Ternary Syndrome Decoding with Large Weight

The Syndrome Decoding problem is at the core of many code-based cryptosystems. In this paper, we study ternary Syndrome Decoding in large weight. This problem has been introduced in the Wave signature scheme but has never been thoroughly studied. We perform an algorithmic study of this problem which results in an update of the Wave parameters. On a more fundamental level, we show that ternary Syndrome Decoding with large weight is a really harder problem than the binary Syndrome Decoding problem, which could have several applications for the design of code-based cryptosystems

Oxygen carrying capacity of salvaged blood in patients undergoing off-pump coronary artery bypass grafting surgery : a prospective observational study

BACKGROUND: Intraoperative cell salvage (ICS), hereby referred to ‘mechanical red cell salvage’, has been widely used and proven to be an effective way to reduce or avoid the need for allogeneic red blood cells (RBCs)transfusion and its associated complications in surgeries involving major blood loss. However, little is known about the influence of this technique on the functional state of salvaged RBCs. Furthermore, there are no articles that describe the change of free hemoglobin (fHb) in salvage blood during storage, which is a key index of the quality control of salvaged blood. Therefore, in this study, the influence of ICS on the function of salvaged RBCs and the changes of salvaged RBCs during storage were studied with respect to the presence of oxyhemoglobin affinity (recorded as a P(50) value) and the level of 2, 3-diphosphoglycerate (2, 3-DPG) and fHb by comparing salvaged RBCs with self-venous RBCs and 2-week-old packed RBCs. METHODS: Fifteen patients undergoing off-pump coronary artery bypass grafting (OPCAB) surgery were enrolled. Blood was collected and processed using a Dideco Electa device. The level of P(50), 2, 3-DPG and fHB from salvaged RBCs, venous RBCs and 2-week-old packed RBCs was measured. We also measured the changes of these indicators among salvaged RBCs at 4 h (storage at 21–24 °C) and at 24 h (storage at 1–6 °C). RESULTS: The P(50) value of salvaged RBCs at 0 h (28.77 ± 0.27 mmHg) was significantly higher than the value of venous RBCs (27.07 ± 0.23 mmHg, p = 0.000) and the value of the 2-week-old packed RBCs (16.26 ± 0.62 mmHg, p = 0.000). P(50) value did not change obviously at 4 h (p = 0.121) and 24 h (p = 0.384) compared with the value at 0 h. The 2, 3-DPG value of salvaged RBCs at 0 h (17.94 ± 6.91 μmol/g Hb) was significantly higher than the value of venous RBCs (12.73 ± 6.52 mmHg, p = 0.007) and the value of the 2-week-old packed RBCs (2.62 ± 3.13 mmHg, p = 0.000). The level of 2, 3-DPG slightly decreased at 4 h (p = 0.380) and 24 h (p = 0.425) compared with the value at 0 h. Percentage of hemolysis of the salvaged blood at 0 h(0.51 ± 0.27 %) was significantly higher than the level of venous blood (0.07 ± 0.05 %, p = 0.000) and the value of 2-week-old packed RBCs (0.07 ± 0.05 %, p = 0.000), and reached 1.11 ± 0.42 % at 4 h (p = 0.002) and 1.83 ± 0.77 % at 24 h (p = 0.000). CONCLUSIONS: The oxygen transport function of salvaged RBCs at 0 h was not influenced by the cell salvage process and was better than that of the venous RBCs and 2-week-old packed RBCs. At the end of storage, the oxygen transport function of salvaged RBCs did not change obviously, but percentage of hemolysis significantly increased

How COVID-19 impacted risky sexual behaviours of female sex workers in Senegal and its wider implications: Evidence from a cohort study

Background: The COVID-19 pandemic has the potential to be the most severe and long-lasting economic shock experienced by female sex workers (FSWs) globally due to the high and close contact nature of the profession. Given that there is a positive income premium attached to unprotected sex, FSWs may resort to adopting risky sexual behaviours as a means to cope with the decreased earnings resulting from COVID-19. / Methods: We used data from a cohort study of around 600 Senegalese FSWs in Dakar, Senegal. During the COVID-19 pandemic in June-July 2020, we elicited respondents’ perceptions of how COVID-19 has affected them. We also compared FSWs’ income and sexual behaviours in 2020 with that of previous survey waves in 2015 and 2017. For continuous variables, the mean, median, interquartile range (IQR), 10th and 90th percentiles were reported. A t-test was also carried out to test the differences between the means in 2017 and 2020. For categorical variables, bar charts were shown. Condom use was elicited via the list experiment method to overcome social desirability bias. Heterogeneity analyses were carried out to identify the channels through which COVID-19 affected condom use. / Findings: COVID-19 led to a 70·0% reduction in the number of clients seen in a week from 2017 levels. The steep fall in the number of clients led to a reduction in sex work earnings by 50·3%. Estimated condom use prevalence with the last client was similar in 2015 and 2017, but decreased by 13·1%-pts during the COVID-19 pandemic (p=0·014), corresponding to a drop of 16·8% compared to 2017. Condom use decline was concentrated amongst asset-poor FSWs (22·7%-pts drop (p=0·004); 27·0% reduction in condom use from 2017 levels). However, self-reported STI symptoms did not increase. Furthermore, a substantial proportion of FSWs reported that they have reduced visits to health facilities because of COVID-19, but there was no evidence that this was associated with decreased condom use. Mental health of FSWs has deteriorated, while experience of violence from clients or the police has remained largely unchanged. / Interpretation: Condom use has likely to have fallen to alleviate the economic shock brought about by COVID-19. While the plunge in the number of clients may have offset the transmission of HIV and other STIs for now, it remains to be seen whether condom use would resume once business improves, especially if the crisis were to be prolonged. Given the potential public health issue this may create, policies targeting FSWs to dampen the adverse economic impact of the COVID-19 crisis should urgently be considered as a strategy to prevent the transmission of HIV and other STIs

Prise en charge des fistules entéro-cutanées post-opératoires au Service de Chirurgie Générale du CHU A Le Dantec.

Le but de notre étude était de rapporter notre expérience dans la prise en charge des fistules entéro-cutanées post-opératoires (FECPO). Il s’agissait d’une étude rétrospective qui s’est déroulée au CHU A Le Dantec sur 10 ans (2000- 2010). Les critères d’inclusion étaient les patients qui présentaient une FEC PO durant la période d’étude. Les paramètres étudiés étaient les suivants : le terrain, l’intervention initiale, les circonstances de découverte, le délai d’apparition et les caractéristiques de la FEC PO, l’évolution sous traitement médical, les indications et les résultats du traitement chirurgical. Ont été inclus dans l’étude 25 patients d’âge moyen de 30 ans. Il s’agissait de 17 hommes et de 8 femmes avec un sex-ratio de 2,1. Six patients (24%) avaient au minimum un antécédent de laparotomie. Sept cas de dénutrition (28%) ont été notés. L’intervention initiale concernait le grêle dans 40% des cas et le côlon dans 32% des cas ; elle avait été réalisée dans un contexte d’urgence chez 17 patients (68%). Des incidents et difficultés opératoires avaient été rapportés chez 7 patients (28%). Les circonstances de découverte de la fistule étaient à type d’écoulement anormal de liquide digestif à travers l’incision dans 72% des cas. Les fistules étaient semi-précoces dans 56% des cas ; elles étaient iléales dans 13 cas (52%), et de bas débit dans 19 cas (76%). Sous traitement médical, 15 patients (60%) avaient évolué vers une guérison spontanée. Un traitement chirurgical était indiqué chez 9 patients (36%) avec évolution favorable dans 66 % des cas. La mortalité globale était de 12% (n=3), par défaillance multi viscérale. Dans notre service, les FEC PO sont surtout des complications du sujet jeune, de type semiprécoce, de siège invariablement iléal et colique, à bas débit et à trajet latéral qui guérissent majoritairement sous traitement médical dans un délai moyen de 3 semaines. Le traitement chirurgical est surtout indiqué devant le sepsis intra abdominal qui explique la mortalité rapportée.Mots clés : Fistule entéro-cutanée, traitement, chirurgie

Improvement of Binary and Non Binary Statistical Decoding Algorithm

International audienc

Effective coupling of phenol adsorption and photodegradation at the surface of micro-and mesoporous TiO2-activated carbon materials

International audienceNovel titania supported activated carbon catalysts were prepared by a straightforward titania coating route of a microporous activated carbon (AC) derived from shea nut shells, and investigated in phenol photocatalytic degradation. The proposed coating method enables a fixation of the preformed titania anatase nanoparticles (TiO2 NPs) in the external porosity thus allowing their accessibility towards UV irradiation, without causing any reduction of the AC specific area. Interestingly, the coating treatment reshapes the porous texture of the as-prepared TiO2–AC composite materials resulting in an improvement of the adsorption capacity and the formation of an additional mesoporosity on the TiO2-AC surface. Photocatalytic experiments carried out in a batch reactor led to 97% elimination rate of phenol in an aqueous solution with the AC catalysts containing TiO2 NPs in the range from 11 to 34 wt%. The photodegradation performance of the TiO2–AC catalysts was maintained over several successive cycles, without the need of any regeneration treatment. Considering both the textural and microstructural features of the composite materials and their associated phenol removal kinetics, in this paper, we provide new insights into phenol photodegradation pathway involving an effective coupling of adsorption and photodegradation functionalities, resulting in a photo-assisted regeneration mechanism of the catalyst