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A comprehensive review of genetic causes of obesity

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World Journal of Pediatrics 2024年第1期20卷 26-39页

作者： Marcio Jose Concepcion-Zavaleta Juan Eduardo Quiroz-Aldave Maria del Carmen Durand-Vasquez Elman Rolando Gamarra-Osorio Juan del Carmen Valencia de la Cruz Claudia Mercedes Barrueto-Callirgos Susan Luciana Puelles-Leon Elena de Jesus Alvarado-Leon Frans Leiva-Cabrera Francisca Elena Zavaleta-Gutierrez Luis Alberto Concepcion-Urteaga Jose Paz-Ibarra Universidad Cientifica del Sur Bolivar 2150 AvenuePueblo Libre15084LimaPeru division of Medicine Hospital de Apoyo ChepénChepenPeru division of Family Medicine Hospital de Apoyo ChepénChepenPeru division of Endocrinology Hospital Victor Lazarte EchegarayTrujilloPeru division of Pediatrics Hospital de Apoyo ChepenChepenPeru division of Internal Medicine Hospital de Apoyo ChepenChepenPeru division of Genetics Universidad Nacional de TrujilloTrujilloPeru division of Neonatology Hospital Belen de TrujilloTrujilloPeru division of Internal Medicine Universidad Nacional de TrujilloTrujilloPeru Department of Medicine School of MedicineUniversidad Nacional Mayor de San MarcosLimaPeru

Background Obesity is a multifactorial chronic disease with a high,increasing worldwide *** causes account for 7%of the cases in children with extreme *** sources This narrative review was conducted by searching for papers published in the PubMed/MEDLINE,Embase and SciELO databases and included 161 *** search used the following search terms:"obesity","obesity and genetics","leptin","Prader-Willi syndrome",and"melanocortins".The types of studies included were systematic reviews,clinical trials,prospective cohort studies,cross-sectional and prospective studies,narrative reviews,and case *** The leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body ***,several important aspects of the pathophysiology of obesity remain *** causes of obesity can be grouped into syndromic,monogenic,and polygenic causes and should be assessed in children with extreme obesity before the age of 5 years,hyperphagia,or a family history of extreme obesity.A microarray study,an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this *** are three therapeutic levels:lifestyle modifications,pharmacological treatment,and bariatric *** Genetic study technologies are in constant development;however,we are still far from having a personalized approach to genetic causes of obesity.A significant proportion of the affected individuals are associated with genetic causes;however,there are still barriers to its approach,as it continues to be underdiagnosed.

关键词： Leptin Melanocortin Obesity Prader-Willi syndrome Precision medicine

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： G.Murali division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called Geopolymer based ultra-highperformance concrete(GUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of GUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of GUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in GUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,GUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre Geopolymer Silica fume Alkaline activators

Mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PTFE)

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Friction 2024年第5期12卷 997-1015页

作者： Pontus JOHANSSON P.MARKLUND M.BJORLING Y.SHI division of Machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/PTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. Moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/PTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/PTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/PTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. Moreover, a loosely adhered tribofilm was observed on top of the CF/PTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere

A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1476-1484页

作者： Zirui Chen Jingchuan Tang Zongyu Zuo Seventh Research division Beihang University(BUAA)Beijing 100191China IEEE

The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled *** this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol ***,the interdependence among the pre-scribed parameters is *** validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach.

关键词： Guiding vector field non-holonomic vehicle path following prescribed performance sliding mode control

New approach for particle size and shape analysis of iron-based oxygen carriers at multiple oxidation states

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Particuology 2024年第7期90卷 493-503页

作者： Victor Purnomo Marcelo Dal Belo Takehara Robin Faust Lidiya Abdisa Ejjeta Henrik Leion division of Energy and Materials Department of Chemistry and Chemical EngineeringChalmers University of TechnologyGöteborg 41258Sweden division of Energy Science Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleå97187Sweden

One of the crucial issues in the chemical looping technology lies in its bed material:the oxygen *** size analysis of an oxygen carrier is important since in a fluidized bed the material can only work well within a specific size *** the favorable size ranges for oxygen carrier materials have already been reported,none of the published studies has analyzed the particle size and shape of oxygen carriers in ***,the effect of oxygen carriers'oxidation degree on such properties has not been considered *** study aimed to report the particle size and shape analysis of five iron-based oxygen carriers,one natural ore,one synthetic material,and three residue products,at different oxidation degrees using dynamic image analysis(DIA).The oxygen carriers were prepared at different mass conversion degrees in a fluidized bed batch *** size distribution,sphericity,and aspect ratio of the oxygen carrier particles were examined experimentally using a Camsizer *** results show that the DIA method was successfully able to analyze the particle size and shape of our oxygen carriers with satisfying accuracy for *** oxidation state of the investigated materials seems to only affect the particle size and shape of oxygen carriers to a minor ***,exposures to redox cycles in a fluidized bed reactor may alter the particle size and shape of most oxygen carriers.

关键词： Oxygen carrier Size and shape analysis Dynamic image analysis Oxidation state Fluidized bed Chemical looping

Prostate health index can stratify patients with Prostate Imaging Reporting and Data System score 3 lesions on magnetic resonance imaging to reduce prostate biopsies

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Asian Journal of Andrology 2024年第1期26卷 20-24页

作者： John Shung-Lai Leung Wai-Kit Ma Brian Sze-Ho Ho Stacia Tsun-Tsun Chun Rong Na Yongle Zhan Chi-Yuen Ng Chi-Ho Ip Ada Tsui-Lin Ng Yiu-Chung Lam division of Urology Department of SurgeryQueen Mary HospitalUniversity of Hong KongHong KongChina division of Urology Department of SurgeryPrincess Margaret HospitalHongKongChina

We aim to evaluate prostate health index as an additional risk-stratification tool in patients with Prostate Imaging Reporting and Data System score 3 lesions on multiparametric magnetic resonance *** with biochemical or clinical suspicion of having prostate cancer who underwent multiparametric magnetic resonance imaging in two tertiary centers(Queen Mary Hospital and Princess Margaret Hospital,Hong Kong,China)between January 2017 and June 2022 were ***-magnetic resonance imaging fusion biopsies were performed after prostate health index *** who only had Prostate Imaging Reporting and Data System score 3 lesions were further stratified into four prostate health index risk groups and the cancer detection rates were *** of the 747 patients,47.3%had Prostate Imaging Reporting and Data System score 3 lesions *** detection rate of clinically significant prostate cancer in this group was 15.0%.The cancer detection rates of clinically significant prostate cancer had statistically significant differences:5.3%in prostate health index<25.0,7.4%in prostate health index 25.0-34.9,17.9%in prostate health index 35.0-54.9,and 52.6%in prostate health index≥55.0(P<0.01).Among the patients,26.9%could have avoided a biopsy with a prostate health index<25.0,at the expense of a 5.3%risk of missing clinically significant prostate *** health index could be used as an additional risk stratification tool for patients with Prostate Imaging Reporting and Data System score 3 *** could be avoided in patients with low prostate health index,with a small risk of missing clinically significant prostate cancer.

关键词： biopsy fusion biopsy magnetic resonance imaging prostate cancer prostate health index

Thermal stability improvement and microstructure optimization of high cobalt content Nd-Fe-B magnets via terbium grain boundary diffusion

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Journal of Rare Earths 2024年第8期42卷 1531-1538,I0004页

作者： Jiyuan Xu Ruiyang Meng Jing Liu Jiateng Zhang Rui Han Yikun Fang Shengzhi Dong Wei Li division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China

The substitution of Fe by Co in the 2:14:1 phase is an effective method to increase the Curie temperature and enhance the thermal stability of the Nd-Fe-B ***,the accumulation of Co ele ment at the grain boundaries(GBs) changes the GBs from nonmagnetic to ferromagnetic and causes the thinlayer GBs to become rare,In this paper,the method of diffusing Tb element was chosen to improve the microstructure and temperature stability of high-Co *** original sintered Nd_(28.5)Dy_(3)-CO_(x)e_(bal)M_(0.6)B_(i)(x=0,6 wt%,12 wt%;M = Cu,Al,Zr) magnets with different Co contents were diffused with Tb by grain boundary diffusion(GBD).After GBD,high-Co magnets exhibit more continuously distributed thin-layer GBs,and their thermal stability is significantly *** high-Co magnets(x=6 wt%),the absolute value of the temperature coefficient of coercivity decreases from 0.603%/K to0.508%/K in the temperature range of 293-413 K,that of remanence decreases from 0.099%/K to 0.091%/K,and the coercivity increases from 18.44 to 25.04 *** electron microscopy(TEM)characterization reveals that there are both the 1:2 phase and the amorphous phase in the high-Co magnet before and after GBD,EDS elemental analysis shows that Tb element is more likely to preferentially replace the rare earth elements in the 2:14:1 main phase than in the 1:2 phase and the amorphous *** concentration of Tb at the edge of the main phase is much higher than that in the 1:2phase and amorphous phase,which is beneficial to the improvement of the *** preferential replacement of Tb elements at the edge of the 2:14:1 phase and thin-layer GBs with a more continuous distribution are synergistically responsible for improving the thermal stability of high-Co *** study indicates that GBD is an effective method to improve the microstructure and thermal stability of high-Co magnets.

关键词： Nd-Fe-B magnets Coercivity Grain boundary diffusion Thermal stability Micro structure Rare earths

Diagnostic and prognostic performances of GALAD score in staging and 1-year mortality of hepatocellular carcinoma: A prospective study

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World Journal of Gastroenterology 2024年第17期30卷 2343-2353页

作者： Oraphan Jitpraphawan Witchakorn Ruamtawee Mala Treewatchareekorn Supatsri Sethasine division of Gastroenterology and Hepatology Department of MedicineNavamindradhiraj UniversityDusit 10300BangkokThailand Clinical Research Center Research Facilitation DivisionNavamindradhiraj UniversityDusit 10300BangkokThailand division of Clinical Chemistry and Immunology Navamindradhiraj UniversityDusit 10300BangkokThailand

BACKGROUND The GALAD score has improved early hepatocellular carcinoma(HCC)detection *** role of the GALAD score in staging and predicting tumor characteristics or clinical outcome of HCC remains of particular *** To determine the diagnostic/prognostic performances of the GALAD score at various phases of initial diagnosis,tumor features,and 1-year mortality of HCC and compare the performance of the GALAD score with those of other serum *** This prospective,diagnostic/prognostic study was conducted among patients with newly diagnosed HCC at the liver center of Vajira *** patients had HCC staging allocation using the Barcelona Clinic Liver Cancer(BCLC)***,HCC etiology,and HCC features were *** and the GALAD score were obtained at *** performance of the GALAD score and biomarkers were prospectively *** Exactly 115 individuals were diagnosed with *** GALAD score increased with disease *** BCLC-0/A and BCLC-B/C/D,the GALAD score predicted HCC staging with an area under the curve(AUC)of 0.868(95%CI:0.80–0.93).For identifying the curative HCC,the AUC of GALAD score was significantly higher than that of Alpha-fetoprotein(AFP)(0.753)and Lens culinaris agglutinin-reactive fraction of AFP-L3(0.706),and as good as that of Protein induced by vitamin K absence-II(PIVKA-II)(0.897).For detecting aggressive features,the GALAD score gave an AUC of 0.839(95%CI:0.75–0.92)and significantly outperformed compared to that of AFP(0.761)and AFP-L3(0.697),with a trend of superiority to that of PIVKA-II(0.772).The performance to predict 1-year mortality of GALAD score(AUC:0.711,95%CI:0.60–0.82)was better than that of AFP(0.541)and as good as that of PIVKA-II(0.736).The optimal cutoff value of GALAD score was≥6.83,with a specificity of 72.63%for exhibiting substantial reduction in the 1-year *** The GALAD model can diagnose HCC at the curative stage,includin

关键词： Alpha-fetoprotein Barcelona clinic liver cancer GALAD score Hepatocellular carcinoma Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein Protein induced by vitamin K absence-II

Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 186-196页

作者： Sara Marijan Luka Pavic division of Materials Chemistry Ruđer Boskovic InstituteBijenicka 54HR-10000 ZagrebCroatia

Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 *** transition from a predominantly phosphate glass network(xanalyzed through modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic *** contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation *** high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)*** scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a

关键词： phosphate glasses glass-ceramics impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism