Prediction of Sugar‐Snap Cookie Diameter Using Sucrose Solvent Retention Capacity,Milling Softness,and Flour Protein Content

During testing of wheats at the early generation developmental stage, often there is not enough seed to mill for bake testing products such as sugar‐snap cookie diameter. This study reports a prediction equation for sugar‐snap cookie diameter that uses sucrose solvent retention capacity (SRC), wheat milling softness, and flour protein content. A total of 507 wheats were milled using three laboratory milling systems (short, medium, and long mill flow). Prediction equations were similar for all three mills. Standard errors of prediction were <2% of the mean estimate of cookie diameter. Additional observations eliminated lactic acid SRC (an indication of glutenin strength), alkaline water retention capacity (a traditional predictor of pastry quality), and flour yield (the main milling quality characteristic) from the prediction model.     

The Use of AERMOD Air Pollution Dispersion Models to Estimate Residential Ambient Concentrations of Elemental Mercury

Source-oriented models are ideally suited to examine the impact of terrain and meteorology and source factors such as stack height when evaluating exposures to air pollutants. A source-oriented, Gaussian plume air pollution dispersion model AERMOD was used to estimate the spatial distribution of elemental mercury (Hg⁰) from a typical coal-fired boiler emitting 0.001 g Hg⁰/s. Hg⁰ was chosen because of its health impact related to potential neurological and reproductive effects which may be especially important for high-risk populations. Results from four simulations using meteorological data from 2004 were compared for flat and hilly terrain from 20- and 55-m stacks at a distance of 1,350 m from the source. Variations within a quadrant were affected primarily by topography. For the 20-m stack, the average annual ambient concentration for individuals living within the northeast (NE) quadrant was significantly lower at 2.5 ng Hg⁰/m³ (P?<?0.001; confidence interval (CI), 2.4?C2.6) in flat terrain versus 3.3 ng Hg⁰/m³ in hilly (P?<?0.001; CI, 1.2?C1.3). NE concentrations of the source showed high spatial variability attributed to topography with 1-h maximums of 4.0 ng Hg⁰/m³ flat versus 7.1 ng Hg⁰/m³ hilly. Not unexpectedly, average annual concentrations were considerably lower for the 55-m stack although topography remained a significant variable with 0.1 ng Hg⁰/m³ in flat terrain (p?<?0.001; CI, 0.11?C0.13) and double that exposure at 0.2 ng Hg⁰/m³ in hilly terrain (p?<?0.001; CI, 0.16?C0.18). Annual average mercury concentrations due to emissions from the 20-m stack were ~20 times higher than ambient concentrations associated with the 55-m stack. A sensitivity analysis was performed for meteorological effects, using meteorological data from years 2001?C2005. Varying the roughness factor had no significant effect on the results. For all simulations, the highest concentrations were located in the NE quadrant. During 2001?C2005, the highest average annual ambient Hg concentration ranged from 6.2 to 7.0 ng Hg⁰/m³ for the 20-m stack and 0.3?C0.5 ng Hg⁰/m³ for the 55-m stack. Thus, this model is robust. These results demonstrate the usefulness of a source-oriented model such as AERMOD for incorporating multiple factors for estimating air pollution exposures for communities near point sources. The importance of considering topography, meteorology, and source characteristics when placing air samplers to measure air quality and when using buffer zones to estimate ambient residential exposures is also illustrated. Residential communities in hilly terrain near industrial point sources may have between two to three times the exposures as those in flat terrain. Exposures will vary depending on the stack height of the point source.     

Einkorn Characterization for Bread and Cookie Production in Relation to Protein Subunit Composition

Twenty-four einkorns were evaluated for agronomic traits in Italy and in Germany in replicated plot trials. After dehulling and milling, the harvested kernels, flour protein content, sedimentation volume, falling number, carotenoid, and dry gluten content were determined. Farinograph profiles were obtained with a farinograph and baking and cookie quality were evaluated with standard microtests. Significant differences in yield potential were observed between the two locations, with a three-fold increase in Germany as compared with Italy. One of the einkorn lines (ID529) had farinograph stability and degree of softening indices better than those of the control bread wheat. All the samples analyzed for breadmaking aptitude showed some degree of stickiness, but it was possible to handle the dough during the different steps of breadmaking. On average, cookies produced with einkorn flour were larger in diameter and thinner than those produced with soft wheat flour. The composition in α-, β- and γ-gliadins and in high molecular weight glutenin subunits was similar in all the lines. In contrast, the pattern exhibited in low molecular weight glutenin subunits correlated strictly with baking quality. In particular, the lines with bands arbitrarily designated a and b showed a high breadmaking potential, while the lines lacking these bands had an ample range of variability but, on average, a much lower baking potential. Our data point to a simple genetic control of the breadmaking aptitude and indicate einkorn not only as a promising source of specialty foods but also as an ideal species for genetic investigations on wheat quality.     

利用鸟类评估生态工法成效之可行性探讨

近年来，国际上风行所谓的“生态工法”（Ecological Engineering Methods)，而台湾自1997年起亦大力倡导，虽然有许多学者提出相关论述，但仍仅停留于技术发展阶段，致于如何共评估生态成效，则仍未触及，由于生态成效所涉猎的范围甚为广泛，如何评估实为一大课题。鸟类是一种对于环境相当敏感的族群，而且比较容易观测，因此许多研究常常以鸟类与环境的关系进行探讨，鸟类在生态上为较高级的消费者，因此当植物发生改变时，鸟类的数量与种类也随之改变，探讨鸟类做为评估生态工法成效可行性，并应用穿越线法（Line transects)探讨中兴大学校园内不同植群对于鸟类栖息的影响，结果发现鸟类于不同植群时，其数量与类别有显著的差异，由观测的结果发现，鸟类的栖息与植群环境的关系密切，且许多文献均指出不同的鸟类其栖息环境均有差异，因此选择适当的指针鸟类，可做为评估生态工法成效之参考。     

Contribution of Wheat Flour Fractions to Peak Hot Paste Viscosity

The quality of many baked products, noodles, gravies, and thickeners is related to the pasting properties of wheat (Triticum aestivum L.) flour, yet different flours vary markedly in their pasting performance. The objective of the present research was to assess the role of the wheat flour fractions, gluten, water solubles, prime and tailing starches, in the contribution to peak hot paste viscosity among three selected wheat cultivars. Straight-grade flours were fractionated and reconstituted. Fractions were examined independently and were deleted in otherwise fully reconstituted flours. Fractions were exchanged between cultivars for reconstituting flours, and fractions were substituted individually into a common starch base. The flours from the cultivars Klasic, McKay, and Madsen differed markedly in their peak hot paste viscosities, and were fractionated and reconstituted with only a small effect on paste viscosity. Results clearly showed that prime starch was the primary determinate of flour paste viscosity, but the other fractions all exerted a significant effect. Tailing starch increased paste viscosity directly due to pasting capacity of starch or indirectly through competition for water. Gluten also increased paste viscosity through competition for water. The water-soluble fraction from different cultivar flours was more variable in effect.     

A Fast Colorimetric Method to Estimate Corn Quality Loss

A fast method to estimate the loss of corn quality for wet milling as a result of excessive thermal treatment during drying is proposed. Proteins that remain soluble after drying were quantitatively extracted with a solution of phosphoric acid and ethanol. The soluble proteins were colorimetrically quantified using Coomasie Brillant Blue G dye and measuring at 595 nm. A decrease in absorbance values indicates a reduction in commercial quality of the corn. The application time of the proposed technique is ≈30 min.     

Impact of Fat on Dough and Cookie Properties of Sugar‐Snap Cookies

Fat, one of the three major ingredients of sugar‐snap cookies, affects dough properties, changes in dough dimensions during baking, and in the end, the properties of the baked product. We studied the effect of reducing fat levels (from 15.8 to 8.7% on a dough basis) on dough and cookie properties and related it to the SDS extractable protein (SDSEP) levels. Reducing fat levels increased dough elasticity (from 0.19 to 0.60 MPa) and dough intrinsic hardness (from 8.6 to 27.5 N·cm³/g). Because no differences in dough SDSEP levels were noticed when fat levels were reduced, the increased dough elasticity and hardness were related to a more pronounced physical gluten entanglement. Reducing fat levels in the recipe decreased the SDSEP levels of the baked cookies, indicating more protein cross‐linking during baking with lower fat levels. Our data show that the dispersed fat phase interferes with the formation of a gluten network during baking. Reducing the fat level in the recipe increased the intrinsic cookie break strength (from 39.5 to 100.3 N·cm³/g), which was related to more gluten cross‐linking.     

轻质土壤水分特征曲线估计的简便方法

以黄淮海平原封丘地区的潮土和风沙土为研究对象,根据大量的土壤基本物理性质和土壤持水数据,利用多元逐步回归分析方法,建立了轻质土壤在不同基质势下土壤含水量(θ)的传递函数模型,并进行了模型验证。结果表明,利用轻质土壤的基本物理性质估计其水分特征曲线是一种简便可行的方法,并且,在回归方程中,增加-30kPa含水量项可提高-30kPa以上土壤含水量的估计精度;增加-1500kPa含水量项可以明显提高-100kPa至-1500kPa间土壤含水量的估计精度。     

农业机械化对农业贡献率测算方法研究

测算农业机械化对农业生产的贡献份额,实践上有助于从总体上把握农业机械化的发展水平、发展潜力和趋势,对农业机械化事业的决策具有重要的参考价值;理论上研究产业系统单因素的贡献率具有学术意义。该文在分析国内外生产率理论和测算方法的基础上,设计了运用柯布－道格拉斯生产函数和项目有无比较法进行农业机械化对农业贡献率的测算方法。     

Effects of Cumin and Ginger as Antioxidants on Dough Mixing Properties and Cookie Quality

The effects of cumin and ginger as antioxidants on dough mixing properties and cookie quality were evaluated. Antioxidant activities in cookies were estimated by total phenolic compounds (TPC) contents and free radical scavenging activities. The cookie dough development was evaluated using Mixolab equipment which showed that addition of cumin did not change dough stability and C2, but decreased C3 and C4. While the addition of 5% ginger decreased dough stability (from 8.4 in the control sample to 6.7 min with 5% ginger addition), C2 (from 0.49 in the control sample to 0.31 N·m with 5% ginger addition), C3, and C4. Cookies formulated with addition of cumin and ginger had increased spread ratios, were softer, and had lower L* and b* values (were darker) than the control. Sensory analysis showed that cookies with cumin and ginger additions had overall acceptability similar to that of the the control with a slightly darker appearance, as confirmed by color determination. Using cumin and ginger significantly increased TPC contents from 78.5 in the control to 93.0 and 109.8 mg of gallic acid equivalent/100 g, respectively. Similar results were observed in the antioxidant activity measured by 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), which increased from 41.0% in the control to 51.5% and 64.6%, respectively, for cookies with 5% addition of cumin and ginger.     

基于Landsat 8 OLI数据的砒砂岩区生物量遥感估算

为了评价砒砂岩区植被生长状况和地上生物量的空间分布特征,采用Landsat 8 OLI和同期实测生物量数据对砒砂岩区生物量估算方法进行了研究。结果表明:(1)NDVI,RVI,SAVI,MSAVI与地上生物量(Above ground biomass,AGB)的相关性显著,其中MSAVI和AGB的相关性最高(R²=0.4416),SAVI次之(R²=0.3923),NDVI(R²=0.1375)和RVI(R²=0.1306)相对最低,NDVI和RVI在荒漠生态系统生物量遥感估算中并不是效果最佳的植被指数;(2)高斯低通3×3滤波核滤波的MSAVI与AGB的相关性(R²=0.4757)高于未滤波处理图像,滤波后建立的AGB-MSAVI_GLPF3估算模型平均相对误差MRE为13.41%,模型具有较高的估算精度;(3)遥感估算2019年砒砂岩研究区总AGB为9.2×10⁵t,其中AGB低值区的面积占比为13.03%,AGB中值区面积占比为47.56%,AGB高值区面积占比为39.41%。荒漠生态系统AGB与MSAVI的相关性显著,基于高斯低通滤波建立起的AGB-MSAVI_GLPF3模型可以较好地实现砒砂岩区AGB遥感估算。     

利用BP神经网络由特征气象要素预测土壤湿度

土壤湿度的实测数据量因地面观测网的稀疏不均和观测时间的不连续而十分有限,而其作为气象、农业、水文、环境等学科领域的重要研究内容,数据量的匮乏直接影响了研究工作的顺利进行。地面常规气象数据的观测频率较高(逐日/时),提供了丰富的大气及土壤状态信息,从地气交互作用的普遍性出发,对气象要素与土壤湿度之间的作用关系进行研究,拟借助人工神经网络良好的函数模拟能力,建立以多气象要素为网络输入、以土壤湿度为网络输出的BP神经网络。通过主成分分析筛选特征要素、选择训练函数、确定合理的隐层神经元个数等来精细化网络。以甘肃省2008年8、9月份的AB报(土壤湿度数据)和A报(气象观测数据)资料进行了实验,建立BP神经网络,最终获得了较好的土壤湿度预测结果。     

Using a Bayesian Hierarchical Linear Mixing Model to Estimate Botanical Mixtures

In grazing systems, estimating the dietary choices of animals is challenging but can be achieved using plant-wax markers, natural compounds that provide a signature of individual plants. If sufficiently distinct, these signatures can be used to characterize the makeup of a botanical mixture or diet. Bayesian hierarchical models for linear unmixing (BHLU) have been widely used for hyperspectral image analysis and geochemistry, but not diet mixtures. The aim of this study was to assess the efficiency of BHLU to estimate botanical mixtures. Plant-wax marker concentrations from eight forages found in Nebraska were used for simulating combinations of two, three, five and eight species. Also, actual forage mixtures were constructed in laboratory and evaluated. Analyses were performed using BHLU with 2 prior choices for forage proportions (uniform and Gaussian), 2 covariance structures (independent and correlated markers), stable isotope mixing models (SIMM), and nonnegative least squares (NNLS). Accounting for correlations between markers increased efficiency. Estimation error increased when Gaussian priors were used to model forage proportions. Performance of BHLU, SIMM, and NNLS was reduced with the more complex botanical mixtures and the limited number of markers. For simple mixtures, BHLU is a reliable alternative to NNLS for estimation of forage proportions. Supplementary materials accompanying this paper appear online.     

对开发建设项目水土保持投资概(估)算编制有关问题的探讨

开发建设项目水土保持投资概 (估 )算编制既要体现水土保持工程特点 ,又要与主体工程造价编制相结合。对在各行业工程造价编制规定及定额体系多样、标准不一的情况下 ,水土保持工程投资概 (估 )算编制中的有关问题进行了分析 ,并提出了建议     

~7Be示踪法估算土壤侵蚀速率模型计算结果比较

在总结现有7Be示踪法估算土壤侵蚀速率模型的基础上,通过坡耕地径流小区野外模拟降雨实测侵蚀资料,比较了Walling、杨明义和Wilson等所建的利用7Be示踪法估算土壤侵蚀速率模型的计算结果,并验证各模型的准确度。结果表明,对于不发生细沟侵蚀的小区,3个模型的计算值都有较高的准确度,但Wilson模型相对其它两个模型计算结果误差较大;对于发生细沟侵蚀的小区,Walling模型和杨明义模型估算坡面细沟间侵蚀量的绝对差值较小,但大于不发生细沟侵蚀小区的绝对差值;Wilson模型能够比较准确计算坡面的总侵蚀量,与实测值相比较,相对误差为3.59%～14.47%,不发生细沟侵蚀的小区相对误差大于发生细沟侵蚀的小区。随着侵蚀强度的增大,3个模型计算结果的准确度呈降低趋势。     

Effects of Temperature and Mechanical Input on Semisweet Biscuit (Cookie) Quality and Dough Characteristics

The effects of specific mechanical energy (SME) and dough temperature at the end of mixing (T_f) on semisweet biscuit dough characteristics and biscuit quality were studied using an experimental mixer fitted with monitoring devices. The fluid circulating in the double jacket of the mixing bowl was regulated at variable temperatures and mixed dough samples were prepared at T_f of 23, 30, and 37°C for three levels of SME input (20, 60 and 120 kJ/kg). Correlation analysis showed that semisweet biscuit length and thickness were independent quality parameters, influenced respectively by the T_f of dough and SME. Biscuit thickness and volume increased with SME input, but SME had no significant influence on the physicochemical characteristics of the dough. Biscuit length was related to the density and stickiness of the dough and to rheological behavior as assessed by fundamental and empirical measurements. A rise in dough temperature >35°C induced a dramatic increase in viscoelastic properties, leading to biscuit shrinkage. The increase of dough density with T_f seemed to be related to the melting of solid fat in the dough recipe. Melting of fat during mixing could also be a source of viscoelastic changes in the dough at T_f.     

基于VB 6.0的生态基流计算软件开发与应用

针对目前河流生态基流量尚无统一的计算平台,各种方法的计算和对比研究较为繁琐等问题,使用Visual Basic 6.0作为开发工具,开发出界面友好,操作简单,交互性强,包含12种水文学、水力学计算方法的河流生态基流量计算软件。该软件不仅简化了生态基流量计算步骤,而且便于不同方法之间的相互比较。使用该软件对渭河关中段进行了实例研究,结果发现不同方法的计算结果差别较大。选择8种单流量计算方法的平均值13.7m3/s作为渭河关中段的生态基流量,选择与研究区流量实际变化情况较为吻合的Texas法计算结果作为渭河关中段月生态基流量序列。该软件的开发与应用为今后河流生态基流量动态计算奠定了基础。     

Biaxial Extensional Viscosity of Sheeted Noodle Dough

The flows encountered during the sheeting process contain a more extensional component and more stretching than simple shear. Evaluating the properties of the extensional rheological flow of wheat flour dough is essential to better understand the sheeting process and the final quality of the product. Our results show that the curves of biaxial extensional viscosity versus extensional strain rate for dough from different wheat cultivars including Dark Northern Spring (DNS), Hard Red Winter (HRW), and Western White Wheat (WW) with protein contents of 7.81–18.09% and water contents of 32–40% could be discriminated. During a lubricated compression test, the sheeted dough displayed a region of extensional thickening followed by a region of mild extensional thinning, giving rise to an s-shaped extensional stress-strain rate curve. The higher degree of extensional thinning was exhibited for the sheeted dough prepared from the flour of DNS and HRW wheat mixture with an extensional thinning index of n = 0.65–0.74; while the lower degree of extensional thinning was displayed for the DNS wheat with an extensional thinning index of n = 0.89–0.96. The data of biaxial extensional viscosity (η_Bmax) versus water content and protein content could be described by power relationships. The results suggest that biaxial extensional viscosity can be a useful modeling and process design parameter that objectively represents the rheological properties during dough sheeting.     

Influence of Amylose Content on Cookie and Sponge Cake Quality and Solvent Retention Capacities in Wheat Flour

Reduced amylose wheat (Triticum æstivum L.) produces better quality noodles and bread less prone to going stale, while little is known about the relationships between amylose content and the quality of soft wheat baking products such as sugar snap cookies (SSC) and Japanese sponge cakes (JSC). Near‐isogenic lines developed from wheat cultivar Norin 61, differing in their level of granule‐bound starch synthase (Wx protein) activity, were used to produce wheat grains and ultimately flours of different amylose contents. These were tested with regard to their effect on soft wheat baking quality and solvent retention capacities (SRC). Amylose content was strongly correlated to cookie diameter (r = 0.969, P < 0.001) and cake volume (r = 0.976, P < 0.001), indicating that the soft wheat baking quality associated with SSC diameter and JSC volume were improved by an incremental increases in amylose content. Among the four kinds of SRC tests (water, sodium carbonate, sucrose and lactic acid), the water SRC test showed the highest correlation with amylose content, SSC diameter, and JSC volume. When the regression analysis was conducted between the nonwaxy and partial waxy isogenic lines that are available in commercial markets, only water SRC was significantly correlated to amylose content (r = –0.982, P < 0.001) among of four SRC tests. This suggests that, unlike udon noodle quality, high‐amylose content is indispensable in improving soft wheat baking quality, a process requiring less water retention capacity.