Hydraulic efficiency of a hydrostatic transmission with a variable displacement pump and motor

Title from PDF of title page (University of Missouri--Columbia, viewed on March 7, 2013).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Roger FalesIncludes bibliographical references.M. S. University of Missouri--Columbia 2012.Dissertations, Academic -- University of Missouri--Columbia -- Mechanical and aerospace engineering."December 2012"Pumps and motors are commonly connected hydraulically to create hydrostatic drives, also known as hydrostatic transmissions. A typical hydrostatic transmission consists of a variable displacement pump and a fixed displacement motor. Maximum efficiency is typically created for the system when the motor operates at maximum volumetric displacement. The objective of this research is to determine if a hydrostatic transmission with a variable displacement motor can be more efficient than one with a fixed displacement motor. A work cycle for a Caterpillar 320D excavator was created and the efficiency of the hydrostatic drive system, controlling the swing circuit, with a fixed displacement motor was compared to the efficiency with a variable displacement motor. A PID and an H∞ controller were designed for a position control model, as well as velocity control. It was found that while it may seem obvious to achieve maximum efficiency at maximum displacement, there are some cases where maximum efficiency is achieved at a lower displacement. It was also found that for the given work cycle, a hydrostatic transmission with a variable displacement motor can be more efficient

Ring oscillator based injection locked clock multiplier

This thesis describes a ring-based injection locked clock multiplier (ILCM) designed with the goal of generating a high-frequency and low-jitter clock. Building on prior research done on injection locking, this design uses a reference frequency doubling technique to push the noise bandwidth of the circuit to Fref/3 to suppress DCO noise to a large extent. A background duty cycle error correction technique is employed to correct errors on the doubled clock that could be detrimental to performance. The design also modifies an existing architecture to achieve type-II suppression of DCO noise in order to fully suppress the flicker noise which becomes prevalent in low process nodes. The prototype ILCM was fabricated in TSMC 65 nm CMOS technology. Thorough testing was performed to characterize the effectiveness of the aforementioned techniques. The circuit achieves 340 fsrms integrated jitter when operating at 5 GHz while only consuming 5.3 mW of power. The ILCM's figure of merit, -242.4 dB, is on par with state-of-the-art ring-based clock multipliers while operating at a much higher output frequency and multiplication factor than previously published work. These results indicate the effectiveness of reference frequency doubling in a ring-based, high-performance clock multiplier design

Concert recording 2021-11-07a

[Track 1]. La maniere de Shumann /Jean-Michel Defaye -- [Track 2]. Sang till lotta / Jan Sandstrom -- [Track 3]. Concertino in B♭ / Ernst Sachse -- [Track 4]. Nearer my God to thee for 9 celli / James Stevens -- [Track 5]. Ave Maria / Franz Biebl -- [Track 6]. Soundtrack for trombone / Brian Sadler

Concert recording 2021-10-28

[Track 1]. À la manière de Schumann / Jean-Michel Defaye -- [Track 2]. Bushes and briars / Ralph Vaughan Williams ; arranged by Richard Myers-- [Track 3]. Now is the month of Maying / Thomas Morley-- [Track 4]. Concerto in one movement / Alexey Lebedev -- [Track 5]. Suite of Lieder. I. Lob der Einsamkeit ; II. Grab und Mond ; III. Widersprich / Franz Schubert ; arranged by Rowell -- [Track 6]. The song of King David / Norman Bolter -- [Track 7]. Leviathan / Jack Wilds -- [Track 8]. -- Ave Maria / Anton Bruckner ; arranged by Donald R. Frederick -- [Track 9]. Prelude, op. 34, no. 19. / Dimitri Shostakovich-- [Track 10]. A canzona concoction / Allen Molineux

HIV-1 RNA Levels and Antiretroviral Drug Resistance in Blood and Non-Blood Compartments from HIV-1–Infected Men and Women enrolled in AIDS Clinical Trials Group Study A5077

Background: Detectable HIV-1 in body compartments can lead to transmission and antiretroviral resistance. Although sex differences in viral shedding have been demonstrated, mechanisms and magnitude are unclear. We compared RNA levels in blood, genital-secretions and saliva; and drug resistance in plasma and genital-secretions of men and women starting/changing antiretroviral therapy (ART) in the AIDS Clinical Trials Group (ACTG) 5077 study. Methods: Blood, saliva and genital-secretions (compartment fluids) were collected from HIV-infected adults (≥13 years) at 14 United-States sites, who were initiating or changing ART with plasma viral load (VL) ≥2,000 copies/mL. VL testing was performed on all compartment fluids and HIV resistance genotyping on plasma and genital-secretions. Spearman rank correlations were used to evaluate concordance and Fisher’s and McNemar’s exact tests to compare VL between sexes and among compartments. Results: Samples were available for 143 subjects; 36% treated (23 men, 29 women) and 64% ‘untreated’ (40 men, 51 women). RNA detection was significantly more frequent in plasma (100%) than genital-secretions (57%) and saliva (64%) (P<0.001). A higher proportion of men had genital shedding versus women (78% versus 41%), and RNA detection was more frequent in saliva versus genital-secretions in women when adjusted for censoring at the limit of assay detection. Inter-compartment fluid VL concordance was low in both sexes. In 22 (13 men, 9 women) paired plasma-genital-secretion genotypes from treated subjects, most had detectable resistance in both plasma (77%) and genital-secretions (68%). Resistance discordance was observed between compartments in 14% of subjects. Conclusions: HIV shedding and drug resistance detection prior to initiation/change of ART in ACTG 5077 subjects differed among tissues and between sexes, making the gold standard blood-plasma compartment assessment not fully representative of HIV at other tissue sites. Mechanisms of potential sex-dependent tissue compartmentalization should be further characterized to aid in optimizing treatment and prevention of HIV transmission. Trial Registration ClinicalTrials.gov NCT0000748

The Impact of Implementing a Test, Treat and Retain HIV Prevention Strategy in Atlanta among Black Men Who Have Sex with Men with a History of Incarceration: A Mathematical Model

Background Annually, 10 million adults transition through prisons or jails in the United States (US) and the prevalence of HIV among entrants is three times higher than that for the country as a whole. We assessed the potential impact of increasing HIV Testing/Treatment/Retention (HIV-TTR) in the community and within the criminal justice system (CJS) facilities, coupled with sexual risk behavior change, focusing on black men-who-have-sex-with-men, 15–54 years, in Atlanta, USA. Methods We modeled the effect of a HIV-TTR strategy on the estimated cumulative number of new (acquired) infections and mortality, and on the HIV prevalence at the end of ten years. We additionally assessed the effect of increasing condom use in all settings. Results In the Status Quo scenario, at the end of 10 years, the cumulative number of new infections in the community, jail and prison was, respectively, 9246, 77 and 154 cases; HIV prevalence was 10815, 69 and 152 cases, respectively; and the cumulative number of deaths was 2585, 18 and 34 cases, respectively. By increasing HIV-TTR coverage, the cumulative number of new infections could decrease by 15% in the community, 19% in jail, and 8% in prison; HIV prevalence could decrease by 8%, 9% and 7%, respectively; mortality could decrease by 20%, 39% and 18%, respectively. Based on the model results, we have shown that limited use and access to condoms have contributed to the HIV incidence and prevalence in all settings. Conclusions Aggressive implementation of a CJS-focused HIV-TTR strategy has the potential to interrupt HIV transmission and reduce mortality, with benefit to the community at large. To maximize the impact of these interventions, retention in treatment, including during the period after jail and prison release, and increased condom use was vital for decreasing the burden of the HIV epidemic in all settings

Glycine and Folate Ameliorate Models of Congenital Sideroblastic Anemia

Sideroblastic anemias are acquired or inherited anemias that result in a decreased ability to synthesize hemoglobin in red blood cells and result in the presence of iron deposits in the mitochondria of red blood cell precursors. A common subtype of congenital sideroblastic anemia is due to autosomal recessive mutations in the SLC25A38 gene. The current treatment for SLC25A38 congenital sideroblastic anemia is chronic blood transfusion coupled with iron chelation. The function of SLC25A38 is not known. Here we report that the SLC25A38 protein, and its yeast homolog Hem25, are mitochondrial glycine transporters required for the initiation of heme synthesis. To do so, we took advantage of the fact that mitochondrial glycine has several roles beyond the synthesis of heme, including the synthesis of folate derivatives through the glycine cleavage system. The data were consistent with Hem25 not being the sole mitochondrial glycine importer, and we identify a second SLC25 family member Ymc1, as a potential secondary mitochondrial glycine importer. Based on these findings, we observed that high levels of exogenous glycine, or 5-aminolevulinic acid (5-Ala) a metabolite downstream of Hem25 in heme biosynthetic pathway, were able to restore heme levels to normal in yeast cells lacking Hem25 function. While neither glycine nor 5-Ala could ameliorate SLC25A38 congenital sideroblastic anemia in a zebrafish model, we determined that the addition of folate with glycine was able to restore hemoglobin levels. This difference is likely due to the fact that yeast can synthesize folate, whereas in zebrafish folate is an essential vitamin that must be obtained exogenously. Given the tolerability of glycine and folate in humans, this study points to a potential novel treatment for SLC25A38 congenital sideroblastic anemia.Genome Canada as large-scale applied research project with funding contributions from the Dalhousie Medical Research Foundation, the Nova Scotia Research Innovation Trust, and the Nova Scotia Department of Health and Wellnes

Sudden Infant Death Syndrome (SIDS) and the routine otoacoustic emission infant hearing screening test: an epidemiological retrospective case-control study

Objectives To investigate whether decreased otoacoustic emission (OAE) signal recordings in the right ear are associated with an increased risk of sudden infant death syndrome (SIDS) and to monitor any temporal changes in risk factors. Design Retrospective case-control study. Setting Telephone interviews with families recruited in England between July 2016 and October 2017 who experienced the unexpected death of a child <4 years old since 2008 and control families recruited from maternity wards in Bristol and Birmingham. Participants We recruited 91 (89%) of the 102 bereaved families who made initial contact, 64 deaths were under 1 year (sudden unexpected death in infancy) of which 60 remained unexplained (SIDS). Of the 220 control families, 194 (88%) follow-up interviews were conducted. We had analysable hearing data for 24 SIDS infants (40%) and 98 controls (51%). Results OAE signals were marginally increased rather than decreased among SIDS infants for the right ear, especially at lower frequencies, but not significantly so. The strongest predictors of SIDS were bed-sharing in hazardous (infant sleeping next to a carer who smoked, drank alcohol or slept on a sofa) circumstances (35% vs 3% controls, p<0.0001), infants found prone (33% vs 3% controls, p<0.0001) and infants whose health in the final week was â € not good' (53% vs 9% controls, p<0.0001). The prevalence of maternal smoking during pregnancy among both SIDS mothers (20%) and controls (10%) was much lower than previous studies. Conclusions Hearing data were difficult to obtain; larger numbers would be needed to determine if asymmetrical differences between the right and left ear were a marker for SIDS. A national prospective registry for monitoring and a renewed campaign to a new generation of parents needs to be considered underlining the initial message to place infants on their backs for sleep and the more recent message to avoid bed-sharing in hazardous circumstances

Concert recording 2019-10-23

[Track 1]. Morgenmusik. I. Massig bewegt [Track 2]. II. Langsame viertel [Track 3]. III. Bewegt / Paul Hindemith -- [Track 4]. Joshua fit de Battle of Jericho / traditional, arranged by Chris Woods -- [Track 5]. Fantasy for trombone / Elizabeth Raum -- [Track 6]. Suite. I. Passepied [Track 7]. II. Arietta [Track 8]. III. March / Johann Adolphe Hesse, ed. William Glover -- [Track 9]. Suite for four trombones. I. Poco maestoso [Track 10]. II. Sarabanda [Track 11]. III. Alla marcia [Track 12]. IV. Spirituale [Track 13]. V. Finale alla fuga / Gordon Jacob -- [Track 14]. Concertino. II. Aria: Andante sostenuto [Track 15]. III. Finale: Allegro giocoso / Lars-Erik Larsson -- [Track 16]. Andante et allegro / Joseph Edouard Barat -- [Track 17]. Horizon of the Aten / Anthony Barfield -- [Track 18]. Round midnight / Thelonious Monk, arranged by Slide Hampton

A biophysical model of cell adhesion mediated by immunoadhesin drugs and antibodies

A promising direction in drug development is to exploit the ability of natural killer cells to kill antibody-labeled target cells. Monoclonal antibodies and drugs designed to elicit this effect typically bind cell-surface epitopes that are overexpressed on target cells but also present on other cells. Thus it is important to understand adhesion of cells by antibodies and similar molecules. We present an equilibrium model of such adhesion, incorporating heterogeneity in target cell epitope density and epitope immobility. We compare with experiments on the adhesion of Jurkat T cells to bilayers containing the relevant natural killer cell receptor, with adhesion mediated by the drug alefacept. We show that a model in which all target cell epitopes are mobile and available is inconsistent with the data, suggesting that more complex mechanisms are at work. We hypothesize that the immobile epitope fraction may change with cell adhesion, and we find that such a model is more consistent with the data. We also quantitatively describe the parameter space in which binding occurs. Our results point toward mechanisms relating epitope immobility to cell adhesion and offer insight into the activity of an important class of drugs.Comment: 13 pages, 5 figure