cssi/SciSciGPT-SciSciNet huggingface dataset:
Contemporary applications and limitations of magnetic resonance imaging contrast materials.

Purpose: Improvements in imaging technologies have dramatically increased the ability to accurately diagnose and treat many urological disease processes. As urological patients often have chronic kidney disease, the well characterized nephrotoxicity of contrast induced nephropathy when using iodine based contrast materials has long been a concern. With the development of gadolinium based contrast agents it seemed that the concern regarding nephrotoxicity had been resolved. In 1997 a new disorder, nephrogenic systemic fibrosis, appeared in patients with severe renal failure. Nephrogenic systemic fibrosis is a serious and potentially devastating disorder characterized by progressive thickening and hardening of the skin and other body tissues, and complicated by flexion contractures of the joints.Materials and Methods: We performed a survey of the available literature on nephrogenic systemic fibrosis and magnetic resonance contrast media. We focused on mechanisms in the development of nephrogenic systemic fi...
Monolayers of Human Plasma Fibronectin at the Air/Water Interface

Human plasma fibronectin forms spread monolayers at the air/solution interface. The properties of these monolayers have been examined as a function of the composition, pH, and temperature of the aqueous phase by using low-pressure surface manometry and surface potentials. From the isotherms the molecular weight of HPFN was determined
Kidney cancer in 2012: New frontiers in kidney cancer research

2012 has been an exciting year for kidney cancer research. From the FDA approval of a new targeted agent to revival of interest in immunotherapy, several interesting studies were published that generated considerable interest.
Effects of initial anisotropy on the finite strain deformation behavior of glassy polymers

A polymeric product generally possesses a residual state of orientation incurred due to processing. The pre-oriented polymer exhibits a highly anisotropic mechanical behavior as characterised by a yield stress and post yield deformation which are both direction dependent. In this paper, polycarbonate (PC) has been subjected to various magnitudes of pre-orientation via uniaxial compression. The subsequent anisotropic yield and post yield behavior is then experimentally determined, also by compression. A constitutive model of glassy polymer deformation proposed by two of the authors is found to be successfully predictive of the prominent features of the observed experimental behavior.
Internet-based display of remotely-acquired ambient radiation data

The World-Wide Web is a powerful medium for disseminating radiation information in a readily and universally retrievable manner. Ambient monitoring of radiation measurements at a New York City location (Jacobi Hospital, Bronx, NY 10461), with automated publication of the data on the Web, has been ongoing since 1998. Several times daily, specialized communications software automatically retrieves the data by modem to a central base computer from where it is uploaded to an Internet-accessible Web page. The data are then accessible by standard Internet Web browser at the address www.aw-el.com/nyc/. This automated acquisition and display system has run with uninterrupted operation and minimal operator intervention for over 3 years. As the Internet becomes a ubiquitous conduit for information transmittal, the Web can serve as an effective means of display for radiation data, with relevance to many health physics applications discussed herein.
Multimodal displays to enhance human robot interaction on-the-move

The U.S. Army is exploring the use of advanced technologies such as tactile and spatial (3-D) audio displays to enhance Soldier performance in human-robot interaction (HRI) tasks. A field study was conducted at the U.S. Army Research Laboratory (ARL) in 2006 to determine the extent to which the integration of spatial auditory and tactile displays affects soldier situation awareness in a simulated UV HRI target search task performed in a moving HMMWV. Participants were 12 civilian males ranging in age from 18 to 46 years, with a mean age of 32 years. Participants performed a target search task, in which they searched for one target symbol among 50 non-target symbols displayed on an 18-inch diagonal computer monitor (a 30° field of view (FOV) visual display). Participants received audio and tactile cues to indicate on which third of a computer screen the target symbol was located. The independent variables were display modality, signal azimuth, participant age, and HMMWV movement condition. Display modalities were visual displays with supplemental cues in three display modalities; spatial audio, tactile, and combined spatial audio + tactile. The dependent variables were participant response time and accuracy, as well as the participant's subjective workload rating of display modality effectiveness. Accuracy data indicated that participants located over 99% of the targets correctly. Display modality was significant in terms of participant workload ratings, but was not significant for response time. Response time data indicated that no one display modality provided the shortest response time to all age groups, for all terrains. Workload with auditory + tactile displays was rated lowest of the three display modalities, which may have been because the combination audio + tactile display incorporated cues from both the audio and tactile modalities, an advantage in an environment with strong auditory and tactile distractors. The discrepancy between the workload and the performance data indicate that a greater understanding is needed of the role of each modality in on-the-move operations. Future research will deal with multimodal directional cues that can inform Soldiers of important HRI events 360° around of their field of view.
Oil Spill Clean Up Project

On April 20, 2010, the Deepwater Horizon oilrig sank in the Gulf of Mexico, resulting in an oil spill of 4.9 million barrels, one of the largest environmental disasters in United States history. In response to this disaster, the X Prize Foundation sponsored the Wendy Schmidt Oil Cleanup X Challenge, with a one million dollar top prize for engineers to develop better ways to clean up oil after an offshore oil spill. Inspired by the oil spill cleanup challenge, a class project was developed for students in a junior-level fluid mechanics course to develop and implement an oil-spill cleanup solution. Students had one semester to design and build an oil spill cleanup device. At the end of the semester final testing took place in a 20-foot long water table, which was filled with water 6 inches deep. Then for each team of 3–4 students 100 mL of cooking oil was dispersed into the water table, and they had 20 minutes to recover as much of the oil as they could. The grading for the project was based in part on the percentage of the oil the students could recover in the allotted time. The students employed a wide range of techniques, including skimmers, scoopers, and absorbers. The students also had to write a report explaining how their model solution in the water table could be scaled up to full-scale use in an actual offshore oil spill.Copyright © 2011 by ASME
An overview of reference materials prepared for standardization of DNA typing procedures

Although DNA typing is an accurate, precise, and robust procedure, quality assurance is enhanced by availability of a suitable reference material. The National Institute of Standards and Technology (NIST) recently released a Standard Reference Material (SRM) that meets the calibration and quality assurance needs of laboratories that perform DNA typing. Each step of the analytical process of DNA typing may be verified by one or more of twenty different components of the SRM. As newer, more sensitive methods for DNA typing have been introduced into the human identification laboratory repertoire, new SRMs will be required for quality assurance. A second SRM for PCR-based tests is under development and soon to be available, is also described.
Dual Core Optical Fiber for Distributed Brillouin Fiber Sensors

A dual core optical fiber is designed and fabricated for simultaneous measurements of strain and temperature in distributed Brillouin sensors. Brillouin frequency shift difference of 120 MHz between the two cores is demonstrated.
Maxillary distraction osteogenesis

Rigid external distraction is a very powerful technique for reconstruction of patients with both congenital and acquired severe caraniomaxillofacial disorders. Patients with extensive bone loss or dysgenesis in the facial skeleton traditionally challenged our standard reconstructive procedures. Distraction osteogenesis through rigid external distraction now allows positioning of displaced and hypoplastic skeletal components in a gradual rhythmic process with spontaneous orthotopic deposition of bone, taking advantage of the natural healing processes of the patients themselves. In this report we discuss some common applications of rigid external distraction of the midfacial skeleton, including indications for treatment, surgical technique, and postoperative results.
The virology–RNA biology connection

My goal in writing this article is to offer my personal reflections on RNA research, focusing on the last 20 years, to be published in a special issue marking the 20th anniversary of RNA, the premier journal in the then-emerging but now well established field of RNA biology. While I have published a number of papers relevant to RNA research, my main focus has always been on virology and I will therefore take this opportunity to remind especially younger readers that RNA research actually initially grew out of virology and that these two subjects continue to be highly interconnected.
Magnetic Fields Due to Resonance Absorption of Laser Light

We discuss the generation of dc magnetic fields due to the resonant excitation of plasma waves by an obliquely incident, plane-polarized laser beam. We show that the averaged forces on the electrons due to the plasma waves produce magnetic fields perpendicular to the plane of incidence. Megagauss field levels may be reached. Computer simulations verify our theoretical predictions.
Targeting Bcl-2 in CLL: cui bono?

Antagonizing function of Bcl-2 is an attractive goal in chronic lymphocytic leukemia (CLL) and other lymphoid malignancies. In this issue of Blood , Al-harbi et al describe a way to combine mRNA expression data from several Bcl-2 family members into a tool that predicts in vitro sensitivity of CLL
Impact of Primary User Emulation Attacks on Dynamic Spectrum Access Networks

Primary user emulation attack (PUEA) is a denial of service (DoS) attack unique to dynamic spectrum access (DSA) networks. While there have been studies in the literature to detect and mitigate PUEA, the impact of PUEA on the performance of secondary networks has seldom been studied. In this paper, we analyze how PUEA affects call dropping and delay in secondary networks carrying both real-time traffic and non-real-time traffic. Numerical results indicate that PUEA can increase the number of dropped calls by up to two orders of magnitude and can increase the mean delay by up to a factor larger than two. We then evaluate the performance of secondary networks that deploy the protocols which we proposed previously to mitigate PUEA. Our protocols reduce the number of dropped calls by up to one order of magnitude. Our protocols are also shown to exhibit almost the same delay performance as that of a system with no PUEA, for low malicious traffic load. When malicious traffic load is high, our protocols provide an improvement on the delay performance by up to 54%.
Numerical analysis of relationship between blocking and driving capability in 6H-SiC UMOSFET

Abstract Devices made of 6H-SiC have gained much attention owing to their superior characteristics. In this paper, we use an advanced device simulator, ADEPT, with the robust design of an experimental approach to analyze the trade-off between the blocking and driving capability in the designed 6H-SiC UMOSFET. New models based on the experimental data were created for the impact ionization and carrier mobility. Three device parameters, channel length, channel region doping and drift region doping, were selected to check their effects on the device's behavior. Based on our analysis, the channel length of the UMOSFET is the most significant factor among the chosen parameters in deciding the capability of the designed device. Special concern has to be directed to the device design to compromise the unavoidable performance trade-off.
Quartz resonator based gas mass spectrometry

A mass spectrometry gas sensing method using tuning fork crystal quartz resonator was investigated. Resonant frequencies and quality factors of 32.768kHz and 40.000kHz resonators were measured in nine different gases (H 2 , He, C 2 H 2 , 4%H 2 + 96%N 2 , N 2 , Air, O 2 , Ar and SF 6 ) at 296K and 1 atm. Resonant frequencies ƒ 0 and quality factors Q of the resonators decreased as a function of molecular mass of the gas as expected from gas theory. The linear relationship between ƒ 0 and molecular mass can be utilized as a gas sensing method, with sensitivity of 0.236Hz/g/mol. General gas sensing designs have been put forward using gas filtering membranes, Knudsen compressor and MEMS quartz resonators.
Nonbinary LDPC-Coded Mode-Multiplexed Coherent Optical OFDM 1.28-Tbit/s 16-QAM Signal Transmission Over 2000 km of Few-Mode Fibers With Mode-Dependent Loss

We demonstrate the possibility of nonbinary LDPC-coded mode-multiplexed coherent optical OFDM 1.28-Tbit/s 16-QAM signal transmission over 2000 km of few-mode fiber (FMF) with mode-dependent loss (MDL) by using an advanced mode-coupling compensation scheme. The performance of proposed coded-modulation scheme is evaluated for different number of spatial modes. The simulation results indicate that the MDL is the predominant effect in the long-haul optical transmission based on FMFs. Different pilot-aided OFDM based compensation methods are studied, and it has been found that minimum mean-square estimation with linear interpolation method is the most robust against mode coupling and MDL. We also show that the nonbinary LDPC-coded modulation provides about 1 dB improvement over binary LDPC-coded modulation (16 QAM OFDM and MDL of 25 dB). Finally, we study the degradation of increasing the number of modes and investigate the proposed scheme for different MDL values in both fourand eight-mode fibers.
Upregulation of Adenosine A1 Receptors Facilitates Sinoatrial Node Dysfunction in Chronic Canine Heart Failure by Exacerbating Nodal Conduction Abnormalities Revealed by Novel Dual-Sided Intramural Optical Mapping

Background—Although sinoatrial node (SAN) dysfunction is a hallmark of human heart failure (HF), the underlying mechanisms remain poorly understood. We aimed to examine the role of adenosine in SAN dysfunction and tachy-brady arrhythmias in chronic HF. Methods and Results—We applied multiple approaches to characterize SAN structure, SAN function, and adenosine A1 receptor expression in control (n=17) and 4-month tachypacing-induced chronic HF (n=18) dogs. Novel intramural optical mapping of coronary-perfused right atrial preparations revealed that adenosine (10 μmol/L) markedly prolonged postpacing SAN conduction time in HF by 206±99 milliseconds (versus 66±21 milliseconds in controls; P=0.02). Adenosine induced SAN intranodal conduction block or microreentry in 6 of 8 dogs with HF versus 0 of 7 controls (P=0.007). Adenosine-induced SAN conduction abnormalities and automaticity depression caused postpacing atrial pauses in HF versus control dogs (17.1±28.9 versus 1.5±1.3 seconds; P<0.001). Furthermore, 10...
Electrical resistance of single-wall carbon nanotubes with determined chiral indices

The properties of a carbon nanotube (CNT), in particular a single-wall carbon nanotube (SWNT), are highly sensitive to the atomic structure of the nanotube described by its chirality (chiral indices). We have grown isolated SWNTs on a silicon substrate using chemical vapor deposition (CVD) and patterned sub-micron probes using electron beam lithography. The SWNT was exposed by etching the underlying substrate for transmission electron microscope (TEM) imaging and diffraction studies. For each individual SWNT, its electrical resistance was measured by the four-probe method at room temperature and the chiral indices of the same SWNT were determined by nano-beam electron diffraction. The contact resistances were reduced by annealing to typically 3-5 kΩ. We have measured the I-V curve and determined the chiral indices of each nanotube individually from four SWNTs selected randomly – two are metallic and two are semiconducting. We will present the electrical resistances in correlation with the carbon nanotube diameter as well as the band gap calculated from the determined chiral indices for the semiconducting carbon nanotubes. These experimental results are also discussed in connection with theoretical estimations.
SEXUAL PREFERENCES OF FEMALE BROWN-HEADED COWBIRDS (MOLOTHRUS ATER) FOR PERCHED SONG REPERTOIRES

Abstract The importance of repertoire size to mate choice by female songbirds has been widely debated but has not been addressed in Brown-headed Cowbirds (Molothrus ater; hereafter ”cowbirds”), despite extensive work on this species' songs. Male cowbirds cycle through repertoires of 2–8 perched song (PS) types in rapid sequences immediately prior to and during copulation, which suggests that repertoire size or content is important in mating contexts. Because male mating success in one well-studied cowbird population is correlated with large PS repertoires, we predicted that repertoire size is a cue in female mate choice. To test that prediction, we played three repetitions of conspecific songs in rapid succession to estradiol-primed female cowbirds (M. a. obscurus), to simulate the rapid song sequences that accompany naturally occurring matings. Females were presented with three different PS types, three repetitions of the same type, and heterospecific control songs of the same duration as the conspecific...
Aerosol spectral optical depths: Jet fuel and forest fire smokes

The Ames autotracking airborne sun photometer was used to investigate the spectral depth between 380 and 1020 nm of smokes from a jet fuel pool fire and a forest fire in May and August 1988, respectively. Results show that the forest fire smoke exhibited a stronger wavelength dependence of optical depths than did the jet fuel fire smoke at optical depths less than unity. At optical depths greater than or equal to 1, both smokes showed neutral wavelength dependence, similar to that of an optically thin stratus deck. These results verify findings of earlier investigations and have implications both on the climatic impact of large-scale smokes and on the wavelength-dependent transmission of electromagnetic signals.
Mutant chinese hamster cells with a thermosensitive hypoxanthine-guanine phosphoribosyltransferase.

Abstract By selecting variants of Chinese hamster cells that were resistant to 6-thioguanine at 39°C, but which would continue to grow in HAT medium at 33°C, we have isolated cell lines with thermosensitive phenotypes. These clones form colonies in HAT medium and incorporate 14 C-hypoxanthine much more efficiently at 33°C than at 39°C. The specific activity of hypoxanthine-guanine phosphoribosyltransferase is at least 10 times higher in variant cells grown at 33°C than in those grown at 39°C, and the enzymes from the variant clones are inactivated in vitro at 39°C 7–9 times more rapidly than is the enzyme from wild-type cells. The results are consistent with the conclusion that the selected clones have missense mutations in the structural gene for the enzyme.
The Performance of Growth Stocks and Value Stocks in the Pacific Basin

Many studies show that value stock strategies outperform growth stock strategies in U.S. markets and in international markets. However, the evidence is not clear as growth stocks have had higher returns in a few countries. Because the behavior of stock markets vary between different geographic regions, it is possible that the performance of these strategies may differ in the Pacific Rim region. We examine the performance of value stocks and growth stocks, defined on the basis of market price to book value per share, over the 10-year period 1986-1996, for six Pacific Rim countries. Based on over 11,900 annual stock returns, value stocks generally outperformed growth stocks over the 10-year period, and in the various Pacific Rim country stock markets. In addition, smaller cap stocks outperformed large cap stocks. Regardless of cap size, however, value stocks, on the whole, outperformed growth stocks. When growth stocks occasionally outperformed value stocks, the margin of difference tended to be small.
Infections due to Lancefield group C streptococci.

The group G streptococcus has surfaced in the past 10 to 15 years as an important opportunistic and nosocomial pathogen. Although more precise organism recognition accounts for a portion of these cases, there can be little doubt that the group G streptococcus has become a more prevalent pathogen. Commercial kits, utilizing staphylococcal coagglutination or latex agglutination, are now available, affording all clinical laboratories the opportunity to identify this organism easily. Published reviews encompassing the experiences of a single institution or even several institutions affiliated with a single medical center, particularly as they were influenced by referral patterns, did not reflect the broad scope of infections that we discovered by extending our survey into the community, beyond the medical center complex and its immediate affiliated hospitals. Although malignancy is the single most obvious background factor, alcoholism and diabetes are also important host determinants of infection. Skin and soft-tissue infections (and surface sources of infection) are equally important among patients with or without the element of malignancy. Polymicrobial infection, including polymicrobial bacteremia, is an important feature, with S. aureus infections accounting for most of these cases, relating to the skin and soft tissue sources of infections so commonly seen. We saw a panorama of problems including endocarditis, septic arthritis, pleuropulmonary infections, bone and joint infections, puerperal sepsis and neonatal infection, peritonitis and ophthalmitis; we also saw a significant number of patients with bacteremia and no apparent primary source of infection. Response to antibiotic therapy was dictated by the nature of the underlying diseases, and individuals without a background of malignant disease did well, particularly those with skin and soft-tissue infections. While the literature suggests that patients with endocarditis and septic arthritis due to this organism respond poorly to antibiotic therapy, implying that such failures relate to in vitro antibiotic phenomena, we preferred to examine the problem from the viewpoint of the host(s) involved. Subacute endocarditis and acute endocarditis due to the group G streptococcus may be clinically separable, and thus require separate therapeutic approaches. In patients with septic arthritis, prosthetic devices, prior joint disease and immunosuppressive diseases and therapy often adversely influence the response to antibiotic therapy.(ABSTRACT TRUNCATED AT 400 WORDS)
Nasal Lymphoid Tissue (NALT) as a Mucosal Immune Inductive Site

Intranasal (i.n.) immunization is a very effective route for inducing mucosal immunity, but the cellular mechanism responsible for regulating and disseminating these responses is not fully understood. The authors studied the role of nasal lymphoid tissue (NALT) as a mucosal inductive site by using highly purified NALT cells obtained by a new method of mechanical isolation. The NALT cells, like Peyer's patch (PP) cells, were smaller in size and less granular than lymphocytes from salivary glands (SG) and small intestinal lamina propria (LP). The NALT cells isolated from i.n. immunized mice contained antigen-specific antibody-secreting cells (ASC) predominantly of immunoglobulin (Ig)A isotype, similar to those also recovered from salivary glands in a time course study. However, the higher proportion of smaller sized sports formed by NALT cells in ELISPOT assays suggested that these cells were less differentiated precursors of those found in salivary glands. This was supported by the fact that after i.n. immunization, IgA ASC appeared in NALT, as well as in mucosal effector sites SG and LP, but none or very few in another mucosal inductive site, PP. In contrast, after intragastric (i.g.) immunization, IgA ASC were detected in PP, along with the SG and LP, but none or very few in NALT. Furthermore, after i.n. immunization, lymphocytes from NALT but not PP proliferated in response to the specific antigen in culture. These findings imply that NALT served as an inductive site for IgA antibody responses at mucosal effector sites.
Feminism and its ghosts: The spectre of the feminist-as-lesbian

This article contends that feminism is haunted by its past, and that to be haunted means that feminists need to bear witness to the possibilities, often unrealized, of that past and to actively res...
Serum Lipid and Fat Tolerance Studies in Normal, Obese and Atherosclerotic Subjects

Fat tolerance tests demonstrated elevated and prolonged postprandial lipemia in markedly obese, hypercholesteremic, and atherosclerotic subjects when compared with normal individuals. An improvement of this abnormal fat tolerance was achieved following rigid fat restriction in hypercholesteremic and atherosclerotic subjects and following weight reduction in the extremely obese. An inferential relationship is suggested between extreme obesity and atherosclerosis.
A Scalable Architecture for RSA Cryptography on Large FPGAs

The RSA algorithm is the standard for public-key cryptography today, with Montgomery multiplication the most common mechanism of implementation due to modulo operations using a bitwise shift in place of a division operation. Several Montgomery designs have been proposed for ASIC and FPGA implementation based on limited resource availability to satisfy the computational burden. FPGAs are now available that have large configurable logic resources in addition to dedicated high-speed ALU logic for operations such as multiplication. This paper describes an improvement to a limited resource Montgomery multiplier design, the MWR2MM algorithm proposed by Tenca and Koc, which is suitable for implementation on large FPGAs. The design can be scaled to utilize available FPGA multipliers, CLB logic and frequencies of operation. Implementation and design choices are discussed for an RSA core based on this design, and a comparison against the OpenSSL open source cryptographic library is given. Our results show a 1024-bit RSA core on a 100MHz Virtex2 Pro 100 FPGA platform to be 3.13x faster than an equivalent software implementation on a 2.8 GHz Intel Xeon PC workstation.
Modified Soy Proteins with Improved Foaming and Water Hydration Properties

Soy proteins were modified by alkali treatment at pH 10.0, followed by papain hydrolysis. Solubility, water hydration capacity (WHC), surface hydrophobicity, foaming and emulsifying properties of unmodified, alkali-treated, and papain-modified soy protein (PMSP) were compared. PMSP exhibited higher solubility (100% at pH > 7.0), WHC (3.13) and hydrophobicity (40.8) than unmodified soy protein which had solubility 68.5%, WHC 0.21, and hydrophobicity 8.1. The PMSP had foaming capacity (22.0 mL) similar to egg white (21.2 mL) at pH 7.0; and enhanced foam stability (36.4) compared to the unmodified control (32.9). In general, alkali-treated soy had lower functional properties. Emulsifying properties of PMSP and alkali treated soy were unchanged by the modification. PMSP could be used as an egg white substitute in foaming applications at neutral pH.
Reader attitudes toward journal-based continuing education for EMS personnel.

Abstract : Recertification requirements and new curricula place increased importance on continuing education (CE) for emergency medical services (EMS) personnel. To be effective, continuing education not only must be accessible to EMS personnel, but it must be also acceptable. Journal-based continuing education was selected to improve accessibility, but questions were raised about its acceptance. Although there were some significant differences found between the feelings of basic and advanced EMS personnel, a study conducted on six articles showed that participants overall liked this method. The study also found that some articles significantly generated more reader response than others.
In situ long-term reductive bioimmobilization of Cr(VI) in groundwater using hydrogen release compound

The results of a field experiment designed to test the effectiveness of a novel approach for long-term, in situ bioimmobilization of toxic and soluble Cr(VI) in groundwater using a hydrogen release compound (HRC)--a slow release glycerol polylactate--are described. The field experiment was conducted at the Hanford Site (Washington), a U.S. Department of Energy nuclear production facility, using a combination of hydrogeological, geophysical, geochemical, and microbiological measurements and analyses of water samples and sediments. The results of this experiment show that a single HRC injection into groundwater stimulates an increase in biomass, a depletion of terminal electron acceptors O2, NO3-, and SO4(2-), and an increase in Fe2+, resulting in a significant decrease in soluble Cr(VI). The Cr(VI) concentration has remained below the background concentration in the downgradient pumping/ monitoring well, and below the detection limit in the injection well for more than 3 years after the HRC injection. The degree of sustainability of Cr(VI) reductive bioimmobilization under different redox conditions at this and other contaminated sites is currently under study.
The role of interest groups in agricultural policy design: Chile 1960–1988

This article recognizes the importance of two policy instruments in shaping the path of agriculture during its development process. The implications of agricultural price policies on the funding of agricultural research are explicitly considered in a set of structural equations for a unique path of Chilean political history. A political economy model includes four blocks of simultaneous equations estimated as an interdependent system. The level of price policies and public research investments result from the collective action exerted on the government by pressure groups of producers, consumers and taxpayers involved in the production, consumption and funding of agriculture. Copyright © 1999 John Wiley & Sons, Ltd.
Learnable And Non-learnable Visual Concepts

Valiant’s theory of the learnable is applied to visual concepts in digital pictures. Several visual concepts that are easily perceived by humans are shown to be learnable from examples by a simple algorithm. These include inaccurate copies of a picture, multiple objects, and lines in a fixed slope. However, there are simple characterizations of visual concepts which are apparently non-learnable from examples. It is shown that templates for template matching cannot be learned from a feasible number of positive examples.
A Critical Review of Correlations for Convective Vaporization in Tubes and Tube Banks

Abstract Three types of phenomenological models are used for calculating heat transfer coefficients in convective vaporization—the superposition, asymptotic, and enhancement models. These models were originally proposed for in-tube vaporization. The objective of the present study is to critically assess these models, and to establish a rational basis for a modified model. Saturated convective vaporization is of key interest in this review. Much more work has been done on in-tube flow than for tube banks. This article surveys the currently available models, and establishes the commonality and differences of the correlations. Separate emphasis is given for tube bank correlations. The correlations for tube banks are compared to those used for in-tube flow. We show that the current correlations may be grouped into three basic types—superposition, enhancement, and asymptotic models. Each type is discussed in order to address the concepts involved in them. Problems associated with certain published models are d...
On optimal frame expansions for multiple description quantization

We study the problem of finding the optimal overcomplete (frame) expansion and bit allocation for multiple description quantisation of a Gaussian signal at high rates over a lossy channel.
Posterolateral rotatory elbow subluxation with intra-articular entrapment of the radial nerve. A case report.

Posterolateral rotatory elbow subluxation with associated intra-articular entrapment of the radial nerve is extremely uncommon. To our knowledge, only one previous report has described a similar clinical entity1. We describe the case of a patient who presented to us, four weeks after injury, with severe limitation of elbow motion, pain, and motor and sensory radial nerve palsy. Definitive treatment required surgical exploration and removal of the radial nerve from the radiocapitellar joint, which facilitated reduction of the radial head. The patient was informed that data concerning the case would be submitted for publication. A thirty-seven-year-old right-hand-dominant woman presented to our clinic with a four-week history of pain in the left elbow, loss of sensation over the dorsum of the thumb and index finger, and an inability to extend the wrist and fingers. Four weeks previously, the patient had fallen onto the outstretched arm while walking outdoors. She felt immediate pain in the left elbow and went to a local emergency room, where she was found to have altered sensation in the radial-nerve distribution in the hand as well as an inability to extend the wrist and fingers. Standard radiographs of the elbow demonstrated posterolateral rotatory elbow subluxation (Figs. 1-A and 1-B), and a manipulative reduction was performed. The limb was placed in an above-the-elbow splint, and the patient was instructed to seek orthopaedic consultation. Figs. 1-A and 1-B Anteroposterior (Fig. 1-A) and lateral (Fig. 1-B) radiographs of the elbow of a thirty-seven-year-old woman who had fallen onto the outstretched arm. There is widening of the radiocapitellar joint and posterior subluxation of the radial head. The patient did not seek follow-up evaluation as instructed. Three weeks after the injury, the patient presented to our emergency room because the pain, numbness, and weakness had not resolved. Standard anteroposterior and lateral radiographs of the left …
“Magnetic Exchange Interactions in Fe/TbFe Bilayers”

We report on magnetic exchange coupling phenomena between Fe and TbFe thin films. The structures are grown utilizing D.C. magnetron sputtering from separate Tb and Fe targets and their magnetic characteristics are measured utilizing VSM and Longitudinal Kerr Rotation. In addition, Auger depth profiling and x-ray diffraction studies were conducted to study film composition and structure. Uniaxial alignment of the Fe moment in the plane of the substrate is revealed by the longitudinal Kerr measurements. The coercivity of the Fe layer varies from 19 Oe to 130 Oe depending on the azimuthal angle between the normal to the plane of the bilayer and the direction of the external field. The hysterisis loops vary in shape from rectangular in the alignment direction to S-shape in the direction orthogonal to this direction. These effects are discussed in terms of magnetic exchange coupling interactions between the ferromagnetic layer and the ferrimagnetic alloy.
The binding of a transcription factor to deletion mutants of a 5S ribosomal RNA gene

Abstract A transcription factor binds specifically to a region within the 5S ribosomal RNA gene that is known to be required for accurate initiation of transcription of the gene. We have confirmed the significance of this interaction by comparing various deletion mutants for their ability to initiate transcription and to bind the protein. Loss of specific binding of the protein occurs when the gene is deleted beyond +83 from the 3′ direction. This coincides exactly with the loss of ability to initiate transcription. In contrast, deletions entering the gene from the 5′ direction and extending beyond the 5′ border of the control region (+50/+55) give partial protection of the remainder of the control region. This observation can explain why deletions beyond the 5′ border of the control region that are unable to initiate transcription can still compete for the transcription of the wild-type 5S RNA gene.
Contributions to the Impact of the Javits Act by the National Research Center on the Gifted and the Talented

One component of the Javits Gifted and Talented Students Education Act was provision for research on a national scale. In response, The National Research Center on the Gifted and Talented (NRC/GT) was created to design and implement a research portfolio. Based on emphasis in the Javits Act on underrepresented populations, on issues of identification and programming, and on priorities of an initial NRC/GT needs assessment, we elected to concentrate on summarizing the NRC/GT research reflecting identification practices, the status of current curricular and instructional strategies and practices, the development of challenging curricula, and the effectiveness of various professional development strategies as potential catalysts for change. The history underlying the development of the Javits Act and the organization and operation of the NRC/GT are described in the article titled “Laying the Base for the Future: One Cornerstone of the Javits Act” in this special issue of the Journal of Advanced Academics (JOAA).
An Ethnic/Racial Comparison of Causal Beliefs and Treatment Preferences for the Symptoms of Depression Among Patients with Diabetes:

PurposeThe purpose of the study was to explore African American, Latino, and Non-Hispanic White adult patients with type 2 diabetes cultural perceptions of symptoms of depression and factors that predict depression care treatment preferences between these groups.MethodsA community sample of African Americans, Latinos, and White diabetic adults receiving services in 1 of 2 central Austin, Texas facilities participated in the study. Each participant was given a survey, which consisted of the following 5 components: (1) illness screener questions, (2) demographic questions, (3) Patient Health Questionnaire, (4) Depression Treatment Questionnaire, and (5) Illness Perception Questionnaire. A binary logistic regression was used to examine the relationship between cultural perceptions of symptoms and the predictor variables. A multinomial logistic regression analyses was used to examine the relationship between treatment and provider preferences for the symptoms of depression and ethnicity.ResultsThe first resea...
Pvault: a client server system providing mobile access to personal data

In this paper we describe the design for the Pvault software, which is a personal data manager that stores and retrieves data from a remote untrusted data server securely. The major advantage of Pvault is that it allows users to access their personal data from any trusted remote computer. We will describe the issues and solutions for maintaining data confidentiality and integrity when the data is stored at the remote sever, since the server itself is untrusted. Pvault also prevents Phishing and Pharming attacks and we will describe the solutions for the same.
Lightweight sensing and communication protocols for target enumeration and aggregation

The development of lightweight sensing andcommunication protocols is a key requirement for designing resource constrained sensor networks. This paper introduces a set of efficient protocols and algorithms, DAM, EBAM, and EMLAM, for constructing and maintaining sensor aggregates that collectively monitor target activity in the environment. A sensor aggregate comprises those nodes in a network that satisfy a grouping predicate for a collaborative processing task. The parameters of the predicate depend on the task and its resource requirements. Since the foremost purpose of a sensor network is to selectively gather information about the environment, the formation of appropriate sensor aggregates is crucial for optimally allocating resources to sensing and communication tasks.This paper makes minimal assumptions about node onboard processing and communication capabilities so as to allow possible implementations on resource-constrained hardware. Factors affecting protocol performance are discussed. The paper presents simulation results showing how the protocol performance varies as key network and task parameters are varied. It also provides probabilistic analyses of network behavior consistent with the simulation results. The protocols have been experimentally validated on a sensor network testbed comprising 25 Berkeley MICA sensor motes.
Chemical Vapor Deposition of Electronic Materials

Chemical vapor deposition (CVD), as the name implies, involves the formation of a deposit on a substrate caused by the reaction of chemicals transported to the substrate in the vapor phase. It is a very old technique which dates at least as far back as the chemical transport studies of Bunsen (1) and Sainte-Claire Deville (2) in the mid-nineteenth century, and which achieved commercial significance as long ago as 1880 when it was used for coating filaments in the incandescent lamp industry (3). Over the course of approximately 100 years it has developed into a very important method for material synthesis and today has application to a broad spectrum of compounds ranging from relatively easily prepared amorphous and polycrystalline deposits used as protective coatings to highly sophisticated epitaxial single crystalline films used in semiconductor devices. The growing importance of CVD is derived from the inherent versatility of this synthesis method which permits the preparation of virtually any material in essentially any geometry. In addition, CVD has a number of unique advantages, in comparison with most synthesis techniques, which include the ability to synthesize materials at relatively low temperatures and to directly synthesize compounds represented by any region of a phase diagram. This latter ability is very important for the preparation of compounds having incongruent melting points and for the synthesis of solid solutions or alloys. The ability to prepare materials at low temperatures is beneficial for achieving high purity since contamination resulting from diffusion processes and unwanted reactions can be minimized. Also, homogeneity and stoichiometry can be more easily controlled in compounds which have high equilibrium dissociation pressures near their melting temperatures, and the integrity of substrate materials can be more easily assured. An additional advantage of CVD is that it readily accommodates the
Topographic organization of the olivocochlear projections from the lateral and medial zones of the superior olivary complex

By anterograde tracing using autoradiography, we have found topographic organizations in the projections of both medial and lateral olivocochlear (OC) systems in the cat. Lateral-zone injections show an ipsilateral cochleotopic projection pattern with more medial injections projecting more basally in the cochlea. In the contralateral cochlea, in contrast, the projections from all of the lateral-zone injections were predominantly to the apex. However, detailed analysis suggests the possibility that the contralateral lateral-zone projections may have the same cochleotopic organization as the ipsilateral projections but with a heavy bias toward the apex. Medial-zone injections show a pattern in which more dorsal regions project more basally in both cochleas. The ipsilateral projections of lateral OC neurons appear to connect regions with similar best frequencies but the projections of medial OC neurons do not. Summation of data from all of the injections in each zone indicates that lateral OC projections are relatively evenly distributed throughout the ipsilateral cochlea but are predominantly to the apex in the contralateral cochlea. Medial OC projections are predominantly to the middle and basal parts of the cochlea on both sides with contralateral projections somewhat more basal than ipsilateral projections.
Neutron imaging at the Oak Ridge National Laboratory: Application to biological research

The Oak Ridge National Laboratory Neutron Sciences Directorate (NScD) has recently installed a neutron imaging beamline at the High Flux Isotope Reactor (HFIR) cold guide hall. The CG-1D beamline supports a broad range of user research spanning from engineering to material research, energy storage, additive manufacturing, vehicle technologies, archaeology, biology, and plant physiology. The beamline performance (spatial resolution, field of view, etc.) and its utilization for biological research are presented. The NScD is also considering a proposal to build the VENUS imaging beamline (beam port 10) at the Spallation Neutron Source (SNS). Unlike CG-1D which provides cold neutrons, VENUS will offer a broad range of neutron wavelengths, from epithermal to cold, and enhanced contrast mechanisms. This new capability will also enable the imaging of thicker biological samples than is currently available at CG-1D. A brief overview of the VENUS capability for biological research is discussed.
Axon Guidance Molecules and Neural Circuit Remodeling After Spinal Cord Injury

…once the development was ended, the founts of growth and regeneration of the axons and dendrites dried up irrevocably. Santiago Ramon y Cajal Cajal's neurotropic theory postulates that the complexity of the nervous system arises from the collaboration of neurotropic signals from neuronal and non-neuronal cells and that once development has ended, a paucity of neurotropic signals means that the pathways of the central nervous system are "fixed, ended, immutable". While the capacity for regeneration and plasticity of the central nervous system may not be quite as paltry as Cajal proposed, regeneration is severely limited in scope as there is no spontaneous regeneration of long-distance projections in mammals and therefore limited opportunity for functional recovery following spinal cord injury. It is not a far stretch from Cajal to hypothesize that reappropriation of the neurotropic programs of development may be an appropriate strategy for reconstitution of injured circuits. It has become clear, however, that a significant number of the molecular cues governing circuit development become re-active after injury and many assume roles that paradoxically obstruct the functional re-wiring of severed neural connections. Therefore, the problem to address is how individual neural circuits respond to specific molecular cues following injury, and what strategies will be necessary for instigating functional repair or remodeling of the injured spinal cord.