cssi/SciSciGPT-SciSciNet huggingface dataset:
SpaceCube v2.0 space flight hybrid reconfigurable data processing system

This paper details the design architecture, design methodology, and the advantages of the SpaceCube v2.0 high performance data processing system for space applications. The purpose in building the SpaceCube v2.0 system is to create a superior high performance, reconfigurable, hybrid data processing system that can be used in a multitude of applications including those that require a radiation hardened and reliable solution. The SpaceCube v2.0 system leverages seven years of board design, avionics systems design, and space flight application experiences. This paper shows how SpaceCube v2.0 solves the increasing computing demands of space data processing applications that cannot be attained with a standalone processor approach.
Reconstruction of the spectral type of limiting distributions in dynamical conflict systems

We establish the conditions of reconstruction of pure spectral types (pure point, pure absolutely continuous, or pure singularly continuous spectra) in the limiting distributions of dynamical systems with compositions of alternative conflict. In particular, it is shown that the point spectrum can be reconstructed starting from the states with pure singularly continuous spectra.
Angiotensin II increases vascular proteoglycan content preceding and contributing to atherosclerosis development

Angiotensin II (angII) is known to promote atherosclerosis; however, the mechanisms involved are not fully understood. To determine whether angII stimulates proteoglycan production and LDL retention, LDL receptor-deficient mice were infused with angII (1,000 ng/kg/min) or saline via osmotic minipumps. To control for the hypertensive effect of angII, a parallel group received norepinephrine (NE; 5.6 mg/kg/day). Arterial lipid accumulation was evaluated by measuring the retention rate of LDL in isolated carotid arteries perfused ex vivo. Mice infused with angII had increased vascular content of biglycan and perlecan and retained twice as much LDL as saline- or NE-infused mice, although no group developed atherosclerosis at this time. To determine whether this increase in biglycan and perlecan content predisposed to atherosclerosis development, mice were infused with angII, saline, or NE for 4 weeks, then pumps were removed and mice received an atherogenic Western diet for another 6 weeks. Mice that had received angII infusions had 3-fold increased atherosclerosis compared with mice that had received saline or NE, and apolipoprotein B colocalized with both proteoglycans. Thus, one mechanism by which angII promotes atherosclerosis is increased proteoglycan synthesis and increased arterial LDL retention, which precedes and contributes to atherosclerosis development.
Real‐Time Monitoring of Luminal Esophageal Temperature During Left Atrial Radiofrequency Catheter Ablation for Atrial Fibrillation: Observations About Esophageal Heating During Ablation at the Pulmonary Vein Ostia and Posterior Left Atrium

Introduction: Left atrial radiofrequency catheter ablation (RFA) is gaining acceptance as treatment for drug-refractory atrial fibrillation (AF). This therapy has been associated with esophageal injury and atrioesophageal fistula formation causing death. Methods: We describe 3 patients undergoing catheter ablation for AF during real-time monitoring of luminal esophageal temperature. Results: We observed heating of the esophagus during short duration low power RFA, at either the left or right pulmonary vein ostia. Cryoablation at the pulmonary vein ostium in one patient resulted in esophageal cooling. Furthermore, we observed that fluoroscopic localization of the ablation catheter at a site apparently distant from the esophagus is not adequate to assure avoidance of ablation-induced esophageal heating. Conclusions: Real-time monitoring of luminal esophageal position and temperature is feasible, enhances recognition of esophageal heating, and may add useful information beyond that provided by fluoroscopic assessment of esophageal position. There is a potential role for esophageal monitoring to help avoid thermal injury to the esophagus during catheter ablation for atrial fibrillation.
Comparing Formal and Informal Lobbying Practices in China The Capital's Ambivalent Embrace of Capitalists

The marketization of China's economy and the attendant need for a supporting regulatory framework have resulted in extensive lobbying by Chinese and foreign industry. The central party-state has adopted an ambivalent posture toward this development. On the one hand, the government has encouraged the development of industry associations, public hearings, and comment-and-response periods for draft laws and regulations to routinize public policy consultations. On the other hand, the central party-state is deeply concerned about the political consequences of permitting greater social activism, and hence, it continues to constrain the maturation of these same formal institutions and processes. As a consequence, informal lobbying practices, such as direct lobbying and manipulation of the media, have become more prominent vehicles for industry involvement in the policy process.
A probabilistic neural network approach for modelling and classifying efficiency of GCC banks

Understanding the efficiency levels is crucial for understanding the competitive structure of a market and/or segments of a market. This study uses two artificial Neural Networks (NN) and a traditional statistical classification method to model and classify the relative efficiency of top Gulf Cooperation Council (GCC) banks. Accuracy indices are used to assess the classification accuracy of the models. Results indicate that the predictive accuracy of NN models is quite similar to that of traditional statistical methods. The study shows that the NN models have a great potential for the classification of banks' relative efficiency due to their robustness and flexibility of modelling algorithms. The implications of these results for potential efficiency programmes are discussed.
Factors associated with periodontitis in an HIV-infected southeast USA study.

OBJECTIVES: To determine the relationship of immunosuppression with measures of probing pocket depth (PPD), recession (REC), and clinical attachment level (CAL) in an HIV-infected population from North Carolina (NC), a state in the southeastern United States (USA). DESIGN: Cross-sectional study of HIV-infected adults (n = 326) treated at the University of North Carolina Hospitals. Clinical medical record review and sociodemographic interview data were collected. Median age of study participants was 37 years (range 19-67). Males comprised 78% and Blacks 60%. Analyses were limited to those who were dentate (n = 316). MAIN OUTCOME MEASURES: Main outcomes were cases vs non-cases of notable PPD, REC, and CAL. Immunosuppression measured by CD4 + cell count μL was the exposure of interest. RESULTS: Defined cases of PPD (n = 148) were 2.6 (95% CI = 1.3, 5.3) times less likely to occur at CD4 + cells <200 than non-cases, whereas, cases of REC (n = 94) were 2.8 (95% Cl = 1.2, 6.6) times more likely to occur at that level of severe immunosuppression, controlling for confounders. CONCLUSION: Sub-groups of persons with HIV experience a high burden of periodontitis where notable severity and extent of PPD, CAL, and REC were clearly evident at different stages of immunosuppression.
On the Proposed Sexual and Gender Identity Diagnoses for DSM-5: History and Controversies

In February, 2010, the American Psychiatric Association unveiled its proposed revisions to the Sexual and Gender Identity Disorders for the fifth edition of its Diagnostic and Statistical Manual of Mental Disorders (DSM-5). The proposals have reinvigorated historical controversies about whether sexual and gender diagnoses may stigmatize and medicalize behaviors that are now considered nonpathological. This article traces the recent past of these controversies, beginning with early discourse about the future DSM-5. It addresses the content of the DSM-5's proposed changes to Gender Identity Disorder (GID) and the paraphilias, outlining responses to them in mental health and activist communities. Points of contention surrounding the recent proposals are assessed within the context of historical concerns. Additionally, my opinion regarding the potential of the DSM-5 proposals to assuage versus exacerbate longstanding controversies is presented.
Naloxone induces copulation in control but not in prenatally stressed male rats

Pregnant rats were subjected to environmental stress (immobilization, illumination, heat) during the last trimester of gestation. Copulatory behavior of prenatally stressed and control male offspring was determined during seven weekly 30-min tests. At the conclusion of the 7-week testing period, prenatally stressed and control males that were sexually inactive were injected intraperitoneally with 10 mg/kg of naloxone hydrochloride 30-min prior to retesting for copulatory behavior. Fifty-five percent (10/18) of the control males became sexually active and ejaculated during a single 30-min testing period, whereas 0% (0/32) of the prenatally stressed males became sexually active. It is concluded that prenatal stress renders male offspring unresponsive to opiate-antagonist induction of copulatory behavior.
Policy Implications of a Water Quality-constrained Dynamic Model of Nitrogen Fertilizer Use

Summary This paper has demonstrated that the omission of a time lag associated with contaminant transport processes will result in sub-optimal nitrogen fertilizer use by, first, presenting a surface and groundwater quality-constrained dynamic optimization model of nitrogen fertilizer use. Potential groundwater contamination has been presented in a probabilistic manner, with the probability of contaminant level exceeding the MCL. Second, we have discussed the economic effects of fiscal programs including a user tax and a unit subsidy for the reduction of nitrogen fertilizer use. We have highlighted that the introduction of a unit subsidy program via redeemable coupons transforms the fertilizer market into a market characterized by perceived imperfect competition, and the government subsidy expenditure under imperfect competition is greater than under perfect competition. Therefore, directly incorporating water quality-constraints, and accounting for perceived imperfect competition results in a better understanding of the impacts of government policy.
Membrane performance requirements for carbon dioxide capture using hydrogen-selective membranes in integrated gasification combined cycle (IGCC) power plants

Precombustion CO2 capture is an important option for the management of greenhouse gas emissions from power generation, because the higher concentrations can lead to improved separation economics. Membranes can provide a significant boost in the performance by separating CO2 at high temperature and at high pressure, provided they are properly integrated into a power plant. In this study, membrane performance targets were derived for CO2 capture using H2-selective membranes in integrated gasification combined cycle (IGCC) power plant systems. Three key differences were found relative to plants configured for the production of industrial-grade H2. First, the H2/CO2 selectivity requirement is lower when the permeate is combusted in a gas turbine, as opposed to purified for industrial use. Second, the membrane is subject to additional selectivity requirements. For example, CO2 product purity specs impose a H2/N2 selectivity requirement. Third, the plant design must account for the energy associated with unshifted CO, CH4 and other fuel components that are not separated by the membrane. In contrast to H2 production systems where the high H2/CO2 selectivity requirement favors ultra-high selectivity metal-based membranes, the requirements for IGCC indicate a wider range of materials, including ceramic, zeolite, and polymeric membranes, should be considered.
Enhanced esterolytic activities of several derivatives of polyethyleneimine

Abstract Mercaptoethylation of polyethyleneimine introduces nucleophilic -SH groups into the polymer. Rates of esterolysis of nitrophenyl esters in the presence of such polymer derivatives show increases of 2–3 orders of magnitude.
Negative-U defect: Interstitial boron in silicon.

Novel optical deep-level-transient-spectroscopy (DLTS) studies are reported which reveal a new level (the single-donor level) of interstitial boron in silicon located at ${E}_{c}$-(0.13\ifmmode\pm\else\textpm\fi{}0.01) eV. Detailed studies of this level and the previously detected single-acceptor level at ${E}_{c}$-(0.37\ifmmode\pm\else\textpm\fi{}0.08) eV establish that these levels lie in negative-U ordering. A large Poole-Frenkel effect in the DLTS observed emission rate is apparent, and when properly accounted for provides a direct and unambiguous connection to the EPR-identified interstitial boron atom.
Atriovenous Nodal Function in the Immature Canine Heart

ABSTRACT. Previous studies have suggested that the atriovenous nodal functional refractory period in the neonate is equal to or shorter than that of the ventricle, providing little or no protection to the ventricle against rapid atrial rates and allowing closely coupled atrial beats to fall within the ventricular vulnerable period. We evaluated atriovenous node function in 21 mongrel neonatal puppies, 3-15 days old, and 15 adult dogs utilizing intracardiac His bundle recording and stimulation techniques. The mean atriovenous nodal functional refractory period (173.1 ± 20.0 ms) exceeded both the ventricular effective refractory period (139.5 ± 14.3) and ventricular functional refractory period (163.3 ± 14.5) in the neonates. Furthermore, the atriovenous node was the site of limiting antegrade conduction in all neonates. No ventricular arrhythmias were induced by atrial extrastimulation in any of the neonates. The site of conduction delay during atrial extrastimulation was confined to the atriovenous node in 15/16 neonates (94%) while 1/16 (6%) had combined nodal and infranodal delay. The neonates developed Wenckebach, at significantly faster heart rates than the adults, but both groups developed Wenckebach at approximately twice the resting heart rate. Retrograde conduction was a consistent finding in the neonates. However, antegrade Wenckebach occurred at a significantly faster heart rate than retrograde Wenckebach suggesting different functional properties. Our data suggest that in the neonatal canine, the atriovenous node functional refractory period is longer than both the ventricular effective refractory period and ventricular functional refractory period. Furthermore, the degree of protection offered by the neonatal atriovenous node to the ventricle appears to be comparable to that of the adult.
Prolonged Exposure (PE) for Treatment of Childhood Sexual Abuse-Related PTSD: Do We Need to Augment It?

Kramer's thoughtful and extremely thorough case study of treating Caroline, a survivor of childhood sexual abuse (CSA), raises several important issues. A major assumption underlying Kramer's approach with Caroline's PTSD symptoms is that the Prolonged Exposure (PE) manualized treatment of Foa and her colleagues is a necessary but not sufficient method to address the clinical needs of such a client. Thus Kramer begins his treatment of this client with other clinical components, such as an assessment of Caroline's interpersonal patterns utilizing Caspar'sPlan Analysis method; custom tailoring of his therapeutic relationship with Caroline; imaginative relaxation; cognitive crisis intervention; and interventions to enhance the client's social competence. He then initiates a brief course of in vivo and imaginal exposure, following the procedures in the PE manual. In this commentary, we critically evaluate this major assumption of Kramer's and review data which argue that PE can be sufficient for treating clients like Caroline. Specifically, our commentary considers the following questions: (a) What are the effects of exposure alone versus exposure combined with other treatments for PTSD? (b) Does CSA-related PTSD require additional treatment components other than PE? (c) Is PE intolerable without additional interventions? (d) Why is length of treatment important? and (e) What are some of the issues raised by the manner in which Kramer implemented the PE treatment?
Instantaneous amplitude and frequency estimation: performance bounds and applications to source localization

Estimation and tracking of the instantaneous amplitudes and frequencies of superimposed, slowly varying narrowband signals is a difficult signal processing problem that shows up in many applications. Our approach to this problem is to achieve global noise averaging via SVD-based rank reduction of a matrix constructed from the entire data record. Compared to methods that use local noise averaging using many smaller matrices, the strength of the new approach is in affecting better noise reduction at a lower computational cost. Moreover, no model is needed for the variation of the amplitudes and frequencies with time. In this paper, Cramer-Rao bounds for the variance of the error in tracking the instantaneous amplitudes and frequencies (without assuming a parametric model for their variation with time) will be presented. In addition, we will also show how the algorithm can be used on sensor array data to estimate range and direction of multiple narrow-band sources.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Effects of MK-801 on rough-and-tumble play in juvenile rats

Effects of the noncompetitive N-methyl-D-aspartate (NMDA) channel blocker, MK-801, on play behavior and activity were assessed in juvenile rats. A low dose (0.025 mg/kg) of MK-801 significantly increased both pinning and dorsal contacts, two indices of play behavior in the rat. Higher doses (> or = 0.1 mg/kg) significantly reduced both measures of play, with play being virtually abolished at 0.2 mg/kg. Simultaneous measurements of activity indicated that the reductions of play at the higher doses were accompanied by significant increases in horizontal activity. There was also a dose-related reduction in rearing, which was significant at all doses. When juvenile rats were tested individually for activity in an open field, MK-801 increased horizontal activity at 0.2 mg/kg and decreased rearing at all doses. So while the effects of MK-801 on play are biphasic, the effects of this compound on locomotor activity, per se, are linear. These data suggest that the effects of NMDA channel blockade on overall activity and play are mediated through independent neural systems.
Tylerianthus crossmanensis gen. et sp. nov. (aff. Hydrangeaceae) from the Upper Cretaceous of New Jersey.

A fossil flower with affinities to the modern families of the saxifragalean complex is described. Fossils were collected at Old Crossman Pit, Raritan Formation, New Jersey, USA. These sediments are dated on the basis of palynology as Turonian (Upper Cretaceous, ;90 million years before present). Fossils are charcoalified and preserved with exceptional threedimensional detail. The characters observed in these flowers, when compared with those of extant flowers of several families of the saxifragalean complex, suggest a close relationship with extant members of the Saxifragaceae and Hydrangeaceae. Hypotheses on the origin of petals and staminodes and a possible mechanism of pollination are discussed. This new taxon provides additional characters in the floral morphology of the fossil saxifragoids and extends their geographical distribution in the Cretaceous to North America.
Scanning the capital horizon

The capital shortage is an issue that surfaced in 1974, during a period of shortages and bottlenecks for basic commodities and production materials in key industries; liquidity squeeze and balance sheet instability for households, corporations and banks; rapid inflation; and escalating interest rates. This combination of circumstances was unique to the postwar period, although other business cycle episodes since World War II have been characterized by some of the same elements.
The electric field equivalent of the Faraday effect: A computer simulation

Abstract First order electric field induced optical rotatory dispersion, the analogue of the Faraday effect, is investigated in liquid bromochlorofluoromethane with molecular dynamics computer simulation, using a time varying electric field to conserve reversality. Frequency dependent features are identified which are the spectral signatures of electric circular dichroism and birefringence. These results indicate clearly, and for the first time, that there exists, under the right conditions, an electric analogue of the Faraday effect, mediated by the molecular electric hyperpolarisability tensor.
GroEL interacts transiently with oxidatively inactivated rhodanese facilitating its reactivation.

Abstract When the enzyme rhodanese was inactivated with hydrogen peroxide (H2O2), it underwent significant conformational changes, leading to an increased exposure of hydrophobic surfaces. Thus, this protein seemed to be an ideal substrate for GroEL, since GroEL uses hydrophobic interactions to bind to its substrate polypeptides. Here, we report on the facilitated reactivation (86%) of H2O2-inactivated rhodanese by GroEL alone. Reactivation by GroEL required a reductant and the enzyme substrate, but not GroES or ATP. Further, we found that GroEL interacted weakly and/or transiently with H2O2-inactivated rhodanese. A strong interaction with rhodanese was obtained when the enzyme was pre-incubated with urea, indicating that exposure of hydrophobic surfaces alone on oxidized rhodanese was not sufficient for the formation of a strong complex and that a more unfolded structure of rhodanese was required to interact strongly with GroEL. Unlike prior studies that involved denaturation of rhodanese through chemical or thermal means, we have clearly shown that GroEL can function as a molecular chaperone in the reactivation of an oxidatively inactivated protein. Additionally, the mechanism for the GroEL-facilitated reactivation of rhodanese shown here appears to be different than that for the chaperonin-assisted folding of chemically unfolded polypeptides in which a nucleotide and sometimes GroES is required.
Microtubule assembly: pathways, dynamics, and regulators

The cellular regulation of microtubule assembly and organization is a central aspect of cell locomotion and intracellular motility. Approaches to understanding these regulatory mechanisms, including the applications of genetics, biochemistry and microscopy, have uncovered special and interesting features of microtubule assembly. Recent experiments provide new insight into the properties of the tubulin subunits in the assembly reaction and the nature of the polymer itself.
Sufficient convergence conditions for interation schemes modelled by point-to-set mappings

Abstract Sufficient conditions are compared for the convergence of abstract iteration schemes that consist of the recursive applications of nonstationary point-to-set mappings.
Does radiofrequency ablation preserve long-term renal function in patients with small renal masses?

Does radiofrequency ablation preserve long-term renal function in patients with small renal masses?
Degradation of chlorinated polyethylene—III: Effect of additives on dehydrochlorination and oxygen absorption

Degradation of chlorinated polymers takes place via two simultaneous reactions; namely, dehydrochlorination and oxygen absorption. The dehydrochlorination and oxygen absorption of five grades of chlorinated polyenthylenes were studied at temperatures varying between 120 and 180°C. The chlorinated polyethylene grades varied in both molecular weight and chlorine content, the latter being in the range of 24.0 to 45.2 percent chlorine. Dehydrochlorination measurements on the pure polymers in both nitrogen and oxygen atmospheres showed that the rate of dehydrochlorination increases with an increase in the degree of chlorination of the polymer. The oxygen absorption rate, however, showed a decrease with higher chlorine content of the polymer. Dehydrochlorination and oxygen absorption studies were also carried out on chlorinated polyethylene containing dehydrochlorination stabilizers, antioxidants, antimony oxide, and other metal salts and metal oxides. Retardation of both oxygen absorption and dehydrochlorination was observed in the presence of antioxidants. More significant, however, was the observed action of some dehydrochlorination stabilizers as efficient antioxidants in the polymer.
A Short Report on the RSA Chip

The nMOS “RSA chip” described in our article [1] was initially fabricated by Hewlett-Packard. Testing revealed that while the control portion of the chip worked correctly, the arithmetic section suffered from transient errors and was usually too unreliable to complete a full encryption. We tested a number of chips and found the same problem, enough to convonce us that the cause was probably a design error and not a fabrication problem.
A mathematical basis for the application of the modified geometric method to maximum frequency estimation

The application of ultrasound in assessing the fetal cardiovascular system often requires the accurate estimation of maximum blood flow velocity waveforms using Doppler measurements. The modified geometric method estimates the maximum Doppler frequency as the frequency at which the vertical distance between the integrated spectrum and the reference line that connects the origin to the maximum value of the integrated spectrum is the largest. This paper presents a mathematical formulation for a class of maximum blood flow velocity estimation algorithms that includes the modified geometric method. The analysis provides a rationale for the continued use of the modified geometric method for estimating the maximum frequency envelopes of Doppler signals. This paper also contains experimental results demonstrating the superiority of the modified geometric method over a commonly used threshold crossing method.
Crystallization kinetics of yttrium aluminum garnet (Y 3 Al 5 O 12 )

The kinetics and pathways for crystallization of solid, amorphous, yttrium aluminum garnet (YAG) were studied using isothermal differential thermal analysis, x-ray diffraction, and transmission electron microscopy. The activation energy for crystallization was 437 KJ/mol and the measured Avrami exponent was 2.74, which corresponded to three-dimensional crystal growth with a constant number of nuclei. Time–temperature–transformation (T–T–T) curves were developed from the data to predict crystallization rates as a function of temperature. The crystallization pathway for YAG in this system is compared to others reported in the literature.
The Middle Tier in American Federalism: State Government Policy Activism During the Bush Presidency

Demarcations and assessments of particular periods of American federalism typically focus attention on national–state relationships, and ignore the independent activities of the 50 states. Labels applied to a period are often based on the federalism stance taken by a president. One can think of Lyndon Johnson’s ‘‘creative federalism,’’ Richard Nixon’s ‘‘new federalism,’’ and Ronald Reagan’s ‘‘new, new federalism.’’ President George W. Bush, unlike some of his recent predecessors, has not proclaimed his own distinct vision of federal relationships, and consequently efforts to describe and assess the character of federalism during his administration must rely on a review of policy actions (or inactions). Because a sole focus on national–state relations ignores the ability of state governments, either singly or in combination, to adopt policies different from those of the federal government, it is also necessary to examine this independent policy activism as part of any assessment of an era in American federalism. This article begins with a discussion of state government response to the centralizing thrust of Bush policy proposals and his reversal of his party’s previous stance supportive of states’ rights. To capture more fully the condition of federalism during the Bush presidency, the analysis then moves to an examination of independent policy action by state governments, or what Elazar (1972, 174) termed ‘‘federalism without Washington.’’ The essay concludes with an effort to explain how and why the ‘‘middle tier’’ in American federalism has been so assertive during the George W. Bush presidency.
Role of atomic mobility in the transition noise of longitudinal media

The relationship between grain growth morphology and the transition noise of high-density CoPtCr media on Cr underlayers is examined. The growth morphology is shown to depend on the sputtering pressure, substrate bias, and substrate temperature. Development of isolated magnetic grains is promoted when the mobility of the sputtered atoms is reduced, i.e. at high sputtering pressure, low substrate temperature, and no substrate bias. As the magnetic grains become more isolated, the media transition noise is significantly reduced, accompanied by a simultaneous reduction in the coercive squareness. This indicates that the transition noise is primarily governed by the intergranular exchange coupling among the magnetic grains, which can be optimized by controlling the grain growth morphology. The microstructural features of the decoupled media correspond to the zone I structure in J.A. Thornton's (1986) microstructure zone diagram. >
Effect of Climate Change on Siberian Infrastructure

This chapter examines effects of climate change on human infrastructure in permafrost regions of Siberia. The presence and dynamic nature of ice-rich permafrost constitute a distinctive engineering environment. Many engineering problems in Siberia are associated with (1) changes in the temperature of the upper permafrost, (2) increased depth of seasonal thaw penetration, and (3) progressive thawing and disappearance of permafrost. These changes can lead to loss of soil bearing strength, increased soil permeability, and increased potential for development of such cryogenic processes as differential thaw settlement and heave, and development of thermokarst terrain. Each of these phenomena has the capacity for severe negative consequences on human infrastructure in the high latitudes. Results to date indicate that major permafrost-related impacts have already been detected in many Siberian regions, including changes in the temperature and distribution of permafrost, thickening of the seasonally thawed layer (the active layer), and changes in the distribution and quantity of ice in the ground. A quantitative geographic assessment of the ability of frozen ground to support engineering structures under rapidly changing climatic conditions in a variety of settings is provided in this chapter. Results show substantial decreases of permafrost bearing capacity over the last 40 years in some regions of Northern Siberia. Although a substantial proportion of reported deformations of structures and buildings on permafrost can be attributed to climatic warming, other technogenic factors have to be considered. The socioeconomic crisis resulted in reduced infrastructure monitoring and maintenance in many cities on permafrost during the early 1990s which have greatly contributed to the decrease in infrastructure stability.
Characterization of tri‐o‐methylcellulose by one‐ and two‐dimensional NMR methods

Tri-O-methylcellulose was prepared from partially O-methylated cellulose and its chemical shifts ( 1 H and 13 C), and proton coupling constants were assigned using the following NMR methods: (1) One-dimensional 1 H and 13 C spectra of the title compound were used to assign functional groups and to compare with literature data; (2) double quantum filtered proton-proton correlation spectroscopy ( 1 H, 1 H DQF-COSY) was used to assign the chemical shifts of the network of 7 protons in the anhydroglucose portion of the repeat unit; (3) the heteronuclear single-quantum coherence (HSQC) spectrum was used to establish connectivities between the bonded protons and carbons; (4) the heteronuclear multiple-bond correlation (HMBC) spectrum was used to connect the hydrogens of the methyl ethers to their respective sugar carbons; (5) the combination of HSQC and HMBC spectra was used to assign the 13 C shifts of the methyl ethers; (6) all spectra were used in combination to verify the assigned chemical shifts; (7) first-order proton coupling constants data (J H,H in Hz) were obtained from the resolution-enhanced proton spectra. The NMR spectra of tri-O-methylcellulose and other cellulose ethers do not resemble the spectra of similarly substituted cellobioses. Although the 1 H and 13 C shifts and coupling constants of 2,3,6-tri-O-methylcellulose closely resemble those of methyl tetra-O-methyl-β-D-glucoside, there are differences with regard to the chemical shifts and the order of appearances of the resonating nuclei of the methyl ether appendages and the proton at position 4 in the pyranose ring. H4 in tri-O-methylcellulose is deshielded by the acetal system comprising the β-1→4 linkage, and it resonates downfield. H4 in the permethylated glucoside is not as deshielded by the equitorial O-methyl group at C4, and it resonates upfield. The order of appearance of the 1 H and 13 C resonances in the spectra of the tri-O-methylcellulose repeat unit (from upfield to downfield) are H2 < H3 < H5 < H6a < H3a < H2a < pro R H6B < H4 < pro S H6A « H1 and C6a < C3a < C2a < C6 < C5 < C4 < C2 < C3 « C1, respectively. Close examination of the pyranose ring coupling constants of the repeat unit in tri-O-methylcellulose supports the 4 C 1 arrangement of the glucopyranose ring. Examination of the proton coupling constants about the C5-C6 bond (J 5,6A and J 5,6B ) in the nuclear Overhauser effect difference spectra revealed that the C6 O-methyl group is predominantly in the gauche gauche conformation about the C5-C6 bond for the polymer in solution.
Xen-Based HPC: A Parallel I/O Perspective

Virtualization using Xen-based virtual machine environment has yet to permeate the field of high performance computing (HPC). One major requirement for HPC is the availability of scalable and high performance I/O. Conventional wisdom suggests that virtualization of system services must lead to degraded performance. In this presentation, we take on a parallel I/O perspective to study the viability of Xen-based HPC for data-intensive programs. We have analyzed the overheads and migration costs for parallel I/O programs in a Xen-based virtual machine cluster. Our analysis covers PVFS-based parallel I/O over two different networking protocols: TCP-based Gigabit Ethernet and VMM-bypass InfiniBand. Our experimental results suggest that network processing in Xen-based virtualization can significantly impact the performance of Parallel I/O. By carefully tuning the networking layers, we have demonstrated the following for Xen-based HPC I/O: (I) TCP offloading can help achieve low overhead parallel I/O; (2) parallel reads and writes require different network tuning to achieve good I/O bandwidth; and (3) Xen-based HPC environment can support high performance parallel I/O with both negligible overhead and little migration cost.
Alterations in T-Cell Receptor Vβ Repertoire of CD4 and CD8 T Lymphocytes in Human Immunodeficiency Virus-Infected Children

Perturbations in the T-cell receptor (TCR) Vβ repertoire were assessed in the CD4 and CD8 T lymphocytes of human immunodeficiency virus (HIV)-infected children who were receiving therapy during the chronic phase of infection by flow cytometry (FC) and PCR analysis. By FC, representation of 21 TCR Vβ subfamilies was assessed for an increased or decreased percentage in CD4 and CD8 T cells, and by PCR, 22 TCR Vβ subfamilies of CD4 and CD8 T cells were analyzed by CDR3 spectratyping for perturbations and reduction in the number of peaks, loss of Gaussian distribution, or clonal dominance. The majority of the TCR Vβ subfamilies were examined by both methods and assessed for deviation from the norm by comparison with cord blood samples. The CD8-T-lymphocyte population exhibited more perturbations than the CD4 subset, and clonal dominance was present exclusively in CD8 T cells. Of the 55 total CD8-TCR Vβ families classified with clonal dominance by CDR3 spectratyping, only 18 of these exhibited increased expression by FC. Patients with high numbers of CD8-TCR Vβ families with decreased percentages had reduced percentages of total CD4 T cells. Increases in the number of CD4-TCR Vβ families with increased percentages showed a positive correlation with skewing. Overall, changes from normal were often discordant between the two methods. This study suggests that the assessment of HIV-induced alterations in TCR Vβ families at cellular and molecular levels yields different information and that our understanding of the immune response to HIV is still evolving.
Health Effects of Organic Aerosols

Carbonaceous aerosol, a major component of particulate matter (PM), gases, and vapors in the atmosphere, has been associated with natural and anthropogenic air pollution, reduced visibility, climate modulation, material and ecosystem damage, and adverse health effects. More recently, epidemiological studies have indicated associations between organic fractions of ambient PM and adverse respiratory and cardiovascular health outcomes. The effects of the non-PM components of the organic aerosol have received less attention because their measurement in the general environment is not mandated. This article summarizes current knowledge of the nature, prevalence, and health effects of organic aerosols encountered in the outdoor environment, identifies key information gaps, and presents a conceptual framework for research priorities for resolving those gaps. The broad, diverse class of air contaminants comprising organic aerosols may be more important to public health than the modest attention given to them. This review focuses on hazard identification and exposure assessment for evaluating risks to public health from ambient organic aerosols. Current knowledge is insufficient to support a quantitative characterization of the aggregate risk from organic air contaminants. Assessments should be done for individual species or mixtures. Efforts should be taken to assemble and evaluate a common set of standard reference materials for both organic speciation and health response assays. A greater standardization of approaches across studies and laboratories would be useful to achieve uniformity in assessing health effects. Multidisciplinary research efforts are needed to improve the current regulatory-driven air quality monitoring networks for epidemiological studies. The limited array of biomarkers linking organic aerosols to health effects needs to be expanded and specific organic compounds or classes that are associated with biological effects in human cells or animal studies need to be tested for better understanding of the exposure-response relationship.
Quantifying the Order of Spontaneous Ripple Patterns on Ion-Irradiated Si(111)

Uniform keV ion irradiation causes a morphological instability known to result in the spontaneous formation of topographic ripple and dot patterns. The degree of order of these patterns, which has important implications for non-lithographic patterning applications, varies markedly with fabrication conditions. We investigate the influence of systematic variations of fabrication conditions, including current density, ion fluence and ion energy, on the degree of order of argon ion bombarded Si(111) surfaces. For quantifying order in sputter rippled topographic images, we develop an algorithm that evaluates the density of topological defects, such as ripple bifurcations and terminations, and suitably normalizes the result in order to present a scalar figure of merit: the normalized defect density. We discuss fabrication conditions that lead to extremely well ordered dot and ripple patterns upon irradiation.
The Acute Effect of Environmental Tobacco Smoke Exposure on Asthmatics: Studies with a Dynamic Challenge Chamber

To determine the acute effects of environmental tobacco smoke on respiratory tract lung function, 130 asthmatics and 28 non-asthmatics were exposed up to 4 hours to side stream environmental tobacco smoke (SS-ETS) in a dynamic challenge chamber. The vast majority of the subjects exposed to SS-ETS reported upper respiratory and ocular irritant symptoms; the prevalence of these symptoms was not significantly associated with any particular study groups analyzed, or with the self-perception of tobacco smoke allergy by the study subject. All 28 SS-ETS-exposed non-asthmatics had no significant change in lung function, while 26/130 asthmatics demonstrated a significant drop in pulmonary function (FEV1≥20% decline), generally within 90 to 240 minutes after start of exposure. Classical late phase bronchoconstriction was not observed up to 24 hours following the challenge. Six/26 reactors had a significant drop in lung function following a sham control challenge, indicating that 20/130 asthmatics had a specific bronchoconstrictive response to SS-ETS. Responses to diminishing levels of SS-ETS demonstrated that some asthmatics can react to levels as low as 0.0128 cigarette – min/m3 (comparable to ETS levels in the homes of many smokers).
d -computable categoricity for algebraic fields

We use the Low Basis Theorem of Jockusch and Soare to show that all computable algebraic fields are d-computably categorical for a particular Turing degree d with d′ = 0″, but that not all such fields are 0′-computably categorical. We also prove related results about algebraic fields with splitting algorithms, and fields of finite transcendence degree over ℚ.
Beyond SES: A Resource Model of Political Participation

This paper develops a resource model of political participation. The resources considered are time, money, and civic skills—those communications and organizational capacities that are essential to political activity. These skills are not only acquired early in life but developed in the nonpolitical institutional settings of adult life: the workplace, organizations, and churches and synagogues. These resources are distributed differentially among groups defined by socioeconomic status. A two-stage least squares analysis shows these resources have powerful effects on overall political activity, thus explaining why socioeconomic status has traditionally been so powerful in predicting participation. We disaggregate overall activity into three kinds of acts: those that involve giving time, those that entail donating money, and voting. Each requires a different configuration of resources resulting in different patterns of stratification across various political acts.
Increased Probability of GABA Release during Withdrawal from Morphine

Opioid receptors located on interneurons in the ventral tegmental area (VTA) inhibit GABA(A)-mediated synaptic transmission to dopamine projection neurons. The resulting disinhibition of dopamine cells in the VTA is thought to play a pivotal role in drug abuse; however, little is known about how this GABAA synapse is affected after chronic morphine treatment. The regulation of GABA release during acute withdrawal from morphine was studied in slices from animals treated for 6-7 d with morphine. Slices containing the VTA were prepared and maintained in morphine-free solutions, and GABAA IPSCs were recorded from dopamine cells. The amplitude of evoked IPSCs and the frequency of spontaneous miniature IPSCs measured in slices from morphine-treated guinea pigs were greater than placebo-treated controls. In addition, activation of adenylyl cyclase, with forskolin, and cAMP-dependent protein kinase, with Sp-cAMPS, caused a larger increase in IPSCs in slices from morphine-treated animals. Conversely, the kinase inhibitors staurosporine and Rp-CPT-cAMPS decreased GABA IPSCs to a greater extent after drug treatment. The results indicate that the probability of GABA release was increased during withdrawal from chronic morphine treatment and that this effect resulted from an upregulation of the cAMP-dependent cascade. Increased transmitter release from opioid-sensitive synapses during acute withdrawal may be one adaptive mechanism that results from prolonged morphine treatment.
MaPle: a fast algorithm for maximal pattern-based clustering

Pattern-based clustering is important in many applications, such as DNA micro-array data analysis, automatic recommendation systems and target marketing systems. However, pattern-based clustering in large databases is challenging. On the one hand, there can be a huge number of clusters and many of them can be redundant and thus make the pattern-based clustering ineffective. On the other hand, the previous proposed methods may not be efficient or scalable in mining large databases. We study the problem of maximal pattern-based clustering. Redundant clusters are avoided completely by mining only the maximal pattern-based clusters. MaPle, an efficient and scalable mining algorithm is developed. It conducts a depth-first, divide-and-conquer search and prunes unnecessary branches smartly. Our extensive performance study on both synthetic data sets and real data sets shows that maximal pattern-based clustering is effective. It reduces the number of clusters substantially. Moreover, MaPle is more efficient and scalable than the previously proposed pattern-based clustering methods in mining large databases.
Parasympathetic Influences on Cerebral Circulation: A Link to Arterial Baroreflexes

It has long been known that arterial baroreflexes participate in regulating peripheral vascular tone, but there has been little evidence to link those reflexes to regulation of the cerebral circulation. In studies reviewed here we show that arterial baroreceptor reflexes modulate cerebrovascular tone through a pathway that connects the cardiovascular nucleus tractus solitarii with parasympathetic preganglionic neurons in the pons. Utilizing laser flowmetry in anesthetized rats we assessed autoregulation of cerebral blood flow while blood pressure was slowly increased in response to i.v. infusion of phenylephrine. Intact control animals demonstrated classic autoregulation and breakthrough, an increase of cerebral blood flow, when pressure exceeded the upper limit of autoregulation. However, breakthrough was attenuated or abolished in animals with lesions of baroreceptor nerves, the nucleus tractus solitarii where those nerves would terminate, the pontine preganglionic parasympathetic neurons, or the parasympathetic ganglionic nerves to the cerebral vessels. Similarly blocking synthesis of nitric oxide, which is released by the parasympathetic nerves from the pterygopalatine ganglia, also attenuated breakthrough of autoregulation during hypertension. While interruption of function of the pontine preganglionic neurons reduced cerebrovascular dilatation during hypertension, stimulation of those neurons caused cerebral vasodilatation. We performed anatomical studies to complement these physiological experiments and defined a pathway that could mediate baroreflex influences on cerebral blood vessels. Retrograde and anterograde tracing studies showed that neurons in the cardiovascular region of the nucleus tractus solitarii projected to and synapsed with preganglionic neurons of the superior salivatory nucleus. The synapses formed were of an asymmetric type and were thus consistent with excitatory synapses. These studies provide strong evidence that arterial baroreceptors may modulate cerebral blood flow through direct connections with pontine parasympathetic neurons. We conjecture that the pathway may participate in integrating the various functions mediated by those pontine parasympathetic preganglionic neurons.