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This study investigated the drying kinetics, specific energy consumption (SEC), color, and microstructural changes of sweet potato (Ipomoea batatas L.) based on experimental set-up of convective hot-air drying (CHAD), infrared drying (IRD), and combined infrared and convective-hot-air drying (IR-CHAD). The experiments were carried out at three air temperatures (50, 60 and 70 °C) and two IR intensities (1,100 and 1,400 W/m2) for sweet potato slices of 4 and 6 mm, respectively. The experimental results showed that the drying kinetics and mass transfer characteristic were significantly affected by drying air temperature, IR intensity, and thickness of the product. Combined IR-CHAD provided a higher drying rate with the shortest drying time when compared with CHAD and IRD. The IRD resulted in the lowest SEC values. The combined IR-CHAD resulted in 69.34–85.59% reduction in the SEC of CHAD. For combined IR-CHAD, an increase in the IR intensity at each temperature and slice thickness caused a decrease in the total SEC value. Dried sweet potato slices using CHAD and IR1-CHAD at intensity of 1,100 W/m2 showed the best color attributes. Combined IR-CHAD proved to be a very efficient drying method for the drying sweet potato and can be used for both industrial and commercial purposes. Practical applications: The rising concern regarding a more efficient drying method has rapidly increased the demand for novel drying techniques that can be used to produce premium dried sweet potato. However, most of these novel drying methods have not been thoroughly investigated and technical comparison with the common conventional methods have not been widely reported. In this respect, this study has shown that the novel combined IR-CHAD is a very promising drying method for the industrial drying of sweet potato. This drying method could reduce the over drying time by 63–74% and SEC by 85% when compared with drying using conventional CHAD method. The combined IR-CHAD at a lower IR intensity of 1,100 W/m2 could also provide dried sweet potato of better quality. The will amount to a reduction of the overall production cost which adversely could affect the prices of the final quality products.

A wheat harvest system simulation Model (WHSSM) was developed and used to investigate the economics of using aerated storage to minimise the impact of weather damage during wheat harvesting. The economic returns from grain production with and without aerated storage were examined using 15 years (1991–2005) of weather data for Goondiwindi, Queensland, Australia. The effect of different drier capacities was investigated. For continuous flow driers and batch driers, the optimum harvest moisture contents in the given farm setup were 14 and 13%, respectively. No positive effects from using aerated storage were achieved if growers use either high or medium capacity driers. Aeration cooling was however useful in supporting low-capacity drier with inadequate drying capacity or batch driers when the grain is harvested at high moisture contents. The results of this study highlight the importance of optimising the integration between agricultural machinery used, crop performance and perceived weather risk.

A simulation model for deep-bed batch drying of paddy was developed to predict the profiles of grain moisture content, grain temperature, air temperature and air humidity during the drying process. In order to evaluate the validity of this model, a laboratory-scale deep-bed batch dryer was designed and fabricated. Comprehensive drying experiments were carried out in three replications under different drying conditions with two independent drying variables, namely, drying air temperature (at two levels of 45 and 50^oC) and air mass flow rate (at three levels of 0.1, 0.16 and 0.22kgm^-^2s^-^1). Good agreement was found between the simulation results and the experimental data. After validation of the model, the dryer performance was optimized by minimizing specific energy consumption under identical moisture removal using the simulation model. Based on this criterion, the treatment with mass flow rate of 0.03kgm^-^2s^-^1 and air temperature of 35^oC was found to be the optimal drying condition.

Within highly mechanised agricultural productions systems such as the Australian cotton industry, operational energy inputs represent a major cost to the growers. In this paper, a framework to assess the operational energy inputs of various production systems and the relative performance of a grower within an adopted system is developed. It divides energy usage of cotton production into six broadly distinct processes, including fallow, planting, in-crop, irrigation, harvesting and post harvest. This enables both the total energy inputs and the energy usage of each production processes to be assessed. This framework is later implemented and incorporated into an online energy assessment tool (EnergyCalc). Using the developed software, seven farm audits are conducted. It is found that overall, depending on the management and operation methods adopted, the total energy inputs for these farms range from 3.7 to 15.2 GJ/ha of primary energy, which corresponds to $80–310/ha and 275–1404 kg CO 2 equivalent/ha greenhouse gas emissions. Among all the farming practices, irrigation water energy use is found to be the highest and is typically 40–60% of total energy costs. Energy use of the harvesting operation is also significant, accounting for approximately 20% of overall direct energy use. If a farmer moves from conventional tillage to minimum tillage, there is a potential saving of around 10% of the overall fuel used on the farm. Compared with cotton, energy uses by other crops are generally much smaller, due to less intensive management practices, and reduced irrigation requirements.

On-farm energy efficiency is becoming increasingly important in the context of rising energy costs and concerns over greenhouse gas (GHG) emissions. Energy audits are a crucial part of the overall energy and environmental management process. In this paper, the results of six on-farm energy audits are presented. It is shown that energy uses for these farms varied significantly, ranging from 1.29 GJ/ha for dryland sorghum production to 43.06 GJ/ha for avocado production. In some cases, nearly 80% of operational energy was expended on water harvesting and irrigation. The research shows that there is currently a strong need to develop standardised energy assessments and reporting protocols so that effective and widespread energy audits in agriculture can take place. It is further suggested that an energy audit in agriculture in the future may best start from irrigation, as it also consumes a considerable proportion of on-farm energy cost.

Several studies have quantified the energy consumption associated with crop production in various countries. However, these studies have not compared the energy consumption from a broad range of farming practices currently in practice, such as zero tillage, conventional tillage and irrigated farming systems. This study examines direct on-farm energy use for high value grain crops grown under different farming practices in Australia. Grain farming processes are identified and “typical” farming operation data are collected from several sources, including published and unpublished literature, as well as expert interviews. The direct on-farm energy uses are assessed for 27 scenarios, including three high value grain crops―wheat, barley and sorghum―for three regions (Northern, Southern and Western Australia) under three farming conditions with both dryland (both for conventional and zero-tillage) and irrigated conditions. It is found that energy requirement for farming operations is directly related to the intensity and frequency of farming operations, which in turn is related to tillage practices, soil types, irrigation systems, local climate, and crop types. Among the three studied regions, Western Australia requires less direct on-farm energy for each crop, mainly due to the easily workable sandy soils and adoption of zero tillage systems. In irrigated crops, irrigation energy remains a major contributor to the total on-farm energy demand, accounting for up to 85% of total energy use.

// Tingting Fang 1, * , Jiajia Lin 1, * , Yanru Wang 2 , Guangnan Chen 3 , Jing Huang 2 , Jie Chen 1 , Yan Zhao 1 , Ruixia Sun 1 , Chunmin Liang 2 , Binbin Liu 1 1 Key Laboratory of Carcinogenesis and Cancer Invasion (Fudan University), Ministry of Education, Shanghai, P. R. China 2 Laboratory of Tumor Immunology, Department of Anatomy, Histology, and Embryology, School of Basic Medical Sciences, Fudan University, Shanghai, P. R. China 3 The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, P.R. China * These authors have contributed equally to this work Correspondence to: Chunmin Liang, email: cmliang@fudan.edu.cn Binbin Liu, email: liu.binbin@zs-hospital.sh.cn Keywords: ADAM12, hepatocellular carcinoma, metastasis, TSPAN8 Received: October 06, 2015 Accepted: April 18, 2016 Published: June 01, 2016 ABSTRACT Recent evidence indicates that tetraspanin-8 (TSPAN8) promotes tumor progression and metastasis. In this study, we explored the effects of TSPAN8 and the molecular mechanisms underlying hepatocellular carcinoma (HCC) metastasis using various HCC cell lines, tissues from 149 HCC patients, and animal models of HCC progression. We showed that elevated expression of TSPAN8 promoted HCC invasion in vitro and metastasis in vivo , but did not influence HCC cell proliferation in vitro . Increased TSPAN8 expression in human HCC was predictive of poor survival, and multivariate analyses indicated TSPAN8 expression to be an independent predictor for both postoperative overall survival and relapse-free survival. Importantly, TSPAN8 enhanced HCC invasion and metastasis by increasing ADAM12m expression. We therefore conclude that TSPAN8 and ADAM12m may be useful therapeutic targets for the prevention of HCC progression and metastasis.

OBJECTIVE The aim of this study was to evaluate the effectiveness and accuracy of ultrasound-guided intraarticular and periarticular joint injections as compared with landmark-guided injections technique. METHODS A systematic literature search was performed in Medline, Web of Science, Embase, the Cochrane Central Register of Controlled Trials, reference lists of articles, and other sources. Only randomized controlled trials were included. Two reviewers independently selected and assessed each study for quality and extracted data. RESULTS Twelve randomized controlled trials were included in the meta-analysis. The results indicated that ultrasound-guided intraarticular and periarticular joint injections were more accurate than the landmark-guided injections (odds ratio, 0.36; 95% confidence interval, 0.22-0.60). Ultrasound-guided joint injections significantly decreased the visual analog scale scores at both 2 wks (mean difference, -9.57; 95% confidence interval, -13.14 to -5.99) (P < 0.00001) and 6 wks (mean difference, -14.21; 95% confidence interval, -18.20 to -10.21) (P < 0.00001) after injection. There was no statistically significant difference in visual analog scale score at 12 wks between ultrasound-guided and landmark-guided intraarticular and periarticular joint injections (mean difference, -4.42; 95% confidence interval, -11.71 to 2.87) (P = 0.23). CONCLUSIONS Intraarticular and periarticular injections using ultrasound guidance significantly improves the accuracy of joint injections, and there is a significant decrease in visual analog scale scores for up to 6 wks after injection. The effect of ultrasound guidance on the long-term outcome of joint injections is inconclusive. The improved accuracy of injections was associated with pain relief. The authors recommend routine ultrasound guidance for intraarticular and periarticular injections.

We demonstrated single-longitudinal-mode (SLM) lasing from a Fabry-Perot fiber laser cavity enabled by narrow bandwidth feedback from a high-Q (>106) on-chip SiN microring resonator, where the remaining sidemodes are further suppressed by a saturable absorber.

In this paper, the uni-axial tension of double-notched concrete specimens is analyzed by using a continuum plasticity model. As in a companion paper, the concept of minimization of the second-order energy is used as the criterion for judging a bifurcation. The energy computation is formulated in standard continuum plasticity. The analysis confirms that the unsymmetrical crack propagation (i.e. strains localizing on one side of the specimen) may occur either before or after the peak load. Influences on bifurcation of three factors, the notch depth to panel width, the local constitutive law, and the ratio of the panel width to panel length are investigated. A larger ratio of the notch depth to panel width, a steeper softening constitutive law, and a smaller ratio of the panel width to panel length, leads to an earlier bifurcation. These conclusions are consistent with those obtained from a simplified model.

Recently, hohlraum experiments were performed at the Shenguang-II (SG-II) laser facility [Lin et al., Chin. J. Lasers B10, Suppl. IV6 (2001)]. The measured maximum radiation temperature was 170 eV for the standard hohlraum and 150 eV for a 1.5-scaled one. This paper discusses the radiation temperature and laser hohlraum coupling efficiency in terms of a theoretical model [Phys. Plasmas 8, 1659 (2001)] and numerical simulation. A 2D laser–hohlraum coupling code, LARED-H [Chin. J. Comput. Phys. 19, 57 (2002)], gives a satisfactory coincidence with the measured time-resolved radiation temperature. Upon fitting the time-resolved curve, the theoretical model obtains the hohlraum coupling efficiency and, furthermore, the parameter n+s for the hohlraum wall material (Au) can be determined simultaneously, where n, s are the power exponents of temperature for the radiation Rosseland mean-free path and specific internal energy, respectively.

A critical issue for the plantation forest industry is the preservation and control of genetic material in order to facilitate the fertilisation process. This is best achieved by drying at low temperature and low humidity prior to extraction of seeds and pollen. For example, freshly picked green cones of Pinus radiata are best dried at 25°C, 20% relative humidity to avoid thermal damage and to prevent mould formation. Similar conditions are required for drying pollen catkins. These conditions can be met efficiently and reliably by the use of a dehumidifier dryer. This paper describes the design of such a drying system, including a review of the dehumidifier and the kiln design parameters necessary to achieve the required drying conditions. Performance data and commercial operating experience are also presented and analysed. The system is effective and reliable, and has increased both the speed of drying and the quality of the product.

This paper is devoted to a study of nonlinear stability of general linear methods for the numerical solution of delay differential equations in Hilbert spaces. New stability concepts are further introduced. The stability properties of (k,p,q)-algebraically stable general linear methods with piecewise constant or linear interpolation procedure are investigated. We also discuss stability of linear multistep methods viewed as a special subset of the class of general linear methods.

This paper presents detailed in situ experimental results for the performance of a commercial batch grain dryer under real operating conditions while drying barley. The distribution of key drying parameters of air temperature, relative humidity, airflow, grain moisture content, drying time and energy use are measured. For the two trials conducted, the overall cycle-averaged process thermal efficiency is 48·4 and 41·5%, respectively. This is achieved when the average initial moisture contents of the grain are, respectively, 15·7 and 17·2% and the highest plenum temperatures 41·4 and 34·0°C. During drying, unlike the stack-on temperatures, the exhaust air temperatures after the grain stack are fairly stable and only mildly affected by the variation of ambient conditions. After the initial heating period, the air enthalpy remains practically constant through the grain stack section. Close to the dryer centre, because of the presence of the auger, the air velocity is considerably lower than other parts of the dryer. The drying appears to be dominated by a drying front advancing through the grain stack. The reduction of grain moisture content is much faster during the last few hours of the drying process. The experiments highlight the importance of accurate measurement and representation of product moisture contents and airflow.

This entry presents an overview of alternative energy sources for agriculture. The potential of the adoption of various alternative energy sources including renewable energy in agriculture are evaluated.

Pumping systems are widely used in many applications, including municipal water/wastewater services, domestic, commercial and agricultural services, and industrial processes. They are a very significant energy user and consume nearly 20% of the world’s electrical energy demand. Therefore, improving the energy efficiency of pumping systems can provide great benefits in terms of energy, environment, and cost reduction. In this entry, an overview of pump classification with pros and cons of each type of pump is presented. The procedures used to design pumping systems are also outlined. This is then followed by a discussion on the opportunities for improving the energy efficiency of pumping systems during every stage of design, selection, operation, and maintenance.

Multiple sclerosis (MS) and osteoporosis (OP) affect a substantial proportion of the population. Accumulating evidence suggests that MS patients are at high risk for OP. We performed a meta-analysis to identify risk factors for lowered bone mineral density (BMD) in MS patients.We searched for articles within the Medline, Embase and Cochrane Library databases, published up to March 2014, pertaining to associations between MS and BMD. A total of 11 studies was included in the meta-analysis.The analysis indicated that MS patients have reduced lumbar spine, femur neck, and hip BMD compared with healthy controls (lumbar spine, standardized mean difference (SMD) = -0.76, 95% CI: -1.07, -0.45; femur neck, SMD = -0.56, 95% CI: -0.84, -0.29; and hip, SMD = -0.62, 95% CI: -0.96, -0.29). Further subgroup analysis revealed that a disease duration of7 years, total steroid dose during the disease of15 g, and an Expanded Disability Status Scale (EDSS) score of3, increased the risk of reduced BMD in the lumbar spine and femoral neck, but not in the hip. Meta-regression analysis did not explain the heterogeneity in the clinical characteristics or outcome definitions.Our meta-analysis suggests that MS patients have reduced overall BMD compared with healthy controls. Furthermore, disease duration (7 years), total steroid dose (15 g), and EDSS score (3) are risk factors for reduced BMD in MS patients.

Sustainability in agriculture and associated primary industries, which are both energy-intensive, is crucial for the development of any country. Increasing scarcity and resulting high fossil fuel prices combined with the need to significantly reduce greenhouse gas emissions, make the improvement of energy efficient farming and increased use of renewable energy essential. This book provides a technological and scientific endeavor to assist society and farming communities in different regions and scales to improve their productivity and sustainability. To fulfill future needs of a modern sustainable agriculture, this book addresses highly actual topics providing innovative, effective and more sustainable solutions for agriculture by using sustainable, environmentally friendly, renewable energy sources and modern energy efficient, cost-improved technologies. The book highlights new areas of research, and further R&D needs. It helps to improve food security for the rapidly growing world population and to reduce carbon dioxide emissions from fossil fuel use in agriculture, which presently contributes 22% of the global carbon dioxide emissions. This book provides a source of information, stimuli and incentives for what and how new and energy efficient technologies can be applied as effective tools and solutions in agricultural production to satisfy the continually increasing demand for food and fibre in an economically sustainable way, while contributing to global climate change mitigation. It will be useful and inspiring to decision makers working in different authorities, professionals, agricultural engineers, researchers, and students concerned with agriculture and related primay industries, sustainable energy development and climate change mitigation projects.

Sustainability in agriculture and associated primary industries, which are both energy-intensive, is crucial for the development of any country. Increasing scarcity and resulting high fossil fuel prices combined with the need to significantly reduce greenhouse gas emissions, make the improvement of energy efficient farming and increased use of renewable energy essential. This book provides a technological and scientific endeavor to assist society and farming communities in different regions and scales to improve their productivity and sustainability. To fulfill future needs of a modern sustainable agriculture, this book addresses highly actual topics providing innovative, effective and more sustainable solutions for agriculture by using sustainable, environmentally friendly, renewable energy sources and modern energy efficient, cost-improved technologies. The book highlights new areas of research, and further R&D needs. It helps to improve food security for the rapidly growing world population and to reduce carbon dioxide emissions from fossil fuel use in agriculture, which presently contributes 22% of the global carbon dioxide emissions. This book provides a source of information, stimuli and incentives for what and how new and energy efficient technologies can be applied as effective tools and solutions in agricultural production to satisfy the continually increasing demand for food and fibre in an economically sustainable way, while contributing to global climate change mitigation. It will be useful and inspiring to decision makers working in different authorities, professionals, agricultural engineers, researchers, and students concerned with agriculture and related primay industries, sustainable energy development and climate change mitigation projects.

This paper is concerned with the numerical solution of delay differential equations (DDEs). We focus on the error behaviour of general linear methods for stiff DDEs. A restricted type of interpolation procedure is considered for general linear methods. D -convergence properties of general linear methods with this interpolation procedure are investigated. Some extant results are unified.

This paper presents an economic model for analyzing the cost behavior of dehumidifier timber drying process. Various costs, including those of air drying, are identified and quantified. Reasonable assumptions are made to simplify the calculation process. For species of both softwoods and hardwoods, the optimum air drying strategies are investigated based on two scenarios of existing commercial dehumifier dryers and well-run high performance dehumidifier dryers. This paper finds that when the timber maximum air drying degrade rate is less than 5%, air drying adds significant value to the operation of dehumidifier dryers. This benefit accelerates with the extent of air drying. With the use of high performance dehumidifier dryers, the importance of air drying tends to decrease. The cost of air drying is very sensitive to both the assumed interest rate and timber maximum air drying degrade rate.

The main purpose of the present paper is to examine the asymptotic states of general linear methods for initial value problems of ordinary differential equations, and to extend the existing relevant results of Runge–Kutta methods, linear multistep methods by Humphries (1993) and Stuart and Humphries (1994). In particular, the existence of spurious steady solutions and period-2 solutions in the time step is studied, and the concepts of (strong and weak) R [1] -regularity and (weak) R [2] -regularity of general linear methods are introduced and studied. Some sufficient conditions for (strong and weak) R [1] -regularity and (weak) R [2] -regularity of such methods applied to initial value problems of ordinary differential equations with a globally Lipschitz condition or contractive or monotone condition are given.

The laser-solidified microstructural and compositional characterization and phase evolution during tempering at 963 K were investigated using an analytical transmission electron microscope with energy dispersive X-ray analysis. The cladded alloy, a powder mixture of Fe, Cr, W, Ni, and C with a weight ratio of 10:5:1:1:1, was processed with a 3 kW continuous wave CO2 laser. The processing parameters were 16 mm/s beam scanning speed, 3 mm beam diameter. 2 kW laser power, and 0.3 g/s feed rate. The coating was metallurgically bonded to the substrate, with a maximum thickness of 730 mu m, a microhardness of about 860 Hv and a volumetric dilution ratio of about 6%. Microanalyses revealed that the cladded coating possessed the hypoeutectic microstructure comprising the primary dendritic gamma-austenite and interdendritic eutectic consisted of gamma-austenite and M7C3 carbide. The gamma-austenite was a non-equilibrium phase with extended solid solution of alloying elements and a great deal of defect structures, i.e. a high density of dislocations, twins, and stacking faults existed in gamma phase. During high temperature aging, in situ carbide transformation occurred of M7C3 to M23C6 and M6C. The precipitation of M23C6, MC and M2C carbides from austenite was also observed.

Spectroscopic methods have been proposed to predict sugarcane quality in the field. There are different sample forms could be used to predict sugar content using spectroscopic methods; raw juice (RJ), clear juice (CJ), fibrated samples (FS), stalk cross sectional surface (SCS) and stalk skin (SS). Thus, this study was conducted to identify the optimum sample form for predicting quality using a low-cost and portable spectrometer. A total of 100 samples from each sample form were scanned using a visible-shortwave near infrared (Vis/SWNIR) spectrometer. The experiment was conducted under the same experimental setup and all data were treated using the same statistical methods. All spectral data were calibrated against brix value. The coefficient of determination (R2) for SCS, FS, CJ, SS and RJ were 0.88, 0.86, 0.84, 0.81 and 0.80, respectively. The study found that a Vis/SWNIR spectrometer could be used to predict sugar content from all sample forms.The stalk samples scanned on cross sectional surface was found to be the optimum sample form for quality prediction using a Vis/SWNIR spectrometer.

A controlled traffic no-till system is a cropping system that has a significant potential to improve soil health, sustainability and crop yield. A pilot experiment was conducted to compare soil chemical properties and crop yields between controlled traffic no-till and random traffic in an annual double-cropping area of the North China Plain from 2005 to 2010. The experiment was performed using three treatments: (1) controlled traffic no-till (NTCT); (2) random traffic no-till (NTRT); and (3) conventional tillage (CT). The NTCT treatment significantly improved soil organic matter and total N compared with both NTRT and CT treatments and remarkably increased available P compared with CT treatment in the surface soil layer (0–10cm), but no significant differences were found in soil pH compared with both NTRT and CT treatments. However, in the 10–20- and 20–30-cm soil profiles, soil organic matter, total N and available P were reduced after NTCT treatment when compared with those obtained after CT treatment. At 0–10cm soil depths, soil bulk density under NTCT and NTRT was higher than in CT, whereas the opposite was true at soil depths of 10–30cm. Overall, it was found that the 6-year mean maize yield of NTCT and NTRT treatments was 10.9% and 1.1% higher respectively than the CT treatment, whereas the winter wheat yield was 1.1% and 3.0% higher respectively compared with the CT treatment. NTCT appears to be an improvement over current farming systems in an annual double-cropping area of the North China Plain.

Bacillus subtilis initiates a complex developmental program that leads to the differentiation of the cell into a dormant endospore as the final step in a series of responses to nutrient depletion (for a review, see reference 18). Initiation of this differentiation is dependent upon phosphorylation of a response regulator, Spo0A (6). A complex signal transduction network comprising multiple kinases and phosphatases controls the level of phosphorylated Spo0A (Spo0A∼P) in the cells (6, 16). Spo0A∼P directly regulates expression of about 121 genes through either repression or activation (14) by binding specifically to a 7-bp DNA element, referred to as an 0A box (5′-TGNCGAA-3′) (24, 31). For example, Spo0A∼P binding directly represses the promoters for abrB, fruR, flgB, ftsE, sdp, and rocD (14, 17, 20). Other genes are directly activated by Spo0A∼P (14, 17, 20), and still others are activated by Spo0A∼P indirectly (14, 24). For example, the spo0H gene is repressed by AbrB until Spo0A∼P produced at the end of the exponential-growth phase represses abrB, relieving spo0H from AbrB-mediated repression (28). Moreover, Spo0A-activated promoters include those used by RNA polymerase containing the primary sigma factor, σA (e.g., spoIIG and spoIIE promoters) (20, 30) and those used by RNA polymerase containing the secondary sigma factor, σH (e.g., spoIIA and racA promoters) (2, 3, 29), which introduces additional combinations of control. In a strain mutant with respect to both kinA and kinB, two of the kinases that control the level of Spo0A∼P, a low level of Spo0A∼P accumulates that is sufficient to repress abrB transcription but insufficient for the activation of other Spo0A∼P-dependent genes required for sporulation (25). Therefore, the responses of some Spo0A-regulated promoters to Spo0A∼P appear to be more sensitive to Spo0A∼P levels than are the responses of other Spo0A-regulated promoters. A progressive accumulation of Spo0A∼P at the end of the exponential-growth phase produces a temporal pattern of responses by Spo0A-regulated promoters that reflects the specific response of each promoter to low- or high-threshold levels of Spo0A∼P (9). Thus, in addition to the combinations of controls described above, Spo0A-regulated promoters can be classified as either high- or low-threshold activated or repressed promoters (9). High-threshold promoters require a high level of Spo0A∼P to be activated or repressed, probably in part because the regulatory regions for these genes have relatively weak affinities for Spo0A∼P, whereas low-threshold promoters respond to a low level of Spo0A∼P because their regulatory regions have relatively high-affinity binding sites for Spo0A∼P (9). The progressive accumulation of Spo0A∼P allows cells to try less-drastic responses to nutrient depletion before commitment to differentiation into a dormant cell type. Moreover, Spo0A phosphorylation occurs in only a fraction of the population (7, 9, 10). Activation of Spo0A in this fraction of the population enables these cells to delay progression into sporulation by activating two operons, the sporulation killing factor (skf) and the sporulation delaying protein (sdp) operons (10). The products of these two operons prevent non-Spo0A∼P-expressing sibling cells from sporulating (sdp) and cause them to lyse (skf). The cells that have activated Spo0A early are then able to feed off the nutrients released, allowing them to continue growing and thus to delay their differentiation into dormant endospores. The skf promoter must be highly active to drive production of the secreted toxin, and it must be activated early in response to low levels of phosphorylated Spo0A (9, 10). However, its expression must be tightly regulated to prevent premature expression of the killing factor. Here we investigate how this promoter can be both highly active in response to low levels of Spo0A∼P and tightly controlled to prevent premature expression of the toxin. The sequence of the skf promoter, which is activated by low levels of Spo0A∼P (9), appears to indicate that Spo0A∼P may directly activate this promoter by a mechanism that is different from that of the spoIIG promoter, which has been studied more extensively (4, 12, 19-21, 23). Comparison of the relative affinities of Spo0A for the high- and low-threshold promoters shows that spoIIG has a Kd of 1,700 nM whereas the skf promoter has an apparent Kd value of 26 nM (9). A bioinformatics search identified two Spo0A binding sites (14); however, the search did not reveal other features of the skf promoter that would contribute to its positive regulation by low levels of Spo0A∼P. Here we report that skf is a σA-dependent promoter with multiple Spo0A binding sites, two of which span the −35 region. Moreover, upstream of the mapped transcriptional start site is a sequence that is very similar to the TRTGn motif found in extended −10 promoters in Bacillus subtilis (13, 26, 27), another feature that is not present in the spoIIG promoter. We show that this sequence is necessary for the high level of Spo0A-dependent promoter activity. We also describe other features of this promoter that are necessary for its tight regulation by Spo0A.

The Bacillus subtilis AT (anti-TRAP) protein inhibits the regulatory protein TRAP ( trp RNA-binding attenuation protein), thereby eliminating transcription termination in the leader region of the trp operon. Transcription of the AT operon is activated by uncharged tryptophan transfer RNA (tRNA Trp ). Here we show that translation of AT also is regulated by uncharged tRNA Trp . A 10-residue coding region containing three consecutive tryptophan codons is located immediately preceding the AT structural gene. Completion of translation of this coding region inhibits AT synthesis, whereas incomplete translation increases AT production. Tandem sensing of uncharged tRNA Trp therefore regulates synthesis of AT, which in turn regulates TRAP's ability to inhibit trp operon expression.

Background: Previously, we reported that MEPE/OF45 interacting with CHK1 protects CHK1 from degradation and cells from DNA damage-induced killing (Nucleic Acids Res, 37: 7447-7454 2009; Brit J Cancer 102: 862-866, 2010). To further investigate the nature of the CHK1 stabilization and its effects on cell sensitivity to DNA damage inducers, we designed this study to identify the key domain of CHK1 interaction with MEPE/OF45 and the key ubiquitination site of CHK1. Methods: GST-MEPE/OF45 was expressed in E. coli BL 21. HA-wild type CHK1 and various CHK1 truncated mutations were expressed in 293FT. GST pull-down assay was used to identify the key domain of CHK1 interacting with MEPE/OF45. To identify the ubiquitination site of CHK1, GFP-CHK1 with different Lys mutations were co-transfected with Ub-expression vector to 293FT, and 48 hours later, whole cell lysate were prepared, Western blot was carried out using a GFP monoclonal antibody to detect ubiquitinaed CHK1. The CHK1 half-life was used to detect the stabilization of CHK1 and a clonogenic assay was used to detect the sensitivity of cells to DNA damage inducers. Results: The key domain of CHK1 interacting with MEPE/OF45 and the key site of CHK1 ubiquitination were identified. Most importantly, the mutation of CHK1 with the main domain or key site affected CHK1 stabilization and cell sensitivity to DNA damage inducers. Conclusion: The interaction of CHK1 with MEPE/OF45 plays an important role in preventing CHK1 ubiquitination and; therefore, stabilizes CHK1, which further affects cell sensitivity to DNA damage inducers. Because CHK1 is an essential DNA damage response protein, these results provide valuable information for understanding the role of CHK1 in genomic integrity, which could be used for improving cancer treatment. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4059. doi:10.1158/1538-7445.AM2011-4059

In 1995, a new approach was presented to overcome the drawbacks of existing convergence theory for stiff initial value problems by Auzinger et al. (BIT 36 (4) (1996) 635–652), and illustrated by means of a convergence argument for the implicit Euler scheme. In the present paper, our intention is to obtain extending quantitive convergence results of BDF methods for a class of nonlinear strongly stiff problems and to illustrate further this new approach. Some numerical examples confirm our results.

Life cycle energy analysis (LCEA) of eight residential buildings in and around Brisbane, Queensland, Australia, is undertaken in this study. Energy used in all three phases of construction, operation and demolition are considered. It is found that the main contribution to the operational energy in residential buildings is from use of general appliance. The choice of building materials is shown to have significant effects on the embodied energy for the production, construction, maintenance and demolition phases. From this study, it is shown that the embodied energy may vary from 10% to 30%, while the operational energy may vary from 65% to 90%. The demolition energy generally accounts for less than 4% of life cycle energy.

This paper is concerned with the numerical solution of delay dierential equations (DDEs). We focus on the stability behaviour and error analysis of one-leg methods with respect to nonlinear DDEs. The new concepts of GR-stability, GAR-stability and weak GAR-stability are introduced. It is proved that a strongly A-stable one-leg method with linear interpolation is GAR-stable, and that an A-stable one-leg method with linear interpolation is GR-stable, weakly GAR-stable and D-convergent of order s, if it is consistent of order s in the classical sense. c 1999 Elsevier Science B.V. All rights reserved. AMS classication: 65L06; 65L20