cssi/SciSciGPT-SciSciNet huggingface dataset:
Local-scale variability of seepage and hydraulic conductivity in a shallow gravel-bed river

Seepage rate and direction measured with a seepage metre modified for use in flowing water were greatly variable along a 300-m reach of a shallow, gravel-bed river and depended primarily on the local-scale bed topography. The median value of seepage measured at 24 locations was 24 cm/day, but seepage measured at specific sites ranged from −340 to +237 cm/day. Seepage also varied substantially over periods of hours to days and occasionally reversed direction in response to evolution of the sediment bed. Vertical hydraulic conductivity was related to seepage direction and was larger during upward seepage than during downward seepage; with differences ranging from 4 to 40% in areas of active sediment transport to more than an order of magnitude in areas where current was too slow to mobilize bed sediment. Seepage was poorly related to hydraulic gradient measured over vertical distances of 0·3 m and appeared to be opposite the hydraulic gradient at 18% of the locations where both parameters were measured. Results demonstrate the scale dependence of these measurements in coarse-grained hyporheic settings and indicate that hydraulic gradients should be determined over a much shorter vertical increment if used to indicate exchange across the sediment–water interface. Published in 2009 by John Wiley & Sons, Ltd.
Effects of predation risk on habitat selection by water column fish, benthic fish and crayfish in stream pools

Predation risk can affect habitat selection by water column stream fish and crayfish, but little is known regarding effects of predation risk on habitat selection by benthic fish or assemblages of fish and crayfish. I used comparative studies and manipulative field experiments to determine whether, (1) habitat selection by stream fish and crayfish is affected by predation risk, and (2) benthic fish, water column fish, and crayfish differ in their habitat selection and response to predation risk. Snorkeling was used to observe fish and crayfish in, (1) unmanipulated stream pools with and without large smallmouth bass predators (Micropterus dolomieui >200 mm total length, TL) and (2) manipulated stream pools before and after addition of a single large smallmouth bass, to determine if prey size and presence of large fish predators affected habitat selection. Observations of microhabitat use were compared with microhabitat availability to determine microhabitat selection. Small fish (60–100 mm TL, except darters that were 30–100 mm TL) and crayfish (40–100 mm rostrum to telson length; TL) had significantly reduced densities in pools with large bass, whereas densities of large fish and crayfish (> 100 mm TL) did not differ significantly between pools with and without large bass. Small orangethroat darters (Etheostoma spectabile), northern crayfish (Orconectes virilis), and creek chubs (Semotilus atromaculatus) showed significantly greater densities in pools without large bass. The presence of large smallmouth bass did not significantly affect depths selected by fish and crayfish, except minnows, which were found significantly more often at medium depths when bass were present. Small minnows and large and small crayfish showed the greatest response to additions of bass to stream pools by moving away from bass locations and into shallow water. Small darters and sunfish showed an intermediate response, whereas large minnows showed no significant response to bass additions. Response to predation risk was dependent on prey size and species, with preferred prey, crayfish and small minnows, showing the greatest response. Small benthic fish, such as darters, are intermediate between small water column fish and crayfish and large water column fish in their risk of predation from large smallmouth bass.
Likelihood-look-ahead inference on the equilibrium distribution of Markov chains

We propose a method for statistical inference on the stationary probability measure of a Markov chain with general state space whose transition function belongs to a parametric family. We extend the look-ahead method introduced by Glynn and Henderson to this situation, using maximum likelihood estimation based on data from the observed process. We show the consistency and asymptotic normality of our estimator and construct confidence intervals for the values of the stationary distribution. We illustrate our results with simulation studies of the Lindley process and the AR(1) process.
Recombinant Bacillus anthracis spore proteins enhance protection of mice primed with suboptimal amounts of protective antigen

Inactivated Bacillus anthracis spores given with protective antigen (PA) contribute to immunity against anthrax in several animal models. Antiserum raised against whole irradiated B. anthracis spores has been shown to have anti-germination and opsonic activities in vitro. Based on these observations, we hypothesized that surface-exposed spore proteins might serve as supplemental components of a PA-based anthrax vaccine. The protective anti-spore serum was tested for reactivity with recombinant forms of 30 proteins known, or believed to be, present within the B. anthracis exosporium. Eleven of those proteins were reactive with this antiserum, and, subsequently a subset of this group was used to generate rabbit polyclonal antibodies. These sera were evaluated for recognition of the immunogens on intact spores generated from Sterne strain, as well as from an isogenic mutant lacking the spore surface protein Bacillus collagen-like antigen (BclA). The data were consistent with the notion that the antigens in question were located beneath BclA on the basal surface of the exosporium. A/J mice immunized with either the here-to-for hypothetical protein p5303 or the structural protein BxpB, each in combination with subprotective levels of PA, showed enhanced protection against subcutaneous spore challenge. While neither anti-BxpB or anti-p5303 antibodies reduced the rate of spore germination in vitro, both caused increased uptake and lead to a higher rate of destruction by phagocytic cells. We conclude that by facilitating more efficient phagocytic clearance of spores, antibodies against individual exosporium components can contribute to protection against B. anthracis infection.
Assessing Cultural Competence of Policy Organizations

Assessment of the capabilities of human service providers to care for individuals from diverse cultures has been widely discussed in the literature. However, a less examined area is the appraisal of the cultural competence of the administrative or policy bodies whose actions shape the character of these human services. This article demonstrates an approach for evaluating a policy organization's cultural competence using a governmental agency as a case study. Findings from this assessment prompted this agency to generate plans to further enhance its cultural competence.
The Complex of Ethidium Bromide with Genomic DNA: Structure Analysis by Polarized Raman Spectroscopy

Structural properties of the complex formed between genomic DNA and the intercalating drug ethidium bromide (EtBr) have been determined by use of a Raman microscope equipped with near-infrared laser excitation. The polarized spectra, which were obtained from oriented fibers of the EtBr:DNA complex, are interpreted in terms of the relative orientations of the phenanthridinium ring of EtBr and bases of DNA. Quantification of structure parameters of EtBr and DNA in the complex were assessed using Raman tensors obtained from polarized Raman analyses of oriented specimens of EtBr (single crystal) and DNA (hydrated fiber). We find that the phenanthridinium plane is tilted by 35 ± 5° from the plane perpendicular to the fiber (DNA helix) axis. Assuming coplanarity of the phenanthridinium ring and its immediate base neighbors at the intercalation site, such bases would have a tilt angle closer to that of A-DNA (20°) than to that of B-DNA (6°). The average base tilt in stretches of DNA between intercalation sites remains that of B-DNA.
A comparative study on methods of optimal sample preparation for the analysis of oligonucleotides by matrix-assisted laser desorption/ionization mass spectrometry.

Metal adducts (e.g., Na+ and K+) significantly hinder the analysis of oligonucleotides by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Although a number of sample purification methods exist, to date no comparative study exists to determine the most efficient method for purifying oligonucleotides. The objective of this work was to perform such a study. Several different oligonucleotide samples were synthesized. Aliquots of these samples were then purposely contaminated with sodium acetate to generate representative contaminated (salted) oligonucleotide samples. A number of popular oligonucleotide purification techniques were then tested as to their effectiveness at removing Na+ from the salted samples. The effectiveness of Na+ removal was qualitatively assessed by comparing the MALDI mass spectra of the original sample, the salted sample, and the salted sample after purification. Micropipet tips packed with C18 reversed-phase packing material (e.g., Zip Tips) appear to be the most effective means of purifying the oligonucleotides investigated. Minidialysis was found to be an effective alternative for purifying higher molecular weight oligonucleotides (>10000 u).
On lq estimation of sparse inverse covariance.

Recently, major attention has been given to penalized log-likelihood estimators for sparse precision (inverse covariance) matrices. The penalty is responsible for inducing sparsity, and a very common choice is the convexl1 norm. However, it is not always the case that the best estimator is achieved with this penalty. So, to improve sparsity and reduce biases associated with thel1 norm, one must move to non-convex penalties such as thelq (0 q < 1). In this paper we introduce the resulting non-concave lq penalized log-likelihood problem, and derive the corresponding optimality conditions. A novel cyclic descent algorithm is presented for penalized log-likelihood optimization, and we show how the derived conditions can be used to reduce algorithm computation. We illustrate by comparing reconstruction quality over the range 0 q 1 for several experiments.
Clinical excellence, but too high a cost: the Metropolitan Life Insurance Company Visiting Nurse Service (1909-1953).

In the winter of 1909, Metropolitan Life Insurance Company, a large company within the private sector, identified visiting nurses as a means of lowering mortality rates, while improving the image of the company. Although initially associated with the nurses of Lillian Walds Henry Street Settlement House, the Metropolitan Visiting Nurse Service eventually formed an alliance with over 650 Visiting Nurse Associations across the United States, caring for over 30 million policy holders. The purpose of this historical research was to analyze the liaison between business and the profession of nursing, identifying factors that served as an impetus for the origin, growth, and decline of the Metropolitan Visiting Nurse Service. Data were gathered in the Metropolitan Life Insurance Company Archives; the Visiting Nurse Association Archives of New York and Chicago; the New York Public Library; Chicago Historical Society; Schlesinger Library at Radcliffe College in Cambridge, MA; Haven Emerson Public Library in New York; National League for Nursing Education Historical Collection in New York; Walter Library, University of Minnesota, Minneapolis, MN; American Public Health Association Historical Collection, Washington, DC; and Special Collection of Virginia Commonwealth University in Richmond, VA. The results indicate that visiting nurses were masters of improvisation, demonstrating clinical excellence under demanding conditions. Although both nursing and business leaders demanded efficiency, nursing focused on quality of nurses, while business viewed cost of a nursing visit as the priority. Unfortunately for the profession, increased educational sources for nurses coupled with declining volume of visits drove the cost of a nursing visit higher than Metropolitan was willing to pay. Consequently, in 1950 Metropolitan made the decision to terminate the service. In a time when the nursing profession seeks both clinical excellence and cost containment, this study uses the past to stimulate questions about the future: Can the nursing profession provide quality care in an era where cost of care is emphasized? Can the profession use the knowledge and principles of the business world to reach mutually satisfying goals of quality patient care and cost effectiveness? Can nursing balance the values inherent in achieving a cost/care attitude?
Native gallium adatoms discovered on atomically-smooth gallium nitride surfaces at low temperature.

In advanced compound semiconductor devices, such as in quantum dot and quantum well systems, detailed atomic configurations at the growth surfaces are vital in determining the structural and electronic properties. Therefore, it is important to investigate the surface reconstructions in order to make further technological advancements. Usually, conventional semiconductor surfaces (e.g., arsenides, phosphides, and antimonides) are highly reactive due to the existence of a high density of group V (anion) surface dangling bonds. However, in the case of nitrides, group III rich growth conditions in molecular beam epitaxy are usually preferred leading to group III (Ga)-rich surfaces. Here, we use low-temperature scanning tunneling microscopy to reveal a uniform distribution of native gallium adatoms with a density of 0.3%–0.5% of a monolayer on the clean, as-grown surface of nitrogen polar GaN(0001) having the centered 6 × 12 reconstruction. Unseen at room temperature, these Ga adatoms are strongly bound to th...
Size Distributions of Precipitation Particles in Frontal Clouds.

Abstract Measurements of the size spectra of precipitation particles have been made with Particle Measuring Systems probes aboard an aircraft flying through frontal clouds as part of the CYCLES (Cyclonic Extra-tropical Storms) PROJECT. These measurements were obtained while the aircraft flew through the clouds associated with mesoscale rainbands at temperatures ranging from −42 to +6°C. Particles ≳1.5 mm in diameter closely follow an exponential size distribution. Above the melting level precipitation occurs mainly in the form of ice particles. In this region the mean particle size of the exponential distribution increases with increasing temperature, indicating that the ice particles grow as they drift downward. The variance of the exponential distribution also increases with increasing temperature above the melting level, indicating that the particles grow particularly well by collection as they fall at various speeds. Passage of the failing particles through the melting level is accompanied by a sudden...
Nourishing women: toward a feminist political ecology of community supported agriculture in the United States

This article examines the motivations of women farmers actively involved in community supported agriculture. Drawing from interviews with farmers situated in a metropolitan region of the USA, it argues that these women's motivations are expressive of an ethics of care that defines their work as centered upon nourishing themselves and others. Women came to this work as a conscious choice to change their life-work. These choices are shaped by the urban context of their farming practices and also by their race and middle class status. These motivations and choices express a care ethics centered in self-care. Drawing from Foucault's ethics of self-care, these motivations express a liberatory transformation of self that is also radically responsible to others and expressive of a post-capitalist politics. These ethically informed agricultural practices correspond to the development of a post-capitalist politics that challenges neoliberal subject formation in food production and consumption. Feminist care ethics...
Analysis of serial–parallel systems in the framework of fuzzy/possibility approach. Part I. Appraisal: case of independent components

Abstract This paper attempts to review the fuzzy/possibility tools when dealing with reliability of serial–parallel systems. Various issues of reasoning-based approaches in this framework are reviewed and discussed and compared with the standard probabilistic approach of reliability. Typically in all the approaches investigated in this paper we adopt a fuzzy probability modelling of a reliability of a single unit. This translates the fact that the precise value of the (probabilistic) reliability of a given unit is rather ill known and, therefore, we attach a possibility distribution on a probability space that accounts for this lack of knowledge. Basically, three based methodologies are discussed and investigated: extension principle-based approach, set theoretic approach and join and meet-based reasoning. Each of these methodologies supports a special description and understanding of the behaviour of the redundancy and/or serial connection. Incidence on other forms of uncertainty like imprecision of the outcome as well as consistency with respect to probabilistic outcomes will be examined.
Convergence to Stochastic Integrals for Dependent Heterogeneous Processes

This paper provides conditions to establish the weak convergence of stochastic integrals. The theorems are proved under the assumption that the innovations are strong mixing with uniformly bounded 2-h moments. Several applications of the results are given, relevant for the theories of estimation with I(1) processes, I(2) processes, processes with nonstationary variances, near-integrated processes, and continuous time approximations.
Networked information management

Every day millions of people trawl the Internet for information using any one of a dozen or more different search tools. Whether they find what they are looking for may depend not only on their skill, but also on their luck. In the corporate arena, organisations are making increasing amounts of information available via intranets. This paper looks at the limitations of current networked information management technology, in particular, shortcomings in the areas of retrieving, organising and sharing of information, and an information management process which would overcome these problems is described. The representation of a user‘s information needs and interests in a user profile is seen to be central to the process and work in this area, including a novel, non-explicit approach to the representation of profiles is covered. Four information access systems developed at BT Laboratories are discussed and the extent to which these are currently able to support the information management process is considered.
PortSec: Port Security Risk Management and Resource Allocation System

Abstract Ports are important to the US economy. This is particularly true with the Ports of Los Angeles and Long Beach (POLA/LB). Over 40% of all containers shipped in and out of the US flow through the two-port complex. In addition, the POLA/LB complex support large bulk cargo, tanker, and cruise ship operations. It is vital that these ports be protected from terrorist attack and/or from damage from natural causes. The DHS funded Center for Risk and Economic Analysis of Terrorism Events (CREATE) is developing a port security risk management and resource allocation system (PortSec). PortSec will support both tactical day-to-day security decision-making and long-term strategic security planning. An initial PortSec prototype (1.0) that supports tactical day-to-day risk assessment and resource allocation has been developed and demonstrated to the POLA/LB and the DHS Science & Technology Directorate.
The 3He(p, 2p)pn reaction at 35 MeV

Abstract The differential cross sections for the reaction 3 He(p, 2p)pn were measured at 35 MeV for the angular sets 35°–35°; 40°–40°; 45°–45°; 42°–30°; 45°-35°; 70°-35°. The data were compared to four-body phase-space calculations. Several deviations from the phase-space predictions were observed but no conclusive evidence for excited states in 3 He was found.
Mosaic diamond substrates approaching single-crystal quality using cube-shaped diamond seeds

Abstract Large-area (approximately 1 cm 2 ) mosaic diamond substrates were obtained by orienting smaller (250 μm on a side) diamond cubes and fusing them homoepitaxially. The orientation starts by distributing a single layer of several hundred cubes on a smooth substrate. The cubes are then wetted with a mixture of isopropyl alcohol and glycerin, whose surface tension causes the cubes to coalesce into domains consisting of 20–30 cubes. The cubes in each domain have the same crystallographic orientation, but the domains are randomly oriented to each other. Two techniques were found to produce consistent orientation of the domains. One technique is to orient the domains physically against to 1 mm high, vertical, square walls on the substrate. The other technique is to push physically on the layer of cubes, which deforms the domains causing them to rotate and form a layer with consistent orientation. After the layer of cubes is oriented, homoepitaxial diamond is grown on it to obtain a continuous mosaic substrate. Depending on the techniques used, orientation with a standard deviation from 1° to 5° can be achieved.
Biopolymers in drug technology: the use of DNA in purifying phleomycin.

It is sometimes easier and cheaper to extract a drug's target sites from cells than it is to purify, concentrate or manufacture the drug itself. This is especially true in the case of DNA and some of the exotic antibiotics that react with it. Phleomycin, an inhibitor of replication, was considered as a specific case in point. Biologically active components of this antibiotic mixture bind nondestructively to DNA, in vitro and in vivo, and thereafter may be processed by simple, economical methods usually reserved to macromolecules of much greater size.
Abstract A28: Impact of macrophage function on the efficacy of radiation therapy

In patients with locally advanced breast cancer, radiation therapy (RT) and chemotherapy following surgery has been a mainstay of treatment for breast cancer with demonstrated survival advantage in numerous randomized trials. However, despite recent advances in treatment, many women still ultimately succumb to this disease highlighting the need to improve our therapeutic options. Previous work from other groups demonstrated that the therapeutic effects of RT depend in part on activation of the immune system, but little is known about the details of this activation. To address this, we explored the effects of RT on the immune microenvironment in a syngeneic orthotopic murine transplantation model of breast cancer and found that 7 days following RT tumors had significantly increased numbers of CD11b+ macrophages compared to untreated tumors. When we depleted these macrophages using a CSF1 inhibitor or CSF1 blocking Ab following RT we found significantly delayed tumor growth compared to RT alone. Tumor-associated macrophages (TAMs) are key orchestrators of the tumor microenvironment and can be either classically-activated expressing cytotoxic molecules leading to tumor cell death (“anti-tumor”) or alternatively-activated in which they secrete proangiogenic, prosurvival, and proinvasive factors that foster tumor progression (“pro-tumor”). Given the delayed growth when TAMs were depleted following RT, we hypothesized that the infiltrating TAMs are predominantly of the pro-tumor phenotype and that a milieu that favors an anti-tumor phenotype would enhance the effect of RT. We tested this hypothesis using a blocking antibody against IL-4, the predominant cytokine which drives the alternatively-activated phenotype, and we observed significantly reduced tumor growth in mice treated with the combination of RT and IL-4 blockade compared to mice treated with either agent alone. These studies indicate that infiltrating macrophages following RT have a protumor function, and that conversion of these macrophages to a cytotoxic phenotype may improve the efficacy of RT. Citation Format: Stephen L. Shiao, David G. DeNardo, Bruce A. Faddegon, David M. Underhill, Catherine C. Park, Lisa M. Coussens. Impact of macrophage function on the efficacy of radiation therapy. [abstract]. In: Abstracts: AACR Special Conference on Cellular Heterogeneity in the Tumor Microenvironment; 2014 Feb 26-Mar 1; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(1 Suppl):Abstract nr A28. doi:10.1158/1538-7445.CHTME14-A28
An econometric model of the Kenyan economy

Abstract This paper presents a description of a macroeconomic model of the Kenyan economy. The model has been constructed to describe a developing country which is small and open and which is affected by conditions in world commodity and credit markets. The theoretical structure of the model, which consists of markets for domestic output, labour, money and the balance of payments, is described. A complete listing of the model with numerical results of the equation estimation follows. Finally, forecasting properties and examples of simulations are mentioned.
Adaptive Circuit Design Using Independently Biased Back-Gated Double-Gate MOSFETS

A new adaptive circuit design approach is proposed and analyzed employing independently biased back-gated Double-Gate MOSFET (DGMOSFET) devices. Threshold voltage tuning using back-gate of the DGMOSFET was compared with a conventional body-bias method. The technique is a promising solution to control the transistor's threshold voltage while reducing undesirable effects at the sub-50-nm device technology nodes. An automatic adaptive circuit for threshold voltage tuning was implemented using DGMOSFET devices in 45 nm CMOS technology. Simulation results show that this circuit compensates for static and dynamic variations. This adaptation approach using DGMOSFETs along with adaptive supply voltage scaling allows simultaneous optimization of power and performance according to application-specific workload and requirements. Simulation results using a 45 nm CMOS technology indicate that this adaptive circuit design can provide 50% higher performance for the same energy, or consume 40% less energy for the same performance. In contrast to conventional methods which only employ dynamic voltage scaling, adaptive tuning of threshold voltages reduces power consumption while maintaining its noise margin.
An iterative EPID calibration procedure for dosimetric verification that considers the EPID scattering factor

There has been an increasing interest in the application of electronic portal imaging devices (EPIDs) to dosimetric verification, particularly for intensity modulated radiotherapy. Although not water equivalent, the phantom scatter factor of an EPID, Spe, is generally assumed to be that of a full phantom, Sp, a slab phantom, Sps, or a mini phantom. This assumption may introduce errors in absolute dosimetry using EPIDs. A calibration procedure that iteratively updates Spe and the calibration curve (pixel value to dose rate) is presented. The EPID (Varian Portal Vision) is irradiated using a 20 x 20 cm2 field with different beam intensities. The initial guess of dose rates in the EPID is calculated from ionization chamber measurements in air, multiplied by Sp or Sps. The calibration curve is obtained by fitting EPID readings from pixels near the beam central axis and dose rates in EPID to a quadratic equation. The Spe is obtained from EPID measurements in 10 X 10 cm2 and 20 x 20 cm2 field and from the calibration curve, and is in turn used to adjust the dose rate measurements and hence the calibration curve. The above procedure is repeated until it converges. The final calibration curve is used to convert portal dose to dose in the slab phantom, using the calibrated Spe, or assuming Spe = Sp or Spe=Sps . The converted doses are then compared with the dose measured using an ionization chamber. We also apply this procedure to off-axis points and study its dependence on the energy spectrum. The hypothesis testing results (on the 95% significance level) indicate that systematic errors are introduced when assuming Spe = Sp or Spe=Sps and the dose calculated using Spe is more consistent with ionization chamber measurements. Differences between Spe and Sps are as large as 2% for large field sizes. The measured relative dose profile at dmax using the EPID agrees well with the measured profile at dmax of the isocentric plane using film in a polystyrene phantom with full buildup and full backup, for open and wedged fields, and for a broad range of field sizes of interest. The dependence of the EPID response on the energy spectrum is removed once the calibration is performed under the same conditions as the actual measurements.
Patient Comprehension of an Interactive, Computer-Based Information Program for Cardiac Catheterization: A Comparison With Standard Information

Background Several studies suggest that standard verbal and written consent information for treatment is often poorly understood by patients and their families. The present study examines the effect of an interactive computer-based information program on patients' understanding of cardiac catheterization. Methods Adult patients scheduled to undergo diagnostic cardiac catheterization (n = 135) were randomized to receive details about the procedure using either standard institutional verbal and written information (SI) or interactive computerized information (ICI) preloaded on a laptop computer. Understanding was measured using semistructured interviews at baseline (ie, before information was given), immediately following cardiac catheterization (early understanding), and 2 weeks after the procedure (late understanding). The primary study outcome was the change from baseline to early understanding between groups. Results Subjects randomized to the ICI intervention had significantly greater improvement in understanding compared with those who received the SI (net change, 0.81; 95% confidence interval, 0.01-1.6). Significantly more subjects in the ICI group had complete understanding of the risks of cardiac catheterization (53.6% vs 23.1%) ( P = .001) and options for treatment (63.2% vs 46.2%) ( P = .048) compared with the SI group. Several predictors of improved understanding were identified, including baseline knowledge ( P P = .002), and use of the ICI ( P = .003). Conclusions Results suggest that an interactive computer-based information program for cardiac catheterization may be more effective in improving patient understanding than conventional written consent information. This technology, therefore, holds promise as a means of presenting understandable detailed information regarding a variety of medical treatments and procedures.
Cavernous Sinus Thrombosis: Report of Case

A case of cavernous sinus thrombosis is discussed to show how the dentist must be able to diagnose possible complications secondary to dental surgical procedures and to treat or refer a patient before a life-threatening situation develops.
A cost-effective two-step method for enhancing the hydrophilicity of PDMS surfaces

Poly(dimethylsiloxane) (PDMS) is commonly used for fabricating micro- and nanofluidic devices due to its low cost and ease of fabrication. The major disadvantage to using PDMS for these applications is its hydrophobic properties. The current methods that enhance the hydrophilicity of elastomers used for micro- and nanofluidic applications are intricate and cost-inefficient. This contribution demonstrates how the hydrophobic PDMS surface can be chemically modified in 5 minutes using a two-step silanization method in an oxygen-saturated environment to provide a highly stable hydrophilic surface for irreversible PDMS to PDMS bonding and PDMS to borosilicate glass bonding. The surface wettabilities of the modified and pristine PDMS were characterized over a wide range of time using static contact angle measurements. The modified PDMS surfaces exhibit enhanced stable hydrophilicity with a contact angle of 87° for 5 days. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectra of the modified and pristine PDMS surfaces confirmed the presence of hydroxyl groups of water molecules in the modified PDMS at 3150 cm−1 in addition to the characteristic peaks of pristine PDMS. This reliable silane beaker chemistry-based method allows easy bonding of the PDMS surfaces for liquid containment and irreversible bonding to borosilicate glass. This approach can effectively be adapted for enhancing the hydrophilicity of PDMS, which ensure relevance for current and future micro- and nanofluidic applications.
Nano Fracture Chemical Sensor for Explosives Detection

Selective detection of explosive compounds is critical for national defense and homeland security. In this paper we describe the fabrication and demonstration of a chemical sensor capable of detecting nitroaromatic explosives in air. The device has the unique features of nano-scale dimensions, simple and inexpensive fabrication, and low power consumption. It consists of a nano-patterned conductive metal line placed on top of a patterned responsive polymer, poly(4-vinylpyridine) (P4VP). Due to polymer-solvent interactions, P4VP swells when it encounters the target analyte, producing a large stress. Detection takes place by monitoring the change in device resistance as the metal nano line deforms or fractures when P4VP swells and transfers mechanical stress. The sensors would be ideal for discreet, wide-scale deployment over large areas. It is also important to note that device sensitivity can be readily enhanced by scaling down the feature size of the metal line or adjusting the material properties of both the metal and polymer. The fabrication process is readily transferrable to a variety of organic and metal materials, improving the versatility of the sensors. The resulting devices may provide new ways to detect security threats and complement existing complex methods to increase the probability of detection and to reduce false alarms. The same approach may also be applicable outside the military/security domain, for example, for pollution monitoring, for factory safety and operational monitoring, or for food quality inspection; all these applications are contingent upon finding the appropriate polymers for the respective analytes.© 2010 ASME
Hazards regression analysis for length-biased data

SUMMARY Length-biased sampling is frequently a convenient technique for the collection of positive-valued or lifetime data. Estimation procedures based on pseudo-likelihood are developed under the proportional hazards model for length-biased data. Bias-adjusted risk set sampling is used for the construction of the pseudo-likelihood and the risk set sampling is replicated to improve estimation performance. The average of the resulting likelihood estimators is taken as the estimator for the regression coefficients. Although the replication procedure is expected to improve estimation accuracy when the sample size is small or moderate, it does not increase the asymptotic efficiency for estimating the regression coefficient. An estimator for the baseline survival function is also presented. It reduces to the maximum likelihood estimator when the regression parameter in the proportional hazards model is zero. Statistical properties of the proposed estimation procedures are developed. Examples are presented to illustrate the methods.
Surveying the Natural Wealth of the World

Although prepared in its original Spanish-language version primarily as a natural resources training aid for Latin America and available since mid-1970 in the English language, this publication has not received the wider attention it deserves. The Case book is a compendium based on the 6 years of experience of a team of specialists in the Organization of American States (OAS) engaged in the design and execution of development-oriented surveys of natural re sources. Unquestionably, the Case book has wide applicability through out the developing world, as well as in the developed countries, among those concerned with project design for integrated natural resources surveys and development.
Gbx2 and Fgf8 are sequentially required for formation of the midbrain-hindbrain compartment boundary

In vertebrates, the common expression border of two homeobox genes, Otx2 and Gbx2, demarcates the prospective midbrain-hindbrain border (MHB) in the neural plate at the end of gastrulation. The presence of a compartment boundary at the MHB has been demonstrated, but the mechanism and timing of its formation remain unclear. We show by genetic inducible fate mapping using a Gbx2CreER knock-in mouse line that descendants of Gbx2+ cells as early as embryonic day (E) 7.5 do not cross the MHB. Without Gbx2, hindbrain-born cells abnormally populate the entire midbrain, demonstrating that Gbx2 is essential for specifying hindbrain fate. Gbx2+ and Otx2+ cells segregate from each other, suggesting that mutually exclusive expression of Otx2 and Gbx2 in midbrain and hindbrain progenitors is responsible for cell sorting in establishing the MHB. The MHB organizer gene Fgf8, which is expressed as a sharp transverse band immediately posterior to the lineage boundary at the MHB, is crucial in maintaining the lineage-restricted boundary after E7.5. Partial deletion of Fgf8 disrupts MHB lineage separation. Activation of FGF pathways has a cell-autonomous effect on cell sorting in midbrain progenitors. Therefore, Fgf8 from the MHB may signal the nearby mesencephalic cells to impart distinct cell surface characteristics or induce local cell-cell signaling, which consequently prevents cell movements across the MHB. Our findings reveal the distinct function of Gbx2 and Fgf8 in a stepwise process in the development of the compartment boundary at the MHB and that Fgf8, in addition to its organizer function, plays a crucial role in maintaining the lineage boundary at the MHB by restricting cell movement.
Islet cell transplantation.

An estimated 177 million people worldwide suffer from diabetes. Insulin administration controls the day-to-day problems of this disease but glucose homeostasis is not fully normalized with insulin replacement and the long-term complications caused by suboptimal homeostasis are significant. In terms of transplantation, two options exist: whole organ pancreas transplant and isolated islet cell transplant. Whole organ transplantation is favored in patients who also need kidney transplantation or have exocrine deficiency. Islet cell transplantation is usually reserved for patients with brittle diabetes and hypoglycemic unawareness. In this latter group of patients, this procedure can be lifesaving. Additionally, it has a profound beneficial effect on quality of life and secondary complications of diabetes such as neuropathy and nephropathy.
The 3-dB transcoding penalty in digital cellular communications

In spite of the widespread attention to data and video, voice is still responsible for up to 75% of the revenue in wireless communications systems today. An unfortunate characteristic of 2nd and 3rd generation digital cellular systems has been the need to transcode at most network interfaces, since the voice codec at the other end of the call is usually unknown and cannot be negotiated. Fourth generation systems such as LTE also require transcoding when the call leaves the LTE network. Transcoding at network interfaces adds complexity, degrades quality, and increases latency, all of which directly impact the quality and cost of voice communications. We investigate the issues in voice communications over tandem connections of wireline and wireless communications links using rate distortion theoretic results and speech coding studies and show that each transcoding operation can incur a 3-dB penalty in source coding performance, in addition to increased latency and complexity. Suggestions for addressing this performance loss are presented.
Overview of Proteasome Inhibitor-Based Anti-cancer Therapies: Perspective on Bortezomib and Second Generation Proteasome Inhibitors versus Future Generation Inhibitors of Ubiquitin-Proteasome System

Over the past ten years, proteasome inhibition has emerged as an effective therapeutic strategy for treating multiple myeloma (MM) and some lymphomas. In 2003, Bortezomib (BTZ) became the first proteasome inhibitor approved by the U.S. Food and Drug Administration (FDA). BTZ-based therapies have become a staple for the treatment of MM at all stages of the disease. The survival rate of MM patients has improved significantly since clinical introduction of BTZ and other immunomodulatory drugs. However, BTZ has several limitations. Not all patients respond to BTZ based therapies and relapse occurs in many patients who initially responded. Solid tumors, in particular, are often resistant to BTZ. Furthermore, BTZ can induce dose-limiting peripheral neuropathy (PN). The second generation proteasome inhibitor Carfizomib (CFZ; U.S. FDA approved in August 2012) induces responses in a minority of MM patients relapsed from or refractory to BTZ. There is less PN compared to BTZ. Four other second-generation proteasome inhibitors (Ixazomib, Delanzomib, Oprozomib and Marizomib) with different pharmacologic properties and broader anticancer activities, have also shown some clinical activity in bortezomib-resistant cancers. While the mechanism of resistance to bortezomib in human cancers still remains to be fully understood, targeting the immunoproteasome, ubiquitin E3 ligases, the 19S proteasome and deubiquitinases in pre-clinical studies represents possible directions for future generation inhibitors of ubiquitin-proteasome system in the treatment of MM and other cancers.
Quantitative Measurement of Toll-like Receptor 4 Agonists Adsorbed to Alhydrogel® by Fourier Transform Infrared-Attenuated Total Reflectance Spectroscopy

ABSTRACT Aluminum salts have a long history as safe and effective vaccine adjuvants. In addition, aluminum salts have high adsorptive capacities for vaccine antigens and adjuvant molecules, for example, Toll-like receptor 4 (TLR4) agonists. However, the physicochemical properties of aluminum salts make direct quantitation of adsorbed molecules challenging. Typical methods for quantifying adsorbed molecules require advanced instrumentation, extreme sample processing, often destroy the sample, or rely on an indirect measurement. A simple, direct, and quantitative method for analysis of adsorbed adjuvant molecules is needed. This report presents a method utilizing Fourier transform infrared spectroscopy with a ZnSe-attenuated total reflectance attachment to directly measure low levels (
Speculations on ataxia-telangiectasia: defective regulation of the immunoglobulin gene superfamily

In this short article, Raymond Peterson and Jane Funkhouser develop the argument that the common molecular mechanism linking the various clinical manifestations of ataxia-telangiectasia (AT) is a defect in the regulation of the immunoglobulin (Ig) gene superfamily. They propose that the AT gene codes for a protein essential for the orderly expression of this gene family, perhaps regulating the gene rearrangement process that appears to be a unique characteristic of this system. Members of the Ig gene superfamily play a major role in the development and operation of the immune and nervous systems, and any perturbation of their expression would be anticipated to produce a panoply of signs and symptoms, such as those characterizing the AT phenotype.
Renegotiation‐proof Labour and Credit Contracts with Worker Mobility

This paper investigates the interaction between a privately informed firm’s contracts for labour and its contracts for credit. The analysis shows that if the worker has no ex post outside opportunities, or if the liquidation value of the firm is large, then the credit contract can always be state-independent; if the worker has outside opportunities and the liquidation value is small, then the credit contract must be state-dependent. However, if the worker is unable to precommit not to renegotiate with the firm, then the credit contract must be state-independent to ensure renegotiation-proofness and protect the interests of the creditor. This leads to credit rationing and under-investment.
The effect of solvent dielectric properties on the collection of oriented electrospun fibers

A simple approach to electrospinning has been developed that enables the collection of polymer, ceramic, and multiphase composite fibers, in quantity, with a high degree of spatial orientation. It has been demonstrated that a careful choice of solvent effectively eliminates the onset of the characteristic “bending” instability that is commonly associated with the electrospinning process. This allows collection of spatially oriented submicron electrospun fibers on a rotating drum without the need for elaborate mechanical or electrostatic manipulation of the electrospinning jet and/or collection target (Deitzel, J. M.; Kleinmeyer, J. D. et al. Polymer 2001, 42, 8163, Zussman, E.; Theron, A.; et al. Appl Phys Lett 2003, 82, 973, and Li, D. Wang, Y. L.; et al. Nano Lett 2003, 3, 1167). Fibers have been electrospun from a series of model polyethylene oxide/CHCl3 solutions with a range of conductivities. The experimental data confirms theoretical predictions that the onset of the bending instability is a function of the available “free” charge in the solution, which in turn is strongly influenced by the dielectric constant of the solvent. The results show that fiber orientation becomes random as the conductivity increases, indicating the need for the surface charge density to exceed a critical threshold in order for the bending instability to initiate. This method has been experimentally demonstrated with other low-dielectric constant solvents and other common polymer, ceramic, and composite materials. Furthermore, it has been demonstrated that fibers electrospun from these solutions can be mechanically drawn to submicron dimensions (∼ 200–500 nm) by controlling drum speed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Learning to predict gender from iris images

This paper employs machine learning techniques to develop models that predict gender based on the iris texture features. While there is a large body of research that explores biometrics as a means of verifying identity, there has been very little work done to determine if biometric measures can be used to determine specific human attributes. If it is possible to discover such attributes, they would be useful in situations where a biometric system fails to identify an individual that has not been enrolled, yet still needs to be identified. The iris was selected as the biometric to analyze for two major reasons: (1) quality methods have already been developed to segment and encode an iris image, (2) current iris encoding methods are conducive to selecting and extracting attributes from an iris texture and creating a meaningful feature vector.
Evolving, aging, and making culture

In a recent polemic, Leda Cosmides and John Tooby offer new proposals to bridge the gulf between biological and cultural explanations of human behaviour. By focussing on the evolved architecture of the human mind, they seek specific psychological mechanisms by which genes may influence human social institutions. A major challenge for this approach is how to trace precisely which psychological endowments, formed by the Pleistocene age, have shaped which aspect of our contemporary cultures. Here it is suggested that the temporal framework of individual human lives may provide one means of establishing clearer connections between brain structure and social institutions. For biologists this will involve extending conventional views of human ontogeny to include the phases of aging and death, which have been so important for the genesis of culture. This image of the lifespan may in turn help anthropologists come to terms with the physical bases of intergenerational transfers on which the perpetuation of culture...