Projective differential invariants of two curves

No abstract availabl

Preliminary data on boulders at station 6, Apollo 17 landing site

A cluster of boulders at Station 6 (Apollo 17 landing site) consists of breccias derived from the North Massif. Three preliminary lithologic units were established, on the basis of photogeologic interpretations; all lithologies identified photogeologically were sampled. Breccia clasts and matrices studied petrographically and chemically fall into two groups by modal mineralogy: (1) low-K Fra Mauro or high basalt composition, consisting of 50-60% modal feldspar, approximately 45% orthopyroxene and 1-7% Fe-Ti oxide; (2) clasts consisting of highland basalt composition, consisting of 70% feldspar, 30% orthopyroxene and olivine and a trace of Fe-Ti oxide

Preventing Perinatal Transmission of HIV Costs and Effectiveness of a Recommended Intervention

In the United States, nearly all new human immunodeficiency virus (HIV) infections in children are acquired through perinatal (mother-to-infant) transmission. Each year, approximately 7000 infants are born to HIV-infected women in the United States.1 Without intervention, an estimated 15-30% of these infants would become infected.2 In 1994, results of the AIDS Clinical Trial Group (ACTG) Protocol 076 showed that treatment of infected pregnant women and their infants with zidovudine (ZDV) reduced the rate of perinatal HIV transmission from 25% to 8%.3,4 Following these findings, the Public Health Service (PHS) issued recommendations for ZDV therapy to prevent perinatal HIV transmission5 and for HIV counseling and voluntary testing of pregnant women.

The initial impact of the COVID-19 pandemic on the diagnosis of new cancers at a large pathology laboratory in the public health sector, Western Cape Province, South Africa

Background. The COVID-19 pandemic has disrupted cancer diagnostic services. A decline in the number of new cancers being diagnosed over a relatively short term implies a delay in diagnosis and subsequent treatment. This delay is expected to have a negative effect on cancerrelated morbidity and mortality. The impact of the pandemic on the number of new cancer diagnoses in our setting is unknown.Objectives. To assess the impact of COVID-19 on the number of new cancers diagnosed at our institution in the first 3 months following the implementation of lockdown restrictions, by focusing on common non-cutaneous cancers.Methods. A retrospective laboratory-based audit was performed at a large anatomical pathology laboratory in Western Cape Province, South Africa. The numbers of new diagnoses for six common cancers (breast, prostate, cervix, large bowel, oesophagus and stomach) from 1 April 2020 to 30 June 2020 were compared with the corresponding period in 2019.Results. Histopathological diagnoses for the six cancers combined decreased by 193 (–36.3%), from 532 new cases in the 2019 study period to 339 in the corresponding period in 2020. Substantial declines were seen for prostate (–58.2%), oesophageal (–44.1%), breast (–32.9%), gastric (–32.6%) and colorectal cancer (–29.2%). The smallest decline was seen in cervical cancer (–7%). New breast cancers diagnosed by cytopathology declined by 61.1%.Conclusions. The first wave of the COVID-19 pandemic and the associated response resulted in a substantial decline in the number of new cancer diagnoses, implying a delay in diagnosis. Cancer-related morbidity and mortality is expected to rise as a result, with the greatest increase in mortality expected from breast and colorectal cancer

Introducing a core curriculum for respiratory sleep practitioners

The background and purpose of the HERMES (Harmonising Education in Respiratory Medicine for European Specialists) initiative has been discussed at length in previous articles [1-3]. This article aims to provide more detailed and specific insight into the process and methodology of the Sleep HERMES Task Force in developing a core curriculum in respiratory sleep medicine

GateFinder: projection-based gating strategy optimization for flow and mass cytometry

Motivation: High-parameter single-cell technologies can reveal novel cell populations of interest, but studying or validating these populations using lower-parameter methods remains challenging.Results: Here, we present GateFinder, an algorithm that enriches high-dimensional cell types with simple, stepwise polygon gates requiring only two markers at a time. A series of case studies of complex cell types illustrates how simplified enrichment strategies can enable more efficient assays, reveal novel biomarkers and clarify underlying biology