The accessibility rank of weak equivalences

We study the accessibility properties of trivial cofibrations and weak equivalences in a combinatorial model category and prove an estimate for the accessibility rank of weak equivalences. In particular, we show that the class of weak equivalences between simplicial sets is finitely accessible.Comment: The main result is improved and its proof is simplified. To appear in Theory and Applications of Categories. 15 page

An Evaluated Certification Services System for the German National Root CA - Legally Binding and Trustworthy Transactions in E-Business and E-Government

National Root CAs enable legally binding E-Business and E-Government transactions. This is a report about the development, the evaluation and the certification of the new certification services system for the German National Root CA. We illustrate why a new certification services system was necessary, and which requirements to the new system existed. Then we derive the tasks to be done from the mentioned requirements. After that we introduce the initial situation at the beginning of the project. We report about the very process and talk about some unfamiliar situations, special approaches and remarkable experiences. Finally we present the ready IT system and its impact to E-Business and E-Government.Comment: 6 pages; 1 figure; IEEE style; final versio

A comparison of three numerical methods for updating regressions.

Three numerical procedures are presented for updating regressions. All three methods are based on QR factorization, but after that they use different philosophies to update the regression coefficients. Elden's algorithm updates using only the triangular matrix R. This procedure does not use orthogonal transformations, but it uses hyperbolic rotations. The modified Gram-Schmidt QR process is used by Gragg- Leveque-Trangenstein's method where the matrix with orthonormal columns is stored and updated. Chan's algorithm computes a column permutation n and a QR factorization of a matrix A such that a rank deficiency of A will be revealed. Although the three methods are based on different ideas and can be used for different purposes their comparison shows that Chan's algorithm is the only accurate one in the rank deficient case, and that Gragg-Leveque-Trangenstein's method is the cheapest and the most stable.http://archive.org/details/comparisonofthre00raptLieutenant Commander, Hellenic NavyApproved for public release; distribution is unlimited

CT findings and patterns of e-cigarette or vaping product use-associated lung injury: A multicenter cohort of 160 cases

BACKGROUND: e-Cigarette or vaping-induced lung injury (EVALI) causes a spectrum of CT lung injury patterns. Relative frequencies and associations with vaping behavior are unknown. RESEARCH QUESTION: What are the frequencies of imaging findings and CT patterns in EVALI and what is the relationship to vaping behavior? STUDY DESIGN AND METHODS: CT scans of 160 subjects with EVALI from 15 institutions were retrospectively reviewed. CT findings and patterns were defined and agreed on via consensus. The parenchymal organizing pneumonia (OP) pattern was defined as regional or diffuse ground-glass opacity (GGO) ± consolidation without centrilobular nodules (CNs). An airway-centered OP pattern was defined as diffuse CNs with little or no GGO, whereas a mixed OP pattern was a combination of the two. Other patterns included diffuse alveolar damage (DAD), acute eosinophilic-like pneumonia, and pulmonary hemorrhage. Cases were classified as atypical if they did not fit into a pattern. Imaging findings, pattern frequencies, and injury severity were correlated with substance vaped (marijuana derives [tetrahydrocannabinol] [THC] only, nicotine derivates only, and both), vaping frequency, regional geography, and state recreational THC legality. One-way analysis of variance, χ RESULTS: A total of 160 patients (79.4% men) with a mean age of 28.2 years (range, 15-68 years) with EVALI underwent CT scan. Seventy-seven (48.1%), 15 (9.4%), and 68 (42.5%) patients admitted to vaping THC, nicotine, or both, respectively. Common findings included diffuse or lower lobe GGO with subpleural (78.1%), lobular (59.4%), or peribronchovascular (PBV) sparing (40%). Septal thickening (50.6%), lymphadenopathy (63.1%), and CNs (36.3%) were common. PBV sparing was associated with younger age (P = .02). Of 160 subjects, 156 (97.5%) had one of six defined patterns. Parenchymal, airway-centered, and mixed OP patterns were seen in 89 (55.6%), 14 (8.8%), and 32 (20%) patients, respectively. Acute eosinophilic-like pneumonia (six of 160, 3.8%), DAD (nine of 160, 5.6%), pulmonary hemorrhage (six of 160, 3.8%), and atypical (four of 160, 2.5%) patterns were less common. Increased vaping frequency was associated with more severe injury (P = .008). Multivariable analysis showed a negative association between vaping for \u3e 6 months and DAD pattern (P = .03). Two subjects (1.25%) with DAD pattern died. There was no relation between pattern and injury severity, geographic location, and state legality of recreational use of THC. INTERPRETATION: EVALI typically causes an OP pattern but exists on a spectrum of acute lung injury. Vaping habits do not correlate with CT patterns except for negative correlation between vaping \u3e 6 months and DAD pattern. PBV sparing, not previously described in acute lung injury, is a common finding

Gut dysfunction in patients with multiple sclerosis and the role of spinal cord involvement in the disease.

Bowel and bladder symptoms are highly prevalent in patients with multiple sclerosis (MS). Bladder dysfunction (affecting 75% of these patients) is caused by disease in the spinal cord, whilst the pathophysiology of bowel dysfunction is unknown. Pathways regulating both the organs lie in close proximity to the spinal cord, and coexistence of their dysfunction might be the result of a common pathophysiology. If so, the prevalence of bladder symptoms should be greater in patients with MS and bowel symptoms. This hypothesis is tested in the study. We also evaluated how patient-reported symptoms quantify bowel dysfunction

A survey of school’s preparedness for managing anaphylaxis in pupils with food allergy

Allergic diseases are on the increase and can affect the child's well-being. The aim of this survey was to assess regional schools' preparedness in dealing with anaphylaxis following the publication of national and international guidelines for schools in 2014. The survey was developed in 2015 and distributed to schools in Cumbria, North West England, UK between 2015 and 2016. Only 47% of the respondents (95% CI, 39-57%) felt confident to manage anaphylaxis. Schools without allergic pupils were significantly less likely to have a standard management protocol in place for emergencies compared to those with allergic pupils (p < 0.001). The majority of the schools indicated that further training was needed (81% (95% CI, 74-88%).Conclusion: At the time of the survey, schools' preparedness in the region, did not meet safety standards recommended by national and international organisations. Although schools have shown eagerness in accessing training in the management of anaphylaxis, tailored training for schools is not yet widely available. There is now an urgent need to design feasible training strategies that create a safe environment for allergic pupils across all UK schools.What is Known:• One quarter of the severe allergic reactions take place for the first time while at school with some of them being fatal.• School staff is ill-prepared in the management of anaphylaxis. Access to formal training is not widely available.What is New:• School staff remains unconfident in managing the severe allergic child.Training in the management of anaphylaxis is scarce, and when available, it does not offer the required depth to cover the holistic needs of allergic pupils.• Schools would welcome generic adrenaline autoinjectors and a national policy with central funding which would describe step by step the necessary measures for the management of anaphylaxis

Liver Transplantation and Surgery in the Management of Hepatocellular Carcinoma

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MRI of Suspected Appendicitis During Pregnancy: Interradiologist Agreement, Indeterminate Interpretation and the Meaning of Non-Visualization of the Appendix

Objective: To determine the degree of interradiologist agreement between the MRI features of appendicitis during pregnancy, the outcomes associated with an indeterminate interpretation and the negative predictive value of non-visualization of the appendix. Methods: Our study was approved by the institutional review board at the Washington University in St. Louis, Missouri (WUStL) and was HIPAA (Health Insurance Portability and Accountability Act of 1996)-compliant. The informed consent requirement was waived. Cases of suspected appendicitis during pregnancy evaluated using MRI were retrospectively identified using search queries. Scans were re-reviewed by two radiologists (7 and 9 years experience, respectively) to evaluate the interradiologist agreement of different MRI features of appendicitis during pregnancy (visualization of the appendix, appendiceal diameter, appendiceal wall thickening, periappendiceal fat stranding, fluid-filled appendix and periappendiceal fluid). The radiologists were blinded to patient outcome, patient intervention, laboratory data, demographic data and the original MRI reports. Clinical outcomes were documented by surgical pathology or clinical observation. Interradiologist agreement was analysed using Cohen’s κ, while patient demographic and clinical data was analysed using Student\u27s t-testing. Results: 233 females with suspected appendicitis during pregnancy were evaluated using MRI over a 13-year period (mean age, 28.4 years; range, 17–38 years). There were 14 (6%) positive examinations for appendicitis during pregnancy, including 1 patient whose MRI was interpreted as negative, proven by surgical pathology. The presence of periappendiceal soft-tissue stranding and the final overall impression had the most interradiologist agreement (к = 0.81–1). There were no pregnant patients found to have acute appendicitis who had an indeterminate MR interpretation or when the appendix could not be visualized. Conclusion: The final impression by the two retrospectively reviewing radiologists of MR examinations performed for suspected appendicitis during pregnancy had near-perfect agreement. In patients where the appendix could not be visualized or in patients that were interpreted as indeterminate, no patients had acute appendicitis. Advances in Knowledge: MR impression for suspected appendicitis in the pregnant patient has high interradiologist agreement, and a non-visualized appendix or lack of inflammatory findings at the time of MR, reliably excludes surgical appendicitis