251 research outputs found

    A Test pf Calf Rations -- Methods of Controlling Contamination of Milk during Milking

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    A Test of Calf Rations Since the spring of 1899 the Department of Dairy Husbandry has been conducting experiments in calf rearing by using hand separator skim-milk and light rations of grain. The first test was published in Bulletin No. 68 of this Station and dealt with a comparison of calves reared by hand with those sucking their dams. The hand-fed calves were reared on skim-milk, ground flaxseed being used to replace the lacking butter fat. This test resulted in a fine lot of calves reared at a very low cost, but it also brought out the fact that much more data were needed in the way of comparing rations to be used with skim-milk. Methods of Controlling Contamination of Milk During Milking Milk contamination takes place largely during the process of milking, especially when the cows are kept in the barn. It was, therefore, thought best to start\u27 with investigations along this first and most troublesome source of infection, namely, milking. The plan of the experiment was to test a number of advocated methods of lessening milk contamination. \u27To do this, four cows were selected from the University dairy herd, all uniform in breed, weight, and time of lactation, so as to avoid, as much as possible,variation among individual animals

    A Test pf Calf Rations -- Methods of Controlling Contamination of Milk during Milking

    Get PDF
    A Test of Calf Rations Since the spring of 1899 the Department of Dairy Husbandry has been conducting experiments in calf rearing by using hand separator skim-milk and light rations of grain. The first test was published in Bulletin No. 68 of this Station and dealt with a comparison of calves reared by hand with those sucking their dams. The hand-fed calves were reared on skim-milk, ground flaxseed being used to replace the lacking butter fat. This test resulted in a fine lot of calves reared at a very low cost, but it also brought out the fact that much more data were needed in the way of comparing rations to be used with skim-milk. Methods of Controlling Contamination of Milk During Milking Milk contamination takes place largely during the process of milking, especially when the cows are kept in the barn. It was, therefore, thought best to start\u27 with investigations along this first and most troublesome source of infection, namely, milking. The plan of the experiment was to test a number of advocated methods of lessening milk contamination. \u27To do this, four cows were selected from the University dairy herd, all uniform in breed, weight, and time of lactation, so as to avoid, as much as possible,variation among individual animals

    Motilitätsstörungen des Ösophagus

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    Zusammenfassung: Motilitätsstörungen des Ösophagus umfassen ein heterogenes Spektrum von Erkrankungen. Primäre Fehlbildungen des Ösophagus sind heute zwar einer verbesserten chirurgischen und gastroenterologischen Therapie zugänglich, führen jedoch zu langfristig persistierender ösophagealer Dysmotilität. Die Achalasie resultiert aus einer gestörten Relaxation des gastroösophagealen Sphinkters. Systemische Erkrankungen können mit einer sekundären ösophagealen Motilitätsstörung einhergehen. Zahlreiche neuromuskuläre Erkrankungen mit viszeraler Manifestation zeigen eine ösophageale Beteiligung. Selten kann eine Aganglionose bis in den Ösophagus reichen. Die wachsende Gruppe der Myopathien schließt metabolische und mitochondriale Störungen ein, deren zunehmende Charakterisierung genetischer Defekte vereinzelt bereits therapeutische Ansätze eröffnet. Infektbedingte Ösophagitiden zeigen besonders bei immunkompromittierten Patienten eine schwere Störung der Motilität. Immunologisch vermittelte Entzündungsprozesse im und um den Ösophagus werden allmählich besser verstanden. Schließlich können seltene Tumoren und tumorartige Läsionen eine Dysmotilität des Ösophagus verursache

    Quantum Cryptography

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    Quantum cryptography could well be the first application of quantum mechanics at the individual quanta level. The very fast progress in both theory and experiments over the recent years are reviewed, with emphasis on open questions and technological issues.Comment: 55 pages, 32 figures; to appear in Reviews of Modern Physic

    The association of homeobox gene expression with stem cell formation and morphogenesis in cultured Medicago truncatula

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    Somatic embryogenesis (SE) is induced in vitro in Medicago truncatula 2HA by auxin and cytokinin but rarely in wild type Jemalong. The putative WUSCHEL (MtWUS), CLAVATA3 (MtCLV3) and the WUSCHEL-related homeobox gene WOX5 (MtWOX5) were investigated in M. truncatula (Mt) and identified by the similarity to Arabidopsis WUS, CLV3 and WOX5 in amino acid sequence, phylogeny and in planta and in vitro expression patterns. MtWUS was induced throughout embryogenic cultures by cytokinin after 24–48 h and maximum expression occurred after 1 week, which coincides with the induction of totipotent stem cells. During this period there was no MtCLV3 expression to suppress MtWUS. MtWUS expression, as illustrated by promoter-GUS studies, subsequently localised to the embryo, and there was then the onset of MtCLV3 expression. This suggests that the expression of the putative MtCLV3 coincides with the WUS-CLAVATA feedback loop becoming operational. RNAi studies showed that MtWUS expression is essential for callus and somatic embryo production. Based on the presence of MtWUS promoter binding sites, MtWUS may be required for the induction of MtSERF1, postulated to have a key role in the signalling required for SE induced in 2HA. MtWOX5 expressed in auxin-induced root primordia and root meristems and appears to be involved in pluripotent stem cell induction. The evidence is discussed that the homeobox genes MtWUS and MtWOX5 are “hijacked” for stem cell induction, which is key to somatic embryo and de novo root induction. In relation to SE, a role for WUS in the signalling involved in induction is discussed

    Transcription Profile Analysis Reveals That Zygotic Division Results in Uneven Distribution of Specific Transcripts in Apical/Basal Cells of Tobacco

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    BACKGROUND: Asymmetric zygotic division in higher plants results in the formation of an apical cell and a basal cell. These two embryonic cells possess distinct morphologies and cell developmental fates. It has been proposed that unevenly distributed cell fate determinants and/or distinct cell transcript profiles may be the underlying reason for their distinct fates. However, neither of these hypotheses has convincing support due to technical limitations. METHODOLOGY/PRINCIPAL FINDINGS: Using laser-controlled microdissection, we isolated apical and basal cells and constructed cell type-specific cDNA libraries. Transcript profile analysis revealed difference in transcript composition. PCR and qPCR analysis confirmed that transcripts of selected embryogenesis-related genes were cell-type preferentially distributed. Some of the transcripts that existed in zygotes were found distinctly existed in apical or basal cells. The cell type specific de novo transcription was also found after zygotic cell division. CONCLUSIONS/SIGNIFICANCE: Thus, we found that the transcript diversity occurs between apical and basal cells. Asymmetric zygotic division results in the uneven distribution of some embryogenesis related transcripts in the two-celled proembryos, suggesting that a differential distribution of some specific transcripts in the apical or basal cells may involve in guiding the two cell types to different developmental destinies

    A Cis-Regulatory Map of the Drosophila Genome

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    Systematic annotation of gene regulatory elements is a major challenge in genome science. Direct mapping of chromatin modification marks and transcriptional factor binding sites genome-wide1, 2 has successfully identified specific subtypes of regulatory elements3. In Drosophila several pioneering studies have provided genome-wide identification of Polycomb response elements4, chromatin states5, transcription factor binding sites6, 7, 8, 9, RNA polymerase II regulation8 and insulator elements10; however, comprehensive annotation of the regulatory genome remains a significant challenge. Here we describe results from the modENCODE cis-regulatory annotation project. We produced a map of the Drosophila melanogaster regulatory genome on the basis of more than 300 chromatin immunoprecipitation data sets for eight chromatin features, five histone deacetylases and thirty-eight site-specific transcription factors at different stages of development. Using these data we inferred more than 20,000 candidate regulatory elements and validated a subset of predictions for promoters, enhancers and insulators in vivo. We identified also nearly 2,000 genomic regions of dense transcription factor binding associated with chromatin activity and accessibility. We discovered hundreds of new transcription factor co-binding relationships and defined a transcription factor network with over 800 potential regulatory relationships
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