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Interaction of β2-glycoprotein I (β2GPI) with anionic membranes is crucial in antiphospholipid syndrome (APS), implicating the role of its membrane-binding domain, domain V (DV). The mechanism of DV binding to anionic lipids is not fully understood.

Byline: Hale, S. Following these procedures will improve measurement accuracy and reliability The nature of liquefied natural gas (LNG) raises many challenges when it comes to the measurement and reporting [...]

An electronic nose (e-nose), containing 16 tin metal oxide sensors with various sensitivities, was used to classify decay times in an 18 h accelerated decay study of tilapia (Oreochromis niloticus). Data collected were split into three 6 h base classes for training. Principal component analysis was tested for feature extraction to be used in classification but was found to be inadequate. Linear discriminate analysis was also used and found adequate for feature extraction. Both least squares and K-nearest neighbor classifiers were explored. Least squares and K-nearest neighbor produced classification rates of 86.4% and 87.0%, respectively. Data combing techniques were used to increase classification rates from 87.0% to 97.8% for K-nearest neighbor. Optimum classification performance was achieved with classes corresponding to 0-1.9 h, 6-7.9 h, and 12-13.9 h. The dataset was also classified into six 3 h classes. Data classifications for the 3 h classes followed trends expected for decaying freshwater fish. Data combing was again employed to increase the classification that was possible. A final classification was achieved of 78.8% for least squares and 83.8% for K-nearest neighbor. [ABSTRACT FROM AUTHOR]

A persistent lactation is dependent on maintaining the number and activity of milk secreting cells with advancing lactation. When dairy cows are milked twice daily, the increase in milk yield from parturition to peak lactation is due to increased secretory activity per cell rather than to accretion of additional epithelial cells. After peak lactation, declining milk yield is due to loss of mammary epithelial cells by apoptosis. During lactation, only 0.3% of mammary cells proliferate in a 24-h period. Yet this proliferative rate is sufficient to replace most mammary epithelial cells by the end of lactation. Management practices can influence lactation persistency. Administration of bovine somatotropin may enhance persistency by increasing cell proliferation and turnover, or by reducing the rate of apoptosis. Increased photoperiod may also increase persistency of lactation by mechanisms that are as yet undefined. Increased milking frequency during the first weeks of lactation increases milk yield, even after return to less frequent milking, with increases of approximately 8% over the entire lactation. A mammary cell proliferation response to frequent milking during early lactation appears to be involved. Conversely, advanced pregnancy, infrequent milking, and mastitis increase death of epithelial cells by apoptosis. Regulation of mammary cell renewal provides a key to increasing persistency. Investigations to characterize epithelial cells that serve as the proliferative population in the bovine mammary gland have been initiated. Epithelial cells that stain lightly in histological sections are evident through all phases of mammary development and secretion and account for nearly all proliferation in the prepubertal gland. Characterization of these cells may provide a means to regulate mammary cell proliferation and thus to enhance persistency, reduce the effects of mastitis, and decrease the necessity for a dry period.

Mass loss of precooked tuna muscle during retorting and storage in cans impacts cannery yield and throughput. Changes in moisture content and mass of frozen, thawed, precooked tuna muscle chunks, canned in water, were determined after retorting and through five weeks of subsequent storage. Canned tuna pieces were retorted to equivalent lethality (Fo‐value of four) for different time and temperature processes. Retorting at a lower temperature, longer time resulted in less mass loss than higher temperature, shorter time processes. Canned storage of up to five weeks had no effect on muscle mass or moisture content.

Assessing source text difficulty for the purpose of translation is of utmost importance in selecting texts for translator training and examination. However, very few guidelines exist on how to select texts according to level of difficulty and little empirical research has been carried out in this area to inform educators and translation accreditation bodies. This paper presents the results of a data based study on English source text difficulty when translated into Arabic and Spanish by students of the University of Western Sydney, Australia.The paper extends on the results presented in Campbell & Hale (1999) and attempts to answer the following questions: 1. What kinds of lexical items and syntactic structures appear to cause most difficulty to translate according to the different alternative renditions produced by the subjects? 2. Is there a correlation between the number of choices available to the translator and the level of accuracy of translation? and, 3. If there is not a perfect correlation in (2), what implications are there for our understanding of the notion of translation difficulty?RésuméL'valuation de la difficulté d'un texte source dans le but de le traduire relève de la plus grande importance lors du choix des textes destinés à la formation et aux examens de traducteurs. Cependant, il existe très peu de directives sur la façon de déterminer les textes selon leur niveau de difficulté et très peu de recherches empiriques ont étés menées dans ce domaine pour informer les enseignants et les organismes d ágréation en traduction.Cet article présente les résultats d'une étude basée sur des données à propos des difficultés d'un texte source en langue anglaise lorsqu'il est traduit vers les langues arabe et espagnole per des étudiants de la 'University of Western Sydney' Australie.L'article développe les résultats présentées dans Campbell & Hale (1999) et tente de répondre aux questions suivantes: 1.- Quels types d'lements lexicaux et de structure syntactique semblent causer le plus de difficultés à traduire selon les diverses traductions alternatives proposées par les étudiants? 2.- Existe-t-il une corrélation entre le nombre de choix à la disposition du traducteur et le degré d'exactitude de la traduction, et, 3.- S'il n'existe pas une corrélation parfaite au point 2, quelles sont les implications pour notre compréhension de la notion de difficulté en traduction?

The following article aims to explore how slow stream mental health rehabilitation can be provided, first through a working model that allows occupational therapy and mental health nursing to work together more collaboratively and, second, how a hostel environment can be used to increase the functional independence of people with enduring mental health problems.

Growth of two Cattleya clones (Sophrolaeliocattleya Jewel Box 'Scheherezade' and Brassolaeliocattleya Rugley's Mill 'Mendenhall') over 6 or 8 months on microporous polypropylene membrane rafts was compared for several inorganic nutrient formulations: Murashige and Skoog at full, half and quarter strength; Hoagland's hydroponic medium; and three media formulated specifically for orchid culture (Knudson, Lindemann, and Vacin and Went). Greatest fresh weight and number of plants per vessel were obtained on Murashige and Skoog medium and dilutions thereof. Shoot growth was greater than root growth only on full strength MS media. Media uptake by tissue and evaporation from the vessels required additional water to maintain contact between membrane and liquid. Most rapid growth occurred in periods following addition of water. In more dilute media formulations, shifting growth from shoots to roots was a possible outcome of low concentrations of ammonium.

A flavin-containing monooxygenase has been purified to apparent homogeneity from lung microsomes of pregnant rabbits and characterized with respect to a number of physical and catalytic parameters. The apparent molecular weight, as determined on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was 59,000, and the lung microsomal flavoprotein was shown to contain 14 nmol of FAD/mg of protein. Addition of NADP+ to the oxidized flavoprotein produced a shift in the spectrum characteristic of the flavin-containing monooxygenase from porcine liver, and addition of small amounts of NADPH to the oxidized rabbit lung enzyme produced a stable spectral intermediate consistent with that of a 4a-peroxyflavin. Rabbit lung flavin-containing monooxygenase differed markedly from the porcine liver enzyme in exhibiting a broader pH optimum from 8.5-10.5, by not being inhibited by concentrations of sodium cholate as high as 1% and by withstanding, in the absence of NADPH, incubation at 45 degrees for at least 10 min with no significant loss of activity. Unlike the pig liver enzyme, purified rabbit lung enzyme was not activated by n-octylamine and, in fact, n-octylamine stimulated NADPH oxidation. A number of compounds known to be substrates of the pig liver enzyme, including benzphetamine, chlorpromazine, and imipramine, are not substrates for the rabbit lung enzyme, whereas prochlorperazine and trifluoperazine are excellent substrates. Antibodies to rabbit lung flavin-containing monooxygenase were raised in guinea pig and utilized for the immunoquantitation of this enzyme throughout gestation. The activity (as determined by N,N-dimethylaniline-N-oxidation) and amount of rabbit lung flavin-containing monooxygenase were maximally induced (5-fold) on the 28th day of gestation. Liver microsomes from rabbit did not contain any of the lung form of flavin-containing monooxygenase at any time during gestation, as evidenced by results from Western blotting. These results demonstrate that, at least in rabbit, flavin-containing monooxygenase can exist as more than a single form. The physiological significance of the induction of this enzyme during pregnancy is not known.

A plant micropropagation system has been developed with the capacity of allowing periodic, automatic, aseptic monitoring of culture medium composition. The system was able to sample automatically culture medium from a liquid/membrane bioreactor without compromising asepsis or disturbing plant tissue. Media samples were analyzed to determine sucrose and dextrose concentrations. Bioreactor media was automatically replenished to compensate for volumes lost due to sampling. For a 28-day culture period using Stage 1 Nicotiana tabacum (tobacco) explants as a model culture system, media sucrose concentration decreased with a corresponding increase in dextrose concentration and tissue fresh weight.

The absolute quantum yields for exciplex fluorescence in four solutions which have potential as exciplex-based vapor/liquid visualization systems have been measured. The room-temperature absolute quantum yields for 10% dibutyl-aniline/0.4%, 1-cyanonaphthalene, 12.5% 1-methyl-naphthalene/0.5% N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD), 10% trihexylamine/1.0% 1-cyanonaphthalene, and 10% naphthalene/1.0% TMPD in hexadecane or cyclohexane are 0.03 ± 0.005, 0.05 ± 0.002 (308 nm), 0.02 ± 0.001, and 0.16 ± 0.021, respectively. The temperature dependence of the absolute quantum yield for the 10% naphthalene/1% TMPD in the hexadecane system was measured over the range of 23 to 260°C and was found to decrease by 20–30% at 260°C.

Cytochrome P-450-dependent prostaglandin omega-hydroxylation is induced over 100-fold during late gestation in rabbit pulmonary microsomes (Powell, W.S. (1978) J. Biol. Chem. 253, 6711-6716). Purification of cytochromes P-450 from lung microsomes of pregnant rabbits yielded three fractions. Two of these fractions correspond to rabbit lung P-450I (LM2) and P-450II (LM5), which together constitute 70-97% of total cytochrome P-450 in lung microsomes from nonpregnant rabbits. The third form, which we designate rabbit cytochrome P-450PG-omega, regioselectively hydroxylates prostaglandins at the omega-position in reconstituted systems with a turnover of 1-5 min-1. Titration with purified pig liver cytochrome b5, demonstrated a 4-fold maximum stimulation at a cytochrome b5 to a P-450 molar ratio of 1-2. Rabbit lung P-450PG-omega formed a typical type I binding spectrum upon the addition of prostaglandin E1 with a calculated K8 of 1 microM, which agreed reasonably well with the kinetically calculated Km of 3 microM. Cytochrome P-450PG-omega was isolated as a low-spin isozyme with a lambda max (450 nm) in the CO-difference spectrum distinguishable from P-450I (451 nm) and P-450II (449 nm). Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis demonstrated that although purified P-450PG-omega had a relatively low specific content (12.1 nmol mg-1), it appeared homogeneous with a calculated minimum Mr of 56,000, intermediate between rabbit LM4 and LM6. When lung microsomes from pregnant and nonpregnant rabbit were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a protein band, with a Mr identical to P-450PG-omega, was observed in the pregnant rabbit, whereas this band appeared to be very faint or absent in microsomes from the nonpregnant rabbit. Purification of cytochromes P-450 from nonpregnant rabbit lung yielded only P-450I and P-450II. P-450PG-omega appears to be a novel rabbit P-450, possessing high activity towards omega-hydroxylation of prostaglandins, and is greatly induced during pregnancy in rabbit lung.

The purpose of this study was to determine the effect of varying prosthetic shank mass, while maintaining the mass centre location and moment of inertia, on the swing phase kinematics, kinetics and hip muscular effort of free speed above-knee (AK) amputee gait. Six AK amputees, wearing similar prosthetic designs, had three load conditions applied to their prosthetic shank: 1) Load 0-unloaded (X - 39.1% sound shank mass), 2) Load 1-75%, and 3) Load 2-100% sound leg mass. Despite increases in shank mass from 1.33 to 3.37 kg the AK amputee was able to maintain a consistent swing time and walking speed. As load increased, there were significant changes in the maximum knee and hip displacements, as well as phasic shifting. The prosthetic knee Resultant Joint Moment (RJM) was negligible while the shank was accelerating (periods 1 and 2), but was a major contributor during shank deceleration (periods 3 and 4). During periods 1 and 2 the principle contributors to the shank acceleration (forces resisting excessive knee flexion) were the gravitational moment (S-G) and the moment due to thigh angular acceleration (S-AT). During the periods of shank acceleration (sections 1 and 2), there was not a significant increase in the hip muscular effort. However, during sections 3 and4, the periods associated with shank deceleration, there were siginficant increases in the hip muscular effort. The hip muscular effort for the complete swing phase increased as load increased by 36.7% and 71.3% for loads 1 and 2. Despite the significant increases in hip muscular effort, four of the six subjects preferred load 1 condition.

Cigarette smoking is a well-known risk factor for acute myocardial infarction and sudden death. However, a history of smoking consistently has been associated with better hospital outcome in patients with acute myocardial infarction. The mechanism for the better outcome in smokers is not clear. It has been suggested that nicotine may have a “preconditioning-like” effect. This study assesses whether nicotine attenuates myocardial infarct size.

Because of their high oxygen-carrying capability and small particle size, it has been suggested that perfluorochemical emulsions may be useful to reduce reperfusion injury after coronary artery occlusion and reperfusion. We tested the ability of Fluosol and a more concentrated perfluorochemical emulsion (perflubron) to decrease infarct size in anesthetized rabbits undergoing 30 min of coronary occlusion and 4 h of reperfusion. All rabbits were ventilated with 100% oxygen. Treatment was begun at 25 min of coronary occlusion, 5 min before reperfusion. Rabbits were randomized to receive saline (10 ml/kg, n=15), Fluosol (30 ml/kg, n=15), or a perflubron emulsion (10 ml/kg, n=16), or the perflubron emulsion vehicle (10 ml/kg, n=15). Collateral blood flow during occlusion was measured with radioactive microspheres. The size of the ischemic region at risk was determined by in vivo injection of blue dye and infarct size by in vitro tetrazolium staining. We found that all groups were equally ischemic during occlusion, and that risk zone sizes were comparable. Heart rate and systemic arterial pressure were also similar among groups. Infarct size expressed as a percentage of the risk zone was 30±4 % in saline-treated rabbits, 27±4 % in Fluosol-treated rabbits, and 21±4 % and 21±3 % in perflubron emulsion and perflubron emulsion vehicle treated rabbits, respectively. There was a trend for both perflubron emulsion and perflubron emulsion vehicle groups to have smaller infarcts; however neither perfluorocarbon emulsion nor the emulsion vehicle significantly reduced infarct size compared with saline treatment. Thus, at the doses used in this study neither Fluosol non perflubron emulsion, when given just before reperfusion, significantly reduced infarct size in this rabbit model.

Summary Successive ischemic episodes are commonly seen in clinical and experimental cardiology. Although prolonged abnormalities of the canine myocardium have been described following a single ischemic episode, it is not known whether myocardial injury is cumulative following multiple ischemic episodes. Dogs were subjected to three 15-min left anterior descending coronary artery occlusions, each followed by 30 min of reperfusion.In vivo biopsies were obtained for biochemical analysis before and during the first occlusion and 30 min into each reperfusion period. ATP and creatine phosphate (CP) fell in the endocardium during occlusion by 24% and by 69% respectively (both p<.0001). While CP recovered during each reperfusion period, ATP remained significantly depressed. Loss of membrane-permeable purine nucleotide synthesis precursors occurred with the first reperfusion period but not with the second and third reperfusion periods. Therefore, reperfusion following one 15-min coronary occlusion is associated with severe depression of myocardial high energy phosphates; however, two additional occlusions do not cause a further decrease of these substances when intermittent reperfusion is allowed for 30 min.

Potential errors in decoding genetic information are corrected by tRNA-dependent amino acid recognition processes manifested through editing reactions. One example is the rejection of difficult-to-discriminate misactivated amino acids by tRNA synthetases through hydrolytic reactions. Although several crystal structures of tRNA synthetases and synthetase-tRNA complexes exist, none of them have provided insight into the editing reactions. Other work suggested that editing required active amino acid acceptor hydroxyl groups at the 3' end of a tRNA effector. We describe here the isolation of a DNA aptamer that specifically induced hydrolysis of a misactivated amino acid bound to a tRNA synthetase. The aptamer had no effect on the stability of the correctly activated amino acid and was almost as efficient as the tRNA for inducing editing activity. The aptamer has no sequence similarity to that of the tRNA effector and cannot be folded into a tRNA-like structure. These and additional data show that active acceptor hydroxyl groups in a tRNA effector and a tRNA-like structure are not essential for editing. Thus, specific bases in a nucleic acid effector trigger the editing response.

Summary It has been reported that agents having the ability to scavenge oxygen-derived free radicals reduce the severity of ventricular arrhythmias that occur after brief coronary occlusion and reperfusion. Superoxide dismutase plus catalase (SOD + CAT) or placebo was administered in a blinded randomized fashion prior to coronary occlusion in rats (n = 25 each group) undergoing a 5-min left coronary occlusion followed by 15 min of reperfusion. During reperfusion, ventricular tachycardia (VT) developed in 96 % of animals in both groups. Reperfusion ventricular fibrillation (VF) developed in 60 % of the placebo group vs 56 % in the SOD + CAT group (p =1.0). Irreversible VF occurred in 40 of the placebo group vs 20 % in the SOD + CAT group (p = 0.22). Atrioventricular block occurred in 12 % of placebo and 4 % of SOD + CAT animals (p = 0.61).

Above-knee (AK) amputees generally walk slower than normal subjects. To understand why this occurs, the kinetics (forces and moments) of walking, at different walking speeds, must be examined. The purpose of this study was to determine the effect of walking speed on stride length, stride and swing times, the knee and hip displacement and torque patterns, and the roles of the gravitational forces and interactive moments associated with thigh motion. Three subjects were filmed walking at three self-selected walking speeds (slow, natural, fast). The swing phase was analyzed in detail using the inverse dynamics approach. As walking speed increased, the stride length increased while stride and swing times decreased. The maximum knee flexion and initial hip .flexion peaks increased as walking speed increased. As walking speed increased, the knee flexor torque during terminal swing increased, and this was necessary to slow the leg down in preparation for the subsequent weightbearing stage. The principle moment limiting knee flexion was the gravitational moment, which was assisted by the interactive moments associated with thigh acceleration and velocity (L-AT and L-VT). The hip muscular torque pattern was characterized by four phases—initial flexor and extensor, final flexor and extensor. The initial extensor torque decelerated the thigh, which in turn contributed to the term L-AT. L-AT assisted in accelerating the leg and resisted knee flexion and initiated knee extension. The final hip extensor torque slowed down the thigh and maintained the knee in extension, through the term L-AT in preparation for footstrike.

Abstract

Vegetative bacilli and refractile endospores of Bacillus subtilis 168 were disrupted by homogenization with glass beads and fractionated by differential centrifugation. Most of the protein of endospores was particulate, whereas for bacilli most was soluble. Alanine racemase activity was sixfold higher in extract of endospores than in extract of bacilli and was particulate, whereas the enzyme from bacilli was soluble. The specific activities of seven other enzymes involved in peptidoglycan and teichoic acid biosynthesis were higher in extracts of bacilli than in those of endospores. The results suggest that restoration of activities of these seven enzymes to vegetative levels occurs during germination and outgrowth.

Two studies investigated the effects of eye movements on the rate of discovery and the vividness of visual images. Eye movements were manipulated by having three conditions: (1) The Ss were instructed to make eye movements while generating images to noun pairs; (2) the Ss were instructed not to make eye movements, but to think about making eye movements while generating images to noun pairs; (3) the Ss were instructed not to make eye movements and not to think about making eye movements while generating images to noun pairs. In addition, the ease of generating images was manipulated by using noun pairs that differed in their image-evoking capacity; five of the noun pairs consisted of high imagery-evoking nouns and five consisted of low imagery-evoking nouns. The two experiments were similar, with the exception that a between-groups design was used in Experiment 1, whereas Experiment 2 employed a within-Ss design. The results of both experiments showed highly significant effects of noun-pair type on both the rate of discovery and the vividness of images, with the fastest and most vivid images occuring to the high-imagery noun pairs. The effects of the eye-movement conditions on the rate of discovery and the vividness of the images were not significant in either experiment, and these findings are discussed in terms of the relationship of ocular activity to imagery. [ABSTRACT FROM AUTHOR]

We present scintillation noise profiles captured at the Observatorio del Teide, Izaña, Tenerife, over a one-week period in 2017 September. Contemporaneous data from the Birmingham Solar Oscillations Network (BiSON) and the Stellar Activity (STELLA) robotic telescopes provides estimates of daily atmospheric extinction allowing the scintillation noise to be placed within the context of overall atmospheric conditions. We discuss the results both in terms of the impact on BiSON spectrophotometer design, and for astronomical observations more generally. We find that scintillation noise power reduces by half at about 5 Hz, and is reduced to one tenth between 20 and 30 Hz even during periods of mild Calima, where visibility is reduced due to high concentrations of mineral dust in the atmosphere. We show that the common accepted exposure time of <10 ms for limiting the effect of scintillation noise in ground based photometry may be increased, and that depending on the application there may be little benefit to achieving exposure times shorter than 50 ms, relaxing constraints on detector gain and bandwidth.