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1	Genetic variation in <i>Pro-melanin-concentrating</i> hormone affects carcass traits in <i>Bos taurus</i> cattle Helgeson, Sarah Caroline 26 October 2007 The purpose of this research was to determine whether genetic variation existed within <i>Bos taurus</i> Pro-melanin-concentrating hormone (PMCH), and whether this variation would affect carcass traits. PMCH had previously been shown to affect appetite and metabolism in rodent species, thus it was desirable to determine whether the gene had a similar effect in cattle, which could be interpreted based on carcass measurements of weight gain and fat production. Cattle PMCH was sequenced and an adenosine-to-thymine (A>T) single nucleotide polymorphism (SNP) was detected 134 bp upstream of the translational start site. The SNP alleles were determined to significantly affect carcass traits including average fat and grade fat in two populations of cattle, and shear force measurements in one population. The adenosine homozygotes were found to have the highest fat levels and the thymine homozygotes the least, while the heterozygous animals had intermediate fat levels. Shear force values in the one available population indicated that cuts of meat from the adenosine homozygotes were most tender, while cuts from the thymine homozygotes were least tender. <p>The SNP was also found to significantly affect tenderness and palatability of meat, as evaluated by a consumer taste panel. The meat from adenosine homozygotes was found to be most tender and palatable. These results could not be validated as this data was unavailable in additional populations. <p>The location of the SNP suggested that it may affect PMCH transcription rates. In silico examination of the different alleles indicated that the thymine allele introduces a novel transcriptional repressor binding site for Adenovirus E4 Promoter Binding protein (E4BP4). Thus, it is believed that the SNP may affect transcriptional levels of the gene by reducing transcription rates in the presence of the thymine allele. <p>Cattle producers are expected to produce cattle with consistent amounts of lean meat and fat. Genetic testing of alleles found to affect fat production and meat tenderness traits are currently available to producers. A DNA test to select breeding stock based on PMCH alleles could be used in conjunction with other tests currently available to further improve carcass quality by selecting for animals with beneficial alleles at numerous genetic loci. Additionally, producers could make use of these findings to genetically sort cattle upon feedlot entry, maximizing the consistency of the finished beef product. PMCH MCH NEI NGE BTA5
2	Genetic variation in <i>Pro-melanin-concentrating</i> hormone affects carcass traits in <i>Bos taurus</i> cattle Helgeson, Sarah Caroline 26 October 2007 (has links) The purpose of this research was to determine whether genetic variation existed within <i>Bos taurus</i> Pro-melanin-concentrating hormone (PMCH), and whether this variation would affect carcass traits. PMCH had previously been shown to affect appetite and metabolism in rodent species, thus it was desirable to determine whether the gene had a similar effect in cattle, which could be interpreted based on carcass measurements of weight gain and fat production. Cattle PMCH was sequenced and an adenosine-to-thymine (A>T) single nucleotide polymorphism (SNP) was detected 134 bp upstream of the translational start site. The SNP alleles were determined to significantly affect carcass traits including average fat and grade fat in two populations of cattle, and shear force measurements in one population. The adenosine homozygotes were found to have the highest fat levels and the thymine homozygotes the least, while the heterozygous animals had intermediate fat levels. Shear force values in the one available population indicated that cuts of meat from the adenosine homozygotes were most tender, while cuts from the thymine homozygotes were least tender. <p>The SNP was also found to significantly affect tenderness and palatability of meat, as evaluated by a consumer taste panel. The meat from adenosine homozygotes was found to be most tender and palatable. These results could not be validated as this data was unavailable in additional populations. <p>The location of the SNP suggested that it may affect PMCH transcription rates. In silico examination of the different alleles indicated that the thymine allele introduces a novel transcriptional repressor binding site for Adenovirus E4 Promoter Binding protein (E4BP4). Thus, it is believed that the SNP may affect transcriptional levels of the gene by reducing transcription rates in the presence of the thymine allele. <p>Cattle producers are expected to produce cattle with consistent amounts of lean meat and fat. Genetic testing of alleles found to affect fat production and meat tenderness traits are currently available to producers. A DNA test to select breeding stock based on PMCH alleles could be used in conjunction with other tests currently available to further improve carcass quality by selecting for animals with beneficial alleles at numerous genetic loci. Additionally, producers could make use of these findings to genetically sort cattle upon feedlot entry, maximizing the consistency of the finished beef product. PMCH MCH NEI NGE BTA5
3	Analysis of PMCH and LEP genotypes and study of the ITM2A gene as a basis for selection of beef replacement heifers 2015 December 1900 (has links) The need for a more reliable method to select beef heifers to retain as replacement dams has become a concern in the beef industry. Two polymorphisms described in leptin (LEP), p.Arg25Cys, and pro-melanin concentrating hormone (PMCH), g.-134A>T, have already been shown to improve carcass quality in beef cattle. This study was designed to evaluate any additional advantages of these polymorphisms in terms of heifer conception and calving success and lactational milk yield measured indirectly by their calves’ early ADG while they were primarily on lactation. A dominant effect of the dam’s PMCH T allele was observed on improved calf early ADGs in Simmental heifer dams, although not in Angus heifer dams. This effect could be useful in cow-calf operations where calves were suckling their dams for a longer period before sending the cow-calf pairs out to summer pasture. The dam LEP genotype did not show an effect on their calves’ ADG. This was assumed to be due to low body fat reserves of the heifer dams at the age of two years, allowing for only low levels of leptin. Even though heifer conception was not affected by their LEP and PMCH genotypes, it would be worth evaluating their rebreeding success in the presence of these SNPs in the future. The Integral Membrane Protein 2A (ITM2A) was hypothesized as a candidate gene for frame size in cattle. DNA fragments from 20 cattle, matching the predicted exons of the cattle ITM2A gene, were sequenced to determine whether genetic variation existed. However, the sequence obtained based on the predicted cattle ITM2A sequences appeared to be a pseudogene, rather than the actual cattle ITM2A gene, because exons 1, 2, 3 and 5 contained stop codons. Since frame size has been reported to be associated with the reproductive performance of beef dams and their calves’ growth characteristics, it would be useful to characterize this gene once an improved cattle genome assembly is available. LEP PMCH ITM2A Angus Simmental ADG lactation frame size pseudogene
4	Development and Evaluation of a Permeation Plug Release Vessel (PPRV) for the Release of Perfluoromethylcyclohexane (PMCH) in Underground Mine Tracer Gas Studies Jong, Edmund Chime 20 January 2014 (has links) The use of sulfur hexafluoride (SF6) as a tracer gas for analyzing underground mine ventilation systems has been practiced for over 30 years. As a result, the methods used to release, sample, and analyze SF6 are well accepted. Although improvements are still being made to enhance the analysis of this tracer, the overall technique remains largely the same. However, as the complexity and size of underground mine ventilation networks increase, coupled with steadily rising SF6 background levels, the ability of a single gas to function as a convenient, rapid means of analysis diminishes. The utilization of multiple tracer gases can mitigate these problems by allowing for a more comprehensive evaluation using multi-zone techniques. A well-documented alternative in HVAC studies to SF6 as a tracer are perfluorocarbon tracers (PFT). Many PFTs exist as volatile liquids at room temperature and pressure. This characteristic prevents a PFT from being released using the same technique as SF6. This paper introduces a passive release method for PMCH. Details about the development of the permeation plug release vessel (PPRV) from creating a GC calibration curve for vapor PMCH to the final field evaluation are presented. The following study successfully developed a mine-scale PPRV. The PPRV is designed to passively deploy PMCH vapor at linear. An equation was derived in this study that allows the prediction of the release rate as a function of temperature and plug thickness. Details regarding the development of the PPRV from preliminary laboratory studies to final field evaluations are provided. / Ph. D. tracer gas PMCH PFT passive release mine ventilation underground mines gas chromatography
5	4G LTE : eMBMS with MBSFN Service Simulation using OPNET Walid, Abdelrahman January 2014 (has links) Long Term Evolution (LTE) known in the market as 4G LTE, it is an evolution of the GSM/UMTS standard. The overall aim of LTE was to provide a new radio access technology focusing on packet-switched data only. LTE has provided a new peak download rates, low data transfer latencies, and improved the support for mobility. 3Th Generation Partnership Project (3GPP) specialized that LTE released 10 and beyond known as LTE-advanced it is the second evolution of LTE. It has some services such as Coordinated Multipoint Transmission and Reception (CoMP), evolved Multimedia Broadcast and Multicast Service (eMBMS) with Multicast-Broadcast Single-Frequency Network (MBSFN). The development still continuous on LTE-advanced, it is intended to meet the requirement of advanced application that will become common in the wireless marketplace in future. The goals of this project is to simulate one of LTE-A services on LTE standard such as CoMP or/and eMBMS with MBSFN using OPENT LTE, and measure some statistic such as spectral efficiency and also some other statistics, describe centralization vs. decentralization in LTE, and synchronization in the base station in LTE. OPNET LTE support eMBMS with MBSFN, and don’t support CoMP, the simulation has been done by using eMBMS with MBSFN. Finally the objectives of the project has achieved, the result show that when eMBMS with MBSFN is implemented the throughput increased in the downlink to about 5.52 Mbps and in the uplink to about 5.18 Mbps, and also the system spectral efficiency increased in eNB1 from about 10.25 (bits/s/Hz/cell) to about 13.75 (bits/s/Hz/cell) and in eNB2 from about 10.25 (bits/s/Hz/cell) to about 17.25 (bits/s/Hz/cell). The project also answers if it is possible to have centralization in LTE, describe synchronization in the base station in LTE, and if OPNET is useful for big research. 3G 3GPP 4G CoMP CSI CSI-IM CSI-RS eMBMS eNB EPC EPS E-UTRAN GSM HSPA IGMP IGRP ITU-T LTE LTE-A MAC MBSC MBSFN MCE MCS MFN MME OFDM OFDMA OPNET OSPF PDN-GW PDSCH PMCH PUCCH PUSCH QoS SAE SC-FDMA S-GW TDD TD-SCMDA UE UTMS WCDMA. Computer Engineering Datorteknik

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