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Cool white light and tunable multicolor emission from Tb^(3+)/Dy^(3+)co-activated glasses under different excitations for WlEDs

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Journal of Rare Earths 2024年第1期42卷 46-56,I0002页

作者： l.Vijayalakshmi K.Naveen Kumar Jong Dae Baek Department of Automotive Engineering Yeungnam UniversityGyeongsanGyeongbuk38541Republic of Korea Department of Mechanical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

A set of co-doped(Tb^(3+)/Dy^(3+))lithium zinc borate(lZB)glasses were developed by melt *** structural evaluation was performed for synthesized glassy *** Dy^(3+)and Tb^(3+)individually doped glasses exhibit intense yellow and green luminescence bands at 575 nm(^(4)F_(9/2)→^(6)H_(13/2))and543 nm(^(5)D_(4)→^(7)F_(5)),*** sensitization effect of Dy^(3+)on Tb^(3+)was analyzed by increasing the Tb^(3+)content with respect to the optimum Dy^(3+)content(0.5 mol%)in Dy^(3+)/Tb^(3+).The spectral overlay of Dy^(3+)luminescence and Tb^(3+)absorption profiles,Dy^(3+)/Tb^(3+)Pl spectra under different excitations 352,362,376,and 385 nm,shortening decay lifetimes of Dy^(3+)in Dy^(3+)/Tb^(3+)co-activated glasses,energy transfer(ET)parameters,chromaticity coordinates and their corresponding correlated temperatures all help to explain ET from Dy^(3+)to Tb^(3+).At 385 nm of Dy^(3+)excitation,the optimized co-activated(0.5Dy^(3+)+1.0Tb^(3+)):lZB glass displays cool white light *** non-radiative ET from Dy^(3+)to Tb^(3+)is dominated by electric dipole-dipole interaction and its ET efficiency was calculated to be 63%.At the same time,reverse ET from Tb^(3+)to Dy^(3+)was also *** shift in color coordinates from dominant yellow to greenish-yellow,green and white light emission suggests that Dy^(3+)/Tb^(3+)coactivated lZB glasses can be a potential candidate for UV converted multicolor and white light emitting devices.

关键词： Rare earths Photoluminescence Energy transfer Spectral overlap Decay lifetime Multicolor emitting lEDs

Obstetrical specificities of Ivorian adolescent mothers on a single-center hospital series of 1040 cases

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Gynecology and Obstetrics Clinical Medicine 2022年第2期2卷 86-90页

作者： Edele Kacou Aka Apollinaire Horo Mohamed Fanny luc Olou Perel konan Abdoul koffi Ana Toure-Ecra Mamourou Kone Universite Felix Houphouet Boigny(FHB) Centre Hospitalier Universitaire de Yopougon-AbidjanService de Gynecologie-ObstetriqueAbidjanCote d’Ivoire

Overview and aim:The precocity of sexual intercourse among adolescent girls is a prominent source of unwanted ***,we aim to survey the past issues relating to the pregnancy,childbirth,and materno-fetal prognosis of Ivorian adolescent ***:We conducted a retrospsective study with adolescent group(n=1040)versus young adult group aged 20 to 24(n=736)over three years from1st January 2016 to 31rd December 2018 at the Department of Obstetrics and Gynecology at the University of Abidjan-Yopougon *** and fetal outcomes of the two groups were analyzed and compared by using Pearson's Chi2 tests and Fisher's exact tests,followed by multivariate analysis and logistic regression using Stata software version ***:The average age of adolescent girls in our study was 17.45 years(SD=1.39)and a minimum of 12 *** consulted less(Plater(Plts aged 20 to *** proportion of adolescent girls(47.6%)versus young adults(39.1%)who had underwent caesarean section was significantly higher(P=0.0004).These adolescents were 3.5-fold more likely to develop hypertension and its complications in the postpartum period and 2.5-fold more likely to contract a postpartum *** mortality was not significantly associated with adolescence(OR=0.52)(95%CI:0.22–1.19;P=0.0891).The risk of prematurity,early neonatal death,and neonatal admission were 2.02(95%CI:1.56–2.63;Plescence,***:Adolescent childbirth remains associated with a poor prognosis.

关键词： High-risk pregnancy Adolescent girl West Africa

Chronic active and atrophic gastritis as significant contributing factor to the development of gastric cystica profunda

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World Journal of Gastroenterology 2024年第17期30卷 2308-2310页

作者： Veronika Papp Pál Miheller Department of Surgery Transplantation and GastroenterologySemmelweis UniversityBudapest 1082Hungary

Gastric cystica profunda(GCP)is an uncommon but underestimated gastric *** precancerous potential determines its *** addition to previous mucosa injury due to operations,biopsy or polypectomy,chronic active and atrophic gastritis may also lead to the development of *** carefully examining the stomach and taking biopsy samples from the susceptible regions,the stage of atrophy can be *** atrophic gastritis is a risk factor for cancer evolvement and it can also contribute to GCPs *** frequently occur close to early gastric cancers(EGCs)or EGC can arise from the cystic *** resection is an effective and minimally invasive treat-ment in GCP.

关键词： Gastric cystica profunda Chronic active gastritis Atrophic gastritis Operative link for Gastritis Assessment staging Early gastric cancer Endoscopic resection

Time trends and outcomes of gastrostomy placement in a Swedish national cohort over two decades

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World Journal of Gastroenterology 2024年第10期30卷 1358-1367页

作者： Martin löfling Skogar Magnus Sundbom Department of Surgical Sciences Uppsala UniversityUppsala 75185Sweden

BACKGROUND Percutaneous endoscopic gastrostomy(PEG)and laparoscopically inserted gastrostomy have become the gold standard for adult patients and children,respectively,requiring long-term enteral nutrition ***-related mortality is a rare event,often reported to be zero in smaller *** data on 30-d mortality and long-term survival rates after gastrostomy placement are scarce in the *** To study the use of gastrostomies in Sweden from 1998-2019 and to analyze procedure-related mortality and short-term(long-term *** In this retrospective,population-based cohort study,individuals that had received a gastrostomy between 1998-2019 in Sweden were *** were identified in the Swedish National Patient Register,and survival analysis was possible by cross-referencing the Swedish Death *** cohort was divided into three age groups:Children(0-18 years);adults(19-64 years);and elderly(≥65 years).Kaplan-Meier with log-rank test and Cox regression were used for survival *** In total 48682 individuals(52%males,average age 60.9±25.3 years)were *** cohort consisted of 12.0%children,29.5%adults,and 58.5%*** increased use of gastrostomies was observed during the study period,from 13.7/100000 to 22.3/100000 individuals(Pled(about 800 to 1800/year),with a corresponding decrease in open gastrostomy(about 700 to 340/year).laparoscopic gastrostomy increased more than ten-fold(about 20 to 240/year).Overall,PEG,open gastrostomy,and laparoscopic gastrostomy constituted 70.0%(n=34060),23.3%(n=11336),and 4.9%(n=2404),***-related mortality was 0.1%(n=44)overall(PEG:0.05%,open:0.24%,laparoscopic:0.04%).The overall 30-d mortality rate was 10.0%(PEG:9.8%,open:12.4%,laparoscopic:1.7%)and decreased from 11.6%in 1998-2009 vs 8.5%in 2010-2019(Pl rates for children,adults,and elderly were 93.7%,67.5%,a

关键词： Gastrostomy Percutaneous endoscopic gastrostomy Dysphagia Enteral nutrition long-term Survival Complication

Distributed swarm control for multi-robot systems inspired by shepherding behaviors

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Science China(Technological Sciences) 2024年第7期67卷 2191-2202页

作者： SUN GuiBin GU HaiBo lÜJinHu School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Zhongguancun laboratory Beijing 100094China

Swarming behaviors play an eminent role in both biological and engineering research, and show great potential applications in many emerging fields. Traditional swarming models still lack integrity, uniformity, and stability in swarm forming processes,resulting in fragmentation and void phenomena. Inspired by the shepherding behaviors observed in nature, we propose an integrated negotiation-control scheme for distributed swarm control of massive robots. The core idea of this scheme is that the robots at the boundary of the group herd the internal robots to form an equilibrium swarm. For this purpose, we introduce a concept of virtual group center towards which boundary robots herd internal robots. Then, a distributed negotiation mechanism is designed to allow each robot to negotiate the virtual group center only through local interactions with its neighbors. After that, we propose a shepherding-inspired swarm control law to drive a group of robots to form an integrated, uniform, and stable configuration from any initial states. Both numerical and flight simulations are presented to verify the effectiveness of our proposed swarm control scheme.

关键词： swarm control multi-robot system negotiation-control scheme shepherding behavior

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Tomographic reconstruction of the Earth’s magnetosheath from multiple spacecraft:a theoretical study

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Earth and Planetary Physics 2024年第1期8卷 204-214页

作者： A.M.Jorgensen TianRan Sun Y.Huang l.li R.Xu l.Dai Chi Wang New Mexico Institute of Mining and Technology SocorroNMUSA National Space Science Center Chinese Academy of SciencesBeijing 100190China Tsinghua University Beijing 100084China

Following our earlier work on tomographic reconstruction of the magnetosheath soft X-ray emissions with superposed epoch analysis of many images recorded from a single spacecraft we now explore the instantaneous reconstruction of the magnetosheath and magnetopause using a few images recorded simultaneously from a few *** work is motivated by the prospect of possibly having two or three soft X-ray imagers in space in the coming years,and that many phenomena which occur at the magnetopause boundary,such as reconnection events and pressure pulse responses,do not lend themselves as well to superposed epoch *** the reconstruction is successful-which we demonstrate in this paper that it can be-this collection of imagers can be used to reconstruct the magnetosheath and magnetopause from a single image from each spacecraft,allowing for high time resolution *** this paper we explore the reconstruction using,two,three,and four *** show that the location of the subsolar point of the magnetopause can be determined with just two satellites,and that volume emissions of soft X-rays,and the shape of the boundary,can be reconstructed using three or more satellites.

关键词： magnetosheath tomography soft X-ray imaging SMIlE

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar Sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Stability and performance analysis of the compressed Kalman filter algorithm for sparse stochastic systems

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Science China(Technological Sciences) 2024年第2期67卷 380-394页

作者： lI RongJiang GAN Die XIE SiYu lüJinHu Key laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun laboratory Beijing 100049China School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic *** deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)*** algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional ***,the original high-dimensional sparse signals can be well recovered by a reconstruction *** ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and ***,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.

关键词： sparse signal compressed sensing Kalman filter algorithm compressed excitation condition stochastic stability tracking performance

Epidemiological Profile of Obesity among Adults Aged 21 to 65 Years living in Yopougon, Cocody and Abobo (District of Abidjan, Côte d’Ivoire)

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Open Journal of Endocrine and Metabolic Diseases 2023年第11期13卷 191-216页

作者： Ahoussi Attouo Josiane koffi koffi Bruno Koko Adjoumani Placide Ehoué Brou André konan Biology and Health laboratory Félix Houphou&#235t-Boigny University Abidjan C&#244te d’Ivoire National Council for Nutrition Food and Early Childhood Development Abidjan C&#244te d’Ivoire Animal Physiology Phytotherapy and Pharmacology Alassane Ouattara University Bouaké C&#244te d’Ivoire

Objective: The study aims to establish the epidemiological profile of obesity in Abidjan. Methods: It was a cross-sectional study carried out in Côte d’Ivoire with 349 volunteers aged 21 to 65 years old and living in 330 households located in Yopougon, Cocody and Abobo, three Municipalities in the city of Abidjan. Results: Out of 349 participants, 90 or 25.8% were declared obese according to BMI. Based on IMG, 62.8% of people had abnormally high body fat. Abdominal obesity was more common in Yopougon and Cocody than in Abobo. Relative to BMI, 36.1% of women were obese compared to 12.9% of men. The same observation was made with regard to the umbilical perimeter. Indeed, abdominal obesity was more observed in women with a rate of 52.6% compared to 11.6% in men. 35.6% of obese people have no level of education. According to the respondents, a very high proportion of weight gain occurred after the age of 10. It was between 10 and 21 years old in Yopougon and Cocody and between 18 and 21 years old in Abobo. More than 70% of obese people living in Yopougon, Cocody and Abobo would not consider obesity as a disease while 40.7% have said they were very little informed about obesity. Conclusion: Two major points have emerged from the examination of the data collected: 1) The prevalence of overweight and obesity remains very high in the three Communes of Abidjan. 2) The occurrence of obesity would be influenced by the sociodemographic characteristics of the populations. Also, updating these sociodemographic characteristics is essential to better adapt national strategies for obesity and overweight combating.

关键词： Epidemiological Profile Obesity Adult Abidjan Côte d’Ivoire