A kinetic model for predicting shelf-life of fresh extruded rice-shaped kernels(FER)

Fresh extruded rice-shaped kernels(FER) are remoulded rice products from cereals or seed flours, which have the advantages of safety, nutrition, health and time saving. However, the finished products are easy to react with oxygen, so it is necessary to develop a fast, simple and reliable approach to monitor and predict the shelf-life of FER. A comprehensive mathematical model of FER shelf-life prediction was developed using a dynamic modelling approach based on real supply chain conditions. This predictive model was developed to determine four key indexes including acid value, iodine blue value, water uptake ratio and peroxide value. The results showed that when the peroxide value was 1.6849, the FER lost its edible value, nutritional value and commodity value. Moreover, the acid value and peroxide value of FER were used to establish a first-order kinetic model, and the iodine blue value of FER was suited for a zero-order kinetic model. The validation experiment of predicted and measured shelf life showed that the relative error was 3.12%, which was less than 5%. Therefore, this kinetic model could be used to predict the shelf-life of FER quickly and conveniently. The kinetic-based shelf-life prediction model proposed in this study is rapid and practical, providing theoretical basis and guidance for the establishment of quality monitoring and quality evaluation systems of FER during the production, storage, transport and marketing.

Promotional effects of Er incorporation in CeO_2(ZrO_2)/TiO_2 for selective catalytic reduction of NO by NH_3

A series CeO2（ZrO2）/TiO2 catalysts were modified with Er using a sol-gel method.The catalytic activity of the obtained catalysts in the selective catalytic reduction（SCR） of NO with NH3 was investigated to determine the appropriate Er dosage.The catalysts were characterized using X-ray diffraction,N2 adsorption,NH3 temperature-programmed desorption,H2 temperature-programmed reduction,photoluminescence spectroscopy,electron paramagnetic resonance spectroscopy,and X-ray photoelectron spectroscopy.The results showed that the optimum Er/Ce molar ratio was 0.10;this catalyst had excellent resistance to catalyst poisoning caused by vapor and sulfur and gave more than 90% NO conversion at 220–395 ℃ and a gas hourly space velocity of 71 400 h^-1.Er incorporation increased the Ti^3＋ concentrations,oxygen storage capacities,and oxygen vacancy concentrations of the catalysts,resulting in excellent catalytic performance.Er incorporation also decreased the acid strength and inhibited growth of TiO2 and CeO2 crystal particles,which increased the catalytic activity.The results show that high oxygen vacancy concentrations and oxygen storage capacities,large amounts of Ti^3＋,and low acid strengths give excellent SCR activity.

Influence of hypoxia-inducible factor 1-alpha on neuronal apoptosis in a rat model of hypoxia-or hypoxia-ischemia-induced brain injury

BACKGROUND： In addition to neuroprotective genes, the targeted genes of hypoxia-inducible factor 1α （HIF-1α） include pro-apoptotic genes. However, the influence of HIF-1α on neuronal apoptosis in hypoxia-ischemia remains poorly understood. OBJECTIVE： To investigate the relationship between HIF-1α expression and neuronal apoptosis in hypoxia or hypoxia-ischemia brain injury and to determine the role of HIF-1α in regulating neuronal apoptosis. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed at the Laboratory of Children Neurology of Sichuan University between May 2006 and May 2007. MATERIALS： In situ cell death detected kit was provided by Roche, USA; rabbit anti-mouse HIF-1α polyclonal antibody was purchased from Santa Cruz Biotechnologies, USA; rabbit anti-mouse cleaved caspase-3 polyclonal antibody was purchased from Chemicon, USA. METHODS： A total of 36 Sprague Dawley rats aged 10 days were randomly assigned to 3 groups： sham-surgery, hypoxia, and hypoxia-ischemia, with 12 rats per group. The rats were treated at 3 time points： 4, 8, and 24 hours, with 4 rats per time point. In the hypoxia-ischemia group, the right common carotid artery was exposed and permanently ligated through a midline cervical incision. A 2.5-hour exposure to hypoxia （8% O2/92% N2） was used to induce hypoxia-ischemia injury. In the hypoxia group, rats were exposed to hypoxia without ligation of the common carotid artery. In the sham-surgery group, the common carotid artery was exposed without ligation or hypoxia. MAIN OUTCOME MEASURES： Histopathological changes, HIF-1α and activated caspase-3 protein expression, integrated optical density of positive cells, and apoptosis-positive cells. RESULTS： Hematoxylin and eosin staining showed that neuronal degeneration and edema was most prominent at 24 hours after hypoxia-ischemia. HIF-1α protein expression was significantly upregulated at 4 hours, peaked at 8 hours, and decreased at 24 hours after hypoxia or hypoxia-ischemia. HIF-1α protein expression was significant greater in the hypoxia and hypoxia-ischemia groups compared with the sham-surgery group （P 〈 0.01）. Activated caspase-3 protein expression began to increase at 4 and 8 hours following hypoxia or hypoxia-ischemia and was significantly upregulated at 24 hours. Activated caspase-3 protein expression remained at low levels in the sham controls compared with the hypoxia and hypoxia-ischemia groups （P〈 0.01）. TUNEL staining showed that the number of apoptotic cells significantly increased at 24 hours after hypoxia or hypoxia-ischemia. In addition, HIF-1α protein expression was greater in the hypoxia group compared with the hypoxia-ischemia group at the same time point （P 〈 0.05）. However, activated caspase-3 expression and the number of TUNEL-positive cells were less in the hypoxia group compared with the hypoxia-ischemia group at the same time point （P〈 0.05）. CONCLUSION： HIF-1α played a neuroprotective role following hypoxia-ischemia brain injury.

Study on Optimizing Nutrition and Fermentation Conditions for Compound <i>Bacillus spp.</i>

In order to improve the spore yield of compound Bacillus spp. (B. amyloliquefaciens, B. laterosporus and B. megaterium), the effects of nutrient conditions including carbon source, nitrogen source, mineral salt and fermentation conditions including the inoculum age, inoculation amount, loading volume of liquid and initial pH on the spore yield were studied. The results indicated that the optimized medium was glucoses 20 g/L, soybean meal 30.0 g/L, K2HPO4 1.0 g/L;fermentation temperature is 37&#8451;, the inoculum age 12 h, initial pH 7.0, 2% inoculation amount, loading volume of liquid 20 mL/250 mL. Under the optimized conditions of culture medium and fermentation for compound Bacillus spp., spore yield was 10.24 times more than the initial medium, and the spore formation rate reached more than 90%.

A new cell death program regulated by toll-like receptor 9 through p38 mitogen-activated protein kinase signaling pathway in a neonatal rat model with sepsis associated encephalopathy

Background:Sepsis,a serious condition with high mortality,usually causes sepsis associated encephalopathy(SAE)that involves neuronal cell death.However,the cell death programs involved and their underlying mechanisms are not clear.This study aimed to explore the regulatory mechanisms of different cell death programs in SAE.Methods:A neonatal rat model of SAE was established by cecal ligation and perforation.Survival rate and vital signs(mean arterial pressure and heart rate)were monitored,nerve reflexes were evaluated,and cortical pathological changes were observed by hematoxylin and eosin staining.The expression of pyroptosis,apoptosis,and necroptosis(PANoptosis)-related proteins,mitogen-activated protein kinase(MAPK),and its upstream regulator toll-like receptor 9(TLR9)were detected.The expression of TLR9 in neurons was observed by immunofluorescence staining.The ultrastructure of neurons was observed by transmission electron microscope.Results:First,PANoptosis was found in cortical nerve cells of the SAE rats.Meanwhile,the subunits of MAPKs,p38 MAPK,Jun N-terminal kinase,and extracellular signal-regulated kinase(ERK)were activated.After pharmacologically inhibiting each of the subunits,only p38 MAPK was found to be associated with PANoptosis.Furthermore,blocking the p38 MAPK signaling pathway activated necroptosis but inhibited apoptosis and pyroptosis.When necroptosis was pharmacologically inhibited,apoptosis and pyroptosis were reactivated.Finally,we found that the expression of TLR9,a regulator of MAPKs,was significantly increased in this model.After down-regulation of TLR9,p38 MAPK,and ERK signaling pathways were inhibited,which led to the inhibition of PANoptosis.Further analysis found that down-regulation of TLR9 improved the survival rate and reduced the pathological changes in SAE rats.Conclusions:Our study showed that the programs comprising PANoptosis are activated simultaneously in SAE rats.TLR9 activated PANoptosis through the p38 MAPK signaling pathway.TLR9 may work as a potential target for SAE treatment.

Optimal layout model of feeder automation equipment oriented to the type of fault detection and local action

In feeder automation transformation there are difficulties in equipment and location selection.To help with this,an optimal layout model of feeder automation equipment oriented to the type of fault detection and local action is pro-posed.It analyzes the coordination relationship of the three most common types of automation equipment,i.e.,fault indicator,over-current trip switch and non-voltage trip switch in the fault handling process,and the explicit expres-sions of power outage time caused by a fault on different layouts of the above three types of equipment are given.Given constraints of power supply reliability and the goal of minimizing the sum of equipment-related capital invest-ment and power interruption cost,a mixed-integer quadratic programming model for optimal layout is established,in which the functional failure probability of equipment is linearized using the 3δprinciple in statistics.Finally,the basic characteristics of the proposed model are illustrated by different scenarios on the IEEE RBTS-BUS6 system.It can not only take into account fault location and fault isolation to enhance user power consumption perception,but also can guide precise investment to improve the operational quality and efficiency of a power company.