An optimization model for energy crop supply

In this article we describe an optimization model, a mixed integer program, to determine the optimal locations and capacity sizes of biomass‐based facilities in energy crop supply chains, and demonstrate its use using data for Great Britain. We show the utility of the model for planning the optimal locations of biomass‐based facilities by investigating the supply of feedstock from Miscanthus for Combined Heat and Power (CHP) in Great Britain, based on data of current electricity demand. Results show that CHP cost directly influences its optimal location, and the price of bioelectricity from Miscanthus. At the coarse spatial resolution of the available energy demand data, the sale price of Miscanthus does not greatly influence the quantity of Miscanthus sold in Great Britain. Only when the hypothetical sale price of Miscanthus was closer to CHP cost, was the quantity of Miscanthus sold influenced by the variation in the sale price of Miscanthus. In future, we will apply the model using electricity and heat demand data at fine spatial scale currently being located, which will allow the implications of local production of Miscanthus for CHP to be explored.     

The Use of Combined Classifiers in Medical Functional Diagnostics

In otological and ophthalmological functional diagnostics it is typical to record for a certain individual several similar biopotentials under different conditions of stimulation and/or to collect various potentials for the same individual. Since the combination of these different data collected from a patient is of interest, coupling of the classification results obtained for each single data set seems desirable. Based on sample classifiers, obtained by linear discriminance analysis, of acoustically or visually evoked potentials from selected patients an algorithm is proposed for their coupling, which logically links the various rules of allocation and is based on the principle of assignment by highest likelihood. Furthermore, the procedure may be modified by inclusion of corresponding confidence intervals for the determined allocation frequencies. The results obtained for the groups of patients investigated show a considerable improvement of classification as judged from the error rates being distinctly reduced after the coupling.     

Mass cultivation of Nannochloropsis sp. in annular reactors

A study was made on the mass cultivation of Nannochloropsis sp. in newly designed annular reactors operated under natural, artificial or combined illumination. The annular reactor consists of two 2-m-high Plexiglas cylinders of different diameter placed vertically one inside the other so as to form an annular culture chamber. Artificial illumination is supplied by lamps placed inside the inner cylinder. Two annular reactors of different diameter (50 and 91 cm), light path (4.5 and 3.0 cm) and illuminated surface area (5.3 and 9.3 m²) were experimented with. The effect of two different artificial light sources (fluorescent tubes and metal halide lamps) on culture productivity was investigated in both systems. The highest productivity on a per reactor basis (about 34 g (d. wt) reactor^–1 24 h^–1) was achieved with the larger reactor illuminated by a 400-W metal halide lamp. From February to May a 91-cm reactor illuminated only with natural light was operated in parallel with a 91-cm reactor subjected to combined illumination. Under natural illumination productivity increased from 16.6 g (d. wt) reactor^–1 d^–1 in February to 34.1 g (d. wt) reactor^–1 d^–1 in May. Under combined illumination productivity was 41.3 g (d. wt) reactor^–1 d^–1 in February and increased up to 48.3 g (d. wt) reactor^–1 d^–1 in May. Although the culture exposed to combined illumination always attained higher yields, the productivity gap between the two cultures decreased gradually along the season as solar radiation and minimum night temperatures increased. A 1200-L plant made of ten 50-cm annular reactors was set up and operated for two years with combined illumination yielding an average of 270 g of dry Nannochloropsis sp. biomass per day. More than 2000 L of concentrate suspension (50 g (d. wt) L^–1) of Nannochloropsis sp. were produced and successfully used by fish hatcheries as live feed for rotifers and for rearing seabream larvae with the green-water technique. This study indicates that the annular reactor can be profitably used for long-term cultivation of Nannochloropsis in temperate climates. Besides reliability and ease of operation, the main advantage of the system is that it can be used under natural illumination, yet artificial light can be also supplied to maintain high productivity levels in winter or on cloudy days.     

Perforation of ABS pipes by boring bivalve Martesia striata: a case study

Acrylonitrile butadiene styrene (ABS) pipes are considered to be immune for boring organisms. However, inspection of the offshore cooling water conduits of Lumut combined cycle power plant, Malaysia show that ABS pipes may not necessarily be immune for wood boring pholads, Martesia striata. M. striata caused heavy damage by drilling holes in ABS pipes used (about 5 years) for transportation of hypochlorite from the station towards the intake domes. Hole sizes ranged from 3 to 19 mm² with an average of 11 mm². Unlike other boring animals (e.g. Lithophaga), M. striata penetration is not assisted by chemical dissolution of the substrates and therefore, attack is not limited to calcium carbonate substrates. In this context, material like low dense concrete and rocks, wood, PVC, ABS, etc. is subject to attack of M. striata. It is unknown which synthetic polymerics can be expected to be completely immune for boring bivalves.     

The efficient physiological strategy of a novel tomato genotype to adapt to chronic combined water and heat stress

• Climate change is increasing the frequency of high temperature shocks and water shortages, pointing to the need to develop novel tolerant varieties and to understand the mechanisms employed to withstand combined abiotic stresses.
• Two tomato genotypes, a heat-tolerant Solanum lycopersicum accession (LA3120) and a novel genotype (E42), previously selected as a stable yielding genotype under high temperatures, were exposed to single and combined water and heat stress. Plant functional traits, pollen viability and physiological (leaf gas exchange and chlorophyll a fluorescence emission measurements) and biochemical (antioxidant content and antioxidant enzyme activity) measurements were carried out. A Reduced Representation Sequencing approach allowed exploration of the genetic variability of both genotypes to identify candidate genes that could regulate stress responses.
• Both abiotic stresses had a severe impact on plant growth parameters and on the reproductive phase of development. Growth parameters and leaf gas exchange measurements revealed that the two genotypes used different physiological strategies to overcome individual and combined stresses, with E42 having a more efficient capacity to utilize the limiting water resources. Activation of antioxidant defence mechanisms seemed to be critical for both genotypes to counteract combined abiotic stresses. Candidate genes were identified that could explain the different physiological responses to stress observed in E42 compared with LA3120.
• Results here obtained have shown how new tomato genetic resources can be a valuable source of traits for adaptation to combined abiotic stresses and should be used in breeding programmes to improve stress tolerance in commercial varieties.

     

DTP—rHB联合疫苗的研制

本文对制备ＤＴＰ—ｒＨＢ联合疫苗的实验条件进行了初步探索，并优选最佳配方制备的三批连续中试产品经安全、效力试验测定，结果表明，联合疫苗中各组分均能达到相应规程要求，抗原间无干扰作用，相容性好。联合疫苗中的ｒＨＢ免疫应答较单价苗明显提高（Ｐ＜ ０．０５），有增强作用。ＨＢｓＡｇ含量以２０ μｇ／ｍ ｌ为宜，稳定性试验证明，该联合疫苗质量稳定、安全、有效。     

Multitraits evaluation of a Solanum pennellii introgression tomato line challenged by combined abiotic stress

• Rising daily temperatures and water shortage are two of the major concerns in agriculture.
• In this work, we analysed the tolerance traits in a tomato line carrying a small region of the Solanum pennellii wild genome (IL12-4-SL) when grown under prolonged conditions of single and combined high temperature and water stress.
• When exposed to stress, IL12-4-SL showed higher heat tolerance than the cultivated line M82 at morphological, physiological, and biochemical levels. Moreover, under stress IL12-4-SL produced more flowers than M82, also characterized by higher pollen viability. In both lines, water stress negatively affected photosynthesis more than heat alone, whereas the combined stress did not further exacerbate the negative impacts of drought on this trait. Despite an observed decrease in carbon fixation, the quantum yield of PSII linear electron transport in IL12-4-SL was not affected by stress, thereby indicating that photochemical processes other than CO₂ fixation acted to maintain the electron chain in oxidized state and prevent photodamage. The ability of IL12-4-SL to tolerate abiotic stress was also related to the intrinsic ability of this line to accumulate ascorbic acid.
• The data collected in this study clearly indicate improved tolerance to single and combined abiotic stress for IL12-4-SL, making this line a promising one for cultivation in a climate scenario characterized by frequent and long-lasting heatwaves and low rainfall.

     

A systematic framework for using membrane metrics for strain engineering

The cell membrane plays a central role in the fitness and performance of microbial cell factories and therefore it is an attractive engineering target. The goal of this work is to develop a systematic framework for identifying membrane features for use as engineering targets. The metrics that describe the composition of the membrane can be visualized as “knobs” that modulate various “outcomes”, such as physical properties of the membrane and metabolic activity in the form of growth and productivity, with these relationships varying depending on the condition. We generated a set of strains with altered membrane lipid composition via expression of des, fabA and fabB and performed a rigorous characterization of these knobs and outcomes across several individual inhibitory conditions. Here, the knobs are the relative abundance of unsaturated lipids and lipids containing cyclic rings; the average lipid length, and the ratio of linear and non-linear lipids (L/nL ratio). The outcomes are membrane permeability, hydrophobicity, fluidity, and specific growth rate. This characterization identified significant correlations between knobs and outcomes that were specific to individual inhibitors, but also were significant across all tested conditions. For example, across all conditions, the L/nL ratio is positively correlated with the cell surface hydrophobicity, and the average lipid length is positively correlated with specific growth rate. A subsequent analysis of the data with the individual inhibitors identified pairs of lipid metrics and membrane properties that were predicted to impact cell growth in seven modeled scenarios with two or more inhibitors. The L/nL ratio and the membrane hydrophobicity were predicted to impact cell growth with the highest frequency. We experimentally validated this prediction in the combined condition of 42 °C, 2.5 mM furfural and 2% v/v ethanol in minimal media. Membrane hydrophobicity was confirmed to be a significant predictor of ethanol production. This work demonstrates that membrane physical properties can be used to predict the performance of biocatalysts in single and multiple inhibitory conditions, and possibly as an engineering target. In this manner, membrane properties can possibly be used as screening or selection metrics for library- or evolution-based strain engineering.     

Mathematical models of bacterial growth,inhibition and death under combined stress conditions

Summary In this report we review the history of growth theories. We show how classical growth models may be derived as special cases of a generic growth rate equation. We show how growth models may be modified to represent survival data. We use linear combinations of growth and survival models to represent complex growth/survival curves and give practical examples utilizing nonlinear regression analysis. We show that traditional methods of estimating D values are inappropriate for complex, multiphasic growth/survival data. We show how such data may be modeled mathematically and illustrate methods for estimating true D values from such data.     

Moderate walnut consumption improved lipid profile,steroid hormones and inflammation in trained elderly men: a pilot study with a randomized controlled trial

The present study aimed to investigate the effect of walnut consumption on lipid profile, steroid hormones and inflammation in trained elderly men performing concurrent (resistance and endurance) training. Twenty healthy elderly males were divided into two matched groups, in a randomized controlled trial, that trained three sessions per week: concurrent training + dietary walnut consumption (15 g/day for six weeks, CTW: n = 10); concurrent training + control diet (CT: n = 10). Fasting blood samples were taken 48 hours before and after intervention for biochemical assessments. levels of high-density lipoprotein (HDL) increased only in CTW compared to baseline (19.8%, p < 0.01). Total cholesterol (TC), low-density lipoprotein (LDL) and triglyceride (TG) levels significantly decreased only for CTW (i.e., 13%, 18%, and 18.5% at p < 0.01 for all). Testosterone (T) increased after the training compared to pre-training for CTW and CT (10.3%, p < 0.01, 4.27% p < 0.05, respectively), but the increase was significantly higher in CTW (p < 0.05). Serum cortisol (C) was lower for CTW compared to CT (p < 0.01). C-reactive protein (CRP) decreased in CTW in comparison with CT. The present study revealed that 6-week moderate walnut supplementation (15 g/day) improved lipid profile, steroid hormones and systematic inflammation in aged men performing concurrent training. These findings could be attributable to the potential effect of polyunsaturated fatty acids (PUFA) contained in walnut (linoleic acid, n-6; linolenic acid, n-3).