Distillery waste recycle through membrane filtration in batch alcohol fermentation

A ceramic ultrafiltration membrane was used to recycle distillery wastes in a batch ethanol fermentation process. By reusing the membrane permeate in the saccharification step, almost the same ethanol yield was obtained up to eight recycles and a slight increase in the fermentation by-products was observed. As the number of recycles increased, organic compounds and salts accumulated up to the third recycle but leveled off afterward.     

Identification of a dedicated recycling pathway for anhydro-N-acetylmuramic acid and N-acetylglucosamine derived from Escherichia coli cell wall murein

Turnover and recycling of the cell wall murein represent a major metabolic pathway of Escherichia coli. It is known that E. coli efficiently reuses, i.e., recycles, its murein tripeptide, L-alanyl-gamma-D-glutamyl-meso-diaminopimelate, to form new murein. However, the question of whether the cells also recycle the amino sugar moieties of cell wall murein has remained unanswered. It is demonstrated here that E. coli recycles the N-acetylglucosamine present in cell wall murein degradation products for de novo murein and lipopolysaccharide synthesis. Furthermore, E. coli also recycles the anhydro-N-acetylmuramic acid moiety by first converting it into N-acetylglucosamine. Based on the results obtained by studying mutants unable to recycle amino sugars, the pathway for recycling is revealed.     

An odometre for underwater transects

A simple device for the measurement of length (or area) along an underwater transect is described. This instrument is pushed or pulled by SCUBA divers along lake or river bottoms and the rotation of a paddle wheel is recorded on a digital counter. The device eliminates the need for straight line and smooth bottom transects, and allows for greater versatility than that provided by the more usual rope line transect.     

Spike trains and kinase II for a digital model of long term memory (An exercise in evolutionary constraints)

Memory is the repetition of an even and this requires re-firing a sufficient number of neurons that did participate to the event. We assume that an event is identified by a digital code sealed into a molecular counter, kinase II, capable of taking billions of configurations. We also assume that spike trains represent numbers in binary notation that are able to code and decode kinase II. Coding means that a number is imprinted by setting kinase II in a certain configuration, decoding means activating kinase II carrying that number in order to liberate Ca2+ via Calmodulin and open the various segments of circuit where it is located. We assume that coded kinase II is stored in dendritic spines, adjacent to synapses, that protect in from metabolic destruction of the coding. The model easily interprets the fact that the same optical or olfactory stimuli will induce identical spike trains. Because identification requires the re-opening of a specific memory. So the smell of a rose must open the circuit of the rosesmell via the appropriate spike train.     

An on-line realtime cardiotachograph]

A realtime cardiotachogram was devised to detect fluctuation of cardiac rhythm. The apparatus is composed of five parts; (1) a "preamplifier" for recording electrical and/or mechanical cardiac activities, (2) a "slicer" to obtain sampling pulses from cardiac activity at a certain trigger level, (3) a "trigger pulse generator" to monitor sampling pulse, (4) an "oscillator" whose output is fed to a pulse counter, and (5) a "pulse counter" which counts the outputs of the oscillator during the gating period determined by the sampling pulses. The count numbers are converted to analog output, thus we can get sawtooth wave whose amplitude is directly proportional to the cardiac interval. The cardiac intervals between 100 ms and 5 seconds can be recorded by this tachograph.     

Immobilization of steapsin lipase on macroporous immobead-350 for biodiesel production in solvent free system

Commercially available steapsin lipase was immobilized on macroporous polymer beads (IB-350) and further investigated for biodiesel production under solvent free conditions. The fatty acid methyl ester (biodiesel) synthesis was carried out by the methanolysis of fresh and used cooking sunflower oil. The enzymatic reaction for biodiesel synthesis was optimized with various reaction parameters and the obtained reaction conditions were 1: 6 molar ratio (oil: methanol), 50 mg biocatalyst and 20% water content at 45°C for 48 h under solvent free conditions. It was observed that 94% of biodiesel was produced under the optimized reaction conditions. The four step addition of methanol at the interval of 12 h was found to be more effective. Moreover the biocatalyst was effectively reused for four consecutive recycles and was appreciably stable for 90 days. The results obtained highlight potential of immobilized steapsin lipase for biodiesel production.     

Counter Current Line Absorption Immunoelectrophoresis is an Alternative Diagnostic Screening Test to Counter Current Immunoelectrophoresis in Aleutian Disease (AD) Eradication Programs

Counter current immunoelectrophoresis (CCIE) is the diagnostic method used in the ongoing Aleutian disease virus eradication program on Danish mink farms. There has been an increasing demand for an alternative diagnostic test especially to evaluate suspected false positive CCIE reactions. We compared test results of a number of negative and positive mink sera in indirect counter current immunoelectrophoresis (ICCIE), counter current line absorption immunoelectrophoresis (CCLAIE) and radio immuno assay (RIA) with test results from counter current immunoelectrophoresis and found that counter current line absorption immunoelectrophoresis is the best alternative diagnostic screening test to counter current immunoelectrophoresis for Aleutian disease eradication programs. Not only proved the CCLAIE test to be useful for evaluation of doubtfully positive CCIE reactions, but it was found to have a higher sensitivity than the CCIE test.     

Mathematical analysis of copy number variation in a DNA sample using digital PCR on a nanofluidic device

Copy Number Variations (CNVs) of regions of the human genome have been associated with multiple diseases. We present an algorithm which is mathematically sound and computationally efficient to accurately analyze CNV in a DNA sample utilizing a nanofluidic device, known as the digital array. This numerical algorithm is utilized to compute copy number variation and the associated statistical confidence interval and is based on results from probability theory and statistics. We also provide formulas which can be used as close approximations.     

Simultaneous measurement of fluorescence and phosphorescence using synchronously gated photon counters.

The fluorescence (prompt emission) and phosphorescence (delayed emission) from a sample can be separated and recorded simultaneously by digital processing of the photon-induced electronic pulses they generate. A single rotating sector wheel (or “chopper”) periodically interrupts the beam of radiation incident upon the sample. Both prompt and delayed emissions from the sample pass through the same optical system to a photomultiplier. The electronic pulses they generate are processed by the same amplifiers and discriminator. Separation of the prompt and delayed components is a two-stage process. Pulses produced while the chopper is blocking the exciting beam are stored in one counter, the contents of which are a measure of the delayed emission. Pulses produced while the chopper is open are stored in another counter. The contents of this counter represent contributions of both prompt and delayed emissions. The contents of both counters are transferred to a computer for postexperimental deconvolution of the fluorescence and phosphorescence. Since the two components are measured simultaneously, the ratio of phosphorescence to fluorescence cannot be affected by changes in the sample as with sequential scans. The optical path, electronic amplification, and gating periods are identical so fluorescence and phosphorescence are measured with equal efficiency. This two-step method of signal processing recovers data which are lost in other arrangements.     

Upstream migration of adult Atlantic salmon past a fish counter weir in the Aberdeenshire Dee, Scotland

During their upstream migration through the lower reaches of the Aberdeenshire Dee, Scotland, radio-tagged adult Atlantic salmon passed a Crump weir-based fish counter without substantial delay over a range of river flows and water temperatures. Tagged salmon were detected sequentially by automatic listening stations placed along the river and were detected at the counter site for a median time of 18 min, compared with a median time of 5 min before the weir was built. One fish out of 16 spent 6·7 h in the vicinity of the weir, but such migratory pauses also occurred before the weir existed. The results suggest that the number of salmon crossing the counter per unit time is a function of the number of fish present downstream and their tendency to migrate upstream, without being limited by their ability to surmount the weir. The apparent slight delay at the weir is probably insignificant in terms of the overall progress of riverine migration and in the context of using counter records to relate salmon movements to environmental Variables.     

结冷胶固定化保加利亚乳杆菌及在玉米秸秆连续发酵d-乳酸中的应用

秸秆生物炼制化学品是解决秸秆资源利用附加值低、减轻秸秆焚烧带来的环境污染的主要方法之一。本研究制备了结冷胶固定化保加利亚乳酸杆菌(Lactobacillus bulgaricus)T15凝胶珠(结冷胶-T15凝胶珠),并对其性质进行表征,建立了结冷胶-T15凝胶珠固定化细胞循环连续发酵产D-乳酸发酵工艺。结冷胶-T15凝胶珠的断裂应力为(91.68±0.11) kPa,较海藻酸钙固定化T15凝胶珠(海藻酸钙-T15凝胶珠)提高了125.12%,表明结冷胶-T15凝胶珠的强度更强。以结冷胶-T15凝胶珠为出发菌株,葡萄糖为发酵基质,10批次循环(720h)发酵,其D-乳酸最高批次产量为(72.90±2.79)g/L,较海藻酸钙-T15凝胶珠提高了33.85%,较游离T15提高了37.70%。将葡萄糖更换为玉米秸秆酶解液,使用结冷胶-T15凝胶珠进行10批次循环(240 h)发酵,D-乳酸生产强度可达(1.74±0.79)g/(L·h),远高于游离菌。10批次循环发酵后结冷胶-T15凝胶珠磨损率小于5%,表明结冷胶是一种细胞固定化的良好载体,可广泛应用于细胞固定化工业发酵领域。本研究为细胞...     

An Inhibitory Role of the G-Protein Regulator AGS3 in mTOR-Dependent Macroautophagy

Macroautophagy is a cellular process whereby the cell sequesters and recycles cytosolic constituents in a lysosome-dependent manner. It has also been implicated in a number of disorders, including cancer and neurodegeneration. Although a previous report that AGS3 over-expression promotes macroautophagy suggests a stimulatory role of AGS3 in this process, we have found that knock-down of AGS3, unexpectedly, also induces macroautophagy, indicating an inhibitory function of endogenous AGS3 in macroautophagy. Interestingly, AGS3 phosphorylation is decreased upon induction of mammalian target of rapamycin (mTOR)-dependent macroautophagy. Moreover, unlike wild-type AGS3, over-expression of an AGS3 mutant lacking this modification fails to enhance macroautophagic activity. These observations imply that AGS3 phosphorylation may participate in the modulation of macroautophagy.     

Application of an automated colony counter for evaluation of the viability of a yeast culture

Application of an automated colony counter for evaluation of the viability of microbial cultures was investigated with yeast cultures as a model. Statistical comparison of the results of automated and visual (“manual”) colony counting is presented, as well as the results of the application of the bundled software to digital images obtained by light microscopy for determination of the cell concentration in suspensions. Automated counting is concluded to significantly accelerate the evaluation of culture viability by colony-forming capacity, provided that a certain requirements of sample preparation and analysis are observed.     

Mechanisms of mitochondria and autophagy crosstalk

Autophagy is a cellular survival pathway that recycles intracellular components to compensate for nutrient depletion and ensures the appropriate degradation of organelles. Mitochondrial number and health are regulated by mitophagy, a process by which excessive or damaged mitochondria are subjected to autophagic degradation. Autophagy is thus a key determinant for mitochondrial health and proper cell function. Mitophagic malfunction has been recently proposed to contribute to progressive neuronal loss in Parkinson's disease. In addition to autophagy's significance in mitochondrial integrity, several lines of evidence suggest that mitochondria can also substantially influence the autophagic process. The mitochondria's ability to influence and be influenced by autophagy places both elements (mitochondria and autophagy) in a unique position where defects in one or the other system could increase the risk to various metabolic and autophagic related diseases.     

Schedule discrimination in a mixed schedule: implications for models of the variable-ratio, variable-interval rate difference

In Experiment 1, each of three humans knowledgeable about operant schedules used mouse clicks to respond to a "work key" presented on a monitor. On a random half of the presentations, work-key responses that completed a variable ratio (VR) 12 produced a tone. After five tones, the work key was replaced by two report keys. Pressing the right or left report key, respectively, added or subtracted yen50 from a counter and produced the work key. On the other half of the presentations, a variable interval (VI) associated with the work key was defined so its interreinforcer intervals approximated the time it took to complete the variable ratio. After five tone-producing completions of this schedule, the report keys were presented. Left or right report-key presses, respectively, added or subtracted yen50 from the counter. Subjects achieved high yen totals. In Experiment 2, the procedure was changed by requiring an interresponse time after completion of the variable interval that approximated the duration of the reinforced interresponse time on the variable ratio. Prior to beginning, subjects were shown how a sequence of response bouts and pauses could be used to predict schedule type. Subjects again achieved high levels of accuracy. These results show humans can discriminate ratio from interval schedules even when those schedules provide the same rate of reinforcement and reinforced interresponse times.     

Complete genome sequence of the complex carbohydrate-degrading marine bacterium, Saccharophagus degradans strain 2-40 T

The marine bacterium Saccharophagus degradans strain 2-40 (Sde 2-40) is emerging as a vanguard of a recently discovered group of marine and estuarine bacteria that recycles complex polysaccharides. We report its complete genome sequence, analysis of which identifies an unusually large number of enzymes that degrade >10 complex polysaccharides. Not only is this an extraordinary range of catabolic capability, many of the enzymes exhibit unusual architecture including novel combinations of catalytic and substrate-binding modules. We hypothesize that many of these features are adaptations that facilitate depolymerization of complex polysaccharides in the marine environment. This is the first sequenced genome of a marine bacterium that can degrade plant cell walls, an important component of the carbon cycle that is not well-characterized in the marine environment.     

Temporal generalization accounts for response resurgence in the peak procedure

The peak interval (PI) procedure is commonly used to evaluate animals' ability to produce timed intervals. It consists of presenting fixed interval (FI) schedules in which some of the trials are replaced by extended non-reinforced trials. Responding will often resume (resurge) at the end of the non-reinforced trials unless precautions are taken to prevent it. Response resurgence was replicated in rats and pigeons. Variation of the durations of the FI and the non-reinforced probe trials showed it to be dependent on the time when reinforcement is expected. Timing of both the normal time to reinforcement, and the subsequent time to reinforcement during the probe trials followed Weber's law. A quantitative model of resurgence is described, suggesting how animals respond to the signaling properties of reinforcement omission. Model results were simulated using a stochastic binary counter.     

IgG transcytosis and recycling by FcRn expressed in MDCK cells reveals ligand-induced redistribution

The neonatal Fc receptor (FcRn) transports IgG across epithelial cells and recycles serum IgG. FcRn binds IgG at the acidic pH of endosomes and releases IgG at the basic pH of blood. We expressed rat FcRn in polarized MDCK cells and demonstrated that it functions in transcytosis and recycling of IgG. In the absence of IgG, FcRn is distributed predominantly apically, but redistributes to basolateral locations upon IgG addition, indicating that ligand binding induces a signal that stimulates transcytosis. FcRn transcytoses IgG more efficiently in the apical to basolateral than the reverse direction when IgG is internalized by receptor-mediated endocytosis at acidic pH or by fluid phase endocytosis at basic pH. The PI 3-kinase inhibitor wortmannin disrupts basolateral recycling and transcytosis in both directions, but only minimally reduces apical recycling. Confocal imaging and quantitative IgG transport studies demonstrate that apically-internalized IgG recycles to the apical surface mainly from wortmannin-insensitive apical early endosomes, whereas FcRn-IgG complexes that transcytose to the basolateral surface pass through downstream Rab11-positive apical recycling endosomes and transferrin-positive common endosomal compartments.     

Interval cancers as related to frequency of recall to assessment in the South Australian population-based breast screening program: An exploratory study

Australian accreditation standards specify upper limits for percentages of women recalled for further assessment following screening mammography. These limits have been unchanged since national screening commenced circa 1990, although screening target ages have changed, and technology from analogue to digital mammography. This study compared 2804 women with interval cancers diagnosed since national screening began (cases) with 14,020 cancer-free controls (5 controls per case), randomly selected after matching by age, round, screen type and calendar year of screening episode, to determine the odds of interval cancer by differences in clinic recall to assessment percentages. Within low numbers of recalls that were within accepted accreditation ranges, results did not indicate more frequent recalls to assessment to be associated with fewer interval cancers in the analogue era. However, more frequent recalls were associated with reduced interval cancers for digital screens. These results are not conclusive, requiring confirmation in other screening environments, especially those with larger numbers of digital screens. If confirmed, frequency of recalls to assessment may need adjustment to get the best trade-offs in the digital era between reduced odds of interval cancers from more recalls and increases in financial and non-financial costs, including increased potential for overdiagnosis.     

Roles of O-acetyl-L-homoserine sulfhydrylases in micro-organisms

O-Acetyl-L-homoserine sulfhydrylase (EC 4.2.99.10) is essential for certain micro-organisms, functioning as a homocysteine synthase in the pathway of methionine synthesis. It participates in an alternative pathway of L-homocysteine synthesis for those microbes in which homocysteine is synthesized mainly via cystathionine. The protein can also catalyze the de novo synthesis of L-cysteine and O-alkyl-L-homoserine in some microorganisms. The enzyme possibly recycles the methylthio group of methionine.