed by the above-mentioned four sheep populations and two Mongolian sheep populations; and was the highest in sheep populations belonging to the Mongolian sheep group, South Asian sheep, and European sheep. The earlier researchers' conclusions that both Small-Tailed Han sheep and Tan sheep evolved from Mongolian sheep were further verified by the results of this study. Hu sheep, Tong sheep, Small-Tailed Han sheep, and Tan sheep were decreasingly affected by the bloodline of Mongolian sheep to different degrees. The relationships among sheep populations were not closely related to the geographical distances among sheep populations.

  10. The anemia of chronic renal failure in sheep. Response to erythropoietin-rich plasma in vivo.

    Science.gov (United States)

    Eschbach, J W; Mladenovic, J; Garcia, J F; Wahl, P W; Adamson, J W

    1984-01-01

    The hypoproliferative anemia in chronic renal failure has been assumed to be the result of decreased erythropoietin (Ep) production by the damaged kidney and of the shortening of erythrocyte survival. However, many in vitro studies suggest that erythropoietic inhibitors in uremic plasma may contribute to the anemia. To determine the in vivo relevance of uremic inhibitors, increasing amounts of Ep as Ep-rich plasma were infused into six uremic sheep, and their erythropoietic responses were compared with those of nine normal sheep receiving similar amounts of Ep-rich plasma. Three sheep were studied in both normal and uremic states. Ep-rich plasma was obtained from phenylhydrazine- and phlebotomy-induced anemic sheep. Stable uremia was created by subtotal nephrectomy. Erythropoiesis was quantitated by reticulocyte response, ferrokinetics (plasma iron turnover and marrow transit time), and by hemoglobin C synthesis. Ep-rich plasma stimulated erythropoiesis similarly in uremic and normal sheep, regardless of the degree of uremia. Nondialyzed uremic sheep responded as well as dialyzed animals. The anemia was corrected in the uremic dialyzed animals. The anemia was corrected in the uremic sheep after 15-40 daily infusions of Ep-rich plasma, the total dosage depending on the severity of the anemia. Polycythemia was induced when the infusions were continued. Reticulocytes, plasma iron turnover, and erythrocyte mass changes increased as the amount of Ep-rich plasma was increased. These dose-response effects, coupled with the identical erythropoietic response in normal and uremic sheep given the same amount of Ep-rich plasma, imply that there are no physiologically significant erythropoietic inhibitors in uremia. PMID:6746902

  11. A1M/α1-microglobulin protects from heme-induced placental and renal damage in a pregnant sheep model of preeclampsia.

    Directory of Open Access Journals (Sweden)

    Lena Wester-Rosenlöf

    Full Text Available Preeclampsia (PE is a serious pregnancy complication that manifests as hypertension and proteinuria after the 20(th gestation week. Previously, fetal hemoglobin (HbF has been identified as a plausible causative factor. Cell-free Hb and its degradation products are known to cause oxidative stress and tissue damage, typical of the PE placenta. A1M (α1-microglobulin is an endogenous scavenger of radicals and heme. Here, the usefulness of A1M as a treatment for PE is investigated in the pregnant ewe PE model, in which starvation induces PE symptoms via hemolysis. Eleven ewes, in late pregnancy, were starved for 36 hours and then treated with A1M (n = 5 or placebo (n = 6 injections. After injections, the ewes were re-fed and observed for additional 72 hours. They were monitored for blood pressure, proteinuria, blood cell distribution and clinical and inflammation markers in plasma. Before termination, the utero-placental circulation was analyzed with Doppler velocimetry and the kidney glomerular function was analyzed by Ficoll sieving. At termination, blood, kidney and placenta samples were collected and analyzed for changes in gene expression and tissue structure. The starvation resulted in increased amounts of the hemolysis marker bilirubin in the blood, structural damages to the placenta and kidneys and an increased glomerular sieving coefficient indicating a defect filtration barrier. Treatment with A1M ameliorated these changes without signs of side-effects. In conclusion, A1M displayed positive therapeutic effects in the ewe starvation PE model, and was well tolerated. Therefore, we suggest A1M as a plausible treatment for PE in humans.

  12. Emerging parasitic diseases of sheep.

    Science.gov (United States)

    Taylor, M A

    2012-09-30

    There have been changes in the emergence and inability to control of a number of sheep parasitic infections over the last decade. This review focuses on the more globally important sheep parasites, whose reported changes in epidemiology, occurrence or failure to control are becoming increasingly evident. One of the main perceived driving forces is climate change, which can have profound effects on parasite epidemiology, especially for those parasitic diseases where weather has a direct effect on the development of free-living stages. The emergence of anthelmintic-resistant strains of parasitic nematodes and the increasing reliance placed on anthelmintics for their control, can exert profound changes on the epidemiology of those nematodes causing parasitic gastroenteritis. As a consequence, the effectiveness of existing control strategies presents a major threat to sheep production in many areas around the world. The incidence of the liver fluke, Fasciola hepatica, is inextricably linked to high rainfall and is particularly prevalent in high rainfall years. Over the last few decades, there have also been increasing reports of other fluke associated diseases, such as dicroceliosis and paramphistomosis, in a number of western European countries, possibly introduced through animal movements, and able to establish with changing climates. External parasite infections, such as myiasis, can cause significant economic loss and presents as a major welfare problem. The range of elevated temperatures predicted by current climate change scenarios, result in an elongated blowfly season with earlier spring emergence and a higher cumulative incidence of fly strike. Additionally, legislative decisions leading to enforced changes in pesticide usage and choices have resulted in increased reports and spread of ectoparasitic infections, particularly mite, lice and tick infestations in sheep. Factors, such as dip disposal and associated environmental concerns, and, perhaps more

  13. Photosenitization of sheep on kleingrass pasture.

    Science.gov (United States)

    Muchiri, D J; Bridges, C H; Ueckert, D N; Bailey, E M

    1980-08-15

    The clinical appearance and serum gamma-glutamyl transpeptidase (GGT) activity were studied in 5 groups of sheep (12 per group) on kleingrass (Panicum coloratum) pasture plots and in 1 group of sheep (10 animals) on native buffalograss (Buchloë dactyloides) pasture. Eleven sheep (at least 1 from each group on kleingrass pasture plots) had elevated serum GGT activity. Seven of 11 sheep with elevated serum GGT activity developed signs of photosensitization. None of the sheep on buffalograss pasture developed signs of photosensitization or elevated GGT activity. The pathologic findings were similar in the sheep that had signs of photosensitization. Grossly, there was icterus and subcutaneous edema. The livers had tapeworms (Thysanosoma actinioides) in the bile ducts, were slightly swollen, and varied in color from yellow to ochre in severe cases of biliary system derangements. Microscopically, there was cholangitis.

  14. Long-Term Impacts of Foetal Malnutrition Followed by Early Postnatal Obesity on Fat Distribution Pattern and Metabolic Adaptability in Adult Sheep.

    Science.gov (United States)

    Khanal, Prabhat; Johnsen, Lærke; Axel, Anne Marie Dixen; Hansen, Pernille Willert; Kongsted, Anna Hauntoft; Lyckegaard, Nette Brinch; Nielsen, Mette Olaf

    2016-01-01

    We aimed to investigate whether over- versus undernutrition in late foetal life combined with obesity development in early postnatal life have differential implications for fat distribution and metabolic adaptability in adulthood. Twin-pregnant ewes were fed NORM (100% of daily energy and protein requirements), LOW (50% of NORM) or HIGH (150%/110% of energy/protein requirements) diets during the last trimester. Postnatally, twin-lambs received obesogenic (HCHF) or moderate (CONV) diets until 6 months of age, and a moderate (obesity correcting) diet thereafter. At 2½ years of age (adulthood), plasma metabolite profiles during fasting, glucose, insulin and propionate (in fed and fasted states) tolerance tests were examined. Organ weights were determined at autopsy. Early obesity development was associated with lack of expansion of perirenal, but not other adipose tissues from adolescence to adulthood, resulting in 10% unit increased proportion of mesenteric of intra-abdominal fat. Prenatal undernutrition had a similar but much less pronounced effect. Across tolerance tests, LOW-HCHF sheep had highest plasma levels of cholesterol, urea-nitrogen, creatinine, and lactate. Sex specific differences were observed, particularly with respect to fat deposition, but direction of responses to early nutrition impacts were similar. However, prenatal undernutrition induced greater metabolic alterations in adult females than males. Foetal undernutrition, but not overnutrition, predisposed for adult hypercholesterolaemia, hyperureaemia, hypercreatinaemia and hyperlactataemia, which became manifested only in combination with early obesity development. Perirenal expandability may play a special role in this context. Differential nutrition recommendations may be advisable for individuals with low versus high birth weights.

  15. Long-Term Impacts of Foetal Malnutrition Followed by Early Postnatal Obesity on Fat Distribution Pattern and Metabolic Adaptability in Adult Sheep.

    Directory of Open Access Journals (Sweden)

    Prabhat Khanal

    Full Text Available We aimed to investigate whether over- versus undernutrition in late foetal life combined with obesity development in early postnatal life have differential implications for fat distribution and metabolic adaptability in adulthood. Twin-pregnant ewes were fed NORM (100% of daily energy and protein requirements, LOW (50% of NORM or HIGH (150%/110% of energy/protein requirements diets during the last trimester. Postnatally, twin-lambs received obesogenic (HCHF or moderate (CONV diets until 6 months of age, and a moderate (obesity correcting diet thereafter. At 2½ years of age (adulthood, plasma metabolite profiles during fasting, glucose, insulin and propionate (in fed and fasted states tolerance tests were examined. Organ weights were determined at autopsy. Early obesity development was associated with lack of expansion of perirenal, but not other adipose tissues from adolescence to adulthood, resulting in 10% unit increased proportion of mesenteric of intra-abdominal fat. Prenatal undernutrition had a similar but much less pronounced effect. Across tolerance tests, LOW-HCHF sheep had highest plasma levels of cholesterol, urea-nitrogen, creatinine, and lactate. Sex specific differences were observed, particularly with respect to fat deposition, but direction of responses to early nutrition impacts were similar. However, prenatal undernutrition induced greater metabolic alterations in adult females than males. Foetal undernutrition, but not overnutrition, predisposed for adult hypercholesterolaemia, hyperureaemia, hypercreatinaemia and hyperlactataemia, which became manifested only in combination with early obesity development. Perirenal expandability may play a special role in this context. Differential nutrition recommendations may be advisable for individuals with low versus high birth weights.

  16. Zig-zag twins and helical phase transformations.

    Science.gov (United States)

    Ganor, Yaniv; Dumitrică, Traian; Feng, Fan; James, Richard D

    2016-04-28

    We demonstrate the large bending deformation induced by an array of permanent magnets (applied field ∼0.02 T) designed to minimize poles in the bent state of the crystal. Planar cantilevers of NiMnGa (5M modulated martensite) ferromagnetic shape memory alloy deform into an arched shape according to theory, with a zig-zag microstructure that complies with the kinematic and magnetic compatibility between adjacent twin variants. A general theory of bent and twisted states is given, applicable to both twinning and austenite/martensite transformations. Some of these configurations achieve order-of-magnitude amplification of rotation and axial strain. We investigate also atomistic analogues of these bent and twisted configurations with perfect interfaces between phases. These mechanisms of large deformation, induced by small magnetic fields or temperature changes, have potential application to the development of new actuation technologies for micro-robotic systems.

  17. Expression of functions by normal sheep alveolar macrophages and their alteration by interaction with Mycoplasma ovipneumoniae.

    Science.gov (United States)

    Niang, M; Rosenbusch, R F; Lopez-Virella, J; Kaeberle, M L

    1997-10-31

    Normal sheep alveolar macrophages collected by bronchial lavage were exposed to live or heat-killed Mycoplasma ovipneumoniae organisms, and their capability to ingest Staphylococcus aureus and to elicit antibody-dependent cellular cytotoxicity against sensitized chicken red blood cells was tested. Controls consisted of non-infected macrophages in M199 medium. In addition, the effect of M. ovipneumoniae on expression of surface molecules on these sheep alveolar macrophages was determined. The percentage of S. aureus ingested by nontreated sheep alveolar macrophages was significantly higher than that of infected macrophages. Live mycoplasmas were more effective in suppressing the ingestion of S. aureus by these macrophages than killed mycoplasmas. Both live and killed mycoplasmas suppressed the cytolytic effect of the sheep alveolar macrophages to a similar degree. About 78% and 45% of the normal sheep alveolar macrophages had IgG and complement receptors, respectively. Infection of these macrophages with M. ovipneumoniae decreased significantly the expression of IgG receptors but had no effects on complement receptors. There were substantial increases in the expression of both MHC class I and class II by the mycoplasma-induced macrophages as compared with unstimulated macrophages. Live mycoplasmas were more effective in inducing expression of both classes than killed mycoplasmas. The results, taken together, suggest that M. ovipneumoniae induced alterations in macrophage activities and this may be a contributing factor in the pathogenesis of respiratory disease induced by the organism.

  18. Royana: Successful Experience in Cloning the Sheep

    OpenAIRE

    Saeed Kazemi Ashtiani; Mohammad Hossein Nasr-Esfahani; Sayyed Mortaza Hosseini; Fariba Moulavi; Mahdi Hajian; Mohsen Frouzanfar; Parvaneh Abedi; Maryam Meamar; Mojtaba Rezazadeh Valojerdi; Hamid Gourabi; Abdolhossein Shahverdi; Hossein Baharvand; Ahmad Vosough Dizaj; Hossein Imani; Poopak Eftekhari-Yazdi

    2008-01-01

    Objective: This study describes our experiences in reproductive cloning using two differentprocedures resulting in birth of the first successfully cloned sheep in Iran and theMiddle-East, nick-named "Royana".Materials and Methods: Abattoir-derived sheep oocytes were enucleated after in vitromaturation for 18-20hrs and then reconstructed by ear-derived sheep somatic cells usingtwo different procedures of renucleation (subzonary, intracytoplasmic), embryo culture (coculture,sequential medium) a...

  19. Projections of population-based twinning rates through the year 2100.

    Science.gov (United States)

    Oleszczuk, J J; Keith, D M; Keith, L G; Rayburn, W F

    1999-11-01

    To present the first compilation of population-based twinning rates published after the year 1990 and to project population-based twinning rates through the year 2100. We searched the Internet-based MEDLINE database for articles published after 1990 in which population-based twinning rates were described. We used population-based data from national statistical authorities from Australia, Austria, Canada, Finland, Hong Kong, Israel, Japan, Norway, Singapore and Sweden, published by Y. Imaizumi in a recent article. U.S. figures were based on data from the National Center for Health Statistics. Annual growth rates of twinning were calculated and graphed, making the assumption that these rates would remain constant throughout the next century. Our report presents the most recent population-based twinning rates. When projected through the year 2015, twinning rates reach figures that could best be described as derived from a Jules Verne novel: Sweden, in this model, would have four times more twin than singleton births. We strongly suggest that physicians reexamine their patterns of prescribing ovulation-inducing agents, which carry a greatly increased risk of multiple pregnancy.

  20. Role of five-fold twin boundary on the enhanced mechanical properties of fcc Fe nanowires.

    Science.gov (United States)

    Wu, J Y; Nagao, S; He, J Y; Zhang, Z L

    2011-12-14

    The role of 5-fold twin boundary on the structural and mechanical properties of fcc Fe nanowire under tension is explored by classical molecular dynamics. Twin-stabilized fcc nanowire with various diameters (6-24 nm) are examined by tension tests at several temperatures ranging from 0.01 to 1100 K. Significant increase in the Young's modulus of the smaller nanowires is revealed to originate from the central area of quinquefoliolate-like stress-distribution over the 5-fold twin, rather than from the surface tension that is often considered as the main source of such size-effects found in nanostructures. Because of the excess compressive stress caused by crossing twin-boundaries, the atoms in the center behave stiffer than those in bulk and even expand laterally under axial tension, providing locally negative Poisson's ratio. The yield strength of nanowire is also enhanced by the twin boundary that suppresses dislocation nucleation within a fcc twin-domain; therefore, the plasticity of nanowire is initiated by strain-induced fcc→bcc phase transformation that destroys the twin structure. After the yield, the nucleated bcc phase immediately spreads to the entire area, and forms a multigrain structure to realize ductile deformation followed by necking. As temperature elevated close to the critical temperature between bcc and fcc phases, the increased stability of fcc phase competes with the phase transformation under tension, and hence dislocation nucleations in fcc phase are observed exclusively at the highest temperature in our study.

  1. Sheep Feed and Scrapie, France

    Science.gov (United States)

    Philippe, Sandrine; Ducrot, Christian; Roy, Pascal; Remontet, Laurent; Jarrige, Nathalie

    2005-01-01

    Scrapie is a small ruminant, transmissible spongiform encephalopathy (TSE). Although in the past scrapie has not been considered a zoonosis, the emergence of bovine spongiform encephalopathy, transmissible to humans and experimentally to sheep, indicates that risk exists for small ruminant TSEs in humans. To identify the risk factors for introducing scrapie into sheep flocks, a case-control study was conducted in France from 1999 to 2000. Ninety-four case and 350 control flocks were matched by location and main breed. Three main hypotheses were tested: direct contact between flocks, indirect environmental contact, and foodborne risk. Statistical analysis was performed by using adjusted generalized linear models with the complementary log-log link function, considering flock size as an offset. A notable effect of using proprietary concentrates and milk replacers was observed. The risk was heterogeneous among feed factories. Contacts between flocks were not shown to be a risk factor. PMID:16102318

  2. Fingerprint recognition with identical twin fingerprints.

    Directory of Open Access Journals (Sweden)

    Xunqiang Tao

    Full Text Available Fingerprint recognition with identical twins is a challenging task due to the closest genetics-based relationship existing in the identical twins. Several pioneers have analyzed the similarity between twins' fingerprints. In this work we continue to investigate the topic of the similarity of identical twin fingerprints. Our study was tested based on a large identical twin fingerprint database that contains 83 twin pairs, 4 fingers per individual and six impressions per finger: 3984 (83*2*4*6 images. Compared to the previous work, our contributions are summarized as follows: (1 Two state-of-the-art fingerprint identification methods: P071 and VeriFinger 6.1 were used, rather than one fingerprint identification method in previous studies. (2 Six impressions per finger were captured, rather than just one impression, which makes the genuine distribution of matching scores more realistic. (3 A larger sample (83 pairs was collected. (4 A novel statistical analysis, which aims at showing the probability distribution of the fingerprint types for the corresponding fingers of identical twins which have same fingerprint type, has been conducted. (5 A novel analysis, which aims at showing which finger from identical twins has higher probability of having same fingerprint type, has been conducted. Our results showed that: (a A state-of-the-art automatic fingerprint verification system can distinguish identical twins without drastic degradation in performance. (b The chance that the fingerprints have the same type from identical twins is 0.7440, comparing to 0.3215 from non-identical twins. (c For the corresponding fingers of identical twins which have same fingerprint type, the probability distribution of five major fingerprint types is similar to the probability distribution for all the fingers' fingerprint type. (d For each of four fingers of identical twins, the probability of having same fingerprint type is similar.

  3. The relationship between twin language, twins' close ties, and social competence.

    Science.gov (United States)

    Hayashi, Chisato; Mikami, Hiroshi; Nishihara, Reiko; Maeda, Chiho; Hayakawa, Kazuo

    2014-02-01

    This study investigated the relationship between twin language, twins' close ties, and social competence in a prospective longitudinal study. We hypothesized that twins whose tie is close would be more likely to develop a twin language, and these twins would be less likely to develop social competence. In addition, we hypothesize that some environmental factors, such as having an older sibling, preschool attendance, zygosity, and sex are also related to twin language, twins' close ties, and social competence. At baseline in 1999 a mailed questionnaire survey was conducted, and a follow-up questionnaire was distributed in 2004 among 958 mothers. As a result, 516 respondents returned the questionnaire (53.9%). In this study, we used 261 twin pairs aged from 6 to 12 years (school-age children) for analysis, excluding those with missing values. In the present study, we found that zygosity and sex were associated with twins' close ties. Having an older sibling and preschool attendance did not affect the twins' close tie, twin language, or social competence. One of the most important findings was that social competence was not affected directly by twins' close tie, but was affected when a twin language was found.

  4. Isolation of Leptospira noguchii from sheep.

    Science.gov (United States)

    Silva, Everton F; Brod, Claudiomar S; Cerqueira, Gustavo M; Bourscheidt, Débora; Seyffert, Núbia; Queiroz, Adriano; Santos, Cleiton S; Ko, Albert I; Dellagostin, Odir A

    2007-03-31

    The main goal of this study was to obtain new isolates of Leptospira spp. from sheep. A total of 10 kidney samples and 44 blood samples were collected from sheep slaughtered in Pelotas, Southern Brazil. One isolate was obtained which was identified by 16S rRNA gene sequencing and serogrouping to be Leptospira noguchii serogroup Autumnalis. Microscopic agglutination test (MAT) evaluation revealed that 4.5% of the sheep sera reacted against the Autumnalis serogroup. This is the first report of isolation of L. noguchii from sheep. Together these findings indicate that L. noguchii infections may be a potentially important veterinary problem in this domestic animal species.

  5. The Spread of Substance Use and Delinquency between Adolescent Twins

    Science.gov (United States)

    Laursen, Brett; Hartl, Amy C.; Vitaro, Frank; Brendgen, Mara; Dionne, Ginette; Boivin, Michel

    2017-01-01

    This investigation examines the spread of problem behaviors (substance use and delinquency) between twin siblings. A sample of 628 twins (151 male twin pairs and 163 female twin pairs) drawn from the Quebec Newborn Twin Study completed inventories describing delinquency and substance use at ages 13, 14, and 15. A 3-wave longitudinal actor-partner…

  6. Einstein's Clocks and Langevin's Twins

    CERN Document Server

    Weinstein, Galina

    2012-01-01

    In 1905 Einstein presented the Clock Paradox and in 1911 Paul Langevin expanded Einstein's result to human observers, the "Twin Paradox." I will explain the crucial difference between Einstein and Langevin. Einstein did not present the so-called "Twin Paradox." Later Einstein continued to speak about the clock paradox. Einstein might not have been interested in the question: what happens to the observers themselves. The reason for this could be the following; Einstein dealt with measurement procedures, clocks and measuring rods. Einstein's observers were measuring time with these clocks and measuring rods. Einstein might not have been interested in so-called biology of the observers, whether these observers were getting older, younger, or whether they have gone any other changes; these changes appeared to be out of the scope of his "Principle of relativity" or kinematics. The processes and changes occurring within observers seemed to be good for philosophical discussions. Later writers criticized Einstein's c...

  7. Identical twins in forensic genetics

    DEFF Research Database (Denmark)

    Tvedebrink, Torben; Morling, Niels

    2015-01-01

    The increase in the number of forensic genetic loci used for identification purposes results in infinitesimal random match probabilities. These probabilities are computed under assumptions made for rather simple population genetic models. Often, the forensic expert reports likelihood ratios, where...... published results accounting for close familial relationships. However, we revisit the discussion to increase the awareness among forensic genetic practitioners and include new information on medical and societal factors to assess the risk of not considering a monozygotic twin as the true perpetrator...

  8. Geographic Tongue in Monozygotic Twins

    OpenAIRE

    Shekhar M, Guna

    2014-01-01

    This article discusses a case of 5-year-old girl monozygotic twins who were suffering from geographic tongue (GT), a benign inflammatory disorder of the tongue which is characterized by circinate, irregular erythematous lesions on the dorsum and lateral borders of the tongue caused by loss of filiform papillae of the tongue epithelium. Whilst geographic tongue is a common entity, reports on this condition are uncommon in the literature. To best of our knowledge, this is the first report which...

  9. Conjoined omphalopagus twins: a casereport

    Directory of Open Access Journals (Sweden)

    Sheila Yadira Gómez-Murillo

    2014-11-01

    Full Text Available Multiple pregnancies are 3% of the total. The most frequent are dizygotic females, however, a small group of them are of monozygotic conjoined twins in some anatomical area. This attracts the attention of physicians because of the rarity of the condition and the difficulties as well as the ethical dilemmas for their treatment. We report a case of male Siamese omphalopagus. They were separated surgically at seven weeks of age. One of them lived six months.

  10. [Respiratory diseases in sheep due to Mycoplasma ovipneumoniae].

    Science.gov (United States)

    Masalski, N; Ivanov, I; Dikova, Ts; Pavlov, N

    1982-01-01

    Mycoplasma ovipneumoniae was isolated from sheep and lambs affected with a respiratory disease. It was established that the pneumonic disease caused by this organism was a severe one, with high mortality rate in young lambs. Adult sheep and older lambs remained chronically affected. Susceptibility varied, depending on the breed of the animals, some imported animals running a more severe course of the disease than the local ones. The disease was artificially induced in lambs at the joint infection with M. ovipneumoniae and P. haemolytica. The morphologic changes in the lungs consisted in a prevailing proliferation of the septal cells and polynuclear cells in the alveoli, an interseptal histiocyte proliferation, and a serous leukocyte infiltration.

  11. The effect of maternal undernutrition in early gestation on gestation length and fetal and postnatal growth in sheep.

    Science.gov (United States)

    Cleal, Jane K; Poore, Kirsten R; Newman, James P; Noakes, David E; Hanson, Mark A; Green, Lucy R

    2007-10-01

    In utero undernutrition in humans may result in cardiovascular (CV), metabolic, and growth adaptations. In sheep, maternal nutrient restriction during pregnancy, without effects on fetal or birth weight, results in altered CV control in the offspring. Adjustment of gestation length after undernutrition could be a strategy to enhance postnatal health/survival. The aim of this study was to determine in sheep the effect of a 50% reduction in maternal nutrient intake [undernutrition group (U) versus 100%, control group (C)] during 1-31 d of gestation (dGA) on gestation length and offspring size. By 28 dGA, U ewes had gained less weight than C, and twin-bearing ewes had gained less weight than singleton-bearing ewes regardless of group (p<0.05). In different-sex twin pairs, maternal undernutrition resulted in longer gestation compared with C (146.5+/-0.6 versus 144.6+/-0.6 d, p<0.05). Increased weight gain by weaning (20.8+/-0.8 versus 17.9+/-0.8 kg, p<0.05) was observed in U male twins. These findings suggest that the strategy (i.e. growth rate or length of time in utero) adopted by the fetus to enhance immediate survival depends on offspring number and sex. This is likely to reflect the degree of constraint imposed on the fetus.

  12. Thrombosis of anastomoses may affect the staging sequence of twin-twin transfusion syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Wijngaard, Jeroen P H M van den; Gemert, Martin J C van [Laser Center, Academic Medical Center-University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor-UCLA School of Medicine, Torrance, CA 90502 (United States)], E-mail: j.p.vandenwijngaard@amc.uva.nl

    2008-03-07

    Twin-twin transfusion syndrome (TTTS) is a severe complication of monozygotic (identical) twins, which share one single monochorionic placenta. It is caused by placental anastomoses which link the two fetoplacental circulations of the twins and allow a chronic net inter-twin transfusion to develop between the fetuses. Clinical presentation of TTTS manifestations has been classified into five different stages. In this paper, we used our computational model of TTTS and examined the possible differences between chronic and rapidly increasing inter-twin transfusion in the simulated TTTS staging sequence. Our results suggest that rapid alterations in the net inter-twin transfusion, e.g. due to thrombosis of placental anastomoses, may produce a different staging sequence than in TTTS caused by chronic inter-twin transfusion. These results may aid an improved knowledge of TTTS pathophysiology under conditions of a rapidly changing cardiovascular function, and contribute to the planning of optimal intervention under such circumstances. (note)

  13. Twins eye study in Tasmania (TEST): rationale and methodology to recruit and examine twins.

    Science.gov (United States)

    Mackey, David A; Mackinnon, Jane R; Brown, Shayne A; Kearns, Lisa S; Ruddle, Jonathan B; Sanfilippo, Paul G; Sun, Cong; Hammond, Christopher J; Young, Terri L; Martin, Nicholas G; Hewitt, Alex W

    2009-10-01

    Visual impairment is a leading cause of morbidity and poor quality of life in our community. Unravelling the mechanisms underpinning important blinding diseases could allow preventative or curative steps to be implemented. Twin siblings provide a unique opportunity in biology to discover genes associated with numerous eye diseases and ocular biometry. Twins are particularly useful for quantitative trait analysis through genome-wide association and linkage studies. Although many studies involving twins rely on twin registries, we present our approach to the Twins Eye Study in Tasmania to provide insight into possible recruitment strategies, expected participation rates and potential examination strategies that can be considered by other researchers for similar studies. Five separate avenues for cohort recruitment were adopted: (1) piggy-backing existing studies where twins had been recruited, (2) utilizing the national twin registry, (3) word-of-mouth and local media publicity, (4) directly approaching schools, and finally (5) collaborating with other research groups studying twins.

  14. The TWINS Science Data System after the launch of TWINS 1

    Science.gov (United States)

    Goldstein, J.; Valek, P.; Skoug, R.; Delapp, D.; Redfern, J.; Carruth, B.; McComas, D.

    2007-05-01

    The Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) 1 satellite is in orbit and science data are expected to commence in the near future. TWINS-1 comprises half of the TWINS stereoscopic neutral atom imaging system that will advance our knowledge of the Earth's ring current. To support the expected data return, we have developed a Science Data System (SDS) for the TWINS mission. The TWINS SDS is an IDL- and Java- driven data interface that operates primarily via a web browser, and has as its spine an SQL-queryable database. Through this interface, TWINS science data will be provided to the TWINS team, the space science community, and the public. In this paper we present the current and future capabilities of the TWINS SDS, as well as how the SDS fits into virtual observatory infrastructure.

  15. Chemoresistance to Valproate Treatment of Bovine Leukemia Virus-Infected Sheep; Identification of Improved HDAC Inhibitors.

    Science.gov (United States)

    Gillet, Nicolas; Vandermeers, Fabian; de Brogniez, Alix; Florins, Arnaud; Nigro, Annamaria; François, Carole; Bouzar, Amel-Baya; Verlaeten, Olivier; Stern, Eric; Lambert, Didier M; Wouters, Johan; Willems, Luc

    2012-10-08

    We previously proved that a histone deacetylase inhibitor (valproate, VPA) decreases the number of leukemic cells in bovine leukemia virus (BLV)-infected sheep. Here, we characterize the mechanisms initiated upon interruption of treatment. We observed that VPA treatment is followed by a decrease of the B cell counts and proviral loads (copies per blood volume). However, all sheep eventually relapsed after different periods of time and became refractory to further VPA treatment. Sheep remained persistently infected with BLV. B lymphocytes isolated throughout treatment and relapse were responsive to VPA-induced apoptosis in cell culture. B cell proliferation is only marginally affected by VPA ex vivo. Interestingly, in four out of five sheep, ex vivo viral expression was nearly undetectable at the time of relapse. In two sheep, a new tumoral clone arose, most likely revealing a selection process exerted by VPA in vivo. We conclude that the interruption of VPA treatment leads to the resurgence of the leukemia in BLV-infected sheep and hypothesize that resistance to further treatment might be due to the failure of viral expression induction. The development of more potent HDAC inhibitors and/or the combination with other compounds can overcome chemoresistance. These observations in the BLV model may be important for therapies against the related Human T-lymphotropic virus type 1.

  16. Chemoresistance to Valproate Treatment of Bovine Leukemia Virus-Infected Sheep; Identification of Improved HDAC Inhibitors

    Directory of Open Access Journals (Sweden)

    Nicolas Gillet

    2012-10-01

    Full Text Available We previously proved that a histone deacetylase inhibitor (valproate, VPA decreases the number of leukemic cells in bovine leukemia virus (BLV-infected sheep. Here, we characterize the mechanisms initiated upon interruption of treatment. We observed that VPA treatment is followed by a decrease of the B cell counts and proviral loads (copies per blood volume. However, all sheep eventually relapsed after different periods of time and became refractory to further VPA treatment. Sheep remained persistently infected with BLV. B lymphocytes isolated throughout treatment and relapse were responsive to VPA-induced apoptosis in cell culture. B cell proliferation is only marginally affected by VPA ex vivo. Interestingly, in four out of five sheep, ex vivo viral expression was nearly undetectable at the time of relapse. In two sheep, a new tumoral clone arose, most likely revealing a selection process exerted by VPA in vivo. We conclude that the interruption of VPA treatment leads to the resurgence of the leukemia in BLV-infected sheep and hypothesize that resistance to further treatment might be due to the failure of viral expression induction. The development of more potent HDAC inhibitors and/or the combination with other compounds can overcome chemoresistance. These observations in the BLV model may be important for therapies against the related Human T-lymphotropic virus type 1.

  17. Register-based research on twins

    DEFF Research Database (Denmark)

    Christensen, Kaare; Ohm Kyvik, Kirsten; Holm, Niels V

    2011-01-01

    Introduction: The Danish Twin Registry (DTR) has for more than 50 years been based on surveys and clinical investigations and over the two last decades also on register linkage. Currently these two approaches are merged within Statistics Denmark. Research topics: Here we report on three major...... groups of register-based research in the DTR that used the uniqueness of twinning. First, we focus on the ''long-term prognosis'' of being a twin compared with being a singleton and show that Danish twins have health trajectories in adulthood similar to singletons, which is a result of interest for twins...... and their families as well as a test of the fetal origins hypothesis that states that fetal growth restriction has long-term health consequences. Secondly, we summarise some of the most important register-based ''classical twin studies'', e.g. heritability studies on lifespan and exceptional longevity. Finally, we...

  18. Twin delivery: method, timing and conduct.

    Science.gov (United States)

    Barrett, Jon F R

    2014-02-01

    The incidence of twin pregnancy has increased worldwide over the past 10 years, largely as a consequence of the assisted reproductive technologies. Issues such as intrapartum monitoring and operative interventions, especially relating to the second twin, provide a unique challenge in labour and delivery. Epidemiological and cohort data suggest that twins have a three-fold higher mortality rate than singletons, and that the second twin might have a better outcome if delivered by lower segment caesarean section. The recently completed Twin Birth Study has found that planned vaginal lower segment caesarean section is not advantageous to the fetus. In the light of this large randomised-controlled trial, vaginal delivery if twin A presents by the vertex is recommended as long as guidelines for the conduct of such delivery are followed.

  19. A Twin Study of Perthes Disease

    DEFF Research Database (Denmark)

    Metcalfe, David; Van Dijck, Stephanie; Parsons, Nicolas

    2016-01-01

    and genetic associations with LCPD. METHODS: We extracted all twin pairs from the Danish Twin Registry (DTR) in which at least 1 individual had LCPD. The DTR captures every twin pair born alive in Denmark, and those with LCPD were identified by using health record linkage. Probanwise concordance.......00-0.18) for the dizygotic, and 0.18 (95% CI: 0.00-0.40) for the UZ twin pairs. CONCLUSIONS: This study found evidence of familial clustering in LCPD but did not show a genetic component. The absolute risk that a co-twin of an affected individual will develop LCPD is low, even in the case of monozygotic twin pairs.......BACKGROUND: Legg-Calvé-Perthes disease (LCPD) is an idiopathic avascular necrosis of the femoral head. Its etiology is poorly understood, although previous studies have implicated low birth weight and possible genetic determinants. The aim of this study was to identify potential birth weight...

  20. (120) and (122-bar) monazite deformation twins

    Energy Technology Data Exchange (ETDEWEB)

    Hay, R.S

    2003-10-20

    Unusual features of (120) and (122-bar) deformation twins in monazite (monoclinic LaPO{sub 4}) are described and analyzed. These features are kinks and other irregularities in (120) twins, and V-shaped indentations on (120) and (122-bar) twin planes. Twinning shear analysis suggests that the kinks are a type II deformation twin mode with shear direction ({eta}{sub 1}) of [21-bar0]. This complements previous analysis based on atom shuffling considerations. Shear strain compatibility requires extensive plastic deformation in the kink. The V-shaped indentations may be analogous to similar structures in b.c.c metal deformation twins. Deformation mechanisms that may be associated with these structures are discussed.

  1. Fullerton Virtual Twin Study: an update.

    Science.gov (United States)

    Segal, Nancy L; McGuire, Shirley A; Graham, Jamie L; Stohs, Joanne Hoven

    2013-02-01

    Virtual twins (VTs) are same-age unrelated siblings reared together from early infancy. These unique sibling sets replicate twinship, but without the genetic link. The first VT pair was identified and studied at the University of Minnesota in 1990, launching the development of the Fullerton Virtual Twin Study at California State University, Fullerton (CSUF) in 1991. The registry currently includes 151 pairs, mostly children, with new pairs identified on a continuous basis. Research with VTs includes studies of general intelligence, body size, interpersonal trust, social coordination, social networks, and parenting. In some cases, VTs have been studied in conjunction with pairs of monozygotic twins, dizygotic twins, full siblings, and friends as part of TAPS (Twins, Adoptees, Peers and Siblings), a collaborative project conducted between CSUF and the University of San Francisco, 2002-2006. VTs will also serve as a comparison group for epigenetic analyses of young Chinese twins reared apart and together.

  2. Twinning of Polymer Crystals Suppressed by Entropy

    Directory of Open Access Journals (Sweden)

    Nikos Ch. Karayiannis

    2014-09-01

    Full Text Available We propose an entropic argument as partial explanation of the observed scarcity of twinned structures in crystalline samples of synthetic organic polymeric materials. Polymeric molecules possess a much larger number of conformational degrees of freedom than low molecular weight substances. The preferred conformations of polymer chains in the bulk of a single crystal are often incompatible with the conformations imposed by the symmetry of a growth twin, both at the composition surfaces and in the twin axis. We calculate the differences in conformational entropy between chains in single crystals and chains in twinned crystals, and find that the reduction in chain conformational entropy in the twin is sufficient to make the single crystal the stable thermodynamic phase. The formation of cyclic twins in molecular dynamics simulations of chains of hard spheres must thus be attributed to kinetic factors. In more realistic polymers this entropic contribution to the free energy can be canceled or dominated by nonbonded and torsional energetics.

  3. Relationship of litter size with milk yield, udder morphology and udder health of East Friesian sheep

    Directory of Open Access Journals (Sweden)

    Zvonimir Prpić

    2016-12-01

    Full Text Available The aim of this study was to determine relationship between litter size and milk yield, udder morphology, and udder health of East Friesian ewes. For that purpose a total of 80 East Friesian ewes, from 2nd to 4th lactation, with symmetrical udders, without visible (clinical signs of mastitis were involved in this study. Until weaning at average age of 60±5 days lambs suckled their mothers exclusively. During milking period regular milking controls (on a monthly basis were carried out (AT method and, on these occasions, individual milk samples for chemical composition analysis were taken. Three times per lactation (1st, 3rd and 5th milking control, prior to the milking, evaluation and measuring of udder morphology traits were performed. Also, during above-mentioned test-day controls (three times per lactation one sample of half udder milk was taken with purpose of bacterial and somatic cell counts (SCC tests. Ewes with twin and triplet lambs had significantly (P0.05 and depth (P>0.05. Besides that, udders of ewes with twins and triplets had higher cistern, greater teat angle and larger teat dimensions than ewes with singles, although those differences were not statistically significant. Ewes with single lamb had teats more (P<0.05 cranially oriented than ewes with twins and triplets. Significant (P<0.05 differences in somatic cell count (log10SCC between ewes of different litter sizes were determined, regardless of the health status of mammary gland. The higher (P<0.05 prevalence of subclinical mastitis was observed in ewes with twin and triplet lambs than in ewes with singles. In 46% of mammary glands (udder halves of sheep with twins and triplets a subclinical mastitis was established and even 65.8% of them undergone an infection of one or both halves of the udder during the milking period.

  4. An ecologic study comparing distribution of Pasteurella trehalosi and Mannheimia haemolytica between Sierra Nevada bighorn sheep, White Mountain bighorn sheep, and domestic sheep.

    Science.gov (United States)

    Tomassini, Letizia; Gonzales, Ben; Weiser, Glen C; Sischo, William

    2009-10-01

    The prevalence and phenotypic variability of Pasteurella and Mannheimia isolates from Sierra Nevada bighorn sheep (Ovis canadensis sierrae), White Mountain bighorn sheep (Ovis canadensis nelsoni), and domestic sheep (Ovis aries) from California, USA, were compared. The White Mountain bighorn sheep population had a recent history of pneumonia-associated mortality, whereas the Sierra Nevada bighorn sheep population had no recent history of pneumonia-associated mortality. The domestic sheep flocks were pastured in areas geographically near both populations but were not known to have direct contact with either bighorn sheep population. Oropharyngeal swab samples were collected from healthy domestic and bighorn sheep and cultured to characterize bacterial species, hemolysis, biogroups, and biovariants. Pasteurella trehalosi and Mannheimia haemolytica were detected in all of the study populations, but the relative proportion of each bacterial species differed among sheep populations. Pasteurella trehalosi was more common than M. haemolytica in the bighorn sheep populations, whereas the opposite was true in domestic sheep. Mannheimia haemolytica was separated into 11 biogroups, and P. trehalosi was characterized into two biogroups. Biogroup distributions for M. haemolytica and P. trehalosi differed among the three populations; however, no difference was detected for the distribution of P. trehalosi biogroups between the Sierra Nevada bighorn sheep and domestic sheep. The prevalence odds ratios (pOR) for the distribution of M. haemolytica biogroups suggested little difference between White Mountain bighorn sheep and domestic sheep compared with Sierra Nevada bighorn sheep and domestic sheep, although these comparisons had relatively large confidence intervals for the point estimates. Hemolytic activity of the isolates was not different among the sheep populations for M. haemolytica but was different for P. trehalosi. No clear evidence of association was found in the

  5. Expression of inflammatory cytokine and inducible nitric oxide synthase genes in the small intestine and mesenteric lymph node tissues of pauci- and multibacillary sheep naturally infected with Mycobacterium avium ssp. paratuberculosis

    Directory of Open Access Journals (Sweden)

    Ganesh G Sonawane

    2016-01-01

    Conclusion: The present study indicated that IFN-γ and iNOS were found to play important role in the induction of Th1 type immune response in PB sheep. MB sheep had significant reduction in expression of IFN-γ and iNOS and elevation of IL-10 and TGF-β, which was typical of Th2 cytokine pattern. Elevated expression of IL-10 and TGF-β in PB cases possibly suggests the role of T-regulatory cells and may follow an independent mechanism not typical of Th1 pattern. In view of significantly reduced expression in both forms of the disease, IL-1α may not be an important cytokine in ovine paratuberculosis.

  6. Anaesthesia for the separation of conjoined twins

    Directory of Open Access Journals (Sweden)

    Jaya Lalwani

    2011-01-01

    Full Text Available Thoraco-omphalopagus is one of the most common type of conjoint twins accounting for 74% cases of conjoint twins. We report the anaesthetic management for successful separation of thoraco-omphalopagus conjoint twins, both of them surviving till date. We highlight the responsibility of anaesthesia team in anaesthetising the two individual patients simultaneously, need of careful monitoring and anticipation of complications like massive blood loss, hypotension, hypokalemia, hypoxia and hypercabia. Detailed description of successful management is reported.

  7. Idiopathic intracranial hypertension in female homozygous twins.

    OpenAIRE

    Fujiwara, S; Sawamura, Y; Kato, T.; Abe, H.; Katusima, H

    1997-01-01

    The authors report on female homozygous twins with idiopathic intracranial hypertension. At the age of 12 years, both twins simultaneously developed visual disturbances with photophobia. At the age of 19 years, an ophthalmological examination disclosed papilloedema in both their eyes. At the age of 22 years, a lumbar puncture showed raised CSF pressure over (200 mm H2O) in both twins. Their neurological and radiological examinations were extremely similar; both of them had severely impaired v...

  8. Culture systems: embryo culture and monozygotic twinning.

    Science.gov (United States)

    Sparks, Amy E

    2012-01-01

    The incidence of monozygotic twinning in pregnancies achieved with assisted reproductive technologies (ART) is significantly higher than spontaneously conceived pregnancies. The factors associated with ART that predispose the embryos to splitting are not well-characterized. Assisted hatching and extended embryo culture are two ART laboratory methods that have been risk factors for monozygotic twinning. The methods and strategies that may be employed to avoid monozygotic twinning are discussed in this chapter.

  9. College-age twins: university admission policies / twin research: birth weight and neuromotor performance; transfusion syndrome markers; vanishing twins and fetal sex determination; mz twin discordance for wilson's disease / media: big at birth; planned separation of conjoined twins; x factor twins; Cinema: the identical.

    Science.gov (United States)

    Segal, Nancy L

    2014-12-01

    There is a lack of research findings addressing the unique college admissions issues faced by twins and other multiples. The advantages and disadvantage twins face, as reported by college administrators, twins and families are reviewed. Next, recent research addressing twins' birth weight and neuromotor performance, transfusion syndrome markers, the vanishing twin syndrome and monozygotic (MZ) twin discordance for Wilson's disease is described. News items concerning the birth of unusually large twins, the planned separation of conjoined twins, twin participants in the X Factor games and a film, The Identical, are also summarized.

  10. The Solar Twin Planet Search II. A Jupiter twin around a solar twin

    CERN Document Server

    Bedell, M; Bean, J L; Ramirez, I; Asplund, M; Alves-Brito, A; Casagrande, L; Dreizler, S; Monroe, T; Spina, L; Maia, M Tucci

    2015-01-01

    Through our HARPS radial velocity survey for planets around solar twin stars, we have identified a promising Jupiter twin candidate around the star HIP11915. We characterize this Keplerian signal and investigate its potential origins in stellar activity. Our analysis indicates that HIP11915 hosts a Jupiter-mass planet with a 3600-day orbital period and low eccentricity. Although we cannot definitively rule out an activity cycle interpretation, we find that a planet interpretation is more likely based on a joint analysis of RV and activity index data. The challenges of long-period radial velocity signals addressed in this paper are critical for the ongoing discovery of Jupiter-like exoplanets. If planetary in nature, the signal investigated here represents a very close analog to the solar system in terms of both Sun-like host star and Jupiter-like planet.

  11. How does the inclusion of twins conceived via fertility treatments influence the results of twin studies?

    Science.gov (United States)

    Burt, S Alexandra; Klump, Kelly L

    2012-12-01

    Rates of twinning have risen dramatically over the last 30 years, from 1 in 53 births in 1980 to 1 in 30 births in 2009 (Martin et al. (January 2012). Three decades of twin births in the United States, 1980-2009. Atlanta, GA: Centers for Disease Control and Prevention, National Center for Health Statistics). This increase is largely attributable to increases in the use of fertility treatments (i.e., ovulation induction and in vitro fertilization) combined with delays in parenthood. Although this increase means that more twins are available for recruitment into twin studies, it also has potential consequences for the heritability estimates obtained in these studies. This study sought to evaluate this possibility, making use of the ongoing Michigan Twins Project (N = 7,261 families with twins aged 3-17 years), an arm of the Michigan State University Twin Registry. Results revealed that, on average, twins conceived via fertility treatments had lower rates of behavior problems than those conceived naturally, although these behavioral differences could be explained largely by demographic and socio-economic differences across the two types of twin families. Twin similarity did not meaningfully differ across fertility treatment status. We thus conclude that estimates of genetic and environmental influences obtained from twin studies over the last 10-15 years are more or less unaffected by the inclusion of twins conceived via fertility treatments in their samples.

  12. Rapid onset of severe twin-twin transfusion syndrome caused by placental venous thrombosis

    NARCIS (Netherlands)

    Nikkels, PGJ; van Gemert, MJC; Sollie-Szarynska, KM; Molendijk, H; Timmer, B; Machin, GA

    2002-01-01

    We report a case of rapid onset of severe twin-twin transfusion syndrome (TTTS) at 25 weeks gestation in a monochorionic twin pregnancy that was uneventful before that time. Thrombosis of a main venous branch draining several arteriovenous (AV) anastomoses to the donor changed the previous hemodynam

  13. Atomistic deformation mechanisms in twinned copper nanospheres.

    Science.gov (United States)

    Bian, Jianjun; Niu, Xinrui; Zhang, Hao; Wang, Gangfeng

    2014-01-01

    In the present study, we perform molecular dynamic simulations to investigate the compression response and atomistic deformation mechanisms of twinned nanospheres. The relationship between load and compression depth is calculated for various twin spacing and loading directions. Then, the overall elastic properties and the underlying plastic deformation mechanisms are illuminated. Twin boundaries (TBs) act as obstacles to dislocation motion and lead to strengthening. As the loading direction varies, the plastic deformation transfers from dislocations intersecting with TBs, slipping parallel to TBs, and then to being restrained by TBs. The strengthening of TBs depends strongly on the twin spacing.

  14. Vascular distribution patterns in monochorionic twin placentas.

    Science.gov (United States)

    De Paepe, M E; DeKoninck, P; Friedman, R M

    2005-07-01

    Several recent publications have focused on the association between the occurrence of twin-to-twin transfusion syndrome (TTTS) in diamniotic-monochorionic twins and the presence of a number of selected anatomic placental characteristics (distribution of vascular territory, cord insertion, type and number of inter-twin anastomoses). In contrast, the potential importance of the vascular distribution patterns of the individual twins remains to be elucidated. Based on its gross architectural distribution pattern, chorionic vasculature is traditionally described as disperse, magistral or mixed. The aim of this study was (1) to determine the relative prevalence of these vascular distribution patterns in monochorionic twin placentas, and (2) to correlate these patterns with the presence of TTTS and known anatomic placental features linked to TTTS. The placentas of 89 consecutive diamniotic-monochorionic twins (15 with TTTS, 74 without TTTS), examined at Women and Infants Hospital, were studied. Disperse vascular patterns were seen in 53% of twins, and magistral or mixed patterns in 47%. The prevalence of magistral/mixed vascular patterns was significantly higher in TTTS gestations than in non-TTTS gestations (60% versus 44%, Ppatterns and marginal/velamentous cord insertion, low number of inter-twin anastomoses, and uneven distribution of the vascular territories. These findings suggest that the magistral/mixed vascular distribution pattern may represent an important placental architectural feature contributing to the complex pathophysiology of TTTS.

  15. Invasive treatment in complicated monochorionic twin pregnancies

    DEFF Research Database (Denmark)

    Sundberg, Karin; Søgaard, Kirsten; Jensen, Lisa Neerup;

    2012-01-01

    Objective. Monochorionic twin pregnancies are associated with increased risk of severe complications. Umbilical cord occlusion (UCO) and fetoscopic selective laser coagulation (FSLC) are used as invasive treatment. The study aim was to document treatment indications and pregnancy outcome where UCO...... and FSLC were used for treating fetal discrepancies and twin-to-twin transfusion syndrome (TTTS). Design. Cohort study of all consecutively treated monochorionic twin pregnancies 2004-2010. Setting. Tertiary care center. Population. One hundred and twenty pregnancies treated by FSLC (55) or UCO (65...

  16. Milk production capacity of prolific Priangan sheep: Preweaning performance

    Directory of Open Access Journals (Sweden)

    Bess Tiesnamurti

    2002-12-01

    Full Text Available A study was conducted to investigate the milk production capacity and preweaning performance of the prolific Priangan sheep, at sheep breeding station of the Research Institute for Animal production, Bogor using 126 ewes during three lambing periods in three consecutive years. The milk production was estimated weekly, started at day 7 after lambing date, till lambs were weaned at 90 days of age. The results showed that total milk production was significantly affected (P<0.05 by parity and the number of lambs born with average daily milk production of 519.5 g head-1 day-1. Estimated total milk production was 43.6 kg/lactation (N = 126; SD = 7.8; CV = 19.4%; range = 28.7-53.6 kg. According to the dam parity, the highest milk production was estimated at third parity (40.1 kg head-1 lactation-1, whereas on the basis of litter size, ewes with twin born lamb had the highest production (39.9 kg head-1 lactation-1. The preweaning lamb performance (weaning weight and preweaning daily gain was significantly affected (P<0.05 by ewe parity, sex, litter size and type of birth and weaned, with the average weaning weight of 10.62 kg (N = 208; SD = 3.37; CV = 25.08% and 130.9 + 41.8 g head-1 day-1 (N = 208; SD = 33.5; CV = 31.26%, respectively. Where as lamb birth weight was significantly affected (P<0.05 by ewe parity, sex and the number of lambs bornwith average of 2.39 kg (N = 208; SD = 0.66; CV = 9.8%.

  17. Being Pregnant with Twins, Triplets and Other Multiples

    Science.gov (United States)

    ... twins, triplets and other multiples Being pregnant with twins, triplets and other multiples E-mail to a ... embryos that grow into two or more babies. Twins are called identical when one fertilized egg splits ...

  18. Problem in twin pregnancy: Findings of prenatal sonography and autopsy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Ah; Cho, Jeong Yeon; Song, Mi Jin; Min, Jee Yeon; Lee, Young Ho; Lee, Hak Jong; Chun, Yi Kyeong; Kim, Yee Jeong; Hong, Sung Ran [Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2001-12-15

    Multifetal gestations are high risk pregnancies with higher perinatal morbidity and mortality. Multifetal gestations are subject to unique complications including conjoined twins, twin-to-twin transfusion syndrome (TTTS), acardiac twins, twin embization of co-twin demise and heterotopic pregnancies. Prenatal sonographic diagnosis of types and complications of multifetal gestations is important for antenatal care and prediction of fetal outcome. This study was performed to present the prenatal ultrasonographic findings and pathologic findings of the unique complications of twin pregnancy. Acardia is a lethal anomaly occurring in 1% of monozygotic twin. The acardiac twin has a parasitic existence and depends on the donor (pump) twin for its blood supply via placental anastomoses and retrograde perfusion of umbilical cord. This twin reversed arterial perfusion (TRAP) sequence is a most extreme manifestation on the TTTS. Doppler verification reversed flow in umbilical cord of the acardiac twin confirms the diagnosis.

  19. Reproductive Performance of Balochi Sheep in Different Ecological Zones of Balochistan, Pakistan

    Directory of Open Access Journals (Sweden)

    Mudassar Jahan1,3, Mohammad Masood Tariq2*, Muhammad Azam Kakar3 and Abdul Waheed4

    2013-01-01

    Full Text Available The data on reproductive performance of Balochi sheep (n=150 kept at three Government sheep farms in Balochistan, Quetta (KSBFM (n=50, Loralai (SRCY (n=50 and Usta Mohammad (UMSF (n=50, under semi-intensive management system, were analyzed. General linear model was used for analyzing the data. The fixed effects in the model included location of flock, age, type of birth, sex of lamb and their interactions. The overall findings of reproductive traits such as fertility, prolificacy, single lambing, twinning rate, lambs born alive and sex ratio (male: female were 92.67, 101.33, 89.86, 10.14, 96.33% and 50.33:49.67, respectively. The highest value for twinning rate was recorded in UMSF (13.04% and the lowest in KSBFM (6.52%. All traits were significantly different (P0.05 between flocks. The overall results revealed that age of dam, age at first service (AFS, service period (SP, age at first lambing (AFL and lambing interval (LI were 1078±2.2, 579.61±0.6, 206.25±0.2, 731.67±0.3 and 256.60±0.3 days, respectively. The results of ANOVA showed that locations had significant effect (P<0.05 on AFS and SP; however lambing interval and age at first lambing were not affected. Age of ewe, type of birth, sex of lamb(s born and interaction between these factors did not influence the traits significantly. It was concluded that reproductive performance of Balochi sheep was modest so it is vital to improve management, nutritional and breeding practices at the farm.

  20. I. Intake by sheep and production characteristics

    African Journals Online (AJOL)

    were of a good quality and will sustain satisfactory levels of animal production, ... objective was to quantify the intake and diet quality selected by sheep and measure yields at a ... supplement rainfall to ensure that moisture stress was not a limiting factor ..... State with special reference to the energy requirements of sheep.

  1. Phase Field Modeling of Twinning in Indentation of Transparent Crystals

    Science.gov (United States)

    2011-09-01

    twin boundaries . Equilibrium configurations of deformed and twinned crystals are attained via direct energy minimization. The theory is framed in the...phases: (i) the original crystal (the parent) and (ii) the twin. Interfaces between phases are twin boundaries . Order parameter η generally exhibits the...following values: η(X, •) = 0∀X ∈ parent, = 1∀X ∈ twin, ∈ (0, 1)∀X ∈ twin boundaries . (1) In linear elasticity, kinematic field variables are

  2. Weak phonon scattering effect of twin boundaries on thermal transmission.

    Science.gov (United States)

    Dong, Huicong; Xiao, Jianwei; Melnik, Roderick; Wen, Bin

    2016-01-29

    To study the effect of twin boundaries on thermal transmission, thermal conductivities of twinned diamond with different twin thicknesses have been studied by NEMD simulation. Results indicate that twin boundaries show a weak phonon scattering effect on thermal transmission, which is only caused by the additional twin boundaries' thermal resistance. Moreover, according to phonon kinetic theory, this weak phonon scattering effect of twin boundaries is mainly caused by a slightly reduced average group velocity.

  3. Weak phonon scattering effect of twin boundaries on thermal transmission

    OpenAIRE

    Huicong Dong; Jianwei Xiao; Roderick Melnik; Bin Wen

    2016-01-01

    To study the effect of twin boundaries on thermal transmission, thermal conductivities of twinned diamond with different twin thicknesses have been studied by NEMD simulation. Results indicate that twin boundaries show a weak phonon scattering effect on thermal transmission, which is only caused by the additional twin boundaries’ thermal resistance. Moreover, according to phonon kinetic theory, this weak phonon scattering effect of twin boundaries is mainly caused by a slightly reduced averag...

  4. The state of the art of twinning, a concept analysis of twinning in healthcare.

    Science.gov (United States)

    Cadée, Franka; Nieuwenhuijze, Marianne J; Lagro-Janssen, A L M; De Vries, Raymond

    2016-10-26

    Inequities in health have garnered international attention and are now addressed in Sustainable Development Goal 3 (SDG3), which seeks to 'promote well-being for all'. To attain this goal globally requires innovative approaches, one of which is twinning. According to the International Confederation of Midwives, twinning focusses on empowering professionals, who can subsequently be change-agents for their communities. However, twinning in healthcare is relatively new and because the definition and understanding of twinning lacks clarity, rigorous monitoring and evaluation are rare. A clear definition of twinning is essential for the development of a scientific base for this promising form of collaboration. We conducted a Concept Analysis (CA) of twinning in healthcare using Morse's method. A qualitative study of the broad literature was performed, including scientific papers, manuals, project reports, and websites. We identified relevant papers through a systematic search using scientific databases, backtracking of references, and experts in the field. We found nineteen papers on twinning in healthcare. This included twelve peer reviewed research papers, four manuals on twinning, two project reports, and one website. Seven of these papers offered no definition of twinning. In the other twelve papers definitions varied. Our CA of the literature resulted in four main attributes of twinning in healthcare. First, and most frequently mentioned, was reciprocity. The other three attributes were that twinning: 2) entails the building of personal relationships, 3) is dynamic process, 4) is between two named organisations across different cultures. The literature also indicated that these four attributes, and especially reciprocity, can have an empowering effect on healthcare professionals. Based on these four attributes we developed the following operational definition: Twinning is a cross-cultural, reciprocal process where two groups of people work together to achieve joint

  5. [Social development of twins: the need for intervention to avoid adverse effects of twin language].

    Science.gov (United States)

    Hayashi, Chisato; Hayakawa, Kazuo; Maeda, Chiho; Nishihara, Reiko; Onoi, Miyuki

    2008-10-01

    Social competence is one of the most important accomplishments of human development, and this skill in human relationships is learned through communication. Therefore, it is considered that delays in language development could be a barrier to building human relationships and social competence. Although it is well known that there are delays in language development in twins compared with that of singletons, little is known about how these linguistic delays affect the development of social competence. Because twin language is a language that is unique to each pair of twins and cannot be understood by either their mother or others, it may be assumed that the social competence of twins who have a twin language is less than that of twins who don't have a twin language. Therefore, in this prospective longitudinal study we also investigated the relationship between twin language and social competence. A mailed questionnaire survey was conducted in 958 mothers as a follow-up of a study conducted in 2004. As a result, 522 respondents returned the questionnaire (53.9%). In this study, we used only 256 twins aged 6- 12-years-old (school-age children) for analysis, excluding those with missing values. Multiple logistic regression analysis was employed. In the second child of twins, a low birth weight, the appearance of twin language and gestosis of the mother were positively related with social unbalance (OR = 1.846, 2.022 and 1.903). On the other hand, with the first child, however, there was no such link. The present results indicate that twin language might influence social competence in school-age children. It has been believed that linguistic intervention is unnecessary, because most twin language disappears spontaneously. However, early intervention, for example linguistic assistance by public health nurses or psychologists and early enrollment in a preschool may be necessary for twins with a twin language, to avoid adverse consequences in social competence at school-age.

  6. Identical twins with differing forms of ventricular pre-excitation.

    Science.gov (United States)

    Bennett, D H; Gribbin, B; Birkhead, J S

    1978-01-01

    Identical 10-year-old twins, both with electrocardiograms showing a short PR interval and a normal QRS complex but with dramatically different electrophysiological characteristics, are described. One twin experienced episodes of rapid palpitation and on one occasion was resuscitated from ventricular fibrillation. An intracardiac electrophysiological study confirmed the presence of an atrioventricular nodal bypass tract and in addition revealed the presence of an accessory atrioventricular pathway, thus demonstrating that the patient had both the Lown-Ganong-Levine and Wolff-Parkinson-White syndromes. Re-entry tachycardia and atrial fibrillation, with a very rapid ventricular rate, were precipitated. After treatment with amiodarone, the patient became asymptomatic and a repeat study showed that the features of the atrioventricular nodal bypass tract were no longer present and though re-entry tachycardias using the accessory atrioventricular pathway could still be induced, their rates were slower than before treatment. The other twin, in spite of an identical surface electrocardiogram, was asmymptomatic. An electrophysiological study showed the features of an atrioventricular nodal bypass tract but there was no evidence of additional atrioventricular accessory connections and a tachycardia could not be induced. PMID:565206

  7. Haemophilus somnus (Histophilus somni) in bighorn sheep.

    Science.gov (United States)

    Ward, Alton C S; Weiser, Glen C; Anderson, Bruce C; Cummings, Patrick J; Arnold, Karen F; Corbeil, Lynette B

    2006-01-01

    Respiratory disease and poor lamb recruitment have been identified as limiting factors for bighorn-sheep populations. Haemophilus somnus (recently reclassified as Histophilus somni) is associated with respiratory disease in American bison, domestic sheep, and cattle. It is also harbored in their reproductive tracts and has been associated with reproductive failure in domestic sheep and cattle. Therefore, reproductive tract and lung samples from bighorn sheep were evaluated for the presence of this organism. Organisms identified as H. somnus were isolated from 6 of 62 vaginal but none of 12 preputial swab samples. Antigen specific to H. somnus was detected by immunohistochemical study in 4 of 12 formalin-fixed lung tissue samples of bighorn sheep that died with evidence of pneumonia. Notably, H. somnus was found in alveolar debris in areas of inflammation. The 6 vaginal isolates and 2 H. somnus isolates previously cultured from pneumonic lungs of bighorn sheep were compared with 3 representative isolates from domestic sheep and 2 from cattle. The profiles of major outer membrane proteins and antigens for all of the isolates were predominantly similar, although differences that may be associated with the host-parasite relationship and virulence were detected. The DNA restriction fragment length profiles of the bighorn-sheep isolates had similarities not shared with the other isolates, suggesting distinct phylogenetic lines. All of the isolates had similar antimicrobial profiles, but the isolates from the bighorn sheep produced less pigment than those from the domestic livestock, and growth of the former was not enhanced by CO2. Wildlife biologists and diagnosticians should be aware of the potential of these organisms to cause disease in bighorn sheep and of growth characteristics that may hinder laboratory detection.

  8. Haemodynamic resistance model of monochorionic twin pregnancies complicated by acardiac twinning

    Energy Technology Data Exchange (ETDEWEB)

    Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam(Netherlands); Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor University of California-Los Angeles Medical Center, Torrence, CA 9050 (United States); Nikkels, Peter G J [Department of Pathology, University Medical Center, Utrecht (Netherlands)

    2004-07-21

    An acardiac twin is a severely malformed monochorionic twin fetus that lacks most organs, particularly a heart. It grows during pregnancy, because it is perfused by its developmentally normal co-twin (called the pump twin) via a set of placental arterioarterial and venovenous anastomoses. The pump twin dies intrauterine or neonatally in about 50% of the cases due to congestive heart failure, polyhydramnios and prematurity. Because the pathophysiology of this pregnancy is currently incompletely understood, we modified our previous haemodynamic model of monochorionic twins connected by placental vascular anastomoses to include the analysis of acardiac twin pregnancies. We incorporated the fetoplacental circulation as a resistance circuit and used the fetal umbilical flow that perfuses the body to define fetal growth, rather than the placental flow as done previously. Using this modified model, we predicted that the pump twin has excess blood volume and increased mean arterial blood pressure compared to those in the acardiac twin. Placental perfusion of the acardiac twin is significantly reduced compared to normal, as a consequence of an increased venous pressure, possibly implying reduced acardiac placental growth. In conclusion, the haemodynamic analysis may contribute to an increased knowledge of the pathophysiologic consequences of an acardiac body mass for the pump twin. (note)

  9. Vascular programming in twins: the effects of chorionicity and fetal therapy for twin-to-twin transfusion syndrome.

    Science.gov (United States)

    Gardiner, H M; Barlas, A; Matsui, H; Diemert, A; Taylor, M J O; Preece, J; Gordon, F; Greenwald, S E; Hecher, K

    2012-06-01

    We assessed vascular programming in genetically identical monochorionic twin pairs with twin-to-twin transfusion syndrome (TTTS) treated differently in utero by serial amnioreduction or fetal laser arterial photocoagulation. This case-control study re-assessed four twin groups at median 11 years comprising 20 pairs of monochorionic diamniotic twins: nine treated by amnioreduction (TTTS-amnio) and eleven by laser (TTTS-laser) with seven monochorionic and six dichorionic control pairs. Outcome measures were current blood pressure (BP), brachio-radial arterial stiffness derived from pulse wave velocity (PWV), resting microcirculation (Flux) and response to heating and post-occlusive reactive hyperaemia measured using laser Doppler. Potential confounders [PWV and BP at first study, current height, weight, heart rate and twin type (ex-recipient, ex-donor or heavier/lighter of pair)] were accounted for by Mixed Linear Models statistical methodology. PWV dichorionic > monochorionic (P = 0.024); systolic and diastolic BP dichorionic > TTTS-amnio and TTTS-laser (P = 0.004, P = 0.02 and P = 0.005, P = 0.02, respectively). Within-twin pair pattern of PWV discordance was similar in laser treated and dichorionic controls (heavier-born > lighter), opposite to TTTS-amnio and monochorionic controls. Flux monochorionic > dichorionic (P = 0.044) and heavier > lighter-born (P = 0.024). TTTS-laser and dichorionic diamniotic showed greatest hyperaemic responses (dichorionic > TTTS-amnio or monochorionic controls (P = 0.007, P = 0.025). Hyperaemic responses were slower in heavier-born twins (P = 0.005). In summary, monochorionic twins had lower BP, arterial stiffness and increased resting vasodilatation than dichorionic twins implying shared fetal circulation affects vascular development. Vascular responses in laser-TTTS were similar to dichorionic and opposite to TTTS-amnio suggesting a lasting effect of fetal therapy on vascular health.

  10. Twin-Foucault imaging method

    Science.gov (United States)

    Harada, Ken

    2012-02-01

    A method of Lorentz electron microscopy, which enables observation two Foucault images simultaneously by using an electron biprism instead of an objective aperture, was developed. The electron biprism is installed between two electron beams deflected by 180° magnetic domains. Potential applied to the biprism deflects the two electron beams further, and two Foucault images with reversed contrast are then obtained in one visual field. The twin Foucault images are able to extract the magnetic domain structures and to reconstruct an ordinary electron micrograph. The developed Foucault method was demonstrated with a 180° domain structure of manganite La0.825Sr0.175MnO3.

  11. Fatique life and twinning in alphazirconium

    DEFF Research Database (Denmark)

    Warren, M.R.; Beevers, C.J.

    1970-01-01

    stress for {11−21} twinning of ~0.5 kg mm−2 in zirconium containing 0.003 wt pct O. During observations confined to internal grains it was found that increasing grain size and decreasing oxygen content favored the formation of fatigue damage in association with these {11−21} twins. In external grains...

  12. Fetal behavior in normal dichorionic twin pregnancy

    NARCIS (Netherlands)

    Mulder, E. J. H.; Derks, J. B.; de Laat, M. W. M.; Visser, G. H. A.

    2012-01-01

    Objectives: A prospective study was performed to compare fetal behavioral development in healthy dichorionic twins and singletons, and identify twin intra-pair associations (synchrony) of fetal movements and rest-activity cycles using different criteria to define synchrony. Subjects and methods: Twe

  13. A Danish Twin Study of Schizophrenia Liability

    DEFF Research Database (Denmark)

    Kläning, Ulla; Trumbetta, Susan L; Gottesman, Irving I

    2016-01-01

    We studied schizophrenia liability in a Danish population-based sample of 44 twin pairs (13 MZ, 31 DZ, SS plus OS) in order to replicate previous twin study findings using contemporary diagnostic criteria, to examine genetic liability shared between schizophrenia and other disorders, and to explo...

  14. Colorado Longitudinal Twin Study of Reading Disability

    Science.gov (United States)

    Wadsworth, Sally J.; DeFries, John C.; Olson, Richard K.; Willcutt, Erik G.

    2007-01-01

    The primary objectives of the present study are to introduce the Colorado Longitudinal Twin Study of Reading Disability, the first longitudinal twin study in which subjects have been specifically selected for having a history of reading difficulties, and to present some initial assessments of the stability of reading performance and cognitive…

  15. Cord entanglement in monoamniotic twin pregnancies

    DEFF Research Database (Denmark)

    Lyndrup, J; Schouenborg, Lars Øland

    1987-01-01

    Monoamniotic twin pregnancy involves a heavy risk of fatal umbilical cord entanglement. Two cases are reported. In the first case, both twins were found dead in the 36th week, and the monoamnionicity was recognized at birth. In the second case, the monoamnionicity was discovered during...

  16. Optimal nutrition for improved twin pregnancy outcome.

    Science.gov (United States)

    Goodnight, William; Newman, Roger

    2009-11-01

    Twin pregnancies contribute a disproportionate degree to perinatal morbidity, partly because of increased risks of low birth weight and prematurity. Although the cause of the morbidity is multifactorial, attention to twin-specific maternal nutrition may be beneficial in achieving optimal fetal growth and birth weight. Achievement of body mass index (BMI)-specific weight gain goals, micronutrient and macronutrient supplementation specific to the physiology of twin gestations, and carbohydrate-controlled diets are recommended for optimal twin growth and pregnancy outcomes. The daily recommended caloric intake for normal-BMI women with twins is 40-45 kcal/kg each day, and iron, folate, calcium, magnesium, and zinc supplementation is recommended beyond a usual prenatal vitamin. Daily supplementation of docosahexaenoic acid and vitamin D should also be considered. Multiple gestation-specific prenatal care settings with a focus on nutritional interventions improve birth weight and length of gestation and should be considered for the care of women carrying multiples. Antepartum lactation consultation can also improve the rate of postpartum breastfeeding in twin pregnancies. Twin gestation-specific nutritional interventions seem effective in improving the outcome of these pregnancies and should be emphasized in the antepartum care of multiple gestations. This review examines the available evidence and offers recommendations for twin pregnancy-specific nutritional interventions.

  17. Twin-Screw Extruders in Ceramic Extrusion

    Science.gov (United States)

    Wiedmann, Werner; Hölzel, Maria

    The machines mainly used for compounding plastics, chemicals and food are co-rotating, closely intermeshing twin-screw extruders. Some 30 000 such extruders are in use worldwide, about 1/3 are ZSKs from Coperion Werner & Pfleiderer, Stuttgart. In the chemical industry more and more batch mixers are being replaced by continuous twin-screw kneaders.

  18. Utilizing twins as controls for non-twin case-materials in genome wide association studies.

    Directory of Open Access Journals (Sweden)

    Andrea Ganna

    Full Text Available Twin registries around the globe have collected DNA samples from large numbers of monozygotic and dizygotic twins. The twin sample collections are frequently used as controls in disease-specific studies together with non-twins. This approach is unbiased under the hypothesis that twins and singletons are comparable in terms of allele frequencies; i.e. there are no genetic variants associated with being a twin per se. To test this hypothesis we performed a genome-wide association study comparing the allele frequency of 572,352 single nucleotide polymorphisms (SNPs in 1,413 monozygotic (MZ and 5,451 dizygotic (DZ twins with 3,720 healthy singletons. Twins and singletons have been genotyped using the same platform. SNPs showing association with being a twin at P-value < 1 × 10(-5 were selected for replication analysis in 1,492 twins (463 MZ and 1,029 DZ and 1,880 singletons from Finland. No SNPs reached genome-wide significance (P-value < 5 × 10(-8 in the main analysis combining MZ and DZ twins. In a secondary analysis including only DZ twins two SNPs (rs2033541 close to ADAMTSL1 and rs4149283 close to ABCA1 were genome-wide significant after meta-analysis with the Finnish population. The estimated proportion of variance on the liability scale explained by all SNPs was 0.08 (P-value=0.003 when MZ and DZ were considered together and smaller for MZ (0.06, P-value=0.10 compared to DZ (0.09, P-value=0.003 when analyzed separately. In conclusion, twins and singletons can be used in genetic studies together with general population samples without introducing large bias. Further research is needed to explore genetic variances associated with DZ twinning.

  19. 21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG ADMINISTRATION..., sheep's milk blue-mold, and blue-mold cheese from sheep's milk. (a) Description. (1) Roquefort...

  20. 'Biracial'-Looking Twins: A New Twin Type?/Twin Research: Twins with Cystic Teratomas; Sleep Quality and Body Mass Index; Previable Membrane Rupture/Print and Online Reports: Twins Born to a Sister Surrogate; NASA Twin Study; African-Cosmopolitan Twin Fashion Inspirations; Triplet Hockey Stars.

    Science.gov (United States)

    Segal, Nancy L

    2017-06-01

    Dizygotic (DZ) co-twins born to mothers and fathers from different racial or ethnic backgrounds often resemble one parent much more than the other. As such, these pairs comprise a unique subset of twins for investigating how others' responses to their different looks may affect their personalities and self-esteem. This article describes some of these twin pairs and some challenges of raising them, and suggests ways they may be used in research. Next, recent twin research on cystic teratomas, relations between sleep quality and body mass index, and previable membrane rupture is described. The final section concerns twins, twin studies, and related events in the media, namely: twins born to a sister surrogate, the NASA twin investigation, inspiring African-Cosmopolitan twins in fashion, and triplet Hockey Stars.

  1. Intoxicação experimental por Simarouba versicolor (Simaroubaceae em ovinos e indução de resistência ao consumo da planta Experimental poisoning by Simarouba versicolor (Simaroubaceae in sheep and induced resistance to consumption of the plant

    Directory of Open Access Journals (Sweden)

    Ariany C. Santos

    2013-03-01

    da planta pelos ovinos e, as folhas mantiveram sua toxicidade quando dessecadas.Simarouba versicolor St. Hil. is a semideciduous tree belonging to the Simaroubaceae family. An outbreak of poisoning in cattle by shoots of S. versicolor present in the pasture in Mato Grosso do Sul and experimental reproduction of the poisoning was described. This study aimed to verify experimentally whether sheep could be used as a clinical-pathological model in the study of the poisoning caused by S. versicolor, to determine if there develops resistance induced by ingestion of small and repeated doses of the leaves, and if the plant keeps its toxicity when dried. Two experiments were conducted: Experiment 1 with green leaves or dried and powdered leave of S. versicolor, given in single doses of 5g/kg, 5g/kg and 3g/kg to three sheep (Sheep 1, 2 and 3 respectively. Experiment 2 was made with different daily doses of dried and powdered leaves of S. versicolor; to four sheep was given 1.5g/kg, 0.75g/kg, 0.6g/kg and 0.3g/kg, and the positive control (Sheep 4 received 3g/kg. The administration was suspended when the animals showed clinical signs of poisoning. After twelve days of recovery, the surviving sheep were challenged with the same daily dose given previously, to assess the development of resistance. Clinical signs observed in both experiments were characterized by anorexia, congested ocular mucosa, polydipsia, drooling, loose stools which evolved into fetid greenish watery diarrhea, lateral decumbency and death of Sheep 1 to 7. The main histological lesions observed were necrosis of lymphoid tissue (lymph nodes, spleen, Peyer's patches and necrotizing enteritis. With the results it can be concluded that sheep can be used as experimental model for the clinic-pathological aspects of poisoning by S. versicolor. The method used has not shown resistance to the daily consumption of the plant by the sheep, and the leaves kept their toxicity when dried.

  2. Twins in Ancient Greece: a synopsis.

    Science.gov (United States)

    Malamitsi-Puchner, Ariadne

    2016-01-01

    This brief outline associates twins with several aspects of life in Ancient Greece. In Greek mythology twins caused ambivalent reactions and were believed to have ambivalent feelings for each other. Very often, they were viewed as the representatives of the dualistic nature of the universe. Heteropaternal superfecundation, which dominates in ancient myths, explains on one hand, the god-like qualities and, on the other hand, the mortal nature of many twins. An assumption is presented that legends referring to twins might reflect the territorial expansions of Ancient Greeks in Northern Mediterranean, around the Black Sea, in Asia Minor, as well as North East Africa. In conclusion, in Greek antiquity, twins have been used as transitional figures between myth and reality.

  3. Cosmological Signals of a Mirror Twin Higgs

    CERN Document Server

    Craig, Nathaniel; Trott, Timothy

    2016-01-01

    We investigate the cosmology of the minimal model of neutral naturalness, the mirror Twin Higgs. The softly-broken mirror symmetry relating the Standard Model to its twin counterpart leads to significant dark radiation in tension with BBN and CMB observations. We quantify this tension and illustrate how it can be mitigated in several simple scenarios that alter the relative energy densities of the two sectors while respecting the softly-broken mirror symmetry. In particular, we consider both the out-of-equilibrium decay of a new scalar as well as reheating in a toy model of twinned inflation, Twinflation. In both cases the dilution of energy density in the twin sector does not merely reconcile the existence of a mirror Twin Higgs with cosmological constraints, but predicts contributions to cosmological observables that may be probed in current and future CMB experiments. This raises the prospect of discovering evidence of neutral naturalness through cosmology rather than colliders.

  4. Highlights from the 15th International Congress of Twin Studies/Twin Research: Differentiating MZ Co-twins Via SNPs; Mistaken Infant Twin-Singleton Hospital Registration; Narcolepsy With Cataplexy; Hearing Loss and Language Learning/Media Mentions: Broadway Musical Recalls Conjoined Hilton Twins; High Fashion Pair; Twins Turn 102; Insights From a Conjoined Twin Survivor.

    Science.gov (United States)

    Segal, Nancy L

    2015-02-01

    Highlights from the 15th International Congress of Twin Studies are presented. The congress was held November 16-19, 2014 in Budapest, Hungary. This report is followed by summaries of research addressing the differentiation of MZ co-twins by single nucleotide polymorphisms (SNPs), an unusual error in infant twin-singleton hospital registration, twins with childhood-onset narcolepsy with cataplexy, and the parenting effects of hearing loss in one co-twin. Media interest in twins covers a new Broadway musical based on the conjoined twins Violet and Daisy Hilton, male twins becoming famous in fashion, twins who turned 102 and unique insights from a conjoined twin survivor. This article is dedicated to the memory of Elizabeth (Liz) Hamel, DZA twin who met her co-twin for the first time at age seventy-eight years. Liz and her co-twin, Ann Hunt, are listed in the 2015 Guinness Book of Records as the longest separated twins in the world.

  5. Pen size and parity effects on maternal behaviour of Small-Tail Han sheep.

    Science.gov (United States)

    Lv, S-J; Yang, Y; Dwyer, C M; Li, F-K

    2015-07-01

    The aim of this experiment was to study the effects of pen size and parity on maternal behaviour of twin-bearing Small-Tail Han ewes. A total of 24 ewes were allocated to a 2×2 design (six per pen), with parity (primiparous or multiparous) and pen size (large: 6.0×3.0 m; small: 6.0×1.5 m) as main effects at Linyi University, Shandong Province, China. Behaviour was observed from after parturition until weaning. All ewes were observed for 6 h every 5 days from 0700 to1000 h and from 1400 to 1700 h. Continuous focal animal sampling was used to quantify the duration of maternal behaviours: sucking, grooming and following as well as the frequency of udder accepting, udder refusing and low-pitched bleating. Oestradiol and cortisol concentrations in the faeces (collected in the morning every 5 days) were detected using EIA kits. All lambs were weighed 24 h after parturition and again at weaning at 35 days of age. The small pen size significantly reduced following (Pprimiparous ewes (Pprimiparous ewes (P<0.001), and ewes in small pens had higher faecal cortisol levels compared with ewes in larger pens (P<0.001). As lambs increased in age, the duration of maternal grooming, following and suckling as well as frequency of udder acceptance and low-pitched bleating all declined, and the frequency of udder refusing increased (P<0.001 for all). Ewe parity, but not pen size, affected lamb weight gain during the period of observation (P<0.001). This is the first study to show that pen size, interacting with parity, can affect the expression of maternal behaviour in sheep during lactation. The study is also the first to report on the maternal behaviour of Chinese native sheep breeds (Small-Tail Han sheep), with implications for the production of sheep in China.

  6. Experimental infection of sheeps with Newcastle disease virus induces immune response%新城疫病毒感染绵羊诱导免疫应答反应的实验研究

    Institute of Scientific and Technical Information of China (English)

    王善辉; 池贤凤; 李安; 高三阳; 李书光; 王文秀; 沈志强

    2011-01-01

    To test the possibility of Newcastle disease virus (NDV) as NDV associated vaccine vactor in sheep, two groups of sheep were inoculated intranasally and intratracheally with NDV-30 strain, respectively, and the clinical signs and viral replication were evaluated, for detection of anti-HN antibodies, neutralizing antibodies and NDV-specific IgG antibodies in serum were dectected by HI test, microneutralization test and ELISA test, respectively. The results showed that NDV-30 was attenuated in this unnatural host. Anti-HN antibodies, NDV specific antibodies and neutralizing antibodies were produced by both intranasal and intratracheal infection. That suggested NDV could be used as a host-range-restricted vaccine vector in sheep, and it might be more safety for sheep inoculated intratracheally compared to that of intranasal inoculation.%为探索新城疫病毒(NDV)作为羊病毒病疫苗载体的可行性,验证NDV感染绵羊的可能性,本研究采用NDV Clone-30株分别通过滴鼻和气管灌注两种途径接种绵羊,接种后观察临床症状,检测接种动物排毒情况,通过血凝抑制试验检测接种绵羊特异性血凝抑制抗体,ELISA试验检测接种绵羊血清特异性IgG抗体,微量中和试验检测接种绵羊血清中和抗体.研究结果表明,NDV在绵羊体内是非致病性的,并且通过两种接种途径在绵羊体内均可以产生血凝抑制抗体、NDV特异性IgG抗体和中和抗体反应.本研究结果表明NDV有可能作为宿主限制性疫苗载体用于预防无特效疫苗的羊类疾病,且与气管灌注接种途径比,滴鼻接种途径相对安全.

  7. Modelling the influence of amnionicity on the severity of twin-twin transfusion syndrome in monochorionic twin pregnancies

    Energy Technology Data Exchange (ETDEWEB)

    Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor University of California-Los Angeles Medical Center, Torrance, CA 90502 (United States); Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands)

    2004-03-21

    Clinical treatment for diamniotic-monochorionic twin-twin transfusion syndrome (TTTS) may include conversion of diamniotic pregnancies to a monoamniotic-monochorionic state by disrupting the amnion septum. We sought to test the underlying hypothesis, i.e. that a monoamniotic state reduces the severity of TTTS. With use of our previously developed mathematical model of two equal fetoplacental circulatory units connected by various sizes and types of placental anastomoses, we compared the haemodynamic and amniotic fluid dynamics of monoamniotic and diamniotic twins that develop TTTS. We used three anastomotic patterns that produce severe, moderate or mild forms of TTTS, respectively, in our diamniotic-monochorionic twin model. Monoamnionicity was modelled by adding the two amniotic fluid volumes and using the volume-averaged amniotic fluid osmolality. The results were as follows: for severe TTTS, small differences develop between diamniotic and monoamniotic donor twins in fetal urine production, swallowed volume, blood volume, blood pressures, net fetofetal transfusion, and blood and amniotic fluid osmolality. However, the circulatory imbalance between the monoamniotic twins deteriorates similar to that of diamniotic twins. The pathophysiological differences tend to disappear for milder TTTS. In conclusion, our model suggests that the uncommon finding of TTTS in monoamniotic twins is not due to the presence of a single amniotic sac. Rather, clinically significant differences in anastomotic patterns and the delayed or lack of identification of manifestations in monoamniotic twins account for the reduced rate of TTTS diagnosis. Based on these results we expect the clinical disruption of the amnion septum in diamniotic-monochorionic TTTS pregnancies to have only minimal benefits. (note)

  8. Changes in the relative inflammatory responses in sheep cells overexpressing of toll-like receptor 4 when stimulated with LPS.

    Directory of Open Access Journals (Sweden)

    Shoulong Deng

    Full Text Available BACKGROUND: Many groups of Gram-negative bacteria cause diseases harmful to sheep. TLR4 is an important Toll-like receptor (TLR which responds to common Gram-negative bacterial infections. Activation of TLR4 leads to the induction of inflammatory responses, which is a linkage between the innate and adaptive immune systems. A vector pTLR4-3S was constructed to overexpress TLR4 gene in sheep. In this study, effects of TLR4 overexpression on inflammation response under LPS stimulated were addressed in vivo and in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Sheep fetal fibroblasts were transfected with expression vector pTLR4-3S. Transgenic sheep were produced by microinjection of the constructed plasmids into fertilized eggs. Fetal fibroblasts, monocyte-macrophage and fibroblasts isolated from the transgenic sheep were stimulated by LPS. After that immunoactive factors (TNF-α, IL-10, IL-6, IL-8, IFN-γ, nitric oxide, phagocytize ability and adhesion were detected. Furthermore, transgenic sheep were intradermal injected of LPS in ear and observed pathological changes by HE strain. Overexpression of TLR4 gene was observed on transgenic cells and individuals. In vitro, TLR4 overexpression transgenic cells secreted Th1 and Th2 inducing cytokines with a strong LPS mediated inflammation response and promoting the secretion of nitric oxide, and then recovered to initial level. The phagocytosis index of monocyte/macrophage in transgenic sheep was higher than that of non-transgenic sheep (P<0.05. In vivo, tissue sections showed that transgenic individuals launched inflammation response more quickly. CONCLUSIONS/SIGNIFICANCE: Overexpression of TLR4 in transgenic sheep enhanced the clearance of invaded microbe through secretion of cytokines, activation of macrophage, oxidation damage and infiltration of neutrophil.

  9. Neonatal morbidity in growth-discordant monochorionic twins: comparison between the larger and the smaller twin.

    Science.gov (United States)

    Lopriore, Enrico; Sluimers, Carolien; Pasman, Suzanne A; Middeldorp, Johanna M; Oepkes, Dick; Walther, Frans J

    2012-08-01

    Fetal growth restriction in singletons has been shown to enhance fetal lung maturation and reduce the risk of respiratory distress syndrome due to increased endogenous steroid production. However, data on lung maturation in growth-discordant monochorionic (thus, identical) twins are lacking. Our objective was to compare the risk of severe neonatal morbidity between the larger and the smaller twin in monochorionic twins with birth weight discordance (BWD). We included in the study all consecutive monochorionic diamniotic pregnancies with severe BWD (≥25%) and two live-born twins delivered at our center (n=47 twin pairs). We compared the incidence of neonatal morbidity, particularly respiratory distress syndrome (RDS), and cerebral lesions between the larger and the smaller co-twin. The incidence of severe neonatal morbidity in the larger and smaller twin was 38% (18/47) and 19% (9/47), respectively (odds ratio (OR) 2.66, 95% confidence interval (CI) 0.94-7.44) and was due primarily to the higher incidence of RDS, 32% (15/47) and 6% (3/47), respectively (OR 6.88, 95% CI 1.66-32.83). In conclusion, this study shows that the larger twin in monochorionic twin pairs with BWD is at increased risk of severe neonatal morbidity, particularly RDS, compared to the smaller twin.

  10. NOTE: Thrombosis of anastomoses may affect the staging sequence of twin twin transfusion syndrome

    Science.gov (United States)

    van den Wijngaard, Jeroen P. H. M.; Ross, Michael G.; van Gemert, Martin J. C.

    2008-03-01

    Twin-twin transfusion syndrome (TTTS) is a severe complication of monozygotic (identical) twins, which share one single monochorionic placenta. It is caused by placental anastomoses which link the two fetoplacental circulations of the twins and allow a chronic net inter-twin transfusion to develop between the fetuses. Clinical presentation of TTTS manifestations has been classified into five different stages. In this paper, we used our computational model of TTTS and examined the possible differences between chronic and rapidly increasing inter-twin transfusion in the simulated TTTS staging sequence. Our results suggest that rapid alterations in the net inter-twin transfusion, e.g. due to thrombosis of placental anastomoses, may produce a different staging sequence than in TTTS caused by chronic inter-twin transfusion. These results may aid an improved knowledge of TTTS pathophysiology under conditions of a rapidly changing cardiovascular function, and contribute to the planning of optimal intervention under such circumstances. Supported in part by the European Community Euro-twin-2-twin project (JPHMvdW) and by the National Institutes of Health, grant HL40899 (MGR).

  11. Acardiac Twinning (Twin Reversed Arterial Perfusion Sequence: A Review of Prenatal Management

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2005-06-01

    Full Text Available Acardiac twinning, or the twin reversed arterial perfusion (TRAP sequence, occurs in 1% of monozygotic twins, or 1 in 35,000 births. It is caused by the development of arterioarterial vascular anastomoses between the umbilical arteries of monozygotic twins early in embryogenesis. The pump twin may be associated with congenital anomalies and chromosomal abnormalities. Therefore, it is recommended that prenatal genetic testing be offered whenever pregnancy is complicated by acardiac twinning. The treatment options for acardiac twinning include observation, medical management, amniodrainage, and invasive treatment such as hysterotomy with selective delivery of the acardiac twin, intrafetal ablation of the acardiac twin by alcohol, laser, thermocoagulation or radiofrequency, fetoscope-guided funicular occlusion by ligation, laser or thermocoagulation, and ultrasound-guided funicular occlusion by ligation, cord compression, thermocoagulation or intrafunicular embolization with foreign bodies. If invasive treatment is indicated, the simplicity, safety, and efficacy of the chosen technique should be considered. An intrafetal approach has been shown to be superior to a funicular occlusion approach. Ultrasound-guided intrafetal laser ablation or radiofrequency ablation is believed to be the treatment of choice based on currently available data. This review emphasizes the necessity to carefully search for any possible associated anomaly in the pump twin by both genetic testing and sonographic examination, and to prudently consider invasive treatment only in pregnancies which would potentially benefit from the prenatal intervention.

  12. Effect of co-twin gender on neurodevelopmental symptoms: a twin register study.

    Science.gov (United States)

    Eriksson, Jonna Maria; Lundström, Sebastian; Lichtenstein, Paul; Bejerot, Susanne; Eriksson, Elias

    2016-01-01

    Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are neurodevelopmental disorders thought to have both genetic and environmental causes. It has been hypothesized that exposure to elevated levels of prenatal testosterone is associated with elevated traits of ASD and ADHD. Assuming that testosterone levels from a dizygotic male twin fetus may lead to enhanced testosterone exposure of its co-twins, we aimed to test the prenatal testosterone hypothesis by comparing same-sex with opposite-sex dizygotic twins with respect to neurodevelopmental symptoms. Neuropsychiatric traits were assessed in a population-based twin cohort from the Child and Adolescent Twin Study in Sweden (CATSS). Parental interviews were conducted for 16,312 dizygotic twins, 9 and 12 years old, with the Autism-Tics, ADHD, and other Comorbidities inventory (A-TAC). Girls with a female co-twin had an increased risk of reaching the cut-off score for ADHD compared with girls with a male co-twin. Both boys and girls with a female co-twin displayed a larger number of traits related to attention deficit and repetitive and stereotyped behaviors than those with a male twin. In girls, this also extended to social interaction and the combined measures for ASD and ADHD, however, with small effect sizes. Our results are reverse to what would have been expected from the prenatal testosterone hypothesis but consistent with a previous study of ASD and ADHD traits in dizygotic twins. The seemingly protective effect for girls of having a twin brother may be an effect of parent report bias, but may also be an unexpected effect of sharing the intrauterine environment with a male co-twin.

  13. Effect of Magnetostatic Interactions on Twin Boundary Motion in NiMnGa Magnetic Shape Memory Alloy

    DEFF Research Database (Denmark)

    Heczko, Oleg; Vokoun, David; Kopecky, Vit

    2015-01-01

    We investigated the effect of magnetostatic interactions on the field-induced reorientation of martensite variants in Ni50.0Mn27.5Ga22.5. The reorientation, achieved by sweeping a single Type-II twin boundary along the sample, was triggered by a twinning stress of about 0.1 MPa. However, depending...... on the initial position of the twin boundary, the magnetic field providing the critical stress varied in the range 832 kA/m. By taking into account the variants sizes and their mutual interactions, we explained the observed dependence of the switching field on the location of the boundary. The resulting match...

  14. Rumen protozoa in South African sheep with a summary of the worldwide distribution of sheep protozoa

    Directory of Open Access Journals (Sweden)

    Dirk Booyse

    2011-02-01

    Full Text Available Protozoa species were identified in rumen contents of four domestic sheep (Ovis aries from South Africa. All animals were fed a forage diet which consisted of 50% lucerne and 50% teff hay. Ten new host records were identified, bringing the total number of species and forms observed in sheep in South Africa to 30. The occurrence and geographic distribution of ciliate protozoa in both domestic and wild sheep from around the world are summarised. It was found that 15 genera and 131 species occur in domestic sheep globally.

  15. RELATIONS BETWEEN INVITRO CYTOTOXICITY AND CROSS-LINKED DERMAL SHEEP COLLAGENS

    NARCIS (Netherlands)

    VANLUYN, MJA; VANWACHEM, PB; DAMINK, LO; DIJKSTRA, PJ; FEIJEN, J; NIEUWENHUIS, P

    Collagen-based biomaterials have found various applications in the biomedical field. However, collagen-based biomaterials may induce cytotoxic effects. This study evaluated possible cytotoxic effects of (crosslinked) dermal sheep collagen (DSC) using a 7-d-methylcellulose cell culture with human

  16. The effect of chorionicity and twin-to-twin delivery time interval on short-term outcome of the second twin

    DEFF Research Database (Denmark)

    Hjortø, Sofie; Nickelsen, Carsten; Petersen, Janne;

    2013-01-01

    Abstract Objectives: To investigate the effect of chorionicity and twin-to-twin delivery time interval on short-term outcome in the second twin. Additionally, to investigate predictors of adverse outcome in both twins. Methods: Data included vaginally delivered twins (≥ 36 weeks) from Copenhagen...... University Hospitals (2001-09). The association between delivery interval and adverse outcome parameters were compared for monochorionic (MC) and dichorionic (DC) twins by multiple linear regression. Predictors were studied by logistic regression. Results: There were 554 twin pairs: 57 MC and 485 DC. We...... found no difference in the decrease of pH (p = 0.912) and Apgar (p = 0.609) in relation to increasing time interval. Neonatal unit (NICU) admissions did not differ (p = 0.167). Apgar ≤ 7 (p twin, whereas first (p = 0.001) or second (p twin Apgar...

  17. Jaagsiekte sheep retrovirus proviral clone JSRV(JS7), derived from the JS7 lung tumor cell line, induces ovine pulmonary carcinoma and is integrated into the surfactant protein A gene.

    Science.gov (United States)

    DeMartini, J C; Bishop, J V; Allen, T E; Jassim, F A; Sharp, J M; de las Heras, M; Voelker, D R; Carlson, J O

    2001-05-01

    Ovine pulmonary carcinoma (OPC) is a contagious neoplasm of alveolar epithelial type II (ATII) or Clara cells caused by a type D/B chimeric retrovirus, jaagsiekte sheep retrovirus (JSRV). Here we report the isolation, sequencing, pathogenicity, and integration site of a JSRV provirus isolated from a sheep lung tumor cell line (JS7). The sequence of the virus was 93 to 99% identical to other JSRV isolates and contained all of the expected open reading frames. To produce virions and test its infectivity, the JS7 provirus (JSRV(JS7)) was cloned into a plasmid containing a cytomegalovirus promoter and transfected into 293T cells. After intratracheal inoculation with virions from concentrated supernatant fluid, JSRV-associated OPC lesions were found in one of four lambs, confirming that JSRV(JS7) is pathogenic. In JS7-cell DNA, the viral genome was inserted in the protein-coding region for the surfactant protein A (SP-A) gene, which is highly expressed in ATII cells, in an orientation opposite to the direction of transcription of the SP-A gene. No significant transcription was detected from either the viral or the SP-A gene promoter in the JS7 cell line at passage level 170. The oncogenic significance of the JSRV proviral insertion involving the SP-A locus in the JS7 tumor cell line is unknown.

  18. Paratuberculosis in sheep and goats.

    Science.gov (United States)

    Windsor, P A

    2015-12-14

    Paratuberculosis is a chronic insidious, often serious, disease of the global small ruminant industries, mainly causing losses from mortalities and reduced productivity on-farm, interference in trading and, in Australia, profound socio-economic impacts that have periodically compromised harmony of rural communities. The pathogenesis, diagnosis, impacts and disease management options for ovine and caprine paratuberculosis are reviewed, comparing current controls in the extensive management system for sheep in wool flocks in Australia with the semi-intensive system of dairy flocks/herds in Greece. Improved understanding of the immune and cellular profiles of sheep with varying paratuberculosis outcomes and the recognition of the need for prolonged vaccination and biosecurity is considered of relevance to future control strategies. Paratuberculosis in goats is also of global distribution although the prevalence, economic impact and strategic control options are less well recognized, possibly due to the relatively meagre resources available for goat industry research. Although there have been some recent advances, more work is required on developing control strategies for goats, particularly in dairy situations where there is an important need for validation of improved diagnostic assays and the recognition of the potential impacts for vaccination. For all species, a research priority remains the identification of tests that can detect latent and subclinical infections to enhance removal of future sources of infectious material from flocks/herds and the food chain, plus predict the likely outcomes of animals exposed to the organism at an early age. Improving national paratuberculosis control programs should also be a priority to manage disease risk from trade. The importance of strong leadership and communication, building trust within rural communities confused by the difficulties in managing this insidious disease, reflects the importance of change management

  19. The effect of chorionicity and twin-to-twin delivery time interval on short-term outcome of the second twin.

    Science.gov (United States)

    Hjortø, Sofie; Nickelsen, Carsten; Petersen, Janne; Secher, Niels Jørgen

    2014-01-01

    To investigate the effect of chorionicity and twin-to-twin delivery time interval on short-term outcome in the second twin as well as to investigate the predictors of adverse outcome in both twins. Data included vaginally delivered twins (≥36 weeks) from Copenhagen University Hospitals (2001-2009). The association between delivery interval and adverse outcome parameters was compared for monochorionic (MC) and dichorionic (DC) twins by multiple linear regression. Predictors were studied by logistic regression. There were 554 twin pairs, of which 57 were MC and 485 DC. We found no difference in the decrease of pH (p = 0.912) and Apgar (p = 0.609) in relation to increasing time interval. Neonatal unit (NICU) admissions did not differ (p = 0.167). Apgar ≤7 (p < 0.001) and pH ≤ 7.20 (p = 0.002) increased first twin risk of NICU admission, whereas first (p = 0.001) or second (p < 0.001) twin Apgar ≤7 and second twin pH ≤7.00 (p = 0.003) increased second twin risk of NICU admission. Increasing delivery interval was associated with a significant decrease in pH and Apgar, but there was no difference between MC and DC twins. Low Apgar of the first twin increased the risk of second twin NICU admission.

  20. Rare Complications with Monochorionic Twins: Ultrasonography and Pathology Correlations

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mi Jin [Cheil General Hospital and Women' s Healthcare Center, Kwandong University College of Medicine, Seoul (Korea, Republic of)

    2009-12-15

    We reviewed the sonographic features of rare complications with monochorionic twins and we correlated these features with the pathologic findings. The complications, including the twin reversed arterial perfusion sequence, the twin embolization syndrome, the conjoined twins and umbilical cord entanglement. A better understanding of these complications can aid making an accurate prenatal diagnosis and predicting the fetal outcome

  1. Dislocation Mechanism of Twinning in Ni-Mn-Ga

    Science.gov (United States)

    Zárubová, N.; Ge, Y.; Gemperlová, J.; Gemperle, A.; Hannula, S.-P.

    2012-03-01

    Tensile tests were performed in situ in a transmission electron microscope to investigate the twinning mechanism in non-modulated Ni-Mn-Ga martensite. The reorientation of the twin variants occurs via twinning dislocations. Their generation and movement were followed; the glide plane and Burgers vector were verified. Individual twinning dislocations were visualized.

  2. Outcome of twin pregnancies conceived after assisted reproductive techniques

    Directory of Open Access Journals (Sweden)

    A Baxi

    2008-01-01

    Full Text Available Context : There is a continuous controversy regarding the obstetric perinatal outcome of twin pregnancies conceived after assisted reproductive techniques (ART. There is an ongoing discussion whether theses parameters may show poorer results as compared to spontaneous conception. Aims: To evaluate the outcome of multifetal pregnancies and to compare maternal and neonatal complications between spontaneously conceived and assisted reproductive therapy. Settings and Design : Prospective case-control study. Materials and Methods :In this prospective case-control study of 2-year duration, obstetric and perinatal outcomes were compared in 36 ART twin pregnancies (Group A with 138 twins who conceived naturally (Group B. The outcomes were analyzed and used for a comparison between spontaneous and assisted multifetal pregnancies. Statistical Analysis : The continuous variables were analyzed by Student′s t -test and categorical variables were analyzed with Fisher′s exact test. Results : Pregnancy-related complications like pregnancy-induced hypertension, antepartum hemorrhage, were similar in both groups. Incidence of cesarean section, preterm delivery, and hospital stay was significantly more in Group A vs. Group B, P < 0.001. The newborns in the assisted group had more complications than the spontaneous group; most notable were respiratory distress syndrome, newborn intensive care admission, sepsis, and longer hospital stay (4.8 days vs. 1.6 days, P < 0.001. Conclusions : Increased rates of cesarean section and preterm delivery are the main reasons for increased obstetric risk in pregnancies conceived through ART. Preterm birth and neonatal prematurity-related complications were the main cause for longer stay in hospital in ART-conceived twins.

  3. Clinical signs, histopathology and genetics of experimental transmission of BSE and natural scrapie to sheep and goats.

    Science.gov (United States)

    Foster, J D; Parnham, D; Chong, A; Goldmann, W; Hunter, N

    2001-02-10

    This paper compares the dinical signs, histopathology, detection of PrPSc protein and PrP genetics of the transmission of BSE to sheep and goats, with the effects of the transmission of natural scrapie from a brain homogenate from a single sheep. After intracerebral and oral inoculations there were similarities in the clinical signs due to the two sources of infection, but there were differences in pathology at the end stage of disease and in the genotypes of the sheep which succumbed to the challenges. The incubation period of BSE was associated with the sheep PrP codon 171 genotype, but the natural scrapie source, despite inducing disease only in known susceptible genotypes, showed no clear association with PrP genotype.

  4. A Tale of Two Twin Higgses: Addressing Little Hierarchy in Natural 2HDM Framework

    CERN Document Server

    Yu, Jiang-Hao

    2016-01-01

    In original twin Higgs model, vacuum misalignment between electroweak and new physics scales is realized by adding explicit $\\mathbb{Z}_2$ breaking term. Introducing additional twin Higgs could accommodate spontaneous $\\mathbb{Z}_2$ breaking, which explains the origin of this misalignment. We introduce a class of two twin Higgs doublet models with most general scalar potential, and discuss general conditions which trigger electroweak and $\\mathbb{Z}_2$ symmetry breaking. Various scenarios on realising the vacuum misalignment are systematically discussed in a natural two Higgs double model framework: explicit $\\mathbb{Z}_2$ breaking, radiative $\\mathbb{Z}_2$ breaking, tadpole-induced $\\mathbb{Z}_2$ breaking, and quartic-induced $\\mathbb{Z}_2$ breaking. We investigate the Higgs mass spectra and the Higgs phenomenology in these scenarios.

  5. Mechanical twinning in small quartz crystals

    Science.gov (United States)

    Laughner, J. W.; Newnham, R. E.; Cross, L. E.

    1982-02-01

    Quartz is known to be ferrobielastic; that is, quartz crystals have domain states (Dauphiné twins) which differ in their elastic compliance values and which can be switched by an appropriately oriented stress. Polycrystalline quartz has also been reported (Tullis 1970) to show preferential orientation of these domains following application of large uniaxial stresses. These experiments were designed to study twinning of synthetic quartz “grains” (minimum size 0.07×0.07×0.02 cm) in specially-constructed composites and of grains in three natural quartz aggregates — a quartzite, a novaculite, and a jasper. Backreflection X-ray techniques were used to verify twinning in the composite grains, while special electroding and electrical detection allowed the twinning processes to be examined in “real time.” Small synthetic quartz crystals were found to behave identically to the massive samples previously studied. Electrical pulses due to the reversal of piezoelectric coefficient d 11 in twinned quartz were detected from quartzite and from the man-made composites. Novaculite also gave electrical pulses which were probably from twinning (evidenced by the correlation of expected and observed pulse sizes and shapes), while no pulses from the jaspers indicative of twinning were detected. Grain size distribution differences are considered the main structural reason for the different behaviors.

  6. On the twinning in ZnPd.

    Science.gov (United States)

    Ivarsson, Dennis C A; Burkhardt, Ulrich; Heggen, Marc; Ormeci, Alim; Armbrüster, Marc

    2017-02-22

    The intermetallic compound ZnPd has demonstrated excellent catalytic properties in methanol steam reforming. While it is known that defects and microstructures influence the catalytic properties, little is known about the defects occurring in ZnPd. Due to recent advances in synthetic methods, coarse-grained ZnPd samples are accessible. This enables the detection and investigation of twinning in ZnPd by studying the twinned regions from the macroscopic scale by polarised light and electron backscattering diffraction (EBSD) down to the atomic scale by high-resolution transmission electron microscopy (HR-TEM). Twinning occurs in {101} and is coupled with a change in the c/a ratio in the vicinity of the twin boundary. Quantum chemical calculations result in only very small energy differences between the ideal and the twinned structure, explaining the experimentally observed thermal stability of the latter. The chemical bonding was investigated by the electron localizability indicator (ELI) and compared to the one in the ideal structure. The results confirm twinning along the {101} plane and demonstrate the high stability of the twin boundaries after formation.

  7. Twin and Triplet Drugs in Opioid Research

    Science.gov (United States)

    Fujii, Hideaki

    Twin and triplet drugs are defined as compounds that contain respectively two and three pharmacophore components exerting pharmacological effects in a molecule. The twin drug bearing the same pharmacophores is a "symmetrical twin drug", whereas that possessing different pharmacophores is a "nonsymmetrical twin drug." In general, the symmetrical twin drug is expected to produce more potent and/or selective pharmacological effects, whereas the nonsymmetrical twin drug is anticipated to show both pharmacological activities stemming from the individual pharmacophores (dual action). On the other hand, nonsymmetrical triplet drugs, which have two of the same pharmacophores and one different moiety, are expected to elicit both increased pharmacological action and dual action. The two identical portions could bind the same receptor sites simultaneously while the third portion could bind a different receptor site or enzyme. This review will mainly focus on the twin and triplet drugs with an evaluation of their in vivo pharmacological effects, and will also include a description of their pharmacology and synthesis.

  8. Persistence of the protective immunity and kinetics of the isotype specific antibody response against the viral nucleocapsid protein after experimental Schmallenberg virus infection of sheep

    OpenAIRE

    Poskin, Antoine; Verite, Stephanie; Comtet, Loic; Van der Stede, Yves; Cay, Brigitte; De Regge, Nick

    2015-01-01

    International audience; AbstractSchmallenberg virus (SBV) is an Orthobunyavirus that induces abortion, stillbirths and congenital malformations in ruminants. SBV infection induces a long lasting seroconversion under natural conditions. The persistence of the protective immunity and the isotype specific antibody response upon SBV infection of sheep has however not been studied in detail. Five sheep were kept in BSL3 facilities for more than 16 months and subjected to repeated SBV infections. B...

  9. Teaching about twins: college courses and public lectures.

    Science.gov (United States)

    Segal, Nancy L

    2013-12-01

    The present article describes teaching experiences and observations in college courses and public lectures on twins. It is concluded that much more information about twins, at both research and practical levels, requires general dissemination. This discussion is followed by reviews of recent twin research on the topics of obesity control, post-zygotic mutation, in vitro fertilization, and schisis-associated defects. Media reports of twins accused of rape, infant Chinese twins sold separately for profit, a twin CEO, and twins pursuing the same career are presented.

  10. Acardiac Parabiotic Fetus: A Rare Complication of Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Sood S

    2015-10-01

    Full Text Available Acardiac parabiotic fetus is sequelae of complication of monochorionic monoamniotic twin pregnancy also known as Twin Reversed Arterial Perfusion Sequence (TRAP. It is rare affecting 1 in 35,000 births and 1 % of monozygotic twins. Acardiac parabiotic twin commonly known as parasite occurs rarely and may lead to high output cardiac failure, hydrops or premature delivery in the pump fetus. In this report, we present a 23 years old primigravida with twin pregnancy, with twin reversed arterial perfusion sequence with one of the twins being acardiac anceps and the other normal pump fetus. This association is relatively uncommon and therefore rarely documented.

  11. Bighorn sheep × domestic sheep hybrids survive Mannheimia haemolytica challenge in the absence of vaccination.

    Science.gov (United States)

    Subramaniam, R; Shanthalingam, S; Bavananthasivam, J; Kugadas, A; Raghavan, B; Batra, S A; Herndon, C N; Rodriguez, J; Tibary, A; Nelson, D; Potter, K A; Foreyt, W J; Srikumaran, S

    2014-06-04

    Bighorn sheep (BHS, Ovis canadensis) are much more susceptible than domestic sheep (DS, Ovis aries) to pneumonia caused by leukotoxin (Lkt)-producing members of the Family Pasteurellaceae, particularly Mannheimia haemolytica and Bibersteinia trehalosi. Leukotoxin is widely accepted as the critical virulence factor of these bacteria since Lkt-negative mutants do not cause death of BHS. Typically, DS carry Lkt-positive M. haemolytica and/or B. trehalosi as commensal bacteria in their nasopharynx. In contrast, most BHS do not carry Lkt-positive M. haemolytica or B. trehalosi, or carry Lkt-negative strains in their nasopharynx. In previous studies, we demonstrated that unimmunized DS resist M. haemolytica challenge while BHS succumb to it. We hypothesized that Lkt-neutralizing antibodies, induced by Lkt-positive M. haemolytica and/or B. trehalosi innately carried by DS in their nasopharynx, render them less susceptible to infection by these bacteria. In this study we developed BHS×DS F1 hybrids by artificial insemination of domestic ewes with BHS semen. F1 hybrids were fertile, and produced F2 hybrids and back-crosses. The F1, F2, and back-crosses were raised together with domestic ewes. All these animals acquired Lkt-positive M. haemolytica and/or B. trehalosi, and developed high titers of Lkt-neutralizing antibodies in the absence of vaccination. Furthermore, all of these animals resisted challenge with lethal dose of M. haemolytica. These results suggest that lack of previous exposure to Lkt is at least partially responsible for fatal pneumonia in BHS when they acquire Lkt-positive M. haemolytica and/or B. trehalosi from DS when the two species commingle. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Immune Response Evaluation in Sheep Infected with Larvae of Wohlfahrtia Magnifica

    Directory of Open Access Journals (Sweden)

    Daniela Marina Mot

    2013-05-01

    Full Text Available The sheep myiasis is a seriously debilitating disease that has the potential to generate a substantial stress to affected animals. All lesions severity and animals state of health can be retrieved in immunological parameters detection, because always results an immune response to challenge factors which intercede in their productive life. Today is important to find non-chemical methods of ectoparasites control, from natural resistance or vaccine induced resistance. The study was carried out to infected and uninfected sheep with larvae of Wohlfahrtia magnifica. From two groups of healthy and parasited sheep were been taken blood samples. From the group from sheep with myiasis were been detected the cutaneous lesions with W. magnifica maggots and these maggots were been collected. The mechanisms of unspecific immune defending were been studied through cellular effectors by leucogram. In leucogram appear quantitative differences between different categories of cells which take part in immune response, such as polymorphonuclears (neutrophiles, eozinophiles and mononuclears (limphocytes.  The immune specific answer were been detected through radial simple immunodiffusion test made with antigen prepared from W. magnifica maggots from the third stage of development, in the view of estimating the presence of an immune reaction through antibodies synthesis in infested sheep. In both studies were been detected immune responses of parasite hosts. All immunological studies may allow a sustainable ectoparasites control utilizing host resistance which seems to be attainable in the near future.

  13. Osteoporotic Characteristics Persist in the Spine of Ovariectomized Sheep after Withdrawal of Corticosteroid Administration

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Zarrinkalam

    2012-01-01

    Full Text Available A validated ovine model of osteoporosis achieves severe bone loss in a relatively short period. This study investigated if osteoporotic features persist in this model after cessation of corticosteroid administration. Methods. Osteoporosis was induced in nine ewes by chronic corticosteroid injection, ovariectomy, and low calcium diet. Six ewes were used as controls. Bone mineral density (BMD of the lumbar spine (LS and body weight were assessed at regular intervals. After five months, corticosteroid treatment was withdrawn systematically over one month. Three months later, all animals were euthanised, and the LS was collected for histomorphometric analysis. Results. BMD in the LS of osteoporotic sheep was 25% lower than control sheep. Body weight of osteoporotic sheep was reduced in the first month of the corticosteroid withdrawal period but returned to baseline level thereafter. Trabecular bone volume of LS in osteoporotic sheep was 27% lower than controls and showed a heterogeneous structure. Conclusions. Osteoporotic characteristics remain in the vertebra after ceasing corticosteroid administration providing an opportunity to evaluate potential systemic or local treatments in vivo under realistic physiological conditions. The microstructural arrangement of vertebral trabecular bone in sheep is similar to humans demonstrating further relevance of this model for preclinical investigations.

  14. Osteoporotic characteristics persist in the spine of ovariectomized sheep after withdrawal of corticosteroid administration.

    Science.gov (United States)

    Zarrinkalam, Mohammad-Reza; Schultz, Christopher G; Parkinson, Ian H; Moore, Robert J

    2012-01-01

    A validated ovine model of osteoporosis achieves severe bone loss in a relatively short period. This study investigated if osteoporotic features persist in this model after cessation of corticosteroid administration. Methods. Osteoporosis was induced in nine ewes by chronic corticosteroid injection, ovariectomy, and low calcium diet. Six ewes were used as controls. Bone mineral density (BMD) of the lumbar spine (LS) and body weight were assessed at regular intervals. After five months, corticosteroid treatment was withdrawn systematically over one month. Three months later, all animals were euthanised, and the LS was collected for histomorphometric analysis. Results. BMD in the LS of osteoporotic sheep was 25% lower than control sheep. Body weight of osteoporotic sheep was reduced in the first month of the corticosteroid withdrawal period but returned to baseline level thereafter. Trabecular bone volume of LS in osteoporotic sheep was 27% lower than controls and showed a heterogeneous structure. Conclusions. Osteoporotic characteristics remain in the vertebra after ceasing corticosteroid administration providing an opportunity to evaluate potential systemic or local treatments in vivo under realistic physiological conditions. The microstructural arrangement of vertebral trabecular bone in sheep is similar to humans demonstrating further relevance of this model for preclinical investigations.

  15. Pharmacokinetics of fenbendazole in sheep.

    Science.gov (United States)

    Marriner, S E; Bogan, J A

    1981-07-01

    Concentrations of fenbendazole and its sulfoxide, oxfendazole, and sulfone metabolites were determined in 6 sheep after oral administration of fenbendazole (10 mg/kd of body weight). Mean peak concentrations in plasma of fenbendazole, oxfendazole, and sulfone of 0.15, 0.29, and 0.17 micrograms/ml occurred 24, 30, and 36 hours after administration, respectively. Mean peak concentrations in abomasal fluid were 1.82, 0.66, and 0.07 micrograms/ml occurring at 30, 48, and 72 hours, respectively. Fenbendazole and oxfendhzole were detectable in plasma and abomasal fluids for 5 days after administration. Much of the anthelmintic activity of fenbendazole may be due to the oxfendazole metabolite. Plasma concentrations of fenbendazole were less and persisted for a shorter period after intra-abomasal administration than after oral administration.

  16. Maternal transmission studies of BSE in sheep.

    Science.gov (United States)

    Foster, J D; Goldmann, W; McKenzie, C; Smith, A; Parnham, D W; Hunter, N

    2004-10-01

    If BSE (bovine spongiform encephalopathy) infected the UK sheep population concurrently with cattle, it would only now be maintained by transmission between sheep by routes which could include from mother to lamb either in utero or via perinatal close contact. In this study of experimental BSE, Cheviot ewes challenged orally with BSE cattle brain produced lambs of various PrP genotypes over the next 7 years. Of 72 surviving to >30 months of age, 29 are of the most susceptible PrP genotype (AQ/AQ) and born to mothers that were challenged with BSE. None of the progeny have shown any signs of disease. The results suggest that in these sheep, BSE could only transmit by the maternal route at a frequency of less than one in four (95 % confidence limit) from clinically affected ewes, a rate which if replicated in other breeds may not be sufficient to maintain BSE within the sheep population.

  17. Selective breeding for scrapie resistance in sheep

    Directory of Open Access Journals (Sweden)

    Cristina Santos Sotomaior

    2012-11-01

    Full Text Available It is well known that the susceptibility of sheep to scrapie is determined by the host’s prion protein gene (PRNP. PRNP polymorphisms at codons 136 (alanine, A/valine, V, 154 (histidine, H/arginine, R and 171 (glutamine, Q/histidine, H/arginine, R are the main determinants of sheep susceptibility/resistance to classical scrapie. There are four major variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programs have been developed in the European Union and the USA to increase the frequency of the resistant ARR allele while decreasing the frequency of the susceptible VRQ allele in sheep populations. In Brazil, little PRNP genotyping data are available for sheep, and thus far, no controlled breeding scheme for scrapie has been implemented. This review will focus on important epidemiological aspects of scrapie and the use of genetic resistance as a tool in breeding programs to control the disease.

  18. Familial aggregation of atrial fibrillation: a study in Danish twins

    DEFF Research Database (Denmark)

    Christophersen, Ingrid Elisabeth; Ravn, Lasse Steen; Budtz-Joergensen, Esben

    2009-01-01

    BACKGROUND: Heritability may play a role in nonfamilial atrial fibrillation (AF). We hypothesized that a monozygotic (MZ) twin whose co-twin was diagnosed with AF would have an increased risk of the disease compared with a dizygotic (DZ) twin in the same situation. METHODS AND RESULTS: A sample...... of 1137 same-sex twin pairs (356 MZ and 781 DZ pairs) in which one or both members were diagnosed with AF were identified in The Danish Twin Registry. Concordance rates were twice as high for MZ pairs than for DZ pairs regardless of sex (22.0% versus 11.6%, P...-free survival times, we compared the time span between occurrences of disease in MZ and DZ twins. The unaffected twin was included when his or her twin-sibling (the index twin) was diagnosed with AF. After adjustment for age at entry, MZ twins had a significantly shorter event-free survival time (hazard ratio...

  19. Immunohistochemical and histopathological findings of ovine pulmonary adenocarcinoma (Jaagsiekte) in Egyptian sheep.

    Science.gov (United States)

    Oda, Samah Shehata; Youssef, Sameh Ahmed

    2011-12-01

    Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring retrovirus-induced transmissible lung cancer in sheep. Lungs and associated (bronchial and mediastinal) lymph nodes of seven sheep with OPA were examined. Lungs had few multifocal consolidated slightly elevated gray to white masses ranging from 0.5 to 3 cm in diameter. Histopathologically, these masses appeared as well-differentiated acinar adenocarcinoma with little evidence of anaplasia. The acini composed of well-differentiated cuboidal to low columnar epithelium with clear or vacuolated cytoplasm and low mitotic index. No metastases were observed in the bronchial and mediastinal lymph nodes of any animal. The presence of Jaagsiekte sheep retrovirus (JSRV) was demonstrated in the lungs by immunohistochemistry. JSRV protein was detected in all tumor epithelial cells, histologically normal alveolar type II cells, and few bronchiolar epithelial cells, alveolar macrophages, lymphocytes, and plasma cells. This study is the first to confirm the presence of natural OPA in Egypt.

  20. Effects of gossypol from cottonseed cake on the blood profile in sheep.

    Science.gov (United States)

    Câmara, Antônio Carlos Lopes; do Vale, André Menezes; Mattoso, Cláudio Roberto Scabelo; Melo, Marília Martins; Soto-Blanco, Benito

    2016-06-01

    Cottonseed cake contains gossypol, a potentially toxic compound that, when consumed by sheep, can affect reproduction, the immune system, and the liver. Changes in hematologic and serum biochemical parameters were monitored for 63 days in 12 Santa Inês ewes, six of which received ration containing 400 g kg(-1) of cottonseed cake. Blood samples were collected at the start of the experiment and weekly thereafter for hematologic assessment and determination of serum urea, creatinine, total protein, and albumin concentrations and for measurement of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transferase activities. No clinical signs of toxicity were observed. Evaluation of the erythron showed that sheep consuming cottonseed cake had an increased packed cell volume (p cake by sheep for 63 days may induce changes in the erythron but no consistent changes in serum biochemical parameters, indicating no damage to the liver or kidneys.

  1. A comparative study of sheep and pigs given the tremorgenic mycotoxins verruculogen and penitrem A.

    Science.gov (United States)

    Peterson, D W; Penny, R H; Day, J B; Mantle, P G

    1982-09-01

    The moulds Penicillium simplicissimum and P crustosum and the tremorgenic mycotoxins, verruculogen and penitrem A, isolated from them, were given to sheep and pigs to compare their potencies. Pigs were generally less susceptible and in both species penitrem A was less potent than verruculogen. Five-month-old lambs seemed more susceptible to mycelium containing verruculogen than were 15-month-old sheep given a similar oral dose relative to bodyweight. Repeated daily dosing of lambs and sheep for five days with P simplicissimum failed to enhance the effect, indicating that verruculogen toxicity was not cumulative. Long and short acting barbiturate anaesthesia blocked the effects of lethal doses of tremorgens. Sedation with diazepam diminished, but did not block, mycotoxin-induced tremors suggesting that there was no specific action of this anticonvulsant sedative on tremorgens.

  2. Unequal but monozygous: a history of twin-twin transfusion syndrome.

    Science.gov (United States)

    Obladen, Michael

    2010-03-01

    Twin-twin transfusion is the major cause of mortality and morbidity in monochorionic twins. Its pathogenesis has been gradually elucidated over the last three centuries. Among obstetricians, there was a long-lasting controversy on the existence of placental anastomoses and whether or not to tie the placental end of the firstborn infant's cord. However, a twin pregnancy practically never could be excluded. Stalpart van der Wiel described a twin-twin vessel connection in 1687. Studies on interfetal anastomoses using injection of placental vessels were published by Smellie in 1752, Osiander in 1781, and Brachet in 1821. Different types of anastomoses, and their associated fetal disorders were classified by Schatz in a series of papers at the end of the 19(th) century. With the advent of ultrasound and laser techniques, prenatal diagnosis and treatment became available in the last decade of the 20(th) century.

  3. The Vanishing Twin Syndrome: Two Cases of Extreme Malformations Associated With Vanished Twins.

    Science.gov (United States)

    Shinnick, Julia K; Khoshnam, Nasim; Archer, Sydney R; Quigley, Philip C; Robinson, Haynes; Keene, Sarah; Santore, Matthew T; Hill, Sarah; Patel, Binita; Shehata, Bahig M

    2017-01-01

    Two cases of devastating fetal malformations associated with vanished monochorionic twins were identified upon review of pathology files. A 35-year-old G1P0 woman and 36-year-old G3P1 woman were both diagnosed with an intrauterine twin gestation via transvaginal ultrasound at 10 weeks. The spectrum of fetal anomalies ranged from omphalocele, bilateral upper extremity, and unilateral lower extremity hypoplasia, to craniofacial malformation with diaphragmatic hernia. On histopathologic examination, the placentas demonstrated vascular anastomoses between the surviving co-twin and the "vanished" fetal sac. We propose anastomotic placental vasculature as a contributing factor to the observed fetal malformations. Additionally, genetic or teratogenic factors may have been attributed to the demise of the first twin and the anomalies seen in the other twin. While such instances are rare, they are important to consider when counseling patients regarding outcomes associated with a monochorionic vanished twin.

  4. Twin trisomies-Edward and Patau syndromes.

    Science.gov (United States)

    Massiah, Nadine; Griffiths, Emma; Bamigboye, Vincent

    2008-11-01

    To report the rare occurrence of dichorionic diamniotic twins with dissimilar aneuploidies. Case report. District general hospital. A 36-year-old woman conceived by in vitro fertilization. Dichorionic diamniotic twins were found to have elevated nuchal translucencies and cystic hygromas. Intrauterine deaths occurred at 13 and 17 weeks gestation. Medical termination of pregnancy. Karyotypes. Cytogenetic studies confirmed Edward's and Patau's syndromes. The aetiology is unknown but maternal age and in vitro fertilization may be linked since the incidence of aneuploidy rises with maternal age and the incidence of twins' increases with assisted reproductive techniques. This case highlights the need for obstetricians to have good communication and counselling skills.

  5. Undiagnosed xiphopagus twins: a perinatal malady

    Directory of Open Access Journals (Sweden)

    Gowri Dorairajan

    2012-02-01

    Full Text Available Conjoined twins are a very rare entity. It is associated with poor survival rate in the presence of vital organ sharing. The entity can be diagnosed as early as the first trimester. A conjoined twin diagnosed late in labor is a malady with high perinatal mortality and maternal morbidity. We present one such case of xiphopagus twins. The management of a case diagnosed late in labor can be very challenging. Such obstetric challenges can be avoided by a meticulous early scan with a high index of suspicion, especially in the absence of separating membrane while scanning multiple pregnancies.

  6. New growth mode through decorated twin boundaries.

    Science.gov (United States)

    Bleikamp, Sebastian; Thoma, Arne; Polop, Celia; Pirug, Gerhard; Linke, Udo; Michely, Thomas

    2006-03-24

    Scanning tunneling microscopy and low energy electron diffraction were used to investigate the growth of partly twinned Ir thin films on Ir(111). A transition from the expected layer-by-layer to a defect dominated growth mode with a fixed lateral length scale and increasing roughness is observed. During growth, the majority of the film is stably transformed to twinned stacking. This transition is initiated by the energetic avoidance of the formation of intrinsic stacking faults compared to two independent twin faults. The atomistic details of the defect kinetics are outlined.

  7. Intravenous nutrition during a twin pregnancy.

    Science.gov (United States)

    Karamatsu, J T; Boyd, A T; Cooke, J; Vinall, P S; McMahon, M J

    1987-01-01

    A case is reported of a woman in the third trimester of a twin pregnancy who required intravenous nutrition because of inadequate absorption of nutrients due to a jejunoileal bypass. Weight gain was poor, and there was evidence of intrauterine growth retardation before commencement of intravenous feeding. She received overnight intravenous nutrition for 6 weeks and gained weight with ultrasound evidence of fetal growth. During the 33rd week of gestation, she was delivered of healthy twin males who were at appropriate birth weights and development for their age of gestation. The considerations in intravenous nutrition for a twin pregnancy after jejunoileal bypass are discussed.

  8. Nanoscale growth twins in sputtered metal films

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Amit [Los Alamos National Laboratory; Anderoglu, Osman [Los Alamos National Laboratory; Hoagland, Richard G [Los Alamos National Laboratory; Zhang, X [TEXAS A& M

    2008-01-01

    We review recent studies on the mechanical properties of sputtered Cu and 330 stainless steel films with {l_brace}1 1 1{r_brace} nanoscale growth twins preferentially oriented perpendicular to growth direction. The mechanisms of formation of growth twins during sputtering and the deformation mechanisms that enable usually high strengths in nanotwinned structures are highlighted. Growth twins in sputtered films possess good thermal stability at elevated temperature, providing an approach to extend the application of high strength nanostructured metals to higher temperatures.

  9. TwinFocus CPV system

    Science.gov (United States)

    Nardello, Marco; Centro, Sandro

    2017-09-01

    TwinFocus® is a CPV solution that adopts quasi-parabolic, off axis mirrors, to obtain a concentration of 760× on 3J solar cells (Azur space technology) with 44% efficiency. The adoption of this optical solution allows for a cheap, lightweight and space efficient system. In particular, the addition of a secondary optics to the mirror, grants an efficient use of space, with very low thicknesses and a compact modular design. Materials are recyclable and allow for reduction of weights to a minimum level. The product is realized through the cooperation of leading edge industries active in automotive lighting and plastic materials molding. The produced prototypes provide up to 27.6% efficiency according to tests operated on the field with non-optimal spectral conditions.

  10. Cohort Profile : The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry)

    NARCIS (Netherlands)

    Gatz, Margaret; Harris, Jennifer R.; Kaprio, Jaakko; McGue, Matt; Smith, Nicholas L.; Snieder, Harold; Spiro, Avron; Butler, David A.

    2015-01-01

    The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry) is a comprehensive registry of White male twin pairs born in the USA between 1917 and 1927, both of the twins having served in the military. The purpose was medical research and ultimately improved clini

  11. Technological suitability of sheep milk for processing

    Directory of Open Access Journals (Sweden)

    Romualda Danków

    2011-06-01

    Full Text Available Annual world sheep milk production is estimated at the level of 8.2 million tons and constitutes 1.5% of the total milk production obtained from various species of mammals. Majority of this milk is used to manufacture cheeses and fermented beverages. These products are commonly considered as regional articles and are protected by legal regulations which guarantee their taste and aroma typical for a given region and which they owe to traditional production technologies. In Poland, sheep are reared, primarily, in mountainous areas (Podhale, Bieszczady but also in Wielkopolska and Podlasie. The sheep population in Poland is estimated at 223 000 animals but milk is obtained only from a small number of animals and its annual production is assessed at the level of 1000 t. The nutritional value of sheep milk is higher in comparison with goat or cow milk. Sheep milk protein is characterised by a high biological value comparable with the biological value of the whole chicken egg. In addition, products manufactured from sheep milk possess high nutritive value. Due to its rich chemical composition, sheep milk provides an excellent raw material for processing into maturing soft and hard cheeses (75-80% of protein is casein, for fermented beverages, both natural and with different tastes, as well as butter, ghee and ice-cream. High proportion of dry matter (up to 18% found in sheep milk does not require application of any thickeners in production of fermented beverages. That is why these beverages are fully natural and free of additives.

  12. Technological suitability of sheep milk for processing

    OpenAIRE

    Romualda Danków; Jan Pikul

    2011-01-01

    Annual world sheep milk production is estimated at the level of 8.2 million tons and constitutes 1.5% of the total milk production obtained from various species of mammals. Majority of this milk is used to manufacture cheeses and fermented beverages. These products are commonly considered as regional articles and are protected by legal regulations which guarantee their taste and aroma typical for a given region and which they owe to traditional production technologies. In Poland, sheep are re...

  13. Myocardial hypertrophy in the recipient with twin-to-twin transfusion syndrome

    DEFF Research Database (Denmark)

    Jeppesen, D.L.; Jorgensen, F.S.; Pryds, O.A.

    2008-01-01

    In a set of monochorionic-diamniotic twins with twin-to-twin transfusion syndrome, systemic hypertension and biventricular myocardial hypertrophy were found in the recipient. The infant developed mild respiratory distress. A partial exchange transfusion was performed because of polycytaemia. Blood...... pressure measurements revealed persistent systemic hypertension. Biventricular hypertrophy was demonstrated by echocardiography. Blood pressure normalised after treatment with Nifedipine and the cardiac hypertrophy subsided over the following weeks. A potential contributing mechanism is intrauterine...

  14. Parasitic twin with gastroschisis is one of the rarest variant of conjoined twins: a case report.

    Science.gov (United States)

    Baskaran, D; Aleem, M A; Ravi, R

    2015-04-01

    We report a case of parasitic twin or incomplete or heteropagus twining of extra portions of a pelvis, lower and upper limbs, duplication of genitalia and herniation of intestinal tract with spleen-variant of conjoined twinning (CT) consistent with fusion of two embryos followed by resorption of the caudal half of one of them, resulting in a normal male baby with the upper half of a male parasitic twin fused to his chest.

  15. Myocardial hypertrophy in the recipient with twin-to-twin transfusion syndrome

    DEFF Research Database (Denmark)

    Jeppesen, D.L.; Jorgensen, F.S.; Pryds, O.A.

    2008-01-01

    pressure measurements revealed persistent systemic hypertension. Biventricular hypertrophy was demonstrated by echocardiography. Blood pressure normalised after treatment with Nifedipine and the cardiac hypertrophy subsided over the following weeks. A potential contributing mechanism is intrauterine......In a set of monochorionic-diamniotic twins with twin-to-twin transfusion syndrome, systemic hypertension and biventricular myocardial hypertrophy were found in the recipient. The infant developed mild respiratory distress. A partial exchange transfusion was performed because of polycytaemia. Blood...

  16. Sudanese live sheep and mutton exports competitiveness

    Directory of Open Access Journals (Sweden)

    Babiker Idris Babiker

    2011-01-01

    Full Text Available The livestock sector of Sudan provides livelihood for about 17% of the population. Sudanese livestock products meet the domestic demand for meat in addition to a substantial excess for export amounting to about 22% of total country exports. It contributes about 19% of GDP. Sheep marketing in Sudan is characterised by traditional operations and is informally organised, although, recently there are great efforts by the formal livestock authorities to organise some secondary and terminal livestock markets. These markets are deficient in basic infrastructures and systematic marketing research. The system as a whole is faced by various complex obstacles and constraints, which decrease the contribution of livestock in general, and sheep in particular, to the national economy, and suppress the optimum exploitation of this resource. These obstacles are represented in the lack of transportation networks that connect the production and consumption centres to break the seasonality of supply that creates shortages and high prices at the consumption centres. This paper employs the policy analysis matrix (PAM technique to examine the Sudanese live sheep and mutton competitiveness in the international market. The results indicated that the market price was greater than the border price implying a positive incentive as an implicit subsidy to the live sheep exporter. The mutton exporters were found subsidised as well. The international value added (IVA indicted a positive foreign exchange earnings or savings. Exported live sheep and mutton coefficient of competitiveness (CIC implied that sheep and mutton exports are profitable and internationally competitive.

  17. Spatio-temporal dynamics of pneumonia in bighorn sheep

    Science.gov (United States)

    Cassirer, E. Frances; Plowright, Raina K.; Manlove, Kezia R.; Cross, Paul C.; Dobson, Andrew P.; Potter, Kathleen A.; Hudson, Peter J.

    2013-01-01

    Bighorn sheep mortality related to pneumonia is a primary factor limiting population recovery across western North America, but management has been constrained by an incomplete understanding of the disease. We analysed patterns of pneumonia-caused mortality over 14 years in 16 interconnected bighorn sheep populations to gain insights into underlying disease processes. 2. We observed four age-structured classes of annual pneumonia mortality patterns: all-age, lamb-only, secondary all-age and adult-only. Although there was considerable variability within classes, overall they differed in persistence within and impact on populations. Years with pneumonia-induced mortality occurring simultaneously across age classes (i.e. all-age) appeared to be a consequence of pathogen invasion into a naïve population and resulted in immediate population declines. Subsequently, low recruitment due to frequent high mortality outbreaks in lambs, probably due to association with chronically infected ewes, posed a significant obstacle to population recovery. Secondary all-age events occurred in previously exposed populations when outbreaks in lambs were followed by lower rates of pneumonia-induced mortality in adults. Infrequent pneumonia events restricted to adults were usually of short duration with low mortality. 3. Acute pneumonia-induced mortality in adults was concentrated in fall and early winter around the breeding season when rams are more mobile and the sexes commingle. In contrast, mortality restricted to lambs peaked in summer when ewes and lambs were concentrated in nursery groups. 4. We detected weak synchrony in adult pneumonia between adjacent populations, but found no evidence for landscape-scale extrinsic variables as drivers of disease. 5. We demonstrate that there was a >60% probability of a disease event each year following pneumonia invasion into bighorn sheep populations. Healthy years also occurred periodically, and understanding the factors driving these

  18. Spatio-temporal dynamics of pneumonia in bighorn sheep.

    Science.gov (United States)

    Cassirer, E Frances; Plowright, Raina K; Manlove, Kezia R; Cross, Paul C; Dobson, Andrew P; Potter, Kathleen A; Hudson, Peter J

    2013-05-01

    1. Bighorn sheep mortality related to pneumonia is a primary factor limiting population recovery across western North America, but management has been constrained by an incomplete understanding of the disease. We analysed patterns of pneumonia-caused mortality over 14 years in 16 interconnected bighorn sheep populations to gain insights into underlying disease processes. 2. We observed four age-structured classes of annual pneumonia mortality patterns: all-age, lamb-only, secondary all-age and adult-only. Although there was considerable variability within classes, overall they differed in persistence within and impact on populations. Years with pneumonia-induced mortality occurring simultaneously across age classes (i.e. all-age) appeared to be a consequence of pathogen invasion into a naïve population and resulted in immediate population declines. Subsequently, low recruitment due to frequent high mortality outbreaks in lambs, probably due to association with chronically infected ewes, posed a significant obstacle to population recovery. Secondary all-age events occurred in previously exposed populations when outbreaks in lambs were followed by lower rates of pneumonia-induced mortality in adults. Infrequent pneumonia events restricted to adults were usually of short duration with low mortality. 3. Acute pneumonia-induced mortality in adults was concentrated in fall and early winter around the breeding season when rams are more mobile and the sexes commingle. In contrast, mortality restricted to lambs peaked in summer when ewes and lambs were concentrated in nursery groups. 4. We detected weak synchrony in adult pneumonia between adjacent populations, but found no evidence for landscape-scale extrinsic variables as drivers of disease. 5. We demonstrate that there was a >60% probability of a disease event each year following pneumonia invasion into bighorn sheep populations. Healthy years also occurred periodically, and understanding the factors driving these

  19. Comparison of Naturally Conceived and IVF-DZ Twins in the Netherlands Twin Registry: A Developmental Study

    Directory of Open Access Journals (Sweden)

    Catharina E. M. van Beijsterveldt

    2011-01-01

    Full Text Available In a large set of twin pairs, we compared twins born after IVF to naturally conceived twins with respect to birth characteristics, growth, attainment of motor milestones, and emotional and behavioral problems. Twin families were registered with the Netherlands Twin Register. We included 1534 dizygotic (DZ twins born after IVF, 5315 naturally conceived (NC DZ twins, and 1504 control NC DZ twins who were matched to the IVF twins based on maternal age, maternal educational level, smoking during pregnancy, gestational age, and offspring sex. Data were obtained by longitudinal surveys sent to fathers, mothers, and teachers at ages 1, 2, 3, 7, 10, and 12 years. Results showed no differences in growth, in attainment of motor milestones, and in behavioral development between IVF and matched NC twins. It can be concluded that for nearly all aspects, development in IVF and NC children is similar.

  20. Twin boundary energy and characterization of charge redistribution near the twin boundaries of cupperate superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, Mahnaz [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Khoshnevisan, Bahram, E-mail: m.mohammadi_2@grad.kashanu.ac.ir [Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Javad Hashemifar, S. [Department of Physics, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

    2014-12-15

    Highlights: • Ab initio simulation for twin boundary energy in YBCO system for the 1st time. • Study of the twin boundary energy variation versus the inserted strain. • Proportionality of twin lamella width by the inserted strain. • Local charge transfer and charge redistribution on the twin planes. • Total DOSs for the twined system at Fermi level is higher than the untwined one. • This explain the effect of twin boundaries in agreement with experimental data. - Abstract: Ab-initio calculations under general gradient approximation have been employed for the first time to find out twin boundary energy, γ, in twined YBCO systems. Despite a vast discrepancy in reported experimental values, our results show that the γ value falls in the range of 40–85 mJ/m{sup 2}. On the other hand, functional form of γ versus inserted strains shows that the mean value for the twin width lamella would tend to approach zero as the strain goes to zero. We have also investigated the local charge transfer and the modification of the electronic states of the basal and twin planes in YBCO, because the charge redistribution at interfaces can modify transport across the grains considerably and determine the applicability of high-T{sub c} superconductors in the electronic applications. The total density of electronic states at the Fermi level for the twined system is enhanced in comparison with the untwined one. Our results explain the influence of twin boundaries in superconductive properties of YBCO, in experimental situations.

  1. Removing the twin image in digital holography by segmented filtering of in-focus twin image

    OpenAIRE

    2008-01-01

    We propose and investigate a new digital method for the reduction of twin-image noise from digital Fresnel holograms. For the case of in-line Fresnel holography the unwanted twin is present as a highly corruptive noise when the object image is numerically reconstructed. We propose to firstly reconstruct the unwanted twin-image when it is in-focus and in this plane we calculate a segmentation mask that borders this in focus image. The twin-image is then segmented and removed by sim...

  2. Rate and Outcomes of Pulmonary Stenosis and Functional Pulmonary Atresia in Recipient Twins with Twin-Twin Transfusion Syndrome.

    Science.gov (United States)

    Ortiz, Javier U; Masoller, Narcís; Gómez, Olga; Bennasar, Mar; Eixarch, Elisenda; Lobmaier, Silvia M; Crispi, Fàtima; Gratacos, Eduard; Martinez, Josep María

    2017-01-01

    To evaluate the rate of pulmonary stenosis and functional pulmonary atresia (PS/PA) in recipient twins prior to fetal surgery for twin-twin transfusion syndrome (TTTS) and their pre- and postnatal outcomes. We carried out a prospective study including 260 cases of TTTS. Echocardiography was performed before laser surgery to detect the presence of PS/PA. The outcomes of recipients with and without PS/PA were compared. The need of postnatal cardiac interventions and the survival rate at 6 months of age were also evaluated. PS was observed in 16/260 (6.2%) of recipient twins and PA in 12/260 (4.6%). After fetal surgery, 10/28 (35.7%) recipients died, 9/28 (32.1%) showed in utero regression, and 9/28 (32.1%) had persistence of PS/PA. Postnatally, seven recipients underwent percutaneous balloon pulmonary valvuloplasty, one required surgical valvotomy and one palliative surgery. Pregnancies with recipient twins with PS/PA had lower survival of at least one twin (67.9 vs. 83.6%, p = 0.045) and lower overall survival (57.1 vs. 72.8%, p = 0.015) at 6 months of age. PS and PA were observed in 10.8% of recipients. Among these, about one third showed persistence of pulmonary valve pathology after delivery, which stresses the need for strict follow-up. © 2016 S. Karger AG, Basel.

  3. Assessing a soft twin tunneling numerical model using field data

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Using a five-floor building affected by the Yangtze River highway tunnels in Wuhan as the engineering background, we have constructed a free-field model and a coupled model to study the soil, lining, foundations and upper structure, and analyze the rules of movements of building foundation and ground induced by single tunnel and twin tunnel excavation with the Finite Element Analysis method. It is shown that for the coupled model, the longitudinal displacement of each foundation increases slowly when the tu...

  4. Translational neurophysiology in sheep: measuring sleep and neurological dysfunction in CLN5 Batten disease affected sheep.

    Science.gov (United States)

    Perentos, Nicholas; Martins, Amadeu Q; Watson, Thomas C; Bartsch, Ullrich; Mitchell, Nadia L; Palmer, David N; Jones, Matthew W; Morton, A Jennifer

    2015-04-01

    Creating valid mouse models of slowly progressing human neurological diseases is challenging, not least because the short lifespan of rodents confounds realistic modelling of disease time course. With their large brains and long lives, sheep offer significant advantages for translational studies of human disease. Here we used normal and CLN5 Batten disease affected sheep to demonstrate the use of the species for studying neurological function in a model of human disease. We show that electroencephalography can be used in sheep, and that longitudinal recordings spanning many months are possible. This is the first time such an electroencephalography study has been performed in sheep. We characterized sleep in sheep, quantifying characteristic vigilance states and neurophysiological hallmarks such as sleep spindles. Mild sleep abnormalities and abnormal epileptiform waveforms were found in the electroencephalographies of Batten disease affected sheep. These abnormalities resemble the epileptiform activity seen in children with Batten disease and demonstrate the translational relevance of both the technique and the model. Given that both spontaneous and engineered sheep models of human neurodegenerative diseases already exist, sheep constitute a powerful species in which longitudinal in vivo studies can be conducted. This will advance our understanding of normal brain function and improve our capacity for translational research into neurological disorders.

  5. Determinants of sheep prices in the highlands of northeastern Ethiopia: implication for sheep value chain development.

    Science.gov (United States)

    Kassa, Beneberu Teferra; Haile, Anteneh Girma; Essa, John Abdu

    2011-12-01

    In order to assess and identify the determinants of sheep price and price variation across time, a time series data were collected from four selected markets in North Shewa, Northeastern Ethiopia on weekly market day basis for a period of 2 years. Data on animal characteristics and purpose of buying were collected on a weekly basis from randomly selected 15-25 animals, and a total of 7,976 transactions were recorded. A general linear model technique was used to identify factors influencing sheep price, and the results showed that sheep price (liveweight sheep price per kilogram taken as a dependent variable) is affected by animal characteristics such as weight, sex, age, condition, season, and color. Most of the markets' purpose for which the animal was purchased did not affect significantly the price per kilogram. This may be due to the similarity of the markets in terms of buyer's purpose. The results suggest that there will be benefit from coordinated fattening, breeding, and marketing programs to take the highest advantage from the preferred animals' characteristics and selected festival markets. Finally, the study recommends for a coordinated action to enhance the benefit generated for all participant actors in the sheep value chain through raising sheep productivity, improving the capacity of sheep producers and agribusiness entrepreneurs to access and use latest knowledge and technologies; and strengthening linkages among actors in the sheep value chain.

  6. Immune response to allergens in sheep sensitized to house dust mite

    Directory of Open Access Journals (Sweden)

    Velden Joanne

    2008-10-01

    Full Text Available Abstract Background House dust mite (HDM allergens are a major cause of allergic asthma. Most studies using animal models of allergic asthma have used rodents sensitized with the 'un-natural' allergen ovalbumin. It has only recently been recognized that the use of animal models based on HDM provide a more relevant insight into the allergen-induced mechanisms that underpin human allergic disease. We have previously described a sheep model of human allergic asthma that uses Dermatophagoides pteronyssinus HDM. The present study extends our understanding of the immune effects of HDM and the allergens Der p 1 and Der p 2 in the sheep model of asthma. Methods Peripheral blood sera from non-sensitized (control sheep and sheep sensitized to HDM was collected to determine immunoglobulin (Ig reactivities to HDM, Der p 1 and Der p 2 by ELISA. Bronchoalveolar lavage (BAL fluid collected following allergen challenge was also assessed for the presence of HDM-specific antibodies. To examine the cellular immune response to HDM allergens, T cell proliferation and cutaneous responses were assessed in sensitized and control sheep. Results Strong HDM- and Der p 1-specific IgE, IgG1, IgG2 and IgA serum responses were observed in sensitized sheep, while detectable levels of HDM-specific IgG1 and IgA were seen in BAL fluid of allergen-challenged lungs. In contrast, minimal antibody reactivity was observed to Der p 2. Marked T cell proliferation and late phase cutaneous responses, accompanied by the recruitment of eosinophils, indicates the induction of a cellular and delayed-type hypersensitivity (DTH type II response by HDM and Der p 1 allergen, but not Der p 2. Conclusion This work characterizes the humoral and cellular immune effects of HDM extract and its major constituent allergens in sheep sensitized to HDM. The effects of allergen in HDM-sensitized sheep were detectable both locally and systemically, and probably mediated via enzymatic and immune actions of the

  7. Cooperative Research Twin Trawl Sweep Comparison Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Twin-Trawl Sweep Efficiency Study" was intended to compare the sweep efficiency and selectivity of the NEFSC standardized bottom trawl to that of a standardized...

  8. The Radiative Z2 Breaking Twin Higgs

    CERN Document Server

    Yu, Jiang-Hao

    2016-01-01

    In twin Higgs model, the Higgs boson mass is protected by a $Z_2$ symmetry. The $Z_2$ symmetry needs to be broken either explicitly or spontaneously to obtain misalignment between electroweak and new physics vacua. We propose a novel $Z_2$ breaking mechanism, in which the $Z_2$ is spontaneously broken by radiative corrections to the Higgs potential. Two twin Higgses with different vacua are needed, and vacuum misalignment is realized by opposite but comparable contributions from gauge and Yukawa interactions to the potential. Due to fully radiative symmetry breaking, the Higgs sector is completely determined by twin Higgs vacuum, Yukawa and gauge couplings. There are eight pseudo-Goldstone bosons: the Higgs boson, inert doublet Higgs, and three twin scalars. We show the 125 GeV Higgs mass and constraints from Higgs coupling measurements could be satisfied.

  9. Say No to Fake Twin Brothers

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China vows to fight fake products that exploit a home appliance stimulus project in rural areas Haier Co. Ltd., China’s top home appliance manufacturer, is well known for its logo depicting a pair of twin

  10. Twin Screw Mixer/Fine Grind Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 40-mm Twin-Screw Mixer/Extruder (TSE) pilot plant is a continuous, remotely operated, flexible facility that can significantly enhance safety and environmental...

  11. Cord entanglement in monoamniotic twin pregnancies

    DEFF Research Database (Denmark)

    Lyndrup, J; Schouenborg, Lars Øland

    1987-01-01

    Monoamniotic twin pregnancy involves a heavy risk of fatal umbilical cord entanglement. Two cases are reported. In the first case, both twins were found dead in the 36th week, and the monoamnionicity was recognized at birth. In the second case, the monoamnionicity was discovered during an ultraso......Monoamniotic twin pregnancy involves a heavy risk of fatal umbilical cord entanglement. Two cases are reported. In the first case, both twins were found dead in the 36th week, and the monoamnionicity was recognized at birth. In the second case, the monoamnionicity was discovered during...... an ultrasound examination, and cord entanglement was suspected in the 35th week on the basis of a non-stress test (NST) with variable decelerations. Cesarean section was performed and two healthy children were delivered....

  12. Thoracopagus conjoined twin: an unusual presentation

    Directory of Open Access Journals (Sweden)

    Rajesh Kumari

    2014-02-01

    Full Text Available Conjoined twins are among rare clinical conditions observed by obstetricians. Due to rare incidence of this condition there is general lack of knowledge among obstetricians, especially at primary care level which leads to missed diagnosis during antenatal period. The management of this condition is complex especially in cases where the diagnosis is not known before onset of labour. A 30 - year old Hindu lady was referred to us from other hospital with diagnosis of twin pregnancy and prolonged second stage of labour. Clinical examination revealed findings of ruptured uterus and foetal head of one baby and feet of second baby were outside the introitus. Emergency laparotomy was done which revealed conjoined twins. This article report clinical course of a thoracopagus conjoined twin. The relevant literature is also reviewed. [Int J Reprod Contracept Obstet Gynecol 2014; 3(1.000: 245-247

  13. Twin Cities Metro Hybrid Landcover 2000 (Raster)

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Hybrid Landcover is an attempt to clean up the University of Minnesota Remote Sensing Lab's 2000 LandSat Land Cover for the Twin Cities 7-county metropolitan...

  14. Spectroscopic study of solar twins and analogues

    CERN Document Server

    Datson, Juliet; Portinari, Laura

    2014-01-01

    Context. Many large stellar surveys have been and are still being carried out, providing huge amounts of data, for which stellar physical parameters will be derived. Solar twins and analogues provide a means to test the calibration of these stellar catalogues because the Sun is the best-studied star and provides precise fundamental parameters. Solar twins should be centred on the solar values. Aims. This spectroscopic study of solar analogues selected from the Geneva-Copenhagen Survey (GCS) at a resolution of 48,000 provides effective temperatures and metallicities for these stars. We test whether our spectroscopic parameters, as well as the previous photometric calibrations, are properly centred on the Sun. In addition, we search for more solar twins in our sample. Methods. The methods used in this work are based on literature methods for solar twin searches and on methods we developed in previous work to distinguish the metallicity-temperature degeneracies in the differential comparison of spectra of solar ...

  15. Twin studies: A unique epidemiological tool

    Directory of Open Access Journals (Sweden)

    Monalisha Sahu

    2016-01-01

    Full Text Available Twin studies are a special type of epidemiological studies designed to measure the contribution of genetics as opposed to the environment, to a given trait. Despite the facts that the classical twin studies are still being guided by assumptions made back in the 1920s and that the inherent limitation lies in the study design itself, the results suggested by earlier twin studies have often been confirmed by molecular genetic studies later. Use of twin registries and various innovative yet complex software packages such as the (SAS and their extensions (e.g., SAS PROC GENMOD and SAS PROC PHREG has increased the potential of this epidemiological tool toward contributing significantly to the field of genetics and other life sciences.

  16. Diabetes and Menopause: A Twin Challenge

    Science.gov (United States)

    ... years leading up to it — may present unique challenges if you have diabetes. But it's not necessarily ... while going through menopause can be a twin challenge. Work closely with your doctor to ease the ...

  17. Temporal ghost imaging with twin photons

    Science.gov (United States)

    Denis, Séverine; Moreau, Paul-Antoine; Devaux, Fabrice; Lantz, Eric

    2017-03-01

    We use twin photons generated by spontaneous parametric down conversion to perform temporal ghost imaging of a single time signal. The retrieval of a binary signal containing eight bits is performed with an error rate below 1%.

  18. Prevention of preterm delivery in twin pregnancy.

    Science.gov (United States)

    Rode, Line; Tabor, Ann

    2014-02-01

    The incidence of twin gestation has increased markedly over the past decades, mostly because of increased use of assisted reproductive technologies. Twin pregnancies are at increased risk of preterm delivery (i.e. birth before 37 weeks of gestation). Multiple gestations therefore account for 2-3% of all pregnancies but constitute at least 10% of cases of preterm delivery. Complications from preterm birth are not limited to the neonatal period, such as in retinopathy of prematurity, intraventricular haemorrhage, necrotising enterocolitis, respiratory disorder and sepsis; they can also constitute sequelae such as abnormal neurophysiological development in early childhood and underachievement in school. Several treatment modalities have been proposed in singleton high-risk pregnancies. The mechanism of initiating labour may, however, be different in singleton and twin gestations. Therefore, it is mandatory to evaluate the proposed treatments in randomised trials of multiple gestations. In this chapter, we describe the results of trials to prevent preterm delivery in twin pregnancies.

  19. Infantile Perineal Protrusion in Two Monochorionic Twins

    Directory of Open Access Journals (Sweden)

    Paola Cavicchioli

    2014-11-01

    Full Text Available Case Report - Two female monochorionic-monoamniotic twins showed the same kind of infantile perineal protrusion (IPP at birth. Lesions in both twins progressively healed until resolution in 6 weeks' time; none of the twins have manifested, till date, alvus disturbances. Discussion and Literature Review - A literature review numbers approximately 100 reports of IPP. This condition has been classically classified into three categories: congenital/familiar (i.e., female sex, positive parental history of IPP, acquired (mainly due to constipation, and associated with lichen sclerosus et atrophicus. Conclusions and Final Remarks - This case report describes, for the first time, the presence of IPP in monochorionic-monoamniotic twins, supporting the existence of hereditary/genetic factors in the developing of this condition.

  20. Stolen twin: fascination and curiosity/twin research reports: evolution of sleep length; dental treatment of craniopagus twins; cryopreserved double embryo transfer; gender options in multiple pregnancy/current events: appendectomy in one twin; autistic twin marathon runners; 3D facial recognition; twin biathletes.

    Science.gov (United States)

    Segal, Nancy L

    2014-02-01

    The story of her allegedly stolen twin brother in Armenia is recounted by a 'singleton twin' living in the United States. The behavioral consequences and societal implications of this loss are considered. This case is followed by twin research reports on the evolution of sleep length, dental treatment of craniopagus conjoined twins, cryopreserved double embryo transfer (DET), and gender options in multiple pregnancy. Current events include the diagnosis of appendectomy in one identical twin, the accomplishments of autistic twin marathon runners, the power of three-dimensional (3D) facial recognition, and the goals of twin biathletes heading to the 2014 Sochi Olympics in Russia.

  1. Deformation Twinning During Nanoindentation of Nanocrystalline Ta

    OpenAIRE

    Wang, Y. M.; Hodge, A. M.; Biener, J.; Hamza, A.V.; Barnes, D E; Liu, Kai; Nieh, T. G.

    2005-01-01

    The deformation mechanism of body-centered cubic (bcc) nanocrystalline tantalum with grain sizes of 10–30 nm is investigated by nanoindentation, scanning electron microscopy and high-resolution transmission electron microscopy. In a deviation from molecular dynamics simulations and existing experimental observations on other bcc nanocrystalline metals, the plastic deformation of nanocrystalline Ta during nanoindentation is controlled by deformation twinning. The observation of multiple twin i...

  2. Strong crystal size effect on deformation twinning

    DEFF Research Database (Denmark)

    Yu, Qian; Shan, Zhi-Wei; Li, Ju

    2010-01-01

    find that the stress required for deformation twinning increases drastically with decreasing sample size of a titanium alloy single crystal7, 8, until the sample size is reduced to one micrometre, below which the deformation twinning is entirely replaced by less correlated, ordinary dislocation....... The sample size in transition is relatively large and easily accessible in experiments, making our understanding of size dependence11, 12, 13, 14, 15, 16, 17 relevant for applications....

  3. The Twin Research Registry at SRI International.

    Science.gov (United States)

    Krasnow, Ruth E; Jack, Lisa M; Lessov-Schlaggar, Christina N; Bergen, Andrew W; Swan, Gary E

    2013-02-01

    The Twin Research Registry (TRR) at SRI International is a community-based registry of twins established in 1995 by advertising in local media, mainly on radio stations and in newspapers. As of August 2012, there are 3,120 same- and opposite-sex twins enrolled; 86% are 18 years of age or older (mean age 44.9 years, SD 16.9 years) and 14% less than 18 years of age (mean age 8.9 years, SD 4.5); 67% are female, and 62% are self-reported monozygotic (MZ). More than 1,375 twins have participated in studies over the last 15 years in collaboration with the University of California Medical Center in San Francisco, the University of Texas MD Anderson Cancer Center, and the Stanford University School of Medicine. Each twin completes a registration form with basic demographic information either online at the TRR Web site or during a telephone interview. Contact is maintained with members by means of annual newsletters and birthday cards. The managers of the TRR protect the confidentiality of twin data with established policies; no information is given to other researchers without prior permission from the twins; and all methods and procedures are reviewed by an Institutional Review Board. Phenotypes studied thus far include those related to nicotine metabolism, mutagen sensitivity, pain response before and after administration of an opioid, and a variety of immunological responses to environmental exposures, including second-hand smoke and vaccination for seasonal influenza virus and Varicella zoster virus. Twins in the TRR have participated in studies of complex, clinically relevant phenotypes that would not be feasible to measure in larger samples.

  4. Twin birth order, birthweight and birthweight discordance: any relationship

    Directory of Open Access Journals (Sweden)

    Onyiriuka A.N.

    2010-12-01

    Full Text Available Background: It is widely believed that in twin pairs, at birth, the first-born weigh more than the second-born but this concept has been challenged. Objective: To assess the truthfulness of this common concept that first-born twins are usually heavier than their second-born siblings at birth. Methods: In a series of 104 sets of live-born twins, the birth weights of first-born twins were compared with those of their second-born siblings, after controlling for gender. Their intra-pair birthweight differences were determined and twin pairs whose birthweight difference was 15% or more were designated as discordant. Results: Twin I was heavier than Twin II in 61.5% of cases while Twin II was heavier than Twin I in 28.9% of cases. Twins I and II had equal birthweights in 9.6% of cases. Comparing the mean birthweight of the first-born-male twin with that of second-born- male twin, it was 2515+427g (95% Confidence Interval, CI=2402-2628 versus 2432 +435g (95% CI=2321-2543 p>0.05. The mean birthweight of first-born-female twin was 2326+445g (95% CI=2214-2439 while that of the second-born-female twin was 2325+501g (95% CI=2197-2453 p>0.05. When the birthweight difference exceeded 750g, the probability that Twin I will be heavier than Twin II was 83.3% (5 of 6. Conclusion: Although the first-born twin was more often heavier than their second-born siblings, either could weigh more or less at birth. The larger the birthweight difference between growth-discordant twin pair, the greater the probability that the heavier twin would be delivered first

  5. The morphology of the sella turcica in monozygotic twins.

    Science.gov (United States)

    Brock-Jacobsen, Mette T; Pallisgaard, Carsten; Kjaer, Inger

    2009-12-01

    The purpose was to compare the sella turcica morphology of individuals within pairs of monozygotic twins with normal karyotype and to analyze the similarity between the observed morphology and the morphology of non-twins at the same age with normal karyotype. Profile radiographs from 84 individuals of 42 twin pairs (18 male and 24 female pairs, aged 18-23 years) comprised the material. Sella turcica measurements from non-twins aged 6-21 years were used as normal reference. Length, depth and diameter of the sella turcica were measured and controlled by re-measurements. Pearson's correlation coefficient was used for comparison of individuals within twin pairs. For comparison of twins and non-twins, normal standard values for length, depth and diameter were subtracted from the twin values. For the mean values of these differences, confidence limits p values and t values were calculated. The study showed that the size of the sella turcica may be partly similar and partly dissimilar within the pair of monozygotic twins. Statistical evaluation of the data showed correlations between length, depth and diameter of the sella turcica between the two twin individuals in the same twin pair. Differences in sizes are observed between individuals in the twin material and individuals in the non-twin material. As a conclusion, the twin males were more similar within the twin pair, but deviated more from the non-twin material than the females. Female twins had more discrepancy within the twin pair, but deviated less from the non-twin material than the males.

  6. Exotic Quarks in Twin Higgs Models

    CERN Document Server

    Cheng, Hsin-Chia; Salvioni, Ennio; Tsai, Yuhsin

    2015-01-01

    The Twin Higgs model provides a natural theory for the electroweak symmetry breaking without the need of new particles carrying the standard model gauge charges below a few TeV. In the low energy theory, the only probe comes from the mixing of the Higgs fields in the standard model and twin sectors. However, an ultraviolet completion is required below ~ 10 TeV to remove residual logarithmic divergences. In non-supersymmetric completions, new exotic fermions charged under both the standard model and twin gauge symmetries have to be present to accompany the top quark, thus providing a high energy probe of the model. Some of them carry standard model color, and may therefore be copiously produced at current or future hadron colliders. Once produced, these exotic quarks can decay into a top together with twin sector particles. If the twin sector particles escape the detection, we have the irreducible stop-like signals. On the other hand, some twin sector particles may decay back into the standard model particles ...

  7. Urticaria in monozygotic and dizygotic twins

    DEFF Research Database (Denmark)

    Thomsen, Simon Francis; van der Sluis, Sophie; Kyvik, Kirsten Ohm

    2012-01-01

    Aim. To identify risk factors for urticaria, to determine the relative proportion of the susceptibility to urticaria that is due to genetic factors in an adult clinical twin sample, and to further determine whether the genetic susceptibility to urticaria overlaps with the genetic susceptibility...... to atopic diseases. Methods. A total of 256 complete twin pairs and 63 single twins, who were selected from sibships with self-reported asthma via a questionnaire survey of 21,162 adult twins from the Danish Twin Registry, were clinically interviewed about a history of urticaria and examined for atopic.......36-2.72), P = 0.000; and atopic dermatitis, HR = 1.44 (1.02-2.06), P = 0.041 were significant risk factors for urticaria. After adjustment for sex and age at onset of urticaria in the index twin, the risk of urticaria was increased in MZ cotwins relative to DZ cotwins, HR = 1.42 (0.63-3.18), P = 0...

  8. Acoustic Emission of Deformation Twinning in Magnesium

    Directory of Open Access Journals (Sweden)

    Chengyang Mo

    2016-08-01

    Full Text Available The Acoustic Emission of deformation twinning in Magnesium is investigated in this article. Single crystal testing with combined full field deformation measurements, as well as polycrystalline testing inside the scanning electron microscope with simultaneous monitoring of texture evolution and twin nucleation were compared to testing at the laboratory scale with respect to recordings of Acoustic Emission activity. Single crystal testing revealed the formation of layered twin boundaries in areas of strain localization which was accompanied by distinct changes in the acoustic data. Testing inside the microscope directly showed twin nucleation, proliferation and growth as well as associated crystallographic reorientations. A post processing approach of the Acoustic Emission activity revealed the existence of a class of signals that appears in a strain range in which twinning is profuse, as validated by the in situ and ex situ microscopy observations. Features extracted from such activity were cross-correlated both with the available mechanical and microscopy data, as well as with the Acoustic Emission activity recorded at the laboratory scale for similarly prepared specimens. The overall approach demonstrates that the method of Acoustic Emission could provide real time volumetric information related to the activation of deformation twinning in Magnesium alloys, in spite of the complexity of the propagation phenomena, the possible activation of several deformation modes and the challenges posed by the sensing approach itself when applied in this type of materials evaluation approach.

  9. Imperfect twinning: a clinical and ethical dilemma

    Science.gov (United States)

    Denardin, Daniela; Telles, Jorge Alberto B.; Betat, Rosilene da Silveira; Fell, Paulo Renato K.; da Cunha, André Campos; Targa, Luciano Vieira; Zen, Paulo Ricardo G.; Rosa, Rafael Fabiano M.

    2013-01-01

    OBJECTIVE To review the history, epidemiology, etiology, gestational aspects, diagnosis and prognosis of imperfect twinning. DATA SOURCES Scientific articles were searched in PubMed, SciELO and Lilacs databases, using the descriptors "conjoined twins", "multiple pregnancy", "ultrasound", "magnetic resonance imaging" and "prognosis". The research was not delimited to a specific period of time and was supplemented with bibliographic data from books. DATA SYNTHESIS: The description of conjoined twins is legendary. The estimated frequency is 1/45,000-200,000 births. These twins are monozygotic, monochorionic and usually monoamniotic. They can be classified by the most prominent fusion site, by the symmetry between the conjoined twins or by the sharing structure. The diagnosis can be performed in the prenatal period or after birth by different techniques, such as ultrasound, magnetic resonance imaging and echocardiography. These tests are of paramount importance for understanding the anatomy of both fetuses/children, as well as for prognosis and surgical plan determination. CONCLUSIONS Although imperfect twinning is a rare condition, the prenatal diagnosis is very important in order to evaluate the fusion site and its complexity. Hence, the evaluation of these children should be multidisciplinary, involving mainly obstetricians, pediatricians and pediatric surgeons. However, some decisions may constitute real ethical dilemmas, in which different points should be discussed and analyzed with the health team and the family. PMID:24142323

  10. Laying the ghost of twin paradox

    Directory of Open Access Journals (Sweden)

    Popović Marko

    2009-01-01

    Full Text Available Someone's true age is not written in his ID, but in his biomarkers. Aging process is not caused by time passing, but by thermodynamically laws. Entropy, extent of metabolic reaction, and temperature are Lorentz invariant, so these facts make twin paradox impossible because there is no way for one twin to age slower than the other even if the time in his frame is dilated. Entropy is the function of state, not time. So as much as standard thermodynamics concerns, the path between two points in space is equivalent to the path between two states. Whether the point B is reached by moving faster using the longer way (with time dilatation, or slower by using shortcut (without time dilatation, the state of the system after completing the road should be the same. This is supported by the fact that when two twins reach the same space-time point (point B in which the state parameters are the same. If we use entropy as an age parameter, then both twins have the same entropy value and are exactly the same biological age. Therefore, the twin paradox is a logical mistake based on wrong first premise. Bergson symmetry is not necessary any more to explain the impossibility of twin paradox.

  11. Imperfect twinning: a clinical and ethical dilemma.

    Science.gov (United States)

    Denardin, Daniela; Telles, Jorge Alberto B; Betat, Rosilene da Silveira; Fell, Paulo Renato K; Cunha, André Campos da; Targa, Luciano Vieira; Zen, Paulo Ricardo G; Rosa, Rafael Fabiano M

    2013-09-01

    OBJECTIVE To review the history, epidemiology, etiology, gestational aspects, diagnosis and prognosis of imperfect twinning. DATA SOURCES Scientific articles were searched in PubMed, SciELO and Lilacs databases, using the descriptors "conjoined twins", "multiple pregnancy", "ultrasound", "magnetic resonance imaging" and "prognosis". The research was not delimited to a specific period of time and was supplemented with bibliographic data from books. The description of conjoined twins is legendary. The estimated frequency is 1/45,000-200,000 births. These twins are monozygotic, monochorionic and usually monoamniotic. They can be classified by the most prominent fusion site, by the symmetry between the conjoined twins or by the sharing structure. The diagnosis can be performed in the prenatal period or after birth by different techniques, such as ultrasound, magnetic resonance imaging and echocardiography. These tests are of paramount importance for understanding the anatomy of both fetuses/children, as well as for prognosis and surgical plan determination. CONCLUSIONS Although imperfect twinning is a rare condition, the prenatal diagnosis is very important in order to evaluate the fusion site and its complexity. Hence, the evaluation of these children should be multidisciplinary, involving mainly obstetricians, pediatricians and pediatric surgeons. However, some decisions may constitute real ethical dilemmas, in which different points should be discussed and analyzed with the health team and the family.

  12. The Finnish Twin Cohort Study: an update.

    Science.gov (United States)

    Kaprio, Jaakko

    2013-02-01

    In 2002 and 2006, review papers have described the Finnish Twin Cohort and studies conducted on these population-based, longitudinal data sets with extensive follow-up data. Three cohorts have been established: the older twin cohort in the 1970s, and the Finntwin12 and Finntwin16 studies initiated in the 1990s. The present review provides on update on the latest data collections conducted since the previous review. These cover the fourth waves of data collection in the older cohort (twins born before 1958) and Finntwin12 (twins born 1983-1987). The fifth wave of data collection in Finntwin16 (twins born 1975-1979) also included assessments of their spouses/partners. An analysis of mortality in the older cohort from 1975 to 2009 indicates that the mortality of adult twins (as individuals) does not differ from the population at large. Based on the cohorts, many sub-studies with more detailed phenotyping and collection of omics data have been conducted or are in progress. We also contribute to numerous national and international collaborations.

  13. Imperfect twinning: a clinical and ethical dilemma

    Directory of Open Access Journals (Sweden)

    Daniela Denardin

    2013-09-01

    Full Text Available OBJECTIVE To review the history, epidemiology, etiology, gestational aspects, diagnosis and prognosis of imperfect twinning. DATA SOURCES Scientific articles were searched in PubMed, SciELO and Lilacs databases, using the descriptors "conjoined twins", "multiple pregnancy", "ultrasound", "magnetic resonance imaging" and "prognosis". The research was not delimited to a specific period of time and was supplemented with bibliographic data from books. DATA SYNTHESIS: The description of conjoined twins is legendary. The estimated frequency is 1/45,000-200,000 births. These twins are monozygotic, monochorionic and usually monoamniotic. They can be classified by the most prominent fusion site, by the symmetry between the conjoined twins or by the sharing structure. The diagnosis can be performed in the prenatal period or after birth by different techniques, such as ultrasound, magnetic resonance imaging and echocardiography. These tests are of paramount importance for understanding the anatomy of both fetuses/children, as well as for prognosis and surgical plan determination. CONCLUSIONS Although imperfect twinning is a rare condition, the prenatal diagnosis is very important in order to evaluate the fusion site and its complexity. Hence, the evaluation of these children should be multidisciplinary, involving mainly obstetricians, pediatricians and pediatric surgeons. However, some decisions may constitute real ethical dilemmas, in which different points should be discussed and analyzed with the health team and the family.

  14. Twin pregnancy in the congenital malformed uterus.

    Science.gov (United States)

    Heinonen, Pentti K

    2016-07-01

    The frequency and outcome of twin pregnancies in women with uterine malformation were studied. The cohort comprised 13 (4.9%) women with twin pregnancy found among 263 women. They had 483 deliveries, 13 of them twins (2.7%; 95% CI 1.6-4.6%). Among 38 patients with unicornuate uterus 5 (6.8%) out of 74 deliveries were twins, 39 women with didelphic uterus 2 (3.2%) out of 62 deliveries and 147 women with septate or subseptate uterus 6 (2.3%) out of 264 deliveries were twins. The mean duration of gestation was 249 days (range 190-268 days), 5 (38%) out of 13 deliveries were premature, 25 out of 26 newborns were alive. Mean durations of gestation and mean weights of newborns did not differ when 7 cases with unicornuate or didelphic uterus were compared to 6 cases with complete or partial uterine septum. A congenital malformed uterus can bear twin pregnancy without severe complications apart from prematurity.

  15. Breeding objectives for Targhee sheep.

    Science.gov (United States)

    Borg, R C; Notter, D R; Kuehn, L A; Kott, R W

    2007-11-01

    Breeding objectives were developed for Targhee sheep under rangeland production conditions. Traits considered were those for which EPD were available from the US National Sheep Improvement Program and included direct and maternal effects on 120-d weaning weight (WW and MM, respectively); yearling weight (YW); yearling fleece weight, fiber diameter, and staple length; and percent lamb crop (PLC), measured as the number of lambs born per 100 ewes lambing. A bioeconomic model was used to predict the effects of a change of 1 additive SD in EPD for each trait, holding all other traits constant at their mean, on animal performance, feed requirements, feed costs, and economic returns. Resulting economic weightings were then used to derive selection indexes. Indexes were derived separately for 3 prolificacy levels (1.41, 1.55, and 1.70 lambs/ewe lambing), 2 triplet survival levels (50 and 67%), 2 lamb pricing policies (with or without discounting of prices for heavy feeder lambs), and 3 forage cost scenarios (renting pasture, purchasing hay, or reducing flock size to accommodate increased nutrient requirements for production). Increasing PLC generally had the largest impact on profitability, although an increase in WW was equally important, with low feed costs and no discounting of prices for heavy feeder lambs. Increases in PLC were recommended at all 3 prolificacy levels, but with low triplet survival the value of increasing PLC eventually declined as the mean litter size increased to approximately 2.15 lambs/ewe lambing and above. Increasing YW (independent of WW) increased ewe maintenance costs and reduced profitability. Predicted changes in breeding values for WW and YW under index selection varied with lamb pricing policy and feed costs. With low feed costs or no discounts for heavy lambs, YW increased at a modest rate in association with increasing WW, but with high feed costs or discounting of heavy lambs, genetic trends in WW were reduced by approximately 50% to

  16. Epigenome-wide association study on identical twins discordant for birth weight

    DEFF Research Database (Denmark)

    Tan, Qihua; Nielsen, Morten Frost Munk; Christiansen, Lene

    induces persistent epigenetic modification detectable at adult ages, we performed a genome-wide DNA methylation profiling in peripheral blood of 150 pairs of identical Danish twins discordant for birth weight using the Illumina Infinium HumanMethylation450 BeadChip featuring 485,000 CpG sites across...... the genome. After quality control and data preprocessing using free R package minfi, data were analysed by a mixed effects model including fixed effect variables such as birth weight difference, age and sex of twin pairs; random effect variables such as batch, well, and sample position on the array, etc....... Statistical analysis revealed 12 probes with p valuetwins is not associated...

  17. Salivary cortisol in unaffected twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Vinberg, Maj; Bennike, Bente; Kyvik, Kirsten Ohm

    2008-01-01

    -sectional high-risk study. Healthy monozygotic (MZ) and dizygotic (DZ) twins with (High-Risk twins) and without (Low-Risk twins) a co-twin history of affective disorder were identified through nationwide registers. Awakening and evening salivary cortisol levels were compared between the 190 High- and Low......-Risk twins. The 109 High-Risk twins had significantly higher evening cortisol levels than the 81 Low-Risk MZ twins, also after adjustment for age, sex, and the level of subclinical depressive symptoms. No significant difference was found in awakening cortisol levels between High-Risk and Low-Risk twins....... In conclusion, a high genetic liability to affective disorder was associated with a higher evening cortisol level, but not with awakening cortisol level. Future prospective family, high-risk and twin studies are needed to decide whether abnormalities in the HPA axis can be identified as an endophenotype...

  18. Utilization of FecJ F gene in developing commercial sheep farming : Economic analysis

    Directory of Open Access Journals (Sweden)

    Atien Priyanti

    1996-01-01

    Full Text Available An increase of income per capita in Indonesia is not followed by an increase of numbers and quality of lambs stock. To meet he high demand both for domestic and international markets, sheep production should be elaborated commercially . The Research Institute for Animal Production, Bogor has been able to identify the segregation of FecJ F on Javanese sheep, which has large effect on ovulation rate and number of litters born. The study was purposed to analyse the economic value of using Fed gene and the crossing with St. Croix rams to obtain high number of lamb production as well as high pre-weaning growth rate . Sixty seven Garut ewes were used and classified into three classes of singles, twins and triplets or mom: lambs born . From each litter type, ewes were classified according to the breed of rams to be used . Gamt and St . Croix rams were used to represent small and large size of sires, respectively . The parameters observed were litter size, birth weight, sex, feed consumption, weaning weight and average daily gain . Lambs and ewes were weighed on biweekly and monthly basis, respectively. An increasing of input for single born ewes was not followed by dramatic increase in its body weight at weaning, which means that the optimum level of production was not achieved. This resulted a shortening of farmers income. However, for ewes having twins an increase of input was followed by significantly increased of production level . Therefore, the economic analysis model used for ewes that carry the Fed gene showed an increase of income of Rp.30,691 .50, and Rp.24,319.82, per ewe per period for St. Croix sires and Garut sires, respectively .

  19. Prenatal undernutrition and postnatal overnutrition alter thyroid hormone axis function in sheep.

    Science.gov (United States)

    Johnsen, L; Kongsted, A H; Nielsen, M O

    2013-03-01

    Mounting evidence led us to hypothesize that i) function of the thyroid hormone (TH) axis can be programed by late gestation undernutrition (LG-UN) and ii) early-postnatal-life overnutrition (EL-ON) exacerbates the fetal impacts on TH axis function. In a 2 × 2 factorial experiment, 21 twin-bearing sheep were fed one of two diets during late gestation: NORM (fulfilling energy and protein requirements) or LOW (50% of NORM). From day 3 to 6 months after birth (around puberty), the twin lambs were assigned to each their diet: conventional (CONV) or high-carbohydrate, high-fat, where after half the lambs were killed. Remaining sheep (exclusively females) were fed the same moderate diet until 2 years of age (young adults). At 6 months and 2 years of age, fasting challenges were conducted and target tissues were collected at autopsy. LG-UN caused adult hyperthyroidism associated with increased thyroid expression of genes regulating TH synthesis and deiodination. In one or more of the target tissues, liver, cardiac muscle, and longissimus dorsi muscle, gene expressions were increased by LG-UN for TH receptors (THRA and THRB) and deiodinases but were decreased in visceral and subcutaneous adipose tissues. EL-ON increased TH levels in adolescent lambs, but this was reversed after diet correction and not evident in adulthood. We conclude that LG-UN programed TH axis function at the secretory level and differentially in target tissues, which was increasingly manifested with age. Differential TH signaling in adipose vs other tissues may be part of a mechanism whereby fetal malnutrition can predispose for obesity and other metabolic disorders.

  20. Paternal inheritance of mitochondrial DNA in the sheep (Ovine aries)

    National Research Council Canada - National Science Library

    Zhao, Xingbo; Chu, Mingxing; Li, Ning; Wu, Changxin

    2001-01-01

    Paternal inheritance of mitochondria DNA in sheep was discovered by examination of 152 sheep from 38 hybrid families for mtDNA D-loop polymorphisms using PCR-RFLP, amplification of repeated sequence...