cssi/SciSciGPT-SciSciNet huggingface dataset:
Wingless-type frizzled protein receptor signaling and its putative role in human colon cancer.

We wish to identify new candidate genes involved in the pathogenesis of human colon cancer to better understand the diversity of phenotype presentation that varies from individual to individual. Our working hypothesis is that genetic polymorphism of genes in the Wingless-type (Wnt) frizzled protein receptor pathway is associated with the susceptibility to develop colon cancer. The putative role of the Wnt pathway in sporadic human malignancy of the colon suggests involvement in inherited cancer as well. beta-catenin is the crucial messenger in frizzled receptor signaling, transmitting Wnt-ligand signals such as signals from secreted apoptosis-related proteins to the nucleus. It functions as a genome denunciator by initiating amplification of oncogenes. The net effect of beta-catenin depends on the magnitude of its accumulation in the cytoplasm and, therefore, upon expression profiles of genes in the Wnt pathway. We propose that variations in allelic frequencies of genes involved in the beta-catenin cascade may either promote or impede malignant transformation of the colon. If certain polymorphisms in Wnt signaling through beta-catenin predispose to colon cancer, this might manifest as decreased binding affinity of proteins such as axin or the adenomatous polyposis coli protein to beta-catenin. Association studies are proposed to test the hypothesis, which could serve as an initial step toward understanding the complexity of tumor biology. The clinical rationale in unraveling the genetic susceptibility to cancer lies in identification of a subgroup of individuals who may benefit from beta-catenin targeting agents, which could potentially overcome this genetic instability.
Psyched-up to Suck-up: Self-regulated Cognition, Interpersonal Influence, and Recommendations for Board Appointments in the Corporate Elite

This study reveals how self-regulated cognition in advance of social interaction can resolve the so-called “ingratiator’s dilemma,” which is that the most attractive targets of social influence—tho...
Membrane Association of the PTEN Tumor Suppressor: Molecular Details of the Protein-Membrane Complex from SPR Binding Studies and Neutron Reflection

The structure and function of the PTEN phosphatase is investigated by studying its membrane affinity and localization on in-plane fluid, thermally disordered synthetic membrane models. The membrane association of the protein depends strongly on membrane composition, where phosphatidylserine (PS) and phosphatidylinositol diphosphate (PI(4,5)P2) act pronouncedly synergistic in pulling the enzyme to the membrane surface. The equilibrium dissociation constants for the binding of wild type (wt) PTEN to PS and PI(4,5)P2 were determined to be Kd∼12 µM and 0.4 µM, respectively, and Kd∼50 nM if both lipids are present. Membrane affinities depend critically on membrane fluidity, which suggests multiple binding sites on the protein for PI(4,5)P2. The PTEN mutations C124S and H93R show binding affinities that deviate strongly from those measured for the wt protein. Both mutants bind PS more strongly than wt PTEN. While C124S PTEN has at least the same affinity to PI(4,5)P2 and an increased apparent affinity to PI(3,4,5)P3, due to its lack of catalytic activity, H93R PTEN shows a decreased affinity to PI(4,5)P2 and no synergy in its binding with PS and PI(4,5)P2. Neutron reflection measurements show that the PTEN phosphatase “scoots" along the membrane surface (penetration <5 A) but binds the membrane tightly with its two major domains, the C2 and phosphatase domains, as suggested by the crystal structure. The regulatory C-terminal tail is most likely displaced from the membrane and organized on the far side of the protein, ∼60 A away from the bilayer surface, in a rather compact structure. The combination of binding studies and neutron reflection allows us to distinguish between PTEN mutant proteins and ultimately may identify the structural features required for membrane binding and activation of PTEN.
Bidirectional gene transfer between Aspergillus fumigatus and Aspergillus nidulans

A genomic DNA library was constructed from a pathogenic strain of Aspergillus fumigatus using the cosmid vector pCosAX. Cosmid clones with homologies to the rodA, brlA, fluG, flbA or trpC genes from A. nidulans were isolated from the library. Each A. fumigatus clone was used to complement strain of A. nidulans with a mutation in the homologous gene. A spontaneous white spored strain of A. fumigatus was isolated. The mutation was complemented by transforming the strain with a plasmid containing the wA gene from A. nidulans. The results from these experiments indicate a significant degree of structural and functional homology between genes from the organisms. These findings indicate the potential to exploit the methods and information available from A. nidulans to address questions related to human disease caused by A. fumigatus and the ability to use A. nidulans as a surrogate genetic host for characterizing A. fumigatus gene function.
Median sternotomy for metastatic lung lesions in 131 patients.

Aggressive management of malignant primary tumors and their metastatic manifestations is associated with improved survival outcomes. As investigators continue to focus attention on the ablation or control of pulmonary metastatic foci, surgery is gaining importance in the treatment of metastatic disease to the lungs and, in this context, is adjunctive to other therapeutic modalities. At Roswell Park Memorial Institute (RPMI), median sternotomy is preferred to unilateral or staged bilateral thoracotomies, since the former provides simultaneous access to both hemithoraces, whereas its lower morbidity facilitates the earlier resumption of systemic therapy. The RPMI experience, amassed from 131 patients and using this procedure, is presented and analyzed with respect to patient survival. Cancer 55:1334-1339, 1985.
The effects of altering time delays of coupled pacing during acute atrial fibrillation.

Background Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. Objective The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. Methods In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of ≈20 mmHg). These longer delays were designated CP-L. Results Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and d LVP/ dt , which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O 2 consumption (MVO 2 ) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. Conclusions In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied.
A model for transepithelial ion transport across the isolated retinal pigment epithelium of the frog.

Abstract The contribution of chloride ion movement and sodium and bicarbonate concentrations to the net current across the isolated choroid-retinal pigment epithelium (RPE) of the bullfrog were studied. The presence of a ouabain-sensitive Na + K + -pump on the retinal side was confirmed and complete inhibition of this pump with Na + removal and ouabain treatment abolished nearly all the RPE transepithelial transport and SCC suggesting that all ionic transport was dependent on sodium. It was found that apical to basal (AB) chloride flux accounted for 26±2% (mean± s.e.m. ) of the short circuit (SCC). Results suggest that AB bicarbonate and/or basal apical (BA) hydrogen ion net transport accounts for 38±2% of the SCC while BA sodium is presumably responsible for the remaining 34% of the SCC. Transport was inhibited by apical administration of known chloride inhibitors. Trans-RPE 36 Cl flux measurements indicate that furosemide (10 −4 m ), bumetanide (10 −4 m ) and SITS (10 −3 ) decrease the retinal-choroid flux. Results suggest that net transport of chloride and bicarbonate are independent of each other and additive. It was found that a bicarbonate-free preparation was relatively unaffected by changes in pH (5·5–8·5) indicating that pH has little, if any, effect on sodium or chloride current in this range. A model is presented which is compatible with the various data. It is suggested that along with the apical Na + K + -ATPase pump, there exists an apical Na + Cl − -co-transport system which is driven by the established sodium gradient. Moreover, this pump established sodium gradient is postulated to drive a Na + HCO 3 − -co-transport system tentatively placed on the retinal side of the RPE.
Nature’s Pharmaceuticals: Sanctioned Desires in Alain de Lille’s De planctu Naturae

Alain de Lille’s De planctu Naturae is the most self-contradictory of texts. Yet it is deliberately so and serves to complicate the antonymic relationship between deviance and “natural” desire. Alain effects this “ambiguity and reversibility” of binary oppositions through the medicamen of metaphorical substitution and in the process provides a striking analogue to the pharmako­n that Derrida argues to be the structural principle subtending Plato’s Phaedrus.
Early second trimester prenatal diagnosis of Neu-Laxova syndrome.

Neu-Laxova is a rare, uniformly lethal, autosomal recessive condition with characteristic limb posturing, facial dysmorphic features, and central nervous system abnormalities. Forty-two cases of Neu-Laxova syndrome have been reported, with only four of these diagnosed prenatally. Three of the four cases were diagnosed at or after 32 weeks' gestation. The fourth case was diagnosed at 22 weeks' gestation in a patient who was followed with serial ultrasound studies due to having a prior affected child. At 19 weeks' gestation, we present the earliest reported prenatal diagnosis of Neu-Laxova syndrome in a primigravida with a non-informative family history. Copyright © 2002 John Wiley & Sons, Ltd.
Lessons from The Baby Boon: “Family-Friendly” Policies and the Ethics of Justice and Care

Over the past three decades, feminist activists have promoted a wide range of “family-friendly” policies in workplaces and in the public sector. In The Baby Boon, Elinor Burkett appeals to feminist principles to challenge these efforts. I argue that the debate can be explained through an examination of the ethical stances underlying the differing claims, concluding that to create workplaces and public policies that are both fair and humane, we must bring justice and care into dialogue.
An Analysis of Computer Architectural Factors Contributing to Image Processor Capacity

An Analysis of Computer Architectural Factors Contributing toImage Processor CapacityRobert M. Lougheedand Claron W. SwongerIntelligent Machine Technology DepartmentEnvironmental Research Institute of MichiganAnn Arbor, MichiganA quantitative analysis is provided of how specific architectural features of imageprocessors enhance the over -all algorithmic capacity of the corresponding vision system.Such features are discussed at a more detailed level than common SISD and MISDarchitectural categorizations. Metrics are presented to allow comparisons to be madebetween fundamentally different architectures.IntroductionThe rapidly evolving technology of computer -based image processing is generating a wideassortment of architectural concepts and specific designs. In total, architectures havebeen suggested which display many dimensions of variability, including:
A micro-sized bio-solar cell for self-sustaining power generation

Self-sustainable energy sources are essential for a wide array of wireless applications deployed in remote field locations. Due to their self-assembling and self-repairing properties, “biological solar (bio-solar) cells” are recently gaining attention for those applications. The bio-solar cell can continuously generate electricity from microbial photosynthetic and respiratory activities under day–night cycles. Despite the vast potential and promise of bio-solar cells, they, however, have not yet successfully been translated into commercial applications, as they possess persistent performance limitations and scale-up bottlenecks. Here, we report an entirely self-sustainable and scalable microliter-sized bio-solar cell with significant power enhancement by maximizing solar energy capture, bacterial attachment, and air bubble volume in well-controlled microchambers. The bio-solar cell has a ~300 μL single chamber defined by laser-machined poly(methyl methacrylate) (PMMA) substrates and it uses an air cathode to allow freely available oxygen to act as an electron acceptor. We generated a maximum power density of 0.9 mW m−2 through photosynthetic reactions of cyanobacteria, Synechocystis sp. PCC 6803, which is the highest power density among all micro-sized bio-solar cells.
On the origin of the Z-shaped narrow-line region in the Seyfert galaxy NGC 3516

A kinematic study has been carried out of the line-emitting gas in the Seyfert galaxy NGC 3516. The existence of two curved filaments in the central 2.5 kpc of this galaxy, which give Z-shaped appearance to its NLR. A precessing twin-jet model in which the line-emitting material is entrained by a precessing radio jet and kept ionized by the nuclear ionization field can explain the kinematic data of the brightest emission rather well. If this model is valid, this would make NGC 3516 the least luminous known active galaxy with a precessing jet. An alternative scenario assumes that the curved inner filaments represent gas entrained by a radio jet which is deflected by ram pressure from the rotation interstellar medium of the galaxy.
Effects of Diabetes on the Eye

Hyperglycemia has toxic effects on almost all cells in the body. Ophthalmic complications of hyperglycemia are most profound in cornea and retina. Seventy percent of diabetics suffer from corneal complications, collectively called diabetic keratopathy, which includes include recurrent erosions, delayed wound healing, ulcers, and edema. Confocal microscopy has permitted in vivo imaging of corneal nerves, which are also affected in diabetic subjects. Gene therapies upregulating MNNG HOS transforming gene (cMet) and/or downregulating MMP10 and cathepsin S are potential future therapies for diabetic keratopathy. Diabetic retinopathy (DR) is the most common cause of blindness in people over the age of 50. There is accumulating evidence that DR is an inflammatory disease. The initial events in animal models of DR are increased vascular permeability and leukostasis. This binding of leukocytes to the endothelium results from an increase in intracellular adhesion molecule-1 (ICAM-1) on the retinal capillary endothelium (EC) and expression of CD11/CD18 on the surface of the activated leukocyte. We have observed polymorphonuclear leukocytes (PMNs) at sites of EC vascular dysfunction in diabetic retinas as well as choroid. Anti-inflammatory drugs like etanercept, aspirin, or meloxicam reduce leukostasis and EC death. Future therapies may include repopulation of the acellular capillaries after EC and pericyte death with vascular progenitors made from the patient's own blood cells.
Description of a simultaneous emission-transmission CT system

We are designing an instrument which will perform correlated emission-transmission image acquisition, but which departs from previous systems by incorporating a low-power x-ray tube and generator, rather than a radionuclide source, for the transmission image. The system uses an array of high-purity germanium (HPGe) detectors and detector electronics with energy discrimination circuitry to separate x-rays (at 100 or 120 kVp) from higher energy gamma rays from the 99mTc or 123j radiopharmaceutical injected into the patient. The data acquisition electronics have time constants matching the charge collection time (50 ns) of the HPGe detectors to maximize count-rate capabilities (up to 1 million cps per detector element), while maintaining adequate energy resolution (approximately 10% FWHM). Each detector channel has two energy windows for simultaneous transmission-emission imaging or for dual-energy x-ray studies. A host computer provides system control as well as data acquisition, data correction, tomographic image reconstruction, image display, and data analysis. As a radionuclide imaging system, this instrument will function as a single-slice SPECT scanner with high-count rate capabilities and excellent energy resolution for imaging short-lived radionuclides, improved photopeak discrimination and scatter rejection, and simultaneous imaging of multiple radionuclides. The system also will generate radiographic images in either a tomographic or projection scanning mode, while dual-energy x-ray CT will provide material specific imaging. However, the novel and potentially powerful capabilities of this instrument would derive from its inherent correlation of functional information from SPECT with precise anatomic information from CT or the material-specific morphologic information from dual-energy x-ray CT. The simultaneously acquired radiographic images should relieve the deficiencies of poor statistics and limited spatial resolution commonly associated with SPECT systems. Dual-energy xray CT also can provide an energy-corrected and anatomically-correlated map of attenuation coefficients for more accurate quantitation of emission radionuclide data.
Speckle Spectroscopy - an Application for the Multi-Anode Microchannel Array Detector System

Plans to combine the High Angular Resolution Imager/Spectrometer on the 4-meter Mayall telescope at the Kitt Peak National Observatory and the (256 x 1024)-pixel Multi-Anode Microchannel Array detector system to produce a unique instrument for speckle spectroscopy are described. The pulse-counting detector system will provide distortion-free imaging and will time tag each spatially-resolved photon event with an accuracy of 100 ns. The Imager/Spectrometer will provide a spatial resolution of 0.07 arcsec orthogonal to the plane of dispersion and 0.18 arcsec in the plane of dispersion.
Adenosine deaminase reduces hypoxic and hypercapnic dilatation of rat pial arterioles: evidence for mediation by adenosine.

Abstract Rat pial arteries were observed throguh a closed cranial window durign hypercapnic and hypoxic episodes whilst the cerebral cortex was superfused at 37°C first with articificial cerebrospinal fluid (CSF) and subsequently with adenosine deaminase (ADA, 0.5–2.0 U/ml) in CSF. The results indicate that ADA attenuated hypercapnic and hypoxic dilatatory arteriorlar responses by 64% and 56% respectively. Recovery was obtained by superfusing with ADA-free CSF for 1 h. We conclude that adenosine is involved in hypercapnia- and hypoxia-evoked dilation of pial arteries.
Integrating sensing, task planning and execution

This paper deals with enhancing the level of autonomy in a robotic work cell. With that mission in mind, we present here an integrated framework for the sensing, the planning, and the execution aspects of assembly. In experimental demonstrations of this system on a PUMA 762, we can now throw objects randomly into the work space of the robot and the robot then automatically synthesizes a manipulation plan that includes the operations of sensing and regrasping only when these are deemed necessary for the successful execution of assembly. >
Saccharomyces cerevisiae mutants unresponsive to alpha-factor pheromone: alpha-factor binding and extragenic suppression.

Abstract Mutations in six genes that eliminate responsiveness of Saccharomyces cerevisiae a cells to alpha-factor were examined by assaying the binding of radioactively labeled alpha-factor to determine whether their lack of responsiveness was due to the absence of alpha-factor receptors. The ste2 mutants, known to be defective in the structural gene for the receptor, were found to lack receptors when grown at the restrictive temperature; these mutations probably affect the assembly of active receptors. Mutations in STE12 known to block STE2 mRNA accumulation also resulted in an absence of receptors. Mutations in STE4, 5, 7, and 11 partially reduced the number of binding sites, but this reduction was not sufficient to explain the loss of responsiveness; the products of these genes appear to affect postreceptor steps of the response pathway. As a second method of distinguishing the roles of the various STE genes, we examined the sterile mutants for suppression. Mating of the ste2-3 mutant was apparently limited by its sensitivity to alpha-factor, as its sterility was suppressed by mutation sst2-1, which leads to enhanced alpha-factor sensitivity. Sterility resulting from each of four ste4 mutations was suppressed partially by mutation sst2-1 or by mutation bar1-1 when one of three other mutations (ros1-1, ros2-1, or ros3-1) was also present. Sterility of the ste5-3 mutant was suppressed by mutation ros1-1 but not by sst2-1. The ste7, 11, and 12 mutations were not suppressed by ros1 or sst2. Our working model is that STE genes control the response to alpha-factor at two distinct steps. Defects at one step (requiring the STE2 gene are suppressed (directly or indirectly) by mutation sst2-1, whereas defects at the other step (requiring the STE5 gene) are suppressed by the ros1-1 mutation. The ste4 mutants are defective for both steps. Mutation ros1-1 was found to be allelic to cdc39-1. Map positions for genes STE2, STE12, ROS3, and FUR1 were determined.
Import Restrictions in the Presence of a Health Risk: An Illustration Using FMD

We present a simple model linking infection risk from imports to a tariff. The risk causes the exporter of the infected product to face a higher tariff than would otherwise be the case. A numerical example is developed for U.S. beef imports from nations with Foot-and-Mouth Disease (FMD). The additional tariffs are sensitive to the specification of risk and the expected magnitude of loss due to an FMD outbreak. For a low risk of importing FMD, the tariffs levied against the exporter of FMD-infected beef are not prohibitive but become so as the risk or expected output loss rises.
Accountability, Learning, and Response Amid Fiscal Crisis

A national financial collapse can engender a heightened gubernatorial sense of accountability, leadership, and learning. An attempt at theory building on this theme uses governors’ 2009 speeches as...
An In Vitro Biomechanical Comparison of Equine Proximal Interphalangeal Joint Arthrodesis Techniques: An Axial Positioned Dynamic Compression Plate and Two Abaxial Transarticular Cortical Screws Inserted in Lag Fashion Versus Three Parallel Transarticular Cortical Screws Inserted in Lag Fashion

Objectives— To compare in vitro monotonic biomechanical properties of an axial 3-hole, 4.5 mm narrow dynamic compression plate (DCP) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws inserted in lag fashion (DCP-TLS) with 3 parallel transarticular 5.5 mm cortical screws inserted in lag fashion (3-TLS) for the equine proximal interphalangeal (PIP) joint arthrodesis. Study Design— Paired in vitro biomechanical testing of 2 methods of stabilizing cadaveric adult equine forelimb PIP joints. Sample Population— Cadaveric adult equine forelimbs (n=15 pairs). Methods— For each forelimb pair, 1 PIP joint was stabilized with an axial 3-hole narrow DCP (4.5 mm) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws inserted in lag fashion and 1 with 3 parallel transarticular 5.5 mm cortical screws inserted in lag fashion. Five matching pairs of constructs were tested in single cycle to failure under axial compression, 5 construct pairs were tested for cyclic fatigue under axial compression, and 5 construct pairs were tested in single cycle to failure under torsional loading. Mean values for each fixation method were compared using a paired t-test within each group with statistical significance set at P<.05. Results— Mean yield load, yield stiffness, and failure load under axial compression and torsion, single cycle to failure, of the DCP-TLS fixation were significantly greater than those of the 3-TLS fixation. Mean cycles to failure in axial compression of the DCP-TLS fixation was significantly greater than that of the 3-TLS fixation. Conclusion— The DCP-TLS was superior to the 3-TLS in resisting the static overload forces and in resisting cyclic fatigue. Clinical Relevance— The results of this in vitro study may provide information to aid in the selection of a treatment modality for arthrodesis of the equine PIP joint.
Decreasing Lipid Oxidation in Soybean Oil by a UV Absorber in the Packaging Material

The stability and effectiveness of Tinuvin 326”, a UV absorber, dis- persed within the regrind layer of coextruded, multilayered, polypropyl- ene-based containers to protect packaged, bleached soybean oil from photooxidation was investigated. The level of Tinuvin 326 in the con- tainers was determined by using high pressure liquid chromatography (HPLC) and UV spectrophotometric methods. No loss of Tinuvin 326 from the containers was observed over a 42-day storage period at 21 and 35”C, respectively. The migration of Tinuvin 326 from the contain- ers to the oil stored at 35°C was greater than at 21°C. Migration levels at both temperatures, however, were too low to notably reduce Tinuvin 326 levels in the containers. Bleached oil in containers with 0.3% Ti- nuvin 326 underwent less photooxidation than oil in containers with no Tinuvin 326 when exposed to fluorescent light at 21 and 35°C for 35 days. Key Words: soybean oil, lipid oxidation, UV absorber, transparent pack- aging
Protein Kinase G Mediates Vascular Endothelial Growth Factor-induced Raf-1 Activation and Proliferation in Human Endothelial Cells*

Abstract Vascular endothelial growth factor (VEGF) is an endothelium-specific, secreted protein that acts as a vasodilator, angiogenic peptide, and hyperpermeability factor. Recent reports have shown that nitric oxide synthase inhibitors block proliferation and microvascular hyperpermeability induced by VEGF. This study examined the mechanisms by which nitric oxide and its downstream signals mediate the VEGF-induced proliferative response in human umbilical vein endothelial cells (HUVECs). Nitric oxide synthase blockade byN ω-nitro-l-arginine methyl ester prevented both the proliferative effect of VEGF and Raf-1 activation by VEGF as measured by cell counting and the capacity of immunoprecipitated Raf-1 to phosphorylate syntide 2, a Raf-1-specific synthetic substrate. VEGF-induced proliferation and Raf-1 kinase activity were also inhibited by Rp-8-pCPT-cGMPs and KT5823, inhibitors of the regulatory and catalytic subunits of cGMP-dependent protein kinase (PKG), respectively. The ability of PKG to stimulate proliferation was verified by the observation that the PKG activator, 8-pCPT-cGMPs, stimulated both Raf-1 kinase activity and endothelial proliferation in a dose-dependent manner. Furthermore, recombinant catalytically active PKG phosphorylated and activated Raf-1 in a reconstituted system. Finally, Raf-1 immunoprecipitated from VEGF-stimulated endothelial cells coprecipitated with PKG, indicating a direct protein-protein interaction in activated cells. We conclude that VEGF induces increases in both proliferation and Raf-1 kinase activity in HUVECs and these activities are dependent on NO and its downstream effector, PKG.
Improving performance of TCP over wireless networks

Transmission Control Protocol (TCP) assumes a relatively reliable underlying network where most packet losses are due to congestion. In a wireless network, however, packet losses will occur more often due to unreliable wireless links than due to congestion. When using TCP over wireless links, each packet loss on the wireless link results in congestion control measures being invoked at the source. This causes severe performance degradation. In this paper, we study the effect of: burst errors on wireless links; packet size variation on the wired network; local error recovery by the base station; and explicit feedback by the base station, on the performance of TCP over wireless networks. It is shown that the performance of TCP is sensitive to the packet size, and that significant performance improvements are obtained if a good packet size is used. While local recovery by the base station using link-level retransmissions is found to improve performance, timeouts can still occur at the source, causing redundant packet retransmissions. We propose an explicit feedback mechanism, to prevent these timeouts during local recovery. Results indicate significant performance improvements when explicit feedback from the base station is used. A major advantage of our approaches over existing proposals is that no state maintenance is required at any intermediate host. Experiments are performed using the Network Simulator (NS) from Lawrence Berkeley Labs. The simulator has been extended to incorporate wireless link characteristics.
Ingroup Identification as the Inclusion of Ingroup in the Self

This article presents a basic conceptualization of ingroup identification as the degree to which the ingroup is included in the self and introduces the Inclusion of Ingroup in the Self (IIS) measure to reflect this conceptualization. Using responses from samples of women and ethnic minority groups, four studies demonstrate the utility of this conceptualization of ingroup identification and provide support for the IIS. Results from these studies establish construct validity, concurrent and discriminant validity, and high degrees of test-retest reliability for the IIS. Reaction time evidence also is provided, supporting the use of the IIS as a measure of ingroup identification. Particular strengths of this conceptualization of ingroup identification and potential uses for the IIS are discussed.
Ram accelerator - A new chemical method for accelerating projectilesto ultrahigh velocities

A new method for accelerating projectiles from velocities of ~0.7 km/s up to -12 km/s using chemical energy is presented in this paper. The concept, called the "ram accelerator," is based on gasdynamic principles similar to those of an airbreathing ramjet but operates in a different manner. The projectile, which resembles the center body of a ramjet, travels through a tube filled with a premixed gaseous fuel and oxidizer mixture. The tube becomes the outer cowling of the ramjet, and the energy release process travels with the projectile. By tailoring the propellant mixture along the tube, a nearly constant acceleration can be achieved. In principle, the ram accelerator can be scaled for projectile masses ranging from grams to hundreds of kilograms and is capable of ballistic efficiencies as high as 30%. A straightforwar d, quasisteady, one-dimensional approach is used to model the acceleration process. The experimental facility developed to investigate the concept is described, and the results of recent experiments are presented. The velocity range of 690-1500 m/s has been explored in a 4.88-m long, 38-mm bore accelerator tube. Using methane, oxygen, and various diluents, accelerations of up to 16,000 g have been achieved with 75 gm projectiles and gas fill pressures of 20 atm. Proof of concept has been demonstrated, and agreement between theory and experiment has been found to be very good.
Injectable gel graft for bone defect repair

Aim: To examine the performance of an injectable gel graft made of transglutaminase (Tg)-crosslinked gelatin gel with BMP - 2 (BMP - 2–Tg–Gel) for bone defect repair in animal models. Materials & methods: BMP - 2 mixed with gelatin gel was crosslinked using Tg. The release of tethered BMP - 2 through autocrine and paracrine pathways was demonstrated by using C2C12 and NIH 3T3 cells, respectively. BMP - 2–Tg–Gel was injected into the induced cranial defect site. After 14 days, the sample was removed for x - ray imaging and histological evaluation. Results: Our in vivo results demonstrated that the injectable Tg–Gel with its osteoconductivity and controllable BMP - 2 activity induced bone formation in our rat models when tethered with BMP - 2. Conclusion: Tg–Gel as an injectable functional bone graft may enable the use of minimally invasive surgical procedures to treat irregular-shaped bone defects. Furthermore, this novel approach is capable of incorporating and controlling the release of therapeutic agents that may advance the science of tissue regeneration.
Two-dimensional inversion technique for satellite airglow data

A technique is described which inverts satellite airglow data producing volume emission rates as functions of altitude and position. The inversion is applied to data obtained when the spacecraft spins in the orbital plane. The altitude and height resolutions are constrained by the geometry chosen to simplify the inversion. The limitations of the method and its implementation on data from the Visual Airglow Experiment onboard the Atmosphere Explorer satellite are discussed. Sample maps of brightness and volume emission rates are shown.
Localized topological changes of the plasma membrane upon exocytosis visualized by polarized TIRFM

Total internal reflection fluorescence microscopy (TIRFM) images the plasma membrane–cytosol interface and has allowed insights into the behavior of individual secretory granules before and during exocytosis. Much less is known about the dynamics of the other partner in exocytosis, the plasma membrane. In this study, we report the implementation of a TIRFM-based polarization technique to detect rapid submicrometer changes in plasma membrane topology as a result of exocytosis. A theoretical analysis of the technique is presented together with image simulations of predicted topologies of the postfusion granule membrane–plasma membrane complex. Experiments on diI-stained bovine adrenal chromaffin cells using polarized TIRFM demonstrate rapid and varied submicrometer changes in plasma membrane topology at sites of exocytosis that occur immediately upon fusion. We provide direct evidence for a persistent curvature in the exocytotic region that is altered by inhibition of dynamin guanosine triphosphatase activity and is temporally distinct from endocytosis measured by VMAT2-pHluorin.
Nuclear Respiratory Factor 1 Plays an Essential Role in Transcriptional Initiation from the Hepatitis B Virus X Gene Promoter

The X gene of hepatitis B virus (HBV) is one of the major factors in HBV-induced hepatocarcinogenesis and is essential for the establishment of productive HBV replication in vivo. Recent studies have shown that the X gene product targets mitochondria and induces calcium flux, thereby activating Ca + -dependent signal transduction pathways. However, regulatory mechanisms of X gene expression have remained unclear. Previous studies had localized a minimal promoter activity to a 21-bp GC-rich sequence located 130 bp upstream of the X protein coding region and showed that there was a cellular protein bound to this DNA. Interestingly, the 21-bp sequence identified as an X gene minimal promoter does not contain any previously identified core promoter elements, such as a TATA box. To better understand the mechanisms of transcriptional initiation of the X gene, we set out to biochemically purify the binding protein(s) for the 21-bp DNA. We report here the identification of the X gene minimal promoter-binding activity as nuclear respiratory factor 1 (NRF1), a previously known transcription factor that activates the majority of nucleus-encoded mitochondrial genes and various housekeeping genes. Primer extension analyses of the X mRNAs show that mutations at the binding site specifically inactivate transcription from this promoter and that a dominant-negative NRF1 mutant and short interfering RNAs inhibit transcription from this promoter. Therefore, NRF1 specifically binds the 21-bp minimal promoter and positively contributes to transcription of the X gene. Simultaneous activation of the X gene and mitochondrial genes by NRF1 may allow the X protein to target mitochondria most efficiently.
Reversing expectations during discourse comprehension

In two event-related potential experiments, we asked whether comprehenders used the concessive connective, even so, to predict upcoming events. Participants read coherent and incoherent scenarios, with and without even so, e.g. ‘Elizabeth had a history exam on Monday. She took the test and aced/failed it. (Even so), she went home and celebrated wildly’, as they rated coherence (Experiment 1) or simply answered intermittent comprehension questions (Experiment 2). The semantic function of even so was used to reverse real-world knowledge predictions, leading to an attenuated N400 to coherent versus incoherent target words (‘celebrated’). Moreover, its pragmatic communicative function enhanced predictive processing, leading to more N400 attenuation to coherent targets in scenarios with than without even so. This benefit however, did not come for free: the detection of failed event predictions triggered a later posterior positivity and/or an anterior negativity effect, and costs of maintaining alternative like...
Inhibition of Clostridium botulinum by p-Hydroxybenzoic Acid n-Alkyl Esters

Twelve straight-chain esters, C 5 to C 14 , C 16 , and C 18 , of p -hydroxybenzoic acid were prepared, and their melting points, solubilities in water at 25°C, infrared spectra, dissociation constants ( pK a ), and activities against Clostridium botulinum were determined. These studies also included four commercial straight-chain esters, C 1 to C 4 . The most potent activity was exhibited by undecyl and dodecyl esters, which are about 300 times as active as sodium nitrite. Quadratic and cubic equations were developed correlating the activity with pK a values and chain length of the esters, respectively.
Immunophilin ligands can prevent progressive dopaminergic degeneration in animal models of Parkinson's disease.

Slowing or halting the progressive dopaminergic (DA) degeneration in Parkinson’s disease (PD) would delay the onset and development of motor symptoms, prolong the efficacy of pharmacotherapies and decrease drug-induced side-effects. We tested the potential of two orally administered novel immunophilin ligands to protect against DA degeneration in two animal models of PD. First, in an MPTP (N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) mouse model, we compared an immunophilin ligand (V10,367) documented to bind the immunophilin FKBP12 with V-13,661, which does not bind FKBP12. Both molecules could prevent the loss of striatal DA innervation in a dose-dependent fashion during 10 days of oral administration. Second, to determine whether an immunophilin ligand can protect against progressive and slow DA degeneration typical of PD, an intrastriatal 6-hydroxydopamine-infusion rat model was utilized. Oral treatment with the FKBP12-binding immunophilin ligand began on the day of lesion and continued for 21 days. At this time point, post mortem analyses revealed that the treatment had prevented the progressive loss of DA innervation within the striatum and loss of DA neurons within the substantia nigra, related to functional outcome as measured by rotational behaviour. Notably, DA fibres extending into the area of striatal DA denervation were observed only in rats treated with the immunophilin ligand, indicating neuroprotection or sprouting of spared DA fibres. This is the first demonstration that immunophilin ligands can prevent a slow and progressive DA axonal degeneration and neuronal death in vivo. The effects of orally administered structurally related immunophilin ligands in acute and progressive models of DA degeneration are consistent with the idea that these compounds may have therapeutic value in PD.
Role of topoisomerase I inhibitors in small-cell lung cancer.

Abstract Lung cancer continues to be the leading cause of cancer-related death in the United States. Small-cell lung cancer constitutes 15%–20% of all cases of lung cancer. It is a chemosensitive disease with an overall response rate of 70%–90% in first-line treatment. However, the majority of patients relapse, and further treatment at that time is unlikely to achieve a durable response. Among the new drugs studied in this disease, topoisomerase I inhibitors are emerging as active agents with significant activity in both untreated and relapsed disease. This paper reviews the current status of irinotecan and topotecan in the treatment of small-cell lung cancer.
Alterations in β-amyloid production and deposition in brain regions of two transgenic models

Abstract Mutations in the amyloid precursor protein (APP) gene are associated with altered production and deposition of amyloid beta (Aβ) peptide in the Alzheimer’s disease (AD) brain. The pathways that regulate APP processing, Aβ production and Aβ deposition in different tissues and brain regions remain unclear. To address this, we examined levels of various APP processing products as well as Aβ deposition in a genomic-based (R1.40) and a cDNA-based (Tg2576) transgenic mouse model of AD. In tissues, only brain generated detectable levels of the penultimate precursor to Aβ, APP C-terminal fragment-β. In brain regions, holoAPP levels remained constant, but ratios of APP C-terminal fragments and levels of Aβ differed significantly. Surprisingly, cortex had the lowest steady-state levels of Aβ compared to other brain regions. Comparison of Aβ deposition in Tg2576 and R1.40 animals revealed that R1.40 exhibited more abundant deposition in cortex while Tg2576 exhibited extensive deposition in the hippocampus. Our results suggest that AD transgenic models are not equal; their unique characteristics must be considered when studying AD pathogenesis and therapies.
Cellular thyroid peroxidase (TPO), unlike purified TPO and adjuvant, induces antibodies in mice that resemble autoantibodies in human autoimmune thyroid disease.

Autoantibodies to several protein antigens in human autoimmunity interact with a restricted range of epitopes, whereas diverse epitopes are recognized by antibodies induced in animals using antigen and adjuvant. To examine the basis for this difference, we compared the qualitative nature of antibodies developing in AKR/N mice injected with purified thyroid peroxidase (TPO) and adjuvant or with TPO expressed on major histocompatibility complex (MHC) class II+ fibroblasts. Mice injected with purified TPO had higher TPO antibody levels than TPO+/class II+ fibroblast-treated mice. Despite lower titers, recipients of TPO+/class II+ cells developed very high affinity antibodies (Kd = ∼10−10 m), comparable with those of human TPO autoantibodies and about 10-fold higher than those in purified TPO plus adjuvant-immunized mice. Moreover, more than 90% of TPO antibodies in TPO+/class II+ fibroblast-injected mice, compared with only approximately 50% in TPO plus adjuvant-immunized mice, were to the immunodominant reg...
The Schizosaccharomyces Pombe Actin-Related Protein, Arp3, Is a Component of the Cortical Actin Cytoskeleton and Interacts With Profilin

The gene encoding the actin-related protein Arp3 was first identified in the fission yeast Schizosaccharomyces pombe and is a member of an evolutionarily conserved family of actin-related proteins. Here we present several key findings that define an essential role for Arp3p in the functioning of the cortical actin cytoskeleton. First, mutants in arp3 interact specifically with profilin and actin mutants. Second, Arp3 localizes to cortical actin patches which are required for polarized cell growth. Third, the arp3 gene is required for the reorganization of the actin cytoskeleton during the cell cycle. Finally, the Arp3 protein is present in a large protein complex. We believe that this complex may mediate the cortical functions of profilin at actin patches in S. pombe.
A Freshman Engineering Curriculum Integrating Design and Experimentation

A pilot freshman curriculum has been designed and implemented in the Mechanical Engineering Department at the Rochester Institute of Technology. The four-course sequence gives freshmen an overview of a broad range of mechanical engineering activities, ranging from system design and project management, electronics and programming, to technical writing and presentations. Students take a two-quarter ‘Introduction to Mechanical Engineering Design’ course and a two-quarter ‘Measurements, Instrumentation, and Controls’ course. In each sequence, the first course gives students most of the basic tools they will need and the second is centered on an electromechanical Rube Goldberg design project, undertaken by the whole class. Students develop the design concept, build the system, and prove that it works. They are able to practice skills such as communications, teamwork, time management, and experimentation. The integrated first-year course sequences have been offered for two years and have proved successful. The ...
Comparison of various activated partial thromboplastin reagents in the laboratory control of heparin therapy.

The activated partial thromboplastin time (APTT) is being used by an increasing number of laboratories to monitor heparin anticoagulation. Numerous commercial sources of partial thromboplastin are available. These are used in conjunction with one of three activators, (1) kaolin, (2) celite, or (3) ellagic acid, and with varying concentrations of calcium chloride. The current study was undertaken to evaluate several widely used commercial reagents to determine whether comparable results are obtained when reagent systems are interchanged. A plasma pool was prepared and aliquots of it were adjusted to contain specific heparin concentrations ranging from 0.0 to 1.2 units per ml. Each of these aliquots was tested with reagents from six different manufacturers, using Fibrometer methodology according to the manufacturers’ instructions. The results vary considerably according to the manufacturers’ products used in the performance of the test
Demographic Effects on Household Formation Patterns

This paper shows that part of the changes in household formation patterns in the United States can be attributed to changes in the demographic composition of the population. Influential factors include the increasing proportion of elderly in the population and the aging of the baby boom generation. The proportion living alone is expected to rise, the proportion sharing quarters with unrelated persons is expected to fall, and the numbers of persons choosing each of those living styles will rise. In addition, dramatic increases in the demand for both owner-occupied and renter-occupied housing for one-person households are predicted.
Telephone in medical practice

The telephone is increasingly used as a means of communications between patients and physicians. It has several advantages (mainly for the patient), but also several drawbacks (mainly perceived by the physician). Specific training in telephone interview techniques, including possible pitfalls, should be offered to all medical students.