The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment.Previous studies have suggested that there is an auditory“where”pathway in the cortex for proce...The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment.Previous studies have suggested that there is an auditory“where”pathway in the cortex for processing sound locations.The neural activation in regions along this pathway encodes sound locations by opponent hemifield coding,in which each unilateral region is activated by sounds coming from the contralateral hemifield.However,it is still unclear how these regions interact with each other to form a unified representation of the auditory space.In the present study,we investigated whether functional connectivity in the auditory“where”pathway encoded sound locations during passive listening.Participants underwent functional magnetic resonance imaging while passively listening to sounds from five distinct horizontal locations(−90°,−45°,0°,45°,90°).We were able to decode sound locations from the functional connectivity patterns of the“where”pathway.Furthermore,we found that such neural representation of sound locations was primarily based on the coding of sound lateralization angles to the frontal midline.In addition,whole-brain analysis indicated that functional connectivity between occipital regions and the primary auditory cortex also encoded sound locations by lateralization angles.Overall,our results reveal a lateralization-angle-based representation of sound locations encoded by functional connectivity patterns,which could add on the activation-based opponent hemifield coding to provide a more precise representation of the auditory space.展开更多
Musical training can counteract age-related decline in speech perception in noisy environments.However,it remains unclear whether older non-musicians and musicians rely on functional compensation or functional preserv...Musical training can counteract age-related decline in speech perception in noisy environments.However,it remains unclear whether older non-musicians and musicians rely on functional compensation or functional preservation to counteract the adverse efects of aging.This study utilized resting-state functional connectivity(FC)to investigate functional lateralization,a fundamental organization feature,in older musicians(OM),older non-musicians(ONM),and young non-musicians(YNM).Results showed that OM outperformed ONM and achieved comparable performance to YNM in speech-in-noise and speech-in-speech tasks.ONM exhibited reduced lateralization than YNM in lateralization index(LI)of intrahemispheric FC(LI_intra)in the cingulo-opercular network(CON)and LI of interhemispheric heterotopic FC(LI_he)in the language network(LAN).Conversely,OM showed higher neural alignment to YNM(i.e.,a more similar lateralization pattern)compared to ONM in CON,LAN,frontoparietal network(FPN),dorsal attention network(DAN),and default mode network(DMN),indicating preservation of youth-like lateralization patterns due to musical experience.Furthermore,in ONM,stronger left-lateralized and lower alignment-to-young of LI_intra in the somatomotor network(SMN)and DAN and LI_he in DMN correlated with better speech performance,indicating a functional compensation mechanism.In contrast,stronger right-lateralized LI_intra in FPN and DAN and higher alignment-to-young of LI_he in LAN correlated with better performance in OM,suggesting a functional preservation mechanism.These fndings highlight the diferential roles of functional preservation and compensation of lateralization in speech perception in noise among elderly individuals with and without musical expertise,ofering insights into successful aging theories from the lens of functional lateralization and speech perception.展开更多
Brain asymmetry for processing visual information is widespread in animals.However,it is still unknown how the complexity of the underlying neural network activities represents this asymmetrical pattern in the brain.I...Brain asymmetry for processing visual information is widespread in animals.However,it is still unknown how the complexity of the underlying neural network activities represents this asymmetrical pattern in the brain.In the present study,we investigated this complexity using the approximate entropy(ApEn)protocol for electroencephalogram(EEG)recordings from the forebrain and midbrain while the music frogs(Nidirana daunchina)attacked prey stimulus.The results showed that(1)more significant prey responses were evoked by the prey stimulus presented in the right visual field than that in the left visual field,consistent with the idea that right-eye preferences for predatory behaviors exist in animals including anurans;(2)in general,the ApEn value of the left hemisphere(especially the left mesencephalon)was greatest under various stimulus conditions,suggesting that visual lateralization could be reflected by the dynamics of underlying neural network activities and that the stable left-hemisphere dominance of EEG ApEn may play an important role in maintaining this brain asymmetry.展开更多
Asymmetries in bilateral organisms attract a lot of curiosity given that they are conspicuous departures from the norm.They allow the investigation of the integration at different levels of biological organization.Her...Asymmetries in bilateral organisms attract a lot of curiosity given that they are conspicuous departures from the norm.They allow the investigation of the integration at different levels of biological organization.Here we study whether and how behavioral and asymmetrical anatomical traits coevolved and work together.We ask if asymmetry is determined locally for each trait or at a whole individual level in a species bearing conspicuous asymmetrical genitalia.Asymmetric genitalia evolved in many species;however,in most cases the direction of asymmetry is fixed.Therefore,it has been rarely determined if there is an association between the direction of asymmetry in genitalia and other traits.In onesided livebearer fish of the genus Jenynsia(Cyprinodontiformes,Anablepidae),the anal fin of males is modified into a gonopodium,an intromittent organ that serves to inseminate females.The gonopodium shows a conspicuous asymmetry,with its tip bending either to the left or the right.By surveying 13 natural populations of Jenynsia lineata,we found that both genital morphs are equally common in wild populations.In a series of experiments in a laboratory population,we discovered asymmetry and lateralization for multiple other traits;yet,the degree of integration varied highly among them.Lateralization in exploratory behavior in response to different stimuli was not associated with genital morphology.Interestingly,the direction of genital asymmetry was positively correlated with sidedness of mating preference and the number of neuromasts in the lateral line.This suggests integration of functionally linked asymmetric traits;however,there is no evidence that asymmetry is determined at the whole individual level in our study species.展开更多
Functional asymmetries, for example, the preferential involvement of 1 brain hemisphere to process stimuli, may increase brain efficiency and the capacity to carry out tasks simultaneously. We investigated which hemis...Functional asymmetries, for example, the preferential involvement of 1 brain hemisphere to process stimuli, may increase brain efficiency and the capacity to carry out tasks simultaneously. We investigated which hemisphere was primarily invoIved in processing acoustic stimuli in goats using a headorienting paradigm. Three playbacks using goat vocalizations recorded in different contexts: food anticipation (positive), isolation (negative), food frustration (negative), as well as 1 playback involving dog barks (negative) were presented on the left and right sides of the test subjects simultaneously. The head-orienting response (left or right) and latency to resume feeding were recorded. The direction of the head-orienting response did not differ between the various playbacks. However, when the head-orienting response was tested against chanee level, goats showed a right bias regardless of the stimuli presented. Goats responded more to dog barks than to food frustration calls, whereas responses to food anticipation and isolation calls were intermediate. In addition, the latency to resume feeding, an indicator of fear reaction, was not affected by the kind of vocalization presented. These results provide evidence for asymmetries in goat vocal perceptio n of emotional-li nked con specific and heterospecific calls. They also suggest involvement of the left brain hemisphere for processing acoustic stimuli, which might have been perceived as familiar and non -threate ning.展开更多
BACKGROUND： Previous studies have analyzed cerebral activation and lateralization of cognitive functions, as well as cerebellar function with reference to high-level cognitive processing. However, there has been very...BACKGROUND： Previous studies have analyzed cerebral activation and lateralization of cognitive functions, as well as cerebellar function with reference to high-level cognitive processing. However, there has been very little research on systematization and diversification. In particular, there are no reports on cerebellar lateralization, although reliable results have been reported on cerebral lateralization. OBJECTIVE： This study analyzed cerebellar activation and lateralization in relation to verbal and visuospatial tasks using functional magnetic resonance imaging （fMRI）. DESIGN, TIME AND SETTING： A block design for fMRI observation was performed at the fMRI Laboratory, Brain Science Research Center, Korea Advanced Institute of Science and Technology from May 2006 to September 2008. PARTICIPANTS： Sixteen healthy, male, college students, aged （23.3 ± 0.5） years, and 16 healthy, male, college students, aged （21.5 ± 2.3） years, participated in the study, respectively. METHODS： Verbal and visuospatial tasks were presented while functional brain images were acquired using a 3T fMRI system. Verbal analogy testing required the subject to select the word with the same relationship as one of the given words. Verbal antonym testing required the subject to select the word with a different meaning among four words. Visuospatial tasks involved selecting a shape that corresponded to a given figure with four examples, as well as selecting a development figure of a diagram. MAIN OUTCOME MEASURES： Changes in cerebellar activation and lateralization between two cognition tasks. RESULTS： Bilateral hemisphere Iobules VI and IX, right hemisphere Iobule VIII, bilateral hemisphere Iobules Crus I, and vermis Iobule IV, V, and Vl were closely related to verbal tasks in comparison to visuospatial tasks. Conversely, bilateral hemisphere Iobules IV and V, as well as the right hemisphere Iobule VI, were closely related to visuospatial tasks compared to verbal tasks. There was no great difference between the number of activated voxels in the cerebellums during the tasks, and cerebellar lateralization was not observed. CONCLUSION： In the cerebellum, the activation region, but not lateralization, was different between verbal and visuospatial tasks.展开更多
Behavioural lateralization,which reflects the functional specializations of the two brain hemispheres,is assumed to play an important role in cooperative intraspecific interactions.However,there are few studies focuse...Behavioural lateralization,which reflects the functional specializations of the two brain hemispheres,is assumed to play an important role in cooperative intraspecific interactions.However,there are few studies focused on the lateralization in cooperative behaviours of individuals,especially in a natural setting.In the present study,we investigated Iateralized spatial interactions between the partners in life-long monogamous pairs.The male-female pairs of two geese species(barnacle,Branta leucopsis,and white-fronted,Anser albifrons geese),were observed during different stages of the annual cycle in a variety of conditions.In geese flocks,we recorded which visual hemifield(left/right)the following partner used to monitor the leading partner relevant to the type of behaviour and the disturbance factors.In a significant majority of pairs,the following bird viewed the leading partner with the left eye during routine behaviours such as resting and feeding in undisturbed conditions.This behavioural lateralization,implicating the right hemisphere processing,was consistent across the different aggregation sites and years of the study.In contrast,no significant bias was found in a variety of geese behaviours associated with enhanced disturbance(when alert on water,flying or fleeing away when disturbed,feeding during the hunting period,in urban area feeding and during moulting).We hypothesize that the increased demands for right hemisphere processing to deal with stressful and emergency situations may interfere with the manifestation of lateralization in social interactions.展开更多
Lateralization of cognitive functions influences a large number of fitness-related behaviors and shows,in most species,substantial variation in strength and direction.Laboratory works and field data have suggested tha...Lateralization of cognitive functions influences a large number of fitness-related behaviors and shows,in most species,substantial variation in strength and direction.Laboratory works and field data have suggested that this variation is often due to adaptive phenotypic plasticity.Strong lateralization should be favored in some ecological conditions,for example,under high risk of predation.For anuran tadpoles,the presence of cover affects predation risk,with tadpoles being more exposed to predators in environments with reduced cover.We tested the hypothesis that the amount of cover experienced early in life affects lateralization in the edible frog,Pelophylax escu-lentus,tadpoles.We exposed embryos and larvae to high or low vegetation cover environments.For half of the subjects,the treatment was constant whereas the remaining subjects were switched to the opposite treatment after hatching.In agreement with the theoretical expectation,tadpoles exposed to low vegetation cover for the entire development were more lateralized and showed a stronger alignment in directionality of lateralization compared with tadpoles exposed to high vege-tation cover.This indicates a possible role of natural variation in vegetation abundance and deve卜opmental plasticity as determinants of between-population and between-individual differences in lateralization.We also found that shifting from high to low vegetation cover treatments and vice versa disrupted lateralization alignment,suggesting that developmental trajectories for this trait are determined at the embryonic stage and need environmental stability to be fully expressed.展开更多
Brain lateralization for language in high-functioning children with autism spectrum conditions (ASC) and sensory processing were explored as a part of a neuropsychological profile. A dichotic listening test and the Lu...Brain lateralization for language in high-functioning children with autism spectrum conditions (ASC) and sensory processing were explored as a part of a neuropsychological profile. A dichotic listening test and the Luria laterality subtest were administered to all participants (including controls) and the sensory profile test only to the ASC group. The usual right ear advantage was not exhibited by children with ASC and anomalies in auditory filtering were found. The sensory profile of 60% of the sample was characterized by hypersensitivity to auditory stimuli, hyposensitivity to vestibular information, high emotional reactions to sensory experiences, poor psychosocial coping strategies, high distractibility and inability to interpret body and facial language. Hyper-responsiveness to environmental auditory stimuli was significantly associated with impaired attention. Similarly, non-adaptive responses to sensory quotidian experiences were strongly connected to poor coping strategies. Our results, although preliminary, contribute to emphasizing the importance of including additional assessment methods such as the dichotic listening and the sensory profile questionnaire in the evaluation of cognitive profile in high-functioning children with ASC to plan an individualized psycho-educative intervention.展开更多
The objective is to study changes in EEG time-domain Kolmogorov entropy and cortical lateralization of brain function areas during complex problem solving mental task in healthy human subjects. EEG data for healthy su...The objective is to study changes in EEG time-domain Kolmogorov entropy and cortical lateralization of brain function areas during complex problem solving mental task in healthy human subjects. EEG data for healthy subjects are acquired during complex problem solving mental task using a net of 6 electrodes. The subject was given a nontrivial multiplication problem to solve and the signals were recorded for 10s during the task. Kolmogorov entropy values during the task were calculated. It was found that Kolmogorov entropy values were obviously greater in P4 channel (right) than ones in P3 channel (left) during complex problem solving task. It indicated that all subjects presented significant left parietal lateralization for the total frequency spectrum. These results suggest that it may be possible to noninvasively lateralize, and even eventually localize, cerebral regions essential for particular mental tasks from scalp EEG data.展开更多
In recent decades, functional magnetic resonance imaging (fMRI) has proven to be more effective than the Wada test in the evaluation of language lateralization in special populations such as epileptic patients and chi...In recent decades, functional magnetic resonance imaging (fMRI) has proven to be more effective than the Wada test in the evaluation of language lateralization in special populations such as epileptic patients and children. However, fMRI requires that subjects remain motionless during data acquisition, making the assessment of receptive and expressive language difficult in young children and population with special needs. Near-Infrared spectroscopy (NIRS) is a non- invasive technique that has proven to be more tolerant to motion artifacts. The aim of the present study was to investigate the use of NIRS to assess receptive language patterns using a story listening paradigm. Four native French-speakers listened to stories read aloud by a bilingual speaker in both French and Arabic. To determine if the signal recorded was affected by episodic memory processes, a familiar story and an unknown story were presented. Results showed that listening to stories in French elicited a significantly higher left lateralized response than listening to stories in Arabic, independently of the familiarity of the story. These results confirm that NIRS is a useful non-invasive technique to assess receptive language in adults and can be used to investigate language lateralization among children and epileptic patients slated for epilepsy surgery.展开更多
This study investigated the effect of transcranial direct current stimulation（t DCS） polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive task...This study investigated the effect of transcranial direct current stimulation（t DCS） polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive tasks. Thirty healthy participants with no neurological disorders were recruited to participate in this study. Participants were randomly allocated into active or control condition. For the active condition, t DCS intensity was 2 m A with stimulation applied for 15 minutes to the right hemisphere（t DCS condition）. For the sham control, electrodes were placed in the same position, but the stimulator was turned off after 30 seconds（sham condition）. The tapping and tracking task tests were performed before and after for both conditions. Univariate analysis revealed significant difference only in the tracking task. For direct comparison of both tasks within each group, the tracking task had significantly higher Z score than the tapping task in the t DCS group（P 〈 0.05）. Thus, our study indicates that stimulation of the right hemisphere using t DCS can effectively improve visuomotor（tracking） task over simple repetitive（tapping） task.展开更多
This paper reviews research on hemispheric lateralization.There are neurological evidences for the lateralization of speech and language functions and inter-and intrahemispherical differences between males and females...This paper reviews research on hemispheric lateralization.There are neurological evidences for the lateralization of speech and language functions and inter-and intrahemispherical differences between males and females.The results for the study of lateralization and bilingualism are mixed,proving the complexity and multidimensionality of lateralization.展开更多
Costs and benefits of brain lateralization may depend on environmental conditions.Growing evidence indicates that the development of brain functional asymmetries is adaptively shaped by the environmental conditions ex...Costs and benefits of brain lateralization may depend on environmental conditions.Growing evidence indicates that the development of brain functional asymmetries is adaptively shaped by the environmental conditions experienced during early life.Food availability early in life could act as a proxy of the environmental conditions encountered during adulthood,but its potential modulatory effect on lateralization has received little attention.We increased food supply from egg laying to early nestling rearing in a wild population of lesser kestrels Falco naumanni,a sexually dimorphic raptor,and quantified the lateralization of preening behavior(head turning direction).As more lateralized individuals may perform better in highly competitive contexts,we expected that extra food provisioning,by reducing the level of intra-brood competition for food,would reduce the strength of lateralization.We found that extra food provisioning improved nestling growth,but it did not significantly affect the strength or direction of nestling lateralization.In addition,maternal body condition did not explain variation in nestling lateralization.Independently of extra food provisioning,the direction of lateralization differed between the sexes,with female nestlings turning more often toward their right.Our findings indicate that early food availability does not modulate behavioral lateralization in a motor task,suggesting limited phenotypic plasticity in this trait.展开更多
Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective d...Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective degeneration of motor neurons in the brain,brainstem,and spinal cord,as well as abnormal protein deposition in the cytoplasm of neurons and glial cells.The biological markers under extensive scrutiny are predominantly located in the cerebrospinal fluid,blood,and even urine.Among these biomarke rs,neurofilament proteins and glial fibrillary acidic protein most accurately reflect the pathologic changes in the central nervous system,while creatinine and creatine kinase mainly indicate pathological alterations in the peripheral nerves and muscles.Neurofilament light chain levels serve as an indicator of neuronal axonal injury that remain stable throughout disease progression and are a promising diagnostic and prognostic biomarker with high specificity and sensitivity.However,there are challenges in using neurofilament light chain to diffe rentiate amyotrophic lateral sclerosis from other central nervous system diseases with axonal injury.Glial fibrillary acidic protein predominantly reflects the degree of neuronal demyelination and is linked to non-motor symptoms of amyotrophic lateral sclerosis such as cognitive impairment,oxygen saturation,and the glomerular filtration rate.TAR DNA-binding protein 43,a pathological protein associated with amyotrophic lateral sclerosis,is emerging as a promising biomarker,particularly with advancements in exosome-related research.Evidence is currently lacking for the value of creatinine and creatine kinase as diagnostic markers;however,they show potential in predicting disease prognosis.Despite the vigorous progress made in the identification of amyotrophic lateral sclerosis biomarkers in recent years,the quest for definitive diagnostic and prognostic biomarke rs remains a formidable challenge.This review summarizes the latest research achievements concerning blood biomarkers in amyotrophic lateral sclerosis that can provide a more direct basis for the differential diagnosis and prognostic assessment of the disease beyond a reliance on clinical manifestations and electromyography findings.展开更多
The work is to explore the relationship between the levels of cytokines(IL-1β and IL-6)in C57BL/6J mice treated with MPTP and brain lateralization.By using paw preference test,right-pawed,left-pawed mice models were ...The work is to explore the relationship between the levels of cytokines(IL-1β and IL-6)in C57BL/6J mice treated with MPTP and brain lateralization.By using paw preference test,right-pawed,left-pawed mice models were established.Following single injection of 1-methyl-4-phenyl-2,3,6-tetrahydropyrid(MPTP)(40 mg/kg)to impair dopaminergic neuron,enzyme linked immunosorbent assay(ELISA)kits were used for detection of plasma levels of cytokines.The results showed that in saline treated C57BL/6J mice(control),there was no obvious difference observed between left-pawed and right-pawed mice in plasma levels of IL-1β and IL-6.In MPTP treated mice,there was no difference between level of IL-1β in left-pawed mice and that in right-pawed ones in statistics,that is,they were increased on day 1 and day 3,but decreased on day 6.The plasma level of IL-6 was lower in left-pawed than that in right-pawed mice (p<0.005)after MPTP treatment. On day 1 and day 3,the level of IL-6 was almost the same as control;on day 6,it was significantly increased, higher than that of control(p<0.001)in left-pawed mice.While in right-pawed mice,on day 1 and day 3,it was no different from control,too.And on day 6,it significantly increased in compared with control(p<0.005).In conclusion,the level of plasma IL-6 of C57BL/6J mice treated with MPTP increased.The variation of IL-6 was correlated to brain lateralization.Cellular & Molecular Immunology.2004;1(3):219-223.展开更多
The muscular system plays a critical role in the human body by governing skeletal movement,cardiovascular function,and the activities of digestive organs.Additionally,muscle tissues serve an endocrine function by secr...The muscular system plays a critical role in the human body by governing skeletal movement,cardiovascular function,and the activities of digestive organs.Additionally,muscle tissues serve an endocrine function by secreting myogenic cytokines,thereby regulating metabolism throughout the entire body.Maintaining muscle function requires iron homeostasis.Recent studies suggest that disruptions in iron metabolism and ferroptosis,a form of iron-dependent cell death,are essential contributors to the progression of a wide range of muscle diseases and disorders,including sarcopenia,cardiomyopathy,and amyotrophic lateral sclerosis.Thus,a comprehensive overview of the mechanisms regulating iron metabolism and ferroptosis in these conditions is crucial for identifying potential therapeutic targets and developing new strategies for disease treatment and/or prevention.This review aims to summarize recent advances in understanding the molecular mechanisms underlying ferroptosis in the context of muscle injury,as well as associated muscle diseases and disorders.Moreover,we discuss potential targets within the ferroptosis pathway and possible strategies for managing muscle disorders.Finally,we shed new light on current limitations and future prospects for therapeutic interventions targeting ferroptosis.展开更多
BACKGROUND:Tracheal intubation(TI)is a fundamental procedure for securing the airway or assisting ventilation in emergency medicine.Tracheal intubation in the lateral position(TILP)has been utilized in clinical practi...BACKGROUND:Tracheal intubation(TI)is a fundamental procedure for securing the airway or assisting ventilation in emergency medicine.Tracheal intubation in the lateral position(TILP)has been utilized in clinical practice,demonstrating potential advantages in specific scenarios,including emergency settings.However,there is a lack of comprehensive reviews and practical protocols on TILP application.To address this gap,we performed a narrative review,and provided evidence-based recommendations to formulate a practice protocol,to assist clinicians to effectively apply TILP.METHODS:We conducted a narrative review of TILP applications and developed recommendations based on clinical research evidence and clinical experience.Delphi method was used among the TILP consortium to grade the strength of the recommendations and to help reach consensus.The practice protocols were formulated as warranted by advancements in medical knowledge,technology,and practice.RESULTS:This narrative review summarized the current evidence on TILP application,highlighting its safety,efficacy,challenges,and potential complications.In total,24 recommendations and a clinical protocol for TILP application in emergency patients were established.CONCLUSION:TILP is a valuable technique in emergency medicine.We reviewed its application in emergency settings and formulated recommendations along with a clinical practice protocol.Future studies are needed to evaluate the safety and efficacy of TILP,broaden its scope of application,and explore effective training protocols.展开更多
The models constructed by particle flow simulation method can effectively simulate the heterogeneous substance characteristics and failure behaviors of rocks.However,existing contact models overlook the rock cracks,an...The models constructed by particle flow simulation method can effectively simulate the heterogeneous substance characteristics and failure behaviors of rocks.However,existing contact models overlook the rock cracks,and the various simulation methods that do consider cracks still exhibit certain limitations.In this paper,based on Flat-Joint model and Linear Parallel Bond model,a crack contact model considering linked substance in the crack is proposed by splitting the crack contact into two portions:linked portion and unlinked portion for calculation.The new contact model considers the influence of crack closure on the contact force-displacement law.And a better compressive tensile strength ratio(UCS/T)was obtained by limiting the failure of the contact bond to be solely controlled by the contact force and moment of the linked portion.Then,by employing the FISH Model tool within the Particle Flow Code,the contact model was constructed and verified through contact force–displacement experiments and loading-unloading tests with cracked model.Finally,the contact model was tested through simulations of rock mechanics experiments.The results indicate that the contact model can effectively simulate the axial and lateral strain laws of rocks simultaneously and has a relatively good reproduction of the bi-modularity of rocks.展开更多
Mountainous areas are the priority for forest restoration in semiarid regions,with hillslopes serving as the basic units of mountains.Precipitation is the only water source in these regions,and the uneven distribution...Mountainous areas are the priority for forest restoration in semiarid regions,with hillslopes serving as the basic units of mountains.Precipitation is the only water source in these regions,and the uneven distribution of hillslope soil moisture replenishment after precipitation determines vegetation survival and growth.Therefore,in this study experiments were performed on a hillslope in the Liupan Mountains,Ningxia Hui Autonomous Region,China,to quantify the unevenness of soil moisture replenishment.Soil water content(SWC)in the 0–60 cm layer and precipitation were monitored throughout the growing season in 2020 and 2021.The results showed that(1)Annual soil moisture replenishment was the highest at the mid-slope position,with an average of 309.9 mm,especially under moderate and heavy rain grade conditions,reaching 38.7% and 30.8% of the total replenishment,respectively;(2)Vertical replenishment played a dominant role in the total replenishment,accounting for 82.8%;lateral replenishment played an important but lesser role,accounting for up to 17.2% of the total replenishment;(3)Based on a soil moisture replenishment model established in this study,the maximal replenishment occurred at 90 m from the top of the slope;(4)The dominant factors contributing to the soil moisture replenishment were rainfall amount and saturated hydraulic conductivity(Ks).These findings suggest that attention should be given to both vertical and lateral soil moisture replenishment,and the mid-slope position could be preferred for site selection to achieve precise and integrated forest-water management on hillslopes in semi-arid mountainous regions.展开更多
基金supported by the National Key Research and Development Program of China(2023YFF1203502)the National Natural Science Foundation of China(62171300,62301343,and 62394314)+1 种基金the Project of Cultivation for Young Top-Notch Talents of Beijing Municipal Institutions(BPHR202203109)the Capital Medical University Research and Development Fund(PYZ22027).
文摘The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment.Previous studies have suggested that there is an auditory“where”pathway in the cortex for processing sound locations.The neural activation in regions along this pathway encodes sound locations by opponent hemifield coding,in which each unilateral region is activated by sounds coming from the contralateral hemifield.However,it is still unclear how these regions interact with each other to form a unified representation of the auditory space.In the present study,we investigated whether functional connectivity in the auditory“where”pathway encoded sound locations during passive listening.Participants underwent functional magnetic resonance imaging while passively listening to sounds from five distinct horizontal locations(−90°,−45°,0°,45°,90°).We were able to decode sound locations from the functional connectivity patterns of the“where”pathway.Furthermore,we found that such neural representation of sound locations was primarily based on the coding of sound lateralization angles to the frontal midline.In addition,whole-brain analysis indicated that functional connectivity between occipital regions and the primary auditory cortex also encoded sound locations by lateralization angles.Overall,our results reveal a lateralization-angle-based representation of sound locations encoded by functional connectivity patterns,which could add on the activation-based opponent hemifield coding to provide a more precise representation of the auditory space.
基金supported by STI 2030-Major Projects(2021ZD0201500)the National Natural Science Foundation of China(31822024,31671172,and 32300881)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB32010300)the Scientifc Foundation of Institute of Psychology,Chinese Academy of Sciences(E1CX172005 and E1CX4725CX).
文摘Musical training can counteract age-related decline in speech perception in noisy environments.However,it remains unclear whether older non-musicians and musicians rely on functional compensation or functional preservation to counteract the adverse efects of aging.This study utilized resting-state functional connectivity(FC)to investigate functional lateralization,a fundamental organization feature,in older musicians(OM),older non-musicians(ONM),and young non-musicians(YNM).Results showed that OM outperformed ONM and achieved comparable performance to YNM in speech-in-noise and speech-in-speech tasks.ONM exhibited reduced lateralization than YNM in lateralization index(LI)of intrahemispheric FC(LI_intra)in the cingulo-opercular network(CON)and LI of interhemispheric heterotopic FC(LI_he)in the language network(LAN).Conversely,OM showed higher neural alignment to YNM(i.e.,a more similar lateralization pattern)compared to ONM in CON,LAN,frontoparietal network(FPN),dorsal attention network(DAN),and default mode network(DMN),indicating preservation of youth-like lateralization patterns due to musical experience.Furthermore,in ONM,stronger left-lateralized and lower alignment-to-young of LI_intra in the somatomotor network(SMN)and DAN and LI_he in DMN correlated with better speech performance,indicating a functional compensation mechanism.In contrast,stronger right-lateralized LI_intra in FPN and DAN and higher alignment-to-young of LI_he in LAN correlated with better performance in OM,suggesting a functional preservation mechanism.These fndings highlight the diferential roles of functional preservation and compensation of lateralization in speech perception in noise among elderly individuals with and without musical expertise,ofering insights into successful aging theories from the lens of functional lateralization and speech perception.
基金supported by the grants from the National Natural Science Foundation of China(No.31970422,No.31672305 and No.31372217 to Guangzhan Fang)the Key Research Project of Education Department of Sichuan Province(No.18ZA0321 to Yansu Liu)。
文摘Brain asymmetry for processing visual information is widespread in animals.However,it is still unknown how the complexity of the underlying neural network activities represents this asymmetrical pattern in the brain.In the present study,we investigated this complexity using the approximate entropy(ApEn)protocol for electroencephalogram(EEG)recordings from the forebrain and midbrain while the music frogs(Nidirana daunchina)attacked prey stimulus.The results showed that(1)more significant prey responses were evoked by the prey stimulus presented in the right visual field than that in the left visual field,consistent with the idea that right-eye preferences for predatory behaviors exist in animals including anurans;(2)in general,the ApEn value of the left hemisphere(especially the left mesencephalon)was greatest under various stimulus conditions,suggesting that visual lateralization could be reflected by the dynamics of underlying neural network activities and that the stable left-hemisphere dominance of EEG ApEn may play an important role in maintaining this brain asymmetry.
基金This work was supported by the Deutsche Forschungsgemeinschaft,Grant Number TO914/2-1 to J.T-D.
文摘Asymmetries in bilateral organisms attract a lot of curiosity given that they are conspicuous departures from the norm.They allow the investigation of the integration at different levels of biological organization.Here we study whether and how behavioral and asymmetrical anatomical traits coevolved and work together.We ask if asymmetry is determined locally for each trait or at a whole individual level in a species bearing conspicuous asymmetrical genitalia.Asymmetric genitalia evolved in many species;however,in most cases the direction of asymmetry is fixed.Therefore,it has been rarely determined if there is an association between the direction of asymmetry in genitalia and other traits.In onesided livebearer fish of the genus Jenynsia(Cyprinodontiformes,Anablepidae),the anal fin of males is modified into a gonopodium,an intromittent organ that serves to inseminate females.The gonopodium shows a conspicuous asymmetry,with its tip bending either to the left or the right.By surveying 13 natural populations of Jenynsia lineata,we found that both genital morphs are equally common in wild populations.In a series of experiments in a laboratory population,we discovered asymmetry and lateralization for multiple other traits;yet,the degree of integration varied highly among them.Lateralization in exploratory behavior in response to different stimuli was not associated with genital morphology.Interestingly,the direction of genital asymmetry was positively correlated with sidedness of mating preference and the number of neuromasts in the lateral line.This suggests integration of functionally linked asymmetric traits;however,there is no evidence that asymmetry is determined at the whole individual level in our study species.
文摘Functional asymmetries, for example, the preferential involvement of 1 brain hemisphere to process stimuli, may increase brain efficiency and the capacity to carry out tasks simultaneously. We investigated which hemisphere was primarily invoIved in processing acoustic stimuli in goats using a headorienting paradigm. Three playbacks using goat vocalizations recorded in different contexts: food anticipation (positive), isolation (negative), food frustration (negative), as well as 1 playback involving dog barks (negative) were presented on the left and right sides of the test subjects simultaneously. The head-orienting response (left or right) and latency to resume feeding were recorded. The direction of the head-orienting response did not differ between the various playbacks. However, when the head-orienting response was tested against chanee level, goats showed a right bias regardless of the stimuli presented. Goats responded more to dog barks than to food frustration calls, whereas responses to food anticipation and isolation calls were intermediate. In addition, the latency to resume feeding, an indicator of fear reaction, was not affected by the kind of vocalization presented. These results provide evidence for asymmetries in goat vocal perceptio n of emotional-li nked con specific and heterospecific calls. They also suggest involvement of the left brain hemisphere for processing acoustic stimuli, which might have been perceived as familiar and non -threate ning.
文摘BACKGROUND： Previous studies have analyzed cerebral activation and lateralization of cognitive functions, as well as cerebellar function with reference to high-level cognitive processing. However, there has been very little research on systematization and diversification. In particular, there are no reports on cerebellar lateralization, although reliable results have been reported on cerebral lateralization. OBJECTIVE： This study analyzed cerebellar activation and lateralization in relation to verbal and visuospatial tasks using functional magnetic resonance imaging （fMRI）. DESIGN, TIME AND SETTING： A block design for fMRI observation was performed at the fMRI Laboratory, Brain Science Research Center, Korea Advanced Institute of Science and Technology from May 2006 to September 2008. PARTICIPANTS： Sixteen healthy, male, college students, aged （23.3 ± 0.5） years, and 16 healthy, male, college students, aged （21.5 ± 2.3） years, participated in the study, respectively. METHODS： Verbal and visuospatial tasks were presented while functional brain images were acquired using a 3T fMRI system. Verbal analogy testing required the subject to select the word with the same relationship as one of the given words. Verbal antonym testing required the subject to select the word with a different meaning among four words. Visuospatial tasks involved selecting a shape that corresponded to a given figure with four examples, as well as selecting a development figure of a diagram. MAIN OUTCOME MEASURES： Changes in cerebellar activation and lateralization between two cognition tasks. RESULTS： Bilateral hemisphere Iobules VI and IX, right hemisphere Iobule VIII, bilateral hemisphere Iobules Crus I, and vermis Iobule IV, V, and Vl were closely related to verbal tasks in comparison to visuospatial tasks. Conversely, bilateral hemisphere Iobules IV and V, as well as the right hemisphere Iobule VI, were closely related to visuospatial tasks compared to verbal tasks. There was no great difference between the number of activated voxels in the cerebellums during the tasks, and cerebellar lateralization was not observed. CONCLUSION： In the cerebellum, the activation region, but not lateralization, was different between verbal and visuospatial tasks.
基金supported by the Russian Science Foundation(grant no.19-14-00119)The complex expeditions on Kolguev Island for wildfowl population monitoring were supported by Vogelschutz-Komitee and Conservation Bundesamt fur Naturschutz,BfN,(MEERESENTEN grant 3516821500).
文摘Behavioural lateralization,which reflects the functional specializations of the two brain hemispheres,is assumed to play an important role in cooperative intraspecific interactions.However,there are few studies focused on the lateralization in cooperative behaviours of individuals,especially in a natural setting.In the present study,we investigated Iateralized spatial interactions between the partners in life-long monogamous pairs.The male-female pairs of two geese species(barnacle,Branta leucopsis,and white-fronted,Anser albifrons geese),were observed during different stages of the annual cycle in a variety of conditions.In geese flocks,we recorded which visual hemifield(left/right)the following partner used to monitor the leading partner relevant to the type of behaviour and the disturbance factors.In a significant majority of pairs,the following bird viewed the leading partner with the left eye during routine behaviours such as resting and feeding in undisturbed conditions.This behavioural lateralization,implicating the right hemisphere processing,was consistent across the different aggregation sites and years of the study.In contrast,no significant bias was found in a variety of geese behaviours associated with enhanced disturbance(when alert on water,flying or fleeing away when disturbed,feeding during the hunting period,in urban area feeding and during moulting).We hypothesize that the increased demands for right hemisphere processing to deal with stressful and emergency situations may interfere with the manifestation of lateralization in social interactions.
文摘Lateralization of cognitive functions influences a large number of fitness-related behaviors and shows,in most species,substantial variation in strength and direction.Laboratory works and field data have suggested that this variation is often due to adaptive phenotypic plasticity.Strong lateralization should be favored in some ecological conditions,for example,under high risk of predation.For anuran tadpoles,the presence of cover affects predation risk,with tadpoles being more exposed to predators in environments with reduced cover.We tested the hypothesis that the amount of cover experienced early in life affects lateralization in the edible frog,Pelophylax escu-lentus,tadpoles.We exposed embryos and larvae to high or low vegetation cover environments.For half of the subjects,the treatment was constant whereas the remaining subjects were switched to the opposite treatment after hatching.In agreement with the theoretical expectation,tadpoles exposed to low vegetation cover for the entire development were more lateralized and showed a stronger alignment in directionality of lateralization compared with tadpoles exposed to high vege-tation cover.This indicates a possible role of natural variation in vegetation abundance and deve卜opmental plasticity as determinants of between-population and between-individual differences in lateralization.We also found that shifting from high to low vegetation cover treatments and vice versa disrupted lateralization alignment,suggesting that developmental trajectories for this trait are determined at the embryonic stage and need environmental stability to be fully expressed.
文摘Brain lateralization for language in high-functioning children with autism spectrum conditions (ASC) and sensory processing were explored as a part of a neuropsychological profile. A dichotic listening test and the Luria laterality subtest were administered to all participants (including controls) and the sensory profile test only to the ASC group. The usual right ear advantage was not exhibited by children with ASC and anomalies in auditory filtering were found. The sensory profile of 60% of the sample was characterized by hypersensitivity to auditory stimuli, hyposensitivity to vestibular information, high emotional reactions to sensory experiences, poor psychosocial coping strategies, high distractibility and inability to interpret body and facial language. Hyper-responsiveness to environmental auditory stimuli was significantly associated with impaired attention. Similarly, non-adaptive responses to sensory quotidian experiences were strongly connected to poor coping strategies. Our results, although preliminary, contribute to emphasizing the importance of including additional assessment methods such as the dichotic listening and the sensory profile questionnaire in the evaluation of cognitive profile in high-functioning children with ASC to plan an individualized psycho-educative intervention.
文摘The objective is to study changes in EEG time-domain Kolmogorov entropy and cortical lateralization of brain function areas during complex problem solving mental task in healthy human subjects. EEG data for healthy subjects are acquired during complex problem solving mental task using a net of 6 electrodes. The subject was given a nontrivial multiplication problem to solve and the signals were recorded for 10s during the task. Kolmogorov entropy values during the task were calculated. It was found that Kolmogorov entropy values were obviously greater in P4 channel (right) than ones in P3 channel (left) during complex problem solving task. It indicated that all subjects presented significant left parietal lateralization for the total frequency spectrum. These results suggest that it may be possible to noninvasively lateralize, and even eventually localize, cerebral regions essential for particular mental tasks from scalp EEG data.
文摘In recent decades, functional magnetic resonance imaging (fMRI) has proven to be more effective than the Wada test in the evaluation of language lateralization in special populations such as epileptic patients and children. However, fMRI requires that subjects remain motionless during data acquisition, making the assessment of receptive and expressive language difficult in young children and population with special needs. Near-Infrared spectroscopy (NIRS) is a non- invasive technique that has proven to be more tolerant to motion artifacts. The aim of the present study was to investigate the use of NIRS to assess receptive language patterns using a story listening paradigm. Four native French-speakers listened to stories read aloud by a bilingual speaker in both French and Arabic. To determine if the signal recorded was affected by episodic memory processes, a familiar story and an unknown story were presented. Results showed that listening to stories in French elicited a significantly higher left lateralized response than listening to stories in Arabic, independently of the familiarity of the story. These results confirm that NIRS is a useful non-invasive technique to assess receptive language in adults and can be used to investigate language lateralization among children and epileptic patients slated for epilepsy surgery.
文摘This study investigated the effect of transcranial direct current stimulation（t DCS） polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive tasks. Thirty healthy participants with no neurological disorders were recruited to participate in this study. Participants were randomly allocated into active or control condition. For the active condition, t DCS intensity was 2 m A with stimulation applied for 15 minutes to the right hemisphere（t DCS condition）. For the sham control, electrodes were placed in the same position, but the stimulator was turned off after 30 seconds（sham condition）. The tapping and tracking task tests were performed before and after for both conditions. Univariate analysis revealed significant difference only in the tracking task. For direct comparison of both tasks within each group, the tracking task had significantly higher Z score than the tapping task in the t DCS group（P 〈 0.05）. Thus, our study indicates that stimulation of the right hemisphere using t DCS can effectively improve visuomotor（tracking） task over simple repetitive（tapping） task.
文摘This paper reviews research on hemispheric lateralization.There are neurological evidences for the lateralization of speech and language functions and inter-and intrahemispherical differences between males and females.The results for the study of lateralization and bilingualism are mixed,proving the complexity and multidimensionality of lateralization.
基金supported by institutional funding from the Universitàdegli Studi di Milano(to D.R.),Universitàdegli Studi di Padova(to C.S.),and the Istituto Nazionale per la Protezione e la Ricerca Ambientale(ISPRA)(to J.G.C.).Nest-boxes were installed with support from the European Commission through the LIFE Project“Rapaci Lucani”(LIFE05NAT/IT/00009)and were designed by G.Ceccolini.
文摘Costs and benefits of brain lateralization may depend on environmental conditions.Growing evidence indicates that the development of brain functional asymmetries is adaptively shaped by the environmental conditions experienced during early life.Food availability early in life could act as a proxy of the environmental conditions encountered during adulthood,but its potential modulatory effect on lateralization has received little attention.We increased food supply from egg laying to early nestling rearing in a wild population of lesser kestrels Falco naumanni,a sexually dimorphic raptor,and quantified the lateralization of preening behavior(head turning direction).As more lateralized individuals may perform better in highly competitive contexts,we expected that extra food provisioning,by reducing the level of intra-brood competition for food,would reduce the strength of lateralization.We found that extra food provisioning improved nestling growth,but it did not significantly affect the strength or direction of nestling lateralization.In addition,maternal body condition did not explain variation in nestling lateralization.Independently of extra food provisioning,the direction of lateralization differed between the sexes,with female nestlings turning more often toward their right.Our findings indicate that early food availability does not modulate behavioral lateralization in a motor task,suggesting limited phenotypic plasticity in this trait.
文摘Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective degeneration of motor neurons in the brain,brainstem,and spinal cord,as well as abnormal protein deposition in the cytoplasm of neurons and glial cells.The biological markers under extensive scrutiny are predominantly located in the cerebrospinal fluid,blood,and even urine.Among these biomarke rs,neurofilament proteins and glial fibrillary acidic protein most accurately reflect the pathologic changes in the central nervous system,while creatinine and creatine kinase mainly indicate pathological alterations in the peripheral nerves and muscles.Neurofilament light chain levels serve as an indicator of neuronal axonal injury that remain stable throughout disease progression and are a promising diagnostic and prognostic biomarker with high specificity and sensitivity.However,there are challenges in using neurofilament light chain to diffe rentiate amyotrophic lateral sclerosis from other central nervous system diseases with axonal injury.Glial fibrillary acidic protein predominantly reflects the degree of neuronal demyelination and is linked to non-motor symptoms of amyotrophic lateral sclerosis such as cognitive impairment,oxygen saturation,and the glomerular filtration rate.TAR DNA-binding protein 43,a pathological protein associated with amyotrophic lateral sclerosis,is emerging as a promising biomarker,particularly with advancements in exosome-related research.Evidence is currently lacking for the value of creatinine and creatine kinase as diagnostic markers;however,they show potential in predicting disease prognosis.Despite the vigorous progress made in the identification of amyotrophic lateral sclerosis biomarkers in recent years,the quest for definitive diagnostic and prognostic biomarke rs remains a formidable challenge.This review summarizes the latest research achievements concerning blood biomarkers in amyotrophic lateral sclerosis that can provide a more direct basis for the differential diagnosis and prognostic assessment of the disease beyond a reliance on clinical manifestations and electromyography findings.
基金supported by INSERM.Shantou University and A French-Chinese Agreement(PRA B97-03 from the Association France-Chinese Pour-La Recherche Scientifique&Technique)the National Natural Science Foundation of China(#302712l1.#30371315)the Scientific and Developing Foundation of Shantou University(L0001l).
文摘The work is to explore the relationship between the levels of cytokines(IL-1β and IL-6)in C57BL/6J mice treated with MPTP and brain lateralization.By using paw preference test,right-pawed,left-pawed mice models were established.Following single injection of 1-methyl-4-phenyl-2,3,6-tetrahydropyrid(MPTP)(40 mg/kg)to impair dopaminergic neuron,enzyme linked immunosorbent assay(ELISA)kits were used for detection of plasma levels of cytokines.The results showed that in saline treated C57BL/6J mice(control),there was no obvious difference observed between left-pawed and right-pawed mice in plasma levels of IL-1β and IL-6.In MPTP treated mice,there was no difference between level of IL-1β in left-pawed mice and that in right-pawed ones in statistics,that is,they were increased on day 1 and day 3,but decreased on day 6.The plasma level of IL-6 was lower in left-pawed than that in right-pawed mice (p<0.005)after MPTP treatment. On day 1 and day 3,the level of IL-6 was almost the same as control;on day 6,it was significantly increased, higher than that of control(p<0.001)in left-pawed mice.While in right-pawed mice,on day 1 and day 3,it was no different from control,too.And on day 6,it significantly increased in compared with control(p<0.005).In conclusion,the level of plasma IL-6 of C57BL/6J mice treated with MPTP increased.The variation of IL-6 was correlated to brain lateralization.Cellular & Molecular Immunology.2004;1(3):219-223.
基金the National Natural Science Foundation of China(82471593 to J.M.32330047 and 31930057 to F.W.+2 种基金and 82071970 to Y.W.and 82072506 to Y.L.)the Science Fund for Distinguished Young Scholars of Hubei Province(2023AFA109 to Y.W.)Hubei Provincial Natural Science Foundation of China(2024AFB963 to Q.R.).
文摘The muscular system plays a critical role in the human body by governing skeletal movement,cardiovascular function,and the activities of digestive organs.Additionally,muscle tissues serve an endocrine function by secreting myogenic cytokines,thereby regulating metabolism throughout the entire body.Maintaining muscle function requires iron homeostasis.Recent studies suggest that disruptions in iron metabolism and ferroptosis,a form of iron-dependent cell death,are essential contributors to the progression of a wide range of muscle diseases and disorders,including sarcopenia,cardiomyopathy,and amyotrophic lateral sclerosis.Thus,a comprehensive overview of the mechanisms regulating iron metabolism and ferroptosis in these conditions is crucial for identifying potential therapeutic targets and developing new strategies for disease treatment and/or prevention.This review aims to summarize recent advances in understanding the molecular mechanisms underlying ferroptosis in the context of muscle injury,as well as associated muscle diseases and disorders.Moreover,we discuss potential targets within the ferroptosis pathway and possible strategies for managing muscle disorders.Finally,we shed new light on current limitations and future prospects for therapeutic interventions targeting ferroptosis.
基金National Natural Science Foundation of China(U24A20714 to XMF and 82102238 to PC)。
文摘BACKGROUND:Tracheal intubation(TI)is a fundamental procedure for securing the airway or assisting ventilation in emergency medicine.Tracheal intubation in the lateral position(TILP)has been utilized in clinical practice,demonstrating potential advantages in specific scenarios,including emergency settings.However,there is a lack of comprehensive reviews and practical protocols on TILP application.To address this gap,we performed a narrative review,and provided evidence-based recommendations to formulate a practice protocol,to assist clinicians to effectively apply TILP.METHODS:We conducted a narrative review of TILP applications and developed recommendations based on clinical research evidence and clinical experience.Delphi method was used among the TILP consortium to grade the strength of the recommendations and to help reach consensus.The practice protocols were formulated as warranted by advancements in medical knowledge,technology,and practice.RESULTS:This narrative review summarized the current evidence on TILP application,highlighting its safety,efficacy,challenges,and potential complications.In total,24 recommendations and a clinical protocol for TILP application in emergency patients were established.CONCLUSION:TILP is a valuable technique in emergency medicine.We reviewed its application in emergency settings and formulated recommendations along with a clinical practice protocol.Future studies are needed to evaluate the safety and efficacy of TILP,broaden its scope of application,and explore effective training protocols.
基金supported by the Natural Science Foundation of Heilongjiang Province(No.ZD2021E006)the National Natural Science Foundation of China(Nos.52174075 and 52074110).
文摘The models constructed by particle flow simulation method can effectively simulate the heterogeneous substance characteristics and failure behaviors of rocks.However,existing contact models overlook the rock cracks,and the various simulation methods that do consider cracks still exhibit certain limitations.In this paper,based on Flat-Joint model and Linear Parallel Bond model,a crack contact model considering linked substance in the crack is proposed by splitting the crack contact into two portions:linked portion and unlinked portion for calculation.The new contact model considers the influence of crack closure on the contact force-displacement law.And a better compressive tensile strength ratio(UCS/T)was obtained by limiting the failure of the contact bond to be solely controlled by the contact force and moment of the linked portion.Then,by employing the FISH Model tool within the Particle Flow Code,the contact model was constructed and verified through contact force–displacement experiments and loading-unloading tests with cracked model.Finally,the contact model was tested through simulations of rock mechanics experiments.The results indicate that the contact model can effectively simulate the axial and lateral strain laws of rocks simultaneously and has a relatively good reproduction of the bi-modularity of rocks.
基金financially supported by the Central Public-Interest Scientific Institution Basal Research Fund of Chinese Academy of Forestry(CAFYBB2021ZW002)the National Key Research and Development Program of China(2022YFF1300404)the National Natural Science Foundation of China(U21A2005)。
文摘Mountainous areas are the priority for forest restoration in semiarid regions,with hillslopes serving as the basic units of mountains.Precipitation is the only water source in these regions,and the uneven distribution of hillslope soil moisture replenishment after precipitation determines vegetation survival and growth.Therefore,in this study experiments were performed on a hillslope in the Liupan Mountains,Ningxia Hui Autonomous Region,China,to quantify the unevenness of soil moisture replenishment.Soil water content(SWC)in the 0–60 cm layer and precipitation were monitored throughout the growing season in 2020 and 2021.The results showed that(1)Annual soil moisture replenishment was the highest at the mid-slope position,with an average of 309.9 mm,especially under moderate and heavy rain grade conditions,reaching 38.7% and 30.8% of the total replenishment,respectively;(2)Vertical replenishment played a dominant role in the total replenishment,accounting for 82.8%;lateral replenishment played an important but lesser role,accounting for up to 17.2% of the total replenishment;(3)Based on a soil moisture replenishment model established in this study,the maximal replenishment occurred at 90 m from the top of the slope;(4)The dominant factors contributing to the soil moisture replenishment were rainfall amount and saturated hydraulic conductivity(Ks).These findings suggest that attention should be given to both vertical and lateral soil moisture replenishment,and the mid-slope position could be preferred for site selection to achieve precise and integrated forest-water management on hillslopes in semi-arid mountainous regions.
