The impact of Persian oak (Quercus brantii Lindl.) on soil characteristics in a declining forest

Root activity has an important impact on soil development but we have little knowledge of the interaction of the root zone and soil genetic horizons.The aim of this investigation was to study the interactions between soil chemical characteristics and root zone processes in a declining Persian oak forest(Quercus brantii Lindl.).A randomized complete block design was used to investigate the long-term eff ect of Persian oak on soil horizons,and the chemical and biological properties in two soil zones(under and outside the canopy).Results indicate that the rhizosphere zone had signifi cantly higher total organic carbon(TOC)than outside the canopy soil in the upper soil horizons.In subsurface horizons,water-extractable organic carbon values were signifi cantly higher in rhizosphere than in non-rhizospheric zone.Microbial biomass carbon(MBC)values in the rhizospheric zone decreased from the fi rst to the second horizon.The MBC/TOC ratio indicated signifi-cant diff erences between the rhizosphere and soils outside of the canopy,with the exception of the subsurface horizon.In the subsurface horizon of the rhizosphere,there was greater respiration of organic carbon(ΣCO 2/TOC)than in outside of canopy soil.In addition,root processes infl uenced pH,nitrogen fractions,and availability of phosphorus,potassium,iron,zinc and manganese.Diff erences in soil characteristics between rhizospheric and non-rhizospheric zones were signifi cant in surface horizons due to higher root density than in deeper soil layers.The fi ndings indicate that Persian oak(Quercus brantii Lindl.)roots infl uenced the main soil chemical properties,even in calcareous soils.

Overflow Controlled Declining Rate Filtration: A Conceptual Design for Increased Flexibility and Dynamism

A declining rate filter operating through over flow control mode is proposed in this paper with a view to improving the overall performance of declining rate filters. Traditional declining rate filters have in-built self-adjustment of flow rates among the filters assisted with downstream orifice for flow control with limited flexibility for further adjustment. The proposed design allows the control of flow level and flow rates in individual filters, the water level in the over flow distributor tank and offers increased flexibility in responding to changes in filtration variables and optimising the overall performance of the filters. The design set up can also operate as constant rate filter through setting the water level in the distributor tank to the maximum.

An Inventory Model for Deteriorating Items with Exponential Declining Demand and Time-Varying Holding Cost

In the present paper, a total optimal cost of an inventory model with exponential declining demand and constant deterioration is considered. The time-varying holding cost is a linear function of time. Shortages are not allowed. The items (like food grains, fashion apparels and electronic equipments) have fixed shelf-life which decreases with time during the end of the season. A numerical example is presented to demonstrate the model and the sensitivity analysis of various parameters is carried out.

Welfare for the Aged in Nigeria,a Sustenance for the Declining Older Population and Aged Male in Nigeria

A buttress on the need for welfare program in Nigeria and the important obligation to consider the Economics’and CIA’s contextual position for the dependency ratios,both total and elderly dependency ratio alongside the consideration of the age structure and demography statistics of Nigeria relatively to other economies,particularly as an elixir for the declining older population in Nigeria and the aged male contraction in the nation.Although,older female population is higher in every country as obtainable globally,the Nigerian case is that of drastic contraction in both aged male and older population generally.Therefore,the submission is that the government has to consider the total dependency ratio to the elderly dependency ratio,which is all-encompassing in order to cater for the declining older population and to appropriate the requisite welfare cum benefits programs in the nation.

Japanese Enterprises Wish to Expand Investments in China,Despite Declining in 2015

Japan’s investment in China in2015 was$3.2 billion,which was a drop of 25.9%compared with the year before;as for trade,however,Japan was the second destination country for China’s exports,with a volume of$135.7 billion;as for imports,Japan ranked third with a volume of$143 billion.Japanese companies

Declining Rate of Operative Vaginal Deliveries in Nigeria

Background: The application of invasive obstetric procedures has an end point of reducing the Caesarean section rate. The declining rate of use of these procedures is one of the reasons for increasing Caesarean section rates in our environment. Objective: The aim of the study was to determine the practice of operative vaginal deliveries among obstetricians practicing in Nigeria and to evaluate the reasons for non-use of these procedures. Methodology: It was a questionnaire based study. The questionnaires were administered to practitioners of Obstetrics in the various centres in Nigeria. Data was collated and analyzed with Epi-Info statistical software version 7.0 (Center for Disease Control and Prevention, USA), and conclusions were drawn by means of descriptive statistics. Results: A total of 1200 questionnaire were distributed but 1104 were returned and used for analysis. This gave a response rate of 92%. The age distribution of the respondents showed that the 20 - 30 year age group had the least number of respondents 22 (2%) while 41 - 50 age group had the highest number of respondents 486 (4%). The majority of the respondents were males 839 (76%). In terms of duration of practice, 449 (40.7%) of the respondents had more than 6 years duration of practice while 256 (23.2) had practiced for less than 3 years. Tertiary centres had highest number of respondents 71.8%. The distribution of the respondents according to the geopolitical zones in Nigeria are;South-East (57.6%), South-South (19.6%), South West (11.4%), North-West (4.9%), North-East (3.8%), North-Central (2.7%). The practice of these procedures among respondents were: External cephalic version (68.0%), Symphysiotomy (41.7), Forceps delivery (68.8%), Destructive delivery (60.1%), Vaginal breech delivery (85.5%), Vacuum extraction (84.8%). Reasons for the non-use included: Risk of perinatal/maternal morbidity and mortality greater than benefit (25.7%), Lack of equipment (22.4%), Lack of skills (16.6%), Decline by patients (6.5%), Not in the departmental protocol (26.2%), Not evidence based (34.6%), Patient preferred Caesarean section (5.6%), Outdated (32.6%), fear of litigation (32.7%). The mean rate of caesarean section according to rates reported from different centres was 25.2% while the individual centre rates ranged from 2% to as high as 51%. Conclusion: There is a decline in the practice of operative obstetric procedures among obstetricians practicing in Nigeria. There is an urgent need to reverse this trend by increased training and re-training of manpower, provision of necessary equipment, more research to provide supportive evidence of need and inclusion in protocols.

Neuroprotective effects of G9a inhibition through modulation of peroxisome-proliferator activator receptor gamma-dependent pathways by miR-128

Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s disease.Therefore,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and neuroinflammation.To better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor UNC0642.We found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)mRNA.Accordingly,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control group.We also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a inhibitor.To confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative insult.In this setting,treatment with G9a inhibitor increases both cell survival and antioxidant enzymes.Moreover,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and apoptosis.In addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers expression.Finally,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a inhibition.Altogether,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.

Declining responsiveness of childhood Plasmodium falciparum infections to artemisinin-based combination treatments ten years following deployment as first-line antimalarials in Nigeria

Background:The development and spread of artemisinin-resistant Plasmodium falciparum malaria in Greater Mekong Subregion has created impetus for continuing global monitoring of efficacy of artemisinin-based combination therapies(ACTs). This post analyses is aimed to evaluate changes in early treatment response markers 10 years after the adoption of ACTs as first-line treatments of uncomplicated falciparum malaria in Nigeria.Methods: At 14 sentinel sites in six geographical areas of Nigeria, we evaluated treatment responses in 1341 children under 5 years and in additional 360 children under 16 years with uncomplicated malaria enrolled in randomized trials of artemether-lumefantrine versus artesunate-amodiaquine at 5-year interval in 2009-2010 and 2014-2015 and at 2-year interval in 2009-2010 and 2012-2015, respectively after deployment in 2005.Results: Asexual parasite positivity 1 day after treatment initiation (APPD1) rose from 54 to 62% and 2 days after treatment initiation from 5 to 26% in 2009-2010 to 2014-2015(P=0.002 and P<0.0001, respectively).Parasite clearance time increased significantly from 1.6 days (95% confidence interval [CI]: 1.55-1.64) to 1.9 days (95% C,1.9-2.0) and geometric mean parasite reduction ratio 2 days after treatment initiation decreased significantly from 11 000 to 4700 within the same time period (P< 00001 for each). Enrolment parasitaemia > 75 000 μl^-1, haematocrit > 27% 1 day post-treatment initiatiortreatment with artemether-lumefantrine and enrolment in 2014-2015 independently predicted APPD1. In paralle , Kaplan-Meier estimated risk of recurrent infections by day 28 rose from 8 to 14% (P=0005) and from 9 to 15%(P=0.02) with artemether-lumefantrine and artesunate-amodiaquine, respectively. Mean asexual parasitaemia half-life increased significantly from 1.1 h to 1.3h within 2 years (P<0.0001).Conclusions:These data indicate declining parasitological responses through time to the two ACTs may be due to emergence of parasites with reduced susceptibility or decrease in immunity to the infections in these children.

Study on Renewal Planning of Declining Historic Quarters:Inspired from the Discussion on Conservation of the Old City in South Nanjing

Through collecting,reflecting and summarizing various opinions on the conservation of the old city in South Nanjing,this paper examines the problems that the declining historic quarters are facing amid the urban renewal process.Moreover,in combination with the existing planning practices in the old city in South Nanjing,this paper carries out a discussion on the renewal of the declining historic quarters from the perspective of values,exploration and assessment of historic resources,choice of renewal methods,and support of implementation system.

Coupling between the Cenozoic west Pacific subduction initiation and decreases of atmospheric carbon dioxides

At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from~51 to 34 Ma.The cause of this phenomenon is still not well understood.In this study,we demonstrate that the initiation of Cenozoic west Pacific plate subduction,triggered by the hard collision in the Tibetan Plateau,occurred at approximately 51 Ma,coinciding with the tipping point.The water depths of the Pacific subduction zones are mostly below the carbonate compensation depths,while those of the Neo-Tethys were much shallower before the collision and caused far more carbonate subducting.Additionally,more volcanic ashes erupted from the west Pacific subduction zones,which consume CO_(2).The average annual west Pacific volvano eruption is 1.11 km~3,which is higher than previous estimations.The amount of annual CO_(2)absorbed by chemical weathering of additional west Pacific volcanic ashes could be comparable to the silicate weathering by the global river.We propose that the initiation of the western Pacific subduction controlled the long-term reduction of atmospheric CO_(2)concentration.

Efficacy of prednisone combined with mycophenolate mofetil for immunoglobulin A nephropathy with moderate-to-severe renal dysfunction

BACKGROUND Immunoglobulin A nephropathy(IgAN)is a common form of chronic glomer-ulonephritis.Currently,IgAN is one of the main causes of chronic renal failure in China;its prognosis varies greatly between patients,with renal function at the time of diagnosis and prognosis being strongly correlated.Mycophenolate mofetil(MMF)is a drug with a good immunomodulatory effect and is commonly used clinically.However,its effects in IgAN have not yet been clearly demonstrated.Therefore,herein,we retrospectively compared the effectiveness and safety of prednisone alone or combined with MMF for the treatment of primary IgAN with moderate-to-severe renal impairment.METHODS Between January 2011 and December 2020,200 patients with moderate-to-severe IgAN were included in this study,all of whom were admitted to Wuxi People's Hospital affiliated with Nanjing Medical University.All patients underwent a renal puncture biopsy,which revealed primary IgAN with a glomerular filtration rate(GFR)of 30–60 mL/min.The patients were divided into a glucocorticoid therapy group(GTG)and an immunosuppressive therapy group(ITG)according to the different treatment regimens,with 100 patients in each group.Based on general treatments,such as angiotensin-converting enzyme inhibitors/angiotensin receptor blockers,patients in the GTG were administered prednisone 0.5–0.8 mg/(kg·d^(-1))for 4–8 wk,which was reduced by 5 mg every two weeks until the maintenance(30 mg/d)dose was reached and maintained for 12 mo.In the ITG,MMF was administered at 1.0 g/d for 6–12 mo,followed by a maintenance dosage of 0.5 g/d for 12 mo.Age,sex,blood pressure,24-h urinary egg white measurement,serum creatinine(Scr),blood uric acid,blood albumin,blood potassium(K),hemoglobin,GFR,alanine aminotransferase,total cholesterol(T-CHO),fasting blood glucose,and body mass index were recorded.The 24-h urinary protein,Scr,and GFR levels were recorded 3,6,9,and 12 mo after treatment.Follow-up data were also collected.RESULTS No discernible differences existed between the two groups in terms of age,sex,blood pressure,creatinine,24-h urinary protein level,GFR,or other biochemical indicators at the time of enrollment.Both regimens significantly reduced the 24-h urinary protein quantitation and stabilized renal function.Nine months after treatment,the 24-h urinary protein and Scr of the ITG decreased more significantly than those of the GTG.By the 12th month of treatment,the 24-h urinary protein and Scr in both groups continued to decrease compared to those by the 9th month.In addition,the overall response rate in the ITG was significantly higher than that in the GTG.The occurrence of side effects did not vary significantly between the two regimens;however,endpoint events were significantly more common in the GTG than in the ITG.The follow-up time for the GTG was noticeably lower than that for the ITG.CONCLUSION Prednisone combined with MMF was effective for the treatment of IgAN with moderate-to-severe renal dysfunction.

Shale oil enrichment evaluation and production law in Gulong Sag,Songliao Basin,NE China

Based on the results of drilling,tests and simulation experiments,the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evolution,shale oil occurrence,and pore/fracture evolution mechanism.In conjunction with a substantial amount of oil testing and production data,the Gulong shale oil enrichment layers are evaluated and the production behaviors and decline law are analyzed.The results are drawn in four aspects.First,the Gulong shales are in the stage of extensive hydrocarbon expulsion when R_(0) is 1.0%-1.2%,with the peak hydrocarbon expulsion efficiency of 49.5%approximately.In the low-medium maturity stage,shale oil migrates from kerogen to rocks and organic pores/fractures.In the medium-high maturity stage,shale oil transforms from adsorbed state to free state.Second,the clay mineral intergranular pores/fractures,dissolution pores,and organic pores make up the majority of the pore structure.During the transformation,clay minerals undergo significant intergranular pore/fracture development between the minerals such as illite and illite/smectite mixed layer.A network of pores/fractures is formed by organic matter cracking.Third,free hydrocarbon content,effective porosity,total porosity,and brittle mineral content are the core indicators for the evaluation of shale oil enrichment layers.Class-I layers are defined as free hydrocarbon content equal or greater than 6.0 mg/g,effective porosity equal or greater than 3.5%,total porosity equal or greater than 8.0%,and brittle mineral content equal or greater than 50%.It is believed that the favourable oil layers are Q2-Q3 and Q8-Q9.Fourth,the horizontal wells in the core area of the light oil zone exhibit a high cumulative production in the first year,and present a hyperbolic production decline pattern,with the decline index of 0.85-0.95,the first-year decline rate of 14.5%-26.5%,and the single-well estimated ultimate recovery(EUR)greater than 2.0×10^(4)t.In practical exploration and production,more efforts will be devoted to the clarification of hydrocarbon generation and expulsion mechanisms,accurate testing of porosity and hydrocarbon content/phase of shale under formation conditions,precise delineation of the boundary of enrichment area,relationship between mechanical properties and stimulated reservoir volume,and enhanced oil recovery,in order to improve the EUR and achieve a large-scale,efficient development of shale oil.

Does pollinator dependence decrease along elevational gradients?

Plants have long been thought to be less dependent on pollinators for seed production at higher elevations due to adverse pollination environments.However,recent research has yet to consistently support the generality of this expectation.In this study,we asked whether pollinator dependence decreases along an elevational gradient and how it varies with various reproductive traits.To answer these questions,we quantified pollinator-plant associations and various reproductive traits for 112 flowering plants spanning a large elevational gradient(990-4260 m a.s.l.)in the Qinghai-Tibet Plateau.We found that flowering plants in the Qinghai-Tibet Plateau region are highly dependent on pollinators for seed production(76.2%of seed production was contributed by animal pollinators and 44.6%of plants would produce no seed without pollinator visitation).Contrary to our expectation,there was no significant elevational gradient in pollinator dependence index.Although the pollinator dependence index was not significantly correlated with pollen limitation,flower size,floral longevity,or reward type,it was correlated with compatibility status and flowering time.These findings indicate that pollinator dependence does not decrease along an elevational gradient in the Qinghai-Tibet Plateau.Our study also highlights the severe vulnerability of flowering plant seed production to pollinator declines under global change in the Qinghai-Tibet Plateau region,particularly for early-flowering or self-incompatible plants growing at higher elevations(e.g.,subnival belt).

Association Between Constipation and a Reduction in Lower Limb Muscle Strength in Preoperative Patients with Thoracic Spinal Tumors

Objective To investigate the clinical symptoms experienced by patients with thoracic spinal tumors and verify the associated symptoms that are predictive of a decline in muscle strength in the lower limbs.Methods A single-center,retrospective cross-sectional study was conducted on in-patients diagnosed with epidural thoracic spinal tumors between January 2011 and May 2021.The study involved a review of electronic medical records and radiographs and the collection of clinical data.The differences in clinical manifestations between patients with constipation and those without constipation were analyzed.Binary logistic regression analyses were performed to identify risk factors associated with a decline in muscle strength in the lower limbs.Results A total of 227 patients were enrolled,including 131 patients with constipation and 96 without constipation.The constipation group had a significantly higher proportion of patients who experienced difficulty walking or paralysis compared to those without constipation prior to surgery(83.2%vs.17.7%,χ~2=99.035,P 0.001).Constipation(OR=9.522,95%CI:4.150±21.849,P 0.001)and urinary retention(OR=14.490,95%CI:4.543±46.213,P 0.001)were independent risk factors for muscle strength decline in the lower limbs.Conclusions The study observed that patients with thoracic spinal tumors who experienced constipation symptoms had a higher incidence of lower limb weakness.Moreover,the analysis revealed that constipation and urinary retention were independent risk factors associated with a preoperative decline in muscle strength of lower limbs.

Alzheimer’s disease risk after COVID-19:a view from the perspective of the infectious hypothesis of neurodegeneration

In light of the rising evidence of the association between viral and bacterial infections and neurodegeneration,we aimed at revisiting the infectious hypothesis of Alzheimer’s disease and analyzing the possible implications of COVID-19 neurological sequelae in long-term neurodegeneration.We wondered how SARS-CoV-2 could be related to the amyloid-βcascade and how it could lead to the pathological hallmarks of the disease.We also predict a paradigm change in clinical medicine,which now has a great opportunity to conduct prospective surveillance of cognitive sequelae and progression to dementia in people who suffered severe infections together with other risk factors for Alzheimer’s disease.

Nutrient retranslocation strategies associated with dieback of Pinus species in a semiarid sandy region of Northeast China

In the semiarid sandy region of Northeast China,Mongolian pine(Pinus sylvestris var.mongolica)suffers dieback after the age of 35,while Japanese red pine(Pinus densiflora)and Chinese pine(Pinus tabuliformis)stay healthy.Foliar nutrient retranslocation reflects the nutrient conservation and utilization mechanism of plants in response to their habitats.However,the nutrient retranslocation strategies employed by three Pinus tree species to cope with nutrient limitations remain largely unknown.For this study,we investigated the seasonal variations in nitrogen(N)and phosphorus(P)concentrations of Mongolian pine,Japanese red pine,and Chinese pine plantations in terms of the green needles of all ages,senesced needles,and soil.Further,the N retranslocation efficiency(NRE),and P retranslocation efficiency(PRE),and correlations between the N:P ratios of needles and soil were analyzed.The results showed that,except for the spring NRE in 1-year-old needles of Mongolian pine,the spring NRE and PRE in 1-and 2-year-old needles of the three tree species were greater than zero.The autumn PRE was higher than zero for Mongolian pine,but lower than zero for Japanese red pine and Chinese pine.Among the three Pinus species,Mongolian pine showed greater spring PRE in 2-year-old needles,and PRE from 1-to 2-yearold needles,and from 2-year-old needles to litter.However,Japanese red pine had higher P concentrations and lower N:P ratios in senesced needles,while greater PRE was found in Chinese pine litter.Significant relationships between the N:P ratios were found in the current year and 1-year-old needles and soil in the Mongolian pine plantation,while there was an insignificant relationship between the N:P ratios of the needles and soil in the Chinese pine plantation.Thus,for Mongolian pine,the removal of P from needles in autumn,and higher P translocation from older needles under P-deficient soil may have contributed to the tree dieback.In contrast,Japanese red pine and Chinese pine stored P in their needles during autumn.Japanese red pine returned more P to the soil via litter,while Chinese pine maintained N:P homeostasis and increased P withdrawal prior to needle abscission.

Analysis of Key Physiological Characteristics of Portunus trituberculatus in Response to Short-Term Low Salinity Stress

Salinity is a significant environmental factor that can affect the survival,metamorphosis,growth and feeding of Portunus trituberculatus.In order to analyze the key physiological characteristics of P.trituberculatus in response to short-term low salinity stress,the experiments of gradually decline and recovery as well as abrupt decline in salinity were carried out.The results showed that P.trituberculatus could survive in a certain low salinity range in the short term,and salinity 12 was the lowest tolerable salinity under the present experimental conditions.The change of the hemolymph osmotic pressure displayed significant positive correlations with water salinity,and the pressure was always higher than seawater osmotic pressure.Short-term low salinity stress changed the structure and morphology of gill tissue.The expansion of gill filament ends and epithelial cell shedding were conducive to osmotic adjustment.The activities of key ion transport enzymes such as Na^(+)-K^(+)-ATPase,carbonic anhydrase and V-ATPase also changed with the osmotic regulation,while Na^(+)-K^(+)-ATPase played a dominant role.In summary,as an osmotic adjustment species,P.trituberculatus rapidly adapt to the short-term low-salinity environment by osmotic adjustment in vivo,but salinity below salinity 12 is not conducive to its survival.Our result enriched the theoretical mechanism of osmotic regulation of P.trituberculatus,providing reference for the development of aquaculture technology of P.trituberculatus.

Gut microbiota links with cognitive impairment in amyotrophic lateral sclerosis: A multi-omics study

Recently, cognitive impairments(CI) and behavioral abnormalities in patients with amyotrophic lateral sclerosis(ALS) have been reported. However, the underlying mechanisms have been poorly understood. In the current study, we explored the role of gut microbiota in CI of ALS patients. We collected fecal samples from 35ALS patients and 35 healthy controls. The cognitive function of the ALS patients was evaluated using the Edinburgh Cognitive and Behavioral ALS Screen. We analyzed these samples by using 16S rRNA gene sequencing as well as both untargeted and targeted(bile acids) metabolite mapping between patients with CI and patients with normal cognition(CN). We found altered gut microbial communities and a lower ratio of Firmicutes/Bacteroidetes in the CI group, compared with the CN group. In addition, the untargeted metabolite mapping revealed that 26 and 17 metabolites significantly increased and decreased, respectively, in the CI group, compared with the CN group. These metabolites were mapped to the metabolic pathways associated with bile acids. We further found that cholic acid and chenodeoxycholic acid were significantly lower in the CI group than in the CN group. In conclusion, we found that the gut microbiota and its metabolome profile differed between ALS patients with and without CI and that the altered bile acid profile in fecal samples was significantly associated with CI in ALS patients. These results need to be replicated in larger studies in the future.

Association between Serum Uric Acid and the Early Marker of Kidney Function Decline among Chinese Middle-Aged and Older Population:Evidence from the China Health and Retirement Longitudinal Study

Objective To evaluate the association between serum uric acid(SUA)and kidney function decline.Methods Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older population for analysis.The kidney function decline was defined as an annual estimated glomerular filtration rate(e GFR)decrease by>3 mL/min per 1.73 m^(2).Multivariable logistic regression was applied to determine the association between SUA and kidney function decline.The shape of the association was investigated by restricted cubic splines.Results A total of 7,346 participants were included,of which 1,004 individuals(13.67%)developed kidney function decline during the follow-up of 4 years.A significant dose-response relation was recorded between SUA and the kidney function decline(OR 1.14,95%CI 1.03-1.27),as the risk of kidney function decline increased by 14%per 1 mg/d L increase in SUA.In the subgroup analyses,such a relation was only recorded among women(OR 1.22,95%CI 1.03-1.45),those aged<60 years(OR 1.22,95%CI 1.05-1.42),and those without hypertension and without diabetes(OR 1.22,95%CI 1.06-1.41).Although the dose-response relation was not observed in men,the high level of SUA was related to kidney function decline(OR 1.83,95%CI 1.05-3.17).The restricted cubic spline analysis indicated that SUA>5 mg/dL was associated with a significantly higher risk of kidney function decline.Conclusion The SUA level was associated with kidney function decline.An elevation of SUA should therefore be addressed to prevent possible kidney impairment and dysfunction.