This study provides with original data sets on the physiology of the unicellular diazotrophic cyanobacterium Crocosphaera watsonii WH8501, maintained in continuous culture in conditions of obligate diazotrophy. Cultures were exposed to a 12:12 light-dark regime, representative of what they experience in nature and where growth is expected to be balanced. Nitrogen and carbon metabolism were monitored at high frequency and their dynamics was compared with the cell cycle. Results reveal a daily cycle in the physiological and biochemical parameters, tightly constrained by the timely decoupled processes of N(2) fixation and carbon acquisition. The cell division rate increased concomitantly to carbon accumulation and peaked 6 h into the light. The carbon content reached a maximum at the end of the light phase. N(2) fixation occurred mostly during the dark period and peaked between 9 and 10 h into the night, while DNA synthesis, reflected by DNA fluorescence, increased until the end of the night. Consequently, cells in G1- and S-phases present a marked decrease in their C:N ratio. Nitrogen acquisition through N(2) fixation exceeded 1.3- to 3-fold the nitrogen requirements for growth, suggesting that important amounts of nitrogen are excreted even under conditions supposed to favour balanced, carbon and nitrogen acquisitions.

We propose a generalization of non-commutative geometry and gauge theories based on ternary Z 3 -graded structures. In the new algebraic structures we define, we leave all products of two entities free, imposing relations on ternary products only. These relations reflect the action of the Z 3 -group, which may be either trivial, i.e. abc = bca = cab, generalizing the usual commutativity, or non-trivial, i.e. abc = jbca, with j = e (2πi)/3 . The usual Z 2 -graded structures such as Grassmann, Lie and Clifford algebras are generalized to the Z 3 -graded case. Certain suggestions concerning the eventual use of these new structures in physics of elementary particles are exposed.

Bile duct injury (BDI) is a dangerous complication of cholecystectomy, with significant postoperative sequelae for the patient in terms of morbidity, mortality, and long-term quality of life. BDIs have an estimated incidence of 0.4–1.5%, but considering the number of cholecystectomies performed worldwide, mostly by laparoscopy, surgeons must be prepared to manage this surgical challenge. Most BDIs are recognized either during the procedure or in the immediate postoperative period. However, some BDIs may be discovered later during the postoperative period, and this may translate to delayed or inappropriate treatments. Providing a specific diagnosis and a precise description of the BDI will expedite the decision-making process and increase the chance of treatment success. Subsequently, the choice and timing of the appropriate reconstructive strategy have a critical role in long-term prognosis. Currently, a wide spectrum of multidisciplinary interventions with different degrees of invasiveness is indicated for BDI management. These World Society of Emergency Surgery (WSES) guidelines have been produced following an exhaustive review of the current literature and an international expert panel discussion with the aim of providing evidence-based recommendations to facilitate and standardize the detection and management of BDIs during cholecystectomy. In particular, the 2020 WSES guidelines cover the following key aspects: (1) strategies to minimize the risk of BDI during cholecystectomy; (2) BDI rates in general surgery units and review of surgical practice; (3) how to classify, stage, and report BDI once detected; (4) how to manage an intraoperatively detected BDI; (5) indications for antibiotic treatment; (6) indications for clinical, biochemical, and imaging investigations for suspected BDI; and (7) how to manage a postoperatively detected BDI.

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Background: Folfirinox (FFX) and gemcitabine/nab-paclitaxel (GN) are both standard first-line treatments in patients with metastatic pancreatic cancer (mPC). However, data comparing these two chemotherapeutic regimens and their sequential use remain scarce. Methods: Data from two independent cohorts enrolling patients treated with FFX ( n = 107) or GN ( n = 109) were retrospectively pooled. Primary endpoint was overall survival (OS). Progression-free survival (PFS) was the secondary endpoint. A propensity score based on age, gender, performance status (PS), and presence of liver metastases was used to make groups comparable. Results: In the whole study population, OS was significantly higher in FFX (14 months; 95% CI: 10–21) than in GN groups (9 months; 95% CI: 8–12) before ( p = 0.008) and after ( p = 0.021) adjusting for age, number of metastatic sites, liver metastases, peritoneal carcinomatosis and CA19.9 level at baseline. PFS tends to be higher in FFX (6 months) than GN groups (5 months; p = 0.053). After matching ( n = 49/group), patients were comparable for all baseline characteristics including PS. In the matched population, there was a trend toward greater OS in patients treated with FFX (HR = 0.67; p = 0.097). However, survival in each group was not solely a result of the first-line regimen. The proportion of patients who were fit for GN after FFX failure (FFX–GN sequence) was higher (46.9%) than the reverse sequence (20.4%; p = 0.01), which suggests a higher feasibility for the FFX–GN sequence. Corresponding median OS were 19 months versus 9.5 months, respectively ( p = 0.094). Conclusion: This study shows greater OS with FFX than with GN in patients with mPC. GN after FFX failure appears more feasible than the reverse sequence.

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