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The stability and passivity of delayed neural networks are addressed in this paper. A novel Lyapunov-Krasovskii functional (LKF) without multiple integrals is constructed. By using an improved matrix-valued polynomial inequality (MVPI), the previous constraint involving skew-symmetric matrices within the MVPI is removed. Then, the stability and passivity criteria for delayed neural networks that are less conservative than the existing ones are proposed. Finally, three examples are employed to demonstrate the meliority and feasibility of the obtained results., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Since the coronavirus disease 2019 (COVID-19) epidemic, insomnia has become one of the longer COVID-19 symptoms. This study aimed to investigate insomnia among COVID-19 survivors and explore the occurrence and influencing factors of insomnia. A cross-sectional study was performed from December 2022 to February 2023 through an online questionnaire star survey with 8 questions. The insomnia severity index scale (ISI) was used to assess the severity of insomnia. Univariate analysis was used to analyze the factors related to COVID-19 infection. A total of 564 participants (183 males and 381 females) were surveyed in the present study. The prevalence of insomnia was 63.12%. Among these insomnia patients, there were 202 (35.82%) with sub-threshold symptoms, 116 (20.57%) with moderate symptoms, and 38 (6.74%) with severe symptoms. Univariate analysis indicated that there were statistically significant differences in the prevalence of insomnia among COVID-19 survivors of different ages, occupations, and educational levels (P < .05). Of the 356 insomnia patients, 185 (51.97%) did not take any measures against insomnia, while those who took drugs only, physical exercise only, drugs and physical exercise, and other measures were 90 (25.28%), 42 (11.80%), 17 (4.78%), and 22 (6.18%), respectively. Additionally, of the 107 insomnia patients with drug therapy, 17 (15.89%) took estazolam, 16 (14.95%) took alprazolam, 39 (36.45%) took zopiclone, and 35 (32.71%) took other drugs to improve insomnia symptoms. The prevalence of insomnia symptoms remains high among COVID-19 survivors in China. Education level and occupation may be the influencing factors. Unfortunately, most patients with insomnia do not take corresponding treatment measures., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Hyperglycemia is the main feature of diabetes and may increase the risk of vascular calcification (VC), which is an independent predictor for cardiovascular and cerebrovascular diseases (CCD). Selenium (Se) may decrease the risk of CCD, and previous studies confirmed that Se-containing protein from Se-enriched Spirulina platensis (Se-SP) exhibited novel antioxidant potential. However, the effect of Se-SP against VC has been not investigated. Herein, the protective effect and underlying mechanism of Se-SP against high glucose-induced calcification in mouse aortic vascular smooth muscle cells (MOVAS) were explored. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) results showed time-dependent uptake of Se-SP in MOVAS cells, which significantly inhibited high glucose-induced abnormal proliferation. Se-SP co-treatment also effectively attenuated high glucose-induced calcification of MOVAS cells, followed by decreased activity and expression of alkaline phosphatase (ALP). Further investigation revealed that Se-SP markedly prevented reactive oxygen species (ROS)-mediated DNA damage in glucose-treated MOVAS cells. ROS inhibition by glutathione (GSH) effectively inhibited high glucose-induced calcification, indicating that Se-SP could act as ROS inhibitor to inhibit high glucose-induced DNA damage and calcification. Moreover, Se-SP dramatically attenuated high glucose-induced dysfunction of mitogen-activated protein kinases (MAPKs) and phosphatidylinositol-3-kinase/AKT (PI3K/AKT) pathways. Se-SP after Se addition achieved enhanced potential in inhibiting high glucose-induced calcification, which validated that Se-SP as a new Se species could be a highly effective treatment for human CCD., (Copyright © 2020 Lin, Zhang, Li, Zhang, Shen, Kong, Wang, Cui, Dai, Cao and Zhang.)

Thermal conductivity of soil is a basic physical property related to heat conduction, and also is one of parameters widely applied in geotechnical engineering. The effect of gradation on the thermal conductivity of fused quartz was analyzed by thermal needle tests. The different particle size with the same uniformity coefficient (C u  = 3.2) and different uniformity coefficient for the same particle size (0.10~1.00 mm) were considered in this study. It shows that the thermal conductivity of fused quartz decreases with the decreasing of the mean particle size and with the increasing of the porosity. Simple modified methods to estimate the value of thermal conductivity are proposed, and had been demonstrated successfully by conducting fused quartz, carbonate sand and Ottawa sand.

Objective: To investigate the levels of period circadian protein homolog 3 (PER3) in paclitaxel-resistant prostate cancer patients and the effect of PER3 on paclitaxel-resistant prostate cancer cell lines., Patients and Methods: A total of 38 patients diagnosed with prostate cancer in our hospital from June 2013 to June 2016 were divided into paclitaxel-resistant group (n=19) and non-resistant group (n=19) according to the follow-up treatment effects. Fluorescent quantitative polymerase chain reaction (PCR) was performed to evaluate the levels of PER3 in drug-resistant and non-resistant groups as well as the relative levels of PER3 before and after treatment. PER3 was overexpressed or knocked down in a paclitaxel-resistant prostate cancer cell line, followed by measuring its IC50 as well as changes in cell cycle and apoptosis. Using Western blot, we detected downregulation of Notch pathway and related receptor proteins when PER3 was overexpressed., Results: The results of fluorescence quantitative PCR showed that the expression of PER3 in the paclitaxel-resistant prostate cancer group was lower than that in the non-resistant group, and the relative expression of PER3 was decreased after treatment. Fluorescent quantitative PCR and Western blot showed that the expression of PER3 in paclitaxel-resistant prostate cancer cells was higher than that of the untreated counterparts. After overexpression of PER3 by transfecting prostate cancer-resistant cell lines with plasmids, the IC50 was significantly reduced, the cell cycle was arrested, and the apoptosis was significantly increased. Subsequently, we detected decreased expression of Notch1 in PER3 over-expressed paclitaxel-resistant cell lines by Western blot; this attenuated resistance in paclitaxel-resistant cell lines., Conclusions: PER3 can induce sensitivity of paclitaxel-resistant cell lines to paclitaxel by inhibiting the expression of Notch1.

Based on our initial genome-wide association study (GWAS) on esophageal squamous cell carcinoma (ESCC) in Han Chinese, we conducted a follow-up study to examine the single nucleotide polymorphisms (SNPs) associated with family history (FH) of upper gastrointestinal cancer (UGI) cancer in cases with ESCC. We evaluated the association between SNPs and FH of UGI cancer among ESCC cases in a stage-1 case-only analysis of the National Cancer Institute (NCI, 541 cases with FH and 1399 without FH) and Henan GWAS (493 cases with FH and 869 without FH) data (discovery phase). The top SNPs (or their surrogates) from discovery were advanced to a stage-2 evaluation in additional Henan subjects (2801 cases with FH and 3136 without FH, replication phase). A total of 19 SNPs were associated with FH of UGI cancer in ESCC cases with P < 10 -5 in the stage-1 meta-analysis of NCI and Henan GWAS data. In stage-2, the association for rs79747906 (located at 18p11.31, P = 5.79 × 10 -6 in discovery) was replicated (P = 0.006), with a pooled-OR of 1.59 (95%CI: 1.11-2.28). We identified potential genetic variants associated with FH of UGI cancer. Our findings may provide important insights into new low-penetrance susceptibility regions involved in the susceptibility of families with multiple UGI cancer cases.

Objective: : This study aimed to determine if gastric cardia adenocarcinoma (GCA) risk was associated with the lys (A or *2) allele at the rs671 (glu504lys) polymorphism within the aldehyde dehydrogenase 2 ( ALDH2 ) gene in a Chinese Han population. We also aimed to investigate ALDH2 genotypic distributions between subjects from high- and low-incidence areas for both GCA and esophageal squamous cell carcinoma (ESCC)., Methods: : We designed a case-control study including 2,686 patients with GCA and 3,675 control subjects from high- and low-incidence areas for both GCA and ESCC in China. TaqMan allele discrimination assay was used to genotype the rs671 polymorphism. χ 2 test and binary logistic regression analysis were used to estimate the odds ratios for the development of GCA, and multivariate ordinal logistic regression was used to analyze ALDH2 genotypic distributions among different groups., Results: : Compared with ALDH2 *1/*1 homozygotes, ALDH2 *1/*2 and ALDH2 *2/*2 carriers did not increase the risk for GCA in the Chinese Han population ( P >0.05). Interestingly, the ratio of homozygous or heterozygous ALDH2 *2 carriers in high-incidence areas for both GCA and ESCC was lower than that in low-incidence areas ( P <0.001)., Conclusions: : Genotypes of rs671 at ALDH2 may not increase GCA susceptibility in Chinese Han populations. In addition, the ALDH2 genotypic distribution differs between Chinese Han populations from high- and low-incidence areas for both GCA and ESCC. Our findings may shed light on the possible genetic mechanism for the dramatic geographic differences of GCA occurrence in China.

Acute respiratory distress syndrome (ARDS) is a complex syndrome disorder with high mortality rate. Camel milk (CM) contains antiinflammatory and antioxidant properties and protects against numerous diseases. This study aimed to demonstrate the function of CM in lipopolysaccharide (LPS)-induced ARDS in rats. Camel milk reduced the lung wet:dry weight ratio and significantly reduced LPS-induced increases in neutrophil infiltration, interstitial and intra-alveolar edema, thickness of the alveolar wall, and lung injury scores of lung tissues. It also had antiinflammatory and antioxidant effects on LPS-induced ARDS. After LPS stimulation, the levels of proinflammatory cytokines (tumor necrosis factor-α, IL-10, and IL-1β) in serum and oxidative stress markers (malondialdehyde, myeloperoxidase, and total antioxidant capacity) in lung tissue were notably attenuated by CM. Camel milk also downregulated mitogen-activated protein kinase signaling pathways. Given these results, CM is a potential complementary food for ARDS treatment., (Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

In order to further standardize the diagnosis and treatment of schistosomiasis japonica in China, on the basis of evidence-based medicine, the experts on schistosomiasis control from Hunan, Hubei and Jiangxi provinces summarized their consensuses on the disease after the discussion on the current situation and progress of clinical diagnosis and treatment of schistosomiasis in China, with the reference to the Diagnostic Criteria for Schistosomiasis (WS261-2006), which aimed to establish the therapeutic standards or guideline of schistosomiasis in China.

Cyanidin-3-O-glucoside (C3G), an anthocyanin belonging to the flavonoid family and commonly present in food and vegetables in human diet, has exhibited anti-inflammatory and anti-oxidant effects. This study aimed to investigate the protective ability of C3G against inflammatory and oxidative injuries, as well as to clarify the possible mechanism in lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells (HUVECs) in vitro and acute respiratory distress syndrome mouse model in vivo. HUVECs or male Kunming mice were pretreated with C3G 1 h before LPS stimulation. C3G significantly inhibited the production of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin (IL) -6, and IL-1β) in cell supernatants and bronchoalveolar lavage fluid (BALF) as determined by enzyme-linked immunosorbent assay. Histopathologic examination with hematoxylin and eosinstaining showed that C3G pretreatment substantially suppressed inflammatory cell infiltration, alveolar wall thickening, and interstitial edemain lung tissues. C3G markedly prevented LPS-induced elevation of malondialdehyde and myeloperoxidase levels in lung tissue homogenates, wet to dry ratio of lung tissues, total cells, and inflammatory cells (neutrophils and macrophages) in BALF. Moreover, C3G reduced superoxide dismutase activity in the lung tissue homogenates. Western blot assay also showed that C3G pretreatment significantly suppressed LPS-induced activation of nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways by blocking the phosphorylation of inhibitor κB-α, NF-κB/P65, extracellular signal-regulated kinase, p38, and c-Jun NH2-terminal kinase in the lung tissues. In summary, C3G may ameliorate LPS-induced injury, which results from inflammation and oxidation, by inhibiting NF-κB and MAPK pathways and playing important anti-inflammatory and anti-oxidative roles.

Zwitterions and polyoxometalates (POMs) are two kinds of functional moieties with very different properties for applications in different fields. We have developed an effective strategy to successfully immobilize these two different moieties into the frameworks of porous hybrid materials, in which the POM units act as templates and photoactive moieties. These hybrid materials demonstrate remarkable efficiency for selective scavenging and photolysis of cationic dyes from polluted water, and up to 10% dye uptake and quantitative photolysis of dyes have been realized.

In traditional therapy with Chinese medicine, vitexin has several pharmacological properties, including antinociceptive, antispasmodic, antioxidant, antimyeloperoxidase, and α-glucosidase inhibitory activities. Recently, vitexin was shown to protect the heart against ischemia/reperfusion injury in an in vitro model by inhibiting apoptosis. The purpose of this study was to find out whether vitexin influences the effect on rat cytochrome P450 (CYP) enzymes (CYP1A2, CYP2C11, and CYP3A1) by using cocktail probe drugs in vivo; the influence on the levels of CYP mRNA was also studied. A cocktail solution at a dose of 5 mL/kg, which contained phenacetin (10 mg/kg), tolbutamide (1 mg/kg), and midazolam (5 mg/kg), was given as oral administration to rats treated with short or long period of intravenous vitexin via the caudal vein. Blood samples were collected at a series of time points, and the concentrations of probe drugs in plasma were determined by HPLC-mass spectrometry (MS)/MS. The corresponding pharmacokinetic parameters were calculated by the software of DAS 2.0. In addition, real-time reverse transcription-polymerase chain reaction was performed to determine the effects of vitexin on the mRNA expression of CYP1A2, CYP2C11, and CYP3A1 in rat liver. Treatment with short or long period of vitexin had no effects on rat CYP1A2. However, CYP3A1 enzyme activity was inhibited by vitexin in a concentration-dependent and time-dependent manner. Furthermore, CYP2C11 enzyme activity was induced after short period treatment but inhibited after long period of vitexin treatment. The mRNA expression results were in accordance with the pharmacokinetic results. In conclusion, vitexin can either inhibit or induce activities of CYP2C11 and CYP3A1. Therefore, caution is needed when vitexin is co-administered with some CYP2C11 or CYP3A1 substrates in clinic, which may result in treatment failure and herb-drug interactions., (Copyright © 2014 John Wiley & Sons, Ltd.)

Two new organic building units that contain dicarboxylate sites for their self-assembly with paddlewheel [Cu2(CO2)4] units have been successfully developed to construct two isoreticular porous metal-organic frameworks (MOFs), ZJU-35 and ZJU-36, which have the same tbo topologies (Reticular Chemistry Structure Resource (RCSR) symbol) as HKUST-1. Because the organic linkers in ZJU-35 and ZJU-36 are systematically enlarged, the pores in these two new porous MOFs vary from 10.8 Å in HKUST-1 to 14.4 Å in ZJU-35 and 16.5 Å in ZJU-36, thus leading to their higher porosities with Brunauer-Emmett-Teller (BET) surface areas of 2899 and 4014 m(2) g(-1) for ZJU-35 and ZJU-36, respectively. High-pressure gas-sorption isotherms indicate that both ZJU-35 and ZJU-36 can take up large amounts of CH4 and CO2, and are among the few porous MOFs with the highest volumetric storage of CH4 under 60 bar and CO2 under 30 bar at room temperature. Their potential for high-pressure swing adsorption (PSA) hydrogen purification was also preliminarily examined and compared with several reported MOFs, thus indicating the potential of ZJU-35 and ZJU-36 for this important application. Studies show that most of the highly porous MOFs that can volumetrically take up the greatest amount of CH4 under 60 bar and CO2 under 30 bar at room temperature are those self-assembled from organic tetra- and hexacarboxylates that contain m-benzenedicarboxylate units with the [Cu2(CO2)4] units, because this series of MOFs can have balanced porosities, suitable pores, and framework densities to optimize their volumetric gas storage. The realization of the two new organic building units for their construction of highly porous MOFs through their self-assembly with [Cu2(CO2)4] units has provided great promise for the exploration of a large number of new tetra- and hexacarboxylate organic linkers based on these new organic building units in which different aromatic backbones can be readily incorporated into the frameworks to tune their porosities, pore structures, and framework densities, thus targeting some even better performing MOFs for very high gas storage and efficient gas separation under high pressure and at room temperature in the near future., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Four porous metalloporphyrinic framework materials, [(CH3)2NH2][Zn2(HCOO)2(Mn(III)-TCPP)]·5DMF·2H2O (1; H6TCPP = tetrakis(4-carboxyphenyl)porphyrin), [(CH3)2NH2][Cd2(HCOO)2(Mn(III)-TCPP)]·5DMF·3H2O (2), [Zn2(HCOO)(Fe(III)(H2O)-TCPP)]·3DMF·H2O (3), and [Cd3(H2O)6(μ2-O)(Fe(III)-HTCPP)2]·5DMF (4) were synthesized by heating a mixture of M(III)Cl-H4TCPP (M = Mn and Fe) and M' (M' = Zn or Cd) nitrate in a mixed solvent of DMF and acetic acid. Compounds 1-3 are built up from M'2(COO)4 paddle-wheel subunits bridged by M(III)-TCPP and formate ligands to form their 3D connections. The formate pillar heterogeneously connects with M and M' cations in 1 and 2 and homogeneously joins M' cations in 3. The μ2-O bridged Fe(III)-HTCPP dimer performs as a decadentate ligand to link 10 cadmium cations for the formation of an interesting 3D coordination network of 4. The four porphyrinic frameworks present interesting catalytic properties in the selective epoxidation of olefins, oxidation of cyclohexane, and intermolecular aldol reaction of aldehydes and ketones.

Objective: To evaluate the therapeutic effect of endoscopic ligation in the treatment of advanced schistosomiasis patients with esophageal variceal bleeding., Methods: A total of 130 advanced schistosomiasis patients with esophageal varices rupture and bleeding were divided into a ligation group (68 cases) and a control group (64 cases), and the patients of ligation group were treated with the emergency endoscopic ligation, and the patients of control group received the routine therapy. The rebleeding rate, hemostatic success rate, and varicose veins red color sign were observed., Results: In the ligation group, the rebleeding rate was 10.3% and the positive rate of varicose veins red color sign was 8.8%, which were better than those in the control group (both P values <0.01)., Conclusion: Endoscopic ligation is an effective therapy for esophageal variceal bleeding.

Erectile dysfunction (ED) is a major complication of diabetes mellitus. Icariin has been shown to enhance erectile function through its bioactive form, icarisid II. This study investigates the effects of icarisid II on diabetic rats with ED and its potential mechanism via the assessment of advanced glycosylation end products (AGEs), autophagy, mTOR and the NO-cGMP pathway. Icarisid II was extracted from icariin by an enzymatic method. In the control and diabetic ED groups, rats were administered normal saline; in the icarisid II group, rats were administered icarisid II intragastrically. Erectile function was evaluated by measuring intracavernosal pressure/mean arterial pressure (ICP/MAP). AGE concentrations, nitric oxide synthase (NOS) activity and cGMP concentration were assessed by enzyme immunoassay. Cell proliferation was analysed using methyl thiazolyl tetrazolium assay and flow cytometry. Autophagosomes were observed by transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 localisation. The expression of NOS isoforms and key proteins in autophagy were examined by western blot. Our results have shown that Icarisid II increased ICP/MAP values, the smooth muscle cell (SMC) growth curve, S phase and SMC/collagen fibril (SMC/CF) proportions and decreased Beclin 1 (P<0.05). Icarisid II significantly increased the proliferative index and p-p70S6K(Thr389) levels and decreased the numbers of autophagosomes and the levels of LC3-II (P<0.01). Icarisid II decreased AGE concentrations and increased cGMP concentration, NOS activity (P<0.05) and cNOS levels (P<0.01) in the diabetic ED group. Therefore, Icarisid II constitutes a promising compound for diabetic ED and might be involved in the upregulation of SMC proliferation and the NO-cGMP pathway and the downregulation of AGEs, autophagy and the mTOR pathway.

A metal-organic nanotube (MONT) was synthesized by linking up the bent organic ligands and the tetra-coordinated zinc cations under mild conditions. Structural analysis revealed that the MONT has a very large exterior wall diameter of 4.91 nm and an interior channel diameter of 3.32 nm. Interlocking of the nanotubes gives rise to a 3D chiral framework containing 1D helical cylindered channels with diameter of 2.0 nm. The MONT has very interesting property by synergizing the functionality of nanotubes, metal-organic frameworks (MOFs), and N-heterocyclic carbenes (NHCs). The dye adsorption experiments demonstrate that the channels of the MONTs are accessible to large reagents typically used for catalysis. The postmodification of the MONT can be easily operated by unmarking the imidazolium moieties in the channel walls, which was conducted as a highly active heterogeneous catalyst for Suzuki-Miyaura and Heck coupling reactions, hydrogenation of olefins and nitrobenzene, while the constituent elements are less efficient for these reactions under the same conditions.

This study evaluated the relationship between altered cytoplasmic expression of TGF-β1 in tissues of the vaginal incisional margin and vaginal cancer recurrence in patients with stage Ib-IIa cervical squamous cell carcinoma (CSCC). This paper also discusses the prognostic value of TGF-β1 expression at these locations. We found that TGF-β1 expression in the vaginal margin had a close association with vaginal recurrence of stage Ib-IIa CSCC and was an independent prognostic marker of this disease.

Objective: To recommend a new clinical classification of advanced schistosomiasis for improving the diagnosis and evaluation of therapeutic effect of advanced schistosomiasis., Methods: The medical records of 11 092 cases of advanced schistosomiasis from the Xiang-Yue Hospital from January 1990 to January 2010 and the medical aid centre for advance schistosomiasis in Hunan Province from January 2004 to January 2010 were collected and classified with the current and new clinical classification methods and the results were statistically analyzed and compared., Results: Based on the current classification method, there were huge splenomegaly (5 710 cases), ascites (2 993 cases), colon proliferative (834 cases), and dwarf (54 cases). However, 1 501 cases were excluded from the current classification. Based on the new classification method, there were 8 types: huge splenomegaly (2 870 cases), ascites (1 885 cases), colon proliferative (425 cases), dwarf (38 cases), universal (1 281 cases), bleeding (1 857 cases), hepatic coma (553 cases), and miscellaneous (1 759 cases). Totally 424 cases were classified into chronic schistosomiasis., Conclusion: The new classification method can present a more comprehensive picture for clinical features, severe complications and prognosis of advanced schistosomiasis, and is useful for the diagnosis and treatment of advanced schistosomiasis.

A new bifunctional N-heterocyclic carbene (NHC) precursor was used to construct two metal-organic frameworks, which can anchor palladium(II) sites by post-modification, presenting remarkable framework dependent catalytic activities.

We performed a genome-wide association study of esophageal squamous cell carcinoma (ESCC) by genotyping 1,077 individuals with ESCC and 1,733 control subjects of Chinese Han descent. We selected 18 promising SNPs for replication in an additional 7,673 cases of ESCC and 11,013 control subjects of Chinese Han descent and 303 cases of ESCC and 537 control subjects of Chinese Uygur-Kazakh descent. We identified two previously unknown susceptibility loci for ESCC: PLCE1 at 10q23 (P(Han combined for ESCC) = 7.46 x 10(-56), odds ratio (OR) = 1.43; P(Uygur-Kazakh for ESCC) = 5.70 x 10(-4), OR = 1.53) and C20orf54 at 20p13 (P(Han combined for ESCC) = 1.21 x 10(-11), OR = 0.86; P(Uygur-Kazakh for ESCC) = 7.88 x 10(-3), OR = 0.66). We also confirmed association in 2,766 cases of gastric cardia adenocarcinoma cases and the same 11,013 control subjects (PLCE1, P(Han for GCA) = 1.74 x 10(-39), OR = 1.55 and C20orf54, P(Han for GCA) = 3.02 x 10(-3), OR = 0.91). PLCE1 and C20orf54 have important biological implications for both ESCC and GCA. PLCE1 might regulate cell growth, differentiation, apoptosis and angiogenesis. C20orf54 is responsible for transporting riboflavin, and deficiency of riboflavin has been documented as a risk factor for ESCC and GCA.

Based on the analysis of the distribution characteristics of delta13C values in the needle, twig, branch, trunk, and root of different age Abies georgei growing at the timberline of Sergyemla Mountain on the southeast edge of Tibetan Plateau, this paper studied the process or extent of post-photosynthetic delta13C fractionation and its affecting factors. The results showed that the organ-specific difference in delta13C values was highly significant (P < 0.001), with the sequence of trunk (-24.19 per thousand +/- 0.34 per thousand) > branch (-24.56 per thousand +/- 0.62 per thousand) > root (-25.05 per thousand +/- 1.08 per thousand) > twig (-25.12 per thousand +/- 0.54 per thousand) > needle (-7.25 per thousand +/- 0.63 per thousand), which suggested that an obvious post-photosynthetic delta13C fractionation was existed between photosynthetic and non-photosynthetic organs. With increasing age of needle and twig, the delta13C value in needle decreased significantly, while that in twig showed a reverse pattern (P < 0.01). The delta13C value in needle increased significantly (P < 0.01) from lower canopy to higher canopy, whereas no significant difference (P > 0.05) of delta13C value in twig was observed among different canopy heights. A significant vertical gradient of delta13C value existed in the branches at a distance of 2.5 m from trunk (P < 0.01), but disappeared at a distance of 1.5 m or 0.5 m. At the same canopy height, the delta13C value in twig decreased with increasing distance from trunk, which was most obvious in the twigs of middle and lower canopies. All of these suggested that post-photosynthetic delta13C fractionation occurred in alpine A. georgei, and the carbon need for the growth of height-specific tree stems or branches was not wholly supplied by the corresponding segment of the tree crown at the same height.