cssi/SciSciGPT-SciSciNet huggingface dataset:
Simulation study on the CO2-driven enhanced gas recovery with sequestration versus the re-fracturing treatment of horizontal wells in the U.S. unconventional shale reservoirs

Abstract It is proposed that very low permeability formations are possible candidates for CO 2 sequestration. Further, experimental studies have shown that shale formations have huge affinity to adsorb CO 2 , the order of 5 to 1 compared to the methane. Therefore, potential sequestration of CO 2 in shale formations leading to enhanced gas recovery (EGR) will be a promising while challenging target for the oil and gas industry. On the other side, hydraulic re-fracturing treatment of shale gas wells is currently gaining more attention due to the poor performance of shale gas reservoirs after a couple years of production. Hence, investigating and comparing the performance of CO 2 -EGR with the re-fracturing treatment is essential for the future economic viability of depleted shale gas reservoirs. This paper presents a systematic comparison of the effect of these two processes on improving gas production performance of unconventional reservoirs, which is not well understood and has not been studied thoroughly in the literature. In this paper, a shale gas field data has been evaluated and incorporated in our simulations for both CO 2 -EGR and re-fracturing treatment purposes. Numerical simulations are performed using local grid refinement (LGR) in order to accurately model the non-linear pressure drop. Also, a dual-porosity/dual-permeability model is incorporated in the reservoir simulation model. Further, the uncertainties associated with inter-related set of geologic and engineering parameters are evaluated and quantified for re-fracturing treatment through several simulation runs. This comprehensive sensitivity study helps in understanding the key reservoir and fracture properties that affect the production performance and enhanced gas recovery in shale gas reservoirs. The results showed that re-fracturing treatment outperforms CO 2 -EGR due to the pronounced effect on cumulative methane gas production. Moreover, the sensitivity analysis showed that the characteristics of reservoir matrix including permeability and porosity are the most influential parameters for re-fracturing treatment. The findings of this study recommend hydraulic re-fracturing of shale reservoirs at first for enhancing gas production followed by CO 2 injection at a later time. This work provides field operators with more insight into maximizing gas recovery from unconventional shale gas reservoirs using re-fracturing stimulation, CO 2 injection, or a combination of both methods.
Acute surgical emergencies in inflammatory bowel disease.

Abstract Background: Acute surgical emergencies in patients with inflammatory bowel disease may carry a substantial morbidity, but fortunately today, a low mortality. The aim of this review is to delineate the treatment of acute surgical emergencies that occur in patients with ulcerative colitis and Crohn’s disease. Methods: Suitable English language reports were identified using PubMed search. Results: Inflammatory bowel disease can present in numerous ways as an acute surgical emergency. These include toxic colitis, hemorrhage, perforation, intra-abdominal masses or abscesses with sepsis, and intestinal obstruction. Toxic colitis and perforation are best managed with intestinal resection and fecal diversion. Hemorrhage in ulcerative colitis initially requires colectomy with rectal preservation and ileostomy. In Crohn’s disease hemorrhage is often focal and localization and segmental resection are performed. Intra-abdominal abscesses should initially be attempted by computed tomography-guided percutaneous drainage followed subsequently by definitive resection. Perianal disease requires abscess drainage with minimal tissue trauma. Intestinal obstruction should be initially managed nonoperatively, with surgery reserved for complete obstruction or intractability. Conclusions: Acute surgical emergencies in patients with inflammatory bowel disease are rare and can have a high morbidity. With a multidisciplinary approach, morbidity can be reduced and patients can have a rapid return and improved quality of life.
Distribution and food habits of two similar species of Bothrocara (Perciformes: Zoarcidae) in the eastern Bering Sea

Six of the eight currently recognized species of the zoarcid genus Bothrocara are known from the eastern Bering Sea. Two of these species, B. brunneum and B. zestum, are widespread and commonly encountered on the upper continental slope, although B. zestum was not widely recognized as a distinct species in the region until 2004. During the summers of 2004 and 2008, large-scale bottom trawl surveys were conducted along the upper continental slope of the eastern Bering Sea from Bering Canyon to the U.S.-Russian border. Over the course of these surveys, distribution, relative abundance, length frequency, length-weight, and stomach contents information was collected for B. brunneum and B. zestum. Data collected on the surveys indicate that these two species have broadly overlapping geographic and bathymetric distributions in the region, but that their population numbers are substantially different. Length-weight regressions show that although these two species reach approximately the same maximum length, B. brunneum is substantially heavier than B. zestum at all lengths over about 40 cm. Stomach contents analysis indicates that the diet of B. brunneum consists primarily of various species of shrimps and mysids, while B. zestum is primarily piscivorous, consuming primarily bathylagids and other zoarcids. Therefore, despite their general morphological similarity, these two species function very differently in the eastern Bering Sea benthic ecosystem.
Universal Behavior of One-Dimensional Gapped Antiferromagnets in a Staggered Magnetic Field

We study the properties of one-dimensional gapped Heisenberg antiferromagnets in the presence of an arbitrary strong staggered magnetic field. For these systems we predict a universal form for the staggered magnetization curve. This function, as well as the effect the staggered field has on the energy gaps in longitudinal and transversal excitation spectra, are determined from the universal form of the effective potential in O(3)-symmetric 1+1–dimensional field theory. Our theoretical findings are in excellent agreement with recent neutron scattering data on R2BaNiO5 (R = magnetic rare earth) linear-chain mixed spin antiferromagnets. One-dimensional isotropic Heisenberg antiferromagnets with an exchange gap in the magnetic excitation spectrum have been at the center of theoretical and experimental attention for almost two decades. This class of materials includes integer-spin Heisenberg chains [1] (commonly referred to as Haldane-gap systems) and halfinteger spin ladders with an even number of legs [2]. Due to the presence of strong quantum fluctuations in these systems the staggered magnetization has a finite correlation length. The principal feature of the excitation spectrum is a degenerate triplet of sharp spin-1 excitations commonly referred to as magnons, separated from the ground state by a finite energy gap �. In recent years much work was aimed at understanding the behavior of such gapped 1D antiferromagnets in the presence of an external uniform magnetic field [3–5]. However, the effect of a staggered field, that couples directly to the order parameter of the classical system, has not been investigated in sufficient detail. This is mainly due to the fact that a strong magnetic field modulated on the microscopic scale was thought to be all but impossible to realize experimentally [6]. A breakthrough came with neutron scattering experiments on R2BaNiO5 (R = magnetic rare-earth) linear-chain nickelates and their interpretation in terms of non-interacting Haldane spin chains immersed in a strong effective staggered exchange field [7,8]. In R2BaNiO5 compounds almost perfectly isotropic antiferromagnetic S = 1 chains are formed by the Ni 2+ ions. The effective staggered field is generated by the R 3+ sublattice that becomes ordered magnetically below some Neel temperature TN. The staggered field intensity is proportional to the magnitude of the ordered moment
Some possibilities in on-line analysis-test procedures for earth structures

Abstract A procedure for finite element analysis of earth structures in which the stress-strain relations are obtained experimentally as the test proceeds is explored. This requires on-line interactions between the analysis and test results, with the behavior if the soil influencing loading history on the soil samples in the appropriate way. In general, one soil sample is required for each integration point in the finite element mesh, However the number of soil samples required can be reduced by use of a limited number of Ritz modes to represent the deformations. Important recent advances in pseudodynamic test methodology applied to building structures are adapted for use in this on-line analysis-test method. The need to enforce compatibility as well as equilibrium makes this a non-trivial step. A further extension of the method allows dissipation of pore pressures to be accounted for. This is achieved by including the nonlinear generalization of Biot's equations in the analytical part of the procedure.
The role of histidine-42 in the oxidation-reduction mechanism of Chromatium vinosum high potential iron-sulfur protein

The second order rate constants for the oxidation of high potential iron-sulfur protein (Hipip) of Chromatium vinosum by ferricyanide were determined as a function of ionic strength and pH. From the ionic strength results, calculations were done to correct the rate constant at each pH for the electrostatic interactions between Hipip and ferricyanide. The electrostatic corrections are necessary since the charge of the protein changes as a function of pH and can mask the ionization of mechanistically important amino acid residues. An apparent pKa congruent to 7 was obtained from electrostatically corrected rate-pH profile, indicating the possible participation of histidine. Perturbation difference spectroscopic studies of Hipip as a function of pH also gave apparent pKa values of 6.9 and 6.7 for the reduced and oxidized protein, respectively. That it was indeed His 42 (the only His in the polypeptide) that was responsible for the kinetic and spectroscopic pKa values was demonstrated by modification of His 42 of Hipip by the histidine selective reagent diethylpyrocarbonate. No modification of Tyr 19 could be detected. It is concluded that either deprotonation or modification of His 42 results in the destabilization of the reduced cluster and thus a faster rate of oxidation. This work provides the first experimental evidence of the 'squeeze effect' mechanism (Carter, C.W., Jr., Kraut, J., Freer, S.T. and Alden, R.A. (1974) J. Biol. Chem. 249, 6339--6346) in which the polypeptide directly modulates the stability of the iron-sulfur cluster.
Vapor pressure and thermodynamics of gaseous TlCl and Tl2Cl2

Abstract Vapor pressures of Tl 2 Cl 2 (g) are measured relative to TlCl(g) by Knudsen-effusion mass spectrometry in the temperature range 543 to 615 K. Pressures are determined by comparison with the known vapor pressure of TlCl(g). The vapor pressure of Tl 2 Cl 2 (g) can be represented by the equation: ln( p /atm) = 19.158 – 20315(K/ T ), ( T = 543 to 615 K). Thermodynamic functions are presented for TlCl(g) and Tl 2 Cl 2 (g) based upon recent spectroscopic data. Third-law enthalpy and entropy changes in the process 2TlCl(s) = Tl 2 Cl 2 (g) are ΔH o (298.15 K) = (40.48 ± 1.3) kcal th mol −1 and ΔS o (298.15 K) = (39.26 ± 1.0) cal th mol −1 K −1 . The high-temperature thermodynamic properties of TlCl are discussed by comparison of these results with literature measurements.
Towards a high-energy theory for the Higgs phase of gravity

Spontaneous Lorentz violation due to a time-dependent expectation value for a massless scalar has been suggested as a method for dynamically generating dark energy. A natural candidate for the scalar is a Goldstone boson arising from the spontaneous breaking of a U(1) symmetry. We investigate the low-energy effective action for such a Goldstone boson in a general class of models involving only scalars, proving that if the scalars have standard kinetic terms then at the classical level the effective action does not have the required features for spontaneous Lorentz violation to occur asymptotically (t-->[infinity]) in an expanding Friedman-Robertson-Walker universe. Then we study the large N limit of a renormalizable field theory with a complex scalar coupled to massive fermions. In this model an effective action for the Goldstone boson with the properties required for spontaneous Lorentz violation can be generated. Although the model has shortcomings, we feel it represents progress towards finding a high energy completion for the Higgs phase of gravity.
An accurate ab initio quartic force field and vibrational frequencies for cyclopropenylidene

Abstract The singles and doubles coupled-cluster method that includes a perturbative correction for connected triple excitations, denoted CCSD(T), is used in conjunction with an spdf quality one-particle basis set to determine an accurate quartic force field for cyclopropenylidene. A second-order perturbation theory treatment of vibrational anharmonicities, together with proper treatment of Fermi resonances, is used to predict fundamental vibrational frequencies of cyclopropenylidene and its 13C and deuterium isotopomers. Agreement between theory and the available experimental data is excellent. It is demonstrated that four vibrational bands assigned to cyclopropenylidene in 1984 matrix isolation experiments are correct, contrary to a recent suggestion. The anharmonic progression in the C-H stretches is examined and found to be similar for both the symmetric and antisymmetric C-H stretches, contrary to the findings from another recent study.
Determination of the Carbohydrate-Binding Specificity of Lectin-Like Domains in Vibrio Cholerae Cytolysin

Vibrio cholerae cytolysin (VCC) is a secreted pore-forming toxin that contains two putative sugar-binding domains: the β-trefoil domain and the β-prism domain. Previous hemagglutinating studies suggest that VCC binds glycoproteins with terminal β1-galactosyl moieties [1]; however, crystallization of monomeric VCC with β-octyl glucoside suggests the β-prism domain may have an affinity for glucosides. We aim to characterize the carbohydrate-binding specificity of the β-trefoil and β-prism domains. The crystal structure of VCC indicates that Asp617 within the β-prism domain forms hydrogen bonds with the bound glucoside moeity. Hemolysis assays demonstrated that the removal of the β-prism domain causes a 1000-fold decrease in lytic activity toward rabbit erythrocytes, while conversion of Asp617 to alanine and lysine decreases the hemolytic activity100-fold, indicating that the sugar-binding activity of VCC may play a role in cell lysis. The β-prism domain was expressed as a separate construct and isothermal titration calorimetry (ITC) was used to determine the binding affinity for the interaction of the β-prism domain with monosaccharides. The binding of the isolated β-prism domain reflected the binding affinities observed using ITC for full length VCC. The β-prism domain showed an affinity for mannose, but not galactose, indicating that recognition of terminal β1-galactosyl moieties does not occur at the β-prism domain. The carbohydrate-binding activity of the β-prism domain may explain its role in cell lysis.[1] Saha, N; Banerjee, K.K. Carbohydrate-mediated Regulation of Interaction of Vibrio cholerae Hemolysin with Erythrocyte and Phospholipid Vesicle, J. Biol. Chem. (1997) 272, 162-167.
Nonlinear prediction in image coding with DPCM

In contrast to the traditional linear differential pulse code modulation (DPCM) design for the encoding of images, a new, nonlinear, neural network-based, DPCM technique has been devised. The predictor is designed by supervised training, based on a typical sequence of pixel values in an image. A function link neural network architecture has been used to design the predictor for one dimensional (1-D) DPCM. Computer simulation experiments in still image coding have shown that the resulting encoders work very well. At a transmission rate of 1 bit/pixel, for the image LENA, the 1-D neural network DPCM provides a 4.2 dB improvement in SNR over the standard linear DPCM system.
What Makes Rabbit Run?: Updike's Hero as Tocqueville's American Democrat

This article deals with one aspect of the political imagination that has been neglected by modern political scientists, namely, the use of literature to make essentially political points. It demonstrates that John Updike's Rabbit trilogy is properly read as a fictional representation of Alexis de Tocqueville's classic Democracy in America. Updike's stories reveal that the anomie, alienation, and mediocrity predicted as consequences of democracy by Tocqueville 150 years ago have become concrete dilemmas facing contemporary Americans in their daily situations and experiences.
Expression of Toll/IL-1R domain-containing adaptor protein (TIRAP) is detrimental to primary clearance of Salmonella and is not required for the generation of protective immunity

Salmonella infection triggers activation of innate immune cells through the interaction of bacterial products with Toll-like receptors (TLRs). Toll/IL-1R domain-containing adaptor protein (TIRAP) is an adaptor protein involved in downstream signaling through TLRs 1, 2, 4, and 6. We examined the role of TIRAP during infection with attenuated Salmonella. Surprisingly, TIRAP-deficient mice were fully capable of resolving primary infection with Salmonella and actually exhibited accelerated clearance of bacteria at a late stage of the infection. Consistent with enhanced bacterial clearance, TIRAP-deficient mice resolved bacterial-associated splenic inflammation more rapidly than wild-type (Wt) mice and splenocytes from Salmonella-infected TIRAP-deficient mice produced more IFN-γ upon in vitro re-stimulation. Upon secondary challenge, TIRAP-deficient and Wt mice displayed a similar level of protective immunity against virulent Salmonella. Together these data indicate that TIRAP-mediated signaling is completely dispensable for clearance of Salmonella infection, and actually has a mild deleterious effect upon the resolution of primary infection.
Random phase data masks: fabrication tolerances and advantages of four phase level masks.

An analysis is presented of the intensity variations in the Fourier transform plane resulting from the use of a bilevel random phase mask for holographic data recording as suggested by Burckhardt. To maintain a fixed ratio of peak intensities between in-phase amplitude components and out-of-phase components for an imperfect phase mask, the permissible error in the phase shift varies as 1/N, where N is the number of apertures in the data mask. A factor of 212 reduction in the rms intensity fluctuations in both the Fourier transform plane where the hologram is recorded and in the retrieved image may be obtained by using four levels of phase shift. No further improvement is obtained with additional levels.
Aubrites and diogenites - Trace element clues to their origin

A typically igneous siderophile element pattern emerges from an RNAA analysis of 25 aubrite and nine diogenite samples for 13-29 siderophile, volatile, and lithophile trace elements, although it is noted that abundances are about 10 times higher in the case of aubrites. Se is also surprisingly abundant in aubrites. Factor analysis shows several parallel groupings for aubrites and diogenites. Several element pairs that differ greatly in volatility correlate closely in aubrites, in approximately C1-chondrite proportions, suggesting that aubrites originated by igneous processes in their parent body.
Operating Characteristics of a Subset Selection Procedure Applied to a Hybrid Randomized Response Model

The operating characteristics (OCs) of a subset ranking and selection procedure are derived for the hybrid randomized response model developed by Jia and McDonald (2009). The OCs include the probability of a correct P(CS), the individual selection probability γi, and the expected subset size E(S), under the slippage configuration or the equi-spaced configuration. An example comparing failure rates of contraceptive methods is used to illustrate the use of these new results.
c-myc as an inducer of polycystic kidney disease in transgenic mice

In this study, a genetic model of polycystic kidney disease (PKD) has been produced in transgenic mice bearing the murine c-myc gene driven by the SV40 enhancer and the adult beta-globin promoter. These animals reproducibly develop PKD and die of renal failure. The phenotype appears to result from the overexpression of c-myc in the renal tubular epithelium and consequent abnormal cell proliferation. These transgenic mice represent a genetic model of PKD which bears similarities to human autosomal dominant PKD (ADPKD) with respect to renal morphology, renal functional alterations and dominant transmission. Study of these transgenic mice may offer valuable insights into the pathogenesis of PKD.
The emergence of online widescale interaction in unexpected events: assistance, alliance & retreat

This paper examines online, widescale interaction during an emergency event of national interest. Widescale interaction describes the potential for broad, immediate, and varied participation that the conditions of online forums, and social networking sites in particular, increasingly allow. Here, we examine a group on a popular social networking site as a virtual destination in the aftermath of the Northern Illinois University (NIU) shootings of February 14, 2008 in relation to related activity that happened in response to the Virginia Tech (VT) tragedy 10 months earlier. We consider features of interactions that are enabled when a vast audience converges under such conditions. We discuss how commiseration and information seeking are interrelated, and how geographical communities that share a common experience ally in such a public, online setting.
Mitral Valve Prolapse in Association With Mitral Valve Stenosis Echocardiographic And Angiographic Features

Echocardiograms and left ventricular angiograms were systematically studied in 20 consecutive patients with hemodynamically proven mitral stenosis who were in sinus rhythm. "Definite" mitral valve prolapse was present on the echograms of 9 of 20 patients (45%), while "possible" mitral valve prolapse was noted on the echograms of 7 of 20 (35%). Of the 9 subjects with definite mitral valve prolapse, 4 had angiographic evidence of this diagnosis and an identical number had mitral regurgitation; 1 patient had both prolapse and mitral regurgitation. No subject with "possible" ultrasonic prolapse or normal systolic mitral valve motion had angiographic mitral valve prolapse. It is concluded that (1) signs of mitral valve prolapse are frequently encountered on the echocardiograms of patients with hemodyn amically proven mitral stenosis who are in sinus rhythm, and (2) when stringent criteria for the echographic diagnosis of prolapse are employed, approximately 50% of affected subjects have concomitant mitral insu...
Brain metastases in patients with breast cancer: new horizons.

Abstract Brain metastases occur in as many as one third of patients with disseminated breast cancer. In this article, we discuss various presentations of brain metastases from breast cancer and review evidence that supports different treatment options. Because no prospective, randomized, controlled studies, to our knowledge, have focused solely on patients with brain metastases from breast cancer, we will first review retrospective studies of patients with brain metastases from breast cancer. Randomized studies of patients with brain metastases caused by multiple primary cancers will also be examined, and the conclusions from these studies will be extrapolated to patients with breast cancer. Because brain metastases from breast cancer occur in a variety of different clinical settings, ranging from a single metastasis without extensive extracranial disease to multiple brain metastases with widespread extracranial disease, treatment approaches must be tailored to the specific circumstances of each patient. For different clinical scenarios, neurosurgical resection, radiosurgery, and/or whole-brain radiation therapy may be appropriate treatment options. For patients with brain metastases from breast cancer that overexpresses HER2/ne u , trastuzumab could alter the natural history of the non—central nervous system (CNS) disease. Therefore, HER2 status could also influence the treatment of brain metastases from breast cancer. Given the prevalence of brain metastases in patients with metastatic breast cancer in contemporary series, the rationale for clinical trials of CNS screening and prophylactic cranial irradiation will be discussed.
Acousto-optically tuned isotopic CO 2 lasers for long-range differential absorption lidar

The authors are developing 2--100 kHz repetition rate CO{sub 2} lasers with milliJoule pulse energies, rapid acousto-optic tuning and isotopic gas mixes, for Differential Absorption LIDAR (DIAL) applications. The authors explain the tuning method, which uses a pair of acousto-optic modulators and is capable of random access to CO{sub 2} laser lines at rates of 100 kHz or more. The laser system is also described, and they report on performance with both normal and isotopic gas mixes.
Optimal network reconfigurations in distribution systems. II. Solution algorithms and numerical results

Using a two-stage solution methodology and a modified simulated annealing technique, the authors develop a solution algorithm to the network reconfiguration problem, which is a constrained, multiobjective, nondifferentiable, optimization problem. This solution algorithm allows the designer to obtain a desirable, global noninferior point in a reasonable computation time. Also, given a desired number of switch-on/switch-off operations involved in the network configuration, the solution algorithm can identify the most effective operations. In order to reduce the computation time required, the idea of approximate calculations is explored and incorporated into the solution algorithm, where two efficient load-flow methods are employed; one for high temperature and the other for low temperature. The solution algorithm has been implemented in a software package and tested on a 69-bus system with very promising results. >
A Typology of Child Protective Services Cases Based on Client Presenting Problems

Child maltreatment often is associated with other personal, interpersonal, and environmental problems. Consequently, the ability to chracterize the type and level of child maltreatment in a family, alone, does not always provide sufficient insight into the family's current problems and service needs. In this study, all the cases sampled had documented instances of child maltreatment, and all had at least one additional presenting problem. Sets of interrelated current problems were empirically derived and used to sort child welfare cases into four groups. These groups were distinguished by the presence of problems related to (1) parent behavior and characteristics, (2) poverty, (3) an amalgam of parent behavior and poverty, and (4) child behavior and characteristics. This fourgroup typology is used to frame a discussion of the service needs of these families. Implications for development of agency-specific case typologies are presented.
Electrical and chemical excitability appear one week before birth in the embryonic rat spinal cord

Abstract Embryonic rat spinal cord cells were acutely dissociated with the enzyme papain, stained with a voltage-sensitive oxonal dye and incubated with various pharmacological agents. Changes in the fluorescence intensity and, by inference, membrane potential of the cells were analyzed in a flow cytometer. Veratridine caused depolarization of the cells in a TTX-sensitive manner from as early as embryonic day 13. Depolarizing responses to muscimol and kainate appeared slightly later, at embryonic days 14 and 15, and were blocked by the antagonists bicuculline and CNQX, respectively. Responses to veratridine and kainate did not occur in sodium-free medium. The emergence of these excitable membrane properties coincides with postmitotic differentuation and synaptic development in the embryonic spinal cord.
INITIATION AND DEVELOPMENT OF INFLORESCENCE AND FLOWER IN ANEMOPSIS CALIFORNICA (SAURURACEAE)

All flowers of Anemopsis californica, the most specialized taxon of the family Saururaceae, are initiated as individual primordia subtended by previously initiated bracts, in contrast to the common-primordium initiation of all flowers of Saururus cernuus and of most flowers of Houttuynia cordata. Floral symmetry is bilateral and zygomorphic, and the sequence of initiation among floral parts is paired or whorled. In A. californica, the six stamens arise as three common primordia, each of which later bifurcates to form a pair. The three common primordia occupy sites corresponding to the positions of the three stamens in H. cordata flowers. In Anemopsis, the filaments of each pair are connate. Each stamen pair is vascularized by a single bifurcating vascular bundle. The three carpels per flower are usually initiated simultaneously although there may be some variation. Adnation between stamens and carpels results from zonal growth. Downward extension of the locule, and proliferation and expansion of receptacular tissue and inflorescence cortical tissue around the locule below the bases of the carpels produce the inferior ovary. The inflorescence terminates its activity as a flattened apical residuum, surrounded by
Neural correlates of temporal integration in the cochlear nucleus of the chinchilla

Single unit thresholds were measured as a function of stimulus duration for Primary-like and Chopper units in the anteroventral cochlear nucleus (AVCN) of the chinchilla to examine the neural correlates of temporal integration. Thresholds were measured with a two-alternative, forced-choice (2AFC) adaptive tracking procedure. The time constants and the slopes of the threshold-duration functions were estimated by fitting the threshold data with an exponential function and a power law function. The results showed that Primary-like units exhibited greater threshold improvement and a longer time constant than Chopper units. Units with low characteristic frequencies (CF) showed a larger decrease in threshold with increasing duration and a longer time constant than mid-CF or high-CF units. Units with low spontaneous rates (SR) showed a smaller threshold decrease with increasing duration and a shorter time constant than mid-SR or high-SR units. The single unit time constants and the rate of threshold improvement are similar to those measured psychophysically in the chinchilla.
Boys Just Want to Have Fun? Masculinity, Sexual Behaviors, and Romantic Intentions of Gay and Straight Males in College

Scholars studying college student sexual culture in the United States largely frame men as being detached from emotions, unconcerned with relationships, and in pursuit of sexual conquests. By expanding the examination of college sexual culture, an environment often associated with meaningless sexual encounters, this article tests those stereotypes in gay and straight men. We evaluate sexual behaviors, social opportunity structures, and romantic attitudes of gay and straight males in college. We find evidence that both supports and contradicts existing literature on masculine stereotypes for both groups of men. We also find that gay and straight men report different sexual scripts and romantic desires.
The Effect of Caffeine Ingestion on Perception of Muscle Pain During a Sustained Submaximal Isometric Contraction of the Quadriceps

Methods A total of 15 low caffeine consuming college aged women (20.5 ± 1.4 y, 66.0 ± 9.0 kg; mean ± SD) participated in this study. 2–7 d after a familiarization trial subjects ingested, in a double blind random crossover manner, either 5 mg/kg caffeine (Caf) or a placebo (P), 1 h prior to performing a 2 min isometric leg extension at 45% of peak torque using visual cues to maintain force production. Every 15 s subjects rated their level of pain using the Borg CR10 pain scale. Subjects returned to the lab 2–7 d later to repeat the testing with the other condition. Data were analyzed using a repeated measures ANOVA with a Tukey's HSD post hoc.
The impact of post space preparation with Gates-Glidden drills on residual dentin thickness in distal roots of mandibular molars

ABSTRACT Background Posts frequently are used to retain buildups. The authors examined the effects of post space preparation with Gates-Glidden drills on residual dentin thickness in distal roots of mandibular molars. Methods The authors embedded 26 root-treated mandibular molars in endodontic cubes and sectioned them perpendicularly to their long axis at 1.8-millimeter intervals. They placed Gates-Glidden drills nos. 3, 4, 5 and 6 sequentially to 5 mm short of working length in the distal canals. After using each drill size, the authors measured the dentin thickness from light microscopic images of the tooth slices. Results The authors analyzed data to detect changes resulting from canal instrumentation. They performed statistical analysis by partitioning the variability in a nested analysis of variance. Strip perforations occurred with a no. 4 Gates-Glidden drill 7.3 percent of the time and more frequently with larger drills. After endodontic treatment alone, the canal wall on the furcal side was less than 1 mm thick 82 percent of the time and less than 0.5 mm thick 17.5 percent of the time. Conclusions Dentin thickness correlates inversely to post space diameter. A no. 4 Gates-Glidden drill caused strip perforations in 7.3 percent of the canals studied, and therefore the authors recommend that Gates-Glidden drills larger than a no. 3 not be used in these roots. After endodontic treatment, the furcation-side dentin thickness was less than 1 mm in 82 percent of the teeth. Clinical Implications Post space preparation in mandibular molars carries significant risk of perforation. Post space in such teeth should be limited to the endodontically prepared canal.
The Pesky Power Asymmetry

Physical models for the hemispherical power asymmetry in the cosmic microwave background (CMB) reported by the Planck Collaboration must satisfy CMB constraints to the homogeneity of the Universe and quasar constraints to power asymmetries. We survey a variety of models for the power asymmetry and show that consistent models include a modulated scale-dependent isocurvature contribution to the matter power spectrum or a modulation of the reionization optical depth, gravitational-wave amplitude, or scalar spectral index. We propose further tests to distinguish between the different scenarios.
The Cards that are Dealt You

Various philosophers have argued that in order to be morally responsible, we need to be the "ultimate sources'' of our choices and behavior. Although there are different versions of this sort of argument, I identify a "picture'' that lies behind them, and I contend that this picture is misleading. Joel Feinberg helpfully suggested that we scale down what might initially be thought to be legitimate demands on "self-creation,'' rather than jettison the idea that we are truly and robustly responsible. I follow Feinberg in rejecting various "inflated'' demands on "origination,'' "initiation,'' or ultimate sourcehood.
Semiparametric analysis of the additive risk model

In contrast to the proportional hazards model, the additive risk model specifies that the hazard function associated with a set of possibly time-varying covariates is the sum of, rather than the product of, the baseline hazard function and the regression function of covariates. This formulation describes a different aspect of the association between covariates and the failure time than the proportional hazards model, and is more plausible than the latter for many applications. In the present paper, simple procedures with high efficiencies are developed for making inference about the regression parameters under the additive risk model with an unspecified baseline hazard function
Coordination dynamics in a socially situated nervous system

Traditional theories of cognitive science have typically accounted for the organization of human behavior by detailing the requisite computational or representational functions and identifying neurological mechanisms that might perform these functions. Put simply, such approaches hold that neural activity causes behavior. This same general framework has been extended to accounts of human social behavior via explanatory concepts such as “common-coding” and “co-representation”, and much recent neurological research has been devoted to brain structures that might execute these social-cognitive functions. Although these neural processes are unquestionably involved in the organization of human social interactions, there is good reason to question whether they should be accorded causal primacy. Specifically, research on interpersonal rhythmic motor coordination suggests that the organization of human behavior, including social behavior, can result from self-organizing processes and the lawful dynamics of animal-environment systems. Here we review this research, and in doing so propose that the role of the nervous system in joint action and interpersonal coordination be recast from the sole cause of behavior to one of many interdependent processes.
Geophysical Monitoring Through a Tidal Cycle at Crescent Beach State Park, Maine

This paper presents results of an experiment in which data from a combination of geophysical methods (resistivity, induced polarization, electromagnetic profiling, and magnetic profiling) were used to identify shallow geologic and hydrogeologic structure, and to enhance understanding of groundwater flow in a dynamic beach environment. Based on this study, well sorted beach sand is underlain by laterally variable glacial till, which overlies bedrock. An extensive patch of glacial till was mapped toward the ocean side of the beach. Bedrock has lithologic variability, as evidenced by a non-uniform magnetic response. In particular, a northeast-southwest trending magnetic body, believed to be a basalt dyke, was detected by its magnetic signature. During the transgressive phase of the tidal cycle, saline groundwater flow appeared to be quite rapid, extending ahead of the surfical water by at least 4m, as evidenced by the electromagnetic response. During the regressive phase, a slug of saline water remained up b...
Theory, Fabrication, and Characterization of MEMS Devices: An Interdisciplinary Course for Mechanical Engineers

The need to provide students with hands-on instruction in the fabrication of Microelectromechanical Systems (MEMS) led to the development of an upper-undergraduate, introductory-graduate, laboratory course offered each spring in the Department of Mechanical Science and Engineering (MechSE). The laboratory is taught in a class 100 cleanroom located in, and operated by, the MechSE department. Fabrication and testing of two MEMS device projects, a piezoresistive membrane pressure sensor and a microfluidic logic chip, facilitate the teaching of standard fabrication procedures, fabrication tool operation, and cleanroom protocols. The course appeals across disciplines as evident by half the students coming from other departments (chemical engineering, chemistry, material science, physics, electrical engineering, aeronautical engineering, etc.). The course also serves to attract prospective graduate students as many students continue to use the cleanroom in their graduate level research. This course broadly covers MEMS fabrication theory while maintaining a focus on practical understanding and laboratory application of that theory. The lecture is tied closely to the laboratory work by covering the tool and procedure theory that is used in the lab each week. An exciting aspect of the course is the hands-on learning experience the students get by independently operating the fabrication equipment themselves, including metal deposition tools, reactive ion etch (RIE) tools, lithography tools (spinners, mask aligners, etc.), and bath etchers and cleaners. Safety is an important aspect of the course where students are tested on safety protocol, Material Safety Data Sheet (MSDS) and National Fire Protection Agency (NFPA) familiarity, personal protection procedures, etc. The students also learn benchmark fabrication procedures including standard cleaning protocols (with ultrasonics), the Bosch RIE etching of silicon microstructures, and anisotropic etching of silicon. The piezoresistive membrane pressure sensor project facilitates an understanding of the residual stresses involved in thin-film deposition, stress-strain relationships, and signal analysis for transduction mechanisms. The microfluidic logic chip project, a chip of logic gates (NAND, NOR, etc.) and a half-adder, facilitates understanding fundamental principles of microfluidics, the Navier-Stokes equation, and flow in microchannels. This course, originally sponsored by Intel Corporation, prepares Mechanical Engineers in a multi-disciplinary environment to learn both the practical fundamentals and the theoretical basis of basic and advanced microfabrication that goes beyond the usual CMOS fabrication theory and methodology taught in Electrical Engineering for the microelectronics bound students. As evident from its popularity, the course also serves to excite and equip students for the important Mechanical Engineering field of MEMS.Copyright © 2006 by ASME
Precision determination of stoichiometry and disorder in multicomponent compounds by vibrational spectroscopy

Abstract This paper describes the use of vibrational spectroscopy to determine with high precision (.001%) the stoichiometry and defect structures of multicomponent compounds. For the first time, measurements have been made of the intrinsic compositional disorder that are more than two orders of magnitude more precise than currently available. These data are essential for the establishment of a scientific base upon which to design specific materials involving multicomponent compounds. Current analytical techniques have left undetected large amounts (0.3% minimum) of disorder that have significant effects on the properties of materials. These measurements establish vibrational spectroscopy as a sensitive tool for the determination of defect structures of all types and result in an experimental technique that will allow the study, in situ , of degradation and failure mechanisms in multicomponent compounds.
Coordinated Participation of Calreticulin and Calnexin in the Biosynthesis of Myeloperoxidase

Myeloperoxidase (MPO) is a neutrophil lysosomal hemeprotein essential for optimal oxygen-dependent microbicidal activity. We have demonstrated previously that calreticulin, a luminal endoplasmic reticulum protein, functions as a molecular chaperone during myeloperoxidase biosynthesis, associating reversibly with the heme-free precursor apopro-MPO. Because the membrane-bound endoplasmic reticulum protein calnexin is structurally and functionally related to calreticulin, we assessed the role of calnexin in myeloperoxidase biosynthesis. Like calreticulin, calnexin coprecipitated exclusively with glycosylated MPO precursors and with apopro-MPO but, in contrast to calreticulin, also with the enzymatically active, heme-containing precursor pro-MPO. To determine if calnexin participated in heme insertion into MPO, we compared the kinetics of chaperone association with MPO precursors using stable transfectants expressing cDNA encoding wild type MPO or mutated forms that do not acquire heme. Transfectants expressing mutant cDNA had prolonged association of MPO-related precursors with calreticulin and especially with calnexin. These studies demonstrate that 1) both calreticulin and calnexin associated with glycosylated apopro-MPO; 2) only calnexin associated selectively with the enzymatically active, heme-containing precursor pro-MPO; and 3) mutants unable to incorporate heme had prolonged association with calnexin. These findings represent the first evidence of a specialized role for calnexin in facilitating protein maturation in the endoplasmic reticulum of myeloid cells.
Cardiovascular magnetic resonance imaging: Current and emerging applications

Magnetic resonance (MR) imaging is gaining importance in cardiology as the newest, most complex, and rapidly emerging noninvasive test of choice for patients with a multitude of cardiovascular problems. It has long been recognized to provide an accurate and reliable means of assessing the function and anatomy of the heart and great vessels, but its emerging role as one of the dominant imaging modalities in other aspects of cardiology such as perfusion imaging, atherosclerosis imaging, and coronary artery imaging cannot be understated. As MR technology evolves, newer therapeutic applications are also being developed, including specific MR-compatible catheters for electrophysiology studies/ablation as well as interventional cardiology related procedures, which may alter the way we practice cardiology in the future. Also, MR is entering an important phasein its evolution, with an anticipated exponential growth in its current applications and through the development of newer molecular imaging applications. It is anticipated that such developments will be coupled to the utilization of molecular markers to index biologic processes to allow for their in vivo visualization. This combination of biochemical markers and imaging methodology will also usher in an era of molecular imaging during which much progress in the diagnosis and treatment of cardiovascular disease is anticipated.
Equine platelet CD62P (P-selectin) expression: a phenotypic and morphologic study

Abstract Acute inflammatory diseases, such as colic, septicemia and endotoxemia are common in equines and have been shown to be correlated to vascular injury and thrombosis. In humans with similar thrombotic conditions, P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1)-mediated platelet–leukocyte adhesion contributes to the pathogenesis of these disorders through the generation of inflammatory mediators and tissue factor. As such, we hypothesized that a P-selectin–PSGL-1 (platelet–leukocyte) interaction, similar to that in humans, may also exist in the horse. The objective of this study was to investigate phenotypic and morphological properties of equine platelet activation with a focus on CD62P (P-selectin) expression and CD62P mediated platelet–leukocyte interactions. To study high levels of platelet activation, we used 1 U/ml thrombin to induce secondary, irreversible aggregation in both human and equine platelets. Addition of glycyl- l -prolyl- l -arginyl- l -proline amide (GPRP) prior to thrombin activation blocked fibrin polymerization, allowing the use of flow cytometry to study α-granule expression as a measure of platelet activation. Thrombin activation resulted in high levels of activation, measured as P-selectin expression, in both humans and equines. Interestingly, our research illustrates that in healthy horses, P-selectin is also constitutively expressed on 20–25% of resting platelets. This finding is in direct contrast to humans, in which P-selectin expression is negligible (
Pressure dependence of donor excitation spectra in AlSb

We have investigated the behavior of ground to bound excited-state electronic transitions of Se and Te donors in AlSb as a function of hydrostatic pressure. Using broadband far-infrared Fourier transform spectroscopy, we observe qualitatively different behaviors of the electronic transition energies of the two donors. While the pressure derivative of the Te transition energy is small and constant, as might be expected for a shallow donor, the pressure derivatives of the Se transition energies are quadratic and large at low pressures, indicating that Se is actually a deep donor. In addition, at pressures between 30 and 50 kbar, we observe evidence of an anti-crossing between one of the selenium electronic transitions and a two-phonon mode.