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CSI acquisition in RIS-assisted mobile communication systems

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National Science Review 2023年第8期10卷 33-47页

作者： Yu Han Wankai Tang Xiao Li michail matthaiou Shi Jin National Mobile Communications Research Laboratory Southeast University Centre for Wireless Innovation(CWI) Queen's University Belfast

Reconfigurable intelligent surface-(RIS) assisted mobile communication is a promising technological paradigm thanks to the attractive advantages of low cost and flexible control of electromagnetic ***, the low-cost features of RISs entail some fundamental challenges to the acquisition of channel state information(CSI), which is essential for the optimal RIS design. To tackle this problem, there have been extensive studies on CSI acquisition in RIS-assisted mobile communication systems, from the perspective of architectural improvement as well as specific mathematical solutions. This article aims to overview the existing works on CSI acquisition in RIS-assisted mobile communication systems.

关键词： channel estimation hybrid RIS implicit CSI RIS

Incidence, risk factors and clinical outcome of multidrug-resistant organisms after heart transplantation

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World Journal of Transplantation 2024年第2期14卷 107-118页

作者： Sophia Hatzianastasiou Paraskevas Vlachos Georgios Stravopodis Dimitrios Elaiopoulos Afentra Koukousli Josef Papaparaskevas Themistoklis Chamogeorgakis Kyrillos Papadopoulos Theodora Soulele Despoina Chilidou Kyriaki Kolovou Aggeliki Gkouziouta michail Bonios Stamatios Adamopoulos Stavros Dimopoulos Microbiology Department and Infection Control Office Onassis Cardiac Surgery CenterAthens 17674Greece Heart Transplantation Unit Onassis Cardiac Surgery CenterAthens 17674Greece Cardiac Surgery Intensive Care Unit Onassis Cardiac Surgery CenterAthens 17674Greece

BACKGROUND Transplant recipients commonly harbor multidrug-resistant organisms(MDROs),as a result of frequent hospital admissions and increased exposure to antimi-crobials and invasive *** To investigate the impact of patient demographic and clinical characteristics on MDRO acquisition,as well as the impact of MDRO acquisition on intensive care unit(ICU)and hospital length of stay,and on ICU mortality and 1-year mortality post heart *** This retrospective cohort study analyzed 98 consecutive heart transplant patients over a ten-year period(2013-2022)in a single transplantation *** was collected regarding MDROs commonly encountered in critical *** Among the 98 transplanted patients(70%male),about a third(32%)acquired or already harbored MDROs upon transplantation(MDRO group),while two thirds did not(MDRO-free group).The prevalent MDROs were Acinetobacter baumannii(14%),Pseudomonas aeruginosa(12%)and Klebsiella pneumoniae(11%).Compared to MDRO-free patients,the MDRO group was characterized by higher body mass index(P=0.002),higher rates of renal failure(P=0.017),primary graft dysfunction(10%vs 4.5%,P=0.001),surgical re-exploration(34%vs 14%,P=0.017),mechanical circulatory support(47%vs 26%P=0.037)and renal replacement therapy(28%vs 9%,P=0.014),as well as longer extracorporeal circulation time(median 210 vs 161 min,P=0.003).The median length of stay was longer in the MDRO group,namely ICU stay was 16 vs 9 d in the MDRO-free group(P=0.001),and hospital stay was 38 vs 28 d(P=0.006),while 1-year mortality was higher(28%vs 7.6%,log-rank-χ2:7.34).CONCLUSION Following heart transplantation,a predominance of Gram-negative MDROs was *** acquisition was associated with higher complication rates,prolonged ICU and total hospital stay,and higher post-transplantation mortality.

关键词： Heart transplantation Multi drug resistant organisms Transplantation complications Transplantation outcome

非洲最恐怖的生命禁区一百年里无人敢涉足的达洛尔

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环球人文地理 2024年第5期 96-103页

作者：李理 Vladislav Radek Benot ArtushFoto Lina dinozzaver michail mikhail cheremkin flickr

色彩绚丽的盐层让人称奇，强酸性的湖水腐蚀鞋子，车队时不时被袭击，还曾有游客被撕票……达洛尔深刻诠释了什么叫“越迷人的越危险”。达洛尔位于埃塞俄比亚东北角，被描述成一个鬼城。因为2005年之后，埃塞俄比亚中央统计局的人口报...

色彩绚丽的盐层让人称奇，强酸性的湖水腐蚀鞋子，车队时不时被袭击，还曾有游客被撕票……达洛尔深刻诠释了什么叫“越迷人的越危险”。达洛尔位于埃塞俄比亚东北角，被描述成一个鬼城。因为2005年之后，埃塞俄比亚中央统计局的人口报告中，就已没有此地区的人口数据。这里是世界上最遥远、最荒芜的地区之一，没有学校、没有商店，也没有公路，对外交通除了游客车队，就只有前往该地收集盐块的阿法尔人与骆驼。然而，这里的形势极不稳定，

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Unraveling the mechanisms of a giant coronary sinus

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Journal of Geriatric Cardiology 2023年第6期20卷 483-484页

作者： michail Kyrtsopoulos Apostolos Galatas Anastasios Kartas Cardiology Department AHEPA University HospitalAristotle University of ThessalonikiThessalonikiGreece

The coronary sinus(CS)is a tubular venous structure in the left atrioventricular groove that drains around 55% of the deoxygenated coronary arterial blood supply into the right atrium.[1,2]The CS,predominantly a small structure,can be significantly dilated leading to a condition known as giant *** CS is a clinically important but rare echocardiographic finding,which can be caused by a variety of factors.

关键词： coronary sinus arterial

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Emergency Hybrid Correction in a Newborn with Critical Aortic Valve Stenosis with Acute Pulmonary Edema in the First Hour after Birth

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Congenital Heart Disease 2023年第1期18卷 57-65页

作者： Vitaliy Suvorov Vladimir Zaitsev Nikolay Pilyugov Olga Tereshenko michail Komissarov Saint Petersburg State Pediatric Medical University Saint-PetersburgRussia

Critical aortic valve stenosis in newborns is the cause of a severe clinical condition with the onset of symptoms during first hours after *** present a clinical case of a successful surgical correction of a critical aortic stenosis using a hybrid method applied in a newborn during the first day of *** infant was diagnosed with a hypoplastic left heart complex with an intact atrial septum(aortic and mitral valves stenosis variant),that led to the cardiogenic shock and acute pulmonary *** procedure included bilateral banding of the pulmonary artery branches and atrioseptostomy with stenting of the interatrial *** surgery was performed through a median sternotomy.

关键词： Critical aortic valve stenosis hybrid correction hybrid Norwood bilateral banding hybrid Norwood procedure acute pulmonary edema intact atrial septum hypoplastic left heart complex

Technical note for intraoperative determination of proper acetabular cup size in primary total hip arthroplasty

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World Journal of Methodology 2024年第1期14卷 94-101页

作者： Panagiotis Karampinas John Vlamis Athanasios Galanis michail Vavourakis Anastasia Krexi Evangelos Sakellariou Christos Patilas Spiros Pneumaticos 3^(rd)Department of Orthopaedic Surgery National&Kapodistrian University of AthensKAT General HospitalAthens 14561Greece

BACKGROUND Selecting the optimal size of components is crucial when performing a primary total hip *** the accurate size of the acetabular component can occasionally be exacting,chiefly for surgeons with little experience,whilst the complications of imprecise acetabular sizing or over-reaming can be potentially *** To assist clinicians intraoperatively with a simple and repeatable tip in elucidating the ambivalence when determining the proper acetabular component size is not straightforwardly achieved,specifically when surgeons are inexperienced or preoperative templating is *** This method was employed in 263 operations in our department from June 2021 to December *** operations were performed by the same team of joint reconstruction surgeons,employing a typical posterior hip approach *** types of acetabular shells implanted were:The Dynasty®acetabular cup system(MicroPort Orthopedics,Shanghai,China)and the R3®acetabular system(Smith&Nephew,Watford,United Kingdom),which both feature cementless press-fit *** The mean value of all cases was calculated and collated with each *** distinguished as oversized an implanted acetabular shell when its size was>2 mm larger than the size of the acetabular size indicator reamer(ASIR)or when the implanted shell was larger than 4 mm compared to the preoperative planned *** median size of the implanted acetabular shell was 52(48–54)mm,while the median size of the preoperatively planned cup was 50(48–56)mm,and the median size of the ASIR was 52(50–54)*** correlation coefficient between ASIR size and implanted acetabular component size exhibited a high positive correlation with r=0.719(P<0.001).Contrariwise,intraoperative ASIR measurements precisely predicted the implanted cups’size or differed by only one size(2 mm)in 245 *** In our study,we demonstrated that the size of the first acetabular reamer not entering freely in the acetabular

关键词： Acetabular shell Total hip arthroplasty Hip Acetabulum Acetabular component Primary hip arthroplasty

Short vs long-course antibiotic therapy in adults with acute cholangitis:A systematic review,meta-analysis,and evidence quality assessment

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World Journal of Gastroenterology 2023年第19期29卷 3027-3039页

作者： Karampet Kasparian Chrysanthos D Christou Konstantinos Petidis michail Doumas Olga Giouleme Clinic of Oncology Gastroenterology and HematologyAlfried Krupp HospitalEssen 45131Germany Second Propedeutic Department of Internal Medicine Hippokration General HospitalAristotle University of ThessalonikiThessaloniki 54642Greece Department of Transplantation Surgery Hippokration General HospitalAristotle University of ThessalonikiThessaloniki 54642Greece

BACKGROUND Acute cholangitis(AC)constitutes an infection with increased mortality rates in the *** to new diagnostic tools and therapeutic methods,the mortality of AC has been significantly reduced *** initial antibiotic treatment of AC has been oriented to the most common pathogens connected to this ***,the optimal duration of the antibiotic treatment of AC is still *** To investigate if shorter-course antibiotic treatments could be similarly effective to long-course treatments in adults with *** This study constitutes a systematic review and meta-analysis of the existing literature concerning the duration of antibiotic therapy of AC and an assessment of the quality of the *** study was conducted in accordance with the recommendations of the Preferred Reporting Items for Systematic Review and *** studies were included in the systematic review,and eight were eligible for *** to heterogeneous duration cutoffs,three study-analysis groups were formed,with a cutoff of 2-3,6-7,and 14 *** A total of 2763 patients were included in the systematic review,and 1313 were accounted for the *** mean age was 73.66±14.67 years,and the male and female ratio was 1:*** significant differences were observed in the mortality rates of antibiotic treatment of 2-3 d,compared to longer treatments(odds ratio=0.78,95% confidence interval:0.23-2.67,I2=9%)and the recurrence rates and hospitalization length were also not different in all study *** Short-and long-course antibiotic treatments may be similarly effective concerning the mortality and recurrence rates of *** conclusions cannot be extracted concerning the hospitalization duration.

关键词： Acute cholangitis Antibiotic Short-course Long-course Antimicrobial Treatment duration

Single-center experience with Knee+^(TM) augmented reality navigation system in primary total knee arthroplasty

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World Journal of Orthopedics 2024年第3期15卷 247-256页

作者： Evangelos Sakellariou Panagiotis Alevrogiannis Fani Alevrogianni Athanasios Galanis michail Vavourakis Panagiotis Karampinas Panagiotis Gavriil John Vlamis Stavros Alevrogiannis The 3^(rd)Department of Orthopaedic Surgery National&Kapodistrian University of AthensKAT General HospitalAthens 14561Greece The 1^(st)Department of Orthopaedic Surgery National&Kapodistrian University of AthensAttikon General HospitalAthens 14561Greece Department of Anesthesiology KAT General HospitalAthens 14561Greece Department of Robotic Hip&Knee Orthopaedic Surgery Metropolitan General HospitalAthens 14561Greece

BACKGROUND Computer-assisted systems obtained an increased interest in orthopaedic surgery over the last years,as they enhance precision compared to conventional *** expansion of computer assistance is evolving with the employment of augmented ***,the accuracy of augmented reality navigation systems has not been *** To examine the accuracy of component alignment and restoration of the affected limb’s mechanical axis in primary total knee arthroplasty(TKA),utilizing an augmented reality navigation system and to assess whether such systems are conspicuously fruitful for an accomplished knee *** From May 2021 to December 2021,30 patients,25 women and five men,under-went a primary unilateral *** cases were excluded.A preoperative radiographic procedure was performed to evaluate the limb’s axial *** patients were operated on by the same team,without a tourniquet,utilizing three distinct prostheses with the assistance of the Knee+™augmented reality navigation system in every ***,the same radiographic exam protocol was executed to evaluate the implants’position,orientation and coronal plane *** recorded measurements in 3 stages regarding femoral varus and flexion,tibial varus and posterior ***,the expected values from the Augmented Reality system were *** we calculated the same values after each cut and finally,the same measurements were recorded radiolo-gically after the *** statistical analysis,Lin’s concordance correlation coefficient was estimated,while Wilcoxon Signed Rank Test was performed when *** A statistically significant difference was observed regarding mean expected values and radiographic mea-surements for femoral flexion measurements only(Z score=2.67,P value=0.01).Nonetheless,this difference was statistically significantly lower than 1 degree(Z score=-4.21,P value<0.01).In terms of discrepancies in the calculations of

关键词： Augmented reality Orthopedics Total knee arthroplasty Robotics Knee Navigation

Pre-processing for time domain image formation in SS-BSAR system

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Journal of Systems Engineering and Electronics 2012年第6期23卷 875-880页

作者： michail Antoniou Mikhail Cherniakov School of Electronic Electrical and Computer EngineeringUniversity of BirminghamBirmingham B15 2TTUK

A pre-processing procedure is designed for a space-surface bistatic synthetic aperture radar （SS-BSAR） system when a time domain image formation algorithm is employed. Three crucial technical issues relating to the procedure are fully discussed. Firstly, unlike image formation algorithms operating in the frequency domain, a time domain algorithm requires the accurate global navigation satellite system （GNSS） time and position. This paper proposes acquisition of this information using a time-and-spatial transfer with precise ephemeris and interpolation. Secondly, synchronization errors and compensation methods in SS-BSAR are analyzed. Finally, taking the non-ideal factors in the echo and the compatibility of image formation algorithms into account, a matched filter based on the minimum delay is constructed. Experimental result using real data suggest the pre-processing is functioning properly.

关键词： image formation space-surface bistatic syntheticaperture radar (SS-BSAR) global navigation satellite system(GNSS) synchronization range compression.

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