模具设计与制造专业班会内容与PTS人生技能课程相融合的研究

模具设计与制造专业学生的班会内容与专业拓展课《PTS人生技能》的内容相融合,先分析模具设计与制造专业的培养目标,阐述拓展课的8个模块,并以“理解和管理情绪模块”为例进行了主题班会的实施过程的介绍。班会内容与PTS人生技能课的融合是一种有益的尝试,班会中应用了课程的“演、思、说、用”4个环节。以学生为中心的理念,经验学习圈理论。让学生在班会中学习和应用人生技能,提升了个人综合素质,为学生的全面发展提供有力支持。

高苯丙氨酸血症家系PAH和PTS基因突变研究

目的 检测湖北省地区26例中国人高苯丙氨酸血症家系基因突变,研究其基因型、表型和遗传学特征。方法 采集2018年3月至2020年12月在武汉儿童医院就诊的26例HPA患儿和父母静脉血样本,并收集其临床资料,提取DNA,应用聚合酶链式反应(PCR)扩增PAH基因和PTS基因编码区及其侧翼序列,并以直接测序法对扩增产物正反测序进行突变分析。同时选取同时段来本院健康体检无明显异常儿童100名为正常对照组,处理方式与患儿相同。结果 患儿中检出PAH基因突变24种,其中c.728G>A(R243Q)最常见,等位基因突变率为15.2%(7/46)。发现一新PTS基因突变IVS3+9A>G。3例BH4缺乏型患儿中检出PTS基因P87S、D96N和A111T突变,其中P87S是最常见致病突变。在正常对照组中,未检出以上患儿中携带的突变,仅检出三种突变Q232Q(c.696A>G)、V245V(c.735G>A)和L385L(c.1155G>C),均为同义突变,不改变编码氨基酸,属于正常DNA多态。结论 PAH基因突变引起患儿PAH缺乏型HPA,而PTS基因突变引起严重型BH4缺乏症。基因检查的结果可为临床诊断和选择合适的治疗方案提供参考,并且可为进一步生育指导提供参考。

高分散PtSn/CeO_(2)催化剂对甲烷完全氧化的促进作用

负载型金属催化剂在甲烷完全氧化中应用十分广泛,金属颗粒的大小是决定催化剂性能的关键因素。对于贵金属催化剂,较高的分散性有利于提高催化活性和降低催化剂成本。针对这一问题,以CeO_(2)作为载体、Sn为助剂,在惰性气氛下实现Pt的分散。对制取的催化剂样品进行表征,以分析PtSn/CeO_(2)处理前后的物理结构和电子性质,并研究了其对甲烷完全氧化反应的催化作用。结果表明,PtSn/CeO_(2)具有较高的催化反应活性,在450℃的反应温度中甲烷的转化率达到了95%。这主要归因于Sn的加入削弱了Pt原子从团簇中的解离能,增强了Pt和CeO_(2)之间的锚定作用。利用DFT计算,从热力学角度解释了造成Pt分散差异的原因,为研究催化剂活性金属的烧结与分散提供了新思路。

Impact of cattle density on the structure and natural regeneration of a turkey oak stand on an agrosilvopastoral farm in central Italy

On an agrosilvopastoral farm in central Italy where Maremmana cattle graze in Turkey oak forests,we evaluated the impact of different livestock densities on stand structure,tree diversity and natural regeneration in four types of grazed areas based on the grazing regime adopted:calf-grazed,high-intensity-grazed,low-intensity-grazed,ungrazed control.For each area,we set up three permanent circular plots(radius of 15 m)to survey the structural and dasometric characteristics of the overstorey,understorey,and regeneration layer.The results showed that grazing negatively affected the complexity of the forest structure and its potential to regenerate and maintain a high level of biodiversity.The differences in stand structure observed between the grazing areas were closely related to livestock density.The most sensitive components of the system were the understorey and the regeneration layers.Contrarily,the current grazing management did not affect the dominant tree structure or its composition.Our findings identified medium-term monitoring and regeneration management as the two significant aspects to consider when assessing sustainable livestock.New forests can be established by excluding graz-ing for about 20–25 years.

Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu

Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand.

Simulation of Haloxylon Ammodendron Stand Basic Diameter Structure Based on Fuzzy Distribution Function

Based on the investigation data of 12 Haloxylon ammodendron plots in the south edge of Gurbantunggut Desert, Fuzzy distribution was introduced into the study of Haloxylon ammodendron base diameter structure fitting according to the consistency between the characteristics of Fuzzy distribution function and the distribution series of cumulative percentage of stand base diameter, and the fitting precision and effect of Fuzzy distribution function were discussed. The root mean square error RMSE and determination coefficient R2 values showed that Fuzzy-Γ1, Fuzzy-Γ2, Fuzzy-Γ3, Fuzzy-Γ4 had good fitting performance, among which Fuzzy-Γ1 had relatively high fitting precision, and its parameters were closely related to stand age and density, Fuzzy-Γ2 distribution function was the second, and Fuzzy-Γ4 distribution function had the worst fitting effect. By introducing a parameter c from the similarity of four distribution function formulas, a generalized Fuzzy distribution function Fuzzy-Γ5 is obtained. This function shows the highest fitting accuracy. Most of the values of parameter c are near 1 or 2, which shows that the diameter distribution is mainly approximate to Fuzzy-Γ1 and Fuzzy-Γ2.

Study on Free-Standing Riser Under Different Working Conditions Based on 3D Co-Rotational Beam Element

When the free standing riser(FSR)is in service in the ocean,its mechanical properties are affected by various factors,including complex ocean current forces,buoyancy of the buoyancy can,and torque caused by the deflection of the upper floating body.These loads have a great influence on the deformation and internal force of the FSR.The static performance of FSR is investigated in this research under various working conditions.The finite element model of FSR is established based on the co-rotational method.The arc length approach is used to solve the model.The load is exerted in increments.The current load on the riser changes with the configuration of the riser.The accuracy of the numerical method is verified by Abaqus software.The calculation time is also compared.Then,the effects of uniform current,actual current and floating body yaw motion on FSR are studied by parameter analysis.Additionally,the influence of the FSR on the ocean current after the failure of part of the buoyancy can chamber is analyzed.The results show that the numerical model based on the co-rotational method can effectively simulate the large rotation and torsion behavior of FSR.This method has high computational efficiency and precision,and this method can quickly improve the efficiency of numerical calculation of static analysis of deep-water riser.The proposed technology may serve as an alternative to the existing proprietary commercial software,which uses a complex graphical user interface.

The effects of data aggregation on long-term projections of forest stands development

Forest management planning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient decision-making.Employing the area-based(ABA)approach,these inventories estimate forest characteristics for grid cell areas(pixels),which are then usually summarized at the stand level.Using the ALS-based high-resolution Norwegian Forest Resource Maps(16 m×16 m pixel resolution)alongside with stand-level growth and yield models,this study explores the impact of three levels of pixel aggregation(standlevel,stand-level with species strata,and pixel-level)on projected stand development.The results indicate significant differences in the projected outputs based on the aggregation level.Notably,the most substantial difference in estimated volume occurred between stand-level and pixel-level aggregation,ranging from-301 to+253 m^(3)·ha^(-1)for single stands.The differences were,on average,higher for broadleaves than for spruce and pine dominated stands,and for mixed stands and stands with higher variability than for pure and homogenous stands.In conclusion,this research underscores the critical role of input data resolution in forest planning and management,emphasizing the need for improved data collection practices to ensure sustainable forest management.

Effects of Standing Time during Pretreatment on the Nitrite Concentration Detected by Spectrophotometric Method

Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a great influence on the concentration of nitrite tested by spectrophotometric method. In this context, three kinds of food samples are prepared, including canned mustard, canned fish and home-made pickled water. A series of standing times are placed during the sample pretreatments and the corresponding nitrite contents in these samples are detected by spectrophotometric method based on N-ethylenediamine dihydrochloride. This study aims to find out a reasonable standing time during the pretreatment of food sample, providing influence factor for precise detection of nitrite.

Existence and Stability of Standing Waves for the Nonlinear Schrödinger Equation with Combined Nonlinearities and a Partial Harmonic Potential

In this paper, we study the existence of standing waves for the nonlinear Schrödinger equation with combined power-type nonlinearities and a partial harmonic potential. In the L2-supercritical case, we obtain the existence and stability of standing waves. Our results are complements to the results of Carles and Il’yasov’s artical, where orbital stability of standing waves have been studied for the 2D Schrödinger equation with combined nonlinearities and harmonic potential.

Runoff Characteristics of Different Stands in Dongjiang Lake Reservoir Area

Different forest stands in the Dongjiang Lake Reservoir area of Zixing were selected as the research objects to study the characteristics of runoff generation in different forest stands.The results showed that there was no significant difference in annual runoff among M3,M1,and M5,and no significant difference between each forest stand and the control.The order was M3(22.75 mm)>M1(21.77 mm)>M5(20.14 mm).Forest vegetation generates less runoff through vegetation restoration compared to the control,indicating that forest vegetation reconstruction and restoration are beneficial for soil and water conservation.

改进的可见光通信系统PTS峰均比抑制方法

针对非对称剪切正交频分复用(asymmetric-clipped orthogonal frequency division multiplexing,ACO-OFDM)可见光通信(visible light communication,VLC)系统中信号的高峰均功率比(peak-to-average power ratio,PAPR)问题,采用部分传输序列(partial transmit sequence,PTS)方法,并结合二进制离散粒子群优化(discrete particle swarm optimization,DPSO)算法,提出一种改进的PTS峰均比抑制方法——DPSO-PTS方法。利用DPSO算法对加权的相位因子进行优化处理,选择最佳的相位因子组合来有效控制PAPR的范围,并对乘加权信息的子块进行求和,从而选择出最小PAPR对应的一组信号进行传输。仿真结果表明,在互补累计分布函数(complementary cumulative distribution function,CCDF)为10-4时,DPSO-PTS方法的系统PAPR降低了约4 dB,且相较于传统PTS方法,系统的复杂度和误码率(bit error rate,BER)性能也得到有效的改善。

Fabrication of Free Standing Nanocellulose Film via Spray Coating and its Biomedical Application: A Review

Spraying nanocellulose onto films provides a quick and scalable way to create free-standing films with exceptional consistency and customizable thickness. This method increases the application of nanocellulose films in various industries and satisfies the requirements of large-scale production. In the field of biomedicine, spray-coated free-standing nanocellulose films hold great promise for applications such as drug delivery, tissue engineering, wound healing, device coatings, and biosensing. They are excellent nanomaterials for a variety of biomedical applications due to their special qualities, including biocompatibility, high mechanical strength, porous structure, large surface area, and adaptability. This paper reviewed the detailed exposure of the spray coating process of nanocellulose suspension onto free- standing films and its biomedical applications.

基于分治优化相位因子序列降低PAPR的PTS算法

针对传统部分传输序列(Partial Transmit Sequence,PTS)算法在改善正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均功率比(Peak to Average Power Ratio,PAPR)时存在较高计算复杂度问题,文章提出了一种改进PTS算法。该算法利用分治思想对候选相位因子序列进行分组,降低其序列维度;结合相位加权序列的特点,进一步降低需遍历的候选序列个数,从而降低了计算复杂度。与传统的PTS算法对比,所提出的改进算法在改善PAPR性能的同时,较大地降低了计算复杂度。

PtS_(2)的表面相工程:单晶PtS_(2)-非晶PtS_(x)-单晶Pt

本文利用原子级扫描透射电子显微术(scanning transmission electron microscopy,STEM)研究了PtS_(2)在连续Ar等离子体作用下其表面S原子不断缺失并导致相转变的过程。实验发现随着S原子占比的减小,层状1T相PtS_(2)以逐层非晶化的方式转变为无定形非晶相PtS_(x)(x<2),并且基于径向分布函数(radial distribution function,RDF)分析定量提取了最邻近Pt-Pt、Pt-S、S-S原子对的分布概率。随着S原子占比的继续减小,表面非晶相PtSx最终转变为单晶Pt,结合电子能量损失谱(electron energy loss spectroscopy,EELS)与STEM原子序数衬度图像分析表明,Pt原子以(111)面心立方密堆的方式堆垛,形成少层甚至单层Pt晶畴。

Eff ects of stand condition and root density on fi ne-root dynamics across root functional groups in a subtropical montane forest

Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-based fi ne root dynamics of trees and their responses to forest stand properties remain unclear.Here,we studied the dynamics of AFRs and TFRs and their responses to stand conditions and root density in a subtropical montane mixed forest based on a 2-a root window experiment.Mean(±SE)annual production,mortality,and turnover rate of AFRs were 7.87±0.17 m m^(−2)a^(−1),8.13±0.20 m m^(−2)a^(−1)and 2.96±0.24 a^(−1),respectively,compared with 7.09±0.17 m m^(−2)a^(−1),4.59±0.17 m m^(−2)a^(−1),and 2.01±0.22 a^(−1),respectively,for TFRs.The production and mortality of fi ne roots were signifi cantly higher in high root-density sites than in low-root density sites,whereas the turnover of fi ne roots was faster in the low root-density sites.Furthermore,root density had a larger positive eff ect than other environmental factors on TFR production but had no obvious impact on AFR production.Tree species diversity had an apparent positive eff ect on AFR production and was the crucial driver of AFR production,probably due to a complementary eff ect,but had no evident impact on TFR.Both tree density and tree species diversity were positively correlated with the mortality of AFRs and negatively related to the turnover of TFRs,suggesting that higher root density caused stronger competition for rooting space and that plants tend to reduce maintenance costs by decreasing TFR turnover.These fi ndings illustrated the importance of root functional groups in understanding root dynamics and their responses to changes in environmental conditions.

Stand-along OLIF植入3D打印解剖型融合器治疗退行性腰椎管狭窄症32例临床分析

目的分析无内固定单纯斜外侧入路椎间融合术(Stand-along OLIF)植入自制3D打印解剖型融合器(3D anatomical type Cage)治疗退变性腰椎管狭窄症(Degenerative lumber spinal stenosis,DLSS)的临床疗效.方法32例退变性腰椎管狭窄症患者均行Stand-along OLIF手术,并采用视觉评分表(VAS)、Oswestry功能障碍指数(oswestry disability index,ODI)、SF-36生活质量量化表评价临床疗效;术前、术后1周、术后3个月、术后6个月、术后12个月及末次随访对手术节段的前缘椎间隙高度(DH)、后缘椎间隙高度(VH)、椎间孔高度(FH)及宽度(FW)、椎管前后矢状径(APD)、椎管横截面积(CSA)等参数进行影像学对比.结果32例患者术后1周至末次随访VAS评分和ODI指数均显著降低,SF-36显著增高(P<0.05);术后1周至末次随访DH、VH、FH、FW、APD及CSA均显著提高(P<0.05).结论Stand-alone OLIF植入3D打印解剖型融合器治疗DLSS具有创伤小、术后康复快、有效改善患者临床症状的优势.

Changes in the growth of Scots pine(Pinus sylvestris L.)stands in an urban environment in European Russia since 1862

A century and a half ago,in the European part of Russia(Moscow),forest scientists established the first long-term observations of forests,many of which are under observation to the present day.In the twentieth century,climate changes and,due to industrial development,forest areas were under air pollution.Based on observations from 157 sites,this study shows that the growth and density of Scots pine(Pinus sylvestris L.)have decreased by the end of the twentieth century.The environment has changed,and the growth and development of plantations has slowed.Pine yields(-34%stand volume)and their life expectancy(on average 50 years)have decreased.These changes are critical for forestry and for the management of forests in urban centers.Due to the decline in growth,ecosystem functions by urban forests has decreased.In order to increase the sustainability of urban forests and the provision of ecosystem services,it is preferable to create multi-species stands with a complex structure.

The impact of height-adjustable desks and classroom prompts on classroom sitting time,social,and motivational factors among adolescents

Purpose:This quasi-experimental study examined the impact of height-adjustable desks in combination with prompts to break up prolonged sitting time during class time and identified social and motivational factors associated with breaking up sitting time among adolescents.Teachers’perceptions of strategies were also examined.Methods:Over 17 weeks,1 classroom in a government secondary school in Melbourne,Australia,was equipped with 27 height-adjustable desks and prompts(posters and desk stickers)to break up classroom sitting time.Teachers received professional development in the use of the desks and prompts.One group of adolescents(n=55)had 2-5 lessons/week using the height-adjustable desks in an intervention classroom,and a comparison group matched by year level and subject(n=50)was taught in traditional“seated”classrooms.Adolescents wore an activPAL monitor at baseline(T0),4 weeks(T1),and 17 weeks(T2)and completed a survey at T0 and T2.Six teachers participated in interviews at T2.Effect sizes were calculated(d).Results:Linear mixed models found that,compared to the traditional“seated”classrooms,the adolescents in the intervention classroom had significantly lower sitting time(T1:-9.7 min/lesson,d=-0.96;T2:-6.7 min/lesson,d=-0.70)and time spent in sitting bouts>15 min(T2:-11.2 min/lesson,d=-0.62),and had significantly higher standing time(T1:7.3 min/lesson,d=0.84;T2:5.8 min/lesson,d=0.91),number of breaks from sitting(T1:1.3 breaks/lesson,d=0.49;T2:1.8 breaks/lesson,d=0.67),and stepping time(T1:2.5 min/lesson,d=0.66).Intervention classroom adolescents reported greater habit strength(d=0.58),self-efficacy for breaking up sitting time(d=0.75),and indicated that having a teacher/classmate remind them to stand as helpful(d=0.50).Conclusion:This intervention shows promise for targeting sitting behaviors in the classroom and indicates that incorporating social and motivational strategies may further enhance outcomes.

Helical streamers guided by surface electromagnetic standing waves

The streamer that is driven by the specific pulse DC discharge parameters can stably form a three-dimensional helical plasma channel in a long dielectric tube in the low-temperature plasma experiment,in cases when there were neither external background magnetic field or other factors that destroyed the poloidal symmetry of the tube.The formation mechanism and chirality of helical streamers are discussed according to the surface electromagnetic standing wave theory.The shape of the helical streamers and the characteristics of helical branches are quantitatively analyzed to further expand the application of plasma and streamer theory in the helix problem and chiral catalytic synthesis.