Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but a...Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from coal.Here,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium looping.For comparison,a coal-to-acetylene process was also established by using coal as feedstock.The carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically analyzed.Moreover,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) furnace.Even though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA process.With sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA process.This work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier.展开更多
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H...The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas.展开更多
Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability o...Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability or dysfunction may be the key stimulating factors to activate NLRP3 inflammasome,and sustained Ca^(2+)transfer can result in mitochondrial dysfunction.We focused on KCs to explore the damage to mitochondria by EA.After EA stimulation,cells produced an oxidative stress(OS)response with a significant increase in ROS release.Immunoprecipitation experiments and the addition of inhibitors revealed that the increase in the level of intracellular Ca^(2+)led to Ca^(2+)accumulation in the mitochondrial matrix via mitochondria-associated membranes(MAMs).This was accompanied by a significant release of m ROS,loss of MMP and ATP,and a significant increase in mitochondrial permeability transition pore opening,ultimately leading to mitochondrial instability.These findings confirmed the mechanism that EA induced mitochondrial Ca^(2+)imbalance in KCs via MAM,ultimately leading to mitochondrial dysfunction.Meanwhile,EA induced OS and the decrease of MMP and ATP in rat liver,and significant lesions were found in liver mitochondria.Swelling of the inner mitochondrial cristae and mitochondrial vacuolization occurred,with a marked increase in lipid droplets.展开更多
Plant calmodulins(CaMs)and calmodulin-like proteins(CMLs)mediate Ca~(2+)signaling in response to abiotic stresses.Manipulation of this signaling in crops could increase stress tolerance.We review methods for detecting...Plant calmodulins(CaMs)and calmodulin-like proteins(CMLs)mediate Ca~(2+)signaling in response to abiotic stresses.Manipulation of this signaling in crops could increase stress tolerance.We review methods for detecting Ca~(2+)signals,regulatory roles of Ca Ms and CMLs,binding targets,and Ca~(2+)networks under abiotic stress in organelles.展开更多
The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorat...The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorating postmenopausal osteoporosis in a rat model established using bilateral ovariectomy.After 3 months of FM(containing vitamin D,and casein phosphopeptides,1000 mg Ca/100 g)or control milk(110 mg Ca/100 g milk)supplementation,bone changes were assessed using dual-energy X-ray absorptiometry,microcomputed tomography,and bone biomechanical testing.The results revealed that FM can regulate bone metabolism and gut microbiota composition,which act on bone metabolism through pathways associated with steroid hormone biosynthesis,relaxin signaling,serotonergic synapse,and unsaturated fatty acid biosynthesis.Furthermore,FM administration significantly increased bone mineral content and density in the lumbar spine and femur,as well as femoral compressive strength,while improving femoral trabecular bone parameters and microarchitecture.Mechanistically,we found that the effects may be due to increased levels of estrogen,bone formation marker osteocalcin,and procollagen typeⅠN-propeptide,and decreased expression of the bone resorption marker C-telopiptide and tartrate-resistant acid phosphatase 5b.Overall,the findings suggest that FM is a potential alternative therapeutic option for ameliorating postmenopausal osteoporosis.展开更多
Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffe...Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffer from slow reaction kinetics,poor stability,and low solar absorptance.Here,we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability,mechanical strength,and solar absorptance via Al–Mn–Fe oxides.The energy storage density of proposed CaCO_(3)pellets is still as high as 1455 kJ kg^(-1)with only a slight decay rate of 4.91%over 100 cycles,which is higher than that of state-of-the-art pellets in the literature,in stark contrast to 69.9%of pure CaCO_(3)pellets over 35 cycles.Compared with pure CaCO_(3),the energy storage power density or decomposition rate is improved by 120%due to lower activation energy and promotion of Ca^(2+)diffusion by binary sulfate.The energy release or carbonation rate rises by 10%because of high O^(2-)transport ability of molten binary sulfate.Benefiting from fast energy storage/release rate and high solar absorptance,thermochemical energy storage efficiency is enhanced by more than 50%under direct solar irradiation.This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate,high energy density,good cyclic stability,and high solar absorptance simultaneously.展开更多
Introduction: COVID-19 vaccine uptake and acceptance have been a major global concern due to the prevalent misinformation and disinformation that has characterized the vaccine rollout worldwide. This study aimed to as...Introduction: COVID-19 vaccine uptake and acceptance have been a major global concern due to the prevalent misinformation and disinformation that has characterized the vaccine rollout worldwide. This study aimed to assess COVID-19 vaccine uptake and acceptance, and associated factors among selected community members in two states in southwestern Nigeria. Method: We conducted a cross-sectional study using a multistage sampling technique. Fifty catchment settlements of 10 health facilities in each of Oyo and Ogun States targeted for a COVID-19 infection prevention and control intervention were randomly selected. Four households were targeted per settlement. All households that refused access were replaced, to ensure a minimum of four households randomly selected per settlement. The primary household decision-maker was interviewed in each household. Information elicited included respondents’ sociodemographic characteristics, health history, knowledge, risk and benefit perception about the COVID-19 vaccine, vaccine uptake, and willingness to be vaccinated. The study was conducted from July–August 2021. Data were analyzed using SPSS IBM version 23. Result: Four hundred household decision-makers were surveyed in Oyo and Ogun states, after replacement. The mean age of the respondents was 43.0 ± 11.0 years. The majority, 346 (86.5%) had heard about COVID-19 vaccination, but only 47 (13.6%) had received a COVID-19 vaccination. Of the 299 respondents who reported not receiving a COVID-19 vaccination, 166 (55.5%) were willing to be vaccinated. In univariate analysis, respondents who were female had tertiary education, perceived that COVID-19 vaccines are free and accessible, perceived that COVID-19 vaccines have minimal side effects, and perceived higher benefits of COVID-19 vaccination had higher odds of being vaccinated. In contrast, younger respondents, respondents with higher knowledge scores on COVID-19 preventive measures, and with chronic illness had lower likelihoods of being vaccinated. In multivariate analysis, only the respondent’s age, perception score on COVID-19 vaccine benefits, knowledge score on IPC measures, and positive response on accessibility and safety were significant after adjusting for other factors. Conclusion: COVID-19 vaccine uptake rate as well as willingness to receive vaccination were low in the study setting. There is an urgent need for policymakers to embark on well-designed campaigns to address barriers to COVID-19 vaccination to increase vaccine uptake.展开更多
Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline ...Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline metal ions, specifically calcium ions, of the de-oiled PW were removed by precipitation with sodium carbonate to give access to pure sodium chloride as industrial salt from the remaining PW. While the purity of the precipitated calcium carbonate (CaCO3) depends on the precipitation conditions, CaCO3 of up to 95.48% purity can be obtained, which makes it a salable product. The precipitation of CaCO3 decreases the amount of calcium ions in PW from 11,300 ppm to 84 ppm.展开更多
Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and t...Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic strength.However,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP nanospheres.Furthermore,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like crystals.These results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.展开更多
Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed ...Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed in this work.This innovative process raised the fluor-ite’s grade to 97.26wt%while producing nanoscale calcium carbonate from its leachate,which contained plenty of calcium ions.On the production of nanoscale calcium carbonate,the impacts of concentration,temperature,and titration rate were examined.By modifying the process conditions and utilizing crystal conditioning agents,calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511μm were produced.The influence of the impurity ions Mn^(2+),Mg^(2+),and Fe^(3+)was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride solution.The combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources,thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles.展开更多
The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally le...The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interaction partners, and the physiological and pathophysiological role of the NECAB family.展开更多
The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressib...The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressibility of Ca(N_(3))_(2)changed as the pressure increased,and no phase transition occurred within the pressure from ambient pressure up to 54 GPa.The measured zero-pressure bulk modulus of Ca(N_(3))_(2)is higher than that of other alkali metal azides,due to differences in the ionic character of their metal-azide bonds.Using CASTEP,all vibration modes of Ca(N_(3))_(2)were accurately identified in the vibrational spectrum at ambient pressure.In the high-pressure vibration study,several external modes(ext.)and internal bending modes(ν_(2))of azide anions(N_(3)^(-))softened up to~7 GPa and then hardened beyond that pressure.This evidence is consistent with the variation observed in the F_(E)–f_(E)data analyzed from the XRD result,where the slope of the curve changes at 7.1 GPa.The main behaviors under pressure are the alternating compression,rotation,and bending of N_(3)^(-)ions.The bending behavior makes the structure of Ca(N_(3))_(2)more stable under pressure.展开更多
Introduction: Pregnant women are a highly vulnerable population for COVID-19 with increased risk of hospitalization, intensive-care unit admission, invasive ventilation support, and mortality. Objective: This study de...Introduction: Pregnant women are a highly vulnerable population for COVID-19 with increased risk of hospitalization, intensive-care unit admission, invasive ventilation support, and mortality. Objective: This study determined the socio-demographic and economic factors associated with the uptake of COVID-19 vaccine among pregnant women utilizing antenatal care services in Pumwani Maternity Hospital, Nairobi County-Kenya. Methods: The study was carried out from 15 June to 23 July 2023. Systematic sampling was used to select 302 women from whom data was collected through face-to-face interviews using a pre-tested semi-structured questionnaire. Data was analyzed using SPSS software in which bivariate and multivariate logistic regression analyses were done at a significance level of p Results: A total of 302 pregnant women participated in the study. Of these, 105 (34.8%) were aged between twenty-six (26) and thirty (30) years. The mean age of the women was 28.60 ± (SD = 5.297). The uptake of the COVID-19 vaccine was 41.1%. The common side effects reported to be associated with the vaccines were fever, headache, joint pain, vomiting and skin rash. Uptake of the COVID-19 vaccine was significantly associated with being married (AOR = 3.65, 95% CI: 0.62 - 1.80, p = 0.001), having a secondary level of education (AOR = 3.78, 95% CI: 0.99 - 2.88, p = 0.001) and being employed (COR = 2.66, 95% CI: 1.31 - 3.06, p = 0.001). Conclusion: COVID-19 vaccination uptake remains low among pregnant women in seeking ANC in Nairobi. The individual factors associated with the uptake of COVID-19 vaccine among pregnant Women at Pumwani maternity hospital in Nairobi County were being married, having secondary level of education and being employed. Integration of the COVID-19 vaccine with other routine vaccinations as per the national immunization program in Kenya and the enhancement of education regarding the safety and efficacy of the COVID-19 vaccine in pregnancy and breastfeeding and economic empowerment of women are recommended.展开更多
Extracellular vesicles(EVs)are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity,natural functionality,and excellent biocompatibility.However,limitations ...Extracellular vesicles(EVs)are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity,natural functionality,and excellent biocompatibility.However,limitations such as low uptake efficiency,insufficient production,and inhomogeneous performance undermine their potential.To address these issues,numerous researchers have put forward various methods and applications for enhancing EV uptake in recent decades.In this review,we introduce various methods for the cellular uptake of EVs and summarize recent advances on the methods and mechanisms for enhancing EV uptake.In addition,we provide further understanding regarding enhancing EV uptake and put forward prospects and challenges for the development of EV-based therapy in the future.展开更多
The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementi...The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementitious material. The composite system of calcium carbonate and aluminate minerals is studied by measuring the component of hydration products, the hydration heat, setting time and compressive strength.The results prove that the composite system has certain cementitious properties and is feasible to prepare new low-carbon cement.展开更多
Background: Chronic venous insufficiency (CVI) describes a condition that affects the venous system of the lower extremities due to venous hypertension (VH. The prevalence is between 5% - 30%. CVI is associated with o...Background: Chronic venous insufficiency (CVI) describes a condition that affects the venous system of the lower extremities due to venous hypertension (VH. The prevalence is between 5% - 30%. CVI is associated with older age, smoking, lower extremity trauma, presence of an arteriovenous shunt, and elevated estrogen levels. All patients should be initially treated with conservative management. Venoactive drugs like calcium dobesilate are useful. Objectives: The primary objective compared the clinical improvement in patients with CVI, grades 0 - 3 of the CEAP classification of chronic venous disease, produced by two formulations of calcium dobesilate: calcium dobesilate LP 1 g OD vs calcium dobesilate 500 mg BID, immediate release. The secondary objective assessed the side effects of both formulations. Method: All patients took one tablet and one capsule at 7 am, and one capsule at 7 pm, for 8 weeks. One group received dobesilate 1 g OD and the other group received dobesilate 500 md BID. They were evaluated after 15, 30 and 60 days of treatment, using the symptom evaluation scale. Results: In both groups, there was a significant decrease in the symptom score after 15 days. Four patients in the Dobesilate OD group: had adverse effects, which did not require suspension of treatment. In the BID dobesilate group, there was one therapeutic failure, and one case of gastric discomfort. Conclusions: Prolonged-release Calcium dobesilate 1 g OD is as effective as calcium dobesilate 500 mg BID for the treatment of patients with chronic venous insufficiency.展开更多
Calcium salt is an important contributing factor for calcium-based biomineralization.To study the effect of calcium salt on soil biomineralization using crude soybean urease,the calcium salts,including the calcium chl...Calcium salt is an important contributing factor for calcium-based biomineralization.To study the effect of calcium salt on soil biomineralization using crude soybean urease,the calcium salts,including the calcium chloride (CaCl_(2)),calcium acetate ((CH_(3)COO)_(2)Ca) and calcium nitrate (Ca(NO_(3))_(2)),were used to prepare the biotreatment solution to carry out the biomineralization tests in this paper.Two series of biomineralization tests in solution and sand column,respectively,were conducted.Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed to determine the microscopic characteristics of the precipitated calcium carbonate (CaCO_(3)) crystals.The experimental results indicate that the biomineralization effect is the best for the CaCl2 case,followed by (CH_(3)COO)_(2)Ca,and worst for Ca(NO_(3))_(2) under the test conditions of this study (i.e.1 mol/L of calcium salt-urea).The mechanism for the effect of the calcium salt on the biomineralization of crude soybean urease mainly involves: (1) inhibition of urease activity,and (2) influence on the crystal size and morphology of CaCO_(3).Besides Ca^(2+) ,the anions in solution can inhibit the activity of crude soybean urease,and NO_(3)− has a stronger inhibitory effect on the urease activity compared with both CH_(3)COO^(−) and Cl^(−) .The co-inhibition of Ca^(2+) and NO_(3)− on the activity of urease is the key reason for the worst biomineralization of the Ca(NO_(3))_(2) case in this study.The difference in biomineralization between the CaCl_(2) and (CH_(3)COO)_(2) Ca cases is strongly correlated with the crystal morphology of the precipitated CaCO_(3).展开更多
Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Cal...Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Calcium(Ca),as a signaling molecule,is involved in the regulation of plant root development.However,the detailed underlying regulatory mechanism is elusive.In this study,we analyzed the morphological and transcriptomic variations of 84K poplar(Populus alba×P.glandulosa)in response to different calcium concentrations and found that low Ca^(2+)(1 mmol·L^(-1))promoted lateral root development,while deficiency(0.1 mmol·L^(-1)Ca^(2+))inhibited lateral root development.Co-expression analysis showed that Ca^(2+)channel glutamate receptors(GLRs)were present in various modules with significance for root development.Two GLR paralogous genes,PagGLR3.3a and Pag GLR3.3b,were mainly expressed in roots and up-regulated under Ca^(2+)deficiency.The CRISPR/Cas9-mediated signal gene(crispr-PagGLR3.3a,PagGLR3.3b)and double gene(crispr-PagGLR3.3ab)mutants presented more and longer lateral roots.Anatomical analysis showed that crispr-PagGLR3.3ab plants had more xylem cells and promoted the development of secondary vascular tissues.Further transcriptomic analysis suggested that knockout of PagGLR3.3a and PagGLR3.3b led to the up-regulation of several genes related to protein phosphorylation,auxin efflux,lignin and hemicellulose biosynthesis as well as transcriptional regulation,which might contribute to lateral root growth.This study not only provides novel insight into how the Ca^(2+)channels mediated root growth and development in trees,but also provides a directive breeding of new poplar species for biofuel and bioenergy production.展开更多
Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development rema...Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development remain largely unclear.Here,we identified the gene GhMCU4 encoding a MCU protein that negatively regulates plant development and fiber elongation in cotton(Gossypium hirsutum).GhMCU4expressed constitutively in various tissues with the higher transcripts in elongating fiber cells.Knockdown of GhMCU4 in cotton significantly elevated the plant height and root length.The calcium signaling pathway was significantly activated and calcium sensor genes,including Ca^(2+)dependent modulator of interactor of constitutively active ROP(GhCMI1),calmodulin like protein(GhCML46),calciumdependent protein kinases(GhCPKs),calcineurin B-like protein(GhCBLs),and CBL-interacting protein kinases(GhCIPKs),were dramatically upregulated in GhMCU4-silenced plants.Metabolic processes were preferentially enriched,and genes related to regulation of transcription were upregulated in GhMCU4-silenced plants.The contents of Ca^(2+)and H_(2)O_(2)were significantly increased in roots and leaves of GhMCU4-silenced plants.Fiber length and Ca^(2+)and H_(2)O_(2)contents in fibers were significantly increased in GhMCU4-silenced plants.This study indicated that GhMCU4 plays a negative role in regulating cell elongation in cotton,thus expanding understanding in the role of MCU proteins in plant growth and development.展开更多
Neuron-astrocyte interactions are vital for the brain’s connectome.Understanding astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in ...Neuron-astrocyte interactions are vital for the brain’s connectome.Understanding astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in different cortical states and associated behaviors in mammals.Studies on animal sleep and wakefulness have revealed distinct cortical synchrony patterns between neurons.Astrocytes,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic function.Recent research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium waves as key components of ion channel signaling.This summary focuses on a few recent studies investigating astrocyte-neuron interactions in mouse models during sleep,wakefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical states.These findings highlight the significant impact of astrocytes on large-scale neuronal networks,influencing brain activity and responsiveness.Targeting astrocytic signaling pathways shows promise for treating sleep disorders and arousal dysregulation.More research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the way for therapeutic interventions in sleep-and arousal-related disorders.展开更多
基金the National Natural Science Foundation of China(21978128,91934302)the State Key Laboratory of Materials-oriented Chemical Engineering(ZK202006)is acknowledged.
文摘Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from coal.Here,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium looping.For comparison,a coal-to-acetylene process was also established by using coal as feedstock.The carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically analyzed.Moreover,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) furnace.Even though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA process.With sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA process.This work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier.
基金financial support of the National Natural Science Foundation of China(U21A20218 and 32101857)the‘Double First-Class’Key Scientific Research Project of Education Department in Gansu Province,China(GSSYLXM-02)+1 种基金the Fuxi Young Talents Fund of Gansu Agricultural University,China(Gaufx03Y10)the“Innovation Star”Program of Graduate Students in 2023 of Gansu Province,China(2023CXZX681)。
文摘The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas.
基金supported by fund from the National Natural Science Foundation of China(32172322)。
文摘Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability or dysfunction may be the key stimulating factors to activate NLRP3 inflammasome,and sustained Ca^(2+)transfer can result in mitochondrial dysfunction.We focused on KCs to explore the damage to mitochondria by EA.After EA stimulation,cells produced an oxidative stress(OS)response with a significant increase in ROS release.Immunoprecipitation experiments and the addition of inhibitors revealed that the increase in the level of intracellular Ca^(2+)led to Ca^(2+)accumulation in the mitochondrial matrix via mitochondria-associated membranes(MAMs).This was accompanied by a significant release of m ROS,loss of MMP and ATP,and a significant increase in mitochondrial permeability transition pore opening,ultimately leading to mitochondrial instability.These findings confirmed the mechanism that EA induced mitochondrial Ca^(2+)imbalance in KCs via MAM,ultimately leading to mitochondrial dysfunction.Meanwhile,EA induced OS and the decrease of MMP and ATP in rat liver,and significant lesions were found in liver mitochondria.Swelling of the inner mitochondrial cristae and mitochondrial vacuolization occurred,with a marked increase in lipid droplets.
基金supported by the National Science Foundation of China (32171941,31571583)。
文摘Plant calmodulins(CaMs)and calmodulin-like proteins(CMLs)mediate Ca~(2+)signaling in response to abiotic stresses.Manipulation of this signaling in crops could increase stress tolerance.We review methods for detecting Ca~(2+)signals,regulatory roles of Ca Ms and CMLs,binding targets,and Ca~(2+)networks under abiotic stress in organelles.
基金supported by the National Natural Science Foundation of China (32072191)Daxing District Major Scientific and Technological Achievements Transformation Project (2020006)+1 种基金Beijing Innovation Team Project of Livestock Industry Technology SystemBeijing Science and Technology Special Project (Z201100002620005)。
文摘The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorating postmenopausal osteoporosis in a rat model established using bilateral ovariectomy.After 3 months of FM(containing vitamin D,and casein phosphopeptides,1000 mg Ca/100 g)or control milk(110 mg Ca/100 g milk)supplementation,bone changes were assessed using dual-energy X-ray absorptiometry,microcomputed tomography,and bone biomechanical testing.The results revealed that FM can regulate bone metabolism and gut microbiota composition,which act on bone metabolism through pathways associated with steroid hormone biosynthesis,relaxin signaling,serotonergic synapse,and unsaturated fatty acid biosynthesis.Furthermore,FM administration significantly increased bone mineral content and density in the lumbar spine and femur,as well as femoral compressive strength,while improving femoral trabecular bone parameters and microarchitecture.Mechanistically,we found that the effects may be due to increased levels of estrogen,bone formation marker osteocalcin,and procollagen typeⅠN-propeptide,and decreased expression of the bone resorption marker C-telopiptide and tartrate-resistant acid phosphatase 5b.Overall,the findings suggest that FM is a potential alternative therapeutic option for ameliorating postmenopausal osteoporosis.
基金supported by the National Natural Science Foundation of China[No.51820105010 and 51888103]support from Jiangsu Province(No.BK20202008,BE2022024,BE2022602,BK20220001,BK20220009,and BK20220077).
文摘Solar thermochemical energy storage based on calcium looping(CaL)process is a promising technology for next-generation concentrated solar power(CSP)systems.However,conventional calcium carbonate(CaCO_(3))pellets suffer from slow reaction kinetics,poor stability,and low solar absorptance.Here,we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability,mechanical strength,and solar absorptance via Al–Mn–Fe oxides.The energy storage density of proposed CaCO_(3)pellets is still as high as 1455 kJ kg^(-1)with only a slight decay rate of 4.91%over 100 cycles,which is higher than that of state-of-the-art pellets in the literature,in stark contrast to 69.9%of pure CaCO_(3)pellets over 35 cycles.Compared with pure CaCO_(3),the energy storage power density or decomposition rate is improved by 120%due to lower activation energy and promotion of Ca^(2+)diffusion by binary sulfate.The energy release or carbonation rate rises by 10%because of high O^(2-)transport ability of molten binary sulfate.Benefiting from fast energy storage/release rate and high solar absorptance,thermochemical energy storage efficiency is enhanced by more than 50%under direct solar irradiation.This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate,high energy density,good cyclic stability,and high solar absorptance simultaneously.
文摘Introduction: COVID-19 vaccine uptake and acceptance have been a major global concern due to the prevalent misinformation and disinformation that has characterized the vaccine rollout worldwide. This study aimed to assess COVID-19 vaccine uptake and acceptance, and associated factors among selected community members in two states in southwestern Nigeria. Method: We conducted a cross-sectional study using a multistage sampling technique. Fifty catchment settlements of 10 health facilities in each of Oyo and Ogun States targeted for a COVID-19 infection prevention and control intervention were randomly selected. Four households were targeted per settlement. All households that refused access were replaced, to ensure a minimum of four households randomly selected per settlement. The primary household decision-maker was interviewed in each household. Information elicited included respondents’ sociodemographic characteristics, health history, knowledge, risk and benefit perception about the COVID-19 vaccine, vaccine uptake, and willingness to be vaccinated. The study was conducted from July–August 2021. Data were analyzed using SPSS IBM version 23. Result: Four hundred household decision-makers were surveyed in Oyo and Ogun states, after replacement. The mean age of the respondents was 43.0 ± 11.0 years. The majority, 346 (86.5%) had heard about COVID-19 vaccination, but only 47 (13.6%) had received a COVID-19 vaccination. Of the 299 respondents who reported not receiving a COVID-19 vaccination, 166 (55.5%) were willing to be vaccinated. In univariate analysis, respondents who were female had tertiary education, perceived that COVID-19 vaccines are free and accessible, perceived that COVID-19 vaccines have minimal side effects, and perceived higher benefits of COVID-19 vaccination had higher odds of being vaccinated. In contrast, younger respondents, respondents with higher knowledge scores on COVID-19 preventive measures, and with chronic illness had lower likelihoods of being vaccinated. In multivariate analysis, only the respondent’s age, perception score on COVID-19 vaccine benefits, knowledge score on IPC measures, and positive response on accessibility and safety were significant after adjusting for other factors. Conclusion: COVID-19 vaccine uptake rate as well as willingness to receive vaccination were low in the study setting. There is an urgent need for policymakers to embark on well-designed campaigns to address barriers to COVID-19 vaccination to increase vaccine uptake.
文摘Oil-water separation for produced water (PW) originating from an oil extraction site in South Kuwait was carried out using bleached, esterified cellulosic material from used coffee grounds. Thereafter, earth-alkaline metal ions, specifically calcium ions, of the de-oiled PW were removed by precipitation with sodium carbonate to give access to pure sodium chloride as industrial salt from the remaining PW. While the purity of the precipitated calcium carbonate (CaCO3) depends on the precipitation conditions, CaCO3 of up to 95.48% purity can be obtained, which makes it a salable product. The precipitation of CaCO3 decreases the amount of calcium ions in PW from 11,300 ppm to 84 ppm.
基金Funded by the National Natural Science Foundation of China(No.52172287)the National Key Research and Development Program of China(No.2021YFA0715700)。
文摘Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic strength.However,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP nanospheres.Furthermore,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like crystals.These results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.
基金supported by the National Key Research Center and Development Program of the 14th Five-Year Plan,China(No.2022YFC2905105)National Natural Science Foundation of China(Nos.52122406 and 52004337)+2 种基金Hunan High-tech Industry Technology Innovation Leading Plan,China(No.2022GK4056)Hunan Innovative Province Construction Special Project,China(No.2020RC3001)Hunan Postgraduate Research and Innovation Project,China(No.CX20220200).
文摘Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed in this work.This innovative process raised the fluor-ite’s grade to 97.26wt%while producing nanoscale calcium carbonate from its leachate,which contained plenty of calcium ions.On the production of nanoscale calcium carbonate,the impacts of concentration,temperature,and titration rate were examined.By modifying the process conditions and utilizing crystal conditioning agents,calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511μm were produced.The influence of the impurity ions Mn^(2+),Mg^(2+),and Fe^(3+)was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride solution.The combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources,thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles.
基金supported by the Deutsche Forschungsgemeinschaft (ME1922/14-1) to AM。
文摘The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interaction partners, and the physiological and pathophysiological role of the NECAB family.
基金Project supported financially by the Program for the Development of Science and Technology of Jilin Province,China(Grant Nos.YDZJ202301ZYTS382,YDZJ202201ZYTS316,and 20230101285JC)the National Natural Science Foundation of China(Grant No.11904128)+1 种基金the Program for Science and Technology of Education Department of Jilin Province,China(Grant Nos.JJKH20220438KJ and JJKH20220423KJ)the Program for the Jilin Provincial Development and Reform Commission Project(Grant No.2022C040-6)。
文摘The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressibility of Ca(N_(3))_(2)changed as the pressure increased,and no phase transition occurred within the pressure from ambient pressure up to 54 GPa.The measured zero-pressure bulk modulus of Ca(N_(3))_(2)is higher than that of other alkali metal azides,due to differences in the ionic character of their metal-azide bonds.Using CASTEP,all vibration modes of Ca(N_(3))_(2)were accurately identified in the vibrational spectrum at ambient pressure.In the high-pressure vibration study,several external modes(ext.)and internal bending modes(ν_(2))of azide anions(N_(3)^(-))softened up to~7 GPa and then hardened beyond that pressure.This evidence is consistent with the variation observed in the F_(E)–f_(E)data analyzed from the XRD result,where the slope of the curve changes at 7.1 GPa.The main behaviors under pressure are the alternating compression,rotation,and bending of N_(3)^(-)ions.The bending behavior makes the structure of Ca(N_(3))_(2)more stable under pressure.
文摘Introduction: Pregnant women are a highly vulnerable population for COVID-19 with increased risk of hospitalization, intensive-care unit admission, invasive ventilation support, and mortality. Objective: This study determined the socio-demographic and economic factors associated with the uptake of COVID-19 vaccine among pregnant women utilizing antenatal care services in Pumwani Maternity Hospital, Nairobi County-Kenya. Methods: The study was carried out from 15 June to 23 July 2023. Systematic sampling was used to select 302 women from whom data was collected through face-to-face interviews using a pre-tested semi-structured questionnaire. Data was analyzed using SPSS software in which bivariate and multivariate logistic regression analyses were done at a significance level of p Results: A total of 302 pregnant women participated in the study. Of these, 105 (34.8%) were aged between twenty-six (26) and thirty (30) years. The mean age of the women was 28.60 ± (SD = 5.297). The uptake of the COVID-19 vaccine was 41.1%. The common side effects reported to be associated with the vaccines were fever, headache, joint pain, vomiting and skin rash. Uptake of the COVID-19 vaccine was significantly associated with being married (AOR = 3.65, 95% CI: 0.62 - 1.80, p = 0.001), having a secondary level of education (AOR = 3.78, 95% CI: 0.99 - 2.88, p = 0.001) and being employed (COR = 2.66, 95% CI: 1.31 - 3.06, p = 0.001). Conclusion: COVID-19 vaccination uptake remains low among pregnant women in seeking ANC in Nairobi. The individual factors associated with the uptake of COVID-19 vaccine among pregnant Women at Pumwani maternity hospital in Nairobi County were being married, having secondary level of education and being employed. Integration of the COVID-19 vaccine with other routine vaccinations as per the national immunization program in Kenya and the enhancement of education regarding the safety and efficacy of the COVID-19 vaccine in pregnancy and breastfeeding and economic empowerment of women are recommended.
基金supported by the National Natural Science Foundation of China(No.82370838 and No.82172221).
文摘Extracellular vesicles(EVs)are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity,natural functionality,and excellent biocompatibility.However,limitations such as low uptake efficiency,insufficient production,and inhomogeneous performance undermine their potential.To address these issues,numerous researchers have put forward various methods and applications for enhancing EV uptake in recent decades.In this review,we introduce various methods for the cellular uptake of EVs and summarize recent advances on the methods and mechanisms for enhancing EV uptake.In addition,we provide further understanding regarding enhancing EV uptake and put forward prospects and challenges for the development of EV-based therapy in the future.
基金Funded by the National Natural Science Foundation of China (Nos.51772033, 52002040)the National Key Research and Development Program of China (No. 2023YFB3711400)。
文摘The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementitious material. The composite system of calcium carbonate and aluminate minerals is studied by measuring the component of hydration products, the hydration heat, setting time and compressive strength.The results prove that the composite system has certain cementitious properties and is feasible to prepare new low-carbon cement.
文摘Background: Chronic venous insufficiency (CVI) describes a condition that affects the venous system of the lower extremities due to venous hypertension (VH. The prevalence is between 5% - 30%. CVI is associated with older age, smoking, lower extremity trauma, presence of an arteriovenous shunt, and elevated estrogen levels. All patients should be initially treated with conservative management. Venoactive drugs like calcium dobesilate are useful. Objectives: The primary objective compared the clinical improvement in patients with CVI, grades 0 - 3 of the CEAP classification of chronic venous disease, produced by two formulations of calcium dobesilate: calcium dobesilate LP 1 g OD vs calcium dobesilate 500 mg BID, immediate release. The secondary objective assessed the side effects of both formulations. Method: All patients took one tablet and one capsule at 7 am, and one capsule at 7 pm, for 8 weeks. One group received dobesilate 1 g OD and the other group received dobesilate 500 md BID. They were evaluated after 15, 30 and 60 days of treatment, using the symptom evaluation scale. Results: In both groups, there was a significant decrease in the symptom score after 15 days. Four patients in the Dobesilate OD group: had adverse effects, which did not require suspension of treatment. In the BID dobesilate group, there was one therapeutic failure, and one case of gastric discomfort. Conclusions: Prolonged-release Calcium dobesilate 1 g OD is as effective as calcium dobesilate 500 mg BID for the treatment of patients with chronic venous insufficiency.
基金the financial support by the National Natural Science Foundation of China(NSFC)(Grant Nos.52178319 and 52108307)the Natural Science Foundation of Fujian Province,China(Grant No.2022J05127).
文摘Calcium salt is an important contributing factor for calcium-based biomineralization.To study the effect of calcium salt on soil biomineralization using crude soybean urease,the calcium salts,including the calcium chloride (CaCl_(2)),calcium acetate ((CH_(3)COO)_(2)Ca) and calcium nitrate (Ca(NO_(3))_(2)),were used to prepare the biotreatment solution to carry out the biomineralization tests in this paper.Two series of biomineralization tests in solution and sand column,respectively,were conducted.Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed to determine the microscopic characteristics of the precipitated calcium carbonate (CaCO_(3)) crystals.The experimental results indicate that the biomineralization effect is the best for the CaCl2 case,followed by (CH_(3)COO)_(2)Ca,and worst for Ca(NO_(3))_(2) under the test conditions of this study (i.e.1 mol/L of calcium salt-urea).The mechanism for the effect of the calcium salt on the biomineralization of crude soybean urease mainly involves: (1) inhibition of urease activity,and (2) influence on the crystal size and morphology of CaCO_(3).Besides Ca^(2+) ,the anions in solution can inhibit the activity of crude soybean urease,and NO_(3)− has a stronger inhibitory effect on the urease activity compared with both CH_(3)COO^(−) and Cl^(−) .The co-inhibition of Ca^(2+) and NO_(3)− on the activity of urease is the key reason for the worst biomineralization of the Ca(NO_(3))_(2) case in this study.The difference in biomineralization between the CaCl_(2) and (CH_(3)COO)_(2) Ca cases is strongly correlated with the crystal morphology of the precipitated CaCO_(3).
基金supported by the National Natural Science Foundation of China(Grant Nos.32371902,31901327)National Key Research and Development Program of China(Grant Nos.2019YFE0119100,2021YFD2200205)+1 种基金Overseas Expertise Introduction Project for Discipline Innovation(111 Project D18008)The researches foundation of Zhejiang A&F University(Grant No.2018FR013)。
文摘Poplar is one of the fastest-growing temperate trees in the world and is widely used in ornamental horticulture for shade.The root is essential for tree growth and development and its utilization potential is huge.Calcium(Ca),as a signaling molecule,is involved in the regulation of plant root development.However,the detailed underlying regulatory mechanism is elusive.In this study,we analyzed the morphological and transcriptomic variations of 84K poplar(Populus alba×P.glandulosa)in response to different calcium concentrations and found that low Ca^(2+)(1 mmol·L^(-1))promoted lateral root development,while deficiency(0.1 mmol·L^(-1)Ca^(2+))inhibited lateral root development.Co-expression analysis showed that Ca^(2+)channel glutamate receptors(GLRs)were present in various modules with significance for root development.Two GLR paralogous genes,PagGLR3.3a and Pag GLR3.3b,were mainly expressed in roots and up-regulated under Ca^(2+)deficiency.The CRISPR/Cas9-mediated signal gene(crispr-PagGLR3.3a,PagGLR3.3b)and double gene(crispr-PagGLR3.3ab)mutants presented more and longer lateral roots.Anatomical analysis showed that crispr-PagGLR3.3ab plants had more xylem cells and promoted the development of secondary vascular tissues.Further transcriptomic analysis suggested that knockout of PagGLR3.3a and PagGLR3.3b led to the up-regulation of several genes related to protein phosphorylation,auxin efflux,lignin and hemicellulose biosynthesis as well as transcriptional regulation,which might contribute to lateral root growth.This study not only provides novel insight into how the Ca^(2+)channels mediated root growth and development in trees,but also provides a directive breeding of new poplar species for biofuel and bioenergy production.
基金supported by National Key Research and Development Program of China(2022YFD1200300)Jiangsu Key R&D Program(BE2022384)the Collaborative Innovation Center for Modern Crop Production co-sponsored by Province and Ministry(CIC-MCP)(No.10)。
文摘Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic cells.How MCU proteins regulate Ca^(2+)flow and modulate plant cell development remain largely unclear.Here,we identified the gene GhMCU4 encoding a MCU protein that negatively regulates plant development and fiber elongation in cotton(Gossypium hirsutum).GhMCU4expressed constitutively in various tissues with the higher transcripts in elongating fiber cells.Knockdown of GhMCU4 in cotton significantly elevated the plant height and root length.The calcium signaling pathway was significantly activated and calcium sensor genes,including Ca^(2+)dependent modulator of interactor of constitutively active ROP(GhCMI1),calmodulin like protein(GhCML46),calciumdependent protein kinases(GhCPKs),calcineurin B-like protein(GhCBLs),and CBL-interacting protein kinases(GhCIPKs),were dramatically upregulated in GhMCU4-silenced plants.Metabolic processes were preferentially enriched,and genes related to regulation of transcription were upregulated in GhMCU4-silenced plants.The contents of Ca^(2+)and H_(2)O_(2)were significantly increased in roots and leaves of GhMCU4-silenced plants.Fiber length and Ca^(2+)and H_(2)O_(2)contents in fibers were significantly increased in GhMCU4-silenced plants.This study indicated that GhMCU4 plays a negative role in regulating cell elongation in cotton,thus expanding understanding in the role of MCU proteins in plant growth and development.
基金supported by the Corbett Estate Fund(62285-531021-41800,to EW)the Helen Vosburg McCrillus Plummer and Robert Edward Lee Plummer,Jr.Chair Fund(to JHH).
文摘Neuron-astrocyte interactions are vital for the brain’s connectome.Understanding astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in different cortical states and associated behaviors in mammals.Studies on animal sleep and wakefulness have revealed distinct cortical synchrony patterns between neurons.Astrocytes,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic function.Recent research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium waves as key components of ion channel signaling.This summary focuses on a few recent studies investigating astrocyte-neuron interactions in mouse models during sleep,wakefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical states.These findings highlight the significant impact of astrocytes on large-scale neuronal networks,influencing brain activity and responsiveness.Targeting astrocytic signaling pathways shows promise for treating sleep disorders and arousal dysregulation.More research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the way for therapeutic interventions in sleep-and arousal-related disorders.