Miracle-dz/UniFAR-FTUs huggingface dataset:
Activation and inactivation of single calcium channels in snail neurons

Activation and inactivation properties of Ca currents were investigated by studying the behavior of single Ca channels in snail neurons. The methods described in the previous paper were used. In addition, a zero- phase digital filter has been incorporated to improve the analysis of latencies to first opening, or waiting times. It was found that a decrease in the probability of single channel opening occurred with time. This was especially marked at 29 degrees C and paralleled the inactivation observed in macroscopic currents. The fact that a single channel was observed means that there is a significant amount of reopening from the "inactivated" state. Small depolarizations at 18 degrees C showed little inactivation. From these measurements, histograms of single channel open, closed, and waiting times were analyzed to estimate the rate constants of a three-state model of activation. Two serious discrepancies with the model were found. First, waiting time distributions at -20 mV were slower than those predicted by parameters obtained from an analysis of the single channel closed times. Second, it was shown that the time and the magnitude of the peak of the waiting time histogram were inconsistent with a three-state model. It is concluded that a minimum of four states are involved in activation. Some four-state models may be eliminated from further consideration. However, a comprehensive model of Ca channel kinetics must await further measurements.
Atmospheric water vapor as driver of litter decomposition in Mediterranean shrubland and grassland during rainless seasons

Litter production in many drought‐affected ecosystems coincides with the beginning of an extended season of no or limited rainfall. Because of lack of moisture litter decomposition during such periods has been largely ignored so far, despite potential importance for the overall decay process in such ecosystems. To determine drivers and extent of litter decay in rainless periods, a litterbag study was conducted in Mediterranean shrublands, dwarf shrublands and grasslands. Heterogeneous local and common straw litter was left to decompose in open and shaded patches of various field sites in two study regions. Fresh local litter lost 4–18% of its initial mass over about 4 months without rainfall, which amounted to 15–50% of total annual decomposition. Lab incubations and changes in chemical composition suggested that litter was degraded by microbial activity, enabled by absorption of water vapor from the atmosphere. High mean relative humidity of 85% was measured during 8–9 h of most nights, but the possibility of fog deposition or dew formation at the soil surface was excluded. Over 95% of the variation in mass loss and changes in litter nitrogen were explained by characteristics of water‐vapor uptake by litter. Photodegradation induced by the intense solar radiation was an additional mechanism of litter decomposition as indicated by lignin dynamics. Lignin loss from litter increased with exposure to ultraviolet radiation and with initial lignin concentration, together explaining 90%–97% of the variation in lignin mass change. Our results indicate that water vapor, solar radiation and litter quality controlled decomposition and changes in litter chemistry during rainless seasons. Many regions worldwide experience transient periods without rainfall, and more land area is expected to undergo reductions in rainfall as a consequence of climate change. Therefore, absorption of water vapor might play a role in decomposition and nutrient cycling in an increasing number of ecosystems.
Changes in Inorganic and Organic Soil Phosphorus Fractions Induced by Cultivation Practices and by Laboratory Incubations1

Changes in inorganic and organic phosphorus (P) fractions resulting from 65 years of cropping in a wheat-wheat-fallow rotation were studied using a sequential extraction technique. Total P content of the cultivated soil was 29% lower than that of the adjacent permanent pasture; the major loss of P (74% of total P lost) was organic P and residual P. Of the total P lost, 22% was from the extractable organic P forms, whereas 52% originated from stable P.Incubation studies were used to study seasonal P transformations during simulated fallow with and without residue incorporation and P fertilization. Nine monthly additions of cellulose (765 µg C · g−1 soil) with and without P (9 µg · g−1 soil) significantly altered levels of total extractable organic P and inorganic P in incubated soils. Evidence is provided for microbial activity playing a major role in redistributing P into different forms in the soil
Characteristics of NEPE Propellant with Ammonium Dinitramide (ADN)

The theoretical performances of NEPE (nitrate ester plasticized polyether) propellant with and without ADN were calculated with minimum free energy method. The burning characteristics and the thermal decomposition of propellants were determined by nickel chromium wire method and TG- DTG, respectively. The SEM of NEPE propellants and the mechanical sensitivity were also detected. The results show that the specific impulse and the adiabatic flame temperature are increase with an increase in the content of ADN oxidizer. The burning rate and pressure exponent of propellant with a change of pat content of ADN can be boosted higher than those of the AP formulations.
The Influence of HVAC Systems on Indoor Secondary Organic Aerosol Formation

Chemical reactions between ozone and terpenoids can yield secondary organic aerosol (SOA), which are potentially a large source of indoor particles that are harmful to human health. The mass of SOA formed in a building is influenced by the operation of the heating, ventilation, and air-conditioning (HVAC) system. This investigation models the influence of HVAC systems on SOA concentrations in residential and commercial buildings. A parametric analysis explores the role of ventilation and recirculation rates, filtration efficiency and loading, and the operation of heat exchangers. In a rural setting, the median residential and commercial SOA concentrations for all simulations were 17.4 μg/m3 (1.09 × 10–9 lb/ft3), with a range of 2.47 to 27.0 μg/m3 (1.54 × 10–10 – 1.68 × 10–9 lb/ft3), and 10.6 μg/m3 (6.61 × 10–10 lb/ft3), with a range of 1.81 to 26.3 μg/m3 (1.13 × 10–10 – 1.64 × 10–9 lb/ft3), respectively. In an urban setting, the median predicted residential and commercial SOA concentrations were 68.0 μg/m3 (4.24 × 10–9 lb/ft3), with a range of 14.7 to 108 μg/m3 (9.17 × 10–10 – 6.74 × 10–9 lb/ft3), and 44.8 μg/m3 (2.80 × 10–9 lb/ft3), with a range of 11.6 to 105 μg/m3 (7.24 × 10–10 – 6.55 × 10–9 lb/ft3), respectively. The most influential HVAC parameters are the flow rates through the system, particle filtration efficiency, and indoor temperature for the residential and commercial models, as well as ozone removal on used filters for the commercial model. The results presented herein can be used to estimate the effects of altering HVAC system components and operation strategies on indoor SOA concentrations and subsequent exposure.
Synthesis of new acylhydrazones as iron-chelating compounds

Preparation de 42 acylhydrazones par condensation de 14 acylhydrazides avec pyridoxal, salicylaldehyde et hydroxy-2 naphtaldehyde-1. Complexation du fer; acceleration du mouvement du fer a travers les membranes biologiques
Effect of Different Inorganic Nanoparticles on Physical and Ultraviolet Aging Properties of Bitumen

The research reported in this paper evaluates a novel bitumen modification through the use of different inorganic nanoparticles, such as nanozinc oxide, nanosilica, and nanotitanium dioxide. In order to improve the dispersion of inorganic nanoparticles in bitumen, inorganic nanoparticles were surface-modified by 3-aminopropyltriethoxysilane. The effect of surface modified inorganic nanoparticles on physical and ultraviolet (UV) aging properties of bitumen was investigated. The UV aging mechanism of the inorganic-nanoparticle-modified bitumen was characterized by using Fourier-transform infrared spectroscopy (FTIR). The results show that 3-aminopropyltriethoxysilane is successfully bound on the surface of the three inorganic nanoparticles in the form of a covalent bond according to the FTIR result. Surface-modified inorganic nanoparticles show good compatibility with bitumen on the basis of high-temperature storage stability. Compared with nanosilica and nanotitanium dioxide, nanozinc oxide shows better dispersion in bitumen. The physical properties of bitumen are slightly influenced by the addition of inorganic nanoparticles. In addition, the changes of physical properties of bitumen depend on the nature of inorganic nanoparticles. The UV aging of bitumen is a process that causes bitumen to harden as indicated by FTIR, penetration, viscosity, and softening point values. However, the viscosity aging index and softening point increment of bitumen can be effectively reduced with the introduction of inorganic nanoparticles, indicating good UV aging resistance of inorganic-nanoparticle-modified bitumen. Three inorganic nanoparticles show different influence on the UV aging resistance of bitumen. Compared with nanosilica and nanotitanium dioxide, nanozinc oxide shows the better improvement in UV aging resistance of bitumen by displaying lower viscosity aging index and softening point increment values as well as the carbonyl index.
Studies on Semi‐technical Separation of Mung Bean Starch

Starch of mung beans is the raw material for high grade glass noodles, but until now industrial starch separation is often less efficient. For testing new fields of commercial use it is of benefit to experiment with very pure starches. Regarding this, possibilities of starch isolation on a semi-technical scale are described, which resulted in most pure starches. Crude protein content could be lowered down to 0.3% and crude fibre content down to 0.5% dry matter base.
Food safety in the Philippines: problems and solutions

This is a review of the challenges that are faced by the food safety control and regulatory systems in the Philippines. The components of the national Food Safety Network, namely agriculture and fisheries (fresh produce), the food industry (food manufacturing, distribution and retail outlets), the food service sector (restaurants, caterers, street vendors) and the consumers (household consumption) are described. The corresponding responsible regulatory agencies/bureaus and services and regulatory tools (laws) for each of the components are characterised. The national food safety strategy is being implemented by several government agencies and bureaus and is therefore highly fragmented with plenty of overlap and gaps. This has resulted in more often reactive rather than pre-emptive government response to food borne illness outbreaks and recalls of substandard quality products in the market. A firm declaration of national policy on food safety and the creation of a single authority mandated with a focused i.
Physiological and Biochemical Responses of Ontario Slimy Sculpin (Cottus cognatus) to Sediment from the Athabasca Oil Sands Area

This study was conducted to evaluate whether a laboratory exposure of reference fish to oil sands sediment could produce biochemical responses (increases in 7-ethoxyresorufin-O-deethylase [EROD] activity and decreases in vitro steroid production capacity) similar to fish caught in the Athabasca Oil Sands area. Sediment samples from the Steepbank River, Alberta, were collected outside of the oil sands area at a reference site (S-Ref), within the oil sands areas where oil sand compounds leach naturally into the surface water (S-Nat), and within the natural-leach deposit areas, but also adjacent to anthropogenic mining activity (S-Dev). In the laboratory, an Ontario reference population of slimy sculpin (Cottus cognatus) were exposed to sediment concentrations of 10 or 20 g/L, for 4 and 8 d. A period of 4 d was sufficient to induce EROD activity in this species by these sediments. The EROD activity measured in exposed fish was comparable to that measured in fish native to the oil sands area. This study was not capable of predicting a reduced ability of gonadal tissue of exposed fish to produce steroid hormones in vitro, as was demonstrated in the wild fish assessment of 1999 and 2000. The short-term laboratory bioassay exposing slimy sculpin to sediment from the Athabasca Oil Sands area was not a suitable surrogate for field studies, however it could be an important tool in identifying MFO-inducing compounds in Athabasca Oil Sands sediment using a Toxicity Identification Evaluation (TIE).
Toward high-performance solution-processed carbon nanotube network transistors by removing nanotube bundles

Reported solution-processed field-effect transistor (FET) devices based on single-walled carbon nanotube (SWNT) networks have either high mobility but low on/off ratio or vice versa. Recently, Arnold et al. (Nat. Nanotechnol. 2006, 1, 60−65) have made significant improvements in obtaining semiconductor-enriched SWNTs by using density-gradient ultracentrifugation. Here, we report that removing the SWNT bundles using organic−aqueous interfacial purification can further enhance the electrical performance of SWNT-FETs. The on/off ratio of the SWNT-FET is improved by ∼1 order of magnitude. By combining density-gradient ultracentrifugation and interfacial purification, it is possible to obtain high on/off ratio and high mobility of solution-processed SWNT-FETs at a promising yield.
Qualidade de frutos de cajá-manga armazenados sob diferentes temperaturas

This study aimed to determine the effect of different storage temperatures on fruit quality of ambarella. The ambarella fruits were obtained from the Company CEAGESP-General Warehouses of Sao Paulo and transported in cool boxes to the laboratory, where they were selected for their appearance, maturity and lack of physical damage, then sanitized in 50 ppm chlorine-free solution and packaged in polystyrene trays wrapped with film of polyvinyl chloride (PVC). The experiment was a completely randomized design with three treatments (4, 8 and 25 oC) and 5 times interval (0, 3, 6, 9 and 12 days after the experiment installation). In each survey, firmness, titratable acidity, soluble solids, ascorbic acid content and the skin color were evaluated, as well as the release of CO2 by the fruit over time. It was observed that low temperatures prolong the shelf life of fruits and the storage temperature influences the characteristics, and the temperature of 8 oC was the most suitable for the storage of ambarella fruits.
Intermolecular interactions in ternary system of 2-dimethylaminoethanol + methanol + ethanol at various temperatures: ultrasonic, volumetric and IR study

Ultrasonic velocities () and densities () of the ternary mixture of 2-dimethylaminoethanol (DMAE) with methanol (Me-OH) and ethanol (Et-OH), including those of pure liquids, over the entire composition range were measured at temperatures 298.15, 308.15 and 318.15 K. From the experimental values of ultrasonic velocity and density, the adiabatic compressibility (), intermolecular free length (), molar sound velocity (), molar compressibility () and specific acoustic impedance () were calculated. The excess values of ultrasonic velocity (), adiabatic compressibility (), intermolecular free length (), acoustic impedance () and molar volume () were also calculated. The IR spectra of DMAE + Me-OH + Et-OH system have also been recorded at room temperature (298.15 K) and found to be very helpful for understanding the occurrence of intermolecular hydrogen bonding between the components of ternary liquid mixture.
Newtonian Airless Liquid Jet Interaction with a High Speed Moving Surface

In the railroad industry a friction modifying agent may be applied to the track in the form of a liqui d jet. In this mode of application the interaction between the hig h speed liquid jet and a fast moving surface is imp ortant. Seven different Newtonian liquids with widely varyi ng shear viscosities were tested to isolate the eff ect of viscosity from other fluid properties. Tests were also done with five surfaces having different roughness heights to investigate the effects of surface roughness. High speed video imaging was employed to scrutinize the interaction between the impacting jet and the moving surfa ce. For all surfaces decreasing the Reynolds number reduced the incidence of splash and consequently enhanced t he transfer efficiency. The Weber number had a smaller impact on splash than did the Reynolds number. The ra tio of the surface velocity to the jet velocity has only a small effect on the splash, whereas increasing the roughn ess height/jet diameter ratio substantially decreas ed the splash threshold.
Simultaneous determination of neutral, anionic and cationic compounds within one chromatographic run using an inductively coupled plasma mass spectrometer as element-specific detector

Two simple methods fear the simultaneous separation of anionic and cationic arsenic species in a single injection were developed. One method was a dual column system connected with anion and cation exchange columns; the other was a dual mode system. The dual mode system was a combination of ion exclusion and cation exchange modes. The cation exchange resin, functionalized by dicarboxylic acid, was used for the dual mode column. Separation conditions for the two separation methods were optimized for eight arsenic species. The eight arsenic standards were completely separated within 40 min in both methods. On the dual column system, a good reproducibility (peak area reproducibility was 5% and under) for arsenic species was obtained by applying the column switching method, although the retentions of anionic arsenic species did fluctuate by interference of strong adsorptive anions. Inductively coupled plasma mass spectrometry as an element-selective detector was used. Detection limits for the eight arsenic compounds ranged from 0.1 to 0. 7μgAsdm -3 , and reproducibility (relative standard deviation, n = 8) ranged from 2.4 to 8.0% at 0.01 mg As dm -3 . The simultaneous separation methods developed were applied to the determination of arsenic species in human and rat urine. Good agreement on the quantified values by the two separation methods was obtained for all arsenic species in the urine samples.
Further flavonol glycosides of Embelia schimperi leaves

Fractionation of the methanolic extract of Embelia schimperi leaves has led to the isolation of two novel flavonol glycosides. The compounds were characterized as isorhamnetin 3- O - b -galactoysyl (1 ® 4)- b -galactoside and quercetin 3- O -[ a -rhamnosyl (1 ® 2)] [ a -rhamnosyl (1 ® 4)]- a -rhamnoside. Also reported from the same extracts were known compounds quercetin, myricetin, quercetin 3- O - a -rhamnoside, quercetin 3- O - b -glucoside, quercetin 3- O -rutinoside, myricetin 3- O - b -xyloside, isorhamentin 3- O - b -glucoside and myricetin 3- O - b -glucoside. Their structural elucidation was accomplished using spectral measurements and chemical methods. KEY WORDS: Embelia schimperi , Flavonol glycosides, Isorhamnetin 3- O - b -galactoysyl (1 ® 4)- b galactoside, Quercetin 3- O -[ a -rhamnosyl (1 ® 2)] [ a -rhamnosyl (1 ® 4)]- a -rhamnoside Bull. Chem. Soc. Ethiop. 2004 , 18(1), 51-57.
Relation of certain infrared bands to cellulose crystallinity and crystal lattice type. Part II. A new infrared ratio for estimation of crystallinity in celluloses I and II

A new infrared ratio, α1372 cm. −1/α2900 cm. −1, is proposed for measuring crystallinity in cellulosic materials. The advantage of this ratio over others which have been used is that it can be applied to both celluloses I and II and, therefore, to samples containing a mixed lattice. Two series of samples, encompassing a wide range of crystallinity, were prepared from highly crystalline celluloses I and II. The infrared ratios of these samples were compared with crystallinity values from x-ray diffractograms and density measurements, and with accessibility data from moisture sorption. It was shown that the new infrared ratio ranks samples of both lattice types, as well as partly mercerized cottons, in the same order as do x-ray, density, and moisture sorption data. The correlation of the new infrared ratio with accessibility, derived from moisture regain, is better than with crystallinities from either x-ray or density measurements. Reasons for this are suggested.
Degradation of Gymnosperm (Guaiacyl) vs. Angiosperm (Syringyl/Guaiacyl) Lignins by Phanerochaete chrysosporium

This study examined the relative degradabilities of guaiacyl and syringyl/guaiacyl lignins by the white-rot fungus Phanerochaete chrysosporium Burds. Synthetic syringyl/guaiacyl lignin (Cpin syringyl units) was depolymerized much more rapidly than synthetic guaiacyl lignin (Cp), although the two were oxidized to CO2 at the same rate. Milled wood lignin or birch, labeled with H at Ce, was also depolymerized more rapidly than similarly labeled spruce milled wood lignin. During degradation two to three times äs much of both the synthetic and natural guaiacyl lignins became mycelium-bound äs the syringyl/guaiacyl lignins. This result is interpreted to reflect a greater resistance of the guaiacyl lignins. Collectively, our results point to a more facile initial degradation of the syringyl/guaiacyl type of lignins. This finding helps explain the more rapid degradation of angiosperm wood than gymnosperm wood by white-rot fungi.
Studies on Anaerobic Digestion Mechanism: Influence of Pretreatment Temperature on Biodegradation of Waste Activated Sludge

The effect of thermal pretreatment on hydrolysis, acidogenesis and methanogenesis during anaerobic digestion of waste activated sludge (WAS) was investigated. Pretreatment temperature of WAS ranged from 60°C to 120°C and the holding times were 5, 10, 20, 30 and 60 minutes. WAS was fed into the laboratory-scale anaerobic digesters, after thermal pretreatment. The preliminary conversion step (such as death/lysis of cell and hydrolysis of WAS) was promoted through thermal pretreatment, and consequently efficiencies of acidogenic and methanogenic steps were also markedly enhanced. Thermal pretreatment at lower temperature resulted in a significant increase in methane generation and destruction of organic matter. At 60°C, when hydraulic retention time (HRT) was 8 days, an increase in approximately 52.1 % in methane generation (ml. l−1. d−1) and 26.6% in organic matter destruction was achieved (Series-I). In addition, HRT necessary for anaerobic digestion could be reduced by thermal pretreatment.
Physicochemical Properties of Protoporphyrin IX by Metal Ions in Acetonitrile-Water Mixture Solution

Porphyrin derivatives contain pyrrole rings, five membered heterocycles. These compounds have properties of a conjugated diene and of an amine. Delocalization of π electrons stabilizes the ring and their ultra-violet absorption maximum peak shifts to a longer wavelength. They can easily absorb visible light, and thus can utilize sunlight directly as a good photosensitizer. Re-cently, photodynamic therapy has been used in the management of various malignant tumors, including cancers of the skin, gas-trointestinal tract, lung and uterus.