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Quantification of skid resistance seasonal variation in asphalt pavements

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第2期7卷 237-248页

作者： christina plati Maria Pomoni Konstantina Georgouli Laboratory of Pavement Engineering School of Civil EngineeringNational Technical University of Athens(NTUA)Athens 15773Greece

The present study deals with the quantification of skid resistance seasonal variation in asphalt pavements.Consequently,skid resistance data were collected twice per year(after"wet"and"dry"seasons)along four trial sections of an urban highway with a GripTester system(during a six-year field experiment).For the estimation of a percentage reference change(%)between wet and dry skid resistance data,a methodology is developed based on distribution fitting of the percentage change of skid resistance index due to seasonal variation impact.The outcome of the analysis is applied and successfully validated through a set of skid resistance data collected from an interurban highway pavement section with different traffic and environmental conditions.As such the developed methodology can be considered as a promising tool for accommodating the seasonal variation of skid resistance.Further,the resulting percentage reference change(%)enables the estimation of skid resistance level for the dry period based on the wet period measurements.Overall,it seems that the proposed quantification process may constitute a practical yet efficient tool for road authorities and highway operators on how to estimate the effect of seasonal variation on skid resistance levels and schedule well-ahead necessary actions for enhancing driving safety.

关键词： Asphalt pavement Skid resistance Seasonal variation Quantification Road safety

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Autonomous vehicles wheel wander: Structural impact on flexible pavements

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第3期8卷 388-398页

作者： Konstantina Georgouli christina plati Andreas Loizos Department of Transportation Planning and Engineering School of Civil EngineeringNational Technical University of AthensZografou 15773Greece

Autonomous vehicles(AVs), including trucks, are already available and their adoption is coming at a rapid pace. Despite the fact that this new transportation technology will travel on existing pavement infrastructure assets, the study and investigation of the AVs structural impact on pavements has not reached the same level of attention and maturity as other related research areas. Considering the extensive investment on pavement construction and maintenance, the necessity to fully understand these impacts in the long term, is becoming evident. The present paper presents and discusses currently published relevant research and findings on the quantification of the wheel wander potential impact,both negative and positive, offering potential insightful future areas of enquiry to help mold and shape future research for this emerging field. The paper focuses on the impact of the AVs zero lateral wheel wander on both new flexible pavement design and the damage accumulation within existing flexible pavement structures. Other wheel wander distributions(normal, uniform, etc.) are investigated as well. The outcome and findings are that the AVs zero lateral wheel wander has a definable negative structural impact on flexible pavement structures in comparison to current human-driven(non-autonomous) vehicles that tend to follow a normal lateral wheel wander distribution. However, under certain defined conditions(optimal wheel wander distribution), the pavement service life can be potentially extended.

关键词： Road engineering Autonomous vehicles Wheel wander Pavement design Pavement performance

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Effects of early postnatal gastric and colonic microbiota transplantation on piglet gut health

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Journal of Animal Science and Biotechnology 2024年第2期15卷 645-658页

作者： christina Larsen Simone Margaard Offersen Anders Brunse Mattia Pirolo Soumya Kanti Kar Luca Guadabassi Thomas Thymann Department of Veterinary and Animal Science University of CopenhagenDyrlagevej 681870 Frederiksberg CDenmark Animal Nutrition Wageningen Livestock ResearchWageningen University&Research1 De Elst6708 WageningenThe Netherlands

Background Diarrhea is a major cause of reduced growth and mortality in piglets during the suckling and weaning periods and poses a major threat to the global pig industry.Diarrhea and gut dysbiosis may in part be prevented via improved early postnatal microbial colonization of the gut.To secure better postnatal gut colonization,we hypothesized that transplantation of colonic or gastric content from healthy donors to newborn recipients would prevent diarrhea in the recipients in the post-weaning period.Our objective was to examine the impact of transplanting colonic or gastric content on health and growth parameters and paraclinical parameters in recipient single-housed piglets exposed to a weaning transition and challenged with enterotoxigenic Escherichia coli(ETEC).Methods Seventy-two 1-day-old piglets were randomized to four groups:colonic microbiota transplantation(CMT,n=18),colonic content filtrate transplantation(CcFT,n=18),gastric microbiota transplantation(GMT,n=18),or saline(CON,n=18).Inoculations were given on d 2 and 3 of life,and all piglets were milk-fed until weaning(d 20)and shortly after challenged with ETEC(d 24).We assessed growth,diarrhea prevalence,ETEC concentration,organ weight,blood parameters,small intestinal morphology and histology,gut mucosal function,and microbiota composition and diversity.Results Episodes of diarrhea were seen in all groups during both the milk-and the solid-feeding phase,possibly due to stress associated with single housing.However,CcFT showed lower diarrhea prevalence on d 27,28,and 29 compared to CON(all P<0.05).CcFT also showed a lower ETEC prevalence on d 27(P<0.05).CMT showed a higher alpha diversity and a difference in beta diversity compared to CON(P<0.05).Growth and other paraclinical endpoints were similar across groups.Conclusion In conclusion,only CcFT reduced ETEC-related post-weaning diarrhea.However,the protective effect was marginal,suggesting that higher doses,more effective modalities of administration,longer treatment periods,and better donor quali

关键词： Colonic content filtrate transplantation Colonic microbiota transplantation Gastric microbiota transplantation Gut microbiota Mucosa Neonatal Post-weaning diarrhea

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Giant panda(Ailuropoda melanoleuca)neonates use broadband calls to communicate with their mothers

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Integrative Zoology 2024年第2期19卷 277-287页

作者： Lin ZHAO Jianbin CHENG Wen ZENG Bo YANG Guiquan ZHANG Desheng LI Hemin ZHANG christina DBUESCHING Dingzhen LIU Ministry of Education Key Laboratory of Biodiversity Science and Ecological EngineeringCollege of Life SciencesBeijing Normal UniversityBeijingChina Key Laboratory of State Forestry and Grassland Administration on Conservation Biology of Rare Animals in The Giant Panda National Park China Conservation and Research Center for the Giant PandaDujiangyanSichuan611830China Department of Biology Irving K.Barber Faculty of ScienceUniversity of British ColumbiaOkanaganKelownaBritish ColumbiaCanada

Infant call structure should have evolved to elicit maximum maternal attention and investment.Neonates of giant pandas produce three types of vocalizations reported to be vitally important in the context of mother–infant communications.However,how cubs,0–15 days old,communicate with their mothers to elicit maternal care remains unknown.We analyzed 12 different call parameters of 3475 squawks,1355 squalls,and 491 croaks from 11 captive giant panda(Ailuropoda melanoleuca)neonates from age 0 to 15 days.In playback experiments,we also tested whether mothers could detect ultrasound.Our results show that neonates use broadband calls with ultrasonic frequencies up to 65 kHz to convey information about their physiological needs and to attract maternal care.In playback experiments,we tested if mothers reacted differently to broadband calls(BBC)than to artificially altered calls that included only frequencies20 kHz(USC).Playback confirmed that,although adult females responded significantly less often to USC,BBC than to or AUDC,they could detect USC,BBC and generally made appropriate behavioral responses,indicating a potential benefit for neonates to utilize ultrasonic and broadband frequencies.Our findings provide a new insight into mother–infant communication in giant pandas and will be helpful for reducing the mortality of cubs,younger than 1 month old,in captivity.

关键词： acoustic communication broadband calls maternal care neonates ultrasonic frequencies

Males armed with big weapons win fights at limited cost in ant-mimickingjumping spiders

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Current Zoology 2024年第1期70卷 98-108页

作者： Guocheng Yu Boon Hui Wong christina J.Painting Hongze Li Long Yu Zengtao Zhang Shichang Zhang Daiqin Li State Key Laboratory of Biocatalysis and Enzyme Engineering and Centre for Behavioral Ecology and Evolution School of Life SciencesHubei UniversityWuhan430062China Departmentof Biological Sciences National University of Singapore14 Science Drive 4Singapore 117543Singapore Te Aka Matuatua School of Science University of WaikatoPrivate Bag 3105Hamilton 3240New Zealand

A core assumption of sexual selection theory is that sexually selected weapons,specialized morphological structures used directly in male con-tests,can improve an individual's reproductive success but only if the bearer can overcome associated costs,the negative effects on the bear-er's fitness components.However,recent studies have shown that producing and wielding exaggerated weapons may not necessarily be costly.Rather,some traits can be selected for supporting,or compensating for,the expense of producing and wielding such exaggerated weapons.n the ant-mimicking jumping spider Myrmarachne gisti,exaggerated chelicerae are borne only by adult males and not females,showing sexual dimorphism and steep positive allometry with body size.Here,we determine the potential benefits of bearing exaggerated chelicerae during male contests and explore the potential for costs in terms of prey-capture efficiency and compensation between chelicera size and neighboring trait size.While males with longer chelicerae won most of their male-male contests,we found no significant differences in prey-capture effi-ciency between males and females regardless of whether prey was winged or flightless.Males'elongated chelicerae thus do not impede their efficiency at capturing prey.Furthermore,we found that the sizes of all neighboring traits are positively correlated with chelicera size,suggesting that these traits may be under correlational selection.Taken together,our findings suggest that M.gisti males armed with the exaggerated chelicerae that function as weapons win more fights at limited cost for performance in prey capture and compensate for neighboring structures.

关键词： allometry ant-mimic costs elongated chelicerae threat devices trait compensations

Retrospective study of the incidence, risk factors, treatment outcomes of bacterial infections at uncommon sites in cirrhotic patients

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World Journal of Hepatology 2024年第3期16卷 418-427页

作者： Sophie Schneitler christina Schneider Markus Casper Frank Lammert Marcin Krawczyk Sören L Becker Matthias Christian Reichert Institute of Medical Microbiology and Hygiene Saarland UniversityHomburg 66421Germany Department of Medicine II Saarland University Medical CenterHomburg 66421Germany Health Sciences Hannover Medical SchoolHannover 30625Germany Laboratory of Metabolic Liver Diseases Department of GeneralTransplant and Liver SurgeryCentre for Preclinical ResearchMedical University of WarsawWarsaw 02-097Poland

BACKGROUND Bacterial infections(BI)negatively affect the natural course of cirrhosis.The most frequent BI are urinary tract infections(UTI),pneumonia,and spontaneousbacterial peritonitis(SBP).AIM To assess the relevance of bacterial infections beyond the commonly recognized types in patients with cirrhosis and to investigate their relationship with other clinical variables.METHODS We retrospectively analyzed patients with cirrhosis and BI treated between 2015 and 2018 at our tertiary care center.BIs were classified as typical and atypical,and clinical as well as laboratory parameters were compared between the two groups.RESULTS In a cohort of 488 patients with cirrhosis,we identified 225 typical BI(95 UTI,73 SBP,72 pulmonary infections)and 74 atypical BIs,predominantly cholangitis and soft tissue infections(21 each),followed by intra-abdominal BIs(n=9),cholecystitis(n=6),head/throat BIs(n=6),osteoarticular BIs(n=5),and endocarditis(n=3).We did not observe differences concerning age,sex,or etiology of cirrhosis in patients with typical vs atypical BI.Atypical BIs were more common in patients with more advanced cirrhosis,as evidenced by Model of End Stage Liver Disease(15.1±7.4 vs 12.9±5.1;P=0.005)and Child-Pugh scores(8.6±2.5 vs 8.0±2;P=0.05).CONCLUSION Atypical BIs in cirrhosis patients exhibit a distinct spectrum and are associated with more advanced stages of the disease.Hence,the work-up of cirrhosis patients with suspected BI requires detailed work-up to elucidate whether typical BI can be identified.

关键词： Bacterial infection Empirical antibiotic therapy End-stage liver disease Escherichia coli Multi-resistant pathogens

Sol-gel derived B_(2)O_(3)-CaO borate bioactive glasses with hemostatic,antibacterial and pro-angiogenic activities

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Regenerative Biomaterials 2024年第1期3卷 108-118页

作者： Kai Zheng Faina Bider Mahshid Monavari Zhiyan Xu christina Janko Christoph Alexiou Ana M.Beltran Aldo R.Boccaccini Jiangsu Province Engineering Research Center of Stomatological Translational Medicine College of StomatologyNanjing Medical UniversityNanjing 210029China Jiangsu Key Laboratory of Oral Diseases Nanjing Medical UniversityNanjing 210029China Institute of Biomaterials University of Erlangen-Nuremberg91058 ErlangenGermany Department of Oto-Rhino-Laryngology Head and Neck SurgerySection of Experimental Oncology and Nanomedicine(SEON)Else Kroener-Fresenius-Stiftung ProfessorshipUniversitaetsklinikum Erlangen91058 ErlangenGermany Departamento de Ingenier�ıa y Ciencia de los Materiales y del Transporte Escuela Politecnica

Sol-gel borate bioactive glasses(BGs)are promising ion-releasing biomaterials for wound healing applications.Here,we report the synthesis of a series of binary B_(2)O_(3)-CaO borate BGs(CaO ranging from 50 to 90mol%)using a sol-gel-based method.The influence of CaO content in B_(2)O_(3)-CaO borate BG on morphology,structure and ion release behavior was investigated in detail.Reduced dissolution(ion release)and crystallization could be observed in borate BGs when CaO content increased,while the morphology was not significantly altered by increasing CaO content.Our results evidenced that the ion release behavior of borate BGs could be tailored by tuning the B_(2)O_(3)/CaO molar ratio.We also evaluated the in vitro cytotoxicity,hemostatic,antibacterial and angiogenic activities of borate BGs.Cytocompatibility was validated for all borate BGs.However,borate BGs exhibited composition-dependent hemostatic,antibacterial and angiogenic activities.Generally,higher contents of Ca in borate BGs facilitated hemostatic activity,while higher contents of B_(2)O_(3) were beneficial for pro-angiogenic activity.The synthesized sol-gel-derived borate BGs are promising materials for developing advanced wound healing dressings,given their fast ion release behavior and favorable hemostatic,antibacterial and angiogenic activities.

关键词： borate glasses sol-gel processing glass composition wound healing

Design,Synthesis,and Applications of Mesoporous Covalent Organic Frameworks

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CCS Chemistry 2024年第1期6卷 57-68页

作者： Niyati Arora Cassandra Flores Milinda C.Senarathna christina M.Thompson Ronald A.Smaldone Department of Chemistry and Biochemistry University of TexasDallasRichardsonTexas 75080

Covalent organic frameworks(COFs)are highly ordered and permanently porous organic polymers that can be classified as two-dimensional or threedimensional.Their tunable design and crystalline order endow a range of pore sizes,shapes,functions,and applications that differentiate them from other polymers.The COF pore sizes and shapes rely on the geometry of the monomers and dynamic covalent chemistry,while the stacking of the sheets relies on noncovalent interactions.Their tunability allows for post-modification or the incorporation of additional functional groups for the reinforcement by various noncovalent interactions.The limits of mesoporous COFs are still being investigated,with the design rules continuing to evolve.Here we report a comprehensive review of mesoporous COFs,explore strategies for large pore reinforcement,highlight structural design and features,elucidate their various functions and applications,discuss fundamental challenges faced that need to be addressed,and predict future directions.

关键词： covalent organic frameworks mesoporous supramolecular chemistry polymers pore size

The effect of high-flow oxygen via tracheostomy on respiratory pattern and diaphragmatic function in patients with prolonged mechanical ventilation:A randomized,physiological,crossover study

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Journal of Intensive Medicine 2024年第2期4卷 202-208页

作者： Elena Lytra Stelios Kokkoris Ioannis Poularas Dimitrios Filippiadis Demosthenes Cokkinos Dimitrios Exarhos Spyros Zakynthinos christina Routsi 1st Department of Intensive Care Medical SchoolNational and Kapodistrian University of AthensEvangelismos HospitalAthensGreece Radiology Department Evangelismos HospitalAthensGreece 2nd Radiology Department Medical SchoolNational and Kapodistrian University of AthensAttikon HospitalAthensGreece

Background Compared to conventional oxygen devices,high-flow oxygen treatment(HFOT)through the nasal cannulae has demonstrated clinical benefits.Limited data exist on whether such effects are also present in HFOT through tracheostomy.Hence,we aimed to examine the short-term effects of HFOT through tracheostomy on diaphragmatic function and respiratory parameters in tracheostomized patients on prolonged mechanical ventilation.Methods A randomized,crossover,physiological study was conducted in our ICU between December 2020 and April 2021,in patients with tracheostomy and prolonged mechanical ventilation.The patients underwent a 30-min spontaneous breathing trial(SBT)and received oxygen either via T-piece or by HFOT through tracheostomy,followed by a washout period of 15-min breathing through the T-piece and receipt of 30-min oxygen with the other modality in a randomized crossover manner.At the start and end of each session,blood gasses,breathing frequency(f),and tidal volume(VT)via a Wright's spirometer were measured,along with diaphragm ultrasonography including diaphragm excursion and diaphragmatic thickening fraction,which expressed the inspiratory muscle effort.Results Eleven patients were enrolled in whom 19 sessions were uneventfully completed;eight patients were studied twice on two different days with alternate sessions;and three patients were studied once.Patients were randomly assigned to start the SBT with a T-piece(n=10 sessions)or with HFOT(n=9 sessions).With HFOT,VT and minute ventilation(VE)significantly increased during SBT(from[465±119]mL to[549±134]mL,P<0.001 and from[12.4±4.3]L/min to[13.1±4.2]L/min,P<0.05,respectively),but they did not change significantly during SBT with T-piece(from[495±132]mL to[461±123]mL and from[12.8±4.4]mL to[12.0±4.4]mL,respectively);f/VT decreased during HFOT(from[64±31]breaths/(min∙L)to[49±24]breaths/(min∙L),P<0.001),but it did not change significantly during SBT with T-piece(from[59±28]breaths/(min∙L)to[64±33]breaths/(min∙L));partial pressure of arterial oxygen incre

关键词： Diaphragm Diaphragm ultrasonography High-flow 0Xygen Prolonged mechanical ventilation Tracheostomy