cssi/SciSciGPT-SciSciNet huggingface dataset:
Capturing Spontaneous Membrane Insertion and Membrane-Induced Conformational Changes of Talin at an Atomic Resolution

Integrins are a diverse set of proteins that play a central role in complex biological processes, such as tumor metastasis and thrombus formation. The integrin heterodimer is often expressed in a low-affinity, inactive state, relying on specific cytoplasmic or extracellular signals for its activation. The cytoskeletal-associated protein talin constitutes one of the major activation pathways of integrin through a membrane-mediated mechanism. While the involvement of activated, membrane-bound talin in this process is well established, atomic details of membrane binding of talin and of talin-dependent integrin activation have been lacking. Using our novel, highly mobile membrane mimetic simulation system, we have successfully captured complete insertion of the talin head domain (THD) in a phosphatidylserine membrane in three independent unbiased simulations, revealing key molecular events involved in the process. The THD is initially recruited to the membrane via the documented membrane orientation patch (MOP), consisting of a large number of positively charged residues. Electrostatic potential calculations revealed THD to be highly polarized, providing a potential mechanism explaining how the protein is aligns for optimal encounter with the membrane. We also observe a large, membrane-induced interdomain conformational change (>2.5 nm), which brings the F3 subdomain into contact with the anionic membrane via residues K325, N326, and K327. This result explains how F2 and F3 subdomains can simultaneously bind the membrane, a biochemically established aspect that could not be explained by the crystal structure. Moreover, we characterize a phenylalanine-rich region as the hydrophobic membrane anchor, consisting mainly of F261 and F283, which is released through the snorkeling motion of a few critical lysine residues within the membrane. Although such an anchor has been hypothesized to exist, none had been identified prior to this study.
Climate Sensitivity from Fluctuation Dissipation: Some Simple Model Tests

Abstract Leith has suggested that climatic response to change in external forcing parameters of the climate system may be estimated via the fluctuation-dissipation theorem (FDT). The method, which uses the natural fluctuations of the atmosphere to probe its dynamics, is tested here using a twenty-variable truncation model of the barotropic vorticity equation. Dissipative terms are added to the equations, so that the model is pushed away from the region where it is expected to satisfy the FDT. It is found that, even though the FDT is no longer satisfied in every detail, the FDT continues to provide an excellent estimate of the climatic sensitivity of the model.
Antarctic Bottom Water production and export by tides in the Ross Sea

[1] Current measurements in the western Ross Sea show that Antarctic Bottom Water is produced at the outer edge of the Continental Shelf by tidal stirring of Antarctic Surface Water, Circumpolar Deep Water and Shelf Water. Current amplitudes during spring tides are greater than 1 m/s, sufficient to carry Circumpolar Deep Water onto the shelf from offshore and stir at least the lower portion of the water column to a nearly homogeneous mixture. The Antarctic Bottom Water produced every day during spring tides does not appear to have a seasonal signal. Its export rate is estimated to be 1.95 ± 1.85 × 10 6 m 3 /s.
Telephone therapy: An alternative to isolation

While a fair amount has been written on the use of the telephone for crisis intervention and management of medical and psychosocial problems, little has been written about the telephone as the primary modality for ongoing therapy. This paper presents the author's experience in providing weekly telephone therapy for two women for over one and one half years. Questions related to the meaning of the telephone therapy for each of the clients and the social worker are discussed. It is concluded that the creative use of the telephone may make supportive therapy possible for some clients who would not otherwise pursue therapy.
Micro- and Nanoscale Characterization of Effect of Interfacial Transition Zone on Tensile Creep of Ultra-High-Performance Concrete:

Ultra-high-performance concretes (UHPCs) are nano- to microstructurally optimized construction materials whose use presents significant opportunities for improving the performance of prestressed bridge girders. In UHPC girders, transverse shear reinforcement may be eliminated because of the high tensile strength of the material achieved through the use of short dispersed steel fibers as part of the mix. Use of the concrete's tensile strength requires that the long-term tensile performance be understood to avoid brittle shear failure in service. The scope of the present study was characterization of the tensile creep of UHPCs under different thermal treatment regimens, with complementary assessment of the underlying mechanisms by characterization by nanoindentation and scanning electron microscopy. In this study, tensile-creep tests were conducted for a period of 1 year with UHPCs subjected to three different moist thermal curing regimes (i.e., early curing at 90°C, early curing at 60°C, and curing at 23°C...
Email Tandem Exchanges as a Tool for Authentic Cultural Learning

This paper presents the description of an email Tandem exchange project conducted between 94 intermediate-level students 47 pairs from Columbia University/Barnard College in New York and Universidad Autonoma de Madrid in Spain during the Fall Semester 2010. There were several goals to this project: to help improve students' writing skills; to encourage them to learn about culture through authentic understood as 'direct contact with a native speaker' and real exposure to the target language; to foster progress in their use of the target languages through peer-to-peer corrections; and to take an active part in their own learning through self-assessment. Based on students' opinions, this project had a very positive impact in the way they viewed the foreign/target culture on both sides of the Atlantic. It also helped them enhance their written proficiency and acquire a new lexical mastery that would have been impossible through the limited and less-real scope of the classroom.
Applications of Sound Intensity Measurements to Gas Turbine Engineering

Recent advances in signal processing techniques have made the measurement of sound intensity a practical reality. The newly developed sound intensity meters can indicate both the magnitude and direction of sound. This is a major advantage over the traditional sound level meter which does not have such directional sensitivity. Sound intensity meters can, therefore, make accurate measurements under adverse conditions, such as onshore or offshore, where sound level meters may be unsuitable.This makes the detailed assessment of the sound power output of a gas turbine package, operating in the field, practicable. Individual components of a gas turbine train can be evaluated so that the dominant noise sources can be identified, thereby providing more cost effective solutions to onshore and offshore installations.This paper describes briefly the concepts of sound intensity, the current state of standards and some aspects of measurement technique. Case histories of the use of sound intensity instrumentation in a variety of situations, relevant to gas turbine engineering, will be described. This will include laboratory and field based investigations.Copyright © 1992 by ASME
Mutational Analysis of Stem-Loops in the RNA Packaging Signal of the Moloney Murine Leukemia Virus

Abstract The retroviral RNA genome is targeted for incorporation into the nascent virion particle by the ψ region, a specific block of RNA sequences near the 5′ end. A number of deletions and linker insertion mutations were introduced into the ψ region of cloned DNA of the Moloney murine leukemia virus, and the mutants were introduced into cells in culture and tested for their ability to direct the assembly of virions and the packaging of viral RNA. Only a small portion of the ψ region was important for packaging, containing the so-called stem-loops C and D. Additional mutants were used to demonstrate that the base pairing of stem D, and the sequence of loop D, were essential for normal packaging of the RNA. Two mutants with alterations near the 5′ splice donor were also replication-defective, probably due to effects on gene expression. The results allow a high-resolution definition of the RNA structures required during virus replication in culture.
Differential elution of histones from gel-trapped nuclei.

A method has been developed for characterizing at, submicrogram levels the heterogeneity of histones from purified nuclei. The histones are eluted with a smooth concentration gradient from nuclei trapped in polyacrylamide–gel threads and are collected in a micro fraction collector suitable for volumes in the 10–100 μl range. The gradient and fraction collection systems are governed by cam driven syringes. Samples obtained are subjected to electrophoresis in a starch-gel system and the gels are stained with a highly sensitive stain specific for guanidinium groups. Seven major and a similar number of minor components are demonstrated in the histones. The method of differential elution of trapped macromolecules is suitable for use with systems other than nuclei and histones.
Stable economic depreciation

This paper presents an equipment replacement model for a profit maximizing firm facing a downward sloping demand curve and establishes two main results. First, decisions on production levels and equipment replacement are independent. Second, there exists a depreciation schedule that is stable in the sense that neither firm nor government can argue for changes on purely economic grounds.
Aneuploidy in the miscarriages of infertile women and the potential benefit of preimplanation genetic diagnosis

Objective To evaluate the frequency of specific aneuploidies in miscarriages in an infertility practice and calculate the potential sensitivities of the different aneuploidy screening options for preimplantation genetic diagnosis (PGD) in this setting. Design Retrospective analysis. Setting Academic reproductive endocrinology and infertility practice. Patient(s) Women with miscarriages that had karyotype analysis on products of conception. Intervention(s) None. Main Outcome Measure(s) Karyotype of spontaneous abortions compared with commercially available PGD options. Result(s) Of the 273 karyotypes analyzed, 177 (64.8%) were abnormal. The average age of the patients was 37 ± 4.5 years. Using a limited five-probe panel, 54 of the 177 (31%) abnormal karyotypes would have been detected. In contrast, an extended PGD panel (using 9, 10, or 12 chromosome probes) would have detected 127, 131, and 140 of 177 abnormalities, 72%, 74%, and 79% respectively. The difference between the limited (5-probe) and extended (9-, 10-, and 12-probe) panels was statistically significant. There was not a statistically significant difference among the extended panels. Conclusion(s) Most of the abnormalities seen in miscarriages are detectable by PGD with extended panels. A significantly higher percentage of these abnormalities could be detected by screening for 9, 10, or 12 chromosomes compared with only 5.
Using qualia and novel representations in malware detection

Detecting network intruders and malicious software is a significant problem for network administrators and security experts. New threats are emerging at an increasing rate, and current signature and statistics-based techniques are failing to keep pace. Intelligent systems that can adapt to new threats are needed to mitigate these new strains of malware as they are released. This research develops a system that uses contextual relationships and information across different layers of abstraction to detect malware based on its qualia, or essence. By looking for the underlying concepts that make a piece of software malicious, this system avoids the pitfalls of static solutions that focus on predefined signatures or anomaly thresholds. If successful, this type of qualia-based system would provide a framework for developing intelligent classification and decision-making systems for any number of application areas.
Effect of cold rolling on the tensile properties of (Al2O3)p/Al composites

Abstract Cold rolling of extruded 6061 Al alloy composite reinforced with 10% of Al2O3 particulates along the transverse direction results in more uniform distribution of the particulates. This rolling is associated with a considerable amount of damage to the particulates. Room temperature tensile tests carried out on the rolled composites showed, with increasing reduction in rolling, significant decrease in strength and insignificant change in fracture strain along the longitudinal (extruded) direction. However, the same properties increased with increasing reduction in rolling along the transverse (rolling) direction. Such behaviors of rolled composites are analyzed on the basis of redistribution of the particulate clusters, disappearance of the particulate free zones, particulate damage, and the contribution of the individual particulate to the strengthening with the achievement of uniform distribution.
Iron oxide waste form for stabilizing 99Tc

Crystals of goethite were synthesized with reduced technetium [{sup 99}Tc(IV)] incorporated within the solid lattice. The presence of {sup 99}Tc(IV) as a substituting cation in the matrix and 'armoring' by an additional layer of precipitated goethite isolated the reduced {sup 99}Tc(IV) from oxidizing agents. These products were used to make monolithic pellets to quantify an effective diffusion coefficient for {sup 99}Tc from goethite waste form contacted with a synthetic Hanford IDF (integrated disposal facility) pore water solution (pH = 7.2, I = 0.05 M) at room temperature for up to 120 days in static reactors. XANES analysis of the goethite solids recovered post-run demonstrated that the {sup 99}Tc in the goethite crystals remains in the reduced {sup 99}Tc(IV) state. The slow release of pertechnetate concentration with time in the static experiments with the monolith followed a square root of time dependence, consistent with diffusion control for {sup 99}Tc release. An apparent diffusion coefficient of 6.15 x 10{sup -11} cm{sup 2}/s was calculated for the {sup 99}Tc-goethite pellet sample and the corresponding leaching index (LI) was 10.2. The results of this study indicate that technetium can be immobilized in a stable, low-cost Fe oxide matrix that is easy to fabricate andmore » these findings can be useful in designing long-term solutions for nuclear waste disposal.« less
Abstract CN06-01: Induction of oral cavity cancer in rats by (S)-N'-nitrosonornicotine, a constituent of smokeless tobacco

Smokeless tobacco products such as moist oral snuff are being promoted by the tobacco industry with a half billion dollars per year in advertising. It is likely that the prevalence of smokeless tobacco use will continue to increase in the U.S. Smokeless tobacco products are widely used in other parts of the world and are considered by the International Agency for Research on Cancer as causes of cancer of the oral cavity, esophagus and pancreas in humans. However, no previous study has reported the presence of a strong oral cavity carcinogen in these products. N9- Nitrosonornicotine (NNN) occurs in significant amounts in smokeless tobacco products, generally being found at levels of 1 - 10 μg/g tobacco. Since NNN has a chiral center, it exists as ( S )- and ( R )- enantiomers. ( S )-NNN is the major enantiomer in smokeless tobacco products. While racemic NNN (a 50:50 mixture of ( S )- and ( R )-NNN) has been previously shown to cause esophageal tumors in rats, the carcinogenicity of the individual enantiomers has not been reported. Based on our published metabolism and DNA binding studies of ( S )-NNN, we hypothesized that it might be a more powerful carcinogen than ( R )-NNN and, furthermore, that it might cause oral cancer. Groups of 24 male F-344 rats were treated with either ( S )-NNN (15 ppm), ( R )-NNN (15 ppm), or racemic NNN (30 ppm) in the drinking water for 15-20 months. Necropsy of 20 rats treated with ( S )-NNN demonstrated a 100% incidence of oral cavity tumors. More than 60 oral cavity tumors were observed, including benign and malignant tumors of the buccal mucosa, soft and hard palate, tongue, and pharynx. All rats also had esophageal tumors. ( R )-NNN was significantly less carcinogenic than ( S )-NNN. Racemic NNN also induced a high incidence of oral cavity and esophageal tumors. The results of this study demonstrate for the first time the presence of a strong oral cavity carcinogen in smokeless tobacco. ( S )-NNN is a prime target for elimination from these products as a positive step toward cancer prevention. Citation Format: Stephen S. Hecht, Sandra James-Yi, Gerard O9Sullivan, Irina Stepanov, Mingyao Wang, Fekadu Kassie, Steven Carmella, Pramod Upadhyaya, Silvia Balbo. Induction of oral cavity cancer in rats by (S)-N9-nitrosonornicotine, a constituent of smokeless tobacco. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr CN06-01.
Endovascular Treatment of Massive and Submassive Pulmonary Embolism

Massive and submassive pulmonary embolism constitutes the high- and intermediate-risk categories of pulmonary embolism. Both are associated with higher rates of mortality and morbidity and may benefit from more aggressive management than from standard anticoagulation alone. Endovascular treatment is a promising treatment modality that may offer added benefit at low additional risk.
Evaluation of medical cosultations in a predoctoral dental clinic

Abstract Objectives A patiet's medical condition, can affect the delivery of dental care. Medical consultation is indicated for dental patients whose medical history is uncertain or when physical assessment may indicate an untreated medical problem. The aims of this study were to evaluate the use of medical consultation and determine how it affects dental treatment plans in a predoctoral dental clinic program. Study design Reviews of 147 medical consultation requests were performed Results The main reasons for medial consultations were cardiovascular assessment (51.5%) and diabetic status determination (12.6%). In the cardiovascular assessment category, hypertension (48.1%) and heart murmur (17.9%) were primary concerns. Main dental concerns were the need for preoperative antibiotic prophylaxis (33.3%) and the use of vasconstrictors (20.4%). Overall, 32.1% medical consultations resulted in a alteration in dental treatment plans. As a result of medical consultations, 8% commenced their medical management. Conclusion These results indicated that medical consultations could reduce the medical risk associated with dental procedures and unnecessary atibiotic prophylaxis. Therefore for many dental patients, good communication between dentists and physicians is essential for adequate care.
LXII. Note on the length of the break-spark in an inductive circuit

(1901). LXII. Note on the length of the break-spark in an inductive circuit. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science: Vol. 2, No. 12, pp. 653-658.
Preparticipation examination: Role of the Upper Extremity Specialist and Sports Medicine Team

Abstract Annually, millions of high school and junior high school age students participate in athletics. At some time these individuals are required to have a preparticipation examination. Guidelines and requirements concerning this examination vary from state to state. It is usually apparent that the design and implementation of the examination are the result of concerned physicians and health care professionals. The health care team approach is necessary to represent a complete sports medicine program. It is this author's opinion that the health care team would benefit from active participation of a hand therapist. The knowledge and expertise this specialty encompasses would greatly enhance the effectiveness of the sports medicine program. A sample upper extremity examination is presented to serve as a guideline for the clinician. This is not intended to be a substitute for any part of the existing preparticipation examinations but rather to serve as an effective adjunct in the prevention of injury to young athletes.
Northern hemisphere summer ozone variability observed by POAM II

Zonal asymmetry in ozone mixing ratio was observed by POAM II during the 1994–1996 summers between 55°N and 65°N and between 21 km and 28 km in altitude. The zonal variance can be described as persistent large-scale ozone patterns that move approximately with the zonal mean wind. The histories of air parcels observed by POAM are deduced from 20-day back trajectories using UKMO winds which have been corrected for stationary anomalies. The ozone mixing ratio is found to correlate with the average latitude of the back trajectory throughout the summer, indicating that the zonal variance is a result of meridional transport. The meridional transport appears to be caused by breaking of westward-propagating waves that are evanescent in the summer easterly flow.
Artificial grammar learning in pigeons.

In two experiments, we developed a new methodology for studying complex stimulus control by spatial sequences of letters generated by artificial grammars. An artificial grammar is a system of rules that defines which letter sequences or strings are “grammatical.” In Experiment 1, pigeons learned to respond differently to strings conforming to a grammar versus strings that were nongrammatical distortions. Several different criteria all suggested that performance was controlled both by some short chunks of strings shared between reinforced training strings and novel transfer strings and by more complex sequential regularities. In Experiment 2, pigeons quickly and accurately learned to respond differently to strings conforming to one or the other of two different artificial grammars. As in Experiment 1, performance was controlled both by some short chunks and by more complex sequential regularities. The results are interpreted in terms of family resemblance and pose new goals for theories of complex stimulus control.
Local and near surface structure from diffraction

This special topic of Materials Science and Engineering A highlights novel applications of X-ray and neutron diffraction for the analysis of a range of materials, including conventional and nanostructured materials, thin films, bio-inspired materials, and superalloys. The development of ultra-brilliant synchrotron X-ray sources and recent advances in neutron diffraction provide important new opportunities for the analysis of local and near surface material structures at multiple length scales.
Riesz basis property of root vectors of non-self-adjoint operators generated by aircraft wing model in subsonic airflow

This paper is the third in a series of several works devoted to the asymptotic and spectral analysis of a model of an aircraft wing in a subsonic air flow. This model has been developed in the Flight Systems Research Center of UCLA and is presented in the works by Balakrishnan. The model is governed by a system of two coupled integro-differential equations and a two-parameter family of boundary conditions modeling the action of the self-straining actuators. The differential parts of the above equations form a coupled linear hyperbolic system; the integral parts are of the convolution type. The system of equations of motion is equivalent to a single operator evolution-convolution equation in the energy space. The Laplace transform of the solution of this equation can be represented in terms of the so-called generalized resolvent operator, which is an operator-valued function of the spectral parameter. This generalized resolvent operator is a finite-meromorphic function on the complex plane having the branch cut along the negative real semi-axis. Its poles are precisely the aeroelastic modes and the residues at these poles are the projectors on the generalized eigenspaces. In the first two papers (see [33, 34]) and in the present one, our main object of interest is the dynamics generator of the differential parts of the system. This generator is a non-self-adjoint operator in the energy space with a purely discrete spectrum. In the first paper, we have shown that the spectrum consists of two branches, and have derived their precise spectral asymptotics with respect to the eigenvalue number. In the second paper, we have derived the asymptotical approximations for the mode shapes. Based on the asymptotical results of the first two papers, in the present paper, we (a) prove that the set of the generalized eigenvectors of the aforementioned differential operator is complete in the energy space; (b) construct the set of vectors which is biorthogonal to the set of the generalized eigenvectors in the case when theremight be not only eigenvectors but associate vectors as well; and (c) prove that the set of the generalized eigenvectors forms a Riesz basis in the energy space. To prove the main result of the paper, we made use of the Nagy-Foias functional model for non-self-adjoint operators. The results of all three papers will be important for the reconstruction of the solution of the original initial-boundary-value problem from its Laplace transform in the forthcoming papers.
Physics: Fundamental Feynman

An account of the physicist's work reminds Leonard Mlodinow of the gulf between theory and experiment.
Overgeneral Autobiographical Memory, Emotional Maltreatment, and Depressive Symptoms in Adolescence: Evidence of a Cognitive Vulnerability-Stress Interaction.

Overgeneral autobiographical memory (OGM) is associated with depression and may confer risk for the development of depressed mood, but few longitudinal studies have evaluated OGM as a predictor of depressive symptoms in early adolescence, particularly in the context of environmental stressors. We investigated whether OGM and emotional maltreatment would interact to predict prospective increases in depressive symptoms in early adolescents and whether these effects differed by race. Among 174 seventh-graders, OGM and familial emotional abuse interacted to predict depressive symptoms eight months later, controlling for initial depressive symptoms. Specifically, emotional abuse predicted increases in depressive symptoms among Caucasian adolescents with more OGM, but not among those with less OGM. This association was not significant for African American adolescents. These results provide support for a cognitive vulnerability-stress relationship between OGM and emotional abuse in early adolescence and suggest that these mechanisms of risk for depression may be specific to Caucasian adolescents.
When Efficiency Is Unbelievable: Normative Lessons from 30 Years of City–County Consolidations

We use a new model of city-county consolidation to analyze 12 local government consolidation attempts during the last three decades. Using a rigorously designed comparative case study, we identify the critical variables that explain why some consolidations succeed and others fail. Arguments for consolidation typically fail when they focus on the increased equity to be gained from the redistribution of revenues from the suburbs to central cities. Traditional arguments that are based on increased efficiency are also unsuccessful. Instead, the essential element of a successful consolidation is a group of civic elites who define the economic development vision for the community, determine that the existing political structure is incapable of supporting and implementing that vision, and convince the voters that city–county consolidation is the key to economic development that will benefit the whole community, not just the elites.
MicroCT evaluation of normal and osteoarthritic bone structure in human knee specimens

Although trabecular bone structure has been evaluated, variation with knee compartment and depth from joint surface is not completely understood. Cadaver knees were evaluated with microcomputed tomography analysis for these variations. Objective differences were compared between: medial vs. lateral compartments; femoral vs. tibial bone; and normal vs. arthritic knees. Depth dependent changes in the parameters were observed for the first 6 mm of the cores in normal knees: BV/TV, Tb.N and Conn.D gradually decrease, while Tb.Sp and SMI increase. In the first 6 mm of the normal tibia BV/TV, Tb.N, and Tb.Th are greater than in the femur on both the medial and lateral compartments while Tb.Sp, SMI, and Conn.D are lower. The medial compartment values for BV/TV, Tb.N, Tb.Th and Conn.D are generally greater than for the lateral in both the femur and tibia while Tb.Sp and SMI are lower. In comparison of normal vs. arthritic knees significant differences are observed in the first 6 mm of the medial tibia. With arthritis BV/TV and Tb.Th are lower, while SMI and Tb.Sp are higher. Tb.N and Conn.D show no statistically significant difference. The bone structure variations are, thus, most prominent in the first 6 mm of depth and medial compartment bone is generally more structurally sound than lateral. Severely arthritic bone changes are most prominent in the medial compartment of the tibia and bone structure is less sound in severe arthritis.
Caries potentiating effect of ethylene diamine tetraacetic acid in the rat.

SummaryThe addition of 0.5% EDTA to a cariogenic diet appeared to potentiate caries to a marked degree in the white rat. Concomitantly, the hematocrit value is significantly lowered, and almost complete inhibition of incisor pigmentation is found. These effects of EDTA do not seem to be associated with its ability to decalcify rat molar teeth in vivo. Citrate and calgon added to a cariogenic diet and present in the drinking fluid do not significantly increase the severity of caries.
Plains boomers and the creation of the Great American Desert myth

Abstract Although the myth of a Great American Desert occupying a major portion of the Great Plains was accepted by only a small majority of the American population and for only a short period of time in the mid-nineteenth century, settlers and promoters or “boomers” of the Great Plains perpetuated the desert myth from mid-century onward. The tradition of the desert of the Plains was invented, nurtured, and promoted by both Plains settlers and boomers in an attempt at self-justification and self-promotion. From the perspective of settlers, viewing the Plains as desert lent an aura of heroism to their settlement efforts. From the perspective of promoters, perpetuating the image of the Great American Desert and contrasting it with the actuality of successful agricultural occupation of the Plains allowed promotional literature to make claims about the ability of human action to alter the natural environment. The promotion of the desert myth was so effective that, even today, Plains residents embrace the desert tradition. Such an action affirms for them their wisdom and their ability to see the rich productive land which early explorers were unable to comprehend. The persistence of the desert tradition also glorifies the hardiness of Plains dwellers, both past and present, in coping with a harsh landscape.
InAs/GaSb strained layer superlattice detectors with nBn design

Abstract We have investigated the electrical and optical properties of an nBn based Type-II InAs/GaSb strained layer superlattice detector as a function of absorber region background carrier concentration. Temperature-dependent dark current, responsivity and detectivity were measured. At T = 77 K and Vb = 0.1 V, with two orders of magnitude change in doping concentration, the dark current density increased from ∼0.3 mA/cm2 to ∼0.3 A/cm2. We attribute this to a depletion region that exists at the AlGaSb barrier and the SLS absorber interface. The device with non-intentionally doped absorption region demonstrated the lowest dark current density (0.3 mA/cm2 at 0.1 V) with a specific detectivity D∗ at zero bias equal to 1.2 × 1011 Jones at 77 K. The D∗ value decreased to 6 × 1010 cm Hz1/2/W at 150 K. This temperature dependence is significantly different from conventional PIN diodes, in which the D∗ decreases by over two orders of magnitude from 77 K to 150 K, making nBn devices a promising alternative for higher operating temperatures.
Developing a linear algorithm for cubing a cyclic permutation

A linear algorithm is developed for cubing a cyclic permutation stored as a function in an array. This continues work discussed in [0] and [1] on searching for disciplined methods for developing and describing algorithms that deal with complicated data structures such as linked lists. Here, a different representation of a cyclic permutation reveals a simple algorithm; then, an equally simple coordinate transformation is used to yield the final algorithm.
Biological studies of Liriomyza huidobrensis (Diptera: Agromyzidae) on chrysanthemum, aster, and pea.

Selected biological characteristics of Liriomyza huidobrensis (Blanchard) were determined under constant laboratory conditions, using chrysanthemum, aster, and pea as host plants. Larval development time was shorter on peas than on chrysanthemum or aster; no differences were found when durations of the egg or pupal stages or adult longevity were compared among the three hosts. The pattern of feeding and oviposition throughout the female life span was similar on all hosts. More feeding usually occurred on chrysanthemum; however, the largest number of pupae per female and the greatest pupal viability (73%) was obtained from insects reared on peas, suggesting that they are the optimal host for L. huidobrensis .
Aggressive Crime, Alcohol and Drug Use, and Concentrated Poverty in 24 U.S. Urban Areas

The nexus between substance use and aggressive crime involves a complex interrelationship among mediating individual and community-level variables. Using multilevel logistic regression models, we investigate how community-level concentration of poverty variables mediate the predictive relationships among individual level social attachment variables and substance use on aggressive crime in a large national sample of male arrestees (N = 20,602) drawn from 24 U.S. urban areas. The findings support our hypothesis that individual social attachments to marriage and the labor force (education and employment) are the principal individual-level pathway mediating the substance abuse/aggression nexus. In the random intercept model, 3.17% of the variation not explained by the individual-level predictor variables is attributable to community-level variation in urban area female-headed households and households receiving welfare. This confirms our hypothesis that social structural conditions of an urban environment differentially expose persons to conditions that predict being arrested for an aggressive crime. Our findings tend to counter the cultural theorists who argue for an indigenous culture of violence in inner-city ghettos and barrios.
Youth purpose and the perception of social supports among African-American girls

Purpose in adolescence is linked to positive developmental outcomes, and yet little is known about how youth purpose is supported by people and institutions that occupy the ecologies in which young people are embedded. Little is known too about how African-American youths envision themselves in the future, and understanding the nature of their purposes may uncover critical information about these adolescents’ aspirations. Associations between purpose and social supports were examined in a sample of 46 adolescent girls in the southeastern United States (Mean age = 12.83 years; SD = 1.14 years) (African-American/Black = 78.3%; Multiracial = 15.2%; White/Caucasian = 6.5%). Qualitative content analysis of interviews identified five forms of purpose experienced by these young people. Surveys measured perceived presence and importance of social supports of parents, teachers, close friends, classmates, and school environment, as well as emotional, informational, appraisal, and instrumental support across these s...
Recent progress in short-distance optical interconnects

Short distance optical interconnects are under development for a range of applications including local area networks, optical backplanes, and optoelectronic accelerators or signal processors. In some applications, the aggregate bandwidth required cannot be provided with electrical interconnects, offering an obvious advantage for optics, while in others it is the density of available interconnects which motivates the use of optics. In most commercial applications, it is the cost of the interconnect solution which will affect its acceptance by system integrator. For optics to be applied in a broad range of applications, greater transparency must be provided to the system integrator. We describe both intercabinet and intracabinet interconnects in which the addition of optical interconnects has been designed to perturb the overall system as little as possible and yet still take advantage of optics.
Thermohaline convection at density ratios below one: A new regime for salt fingers

Author Posting. © Sears Foundation for Marine Research, 2011. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 69 (2011): 779-795, doi:10.1357/002224011799849471.
The economics of tiered pricing and cost functions: Are equity, cost recovery, and economic efficiency compatible goals?

Abstract The paper develops a framework to analyze equity and economic efficiency of increasing block rates (IBR) for regulated products such as electricity or water. The model assumes that consumers are heterogeneous in their demand characteristics. Conditions are identified under which economic efficiency and cost recovery can be achieved in a manner that also reduces inequality, which is measured through changes in the Gini coefficient of net income. The use of IBR pricing is found to have a limited capacity to address equity issues while maintaining a balanced budget, as the balanced budget limits the size of the tier. Economic efficiency constraints combined with the balanced budget limit the subsidy. The capacity of IBR pricing to modify equity outcomes increases if supply costs are diverse. Under IBR, a supplier with significant variability in its marginal costs has a greater ability to improve equity while still remaining revenue neutral and maintaining economic efficiency. Under marginal cost pricing, the Gini coefficient is primarily affected by parameters of the demand function but, with IBR, both demand and supply parameters impact this measure. The results are illustrated with a numerical analysis of household water consumption from four utilities in the western United States.
Batch adsorption for pore diffusion with film resistance and an irreversible isotherm

Equations are developed for finite-batch, irreversible adsorption where both pore diffusion and film resistance are significant. Quasi-steady state behavior is assumed and comparisons are made for sheets, cylinders, and spheres. The equations for the three shapes are generalized to a single form. For equal volumes of adsorbent, when the external film controls, spheres attain equilibrium more quickly than cylinders, and cylinders more quickly than sheets. When internal diffusion controls and the ratio of the final to the initial solution concentration is high, this ordering of equilibrium times is preserved; however, if the ratio is very low, the ordering is reversed. On a mis au point des equations relativement a une adsorption discontinue, finie et irreversible, dans laquelle la diffusion interstitielle et la resistance du film jouent un role important. On suppose que le comportement est celui d'un regime quasiment stable et l'on fait des comparaisons en employant des feuilles, des cylindres et des spheres. On generalise en une seule forme les equations relatives aux trois formes indiquees. Dans le cas volumes egaux de l'absorbant, les spheres atteignent un equilibre plus rapidement que les cylindres et ces derniers plus rapidement que les feuilles, lorsque le film externe domine. Lorsque la diffusion interne domine et que le rapport entre la concentration finale et la concentration initiale est considerable, l'ordre des temps d'equilibre demeure le měme qu'indique, mais, si ledit rapport est tres faible, l'ordre en question est inverse.
Evolving applications in the use of bone-anchored hearing aids.

The bone-anchored hearing aid (BAHA) is an effective means of intervention, its use being well documented in persons with chronic conductive pathology and congenital aural anomalies. This article d...
Cell-free translation of purified avian sarcoma virus src mRNA.

Abstract Avian sarcoma virus 21 S RNA, purified by hybridization from virus-infected cells, was translated in a cell-free system. The major product of translation was a protein of 60,000 daltons. This protein was the same as authentic pp60 src , the product of the ASV src gene, when compared by electrophoretic mobility in polyacrylamide gels, immunological reactivity and partial protease digestion. These findings confirm that the 21 S ASV RNA serves as mRNA for pp60 src . Furthermore, pp60 src is the only major product of translation of the src gene and is apparently synthesized without a cleavable signal sequence.
Carotenoid-chlorophyll complexes: Ready-to-harvest

The fundamental interactions between naturally occurring pigments in light-har- vesting systems are responsible for the high efficiency of the photosynthetic apparatus. We describe the role of carotenoids (Cars) in light-harvesting systems, including our work eluci- dating the mechanism of energy transfer from the optically dark Car singlet excited state (S 1 ) to chlorophyll (Chl) and calculations on the electronic structure of Cars by means of time- dependent density functional theory (TDDFT). We highlight new studies on the charge-trans- fer state of the Car, peridinin (Per), which enhances the light-harvesting efficiency of the Car by increasing the electronic coupling to Chl. The role of another Car, zeaxanthin (Zea), is dis- cussed with respect to its role in the mechanism of the feedback deexcitation quenching in green plants, a vital regulation process under light conditions which exceed photosynthetic capacity. Lastly, we provide insight on how the 96 Chls in Photosystem I are optimized to generate a pigment-protein complex which utilizes solar energy with near unit efficiency.
The Method of Reflection for Solving the Time-Optimal Hamilton-Jacobi-Bellman Equation on the Interval Using Wavelets

In this paper we use the antiderivatives of wavelets to efficiently represent functions which are defined over a bounded interval and which satisfy a boundary condition in the interior of this interval. The functions we want to approximate are typically nonsmooth at the origin. Such functions appear as solutions to Hamilton-Jacobi-Bellman (HJB) equations for time-optimal control problems. We first give the degree of approximation of the antiderivatives and then propose a wavelet reflection algorithm (WRA) to solve numerically the time-optimal HJB equation on the interval. Several numerical examples demonstrate the advantages of the technique developed in this paper over polynomial expansions
Comparative analysis of complete genomes reveals gene loss, acquisition and acceleration of evolutionary rates in Metazoa, suggests a prevalence of evolution via gene acquisition and indicates that the evolutionary rates in animals tend to be conserved

In this study we systematically examined the differences between the proteomes of Metazoa and other eukaryotes. Metazoans (Homo sapiens, Ceanorhabditis elegans and Drosophila melanogaster) were compared with a plant (Arabidopsis thaliana), fungi (Saccharomyces cerevisiae and Schizosaccaromyces pombe) and Encephalitozoan cuniculi. We identified 159 gene families that were probably lost in the Metazoan branch and 1263 orthologous families that were specific to Metazoa and were likely to have originated in their last common ancestor (LCA). We analyzed the evolutionary rates of pan-eukaryotic protein families and identified those with higher rates in animals. The acceleration was shown to occur in: (i) the LCA of Metazoa or (ii) independently in the Metazoan phyla. A high proportion of the accelerated Metazoan protein families was found to participate in translation and ribosome biogenesis, particularly mitochondrial. By functional analysis we show that no metabolic pathway in animals evolved faster than in other organisms. We conclude that evolution in the LCA of Metazoa was extensive and proceeded largely by gene duplication and/or invention rather than by modification of extant proteins. Finally, we show that the rate of evolution of a gene family in animals has a clear, but not absolute, tendency to be conserved.
Learn++.MT: A new approach to incremental learning

An ensemble of classifiers based algorithm, Learn++, was recently introduced that is capable of incrementally learning new information from datasets that consecutively become available, even if the new data introduce additional classes that were not formerly seen. The algorithm does not require access to previously used datasets, yet it is capable of largely retaining the previously acquired knowledge. However, Learn++ suffers from the inherent ”out-voting” problem when asked to learn new classes, which causes it to generate an unnecessarily large number of classifiers. This paper proposes a modified version of this algorithm, called Learn++.MT that not only reduces the number of classifiers generated, but also provides performance improvements. The out-voting problem, the new algorithm and its promising results on two benchmark datasets as well as on one real world application are presented.
Military Social Work: A Multi-Country Comparison

Social work has a long tradition of service to the military in many countries. How it has developed in each country is unique to the historical development of the military and the country's social work educational infrastructure. This article describes the growing interest in international social work, what military social work practice is and how it has evolved in several countries; outlines a new model for cross-national comparison of military social work evolution; and highlights current trends and future directions for international military social work.
Activity of Proteus mirabilis FliL Is Viscosity Dependent and Requires Extragenic DNA

ABSTRACT Proteus mirabilis is a urinary tract pathogen and well known for its ability to move over agar surfaces by flagellum-dependent swarming motility. When P. mirabilis encounters a highly viscous environment, e.g., an agar surface, it differentiates from short rods with few flagella to elongated, highly flagellated cells that lack septa and contain multiple nucleoids. The bacteria detect a surface by monitoring the rotation of their flagellar motors. This process involves an enigmatic flagellar protein called FliL, the first gene in an operon ( fliLMNOPQR ) that encodes proteins of the flagellar rotor switch complex and flagellar export apparatus. We used a fliL knockout mutant to gain further insight into the function of FliL. Loss of FliL results in cells that cannot swarm (Swr − ) but do swim (Swm + ) and produces cells that look like wild-type swarmer cells, termed “pseudoswarmer cells,” that are elongated, contain multiple nucleoids, and lack septa. Unlike swarmer cells, pseudoswarmer cells are not hyperflagellated due to reduced expression of flaA (the gene encoding flagellin), despite an increased transcription of both flhD and fliA , two positive regulators of flagellar gene expression. We found that defects in fliL prevent viscosity-dependent sensing of a surface and viscosity-dependent induction of flaA transcription. Studies with fliL cells unexpectedly revealed that the fliL promoter, fliL coding region, and a portion of fliM DNA are needed to complement the Swr − phenotype. The data support a dual role for FliL as a critical link in sensing a surface and in the maintenance of flagellar rod integrity.