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Probing turbulence in galaxies with fast radio burst scintillation

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Science China(Physics,mechanics & Astronomy) 2024年第1期67卷 177-178页

作者： James m.Cordes Department of Astronomy the Cornell Center for Astrophysics and Planetary ScienceCornell UniversityIthaca NY 14853USA

Interstellar scintillation(ISS)is a well-known phenomenon observed from pulsars in the milky Way.It comprises intensity variations vs.time and frequency caused by constructive and destructive interference from multipath propagation,which is due to diffraction from fluctuations in electron density in the interstellar medium(ISm)on scales as small as~100 km.These density fluctuations appear to be part of a turbulence process combined with discrete structures in electron density from other astrophysical processes;together these fluctuations extend to scales of pc or larger.

关键词： scales galaxies turbulence

Effect of special types of bread with select herbal components on postprandial glucose levels in diabetic patients

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World Journal of Diabetes 2024年第4期15卷 664-674页

作者： Drasko m Gostiljac Srdjan S Popovic Vesna Dimitrijevic-Sreckovic Sasa m Ilic Jelena A Jevtovic Dragan m Nikolic Ivan A Soldatovic Clinic for Endocrinology Diabetes and Metabolic DiseasesUniversity Clinical Centre of SerbiaBelgrade 11000Serbia Faculty of medicine University of BelgradeBelgrade 11000Serbia Clinic for Gastroenterology and Hepatology University Clinical Centre of SerbiaBelgrade 11000Serbia Clinic for Endocrinology Diabetes and Metabolic Diseases-Laboratory for Human Pancreatic Islets CultureUniversity Clinical Centre of SerbiaBelgrade 11000Serbia

BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(T2Dm)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food with various biologically active substances of herbal origin,so we formulated an herbal mixture that can be used as a supplement for a special type of bread(STB)to achieve better effects on postprandial glucose and insulin levels in patients with T2Dm.AIm To compare organoleptic characteristics and effects of two types of bread on postprandial glucose and insulin levels in T2Dm patients.mETHODS This trial included 97 patients with T2Dm.A parallel group of 16 healthy subjects was also investigated.All participants were given 50 g of rye bread and the same amount of a STB with an herbal mixture on 2 consecutive days.Postprandial blood glucose and insulin levels were compared at the 30^(th),60^(th),90^(th) and 120th min.A questionnaire was used for subjective estimation of the organoleptic and satiety features of the two types of bread.RESULTS Compared to patients who consumed rye bread,significantly lower postprandial blood glucose and insulin concentrations were found in T2Dm patients who consumed STB.No relevant differences were found among the healthy subjects.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.CONCLUSION STB have better effects than rye bread on postprandial glucoregulation in T2Dm patients.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.Therefore,STB can be recommended for nutrition in T2Dm patients.

关键词： Special types of bread Postprandial glucoregulation Insulin Nutrition Type 2 diabetes mellitus

Overcoming geographical and socioeconomic limitations in colorectal cancer screening

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1683-1689页

作者： Sofia Rozani Panagis m Lykoudis School of medicine National and Kapodistrian University of AthensAthens 11527Greece Division of Surgery and Interventional Science University College LondonLondon WC1E 6BTUnited Kingdom

Despite colorectal cancer’s(CRC)high global incidence,residents of low-and middle-income countries,as well as low-income minorities in advanced economies have low screening rates.Observational studies demonstrate that in these groups higher incidence of CRC is observed,yet screening rates remain low for consistent reasons.Low income,low educational background,and lack of awareness in combination with inadequate social security of certain population groups impede access and compliance rates to CRC screening.On the other hand,despite the global availability of multiple screening approaches(colonoscopy,sigmoidoscopy,faecal occult blood test,faecal immunochemical test,computed tomography-colonography,etc.)with proven diagnostic validity,many low-income countries still lack established screening programs.The absence of screening guidelines in these countries along with the heterogeneity of guidelines in the rest of the world,demonstrate the need for global measures to tackle this issue comprehensively.An essential step forward is to develop a global approach that will link specific elements of screening with the incidence and available resources in each country,to ensure the achievement of at least a minimum screening program in low-income countries.Utilizing cheaper,cost-effective techniques,which can be carried out by less specialized healthcare providers,might not be equivalent to endoscopy for CRC screening but seems more realistic for areas with fewer resources.Awareness has been highlighted as the most pivotal element for the effective implementation of any screening program concerning CRC.moreover,multiple studies have demonstrated that outreach strategies and community-based educational programs are associated with encouraging outcomes,yet a centrally coordinated expansion of these programs could provide more consistent results.Additionally,patient navigator programs,wherever implemented,have increased CRC screening and improved follow-up.Therefore,global coordination and patient education seem to be the main

关键词： Colorectal cancer Screening Low-and middle-income countries Socioeconomic disparities Cancer

Poly(A)-specific RNase(PARN)generates and regulates miR-125a-5p 3’-isoforms,displaying an altered expression in breast cancer

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1805-1807页

作者： Luisa Tomasello Shoshanah m.Holub Giovanni Nigita Rosario Distefano Carlo m.Croce Department of Cancer Biology and Genetics The Ohio State UniversityColumbusOHUSA Department of Internal medicine Division of HematologyThe Ohio State UniversityColumbusOHUSA

Dear Editor,microRNAs(miRNAs)are small non-coding RNAs crucial for post-transcriptional gene regulation,processed from primary miRNA transcripts by Drosha and Dicer.1 Latest advancements in Next Generation Sequencing highlighted the existence of miRNA isoforms(isomiRs)resulting from alternative processing,RNA editing,or post-transcriptional modifications.

关键词： breast cancer advancement

molecular mechanisms underlying SARS-CoV-2 hepatotropism and liver damage

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World Journal of Hepatology 2024年第1期16卷 1-11页

作者： Jorge Quarleri m Victoria Delpino Instituto de Investigaciones Biomédicas en Retrovirus y Sida(INBIRS) Universidad de Buenos Aires(UBA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Buenos Aires 1121Argentina

In coronavirus disease 2019(COVID-19),severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)primarily targets the respiratory system,but evidence suggests extrapulmonary organ involvement,notably in the liver.Viral RNA has been detected in hepatic tissues,and in situ hybridization revealed virions in blood vessels and endothelial cells.Electron microscopy confirmed viral particles in hepatocytes,emphasizing the need for understanding hepatotropism and direct cytopathic effects in COVID-19-related liver injury.Various factors contribute to liver injury,including direct cytotoxicity,vascular changes,inflammatory responses,immune reactions from COVID-19 and vaccinations,and druginduced liver injury.Although a typical hepatitis presentation is not widely documented,elevated liver biochemical markers are common in hospitalized COVID-19 patients,primarily showing a hepatocellular pattern of elevation.Long-term studies suggest progressive cholestasis may affect 20%of patients with chronic liver disease post-SARS-CoV-2 infection.The molecular mechanisms underlying SARS-CoV-2 infection in the liver and the resulting liver damage are complex.This“Editorial”highlights the expression of the Angiotensin-converting enzyme-2 receptor in liver cells,the role of inflammatory responses,the impact of hypoxia,the involvement of the liver's vascular system,the infection of bile duct epithelial cells,the activation of hepatic stellate cells,and the contribution of monocyte-derived macrophages.It also mentions that pre-existing liver conditions can worsen the outcomes of COVID-19.Understanding the interaction of SARS-CoV-2 with the liver is still evolving,and further research is required.

关键词： SARS-CoV-2 COVID-19 Hepatotropism Angiotensin-converting enzyme-2

Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： m.Grandin H.K.Connor S.Hoilijoki m.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis m.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight Center GreenbeltMD20771USA Space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The Solar wind magnetosphere Ionosphere Link Explorer(SmILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by SmILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SmILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can resu

关键词： magnetosphere magnetosheath numerical simulation SmILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol m.N.Saridede S.S.Kaplan m.S.Sonmez Department of metallurgical and materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and materials Science Stevens Institute of TechnologyNew JereyUSA Department of metallurgical and materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent lamp.and the yields were compared.In the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were investigated.The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 min.Activation energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction controlled.moreover,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed model.Concurrently,mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method

A FLEXIBLE OBJECTIVE-CONSTRAINT APPROACH AND A NEW ALGORITHm FOR CONSTRUCTING THE PARETO FRONT OF mULTIOBJECTIVE OPTImIZATION PROBLEmS

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Acta mathematica Scientia 2024年第2期44卷 702-720页

作者： N.HOSEINPOOR m.GHAZNAVI Faculty of mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

The role of N-glycosylation in cancer

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1098-1110页

作者： Yu Lin David m.Lubman Department of Surgery University of Michigan Medical CenterAnn ArborMI 48109USA

Despite advances in understanding the development and progression of cancer in recent years,there remains a lack of comprehensive characterization of the cancer glycoproteome.Glycoproteins play an important role in medicine and are involved in various human disease conditions including cancer.Glycan-moieties participate in fundamental cancer processes like cell signaling,invasion,angiogenesis,and metastasis.Aberrant N-glycosylation significantly impacts cancer processes and targeted therapies in clinic.Therefore,understanding N-glycosylation in a tumor is essential for comprehending disease progression and discovering anti-cancer targets and biomarkers for therapy monitoring and diagnosis.This review presents the fundamental process of protein N-glycosylation and summarizes glycosylation changes in tumor cells,including increased terminal sialylation,N-glycan branching,and corefucosylation.Also,the role of N-glycosylation in tumor signaling pathways,migration,and metabolism are discussed.Glycoproteins and glycopeptides as potential biomarkers for early detection of cancer based on site specificity have been introduced.Collectively,understanding and exploring the cancer glycoproteome,along with its role in medicine,implication in cancer and other human diseases,highlights the significance of N-glycosylation in tumor processes,necessitating further research for potential anticancer targets and biomarkers.

关键词： N-Glycosylated proteins Cancer signaling Cancer angiogenesis Cancer metabolism Cancer biomarkers