Temperature Sensitive Polymer

In this study, hydrogen sensing properties of nanoporous Pd films based on Anodic Aluminium Oxide (AAO) templates grown on a silicon substrate have been investigated at various temperatures (25–100°C) and hydrogen concentrations (100–1000 ppm) to determine the temperature-sensitivity relationship. For this purpose, a hexagonally shaped AAO template of approximately 50 nm in diameter and 700 nm in length with 80 nm interpore distances was fabricated using two-step anodization of an Al film deposited on an n-type (100) oriented oxidized Si substrate. Then, the nanoporous surface of the AAO template was used as a substrate for supporting a nanoporous Pd film of an approximately thickness of 60 nm. The morphologies of the AAO template and Pd film coated on the AAO template were studied mainly by Scanning Electron Microscopy (SEM). Hydrogen sensing properties of the nanoporous Pd film were measured using a resistance transient method. It was found that the sensor response of the nanoporous Pd films on the AAO template was better than the traditional Pd thin film sensors, the sensitivity of the sensor was approximately 1.8% for 1000 ppm H2, and the detection limit was lower than 100 ppm at room temperature. The highest sensitivity was measured at room temperature.

Information about the times of thermal breakthrough and subsequent rates of thermal drawdown in enhanced geothermal systems (EGS) is necessary for reservoir management, designing fracture stimulation and well drilling programs, and forecasting economic return. Thermal breakthrough in heterogeneous porous media can be estimated using conservative tracers and assumptions about heat transfer rates; however, tracers that undergo temperature-dependent changes can provide more detailed information about the thermal profile along the flow path through the reservoir. To be effectively applied, the thermal reaction rates of such temperature sensitive traces must be well characterized for the range of conditions that exist in geothermal systems. Reactive tracers proposed in the literature include benzoic and

ABStrAct: An electronic spreadsheet is described which helps users to design, equip and operate facilities for the mass rearing of insects for use in insect pest control programmes integrating the Sterile Insect Technique (SIT). The spreadsheet was designed based on experience ...

Radiometric performance of the Advanced Spectrometer for Thermal Emission and Reflection Radiometer (ASTER) is characterized by using acquired imagery data. Noise-equivalent reflectance and temperature, sensitivity (gain), bias (offset), and modulation transfer function (MTF) are determined for the visible and near-infrared (VNIR), the shortwave infrared (SWIR), and the thermal infrared (TIR) radiometers that constitute ASTER. The responsivity evaluated from onboard calibration

Temperature sensitivity of soil respiration (Q 10) is an important parameter in modeling the effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated that Q 10 has high spatial heterogeneity. However, most biogeochemical models still use a constant Q 10 in projecting future climate change and no spatial pattern of Q 10 values at large scales has been derived. In this study, we conducted an inverse modeling analysis to retrieve the spatial pattern of Q 10 in China ...

Cold temperatures are the cause of enormous agricultural losses, especially in sub-tropical and temperate grain crops. The reproductive period is a vital phase in the life cycle of all annual plants, and metabolism during this phase ultimately determines crop yield. Plants exposed to cold temperature during reproduction show reduced metabolic rates leading to low yields. In this review, we describe the effects of low temperature on various stages of the reproductive phase, from meiosis to grain filling, and temperature sensitivity of different reproductive organs. Cold temperature induces flower abortion, pollen and ovule infertility, causes breakdown of fertilization and affects seed filling, leading to low seed set and ultimately low grain yield. Physiological and metabolic bases of cold stress, including the role of phytohormones (especially ABA) and sugar-induced regulation are reviewed, and future research directions investigating molecular and metabolomic changes during the development of the gynoecium during cold stress suggested.

Sex steroid hormones are known to play a central role in vertebrate sex determination and differentiation. However, the tissues in which they are produced or received during development, especially around the period of sex determination of the gonads, have rarely been investigated. In this study, we identified the cDNA sequence, including the full-length of the coding region of cholesterol side-chain cleavage enzyme (P450scc), from the leopard gecko; a lizard with temperature-dependent sex determination. Embryonic expression analysis of two steroidogenic enzymes, P450scc and P450 aromatase (P450arom), and four sex steroid hormone receptors, androgen receptor, estrogen receptor α and β, and progesterone receptor, was subsequently conducted. mRNA expression of both steroidogenic enzymes was observed in the brain and gonads prior to the temperature-sensitive period of sex determination. The mRNAs of the four sex steroid hormone receptors were also detected in the brain and gonads at all stages examined. These results suggest the existence of a gonad-independent sex steroid hormone signaling system in the developing leopard gecko brain.

Enzyme activities are commonly measured in lab assays at a single standard temperature, which does not provide any information on their temperature sensitivity. Temperature is one of the primary controls on enzyme activities, yet few studies have explored how temperature drives enzyme activities in the environment. The temperature sensitivity of enzyme activity is controlled by the structure and conformation of the isoenzymes that constitute an environmental enzyme pool as well as physical and chemical interactions with soil minerals, clays, and organic matter. Yet, these complex relationships are typically represented by a simple Q 10 of 2. There is sufficient evidence to suggest that even for the same enzyme class, temperature sensitivities vary between soils, and even seasonally in a single site. We will explore the controls on enzyme temperature sensitivity and their importance for understanding seasonal patterns in soil processes and their potential responses to global change.

Accurate chromosome segregation requires the precise coordination of events during the cell cycle. Replicated sister chromatids are held together while they are properly attached to and aligned by the mitotic spindle at metaphase. At anaphase, the links between sisters must ...

Aims:  The aims of this communication were to study characterization of serogroups among Salmonella isolates and the relationship of antimicrobial resistance to serogroups. Multiple antimicrobial resistance (MAR) was performed on 189 Salmonella enterica isolates associated with 38 different serovars that were recovered from poultry and four types of indigenous vegetables.Methods and Results:  Disc diffusion analysis was performed with a selection of 10 different antimicrobial agents. Isolates recovered from indigenous vegetables showed 100% (134/134) resistant to erythromycin and followed by 42%, 34%, 19% for tetracycline, streptomycin and trimethroprim-sulfamethoxazole respectively. In general, 90·1% (50/55) and 56·7% (76/134) of Salmonella isolated from poultry and indigenous vegetables, respectively, exhibited MAR index more than 0·2.Conclusions:  Characterization of Salmonella isolates based on the MAR results indicated that poultry still remains as the main reservoir for multi-drug-resistant Salmonella. Four isolates from the indigenous vegetables showed the highest MAR index in this study. Further investigations need to be conducted to determine if Salmonella isolates recovered from indigenous vegetables were gaining more antimicrobial resistance.Significance and Impact of the Study:  The study enabled us to determine antimicrobial patterns and trends in Salmonella from poultry and indigenous vegetables in Malaysia.

Aims:  The aims of this communication were to study characterization of serogroups among Salmonella isolates and the relationship of antimicrobial resistance to serogroups. Multiple antimicrobial resistance (MAR) was performed on 189 Salmonella enterica isolates associated with 38 different serovars that were recovered from poultry and four types of indigenous vegetables.Methods and Results:  Disc diffusion analysis was performed with a selection of 10 different antimicrobial agents. Isolates recovered from indigenous vegetables showed 100% (134/134) resistant to erythromycin and followed by 42%, 34%, 19% for tetracycline, streptomycin and trimethroprim-sulfamethoxazole respectively. In general, 90·1% (50/55) and 56·7% (76/134) of Salmonella isolated from poultry and indigenous vegetables, respectively, exhibited MAR index more than 0·2.Conclusions:  Characterization of Salmonella isolates based on the MAR results indicated that poultry still remains as the main reservoir for multi-drug-resistant Salmonella. Four isolates from the indigenous vegetables showed the highest MAR index in this study. Further investigations need to be conducted to determine if Salmonella isolates recovered from indigenous vegetables were gaining more antimicrobial resistance.Significance and Impact of the Study:  The study enabled us to determine antimicrobial patterns and trends in Salmonella from poultry and indigenous vegetables in Malaysia.