Temperature Trends and Accumulation of Chill Hours, Chill Units, and Chill Portions in South Carolina

There is considerable concern about the potential impact of climate change on agriculture, such as the accumulation of chilling hours needed to break the dormancy of many perennial plants, like fruit trees. Therefore, this study aimed to determine if there had been a significant change in air temperatures and chill hours, chill units, and chill portion accumulation in South Carolina over the last two decades. Two decades of daily maximum (Tmax) and minimum (Tmin) air temperature records were obtained from weather stations in thirty-one counties in South Carolina. Hourly temperature data, reconstructed from the daily data, were used to calculate the daily and annual chill hours, chill units, and chill portions accumulation using four different chill models for each location and year. The chill models included the T(t) °C model, the 0°C °C model, the Utah model, and the Dynamic model. For each county, regression analyses were conducted to evaluate the historical trends. Despite year-to-year variability, the tendency was a statistically significant (α = 0.05) increase in air temperature, averaging 0.089°C per year for 20 out of 31 counties in South Carolina. The other 11 counties had no significant change in temperature. The average temperature increase in the 31 counties was 0.072°C per year. The temperature increase resulted in a decrease in annual chill accumulation during the fall to spring, averaging 17.7 chill hours, 8.6 chill hours, 17.0 chill units, and 0.40 chill portions per year calculated with the T(t) °C, 0°C °C, Utah, and Dynamic models, respectively. However, whether this decrease in chill values was statistically significant or not depended on the chill model used. This study did not investigate the cause of the observed historical trends in temperature and chill accumulation. Still, if the trends continue, they could significantly impact the future of the temperate fruit tree industry in the state.

Quantification of Above-Ground Biomass and Carbon Sequestration Potential of Roadside Trees in the Plateau Department of Benin Republic

Roadside trees are effective natural solutions for mitigating climate change. Despite the usefulness of trees to carbon sequestration, there is a dearth of information on the estimation of biomass and carbon stock for roadside trees in the study area. This study aimed to estimate the carbon stock and carbon dioxide equivalent of roadside trees. A complete enumeration of trees was carried out in Kétou, Pobè and Sakété within the communes of the Plateau Department, Bénin Republic. Total height and diameter at breast height were measured from trees along the roads while individual wood density value was obtained from wood density database. The allometric method of biomass estimation was adopted for the research. The results showed that the total estimations for above-ground biomass, carbon stock and carbon equivalent from all the enumerated roadside trees were 154.53 mt, 72.63 mt and 266.55 mt, respectively. The results imply that the roadside trees contain a substantial amount of carbon stock that can contribute to climate change mitigation through carbon sequestration.

昭通褐煤催化热溶解聚及其可溶物组成和结构特征

温和热溶是从褐煤获取可溶有机质的有效途径,然而传统热溶过程可溶物收率较低。通过共沉淀法制备了一系列Al_(2)O_(3)负载金属催化剂,考察了昭通褐煤在异丙醇中的热溶和催化热溶行为。采用XRD、H_(2)-TPR、TEM和XPS研究了催化剂的物理化学特征,利用GC/MS、FTIR和MALDI-TOF-MS分析了热溶和催化热溶可溶物的组成和结构特征。结果表明,NiCu/Al_(2)O_(3)对昭通褐煤的催化热溶活性优于其他催化剂,该催化剂中活性组分以NiCu合金的形式存在,且Ni与Cu之间存在相互作用。热溶与催化热溶可溶物收率均随温度升高呈先上升后下降的趋势,320℃可溶物收率最高,分别为27.69%和50.54%。催化剂的引入可提高昭通褐煤可溶物中油、沥青烯(AS)和前沥青烯(PAS)收率,其中油和PAS的收率提升相较AS更明显。酚类化合物是非催化热溶衍生油的主要族组分,相对含量达到64.44%,而催化热溶衍生油主要由芳烃、酚类、醇类和酮类化合物组成,说明催化剂促进了可溶有机质碎片中共价键的断裂和酚类化合物加氢。与非催化热溶得到的AS和PAS相比,催化热溶得到的AS和PAS分子量分布范围窄,且FTIR谱图中羟基和醚键对应的吸收峰变弱或消失,说明催化热溶促进了C—O键加氢裂解。催化热溶可在相对温和的条件下从煤中直接高收率获取可溶有机质,研究结果为从褐煤直接获取化学品技术的开发提供参考。

药用植物地下部生长发育研究进展

植物的地下部不仅是植物从外界获取营养物质的重要组成部分,还是植物体内多种有机酸、氨基酸和激素合成与转化的重要场所。以地下部为主要药用部位的药用植物,其地下部生长状况直接影响药材的产量与品质,间接地影响到种植农户的收入、疾病的临床用药治疗效果、民众的健康水平等。近年来随着药用植物地下部研究的深入,与其生长发育有关的影响因子日益受到重视与关注。因此,围绕环境因子、激素对植物地下部的影响以及地下部生长发育的分子机制等内容进行综述,以供药用植物地下部的进一步研究作参考。

基于数据库的玻璃纤维增强复合材料箍筋弯拉强度计算方法

玻璃纤维增强复合材料箍筋弯拉强度试验主要研究弯折半径与直径之比对弯拉强度的影响,直线段抗拉强度对弯拉强度的影响研究较少。本文基于ACI 440.3R-12中B.5试验方法,开展3组(9个弯拉试件)不同直线段抗拉强度的玻璃纤维增强复合材料箍筋弯拉强度试验研究。3组试件直线段抗拉强度分别为530(A组)、850(B组)和1100 MPa(C组),弯折半径与箍筋直径之比均为3。试验结果表明:所有试件均发生玻璃纤维增强复合材料箍筋弯折段被拉断的破坏模式;A、B、C组试件弯拉强度分别为325、445和530 MPa。本文系统收集了国内外已有93个弯拉试件,并结合本文9个弯拉试件建立了玻璃纤维增强复合材料箍筋弯拉强度试验数据库。基于数据库统计分析,提出了保证率不小于95%的玻璃纤维增强复合材料箍筋弯拉强度计算方法。

Differential roles of seed and sprout regeneration in forest diversity and productivity after disturbance

Natural regeneration after disturbances is a key phase of forest development,which determines the trajectory of successional changes in tree species composition and diversity.Regenerating trees can originate from either seeds or sprouts produced by disturbed trees with sprouting ability.Although both regeneration strategies often develop and co-occur after a disturbance,they tend to affect forest development differently due to significant functional differences.However,the origin of tree regeneration is rarely distinguished in post-disturbance forest surveys and ecological studies,and the differential roles of seed and sprout regeneration in forest productivity and diversity remain poorly understood.To address these research gaps,we explored the role of sprout and seed regeneration in the formation of woody species diversity and above-ground biomass(AGB)productivity in early-stage forest development.Data were collected in two experimental forest stands in the Czech Republic,where trees were cut with varying intensities with the density of residual(uncut)trees ranging from 0 to 275 trees per hectare.All trees were mapped and their sizes were measured before cutting and then,either as a stump with sprouts or a residual tree,remeasured 11 years later.In addition,all tree saplings were mapped and measured 11 years after logging,and their origin(sprout or seed)was identified.To assess abundances and productivity,we estimated AGB of all2,685 sprouting stumps of 19 woody species and 504 generative(i.e.,seed origin)individuals of 16 woody species,using allometric equations.Mixed-effects models were used to analyze the effects of each regeneration strategy on woody species diversity and the total AGB under varying densities of residual trees.Nonmetric multidimensional scaling was used to evaluate the effect of regeneration strategies on species composition.AGB and diversity of sprouts were significantly higher than those of seed regeneration.Sprouts formed on average97.1%of the total regeneration AGB in H ady and 98.6%in Sobe s ice.The average species richness of sprouts was4.7 in H ady and 2.2 in Sob e sice,while the species richness of seed regeneration averaged 2.1 and 1.1 in H ady and Sob e sice,respectively.Increasing density of residual trees reduced AGB and diversity of both sprouts and seed regeneration,but seed regeneration was affected to a greater extent.Residual trees had an especially strong inhibitory effect on the establishment of seed regeneration.Consequently,seed-originated saplings were nearly absent in plots with high residual tree density,and abundant sprouts accounted for most of the AGB and diversity.However,unlike sprouts whose species composition resembled that of the original stand,seed regeneration brought in new species,enriching the stand?s overall species pool and beta diversity.Our results demonstrated differential roles of sprout and seed regeneration in the early stage of forest succession.Sprout regeneration was the main source of woody AGB productivity as well as species diversity,and its importance increased with the increasing density of standing mature trees.The results indicate the crucial yet previously underestimated role of sprout regeneration in post-disturbance forest dynamics.They suggest that the presence of residual mature trees,whether retained after partial cutting or undisturbed,can substantially suppress seed regeneration while the role of sprout regeneration in early succession becomes more distinctly evident.

一种变工况下海流发电机叶片附着物检测方法

针对流速变化使得变工况下海流发电机叶片附着物故障特征模糊、鉴别性差的问题,提出一种基于自适应频率正比采样(APFS)的叶片附着物检测方法。首先,采集不同工况下海流发电机电流信号,通过希尔伯特变换提取出定子电流信号的瞬时频率;然后,利用瞬时频率与采样频率比值变步长采样瞬时频率序列,将非稳定瞬时转动频率转变为稳定值;最后,利用排列熵设置采样迭代停止阈值,将重采样后的瞬时频率序列作为故障特征划分为样本矩阵,建立主成分分析检测模型以实现附着物检测。基于0.23 kW海流发电样机的实验平台被搭建用于验证所提方法的有效性,实验结果表明,所提算法在对抗流速变化下引起的海流发电机变工况问题中,误报率低至0.25%,具备较高检测精度和鲁棒性。

基于可穿戴惯性传感技术的人体步态阶段识别

为了实现基于可穿戴惯性传感技术的人体步态阶段识别,开发了基于特征选择的人体步态阶段识别模型、基于时间比例优化的人体步态阶段识别模型和基于机器学习多数据类型、多特征、多分类器的人体步态阶段识别模型,并对比了3种模型的步态阶段识别效果。结果表明:基于特征选择的人体步态阶段识别模型的平均识别准确率为73.66%;基于时间比例优化的人体步态阶段识别模型的平均识别准确率为90.96%;利用脚背处俯仰角数据和加速度数据训练得到的基于机器学习的人体步态阶段识别模型的平均识别准确率分别为97.04%、86.80%;针对不同的步态阶段和使用场景,可差异化选择不同的识别方法以获得理想的识别效果;综合采用时间比例优化算法和机器学习方法可以获得较高的综合识别准确率。该研究可为进一步开展基于可穿戴式传感器的人体行为相关研究提供参考。

三部开窍利咽针刺辅助吞咽功能训练治疗急性缺血性脑卒中后吞咽功能障碍的临床研究

目的:分析三部开窍利咽针刺辅助吞咽功能训练治疗急性缺血性脑卒中(AIS)后吞咽功能障碍的临床疗效。方法:选定山东省滕州市中心人民医院2020年1月—2022年1月住院的112例AIS后吞咽功能障碍患者展开回顾性研究,根据治疗方案的不同将其分为两组,每组56例,对照组给予吞咽功能训练,观察组在对照组基础上给予三部开窍利咽针刺治疗,比较两组临床疗效、吞咽功能评定量表(SSA)评分、吞咽X线荧光透视检查(VFSS)评分、洼田氏饮水试验、不良事件总发生率、吞咽障碍特异性生活质量量表(SWAL-QOL)评分和改良的Barthel量表(MBI)评分。结果:观察组临床总有效率为96.43%(54/56),高于对照组总有效率的75%(42/56),差异具有统计学意义(P<0.01)。观察组治疗后SSA评分低于对照组,差异具有统计学意义(P<0.01),观察组治疗后VFSS评分高于对照组,差异具有统计学意义(P<0.01)。观察组治疗后洼田氏饮水试验1级率23.21%(13/56)、2级率41.08%(23/56)均高于对照组7.14%(4/56)、28.57%(16/56),差异具有统计学意义(P<0.05)。观察组不良事件总发生率1.79%(1/56)低于对照组的14.29%(8/56),差异具有统计学意义(P<0.05)。观察组治疗后SWAL-QOL评分、MBI评分均高于对照组,差异具有统计学意义(P<0.01)。结论:三部开窍利咽针刺辅助吞咽功能训练可有效减轻AIS后吞咽功能障碍患者吞咽困难、饮水呛咳等症状,降低吸入性肺炎等不良事件发生率,改善生活质量及自理能力,临床疗效显著。

低阶煤催化加氢裂解可溶物的结构分析

采用水热合成法制备了CuFeO_(2)催化剂,并将其应用于低阶煤的催化加氢裂解,将所得反应混合物利用石油醚进行萃取。采用气相色谱质谱联用仪(GC/MS)分析可溶物的组成和结构特征。结果表明:水热合成法制备的CuFeO_(2)催化剂是纳米级的CuFeO_(2)颗粒;GC/MS检测到的化合物可以划分为4个族组分,分别为脂肪烃、芳烃、含氧化合物和含氮化合物,其中芳烃的相对含量最高。研究结果对于低阶煤在温和条件下的清洁高效转化具有一定的理论指导作用。

低阶煤的催化乙醇解及衍生可溶物的结构分析

对陕北低阶煤的催化乙醇解进行了研究,通过对石油醚萃取可溶物的GC/MS和FTIRS分析,确定可溶物的种类以及各组分含量。结果表明:石油醚萃取可溶物中主要有醇类、酯类、醚类、菲类、苯酚类等化合物,其他芳香族化合物和含氮化合物含量较少。经过催化乙醇解后,低阶煤中的多种>C—O—桥键断裂,生成高附加值的小分子醇和酯类。研究结果对陕北低阶煤的清洁高值利用有重要意义,也为低阶煤的催化乙醇解的发展提供理论支持。

论专利主题名称限定作用的判断规则

主题名称作为权利要求前序部分的重要组成,其限定作用的判断,关系专利权保护范围的界定。司法解释虽明确前序部分具有限定作用,但前序部分中的主题名称是否单独具有限定作用仍存在争议。司法判断规则经历了从主题名称“是否构成技术特征”到“是否产生实质性影响”的转变,规则虽不断调整细化,但仍然存在适用性、合理性的问题,影响权利要求的公示效应。应当立足于主题名称限定作用的特殊定位,完善判断规则:一是坚持折衷原则的指导,明确主题名称具有限定专利保护范围的作用;二是细化司法裁判规则,明确主题名称限定作用判断的原则和例外;三是优化授权审查规则,规范主题名称的撰写。

Laparoscopic partial resection for hemangioma in the third portion of the duodenum

Benign duodenal tumors are rare and less commonthan malignant tumors.Furthermore,vascular lesionsof the duodenum,including hemangiomas,are rarecauses of gastrointestinal bleeding.This report describes a case with bleeding hemangiomas in the thirdportion of the duodenum and jejunum and their successful treatment using a laparoscopic approach.Thereis no report of totally laparoscopic resection for tumorin the third portion of duodenum.After performinga laparoscopic Kocher maneuver,the location of theduodenal hemangioma was confirmed by endoscopicand laparoscopic observation.The lesion was excisedusing ultrasonic coagulating shears and the defect inthe duodenal wall was sutured laparoscopically.Thehemangioma of the jejunum was treated extracorporeally through a 3.0 cm umbilical incision.The operatingtime was 241 min and blood loss was negligible.Thepostoperative course was uneventful.For benign duodenal tumors in the third portion,if endoscopic resection is not adapted,this less invasive technique may be a standard treatment.

Co-occurrence Patterns of Above-ground and Below-ground Mite Communities in Farmland of Sanjiang Plain, Northeast China

One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale.

Biomass and dominance of conservative species drive above-ground biomass productivity in a mediterranean-type forest of Chile

Background: Forest productivity has a pivotal role in human well-being. Vegetation quantity, niche complementarity, mass-ratio, and soil resources are alternative/complementary ecological mechanisms driving productivity. One challenge in current forest management depends on identifying and manipulating these mechanisms to enhance productivity. This study assessed the extent to which these mechanisms control aboveground biomass productivity(AGBP) of a Chilean mediterranean-type matorral. AGBP measured as tree aboveground biomass changes over a 7-years period, was estimated for twelve 25 m × 25 m plots across a wide range of matorral compositions and structures. Variables related to canopy structure, species and functional diversity, species and functional dominance, soil texture, soil water and soil nitrogen content were measured as surrogates of the four mechanisms proposed. Linear regression models were used to test the hypotheses. A multimodel inference based on the Akaike’s information criterion was used to select the best models explaining AGBP and for identifying the relative importance of each mechanism.Results: Vegetation quantity(tree density) and mass-ratio(relative biomass of Cryptocarya alba, a conservative species) were the strongest drivers increasing AGBP, while niche complementarity(richness species) and soil resources(sand, %) had a smaller effect either decreasing or increasing AGBP, respectively. This study provides the first assessment of alternative mechanisms driving AGBP in mediterranean forests of Chile. There is strong evidence suggesting that the vegetation quantity and mass-ratio mechanisms are key drivers of AGBP, such as in other tropical and temperate forests. However, in contrast with other studies from mediterranean-type forests, our results show a negative effect of species diversity and a small effect of soil resources on AGBP.Conclusion: AGBP in the Chilean matorral depends mainly on the vegetation quantity and mass-ratio mechanisms.The findings of this study have implications for matorral restoration and management for the production of timber and non-timber products and carbon sequestration.

Estimation of the Above-ground Biomass of Tamarix Species along a Transect at the Tarim River's Middle Reaches

[Objective] The purpose was to research the distribution characteristics of Tamarix species above-ground biomass of Tarim River＇s middle reaches and to find out best-fit linear-regression model of Tamarix species in this area.[Method] By dint of the most common sampling method PCQ,five samples in the middle reaches of Tarim River were collected.The best-fit linear-regression model of Tamarix species of this area was set up,based on the fieldwork and the model of Evangelista and obtained the distribution rules of Tamarix species of Tarim River＇s middle reaches.[Result] The result indicated that this model fitted for the estimation of aboveground biomass of the study area.According to the distribution rules of aboveground biomass,it was clear that underground water was the major element which decided the distribution of aboveground biomass.[Conclusion] The study provided theoretical basis for the calculation of biomass of Tamarix.

Estimating above-ground biomass by fusion of LiDAR and multispectral data in subtropical woody plant communities in topographically complex terrain in North-eastern Australia

We investigated a strategy to improve predicting capacity of plot-scale above-ground biomass （AGB） by fusion of LiDAR and Land- sat5 TM derived biophysical variables for subtropical rainforest and eucalypts dominated forest in topographically complex landscapes in North-eastern Australia. Investigation was carried out in two study areas separately and in combination. From each plot of both study areas, LiDAR derived structural parameters of vegetation and reflectance of all Landsat bands, vegetation indices were employed. The regression analysis was carded out separately for LiDAR and Landsat derived variables indi- vidually and in combination. Strong relationships were found with LiDAR alone for eucalypts dominated forest and combined sites compared to the accuracy of AGB estimates by Landsat data. Fusing LiDAR with Landsat5 TM derived variables increased overall performance for the eucalypt forest and combined sites data by describing extra variation （3% for eucalypt forest and 2% combined sites） of field estimated plot-scale above-ground biomass. In contrast, separate LiDAR and imagery data, andfusion of LiDAR and Landsat data performed poorly across structurally complex closed canopy subtropical minforest. These findings reinforced that obtaining accurate estimates of above ground biomass using remotely sensed data is a function of the complexity of horizontal and vertical structural diversity of vegetation.

Global patterns in above-ground net primary production and precipitation-use efficiency in grasslands

The above-ground net primary production(ANPP) and the precipitation-use efficiency(PUE) regulate the carbon and water cycles in grassland ecosystems, but the relationships among the ANPP, PUE and precipitation are still controversial. We selected 717 grassland sites with ANPP and mean annual precipitation(MAP) data from 40 publications to characterize the relationships ANPP–MAP and PUE–MAP across different grassland types. The MAP and ANPP showed large variations across all grassland types, ranging from 69 to 2335 mm and 4.3 to 1706 g m^(-2), respectively. The global maximum PUE ranged from 0.19 to 1.49 g m^(-2) mm^(-1) with a unimodal pattern. Analysis using the sigmoid function explained the ANPP–MAP relationship best at the global scale. The gradient of the ANPP–MAP graph was small for arid and semi-arid sites(MAP <400 mm). This study improves our understanding of the relationship between ANPP and MAP across dry grassland ecosystems. It provides new perspectives on the prediction and modeling of variations in the ANPP for different grassland types along precipitation gradients.

Estimating canopy closure density and above-ground tree biomass using partial least square methods in Chinese boreal forests

Boreal forests play an important role in global environment systems. Understanding boreal forest ecosystem structure and function requires accurate monitoring and estimating of forest canopy and biomass. We used partial least square regression （PLSR） models to relate forest parameters, i.e. canopy closure density and above ground tree biomass, to Landsat ETM＋ data. The established models were optimized according to the variable importance for projection （VIP） criterion and the bootstrap method, and their performance was compared using several statistical indices. All variables selected by the VIP criterion passed the bootstrap test （p〈0.05）. The simplified models without insignificant variables （VIP 〈1） performed as well as the full model but with less computation time. The relative root mean square error （RMSE%） was 29% for canopy closure density, and 58% for above ground tree biomass. We conclude that PLSR can be an effective method for estimating canopy closure density and above ground biomass.

Adenocarcinoma of the third duodenal portion:Case report and review of literature

We focus on the diagnostic and therapeutic problems of duodenal adenocarcinoma, reporting a case and reviewing the literature. A 65-year old man with adenocarcinoma in the third duodenal portion was successfully treated with a segmental resection of the third part of the duodenum, avoiding a duodeno-cephalo-pancreatectomy. This tumor is very rare and frequently affects the III and IV duodenal portion. A precocious diagnosis and the exact localization of this neoplasia are crucial factors in order to decide the surgical strategy. Given a non-specificity of symptoms, endoscopy with biopsy is the diagnostic gold standard. Duodeno-cephalo-pancreatectomy (DCP) and segmental resection of the duodenum (SRD) are the two surgical options, with overlapping morbidity (27% vs 18%) and post operative mortality (3% vs 1%). The average incidence of postoperative long-term survival is 100%, 73.3% and 31.6% of cases after 1, 3 and 5 years from surgery, respectively. Long-term survival is made worse by two factors: the presence of metastatic lymph nodes and tumor localization in the proximal duodenum. The two surgical options are radical: DCP should be used only for proximal localizations while SRD should be chosen for distal localizations.