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Sample records for chromosome condensation due

  1. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs

  2. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  3. Novel insights into mitotic chromosome condensation

    Science.gov (United States)

    Piskadlo, Ewa; Oliveira, Raquel A.

    2016-01-01

    The fidelity of mitosis is essential for life, and successful completion of this process relies on drastic changes in chromosome organization at the onset of nuclear division. The mechanisms that govern chromosome compaction at every cell division cycle are still far from full comprehension, yet recent studies provide novel insights into this problem, challenging classical views on mitotic chromosome assembly. Here, we briefly introduce various models for chromosome assembly and known factors involved in the condensation process (e.g. condensin complexes and topoisomerase II). We will then focus on a few selected studies that have recently brought novel insights into the mysterious way chromosomes are condensed during nuclear division.

  4. Stable Chromosome Condensation Revealed by Chromosome Conformation Capture.

    Science.gov (United States)

    Eagen, Kyle P; Hartl, Tom A; Kornberg, Roger D

    2015-11-01

    Chemical cross-linking and DNA sequencing have revealed regions of intra-chromosomal interaction, referred to as topologically associating domains (TADs), interspersed with regions of little or no interaction, in interphase nuclei. We find that TADs and the regions between them correspond with the bands and interbands of polytene chromosomes of Drosophila. We further establish the conservation of TADs between polytene and diploid cells of Drosophila. From direct measurements on light micrographs of polytene chromosomes, we then deduce the states of chromatin folding in the diploid cell nucleus. Two states of folding, fully extended fibers containing regulatory regions and promoters, and fibers condensed up to 10-fold containing coding regions of active genes, constitute the euchromatin of the nuclear interior. Chromatin fibers condensed up to 30-fold, containing coding regions of inactive genes, represent the heterochromatin of the nuclear periphery. A convergence of molecular analysis with direct observation thus reveals the architecture of interphase chromosomes. PMID:26544940

  5. Disruption of human vigilin impairs chromosome condensation and segregation.

    Science.gov (United States)

    Wei, Ling; Xie, Xiaoyan; Li, Junhong; Li, Ran; Shen, Wenyan; Duan, Shuwang; Zhao, Rongce; Yang, Wenli; Liu, Qiuying; Fu, Qiang; Qin, Yang

    2015-11-01

    Appropriate packaging and condensation are critical for eukaryotic chromatin's accommodation and separation during cell division. Human vigilin, a multi-KH-domain nucleic acid-binding protein, is associated with alpha satellites of centromeres. DDP1, a vigilin's homolog, is implicated with chromatin condensation and segregation. The expression of vigilin was previously reported to elevate in highly proliferating tissues and increased in a subset of hepatocellular carcinoma patients. Other studies showed that vigilin interacts with CTCF, contributes to regulation of imprinted genes Igf2/H19, and colocalizes with HP1α on heterochromatic satellite 2 and β-satellite repeats. These studies indicate that human vigilin might be involved in chromatin remodeling and regular cell growth. To investigate the potential role of human vigilin in cell cycle, the correlations between vigilin and chromosomal condensation and segregation were studied. Depletion of human vigilin by RNA interference in HepG2 cells resulted in chromosome undercondensation and various chromosomal defects during mitotic phase, including chromosome misalignments, lagging chromosomes, and chromosome bridges. Aberrant polyploid nucleus in telophase was also observed. Unlike the abnormal staining pattern of chromosomes, the shape of spindle was normal. Furthermore, the chromatin showed a greater sensitivity to MNase digestion. Collectively, our findings show that human vigilin apparently participates in chromatin condensation and segregation. PMID:26032007

  6. Frequency of primary amenorrhea due to chromosomal aberration

    International Nuclear Information System (INIS)

    Objective: To find out the frequency of primary amenorrhea due to chromosomal aberration and the different options available for management. Subjects and Methods: All patients with primary amenorrhea due to chromosomal aberrations were included in study. Patient's detailed history, general physical examination, presence or absence of secondary sexual characteristics, abdominal and pelvic examination finding were noted. Targeted investigations, including ultrasound, hormonal assay, buccal smear and karyotyping results were recorded. The management options were individually tailored with focus n psychological management. Results: Eighteen patients out of 30,000 patients were diagnosed as having primary amenorrhea. Six had primary amenorrhea due to chromosomal aberrations with the frequency of 0.02%. The age at presentation was 20 years and above in 50%. The most common cause was Turner's syndrome seen in 4 out of 6. The presenting symptoms were delay in onset of menstruation in 05 patients and primary infertility in 01 patient. Conclusion: Primary amenorrhea due to chromosomal aberration is an uncommon condition requiring an early and accurate diagnosis. Turner's syndrome is a relatively common cause of this condition. Management should be multi-disciplinary and individualized according to the patient's age and symptom at presentation. Psychological management is very important and counselling throughout treatment is recommended. (author)

  7. Detection and Automated Scoring of Dicentric Chromosomes in Nonstimulated Lymphocyte Prematurely Condensed Chromosomes After Telomere and Centromere Staining

    Energy Technology Data Exchange (ETDEWEB)

    M' kacher, Radhia [Laboratoire de Radiobiologie et Oncologie, Commissariat à l' Energie Atomique, Fontenay-aux-Roses (France); El Maalouf, Elie [Laboratoire de Radiobiologie et Oncologie, Commissariat à l' Energie Atomique, Fontenay-aux-Roses (France); Laboratoire Modélisation Intelligence Processus Systèmes (MIPS)–Groupe TIIM3D, Université de Haute-Alsace, Mulhouse (France); Terzoudi, Georgia [Laboratory of Radiobiology & Biodosimetry, National Center for Scientific Research Demokritos, Athens (Greece); Ricoul, Michelle [Laboratoire de Radiobiologie et Oncologie, Commissariat à l' Energie Atomique, Fontenay-aux-Roses (France); Heidingsfelder, Leonhard [MetaSystems, Altlussheim (Germany); Karachristou, Ionna [Laboratory of Radiobiology & Biodosimetry, National Center for Scientific Research Demokritos, Athens (Greece); Laplagne, Eric [Pole Concept, Paris (France); Hempel, William M. [Laboratoire de Radiobiologie et Oncologie, Commissariat à l' Energie Atomique, Fontenay-aux-Roses (France); Colicchio, Bruno; Dieterlen, Alain [Laboratoire Modélisation Intelligence Processus Systèmes (MIPS)–Groupe TIIM3D, Université de Haute-Alsace, Mulhouse (France); Pantelias, Gabriel [Laboratory of Radiobiology & Biodosimetry, National Center for Scientific Research Demokritos, Athens (Greece); Sabatier, Laure, E-mail: laure.sabatier@cea.fr [Laboratoire de Radiobiologie et Oncologie, Commissariat à l' Energie Atomique, Fontenay-aux-Roses (France)

    2015-03-01

    Purpose: To combine telomere and centromere (TC) staining of premature chromosome condensation (PCC) fusions to identify dicentrics, centric rings, and acentric chromosomes, making possible the realization of a dose–response curve and automation of the process. Methods and Materials: Blood samples from healthy donors were exposed to {sup 60}Co irradiation at varying doses up to 8 Gy, followed by a repair period of 8 hours. Premature chromosome condensation fusions were carried out, and TC staining using peptide nucleic acid probes was performed. Chromosomal aberration (CA) scoring was carried out manually and automatically using PCC-TCScore software, developed in our laboratory. Results: We successfully optimized the hybridization conditions and image capture parameters, to increase the sensitivity and effectiveness of CA scoring. Dicentrics, centric rings, and acentric chromosomes were rapidly and accurately detected, leading to a linear-quadratic dose–response curve by manual scoring at up to 8 Gy. Using PCC-TCScore software for automatic scoring, we were able to detect 95% of dicentrics and centric rings. Conclusion: The introduction of TC staining to the PCC fusion technique has made possible the rapid scoring of unstable CAs, including dicentrics, with a level of accuracy and ease not previously possible. This new approach can be used for biological dosimetry in radiation emergency medicine, where the rapid and accurate detection of dicentrics is a high priority using automated scoring. Because there is no culture time, this new approach can also be used for the follow-up of patients treated by genotoxic therapy, creating the possibility to perform the estimation of induced chromosomal aberrations immediately after the blood draw.

  8. Detection and Automated Scoring of Dicentric Chromosomes in Nonstimulated Lymphocyte Prematurely Condensed Chromosomes After Telomere and Centromere Staining

    International Nuclear Information System (INIS)

    Purpose: To combine telomere and centromere (TC) staining of premature chromosome condensation (PCC) fusions to identify dicentrics, centric rings, and acentric chromosomes, making possible the realization of a dose–response curve and automation of the process. Methods and Materials: Blood samples from healthy donors were exposed to 60Co irradiation at varying doses up to 8 Gy, followed by a repair period of 8 hours. Premature chromosome condensation fusions were carried out, and TC staining using peptide nucleic acid probes was performed. Chromosomal aberration (CA) scoring was carried out manually and automatically using PCC-TCScore software, developed in our laboratory. Results: We successfully optimized the hybridization conditions and image capture parameters, to increase the sensitivity and effectiveness of CA scoring. Dicentrics, centric rings, and acentric chromosomes were rapidly and accurately detected, leading to a linear-quadratic dose–response curve by manual scoring at up to 8 Gy. Using PCC-TCScore software for automatic scoring, we were able to detect 95% of dicentrics and centric rings. Conclusion: The introduction of TC staining to the PCC fusion technique has made possible the rapid scoring of unstable CAs, including dicentrics, with a level of accuracy and ease not previously possible. This new approach can be used for biological dosimetry in radiation emergency medicine, where the rapid and accurate detection of dicentrics is a high priority using automated scoring. Because there is no culture time, this new approach can also be used for the follow-up of patients treated by genotoxic therapy, creating the possibility to perform the estimation of induced chromosomal aberrations immediately after the blood draw

  9. A novel MCPH1 isoform complements the defective chromosome condensation of human MCPH1-deficient cells.

    Directory of Open Access Journals (Sweden)

    Ioannis Gavvovidis

    Full Text Available Biallelic mutations in MCPH1 cause primary microcephaly (MCPH with the cellular phenotype of defective chromosome condensation. MCPH1 encodes a multifunctional protein that notably is involved in brain development, regulation of chromosome condensation, and DNA damage response. In the present studies, we detected that MCPH1 encodes several distinct transcripts, including two major forms: full-length MCPH1 (MCPH1-FL and a second transcript lacking the six 3' exons (MCPH1Δe9-14. Both variants show comparable tissue-specific expression patterns, demonstrate nuclear localization that is mediated independently via separate NLS motifs, and are more abundant in certain fetal than adult organs. In addition, the expression of either isoform complements the chromosome condensation defect found in genetically MCPH1-deficient or MCPH1 siRNA-depleted cells, demonstrating a redundancy of both MCPH1 isoforms for the regulation of chromosome condensation. Strikingly however, both transcripts are regulated antagonistically during cell-cycle progression and there are functional differences between the isoforms with regard to the DNA damage response; MCPH1-FL localizes to phosphorylated H2AX repair foci following ionizing irradiation, while MCPH1Δe9-14 was evenly distributed in the nucleus. In summary, our results demonstrate here that MCPH1 encodes different isoforms that are differentially regulated at the transcript level and have different functions at the protein level.

  10. Damping of condensate collective modes due to equilibration with the non-condensate

    OpenAIRE

    Williams, J. E.; Griffin, A.

    2000-01-01

    We consider the damping of condensate collective modes at finite temperatures arising from lack of equilibrium between the condensate and the non-condensate atoms, an effect that is ignored in the usual discussion of the collisionless region. As a first approximation, we ignore the dynamics of the thermal cloud. Our calculations should be applicable to collective modes of the condensate which are oscillating out-of-phase with the thermal cloud. We obtain a generalized Stringari equation of mo...

  11. Chromosome painting and prematurely condensed chromosomes (PCC) - new methods of biological dosimetry

    International Nuclear Information System (INIS)

    Classic methods of biological dosimetry - micronucleus and dicentric assay pose several problems. In the case of micronucleus there is a wide range of spontaneous frequencies and smoking and age are powerfull contributing factors. In the case of dicentrics - low mitotic index in some individuals especially in the elderly or accidentally exposed to high radiation doses. So, there are 2 quite new molecular techniques which at least in part solve these problems: chromosome painting and PCC. Chromosome painting by employing chromosome-specific DNA probes allow easy identification and quantification of translocations. recently, it was shown that calyculin A or okadaic acid, inhibitors of 1 and 2A protein phosphatases, induce PCC in peripheral blood cells. This is an easy biodosimetric method with a high PCC index and independent of the ability of cells to divide e.g. after high (20 Gy) doses when the mitotic index is extremely low. (author)

  12. DOSE RESPONSE CURVE OF 60Co FOR PREMATURE CONDENSED CHROMOSOME FRAGMENTS OF HUMAN LYMPHOCYTES

    Institute of Scientific and Technical Information of China (English)

    高锦声; 郑斯英; 等

    1995-01-01

    The dose-response curves obtained by premature condensed chromosome(PCC) and conventional cellular genetic methods can be represented by two linear equations.The ratio of the slopes,KPCC/KM1,is about 28,In compartison to the conventional method.The PCC method has many advantages;e.g.it is faster,simopler,more sensitive and accurate.Its significance in the study of radiation damage is also discussed.

  13. A model for the condensation of the bacterial chromosome by the partitioning protein ParB

    Science.gov (United States)

    Broedersz, Chase; Wingreen, Ned

    2013-03-01

    The molecular machinery responsible for faithful segregation of the chromosome in bacteria such as Caulobacter crescentus and Bacillus subtilis includes the ParABS a.k.a. Spo0J/Soj partitioning system. In Caulobacter, prior to division, hundreds of ParB proteins bind to the DNA near the origin of replication, and localize to one pole of the cell. Subsequently, the ParB-DNA complex is translocated to the far pole by the binding and retraction of the ParA spindle-like apparatus. Remarkably, the localization of ParB proteins to specific regions of the chromosome appears to be controlled by only a few centromeric parS binding sites. Although lateral interactions between DNA-bound ParB are likely to be important for their localization, the long-range order of ParB domains on the chromosome appears to be inconsistent with a picture in which protein-protein interactions are limited to neighboring DNA-bound proteins. We developed a coarse-grained Brownian dynamics model that allows for lateral and 3D protein-protein interactions among bound ParB proteins. Our model shows how such interactions can condense and organize the DNA spatially, and can control the localization and the long-range order of the DNA-bound proteins.

  14. A small (sSMC) chromosome 22 due to a maternal translocation between chromosomes 8 and 22: a case report.

    Science.gov (United States)

    Mundhofir, F E P; Kooper, A J A; Winarni, T I; Smits, A P T; Faradz, S M H; Hamel, B C J

    2010-01-01

    We report on a boy with partial trisomies for chromosomes 8 and 22 caused by the presence of a small supernumerary marker chromosome (sSMC), a der(22)t(8;22)(p22;q11.21), inherited from a t(8;22)(p22;q11.21) translocation carrier mother. He has mild mental retardation, unability to speak distinct words and several minor anomalies i.e. high forehead and hairline, telecanthus, upslanting palpebral fissures, depressed nasal bridge, nail hypoplasia, toe position anomaly and 5th finger clinodactyly. He has two maternal uncles and one maternal aunt with mental retardation. G-banding technique showed 47,XY,+mar whilst his mother's karyotype showed a balanced reciprocal translocation between the chromosomes 8 and 22. Fluorescence In Situ Hybridization (FISH) technique with probes for centromere 22 and 8pter were used to detect the origin of marker chromosome and confirmed the marker chromosome in the proband showing to be extra chromosomal material originated from chromosome 8 and 22. Additional genome wide microarray analysis, using the Affymetrix Nspl 250K SNP array platform was performed to further characterize the marker chromosome and resulted in a der(22)t(8;22)(p22;q11.21). Furthermore, cytogenetic analysis of three affected family members showed the same unbalanced translocation, due to 3:1 meiotic segregation. This indicated the viability of this unbalanced pattern and combined with the recurrent miscarriages by the proband's mother, the mechanism of transmitting extrachromosomal material is probably not a random process. Since, there is no similar translocation (8p;22q) reported and the chromosomal translocation largely exists of additional 8p22-8pter we compare the clinical outcomes with reported cases of 8p22-8pter triplication, although there is a part of genetic material derived from chromosome 22 present. This unique familial chromosome translocation case from Indonesia will give insight in the underlying mechanism of this recurrent chromosomal abnormality

  15. Rapid assessment of high-dose radiation exposures through scoring of cell-fusion-induced premature chromosome condensation and ring chromosomes.

    Science.gov (United States)

    Lamadrid Boada, A I; Romero Aguilera, I; Terzoudi, G I; González Mesa, J E; Pantelias, G; García, O

    2013-09-18

    Analysis of premature chromosome condensation (PCC) mediated by fusion of G0-lymphocytes with mitotic CHO cells in combination with rapid visualization and quantification of rings (PCC-Rf) is proposed as an alternative technique for dose assessment of radiation-exposed individuals. Isolated lymphocytes or whole blood from six individuals were γ-irradiated with 5, 10, 15 and 20Gy at a dose rate of 0.5Gy/min. Following either 8- or 24-h post-exposure incubation of irradiated samples at 37°C, chromosome spreads were prepared by standard PCC cytogenetic procedures. The protocol for PCC fusion proved to be effective at doses as high as 20Gy, enabling the analysis of ring chromosomes and excess PCC fragments. The ring frequencies remained constant during the 8-24-h repair time; the pooled dose relationship between ring frequency (Y) and dose (D) was linear: Y=(0.088±0.005)×D. During the repair time, excess fragments decreased from 0.91 to 0.59 chromatid pieces per Gy, revealing the importance of information about the exact time of exposure for dose assessment on the basis of fragments. Compared with other cytogenetic assays to estimate radiation dose, the PCC-Rf method has the following benefits: a 48-h culture time is not required, allowing a much faster assessment of dose in comparison with conventional scoring of dicentrics and rings in assays for chemically-induced premature chromosome condensation (PCC-Rch), and it allows the analysis of heavily irradiated lymphocytes that are delayed or never reach mitosis, thus avoiding the problem of saturation at high doses. In conclusion, the use of the PCC fusion assay in conjunction with scoring of rings in G0-lymphocytes offers a suitable alternative for fast dose estimation following accidental exposure to high radiation doses.

  16. Comparison of clonogenic assay with premature chromosome condensation assay in prediction of human cell radiosensitivity

    Institute of Scientific and Technical Information of China (English)

    Zhuan-Zi Wang; Wen-Jian Li; Hong Zhang; Jian-She Yang; Rong Qiu; Xiao Wang

    2006-01-01

    AIM: To determine whether the number of non-rejoining G2-chromatid breaks can predict the radiosensitivity of human cell lines.METHODS: Cell lines of human ovary carcinoma cells (HO8910), human hepatoma cells (HepG2) and liver cells (L02) were irradiated with a range of doses and assessed both of cell survival and non-rejoining G2-chromatid breaks at 24 h after irradiation. Cell survival was documented by a colony assay. Non-rejoining G2-chromatid breaks were measured by counting the number of non-rejoining G2 chromatid breaks at 24 h after irradiation, detected by the prematurely chromosome condensed (PCC) technique.RESULTS: A linear-quadratic survival curve was observed in three cell lines, and HepG2 was the most sensitive to y-radiation. A dose-dependent linear increase was observed in radiation-induced non-rejoining G2-PCC breaks measured at 24 h after irradiation in all cell lines, and HepG2 was the most susceptible to induction of non-rejoining G2-PCC breaks. A close correlation was found between the clonogenic radiosensitivity and the radiation-induced non-rejoining G2-PCC breaks (r= 0.923). Furthermore, survival-aberration correlations for two or more than two doses lever were also significant.CONCLUSION: The number of non-rejoining G2 PCC breaks holds considerable promise for predicting the radiosensitivity of normal and tumor cells when two or more than two doses lever is tested.

  17. Further patient with Angelman syndrome due to paternal disomy of chromosome 15 and a milder phenotype

    Energy Technology Data Exchange (ETDEWEB)

    Gillessen-Kaesbach, G.; Passarge, E.; Horsthemke, B. [Institut fuer Humangenetik, Essen (Germany)

    1995-04-10

    This {open_quotes}Letter to the Editor{close_quotes} decribes a patient with Angelman syndrome due to paternal uniparental disomy of chromosome 15 and a milder phenotype compared to Angelman syndrome patients with a 15q deletion. 10 refs., 1 fig.

  18. Stress induced by premature chromatin condensation triggers chromosome shattering and chromothripsis at DNA sites still replicating in micronuclei or multinucleate cells when primary nuclei enter mitosis.

    Science.gov (United States)

    Terzoudi, Georgia I; Karakosta, Maria; Pantelias, Antonio; Hatzi, Vasiliki I; Karachristou, Ioanna; Pantelias, Gabriel

    2015-11-01

    Combination of next-generation DNA sequencing, single nucleotide polymorphism array analyses and bioinformatics has revealed the striking phenomenon of chromothripsis, described as complex genomic rearrangements acquired in a single catastrophic event affecting one or a few chromosomes. Via an unproven mechanism, it is postulated that mechanical stress causes chromosome shattering into small lengths of DNA, which are then randomly reassembled by DNA repair machinery. Chromothripsis is currently examined as an alternative mechanism of oncogenesis, in contrast to the present paradigm that considers a stepwise development of cancer. While evidence for the mechanism(s) underlying chromosome shattering during cancer development remains elusive, a number of hypotheses have been proposed to explain chromothripsis, including ionizing radiation, DNA replication stress, breakage-fusion-bridge cycles, micronuclei formation and premature chromosome compaction. In the present work, we provide experimental evidence on the mechanistic basis of chromothripsis and on how chromosomes can get locally shattered in a single catastrophic event. Considering the dynamic nature of chromatin nucleoprotein complex, capable of rapid unfolding, disassembling, assembling and refolding, we first show that chromatin condensation at repairing or replicating DNA sites induces the mechanical stress needed for chromosome shattering to ensue. Premature chromosome condensation is then used to visualize the dynamic nature of interphase chromatin and demonstrate that such mechanical stress and chromosome shattering can also occur in chromosomes within micronuclei or asynchronous multinucleate cells when primary nuclei enter mitosis. Following an aberrant mitosis, chromosomes could find themselves in the wrong place at the wrong time so that they may undergo massive DNA breakage and rearrangement in a single catastrophic event. Specifically, our results support the hypothesis that premature chromosome

  19. Chromosome

    Science.gov (United States)

    Chromosomes are structures found in the center (nucleus) of cells that carry long pieces of DNA. DNA ... is the building block of the human body. Chromosomes also contain proteins that help DNA exist in ...

  20. Nonlinear Zeno dynamics due to atomic interactions in Bose–Einstein condensate

    International Nuclear Information System (INIS)

    We show that nonlinear interactions induce both the Zeno and anti-Zeno effects in the generalized Bose–Josephson model (with the on-site interactions and the second-order tunneling) describing Bose–Einstein condensate in double-well trap subject to particle removal from one of the wells. We find that the on-site interactions induce only the Zeno effect, which appears at long evolution times, whereas the second-order tunneling leads to a strong decay of the atomic population at short evolution times, reminiscent of the anti-Zeno effect, and destroys the nonlinear Zeno effect due to the on-site interactions at long times

  1. Nonlinear Zeno dynamics due to atomic interactions in Bose–Einstein condensate

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, V.G.; Shchesnovich, V.S., E-mail: valery@ufabc.edu.br

    2014-12-01

    We show that nonlinear interactions induce both the Zeno and anti-Zeno effects in the generalized Bose–Josephson model (with the on-site interactions and the second-order tunneling) describing Bose–Einstein condensate in double-well trap subject to particle removal from one of the wells. We find that the on-site interactions induce only the Zeno effect, which appears at long evolution times, whereas the second-order tunneling leads to a strong decay of the atomic population at short evolution times, reminiscent of the anti-Zeno effect, and destroys the nonlinear Zeno effect due to the on-site interactions at long times.

  2. Resistance to β-Lactams in Neisseria ssp Due to Chromosomally Encoded Penicillin-Binding Proteins

    Directory of Open Access Journals (Sweden)

    André Zapun

    2016-09-01

    Full Text Available Neisseria meningitidis and Neisseria gonorrhoeae are human pathogens that cause a variety of life-threatening systemic and local infections, such as meningitis or gonorrhoea. The treatment of such infection is becoming more difficult due to antibiotic resistance. The focus of this review is on the mechanism of reduced susceptibility to penicillin and other β-lactams due to the modification of chromosomally encoded penicillin-binding proteins (PBP, in particular PBP2 encoded by the penA gene. The variety of penA alleles and resulting variant PBP2 enzymes is described and the important amino acid substitutions are presented and discussed in a structural context.

  3. Angelman syndrome due to paternal uniparental disomy of chromosome 15: A milder phenotype?

    Energy Technology Data Exchange (ETDEWEB)

    Bottani, A.; Robinson, W.P.; DeLoizer-Blanchet, C.D.; Engel, E.; Morris, M.A.; Schmitt, Thun-Hohenstein, L.; Schinzel, A. [Univ. of Zuerich (Switzerland)

    1994-05-15

    The Angelman syndrome (AS) is a neurological disorder characterized by severe mental retardation, absent speech, seizures, gait disturbances, and a typical age-dependent facial phenotype. Most cases are due to an interstitial deletion on the maternally inherited chromosome 15, in the critical region q11-q13. Rare cases also result from paternal uniparental disomy of chromosome 15. In a group of 14 patients with sporadic AS diagnosed in Switzerland, we found 2 unrelated females with paternal isodisomy for the entire chromosome 15. Their phenotypes were milder than usually seen in this syndrome: one girl did not show the typical AS facial changes; both patients had late-onset mild seizures; as they grow older, they had largely undisturbed gross motor functions, in particular no severe ataxia. Both girls were born to older fathers (45 and 43 years old, respectively). The apparent association of a relatively milder phenotype in AS with paternal uniparental disomy will have to be confirmed by detailed clinical descriptions of further patients. 25 refs., 2 figs., 1 tab.

  4. PTP-S2, a nuclear tyrosine phosphatase, is phosphorylated and excluded from condensed chromosomes during mitosis

    Indian Academy of Sciences (India)

    Sundaram Nambirajan; Vegesna Radha; Shubhangi Kamatkar; Ghanshyam Swarup

    2000-03-01

    PTP-S2 is a tyrosine specific protein phosphatase that binds to DNA and is localized to the nucleus in association with chromatin. It plays a role in the regulation of cell proliferation. Here we show that the subcellular distribution of this protein changes during cell division. While PTP-S2 was localized exclusively to the nucleus in interphase cells, during metaphase and anaphase it was distributed throughout the cytoplasm and excluded from condensed chromosomes. At telophase PTP-S2 began to associate with chromosomes and at cytokinesis it was associated with chromatin in the newly formed nucleus. It was hyperphosphorylated and showed retarded mobility in cells arrested in metaphase. In vitro experiments showed that it was phosphorylated by CK2 resulting in mobility shift. Using a deletion mutant we found that CK2 phosphorylated PTP-S2 in the C-terminal non-catalytic domain. A heparin sensitive kinase from mitotic cell extracts phosphorylated PTP-S2 resulting in mobility shift. These results are consistent with the suggestion that during metaphase PTP-S2 is phosphorylated (possibly by CK2 or a CK2-like enzyme), resulting in its dissociation from chromatin.

  5. Condensation and localization of the partitioning protein ParB on the bacterial chromosome

    OpenAIRE

    Broedersz, Chase P.; Wang, Xindan; Meir, Yigal; Loparo, Joseph J.; Rudner, David Z.; Wingreen, Ned S.

    2014-01-01

    The ParABS system is responsible for chromosome and plasmid segregation in many bacteria. A large, coherent ParB–DNA complex forms the partitioning module at the heart of this segregation machinery. Here we provide a simple theoretical model for interacting proteins on DNA to elucidate the structure of the ParB–DNA complex. We show that that both 3D bridging and 1D spreading interactions between DNA-bound ParB proteins are required to ensure the formation of a coherent protein–DNA complex. Th...

  6. Dynamic characteristics of the steam condensation due to a multi-hole sparger

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiangbin [North China Electric Power Univ., Beijing (China). School of Nuclear Science and Engineering; Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy (China); Li, Nan [Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy (China); Zhang, Mengchao [China Power Engineering Consulting (Group) Investment Co. LTD, Beijing (China)

    2016-06-15

    In order to deeply understand the mechanism of the steam jet with a multi-hole sparger, the dynamic characteristics of direct contact condensation of the steam submerged in a subcooled water pool are simulated by means of commercial software. The jet shapes are compared with experimental results. It is found that the numerical results were in good agreement with the experimental ones.

  7. Thermal structures of accreting neutron stars with neutrino losses due to strong pion condensations

    CERN Document Server

    Matsuo, Yasuhide; Hayashida, Koutarou; Liu, Helei; Noda, Tsuneo; Fujimoto, Masayuki Y

    2016-01-01

    Quiescent X-ray luminosities are presented in low mass X-ray binaries with use of evolutionary calculations. The calculated luminosities are compared with observed ones in terms of timeaveraged mass accretion rate. It is shown that neutrino emission by strong pion condensation can explain quiescent X-ray luminosity of SAX J1808.4-3658 and we do not need direct Urca processes concerning nucleons and/or hyperons.

  8. Are the Angular Correlations in pA Collisions due to a Glasmion or Bose Condensation ?

    CERN Document Server

    Dumitru, Adrian; McLerran, Larry

    2014-01-01

    Experiments at the LHC have recently reported results on the angular asymmetry coefficients $v_n[m]$, for various angular moments $n$ and orders of cumulants $m$, in high multiplicity p+Pb collisions. These coefficients are large, and have both even and odd moments. We discuss here some of the implications of these results for our understanding of the initial state of the collision (Color Glass Condensate) and for the evolution in the final state (Glasma and thermalized Quark Gluon Plasma). We show the Color Glass Condensate predicts large even moments, $v_n$ with $n$ an even integer. Odd moments are generated by final state interactions or fragmentation. For a multi-particle determination of $v_2[m]$, where m is the number of particles used to determine the correlation, we argue that if these coefficients approach equality for large $m$ in high multiplicity events, this may imply the existence of either solitonic solutions or Bose condensation either for the JIMWLK action that describes the CGC, or for the G...

  9. Continuous growth of droplet size variance due to condensation in turbulent clouds

    CERN Document Server

    Sardina, Gaetano; Brandt, Luca; Caballero, Rodrigo

    2015-01-01

    We use a stochastic model and direct numerical simulation to study the impact of turbulence on cloud droplet growth by condensation. We show that the variance of the droplet size distribution increases in time as $t^{1/2}$, with growth rate proportional the large-to-small turbulent scale separation and to the turbulence integral scales but independent of the smallest turbulence scale. Direct numerical simulations confirm this result and produce realistically broad droplet size spectra over time intervals of 20 minutes, comparable with the time of rain formation.

  10. Force on a slow moving impurity due to thermal and quantum fluctuations in a 1D Bose-Einstein condensate

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, David [Los Alamos National Laboratory; Sykes, Andrew [UNIV OF QUEENSLAND

    2009-01-01

    We study the drag force acting on an impurity moving through a 1D Bose-Einstein condensate in the presence of both quantum and thermal fluctuations. We are able to find exact analytical solutions of the partial differential equations to the level of the Bogoliubov approximation. At zero temperature, we find a nonzero force is exerted on the impurity at subcritical velocities, due to the scattering of quantum fluctuations. We make the following explicit assumptions: far from the impurity the system is in a quantum state given by that of a zero (or finite) temperature Bose-Einstein condensate, and the scattering process generates only causally related reflection/transmission. The results raise unanswered questions in the quantum dynamics associated with the formation of persistent currents.

  11. Characterization of partial trisomy 9p due to insertional translocation by chromosomal (micro)FISH

    NARCIS (Netherlands)

    de Pater, JM; Ippel, PF; van Dam, WM; Loneus, WH; Engelen, JJM

    2002-01-01

    We describe a family with an insertion 12;9 translocation occurring in a balanced form in a mother and two sons, but in an unbalanced form in the proband, resulting in trisomy of chromosome region 9p22-->9p24. The proband manifests typical features of trisomy 9p; the clinical signs were mental and g

  12. A Fetus with Hb Bart's Disease Due to Maternal Uniparental Disomy for Chromosome 16.

    Science.gov (United States)

    Au, Patrick K C; Kan, Anita S Y; Tang, Mary H Y; Leung, Kwok Y; Chan, Kelvin Y K; Tang, Tommy W F; Lau, Elizabeth T

    2016-01-01

    We here report an unusual case of Hb Bart's (γ4) disease. Thalassemia screening of a couple showed that the wife was an α(0)-thalassemia (α(0)-thal) carrier and her husband's mean corpuscular volume (MCV) was normal. Chorionic villus sampling (CVS) was performed at 13 weeks' gestation for positive Down syndrome screening and chromosomal study of the cultured CVS showed a normal karyotype. Ultrasound examination at 22 weeks' gestation showed fetal cardiomegaly and raised middle cerebral artery peak systolic velocity. Cordocentesis confirmed fetal anemia and showed Hb Bart's disease. Multiplex gap-polymerase chain reaction (gap-PCR) for α-thal deletions on DNA extracted from the CVS showed the presence of a homozygous α(0)-thal - -(SEA) (Southeast Asian) deletion. The husband was found to be a carrier of the α(+)-thal -α(3.7) (rightward) deletion. Non paternity was excluded by fluorescent PCR using short tandem repeat (STR) markers on chromosomes 13, 18 and 21. A de novo terminal deletion of chromosome 16 was excluded by array comparative genomic hybridization (aCGH). Detection of uniparental disomy (UPD), using STR markers on chromosome 16 showed maternal uniparental isodisomy from 16pter to 16p13.2, and uniparental heterodisomy from 16p13.13 to 16qter. PMID:26574185

  13. Superconductivity due to Condensation of Monopoles around RCD Strings in SU(2 Gauge Theory

    Directory of Open Access Journals (Sweden)

    B. S. Rajput

    2010-01-01

    Full Text Available The study of the condensation of monopoles and the resulting chromomagnetic superconductivity have been undertaken in restricted chromodynamics of SU(2 gauge theory. Constructing the RCD Lagrangian and the partition function for monopoles in terms of string action and the action of the current around the strings, the monopole current in RCD chromo magnetic superconductor has been derived and it has shown that in London' limit the penetration length governs the monopole density around RCD string in chromo magnetic superconductors while with finite (nonzero coherence length the leading behavior of the monopole density at large distances from the string is controlled by the coherence length and not by the penetration length.

  14. ATR-16 due to a de novo complex rearrangement of chromosome 16.

    Science.gov (United States)

    Gallego, Marta S; Zelaya, Gabriela; Feliu, Aurora S; Rossetti, Liliana; Shaffer, Lisa G; Bailey, Kristen A; Bacino, Carlos A; Barreiro, Cristina Z

    2005-01-01

    We describe a child with ATR-16 [alpha-thalassemia (thal)/mental retardation], who was referred for genetic evaluation because of minor anomalies and developmental delay. Cytogenetic analysis demonstrated a de novo complex rearrangement of chromosome 16. Fluorescence in situ hybridization (FISH) analysis, using chromosome 16 subtelomeric probes, showed that this patient had a deletion of the distal short arm of chromosome 16 that contains the alpha-globin genes and a duplication of 16q. Analysis of the alpha-globin locus by Southern blot showed a half normal dose of the alpha-globin gene. Microsatellite marker studies revealed that the duplicated 16q region was maternal in origin. Hematological studies revealed anemia, hypochromia and occasional cells with Hb H inclusion bodies. A hematological screening for alpha-thal should be considered in patients with mild developmental delay and a suggestive phenotype of ATR-16 with microcytic hypochromic anemia and normal iron status. The stellate pattern of the iris, a new finding in our patient, may contribute to a better clinical delineation of both syndromes, ATR-16 and/or duplication of 16qter.

  15. Normal newborn with prenatal suspicion of X chromosome monosomy due to confined placental mosaicism.

    Science.gov (United States)

    Serapinas, Danielius; Bartkeviciene, Daiva; Valantinaviciene, Emilija; Machtejeviene, Egle

    2016-10-01

    The recent introduction of cell-free DNA (cfDNA)-based noninvasive prenatal testing (NIPT) offers pregnant women a more accurate method than traditional serum screening methods for detecting fetal aneuploidies. Clinical trials have demonstrated the efficacy of NIPT for Down, Edwards and Patau syndromes. However NIPT approaches that take advantage of single-nucelotide polymorphism (SNP) information potentially allow the identification of triploidy, chromosomal microdeletion syndromes and other unusual genetic variants. To highlight this approach of NIPT we present a rare case of confined placental X chromosome monosomy mosaicism that was prenatally suspected with a single-nucleotide polymorphism-based noninvasive prenatal test. The results of invasive tests (amniocentesis) showed small proportion of X chromosome mosaicism (45, X[5]/46, XX[95]). After birth karyotype of the girl revealed no abnormalities (46 XX), confirming that mosaicism was limited to the placenta. These results highlight the need of patient's informed consent and thorough pretest and postest counseling to ensure that they understand the limitations and advantages of the tests and the implications of the resultss. PMID:27606664

  16. Caffeine-Induced Premature Chromosome Condensation Results in the Apoptosis-Like Programmed Cell Death in Root Meristems of Vicia faba.

    Directory of Open Access Journals (Sweden)

    Dorota Rybaczek

    Full Text Available We have demonstrated that the activation of apoptosis-like programmed cell death (AL-PCD was a secondary result of caffeine (CF induced premature chromosome condensation (PCC in hydroxyurea-synchronized Vicia faba root meristem cells. Initiation of the apoptotic-like cell degradation pathway seemed to be the result of DNA damage generated by treatment with hydroxyurea (HU [double-stranded breaks (DSBs mostly] and co-treatment with HU/CF [single-stranded breaks (SSBs mainly]. A single chromosome comet assay was successfully used to study different types of DNA damage (neutral variant-DSBs versus alkaline-DSBs or SSBs. The immunocytochemical detection of H2AXS139Ph and PARP-2 were used as markers for DSBs and SSBs, respectively. Acridine orange and ethidium bromide (AO/EB were applied for quantitative immunofluorescence measurements of dead, dying and living cells. Apoptotic-type DNA fragmentation and positive TUNEL reaction finally proved that CF triggers AL-PCD in stressed V. faba root meristem cells. In addition, the results obtained under transmission electron microscopy (TEM further revealed apoptotic-like features at the ultrastructural level of PCC-type cells: (i extensive vacuolization; (ii abnormal chromatin condensation, its marginalization and concomitant degradation; (iii formation of autophagy-like vesicles (iv protoplast shrinkage (v fragmentation of cell nuclei and (vi extensive degeneration of the cells. The results obtained have been discussed with respect to the vacuolar/autolytic type of plant-specific AL-PCD.

  17. Haemophilia A and cardiovascular morbidity in a female SHAM syndrome carrier due to skewed X chromosome inactivation.

    Science.gov (United States)

    Janczar, Szymon; Kosinska, Joanna; Ploski, Rafal; Pastorczak, Agata; Wegner, Olga; Zalewska-Szewczyk, Beata; Paige, Adam J W; Borowiec, Maciej; Mlynarski, Wojciech

    2016-01-01

    We have recently described a severe haemophilia A and moyamoya (SHAM) syndrome caused by Xq28 deletions encompassing F8 and the BRCC3 familial moyamoya gene. The phenotype includes haemophilia A, moyamoya angiopathy, dysmorphia and hypertension. The genetic analysis of the family of our SHAM patient demonstrated carrier state in proband's mother and sister. The patient's mother is apparently well, whereas his currently 18-years-old sister presents with mild haemophilia A, coarctation of the aorta, hypertension, and ventricular arrhythmia. We performed X chromosome inactivation assay based on HpaII methylation analysis of a polymorphic short tandem repeat (STR) in the X linked AR (androgen receptor) gene and used quantitative real-time RT PCR to measure the expression of genes from the deleted region in proband's family members. We found an extremely skewed X chromosome inactivation pattern in the female members of the family leading to preferential inactivation of the X chromosome without Xq28 deletion in patient's sister. We demonstrated differential expression of the genes from the deleted region in four members of the family, that tightly correlates with the clinical features. In conclusion, we show that the haematologic and cardiovascular morbidity and the discrepancy between patient's sister and mother despite the same genetic lesion are due to skewed X chromosome inactivation leading to clinically relevant differential expression of SHAM syndrome genes. This report highlights the role for BRCC3 in cardiovascular physiology and disease, and demonstrates that in some complex hereditary syndromes full diagnostics may require the examination of both genetic and epigenetic events. PMID:26691666

  18. Reciprocal white matter alterations due to 16p11.2 chromosomal deletions versus duplications.

    Science.gov (United States)

    Chang, Yi Shin; Owen, Julia P; Pojman, Nicholas J; Thieu, Tony; Bukshpun, Polina; Wakahiro, Mari L J; Marco, Elysa J; Berman, Jeffrey I; Spiro, John E; Chung, Wendy K; Buckner, Randy L; Roberts, Timothy P L; Nagarajan, Srikantan S; Sherr, Elliott H; Mukherjee, Pratik

    2016-08-01

    Copy number variants at the 16p11.2 chromosomal locus are associated with several neuropsychiatric disorders, including autism, schizophrenia, bipolar disorder, attention-deficit hyperactivity disorder, and speech and language disorders. A gene dosage dependence has been suggested, with 16p11.2 deletion carriers demonstrating higher body mass index and head circumference, and 16p11.2 duplication carriers demonstrating lower body mass index and head circumference. Here, we use diffusion tensor imaging to elucidate this reciprocal relationship in white matter organization, showing widespread increases of fractional anisotropy throughout the supratentorial white matter in pediatric deletion carriers and, in contrast, extensive decreases of white matter fractional anisotropy in pediatric and adult duplication carriers. We find associations of these white matter alterations with cognitive and behavioral impairments. We further demonstrate the value of imaging metrics for characterizing the copy number variant phenotype by employing linear discriminant analysis to predict the gene dosage status of the study subjects. These results show an effect of 16p11.2 gene dosage on white matter microstructure, and further suggest that opposite changes in diffusion tensor imaging metrics can lead to similar cognitive and behavioral deficits. Given the large effect sizes found in this study, our results support the view that specific genetic variations are more strongly associated with specific brain alterations than are shared neuropsychiatric diagnoses. Hum Brain Mapp 37:2833-2848, 2016. © 2016 Wiley Periodicals, Inc. PMID:27219475

  19. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    OpenAIRE

    Geísa Pinheiro Paes; José Marcelo Soriano Viana; Fabyano Fonseca e Silva; Gabriel Borges Mundim

    2016-01-01

    Abstract The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kerne...

  20. Cryptic t(4;11) encoding MLL-AF4 due to insertion of 5' MLL sequences in chromosome 4

    NARCIS (Netherlands)

    von Bergh, A; Gargallo, P; De Prijck, B; Vranckx, H; Marschalek, R; Larripa, I; Kluin, P; Schuuring, E; Hagemeijer, A

    2001-01-01

    The t(4;11) translocation is the cytogenetic hallmark of a subset of acute lymphoblastic leukemias characterized by pro-B immunophenotype and a dismal prognosis. This translocation fuses the MLL gene on chromosome band 11q23 and the AF4 gene on 4q21, resulting in the expression of fusion transcripts

  1. Down syndrome due to a recombination of a chromosome 21 paracentric inversion in 1 of 2 cases with a review of paracentric recombinants

    Energy Technology Data Exchange (ETDEWEB)

    Jewett, T.; Rao, P.N.; Berry, M. [Wake Forest Univ., Winston-Salem, NC (United States)] [and others

    1994-09-01

    We recently identified 2 paracentric inversions (PAI) of chromosome 21. Case 1 was identified prenatally and paternally inherited: 46,XY,inv(21)(q21.2q22.13). The outcome is pending. Case 2 was a newborn male infant with clinical features of Down syndrome and an apparent inversion-duplication within chromosome 21. Parental chromosome analysis showed a maternal PAI: 46,XX,inv(21)(q21.2q22.3). The resulting child`s karyotype was: 46,XY,rec(21)(pter{yields}q21.2::q22.3{yields}q21.2::q22.3{yields}pter). Duplication of chromosome region q22.3{yields}qter was confirmed by FISH using a Down syndrome region specific probe (Cambio). Cytologically, the cornerstone of meiotic recombination from a paracentric inversion is the {open_quotes}reverse loop{close_quotes} model. In this model, a crossover event in the inversion loop results in the formation of gametes carrying either a dicentric chromatid, an acentric fragment, a normal chromatid or a chromatid with an inversion. However, a literature review of 326 PAI identified only 2 dicentrics and 15 other recombinants: 1 duplication/deletion; 6 deletions; 8 duplications. A U-type exchange model during meiosis within the inversion loop may best account for duplication/deletion recombinants. In contrast, the recombination in our case 2 would have occurred outside the loop. It is possible that no single explanation for PAI recombination may account for all outcomes. Alternative models of PAI recominational events will be presented. The literature suggests a low risk for prenatal loss due to abnormal PAI recombinants. In our review, viable offspring with recombinant chromosomes occurred in 3.8% of the PAI. Considering the potential for an increased incidence of recombination, prenatal diagnosis for all PAI carriers is warranted.

  2. Fragmentation and desorption from condensed alcohols due to soft X-rays: relevance to solid state astrochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, G.C.; Rocco, M.L.M.; Boechat-Roberty, H.M.; Nazareth, A.M.; Amaral, L. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Andrade, D.P.P.; Bergantini, A. [Universidade do Vale do Paraiba (UNIVAP), Sao Jose dos Campos, SP (Brazil)

    2012-07-01

    Full text: Methanol and ethanol, the simplest organic alcohols, are important precursors of more complex prebiotic species and are found abundantly in icy mantles on interstellar and protostellar dust. These molecules have been detected through infrared spectroscopy in some low- and high-mass protostars, such as W33A and RAFGL 7009, and also in comets, as Hale-Bopp and other Solar system bodies, such as the Centaur 5145 Pholus grains. All of these astronomical environments are subjected to some kind of ionizing agents, such as cosmic rays, electrons and photons (e.g. stellar radiation field). The aim of this work is to experimentally study the ionization, dissociation and ion desorption processes induced by photons and electrons on alcohols, CH{sub 3}OH and CH{sub 3}CH{sub 2}OH, as part of a systematic experimental study of condensed (ice phase) prebiotic molecules. We have employed soft X-ray photons at the oxygen K edge and variable electron energies to simulate the effects of stellar radiation field on the astrophysics ices. These results were also compared with effects produced by charged particles from cosmic rays. Ion photodesorption experiments on the icy surface were carried out at the Brazilian Synchrotron Light Source (LNLS), using the Spherical Grating Monochromator (SGM) beam line, operated in the single-bunch mode of the storage ring, with a period of 311 ns and bunch width of 60ps. Several fragments such as CH{sub 2}{sup +}, O{sup +}, H{sup +} and H{sub 3}{sup +} have been identified and their desorption rates per impact were determined and compared with previous results obtained using different ionization agents, such as electrons, heavy ions and photons at different energies in order to provide data to astrochemical models. (author)

  3. Fragmentation and desorption from condensed alcohols due to soft X-rays: relevance to solid state astrochemistry

    International Nuclear Information System (INIS)

    Full text: Methanol and ethanol, the simplest organic alcohols, are important precursors of more complex prebiotic species and are found abundantly in icy mantles on interstellar and protostellar dust. These molecules have been detected through infrared spectroscopy in some low- and high-mass protostars, such as W33A and RAFGL 7009, and also in comets, as Hale-Bopp and other Solar system bodies, such as the Centaur 5145 Pholus grains. All of these astronomical environments are subjected to some kind of ionizing agents, such as cosmic rays, electrons and photons (e.g. stellar radiation field). The aim of this work is to experimentally study the ionization, dissociation and ion desorption processes induced by photons and electrons on alcohols, CH3OH and CH3CH2OH, as part of a systematic experimental study of condensed (ice phase) prebiotic molecules. We have employed soft X-ray photons at the oxygen K edge and variable electron energies to simulate the effects of stellar radiation field on the astrophysics ices. These results were also compared with effects produced by charged particles from cosmic rays. Ion photodesorption experiments on the icy surface were carried out at the Brazilian Synchrotron Light Source (LNLS), using the Spherical Grating Monochromator (SGM) beam line, operated in the single-bunch mode of the storage ring, with a period of 311 ns and bunch width of 60ps. Several fragments such as CH2+, O+, H+ and H3+ have been identified and their desorption rates per impact were determined and compared with previous results obtained using different ionization agents, such as electrons, heavy ions and photons at different energies in order to provide data to astrochemical models. (author)

  4. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    Directory of Open Access Journals (Sweden)

    Geísa Pinheiro Paes

    2016-03-01

    Full Text Available Abstract The objectives of this study were to assess linkage disequilibrium (LD and selection-induced changes in single nucleotide polymorphism (SNP frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D, the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis.

  5. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    Science.gov (United States)

    Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca e; Mundim, Gabriel Borges

    2016-01-01

    Abstract The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903

  6. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits.

    Science.gov (United States)

    Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca E; Mundim, Gabriel Borges

    2016-03-01

    The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903

  7. Tetrasomy 13q31.1qter due to an inverted duplicated neocentric marker chromosome in a fetus with multiple malformations.

    Science.gov (United States)

    Haddad, Véronique; Aboura, Azzedine; Tosca, Lucie; Guediche, Narjes; Mas, Anne-Elisabeth; L'Herminé, Aurore Coulomb; Druart, Luc; Picone, Olivier; Brisset, Sophie; Tachdjian, Gérard

    2012-04-01

    Small supernumerary marker chromosome (sSMC) lacking alpha satellite DNA or endogenous centromere regions are rare and contain fully functional centromeres, called neocentromeres. We report on a woman with a 14-week gestation pregnancy with a cystic hygroma and cerebellar hypoplasia at ultrasound examination. Cytogenetic studies showed a karyotype 47,XY,+mar dn. This sSMC was observed in chorionic villi, lung, and muscle tissue. Array Comparative Genomic Hybridization showed a gain from 13q31.1 to 13qter region. Fluorescent in situ hybridization with pan alpha satellite probe and probes specific for chromosome 13 showed a marker corresponding to an inversion duplication of the 13q distal chromosomal region without alpha satellite DNA sequence, suggesting the presence of a neocentromere. Examination of the fetus showed dysmorphic features, cystic cervical hygroma, postaxial polydactyly of the right hand and left foot with short fingers, malrotation of the gut, and a micropenis with hypospadias. Genotype-phenotype correlation in tetrasomy 13q is discussed according to the four 13q chromosomal breakpoints reported (13q32, 13q31, 13q21, 13q14) for chromosome 13 supernumerary markers.

  8. Ultrastructural characterization of the sex chromosomes during spermatogenesis of spiders having holocentric chromosomes and a long diffuse stage.

    Science.gov (United States)

    Benavente, R; Wettstein, R

    1980-01-01

    An ultrastructural study has been made of spermatogenesis in two species of primitive spiders having holocentric chromosomes (Dysdera crocata, male X0 and Sergestria florentia X1X2O). Analysis of the meiotic prophase shows a scarcity or absence of typical leptotene to pachytene stages. Only in D. crocata have synaptonemal complex (SC) remnants been seen, and these occurred in nuclei with an extreme chromatin decondensation. In both species typical early prophase stages have been replaced by nuclei lacking SC and with their chromatin almost completely decondensed, constituting a long and well-defined diffuse stage. Only nucleoli and the condensed sex chromosomes can be identified. - In S. florentina paired non-homologous sex chromosomes lack a junction lamina and thus clearly differ from the sex chromosomes of more evolved spiders with an X1X20 male sex determination mechanism. In the same species, sex chromosomes can be recognized during metaphase I due to their special structural details, while in D. crocata the X chromosome is not distinguishable from the autosomes at this stage. - The diffuse stage and particularly the structural characteristics of the sex chromosomes during meiotic prophase are reviewed and discussed in relation to the meiotic process in other arachnid goups. PMID:7371451

  9. Preventing freezing of condensate inside tubes of air cooled condenser

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Jeong A; Hwang, In Hwan; Lee, Dong Hwan [Chonbuk Nat' l Univ., Jeonju (Korea, Republic of); Cho, Young Il [Drexel Univ., Philadelphia (United States)

    2012-08-15

    An air cooled condenser is a device that is used for converting steam into condensate by using ambient air. The air cooled condenser is prone to suffer from a serious explosion when the condensate inside the tubes of a heat exchanger is frozen; in particular, tubes can break during winter. This is primarily due to the structural problem of the tube outlet of an existing conventional air cooled condenser system, which causes the backflow of residual steam and noncondensable gases. To solve the backflow problem in such condensers, such a system was simulated and a new system was designed and evaluated in this study. The experimental results using the simulated condenser showed the occurrence of freezing because of the backflow inside the tube. On the other hand, no backflow and freezing occurred in the advanced new condenser, and efficient heat exchange occurred.

  10. Highly distinct chromosomal structures in cowpea (Vigna unguiculata), as revealed by molecular cytogenetic analysis.

    Science.gov (United States)

    Iwata-Otsubo, Aiko; Lin, Jer-Young; Gill, Navdeep; Jackson, Scott A

    2016-05-01

    Cowpea (Vigna unguiculata (L.) Walp) is an important legume, particularly in developing countries. However, little is known about its genome or chromosome structure. We used molecular cytogenetics to characterize the structure of pachytene chromosomes to advance our knowledge of chromosome and genome organization of cowpea. Our data showed that cowpea has highly distinct chromosomal structures that are cytologically visible as brightly DAPI-stained heterochromatic regions. Analysis of the repetitive fraction of the cowpea genome present at centromeric and pericentromeric regions confirmed that two retrotransposons are major components of pericentromeric regions and that a 455-bp tandem repeat is found at seven out of 11 centromere pairs in cowpea. These repeats likely evolved after the divergence of cowpea from common bean and form chromosomal structure unique to cowpea. The integration of cowpea genetic and physical chromosome maps reveals potential regions of suppressed recombination due to condensed heterochromatin and a lack of pairing in a few chromosomal termini. This study provides fundamental knowledge on cowpea chromosome structure and molecular cytogenetics tools for further chromosome studies. PMID:26758200

  11. Water Condensation

    DEFF Research Database (Denmark)

    Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund;

    2014-01-01

    The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics......, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address...

  12. [Chromosomal organization of the genomes of small-chromosome plants].

    Science.gov (United States)

    Muravenko, O V; Zelenin, A V

    2009-11-01

    An effective approach to study the chromosome organization in genomes of plants with small chromosomes and/or with low-informative C-banding patterns was developed in the course of investigation of the karyotypes of cotton plant, camomile, flax, and pea. To increase the resolving power of chromosome analysis, methods were worked out for revealing early replication patterns on chromosomes and for artificial impairment of mitotic chromosome condensation with the use of a DNA intercalator, 9-aminoacridine (9-AMA). To estimate polymorphism of the patterns of C-banding of small chromosomes on preparations obtained with the use of 9-AMA, it is necessary to choose a length interval that must not exceed three average sizes of metaphase chromosomes without the intercalator. The use of 9-AMA increases the resolution of differential C- and OR-banding and the precision of physical chromosome mapping by the FISH method. Of particular importance in studying small chromosomes is optimization of the computer-aided methods used to obtain and process chromosome images. The complex approach developed for analysis of the chromosome organization in plant genomes was used to study the karyotypes of 24 species of the genus Linum L. It permitted their chromosomes to be identified for the first time, and, in addition, B chromosomes were discovered and studied in the karyotypes of the species of the section Syllinum. By similarity of the karyotypes, the studied flax species were distributed in eight groups in agreement with the clusterization of these species according to the results of RAPD analysis performed in parallel. Systematic positions and phylogenetic relationships of the studied flax species were verified. Out results can serve as an important argument in favour of the proposal to develop a special program for sequencing the genome of cultivated flax (L. usitatissimum L.), which is a major representative of small-chromosome species. PMID:20058798

  13. Tetrasomy 3q26.32-q29 due to a supernumerary marker chromosome in a child with pigmentary mosaicism of Ito.

    Science.gov (United States)

    Cunha, Karina S; Simioni, Milena; Vieira, Tarsis P; Gil-da-Silva-Lopes, Vera L; Puzzi, Maria B; Steiner, Carlos E

    2016-03-01

    Pigmentary mosaicism of Ito (PMI) is a skin abnormality often characterized by hypopigmentation of skin, following, in most cases, the Blaschko lines, usually associated with extracutaneous abnormalities, especially abnormalities of the central nervous system (CNS). It is suggested that this pattern arises from the presence and migration of two cell lineages in the ectoderm layer during the embryonic period and embryonic cell migration, with different gene expression profiles associated with pigmentation. Several types of chromosomal aberrations, with or without mosaicism, have been associated with this disorder. This study comprised clinical description and cytogenetic analysis of a child with PMI. The G-banded karyotype analysis revealed a supernumerary marker chromosome in 76% of the analyzed metaphases from peripheral blood lymphocytes. Array genomic hybridization analysis showed a copy number gain between 3q26.32-3q29, of approximately 20.5 Mb. Karyotype was defined as 47,XX,+mar[38]/46,XX[12].arr 3q26.32-3q29(177,682,859- 198,043,720)x4 dn. Genes mapped in the overlapping region among this patient and three other cases described prior to this study were listed and their possible involvement on PMI pathogenesis is discussed. PMID:27007896

  14. Condensate - undervalued

    International Nuclear Information System (INIS)

    A recent study of resource exploitation in the Middle East, Asia, Australia and New Zealand is reported, which shows that the economics of many gas fields could be enhanced by exploiting their gas condensate resources. Condensates, a range of gas-derived liquids heavier than Liquefied Petroleum Gas, are, as yet, under-exploited. The author argues that these valuable resources should be exploited to the benefit of the industry and the consumer, though some technological difficulties still need to be overcome. (UK)

  15. Duplication of the segment q12.2 leads to qter of chromosome 22 due to paternal inversion 22(p13q12.2).

    Science.gov (United States)

    Fujimoto, A; Wilson, M G; Towner, J W

    1983-01-01

    A 1730-g male infant, born at 37 weeks gestation, had multiple congenital anomalies, consisting of microcephaly, hypertelorism, bilateral cleft lip and palate, micrognathia, low-set ears, and cryptorchidism. Chromosome analysis showed a recombinant 22 derived from the paternal inversion (22)(p13q12.2). The proband's karyotype is 46,XY,rec(22),dup q,inv(22)(p13q12.2)pat, which has a duplication of q12.2 leads to qter. An identical recombinant has been reported in a female infant in Mexico whose mother was a carrier of the inversion. Similar congenital anomalies present in these two patients demonstrate the phenotype of duplication of the distal long arm 22. This report also documents the occurrence of an identical inversion in two apparently unrelated Mexican families.

  16. Bias in peak clad temperature predictions due to uncertainties in modeling of ECC bypass and dissolved non-condensable gas phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Rohatgi, U.S.; Neymotin, L.Y.; Jo, J.; Wulff, W. (Brookhaven National Lab., Upton, NY (USA))

    1990-09-01

    This report describes a general method for estimating the effect on the Reflood Phase PCT from systematic errors (biases) associated with the modelling of the ECCS and dissolved nitrogen, and the application of this method in estimating biases in the Reflood Phase PCT (second PCT) predicted by the TRAC/PF1/MOD1, Version 14.3. The bias in the second PCT due to the uncertainty in the existing code models for ECCS related phenomena is {minus}19{degree}K ({minus}34{degree}F). The negative bias implies that the code models for this phenomena are conservative. The bias in the second PCT due to the lack of modelling of dissolved N{sub 2} in the code is estimated to be 9.9{degree}K (17.8{degree}F). The positive bias implies that the absence of dissolved N{sub 2} model makes the code prediction of PCT non-conservative. The bias estimation in this report is a major exception among all other uncertainty and bias assessments performed in conjunction with the CSAU methodology demonstration, because this bias estimation benefitted from using full-scale test data from the full-scale Upper Plenum Test Facility (UPTF). Thus, the bias estimates presented here are unaffected by scale distortions in test facilities. Data from small size facilities were also available and an estimate of bias based on these data will be conservative. 35 refs., 18 figs., 5 tabs.

  17. Altered metaphase chromosome structure in xrs-5 cells is not related to its radiation sensitivity or defective DNA break rejoining

    International Nuclear Information System (INIS)

    The Chinese hamster ovary (CHO) cell line xrs-5 is a radiation-sensitive derivative of CHO-K1 cells. The xrs-5 cells have a defect in DNA double-strand break rejoining and show alterations in chromosome structure and nuclear morphology. The relationship between radiation sensitivity and metaphase chromosome morphology was examined in 12 'revertant' xrs-5 clones isolated following treatment with 5-azacytidine. Nine of the clones were radioresistant while the other three retained xrs-5-like radiation sensitivity. Chromosome morphology reverted to CHO-K1-like characteristics in three of the radioresistant clones and one of the radiosensitive clones suggesting that the over-condensed metaphase chromosome morphology of xrs-5 cells does not underlie its radiation sensitivity. Radiation sensitivity did correlate with DNA double-strand break rejoining ability. The radioresistant clones showing the over-condensed xrs-5-like chromosome morphology were also slightly more sensitive to the topoisomerase II inhibitor etoposide (VP-16) than CHO-K1, suggesting that the over-condensed morphology might be due to alterations in the phosphorylation of chromatin proteins

  18. Telomere dysfunction and chromosome instability

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, John P., E-mail: jmurnane@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, 2340 Sutter Street, San Francisco, CA 94143-1331 (United States)

    2012-02-01

    The ends of chromosomes are composed of a short repeat sequence and associated proteins that together form a cap, called a telomere, that keeps the ends from appearing as double-strand breaks (DSBs) and prevents chromosome fusion. The loss of telomeric repeat sequences or deficiencies in telomeric proteins can result in chromosome fusion and lead to chromosome instability. The similarity between chromosome rearrangements resulting from telomere loss and those found in cancer cells implicates telomere loss as an important mechanism for the chromosome instability contributing to human cancer. Telomere loss in cancer cells can occur through gradual shortening due to insufficient telomerase, the protein that maintains telomeres. However, cancer cells often have a high rate of spontaneous telomere loss despite the expression of telomerase, which has been proposed to result from a combination of oncogene-mediated replication stress and a deficiency in DSB repair in telomeric regions. Chromosome fusion in mammalian cells primarily involves nonhomologous end joining (NHEJ), which is the major form of DSB repair. Chromosome fusion initiates chromosome instability involving breakage-fusion-bridge (B/F/B) cycles, in which dicentric chromosomes form bridges and break as the cell attempts to divide, repeating the process in subsequent cell cycles. Fusion between sister chromatids results in large inverted repeats on the end of the chromosome, which amplify further following additional B/F/B cycles. B/F/B cycles continue until the chromosome acquires a new telomere, most often by translocation of the end of another chromosome. The instability is not confined to a chromosome that loses its telomere, because the instability is transferred to the chromosome donating a translocation. Moreover, the amplified regions are unstable and form extrachromosomal DNA that can reintegrate at new locations. Knowledge concerning the factors promoting telomere loss and its consequences is

  19. X-Chromosome dosage compensation.

    Science.gov (United States)

    Meyer, Barbara J

    2005-01-01

    In mammals, flies, and worms, sex is determined by distinctive regulatory mechanisms that cause males (XO or XY) and females (XX) to differ in their dose of X chromosomes. In each species, an essential X chromosome-wide process called dosage compensation ensures that somatic cells of either sex express equal levels of X-linked gene products. The strategies used to achieve dosage compensation are diverse, but in all cases, specialized complexes are targeted specifically to the X chromosome(s) of only one sex to regulate transcript levels. In C. elegans, this sex-specific targeting of the dosage compensation complex (DCC) is controlled by the same developmental signal that establishes sex, the ratio of X chromosomes to sets of autosomes (X:A signal). Molecular components of this chromosome counting process have been defined. Following a common step of regulation, sex determination and dosage compensation are controlled by distinct genetic pathways. C. elegans dosage compensation is implemented by a protein complex that binds both X chromosomes of hermaphrodites to reduce transcript levels by one-half. The dosage compensation complex resembles the conserved 13S condensin complex required for both mitotic and meiotic chromosome resolution and condensation, implying the recruitment of ancient proteins to the new task of regulating gene expression. Within each C. elegans somatic cell, one of the DCC components also participates in the separate mitotic/meiotic condensin complex. Other DCC components play pivotal roles in regulating the number and distribution of crossovers during meiosis. The strategy by which C. elegans X chromosomes attract the condensin-like DCC is known. Small, well-dispersed X-recognition elements act as entry sites to recruit the dosage compensation complex and to nucleate spreading of the complex to X regions that lack recruitment sites. In this manner, a repressed chromatin state is spread in cis over short or long distances, thus establishing the

  20. Male-biased aganglionic megacolon in the TashT mouse line due to perturbation of silencer elements in a large gene desert of chromosome 10.

    Directory of Open Access Journals (Sweden)

    Karl-F Bergeron

    2015-03-01

    Full Text Available Neural crest cells (NCC are a transient migratory cell population that generates diverse cell types such as neurons and glia of the enteric nervous system (ENS. Via an insertional mutation screen for loci affecting NCC development in mice, we identified one line-named TashT-that displays a partially penetrant aganglionic megacolon phenotype in a strong male-biased manner. Interestingly, this phenotype is highly reminiscent of human Hirschsprung's disease, a neurocristopathy with a still unexplained male sex bias. In contrast to the megacolon phenotype, colonic aganglionosis is almost fully penetrant in homozygous TashT animals. The sex bias in megacolon expressivity can be explained by the fact that the male ENS ends, on average, around a "tipping point" of minimal colonic ganglionosis while the female ENS ends, on average, just beyond it. Detailed analysis of embryonic intestines revealed that aganglionosis in homozygous TashT animals is due to slower migration of enteric NCC. The TashT insertional mutation is localized in a gene desert containing multiple highly conserved elements that exhibit repressive activity in reporter assays. RNAseq analyses and 3C assays revealed that the TashT insertion results, at least in part, in NCC-specific relief of repression of the uncharacterized gene Fam162b; an outcome independently confirmed via transient transgenesis. The transcriptional signature of enteric NCC from homozygous TashT embryos is also characterized by the deregulation of genes encoding members of the most important signaling pathways for ENS formation-Gdnf/Ret and Edn3/Ednrb-and, intriguingly, the downregulation of specific subsets of X-linked genes. In conclusion, this study not only allowed the identification of Fam162b coding and regulatory sequences as novel candidate loci for Hirschsprung's disease but also provides important new insights into its male sex bias.

  1. TheArabidopsis CDM1 gene plays an important role in regulating meiotic chromosome condensation%拟南芥CDM1基因在减数分裂染色体浓缩过程中起重要作用

    Institute of Scientific and Technical Information of China (English)

    龙海飞; 张智敏; 陆平利

    2016-01-01

    减数分裂是高等生物有性生殖中的一个重要环节,其精确调控的染色体相互作用和动态变化是形成功能配子所必需的。前期的研究表明, CDM1在拟南芥小孢子形成中起重要作用,但还不清楚它是否也参与减数分裂。本研究利用DAPI染色和着丝粒探针荧光标记原位杂交(FISH)比较分析了野生型和cdm1突变体减数分裂过程中染色体的动态变化。结果显示,与野生型相比, cdm1同源染色体配对不受影响,但在减数分裂II时期, cdm1染色体的浓缩程度出现一定程度的异常,不能形成与野生型中相同的染色体结构。此外, qRT-PCR分析显示,减数分裂相关基因MS5、MMD1、AML2、AtZIP4和AtMSH4在cdm14~7期(减数分裂时期)花药中的表达显著降低。因此推测, CDM1可能是通过影响与减数分裂相关基因的表达参与调控拟南芥减数分裂中的染色体浓缩和去浓缩过程。%Meiosis is one of critical processes for sexual reproduction in eukaryotic organisms. During meiosis, functional gamete formation relies on accurate regulation of homologous chromosome interaction and dynamic movements. Previous study showed that theCDM1 gene is required for microspore development inArabidop-sis. However, so far, it is still unknown whetherCDM1 is also involved in meiosis. In this study, meiotic chro-mosome spread with DAPI staining and centromere-probe labeled FISH were utilized to investigate meiotic chromosome dynamic movement in wild-type andcdm1 cells. The results showed that meiotic homologous chromosome paring in cdm1 is not affected. However, during meiosis II, chromosome condensation incdm1 was detected abnormal, rarely forming similar chromosome structures as observed in wild-type. In addition, qRT-PCR analysis discovered that the expression of several meiosis-related genes, includingMS5,MMD1, AML2,AtZIP4andAtMSH4, was greatly decreased incdm1 stage 4–7 anthers, in which meiosis

  2. Chromosome therapy. Correction of large chromosomal aberrations by inducing ring chromosomes in induced pluripotent stem cells (iPSCs).

    Science.gov (United States)

    Kim, Taehyun; Bershteyn, Marina; Wynshaw-Boris, Anthony

    2014-01-01

    The fusion of the short (p) and long (q) arms of a chromosome is referred to as a "ring chromosome." Ring chromosome disorders occur in approximately 1 in 50,000-100,000 patients. Ring chromosomes can result in birth defects, mental disabilities, and growth retardation if additional genes are deleted during the formation of the ring. Due to the severity of these large-scale aberrations affecting multiple contiguous genes, no possible therapeutic strategies for ring chromosome disorders have so far been proposed. Our recent study (Bershteyn et al.) using patient-derived fibroblast lines containing ring chromosomes, found that cellular reprogramming of these fibroblasts into induced pluripotent stem cells (iPSCs) resulted in the cell-autonomous correction of the ring chromosomal aberration via compensatory uniparental disomy (UPD). These observations have important implications for studying the mechanism of chromosomal number control and may lead to the development of effective therapies for other, more common, chromosomal aberrations.

  3. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH SPERM DISORDERS

    OpenAIRE

    L. Y. Pylyp; L. A. Spinenko; V. D. Zukin; N. M. Bilko

    2013-01-01

    Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intrac...

  4. Condensation heat transfer

    Science.gov (United States)

    Rose, J. W.

    The paper gives a brief description of some of the better understood aspects of condensation heat transfer and includes discussion of the liquid-vapour interface, natural and forced convection laminar film condensation and dropwise condensation.

  5. ADN et chromosomes

    OpenAIRE

    Hayes, Hélène

    2000-01-01

    Chaque chromosome contient une seule molécule d’ADN. L’ADN déroulé d’un noyau de cellule humaine mesurerait environ 1,8 m : chaque molécule d’ADN est enroulée et compactée en plusieurs étapes, grâce à l’association de différentes protéines, et loge dans le noyau de 6 µm de diamètre. Le degré de condensation de l’ADN est variable selon les régions chromosomiques et les régions les moins condensées sont les plus riches en gènes. L’ADN est composé d’une variété de séquences codantes ou non et ré...

  6. Condensin-mediated chromosome organization and gene regulation

    Directory of Open Access Journals (Sweden)

    Alyssa Christine Lau

    2015-01-01

    Full Text Available In many organisms sexual fate is determined by a chromosome-based method which entails a difference in sex chromosome-linked gene dosage. Consequently, a gene regulatory mechanism called dosage compensation equalizes X-linked gene expression between the sexes. Dosage compensation initiates as cells transition from pluripotency to differentiation. In C. elegans, dosage compensation is achieved by the dosage compensation complex (DCC binding to both X chromosomes in hermaphrodites to downregulate gene expression by two fold. The DCC contains a subcomplex (condensin IDC similar to the evolutionarily conserved condensin complexes which play a fundamental role in chromosome dynamics during mitosis. Therefore, mechanisms related to mitotic chromosome condensation are hypothesized to mediate dosage compensation. Consistent with this hypothesis, monomethylation of histone H4 lysine 20 (H4K20 is increased, whereas acetylation of histone H4 lysine 16 (H4K16 is decreased, both on mitotic chromosomes and on interphase dosage compensated X chromosomes in worms. These observations suggest that interphase dosage compensated X chromosomes maintain some characteristics associated with condensed mitotic chromosome. This chromosome state is stably propagated from one cell generation to the next. In this review we will speculate on how the biochemical activities of condensin can achieve both mitotic chromosome compaction and gene repression.

  7. Monopole condensation and confinement

    International Nuclear Information System (INIS)

    To understand the mechanism of confinement is important in order to explain hadron physics out of QCD. After the abelian projection, QCD can be regarded as an abelian theory with electric charges and monopoles. If the monopoles make Bose condensation, charged quarks and gluons are confined due to the dual Meissner effect. Monte Carlo simulation was performed to test whether the conjecture is true or not at least on lattices. The results in 1995 were reported in three papers. In three topics of monopole dynamics in abelian projected QCD, the detailed analysis of SU(2) monopole action obtained after the block-spin transformation on the dual lattice, the results of SU(3) monopole action and the new gauges showing abelian and monopole dominances are reported. In monopole condensation and Polyakov loop in finite-temperature pure QCD, the relation between the abelian monopole condensation and the deconfinement phase transition of the finite temperature pure QCD is reported, and the boundary conditions and the cases of SU(2) and SU(3) are described. In disorder parameter of confinement, the disorder parameter in SU(2) QCD and the numerical simulation in finite temperature SU(2) QCD are reported. (K.I.)

  8. Chromosome Microarray.

    Science.gov (United States)

    Anderson, Sharon

    2016-01-01

    Over the last half century, knowledge about genetics, genetic testing, and its complexity has flourished. Completion of the Human Genome Project provided a foundation upon which the accuracy of genetics, genomics, and integration of bioinformatics knowledge and testing has grown exponentially. What is lagging, however, are efforts to reach and engage nurses about this rapidly changing field. The purpose of this article is to familiarize nurses with several frequently ordered genetic tests including chromosomes and fluorescence in situ hybridization followed by a comprehensive review of chromosome microarray. It shares the complexity of microarray including how testing is performed and results analyzed. A case report demonstrates how this technology is applied in clinical practice and reveals benefits and limitations of this scientific and bioinformatics genetic technology. Clinical implications for maternal-child nurses across practice levels are discussed. PMID:27276104

  9. Effect of Non-Condensable Gas Mass Fraction on Condensation Heat Transfer for Water-Ethanol Vapor Mixture

    Science.gov (United States)

    Wang, Shixue; Utaka, Yoshio

    The condensation heat transfer characteristic curves for a ternary vapor mixture of water, ethanol and air (or nitrogen) under several ethanol concentrations and relatively low concentrations of air (or nitrogen) were measured. The effect of non-condensable gas on several different domains in the condensation curves was discussed. The effect of non-condensable gas in the domains controlled by the diffusion resistance and the filmwise condensation was not notable; whereas that in the domain dominated by the condensate resistance of dropwise mode was remarkable. Moreover, variations due to changes in non-condensable gas concentration of several characteristic points representing the curves were discussed.

  10. Phase contrast imaging of Bose condensed clouds

    NARCIS (Netherlands)

    Meppelink, R; Rozendaal, R.A.; Koller, S.B.; Vogels, J.M.; van der Straten, P.

    2010-01-01

    Phase contrast imaging is used to observe Bose-Einstein condensates (BECs) at finite temperature in situ. The imaging technique is used to accurately derive the absolute phase shift of a probe laser beam due to both the condensate and the thermal cloud. The accuracy of the method is enhanced by usin

  11. Meiotic chromosomal variation resulting from irradiation of pollen in maize

    International Nuclear Information System (INIS)

    The objective of this study was to standardize an induction strategy of chromosome aberrations in maize inbred line L-869. Pollen grains irradiated with 0, 36 and 72 Gy were used for fertilization. Resulting seeds were planted in a greenhouse to assess the number of abnormal meiotic cells. Germination, height, sterility and mortality were verified. Cells with delayed separation of chromosomes, translocation, deficiency, abnormal pairing, later condensation and anaphase bridges were observed. The number of abnormalities increased as the dosage increased but chromosome aberration types were the same regardless of the dosages used. Various chromosome-altered plants were obtained without viability loss. (author)

  12. Chromosomes of Protists: The crucible of evolution.

    Science.gov (United States)

    Soyer-Gobillard, Marie-Odile; Dolan, Michael F

    2015-12-01

    As early as 1925, the great protozoologist Edouard Chatton classified microorganisms into two categories, the prokaryotic and the eukaryotic microbes, based on light microscopical observation of their nuclear organization. Now, by means of transmission electron microscopy, we know that prokaryotic microbes are characterized by the absence of nuclear envelope surrounding the bacterial chromosome, which is more or less condensed and whose chromatin is deprived of histone proteins but presents specific basic proteins. Eukaryotic microbes, the protists, have nuclei surrounded by a nuclear envelope and have chromosomes more or less condensed, with chromatin-containing histone proteins organized into nucleosomes. The extraordinary diversity of mitotic systems presented by the 36 phyla of protists (according to Margulis et al., Handbook of Protoctista, 1990) is in contrast to the relative homogeneity of their chromosome structure and chromatin components. Dinoflagellates are the exception to this pattern. The phylum is composed of around 2000 species, and characterized by unique features including their nucleus (dinokaryon), dinomitosis, chromosome organization and chromatin composition. Although their DNA synthesis is typically eukaryotic, dinoflagellates are the only eukaryotes in which the chromatin, organized into quasi-permanently condensed chromosomes, is in some species devoid of histones and nucleosomes. In these cases, their chromatin contains specific DNA-binding basic proteins. The permanent compaction of their chromosomes throughout the cell cycle raises the question of the modalities of their division and their transcription. Successful in vitro reconstitution of nucleosomes using dinoflagellate DNA and heterologous corn histones raises questions about dinoflagellate evolution and phylogeny. [Int Microbiol 18(4):209-216 (2015)]. PMID:27611673

  13. Condensation heat transfer on two-tier superhydrophobic surfaces

    Science.gov (United States)

    Cheng, Jiangtao; Vandadi, Aref; Chen, Chung-Lung

    2012-09-01

    We investigated water vapor condensation on a two-tier superhydrophobic surface in an environmental scanning electron microscope (ESEM) and in a customer-designed vapor chamber. We have observed continuous dropwise condensation (DWC) on the textured surface in ESEM. However, a film layer of condensate was formed on the multiscale texture in the vapor chamber. Due to the filmwise condensation, the condensation heat transfer coefficient of the superhydrophobic surface is lower than that of a flat hydrophobic surface especially under high heat flux situations. Our studies indicate that adaptive and prompt condensate droplet purging is the dominant factor for sustaining long-term DWC.

  14. Novel Gene Acquisition on Carnivore Y Chromosomes

    OpenAIRE

    Murphy, William J.; A J Pearks Wilkerson; Terje Raudsepp; Richa Agarwala; Schäffer, Alejandro A.; Roscoe Stanyon; Chowdhary, Bhanu P

    2006-01-01

    Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we...

  15. Studies on the mitotic chromosome scaffold of Allium sativum

    Institute of Scientific and Technical Information of China (English)

    ZHAOJIAN; SHAOBOJIN; 等

    1995-01-01

    An argentophilic structure is present in the metaphase chromosomes of garlic(Allium sativum),Cytochemical studies indicate that the main component of the structure is non-histone proteins(NHPs).The results of light and electron microscopic observations reveal that the chromosme NHP scaffold is a network which is composed of fibres and granules and distributed throughout the chromosomes.In the NHP network,there are many condensed regions that are connected by redlatively looser regions.The distribution of the condensed regions varies in individual chromosomes.In some of the chromosomes the condensed regions are lognitudinally situsted in the central part of a chromatid while in others these regions appear as coillike transverse bands.At early metaphase.scaffolds of the sister chromatids of a chromosome are linked to each other in the centromeric region,meanwhile,they are connected by scafold materials along the whole length of the chromosome.At late metaphase,however,the connective scaffold materials between the two sister chromatids disappear gradually and the chromatids begin to separate from one another at their ends.but the chromatids are linked together in the centromeric region until anaphase.This connection seems to be related to the special structure of the NHP scaffold formed in the centromeric region.The morphological features and dynamic changes of the chromosome scaffold are discussed.

  16. A Geometric Approach For Fully Automatic Chromosome Segmentation

    CERN Document Server

    Minaee, Shervin; Khalaj, Babak Hossein

    2011-01-01

    Chromosome segmentation is a fundamental task in human chromosome analysis. Most of previous methods for separation between touching chromosomes require human intervention. In this paper, a geometry based method is used for automatic chromosome segmentation. This method can be divided into two phases. In the first phase, chromosome clusters are detected using three geometric criteria and in the second phase chromosome clusters are separated using a proper cut line. However, most earlier methods do not work well with chromosome clusters that contain more than two chromosomes. Our method, on the other hand, has a high efficiency in separation of chromosome clusters in such scenarios. Another advantage of the proposed method is that it can easily apply to any type of images such as binary images. This is due to the fact that the proposed scheme uses the geometric features of chromosomes which are independent of the type of images. The performance of the proposed scheme is demonstrated on a database containing to...

  17. Condensation in insulated homes

    Energy Technology Data Exchange (ETDEWEB)

    Wiley, R A

    1978-05-28

    A research proposal on condensation in insulated homes is presented. Information is provided on: justification for condensation control; previous work and present outlook (good vapor barrier, condensation and retrofit insulation, vapor barrier decreases condensation, brick-veneer walls, condensation in stress-skin panels, air-conditioned buildings, retrofitting for conservation, study on mobile homes, high indoor relative humidity, report on various homes); and procedure (after funding has been secured). Measures are briefly described on opening walls, testing measures, and retrofitting procedures. An extensive bibliography and additional informative citations are included. (MCW)

  18. Modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Condensation occurs when vapor is cooled sufficiently below the saturation temperature to induce the nucleation of droplets. Such nucleation may occur homogeneously within the vapor or heterogeneously on entrained particular matter. Heterogeneous nucleation may occur on the walls of the system, where the temperature is below the saturation temperature. There are two forms of heterogeneous condensation, drop-wise and film-wise. Another form of condensation occurs when vapor directly contacts to subcooled liquid. In nuclear power plant systems, all forms of condensation may occur during normal operation or accident conditions. In this work the modelling of condensation is surveyed, including the Nusselts' laminar film condensation theory in 1916, Rohsenow's turbulent film condensation model in 1950s, and Chen's models in 1987. Major attention is paid on the film condensation models among various research results because of its importance in engineering applications. It is found that theory, experiment, and empirical correlations for film condensation are well established, but research for drop-wise and direct-contact condensation are not sufficient yet. Condensation models in the best-estimate system codes such as RELAP5/MOD3 and CATHARE2 are also investigated. 3 tabs., 11 figs., 36 refs. (Author)

  19. Chromatin structure and ionizing-radiation-induced chromosome aberrations

    International Nuclear Information System (INIS)

    The possible influence of chromatic structure or activity on chromosomal radiosensitivity was studied. A cell line was isolated which contained some 105 copies of an amplified plasmid in a single large mosquito artificial chromosome (MAC). This chromosome was hypersensitive to DNase I. Its radiosensitivity was some three fold greater than normal mosquito chromosomes in the same cell. In cultured human cells irradiated during G0, the initial breakage frequency in chromosome 4, 19 and the euchromatic and heterochromatic portions of the Y chromosome were measured over a wide range of doses by inducing Premature Chromosome Condensation (PCC) immediately after irradiation with Cs-137 gamma rays. No evidence was seen that Y heterochromatin or large fragments of it remained unbroken. The only significant deviation from the expected initial breakage frequency per Gy per unit length of chromosome was that observed for the euchromatic portion of the Y chromosome, with breakage nearly twice that expected. The development of aberrations involving X and Y chromosomes at the first mitosis after irradation was also studied. Normal female cells sustained about twice the frequency of aberrations involving X chromosomes for a dose of 7.3 Gy than the corresponding male cells. Fibroblasts from individuals with supernumerary X chromosomes did not show any further increase in X aberrations for this dos. The frequency of aberrations involving the heterochromatic portion of the long arm of the Y chromosome was about what would be expected for a similar length of autosome, but the euchromatic portion of the Y was about 3 times more radiosensitive per unit length. 5-Azacytidine treatment of cultured human female fibroblasts or fibroblasts from a 49,XXXXY individual, reduced the methylation of cytosine residues in DNA, and resulted in an increased chromosomal radiosensitivity in general, but it did not increase the frequency of aberrations involving the X chromosomes

  20. Radiation induced chromosome instability in human fibroblasts

    International Nuclear Information System (INIS)

    Evidence has been arising that some biological effects can manifest many cell divisions after irradiation. We have demonstrated that de novo chromosome instability can be detected 10- 15 mean population doubling after heavy ion irradiations. This chromosome instability is characterized by end to end fusions between specific chromosomes. The specificity of the instability may differ from one donor to another but for the same donor, the same instability should be observed after irradiation, during the senescence process and after SV40 transfection (before crisis). In irradiated primary culture fibroblasts, the expression of the delayed chromosomal instability lasts for several cell divisions without inducing cell death. Several rounds of fusions- breakage-fusions can be performed and unbalanced clones emerge (gain or loss of chromosomes with the shorter telomeres would become unstable first.. The difference in the chromosomal instability among donors could be due to a polymorphism in telomere lengths. This could induce large variation in long term response to irradiation among individuals. (author)

  1. Multistep assembly of DNA condensation clusters by SMC.

    Science.gov (United States)

    Kim, HyeongJun; Loparo, Joseph J

    2016-01-01

    SMC (structural maintenance of chromosomes) family members play essential roles in chromosome condensation, sister chromatid cohesion and DNA repair. It remains unclear how SMCs structure chromosomes and how their mechanochemical cycle regulates their interactions with DNA. Here we used single-molecule fluorescence microscopy to visualize how Bacillus subtilis SMC (BsSMC) interacts with flow-stretched DNAs. We report that BsSMC can slide on DNA, switching between static binding and diffusion. At higher concentrations, BsSMCs form clusters that condense DNA in a weakly ATP-dependent manner. ATP increases the apparent cooperativity of DNA condensation, demonstrating that BsSMC can interact cooperatively through their ATPase head domains. Consistent with these results, ATPase mutants compact DNA more slowly than wild-type BsSMC in the presence of ATP. Our results suggest that transiently static BsSMC molecules can nucleate the formation of clusters that act to locally condense the chromosome while forming long-range DNA bridges. PMID:26725510

  2. Pool boiling and condensation analysis for a vertical tube bundle condenser

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, W.; Wolf, B., E-mail: zhouw@purdue.edu [Purdue Univ., West Lafayette, Indiana (United States); Revankar, S.T., E-mail: shripad@ecn.purdue.edu [Purdue Univ., West Lafayette, Indiana (United States); POSTECH, Pohang (Korea, Republic of)

    2011-07-01

    An experimental and theoretical study is performed for the steam condensation in a vertical tube bundle passive condenser simulating PCCS condenser in the ESBWR. Four condenser tubes are submerged in a water pool where the heat from the condenser tube is removed through boiling heat transfer. Condenser tubes with a full length/diameter scale are used to obtain the condensation data with various process parameters. The comparison of tube bundle experimental data with the single tube data by both the experiments and models shows that the single tube secondary heat transfer coefficient (HTC) is between 25% - 35% less than what was recorded for the tube bundle, and the tube bundle condensation rates are slightly higher than the data from the single tube test sections due to turbulent mixing effect which increases the condensation heat removal. The turbulent mixing on the secondary side decreases the DT between pool water and condenser tube outer wall, causing an increase in secondary HTC. This increase in secondary HTC thus results in higher condensate mass flow rates. Tube bundle boundary layer model and heat and mass analogy model were then developed for the prediction of the filmwise steam condensation with noncondensable (NC) gas in a vertical tube bundle. The predictions from the models are compared with the experimental data for various complete condensation and through flow conditions and the agreement is satisfactory. The local parameters predicted by the boundary layer model and heat and mass analogy model with tube bundle pool boiling can also be predicted with the axial distance from entrance for different NC gas fractions and system pressures. (author)

  3. Pool boiling and condensation analysis for a vertical tube bundle condenser

    International Nuclear Information System (INIS)

    An experimental and theoretical study is performed for the steam condensation in a vertical tube bundle passive condenser simulating PCCS condenser in the ESBWR. Four condenser tubes are submerged in a water pool where the heat from the condenser tube is removed through boiling heat transfer. Condenser tubes with a full length/diameter scale are used to obtain the condensation data with various process parameters. The comparison of tube bundle experimental data with the single tube data by both the experiments and models shows that the single tube secondary heat transfer coefficient (HTC) is between 25% - 35% less than what was recorded for the tube bundle, and the tube bundle condensation rates are slightly higher than the data from the single tube test sections due to turbulent mixing effect which increases the condensation heat removal. The turbulent mixing on the secondary side decreases the DT between pool water and condenser tube outer wall, causing an increase in secondary HTC. This increase in secondary HTC thus results in higher condensate mass flow rates. Tube bundle boundary layer model and heat and mass analogy model were then developed for the prediction of the filmwise steam condensation with noncondensable (NC) gas in a vertical tube bundle. The predictions from the models are compared with the experimental data for various complete condensation and through flow conditions and the agreement is satisfactory. The local parameters predicted by the boundary layer model and heat and mass analogy model with tube bundle pool boiling can also be predicted with the axial distance from entrance for different NC gas fractions and system pressures. (author)

  4. Undetected sex chromosome aneuploidy by chromosomal microarray.

    Science.gov (United States)

    Markus-Bustani, Keren; Yaron, Yuval; Goldstein, Myriam; Orr-Urtreger, Avi; Ben-Shachar, Shay

    2012-11-01

    We report on a case of a female fetus found to be mosaic for Turner syndrome (45,X) and trisomy X (47,XXX). Chromosomal microarray analysis (CMA) failed to detect the aneuploidy because of a normal average dosage of the X chromosome. This case represents an unusual instance in which CMA may not detect chromosomal aberrations. Such a possibility should be taken into consideration in similar cases where CMA is used in a clinical setting.

  5. ASAR15, A cis-acting locus that controls chromosome-wide replication timing and stability of human chromosome 15.

    Directory of Open Access Journals (Sweden)

    Nathan Donley

    2015-01-01

    Full Text Available DNA replication initiates at multiple sites along each mammalian chromosome at different times during each S phase, following a temporal replication program. We have used a Cre/loxP-based strategy to identify cis-acting elements that control this replication-timing program on individual human chromosomes. In this report, we show that rearrangements at a complex locus at chromosome 15q24.3 result in delayed replication and structural instability of human chromosome 15. Characterization of this locus identified long, RNA transcripts that are retained in the nucleus and form a "cloud" on one homolog of chromosome 15. We also found that this locus displays asynchronous replication that is coordinated with other random monoallelic genes on chromosome 15. We have named this locus ASynchronous replication and Autosomal RNA on chromosome 15, or ASAR15. Previously, we found that disruption of the ASAR6 lincRNA gene results in delayed replication, delayed mitotic condensation and structural instability of human chromosome 6. Previous studies in the mouse found that deletion of the Xist gene, from the X chromosome in adult somatic cells, results in a delayed replication and instability phenotype that is indistinguishable from the phenotype caused by disruption of either ASAR6 or ASAR15. In addition, delayed replication and chromosome instability were detected following structural rearrangement of many different human or mouse chromosomes. These observations suggest that all mammalian chromosomes contain similar cis-acting loci. Thus, under this scenario, all mammalian chromosomes contain four distinct types of essential cis-acting elements: origins, telomeres, centromeres and "inactivation/stability centers", all functioning to promote proper replication, segregation and structural stability of each chromosome.

  6. Non-SMC condensin I complex proteins control chromosome segregation and survival of proliferating cells in the zebrafish neural retina

    Directory of Open Access Journals (Sweden)

    Harris William A

    2009-07-01

    Full Text Available Abstract Background The condensation of chromosomes and correct sister chromatid segregation during cell division is an essential feature of all proliferative cells. Structural maintenance of chromosomes (SMC and non-SMC proteins form the condensin I complex and regulate chromosome condensation and segregation during mitosis. However, due to the lack of appropriate mutants, the function of the condensin I complex during vertebrate development has not been described. Results Here, we report the positional cloning and detailed characterization of retinal phenotypes of a zebrafish mutation at the cap-g locus. High resolution live imaging reveals that the progression of mitosis between prometa- to telophase is delayed and that sister chromatid segregation is impaired upon loss of CAP-G. CAP-G associates with chromosomes between prometa- and telophase of the cell cycle. Loss of the interaction partners CAP-H and CAP-D2 causes cytoplasmic mislocalization of CAP-G throughout mitosis. DNA content analysis reveals increased genomic imbalances upon loss of non-SMC condensin I subunits. Within the retina, loss of condensin I function causes increased rates of apoptosis among cells within the proliferative ciliary marginal zone (CMZ whereas postmitotic retinal cells are viable. Inhibition of p53-mediated apoptosis partially rescues cell numbers in cap-g mutant retinae and allows normal layering of retinal cell types without alleviating their aberrant nuclear sizes. Conclusion Our findings indicate that the condensin I complex is particularly important within rapidly amplifying progenitor cell populations to ensure faithful chromosome segregation. In contrast, differentiation of postmitotic retinal cells is not impaired upon polyploidization.

  7. Heat Transfer in Flue Gas with Vapor Condensation

    Institute of Scientific and Technical Information of China (English)

    贾力; 彭晓峰

    2002-01-01

    This paper combines the film model with Nusselt's condensation theory to analyze the effects of water vapor condensation on the heat transfer performance of flue gas flowing through a vertical tube. The analysis compares the condensation and convective heat transfer rates. For the concentration range investigated, the water vapor condensation transfers more energy than the flue gas convection, but the convective heat transfer can not be neglected. The heat transfer intensification due to the condensation increased as the water vapor fraction increased. The theoretical results compared well with experimental data.

  8. Exceptional Complex Chromosomal Rearrangements in Three Generations

    Directory of Open Access Journals (Sweden)

    Hannie Kartapradja

    2015-01-01

    Full Text Available We report an exceptional complex chromosomal rearrangement (CCR found in three individuals in a family that involves 4 chromosomes with 5 breakpoints. The CCR was ascertained in a phenotypically abnormal newborn with additional chromosomal material on the short arm of chromosome 4. Maternal karyotyping indicated that the mother carried an apparently balanced CCR involving chromosomes 4, 6, 11, and 18. Maternal transmission of the derivative chromosome 4 resulted in partial trisomy for chromosomes 6q and 18q and a partial monosomy of chromosome 4p in the proband. Further family studies found that the maternal grandmother carried the same apparently balanced CCR as the proband’s mother, which was confirmed using the whole chromosome painting (WCP FISH. High resolution whole genome microarray analysis of DNA from the proband’s mother found no evidence for copy number imbalance in the vicinity of the CCR translocation breakpoints, or elsewhere in the genome, providing evidence that the mother’s and grandmother’s CCRs were balanced at a molecular level. This structural rearrangement can be categorized as an exceptional CCR due to its complexity and is a rare example of an exceptional CCR being transmitted in balanced and/or unbalanced form across three generations.

  9. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J;

    1983-01-01

    The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...... A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were compared...... to women having amniocentesis, although considered not to have any increased risk of fetal chromosome abnormality (1390 pregnancies, group B). They were also compared with 750 consecutive pregnancies in women 25-34 years of age, in whom all heritable diseases were excluded (group C). The risk of unbalanced...

  10. Chromosome Disorder Outreach

    Science.gov (United States)

    ... BLOG Join Us Donate You are not alone. Chromosome Disorder Outreach, Inc. is a non-profit organization, ... Support For all those diagnosed with any rare chromosome disorder. Since 1992, CDO has supported the parents ...

  11. A multi-field approach to DNA condensation

    Science.gov (United States)

    Ran, Shi-Yong; Jia, Jun-Li

    2015-12-01

    DNA condensation is an important process in many fields including life sciences, polymer physics, and applied technology. In the nucleus, DNA is condensed into chromosomes. In polymer physics, DNA is treated as a semi-flexible molecule and a polyelectrolyte. Many agents, including multi-valent cations, surfactants, and neutral poor solvents, can cause DNA condensation, also referred to as coil-globule transition. Moreover, DNA condensation has been used for extraction and gene delivery in applied technology. Many physical theories have been presented to elucidate the mechanism underlying DNA condensation, including the counterion correlation theory, the electrostatic zipper theory, and the hydration force theory. Recently several single-molecule studies have focused on DNA condensation, shedding new light on old concepts. In this document, the multi-field concepts and theories related to DNA condensation are introduced and clarified as well as the advances and considerations of single-molecule DNA condensation experiments are introduced. Project supported by the National Natural Science Foundation of China (Grant Nos. 21204065 and 20934004) and the Natural Science Foundation of Zhejiang Province, China (Grant No. Y4110357).

  12. Guarding chromosomes from oxidative DNA damage to the very end

    Institute of Scientific and Technical Information of China (English)

    Rong Tan; Li Lan

    2016-01-01

    The ends of each chromosome are capped by the telomere assembly to protect chromosomal integrity from telomere attrition and DNA damage.In response to DNA damage,DNA repair factors are enriched at damage sites by a sophisticated signaling and recruitment cascade.However,DNA damage response at telomeres is different from non-telomeric region of genomic DNA due to specialized sequences and structures of the telomeres.In the course of normal DNA replication or DNA damage repair,both the telomere shelterin protein complex and the condensed telomeric chromatin structure in mammalian cells are modified to protect telomeres from exposing free DNA ends which are subject to both telemere shortening and chromosome end fusion.Initiation of either homologous recombination or non-homologous end joint repair at telomeres requires disassembling andaor post-translational modifications of the shelterin complex and telomeric chromatin.In addition,cancer cells utilize distinct mechanisms to maintain telomere length and cell survival upon damage.In this review,we summarize current studies that focus on telomere end protection and telomere DNA repair using different methodologies to model telomere DNA damage and disruption.These include genetic ablation of sheltering proteins,targeting endonuclease to telomeres,and delivering oxidative damage directly.These different approaches,when combined,offer better understanding of the mechanistic differences in DNA damage response between telomeric and genomic DNA,which will provide new hope to identify potential cancer therapeutic targets to curtail cancer cell proliferation via induction of telomere dysfunctions.

  13. Measure Guideline: Evaporative Condensers

    Energy Technology Data Exchange (ETDEWEB)

    German, A [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Dakin, B. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Hoeschele, M. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2012-03-01

    This measure guideline on evaporative condensers provides information on properly designing, installing, and maintaining evaporative condenser systems as well as understanding the benefits, costs, and tradeoffs. This is a prescriptive approach that outlines selection criteria, design and installation procedures, and operation and maintenance best practices.

  14. Systematic text condensation

    DEFF Research Database (Denmark)

    Malterud, Kirsti

    2012-01-01

    To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies.......To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies....

  15. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric C-b

  16. Chromosome painting in plants.

    NARCIS (Netherlands)

    Schubert, I.; Fransz, P.F.; Fuchs, J.; Jong, de J.H.

    2001-01-01

    The current 'state-of-art' as to chromosome painting in plants is reviewed. We define different situations described as painting so far: i) Genomic in situ hybridisation (GISH) with total genomic DNA to distinguish alien chromosomes on the basis of divergent dispersed repeats, ii) 'Chromosomal in si

  17. Freeze-Tolerant Condensers

    Science.gov (United States)

    Crowley, Christopher J.; Elkouhk, Nabil

    2004-01-01

    Two condensers designed for use in dissipating heat carried by working fluids feature two-phase, self-adjusting configurations such that their working lengths automatically vary to suit their input power levels and/or heat-sink temperatures. A key advantage of these condensers is that they can function even if the temperatures of their heat sinks fall below the freezing temperatures of their working fluids and the fluids freeze. The condensers can even be restarted from the frozen condition. The top part of the figure depicts the layout of the first condenser. A two-phase (liquid and vapor) condenser/vapor tube is thermally connected to a heat sink typically, a radiatively or convectively cooled metal panel. A single-phase (liquid) condensate-return tube (return artery) is also thermally connected to the heat sink. At intervals along their lengths, the condenser/vapor tube and the return artery are interconnected through porous plugs. This condenser configuration affords tolerance of freezing, variable effective thermal conductance (such that the return temperature remains nearly constant, independently of the ultimate sink temperature), and overall pressure drop smaller than it would be without the porous interconnections. An additional benefit of this configuration is that the condenser can be made to recover from the completely frozen condition either without using heaters, or else with the help of heaters much smaller than would otherwise be needed. The second condenser affords the same advantages and is based on a similar principle, but it has a different configuration that affords improved flow of working fluid, simplified construction, reduced weight, and faster recovery from a frozen condition.

  18. Assembly and disassembly of mammalian chromosome pellicle

    Institute of Scientific and Technical Information of China (English)

    NIZUMEI; JELITTLE; 等

    1992-01-01

    By means of indirect double immunofluorescent staining,the coordination of PI antigen and perichromonucleolin(PCN),the constituent of nuclear periphery and nucleolus respectively,in the assembly and disassembly of chromosome pellicle during mitosis was studied.It was found that in 3T3 cells,during mitosis PI antigen began to coat the condensing chromosome surface earlier than PCN did.However,both of them completed their coating on chromosome at approximately the same stage of mitosis,prometaphase metaphase,The dissociation of mitosis,Prometaphase metaphase.The dissociation of PI antigen from chromosome pellicle to participate the formation of nuclear periphery took place also ahead of that of PCN,At early telophase PI antigen had been extensively involved in the formation of nuclear periphery,while PCN remained in association with the surface of decondensing chromosomes.At late telophase,when PI antigen was localized in an fairly well formed nuclear periphery,PCN was in a stage of forming prenucleolar bodies.

  19. Scalable graphene coatings for enhanced condensation heat transfer.

    Science.gov (United States)

    Preston, Daniel J; Mafra, Daniela L; Miljkovic, Nenad; Kong, Jing; Wang, Evelyn N

    2015-05-13

    Water vapor condensation is commonly observed in nature and routinely used as an effective means of transferring heat with dropwise condensation on nonwetting surfaces exhibiting heat transfer improvement compared to filmwise condensation on wetting surfaces. However, state-of-the-art techniques to promote dropwise condensation rely on functional hydrophobic coatings that either have challenges with chemical stability or are so thick that any potential heat transfer improvement is negated due to the added thermal resistance of the coating. In this work, we show the effectiveness of ultrathin scalable chemical vapor deposited (CVD) graphene coatings to promote dropwise condensation while offering robust chemical stability and maintaining low thermal resistance. Heat transfer enhancements of 4× were demonstrated compared to filmwise condensation, and the robustness of these CVD coatings was superior to typical hydrophobic monolayer coatings. Our results indicate that graphene is a promising surface coating to promote dropwise condensation of water in industrial conditions with the potential for scalable application via CVD.

  20. Schizophrenia and chromosomal deletions

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, E.A.; Baldini, A. [Baylor College of Medicine, Houston, TX (United States); Morris, M. A. [Univ. of Geneva School of Medicine, NY (United States)] [and others

    1995-06-01

    Recent genetic linkage analysis studies have suggested the presence of a schizophrenia locus on the chromosomal region 22q11-q13. Schizophrenia has also been frequently observed in patients affected with velo-cardio-facial syndrome (VCFS), a disorder frequently associated with deletions within 22q11.1. It has been hypothesized that psychosis in VCFS may be due to deletion of the catechol-o-methyl transferase gene. Prompted by these observations, we screened for 22q11 deletions in a population of 100 schizophrenics selected from the Maryland Epidemiological Sample. Our results show that there are schizophrenic patients carrying a deletion of 22q11.1 and a mild VCFS phenotype that might remain unrecognized. These findings should encourage a search for a schizophrenia-susceptibility gene within the deleted region and alert those in clinical practice to the possible presence of a mild VCFS phenotype associated with schizophrenia. 9 refs.

  1. Dual condensates at finite isospin chemical potential

    CERN Document Server

    Zhang, Zhao

    2015-01-01

    The dual observables as order parameters for center symmetry are tested at finite isospin chemical potential $\\mu_I$ in a Polyakov-loop enhanced chiral model of QCD with physical quark masses. As a counterpart of the dressed Polyakov-loop, the first Fourier moment of pion condensate is introduced for $\\mu_I>{m_\\pi}/{2}$ under the temporal twisted boundary conditions for quarks. We demonstrate that this dual condensate exhibits the similar temperature dependence as the conventional Polyakov-loop. We confirm that its rapid increase with $T$ is driven by the evaporating of pion condensation. On the other hand, the dressed Polyakov-loop shows abnormal thermal behavior, which even decreases with $T$ at low temperatures due to the influence of pion condensate. We thus argue that in QCD the critical temperature extracting from a dual observable may have nothing to do with the quark confinement-deconfinement transition if the quark mass is very small.

  2. Sedimentary condensation and authigenesis

    Science.gov (United States)

    Föllmi, Karl

    2016-04-01

    Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

  3. Physics of condensed matter

    CERN Document Server

    Misra, Prasanta K

    2012-01-01

    Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be

  4. Chimpanzee chromosome 12 is homologous to human chromosome 2q

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Most of the 46 human chromosomes find their counterparts in the 48 chimpanzee chromosomes except for chromosome 2 which has been hypothesized to have been derived from a centric fusion of two chimpanzee acrocentric chromosomes. These two chromosomes correspond to the human chromosomes 2p and 2g. This conclusion is based primarily on chromosome banding techniques, and the somatic cell hybridization technique has also been used. (HLW)

  5. Dropwise condensation dynamics in humid air

    Science.gov (United States)

    Castillo Chacon, Julian Eduardo

    Dropwise condensation of atmospheric water vapor is important in multiple practical engineering applications. The roles of environmental factors and surface morphology/chemistry on the condensation dynamics need to be better understood to enable efficient water-harvesting, dehumidication, and other psychrometric processes. Systems and surfaces that promote faster condensation rates and self-shedding of condensate droplets could lead to improved mass transfer rates and higher water yields in harvesting applications. The thesis presents the design and construction of an experimental facility that allows visualization of the condensation process as a function of relative humidity. Dropwise condensation experiments are performed on a vertically oriented, hydrophobic surface at a controlled relative humidity and surface subcooling temperature. The distribution and growth of water droplets are monitored across the surface at different relative humidities (45%, 50%, 55%, and 70%) at a constant surface subcooling temperature of 15 °C below the ambient temperature. The droplet growth dynamics exhibits a strong dependency on relative humidity in the early stages during which there is a large population of small droplets on the surface and single droplet growth dominates over coalescence effects. At later stages, the dynamics of droplet growth is insensitive to relative humidity due to the dominance of coalescence effects. The overall volumetric rate of condensation on the surface is also assessed as a function of time and ambient relative humidity. Low relative humidity conditions not only slow the absolute rate of condensation, but also prolong an initial transient regime over which the condensation rate remains significantly below the steady-state value. The current state-of-the-art in dropwise condensation research indicates the need for systematic experimental investigations as a function of relative humidity. The improved understanding of the relative humidity

  6. THE COLOR GLASS CONDENSATE.

    Energy Technology Data Exchange (ETDEWEB)

    MCLERRAN,L.

    2001-08-26

    The Color Glass Condensate is a state of high density gluonic matter which controls the high energy limit of hadronic interactions. Its properties are important for the initial conditions for matter produced at RHIC.

  7. Chromosome Territory Modeller and Viewer

    Science.gov (United States)

    Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi–a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license. PMID:27505434

  8. Chromosome Territory Modeller and Viewer.

    Science.gov (United States)

    Tkacz, Magdalena A; Chromiński, Kornel; Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi-a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license. PMID:27505434

  9. Thin accretion disks around cold Bose–Einstein condensate stars

    OpenAIRE

    Dănilă, Bogdan; Harko, Tiberiu; Kovács, Zoltán

    2015-01-01

    Due to their superfluid properties some compact astrophysical objects, like neutron or quark stars, may contain a significant part of their matter in the form of a Bose-Einstein Condensate. Observationally distinguishing between neutron/quark stars and Bose-Einstein Condensate stars is a major challenge for this latter theoretical model. An observational possibility of indirectly distinguishing Bose-Einstein Condensate stars from neutron/quark stars is through the study of the thin accretion ...

  10. Phase diffusion in a Bose-Einstein condensate of light

    OpenAIRE

    de Leeuw, A.W.; van der Wurff, E. C. I.; Duine, R. A.; Stoof, H.T.C.

    2014-01-01

    We study phase diffusion in a Bose-Einstein condensate of light in a dye-filled optical microcavity, i.e., the spreading of the probability distribution for the condensate phase. To observe this phenomenon, we propose an interference experiment between the condensed photons and an external laser. We determine the average interference patterns, considering quantum and thermal fluctuations as well as dissipative effects due to the dye. Moreover, we show that a representative outcome of individu...

  11. Measure Guideline: Evaporative Condensers

    Energy Technology Data Exchange (ETDEWEB)

    German, A.; Dakin, B.; Hoeschele, M.

    2012-03-01

    The purpose of this measure guideline on evaporative condensers is to provide information on a cost-effective solution for energy and demand savings in homes with cooling loads. This is a prescriptive approach that outlines selection criteria, design and installation procedures, and operation and maintenance best practices. This document has been prepared to provide a process for properly designing, installing, and maintaining evaporative condenser systems as well as understanding the benefits, costs, and tradeoffs.

  12. Boilers, evaporators, and condensers

    International Nuclear Information System (INIS)

    This book reports on the boilers, evaporators and condensers that are used in power plants including nuclear power plants. Topics included are forced convection for single-phase side heat exchangers, heat exchanger fouling, industrial heat exchanger design, fossil-fuel-fired boilers, once through boilers, thermodynamic designs of fossil fuel-first boilers, evaporators and condensers in refrigeration and air conditioning systems (with respect to reducing CFC's) and nuclear steam generators

  13. Novel gene acquisition on carnivore Y chromosomes.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we used direct cDNA selection to isolate and evaluate the extent of novel Y chromosome gene acquisition in the genome of the domestic cat, a species from a different mammalian superorder than human, chimpanzee, and mouse (currently being sequenced. We discovered four novel Y chromosome genes that do not have functional copies in the finished human male-specific region of the Y or on other mammalian Y chromosomes explored thus far. Two genes are derived from putative autosomal progenitors, and the other two have X chromosome homologs from different evolutionary strata. All four genes were shown to be multicopy and expressed predominantly or exclusively in testes, suggesting that their duplication and specialization for testis function were selected for because they enhance spermatogenesis. Two of these genes have testis-expressed, Y-borne copies in the dog genome as well. The absence of the four newly described genes on other characterized mammalian Y chromosomes demonstrates the gene novelty on this chromosome between mammalian orders, suggesting it harbors many lineage-specific genes that may go undetected by traditional comparative genomic approaches. Specific plans to identify the male-specific genes encoded in the Y chromosome of mammals should be a priority.

  14. Dual condensates at finite isospin chemical potential

    Directory of Open Access Journals (Sweden)

    Zhao Zhang

    2016-02-01

    Full Text Available The dual observables as order parameters for center symmetry are tested at finite isospin chemical potential μI in a Polyakov-loop enhanced chiral model of QCD with physical quark masses. As a counterpart of the dressed Polyakov-loop, the first Fourier moment of pion condensate is introduced for μI>mπ/2 under the temporal twisted boundary conditions for quarks. We demonstrate that this dual condensate exhibits the similar temperature dependence as the conventional Polyakov-loop. We confirm that its rapid increase with T is driven by the evaporating of pion condensation. On the other hand, the dressed Polyakov-loop shows abnormal thermal behavior, which even decreases with T at low temperatures due to the influence of pion condensate. We also find that the dressed Polyakov-loop always rises most steeply at the chiral transition temperature, which is consistent with the previous results in Nambu–Jona-Lasinio (NJL model and its variants without considering the center symmetry. Since both quantities are strongly affected by the chiral symmetry and pion condensation, we conclude that it is difficult to clarify the deconfinement transition from the dual condensates in this situation within this model.

  15. Dual condensates at finite isospin chemical potential

    Science.gov (United States)

    Zhang, Zhao; Miao, Qing

    2016-02-01

    The dual observables as order parameters for center symmetry are tested at finite isospin chemical potential μI in a Polyakov-loop enhanced chiral model of QCD with physical quark masses. As a counterpart of the dressed Polyakov-loop, the first Fourier moment of pion condensate is introduced for μI >mπ / 2 under the temporal twisted boundary conditions for quarks. We demonstrate that this dual condensate exhibits the similar temperature dependence as the conventional Polyakov-loop. We confirm that its rapid increase with T is driven by the evaporating of pion condensation. On the other hand, the dressed Polyakov-loop shows abnormal thermal behavior, which even decreases with T at low temperatures due to the influence of pion condensate. We also find that the dressed Polyakov-loop always rises most steeply at the chiral transition temperature, which is consistent with the previous results in Nambu-Jona-Lasinio (NJL) model and its variants without considering the center symmetry. Since both quantities are strongly affected by the chiral symmetry and pion condensation, we conclude that it is difficult to clarify the deconfinement transition from the dual condensates in this situation within this model.

  16. Localization of latency-associated nuclear antigen (LANA) on mitotic chromosomes.

    Science.gov (United States)

    Rahayu, Retno; Ohsaki, Eriko; Omori, Hiroko; Ueda, Keiji

    2016-09-01

    In latent infection of Kaposi's sarcoma-associated herpesvirus (KSHV), viral gene expression is extremely limited and copy numbers of viral genomes remain constant. Latency-associated nuclear antigen (LANA) is known to have a role in maintaining viral genome copy numbers in growing cells. Several studies have shown that LANA is localized in particular regions on mitotic chromosomes, such as centromeres/pericentromeres. We independently examined the distinct localization of LANA on mitotic chromosomes during mitosis, using super-resolution laser confocal microscopy and correlative fluorescence microscopy-electron microscopy (FM-EM) analyses. We found that the majority of LANA were not localized at particular regions such as telomeres/peritelomeres, centromeres/pericentromeres, and cohesion sites, but at the bodies of condensed chromosomes. Thus, LANA may undergo various interactions with the host factors on the condensed chromosomes in order to tether the viral genome to mitotic chromosomes and realize faithful viral genome segregation during cell division. PMID:27254595

  17. The Effect of Capillary Number on a Condensate Blockage in Gas Condensate Reservoirs

    Directory of Open Access Journals (Sweden)

    Saifon DAUNGKAEW

    2004-01-01

    Full Text Available In the petroleum industry, gas condensate reservoirs are becoming more common as exploration targets. However, there is a lack of knowledge of the reservoir behaviour mainly due to its complexity in the near wellbore region, where two phases, i.e. reservoir gas and condensate coexist when the wellbore pressure drops below the dew point pressure. The condensation process causes a reduction of the gas productivity (1. It has been reported in the literature that there is an increasing gas mobility zone due to a capillary number effect in the immediate vicinity of the wellbore in gas condensate reservoirs (2. This zone, called “velocitystripping zone”, compensates the well productivity loss due to the condensate drop-out. However, existence of this zone has just been recently found in an actual well test data (3,4. There is no conclusive study of this velocity-stripping zone in this type of reservoir. The objective of this study was to gain a better understanding of near wellbore effects in gas condensate reservoirs under production and well testing.

  18. The Precarious Prokaryotic Chromosome

    OpenAIRE

    Kuzminov, Andrei

    2014-01-01

    Evolutionary selection for optimal genome preservation, replication, and expression should yield similar chromosome organizations in any type of cells. And yet, the chromosome organization is surprisingly different between eukaryotes and prokaryotes. The nuclear versus cytoplasmic accommodation of genetic material accounts for the distinct eukaryotic and prokaryotic modes of genome evolution, but it falls short of explaining the differences in the chromosome organization. I propose that the t...

  19. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B;

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation...... with the probe L1.26 confirmed the derivation from chromosome 13 and DNA polymorphism analysis showed maternal origin of the ring chromosome. Our results, together with a review of previous reports of cases with ring chromosome 13 with identified breakpoints, could neither support the theory of distinct clinical...

  20. Mitotic chromosome compaction via active loop extrusion

    Science.gov (United States)

    Goloborodko, Anton; Imakaev, Maxim; Marko, John; Mirny, Leonid; MIT-Northwestern Team

    During cell division, two copies of each chromosome are segregated from each other and compacted more than hundred-fold into the canonical X-shaped structures. According to earlier microscopic observations and the recent Hi-C study, chromosomes are compacted into arrays of consecutive loops of ~100 kilobases. Mechanisms that lead to formation of such loop arrays are largely unknown. Here we propose that, during cell division, chromosomes can be compacted by enzymes that extrude loops on chromatin fibers. First, we use computer simulations and analytical modeling to show that a system of loop-extruding enzymes on a chromatin fiber self-organizes into an array of consecutive dynamic loops. Second, we model the process of loop extrusion in 3D and show that, coupled with the topo II strand-passing activity, it leads to robust compaction and segregation of sister chromatids. This mechanism of chromosomal condensation and segregation does not require additional proteins or specific DNA markup and is robust against variations in the number and properties of such loop extruding enzymes. Work at NU was supported by the NSF through Grants DMR-1206868 and MCB-1022117, and by the NIH through Grants GM105847 and CA193419. Work at MIT was supported by the NIH through Grants GM114190 R01HG003143.

  1. Down-Turner Syndrome: A Case with Double Monoclonal Chromosomal Abnormality

    OpenAIRE

    Manassero-Morales, Gioconda; Alvarez-Manassero, Denisse; Merino-Luna, Alfredo

    2016-01-01

    Introduction. The coexistence of Down and Turner syndromes due to double chromosome aneuploidy is very rare; it is even more rare to find the presence of a double monoclonal chromosomal abnormality. Objective. To report a unique case of double monoclonal chromosomal abnormality with trisomy of chromosome 21 and an X ring chromosome in all cells studied; no previous report has been found. Case Report. Female, 28 months old, with pathological short stature from birth, with the following dysmorp...

  2. Titanium condenser tubes

    International Nuclear Information System (INIS)

    The corrosion resistance of titanium in sea water is extremely excellent, but titanium tubes are expensive, and the copper alloy tubes resistant in polluted sea water were developed, therefore they were not used practically. In 1970, ammonia attack was found on the copper alloy tubes in the air-cooled portion of condensers, and titanium tubes have been used as the countermeasure. As the result of the use, the galvanic attack an copper alloy tube plates with titanium tubes as cathode and the hydrogen absorption at titanium tube ends owing to excess electrolytic protection were observed, but the corrosion resistance of titanium tubes was perfect. These problems can be controlled by the application of proper electrolytic protection. The condensers with all titanium tubes adopted recently in USA are intended to realize perfectly no-leak condensers as the countermeasure to the corrosion in steam generators of PWR plants. Regarding large condensers of nowadays, three problems are pointed out, namely the vibration of condenser tubes, the method of joining tubes and tube plates, and the tubes of no coolant leak. These three problems in case of titanium tubes were studied, and the problem of the fouling of tubes was also examined. The intervals of supporting plates for titanium tubes should be narrowed. The joining of titanium tubes and titanium tube plates by welding is feasible and promising. The cleaning with sponge balls is effective to control fouling. (Kako, I.)

  3. Nuclear assembly of purified Crythecodinium cohnii chromosomes in cell—free extracts of Xenopus laevis eggs

    Institute of Scientific and Technical Information of China (English)

    LIUXIAOLING; YANSHEN

    2000-01-01

    Incubation of dinoflagellate Crythecodinium cohnii chromosomes in cytoplasmic extracts of unfertilized Xenopus laevis eggs resulted in chromosomes decondensation and recondensation,nuclear envelope assembly,and nuclear reconstitution.Dinoflagellate Crythecodinium cohnii is a kind of primitive eukaryote which possesses numerous permanently condensed chromosomes and discontinuous double-layered nuclear membrane throughout the cell cycle.The assembled nuclei,being surrounded by a continuous double membrane containing nuclear pores and the uniformly dispersed chromatin fibers are morphologically distinguishable from that of Dinoflagellate Crythecodinium cohnii.However,incubation of dinoflagellate Cyrthecodinium cohnii chromosomes in the extracts from dinoflagellate Crythecodinium cohnii cells does not induce nuclear reconstitution.

  4. Nuclear assembly of purified Crythecodinium cohnii chromosomes in cell-free extracts of Xenopus laevis eggs

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Incubation of dinoflagellate Crythecodinium cohnii chromosomes in cytoplasmic extracts of unfertilized Xenopus laevis eggs resulted in chromosomes decondensation and recondensation, nuclear envelope assembly, and nuclear reconstitution.Dinoflagellate Crythecodinium cohnii is a kind of primitive eukaryote which possesses numerous permanently condensed chromosomes and discontinuous double-layered nuclear membrane throughout the cell cycle. The assembled nuclei, being surrounded by a continuous double membrane containing nuclear pores and the uniformly dispersed chromatin fibers are morphologically distinguishable from that of Dinoflagellate Crythecodinium cohnii. However, incubation of dinoflagellate Crythecodinium cohnii chromosomes in the extracts from dinoflagellate Crythecodinium cohnii cells does not induce nuclear reconstitution.

  5. Nonresonant optical control of a spinor polariton condensate

    Science.gov (United States)

    Askitopoulos, A.; Kalinin, K.; Liew, T. C. H.; Cilibrizzi, P.; Hatzopoulos, Z.; Savvidis, P. G.; Berloff, N. G.; Lagoudakis, P. G.

    2016-05-01

    We investigate the spin dynamics of polariton condensates spatially separated from and effectively confined by the pumping exciton reservoir. We obtain a strong correlation between the ellipticity of the nonresonant optical pump and the degree of circular polarization (DCP) of the condensate at the onset of condensation. With increasing excitation density we observe a reversal of the DCP. The spin dynamics of the trapped condensate are described within the framework of the spinor complex Ginzburg-Landau equations in the Josephson regime, where the dynamics of the system are reduced to a current-driven Josephson junction. We show that the observed spin reversal is due to the interplay between an internal Josephson coupling effect and the detuning of the two projections of the spinor condensate via transition from a synchronized to a desynchronized regime. These results suggest that spinor polariton condensates can be controlled by tuning the nonresonant excitation density offering applications in electrically pumped polariton spin switches.

  6. Avalanches in a Bose-Einstein condensate

    OpenAIRE

    Schuster, J; A. Marte; Amtage, S; Sang, B.; Rempe, G.; Beijerinck, HCW Herman

    2001-01-01

    Collisional avalanches are identified to be responsible for an 8-fold increase of the initial loss rate of a large 87-Rb condensate. We show that the collisional opacity of an ultra-cold gas exhibits a critical value. When exceeded, losses due to inelastic collisions are substantially enhanced. Under these circumstances, reaching the hydrodynamic regime in conventional BEC experiments is highly questionable.

  7. Electric-Field-Enhanced Jumping-Droplet Condensation

    Science.gov (United States)

    Miljkovic, Nenad; Preston, Daniel; Enright, Ryan; Limia, Alexander; Wang, Evelyn

    2013-11-01

    When condensed droplets coalesce on a superhydrophobic surface, the resulting droplet can jump due to the conversion of surface energy into kinetic energy. This frequent out-of-plane droplet jumping has the potential to enhance condensation heat and mass transfer. In this work, we demonstrated that these jumping droplets accumulate positive charge that can be used to further increase condensation heat transfer via electric fields. We studied droplet jumping dynamics on silanized nanostructured copper oxide surfaces. By characterizing the droplet trajectories under various applied external electric fields (0 - 50 V/cm), we show that condensation on superhydrophobic surfaces results in a buildup of negative surface charge (OH-) due to dissociated water ion adsorption on the superhydrophobic coating. Consequently, the opposite charge (H3O +) accumulates on the coalesced jumping droplet. Using this knowledge, we demonstrate electric-field-enhanced jumping droplet condensation whereby an external electric field opposes the droplet vapor flow entrainment towards the condensing surface to increase the droplet removal rate and overall surface heat transfer by 100% when compared to state-of-the-art dropwise condensing surfaces. This work not only shows significant condensation heat transfer enhancement through the passive charging of condensed droplets, but promises a low cost approach to increase efficiency for applications such as atmospheric water harvesting and dehumidification.

  8. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli;

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two chromoso...

  9. Condensed matter physics

    CERN Document Server

    Isihara, A

    2007-01-01

    More than a graduate text and advanced research guide on condensed matter physics, this volume is useful to plasma physicists and polymer chemists, and their students. It emphasizes applications of statistical mechanics to a variety of systems in condensed matter physics rather than theoretical derivations of the principles of statistical mechanics and techniques. Isihara addresses a dozen different subjects in separate chapters, each designed to be directly accessible and used independently of previous chapters. Topics include simple liquids, electron systems and correlations, two-dimensional

  10. Effects of oxaliplatin on DNA condensation

    Institute of Scientific and Technical Information of China (English)

    JU HaiPeng; ZHANG HongYan; LI Wei; WANG PengYe

    2014-01-01

    In this paper the interactions between DNA and anti-cancer drug oxaliplatin were investigated by using magnetic tweezers.The dynamics of DNA condensation due to oxaliplatin was traced under various forces.It is found that torsion constraint in DNA enhances the ability of oxaliplatin for shortening DNA.The transplatin helps oxaliplatin combine to DNA and increase the rate of DNA condensation.All these results are consistent to the previously proposed model and are helpful for further investigation of interaction between DNA and oxaliplatin.

  11. Y-chromosome polymorphism: Possible largest Y chromosome in man?

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, D.S.K.; Al-Awadi, S.A.; Bastaki, L. [Kuwait Medical Genetics Centre, Sulaibikat (Kuwait)] [and others

    1994-09-01

    The role of variations (inversions/deletion or duplication) in the heterochromatin in gonadal development and function, reproductive fitness, and malignant disease has been extensively studied. However, the causal-relationship of large Y (Yqh+) and repeated fetal loss has not been established unequivocally. An Arab couple (?Bedouin origin) with a history of repeated abortions were investigated. Karyotype analysis of the husband showed a very large Y chromosome, confirmed by GTG-, QFQ- and CBG-banding techniques. C-banding showed discontinuous distribution of the heterochromatin blocks separated by pale bands. The origin of the large heterochromatin segment could be due to tandem duplication of the Yq region or translocation (Yq:Yq). No other relatives (males) of the propositus have been available for investigation. Polymorphism of the Y chromosome could be attributed to evolutionary changes from an ancestral type, either by deletion or duplication of the heterochromatin segment. More detailed studies on isolated, aboriginal/tribal human populations will enable us to better understand the significance of the Y chromosome polymorphism.

  12. Condensed matter physics

    International Nuclear Information System (INIS)

    The condensed matter physics research in the Physics Department of Risoe National Laboratory is predominantly experimental utilising diffraction of neutrons and x-rays. The research topics range from studies of structure, excitations and phase transitions in model systems to studies of ion transport, texture and recrystallization kinetics with a more applied nature. (author)

  13. DROPWISE CONDENSATION ON MICRO- AND NANOSTRUCTURED SURFACES

    Energy Technology Data Exchange (ETDEWEB)

    Enright, R; Miljkovic, N; Alvarado, JL; Kim, K; Rose, JW

    2014-07-23

    In this review we cover recent developments in the area of surface-enhanced dropwise condensation against the background of earlier work. The development of fabrication techniques to create surface structures at the micro-and nanoscale using both bottom-up and top-down approaches has led to increased study of complex interfacial phenomena. In the heat transfer community, researchers have been extensively exploring the use of advanced surface structuring techniques to enhance phase-change heat transfer processes. In particular, the field of vapor-to-liquid condensation and especially that of water condensation has experienced a renaissance due to the promise of further optimizing this process at the micro-and nanoscale by exploiting advances in surface engineering developed over the last several decades.

  14. Condensation heat transfer coefficient versus wettability

    Science.gov (United States)

    Roudgar, M.; De Coninck, J.

    2015-05-01

    In this paper we show how condensation on substrates can induce wetting behavior that is quite different from that of deposited or impinging drops. We describe surfaces with the same wettability in ambient conditions presenting different wetting behavior and growth of droplets in condensation. The experimental results show a rapid spread of droplets and formation of the film on the copper surface, while droplets on SU-8 surface remains on the regular shape while they grow within the time, without coalescence, as observed for Cu. Although the heat conductivity of SU-8 is much lower, due to a difference in wetting behavior, the heat transfer coefficient (h) is higher for dropwise condensation on Cu with a thin layer of SU-8 than filmwise on the bare copper.

  15. Sequential cloning of chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Lacks, S.A.

    1991-12-31

    A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  16. A high-resolution physical map integrating an anchored chromosome with the BAC physical maps of wheat chromosome 6B

    OpenAIRE

    Kobayashi, F; Wu, J. Z.; Kanamori, H; Tanaka, T.; Katagiri, S.; Karasawa, W.; Kaneko, S.; Watanabe, S; Sakaguchi, T; Šafář, J. (Jan); Šimková, H. (Hana); Mukai, Y.; M. Hamada; Saito, M; Hayakawa, K

    2015-01-01

    Background: A complete genome sequence is an essential tool for the genetic improvement of wheat. Because the wheat genome is large, highly repetitive and complex due to its allohexaploid nature, the International Wheat Genome Sequencing Consortium (IWGSC) chose a strategy that involves constructing bacterial artificial chromosome (BAC)-based physical maps of individual chromosomes and performing BAC-by-BAC sequencing. Here, we report the construction of a physical map of chromosome 6B with t...

  17. Incoherent scattering of light by a Bose--Einstein condensate of interacting atoms

    OpenAIRE

    Mazets, I. E.

    2000-01-01

    We demonstrate that incoherent photon scattering by a Bose-Einstein condensate of non-ideal atomic gas is enhanced due to bosonic stimulation of spontaneous emission, similarly to coherent scattering in forward direction. Necessary initial population of non-condensate states is provided by quantum depletion of a condensate caused by interatomic repulsion.

  18. CHROMOSOMES OF AMERICAN MARSUPIALS.

    Science.gov (United States)

    BIGGERS, J D; FRITZ, H I; HARE, W C; MCFEELY, R A

    1965-06-18

    Studies of the chromosomes of four American marsupials demonstrated that Caluromys derbianus and Marmosa mexicana have a diploid number of 14 chromosomes, and that Philander opossum and Didelphis marsupialis have a diploid number of 22. The karyotypes of C. derbianus and M. mexicana are similar, whereas those of P. opossum and D. marsupialis are dissimilar. If the 14-chromosome karyotype represents a reduction from a primitive number of 22, these observations suggest that the change has occurred independently in the American and Australasian forms.

  19. Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma Irradiation in ATM or NBS Suppressed Human Fibroblast Cells

    Science.gov (United States)

    Hada, M.; Huff, J. L.; Patel, Z.; Pluth, J. M.; George, K. A.; Cucinotta, F. A.

    2009-01-01

    A detailed understanding of the biological effects of heavy nuclei is needed for space radiation protection and for cancer therapy. High-LET radiation produces more complex DNA lesions that may be non-repairable or that may require additional processing steps compared to endogenous DSBs, increasing the possibility of misrepair. Interplay between radiation sensitivity, dose, and radiation quality has not been studied extensively. Previously we studied chromosome aberrations induced by low- and high- LET radiation in several cell lines deficient in ATM (ataxia telangactasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. We found that the yields of both simple and complex chromosomal aberrations were significantly increased in the DSB repair defective cells compared to normal cells. The increased aberrations observed for the ATM and NBS defective lines was due to a significantly larger quadratic dose-response term compared to normal fibroblasts for both simple and complex aberrations, while the linear dose-response term was significantly higher in NBS cells only for simple exchanges. These results point to the importance of the functions of ATM and NBS in chromatin modifications that function to facilitate correct DSB repair and minimize aberration formation. To further understand the sensitivity differences that were observed in ATM and NBS deficient cells, in this study, chromosomal aberration analysis was performed in normal lung fibroblast cells treated with KU-55933, a specific ATM kinase inhibitor, or Mirin, an MRN complex inhibitor involved in activation of ATM. We are also testing siRNA knockdown of these proteins. Normal and ATM or NBS suppressed cells were irradiated with gamma-rays and chromosomes were collected with a premature chromosome

  20. Small Supernumerary Marker Chromosomes in Human Infertility.

    Science.gov (United States)

    Armanet, Narjes; Tosca, Lucie; Brisset, Sophie; Liehr, Thomas; Tachdjian, Gérard

    2015-01-01

    Small supernumerary marker chromosomes (sSMC) are structurally abnormal chromosomes that cannot be unambiguously identified by banding cytogenetics. The objective of this study was to provide an overview of sSMC frequency and characterization in a context of infertility and to review the literature describing sSMC in relation with male and female infertility. Therefore, a systematic literature review on sSMC associated with infertility was conducted by means of a PubMed literature and a sSMC database (http://ssmc-tl.com/sSMC.html) search. A total of 234 patients with infertility were identified as carriers of sSMC. All chromosomes, except chromosomes 10, 19 and the X, were involved in sSMC, and in 72% the sSMC originated from acrocentric chromosomes. Euchromatic imbalances were caused by the presence of sSMC in 30% of the cases. Putative genes have been identified in only 1.2% of sSMC associated with infertility. The implication of sSMC in infertility could be due to a partial trisomy of some genes but also to mechanical effects perturbing meiosis. Further precise molecular and interphase-architecture studies on sSMC are needed in the future to characterize the relationship between this chromosomal anomaly and human infertility.

  1. Chromosomal abnormalities in patients with sperm disorders

    Directory of Open Access Journals (Sweden)

    L. Y. Pylyp

    2013-02-01

    Full Text Available Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intracytoplasmic sperm injection in particular, enable the transmission of chromosomal abnormalities to the progeny. Therefore, cytogenetic studies are important in patients with male factor infertility before assisted reproduction treatment. The purpose of the current study was to investigate the types and frequencies of chromosomal abnormalities in 724 patients with infertility and to estimate the risk of chromosomal abnormalities detection in subgroups of patients depending on the severity of spermatogenic disruption, aiming at identifying groups of patients in need of cytogenetic studies. Karyotype analysis was performed in 724 blood samples of men attending infertility clinic. Chromosomal preparation was performed by standard techniques. At least 20 GTG-banded metaphase plates with the resolution from 450 to 750 bands per haploid set were analysed in each case. When chromosomal mosaicism was suspected, this number was increased to 50. Abnormal karyotypes were observed in 48 (6.6% patients, including 67% of autosomal abnormalities and 33% of gonosomal abnormalities. Autosomal abnormalities were represented by structural rearrangements. Reciprocal translocations were the most common type of structural chromosomal abnormalities in the studied group, detected with the frequency of 2.6% (n = 19, followed by Robertsonian translocation, observed with the frequency of 1.2% (n = 9. The frequency of inversions was 0.6% (n = 4. Gonosomal abnormalities included 14 cases

  2. Photon condensation: A new paradigm for Bose-Einstein condensation

    Science.gov (United States)

    Rajan, Renju; Ramesh Babu, P.; Senthilnathan, K.

    2016-10-01

    Bose-Einstein condensation is a state of matter known to be responsible for peculiar properties exhibited by superfluid Helium-4 and superconductors. Bose-Einstein condensate (BEC) in its pure form is realizable with alkali atoms under ultra-cold temperatures. In this paper, we review the experimental scheme that demonstrates the atomic Bose-Einstein condensate. We also elaborate on the theoretical framework for atomic Bose-Einstein condensation, which includes statistical mechanics and the Gross-Pitaevskii equation. As an extension, we discuss Bose-Einstein condensation of photons realized in a fluorescent dye filled optical microcavity. We analyze this phenomenon based on the generalized Planck's law in statistical mechanics. Further, a comparison is made between photon condensate and laser. We describe how photon condensate may be a possible alternative for lasers since it does not require an energy consuming population inversion process.

  3. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  4. Chromosomal Abnormalties with Epilepsy

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-02-01

    Full Text Available The correlation between specific chromosome abnormalties and various epilepsies was investigated by a study of 76 patients’ records obtained by questionnaires distributed to members of Kyoto Multi-institutional Study Group of Pediatric Neurology.

  5. Recondensation phenomena of a hot two-phase fluid in the presence of non condensable gases

    International Nuclear Information System (INIS)

    The condensation rates obtained during the expansion of a large hot bubble containing non condensable gases in its cold liquid is studied. The failure of theories derived from the Nusselt model for liquid metals led to use the kinetic theory of condensation. The additionnal resistance due to the presence of non condensable gases is expressed by the vapor diffusion through the layer of gases which accumulates at the interface. This model is then used to interprete experiments

  6. Chimpanzee chromosome 13 is homologous to human chromosome 2p

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Similarities between human and chimpanzee chromosomes are shown by chromosome banding techniques and somatic cell hybridization techniques. Cell hybrids were obtained from the chimpanzee lymphocyte LE-7, and the Chinese hamster mutant cell, Gal-2. Experiments showed that the ACPL, MDHs, and Gal-Act genes could be assigned to chimpanzee chromosome 13, and since these genes have been assigned to human chromosme 2p, it is suggested that chimpanzee chromosome 13 is homologous to human chromosome 2p. (HLW)

  7. Chromosome doubling method

    Science.gov (United States)

    Kato, Akio

    2006-11-14

    The invention provides methods for chromosome doubling in plants. The technique overcomes the low yields of doubled progeny associated with the use of prior techniques for doubling chromosomes in plants such as grasses. The technique can be used in large scale applications and has been demonstrated to be highly effective in maize. Following treatment in accordance with the invention, plants remain amenable to self fertilization, thereby allowing the efficient isolation of doubled progeny plants.

  8. Multilayer graphene condenser microphone

    Science.gov (United States)

    Todorović, Dejan; Matković, Aleksandar; Milićević, Marijana; Jovanović, Djordje; Gajić, Radoš; Salom, Iva; Spasenović, Marko

    2015-12-01

    Vibrating membranes are the cornerstone of acoustic technology, forming the backbone of modern loudspeakers and microphones. Acoustic performance of a condenser microphone is derived mainly from the membrane’s size, surface mass and achievable static tension. The widely studied and available nickel has been a dominant membrane material for professional microphones for several decades. In this paper we introduce multilayer graphene as a membrane material for condenser microphones. The graphene device outperforms a high end commercial nickel-based microphone over a significant part of the audio spectrum, with a larger than 10 dB enhancement of sensitivity. Our experimental results are supported with numerical simulations, which also show that a 300 layer thick graphene membrane under maximum tension would offer excellent extension of the frequency range, up to 1 MHz.

  9. Condensed matter physics

    CERN Document Server

    Marder, Michael P

    2010-01-01

    This Second Edition presents an updated review of the whole field of condensed matter physics. It consolidates new and classic topics from disparate sources, teaching not only about the effective masses of electrons in semiconductor crystals and band theory, but also about quasicrystals, dynamics of phase separation, why rubber is more floppy than steel, granular materials, quantum dots, Berry phases, the quantum Hall effect, and Luttinger liquids.

  10. Micromechanics of human mitotic chromosomes

    International Nuclear Information System (INIS)

    Eukaryote cells dramatically reorganize their long chromosomal DNAs to facilitate their physical segregation during mitosis. The internal organization of folded mitotic chromosomes remains a basic mystery of cell biology; its understanding would likely shed light on how chromosomes are separated from one another as well as into chromosome structure between cell divisions. We report biophysical experiments on single mitotic chromosomes from human cells, where we combine micromanipulation, nano-Newton-scale force measurement and biochemical treatments to study chromosome connectivity and topology. Results are in accord with previous experiments on amphibian chromosomes and support the 'chromatin network' model of mitotic chromosome structure. Prospects for studies of chromosome-organizing proteins using siRNA expression knockdowns, as well as for differential studies of chromosomes with and without mutations associated with genetic diseases, are also discussed

  11. Asymmetric condensed dark matter

    Science.gov (United States)

    Aguirre, Anthony; Diez-Tejedor, Alberto

    2016-04-01

    We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component would develop a Bose-Einstein condensate in the early universe that, for appropriate model parameters, could survive the ensuing cosmological evolution until now. The condensation of a dark matter component in equilibrium with the thermal plasma is a relativistic process, hence the amount of matter dictated by the charge asymmetry is complemented by a hot relic density frozen out at the time of decoupling. Contrary to the case of ordinary WIMPs, dark matter particles in a condensate must be lighter than a few tens of eV so that the density from thermal relics is not too large. Big-Bang nucleosynthesis constrains the temperature of decoupling to the scale of the QCD phase transition or above. This requires large dark matter-to-photon ratios and very weak interactions with standard model particles.

  12. Temporal dynamics of Bose-condensed gases

    Energy Technology Data Exchange (ETDEWEB)

    Trujillo Martinez, Mauricio

    2014-03-19

    We perform a detailed quantum dynamical study of non-equilibrium trapped, interacting Bose-condensed gases. We investigate Josephson oscillations between interacting Bose-Einstein condensates confined in a finite size double-well trap and the non-trivial time evolution of a coherent state placed at the center of a two dimensional optical lattice. For the Josephson oscillations three time scales appear. We find that Josephson junction can sustain multiple undamped oscillations up to a characteristic time scale τ{sub c} without exciting atoms out of the condensates. Beyond the characteristic time scale τ{sub c} the dynamics of the junction are governed by fast, non-condensed particles assisted Josephson tunnelling as well as the collisions between non-condensed particles. In the non-condensed particles dominated regime we observe strong damping of the oscillations due to inelastic collisions, equilibrating the system leading to an effective loss of details of the initial conditions. In addition, we predict that an initially self-trapped BEC state will be destroyed by these fast dynamics. The time evolution of a coherent state released at the center of a two dimensional optical lattice shows a ballistic expansion with a decreasing expansion velocity for increasing two-body interactions strength and particle number. Additionally, we predict that if the two-body interactions strength exceeds a certain value, a forerunner splits up from the expanding coherent state. We also observe that this system, which is prepared far from equilibrium, can evolve to a quasistationary non-equilibrium state.

  13. Dark matter as a condensate: Deduction of microscopic properties

    CERN Document Server

    Gutierrez, Sergio; Camacho, Abel

    2016-01-01

    In the present work we model dark matter as a Bose-Einstein condensate and the main goal is the deduction of the microscopic properties, namely, mass, number of particles, and scattering length, related to the particles comprised in the corresponding condensate. This task is done introducing in the corresponding model the effects of the thermal cloud of the system. Three physical conditions are imposed, i.e., mechanical equilibrium of the condensate, explanation of the rotation curves of stars belonging to dwarf galaxies, and, finally, the deflection of light due to the presence of dark matter. These three aforementioned expressions allow us to cast the features of the particles in terms of detectable astrophysical variables. Finally, the model is contrasted against observational data and in this manner we obtain values for the involved microscopic parameters of the condensate. The deduced results are compared with previous results in which dark matter has not been considered a condensate. The main conclusion...

  14. Biodosimetry of heavy ions by interphase chromosome painting

    Science.gov (United States)

    Durante, M.; Kawata, T.; Nakano, T.; Yamada, S.; Tsujii, H.

    1998-11-01

    We report measurements of chromosomal aberrations in peripheral blood lymphocytes from cancer patients undergoing radiotherapy treatment. Patients with cervix or esophageal cancer were treated with 10 MV X-rays produced at a LINAC accelerator, or high-energy carbon ions produced at the HIMAC accelerator at the National Institute for Radiological Sciences (NIRS) in Chiba. Blood samples were obtained before, during, and after the radiation treatment. Chromosomes were prematurely condensed by incubation in calyculin A. Aberrations in chromosomes 2 and 4 were scored after fluorescence in situ hybridization with whole-chromosome probes. Pre-treatment samples were exposed in vitro to X-rays, individual dose-response curves for the induction of chromosomal aberrations were determined, and used as calibration curves to calculate the effective whole-body dose absorbed during the treatment. This calculated dose, based on the calibration curve relative to the induction of reciprocal exchanges, has a sharp increase after the first few fractions of the treatment, then saturates at high doses. Although carbon ions are 2-3 times more effective than X-rays in tumor sterilization, the effective dose was similar to that of X-ray treatment. However, the frequency of complex-type chromosomal exchanges was much higher for patients treated with carbon ions than X-ray.

  15. Ancient Male Recombination Shaped Genetic Diversity of Neo-Y Chromosome in Drosophila albomicans.

    Science.gov (United States)

    Satomura, Kazuhiro; Tamura, Koichiro

    2016-02-01

    Researchers studying Y chromosome evolution have drawn attention to neo-Y chromosomes in Drosophila species due to their resembling the initial stage of Y chromosome evolution. In the studies of neo-Y chromosome of Drosophila miranda, the extremely low genetic diversity observed suggested various modes of natural selection acting on the nonrecombining genome. However, alternative possibility may come from its peculiar origin from a single chromosomal fusion event with male achiasmy, which potentially caused and maintained the low genetic diversity of the neo-Y chromosome. Here, we report a real case where a neo-Y chromosome is in transition from an autosome to a typical Y chromosome. The neo-Y chromosome of Drosophila albomicans harbored a rich genetic diversity comparable to its gametologous neo-X chromosome and an autosome in the same genome. Analyzing sequence variations in 53 genes and measuring recombination rates between pairs of loci by cross experiments, we elucidated the evolutionary scenario of the neo-Y chromosome of D. albomicans having high genetic diversity without assuming selective force, i.e., it originated from a single chromosomal fusion event, experienced meiotic recombination during the initial stage of evolution and diverged from neo-X chromosome by the suppression of recombination tens or a few hundreds of thousand years ago. Consequently, the observed high genetic diversity on the neo-Y chromosome suggested a strong effect of meiotic recombination to introduce genetic variations into the newly arisen sex chromosome. PMID:26494844

  16. Chromokinesin: Kinesin superfamily regulating cell division through chromosome and spindle.

    Science.gov (United States)

    Zhong, Ai; Tan, Fu-Qing; Yang, Wan-Xi

    2016-09-01

    Material transportation is essential for appropriate cellular morphology and functions, especially during cell division. As a motor protein moving along microtubules, kinesin has several intracellular functions. Many kinesins play important roles in chromosome condensation and separation and spindle organization during the cell cycle. Some of them even can directly bind to chromosomes, as a result, these proteins are called chromokinesins. Kinesin-4 and kinesin-10 family are two major families of chromokinesin and many members can regulate some processes, both in mitosis and meiosis. Their functions have been widely studied. Here, we summarize current knowledge about known chromokinesins and introduce their intracellular features in accordance with different families. Furthermore, we have also introduced some new-found but unconfirmed kinesins which may have a relationship with chromosomes or the cell cycle. PMID:27196062

  17. Stacked thin layers of metaphase chromatin explain the geometry of chromosome rearrangements and banding.

    Science.gov (United States)

    Daban, Joan-Ramon

    2015-10-08

    The three-dimensional organization of tightly condensed chromatin within metaphase chromosomes has been one of the most challenging problems in structural biology since the discovery of the nucleosome. This study shows that chromosome images obtained from typical banded karyotypes and from different multicolour cytogenetic analyses can be used to gain information about the internal structure of chromosomes. Chromatin bands and the connection surfaces in sister chromatid exchanges and in cancer translocations are planar and orthogonal to the chromosome axis. Chromosome stretching produces band splitting and even the thinnest bands are orthogonal and well defined, indicating that short stretches of DNA can occupy completely the chromosome cross-section. These observations impose strong physical constraints on models that attempt to explain chromatin folding in chromosomes. The thin-plate model, which consists of many stacked layers of planar chromatin perpendicular to the chromosome axis, is compatible with the observed orientation of bands, with the existence of thin bands, and with band splitting; it is also compatible with the orthogonal orientation and planar geometry of the connection surfaces in chromosome rearrangements. The results obtained provide a consistent interpretation of the chromosome structural properties that are used in clinical cytogenetics for the diagnosis of hereditary diseases and cancers.

  18. Convective condensation heat transfer in a horizontal condenser tube

    Energy Technology Data Exchange (ETDEWEB)

    Sarma, P.K. [College of Engineering, GITAM, Visakhapatnam (India); Sastry, C.V.N.; Rao, V.D. [Andhra Univ., College of Engineering, Visakhapatnam (India); Kakac, S.; Liu, H. [Miami Univ., College of Engineering, FL (United States)

    2002-03-01

    The purpose of this article is to solve analytically the problem of convective condensation of vapors inside a horizontal condenser tube. Homogeneous model approach is employed in the estimation of shear velocity, which is subsequently, made use of in predicting local convective condensation heat transfer coefficients. The resulting analysis of the present study is compared with some of the available equations in the literature. It is observed that the agreement is reasonably satisfactory validating the assumptions and the theory presented. (authors)

  19. Soft Condensed Matter

    International Nuclear Information System (INIS)

    The author states in the preface of the book that the aim is '...to give a unified overview of the various aspects of the physics of soft condensed matter'. The book succeeds in fulfilling this aim in many respects. The style is fluent and concise and gives the necessary explanations to make its content understandable to people with some knowledge of the basic principles of physics. The content of the book is complete enough to give a panoramic view of the landscape of soft condensed matter. The first two chapters give, respectively, a short introduction and a presentation of forces, energies and timescales, giving a general overview and pointing out the particular importance of different aspects such as timescales, which are much more important in soft condensed matter than in traditional or 'hard' condensed matter. The next chapter, devoted to phase transition, recalls that the equilibrium between two phases is controlled by free energy considerations. Spinodal decomposition is presented as a counterpart of nucleation and growth. Again, characteristic length scales are considered and applied to a phase separation mixture of polymers in a common solvent. The following three chapters are devoted respectively to specific topics: colloidal dispersion, polymers and gelation. The stability and phase behaviour of colloids are related to the interaction between colloidal particles. Properties of colloidal crystals as well as colloidal dispersion are depicted in terms of stabilization of crystalline colloids. The flow properties of colloidal dispersion are presented in terms of free energy minimization and the structure of the dispersion. After a brief introduction to polymer chemistry and architecture, the coil-globule transition is discussed. Viscoelasticity of polymers is described and discussed by introducing the notion of entanglement. This leads to the introduction of the tube model and the theory of reptation. The sol-gel transition is presented phenomenologically

  20. CONDENSATION OF WATER VAPOR IN A VERTICAL TUBE CONDENSER

    OpenAIRE

    Jan Havlík; Tomáš Dlouhý

    2015-01-01

    This paper presents an analysis of heat transfer in the process of condensation of water vapor in a vertical shell-and-tube condenser. We analyze the use of the Nusselt model for calculating the condensation heat transfer coefficient (HTC) inside a vertical tube and the Kern, Bell-Delaware and Stream-flow analysis methods for calculating the shell-side HTC from tubes to cooling water. These methods are experimentally verified for a specific condenser of waste process vapor containing air. The...

  1. Spinor condensates and light scattering from Bose-Einstein condensates

    International Nuclear Information System (INIS)

    These notes discuss-two aspects of the physics of atomic Bose-Einstein condensates: optical properties and spinor condensates. The first topic includes light scattering experiments which probe the excitations of a condensate in both the free-particle and phonon regime. At higher light intensity, a new form of superradiance and phase-coherent matter wave amplification were observed. We also discuss properties of spinor condensates and describe studies of ground-state spin domain structures and dynamical studies which revealed metastable excited states and quantum tunneling. (authors)

  2. Modeling and Optimization of Superhydrophobic Condensation

    OpenAIRE

    Miljkovic, Nenad; Enright, Ryan; Wang, Evelyn N.

    2012-01-01

    Superhydrophobic micro/nanostructured surfaces for dropwise condensation have recently received significant attention due to their potential to enhance heat transfer performance by shedding water droplets via coalescence-induced droplet jumping at length scales below the capillary length. However, achieving optimal surface designs for such behavior requires capturing the details of transport processes that is currently lacking. While comprehensive models have been developed for flat hydrophob...

  3. Thermal condensation mode in a dusty plasma

    Indian Academy of Sciences (India)

    B P Pandey; J Vranješ; S Parhi

    2003-03-01

    In the present work, the radiative condensation instability is investigated in the presence of dust charge fluctuations. We find that the charge variability of the grain reduces the growth rate of radiative mode only for fluctuation wavelength smaller or of the order of the Debye length and this reduction is not very large. Far from the Debye sphere, radiative mode can damp due to thermal conduction of electrons and ions.

  4. Condensed landscape experience

    DEFF Research Database (Denmark)

    Earon, Ofri

    2011-01-01

    demands, quality of space, mixture of functions, urban complexity, public life and cultural heritage. In order to launch such an approach, an understanding of the spatial, social and environmental significance of a radical re-thinking of relationships between architecture and landscape is necessary....... This paper addresses the question of whether the sensation of landscape can be condensed in function or to the size of an urban building. It also discusses the benefits and potentials of the amalgamate, by underlining the unique qualities of such a hybrid. In an attempt to define the experience of landscape...

  5. The condensed matter physics

    International Nuclear Information System (INIS)

    The 1988 progress report of the laboratory of the Condensed Matter Physics (Polytechnic School, France), is presented. The Laboratory activities are related to the physics of semiconductors and disordered phases. The electrical and optical properties of the semiconductors, mixed conductor, superionic conductors and ceramics, are studied. Moreover, the interfaces of those systems and the sol-gel inorganic polymerization phenomena, are investigated. The most important results obtained, concern the following investigations: the electrochemical field effect transistor, the cathodoluminescence, the low energy secondary electrons emission, the fluctuations of a two-dimensional diffused junction and the aerogels

  6. Confinement Contains Condensates

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, Stanley J.; Roberts, Craig D.; Shrock, Robert; Tandy, Peter C.

    2012-03-12

    Dynamical chiral symmetry breaking and its connection to the generation of hadron masses has historically been viewed as a vacuum phenomenon. We argue that confinement makes such a position untenable. If quark-hadron duality is a reality in QCD, then condensates, those quantities that have commonly been viewed as constant empirical mass-scales that fill all spacetime, are instead wholly contained within hadrons; i.e., they are a property of hadrons themselves and expressed, e.g., in their Bethe-Salpeter or light-front wave functions. We explain that this paradigm is consistent with empirical evidence, and incidentally expose misconceptions in a recent Comment.

  7. Orientation Dependence of Jumping Droplet Condensation

    Science.gov (United States)

    Berrier, Austin; Boreyko, Jonathan; Nature-Inspired Fluids; Interfaces Team

    2015-11-01

    On nanostructured superhydrophobic surfaces, microscopic condensate exhibits out-of-plane jumping that minimizes the average droplet size for maximal phase-change heat transfer. This jumping-droplet phenomenon occurs independently of gravity and is due to surface energy being partially converted to kinetic energy upon coalescence events. Although the initial departure of the jumping droplets is independent of gravity, the subsequent trajectories exhibit a dependence upon the orientation of the substrate. The drop size distribution of jumping-droplet condensation growing on a superhydrophobic substrate was characterized for both horizontal and vertical surface orientations. With the horizontal orientation, jumping condensate returns to the substrate by gravity. While this can result in chain reactions with other droplets to trigger further jumping events, eventually the rebounding droplets become too large to jump and are stuck on the surface. In contrast, droplets jumping off a vertically oriented surface do not return to the substrate. For this reason, the maximum droplet diameters during condensation growth were found to be significantly larger on the horizontally oriented superhydrophobic surface than on the vertical orientation.

  8. Chromosome numbers in Bromeliaceae

    Directory of Open Access Journals (Sweden)

    Cotias-de-Oliveira Ana Lúcia Pires

    2000-01-01

    Full Text Available The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. utriculosa. The chromosome number of all species was determined for the first time, except for Billbergia chlorosticta and Cryptanthus bahianus. Our data supports the hypothesis of a basic number of x = 25 for the Bromeliaceae family and decreasing aneuploidy in the genus Cryptanthus.

  9. Those amazing dinoflagellate chromosomes

    Institute of Scientific and Technical Information of China (English)

    PETER J RIZZO

    2003-01-01

    Dinoflagellates are a very large and diverse group of eukaryotic algae that play a major role in aquatic food webs of both fresh water and marine habitats. Moreover, the toxic members of this group pose a health threat in the form of red tides. Finally, dinoflagellates are of great evolutionary importance,because of their taxonomic position, and their unusual chromosome structure and composition. While the cytoplasm of dinoflagellates is typically eukaryotic, the nucleus is unique when compared to the nucleus of other eukaryotes. More specifically, while the chromosomes of all other eukaryotes contain histones,dinoflagellate chromosomes lack histones completely. There are no known exceptions to this observation: all dinoflagellates lack histones, and all other eukaryotes contain histones. Nevertheless, dinoflagellates remain a relatively unstudied group of eukaryotes.

  10. Extraction of condensed tannins from Mexican plant sources.

    Science.gov (United States)

    Garcíaa, Ramiro; Aguilera, Antonio; Contreras-Esquivel, Juan C; Rodríguez, Raúl; Aguilar, Cristóbal N

    2008-01-01

    Contents of total polyphenols, condensed tannins and proanthocyanidins, and their stability to various pH values and temperatures were studied in Mexican blueberry, cuautecomate fruit, garambullo fruit, aubergine, coffee pulp and residues of black grapes. Several aqueous extracts, obtained through a one-pass-extraction process, were analyzed using liquid chromatography in order to quantify the condensed tannin (proanthocyanidin) content responsible for their antioxidant activity and colour. All tested samples included high proanthocyanidin contents demonstrating that these Mexican fruits and vegetables are good sources of natural antioxidants, and they all could be considered as excellent functional foods due to their bioactivity measured as the condensed tannin level.

  11. Condensate losses and oscillations induced by Rydberg atoms

    CERN Document Server

    Karpiuk, Tomasz; Rzążewski, Kazimierz; Gaj, Anita; Krupp, Alexander T; Löw, Robert; Hofferberth, Sebastian; Pfau, Tilman

    2016-01-01

    We numerically analyze the impact of a single Rydberg electron onto a Bose-Einstein condensate. Both $S-$ and $D-$ Rydberg states are studied. The radial size of $S-$ and $D-$states are comparable, hence the only difference is due to the angular dependence of the wavefunctions. We find the atom losses in the condensate after the excitation of a sequence of Rydberg atoms. Additionally, we investigate the mechanical effect in which the Rydberg atoms force the condensate to oscillate. Our numerical analysis is based on the classical fields approximation. Finally, we compare numerical results to experimental data.

  12. Chromosomal polymorphism in the Sporothrix schenckii complex.

    Science.gov (United States)

    Sasaki, Alexandre A; Fernandes, Geisa F; Rodrigues, Anderson M; Lima, Fábio M; Marini, Marjorie M; Dos S Feitosa, Luciano; de Melo Teixeira, Marcus; Felipe, Maria Sueli Soares; da Silveira, José Franco; de Camargo, Zoilo P

    2014-01-01

    Sporotrichosis is a polymorphic disease caused by a complex of thermodimorphic fungi including S. brasiliensis, S. schenckii sensu stricto (s. str.), S. globosa and S. luriei. Humans and animals can acquire the disease through traumatic inoculation of propagules into the subcutaneous tissue. Despite the importance of sporotrichosis as a disease that can take epidemic proportions there are just a few studies dealing with genetic polymorphisms and genomic architecture of these pathogens. The main objective of this study was to investigate chromosomal polymorphisms and genomic organization among different isolates in the S. schenckii complex. We used pulsed field gel electrophoresis (PFGE) to separate chromosomal fragments of isolated DNA, followed by probe hybridization. Nine loci (β-tubulin, calmodulin, catalase, chitin synthase 1, Internal Transcribed Spacer, Pho85 cyclin-dependent kinase, protein kinase C Ss-2, G protein α subunit and topoisomerase II) were mapped onto chromosomal bands of Brazilian isolates of S. schenckii s. str. and S. brasiliensis. Our results revealed the presence of intra and interspecies polymorphisms in chromosome number and size. The gene hybridization analysis showed that closely related species in phylogenetic analysis had similar genetic organizations, mostly due to identification of synteny groups in chromosomal bands of similar sizes. Our results bring new insights into the genetic diversity and genome organization among pathogenic species in the Sporothrix schenckii complex.

  13. Analysis of transition state theory for condensation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    By statistically analyzing the condensation process and reconsidering the transition state theory for condensation and evaporation, we first presented a completed theoretical formula of the condensation coefficient. Namely, the unknown parameters contained within the transition state theoretical calculation of the condensation coefficient are determined. The condensation coefficients calculated from this formula agree well with those from molecular dynamics simulations. With this formula, the classical expression of the condensation flux developed from the gas kinetic theory can be used to predict the condensation flux.

  14. Heavy ion-induced chromosomal aberrations analyzed by fluorescence in situ hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Durante, M.; Gialanella, G.; Grossi, G.; Pugliese, M. [Univ. ``Federico II``, Naples (Italy). Dept. of Physics]|[INFN, Naples (Italy); Cella, L.; Greco, O. [Univ. ``Federico II``, Naples (Italy). Dept. of Physics; Furusawa, Y. [NIRS, Chiba (Japan); George, K.; Yang, T.C. [NASA Lyndon B. Johnson Space Center, Houston, TX (United States)

    1997-09-01

    We have investigated the effectiveness of heavy ions in the induction of chromosomal aberrations in mammalian cells by the recent technique of fluorescence in situ hybridization (FISH) with whole-chromosome probes. FISH-painting was used both in metaphase and interphase (prematurely condensed) chromosomes. The purpose of our experiments was to address the following problems: (a) the ratio of different types of aberrations as a function of radiation quality (search for biomarkers); (b) the ratio between aberrations scored in interphase and metaphase as a function of radiation quality (role of apoptosis); (c) differences between cytogenetic effects produced by different ions at the same LET (role of track structure). (orig./MG)

  15. Quantitative assessment of DNA condensation.

    Science.gov (United States)

    Trubetskoy, V S; Slattum, P M; Hagstrom, J E; Wolff, J A; Budker, V G

    1999-02-15

    A fluorescent method is proposed for assessing DNA condensation in aqueous solutions with variety of condensing agents. The technique is based on the effect of concentration-dependent self-quenching of covalently bound fluorophores upon DNA collapse. The method allows a more precise determination of charge equivalency in titration experiments with various polycations. The technique's ability to determine the number of DNA molecules that are condensed together in close proximity is under further investigation.

  16. Molecular cytogenetic studies in structural abnormalities of chromosome 13

    Energy Technology Data Exchange (ETDEWEB)

    Lozzio, C.B.; Bamberger, E.; Anderson, I. [Univ. of Tennessee, Knoxville, TN (United States)] [and others

    1994-09-01

    A partial trisomy 13 was detected prenatally in an amniocentesis performed due to the following ultrasound abnormalities: open sacral neural tube defect (NTD), a flattened cerebellum, and lumbar/thoracic hemivertebrae. Elevated AFP and positive acetylcholinesterase in amniotic fluid confirmed the open NTD. Chromosome analysis showed an extra acrocentric chromosome marker. FISH analysis with the painting probe 13 showed that most of the marker was derived from this chromosome. Chromosomes on the parents revealed that the mother had a balanced reciprocal translocation t(2;13)(q23;q21). Dual labeling with painting chromosomes 2 and 13 on cells from the mother and from the amniotic fluid identified the marker as a der(13)t(2;13)(p23;q21). Thus, the fetus had a partial trisomy 13 and a small partial trisomy 2p. The maternal grandfather was found to be a carrier for this translocation. Fetal demise occurred a 29 weeks of gestation. The fetus had open lumbar NTD and showed dysmorphic features, overlapping fingers and imperforate anus. This woman had a subsequent pregnancy and chorionic villi sample showed that this fetus was normal. Another case with an abnormal chromosome 13 was a newborn with partial monosomy 13 due to the presence of a ring chromosome 13. This infant had severe intrauterine growth retardation, oligohydramnios, dysmorphic features and multiple congenital microphthalmia, congenital heart disease, absent thumbs and toes and cervical vertebral anomalies. Chromosome studies in blood and skin fibroblast cultures showed that one chromosome 3 was replaced by a ring chromosome of various sizes. This ring was confirmed to be derived from chromosome 13 using the centromeric 21/13 probe.

  17. Karyotype evolution in apomictic Boechera and the origin of the aberrant chromosomes.

    Science.gov (United States)

    Mandáková, Terezie; Schranz, M Eric; Sharbel, Timothy F; de Jong, Hans; Lysak, Martin A

    2015-06-01

    Chromosome rearrangements may result in both decrease and increase of chromosome numbers. Here we have used comparative chromosome painting (CCP) to reconstruct the pathways of descending and ascending dysploidy in the genus Boechera (tribe Boechereae, Brassicaceae). We describe the origin and structure of three Boechera genomes and establish the origin of the previously described aberrant Het and Del chromosomes found in Boechera apomicts with euploid (2n = 14) and aneuploid (2n = 15) chromosome number. CCP analysis allowed us to reconstruct the origin of seven chromosomes in sexual B. stricta and apomictic B. divaricarpa from the ancestral karyotype (n = 8) of Brassicaceae lineage I. Whereas three chromosomes (BS4, BS6, and BS7) retained their ancestral structure, five chromosomes were reshuffled by reciprocal translocations to form chromosomes BS1-BS3 and BS5. The reduction of the chromosome number (from x = 8 to x = 7) was accomplished through the inactivation of a paleocentromere on chromosome BS5. In apomictic 2n = 14 plants, CCP identifies the largely heterochromatic chromosome (Het) being one of the BS1 homologues with the expansion of pericentromeric heterochromatin. In apomictic B. polyantha (2n = 15), the Het has undergone a centric fission resulting in two smaller chromosomes - the submetacentric Het' and telocentric Del. Here we show that new chromosomes can be formed by a centric fission and can be fixed in populations due to the apomictic mode of reproduction.

  18. Production of a chromium Bose-Einstein condensate

    OpenAIRE

    Griesmaier, Axel; Stuhler, Jürgen; Pfau, Tilman

    2005-01-01

    The recent achievement of Bose-Einstein condensation of chromium atoms [1] has opened longed-for experimental access to a degenerate quantum gas with long-range and anisotropic interaction. Due to the large magnetic moment of chromium atoms of 6 {$\\mu$}B, in contrast to other Bose- Einstein condensates (BECs), magnetic dipole-dipole interaction plays an important role in a chromium BEC. Many new physical properties of degenerate gases arising from these magnetic forces have been predicted in ...

  19. Stationary and nonstationary fluid flow of a bose-einstein condensate through a penetrable barrier.

    Science.gov (United States)

    Engels, P; Atherton, C

    2007-10-19

    We experimentally study the fluid flow induced by a broad, penetrable barrier moving through an elongated dilute gaseous Bose-Einstein condensate. The barrier is created by a laser beam swept through the condensate, and the resulting dipole potential can be either attractive or repulsive. We examine both cases and find regimes of stable and unstable fluid flow: At slow speeds of the barrier, the fluid flow is steady due to the superfluidity of the condensate. At intermediate speeds, we observe an unsteady regime in which the condensate gets filled with dark solitons. At faster speeds, soliton formation completely ceases, and a remarkable absence of excitation in the condensate is seen again.

  20. Chromosomal evolution among leaf-nosed nectarivorous bats – evidence from cross-species chromosome painting (Phyllostomidae, Chiroptera)

    Science.gov (United States)

    2013-01-01

    Background New World leaf-nosed bats, Phyllostomidae, represent a lineage of Chiroptera marked by unprecedented morphological/ecological diversity and extensive intergeneric chromosomal reorganization. There are still disagreements regarding their systematic relationships due to morphological convergence among some groups. Their history of karyotypic evolution also remains to be documented. Results To better understand the evolutionary relationships within Phyllostomidae, we developed chromosome paints from the bat species Macrotus californicus. We tested the potential of these paints as phylogenetic tools by looking for chromosomal signatures in two lineages of nectarivorous phyllostomids whose independent origins have been statistically supported by molecular phylogenies. By examining the chromosomal homologies defined by chromosome painting among two representatives of the subfamily Glossophaginae (Glossophaga soricina and Anoura cultrata) and one species from the subfamily Lonchophyllinae (Lonchophylla concava), we found chromosomal correspondence in regions not previously detected by other comparative cytogenetic techniques. We proposed the corresponding human chromosomal segments for chromosomes of the investigated species and found two syntenic associations shared by G. soricina and A. cultrata. Conclusion Comparative painting with whole chromosome-specific paints of M. californicus demonstrates an extensive chromosomal reorganization within the two lineages of nectarivorous phyllostomids, with a large number of chromosomes shared between M. californicus and G. soricina. We show that the evolution of nectar-feeding bats occurs mainly by reshuffling of chiropteran Evolutionarily Conserved Units (ECUs). Robertsonian fusions/fissions and inversions seem to be important modifiers of phyllostomid karyotypes, and autapomorphic character states are common within species. Macrotus californicus chromosome paints will be a valuable tool for documenting the pattern of

  1. The Y Chromosome

    Science.gov (United States)

    Offner, Susan

    2010-01-01

    The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

  2. Chromosomes, cancer and radiosensitivity

    International Nuclear Information System (INIS)

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available

  3. Chromosomes, cancer and radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Samouhos, E.

    1983-08-01

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available.

  4. Searching for Electrical Properties, Phenomena and Mechanisms in the Construction and Function of Chromosomes

    Directory of Open Access Journals (Sweden)

    Ivan Kanev

    2013-03-01

    Full Text Available Our studies reveal previously unidentified electrical properties of chromosomes: (1 chromosomes are amazingly similar in construction and function to electrical transformers; (2 chromosomes possess in their construction and function, components similar to those of electric generators, conductors, condensers, switches, and other components of electrical circuits; (3 chromosomes demonstrate in nano-scale level electromagnetic interactions, resonance, fusion and other phenomena similar to those described by equations in classical physics. These electrical properties and phenomena provide a possible explanation for unclear and poorly understood mechanisms in clinical genetics including: (a electrically based mechanisms responsible for breaks, translocations, fusions, and other chromosomal abnormalities associated with cancer, intellectual disability, infertility, pregnancy loss, Down syndrome, and other genetic disorders; (b electrically based mechanisms involved in crossing over, non-disjunction and other events during meiosis and mitosis; (c mechanisms demonstrating heterochromatin to be electrically active and genetically important.

  5. Nonequilibrium Weak Processes in Kaon Condensation; 2, Kinetics of condensation

    CERN Document Server

    Muto, T; Iwamoto, N; Muto, Takumi; Tatsumi, Toshitaka; Iwamoto, Naoki

    2000-01-01

    The kinetics of negatively charged kaon condensation in the early stages of a newly born neutron star is considered. The thermal kaon process, in which kaons are thermally produced by nucleon-nucleon collisions, is found to be dominant throughout the equilibration process. Temporal changes of the order parameter of the condensate and the number densities of the chemical species are obtained from the rate equations, which include the thermal kaon reactions as well as the kaon-induced Urca and the modified Urca reactions. It is shown that the dynamical evolution of the condensate is characterized by three stages: the first, prior to establishment of a condensate, the second, during the growth and subsequent saturation of the condensate, and the third, near chemical equilibrium. The connection between the existence of a soft kaon mode and the instability of the noncondensed state is discussed. Implications of the nonequilibrium process on the possible delayed collapse of a protoneutron star are also mentioned.

  6. Condensation Processes in Geothermal Systems

    Science.gov (United States)

    Norman, D. I.; Moore, J. N.

    2005-12-01

    We model condensation processes in geothermal systems to understand how this process changes fluid chemistry. We assume two processes operate in geothermal systems: 1) condensation of a vapor phase derived by boiling an aqueous geothermal fluid into a cool near surface water and 2) condensation of a magmatic vapor by a deep circulating meteoric thermal fluid. It is assumed that the condensation process has two stages. Initially the condensing fluid is under saturated in gaseous species. Condensation of the vapor phase continues until the pressure on the fluid equals the sum of the partial pressures of water and the dissolved gaseous species. At that time bubbles flux through the condensing fluid. In time the fluid and fluxing gas phase come to equilibrium. Calculation shows that during the second stage of the condensation process the liquid phase becomes enriched in more soluble gaseous species like CO2 and H2S, and depleted in less soluble species like CH4 and N2. Stage 2 condensation processes can therefore be monitored by ratios of more and less condensable species like CO2/N2. Condensation of vapor released by boiling geothermal fluids results in liquids with high concentrations of H2S and CO2 like is seen in geothermal system steam-heated waters. Condensation of a magmatic vapor into circulating meteoric water has been proposed, but not well demonstrated. We compare to our models the Cerro Prieto, Mexico gas analysis data set collected over twelve years time by USGS personnel. It was assumed for modeling that the Cerro Prieto geothermal fluids are circulating meteoritic fluids with N2/Ar ratios about 40 to which is added a magmatic vapor with N2/Ar ratio = 400. The Cerro Prieto analyses show a strong correlation between N2/Ar and CO2/N2 as predicted by calculation. Two dimensional image plots of well N2/Ar + CO2/N2 show a bull's-eye pattern on the geothermal field. Image plots of analyses collected over a year or less time show N2/Ar and CO2/N2 hot spots

  7. Dynamics of chromosomal aberrations, induction of apoptosis, BRCA2 degradation and sensitization to radiation by hyperthermia.

    Science.gov (United States)

    Bergs, Judith W J; Oei, Arlene L; Ten Cate, Rosemarie; Rodermond, Hans M; Stalpers, Lukas J; Barendsen, Gerrit W; Franken, Nicolaas A P

    2016-07-01

    Hyperthermia can transiently degrade BRCA2 and thereby inhibit the homologous recombination pathway. Induced DNA-double strand breaks (DSB) then have to be repaired via the error prone non-homologous end-joining pathway. In the present study, to investigate the role of hyperthermia in genotoxicity and radiosensitization, the induction of chromosomal aberrations was examined by premature chromosome condensation and fluorescence in situ hybridisation (PCC-FISH), and cell survival was determined by clonogenic assay shortly (0-1 h) and 24 h following exposure to hyperthermia in combination with ionizing radiation. Prior to exposure to 4 Gy γ-irradiation, confluent cultures of SW‑1573 (human lung carcinoma) and RKO (human colorectal carcinoma) cells were exposed to mild hyperthermia (1 h, 41˚C). At 1 h, the frequency of chromosomal translocations was higher following combined exposure than following exposure to irradiation alone. At 24 h, the number of translocations following combined exposure was lower than following exposure to irradiation only, and was also lower than at 1 h following combined exposure. These dynamics in translocation frequency can be explained by the hyperthermia-induced transient reduction of BRCA2 observed in both cell lines. In both cell lines exposed to radiation only, potentially lethal damage repair (PLDR) correlated with a decreased number of chromosomal fragments at 24 h compared to 1 h. With combined exposure, PLDR did not correlate with a decrease in fragments, as in the RKO cells at 24 h following combined exposure, the frequency of fragments remained at the level found after 1 h of exposure and was also significantly higher than that found following exposure to radiation alone. This was not observed in the SW‑1573 cells. Cell survival experiments demonstrated that exposure to hyperthermia radiosensitized the RKO cells, but not the SW‑1573 cells. This radiosensitization was at least partly due to the induction

  8. Condensation in Saturn's Stratospheric Haze Layers

    Science.gov (United States)

    Barth, Erika L.; Moses, Julianne I.

    2016-10-01

    Haze particles in Saturn's stratosphere can be seen in the visible limb images of Cassini's Imaging Science Subsystem (ISS). These hazes are likely a mix of particles, including solid organics formed as a result of methane photolysis and electron deposition, as well as the condensation of water and hydrocarbon ices. We have examined data from both Cassini and Voyager to study the detailed vertical structure of absorbing/scattering particulates in Saturn's stratosphere and developed a Saturn version of the Community Aerosol and Radiation Model for Atmospheres (CARMA), adding a large database of hydrocarbons that are observed or expected to be present in Saturn's atmosphere.Our modeling indicates that water ice condenses independently of the hydrocarbons to form a thin layer above the 0.1 mbar pressure level. Between about 5 and 50 mbar, the hydrocarbons reach their condensation levels (in order of increasing pressure level): C6H6, C5H12, C4H2, C4H10, and C2H2. Because of the proximity of their condensation levels and due to the gravitational settling of the particles, the hydrocarbons are likely condensing on one another and forming a thicker layer of mixed composition. Interestingly, butane (C4H10) has a triple point around 135 K which is much lower than most of the other condensing species we've explored. Given an approximate condensation level of 10 mbar and the observed temperature changes at this pressure level following the December 2010 northern-hemisphere storm (stratospheric temperatures were elevated by as much as 50-70 K in a region near 40° N latitude.), melting and further nucleation of droplets could be occurring.A number of factors including temperature profile, vapor pressure equation, volatile abundance, nucleation critical saturation, and coagulation efficiency will affect the altitudes of the individual ice layers. We will present a summary of results following the nucleation and growth of compounds in order to quantify the likely size and

  9. Diffusion in condensed matter methods, materials, models

    CERN Document Server

    Kärger, Jörg

    2005-01-01

    Diffusion as the process of particle transport due to stochastic movement is a phenomenon of crucial relevance for a large variety of processes and materials. This comprehensive, handbook- style survey of diffusion in condensed matter gives detailed insight into diffusion as the process of particle transport due to stochastic movement. Leading experts in the field describe in 23 chapters the different aspects of diffusion, covering microscopic and macroscopic experimental techniques and exemplary results for various classes of solids, liquids and interfaces as well as several theoretical concepts and models. Students and scientists in physics, chemistry, materials science, and biology will benefit from this detailed compilation.

  10. Black Hole Bose Condensation

    Science.gov (United States)

    Vaz, Cenalo; Wijewardhana, L. C. R.

    2013-12-01

    General consensus on the nature of the degrees of freedom responsible for the black hole entropy remains elusive despite decades of effort dedicated to the problem. Different approaches to quantum gravity disagree in their description of the microstates and, more significantly, in the statistics used to count them. In some approaches (string theory, AdS/CFT) the elementary degrees of freedom are indistinguishable, whereas they must be treated as distinguishable in other approaches to quantum gravity (eg., LQG) in order to recover the Bekenstein-Hawking area-entropy law. However, different statistics will imply different behaviors of the black hole outside the thermodynamic limit. We illustrate this point by quantizing the Bañados-Teitelboim-Zanelli (BTZ) black hole, for which we argue that Bose condensation will occur leading to a "cold", stable remnant.

  11. Condensate filtering device

    International Nuclear Information System (INIS)

    In a condensate filtering device of a nuclear power plant, a water collecting pipe is disposed over the entire length, an end of a hollow thread is in communication with the water collecting pipe and secured. If the length of the water collecting pipe is extended, a filtering device of an optional length can be obtained irrespective of the length of the hollow thread. Therefore, since there is no need to connect units upon constituting a module, flow of cleaning gases is not restricted at connection portions. Accordingly, even if the volume of the device is increased by the extension of the module, the working life of the module is not degraded. (T.M.)

  12. Microgravity condensing heat exchanger

    Science.gov (United States)

    Thomas, Christopher M. (Inventor); Ma, Yonghui (Inventor); North, Andrew (Inventor); Weislogel, Mark M. (Inventor)

    2011-01-01

    A heat exchanger having a plurality of heat exchanging aluminum fins with hydrophilic condensing surfaces which are stacked and clamped between two cold plates. The cold plates are aligned radially along a plane extending through the axis of a cylindrical duct and hold the stacked and clamped portions of the heat exchanging fins along the axis of the cylindrical duct. The fins extend outwardly from the clamped portions along approximately radial planes. The spacing between fins is symmetric about the cold plates, and are somewhat more closely spaced as the angle they make with the cold plates approaches 90.degree.. Passageways extend through the fins between vertex spaces which provide capillary storage and communicate with passageways formed in the stacked and clamped portions of the fins, which communicate with water drains connected to a pump externally to the duct. Water with no entrained air is drawn from the capillary spaces.

  13. Superconductivity of the pion condensate

    Energy Technology Data Exchange (ETDEWEB)

    Anisimov, N.Y.; Voskresenskii, D.N.

    1979-10-01

    The pion condensate in nuclear matter with k/sub 0/not =0 in a magnetic field is investigated. It is found that the pion condensate is a Type II superconductor. A lamellar mixed state exists in the vicinity of H/sub c/. The critical field are estimated to be of the order 10/sup 16/--10/sup 18/ G.

  14. Chromosomal breakpoints characterization of two supernumerary ring chromosomes 20.

    Science.gov (United States)

    Guediche, N; Brisset, S; Benichou, J-J; Guérin, N; Mabboux, P; Maurin, M-L; Bas, C; Laroudie, M; Picone, O; Goldszmidt, D; Prévot, S; Labrune, P; Tachdjian, G

    2010-02-01

    The occurrence of an additional ring chromosome 20 is a rare chromosome abnormality, and no common phenotype has been yet described. We report on two new patients presenting with a supernumerary ring chromosome 20 both prenatally diagnosed. The first presented with intrauterine growth retardation and some craniofacial dysmorphism, and the second case had a normal phenotype except for obesity. Conventional cytogenetic studies showed for each patient a small supernumerary marker chromosome (SMC). Using fluorescence in situ hybridization, these SMCs corresponded to ring chromosomes 20 including a part of short and long arms of chromosome 20. Detailed molecular cytogenetic characterization showed different breakpoints (20p11.23 and 20q11.23 for Patient 1 and 20p11.21 and 20q11.21 for Patient 2) and sizes of the two ring chromosomes 20 (13.6 Mb for case 1 and 4.8 Mb for case 2). Review of the 13 case reports of an extra r(20) ascertained postnatally (8 cases) and prenatally (5 cases) showed varying degrees of phenotypic abnormalities. We document a detailed molecular cytogenetic chromosomal breakpoints characterization of two cases of supernumerary ring chromosomes 20. These results emphasize the need to characterize precisely chromosomal breakpoints of supernumerary ring chromosomes 20 in order to establish genotype-phenotype correlation. This report may be helpful for prediction of natural history and outcome, particularly in prenatal diagnosis.

  15. Familial complex chromosomal rearrangement resulting in a recombinant chromosome.

    Science.gov (United States)

    Berend, Sue Ann; Bodamer, Olaf A F; Shapira, Stuart K; Shaffer, Lisa G; Bacino, Carlos A

    2002-05-15

    Familial complex chromosomal rearrangements (CCRs) are rare and tend to involve fewer breakpoints and fewer chromosomes than CCRs that are de novo in origin. We report on a CCR identified in a child with congenital heart disease and dysmorphic features. Initially, the child's karyotype was thought to involve a straightforward three-way translocation between chromosomes 3, 8, and 16. However, after analyzing the mother's chromosomes, the mother was found to have a more complex rearrangement that resulted in a recombinant chromosome in the child. The mother's karyotype included an inverted chromosome 2 and multiple translocations involving chromosomes 3, 5, 8, and 16. No evidence of deletion or duplication that could account for the clinical findings in the child was identified.

  16. PPOOLEX experiments on wall condensation

    Energy Technology Data Exchange (ETDEWEB)

    Laine, J.; Puustinen, M. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

    2009-08-15

    This report summarizes the results of the wall condensation experiments carried out in December 2008 and January 2009 with the scaled down PPOOLEX test facility designed and constructed at Lappeenranta University of Technology. Steam was blown into the dry well compartment and from there through a DN200 blowdown pipe to the condensation pool. Altogether five experiments, each consisting of several blows, were carried out. The main purpose of the experiment series was to study wall condensation phenomenon inside the dry well compartment while steam is discharged through it into the condensation pool and to produce comparison data for CFD calculations at VTT. The PPOOLEX test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. For the wall condensation experiments the test facility was equipped with a system for collecting and measuring the amount of condensate from four different wall segments of the dry well compartment. A thermo graphic camera was used in a couple of experiments for filming the outside surface of the dry well wall. The effect of the initial temperature level of the dry well structures and of the steam flow rate for the accumulation of condensate was studied. The initial temperature level of the dry well structures varied from 23 to 99 deg. C. The steam flow rate varied from 90 to 690 g/s and the temperature of incoming steam from 115 to 160 deg. C. During the initial phase of steam discharge the accumulation of condensate was strongly controlled by the temperature level of the dry well structures; the lower the initial temperature level was the more condensate was accumulated. As the dry well structural temperatures increased the condensation process slowed down. Most of the condensate usually accumulated during the first 200 seconds of the discharge. However, the condensation process never completely stopped because a small temperature difference remained between the dry well atmosphere and inner wall

  17. Statistical steady state in turbulent droplet condensation

    CERN Document Server

    Siewert, Christoph; Krstulovic, Giorgio

    2016-01-01

    Motivated by the early stages of clouds and other systems in which droplets grow and shrink in a turbulence-driven supersaturation field, we investigate the problem of turbulent condensation using direct numerical simulations. The turbulent fluctuations of the supersaturation field offer different conditions for the growth of droplets which evolve in time due to turbulent transport and mixing. Based on that, we propose a Lagrangian stochastic model for condensation and evaporation of small droplets in turbulent flows. It consists of a set of stochastic integro-differential equations for the joint evolution of the squared radius and the supersaturation along the droplet trajectories. The model has two parameters fixed by the total amount of water and the thermodynamic properties, as well as the Lagrangian integral timescale of the turbulent supersaturation. The model reproduces very well the droplet size distributions obtained from direct numerical simulations and their time evolution. A noticeable result is t...

  18. Off gas condenser performance modelling

    International Nuclear Information System (INIS)

    A suite of three programmes has been developed to model the ruthenium decontamination performance of a vitrification plant off-gas condenser. The stages of the model are: condensation of water vapour, NOx absorption in the condensate, RuO4 absorption in the condensate. Juxtaposition of these stages gives a package that may be run on an IBM-compatible desktop PC. Experimental work indicates that the criterion [HNO2] > 10 [RuO4] used to determine RuO4 destruction in solution is probably realistic under condenser conditions. Vapour pressures of RuO4 over aqueous solutions at 70o-90oC are slightly lower than the values given by extrapolating the ln Kp vs. T-1 relation derived from lower temperature data. (author)

  19. Review of steam jet condensation in a water pool

    International Nuclear Information System (INIS)

    In the advanced nuclear power plants including APR1400, the SDVS is adopted to increase the plant safety using the concept of feed-and-bleed operation. In the case of the TLOFW, the POSRV located at the top of the pressurizer is expected to open due to the pressurization of the reactor coolant system and discharges steam and/or water mixture into the water pool, where the mixture is condensed. During the condensation of the mixture, thermal-hydraulic loads such as pressure and temperature variations are induced to the pool structure. For the pool structure design, such thermal-hydraulic aspects should be considered. Understanding the phenomena of the submerged steam jet condensation in a water pool is helpful for system designers to design proper pool structure, sparger, and supports etc. This paper reviews and evaluates the steam jet condensation in a water pool on the physical phenomena of the steam condensation including condensation regime map, heat transfer coefficient, steam plume, steam jet condensation load, and steam jet induced flow

  20. Review of steam jet condensation in a water pool

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y. S.; Song, C. H.; Park, C. K.; Kang, H. S.; Jeon, H. G.; Yoon, Y. J. [KAERI, Taejon (Korea, Republic of)

    2002-10-01

    In the advanced nuclear power plants including APR1400, the SDVS is adopted to increase the plant safety using the concept of feed-and-bleed operation. In the case of the TLOFW, the POSRV located at the top of the pressurizer is expected to open due to the pressurization of the reactor coolant system and discharges steam and/or water mixture into the water pool, where the mixture is condensed. During the condensation of the mixture, thermal-hydraulic loads such as pressure and temperature variations are induced to the pool structure. For the pool structure design, such thermal-hydraulic aspects should be considered. Understanding the phenomena of the submerged steam jet condensation in a water pool is helpful for system designers to design proper pool structure, sparger, and supports etc. This paper reviews and evaluates the steam jet condensation in a water pool on the physical phenomena of the steam condensation including condensation regime map, heat transfer coefficient, steam plume, steam jet condensation load, and steam jet induced flow.

  1. Transient condensation tests on an emergency condensator - single tube

    International Nuclear Information System (INIS)

    The report presents experiments which were aimed at studying steam condensation in horizontal respectively slightly inclined pipes at high driving temperature differences of up to 200 K. Further specifics are the detailed investigation of the transient behaviour of a non-condensable gas using a novel measuring technique as well as the evaluation of the influence of the gas upon the condensation intensity. For this purpose in the experiment a rapid transient process was realized, which was initiated by suddenly connecting a heat exchanger pipe resting in a pool of cooling water with the steam dome of a pressure vessel. In the pipe, different initial conditions were adjusted by varying the initial pressure of the non-condensable gas (air). Experiments were carried out with atmospheric pressure, with increased air pressure, but also with an evacuated pipe. The new instrumentation consists in novel needle-shaped void probes, which allow the local phase detection combined with a fast temperature measurement. This makes it possible to study the redistribution of steam, condensate and non-condensable as a function of time with a high resolution. The obtained data offer the possibility to validate the models for the prediction of the transport and the effect of non-condensable gases in thermal hydraulic system codes under transient conditions. (orig.)

  2. Condensation of water vapor and carbon dioxide in the jet exhausts of rocket engines: 1. Heterogeneous condensation of combustion products

    Science.gov (United States)

    Platov, Yu. V.; Semenov, A. I.; Filippov, B. V.

    2014-01-01

    Condensation of water vapor and carbon dioxide in the jet exhausts of rocket engines during last stages of Proton, Molniya, and Start launchers operating in the upper atmospheric with different types of fuels is considered. Particle heating is taken into account with emission of latent heat of condensation and energy loss due to radiation and heat exchange with combustion products. Using the solution of the heat balance and condensed particle mass equations, the temporal change in the temperature and thickness of the condensate layer is obtained. Practically, no condensation of water vapor and carbon dioxide in the jet exhaust of a Start launcher occurs. In plumes of Proton and Molniya launchers, the condensation of water vapor and carbon dioxide can start at distances of 120-170 m and 450-650 m from the engine nozzle, respectively. In the course of condensation, the thickness of the "water" layer on particles can exceed 100 Å, and the thickness of carbon dioxide can exceed 60 Å.

  3. Film-wise and drop-wise condensation of steam on short inclined plates

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Bum Jin; Kim, Min Chan [Cheju National University, Jeju (Korea, Republic of); Ahmadinejad, Mehrdad [Johnson Matthey Blount' s Court, Reading (United Kingdom)

    2008-01-15

    Film-wise and drop-wise condensation experiments were carried out at atmospheric pressure varying the condensing plates, their inclinations and orientations (upward or downward facing), and the air concentrations. As expected, dropwise condensation showed much higher heat transfer rates than corresponding film-wise condensation in the pure steam cases. However, with the presence of air, both modes of condensation showed similar heat transfer rates due to the high thermal resistance of the air-rich layer. Both modes of condensation showed systematic decreases in heat transfer as the angle of the plate to the horizontal decreased and as the concentration of air increased. A noteworthy observation made during the tests on the plate orientation showed that condensation heat transfer rates on the upward facing plate were slightly higher than those beneath the downward facing plate in the pure steam cases but that the trends were reversed in the steam and air mixture cases

  4. Study of steady and unsteady wet steam condensing flows in a turbine stage

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To develop the numerical method for the steady and unsteady wet steam condensing flow in turbine stage. Methods An Eulerian/Eulerian numerical model is used to describe the spontaneous condensation flow in the steam turbine. For the steady condensing flow computations, the mixing plane model was used. For the unsteady condensing flow computations, the sliding mesh method was used to simulate the rotor-stator interactions. Results The numerical results showed the obvious differences between non-condensing and condensing flows. The results also showed the unsteadiness effect due to rotor-stator interactions had a deep influence on the formation and growth process of water droplets. Conclusion The numerical methods presented in this paper are valid for the condensing flow in the turbine stage.

  5. Integral Reactor Containment Condensation Model and Experimental Validation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qiao [Oregon State Univ., Corvallis, OR (United States); Corradini, Michael [Univ. of Wisconsin, Madison, WI (United States)

    2016-05-02

    ranging from 4 to 21 bar with three different static inventories of non-condensable gas. Condensation and heat transfer rates were evaluated employing several methods, notably from measured temperature gradients in the HTP as well as measured condensate formation rates. A detailed mass and energy accounting was used to assess the various measurement methods and to support simplifying assumptions required for the analysis. Condensation heat fluxes and heat transfer coefficients are calculated and presented as a function of pressure to satisfy the objectives of this investigation. The major conclusions for those tests are summarized below: (1) In the steam blow-down tests, the initial condensation heat transfer process involves the heating-up of the containment heat transfer plate. An inverse heat conduction model was developed to capture the rapid transient transfer characteristics, and the analysis method is applicable to SMR safety analysis. (2) The average condensation heat transfer coefficients for different pressure conditions and non-condensable gas mass fractions were obtained from the integral test facility, through the measurements of the heat conduction rate across the containment heat transfer plate, and from the water condensation rates measurement based on the total energy balance equation. 15 (3) The test results using the measured HTP wall temperatures are considerably lower than popular condensation models would predict mainly due to the side wall conduction effects in the existing MASLWR integral test facility. The data revealed the detailed heat transfer characteristics of the model containment, important to the SMR safety analysis and the validation of associated evaluation model. However this approach, unlike separate effect tests, cannot isolate the condensation heat transfer coefficient over the containment wall, and therefore is not suitable for the assessment of the condensation heat transfer coefficient against system pressure and noncondensable

  6. Generating periodic interference in Bose–Einstein condensates

    Science.gov (United States)

    Ji, Shen-Tong; Wang, Yuan-Sheng; Luo, Yue-E.; Liu, Xue-Shen

    2016-09-01

    The interference between two condensates with repulsive interaction is investigated numerically by solving the one-dimensional time-dependent Gross–Pitaevskii equation. The periodic interference pattern forms in two condensates, which are prepared in a double-well potential consisting of two truncated harmonic wells centered at different positions. Dark solitons are observed when two condensates overlap. Due to the existence of atom–atom interactions, atoms are transferred among the ground state and the excited states, which coincides with the condensate energy change. Project supported by the Doctoral Funds of Guizhou Normal College, China (Grant No. 2015BS006) and the National Natural Science Foundation of China (Grant Nos. 11271158 and 11174108).

  7. Simulating the in situ condensation process of solar prominences

    CERN Document Server

    Xia, Chun; Antolin, Patrick; Porth, Oliver

    2014-01-01

    Prominences in the solar corona are hundredfold cooler and denser than their surroundings, with a total mass of 1.e13 up to 1.e15 g. Here we report on the first comprehensive simulations of three-dimensional, thermally and gravitationally stratified magnetic flux ropes, where in situ condensation to a prominence happens due to radiative losses. After a gradual thermodynamic adjustment, we witness a phase where runaway cooling happens while counter-streaming shearing flows drain off mass along helical field lines. After this drainage, a prominence-like condensation resides in concave upward field regions, and this prominence retains its overall characteristics for more than two hours. While condensing, the prominence establishes a prominence-corona transition region, where magnetic field-aligned thermal conduction is operative during the runaway cooling. The prominence structure represents a force-balanced state in a helical flux rope. The simulated condensation demonstrates a right-bearing barb, as a remnant ...

  8. Construction of human chromosome 21-specific yeast artificial chromosomes.

    Science.gov (United States)

    McCormick, M K; Shero, J H; Cheung, M C; Kan, Y W; Hieter, P A; Antonarakis, S E

    1989-12-01

    Chromosome 21-specific yeast artificial chromosomes (YACs) have been constructed by a method that performs all steps in agarose, allowing size selection by pulsed-field gel electrophoresis and the use of nanogram to microgram quantities of DNA. The DNA sources used were hybrid cell line WAV-17, containing chromosome 21 as the only human chromosome and flow-sorted chromosome 21. The transformation efficiency of ligation products was similar to that obtained in aqueous transformations and yielded YACs with sizes ranging from 100 kilobases (kb) to greater than 1 megabase when polyamines were included in the transformation procedure. Twenty-five YACs containing human DNA have been obtained from a mouse-human hybrid, ranging in size from 200 to greater than 1000 kb, with an average size of 410 kb. Ten of these YACs were localized to subregions of chromosome 21 by hybridization of RNA probes (corresponding to the YAC ends recovered in Escherichia coli) to a panel of somatic cell hybrid DNA. Twenty-one human YACs, ranging in size from 100 to 500 kb, with an average size of 150 kb, were obtained from approximately equal to 50 ng of flow-sorted chromosome 21 DNA. Three were localized to subregions of chromosome 21. YACs will aid the construction of a physical map of human chromosome 21 and the study of disorders associated with chromosome 21 such as Alzheimer disease and Down syndrome.

  9. Condensation in Nanoporous Packed Beds.

    Science.gov (United States)

    Ally, Javed; Molla, Shahnawaz; Mostowfi, Farshid

    2016-05-10

    In materials with tiny, nanometer-scale pores, liquid condensation is shifted from the bulk saturation pressure observed at larger scales. This effect is called capillary condensation and can block pores, which has major consequences in hydrocarbon production, as well as in fuel cells, catalysis, and powder adhesion. In this study, high pressure nanofluidic condensation studies are performed using propane and carbon dioxide in a colloidal crystal packed bed. Direct visualization allows the extent of condensation to be observed, as well as inference of the pore geometry from Bragg diffraction. We show experimentally that capillary condensation depends on pore geometry and wettability because these factors determine the shape of the menisci that coalesce when pore filling occurs, contrary to the typical assumption that all pore structures can be modeled as cylindrical and perfectly wetting. We also observe capillary condensation at higher pressures than has been done previously, which is important because many applications involving this phenomenon occur well above atmospheric pressure, and there is little, if any, experimental validation of capillary condensation at such pressures, particularly with direct visualization. PMID:27115446

  10. Efficient, Long-Life Biocidal Condenser Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Environmental control systems for manned lunar and planetary bases will require condensing heat exchangers to control humidity in manned modules. Condensing...

  11. Efficient, Long-Life Biocidal Condenser Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Environmental control systems for manned lunar and planetary bases will require condensing heat exchangers to control humidity. Condensing surfaces must be...

  12. Metal vapor condensation under high pressure (mercury vapor to 500 psia). [Heat transfer coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, S.; Bonilla, C.F.

    1975-01-01

    Mercury vapor up to 500 psia was condensed outside a cylindrical tube in both horizontal and vertical positions. Results show consistently low heat transfer coefficients compared to Nusselt's theory. Two auxiliary mercury vapor condensers downstream of the boiler vent were used to control and safeguard the system. Constantan wires were spot welded on the surface inside the test condenser tube. The heat flux ranged from 20,000 to 45,000 Btu/h-ft/sup 2/ and the temperature differences between vapor and condensing wall from 6 to 50/sup 0/F. The condensation heat transfer coefficients, ranging from 850 to 3,500 Btu/h-/sup 0/F-ft/sup 2/, are only about 3 to 9 percent of those predicted by Nusselt's theory. Due to the positive pressure in the system for most test runs, the chance of any in-leakage of noncondensable gases into the boiler is extremely small. Since no substantial change of heat transfer rate resulted from wide variations in the heat load on the reflux condenser at some specific heat flux on the test condenser tube, the low heat transfer rate of mercury vapor condensation was not due to the presence of any non-condensable gas. The test data for high vapor pressure up to 500 psia reveal that the heat transfer coefficient is independent of the vapor pressure level. The condensation coefficients calculated based on kinetic theory are much smaller than unity and decreasewith vapor pressure. It is hypothesized that dimer content in the metal vapor phase might behave as non-condensable or semi-condensable gas and create a diffusional barrier at the vapor-liquid interface near the condensate film. This dimer vapor could be the main cause of interfacial resistance during metal vapor condensation process. 41 figures, 7 tables, 58 references. (DLC)

  13. Electric-field-enhanced condensation on superhydrophobic nanostructured surfaces.

    Science.gov (United States)

    Miljkovic, Nenad; Preston, Daniel J; Enright, Ryan; Wang, Evelyn N

    2013-12-23

    When condensed droplets coalesce on a superhydrophobic nanostructured surface, the resulting droplet can jump due to the conversion of excess surface energy into kinetic energy. This phenomenon has been shown to enhance condensation heat transfer by up to 30% compared to state-of-the-art dropwise condensing surfaces. However, after the droplets jump away from the surface, the existence of the vapor flow toward the condensing surface increases the drag on the jumping droplets, which can lead to complete droplet reversal and return to the surface. This effect limits the possible heat transfer enhancement because larger droplets form upon droplet return to the surface, which impedes heat transfer until they can be either removed by jumping again or finally shedding via gravity. By characterizing individual droplet trajectories during condensation on superhydrophobic nanostructured copper oxide (CuO) surfaces, we show that this vapor flow entrainment dominates droplet motion for droplets smaller than R ≈ 30 μm at moderate heat fluxes (q″ > 2 W/cm(2)). Subsequently, we demonstrate electric-field-enhanced condensation, whereby an externally applied electric field prevents jumping droplet return. This concept leverages our recent insight that these droplets gain a net positive charge due to charge separation of the electric double layer at the hydrophobic coating. As a result, with scalable superhydrophobic CuO surfaces, we experimentally demonstrated a 50% higher overall condensation heat transfer coefficient compared to that on a jumping-droplet surface with no applied field for low supersaturations (condensation heat transfer enhancement but also offers avenues for improving the performance of self-cleaning and anti-icing surfaces as well as thermal diodes.

  14. Organizing the bacterial chromosome for division

    Science.gov (United States)

    Broedersz, Chase

    2014-03-01

    The chromosome is highly organized in space in many bacteria, although the origin and function of this organization remain unclear. This organization is further complicated by the necessity for chromosome replication and segregation. Partitioning proteins of the ParABS system mediate chromosomal and plasmid segregation in a variety of bacteria. This segregation machinery includes a large ParB-DNA complex consisting of roughly 1000 ParB dimers, which localizes around one or a few centromere-like parS sites near the origin of replication. Despite the apparent simplicity of this segregation machinery as compared to eukaryotic segregations systems, puzzles remain: In particular, what is the nature of interactions among DNA-bound ParB proteins, and how do these determine the organizational and functional properties of the ParB-DNA partitioning complex? A crucial aspect of this question is whether ParB spreads along the DNA to form a filamentous protein-DNA complex with a 1D character, or rather assembles to form a 3D complex on the DNA. Furthermore, it remains unclear how the presence of only one or even a few parS sites can lead to robust formation and localization of such a large protein-DNA complex. We developed a simple model for interacting proteins on DNA, and found that a combination of 1D spreading bonds and a 3D bridging bond between ParB proteins constitutes the minimal model for condensation of a 3D ParB-DNA complex. These combined interactions provide an effective surface tension that prevents fragmentation of the ParB-DNA complex. Thus, ParB spreads to form multiple 1D domains on the DNA, connected in 3D by bridging interactions to assemble into a 3D ParB-DNA condensate. Importantly, this model accounts for recent experiments on ParB-induced gene-silencing and the effect of a DNA ``roadblock'' on ParB localization. Furthermore, our model provides a simple mechanism to explain how a single parS site is both necessary and sufficient for the formation and

  15. Bose condensation in (random traps

    Directory of Open Access Journals (Sweden)

    V.A. Zagrebnov

    2009-01-01

    Full Text Available We study a non-interacting (perfect Bose-gas in random external potentials (traps. It is shown that a generalized Bose-Einstein condensation in the random eigenstates manifests if and only if the same occurs in the one-particle kinetic-energy eigenstates, which corresponds to the generalized condensation of the free Bose-gas. Moreover, we prove that the amounts of both condensate densities are equal. This statement is relevant for justification of the Bogoliubov approximation} in the theory of disordered boson systems.

  16. First trimester ultrasound screening of chromosomal abnormalities

    Directory of Open Access Journals (Sweden)

    Trninić-Pjević Aleksandra

    2007-01-01

    Full Text Available Introduction: A retrocervical subcutaneous collection of fluid at 11-14 weeks of gestation, can be visualized by ultrasound as nuchal translucency (NT. Objective. To examine the distribution of fetal nuchal translucency in low risk population, to determine the detection rate of chromosomal abnormalities in the population of interest based on maternal age and NT measurement. Method. Screening for chromosomal defects, advocated by The Fetal Medicine Foundation (FMF, was performed in 1,341 pregnancies in the period January 2000 - April 2004. Initial risk for chromosomal defects (based on maternal and gestational age and corrected risk, after the NT measurement, were calculated. Complete data were collected from 1,048 patients. Results. Out of 1,048 pregnancies followed, 8 cases of Down’s syndrome were observed, 7 were detected antenatally and 6 out of 7 were detected due to screening that combines maternal age and NT measurement. According to our results, sensitivity of the screening for aneuploidies based on maternal age alone was 12.5% and false positive rate 13.1%, showing that screening based on NT measurement is of great importance. Screening by a combination of maternal age and NT, and selecting a screening-positive group for invasive testing enabled detection of 75% of fetuses with trisomy 21. Conclusion. In screening for chromosomal abnormalities, an approach which combines maternal age and NT is effective and increases the detection rate compared to the use of any single test. .

  17. Nondisjunction of chromosome 15: Origin and recombination

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, W.P.; Bernasconi, F.; Schinzel, A.A.; Mutirangura, A.; Ledbetter, D.H. (Baylor College of Medicine, Houston, TX (United States)); Langlois, S. (Univ. of Britisch Columbia, Vancouver (Canada)); Morris, M.A.; Malcolm, S.

    1993-09-01

    Thirty-two cases of uniparental disomy (UPD), ascertained from Prader-Willi syndrome patients (N=27) and Angelman syndrome patients (N-5), are used to investigate the pattern of recombination associated with nondisjunction of chromosome 15. In addition, the meiotic stage of nondisjunction is inferred by using markers mapping near the centromere. Two basic approaches to the analysis of recombination in specific pairwise intervals along the chromosome. This method shows a significant reduction in recombination for two of five intervals examined. Second, the observed frequency of each recombinant class (i.e., zero, one, two, three, or more observable crossovers) is compared with expected values. This is useful for testing whether the reduction in recombination can be attributed solely to a proportion of cases with no recombination at all (because of asynapsis), with the remaining groups showing normal recombination (or even excess recombination), or whether recombination is uniformly reduced. Analysis of maternal UPD(15) data shows a slight reduction in the multiple-recombinant classes, with a corresponding increase in both the zero- and one-recombinant classes over expected values. The majority, more than 82%, of the extra chromosomes in maternal UPD(15) cases are due to meiotic I nondisjunction events. In contrast, more paternal UPD(15) cases so far examined appear to have a postzygotic origin of the extra paternal chromosome. 33 refs., 1 fig., 7 tabs.

  18. M-Band Analysis of Chromosome Aberrations in Human Epithelial Cells Induced By Low- and High-Let Radiations

    Science.gov (United States)

    Hada, M.; Gersey, B.; Saganti, P. B.; Wilkins, R.; Gonda, S. R.; Cucinotta, F. A.; Wu, H.

    2007-01-01

    Energetic primary and secondary particles pose a health risk to astronauts in extended ISS and future Lunar and Mars missions. High-LET radiation is much more effective than low-LET radiation in the induction of various biological effects, including cell inactivation, genetic mutations, cataracts and cancer. Most of these biological endpoints are closely correlated to chromosomal damage, which can be utilized as a biomarker for radiation insult. In this study, human epithelial cells were exposed in vitro to gamma rays, 1 GeV/nucleon Fe ions and secondary neutrons whose spectrum is similar to that measured inside the Space Station. Chromosomes were condensed using a premature chromosome condensation technique and chromosome aberrations were analyzed with the multi-color banding (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of both interchromosomal (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Results of the study confirmed the observation of higher incidence of inversions for high-LET irradiation. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Half of the inversions observed in the low-LET irradiated samples were accompanied by other types of intrachromosome aberrations, but few inversions were accompanied by interchromosome aberrations. In contrast, Fe ions induced a significant fraction of inversions that involved complex rearrangements of both the inter- and intrachromosome exchanges.

  19. Dynamics of Spin-Orbit Coupled Bose-Einstein Condensates in a Random Potential.

    Science.gov (United States)

    Mardonov, Sh; Modugno, M; Sherman, E Ya

    2015-10-30

    Disorder plays a crucial role in spin dynamics in solids and condensed matter systems. We demonstrate that for a spin-orbit coupled Bose-Einstein condensate in a random potential two mechanisms of spin evolution that can be characterized as "precessional" and "anomalous" are at work simultaneously. The precessional mechanism, typical for solids, is due to the condensate displacement. The unconventional anomalous mechanism is due to the spin-dependent velocity producing the distribution of the condensate spin polarization. The condensate expansion is accompanied by a random displacement and fragmentation, where it becomes sparse, as clearly revealed in the spin dynamics. Thus, different stages of the evolution can be characterized by looking at the condensate spin. PMID:26565441

  20. Origin of uranium isotope variations in early solar nebula condensates

    OpenAIRE

    Tissot, François L. H.; Dauphas, Nicolas; Grossman, Lawrence

    2016-01-01

    High-temperature condensates found in meteorites display uranium isotopic variations (235U/238U), which complicate dating the solar system’s formation and whose origin remains mysterious. It is possible that these variations are due to the decay of the short-lived radionuclide 247Cm (t 1/2 = 15.6 My) into 235U, but they could also be due to uranium kinetic isotopic fractionation during condensation. We report uranium isotope measurements of meteoritic refractory inclusions that reveal excesse...

  1. Contrasting patterns of karyotype and sex chromosome evolution in Lepidoptera

    OpenAIRE

    Šíchová, Jindra

    2016-01-01

    It is known that chromosomal rearrangements play an important role in speciation by limiting gene flow within and between species. Furthermore, this effect may be enhanced by involvement of sex chromosomes that are known to undergo fast evolution compared to autosomes and play a special role in speciation due to their engagement in postzygotic reproductive isolation. The work presented in this study uses various molecular-genetic and cytogenetic techniques to describe karyotype and sex chromo...

  2. Experimental and theoretical study of reflux condensation

    Energy Technology Data Exchange (ETDEWEB)

    Bakke, Knut

    1997-12-31

    This thesis studies the separation of gas mixtures in a reflux condenser. also called a dephlegmator. Reflux condensation is separation of a gas mixture, in reflux flow with condensing liquid, under continuous heat removal. A numerical model of a dephlegmator for binary mixtures was developed. The model may readily be extended to multi-component mixtures, as the solution method is based on a matrix solver. Separation of a binary mixture in a reflux condenser test rig is demonstrated. The test facility contains a single-tube test section that was designed and built as part of the project. Test mixtures of propane and n-butane were used, and a total of 15 experiments are reported. Limited degree of separation was achieved due to limited heat transfer area and narrow boiling point range of the test mixture. The numerical model reproduces the experimental data within reasonable accuracy. Deviation between calculated and measured properties is less than 6% of the measured temperature and less than 5% of the measured flow rate. The model is based on mechanistic models of physical processes and is not calibrated or tuned to fit the experimental data. The numerical model is applied to a number of separation processes. These case studies show that the required heat transfer area increases rapidly with increments in top product composition (light component). Flooding limits the amount of reflux liquid. The dephlegmator is suitable for separation of feed mixtures that are rich in light components. The gliding temperature in the dephlegmation process enables utilization of top product as refrigerant, with subsequent energy saving as a result. 61 refs., 50 figs., 34 tabs.

  3. Quantum field theory and Bose Einstein condensation

    International Nuclear Information System (INIS)

    We study the phenomenon of Bose-Einstein condensation in cosmological and laboratory situations. To do this we examine the extreme temperature limits of a self-interacting O(2)-invariant scalar field theory with a non-zero charge density. The transition point has been well known for a long time in the case of an interactionless theory. However, due to a combination of technical problems imposed by having interactions and finite density, the transition in the interacting theory is not well understood. Here, in order to probe the Bose-Einstein condensation transition we perform a dimensional reduction of the 4D O(2)-invariant theory to give an effective theory in 3D. After dimensional reduction we use the 3D effective theory to calculate the two-loop effective potential which is used to examine the phase structure. This is a perturbative calculation and is still inappropriate for looking at the critical temperature. To find the critical temperature we use the non-perturbative linear delta expansion on the effective 3D theory. Tins is done in both the high temperature limit appropriate to cosmological applications and the low temperature limit appropriate to laboratory experiments with atomic gases. We study the Bose-Einstein condensation transition out of equilibrium. After a sudden quench which sends the system into the critical region, we look at how the condensate originates and grows. We study the equations of motion obtained from the one-loop effective action. It is found that the magnitude of the field expectation value grows at a slower rate at higher charge densities but that charge flows into the ground state at a faster rate at higher charge densities. In order to perform most of the analytic calculations, we show how dimensional regularization and Mellin summation can be elegantly combined to give an economical method for calculating high temperature Feynman diagrams. (author)

  4. Laser Filament Induced Water Condensation

    OpenAIRE

    Kasparian J.; Webe K.; Vogel A; Petit Y.; Lüder J.; Hao Z.Q.; Rohwetter P.; Petrarca M.; Stelmaszczyk K.; Henin S.; Wöste L.; Wolf J.-P.

    2013-01-01

    At relative humidities above 70%, femtosecond laser filaments generate aerosol particles and water droplets in the atmosphere. The water vapour condensation and droplet stabilization are assured by soluble species produced in the laser plasma.

  5. Nonequilibrium Thermodynamics of Wealth Condensation

    CERN Document Server

    Braun, D

    2006-01-01

    We analyze wealth condensation for a wide class of stochastic economy models on the basis of the economic analog of thermodynamic potentials, termed transfer potentials. The economy model is based on three common transfers modes of wealth: random transfer, profit proportional to wealth and motivation of poor agents to work harder. The economies never reach steady state. Wealth condensation is the result of stochastic tunneling through a metastable transfer potential. In accordance with reality, both wealth and income distribution transiently show Pareto tails for high income subjects. For metastable transfer potentials, exponential wealth condensation is a robust feature. For example with 10 % annual profit 1% of the population owns 50 % of the wealth after 50 years. The time to reach such a strong wealth condensation is a hyperbolic function of the annual profit rate.

  6. Hierarchical condensation near phase equilibrium

    Science.gov (United States)

    Olemskoi, A. I.; Yushchenko, O. V.; Borisyuk, V. N.; Zhilenko, T. I.; Kosminska, Yu. O.; Perekrestov, V. I.

    2012-06-01

    A novel mechanism of new phase formation is studied both experimentally and theoretically in the example of quasi-equilibrium stationary condensation in an ion-plasma sputterer. Copper condensates are obtained to demonstrate that a specific network structure is formed as a result of self-assembly in the course of deposition. The fractal pattern related is inherent in the phenomena of diffusion limited aggregation. Condensate nuclei are shown to form statistical ensemble of hierarchically subordinated objects distributed in ultrametric space. The Langevin equation and the Fokker-Planck equation related are found to describe stationary distribution of thermodynamic potential variations at condensation. Time dependence of the formation probability of branching structures is found to clarify the experimental situation.

  7. Nuclear fusion inside condense matters

    Institute of Scientific and Technical Information of China (English)

    HE Jing-tang

    2007-01-01

    This article describes in detail the nuclear fusion inside condense matters--the Fleischmann-Pons effect, the reproducibility of cold fusions, self-consistentcy of cold fusions and the possible applications.

  8. Zeolite Catalyzed Aldol Condensation Reactions

    Directory of Open Access Journals (Sweden)

    Adedayo I. Inegbenebor

    2015-03-01

    Full Text Available The review is based on the description of zeolite structure, uses, synthesis, and catalytic aldol reaction in aldol condensation. An internal aldolcondensation reaction has been achieved over ZSM-5 zeolite with high silica-alumina ratio at 350oC. It therefore follows that zeolite canfunction as a catalyst in aldol type condensation reactions and that weak acid sites as well as a small number of active sites favor the aldolcondensation reaction of carbonyl compounds. However, the mixed condensation product was found to be favored at temperatures above 300oCand the self-condensation of ethanal to crotonaldehyde was favored at temperatures below 300oC. It has also been suggested that both Brønstedand Lewis acids are involved in aldol reactions with Lewis acid sites the most probable catalytic sites. The zeolite group of minerals has founduse in many chemical and allied industries.

  9. Solar engineering - a condensed course

    Energy Technology Data Exchange (ETDEWEB)

    Broman, Lars

    2011-11-15

    The document represents the material covered in a condensed two-week course focusing on the most important thermal and PV solar energy engineering topics, while also providing some theoretical background.

  10. Condensed Matter Nuclear Science

    Science.gov (United States)

    Biberian, Jean-Paul

    2006-02-01

    1. General. A tribute to gene Mallove - the "Genie" reactor / K. Wallace and R. Stringham. An update of LENR for ICCF-11 (short course, 10/31/04) / E. Storms. New physical effects in metal deuterides / P. L. Hagelstein ... [et al.]. Reproducibility, controllability, and optimization of LENR experiments / D. J. Nagel -- 2. Experiments. Electrochemistry. Evidence of electromagnetic radiation from Ni-H systems / S. Focardi ... [et al.]. Superwave reality / I. Dardik. Excess heat in electrolysis experiments at energetics technologies / I. Dardik ... [et al.]. "Excess heat" during electrolysis in platinum/K[symbol]CO[symbol]/nickel light water system / J. Tian ... [et al.]. Innovative procedure for the, in situ, measurement of the resistive thermal coefficient of H(D)/Pd during electrolysis; cross-comparison of new elements detected in the Th-Hg-Pd-D(H) electrolytic cells / F. Celani ... [et al.]. Emergence of a high-temperature superconductivity in hydrogen cycled Pd compounds as an evidence for superstoihiometric H/D sites / A. Lipson ... [et al.]. Plasma electrolysis. Calorimetry of energy-efficient glow discharge - apparatus design and calibration / T. B. Benson and T. O. Passell. Generation of heat and products during plasma electrolysis / T. Mizuno ... [et al.]. Glow discharge. Excess heat production in Pd/D during periodic pulse discharge current in various conditions / A. B. Karabut. Beam experiments. Accelerator experiments and theoretical models for the electron screening effect in metallic environments / A. Huke, K. Czerski, and P. Heide. Evidence for a target-material dependence of the neutron-proton branching ratio in d+d reactions for deuteron energies below 20keV / A. Huke ... [et al.]. Experiments on condensed matter nuclear events in Kobe University / T. Minari ... [et al.]. Electron screening constraints for the cold fusion / K. Czerski, P. Heide, and A. Huke. Cavitation. Low mass 1.6 MHz sonofusion reactor / R. Stringham. Particle detection. Research

  11. Theoretical investigation of water vapour condensation in presence of noncondensable gases

    OpenAIRE

    Karkoszka, Krzysztof

    2005-01-01

    Steam condensation phenomenon plays an important role in many industrial applications. Especially in energy sector this process requires deep understanding. When noncondensable gases are taken into consideration description of the entire phenomenon becomes more complicated. If the surface condensation is taken into consideration this additional species accumulates and creates noncondensable layer near the surface on water vapour condenses. Due to this effect heat and mass transfer rates from ...

  12. Reduced Effective Model for Condensation in Slender Tubes with Rotational Symmetry, Obtained by Generalized Dimensional Analysis

    OpenAIRE

    Dziubek, Andrea

    2011-01-01

    Experimental results for condensation in compact heat exchangers show that the heat transfer due to condensation is significantly better compared to classical heat exchangers, especially when using R134a instead of water as the refrigerant. This suggests that surface tension plays a role. Using generalized dimensional analysis we derive reduced model equations and jump conditions for condensation in a vertical tube with cylindrical cross section. Based on this model we derive a single ordinar...

  13. Zeolite Catalyzed Aldol Condensation Reactions

    OpenAIRE

    Adedayo I. Inegbenebor; Raphael C. Mordi; Oluwakayode M. Ogunwole

    2015-01-01

    The review is based on the description of zeolite structure, uses, synthesis, and catalytic aldol reaction in aldol condensation. An internal aldolcondensation reaction has been achieved over ZSM-5 zeolite with high silica-alumina ratio at 350oC. It therefore follows that zeolite canfunction as a catalyst in aldol type condensation reactions and that weak acid sites as well as a small number of active sites favor the aldolcondensation reaction of carbonyl compounds. However, the mixed condens...

  14. DNA condensation in two dimensions

    OpenAIRE

    Koltover, Ilya; Wagner, Kathrin; Safinya, Cyrus R.

    2000-01-01

    We have found that divalent electrolyte counterions common in biological cells (Ca2+, Mg2+, and Mn2+ ) can condense anionic DNA molecules confined to two-dimensional cationic surfaces. DNA-condensing agents in vivo include cationic histones and polyamines spermidine and spermine with sufficiently high valence (Z) 3 or larger. In vitro studies show that electrostatic forces between DNA chains in bulk aqueous solution containing divalent counterions remain purely ...

  15. Intraspecific chromosome variability

    Directory of Open Access Journals (Sweden)

    N Dubinin

    2010-12-01

    Full Text Available (Editorial preface. The publication is presented in order to remind us of one of dramatic pages of the history of genetics. It re-opens for the contemporary reader a comprehensive work marking the priority change from plant cytogenetics to animal cytogenetics led by wide population studies which were conducted on Drosophila polytene chromosomes. The year of the publication (1937 became the point of irretrievable branching between the directions of Old World and New World genetics connected with the problems of chromosome variability and its significance for the evolution of the species. The famous book of T. Dobzhansky (1937 was published by Columbia University in the US under the title “Genetics and the origin of species”, and in the shadow of this American ‘skybuilding’ all other works grew dim. It is remarkable that both Dobzhansky and Dubinin come to similar conclusions about the role of chromosomes in speciation. This is not surprising given that they both might be considered as representatives of the Russian genetic school, by their birth and education. Interestingly, Dobzhansky had never referred to the full paper of Dubinin et al. (1937, though a previous short communication in Nature (1936 was included together with all former papers on the related subject. In full, the volume of the original publication printed in the Biological Journal in Moscow comprised 47 pages, in that number 41 pages of the Russian text accompanied by 16 Figs, a table and reference list, and, above all, 6 pages of the English summary. This final part in English is now reproduced in the authors’ version with the only addition being the reference list in the originally printed form.

  16. Chromosome assortment in Saccharum.

    Science.gov (United States)

    Al-Janabi, S M; Honeycutt, R J; Sobral, B W

    1994-12-01

    Recent work has revealed random chromosome pairing and assortment in Saccharum spontaneum L., the most widely distributed, and morphologically and cytologically variable of the species of Saccharum. This conclusion was based on the analysis of a segregating population from across between S. spontaneum 'SES 208' and a spontaneously-doubled haploid of itself, derived from anther culture. To determine whether polysomic inheritance is common in Saccharum and whether it is observed in a typical biparental cross, we studied chromosome pairing and assortment in 44 progeny of a cross between euploid, meiotically regular, 2n=80 forms of Saccharum officinarum 'LA Purple' and Saccharum robustum ' Mol 5829'. Papuan 2n=80 forms of S. robustum have been suggested as the immediate progenitor species for cultivated sugarcane (S. officinarum). A total of 738 loci in LA Purple and 720 loci in Mol 5829 were amplified and typed in the progeny by arbitrarily primed PCR using 45 primers. Fifty and 33 single-dose polymorphisms were identified in the S. officinarum and S. robustum genomes, respectively (χ 2 at 98%). Linkage analysis of single-dose polymorphisms in both genomes revealed linkages in repulsion and coupling phases. In the S. officinarum genome, a map hypothesis gave 7 linkage groups with 17 linked and 33 unlinked markers. Four of 13 pairwise linkages were in repulsion phase and 9 were in coupling phase. In the S. robustum genome, a map hypothesis gave 5 linkage groups, defined by 12 markers, with 21 markers unlinked, and 2 of 9 pairwise linkages were in repulsion phase. Therefore, complete polysomic inheritance was not observed in either species, suggesting that chromosomal behavior is different from that observed by linkage analysis of over 500 markers in the S. spontaneum map. Implications of this finding for evolution and breeding are discussed.

  17. Exhaled Breath Condensate for Proteomic Biomarker Discovery

    Directory of Open Access Journals (Sweden)

    Sean W. Harshman

    2014-07-01

    Full Text Available Exhaled breath condensate (EBC has been established as a potential source of respiratory biomarkers. Compared to the numerous small molecules identified, the protein content of EBC has remained relatively unstudied due to the methodological and technical difficulties surrounding EBC analysis. In this review, we discuss the proteins identified in EBC, by mass spectrometry, focusing on the significance of those proteins identified. We will also review the limitations surrounding mass spectral EBC protein analysis emphasizing recommendations to enhance EBC protein identifications by mass spectrometry. Finally, we will provide insight into the future directions of the EBC proteomics field.

  18. Condenser Optimization in Steam Power Plant

    Institute of Scientific and Technical Information of China (English)

    Sukru Bekdemir; Recep Ozturk; Zehra Yumurtac

    2003-01-01

    In this paper the effects of the condenser design parameters (such as turbine inlet condition, turbine power and condenser pressure) on heat transfer area, cooling water flow-rate, condenser cost and specific energy generation cost are studied for surface type condenser.The results are given in the text and also shown as diagrams.

  19. Sulphur condensation influence in Claus catalyst performance.

    Science.gov (United States)

    Mora, R L

    2000-12-01

    The Claus process is an efficient way of removing H(2)S from acid gas streams and this is widely practised in industries such as natural gas processing, oil refining and metal smelting. Increasingly strict pollution control regulations require maximum sulphur recovery from the Claus unit in order to minimise sulphur-containing effluent. The most widely used Claus catalyst in sulphur recovery units is non-promoted spherical activated alumina. Properties associated with optimum non-promoted Claus catalyst performance include high surface area, appropriate pore size distribution and enhanced physical properties. The objective of this paper is to outline a procedure in order to estimate Claus catalyst effectiveness after pore plugging due to sulphur condensation. Catalyst deactivation due to pore plugging by sulphur is modelled employing a Bethe lattice and its corresponding performance is described by means of a modified effectiveness factor. Model results show an improvement in the modified effectiveness factor due to modifications in catalyst porous structure.

  20. Rapid Drop Dynamics During Superhydrophobic Condensation

    Science.gov (United States)

    Zhang, Xiaodong; Boreyko, Jonathan; Chen, Chuan-Hua

    2008-11-01

    Rapid drop motion is observed on superhydrophobic surfaces during condensation; condensate drops with diameter of order 10 μm can move at above 100G and 0.1 m/s. When water vapor condenses on a horizontal superhydrophobic surface, condensate drops move in a seemingly random direction. The observed motion is attributed to the energy released through coalescence of neighboring condensate drops. A scaling analysis captured the initial acceleration and terminal velocity. Our work is a step forward in understanding the dynamics of superhydrophobic condensation occurring in both natural water-repellant plants and engineered dropwise condensers.

  1. Chromosome aberrations in ataxia telangiectasia cells exposed to heavy ions

    Science.gov (United States)

    Kawata, T.; Cucinotta, F.; George, K.; Wu, H.; Shigematsu, N.; Furusawa, Y.; Uno, T.; Isobe, K.; Ito, H.

    Understanding of biological effects of heavy ions is important to assess healt h risk in space. One of the most important issues may be to take into account individual susceptibility. Ataxia telangiectasia (A-T) cells are known to exhibit abnormal responses to radiations but the mechanism of hyper radiosensitivity of A-T still remains unknown. We report chromosome aberrations in normal human fibroblasts and AT fibroblasts exposed to low- and high-LET radiations. A chemical-induced premature chromosome condensation (PCC) technique combined with chromosome- painting technique was applied to score chromosome aberrations in G2/M-phase cells. Following gamma irradiation, GM02052 cells were approximately 5 times more sensitive to g-rays than AG1522 cells. GM02052 cells had a much higher frequency of deletions and misrejoining than AG1522 cells. When the frequency of complex type aberrations was compared, GM02052 cells showed more than 10 times higher frequency than AG1522 cells. The results will be compared with those obtained from high-LET irradiations.

  2. An investigation of direct condensation of steam jet in subcooled water

    International Nuclear Information System (INIS)

    The direct contact condensation phenomenon, which occurs when steam is injected into the subcooled water, has been experimentally investigated. Two plume shapes in the stable condensation regime are found to be conical and ellipsoidal shapes depending on the steam mass flux and the liquid subcooling. Divergent plumes, however, are found when the subcooling is relatively small. The measured expansion ratio of the maximum plume diameter to the injector inner diameter ranges from 1.0 to 2.3. By means of fitting a large amount of measured data, an empirical correlation is obtained to predict the steam plume length as a function of a dimensionless steam mass flux and a driving potential for the condensation process. The average heat transfer coefficient of direct contact condensation has been found to be in the range 1.0∼3.5 MW/m2 .deg. C. Present results show that the magnitude of the average condensation heat transfer coefficient depends mainly on the steam mass flux. By using dynamic pressure measurements and visual observations, six regimes of direct contact condensation have been identified on a condensation regime map, which are chugging, transition region from chugging to condensation oscillation, condensation oscillation, bubbling condensation oscillation, stable condensation, and interfacial oscillation condensation. The regime boundaries are quite clearly distinguishable except the boundaries of bubbling condensation oscillation and interfacial oscillation condensation. The measured heat transfer coefficients are compared with the several interfacial transport models, that is, the interfacial transport due to the turbulent intensity, the surface renewal, and the shear stress. The predicted value of the overall heat transfer coefficient by the one is reasonable with the experimental result. The others overestimate the experiment but within the same order of magnitude

  3. X chromosome inactivation: Activation of Silencing

    NARCIS (Netherlands)

    I.H. Jonkers (Iris)

    2009-01-01

    textabstractX chromosome inactivation is a process that ensures equal expression of the X chromosomes between males, which have one X and one Y chromosome, and females, which have two X chromosomes, in mammals. Females initiate inactivation of one of their two X chromosomes early during embryogenesi

  4. Chromosome Connections: Compelling Clues to Common Ancestry

    Science.gov (United States)

    Flammer, Larry

    2013-01-01

    Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

  5. X-chromosome workshop.

    Science.gov (United States)

    Paterson, A D

    1998-01-01

    Researchers presented results of ongoing research to the X-chromosome workshop of the Fifth World Congress on Psychiatric Genetics, covering a wide range of disorders: X-linked infantile spasms; a complex phenotype associated with deletions of Xp11; male homosexuality; degree of handedness; bipolar affective disorder; schizophrenia; childhood onset psychosis; and autism. This report summarizes the presentations, as well as reviewing previous studies. The focus of this report is on linkage findings for schizophrenia and bipolar disorder from a number of groups. For schizophrenia, low positive lod scores were obtained for markers DXS991 and DXS993 from two studies, although the sharing of alleles was greatest from brother-brother pairs in one study, and sister-sister in the other. Data from the Irish schizophrenia study was also submitted, with no strong evidence for linkage on the X chromosome. For bipolar disease, following the report of a Finnish family linked to Xq24-q27, the Columbia group reported some positive results for this region from 57 families, however, another group found no evidence for linkage to this region. Of interest, is the clustering of low positive linkage results that point to regions for possible further study. PMID:9686435

  6. Restriction enzyme buffers and 5-azacytidine induce loss of protein and banding in plant metaphase chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Olszewska, M.J.; Gernand, D.; Luchniak, P.; Sakowicz, T. [Lodz Univ. (Poland)

    1995-12-31

    The incubation of root meristem of `Vicia faba` L. with 5-azacytidine for 72 h (5 cell cycles) resulted in shorter DNA fragments after digestion with a restriction enzyme Sau3A. under the same condition `in situ` digestion of metaphase chromosomes with Sau3A revealed a stronger banding (C-banding-like) pattern in 5-azacytidine-treated chromosomes than in the control. This difference could hardly be attributed to the euchromatin demethylation as 5-azacytidine caused a loss of chromosomal proteins; similar effect was found as a result of incubation with some restriction endonuclease buffers which did not diminish the labelling with {sup 3}H-thymidine. After 5-azacytidine administration the entrance of cells into mitosis was delayed, the metaphase chromosomes were under condensed and the pattern of DNA replication remained unchanged. (author). 27 refs, 4 figs, 2 tabs.

  7. Restriction enzyme buffers and 5-azacytidine induce loss of protein and banding in plant metaphase chromosomes

    International Nuclear Information System (INIS)

    The incubation of root meristem of 'Vicia faba' L. with 5-azacytidine for 72 h (5 cell cycles) resulted in shorter DNA fragments after digestion with a restriction enzyme Sau3A. under the same condition 'in situ' digestion of metaphase chromosomes with Sau3A revealed a stronger banding (C-banding-like) pattern in 5-azacytidine-treated chromosomes than in the control. This difference could hardly be attributed to the euchromatin demethylation as 5-azacytidine caused a loss of chromosomal proteins; similar effect was found as a result of incubation with some restriction endonuclease buffers which did not diminish the labelling with 3H-thymidine. After 5-azacytidine administration the entrance of cells into mitosis was delayed, the metaphase chromosomes were under condensed and the pattern of DNA replication remained unchanged. (author). 27 refs, 4 figs, 2 tabs

  8. Experimental and numerical investigations on the air–steam mixture bubble condensation characteristics in stagnant cool water

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Xiao-hang; Tian, Mao-cheng, E-mail: tianmc65@sdu.edu.cn; Zhang, Guan-min; Leng, Xue-li

    2015-04-15

    Highlights: • Air–steam mixture bubble condensation behavior is studied by visual experiment. • VOF and species models are coupled to simulated mixture bubble condensation. • Condensation is model as source terms based on correlation from experiment. • Simulation results agree well with experimental results. • Steam concentration distribution in bubble is analyzed using numerical method. - Abstract: In this study, condensation of air–steam mixture bubble with mass fraction of steam above 0.5 was investigated first by a visual experiment at atmosphere. Then a 3-D numerical model based on volume of fluid (VOF) model and species model was developed to simulate the bubble condensation. In order to model steam condensation, mass and energy transfer between phases were modeled as source terms of conservation equations, using a correlation obtained from the experiment to predict the condensation heat transfer coefficient (HTC). After validation of the numerical model with the experimental results, influences of steam fraction and diameter of bubble on condensation characteristics are studied numerically. Moreover, steam concentration distribution in bubble was also analyzed along the time series of bubble condensation process. It was found that condensation HTC decreases with the increase of bubble diameter. With increase of steam fraction in bubble, the bubble volume shrinks more quickly due to the increased condensation rate, and the bubble accelerates more quickly reaching a higher terminal velocity. Aggregation of non-condensable air inside the bubble near the gas and water interface deteriorates the condensation heat and mass transfer.

  9. Unconventional Bose-Einstein Condensations from Spin-Orbit Coupling

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xiang-Fa; WU Cong-Jun; Ian Mondragon-Shem

    2011-01-01

    According to the "no-node" theorem, the many-body ground state wavefunctions of conventional Bose-Einstein condensations (BEC) are positive-definite, thus time-reversal symmetry cannot be spontaneously broken. We find that multi-component bosons with spin-orbit coupling provide an unconventional type of BECs beyond this paradigm. We focus on a subtle case ofisotropic Rashba spin-orbit coupling and the spin-independent interaction. In the limit of the weak confining potential, the condensate wavefunctions are frustrated at the Hartree-Fock level due to the degeneracy of the Rashba ring. Quantum zero-point energy selects the spin-spiral type condensate through the "order-from-disorder" mechanism. In a strong harmonic confining trap, the condensate spontaneously generates a half-quantum vortex combined with the skyrmion type of spin texture. In both cases, time-reversal symmetry is spontaneously broken. These phenomena can be realized in both cold atom systems with artificial spin-orbit couplings generated from atom-laser interactions and exciton condensates in semi-conductor systems.%@@ According to the"no-node"theorem,the many-body ground state wavefunctions of conventional Bose-Einstein condensations(BEC)are positive-definite,thus time-reversal symmetry cannot be spontaneously broken.We find that multi-component bosons with spin-orbit coupling provide an unconventional type of BECs beyond this paradigm.We focus on a subtle case of isotropic Rashba spin-orbit coupling and the spin-independent interaction.In the limit of the weak confining potential,the condensate wavefunctions are frustrated at the Hartree-Fork level due to the degeneracy of the Rashba ring.Quantum zero-point energy selects the spin-spiral type condensate through the"order-from-disorder"mechanism.In a strong harmonic confining trap,the condensate spontaneously generates a half-quantum vortex combined with the skyrmion type of spin texture.In both cases,time-reversal symmetry is spontaneously broken

  10. The Barley Chromosome 5 Linkage Map

    DEFF Research Database (Denmark)

    Jensen, J.; Jørgensen, Jørgen Helms

    1975-01-01

    The literature is surveyed for data on recombination between loci on chromosome 5 of barley; 13 loci fall into the category “mapped” loci, more than 20 into the category “associated” loci and nine into the category “loci once suggested to be on chromosome 5”. A procedure was developed...... for estimating a linkage map; it involves (1) transformation by the Kosambi mapping function of the available recombination percentages to additive map distances, (2) calculations of a set of map distances from the transformed recombination percentages by a maximum likelihood method in which all the available...... data are utilized jointly, and (3) omission of inconsistent data and determination of the most likely order of the loci. This procedure was applied to the 42 recombination percentages available for the 13 “mapped” loci. Due to inconsistencies 14 of the recombination percentages and, therefore, two...

  11. Chemical cleaning of the condenser tubes of Baersebaeck 2 - Experiences

    International Nuclear Information System (INIS)

    During the summer of 1980 the condenser tubes of Barsebaeck 2 were acid cleaned due to the following reasons: 1) significant heat transfer losses 2) possible passivation of attacks filled with corrosion products 3) encouraging experiences from acid cleaning of Danish units 4) less encouraging experiences from mechanical cleaning. Prior to the acid cleaning some laboratory experiments were performed to investigate the effect of pH-value and temperature on the time required for cleaning. In spite of practical problems including loss of acid and cavitating pumps the acid cleaning was performed in less than 24 hours/condenser section. The result of the acid cleaning was better than the result of mechanical methods employed earlier. There was a significant increase in heat transfer efficiency. In two of the condenser sections the tubes were completely free of corrosion products after acid cleaning and cleaning with the Taprogge system. In the two remaining condenser sections some corrosion products were observed in a few deep attacks. This is due to a higher pH-value suring the cleaning of these two sections than during the cleaning of the two first sections. There were no indications of any acid leaking to the steam side of the condenser. (Author)

  12. The oil margins of the Karadag gas condensate deposit

    Energy Technology Data Exchange (ETDEWEB)

    Melik-Pashayev, V.S.; Azhotkin, G.I.; Zhabrev, I.P.

    1983-01-01

    The results are reported of a geological and oil field analysis of the actual data from many years of development based on the subject of the behavior of the oil margins of the Karadag gas condensate and oil deposit. The conclusion about the absence of movement of the mapped stratum waters in the deposit and the oil margins into the gas condensate cap is justified. This occurs despite the fact that the current stratum pressures in the gas condensate cap have fallen further than in the oil margin. The opinion is expressed that such behavior of the oil margin is caused by the blockage of the pore channels as a result of resin and asphaltenes falling into the solid phase at the oil and condensate contact and due to the reduction in the phase penetrability for the oil due to the manifestation of a second gaseous phase with degasification of the oil margins. It is stressed that the noted behavior of the oil margin of the Karadag deposit is not necessarily repeated at other gas condensate and oil deposits, but the possibility of such behavior should be kept in mind.

  13. Noisy dynamics of a vortex in a partially Bose-Einstein condensed gas

    International Nuclear Information System (INIS)

    We study the dynamics of a straight vortex line in a partially Bose-Einstein condensed atomic gas. Using a variational approach to the stochastic field equation that describes the dynamics of the condensate at nonzero temperature, we derive the stochastic equations of motion for the position of the vortex core. Using these results, we calculate the time it takes the vortex to spiral out of the condensate. Due to the fact that we include thermal fluctuations in our description, this lifetime of the vortex is finite even if its initial position is in the center of the condensate

  14. Scrutinizing the pion condensed phase

    CERN Document Server

    Carignano, Stefano; Mammarella, Andrea; Mannarelli, Massimo; Pagliaroli, Giulia

    2016-01-01

    When the isospin chemical potential exceeds the pion mass, charged pions condense in the zero-momentum state forming a superfluid. Chiral perturbation theory provides a very powerful tool for studying this phase. However, the formalism that is usually employed in this context does not clarify various aspects of the condensation mechanism and makes the identification of the soft modes problematic. We re-examine the pion condensed phase using different approaches within the chiral perturbation theory framework. As a first step, we perform a low-density expansion of the chiral Lagrangian valid in the normal phase and close to the onset of the Bose-Einstein condensation. We obtain an effective theory that can be mapped to a Gross-Pitaevskii Lagrangian in which, remarkably, all the coefficients depend on the isospin chemical potential. The low-density expansion becomes unreliable deep in the pion condensed phase. For this reason, we develop an alternative field expansion deriving a low-energy Lagrangian analog to ...

  15. Causes of oncogenic chromosomal translocation

    OpenAIRE

    Aplan, Peter D.

    2005-01-01

    Non-random chromosomal translocations are frequently associated with a variety of cancers, especially hematologic malignancies and childhood sarcomas In addition to their diagnostic utility, chromosomal translocations are increasingly being used in the clinic to guide therapeutic decisions. However, the mechanisms which cause these translocations remain poorly understood. Illegit...

  16. Cohesin in determining chromosome architecture

    Energy Technology Data Exchange (ETDEWEB)

    Haering, Christian H., E-mail: christian.haering@embl.de [Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg (Germany); Jessberger, Rolf, E-mail: rolf.jessberger@tu-dresden.de [Institute of Physiological Chemistry, Dresden University of Technology, Dresden (Germany)

    2012-07-15

    Cells use ring-like structured protein complexes for various tasks in DNA dynamics. The tripartite cohesin ring is particularly suited to determine chromosome architecture, for it is large and dynamic, may acquire different forms, and is involved in several distinct nuclear processes. This review focuses on cohesin's role in structuring chromosomes during mitotic and meiotic cell divisions and during interphase.

  17. Genetics Home Reference: ring chromosome 20 syndrome

    Science.gov (United States)

    ... 3 links) Encyclopedia: Chromosome Encyclopedia: Epilepsy Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 20 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  18. Genetics Home Reference: ring chromosome 14 syndrome

    Science.gov (United States)

    ... Encyclopedia: Chromosome Health Topic: Developmental Disabilities Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 14 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  19. Bacterial chromosome organization and segregation.

    Science.gov (United States)

    Badrinarayanan, Anjana; Le, Tung B K; Laub, Michael T

    2015-01-01

    If fully stretched out, a typical bacterial chromosome would be nearly 1 mm long, approximately 1,000 times the length of a cell. Not only must cells massively compact their genetic material, but they must also organize their DNA in a manner that is compatible with a range of cellular processes, including DNA replication, DNA repair, homologous recombination, and horizontal gene transfer. Recent work, driven in part by technological advances, has begun to reveal the general principles of chromosome organization in bacteria. Here, drawing on studies of many different organisms, we review the emerging picture of how bacterial chromosomes are structured at multiple length scales, highlighting the functions of various DNA-binding proteins and the impact of physical forces. Additionally, we discuss the spatial dynamics of chromosomes, particularly during their segregation to daughter cells. Although there has been tremendous progress, we also highlight gaps that remain in understanding chromosome organization and segregation. PMID:26566111

  20. Higher order structure of chromosomes.

    Science.gov (United States)

    Okada, T A; Comings, D E

    1979-04-01

    Isolated Chinese hamster metaphase chromosomes were resuspended in 4 M ammonium acetate and spread on a surface of distilled water or 0.15 to 0.5 M ammonium acetate. The DNA was released in the form of a regular series of rosettes connected by interrossette DNA. The mean length of the rosette DNA was 14 micron, similar to the mean length of 10 micron for chromomere DNA of Drosophila polytene chromosomes. The mean interrosette DNA was 4.2 micron. SDS gel electrophoresis of the chromosomal nonhistone proteins showed them to be very similar to nuclear nonhistone proteins except for the presence of more actin and tubulin. Nuclear matrix proteins were present in the chromosomes and may play a role in forming the rosettes. Evidence that the rosette pattern is artifactual versus the possibility that it represents a real organizational substructure of the chromosomes is reviewed.

  1. Activated hydrotalcites as solid base catalysts in aldol condensations

    NARCIS (Netherlands)

    Roelofs, J.C.A.A.

    2002-01-01

    The development of new catalytic materials and routes to replace environmentally unacceptable processes in the fine chemical industry is emerging due to stringent legislation. Replacement of currently applied alkali bases in liquid-phase aldol condensations can result in diminishing of waste water s

  2. On the onset of surface condensation: formation and transition mechanisms of condensation mode

    Science.gov (United States)

    Sheng, Qiang; Sun, Jie; Wang, Qian; Wang, Wen; Wang, Hua Sheng

    2016-08-01

    Molecular dynamics simulations have been carried out to investigate the onset of surface condensation. On surfaces with different wettability, we snapshot different condensation modes (no-condensation, dropwise condensation and filmwise condensation) and quantitatively analyze their characteristics by temporal profiles of surface clusters. Two different types of formation of nanoscale droplets are identified, i.e. the formations with and without film-like condensate. We exhibit the effect of surface tensions on the formations of nanoscale droplets and film. We reveal the formation mechanisms of different condensation modes at nanoscale based on our simulation results and classical nucleation theory, which supplements the ‘classical hypotheses’ of the onset of dropwise condensation. We also reveal the transition mechanism between different condensation modes based on the competition between surface tensions and reveal that dropwise condensation represents the transition states from no-condensation to filmwise condensation.

  3. Condensed hydrogen for thermonuclear fusion

    International Nuclear Information System (INIS)

    Inertial confinement fusion (ICF) power, in either pure fusion or fission-fusion hybrid reactors, is a possible solution for future world's energy demands. Formation of uniform layers of a condensed hydrogen fuel in ICF targets has been a long standing materials physics challenge. Here, we review the progress in this field. After a brief discussion of the major ICF target designs and the basic properties of condensed hydrogens, we review both liquid and solid layering methods, physical mechanisms causing layer nonuniformity, growth of hydrogen single crystals, attempts to prepare amorphous and nanostructured hydrogens, and mechanical deformation behavior. Emphasis is given to current challenges defining future research areas in the field of condensed hydrogens for fusion energy applications.

  4. Capillary Condensation in Confined Media

    CERN Document Server

    Charlaix, Elisabeth

    2009-01-01

    We review here the physics of capillary condensation of liquids in confined media, with a special regard to the application in nanotechnologies. The thermodynamics of capillary condensation and thin film adsorption are first exposed along with all the relevant notions. The focus is then shifted to the modelling of capillary forces, to their measurements techniques (including SFA, AFM and crack tips) and to their influence on AFM imaging techniques as well as on the static and dynamic friction properties of solids (including granular heaps and sliding nanocontacts). A great attention is spent in investigating the delicate role of the surface roughness and all the difficulties involved in the reduction of the probe size to nanometric dimensions. Another major consequence of capillary condensation in nanosystems is the activation of several chemical and corrosive processes that can significantly alter the surface properties, such as dissolution/redeposition of solid materials and stress-corrosion crack propagati...

  5. Condensational theory of stationary tornadoes

    International Nuclear Information System (INIS)

    Using the Bernoulli integral for air streamline with condensing water vapor a stationary axisymmetric tornado circulation is described. The obtained profiles of vertical, radial and tangential velocities are in agreement with observations for the Mulhall tornado, world's largest on record and longest-lived among the three tornadoes for which 3D velocity data are available. Maximum possible vortex velocities are estimated. -- Highlights: → Water vapor condensation causes a logarithmic drop of air pressure towards tornado center. → The first ever theoretical description of tornado velocities is obtained. → The maximum vortex velocity grows logarithmically with decreasing tornado eye radius. → Air motion with high velocities can only develop in sufficiently large condensation areas.

  6. Identification of chromosome abnormalities in the horse using a panel of chromosome-specific painting probes generated by microdissection.

    Science.gov (United States)

    Bugno, Monika; Słota, Ewa; Pieńkowska-Schelling, Aldona; Schelling, Claude

    2009-09-01

    Fluorescent in situ hybridisation (FISH) using a panel of molecular probes for all chromosome pairs obtained by chromosome microdissection of the domestic horse ( Equus caballus ) was used to diagnose karyotype abnormalities in 35 horses (32 mares, 2 stallions and 1 intersex), which were selected for the study due to infertility (23 horses), reduced fertility (10 horses) and developmental anomalies (2 horses). The use of the FISH technique with probes for each horse chromosome pair enabled the diagnosis of many different chromosome aberrations in this population. Among the horses analysed, 21 animals had normal karyotype - 64,XX (19 mares) and 64,XY (2 stallions). Fourteen animals, constituting 40% of the population studied, showed the following chromosome abnormalities: 63,X (1 mare); 63,X/64,XX (6 mares); 63,X/64,XX/65,XXX (3 mares); 63,X/65,XXX (1 mare); 64,XX/65,XX+Xp (1 mare); 63,X/64,XX/65,XX+Xq (1 mare), and 63,X/64,XX/65,XX+delY (1 intersex). When only the mares studied because of complete infertility were taken into consideration, this proportion exceeded 56%. Due to the increased frequency of the above-mentioned aberrations in the mosaic form of two or more lines, it was necessary to analyse a large number (100-300) of metaphase spreads. The use of specific molecular probes obtained by chromosome microdissection made these diagnoses much easier.

  7. Visualization of the chromosome scaffold and intermediates of loop domain compaction in extracted mitotic cells.

    Science.gov (United States)

    Sheval, Eugene V; Polyakov, Vladimir Y

    2006-12-01

    A novel extraction protocol for cells cultured on coverslips is described. Observations of the extraction process in a perfusion chamber reveal that cells of all mitotic stages are not detached from coverslips during extraction, and all stages can be recognized using phase contrast images. We studied the extracted cell morphology and distribution of a major scaffold component - topoisomerase IIalpha, in extracted metaphase and anaphase cells. An extraction using 2M NaCl leads to destruction of chromosomes at the light microscope level. Immunogold studies demonstrate that the only residual structure observed is an axial chromosome scaffold that contains topoisomerase IIalpha. In contrast, mitotic chromosomes are swelled only partially after an extraction using dextran sulphate and heparin, and it appears that this treatment does not lead to total destruction of loop domains. In this case, the chromosome scaffold and numerous structures resembling small rosettes are revealed inside extracted cells. The rosettes observed condense after addition of Mg2+-ions and do not contain topoisomerase IIalpha suggesting that these structures correspond to intermediates of loop domain compaction. We propose a model of chromosome structure in which the loop domains are condensed into highly regular structures with rosette organization. PMID:17029868

  8. PRESANTATION OF A FAST TECHNICS FOR THE DESCRIPTION OF THE CHROMOSOMIC CHART OF A VEGETABLE SPECIES

    Directory of Open Access Journals (Sweden)

    Maria ABDUL HUSSAIN

    2004-07-01

    Full Text Available The caryologic technics aim to determine the level of polyploidy of a population or a species. The information brought for the knowledge of the chromosomal number of a species, is of various nature. Thus for several years the caryology has made it possible to better understand the taxonomy of a species, its tendencies evolutionary, its geographical distribution and the phenomena of its speciation [16]. Any time the chromosomal number, although being able to characterize a plant or a group of plants is not a character constant.It can vary inside a group, tribe, family or kind, and within same species[12,15,16]. The technics of identification of the most known chromosomes are: traditional technics based on the histological cut, the Technics of Feulgen which has like action to colour in purple red the DNA chromosomal [6,7,8] and technics of bands or mechanisms that it brings into play are related to the physicochemical properties of the chromatin and the condensed form of the chromosomes. To highlight the chromosomes of a species we observed somatic mitosis carried out bolsters of young roots. The principal stages of the technics has to follow are: the pretreatment, fixing, storage, the hydrolysis, colouring, the assembly and observation. All this work was completed on young roots of Solanum sodomeum L. or the number of the chromosome is still questioned.

  9. Turbulent mixing condensation nucleus counter

    Science.gov (United States)

    Mavliev, Rashid

    The construction and operating principles of the Turbulent Mixing Condensation Nucleus Counter (TM CNC) are described. Estimations based on the semiempirical theory of turbulent jets and the classical theory of nucleation and growth show the possibility of detecting particles as small as 2.5 nm without the interference of homogeneous nucleation. This conclusion was confirmed experimentally during the International Workshop on Intercomparison of Condensation Nuclei and Aerosol Particle Counters (Vienna, Austria). Number concentration, measured by the Turbulent Mixing CNC and other participating instruments, is found to be essentially equal.

  10. Minimum Leakage Condenser Test Program

    Energy Technology Data Exchange (ETDEWEB)

    1978-05-01

    This report presents the results and analysis of tests performed on four critical areas of large surface condensers: the tubes, tubesheets, tube/tubesheet joints and the water chambers. Significant changes in operation, service duty and the reliability considerations require that certain existing design criteria be verified and that improved design features be developed. The four critical areas were treated analytically and experimentally. The ANSYS finite element computer program was the basic analytical method and strain gages were used for obtaining experimental data. The results of test and analytical data are compared and recommendations made regarding potential improvement in condenser design features and analytical techniques.

  11. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the continued development of a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and...

  12. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and inversions) have profound genetic...

  13. Integral Reactor Containment Condensation Model and Experimental Validation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qiao [Oregon State Univ., Corvallis, OR (United States); Corradini, Michael [Univ. of Wisconsin, Madison, WI (United States)

    2016-05-02

    ranging from 4 to 21 bar with three different static inventories of non-condensable gas. Condensation and heat transfer rates were evaluated employing several methods, notably from measured temperature gradients in the HTP as well as measured condensate formation rates. A detailed mass and energy accounting was used to assess the various measurement methods and to support simplifying assumptions required for the analysis. Condensation heat fluxes and heat transfer coefficients are calculated and presented as a function of pressure to satisfy the objectives of this investigation. The major conclusions for those tests are summarized below: (1) In the steam blow-down tests, the initial condensation heat transfer process involves the heating-up of the containment heat transfer plate. An inverse heat conduction model was developed to capture the rapid transient transfer characteristics, and the analysis method is applicable to SMR safety analysis. (2) The average condensation heat transfer coefficients for different pressure conditions and non-condensable gas mass fractions were obtained from the integral test facility, through the measurements of the heat conduction rate across the containment heat transfer plate, and from the water condensation rates measurement based on the total energy balance equation. 15 (3) The test results using the measured HTP wall temperatures are considerably lower than popular condensation models would predict mainly due to the side wall conduction effects in the existing MASLWR integral test facility. The data revealed the detailed heat transfer characteristics of the model containment, important to the SMR safety analysis and the validation of associated evaluation model. However this approach, unlike separate effect tests, cannot isolate the condensation heat transfer coefficient over the containment wall, and therefore is not suitable for the assessment of the condensation heat transfer coefficient against system pressure and noncondensable

  14. Interspecific Y chromosome variation is sufficient to rescue hybrid male sterility and is influenced by the grandparental origin of the chromosomes.

    Science.gov (United States)

    Araripe, L O; Tao, Y; Lemos, B

    2016-06-01

    Y chromosomes display population variation within and between species. Co-evolution within populations is expected to produce adaptive interactions between Y chromosomes and the rest of the genome. One consequence is that Y chromosomes from disparate populations could disrupt harmonious interactions between co-evolved genetic elements and result in reduced male fertility, sterility or inviability. Here we address the contribution of 'heterospecific Y chromosomes' to fertility in hybrid males carrying a homozygous region of Drosophila mauritiana introgressed in the Drosophila simulans background. In order to detect Y chromosome-autosome interactions, which may go unnoticed in a single-species background of autosomes, we constructed hybrid genotypes involving three sister species: Drosophila simulans, D. mauritiana, and D. sechellia. These engineered strains varied due to: (i) species origin of the Y chromosome (D. simulans or D. sechellia); (ii) location of the introgressed D. mauritiana segment on the D. simulans third chromosome, and (iii) grandparental genomic background (three genotypes of D. simulans). We find complex interactions between the species origin of the Y chromosome, the identity of the D. mauritiana segment and the grandparental genetic background donating the chromosomes. Unexpectedly, the interaction of the Y chromosome and one segment of D. mauritiana drastically reduced fertility in the presence of Ysim, whereas the fertility is partially rescued by the Y chromosome of D. sechellia when it descends from a specific grandparental genotype. The restoration of fertility occurs in spite of an autosomal and X-linked genome that is mostly of D. simulans origin. These results illustrate the multifactorial basis of genetic interactions involving the Y chromosome. Our study supports the hypothesis that the Y chromosome can contribute significantly to the evolution of reproductive isolation and highlights the conditional manifestation of infertility in

  15. Tissue-specific differences in the spatial interposition of X-chromosome and 3R chromosome regions in the malaria mosquito Anopheles messeae Fall.

    Directory of Open Access Journals (Sweden)

    Gleb Artemov

    Full Text Available Spatial organization of a chromosome in a nucleus is very important in biology but many aspects of it are still generally unresolved. We focused on tissue-specific features of chromosome architecture in closely related malaria mosquitoes, which have essential inter-specific differences in polytene chromosome attachments in nurse cells. We showed that the region responsible for X-chromosome attachment interacts with nuclear lamina stronger in nurse cells, then in salivary glands cells in Anopheles messeae Fall. The inter-tissue differences were demonstrated more convincingly in an experiment of two distinct chromosomes interposition in the nucleus space of cells from four tissues. Microdissected DNA-probes from nurse cells X-chromosome (2BC and 3R chromosomes (32D attachment regions were hybridized with intact nuclei of nurse cells, salivary gland cells, follicle epithelium cells and imaginal disсs cells in 3D-FISH experiments. We showed that only salivary gland cells and follicle epithelium cells have no statistical differences in the interposition of 2BC and 32D. Generally, the X-chromosome and 3R chromosome are located closer to each other in cells of the somatic system in comparison with nurse cells on average. The imaginal disсs cell nuclei have an intermediate arrangement of chromosome interposition, similar to other somatic cells and nurse cells. In spite of species-specific chromosome attachments there are no differences in interposition of nurse cells chromosomes in An. messeae and An. atroparvus Thiel. Nurse cells have an unusual chromosome arrangement without a chromocenter, which could be due to the special mission of generative system cells in ontogenesis and evolution.

  16. Coherently Scattering Atoms from an Excited Bose-Einstein Condensate

    OpenAIRE

    Bijlsma, M.J.; Stoof, H.T.C.

    1999-01-01

    We consider scattering atoms from a fully Bose-Einstein condensed gas. If we take these atoms to be identical to those in the Bose-Einstein condensate, this scattering process is to a large extent analogous to Andreev reflection from the interface between a superconducting and a normal metal. We determine the scattering wave function in both the absence and the presence of a vortex. Our results show a qualitative difference between these two cases that can be understood as due to an Aharonov-...

  17. Primordial Universe with radiation and Bose-Einstein condensate

    CERN Document Server

    Alvarenga, F G; Fracalossi, R; Freitas, R C; Gonçalves, S V B; Monerat, G A; Oliveira-Neto, G; Silva, E V Corrêa

    2016-01-01

    In this work we derive a scenario where the early Universe consists of radiation and the Bose-Einstein condensate. We have included in our analysis the possibility of gravitational self-interaction due to the Bose-Einstein condensate being attractive or repulsive. After presenting the general structure of our model, we proceed to compute the finite-norm wave packet solutions to the Wheeler-DeWitt equation. The behavior of the scale factor is studied by applying the many-worlds interpretation of quantum mechanics. At the quantum level the cosmological model, in both attractive and repulsive cases, is free from the Big Bang singularity.

  18. High visibility gravimetry with a Bose-Einstein condensate

    CERN Document Server

    Debs, J E; Barter, T H; Döring, D; Dennis, G R; McDonald, G; Robins, N P; Close, J D

    2010-01-01

    We present results from an atomic gravimeter using a Bose-Einstein condensate with fringe visibility up to 85%. A direct comparison with a thermal state displays a significant increase in visibility for a condensed source. We do not observe any detrimental effects of atom-atom interactions, provided the cloud is allowed to reach the ballistic free-expansion regime. By increasing the space-time area enclosed by our interferometer using large-momentum-transfer beamsplitters, we achieve a precision of 17 ppm in a measurement of the local acceleration due to gravity.

  19. Evaporative Condensers in Comfortable Air Conditioning System

    Institute of Scientific and Technical Information of China (English)

    YIN Ying-de; ZHU Dong-sheng; DU Gui-mei; LI Yuan-xi; SUN He-jing; LIU Qing-ming

    2009-01-01

    The operating theory of an evaporative condenser was expatiated.The difference between an e-vaporative condensing refrigeration system and a general refrigeration system was analyzed.Compared with the air-cooled and the water-cooled,the virtues of energy-conservation and water-conservation of evaporative con-densers were analyzed.Some questions existing in the application of evaporative condensers were pointed out,the corresponding solving methods were analyzed accordingly,and the development trend of evaporative con-densing technique in mechanical refrigeration system field and the applied foreground of evaporative condensers in comfortable air conditioning were prospected.

  20. Immunolcocalization of actin in intact and DNA—and histone—depleted nuclei and chromosomes of allium cepa

    Institute of Scientific and Technical Information of China (English)

    WANLIHONG; MIAOXING

    1998-01-01

    The presence of actin in eukaryotic nuclei and chromosomes,and especially in higher plant nuclei and chromosomes,has not been well established.We detected actin in meristematic cells of Allium cepa with indirect immunofluorescence technique and observed bright fluorescence in the intact nuclei and chromosomes,indicating that actin is present in the nuclei and chromosomes of the higher plant.We labeld sections of the meristematic cells of A.cepa with immunogold technique,gold parti cles were concentrated in condensed chromatin and nucleoli,confirming the results of the immunofluoresence observations.We traeated the nuclei and chromosomes of A.cepa with DNase I and 2M NaCl and obtained DNA-and histone-depleted nuclei and chromosomes.Indirect immunofluorescence tests showed that the DNA-and histonedepleted nuclei and chromosomes reacted positively with the anti-actin antibodies.These results demonstrate that the anti-actin antibodies.These results demonstrate that actin exists not only in intact nuclei and chromosomes,but also in DNA-and histone-depleted nuclei and chrmosomes of the plant.In addition,our immuno-fluorescence tests indicate that tropomyosin is present in the nuclei and chromosomes of A.cepa.

  1. Formation of Chromosomal Domains by Loop Extrusion.

    Science.gov (United States)

    Fudenberg, Geoffrey; Imakaev, Maxim; Lu, Carolyn; Goloborodko, Anton; Abdennur, Nezar; Mirny, Leonid A

    2016-05-31

    Topologically associating domains (TADs) are fundamental structural and functional building blocks of human interphase chromosomes, yet the mechanisms of TAD formation remain unclear. Here, we propose that loop extrusion underlies TAD formation. In this process, cis-acting loop-extruding factors, likely cohesins, form progressively larger loops but stall at TAD boundaries due to interactions with boundary proteins, including CTCF. Using polymer simulations, we show that this model produces TADs and finer-scale features of Hi-C data. Each TAD emerges from multiple loops dynamically formed through extrusion, contrary to typical illustrations of single static loops. Loop extrusion both explains diverse experimental observations-including the preferential orientation of CTCF motifs, enrichments of architectural proteins at TAD boundaries, and boundary deletion experiments-and makes specific predictions for the depletion of CTCF versus cohesin. Finally, loop extrusion has potentially far-ranging consequences for processes such as enhancer-promoter interactions, orientation-specific chromosomal looping, and compaction of mitotic chromosomes. PMID:27210764

  2. Formation of Chromosomal Domains by Loop Extrusion

    Directory of Open Access Journals (Sweden)

    Geoffrey Fudenberg

    2016-05-01

    Full Text Available Topologically associating domains (TADs are fundamental structural and functional building blocks of human interphase chromosomes, yet the mechanisms of TAD formation remain unclear. Here, we propose that loop extrusion underlies TAD formation. In this process, cis-acting loop-extruding factors, likely cohesins, form progressively larger loops but stall at TAD boundaries due to interactions with boundary proteins, including CTCF. Using polymer simulations, we show that this model produces TADs and finer-scale features of Hi-C data. Each TAD emerges from multiple loops dynamically formed through extrusion, contrary to typical illustrations of single static loops. Loop extrusion both explains diverse experimental observations—including the preferential orientation of CTCF motifs, enrichments of architectural proteins at TAD boundaries, and boundary deletion experiments—and makes specific predictions for the depletion of CTCF versus cohesin. Finally, loop extrusion has potentially far-ranging consequences for processes such as enhancer-promoter interactions, orientation-specific chromosomal looping, and compaction of mitotic chromosomes.

  3. Gametocidal chromosomes enhancing chromosome aberration in common wheat induced by 5-azacytidine.

    Science.gov (United States)

    Su, W-Y; Cong, W-W; Shu, Y-J; Wang, D; Xu, G-H; Guo, C-H

    2013-01-01

    The gametocidal (Gc) chromosome from Aegilops spp induces chromosome mutation, which is introduced into common wheat as a tool of chromosome manipulation for genetic improvement. The Gc chromosome functions similar to a restriction-modification system in bacteria, in which DNA methylation is an important regulator. We treated root tips of wheat carrying Gc chromosomes with the hypomethylation agent 5-azacytidine; chromosome breakage and micronuclei were observed in these root tips. The frequency of aberrations differed in wheat containing different Gc chromosomes, suggesting different functions inducing chromosome breakage. Gc chromosome 3C caused the greatest degree of chromosome aberration, while Gc chromosome 3C(SAT) and 2C caused only slight chromosome aberration. Gc chromosome 3C induced different degrees of chromosome aberration in wheat varieties Triticum aestivum var. Chinese Spring and Norin 26, demonstrating an inhibition function in common wheat. PMID:23884766

  4. Hall Effect in spinor condensates

    OpenAIRE

    Taillefumier, Mathieu; Dahl, Eskil K.; Brataas, Arne; Hofstetter, Walter

    2009-01-01

    We consider a neutral spinor condensate moving in a periodic magnetic field. The spatially dependent magnetic field induces an effective spin dependent Lorentz force which in turn gives rise to a spin dependent Hall effect. Simulations of the Gross-Pitaevskii equation quantify the Hall effect. We discuss possible experimental realizations.

  5. Condensational theory of stationary tornadoes

    CERN Document Server

    Makarieva, Anastassia M; Nefiodov, Andrei V; 10.1016/j.physleta.2011.04.023

    2012-01-01

    Using the Bernoulli integral for air streamline with condensing water vapor a stationary axisymmetric tornado circulation is described. The obtained profiles of vertical, radial and tangential velocities are in agreement with observations for the Mulhall tornado, world's largest on record and longest-lived among the three tornadoes for which 3D velocity data are available. Maximum possible vortex velocities are estimated.

  6. Approaching Bose-Einstein Condensation

    Science.gov (United States)

    Ferrari, Loris

    2011-01-01

    Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial…

  7. Bogoliubov modes of a dipolar condensate in a cylindrical trap

    International Nuclear Information System (INIS)

    The calculation of properties of Bose-Einstein condensates with dipolar interactions has proven a computationally intensive problem due to the long range nature of the interactions, limiting the scope of applications. In particular, the lowest lying Bogoliubov excitations in three-dimensional harmonic trap with cylindrical symmetry were so far computed in an indirect way, by Fourier analysis of time-dependent perturbations, or by approximate variational methods. We have developed a very fast and accurate numerical algorithm based on the Hankel transform for calculating properties of dipolar Bose-Einstein condensates in cylindrically symmetric traps. As an application, we are able to compute many excitation modes by directly solving the Bogoliubov-De Gennes equations. We explore the behavior of the excited modes in different trap geometries. We use these results to calculate the quantum depletion of the condensate by a combination of a computation of the exact modes and the use of a local density approximation

  8. Condensing Unit with a Scroll Compressor (UB series)

    Energy Technology Data Exchange (ETDEWEB)

    Editor [Korea Energy Management Corporation, Yongin (Korea)

    2002-05-01

    Condensing unit, which is selected as a heat reservoir of grocery store or refrigerating warehouse, has increased its electricity consumption due to high annual operating ratio and large-sized stores. As the requirement of temperature management on freezing and storage has become strict for maintenance of food quality, the number of companies that import HACCP has increased for a few years. Accordingly, the requirement of high performance and reliability on a condensing unit has also risen more than it did. To meet the requirement, Mitsubishi Electric developed and sold condensing unit UB series, which has high reliability in energy saving. The company also has a plan to sell UPB series for the substitute refrigerant gas from fall of 2001. 5 figs., 2 tabs.

  9. Numerous transitions of sex chromosomes in Diptera.

    Directory of Open Access Journals (Sweden)

    Beatriz Vicoso

    2015-04-01

    Full Text Available Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot, but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes. Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa.

  10. Comparative sex chromosome genomics in snakes: differentiation, evolutionary strata, and lack of global dosage compensation.

    Directory of Open Access Journals (Sweden)

    Beatriz Vicoso

    Full Text Available Snakes exhibit genetic sex determination, with female heterogametic sex chromosomes (ZZ males, ZW females. Extensive cytogenetic work has suggested that the level of sex chromosome heteromorphism varies among species, with Boidae having entirely homomorphic sex chromosomes, Viperidae having completely heteromorphic sex chromosomes, and Colubridae showing partial differentiation. Here, we take a genomic approach to compare sex chromosome differentiation in these three snake families. We identify homomorphic sex chromosomes in boas (Boidae, but completely heteromorphic sex chromosomes in both garter snakes (Colubridae and pygmy rattlesnake (Viperidae. Detection of W-linked gametologs enables us to establish the presence of evolutionary strata on garter and pygmy rattlesnake sex chromosomes where recombination was abolished at different time points. Sequence analysis shows that all strata are shared between pygmy rattlesnake and garter snake, i.e., recombination was abolished between the sex chromosomes before the two lineages diverged. The sex-biased transmission of the Z and its hemizygosity in females can impact patterns of molecular evolution, and we show that rates of evolution for Z-linked genes are increased relative to their pseudoautosomal homologs, both at synonymous and amino acid sites (even after controlling for mutational biases. This demonstrates that mutation rates are male-biased in snakes (male-driven evolution, but also supports faster-Z evolution due to differential selective effects on the Z. Finally, we perform a transcriptome analysis in boa and pygmy rattlesnake to establish baseline levels of sex-biased expression in homomorphic sex chromosomes, and show that heteromorphic ZW chromosomes in rattlesnakes lack chromosome-wide dosage compensation. Our study provides the first full scale overview of the evolution of snake sex chromosomes at the genomic level, thus greatly expanding our knowledge of reptilian and vertebrate sex

  11. Familial transmission of a deletion of chromosome 21 derived from a translocation between chromosome 21 and an inverted chromosome 22.

    Science.gov (United States)

    Aviv, H; Lieber, C; Yenamandra, A; Desposito, F

    1997-06-27

    Chromosome analysis of a newborn boy with Down syndrome resulted in the identification of a family with an unusual derivative chromosome 22. The child has 46 chromosomes, including two chromosomes 21, one normal chromosome 22, and a derivative chromosome 22. Giemsa banding and fluorescent in situ hybridization (FISH) studies show that the derivative chromosome is chromosome 22 with evidence of both paracentric and pericentric inversions, joined to the long arm of chromosome 21 from 21q21.2 to qter. The rearrangement results in partial trisomy 21 extending from 21q21.2 to 21q terminus in the patient. The child's mother, brother, maternal aunt, and maternal grandmother are all carriers of the derivative chromosome. All have 45 chromosomes, with one normal chromosome 21, one normal chromosome 22, and the derivative chromosome 22. The rearrangement results in the absence of the short arm, the centromere, and the proximal long arm of chromosome 21 (del 21pter-21q21.2) in carriers. Carriers of the derivative chromosome in this family have normal physical appearance, mild learning disabilities and poor social adjustment. PMID:9182781

  12. Diagnosis of condensation-induced waterhammer: Methods and background

    International Nuclear Information System (INIS)

    This guidebook provides reference material and diagnostic procedures concerning condensation-induced waterhammer in nuclear power plants. Condensation-induced waterhammer is the most damaging form of waterhammer and its diagnosis is complicated by the complex nature of the underlying phenomena. In Volume 1, the guidebook groups condensation-induced waterhammers into five event classes which have similar phenomena and levels of damage. Diagnostic guidelines focus on locating the event center where condensation and slug acceleration take place. Diagnosis is described in three stages: an initial assessment, detailed evaluation and final confirmation. Graphical scoping analyses are provided to evaluate whether an event from one of the event classes could have occurred at the event center. Examples are provided for each type of waterhammer. Special instructions are provided for walking down damaged piping and evaluating damage due to waterhammer. To illustrate the diagnostic methods and document past experience, six case studies have been compiled in Volume 2. These case studies, based on actual condensation-induced waterhammer events at nuclear plants, present detailed data and work through the event diagnosis using the tools introduced in the first volume. 65 figs., 8 tabs

  13. Diagnosis of condensation-induced waterhammer: Case studies

    Energy Technology Data Exchange (ETDEWEB)

    Izenson, M.G.; Rothe, P.H.; Wallis, G.B.

    1988-10-01

    This guidebook provides reference material and diagnostic procedures concerning condensation-induced waterhammer in nuclear power plants. Condensation-induced waterhammer is the most damaging form of waterhammer, and its diagnosis is complicated by the complex nature of the underlying phenomena. In Volume 1, the guidebook groups condensation-induced waterhammers into five event classes which have similar phenomena and levels of damage. Diagnostic guidelines focus on locating the event center where condensation and slug acceleration take place. Diagnosis is described in three stages: an initial assessment, detailed evaluation and final confirmation. Graphical scoping analyses are provided to evaluate whether an event from one of the event classes could have occurred at the event center. Examples are provided for each type of waterhammer. Special instructions are provided for walking down damaged piping and evaluating damage due to waterhammer. To illustrate the diagnostic methods and document past experience, six case studies have been compiled in Volume 2. These case studies, based on actual condensation-induced waterhammer events at nuclear plants, present detailed data and work through the event diagnosis using the tools introduced in the first volume. 20 refs., 21 figs., 6 tabs.

  14. Investigation of viscosity of whole hydrolyze sweetened condensed milk

    Directory of Open Access Journals (Sweden)

    O. Kalinina

    2015-05-01

    Full Text Available Introduction. Рaper is aimed at developing of low-lactose (hydrolyzed sweetened condensed milk products technology for lactose intolerant people and for the whole population. Materials and methods: Rheological characteristics were determined on a Reotest device by the 2 nd method of viscometry Results and discussion. Reasonability of ß-galactosidase use for milk lactose hydrolyze during the production of canned products with sugar was proved in the previous works. This technology gives possibility to increase the quality of condensed canned foods, to reduce sugar concentration till 50 %, to increase dietary properties. Due to the reducing of saccharose mass part till 22 and 31 % the products had a liquid consistency that’s why was a necessity to increase the viscosity properties of condensed products. One of method to increase the product viscosity is inoculation of stabilization systems. Reasonability of the usage of stabilization system Bivicioc 1L was proved. The researches of viscosity determination in whole hydrolyzed sweetened condensed milk were shown in the work. Relations of viscosity of whole hydrolyzed condensed milk to the deformation rate were presented. Conclusions Viscosity indices of experimental samples in the fresh produced products and during storage are determined and justified.

  15. Meiosis and chromosome painting of sex chromosome systems in Ceboidea.

    Science.gov (United States)

    Mudry, M D; Rahn, I M; Solari, A J

    2001-06-01

    The identity of the chromosomes involved in the multiple sex system of Alouatta caraya (Aca) and the possible distribution of this system among other Ceboidea were investigated by chromosome painting of mitotic cells from five species and by analysis of meiosis at pachytene in two species. The identity of the autosome #7 (X2) involved in the multiple system of Aca and its breakage points were demonstrated by both meiosis and chromosome painting. These features are identical to those described by Consigliere et al. [1996] in Alouatta seniculus sara (Assa) and Alouatta seniculus arctoidea (Asar). This multiple system was absent in the other four Ceboidea species studied here. However, data from the literature strongly suggest the presence of this multiple in other members of this genus. The presence of this multiple system among several species and subspecies that show high levels of chromosome rearrangements may suggest a special selective value of this multiple. The meiotic features of the sex systems of Aca and Cebus apella paraguayanus (Cap) are strikingly different at pachytene, as the latter system is similar to the sex pair of man and other primates. The relatively large genetic distances between species presently showing this multiple system suggest that its origin is not recent. Other members of the same genus should be investigated at meiosis and by chromosome painting in order to know the extent and distribution of this complex sex-chromosome system. PMID:11376445

  16. Condensation energy of the superconducting bilayer cuprates

    Indian Academy of Sciences (India)

    Govind; Ajay; S K Joshi

    2002-05-01

    In the present work, we report the interplay of single particle and Cooper pair tunnelings on the superconducting state of layered high-c cuprate superconductors. For this we have considered a model Hamiltonian incorporating the intra-planar interactions and the contributions arising due to the coupling between the planes. The interplanar interactions include the single particle tunneling as well as the Josephson tunneling of Cooper pairs between the two layers. The expression of the out-of-plane correlation parameter which describes the hopping of a particle from one layer to another layer in the superconducting state is obtained within a Bardeen–Cooper–Schriefer (BCS) formalism using the Green’s function technique. This correlation is found to be sensitive to the various parameter of the model Hamiltonian. We have calculated the out-of-plane contribution to the superconducting condensation energy. The calculated values of condensation energy are in agreement with those obtained from the specific heat and the -axis penetration depth measurements on bilayer cuprates.

  17. Chromosome 12;15 rearrangements in patients with recurrent miscarriage

    Directory of Open Access Journals (Sweden)

    Nair S

    2006-01-01

    Full Text Available Background: An abnormal karyotype in either partner, especially featuring a translocation and/or inversion is considered to be a cause of recurrent miscarriages. It is generally assumed that recurrent miscarriage might be due to recurrent chromosomal abnormalities in the fetus due to a balanced aberration in one of the parents being inherited by the offspring in an unbalanced form. Aim: Evaluation of chromosomal rearrangements in couples with recurrent miscarriages. Materials and Methods: Peripheral blood was collected and lymphocyte cultures were set up. Slides prepared from the cell suspension were stained and screened for metaphases followed by karyotyping. Result: Balanced translocation was observed in the male partner in one case and in the female partners in the three other cases. Conclusion: Couples with recurrent miscarriage should be investigated for chromosomal rearrangements, thus helping in genetic counseling and providing the options for future pregnancies.

  18. Wall Condensation Modelling in Convective Flow

    OpenAIRE

    Lejon, Marcus

    2013-01-01

    Modelling condensation of water vapour is important in a number of engineering applications, such as nuclear reactor containment, rocket engine nozzles and heat exchangers. The current study investigates the possibilities of modelling condensation induced by a cold surface in a flow at high velocity and temperature. A number of non-condensable gases are present in the flow. The possibilities of condensation modelling are investigated in ANSYS CFX and ANSYS Fluent, with focus on ANSYS CFX. A c...

  19. Bose-Einstein condensation at constant temperature

    Science.gov (United States)

    Erhard, M.; Schmaljohann, H.; Kronjäger, J.; Bongs, K.; Sengstock, K.

    2004-09-01

    We present an experimental approach to Bose-Einstein condensation by increasing the particle number of the system at almost constant temperature. In particular, the emergence of a new condensate is observed in multicomponent F=1 spinor condensates of Rb87 . Furthermore, we develop a simple rate-equation model for multicomponent Bose-Einstein condensate thermodynamics at finite temperature which well reproduces the measured effects.

  20. Pion condensation and neutron star dynamics

    International Nuclear Information System (INIS)

    The question of formation of pion condensate via a phase transition in nuclear matter, especially in the core of neutron stars is reviewed. The possible mechanisms and the theoretical restrictions of pion condensation are summarized. The effects of ultradense equation of state and density jumps on the possible condensation phase transition are investigated. The possibilities of observation of condensation process are described. (D.Gy.)

  1. Entangled light from Bose-Einstein condensates

    OpenAIRE

    Ng, H. T.; Bose, S.

    2008-01-01

    We propose a method to generate entangled light with a Bose-Einstein condensate trapped in a cavity, a system realized in recent experiments. The atoms of the condensate are trapped in a periodic potential generated by a cavity mode. The condensate is continuously pumped by a laser and spontaneously emits a pair of photons of different frequencies in two distinct cavity modes. In this way, the condensate mediates entanglement between two cavity modes, which leak out and can be separated and e...

  2. Continuous droplet removal upon dropwise condensation of humid air on a hydrophobic micropatterned surface.

    Science.gov (United States)

    Zamuruyev, Konstantin O; Bardaweel, Hamzeh K; Carron, Christopher J; Kenyon, Nicholas J; Brand, Oliver; Delplanque, Jean-Pierre; Davis, Cristina E

    2014-08-26

    Combination of two physical phenomena, capillary pressure gradient and wettability gradient, allows a simple two-step fabrication process that yields a reliable hydrophobic self-cleaning condenser surface. The surface is fabricated with specific microscopic topography and further treatment with a chemically inert low-surface-energy material. This process does not require growth of nanofeatures (nanotubes) or hydrophilic-hydrophobic patterning of the surface. Trapezoidal geometry of the microfeatures facilitates droplet transfer from the Wenzel to the Cassie state and reduces droplet critical diameter. The geometry of the micropatterns enhances local coalescence and directional movement for droplets with diameter much smaller than the radial length of the micropatterns. The hydrophobic self-cleaning micropatterned condenser surface prevents liquid film formation and promotes continuous dropwise condensation cycle. Upon dropwise condensation, droplets follow a designed wettability gradient created with micropatterns from the most hydrophobic to the least hydrophobic end of the surface. The surface has higher condensation efficiency, due to its directional self-cleaning property, than a plain hydrophobic surface. We explain the self-actuated droplet collection mechanism on the condenser surface and demonstrate experimentally the creation of an effective wettability gradient over a 6 mm radial distance. In spite of its fabrication simplicity, the fabricated surface demonstrates self-cleaning property, enhanced condensation performance, and reliability over time. Our work enables creation of a hydrophobic condenser surface with the directional self-cleaning property that can be used for collection of biological (chemical, environmental) aerosol samples or for condensation enhancement.

  3. Continuous droplet removal upon dropwise condensation of humid air on a hydrophobic micropatterned surface.

    Science.gov (United States)

    Zamuruyev, Konstantin O; Bardaweel, Hamzeh K; Carron, Christopher J; Kenyon, Nicholas J; Brand, Oliver; Delplanque, Jean-Pierre; Davis, Cristina E

    2014-08-26

    Combination of two physical phenomena, capillary pressure gradient and wettability gradient, allows a simple two-step fabrication process that yields a reliable hydrophobic self-cleaning condenser surface. The surface is fabricated with specific microscopic topography and further treatment with a chemically inert low-surface-energy material. This process does not require growth of nanofeatures (nanotubes) or hydrophilic-hydrophobic patterning of the surface. Trapezoidal geometry of the microfeatures facilitates droplet transfer from the Wenzel to the Cassie state and reduces droplet critical diameter. The geometry of the micropatterns enhances local coalescence and directional movement for droplets with diameter much smaller than the radial length of the micropatterns. The hydrophobic self-cleaning micropatterned condenser surface prevents liquid film formation and promotes continuous dropwise condensation cycle. Upon dropwise condensation, droplets follow a designed wettability gradient created with micropatterns from the most hydrophobic to the least hydrophobic end of the surface. The surface has higher condensation efficiency, due to its directional self-cleaning property, than a plain hydrophobic surface. We explain the self-actuated droplet collection mechanism on the condenser surface and demonstrate experimentally the creation of an effective wettability gradient over a 6 mm radial distance. In spite of its fabrication simplicity, the fabricated surface demonstrates self-cleaning property, enhanced condensation performance, and reliability over time. Our work enables creation of a hydrophobic condenser surface with the directional self-cleaning property that can be used for collection of biological (chemical, environmental) aerosol samples or for condensation enhancement. PMID:25073014

  4. On nitrogen condensation in hypersonic nozzle flows: Numerical method and parametric study

    KAUST Repository

    Lin, Longyuan

    2013-12-17

    A numerical method for calculating two-dimensional planar and axisymmetric hypersonic nozzle flows with nitrogen condensation is developed. The classical nucleation theory with an empirical correction function and the modified Gyarmathy model are used to describe the nucleation rate and the droplet growth, respectively. The conservation of the liquid phase is described by a finite number of moments of the size distribution function. The moment equations are then combined with the Euler equations and are solved by the finite-volume method. The numerical method is first validated by comparing its prediction with experimental results from the literature. The effects of nitrogen condensation on hypersonic nozzle flows are then numerically examined. The parameters at the nozzle exit under the conditions of condensation and no-condensation are evaluated. For the condensation case, the static pressure, the static temperature, and the amount of condensed fluid at the nozzle exit decrease with the increase of the total temperature. Compared with the no-condensation case, both the static pressure and temperature at the nozzle exit increase, and the Mach number decreases due to the nitrogen condensation. It is also indicated that preheating the nitrogen gas is necessary to avoid the nitrogen condensation even for a hypersonic nozzle with a Mach number of 5 operating at room temperatures. © 2013 Springer-Verlag Berlin Heidelberg.

  5. Chromosome Architecture and Genome Organization

    OpenAIRE

    Giorgio Bernardi

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few...

  6. Chromosome evolution in Neotropical butterflies

    OpenAIRE

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O.; Brown, Keith S., Jr.

    2013-01-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results i...

  7. Methods for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1995-01-01

    Methods and compositions for chromosome-specific staining are provided. Compositions comprise heterogenous mixtures of labeled nucleic acid fragments having substantially complementary base sequences to unique sequence regions of the chromosomal DNA for which their associated staining reagent is specific. Methods include methods for making the chromosome-specific staining compositions of the invention, and methods for applying the staining compositions to chromosomes.

  8. Origin and domestication of papaya Yh chromosome

    Science.gov (United States)

    Sex in papaya is controlled by a pair of nascent sex chromosomes. Females are XX, and two slightly different Y chromosomes distinguish males (XY) and hermaphrodites (XYh). The hermaphrodite-specific region of the Yh chromosome (HSY) and its X chromosome counterpart were sequenced and analyzed previo...

  9. Unconditional generation of bright coherent non-Gaussian light from exciton-polariton condensates

    OpenAIRE

    Byrnes, Tim; Yamamoto, Yoshihisa; van Loock, Peter

    2012-01-01

    Exciton-polariton condensates are considered as a deterministic source of bright, coherent non-Gaussian light. Exciton-polariton condensates emit coherent light via the photoluminescence through the microcavity mirrors due to the spontaneous formation of coherence. Unlike conventional lasers which emit coherent Gaussian light, polaritons possess a natural nonlinearity due to the interaction of the excitonic component. This produces light with a negative component to the Wigner function at ste...

  10. Direct, nondestructive observation of a Bose condensate

    NARCIS (Netherlands)

    M.R. Andrews; M.O. Mewes; N.J. van Druten; D.S. Durfee; D.M. Kurn; W. Ketterle

    1996-01-01

    The spatial observation of a Bose condensate is reported. Dispersive light scattering was used to observe the separation between the condensed and normal components of the Bose gas inside a magnetic trap. This technique is nondestructive, and about a hundred images of the same condensate can be take

  11. Condensate from a two-stage gasifier

    DEFF Research Database (Denmark)

    Bentzen, Jens Dall; Henriksen, Ulrik Birk; Hindsgaul, Claus

    2000-01-01

    Condensate, produced when gas from downdraft biomass gasifier is cooled, contains organic compounds that inhibit nitrifiers. Treatment with activated carbon removes most of the organics and makes the condensate far less inhibitory. The condensate from an optimised two-stage gasifier is so clean t...

  12. Polymer induced condensation of dna supercoils

    NARCIS (Netherlands)

    Bessa Ramos Jr., J.E.; Ruggiero Neto, J.; Vries, de R.J.

    2008-01-01

    Macromolecular crowding is thought to be a significant factor driving DNA condensation in prokaryotic cells. Whereas DNA in prokaryotes is supercoiled, studies on crowding-induced DNA condensation have so far focused on linear DNA. Here we compare DNA condensation by poly(ethylene oxide) for superco

  13. Recombinant Chromosome 4 from a Familial Pericentric Inversion: Prenatal and Adulthood Wolf-Hirschhorn Phenotypes

    Directory of Open Access Journals (Sweden)

    Francesca Malvestiti

    2013-01-01

    Full Text Available Pericentric inversion of chromosome 4 can give rise to recombinant chromosomes by duplication or deletion of 4p. We report on a familial case of Wolf-Hirschhorn Syndrome characterized by GTG-banding karyotypes, FISH, and array CGH analysis, caused by a recombinant chromosome 4 with terminal 4p16.3 deletion and terminal 4q35.2 duplication. This is an aneusomy due to a recombination which occurred during the meiosis of heterozygote carrier of cryptic pericentric inversion. We also describe the adulthood and prenatal phenotypes associated with the recombinant chromosome 4.

  14. Condensation coefficient of water in a weak condensation state

    OpenAIRE

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-01-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises ...

  15. Chromosome evolution in Neotropical butterflies.

    Science.gov (United States)

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O; Brown, Keith S

    2013-06-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results in the context of chromosome numbers of over 1400 Neotropical butterfly species and subspecies derived from about 3000 populations published here and in earlier papers of a series. The overall results show that many Neotropical groups are characterized by karyotype instability with several derived modal numbers or none at all, while almost all taxa of Lepidoptera studied from the other parts of the world have one of n = 29-31 as modal numbers. Possibly chromosome number changes become fixed in the course of speciation driven by biotic interactions. Population subdivision and structuring facilitate karyotype change. Factors that stabilize chromosome numbers include hybridization among species sharing the same number, migration, sexual selection and possibly the distribution of chromosomes within the nucleus. PMID:23865963

  16. Numerically abnormal chromosome constitutions in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    Chapter 24, discusses numerically abnormal chromosome constitutions in humans. This involves abnormalities of human chromosome number, including polyploidy (when the number of sets of chromosomes increases) and aneuploidy (when the number of individual normal chromosomes changes). Chapter sections discuss the following chromosomal abnormalities: human triploids, imprinting and uniparental disomy, human tetraploids, hydatidiform moles, anomalies caused by chromosomal imbalance, 13 trisomy (D{sub 1} trisomy, Patau syndrome), 21 trisomy (Down syndrome), 18 trisomy syndrome (Edwards syndrome), other autosomal aneuploidy syndromes, and spontaneous abortions. The chapter concludes with remarks on the nonrandom participation of chromosomes in trisomy. 69 refs., 3 figs., 4 tabs.

  17. Origin of uranium isotope variations in early solar nebula condensates

    CERN Document Server

    Tissot, Francois L H; Grossman, Lawrence

    2016-01-01

    High temperature condensates found in meteorites display uranium isotopic variations (235U/238U) that complicate dating of the formation of the Solar System and whose origin remains mysterious. It is possible that these variations are due to decay of the short-lived radionuclide 247Cm (t1/2=15.6 Myr) into 235U but they could also be due to uranium kinetic isotopic fractionation during condensation. We report uranium isotope measurements of meteoritic refractory inclusions that reveal excesses of 235U reaching ~+6 % relative to average solar system composition, which can only be due to decay of 247Cm. This allows us to constrain the 247Cm/235U ratio at Solar System formation to (1.1 +- 0.3) x 10-4. This value provides new clues on the universality of nucleosynthetic r-process of rapid neutron capture.

  18. Origin of uranium isotope variations in early solar nebula condensates.

    Science.gov (United States)

    Tissot, François L H; Dauphas, Nicolas; Grossman, Lawrence

    2016-03-01

    High-temperature condensates found in meteorites display uranium isotopic variations ((235)U/(238)U), which complicate dating the solar system's formation and whose origin remains mysterious. It is possible that these variations are due to the decay of the short-lived radionuclide (247)Cm (t 1/2 = 15.6 My) into (235)U, but they could also be due to uranium kinetic isotopic fractionation during condensation. We report uranium isotope measurements of meteoritic refractory inclusions that reveal excesses of (235)U reaching ~+6% relative to average solar system composition, which can only be due to the decay of (247)Cm. This allows us to constrain the (247)Cm/(235)U ratio at solar system formation to (1.1 ± 0.3) × 10(-4). This value provides new clues on the universality of the nucleosynthetic r-process of rapid neutron capture.

  19. Origin of uranium isotope variations in early solar nebula condensates.

    Science.gov (United States)

    Tissot, François L H; Dauphas, Nicolas; Grossman, Lawrence

    2016-03-01

    High-temperature condensates found in meteorites display uranium isotopic variations ((235)U/(238)U), which complicate dating the solar system's formation and whose origin remains mysterious. It is possible that these variations are due to the decay of the short-lived radionuclide (247)Cm (t 1/2 = 15.6 My) into (235)U, but they could also be due to uranium kinetic isotopic fractionation during condensation. We report uranium isotope measurements of meteoritic refractory inclusions that reveal excesses of (235)U reaching ~+6% relative to average solar system composition, which can only be due to the decay of (247)Cm. This allows us to constrain the (247)Cm/(235)U ratio at solar system formation to (1.1 ± 0.3) × 10(-4). This value provides new clues on the universality of the nucleosynthetic r-process of rapid neutron capture. PMID:26973874

  20. Detection of dinoflagellates by the light scattering properties of the chiral structure of their chromosomes

    Science.gov (United States)

    Liu, Jianping; Kattawar, George W.

    2013-12-01

    One of the most prominent properties of dinoflagellates is their large sized and highly chromosome-laden nucleus, which contains dozens of cylindrically shaped chromosomes. With such high chromatic concentration, these chromosomes condense into ordered helical structures and were claimed to be responsible for the large circular polarization effects observed in the light scattering from dinoflagellates. In previous research, a thin helix model of a chromosome was used to compare the Discrete Dipole Approximation (DDA) and the analytical Born approximation calculations. However, for such a simplified model only modest qualitative agreements with experimental measurements were achieved. Moreover, only one chromosome in one nucleus was simulated, overlooking the effects of interactions between chromosomes. In this work, we adopt the helical plywood liquid crystal model with a capsule shape, in which parallel fibrils lie in plains perpendicular to the helix axis and the orientations of these fibrils twist at a constant angle between two neighboring layers. The ADDA code is applied to calculate the 16 Mueller matrix elements of light scattering from a single chromosome and from the nucleus, which is composed of a collection of randomly positioned and randomly orientated chromosomes. Special attention is paid to the S14 Mueller matrix element, which describes the ability of differentiating left and right circularly polarized light. Our results show that large S14 back scattering signals from the dinoflagellate nucleus results from the underlying helical structures of its chromosomes. These signals are sensitive to the light wavelength and pitch of the chromatic helix, the latter of which is species specific. Therefore, detecting back scattering S14 signal could be a promising method to monitor dinoflagellates such as Karenia brevis, the causal agent of the Florida red tide.

  1. Differential radio-sensitivities of human chromosomes 1 and 2 in one donor in interphase- and metaphase-spreads after 60Co γ-irradiation

    International Nuclear Information System (INIS)

    Radiation-induced chromosome aberrations lead to a plethora of detrimental effects at cellular level. Chromosome aberrations provide broad spectrum of information ranging from probability of malignant transformation to assessment of absorbed dose. Studies mapping differences in radiation sensitivities between human chromosomes are seldom undertaken. Consequently, health risk assessment based on radio-sensitivities of individual chromosomes may be erroneous. Our efforts in this article, attempt to demonstrate differences in radio-sensitivities of human chromosome-1 and/or -2, both in interphase and metaphase spreads. Upon blood collection, dosimetry and irradiation were performed. Lymphocytes were isolated after whole-blood irradiation with 60Co γ-rays in the dose range of 0–5 Gy for both interphase, and metaphase aberration studies. Induction of premature chromosome condensation in interphase cells was accomplished using a phosphatase inhibitor, calyculin-A. Metaphase spreads were harvested from short-term peripheral blood lymphocyte cultures following colcemid arrest and using an automated metaphase harvester and spreader. Aberration analysis in both interphase and metaphase spreads were done using FISH. In interphase, aberrant cell and aberration frequency involving chromosome 1 and/or 2 increased linearly with radiation dose. In metaphase, aberrations increased in a linear-quadratic manner with dose. Our studies ascertain that chromosome-2 is more radio-sensitive than chromosome-1 in both interphase and metaphase stages, albeit the DNA content of chromosome-2 is lesser than chromosome-1 by almost 10 million base pairs. Differences in radio-sensitivities of chromosomes have implications in genetic damage, chromosome organization, and chromosome function. Designing research experiments based on our vital findings may bring benefit to radiation-induced risk assessment, therapeutics and development of chromosome specific biomarkers

  2. Evaluation of radiosensitivity of human tumor cells after irradiation of γ-rays based on G2-chromosome aberrations

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The aim of the present investigation is to determine initial G2-chromosome aberrations and to validate whether the G2-chromosome aberrations can predict the cellular clonogenic survival in human tumor cell lines. Cell lines of human ovary carcinoma cells (HO8910) and human hepatoma cells (HepG2) were irradiated with a range of doses and assessed both for initial G2-chromosome aberrations and for cell survival after γ-irradiation. The initial G2-chromosome aberrations were measured by counting the number of G2-chromatid breaks after irradiation, detected by the premature chromosome condensation technique, and the G2-assay method. Cell survival was documented by a colony formation assay. A linear-quadratic survival curve was observed in both cell lines. The dose-response results show that the numbers of G2-chromatid breaks increase with the increase in dose in the two cell lines. At higher doses (higher than 4 Gy) of irradiation, the number of G2-chromatid breaks for the G2-assay method cannot be determined because too few cells reach mitosis, and hence their detection is difficult. A good correlation is found between the clonogenic survival and the radiation-induced initial G2-chromatid breaks per cell (r=0.9616). The present results suggest that the premature chromosome condensation technique may be useful for determining chromatid breaks in G2 cells, and the number of initial G2-chromatid breaks holds promise for predicting the radiosensitivity of tumor cells.

  3. Y-chromosomal genes affecting male fertility: A review

    Science.gov (United States)

    Dhanoa, Jasdeep Kaur; Mukhopadhyay, Chandra Sekhar; Arora, Jaspreet Singh

    2016-01-01

    The mammalian sex-chromosomes (X and Y) have evolved from autosomes and are involved in sex determination and reproductive traits. The Y-chromosome is the smallest chromosome that consists of 2-3% of the haploid genome and may contain between 70 and 200 genes. The Y-chromosome plays major role in male fertility and is suitable to study the evolutionary relics, speciation, and male infertility and/or subfertility due to its unique features such as long non-recombining region, abundance of repetitive sequences, and holandric inheritance pattern. During evolution, many holandric genes were deleted. The current review discusses the mammalian holandric genes and their functions. The commonly encountered infertility and/or subfertility problems due to point or gross mutation (deletion) of the Y-chromosomal genes have also been discussed. For example, loss or microdeletion of sex-determining region, Y-linked gene results in XY males that exhibit female characteristics, deletion of RNA binding motif, Y-encoded in azoospermic factor b region results in the arrest of spermatogenesis at meiosis. The holandric genes have been covered for associating the mutations with male factor infertility. PMID:27536043

  4. Condensed matter analogues of cosmology

    Science.gov (United States)

    Kibble, Tom; Srivastava, Ajit

    2013-10-01

    It is always exciting when developments in one branch of physics turn out to have relevance in a quite different branch. It would be hard to find two branches farther apart in terms of energy scales than early-universe cosmology and low-temperature condensed matter physics. Nevertheless ideas about the formation of topological defects during rapid phase transitions that originated in the context of the very early universe have proved remarkably fruitful when applied to a variety of condensed matter systems. The mathematical frameworks for describing these systems can be very similar. This interconnection has led to a deeper understanding of the phenomena in condensed matter systems utilizing ideas from cosmology. At the same time, one can view these condensed matter analogues as providing, at least in a limited sense, experimental access to the phenomena of the early universe for which no direct probe is possible. As this special issue well illustrates, this remains a dynamic and exciting field. The basic idea is that when a system goes through a rapid symmetry-breaking phase transition from a symmetric phase into one with spontaneously broken symmetry, the order parameter may make different choices in different regions, creating domains that when they meet can trap defects. The scale of those domains, and hence the density of defects, is constrained by the rate at which the system goes through the transition and the speed with which order parameter information propagates. This is what has come to be known as the Kibble-Zurek mechanism. The resultant scaling laws have now been tested in a considerable variety of different systems. The earliest experiments illustrating the analogy between cosmology and condensed matter were in liquid crystals, in particular on the isotropic-to-nematic transition, primarily because it is very easy to induce the phase transition (typically at room temperature) and to image precisely what is going on. This field remains one of the

  5. The Chromosome Microdissection and Microcloning Technique.

    Science.gov (United States)

    Zhang, Ying-Xin; Deng, Chuan-Liang; Hu, Zan-Min

    2016-01-01

    Chromosome microdissection followed by microcloning is an efficient tool combining cytogenetics and molecular genetics that can be used for the construction of the high density molecular marker linkage map and fine physical map, the generation of probes for chromosome painting, and the localization and cloning of important genes. Here, we describe a modified technique to microdissect a single chromosome, paint individual chromosomes, and construct single-chromosome DNA libraries. PMID:27511173

  6. Evolution of Sex Chromosomes in Insects

    OpenAIRE

    Kaiser, Vera B; Bachtrog, Doris

    2010-01-01

    Sex chromosomes have many unusual features relative to autosomes. Y (or W) chromosomes lack genetic recombination, are male- (female-) limited, and show an abundance of genetically inert heterochromatic DNA but contain few functional genes. X (or Z) chromosomes also show sex-biased transmission (i.e., X chromosomes show female-biased and Z-chromosomes show male-biased inheritance) and are hemizygous in the heterogametic sex. Their unusual ploidy level and pattern of inheritance imply that sex...

  7. Role of antikaon condensation in r-mode instability

    CERN Document Server

    Chatterjee, Debarati

    2007-01-01

    We investigate the effect of antikaon condensed matter on bulk viscosity in rotating neutron stars. We use relativistic field theoretical models to construct the equation of state of neutron stars with the condensate, where the phase transition from nucleonic to $K^-$ condensed phase is assumed to be of first order. We calculate the coefficient of bulk viscosity due to the non-leptonic weak interaction n --> p + K^-. The influence of antikaon bulk viscosity on the gravitational radiation reaction driven instability in the r-modes is investigated. We compare our results with the previously studied non-leptonic weak interaction $n + p --> p + \\Lambda$ involving hyperons on the damping of the r-mode oscillations. We find that the bulk viscosity coefficient due to the non-leptonic weak process involving the condensate is suppressed by several orders of magnitude in comparison with the non-superfluid hyperon bulk viscosity coefficient. Consequently, the antikaon bulk viscosity may not be able to damp the r-mode in...

  8. Chiral Condensate and Mott-Anderson Freeze-Out

    International Nuclear Information System (INIS)

    We present the idea of a Mott-Anderson freeze-out that suggests a key role of the localization of the hadron wave functions when traversing the hadronization transition. The extension of hadron wave functions in dense matter is governed by the behavior of the chiral quark condensate such that its melting at finite temperatures and chemical potentials entails an increase of the size of hadrons and thus their geometrical strong interaction cross sections. It is demonstrated within a schematic resonance gas model, that a kinetic freeze-out condition reveals a correlation with the reduction of the chiral condensate in the phase diagram up to 50% of its vacuum value. Generalizing the description of the chiral condensate by taking into account a full hadron resonance gas such correlation gets distorted. We discuss, that this may be due to our approximations in calculating the chiral condensate which disregard both, in-medium effects on hadron masses and hadron-hadron interactions. The latter, in particular due to quark exchange reactions, could lead to a delocalization of the hadron wave functions in accordance with the picture of a Mott-Anderson transition. (author)

  9. Condensation of the air-steam mixture in a vertical tube condenser

    OpenAIRE

    Havlík Jan; Dlouhý Tomáš

    2016-01-01

    This paper deals with the condensation of water vapour in the presence of non-condensable air. Experimental and theoretical solutions of this problem are presented here. A heat exchanger for the condensation of industrial waste steam containing infiltrated air was designed. The condenser consists of a bundle of vertical tubes in which the steam condenses as it flows downwards with cooling water flowing outside the tubes in the opposite direction. Experiments with pure steam and with mixtures ...

  10. Perturbing a quantum gravity condensate

    CERN Document Server

    Gielen, Steffen

    2014-01-01

    In a recent proposal using the group field theory (GFT) approach, a spatially homogeneous (generally anisotropic) universe is described as a quantum gravity condensate of 'atoms of space', which allows the derivation of an effective cosmological Friedmann equation from the microscopic quantum gravity dynamics. Here we take a first step towards the study of cosmological perturbations over the homogeneous background. We consider a state in which a single 'atom' is added to an otherwise homogeneous condensate. Backreaction of the perturbation on the background is negligible and the background dynamics can be solved separately. The dynamics for the perturbation takes the form of a quantum cosmology Hamiltonian for a 'wavefunction', depending on background and perturbations, of the product form usually assumed in a Born-Oppenheimer approximation. The perturbation we consider can then be interpreted as a spatially homogeneous metric perturbation. For this case, our results show how perturbations can be added to con...

  11. Fundamentals of condensed matter physics

    CERN Document Server

    Cohen, Marvin L

    2016-01-01

    Based on an established course and covering the fundamentals, central areas, and contemporary topics of this diverse field, Fundamentals of Condensed Matter Physics is a much-needed textbook for graduate students. The book begins with an introduction to the modern conceptual models of a solid from the points of view of interacting atoms and elementary excitations. It then provides students with a thorough grounding in electronic structure as a starting point to understand many properties of condensed matter systems - electronic, structural, vibrational, thermal, optical, transport, magnetic and superconductivity - and methods to calculate them. Taking readers through the concepts and techniques, the text gives both theoretically and experimentally inclined students the knowledge needed for research and teaching careers in this field. It features 200 illustrations, 40 worked examples and 150 homework problems for students to test their understanding. Solutions to the problems for instructors are available at w...

  12. Polymer Bose–Einstein condensates

    Energy Technology Data Exchange (ETDEWEB)

    Castellanos, E., E-mail: ecastellanos@fis.cinvestav.mx [Departamento de Física, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, A.P. 14-740, México D.F. 07000 (Mexico); Chacón-Acosta, G., E-mail: gchacon@correo.cua.uam.mx [Departamento de Matemáticas Aplicadas y Sistemas, Universidad Autónoma Metropolitana-Cuajimalpa, Artificios 40, México D.F. 01120 (Mexico)

    2013-05-13

    In this work we analyze a non-interacting one-dimensional polymer Bose–Einstein condensate in a harmonic trap within the semiclassical approximation. We use an effective Hamiltonian coming from the polymer quantization that arises in loop quantum gravity. We calculate the number of particles in order to obtain the critical temperature. The Bose–Einstein functions are replaced by series, whose high order terms are related to powers of the polymer length. It is shown that the condensation temperature presents a shift respect to the standard case, for small values of the polymer scale. In typical experimental conditions, it is possible to establish a bound for λ{sup 2} up to ≲10{sup −16} m{sup 2}. To improve this bound we should decrease the frequency of the trap and also decrease the number of particles.

  13. Compact heat exchangers modeling: Condensation

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Cascales, J.R.; Vera-Garcia, F. [Technical University of Cartagena, Thermal and Fluid Engineering Department, C/Dr. Fleming, s/n 30202 Cartagena, Murcia (Spain); Gonzalvez-Macia, J.; Corberan-Salvador, J.M. [Technical University of Valencia, Applied Thermodynamic Department, Valencia (Spain); Johnson, M.W.; Kohler, G.T. [Modine Manufacturing Company, Commercial Products Group, Racine, WI (United States)

    2010-01-15

    A model for the analysis of compact heat exchangers working as either evaporators or condensers is presented. This paper will focus exclusively on condensation modeling. The model is based on cell discretization of the heat exchanger in such a way that cells are analyzed following the path imposed by the refrigerant flowing through the tubes. It has been implemented in a robust code developed for assisting with the design of compact heat exchangers and refrigeration systems. These heat exchangers consist of serpentine fins that are brazed to multi-port tubes with internal microchannels. This paper also investigates a number of correlations used for the calculation of the refrigerant side heat transfer coefficient. They are evaluated comparing the predicted data with the experimental data. The working fluids used in the experiments are R134a and R410A, and the secondary fluid is air. The experimental facility is briefly described and some conclusions are finally drawn. (author)

  14. Optimized wood/pellet heater with flue gas condensation; Optimerad ved/pelletspanna med roekgaskondensering

    Energy Technology Data Exchange (ETDEWEB)

    Fredriksson, Christian; Ramstroem, Erik; Berge, Niklas [TPS Termiska Processer AB, Nykoeping (Sweden)

    2002-09-01

    To increase the efficiency of small-scale combustion equipment it is possible to cool the flue gas and condense the water vapor in the flue gas in a flue gas condenser. This also makes it possible to reduce the emissions of particles and unburnt hydrocarbon if the condenser is designed in a suitable way. This work concerns flue gas condensation with respect to the design of the condenser, the handling of the condensate and the integration of the flue gas condenser in a heating system from a technical and an economical point of view. The results from laboratory experiments shows that a flue gas condenser, designed as a plate heat exchanger, connected to a wood pellet fired heater reduces the emissions of both particles and unburnt hydrocarbons. A reduction of 10 to 77% of the particle content in the gas was achieved, the content of hydrocarbons (BTX) was reduced by 50 to 91 %. It was not possible to see any effect on the emissions by changing the design of the condenser, due to the relatively large scatter in the determined particle content in the gas. When it comes to cooling capacity the trends were however more clear; the cooling capacity was strongly dependent on the design of the condenser. It was possible to increase the cooling capacity of the condenser with 124% by changing the condenser design from a reference case with conventional design of the condenser with flat walls, to a design with a corrugated shape of the wall. For a typical domestic wood stove heater of 30 kW this means that the cooling capacity in a condenser under similar conditions increases from 3.3 to 7.4 kW. The addition of water in a spray in the gas upstream of the condenser had only a limited effect on the cooling capacity. The condensate from the condenser was analyzed with respect to the components that currently are regulated for disposal to the district sewer system. The analyses showed that the condensate most likely could be disposed to the sewer system directly without any

  15. Quality factors to consider in condensate selection

    Energy Technology Data Exchange (ETDEWEB)

    Lywood, B. [Crude Quality Inc., Edmonton, AB (Canada)

    2009-07-01

    Many factors must be considered when assessing the feasibility of using condensates as a diluent for bitumen or heavy crude production blending. In addition to commercial issues, the effect of condensate quality is a key consideration. In general, condensate quality refers to density and viscosity. However, valuation decisions could be enhanced through the expansion of quality definitions and understanding. This presentation focused on the parameters that are important in choosing a diluent grade product. It also reviewed pipeline and industry specifications and provided additional information regarding general properties for bitumen and condensate compatibility; sampling and quality testing needs; and existing sources of information regarding condensate quality. tabs., figs.

  16. Advances in condensed matter optics

    CERN Document Server

    Chen, Liangyao; Jiang, Xunya; Jin, Kuijuan; Liu, Hui; Zhao, Haibin

    2015-01-01

    This book describes some of the more recent progresses and developmentsin the study of condensed matter optics in both theoretic and experimental fields.It will help readers, especially graduate students and scientists who are studying and working in the nano-photonic field, to understand more deeply the characteristics of light waves propagated in nano-structure-based materials with potential applications in the future.

  17. Atomistic modeling of dropwise condensation

    Science.gov (United States)

    Sikarwar, B. S.; Singh, P. L.; Muralidhar, K.; Khandekar, S.

    2016-05-01

    The basic aim of the atomistic modeling of condensation of water is to determine the size of the stable cluster and connect phenomena occurring at atomic scale to the macroscale. In this paper, a population balance model is described in terms of the rate equations to obtain the number density distribution of the resulting clusters. The residence time is taken to be large enough so that sufficient time is available for all the adatoms existing in vapor-phase to loose their latent heat and get condensed. The simulation assumes clusters of a given size to be formed from clusters of smaller sizes, but not by the disintegration of the larger clusters. The largest stable cluster size in the number density distribution is taken to be representative of the minimum drop radius formed in a dropwise condensation process. A numerical confirmation of this result against predictions based on a thermodynamic model has been obtained. Results show that the number density distribution is sensitive to the surface diffusion coefficient and the rate of vapor flux impinging on the substrate. The minimum drop radius increases with the diffusion coefficient and the impinging vapor flux; however, the dependence is weak. The minimum drop radius predicted from thermodynamic considerations matches the prediction of the cluster model, though the former does not take into account the effect of the surface properties on the nucleation phenomena. For a chemically passive surface, the diffusion coefficient and the residence time are dependent on the surface texture via the coefficient of friction. Thus, physical texturing provides a means of changing, within limits, the minimum drop radius. The study reveals that surface texturing at the scale of the minimum drop radius does not provide controllability of the macro-scale dropwise condensation at large timescales when a dynamic steady-state is reached.

  18. Radiative corrections to Bose condensation

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, A. (Academia de Ciencias de Cuba, La Habana. Inst. de Matematica, Cibernetica y Computacion)

    1985-04-01

    The Bose condensation of the scalar field in a theory behaving in the Coleman-Weinberg mode is considered. The effective potential of the model is computed within the semiclassical approximation in a dimensional regularization scheme. Radiative corrections are shown to introduce certain ..mu..-dependent ultraviolet divergences in the effective potential coming from the Many-Particle theory. The weight of radiative corrections in the dynamics of the system is strongly modified by the charge density.

  19. Spacetime geometry from graviton condensation

    OpenAIRE

    Zielinski, Sophia

    2016-01-01

    In this thesis we introduce a novel approach viewing spacetime geometry as an emergent phenomenon based on the condensation of a large number of quanta on a distinguished flat background. We advertise this idea with regard to investigations of spacetime singularities within a quantum field theoretical framework and semiclassical considerations of black holes. Given that in any physical theory apart from General Relativity the metric background is determined in advance, singu...

  20. Theory of laminar film condensation

    CERN Document Server

    Fujii, Tetsu

    1991-01-01

    Since the petroleum crisis in the 1970s, a lot of effort to save energy was made in industry, and remarkable achievements have been made. In the research and development concerning thermal energy, however, it was clar­ ified that one of the most important problems was manufacturing con­ densing systems with smaller size and higher performance. To solve this problem we need a method which synthesizes selections_ of the type of con­ denser, cooling tube and its arrangement, assessment of fouling on the cooling surfaces, consideration of transient characteristics of a condenser, etc. The majority of effort, however, has been to devise a surface element which enhances the heat transfer coefficient in condensation of a single or multicomponent vapor. Condensation phenomena are complexly affected by a lot of physical property values, and accordingly the results of theo­ retical research are expressed with several dimensionless parameters. On the other hand, the experimental research is limited to those with som...

  1. Proteomics Analysis with a Nano Random Forest Approach Reveals Novel Functional Interactions Regulated by SMC Complexes on Mitotic Chromosomes.

    Science.gov (United States)

    Ohta, Shinya; Montaño-Gutierrez, Luis F; de Lima Alves, Flavia; Ogawa, Hiromi; Toramoto, Iyo; Sato, Nobuko; Morrison, Ciaran G; Takeda, Shunichi; Hudson, Damien F; Rappsilber, Juri; Earnshaw, William C

    2016-08-01

    Packaging of DNA into condensed chromosomes during mitosis is essential for the faithful segregation of the genome into daughter nuclei. Although the structure and composition of mitotic chromosomes have been studied for over 30 years, these aspects are yet to be fully elucidated. Here, we used stable isotope labeling with amino acids in cell culture to compare the proteomes of mitotic chromosomes isolated from cell lines harboring conditional knockouts of members of the condensin (SMC2, CAP-H, CAP-D3), cohesin (Scc1/Rad21), and SMC5/6 (SMC5) complexes. Our analysis revealed that these complexes associate with chromosomes independently of each other, with the SMC5/6 complex showing no significant dependence on any other chromosomal proteins during mitosis. To identify subtle relationships between chromosomal proteins, we employed a nano Random Forest (nanoRF) approach to detect protein complexes and the relationships between them. Our nanoRF results suggested that as few as 113 of 5058 detected chromosomal proteins are functionally linked to chromosome structure and segregation. Furthermore, nanoRF data revealed 23 proteins that were not previously suspected to have functional interactions with complexes playing important roles in mitosis. Subsequent small-interfering-RNA-based validation and localization tracking by green fluorescent protein-tagging highlighted novel candidates that might play significant roles in mitotic progression. PMID:27231315

  2. Effect of Vapor Flow on Jumping Droplets during Condensation on Superhydrophobic Surfaces

    Science.gov (United States)

    Preston, Daniel J.; Miljkovic, Nenad; Enright, Ryan; Limia, Alexander; Wang, Evelyn N.

    2013-11-01

    Upon coalescence of droplets on a superhydrophobic surface, the net reduction in droplet surface area results in a release of surface energy that can cause the coalesced droplet to ``jump'' away from the surface. Jumping condensing surfaces have been shown to enhance condensation heat transfer by up to 30% compared to state-of-the-art dropwise condensing surfaces. While the heat transfer enhancement of jumping condensation is well documented, droplet behavior after departure from the surface has not been considered. Vapor flows to the condensing surface due to mass conservation. This flow can increase drag on departing droplets, resulting in complete droplet reversal and return to the surface. Upon return, these larger droplets impede heat transfer until they jump again or finally shed due to gravity. By characterizing individual droplet trajectories during condensation on hydrophobic nanostructured copper oxide surfaces for a variety of heat fluxes (q'' = 0.1 - 2 W/cm2), we showed that vapor flow entrainment dominates droplet motion for droplets smaller than R ~ 30 um at high heat fluxes (q'' >2 W/cm2). Furthermore, we developed an analytical model of droplet motion based on first principles and the Reynolds drag equation which agreed well with the experimental data. We considered condensation on both flat and tubular geometries with our model, and we suggest avenues to further enhance heat transfer which minimize droplet return due to entrainment.

  3. Inherited unbalanced structural chromosome abnormalities at prenatal chromosome analysis are rarely ascertained through recurrent miscarriage

    NARCIS (Netherlands)

    Franssen, M. T. M.; Korevaar, J. C.; Tjoa, W. M.; Leschot, N. J.; Bossuyt, P. M. M.; Knegt, A. C.; Suykerbuyk, R. F.; Hochstenbach, R.; van der Veen, F.; Goddijn, M.

    2008-01-01

    Objective To determine the mode of ascertainment of inherited unbalanced structural chromosome abnormalities detected at prenatal chromosome analysis. Methods From the databases of three centres for clinical genetics in the Netherlands, all cases of inherited unbalanced structural chromosome abnorma

  4. Chromosomal evolution among leaf-nosed nectarivorous bats – evidence from cross-species chromosome painting (Phyllostomidae, Chiroptera)

    OpenAIRE

    Sotero-Caio, Cibele G.; Volleth, Marianne; Gollahon, Lauren S; Fu, Beiyuan; Cheng, William; Ng, Bee L.; Yang, Fengtang; Baker, Robert J.

    2013-01-01

    Background New World leaf-nosed bats, Phyllostomidae, represent a lineage of Chiroptera marked by unprecedented morphological/ecological diversity and extensive intergeneric chromosomal reorganization. There are still disagreements regarding their systematic relationships due to morphological convergence among some groups. Their history of karyotypic evolution also remains to be documented. Results To better understand the evolutionary relationships within Phyllostomidae, we developed chromos...

  5. Droplet condensation and growth on nanotextured surfaces impregnated with an immiscible liquid

    Science.gov (United States)

    Anand, Sushant; Paxson, Adam; Smith, Jonathan; Dhiman, Rajeev; Varanasi, Kripa

    2012-02-01

    For effective dropwise condensation, a surface that sheds droplets easily is desirable due to the enhancement in accompanying heat transfer. Incorporating nano-textures on the surface can enhance the droplet shedding or spreading. We demonstrate that droplet shedding can be further influenced by impregnating the nano-textured surface with a liquid which is immiscible with respect to the droplet. In this study, the dynamics of dropwise condensation on such immiscible liquid impregnated nano-textured surfaces have been investigated in pure quiescent water vapor conditions. Condensation experiments were conducted using an Environmental Scanning Electron Microscope by controlling the chamber water vapor pressure and substrate temperature. We show preferential sites for condensation and different modes under which droplets grow, depending upon the surface chemistry, surface texture, and the impregnating liquid properties. Concurrently, we show an evolution of apparent contact angles during the condensation process on the impregnated surfaces.

  6. Failure of Titanium Condenser Tubes after 24 Years Power Plant Service

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Enemark, Allan; Hangaard, Anders

    2014-01-01

    The titanium condenser has been in operation for 24 years at Amager unit 3 power plant. In February 2012, the plant was contaminated by seawater due to a failed condenser tube and some tubes were plugged. A month later, the plant tripped again. Small leaks were found again and finally approx. 200...... tubes were plugged before the condenser was in service again. A series of inspections, NDT, and destructive examinations were conducted to try and understand the cause of failure in the tubes within the condenser. After such investigations, degradation mechanisms such as inner fouling, steam impingement......, and fretting/erosion around the supports could be discounted. Ductile cracks were found in the tube within the tubesheet. From circumstantial evidence, it was concluded that failure was caused by a semi-filled condenser which led to a mismatch in expansion coefficients of filled tubes and unfilled...

  7. New Advances in Chromosome Architecture.

    Science.gov (United States)

    Leake, Mark C

    2016-01-01

    Our knowledge of the "architecture" of chromosomes has grown enormously in the past decade. This new insight has been enabled largely through advances in interdisciplinary research methods at the cutting-edge interface of the life and physical sciences. Importantly this has involved several state-of-the-art biophysical tools used in conjunction with molecular biology approaches which enable investigation of chromosome structure and function in living cells. Also, there are new and emerging interfacial science tools which enable significant improvements to the spatial and temporal resolution of quantitative measurements, such as in vivo super-resolution and powerful new single-molecule biophysics methods, which facilitate probing of dynamic chromosome processes hitherto impossible. And there are also important advances in the methods of theoretical biophysics which have enabled advances in predictive modeling of this high quality experimental data from molecular and physical biology to generate new understanding of the modes of operation of chromosomes, both in eukaryotic and prokaryotic cells. Here, I discuss these advances, and take stock on the current state of our knowledge of chromosome architecture and speculate where future advances may lead. PMID:27283297

  8. Dean flow fractionation of chromosomes

    Science.gov (United States)

    Hockin, Matt; Sant, Himanshu J.; Capecchi, Mario; Gale, Bruce K.

    2016-03-01

    Efforts to transfer intact mammalian chromosomes between cells have been attempted for more than 50 years with the consistent result being transfer of sub unit length pieces regardless of method. Inertial microfluidics is a new field that has shown much promise in addressing the fractionation of particles in the 2-20 μm size range (with unknown limits) and separations are based upon particles being carried by curving confined flows (within a spiral shaped, often rectangular flow chamber) and migrating to stable "equilibrium" positions of varying distance from a chamber wall depending on the balance of dean and lift forces. We fabricated spiral channels for inertial microfluidic separations using a standard soft lithography process. The concentration of chromosomes, small contaminant DNA and large cell debris in each outlets were evaluated using microscope (60X) and a flow cytometer. Using Dean Flow Fractionation, we were able to focus 4.5 times more chromosomes in outlet 2 compared to outlet 4 where most of the large debris is found. We recover 16% of the chromosomes in outlet #1- 50% in 2, 23% in 3 and 11% in 4. It should be noted that these estimates of recovery do not capture one piece of information- it actually may be that the chromosomes at each outlet are physically different and work needs to be done to verify this potential.

  9. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  10. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/{mu}m) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  11. ON DAMPING COEFFICIENT DUE TO PHASE TRANSFORMATION

    Institute of Scientific and Technical Information of China (English)

    Din-YuHSIEH

    2003-01-01

    The damping coefficient of capillary waves due to the evaporation-condensation process at the interface of the two phases of a fluid is evaluated. To highlight the mechanism of the effect of heat and mass transfer across the interface between regions of liquid and vapor, potential flow of incompressible fluids are assumed. Thus other mechanisms of damping are neglected. To fascilitate the analysis, the method of multiple-scale is employed in the analysis, even though the problem is linear.

  12. The Reduction of Chromosome Number in Meiosis Is Determined by Properties Built into the Chromosomes

    OpenAIRE

    Paliulis, Leocadia V.; Nicklas, R. Bruce

    2000-01-01

    In meiosis I, two chromatids move to each spindle pole. Then, in meiosis II, the two are distributed, one to each future gamete. This requires that meiosis I chromosomes attach to the spindle differently than meiosis II chromosomes and that they regulate chromosome cohesion differently. We investigated whether the information that dictates the division type of the chromosome comes from the whole cell, the spindle, or the chromosome itself. Also, we determined when chromosomes can switch from ...

  13. Epigenetics and autoimmune diseases: the X chromosome-nucleolus nexus.

    Science.gov (United States)

    Brooks, Wesley H; Renaudineau, Yves

    2015-01-01

    Autoimmune diseases occur more often in females, suggesting a key role for the X chromosome. X chromosome inactivation, a major epigenetic feature in female cells that provides dosage compensation of X-linked genes to avoid overexpression, presents special vulnerabilities that can contribute to the disease process. Disruption of X inactivation can result in loss of dosage compensation with expression from previously sequestered genes, imbalance of gene products, and altered endogenous material out of normal epigenetic context. In addition, the human X has significant differences compared to other species and these differences can contribute to the frequency and intensity of the autoimmune disease in humans as well as the types of autoantigens encountered. Here a link is demonstrated between autoimmune diseases, such as systemic lupus erythematosus, and the X chromosome by discussing cases in which typically non-autoimmune disorders complicated with X chromosome abnormalities also present lupus-like symptoms. The discussion is then extended to the reported spatial and temporal associations of the inactive X chromosome with the nucleolus. When frequent episodes of cellular stress occur, the inactive X chromosome may be disrupted and inadvertently become involved in the nucleolar stress response. Development of autoantigens, many of which are at least transiently components of the nucleolus, is then described. Polyamines, which aid in nucleoprotein complex assembly in the nucleolus, increase further during cell stress, and appear to have an important role in the autoimmune disease process. Autoantigenic endogenous material can potentially be stabilized by polyamines. This presents a new paradigm for autoimmune diseases: that many are antigen-driven and the autoantigens originate from altered endogenous material due to episodes of cellular stress that disrupt epigenetic control. This suggests that epigenetics and the X chromosome are important aspects of autoimmune

  14. Dynamics of a condensing liquid film under conjoining/disjoining pressures

    Science.gov (United States)

    Oron, Alexander; Bankoff, S. George

    2001-05-01

    The dynamics of a condensing apolar ultrathin liquid film is studied in the framework of long-wave theory in the cases of both horizontal and slightly tilted solid coated surfaces. When condensation is slow, the film on a horizontal substrate passes through the stages of hole opening driven by the "reverse reservoir effect," hole closing, eventual thickness equilibration and further spatially uniform growth of the condensate. When condensation is faster and the resistance to phase change is lower, secondary droplet(s) may emerge within the hole. During the film evolution the thickness of the microlayer covering the hole remains practically constant due to the "reverse reservoir effect." The total heat flux across the condensate film is found to decrease with the absolute value of the condensation constant. When the solid substrate is tilted, the film dynamics exhibits the formation of multidrop structures and their coarsening along with the stages typical for the horizontal case. The increase of the tilt angle leads to faster transition from dropwise to filmwise condensation and to the increase of the total heat flux through the condensate.

  15. An Experimental Study of the Dropwise Condensation on Physically Processed Surface

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jaeyoung; Chang, Soonheung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Watanabe, N.; Sambuichi, T.; Shiota, D.; Aritomi, M. [Tokyo Institute of Technology, Tokyo (Japan)

    2013-05-15

    Recent research by Kawakubo et al. derived empirical condensation heat transfer correlation suitable for wider range of operating condition in presence of non-condensable gas. However, their proposals of PCCS are focused on plane tube surface. To design better PCCS heat exchanger with high heat transfer coefficient new treatment on condensation surface can be considered in order to maintain dropwise condensation, the heat transfer coefficient of which has an order of magnitude larger than those of film condensation. Advanced research measure dropwise condensation heat transfer coefficient of Au and Cr coated surface based on number of droplet and droplet growth rate. However, coated surface is not desirable in power plant due to its duration of few years. On the other hand, physical processing (micro holes and patterns) on stainless steel and titanium surface is expected to perform better heat transfer, also is durable for the whole reactor lifetime. Since there is no published research about dropwise condensation for physically processed surface on SUS and Ti, the purposes of this research are to measure the condensation heat transfer coefficient and analyze its mechanism of enhanced heat transfer of treated SUS and Ti commonly used to nuclear plant. In the comparison of theoretical equation and experiment, it shows same result that heat transfer coefficient is proportional to maximum droplet diameter power to -0.321. Moreover, in the comparison of bare and processed surface, heat transfer coefficient decreases in processed surface.

  16. CDW-Exciton Condensate Competition and a Condensate Driven Force

    Science.gov (United States)

    Özgün, Ege; Hakioğlu, Tuğrul

    2016-08-01

    We examine the competition between the charge-density wave (CDW) instability and the excitonic condensate (EC) in spatially separated layers of electrons and holes. The CDW and the EC order parameters (OPs), described by two different mechanisms and hence two different transition temperatures TcCDW and TcEC, are self-consistently coupled by a microscopic mean field theory. We discuss the results in our model specifically focusing on the transition-metal dichalcogenides which are considered as the most typical examples of strongly coupled CDW/EC systems with atomic layer separations where the electronic energy scales are large with the critical temperatures in the range TcEC ˜ TcCDW ˜ 100-200 K. An important consequence of this is that the excitonic energy gap, hence the condensed free energy, vary with the layer separation resulting in a new type of force FEC. We discuss the possibility of this force as the possible driver of the structural lattice deformation observed in some TMDCs with a particular attention on the 1T-TiSe2 below 200 K.

  17. Recombination of an intrachromosomal paracentric insertion of chromosome 3

    Energy Technology Data Exchange (ETDEWEB)

    Best, R.G.; Burnett, W.J.; Brock, J.K. [Univ. of South Carolina School of Medicine, Columbia, SC (United States)] [and others

    1994-09-01

    Cytogenetic studies were initiated on a newborn female due to multiple congenital anomalies including microcephaly, clinodactyly, abnormal positioning of hands, left facial palsy, heart defect, sacral dimple, and facial dysmorphic features. Facial features were described as low set rotated ears, nystagmus, and a small, flattened nose. A structural rearrangement of the long arm of chromosome 3 was observed with a complex banding pattern. Study of parental chromosomes revealed a normal male pattern for the father, and an intrachromosomal insertion on the long arm of chromosome 3 for the mother described as 46,XX,dir ins(3)(q21q23q26.2). Further characterization of the proband`s structurally abnormal chromosome 3 revealed a karyotype best described as: 46,XX,rec(3),dupq23{r_arrow}q26.2::q21{r_arrow}q23,dir ins(3)(q21q23q26.2), which is a partial duplication of both the inserted segment as well as the intervening segment between the inserted segment and the insertion site. This would appear to be the result of a three-strand double cross-over within the insertion loop. Molecular cytogenetic studies are presently underway to further elucidate chromosome structure of the proband and her mother.

  18. Sex chromosome aneuploidy in cytogenetic findings of referral patients from south of Iran

    Directory of Open Access Journals (Sweden)

    Najmeh Jouyan

    2012-01-01

    Full Text Available Background: Chromosome abnormality (CA including Sex chromosomes abnormality (SCAs is one of the most important causes of disordered sexual development and infertility. SCAs formed by numerical or structural alteration in X and Y chromosomes, are the most frequently CA encountered at both prenatal diagnosis and at birth. Objective: This study describes cytogenetic findings of cases suspected with CA referred for cytogenetic study. Materials and Methods: Blood samples of 4151 patients referred for cytogenetic analysis were cultured for chromosome preparation. Karyotypes were prepared for all samples and G-Banded chromosomes were analyzed using x100 objective lens. Sex chromosome aneuploidy cases were analyzed and categorized in two groups of Turners and Klinefelter’s syndrome (KFS. Results: Out of 230 (5.54% cases with chromosomally abnormal karyotype, 122 (30% cases suspected of sexual disorder showed SCA including 46% Turner’s syndrome, 46% KFS and the remaining other sex chromosome abnormalities. The frequency of classic and mosaic form of Turner’s syndrome was 33% and 67%, this was 55% and 45% for KFS, respectively. Conclusion: This study shows a relatively high sex chromosome abnormality in this region and provides cytogenetic data to assist clinicians and genetic counselors to determine the priority of requesting cytogenetic study. Differences between results from various reports can be due to different genetic background or ethnicity.

  19. Spontaneous and Stimulated Leukaemogenesis in Mice of the AKR Strain with 38 or 40 Chromosomes

    International Nuclear Information System (INIS)

    At the present time the precise role of chromosome anomalies in the development of cancers is still the subject of controversy in many respects. Some authorities regard chromosome anomalies as the result of the occurrence of tumours, while those subscribing to the theory of somatic mutations regard them as being the first stage thereof. An increased incidence of leukaemias has in fact been observed in people with various chromosome anomalies, such as trisomy 21. The part played by these chromosome anomalies has been studied in the development of spontaneous leukaemias or leukaemias stimulated by exposure to ionizing radiations, as observed in mice of the AKR strain. Mice of this strain normally have 40 chromosomes. The authors were able, some time ago, to isolate a substrain which only has 38 chromosomes (AKR/Tl Ald) due to centromeric fusion of two acrocentric chromosomes. The possible effect of this chromosome change has been studied by comparing, in the two cases, the incidence of lymphoid leukaemias and their period of latency in irradiated and non-irradiated individuals. To stimulate leukaemogenesis the authors adopted the technique of Professor Duplan in which a whole-body dose of 175 R was administered to 30-day-old mice four times at seven-day intervals. The leukaemia diagnosis was established by dissection carried out immediately after death, and in doubtful cases by a histological study. The results obtained are discussed in relation to the theories on the role of chromosome anomalies in carcinogenesis. (author)

  20. Ring chromosome 18 abnormality in acute myelogenous leukemia: the clinical dilemma

    Directory of Open Access Journals (Sweden)

    Malone Adriana K

    2010-07-01

    Full Text Available Abstract The ring chromosome is a circular, structural abnormality composed of either multiple chromosomes or a single chromosome with loss of genetic material at one or both ends. This chromosomal rearrangement is often unstable with frequent recombinations and may be accompanied by either loss or amplification of genetic material1. Considering that ring chromosomes are rare in acute myelogenous leukemia (AML, it is difficult to risk stratify patient prognosis, particularly when the ring chromosome occurs as the sole abnormality. Here we report a case of a ring chromosome 18 abnormality in a patient with newly diagnosed AML with monocytic differentiation. Cytogenetic analysis demonstrated 46, XY, r(18(p11q21 karyotype in 19 of 34 evaluated metaphase cells. The patient received induction chemotherapy and subsequent allogeneic cord blood transplant from a sex-matched donor, and remained in hematologic and cytogenetic remission for 120 days post transplant. Soon after, he developed post transplant lymphoproliferative disorder and died of multi-organ failure. Although r(18 chromosomal abnormalities were not classified in the recent updated evidence-and expert opinion-based recommendations for the diagnosis and management of AML (likely due to the small number of reported cases, the patient was treated as high risk with stem cell transplantation. This was based on the unstable nature of the ring chromosome and the poor outcomes described in the literature of patients with sole ring 18 abnormalities.

  1. Condensation on slippery asymmetric bumps

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Grinthal, Alison; He, Neil; Fox, David; Weaver, James C.; Aizenberg, Joanna

    2016-03-01

    Controlling dropwise condensation is fundamental to water-harvesting systems, desalination, thermal power generation, air conditioning, distillation towers, and numerous other applications. For any of these, it is essential to design surfaces that enable droplets to grow rapidly and to be shed as quickly as possible. However, approaches based on microscale, nanoscale or molecular-scale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach—based on principles derived from Namib desert beetles, cacti, and pitcher plants—that synergistically combines these aspects of condensation and substantially outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle’s bumpy surface geometry in promoting condensation, and using theoretical modelling, we show how to maximize vapour diffusion fluxat the apex of convex millimetric bumps by optimizing the radius of curvature and cross-sectional shape. Integrating this apex geometry with a widening slope, analogous to cactus spines, directly couples facilitated droplet growth with fast directional transport, by creating a free-energy profile that drives the droplet down the slope before its growth rate can decrease. This coupling is further enhanced by a slippery, pitcher-plant-inspired nanocoating that facilitates feedback between coalescence-driven growth and capillary-driven motion on the way down. Bumps that are rationally designed to integrate these mechanisms are able to grow and transport large droplets even against gravity and overcome the effect of an unfavourable temperature gradient. We further observe an unprecedented sixfold-higher exponent of growth rate, faster onset, higher steady-state turnover rate, and a greater volume of water collected compared to other surfaces. We envision that this fundamental understanding and rational design strategy can be

  2. Activated hydrotalcites as solid base catalysts in aldol condensations

    OpenAIRE

    Roelofs, J.C.A.A.

    2002-01-01

    The development of new catalytic materials and routes to replace environmentally unacceptable processes in the fine chemical industry is emerging due to stringent legislation. Replacement of currently applied alkali bases in liquid-phase aldol condensations can result in diminishing of waste water streams, less corrosion and catalyst re-use. The chosen candidate for this is the anionic clay hydrotalcite (HT), which shows promising results after activation. However, why a treated HT is catalyt...

  3. Calculation in Orifice Plate of CEFR Condensate Water Recycling System

    Institute of Scientific and Technical Information of China (English)

    TANG; Yi-min

    2012-01-01

    <正>In order to avoid condensation water pump occurring cavitation due to the flow is too small and affect the normal operation of pump when the startup or shutdown in the unit, low load or accident under empty load operation, recirculation loop should maintain a certain flow, to ensure that the shaft seal heater has enough cooling water, recirculation flow is not less than 20 t/h.

  4. Sex ratio in normal and disomic sperm: Evidence that the extra chromosome 21 preferentially segregates with the Y chromosome

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, D.K.; Millie, E.A.; Hassold, T.J. [Case Western Univ., Cleveland, OH (United States)]|[Univ. Hospitals of Cleveland, OH (United States)] [and others

    1996-11-01

    In humans, deviations from a 1:1 male:female ratio have been identified in both chromosomally normal and trisomic live births: among normal newborns there is a slight excess of males, among trisomy 18 live borns a large excess of females, and among trisomy 21 live borns an excess of males. These differences could arise from differential production of or fertilization by Y- or X-bearing sperm or from selection against male or female conceptions. To examine the proportion of Y- and X- bearing sperm in normal sperm and in sperm disomic for chromosomes 18 or 21, we used three-color FISH (to the X and Y and either chromosome 18 or chromosome 21) to analyze > 300,000 sperm from 24 men. In apparently normal sperm, the sex ratio was nearly 1:1 (148,074 Y-bearing to 148,657 X-bearing sperm), and the value was not affected by the age of the donor. Certain of the donors, however, had significant excesses of Y- or X-bearing sperm. In disomy 18 sperm, there were virtually identical numbers of Y- and X-bearing sperm; thus, the excess of females in trisomy 18 presumably is due to selection against male trisomic conceptions. In contrast, we observed 69 Y-bearing and 44 X-bearing sperm disomic for chromosome 21. This is consistent with previous molecular studies, which have identified an excess of males among paternally derived cases of trisomy 21, and suggests that some of the excess of males among Down syndrome individuals is attributable to a nondisjunctional mechanism in which the extra chromosome 21 preferentially segregates with the Y chromosome. 17 refs., 2 tabs.

  5. Spinor Bose–Einstein condensates

    International Nuclear Information System (INIS)

    An overview of the physics of spinor and dipolar Bose–Einstein condensates (BECs) is given. Mean-field ground states, Bogoliubov spectra, and many-body ground and excited states of spinor BECs are discussed. Properties of spin-polarized dipolar BECs and those of spinor–dipolar BECs are reviewed. Some of the unique features of the vortices in spinor BECs such as fractional vortices and non-Abelian vortices are delineated. The symmetry of the order parameter is classified using group theory, and various topological excitations are investigated based on homotopy theory. Some of the more recent developments in a spinor BEC are discussed.

  6. Quantum tunnelling in condensed media

    CERN Document Server

    Kagan, Yu

    1992-01-01

    The essays in this book deal with of the problem of quantum tunnelling and related behavior of a microscopic or macroscopic system, which interacts strongly with an ""environment"" - this being some form of condensed matter. The ""system"" in question need not be physically distinct from its environment, but could, for example, be one particular degree of freedom on which attention is focussed, as in the case of the Josephson junction studied in several of the papers. This general problem has been studied in many hundreds, if not thousands, of articles in the literature, in contexts as diverse

  7. Dropwise Condensation on Hydrophobic Cylinders

    CERN Document Server

    Park, Kyoo-Chul; Hoang, Michelle; McManus, Brendan; Aizenberg, Joanna

    2016-01-01

    In this work, we studied the effect of the diameter of horizontal hydrophobic cylinders on droplet growth. We postulate that the concentration gradient created by natural convection around a horizontal circular cylinder is related to the droplet growth on the cylinder by condensation. We derive a simple scaling law of droplet growth and compare it with experimental results. The predicted negative exponent of drop diameter (d) as a function of cylinder diameter (D) at different time points is similar to the general trend of experimental data. Further, this effect of cylinder diameter on droplet growth is observed to be stronger than the supersaturation conditions created by different surface temperatures.

  8. Velocity condensation for magnetotactic bacteria

    CERN Document Server

    Rupprecht, Jean-Francois; Bocquet, Lydéric

    2015-01-01

    Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g. active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that L\\'evy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior.

  9. Velocity Condensation for Magnetotactic Bacteria.

    Science.gov (United States)

    Rupprecht, Jean-François; Waisbord, Nicolas; Ybert, Christophe; Cottin-Bizonne, Cécile; Bocquet, Lydéric

    2016-04-22

    Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g., active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that Lévy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior. PMID:27152825

  10. Human interphase chromosomes: a review of available molecular cytogenetic technologies

    Directory of Open Access Journals (Sweden)

    Yurov Yuri B

    2010-01-01

    Full Text Available Abstract Human karyotype is usually studied by classical cytogenetic (banding techniques. To perform it, one has to obtain metaphase chromosomes of mitotic cells. This leads to the impossibility of analyzing all the cell types, to moderate cell scoring, and to the extrapolation of cytogenetic data retrieved from a couple of tens of mitotic cells to the whole organism, suggesting that all the remaining cells possess these genomes. However, this is far from being the case inasmuch as chromosome abnormalities can occur in any cell along ontogeny. Since somatic cells of eukaryotes are more likely to be in interphase, the solution of the problem concerning studying postmitotic cells and larger cell populations is interphase cytogenetics, which has become more or less applicable for specific biomedical tasks due to achievements in molecular cytogenetics (i.e. developments of fluorescence in situ hybridization -- FISH, and multicolor banding -- MCB. Numerous interphase molecular cytogenetic approaches are restricted to studying specific genomic loci (regions being, however, useful for identification of chromosome abnormalities (aneuploidy, polyploidy, deletions, inversions, duplications, translocations. Moreover, these techniques are the unique possibility to establish biological role and patterns of nuclear genome organization at suprachromosomal level in a given cell. Here, it is to note that this issue is incompletely worked out due to technical limitations. Nonetheless, a number of state-of-the-art molecular cytogenetic techniques (i.e multicolor interphase FISH or interpahase chromosome-specific MCB allow visualization of interphase chromosomes in their integrity at molecular resolutions. Thus, regardless numerous difficulties encountered during studying human interphase chromosomes, molecular cytogenetics does provide for high-resolution single-cell analysis of genome organization, structure and behavior at all stages of cell cycle.

  11. Chromosomal abnormalities in spontaneous abortion after assisted reproductive treatment

    Directory of Open Access Journals (Sweden)

    Kim You

    2010-11-01

    Full Text Available Abstract Background We evaluated cytogenetic results occurring with first trimester pregnancy loss, and assessed the type and frequency of chromosomal abnormalities after assisted reproductive treatment (ART and compared them with a control group. We also compared the rate of chromosomal abnormalities according to infertility causes in ICSI group. Methods A retrospective cohort analysis was made of all patients who were referred to the Genetics Laboratory of Fertility Center of CHA Gangnam Medical Center from 2005 to 2009 because of clinical abortion with a subsequent dilation and evacuation (D&E performed, and patients were grouped by type of conception as follows: conventional IVF (in vitro fertilization (n = 114, ICSI (intracytoplasmic sperm injection (n = 140, and control (natural conception or intrauterine insemination [IUI] (n = 128. Statistical analysis was performed using SPSS software. Results A total 406 specimens were referred to laboratory, ten abortuses were excluded, and in 14 cases, we did not get any spontaneous metaphase, chromosomal constitutions of 382 specimens were successfully obtained with conventional cytogenetic methods. Overall, 52.62% of the miscarriages were found to be cytogenetically abnormal among all patients, the frequency was 48.4% in the control group, 54.3% of miscarriages after ICSI and 55.3% after conventional IVF (p = 0.503. The most prevalent abnormalities were autosomal trisomy, however, nine (11.69% sex chromosome aneuploidy were noted in the ICSI group vs. four (6.45% and two (3.23% cases in the conventional IVF group and control group. We compared chromosomal abnormalities of miscarriages after ICSI according to infertility factor. 55.71% underwent ICSI due to male factors, 44.29% due to non-male factors. ICSI group having male factors showed significantly higher risk of chromosomal abnormalities than ICSI group having non-male factors (65.8% vs. 34.2%, p = 0.009, odds ratio = 1.529, 95% CI = 1

  12. Contribution of cloud condensate to surface rainfall process

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yushu; CUI Xiaopeng; LI Xiaofan

    2006-01-01

    Contribution of cloud condensate to surface rainfall processes is investigated in a life span of tropical convection based on hourly data from a two-dimensional cloud resolving simulation. The model is forced by the large-scale vertical velocity, zonal wind and horizontal advections obtained from tropical ocean global atmosphere coupled ocean-atmosphere response experiment (TOGA COARE). The results show that during the genesis, development, and decay of tropical convection, calculations with water vapor overestimate surface rain rate, and cloud condensate plays an important role in correcting overestimation in surface rain rates. The analysis is carried out in deep convective clouds and anvil clouds during the development of tropical convection. The surface rain rates calculated with water vapor in deep convective clouds and anvil clouds have similar magnitudes, the large surface rain rate appears in deep convective clouds due to the consumption of water hydrorneteors whereas the small surface rain rate occurs in anvil clouds because of the gain of ice hydrometeors. Further analysis of the grid data shows that the surface rain rates calculated with water vapor and with cloud condensate are negatively correlated with the correlation coefficient of - 0.85, and the surface rain rate calculated with cloud condensate is mainly contributed to the water hydrometeors in the tropical deep convective regime.

  13. Drying of pulverized material with heated condensible vapor

    Science.gov (United States)

    Carlson, Larry W.

    1986-01-01

    Apparatus for drying pulverized material utilizes a high enthalpy condensable vapor such as steam for removing moisture from the individual particles of the pulverized material. The initially wet particulate material is tangentially delivered by a carrier vapor flow to an upper portion of a generally vertical cylindrical separation drum. The lateral wall of the separation drum is provided with a plurality of flow guides for directing the vapor tangentially therein in the direction of particulate material flow. Positioned concentrically within the separation drum and along the longitudinal axis thereof is a water-cooled condensation cylinder which is provided with a plurality of collection plates, or fins, on the outer lateral surface thereof. The cooled collection fins are aligned counter to the flow of the pulverized material and high enthalpy vapor mixture to maximize water vapor condensation thereon. The condensed liquid which includes moisture removed from the pulverized material then flows downward along the outer surface of the coolant cylinder and is collected and removed. The particles travel in a shallow helix due to respective centrifugal and vertical acceleration forces applied thereto. The individual particles of the pulverized material are directed outwardly by the vortex flow where they contact the inner cylindrical surface of the separation drum and are then deposited at the bottom thereof for easy collection and removal. The pulverized material drying apparatus is particularly adapted for drying coal fines and facilitates the recovery of the pulverized coal.

  14. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; MATSHUDA, Yoichi; 秀之, 田辺

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7–10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  15. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; Matsuda, Yoichi

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7Y10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  16. The physics of exciton-polariton condensates

    CERN Document Server

    Lagoudakis, Konstantinos

    2013-01-01

    In 2006 researchers created the first polariton Bose-Einstein condensate at 19K in the solid state. Being inherently open quantum systems, polariton condensates open a window into the unpredictable world of physics beyond the “fifth state of matter”: the limited lifetime of polaritons renders polariton condensates out-of-equilibrium and provides a fertile test-bed for non-equilibrium physics. This book presents an experimental investigation into exciting features arising from this non-equilibrium behavior. Through careful experimentation, the author demonstrates the ability of polaritons to synchronize and create a single energy delocalized condensate. Under certain disorder and excitation conditions the complete opposite case of coexisting spatially overlapping condensates may be observed. The author provides the first demonstration of quantized vortices in polariton condensates and the first observation of fractional vortices with full phase and amplitude characterization. Finally, this book investigate...

  17. Bio-oil fractionation and condensation

    Science.gov (United States)

    Brown, Robert C; Jones, Samuel T; Pollard, Anthony

    2013-07-02

    A method of fractionating bio-oil vapors which involves providing bio-oil vapors comprising bio-oil constituents is described. The bio-oil vapors are cooled in a first stage which comprises a condenser having passages for the bio-oil separated by a heat conducting wall from passages for a coolant. The coolant in the condenser of the first stage is maintained at a substantially constant temperature, set at a temperature in the range of 75 to 100.degree. C., to condense a first liquid fraction of liquefied bio-oil constituents in the condenser of the first stage. The first liquid fraction of liquified bio-oil constituents from the condenser in the first stage is collected. Also described are steps for subsequently recovering further liquid fractions of liquefied bio-oil constituents. Particular compositions of bio-oil condensation products are also described.

  18. Condensing Heat Recovery of Centrifugal Chiller

    Institute of Scientific and Technical Information of China (English)

    GONG Guang-cai; JIAO Jun-jun; WANG Li-ping; ZENG Wei

    2009-01-01

    To a kind of centrifugal water chiUer with R22 and about 1745 kW of cooling capacity.a heat exchanger was added between the outlet of compressor and original condenser to get part of or all the condensing heat.Condensing heat can be recovered by compound condensing method,which adopts air-cooling model+wa-ter-cooling model or water-cooling model+water-cooling model at the condensing side of the system.By exergy analysis and experiment research on compound condensing heat recovery of centrifugal chiller,the results are ob-tained that the capability of the whole system increases,the energy efficiency ratio (EER) becomes 3.2~5.0 from 2.2~3.4, which implies the EER increases about 1.0~1.5,the exergy efficiency increases about 10%,and the chiller runs more stably after reformation.

  19. Dynamics of vertebrate sex chromosome evolution: from equal size to giants and dwarfs.

    Science.gov (United States)

    Schartl, Manfred; Schmid, Michael; Nanda, Indrajit

    2016-06-01

    The Y and W chromosomes of mammals and birds are known to be small because most of their genetic content degenerated and were lost due to absence of recombination with the X or Z, respectively. Thus, a picture has emerged of ever-shrinking Ys and Ws that may finally even fade into disappearance. We review here the large amount of literature on sex chromosomes in vertebrate species and find by taking a closer look, particularly at the sex chromosomes of fishes, amphibians and reptiles where several groups have evolutionary younger chromosomes than those of mammals and birds, that the perception of sex chromosomes being doomed to size reduction is incomplete. Here, sex-determining mechanisms show a high turnover and new sex chromosomes appear repeatedly. In many species, Ys and Ws are larger than their X and Z counterparts. This brings up intriguing perspectives regarding the evolutionary dynamics of sex chromosomes. It can be concluded that, due to accumulation of repetitive DNA and transposons, the Y and W chromosomes can increase in size during the initial phase of their differentiation. PMID:26715206

  20. Dual-species Bose-Einstein condensate of Rb87 and Cs133

    Science.gov (United States)

    McCarron, D. J.; Cho, H. W.; Jenkin, D. L.; Köppinger, M. P.; Cornish, S. L.

    2011-07-01

    We report the formation of a dual-species Bose-Einstein condensate of Rb87 and Cs133 in the same trapping potential. Our method exploits the efficient sympathetic cooling of Cs133 via elastic collisions with Rb87, initially in a magnetic quadrupole trap and subsequently in a levitated optical trap. The two condensates each contain up to 2×104 atoms and exhibit a striking phase separation, revealing the mixture to be immiscible due to strong repulsive interspecies interactions. Sacrificing all the Rb87 during the cooling, we create single-species Cs133 condensates of up to 6×104 atoms.

  1. Spin Polarized versus Chiral Condensate in Quark Matter at Finite Temperature and Density

    CERN Document Server

    Matsuoka, H; da Providencia, J; Providencia, C; Yamamura, M; Bohr, H

    2016-01-01

    It is shown that the spin polarized condensate appears in quark matter at high baryon density and low temperature due to the tensor-type four-point interaction in the Nambu-Jona-Lasinio-type model as a low energy effective theory of quantum chromodynamics. It is indicated within this low energy effective model that the chiral symmetry is broken again by the spin polarized condensate as increasing the quark number density, while the chiral symmetry restoration occurs in which the chiral condensate disappears at a certain density.

  2. Electron beam heating effects during environmental scanning electron microscopy imaging of water condensation on superhydrophobic surfaces

    Science.gov (United States)

    Rykaczewski, K.; Scott, J. H. J.; Fedorov, A. G.

    2011-02-01

    Superhydrophobic surfaces (SHSs) show promise as promoters of dropwise condensation. Droplets with diameters below ˜10 μm account for the majority of the heat transferred during dropwise condensation but their growth dynamics on SHS have not been systematically studied. Due to the complex topography of the surface environmental scanning electron microscopy is the preferred method for observing the growth dynamics of droplets in this size regime. By studying electron beam heating effects on condensed water droplets we establish a magnification limit below which the heating effects are negligible and use this insight to study the mechanism of individual drop growth.

  3. Stability of magnetic condensation and mass generation for confinement in SU(2) Yang-Mills theory

    CERN Document Server

    Kondo, Kei-Ichi

    2013-01-01

    In the framework of the functional renormalization group, we reexamine the stability of the Yang-Mills vacuum with a chromomagnetic condensation. We show that the Nielsen-Olesen instability of the Savvidy vacuum with a homogeneous chromomagnetic condensation disappears in the $SU(2)$ Yang-Mills theory. As a physical mechanism for maintaining the stability even for the small infrared cutoff, we argue that dynamical gluon mass generation occurs due to a BRST-invariant vacuum condensate of mass dimension-two, which is related to two-gluon bound states identified with glueballs. These results support the dual superconductor picture for quark confinement.

  4. Depletion of superfluidity in a disordered non-equilibrium quantum condensate

    Energy Technology Data Exchange (ETDEWEB)

    Janot, Alexander; Rosenow, Bernd [Institut fuer Theoretische Physik, Universitaet Leipzig, 04009 Leipzig (Germany); Hyart, Timo [Institute of Physics, Leiden University, Niels Bohrweg 2, 2333 CA Leiden (Netherlands); Eastham, Paul [School of Physics, Trinity College, Dublin 2 (Ireland)

    2013-07-01

    Observations of quantum coherence in driven systems, e.g. polariton condensates, have strongly stimulated experimental as well as theoretical efforts during the last decade. We analyze the superfluid stiffness of a non-equilibrium quantum-condensate in a disordered environment taking gain and loss of particles into account. To this end a modified effective Gross-Pitaevskii equation is employed. We find that the disorder-driven depletion of superfluidity is strongly enhanced due to the gain-loss mechanism. It turns out that the condensate remains stiff at finite length scales only.

  5. Quantum threshold for optomechanical self-structuring in a Bose-Einstein condensate.

    Science.gov (United States)

    Robb, G R M; Tesio, E; Oppo, G-L; Firth, W J; Ackemann, T; Bonifacio, R

    2015-05-01

    Theoretical analysis of the optomechanics of degenerate bosonic atoms with a single feedback mirror shows that self-structuring occurs only above an input threshold that is quantum mechanical in origin. This threshold also implies a lower limit to the size (period) of patterns that can be produced in a condensate for a given pump intensity. These thresholds are interpreted as due to the quantum rigidity of Bose-Einstein condensates, which has no classical counterpart. Above the threshold, the condensate self-organizes into an ordered supersolid state with a spatial period self-selected by optical diffraction. PMID:25978236

  6. A condensed global photochemical mechanism for two-dimensional atmospheric models

    Energy Technology Data Exchange (ETDEWEB)

    Tamaresis, J.; Kinnison, D.E.; Wuebbles, D.J.

    1991-01-01

    A condensed chemical mechanism that represents the reactions of organic compounds in the atmosphere is developed and tested using a one-dimensional model. Due to the differences between the full and condensed mechanisms, the reduced version cannot be considered an accurate predictor of globally important trace species concentrations. The condensed mechanism must be improved before it can be used with confidence in two-dimensional models. Appendix contains both full and reduced mechanisms of photolysis and thermal reactions as well as species profile comparisons. 3 refs., 8 figs.

  7. Active condensation of water by plants

    OpenAIRE

    Prokhorov Alexey Anatolievich

    2013-01-01

    This paper is devoted to some peculiarities of water condensation on the surface of plants . Arguments in support of the hypothesis that in decreasing temperature of leaves and shoots below the dew point, the plant can actively condense moisture from the air, increasing the duration of dewfall are presented. Evening dewfall on plant surfaces begins before starting the formation of fog. Morning condensation continues for some time after the air temperature exceeds the dew point . The phenomen...

  8. Droplet condensation on polymer surfaces: a review

    OpenAIRE

    UÇAR, İkrime Orkan; ERBİL, Hüsnü Yıldırım

    2013-01-01

    Dropwise condensation on substrates is an important topic of interest because it plays a crucial role in many scientific applications such as heat transfer, water harvesting from the humid atmosphere, and polymer templating. We focused on droplet condensation on polymer surfaces and briefly summarized the drop condensation studies reported in the last 2 decades and their potential applications. The main topics discussed in this review are water harvesting from dew using radiative ...

  9. Structure of Nonlocal Vacuum Condensate of Quarks

    Institute of Scientific and Technical Information of China (English)

    周丽娟; 马维兴

    2003-01-01

    The Dyson-Schwinger formalism is used to derive a fully dressed quark propagator. By use of the derived form of the quark propagator, the structure of non-local quark vacuum condensate is studied, and the values of local quark vacuum condensate as well as quark gluon mixed condensate are calculated. The theoretical predictions are in good agreement with the empirical one used commonly in the literature.

  10. THE STABILITY OF VAPOR CONDENSATION EQUILIBRIUM

    OpenAIRE

    SHIMIN ZHANG

    2005-01-01

    The system must get across an energy peak of unstable equilibrium during the condensation of pure vapor; as the supersaturated extent of vapor increases and the temperature decreases, the energy peak shortens and vapor condensation becomes easier. The system must get across an energy peak of unstable equilibrium first, and then get into an energy valley of stable equilibrium during the condensation of impure vapor; as the partial pressure of vapor decreases, the energy peak becomes taller, th...

  11. Non nodal condensation of eigenvalue problems

    OpenAIRE

    Mackens, Wolfgang; Voss, Heinrich

    1997-01-01

    We generalize the Guyan condensation of large symmetric eigenvalue problems to allow general degrees of freedom to be master variables. On one hand useful information from other condensation methods (such as Component Mode Synthesis) thus can be incorporated into the method. On the other hand this opens the way to iterative refinement of eigenvector approximations. Convergence of such a procedure follows from the result, that one step of (static) condensation is equivalent to one step of inve...

  12. Bose-Einstein condensation of 84Sr.

    Science.gov (United States)

    Martinez de Escobar, Y N; Mickelson, P G; Yan, M; DeSalvo, B J; Nagel, S B; Killian, T C

    2009-11-13

    We report Bose-Einstein condensation of (84)Sr in an optical dipole trap. Efficient laser cooling on the narrow intercombination line and an ideal s-wave scattering length allow the creation of large condensates (N(0) approximately 3 x 10(5)) even though the natural abundance of this isotope is only 0.6%. Condensation is heralded by the emergence of a low-velocity component in time-of-flight images. PMID:20365965

  13. Bose-Einstein Condensation of 84-Sr

    OpenAIRE

    de Escobar, Y. N. Martinez; Mickelson, P. G.; Yan, M; DeSalvo, B. J.; Nagel, S. B.; Killian, T. C.

    2009-01-01

    We report Bose-Einstein condensation of 84-Sr in an optical dipole trap. Efficient laser cooling on the narrow intercombination line and an ideal s-wave scattering length allow creation of large condensates (N0 ~ 3x10^5) even though the natural abundance of this isotope is only 0.6%. Condensation is heralded by the emergence of a low-velocity component in time-of-flight images.

  14. Ultra-low threshold polariton condensation

    CERN Document Server

    Steger, Mark; Alberi, Kirstin; Mascarenhas, Angelo; Snoke, David W; Pfeiffer, Loren N; West, Ken

    2016-01-01

    We demonstrate condensation of microcavity polaritons with a very sharp threshold occuring at two orders of magnitude lower pump intensity than previous demonstrations of condensation. The long cavity-lifetime and trapping and pumping geometries are crucial to the realization of this low threshold. Polariton condensation, or "polariton lasing" has long been proposed as a promising source of coherent light at lower threshold than traditional lasing, and these results suggest methods to bring this threshold even lower.

  15. Dual quark condensate and dressed Polyakov loops

    OpenAIRE

    Bilgici, Erek; Bruckmann, Falk; Gattringer, Christof; Hagen, Christian

    2008-01-01

    We construct a new order parameter for finite temperature QCD by considering the quark condensate for U(1)-valued temporal boundary conditions for the fermions. Fourier transformation with respect to the boundary condition defines the dual condensate. This quantity corresponds to an equivalence class of Polyakov loops, thereby being an order parameter for the center symmetry. We explore the duality relation between the quark condensate and these dressed Polyakov loops numerically, using quenc...

  16. Reference Temperature for Evaluating Physical Properties of Condensate Film in the case of Free-Convection Laminar Film Condensation

    OpenAIRE

    新里, 寛英; 李, 鍾鵬; 藤井, 哲

    1992-01-01

    The boundary layer equations for free-convection laminar film condensation of pure vapors of water, ethanol and propane on a vertical surface are numerically solved for the cases of constant properties, variable viscosity and variable relevant physical properties. The conclusions are as follows: (1) The ratio of the heat flux at the vapor-liquid interface to that at the cooling surface is expressed by [numerical formula] (2) The correction for Nusselt's equation due to the thermal convection ...

  17. Condensation and Evaporation of Interstellar Clouds in Chemodynamical Models of Galaxies

    CERN Document Server

    Köppen, J; Hensler, G; Theis, Ch.

    1997-01-01

    The network of interactions between hot gas, cool clouds, massive stars, and stellar remnants used in the chemodynamical modeling of the interstellar medium is investigated for the types of its solutions. In a physically consistent formulation for the energy transfer during condensation, oscillations due to a cyclic switching between condensation and evaporation never occur. A closed-box system evolves in a hierarchy of equilibria: thermal balance in the cloud gas, star-formation self-regulated due to heating of the clouds by massive stars, and the balance of condensation and evaporation. Except for an initial transitory phase, the evolution of the metallicity follows that of the Simple Model quite closely. For galaxies with a high initial density, or if the condensation rate is low, the metals produced by the stars may remain stored in the hot gas phase even in evolved systems with low gas fractions.

  18. Spin-polarized versus chiral condensate in quark matter at finite temperature and density

    DEFF Research Database (Denmark)

    Matsuoka, Hiroaki; Tsue, Yasuhiko; da Providencia, Joao;

    2016-01-01

    It is shown that the spin-polarized condensate appears in quark matter at high baryon density and low temperature due to the tensor-type four-point interaction in the Nambu-Jona-Lasiniotype model as a low-energy effective theory of quantum chromodynamics. It is indicated within this low-energy ef......It is shown that the spin-polarized condensate appears in quark matter at high baryon density and low temperature due to the tensor-type four-point interaction in the Nambu-Jona-Lasiniotype model as a low-energy effective theory of quantum chromodynamics. It is indicated within this low......-energy effective model that the chiral symmetry is broken again by the spin-polarized condensate on increasing the quark number density, while chiral symmetry restoration occurs, in which the chiral condensate disappears at a certain density....

  19. Acoustic radiation from vortex–barrier interaction in atomic Bose–Einstein condensate

    International Nuclear Information System (INIS)

    We examine the dynamics of a vortex dipole in the Bose–Einstein condensates of trapped dilute atomic gases at zero temperature in the presence of a Gaussian barrier potential. The density anisotropy induced by the barrier enhances the acoustic radiation from the vortex dipole. This is due to the deviation of the condensate density from the equipotential curves and variation in the curvature of the vortex dipole trajectory. Due to the acoustic radiation, the vortex dipole dissipates energy and spirals towards the edge of the condensate. As a result, we observe an increase in the vortex–antivortex annihilation events. To examine the effect of the Gaussian barrier, we estimate the correction to the Thomas–Fermi condensate density using the perturbation expansion method and the results are in very good agreement with the numerical results. (paper)

  20. An experimental and numerical study into turbulent condensing steam jets in air

    Science.gov (United States)

    Oerlemans, S.; Badie, R.; Van Dongen, M. E. H.

    Temperatures, velocities, and droplet sizes are measured in turbulent condensing steam jets produced by a facial sauna, for varying nozzle diameters and varying initial velocities (Re=3,600-9,200). The release of latent heat due to droplet condensation causes the temperature in the two-phase jet to be significantly higher than in a single-phase jet. At some distance from the nozzle, droplets reach a maximum size and start to evaporate again, which results in a change in sign of latent heat release. The distance of maximum size is determined from droplet size measurements. The experimental results are compared with semi-analytical expressions and with a fully coupled numerical model of the turbulent condensing steam jet. The increase in centreline temperature due to droplet condensation is successfully predicted.

  1. Assessment of Modified Wall Condensation Models of MARS-KS and SPACE Codes using Reflux Condensation Test

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Won; Cheong, Ae Ju; Suh, Duk SUH [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    The wall condensation models of MARS-KS and SPACE codes adopt the Colburn-Hougen diffusion method to solve for the liquid-gas interface temperature in the presence of noncondensable (NC) gases. Recent studies reported that there was an error in the vapor mass flux term when the models were implemented in the codes. This error causes the codes to underestimate the steam condensation rate. This tendency becomes more noticeable with the increase in the mole fraction of NC gases. In this study, we assess the modified condensation model of MARS-KS and SPACE codes. The calculation results of modified version of the codes (MARS-KS 1.3r1 and SPACE 2.16r1) are compared to those of the original version (MARS-KS 1.3 and SPACE 2.14) and the experimental data. The modified model predicts higher heat fluxes and HTCs than the original model due to the increase in the steam condensation rate. At relatively high air mass fraction, the modified model increases the discrepancy between the measured data and calculated values.

  2. Condensation induced water hammer safety

    Energy Technology Data Exchange (ETDEWEB)

    Gintner, M.A.

    1997-03-10

    Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer.

  3. Muonic Chemistry in Condensed Matter

    CERN Multimedia

    2002-01-01

    When polarized muons (@m|+) stop in condensed matter, muonic atoms are formed in the final part of their range, and direct measurements of the @m|+-spin polarization are possible via the asymmetric decay into positrons. The hyperfine interaction determines the characteristic precession frequencies of the @m|+ spin in muonium, @w(Mu). Such frequencies can be altered by the interactions of the muonium's electron spin with the surrounding medium. The measurement of @w(Mu) in a condensed system is known often to provide unique information regarding the system. \\\\ \\\\ In particular, the use of muonium atoms as a light isotope of the simple reactive radical H|0 allows the investigation of fast reactions of radicals over a typical time scale 10|-|9~@$<$~t~@$<$~10|-|5~sec, which is determined by the instrumental resolution at one end and by the @m|+ lifetime at the other. \\\\ \\\\ In biological macromolecules transient radicals, such as the constituents of DNA itself, exist on a time scale of sub-microseconds, acco...

  4. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished...

  5. CHROMOSOMAL MULTIPLICITY IN BURKHOLDERIA CEPACIA

    Science.gov (United States)

    We have used CHEF gel electrophoresis to screen preparations of large DNA from different Burkholderia cepacia isolates for the presence of DNA species corresponding to the linearized forms of the three chromosomes of 3.4,2.5, and 0.9 Mb identified in B. cepacia strain 17616. DNA ...

  6. Chromosomal disorders and male infertility

    Institute of Scientific and Technical Information of China (English)

    Gary L Harton; Helen G Tempest

    2012-01-01

    infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family.Despite this,the molecular and genetic factors underlying the cause of infertility remain largely undiscovered.Nevertheless,more and more genetic factors associated with infertility are being identified.This review will focus on our current understanding of the chromosomal basis of male infertility specifically:chromosomal aneuploidy,structural and numerical karyotype abnormalities and Y chromosomal microdeletions.Chromosomal aneuploidy is the leading cause of pregnancy loss and developmental disabilities in humans.Aneuploidy is predominantly maternal in origin,but concerns have been raised regarding the safety of intracytoplasmic sperm injection as infertile men have significantly higher levels of sperm aneuploidy compared to their fertile counterparts.Males with numerical or structural karyotype abnormalities are also at an increased risk of producing aneuploid sperm.Our current understanding of how sperm aneuploidy translates to embryo aneuploidy will be reviewed,as well as the application of preimplantation genetic diagnosis (PGD) in such cases.Clinical recommendations where possible will be made,as well as discussion of the use of emerging array technology in PGD and its potential applications in male infertility.

  7. Advances in modelling of condensation phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.S.; Zaltsgendler, E. [Ontario Hydro Nuclear, Toronto (Canada); Hanna, B. [Atomic Energy of Canada Limited, Pinawa, Manitoba (Canada)

    1997-07-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described.

  8. Enhanced condensation heat transfer with wettability patterning

    Science.gov (United States)

    Sinha Mahapatra, Pallab; Ghosh, Aritra; Ganguly, Ranjan; Megaridis, Constantine

    2015-11-01

    Condensation of water vapor on metal surfaces is useful for many engineering applications. A facile and scalable method is proposed for removing condensate from a vertical plate during dropwise condensation (DWC) in the presence of non-condensable gases (NCG). We use wettability-patterned superhydrophilic tracks (filmwise condensing domains) on a mirror-finish (hydrophilic) aluminum surface that promotes DWC. Tapered, horizontal ``collection'' tracks are laid to create a Laplace pressure driven flow, which collects condensate from the mirror-finish domains and sends it to vertical ``drainage tracks'' for gravity-induced shedding. An optimal design is achieved by changing the fractional area of superhydrophilic tracks with respect to the overall plate surface, and augmenting capillary-driven condensate-drainage by adjusting the track spatial layout. The design facilitates pump-less condensate drainage and enhances DWC heat transfer on the mirror-finish regions. The study highlights the relative influences of the promoting and retarding effects of dropwise and filmwise condensation zones on the overall heat transfer improvement on the substrate. The study demonstrated ~ 34% heat transfer improvement on Aluminum surface for the optimized design.

  9. Radiotherapeutical chromosomal aberrations in laryngeal cancer patients

    Directory of Open Access Journals (Sweden)

    Stošić-Divjak Svetlana L.

    2009-01-01

    Full Text Available Introduction. The authors present the results of cytogenetic analysis of 21 patients with laryngeal carcinomas diagnosed and treated in the period 1995-2000 at the Institute of Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia and Clinical Center of Novi Sad. Material and methods. The patients were specially monitored and the material was analyzed at the Institute of Human Genetics of the School of Medicine in Belgrade as well as in the Laboratory for Radiological Protection of the Institute of Occupational and Radiological Health 'Dr Dragomir Karajovic' in Belgrade. Results. The incidence of chromosomal aberrations and incidence of exchange of material between sister chromatids were observed in the preparation of the metaphasic lymphocyte chromosomes of the peripheral blood obtained in the culture. Structural aberrations were found on the chromosomes in the form of breakups, rings, translocations and dicentrics as early as after a single exposure of patients to tumor radiation dose of 2 Gy in the field sized 5x7. Out of the total number of 35 cultivated blood samples obtained from 13 patients, 21 were successfully cultivated and they were proved to contain chromosomal aberrations. Some of the peripheral blood samples failed to show cell growth in vitro due to the lethal cell damages in vivo. Discussion.. We have consluded that the number of structural aberrations cannot be used as a biological measure of the absorbed ionizing radiation dose. The presence of aberrations per se is indicative of the mutagenic effect of the ionizing radiation, which was also confirmed in our series on the original model by cultivation of the peripheral blood lymphocytes in the culture of the cells of the volunteer donors upon in vitro radiation. Using the method of bromdeoxyuridylreductase, the increased incidence of SCE as a mutagenic effect was registered. Conclusion. It has been concluded that the increase of absorbed radiation dose in

  10. Multicolor spectral karyotyping of human chromosomes.

    Science.gov (United States)

    Schröck, E; du Manoir, S; Veldman, T; Schoell, B; Wienberg, J; Ferguson-Smith, M A; Ning, Y; Ledbetter, D H; Bar-Am, I; Soenksen, D; Garini, Y; Ried, T

    1996-07-26

    The simultaneous and unequivocal discernment of all human chromosomes in different colors would be of significant clinical and biologic importance. Whole-genome scanning by spectral karyotyping allowed instantaneous visualization of defined emission spectra for each human chromosome after fluorescence in situ hybridization. By means of computer separation (classification) of spectra, spectrally overlapping chromosome-specific DNA probes could be resolved, and all human chromosomes were simultaneously identified. PMID:8662537

  11. Response of Cloud Condensation Nuclei (> 50 nm) to changes in ion-nucleation

    OpenAIRE

    Svensmark, Henrik; Enghoff, Martin B.; Pedersen, Jens Olaf Pepke

    2013-01-01

    In experiments where ultraviolet light produces aerosols from trace amounts of ozone, sulphur dioxide, and water vapour, the number of additional small particles produced by ionization by gamma sources all grow up to diameters larger than 50 nm, appropriate for cloud condensation nuclei. This result contradicts both ion-free control experiments and also theoretical models that predict a decline in the response of larger particles due to an insufficiency of condensable gases (which leads to sl...

  12. Development of the Prediction System of Condensation Based on Wireless Communications

    OpenAIRE

    Shin-Hyeong Choi

    2013-01-01

    Due to advances in microelectromechanical system (MEMS), many smart sensors have been developed. A large number of sensors build a wireless sensor network and can communicate with each other. Wireless sensor networks help monitor objects in our environment, and many researches about this technology are in progress. Condensation is a phenomenon that water vapor contained in the air condenses and makes water droplets. This is caused by the complex action of a variety of factors, including the t...

  13. Improvement of the technology of the gas treatment by the condensation method

    OpenAIRE

    Летюк, Євген Олександрович

    2014-01-01

    Natural gas treatment for transport using the condensation method is considered in the paper. The main objective of the study is to examine the possibilities of decreasing the amount of low-pressure gases, produced when reducing hydrocarbon condensate, separated from natural gas, to the standard conditions. Decreasing the amount of these gases becomes possible due to introducing a portion of the treated natural gas in a gas-liquid flow before the final stage separator in the gas treatment pla...

  14. Superfluid properties of a Bose-Einstein condensate in an optical lattice confined in a cavity

    OpenAIRE

    Bhattacherjee, A. B.

    2007-01-01

    We study the effect of a one dimensional optical lattice in a cavity field with quantum properties on the superfluid dynamics of a Bose-Einstein condensate(BEC). In the cavity the influence of atomic backaction and the external driving pump become important and strongly modify the optical potential. Due to the strong coupling between the condensate wavefunction and the cavity modes, the cavity light field develops a band structure. This study reveals that the pump and the cavity emerges as a ...

  15. External Water Condensation and Angular Solar Absorptance : Theoretical Analysis and Practical Experience of Modern Windows

    OpenAIRE

    Werner, Anna

    2007-01-01

    Part I of this thesis is a theoretical background to parts II and III. Part II treats the phenomenon of decreased visibility through a glazing due to external water condensation, dew, on the external surface. Some simulations are presented where it is shown that under certain circumstances condensation can be expected. A combination of coatings on the external surface is suggested to overcome the problem of external condesation. It consists of both a coating which decreases the emissivity of ...

  16. Coupling of pion condensate, chiral condensate and Polyakov loop in an extended NJL model

    OpenAIRE

    Zhang, Zhao; Liu, Yu-Xin

    2006-01-01

    The Nambu Jona-Lasinio model with a Polyakov loop is extended to finite isospin chemical potential case, which is characterized by simultaneous coupling of pion condensate, chiral condensate and Polyakov loop. The pion condensate, chiral condensate and the Polyakov loop as functions of temperature and isospin chemical potential are investigated by minimizing the thermodynamic potential of the system. The resulting $(T,\\mu_I)$ phase diagram is studied with emphasis on the critical point and Po...

  17. A Comprehensive Model of Electric-Field-Enhanced Jumping-Droplet Condensation on Superhydrophobic Surfaces.

    Science.gov (United States)

    Birbarah, Patrick; Li, Zhaoer; Pauls, Alexander; Miljkovic, Nenad

    2015-07-21

    Superhydrophobic micro/nanostructured surfaces for dropwise condensation have recently received significant attention due to their potential to enhance heat transfer performance by shedding positively charged water droplets via coalescence-induced droplet jumping at length scales below the capillary length and allowing the use of external electric fields to enhance droplet removal and heat transfer, in what has been termed electric-field-enhanced (EFE) jumping-droplet condensation. However, achieving optimal EFE conditions for enhanced heat transfer requires capturing the details of transport processes that is currently lacking. While a comprehensive model has been developed for condensation on micro/nanostructured surfaces, it cannot be applied for EFE condensation due to the dynamic droplet-vapor-electric field interactions. In this work, we developed a comprehensive physical model for EFE condensation on superhydrophobic surfaces by incorporating individual droplet motion, electrode geometry, jumping frequency, field strength, and condensate vapor-flow dynamics. As a first step toward our model, we simulated jumping droplet motion with no external electric field and validated our theoretical droplet trajectories to experimentally obtained trajectories, showing excellent temporal and spatial agreement. We then incorporated the external electric field into our model and considered the effects of jumping droplet size, electrode size and geometry, condensation heat flux, and droplet jumping direction. Our model suggests that smaller jumping droplet sizes and condensation heat fluxes require less work input to be removed by the external fields. Furthermore, the results suggest that EFE electrodes can be optimized such that the work input is minimized depending on the condensation heat flux. To analyze overall efficiency, we defined an incremental coefficient of performance and showed that it is very high (∼10(6)) for EFE condensation. We finally proposed mechanisms

  18. Design and Fabrication of a Hybrid Superhydrophobic-Hydrophilic Surface That Exhibits Stable Dropwise Condensation.

    Science.gov (United States)

    Mondal, Bikash; Mac Giolla Eain, Marc; Xu, QianFeng; Egan, Vanessa M; Punch, Jeff; Lyons, Alan M

    2015-10-28

    Condensation of water vapor is an essential process in power generation, water collection, and thermal management. Dropwise condensation, where condensed droplets are removed from the surface before coalescing into a film, has been shown to increase the heat transfer efficiency and water collection ability of many surfaces. Numerous efforts have been made to create surfaces which can promote dropwise condensation, including superhydrophobic surfaces on which water droplets are highly mobile. However, the challenge with using such surfaces in condensing environments is that hydrophobic coatings can degrade and/or water droplets on superhydrophobic surfaces transition from the mobile Cassie to the wetted Wenzel state over time and condensation shifts to a less-effective filmwise mechanism. To meet the need for a heat-transfer surface that can maintain stable dropwise condensation, we designed and fabricated a hybrid superhydrophobic-hydrophilic surface. An array of hydrophilic needles, thermally connected to a heat sink, was forced through a robust superhydrophobic polymer film. Condensation occurs preferentially on the needle surface due to differences in wettability and temperature. As the droplet grows, the liquid drop on the needle remains in the Cassie state and does not wet the underlying superhydrophobic surface. The water collection rate on this surface was studied using different surface tilt angles, needle array pitch values, and needle heights. Water condensation rates on the hybrid surface were shown to be 4 times greater than for a planar copper surface and twice as large for silanized silicon or superhydrophobic surfaces without hydrophilic features. A convection-conduction heat transfer model was developed; predicted water condensation rates were in good agreement with experimental observations. This type of hybrid superhydrophobic-hydrophilic surface with a larger array of needles is low-cost, robust, and scalable and so could be used for heat

  19. Familial transmission of a ring chromosome 21

    DEFF Research Database (Denmark)

    Hertz, Jens Michael

    1987-01-01

    A ring chromosome 21 was found in a phenotypically normal mother and her son. The clinical findings in the son were bilateral retention of the testes and a slightly delayed puberty onset. Consequences of a ring formation of a chromosome 21 in phenotypically normal patients are presented...... and discussed, and the previously reported cases of familially transmitted G-group ring chromosomes are reviewed....

  20. The mean condensate heat resistance of dropwise condensation with flowing inert gases

    NARCIS (Netherlands)

    Geld, van der C.W.M.; Brouwers, H.J.H.

    1995-01-01

    The quantification of the condensate heat resistance is studied for dropwise condensation from flowing air-steam mixtures. Flows are essentially laminar and stable with gas Reynolds numbers around 900 and 2000. The condensate shaping up as hemispheres on a plastic plane wall and the presence of iner

  1. C-banding and fluorescent in situ hybridization with rDNA sequences in chromosomes of Cycloneda sanguinea Linnaeus (Coleoptera, Coccinellidae

    Directory of Open Access Journals (Sweden)

    Eliane Mariza Dortas Maffei

    2004-01-01

    Full Text Available The aim of this study was to describe mitotic and meiotic chromosomes of Cycloneda sanguinea using C-banding, fluorescent in situ hybridization (FISH rDNA probes, and sequential FISH/Ag-NOR staining. The chromosome number was 2n = 18 + XX for females and 2n = 18 + Xy for males. The X chromosome was metacentric and the Y chromosome was very small. During meiosis, the karyotypic meioformula was n = 9 + Xy p, and sex chromosomes configured a parachute at metaphase I. At the beginning of pachytene, bivalents were still individualized, and sex chromosomes were associated end-to-end through the heteropycnotic region of the X chromosome. Later in pachytene, further condensation led to the formation of a pseudo-ring by the sex bivalent. All chromosomes showed pericentromeric heterochromatin. FISH and sequential FISH/Ag-NOR staining evidenced the location of the nucleolar organizer region in one pair of autosomes (at spermatogonial metaphase. During meiosis, these genes were mapped to a region outside the sex vesicle by FISH, although Xy p was deeply stained with silver at metaphase I. These results suggest that these argyrophilic substances are of a nucleolar protein nature, and seem to be synthesized by a pair of autosomes and imported during meiosis (prophase I to the sex pair, during the association of the sex chromosomes.

  2. Prediction of steam condensation in the presence of noncondensable gases using a CFD-based approach

    Energy Technology Data Exchange (ETDEWEB)

    Dehbi, A., E-mail: abdel.dehbi@psi.ch [Laboratory for Thermal-Hydraulics, Paul Scherrer Institut, Villigen 5232 (Switzerland); Janasz, F., E-mail: filip.janasz@psi.ch [Laboratory for Thermal-Hydraulics, Paul Scherrer Institut, Villigen 5232 (Switzerland); Bell, B., E-mail: brian.bell@ansys.com [ANSYS Inc., Lebanon, NH 03766 (United States)

    2013-05-15

    Highlights: ► A model of condensation with noncondensable gases is integrated in the Fluent code. ► Condensation is modeled as sink terms in the conservation equations. ► A best-estimate parameter is proposed for heat transfer enhancement due to suction. ► Validation is conducted for a wide range of flow conditions and geometries. ► Predictions are in good agreement with experimental correlations. -- Abstract: We integrate in the ANSYS CFD code Fluent a model for wall condensation from a vapor–noncondensable gas mixture. The condensation phenomenon is modeled from first principles as sink terms for the mass, momentum, species and energy conservation equations. The condensation rate is obtained by requiring the condensate–gas interface to be impermeable to the noncondensable gas. The model assumes in addition that the thermal resistance of the liquid film is negligible, and hence the predictions are only valid for relatively large mass fractions of the noncondensable gas (above 0.1). When the condensation rates are high, a best-estimate suction correction factor is proposed for CFD codes that impose the no-slip boundary conditions at the wall surfaces. In such a way, the enhancement in the heat transfer due to suction is accounted for. We first simulate condensation in laminar and turbulent forced flows along a cold flat plate. More challenging simulations are subsequently conducted for the case where vapor is introduced into closed vessels containing a noncondensable gas and in which stand condensing surfaces held at constant cold temperature. The flow transient is computed until steady conditions are reached, at which point the condensation flow rate equals the injected steam flow rate. Overall, the predicted heat transfer rates are in good agreement with available analytical solutions as well as experimental correlations. CFD Best Practice Guidelines are followed to a large extent. In particular, a hierarchy of grids is used to ensure mesh

  3. Down-Turner Syndrome: A Case with Double Monoclonal Chromosomal Abnormality.

    Science.gov (United States)

    Manassero-Morales, Gioconda; Alvarez-Manassero, Denisse; Merino-Luna, Alfredo

    2016-01-01

    Introduction. The coexistence of Down and Turner syndromes due to double chromosome aneuploidy is very rare; it is even more rare to find the presence of a double monoclonal chromosomal abnormality. Objective. To report a unique case of double monoclonal chromosomal abnormality with trisomy of chromosome 21 and an X ring chromosome in all cells studied; no previous report has been found. Case Report. Female, 28 months old, with pathological short stature from birth, with the following dysmorphic features: tilted upward palpebral fissures, short neck, brachycephaly, and low-set ears. During the neonatal period, the infant presented generalized hypotonia and lymphedema of hands and feet. Karyotype showed 47,X,r(X),+21 [30]. Conclusion. Clinical features of both Down and Turner syndromes were found, highlighting short stature that has remained below 3 z score from birth to the present, associated with delayed psychomotor development. G-banded karyotype analysis in peripheral blood is essential for a definitive diagnosis.

  4. Down-Turner Syndrome: A Case with Double Monoclonal Chromosomal Abnormality.

    Science.gov (United States)

    Manassero-Morales, Gioconda; Alvarez-Manassero, Denisse; Merino-Luna, Alfredo

    2016-01-01

    Introduction. The coexistence of Down and Turner syndromes due to double chromosome aneuploidy is very rare; it is even more rare to find the presence of a double monoclonal chromosomal abnormality. Objective. To report a unique case of double monoclonal chromosomal abnormality with trisomy of chromosome 21 and an X ring chromosome in all cells studied; no previous report has been found. Case Report. Female, 28 months old, with pathological short stature from birth, with the following dysmorphic features: tilted upward palpebral fissures, short neck, brachycephaly, and low-set ears. During the neonatal period, the infant presented generalized hypotonia and lymphedema of hands and feet. Karyotype showed 47,X,r(X),+21 [30]. Conclusion. Clinical features of both Down and Turner syndromes were found, highlighting short stature that has remained below 3 z score from birth to the present, associated with delayed psychomotor development. G-banded karyotype analysis in peripheral blood is essential for a definitive diagnosis. PMID:27672470

  5. Down-Turner Syndrome: A Case with Double Monoclonal Chromosomal Abnormality

    Science.gov (United States)

    Alvarez-Manassero, Denisse; Merino-Luna, Alfredo

    2016-01-01

    Introduction. The coexistence of Down and Turner syndromes due to double chromosome aneuploidy is very rare; it is even more rare to find the presence of a double monoclonal chromosomal abnormality. Objective. To report a unique case of double monoclonal chromosomal abnormality with trisomy of chromosome 21 and an X ring chromosome in all cells studied; no previous report has been found. Case Report. Female, 28 months old, with pathological short stature from birth, with the following dysmorphic features: tilted upward palpebral fissures, short neck, brachycephaly, and low-set ears. During the neonatal period, the infant presented generalized hypotonia and lymphedema of hands and feet. Karyotype showed 47,X,r(X),+21 [30]. Conclusion. Clinical features of both Down and Turner syndromes were found, highlighting short stature that has remained below 3 z score from birth to the present, associated with delayed psychomotor development. G-banded karyotype analysis in peripheral blood is essential for a definitive diagnosis. PMID:27672470

  6. Down-Turner Syndrome: A Case with Double Monoclonal Chromosomal Abnormality

    Directory of Open Access Journals (Sweden)

    Gioconda Manassero-Morales

    2016-01-01

    Full Text Available Introduction. The coexistence of Down and Turner syndromes due to double chromosome aneuploidy is very rare; it is even more rare to find the presence of a double monoclonal chromosomal abnormality. Objective. To report a unique case of double monoclonal chromosomal abnormality with trisomy of chromosome 21 and an X ring chromosome in all cells studied; no previous report has been found. Case Report. Female, 28 months old, with pathological short stature from birth, with the following dysmorphic features: tilted upward palpebral fissures, short neck, brachycephaly, and low-set ears. During the neonatal period, the infant presented generalized hypotonia and lymphedema of hands and feet. Karyotype showed 47,X,r(X,+21 [30]. Conclusion. Clinical features of both Down and Turner syndromes were found, highlighting short stature that has remained below 3 z score from birth to the present, associated with delayed psychomotor development. G-banded karyotype analysis in peripheral blood is essential for a definitive diagnosis.

  7. COMBINED COOLING OF CONDENSATION UNIT OF VAPOR COMPRESSION REFRIGERATION STATIONS

    OpenAIRE

    Maksimenko V.A.; Fot A.N.

    2011-01-01

    In large refrigeration systems it is used to compose condensation node with water-cooled condensers. In actual conditions of deficit and increase of cooling water price it is appropriate combined cooling of condensation unit on existing and developed large refrigeration facilities. Combined cooling of condensation unit allows stabilizing the condensing pressure and significantly reducing the consumption of cooling water.

  8. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae ( Teleostei , Characidae )

    OpenAIRE

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko,Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Abstract B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of...

  9. Chromosomal instability in Streptomyces avermitilis: major deletion in the central region and stable circularized chromosome

    Directory of Open Access Journals (Sweden)

    Wen Ying

    2010-07-01

    Full Text Available Abstract Background The chromosome of Streptomyces has been shown to be unstable, frequently undergoing gross chromosomal rearrangements. However, the mechanisms underlying this phenomenon remain unclear, with previous studies focused on two chromosomal ends as targets for rearrangements. Here we investigated chromosomal instability of Streptomyces avermitilis, an important producer of avermectins, and characterized four gross chromosomal rearrangement events, including a major deletion in the central region. The present findings provide a valuable contribution to the mechanistic study of genetic instability in Streptomyces. Results Thirty randomly-selected "bald" mutants derived from the wild-type strain all contained gross chromosomal rearrangements of various types. One of the bald mutants, SA1-8, had the same linear chromosomal structure as the high avermectin-producing mutant 76-9. Chromosomes of both strains displayed at least three independent chromosomal rearrangements, including chromosomal arm replacement to form new 88-kb terminal inverted repeats (TIRs, and two major deletions. One of the deletions eliminated the 36-kb central region of the chromosome, but surprisingly did not affect viability of the cells. The other deletion (74-kb was internal to the right chromosomal arm. The chromosome of another bald mutant, SA1-6, was circularized with deletions at both ends. No obvious homology was found in all fusion sequences. Generational stability analysis showed that the chromosomal structure of SA1-8 and SA1-6 was stable. Conclusions Various chromosomal rearrangements, including chromosomal arm replacement, interstitial deletions and chromosomal circularization, occurred in S. avermitilis by non-homologous recombination. The finding of an inner deletion involving in the central region of S. avermitilis chromosome suggests that the entire Streptomyces chromosome may be the target for rearrangements, which are not limited, as previously

  10. Profilo trascrizionale dei microsporociti del mutante meiotic chromosome condensation di Arabidopsis mediante laser microdissection microarray (LMM)

    OpenAIRE

    Barra, Lucia

    2008-01-01

    I meccanismi molecolari che regolano la meiosi nelle piante sono ancora poco noti. Finora sono stati isolati circa cinquanta geni meiotici vegetali soprattutto tramite mutanti inserzionali di Arabidopsis thaliana con approcci di “forward” e “reverse genetics”, in quest’ultimo caso utilizzando strategie comparative con organismi modello. Studi recenti evidenziano un coinvolgimento delle modificazioni istoniche post-traduzionali, tra cui l’acetilazione, nel processo meiotico di diversi organism...

  11. Homologous recombination, sister chromatid cohesion, and chromosome condensation in mammalian meiosis

    NARCIS (Netherlands)

    Eijpe, M.

    2002-01-01

    In the life cycle of sexually reproducing eukaryotes, haploid and diploid generations of cells alternate. Two types of cell division occur in such a life cycle: mitosis and meiosis. They are compared in chapter 1 . Haploid and diploid cells can multiply by mitoses.

  12. CFD simulation of water vapour condensation in the presence of non-condensable gas in vertical cylindrical condensers.

    Science.gov (United States)

    Li, Jun-De

    2013-02-01

    This paper presents the simulation of the condensation of water vapour in the presence of non-condensable gas using computational fluid dynamics (CFD) for turbulent flows in a vertical cylindrical condenser tube. The simulation accounts for the turbulent flow of the gas mixture, the condenser wall and the turbulent flow of the coolant in the annular channel with no assumptions of constant wall temperature or heat flux. The condensate film is assumed to occupy a negligible volume and its effect on the condensation of the water vapour has been taken into account by imposing a set of boundary conditions. A new strategy is used to overcome the limitation of the currently available commercial CFD package to solve the simultaneous simulation of flows involving multispecies and fluids of gas and liquid in separate channels. The results from the CFD simulations are compared with the experimental results from the literature for the condensation of water vapour with air as the non-condensable gas and for inlet mass fraction of the water vapour from 0.66 to 0.98. The CFD simulation results in general agree well with the directly measured quantities and it is found that the variation of heat flux in the condenser tube is more complex than a simple polynomial curve fit. The CFD results also show that, at least for flows involving high water vapour content, the axial velocity of the gas mixture at the interface between the gas mixture and the condensate film is in general not small and cannot be neglected. PMID:24850953

  13. Simple approximations for condensational growth

    Energy Technology Data Exchange (ETDEWEB)

    Kostinski, A B [Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931-1200 (United States)], E-mail: alex.kostinski@mtu.edu

    2009-01-15

    A simple geometric argument relating to the liquid water content of clouds is given. The phase relaxation time and the nature of the quasi-steady approximation for the diffusional growth of cloud drops are elucidated directly in terms of water vapor concentration. Spatial gradients of vapor concentration, inherent in the notion of quasi-steady growth, are discussed and we argue for an occasional reversal of the traditional point of view: rather than a drop growing in response to a given supersaturation, the observed values of the supersaturation in clouds are the result of a vapor field adjusting to droplet growth. Our perspective is illustrated by comparing the exponential decay of condensation trails with a quasi-steady regime of cirrus clouds. The role of aerosol loading in decreasing relaxation times and increasing the rate of growth of the liquid water content is also discussed.

  14. DEHYDRATION CONDENSATION IN AQUEOUS SOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Steinman, Gary; Kenyon, Dean H.; Calvin, Melvin

    1965-04-01

    EARLIER investigations have demonstrated that di-cyandiamide (DCDA), the dimer of cyanamide, can successfully promote the dehydration condensation of: (1) glucose and orthophosphate to give glucose-6-phosphate; (2) adenosine and orthophosphate to give adenosine-5'-monophosphate; (3) orthophosphate to give pyrophosphate; (4) alanine to give alanylalanine and alanylalanylalanine. These reactions were carried out in dilute aqueous solutions in the dark. (It was also demonstrated that the combination of ultra-violet light and dicyandiamide could promote the synthesis of dipeptides. This observation has since been confirmed by other investigators.) These experiments were designed to demonstrate one possible means by which such compounds could have been formed on the prebiotic Earth, thus providing materials needed for the origin of living systems. Dicyandiamide itself could have been, present on the primitive Earth as was demonstrated with the ultra-violet irradiation of cyanide solution.

  15. Positronium formation in condensed matter

    International Nuclear Information System (INIS)

    AMOC (age-momentum correlation) studies of the slowing-down of positronium in condensed matter have demonstrated that positronium formation does not require special sites (e.g., 'free volumes') and diffusion of thermalized e+ to these sites. The differences in the energies E0 at which ps becomes 'permanent' (i.e., does no longer break up into its constituents) between disordered (e.g., organic liquids) and highly ordered (e.g., rare-gas crystals) Ps-formers are explained by the different character of the forces acting on the constituents. It is proposed that information on the break-up may be obtained from the relaxation of the positron spin polarization and that very long slowing-down times may be investigated by ACAR-based AMOC measurements. (orig.)

  16. Condensation on Slippery Asymmetric Bumps

    CERN Document Server

    Park, Kyoo-Chul; He, Neil; Aizenberg, Joanna

    2015-01-01

    Bumps are omnipresent from human skin to the geological structures on planets, which offer distinct advantages in numerous phenomena including structural color, drag reduction, and extreme wettability. Although the topographical parameters of bumps such as radius of curvature of convex regions significantly influence various phenomena including anti-reflective structures and contact time of impacting droplets, the effect of the detailed bump topography on growth and transport of condensates have not been clearly understood. Inspired by the millimetric bumps of the Namib Desert beetle, here we report the identified role of radius of curvature and width of bumps with homogeneous surface wettability in growth rate, coalescence and transport of water droplets. Further rational design of asymmetric convex topography and synergetic combination with slippery coating simultaneously enable self-transport, leading to unseen five-fold higher growth rate and an order of magnitude faster shedding time of droplets compared...

  17. Chemical remediation of beech condensates.

    Science.gov (United States)

    Irmouli, Mohammed; Haluk, Jean Pierre

    2005-01-01

    In the present work, beech wood condensates are separated from the aqueous phase. Experimental results reveal an electrostatic interaction between the oppositely charged wood extracts after oxidation and Ca(OH)(2). The increase in aqueous phase pH resulted in enhanced removal of wood extracts from water. The polarographic assays were carried out at 25 degrees C using a Gilson oxygraph equipped with a Clark electrode in order to determine the oxygen uptake during the oxidation reaction. The effect of pH is explained based on oxygen uptake. The organic compounds found in the aqueous effluent are responsible for the brown color. The objective of this study is to find the optimum pH to eliminate the wood extracts from the liquid effluents. PMID:15567404

  18. Kaon Condensation in Dense Matter

    CERN Document Server

    Carlson, J; Pandharipande, V R

    2001-01-01

    The kaon energy in neutron matter is calculated analytically with the Klein-Gordon equation, by making a Wigner-Seitz cell approximation and employing a $K^-N$ square well potential. The transition from the low density Lenz potential, proportional to scattering length, to the high density Hartree potential is found to begin at fairly low densities. Exact non-relativistic calculations of the kaon energy in a simple cubic crystal of neutrons are used to test the Wigner-Seitz and the Ericson-Ericson approximation methods. All the calculations indicate that by $\\sim 4$ times nuclear matter density the Hartree limit is reached, and as the Hartree potential is less attractive, the density for kaon condensation appears to higher than previously estimated. Effects of a hypothetical repulsive core in the $K^-N$ potential are also studied.

  19. Nucleation and condensation model development

    Energy Technology Data Exchange (ETDEWEB)

    Fry, H.; Lyman, J.; Breshears, D.; Zerkle, D.; Wilson, C.; Hewitt, C.; Gallegos, D.

    1996-09-01

    This is a final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The purpose of this project was to bring to maturity a theoretical and experimental capability of the Laboratory to perform basic research in nucleation and condensation of water vapor. This report provides a general description of this capability and summarizes specific work in two areas: development and use of a combustive flow facility (CFF) to measure water monomer depletion in a supersonic nozzle and nucleation pulse experiments for investigation of transport effects on water droplet growth dynamics. The later work was performed in collaboration with Dr. Wehrner Strey in Goettingen, Germany. Preliminary water absorption data from the CFF experiment are presented. The nucleation pulse data is described along with an analysis that shows under the condition of the experiment the growth rate of water droplets is limited by monomer diffusion.

  20. Topoisomerase IIα in chromosome instability and personalized cancer therapy.

    Science.gov (United States)

    Chen, T; Sun, Y; Ji, P; Kopetz, S; Zhang, W

    2015-07-30

    Genome instability is a hallmark of cancer cells. Chromosome instability (CIN), which is often mutually exclusive from hypermutation genotypes, represents a distinct subtype of genome instability. Hypermutations in cancer cells are due to defects in DNA repair genes, but the cause of CIN is still elusive. However, because of the extensive chromosomal abnormalities associated with CIN, its cause is likely a defect in a network of genes that regulate mitotic checkpoints and chromosomal organization and segregation. Emerging evidence has shown that the chromosomal decatenation checkpoint, which is critical for chromatin untangling and packing during genetic material duplication, is defective in cancer cells with CIN. The decatenation checkpoint is known to be regulated by a family of enzymes called topoisomerases. Among them, the gene encoding topoisomerase IIα (TOP2A) is commonly altered at both gene copy number and gene expression level in cancer cells. Thus, abnormal alterations of TOP2A, its interacting proteins, and its modifications may have a critical role in CIN in human cancers. Clinically, a large arsenal of topoisomerase inhibitors has been used to suppress DNA replication in cancer. However, they often lead to the secondary development of leukemia because of their effect on the chromosomal decatenation checkpoint. Therefore, topoisomerase drugs must be used judiciously and administered on an individual basis. In this review, we highlight the biological function of TOP2A in chromosome segregation and the mechanisms that regulate this enzyme's expression and activity. We also review the roles of TOP2A and related proteins in human cancers, and raise a perspective for how to target TOP2A in personalized cancer therapy. PMID:25328138

  1. Global cloud condensation nuclei influenced by carbonaceous combustion aerosol

    Directory of Open Access Journals (Sweden)

    D. V. Spracklen

    2011-03-01

    Full Text Available Black carbon in carbonaceous combustion aerosol warms the climate by absorbing solar radiation, meaning reductions in black carbon emissions are often perceived as an attractive global warming mitigation option. However, carbonaceous combustion aerosol can also act as cloud condensation nuclei (particles upon which cloud drops form so they also cool the climate by increasing cloud albedo. The net radiative effect of carbonaceous combustion aerosol is uncertain because their contribution to cloud drops has not been evaluated on the global scale. By combining extensive observations of cloud condensation nuclei concentrations and a global aerosol model, we show that carbonaceous combustion aerosol accounts for more than half of global cloud condensation nuclei. The evaluated model predicts that wildfire and pollution (fossil fuel and biofuel carbonaceous combustion aerosol causes a global mean aerosol indirect effect of −0.34 W m−2 due to changes in cloud albedo, with pollution sources alone causing a global mean aerosol indirect effect of −0.23 W m−2. The small size of carbonaceous combustion particles from pollution sources means that whilst they account for only one-third of the emitted mass from these sources they cause two-thirds of the cloud albedo indirect effect that is due to carbonaceous combustion aerosol. This cooling effect must be accounted for to ensure that black carbon emissions controls that reduce the high number concentrations of small pollution particles have the desired net effect on climate.

  2. Statistical physics and condensed matter

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This document is divided into 4 sections: 1) General aspects of statistical physics. The themes include: possible geometrical structures of thermodynamics, the thermodynamical foundation of quantum measurement, transport phenomena (kinetic theory, hydrodynamics and turbulence) and out of equilibrium systems (stochastic dynamics and turbulence). The techniques involved here are typical of applied analysis: stability criteria, mode decomposition, shocks and stochastic equations. 2) Disordered, glassy and granular systems: statics and dynamics. The complexity of the systems can be studied through the structure of their phase space. The geometry of this phase space is studied in several works: the overlap distribution can now be computed with a very high precision; the boundary energy between low lying states does not behave like in ordinary systems; and the Edward's hypothesis of equi-probability of low lying metastable states is invalidated. The phenomenon of aging, characteristic of glassy dynamics, is studied in several models. Dynamics of biological systems or of fracture is shown to bear some resemblance with that of disordered systems. 3) Quantum systems. The themes include: mesoscopic superconductors, supersymmetric approach to strongly correlated electrons, quantum criticality and heavy fermion compounds, optical sum rule violation in the cuprates, heat capacity of lattice spin models from high-temperature series expansion, Lieb-Schultz-Mattis theorem in dimension larger than one, quantum Hall effect, Bose-Einstein condensation and multiple-spin exchange model on the triangular lattice. 4) Soft condensed matter and biological systems. Path integral representations are invaluable to describe polymers, proteins and self-avoiding membranes. Using these methods, problems as diverse as the titration of a weak poly-acid by a strong base, the denaturation transition of DNA or bridge-hopping in conducting polymers have been addressed. The problems of RNA folding

  3. Polymer models of chromosome (re)organization

    Science.gov (United States)

    Mirny, Leonid

    Chromosome Conformation Capture technique (Hi-C) provides comprehensive information about frequencies of spatial interactions between genomic loci. Inferring 3D organization of chromosomes from these data is a challenging biophysical problem. We develop a top-down approach to biophysical modeling of chromosomes. Starting with a minimal set of biologically motivated interactions we build ensembles of polymer conformations that can reproduce major features observed in Hi-C experiments. I will present our work on modeling organization of human metaphase and interphase chromosomes. Our works suggests that active processes of loop extrusion can be a universal mechanism responsible for formation of domains in interphase and chromosome compaction in metaphase.

  4. Hydrophilic structures for condensation management in appliances

    Science.gov (United States)

    Kuehl, Steven John; Vonderhaar, John J.; Wu, Guolian; Wu, Mianxue

    2016-02-02

    An appliance that includes a cabinet having an exterior surface; a refrigeration compartment located within the cabinet; and a hydrophilic structure disposed on the exterior surface. The hydrophilic structure is configured to spread condensation. The appliance further includes a wicking structure located in proximity to the hydrophilic structure, and the wicking structure is configured to receive the condensation.

  5. Creating massive entanglement of Bose condensed atoms

    OpenAIRE

    Helmerson, Kristian; You, Li

    2001-01-01

    We propose a direct, coherent coupling scheme that can create massively entangled states of Bose-Einstein condensed atoms. Our idea is based on an effective interaction between two atoms from coherent Raman processes through a (two atom) molecular intermediate state. We compare our scheme with other recent proposals for generation of massive entanglement of Bose condensed atoms.

  6. Soliton resonance in bose-einstein condensate

    Science.gov (United States)

    Zak, Michail; Kulikov, I.

    2002-01-01

    A new phenomenon in nonlinear dispersive systems, including a Bose-Einstein Condensate (BEC), has been described. It is based upon a resonance between an externally induced soliton and 'eigen-solitons' of the homogeneous cubic Schrodinger equation. There have been shown that a moving source of positive /negative potential induces bright /dark solitons in an attractive / repulsive Bose condensate.

  7. Quark condensate in two-flavor QCD

    Energy Technology Data Exchange (ETDEWEB)

    DeGrand, T.; Liu, Z. [Colorado Univ., Boulder, CO (United States). Dept. of Physics; Schaefer, S. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC

    2006-09-15

    We compute the condensate in QCD with two flavors of dynamical fermions using numerical simulation. The simulations use overlap fermions, and the condensate is extracted by fitting the distribution of low lying eigenvalues of the Dirac operator in sectors of fixed topological charge to the predictions of Random Matrix Theory. (orig.)

  8. Gigantic excitation of Bose-Einstein condensate

    CERN Document Server

    Karkuszewski, Z P; Zakrzewski, J; Karkuszewski, Zbyszek P.; Sacha, Krzysztof; Zakrzewski, Jakub

    2001-01-01

    It is shown that by a modification of the trapping potential one may excite Bose-Einstein condensate to a state in which atomic external degrees of freedom are predominantly in the {\\it excited} trap state. Such an excited condensate can be prepared experimentally --- it requires only a proper change in time of the potential in atomic traps, as realized in laboratories already.

  9. Chromosome painting of Z and W sex chromosomes in Characidium (Characiformes, Crenuchidae).

    Science.gov (United States)

    Pazian, Marlon F; Shimabukuro-Dias, Cristiane Kioko; Pansonato-Alves, José Carlos; Oliveira, Claudio; Foresti, Fausto

    2013-03-01

    Some species of the genus Characidium have heteromorphic ZZ/ZW sex chromosomes with a totally heterochromatic W chromosome. Methods for chromosome microdissection associated with chromosome painting have become important tools for cytogenetic studies in Neotropical fish. In Characidium cf. fasciatum, the Z chromosome contains a pericentromeric heterochromatin block, whereas the W chromosome is completely heterochromatic. Therefore, a probe was produced from the W chromosome through microdissection and degenerate oligonucleotide-primed polymerase chain reaction amplification. FISH was performed using the W probe on the chromosomes of specimens of this species. This revealed expressive marks in the pericentromeric region of the Z chromosome as well as a completely painted W chromosome. When applying the same probe on chromosome preparations of C. cf. gomesi and Characidium sp., a pattern similar to C. cf. fasciatum was found, while C. cf. zebra, C. cf. lagosantense and Crenuchus spilurus species showed no hybridization signals. Structural changes in the chromosomes of an ancestral sexual system in the group that includes the species C. cf. gomesi, C. cf. fasciatum and Characidium sp., could have contributed to the process of speciation and could represent a causal mechanism of chromosomal diversification in this group. The heterochromatinization process possibly began in homomorphic and homologous chromosomes of an ancestral form, and this process could have given rise to the current patterns found in the species with sex chromosome heteromorphism.

  10. Condensed Matter Theories - Volume 22

    Science.gov (United States)

    Reinholz, Heidi; Röpke, Gerd; de Llano, Manuel

    2007-09-01

    pt. A. Fermi liquids. Pressure comparison between the spherical cellular model and the Thomas-Fermi model / G.A. Baker, Jr. Pair excitations and vertex corrections in Fermi fluids and the dynamic structure function of two-dimension 3He / H.M. Böhm, H. Godfrin, E. Krotscheck, H.J. Lauter, M. Meschke and M. Panholzer. Condensation of helium in wedges / E.S. Hernádez ... [et al.]. Non-Fermi liquid behavior from the Fermi-liquid approach / V.A. Khodel ... [et al.]. Theory of third sound and stability of thin 3He-4He superfluid films / E. Krotscheck and M.D. Miller. Pairing in asymmetrical Fermi systems / K.F. Quader and R. Liao. Ground-state properties of small 3He drops from quantum Monte Carlo simulations / E. Sola, J. Casulleras and J. Boronat. Ground-state energy and compressibility of a disordered two-dimensional electron gas / Tanatar ... [et al.]. Quasiexcitons in photoluminescence of incompressible quantum liquids / A. Wójs, A.G ladysiewicz and J.J. Quinn -- pt. B. Bose liquids. Quantum Boltzmann liquids / K.A. Gernoth, M L. Ristig and T. Lindenau. Condensate fraction in the dynamic structure function of Bose fluids / M. Saarela, F. Mazzanti and V. Apaja -- pt. C. Strongly-correlated electronic systems. Electron gas in high-field nanoscopic transport: metallic carbon nanotubes / F. Green and D. Neilson. Evolution and destruction of the Kondo effect in a capacitively coupled double dot system / D.E. Logan and M.R. Galpin. The method of increments-a wavefunction-based Ab-Initio correlation method for solids / B. Paulus. Fractionally charged excitations on frustrated lattices / E. Runge, F. Pollmann and P. Fulde. 5f Electrons in actinides: dual nature and photoemission spectra / G. Zwicknagl -- pt. D. Magnetism. Magnetism in disordered two-dimensional Kondo-Necklace / W. Brenig. On the de Haas-can Alphen oscillation in 2D / S. Fujita and D.L. Morabito. Dynamics in one-dimensional spin systems-density matrix reformalization group study / S. Nishimoto and M

  11. Theory of excitations of the condensate and non-condensate at finite temperatures

    OpenAIRE

    Griffin, Allan

    1999-01-01

    We give an overview of the current theory of collective modes in trapped atomic gases at finite temperatures, when the dynamics of the condensate and non-condensate must both be considered. A simple introduction is given to the quantum field formulation of the dynamics of an interacting Bose-condensed system, based on equations of motion for the condensate wavefunction and single-particle Green's functions for the non-condensate atoms. We discuss the nature of excitations in the mean-field co...

  12. Interferometry with Bose-Einstein Condensates in Microgravity

    CERN Document Server

    Müntinga, H; Krutzik, M; Wenzlawski, A; Arnold, S; Becker, D; Bongs, K; Dittus, H; Duncker, H; Gaaloul, N; Gherasim, C; Giese, E; Grzeschik, C; Hänsch, T W; Hellmig, O; Herr, W; Herrmann, S; Kajari, E; Kleinert, S; Lämmerzahl, C; Lewoczko-Adamczyk, W; Malcolm, J; Meyer, N; Nolte, R; Peters, A; Popp, M; Reichel, J; Roura, A; Rudolph, J; Schiemangk, M; Schneider, M; Seidel, S T; Sengstock, K; Tamma, V; Valenzuela, T; Vogel, A; Walser, R; Wendrich, T; Windpassinger, P; Zeller, W; van Zoest, T; Ertmer, W; Schleich, W P; Rasel, E M

    2013-01-01

    Atom interferometers covering macroscopic domains of space-time are a spectacular manifestation of the wave nature of matter. Due to their unique coherence properties, Bose-Einstein condensates are ideal sources for an atom interferometer in extended free fall. In this paper we report on the realization of an asymmetric Mach-Zehnder interferometer operated with a Bose-Einstein condensate in microgravity. The resulting interference pattern is similar to the one in the far-field of a double-slit and shows a linear scaling with the time the wave packets expand. We employ delta-kick cooling in order to enhance the signal and extend our atom interferometer. Our experiments demonstrate the high potential of interferometers operated with quantum gases for probing the fundamental concepts of quantum mechanics and general relativity.

  13. Gluon condensate, modified gravity, and the accelerating Universe

    CERN Document Server

    Klinkhamer, F R

    2009-01-01

    The dynamics of a gravitating gluon condensate q is studied in the context of a spatially flat Friedmann-Robertson-Walker universe. With a quadratic approximation of the gluon-condensate vacuum energy density \\rho_{V}(q) near the equilibrium value q_{0} and a small modified-gravity coupling constant \\eta of a nonanalytic \\tilde{f}(R,q) term in the action, an "accelerating universe" is obtained which more or less resembles the present Universe. The unknown component 'X' of this model universe (here, due to the combined effects of vacuum energy density and modified gravity) has an effective equation-of-state parameter \\bar{w}_{X} which is found to evolve towards the value -1 from above.

  14. Wealth condensation in a Barabasi-Albert network

    Science.gov (United States)

    Vázquez-Montejo, J.; Huerta-Quintanilla, R.; Rodríguez-Achach, M.

    2010-04-01

    We study the flow of money among agents in a Barabasi-Albert (BA) scale free network, where each network node represents an agent and money exchange interactions are established through links. The system allows money trade between two agents at a time, betting a fraction f of the poorer’s agent wealth. We also allow for the bet to be biased, giving the poorer agent a winning probability p. In the no network case there is a phase transition involving a relationship between p and f. In the networked case, we also found a condensation interface, however, this is not a complete condensation due to the presence of clusters in the network and its topology. As can be expected, the winner is always a well-connected agent, but we also found that the mean wealth decreases with the agents’ connectivity.

  15. Cavity Quantum Electrodynamics of Continuously Monitored Bose-Condensed Atoms

    Directory of Open Access Journals (Sweden)

    Mark D. Lee

    2015-09-01

    Full Text Available We study cavity quantum electrodynamics of Bose-condensed atoms that are subjected to continuous monitoring of the light leaking out of the cavity. Due to a given detection record of each stochastic realization, individual runs spontaneously break the symmetry of the spatial profile of the atom cloud and this symmetry can be restored by considering ensemble averages over many realizations. We show that the cavity optomechanical excitations of the condensate can be engineered to target specific collective modes. This is achieved by exploiting the spatial structure and symmetries of the collective modes and light fields. The cavity fields can be utilized both for strong driving of the collective modes and for their measurement. In the weak excitation limit the condensate–cavity system may be employed as a sensitive phonon detector which operates by counting photons outside the cavity that have been selectively scattered by desired phonons.

  16. Bose–Einstein condensation in a minimal inhomogeneous system

    International Nuclear Information System (INIS)

    We study the effects of repulsive interaction and disorder on bosons in a two-site Bose–Hubbard system, which provides a simple model of the dirty boson problem. By comparison with exact numerical results, we demonstrate how a straightforward application of the Bogoliubov approximation fails even to deliver a qualitatively correct picture. It wrongly predicts an increase of the condensate depletion due to disorder. We show that, in the presence of disorder, the noncommutative character of the condensate operator has to be retained for a correct description of the system. While these corrections to a simple meanfield Bogoliubov theory are usually small in extended systems, we show that care has to be taken when modeling small inhomogeneous Bose systems. (paper)

  17. Gravitino condensation, supersymmetry breaking and inflation

    CERN Document Server

    Houston, N

    2015-01-01

    Motivated by dualistic considerations of the reality of quark condensation in quantum chromodynamics, and the connections of supergravity to the exotic physics of string and M-theory, in this thesis we investigate the dynamical breaking of local supersymmetry via gravitino condensation. We firstly demonstrate non-perturbative gravitino mass generation via this mechanism in flat spacetime, and from this derive the condensate mode wavefunction renormalisation. By then calculating the full canonically normalised one-loop effective potential for the condensate mode about a de Sitter background, we demonstrate that, contrary to claims in the literature, this process may both occur and function in a phenomenologically viable manner. In particular, we find that outside of certain unfortunate gauge choices, the stability of the condensate is intimately tied via gravitational degrees of freedom to the sign of the tree-level cosmological constant. Furthermore, we find that the energy density liberated may provide the n...

  18. When does lasing become a condensation phenomenon?

    CERN Document Server

    Fischer, Baruch

    2012-01-01

    We present a generic classical light condensation (LC) phenomenon in linear photonic mode systems, such as cw laser cavities, in a noisy environment (spontaneous emission, etc.), based on weighting the modes in a loss-gain scale rather than in photon energy. It is characterized by a sharp transition from multi- to single-mode oscillation. The study uses a linear multivariate Langevin formulation which gives a mode occupation hierarchy that functions like Bose-Einstein statistics. We find that condensation occurs when the spectral filtering has near the lowest loss mode a power law dependence with exponent smaller than 1. We then discuss how and when condensation occurs in photon systems, how it relates to lasing, and the difficulties to observe regular photon Bose-Einstein condensation (BEC) in laser cavities. We raise the possibility that recent experiments on photon condensation in optical cavities fall in a classical LC or lasing category rather than being a thermal-quantum BEC phenomenon.

  19. Flow cytometric detection of aberrant chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.W.; Lucas, J.; Yu, L.C.; Langlois, R.

    1983-05-11

    This report describes the quantification of chromosomal aberrations by flow cytometry. Both homogeneously and heterogeneously occurring chromosome aberrations were studied. Homogeneously occurring aberrations were noted in chromosomes isolated from human colon carcinoma (LoVo) cells, stained with Hoechst 33258 and chromomycin A3 and analyzed using dual beam flow cytometry. The resulting bivariate flow karyotype showed a homogeneously occurring marker chromosome of intermediate size. Heterogeneously occurring aberrations were quantified by slit-scan flow cytometry in chromosomes isolated from control and irradiated Chinese hamster cells and stained with propidium iodide. Heterogeneously occurring dicentric chromosomes were detected by their shapes (two centrometers). The frequencies of such chromosomes estimated by slit-scan flow cytometry correlated well with the frequencies determined by visual microscopy.

  20. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate...... method enabled us to start the analysis on the distribution of various chromosomal loci inside slowly growing cells. With the actual counting and measuring no longer being any problem we could easily analyze 14 loci distributed on the E.coli chromosome. More than 15.000 cells were analyzed in total...... the new system, which is based on the pMT1 par system from Yersenia pestis, we labeled loci on opposite sides of the E.coli chromosome simultaneously and were able to show that the E.coli chromosome is organized with one chromosomal arm in each cell half. This astounding result is described in Paper III...

  1. Mitosis. Microtubule detyrosination guides chromosomes during mitosis.

    Science.gov (United States)

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K; Magiera, Maria M; Zaytsev, Anatoly V; Pereira, Ana L; Janke, Carsten; Grishchuk, Ekaterina L; Maiato, Helder

    2015-05-15

    Before chromosomes segregate into daughter cells, they align at the mitotic spindle equator, a process known as chromosome congression. Centromere-associated protein E (CENP-E)/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically toward the equator. We found that congression of pole-proximal chromosomes depended on specific posttranslational detyrosination of spindle microtubules that point to the equator. In vitro reconstitution experiments demonstrated that CENP-E-dependent transport was strongly enhanced on detyrosinated microtubules. Blocking tubulin tyrosination in cells caused ubiquitous detyrosination of spindle microtubules, and CENP-E transported chromosomes away from spindle poles in random directions. Thus, CENP-E-driven chromosome congression is guided by microtubule detyrosination. PMID:25908662

  2. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    Directory of Open Access Journals (Sweden)

    Daniela Mierla

    2012-06-01

    Full Text Available Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, karyotype analysis by G-banding was performed from peripheral blood in 967 women infertility. Results: Chromosomal abnormalities were found to 79 women (8,17%. The percentage of chromosomal abnormalities in the studied population correlates with the data in the literature. Chromosomal abnormalities could play the important role in etiology of infertility and are more frequently detected in this group of patients compared to general population. In the infertile couples balanced chromosomal abnormalities are the main cause of spontaneous abortions.

  3. A dominant negative mutant of TLK1 causes chromosome missegregation and aneuploidy in normal breast epithelial cells

    Directory of Open Access Journals (Sweden)

    Williams Briana

    2003-10-01

    Full Text Available Abstract Background In Arabidopsis thaliana, the gene Tousled encodes a protein kinase of unknown function, but mutations in the gene lead to flowering and leaf morphology defects. We have recently cloned a mammalian Tousled-Like Kinase (TLK1B and found that it phosphorylates specifically histone H3, in vitro and in vivo. We now report the effects that overexpression of a kinase-dead mutant of TLK1B mediates in a normal diploid cell line. Results Expression of a kinase-dead mutant resulted in reduction of phosphorylated histone H3, which could have consequences in mitotic segregation of chromosomes. When analyzed by FACS and microscopy, these cells displayed high chromosome number instability and aneuploidy. This phenomenon was accompanied by less condensed chromosomes at mitosis; failure of a number of chromosomes to align properly on the metaphase plate; failure of some chromosomes to attach to microtubules; and the occasional presentation of two bipolar spindles. We also used a different method (siRNA to reduce the level of endogenous TLK1, but in this case, the main result was a strong block of cell cycle progression suggesting that TLK1 may also play a role in progression from G1. This block in S phase progression could also offer a different explanation of some of the later mitotic defects. Conclusions TLK1 has a function important for proper chromosome segregation and maintenance of diploid cells at mitosis in mammalian cells that could be mediated by reduced phosphorylation of histone H3 and condensation of chromosomes, although other explanations to the phenotype are possible.

  4. Post-zygotic breakage of a dicentric chromosome results in mosaicism for a telocentric 9p marker chromosome in a boy with developmental delay.

    Science.gov (United States)

    Pedurupillay, C R J; Misceo, D; Gamage, T H; Dissanayake, V H W; Frengen, E

    2014-01-01

    Chromosomal rearrangements resulting in an inverted duplication and a terminal deletion (inv dup del) can occur due to three known mechanisms, two of them resulting in a normal copy region between the duplicated regions. These mechanisms involve the formation of a dicentric chromosome, which undergo breakage during cell division resulting in cells with either an inverted duplication and deletion or a terminal deletion. We describe a mosaic 3 year old patient with two cell lines carrying a chromosome 9p deletion where one of the cell lines contains an additional telocentric marker chromosome. Our patient is mosaic for the product of a double breakage of a dicentric chromosome including a centric fission. Mosaicism involving different rearrangements of the same chromosome is rare and suggests an early mitotic breakage event. Chr9p terminal deletions associated with duplications have previously been reported in 11 patients. We compare the clinical features of all 12 patients including the patient that we report here. To the best to our knowledge this is a first case reported where the double breakage occurred in the dicentric derivative chromosome 9.

  5. Chromosomal instability determines taxane response

    DEFF Research Database (Denmark)

    Swanton, C.; Nicke, B.; Schuett, M.;

    2009-01-01

    -positive breast cancer and occurs frequently in basal-like and Her2-positive cases. In diploid cells, but not in chromosomally unstable cells, paclitaxel causes repression of CIN-survival genes, followed by cell death. In the OV01 ovarian cancer clinical trial, a high level of CIN was associated with taxane...... chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells. Overexpression of these "CIN-survival'' genes is associated with poor outcome in estrogen receptor...... resistance but carboplatin sensitivity, indicating that CIN may determine MTS response in vivo. Thus, pretherapeutic assessment of CIN may optimize treatment stratification and clinical trial design using these agents....

  6. Microdissection and chromosome painting of the alien chromosome in an addition line of wheat-Thinopyrum intermedium

    Science.gov (United States)

    The chromosome painting is an efficient tool for chromosome research. However, plant chromosome painting is relatively underdeveloped. In this study, chromosome painting was developed and used to identify alien chromosomes in TAi-27, a wheat-Thinopyrum intermedium addition line, and chromosomes of...

  7. Chromosomal instability determines taxane response

    OpenAIRE

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C.; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang

    2009-01-01

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells....

  8. Environmental pollution, chromosomes, and health

    Science.gov (United States)

    Bell, Peter M.

    In mid-May, 1980, President Carter declared a state of emergency at the Love Canal area, near Niagara Falls, New York. The reason for this was for the U.S. to underwrite the relocation costs ($3-5 million) of some 2500 residents who, according to a report by the EPA (Environmental Protection Agency) may have suffered damaged chromosomes. These injuries were apparently caused by contact with toxic wastes that had been dumped in the area in the years prior to development for housing.That the toxic compounds exist in the Love Canal and Niagara Falls subsurface zones, including public water supplies, appears to be established fact. That the residents of the Love Canal area suffered chromosomal damage may be established fact as well. Whether or not these two findings can be linked to ill health of the residents is another matter. Recently, the EPA report has been described as having ‘close to zero scientific significance,’ and has been ‘discredited’(Science, 208, 123a, 1980). The reasons for this disparity go beyond differences of opinion, beyond possible inadequacies of the EPA study, and even beyond problems that probably will arise from future studies, including those now in the planning stages. The problem is that even if victims have easily recognizable injuries from toxic substances (injury that apparently has not occurred to Love Canal residents), medical science usually cannot show a causal relationship. Even chromosomal damage is, at best, difficult to interpret. In ideal studies of significant populations and control groups, the association of toxic chemical to chromosome damage and to cancer and birth defects is indirect and, up to now, has been shown to have little or no significance to an individual member of the exposed population.

  9. GSK-3 inhibitors induce chromosome instability

    Directory of Open Access Journals (Sweden)

    Staples Oliver D

    2007-08-01

    Full Text Available Abstract Background Several mechanisms operate during mitosis to ensure accurate chromosome segregation. However, during tumour evolution these mechanisms go awry resulting in chromosome instability. While several lines of evidence suggest that mutations in adenomatous polyposis coli (APC may promote chromosome instability, at least in colon cancer, the underlying mechanisms remain unclear. Here, we turn our attention to GSK-3 – a protein kinase, which in concert with APC, targets β-catenin for proteolysis – and ask whether GSK-3 is required for accurate chromosome segregation. Results To probe the role of GSK-3 in mitosis, we inhibited GSK-3 kinase activity in cells using a panel of small molecule inhibitors, including SB-415286, AR-A014418, 1-Azakenpaullone and CHIR99021. Analysis of synchronised HeLa cells shows that GSK-3 inhibitors do not prevent G1/S progression or cell division. They do, however, significantly delay mitotic exit, largely because inhibitor-treated cells have difficulty aligning all their chromosomes. Although bipolar spindles form and the majority of chromosomes biorient, one or more chromosomes often remain mono-oriented near the spindle poles. Despite a prolonged mitotic delay, anaphase frequently initiates without the last chromosome aligning, resulting in chromosome non-disjunction. To rule out the possibility of "off-target" effects, we also used RNA interference to selectively repress GSK-3β. Cells deficient for GSK-3β exhibit a similar chromosome alignment defect, with chromosomes clustered near the spindle poles. GSK-3β repression also results in cells accumulating micronuclei, a hallmark of chromosome missegregation. Conclusion Thus, not only do our observations indicate a role for GSK-3 in accurate chromosome segregation, but they also raise the possibility that, if used as therapeutic agents, GSK-3 inhibitors may induce unwanted side effects by inducing chromosome instability.

  10. Glom is a novel mitochondrial DNA packaging protein in Physarum polycephalum and causes intense chromatin condensation without suppressing DNA functions.

    Science.gov (United States)

    Sasaki, Narie; Kuroiwa, Haruko; Nishitani, Chikako; Takano, Hiroyoshi; Higashiyama, Tetsuya; Kobayashi, Tamaki; Shirai, Yuki; Sakai, Atsushi; Kawano, Shigeyuki; Murakami-Murofushi, Kimiko; Kuroiwa, Tsuneyoshi

    2003-12-01

    Mitochondrial DNA (mtDNA) is packed into highly organized structures called mitochondrial nucleoids (mt-nucleoids). To understand the organization of mtDNA and the overall regulation of its genetic activity within the mt-nucleoids, we identified and characterized a novel mtDNA packaging protein, termed Glom (a protein inducing agglomeration of mitochondrial chromosome), from highly condensed mt-nucleoids of the true slime mold, Physarum polycephalum. This protein could bind to the entire mtDNA and package mtDNA into a highly condensed state in vitro. Immunostaining analysis showed that Glom specifically localized throughout the mt-nucleoid. Deduced amino acid sequence revealed that Glom has a lysine-rich region with proline-rich domain in the N-terminal half and two HMG boxes in C-terminal half. Deletion analysis of Glom revealed that the lysine-rich region was sufficient for the intense mtDNA condensation in vitro. When the recombinant Glom proteins containing the lysine-rich region were expressed in Escherichia coli, the condensed nucleoid structures were observed in E. coli. Such in vivo condensation did not interfere with transcription or replication of E. coli chromosome and the proline-rich domain was essential to keep those genetic activities. The expression of Glom also complemented the E. coli mutant lacking the bacterial histone-like protein HU and the HMG-boxes region of Glom was important for the complementation. Our results suggest that Glom is a new mitochondrial histone-like protein having a property to cause intense DNA condensation without suppressing DNA functions. PMID:12960433

  11. Chromosome aberration assays in Allium

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  12. Chromosome rearrangements and transposable elements.

    Science.gov (United States)

    Lonnig, Wolf-Ekkehard; Saedler, Heinz

    2002-01-01

    There has been limited corroboration to date for McClintock's vision of gene regulation by transposable elements (TEs), although her proposition on the origin of species by TE-induced complex chromosome reorganizations in combination with gene mutations, i.e., the involvement of both factors in relatively sudden formations of species in many plant and animal genera, has been more promising. Moreover, resolution is in sight for several seemingly contradictory phenomena such as the endless reshuffling of chromosome structures and gene sequences versus synteny and the constancy of living fossils (or stasis in general). Recent wide-ranging investigations have confirmed and enlarged the number of earlier cases of TE target site selection (hot spots for TE integration), implying preestablished rather than accidental chromosome rearrangements for nonhomologous recombination of host DNA. The possibility of a partly predetermined generation of biodiversity and new species is discussed. The views of several leading transposon experts on the rather abrupt origin of new species have not been synthesized into the macroevolutionary theory of the punctuated equilibrium school of paleontology inferred from thoroughly consistent features of the fossil record. PMID:12429698

  13. Chromosome locations of genes encoding human signal transduction adapter proteins, Nck (NCK), Shc (SHC1), and Grb2 (GRB2)

    DEFF Research Database (Denmark)

    Huebner, K; Kastury, K; Druck, T;

    1994-01-01

    Abnormalities due to chromosomal aberration or point mutation in gene products of growth factor receptors or in ras gene products, which lie on the same signaling pathway, can cause disease in animals and humans. Thus, it can be important to determine chromosomal map positions of genes encoding "...

  14. Comparative Chromosome Map and Heterochromatin Features of the Gray Whale Karyotype (Cetacea).

    Science.gov (United States)

    Kulemzina, Anastasia I; Proskuryakova, Anastasia A; Beklemisheva, Violetta R; Lemskaya, Natalia A; Perelman, Polina L; Graphodatsky, Alexander S

    2016-01-01

    Cetacean karyotypes possess exceptionally stable diploid numbers and highly conserved chromosomes. To date, only toothed whales (Odontoceti) have been analyzed by comparative chromosome painting. Here, we studied the karyotype of a representative of baleen whales, the gray whale (Eschrichtius robustus, Mysticeti), by Zoo-FISH with dromedary camel and human chromosome-specific probes. We confirmed a high degree of karyotype conservation and found an identical order of syntenic segments in both branches of cetaceans. Yet, whale chromosomes harbor variable heterochromatic regions constituting up to a third of the genome due to the presence of several types of repeats. To investigate the cause of this variability, several classes of repeated DNA sequences were mapped onto chromosomes of whale species from both Mysticeti and Odontoceti. We uncovered extensive intrapopulation variability in the size of heterochromatic blocks present in homologous chromosomes among 3 individuals of the gray whale by 2-step differential chromosome staining. We show that some of the heteromorphisms observed in the gray whale karyotype are due to distinct amplification of a complex of common cetacean repeat and heavy satellite repeat on homologous autosomes. Furthermore, we demonstrate localization of the telomeric repeat in the heterochromatin of both gray and pilot whale (Globicephala melas, Odontoceti). Heterochromatic blocks in the pilot whale represent a composite of telomeric and common repeats, while heavy satellite repeat is lacking in the toothed whale consistent with previous studies.

  15. Comparative Chromosome Map and Heterochromatin Features of the Gray Whale Karyotype (Cetacea).

    Science.gov (United States)

    Kulemzina, Anastasia I; Proskuryakova, Anastasia A; Beklemisheva, Violetta R; Lemskaya, Natalia A; Perelman, Polina L; Graphodatsky, Alexander S

    2016-01-01

    Cetacean karyotypes possess exceptionally stable diploid numbers and highly conserved chromosomes. To date, only toothed whales (Odontoceti) have been analyzed by comparative chromosome painting. Here, we studied the karyotype of a representative of baleen whales, the gray whale (Eschrichtius robustus, Mysticeti), by Zoo-FISH with dromedary camel and human chromosome-specific probes. We confirmed a high degree of karyotype conservation and found an identical order of syntenic segments in both branches of cetaceans. Yet, whale chromosomes harbor variable heterochromatic regions constituting up to a third of the genome due to the presence of several types of repeats. To investigate the cause of this variability, several classes of repeated DNA sequences were mapped onto chromosomes of whale species from both Mysticeti and Odontoceti. We uncovered extensive intrapopulation variability in the size of heterochromatic blocks present in homologous chromosomes among 3 individuals of the gray whale by 2-step differential chromosome staining. We show that some of the heteromorphisms observed in the gray whale karyotype are due to distinct amplification of a complex of common cetacean repeat and heavy satellite repeat on homologous autosomes. Furthermore, we demonstrate localization of the telomeric repeat in the heterochromatin of both gray and pilot whale (Globicephala melas, Odontoceti). Heterochromatic blocks in the pilot whale represent a composite of telomeric and common repeats, while heavy satellite repeat is lacking in the toothed whale consistent with previous studies. PMID:27088853

  16. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae).

    Science.gov (United States)

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  17. Chromosomal divergence and evolutionary inferences in Rhodniini based on the chromosomal location of ribosomal genes

    Directory of Open Access Journals (Sweden)

    Sebastian Pita

    2013-05-01

    Full Text Available In this study, we used fluorescence in situ hybridisation to determine the chromosomal location of 45S rDNA clusters in 10 species of the tribe Rhodniini (Hemiptera: Reduviidae: Triatominae. The results showed striking inter and intraspecific variability, with the location of the rDNA clusters restricted to sex chromosomes with two patterns: either on one (X chromosome or both sex chromosomes (X and Y chromosomes. This variation occurs within a genus that has an unchanging diploid chromosome number (2n = 22, including 20 autosomes and 2 sex chromosomes and a similar chromosome size and genomic DNA content, reflecting a genome dynamic not revealed by these chromosome traits. The rDNA variation in closely related species and the intraspecific polymorphism in Rhodnius ecuadoriensis suggested that the chromosomal position of rDNA clusters might be a useful marker to identify recently diverged species or populations. We discuss the ancestral position of ribosomal genes in the tribe Rhodniini and the possible mechanisms involved in the variation of the rDNA clusters, including the loss of rDNA loci on the Y chromosome, transposition and ectopic pairing. The last two processes involve chromosomal exchanges between both sex chromosomes, in contrast to the widely accepted idea that the achiasmatic sex chromosomes of Heteroptera do not interchange sequences.

  18. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    Science.gov (United States)

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Abstract B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  19. Phosphorylation of HPV-16 E2 at serine 243 enables binding to Brd4 and mitotic chromosomes.

    Directory of Open Access Journals (Sweden)

    Szu-Wei Chang

    Full Text Available The papillomavirus E2 protein is involved in the maintenance of persistent infection and known to bind either to cellular factors or directly to mitotic chromosomes in order to partition the viral genome into the daughter cells. However, how the HPV-16 E2 protein acts to facilitate partitioning of the viral genome remains unclear. In this study, we found that serine 243 of HPV-16 E2, located in the hinge region, is crucial for chromosome binding during mitosis. Bromodomain protein 4 (Brd4 has been identified as a cellular binding target through which the E2 protein of bovine papillomavirus type 1 (BPV-1 tethers the viral genome to mitotic chromosomes. Mutation analysis showed that, when the residue serine 243 was substituted by glutamic acid or aspartic acid, whose negative charges mimic the effect of constitutive phosphorylation, the protein still can interact with Brd4 and colocalize with Brd4 in condensed metaphase and anaphase chromosomes. However, substitution by the polar uncharged residues asparagine or glutamine abrogated Brd4 and mitotic chromosome binding. Moreover, following treatment with the inhibitor JQ1 to release Brd4 from the chromosomes, Brd4 and E2 formed punctate foci separate from the chromosomes, further supporting the hypothesis that the association of the HPV-16 E2 protein with the chromosomes is Brd4-dependent. In addition, the S243A E2 protein has a shorter half-life than the wild type, indicating that phosphorylation of the HPV-16 E2 protein at serine 243 also increases its half-life. Thus, phosphorylation of serine 243 in the hinge region of HPV-16 E2 is essential for interaction with Brd4 and required for host chromosome binding.

  20. Mechanisms of chromosomal rearrangement in the human genome

    OpenAIRE

    Lieber Michael R; Tsai Albert G

    2010-01-01

    Abstract Many human cancers are associated with characteristic chromosomal rearrangements, especially hematopoietic cancers such as leukemias and lymphomas. The first and most critical step in the rearrangement process is the induction of two DNA double-strand breaks (DSB). In all cases, at least one of the two DSBs is generated by a pathologic process, such as (1) randomly-positioned breaks due to ionizing radiation, free radical oxidative damage, or spontaneous hydrolysis; (2) breaks associ...

  1. The genus Rubus in South Africa. II. Meiotic chromosome behaviour

    Directory of Open Access Journals (Sweden)

    J. J. Spies

    1984-12-01

    Full Text Available Meiotic chromosome behaviour in the genus Rubus is relatively normal Polyploidy occurs in both South African subgenera, i.e. Eubatus and Idaeobatus. The subgenus Eubatus contains plants tending mostly towards autoploidy. whereas the subgenus  Idaeobatus varies from autoploid, through segmental alloploid to alloploid. It is concluded that this apparent difference might be due to the study of a statistically insufficient number of plants and that alloploidy originated from imersubgeneric hybridization.

  2. Reduced Effective Model for Condensation in Slender Tubes with Rotational Symmetry, Obtained by Generalized Dimensional Analysis

    CERN Document Server

    Dziubek, Andrea

    2011-01-01

    Experimental results for condensation in compact heat exchangers show that the heat transfer due to condensation is significantly better compared to classical heat exchangers, especially when using R134a instead of water as the refrigerant. This suggests that surface tension plays a role. Using generalized dimensional analysis we derive reduced model equations and jump conditions for condensation in a vertical tube with cylindrical cross section. Based on this model we derive a single ordinary differential equation for the thickness of the condensate film as function of the tube axis. Our model agrees well with commonly used models from existing literature. It is based on the physical dimensions of the problem and has greater geometrical flexibility.

  3. Bistable behavior of a two-mode Bose–Einstein condensate in an optical cavity

    International Nuclear Information System (INIS)

    We consider a two-component Bose–Einstein condensate in a one-dimensional optical cavity. Specifically, the condensate atoms are taken to be in two degenerate modes due to their internal hyperfine spin degrees of freedom and they are coupled to the cavity field and an external transverse laser field in a Raman scheme. A parallel laser also excites the cavity mode. When the pump laser is far detuned from its resonance atomic transition frequency, an effective nonlinear optical model of the cavity–condensate system is developed under the discrete mode approximation (DMA), while matter–field coupling has been considered beyond the rotating wave approximation. By analytical and numerical solutions of the nonlinear dynamical equations, we examine the mean cavity field and population difference (magnetization) of the condensate modes. The stationary solutions of both the mean cavity field and normalized magnetization demonstrate bistable behavior under certain conditions for the laser pump intensity and matter–field coupling strength. (paper)

  4. Marfan syndrome with a complex chromosomal rearrangement including deletion of the FBN1 gene

    Directory of Open Access Journals (Sweden)

    Colovati Mileny ES

    2012-01-01

    Full Text Available Abstract Background The majority of Marfan syndrome (MFS cases is caused by mutations in the fibrillin-1 gene (FBN1, mapped to chromosome 15q21.1. Only few reports on deletions including the whole FBN1 gene, detected by molecular cytogenetic techniques, were found in literature. Results We report here on a female patient with clinical symptoms of the MFS spectrum plus craniostenosis, hypothyroidism and intellectual deficiency who presents a 1.9 Mb deletion, including the FBN1 gene and a complex rearrangement with eight breakpoints involving chromosomes 6, 12 and 15. Discussion This is the first report of MFS with a complex chromosome rearrangement involving a deletion of FBN1 and contiguous genes. In addition to the typical clinical findings of the Marfan syndrome due to FBN1 gene haploinsufficiency, the patient presents features which may be due to the other gene deletions and possibly to the complex chromosome rearrangement.

  5. The presence of synaptic and chromosome disjunction mutants in Cenchrus ciliaris (Poaceae: Paniceae

    Directory of Open Access Journals (Sweden)

    N. C. Visser

    1999-12-01

    Full Text Available Synaptic mutants are present in  Cenchrus ciliaris L This species, due to the presence of linear bivalents and occasion­al trivalents and quadrivalents, is an intermediate desynaptic species. In addition, geographical distribution and environmental factors, such as high temperatures and low humidity, could also have had an influence on the desynapsis observed.The disjunction of chromosomes during anaphase I was mostly abnormal in this desynaptic species. Precocious disjunction of chromosomes into chromatids occurred during anaphase I Due to the high incidence of this chromosome abnormality, a mutant gene,  'pc'  responsible for the disjunction of chromosomes, must be present. The absence of cytokinesis in one specimen indicates a recessive mutant gene,  'va' to be active in this species.

  6. Recombinant chromosome 9 possibly derived from breakage and reunion of sister chromatids within a paracentric inversion loop.

    Science.gov (United States)

    Phelan, M C; Stevenson, R E; Anderson, E V

    1993-05-15

    Chromosomally unbalanced offspring resulting from the recombination of parental paracentric inversions are uncommon. We report on a 20-month-old boy with a partial duplication of 9p due to the recombination of a paternal paracentric inversion. The patient's recombinant chromosome was designated rec(9)(p13-->p24::p12-->p24::p12-->qter). The patient's father and paternal aunt have a paracentric inversion of chromosome 9:inv(9)(p13p24). Although several mechanisms have been proposed to explain the chromosome imbalance generated from paracentric inversions, none of the previously described mechanisms can account for the structure of the recombinant chromosome observed in the propositus. We propose an unusual mechanism of formation involving breakage and unequal reunion of sister chromatids within the inversion loop to explain the structure of the patient's recombinant chromosome. PMID:8488876

  7. Chromosomal mosaicism of extraembryonic cells detected by prenatal diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Zolotukhina, T.V.; Shilova, N.V. [Institute of Clinical Genetics, Moscow (Russian Federation)

    1995-09-01

    Data on detection of chromosomal mosaicism in amniotic cells and chorionic villi obtained by prenatal cytogenetic diagnosis are presented. The frequency of chromosomal mosaicism in preparations of amniotic fluid cell culture was 2.6% (6 out of 226), and that in {open_quotes}direct{close_quotes} villus preparations was 1.6% (13 out of 774). The necessity to perform an additional analysis of other fetal cells or neonatal lymphocytes to specify the diagnosis was shown. The analysis of the outcome of pregnancies during which chromosomal mosaicism in the extraembryonic cells was detected indicates that these women form a high-risk group, both genetically and obstetrically; in only 8 out of 19 cases did pregnancies end in normal deliveries at term; in three cases, spontaneous abortions occurred at 16-31 weeks of gestation; in three cases, the pregnancies were terminated due to fetal chromosomal aberrations in nonmosaic form; the outcome of pregnancy in five cases was preterm delivery of an underweight newborn. 26 refs., 1 tab.

  8. Phenotypic correlations in a patient with ring chromosome 22

    Directory of Open Access Journals (Sweden)

    Demirhan Osman

    2010-01-01

    Full Text Available Ring chromosome 22, a rare cytogenetic anomaly, has been described in over 60 cases in the medical literature. The aim of this report was to present a case carrying ring chromosome 22, and her family. It is a case report of a patient presented at Medical Faculty of Ηukurova University in Turkey. An 8-year-old girl with ring chromosome 22 and her family were evaluated cytogenetically and clinically. A chromosome analysis of the proband revealed a de novo 46,XX,r(22(p11.2;q13 karyotype. Our subject demonstrated the prominent features of this syndrome including profound mental retardation, language impairment, dysmorphic features, lack of speech, hyperactivity, and behavioral disorders. There is lack of consistency between the physical abnormalities that we observed in our subject and those observed for such patients in the literature. The wide range of manifestations observed in patients with this cytogenetic alteration is probably due to size differences in the deleted region.

  9. Hexavalent chromium induces chromosome instability in human urothelial cells.

    Science.gov (United States)

    Wise, Sandra S; Holmes, Amie L; Liou, Louis; Adam, Rosalyn M; Wise, John Pierce

    2016-04-01

    Numerous metals are well-known human bladder carcinogens. Despite the significant occupational and public health concern of metals and bladder cancer, the carcinogenic mechanisms remain largely unknown. Chromium, in particular, is a metal of concern as incidences of bladder cancer have been found elevated in chromate workers, and there is an increasing concern for patients with metal hip implants. However, the impact of hexavalent chromium (Cr(VI)) on bladder cells has not been studied. We compared chromate toxicity in two bladder cell lines; primary human urothelial cells and hTERT-immortalized human urothelial cells. Cr(VI) induced a concentration- and time-dependent increase in chromosome damage in both cell lines, with the hTERT-immortalized cells exhibiting more chromosome damage than the primary cells. Chronic exposure to Cr(VI) also induced a concentration-dependent increase in aneuploid metaphases in both cell lines which was not observed after a 24h exposure. Aneuploidy induction was higher in the hTERT-immortalized cells. When we correct for uptake, Cr(VI) induces a similar amount of chromosome damage and aneuploidy suggesting that the differences in Cr(VI) sensitivity between the two cells lines were due to differences in uptake. The increase in chromosome instability after chronic chromate treatment suggests this may be a mechanism for chromate-induced bladder cancer, specifically, and may be a mechanism for metal-induced bladder cancer, in general. PMID:26908176

  10. Dispensing fuel with aspiration of condensed vapors

    Energy Technology Data Exchange (ETDEWEB)

    Butkovich, M.S.; Strock, D.J.

    1993-08-10

    A vapor recovery process is described, comprising the steps of: fueling a motor vehicle with gasoline by discharging gasoline into a fill opening or filler pipe of a tank of said vehicle through a fuel outlet conduit of a nozzle; emitting gasoline vapors from said tank during said fueling; substantially collecting said vapors during said fueling with a vapor return conduit of said nozzle and passing said vapors through said vapor return conduit in counter current flow relationship to said discharging gasoline in said fuel conduit; conveying said vapors from said vapor return conduit to a vapor return hose; at least some of said vapors condensing to form condensate in said vapor return hose; substantially removing said condensate from said vapor return hose during said fueling with a condensate pickup tube from said nozzle by passing said condensate through said condensate pickup tube in counter current flow relationship to said conveying vapors in said vapor return hose; sensing the presence of gasoline with a liquid sensing tube in said vapor return conduit of said nozzle between inner and outer spouts of said nozzle to detect when said tank of said vehicle is filled with said fuel conduit being within the inner spout of said nozzle; and automatically shutting off said fueling and condensate removing when said liquid sensing tube detects when said tank of said vehicle is filled and fuel enters said vapor return conduit.

  11. Enhancing dropwise condensation through bioinspired wettability patterning.

    Science.gov (United States)

    Ghosh, Aritra; Beaini, Sara; Zhang, Bong June; Ganguly, Ranjan; Megaridis, Constantine M

    2014-11-01

    Dropwise condensation (DWC) heat transfer depends strongly on the maximum diameter (Dmax) of condensate droplets departing from the condenser surface. This study presents a facile technique implemented to gain control of Dmax in DWC within vapor/air atmospheres. We demonstrate how this approach can enhance the corresponding heat transfer rate by harnessing the capillary forces in the removal of the condensate from the surface. We examine various hydrophilic-superhydrophilic patterns, which, respectively, sustain and combine DWC and filmwise condensation on the substrate. The material system uses laser-patterned masking and chemical etching to achieve the desired wettability contrast and does not employ any hydrophobizing agent. By applying alternating straight parallel strips of hydrophilic (contact angle ∼78°) mirror-finish aluminum and superhydrophilic regions (etched aluminum) on the condensing surface, we show that the average maximum droplet size on the less-wettable domains is nearly 42% of the width of the corresponding strips. An overall improvement in the condensate collection rate, up to 19% (as compared to the control case of DWC on mirror-finish aluminum) was achieved by using an interdigitated superhydrophilic track pattern (on the mirror-finish hydrophilic surface) inspired by the vein network of plant leaves. The bioinspired interdigitated pattern is found to outperform the straight hydrophilic-superhydrophilic pattern design, particularly under higher humidity conditions in the presence of noncondensable gases (NCG), a condition that is more challenging for maintaining sustained DWC.

  12. Dynamics of condensation on lubricant impregnated surfaces

    Science.gov (United States)

    Anand, Sushant; Paxson, Adam; Rykaczewski, Konrad; Beysens, Daniel; Varanasi, Kripa

    2013-03-01

    Replacing the filmwise condensation mode with dropwise condensation promises large improvements in heat transfer that will lead to large cost savings in material, water consumption and decreased size of the systems. In this regards, use of superhydrophobic surfaces fabricated by texturing surfaces with nano/microstructures has been shown to lead decrease in contact line pinning of millimetric drops resulting in fast shedding. However, these useful properties are lost during condensation where droplets that nucleate within texture grow by virtue of condensation to large sized droplets while still adhering to the surface. Recently we have shown that liquid impregnated surfaces can overcome many limitations of conventional superhydrophobic surfaces during condensation. Here we discuss aspects related to condensation on lubricant surfaces, such as behavior of growing droplets. We compare the characteristics of droplets condensing on these surfaces with their behavior on conventional un-impregnated superhydrophobic surfaces and show how use of lubricant impregnated surfaces may lead to large enhancement in heat transfer and energy efficiencies.

  13. Boson condensation in topologically ordered quantum liquids

    Science.gov (United States)

    Neupert, Titus; He, Huan; von Keyserlingk, Curt; Sierra, Germán; Bernevig, B. Andrei

    2016-03-01

    Boson condensation in topological quantum field theories (TQFT) has been previously investigated through the formalism of Frobenius algebras and the use of vertex lifting coefficients. While general, this formalism is physically opaque and computationally arduous: analyses of TQFT condensation are practically performed on a case by case basis and for very simple theories only, mostly not using the Frobenius algebra formalism. In this paper, we provide a way of treating boson condensation that is computationally efficient. With a minimal set of physical assumptions, such as commutativity of lifting and the definition of confined particles, we can prove a number of theorems linking Boson condensation in TQFT with chiral algebra extensions, and with the factorization of completely positive matrices over Z+. We present numerically efficient ways of obtaining a condensed theory fusion algebra and S matrices; and we then use our formalism to prove several theorems for the S and T matrices of simple current condensation and of theories which upon condensation result in a low number of confined particles. We also show that our formalism easily reproduces results existent in the mathematical literature such as the noncondensability of five and ten layers of the Fibonacci TQFT.

  14. Direct contact condensation in packed beds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi; Klausner, James F.; Mei, Renwei; Knight, Jessica [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611 (United States)

    2006-12-15

    A diffusion driven desalination process was recently described where a very effective direct contact condenser with a packed bed is used to condense water vapor out of an air/vapor mixture. A laboratory scale direct contact condenser has been fabricated as a twin tower structure with two stages, co-current and countercurrent. Experiments have been operated in each stage with respective saturated air inlet temperatures of 36, 40 and 43{sup o}C. The temperature and humidity data have been collected at the inlet and exit of the packed bed for different water to air mass flow ratios that vary between 0 and 2.5. A one-dimensional model based on conservation principles has been developed, which predicts the variation of temperature, humidity, and condensation rate through the condenser stages. Agreement between the model and experiments is very good. It is observed that the countercurrent flow stage condensation effectiveness is significantly higher than that for the co-current stage. The condensation heat and mass transfer rates were found to decrease when water blockages occur within the packed bed. Using high-speed digital cinematography, it was observed that this problem can occur at any operating condition, and is dependent on the packing surface wetting characteristics. This observation is used to explain the requirement for two different empirical constants, depending on packing diameter, suggested by Onda for the air side mass transfer coefficient correlation. (author)

  15. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  16. The peripheral chromosome scaffold, a novel structural component of mitotic chromosomes.

    Science.gov (United States)

    Sheval, Eugene V; Polyakov, Vladimir Y

    2008-06-01

    Using an original high-salt extraction protocol, we observed a novel chromosome substructure, referred to as the peripheral chromosome scaffold. This chromosome domain contained the perichromosomal layer proteins pKi-67, B23/nucleophosmin and fibrillarin, but no DNA fragments (i.e., the loop domain bases were not associated with the peripheral scaffold). Modern models of chromosome organization do not predict the existence of a peripheral chromosome scaffold domain, and thus our observations have conceptual implications for understanding chromosome architecture. PMID:18337132

  17. Gravitational Condensation of Atmospheric Water Vapor

    OpenAIRE

    De Aquino, Fran

    2015-01-01

    Devices that collect water from the atmospheric air using condensation are well-known. They operate in a manner very similar to that of a dehumidifier: air is passed through a cooled coil, making water to condense. This is the most common technology in use. Here, we present a device that can collect a large amount of water (more than 1m 3 /s) from the atmospheric air using gravitational condensation. Another novelty of this device is that it consumes little electricity. In addition, the new t...

  18. Quark Virtuality and QCD Vacuum Condensates

    Institute of Scientific and Technical Information of China (English)

    ZHOU Li-Juan; MA Wei-Xing

    2004-01-01

    @@ Based on the Dyson-Schwinger equations (DSEs) in the ‘rainbow' approximation, we investigate the quark virtuality in the vacuum state and quantum-chromodynamics (QCD) vacuum condensates. In particular, we calculate the local quark vacuum condensate and quark-gluon mixed condensates, and then the virtuality of quark. The calculated quark virtualities are λ2u,d = 0.7 GeV2 for u, d quarks, and 2s 1.6 GeV2 for s quark.Our theoretical predictions are consistent with empirical values used in QCD sum rules, and also fit to lattice QCD predictions.

  19. The Complete Mechanism of an Aldol Condensation.

    Science.gov (United States)

    Perrin, Charles L; Chang, Kuei-Lin

    2016-07-01

    Although aldol condensation is one of the most important organic reactions, capable of forming new C-C bonds, its mechanism has never been fully established. We now conclude that the rate-limiting step in the base-catalyzed aldol condensation of benzaldehydes with acetophenones, to produce chalcones, is the final loss of hydroxide and formation of the C═C bond. This conclusion is based on a study of the partitioning ratios of the intermediate ketols and on the solvent kinetic isotope effects, whereby the condensations are faster in D2O than in H2O, regardless of substitution. PMID:27281298

  20. The Dynamics of Aerosols in Condensational Scrubbers

    DEFF Research Database (Denmark)

    Johannessen, Jens Tue; Christensen, Jan A.; Simonsen, Ole;

    1997-01-01

    A mathematical model for the simulation of the dynamics of aerosol change in condensational scrubbers and scrubbing condensers is proposed. The model is applicable for packed column gas/liquid contact when plug flow can be assumed. The model is compared with experimental data for particle removal...... in a pilot plant condensational scrubber. The model can satisfactorily predict particle growth and particle deposition by diffusional, convective and inertial mechanisms for a wide range of conditions. The parameters of principal importance for the model precision are identified and a procedure...