cssi/SciSciGPT-SciSciNet huggingface dataset:
Approximations of Queue Dynamics and Their Application to Adaptive Routing in Computer Communication Networks

Various adaptive algorithms have been proposed for routing, flow and congestion control in packet-switched computer communication networks. In most of them, information on queue lengths, or equivalently, time delays, at various points in the network is required for proper adaptation. Since up-to-date information is not always available, these quantities must be estimated based on prior information. This paper presents approximations for the dynamic behavior of the M/M/1 queue which is used to yield the desired estimates of queue lengths. Based on the assumption of finite (but arbitrarily large) storage, a closed form expression for the evolution in time of the queue length distribution is obtained. From this expression various approximations for estimated queue length are extracted. A simple expression for the "relaxation time" of the queue is also deduced as a function of utilization factor and service time. The approximations are applied to a simple adaptive routing example in which packets are routed along the transmission path having the shortest estimated queue, based on delayed information.
U–6Nb shear stress relaxation in compression waves (IJP 585-AV)

Abstract When uranium alloyed with 6-wt% niobium (U–6Nb) is rapidly compressed in uniaxial strain experiments, shear stress is observed to relax with a characteristic time of 30 ± 7 ns. In shock wave experiments, this relaxation inhibits the development of an elastic precursor commonly seen in other materials. When U–6Nb is cold-rolled to pre-twin and significantly increase the density of dislocations in the material, stress relaxation effects are diminished suggesting that twinning causes relaxation in the un-worked material. Separate ramp wave compression experiments produce effects that agree with those observed in shock-loading experiments. A phenomenological model is introduced that allows accurate simulation of all experiments. Estimates of residual shear stress after relaxation are obtained.
Separation of amino acid naphthylamidases in human plasma on sephadex G-200 and DEAE-cellulose.

Abstract Enzymatic activities for the hydrolysis of s-naphthylamides of various amino acids (alanine, arginine, aspartic acid, glutamic acid, leucine, lysine, phenylalanine, tyrosine and valine) in human plasma were separated by column chromatography on Sephadex G-200 and DEAE-cellulose. The distribution of activities toward naphthylamides of aspartic acid and glutamic acid was identical, but different from that toward leucine naphthylamide. The distribution of activities toward naphthylamides of other aminoacids (alanine, arginine, lysine, phenylalanine, tyrosine and valine) was generally like that toward leucine naphthylamide. The molecular weight or aspartyl of glutamyl s-naphthylamidase was 190,000, whereas that of leucyl s-naphthylamidase was 160,000. Glutamyl s-naphthylamidase was separated from leucyl s-naphthylamidase by Sephadex G-200 and then DEAE-cellulose. Properties of purified s-naphthylamidase directed toward the aspartyl or glutamyl substrates were different from those of leucyl s-naphthylamidase. Glutamyl s-naphthylamidase was markedly activated by CA ++ , had a pH optimum at 7.5, and a K m value of 1·2 × 10 −3 M. Ca ++ had no effect on leucyl s-naphthylamidase. Its pH optimum was 6·6 and the K m value was 3·3 × 10 −4 M. It is concluded that the enzyme in human plasma which hydrolyzes either glutamyl s-naphthylamide or aspartyl s-naphthylamide (aminopeptidase A) is a distinct enzyme.
Repeated photographic laboratory calibrations of two reseau cameras

Abstract Several attempts were made to derive, by means of a given single fan of collimators, the interior orientation parameters and the overall lens distortion for two reseau lenses, a Wild Universal-Aviogon and a Zeiss Oberkochen Pleogon-AR. A number of procedural improvements were incorporated during the two-and-a-half year period between the first and the last calibrations. A comparison of the different results obtained indicates that both cameras have undergone changes between calibrations.
Dual composition control in a novel batch distillation column

The newly emerging batch column called the middle vessel column presents the problem of dual composition control similar to the continuous distillation column. The degree of interaction between the two composition control loops can be assessed using the relative gain array technique. This paper presents the RGA analysis for the middle vessel column dual composition control problem. The analysis shows that the interaction between the two loops for this new column is mostly negligible due to the large time constant of the middle vessel. Furthermore, with the middle vessel column, there is a greater likelihood of reducing the interaction between control loops by varying the parameter q‘ (the ratio of the vapor rate in the rectification section of the column to the vapor rate in the stripping section of the column).
A Factorization Algorithm for Wave Propagation in Periodic Structures with Application to Torsional Waves in an Infinite Cylinder

In this paper we introduce a fundamentally new concept in the field of wave-propagation in periodic structures. We show that a phenomenal amount of simplification can be achieved by using symmetry arguments. Problems which ordinarily lead to (2 n × 2 n ) determinantal eigenvalue equations, can effectively be reduced to two ( n × n ) determinantal equations. We state the final result in the form of a factorization theorem and then with the help of a simple problem, we show the superiority of this new result over the traditional methods of solution.
Thin-layer ablation of human esophageal epithelium using a bipolar radiofrequency balloon device.

Background The goal of this study was to determine the optimal treatment parameters for the ablation of human esophageal epithelium using a balloon-based bipolar radiofrequency (RF) energy electrode.
Tomography transform and inverse in geometrical optics

Geometrical optics is applied in a modeling of the forward-propagation process for transmission tomography with diffracting sources. The forward process is described mathematically as an optical tomography transform of an object function into a set of measured projection data representing line integrals of that parameter function. A recursive scheme is devised for the inverse process of reconstruction of the object parameter function from its forward projections. Ultimately, a new computational scheme is presented for the fast and accurate reconstruction of the object function. Ray-tracing methods lead to a representation of the forward-propagation process as a system of linear equations. Simultaneous algebraic reconstruction methods are applied in the discretized inverse process.
Lewis Acid-Induced N-Methyleneamines as Initiators in the Synthesis of Secondary Amine-Terminated Polymers

The cationic polymerization of poly(tert-butyl vinyl ether) using N-methyleneamine equivalents derived from a Lewis acid/1,3,5-trimethylhexahydro-1,3,5-triazine (TMTA) co-initiating system is reported. The resulting polymers possessed secondary amine functionality at the chain terminus, verified by derivatization with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) and subsequent analysis with GPC-UV (470 nm) and 1 H NMR.
The Effect of Prepartum Vitamin A Supplementation on the Health and Performance of the Young Calf

Summary The effects of feeding 1million I.U. of vitamin A, in the form of dehydrated alfalfa leaf meal, the ester form of vitamin A and the alcohol form of vitamin A, daily to cows 30 days prepartum on the blood plasma levels of carotene and vitamin A, liveweight changes, feed consumption and incidence of scours of calves from birth to 28 days of age have been studied. Carotene levels in the blood plasma of calves from dams fed the alcohol form of vitamin A were significantly higher during the experimental period than calves from dams in the other dietary groupings. Also, calves from dams receiving the ester form of vitamin A were significantly higher in plasma carotene than calves from dams fed alfalfa leaf meal. Plasma of calves from cows fed vitamin A as either ester or alcohol was significantly higher in vitamin A than that of calves from the basal dams or those fed alfalfa leaf meal. Greater liveweight increases were observed in calves from dams fed either form of vitamin A than in calves from dams fed the basal ration alone or with alfalfa leaf meal. In addition, calves from dams fed alfalfa leaf meal made greater increases in liveweight during the entire experimental period than calves from basal dams. There were no statistical differences found in feed consumption. Incidence of scours was significantly lower in calves from dams fed either form of vitamin A than that observed in calves from control dams. Calves from dams fed alfalfa leaf meal had fewer cases of scours than calves from control dams.
A Dimeric Structure for Archaeal Box C/D Small Ribonucleoproteins

Methylation of ribosomal RNA (rRNA) is required for optimal protein synthesis. Multiple 2′-O-ribose methylations are carried out by box C/D guide ribonucleoproteins [small ribonucleoproteins (sRNPs) and small nucleolar ribonucleoproteins (snoRNPs)], which are conserved from archaea to eukaryotes. Methylation is dictated by base pairing between the specific guide RNA component of the sRNP or snoRNP and the target rRNA. We determined the structure of a reconstituted and catalytically active box C/D sRNP from the archaeon Methanocaldococcus jannaschii by single-particle electron microscopy. We found that archaeal box C/D sRNPs unexpectedly formed a dimeric structure with an alternative organization of their RNA and protein components that challenges the conventional view of their architecture. Mutational analysis demonstrated that this di-sRNP structure was relevant for the enzymatic function of archaeal box C/D sRNPs.
Toward network data independence

A number of researchers have become interested in the design of global-scale networked systems and applications. Our thesis here is that the database community's principles and technologies have an important role to play in the design of these systems. The point of departure is at the roots of database research: we generalize Codd's notion of data independence to physical environments beyond storage systems. We note analogies between the development of database indexes and the new generation of structured peer-to-peer networks. We illustrate the emergence of data independence in networks by surveying a number of recent network facilities and applications, seen through a database lens. We present a sampling of database query processing techniques that can contribute in this arena, and discuss methods for adoption of these technologies.
Three Troubadour Poems with Historical Overtones

SOUTHERN FRANCE in the twelfth and thirteenth centuries witnessed significant changes in daily life: for example, the increasing emancipation of towns from feudal control and the rise of the bourgeoisie. It was the scene of numerous territorial struggles among local lords, such as the vigorously pressed claims of the dukes of Aquitaine and their successors, the royal house of England, to Toulouse and other neighboring domains. It was also invaded from the outside, both by force and by marriage: Barcelona and Aragon acquired considerable footholds in Provence, Montpellier, and elsewhere. Furthermore, the South participated significantly in the Crusades to the Holy Land. Of much greater consequence, however, was its involvement in the "Albigensian Crusade"; this brutal war led to the extermination of the Cathars scattered over the region, the establishment of the Inquisition, the end of the house of Toulouse, the devastation of vast areas and important cities. One might expect to find these events mirrored in the poems of the troubadours, who lived at this time and in this part of France; and they do have some place there. Naturally, history would be at best incidental in the amorous canso, the major genre of Old Proven,al poetry, and the one which has influenced most profoundly the subsequent course of European literature; but several less highly regarded forms of troubadour verse come closer to the economic, social, and political aspects of medieval life. Among these are the planh or funeral lament, the tenso or poetic debate, the all-purpose cobla consisting of a single stanza, and the sirventes, which often satirizes contemporary morals, heaps abuse on some individual, or voices the author's reactions to what is going on in the world around him. The present article contains three such poems, never before critically edited, which possess substantial historical as well as literary interest.
A higher order method for multiple zeros of nonlinear functions

A method of order three for finding multiple zeros of nonlinear functions is developed. The method requires two evaluations of the function and one evaluation of the derivative per step.
Variation in the xanthophyll and carotene content of lucerne, clovers and grasses

The xanthophyll and carotene contents of eleven lucerne clones were found to be higher during September and November than during June and July. Both carotenoids reached a maximum at or before first flowering and then declined as blossoming progressed. Lutein decreased in November while violaxanthin increased. Six grasses and four legumes were analysed for the principal leaf xanthophylls, lutein, violaxanthin and neoxanthin, as well as total xanthophyll and carotene.
Fiberoptic Bronchoscopic Cryotherapy in the Management of Tracheobronchial Obstruction

Cryotherapy is used for endoscopic management of tracheobronchial obstruction (TBO). This study describes the use of a flexible cryoprobe for cryotherapy using nitrous oxide as a cryogen through a fiberoptic bronchoscope. The study group consisted of 22 patients, ages ranging from 28 to 82 years. Twenty patients had malignant TBO and two had bronchial obstruction (BO) following lung transplantation. Benign BO was first dilated with a balloon and followed with cryotherapy. Eighteen of the 20 malignant endobronchial lesions were completely removed. In three of these patients, the airway remained occluded due to extrinsic compression. Cryotherapy offers an alternative to Nd:YAG laser in the management of TBO. Cryotherapy offers other advantages such as being inexpensive, safe for the operator, and safe for other members of the team. Similarly for the patient, there is no danger of bronchial wall perforation or endobronchial fires, cryotherapy can be done under local anesthesia with conscious sedation, and it can be performed in an endoscopy suite.
Developing a predictive group-contribution-based SAFT-VR equation of state

Abstract The hetero-segmented version of the statistical associating fluid theory for potentials of variable range (hetero-SAFT-VR) is used to develop a predictive molecular-based group-contribution SAFT-VR equation of state (GC-SAFT-VR). The hetero-SAFT-VR approach models molecules composed of segments of different size and/or energies of interaction enabling an accurate description of real molecules composed of different functional groups. The differences in interactions between functional groups are maintained throughout the theory in contrast to other approaches in which the parameters for functional groups are averaged in order to model a molecule as a homonuclear chain with “group-averaged” parameters. Through the GC-SAFT-VR approach we can study the effect of molecular functionality and topology on the thermodynamic properties of real fluid systems, since parameters are determined for each functional group and chain connectivity is explicitly specified. In this initial study GC-SAFT-VR parameters are developed for key organic functional groups (CH 3 , CH 2 , CH 2 CH, C O, C 6 H 5 , OCH 3 and OCH 2 ) by fitting to experimental vapor pressure and saturated liquid density data for a selected group of compounds that contain these functional groups. The transferability of the parameters obtained is tested by comparing theoretical predictions with experimental data for pure fluids not included in the fitting process and binary mixtures. Using the GC-SAFT-VR approach good agreement is obtained between experimental data and the theoretical predictions for pure substances, including isomers, and their mixtures. The GC-SAFT-VR approach is able to accurately predict the effect of molecular functionality on mixture phase behavior without fitting to any experimental data for the system being studied.
Performance evaluation of small-batch container delivery systems used in lean manufacturing – Part 1: system stability and distribution of container starts

In lean manufacturing, milk run (MR) systems represent route-based, cyclic material-handling systems that are used widely to enable frequent and consistent deliveries of containerised parts on an as-needed basis from a central storage area (the ‘supermarket’) to multiple line-side deposit points on the factory floor. MR systems generally result in short lead times, low variability, and low line-side inventory levels. In the first part of this two-part paper, a basic, single-tugger MR system is described. Stability conditions are derived with respect to the ‘physical capacity’ of the tugger, and the ‘time utilisation’ of the driver/material handler, both of which are key criteria since the number of containers that can be delivered during each MR is limited, and each MR targets a prescribed cycle time to ensure timely and consistent deliveries. We also derive the distribution of the number of containers requested per MR, which allows the model to estimate the probability of exceeding the physical capacity ...
Comparative bread quality of white flour and whole grain flour for hard red spring and winter wheat

Superior bread-making quality is a primary objective for most hard red wheat (Triticum aestivum L.) breeding programs. Milled white flour is traditionally used to measure quality. There is increasing demand in the domestic market for whole grain bread products. The objective of this research was to determine the relationship of bread quality parameters based on white flour versus whole wheat flour in a set of hard red spring and hard red winter wheat genotypes. Quality evaluations were conducted on sets of genotypes grown in four environments for both wheat classes. Correlations of genotype performance for white flour versus whole meal varied with the traits. Protein levels were highly correlated, but correlations tended to decrease as dough was processed into a final product. This was especially true for hard red spring wheat genotypes. Mixograph tolerance of white flour versus whole meal was correlated highly for both spring and winter wheat, while water absorption was correlated poorly for both classes of wheat. Correlations for final loaf volume of whole wheat versus white flour was significant in two environments, and ranged from 0.08 to 0.72 for spring wheat genotypes. Correlations for loaf volume were significant in all environments, and ranged from 0.76 to 0.92 for winter wheat genotypes. In general, our data indicated that quality measured on white flour could be used as an estimate of whole wheat performance, but that identification of the best genotypes for whole wheat performance may require separate quality analysis.
The carboxy-terminal segment of the yeast α-factor receptor is a regulatory domain

Abstract The α-factor receptor is rapidly hyperphosphorylated on Thr and Ser residues in its hydrophilic C-terminal domain after cells are exposed to pheromone. Mutant receptors in which this domain is altered or removed are biologically active and bind α-factor with nearly normal affinity. However, cells expressing the mutant receptors are hypersensitive to pheromone action and appear to be defective in recovery from α-factor-induced growth arrest. Mutant receptors with partial C-terminal truncations undergo ligand-induced endocytosis, suggesting that down-regulation of receptor number is not the sole process for adaptation at the receptor level. A mutant receptor lacking the entire C-terminal domain (134 residues) does not display ligand-induced endocytosis. Genetic experiments indicate that the contribution of SST2 function to adaptation does not require the C-terminal domain of the receptor.
MnSOD antisense treatment and exercise-induced protection against arrhythmias.

Abstract Exercise provides protection against ischemia–reperfusion (I-R)-induced arrhythmias, myocardial stunning, and infarction. An exercise-induced increase in myocardial manganese superoxide dismutase (MnSOD) activity has been reported to be vital for protection against infarction. However, whether MnSOD is essential for exercise-induced protection against ventricular arrhythmias is unknown. We determined the effects of preventing the exercise-induced increase in MnSOD activity on arrhythmias during I-R resulting in myocardial stunning. Male rats remained sedentary or were subjected to successive bouts of endurance exercise. During in vivo myocardial I-R, the incidence of arrhythmias was significantly lower in the exercise-trained rats than in the sedentary rats as evidenced by the arrhythmia. When exercised rats were pretreated with antisense oligonucleotides directed against MnSOD, protection from arrhythmias was attenuated. Moreover, I-R resulted in significant increases in nitro-tyrosine (NT) in the sedentary group. Exercise abolished this I-R-induced NT formation but this protection was unchanged by antisense treatment. Protein carbonyls were increased by I-R, but neither exercise nor antisense treatment impacted carbonyl formation. These data demonstrate that an exercise-induced increase in MnSOD activity is important for protection against arrhythmias. The mechanism by which MnSOD provides protection does not appear to be linked to protein nitrosylation or oxidation.
Latency for the perceived offset of brief target gratings

Observers adjusted a brief auditory probe to coincide with the phenomenal offset of a 50-msec target grating of varying spatial frequency. Increasing spatial frequency increased the chosen latency for the probe, while increasing grating luminance decreased the chosen latency for the probe. These results were interpreted in terms of the sensitivity of off-responses in the visual system to these stimulus variables. These latencies for off-responses were specifically distinguished from visual persistence which is generally longer lasting and exhibits opposite relationships with the same stimulus variables.
Chondrocyte volume fraction distribution in porcine septal cartilage: An initial stereoscopic evaluation:

This study uses stereology to determine the volume fraction distribution of chondrocytes throughout septal cartilage. En bloc submucous resection of septal cartilage from four different age groups was performed. Each age group contained three pigs. The weight, volume, and dimensions of the septi were determined. The septi were fixed, embedded in plastic, sectioned vertically at regular intervals along their anterior-posterior axis, and stained with toluidine blue. Each section was further stratified horizontally to allow chondrocyte volume fraction changes to be observed as a function of the two-dimensional location within the septum. The volume fraction of the chondrocytes within the septal cartilage was obtained through light microscopy and stereologic technique. Nested analysis of variance for age groups, individuals within age groups, and locations on the septum was performed. Additionally, unequal number-comparison tests for age groups were calculated. Gross septal parameter changes regarding weight,...
Effects of dextroamphetamine and contingency management on a preschooler with ADHD and oppositional defiant disorder

Abstract A double-blind time-scries design was used to evaluate the effects of dcxtroamphetamine (10 nig and 5 nig/day) on the work behavior, play interaction, and aggressiveness of a 4-year-old boy with Attention Deficit Hypcractivity Disorder and aggressive, oppositional behavior who had not responded sufficiently to behavioral interventions in a day treatment setting. Significant changes in work behavior and aggressiveness were attributable to the medication, with episodes of tantrums declining from an average of nearly four per day during baseline and placebo to less than one per day during active medication. The results are discussed with respect to: (1) the significance of behavior change in relation to mild side effects, (2) the maintenance of treatment changes 2 years after the initial drug trial, and (3) the implications of our findings for research on the effects of combined drug and behavioral interventions with children under 6 years of age. J. Am. Acad. Child Adolesc. Psychiatry , 1988, 27. 2:175–178.
Zoophysiology: Nervous System Regeneration in the Invertebrates

This monograph is an excellent and long-overdue summary of cell-body and axonal regeneration of neurons in many invertebrate phyla (Cnidaria, Ctenophora, Platyhelminthes, Nemertea, Nematoda, Annelida, Arthropoda and Mollusca). The monograph provides a rather nice balance between an encyclopedic description of regenerative capabilities in different phyla (Chapter 2) and general descriptions of important processes in nerve regeneration (Chapter 3: ‘Early responses to neuronal injury’, Chapter 4: ‘Pathfinding by the growth cone’ and Chapter 5: ‘Synapse formation and alteration during regeneration’).This monograph is particularly valuable for several reasons. First, it introduces research scientists and clinicians to neuronal regenerative processes common in invertebrates that are present, but not common, in vertebrates (especially mammals); for example, the regeneration of nerve cell bodies, the survival for weeks to years of axonal segments severed from their cell bodies, and the high specificity of regenerated connections. Second, it provides an overview of regenerative processes that are common to both invertebrates and vertebrates; for example, changes in excitability following axotomy, sealing of cut axonal ends, morphology and physiology of growth cones, and pathfinding by growth cones. Third, it provides readers with a bibliography that lists most of the important papers in this somewhatignored field. From these papers, in turn, interested readers can access all the research literature of invertebrate neuronal regeneration. Finally, this monograph is exceedingly valuable because it demonstrates clearly why mechanisms of neuronal regeneration are often more easily addressed in invertebrates whose simpler nervous systems have identifiable neurons. The principles learned from these invertebrate systems have proven applicable to mammals and have provided insights to the repair of human neurons.
Does "craving" carve nature at the joints? Absence of a synonym for craving in many languages.

Abstract Introduction Craving is a term commonly used by North American lay people, and is also used as an important category in psychological and addiction research. However, difficulties in defining craving suggest that it may not be a natural category. Methods Assuming that lexicalization of a concept is an indicator of its importance and/or universality, the presence of synonyms for craving is examined in a range of natural languages, using both dictionaries and native speaker informants. Related words, such as “love,” “like,” “urge,” “desire,” “adore” and “addiction” are also explored in 20 languages, in terms of meaning and the domains of life to which these words are applied. Results Based on automated translations, 64% of 25 languages have a craving synonym, and based on native speaker, only 17% of 20 languages lexicalize craving; when there is a synonym, it seems to mean a desire for a potential ingestant or a drug, that is, it is a desire restricted to certain domains of activity. Discussion The concept of “craving” appears to be limited in its importance and relevance in languages and cultures outside of English and North America. This finding has important implications for the understanding of “craving” as a natural category in the study of drug and other addictions. A similar though less extensive lack of synonyms for “addiction” is also reported.
Antihypertensive Therapy with Prazosin in Patients with Left Ventricular Dysfunction: Improvement in Cardiac Performance and Exercise Tolerance

Although the relationship between blood pressure and cardiac performance has been widely recognized, there are few published clinical observations concerning the effect of blood pressure control on cardiac function. We evaluated the effect of prazosin, an antihypertensive agent which also improves hemodynamic measurements in normotensive patients with heart failure, in 16 patients with moderate hypertension and reduced ejection fractions. Therapy with digoxin and diuretics was continued throughout the study, but other antihypertensive agents were withdrawn at least one week prior to the initiation of the study. Measurements of ejection fraction, cardiothoracic ratio and the duration of maximal treadmill exercise were made before and after two months of antihypertensive therapy with prazosin. On prazosin, blood pressure fell from a mean of 169/103 to 141/84. Excellent control was achieved in 13/16 patients and significant reductions were noted in the remaining three. Concomitantly, ejection fraction rose from .38 ± .02 (SEM) to .43 ± .03 (P
Design, in vitro stability, and ocular hypotensive activity of t-butalone chemical delivery systems

The objective of this work was to synthesize two bioreversible diacyl derivatives of t-butalone (chemical delivery systems), determine their chemical and in vitro stability, and investigate their potential use as topical antiglaucoma agents. The stability of these compounds was determined in isotonic phosphate buffers (pH range 5-8) and in selected biological media, including human whole blood, rabbit and rat blood, and the anterior segment tissues of rabbit. The ocular hypotensive activity of these compounds in unrestrained, normotensive albino rabbits was determined with a pneumatonometer. The two compounds were stable at lower pH. The stability decreased as the pH increased, suggesting their lability to base-catalyzed hydrolysis. These compounds exhibited significant differences in the hydrolytic rates in the whole blood among species examined (rat > rabbit > human). The observed rates of disappearance in different ocular tissues were indicative of relative enzyme activity in these media (iris-ciliary body > cornea > aqueous humor). The two compounds exhibited a significant ocular hypotensive activity (P < 0.01) at 2% dose level. The peak activity was found between 2 and 4 h, and the activity was maintained for 4.5 to 7 h. The dipivalyl derivative of t-butalone exhibited more pronounced decrease in intraocular pressure than that of diisovaleryl derivative. The present study suggests the possible use of diacyl derivatives of t-butalone as ocular hypotensive agents.
The statistical and fractal properties of surface reflectivity of raw chicken tissue with application to public health safety

Images of packaged raw chicken purchased in neighborhood supermarkets were captured via a digital camera in laboratory and home settings. Each image contained the surface reflectivity information of the chicken tissue. The camera's red, green and blue light signals fluctuated and each spectral signal exhibited a random series across the surface. The Higuchi method, where the length of each increment in time (or spatial) lag is plotted against the lag, was used to explore the fractal property of the random series. (Higuchi, T., "Approach to an irregular time series on the basis of fractal theory", Physica D, vol 31, 277-283, 1988). The fractal calculation algorithm was calibrated with the Weierstrass function. The standard deviation and fractal dimension were shown to correlate with the time duration that a package was left at room temperature within a 24-hour period. Comparison to packaged beef results suggested that the time dependence could be due microbial spoilage. The fractal dimension results in this study were consistent with those obtained from yeast cell, mammalian cell and bacterial cell studies. This analysis method can be used to detect the re-refrigeration of a "left-out" package of chicken. The extension to public health issues such as consumer shopping is also discussed.
A developmental study of data envelopment analysis in measuring the efficiency of maintenance units in the U.S. air forces

Abstract : There are four basic questions related to efficiency and capability which are of particular interest to officials in the military services who are interested in better ways of evaluating military capability and efficiency: (1) What level of military capability can the services achieve with available resources? (2) What capability is required, and where are the shortfalls? (3) What resource acquisitions or redistributions are needed to achieve maximum improvement in efficiency and effectiveness? and (4) How can management systems be changed to improve the identification and correction of factors which limit the readiness and efficiency of our military operations? The last question, which differs in its emphasis from the other three, provides an opening to the topics that will be addressed in this report. In particular, reported are results from a study of DEA (Data Envelopment Analysis) as a method for evaluating the efficiency of Air Force Wings--or, more precisely, their maintenance operations--as elements in Numbered Units in the U.S. Air Force.
Serine/threonine protein kinases in Drosophila

The study of serine/threonine kinases in Drosophila is coming of age. Recently several kinases have been identified and their role in cell determination has been established. This review discusses these recent findings and describes the potential for genetic analyses of kinase activity and signal transduction.
The protein concentration of crude cell and tissue extracts as estimated by the method of dye binding: Comparison with the lowry method

Abstract The protein concentration of crude extracts from cultured cells and of subcellular fractions from rat tissues has been estimated both by the method of Bradford, involving the binding of Coomassie brilliant blue G-250, and by the procedure of Lowry et al. with the same preparation of bovine serum albumin as a common protein standard. Whereas the method of dye binding yielded significantly lower values than did the Lowry procedure, a consistent quantitative relationship existed between the values obtained by the two techniques. Evidence is provided that this discrepancy does not result from the presence in such complex biological mixtures of a class of small peptides, undetected by the method of dye binding, that react with the Lowry reagents.
Artificial muscle valves for responsive drug delivery systems

A controlled drug delivery system in which drug release is achieved by actuating an array of polymeric valves on a set of drug reservoirs is introduced. The valves are bilayer structures with one layer, a thin film of evaporated gold and the other, electrochemically deposited polypyrrole, which is also called “artificial muscle”. The valves are made in the shape of flaps fixed on one side to the valve seats. Drug reservoirs are covered by an array of such valves. Release of the drugs stored in the reservoirs is accomplished by bending the bilayer flaps back with a small applied bias. The fabrication procedures and proof-of-principle drug release experiments for this controlled drug delivery device are described. Energy consumption of this reversible valve design is compared with metal corrosion based valves developed earlier by other groups and our group.
A study of the reliability of the bureau of land management visual resource assessment scheme

Abstract Kopka, S. and Ross, M., 1984. A study of the reliability of the Bureau of Land Management visual resource assessment scheme. Landscape Plann., 11: 161–166. The Bureau of Land Management's visual resource assessment scheme was evaluated in the light of its internal consistency (reliability). Reliability, even under the most rigorous of training regimens, is weak. The validity of the whole visual resource management program of the Bureau of Land Management is therefore questionable. The paper offers some solutions to this problem in the conclusion.
Wideband Parametric Frequency Comb as Coherent Optical Carrier

We report the first use of the CW-seeded parametric comb as a multiwavelength source for coherent channel transmitters. The new comb source relies on a multistage parametric mixer design seeded by a single kilohertz-linewidth master laser. The resultant frequency comb provides more than 120 tones in a 100-nm-wide continuous band, all possessing kilohertz-scale linewidth inherited from the master laser. The applicability of the new comb source as a coherent channel carrier was quantified by error-vector magnitude and bit-error rate metrics of individual spectral lines modulated by QPSK signaling. The performance of the new source exceeded that of the standard tunable coherent transmitter while providing a qualitatively lower frequency uncertainty and drift.
Structural considerations for elastic magnetic electron-nucleus scattering

Abstract To explain the form factors obtained by magnetic electron scattering on 17 O it is clear that core polarization has to be taken into account. We discuss how this can be done by means of the Hartree-Fock theory. We note that projection from an intrinsic state of definite K gives an incorrect answer for weakly deformed systems such as 17 O and we present an alternative procedure for extracting the moments. Using a purely velocity dependent Skyrme interaction (only t 0 and t 1 are non-zero) a Hartree-Fock calculation is carried out for the seventeen-nucleon system. The calculation leads to a suppression of the M3 form factor. It is emphasized that the suppression arises from the fact that not only is the 16 O core deformed, but that spin-up particles have a different deformation than spin-down particles. This arises from the spin dependence of the interaction and from the Pauli principle. A peculiar feature with the interaction that is used is that the M5 form factor gets enhanced. This is attributed to the repulsive velocity dependent term in the interaction. The origin of the velocity dependence is discussed. The effect of the velocity dependence on the magnetic moment operator is also considered.
Stem cells: More like a man

Most female mammals experience a reproductive decline with increased age, previously attributed to the instability of ageing oocytes. But could it be due to a previously unrecognized stem-cell well drying up?
Automated performance assessment in interactive QA

In interactive question answering (QA), users and systems take turns to ask questions and provide answers. In such an interactive setting, user questions largely depend on the answers provided by the system. One question is whether user follow-up questions can provide feedback for the system to automatically assess its performance (e.g., assess whether a correct answer is delivered). This self-awareness can make QA systems more intelligent for information seeking, for example, by adapting better strategies to cope with problematic situations. Therefore, this paper describes our initial investigation in addressing this problem. Our results indicate that interaction context can provide useful cues for automated performance assessment in interactive QA.
Estimation of the drag forces acting on particle dendrites

Aerosol particles depositing in fibrous media form chainlike agglomerates (dendrites) on the fibers, and this process leads to substantial increases in filtration efficiency and pressure drop. The object of the present work is to develop an expression for the determination of the drag forces exerted on individual dendrites. This problem is central to the determination of pressure drop increase caused by particle deposition. A method for the approximate estimation of the drag force is developed, based on the concept of the ideal dendrite, which is defined as one composed of a chain of coaxial particles. The drag on an ideal dendrite is set equal to the drag that would be exerted on a half prolate spheroid of appropriate dimensions, placed in the position of the dendrite. Both tangential and normal drag components are obtained. The tangential component is derived by considering linear shear flow, whereas the normal component is derived by considering stagnation flow. The results are expressed in terms of correction factors for the Stokesian contributions of the particles that compose a dendrite. These correction factors can be used to estimate drag forces on dendrites deposited on plane or on curved surfaces. The theory is in good agreement with existing data.
Hypertension: Synergy of antihypertensives in elderly patients with CKD.

A recent study reports that the combination of an angiotensin-receptor blocker (ARB) and a calcium-channel blocker (versus a high-dose ARB) is associated with improved blood pressure control and reduced cardiovascular, cerebrovascular and heart failure events in an elderly chronic kidney disease population. This finding raises the possibility of using fixed-dose drug combinations to improve efficacy and compliance of antihypertensive medications.
Mass propagation of conifer trees in liquid cultures — progress towards commercialization

At Weyerhaeuser Company, somatic embryo production in liquid medium and manufactured seed delivery has been developed to reduce labor costs and increase efficiency of mass clonal propagation. We have scaled-up embryonal suspensor masses (ESM) of Douglas-fir in 1-l liquid medium flasks. Over 10,000 somatic embryos have been produced from a single flask. We have cryostored ESM of over 700 genotypes in liquid nitrogen. Somatic embryos of Douglas-fir have also been produced from liquid medium in a bioreactor. Different types of bioreactors are required for embryo multiplication and for cotyledonary embryo development. Over 250,000 Douglas-fir somatic seedlings from a large number of genotypes have been produced for clonal field tests.
Inappropriate coronary vasoconstriction in patients with coronary artery disease: A role for nifedipine?

Coronary arterial vasoconstriction, well recognized in Prinzmetal's variant angina, may participate in the pathogenesis of classic angina as well. Several recent studies in patients with obstructive coronary artery disease suggest that apparently spontaneous reductions in coronary blood flow can result in myocardial ischemia and even infarction. Evidence supporting the alpha adrenergic nervous system as a cause of such coronary vasoconstriction is reviewed, particularly the results of provocative testing with the cold pressor stimulus. Upon exposure of the skin to cold, patients with coronary artery disease demonstrate an inappropriate coronary vasoconstrictor response, often sufficient to produce angina. Normal patients, by contrast, show no change in coronary vascular resistance. In patients with a diseases coronary circulation, inappropriate vasoconstriction further restricts myocardial perfusion and appears to be little affected by beta adrenergic blocking agents or nitrates in the usual dosages. Nifedipine has proved effective in preventing coronary arterial spasm in patients with Prinzmetal's angina. Studies currently in progress suggest that it is also effective in blocking inappropriate coronary vasoconstriction in patients with typical angina. Nifedipine may thus be a useful addition to the treatment of ischemic heart disease.
Parental Support, Critical Consciousness, and Agency in Career Decision Making for Urban Students:

By investigating parental support as a distal variable and critical consciousness (CC) as a proximal variable, the authors targeted specific factors that may increase the perception of agency and, ...
Interactions among heart rate, autonomic activity, and arterial pressure upon the multiple repetitive extrasystole threshold in the dog.

Abstract The effects of heart rate, autonomic stimulation, and arterial blood pressure upon the multiple repetitive extrasystole threshold (MRET) were studied after coronary occlusion in anesthetized dogs. The MRET was unaffected by changes in heart rate. Sympathetic stimulation alone reduced the MRET from 52.4 ± 3.7 (mean ± SEM) to 41.3 ± 2.7 mA. Vagal stimulation alone was without effect. During simultaneous sympathetic and vagal stimulation the threshold was 48.7 ± 3.0 mA. This supports the contention that vagal activity serves mainly to oppose the tendency for sympathetic activity to lower the MRET. Reduction of blood pressure significantly decreased the average MRET from 38.6 ± 2.5 to 34.4 ± 1.8 mA. The presence of a post junctional site for the observed sympathetic-vagal interaction was investigated using isoproterenol infusion and vagal stimulatin. Infusion of isoproterenol lowered the MRET. Vagal stimulation in this situation raised the MRET; the effect varied directly with the rate of isoproterenol infusion. This suggests that part of the vagal effect is exerted postjunctionally; that is, directly upon the myocardial cell and not merely by inhibition of adrenergic transmitter release at sympathetic nerve endings.
Assessment of Transmural Distribution of Myocardial Perfusion With Contrast Echocardiography

Background—We hypothesized that by using our newly defined method of destroying microbubbles and measuring their rate of tissue replenishment, we could assess the transmural distribution of myocardial perfusion. Methods and Results—We studied 12 dogs before and after creation of left anterior descending coronary artery stenoses both at rest and during hyperemia (n=62 stages). Microbubbles were administered as a constant infusion, and myocardial contrast echocardiography (MCE) was performed with the use of different pulsing intervals. The video intensity versus pulsing interval plots derived from each myocardial pixel were fitted to an exponential function: y=A(1−eβt), where A reflects microvascular cross-sectional area (or myocardial blood volume), and β reflects mean myocardial microbubble velocity. The product A · β represents myocardial blood flow (MBF). Average values for these parameters were derived from the endocardial and epicardial regions of interest placed over the left anterior descending coro...
Ontogeny of mechanisms which regulate light/dark differences in retinal dopamine synthesis.

Abstract The ability of bicuculline, a GABA antagonist, to enhance dopamine (DA) synthesis in retinas of rats 1, 4, 7, 15 and 60 days after eye opening was assessed and compared to the time course of postnatal development of the light-induced increase in DA synthesis. The accumulation of dihydroxyphenylalanine (DOPA) following administration of the L-aromatic amino acid decarboxylase inhibitor, NSD 1015, was used to estimate DA synthesis. In dark-adapted rats, neither bicuculline nor light enhanced DOPA accumulation 1 day after eye opening, but on the remaining days either treatment significantly augmented DA synthesis, and by day 15 effects were as great as those observed in adult retinas. At each time point, the magnitude of the drug effect on DA synthesis in the dark was similar to that observed following light exposure. These results suggest that an endogenous GABAergic inout to the DA neurons appears at the same time as the acquisition of the dopaminergic response to light. The effect of bicuculline treatment on DA synthesis in light-exposed animals was also assessed. At 4 and 7 days the drug significantly enhanced DOPA accumulation over that produced by exposure to light alone, but on later days bicuculline exerted no such additive effect. These data imply that early in the maturation of the light response mechanisms other than removal of an inhibitory GABAergic tone may be partially responsible for excitation of the DA neurons.