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关键词： Mathematics   general  

摘要： We show that if V is a vertex operator algebra such that all the irreducible ordinary V-modules are C-1-cofinite and all the grading-restricted generalized Verma modules for V are of finite length, then the category of finite length generalized V-modules has a braided tensor category structure. By applying the general theorem to the simple affine vertex operator algebra (resp. superalgebra) associated to a finite simple Lie algebra (resp. Lie superalgebra) g at level k and the category K(L)k (g) of its finite length generalized modules, we discover several families of KLk (g) at non-admissible levels k, having braided tensor category structures. In particular, KLk (g) has a braided tensor category structure if the category of ordinary modules is semisimple or more generally if the category of ordinary modules is of finite length. We also prove the rigidity and determine the fusion rules of some categories KLk(g), including the category KL-1(sl(n)). Using these results, we construct a rigid tensor category structure on a full subcategory of KL1(sl(n vertical bar m)) consisting of objects with semisimple Cartan subalgebra actions.

摘要： Background. The International Association for the Study of Lung Cancer (IASLC) N classifications, which depend on the location and involvement of the lymph nodes, provide accurate prognoses. This study validated the efficiency of classifications using a single-institution dataset and proposed a modified system based on 5-level N1 node dissection. Methods. From January 2005 to December 2014, 1851 patients with completely resected non-small cell lung cancer were reviewed. According to the IASLC recommendations, N1 is further subdivided into N1a (single) and N1b (multiple), N2 is divided into N2a1 (single station without N1), N2a2 (single station with N1), and N2b (multiple station). Additionally, we evaluated dividing N0 into N0a (with level 13/14 examination) and N0b (without level 13/14 examination), and N1 into N1a* (only level 13/14 positive) and N1b* (level 10-12 positive). Overall survival was also compared. Results. Multivariate analysis showed that the N classifications recommended by the IASLC and those proposed and evaluated by this study could both significantly predict the prognoses of patients (p < 0.001, respectively). There was no significant difference in survival between N1b and N1a (hazard ratio [HR] 1.049, p = 0.83) and N2a1 and N1b (HR 1.314, p = 0.261);however, there were significant differences between N0a and N0b (HR 1.778, p < 0.001) and N1a* and N1b* (HR 2.014, p = 0.019). The survival curve of N1a* overlapped N0b (HR 0.997, p = 0.991), and N2a1 overlapped N1b* (HR 0.842, p = 0.444). Conclusion. More detailed nodal information is required to facilitate future revisions of N staging.

关键词： COVID-19   SARS-CoV-2   Pneumonia   Respiratory failure   Computed tomography  

摘要： Purpose To investigate CT patterns of COVID-19 pneumonia associated with respiratory failure (RF) focused on the distribution of lesions. Materials and methods Eighty-five patients with COVID-19 pneumonia were reviewed. CT findings were classified as follows: Type A;patchy ground glass attenuation (GGA) with/without air-space consolidation, Type B;non-segmental GGA with/without air-space consolidation in both the central and peripheral lung portions especially with subpleural spare, and Type C;non-segmental GGA with/without air-space consolidation predominantly distributed in the peripheral lung portion without subpleural spare. We analyzed CT patterns and clinical factors associated with RF, including age categories. Results The number of patients with Type A, B and C was 31 (37%), 24 (28%) and 30 (35%), respectively. Type C and hypertension were independently associated with RF. On comparing between Types B and C, the frequency of traction bronchiectasis was higher in Type C than in Type B (P < 0.001). The ratio of Type C in patients >= 65 years old (66%) was higher than in patients < 40 years old (P < 0.001) and 40-49 years old (P = 0.001). Conclusion The Type C, increasing with age, was associated with RF. Traction bronchiectasis in the lesion was more frequent in Type C than in Type B. Secondary abstract A lesion adjacent to the pleura and hypertension is associated with respiratory failure in patients with COVID-19. The frequency of a lesion adjacent to the pleura increased with age. The distribution of lesions is a useful parameter to predict respiratory failure.

摘要： Objective This study aimed to estimate trends in cardiovascular disease risk factors by BMI category among adults in England (n = 115,860). Methods Risk factors included cigarette smoking, hypertension, total diabetes, and raised total cholesterol. Risk factor prevalence was computed in the following four 4-year time periods: 2003-2006;2007-2010;2011-2014;and 2015-2018. Change was computed as the difference between the first and last time periods, expressed in percentage points (PP). Results Hypertension remained at a stable level among men with normal weight but decreased among men with obesity (-4.1 PP;95% CI: -7.1 to -1.0). Total diabetes remained at a stable level among adults with normal weight but increased among adults with obesity (men: 3.5 PP, 95% CI: 1.2 to 5.7;women: 3.6 PP, 95% CI: 1.8 to 5.4). Raised total cholesterol decreased in all BMI groups but fell more sharply among women with obesity (-21 PP;95% CI: -25 to -17) versus their counterparts with normal weight (-16 PP;95% CI: -18 to -14). Conclusions Greater reductions in hypertension and raised total cholesterol among adults with overweight and obesity partially reflect improvements in screening, treatment, and control among those at highest cardiovascular risk. Higher levels of risk factor prevalence among adults with overweight and obesity, in parallel with rising diabetes, highlight the importance of national prevention efforts to combat the public health impact of excess adiposity.

关键词： Brand extension   Event-related potentials   N270   Time-frequency analysis  

摘要： In this paper, neural features influenced by brand familiarity and category were investigated in a brand extension experiment by using conventional event-related potentials (ERPs) and time-frequency analysis. Twenty-four participants were required to decide whether to accept the extension of one brand (stimulus 1) to a certain product category (stimulus 2) in a 2 familiarity x 2 category paradigm. Stimulus 1 consisted of household appliance brands that had different degrees of familiarity (high familiarity vs. low familiarity) to a certain participant, and stimulus 2 consisted of two categories of products (high conflict vs. low conflict). Twenty-two sets of valid data were used for data analysis. We found greater N270 amplitudes in the low-familiarity brand condition and in the high-conflict product category condition, which meant that the participants had to devote more cognitive resources when the brand was less familiar and felt more conflict when the brand was extended to the high-conflict product category. According to the time-frequency analysis results, brand familiarity and product category were found to have a significant effect on the amplitude of theta-band power (4-7.5 Hz) at frontal electrodes in the time period of 270 & minus;340 ms. This result indicated that the activity of individual nodes of the language processing networks increased when the extension product category was mismatched with respect to the brand name and that the related memory of the brand was activated and the long-term memory was extracted when the participants faced the high-familiarity brand extension. The study provides an insightful view of how brand familiarity and category influence consumers' cognitive processes regarding brand extension. (c) 2020 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.

关键词： Monomial algebras   Gorenstein algebras   Silting objects   Singularity categories   Tilting objects  

摘要： In this paper, we consider the singularity category D-sg(mod A) and the Z-graded singularity category D-sg(mod(Z) A) for a Gorenstein monomial algebra A. Firstly, for a positively graded 1-Gorenstein algebra, we prove that its Z-graded singularity category admits silting objects. Secondly, for A = KQ/I being a Gorenstein monomial algebra, we prove that D-sg(mod(Z) A) has tilting objects. As a consequence, D-sg(mod(Z) A) is triangulated equivalent to the derived category of a hereditary algebra H which is of finite representation type. Finally, we give a characterization of 1-Gorenstein monomial algebras, and describe their singularity categories clearly by using the triangulated orbit categories of type A. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Intrahepatic cholangiocarcinoma   Tumor size   SEER   T category  

摘要： Background The association between tumor size and survival in patients with intrahepatic cholangiocarcinoma (ICC) after hepatectomy is controversial, and the T category in the American Joint Committee on Cancer (AJCC) stage for ICC is a topic of debate. Methods Data from 611 T1-2N0M0 ICC patients classified by the AJCC 8th edition who underwent hepatectomy were extracted from the Surveillance, Epidemiology, and End Results (SEER) database during 1988-2015. Cancer-specific survival was evaluated using Kaplan-Meier analysis. The optimal cutoff value of solitary tumor size was used an adjusted p value approach to discriminating patient survival. Results In the AJCC 8th staging system, using a 5-cm cut-off value of tumor size for solitary ICC without vascular invasion (S/VI-) was not associated with survival in T1 category (p = 0.201), and multifocal ICC with vascular invasion had a worse survival than solitary ICC with vascular invasion (S/VI+) in T2 category (p = 0.014). Tumor size was a prognostic factor for both S/VI- and S/VI+, the optimal cutoff value of tumor size was obtained 8 cm for S/VI- and 3 cm for S/VI+. S/VI- <= 8 cm had a similar survival to S/VI+ <= 3 cm (p = 0.126), S/VI- > 8 cm had a similar survival to S/VI+ > 3 cm (p = 0.655), and multifocal ICC had a similar survival with S/VI- > 8 cm (p = 0.159) and S/VI+ > 3 cm (p = 0.196). When the cohort was divided into two groups-new T1 (S/VI- <= 8 cm and S/VI+ <= 3 cm) and new T2 (S/VI- > 8 cm, S/VI+ > 3 cm and multifocal ICC)-significant survival difference was observed (p < 0.0001). Conclusions The discriminatory power of the AJCC 8th edition for solitary ICC could be further enhanced by subdividing tumors according to size and vascular invasion (8 cm for S/VI- and 3 cm for S/VI+).

关键词： Lung cancer   Nodule   Screening   Radiology   Lung-RADS  

摘要： Purpose: To test the performance of the American College of Chest Physicians (ACCP) and British Thoracic Society (BTS) algorithms to stratify high-risk nodules identified at lung cancer screening. Method and Materials: Patients with Lung-RADS category 4 nodules identified on lung cancer screening computed tomography (CT) between March 2014 and August 2018 were identified, and a subset of 150 were randomly selected. Nodule characteristics and, if available, fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET)-CT scan were recorded. Radiologists blinded to final diagnosis and downstream testing performed five-point visual assessment score for probability of nodule malignancy;their accuracies are averaged below. Probabilities of malignancy according to Brock and Herder models were calculated. ACCP and BTS algorithms were applied to the nodules. Results: Final diagnosis of malignancy was made in 65/150 (43%) of patients. The sensitivity, specificity and accuracy for nodule malignancy were: radiologist visual score (92%, 85%, 88%);BTS (76%, 91%, 85%);ACCP (63%, 89%, 78%);and Brock calculator (77%, 71%, 73%). The sensitivity, specificity, and accuracy for nodule malignancy in patients with FDG PET-CT scan (n = 78) were: FDG uptake (91%, 64%, 83%);Herder probability (91%, 68%, 83%);radiologist visual score (93%, 69%, 86%);BTS (84%, 64%, 78%);Brock probability (82%, 50%, 72%);and ACCP (68%, 59%, 65%). Conclusion: Thoracic radiologist visual analysis yielded the greatest accuracy for nodule triage in the entire cohort. BTS performed better than ACCP guidelines and both performed better than the Brock model alone.

关键词： Drone   Machine learning   Beach pollution   Remote sensing   Coastal monitoring  

摘要： The use of Unmanned Aerial Systems (UAS, aka drones) images for mapping macro-litter in the environment have been exponentially increasing in the recent years. In this work, we developed a multi-class Neural Network (NN) to automatically identify stranded plastic litter categories on an UAS-derived orthophoto. The best results were assessed for items that did not have substantial intra-class colour variability, such as octopus pots and fishing ropes (F-score = 61%, on average). Instead, performance was poor (37%) for plastic bottles and fragments, due to their changing intra-class colours. On average, the performance improved 24% when the binary detection (litter/non-litter, F-Score = 73%) was considered, however this approach did not discriminate the litter categories. This work gives a new perspective for the automated litter detection on drone images, suggesting that colourbased approach can be used to improve the categorization of stranded litter on UAS orthophoto.

关键词： 工程管理   工程管理范畴   重要性  

摘要： 在社会经及不断发展以及人口基数不断增加的背景下,建筑行业也获得了相对较好的发展机遇。结合实际情况来看,在建筑工程各行中,工程管理工作的开展尤为重要,而在现代化以及西方先进工程管理理念的影响下,传统管理模式的弊端愈发明显。基于此,本文结合实际情况深入分析工程管理的范畴以及其开展的重要性,望能够对相关工作的开展起到一定的帮助。