cssi/SciSciGPT-SciSciNet huggingface dataset:
A NEW HIGH ENERGY APPROXIMATION OF INTRA-BEAM SCATTERING FOR FLAT ELECTRON AND POSITRON BEAMS

We derive completely integrated formulae for emittance growth rates due to intrabeam scattering for flat electron and positron beams in the high energy limit, including the effect of lattice parameters that vary around the accelerator ring. Using the accelerator lattice for the Accelerator Test Facility’s electron damping ring at KEK, we compare our results to the more complete theory as well as to other high energy approximations.
Abstract #5668: Identification of primary cilia in human breast tissue and cell lines

Primary Cilia (PC), solitary microtubule-based structures present in various types of eukaryotic cells, were recently found to be critical platforms for several signal transduction pathways. Alterations in PC-associated genes were reported to be related to certain congenital and acquired diseases. The functions of PC are cell type specific and are just beginning to be understood. Their presence and roles in the human breast are largely unknown. We sought to examine the occurrence of PC in several human breast cell lines, as well as in normal and malignant human breast tissues. Our results revealed different patterns of PC expression among human breast cell lines. By using a computer-aided quantification approach of immunofluorescence for acetylated tubulin, a marker of PC, we found a relatively high expression of PC in fibroblasts isolated from normal breast (PC present in 55% of cells) and epithelial cell lines derived from normal breast including human mammary epithelial cells (HMEC) and MCF-10A cells (in 8 -16% of cells); a much lower occurrence in MDA-MB-435 cells (in 0.7% of cells), MDA-MB-231 (in 0.2% of cells), and T-47D cells (in 0.2 % of cells); and virtually absent in other breast cancer cell lines including MDA-MB-468, SK-BR-3, ZR-75-1, BT-474 and MCF-7. We also explored the presence of PC in formalin-fixed, paraffin-embedded benign and cancerous human breast tissues by immunofluorescence. PC were readily found in benign, histological normal breast tissues, primarily in fibroblasts and mammary myoepithelial cells (identified by immunostaining for keratin 14), while rarely in luminal epithelial cells (identified by pancytokeratin staining and location). In the cancer tissues examined thus far, no primary cilia have been definitively identified in cancerous epithelial cells by immunofluorescence. These observations indicate that PC are normally present in stromal and epithelial cells of the human breast. However, their occurrence is lower in breast cancer epithelial cells, raising the possibility that loss of PC is associated with carcinogenesis. Citation Information: In: Proc Am Assoc Cancer Res; 2009 Apr 18-22; Denver, CO. Philadelphia (PA): AACR; 2009. Abstract nr 5668.
High-fidelity radiosity rendering at interactive rates

Existing radiosity rendering algorithms achieve interactivity or high fidelity, but not both. Most radiosity renderers optimize interactivity by converting to a polygonal representation and Gouraud interpolating shading samples, thus sacrificing visual fidelity. A few renderers achieve improved fidelity by performing a per-pixel irradiance “gather” operation, much as in ray-tracing. This approach does not achieve interactive frame rates on existing hardware.
Tree-structured method for improved LUT inverse halftoning

Recently we have proposed a Look Up Table (LUT) based method for inverse halftoning of images. The LUT for inverse halftoning is obtained from the histogram gathered from a few sample halftone images and corresponding original images. The method is extremely fast (no filtering is required) and the image quality achieved is comparable to the best methods known for inverse halftoning. The size of the LUT can become bigger even though most of the elements in the table are not used in practice. We propose a tree structure which will reduce the storage requirements of an LUT by avoiding nonexistent patterns. Tree-structure inverse halftoning will need only a fraction of its LUT equivalent for storage. We demonstrate the performance on error diffused images.
Laser line-scan fluorescence and multispectral imaging of coral reef environments

During the summer of 1996 a series of field trials were conducted in the Florida Keys and Bahama Islands to evaluate the ability of a unique laser line scan system to measure and map the fluorescent characteristics of coral reef environments. Typical fluorescence maps that were obtained are presented and compared with monochrome and RGB color images of the same reefs. The monochrome images were obtained with the laser line scan system simuftaneously with the fluorescent maps. The RGB images, which were also obtained with the laser line scan system, were recorded in the same location on a subsequent thai.
A micromachined Knudsen pump for on-chip vacuum

This paper describes a single-chip micromachined implementation of a Knudsen pump-a type of vacuum pump that works by the principle of thermal transpiration, has no moving parts, and consequently offers high reliability. A 6-mask process was used to fabricate the pump from a glass substrate and a silicon wafer. A single stage pump and two integrated pressure sensors occupy 1.5 mm/spl times/2 mm. Measurements show that this device can evacuate a cavity to 0.46 atm while operating at atmospheric pressure and using 80 mW input power. Temperature measurements show thermal isolation on the order of 10/sup 4/ K/W between the polysilicon heater used to operate the pump and the rest of the device.
A dipole antenna system for simultaneous transmit and receive

A design of a 3-element simultaneous transmit and receive (STAR) antenna system is presented. The transmitter is an array of two equal-phase collinear half wavelength dipoles positioned such to create 180° near-field phase difference at the receiver's location. With proper amplitude excitation, this configuration achieves isolation better than 70dB at the antenna resonant frequency and >45dB within a 13% bandwidth. The proposed antenna system maintains similar E- and H-plane patterns for both, the transmitter, and the receiver. The proposed configuration can be tuned (phase and amplitude) for better isolation at any frequency within the bandwidth while maintaining consistent and similar radiation patterns.
On whether to prosecute suspected price-fixing conspi racies: A hypothesis-testing approach

This paper analyses the antitrust policy decision of whether to sue prosecute a suspected price-fixing cartel. The analysis is conducted in the Bayesian hypothesis-testing mode, using a Cournot market. framework. This approach recognizes that the decisions to instilute an investigation, file suit, or go to trial, are all binary decisions that involve testing a null hypothesis: notably. the hypothesis that the antitrust laws have not been violated versus the alternative hypothesis that they have been violated. Rejecting the null hypothesis is equivalent to electing to proceed along the prosecution path. The paper demonstrates that formalization of the decision-making process can help to enhance our understanding of the factors that underlie the various decisions, and particularly how those factors can influence the decisions, and provides guldellnes for antllrust administration under the current U. S. antitrusl laws.
Cluster Expansion for the Ising Model

A binary alloy system with nearest‐neighbor interaction which forms a rigid lattice is the (ideal) Ising system. The present paper is an application of the theory of classical fluids, as developed by Morita and Hiroike, to such systems. The partition function for the Ising system is made formally equivalent to that for a binary fluid as discussed by Morita. Then, using the methods of graph theory, a high‐temperature expansion is obtained for fixed long‐range order parameters. By performing a partial summation, one finds that the free energy is given in terms of connected diagrams which are composed of βJ bonds, and black circles Mn. The quantities Mn are evaluated by noting that the diagrammatical expressions for these quantities appear in the expansion of the grand potential of a soluble problem.The method is illustrated in the case of an AB alloy or the ferromagnetic Ising system which form cubic lattices. Chang's result is easily obtained. The extension of this method to higher terms and its applicatio...
An abbreviated implicit spatial context learning task that yields greater learning

The spatial contextual cuing task (SCCT) (Chun & Jiang, 1998) is an implicit learning task that appears to depend on the medial temporal lobes. This unusual combination has been of interest in functional imaging studies and research with clinical populations, where testing time is at a premium. However, the original version of the SCCT is time-consuming. In this study, 29 young adults (age range, 18–22 years) completed the SCCT, in which participants respond to the orientation of a target in arrays containing 11 distractors. Either 12 (original version) or 6 (abbreviated version) arrays repeated across the experiment, with the remaining novel arrays being generated randomly. Results revealed that the magnitude of learning (faster responses to repeated versus novel arrays) was larger when there were fewer repeated arrays, with no explicit awareness in most participants. Thus, the abbreviated version remained implicit, with the additional benefit of increasing the magnitude of learning.
Solid-state fermentation of natural birch lignin by Phanerochaete chrysosporium

A strain of white rot fungus, Phanerochaete chrysosporium Burds. ME446, has been characterized with respect to the extent and rate of Betula nigrificans lignin and non-lignin conversion by solid-substrate fermentation for different culture conditions. Moisture content, inoculum density, nitrogen supplementation and autoclaving of birch solids significantly affected lignin conversion rates and yields in 20 day fermentations. Oxygen favoured lignin over non-lignin conversion at partial pressures of 1.0 atm. Oxygen pressures of 2.0 atm severely inhibited both lignin and non-lignin conversions. Carbon dioxide partial pressures of 0.25, 0.5 and 1.0 atm at oxygen pressures of 1.0 atm increasingly inhibited both lignin and non-lignin conversion rates and yields. The results of these studies demonstrate the effects of major process variables and suggest a need to control the gas environment for process optimization.
Building polyhedra by self-assembly: Theory and experiment

We investigate the utility of a mathematical framework based on discrete geometry to model biological and synthetic self-assembly. Our primary biological example is the self-assembly of icosahedral viruses; our synthetic example is surface-tension-driven self-folding polyhedra. In both instances, the process of self-assembly is modeled by decomposing the polyhedron into a set of partially formed intermediate states. The set of all intermediates is called the configuration space, pathways of assembly are modeled as paths in the configuration space, and the kinetics and yield of assembly are modeled by rate equations, Markov chains, or cost functions on the configuration space. We review an interesting interplay between biological function and mathematical structure in viruses in light of this framework. We discuss in particular: (i) tiling theory as a coarse-grained description of all-atom models; (ii) the building game—a growth model for the formation of polyhedra; and (iii) the application of these models to the self-assembly of the bacteriophage MS2. We then use a similar framework to model self-folding polyhedra. We use a discrete folding algorithm to compute a configuration space that idealizes surface-tension-driven self-folding and analyze pathways of assembly and dominant intermediates. These computations are then compared with experimental observations of a self-folding dodecahedron with side 300 µm. In both models, despite a combinatorial explosion in the size of the configuration space, a few pathways and intermediates dominate self-assembly. For self-folding polyhedra, the dominant intermediates have fewer degrees of freedom than comparable intermediates, and are thus more rigid. The concentration of assembly pathways on a few intermediates with distinguished geometric properties is biologically and physically important, and suggests deeper mathematical structure.
Stevenson received the Whipple award

David J. Stevenson received the Whipple Award at the 1994 Spring Meeting in Baltimore. The award is given for outstanding scientific contributions to the field of planetology. The citation and Stevenson's response are given here.
Effect of H2S on the Performance and Long-Term Stability of Pd/Cu Membranes

The objective of this work was to fabricate palladium membranes with a Pd/Cu alloy top layer and to investigate the performance and long-term stability of the membranes in small concentrations of H...
Designing socio-technical environments in support of meta-design and social creativity

This paper provides elements of a transformational conceptual framework for CSCL by focusing on how learning takes place when the answer is not known (this being the case for complex design problems in numerous domains encountered in lifelong learning activities). The paper postulates, explores, and discusses visions, theories, systems, practices, and methods for CSCL with a focus on reflective communities (bringing stakeholders together from many different backgrounds, requiring cultural and epistemological pluralism to make all voices heard), metadesign (allowing owners of problems to act as designers and active contributors, and not only as consumers), and social creativity (bringing different and often controversial points of view together to create a shared understanding among stakeholders that can lead to new insights, new ideas, and new artifacts). Innovative socio-technical environments are needed to make progress in achieving these objectives. Examples and characteristics of such environments will be briefly presented and discussed. Some implications and challenges for future research in CSCL are derived and articulated.
Comparative analysis of the rotavirus NS53 gene : conservation of basic and cysteine-rich regions in the protein and possible stem-loop structures in the RNA

Abstract NS53, the product of rotavirus gene 5, is an RNA-binding protein that contains a cysteine-rich region and is a component of early replication intermediates. To gain information about the structure of NS53 and its RNA, we determined the nucleotide sequence of gene 5 for the human viruses Wa (serotype 1) and DS1 (2) and the simian virus SA11 (3) (Patton strain) and compared them and their deduced amino acid sequences to those reported for the bovine viruses UK (6) and RF (6) SA11 (3) (Both strain), the human virus Rohivg803, and the group C porcine virus PRV. The results showed that gene 5 for human, simian, and bovine strains have lengths of 1564-1567, 1611, and 1579-1581 nucleotides (nt) and encode proteins of 486, 495, and 491 amino acids, respectively. Comparison of the protein sequences for NS53 among different serotypes showed that they are extremely divergent with many sharing amino acid homologies of only 36-38%. Even NS53 from viruses isolated from the same species possessed relatively poor homology, e.g., DS 1 versus Wa was 68%. The first 150 amino acids of NS53 exhibited a greater degree of conservation then the rest of the protein. Near the amino terminus, NS53 contains three basic regions and a cysteine-rich domain, suggesting that this area is responsible for the RNA-binding activity of the protein. Present in the cysteine-rich domain of all group A and C viruses was the motif C-X 2 -C-X 5 -C-X 2 -C-X 3 -H-X-C-X 2 -C-X 5 -C. Although this motif may form one or two zinc fingers, the fact that it is highly conserved indicates that it plays a critical role in the function of protein. Comparison of the nucleotide sequences for gene 5 showed that the entire 5′-noncoding region and the first 24 nt of the NS53 ORF are conserved. RNA-folding predictions suggest that this region of the NS53 mRNA can interact with itself, producing a stem-loop structure similar to that found near the 5′-terminus of the NS35 mRNA. Thus, such structures may be common to all rotavirus mRNAs, perhaps functioning as signals for packaging of RNAs into replication intermediates or regulating mRNA translation.
Structure-function relationship of human parathyroid hormone in the regulation of vitamin D receptor expression in osteoblast-like cells (ROS 17/2.8).

Studies of the relationship between PTH structure and function in the activation of protein kinases have revealed that different regions within the biologically active PTH-(1-34) peptide are responsible for different functions. The first two N-terminal amino acids are required for plasma membrane adenylyl cyclase stimulation, and the C-terminal region 29-32 is necessary for the translocating activity of protein kinase C. In the present study, we explored the structure-function relationship of human (h) PTH in the regulation of the vitamin D receptor (VDR) in osteoblast-like cells (ROS 17/2.8). VDR-rich cytosol extract was prepared after the confluent cells were incubated with different hPTH fragments for 16 h. hPTH-(1-34) at concentrations of 10(-9)-10(-7) M caused a dose-dependent decrease in VDR content from a control level of 70.2 +/- 2.2 fmol/mg protein to 62.1 +/- 3.3 (-16%) at 10(-9) M, 52.3 +/- 5.3 (-25.5%; P < 0.02) at 10(-8) M, and 45.5 +/- 3.5 fmol/mg protein (-35.3%; P = 0.001) at 10(-7) M (n =...
Mechanisms of Angina in Aortic Stenosis

The pathophysiology of cardiac pain in pure aortic stenosis has primarily been ascribed to an augmented left ventricular demand outstripping energy supply. This report provides evidence that not only is the energy demand increased but the supply in terms of coronary vascular reserve may be impaired, particularly in response to stress. Hemodynamic and coronary circulatory changes were studied in 18 patients with aortic stenosis during standard isoproterenol infusion. It was not possible to differentiate any patient with or without angina pectoris or patients with or without coronary artery disease on a basis of change in any measure of left ventricular dynamics. On the other hand, differences did occur in the mechanisms of energy delivery during isoproterenol stress: (1) In group A (aortic stenosis without angina or coronary artery disease), coronary flow increased normally, myocardial oxygen extraction decreased, and myocardial lactate production occurred in only one of seven patients. This suggested that...
Free R value: a novel statistical quantity for assessing the accuracy of crystal structures.

THE determination of macromolecular structure by crystallography involves fitting atomic models to the observed diffraction data1. The traditional measure of the quality of this fit, and presumably the accuracy of the model, is theR value. Despite stereochemical restraints2, it is possible to overfit or 'misfit' the diffraction data: an incorrect model can be refined to fairly good R values as several recent examples have shown3. Here I propose a reliable and unbiased indicator of the accuracy of such models. By analogy with the cross-validation method4,5 of testing statistical models I define a statistical quantity (RfreeT) that measures the agreement between observed and computed structure factor amplitudes for a 'test' set of reflections that is omitted in the modelling and refinement process. As examples show, there is a high correlation between RfreeT and the accuracy of the atomic model phases. This is useful because experimental phase information is usually inaccurate, incomplete or unavailable. I expect that RfreeT will provide a measure of the information content of recently proposed models of thermal motion and disorder6–8, time-averaging9 and bulk solvent10.
Features of Transmembrane Segments That Promote the Lateral Release from the Translocase into the Lipid Phase

Topogenic sequences direct the membrane topology of proteins by being recognized and decoded by integral membrane translocases. In this paper, we have compared the minimal sequence characteristics of helical-hairpin, reverse signal-anchor, and stop-transfer sequences in bacterial membrane proteins that use either the YidC or SecYEG translocases for membrane insertion. We find that a stretch composed of 3 leucines and 16 alanines is required for efficient membrane-anchoring of the M13 procoat protein that inserts by a helical hairpin mechanism, and that a stretch composed of only 19 alanines has a detectable membrane-anchoring ability. Similar results were obtained for the reverse signal-anchor sequence of the single-spanning Pf3 coat protein and for stop-transfer segments engineered into leader peptidase. We have also determined the contribution to the apparent free energy of membrane insertion of M13 procoat for all 20 amino acids. The relative order of the contributions is similar to that determined for a stop-transfer sequence in the mammalian endoplasmic reticulum, but the absolute difference between the contributions for the most hydrophobic and most hydrophilic residues is somewhat larger in the E. coli system. These results are significant because they define the features of a membrane protein transmembrane segment that induce lateral release from the YidC and Sec translocases into the lipid bilayer in bacteria.
How Mitochondrial Structure Can Affect Energy Metabolism: Insights From Electron Microscopic Tomography

The idea that the internal structure of mitochondria might influence energy metabolism has its origins in electron microscopic studies in the 1960s and 1970s of morphologic changes during respiratory state transitions and ligand binding to adenine nucleotide translocator. In the ensuing years, the variety of known morphologic transitions displayed by mitochondria, in test tubes and in cells, has increased, as has information about the corresponding three-dimensional membrane topologies, provided by electron tomography. Experiments and simulations indicate that mitochondrial inner-membrane topology influences mitochondrial metabolic rates and other functions by altering internal diffusion pathways for ions, metabolites and soluble proteins. At the same time, the roles of certain proteins (e.g. ATP synthase) and lipids (e.g. cardiolipin) in determining inner-membrane topology are being uncovered. The emerging hypothesis is that mitochondrial inner-membrane topology is regulated by the cell to optimize mitochondrial performance in response to different stimuli (such as metabolite concentrations, apoptotic signals, and reactive oxygen). As techniques for cryo-specimen preparation (e.g. using focused ion beams) and imaging improve, it will become possible to apply electron tomography to whole cells and tissues in near-native, frozen-hydrated state. These enhanced imaging capabilities should provide new information about not only in-situ membrane topology, but also the nature of the physical contacts between mitochondrial outer and inner membranes; the nature of the tethers that regulate the spacing between mitochondria and endoplasmic reticulum (which in turn regulates mitochondrial calcium uptake, which in turn activates matrix dehydrogenases); the organization of the mitochondrial matrix; and possibly even the structure of respiratory supercomplexes in the mitochondrial inner membrane. (The Resource for Visualization of Biological Complexity is supported as an NCRR Biomedical Technology Research Resource by NIH grant P41-RR01219.)
Hereditarily finite representations of natural numbers and self-delimiting codes

Using a bijection between natural numbers and hereditarily finite functions we derive a new reversible variable length self-delimiting code through a bitstring representation in a balanced parenthesis language. The code features the ability to encode arbitrarily nested data types, can represent huge (low "complexity") numbers, and is decodable from its beginning or its end. Besides its possible practical applications to media stream encodings, a comparison with the well-known Elias omega code and a conjecture about its asymptotic behavior under the Kraft inequality suggest it as an interesting object of study for experimental mathematicians.The paper is organized as a self-contained literate Haskell program inviting the reader to explore its content independently. Its code is available at http://logic.cse.unt.edu/tarau/research/2010/selfdelim.hs
A predictive contact reliability model for MEM logic switches

Micro-electro-mechanical (MEM) switches are of interest for ultra-low-power electronics applications [1–5] because they offer the ideal characteristics of zero off-state leakage and abrupt switching behavior. The endurance of these devices can be limited by Joule heating at the contacting asperities (Figs. 1 and 2) which eventually leads to welding-induced failure. To provide guidance for reliable MEM switch design, a predictive contact reliability model is developed and validated in this work. The results show that device endurance depends not only on the contact material, but also on the operating voltage, series resistance, load capacitance, and logic style. Using the reliability model, endurance exceeding 1015 on/off cycles is projected for a scaled MEM switch technology operating at 1V.
An integrated organic circuit array for flexible large-area temperature sensing

Traditionally, several technologies have been used for temperature sensing, including integrated silicon ^#x0394;V BE and #x0394;V t circuits, resistance temperature detectors, and thermocouples [1]. The organic thin-film transistor (OTFT) is a new technology suitable for temperature sensing because of two key advantages. First, OTFTs have the ability to be fabricated on flexible and large-area substrates [2]. This ability allows an OTFT temperature sensor to be used for applications such as electronic skin, biomedical thermal imaging, and structural temperature monitoring [2]. Second, the OTFT's semiconductor trap states make OTFTs highly responsive to temperature. This paper presents the first integrated OTFT temperature sensing circuit array. The array is compatible with flexible and large-area substrates, and its outputs are 22 times more responsive than the MOSFET implementation while dissipating 90nW of power per cell.
Physico-chemical and morphological characteristics of avian encephalomyelitis virus

Abstract Avian encephalomyelitis virus (AEV) was purified from infected chick embryos by a gradient centrifugation in cesium chloride. The virus had a buoyant density of 1.31 to 1.32 g/ml and a sedimentation coefficient of 148 S. The purified AEV was resistant to treatments with chloroform, acid pH or trypsin. The presence of Mg ++ stabilized the virus against heat inactivation (56°C, 1 h). Electron microscopic study showed the virus to be 24 to 32 nm in diameter. The surface structure of the purified virus was not easily discernable. Nevertheless, with uranyl acetate-stained particles, Markham's rotation technique revealed that AEV has five-fold symmetry with 32 or 42 capsomers. Exact classification of AEV awaits characterization of the viral nucleic acid.
An approximation algorithm for the generalized assignment problem

The generalized assignment problem can be viewed as the following problem of scheduling parallel machines with costs. Each job is to be processed by exactly one machine; processing jobj on machinei requires timep ij and incurs a cost ofc ij ; each machinei is available forT i time units, and the objective is to minimize the total cost incurred. Our main result is as follows. There is a polynomial-time algorithm that, given a valueC, either proves that no feasible schedule of costC exists, or else finds a schedule of cost at mostC where each machinei is used for at most 2T i time units. We also extend this result to a variant of the problem where, instead of a fixed processing timep ij , there is a range of possible processing times for each machine—job pair, and the cost linearly increases as the processing time decreases. We show that these results imply a polynomial-time 2-approximation algorithm to minimize a weighted sum of the cost and the makespan, i.e., the maximum job completion time. We also consider the objective of minimizing the mean job completion time. We show that there is a polynomial-time algorithm that, given valuesM andT, either proves that no schedule of mean job completion timeM and makespanT exists, or else finds a schedule of mean job completion time at mostM and makespan at most 2T.
Genetic analysis of breast cancer progression.

At the histological level, breast tumors display a variety of morphologic lesions which suggest the existence of an increasingly aberrant pathway of intermediate steps leading to the invasive primary tumor and its metastatic dissemination. In order to obtain direct evidence for this presumed progression, underlying genetic changes must be identified. Analyses of primary breast tumors have revealed a large number of dominant and recessive gene alterations encompassing several cellular attributes and activities. It is quite likely that some of these alterations are of a causal nature and thus enable the tumor to attain distinctive malignant phenotypes, such as, dysregulated proliferation, invasion, angiogenesis, and ability to metastasize. Considerable heterogeneity has been observed in the sequence of acquisition of these genetic changes, which is substantiated by recent comparative analyses between carefully microdissected preinvasive and invasive tumor. The data are evaluated here in the context of existing models of breast cancer progression. Implications and prospects for translational application to the clinic are also discussed.
PTFE graft treated with silver norfloxacin (AgNF): drug retention and resistance to bacterial challenge.

Norfloxacin (NF) and silver norfloxacin (AgNF) were used to coat polytetrafluoroethylene (PTFE) vascular prostheses by using triododecylmethylammonium chloride as a cationic surfactant. The relative retention of the drug on the graft after subjecting it to the biological environment for 3 weeks and antibacterial activity against coagulase-positive Staphylococcus aureus and Escherichia coli were determined. In addition, the ability of AgNF-coated PTFE grafts to sterilize perigraft tissue after mixed bacterial contamination was studied and compared with control PTFE grafts in 10 dogs. At the end of 21 days, 15 and 18% of AgNF were retained on the grafts tested in in vitro and in vivo experiments, respectively. During the same time AgNF-coated grafts from in vitro experiments exhibited significant antibacterial activity (25 mm zone of inhibition (z.i.)), but antibacterial activity was negligible (10 mm z.i.) in the grafts from in vivo experiments. NF retention on the grafts could not be determined because of spectral interference by blood. The antibacterial activity of NF-coated grafts significantly declined after 24 hr in in vivo experiments, hence further evaluation of NF-coated grafts was not done. Seven perigraft sites surrounding AgNF-coated grafts were sterile, but only one perigraft site surrounding control grafts was sterile (P < 0.05). Cultures from six of nine perigraft infections surrounding control grafts yielded heavy bacterial growth. There was only one wound infection at the site of AgNF graft while there were seven severe wound infections at control graft sites. AgNF-coated grafts exhibited prolonged antibacterial activity compared to NF-coated grafts and offered significant protection against infection from local bacterial contamination.
Analysis of A, B, E, and F prostaglandins as pentafluorobenzyl esters by electron-capture gas-liquid chromatography

A new and sensitive method is described for the simultaneous analysis of a mixture containing PGE1, PGE2, PGF1alpha, and PGF2alpha by electron-capture gas-liquid chromatography. During derivatization of the mixture, PGE1 and PGE2 were converted to PGB1 and PGB2, respectively, yielding a mixture of PGB1, PGB2, PGF1alpha, and PGF2alpha trimethylsilyl ether pentafluorobenzyl esters. Gas chromatographic resolution of all four derivatives is sufficient for quantitation of each prostaglandin. The A prostaglandins were analyzed by similar conversion to the respective B prostaglandin derivatives. Minimum detection limits for the B and F prostaglandin derivatives were 10 pg and 1 pg, respectively. Samples of rabbit kidney medulla were incubated and analyzed for A, B, E, and F prostaglandins. The results indicate that the method is capable of high recovery and reproducibility.
Energy Level Pinning in Self-Assembled Alkanethiol Monolayers

Potassium deposition in ultrahigh vacuum on a self-assembled monolayer (SAM) of 1-dodecanethiol on Au(111) results in penetration of a large fraction of the metal to the gold−SAM interface, as dete...
The Relations of Ethnicity to Female Engineering Students' Educational Experiences and College and Career Plans in an Ethnically Diverse Learning Environment

This paper describes a mixed-methods study employing a social cognitive theoretical framework that emphasizes the interplay of person factors, environment, and behavior to explore the educational experiences of female students in an ethnically diverse learning environment. Specifically, we investigate the relations of ethnicity to female students' perceptions and experiences related to engineering, as well as their selection of and persistence in undergraduate engineering majors. An ethnically diverse sample of female engineering undergraduates at an urban research university completed an online survey and participated in semi-structured interviews. Results revealed that participants of all ethnicities perceived strong institutional and peer supports in this diverse learning environment. Additionally, differences in participants' perceived barriers for achieving engineering educational and career plans were found based on ethnicity and parental level of education.
Efficient and Explicit Coding for Interactive Communication

We revisit the problem of reliable interactive communication over a noisy channel, and obtain the first fully explicit (randomized) efficient constant-rate emulation procedure for reliable interactive communication. Our protocol works for any discrete memory less noisy channel with constant capacity, and fails with exponentially small probability in the total length of the protocol. Following a work by Schulman [Schulman 1993] our simulation uses a tree-code, yet as opposed to the non-constructive absolute tree-code used by Schulman, we introduce a relaxation in the notion of goodness for a tree code and define a potent tree code. This relaxation allows us to construct an explicit emulation procedure for any two-party protocol. Our results also extend to the case of interactive multiparty communication. We show that a randomly generated tree code (with suitable constant alphabet size) is an efficiently decodable potent tree code with overwhelming probability. Furthermore we are able to partially derandomize this result by means of epsilon-biased distributions using only O(N) random bits, where N is the depth of the tree.
Seasonal changes in the relationship between ornamentation and immune response in red jungle fowl

Resistance to disease is frequently suggested to be important in mate choice, but information about how immune status can be conveyed is lacking. During the breeding season, male red jungle fowl with large combs, a sexually selected trait, have lower levels of lymphocytes, but greater cell–mediated immunity, indicated by a cutaneous hypersensitivity response. Before the breeding season, however, both cell–mediated immunity and proportion of lymphocytes are positively correlated with comb length. Cell–mediated immunity is particularly important to jungle fowl during the breeding season, because the likelihood of injury during sexual competition is high and cell–mediated immunity is essential for healing wounds and resisting infection. This seasonal change in one aspect of immunity but not another suggests that the birds adaptively maintain certain immune system abilities, and that it can be misleading to use a single aspect of immune response in evaluating immunocompetence.
Toward a Unified Model of Information Systems Development Success

Information systems development ISD is a complex process involving interconnected resources, stake holders, and outcomes. Understanding factors contributing to ISD success has attracted keen interest from both researchers and practitioners, and many research studies have been published in this area. However, most studies focus on one or two factors affecting ISD success. A holistic view of factors impacting ISD success is missing. This paper synthesizes past research on the topic and proposes a unified model on ISD success through a systematic and comprehensive literature review. The unified model highlights that ISD is a complex and interactive process involving individual, team, and organization factors, as well as ISD methodology. These factors impact the ISD process as well as its success.
The Effect of Sharing Health Information on Teachers' Production of Classroom Accommodations.

Ninety elementary-school teachers read information about a hypothetical student experiencing school-related problems due to Type 1 diabetes mellitus (T1DM), generated classroom accommodations to assist the student, and rated their confidence in these accommodations. Each teacher was provided one of three levels of information about T1DM: (a) no disease information, (b) basic disease information, and (c) basic disease information + classroom implications. Providing teachers with more information about T1DM increased their ability to accommodate a student's learning needs. Similarly, a lower proportion of disease-specific accommodations were generated by teachers receiving no disease information (37%) than by teachers receiving basic disease information or basic disease information + classroom implications, and the later two groups were equivalent (47% for each). This study and future work concerning the effect of chronic illness on classroom performance and adjustment have implications for medical professionals, teachers, and school psychologists. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 553–564, 2006.
Derivation of the chiral Gross-Neveu spectrum for arbitrary SU(N) symmetry

Abstract The SU( N ) chiral invariant Gross-Neveu hamiltonian is diagonalized using iterated Bethe-ansatze. This extends to arbitrary N the results previously obtained for SU(2), and reproduces the spectrum obtained by assuming factorizability of the S -matrix.
Isolation of soluble immune complexes by affinity chromatography using staphylococcal protein A--Sepharose as substrate

This report describes a technique for the general isolation of immune complexes, based on a combination of gel filtration and affinity chromatography. The first step is the preparation of a globulin-enriched fraction by precipitation with ammonium sulfate at 50% saturation, or of an immune-complex-enriched fraction by precipitation with 5% polyethylene glycol 6000. The enriched fraction is then subfractionated by gel filtration in Ultrogel AcA 34. The immune complexes elute close to the void volume in the macroglobulin peak, separated from monomeric IgG molecules. This peak (sometimes subdivided into two fractions) is then submitted to affinity chromatography on a protein A--Sepharose cooumn. Most immune complexes contain IgG molecules and therefore bind to the column. Almost no protein is bound when normal serum is fractionated according to this method, and no immunoglobulins are detectable in the acid-eluted fraction from the protein A--Sepharose column. In two patients with soluble immune complexes in their sera we eluted immunoglobulin-containing fractions from the column; in one, these fractions had high rheumatoid factor titers; and in the second, with a clinical diagnosis of systemic lupus erythematosus, a similar fraction contained RNA.
Fluoroscopic angiography in the gross anatomy dissection laboratory: visualizing the aortic arch and its branches in a cadaver.

We present fluoroscopic images of the aortic arch and its branches obtained in a first year medical gross anatomy teaching laboratory after an aberrant right subclavian artery was discovered during dissection. The aortic arch and its branches in the cadaver were filled with contrast medium in molten agar. After the agar solidified, a portable fluoroscope was used to obtain radiographic images. These post-mortem images were then compared with computed tomography images obtained while the individual was living. The embryology, prevalence, and clinical findings of this arterial variation are reviewed, and the importance of recognizing the presence of an aberrant right subclavian artery before performing various procedures is discussed. This exercise gave students the unique opportunity to compare the three-dimensional anatomy seen in the dissection laboratory with the two-dimensional presentation of that same anatomy in the radiographic images that they will see in clinical practice. Clin. Anat. 24:253–257, 2011. © 2010 Wiley-Liss, Inc.
Potential role for a novel AP180-related protein during endocytosis in MDCK cells

Clathrin assembly protein, AP180, was originally identified as a brain-specific protein localized to the presynaptic junction. AP180 acts to limit vesicle size and maintain a pool of releasable syn...
The beginnings of hydrous mantle wedge melting

This study presents new phase equilibrium data on primitive mantle peridotite (0.33 wt% Na2O, 0.03 wt% K2O) in the presence of excess H2O (14.5 wt% H2O) from 740 to 1,200°C at 3.2–6 GPa. Based on textural and chemical evidence, we find that the H2O-saturated peridotite solidus remains isothermal between 800 and 820°C at 3–6 GPa. We identify both quenched solute from the H2O-rich fluid phase and quenched silicate melt in supersolidus experiments. Chlorite is stable on and above the H2O-saturated solidus from 2 to 3.6 GPa, and chlorite peridotite melting experiments (containing ~6 wt% chlorite) show that melting occurs at the chlorite-out boundary over this pressure range, which is within 20°C of the H2O-saturated melting curve. Chlorite can therefore provide sufficient H2O upon breakdown to trigger dehydration melting in the mantle wedge or perpetuate ongoing H2O-saturated melting. Constraints from recent geodynamic models of hot subduction zones like Cascadia suggest that significantly more H2O is fluxed from the subducting slab near 100 km depth than can be bound in a layer of chloritized peridotite ~ 1 km thick at the base of the mantle wedge. Therefore, the dehydration of serpentinized mantle in the subducted lithosphere supplies free H2O to trigger melting at the H2O-saturated solidus in the lowermost mantle wedge. Alternatively, in cool subduction zones like the Northern Marianas, a layer of chloritized peridotite up to 1.5 km thick could contain all the H2O fluxed from the slab every million years near 100 km depth, which suggests that the dominant form of melting below arcs in cool subduction zones is chlorite dehydration melting. Slab P–T paths from recent geodynamic models also allow for melts of subducted sediment, oceanic crust, and/or sediment diapirs to interact with hydrous mantle melts within the mantle wedge at intermediate to hot subduction zones.
Autonomy and ars moriendi

“How could her family just let her die? It's not their decision to make. Amanda's an adult—she's 23 years old—and if she wants a heart transplant, she should get it. It's her choice.” The meeting with Amanda and her parents in the ICU had just ended and I felt enormous sadness. Amanda and her mother had cried much of the time. Her father, visibly agitated, had stormed out halfway through the meeting. I'd sat in my office with the three of them many times before but we'd never had such a tense exchange. Lisa didn't know them the way I did. They were a fun-loving family who, until recently, had coped with Amanda's downturns reasonably well. I would have preferred some time alone to recover from the turmoil I felt, but Lisa, one of our best residents, needed to talk through what had just transpired. “I know it's not easy or straightforward, Lisa, but why do you feel so negatively toward Amanda's parents?” Lisa hesitated. “I'm really not sure—I know that they love her and have made a lot of sacrifices to care for her. But when I was alone with Amanda and explained that her heart wasn't strong enough to keep her alive, she said she didn't want to die. I think she wants a heart transplant. But you heard her parents. They're opposed. They want to take her home even though her cardiologist told them that Amanda would be dead within a matter of days. Amanda might live several years despite her Friedreich's ataxia if we restore her cardiac function. Knowing her prognosis, the transplant team pushed to get her to the top of the list for a new heart.” In the 10 years I had taken care of Amanda, I had learned a good deal about her …
Case report: Severe disseminated adenovirus infection in a neonate following water birth delivery

Adenovirus infections are a common cause of respiratory and enteric illnesses of late infancy and childhood. In neonates, adenovirus infections are rare, carrying a high morbidity and mortality rate. We present a case of infant who developed severe pneumonia and disseminated adenoviral infection following water birth delivery to a mother with gastroenteritis. The infant's infection was due to an adenovirus strain that has not been previously reported in neonates. J. Med. Virol. 85:667–669, 2013. © 2013 Wiley Periodicals, Inc.
Fludarabine therapy in Waldenström's macroglobulinemia

Abstract purpose: To assess the response rate, remission duration, and survival of patients with Waldenstrom's macroglobulinemia treated with the adenine nucleoside analogue fludarabine. patients and methods: Twenty-eight patients with Waldenstrom's macroglobulinernia, of whom only 2 were previously untreated, received fludarabine at a dose of 20 to 30 mg/m 2 intravenously daily for 5 days (20 patients) or 30 mg/m 2 intravenously daily for 3 days (8 patients). Treatment was continued until maximum response was achieved. Responding patients were followed with no further treatment until relapse. results: Ten patients responded (36%), including the 2 previously untreated patients and 8 of 26 patients (31%) who were resistant to prior therapies. Uninaintained remissions lasted for a median of 38 months. There were no fatalities associated with this treatment. Previously untreated patients and those with a primary resistant disease of relatively short duration were more likely to benefit from this treatment. conclusion: Fludarabine is an effective salvage agent for the treatment of patients with resistant Waldenstrom's macroglobulinemia. Further investigations of fludarabine in untreated patients and in combination with other active agents are warranted.
Cholesterol Embolism in Bone Marrow

Excerpt To the editor: In "Cholesterol Embolism: Diagnosis Antemortem by Bone Marrow Biopsy," in the December 1978 issue (1), Pierce and associates state that cholesterol emboli diagnosed by bone m...