Tohoku Mathematical Journal最新文献

{"title":"Some achieved wedge products of positive currents","authors":"Ahmad K. Al Abdulaali","doi":"10.2748/tmj.20210426","DOIUrl":"https://doi.org/10.2748/tmj.20210426","url":null,"abstract":"","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48120333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disruptions to School and Home Life Among High School Students During the COVID-19 Pandemic - Adolescent Behaviors and Experiences Survey, United States, January-June 2021.","authors":"Kathleen H Krause, Jorge V Verlenden, Leigh E Szucs, Elizabeth A Swedo, Caitlin L Merlo, Phyllis Holditch Niolon, Zanie C Leroy, Valerie M Sims, Xiaoyi Deng, Sarah Lee, Catherine N Rasberry, J Michael Underwood","doi":"10.15585/mmwr.su7103a5","DOIUrl":"10.15585/mmwr.su7103a5","url":null,"abstract":"<p><p>Youths have experienced disruptions to school and home life since the COVID-19 pandemic began in March 2020. During January-June 2021, CDC conducted the Adolescent Behaviors and Experiences Survey (ABES), an online survey of a probability-based, nationally representative sample of U.S. public- and private-school students in grades 9-12 (N = 7,705). ABES data were used to estimate the prevalence of disruptions and adverse experiences during the pandemic, including parental and personal job loss, homelessness, hunger, emotional or physical abuse by a parent or other adult at home, receipt of telemedicine, and difficulty completing schoolwork. Prevalence estimates are presented for all students and by sex, race and ethnicity, grade, sexual identity, and difficulty completing schoolwork. Since the beginning of the pandemic, more than half of students found it more difficult to complete their schoolwork (66%) and experienced emotional abuse by a parent or other adult in their home (55%). Prevalence of emotional and physical abuse by a parent or other adult in the home was highest among students who identified as gay, lesbian, or bisexual (74% emotional abuse and 20% physical abuse) and those who identified as other or questioning (76% and 13%) compared with students who identified as heterosexual (50% and 10%). Overall, students experienced insecurity via parental job loss (29%), personal job loss (22%), and hunger (24%). Disparities by sex and by race and ethnicity also were noted. Understanding health disparities and student disruptions and adverse experiences as interconnected problems can inform school and community initiatives that promote adolescent health and well-being. With community support to provide coordinated, cross-sector programming, schools can facilitate linkages to services that help students address the adverse experiences that they faced during the ongoing COVID-19 pandemic. Public health and health care professionals, communities, schools, families, and adolescents can use these findings to better understand how students' lives have been affected during the pandemic and what challenges need to be addressed to promote adolescent health and well-being during and after the pandemic.</p>","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":"50 1","pages":"28-34"},"PeriodicalIF":0.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8979601/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91155631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oakmoss Exhibits Antihyperglycemic Activity in Streptozotocin-Induced Diabetic Rats.","authors":"Ayoub Amssayef, Ismail Bouadid, Mohamed Eddouks","doi":"10.2174/1871529X22666220316100022","DOIUrl":"10.2174/1871529X22666220316100022","url":null,"abstract":"<p><strong>Aims: </strong>The study aimed to assess the antidiabetic effect of Oakmoss.</p><p><strong>Background: </strong>Lichens species are dual organisms consisting of a mycobiont (Fungi) and a photoautotrophic partner (Algae). They are widely used in traditional medicine as a treatment against diabetes.</p><p><strong>Objective: </strong>This study was designed to assess the antihyperglycemic activity as well as the antihyperlipidemic capacity of Oakmoss (Evernia prunastri (L.)) in normal and streptozotocin(STZ)-induced diabetic rats.</p><p><strong>Methods: </strong>This study has evaluated the effects of aqueous extract of Oakmoss at a dose of 60 mg/kg on blood glucose levels and lipid profile in normal and STZ-induced diabetic rats. Histopathological examination of liver, determination of glycogen content in liver and skeletal muscles (EDL and soleus), antioxidant activity, and phytochemical investigation were also performed.</p><p><strong>Results: </strong>Both single and repeated oral doses of Oakmoss (60 mg/kg) produced a significant reduction of blood glucose, triglycerides and very low-density lipoprotein (VLDL) levels in diabetic rats. Furthermore, repeated oral administration of Oakmoss during 7 days ameliorated the liver function by increasing its glycogen content and improving its histological architecture in treated diabetic rats. In addition, the aqueous extract of Oakmoss exhibited an antioxidant activity and showed richness in certain phytochemicals especially in phenolic acids and flavonoids.</p><p><strong>Conclusion: </strong>Oakmoss, a lichen species, exhibits a potential effect on improving hyperglycemia and hypertriglyceridemia in diabetic rats.</p>","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91178900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hypersurfaces of the nearly Kähler twistor spaces $mathbb{C}mathrm{P}^3$ and ${mathbb{F}_{1,2}}$","authors":"G. Deschamps, E. Loubeau","doi":"10.2748/tmj.20200930","DOIUrl":"https://doi.org/10.2748/tmj.20200930","url":null,"abstract":"","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42433851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laplacian comparison theorem on Riemannian manifolds with modified $m$-Bakry-Emery Ricci lower bounds for $mleq1$","authors":"K. Kuwae, Toshiki Shukuri","doi":"10.2748/tmj.20201028","DOIUrl":"https://doi.org/10.2748/tmj.20201028","url":null,"abstract":"In this paper, we prove a Laplacian comparison theorem for non-symmetric diffusion operator on complete smooth n-dimensional Riemannian manifold having a lower bound of modified m-Bakry-Émery Ricci tensor under m ≤ 1 in terms of vector fields. As consequences, we give the optimal conditions for modified m-Bakry-Émery Ricci tensor under m ≤ 1 such that the (weighted) Myers’ theorem, Bishop-Gromov volume comparison theorem, Ambrose-Myers’ theorem, Cheng’s maximal diameter theorem, and the Cheeger-Gromoll type splitting theorem hold. Some of these results were well-studied for m-Bakry-Émery Ricci curvature under m ≥ n ([19, 21, 27, 33]) or m = 1 ([34, 35]) if the vector field is a gradient type. When m < 1, our results are new in the literature.","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45360638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Counting rooted spanning forests for circulant foliation over a graph","authors":"L. Grunwald, Young Soo Kwon, I. Mednykh","doi":"10.2748/tmj.20210810","DOIUrl":"https://doi.org/10.2748/tmj.20210810","url":null,"abstract":"In this paper, we present a new method to produce explicit formulas for the number of rooted spanning forests f(n) for the infinite family of graphs Hn = Hn(G1, G2, . . . , Gm) obtained as a circulant foliation over a graph H on m vertices with fibersG1, G2, . . . , Gm. Each fiber Gi = Cn(si,1, si,2, . . . , si,ki) of this foliation is the circulant graph on n vertices with jumps si,1, si,2, . . . , si,ki . This family includes the family of generalized Petersen graphs, I-graphs, sandwiches of circulant graphs, discrete torus graphs and others. The formulas are expressed through Chebyshev polynomials. We prove that the number of rooted spanning forests can be represented in the form f(n) = p f(H)a(n)2, where a(n) is an integer sequence and p is a prescribed natural number depending on the number of odd elements in the set of si,j. Finally, we find an asymptotic formula for f(n) through the Mahler measure of the associated Laurent polynomial.","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47572436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The commutators of Bochner-Riesz operators for elliptic operators","authors":"Peng Chen, X. Tian, Lesley A. Ward","doi":"10.2748/tmj.20200415","DOIUrl":"https://doi.org/10.2748/tmj.20200415","url":null,"abstract":"","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47156781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On localization for cubical higher Chow groups","authors":"Jinhyung Park","doi":"10.2748/tmj.20211221","DOIUrl":"https://doi.org/10.2748/tmj.20211221","url":null,"abstract":"We give a purely cubical argument for the localization theorem for the cubical version of higher Chow groups.","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42118199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New characterizations of the helicoid in a cylinder","authors":"Eunjoo Lee","doi":"10.2748/tmj.20210713","DOIUrl":"https://doi.org/10.2748/tmj.20210713","url":null,"abstract":"This paper characterizes a compact piece of the helicoid HC in a solid cylinder C ⊂ R from the following two perspectives. First, under reasonable conditions, HC has the smallest area among all immersed surfaces Σ with ∂Σ ⊂ d1 ∪ d2 ∪ S, where d1 and d2 are the diameters of the top and bottom disks of C and S is the side surface of C. Second, other than HC , there exists no minimal surface whose boundary consists of d1, d2, and a pair of rotationally symmetric curves γ1, γ2 on S along which it meets S orthogonally. We draw the same conclusion when the boundary curves on S are a pair of helices of a certain height.","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42177017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Higher genus nonorientable maximal surfaces in the Lorentz-Minkowski 3-space","authors":"S. Fujimori, Shinobu Kaneda","doi":"10.2748/tmj.20210907b","DOIUrl":"https://doi.org/10.2748/tmj.20210907b","url":null,"abstract":"We study nonorientable maximal surfaces in Lorentz-Minkowski 3-space. We prove some existence results for surfaces of this kind with high genus and one end.","PeriodicalId":54427,"journal":{"name":"Tohoku Mathematical Journal","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43823430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}