基于蒙特卡罗模拟的透射式XRD背景的定量分析

XRD背景主要来源于空气、装置和样品中光子的散射,XRD分析需准确扣除背景,常用的扣背景方法具有一定的局限。蒙特卡罗模拟可实现光子的甄别与统计,因此可将其用于XRD背景来源的定量分析。相干散射的模拟中需考虑物质的Form Factor,这可由Baró等的拟合式、独立原子模型或德拜公式给出;在20 keV能量及透射几何模式下,通过对骨、尼龙、水等物质的XRD模拟,对探测器中光子来源进行了区分和统计。结果表明,德拜公式计算的空气背景大于独立原子模型;空气散射在小角度时背景占比大,随散射角的增加从100%减小至40%以下,而样品中康普顿散射的计数占比则从0增大至60%以上。该方法可对不同样品组成以及复杂装置结构的XRD背景进行定量分析。

Sorl1 knockout inhibits expression of brain-derived neurotrophic factor:involvement in the development of late-onset Alzheimer's disease

Sortilin-related receptor 1(SORL1)is a critical gene associated with late-onset Alzheimer’s disease.SORL1 contributes to the development and progression of this neurodegenerative condition by affecting the transport and metabolism of intracellularβ-amyloid precursor protein.To better understand the underlying mechanisms of SORL1 in the pathogenesis of late-onset Alzheimer s disease,in this study,we established a mouse model of SorI1 gene knockout using cluste red regularly inters paced short palindro mic repeats-associated protein 9 technology.We found that Sorl1-knocko ut mice displayed deficits in learning and memory.Furthermore,the expression of brain-derived neurotrophic factor was significantly downregulated in the hippocampus and co rtex,and amyloidβ-protein deposits were observed in the brains of 5orl1-knockout mice.In vitro,hippocampal neuronal cell synapses from homozygous Sorl1-knockout mice were impaired.The expression of synaptic proteins,including Drebrin and NR2B,was significantly reduced,and also their colocalization.Additionally,by knocking out the Sorl1 gene in N2a cells,we found that expression of the N-methyl-D-aspartate receptor,NR2B,and cyclic adenosine monophosphate-response element binding protein was also inhibited.These findings suggest that SORL1 participates in the pathogenesis of late-onset Alzheimer s disease by regulating the N-methyl-D-aspartate receptor NR2B/cyclic adenosine monophosphate-response element binding protein signaling axis.

Adult neurogenesis:a real hope or a delusion?

Adult neurogenesis,the process of creating new neurons,involves the coordinated division,migration,and differentiation of neural stem cells.This process is restricted to neurogenic niches located in two distinct areas of the brain:the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle,where new neurons are generated and then migrate to the olfactory bulb.Neurogenesis has been thought to occur only during the embryonic and early postnatal stages and to decline with age due to a continuous depletion of neural stem cells.Interestingly,recent years have seen tremendous progress in our understanding of adult brain neurogenesis,bridging the knowledge gap between embryonic and adult neurogenesis.Here,we discuss the current status of adult brain neurogenesis in light of what we know about neural stem cells.In this notion,we talk about the importance of intra cellular signaling molecules in mobilizing endogenous neural stem cell prolife ration.Based on the current understanding,we can declare that these molecules play a role in targeting neurogenesis in the mature brain.However,to achieve this goal,we need to avoid the undesired proliferation of neural stem cells by controlling the necessary checkpoints,which can lead to tumorigenesis and prove to be a curse instead of a blessing or hope.

Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning

BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective preventive measures.AIM To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and treatment.METHODS Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU admission.Relevant data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were gathered.The relationships between these variables and ICU-AW were examined.Utilizing iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic curve.RESULTS Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW group.Additionally,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical significance.The most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechanical ventilation duration.

Speed and surface steepness affect internal tibial loading during running

Background:Internal tibial loading is influenced by modifiable factors with implications for the risk of stress injury.Runners encounter varied surface steepness(gradients)when running outdoors and may adapt their speed according to the gradient.This study aimed to quantify tibial bending moments and stress at the anterior and posterior peripheries when running at different speeds on surfaces of different gradients.Methods:Twenty recreational runners ran on a treadmill at 3 different speeds(2.5 m/s,3.0 m/s,and 3.5 m/s)and gradients(level:0%;uphill:+5%,+10%,and+15%;downhill:-5%,-10%,and-15%).Force and marker data were collected synchronously throughout.Bending moments were estimated at the distal third centroid of the tibia about the medial-lateral axis by ensuring static equilibrium at each 1%of stance.Stress was derived from bending moments at the anterior and posterior peripheries by modeling the tibia as a hollow ellipse.Two-way repeated-measures analysis of variance were conducted using both functional and discrete statistical analyses.Results:There were significant main effects for running speed and gradient on peak bending moments and peak anterior and posterior stress.Higher running speeds resulted in greater tibial loading.Running uphill at+10%and+15%resulted in greater tibial loading than level running.Running downhill at-10%and-15%resulted in reduced tibial loading compared to level running.There was no difference between+5%or-5%and level running.Conclusion:Running at faster speeds and uphill on gradients≥+10%increased internal tibial loading,whereas slower running and downhill running on gradients≥-10%reduced internal loading.Adapting running speed according to the gradient could be a protective mechanism,providing runners with a strategy to minimize the risk of tibial stress injuries.

BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well understood.Type-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is absent.Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory columns.Parenchymal and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/CD39.LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,cytoarchitecture.These neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent precursors.Dissociated cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage cells.Fluorescence-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in culture.This is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal cords.Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterized by surface BMPRⅡ^(+)hNPCs.Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for>10 passages.Investigations of the role BMPRⅡplays in spinal cord development have primarily relied upon mouse and rat models,with interpolations to human development being derived through inference.Because of significant species differences between murine biology and human,including anatomical dissimilarities in central nervous system(CNS)structure,the findings made in murine models cannot be presumed to apply to human spinal cord development.For these reasons,our human in vitro model offers a novel tool to better understand neurodevelopmental pathways,including BMP signaling,as well as spinal cord injury research and testing drug therapies.

Advantages of nanocarriers for basic research in the field of traumatic brain injury

A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue.To overcome this problem,researchers have begun to focus on nanocarriers and other brain-targeting drug delivery systems.In this review,we summarize the epidemiology,basic pathophysiology,current clinical treatment,the establishment of models,and the evaluation indicators that are commonly used for traumatic brain injury.We also report the current status of traumatic brain injury when treated with nanocarriers such as liposomes and vesicles.Nanocarriers can overcome a variety of key biological barriers,improve drug bioavailability,increase intracellular penetration and retention time,achieve drug enrichment,control drug release,and achieve brain-targeting drug delivery.However,the application of nanocarriers remains in the basic research stage and has yet to be fully translated to the clinic.

Predictive factors and model validation of post-colon polyp surgery Helicobacter pylori infection

BACKGROUND Recently,research has linked Helicobacter pylori(H.pylori)stomach infection to colonic inflammation,mediated by toxin production,potentially impacting colorectal cancer occurrence.AIM To investigate the risk factors for post-colon polyp surgery,H.pylori infection,and its correlation with pathologic type.METHODS Eighty patients who underwent colon polypectomy in our hospital between January 2019 and January 2023 were retrospectively chosen.They were then randomly split into modeling(n=56)and model validation(n=24)sets using R.The modeling cohort was divided into an H.pylori-infected group(n=37)and an H.pylori-uninfected group(n=19).Binary logistic regression analysis was used to analyze the factors influencing the occurrence of H.pylori infection after colon polyp surgery.A roadmap prediction model was established and validated.Finally,the correlation between the different pathological types of colon polyps and the occurrence of H.pylori infection was analyzed after colon polyp surgery.RESULTS Univariate results showed that age,body mass index(BMI),literacy,alcohol consumption,polyp pathology type,high-risk adenomas,and heavy diet were all influential factors in the development of H.pylori infection after intestinal polypectomy.Binary multifactorial logistic regression analysis showed that age,BMI,and type of polyp pathology were independent predictors of the occurrence of H.pylori infection after intestinal polypectomy.The area under the receiver operating characteristic curve was 0.969[95%confidence interval(95%CI):0.928–1.000]and 0.898(95%CI:0.773–1.000)in the modeling and validation sets,respectively.The slope of the calibration curve of the graph was close to 1,and the goodness-of-fit test was P>0.05 in the two sets.The decision analysis curve showed a high rate of return in both sets.The results of the correlation analysis between different pathological types and the occurrence of H.pylori infection after colon polyp surgery showed that hyperplastic polyps,inflammatory polyps,and the occurrence of H.pylori infection were not significantly correlated.In contrast,adenomatous polyps showed a significant positive correlation with the occurrence of H.pylori infection.CONCLUSION Age,BMI,and polyps of the adenomatous type were independent predictors of H.pylori infection after intestinal polypectomy.Moreover,the further constructed column-line graph prediction model of H.pylori infection after intestinal polypectomy showed good predictive ability.

Genetic pathways in cerebral palsy:a review of the implications for precision diagnosis and understanding disease mechanisms

Ce rebral palsy is a diagnostic term utilized to describe a group of permanent disorders affecting movement and posture.Patients with cerebral palsy are often only capable of limited activity,resulting from non-progressive disturbances in the fetal or neonatal brain.These disturbances severely impact the child’s daily life and impose a substantial economic burden on the family.Although cerebral palsy encompasses various brain injuries leading to similar clinical outcomes,the unde rstanding of its etiological pathways remains incomplete owing to its complexity and heterogeneity.This review aims to summarize the current knowledge on the genetic factors influencing cerebral palsy development.It is now widely acknowledged that genetic mutations and alterations play a pivotal role in cerebral palsy development,which can be further influenced by environmental fa ctors.Des pite continuous research endeavors,the underlying fa ctors contributing to cerebral palsy remain are still elusive.However,significant progress has been made in genetic research that has markedly enhanced our comprehension of the genetic factors underlying cerebral palsy development.Moreove r,these genetic factors have been categorized based on the identified gene mutations in patients through clinical genotyping,including thrombosis,angiogenesis,mitochondrial and oxidative phosphorylation function,neuronal migration,and cellular autophagy.Furthermore,exploring targeted genotypes holds potential for precision treatment.In conclusion,advancements in genetic research have substantially improved our understanding of the genetic causes underlying cerebral palsy.These breakthroughs have the potential to pave the way for new treatments and therapies,consequently shaping the future of cerebral palsy research and its clinical management.The investigation of cerebral palsy genetics holds the potential to significantly advance treatments and management strategies.By elucidating the underlying cellular mechanisms,we can develop to rgeted interventions to optimize outcomes.A continued collaboration between researchers and clinicians is imperative to comprehensively unravel the intricate genetic etiology of cerebral palsy.

A growth-regulating factor 7(GRF7)-mediated gene regulatory network promotes leaf growth and expansion in sugarcane

Knowledge of the function of growth-regulating factors(GRFs)in sugarcane(Saccharum officinarum and S.spontaneum)growth and development could assist breeders in selecting desirable plant architectures.However,limited information about GRFs is available in Saccharum due to their polyploidy.In this study,22 GRFs were identified in the two species and their conserved domains,gene structures,chromosome location,and synteny were characterized.GRF7 expression varied among tissues and responded to diurnal rhythm.SsGRF7-YFP was localized preferentially in the nucleus and appears to act as a transcriptional cofactor.SsGRF7 positively regulated the size and length of rice leaves,possibly by regulating cell size and plant hormones.Of seven potential transcription factors binding to the SsGRF7 promoter in S.spontaneum,four showed positive expression patterns,and two showed negative expression patterns relative to SsGRF7.

The roles of macrophage migration inhibitory factor in retinal diseases

Macrophage migration inhibitory factor(MIF),a multifunctional cytokine,is secreted by various cells and participates in inflammatory reactions,including innate and adaptive immunity.There are some evidences that MIF is involved in many vitreoretinal diseases.For example,MIF can exacerbate many types of uveitis;measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment.MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage.Furthermore,MIF is critical for retinal/choroidal neovascularization,especially complex neovascularization.MIF exacerbates retinal degeneration;thus,anti-MIF therapy may help to mitigate retinal degeneration.MIF protects uveal melanoma from attacks by natural killer cells.The mechanism underlying the effects of MIF in these diseases has been demonstrated:it binds to cluster of differentiation 74,inhibits the c-Jun N-terminal kinase pathway,and triggers mitogen-activated protein kinases,extracellular signal-regulated kinase-1/2,and the phosphoinositide-3-kinase/Akt pathway.MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway.This review focuses on the structure and function of MIF and its receptors,including the effects of MIF on uveal inflammation,retinal degeneration,optic neuropathy,retinal/choroidal neovascularization,and uveal melanoma.

The dorsal root ganglion as a target for neurorestoration in neuropathic pain

Neuropathic pain is a severe and chronic condition widely found in the general population.The reason for this is the extensive variety of damage or diseases that can spark this unpleasant constant feeling in patients.During the processing of pain,the dorsal root ganglia constitute an important region where dorsal root ganglion neurons play a crucial role in the transmission and propagation of sensory electrical stimulation.Furthermore,the dorsal root ganglia have recently exhibited a regenerative capacity that should not be neglected in the understanding of the development and resolution of neuropathic pain and in the elucidation of innovative therapies.Here,we will review the complex interplay between cells(satellite glial cells and inflammatory cells)and factors(cytokines,neurotrophic factors and genetic factors)that takes place within the dorsal root ganglia and accounts for the generation of the aberrant excitation of primary sensory neurons occurring in neuropathic pain.More importantly,we will summarize an updated view of the current pharmacologic and nonpharmacologic therapies targeting the dorsal root ganglia for the treatment of neuropathic pain.

Predictive factors for percutaneous nephrolithotomy bleeding risks

Objective:This study aimed to identify predictive factors for percutaneous nephrolithotomy(PCNL)bleeding risks.With better risk stratification,bleeding in high-risk patient can be anticipated and facilitates early identification.Methods:A prospective observational study of PCNL performed at our institution was done.All adults with radio-opaque renal stones planned for PCNL were included except those with coagulopathy,planned for additional procedures.Factors including gender,co-morbidities,body mass index,stone burden,puncture site,tract dilatation size,operative position,surgeon's seniority,and operative duration were studied using stepwise multivariate regression analysis to identify the predictive factors associated with higher estimated hemoglobin(Hb)deficiency.Results:Overall,4.86%patients(n=7)received packed cells transfusion.The mean estimated Hb deficiency was 1.3(range 0-6.5)g/dL and the median was 1.0 g/dL.Stepwise multivariate regression analysis revealed that absence of hypertension(p=0.024),puncture site(p=0.027),and operative duration(p=0.023)were significantly associated with higher estimated Hb deficiency.However,the effect sizes are rather small with partial eta-squared of 0.037,0.066,and 0.038,respectively.Observed power obtained was 0.621,0.722,and 0.625,respectively.Other factors studied did not correlate with Hb difference.Conclusion:Hypertension,puncture site,and operative duration have significant impact on estimated Hb deficiency during PCNL.However,the effect size is rather small despite adequate study power obtained.Nonetheless,operative position(supine or prone),puncture number,or tract dilatation size did not correlate with Hb difference.The mainstay of reducing bleeding in PCNL is still meticulous operative technique.Our study findings also suggest that PCNL can be safely done by urology trainees under supervision in suitably selected patient,without increasing risk of bleeding.

Identifying the best common factor model via exploratory eactor analysis

Currently,there is no solid criterion for judging the quality of the estimators in factor analysis.This paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor extraction.The proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor model.Examples are presented to demonstrate how the method is implemented and to verify its effectiveness.

Rate-limiting factors in hydrate decomposition through depressurization across various scales:A mini-review

Natural gas hydrate is an energy resource for methane that has a carbon quantity twice more than all traditional fossil fuels combined.However,their practical application in the field has been limited due to the challenges of long-term preparation,high costs and associated risks.Experimental studies,on the other hand,offer a safe and cost-effective means of exploring the mechanisms of hydrate dissociation and optimizing exploitation conditions.Gas hydrate decomposition is a complicated process along with intrinsic kinetics,mass transfer and heat transfer,which are the influencing factors for hydrate decomposition rate.The identification of the rate-limiting factor for hydrate dissociation during depressurization varies with the scale of the reservoir,making it challenging to extrapolate findings from laboratory experiments to the actual exploitation.This review aims to summarize current knowledge of investigations on hydrate decomposition on the subject of the research scale(core scale,middle scale,large scale and field tests)and to analyze determining factors for decomposition rate,considering the various research scales and their associated influencing factors.

Assessment of soil erosion in the Irga watershed on the eastern edge of the Chota Nagpur Plateau,India

Human activities to improve the quality of life have accelerated the natural rate of soil erosion.In turn,these natural disasters have taken a great impact on humans.Human activities,particularly the conversion of vegetated land into agricultural land and built-up area,stand out as primary contributors to soil erosion.The present study investigated the risk of soil erosion in the Irga watershed located on the eastern fringe of the Chota Nagpur Plateau in Jharkhand,India,which is dominated by sandy loam and sandy clay loam soil with low soil organic carbon(SOC)content.The study used the Revised Universal Soil Loss Equation(RUSLE)and Geographical Information System(GIS)technique to determine the rate of soil erosion.The five parameters(rainfall-runoff erosivity(R)factor,soil erodibility(K)factor,slope length and steepness(LS)factor,cover-management(C)factor,and support practice(P)factor)of the RUSLE were applied to present a more accurate distribution characteristic of soil erosion in the Irga watershed.The result shows that the R factor is positively correlated with rainfall and follows the same distribution pattern as the rainfall.The K factor values in the northern part of the study area are relatively low,while they are relatively high in the southern part.The mean value of the LS factor is 2.74,which is low due to the flat terrain of the Irga watershed.There is a negative linear correlation between Normalized Difference Vegetation Index(NDVI)and the C factor,and the high values of the C factor are observed in places with low NDVI.The mean value of the P factor is 0.210,with a range from 0.000 to 1.000.After calculating all parameters,we obtained the average soil erosion rate of 1.43 t/(hm^(2)•a),with the highest rate reaching as high as 32.71 t/(hm^(2)•a).Therefore,the study area faces a low risk of soil erosion.However,preventative measures are essential to avoid future damage to productive and constructive activities caused by soil erosion.This study also identifies the spatial distribution of soil erosion rate,which will help policy-makers to implement targeted soil erosion control measures.

Development and validation of a nomogram model for predicting the risk of gallstone recurrence after gallbladder-preserving surgery

Background:The high incidence of gallstone recurrence was a major concern for laparoscopic gallbladderpreserving surgery.This study aimed to investigate the risk factors for gallstone recurrence after gallbladder-preserving surgery and to establish an individualized nomogram model to predict the risk of gallstone recurrence.Methods:The clinicopathological and follow-up data of 183 patients who were initially diagnosed with gallstones and treated with gallbladder-preserving surgery at our hospital from January 2012 to January 2019 were retrospectively collected.The independent predictive factors for gallstone recurrence following gallbladder-preserving surgery were identified by multivariate logistic regression analysis.A nomogram model for the prediction of gallstone recurrence was constructed based on the selected variables.The C-index,receiver operating characteristic(ROC)curve and calibration curve were used to evaluate the predictive power of the nomogram model for gallstone recurrence.Results:During the follow-up period,a total of 65 patients experienced gallstone recurrence,and the recurrence rate was 35.5%.Multivariate logistic regression analysis revealed that the course of gallstones>2 years[odds ratio(OR)=2.567,95%confidence interval(CI):1.270-5.187,P=0.009],symptomatic gallstones(OR=2.589,95%CI:1.059-6.329,P=0.037),multiple gallstones(OR=2.436,95%CI:1.133-5.237,P=0.023),history of acute cholecystitis(OR=2.778,95%CI:1.178-6.549,P=0.020)and a greasy diet(OR=2.319,95%CI:1.186-4.535,P=0.014)were independent risk factors for gallstone recurrence after gallbladder-preserving surgery.A nomogram model for predicting the recurrence of gallstones was established based on the above five variables.The results showed that the C-index of the nomogram model was 0.692,suggesting it was valuable to predict gallstone recurrence.Moreover,the calibration curve showed good consistency between the predicted probability and actual probability.Conclusions:The nomogram model for the prediction of gallstone recurrence might help clinicians develop a proper treatment strategy for patients with gallstones.Gallbladder-preserving surgery should be cautiously considered for patients with high recurrence risks.

The Variation of Plankton Community Structure in Artificial Reef Area and Adjacent Waters in Haizhou Bay

Plankton are an important component of marine protected areas(MPAs),and its communities would require much smaller interpatch distances to ensure connection among MPAs.According to the survey from MPAs dominated by artificial reefs and adjacent waters(estuary area(EA),aquaculture area(AA),artificial reef area(ARA),natural area(NA)and comprehensive effect area(CEA))in Haizhou Bay in spring and autumn,we analyzed phyto-zooplankton composition,abundance and biomass,and correlation with hydrologic variables to gain information about the forces that structure the plankton.The results showed that the dominant zooplankton were copepods(spring,98.9%;autumn,94.2%),while the phytoplankton were mainly composed of Bacillariophyta(spring,61.8%;autumn,95.6%).The RDA results showed that temperature,salinity and depth highly associated with the distribution and composition of plankton species among the habitats than other factors in spring;temperature,Chla and DO had the strongest influence in autumn.The zooplankton in the ARA and AA ecosystems basically contained the same species as those in other habitats,and each habitat also exhibited a relatively unique combination of plankton species.The structures of the EA zooplankton in spring and the EA phytoplankton in both seasons were much different than other habitats,which may have been caused by factors such as currents and tides.We concluded that there exists similarity of the plankton community between artificial reef area and adjacent waters,whereas the EAs may be relatively independent systems.Therefore,these interaction between plankton community should be considered when designing MPA networks,and ocean circulations should be considered more than the environmental factors.

Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin

Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated.

Evolutionary history shapes variation of wood density of tree species across the world

The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been tested.Using a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide,we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree species.We assessed phylogenetic signal in different taxonomic(e.g.,angiosperms and gymnosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phylogenetic patterns of wood density,and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary history(i.e.,phylogenetic relatedness among species and lineages)in driving global wood density variation.We found that wood density displayed a significant phylogenetic signal.Wood density differed among different biomes and climatic zones,with higher mean values of wood density in relatively drier regions(highest in subtropical desert).Our study revealed that at a global scale,for angiosperms and gymnosperms combined,phylogeny and species(representing the variance explained by taxonomy and not direct explained by long-term evolution process)explained 84.3%and 7.7%of total wood density variation,respectively,whereas current environment explained 2.7%of total wood density variation when phylogeny and species were taken into account.When angiosperms and gymnosperms were considered separately,the three proportions of explained variation are,respectively,84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for gymnosperms.Our study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density.