热加工食品中晚期糖基化终末产物和5-羟甲基糠醛的形成、检测与控制

食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,同时可能诱发氧化应激、炎症和动脉粥样硬化。5-HMF的代谢物5-磺基氧甲基糠醛(5-sulfooxymethylfurfural,5-SMF)有潜在基因毒性和致癌性。如何控制热加工食品中这些危害物的形成已成为食品行业的关注焦点。本文从美拉德反应和焦糖化反应两条途径探究了AGEs和5-HMF的形成机理,并对近5年二者的检测方法进行了综述,阐述了各类方法的优缺点,以期为建立二者的通用检测方法奠定基础。在此基础上,从削减前体物质的供给、阻断中间体的转化,以及去除已经生成的AGEs和5-HMF这3个方面着手,综述了近年来相应所采用的抑制策略,以期为AGEs和5-HMF在食品中的控制及热加工食品质量与安全管理提供理论依据。

化橘红提取物在早期糖尿病肾病大鼠中多靶点防治作用的研究

目的探究化橘红提取物在糖尿病肾病(diabetic nephropathy,DN)中的多靶点防治作用。方法对大鼠腹腔注射STZ试剂制备DN模型。将90只Wistar实验大鼠分为为正常对照组、模型空白组、贝那普利对照组、化橘红提取物预防组、化橘红提取物低剂量组和化橘红提取物高剂量组。检测各组FBG、HbA1C、U-mA1b、β_(2)-MG、SCr、BUN水平,同时检测SGLT2、AGES、RAGES、TGF-β1的mRNA及蛋白表达水平。结果模型空白组FBG、HbA1C、U-mA1b、β_(2)-MG、BUN水平均较正常对照组升高,SGLT2、AGES、RAGES、TGF-β1的mRNA和蛋白表达水平均较正常对照组升高,中西药物干预后上述指标均较模型空白组降低(P<0.05);其中,中药预防组干预效果最佳。结论化橘红提取物的作用机制可能是通过调节葡萄糖转运蛋白的异常表达、减少糖基化作用而减少TGF-β1表达水平,发挥防治DN、保护肾脏损伤的作用。

空气煎炸温度和时间对香菇品质和晚期糖基化终末产物形成的影响

研究空气煎炸温度和时间对香菇(Lentinulaedodes)品质和晚期糖基化终末产物(advanced glycation end products, AGEs)形成的影响。以香菇为原料,通过不同温度(160、180℃)和时间(0、5、10、15、20min)的空气煎炸,测定香菇含水量、色泽、硬度,进行感官评定,并分析香菇中荧光性AGEs和非荧光性AEGs——羧甲基赖氨酸(Nε-(carboxymethyl)-lysine, CML)和羧乙基赖氨酸(Nε-(carboxyethyl)-lysine, CEL)3种美拉德反应产物的含量。结果表明:空气煎炸10、15、20 min时,180℃处理香菇的含水量显著低于160℃;其中180℃,空气煎炸20 min时,香菇含水量最低。与新鲜香菇相比,180℃空气煎炸20 min时亮度值L*最低,红度值a*、黄度值b*、色泽总差值ΔE和硬度最高。160、180℃时,与空气煎炸5 min相比,20 min时形态得分、色泽得分、香味得分、综合得分最低;180℃空气煎炸10 min的酥脆度最高。与新鲜香菇相比,180、160℃空气煎炸10 min时荧光性AGEs含量差异不显著,180℃时空气煎炸20 min时,荧光性AGEs含量最高;160℃空气煎炸20 min的CML含量最高;180℃空气煎炸20 min的CEL含量最高;160、180℃空气煎炸10 min时CML和CEL含量差异不显著。综上,180℃、10min为空气煎炸香菇的良好条件,此时香菇的色泽风味及口感均良好且荧光性AGEs、CEL及CML含量较低。

果蔬发酵黑化褐变机制及晚期糖基化产物调控研究进展

果蔬的发酵黑化是其自身物质在高温、高湿的环境中产生的物理化学变化。黑化后的果蔬其营养价值丰富,但同时黑化过程中可能产生的晚期糖基化产物也对人体存在潜在危害。该文介绍了果蔬黑化褐变作用机制,其主要发生美拉德反应,酶促褐变和微生物作用等;简述了晚期糖基化产物的产生与危害,可能会导致糖尿病人产生一系列糖尿病并发症,诱导骨细胞凋亡,促进人体衰老等;总结了抑制晚期糖基化产物积累的方法,比如通过调控食品的工艺条件或者添加天然活性产物来抑制晚期糖基化产物的产生。未来可通过优化黑化反应条件或抑制美拉德反应进程来抑制晚期糖基化产物等有害物质的生成,得到更健康安全的黑化产品,从而预防或减轻人体疾病。

基于热糖化法体外生化抗糖化评价体系的优化与应用

面对日益增长的抗糖化原料筛选需求,现有的体外生化抗糖化评价体系、抗糖化细胞模型和人体功效评价方法因周期长或成本高等问题,不适用于原料的大规模初筛。实验周期短、成本低、操作简便、重复性好用于抗糖化原料初步筛选的评价方法亟待确立。基于热糖化法对体外生化抗糖化评价体系进行了优化,通过检测阿魏酸、原花青素、芦丁、L-抗坏血酸等8种原料进行了抑制荧光性AGEs(Advanced glycation end products)、降解荧光性AGEs原料筛选适用性探究。并将筛选结果与已发表研究、检测AGEs降解能力的AGEs-胶原蛋白交联破坏能力实验结果进行对比,对体系筛选能力、优势和局限性进行了讨论分析。确立了优化后的反应体系为:20 mg/mL牛血清白蛋白、1 mol/L葡萄糖、0.1 mol/L PBS缓冲液组成的反应体系下,50℃、孵育48 h后,在λ_(ex)/λ_(em)=370/452 nm波长下进行荧光强度的检测。在抑制/降解荧光性AGEs的测试中,测试2%的阿魏酸、原花青素、芦丁溶液抑制率分别达到56%,86%,95%,具有较好的抗糖化效果,阿魏酸、芦丁表现出潜在降解AGEs的趋势。优化后的体系,虽然在降解荧光性AGEs的应用上,相较于AGEs-胶原蛋白交联破坏能力测试的方法,在对照体系设置及实验结果上存在一定的局限性。但在筛选抑制荧光性AGEs的原料方面,结果稳定性、真实性佳,极大缩短了试验周期,为抗糖化功效添加剂的筛选和相应产品的开发提供了快速、稳定、节约经济成本的技术平台。

The intrinsic developmental age signal defines an age-dependent climbing behavior in cucumber

The tendril is a climbing organ in cucurbits and functions in physical support and to avoid shading by neighboring vegetation.However,how cucurbits produce tendrils to obtain climbing ability is largely unknown.In this study,tendril phenotypes were investigated during different developmental stages.Our results revealed that tendril growth exhibited an age-dependent pattern in cucurbits.Tendril growth was inhibited,and the tendril was formed as a short tendril[nonfunctional tendril(nonF-tendril),approximately 0.1 cm]during the seedling stage.In contrast,enhanced cell proliferation and cell expansion led to rapid elongation of the tendril during the climbing stage,and the tendril formed as a functional tendril(F-tendril,approximately 30 cm)to obtain climbing ability.RT-qPCR detection showed that age-dependent tendril growth correlated negatively with the abundance of the conserved age regulator CsmiR156.Defoliation induced CsmiR156 to inhibit CsSPLs,and F-tendril formation and climbing ability were delayed in defoliated cucumbers,which confirmed the role of CsmiR156 in regulating tendril growth in vivo.Additionally,exogenous gibberellin(GA)treatment showed that GA positively regulated tendril growth,and RT-qPCR detection showed that the GA bio-synthetic genes and metabolic genes were affected by age pathway,suggesting that the age pathway depended on GA bio-synthetic and metabolic pathway to regulate cell expansion to determine tendril growth.In summary,our work reveals that change in tendril type is an important marker of phase transition in cucumber,and tendril growth is regulated by an intrinsic developmental age signal,ensuring that the cucumber obtains climbing ability at a suitable age.

Afforestation with an age-sequence of Mongolian pine plantation promotes soil microbial residue accumulation in the Horqin Sandy Land, China

Land use change affects the balance of organic carbon(C)reserves and the global C cycle.Microbial residues are essential constituents of stable soil organic C(SOC).However,it remains unclear how microbial residue changes over time following afforestation.In this study,16-,23-,52-,and 62-year-old Mongolian pine stands and 16-year-old cropland were studied in the Horqin Sandy Land,China.We analyzed changes in SOC,amino sugar content,and microbial parameters to assess how microbial communities influence soil C transformation and preservation.The results showed that SOC storage increased with stand age in the early stage of afforestation but remained unchanged at about 1.27-1.29 kg/m2 after 52 a.Moreover,there were consistent increases in amino sugars and microbial residues with increasing stand age.As stand age increased from 16 to 62 a,soil pH decreased from 6.84 to 5.71,and the concentration of total amino sugars increased from 178.53 to 509.99 mg/kg.A significant negative correlation between soil pH and the concentration of specific and total amino sugars was observed,indicating that the effects of soil acidification promote amino sugar stabilization during afforestation.In contrast to the Mongolian pine plantation of the same age,the cropland accumulated more SOC and microbial residues because of fertilizer application.Across Mongolian pine plantation with different ages,there was no significant change in calculated contribution of bacterial or fungal residues to SOC,suggesting that fungi were consistently the dominant contributors to SOC with increasing time.Our results indicate that afforestation in the Horqin Sandy Land promotes efficient microbial growth and residue accumulation in SOC stocks and has a consistent positive impact on SOC persistence.

Can serum immunoglobulin G4 levels and age serve as reliable predictors of relapse in autoimmune pancreatitis?

We are writing in response to the paper published in the World Journal of Gastroenterology by Zhou et al.The authors identified higher serum immunoglobulin(Ig)G4 levels and age over 55 years as independent risk factors for disease relapse.Despite notable strengths,it is crucial to address potential biases.Firstly,the cohort study included 189 patients with autoimmune pancreatitis(AIP)type 1(with higher IgG4 seropositivity and higher relapse)and 24 with type 2(with lower IgG4 seropositivity and lower relapse).Consequently,most,if not all,AIP type 2 patients were assigned to the normal group,possibly inflating the association of higher serum IgG4 levels with relapse and potentially exaggerating the association of older age with relapse.Secondly,the authors did not provide sufficient details regarding AIP diagnosis,such as the ratio of definitive vs probable cases and the proportion of biopsies.In cases where histological evidence is unavailable or indeterminate,AIP type 2 may be misdiagnosed as definitive type 1,and type 1 may also be misdiagnosed as probable type 2,particularly in cases with normal or mildly elevated serum IgG4 levels.Lastly,in this retrospective study,approximately one-third of the consecutive patients initially collected were excluded for various reasons.Accordingly,the impact of nonrandom exclusion on relapse outcomes should be carefully considered.In conclusion,the paper by Zhou et al offers plausible,though not entirely compelling,evidence suggesting a predictive role of elevated serum IgG4 levels and advanced age in AIP relapse.The foundation for future investigations lies in ensuring a reliable diagnosis and accurate disease subtyping,heavily dependent on obtaining histological specimens.In this regard,endoscopic ultrasound-guided fine-needle biopsy emerges as a pivotal component of the diagnostic process,contributing to mitigating biases in future explorations of the disease.

Aging Mongolian pine plantations face high risks of drought-induced growth decline:evidence from both individual tree and forest stand measurements

Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited areas.An important species for afforestation in dry environments of northern China,Mongolian pine(Pinus sylvestris var.mongolica Litv.)has recently exhibited growth decline and dieback on many sites,particularly pronounced in old-growth plantations.However,changes in response to drought stress by this species with age as well as the underlying mechanisms are poorly understood.In this study,tree-ring data and remotely sensed vegetation data were combined to investigate variations in growth at individual tree and stand scales for young(9-13 years)and aging(35-52 years)plantations of Mongolian pine in a water-limited area of northern China.A recent decline in tree-ring width in the older plantation also had lower values in satellited-derived normalized difference vegetation indices and normalized difference water indices relative to the younger plantations.In addition,all measured growth-related metrics were strongly correlated with the self-calibrating Palmer drought severity index during the growing season in the older plantation.Sensitivity of growth to drought of the older plantation might be attributed to more severe hydraulic limitations,as reflected by their lower sapwood-and leaf-specific hydraulic conductivities.Our study presents a comprehensive view on changes of growth with age by integrating multiple methods and provides an explanation from the perspective of plant hydraulics for growth decline with age.The results indicate that old-growth Mongolian pine plantations in water-limited environments may face increased growth declines under the context of climate warming and drying.

Aboveground carbon sequestration of Cunninghamia lanceolata forests:Magnitude and drivers

Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management options.How carbon density and sequestration in various Cunninghamia lanceolata forests,extensively cultivated for timber production in subtropical China,vary with biodiversity,forest structure,environment,and cultural factors remain poorly explored,presenting a critical knowledge gap for realizing carbon sequestration supply potential through management.Based on a large-scale database of 449 permanent forest inventory plots,we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in Cunninghamia lanceolate forests in Hunan Province,China,and attributed the contributions of stand structure,environmental,and management factors to the heterogeneity using quantile age-sequence analysis,partial least squares path modeling(PLS-PM),and hot-spot analysis.The results showed lower values of carbon density and sequestration on average,in comparison with other forests in the same climate zone(i.e.,subtropics),with pronounced spatial and temporal variability.Specifically,quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests(0.50 and 1.80 Mg·ha^(-1)·yr^(-1)).PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature forests.Furthermore,species diversity and geotopographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low-and high-carbon-bearing forests.Hotspot analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon sequestration.Our work highlighted that retaining largesized DBH trees and increasing shade-tolerant tree species were important to enhance carbon sequestration in C.lanceolate forests.

An Overview on the Composition and Age of Upper Crust of Proto-Tethyan Lajishan Intra-oceanic Arc,NE Tibet Plateau

Identification and anatomy of oceanic arcs within ancient orogenic belt are significant for better understanding the tectonic framework and closure process of paleo-ocean basin.This article summarizes the geological,geochemical,and geochronological characteristics of upper crust of Proto-Tethyan Lajishan intra-oceanic arc and provides new data to constrain the subduction evolution of the South Qilian Ocean.The intra-oceanic arc volcanic rocks,including intermediate-mafic lava,breccia,tuff,and minor felsic rocks,are distributed along southern part of the Lajishan ophiolite belt.Geochemical and isotopic compositions indicate that the intermediate-mafic lava were originated from depleted mantle contaminated by sediment melts or hydrous fluids,whereas the felsic rocks were likely generated by partial melting of juvenile mafic crust in intra-oceanic arc setting.Zircons from felsic rocks yield consistent and concordant ages ranging from 506 to 523 Ma,suggesting these volcanic rocks represent the relicts of upper crust of the Cambrian intra-oceanic arc.Combined with the Cambrian forearc ophiolite and accretionary complex,we suggest that the Cambrian intra-oceanic arc in the Lajishan ophiolite belt is belonging to the intra-oceanic arc system which was generated by south-directed subduction in the South Qilian Ocean at a relatively short interval between approximately 530 and 480 Ma.

Age of Information for Short-Packet Covert Communication with Time Modulated Retrodirective Array

In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is designed to maximize the antenna gain in the target direction while the side lobe is sufficiently suppressed.On this basis,the covertness constraint and CAoI are derived in closed form.To facilitate the covert transmission design,the transmit power and block-length are jointly optimized to minimize the CAoI,which demonstrates the trade-off between covertness and timelessness.Our results illustrate that there exists an optimal block-length that yields the minimum CAoI,and the presented optimization results can achieve enhanced performance compared with the fixed block-length case.Additionally,we observe that smaller beam pointing error at Bob leads to improvements in CAoI.

Serum ferritin and the risk of early-onset colorectal cancer

BACKGROUND The incidence of early-onset colorectal cancer(EO-CRC)is rising in the United States,and is often diagnosed at advanced stages.Low serum ferritin is often incidentally discovered in young adults,however,the indication for endoscopy in EO-CRC is unclear.AIM To compare serum ferritin between patients with EO-CRC and healthy controls(HCs),and examine the association of serum ferritin in EO-CRC with patient-and disease-specific characteristics.METHODS A retrospective study of patients<50 years with newly-diagnosed EO-CRC was conducted from 1/2013-12/2023.Patients were included if serum ferritin was measured within 2 years prior to 1 year following CRC histologic diagnosis.To supplement the analysis,a cohort of HCs meeting similar inclusion and exclusion criteria were identified for comparison.A sensitivity analysis including only patients with serum ferritin obtained at or before diagnosis was separately performed to minimize risk of confounding.RESULTS Among 85 patients identified with EO-CRC(48 females),the median serum ferritin level was 26 ng/mL(range<1-2759 ng/mL).Compared to HCs(n=80211),there were a higher proportion of individuals with EO-CRC with serum ferritin<20 ng/mL(female 65%,male 40%)versus HCs(female 32.1%,male 7.2%)age 29-39 years(P=0.002 and P<0.00001,respectively).Stage IV disease was associated with significantly higher serum ferritin compared to less advanced stages(P<0.001).Serum ferritin obtained before or at the time of diagnosis was lower than levels obtained after diagnosis.Similar findings were confirmed in the sensitivity analysis.CONCLUSION Severe iron deficiency may indicate an increased risk of EO-CRC,particularly at earlier stages.Further studies defining the optimal serum ferritin threshold and routine incorporation of serum ferritin in screening algorithms is essential to develop more effective screening strategies for EO-CRC.

Association of preschool children behavior and emotional problems with the parenting behavior of both parents

BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.AIM To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children.METHODS From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool Children.Children’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional performance.Parenting behavior was evaluated using the Parental Behavior Inventory.Binomial logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting behaviors.RESULTS High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior problems.High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children.High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P<0.05).Moreover,paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors(all P>0.05),after calculating ratio of odds ratio values.CONCLUSION Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children.Overall,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or controlling the parents are,the more behavioral and emotional problems the children face.Moreover,the impact of fathers’parenting behaviors on preschool children’s behavior and emotions is no less significant than that of mothers’parenting behaviors.

Characteristics of the HIV/AIDS Epidemic among People Aged≥50 Years in China during 2018–2021

Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to 2021.It also aimed to recommend targeted interventions for the prevention and treatment of HIV/AIDS in elderly patients.Methods Data on newly reported cases of PLWHA,aged≥50 years in China from 2018 to 2021,were collected using the CRIMS.Trend tests and spatial analyses were also conducted.Results Between 2018 and 2021,237,724 HIV/AIDS cases were reported among patients aged≥50 years in China.The main transmission route was heterosexual transmission(91.24%).Commercial heterosexual transmission(CHC)was the primary mode of transmission among males,while non-marital non-CHC([NMNCHC];60.59%)was the prevalent route in women.The proportion of patients with CHC decreased over time(Z=67.716,P<0.01),while that of patients with NMNCHC increased(Z=153.05,P<0.01).The sex ratio varied among the different modes of infection,and it peaked at 17.65 for CHC.The spatial analysis indicated spatial clustering,and the high-high clustering areas were mainly distributed in the southwestern and central-southern provinces.Conclusion In China,PLWHA,aged≥50 years,were predominantly infected through heterosexual transmission.The primary modes of infection were CHC and NMNCHC.There were variations in the sex ratio among different age groups,infected through various sexual behaviors.HIV/AIDS cases exhibited spatial clustering.Based on these results,the expansion of HIV testing,treatment,and integrated behavioral interventions in high-risk populations is recommended to enhance disease detection in key regions.

Laboratory Evaluation of Performance Recovery of Aged SBS-modified Asphalt Using Regenerants with Different Base Oil Components

In this study,the regenerative effects of different regenerants on aged SBS-modified asphalt from different perspectives were investigated,including their conventional properties,viscoelastic behavior,creep-related properties,and micromorphology.Base oils composed of different proportions of aromatic and saturated hydrocarbons as well as the styrene-butadiene-styrene(SBS)restorer were used to prepare the regenerants.The results showed that the components of the base oil of the regenerant played a crucial role in determining the characteristics and performance of the recycled SBSmodified asphalt.Regenerants containing a high proportion of aromatics dissolved the hard segment in the SBS restorer,thereby delaying the effect of a reduction in the regenerants on the performance of the aged asphalts at a high temperature.Regenerants containing a high proportion of saturates dissolved the soft segment in the SBS restorer to enhance the lowtemperature performance of the recycled asphalts.In addition,the stress sensitivity of the recycled asphalts increased with the fraction of aromatics in the regenerant.As the aromatic content of the base oil components of the regenerants increased and their saturate content decreased,the state of dispersion of the SBS phase in the recycled SBS-modified asphalts improved.The optimal content of aromatics in the base oil of the regenerants should be set in the range of 33%to 47%to ensure the adequate performance of the recycled asphalts and a high efficiency of the SBS restorer.

MSADCN:Multi-Scale Attentional Densely Connected Network for Automated Bone Age Assessment

Bone age assessment(BAA)helps doctors determine how a child’s bones grow and develop in clinical medicine.Traditional BAA methods rely on clinician expertise,leading to time-consuming predictions and inaccurate results.Most deep learning-based BAA methods feed the extracted critical points of images into the network by providing additional annotations.This operation is costly and subjective.To address these problems,we propose a multi-scale attentional densely connected network(MSADCN)in this paper.MSADCN constructs a multi-scale dense connectivity mechanism,which can avoid overfitting,obtain the local features effectively and prevent gradient vanishing even in limited training data.First,MSADCN designs multi-scale structures in the densely connected network to extract fine-grained features at different scales.Then,coordinate attention is embedded to focus on critical features and automatically locate the regions of interest(ROI)without additional annotation.In addition,to improve the model’s generalization,transfer learning is applied to train the proposed MSADCN on the public dataset IMDB-WIKI,and the obtained pre-trained weights are loaded onto the Radiological Society of North America(RSNA)dataset.Finally,label distribution learning(LDL)and expectation regression techniques are introduced into our model to exploit the correlation between hand bone images of different ages,which can obtain stable age estimates.Extensive experiments confirm that our model can converge more efficiently and obtain a mean absolute error(MAE)of 4.64 months,outperforming some state-of-the-art BAA methods.

Early Paleozoic basement diorite of arc-magmatism from Kutch basin, Western India

In this study,we report for thefirst time an Early Palaeozoic basement diorite from the drilled well Nirona-A in the Banni Half-Graben of the Kutch basin,western India.The 40Ar–39Ar dates provided a plateau age of 441.84±2.66 Ma and another pseudo plateau of 441.28±5.82 to 388.08±16.65 Ma for the basement diorite.These ages constrain the basement formation age to the Late Ordovician-Early Silurian period.The obtained basement ages are correlatable with the later part of Cambro-Ordovician alkaline magmatism that has been reported from the Huqf area in Central Oman,whereas their lithological and petrographic correlativity with base-ment diorites occurring in the Dinsi Body of Nagar Parkar igneous complex in Pakistan can also be envisaged.The geochemical studies characterized the diorite with enrich-ment of LILE(Rb,Ba,and K)and LREE(La,Ce,Nd),strong depletion of HFSE(Nb,Sr,P,and Ti),along with weakly negative Eu anomalies.The geochemical signatures indicate their petrogenetic affiliation with mantle-derived magmas,as well as their tectonic setting to be arc-related,having post-collisional continental-arc type affinity.The*440 Ma basement of Kutch,therefore,appears to rep-resent the later thermal event associated with the reworked Neoproterozoic subduction-related suite from Greater India’s northwest edge,which has implications for Gond-wana assembly in the northwest Indian subcontinent.

Ecological effect of the plantation of Sabina vulgaris in the Mu Us Sandy Land,China

Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid areas.This study aimed to explore the ecological effect of the plantation of Sabina vulgaris on soil physical and chemical properties on the southeastern fringe of the Mu Us Sandy Land,China.We collected soil samples from five depth layers(0-20,20-40,40-60,60-80,and 80-100 cm)in the S.vulgaris plantation plots across four plantation ages(4,7,10,and 16 years)in November 2019,and assessed soil physical(soil bulk density,soil porosity,and soil particle size)and chemical(soil organic carbon(SOC),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),available potassium(AK),cation-exchange capacity(CEC),salinity,p H,and C/N ratio)properties.The results indicated that the soil predominantly consisted of sand particles(94.27%-99.67%),with the remainder being silt and clay.As plantation age increased,silt and very fine sand contents progressively rose.After 16 years of planting,there was a marked reduction in the mean soil particle size.The initial soil fertility was low and declined from 4 to 10 years of planting before witnessing an improvement.Significant positive correlations were observed for the clay,silt,and very fine sand(mean diameter of 0.000-0.100 mm)with SOC,AK,and p H.In contrast,fine sand and medium sand(mean diameter of 0.100-0.500 mm)showed significant negative correlations with these indicators.Our findings ascertain that the plantation of S.vulgaris requires 10 years to effectively act as a windbreak and contribute to sand fixation,and needs 16 years to improve soil physical and chemical properties.Importantly,these improvements were found to be highly beneficial for vegetation restoration in arid and semi-arid areas.This research can offer valuable insights for the protection and restoration of the vegetation ecosystem in the sandy lands in China.

Effects of tree size and organ age on variations in carbon,nitrogen,and phosphorus stoichiometry in Pinus koraiensis

Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains limited.We determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast China.Soil factors were also measured.The results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil factors.At a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree size.At the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric ratios.Our results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual level.It is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for survival.Conversely,nutrient storage strategy in older trees and organ fractions are mainly for steady growth.Our results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations.