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BODIPY 493 acts as a bright buffering fluorogenic probe for super-resolution imaging of lipid droplet dynamics

Chinese Chemical Letters 2022年第12期33卷 5042-5046页

作者： Jie Chen Wenjuan Liu Xiangning Fang Qinglong Qiao Zhaochao Xu CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

The need for temporal resolution and long-term stability in super-resolution fluorescence imaging has motivated research to improve the photostability of fluorescent probes.Due to the inevitable photobleaching of fluorophores,it is difficult to obtain long-term super-resolution imaging regardless of the self-healing strategy of introducing peroxide scavengers or the strategy of fluorophore structure modification to suppress TICT formation.The buffered fluorogenic probe uses the intact probes in the buffer pool to continuously replace the photobleached ones in the target,which greatly improves the photostability and enables stable dynamic super-resolution imaging for a long time.But the buffering capacity comes at the expense of reducing the number of fluorescent probes in targets,resulting in low staining fluorescence intensity.In this paper,we selected BODIPY 493,a lipid droplet probe with high fluorescence brightness,to explore the dynamic process of lipid droplet staining of this probe in cells.We found that BODIPY 493 only needs very low laser power for lipid droplet imaging due to the high molecular accumulation in lipid droplets and the high brightness,and the spatiotemporal resolution is greatly improved.More importantly,we found that BODIPY 493 also has a certain buffering capacity,which enables BODIPY 493 to be used for super-resolution imaging of lipid droplet dynamics.This work reminds researchers to coordinate the buffering capacity and brightness of fluorogenic probes.

关键词： Lipid droplet Super-resolution imaging Fluorescent probe Brightness buffering

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I/O Acceleration via Multi-Tiered Data buffering and Prefetching

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Journal of Computer Science & Technology 2020年第1期35卷 92-120页

作者： Anthony Kougkas Hariharan Devarajan Xian-He Sun Department of Computer Science Illinois Institute of TechnologyChicago 60616U.S.A

Modern High-Performance Computing(HPC)systems are adding extra layers to the memory and storage hierarchy,named deep memory and storage hierarchy(DMSH),to increase I/O performance.New hardware technologies,such as NVMe and SSD,have been introduced in burst buffer installations to reduce the pressure for external storage and boost the burstiness of modern I/O systems.The DMSH has demonstrated its strength and potential in practice.However,each layer of DMSH is an independent heterogeneous system and data movement among more layers is significantly more complex even without considering heterogeneity.How to efficiently utilize the DMSH is a subject of research facing the HPC community.Further,accessing data with a high-throughput and low-latency is more imperative than ever.Data prefetching is a well-known technique for hiding read latency by requesting data before it is needed to move it from a high-latency medium(e.g.,disk)to a low-latency one(e.g.,main memory).However,existing solutions do not consider the new deep memory and storage hierarchy and also suffer from under-utilization of prefetching resources and unnecessary evictions.Additionally,existing approaches implement a client-pull model where understanding the application's I/O behavior drives prefetching decisions.Moving towards exascale,where machines run multiple applications concurrently by accessing files in a workflow,a more data-centric approach resolves challenges such as cache pollution and redundancy.In this paper,we present the design and implementation of Hermes:a new,heterogeneous-aware,multi-tiered,dynamic,and distributed I/O buffering system.Hermes enables,manages,supervises,and,in some sense,extends I/O buffering to fully integrate into the DMSH.We introduce three novel data placement policies to efficiently utilize all layers and we present three novel techniques to perform memory,metadata,and communication management in hierarchical buffering systems.Additionally,we demonstrate the benefits of a truly hierarchical data prefetcher that ado

关键词： I/O buffering heterogeneous buffering layered buffering deep memory hierarchy burst buffers hierarchical data prefetching data-centric architecture

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A STUDY ON buffering CAPACITY OF THE FOREST SOIL AGAINST ACIDIC PRECIPITATION IN SEVERAL AREAS OF CHINA

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Chinese Geographical Science 1992年第2期2卷 32-38页

作者：林国珍廖柏寒丁茹 Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100083 PRC

Soil samples from several forest areas in China were analyzed by X-ray powder diffractometry after mineral separation and enrichment. The density gradient separation method with sequential extraction by acetone-methylene iodide mixtures was applied for the separation of fine sand fraction of soil samples. The clay fraction (buffering capacity against acidic precipitation were discussed.

关键词： forest soil mineral component acidic precipitation buffering capacity weathering potentiality

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Astrocytic modulation of potassium under seizures

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Neural Regeneration Research 2020年第6期15卷 980-987页

作者： Fushun Wang Xiaoming Qi Jun Zhang Jason HHuang Department of Neurosurgery Baylor Scott&White HealthTempleTXUSA Institute of Brain and Psychological Science Sichuan Normal UniversityChengduSichuan ProvinceChina Department of Neurosurgery PLA General HospitalBeijingChina Department of Surgery Texas A&M University College of MedicineTempleTXUSA

The contribution of an impaired astrocytic K^+ regulation system to epileptic neuronal hyperexcitability has been increasingly recognized in the last decade.A defective K^+ regulation leads to an elevated extracellular K^+ concentration([K^+]o).When[K^+]o reaches peaks of 10-12 mM,it is strongly associated with seizure initiation during hypersynchronous neuronal activities.On the other hand,reactive astrocytes during a seizure attack restrict influx of K^+ across the membrane both passively and actively.In addition to decreased K^+ buffering,aberrant Ca^2+ signaling and declined glutamate transport have also been observed in astrogliosis in epileptic specimens,precipitating an increased neuronal discharge and induction of seizures.This review aims to provide an overview of experimental findings that implicated astrocytic modulation of extracellular K^+ in the mechanism of epileptogenesis.

关键词： AQP4 Ca^2+ signaling cell volume connexins epilepsy K^+ buffering mi RNA NKCC pannexin TBI

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Lead removal from aqueous solution by employing natural brucite

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Journal of University of Science and Technology Beijing 2004年第5期11卷 394-397页

作者： LeiShao JiwenFu YueZhou JianfengChen ShouciLu ResearchCenteroftheMinistryofEducationforHighGravityEngineeringandTechnology CollegeofChemicalEngineeringBeijingUniversityofChemicalTechnologyBeijing100029China CivilandEnvironmentalEngineeringSchool UniversityofScienceandTechnologyBeijingBeijing100083China

The effect and mechanism of the removal of Pb^(2+) from an aqueous solutionby using brucite as the adsorbent were studied. It was revealed that the increase in pH of brucitesuspension, as a result of the release of magnesium hydroxide into the suspension, leads to a sharprise of the adsorption amount of Pb^(2+) on brucite. The synergism of buffering and adsorptioncapacities of brucite is responsible for the removal of Pb^(2+) from the aqueous solution. Thecoexistence of Cu^(2+) with Pb^(2+) causes a decrease of their adsorption on brucite due to acompetition for surface sites and brucite exhibits a higher adsorption capacity for Pb^(2+) than forCu^(2+). The percentage adsorption of Pb^(2+) on brucite could reach 96.38 percent, 97.20 percentand 94.09 percent respectively with the initial pH of the suspension pH_i = 1.76 (initial Pb^(2+)concentration [Pb^(2+)]_i = 20 mumol/L), 1.82 ([Pb^(2+)]_i = 100 mumol/L) and 1.84 ([Pb^(2+)]_i =500 mumol/L). It was concluded that brucite is a very efficient mineral adsorbent for Pb^(2+)removal from polluted acidic water.

关键词： lead ions brucite buffering adsorption removal

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Functional and molecular mechanism of intracellular pH regulation in human inducible pluripotent stem cells

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World Journal of Stem Cells 2018年第12期10卷 196-211页

作者： Shih-Chi Chao Gwo-Jang Wu Shu-Fu Huang Niann-Tzyy Dai Hsu-Kai Huang Mei-Fang Chou Yi-Ting Tsai Shiao-Pieng Lee Shih-Hurng Loh Graduate Institute of Life Sciences National Defense Medical Center Department of Obstetrics and Gynecology TriService General Hospital National Defense Medical Center Department of Pharmacy Practice Tri-Service General Hospital National Defense Medical Center Division of Plastic and Reconstructive Surgery Department of Surgery Tri-Service General Hospital National Defense Medical Center Division of Chest Surgery Department of Surgery Tri-Service General Hospital National Defense Medical Center Graduate Institute of Medical Sciences National Defense Medical Center Division of Cardiovascular Surgery Department of Surgery Tri-Service General Hospital National Defense Medical Center Division of Oral and Maxillofacial Surgery Department of Dentistry School of Dentistry Tri-Service General Hospital and National Defense Medical Center Department of Pharmacology National Defense Medical Center

AIM To establish a functional and molecular model of the intracellular pH(pH_i) regulatory mechanism in human induced pluripotent stem cells(hiPSCs).METHODS hiP SCs(HPS0077) were kindly provided by Dr. Dai from the Tri-Service General Hospital(IRB No. B-106-09). Changes in the pH_i were detected either by microspectrofluorimetry or by a multimode reader with a pH-sensitive fluorescent probe, BCECF, and the fluorescent ratio was calibrated by the high K^+/nigericin method. NH_4Cl and Na-acetate prepulse techniques were used to induce rapid intracellular acidosis and alkalization, respectively. The buffering power(β) was calculated from the ΔpH_i induced by perfusing different concentrations of(NH_4)_2SO_4. Western blot techniques and immunocytochemistry staining were used to detect the protein expression of pH_i regulators and pluripotency markers.RESULTS In this study, our results indicated that(1) the steadystate pH_i value was found to be 7.5 ± 0.01(n = 20) and 7.68 ± 0.01(n =20) in HEPES and 5% CO_2/HCO_3^- buffered systems, respectively, which were much greater than that in normal adult cells(7.2);(2) in a CO_2/HCO_3^--buffered system, the values of total intracellular buffering power(β) can be described by the following equation: β_(tot) = 107.79(pH_i)~2-1522.2(pH_i) + 5396.9(correlation coefficient R^2 = 0.85), in the estimated pH_i range of 7.1- 8.0;(3) the Na^+/H^+ exchanger(NHE) and the Na^+/HCO_3^- cotransporter(NBC) were found to be functionally activated for acid extrusion for pHi values less than 7.5 and 7.68, respectively;(4) V-ATPase and some other unknown Na^+-independent acid extruder(s) could only be functionally detected for pHi values less than 7.1;(5) the Cl^-/OH^- exchanger(CHE) and the Cl^- /HCO_3 anion exchanger(AE) were found to be responsible for the weakening of intracellular proton loading;(6) besides the CHE and the AE, a Cl^--independent acid loading mechanism was functionally identified; and(7) in hiPSCs, a strong positive correlation was observed between the loss of pluripotency an

关键词： microspectrofluorimetry human induced pluripotent stem cells Na^+/H^+exchanger Na^+/HCO3^-cotransporter Cl^-/OH^-exchanger Cl^-/HCO3^-exchanger V-ATPase intracellular buffering power intracellular pH BCECF

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Understanding the biochar’s role in ameliorating soil acidity

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Journal of Integrative Agriculture 2019年第7期18卷 1508-1517页

作者： SHI Ren-yong LI Jiu-yu NI Ni XU Ren-kou State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008P.R.China Nanjing Institute of Environmental Science Ministry of Ecology and EnvironmentNanjing 210042P.R. China Key Laboratory of Pesticide Environmental Assessment and Pollution Control Ministry of Ecology and EnvironmentNanjing 210042P.R.China

Extensive acidic soils,which suffer from accelerated soil acidification,are found in southern China.Soil acidity,aluminum toxicity,and nutrient deficiencies severely limited crop productivity in acidic soils.It has been widely reported that crop residue biochars can ameliorate acidic soils and increase crop productivity.Here,we summarized the positive effects and mechanisms involved in the correction of soil acidity,the alleviation of aluminum toxicity and the increase of soil pH buffering capacity by crop residue biochars.The carbonate,oxygen-containing functional groups and silicates in biochars are the major components responsible for their efficacy in amending acidic soils and resisting soil re-acidification.We conclude that application of crop residue biochars may be a better option than traditional liming to ameliorate acidic soils.Nonetheless,further researches into soil acidification are still required to address some issues that are controversial and poorly understood.

关键词： aluminum toxicity crop residue biochars pH buffering capacity soil acidity

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Suppressive effects of saliva against enamel demineralization caused by acid beverages

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Health 2011年第12期3卷 742-747页

作者： Shoji Takahashi Shigeru Watanabe Takashi Ogihara Koji Watanabe Kun Xuan Xiaojing Wang 不详

This study aimed to clarify the ability of the buffer systems of saliva to inhibit enamel demineralization after intake of an acid beverage. In the first experiment, titrable acidity tests were carried out. Ten milliliters of saliva stimulated by chewing gum base was obtained from 10 healthy adult subjects and the pH of each saliva sample was measured. The beverages used for the experiment were a carbonated soft drink (pH 2.2), a sports drink (pH 3.5), and 100% orange juice (pH 3.8). Distilled water adjusted to the pH of each saliva sample was used as a control. In the second experiment, the suppressive ability of saliva against enamel demineralization was quantitatively analyzed using quantitative light- induced fluorescence (QLF). Aliquots of stimulated saliva obtained from a subject were mixed with 15 ml of 100% orange juice in saliva:orange juice ratios of 1/30, 1/15, 1/10 and 1/5, and bovine teeth were soaked for 24 hours in the solutions. The △Q of the QLF analyses of the enamel was then measured. The lowest titrant volume which reduced the pH of the initial saliva (7.7 on average) to pH 5.4 was that of the orange juice. No relationship was found between the buffer capacity and the pH of the acid beverages. From the QLF measurement, the saliva-orange juice group showed a significantly decreased amount of enamel demineralization (p < 0.01 at 20% level) compared with the distilled water-orange juice group. In conclusion, saliva acts as a buffer to suppress enamel demineralization caused by low-pH beverages.

关键词： Erosion Acid Beverage Saliva buffering Capacity QLF

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BUFFER DIMENSIONING FOR RATE-BASED CONTROL IN ATM NETWORK

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Journal of Shanghai Jiaotong university(Science) 1997年第2期2卷 80-85页

作者：唐俊华顾尚杰诸鸿文

ＢＵＦＦＥＲＤＩＭＥＮＳＩＯＮＩＮＧＦＯＲＲＡＴＥ┐ＢＡＳＥＤＣＯＮＴＲＯＬＩＮＡＴＭＮＥＴＷＯＲＫＴａｎｇＪｕｎｈｕａ（唐俊华）ＴｅｔｓｕｙａＴａｋｉｎｅ＊ＧｕＳｈａｎｇｊｉｅ（顾尚杰）ＺｈｕＨｏｎｇｗｅｎ（诸鸿文... 详细信息

ＢＵＦＦＥＲＤＩＭＥＮＳＩＯＮＩＮＧＦＯＲＲＡＴＥ┐ＢＡＳＥＤＣＯＮＴＲＯＬＩＮＡＴＭＮＥＴＷＯＲＫＴａｎｇＪｕｎｈｕａ（唐俊华）ＴｅｔｓｕｙａＴａｋｉｎｅ＊ＧｕＳｈａｎｇｊｉｅ（顾尚杰）ＺｈｕＨｏｎｇｗｅｎ（诸鸿文）（Ｄｅｐｔ．ｏｆＥｌｅｃｔｒｏｎ...

关键词： ATM (asynchronous transfer mode) ABR(available bit rate) buffering flow control

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Structural Controls on the Geochemistry and Output of the Wells in the Olkaria Geothermal Field of the Kenyan Rift Valley

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International Journal of Geosciences 2016年第11期7卷 1299-1309页

作者： Ruth N. Wamalwa Christopher M. Nyamai Willis J. Ambusso Josephat Mulwa Aaron K. Waswa Kenya Electricity Generating Company—KenGen Naivasha Kenya Department of Geology University of Nairobi Nairobi Kenya School of Pure and Applied Sciences Kenyatta University Nairobi Kenya

The Olkaria geothermal field is located in the Kenya Rift valley, about 120 km from Nairobi. Geothermal activity is widespread in this rift with 14 major geothermal prospects being identified. Structures in the Greater Olkaria volcanic complex include: the ring structure, the Ol’Njorowa gorge, the ENE-WSW Olkaria fault and N-S, NNE-SSW, NW-SE and WNW-ESE trending faults. The faults are more prominent in the East, Northeast and West Olkaria fields but are scarce in the Olkaria Domes area, possibly due to the thick pyroclastics cover. The NW-SE and WNW- ESE faults are thought to be the oldest and are associated with the development of the rift. The most prominent of these faults is the Gorge Farm fault, which bounds the geothermal fields in the northeastern part and extends to the Olkaria Domes area. The most recent structures are the N-S and the NNE-SSW faults. The geochemistry and output of the wells cut by these faults have a distinct characteristic that is the N-S, NW-SE and WNW-ESE faults are characterized by wells that have high Cl contents, temperatures and are good producers whereas the NE-SW faults, the Ring Structure and the Ol’Njorowa gorge appear to carry cool dilute waters with less chloride concentration and thus low performing wells. Though the impacts of these faults are apparent, there exists a gap in knowledge on how wide is the impact of these faults on the chemistry and performance of the wells. This paper therefore seeks to bridge this gap by analysis of the chemical trends of both old wells and newly drilled ones to evaluate the impacts of individual faults and then using buffering technique of ArcGis estimate how far and wide the influence of the faults is. The data was obtained after the sampling and analysis of discharge fluids of wells located on six profiles along the structures cutting through the field. Steam samples were collected with a stainless steel Webre separator connected between the wellhead and an atmospheric silencer on the discharging wells whereas the analysis was done in h

关键词： Structural Controls Geochemistry Productivity buffering Olkaria Geothermal Field Kenya

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