cssi/SciSciGPT-SciSciNet huggingface dataset:
Technology and labor relations in the construction industry

Conclusions It is clear that a great array of new job titles and a profusion of semiskilled categories of construction work have developed which were not represented by unions when unions established the labor structure that dominated the industry for many years. They have come about because technology has compressed skill requirements away from the extremes and towards the center: fewer craftsmen with highly refined, broadly based skills are needed, but more who have limited or specialized skills are needed, and more who can apply some lesser degree of skill than either, but enough to be able to follow their leads, are also needed. At the same time, there is less need for lift-and-carry work unassisted by mechanical advantage, so there is decreased demand for laborers in the old sense—workers who were allowed to use the tools of no trade.
Challenge of neotropical frugivory: Travel patterns of spider monkeys and bearded sakis

We compared travel patterns of two neotropical frugivores, Ateles paniscus (black spider monkeys) and Chiropotes satanas (bearded sakis), during a 6-month study at Raleighvallen-Voltzberg Nature Reserve in Surinam. Ateles were typically found in small foraging parties that changed in size and composition throughout the day. Chiropotes troops moved from one feeding area to the next, fragmenting "locally" when they entered an area with more than one feeding tree. Chiropotes moved through fewer half-hectare quadrats before encountering a feeding tree, and were more likely to locate multiple trees per quadrat than were Ateles. Several investigators have suggested that fission-fusion travel patterns (sensu Ateles and Pan) have the potential to reduce feeding competition among troop members. We suggest that even slight modifications in the size and composition of foraging parties, such as "local" temporary troop fragmentation, have the same effect, and may be common among frugivorous primates. © 1994 Wiley-Liss, Inc.
Mechanisms of Ischemic Neuroprotection by Acetyl-L-carnitine

Acetyl-L-carnitine is a naturally occurring substance that, when administered at supraphysiologic concentrations, is neuroprotective in several animal models of global and focal cerebral ischemia. Three primary mechanisms of action are supported by neurochemical outcome measures performed with these models and with in vitro models of acute neuronal cell death. The metabolic hypothesis is based on the oxidative metabolism of the acetyl component of acetyl-L-carnitine and is a simple explanation for the reduction in postischemic brain lactate levels and elevation of ATP seen with drug administration. The antioxidant mechanism is supported by reduction of oxidative stress markers, for example, protein oxidation, in both brain tissue and cerebrospinal fluid. The relatively uncharacterized mechanism of inhibiting excitotoxicity could be extremely important in both acute brain injury and chronic neurodegenerative disorders. New experiments performed with primary cultures of rat cortical neurons indicate that the presence of acetyl-L-carnitine significantly inhibits both acute and delayed cell death following exposure to NMDA, an excitotoxic glutamate antagonist. Finally, several other mechanisms of action are possible, including a neurotrophic effect of acetyl-L-carnitine and inhibition of mitochondrial permeability transition. While the multiple potential mechanisms of neuroprotection by acetyl-L-carnitine limit an accurate designation of the most important mode of action, they are compatible with the concept that several brain injury pathways must be inhibited to optimize therapeutic efficacy.
Acute neuroradiologic findings in young children with inflicted or noninflicted traumatic brain injury

Acute CT/MRI findings were examined in a prospective, longitudinal study of 60 children 0–6 years of age hospitalized for moderate to severe traumatic brain injury (TBI). TBI was categorized as either inflicted (n=31) or noninflicted (n=29). Glasgow Coma Scale scores and perinatal history were comparable in both groups. Acute CT/MRI studies were visually inspected by a radiologist blind to group membership. Compared with the noninflicted TBI group, the inflicted TBI group had significantly elevated rates of subdural interhemispheric and convexity hemorrhages as well as signs of pre-existing brain abnormality, including cerebral atrophy, subdural hygroma, and ex vacuo ventriculomegaly. Intraparenchymal hemorrhage, shear injury, and skull fractures were more frequent after noninflicted TBI. Subarachnoid hemorrhage and infarct/edema occurred with comparable frequency in both groups. Characteristic acute neuroimaging findings of inflicted TBI included multiple extraaxial hemorrhages in addition to the mild atrophy, subdural hygromas, and ventriculomegaly that suggest prior brain abnormality.
Lithospheric flexure at fracture zones

Studies attempting to demonstrate that lithospheric flexure occurs across the Pioneer and Mendocino fracture zones, and that the flexural topography is a topographic expression at these fracture zones, are presented. The flexure is modelled and compared with predicted depths with five bathymetric profiles which cross the two fracture zones at different ages. The model uses a thin elastic plate overlying an incompressible fluid half-space, and incorporates a temperature-dependent effective elastic thickness. Several conclusions were derived from this study. First, it is found that no significant slip on the fossil fault planes of the Mendocino and Pioneer fracture zones exists. In addition, the flexural amplitude is determined to increase with age. Finally, it is concluded that there is elastic coupling between the Mendocino and Pioneer fracture zones since the separation is less than a flexural wavelength.
Current microbiological considerations in food preservation

Changes in the composition and properties of certain foods, as well as development of food products to meet consumer demands relating to health, nutrition and convenience lead to concerns about the microbiological safety of such products. Concerns also arise from emergence or recognition of the importance of certain microbial food pathogens or spoilage organisms, as well as from modifications in food processing, handling, storage and preparation procedures. These facts necessitate continuous reevaluation of factors involved in the control of microbial growth in order to preserve foods and maintain their quality and safety.
Interactions with the Bifunctional Interface of the Transcriptional Coactivator DCoH1 Are Kinetically Regulated

Abstract Pterin-4a-carbinolamine dehydratase (PCD) is a highly conserved enzyme that evolved a second, unrelated function in mammals, as a transcriptional coactivator. As a coactivator, PCD is known as DCoH or dimerization cofactor of the transcription factor HNF-1. These two activities are associated with a change in oligomeric state: from two dimers interacting as an enzyme in the cytoplasm to a dimer interacting with a dimer of HNF-1 in the nucleus. The same interface of DCoH forms both complexes. To determine how DCoH partitions between its two functions, we studied the folding and stability of the DCoH homotetramer. We show that the DCoH1 homotetramer is kinetically trapped, meaning once it forms it will not dissociate to interact with HNF-1. In contrast, DCoH2, a paralog of DCoH1, unfolds within hours. A simple mutation in the interface of DCoH2 from Ser-51 to Thr, as found in DCoH1, increases the kinetic stability by 9 orders of magnitude, to τ½ ∼2 million years. This suggests that the DCoH1·HNF-1 complex must co-fold to interact. We conclude that simple mutations can dramatically affect the dissociation kinetics of a complex. Residue 51 represents a “kinetic hot spot” instead of a “thermodynamic hot spot.” Kinetic regulation allows PCD to adopt two distinct functions. Mutations in DCoH1 associated with diabetes affect both functions of DCoH1, perhaps by disrupting the balance between the two DCoH complexes.
Structural Basis of Streptococcus pyogenes Immunity to its NAD+ Glycohydrolase Toxin

Summary The virulence of Gram-positive bacteria is enhanced by toxins like the Streptococcus pyogenes β-NAD + glycohydrolase known as SPN. SPN-producing strains of S . pyogenes additionally express the protein i mmunity f actor for S PN (IFS), which forms an inhibitory complex with SPN. We have determined crystal structures of the SPN-IFS complex and IFS alone, revealing that SPN is structurally related to ADP-ribosyl transferases but lacks the canonical binding site for protein substrates. SPN is instead a highly efficient glycohydrolase with the potential to deplete cellular levels of β-NAD + . The protective effect of IFS involves an extensive interaction with the SPN active site that blocks access to β-NAD + . The conformation of IFS changes upon binding to SPN, with repacking of an extended C-terminal α helix into a compact shape. IFS is an attractive target for the development of novel bacteriocidal compounds functioning by blocking the bacterium's self-immunity to the SPN toxin.
Suppression of auger processes in confined structures.

We explore how the size and shape of the microscopic confinement potential affects the nonradiative Auger decay rate of confined carriers. Calculations conducted in the two-band, effective mass Kane model unambiguously show that smoothing out the confinement potential could reduce the rate by more than 3 orders of magnitude relative to the rate in structures with abruptly terminating boundaries. As the confinement potential width is increased, the calculated rate decreases overall, exhibiting very deep minima at regular widths. Such minima suggest that nanocrystals of “magic sizes” can exist for which nonradiative Auger processes are strongly suppressed.
Connecting Descriptive and Substantive Representation: An Analysis of Sex Differences in Cosponsorship Activity

Women-and-politics research emphasizes the importance of social identity as a determinant of legislative behavior, yet congressional scholars largely ignore identity and focus on the impact of constituency, party, and institutional factors. To examine the link between descriptive and substantive representation, I utilize an original database of cosponsorship activity in the 103d and 104th Congresses that encompasses five social welfare issues that reflect the gender gap in the mass public. I find that the policy preferences of elites do reflect gender differences in the mass public and voter expectations concerning the policy expertise of women candidates. These differences are constrained by changes in the political and institutional contexts since women increase their activity on social welfare issues when they gain access to strategic positions of power, particularly majority party status, to a greater extent than do similarly situated men.
General characteristics and viral susceptibility of bovine embryonic tissue cultures.

Abstract Preparation of serial passage cultures of bovine lung, muscle, and kidney tissues is described. These have been tested for their susceptibility to a large number of viruses. The agents of vaccinia and vesicular stomatitis readily multiplied in such tissues. Adenoviruses, herpes, and B virus could be propagated for two to four passages but with a progressive loss of infectivity. Bovine tissue cultures did not support the growth of twenty-seven other agents.
Synthesis and characterization of size-controlled vanadium dioxide nanocrystals in a fused silica matrix

Vanadium dioxide single-crystal precipitates with controlled particle sizes were produced in an amorphous, fused SiO2 host by the stoichiometric coimplantation of vanadium and oxygen ions and subsequent thermal processing. The effects of the vanadium dioxide nanocrystal size, nanocrystal morphology, and particle/host interactions on the VO2 semiconductor-to-metal phase transition were characterized. VO2 nanoparticles embedded in amorphous SiO2 exhibit a sharp phase transition with a hysteresis that is up to 50 °C in width—one of the largest values ever reported for this transition. The relative decrease in the optical transmission in the near-infrared region in going from the semiconducting to the metallic phase of VO2 ranges from 20% to 35%. Both the hysteresis width and the transition temperature are correlated with the size of the precipitates. Doping the embedded VO2 particles with ions such as titanium alters the characteristics of the phase transition, pointing the way to control the hysteresis beha...
Extending Service-Oriented Architectures to the tactical edge

Service Oriented Architectures allow for seamless integration of heterogeneous systems and extensive service reuse; characteristics that led to a wide adoption of this paradigm in the enterprise and military environment. While SoAs are currently deployed in tactical environments mainly at higher-echelon levels, it is necessary to allow for the exchange of information all the way down to the edge nodes deployed on the ground and back. Because most SoAs implementations were designed to work on reliable infrastructure networks, porting SoAs to the tactical environment requires a complete redesign of the protocol stack to support unreliable, transiently disconnected networks. In this paper, we present our approach to integrate the U.S. Marine Corps's Marine Command and Control Systems and Applications SoA (MC2SA SoA) with DisServicePro, a middleware that supports proactive dissemination and information on demand in tactical edge networks.
Singlet Exciton Fission and Tri plet-Tri plet Exciton Fusion in Crystalline Tet racene

Abstract The dominant radiationles decay channel in crystalline tetracene at 300 °K is a fission of an excited singlet into two triplet excitons with a rate constant γS = 1.5 × 10−12 ± 5% cm3 -sec−...
Molecular biology as it relates to digital image processing

Biological research has been placing increased attention upon the determination of the atomic structures of large molecules. These have generally been proteins and especially enzymes whose molecular weights range up to 50,000. Tremendous efforts to infer functional configurations of active enzyme sites have been expended by organic chemists. But total atomic configuration has been performed exclusively by the digital computer using the methods of x-ray crystallography. The sequences of the amino acids in these enzymes have been determined by organic chemists. The information is then used by the crystallographer to infer initial estimates about the actual geometrical configuration, which the crystallographic data eventually confirm. Several of these molecules and their functions will be described.
An algorithm for the identifiable parameter combinations of the general mammillary compartmental model

Abstract Mammillary compartmental models are not uniquely identifiable except in special cases where parameter subsets of rate constants have known values. However, even for the most general n -pool mammillary model, an intrinsic set of parameter combinations is identifiable. An explicit algorithm for computing the uniquely identifiable sums and products of unidentifiable parameters for this class of models is developed for the most practical experimental conditions, input into and output from the central pool. Also, all steady state unidirectional mass fluxes from noncentral pools to the central pool (products of pool masses Q i and fractional transport rates k 1 i ) are shown to be always uniquely identifiable, even when the Q i and k 1 i are not, and the lower bounds are the same and the upper bounds are the same for all mass fluxes to the invironment.
Effect of lateral positions on tissue oxygenation in the critically ill.

Abstract Objective: The purpose of this study was to assess the effect of lateral positions on tissue oxygenation in critically ill patients. Design: The study design was prospective and quasi-experimental, and we used a convenience sample with random assignment. Setting: The study took place in the intensive care unit and the cardiac intensive care unit of a 450-bed medical center in the northwestern United States. Patients: The sample included 12 adult patients with indwelling pulmonary artery and radial arterial catheters who were receiving mechanical ventilation and who met the criteria of “critical illness” by having impaired arterial oxygenation (PaO 2 ≤ 70 mm Hg) and/or cardiac index ≤ 2.0 L/min/m 2 . Outcome Measures: The outcome measures were dependent variables reflecting oxygen delivery including heart rate, cardiac output, arterial oxygen content (CaO 2 ) and oxygen consumption, and the adequacy of tissue oxygenation (serum lactate). Intervention: Each patient was passively turned to each of the three positions (right and left 45° lateral and supine) according to a computer-generated, randomized positioning sequence. Dependent variables were measured 15 minutes after each position change. No changes in ventilator settings or vasoactive drugs occurred during data collection. Results: Analysis of variance for repeated measures was used in the data analysis. Post hoc analysis determined an effect size of 0.558 and power of 0.80 at an α level of.05. No statistically significant differences caused by position were found in mean CaO 2 , cardiac output, heart rate, respiratory rate, PaO 2 , SaO 2 , or lactate level. Pearson correlation analysis found no significant relationships between the primary variables reflecting oxygen delivery (cardiac output and CaO 2 ) and serum lactate levels. Conclusions: These findings suggest that lateral positioning of critically ill patients who are hypoxemic or have low cardiac output does not further endanger tissue oxygenation. Evaluation of individual patient responses to position changes in the clinical setting is encouraged until further studies using more heterogenous populations can provide more definitive guidance.(Heart Lung ® 2001;30:269-76.)
Modeling Disaster Response Planning

Most emergency management officials work in small organizations with limited resources. Formal disaster response planning is often given a back seat to other activities. If more tools were available to assist in the planning process the results would be better. This paper presents a model that can be used by emergency management officials to assist in the preparation of their disaster response and mitigation plans. The model builds on a geographic information system frame, giving a visual presentation to its users. The necessary databases are described and responsibilities assigned. Included is an example of how the model would be used and an assessment of it by emergency management officials.
What Counts as Software Process? Negotiating the Boundary of Software Work Through Artifacts and Conversation

In software development, there is an interplay between Software Process models and Software Process enactments. The former tends to be abstract descriptions or plans. The latter tends to be specific instantiations of some ideal procedure. In this paper, we examine the role of work artifacts and conversations in negotiating between prescriptions from a model and the contingencies that arise in an enactment. A qualitative field study at two Agile software development companies was conducted to investigate the role of artifacts in the software development work and the relationship between these artifacts and the Software Process. Documentation of software requirements is a major concern among software developers and software researchers. Agile software development denotes a different relationship to documentation, one that warrants investigation. Empirical findings are presented which suggest a new understanding of the relationship between artifacts and Software Process. The paper argues that Software Process is a generative system, which participants called "The Conversation," that emerges out of the interplay between Software Process models and Software Process enactments.
Parallel On-Line and In-Class Sections of "Writing for the Professions": A Practical Experiment

This paper describes experiences with on-line and in-class sections of a writing-intensive course, including a collaborative library literacy unit. It reports on a mid-semester software change and offers a comparative outcome assessment. The authors, whose experience reflects that of other on-line writing instructors, suggest that on-line students may self-select into an informal “elite” and make recommendations concerning course design, class size, and software needs.
The self-help movement : review of the past decade of research

In the past decade the self-help movement has attracted much attention. Many believe it will continue as a major vehicle for mental health in the coming years. This article reviews the literature on self-help groups over the past 10 years. Emphasis is given to literature that examines professional roles with self-help groups, studies of self-help group processes, and outcome evaluations. Suggestions for social work practice and future research are proposed.
A comparison theorem for cooperative control of nonlinear systems

Asymptotic cooperative stability is studied in the paper, and explicit conditions are found for heterogeneous nonlinear systems to reach a consensus. Specifically, a new comparison theorem is proposed for concluding both cooperative stability and Lyapunov stability, and it is in terms of vector nonlinear differential inequalities (on Lyapunov function components). It is unique that the proposed result admits both heterogeneous dynamics of nonlinear systems and intermittent unpredictable changes in their associated sensing/communication network. Its proof is done using a combination of Lyapunov argument (in terms of the Lyapunov function components) and topology- dependent argument (in terms of structural properties of reducible matrices). Consequently, the proposed result does not impose any of the following assumptions required in the existing results: the knowledge of a successful Lyapunov function, system dynamics being convex, nonsmooth analysis, fixed or certain types of communication patterns, quasi- monotone property on differential inequalities. If the systems under consideration are all linear, the theorem reduces to the necessary and sufficient condition of cooperative controllability obtained using the matrix-theoretical approach, and the inequalities become equalities. For nonlinear systems, the proposed cooperative stability conditions are straightforward to verify. Several types of nonlinear systems are used as examples to illustrate application potentials of the comparison theorem in both cooperative stability analysis and cooperative control design.
The expulsion of OH˙ from the [M C2H4]+˙ ion from ethyl benzoate: Ring‐deuterated compounds

Mass spectra and ion kinetic energy (IKE) spectra of o-, m- and p-d1 ethyl benzoates have given further information on the loss of OH˙ and OD˙ from the [M C2H4]+˙ ions. The ‘metastable peaks’ in the mass spectra give information on fragmentations in the field-free region following the electric sector; the IKE spectra give information on fragmentations in the field-free region preceding this sector. Transfer of hydrogen and deuterium from the ortho-positions on the ring to the carboxyl group can occur, but scrambling of ring hydrogens does not take place. A sample of o-d1 benzoic acid was also examined and confirmed that similar transfer reactions occur in this compound too.
Sonority constraints on syllable structure

One of the crucial ways in which prosodic structure governs the distribution of segments is in terms of sonority. By taking into account what is known′ as the sonority of segments, their arrangement within the syllable follows a clear pattern: the most sonorous segment occupies the peak position, while the less sonorous ones occur towards the margins, as observed in a wide range of literature (Jespersen 1904; Saussure 1916; Zwicky 1972; Hooper 1976; Kiparsky 1979, 1981; Lowenstamm 1981; Steriade 1982; Selkirk 1984; Clements 1990). This specific arrangement of segments within the syllable has been attributed in the previous literature to the principle of sonority sequencing, which relegates segments low in sonority towards syllable margins (see Hooper 1976; Kiparsky 1979, 1981; Steriade 1982; Selkirk 1984; Levin 1985; Clements 1990).
The relationship between Luce's Choice Axiom, Thurstone's Theory of Comparative Judgment, and the double exponential distribution

Abstract Holman and Marley have shown that Thurstone's Case V model becomes equivalent to the Choice Axiom if its discriminal processes are assumed to be independent double exponential random variables instead of normal ones. It is shown here that for pair comparisons, this representation is not unique; other discriminal process distributions (specifiable only in terms of their characteristic functions) also yield a model equivalent to the Choice Axiom. However, none of these models is equivalent to the Choice Axiom for triple comparisons: There the double exponential representation is unique. It is also shown that within the framework of Thurstone's theory, the double exponential distribution, and hence the Choice Axiom, is implied by a weaker assumption, called “invariance under uniform expansions of the choice set.”
Improving the dependability of wireless networks using design techniques

Network dependability is an important issue for service providers, vendors, and users. Although some work has been done in wireline networks for improving reliability, availability, and survivability aspects of network dependability, very little work has been done to do the same for wireless networks. As wireless networks are more likely to have dependability problems, we believe that some work is necessary to address the dependability issues in wireless networks. We propose an integrated approach using design changes and fault-tolerance to improve the dependability of wireless networks. More specifically, we present several architectures to improve the dependability of wireless networks, a simulation model for evaluating one or more of these architectures, and detailed performance results. The results show that significant improvements are possible in the wireless dependability attributes of the current and emerging wireless networks. We have also obtained results for fault-tolerant architectures of varying size, showing substantial improvements in both network availability and survivability attributes.
Developmental Relationships between Reading Comprehension and Deductive Reasoning.

Summary A reading comprehension test and a deductive reasoning test were administered to 720 students in Grades 5 through 8. Each item on the deductive reasoning test consisted of a prose passage containing the premises of a basic logical rule and a question that required students to evaluate a conclusion drawn from these premises. Students' scores on the deductive reasoning test were analyzed according to grade level, level of reading comprehension, and type of logical rule. Developmental gains in deductive reasoning abilities were limited to students with high reading comprehension; and interesting variations were found in the order of dominance of the logical rules at each grade level and for each reading comprehension group.
A Simple Technique for Retrograde Cerebral Perfusion During Circulatory Arrest

We describe a simple and safe technique for achieving retrograde cerebral perfusion via a small coronary sinus type catheter placed in the superior vena cava. This method is especially useful when the need for circulatory arrest is first recognized intraoperatively and a single two-stage venous cannula has already been placed for cardiopulmonary bypass. The advantages of this technique over other currently employed methods for retrograde cerebral perfusion are discussed.
An Efficient Type- and Control-Flow Analysis for System F

At IFL'12, we presented a novel monovariant flow analysis for System F (with recursion) that yields both type-flow and control-flow information. [5] The type-flow information approximates the type expressions that may instantiate type variables and the control-flow information approximates the λ- and Λ-expressions that may be bound to variables. Furthermore, the two flows are mutually beneficial: control flow determines which Λ-expressions may be applied to which type expressions (and, hence, which type expressions may instantiate which type variables), while type flow filters the λ- and Λ-expressions that may be bound to variables (by rejecting expressions with static types that are incompatible with the static type of the variable under the type flow).Using a specification-based formulation of the type- and control-flow analysis, we proved the analysis to be sound, decidable, and computable. Unfortunately, naively implementing the analysis using a standard least fixed-point iteration yields an O(n13) algorithm.In this work, we give an alternative flow-graph-based formulation of the type- and control-flow analysis. We prove that the flow-graph-based formulation induces solutions satisfying the specification-based formulation and, hence, that the flow-graph-based formulation of the analysis is sound. We give a direct algorithm implementing the flow-graph-based formulation and demonstrate that it is O(n4). By distinguishing the size l of expressions in the program from the size m of types in the program and performing an amortized complexity analysis, we further demonstrate that the algorithm is O(l3 + m4).
Transmitter-Oriented Code Assignment for Multihop Packet Radio

Quasi-orthogonal codes are assigned to transmitters in a packet radio network such that interference caused by hidden terminals is eliminated. In addition, a handshaking protocol permits random access between nodes. Simple mathematical models and simulation indicate a potential throughput advantage over slotted ALOHA and CSMA.
Variation in the chemistry of the TiO2-mediated degradation of hydroxy- and methoxybenzenes: electron transfer and HOads initiated chemistry

The early degradation product distributions from TiO2-mediated photocatalytic degradations of a series of multiply hydroxylated benzenes and their methoxylated analogs is reported. The methoxylated compounds show a distinct trend away from ring-opening reactions that are attributed to electron transfer chemistry towards hydroxylations and demethylations that are attributed to hydroxyl-type chemistry. The initial rates of the reactions suggest that this is not simply due to the availability of the extra carbon sites. It is instead hypothesized that the compounds with hydroxyl groups are bound to the TiO2 in such a way as to facilitate electron transfer and its subsequent chemistry. Addition of isopropyl alcohol to the degradations slows the degradations of the methoxylated compounds more than it does the hydroxylated compounds and particularly inhibits the demethylation and hydroxylation reactions. It is suggested that the question of whether an organic substrate must be bound to the photocatalyst at the time of excitation may be dependent on the type of chemistry being observed.
Induced Regeneration of Skin and Peripheral Nerves

Acute or chronic injury to an organ is followed by a spontaneous healing process. Injury to the mammalian fetus is reversible during early stages of gestation; the spontaneous wound response is capable of restoring the structure and function of the original organ (regeneration). In contrast, the unimpaired response of adults to severe injury is an irreversible process leading to closure of the injured site by contraction and formation of scar, a nonphysiological tissue (repair). The consequences of irreversible healing at the organ scale are far reaching: they often result in an essentially nonfunctional organ.
Sex Differences in Exploration: Toward a Theory of Exploration

Studies relating sex differences in the exploration of rats to the degree of deprivation are reviewed. It is concluded that females explore more when satiated than when deprived whereas males explore more when deprived than when satiated. A theory of exploration is described in which the fear aroused by novel stimuli is related to the probability of approach by the animal to these stimuli by a U-shaped function. This theory is used to account for the sex differences in exploration.
Electro-Optical Properties and Interfacial Charges in Polymer-Dispersed Liquid Crystal Devices

Polymer-dispersed liquid crystal (PDLC) is a composite material that consists of sub micron-size droplets of liquid crystalline (lc) material dispersed in a polymer matrix. A device is usually assembled by sandwiching PDLC between ITO-coated glass plates. The electro optical properties of such a device can be controlled by the application of electric fields; the device acts as a “switch” for the transmission of light. The transmission of light through the device can be controlled between almost zero and 100% by applying ac electric fields. The dielectric properties of the lc and polymer, shape and size distribution of the lc droplets in the PDLC, amplitude and frequency of the applied electric field are among the important parameters for optimizing the performance of such a device. We have investigated the optical properties of PDLC devices fabricated by using several different phase-separation techniques and different lc/polymer materials. We present results for the switching characteristics of these devices as functions of applied electric fields and the size-distribution of the lc droplets. We also present results that reinforce the influence of the interfacial charges on the optical properties of the PDLC devices.
Simulation-free estimation of reaction propensities in cellular reactions and gene signaling networks

Abstract Classical reaction kinetics based on deterministic rates laws are not valid for the description of cellular events in which the small number of molecules introduces stochasticity with discrete instead of continuous state transitions. Stochastic models are suitable for simulating transcriptional and translational events inside biological cells, but are impractical for solving inverse problems, which aim to estimate unknown reaction propensities from experimental observations. We introduce a new mathematical framework of Ito stochastic differential equations for the modeling of discrete cellular events and the robust and consistent parameter estimation of cellular dynamics where classical reaction kinetics is invalid. The results supported by case studies on gene expression in B. subtilis cells and viral gene transcription and translation inside non-lytic viral cells demonstrate that the proposed methodology performs as reliable as the gold standard Gillespie algorithm for simulating cellular events. More importantly, the new Ito process framework is ideal for estimating unknown reaction propensities from data as readily as in deterministic parameter estimation by using the novel ‘SPE – simulation free parameter estimation’ approach. Also, the computation time for the stochastic differential equation models is significantly low when compared to discrete event simulations.
Podiatric Issues in Older Adults

A common debilitating condition in older adults which impact their level of independence involve conditions interfering with the ability to walk freely. Podiatric conditions develop over decades of...
Optimizing a custom tiling microarray for low input detection and identification of unamplified virus targets

Viruses are major pathogens causing foodborne illnesses and are often present at low levels in foods, thus requiring sensitive techniques for their detection in contaminated foods. The lack of efficient culture methods for many foodborne viruses and the potential for multi-species viral contamination have driven investigation toward non-amplification based methods for virus detection and identification. A custom DNA microarray (FDA_EVIR) was assessed for its sensitivity in the detection and identification of low-input virus targets, human hepatitis A virus, norovirus, and coxsackievirus, individually and in combination. Modifications to sample processing were made to accommodate low input levels of unamplified virus targets, which included addition of carrier cDNA, RNase treatment, and optimization of DNase I-mediated target fragmentation. Amplification-free detection and identification of foodborne viruses were achieved in the range of 250–500 copies of virus RNA. Alternative data analysis methods were employed to distinguish the genotypes of the viruses particularly at lower levels of target input and the single probe-based analysis approach made it possible to identify a minority species in a multi-virus complex. The oligonucleotide array is shown to be a promising platform to detect foodborne viruses at low levels close to what are anticipated in food or environmental samples.
Pediatric salivary gland neoplasms: The M. D. Anderson Cancer Center experience

20006 Background: Epithelial salivary gland neoplasms (ESGN) are uncommon tumors that mainly occur in adults, only 5 percent of ESGNs occur in children. Data regarding differences in clinical presentation and biologic behavior of these tumors between adult and pediatric patients remain unclear. There is less data concerning the role of radiation therapy in the treatment of ESGNs in pediatric patients. Methods: Retrospective review of medical records of patients presenting under age 18 years from January 1988 to August 2006. Results: 45 patients were evaluable. 26 patients were female. Median age at diagnosis was 14.7 years. Mucoepidermoid carcinoma (MEC) was seen in 22 cases (49%), acinic cell carcinoma 10 cases (22%), adenocystic carcinoma (ACC) 8 cases, and pleomorphic adenoma (PA) 5 cases. The parotid area was the most common involved site (25/45; 56%) with MEC and acinic cell noted in 80% of parotid cases. 76% of MEC cases (16/21) were grade 2 or 3 tumors. Initial complete resection was achieved in 20...
Association of activated NF-kB, altered cyclin D1 and poor outcome in esophageal adenocarcinoma

Proc Amer Assoc Cancer Res, Volume 46, 2005 2334 The dramatic increased incidence and poor survival rates of esophageal adenocarcinoma (EAC) underscore the need for novel therapeutic targets. Cyclin D1 (CD1) altered protein expression has been proposed as an early predictor for malignant transformation in EAC. We previously reported that cyclin D1 A870G polymorphism, which influences CD1 protein turnover, was associated with increased CD1 levels, early onset and poor outcome in EAC. However, the upstream mechanisms of CD1 transcriptional activation in EAC are still unknown. To examine the potential role of the transcription factor NF-kappaB (NF-κB) as an upstream regulator of CD1, we compared the correlation of activated NF-κB (nuclear localization), CD1 protein expression and clinical outcome in 66 patients undergoing surgical resection for EAC. All pathological specimens contained EAC and normal squamous mucosa; 34/66 cases contained Barrett’s premalignant lesions. NF-κB positivity was found in 48/66 (72.7%) EAC, associated with concomitant CD1 overexpression in 41/48 (85.4%) cases. CD1 was overexpressed in only 1/18 NF-κB negative EAC. While NF-κB/CD1 positive and negative EAC groups showed similar frequencies of soft tissue and lymph nodes invasion [20/41 (48.7%) NF-kB/CD1 positive vs 16/25 (64%) NF-κB/CD1 negative, p=1.0], the NF-κB/CD1 positive group showed increased perineural/vascular invasion [14/41 (34%) NF-κB/CD1 positive vs 2/25 (8%) NF-κB/CD1 negative, p=.01]. The NF-κB/CD1 positive group also developed more recurrences and distant metastasis [23/41 (56%) NF-κB vs 7/25 (28%) NF-κB/CD1 negative, p=.040] and had a shortened survival ([fig.][1]). NF-κB and CD1 were concomitantly positive in 28/34 (82.3%) adjacent Barrett’s premalignant epithelia. Interestinlgy, activated NF-kB and cyclin D1 overexpression were spatially colocalized in EAC and the adjacent premalignant lesions. These results suggest that NF-kB may be involved in the transcriptional upregulation of CD1 during the progression to EAC, and may represents a novel target for the prevention and treatment of EAC. (UTMDACC Esophageal MRP, EDRN 86390) ![Figure][2] [1]: #F1 [2]: pending:yes
The Child Dental Control Assessment (CDCA) in youth: reliability, validity and cross-cultural differences.

AIM The Child Dental Control Assessment (CDCA) measures children's preferred control strategies in the dental situation. Three studies are reported, assessing aspects of this instrument in youths from the USA, Japan and Australia. In particular, measurements were made as to the reliability and validity of this instrument in this age group in the three cultures, as well as comparing some results across cultures. STUDY DESIGN These studies used a questionnaire design. METHODS Questionnaires (including the CDCA and other measures) were given to youths aged 11-15 in the three cultures. In one culture, youths received the questionnaire twice, to compute test-retest reliability. RESULTS The measure's reliability and validity were similar to those of other measures. The CDCA behaves similarly to the Revised Iowa Dental Control Index (R-IDCI). Youths in all three cultures showed similar responses, although the Japanese were less likely to endorse items. STATISTICS Internal reliability of the scale ranged from 0.74 to 0.85. Test- retest reliability was 0.74. Participants in the High Desire/Low Predicted classification on the R-IDCI scored higher on the CDCA (t (73) = 2.9, p < .01). In the Japanese and Australian samples the correlation between CDCA and dental fear was 0.29-0.33 (p < .001). The Australian and USA samples scored significantly higher than the Japanese sample (overall F(2,1544) = 383.98, p < .001, followed by Tukey's HSD, p < .001). CONCLUSIONS These results provide evidence for the reliability and validity of the CDCA in youth. It appears to measure the discrepancy between Desired and Predicted Control identified in the Revised Iowa Dental Control Index (R-IDCI). Responses of the youth in all three cultures were similar, indicating common dental control preferences for individuals of this age. However, consistent with cultural values, Japanese youth were less likely to endorse the control strategies. These results underline the need to develop culturally-specific, as well as situationally-specific control measures.
Sexually Transmitted Diseases of the Vulva

Sexually transmitted disorders may present on the vulva as ulcers, rashes, edema, adenopathy, or pruritus. Clinical and laboratory skills are needed to distinguish one from another so that the proper treatment is selected and further venereal spread is prevented.
Fluorinated Pickering Emulsions with Nonadsorbing Interfaces for Droplet-based Enzymatic Assays

This work describes the use of fluorinated Pickering emulsions with nonadsorbing interfaces in droplet-based enzymatic assays. State-of-the-art droplet assays have relied on one type of surfactants consisting of perfluorinated polyether and polyethylene glycol (PFPE-PEG). These surfactants are known to have limitations including the tedious synthesis and interdrop molecular transport which leads to the cross-contamination of droplet contents. Previously we have shown that replacing surfactants with nanoparticles as droplet stabilizers mitigate interdrop transport of small molecules. The nonspecific adsorption of enzymes on nanoparticle surface, however, could cause structural changes in enzymes and consequently the loss of enzymatic activity. To overcome such challenge, we render nanoparticle surface nonadsorbing to enzymes by in situ adsorption of polyethylene glycol (PEG) on particle surfaces. We show that enzyme activities are preserved in droplets stabilized by PEG-adsorbed nanoparticles, and are comparable with those in drops stabilized by PFPE-PEG surfactants. In addition, our nonadsorbing Pickering emulsions successfully prevent interdrop molecular transport, thereby maintaining the accuracy of droplet assays. The particles are also simple and economical to synthesize. The PEG-adsorbed nanoparticles described in this work are thus a competitive alternative to the current surfactant system, and can potentially enable new droplet-based biochemical assays.
In Reply: Alcoholic hepatitis: An important consideration.

Readers comment on enterovirus D-68 (January 2015), eosinophilic esophagitis (February 2015), the Patient Protection and Affordable Care Act (February 2015), and alcoholic hepatitis (March 2015).
Effect of compensatory growth on regulation of growth and lactation: response of dairy heifers to a stair-step growth pattern.

The primary objective of this study was to improve the productive efficiency of growth via optimal use of both high fiber-low quality and high energy-high protein feeds in diets for growing dairy cattle. Twenty Holstein heifers were randomly assigned to either a control or treatment group. The control diet met the National Research Council (NRC) requirement for .45 kg/d gain, with heifers calving at 24 to 26 mo of age. The test groups were fed according to a 5-2-5-2 mo schedule in which the nutrient density was alternately 15% below or 40% above the NRC requirement. Results showed that the heifers on the test dietary regimen (compensatory growth) gained more and consumed less, resulting in significantly improved efficiency of growth (body gain/dry matter intake X 100), energy (body gain X 1,000/metabolizable energy (ME) intake) and protein utilization (body gain/protein intake X 100) in comparison to control animals (13.0 vs 7.3%; 57.9 vs 32.6 g/Mcal ME; 96.5 vs 54.2%, respectively). Marked changes in average concentration of urea-N, glucose, triglycerides, cholesterol and lecithin cholesterol acyltransferase activity in blood were seen for test heifers during the stair-step growth phase (i.e., alternating maintenance and compensatory). Evidence from this experiment suggests that the phased growth (stair-step) system offers a simple, practical and cost-effective method for raising dairy heifers.
A Question of Cosmology

1. The electric bulb suspended over my head has the power to obliterate the divine sublimity of the starry heavens above! Who would ever have imagined it! But the denizens of our cities can bear witness to this unfortunate fact. Our technology in a form seemingly so insignificant can blind our eyes and even dull our minds to the magnificence of nature and perhaps to nature herself. When combined with myriad others, this puny appliance can pretend to vie with the celestial bodies and their powers, almost as the Titans of old strove against the ancient gods and their authority. Nevertheless, I do not believe that we face an environmental crisis. We do have environmental problems aplenty, I admit. But our crisis is a crisis of the human spirit. We fail to grasp what I would call the mysterious divinity of life and of existence itself. If we do get an occasional glimpse of it, we neglect to incorporate this divinity of nature into our daily thoughts and lives. As a consequence, we live lives empty and lonely in isolation not only from nature herself but also from one another and from our own selves. I concede that we admire nature, particularly when we view her as pristine and untrammelled. We have enshrined national parks and wilderness areas in her name. We take sojourns into these natural sanctuaries on holidays, weekends, and vacations.