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黏声波方程波场模拟的通用格式自适应系数频域有限差分方法

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地球物理学报 2024年第2期67卷 654-669页

作者：徐文豪巴晶 j.m.Carcione 朱鹤松河海大学地球科学与工程学院南京211100 National Institute of Oceanography and Applied Geophysics-OGS Borgo Grotta Gigante 42/cTriesteSgonico 34010Italy

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency domain,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格... 详细信息

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency domain,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格点数小于4时误差较大.通过令FDFD系数随一个波长内的网格点数自适应从而提高FDFD方法的精度,本文针对黏声波波场模拟发展了一种适用于不同空间采样间隔之比的通用格式自适应系数FDFD方法.同时,为了验证自适应系数FDFD方法对一般黏声波模型的有效性,本文针对三个典型的黏声波模型,分别采用解析解和基于高阶FDFD的参考解验证了所提出方法的有效性.本方法的FDFD格式通过在传统的二阶FDFD格式的基础上引入相关校正项得到,其中校正项按网格点与中心点的距离进行分类选取,同时校正项对应的自适应FDFD系数不仅和空间采样间隔之比相关,还和一个波长内的采样点数相关.所需的自适应FDFD系数可通过声波方程的数值频散关系和查找表高效给出.数值频散分析表明,在空间采样间隔相等或不等的情况下,以相速度误差不超过1%为标准,通用格式自适应系数FDFD方法所需的一个波长内的采样点数均小于2.5.数值模拟实验表明,对于不同的空间采样间隔之比,相对于常用的二阶五点FDFD方法和优化九点FDFD方法,通用格式自适应系数FDFD方法均可在相似的计算量和内存需求下,有效提高黏声波模拟的精度.

关键词：黏声波频域有限差分自适应系数波场模拟通用格式

Design and synthesis of synthetic promoters for consistency of gene expression across growth phases and scale in ***

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Synthetic and Systems Biotechnology 2024年第2期9卷 330-339页

作者： Kristin V.Presnell Omar melhem Sarah m.Coleman Nicholas j.morse Hal S.Alper mcKetta Department of Chemical Engineering The University of Texas at Austin200E Dean Keeton St.Stop C0400AustinTX78712USA Institute for Cellular and molecular Biology The University of Texas at Austin2500 Speedway AvenueAustinTX78712USA

metabolic engineering and synthetic biology endeavors benefit from promoters that perform consistently(or robustly)with respect to cellular growth phase(exponential and stationary)and fermentation scale(microtiter plates,tubes,flasks,and bioreactors).However,nearly all endogenous promoters(especially in Saccharomyces cerevisiae)do not perform in this *** this work,a hybrid promoter engineering strategy is leveraged to create novel synthetic promoters with robustness across these *** a multi-dimensional RNA-seq dataset,promoters with specific phase dependencies were *** enriched with functional transcription factors were identified using mEmE *** motif-containing fragments could impart activity dependence in the opposing ***,we obtain two new promoters with high and consistent expression across both phases by increasing the exponential phase activity of the starting stationary-phase scaffold by 38 and 23-fold ***,we show that these promoters function consistently across various laboratory growth scales over time in a microtiter plate and in ***,this work presents and validates a new strategy for engineering promoters in *** with high levels of expression that are robust to cellular growth phase and the scale of the culture.

关键词： endogenous synthetic stationary

Experimental test of a building thermal system for preventive maintenance based on thermoeconomic analysis

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Energy Storage and Saving 2024年第1期3卷 42-51页

作者： I.Prol-Godoy A.Picallo-Perez j.m.Sala-Lizarraga j.Rey-martínez Research group ENEDI Department of Thermal EngineeringUniversity of the Basque Country(UPV/EHU)Bilbao48013Spain Research Group Termotecnia University of ValladolidValladolid47002Spain

An analysis of the sectorial structure of energy consumption shows that residential and tertiary sector buildings are the third-highest consumers,responsible for 29.5%of a city’s final energy *** Building Quality Control Laboratory of the Basque Government aims to promote quality,innovation,and sustainability in *** accomplish this goal,it has constructed an experimental facility with different energy generation technologies and a very versatile control system for testing different energy systems and operation *** this study,we tested a facility for supplying domestic hot water and heating for a multi-family house by means of a condensing boiler and an aerothermal heat pump(together with the corresponding control).This installation could reproduce the thermal demands required to be satisfied by the generation equipment through a programmed operation of the installation based on real ***,this installation was analyzed using thermoeconomics(TE)to solve problems unable to be solved using traditional energy analyses based on the First Law of *** problems include:(1)Determining the costs of the products of the installation based on physical criteria,(2)detecting the places where losses actually occur,evaluating their costs,and proposing cost-effective improvements,and(3)diagnosing issues in the *** a result,this paper suggests a solution to the preventive maintenance problems confronting the technical maintenance personnel for thermal installations in buildings by applying TE knowledge and using real data collected from sensors.

关键词： Experimental essay Energy savings in thermal systems Thermoeconomics Thermoeconomic costs Diagnosis

morphological traits explain the individual position within resource-consumer networks of a Neotropical marsupial

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Current Zoology 2024年第4期70卷 453-464页

作者： Nicholas F.de Camargo Hernani F.m.de Oliveira juliana F.Ribeiro Amabilio j.A.de Camargo Emerson m.Vieira Laboratorio de Ecologia de Vertebrados Departamento de EcologiaInstituto de Ciencias BiologicasUniversidade de BrasiliaCP 04457BrasiliaDF70910-900Brazil Departamento de Zoologia Setor de Ciencias BiologicasUniversidade Federal do ParanaAvenida Coronel Francisco Heraclito dos Santos100CuritibaPR81531980Brazil Embrapa Cerrados Rodovia BR020km 18CP 08223PlanaltinaDE73310-970Brazil

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation *** tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian *** with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet *** relationship between individuals'position in the network and body traits,however,was independent of *** propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological ***/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more ***,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.

关键词： bodytraits centrality Cerrado Gracilinanus agilis seasonality specialization.

Nutritional epigenetics education improves diet and attitude of parents of children with autism or attention deficit/hyperactivity disorder

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World journal of Psychiatry 2024年第1期14卷 159-178页

作者： Renee j Dufault Katherine m Adler David O Carpenter Steven G Gilbert Raquel A Crider College of Graduate Health Studies A.T.Still UniversityKirksvilleMO 63501United States Department of Research Food Ingredient and Health Research InstituteNaalehuHI 96772United States Department of Health Sciences University of New HavenWest HavenCT 06516United States Institute for Health and the Environment School of Public HealthState University of New YorkAlbanyNY 12222United States Department of Research Institute of Neurotoxicology and Neurological DisordersSeattleWA 98105United States Department of Statistics Food Ingredient and Health Research InstituteNaalehuHI 96772United States

BACKGROUND Unhealthy maternal diet leads to heavy metal exposures from the consumption of ultra-processed foods that may impact gene behavior across generations,creating conditions for the neurodevelopmental disorders known as autism and attention deficit/hyperactivity disorder(ADHD).Children with these disorders have difficulty metabolizing and excreting heavy metals from their bloodstream,and the severity of their symptoms correlates with the heavy metal levels measured in their *** may play a key role in helping parents reduce their ultra-processed food and dietary heavy metal intake by providing access to effective nutritional epigenetics *** To test the efficacy of nutritional epigenetics instruction in reducing parental ultra-processed food *** The study utilized a semi-randomized test and control group pretest-posttest pilot study design with participants recruited from parents having a learning-disabled child with autism or ***-two parents who met the inclusion criteria were randomly selected to serve in the test(n=11)or control(n=11)*** test group participated in the six-week online nutritional epigenetics tutorial,while the control group did *** efficacy of the nutritional epigenetics instruction was determined by measuring changes in parent diet and attitude using data derived from an online diet survey administered to the participants during the pre and post intervention *** intake scores were derived for both ultra-processed and whole/organic *** sample t-tests were conducted to determine any differences in mean diet scores within each *** There was a significant difference in the diet scores of the test group between the pre-and post-intervention *** parents in the test group significantly reduced their intake of ultra-processed foods with a preintervention diet score of 70(mean=5.385,SD=2.534)and a post-intervention diet score of 113(mean=8.692,SD=1.750)and the

关键词： Epigenomics Parenteral nutrition Autism Attention deficit/hyperactivity disorder Ultra-processed foods Heavy metals

The CCD instrument background of the SmILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： m.W.j.Hubbard O.Hetherington D.j.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SmILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

CONSTANS alters the circadian clock in Arabidopsis thaliana

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molecular Plant 2024年第8期17卷 1204-1220页

作者： Pedro de los Reyes Gloria Serrano-Bueno Francisco j.Romero-Campero He Gao jose m.Romero Federico Valverde Plant Development Group-Institute for Plant Biochemistry and Photosynthesis Consejo Superior de Investigaciones CientificasUniversidad de SevillaSevilleSpain Department of Computer Science and Artificial Intelligence Universidad de SevillaSevilleSpain Department of Plant Developmental Biology Max Planck Institute for Plant Breeding ResearchCologneGermany Department of Plant Biochemistry and molecular Biology Universidad de SevillaSevilleSpain

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the *** these processes,the floral transition is essential to ensure reproductive success and is finelyregulated by several internal andexternal genetic *** photoperiodic pathway,which controls plant response to day length,is one of the most important pathways controlling *** Arabidopsis photoperiodic flowering,CONSTANS(CO)is the central gene activating the expression of the florigen FLOWERING LOCUS T(FT)in the leaves at the end of a long *** circadian clock strongly regulates Co ***,to date,no evidence has been reported regarding a feedbackloop from the photoperiod pathway back to the circadian *** transcriptional networks,we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod *** expression,chromatin immunoprecipitation experiments,and phenotypic analysis allowed us to elucidate the role of Co over the circadian *** with altered cO expression showed a different internal clock period,measured by daily leaf rhythmic *** showed that co upregulates the expression of key genes related to the circadian clock,such as CCA1,LHY,PRR5,and Gl,at the end of a long day by bindingto specific sites on their ***,a high numberof PRR5-repressed target genes are upregulated by CO,and this could explain the phase transition promoted by *** CO-PRR5 complex interacts with the bZiP transcriptionfactor HY5andhelps to localize the complex in the promoters of clock *** together,our results indicate that there may be a feedback loop in which co communicates back to the circadian clock,providing seasonal information to the circadian system.

关键词： CONSTANS circadian clock photoperiod

Telomeric DNA breaks in human induced pluripotent stem cells trigger ATR-mediated arrest and telomerase-independent telomere damage repair

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journal of molecular Cell Biology 2024年第3期16卷 46-60页

作者： Katrina N.Estep john W.Tobias Rafael j.Fernandez Brinley m.Beveridge F.Brad johnson Department of Pathology and Laboratory medicine University of PennsylvaniaPhiladelphiaPA 19104USA Quantiative Biosciences Merck&Co.Inc.West PointPA 19486USA Penn Genomic Analysis Core University of PennsylvaniaPhiladelphiaPA 19104USA

Although mechanisms of telomere protection are well-defined in differentiated cells,how stem cells sense and respond to telomere dysfunction,in particular telomeric double-strand breaks(DSBs),is poorly ***,we report the DNA damage signaling,cell cycle,and transcriptome changes in human induced pluripotent stem cells(iPSCs)in response to telomere-internal *** engineer human iPSCs with an inducible TRF1-FokI fusion protein to acutely induce DSBs at *** this model,we demonstrate that TRF1-FokI DSBs activate an ATR-dependent DNA damage response,which leads to p53-independent cell cycle arrest in *** CRISPR–Cas9 to cripple the catalytic domain of telomerase reverse transcriptase,we show that telomerase is largely dispensable for survival and lengthening of TRF1-FokI-cleaved telomeres,which instead are effectively repaired by robust homologous recombination(HR).In contrast to HR-based telomere maintenance in mouse embryonic stem cells,where HR causes ZSCAN4-dependent extension of telomeres beyond their initial lengths,HR-based repair of telomeric breaks is sufficient to maintain iPSC telomeres at a normal length,which is compatible with sustained survival of the cells over several days of TRF1-FokI *** findings suggest a previously unappreciated role for HR in telomere maintenance in telomerase-positive iPSCs and reveal distinct iPSC-specific responses to targeted telomeric DNA damage.

关键词： telomeres telomerase alternative lengthening of telomeres pluripotent stem cells DNA damage double-strand breaks

In vivo measurement of NADH fluorescence lifetime in skeletal muscle via -ber-coupled time-correlated single photon counting

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journal of Innovative Optical Health Sciences 2024年第1期17卷 121-134页

作者： Kathryn m.Priest jacob V.Schluns Nathania Nischal Colton L.Gattis jeffrey C.Wolchok Timothy j.muldoon Department of Biomedical Engineering University of Arkansas FayettevilleARUSA

Nicotinamide adenine dinucleotide(NADH)is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis,the tricarboxylic acid cycle,and oxidative phosphorylation(OXPHOS).NADH is autofluorescent,and itsfluorescence lifetime can be used to infer metabolic dynamics in living ***-coupled time-correlated single photon counting(TCSPC)equipped with an implantable needle probe can be used to measure NADH lifetime in vivo,enabling investigation of changing metabolic demand during muscle contraction or tissue *** study illustrates a proof of concept for point-based,minimally-invasive NADHfluorescence lifetime measurement in *** muscle loss(VmL)injuries were created in the left tibialis anterior(TA)muscle of male Sprague Dawley *** lifetime measurements were collected before,during,and after a 30 s tetanic contraction in the injured and uninjured TA muscles,which was subsequently-t to a biexponential decay model to yield a metric of NADH utilization(cytoplasmic vs protein-bound NADH,the A11/A22 ratio).On average,this ratio was higher during and after contraction in uninjured muscle compared to muscle at rest,suggesting higher levels of free NADH in contracting and recovering muscle,indicating increased rates of *** injured muscle,this ratio was higher than uninjured muscle overall but decreased over time,which is consistent with current knowledge of inflammatory response to injury,suggesting tissue regeneration has *** data suggest that-ber-coupled TCSPC has the potential to measure changes in NADH binding in vivo in a minimally invasive manner that requires further investigation.

关键词： Glycolysis oxidative phosphorylation energy metabolism volumetric muscle loss