cssi/SciSciGPT-SciSciNet huggingface dataset:
Numerical Modeling of Liquid Piston Gas Compression

Prior research has shown that the use of liquid-pistons in place of conventional solid pistons within gas compression technologies can significantly improve the efficiency of gas compression. The liquid-piston provides the prospect for a consistent and high rate of heat extraction from the compressed gas during system operation. Consequently, the input power requirements during each individual compression are lowered. To validate this concept, analytical studies of the thermal-fluids and heat transfer mechanisms during gas compression were performed. The analysis involved the development of a numerical model, using the finite-difference method, which simulated a single compression stroke and quantified the crucial parameters during compression. This model was utilized to obtain theoretical efficiency values and to recognize optimal system characteristics. The results obtained from the simulation indicated double-digit increase in efficiency with the introduction of the liquid-piston.Copyright © 2009 by ASME
Distorting temporal fine structure by phase shifting and its effects on speech intelligibility and neural phase locking

Envelope (E) and temporal fine structure (TFS) are important features of acoustic signals and their corresponding perceptual function has been investigated with various listening tasks. To further understand the underlying neural processing of TFS, experiments in humans and animals were conducted to demonstrate the effects of modifying the TFS in natural speech sentences on both speech recognition and neural coding. The TFS of natural speech sentences was modified by distorting the phase and maintaining the magnitude. Speech intelligibility was then tested for normal-hearing listeners using the intact and reconstructed sentences presented in quiet and against background noise. Sentences with modified TFS were then used to evoke neural activity in auditory neurons of the inferior colliculus in guinea pigs. Our study demonstrated that speech intelligibility in humans relied on the periodic cues of speech TFS in both quiet and noisy listening conditions. Furthermore, recordings of neural activity from the guinea pig inferior colliculus have shown that individual auditory neurons exhibit phase locking patterns to the periodic cues of speech TFS that disappear when reconstructed sounds do not show periodic patterns anymore. Thus, the periodic cues of TFS are essential for speech intelligibility and are encoded in auditory neurons by phase locking.
Resection of Intrathoracic Paraganglioma With and Without Cardiopulmonary Bypass.

Background Intrathoracic paragangliomas (PGLs) are rare tumors. Approximately 50% originate from and around cardiac structures. Methods A retrospective review was made of the perioperative course of patients with intrathoracic PGL resection from 2000 through 2015 at Mayo Clinic in Rochester, Minnesota. Results Twenty-two patients underwent PGL resection. Sixteen patients (73%) had functioning tumors (11, noradrenergic; 4, mixed noradrenergic and dopaminergic; 1, dopaminergic). Patients with functioning tumors received preoperative adrenergic blockade: 15 (68%), α 1,2 -adrenergic receptor antagonist; 4 (18%), α 1 -adrenergic receptor antagonists; and 13 (59%) metyrosine. Six patients with nonfunctioning tumors had no adrenergic blockade. Twelve patients had tumor resection without cardiopulmonary bypass—9 for PGL associated with the great vessels, 2 for PGL with pericardial involvement, and 1 for PGL in right atrioventricular groove. Ten patients required cardiopulmonary bypass; for 9, the tumor involved cardiac structures and for 1, it involved ascending aorta and proximal aortic arch. Of these, 1 patient had uncontrollable bleeding and died intraoperatively. Other than this single death, there were no inhospital major cardiac or pulmonary complications. Median follow-up was 8.2 years (range, 2.1 to 17.2). Six patients subsequently had metastatic disease, and of them, 1 died 6 years after the operation. Conclusions In this series, 73% of intrathoracic PGLs were functional and involved noradrenergic, mixed noradrenergic and dopaminergic, or pure dopaminergic secretion. Cardiac and pericardial paraganglioma resection may require cardiopulmonary bypass. Although intraoperative bleeding in most complex cases may be uncontrollable, as for 1 of our patients, those who survived hospital discharge had favorable long-term outcomes.
The Organizational Context

It is important to recognize that the four programs we consider in this book are embedded in a larger organization—FEMA—that is responsible for a multitude of emergency management programs. Although the numbers of individuals associated with the programs we consider are relatively few, FEMA itself is substantially larger. To understand the operating context and the overall philosophy of program management, we must look at FEMA in broad organizational and management terms. The unseen hand of relatively large scale bureaucracy looms over individual programs as a factor potentially shaping the management choices and behavior that we consider in our case studies.
Filling in the Moat Around the Ivory Tower

Over the past one hundred and fifty years, higher education in America has undergone fundamental changes. After a long emphasis on teaching, the idea of service to society re-oriented higher education in the mid 19th century, highlighted by the creation of the land-grant universities. Then, over the last century and particularly after the Second World War, the focus shifted toward research, and academic subspecialties proliferated. Now the university finds itself with a tri-partite mission and a sprawling accumulation of autonomous units — a multiversity — with no deeper forces of integration guiding its evolution. The splintered forms of inquiry we have inherited from the past do not always serve well a world in which complex problems are not neatly packaged according to academic disciplines.
Frequency and Characteristics of Biological False-Positive Test Results for Syphilis Reported in Florida and New York City, USA, 2013 to 2017.

ABSTRACT Discordant syphilis test results, with a reactive nontreponemal test and nonreactive treponemal test are usually considered biological false-positive test results (BFPs), which can be attributed to other conditions. Syphilis surveillance laws mandate laboratory reporting of reactive syphilis tests, which include many BFPs. We describe the frequency of BFPs, titer distributions, and titer increases from reported test results in Florida and New York City (NYC). Reactive nontreponemal tests for individuals with at least one nonreactive treponemal test and no reactive treponemal test were extracted from sexually transmitted disease (STD) surveillance systems in Florida and NYC from 2013 to 2017. Characteristics of individuals with BFPs were analyzed after selecting the observation with the highest titer from each individual. We next considered all results from individuals to characterize persons who had a 4-fold titer increase between successive nontreponemal tests. Among 526,540 reactive nontreponemal tests, there were 57,580 BFPs (11%) from 39,920 individuals. Over 90% (n = 52,330) of BFPs were low titer (≤1:4), but 654 (1%) were high-titer BFPs (≥1:32). Very high-titer (≥1:128) BFPs were more common among individuals over 60 years of age (odds ratio [OR], 2.68; 95% confidence interval [CI], 1.22 to 5.91). A 4-fold increase in titer was observed among 1,863 (14%) individuals with more than one reported BFP. Most BFPs detected by surveillance were low titer, but some were high titer and some had a 4-fold increase in titer. Review of patient histories might identify underlying conditions contributing to these high and rising titers.
Interfacing Plasmonic Nanoparticles with Ferroelectrics for Hot-Carrier-Driven Photocatalysis: Impact of Schottky Barrier Height

Emergent strategies for efficient solar energy conversion have focused on ways to harness photons in the lower-energy range of sunlight that cannot be utilized by conventional semiconductor photocatalyst systems. Recent research has demonstrated that interfaced plasmonic–ferroelectric particles represent a promising strategy for the utilization of near-infrared (NIR) light owing to the possibility of the more efficient injection of hot charge carriers from noble metal nanoparticles. Described herein, platinum-end-capped gold nanorods (AuNRs) function as antennae to absorb low-energy NIR photons to generate hot electrons that can be injected into ferroelectric PbZrxTi1–xO3 (PZT; x = 0.48, 0.50, 0.52, 0.54, 0.56, and 0.60) and drive the reduction of water to molecular hydrogen at its surfaces. As an aqueous suspension, the interfaced AuNR-PZT particles exhibited maximal photocatalytic rates for hydrogen formation under a 976 nm diode laser (powder density = 2.0 W cm–2) for the 52% Zr (x = 0.52) composition ...
A Cross-Sectional Analysis of Migraine-Related Disability in CADASIL: A Mayo Clinic Cohort

OBJECTIVES Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is inherited microangiopathy characterized by recurrent subcortical infarcts. A majority of those with CADASIL report coexistent migraine with aura. The authors aim to quantitatively describe migraine-related disability within a CADASIL cohort. METHODS A cross-sectional analysis was performed in a cohort of CADASIL. The Migraine Disability Assessment (MIDAS) quantified migraine-related disability. Further metrics obtained include first and last migraine, aura semiology, and therapeutic measures. RESULTS Twenty-four individuals were included [63% (15/24) female individuals; mean age, 56 y; range, 34 to 81 y]. Fifty-four percent (13/24) reported migraine, whereas 46% (11/24) reporting varying degrees of migraine-related disability. MIDAS Questionnaire scores appeared bimodal: 58% (14/24) scored 0 to 5, 7% (1/24) scored 6 to 10, 7% (1/24) scored 11 to 20 and 33% (8/24) scored over 20. Severe disability was associated with the multiplicity of aura semiologies and poor response to pharmacologic prophylaxis. CONCLUSIONS A bimodal distribution of migraine-related disability was observed. A third of individuals had a severe disability and appeared medically refractory to medical migraine prophylactic measures. This study may serve as a reference point for future trials quantitatively gauging response of novel migraine treatment strategies within this unique population.
Focused and defocused retinal images with Bessel and axicon pupil functions

Retinal image light distributions in a standard optical model of a diffraction-limited eye with round pupils are presented for several patterns of amplitude and phase modulation of the light admitted into the eye. Of special interest are circularly symmetrical configurations of truncated Bessel amplitude transmission functions, and of light subjected to axicon deviation. It is shown by several examples that this kind of beam shaping allows generation of retinal imagery, which can be more robust to defocus while maintaining minimal image degradation, and it points to situations of two separate zones simultaneously in sharp focus, several diopters apart.
The power of genres and the project of secularisation: publishing the Gesar epic in contemporary China

ABSTRACTThis article examines how published episodes from the life of Gesar—a king described in Tibetan epics—are assigned literary classifications inside and outside China. Outside of China, Tibet...
Death and serious injury from dark matter

Abstract Macroscopic dark matter (macros) refers to a class of dark matter candidates that scatter elastically off of ordinary matter with a large geometric cross-section. A wide range of macro masses M X and cross-sections σ X remain unprobed. We show that over a wide region within the unexplored parameter space, collisions of a macro with a human body would result in serious injury or death. We use the absence of such unexplained impacts with a well-monitored subset of the human population to exclude a region bounded by σ X > 10 − 8 − 10 − 7 cm2 and M X 50 kg. Our results open a new window on dark matter: the human body as a dark matter detector.
Linguistic Predictors of Problematic Drinking in Alcohol-related Facebook Posts.

Emerging adults often increase problematic drinking during college. Although they generally do not seek help for problematic drinking, college students discuss their drinking on social media. This ...
Comparison of active interrogation methods for source location in a scattering and absorbing medium, consisting of PGNAA, and an AmBe quasi-forward biased directional source.

ABSRACT Source location of Special Nuclear Material (SNM) encompassing 95% 235U and 239Pu is identified by utilizing a directional source from Patent No: US20190013109A1 using Prompt Gamma Neutron Activation Analysis (PGNAA) and neutron spectroscopy simulated with Monte-Carlo N-Particle transport 6.2 (MCNP). BC-408, HPGe, LaBr3 detector arrays were used to identify the location of the SNM using total counts incident on each detector, and PGNAA photopeaks from HPGe and LaBr3 detector arrays in a polyethylene shield. The conducted simulations varied the volume and location of the SNM in the MCNP input files to observe how the source location method behaved. PGNAA photopeaks used for source identification include 61 keV from fission, 2.223 MeV prompt gamma from hydrogen, 511 keV annihilation, and a single and double escape peaks from the prompt gamma interaction from hydrogen. The capabilities of each detector systems to acquire well resolved photopeaks with a 1% relative error or less, and total relative error for F4 and F8 tallies were less than 0.015% relative error. Source predictions of the SNM with uneven amounts of polyethylene shielding between the source and detectors was observed to overpredict and give invalid source location predictions. Source locations of the SNM with even amounts of polyethylene material between the source and each detector were found to be valid. With a 1 Ci 241Am source activity, it was determined that 1630 s were needed to obtain the results for each detector system with the quasi-forward directional AmBe source. Coupling source and material identification together would increase acquisition time but would only require one system to determine.
CS2 and the Impact of Programming Language Choice

There has been extensive research about the CS1 course. Much less has been written about the CS2 course, which is often a gateway course for CS majors. CS2 classes often reflect a second semester course in programming, yet when studying this course many universities have different purposes for this course. This poster shows the programming languages used in CS2 courses by the CS programs on the 28th Reid List of First Programing Languages. The languages used in CS1 and CS2 courses are discussed and the transitions between languages as students progress from their first course to their second. The analysis will then be discussed.
LAMC2 as a prognostic marker that promotes metastasis of lung adenocarcinoma through epithelial-mensenchymal transition (EMT).

11034 Background: Metastasis is the main cause of death in non-small cell lung cancer (NSCLC) patients. Genes responsible for NSCLC metastasis are unknown. LAMC2 is one of the 3 chains (α3, β3, γ2)...
Bi-literacy and motivation as predictors of bilingual students’ talk during classroom discussion

This study investigated the relations between bilingual students’ amount of talk during classroom discussion, motivation, and self-reported bi-literacy skills (i.e. reading, writing skills in their...
Opinion: Use science to stop sexual harassment in higher education.

Sexual harassment abounds in academia. We know this from a 2018 report published by the National Academies of Sciences, Engineering, and Medicine (1). As members of the committee who authored that report,* we have presented its findings to colleges and universities around the country. It has been deeply gratifying to see so many leaders want to address sexual harassment in their institutions. But according to a large body of social science evidence, the strategies that many of these same leaders are pursuing simply don’t work. Academia should lead and inspire change in other organizations. Instead, we have the highest rate of sexual harassment after the military (2). Several problems stand in the way of effective institutional response to sexual harassment: oversexualization of the problem, overreliance on fast fixes that fail to grapple with long histories of exclusion in the academy, and overemphasis on formal legal compliance. We need a radical redesign of anti-harassment efforts in higher education. This is a tall order, but decades of research can guide this work and brave leaders can implement it. The term “sexual harassment” is largely a misnomer. Most sexual harassment entails disrespect, not desire, and certainly not romance (3). There are the occasional come-ons: unwanted sexual advances, touches, kisses, or bribes and threats used to coerce sexual activity. But by far the most prevalent form of sexual harassment is the put-down, or what social scientists call gender harassment : comments, cartoons, jokes, gestures, and other insults to members of one sex/gender group (4, 5). Sometimes the put-downs are sexually degrading and crude, and other times they are contemptuous without sexual content. Women of color are likely to experience harassment that is based in both race and gender stereotypes (6). For lesbian, gay, bisexual, and transgender (LGBT) people, harassment often includes comments … [↵][1]1To whom correspondence may be addressed. Email: kclancy{at}illinois.edu. [1]: #xref-corresp-1-1
Energetics and mechanisms for decomposition of cationized amino acids and peptides explored using guided ion beam tandem mass spectrometry

Fragmentation studies of cationized amino acids and small peptides as studied using guided ion beam tandem mass spectrometry (GIBMS) are reviewed. After a brief examination of the key attributes of the GIBMS approach, results for a variety of systems are examined, compared, and contrasted. Cationization of amino acids, diglycine, and triglycine with alkali cations generally leads to dissociations in which the intact biomolecule is lost. Exceptions include most lithiated species as well as a few examples for sodiated and one example for potassiated species. Like the lithiated species, cationization by protons leads to numerous dissociation channels. Results for protonated glycine, cysteine, asparagine, diglycine, and a series of tripeptides are reviewed, along with the thermodynamic consequences that can be gleaned. Finally, the important physiological process of the deamidation of asparagine (Asn) residues is explored by the comparison of five dipeptides in which the C-terminal partner (AsnXxx) is altered. The GIBMS thermochemistry is shown to correlate well with kinetic results from solution phase studies.
Involvement of calcium in the mevalonate-accelerated degradation of 3-hydroxy-3-methylglutaryl-CoA reductase.

3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), the rate-limiting enzyme in the biosynthesis of cholesterol and isoprenoids, is subject to rapid degradation which is regulated by mevalonate (MVA)-derived metabolic products. HMG-CoA reductase is an integral membrane protein of the endoplasmic reticulum, the largest nonmitochondrial pool of cellular Ca2+. To assess the possible role of Ca2+ in the regulated degradation of HMG-CoA reductase, we perturbed cellular Ca2+ concentration and followed the fate of HMG-CoA reductase and of HMGal, a fusion protein consisting of the membrane domain of HMG-CoA reductase and the soluble bacterial enzyme beta-galactosidase. The degradation of HMGal mirrors that of HMG-CoA reductase, demonstrating that the membrane domain of HMG-CoA reductase is sufficient to confer regulated degradation (Skalnik, D.G., Narita, H., Kent, C., and Simoni, R.D. (1988) J. Biol. Chem. 263, 6836-6841; Chun, K.T., Bar-Nun, S., and Simoni, R.D. (1990) J. Biol. Chem. 265, 22004-22010). In this study we show that the MVA-dependent accelerated rates of degradation of HMG-CoA reductase and HMGal in cells maintained in Ca(2+)-free medium are 2-3-fold slower than the rate of degradation in cells grown in high (1.8-2 mM) Ca2+ concentration. This effect is reversed upon addition of Ca2+ to the medium. Furthermore, when cells maintained in high Ca2+ are treated with 1 microM ionomycin, the MVA-dependent accelerated degradation of HMG-CoA reductase and HMGal is also reduced about 2-3-fold. This inhibition is not due to a Ca(2+)-dependent uptake or incorporation of MVA into sterols, since these processes are not affected in the absence of external Ca2+. In addition, cobalt, a known antagonist of Ca(2+)-dependent cellular functions, totally abolishes (IC50 = 520 microM in the presence of 1.8 mM extracellular Ca2+) the MVA-accelerated degradation of HMGal. These results suggest that Ca2+ plays a major role in the regulated degradation of HMG-CoA reductase.
Optimal Capacity Expansion with Off-Design Costs

The effect of “off-design” operating costs on operating and capacity expansion policy is considered for the planning of a water treatment facility. A mixed-integer programming model is presented for minimizing discounted costs of dynamically expanding a reverse-osmosis process that is required to remove increasing levels of salt over time from a brackish stream. Several possible product effluent qualities are considered as variables in the model. Results show the explicit consideration of off-design operating costs can influence capacity expansion planning and reduce actual system costs by a small percentage for desalting facilities. This (apparently small) percentage saving could amount to significant absolute savings in multimillion dollar projects. Analogous percentage savings in other process planning (e.g., municipal water and wastewater treatment, and power generation) could be more or less significant depending on relationship of design to off-design generating costs.
Nanophotonic metastructures: Functionality at the extreme

We have been exploring the light-matter interaction in metastructures with scenarios that include extreme dimensionality, processing at nanoscales, extreme parameter values, unusual topology, and extreme near zones. We give an overview of our ongoing study.
Throughput analysis of selective repeat ARQ combined with adaptive modulation for fading channels

We mainly investigate how a selective-repeat automatic repeat request (SR-ARQ) scheme works when it is used with an adaptive modulation system (AMS). Simple analytical expressions for the throughput performance of the SR-ARQ/AMS are presented. We obtain the throughput performance of a SR-ARQ/AMS for various fading channels. We also consider channel estimation errors for the throughput analysis and compare the throughput performance with that when perfect channel estimation is assumed. Numerical results from the analysis show that the throughput performance of a SR-ARQ/AMS outperforms that of a conventional SR-ARQ when used with a fixed modulation system.
Export production and its regulating factors in the West Antarctica Peninsula region of the Southern Ocean

[1] In connection with the Palmer LTER program, mixed layer water samples were collected during the cruise of the L.M. Gould in Jan., 2008 at 49 stations on a 20 × 100 km grid in the West Antarctica Peninsula (WAP) region of the Southern Ocean. In this study, [O2]/[Ar] ratios and the triple isotope composition of dissolved O2 were measured, and were used to estimate net community O2 production (NCP) and gross primary O2production (GPP), respectively. These estimates are further converted to carbon export production, primary production and the f-ratio. Our measurements give NCP ranging from −3 to 76 mmol O2 m−2 day−1 (−25 to 650 mg C m−2 day−1), and GPP from 40 to 220 mmol O2 m−2 day−1 (180 to 1010 mg C m−2 day−1). The O2 NCP/GPP ratios range from −0.04 to 0.43, corresponding to f-ratios of −0.08 to 0.83. NCP and the NCP/GPP ratio are highest in the northern coastal areas, and decrease to lower values toward the southern coastal area and the open ocean. The inshore-offshore gradient appears to be regulated primarily by iron availability, as supported by the positive correlation between NCP and Fv/Fm ratios (r2 = 0.22, p < 0.05). Mixed layer depth (MLD) is inversely correlated with NCP (r2 = 0.21, p < 0.002) and NCP/GPP (r2 = 0.21, p < 0.02), and highest NCP occurred in the fresh water lenses probably formed from melted coastal glaciers. These results suggest that export production and the f-ratio increase where water stratification is intensified by input of fresh meltwater, and that mixed layer stratification is the major factor regulating NCP in the inner-shelf and coastal regions. Along-shelf variability of phytoplankton community composition is highly correlated with NCP, i.e., NCP increases when the diatom-dominated community in the south transitions to the cryptophyte-dominated one in the north. A high correlation is also observed between NCP and the logarithm of the surface chlorophyll concentration (r2 = 0.72, p < 0.0001) , which makes it possible to estimate carbon export as a function of Chl a concentration in this region.
The H3K4-Methyl Epigenome Regulates Leukemia Stem Cell Oncogenic Potential

The genetic programs that maintain leukemia stem cell (LSC) self-renewal and oncogenic potential have been well defined; however, the comprehensive epigenetic landscape that sustains LSC cellular identity and functionality is less well established. We report that LSCs in MLL-associated leukemia reside in an epigenetic state of relative genome-wide high-level H3K4me3 and low-level H3K79me2. LSC differentiation is associated with reversal of these broad epigenetic profiles, with concomitant downregulation of crucial MLL target genes and the LSC maintenance transcriptional program that is driven by the loss of H3K4me3, but not H3K79me2. The H3K4-specific demethylase KDM5B negatively regulates leukemogenesis in murine and human MLL-rearranged AML cells, demonstrating a crucial role for the H3K4 global methylome in determining LSC fate.
Chronic hyponatremia reduces survival of magnocellular vasopressin and oxytocin neurons after axonal injury

Axonal injury to hypothalamic magnocellular vasopressin (AVP) and oxytocin (OT) neurons causes degeneration of a substantial subpopulation of these neurons. In this study, we investigated the influence of osmolality on this injury-induced cell death. Normonatremic, chronically hypernatremic, and chronically hyponatremic rats received pituitary stalk compression (SC), which causes degeneration of AVP and OT terminals in the neurohypophysis. Twenty-one days after SC, rats were perfused and hypothalami were serially sectioned and alternately stained for AVP-neurophysin and OT-neurophysin immunoreactivities. Normonatremic and hypernatremic rats exhibited a triphasic pattern of water intake after SC, with peak intakes 3 times higher than those exhibited by sham-operated normonatremic rats. In contrast, hyponatremic SC rats exhibited peak water intakes of 600 ml/24 hr, approximately 9-10 times the water intakes of sham-operated normonatremic rats. In normonatremic rats, SC caused degeneration of 65% of the AVP neuron population in the SON and 73% in the PVN, but only 31% of the OT neuron population in the SON and 35% in the PVN. Similar results were found in hypernatremic rats after SC. However, in hyponatremic rats SC caused degeneration of 97% of the AVP neuron population in the SON and 93% in the PVN, and 90% of the OT neuron population in the SON and 84% in the PVN. Our results, therefore, demonstrate that injury-induced degeneration of magnocellular AVP and OT neurons is markedly exacerbated by chronic hypo-osmolar conditions, but neuronal survival is not enhanced by chronic hyperosmolar conditions.
Encyclopedia of National Dress: Traditional Clothing around the World

The Encyclopedia of National Dress: Traditional Clothing around the World is a wonderful addition to the study of cultures and peoples around the world through their clothing and styles of traditio...
Mutant p53 and aberrant cytosine methylation cooperate to silence gene expression

p53 is an important transcriptional regulator that is frequently mutated in cancer. Gene-profiling experiments of breast cancer cells infected with wt p53 revealed both MASPIN and desmocollin 3 (DSC3) to be p53-target genes, even though both genes are silenced in association with aberrant cytosine methylation of their promoters. Despite the transcriptional repression of these genes by aberrant DNA methylation, restoration of p53 resulted in the partial reactivation of both genes. This reactivation is a result of wt p53 binding to its consensus DNA-binding sites within the MASPIN and DSC3 promoters, stimulating histone acetylation, and enhancing chromatin accessibility of their promoters. Interestingly, wt p53 alone did not affect the methylation status of either promoter, suggesting that p53 itself can partially overcome the repressive barrier of DNA methylation. Pharmacologic inhibition of DNA methylation with 5-aza-2'-deoxycytidine in combination with restoration of wt p53 status resulted in a synergistic reactivation of these genes to near-normal levels. These results suggest that cancer treatments that target both genetic and epigenetic facets of gene regulation may be a useful strategy towards the therapeutic transcriptional reprogramming of cancer cells.
Phenomenological model of longitudinal spin fluctuations in itinerant antiferromagnets

We present the phenomenological analysis of the spectrum of longitudinal spin fluctuations in isotropic itinerant electron antiferromagnets with account of spin anharmonicity giving rise to coupling of transverse and longitudinal normal modes. The spectrum consists of a quasielastic part forming a central peak or a dip, depending on temperature and the Landau relaxation rate. Effects of spin-fluctuation coupling also give rise to an inelastic part of the spectrum which has a form of resonances or antiresonances near the magnon frequencies related to nonpropagating longitudinal excitations.
Structural constitutive characterization of the vocal fold: Modeling the fibrous and the interstitial matrix proteins

The extracellular matrix (ECM) of the human vocal fold is a highly specialized soft connective tissue with a layered microstructure that is optimally tuned for vibration and sound production in response to a unique set of biomechanical stimuli in vivo, including oscillation at amplitudes up to 3–4 mm at magnitudes of acceleration > 200g and at high frequencies (> 100Hz). The vocal fold ECM, commonly called the lamina propria or mucosa, consists of biomacromolecules of two major classes distributed in different densities: (1) fibrous proteins including collagen and elastin fibers that are denser in the deep layers of the ECM, and (2) interstitial proteins like glycosaminoglycans and structural glycoproteins that are scattered throughout the entire ECM [1,2]. Nonlinear viscoelastic response of the vocal fold ECM under different loading conditions has been reported, including strain rate-dependence and hysteresis of tensile stress-strain curves, and nonlinear stress-strain behavior under large-strain shear [3,4].Copyright © 2004 by ASME
The remote sensing of suspended sediment concentrations of small impoundments

The suspended sediment concentrations of 14 Oklahoma impoundments were related to bands of reflected light as measured from an aircraft-borne multispectral scanner. Suspended sediment concentrations (Y) were curvilinearly related to reflectance (X) where the exponent onX exceeds one. The best relationships, upon consideration of sensitivity, range, and precision, appeared in the bands defined by 588 to 643 and 650 to 690 nm wavelength. The latter was less precise. The measured range in sediment concentration was 13 to 232 mg l−1
Dynamic measurement of the J integral in ductile metals: Comparison of experimental and numerical techniques

Experiments and analyses designed to develop an extension of the method of caustics to applications in dynamic, elastic-plastic fracture mechanics are described. A relation between the caustic diameter, D, and the value of the J integral was obtained experimentally and numerically for a particular statically loaded specimen geometry (three point bend) and material (4340 steel). Specimens of the same geometry and material were then loaded dynamically in impact. The resulting caustics, recorded using high speed photography, were analyzed on the basis of the J versus D relation to determine the time history of the dynamic value of J, J d (t). The history of J d thus obtained is compared with good agreement to an independent determination of J d (t) based on a two-dimensional, dynamic, elastic—plastic finite element analysis, which used the experimentally measured loads as traction boundary conditions.
Flaser and wavy bedding in ephemeral streams: a modern and an ancient example

Abstract Flaser and wavy bedding are sedimentary structures characterized by alternating rippled sand and mud layers. These structures often are considered to form mostly in tidally influenced environments; published examples from fluvial environments are rare. Flaser and wavy bedding were found in two ephemeral stream deposits: the Jurassic Kayenta Formation and the modern wash in Seven Mile Canyon, both located in southeastern Utah, USA. These examples demonstrate that flaser bedding can form and be preserved in ephemeral streams.
Bayesian ordinal and binary regression models with a parametric family of mixture links

An ordinal and binary regression model with parametric link is introduced. The link is a member of a one-parameter family of “mixture links”, a family that comprises smooth mixtures of the extreme minimum-value, extreme maximum-value, and logistic distributions. A Bayesian version of this flexible model serves as a vehicle for introducing a priori information regarding the choice of link. Owing to non-conjugacy, posterior and predictive distributions are approximated using Markov chain Monte Carlo simulation methods. Link-independent, Bayesian interpretations of covariate effects are described. The method is illustrated through the analyses of several data sets.
Mechanism and Regulation of Urea Permeation in a Mammalian Urea Channel

To maintain constant fluid volume and osmolarity in the face of infrequent access to water, terrestrial animals accumulate high concentrations of urea in the kidney interstitium to allow the reabsorption of water. This mechanism is dependent on the facilitated diffusion of urea through members of a family of integral membrane proteins known as urea transporters (UTs). While the structure of a bacterial homolog was solved previously, the bacterial UT transports urea much slower than the mammalian ones and its similarity to the mammalian proteins remained unclear. In addition, little was known of the mechanism of permeation. To answer these questions, we have solved the first structure of a mammalian urea transporter at 2.4 A, and probed the energetics of urea permeation with a combination of molecular dynamics simulations, functional characterization of mutants and co-crystallization with urea analogs. Similarities with the bacterial UT suggest that many features of the structure are broadly conserved across the UT family, including a trimeric assembly, and the presence of a channel-like, continuous permeation pathway through each monomer. The functional and computational studies revealed a large energy barrier at the center of the permeation pathway, whose presence may hint towards a possible gating mechanism.
Tests for Two-Body Quantum-Chromodynamic Subprocesses in Dilepton Angular Correlations.

Angular distributions for dileptons formed in hadronic collisions at large mass ${Q}^{2}$ and large transverse momentum ${Q}_{t}$ are calculated, assuming various two-body quantum chromodynamic subprocesses. The main results are the following: (a) The polar and azimuthal distributions are correlated. (b) For fixed ${{Q}_{t}}^{2}$, the distributions scale in the variable $w=\frac{{{Q}_{t}}^{2}}{{Q}^{2}}$, and thus are independent of total energy. (c) Each subprocess exhibits a characteristic function of $w$, independent of the constituent distributions.
Neurotransmitter systems of the medial prefrontal cortex: potential role in sensitization to psychostimulants.

The mesocorticolimbic dopamine system, which arises in the ventral tegmental area and innervates the nucleus accumbens, among numerous other regions, has been implicated in processes associated with drug addiction, including behavioral sensitization. Behavioral sensitization is the enhanced motor-stimulant response that occurs with repeated exposure to psychostimulants. The medial prefrontal cortex (mPFC), defined as the cortical region that has a reciprocal innervation with the mediodorsal nucleus of the thalamus, is also a terminal region of the mesocorticolimbic dopamine system. The mPFC contains pyramidal glutamatergic neurons that serve as the primary output of this region. These pyramidal neurons are modulated by numerous neurotransmitter systems, including γ-aminobutyric acidergic interneurons and dopaminergic, noradrenergic, serotonergic, glutamatergic, cholinergic and peptidergic afferents. Changes in interactions between these various neurotransmitter systems in the mPFC may lead to alterations in behavioral responses. For example, recent studies have demonstrated a role for decreased mPFC dopaminergic transmission in the development of psychostimulant-induced behavioral sensitization. The present review will discuss the anatomical organization of the mPFC including descriptions of innervation patterns and receptor localization of the various neurotransmitter systems of this region. Data supporting or suggesting a role for each of these mPFC transmitter systems in the development of behavioral sensitization to cocaine and amphetamine will be presented. Finally a model of the mPFC that may be useful in directing future research efforts on the cortical mechanisms involved in the development of sensitization will be proposed.
The implanted defibrillator: relation of defibrillating lead configuration and clinical variables to defibrillation threshold

Forty-two defibrillating lead systems for the automatic implantable defibrillator were implanted and tested in 41 patients. Two basic lead configurations were used: 1) spring-patch, consisting of a transvenous superior vena cava spring electrode as the anode and an apical or left lateral ventricular patch electrode (either small [13.9 cm2] or large [27.9 cm2]) as the cathode; and 2) patchpatch, consisting of an anterior right ventricular patch as the anode and a posterior left ventricular patch as the cathode. Of the 42 lead systems, 10 were springpatch and 32 were patch-patch combinations. The defibrillation threshold for the patch-patch combinations (9.8 ± 6.5 J, mean ± standard deviation) was significantly (p Analysis of the relation of clinical variables to defibrillation threshold revealed that only amiodarone therapy was independently associated with a significantly (p
Least squares regression vs. geometric mean regression for ecotoxicology studies

Least squares linear regression and geometric mean regression analysis procedures are compared for use in analyzing ecotoxicology data. These data are characterized by both response data and environmental factor data being measured with error. According to cited literature, when factor data are measured with error, regression analyses for response as a function of environmental factors should be performed using geometric mean regression. A case is made in the current paper that it is more appropriate to use least squares regression in analyses of such data rather than geometric mean regression.
A device model for the amorphous-silicon staggered-electrode thin-film transistor

A model for the amorphous-silicon (a-Si) staggered-electrode thin-film transistor (TFT) that incorporates gate-voltage dependent mobility for channel current and space-charge-limited current effects for the source and drain contacts is discussed. This model is in excellent agreement with TFT data over a wide range of applied voltages and for various channel lengths. For the devices measured, the TFT current depends more sensitively on effective channel mobility than on space-charge-limited current through the a-Si layer, but the latter is responsible for current crowding at low drain voltage. Because of the two-dimensional current flow under the contacts, their equivalent lumped element model exhibits a different power law behaviour than that for one-dimensional current flow in an n/sup +/-i-n/sup +/ structure. It also shows that a peak in the differential conductance curve at low drain voltage is a sensitive indicator of current crowding and implies a superlinear equivalent lumped element in series with the intrinsic TFT. >
Modeling of compact explosively-driven ferroelectric generators

Hydrodynamic pressure simulations combined with an empirical algorithm are used to model the open-circuit voltage output of several explosively compressed ferroelectric materials. The empirical algorithm was initially developed using detonating cord containing PETN and a metal driver element to compress the ferroelectric materials while the open-circuit voltage is recorded. A hydrodynamic code suite, CTH from Sandia National Labs, enables calculating shockwave propagation and localized pressures. The resulting pressure profile in the ferroelectric material is then used as input for an empirically derived algorithm to calculate the predicted open-circuit voltage of the ferroelectric material. This previously developed empirical algorithm exhibited reasonable correlation between experimental and calculated open-circuit output voltages, but began to deviate when more powerful explosives were used. Hence, the amount of explosive material and geometry of the metal drive was varied to produce a wide range of peak pressures, including pressures higher then the maximum of 3.1 GPa previously modeled by the empirical algorithm. This data serves as the base to further develop the empirical algorithm for various ferroelectric materials and to more accurately model the open-circuit output voltage (experimentally observed range, normalized for thickness, of 1.3 to 3.8 kV/mm) over the wide range of applied pressures.
Euler’s Contributions to Mathematics Useful in Statistics

An enormously productive 18th century mathematician, Euler made a number of wide-ranging advances that remain useful in statistics. These include beta and gamma functions, summation of infinite series, calculus of variations, Euler’s phi-function, Latin and Graeco-Latin squares, and generating functions. All these are outlined and illustrated in this article.
Length of Maternity Leave and Quality of Mother-Infant Interactions.

The aim of this study was to assess the association between the length of maternity leave and the quality of mother-infant interactions; 198 employed mothers of 4-month-old infants were interviewed and videotaped in their homes during a feeding time. Hierarchical multiple regression analyses indicated a direct association between shorter length of leave and more negative affect and behavior in maternal interactions with their infants. Infant and mother stressor/protective variables added significantly in predicting the quality of the mother-infant relationship. There were also significant interaction effects between the length of leave and these variables. Mothers who either reported more depressive symptoms or who perceived their infant as having a more difficult temperament and who had shorter leaves, compared with mothers who had longer leaves, were observed to express less positive affect, sensitivity, and responsiveness in interactions with their infants. The public policy implications of the relation between length of maternity leave, maternal and infant individual differences, and the quality of mother-infant interactions are discussed.
Forced expression of the tumor suppressor adenomatosis polyposis coli protein induces disordered cell migration in the intestinal epithelium.

Abstract Mutations of the human adenomatosis polyposis coli (APC) gene are associated with the development of familial as well as sporadic intestinal neoplasia. To examine the in vivo function of APC, 129/Sv embryonic stem (ES) cells were transfected with DNA encoding the wild-type human protein under the control of a promoter that is active in all four of the small intestine's principal epithelial lineages during their migration-associated differentiation. ES-APC cells were then introduced into C57BL/6-ROSA26 blastocysts. Analyses of adult B6-ROSA26 129/Sv-APC chimeric mice revealed that forced expression of APC results in markedly disordered cell migration. When compared with the effects of forced expression of E-cadherin, the data suggest that APC-catenin and E-cadherin-catenin complexes have opposing effects on intestinal epithelial cell movement/adhesiveness; augmentation of E-cadherin-beta-catenin complexes produces a highly ordered, "adhesive" migration, whereas augmentation of APC-beta-catenin complexes produces a disordered, nonadhesive migratory phenotype. We propose that APC mutations may promote tumorigenesis by increasing the relative activity of cadherin-catenin complexes, resulting in enhanced adhesiveness and functional anchorage of initiated cells within the intestinal crypt. Our studies also indicate that chimeric mice generated from B6-ROSA26 blastocysts and genetically manipulated ES cells should be useful for auditing gene function in the gastrointestinal tract and in other tissues.
Damage evaluation of prestressed piles to cast in place bent cap connections with Acoustic Emission

Abstract Acoustic Emission has progressed rapidly as a method for damage evaluation in civil structures. For these purposes several damage evaluation techniques which are able to supply an engineer with information regarding structural integrity have been developed. In this work Acoustic Emission data is taken from five full-scale single pile to bent cap connection specimens. Specimens were tested in a laboratory environment and subjected to cyclic displacements. This data is used to evaluate the damage classification chart which results from plotting calm and load ratios. Various methods of calm ratio calculation are investigated. A new method of damage classification based on the calculation of these parameters is presented. Data from tested specimen is also used in the development of a damage classification chart using intensity analysis. This chart is used to evaluate damage occurring in a full-scale three-pile specimen subjected to representative seismic loading. Results show that under different conditions the chart is able to accurately assess the amount of damage occurring within the specimen. These results represent a step toward field implementation of the technique. Damage evaluation is also performed and validated using cumulative AE energy. The method previously applied to conventionally reinforced concrete members proves to accurately assess damage occurring in prestressed members.
Deformation and stress in PMMA during hard x-ray exposure for deep lithography

The availability of high-energy, high-flux, collimated synchrotrons radiation has extended the application of deep X-ray lithography (DXRL) to thickness values of the PMMA resist of several millimeters. Some of the most severe limitations come from plastic deformation, stress, and cracks induced in PMMA during exposure and development. We have observed and characterized these phenomena quantitatively. Profilometry measurements revealed that the PMMA is subjected either to local shrinkage or to expansion, while compression and expansion evolve over time. Due to material loss and crosslinking, the material undergoes a shrinkage, while the radiation-induced decomposition generates gases expanding the polymer matrix. The overall dynamics of the material microrelief and stress during and after the exposure depend on the balance between compaction and outgassing. These depend in turn on the exposure conditions (spectrum; dose, dose rate, seaming, temperature), post-exposure storage conditions, PMMA material properties and thickness, and also on the size and geometry of the exposed patterns.