Background: According to current guidelines, confirmation that vasectomy results in sterility depends on microscopic examination of postvasectomy semen for the presence of spermatozoa. Guidelines established in 2012 require examination of a fresh specimen within 2 h of collection, which necessitates the patient making an appointment with either the surgeon's office or a licensed clinical laboratory. Twenty-five to 42% of patients fail to comply with postvasectomy semen analysis (PVSA).
View Article and Find Full Text PDFBackground: Achieving food security remains a key challenge for public policy throughout the world. As such, understanding the determinants of food insecurity and the causal relationships between them is an important scientific question. We aim to construct a Bayesian belief network model of food security in rural South Africa to act as a tool for decision support in the design of interventions.
View Article and Find Full Text PDFThe challenge of nowcasting the effect of natural hazard events (e.g., earthquakes, floods, hurricanes) on assets, people and society is of primary importance for assessing the ability of such systems to recover from extreme events.
View Article and Find Full Text PDFBackground: Central to the study of populations, and therefore to the analysis of the development of countries undergoing major transitions, is the calculation of fertility patterns and their dependence on different variables such as age, education, and socio-economic status. Most epidemiological research on these matters rely on the often unjustified assumption of (generalised) linearity, or alternatively makes a parametric assumption (e.g.
View Article and Find Full Text PDFRecent research has provided evidence that mood can spread over social networks via social contagion, but that, in seeming contradiction to this, depression does not. Here, we investigate whether there is evidence for the individual components of mood (such as appetite, tiredness and sleep) spreading through US adolescent friendship networks while adjusting for confounding by modelling the transition probabilities of changing mood state over time. We find that having more friends with worse mood is associated with a higher probability of an adolescent worsening in mood and a lower probability of improving, and vice versa for friends with better mood, for the overwhelming majority of mood components.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
August 2015
We derive analogs of the Jarzynski equality and Crooks relation to characterize the nonequilibrium work associated with changes in the spring constant of an overdamped oscillator in a quadratically varying spatial temperature profile. The stationary state of such an oscillator is described by Tsallis statistics, and the work relations for certain processes may be expressed in terms of q-exponentials. We suggest that these identities might be a feature of nonequilibrium processes in circumstances where Tsallis distributions are found.
View Article and Find Full Text PDFObjective: To assess the accuracy of serology to predict the presence of cytomegalovirus (CMV) in semen of homosexual men without and with HIV coinfection.
Design: Semen CMV was detected by electron microscopy and by polymerase chain reaction (PCR) amplification; paired serum was tested for CMV IgG/IgM. Semen HIV was detected by reverse transcription-PCR.
It is widely accepted that percutaneous nephrostolithotorny (PCNL) is the standard of choice for the removal of large staghorn renal calculi. Although data exists supporting a stagad ureteroscopic as an alternate treatment for stones up to 3 cm in select patients, little data exists to support a ureteroscopic approach for stones as large as 5 cm. We present a case of a 68 year old female with a 5 cm staghorn renal calculus managed successfully with a staged ureteroscopic approach.
View Article and Find Full Text PDFObjective: To detect and identify bacteria in semen by sequencing polymerase chain reaction (PCR)-amplified ribosomal RNA gene regions (rDNAs).
Design: Bacterial rDNAs were detected by PCR amplification of semen DNA. Conditions were adjusted to detect only abundant organisms, no fewer than 20,000 bacteria/mL of semen.
Objectives: To investigate whether interstitial laser coagulation (ILC) is as effective and as safe as transurethral resection of the prostate (TURP). The treatment of choice for bladder outflow obstruction secondary to benign prostatic hyperplasia is TURP. However, ILC is a less invasive outpatient procedure that may be as effective and safe as TURP.
View Article and Find Full Text PDFAIDS Res Hum Retroviruses
July 2002
Immunosuppressive properties of seminal plasma inhibit the recovery of infectious HIV from semen, and led to the view early in the pandemic that semen HIV was transmitted principally by infected semen cells. More recent studies have revealed significant titers of HIV RNA in seminal plasma, however, even from men receiving successful antiviral therapy. Thus, studies of infectious HIV in seminal plasma are important to understanding sexual transmission and response to therapy.
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