cssi/SciSciGPT-SciSciNet huggingface dataset:
New derivation of the altarelli-Parisi equations

The Altarelli-Parisi equations are derived without using (1-z)/sub +/ regularization and delta(1-z) function insertion. We find that virtual diagrams from renormalization give a negative contribution to parton evolution and the effect of these virtual diagrams is equivalent to that of some real diagrams with opposite sign. In this new approach, momentum conservation and valence-quark-number conservation of parton-number densities are satisfied automatically. A consistent probabilistic picture of parton evolution inside a hadron is also given.
A simple model for forces between surfaces bearing grafted polymers applied to data on adsorbed block copolymers

Abstract We have developed a simple model for forces between adsorbed block copolymers based on terminally attached chains. From this model arises a pair of nondimensional variables, a dimensionless distance, ∂, and a dimensionless energy j . We scale our measurements on the forces between various di- and tri-block copolymers of styrene and vinyl pyridine adsorbed onto mica surfaces using these two dimensionless variables. All our data on block copolymer force-distance profiles falls reasonably well onto one universal curve in terms of ∂ and j .
Zeeman and dipolar coherences in dilute spin I = 32 powders. matrix-isolated CH3CN☆

Rare gas matrix isolation has been employed to observe static and dynamic effects on Zeeman and dipolar proton lineshapes of acetonitrile (CH3CN) at liquid helium temperatures. The increased resolution of powder patterns afforded by the elimination of intermethyl dipolar broadening makes it possible to observe the effects of pulse length spacing in solid echo and Jeener-Broekaert experiments. Analytical expressions for the responses of the I = 32 spin system to the pulse sequences have been derived to account for the observed effects in terms of the coherence mixing by the rf pulses. The rare gas environment also plays a role in the orientational ordering of the methyl group. Low barriers to internal rotational motion account for the appearance of a dynamic rotational polarization and a corresponding enhanced dipolar signal. A further consequence is unequal populations of I = 12 and 32 spir isomers, which is evident in the Zeeman lineshapes. The magnitude of the rotational barrier, approximated from the temperature dependence of the solid echo lineshapes, is of the order of 50 K.
Molecular marker incongruence in plant hybrid zones and phylogenetic trees

One of the striking observations from the young field of molecular evolutionary biology has been the high frequency of cases where taxon-specific markers are found to differ widely in both phylogenetic and geographic distribution. This pattern has been observed most frequently when cytoplasmic markers are compared with those of nuclear origin (Rieseberg & Soltis 1991), but similar observations are often made for comparisons among markers of nuclear origin only (Rieseberg & Ellstrand 1993). These observations are important to phylogenists because they provide ‘footprints’ of past evolutionary events, information that may be critical to elucidating true organismal phylogeny. Marker incongruence also is significant to the evolutionist because it may provide insights into the differences in the evolutionary biology of organellar versus nuclear genes (as well as differences among nuclear genes), the role of selection, linkage and recombination in controlling the frequency and spatial distribution of introgressed genes, and the effects of introgression on the maintenance of species differences. In this paper, we list some of the best examples of molecular marker incongruence from both hybrid zones and phylogenetic trees in plants. General patterns emerging from this tabulation are discussed, and possible explanations are briefly summarized. In addition, recent studies of differential introgression and its mechanistic basis in wild sunflowers of the genus Helianthus are reviewed in detail. Results from these studies appear to explain patterns of marker discordance in Helianthus, and possibly many other groups of plants as well.
Hydrodynamic Lubrication of Partial Porous Metal Bearings

Partial porous metal bearings performance during steady state operation with full film of lubricant, determining pressure distribution
A maize mutant with decreased capacity to accumulate chloroplast protein synthesis elongation factor (EF-Tu) displays reduced tolerance to heat stress

A chloroplast protein synthesis elongation factor, EF-Tu, accumulates in some maize (Zea mays L.) genotypes that show increased tolerance to heat stress [Planta 212 (2001) 359]. Previous studies, have suggested that maize EF-Tu may play a role in the development of heat tolerance [Plant Sci. 163 (2002) 1075]. In the present study, we identified a maize mutant that has decreased capacity to synthesize and accumulate EF-Tu under heat stress and tested the ability of the mutant to tolerate heat stress. Experiments were conducted in the laboratory using 17-day old plants. Stress tolerance was assessed by examining heat stability of photosynthetic membranes (thylakoids), thermal aggregation of chloroplast stromal proteins, and plant growth after exposure to stress. Compared to wild type (non-mutant), the mutant showed reduced tolerance to heat stress. Importantly, chloroplast stromal proteins from the EF-Tu-deficient mutant displayed greater aggregation during exposure to high temperature than chloroplast stromal proteins from the wild type. The results strongly support the hypothesis that maize EF-Tu plays a role in the development of heat tolerance by acting as a molecular chaperone and protecting chloroplast stromal proteins from thermal aggregation.
Confluent and reticulate papillomatosis (Gougerot-Carteaud syndrome): a minocycline-responsive dermatosis without evidence for yeast in pathogenesis. A study of 39 patients and a proposal of diagnostic criteria.

Summary Background Confluent and reticulate papillomatosis (CRP) (Gougerot–Carteaud syndrome) is a disorder that has been characterized in only small cohorts of patients. Objectives Better to characterize the clinical and pathological findings of the disorder. Methods We retrospectively reviewed the clinical presentation, response to treatment and histological findings of patients presenting to Mayo Clinic (Rochester, MN, U.S.A.) with CRP. Results The disorder was diagnosed in 39 patients between 1972 and 2003. Mean age at onset of the skin eruption was 15 years (range 8–32); 21 patients (54%) were male; most were white; most (33) presented for reasons of cosmesis; and eight described the rash as mildly pruritic. At presentation, the skin eruption had been present for a mean of 3·1 years (range 3 months−20 years) and had been recalcitrant to treatment, including antifungal treatment. Typical objective findings were scaling brown macules and patches and velvety papules and plaques, reticulated and papillomatous at least in part, involving the upper trunk, axillae and neck. The most frequent initial diagnostic impressions were tinea versicolor, acanthosis nigricans and CRP. Scales in 32 cases were examined with potassium hydroxide: eight (25%) showed hyphae, and 24 (75%) did not. Skin biopsy specimens from 21 patients showed variable degrees of hyperkeratosis, acanthosis and papillomatosis. Minocycline was prescribed for 22 patients, of whom 14 of 18 (78%) had complete clearing of the skin eruption and four (22%) a partial response. The skin eruptions recurred after stopping treatment in six patients. Conclusions CRP occurs predominantly in young adults and teenagers, with cosmetically displeasing brown scaling patches and plaques affecting the neck, upper trunk and axillae. Frequently, the diagnosis is delayed and the disorder not recognized by physicians, including dermatologists. Clinically, the eruption is most often confused with tinea versicolor. Potassium hydroxide staining of the scale is negative in the majority of cases, implying that fungi are not involved in the pathogenesis of this condition, as has been previously proposed. It is important to recognize this disorder, because minocycline therapy is highly effective in most patients. Criteria for the diagnosis are proposed.
Survival of Bovine Spermatozoa at Room Temperature in Citrate and Cornell University and Tris Extenders Containing Whole and Fractionated Coconut Milk

Summary The average percentage of motile sperm over an eight-day storage period in a citrate buffer alone or with the addition of 15% by volume of whole coconut milk (CM), neutral fraction (NF), and active fraction (AF), for carrot explants, or NF + AF was 19, 34, 42, 22, and 36, respectively. Corresponding values in Cornell University Extender (CUE) were, respectively, 44, 42, 44, 42, and 42% and for Tris (hydroxymethyl) aminomethane (Tris), 31, 32, 24, 32, and 30%. Whole coconut milk and the neutral fraction equally improved sperm survival in citrate buffer, but did not improve sperm survival in the other buffers. Removal of anions and cations from the NF reduced this response, but carbohydrates or other material, or both, remaining in the NF produced some effect. The fraction active in producing cell division in carrot explants was ineffective for sperm. In general, the CUE buffer was equal or superior to the other treatments tested, indicating that coconut milk had no special properties due to unknown substances. Sperm survival in all buffers was improved by the addition of egg yolk.
Patterns of prenatal care initiation in Georgia, 1980-1992.

Objective To determine whether characteristics in a woman's first pregnancy were associated with the trimester in which she initiated prenatal care in her second pregnancy. Methods Data for white and black women whose first and second pregnancies resulted in singleton live births between 1980 and 1992 were obtained from Georgia birth certificates ( n = 177,041). Adjusted relative risks (RRs) for early prenatal care in the second pregnancy were computed by logistic regression models that included trimester of prenatal care initiation, infant outcomes, or maternal conditions in the woman's first pregnancy as the exposure and controlled for maternal age, education, child's year of birth, interval between first and second pregnancy, presence of father's name on the birth certificate, and the interaction between prenatal care and education. Models were stratified by race. Results Women of both races who initiated prenatal care in the first trimester of their first pregnancies were more likely than those with delayed care to initiate prenatal care in the first trimester of their second pregnancies (RR = 1.25 and 1.63 for white and black women educated beyond high school, respectively). Both white and black women who delivered a baby with very low birth weight (RR = 1.06 and 1.15, respectively) or who suffered an infant death (RR = 1.09 and 1.31, respectively) in their first pregnancies were more likely than those who did not experience these events to begin prenatal care in the first trimester of their second pregnancies. Conclusion Women with some potentially preventable adverse infant outcomes tend to obtain earlier care in their next pregnancy. Unfortunately, women who delayed prenatal care in their first pregnancy frequently delay prenatal care in their next.
On the Heat Equation with a Time-Dependent Singular Potential☆

Abstract We introduce various classes of potentials on [0, T ]× R n and study the corresponding nonautonomous heat equation given by ∂u ∂t = 1 2 Δu−V(t,x)u. We prove the existence of the Feynman–Kac propagators for the nonautonomous heat equation and the ( L p − L q )-smoothing theorem for the propagators.
A computational and experimental study of high Reynolds number viscous/inviscid interaction about a cone at high angle of attack

The flow over a 5 deg semi-angle cone at incidence in supersonic flow is studied as a model problem for the flow over aircraft forebodies. A computational method utilizing the conically symmetric Navier-Stokes equations is used to obtain theoretical flow results which are compared with experimental data from the Ames Research Center 6- by 6-Foot Wind Tunnel and with results from a cone model sting mounted on an F-15 aircraft. The computed results agree well with the wind-tunnel data but less well with the flight data. Modification of the algebraic turbulence model was necessary to reflect an apparent lower turbulence level in flight than was present in the wind tunnel.
Exaggerated prostaglandin production by colonic smooth muscle in rabbit colitis.

Enhanced production of arachidonic acid metabolites by colonic mucosa has been reported in ulcerative colitis as well as in experimental models of colitis. However, production of these compounds by colonic smooth muscle from colitis subjects has not been described. To evaluate arachidonic acid metabolism in colonic tissue, we studied the production of prostaglandin E2 (PGE2) by mucosa and muscularis propria in two experimental models of acute colitis in which inflammation was virtually confined to the mucosa. Colitis was induced in New Zealand white rabbits by either of two methods, dinitrochlorobenzene (DNCB) sensitization or formalin followed by intravenous soluble immune complexes (F-IC). Arachidonic acid metabolites were identified from in vitro incubations of tissue with [14C]arachidonic acid by thin layer chromatography followed by autoradiography. The major eicosanoid metabolites of colitis mucosa and muscularis were14C-labeled prostaglandin E2, prostaglandin F2a and 6-keto prostaglandin f1a. PGE2 was quantitated from incubations without labeled arachidonic acid by radioimmunoassay. PGE2, expressed as picograms per milligram protein per 20 min (mean±sem), was increased in F-IC mucosa (1093±141 vs 645±189, P < 0.05) and DNCB mucosa (1354±487 vs 527±222, P < 0.05) compared to normals. PGE2 production by uninflamed colitis muscularis propria was also increased five-to eightfold compared to normals for F-IC muscularis (1594±329 vs 189±35, P < 0.005) and DNCB muscularis (1287±171 vs 225±72, P < 0.005). Thus, the adjacent inflammation in colonic mucosa may induce increased eicosanoid production by the uninflamed smooth muscle. Increased PGE2, in turn, may contribute to the smooth muscle dysfunction seen in colitis.
Capitalizing on AKT signaling to inhibit hepatocellular carcinoma cell proliferation.

Commentary to: Cyclic AMP Inhibition of Proliferation of Hepatocellular Carcinoma Cells Is Mediated by Akt Lunhua Liu, Yili Xie and Liguang LouVol: 4 | Issue: 11 | pgs: 1240-1247
Monte Carlo techniques in code optimization

Effective optimization of FPS Array Processor assembly language (APAL) is difficult. Instructions must be rearranged and consolidated to minimize periods during which the functional units remain idle or perform unnecessary tasks. Register conflicts and branches cause complications. Deterministic algorithms to arrange instructions traditionally use complex heuristics which are tailored to specific inputs. A non-deterministic approach can be simpler and effective on a large class of inputs. This is a progress report on the “Monte Carlo” optimizer under construction at Cornell University by the authors. This optimizer randomly modifies the text of an APAL program without changing its meaning. Modifications which improve the program are favored. A set of six elementary transformations are the basis for modifications.
Target estimation in colocated MIMO radar via matrix completion

We consider a colocated MIMO radar scenario, in which the receive antennas forward their measurements to a fusion center. Based on the received data, the fusion center formulates a matrix which is then used for target parameter estimation. When the receive antennas sample the target returns at Nyquist rate, and assuming that there are more receive antennas than targets, the data matrix at the fusion center is low-rank. When each receive antenna sends to the fusion center only a small number of samples, along with the sample index, the receive data matrix has missing elements, corresponding to the samples that were not forwarded. Under certain conditions, matrix completion techniques can be applied to recover the full receive data matrix, which can then be used in conjunction with array processing techniques, e.g., MUSIC, to obtain target information. Numerical results indicate that good target recovery can be achieved with occupancy of the receive data matrix as low as 50%.
Phase matching in cascaded third-order processes

We present an analytical, computational, and experimental study of frequency mixing and propagation that takes place in the guided-wave nonlinear frequency conversion of ultrashort pulses from the near infrared to the far and the vacuum ultraviolet. In addition to the standard phase-matching conditions for frequency mixing, we observe that cascaded frequency conversion, in which one of the input frequency components is generated simultaneously, is subject to two additional phase-matching conditions. In cascaded quasi-phase matching, one of the input fields oscillates in strength with a period that matches the phase mismatch. In gain-assisted phase matching, the growth of one of the input fields results in growth of the signal, in spite of a phase mismatch for the final mixing process.
Degradation Chemistry of Gemcitabine Hydrochloride, a New Antitumor Agent

The anti-tumor agent gemcitabine hydrochloride, a beta-difluoronucleoside, is remarkably stable in the solid state. In 0.1 N HCI solution at 40 degrees C, deamination of gemcitabine occurs, yielding its uridine analogue. Approximately 86% of the initial gemcitabine remains after 4 weeks under these conditions. Cleavage of the N-glycosidic bond of gemcitabine or conversion to its alpha-anomer in 0.1 N HCI solution is not observed over a 4-week period. However, this work has shown that gemcitabine hydrochloride anomerizes in 0.1 N NaOH at 40 degrees C. Approximately 72% of the initial gemcitabine remains after 4 weeks under the basic conditions used. Uridine hydrolysis products are also formed under these conditions. The anormerization reaction, which is unusual under basic conditions, has been confirmed by characterization of the chromatographically isolated alpha-anomer by NMR and mass spectrometry. A mechanism involving an acyclic intermediate is proposed.
Genomics and the physiologist: bridging the gap between genes and crop response

Plant physiologists have traditionally studied the relationship between crop performance (the phenotype) and the environment. Global change processes present multiple challenges to crop performance that can be met effectively by changing the crop environment through management, and by modifying the crop genome (the genotype) through plant breeding and molecular biology. In order to increase the reliability of crop performance prediction based upon genetic information, new tools are needed to more effectively relate observed phenotypes to genotypes. The emerging discipline of genomics offers promise of providing such tools, and may provide a unique opportunity to enhance genetic gains and stabilize global crop production. Genomics has developed from the confluence of genetics, automated laboratory tools for generating DNA- and RNA-based data, and methods of information management. Functional genomics concentrates on how genes function, alone and in networks, while structural genomics focuses on physical and structural aspects of the genome. The traditional strengths of physiology lie in interpreting whole plant response to environmental signals, dissecting traits into component processes, and predicting correlated responses when genes and pathways are perturbed. These complement information on the genetic control of signal transduction, gene expression, gene networks and candidate genes. Combining physiological and genetic information can provide a more complete model of gene-to-phenotype relationships and genotype-by-environment interactions. Phenotypic screening procedures that more accurately identify underlying genetic variation, and crop models that incorporate Mendelian genetic controls of key processes provide two tangible examples of fruitful collaboration between physiologists and geneticists. These point to a productive complementary relationship between disciplines that will speed progress towards stable and adequate food production, despite challenges posed by global climate change.
The Boundary Between Module Interface and the SCA in the GRA

This paper describes a view of the boundary between the GRA specification (terminal level) and the module specification (module level) and its relationship to the use of Software Communications Architecture (SCA) Framework. The primary goals of the GRA are to foster competition by enabling 3rd party development of GRA modules, to use future technology innovatively in those modules, to enable the use of COTS and GOTS products and to realize an efficient terminal implementation using those modules. The architecture must be specified as a set of independent modules that have low coupling and high cohesion to achieve these goals. This allows modules with varying implementations to be used in the system with no or minimal changes. Partitioning of the modules must assure that internal module implementations are free to use the most efficient design and technology to provide the best performance and cost benefits. The view is presented that the SCA is a mechanism that provides the framework for a set of independent modules to use to work together to implement a High Capacity Communications Capability (HC3) system. The use of the SCA internal to the modules should be left up to the module implementer and hidden (decoupled) from the rest of the system
Foveal task effects on same-different judgments in the visual periphery

An attempt was made to examine the extent to which the presence of a foveal stimulus affects same-different judgments regarding the horizontal-vertical orientation of two lines located in peripheral vision. The results of the study indicated that accuracy in reporting peripheral visual stimuli is determined not only by the nature of those stimuli, but also by whether other stimuli are presented foveally. The simultaneous presence of another stimulus in foveal vision reduces accuracy in reporting peripheral stimuli, independent of instructions to ignore, detect, or identify the foveal stimulus.
Teaching in amazon EC2

As the trend of IT service consolidation continues to rise, organizations are now looking at hosting their services in the cloud to cut back on the costs of hosting their information systems locally. This presents an opportunity and challenge for higher learning institutions to prepare their students for the technology skills that are going to be in demand upon their graduation. In many aspects universities are already using virtual environments to teach many laboratory courses for distance students. However there is the need to introduce students to industry standard services that will better acquaint them with what is currently being used in the real world. This poster takes a look at the course 'Principles of System Administration' from the Networking Security and System Administration Department at Rochester institute of Technology and creates a foundation for moving the course over to the cloud using Amazon Web Services. It analyzes various cost scenarios, shortfalls of Amazon EC2 as a teaching platform, and proposes building a custom management system to better handle permissions.
Greedy Matching in Young's Lattice

If the level sets of a ranked partially ordered set are totally ordered, the greedy match between adjacent levels is defined by successively matching each vertex on one level to the first available unmatched vertex, if any, on the next level. Aigner showed that the greedy match produces symmetric chains in the Boolean algebra. We extend that result to partially ordered sets which are products of chains.
Lower crustal flow and the role of shear in basin subsidence: an example from the Dead Sea basin

Abstract We interpret large-scale subsidence (5–6 km depth) with little attendant brittle deformation in the southern Dead Sea basin, a large pull-apart basin along the Dead Sea transform plate boundary, to indicate lower crustal thinning due to lower crustal flow. Along-axis flow within the lower crust could be induced by the reduction of overburden pressure in the central Dead Sea basin, where brittle extensional deformation is observed. Using a channel flow approximation, we estimate that lower crustal flow would occur within the time frame of basin subsidence if the viscosity is ≤7×1019–1×1021 Pa s, a value compatible with the normal heat flow in the region. Lower crustal viscosity due to the strain rate associated with basin extension is estimated to be similar to or smaller than the viscosity required for a channel flow. However, the viscosity under the basin may be reduced to 5×1017–5×1019 Pa s by the enhanced strain rate due to lateral shear along the transform plate boundary. Thus, lower crustal flow facilitated by shear may be a viable mechanism to enlarge basins and modify other topographic features even in the absence of underlying thermal anomalies.
Characterization of virtual coupling in the proton nuclear magnetic resonance spectrum of N,N'-diacetylchitobiose by two-dimensional J-resolved spectroscopy.

Abstract The anomeric proton of the reducing N-acetylglucosamine residue of β-N,N′-diacetylchitobiose exhibited an unusual lineshape indicative of virtual coupling in the 250 MHz proton NMR spectrum. The two-dimensional J-resolved spectrum contained four lines associated with this proton, and this pattern can be used to distinguish virtual coupling from other effects. Anomeric protons of previously studied asparagine-linked glycopeptides which exhibited unusual lineshapes in the conventional NMR spectra did not exhibit the four line patterns indicative of virtual coupling in the two-dimensional J-resolved spectra. Although virtual coupling may partially account for the unusual lineshapes observed in the normal proton NMR spectra, the anomalous behavior observed in the two-dimensional J-resolved spectra of these glycopeptides cannot be explained solely by this phenomenon.
The role of endoscopic choroid plexus coagulation in the surgical management of bilateral choroid plexuses hyperplasia

Background Bilateral choroid plexus hyperplasia is a rare condition often associated with cerebrospinal fluid (CSF) overproduction. CSF overproduction is usually so high that the placement of a CSF ventriculoperitoneal shunt almost always results in progressive ascites leading to the necessity of removing the inserted shunt device. A direct surgical treatment of the hyperplastic choroid plexuses is then mandatory. Endoscopic coagulation of the choroid plexuses has been recently proposed as an alternative to open surgical plexectomy. However, the effectiveness of the procedure in controlling CSF overproduction is still debated.
Repair System for Noncanonical Purines in Escherichia coli

Exposure of Escherichia coli strains deficient in molybdopterin biosynthesis (moa) to the purine base N-6-hydroxylaminopurine (HAP) is mutagenic and toxic. We show that moa mutants exposed to HAP also exhibit elevated mutagenesis, a hyperrecombination phenotype, and increased SOS induction. The E. coli rdgB gene encodes a protein homologous to a deoxyribonucleotide triphosphate pyrophosphatase from Methanococcus jannaschii that shows a preference for purine base analogs. moa rdgB mutants are extremely sensitive to killing by HAP and exhibit increased mutagenesis, recombination, and SOS induction upon HAP exposure. Disruption of the endonuclease V gene, nfi, rescues the HAP sensitivity displayed by moa and moa rdgB mutants and reduces the level of recombination and SOS induction, but it increases the level of mutagenesis. Our results suggest that endonuclease V incision of DNA containing HAP leads to increased recombination and SOS induction and even cell death. Double-strand break repair mutants display an increase in HAP sensitivity, which can be reversed by an nfi mutation. This suggests that cell killing may result from an increase in double-strand breaks generated when replication forks encounter endonuclease V-nicked DNA. We propose a pathway for the removal of HAP from purine pools, from deoxynucleotide triphosphate pools, and from DNA, and we suggest a general model for excluding purine base analogs from DNA. The system for HAP removal consists of a molybdoenzyme, thought to detoxify HAP, a deoxyribonucleotide triphosphate pyrophosphatase that removes noncanonical deoxyribonucleotide triphosphates from replication precursor pools, and an endonuclease that initiates the removal of HAP from DNA.
Calculating Seebeck Coefficients for Arbitrary Temperature Gradients

A novel computational scheme has been used to predict the electric potentials generated by arbitrary temperature gradients in semiconductor materials. Written in object-oriented code, the Discrete State Simulation (DSS) is a coupled cellular automata simulator that builds upon the objects and rules of quantum mechanics. The DSS represents global non-equilibrium processes as patterns that emerge through an ensemble of scattering events that are localized at vibronic nodes. By tracking the energy-momentum-position coordinates of the individual particles that define the vibronic state at a node, the DSS undercuts equilibrium concepts such as temperature. Consequently, the DSS can represent physical systems that are described by more than one temperature or that contain physical features that defy definitions of temperature. Using modified bootstrap sampling algorithms, the DSS depicted (1) shifts in distribution functions induced by external fields and temperature gradients, (2) field-dependent transitions from linear mobility to non-linear mobility, (3) saturation velocities, (4) non-exponential decay functions generated by multiple phonon scattering modes, and (5) charge separations and electric potentials generated by temperature gradients. Ensemble averages were sensitive to the structure of dispersion relations, to the energy of the system, and to quantum coupling strengths. Seebeck coefficients were sensitive to the features of the electronic and the vibrational band structures, and their associated coupling coefficients.
Bacterial cell-to-cell signaling in the gastrointestinal tract.

The gastrointestinal (GI) tract is the site of the largest and most complex environment in the mammalian host. In the adult human, the total microbial population (ca. 1014 cells) is estimated to exceed the total number of mammalian cells by at least an order of magnitude ([5][1]). The GI tract
Accelerated enlargement of experimental abdominal aortic aneurysms in a mouse model of chronic cigarette smoke exposure.

Background Cigarette smoking and pulmonary emphysema are strongly associated with abdominal aortic aneurysms (AAAs), but the biologic mechanisms linking these conditions are undefined. Study design To determine if exposure to cigarette smoke influences formation and growth of experimental AAAs, 129/SvEv mice were acclimated to daily cigarette smoke exposure for 2 weeks followed by transient elastase perfusion of the abdominal aorta to induce aneurysmal degeneration. Smoking was continued for intervals of either 2 or 12 weeks (8 mice per group). Nonsmoking 129/SvEv controls (n = 29) underwent elastase perfusion and followup evaluation at the same time intervals. In all animals, abdominal aortic diameter (AD) was measured to determine interval increases in AD (ΔAD), with AAAs defined as a ΔAD > 100%. Results Preperfusion and immediate postperfusion ADs were not significantly different between experimental groups. Aneurysmal dilatation was present 2 weeks after elastase perfusion in both smoking mice and nonsmoking controls, with no significant difference in final AD (mean ± SEM: smoking, 1.23 ± 0.11 mm versus nonsmoking, 1.22 ± 0.05 mm). There were also no differences in the overall extent of aortic dilatation (ΔAD smoking, 136 ± 24% versus nonsmoking, 138 ± 10%), or the incidence of AAAs (smoking, 75% versus nonsmoking, 79%). Although all animals had developed AAAs by 12 weeks after elastase perfusion, the overall extent of aortic dilatation was 50% greater in smoking mice compared with nonsmoking controls (ΔAD smoking, 204 ± 23% versus nonsmoking, 135 ± 17%; p Conclusions Short-term exposure to cigarette smoke did not alter initial development of experimental AAAs, but chronic smoke exposure was associated with a substantial increase in the late progression of aneurysmal dilatation. This novel combination of in vivo experimental models offers a new approach to investigate mechanisms by which cigarette smoking promotes aneurysmal degeneration.
Dynamic influences of nutrients and grazing fish on periphyton during recovery from flood

AbstractNutrients and grazers both can regulate benthic algal structure and function in streams, but the relative strength of each factor depends on stream biotic and abiotic conditions. The abundance of stream organisms and nutrient availability can change rapidly after a flood. Thus, nutrient and grazer influences on algal development and how these drivers interact may vary temporally during recovery. We measured benthic structural and functional development for 35 d after a simulated flood in large outdoor mesocosms under a gradient of 6 nutrient loadings crossed with 6 densities of grazing fish (Southern redbelly dace, Phoxinus erythrogaster). Nutrients influenced algal development more than dace did and were better correlated with algal function (area-specific primary productivity and nutrient uptake) than with structure (biomass). Dace influenced all structural variables and biomass-specific gross primary productivity, but their influence was relatively weak and was observed only early in recovery. ...
Artificial intelligence-assisted occupational lung disease diagnosis

An artificial intelligence expert-based system for facilitating the clinical recognition of occupational and environmental factors in lung disease has been developed in a pilot fashion. It utilizes a knowledge representation scheme to capture relevant clinical knowledge into structures about specific objects (jobs, diseases, etc) and pairwise relations between objects. Quantifiers describe both the closeness of association and risk, as well as the degree of belief in the validity of a fact. An independent inference engine utilizes the knowledge, combining likelihoods and uncertainties to achieve estimates of likelihood factors for specific paths from work to illness. The system creates a series of "paths," linking work activities to disease outcomes. One path links a single period of work to a single possible disease outcome. In a preliminary trial, the number of "paths" from job to possible disease averaged 18 per subject in a general population and averaged 25 per subject in an asthmatic population. Artificial intelligence methods hold promise in the future to facilitate diagnosis in pulmonary and occupational medicine.
Organization Structure, Individual Attitudes and Innovation

Innovation (the initiation, adoption and implementation of new ideas or activity in an organizational setting) is reviewed in terms of organization context, structure, and member attitudes. A series of propositions and three predictive models are derived and presented as directions for future research and theory construction.
Standing in the Way of Privacy Protections: The Argument for a Relaxed Article III Standing Requirement for Constitutional and Statutory Causes of Action

This note considers the appropriateness of current jurisprudence applying Article III’s injury-in-fact standing requirement to Constitutional and statutory privacy causes of action. It concludes that requiring a separate showing of injury-in-fact for these cases undercuts the goals of Article III standing; courts should instead consider violation of the underlying privacy cause of action to be sufficient injury-in-fact to grant Article III standing.
Interferometric SAR images from holographic SAR data

Over the last two years the Houston Advanced Research Center (HARC) has been working to bring together three areas of investigation to advance the understanding of the electromagnetic scattering process and create usable images from the received data. Those areas include real vegetation and computer modeling of various vegetation environments, constructing computer facet models of various objects of interest with surrounding terrain, and wideband holographic synthetic aperture radar (HSAR) measurements. Recently work has been done using HSAR data to produce interferometric SAR (IFSAR) images containing height information of the illuminated terrain and objects of interest. Analysis of height information allows another use for HASR data and provides additional dimensional information besides the 3D information already available from standard HSAR algorithms. >
Coloring-book-type experiences and children's divergent pictorial production☆

Abstract Sixty-four children in kindergarten and first grade were asked to color one of three pictures which varied in complexity. Following the coloring exercise the children were administered the CIRCUS: Make a Tree , a measure of divergent pictorial production which yields three scores (Appropriateness, Unusualness, Difference). A one-way ANOVA revealed a main effect of the coloring exercise in Unusualness and Difference. The findings suggest that giving children models to color can increase the novelty displayed in their subsequent productions, and that giving children complex models to color can increase the variety displayed in the pictures that they make. The findings are consistent with Gardner's (1980) suggestion that adult models can contribute to the substance of the child's pictoral productions by providing new ideas and information about how to achieve desired effects, and that they do not necessarily induce the slavish copying feared by many early childhood- and art-educators.
Duplexing, multiplexing, and multiple access: A comparative analysis for mesh networks

Wireless mesh networks have seen much attention in recent years, and are still a topic of much interest. These networks have application in tactical military systems as well as commercial systems. The question of which duplexing, multiplexing, and multiple access techniques are preferable for mesh networks is also a subject of some study, but this particular topic has seen surprisingly little attention. It appears that time-division, or ldquoburstedrdquo waveforms are currently favored in many systems. In this paper we provide a basic comparison of time, frequency, and time-frequency schemes, highlighting their similarities and differences. We also provide a straightforward analysis of network capacity, with results that indicate that time-frequency approaches may be superior to the other more commonly employed techniques in some cases, such as for long-range, high data rate networks.
Public Railroad Construction and the Development of Private Enterprise in the South Before 1861

The paper is based upon research over a rather long period into the public activities in railroad construction in the southern states. Table I-A presents a quantitative summary of public contributions in cash, bonds, and other securities; government-endorsed bonds; remission of Federal import duties; and estimated realized values of Federal land grants prior to 1861. It represents an attempt to give a preliminary summary of the public effort. The estimates on public land grants are tentative, and other items are subject to further refinements through additional studies. It does not represent the total of the public effort, since no account is taken in this summary of the investment values of the many important public and quasi-public contributions in services, the uses of public streets and other properties, tax exemptions, and banking privileges. An adequate appraisal of these must await further research. The summary does reflect, however, some of the outstanding features of the public railroad-building effort, which will supply a useful background for the consideration of the main problem of this paper.
Unifying Non-Maximum Likelihood Learning Objectives with Minimum KL Contraction

When used to learn high dimensional parametric probabilistic models, the classical maximum likelihood (ML) learning often suffers from computational intractability, which motivates the active developments of non-ML learning methods. Yet, because of their divergent motivations and forms, the objective functions of many non-ML learning methods are seemingly unrelated, and there lacks a unified framework to understand them. In this work, based on an information geometric view of parametric learning, we introduce a general non-ML learning principle termed as minimum KL contraction, where we seek optimal parameters that minimizes the contraction of the KL divergence between the two distributions after they are transformed with a KL contraction operator. We then show that the objective functions of several important or recently developed non-ML learning methods, including contrastive divergence [12], noise-contrastive estimation [11], partial likelihood [7], non-local contrastive objectives [31], score matching [14], pseudo-likelihood [3], maximum conditional likelihood [17], maximum mutual information [2], maximum marginal likelihood [9], and conditional and marginal composite likelihood [24], can be unified under the minimum KL contraction framework with different choices of the KL contraction operators.
Simulation of the Influence of Aspect Ratio on the Aerodynamics of Rectangular Prisms

AbstractA numerical simulation of three-dimensional flow around rectangular prisms (two dimensional) of different aspect ratios, ranging from 0.3 to 7.0, is conducted at a Reynolds number of 105, using large eddy simulation. This study identifies the influence of aspect ratio on the flow field around prisms and the attendant aerodynamics. Results show salient features in the flow field and associated pressure/aerodynamic forces caused by changes in the afterbody, which demonstrate good agreement with observations from wind tunnel experiments. A time-frequency analysis is introduced to identify the transient nature of fluctuations in the drag and lift coefficients, highlighting temporal variations in the frequency contents of these fluctuations and their resulting influence on force coefficients.
Impact of asymmetric traffic densities on delay tolerant vehicular ad hoc networks

Vehicular networking can be achieved with short, medium, or long-range communication technologies. However, there are trade-offs in the adoption of these technologies including data capacity, continuity of connections, energy use and contention with other users. We focus on short range technologies that support both near-neighbor communication, for safety applications, and multihop communications for message propagation. Due to frequent network partitioning, opportunistic message exchange is required for message propagation. Earlier studies reveal that messages are suitably propagated in both directions of traffic as vehicle traffic density increases. In this paper we consider asymmetries in traffic density caused by directionality. For example, ‘rush hour’ traffic fills one direction of a roadway while the other direction can be sparse. Performance analysis indicates that data dissemination under asymmetry produces a corresponding asymmetry in message propagation in the direction of higher-density traffic. This result is framed in the context of traffic density regimes and is useful in the design of vehicular networks that leverage short range communications. For a fixed traffic density in one direction, an increase in density from 0 to 20 vehicles/km in the other direction, yields a corresponding increase of 500 m/s to 1000 m/s in the messaging performance depending upon the regime.
Genetic algorithm synthesis of planar zero index metamaterials for the infrared with application to electromagnetic cloaking

A planar metamaterial structure using a single Ag FSS screen sandwiched between layers of polyimide was proposed that is straightforward to fabricate. This structure was optimized by a GA to have a low/zero index of refraction with high transmission in the far-IR. Measured dielectric and metallic properties incorporation into the model provide confidence that the PMM predictions are accurate. Fabrication constraints in the GA ensured that the design result can be fabricated. Experimental efforts are currently underway to characterize this design for the predicted ZIM properties.
Packet transmission policies for battery operated communication systems

In this paper, we address the problem of designing battery-friendly packet transmission policies for wireless data transmission. Our objective is to maximize the lifetime of battery for wireless devices subject to certain delay constraints. We present three packet transmission schemes and evaluate them with respect to battery performance. The first scheme based on combining multiple packets, utilizes the battery charge recovery due to long idle periods. The second scheme based on a modified version of lazy packet scheduling, draws lower current and is battery efficient. The third scheme which is based on a combination of the above two schemes, has superior battery performance at the expense of larger average packet delay. All three schemes were simulated for a wireless communication framework with Internet traffic, and the results validated.
Time for a Change.

As my tenure as journal editor comes to a close at the end of December, I felt compelled to sharewith our readership a few finalwords. It has been an educational and interesting opportunity to have been chosen as the editor by Cathy DeAngelis, MD,more than 10 years ago and to be able to continue in that role under her successor, Howard Bauchner, MD. During this period, the changes in the journal and those of the JAMA Network have mirrored those of organized medicine, focusing on systems, standardization, and the increasing use of computer technology. Iwas given theopportunity to assist inmaking the reworking of our journal a reality and learning along the way of the complexities, challenges, and the future of producing a medical publication that is contemporary and educational. Our journal and the Network to which it belongshavebecomequite facile inadjusting to thechangingeducational needs and learning styles of themodern physician. For a busy academic head and neck surgeon and department chairman, the responsibilities of editor of JAMAOtolaryngology–HeadN George Zalzal, MD; Tim Smith, MD, MPH; and Craig Buchman, MD; as well as my section editors Mark Jameson, MD, PhD;DougMattox,MD;EdStelow,MD;DougPhillips,MD;and more recentlyBeckyCornelius,MD;BoydGillespie,MD,MSc; AlMerati,MD; andBruce Campbell,MD. Support and suggestions from the editorial board have been valuable for feedback and potential changes, and the direction from Editor in Chief Howard Bauchner,MD, and ExecutiveManaging Editor AnnetteFlanaginhavebeencritical for guidanceand improvement. Theentirepublication staff of the JAMANetwork,many ofwhomsupport the journalwithout recognition, are theNetwork’s foundation, and Iwould be amiss if I did not recognize theefforts ofmyoffice staff of SusanLevine, LisaClyman, and Erica Payne. Last but not least, I and the journal are beholden to all the specialty reviewerswhohave selflessly givenof their timeand expertise to critique and improve the submitted manuscripts, as well as to the authors who have chosen to use our journal as their instrument to disseminate their new information. I look forward tocontinuedexcellenceandchangesas the methodsand focusof thepresentationofnew informationmature, and Ihaveappreciatedbeinggiven theopportunity to assist with this task for the past 10 years.With bestwishes to all for continued success and good health.