891 research outputs found
Greater Yellowstone Coalition v. Flowers: Clearing the Irreparable Harm Hurdle in the Tenth Circuit to Protect Yellowstone Bald Eagles
Comparative genome analysis of Wolbachia strain wAu
BACKGROUND:
Wolbachia intracellular bacteria can manipulate the reproduction of their arthropod hosts, including inducing sterility between populations known as cytoplasmic incompatibility (CI). Certain strains have been identified that are unable to induce or rescue CI, including wAu from Drosophila. Genome sequencing and comparison with CI-inducing related strain wMel was undertaken in order to better understand the molecular basis of the phenotype.
RESULTS:
Although the genomes were broadly similar, several rearrangements were identified, particularly in the prophage regions. Many orthologous genes contained single nucleotide polymorphisms (SNPs) between the two strains, but a subset containing major differences that would likely cause inactivation in wAu were identified, including the absence of the wMel ortholog of a gene recently identified as a CI candidate in a proteomic study. The comparative analyses also focused on a family of transcriptional regulator genes implicated in CI in previous work, and revealed numerous differences between the strains, including those that would have major effects on predicted function.
CONCLUSIONS:
The study provides support for existing candidates and novel genes that may be involved in CI, and provides a basis for further functional studies to examine the molecular basis of the phenotype
Evaluating the desorption of oygen from wine
Thesis (MScAgric)--Stellenbosch University, 2022.ENGLISH ABSTRACT: The removal of dissolved oxygen through desorption is commonly done in winemaking.
Winemakers have indicated that under the same conditions, this process takes place at different
rates, for different wines. The mass transfer of oxygen in six wines and various model wine
solutions, was examined by evaluating the oxygen desorption volumetric mass transfer coefficient
( ), the Sauter mean bubble diameter (D32), gas holdup (), the interfacial area (), and the
oxygen mass transfer coefficient (). One of the wines used was split into two batches, with one
half treated with bentonite, and the other not. A bubble column with a stone sparger was used for
the experiments. The gassing out procedure and a 2nd order model was used to determine .
Bubble imaging was done to determine the interfacial area, and subsequently the .
During oxygen desorption within wine, the values varied between 0.0125 s-1 and 0.0275 s-1
depending on the wine. The value during oxygen desorption within a 10 % ethanol solution
was found to be 0.0275 s1. The addition of a small amount glycerol to this system reduced the
to 0.0225 s-1. Further additions of organic acids did not affect the , while the addition of
protein in the form of BSA and yeast extract reduced the to approximately 0.0175 s-1. The
for during oxygen desorption within a wine that was protein unstable improved from 0.009 s1 to
0.015 s1 after being treated with bentonite.
During desorption, there were no significant variations in the D32 and the interfacial area between
systems containing wines or model wine solutions. Consequently, the variations between the
values could all be ascribed to differences in the . During oxygen desorption, the values
were found to be between 0.015 and 0.045 mm/s within the different wines. The values were
found to be between 0.03 and 0.04 mm/s within a 10% ethanol solution, and within the model
wine solutions containing glycerol and organic acids. The values dropped between 0.02 and
0.03 mm/s with the addition of protein to the model wine solution. Treating a protein unstable wine
with bentonite increased the value from 0.017 mm/s to 0.0225 mm/s.
The combination of the reduction in the when protein was added to a model wine solution, and
the improvement of the when wine was treated with bentonite, suggested that proteins in wine
significantly affect oxygen desorption rates. It is suggested that winemakers can improve the
oxygen within their system by operating at higher gas flowrates to increase the turbulence
during desorption. However, the most effective way of improving the desorption rate is by using
a sparger that produces smaller bubbles, so as to increase the interfacial area. It is suggested
that desorption is performed after fining, as the will be greater.AFRIKAANSE OPSOMMING: Die verwydering van opgeloste suurstof deur middel van desorpsie kom algemeen in
wynbereiding voor. Wynmakers het aangedui dat, onder dieselfde toestande, hierdie proses teen
verskillende tempo’s vir verskillende wyne plaasvind. Die massa-oordrag van suurstof in ses wyne
en verskillende model-wynoplossings is ondersoek deur die volumetriese massa-
oordragkoëffisiënt ( ) van suurstof desorpsie, die Sauter gemiddelde borreldeursnee (D32),
gasvertraging (gas holdup) (), die oppervlakte van die koppelvlak () en die suurstof massa-
oordragkoëffisiënt () te evalueer. Een van die wyne wat gebruik is, is in twee verdeel, die een
helfte waarvan met bentoniet behandel is en die ander nie. ’n Borrelkolom met ’n klip
sprinkeltoestel (stone sparger) is vir die eksperimente gebruik. Die ontgassingsprosedure
(gassing out) en ’n tweede-orde model is gebruik om te bepaal. Borrel beelding (imaging) is
gedoen om die oppervlakte van die koppelvlak, en gevolglik die , te bepaal.
Tydens suurstofdesorpsie in die wyn het die -waardes tussen 0.0125 s-1 en 0.0275 s-1
gewissel, afhangend van die wyn. Die -waarde tydens suurstofdesorpsie met ’n 10%
etanoloplossing was 0.0275 s1. Die toevoeging van ’n klein hoeveelheid gliserol aan hierdie
stelsel het die tot 0.0225 s-1 verminder. Verdere toevoegings van organiese sure het nie die
geaffekteer nie, terwyl die toevoeging van proteïen in die vorm van BSA en gis-ekstrak die
tot ongeveer 0.0175 s-1 verminder het. Die tydens suurstofdesorpsie in ’n wyn wat
proteïen-onstabiel was, het verbeter van 0.009 s1 tot 0.015 s1 ná behandeling met bentoniet.
Tydens desorpsie was daar geen betekenisvolle verandering in die D32 en in die oppervlakte van
die koppelvlak tussen stelsels wat wyn of model-wynoplossings bevat het nie. Gevolglik kon die
verskille in die -waardes almal aan verskille in die toegeskryf word. Tydens
suurstofdesorpsie was die -waardes in die verskillende wyne tussen 0.015 en 0.045 mm/s. Die
-waardes was tussen 0.03 en 0.04 mm/s in ’n 10% etanoloplossing, asook in die model-
wynoplossings wat gliserol en organiese sure bevat het. Die -waardes het met tussen 0.02 en
0.03 mm/s gedaal met die toevoeging van proteïen aan die model-wynoplossing. Die behandeling
van ’n wyn wat proteïen-onstabiel was met bentoniet het die -waarde van 0.017 mm/s tot 0.0225
mm/s verhoog.
Die kombinasie van die afname van die toe proteïen by ’n model-wynoplossing gevoeg is en
die verbetering van die toe die wyn met bentoniet behandel is, suggereer dat proteïene in wyn
die suurstofdesorpsie-tempo’s aansienlik beïnvloed. Daar word voorgestel dat wynmakers die
suurstof- in hulle stelsel kan verbeter deur teen hoër gasvloeitempo’s te werk om die turbulensie
tydens desorpsie te verhoog. Die doeltreffendste manier om die desorpsietempo te verbeter, is
egter om ’n sprinkeltoestel te gebruik wat kleiner borrels produseer om sodoende die oppervlakte
van die koppelvlak te vergroot. Daar word ook voorgestel dat desorpsie ná brei uitgevoer word,
aangesien die groter sal wees
Depolarization of sperm membrane potential is a common feature of men with subfertility and is associated with low fertilization rate at IVF
STUDY QUESTION. Are significant abnormalities in outward (K+) conductance and resting membrane potential (Vm) present in the spermatozoa of patients undertaking IVF and ICSI and if so, what is their functional effect on fertilization success? SUMMARY ANSWER. Negligible outward conductance (≈5% of patients) or an enhanced inward conductance (≈4% of patients), both of which caused depolarization of Vm, were associated with a low rate of fertilization following IVF. WHAT IS KNOWN ALREADY. Sperm-specific potassium channel knockout mice are infertile with defects in sperm function, suggesting that these channels are essential for fertility. These observations suggest that malfunction of K+ channels in human spermatozoa might contribute significantly to the occurrence of subfertility in men. However, remarkably little is known of the nature of K+ channels in human spermatozoa or the incidence and functional consequences of K+ channel defects. STUDY DESIGN, SIZE AND DURATION. Spermatozoa were obtained from healthy volunteer research donors and subfertile IVF and ICSI patients attending a hospital assisted reproductive techniques clinic between May 2013 and December 2015. In total, 40 IVF patients, 41 ICSI patients and 26 normozoospermic donors took part in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS. Samples were examined using electrophysiology (whole-cell patch clamping). Where abnormal electrophysiological characteristics were identified, spermatozoa were further examined for Ca2+ influx induced by progesterone and penetration into viscous media if sufficient sample was available. Full exome sequencing was performed to specifically evaluate potassium calcium-activated channel subfamily M α 1 (KCNMA1), potassium calcium-activated channel subfamily U member 1 (KCNU1) and leucine-rich repeat containing 52 (LRRC52) genes and others associated with K+ signalling. In IVF patients, comparison with fertilization rates was done to assess the functional significance of the electrophysiological abnormalities. MAIN RESULTS AND THE ROLE OF CHANCE. Patch clamp electrophysiology was used to assess outward (K+) conductance and resting membrane potential (Vm) and signalling/motility assays were used to assess functional characteristics of sperm from IVF and ICSI patient samples. The mean Vm and outward membrane conductance in sperm from IVF and ICSI patients were not significantly different from those of control (donor) sperm prepared under the same conditions, but variation between individuals was significantly greater (P< 0.02) with a large number of outliers (>25%). In particular, in ≈10% of patients (7/81), we observed either a negligible outward conductance (4 patients) or an enhanced inward current (3 patients), both of which caused depolarization of Vm. Analysis of clinical data from the IVF patients showed significant association of depolarized Vm (≥0 mV) with low fertilization rate (P= 0.012). Spermatozoa with electrophysiological abnormities (conductance and Vm) responded normally to progesterone with elevation of [Ca2+]i and penetration of viscous medium, indicating retention of cation channel of sperm (CatSper) channel function. LIMITATIONS, REASONS FOR CAUTION. For practical, technical, ethical and logistical reasons, we could not obtain sufficient additional semen samples from men with conductance abnormalities to establish the cause of the conductance defects. Full exome sequencing was only available in two men with conductance defects. WIDER IMPLICATIONS OF THE FINDINGS. These data add significantly to the understanding of the role of ion channels in human sperm function and its impact on male fertility. Impaired potassium channel conductance (Gm) and/or Vm regulation is both common and complex in human spermatozoa and importantly is associated with impaired fertilization capacity when the Vm of cells is completely depolarized
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Transcriptional down-regulation of ccr5 in a subset of HIV+ controllers and their family members.
HIV +Elite and Viremic controllers (EC/VCs) are able to control virus infection, perhaps because of host genetic determinants. We identified 16% (21 of 131) EC/VCs with CD4 +T cells with resistance specific to R5-tropic HIV, reversed after introduction of ccr5. R5 resistance was not observed in macrophages and depended upon the method of T cell activation. CD4 +T cells of these EC/VCs had lower ccr2 and ccr5 RNA levels, reduced CCR2 and CCR5 cell-surface expression, and decreased levels of secreted chemokines. T cells had no changes in chemokine receptor mRNA half-life but instead had lower levels of active transcription of ccr2 and ccr5, despite having more accessible chromatin by ATAC-seq. Other nearby genes were also down-regulated, over a region of ~500 kb on chromosome 3p21. This same R5 resistance phenotype was observed in family members of an index VC, also associated with ccr2/ccr5 down-regulation, suggesting that the phenotype is heritable
Strategic E-book Acquisition with ebrary & YBP
The presentation describes how YBP, ebrary and IUPUI University Library collaborated to implement IUPUI's strategic ebook acquisition model. Specifically, the presentation describes the results of the first 6 months of the library's patron driven acquisition pilot project
Youth Ambassadors Reaching Out (YARO): Lessons learned from the implementation of a youth-based cancer education program
We know that many factors contribute to the exacerbation of cancer health disparities. These inequities observed in adulthood may have originated from behaviors occurring in early adolescence. We believe that increasing awareness of cancer prevention in youth may help reduce future disparities. Our community partners identified a need for youth-oriented cancer prevention and helped design the pilot Youth Ambassadors Reaching Out (YARO) program. YARO provided cancer prevention and health disparities education and exposure to health careers to 73 middle school students between 2012-2016. YARO included didactic sessions (health disparities, smoking prevention, physical activity, nutrition), a cancer center tour, and Photovoice project. Students were encouraged to serve as ambassadors by sharing lessons learned with others. Participants demonstrated increases in cancer prevention knowledge during the program. Evaluation data revealed that students served as ambassadors by sharing information with others about healthy behaviors, improving their own health habits, and volunteering in their communities
Development and Validation of an Improved PCR Method Using the 23S-5S Intergenic Spacer for Detection of Rickettsiae in Dermacentor variabilis Ticks and Tissue Samples from Humans and Laboratory Animals
A novel nested PCR assay was developed to detect Rickettsia spp. in ticks and tissue samples from humans and laboratory animals. Primers were designed for the nested run to amplify a variable region of the 23S-5S intergenic spacer (IGS) of Rickettsia spp. The newly designed primers were evaluated using genomic DNA from 11 Rickettsia species belonging to the spotted fever, typhus, and ancestral groups and, in parallel, compared to other Rickettsia -specific PCR targets ( ompA , gltA , and the 17-kDa protein gene). The new 23S-5S IGS nested PCR assay amplified all 11 Rickettsia spp., but the assays employing other PCR targets did not. The novel nested assay was sensitive enough to detect one copy of a cloned 23S-5S IGS fragment from “ Candidatus Rickettsia amblyommii.” Subsequently, the detection efficiency of the 23S-5S IGS nested assay was compared to those of the other three assays using genomic DNA extracted from 40 adult Dermacentor variabilis ticks. The nested 23S-5S IGS assay detected Rickettsia DNA in 45% of the ticks, while the amplification rates of the other three assays ranged between 5 and 20%. The novel PCR assay was validated using clinical samples from humans and laboratory animals that were known to be infected with pathogenic species of Rickettsia . The nested 23S-5S IGS PCR assay was coupled with reverse line blot hybridization with species-specific probes for high-throughput detection and simultaneous identification of the species of Rickettsia in the ticks. “ Candidatus Rickettsia amblyommii,” R. montanensis , R. felis , and R. bellii were frequently identified species, along with some potentially novel Rickettsia strains that were closely related to R. bellii and R. conorii
The content and context of physicians' communication with males about human papillomavirus vaccination
A physician's recommendation for human papillomavirus (HPV) vaccine is a key predictor of vaccine uptake; however, little is known about how physicians communicate about HPV vaccine with male patients. We sought to describe physicians' HPV vaccine communication practices with males who are of vaccine-eligible age (9-26 years). We surveyed representative samples of pediatric and family medicine physicians in Florida, and assessed whether physicians present HPV vaccine as optional or routine, and as a vaccine that prevents cancer. We also assessed the type of visit during which physicians discuss HPV vaccine with adolescent males and whether other healthcare providers in the practice discuss HPV vaccine or make the initial recommendation. We received 367 completed surveys (50.7% response rate). Few physicians (29.9%) reported they typically present HPV vaccine as routine to males ages 11-12 years, who constitute the target group for routine vaccination. When discussing HPV vaccination, many physicians reported somewhat or strongly emphasizing cancer prevention (80.0%). Physicians most often discussed HPV vaccine when they saw patients for well-child visits (93.0%) and least often at acute care visits (15.3%). Over half reported that at least one other healthcare professional in their practice discusses (56.1%) or makes the initial recommendation for (54.9%) HPV vaccination. Many physicians in our sample are presenting HPV vaccine as optional rather than routine and are missing opportunities to communicate with males about the vaccine. Our findings identify areas for future interventions to improve physicians' HPV vaccine communication and, ultimately, increase the use of this cancer-preventing vaccine
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