聚己内酯掺杂竹荪多糖的3D打印工艺及性能

3D打印技术在组织工程领域的应用日益受到重视,但聚己内酯(PCL)由于其亲水性和韧性的问题在此领域的应用受到了限制。为此,文中用竹荪提取的多糖物质对PCL进行复合改性,制备了多糖/PCL 3D打印支架,旨在改善其力学性能并提高其生物学性能以促进组织工程应用。通过拉伸试验表明,添加多糖后的PCL韧性明显提升且弹性模量更接近于骨组织。接触角试验表明,添加多糖后提高了表面的润湿性,接触角从92°降低至76°。经过体外细胞培养验证,添加多糖后生物相容性有所提高。研究表明,添加1%多糖后的改性支架表现出最优异的亲水性、韧性和生物相容性,且显著增强了成骨细胞的附着。

Anti-skin aging effects and bioavailability of collagen tripeptide and elastin peptide formulations in young and middle-aged women

Background:Collagen peptides(CP),including tripeptides and elastin peptides(EP),are known for their in vitro and in vivo anti-skin aging effects.Despite positive results in animal models,the combination effects of CP and EP and the bioavailability of CP in human studies,particularly in young and middle-aged women,remain underexplored.Objective:To evaluate the effects of an orally administered collagen drink combining CP and EP on the skin health of young and middle-aged women.Materials and Methods:A single-center,randomized,double-blind,parallel-controlled trial was conducted,utilizing the WONDERLABR fish collagen tripeptide beverage.Participants consumed the drink over an 8-week period.Results:Compared to the placebo group,the collagen drink group showed significant improvements in skin hydration(39.19%increase),transepidermal water loss(33.45%decrease),skin elasticity(25.37%increase),dermal collagen content(21.64%increase),pore size(7.94%decrease),wrinkle length(18.09%decrease),skin smoothness(2.85%improvement),and skin roughness(15.32%decrease).Overall pore volume decreased by 60%,and visual assessments indicated a decrease in skin luminosity by 15.20%and smoothness index by 22.55%.Mass spectrometry demonstrated a significant increase in collagen efficacy components,including blood pH and GPH levels(P<0.05).Conclusion:The study confirmed the combination nourishing and anti-skin aging effects of EP and CP on the skin of young and middle-aged women,demonstrating significant improvements in various skin parameters and good bioavailability of collagen peptides.

An artificial intelligence diabetes management architecture based on 5G

Along with the development of 5G network and Internet of Things technologies,there has been an explosion in personalized healthcare systems.When the 5G and Artificial Intelligence(Al)is introduced into diabetes management architecture,it can increase the efficiency of existing systems and complications of diabetes can be handled more effectively by taking advantage of 5G.In this article,we propose a 5G-based Artificial Intelligence Diabetes Management architecture(AIDM),which can help physicians and patients to manage both acute complications and chronic complications.The AIDM contains five layers:the sensing layer,the transmission layer,the storage layer,the computing layer,and the application layer.We build a test bed for the transmission and application layers.Specifically,we apply a delay-aware RA optimization based on a double-queue model to improve access efficiency in smart hospital wards in the transmission layer.In application layer,we build a prediction model using a deep forest algorithm.Results on real-world data show that our AIDM can enhance the efficiency of diabetes management and improve the screening rate of diabetes as well.

Smad8 is involvement in follicular development via the regulation of granulosa cell growth and steroidogenesis in mice

Background:SMAD family proteins(SMADs)are crucial transcription factors downstream of transforming growth factor beta(TGF-ß)/SMAD signaling pathways that have been reported to play a pivotal role in mammalian reproduction.However,the role of SMAD family member 8(SMAD8,also known as SMAD9),a member of the SMAD family,in mammalian reproduction remains unclear.Methods:We employed RNA interference techniques to knock down Smad8 expression in mouse granulosa cells(GCs)to investigate the effects of Smad8 on GC growth and steroidogenesis.Results:Our findings revealed a significant decrease in the proliferative capacity and a substantial increase in the apoptosis rate of GCs after transfection with Smad8-siRNA for 48 h.Subsequent hormone assays demonstrated a significant decrease in estradiol(E2)levels,whereas progesterone(P4)remained unchanged.Further mechanistic analysis showed that the mRNA expression of proliferating cell nuclear antigen(Pcna),Cyclin D2,cell cycle-dependent kinase 4(Cdk4),B-cell lymphoma-2(Bcl-2),estrogen receptor(Er),luteinizing hormone receptor(Lhr)and cytochrome P450 family 19 subfamily A member 1(Cyp19a1)significantly decreased.Conversely,the mRNA of cysteine aspartate proteinase 3(Caspase 3)significantly increased,wheras Bcl2-associated X(Bax),folliclestimulating hormone receptor(Fshr)and cytochrome P450 family 11 subfamily A member 1(Cyp11a1)remained unchanged compared to the controls.Conclusion:This study indicates that Smad8 knockdown inhibits cell proliferation,promotes apoptosis,reduces Er and Lhr transcription,and decreases E2 production in mouse GCs.These findings suggest that Smad8 may serve as a novel genetic marker for mammalian reproduction.

Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents

Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time.

The efficacy of a novel tomato extracts formulation on skin aging and pigmentation:A randomized,double-blind,parallel-controlled trial

Background:Oxidative stress is a significant factor in skin aging and pigmentation,which can be precipitated by various circumstances.Antioxidants and tyrosinase inhibitors,such as carotenoids,yeast extract(glutathione),sodium hyaluronate,astaxanthin,and niacin,can individually protect the skin against aging through distinct mechanisms.These mechanisms potentially enhance the skin barrier and improve signs of aging and pigmentation.However,the synergistic effects of these compounds,as found in a golden tomato extract formulation,have been scarcely explored.Objective:To evaluate the effects of an orally administered formulation on the skin aging and pigmentation.Material and Methods:In this study,a randomized,double-blind,parallel-controlled trial was conducted,utilizing the WONDERLAB?Tomato Niacinamide beverage.Out of all participants,62 volunteers completed the experiment and were included in the statistical analysis.Results:The results indicated that after eight weeks of consuming the research product,there were no significant changes in the skin indicators within the placebo group.In contrast,the treatment group receiving the sample formulation exhibited a 35.63%increase in stratum corneum hydration and a 29.39%reduction in transepidermal water loss(TEWL),suggesting enhanced skin hydration.Visual assessments revealed improvements in skin color and gloss index by 15.03%and 11.41%,respectively,in the treatment group.Furthermore,the skin gloss and individual typology angle(ITA)value increased by 18.59%and 6.36%,respectively,leading to a lighter skin tone.Significant enhancements were also observed in skin pigmentation,color uniformity,and redness.After eight weeks of intervention with the sample,blood levels of superoxide dismutase(SOD)and glutathione peroxidase(GPx)increased,while malondialdehyde(MDA)levels decreased.Conclusion:These findings confirm that continuous intake of the tomato extract formulation over eight weeks effectively improved the volunteers'skin whitening and hydration,and visibly brightened skin tone through an antioxidant mechanism.

Association of serum gamma-glutamyl transferase with treatment outcome in chronic hepatitis B patients

AIM:To investigate the association of serum gammaglutamyl transferase(GGT) levels with chronic hepatitis B infection and hepatitis B e antigen(HBe Ag) seroconversion.METHODS:A retrospective study was performed on clinical data collected from patients who had been positive for hepatitis B surface antigen for > 6 mo and who were antiviral-treatment na?ve(n = 215) attending the Hepatitis Clinic at Nanjing Drum Tower Hospital between August 2010 and December 2013. Healthy individuals without liver disease(n = 83) were included as controls. Patients were categorized into four groups based on disease status as recommended by the European Association for the Study of the Liver:immune tolerance(IT; n = 47),HBe Ag-positive hepatitis(EPH; n = 93),HBe Ag-negative hepatitis(ENH;n = 20),and inactive carrier(IC; n = 55). Prediction of complete response(CR) based on serum GGT was also examined in EPH patients(n = 33) treated for 48 wk with nucleos(t)ide analogue(NA) therapy,including lamivudine plus adefovir combination therapy(n = 20) or entecavir monotherapy(n = 13). CR was defined as a serum hepatitis B virus DNA level < 500 copies/m L and HBe Ag seroconversion by 48 wk of treatment. RESULTS:Serum GGT levels were significantly increased in EPH and ENH patients relative to the IT,IC,and healthy control groups(P < 0.01 for all). However,no significant difference in serum GGT levels was found between the EPH and ENH groups. Baseline serum GGT levels were significantly higher in patients who achieved CR(7/33; 21.2%) compared to patients in the non-CR group(26/33; 78.8%; P = 0.011). In addition,the decline in serum GGT was greater in CR patients compared to non-CR patients after 24 wk and 48 wk of treatment(P = 0.012 and P = 0.008,respectively). The receiver operating characteristic curve yielded a sensitivity of 85.71% and a specificity of 61.54% at a threshold value of 0.89 times the upper limit of normal for baseline serum GGT in the prediction of CR following NA therapy. CONCLUSION:Serum GGT is significantly elevated in EPH and ENH patients and is a potential biomarker for the prediction of HBe Ag seroconversion following NA therapy.

Experimental Study on the Effectiveness and Safety of Gardenia Blue Pigment on Anterior Capsule Staining

Objective: To explore the effect of gardenia blue pigment on the anterior capsule staining and its safety performance. Methods: In this study, New Zealand white rabbits were used as the research object to test the effect of gardenia blue pigment on the anterior capsule staining and anterior segment toxicity. In this study, gardenia blue stains of different concentrations (5%, 4%, 3%, 2%, 1%, 0.5%) were prepared to stain the anterior capsule of rabbit crystals, and the effect of the stain was observed to determine the optimal concentration of the stain. Twenty-seven healthy New Zealand white rabbits without eye disease were randomly divided into three groups: gardenia blue staining group;bio-blue positive drug group;physiological saline group. The intraocular pressure, anterior chamber inflammation, corneal endothelial injury, and anterior chamber angle pathological changes were measured in 1D, 7D, and 14D. Results: The results of this study showed that the effect of gardenia blue pigment on the anterior capsule of the lens was the best when the concentration of blue pigment was 2%. There was no change in intraocular pressure in the anterior chamber for a short period of time. There is no damage to the corneal endothelium. Conclusion: The results of this study show that the effect of gardenia blue pigment on the anterior capsule is best when the concentration of blue pigment is 2%, and the stain has no obvious toxic and side effects on the anterior segment of the eye.

Forest characteristics,population structure and growth trends of threatened relict Pseudotsuga forrestii in China

Pseudotsuga forrestii is a relict evergreen coniferous tree species in Pinaceae endemic to China.P.forrestii tree numbers have greatly decreased due to deforestation,over-utilization and habitat degradation.Here we clarify P.forrestii community types,structure,species diversity,seedling recruitments and growth trends.We identified four P.forrestii community types:(1)Pseudotsuga forrestii-Quercus guyavifolia-Acer davidii evergreen coniferous and broad-leaved mixed forest;(2)Pseudotsuga forrestii-Pinus yunnanensis-Quercus guyavifolia evergreen coniferous and broad-leaved mixed forest;(3)Pseudotsuga forrestii evergreen coniferous forest;(4)Pseudotsuga forrestii-Abies georgei var.smithii evergreen coniferous forest.P.forrestii forests are characterized by both warm temperate and temperate affinities.Simpson diversity,Pielou evenness,Shannon-Wiener diversity indices ranged from 0.75 to 0.76,0.74-0.81,and 1.62-1.93,respectively,with no significant differences among the four forest types.The forest stratification was multilayered.The canopy layer was generally 10-25 m tall,with the emergent layer reached 25-42 m.DBH and age structures of P.forrestii showed multimodal distributions.Its maximum age P.forrestii was 570 years with a DBH of 143 cm.The growth of annual ring width of P.forrestii was slow,and generally decreased with age,whereas the basal area at the breast height increased with age.Established seedlings/saplings were mainly found in unstable micro-habitats.Regeneration of P.forrestii depends on moderate natural disturbances.Finally,we provide recommendations for P.forrestii conservation.

沙库巴曲缬沙坦、达格列净和恩格列净治疗射血分数降低心力衰竭的成本-效用分析

目的 从我国卫生体系的角度出发,对比沙库巴曲缬沙坦、达格列净和恩格列净3种方案治疗射血分数降低心力衰竭(HFrEF)的成本-效用分析,为临床治疗药物的选择提供依据。方法 基于DAPA-HF和EMPEROR-Reduced 2项临床试验数据构建Markov模型,模拟HFrEF疾病发展状况,评价3种方案治疗HFrEF患者的成本-效用,并对结果进行敏感性分析。结果 与恩格列净组相比,达格列净组和沙库巴曲缬沙坦组的增量成本-效用比(ICUR)分别为20 248.63,23 860.98元/质量调整生命年(QALY);与达格列净组相比,沙库巴曲缬沙坦组的ICUR为28 423.95元/QALY,3组两两相比的ICUR均小于2021年1倍人均国内生产总值。概率敏感性分析显示,当意愿支付阈值超过30 000元/QALY时,沙库巴曲缬沙坦较达格列净、恩格列净方案具有经济性的概率为100%。结论 沙库巴曲缬沙坦在治疗HFrEF方面的经济性优于达格列净和恩格列净。

Neuro-11:a new questionnaire for the assessment of somatic symptom disorder in general hospitals

Background Somatic symptom disorder(SSD)commonly presents in general hospital settings,posing challenges for healthcare professionals lacking specialised psychiatric training.The Neuro-11 Neurosis Scale(Neuro-11)offers promise in screening and evaluating psychosomatic symptoms,comprising 11 concise items across three dimensions:somatic symptoms,negative emotions and adverse events.Prior research has validated the scale’s reliability,validity and theoretical framework in somatoform disorders,indicating its potential as a valuable tool for SSD screening in general hospitals.Aims This study aimed to establish the reliability,validity and threshold of the Neuro-11 by comparing it with standard questionnaires commonly used in general hospitals for assessing SSD.Through this comparative analysis,we aimed to validate the effectiveness and precision of the Neuro-11,enhancing its utility in clinical settings.Methods Between November 2020 and December 2021,data were collected from 731 patients receiving outpatient and inpatient care at Shenzhen People’s Hospital in China for various physical discomforts.The patients completed multiple questionnaires,including the Neuro-11,Short Form 36 Health Survey,Patient Health Questionnaire 15 items,Hamilton Anxiety Scale and Hamilton Depression Scale.Psychiatry-trained clinicians conducted structured interviews and clinical examinations to establish a gold standard diagnosis of SSD.Results The Neuro-11 demonstrated strong content reliability and structural consistency,correlating significantly with internationally recognised and widely used questionnaires.Despite its brevity,the Neuro-11 exhibited significant correlations with other questionnaires.A test-retest analysis yielded a correlation coefficient of 1.00,Spearman-Brown coefficient of 0.64 and Cronbach’sαcoefficient of 0.72,indicating robust content reliability and internal consistency.Confirmatory factor analysis confirmed the validity of the three-dimensional structure(p<0.001,comparative fit index=0.94,Tucker-Lewis index=0.92,root mean square error of approximation=0.06,standardised root mean square residual=0.04).The threshold of the Neuro-11 is set at 10 points based on the maximum Youden’s index from the receiver operating characteristic curve analysis.In terms of diagnostic efficacy,the Neuro-11 has an area under the curve of 0.67.

Chinese Population Reference Curves for Ultrasound-Measured Amniotic Fluid Deepest Vertical Pocket in Dichorionic Twin Pregnancies,and Their Associations With Pregnancy Outcomes

Objective:To establish the Chinese population's amniotic fluid deepest vertical pocket(DVP)reference curves for dichorionic twin pregnancies and to investigate DVP links with adverse perinatal outcomes.Methods:This retrospective cohort study,conducted at Peking University Third Hospital from August 2011 to December 2020,used data from 375 women aged 20 to 45 years who had dichorionic twin pregnancies that were confirmed through first-trimester ultrasound.After exclusions,reference curves were developed using 318 women with 3,299 DVP scans,and the data analyzed included maternal demographics,pregnancy outcomes,ultrasound measurements,and neonatal information.DVPs were assessed via ultrasound at regular intervals and grouped by gestational age(GA)for analyses.Linear mixed models were used to create amniotic fluid reference curves.Associations between abnormalities and adverse perinatal outcomes were examined using Chi-squared or Fisher's exact tests.Logistic regression provided both crude and adjusted odds ratios,adjusting for pre-pregnancy weight,age,ethnicity,parity,and conception mode.Significance was set at P<0.05 with 95%confidence intervals(CI),and the analyses were conducted using SPSS ver.26.0(IBM Corp.,Armonk,NY)and SAS ver.9.4(SAS Institute Inc.,Cary,NC,USA)software.Results:DVP increased from the first trimester to a maximum at 26 weeks(95%confidence interval(CI),2.7–8.3 cm for twin 1 and 2.8–7.9 cm for twin 2)and then decreased gradually toward term.Differences between twins 1 and 2 were significant after 26 weeks(95%CI for twin 1:5.3,5.5;95%CI for twin 2:4.4,4.5;P<0.010).Polyhydramnios of twin 1 increased the risk of large for GA.Oligohydramnios of twin 1 increased the risk of small for GA.Polyhydramnios of twin 2 increased the risk of small for GA,premature birth,and neonatal complications.Oligohydramnios of twin 2 increased the risk of preeclampsia,hypertensive disorder complicating pregnancy,and premature rupture of membranes.Conclusion:Reference curves for twin amniotic fluid volumes vary by GA and differ between twins,with potential implications for pregnancy outcomes.

超临界350MW循环流化床锅炉变负荷特性

随着可再生能源发电比重的增加,火电机组在深度调峰中的重要性日益突出,大幅度变负荷已成为运行常态。为了研究循环流化床(CFB)机组的深度变负荷特性,本文以河坡电厂超临界350 MW机组CFB锅炉为研究对象,分析了CFB机组变负荷时的床温、蒸汽参数以及污染物排放的变化。结果表明:床温与负荷成正相关,前后位置床温的差值相对较大,通过控制排渣量可显著调节床温;随着负荷变化,高温过热器出口蒸汽与高温再热器出口蒸汽的温度整体稳定,波动较小;60%~90%负荷升降负荷时,由于运行床温和二次风配比合理,NO_x排放质量浓度的变化范围分别为30~70 mg/m^3和20~50 mg/m^3,且中低负荷区间变负荷时NOx的原始生成量显著大于中高负荷;在参与深度调峰时负荷响应速度较快,机组升负荷速率为6 MW/min(1.71%/min),降负荷速率为4 MW/min(1.14%/min)。总体而言,超临界350 MW机组CFB锅炉变负荷范围广,低负荷稳定性强,NOx原始排放较低。

加工工艺对速食小米粥物理性质的影响

随着生活节奏的加快,速食粥越来越受人们的青睐,对速食粥类产品物理品质的改善将是研究的重点。笔者以小米为原材料,采用高压蒸煮与冷冻干燥的方法研制速食小米粥,通过响应面分析方法,研究加工过程中料液比、煮粥时间与冻干温度对速食小米粥的复水性质与复水小米粥质构特性的影响。结果表明,速食小米粥的吸水性指数与水溶性指数与复水后小米粥的弹性、胶粘性与咀嚼性能用多元二次模型进行拟合。其中,料液比对复水小米粥的弹性没有显著影响,煮粥时间对复水小米粥的质构特性有显著影响,冻干温度对水溶性指数与胶粘性有显著影响。速食小米粥的复水时间与煮粥时水分质量分数呈负相关关系。

小米粥加工过程中营养成分及抗氧化活性的变化

小米加工成米粥后供人食用,为研究其在加工过程中生理活性物质的变化规律,对小米经高压蒸煮、冷冻干燥、复水加工制成速食小米粥过程中氨基酸、酚酸、黄酮含量及提取物的抗氧化能力变化进行研究。结果表明,总氨基酸与必需氨基酸含量在加工过程中无显著性差异,小米中结合态酚酸高压蒸煮后降低27.87%,对小米中自由态黄酮经高压蒸煮后降低29.57%。冷冻干燥和复水对酚酸与黄酮含量影响不显著。复水后小米粥中的香草酸含量与小米相比增长73.94%。复水小米粥中自由态与结合态酚酸提取物清除DPPH自由基能力分别比小米中降低55.83%和88.39%;高压蒸煮后自由态与结合态酚酸提取物三价铁还原能力显著下降,分别下降30.08%和39.74%;冷冻干燥和复水对酚酸提取物三价铁还原能力无显著影响。

Novel DNA vaccine based on hepatitis B virus core gene induces specific immune responses in Balb/c mice

AIM： To investigate the immunogenidty of a novel DNA vacoine, pSW3891/HBc, based on HBV core gene in Balb/c mice. METHODS： A novel DNA vaccine, pSW3891/HBc, encoding HBV core gene was constructed using a vector plasmid pSW3891. Balb/c mice were immunized with either pSW3891/HBc or empty vector DNA via gene gun. IgG anti-HBc responses in mouse sera were demonstrated by ELISA. Specific cytotoxicity of cytotoxic T lymphocytes （CTLs） of mice was quantitatively measured by lactate dehydrogenase release assay. RESULTS： HBcAg was expressed effectively in 293T cell line transiently transfected with pSW3891/HBc. Strong IgG anti-HBc responses were elicited in mice immunized with pSW3891/HBc. The end-point titers of anti-HBc reached the highest 1：97 200, 4 wk after the third immunization. The specific CTL killing with the highest specific lysis reached 73.25% at effector：target ratio of 20：1 in mice that received pSW3891/HBc DNA vaccine. CONCLUSION： pSW3891/HBc vaccination elicits specific anti-HBc response and induces HBc-specific CTL response in immunized Balb/c mice.

Changes of Extreme Precipitation and its Associated Mechanisms in Northwest China

Characterized by scarce water resources and fragile ecosystems,Northwest China(NWC)has experienced a climate shift from warm-dry to warm-wet conditions since the 1980s that has garnered extensive concern in recent years.In this study,the variability in extreme precipitation(EP)during 1961-2016 in different climate zones of NWC and the possible mechanisms for this variation are investigated.The results show that the EP trends significantly increased in most of the westerly zone(WZ)and plateau zone(PZ),while the EP trends did not significantly decrease in the monsoon zone(MZ).The start dates of extreme precipitation(SDEP)and end dates of extreme precipitation(EDEP)advanced and were postponed,respectively,in the WZ and PZ,while the opposite occurred in the MZ.Summer atmospheric circulation,water vapor transport,and atmospheric instability over NWC varied greatly with the interdecadal shift in EP before and after 1986.During 1986-2016,upper-level divergence and lower-level convergence occurred in the MZ and PZ,which strengthened ascending flow.In addition,the summer water vapor and atmospheric instability increased in the WZ and PZ.These characteristics created favorable conditions for increased occurrences of EP in the WZ and PZ in summer.Conversely,the upper-level convergence and lower-level divergence in the MZ strengthened descending flow.Decreases in summer water vapor and atmospheric instability occurred in the MZ after 1986.Hence,the environmental conditions in the MZ may have prevented the occurrence and development of EP in summer during 1986-2016.

A Study on Service-Oriented Smart Medical Systems Combined with Key Algorithms in the IoT Environment

A smart medical service system architecture is proposed in this paper to increase medical resource utilization and improve the efficiency of the medical diagnosis process for complex business scenarios in the Medical Internet of Things(MIoT)environment.The resource representation model theory,multi-terminal aggregation algorithm,and the resource discovery algorithm based on latent factor model are also studied.A smart medical service system within the IoT environment is then developed,based on the open source project.Experimental results using real-world datasets illustrate that the proposed smart medical service system architecture can promote the intelligent and efficient management of medical resources to an extent,and assists in the develop towards digitization,intelligence,and precision in the field of medicine.

看电视时间与婴幼儿语言、情绪社会性发展的关系——一项追踪研究

采用追踪设计,利用家庭基本情况调查表调查婴幼儿14～25个月的电视接触时长,利用《汉语沟通发展量表》和《婴幼儿社会-情绪性量表》评估婴幼儿14～25个月语言发展及情绪社会性发展,由此考察看电视时间与婴幼儿语言以及情绪社会性发展的关系,结果发现:(1)在看电视时间与儿童语言发展方面,婴幼儿14个月时,不看电视和看电视30分钟的婴幼儿比看电视超过60分钟的婴幼儿在短语理解上的表现相对更好;每天看电视30分钟的婴幼儿比不看电视和看电视超过60分钟的婴幼儿在动作和手势方面的表现相对更好。在婴幼儿25个月时,没有发现看电视时间长短与此年龄阶段语言发展的相关;14个月婴幼儿看电视时间与其25个月语言发展也没有关系。(2)在看电视时间与情绪社会性发展方面,在婴幼儿14个月时,每天不看电视和看电视30分钟的婴幼儿比看电视15分钟以内的婴幼儿在能力域和掌握动机上表现更好,并且这两组分别在能力域和掌握动机上比看电视超过60分钟的婴幼儿表现更好。在婴幼儿25个月时,不看电视的婴幼儿比看30分钟以内和看电视超过60分钟的婴幼儿在注意力方面表现更好;看电视不超过60分钟的婴幼儿比每天看电视超过60分钟的婴幼儿在亲社会同伴关系中拥有更好的表现。看电视时间在跨年龄段的比较结果显示,每天不看电视的婴幼儿有更多的同伴攻击行为,但不看电视的婴幼儿比看电视15分钟以内以及看电视超过60分钟的婴幼儿注意力表现更好;看电视在15分钟以内的婴幼儿拥有最多的内隐行为问题和焦虑行为;看电视30分钟的婴幼儿比看电视15分钟以内和超过60分钟的婴幼儿在能力域和注意力方面表现更好,且该组婴幼儿比其他组的婴幼儿拥有更好的移情能力。婴幼儿看电视时间对其语言和情绪社会性发展的影响有利有弊,需要家长高度重视,采用合理的方式积极引导婴幼儿养成良好的看电视习惯,从而促进其语言和情绪社会性等方面的健康发展。

Identification of enzymes responsible for the reduction of geraniol to citronellol

The reduction of geraniol to citronellol is the first step for the synthesis of natural phytol in the production of tocopherols and natural vitamin K.Baker's yeast was used in the bioreduction described above as a whole-cell biocatalyst.However,the enzyme responsible for the reduction of geraniol to citronellol is not yet known.Four old yellow enzyme(OYE)genes were cloned from yeast and plants,and expressed in Escherichia coli for a high level of recombinant proteins.The recombinant protein displayed a catalytic activity of converting geraniol to citronellol as a sole product verified by GC-MS analyses.The recombinant OYE2 intact cells were found to show 3.7 and 1.9-fold higher activity than that of yeast cells and the recombinant crude extracts,respectively.Compared to the recombinant fusion enzyme,the entrokinase-cleaved enzyme displayed nearly identical activity for geraniol reduction.To our knowledge,this is the first enzyme identified to catalyze the formation of citronellol from geraniol by reducing the allylic alcohol double bond,which is normally known as inactivating group for the old yellow enzymes.