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A high-order target phase approach for the station-keeping of periodic orbits

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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu Fu Nicola Baresi roberto Armellin Surrey Space Centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland Space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this work.The key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA parameters.Quasi-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical models.Monte Carlo simulations demonstrated that the baseline QSO of JAXA’s Martian Moons eXploration(MMX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

A high aspect ratio surface micromachined accelerometer based on a SiC-CNT composite material

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Microsystems & Nanoengineering 2024年第2期10卷 219-230页

作者： Jiarui Mo Shreyas Shankar roberto Pezone Guoqi Zhang Sten Vollebregt Laboratory of Electronic Components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands

Silicon carbide(SiC)is recognized as an excellent material for microelectromechanical systems(MEMS),especially those operating in challenging environments,such as high temperature,high radiation,and corrosive environments.However,SiC bulk micromachining is still a challenge,which hinders the development of complex SiC MEMS.To address this problem,we present the use of a carbon nanotube(CNT)array coated with amorphous SiC(a-SiC)as an alternative composite material to enable high aspect ratio(HAR)surface micromachining.By using a prepatterned catalyst layer,a HAR CNT array can be grown as a structural template and then densified by uniformly filling the CNT bundle with LPCVD a-SiC.The electrical properties of the resulting SiC-CNT composite were characterized,and the results indicated that the electrical resistivity was dominated by the CNTs.To demonstrate the use of this composite in MEMS applications,a capacitive accelerometer was designed,fabricated,and measured.The fabrication results showed that the composite is fully compatible with the manufacturing of surface micromachining devices.The Young’s modulus of the composite was extracted from the measured spring constant,and the results show a great improvement in the mechanical properties of the CNTs after coating with a-SiC.The accelerometer was electrically characterized,and its functionality was confirmed using a mechanical shaker.

关键词： composite surface electrical

The effect of abiotic stresses on plant C:N:P homeostasis and their mitigation by silicon

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The Crop Journal 2024年第2期12卷 340-353页

作者： Milton Garcia Costa Renato de Mello prado Luiz Fabiano Palaretti Jonas Pereira de Souza Júnior Department of Agricultural Production Science School of Agricultural and Veterinarian SciencesSão Paulo State UniversityJaboticabalBrazil

In crop plants, various environmental stresses affect the balance of carbon, nitrogen, and phosphorus(C:N:P), leading to biochemical and physiological alterations and reductions in yield. Silicon(Si) is a beneficial element that alleviates plant stress. Most studies involving silicon have focused on physiological responses, such as improvements in photosynthetic processes, water use efficiency, and antioxidant defense systems. But recent research suggests that stressed plants facing either limited or excessive resources(water, light, nutrients, and toxic elements), strategically employ Si to maintain C:N:P homeostasis, thereby minimizing biomass losses. Understanding the role of Si in mitigating the impact of abiotic stresses on plants by regulating C:N:P homeostasis holds great potential for advancing sustainable agricultural practices in crop production. This review presents recent advances in characterizing the influence of environmental stresses on C:N:P homeostasis, as well as the role of Si in preserving C:N:P equilibrium and attenuating biological damage associated with abiotic stress. It underscores the beneficial effects of Si in sustaining C:N:P homeostasis and increasing yield via improved nutritional efficiency and stress mitigation.

关键词： Nutritional stoichiometry Elemental stoichiometry Beneficial element Environmental stresses Nutritional efficiency Carbon use efficiency Agricultural sustainability

Interleukin 1βreceptor and synaptic dysfunction in recurrent brain infection with Herpes simplex virus type-1

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Neural Regeneration Research 2025年第2期20卷 416-423页

作者： roberto Piacentini Claudio Grassi Department of Neuroscience UniversitàCattolica del Sacro CuoreRomeItaly Fondazione Policlinico Universitario A.Gemelli IRCCSRomeItaly

Several experimental evidence suggests a link between brain Herpes simplex virus type-1 infection and the occurrence of Alzheimer’s disease.However,the molecular mechanisms underlying this association are not completely understood.Among the molecular mediators of synaptic and cognitive dysfunction occurring after Herpes simplex virus type-1 infection and reactivation in the brain neuroinflammatory cytokines seem to occupy a central role.Here,we specifically reviewed literature reports dealing with the impact of neuroinflammation on synaptic dysfunction observed after recurrent Herpes simplex virus type-1 reactivation in the brain,highlighting the role of interleukins and,in particular,interleukin 1βas a possible target against Herpes simplex virus type-1-induced neuronal dysfunctions.

关键词： herpes simplex virus type 1 interleukin 1β microglia neuroinflammation synaptic dysfunction

Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： Esteban Diaz Edgar Leonardo Salamanca-Medina roberto Tomas Departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction projects.The high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test fields.The present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research papers.The selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive strength.Despite the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing works.Consequently,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

Double-nylon purse-string suture technique: Another addition to the endoscopist's toolbox for full-thickness defect closure

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World Journal of Gastroenterology 2024年第25期30卷 3152-3154页

作者： Angad Walia roberto Paolo Trasolini Neal Shahidi Department of Medicine University of British ColumbiaVancouver V6Z2K5BCCanada

Iatrogenic perforation is the most feared adverse event in endoscopy.With the expansion of interventional endoscopy in favor of traditional surgery,it is now more crucial than ever to develop effective defect closure techniques.This has culminated in the dissemination of multiple novel closure technologies,including through-the-scope clips,over-the-scope clips,through-the-scope suturing and over-the-scope suturing devices.In this editorial,we comment on the recent publication by Wang and colleagues discussing the performance of the double-nylon purse-string suture technique in the closure of large(>3 cm)gastric full-thickness defects.This technique offers a promising,practical and cost-effective approach to closure of large full-thickness defects that can be readily imple-mented across diverse healthcare settings.

关键词： Cancer Endoscopy Endoscopic full-thickness resection Perforation

Effect of resistance training volume on body adiposity,metabolic risk,and inflammation in postmenopausal and older females:Systematic review and meta-analysis of randomized controlled trials

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Journal of Sport and Health Science 2024年第2期13卷 145-159页

作者： Paulo Ricardo prado Nunes Pamela Castro-e-Souza Anselmo Alves de Oliveira Bruno de Freitas Camilo Gislaine Cristina-Souza Lucio Marques Vieira-Souza Marcelo Augusto da Silva Carneiro Department of Body and Human Movement Minas Gerais State University(UEMG)37902-092 PassosMGBrazil University Center of Planalto de Araxa(UNIARAXA) 38180-129 AraxaMGBrazil Physical Activity Health and Ageing Research Group(GPASE)Minas Gerais State University(UEMG)37902-092 PassosMGBrazil Exercise and Nutrition Research Group(GPEN) Minas Gerais State University(UEMG)37902-092 PassosMGBrazil Sport Sciences and Physical Exercise Study and Research Group(GEPCEEX) Minas Gerais State University(UEMG)37902-092 PassosMGBrazil Metabolism Nutrition and Exercise LaboratoryPhysical Education and Sport CenterLondrina State University(UEL)86050-070 LondrinaPRBrazil Postgraduate Program in Physical Education Federal University of Sergipe(UFS)49107-230 Sao CristovaoSEBrazil

Purpose:This meta-analytical study aimed to explore the effects of resistance training(RT) volume on body adiposity,metabolic risk,and inflammation in postmenopausal and older females.Methods:A systematic search was performed for randomized controlled trials in PubMed,Scopus,Web of Science,and SciELO.Randomized controlled trials with postmenopausal and older females that compared RT effects on body adiposity,metabolic risk,and inflammation with a control group(CG) were included.Independent reviewers selected the studies,extracted the data,and performed the risk of bias and certainty of the evidence(Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)) evaluations.Total body and abdominal adiposity,blood lipids,glucose,and C-reactive protein were included for meta-analysis.A random-effects model,standardized mean difference(Hedges’ g),and 95% confidence interval(95%CI) were used for meta-analysis.Results:Twenty randomized controlled trials(overall risk of bias:some concerns;GRADE:low to very low) with overweight/obese postmenopausal and older females were included.RT groups were divided into low-volume RT(LVRT,~44 sets/week) and high-volume RT(HVRT,~77 sets/week).Both RT groups presented improved body adiposity,metabolic risk,and inflammation when compared to CG.However,HVRT demonstrated higher effect sizes than LVRT for glucose(HVRT=-1.19;95%CI:-1.63 to-0.74;LVRT=-0.78;95%CI:-1.15 to-0.41) and C-reactive protein(HVRT=-1.00;95%CI:-1.32 to-0.67;LVRT=-0.34;95%CI,-0.63 to-0.04)) when compared to CG.Conclusion:Compared to CG,HVRT protocols elicit greater improvements in metabolic risk and inflammation outcomes than LVRT in overweight/obese postmenopausal and older females.

关键词： C-reactive protein Fat mass Lipid profile Menopause Strength training

Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones

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Microsystems & Nanoengineering 2024年第1期10卷 267-275页

作者： roberto Pezone Sebastian Anzinger Gabriele Baglioni Hutomo Suryo Wasisto Pasqualina M.Sarro Peter G.Steeneken Sten Vollebregt Laboratory of Electronic Components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands Infineon Technologies AG Am Campeon 1-15Neubiberg 85579Germany Kavli Institue of Nanoscience Department of Quantum NanoscienceDelft University of TechnologyDelftthe Netherlands Department of Precision and Microsystems Engineering(PME) Delft University of TechnologyDelftThe Netherlands

Since the performance of micro-electro-mechanical system(MEMS)-based microphones is approaching fundamental physical,design,and material limits,it has become challenging to improve them.Several works have demonstrated graphene’s suitability as a microphone diaphragm.The potential for achieving smaller,more sensitive,and scalable onchip MEMS microphones is yet to be determined.To address large graphene sizes,graphene-polymer heterostructures have been proposed,but they compromise performance due to added polymer mass and stiffness.This work demonstrates the first wafer-scale integrated MEMS condenser microphones with diameters of 2R=220-320μm,thickness of 7 nm multi-layer graphene,that is suspended over a back-plate with a residual gap of 5μm.The microphones are manufactured with MEMS compatible wafer-scale technologies without any transfer steps or polymer layers that are more prone to contaminate and wrinkle the graphene.Different designs,all electrically integrated are fabricated and characterized allowing us to study the effects of the introduction of a back-plate for capacitive read-out.The devices show high mechanical compliances C_(m)=0.081-1.07μmPa^(−1)(10-100×higher than the silicon reported in the state-of-the-art diaphragms)and pull-in voltages in the range of 2-9.5 V.In addition,to validate the proof of concept,we have electrically characterized the graphene microphone when subjected to sound actuation.An estimated sensitivity of S_(1kHz)=24.3-321 mV Pa^(−1)for a V_(bias)=1.5 V was determined,which is 1.9-25.5×higher than of state-of-the-art microphone devices while having a~9×smaller area.

关键词： transfer plate approaching

Nutrient restriction-activated Fra-2 promotes tumor progression via IGF1R in miR-15a downmodulated pancreatic ductal adenocarcinoma

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1132-1146页

作者： Gian Luca Rampioni Vinciguerra Marina Capece Luca Reggiani Bonetti Giovanni Nigita Federica Calore Sydney Rentsch Paolo Magistri roberto Ballarin Fabrizio Di Benedetto Rosario Distefano roberto Cirombella Andrea Vecchione Barbara Belletti Gustavo Baldassarre Francesca Lovat Carlo M.Croce Department of Cancer Biology and Genetics and Comprehensive Cancer Center The Ohio State UniversityColumbus 43210 OHUSA Department of Clinical and Molecular Medicine Faculty of Medicine and PsychologySant’Andrea HospitalUniversity of Rome“Sapienza”Rome 00189Italy Department of Diagnostic Clinic and Public Health MedicineUniversity of Modena and Reggio EmiliaModena 41100Italy Hepato-pancreato-biliary Surgery and Liver Transplantation Unit University of Modena and Reggio EmiliaModena 41100Italy Division of Molecular Oncology Centro di Riferimento Oncologico di Aviano(CRO)Istituto di Ricovero e Cura a Carattere Scientifico(IRCCS)National Cancer InstituteAviano 33081Italy

Pancreatic ductal adenocarcinoma(PDAC)is a lethal disease,characterized by an intense desmoplastic reaction that compresses blood vessels and limits nutrient supplies.PDAC aggressiveness largely relies on its extraordinary capability to thrive and progress in a challenging tumor microenvironment.Dysregulation of the onco-suppressor miR-15a has been extensively documented in PDAC.Here,we identified the transcription factor Fos-related antigen-2(Fra-2)as a miR-15a target mediating the adaptive mechanism of PDAC to nutrient deprivation.We report that the IGF1 signaling pathway was enhanced in nutrient deprived PDAC cells and that Fra-2 and IGF1R were significantly overexpressed in miR-15a downmodulated PDAC patients.Mechanistically,we discovered that miR-15a repressed IGF1R expression via Fra-2 targeting.In miR-15a-low context,IGF1R hyperactivated mTOR,modulated the autophagic flux and sustained PDAC growth in nutrient deprivation.In a genetic mouse model,Mir15aKO PDAC showed Fra-2 and Igf1r upregulation and mTOR activation in response to diet restriction.Consistently,nutrient restriction improved the efficacy of IGF1R inhibition in a Fra-2 dependent manner.Overall,our results point to a crucial role of Fra-2 in the cellular stress response due to nutrient restriction typical of pancreatic cancer and support IGF1R as a promising and vulnerable target in miR-15a downmodulated PDAC.

关键词： IGF1R Fra miR