Models of Dependent Type Theory from Algebraic Weak Factorisation Systems

The main purpose of this dissertation is to analyse the extent to which algebraic weak factorisation systems provide models of Martin-L ̈of dependent type theory. To this end, we develop the notion of a type-theoretic awfs; this is a category equipped with an algebraic weak factorisation system and some additional structure, such that after performing a splitting procedure, a model of Martin-L ̈of dependent type theory is obtained. We proceed to construct examples of such type-theoretic awfs’s; first in the category of small groupoids, which produces the Hofmann and Streicher groupoid model. Later we make use of the machinery of uniform fibrations of Gambino and Sattler to produce type-theoretic awfs’s in Grothendieck toposes equipped with an interval object satisfying some additional properties; from this we obtain concrete examples in the categories of simplicial sets and cubical sets. We also study the notion of a normal uniform fibration, a strengthening of the notion of a uniform fibration, which allows us to address a question regarding the constructive nature of type-theoretic awfs’s. In addition, we show that the procedure of constructing type-theoretic awfs’s from uniform fibrations is functorial, thus providing a method for comparing models of dependent type theory

Models of Martin-L\"of type theory from algebraic weak factorisation systems

We introduce type-theoretic algebraic weak factorisation systems and show how they give rise to homotopy-theoretic models of Martin-L\"of type theory. This is done by showing that the comprehension category associated to a type-theoretic algebraic weak factorisation system satisfies the assumptions necessary to apply a right adjoint method for splitting comprehension categories. We then provide methods for constructing several examples of type-theoretic algebraic weak factorisation systems, encompassing the existing groupoid model and cubical sets models, as well as some models based on normal fibrationsComment: Changed title (it used to be "Type-theoretic algebraic weak factorisation systems"); rewritten introduction; fixed typos; fixed inaccuracy in Lemma 2.3 spotted by Paige North; added references. 37 page

The open abdomen in trauma and non-trauma patients : WSES guidelines

Damage control resuscitation may lead to postoperative intra-abdominal hypertension or abdominal compartment syndrome. These conditions may result in a vicious, self-perpetuating cycle leading to severe physiologic derangements and multiorgan failure unless interrupted by abdominal (surgical or other) decompression. Further, in some clinical situations, the abdomen cannot be closed due to the visceral edema, the inability to control the compelling source of infection or the necessity to re-explore (as a "planned second-look" laparotomy) or complete previously initiated damage control procedures or in cases of abdominal wall disruption. The open abdomen in trauma and non-trauma patients has been proposed to be effective in preventing or treating deranged physiology in patients with severe injuries or critical illness when no other perceived options exist. Its use, however, remains controversial as it is resource consuming and represents a non-anatomic situation with the potential for severe adverse effects. Its use, therefore, should only be considered in patients who would most benefit from it. Abdominal fascia-to-fascia closure should be done as soon as the patient can physiologically tolerate it. All precautions to minimize complications should be implemented.Peer reviewe

De miasmas a mosquitos: el pensamiento médico sobre la fiebre amarilla en Yucatán, 1890-1920 From miasmas to mosquitoes: medical thought on yellow fever in Yucatan, 1890-1920

La fiebre amarilla fue un problema de salud pública desde la época colonial debido a la frecuencia con que se presentaba en forma epidémica y a su alta letalidad. El objetivo de este trabajo es analizar el pensamiento médico y su evolución con respecto al vómito prieto entre 1890 y 1921 en Yucatán. Dos aspectos serán abordados: algunos antecedentes con respecto a la enfermedad y las ideas predominantes hasta 1881; y la propuesta de Carlos Finlay para vencer el escepticismo ante su teoría por parte de la comunidad médica. En segundo lugar se analizará la mezcla de las ideas miasmáticas y bacterianas. En tercer lugar, se mostrará cómo, a partir de la demostración de sus postulados, la mirada médica se dirigió al exterminio del mosquito transmisor de este padecimiento.<br>Yellow fever has been a public health concern since colonial days because of its frequent epidemics and high mortality rate. This analysis of medical thought about "the black vomit" in the Yucatan and the evolution of this thinking from 1890 through 1921 first addresses some of the disease's antecedents and preponderant ideas prior to 1881 as well as Carlos Finlay's efforts to convince the medical community that his theory was right. The article goes on to analyze the co-existence of miasmatic and bacterial ideas and to show how medical initiatives began focusing on eradication of the mosquito transmitter once Finlay's postulates had been demonstrated

Kidney and uro-trauma: WSES-AAST guidelines

Renal and urogenital injuries occur in approximately 10-20% of abdominal trauma in adults and children. Optimal management should take into consideration the anatomic injury, the hemodynamic status, and the associated injuries. The management of urogenital trauma aims to restore homeostasis and normal physiology especially in pediatric patients where non-operative management is considered the gold standard. As with all traumatic conditions, the management of urogenital trauma should be multidisciplinary including urologists, interventional radiologists, and trauma surgeons, as well as emergency and ICU physicians. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and the American Association for the Surgery of Trauma (AAST) kidney and urogenital trauma management guidelines

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research