cssi/SciSciGPT-SciSciNet huggingface dataset:
Elasticity and geometry: a computational model of the Heineke-Mikulicz strictureplasty

Crohn’s disease is a challenging inflammatory process with a propensity for focal gastro-intestinal tract inflammation and stricture. Surgically, Crohn’s is often treated with resection. However, a subtype of diffuse disease with multiple strictures is treated by strictureplasty procedures in hope of avoiding short-gut syndrome. Prior work by Pocivavsek et al. defined the geometry of a Heineke–Mikulicz strictureplasty. Here, we bring this analysis one step closer to clinical and biological relevance by calculating the mechanical stresses and strains that the strictureplasty deformation generates on a model intestinal wall. The small bowel is simulated as a linearly elastic isotropic deformable cylindrical shell using finite element modeling. Data show a divergence in elastic response between the anti-mesenteric and mesenteric halves. The anti-mesenteric surface shows a bending dominated elastic response that correlates with the prior purely geometric analysis. However, the mesenteric half is not a neutral bystander during strictureplasty formation, as geometric arguments predict. Strong in-plane stretching strains develop in a rim around the image of the transverse closure, which may impact local perfusion and serve as sites of disease recurrence. Lastly, nearly all the deformation energy is stored in the central vertex stitch, placing this part at highest risk of dehiscence. This study enhances our understanding of mechanical response in complex nonlinear cylindrical geometries like the surgically manipulated intestinal tract. The developed framework serves as a platform for future addition of more complex clinically relevant parameters to our model, including real tissue properties, anisotropy, blood supply modeling, and patient deriver anatomic factors.
The effect of denervation on leukocyte function in soft tissue infection.

Abstract Background: The present study was undertaken to investigate the effect of denervation on leukocyte function in soft-tissue infection in an isolated in vivo ovine flap model. Methods: Fifteen adult ewes were divided into three groups. An island pedicle flap was raised on the right buttock. In group I (no denervation), the cutaneous nerve remained intact, whereas in group II (acute denervation) the nerve was divided acutely. In group III (prolonged denervation) the nerve was divided 7 days before flap elevation. All flaps received intradermal inoculation of 10 7 Staphylococcus aureus , and the animals were observed for 96 hours. Results: In both groups II and III, the leukocyte chemiluminescence and chemotaxis were significantly decreased when compared with group I. Furthermore, there was profound impairment of leukocyte functions in group III compared with group II. Group III also had significantly higher bacterial counts, larger septic foci, lower viable leukocyte ratios, and decreased bacterial killing compared with group I. Conclusions: Denervation, particularly over a period of time, results in increased bacterial growth of soft-tissue septic foci. This appears to be due to decreased leukocyte function resulting in diminished bacterial killing. (Surgery 1999; 126:933-8.)
Origin of sex

The competitive advantage of sex consists in being able to use redundancy to recover lost genetic information while minimizing the cost of redundancy. We show that the major selective forces acting early in evolution lead to RNA protocells in which each protocell contains one genome, since this maximizes the growth rate. However, damages to the RNA which block replication and failure of segregation make it advantageous to fuse periodically with another protocell to restore reproductive ability. This early, simple form of genetic recovery is similar to that occurring in extant segmented single stranded RNA viruses. As duplex DNA became the predominant form of the genetic material, the mechanism of genetic recovery evolved into the more complex process of recombinational repair, found today in a range of species. We thus conclude that sexual reproduction arose early in the evolution of life and has had a continuous evolutionary history. We cite reasons to reject arguments for gaps in the evolutionary sequence of sexual reproduction based on the presumed absence of sex in the cyanobacteria. Concerning the maintenance of the sexual cycle among current organisms, we take care to distinguish between the recombinational and outbreeding aspects of the sexual cycle. We argue that recombination, whether it be in outbreeding organisms, self-fertilizing organisms or automictic parthenogens, is maintained by the advantages of recombinational repair. We also discuss the role of DNA repair in maintaining the outbreeding aspects of the sexual cycle.
Inhibition of Neuronal Apoptosis by a Metalloporphyrin Superoxide Dismutase Mimic

The objective of this study was to determine whether free radicals play a pathogenic role in neuronal apoptosis. The ability of Mn(III) tetrakis(benzoic acid) porphyrin (MnTBAP), a superoxide dismutase mimic, to inhibit staurosporine-induced neuronal apoptosis was tested in mixed cerebrocortical cultures. Staurosporine produced concentration-dependent cell death that was markedly inhibited by MnTBAP. Immunocytochemical analyses of cultures for neuron- and astrocyte-specific markers revealed that high concentrations of staurosporine induced the death of both neurons and astrocytes; both cell types were protected by MnTBAP. A less active congener of MnTBAP failed to protect cells against staurosporine-induced apoptosis. MnTBAP also protected cortical cultures against ceramide-induced apoptosis. These results support a role for oxidative stress in neuronal apoptosis.
Fc Receptor–Mediated Antibody Regulation of T Cell Immunity against Intracellular Pathogens

Immunity to intracellular microbial pathogens, including Chlamydia species, is controlled primarily by cell-mediated effector mechanisms, yet, the absence of antibodies results in inefficient microbial clearance. We investigated the hypothesis that certain Fc receptor functions promote the rapid induction of elevated T helper type 1 (Th1) response, which effectively clears chlamydiae. FcR(-/-) mice exhibited a delayed and reduced frequency of Chlamydia-specific Th1 cells, compared to FcR(+/+) mice. In vitro, antichlamydial antibodies increased the rate of Th1 activation by FcR(+/+) but not FcR(-/-) antigen-presenting cells. FcR(-/-) dendritic cells and the T cell-associated IgG2A and IgA mediate enhanced Th1 activation by antibodies. Immunization with chlamydia-antibody complexes induced elevated and protective Th1 response. These results provide a mechanistic basis for requiring both T cell and humoral immune responses in protective immunity and vaccine evaluation. Findings offer a paradigm in host defense wherein different effector components function indirectly to maximize the principal effector mechanism.
MiR-122 decreases HCV entry into hepatocytes through binding to the 3' UTR of OCLN mRNA

Background & Aims Analysis in silico suggests that occludin (OCLN), a key receptor for HCV, is a candidate target of miR-122; the most abundant hepatic micro RNA. We aimed to determine if miR-122 can decrease HCV entry through binding to the 3′ UTR of OCLN mRNA. Design Huh7.5 cells were cotransfected with luciferase construct containing 3′ UTR of OCLN (pLuc-OCLN) and with selected miRNAs (0–50 nM) and luciferase activity was measured. Huh7.5 cells were also infected by viral particles containing lenti-miR122 genome or control virus. After 48 h, the cells were infected with HCV pseudo-particles (HCVpp) and VSV pseudo-particles (VSVpp). After 72 h of infection, luciferase activity was measured and HCVpp activity was normalized to VSVpp activity. Results miR-122 binds to the 3′-UTR of OCLN and down-regulates its expression; cotransfection of miR-122 mimic with pLuc-OCLN resulted in a significant decrease in luciferase activity [by 55% (P < 0.01)], while a non-specific miRNA and a mutant miR-122 did not have any effect. miR-122 mimic significantly down-regulated [by 80% (P < 0.01)] OCLN protein in Huh7.5 cells. Accordingly, patients with chronic hepatitis C and higher levels of hepatic miR-122 have lower hepatic expression of OCLN. Immuno-fluorescence imaging showed a decrease in colocalization of OCLN and CLDN following miR-122 over-expression in HCV infected cells. Huh7.5 cells transiently expressing Lenti-miR122 system showed 42% (P < 0.01) decrease in HCV entry. Conclusion This study uncovers a novel antiviral effect of miR-122 on human liver cells and shows that over-expression of miR-122 can decrease HCV entry into hepatocytes through down-regulation of OCLN.
Inverse compton scattering of cosmic ray electrons

Inverse Compton scattering of cosmic ray electrons considered in isotropic thermal radiation field with arbitrary energy
Concentrations and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in aquatic bird eggs from San Francisco Bay, CA 2000-2003

Concentrations of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in 169 avian eggs. We analyzed randomly collected eggs of two species of piscivorous birds: Caspian tern (Sterna caspia) (n=78) and Forster's tern (Sterna forsteri) (n=76). We also analyzed fail-to-hatch eggs from two species protected under the Federal Endangered Species Act of 1973, that breed in the San Francisco Bay region: the piscivorous California Least tern (Sterna antillarum brownii) (n=11) and the omnivorous California Clapper rail (Rallus longirostris obsoletus) (n=4). San Francisco Bay eggs were collected annually for four years (2000-2003), and additional 20 eggs were collected and analyzed from Gray's Harbor, Washington in 2001. Geometric mean PBDE concentrations did not significantly differ in the three tern species, but concentrations in eggs from the fail to hatch California Clapper rail eggs were significantly lower than those found in the randomly collected tern eggs. Median concentrations of SigmaPBDEs in Caspian tern eggs for 2000-2003 were 2410, 4730, 3720 and 2880 ng/g lipid weight (lw), respectively, in Forster's terns 1820, 4380, 5460 and 3600 ng/g lw, respectively, and in California Least terns for 2001 and 2002 were 5060 and 5170 ng/g lw, respectively. In contrast, median SigmaPBDEs concentration in California Clapper rail eggs for 2001 was 379 ng/g lw. Five PBDEs were the major congeners found and decreased in the order BDE-47, -99, -100, -153, and -154. BDE-32, -28, -71, -66, -85, -183 were less prevalent, minor congeners, as was BDE-209, which was measured in a subset of samples. PBDE concentrations in bird eggs from San Francisco Bay were site related. There was no significant difference in PBDE concentrations in Caspian tern eggs from San Francisco Bay and Gray's Harbor, WA. Average PBDE concentrations in eggs did not significantly increase over the period 2000-2003.
Novel therapies in colon cancer

The treatment of metastatic colorectal cancer is currently in transition. The recent advances in treatment provided by bevacizumab and cetuximab have focused research on the development of targeted therapy. This review summarizes the current direction of clinical research and focuses on targeted therapies that are undergoing preclinical and early clinical investigations.
Evidence for exogenous substrate phosphorylation and dimer formation by the activated 190 kDa insulin proreceptor in vitro

The insulin receptor is synthesized as a single chain, 190 kDa glycoprotein precursor, which undergoes proteolytic cleavage, carbohydrate processing, and fatty acylation to generate the mature receptor on the plasma membrane. The relationship of these post-translational modifications to the acquisition of receptor function, i.e. ligand binding and phosphokinase activity, is not fully understood. Therefore, the 190 kDa proreceptor and mature receptor kinase activities were separately examined in vitro, and their phosphorylation properties compared. The solubilized receptor precursor from IM-9 lymphocytes was purified by sequential lectin chromatography and, following site specific anti-receptor antibody immunoprecipitation, phosphokinase studies performed. The isolated proreceptor was activated by insulin and phosphorylated exogenous substrate alpha-casein, as similarly observed for the mature receptor. Structurally, the phosphorylated proreceptor was identified as a 360 kDa homodimer under non-reducing condition.
Spin torque devices in embedded memory: model studies and design space exploration

Ever larger on-die memory arrays for future processors in CMOS logic technology drives the need for dense and scalable embedded memory alternatives beyond SRAM and eDRAM. Recent advances in non-volatile STT-RAM technology, which stores data by the spin orientation of a soft ferromagnetic material and shows current induced switching, have created interest for its use as embedded memory [1-3]. When a spin-polarized current passes through a mono-domain ferromagnet, it attempts to polarize the current in its preferred direction of magnetic moment. As the ferromagnet absorbs some of the angular momentum of the electrons, it creates a torque that causes a flip in the direction of magnetization in the ferromagnet. This is used in magnetic tunneling junction (MTJ) based spin torque transfer (STT) RAM cells where a thin insulator (MgO) is sandwiched between a fixed ferromagnetic layer (polarizer) and the free layer (storage node). This can be integrated in the metal stack (Fig. 1) and hence provide high memory density. Depending on the direction of the current flow (perpendicular to these layers in our study), the magnetization of the free layer is switched to a parallel (P: low resistance state) or anti-parallel (AP: high resistance state) state. The minimum size cell (mincell) contains an access transistor (Tx) of width 2F (WTX=2F, F: half-pitch of the process node) and a planar storage node of dimensions 2FxF. The area of the mincell is 3Fx2F=6F2. In this paper, we examine the design space for key magnetic material properties and access transistor needed for embedded on-die memory with adequate scalability, density, read/write performance and robustness against various intrinsic variabilities and disturbances. New models and simulation methodologies, calibrated to existing measurements [1], for read, write and disturbance mechanisms are developed. Different storage node structures and materials are evaluated to reveal the most promising scaling options.
Abstract A16: External Qi of Yan Xin Qigong induces apoptosis in estrogen-independent breast cancer cells through inhibition of the Akt/NF-κB pathway

Abstracts: Frontiers in Cancer Prevention Research 2008 A16 The concept External Qi of Qigong refers to the technology and ability of the “Qi deployment” therapy and health preservation in traditional Chinese medicine (TCM). External Qi therapy of TCM has long been one of the medical practices and under the management of the health authorities in China. Studies have shown substantial beneficial effects of Yan Xin Qigong (YXQ) that originated from TCM on disease management, weight control, and optimizing caloric intake and diet habit. The external Qi of Yan Xin Qigong (YXQ-EQ) has previously been shown to have potent antioxidative properties. In the present study we have investigated the effect of YXQ-EQ on the Akt/NF-κB signaling pathway that is crucial for tumor growth and progression in estrogen-independent breast cancer MDA-MB-231 cells. YXQ-EQ significantly inhibited constitutive and EGF-stimulated Akt phosphorylation. Furthermore, YXQ-EQ substantially inhibited constitutive NF-κB activity and downregulated the expression of NF-κB target genes Bcl-2, Bcl-xL, XIAP and survivin. YXQ-EQ treatment caused a dramatic reduction in the viability of MDA-MB-231 cells, accompanied by DNA fragmentation, cleavage of PARP, and activation of caspase-3 and caspase-9. These findings suggest that YXQ-EQ might induce apoptosis in MDA-MB-231 cells through inactivation of Akt/NF-κB signaling. YXQ-EQ could potentially be a novel approach for breast cancer prevention and therapy. Citation Information: Cancer Prev Res 2008;1(7 Suppl):A16.
Prospective, randomized comparison of conventional and high dose loading regimens of amiodarone in the treatment of ventricular tachycardia

Abstract Objectives. The purpose of this prospective randomized study was to compare the electrophysiologic effects of conventional and high dose loading regimens of amiodarone in patients with sustained ventricular tachycardia. Background. Uncontrolled studies in which patients have been treated with an oral loading dose of 2 to 4 g/day of amiodarone have suggested that, compared with a conventional loading dose, this dosing regimen results in more rapid control of spontaneous ventricular tachycardia and ventricular tachycardia induced by programmed stimulation. Methods. Patients in whom sustained monomorphic ventricular tachycardia was inducible by programmed stimulation and who were refractory to class I antiarrhythmic medications were randomly assigned to receive either a conventional (n = 15) or a high (n = 17) loading dose of amiodarone. The conventional dose consisted of 600 mg twice a day for 10 days. The high dose regimen consisted of 50 mg/kg body weight per day on days 1 to 3, 30 mg/kg per day on days 4 and 5 and 600 mg twice a day on days 6 to 10. An electrophysiologic test was performed in the baseline state and after 3 and 10 days of therapy. An adequate response to amiodarone was defined as the inability to induce ventricular tachycardia or the ability to induce only relatively slow (cycle length 5 ≥ 350 ms) hemodynamically stable ventricular tachycardia. Results. After 3 days of therapy, 2 of 14 patients who received the conventional loading dose and 6 of 15 patients who received the high dose loading regimen had an adequate response to amiodarone (p = 0.08). After 10 days of therapy, four patients in each group had an adequate response to amiodarone (p = NS). Three patients who received the high dose and one patient who received the conventional dose of amiodarone had an adequate response after 3 days of therapy but not after 10 days of therapy. There were significant increases in the sinus cycle length, atrioventricular block cycle length, ventricular effective refractory period and ventricular tachycardia cycle length after 3 and 10 days of therapy compared with baseline values regardless of the dosing regimen. The extent of the effects of amiodarone on these variables after 3 and 10 days of therapy was similar with both dosing regimens. Conclusions. The therapeutic and electrophysiologic effects of conventional and high dose loading regimens of amiodarone do not differ significantly after 3 or 10 days of therapy. High oral loading doses of amiodarone do not offer any significant clinical advantage over a conventional loading dose of amiodarone for controlling ventricular tachycardia induced by programmed stimulation.
Pressure dependence of self-diffusion in the NaAlO2-SiO2 system: Compositional effects and mechanisms

Molecular Dynamics (MD) simulations were used to study the relationship between structure and transport properties in five liquids (NaAlO2 ,N a 2Al2SiO6, NaAlSiO4, NaAlSi2O6, and NaAlSi3O8) in the system NaAlO2-NaAlSi3O8 at temperatures ranging from 4000 to 6000 K and pressures from 0 to 55 GPa. Seventy simulations were carried out in the microcanonical ensemble using a simple pair-wise additive potential with Coulombic interaction and Born-Mayer repulsion. Detailed study of the coordination of O and network forming cations provides a master set of coordination environment or speciation curves. These master curves were applicable to all compositions and temperatures and were most explicit when compression (Vr/V; where Vr is the molar volume at a reference pressure) was used as the independent variable. The universality implied that coordination environments for network atoms O, Al, and Si depend weakly upon Si/Al, T/O, or Na/T atomic ratios for the compositions studied. Self-diffusion coefficients, computed from analysis of mean-square displacements, were used to evaluate the activation enthalpy (Ha 5 Ea 1 PVa) for self-diffusion for each species. The activation energy ( Ea) for Na was independent of composition, whereas Ea for O, Si, and Al increased as Si/Al increased. Activation volume (Va) at pressure , 15 GPa was positive for Na and negative for O, Si, and Al and decreased with increasing Si/Al for all species. An extension of the Adam-Gibbs-DiMarzio configurational entropy theory taking explicit account of [2] O and [3] O mixing explained both the variation of the pressure-derivative of the shear viscosity as a function of composition and the disappearance of ‘‘anomalous’’ viscosity behavior at P .; 25 GPa for all compositions in the system NaAlO2-NaAlSi3O8.
Searching for the melano-miRs: MiR-214 drives melanoma metastasis

Since the beginning of micro‐RNA (miR) research, several attempts have been made to identify the ‘melano‐miRs’, which are involved in melanoma progression. Indeed, a small number of miRs have been identified to regulate some genes involved in melanogenesis. However, the miRs that control the pathway to the malignant phenotype are yet undescribed. In this issue of the EMBO Journal , Penna et al (2011) demonstrate that miR‐214 is overexpressed in metastatic melanoma cell lines and tumour specimens. miR‐214 regulates the expression of two transcription factors AP‐2γ (directly) and AP‐2α (indirectly). These transcription factors, particularly AP‐2α, have been previously shown to play major roles in melanoma metastasis via regulation of genes involved in extravasation, invasion and angiogenesis. As such, this study has identified miR‐214 as a driver of melanoma metastasis.
Spatial assessment of conjunctive water harvesting potential in watershed systems

Water harvesting can be used to minimize water loss and to augment water supplies in watershed systems. This effort is increasingly being recognized as critical in regions experiencing urbanization and facing uneven water supplies. Water harvesting requires a careful assessment of geographic locations in a watershed and evaluation of surface and groundwater hydrology. In this paper, we develop a spatially explicit method to evaluate costs of harvesting and potential benefits in water harvesting in the Taunton River Watershed in Eastern Massachusetts, USA. A spatial analysis is used to assess surface storage and groundwater recharge potentials in developed and undeveloped regions of the watershed. Distributed parameters used in the analysis include runoff coefficients, land use, soil properties, precipitation, aquifer, and land price. Prioritization maps were developed to characterize conjunctive harvesting potential that is based on benefits and costs. The results demonstrate that a spatially variable harvesting strategy can be used to minimize runoff loss and to augment water supplies. The potential harvest areas were clustered in specific locations that satisfy feasibility and economic criteria. In some subwatersheds, potential harvest locations were dispersed. A spatially variable approach that incorporates economic criteria to hydrologic assessment can be used to enhance efficiency related to water harvest and supply management. Given the increasing demand for clean water, a distributed and conjunctive harvesting strategy could be effective in several urbanizing watersheds. The model has potential for further extension into complex situations of biophysical and socioeconomic conditions at watershed level.
Preliminary evidence that estradiol moderates genetic influences on disordered eating attitudes and behaviors during puberty

Background. Puberty moderates genetic influences on disordered eating attitudes and behaviors, with little genetic influence before puberty but large (o50 %) genetic effects during and after puberty. To date, however, nothing is known about the mechanisms that underlie these effects. Estradiol is a particularly promising candidate, as estrogens become elevated at puberty and regulate gene transcription within neurotransmitter systems important for eatingrelated phenotypes. The aim of this pilot study was to examine whether estradiol levels moderate genetic influences on disordered eating during puberty. Method. Participants included 198 female twins (ages 10–15 years) from the Michigan State University Twin Registry. Disordered eating attitudes and behaviors were assessed with the total score, weight preoccupation, body dissatisfaction and binge eating/compensatory behavior subscales of the Minnesota Eating Behavior Survey (MEBS). Afternoon saliva samples were assayed for estradiol levels. Moderation of genetic effects was examined by comparing twin correlations in low versus high estradiol groups. Results. In the low estradiol group, monozygotic (MZ) and dizygotic (DZ) twin correlations for all MEBS scales were similar, suggesting little genetic influence. In the high estradiol group, the MZ twin correlation was more than double the DZ twin correlation, indicating the presence of genetic effects. Findings could not be accounted for by age, body mass index or the physical changes of puberty. Conclusions. Estradiol may be one important moderator of genetic effects on disordered eating during puberty. Larger twin studies are needed to replicate this pilot work and quantify the extent of genetic moderation. Received 31 July 2009 ; Revised 12 November 2009 ; Accepted 13 November 2009 ; First published online 11 January 2010
Single-molecule force spectroscopy of DNA-based reversible polymer bridges: Surface robustness and homogeneity

Single-molecule force spectroscopy, as implemented in an atomic force microscope, provides a rarely used method by which to monitor dynamic processes that occur near surfaces. Here, a methodology is presented and characterized that facilitates the study of polymer bridging across nanometer-sized gaps. The model system employed is that of DNA-based reversible polymers, and an automated procedure is introduced that allows the AFM tip-surface contact point to be automatically determined, and the distance d between opposing surfaces to be actively controlled. Using this methodology, the importance of several experimental parameters was systematically studied, e.g. the frequency of repeated tip/surface contacts, the area of the substrate surface sampled by the AFM, and the use of multiple AFM tips and substrates. Experiments revealed the surfaces to be robust throughout pulling experiments, so that multiple touches and pulls could be carried out on a single spot with no measurable affect on the results. Differences in observed bridging probabilities were observed, both on different spots on the same surface and, more dramatically, from one day to another. Data normalization via a reference measurement allows data from multiple days to be directly compared.
Design and Assessment of a Depth-Fused Multi-Focal-Plane Display Prototype

Depth-fused multi-focal-plane display was proposed to create a fixed-viewpoint volumetric display capable of rendering correct or nearly-correct focus cues in a stereoscopic display through a small number of discretely placed focal planes. It may effectively address the negative effects of conventional stereoscopic displays on depth perception accuracy and visual fatigue due to the lack of focus cues. In this paper, we presented the design and assessment of a novel depth-fused six-focal plane display prototype, capable of rendering nearly-accurate focus cues for a depth range of 3 diopters with high image quality at flicker-free speed. The optical system design, prototype implementation and demonstration, and experimental assessment of the prototype were discussed in detail.
Central Nervous System and Renal Vasculitis Associated With Primary Varicella Infection in a Child

A 7-year-old girl with primary varicella presented with encephalopathy and focal neurologic deficits 10 days after her first skin lesions appeared. She was discovered to have bilateral wedge-shaped renal infarctions, and ischemic lesions in the conus medullaris, cerebral cortex, and deep gray matter consistent with a medium and large vessel arteritis on magnetic resonance imaging. This complication has never before been reported in an immunocompetent child with primary varicella infection, and it represents a rare but serious complication of childhood chickenpox.
Kinetic and fluid Langmuir wave nonlinearities driven by stimulated Raman scattering in a diffraction limited single-hot-spot

A diffraction limited focal spot is used to create a single speckle in a preformed plasma. The single speckle, or hot spot, is the simplest irreducible element for studying laser plasma interactions. Using the single hot spot configuration, the nonlinear behavior of SRS driven Langmuir waves has been investigated in both a fluid dominated and a kinetic regime. A transition between the two regimes has been observed as a function of kλD where k is the Langmuir wave-number and λD is the Debye length.
Phase diagram of imprinted copolymers

Recently, a model for the preparation of “protein-like" heteropolymers with a unique and stable ground state has been proposed and examined computationally. Formally, this model is similar to another recently proposed and computationally examined model of the evolutionary design of protein-like heteropolymers. Using mean field replica theory, we find, in addition to the freezing transition of random chains, a transition to the target “native" state. The stability of this state is shown to be greater than that of the ground state of random chains. The results derived here should at least qualitatively be applicable to known biopolymers, which are conjectured to be in vivo “designed" by evolution. Furthermore, we present a crude prescription for a laboratory procedure in which chains can be synthesized in vitro.
Language Use in Imagined Dialogue and Narrative Disclosures of Trauma.

Support exists in many populations for the use of written disclosure to express thoughts and emotions about a traumatic experience. The present study examined language use in a variation of the writing task modified to include an imagined dialogue with another person. We hypothesized that this method would increase cognitive, affective, and present-tense word use, all of which are linked with beneficial outcomes from writing. We randomly assigned 169 college students to write in one of three conditions: trauma narrative, trauma dialogue, or control writing. Results suggested that writing about traumatic experiences in the form of a dialogue promotes greater present-oriented, affective experiencing and cognitive processing than does writing in the form of a narrative.
Efferent Protection from Acoustic Injury Is Mediated via α9 Nicotinic Acetylcholine Receptors on Outer Hair Cells

Exposure to intense sound can damage the mechanosensors of the inner ear and their afferent innervation. These neurosensory elements are innervated by a sound-activated feedback pathway, the olivocochlear efferent system. One major component of this system is cholinergic, and known cholinergic effects are mediated by the alpha9/alpha10 nicotinic acetylcholine receptor (nAChR) complex. Here, we show that overexpression of alpha9 nAChR in the outer hair cells of bacterial artificial chromosome transgenic mice significantly reduces acoustic injury from exposures causing either temporary or permanent damage, without changing pre-exposure cochlear sensitivity to low- or moderate-level sound. These data demonstrate that efferent protection is mediated via the alpha9 nAChR in the outer hair cells and provide direct evidence for a protective role, in vivo, of a member of the nAChR family.
FOXP3 Controls an miR-146/NF-κB Negative Feedback Loop That Inhibits Apoptosis in Breast Cancer Cells.

FOXP3 functions not only as the master regulator in regulatory T cells but also as an X-linked tumor suppressor. The tumor suppressive activity of FOXP3 has been observed in tumor initiation, but its role during tumor progression remains controversial. Moreover, the mechanism of FOXP3-mediated tumor suppressive activity remains largely unknown. Using chromatin immunoprecipitation sequencing, we identified a series of potential FOXP3-targeted microRNAs (miRs) in MCF7 cells. Notably, FOXP3 significantly induced the expression of miR-146a/b. In vitro, FOXP3-induced miR-146a/b prevented tumor cell proliferation and enhanced apoptosis. Functional analyses in vitro and in vivo revealed that FOXP3-induced miR-146a/b negatively regulate NF-κB activation by inhibiting the expression of IRAK1 and TRAF6. In chromatin immunoprecipitation assays, FOXP3 directly bound the promoter region of miR-146a but not of miR-146b, and FOXP3 interacted directly with NF-κB p65 to regulate an miR-146-NF-κB negative feedback regulation loop in normal breast epithelial and tumor cells, as demonstrated with luciferase reporter assays. Although FOXP3 significantly inhibited breast tumor growth and migration in vitro and metastasis in vivo, FOXP3-induced miR-146a/b contributed only to the inhibition of breast tumor growth. These data suggest that miR-146a/b contribute to FOXP3-mediated tumor suppression during tumor growth by triggering apoptosis. The identification of a FOXP3-miR-146-NF-κB axis provides an underlying mechanism for disruption of miR-146 family member expression and constitutive NF-κB activation in breast cancer cells. Linking the tumor suppressor function of FOXP3 to NF-κB activation reveals a potential therapeutic approach for cancers with FOXP3 defects.
The Mediating Role of Perceived Burdensomeness in Relations Between Domains of Cognitive Functioning and Indicators of Suicide Risk.

OBJECTIVES: Psychiatric inpatients are at elevated risk for suicide, but there are mixed findings regarding cognitive functioning (i.e., executive functioning and problem-solving abilities) and suicide risk in this population. We hypothesized that a mediating variable (i.e., perceived burdensomeness) may explain these mixed findings. METHOD: This hypothesis was tested in a sample of psychiatric inpatients admitted for suicide-related concerns (N = 110; 58.18% female, Mage = 36.45) using a nonparametric bootstrapping procedure. RESULTS: Perceived burdensomeness did not act as a mediator between any domain of cognitive functioning and current suicide ideation nor presence of recent suicide attempts. However, perceived burdensomeness was the strongest predictor of suicide ideation and mediated the relation between objective problem-solving skill and suicide risk (a weighted variable comprising current ideation and previous attempts). CONCLUSIONS: Perceived burdensomeness may be associated with elevated suicide ideation, suggesting that perceived burdensomeness should be assessed to inform suicide risk decisions. Language: en
Mechanisms of Protein Evolution

How does nature generate new enzyme functions? Several possible mechanisms for the development of novel function have been observed: (i) dual-functionality proteins (“moonlighting proteins” and catalytic promiscuity); (ii) gene duplication; (iii) horizontal gene transfer; and (iv) circular permutation of structure. There are three dominant principles of enzyme evolution: Retained substrate specificity (binding), changed chemistry: A new enzyme evolves to supply substrate from an available precursor by evolution of enzyme using the substrate. The underlying hypothesis states that metabolic pathways evolve backwards: A B C, EA B is new, EB C is old enzyme; Retained chemistry, changed substrate specificity (binding): Nature selects protein from a pool of enzymes whose mechanism provide a partial reaction or stabilization strategy for intermediates or transition states. Evolution decreases the proficiency of the reaction catalyzed by the progenitor. The underlying hypothesis states that chemical mechanism dominance starts with a low level of promiscuous activity and that once evolved it is beneficial for nature to utilize it over and over again. Active-site architecture retained: In this case, the active site is able to support alternative reactions with shared functional groups in a different mechanistic or metabolic context. The study of α/β-barrel proteins, also termed (αβ)8-barrel or TIM barrel proteins, is important because (i) the structure is found in 10% of all known structures, 68% of them enzymes; (ii) residues responsible for stability are separate from residues responsible for function; and (iii) the general scaffold catalyzes several classes of catalysis: oxidoreductases, hydrolases, lyases, and isomerases. Originally published in: Biocatalysis. Andreas Sebastian Bommarius and Bettina R. Riebel. Copyright © 2004 Wiley-VCH Verlag GmbH & Co. KGaA Weinheim Print ISBN: 3-527-30344-1 The sections in this article are Introduction Congruence of Sequence, Function, Structure, and Mechanism Search Characteristics for Relatedness in Proteins Classification of Relatedness of Proteins: the -log Family Classification into Protein Families Dominance of Different Mechanisms Evolution of New Function in Nature Dual-Functionality Proteins Moonlighting Proteins Catalytic Promiscuity Gene Duplication Horizontal Gene Transfer (HGT) Circular Permutation α/βJ-Barrel Proteins as a Model for the Investigation of Evolution Why Study α/β-Barrel Proteins? Example of Gene Duplication: Mandelate and α-Ketoadipate Pathways Description of Function Exchange of Function in the Aromatic Biosynthesis Pathways: Trp and His Pathways Keywords: biocatalytic function; relatedness of proteins; protein families; gene duplication; horizontal gene transfer (HGT); α/β-barrel proteins; mandelate; α-ketoadipate; Trp
The Academic Interests of College Women: A Factorial Study

The extent to which college programs meet the needs and goals of women students has not been established. In this study, a sample of students and alumnae of the College of Home Economics, Iowa State University, responded to a set of attitude scales concerning their reactions to courses in their core curriculum. Factor analysis of the person-course interactions revealed 6 factors which were tentatively defined in terms of the courses loading most heavily on each. Implications for improved educational planning of women are discussed.
Bolus transit patterns in healthy subjects: a study using simultaneous impedance monitoring, videoesophagram, and esophageal manometry.

Impedance monitoring (Imp) measures bolus transit. Combining Imp with manometry (EM) allows the effect of contractile patterns on transit to be assessed. The objective of this study is to identify ...
Breast Cancer Trends Among Black and White Women in the United States

Purpose Overall US breast cancer mortality rates are higher among black women than white women, and the disparity is widening. To investigate this disparity, we examined incidence data and changes in mortality trends according to age, year of death (calendar period), and date of birth (birth cohort). Calendar period mortality trends reflect the effects of new medical interventions, whereas birth cohort mortality trends reflect alterations in risk factors. Patients and Methods Incidence data were obtained from the Connecticut and National Cancer Institute Surveillance, Epidemiology, and End Results registries and mortality data were obtained from the National Center for Health Statistics. Changes in age, period, and cohort mortality trends were analyzed with Poisson regression. Results For both races, breast cancer incidence rates for localized and regional disease diverged in the late 1970s. Almost concurrently, overall mortality rates diverged among blacks and whites. For both races, mortality increases with age, but blacks have higher mortality at age younger than 57. The calendar period curves revealed declining mortality for whites over the entire study period. For blacks, calendar period mortality declined until the late 1970s, and then sharply increased. After 1994, calendar period mortality declined for both. For women born between 1872 and 1950, trends in mortality were similar for blacks and whites. For women born after 1950, mortality decreased more rapidly for blacks. Conclusion The widening racial disparity in breast cancer mortality seems attributable to calendar period rather than birth cohort effects. Thus, differences in response or access to newer medical interventions may largely account for these trends. J Clin Oncol 23:7836-7841.
A fuzzy set theory based control of a phase-controlled converter DC machine drive

A description is presented of the application of fuzzy logic in a speed control system that uses a phase-controlled bridge converter and a separately excited DC machine. The fuzzy control is used to linearize the transfer characteristics of the converter in the discontinuous conduction mode occurring at light load and/or high speed. The fuzzy control is then extended to the current and speed control loops replacing the conventional proportional-integral (PI) control method. The compensation and control algorithms have been developed in detail and verified by digital simulation of a drive system. The simulation study indicates the superiority of fuzzy control over the conventional control methods. Fuzzy logic seems to have a lot of promise in the application of power electronics. >
Locating events with a sparse network of regional arrays

Abstract An automated procedure for locating regional seismic events with a network including arrays and single element seismometers is described. The method incorporates backazimuth estimates, arrival-time data, and associated uncertainties into a least-squares-inverse location algorithm. The formulation is essentially that of Jordan and Sverdrup extended to incorporate azimuth data. This technique allows the use of both a priori and a posteriori information about data uncertainties to compute confidence ellipsoids for location estimates. This is important for obtaining realistic confidence ellipsoids for solutions based on few data. It also permits a refinement of the confidence ellipsoid calculations as experience accumulates for events in a particular area. Small arrays like NORESS in Norway provide accurate estimates for the backazimuth of regional phases. These azimuth data provide a strong constraint on the location of events detected by a small number of stations. The strength of the constraint depends on the geometry, and in some situations azimuth data are as important as arrival-time data. Synthetic examples illustrating this are given for a network including two arrays. Actual data from the NORESS array in southern Norway and the FINESA array near Helsinki, Finland, are presented to demonstrate the use of the location technique. Most of the events studied are mine blasts for which there are highly accurate, independent locations. Comparing one-array and two-array locations and their confidence ellipses with these independent locations provides a preliminary validation of our estimates of the (signal-dependent) a priori arrival-time and azimuth variances, and demonstrates the effectiveness of our location procedure for a sparse network of regional arrays.
Impression Management, Psychology of

Impression management(also called self-presentation involves the processes by which people control how they are perceived by others. People are more motivated to control how others perceived them when they believe that their public images are relevant to the attainment of desired goals, the goals for which their impressions are relevant are valuable, and a discrepancy exists between how they want to be perceived and how other people perceive them. When people are motivated to manage their impressions, the impressions that they try to convey are influenced by the roles that they occupy and the norms in the social context, the values of the individuals whose perceptions are of concern, how they think they are currently perceived, their self-concepts, and their desired and undesired selves. Research on impression management has developed along two distinct paths. One line of research focuses on factors that affect the kinds of impressions people try to convey, and the other line applies self-presentaional perspectives have been applied to the study of other psychological phenomena. Self-presentational perspectives have been applied to the study of topics such as conformity, aggression, prosocial behavior, leadership, negotiation, social influence, gender, stigmatization, close relationships, emotional experience, and mental and physical health.
Control of Salt-Water Intrusion by Recharge Wells

The present investigation involves study of the effect of a battery of recharge wells on control of salt water in coastal confined aquifers. In each investigation, the battery has a specific number of recharge wells equally spaced and located along a line normal to the direction of natural ground-water flow and parallel to the shoreline. The degree of salt-water retardation is defined in the text and determined for 96 cases. The results may be used directly in managing coastal aquifers as illustrated by an example. Various conditions are studied by changing the location of the battery from the coast, the magnitude of well spacing intensities of pumping, and their duration. All wells are assumed to be recharging at the same intensity for the same periods of time in each system. Influencing factors are grouped into dimensionless parameters and results of the solutions lead to the construction of design graphs.
Calculation of complex singular solutions to the 3D incompressible Euler equations

This paper presents numerical computations of complex singular solutions to the 3D incompressible Euler equations. The Euler solutions found here consist of a complex valued velocity fleld u+ that contains all positive wavenumbers; u+ satisfles the usual Euler equations but with complex initial data. The real valued velocity u = u+ + ui (where ui = u+) is an approximate singular solution to the Euler equations under Moore’s approximation. The method for computing singular solutions is an extension of that in Ca∞isch (1993) for axisymmetric ∞ow with swirl, but with several improvements that prevent the extreme magniflcation of round-ofi error which afiected previous computations. This enables the flrst clean analysis of the singular surface in three-dimensional complex space. We flnd singularities in the velocity fleld of the form u+ » » fii1 for fi near 3=2 and u+ » log», where » = 0 denotes the singularity surface. The logarithmic singular surface is related to the double exponential growth of vorticity observed in recent numerical simulations.
Response of Cutaneous A- and C-Fiber Nociceptors in the Monkey to Controlled-Force Stimuli

The goal of this study was to determine the capacity of primary afferent nociceptive fibers (nociceptors) to encode information about noxious mechanical stimuli in primates. Teased-fiber techniques were used to record from 14 A-fiber nociceptors and 18 C-fiber nociceptors that innervated the hairy skin. Stimulus-response functions were examined with an ascending series of force-controlled stimuli. Stimulus-interaction effects were examined with use of a series of paired stimuli in which the interval between the stimulus pairs was varied systematically. Both A-fiber and C-fiber nociceptors exhibited a slowly adapting response to the stepped force stimuli. The response of the A fibers increased monotonically with increasing force, whereas the response of the C fibers reached a plateau at low force levels. The slope of the stimulus-response function for the A fibers was significantly steeper than that for the C fibers, and the total response was greater. The A fibers also provided more discriminative information regarding stimulus intensity. The C fibers demonstrated a significant fatigue in response when the interstimulus interval between the paired stimuli was </=150 s, whereas the A fibers did not demonstrate a significant fatigue until the interstimulus interval was </=30 s. This fatigue in response was not due to changes in tissue compliance. These results suggest that A- and C-fiber nociceptors have different mechanical transduction mechanisms. A-fiber nociceptors exhibit steeper stimulus-response functions and less fatigue than C-fiber nociceptors.