Determination of precipitate strength in aluminium alloy 6056-T6 from transmission electron microscopy in situ straining data

International audienceThe transmission electron microscopy in-situ straining technique is employed to measure the breaking angles of strengthening precipitates in aluminium alloy 6056-T6 as they are sheared by dislocations. The experimental determination of the character of bowed dislocation segments when dislocations are pinned on precipitates allows us to calculate the corresponding line tensions. From this, the maximum forces F-m that precipitates can sustain before being sheared by dislocations are deduced. It is suggested that F-m may be regarded as a quantitative parameter which includes the effects of the various strengthening mechanisms operative in precipitation-hardened alloys. An attempt is made to relate the maximum force calculated from in-situ straining data to the macroscopic yield strength of the material

Naturally acquired immune responses to malaria vaccine candidate antigens MSP3 and GLURP in Guahibo and Piaroa indigenous communities of the Venezuelan Amazon

BACKGROUND: Malaria transmission in most of Latin America can be considered as controlled. In such a scenario, parameters of baseline immunity to malaria antigens are of specific interest with respect to future malaria eradication efforts. METHODS: A cross-sectional study was carried out in two indigenous population groups in Amazonas/Venezuela. Data from the regional malaria documentation system were extracted and participants from the ethnic groups of the Guahibo (n = 180) and Piaroa (n = 295) were investigated for the presence of Plasmodium parasites and naturally acquired antibodies to Plasmodium falciparum antigens in serum. The GMZ2 vaccine candidate proteins MSP3 and GLURP were chosen as serological markers. RESULTS: The incidence of P. falciparum in both communities was found to be less than 2%, and none of the participants harboured P. falciparum at the time of the cross-sectional. Nearly a quarter of the participants (111/475; 23,4%) had positive antibody titres to at least one of the antigens. 53/475 participants (11.2%) were positive for MSP3, and 93/475 participants (19.6%) were positive for GLURP. High positive responses were detected in 36/475 participants (7.6%) and 61/475 participants (12.8%) for MSP3 and GLURP, respectively. Guahibo participants had significantly higher antibody titres than Piaroa participants. CONCLUSIONS: Considering the low incidence of P. falciparum, submicroscopical infections may explain the comparatively high anti-P. falciparum antibody concentrations

Synthesis and Antiplasmodial Activity of New IndoloneN-Oxide Derivatives

Synthesis and Antiplasmodial Activity of New IndoloneN-Oxide Derivative

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Anthocyanin in grape skins during maturation of <em>Vitis vinifera</em> L. cv. Cabernet Sauvignon and Merlot noir from different Bordeaux terroirs

Three varieties of red grapes have been analysed on the basis of their anthocyanin content to search a relation between this parameter and selected terroirs. For that, we compared their anthocyanin evolution during maturation. Then we analysed by HPLC the anthocyanin content of grapes at maturity and of their corrresponding wines. So, we established a comparison between potential anthocyanins in grapes and in corresponding wines. These observations permitted to occur some characteristics to these varieties and to evaluate the impact of terroir on grape skins anthocyanin composition