Streptozotocin-Induced Diabetes Causes Changes in Serotonin-Positive Neurons in the Small Intestine in Pig Model

Serotonin (5-hydroxytryptamine or 5-HT) is an important neurotransmitter of the central and peripheral nervous systems, predominantly secreted in the gastrointestinal tract, especially in the gut. 5-HT is a crucial enteric signaling molecule and is well known for playing a key role in sensory-motor and secretory functions in the gut. Gastroenteropathy is one of the most clinical problems in diabetic patients with frequent episodes of hyperglycemia. Changes in 5-HT expression may mediate gastrointestinal tract disturbances seen in diabetes, such as nausea and diarrhea. Based on the double immunohistochemical staining, this study determined the variability in the population of 5-HT-positive neurons in the porcine small intestinal enteric neurons in the course of streptozotocin-induced diabetes. The results show changes in the number of 5-HT-positive neurons in the examined intestinal sections. The greatest changes were observed in the jejunum, particularly within the myenteric plexus. In the ileum, both de novo 5-HT synthesis in the inner submucosal plexus neurons and an increase in the number of neurons in the outer submucosal plexus were noted. The changes observed in the duodenum were also increasing in nature. The results of the current study confirm the previous observations concerning the involvement of 5-HT in inflammatory processes, and an increase in the number of 5-HT -positive neurons may also be a result of increased concentration of the 5-HT in the gastrointestinal tract wall and affects the motor and secretory processes, which are particularly intense in the small intestines.     

Drying characteristics of porous material immersed in a bed of hygroscopic porous particles fluidized under reduced pressure

A relatively large wet material was immersed in a fluidized bed of hygroscopic porous particle (silica gel beads) under reduced pressure. And then the drying characteristics were compared with those in the case of inert particle (glass beads). The comparison of drying characteristics is performed experimentally and theoretically. In calculation, the water transfer from the sample to the fluidized bed was considered. The calculation results are in good agreement with the experimental data. The effects of the operational conditions (the pressure in the drying chamber and the temperature of the drying gas) on the drying characteristics were also examined in both fluidizing particles.The drying finishes earlier in the case of hygroscopic porous particle than in the case of inert particle regardless of pressure in the drying chamber, since the water transfer from the sample facilitates the drying in the case of hygroscopic porous particles. The temperature decrement in drying appears in the case of inert particle. This phenomenon is also observed in the case of hygroscopic porous particle, but the decrement degree of the temperature is much smaller than that in the case of inert particle. The difference of the minimum temperature in the sample in drying between the cases of hygroscopic porous particle and inert particle is very slight for different pressures in the drying chamber.     

污泥生物炭中氮硫行为及环境效应研究进展

污泥生物炭中氮硫元素含量高,其氮硫行为和环境效应对全球气候变化的影响不容忽视。以往的研究中,研究者往往以富碳生物炭作为主要研究对象,关注碳对全球气候变化的行为和功效,而对氮硫元素的作用关注不够。本文从原始污泥基本性质到其热解过程,再到生物炭的老化,逐步对污泥生物炭整个生命周期内氮硫的行为及其环境效应研究进行综述,并对未来应注重开展的研究方向进行展望,为生物炭中氮硫元素固定、释放及与之关联的环境效应和温室气体排放控制研究提供理论基础。分析表明,污泥中氮元素含量普遍高于硫元素,且热解过程中氮比硫更容易转移至气相产物。氮硫元素随热解温度的增加,在三相产物中的分配都是炭中持续减少,油中先增后减,气中一直增加。高温（＞800℃）条件下,气相中的氮含量高于固相,而硫元素则仍然主要存在于固相中。污泥生物炭老化及其环境效应研究表明,污泥生物炭氮硫元素与土壤的相互作用及其温室效应问题在今后的研究中应引起重视。     

Evaluation of surfactant-aided degumming of vegetable oils by membrane technology

The first step in the process of vegetable oil refining is degumming, in which phospholipids and mucilaginous gums are removed that otherwise result in a low-grade oil. A membrane process is remarkably simple yet potentially offers many advantages in degumming. Studies were conducted on surfactant-aided membrane degumming with soybean and rapeseed oils in a magnetically stirred flat membrane batch cell with different types of microfiltration membranes. The reduction of phospholipids in soybean oil was in the range of 85.8–92.8% during the membrane process. The phosphorus content of membrane permeates of soybean oil was in the range of 20–58 mg/kg. Crude rapeseed oil contained higher amount of nonhydratable phospholipids and hence resulted in lower reduction in phospholipids, in the range of 66.4–83.2%. Addition of hydratable phospholipids could improve the efficiency of degumming in the membrane process without using any electrolyte, resulting in improvement of quality as well as quantity of the phospholipids.     

Sp7 Transgenic Mice with a Markedly Impaired Lacunocanalicular Network Induced Sost and Reduced Bone Mass by Unloading

The relationship of lacunocanalicular network structure and mechanoresponse has not been well studied. The lacunocanalicular structures differed in the compression and tension sides, in the regions, and in genders in wild-type femoral cortical bone. The overexpression of Sp7 in osteoblasts resulted in thin and porous cortical bone with increased osteoclasts and apoptotic osteocytes, and the number of canaliculi was half of that in the wild-type mice, leading to a markedly impaired lacunocanalicular network. To investigate the response to unloading, we performed tail suspension. Unloading reduced trabecular and cortical bone in the Sp7 transgenic mice due to reduced bone formation. Sost-positive osteocytes increased by unloading on the compression side, but not on the tension side of cortical bone in the wild-type femurs. However, these differential responses were lost in the Sp7 transgenic femurs. Serum Sost increased in the Sp7 transgenic mice, but not in the wild-type mice. Unloading reduced the Col1a1 and Bglap/Bglap2 expression in the Sp7 transgenic mice but not the wild-type mice. Thus, Sp7 transgenic mice with the impaired lacunocanalicular network induced Sost expression by unloading but lost the differential regulation in the compression and tension sides, and the mice failed to restore bone formation during unloading, implicating the relationship of lacunocanalicular network structure and the regulation of bone formation in mechanoresponse.     

Stress and strain state of concrete during freezing and thawing cycles

The objective of this work is to calculate the pressures, stresses, and strains induced into moist concrete during freezing and thawing. The applied theory is based on thermodynamics and the linear theory of elasticity. If no additional salts are dissolved in the pore water the inputs needed in the theory are relative humidity and temperature measured in the sample chamber and inside concrete and evaporable water amount in the pore structure. Theoretical results were compared with the test results made with two concretes cured under water or at 96% relative humidity. One of the concretes was air entrained and in the comparison concrete no air-entraining agents were used. In the test cylinders cured under water the largest tensional stresses in freezing occurred on the surface of the test cylinders both in the axial and tangential direction. The largest tensional stress was 2.2 MPa, both in air-entrained and in non air-entrained concretes. The largest tensional stresses in the warming phase took place at the end of the thawing period when the chamber temperature was around +5 °C. Then the maximum tension occurred in the middle of the concrete cylinder in the axial direction of the cylinder. This maximum tensional stress was over 2.5 MPa in the air-entrained concrete cured in the relative humidity of 96%. The thermodynamic pumping effect at the end of the thawing phase in every cycle can increase the pore water amount remarkably if free water or moisture is available on the surface of the structure or in the environment vapor. The thermodynamic pumping effect seems to be remarkably greater and more dangerous in air-entrained concretes.     

GAS MIXING IN SLUGGING AND TURBULENT FLUIDIZED BEDS

The gas phase mixing in a fluidized bed of glass beads (d_p = 0.362 mm) in the slugging and turbulent flow regimes has been studied in a 0.1 m-ID × 3.0 m high Plexiglas column.

The gas dispersion in the downstream of the bed has been described by a diffusion process with the axial and radial dispersion coefficients. The radial dispersion coefficient of the gas phase is nearly constant with the variation of gas velocity in the slugging flow regime, but it increases with an increase in gas velocity in the turbulent flow regime.

Appreciable backmixing of the gas phase is pronounced in the slugging flow regime whereas the lower gas backmixing is produced in the turbulent flow regime. The gas backmixing coefficient increases with an increase in gas velocity in the slugging flow regime, but it decreases slightly with an increase in gas velocity in the turbulent flow regime.

The radial mixing and backmixing coefficients of the gas in terms of Peclet numbers have been correlated with the relevant dimensionless parameters (U_g/U_mf, p_s/p_g, d_p/D_t).

The gas flow pattern in the bed has been well represented by a simplified model based on the two gas phases in the dilute and dense phases which are percolating through the bed in plug flow. The present model can predict the gas exchange coefficient between the phases, the fractions of the dilute phase, the interstitial gas in the dense phase, and the interstitial gas velocity in the bed.     

Possible Role of Crystal-Bearing Cells in Tomato Fertility and Formation of Seedless Fruits

Crystal-bearing cells or idioblasts, which deposit calcium oxalate, are located in various tissues and organs of many plant species. The functional significance of their formation is currently unclear. Idioblasts in the leaf parenchyma and the development of crystal-bearing cells in the anther tissues of transgenic tomato plants (Solanum lycopersicon L.), expressing the heterologous FeSOD gene and which showed a decrease in fertility, were studied by transmission and scanning electron microscopy. The amount of calcium oxalate crystals was found to increase significantly in the transgenic plants compared to the wild type (WT) ones in idioblasts and crystal-bearing cells of the upper part of the anther. At the same time, changes in the size and shape of the crystals and their location in anther organs were noted. It seems that the interruption in the break of the anther stomium in transgenic plants was associated with the formation and cell death regulation of a specialized group of crystal-bearing cells. This disturbance caused an increase in the pool of these cells and their localization in the upper part of the anther, where rupture is initiated. Perturbations were also noted in the lower part of the anther in transgenic plants, where the amount of calcium oxalate crystals in crystal-bearing cells was reduced that was accompanied by disturbances in the morphology of pollen grains. Thus, the induction of the formation of crystal-bearing cells and calcium oxalate crystals can have multidirectional effects, contributing to the regulation of oxalate metabolism in the generative and vegetative organs and preventing fertility when the ROS balance changes, in particular, during oxidative stresses accompanying most abiotic and biotic environmental factors.     

Molecular mechanisms of aging and immune system regulation in Drosophila

Aging is a complex process that involves the accumulation of deleterious changes resulting in overall decline in several vital functions, leading to the progressive deterioration in physiological condition of the organism and eventually causing disease and death. The immune system is the most important host-defense mechanism in humans and is also highly conserved in insects. Extensive research in vertebrates has concluded that aging of the immune function results in increased susceptibility to infectious disease and chronic inflammation. Over the years, interest has grown in studying the molecular interaction between aging and the immune response to pathogenic infections. The fruit fly Drosophila melanogaster is an excellent model system for dissecting the genetic and genomic basis of important biological processes, such as aging and the innate immune system, and deciphering parallel mechanisms in vertebrate animals. Here, we review the recent advances in the identification of key players modulating the relationship between molecular aging networks and immune signal transduction pathways in the fly. Understanding the details of the molecular events involved in aging and immune system regulation will potentially lead to the development of strategies for decreasing the impact of age-related diseases, thus improving human health and life span.     

Incubating superphosphate in ‘dry’soil can reduce its effectiveness

Single superphosphate was incubated for six months at 25°C in soil which had been subject to one of three moisture treatments. These were: dried in a glasshouse, dried at a constant temperature of 25°C, or moist soil. Phosphorus (P) effectiveness was then compared with effectiveness of P from freshly-applied superphosphate using yields of wheat (Triticum aestivum) and triticale (×Triticosecale) tops in pot experiments.Incubation in soil which had been dried at 25°C did not decrease the effectiveness of the P. Incubation in moist soil decreased it to about 20% of the effectiveness of freshly-applied P in one case and to about 50% in the other case. Incubation in soil which had been dried in a glasshouse also decreased its effectiveness. The decrease varied with conditions, but in two cases the P was 70% as effective as freshly-applied P, and in one case only 45% as effective. Presumably sufficient moisture was present in the soil dried in the glasshouse to enable water-soluble P present in the fertilizer to react with the soil.