Mutation of Directed Graphs -- Corresponding Regular Expressions and Complexity of Their Generation

Directed graphs (DG), interpreted as state transition diagrams, are traditionally used to represent finite-state automata (FSA). In the context of formal languages, both FSA and regular expressions (RE) are equivalent in that they accept and generate, respectively, type-3 (regular) languages. Based on our previous work, this paper analyzes effects of graph manipulations on corresponding RE. In this present, starting stage we assume that the DG under consideration contains no cycles. Graph manipulation is performed by deleting or inserting of nodes or arcs. Combined and/or multiple application of these basic operators enable a great variety of transformations of DG (and corresponding RE) that can be seen as mutants of the original DG (and corresponding RE). DG are popular for modeling complex systems; however they easily become intractable if the system under consideration is complex and/or large. In such situations, we propose to switch to corresponding RE in order to benefit from their compact format for modeling and algebraic operations for analysis. The results of the study are of great potential interest to mutation testing

Ultrafast doublon dynamics in photoexcited 1T1T-TaS2{\mathrm{TaS}}_{2}

Strongly correlated materials exhibit intriguing properties caused by intertwined microscopic interactions that are hard to disentangle in equilibrium. Employing nonequilibrium time-resolved photoemission spectroscopy on the quasi-two- dimensional transition-metal dichalcogenide 1T-TaS2, we identify a spectroscopic signature of doubly occupied sites (doublons) that reflects fundamental Mott physics. Doublon-hole recombination is estimated to occur on timescales of electronic hopping ℏ/J≈14 fs. Despite strong electron-phonon coupling, the dynamics can be explained by purely electronic effects captured by the single-band Hubbard model under the assumption of weak hole doping, in agreement with our static sample characterization. This sensitive interplay of static doping and vicinity to the metal- insulator transition suggests a way to modify doublon relaxation on the few- femtosecond timescale

EVALUATION OF A HAEMOSTATIC AGENT IN RABBITS

Topical hemostatic agents are applied locally to areas of injured vascular endothelium to control local bleeding. Ankaferd Blood Stopper (ABS) has gained approval in Turkey and Bosnia-Herzegovina as a topical haemostatic agent for external post-surgical and post-dental surgery bleeding. The safety of topical use of ABS has been demonstrated in numerous in vitro and in vivo animal models, as well as in a clinical Phase I trial in humans. ABS, besides its haemostatic activity, also has in vitro anti-infectious and anti-neoplastic effects. To assess potential detrimental effects of intravenous administration of ABS into intact systemic circulation in a rabbit experimental model, one milliliter of ABS was administered intravenously into the systemic circulation of twelve rabbits which were included in the study via the marginal ear vein. Animals were observed for 1 hr before euthanasia was performed by administering 40 mg of intracardiac suxamethonium chloride. In the event of death (cardiopulmonary arrest) before the end of the planned observation period of 60 minutes, time of death was recorded and histopathological examination of the liver and spleen was commenced. Ten rabbits were alive by the end of the planned observation period, without showing any clear signs of discomfort, whereas two animals died within five minutes after systemic administration of intravenous ABS. Postmortem histopathological examination of the livers and spleens of all animals’ revealed findings consistent with hepatic venous outflow obstruction. Systemic intravascular administration of ABS into intact vascular endothelium should never be performed in any setting. Further experimental and clinical studies on this liquid hemostatic agent should proceed by accepting ABS as purely a topical haemostatic agent, to be applied solely to areas of injured vascular endothelium

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

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

Problem of Unemployment in the Institution of the Qadi

From the classical age onwards, a problem of unemployment emerged in the town qadi institutions due to the job rotation system implemented in the Ottoman Ilmiyye as well as the increase in the number of candidates waiting to be appointed to existing posts. This problem became even more acute in the postclassical age together with the widely used niyabet system. With the declaration of the Tanzimat, the iltizam system was abolished, and this led to the termination of income sharing between the qadi and the naib. The period of Seyhulislam m Mesrebzade Arif Efendi, who adopted the Tanzimat reforms, was important for the Ilmiyye. The Nuvvab Nizamname, which was passed in 1855, enabled the centralization of the status of the naib, and following this, Muallimhane-i Nuvvab, a school for training naibs, was established. All these developments initiated the transition from the institution of the qadi to that of the naib, eventually leading to the weakening of the qadi institution. The passing of the Tevcihat Nizamname also made significant contributions to solving the unemployment problem

Problem of Unemployment in the Institution of the Qadi

From the classical age onwards, a problem of unemployment emerged in the town qadi institutions due to the job rotation system implemented in the Ottoman Ilmiyye as well as the increase in the number of candidates waiting to be appointed to existing posts. This problem became even more acute in the postclassical age together with the widely used niyabet system. With the declaration of the Tanzimat, the iltizam system was abolished, and this led to the termination of income sharing between the qadi and the naib. The period of Seyhulislam m Mesrebzade Arif Efendi, who adopted the Tanzimat reforms, was important for the Ilmiyye. The Nuvvab Nizamname, which was passed in 1855, enabled the centralization of the status of the naib, and following this, Muallimhane-i Nuvvab, a school for training naibs, was established. All these developments initiated the transition from the institution of the qadi to that of the naib, eventually leading to the weakening of the qadi institution. The passing of the Tevcihat Nizamname also made significant contributions to solving the unemployment problem