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Adamson P, An FP, Anghel I, Aurisano A, Balantekin AB, Band HR, Barr G, Bishai M, Blake A, Blyth S, Cao GF, Cao J, Cao SV, Carroll TJ, Castromonte CM, Chang JF, Chang Y, Chen HS, Chen R, Chen SM, Chen Y, Chen YX, Cheng J, Cheng ZK, Cherwinka JJ, Childress S, Chu MC, Chukanov A, Coelho JAB, Cummings JP, Dash N, De Rijck S, Deng FS, Ding YY, Diwan MV, Dohnal T, Dolzhikov D, Dove J, Dvořák M, Dwyer DA, Evans JJ, Feldman GJ, Flanagan W, Gabrielyan M, Gallo JP, Germani S, Gomes RA, Gonchar M, Gong GH, Gong H, Gouffon P, Graf N, Grzelak K, Gu WQ, Guo JY, Guo L, Guo XH, Guo YH, Guo Z, Habig A, Hackenburg RW, Hahn SR, Hans S, Hartnell J, Hatcher R, He M, Heeger KM, Heng YK, Higuera A, Holin A, Hor YK, Hsiung YB, Hu BZ, Hu JR, Hu T, Hu ZJ, Huang HX, Huang J, Huang XT, Huang YB, Huber P, Jaffe DE, Jen KL, Ji XL, Ji XP, Johnson RA, Jones D, Kang L, Kettell SH, Koerner LW, Kohn S, Kordosky M, Kramer M, Kreymer A, Lang K, Langford TJ, Lee J, Lee JHC, Lei RT, Leitner R, Leung JKC, Li F, Li HL, Li JJ, Li QJ, Li S, Li SC, Li SJ, Li WD, Li XN, Li XQ, Li YF, Li ZB, Liang H, Lin CJ, Lin GL, Lin S, Ling JJ, Link JM, Littenberg L, Littlejohn BR, Liu JC, Liu JL, Liu Y, Liu YH, Lu C, Lu HQ, Lu JS, Lucas P, Luk KB, Ma XB, Ma XY, Ma YQ, Mann WA, Marshak ML, Marshall C, Martinez Caicedo DA, Mayer N, McDonald KT, McKeown RD, Mehdiyev R, Meier JR, Meng Y, Miller WH, Mills G, Mora Lepin L, Naples D, Napolitano J, Naumov D, Naumova E, Nelson JK, Nichol RJ, O'Connor J, Ochoa-Ricoux JP, Olshevskiy A, Pahlka RB, Pan HR, Park J, Patton S, Pavlović Ž, Pawloski G, Peng JC, Perch A, Pfützner MM, Phan DD, Plunkett RK, Poonthottathil N, Pun CSJ, Qi FZ, Qi M, Qian X, Qiu X, Radovic A, Raper N, Ren J, Reveco CM, Rosero R, Roskovec B, Ruan XC, Sail P, Sanchez MC, Schneps J, Schreckenberger A, Shaheed N, Sharma R, Sousa A, Steiner H, Sun JL, Tagg N, Thomas J, Thomson MA, Timmons A, Tmej T, Todd J, Tognini SC, Toner R, Torretta D, Treskov K, Tse WH, Tull CE, Vahle P, Viren B, Vorobel V, Wang CH, Wang J, Wang M, Wang NY, Wang RG, Wang W, Wang W, Wang X, Wang Y, Wang YF, Wang Z, Wang Z, Wang ZM, Weber A, Wei HY, Wei LH, Wen LJ, Whisnant K, White C, Whitehead LH, Wojcicki SG, Wong HLH, Wong SCF, Worcester E, Wu DR, Wu FL, Wu Q, Wu WJ, Xia DM, Xie ZQ, Xing ZZ, Xu JL, Xu T, Xue T, Yang CG, Yang L, Yang YZ, Yao HF, Ye M, Yeh M, Young BL, Yu HZ, Yu ZY, Yue BB, Zeng S, Zeng Y, Zhan L, Zhang C, Zhang FY, Zhang HH, Zhang JW, Zhang QM, Zhang XT, Zhang YM, Zhang YX, Zhang YY, Zhang ZJ, Zhang ZP, Zhang ZY, Zhao J, Zhou L, Zhuang HL. Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments. PHYSICAL REVIEW LETTERS 2020; 125:071801. [PMID: 32857527 DOI: 10.1103/physrevlett.125.071801] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 06/13/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13 eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.
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Liu YS, Zhang YY, Xing T, Li JL, Wang XF, Zhu XD, Zhang L, Gao F. Glucose and lipid metabolism of broiler chickens fed diets with graded levels of corn resistant starch. Br Poult Sci 2020; 61:599-607. [PMID: 32456457 DOI: 10.1080/00071668.2020.1774511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
1. The aim of this study was to investigate the effects of graded levels of dietary corn resistant starch (RS) on glucose and lipid metabolism of broilers. 2. A total of 320 male broiler chicks (Arbor Acres, one-day-old) were randomly allocated to five dietary treatments, including a corn-soybean control diet, a corn-soybean based diet containing 20% corn starch, and three diets containing 4%, 8% and 12% RS by replacing corn starch with 6.67%, 13.33% and 20% Hi-Maize® 260 (identified as control, RS1, RS2, RS3 and RS4, respectively). Each treatment contained eight replicates with eight birds, and the experiment lasted 42 days. 3. Birds fed RS diets showed lower (P < 0.05) concentrations of serum low-density lipoprotein cholesterol and non-esterified fatty acid (NEFA) at d 21 and 42 of age, compared to the control. Lower (P < 0.05) hepatic apolipoprotein B concentration and citrate synthase (CS) activity, as well as a higher (P < 0.05) glycogen synthase (GS) concentration were observed in birds fed RS diets than those in the control group at d 21 of age. Consuming RS diets linearly increased (P < 0.01) serum glucose concentration, and linearly decreased (P < 0.01) NEFA concentrations in broilers at d 21 and 42 of age. Liver GS concentration and activities of hexokinase, pyruvate and CS were linearly increased (P < 0.01) in broilers at d 21 of age, but were linearly decreased (P < 0.05) in birds at d 42 of age in response to the increase of dietary RS levels. Feeding RS diets linearly decreased (P < 0.05) mRNA expressions of PC, PPARα and CPT-1 at d 21 of age and the mRNA expressions of SREBP-1 c, ChREBP, ACC and FAS at d 42 of age, and linearly increased (P < 0.05) the mRNA expressions of PEPCK, PC, LKB1, AMPKα1, PPARα, CPT-1 and L-FABP at d 42 of age. 4. Feeding broilers with diets containing higher concentration of RS promoted hepatic lipolysis and gluconeogenesis through activated AMPK signalling pathway and accelerated whole-body energy expenditures in the grower phase.
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Lv YQ, Ji S, Chen X, Xu D, Luo XT, Cheng MM, Zhang YY, Qu XL, Jin Y. Effects of crocin on frozen-thawed sperm apoptosis, protamine expression and membrane lipid oxidation in Yanbian yellow cattle. Reprod Domest Anim 2020; 55:1011-1020. [PMID: 32533872 DOI: 10.1111/rda.13744] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 06/01/2020] [Indexed: 12/01/2022]
Abstract
Glycerol is used as a bovine semen osmotic cryoprotectant that greatly improves the quality of frozen and thawed bovine sperm. However, high glycerol concentrations can have a toxic effect on frozen and thawed bovine sperm. Therefore, this experiment investigated the effect of replacing a portion of the glycerol in a cryoprotectant solution with crocin on the sperm apoptosis, protamine deficiency and membrane lipid oxidation of frozen and thawed Yanbian yellow cattle sperm. The experiment included a control group (6% glycerol) and four treatment groups: I (3% glycerol), II (3% glycerol +0.5 mM crocin), III (3% glycerol + 1 mM crocin) and IV (3% glycerol + 2 mM crocin). Computer assisted semen analysis was used to detect sperm motility, Hoechst 33,342, propidium iodide, and JC-1 staining were used to analyse sperm viability and mitochondrial membrane potential, chromomycin A3 staining was used to detect protamine deficiency and DNA damage, flow cytometry was used for sperm membrane lipid disorder detection and analysis, and real-time quantitative RT-qPCR was used to detect the mRNA expression levels of protamine-related genes (PRM2, PRM3), sperm acrosome-associated genes (SPACA3), oxidative stress-related genes (ROMO1) and apoptosis-related genes (BCL2, BAX). Compared to the control group, replacing a portion of glycerol with 1 mM crocin significantly improved sperm motility, plasma membrane integrity, membrane lipid disorders (p < .05) and viability, mitochondrial membrane potential, protamine deficiency (p < .01). The expression level of PRM2, PRM3, SPACA3 and BCL2 significantly increased (p < .05), while the expression levels of ROMO1 and BAX significantly decreased (p < .05). Accordingly, the BCL2/BAX ratio significantly increased (p < .05). In summary, the substitution of a portion of glycerol with crocin in cryoprotective solution improved the quality of Yanbian yellow cattle sperm after freezing and thawing.
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Li X, Su JZ, Zhang YY, Zhang LQ, Zhang YQ, Liu DG, Yu GY. [Inflammation grading and sialoendoscopic treatment of 131I radioiodine-induced sialadenitis]. JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2020; 52:586-590. [PMID: 32541997 DOI: 10.19723/j.issn.1671-167x.2020.03.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To investigate the inflammation grading of 131I radioiodine-induced sialadenitis based upon sialoendoscopic and sialographic appearances, and to evaluate the results of sialoendoscopic intervention. METHODS The patients diagnosed with 131I radioiodine-induced sialadenitis and underwent sialoendoscopic exploration and intervention procedures in Peking University Hospital of Stomatology from Nov. 2012 to Oct. 2018 were included in this study. The appearances of sialogaphy and sialoendoscopy were analyzed and classified. The treatment options included irrigation with saline and dexamethasone and mechanical dilatation by sialoendoscope. The patients were followed up after treatment. RESULTS Forty-two patients with 131I radioiodine-induced sialadenitis were included. There were 5 males and 37 females, with a male-to-female ratio of 1 ∶7.4. Symptoms included recurrent swelling and pain in the parotid glands, and dry mouth. Sialography showed stenosis in the main duct,and in some cases nonvisua-lization of the branches. Sialoendoscopy showed narrowing of the main duct, and the branch duct atresia was seen. The appearances of sialogaphy and sialoendoscopy were analyzed and classified into 3 groups: (1) Mild inflammation: stenosis and ectasia occurred in the main duct, whereas the 0.9 mm sialoendoscope could pass through easily. (2) Moderate inflammation: one point of severe stricture could be seen in the main duct where 0.9 mm sialoendoscope could not be passed through. (3) Severe inflammation: two points or more of severe strictures or diffused strictures occurred in the main duct. Thirty-three patients with 65 affected glands were examined by both sialography and sialoendoscopy. Eight glands were classified as mild inflammation, 23 glands moderate inflammation, and 34 glands severe inflammation. The duration of follow-up ranged from 3-72 months. The clinical results were evaluated as good in 22 glands, fair in 22 glands, and poor in 19 glands, with an overall effective rate of 69.8% (44/63). CONCLUSION The clinical, sialographic and sialoendoscopic appearances of 131I radioiodine-induced sialadenitis showed their characteristics. We proposed an inflammation grading standard for the 131I radioiodine-induced sialadenitis based on the appearances of sialography and sialoendoscopy. Sialoendoscopy can significantly alleviate the clinical symptoms, which is an effective therapy, and better for early lesions.
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Li QQ, Wan KX, Xu MS, Wang LM, Zhang YY, Wang CT, Mao FX, Zhu JL, Pan ZM, Gao R. [The pH-Sensitive Potassium Channel TASK-1 Is a Chemosensor for Central Respiratory Regulation in Rats]. Mol Biol (Mosk) 2020; 54:457-468. [PMID: 32492009 DOI: 10.31857/s0026898420030106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 10/30/2019] [Indexed: 11/24/2022]
Abstract
TWIK-related acid-sensitive potassium channel-1 (TASK-1) is a "leak" potassium channel sensitive to extracellular protons. It contributes to setting the resting potential in mammalian neurons. TASK-1 channels are widely expressed in respiratory-related neurons in the central nervous system. Inhibition of TASK-1 by extracellular acidosis can depolarize and increase the excitability of these cells. Here we describe the distribution of TASK-1 in the rat brainstem and show that TASK-1 mRNAs are present in respiratory-related nuclei in the ventrolateral medulla, which have been proposed as neural substrates for central chemo-reception in rats. After inhalation of 8% CO2 for 30 and 60 min, TASK-1 mRNA levels in positive-expression neurons were remarkably upregulated. Injection of the TASK-1 blocker anandamide (AEA) into the rat lateral cerebral ventricle, showed a significant excitement of respiratory at 10 min posttreatment, with a marked decrease in inspiratory and expiratory durations and an increased frequency of respiration. We suggest that TASK-1 channel may serve as a chemosensor for in central respiration and may contribute to pH-sensitive respiratory effects. TASK-1 channel might be an attractive candidate for sensing H^(+)/CO2 in several respiratory-related nuclei in the brainstem. It is likely that TASK-1 participates in pH-sensitive chemical regulation in the respiratory center under physiological and pathological conditions.
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Deng WC, Li YS, Cheng XH, Ren GH, He HB, Zhou YB, Zhang YY, Hu BJ, Liu HQ, Lu SK, Li SM, Zhou XN. [Implications, spiritual characteristics and practical significance of Chinese schistosomiasis control culture]. ZHONGGUO XUE XI CHONG BING FANG ZHI ZA ZHI = CHINESE JOURNAL OF SCHISTOSOMIASIS CONTROL 2020; 32:222-224. [PMID: 32468781 DOI: 10.16250/j.32.1374.2020050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The culture of schistosomiasis control is specific in the history of Chinese culture. Broadly speaking, the culture of schistosomiasis control is a summary of specific social mood, social consciousness and material culture created by Chinese populations during the progress of schistosomiasis control since the founding of the People's Republic of China. Narrowly speaking, the culture of schistosomiasis control is the spiritual culture that is jointly created and nurtured by schistosomiasis control workers since the founding of the People's Republic of China. The spiritual features of Chinese schistosomiasis control culture are characterized by the patriotism and care about the people, the matter-to-fact attitude, the pioneering and enterprising spirit, and the spirit of sacrifice and dedication. The ultimate goal of the research on the culture of schistosomiasis control is to facilitate the achievement of the strategic goal of Healthy China 2030 as scheduled, accelerate the progress towards elimination of schistosomiasis, and to promote the sustainable development of schistosomiasis control in China.
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Tian C, Zhang YY, Liu ZX, Dayananda B, Fu XB, Yuan D, Tu ZB, Luo CP, Li JQ. Temporal niche patterns of large mammals in Wanglang National Nature Reserve, China. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e01015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Qian ZP, Mei X, Zhang YY, Zou Y, Zhang ZG, Zhu H, Guo HY, Liu Y, Ling Y, Zhang XY, Wang JF, Lu HZ. [Analysis of baseline liver biochemical parameters in 324 cases with novel coronavirus pneumonia in Shanghai area]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2020; 28:229-233. [PMID: 32270660 DOI: 10.3760/cma.j.cn501113-20200229-00076] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Objective: To summarize the clinical characteristics and liver biochemical parameters of 324 cases admitted with novel coronavirus pneumonia in Shanghai area. Methods: Clinical data and baseline liver biochemical parameters of 324 cases with novel coronavirus pneumonia admitted to the Shanghai Public Health Clinical Center from January 20, 2020 to February 24, 2020 were retrospectively analyzed. Patients were divided into two groups based on the status of illness: mild type (mild and typical) and severe type (severe and critical).The differences in clinical data and baseline liver biochemical parameters of the two groups were described and compared. The t-test and Wilcoxon rank-sum test were used for measurement data. The enumeration data were expressed by frequency and rate, and chi-square test was used. Results: Of the 324 cases with novel coronavirus pneumonia, 26 were severe cases (8%), with median onset of 5 days, 20 cases were HBsAg positive (6.2%), and 70 cases (21.6%) with fatty liver, diagnosed with X-ray computed tomography. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyl transferase (GGT), total bilirubin (TBil), albumin(ALB) and international normalized ratio (INR) of 324 cases at baseline were 27.86 ± 20.02 U/L, 29.33 ± 21.02 U/L, 59.93 ± 18.96 U / L, 39.00 ± 54.44 U/L, 9.46 ± 4.58 μmol / L, 40.64 ± 4.13 g / L and 1.02 ± 0.10. Of which, ALT was > than the upper limit of normal (> ULN), accounting for 15.7% (51/324). ALT and AST > ULN, accounting for 10.5% (34/324). ALP > ULN, accounting for 1.2% (4/324). ALP and GGT > ULN, accounting for 0.9% (3/324). INR > ULN was lowest, accounting for 0.6% (2/324). There were no statistically significant differences (P > 0.05) in ALT [(21.5 vs. 26) U / L, P = 0.093], ALP [(57 vs.59) U/L, P = 0.674], and GGT [(24 vs.28) U/L, P = 0.101] between the severe group and the mild group. There were statistically significant differences in AST (23 U/L vs. 34 U/L, P < 0.01), TBil (10.75 vs. 8.05 μmol / L, P < 0.01), ALB (35.79 ± 4.75 vs. 41.07 ± 3.80 g/L, P < 0.01), and INR (1.00 vs. 1.04, P < 0.01). Conclusion: The baseline liver biochemical parameters of 324 cases with novel coronavirus pneumonia in Shanghai area was comparatively lower and the liverinjury degree was mild, and the bile duct cell damage was rare.
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Zhang YY, Li ZD, Jiang N, Wan PX, Deng CB, Su WR, Zhuo YH. [The effects and mechanism of baicalin in a mouse acute hypertensive glaucoma model]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2020; 56:376-382. [PMID: 32450671 DOI: 10.3760/cma.j.cn112142-20200107-00011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the potential neuroprotection effects and associated mechanism of baicalin in a rodent acute hypertensive glaucoma model and oxygen-glucose deprivation/reperfusion (OGD/R) induced retinal ganglion cell (RGC) injury. Methods: Experiment research. A rapid and substantial elevation of intraocular pressure was performed to establish an acute hypertensive glaucoma model, and retinal thickness was assessed at 1, 3, 5, and 7 days. The mice were then randomly divided into three groups: normal control group, hypertension group, and baicalin (50 mg/kg) for hypertension group. The effects of baicalin on the RGCs were evaluated by retrograde transporting of Fluoro-Gold. The mRNA levels of tumor necrosis factor-α, interleukine-1β (IL-1β), and inducible nitric oxide synthase were detected by real-time PCR, and the protein levels were measured by Western blot in the retina tissue of acute hypertensive glaucoma model. Purified primary RGC survival under OGD/R stress was measured by flow cytometry, which was also performed to measure the survival rate of RGCs pretreated by different doses of baicalin (2.5 μmol/L, 5.0 μmol/L, and 10.0 μmol/L). The effects of baicalin on primary RGCs co-cultured with mouse microglia cell line BV2 were evaluated by flow cytometry. The cytokine IL-1β in the culture supernatant was measured by immunochemical analyses. Statistical analysis was performed using analysis of variance. Results: Retinal tissue injuries and RGC loss were observed both in vivo and in vitro. Retinal thickness was decreased to 87.32%±0.94% at 3 days (t=6.73, P<0.01), 74.86%±2.43% at 5 days (t=13.40, P<0.01), and 63.53%±2.15% at 7 days (t=19.46, P<0.01). Treatment of 50 mg/kg baicalin significantly promoted the RGC survival from 61.32%±5.94% to 89.93%±10.08% (t=4.84, P<0.01). Baicalin alleviated the retinal damages by suppressing the expression of inflammatory cytokines as revealed by Western blot and real-time PCR. In vitro the RGC survival under OGD/R stress was increased from 51.53%±1.36% to 69.37%±7.09% and 66.23%±4.25% with 5.0, 10.0 μmol/L baicalin administration (t=5.50, 4.53; both P<0.01). BV2 under OGD/R stress did extra damage to RGCs, and baicalin could reverse the damages and increase the survival from 69.37%±7.09% to 73.00%±5.20% (t=2.82, P=0.048) by reducing the release of IL-1β [(39.97±8.76) pg/ml vs. (61.33±5.78) pg/ml, t=4.19, P=0.010]. Conclusion: Baicalin could alleviate retina tissue injury directly and promote the survival of RGCs by downregulating the expression of inflammatory cytokines and protecting RGCs from ischemia reperfusion injury. (Chin J Ophthalmol, 2020, 56: 376-382).
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Li HW, Yang DH, Zhan XQ, Zhong LJ, Zhang YY, Wang YS, Chen ZM. [Comparison of nucleic acid detection methods in pharyngeal swabs of Mycoplasma pneumoniae infection in children]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2020; 58:403-407. [PMID: 32392957 DOI: 10.3760/cma.j.cn112140-20191216-00813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the value of nucleic acid detection methods in pharyngeal swabs in the etiological diagnosis of Mycoplasma pneumoniae (MP) infection in children. Methods: Four hundred and fifty-four (male 210, female 244) children with pneumonia in Department of Pulmonology, Children's Hospital of Zhejiang University School of Medicine were enrolled from July, 2018 to October, 2018. Pharyngeal swabs and venous blood were obtained on the first or the second day after hospitalization. Fluorescence detection quantitative amplification of DNA, thermostatic amplification of RNA, MP culture and MP-IgM were used to detect MP simultaneously. MP infection is diagnosed if MP culture is positive or the two of the other three methods are positive. Pharyngeal swabs were acquired and detected using fluorescence quantitative amplification of DNA, thermostatic amplification of RNA and MP culture again for children with confirmed MP infection before discharge. The detection rates and quantitative changes of the three methods were compared, and χ(2) test was used for comparison among groups. Results: A total of 454 hospitalized children with pneumonia were included in this study. The detection rates of fluorescence quantitative amplification of DNA, thermostatic amplification of RNA, MP culture and MP-IgM IgM were 43.6% (198/454), 43.2% (196/454), 40.0% (180/454) and 30.6% (139/454) respectively. The difference of detection rates of the four methods was statistically significant (χ(2)=20.8, P<0.05),but no significant difference between the detection rates of fluorescence quantitative amplification of DNA and thermostatic amplification of RNA was found (χ(2)=0.018, P=0.900). They both had higher detection rates than MP-IgM or MP culture. MP infection is diagnosed if MP culture is positive or the two of the other three methods are positive, and two hundred and nine children were diagnosed as MP infection. In the second test of MP infection in 209 children before discharge, the positive rate of MP culture was 67.5% (141/209), with 39.4% (13/33) changed from negative to positive, and 27.3% (48/176) changed from positive to negative. The positive rate of thermostatic amplification of RNA was 82.3% (172/209), with 16.2% (31/191) turned from positive to negative, and 66.7% (12/18) turned from negative to positive. The positive rate of fluorescence quantitative amplification of DNA was 67.0% (140/209), with 52.9% (18/34) cases changed from negative to positive, and 30.3% (53/175) cases changed from positive to negative. MP-DNA load decreased in 141 cases (67.5%) and increased in 68 cases (32.5%) in the second test among the positive samples tested by fluorescence quantitative amplification of DNA. The detection rates of the four methods in the non-severe group and the severe group were similar, and the differences among the groups were not statistically significant (all P>0.05). In the second test, the proportion of changing from negative to positive in the severe group was higher than that in the non-severe group, but only the difference in the thermostatic amplification of RNA was statistically significant (P=0.038) and the cases of changing from negative to positive of thermostatic amplification of RNA in the severe group and non-severe group are 7 and 5 respectively. Conclusions: The methods of pharyngeal swab nucleic acid detection have high sensitivity and application value in the etiological diagnosis of acute MP infection in children. The results of fluorescence quantitative amplification of DNA and thermostatic amplification of RNA are highly consistent, and they are both more advantageous than MP-IgM. Repeated testing in the acute phase is helpful to find MP infection children whose first test is negative. The load of MP-DNA did not decrease in some children in the acute stage after antibiotic treatment.
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Qian K, Gao L, Chen X, Li H, Zhang S, Zhang XL, Zhu S, Yan J, Bao D, Cao L, Shi JA, Lu J, Liu C, Wang J, Qian T, Ding H, Gu L, Zhou W, Zhang YY, Lin X, Du S, Ouyang M, Pantelides ST, Gao HJ. Air-Stable Monolayer Cu 2 Se Exhibits a Purely Thermal Structural Phase Transition. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1908314. [PMID: 32239583 DOI: 10.1002/adma.201908314] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/09/2020] [Accepted: 03/03/2020] [Indexed: 06/11/2023]
Abstract
Materials possessing structural phase transformations exhibit a rich set of physical and chemical properties that can be used for a variety of applications. In 2D materials, structural transformations have so far been induced by strain, lasers, electron injection, electron/ion beams, thermal loss of stoichiometry, and chemical treatments or by a combination of such approaches and annealing. However, stoichiometry-preserving, purely thermal, reversible phase transitions, which are fundamental in physics and can be easily induced, have not been observed. Here, the fabrication of monolayer Cu2 Se, a new 2D material is reported, demonstrating the existence of a purely thermal structural phase transition. Scanning tunneling microscopy, scanning transmission electron microscopy, and density functional theory (DFT) identify two structural phases at 78 and 300 K. DFT calculations trace the phase-transition mechanism via the existence/absence of imaginary (unstable) phonon modes at low and high temperatures. In situ, variable-temperature low-energy electron diffraction patterns demonstrate that the phase transition occurs across the whole sample at ≈147 K. Angle-resolved photoemission spectra and DFT calculations show that a degeneracy at the Γ point of the energy bands of the high-temperature phase is lifted in the low-temperature phase. This work opens up possibilities for studying such phase transitions in 2D materials.
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Zhang YY, He HJ, Wang GW. [Renal mixed epithelial and stromal tumor (MEST) family: a clinicopathological study of 9 cases]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2020; 49:262-264. [PMID: 32187899 DOI: 10.3760/cma.j.issn.0529-5807.2020.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Zhang YY, Li GH. [Comparison of the composition of DJ tube encrustation and original stone and analysis of its causes]. ZHONGHUA YI XUE ZA ZHI 2020; 100:1084-1086. [PMID: 32294872 DOI: 10.3760/cma.j.cn112137-20190718-01593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Objective: To compare the composition of DJ tube encrustation and original stone, and to discuss the causes and prevention of encrustations. Methods: Twenty-five patients with DJ tube encrustation (1 case of INLAY OPTIMA(®) tube, Bard Medical, 16 cases of Universa(®) Firm tube, Cook Medical, 8 cases of Polaris™ Loop tube, Boston Scientific) in our institution from Januarry 2018 to April 2019 wereretrospective analyzed. Stones and encrustations were analyzed using the Fourier transform infrared spectroscopy analysis system to compare the differences in composition. Results: 76% (19/25) patients had the exact same DJ tube encrustations composition as the original stone component; 24% (6/25) patients had DJ tube encrustation and original stone composition inconsistent (5 cases of calcium oxalate stone, 1 case of apatite carbonate.) It maybe related to the control of urinary tract infection after ureteral obstruction. The earliest DJ tube with encrustation was a pre-expansion tube before flexible-ureteroscopy, and the indwelling time was only 18 days. Conclusions: DJ tubes of different brands and models have the risk of formation of encrustation. Most of the encrustation has the same composition as the original stone. The prevention of DJ tube scorpion can be started from: (1) removing the DJ tube within 6 weeks or replace it regularly when necessary; (2) selecting the appropriate tube including diameter and model; (3) actively controlling urinary tract infection; (4) treating the metabolic diseases, such as hypercalcemia, hyperuricemia, et al, and providing personalized guidance for each patient.
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Guo H, Zhang R, Li H, Wang X, Lu H, Qian K, Li G, Huang L, Lin X, Zhang YY, Ding H, Du S, Pantelides ST, Gao HJ. Sizable Band Gap in Epitaxial Bilayer Graphene Induced by Silicene Intercalation. NANO LETTERS 2020; 20:2674-2680. [PMID: 32125162 DOI: 10.1021/acs.nanolett.0c00306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Opening a band gap in bilayer graphene (BLG) is of significance for potential applications in graphene-based electronic and photonic devices. Here, we report the generation of a sizable band gap in BLG by intercalating silicene between BLG and Ru substrate. We first grow high-quality Bernal-stacked BLG on Ru(0001) and then intercalate silicene to the interface between the BLG and Ru, which is confirmed by low-energy electron diffraction and scanning tunneling microscopy. Raman spectroscopy shows that the G and 2D peaks of the intercalated BLG are restored to the freestanding-BLG features. Angle-resolved photoelectron spectroscopy measurements show that a band gap of about 0.2 eV opens in the BLG. Density functional theory calculations indicate that the large-gap opening results from a cooperative contribution of the doping and rippling/strain in the BLG. This work provides insightful understanding on the mechanism of band gap opening in BLG and enhances the potential of graphene-based device development.
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Yang S, Zhang YY, Zhao WL, Wei CG, Chen T, Li MJ, Tan SX, Shen JK. [The clinical decision-making value of prostate specific antigen and its derived indicators in prostate imaging reporting and data system version 2 3 lesions]. ZHONGHUA YI XUE ZA ZHI 2020; 100:997-1001. [PMID: 32294856 DOI: 10.3760/cma.j.cn112137-20190815-01814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Objective: To explore the decision-making value of clinical data in prostate imaging reporting and data system version 2 (PI-RADS V2) 3 lesions, and to compare the diagnostic value of related data for prostate cancer (PCa) and clinically PCa(csPCa). Methods: From March 2016 to October 2018,a subset of 121 men with 121 PI-RADS 3 index lesions were retrospectively analyzed. There were 31 PCa lesions and 14 csPCa lesions, aged from 46 to 91 years with a mean age of (71±9) years. The clinical data of the age, prostate specific antigen (PSA), free PSA (fPSA), f/tPSA, PSA density (PSAD) and prostate volume (PV) were compared between PCa group and non-PCa group, csPCa group and non-csPCa group using univariate analysis, respectively.The receiver operating characteristic (ROC) curve was used to evaluate the efficiency of statistically data in detecting PCa and csPCa in men with PI-RADS 3 index lesions. Results: The differences of PSA, f/tPSA and PSAD were all statistically significant (Z=-2.004, -2.527, -2.623, all P<0.05) between PCa group and non-PCa group, and they were all also statistically significant(Z=-2.415, -2.158, -2.870, all P<0.05) between csPCa group and non-csPCa group. Both PSAD had the best diagnostic efficiency, the ROC curve of detecting PCa and csPCa was 0.658 and 0.736, respectively. If used PSAD>0.20 μg·L(-1)·ml(-1) as the biopsy threshold, the sensitivity, specificity, positive predictive value and negative predictive value of csPCa were 78.6%, 58.9%, 20.0%, 95.4%, and 54.5% (66/121) of the enrolled men can avoid biopsy, resulting only 3 cases of csPCa missed. Conclusion: PSA, f/tPSA, PSAD, especially PSAD can improve the detection efficiency of PCa,especially csPCa in PI-RADS 3 lesions, assisting clinical decision-making.
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Shen MM, Zhang LL, Chen YN, Zhang YY, Han HL, Niu Y, He JT, Zhang YL, Cheng YF, Wang T. Effects of bamboo leaf extract on growth performance, meat quality, and meat oxidative stability in broiler chickens. Poult Sci 2020; 98:6787-6796. [PMID: 31289827 PMCID: PMC8913974 DOI: 10.3382/ps/pez404] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 06/19/2019] [Indexed: 02/06/2023] Open
Abstract
This study was conducted to investigate the effects of dietary bamboo leaf extract (BLE) on growth performance, meat quality, oxidative stability, and nuclear factor erythroid 2-related factor 2 (Nrf2) related gene expression of breast meat in broilers. A total of 576 one-day-old male Arbor Acres broilers were divided into 6 groups. The control group (CTR) was fed basal diet, while BLE1, BLE2, BLE3, BLE4, and BLE5 were fed basal diet supplemented with 1.0, 2.0, 3.0, 4.0, and 5.0 g BLE per kg feed, respectively. Compared with the CTR group, BLE2 and BLE5 increased average daily feed intake from 1 to 21 D and 22 to 42 D (P < 0.05), BLE1 and BLE2 improved average daily gain (ADG) and feed to gain ratio from 22 to 42 D (P < 0.05). Throughout the trial period, the highest body weight and favorable ADG and feed to gain ratio were observed in the BLE2 group. The drip loss at 24 h and pH at 45 min postmortem of breast meat were linearly improved by BLE supplementation (P < 0.05). Shear force was significantly lower in BLE2 and BLE3 than that in CTR group. Increasing supplementation of BLE linearly improved free radical scavenging capacity and decreased malondialdehyde content of breast meat during 12 D of storage (P < 0.05). Total antioxidant capacity and glutathione peroxidase activity were linearly increased by BLE supplementation (P < 0.05). Compared with the CTR group, the mRNA expression of Nrf2 and glutathione peroxidase in BLE3, BLE4, and BLE5 groups was significantly promoted, and glutathione S-transferase gene expression was increased in BLE2, BLE4, and BLE5 (P < 0.05). The highest (P < 0.05) heme oxygennase-1 gene expression was observed in BLE5. In conclusion, broiler supplemented with BLE improved growth performance and meat quality, BLE supplementation might activate Nrf2 pathway to alleviate lipid oxidation and increase antioxidant capacity of breast meat. The dosage of 2.0 to 3.0 g/kg BLE in broiler diet was recommanded.
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Zhang YY, Ma QF, Chen XX, Ying CH, Ma YL, Li P, Gao L, Song HH, Yin QP. [Value of contrast - enhanced ultrasonography and acoustic radiation force impulse elastography in identification of boundary range and viability of hepatic alveolar echinococcosis]. ZHONGGUO XUE XI CHONG BING FANG ZHI ZA ZHI = CHINESE JOURNAL OF SCHISTOSOMIASIS CONTROL 2020; 32:91-93. [PMID: 32185935 DOI: 10.16250/j.32.1374.2018087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To investigate the biologic viability and boundary range of hepatic alveolar echinococcosis (HAE) by the contrast-enhanced ultrasonography (CEUS) and acoustic radiation force impulse elastography (ARFI). METHODS Totally 27 HAE patients confirmed by pathology underwent CEUS and ARFI examinations. RESULTS Gray scale sonography of HAE showed unclear boundary, inhomogeneous, and middle hyperechoic nodules, and the maximum area was (6.08 ± 4.47) cm2 in 27 lesions. CEUS of HAE showed non-enhancement in three phases and black hole sign. Circumferential enhancement on the pe riphery of the lesion was synchronized with the liver parenchyma and showed "fast in and slow out". The maximum area was (8.87 ± 4.83) cm2. The area of ECUS was larger than gray scale sonography in HAE (t = 2.20, P = 0.03). The mean shear wave velocities (SWVs) of the interior, the boundary range, and the surrounding liver tissues of HAE were statistically different by ARFI (F = 84.538, P < 0.001), and the interior had the highest values. CONCLUSIONS CEUS and ARFI examinations can detect the biologic viability and boundary range of migrating zone around HAE, which is valuable for guiding treatment, judging curative effect, and predicting prognosis.
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Zhang YY, Li HW, Chen ZM. [Research progress in the application of anti-IgE antibody for allergic asthma in school-age children]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2020; 58:255-258. [PMID: 32135605 DOI: 10.3760/cma.j.issn.0578-1310.2020.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wu R, Bao DL, Yan L, Wang Y, Ren J, Zhang YF, Huan Q, Zhang YY, Du S, Pantelides ST, Gao HJ. Direct Visualization of Hydrogen-Transfer Intermediate States by Scanning Tunneling Microscopy. J Phys Chem Lett 2020; 11:1536-1541. [PMID: 32011142 DOI: 10.1021/acs.jpclett.0c00046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Hydrogen atoms bonded within molecular cavities often undergo tunneling or thermal-transfer processes that play major roles in diverse physical phenomena. Such transfers may or may not entail intermediate states. The existence of such fleeting states is typically determined by indirect means, while their direct visualization has not been achieved, largely because their concentrations under equilibrium conditions are negligible. Here we use density-functional-theory calculations and scanning-tunneling-microscopy (STM) image simulations to predict that, under specially designed nonequilibrium conditions of voltage-enhanced high transfer rates, the cis-intermediate of the two-hydrogen transfer process in metal-free naphthalocyanine molecules adsorbed on Ag(111) surfaces would be visualizable in a composite image of double-C morphology. As guided by the theoretical predictions, at adjusted scanning temperature and bias, STM experiments achieve a direct visualization of the cis-intermediate. This work demonstrates a practical way to directly visualize elusive intermediates, which enhances understanding of the quantum dynamics of hydrogen atoms.
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Kong L, Huang Z, Zhang SS, Song J, Zhang YY, Bai XY, Yang JX, Li L. Correction: A facile strategy to realize a single/double photon excitation-dependent photosensitizer for imaging-guided phototherapy against HeLa cancer cells at separate irradiation channels. Chem Commun (Camb) 2020; 56:1899. [PMID: 32016277 DOI: 10.1039/d0cc90057e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Correction for 'A facile strategy to realize a single/double photon excitation-dependent photosensitizer for imaging-guided phototherapy against HeLa cancer cells at separate irradiation channels' by Lin Kong et al., Chem. Commun., 2020, 56, 571-574.
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Zhu L, Jin X, Zhang YY, Du S, Liu L, Rajh T, Xu Z, Wang W, Bai X, Wen J, Wang L. Visualizing Anisotropic Oxygen Diffusion in Ceria under Activated Conditions. PHYSICAL REVIEW LETTERS 2020; 124:056002. [PMID: 32083924 DOI: 10.1103/physrevlett.124.056002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/16/2019] [Accepted: 01/08/2020] [Indexed: 06/10/2023]
Abstract
Oxygen reactivity plays a key role in the performance of ceria-based catalysts. Aberration-corrected transmission electron microscopy and molecular dynamics simulations were used to study the oxygen atom diffusion in ceria under activated conditions. Reactive oxygen atom and its real-time diffusion were visualized. The interplay between cerium and oxygen atoms originating from a Coulomb interaction was revealed by the out-of-plane buckling of cerium atoms associated with oxygen transport. Anisotropic oxygen atom diffusion that depends on crystal orientations was discovered, demonstrating a preferential [001] crystallographic diffusion pathway. These findings reveal prospects for applications of anisotropic orientation-relevant fluorite-structured oxides.
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Zhang YY, Liu XG, Yu N, Zhao ZH, Yang QL, Gao YL, Fan C, Dong JH. [Effects of fertilizer application on yield and fertilizer utilization of Coffea arabica in southwest dry-hot region of China under different shading levels]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2020; 31:515-523. [PMID: 32476345 DOI: 10.13287/j.1001-9332.202002.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The fertilizer and shading management of Coffea arabica in dry-hot area is extensive, resulting in lower yield and fertilizer utilization efficiency. A field experiment was carried out to find the coupling mode of shading and fertilizer for fertilizer-saving and high yield of C. arabica in dry-hot region. Four shading levels (100% NR, 75% NR, 60% NR, 45% NR, NR was natural radiation) and four fertilizer levels (No fertilization and 666.67, 1000, 1333.33 kg·hm-2) were set to examine the effects of different radiations and fertilizer treatments on canopy structure, yield, ferti-lizer use efficiency, soil nutrient content and microbial biomass carbon of C. arabica. The results showed that canopy structure, yield, fertilizer use efficiency, soil nutrient content and microbial biomass carbon were significantly affected by shading and fertilizer treatments. Soil nutrient content and microbial biomass carbon decreased with the increases of shading levels. Soil nutrient content increased with the increases of fertilizer application, while microbial biomass carbon increased first and then decreased, with a peak at the rate of 1000 kg·hm-2(200.30 mg·kg-1). Shading and fertilizer had significant effects on the canopy structure including leaf area index and openness. There were significant negative correlations of leaf area index with openness, gap fraction, total fixed-point factor and total radiation under canopy. Results of response surface analysis and spatial analysis showed that the combination of shading level and fertilizer application were 80% NR and 666.67 kg·hm-2, 79% NR and 1286.81 kg·hm-2, 79% NR and 967.74 kg·hm-2, 82% NR and 1075.27 kg·hm-2, respectively, when partial fertilizer productivity, yield, fertilizer agronomic efficiency and yield increase of fertilizer reached the maximum. The ranges of shading and fertilizer were 68%-77% NR and 946.24-1178.79 kg·hm-2 when the yield, agronomic efficiency and yield increasing rate by fertilizer reached 80% of the maximum value. In this experiment, the optimum combination of shading level and fertilizer application was 75% NR and 1000 kg·hm-2.
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Kong L, Huang Z, Zhang SS, Song J, Zhang YY, Bai XY, Yang JX, Li L. A facile strategy to realize a single/double photon excitation-dependent photosensitizer for imaging-guided phototherapy against HeLa cancer cells at separate irradiation channels. Chem Commun (Camb) 2020; 56:571-574. [DOI: 10.1039/c9cc07968h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A facile strategy has been proposed to realize two-photon phototherapy against HeLa cancer cells with simultaneous one-photon fluorescence imaging modality at separate irradiation channels.
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Gao L, Sun JT, Sethi G, Zhang YY, Du S, Liu F. Orbital design of topological insulators from two-dimensional semiconductors. NANOSCALE 2019; 11:22743-22747. [PMID: 31774416 DOI: 10.1039/c9nr06859g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Two-dimensional (2D) materials have attracted much attention because they exhibit various intrinsic properties, which are, however, usually not interchangeable. Here we propose a generic approach to convert 2D semiconductors to 2D topological insulators (TIs) via atomic adsorption. The approach is underlined by an orbital design principle that involves introducing an extrinsic s-orbital state of the adsorbate into the intrinsic sp-bands of a 2D semiconductor, so as to induce s-p band inversion for a TI phase, as demonstrated by tight-binding model analyses. Based on first-principles calculations, we successfully apply this approach to convert CuS, CuSe and CuTe into TIs by adsorbing one adatom per unit cell of Na, Na0.5K0.5 and K as well as Rb and Cs. Moreover, if the chalcogens in the 2D semiconductor have a decreasing ability of accepting electrons, the adsorbates should have an increasing ability of donating electrons. Our findings open a new door to discovering TIs by predictive material design beyond finding preexisting TIs.
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Chen S, Li YX, Zhang NB, Huang JW, Hou HM, Ye SJ, Zhong T, Zeng XL, Fan D, Lu L, Wang L, Sun T, Fezzaa K, Zhang YY, Tang MX, Luo SN. Capture Deformation Twinning in Mg during Shock Compression with Ultrafast Synchrotron X-Ray Diffraction. PHYSICAL REVIEW LETTERS 2019; 123:255501. [PMID: 31922810 DOI: 10.1103/physrevlett.123.255501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 11/27/2019] [Indexed: 06/10/2023]
Abstract
Deformation twinning plays a vital role in accommodating plastic deformation of hexagonal-close-packed (hcp) metals, but its mechanisms are still unsettled under high strain rate shock compression. Here we investigate deformation twinning in shock-compressed Mg as a typical hcp metal with in situ, ultrafast synchrotron x-ray diffraction. Extension twinning occurs upon shock compression along ⟨112[over ¯]0⟩ and ⟨101[over ¯]0⟩, but only upon release for loading along ⟨0001⟩. Such deformation mechanisms are a result of the polarity of deformation twinning, which depends on directionality and relative magnitude of resolved shear stress and may be common for Mg and its alloys in a wide range of strain rates.
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