cssi/SciSciGPT-SciSciNet huggingface dataset:
Nonlinear control of a membrane mirror strip actuated axially and in bending

The sliding mode technique is used to control the deformation of a membrane mirror strip augmented with two macrofiber composite bimorphs located near the ends of the strip. The first bimorph is actuated in bending and the second is actuated axially. The structure is modeled as an Euler-Bernoulli beam under tensile load and the macrofiber composite patches are modeled as monolithic piezoceramic wafers. To cast the system into a finite-dimensional state-space form, the finite element method is used, and the model presented accounts for the dynamics of the augmented bimorphs. The membrane strip is placed under uniform tension. Because one of the bimorphs acts axially, the resulting tension in the membrane strip is discontinuous at the location of this bimorph and, consequently, the obtained model is nonlinear. First, we validate the model experimentally by considering the system in its quasi-linear state, then we consider the control problem. We formulate the regulation problem by using the sliding mode technique. Additionally, to allow coupling this system with an adaptive optics scheme, the shape-control problem is considered as well. The control law uses both actuators: the bending and axial bimorphs. However, a system singularity dictates using a switching command to avoid this singularity. Various examples are presented for the regulation and shape-control problems. The simulation results demonstrate the efficacy of the proposed control law.
Multi-sensor activation for temporally correlated event monitoring with renewable energy sources

Future sensor networks would comprise sensing devices with energy-harvesting capabilities from renewable energy sources, such as solar power. This paper focuses on design of efficient algorithms for multi-sensor activation to optimise overall event detection probability in presence of uncertainties in event and recharge processes. We formulate the dynamic multi-sensor activation question in a stochastic optimisation framework, and show that a time-invariant threshold policy, which maintains an appropriately chosen number of sensors active at all times, is optimal in absence of temporal correlations. Moreover, the same energy-balancing time-invariant threshold policy approaches optimality in presence of temporal correlations as well, albeit under certain limiting assumptions. We also analyse the class of correlation-dependent threshold policies and derive the range for energy-balancing thresholds. Through simulations, we compare the proposed time-invariant policy with energy-balancing correlation-dependent policies, and observe that although the latter may perform better, the performance difference is rather small in the cases studied.
Erratum to: An inversion effect modified by expertise in capuchin monkeys

J. J. Pokorny (&) C. E. Webb F. B. M. de Waal Department of Psychology, Living Links, Yerkes National Primate Research Center, Emory University, 954 Gatewood Road, Atlanta, GA 30329, USA e-mail: jpokorn@emory.edu Fig. 2 a Example of an upright trial for capuchin face stimuli. The odd individual, and correct response, is the top right position. b Example of an inverted trial for capuchin face stimuli. The odd individual is depicted in the bottom left position
Genetic risk factors for infection in patients with early rheumatoid arthritis.

We analyzed clinical and genetic factors contributing to infections in 457 subjects with early rheumatoid arthritis (RA) enrolled in a prospective, 1-year clinical trial of methotrexate and the TNF inhibitor etanercept. Subjects were genotyped for the following single nucleotide polymorphisms (SNPs): (TNF −308, −238, and +488); lymphotoxin-α (LTA) (LTA +249, +365, and +720); and Fc gamma receptors FCGR2A 131 H/R; FCGR3A 176 F/V; and FCGR3B NA 1/2 and genotypes were correlated with infections. At least one URI was noted in 52% of subjects (99/191) with the NA2/NA2 genotype of the neutrophil-specific FCGR3B gene, compared to 42% (77/181) of those with the NA1/NA2 genotype and 39% (23/59) of those with the NA1/NA1 genotype (P=0.038). Urinary tract infection (UTI) was associated with the TNF −238 A (odds ratio(OR) 2.56, 95% confidence interval (CI) 1.05–6.25) and LTA +365 C (OR 1.73, 95% CI 1.07–2.79) alleles, and marginally with the FCGR3A F allele (OR 1.72, 95% CI 0.99–3.00). There was a striking linear correlation between UTI and the number of risk alleles defined by these three SNPs (P<0.001), suggesting an additive effect on susceptibility. These findings have important implications for the role of genetics in susceptibility to bacterial and viral infections.
Lactate production during maximal and submaximal exercise in patients with chronic heart failure.

In patients with chronic heart failure whose cardiac output response to exercise is impaired, determination of anaerobic threshold may provide a useful and objective approach to grade the severity of heart failure. In such patients performing upright treadmill exercise to exhaustion, this study examined the reproducibility of the response of cardiac output and mixed venous lactate concentration when the exercise test was repeated the same or next day, the nature of this response after rest and exercise cardiac output levels were augmented by the cardiotonic agent amrinone and the response of lactate during symptom-limited submaximal exercise performed at either aerobic or anaerobic levels of work for each patient. Findings were: 1) the response of cardiac output and mixed venous lactate was reproducible (p
Tau Filament Length Distribution Reflects End-To-End Annealing

Tau is a microtubule associated protein that normally functions as a monomer in league with the microtubule cytoskeleton. However, in Alzheimer's disease (AD), tau aggregates to form filamentous inclusions in cell bodies (neurofibrillary tangles, NFT) and cell processes (dystrophic neurites and neuropil threads). The appearance of tau-bearing lesions correlates with neurodegeneration and cognitive decline, consistent with a connection between tau aggregation and disease progression. Indeed, in biological models, tau aggregates are toxic, with potency inversely proportional to aggregate size. However, the relationship between these species and the aggregation pathway is unknown.Here we investigate the aggregation mechanism of tau protein in vitro in an effort to identify interactions that manifest size dependence. The fits of a mathematical model describing simple nucleation-elongation polymerization to aggregation time-series, consistently overestimated filament growth rate while underestimating filament length distribution, indicating the presence of a secondary process in the pathway. On the basis of filament mixing and shearing experiments, we identified end-to-end annealing as a novel secondary interaction of nascent tau filaments. With the addition of an end-to-end annealing term to the mathematical model in equilibrium with filament fragmentation, we found improved fits for both time series and filament length distributions. In addition to quantifying the intrinsic rate constants for annealing and fragmentation, the model provided evidence for their dependence on filament length. The results indicate that filament ends are active, and that their propensity to engage in homotypic interactions is length dependent. We propose that heterotypic interactions at filament ends are candidate mediators of toxicity in biological models.
Comparison of state-of-the-art transmission constrained unit commitment formulations

The paper reviews and compares several mixed-integer linear programming formulations of the transmission constrained unit commitment problem. It analyzes these formulations and provides extensions that properly address all the generator initial conditions. Computing times to solve the unit commitment problem using these different formulations are analyzed and compared. Tests were performed using a version of the IEEE RTS-96 system that has been updated to include generator types that better reflect contemporary generation mixes. Detailed data on all the power system parameters are provided, including initial generator conditions.
An Algorithm for Computing the Number of Distinct Spectral Vectors in Thematic Mapper Data

A computationally efficient method was developed to compute the number of distinct spectral vectors and their frequency of occurrence in Landsat-4 Thematic Mapper (TM) data. The algorithm first partitions the image into spectrally disjoint subsets and then computes the frequency distribution of distinct spectral vectors within each subset from a multidimensional histogram. The overall frequency distribution is tabulated by accumulating the results from each subset. The number of distinct spectral vectors could be used as a measure of potential storage compaction of alternate data representations for data compression, or as a measure of information content in the comparison of spectral band combinations and/or spatial resolutions for an image. Results from processing three 512 X 512 pixel Landsat-4 TM images and one Landsat-4 Multispectral Scanner (MSS) image are presented as examples. An algorithm for computing the frequency distribution of distinct spectral vectors in MSS data is given in the Appendix.
Fiber-optic atmospheric turbulence sensor.

A novel dual-air-gap fiber-optic Mach–Zehnder interferometer is proposed for the direct measurement of the atmospheric optical turbulence structure constant Cn2. The shot-noise-limited minimum detectable structure constant is estimated to be 4.5 × 10−20 m−2/3, which is more than 2 orders of magnitude below a typical value of 10−17 m−2/3 for weak turbulence. This sensor is suitable for the measurement of atmospheric turbulence over land and ocean surfaces.
Classical ballet: the full-contact sport.

Stretanski MF: Classical ballet: The full-contact sport. Am J Phys Med Rehabil 2002;81:392–393.
Nutrition and fetal brain maturation. II. Impact of maternal starvation on changing levels of acetylcholinesterase and enolase in vitro.

The impact of maternal starvation during Days 17–20 of gestation was examined in 20-day fetal rat brain tissue cultured for 6 days in MEM and 10% adult rat serum. Acetylcholinesterase (AChE) activities were consistently greater in fetal brain cell cultures from starved mothers. When fetal tissues from starved mothers were continuously exposed to 72-h fasted serum, AChE activities increased from 1.03±0.14 to 1.59±0.21 μmol/h/mg protein (P<0.001). In fetal tissues from fed mothers, lower AChE activities were increased from 0.78±0.09 to 1.04±0.07 μmol/h/mg protein (P<0.05) when 72-h fasted serum was used to replace the fed serum during incubation. When fetal brain cell cultures from fed mothers were exposed for 6 days to graded concentrations of fed serum (2.5–15%), the activities of AChE fell reciprocally from 1.34±0.10 to 0.82±0.12 μmol/h/mg protein (P<0.05). The levels of AChE activity in tissues exposed to fasted serum were consistently greater, but fell similarly from 1.62±0.10 to 0.97±14 μmol/h/mg protein (P<0.01), when serum concentrations were increased from 2.5 to 15%. AChE activities were 30% higher in tissues incubated with cycloheximide 10−3 M (P<0.02). Unlike AChE, fetal brain enolase activities were unaffected by maternal starvation. In fetal brain cell cultures from fed mothers, enolase fell from 1.85±0.10 to 1.37±0.12 μmol/min/mg protein following exposure to fasted instead of fed serum (P<0.02). In fetal cultures from starved mothers, enolase activities were depressed similarly from 1.76±0.08 to 1.41±0.09 μmol/min/mg protein when fasted replaced fed serum (P<0.02). Thus, the fetal brain cell cultures appear to maintain enzymatic realignments imposed by maternal starvation for at least 6 days. In addition, serum from fasted animals has significant growth inhibiting properties manifested by heightened activities of AChE and lower activities of enolase.
A Theoretical and Empirical Argument for Centralized Regional Sewer Planning

Abstract It has long been taken as an article of faith that there are public benefits to centralized sewer service districts operating on a regional scale. Yet this belief, in our opinion, has never been adequately tested. We use capitalization theory to formulate such a test. Planners argue that regional sewer planning done on behalf of and implemented by a regional sewer agency may offer benefits in the form of scale economies, a high level of comprehensive and coordinated infrastructure and land use planning among jurisdictions within the region, and processing efficiencies. These benefits should result in development savings that are capitalized in a competitive land market. In this paper, we apply a model of our theory to a case stud?. Our results suggest that centralized regional sewer planning does offer land development savings that are capitalized into land values. We offer several implications that this paper has for regional planning.
Electromagnetic basis of drill-rod telemetry

Some calculated results are presented for the signal that can be propagated to the surface from a toroidal coil source near the bottom of a drill rod. Optimum frequencies are predicted to occur in the range 10?100 Hz for depths of the order of several kilometres.
Actuator gain distributions to analytically meet specified performance capabilities in serial robot manipulators

A serial robotic manipulator arm is a complex electromechanical system whose performance is characterized by its actuators. The actuator itself is a complex nonlinear system whose performance can be characterized by the speed and torque capabilities of its motor, and its accuracy depends on the resolution of the encoder as well as its ability to resist deformations under load. The mechanical gain associated with the transmission is critical to the overall performance of the actuator since it amplifies the motor torque, thus improving the force capability of the manipulator housing it, reduces the motor speed to a suitable output speed operating range, and amplifies the stiffness improving the precision under load of the overall system. In this work, a basic analytic process that can be used to manage the actuator gain parameter to obtain an improved arm design based on a set of desired/required performance specifications will be laid out. Key to this analytic process is the mapping of the actuator parameters (speed, torque, stiffness, and encoder resolution) to their effective values at the system output via the mechanical gains of the actuators as well as the effective mechanical gains of the manipulator. This forward mapping of the actuator parameters allows the designer to determine how each of the parameters influences the functional capacity of the serial manipulator arm. The actuator gains are then distributed along the effective length of the manipulator to determine their effects on the performance capabilities of the system. The analytic formulation is also demonstrated to be effective in addressing the issue of configuration management of serial robotic manipulators where the goal is to assemble a system that meets some required performance specifications. To this end, two examples demonstrating a solution of the configuration management problem are presented. The analytic process developed based on the mapping of the mechanical parameters of the actuator to their effective values at the system output is shown to dramatically reduce the effort in the initial phases of the design process, meaning that the number of design iterations can be dramatically reduced.
Imaging aberrations from null correctors

To test an aspheric surface, usually a null lens is designed to create an aspheric wavefront that matches the surface. The null lens also relays the image of the surface under test to the interferometer. The effect of image distortion from the null lens is well known, and is accommodated by remapping the data. Imaging aberrations created by the null lens also affect the measurement by smoothing out wavefront errors which correspond to ripples in the surface. This leads to data that does not faithfully represent the surface. We characterize this smoothing using a measurement transfer function, which is analogous to the modulation transfer function used to quantify the performance of imaging systems. In this paper we present a technique and tools for predicting the transfer function for a null test.
Ligand dissociation from mono-substituted derivatives of hexacarbonylchromium (Cr(CO)5L, L P(C6H5)3, P(C4H9)3, P(OCH3)3, P(OC6H5)3, and As(C6H5)3)

Abstract The rates of dissociation of the unique ligand from Cr(CO)5L have been determined from L  P(C6H5)3, P(OC6H5)3, P(OCH3)3, and As(C6H5)3 by reaction with CO. The reactions were investigated from 80140°C and activation parameters were determined. The rate data were fully consistent with rate-determining dissociation of the ligand L. The order of ligand lability is As(C6H5)3 > P(C6H5)3 > P(OC6H5)3 > P(OCH3)3. For L  P(C4H9)3 an equilibrium was observed and the equilibrium constant evaluated at 140 and 170°C. The equilibrium greatly favors Cr(CO)5P(C4H9)3 as the product. These studies allow the ligand binding to be compared quantitatively for these complexes. An activation of the CrP bond by room light has been noted.
Beyond the college walls.

The author outlines historical and current reasons that the National Institutes of Health (NIH) and academic medicine are inherently political and are now facing expanding political exposure. She emphasizes especially the power of modern discoveries in biology; this power stems from the many practical benefits that these discoveries can bring and their economic implications, and the growing public awareness of these benefits and implications. She then discusses the political realities of the biomedical enterprise, illustrating them by describing the nature of issues surrounding (1) the NIH budget and (2) technology transfer. Discussion of the latter topic includes a detailed description of controversies about patents (which revolve around the issue of who owns and controls the distribution and use of scientific information) and several important policy issues that are raised by these controversies (e.g., should there be uniform international policies regarding intellectual property rights associated with discoveries of novel biologically expressed genes of uncertain in-vivo function, and if so, how is that achieved?). The author concludes by stating that these examples of the politics of knowledge and of the NIH are among many vital biomedical issues of American life (which she lists) that require the academic medicine community to look beyond its own walls and participate in the complex world of politics and public policy.
A Proposed Mechanism for Silica Supported Chromium HDPE Catalyst Activation

Abstract The decomposition of Cr 3 (C 2 H 3 O 2 ) 7 (OH) 2 /SiO 2 in oxidizing, inert, and reducing environments was studied using isothermal kinetics, temperature-programmed reaction (TPRxn), and variable-temperature diffuse-reflectance infrared spectroscopy (VT-DRIFTS). Based upon these results a mechanism is proposed for the activation of silica-supported basic chromium acetate. The decompositions in N 2 and CO/N 2 mixtures appear very similar. The activation energies are within experimental error, and both exhibit second-order rate dependencies with respect to the surface acetate species. TPRxn results show that the Cr compound influences support dehydroxylation, but VT-DRIFT spectra show no evidence of Cr bonding to the SiO 2 surface. When CO is present, silica dehydroxylation appears to proceed via a water–gas shift type of reaction producing CO 2 and H 2 rather than H 2 O. In oxygen, Cr compound decomposition occurs at temperatures 90°C lower than in inert or reducing environments. The reaction orders are 1/2 for oxygen and 1 for the surface acetate species. The activation energy is comparable to that calculated for the other two media. VT-DRIFT spectra show that oxygen induces a greater degree of hydroxyl removal and formation of Cr–O/Cr=O bonds concurrent with and subsequent to recorded decomposition temperatures. In this way they support TPR findings and suggest Si–O–Cr bond formation. It appears that the rate-limiting step in the activation mechanism is removal of the acetate methyl group. In oxygen this involves dissociative activation of oxygen on the Cr center and subsequent combustion. In the other environments migration is necessary to allow hydrogen transfer between two acetate groups to form methane and leave behind a hydrocarbon fragment. This explains the different temperatures of decomposition in the various media and the second-order rate dependence upon acetate in N 2 and CO/N 2 . The lack of apparent Cr–SiO 2 bond formation in nonoxidizing environments allows surface migration of Cr compounds which makes this mechanism feasible.
Expanding networks of RNA virus evolution

In a recent BMC Evolutionary Biology article, Huiquan Liu and colleagues report two new genomes of double-stranded RNA (dsRNA) viruses from fungi and use these as a springboard to perform an extensive phylogenomic analysis of dsRNA viruses. The results support the old scenario of polyphyletic origin of dsRNA viruses from different groups of positive-strand RNA viruses and additionally reveal extensive horizontal gene transfer between diverse viruses consistent with the network-like rather than tree-like mode of viral evolution. Together with the unexpected discoveries of the first putative archaeal RNA virus and a RNA-DNA virus hybrid, this work shows that RNA viral genomics has major surprises to deliver.
A New Approach to Pseudoaneurysm of the Ascending Aorta

Abstract A pseudoaneurysm of the ascending aorta was repaired successfully with Fogarty balloon occlusion and bypass employing cardiotomy suckers. This previously unreported application of a basic vascular technique can simplify management in selected patients.
A laboratory exercise using a physical model for demonstrating countercurrent heat exchange

A physical model was used in a laboratory exercise to teach students about countercurrent exchange mechanisms. Countercurrent exchange is the transport of heat or chemicals between fluids moving in opposite directions separated by a permeable barrier (such as blood within adjacent blood vessels flowing in opposite directions). Greater exchange of heat or chemicals between the fluids occurs when the flows are in opposite directions (countercurrent) than in the same direction (concurrent). When a vessel loops back on itself, countercurrent exchange can occur between the two arms of the loop, minimizing loss or uptake at the bend of the loop. Comprehension of the physical principles underlying countercurrent exchange helps students to understand how kidneys work and how modifications of a circulatory system can influence the movement of heat or chemicals to promote or minimize exchange and reinforces the concept that heat and chemicals move down their temperature or concentration gradients, respectively. One example of a well-documented countercurrent exchanger is the close arrangement of veins and arteries inside bird legs; therefore, the setup was arranged to mimic blood vessels inside a bird leg, using water flowing inside tubing as a physical proxy for blood flow within blood vessels.
Genetic architecture of complex traits in plants

Genetic architecture refers to the numbers and genome locations of genes that affect a trait, the magnitude of their effects, and the relative contributions of additive, dominant, and epistatic gene effects. Quantitative trait locus (QTL) mapping techniques are commonly used to investigate genetic architectures, but the scope of inferences drawn from QTL studies are often restricted by the limitations of the experimental designs. Recent advances in experimental and statistical procedures, including the simultaneous analysis of QTL that segregate in diverse germplasm, should improve genetic architecture studies. High-resolution QTL mapping methods are being developed that may define the specific DNA sequence variants underlying QTL. Studies of genetic architecture, combined with improved knowledge of the structure of plant populations, will impact our understanding of plant evolution and the design of crop improvement strategies.
Kinematic Wave Modeling in Water Resources

The global hydrologic cycle has received much attention in the last two decades as large-scale environmental issues have moved to the scientific and political centerstage. The key to understanding large-scale hydrologic problems is an adequate knowledge of specific hydrologic process at all scales. In other words, large-scale hydrologic regimes are a reflection of the interaction of individual hydrologic processes as they are integrated across the space-time continuum. Kinematic Wave Modeling in Water Resources makes a nice contribution to the analysis of the surficial, terrestrial, hydrologic cycle, and, in particular, to the interaction between surface and subsurface waters. Although the literature on surface-water hydrology is vast, this book focuses on kinematic wave theory and its application to engineering hydrologic practice. The book also presents a treatment of the modeling of planar flow caused by dam breaks.
An open operating system for a single-user machine

The file system, memory management and program linking facilities of a single-user operating system are described. The main points of interest are the openness of the system, which establishes no sharp boundary between itself and the user's programs, and the techniques used to make the system robust.
Saccadic head rotations during walking in the stalk-eyed fly (Cyrtodiopsis dalmanni)

In stalk-eyed flies (Diopsidae), the eyes are positioned at the end of rigid peduncles protruding laterally from the head. Sexual selection for eye span in male Cyrtodiopsis dalmanni results in eye span that exceeds body length and exceeds the eye span of females. We studied whether the twofold higher moment of inertia (MOI) of the male head results in a reduced head rotation velocity during turning. We analysed films of flies performing walking turns and compared the head kinematics between the sexes. The significance of head rotation to turning was evaluated from the turning kinematics of flies with immobilized (glued) heads. Male and female C. dalmanni rotated their heads relative to the surrounding environment 1.55-fold (male) and 1.65-fold (female) faster than the angular velocity of the body by performing rapid head saccades. During the larger turns, flies with immobilized heads were unable to reorient gaze as fast as the control flies. Despite the larger MOI of the head, male C. dalmanni match the head saccade of females suggesting that eye span elongation is coupled by an adaptation of the neck apparatus to rotate the wider head.
New records of marine choanoflagellates off the Chilean coast

This is the first report of planktonic choanoflagellates from the Chilean coast, relating their abundance with that of bacteria and viruses. Surface water samples were taken off Antofagasta, Montemar, and Puerto Montt and samples from ballast tanks were also analyzed. The choanoflagellates were identified following morphological type descriptions. Viruses and bacteria were stained with SYBR Green and choanoflagellates, bacteria, and viruses were counted simulta - neously using red autofluorescence for the former and green fluorescence for the latter two. Six species of Acanthoecidae were observed for the first time in Chilean waters: Calliacantha multispina (0.3·10 3 L -1 ), Acanthocorbis apoda, Stepha- noeca diplocostata (2.0·10 3 L -1 ), Crinolina isefiordensis , Parvicorbicula superpositus, and Pleurasiga minima (5.0·10 3 L -1 ). The concentrations of bacteria (1.1·10 6 -4.5·10 6 ) and viral-like particles (VLPs) (7.9·10 6 -21·10 6 ) agreed with those typically found in marine coastal waters. In addition, Acanthocorbis asymmetrica was found in ballast waters, where its high concentration (20·10 3 L -1 ) likely resulted from the particular physical and biological environment therein.
Low velocity friction compensation

A model-free design methodology is reported for identification and stable adaptive control of a class of systems with state dependent parasitic effects such as friction. The methodology is constructive, incorporates modeling error bound information, and ensures stable and convergent performance. The identifier and control designs are applicable to a class of low-dimensional dynamic systems with the cited parasitic effects. Validation of the designs is provided using two hardware example cases.
Sagittal-plane trunk position, landing forces, and quadriceps electromyographic activity.

Abstract Context: Researchers have suggested that large landing forces, excessive quadriceps activity, and an erect posture during landing are risk factors for anterior cruciate ligament (ACL) inju...
Variation among populations of Galapagos land iguanas (Conolophus): contrasts of phylogeny and ecology

A phylogenetic scheme derived via multivariate analyses of adaptively neutral scale characteristics is compared to patterns of ecological adaptation in body size and shape, hatchling size, clutch size, and reproductive seasonality, in extant populations of Galapagos land iguanas (genus Conolophus). Three groups of land iguana populations are identified, the oldest being the population of Isla Santa Fe, followed by the populations of the central islands (Santa Cruz, Plaza Sur and Baltra), the youngest populations are those of the western islands (Fernandina and Isabela). Patterns of ecological similarity among these populations are not concordant with phylogenetic lineage. Populations most similar in ecological characteristics are often phylogenetically divergent. Adaptation to local conditions by iguana populations is apparently more important than phylogenetic constraint in explaining variation in ecological characteristics. The assumption that phylogenetically closely-related organisms are also ecologically more similar than less closely-related organisms is not supported by this evidence. Some previous studies may have been misled by using ecological characteristics to derive phylogenetic lineages, resulting in circular support of the assumption.
Nonlinearly Constrained Optimization Using Heuristic Penalty Methods and Asynchronous Parallel Generating Set Search

Many optimization problems are characterized by expensive objective and/or constraint function evaluations paired with a lack of derivative information. Direct search methods such as generating set search (GSS) are well understood and efficient for derivative-free optimization of unconstrained and linearly constrained problems. This paper presents a study of heuristic algorithms that address the more difficult problem of general nonlinear constraints where derivatives for objective or constraint functions are unavailable. We focus on penalty methods that use GSS to solve a sequence of linearly constrained problems, numerically comparing different penalty functions. A classical choice for penalizing constraint violations is � 2 , the squared � 2 norm, which has advantages for derivative-based optimization methods. In our numerical tests, however, we show that exact penalty functions based on the � 1, � 2 ,a nd� ∞ norms converge to good approximate solutions more quickly and thus are attractive alternatives. Unfortunately, exact penalty functions are nondifferentiable and consequently degrade the final solution accuracy, so we also consider smoothed variants. Smoothed-exact penalty functions are attractive because they retain the differentiability of the original problem. Numerically, they are a compromise between exact and � 2 , i.e., they converge to a good solution somewhat quickly without sacrificing much solution accuracy. Moreover, the smoothing is parameterized and can potentially be adjusted to balance the two considerations. Since our
Rural Gaps in Participation in Early Childhood Education

While state government spending on early education has grown in recent years, accessibility of preschool programs for rural children remains a problem. Using census-tract data from a nationally-representative data set on U.S. children, multinomial logit estimation reveals significant differences in early education experiences between rural and nonrural children. Both rural children and children of less-educated mothers are less likely to participate in preschool. This paper concludes by discussing the appropriate role of local, state, or federal governments in funding rural preschool programs. While early educational investments are being touted as effective economic development tools, the nature of the positive externalities associated with preschool makes it unlikely that any single rural community would invest in high-quality programs without state or federal assistance.
An evaluation of BrailleTouch: mobile touchscreen text entry for the visually impaired

We present the evaluation of BrailleTouch, an accessible keyboard for blind users on touchscreen smartphones. Based on the standard Perkins Brailler, BrailleTouch implements a six-key chorded braille soft keyboard. Eleven blind participants typed for 165 twenty-minute sessions on three mobile devices: 1) BrailleTouch on a smartphone; 2) a soft braille keyboard on a touchscreen tablet; and 3) a commercial braille keyboard with physical keys. Expert blind users averaged 23.2 words per minute (wpm) on the BrailleTouch smartphone. The fastest participant, a touchscreen novice, achieved 32.1 wpm during his first session. Overall, participants were able to transfer their existing braille typing skills to a touchscreen device within an hour of practice. We report the speed for braille text entry on three mobile devices, an in depth error analysis, and the lessons learned for the design and evaluation of accessible and eyes-free soft keyboards.
Flexibility: An Attribute of Good Organization

(1968). Flexibility: An Attribute of Good Organization. Hospital Topics: Vol. 46, No. 4, pp. 45-47.
SCREENING OF SURFACE WAVES IN SOILS

Field model tests were performed to determine the effectiveness of trenches in shielding against vibrations transmitted through the ground. In tests designated as active isolation, annular trenches surrounding a vibrating footing were used to reduce the amplitude of vibrations transmitted away from the footing. In tests designated as passive isolation, straight trenches were used as barriers at a distance from a vibrating footing to shield a designated zone. Two indicators of screening effectiveness were studied: (1) The degree of reduction in vibration amplitude, and (2) the shape and extent of the screened zone. In all tests the shallowest trench which provided a prescribed degree of shielding was determined. Trenches were compared on the basis of dimensionless geometrical parameters formed by relating trench dimensions to the wave length of the Rayleigh wave. The relative effectiveness of open trenches and sheet-wall barriers of the same size was also studied.
Oscillatory Diffusion and Second-Order Cyclostationarity in Alanine Tripeptide from Molecular Dynamics Simulation.

Molecular dynamics (MD) simulation distinctly describes motions of biomolecules at high resolution and can potentially be used to explain allosteric mechanism in subcellular processes. Statistical methods are necessary to realize this potential because MD simulations generate a large volume of data and because the analysis is never efficient, objective, or thorough without using appropriate statistical approaches. Tracing the flow of information within a biomolecule requires not only a description of an overall mechanism but also a multiscale statistical description from atomic interactions to the overall mechanism. The foundation of this multiscale description, in general, is a measure of correlation between motions of atoms or residues, as reflected by dynamic cross-correlation, Pearson correlation, or mutual information. However, these correlations can be inadequate because they assume wide sense stationarity, which means that the instantaneous average and correlation of a particular property are time-...
Managing the drug regimens of immigrants from other cultures.

Described as a nation founded by immigrants, the United States still serves as a new home to people from other cultures—people who may view medical care differently than mainstream America does. A clinician’s lack of knowledge of or appreciation for a patient’s culture can hamper efforts to
Comparison of Laser Mass Spectra Obtained at Ambient Conditions vs. Sample Freezing

A significant advantage of laser mass spectrometry (LMS) is its capability to obtain spatial distributions of analytes within organic matrices [1–2]. Our interest in this area has focused on developing LMS for studying organic components within organic matrices. Many systems of interest contain volatile materials not readily suited to LMS analysis [3]. We have utilized two approaches to obtain LM spectra of volatile materials. The first approach uses a cold probe to freeze volatile organics, significantly reducing their vapor pressure. The second employs a thin formvar [poly(vinyl formal)] film as a seal between the sample and the instrument vacuum [3]. Formvar films employed in this manner allow laser mass analysis to be performed at atmospheric pressure; furthermore, no change in the physical state of the sample occurs when using these films. The potential advantage of using formvar lies in the ability to obtain LMS of liquids and solutions as in FAB, whereas, LMS analysis using the cold probe is performed with the samples in the solid state.
Sports Hernia—History and Physical Examination: Making the Diagnosis with Confidence

Sports hernia represents a complex clinical entity that is generally poorly understood and commonly missed by sports medicine clinicians. Patients are typically athletes involved in sports requiring explosive movements with rapid changes in direction, resulting in trunk hyperextension and thigh hyperabduction and resultant shear injury to the hemi-pelvis with pathologic weakening of the posterior inguinal canal. They present with chronic activity-related groin or lower quadrant abdominal pain that is relieved by rest but returns with sport. The discrete diagnosis of sports hernia has been historically difficult to make due to the fact that a number of other musculoskeletal, gastrointestinal, genitourinary, and systemic diagnoses can have a similar presentation. The pathoanatomy of sports hernia, therefore, does not fit perfectly into one medical subspecialty, making it difficult for a single provider to adequately evaluate a patient with activity-related groin pain. Clinicians require not only a high index of suspicion, but also a broad clinical skill set to be able to rule out the numerous other clinical mimickers, and rule in the diagnosis of sports hernia. The goal of this chapter is to assist the clinician in the distillation of what can be a tremendous amount of vague clinical data, into a focused constellation of history and physical exam findings, resulting in the confident diagnosis of this condition.
PHYSICAL PROCESSES AND SEDIMENT FLUX THROUGH REEF-LAGOON SYSTEMS

Studies of physical processes in reef-lagoon systems continue to emphasize the importance of waves and wave-induced currents at the reef crest as agents of sediment transport to backreef environments. These across-the-reef currents are also largely responsible for driving backreef lagoon circulation. Rapid energy transformations associated with the process of wave breaking at the reef crest are responsible for strong reef-normal surge currents. Estimates of energy loss, as determined by wave height changes caused by wave breaking, can be as high as 70-80%' for discontinuous reefs and >90% for continuous examples. The amount of energy loss is related to depth of water over the reef crest, a function of reef topography and tidal regime. Low-tide conditions promote the greatest incident wave modification and attenuation as a result of increased breaking-wave intensity. Under trade-wind conditions found in the Caribbean, surge currents of 50-80 cm/sec for durations of 2-6 sec are common in a low to moderate wave-energy setting (4-6 sec input waves, 40- 50 cm average heights). Sediments through the sand sizes up to pebbles are easily transported lagoonward by these periodic bursts of energy. Flow in shallow backreef lagoons (generally <3 km wide) is driven largely by across-the-reef currents resulting from breaking waves. Long, unbroken reefs tend to induce axial currents in the backreef lagoon which flow roughly parallel to the reef trend. Side-scan sonographs indicate that large bedforms define a region of bottom sediment migration related to strong currents down the lagoon axis, presumably activated during periods of abnormal wave activity on the reef.
DNA Content and Proliferative Activity of Cystosarcoma Phyllodes of the Breast: Potential Prognostic Significance

Predicting the biologic behavior of cystosarcoma phyllodes of the breast by histopathologic examination has been difficult. Flow cytometric DNA and cell cycle analysis was performed for 30 patients with cystosarcoma phyllodes of the breast to determine its potential prognostic utility. Traditional histopathologic parameters and the patients' clinical outcome with a minimum follow-up period of at least five years were also analyzed. Of all the variables examined, DNA ploidy, proliferative index, number of mitoses, and tumor margin were significantly associated with an adverse clinical course. Multivariate regression analysis of the authors' data showed that DNA content was a significant predictor of the patients' clinical outcome. The authors conclude that the DNA ploidy study is a useful, objective adjunct to the clinicopathologic assessment of cystosarcoma phyllodes of the breast.
The Concept of Mass in Intra-urban Shopping:

Does a shopping center hold a uniform appeal for the potential customers that surround it or are various market segments attracted in different degrees? Judging from the models employed to predict ...
Probing the Photoisomerization of CHBr3 and CHI3 in Solution with Transient Vibrational and Electronic Spectroscopy

Transient infrared absorption spectroscopy monitors condensed-phase photodissociation dynamics of 30 mM CHBr3 and 50 mM CHI3 in liquid CCl4. The experiments have picosecond time resolution and monitor the C-H stretch region of both the parent polyhalomethanes and their photolytically generated isomers. The C-H stretching transitions of these isomers, in which the emergent halogen atom returns to form a C-X-X bonding motif, appear about 9 ps after photolysis for iso-CHBr2-Br and in about 46 ps for iso-CHI2-I. These time scales are consistent with, but differ from, the time evolution of the transient electronic absorption spectra of the same samples, highlighting the subtle differences between monitoring the vibrational and electronic chromophores. The specificity of using vibrational transitions to track condensed-phase reaction dynamics permits reassessment of the transient electronic spectrum of photolysis in neat CHBr3, which has an additional prompt feature near 400 nm. Calculations show that this feature, which arises from a precursor to the isomer, is a charge-transfer transition of a contact pair between the nascent Br fragment and a nearby CHBr3 molecule. Dilution and solvent studies show that transition is independent of the solvent. The iso-CHBr2-Br transition wavelength, however, shifts over the range of 400 to 510 nm depending on the solvent. Time-dependent density functional calculations faithfully reproduce these trends.
Releasing and assessment of potential risk for heavy metals from dredging sediment of polluted river in the stacking

The mass ratios of heavy metals in Shuangqiao sediment stack of Chaohu lake and surrounding agricultural region were measured,the existing forms of heavy metals were analyzed by BCR3 sequential extraction procedures,discussing the extent of the release of heavy metals yard.The result illustrates that the amount of chromium,copper and lead emission account to 43.9%,13.6% and 18.2% respectively in the stack;most of heavy metals exist as the residual form.The ecological risks of surrounding agricultural region with these heavy metals were assessed with Hakansons's potential ecological harmfulness index,the results indicate that the ecological harm of Cr,Cu and Pb were marginal.
Housing as a Social Determinant of Health: Exploring the Relationship between Rent Burden and Risk Behaviors for Single Room Occupancy Building Residents

A growing body of health determinants research recognizes that housing and health are intimately linked. This study explores the relationship between rent burden (the ratio of rent to income) and health risk behaviors among a sample of single room occupancy (SRO) building residents. Cross-sectional data were gathered from a sample of 162 residents living in privately owned, for-profit SROs in Chicago. Findings indicated that participants who had full rental subsidies and thus were designated in a no-rent-burden category were more likely to engage in risk behaviors including illicit drug use, having multiple sexual partners, and having sex without a condom, in comparison to participants with moderate or high-rent burdens. These findings suggest that interventions to increase housing stability and affordability and bolster reliable income sources (in addition to rental subsidies) may be key in reducing risk behaviors and improving health for vulnerably housed populations such as SRO residents.
Regulation of p53 oligomerization by Ras superfamily protein RBEL1A.

Our previous studies showed that RBEL1A overexpressed in multiple human malignancies and its depletion by RNAi caused severe growth inhibition in tumor cells. We also showed that RBEL1A directly interacted with p53 and such interactions occurred at the oligomeric domain of p53. However, the effect of such interactions on p53 oligomerization and function remained to be investigated. Here, we report that the interaction of RBEL1A and p53 suppressed p53 oligomer formation in unstressed cells and in cells exposed to DNA damage. Furthermore, purified RBEL1A blocked the oligomerization of recombinant p53 corresponding to residues 315-360 in vitro. RBEL1A also significantly reduced the oligomerization of the exogenously expressed C-terminal region (residues 301-393) of p53 in cells. Overexpression of RBEL1A (as seen in human tumors), also suppressed oligomerization by endogenous p53. Our results also showed that GTPase domain of RBEL1A at residues 1-235 was sufficient to block p53 oligomerization. Furthermore, silencing of endogenous RBEL1A significantly enhanced the formation of p53 oligomeric complex following ultraviolet radiation-mediated DNA damage and RBEL1A knockdown also enhanced expression of p53 target genes. Taken together, our studies provide important new molecular insights into the regulation of p53 and the oncogenic role of RBEL1A in the context to human malignancy. Implications Elevated RBEL1A expression in human tumors could negatively regulate p53 by inhibiting its tetramerization.
An Investigative Model to Explain Unhealthy Food and Beverage Purchase Intentions

The competitive food marketing industry is fueled by demands of consumer constituencies to include processed or, alternatively, organic foods and beverages in their diet. Portrayals in the media further distinguish these two views. Linked to the processed food and beverage adherent and particular to our research, corn-fed beef and soft drinks made with artificial sugar offer consumers paltry health benefits. As both corn-fed beef and soft drinks are copiously offered in the food and beverage industry, we use these unhealthy food and beverage options as outcome variables in our proposed model.