bluuebunny/crossref_metadata_2025 huggingface dataset:
High-Order Observer-Based Sliding Mode Control for the Isolated Microgrid with Cyber Attacks and Physical Uncertainties
Authors: Wang Hao , Jiang He , Zhao Yan , Guan Huanxin , Hu Bo , Wang Shunjiang
Published: December 2020

System security is essential for the operation of the island microgrid. However, the system security is generally threatened due to the presence of physical uncertainties and cyber attacks. In this article, a novel sliding mode load control strategy is proposed for the microgrid to mitigate cyber attacks and physical uncertainties. Firstly, a high-order disturbance observer (HODO) is designed to estimate the unmeasurable factors in the microgrid. Secondly, a HODO-based sliding mode control (SMC) strategy is proposed where the estimated value observed by the HODO is applied to the sliding mode surface and control law. It can better guarantee the security of the isolated microgrid. Then, the stability of the HODO-based SMC is demonstrated by Lyapunov stability theory. Finally, simulation results show that the proposed control strategy has excellent control performance.
Study on the Failure Characteristics of Coal Wall Spalling in Thick Coal Seam with Gangue
Authors: Li Guosheng , Li Zhenhua , Du Feng , Cao Zhengzheng
Published: December 2020

Coal wall spalling is one of the main factors restricting the safe and efficient mining of thick coal seam, and the gangue has an important impact on the coal wall spalling. To obtain the failure characteristics of coal wall spalling in thick coal seam containing gangue, numerical calculation and theoretical research were used to analyze the morphological differences of coal wall spalling with different gangue positions. Besides, the damage depth, width, and stress environment of coal wall panel caused by the position of gangue were mainly studied, and the failure mechanics model of coal seam containing gangue was established by using the stability theory of pressure bar. The results show that, compared with coal wall spalling in coal seam without gangue, coal seam with the lower and middle gangue has a significant weakening effect on the wall spalling, and coal seam with the upper gangue has little effect on the wall spalling. In the case of coal seam with gangue, the upper gangue has the highest risk area of coal wall spalling with the maximum depth and width of 2.0 m and 2.3 m. For coal seam with the upper gangue, the dangerous areas of coal wall spalling are mainly distributed in the vicinity of the gangue; for coal seam without the gangue, they are mainly distributed in the middle of the coal seam. The gangue cannot change the law of the external stress distribution of the coal seam, but it has an obvious impact on the internal stress distribution of the coal seam. With the different positions of the gangue, the stress distribution in the coal seam has a great difference, and the maximum difference is 1.8 MPa. This shows that the stress environment of the coal seam containing gangue has the following typical characteristics: “the external stress is controlled by the overburden fracture, and the internal stress environment is controlled by the gangue.” Through the mechanical analysis of the coal seam containing gangue, it is further verified that the coal seam containing gangue is more prone to spalling at the position of gangue.
Bupleurum chinense Polysaccharide Improves LPS‐Induced Senescence of RAW264.7 Cells by Regulating the NF‐κB Signaling Pathway
Authors: Xu Mengran , Sun Shengyang , Ge Junhong , Shen Ye , Li Tan , Sun Xin
Published: December 2020

Macrophages are important inflammatory cells that play a vital role in inflamm‐aging. Bupleurum chinense polysaccharide (BCP), an effective component of the Bupleurum chinense herb, exerts multiple beneficial pharmacological effects, such as improving immunity and antioxidant activity. However, the effects of BCP on macrophage‐aging and inflamm‐aging are yet to be established. In this study, we examined the effects of BCP on proliferation, inflammatory cytokines, β‐galactosidase (SA‐β‐gal), senescence‐associated heterochromatin foci (SAHF), reactive oxygen species (ROS), mitochondrial membrane potential, p53, p16, and p65/NF‐κB signaling proteins in lipopolysaccharide (LPS)‐stimulated RAW264.7 cells. BCP significantly inhibited production of interleukin‐1α (IL‐1α), interleukin‐6 (IL‐6), and tumor necrosis factor‐α (TNF‐α), reduced the expression of SA‐β‐gal and formation of SAHF, as well as ROS level, and stabilized the mitochondrial membrane potential in RAW264.7 cells stimulated with LPS. Furthermore, BCP inhibited the expression of aging‐related genes, p53 and p16, suppressed phosphorylation of p65 protein, and enhanced the expression of I‐κBα protein through the NF‐κB signaling pathway in LPS‐stimulated RAW264.7 cells. Accordingly, we conclude that BCP effectively suppresses inflamm‐aging by reducing inflammatory cytokine levels and oxidative stress production following activation of the NF‐κB signaling pathway in RAW264.7 cells stimulated with LPS. Our collective findings support the utility of BCP as a novel pharmaceutical agent with potential anti‐inflamm‐aging effects.
Prevalence of Gastrointestinal Parasites in the Frugivorous and the Insectivorous Bats in Southcentral Nepal
Authors: Adhikari Roshan Babu , Maharjan Mahendra , Ghimire Tirth Raj
Published: December 2020

Bats are the only active flying placental mammals and are traditionally classified into mega- and microbats, which are, respectively, herbivorous and insectivorous in feeding habit. Though deforestation, habitat destruction, natural calamities, illegal hunting, and climate changes are the challenging threats for bats, the role of existing gastrointestinal (GI) parasites have not been evaluated yet in Nepal. Thus, the current study aims to determine the prevalence of GI parasites in bats from the Shaktikhor area at the Chitwan district of Southcentral Nepal. From July 2018 to February 2019, a total of 60 fecal samples of bats (30 from frugivorous bats and 30 from the insectivorous bats) were collected. These samples were preserved at 2.5% potassium dichromate solution. The fecal examination was carried out by the direct wet mount, concentrations, acid-fast staining, and sporulation techniques. Overall results showed the prevalence rate of 80% GI parasites. The parasites detected in the insectivorous bats were Ascarid spp., Capillarid sp., Cryptosporidium sp., Eimeria spp., Entamoeba sp., Giardia sp., Hymenolepis spp., Isospora sp., Oxyurid sp., Strongyle, and Strongyloides sp. In contrast, Eimeria sp., Entamoeba sp., and Hymenolepis sp. were detected in the frugivorous bats. Based on a wide diversity of parasite richness and parasitic concurrency measured by the prevalence rates, we suggest that GI parasitism might be a threatening factor in the insectivorous bats in the current study area.
Two-Round Password-Based Authenticated Key Exchange from Lattices
Authors: Yin Anqi , Guo Yuanbo , Song Yuanming , Qu Tongzhou , Fang Chen
Published: December 2020

Password-based authenticated key exchange (PAKE) allows participants sharing low-entropy passwords to agree on cryptographically strong session keys over insecure networks. In this paper, we present two PAKE protocols from lattices in the two-party and three-party settings, respectively, which can resist quantum attacks and achieve mutual authentication. The protocols in this paper achieve two rounds of communication by carefully utilizing the splittable properties of the underlying primitive, a CCA (Chosen-Ciphertext Attack)-secure public key encryption (PKE) scheme with associated nonadaptive approximate smooth projection hash (NA-ASPH) system. Compared with other related protocols, the proposed two-round PAKE protocols have relatively less communication and computation overhead. In particular, the two-round 3PAKE is more practical in large-scale communication systems.
Safety of Ertugliflozin in Patients with Type 2 Diabetes Mellitus Inadequately Controlled with Conventional Therapy at Different Periods: A Meta-Analysis of Randomized Controlled Trials
Authors: Huang Jing , Xiong Shuyuan , Ding Shenglan , Cheng Qingfeng , Liu Zhiping
Published: December 2020

Aims. To assess the safety of ertugliflozin in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with conventional therapy at different periods. Methods. We searched PubMed, Embase, and The Cochrane Library from inception to September 23, 2020. A total of six studies involving 4120 patients were included. Results. Compared with the control group, 15 mg and 5 mg of ertugliflozin were associated with higher risks of genital mycotic infections (GMIs) at 26 weeks (

p
<
0.0001

and

p
<
0.0001

, respectively), 52 weeks (

p
<
0.00001

and

p
<
0.0001

, respectively), and 104 weeks (

p
<
0.00001

and

p
<
0.0001

, respectively). Moreover, females had a higher risk of GMIs than males in the 15 mg group at 26 weeks (

p
=
0.0008

), 52 weeks (

p
<
0.0001

), and 104 weeks (

p
=
0.02

). At 104 weeks, 15 mg and 5 mg of ertugliflozin showed beneficial effects on symptomatic hypoglycemia (

p
<
0.00001

and

p
=
0.004

, respectively) compared with the effects observed in the control group. Compared with the control group, 15 mg and 5 mg of ertugliflozin were associated with higher risks of drug-related adverse events at 26 weeks (

p
=
0.002

and

p
=
0.002

, respectively); 15 mg of ertugliflozin was associated with a higher risk of discontinuation related to adverse events at 104 weeks (

p
=
0.03

). No significant differences were found in the remaining safety outcomes. Conclusion. This meta-analysis of randomized controlled trials indicates that ertugliflozin is tolerated by T2DM, but the risk of GMIs is noteworthy, especially among females in the high-dose group.
Coordination Effects and Optimal Policy Choices of Macroprudential Policy and Monetary Policy
Authors: Pan Haifeng , Zhang Dingsheng
Published: December 2020

Considering three monetary policy rules, together with two endogenous macroprudential policies that are credit constraints (loan to value, LTV) for households and counter-cyclical capital (capital requirement ratio, CRR) for bankers, this paper establishes a dynamic stochastic general equilibrium (DSGE) model. Based on the welfare analysis of different combinations of macroprudential rules and monetary policy rules, this paper identifies the optimal policy combinations and analyzes the coordination effects between macroprudential policies and monetary policies. The results show that no matter what kind of monetary policy rules is implemented, the introduction of macroprudential rules has improved the level of total social welfare. In the optimal “two pillars” framework of monetary policies and macroprudential rules, the main objective of monetary policy is to stabilize price inflation, and the macroprudential policy to be implemented is the CRR macroprudential policy. This combination can effectively promote the stability of the real estate market, financial market, and macroeconomy, while maximizing the improvement of total social welfare.
Underestimation of Cognitive Impairment in Older Inpatients by the Abbreviated Mental Test Score versus the Montreal Cognitive Assessment: Cross-Sectional Observational Study
Authors: Emery Alexander , Wells James , Klaus Stephen P. , Mather Melissa , Pessoa Ana , Pendlebury Sarah T.
Published: December 2020

Background/Aims: Cognitive impairment is prevalent in older inpatients but may be unrecognized. Screening to identify cognitive deficits is therefore important to optimize care. The 10-point Abbreviated Mental Test Score (AMTS) is widely used in acute hospital settings but its reliability for mild versus more severe cognitive impairment is unknown. We therefore studied the AMTS versus the 30-point Montreal Cognitive Assessment (MoCA) in older (≥75 years) inpatients. Methods: The AMTS and MoCA were administered to consecutive hospitalized patients at ≥72 h after admission in a prospective observational study. MoCA testing time was recorded. Reliability of the AMTS for the reference standard defined as mild (MoCA <26) or moderate/severe (MoCA <18) cognitive impairment was assessed using the area under the receiver-operating curve (AUC). Sensitivity, specificity, positive and negative predictive values of low AMTS (<8) for cognitive impairment were determined. Results: Among 205 patients (mean/SD age = 84.9/6.3 years, 96 (46.8%) male, 74 (36.1%) dementia/delirium), mean/SD AMTS was 7.2/2.3, and mean/SD MoCA was 16.1/6.2 with mean/SD testing time = 17.9/7.2 min. 96/205 (46.8%) had low AMTS whereas 174/185 (94%) had low MoCA: 74/185 (40.0%) had mild and 100 ( 54.0%) had moderate/severe impairment. Moderate/severe cognitive impairment was more prevalent in the low versus the normal AMTS group: 74/83 (90%) versus 25/102 (25%, p < 0.0001). AUC of the AMTS for mild and moderate/severe impairment were 0.86 (95% CI = 0.80–0.93) and 0.88 (0.82–0.93), respectively. Specificity of AMTS <8 for both mild and moderate/severe cognitive impairment was high (100%, 71.5–100, and 92.7%, 84.8–97.3) but sensitivity was lower (44.8%, 37.0–52.8, and 72.8%, 62.6–81.6, respectively). The negative predictive value of AMTS <8 was therefore low for mild impairment (10.9%, 5.6–18.7) but much higher for moderate/severe impairment (75.2%, 65.7–83.3). All MoCA subtests discriminated between low and normal AMTS groups (all p < 0.0001, except p = 0.002 for repetition) but deficits in delayed recall, verbal fluency and visuo-executive function were prevalent even in the normal AMTS group. Conclusion: The AMTS is highly specific but relatively insensitive for cognitive impairment: a quarter of those with normal AMTS had moderate/severe impairment on the MoCA with widespread deficits. The AMTS cannot therefore be used as a “rule-out” test, and more detailed cognitive assessment will be required in selected patients.
Surgery for Ampullary Cancer in a Patient with Pancreatic Lipomatosis Caused by Cystic Fibrosis
Authors: Vuurberg Nienke E. , Bakker Ilsalien , van den Boom Anne Loes , de Haas Robbert J. , Duiker Evelien W. , van den Heuvel Marius C. , Klaase Joost M.
Published: December 2020

A patient with cystic fibrosis (CF) with pancreatic insufficiency presented with jaundice due to an ampullary tumour. CF is known for a higher incidence of gastrointestinal malignancies. The patient suffered from pancreatic insufficiency. At computed tomography (CT), pancreatic lipomatosis with absence of the pancreatic duct was seen. This is uncommon, also in patients with CF. During surgery, a total pancreatectomy was performed, because there was no possibility to construct a duct to mucosa anastomosis due to the absence of the pancreatic duct and more importantly the pancreas was already afunctional. The presence of lipomatosis increases the risk of leakage at the pancreaticojejunal anastomosis. Therefore, it is important to take this phenomenon, in this case already visible on the preoperative CT scan, into account during the workup for surgery.
The Association between Antidiabetic Agents and Leukocyte Telomere Length in the Novel Classification of Type 2 Diabetes Mellitus
Authors: Huang Jiaojiao , Peng Xuemin , Dong Kun , Tao Jing , Yang Yan
Published: December 2020

Aims: This study aimed to explore the new role of telomere length (TL) in the novel classification of type 2 diabetes mellitus (T2DM) patients driven by cluster analysis. Materials and Methods: A total of 541 T2DM patients were divided into 4 subgroups by k-means analysis: mild obesity-related diabetes (MOD), severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD), and mild age-related diabetes (MARD). After patients with insufficient data were excluded, further analysis was conducted on 246 T2DM patients. The TL was detected using telomere restriction fragment, and the related diabetic indexes were also measured by clinical standard procedures. Results: The MARD group had significantly shorter TLs than the MOD and SIDD groups. Then, we subdivided all T2DM patients into the MARD and NONMARD groups, which included the MOD, SIDD, and SIRD groups. The TLs of the MARD group, associated with age, were discovered to be significantly shorter than those of the NONMARD group (p = 0.0012), and this difference in TL disappeared after metformin (p = 0.880) and acarbose treatment (p = 0.058). The linear analysis showed that metformin can more obviously reduce telomere shortening in the MARD group (r = 0.030, 95% CI 0.010–0.051, p = 0.004), and acarbose can more apparently promote telomere attrition in the SIRD group (r = –0.069, 95% CI –0.100 to –0.039, p< 0.001) compared with other T2DM patients after adjusting for age and gender. Conclusions: The MARD group was found to have shorter TLs and benefit more from the antiaging effect of metformin than other T2DM. Shorter TLs were observed in the SIRD group after acarbose use.
A Three-Arm Randomized Clinical Trial Comparing the Efficacy of a Mindfulness-Based Intervention with an Active Comparison Group and Fluoxetine Treatment for Adults with Generalized Anxiety Disorder
Authors: Costa Marianna de Abreu , Gonçalves Francine Guimarães , Tatton-Ramos Tiago , Fonseca Natasha Kim de Oliveira da , Schwinn Julia Karl , Alves Sofia Giusti , Salum Giovanni Abrahão , Manfro Gisele Gus
Published: December 2020

Introduction: Mindfulness-based interventions have been studied as an alternative treatment for anxiety disorders, but there are only a few studies comparing these with established treatments. Objective: To evaluate the efficacy of a Body in Mind Training (BMT) program for adults with generalized anxiety disorder (GAD), an active comparison protocol called Quality of Life and Psychoeducation (QoL), and treatment with fluoxetine (FLX). Methods: This study comprises a 3-arm parallel-group, randomized clinical trial (ClinicalTrials.gov ID: NCT03072264). Adults with a primary diagnosis of GAD and no current treatment were recruited from the community and randomized in a ratio 1:1:1. The primary outcomes were assessed by means of the Hamilton Anxiety Rating Scale (HAM-A) and the Penn State Worry Questionnaire (PSWQ) at week 8. Data were analyzed using a superiority analysis (BMT vs. QoL) and a noninferiority analysis (BMT vs. FLX). Results: A total of 249 participants were included and 223 were analyzed (76 BMT, 79 FLX, and 68 QoL). All groups improved after intervention. However, BMT was not superior to QoL at week 8 (mean difference = –1.36; p = 0.47), nor was it noninferior to FLX as assessed with theHAM-A (mean difference = 3.5; 95% CI –0.06 to 7.06; noninferiority margin = –2.43; p = 0.054). QoL (mean difference = 3.54; p = 0.04) and FLX (mean difference = –7.72; 95% CI –10.89 to –4.56; noninferiority margin = –2.09; p < 0.001) were superior to BMT in reducing PSWQ score. Conclusion: Our data suggest that BMT, in its current format, cannot be considered an effective mindfulness protocol to improve GAD.
Clinicopathological and Endoscopic Features of Raspberry-Shaped Gastric Cancer in Helicobacter pylori-Uninfected Patients
Authors: Yatagai Noboru , Ueyama Hiroya , Ikemura Muneo , Uchida Ryota , Utsunomiya Hisanori , Abe Daiki , Oki Shotaro , Suzuki Nobuyuki , Ikeda Atsushi , Akazawa Yoichi , Komori Hiroyuki , Takeda Tsutomu , Matsumoto Kohei , Ueda Kumiko , Matsumoto Kenshi , Asaoka Daisuke , Hojo Mariko , Tsuyama Sho , Hayashi Takuo , Yao Takashi , Nagahara Akihito
Published: December 2020

Background: Gastric adenocarcinoma of foveolar type (GA-FV) is a raspberry-shaped gastric cancer (RSGC) and garners much attention as H. pylori (Hp)-uninfected gastric cancer. However, the classification and clinicopathological and endoscopic features of RSGCs in Hp-uninfected patients are poorly defined. We designed a new histopathological classification of RSGC and compared them via endoscopic and clinicopathological characteristics. Summary: From 996 patients with early gastric cancers resected by endoscopy in our hospital, we studied 24 RSGC lesions from 21 (2.4%) Hp-uninfected patients. RSGCs were classified into 3 histological types as follows: GA-FV (n = 19), gastric adenocarcinoma of fundic gland type (GA-FG, n = 2), and gastric adenocarcinoma of fundic gland mucosa type (GA-FGM, n = 3). Most of the lesions were found at the greater curvature of the upper or middle third of the stomach. GA-FV lesions were homogeneously reddish and frequently accompanied with a whitish area around the tumor and an irregular microvascular (MV) pattern; these features were confirmed histopathologically by the presence of homogeneous neoplastic foveolar epithelium with foveolar hyperplasia around the tumors. GA-FG lesions might be heterogeneously reddish with a submucosal tumor shape and regular MV pattern; these were confirmed by the presence of covered or mixed nonneoplastic epithelium on deeper regions of tumors. GA-FGM lesions might be homogeneously reddish and occasionally had a submucosal tumor shape and irregular MV pattern; these were confirmed by the presence of homogeneous neoplastic foveolar epithelium on deeper regions of the tumors. Key Messages: RSGCs in Hp-uninfected patients are classified into 3 histopathological types. For accurate diagnosis of RSGCs, it may be necessary to fully understand endoscopic features of these lesions based on these histological characteristics and to take a precise biopsy.
Exacerbation Rate in Generalized Myasthenia Gravis and Its Predictors
Authors: Abuzinadah Ahmad R. , Alanazy Mohammed H. , Butt Nadeem S. , Barohn Richard J. , Dimachkie Mazen M.
Published: December 2020

Objective: The aim of the study was to estimate the exacerbation incidence rate (IR) in acetylcholine receptor antibody (AChR)-positive generalized myasthenia gravis (MG) and its predictors. Methods: The primary outcome in this retrospective study was to estimate moderate-to-severe (M-S) exacerbations IR in the early course of generalized MG. The secondary outcome was to explore the predictors of MG exacerbations. Results: Between 1999 and 2015, we identified 78 AChR-positive generalized MG patients and 37 M-S exacerbations over the first 6 years following the onset of generalized MG symptoms. The M-S exacerbation IR was 12.2 per 100 person years (95% confidence interval [CI] 8.8–16.8). Any exacerbation (including mild) IR was 24.4 per 100 person years (95% CI 19.4–30.7). After controlling for confounding factors, MG exacerbation IR predictors included gender, disease severity at onset, and prednisone dose reduction with risk ratio of 0.34 (male gender), 2.67, and 20.8, respectively (all p values <0.05). M-S exacerbation occurred in 25 cases (32.1%), while any exacerbation (mild or M-S) was detected in 45 cases (57.7%). Conclusion: More than half of newly diagnosed AChR + MG cases experience an exacerbation in the first 6 years. Gender, disease severity at onset and prednisone dose reduction are predictors that could inform clinical practice and future research.
Shared Decision-Making in Oncology: Preferences in Older versus Younger Patients of an Oncology Clinic – A Conjoint Analysis
Authors: Gaster Corinna , Hofheinz Ralf-Dieter , Burkhardt Heinrich
Published: December 2020

Background: Data concerning older patients’ preferences with regard to physician-patient interaction and the concept of shared decision-making (SDM) in oncology are still sparse although significantly influencing treatment planning. Methods: Patients were recruited as a convenience sample from an outpatient oncology department. To test for patients’ attitudes toward participating in clinical decisions, the PEF-FB-9 questionnaire (the German version of SDM-Q9) and the autonomy preference index (API) instrument were applied. A conjoint analysis was performed by a full set of vignettes exposing three different clinical attributes: clinical experience in oncology of the responsible physician, type of hospital, and type of physician-patient interaction in decision-making. Two independent cohorts were retrieved: patients aged <65 years and patients aged >70 years. Results: A total of 71 patients were included. Younger subjects rated higher (44 vs. 10, p < 0.001) on the API scale. In both cohorts, physician-patient interaction received the highest preference values compared with type of hospital and physician experience. Analysis for age differences on preference values showed significantly higher values among the older patients concerning physician-patient interaction and lower values concerning type of hospital. Further analysis of the preferred type of physician-patient interaction revealed the highest preference in both cohorts for SDM. Conclusions: The high significance of physician-patient interaction could be proved. As a SDM approach is preferred in older and younger patients, an age-related different approach does not seem appropriate.
COVID-19 in ESRD and Acute Kidney Injury
Authors: Kooman Jeroen P. , van der Sande Frank M.
Published: December 2020

The COVID-19 pandemic has greatly affected nephrology. Firstly, dialysis patients appear to be at increased risk for infection due to viral transmission next to an enhanced risk for mortality as compared to the general population, even in the face of an often apparently mild clinical presentation. Derangements in the innate and adaptive immune systems may be responsible for a reduced antiviral response, whereas chronic activation of the innate immune system and endothelial dysfunction provide a background for a more severe course. The presence of severe comorbidity, older age, and a reduction of organ reserve may lead to a rapid deterioration of the clinical situation of the patients in case of severe infection. Secondly, patients with COVID-19 are at increased risk of acute kidney injury (AKI), which is related to the severity of the clinical disease. The presence of AKI, and especially the need for renal replacement therapy (RRT), is associated with an increased risk of mortality. AKI in COVID-19 has a multifactorial origin, in which direct viral invasion of kidney cells, activation of the renin-angiotensin aldosterone system, a hyperinflammatory response, hypercoagulability, and nonspecific factors such as hypotension and hypoxemia may be involved. Apart from logistic challenges and the need for strict hygiene within units, treatment of patients with ESRD and COVID-19 is not different from that of the general population. Extracorporeal treatment of patients with AKI with RRT can be complicated by frequent filter clotting due to the hypercoagulable state, for which regional citrate coagulation provides a reasonable solution. Also, acute peritoneal dialysis may be a reasonable option in these patients. Whether adjuncts to extracorporeal therapies, such as hemoadsorption, provide additional benefits in the case of severely ill COVID-19 patients needs to be addressed in controlled studies.
Geometria: soluções detalhadas para 20 problemas de Olimpíadas Internacionais de Matemática
Authors:   Universidade de São Paulo. Faculdade de Zootecnia e Engenharia de Alimentos, Linares Juan López
Published: December 2020

Este é o terceiro livro eletrônico do autor dedicado à resolução de problemas de olimpíadas internacionais de Matemática. Nesta oportunidade são apresentadas vinte questões de Geometria plana. O texto conta com cinquenta figuras que facilitam acompanhar as soluções. Muitos exercícios têm como complemento gráficos interativos no site do Geogebra e vídeos no YouTube, em que são discutidos assuntos como: trigonometria, quadriláteros notáveis e cíclicos, ângulos na circunferência, potência de um ponto e eixo radical, congruência e semelhança de triângulos e cálculo de área, acrescentando que cada questão utiliza conhecimentos ligados a mais de um ramo do conhecimento. Espera-se que o material exposto na obra possa ser lido e estudado por alunos de língua portuguesa (e talvez espanhola) que se preparam para as fases finais das olimpíadas nacionais ou internacionais e vestibulares, e que a presente abordagem sirva de apoio aos professores do Ensino Médio que se aventuram em tópicos mais avançados.
En las fauces de la muerte y la locura: reflexiones en torno a la prosa de Georg Heym
Authors: Andrade Ricardo
Published: December 2020

El presente artículo propone estudiar a una figura destacada del movimiento expresionista alemán poco conocido en lengua española: Georg Heym. Notorio especialmente por su poesía y la fuerte influencia que ejerció en el desarrollo de la lírica en la Alemania del siglo XX, el estudio busca explorar la faceta menos conocida del autor: sus Novellen. A través de este género, el autor radicaliza sus exploraciones estéticas, al mismo tiempo que expone las formaciones ideológicas de la burguesía del Imperio Alemán. En este sentido, el presente trabajo también ofrece una lectura política y las consecuencias de la creación artística expresionista en la configuración espiritual del nacionalsocialismo y la identidad alemana. Para indagar a profundidad dichas relaciones entre filosofía, política y literatura en la Alemania guillermina, se toma en consideración una selección de las Novellen más emblemáticas del autor. Teniendo en cuenta esto, el artículo presenta una lectura renovada de un autor fundamental en la historia de la literatura alemana.
Os microdramas de Wolfgang Bauer: o riso como liberação e como provocação
Authors: Bohunovsky Ruth
Published: December 2020

À primeira vista, os microdramas de Wolfgang Bauer, escritos nos anos 1960, parecem ser nada mais do que pequenas brincadeiras engraçadas com o gênero dramático e suas convenções. Partindo da constatação que eles tiveram um considerável efeito provocativo, e até político, no contexto conservador da Áustria daquela década, propõe-se uma reflexão sobre a relação entre a sua comicidade e o seu potencial incitador. Com base em estudos sobre características e efeitos da obra de Wolfgang Bauer (Antonic [2018; 2019]; Melzer [1981], Waggershauser [2016]) e nas teorizações sobre a experiência do cômico de Peter L. Berger (1998) e Uwe Wirth (1999), este artigo sugere que os microdramas de Bauer não são apenas um exemplo de metateatro bastante inovador. Eles permitem surgir um riso “redentor”, libertador, que também pode ser sentido como uma provocação política, especialmente em contextos sociais marcados por discursos essencialistas e/ou fundamentalistas.
O texto e o pacto: estratégias discursivas em Casa-grande & senzala para pactuar a democracia racial
Authors: Melo Alfredo Cesar
Published: December 2020

Baseado na complexa e multidimensional definição de democracia racial estabelecida por Antonio Sérgio Alfredo Guimarães (mito, ideal e pacto), examinamos como Casa-grande & senzala participa da construção do pacto racial-democrático ensaiado no final dos anos 1930 no Brasil. Para isso analisamos como Gilberto Freyre estabelece discurso performativo sobre a democracia racial, em que supostamente se constatariam as interações não racistas dos brasileiros, ao mesmo tempo que também articula um discurso da democracia racial como pedagogia, em que ele desmente os estigmas raciais relacionados à presença do negro no Brasil, e busca celebrar as contribuições materiais e imateriais dos negros à cultura brasileira. Pretendemos mostrar como as ações linguísticas geradas no texto formam um campo de força discursivo essencial para a elaboração da democracia racial como pacto.
Abstract P113: Increased Incidence of Atrial Fibrillation During Periods of High Influenza Activity
Authors: Safavi-Naeini Payam , Razavi Mehdi , Rasekh Abdi , Madjid Mohammad
Published: December 2020

Introduction:
Influenza is an important inflammatory illness which results in 3 to 5 million cases of severe illness, and 290,000 to 650,000 deaths per year, worldwide. Influenza’s role in triggering acute coronary syndromes is well established, but influenza’s impact on cardiac arrhythmias has yet to be investigated.

Hypothesis:
We investigated the effect of influenza on triggering atrial fibrillation (AFib) episodes.

Methods:
This retrospective observational study included de-identified data from patients who had a Zio patch (iRhythm Technologies, San Francisco), a wearable continuous cardiac monitoring device. Data were available from October 2012 to September 2017. The “influenza activity” was defined as the percentage of positive respiratory specimens that tested for influenza virus during each influenza season reported by the Centers for Disease Control and Prevention (CDC). We included all cases with AFib burden <=90% from the weeks with the highest and lowest influenza activity up to two consecutive weeks after them. An independent-samples t-test was used to compare the burden of AFib in weeks with the highest and lowest influenza activity.

Results:
We reviewed the records of 825,869 patients (mean age= 61.1 ± 15.3 years; 48.8% male) who had a Zio patch from October 2012 to September 2017. Of these patients, 47,106 met the pre-defined inclusion criteria for our study. There was a significant difference in the AFib burden in high influenza activity (Mean=1.19, SD=0.69) and low influenza activity (Mean=1.03, SD=0.63) conditions; t (47104) = -2.6, p =0.009. The incidence of AFib was 15% higher in high influenzas activity weeks (OR=1.15, 95%CI, 1.03-1.19, p=0.009). The higher burden of AFib in high influenza activity weeks was significant for each influenza season and a similar trend was observed consistently in each individual influenza season.

Conclusions:
High seasonal influenza activity is associated with increased odds of AFib. Prospective studies are needed to determine the clinical implications of this finding.
Abstract P218: Dietary Prescription in the Coronary Care Unit, Missed Opportunity to Improve Care?
Authors: Al-Sadawi Mohammed , Ihsan Muhammad , Kiladejo Adekunle , Mitchell Judith E
Published: December 2020

Introduction:
A notable portion of the excess burden of cardiovascular disease [CVD] risk factors in African Americans [AA] is believed secondary to the diet.

Hypothesis:
Dietary assessment and prescribed diets are inadequate in patients admitted to the coronary care unit [CCU].

Results:
Cohort: 267 consecutively patients, AA 83%, male 55%, mean age 65 yrs, were assessed for cardiovascular [CV] risk factors, clinical status and appropriateness of prescribed diets. Patients were at increased CV risk as evidenced by 65% older than 60 yrs, Body Mass Index (BMI) >30 in 40% with women almost twice as likely to be obese [p<0.006], history of smoking 55%, hypertension 90%, diabetes 54%, and mean ejection fraction 43%. Established CAD acknowledged in 60%. Breakdown of diet orders: normal diet 11%, diabetic diet 38% and a form of low sodium, low cholesterol diet in 51%. CCU length of stay: 2.5 days with no significant difference by sex, diabetic or obesity status. Dietary assessment documentation was missing in 40% of the CCU admissions. A significant percentage of the patients missing this documentation were women [45%], diabetics [47%], obese--BMI>30 [42%] and older--age >60 [68%]. Incongruence is seen between the disease burden and the appropriate dietary order. For example, 54% of patients had DM. However, only 38% were given a diabetic diet. A form of low Na diet was provided to 51% of the patients yet 90% of them were hypertensive or had a history of hypertension. The statistic, dietary assessment not recorded in 40% of the patients, may have been affected by the relatively short CCU stay. One limitation of our study is that we did not examine if this decreased dietary assessment rate was affected by week-day vs. weekend stay in the CCU or by the severity of the patient’s illness.

Conclusion:
Dietary assessment and appropriate dietary prescription matters. Recent studies show that dietary pattern is one of the largest mediating factors for differences in the incidence of CV risks, i.e. hypertension, in blacks vs. whites accounting for some of the excess risk among blacks. Not adequately addressing nutrition in a CCU setting leads to the loss of a critical teachable moment.
Abstract P306: Racial/Ethnic Differences In Self-reported Sedentary Time Are Related To Differential Risk For Prevalent Hypertension: NHANES 2011-2016
Authors: Mattingly Jennifer L , Petrov Megan E
Published: December 2020

Introduction:
Evidence suggests there are racial/ethnic differences in lifestyle behaviors that may affect cardiovascular health outcomes such as physical activity engagement, diet, and sleep duration. However, the literature on racial/ethnic differences in sedentary time (ST) and whether these differences may be related differentially to cardiovascular health is limited. The goals of this study are to investigate racial/ethnic differences in self-reported ST, and examine if the modifying effect of ST with race/ethnicity will be associated with hypertension (HTN) prevalence.

Methods:
Adults (N=15903, age ≥20 yrs) from the National Health and Nutrition Examination Survey (NHANES) 2011-2016 reported their race/ethnicity (Mexican American [MA], Other Hispanic [OH], non-Hispanic White [NHW], non-Hispanic Black [NHB], non-Hispanic Asian, Other or mixed race [OM]), ST on a typical day (median split at 6 hrs: Low vs. High ST), and history of physician diagnosed HTN (yes/no). Weighted logistic regression models were conducted to examine the association between race/ethnic groups and ST, and combined racial/ethnic-ST groups (reference group: NHW with Low ST) on HTN prevalence while controlling for age, sex, education, body mass index, smoking status, moderate-vigorous physical activity min/wk, and history of diabetes, cardiovascular (i.e., heart failure, myocardial infarction, stroke, coronary heart disease) and kidney conditions.

Results:
There was a significant association between race/ethnic groups and ST (Wald
F
[5,43]=23.4,
p
<0.001) such that compared to NHW, MA (OR=.43, 95%CI:.36,.51) OH (OR=.51, 95%CI:.42,.62), and OM (OR=.71, 95%CI:.55,.91) had lower odds for High ST. Weighted percent of the sample with HTN was 32.6%. There was a significant effect of combined race by ST groups on HTN (Wald
F
[11,37] = 9.8,
p
<0.001). Compared to NHW with Low ST, MA (OR=.70, 95%CI: .54,.90) and OH (OR=.79, 95%CI: .64,.97) with Low ST had lower odds for HTN, whereas NHB with Low ST (OR=1.58, 95%CI: 1.34,1.87) and High ST (OR=1.76, 95%CI: 1.50,2.07) had increased odds of HTN.

Conclusion:
In a large national cohort, daily ST differed by race/ethnicity, and ST modified the association between race/ethnicity and odds for HTN such that compared to more active NHW, more active Hispanic groups had decreased odds for HTN, but NHB regardless of ST had increased risk for HTN. ST may be a key modifiable risk factor in addressing race/ethnic disparities in cardiovascular health.
Abstract P342: Development of a Mixture Model With Smoothing Functions of Trajectories
Authors: Ding Ming , Fitzmaurice Garrett
Published: December 2020

In the health and social sciences, two types of mixture model have been widely used by researchers to identify heterogeneous trajectories of participants within a population: latent class growth analysis (LCGA) and the growth mixture model (GMM). Both methods parametrically model trajectories of individuals, and capture latent trajectory classes, by using an expectation-maximization (E-M) algorithm. However, parametric modeling of trajectories using polynomial functions or monotonic spline functions results in limited flexibility for modelling trajectories; as a result, group membership may not be classified accurately due to model misspecification. In this paper, we propose a mixture model (SMM) allowing for smoothing functions of trajectories using a modified E-M algorithm. In the E step, participants are reassigned to only one group for which the estimated trajectory is the most similar to the observed one; in the M step, trajectories are fitted using generalized additive mixed models (GAMM) models with smoothing functions of time. This modified E-M algorithm is straightforward to implement using the recently released “gamm4” macro in R. The SMM can incorporate time-varying covariates and be applied to longitudinal data with normal, Bernoulli, and Poisson distributions. Simulation results show favorable performance of the SMM in terms of classification of group membership. The proposed method is illustrated by its application to body mass index data of individuals followed from adolescence to young adulthood and the relationship with incidence of cardiometabolic disease.
Abstract P374: Associations Of Renin-angiotensin System Blockade Discontinuation With End-stage Kidney Disease, Major Adverse Cardiovascular Events, And Death Among People With Chronic Kidney Disease
Authors: Qiao Yao , Shin Jung-im , Chen Teresa , Inker Lesley , Coresh Josef , Alexander G Caleb , Jackson John , Chang Alex R , Grams Morgan
Published: December 2020

Introduction:
Among individuals with impaired kidney function, whether and when angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARB) should be discontinued is unclear. We investigated the associations of ACE-I/ARB discontinuation with end-stage kidney disease (ESKD), major adverse cardiovascular events (MACE), and mortality in individuals who had an eGFR decline to below 30 ml/min/1.73m
2
.

Hypothesis:
Patients with ACE-I/ARB discontinuation after an eGFR decline to below 30 ml/min/1.73m
2
are at higher risks of ESKD, MACE, and mortality.

Methods:
Using electronic health records data from the Geisinger Health System, we identified individuals who initiated ACE-I/ARB between 01/01/2004 and 02/28/2019 and had an eGFR decline to below 30 ml/min/1.73m
2
. We classified patients based on whether they discontinued ACE-I/ARB within six months following the eGFR decline. We assessed the associations of ACE-I/ARB discontinuation with ESKD, MACE, and mortality over the subsequent five years in a propensity-score matched sample.

Results:
Among the 3879 patients who met eligibility criteria, 1219 discontinued ACE-I/ARB within six months after eGFR decline to below 30 ml/min/1.73m
2
. The propensity-score matched sample contained 1190 patients under each arm. ACE-I/ARB discontinuation was associated with higher risks of mortality (hazard ratio (HR): 1.45 [95% confidence interval (CI): 1.26-1.67]) and MACE (HR: 1.37 [95% CI: 1.20-1.57]), but no significant difference in risk of ESKD (HR: 1.31 [95% CI: 0.95-1.81]). Similar patterns held when evaluating ACE-I/ARB discontinuation following a 40% or greater decline in eGFR within a year.

Conclusions:
Our findings suggest there may be benefits of continued use of ACE-I/ARB in individuals who had an eGFR decline to below 30 ml/min/1.73m
2
.
Abstract P377: Changes in Leisure-time Physical Activity and Risk of Ischemic and Hemorrhagic Stroke: The Atherosclerosis Risk in Communities Study
Authors: Cowan Logan , Tarasenko Yelena , Palta Priya , Evenson Kelly R , Lakshminarayan Kamakshi
Published: December 2020

Introduction:
Engagement in leisure-time physical activity (PA) levels recommended by the American Heart Association (AHA) is inversely associated with both ischemic and hemorrhagic stroke risk. PA levels fluctuate over the lifecourse, but the association between changes in PA from mid- to late-life and stroke risk is unknown.

Hypothesis:
Participants who maintained ideal levels of PA or increased their PA across 6 years will have lower ischemic and hemorrhagic stroke risk relative to those who had persistently poor PA.

Methods:
We included 11,658 participants of the Atherosclerosis Risk in Communities study without a history of CHD or stroke at visit 3 (1993-1995). Leisure-time PA was assessed using the modified Baecke questionnaire at visits 1 and 3 and categorized according to the AHA guidelines for PA (ideal, intermediate, or poor). All adjudicated definite and probable incident ischemic and hemorrhagic strokes between visit 3 and end of year 2013 were included. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for ischemic and hemorrhagic stroke by categories of PA at visits 1 and 3. Those with poor PA at both visits were the referent group. We adjusted for age, sex, race/center, smoking, alcohol consumption, hypertension, diabetes mellitus, LDL, HDL, triglycerides, and body mass index.

Results:
During a median of 18.7 years of follow-up, 640 incident ischemic strokes and 76 hemorrhagic strokes occurred. In adjusted analyses, participants with ideal PA at both visits had a significantly lower ischemic stroke risk (HR=0.75 (0.59, 0.96)) but not significantly lower hemorrhagic stroke risk (HR=1.27 (0.65, 2.48)). Those whose PA levels increased from poor to ideal also had lower ischemic stroke risk (HR=0.74 (0.54, 1.03)) but not hemorrhagic stroke risk (HR=0.74 (0.28, 2.02)).

Conclusion:
Increasing PA between visit 1 and visit 3 was associated with lower ischemic stroke risk. Increasing PA may be an important component of stroke prevention.
Abstract P388: Childhood Obstructive Sleep Apnea May Track Into Adolescence and Role of Weight Dynamics
Authors: He Fan , Fernandez-mendoza Julio , Bixler Edward O , Liao Duanping
Published: December 2020

Introduction:
Childhood and adolescent OSA share certain pathophysiological mechanisms. Thus, adolescent OSA may be in a continuum of childhood OSA. However, this hypothesis remains controversial.

Hypotheses:
Childhood OSA is associated with higher odds of adolescent OSA. Weight changes in this transitional period are associated with the development of OSA.

Methods:
We, firstly, conducted a meta-analyses to associate childhood and adolescent OSA based on literatures in which apnea hypopnea index (AHI) and/or OSA during both childhood and adolescence were reported. Major search engines were used to identify relevant reports. An AHI ≥ 1 was used as homologized definition of OSA at childhood and adolescence periods across all studies. From eligible studies, numbers of participants with none, remitted, incident, and persistent OSA from childhood to adolescence were abstracted. Crude relative risks (RRs) between childhood and adolescence OSA were computed by using Cochran-Mantel-Haenszel tests. A random-effects model, based on the DerSimonian and Laird method, was used to summarize the findings across studies. We, then, used data from the Penn State Child Cohort (PSCC) to analyze the association between weight changes from childhood to adolescent and incident/persistent OSA. Based on the changes of participants’ weight status (normal: BMI percentile < 85 vs. overweight/obese: BMI percentile ≥ 85) during childhood and adolescence, 4 mutually exclusive groups were formed and compared. Logistic regressions were used to associate weight gain (normal to overweight/obese) and weight loss (overweight/obese to normal) during this development stage and incident/persistent OSA. Sensitivity analyses were performed by using an AHI ≥ 5 to define OSA.

Results:
Four cohort studies, which included a total of 1473 participants, were included in the meta-analyses. The mean age during childhood and adolescence examinations were 8.5-9.8 years and 13.7-20.2 years. The pooled remission rate of childhood OSA was 52.8% (31.6%, 74.1%), while the incidence of adolescent OSA was 31.6% (15.8%, 47.4%). After weighing and summarizing RRs from individual studies, the overall RR was 1.54 (1.14, 2.08). The association was stronger [RR: 2.51 (1.65, 3.82)] in the sensitivity analysis. Based on PSCC data, we found a significant association between weight gain from childhood to adolescence and higher odds of incident OSA [OR: 2.61 (1.01, 6.81)] and a non-significant trend between weight loss and lower odds of incident OSA [OR: 0.23 (0.05, 1.06)].

Conclusion:
While a substantial proportion of childhood OSA remits in the transition to adolescence, children with OSA are more likely to have adolescent OSA than those without OSA in childhood. Weight gain and loss may contribute to the natural course of OSA during transition from childhood to adolescent, especially the onset of incident OSA.