Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh...Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior.展开更多
Iron is the most abundant transition metal in the brain and is essential for brain development and neuronal function;however,its abnormal accumulation is also implicated in various neurological disorders.The olfactory...Iron is the most abundant transition metal in the brain and is essential for brain development and neuronal function;however,its abnormal accumulation is also implicated in various neurological disorders.The olfactory bulb(OB),an early target in neurodegenerative diseases,acts as a gateway for environmental toxins and contains diverse neuronal populations with distinct roles.This study explored the cell-specific vulnerability to iron in the OB using a mouse model of intranasal administration of ferric ammonium citrate(FAC).Olfactory function was assessed through olfactory discrimination tests,while iron levels in OB tissues,cerebrospinal fluid(CSF),and serum were quantified using inductively coupled plasma mass spectrometry(ICP-MS),immunohistochemical staining,and iron assays.Transcriptomic changes and immune responses were assessed using RNA sequencing and immune cell infiltration analysis.Results showed that intranasal FAC administration impaired olfactory function,accompanied by iron deposition in the olfactory mucosa and OB,as well as damage to olfactory sensory neurons.Notably,these effects occurred without elevations in CSF or serum iron levels.OB iron accumulation activated multiple immune cells,including microglia and astrocytes,but did not trigger ferroptosis.Spatial transcriptomic sequencing of healthy adult mouse OBs revealed significant cellular heterogeneity,with an abundance of neuroglia and neurons.Among neurons,GABAergic neurons were the most prevalent,followed by glutamatergic and dopaminergic neurons,while cholinergic and serotonergic neurons were sparsely distributed.Under iron-stressed conditions,oligodendrocytes,dopaminergic neurons,and glutamatergic neurons exhibited significant damage,while GABAergic neurons remained unaffected.These findings highlight the selective vulnerability of neuronal and glial populations to iron-induced stress,offering novel insights into the loss of specific cell types in the OB during iron dysregulation.展开更多
Objective:This study assessed heat exposure,physiological responses,and the risk of chronic kidney disease among outdoor agricultural workers in Pak Chong,Thailand,and developed a predictive model for Wet Bulb Globe T...Objective:This study assessed heat exposure,physiological responses,and the risk of chronic kidney disease among outdoor agricultural workers in Pak Chong,Thailand,and developed a predictive model for Wet Bulb Globe Temperature(WBGT).Methods:A cross-sectional study was conducted among 170 agricultural workers.Field WBGT was measured at 33 locations in April and July and corrected for Clothing Adjustment Factor to determine effective WBGT.Core temperature,skin temperature,heart rate,blood pressure,and body weight were monitored before,during,and after work shifts.Urine dipstick and microalbumin tests were performed to evaluate dehydration and kidney disorder.Workloads were classified according to American Conference of Governmental Industrial Hygienists(ACGIH)metabolic rate categories.Meteorological data were used to train machine learning models—including linear regression,decision tree,random forest,and extreme gradient boosting—to predict WBGT values.Results:Effective WBGT at fruit gardens and field crops sites frequently exceeded ACGIH limits for moderateto-heavy work.Workers’systolic/diastolic blood pressure and heart rate increased during work(transient cardiovascular strain)while body temperature remained stable.Post-shift,34.7%showed moderate dehydration;microalbumin screening was positive in 31/170(18.2%)suggesting possible early renal involvement but not chronic kidney disease diagnosis.Among the predictive models,extreme gradient boosting achieved the best performance(root mean square error=0.798℃,mean absolute error=0.576℃,R^(2)=0.81).The most influential predictors were air temperature,sunshine duration,and site-specific factors.Conclusions:Agricultural workers in Pak Chong are frequently exposed to heat stress that exceeds ACGIH standards,predisposing them to dehydration and kidney impairment.The findings support evidence-based preventive strategies such as regulated work–rest cycles,hydration management,and medical surveillance.Moreover,the validated WBGT prediction tool offers a practical approach for real-time monitoring and proactive climate adaptation to protect outdoor workers in heat-prone environments.展开更多
A new natural product (1) together with 26 know compounds were isolated from the Bulbs of Ornithogalum caudatum. Their structures were established on the basis of spectral analyses as n-butyl pyroglutamate (1), nonade...A new natural product (1) together with 26 know compounds were isolated from the Bulbs of Ornithogalum caudatum. Their structures were established on the basis of spectral analyses as n-butyl pyroglutamate (1), nonadecyl alcohol(2), eicosanol(3), behenic acid(4), b-sitosterol(5), stigmasterol(6), glycerol 1-monocerotate(7), pyrocatechol(8), p-ethoxybenzoic acid(9), p-coumarinic acid(10), protocatechuric acid(11), ursolic acid(12), betulinic acid(13), fumaric acid(14), succinic acid(15), uracil(16), xanthine(17), quercetin(18), kaempferol (19), isorham-netin(20), adenosine(21), daucosterol(22), stigmasterol 3-O-b-D-glucopyranoside(23), quercetin 3-O-b-D-glucopyra-noside(24), kaempferol 3-O-b-D-glucopyranoside(25), rutin(26), and kaempferol 3-O-b-rutinoside(27). All of them, except compound 5, were isolated from this plant for the first time.展开更多
With different parts of bulb scale as explants, the proliferation method of Guizhou Lilium brownii were studied with 3% sodium hypochlorite and MS medium with different concentrations of hormones. The results show tha...With different parts of bulb scale as explants, the proliferation method of Guizhou Lilium brownii were studied with 3% sodium hypochlorite and MS medium with different concentrations of hormones. The results show that it is feasible to disinfect the bulbs of Lilium brownii with 3% sodium hypoehlorite, moreover, the sodium hypochlorite is very cheap and harmless to researchers, experimental materials and environment. MS + NAA 0.3 mg/L + 6-BA 1.5 mg/L is optimum for the induction of bulbs and, the basal part of Lilium brownie is the optimum explants. After culture for 25 d on the same medium, the tube bulbs could be obtained with the characteristics of high propagation coefficient, strong and new roots. The survival rate is over 90% for transplantation of tube bulbs with diameter between 1-2cm. The method developed in the present study can proliferate abundant Lilium brownii seedling in short time.展开更多
Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microe...Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microelectrode technique was used to record extracellular spontaneous electrical activities of olfactory bulb in B. gar-garizans. [Result] Along with the development of olfactory bulb, the discharge types increased gradual y. Single spontaneous firing enhanced gradual y and it reached the maximum in the metamorphosis phase. The intensity of consecutive single sponta-neous firing changed slightly at the middle of post-embryonic development, but it was stil higher than in the early phase and the adult phase. Consecutive burst spontaneous firing frequency went down over time. [Conclusion] Along with the de-velopment of olfactory bulb, the neuronal excitability increases step by step and the neuronal electrical activities diversify gradualy.展开更多
The purpose of this article is to detect sex and age difference in the structure of the olfactory bulb in dogs by histological methods. The thickness of the olfactory bulbs layers and its main cells were analyzed comp...The purpose of this article is to detect sex and age difference in the structure of the olfactory bulb in dogs by histological methods. The thickness of the olfactory bulbs layers and its main cells were analyzed comparatively with the methods of HE-staining and statistics, through which we studied the development course of dogs' olfactory bulb and the structural differences which affect the olfaction in both males and females. The results showed that between both male and female juveniles and adult males and females, the difference in thickness of each layer is not significant. But the difference in quantity of mitral cells between adult males and females was significant. Meanwhile, the structure of every layer in juvenile dogs was apparent while the volume and the weight of adult dogs' olfactory bulb and each layer's width increased significantly. On the other hand, the density of each layer's cells decreased apparently. Our results demonstrated that the olfactory bulb developed with age, and the apparent differences in morphology and quantity of mitral cells between males and females may be one of the reasons leading to the sexual variations of olfactory sensitivity.展开更多
[Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, ...[Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, Rodina and Constanta were cul- tured in media supplemented with different cytokinin and auxin at different concen- tration, and then the adventitious buds in each treatment were calculated. [Result] Cytokinins had different influence on the adventitious bud differentiation of the three oriental lily cultivars. Among them, 6-BA had the best effect to induce the adventi- tious bud differentiation from bulb scales of Tiber and Rodina, but there was some difference in the optimal concentration. KT had the best effect to induce the adven- titious bud differentiation of Constanta. The auxins had little influence on the quality of the adventitious bud of the three oriental lily cultivars, but caused some difference in differentiation coefficients. [Conclusion] The most suitable media for the adventi- tious bud differentiation from bulb scales in vitro of Tiber, Rodina and Constanta were MS+0.2 mg/L 6-BA+0.2 mg/L 2,4-D, MS+I.0 mg/L 6-BA+0.2 mg/L IAA, MS+ 1.0 mg/L KT+0.5 mg/L 2,4-D, respectively.展开更多
The main active components extracted from Panax notoginseng are total saponins. They have been shown to inhibit platelet aggregation, increase cerebral blood flow, improve neurological behavior, decrease infarct volum...The main active components extracted from Panax notoginseng are total saponins. They have been shown to inhibit platelet aggregation, increase cerebral blood flow, improve neurological behavior, decrease infarct volume and promote proliferation and differentiation of neural stem cells in the hippocampus and lateral ventricles. However, there is a lack of studies on whether total saponins of Panax notoginsertg have potential benefits on immature neuroblasts in the olfactory bulb following ischemia and reperfusion. This study established a rat model of global cerebral ischemia and reperfusion using four-vessel occlusion. Rats were administered total sa- ponins of Panax notoginseng at 75 mg/kg intraperitoneally 30 minutes after ischemia then once a day, for either 7 or 14 days. Total saponins of Panax notoginseng enhanced the number of dou- blecortin (DCX)+ neural progenitor ceils and increased co-localization of DCX with neuronal nuclei and phosphorylated cAMP response element-binding/DCX+ neural progenitor cells in the olfactory bulb at 7 and 14 days post ischemia. These findings indicate that following global brain ischemia/reperfusion, total saponins of Panax notoginseng promote differentiation of DCX+ cells expressing immature neuroblasts in the olfactory bulb and the underlying mechanism is related to the activation of the signaling pathway of cyclic adenosine monophosphate response element binding protein.展开更多
Sensory processing is strongly modulated by different brain and behavioral states,and this is based on the top-down modulation.In the olfactory system,local neural circuits in the olfactory bulb(OB)are innervated by c...Sensory processing is strongly modulated by different brain and behavioral states,and this is based on the top-down modulation.In the olfactory system,local neural circuits in the olfactory bulb(OB)are innervated by centrifugal afferents in order to regulate the processing of olfactory information in the OB under different behavioral states.The purpose of the present study was to explore the organization of neural networks in olfactory-related cortices and modulatory nuclei that give rise to direct and indirect innervations to the glomerular layer(GL)of the OB at the whole-brain scale.Injection of different recombinant attenuated neurotropic viruses into the GL showed that it received direct inputs from each layer in the OB,centrifugal inputs from the ipsilateralanterior olfactory nucleus(AON),anterior piriform cortex(Pir),and horizontal limb of diagonal band of Broca(HDB),and various indirect inputs from bilateral cortical neurons in the AON,Pir,amygdala,entorhinal cortex,hippocampus,HDB,dorsal raphe,median raphe and locus coeruleus.These results provide a circuitry basis that will help further understand the mechanism by which olfactory informationprocessing in the OB is regulated.展开更多
Hyperhomocysteinemia has been shown to be associated with neurodegenerative diseases; however, lesions or histological changes and mechanisms underlying homocysteine-induced injury in olfactory bulb neurons remain unc...Hyperhomocysteinemia has been shown to be associated with neurodegenerative diseases; however, lesions or histological changes and mechanisms underlying homocysteine-induced injury in olfactory bulb neurons remain unclear. In this study, hyperhomocysteinemia was induced in apolipoprotein E-deficient mice with 1.7% methionine. Pathological changes in the olfactory bulb were observed through hematoxylin-eosin and Pischingert staining. Cell apoptosis in the olfactory bulb was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining. Transmission electron microscopy revealed an abnormal ultrastructure of neurons. Furthermore, immunoreactivity and expression of the hairy enhancer of the split 1 (Hesl) and Hess were measured using immunohistochemistry, immunofluorescence, and western blot assay. Our results revealed no significant structural abnormality in the ol- factory bulb of hyperhomocysteinemic mice. However, the number of TUNEL-positive cells increased in the olfactory bulb, lipofuscin and vacuolization were visible in mitochondria, and the expression of Hes1 and Hes5 decreased. These findings confirm that hyperhomocyste- inemia induces injury in olfactory bulb neurons by downregulating Hes1 and Hes5 expression.展开更多
With the increasing demand for the clean sustainable power, the turbine design urgently turns to increase the capability significantly toward higher head for generating larger power. Currently, there are many studies ...With the increasing demand for the clean sustainable power, the turbine design urgently turns to increase the capability significantly toward higher head for generating larger power. Currently, there are many studies in the field of the bulb turbine with single-stage runner, though reports about counter-rotating tandem-runner are rare. However, the further high-head application with the single-stage runner is very difficult to achieve due to the limit of the specific speed. In this paper, a new bulb turbine with the tandem-runner is designed in order to substantially increase the applicable limit toward higher head with larger power. A half of the net head is absorbed by the frontal runner which can generate output power, while the remaining half is absorbed by the rear runner. To generate the Euler energy required for the rear runner, the frontal runner has the counter-rotation against the rear runner so that the counter-rotating tandem-runner can meet the purpose of double head and power under the same size as the conventional bulb turbine. Supply and demand of Euler energy between the two runners are thoroughly optimized through the detailed flow analysis, in order to secure the stable operation. As a result, the interference of Euler energies between the outflow from the frontal runner and the inflow to the rear runner is confirmed to be very small on the counter-rotating interface between the two runners. The prediction method of on-cam performance between the two adjustable runners is also developed numerically, which provides optimal flow between the two runners. This research provides a theoretical basis for the optimal design and operation of the counter-rotating tandem-runner bulb turbines.展开更多
Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the el...Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the electrophysiological characteristics of amphibian olfactory bulb in the period of hibernation and after hibernation and its effects on the start of hibernation and spontaneous awakening. The research showed four forms of spontaneous firings: single spontaneous firing, burst spontaneous firing, irregular spontaneous firing and consecutive single spontaneous firing. The single spontaneous firing includes slow depolarized spontaneous firing and fast depolarized spontaneous firing, and the slow depolarized spontaneous firing occurs only during the hibernation period. In hibernation, the low amplitude and low frequency firing with a longer duration may be relevant to maintaining the tonicity of the central nervous system in toads that are in hibernation, and this kind of firing may also provide an excited basis for their arousal from hibernation. After hibernation, the amplitude and frequency of firing increase, but the firing duration gets shorter. This form of short-term firing, which may be a phenomenon of sensory neurons fast adapting, is one of the neuronal mechanisms for the arousal of hibernating animals.展开更多
The olfactory receptor neurons lining the nasal cavity have a remarkable capacity to regenerate throughout life. They are replenished continuously and their axons make new connections within the olfactory bulb. Howeve...The olfactory receptor neurons lining the nasal cavity have a remarkable capacity to regenerate throughout life. They are replenished continuously and their axons make new connections within the olfactory bulb. However, some factors such as head trauma and skull base surgery damage the olfactory nerve which lead to olfactory dysfunction. Losing the sense of smell has considerable effects on quality of life and life-expectancy. Therefore, there is a clear need to find a treatment for olfactory dysfunction. One such potential treatment is growth factor therapy which showed promising results in the spinal cord and brain injuries. The aim of the present study was to investigate whether combined delivery of two growth factors, vascular endothelial growth factor and platelet-derived growth factor treatment can improve the olfactory neurons regeneration in mice. The degeneration of the olfactory neurons was induced by unilateral bulbectomy. The treatment group received 1.5 μg of the combined growth factors intranasally, while the control injured group received saline. Growth factor treatment significantly increased the number of immature neurons at 5 and 7 days post injury and also the number of mature olfactory neurons at 10 and 14 days post bulbectomy. Regenerating axons extended over a larger volume in the operated cavity in the treatment group compared to control group at 14 days post bulbectomy. The growth factor treatment also significantly reduced astrocytic glia scar in the operated cavity. The results indicate that the combined delivery of the growth factors has the potential to improve olfactory dysfunction.展开更多
The olfactory bulb(OB) is the first relay station in the olfactory system.In the OB,mitral/tufted cells(M/Ts),which are the main output neurons,play important roles in the processing and representation of odor informa...The olfactory bulb(OB) is the first relay station in the olfactory system.In the OB,mitral/tufted cells(M/Ts),which are the main output neurons,play important roles in the processing and representation of odor information.Recent studies focusing on the function of M/Ts at the single-cell level in awake behaving mice have demonstrated that odor-evoked firing of single M/Ts displays transient/long-term plasticity during learning.Here,we tested whether the neural activity of M/Ts and sniffing patterns are dependent on anticipation and reward in awake behaving mice.We used an odor discrimination task combined with in vivo electrophysiological recordings in awake,head-fixed mice,and found that,while learning induced plasticity of spikes and beta oscillations during odor sampling,we also found plasticity of spikes,beta oscillation,sniffing pattern,and coherence between sniffing and theta oscillations during the periods of anticipation and/or reward.These results indicate that the activity of M/Ts plays important roles not only in odor representation but also in salience-related events such as anticipation and reward.展开更多
Recently,botanical extracts are gaining popularity as biostimulants in vegetable production.In present study,the effect of aqueous garlic bulb extract(AGE)was studied on the growth and physiology of eggplant grown in ...Recently,botanical extracts are gaining popularity as biostimulants in vegetable production.In present study,the effect of aqueous garlic bulb extract(AGE)was studied on the growth and physiology of eggplant grown in plastic tunnel.AGE was foliage sprayed with various frequencies,i.e.,0,S1(once),S2(twice)and S3(three times)at two independent growth stages,pre-and post-transplant.The results showed that the treated plants exhibited stimulatory responses in growth and physiology in accord with the repetition of AGE spray and growth stages of the plants,respectively.A single foliage sprayed pre-transplant resulted in improved growth,i.e.,plant morphology and biomass,and enhanced antioxidants enzymes(superoxide dismutase,SOD;peroxidase,POD),photosynthesis and chlorophyll abundance observed at vegetative,first flowering and fruit setting stages,respectively.However,thrice application inhibited the plant growth and development and resulted in lipid peroxidation,i.e.,increased malondialdehyde(MDA)content.In addition,the post-transplant application also showed growth stimulation and interestingly,an overall positive influence was observed with respect to the AGE application and no significant increase in the MDA content indicated the post-transplant seedlings responded well.Our findings demonstrate that AGE can act as a biostimulant to enhance the eggplant growth in plastic tunnel production.展开更多
HadISDH.extremes is an annually updated global gridded monthly monitoring product of wet and dry bulb temperature–based extremes indices,from January 1973 to December 2022.Data quality,including spatial and temporal ...HadISDH.extremes is an annually updated global gridded monthly monitoring product of wet and dry bulb temperature–based extremes indices,from January 1973 to December 2022.Data quality,including spatial and temporal stability,is a key focus.The hourly data are quality controlled.Homogeneity is assessed on monthly means and used to score each gridbox according to its homogeneity rather than to apply adjustments.This enables user-specific screening for temporal stability and avoids errors from inferring adjustments from monthly means for the daily maximum values.For general use,a score(HQ Flag)of 0 to 6 is recommended.A range of indices are presented,aligning with existing standardised indices.Uniquely,provision of both wet and dry bulb indices allows exploration of heat event character—whether it is a“humid and hot”,“dry and hot”or“humid and warm”event.It is designed for analysis of long-term trends in regional features.HadISDH.extremes can be used to study local events,but given the greater vulnerability to errors of maximum compared to mean values,cross-validation with independent information is advised.展开更多
In this work, low-temperature vulcanized, transparent silane modified epoxy resins for LED filament bulb package were prepared. Firstly, transparent silane modified epoxy resins were produced through a controllable so...In this work, low-temperature vulcanized, transparent silane modified epoxy resins for LED filament bulb package were prepared. Firstly, transparent silane modified epoxy resins were produced through a controllable sol-gel method using γ-(2,3-epoxypropoxy)propytrimethoxysilane and dimethyldiethoxylsilane. The features of the reaction were investigated and the products were characterized in detail. Subsequently, various curing agents were explored to prepare transparent silane modified epoxy resins. The silane modified epoxy resins cured by PEA-230 at a fairly low temperature(40 °C/2 h then 60 °C/1 h) exhibited excellent thermal stability with a thermal degradation temperature as high as 316.5 °C and adjustable hardness between 40-60 shore A. The application tests showed the materials obtained were good candidates for LED filament bulb package.展开更多
Heat events may be humid or dry.While several indices incorporate humidity,such combined indices obscure identification and exploration of heat events by their different humidity characteristics.The new HadISDH.extrem...Heat events may be humid or dry.While several indices incorporate humidity,such combined indices obscure identification and exploration of heat events by their different humidity characteristics.The new HadISDH.extremes global gridded monitoring product uniquely provides a range of wet and dry bulb temperature extremes indices.Analysis of this new data product demonstrates its value as a tool for quantifying exposure to humid verses dry heat events.It also enables exploration into“stealth heat events”,where humidity is high,perhaps enough to affect productivity and health,while temperature remains moderate.Such events may not typically be identified as“heat events”by temperature-focused heat indices.Over 1973-2022,the peak magnitude of humid extremes(maximum daily wet bulb temperature over a month;T_(w)X)for the global annual mean increased significantly at 0.13±0.04℃(10 yr)^(−1),which is slightly slower than the global annual mean T_(w) increase of 0.22±0.04℃(10 yr)^(−1).The frequency of moderate humid extreme events per year(90th per-centile daily maxima wet bulb temperature exceedance;T_(w)X90p)also increased significantly at 4.61±1.07 d yr^(−1)(10 yr)^(−1).These rates were slower than for temperature extremes,TX and TX90p,which respectively increased significantly at 0.27±0.04℃(10 yr)^(−1) and 5.53±0.72 d yr^(−1)(10 yr)^(−1).Similarly,for the UK/Europe focus region,JJA-mean T_(w)X increased significantly,again at a slower rate than for TX and mean T_(w).HadISDH.extremes shows some evidence of“stealth heat events”occurring where humidity is high but temperature remains more moderate.展开更多
The ultra-structure of mother and outer daughter scales of Lilium Oriental hybrid Sorbonne were studied using transmission electron microscope to examine the sub-cellular localization of starch and lipid droplets duri...The ultra-structure of mother and outer daughter scales of Lilium Oriental hybrid Sorbonne were studied using transmission electron microscope to examine the sub-cellular localization of starch and lipid droplets during growth and development from shoot emergence to senescence.The contents of starch granules and lipid droplets in the cell of the mother scales decreased significantly from shoot emergence to anthesis,indicating that these scales served as a source for growth and development.After flowering,the number of starch granules and lipid droplets increased dramatically,and finally the cells were filled with the above molecules indicating that the bulb becomes a major sink during bulb enlargement.Ultrastructure observation also showed that symplastic pathway is the main pathway in cells in the exchange and transportation of material during bulb development.The activity of β-amylase,one of the key enzymes catalyzing starch breakdown,showed a similar trend.The enzyme sub-cellular localization via immune-gold electron-microscopy showed that βamylase was predominantly located together with starch granules,while the gold particles were scarcely found in other sub-cellular compartments.The result suggested that this enzyme is compartmented together with its functional substrate supporting its function in catalyzing starch breakdown in living plant cells.展开更多
文摘Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior.
基金supported by the National Natural Science Foundation of China (32471188,32170984,82301787)。
文摘Iron is the most abundant transition metal in the brain and is essential for brain development and neuronal function;however,its abnormal accumulation is also implicated in various neurological disorders.The olfactory bulb(OB),an early target in neurodegenerative diseases,acts as a gateway for environmental toxins and contains diverse neuronal populations with distinct roles.This study explored the cell-specific vulnerability to iron in the OB using a mouse model of intranasal administration of ferric ammonium citrate(FAC).Olfactory function was assessed through olfactory discrimination tests,while iron levels in OB tissues,cerebrospinal fluid(CSF),and serum were quantified using inductively coupled plasma mass spectrometry(ICP-MS),immunohistochemical staining,and iron assays.Transcriptomic changes and immune responses were assessed using RNA sequencing and immune cell infiltration analysis.Results showed that intranasal FAC administration impaired olfactory function,accompanied by iron deposition in the olfactory mucosa and OB,as well as damage to olfactory sensory neurons.Notably,these effects occurred without elevations in CSF or serum iron levels.OB iron accumulation activated multiple immune cells,including microglia and astrocytes,but did not trigger ferroptosis.Spatial transcriptomic sequencing of healthy adult mouse OBs revealed significant cellular heterogeneity,with an abundance of neuroglia and neurons.Among neurons,GABAergic neurons were the most prevalent,followed by glutamatergic and dopaminergic neurons,while cholinergic and serotonergic neurons were sparsely distributed.Under iron-stressed conditions,oligodendrocytes,dopaminergic neurons,and glutamatergic neurons exhibited significant damage,while GABAergic neurons remained unaffected.These findings highlight the selective vulnerability of neuronal and glial populations to iron-induced stress,offering novel insights into the loss of specific cell types in the OB during iron dysregulation.
基金supported by Suranaree University of Technology,the National Science,Research and Innovation Fundthe Program Management Unit for Human Resources&Institutional Development,Research and Innovation,Fiscal Year 2024.
文摘Objective:This study assessed heat exposure,physiological responses,and the risk of chronic kidney disease among outdoor agricultural workers in Pak Chong,Thailand,and developed a predictive model for Wet Bulb Globe Temperature(WBGT).Methods:A cross-sectional study was conducted among 170 agricultural workers.Field WBGT was measured at 33 locations in April and July and corrected for Clothing Adjustment Factor to determine effective WBGT.Core temperature,skin temperature,heart rate,blood pressure,and body weight were monitored before,during,and after work shifts.Urine dipstick and microalbumin tests were performed to evaluate dehydration and kidney disorder.Workloads were classified according to American Conference of Governmental Industrial Hygienists(ACGIH)metabolic rate categories.Meteorological data were used to train machine learning models—including linear regression,decision tree,random forest,and extreme gradient boosting—to predict WBGT values.Results:Effective WBGT at fruit gardens and field crops sites frequently exceeded ACGIH limits for moderateto-heavy work.Workers’systolic/diastolic blood pressure and heart rate increased during work(transient cardiovascular strain)while body temperature remained stable.Post-shift,34.7%showed moderate dehydration;microalbumin screening was positive in 31/170(18.2%)suggesting possible early renal involvement but not chronic kidney disease diagnosis.Among the predictive models,extreme gradient boosting achieved the best performance(root mean square error=0.798℃,mean absolute error=0.576℃,R^(2)=0.81).The most influential predictors were air temperature,sunshine duration,and site-specific factors.Conclusions:Agricultural workers in Pak Chong are frequently exposed to heat stress that exceeds ACGIH standards,predisposing them to dehydration and kidney impairment.The findings support evidence-based preventive strategies such as regulated work–rest cycles,hydration management,and medical surveillance.Moreover,the validated WBGT prediction tool offers a practical approach for real-time monitoring and proactive climate adaptation to protect outdoor workers in heat-prone environments.
基金This work was supported by the Ministry of Science and Technology of China (96-901-05-266).
文摘A new natural product (1) together with 26 know compounds were isolated from the Bulbs of Ornithogalum caudatum. Their structures were established on the basis of spectral analyses as n-butyl pyroglutamate (1), nonadecyl alcohol(2), eicosanol(3), behenic acid(4), b-sitosterol(5), stigmasterol(6), glycerol 1-monocerotate(7), pyrocatechol(8), p-ethoxybenzoic acid(9), p-coumarinic acid(10), protocatechuric acid(11), ursolic acid(12), betulinic acid(13), fumaric acid(14), succinic acid(15), uracil(16), xanthine(17), quercetin(18), kaempferol (19), isorham-netin(20), adenosine(21), daucosterol(22), stigmasterol 3-O-b-D-glucopyranoside(23), quercetin 3-O-b-D-glucopyra-noside(24), kaempferol 3-O-b-D-glucopyranoside(25), rutin(26), and kaempferol 3-O-b-rutinoside(27). All of them, except compound 5, were isolated from this plant for the first time.
基金Supported by the Nomarch Funds for Excellent Science and Technology Teachers of Guizhou Province(S2004-17)the Special Foundation for Im-proving Scientific Research Condition of Guizhou Province(Q2005-4)the Doctor Startup of Guiyang Medical College(C2005-6)~~
文摘With different parts of bulb scale as explants, the proliferation method of Guizhou Lilium brownii were studied with 3% sodium hypochlorite and MS medium with different concentrations of hormones. The results show that it is feasible to disinfect the bulbs of Lilium brownii with 3% sodium hypoehlorite, moreover, the sodium hypochlorite is very cheap and harmless to researchers, experimental materials and environment. MS + NAA 0.3 mg/L + 6-BA 1.5 mg/L is optimum for the induction of bulbs and, the basal part of Lilium brownie is the optimum explants. After culture for 25 d on the same medium, the tube bulbs could be obtained with the characteristics of high propagation coefficient, strong and new roots. The survival rate is over 90% for transplantation of tube bulbs with diameter between 1-2cm. The method developed in the present study can proliferate abundant Lilium brownii seedling in short time.
基金Supported by grants from the Liaoning Provincial Department of Education(2011196)the Experimental Center Director Fund of Shenyang Normal University(sy201003)~~
文摘Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microelectrode technique was used to record extracellular spontaneous electrical activities of olfactory bulb in B. gar-garizans. [Result] Along with the development of olfactory bulb, the discharge types increased gradual y. Single spontaneous firing enhanced gradual y and it reached the maximum in the metamorphosis phase. The intensity of consecutive single sponta-neous firing changed slightly at the middle of post-embryonic development, but it was stil higher than in the early phase and the adult phase. Consecutive burst spontaneous firing frequency went down over time. [Conclusion] Along with the de-velopment of olfactory bulb, the neuronal excitability increases step by step and the neuronal electrical activities diversify gradualy.
基金National Natural Science Foundation of China (30370218)Shan-dong Science Fund for Distinguished Young Scholars(2005BS02005)Science Foundation for Excellent Scholars of Ministry of Education of China (NCET-07-0507)
文摘The purpose of this article is to detect sex and age difference in the structure of the olfactory bulb in dogs by histological methods. The thickness of the olfactory bulbs layers and its main cells were analyzed comparatively with the methods of HE-staining and statistics, through which we studied the development course of dogs' olfactory bulb and the structural differences which affect the olfaction in both males and females. The results showed that between both male and female juveniles and adult males and females, the difference in thickness of each layer is not significant. But the difference in quantity of mitral cells between adult males and females was significant. Meanwhile, the structure of every layer in juvenile dogs was apparent while the volume and the weight of adult dogs' olfactory bulb and each layer's width increased significantly. On the other hand, the density of each layer's cells decreased apparently. Our results demonstrated that the olfactory bulb developed with age, and the apparent differences in morphology and quantity of mitral cells between males and females may be one of the reasons leading to the sexual variations of olfactory sensitivity.
基金Supported by Special Fund for the Dominant Subjects Development of the Higher Education Institutions of Jiangsu ProvinceScience and Technology Innovation Fund of Nanjing Forestry University(X09-120-4)~~
文摘[Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, Rodina and Constanta were cul- tured in media supplemented with different cytokinin and auxin at different concen- tration, and then the adventitious buds in each treatment were calculated. [Result] Cytokinins had different influence on the adventitious bud differentiation of the three oriental lily cultivars. Among them, 6-BA had the best effect to induce the adventi- tious bud differentiation from bulb scales of Tiber and Rodina, but there was some difference in the optimal concentration. KT had the best effect to induce the adven- titious bud differentiation of Constanta. The auxins had little influence on the quality of the adventitious bud of the three oriental lily cultivars, but caused some difference in differentiation coefficients. [Conclusion] The most suitable media for the adventi- tious bud differentiation from bulb scales in vitro of Tiber, Rodina and Constanta were MS+0.2 mg/L 6-BA+0.2 mg/L 2,4-D, MS+I.0 mg/L 6-BA+0.2 mg/L IAA, MS+ 1.0 mg/L KT+0.5 mg/L 2,4-D, respectively.
基金supported by the Hunan Provincial Innovation Foundation for Postgraduate in China,No.CX2014B099(to XH)the Science Foundation of Hunan Provincial Education Department of China,No.11C1264(to FJD),13C958(to XH)
文摘The main active components extracted from Panax notoginseng are total saponins. They have been shown to inhibit platelet aggregation, increase cerebral blood flow, improve neurological behavior, decrease infarct volume and promote proliferation and differentiation of neural stem cells in the hippocampus and lateral ventricles. However, there is a lack of studies on whether total saponins of Panax notoginsertg have potential benefits on immature neuroblasts in the olfactory bulb following ischemia and reperfusion. This study established a rat model of global cerebral ischemia and reperfusion using four-vessel occlusion. Rats were administered total sa- ponins of Panax notoginseng at 75 mg/kg intraperitoneally 30 minutes after ischemia then once a day, for either 7 or 14 days. Total saponins of Panax notoginseng enhanced the number of dou- blecortin (DCX)+ neural progenitor ceils and increased co-localization of DCX with neuronal nuclei and phosphorylated cAMP response element-binding/DCX+ neural progenitor cells in the olfactory bulb at 7 and 14 days post ischemia. These findings indicate that following global brain ischemia/reperfusion, total saponins of Panax notoginseng promote differentiation of DCX+ cells expressing immature neuroblasts in the olfactory bulb and the underlying mechanism is related to the activation of the signaling pathway of cyclic adenosine monophosphate response element binding protein.
基金supported by grants from the National Natural Science Foundation of China (31400946, 31671120, 31771197, 31329001, 31771156, 91632303, and 81661148053/H09)the Strategic Priority Research Program of Chinese Academy of Science (XDB32030200)the National Basic Research Development Program (973 Program) of China (2015CB755600)
文摘Sensory processing is strongly modulated by different brain and behavioral states,and this is based on the top-down modulation.In the olfactory system,local neural circuits in the olfactory bulb(OB)are innervated by centrifugal afferents in order to regulate the processing of olfactory information in the OB under different behavioral states.The purpose of the present study was to explore the organization of neural networks in olfactory-related cortices and modulatory nuclei that give rise to direct and indirect innervations to the glomerular layer(GL)of the OB at the whole-brain scale.Injection of different recombinant attenuated neurotropic viruses into the GL showed that it received direct inputs from each layer in the OB,centrifugal inputs from the ipsilateralanterior olfactory nucleus(AON),anterior piriform cortex(Pir),and horizontal limb of diagonal band of Broca(HDB),and various indirect inputs from bilateral cortical neurons in the AON,Pir,amygdala,entorhinal cortex,hippocampus,HDB,dorsal raphe,median raphe and locus coeruleus.These results provide a circuitry basis that will help further understand the mechanism by which olfactory informationprocessing in the OB is regulated.
基金supported by the National Natural Science Foundation of China,No.81560084,81560208a grant from the Project of Superior Discipline Groups in Ningxia Medical University of China,No.XY201414
文摘Hyperhomocysteinemia has been shown to be associated with neurodegenerative diseases; however, lesions or histological changes and mechanisms underlying homocysteine-induced injury in olfactory bulb neurons remain unclear. In this study, hyperhomocysteinemia was induced in apolipoprotein E-deficient mice with 1.7% methionine. Pathological changes in the olfactory bulb were observed through hematoxylin-eosin and Pischingert staining. Cell apoptosis in the olfactory bulb was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining. Transmission electron microscopy revealed an abnormal ultrastructure of neurons. Furthermore, immunoreactivity and expression of the hairy enhancer of the split 1 (Hesl) and Hess were measured using immunohistochemistry, immunofluorescence, and western blot assay. Our results revealed no significant structural abnormality in the ol- factory bulb of hyperhomocysteinemic mice. However, the number of TUNEL-positive cells increased in the olfactory bulb, lipofuscin and vacuolization were visible in mitochondria, and the expression of Hes1 and Hes5 decreased. These findings confirm that hyperhomocyste- inemia induces injury in olfactory bulb neurons by downregulating Hes1 and Hes5 expression.
基金supported by National Natural Science Foundation of China (Grant Nos. 50879026, 50679027)
文摘With the increasing demand for the clean sustainable power, the turbine design urgently turns to increase the capability significantly toward higher head for generating larger power. Currently, there are many studies in the field of the bulb turbine with single-stage runner, though reports about counter-rotating tandem-runner are rare. However, the further high-head application with the single-stage runner is very difficult to achieve due to the limit of the specific speed. In this paper, a new bulb turbine with the tandem-runner is designed in order to substantially increase the applicable limit toward higher head with larger power. A half of the net head is absorbed by the frontal runner which can generate output power, while the remaining half is absorbed by the rear runner. To generate the Euler energy required for the rear runner, the frontal runner has the counter-rotation against the rear runner so that the counter-rotating tandem-runner can meet the purpose of double head and power under the same size as the conventional bulb turbine. Supply and demand of Euler energy between the two runners are thoroughly optimized through the detailed flow analysis, in order to secure the stable operation. As a result, the interference of Euler energies between the outflow from the frontal runner and the inflow to the rear runner is confirmed to be very small on the counter-rotating interface between the two runners. The prediction method of on-cam performance between the two adjustable runners is also developed numerically, which provides optimal flow between the two runners. This research provides a theoretical basis for the optimal design and operation of the counter-rotating tandem-runner bulb turbines.
基金Liaoning Provincial Department of Education-Funded Project, No. 20068040the Experimental Center of Shenyang Normal University Foundation, No. 2008007
文摘Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the electrophysiological characteristics of amphibian olfactory bulb in the period of hibernation and after hibernation and its effects on the start of hibernation and spontaneous awakening. The research showed four forms of spontaneous firings: single spontaneous firing, burst spontaneous firing, irregular spontaneous firing and consecutive single spontaneous firing. The single spontaneous firing includes slow depolarized spontaneous firing and fast depolarized spontaneous firing, and the slow depolarized spontaneous firing occurs only during the hibernation period. In hibernation, the low amplitude and low frequency firing with a longer duration may be relevant to maintaining the tonicity of the central nervous system in toads that are in hibernation, and this kind of firing may also provide an excited basis for their arousal from hibernation. After hibernation, the amplitude and frequency of firing increase, but the firing duration gets shorter. This form of short-term firing, which may be a phenomenon of sensory neurons fast adapting, is one of the neuronal mechanisms for the arousal of hibernating animals.
基金supported by Queensland University of Technology Start Up Grant(to FC)a grant from the Clem Jones Foundation(to JASJ)
文摘The olfactory receptor neurons lining the nasal cavity have a remarkable capacity to regenerate throughout life. They are replenished continuously and their axons make new connections within the olfactory bulb. However, some factors such as head trauma and skull base surgery damage the olfactory nerve which lead to olfactory dysfunction. Losing the sense of smell has considerable effects on quality of life and life-expectancy. Therefore, there is a clear need to find a treatment for olfactory dysfunction. One such potential treatment is growth factor therapy which showed promising results in the spinal cord and brain injuries. The aim of the present study was to investigate whether combined delivery of two growth factors, vascular endothelial growth factor and platelet-derived growth factor treatment can improve the olfactory neurons regeneration in mice. The degeneration of the olfactory neurons was induced by unilateral bulbectomy. The treatment group received 1.5 μg of the combined growth factors intranasally, while the control injured group received saline. Growth factor treatment significantly increased the number of immature neurons at 5 and 7 days post injury and also the number of mature olfactory neurons at 10 and 14 days post bulbectomy. Regenerating axons extended over a larger volume in the operated cavity in the treatment group compared to control group at 14 days post bulbectomy. The growth factor treatment also significantly reduced astrocytic glia scar in the operated cavity. The results indicate that the combined delivery of the growth factors has the potential to improve olfactory dysfunction.
基金supported by the National Natural Science Foundation of China (31571082,31872771 and 31700895)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(16KJA180007)the Natural Science Foundation of Jiangsu Province (BK20170260)。
文摘The olfactory bulb(OB) is the first relay station in the olfactory system.In the OB,mitral/tufted cells(M/Ts),which are the main output neurons,play important roles in the processing and representation of odor information.Recent studies focusing on the function of M/Ts at the single-cell level in awake behaving mice have demonstrated that odor-evoked firing of single M/Ts displays transient/long-term plasticity during learning.Here,we tested whether the neural activity of M/Ts and sniffing patterns are dependent on anticipation and reward in awake behaving mice.We used an odor discrimination task combined with in vivo electrophysiological recordings in awake,head-fixed mice,and found that,while learning induced plasticity of spikes and beta oscillations during odor sampling,we also found plasticity of spikes,beta oscillation,sniffing pattern,and coherence between sniffing and theta oscillations during the periods of anticipation and/or reward.These results indicate that the activity of M/Ts plays important roles not only in odor representation but also in salience-related events such as anticipation and reward.
基金funded by the Shaanxi Provincial Science and Technology Innovation Project of China(2016KTCL02-01)
文摘Recently,botanical extracts are gaining popularity as biostimulants in vegetable production.In present study,the effect of aqueous garlic bulb extract(AGE)was studied on the growth and physiology of eggplant grown in plastic tunnel.AGE was foliage sprayed with various frequencies,i.e.,0,S1(once),S2(twice)and S3(three times)at two independent growth stages,pre-and post-transplant.The results showed that the treated plants exhibited stimulatory responses in growth and physiology in accord with the repetition of AGE spray and growth stages of the plants,respectively.A single foliage sprayed pre-transplant resulted in improved growth,i.e.,plant morphology and biomass,and enhanced antioxidants enzymes(superoxide dismutase,SOD;peroxidase,POD),photosynthesis and chlorophyll abundance observed at vegetative,first flowering and fruit setting stages,respectively.However,thrice application inhibited the plant growth and development and resulted in lipid peroxidation,i.e.,increased malondialdehyde(MDA)content.In addition,the post-transplant application also showed growth stimulation and interestingly,an overall positive influence was observed with respect to the AGE application and no significant increase in the MDA content indicated the post-transplant seedlings responded well.Our findings demonstrate that AGE can act as a biostimulant to enhance the eggplant growth in plastic tunnel production.
基金supported by the UK–China Research & Innovation Partnership Fund through the Met Office Climate Science for Service Partnership (CSSP) China as part of the Newton Fund
文摘HadISDH.extremes is an annually updated global gridded monthly monitoring product of wet and dry bulb temperature–based extremes indices,from January 1973 to December 2022.Data quality,including spatial and temporal stability,is a key focus.The hourly data are quality controlled.Homogeneity is assessed on monthly means and used to score each gridbox according to its homogeneity rather than to apply adjustments.This enables user-specific screening for temporal stability and avoids errors from inferring adjustments from monthly means for the daily maximum values.For general use,a score(HQ Flag)of 0 to 6 is recommended.A range of indices are presented,aligning with existing standardised indices.Uniquely,provision of both wet and dry bulb indices allows exploration of heat event character—whether it is a“humid and hot”,“dry and hot”or“humid and warm”event.It is designed for analysis of long-term trends in regional features.HadISDH.extremes can be used to study local events,but given the greater vulnerability to errors of maximum compared to mean values,cross-validation with independent information is advised.
基金financial support from the Zhejiang Provincial Natural Science Foundation of China (No.Y14E030008)the Commonweal Technology Application Research Project of Zhejiang Province (No.2013C31079)
文摘In this work, low-temperature vulcanized, transparent silane modified epoxy resins for LED filament bulb package were prepared. Firstly, transparent silane modified epoxy resins were produced through a controllable sol-gel method using γ-(2,3-epoxypropoxy)propytrimethoxysilane and dimethyldiethoxylsilane. The features of the reaction were investigated and the products were characterized in detail. Subsequently, various curing agents were explored to prepare transparent silane modified epoxy resins. The silane modified epoxy resins cured by PEA-230 at a fairly low temperature(40 °C/2 h then 60 °C/1 h) exhibited excellent thermal stability with a thermal degradation temperature as high as 316.5 °C and adjustable hardness between 40-60 shore A. The application tests showed the materials obtained were good candidates for LED filament bulb package.
基金supported by the UK–China Research & Innovation Partnership Fund through the Met Office Climate Science for Service Partnership (CSSP) China as part of the Newton Fund
文摘Heat events may be humid or dry.While several indices incorporate humidity,such combined indices obscure identification and exploration of heat events by their different humidity characteristics.The new HadISDH.extremes global gridded monitoring product uniquely provides a range of wet and dry bulb temperature extremes indices.Analysis of this new data product demonstrates its value as a tool for quantifying exposure to humid verses dry heat events.It also enables exploration into“stealth heat events”,where humidity is high,perhaps enough to affect productivity and health,while temperature remains moderate.Such events may not typically be identified as“heat events”by temperature-focused heat indices.Over 1973-2022,the peak magnitude of humid extremes(maximum daily wet bulb temperature over a month;T_(w)X)for the global annual mean increased significantly at 0.13±0.04℃(10 yr)^(−1),which is slightly slower than the global annual mean T_(w) increase of 0.22±0.04℃(10 yr)^(−1).The frequency of moderate humid extreme events per year(90th per-centile daily maxima wet bulb temperature exceedance;T_(w)X90p)also increased significantly at 4.61±1.07 d yr^(−1)(10 yr)^(−1).These rates were slower than for temperature extremes,TX and TX90p,which respectively increased significantly at 0.27±0.04℃(10 yr)^(−1) and 5.53±0.72 d yr^(−1)(10 yr)^(−1).Similarly,for the UK/Europe focus region,JJA-mean T_(w)X increased significantly,again at a slower rate than for TX and mean T_(w).HadISDH.extremes shows some evidence of“stealth heat events”occurring where humidity is high but temperature remains more moderate.
基金supported by the National Natural Science Foundation of China(31071815)the National HighTech R&D Program of China(2011AA100208)
文摘The ultra-structure of mother and outer daughter scales of Lilium Oriental hybrid Sorbonne were studied using transmission electron microscope to examine the sub-cellular localization of starch and lipid droplets during growth and development from shoot emergence to senescence.The contents of starch granules and lipid droplets in the cell of the mother scales decreased significantly from shoot emergence to anthesis,indicating that these scales served as a source for growth and development.After flowering,the number of starch granules and lipid droplets increased dramatically,and finally the cells were filled with the above molecules indicating that the bulb becomes a major sink during bulb enlargement.Ultrastructure observation also showed that symplastic pathway is the main pathway in cells in the exchange and transportation of material during bulb development.The activity of β-amylase,one of the key enzymes catalyzing starch breakdown,showed a similar trend.The enzyme sub-cellular localization via immune-gold electron-microscopy showed that βamylase was predominantly located together with starch granules,while the gold particles were scarcely found in other sub-cellular compartments.The result suggested that this enzyme is compartmented together with its functional substrate supporting its function in catalyzing starch breakdown in living plant cells.