Supplementing student learning with online videos has produced mixed results in respect of improving academic performance. This study proposed that these mixed results, before COVID-19, are due to most of the literature on online videos being observational studies and not taking confounding factors into account. This study applied the difference-indifferences (DID) technique, which measures treatment effects in observational studies. Using student grades data from an engineering mechanics course, the treatment effects of videos were measured 1) on the entire group that used the videos, 2) on those initially with failing and then with passing grades, and 3) on those grouped by grade percentage ranges. It was found that the videos had no effect on the entire group but did significantly affect those who had initial failing grades - specifically, grades of 40% to 49%. A main finding was that initial grades are an indication of how effective the online videos are in improving grades.

Die aanvulling van studente se leerervaring met voorafopgeneemde video's het gemengde resultate in terme van akademiese vertoning gehad. Hierdie studie stel voor dat die gemengde resultate, voor COVID-19, hoofsaaklik te wyte is aan die aard van die literatuur - die meeste studies hieroor was waarnemende studies en het nie verwarrende faktore in ag geneem nie. Hierdie studie pas die verskil-in-verskille tegniek toe; dit meet die verskille in behandeling tydens waarnemende studies. Deur bestaande data van studente se punte van 'n ingenieursmeganika vak te gebruik, is die behandelingseffekte gemeet 1) op die volledige groep wat van die video's gebruik het, 2) op die wat aanvangklik druipkategorie kandidate was wat oorgegaan het na die slaagkategorie, en 3) op groeperings aan die hand van puntreekse. Daar is gevind dat die video's geen invloed op die algehele groep gehad het nie, maar dat dit die wat aanvanklik druipkategorie kandidate was noemenswaardig beïnvloed het, veral vir studente met punte tussen 40% en 49%. Die belangrikste bevinding is dat die aanvanklike punte n aanduiding gee van die doeltreffendheid van video's om punte te verbeter.

BACKGROUND. Identifying and addressing gaps in the prevention of mother-to-child transmission of HIV (PMTCT) is required if South Africa (SA) is to achieve targets for eliminating MTCT (eMTCT). Potential PMTCT gaps that increase MTCT risk include late maternal HIV diagnosis, lack of or delayed antiretroviral therapy (ART) during pregnancy and breastfeeding, and lack of effective prophylaxis for HIV-exposed infants. OBJECTIVES. To investigate, in near real time, PMTCT gaps among HIV-infected infants in three districts of KwaZulu-Natal Province, SA. METHODS. Between May and September 2016, PMTCT co-ordinators from eThekwini, uMgungundlovu and uMkhanyakude districts received daily email notification of all HIV polymerase chain reaction (PCR)-positive results. Co-ordinators reviewed facility records for each infant to identify gaps in PMTCT care, including maternal age, timing of maternal HIV diagnosis, maternal treatment history and maternal viral load (VL) monitoring. Data were submitted via the mobile phone SMS (text message) service using Rapid Pro technology and analysed in Stata 14. RESULTS. Data on PMTCT gaps were received for 367 (91.8%) of 400 infants with HIV PCR-positive results, within a median time of 12.5 days (interquartile range (IQR) 6 - 23). The median maternal age was 25 years (IQR 22 - 30), with 48 teenage mothers (15 - 19 years). The sample size was too small to determine whether there were significant differences in PMTCT gaps between the 48 teenage mothers and 293 older (20 - 34 years) mothers. Of the mothers, 220 (60.0%) were first diagnosed prior to conception or at their first antenatal care (ANC) visit, and 127 (34.6%) at or after delivery; 137 (37.3%) transmitted HIV to their infants despite receiving >12 weeks of ART. VL results were unavailable for 70.0% of women. Only 41 (17.5%) of women known to be HIV-positive during ANC had confirmed virological suppression. No statistically significant differences in PMTCT gaps were observed between districts, owing to small sample sizes in uMgungundlovu and uMkhanyakude. CONCLUSIONS. The findings highlight the need to improve services during ANC, in particular prioritising maternal VL monitoring. We intend to use improved technology to streamline data collection and reporting towards eMTCT.

The article considers certain critical failings of the so-called "choice argument" (that is the view that, by opting to cohabit in a life partnership rather than marry or enter into a civil partnership, a life partner is not entitled to the legal benefits provided by matrimonial property law) as it was applied to opposite-sex life partnerships by the majority of the Constitutional Court in Volks v Robinson. On the basis of Canadian jurisprudence, a "contextualised choice model" is developed that distinguishes between need-based claims and those involving property disputes, and holds that the "choice argument" could at best be relevant regarding the latter category of claims, while the existence of a reciprocal duty of support is sine qua non for any need-based claim to succeed. These findings are applied to registered and unregistered domestic partnerships under the draft Domestic Partnerships Bill, 2008, with the aim of suggesting certain amendments to the Bill in the hope of ensuring a more consistent and principled legal position once the Bill is enacted.

We investigated kidney and lung alterations caused by intercellular adhesion molecule type 1 (ICAM-1) blockade after ischemia and reperfusion of hind limb skeletal muscles. Rats were submitted to ligature of the infrarenal aorta for 6 h. The animals were randomized into three groups of 6 rats each: group I, sacrificed after ischemia; group II, reperfusion for 24 h, and group III, reperfusion for 24 h after receiving monoclonal anti-ICAM-1 antibodies. At the end of the experiment, blood samples were collected for creatinine, lactate dehydrogenase, creatine phosphokinase, potassium, pH and leukocyte counts. Samples were taken from the muscles of the hind limbs and from the kidneys and lungs for histological analysis and measurement of the neutrophil infiltrate by myeloperoxidase staining. The groups did not differ significantly with regard to the laboratory tests. There were no major histological alterations in the kidneys. An intense neutrophil infiltrate in the lungs, similar in all groups, was detected. Myeloperoxidase determination showed that after reperfusion there was significantly less retention of polymorphonuclear neutrophils in the muscles (352 ± 70 vs 1451 ± 235 × 10² neutrophils/mg; P<0.01) and in the kidneys (526 ± 89 vs 852 ± 73 × 10² neutrophils/mg; P<0.01) of the animals that received anti-ICAM-1 before perfusion compared to the group that did not. The use of anti-ICAM-1 antibodies in this experimental model minimized neutrophil influx, thus reducing the inflammatory process, in the muscles and kidneys after ischemia and reperfusion of the hind limbs.