cssi/SciSciGPT-SciSciNet huggingface dataset:
Model Checking the World Wide Web

Web design is an inherently error-prone process. To help with the detection of errors in the structure and connectivity of Web pages, we propose to apply model-checking techniques to the analysis of the World Wide Web. Model checking the Web is different in many respects from ordinary model checking of system models, since the Kripke structure of theWeb is not known in advance, but can only be explored in a gradual fashion. In particular, the model-checking algorithms cannot be phrased in ordinary µ-calculus, since some operations, such as the computation of sets of predecessor Web pages and the computations of greatest fixpoints, are not possible on the Web. We introduce constructive µ-calculus, a fixpoint calculus similar to µ-calculus, but whose formulas can be effectively evaluated over the Web; and we show that its expressive power is very close to that of ordinary µ-calculus. Constructive µ-calculus can be used not only for phrasing Web model-checking algorithms, but also for the analysis of systems having a large, irregular state space that can be only gradually explored, such as software systems. On the basis of these ideas, we have implemented the Web model checker MCWEB, and we describe some of the issues that arose in its implementation, as well as the type of errors that it was able to find.
VLA High-Sensitivity 4He Imaging of Galactic H II Regions

We have carried out 8.3 GHz hydrogen and helium radio recombination line and continuum observations of three Galactic H II regions with the NRAO 140 Foot Telescope and the Very Large Array. These observations measure the spatial variations in the singly ionized helium-to-hydrogen abundance ratio, 4He+/H+ (y+), and probe for any localized enhancements in y+. The three observed regions (W43, NGC 6334A, and K3-50) are morphologically complex, and high-resolution, wide field observations are crucial to measure the helium abundances on scales that would be associated with individual massive stars or clusters of stars. The nearly constant y+ value across the W43 source (W43 = 7.7% ± 1%) indicates that any ionization correction over the spatial scales investigated is small. Such ionization corrections are important for calculating total abundances of the light element 3He, which is measured in the Galaxy via a singly ionized hyperfine transition. Localized enhancements in the y+ value have been detected in both NGC 6334A (y+ = 20% ± 4%) and K3-50A (y+ = 24% ± 5%). The 4He abundance results are discussed along with other measurements of the physical properties of these H II regions, such as the kinematics and excitation.
Transcriptomics as a Tool for Assessing the Scalability of Mammalian Cell Perfusion Systems

DNA microarray-based transcriptomics have been used to determine the time course of laboratory and manufacturing-scale perfusion bioreactors in an attempt to characterize cell physiological state at these two bioreactor scales. Given the limited availability of genomic data for baby hamster kidney (BHK) cells, a Chinese hamster ovary (CHO)-based microarray was used following a feasibility assessment of cross-species hybridization. A heat shock experiment was performed using both BHK and CHO cells and resulting DNA microarray data were analyzed using a filtering criteria of perfect match (PM)/single base mismatch (MM) > 1.5 and PM-MM > 50 to exclude probes with low specificity or sensitivity for cross-species hybridizations. For BHK cells, 8910 probe sets (39 %) passed the cutoff criteria, whereas 12,961 probe sets (56 %) passed the cutoff criteria for CHO cells. Yet, the data from BHK cells allowed distinct clustering of heat shock and control samples as well as identification of biologically relevant genes as being differentially expressed, indicating the utility of cross-species hybridization. Subsequently, DNA microarray analysis was performed on time course samples from laboratory- and manufacturing-scale perfusion bioreactors that were operated under the same conditions. A majority of the variability (37 %) was associated with the first principal component (PC-1). Although PC-1 changed monotonically with culture duration, the trends were very similar in both the laboratory and manufacturing-scale bioreactors. Therefore, despite time-related changes to the cell physiological state, transcriptomic fingerprints were similar across the two bioreactor scales at any given instance in culture. Multiple genes were identified with time-course expression profiles that were very highly correlated (> 0.9) with bioprocess variables of interest. Although the current incomplete annotation limits the biological interpretation of these observations, their full potential may be realized in due course when richer genomic data become available. By taking a pragmatic approach of transcriptome fingerprinting, we have demonstrated the utility of systems biology to support the comparability of laboratory and manufacturing-scale perfusion systems. Scale-down model qualification is the first step in process characterization and hence is an integral component of robust regulatory filings. Augmenting the current paradigm, which relies primarily on cell culture and product quality information, with gene expression data can help make a substantially stronger case for similarity. With continued advances in systems biology approaches, we expect them to be seamlessly integrated into bioprocess development, which can translate into more robust and high yielding processes that can ultimately reduce cost of care for patients.
A Robust Adaptive Controller for Continuous Time Systems

We prove the stability of an adaptively-controlled continuous-time plant of relative degree one in the presence of unmodeled dynamics. Specifically, we show that if the unmodeled dynamics are small in some sense, then all the signals in the closed-loop system remain bounded. Further, we show that robust performance is achieved in the sense that the mean-square tracking error converges to zero linearly with the unmodeled dynamics. In the absence of unmodeled dynamics, we show that the tracking error asymptotically goes to zero. The adaptation law considered is the usual gradient update law with projection. This shows that modifications such as normalization or relative dead-zones are not necessary to achieve stability in the presence of unmodeled dynamics.
Correlation of the ballistocardiogram with the coronary angiogram and electrocardiogram in ischemic heart disease

Abstract Ballistocardiograms were obtained in 63 patients who were studied by coronary angiography to establish the presence or absence of coronary artery disease. Correlation of the ballistocardiogram was also made with electrocardiograms at rest and after exercise. Of 32 patients with angina pectoris, all but 7 had abnormal coronary angiograms. These seven had evidence of aortic valvular disease as the cause of chest pain. The ballistocardiogram was abnormal in 18. In 31 patients without angina pectoris, only 2 of whom had abnormal coronary angiograms, there were 8 abnormal ballistocardiograms. There was no predictable correlation of the ballistocardiogram with the electrocardiogram at rest or after exercise. It is concluded that the resting ballistocardiogram is unreliable for routine diagnostic use, although it may in some cases provide helpful ancillary information.
A Model of Religious Choice Under Uncertainty On Responding Rationally to the Nonrational

This article analyzes a general model of religious choice under uncertainty by interpreting Pascal's wager as an expected utility problem and faith as insurance. The authors assert that the basic r...
Synthesis and properties of thermally reversible polyesters

Thermally reversible polyesters were obtained by the ester formation reaction of thermoplastic polyesters with hydroxyl end groups and the diacid anhydride of tetra carboxylic acid as a thermally reversible chain extender. Typical example of the thermally reversible polyesters was obtained by the reaction of PBT (polybutylene terephthalate) and PMA (pyromellitic dianhydride). This material having twice as large molecular weight as the original PBT exhibited almost the same melt viscosity as the original. Also that thermally reversible chain extension reaction occurred without unfavorable side reaction such as cross-linking. This material shows both good processability and superior mechanical properties due to its thermally reversible characters.
Inactivation of Escherichia coli O157:H7 during storage or drying of apple slices pretreated with acidic solutions.

Abstract Inactivation of Escherichia coli O157:H7 was evaluated on inoculated apple slices without pretreatment or pretreated by immersing in water or acid solutions commonly used to help retain apple color during dehydration, then stored at ambient temperature or dried for 6 h. Half-ring slices (0.6 cm thick) of peeled and cored Gala apples were inoculated by immersion for 30 min in a three-strain composite inoculum of E. coli O157:H7 (7.8–8.0 CFU/g). Inoculated slices received (1) no pre-drying treatment (control); or a 10-min immersion in solutions of (2) sterile water, (3) 2.8% ascorbic acid, (4) 1.7% citric acid, (5) 50% commercial lemon juice, or (6) 50% commercial lemon juice with preservatives. Drained slices were placed in sterile plastic bags and stored at room temperature (25±2 °C) for up to 6 h or dehydrated (62.8 °C) for up to 6 h. Samples were plated on tryptic soy agar (TSA) and sorbitol MacConkey agar (SMAC) for direct enumeration of surviving bacteria at various time intervals. Immersion in sterile water or acidic solutions caused initial bacterial reductions of 0.9–1.3 log CFU/g on apple slices. Between 0 and 6 h of storage at room temperature, slices dipped in acidic solutions showed minor changes in bacterial populations (−0.2 to +0.6 log CFU/g) compared to a 1.1 log CFU/g increase for slices dipped in sterile water. The no treatment samples (control) showed an increase in bacterial populations of 1.3–1.5 CFU/g over the 6-h holding time. For apple slices dried at 62.8 °C, bacterial populations were reduced by 2.5 (SMAC) and 3.1 (TSA) log CFU/g in the control (no pre-drying treatment) samples following 6 h dehydration. The slices immersed in sterile water showed a 5.8 (SMAC) and 5.1 (TSA) reduction after 6 h of dehydration. In contrast, after 6 h of dehydration bacterial populations on the four acid-pretreated products were reduced by 6.7–7.3 log CFU/g. The results showed that acidic treatment alone was not effective in destroying E. coli O157:H7 on apple slices but did inhibit growth of the organism during holding before drying. However, pretreatment of the apple slices with common household acidulants enhanced destruction of E. coli O157:H7 during drying compared to slices dried without treatment.
Alternative Approaches for the Surgical Treatment of Significant Mitral Regurgitation in Advanced Heart Failure

Purpose Moderate-severe mitral regurgitation (MR) accompanying advanced systolic dysfunction is associated with increased risk of morbidity/mortality. Mitral valve repair/replacement (MVR) in this population remains controversial. Continuous flow LVAD (cfLVAD) may be an alternative therapy, but patient selection and outcomes data is lacking. Methods and Materials Patients with advanced heart failure receiving cfLVAD (n=95) or MVR (n=85) between 1/05 and 6/12 at our center were retrospectively reviewed. Baseline characteristics and post-operative outcomes were compared. Results MVR pts more commonly had hypertension and coronary artery disease (p Conclusions In this population cfLVAD is associated with increased 30-day morbidity but similar intermediate survival relative to MVR. Our results suggest that as these pts move along a risk continuum of worsening heart failure, cfLVAD implantation provides a survival advantage similar to high risk MVR in a less sick population. Thus, cfLVAD might be an important alternative therapy, especially as devices advance and VAD management and outcomes improve. Patient Outcomes MVR cfLVAD p-Value LOS (Days; Median[Q1,Q3]) 9.0 [7.0,12.0] 17.0 [12.0,25.0] 30-Day Mortality 6/85 (7.1%) 7/95 (7.8%) 1.0 1-Year Mortality 1485 (16.5%) 15/95 (15.8%) 1.0 Reoperation 11/85 (12.9%) 40/95 (42.1%) MI 5/85 (5.9%) 0/95 0.022 Hemorrhage 6/85 (7.1%) 31/95 (32.6%) Respiratory Failure 7/85 (8.2%) 30/95 (31.6%) 30-Day Readmit 11/85 (12.9%) 23/95 (24.2%) 0.059
Log likelihood ratios for convolutionally encoded parity bit selected DS-SS system

In this paper we investigate the performance of the parity bit selected direct sequence spread spectrum (DS-SS) system using log likelihood ratio (LLR). In this system information bits are convolutionally encoded prior to being used in the parity bit selected DS-SS system. Reliability of the detected bits in the receiver is calculated in the form of LLRs and then used as the input of a soft input Viterbi decoder. The performance of the proposed system is compared to conventional coded spread spectrum systems where no parity bit selected spreading sequence is used.
Mechanism for Further Enhancement in Drug Dissolution from Solid-Dispersion Granules upon Storage

The present study was performed to investigate the further increase in drug dissolution on storage of ternary solid-dispersion granules containing poorly water-soluble drugs. Ternary solid-dispersion granules of the drug, a dispersion carrier, and a surface adsorbent were prepared using hot-melt granulation. Two proton-donating drugs, BAY 12-9566, naproxen, and a nonproton-donating drug, progesterone, were studied. Gelucire 50/13 and polyethylene glycol 8000 were evaluated as solid-dispersion carriers with low melting point. Neusilin US2 (magnesium aluminosilicate), a proton acceptor, was used as the surface adsorbent. The proposed mechanism for further increase in drug dissolution (BAY 12-9566 and naproxen) on storage at 40 degrees C/75% RH (relative humidity) is based on hydrogen bonding between the proton-donating drugs and the surface adsorbent, Neusilin US2 (proton acceptor). We propose that there is enough mobility in the solid-dispersion granules at elevated temperatures of storage to allow an increase in the ratio of the hydrogen bonded drug to the crystalline drug. These changes are mediated through the saturated solid solution state, and manifest themselves as increased drug dissolution upon storage. Fourier transform infrared spectroscopy studies are indicative of an increase in the amount of drugs (BAY 12-9566 and naproxen) hydrogen bonded to Neusilin on storage. A corresponding decrease in the crystallinity of these drugs was measured using x-ray powder diffractometry. Granules containing progesterone (a nonproton-donating drug) do not show an increase in the amount of drug hydrogen-bonded to Neusilin upon storage. In contrast to the proton-donating drugs, decreased drug dissolution was found on storage of progesterone-containing granules.
Matrotrophic adaptations and early stages of embryogenesis in the desert scorpion Paruroctonus mesaensis (Vaejovidae)

Light and electron microscopy were used to examine the sequential changes in embryos and maternal reproductive tubules in the vaejovid scorpion, Paruroctonus mesaensis. The early stages are described, from oogenesis to the time of embryogenesis just before spiracles and booklungs begin to appear. The oocytes and associated trophic cells originate in the epithelium of the maternal ovariuterine tubules. Each oocyte with follicle (primary trophic) cells forms a protuberance on the tubular surface. After fertilization and cleavage, the morula appears to be pulled into the tubular lumen by tissue invaginated from the wall opposite the protuberance. Secondary trophic cells originating near each oocyte form a trophic layer parallel and connected to the ovariuterine tubules. These cells encircle the tubular epithelium and apparently induce or transform it to a trophic mode. Within the tubules, each embryo develops in a specialized region (uterus) where the embryo abuts a cell mass (follicular placenta). The latter, along with the tubular and uterine epithelia, apparently releases nutrients that are absorbed through the embryo epidermis. The main structures of the embryo body develop from the germinal disc of the blastula. Segments and appendages are formed in an anterior-to-posterior direction. The chelicerae, initially posterior to the stomodeum, are gradually positioned anterior and dorsal. The early abdomen has only a few segments with no separation into meso- and metasoma. The latter structure, when formed, has a ventral flexure and segments of smaller diameter than those in the mesosoma. The telson starts as a broad, bilobed structure, becoming tapered with two openings near the tip. Each pectine appears first as a lobe attached to the body wall. Transverse grooves appear distally and then later along the entire length. In the stages of this study, there was no indication of ventral plates, gills, or sternites in the ventral mesosoma where booklungs and spiracles will eventually form. J. Morphol. 237:187-211, 1998. © 1998 Wiley-Liss, Inc.
1311 PHENOTYPIC HETEROGENEITY IN THE JEUNE SYNDROME

Jeune syndrome (JS) is a rare autosomal recessive dysplasia which may present with asphyxiating thoracic dystrophy in the neonatal period or progressive renal or visual impairment in childhood and adolescence. Pathologic studies have shown cystic renal dysplasia and perlportal hepatic fibrosis in JS patients of all ages, but the incidence and clinical significance of these abnormalities is unknown because few surviving patients have been extensively evaluated. We report 7 patients with diagnostic radiologic findings of JS, 6 of whom were extensively evaluated. Patients 1, 2 & 3 presented as neonates, patients 4 & 5 in infancy and childhood and patients 6 & 7 as adolescents. Reasons for referral included: short stature (2), respiratory distress (2), renal disease (1), liver dysfunction (1) and incidental finding (1). Pts 4 & 7 were cl tnically well. Pts 1 & 2 had chronic pulmonary disease without clinical renal disease. Pt 6 had both chronic pulmonary disease and proteinuria. Pt 5 died of chronic renal failure. Both Pt 5 & 6 also had pigmentary retinopathy. Hepatic dysfunction occurred only in Pt 3; liver biopsy revealed fibrosis. These patients illustrate the multisystemic nature of JS and its variability in presentation. Although JS is classified as a skeletal dysplasia, its pleiotropic manifestations indicate a need for comprehensive evaluation in all patients with the disorder.
A Robust Nonlinear Filtering Approach to Inverse Halftoning

A new blind inverse halftoning algorithm based on a nonlinear filtering technique of low computational complexity and low memory requirement is proposed in this research. It is called blind since we do not require the knowledge of the halftone kernel. The proposed scheme performs nonlinear filtering in conjunction with edge enhancement to improve the quality of an inverse halftoned image. Distinct features of the proposed approach include efficiently smoothing halftone patterns in large homogeneous areas, additional edge enhancement capability to recover the edge quality, and an excellent PSNR performance with only local integer operations and a small memory buffer.
Polarity reversal in the Solomon Islands arc

McKenzie1 proposed that the direction of subduction beneath an island arc will reverse following arc–continent collision. Dewey and Bird2 suggested that such an arc polarity reversal occurred in northern New Guinea; Johnson and Molnar3, however, proposed two alternative models of plate convergence that could explain the observed seismicity. We present here a spatial seismicity study of the Solomon Islands region which has revealed the existence of two juxtaposed Wadati–Benioff (W–B) zones of opposite polarity. Shallow and intermediate foci define a north-east-dipping W–B zone associated with active subduction along the New Britain and San Cristobal trenches and a south-west-dipping W–B zone associated with the inactive North Solomon trench (NST). These data provide the first direct seismic evidence of a reversal in subduction polarity at an island arc.
Reactions of alkylcobalamins and of related complexes with mercaptide ions: S-alkylation by nucleophilic attack

Abstract The reaction of n-alkylcobalamins and of n-alkylcobalt derivatives of five different vitamin B12 model compounds with a variety of mercaptide ions yields thioethers. Reaction rates and yields of product are dependent on the size of the alkyl group, the in-plane ligand moiety, and the axial bases of the cobalt complexes. The reaction of methylcobalamin with CH2S− affords (CH2)2S in near quantitative yield and was shown to follow a second order rate law. This S-methylation reaction provides a model for the terminal step in the biosynthesis of methionine from methylcobalamin and homocysteine by a cobalamin-dependent enzyme of Escherichia coli. The reaction of alkylcobalt derivatives of cobaloximes and of several other model compounds with mercaptide ions also yields thioethers, but the yields are lower due to the occurrence of side-reactions (e.g., axial ligation by R-S−). The relative rates of the S-alkylation reactions nevertheless follow a pattern typical for SN2 displacement-rather than free radical reactions.
School censorship experiences of teachers in southern Appalachia

The impact of censorship experiences on 13 public school teachers in southern Appalachian communities was studied. Qualitative interviews with the teachers focused on the nature and meaning of censorship experiences and their impact on educational philosophy and curriculum practices. The 13 teacher‐participants experienced a total of 55 censorship events which spanned an array of topics, teaching methods, and materials. Only a few of the incidents became public. Most were unreported events that took place between a teacher and parent or other objector, suggesting that censorship may be more pervasive than is estimated by quantitative approaches. Conflicts between traditional values and the pressures of modernity within a culturally homogeneous region are examined.
Flicker detection in the albino rat following light-induced retinal damage

Abstract The effect of light-induced retinal damage on the behaving rat's critical flicker-fusion frequency (CFF) was studied by determining the CFF at scotopic and photopic luminances both before and after exposure to damaging light. The CFF was reduced but not abolished following damaging light exposure. The shapes of the functions relating CFF to luminance before and after exposure suggested that scotopic visual function may have survived the light damage better than did photopic function. Anatomical and biochemical measures of retinal damage indicated that 91–93% of the outer nuclear layer (ONL) and 99% of the rodopsin had been lost.
On lower bounds on the size of sums-of-squares formulas

Abstract For sums-of-squares formulas of the form ( x 1 2 + ⋯ + x r 2 ) ( y 1 2 + ⋯ + y s 2 ) = z 1 2 + ⋯ + z t 2 where the z i are bilinear functions of the x i and y i . Let L ( r , s ) denote the smallest possible value of t allowing such a formula to hold. We have two well-known lower bounds on the size of L ( r , s ) . One was obtained independently by Hopf and Stiefel, and another by Atiyah. These bounds are given by requiring certain binomial coefficients be divisible by certain powers of 2. Although the behavior of the Hopf–Stiefel bound is fairly well understood, the Atiyah bound is not. In this paper we provide an efficient algorithm for computing the Atiyah bound and some results on which of the lower bounds is larger.
Electrical conductivity of lumbar anulus fibrosis: effects of porosity and fixed charge density.

STUDY DESIGN Experimental investigation of the electrical conductivity of normal and trypsin-treated lumbar anulus fibrosis specimens. OBJECTIVES To measure the electrical conductivity of intervertebral disc tissues and to study the effects of tissue porosity (volume fraction of water) and fixed charge density on the electrical conductivity of anulus fibrosis in physiologic saline. SUMMARY OF BACKGROUND DATA Specific electrical conductivity is one of the material properties of intervertebral discs. Their value depends on ion concentrations and ion diffusivities within the tissue, which in turn are functions of tissue composition and structure. To our knowledge, the electrical conductivity of intervertebral discs has not been studied. Investigation of the electrical conductivity of intervertebral discs and understanding of their relationship to tissue porosity and fixed charge density will provide insights into electromechanical phenomena (e.g., streaming potential) and ion transport in intervertebral discs. METHODS A total of 35 porcine lumbar anulus fibrosis specimens were divided into two groups: one control group (n = 10) and one trypsin-treated group (n = 25). The specimens in the control group were subjected to one-dimensional free swelling in phosphate-buffered saline (pH 7.4), and electrical conductivity and porosity (water content) were measured over a period of about 45 minutes. The specimens in the treated group were immersed in a trypsin solution (372 U/mL phosphate-buffered saline) for 45 minutes at room temperature, and the electrical conductivity and porosity were measured after treatment. The electrical conductivity was correlated to tissue porosity for the control and treated specimens. The influences of porosity and fixed charge density were studied. RESULTS The average value for control specimens was 5.60 +/- 0.89 mS/cm (mean +/- SD; n = 10) before swelling and 9.11 +/- 0.90 mS/cm (mean +/- SD; n = 10) after swelling. Tissue porosity increased from 0.74 +/- 0.03 (mean +/- SD; n = 10) before swelling to 0.83 +/- 0.02 (mean +/- SD; n = 10) after swelling. The trypsin treatment reduced anulus fibrosis porosity by 3.6% (P < 0.05) and conductivity by 13% (P < 0.05) compared to those for control specimens after swelling. No significant changes werefound in wet and dry tissue densities between control and treated groups. There was a significant, linear correlation between conductivity and porosity for control anulus fibrosis specimens (R2 = 0.87; 86 measurements). CONCLUSIONS Measured electrical conductivity was sensitive to tissue porosity, but not to fixed charged density for anulus fibrosis specimens in phosphate-buffered saline.
Interaction of wheat germ agglutinin with human peripheral blood mononuclear cells. Binding kinetics and flow microfluorometric analysis

Abstract We have used binding experiments with radiolabeled lectin and flow microfluorometry to characterize the interaction of wheat germ agglutinin (WGA) with human peripheral blood mononuclear cell preparations. Results indicated that WGA bound to these cells in a complex fashion described by a curvilinear (upwardly concave) Scatchard plot and a nonlinear dissociation curve. Binding was rapid and reversible and was inhibited 80–90% by 0.1 M N -acetylglucosamine, a specific haptenic inhibitor of WGA binding. Approximately 1 5 of the total binding was attributable to monocytes, (but phagocytic uptake was excluded), and the remainder was due to lymphoid cell variants. Kinetics of binding were only modestly altered by formalin fixation of the cells mitigating against a role for site-site interactions in the generation of the non-linear Scatchard plot. Flow microfluorometric analysis revealed that the capability to bind WGA was a characteristic of only 35% of blood mononuclear cells and further allowed identification of a small cell subclass constituting less than 10% of the total that nonetheless accounted for fully one half of the entire WGA binding potential of these cells.
Effects of oxygen and constant positive pressure breathing on aADCO2 in hyaline membrane disease.

Summary: The effects of 100% oxygen breathing and constant positive pressure breathing (CPPB) on venous admixture (Qva/Qt) and arterial-alveolar difference for PCO2 (aADCO2) were examined in seven infants with hyaline membrane disease (HMD). Increasing FIO2 from 0.63-0.99 with CPPB constant at 2 cm H2O resulted in significant decrease in Qva/Qt from 0.67-0.47, but produced no change in aADCO2 (13.0 torr vs. 15.0 torr). Increasing CPPB to 8 cm H2O with FIO2 returned to 0.63 also resulted in decreased Qva/Qt (0.50), but in addition aADCO2 decreased significantly to 7.0 torr. The reduction in Qva/Qt with oxygen breathing and with CPPB is interpreted as a reduction in true right-to-left-shunt and a corresponding increase of effective blood flow through the lung. In 100% oxygen the increase in effective pulmonary perfusion occurred in a poorly ventilated compartment and as such was not reflected in the aADCO2. On the other hand, with CPPB, the increase in perfusion was accompanied by an increase in ventilation and, hence, the aADCO2 decreased. To illustrate these effects we constructed a three compartment model for the lung in HMD, calculated the VA/Qc for the well-ventilated compartment in each circumstance, constructed O2-CO2 diagrams and arrived at predicted values for the aADCO2 for each of the three clinical conditions. These predicted values agree well with those measured, considering the possible errors in our methods and assumptions and considering the absolute changes that may occur with CPPB, namely, increased cardiac output and decreased ventilation. This, in turn, provides strong support for the proposed three compartment model and for the existence of an open, but severely underventilated compartment in HMD. Speculation: In HMD, the aADCO2 seems to be responsive to the effects of CPPB on both ventilation and perfusion, and as such would be valuable clinically in determining optimal levels of CPPB.
Development of columnar-spheroidal structures by meteoric water in a New Mexico basalt

An unusual structure in a basalt flow near Wagon Mound, New Mexico, consists of large, polyhedral blocks, each having a fresh rim or shell and a spheroidally weathered interior. These blocks have features attributable to both columnar jointing and spheroidal weathering and are termed columnar-spheroidal structures. It is concluded that meteoric water has interacted with the basalt to produce the rims, as evidenced by (1) small clastic dikes emanating from water-laid ash and surrounding each block, (2) a decrease in the ferric-ferrous ratio of the basalt from the rim to the core of each block, and (3) a change in the alteration of olivine from iddingsite in the rim to serpentine in the core. The influence of meteoric water appears to have been to increase the oxygen fugacity in the rock adjacent to fractures through which superheated steam was escaping to the surface from below. These areas of the rock later became the rims of each block. In contrast, volatiles within the remainder of the rock, away from the fractures, were buffered by the rock and were at a much lower oxygen fugacity. Varying susceptibility of the secondary minerals formed during this stage of cooling to later chemical weathering resulted in the present structure.
The effects of mid-Phanerozoic environmental stress on bryozoan diversity, paleoecology, and paleogeography

Abstract Evidence of sustained environmental degradation associated with the end-Guadalupian, end-Permian, and end-Triassic extinctions has been inferred from numerous geochemical and sedimentological studies, but the long-term impacts of this extinction-associated stress on the evolutionary trajectories of marine invertebrates have not been explored. An examination of the diversity, extinction, paleoenvironmental range, and geographical distribution of marine stenolaemate bryozoans during the Permian to Jurassic interval provides striking new evidence of the taxonomic and ecological influence of these mid-Phanerozoic extinctions on one of the most abundant components of the Paleozoic Fauna. Elevated bryozoan extinction rates during the Late Permian and Late Triassic were coupled with major changes in their habitats. Bryozoans gradually disappeared from deep-water offshore settings during the Late Permian and from nearshore and offshore settings during the Late Triassic. Re-colonization of these environments in the wake of each crisis was delayed but coupled with increases in global generic diversity. The taxonomic effects of the end-Guadalupian extinction were milder than previously described, even though ecologically bryozoans were becoming restricted to nearshore settings. The end-Permian mass extinction remained the largest for bryozoans, drastically reducing global and assemblage generic diversity and triggering a permanent change in their paleoenvironmental preferences from nearshore to mid-shelf settings. The 285 Myr dominance of stenolaemate bryozoans ended during the Late Triassic when all but one order (Cyclostomata) became extinct, initiating a taxonomic switch between stenolaemate and gymnolaemate bryozoans. Moreover, spatio-temporal variations in the paleoenvironmental history of bryozoans imply that Late Permian and Late Triassic marine environmental instability resulted largely from some stressful deep-water phenomenon. High extinction rates in nearshore environments in the Late Permian provide a link between marine and terrestrial/atmosphere extinction-related perturbations.
Complex seasonal cycle of ecohydrology in the Southwest United States

[1] This study investigates the causes for, and distribution of, unimodal versus bimodal seasonal cycle of vegetation greenness in the Southwest United States using extensive site observations, climate data, satellite data, and the Lund-Potsdam-Jena (LPJ) vegetation model. Peak vegetation greenness is achieved in a clockwise manner across the Southwest, beginning in spring in the Sonoran Desert following winter rains, then in Utah-Colorado with snowmelt/summer rains, and finally in New Mexico–eastern Arizona with late summer monsoon rains. At high elevations, spring-summer snowmelt is critical for supplying the necessary soil moisture to trigger vegetation growth. A bimodal seasonal cycle of vegetation greenness is evident in satellite data and LPJ simulations across eastern Arizona and western New Mexico, characterized by peaks during late spring–early summer and late summer–early autumn. This bimodal green-up remains a pressing paradox for which many competing hypotheses exist. The mechanism for this seasonal pattern is demonstrated using LPJ and observational data and is found to deviate from the traditional pulse-reserve paradigm. This paradigm states that rainfall events in arid lands produce nearly immediate pulses of vegetation growth and accumulation of reserves but does not consider cold dormancy, time-lagged vegetation responses, or rainfall seasonality. The following soil moisture based mechanism for bimodal greening is proposed. The initial peak in vegetation greenness during late spring–early summer results from a break in cold dormancy and benefits from the gradual winter-long accumulation of deep soil moisture from weak synoptic rain events and snowmelt in colder regions. Limited precipitation and ongoing transpiration, from the initial vegetation greening, trigger a midsummer drying of the soil and a consequential minimum in vegetation activity. Later, pulses of monsoon rainfall in late summer–early autumn support the secondary greening, although significant runoff of brief, intense rainstorms and substantial soil evaporation limit moisture to the upper soil layers.
Transmission of herpes simplex virus from father to neonate

ALMOST ALL INFANTS with disseminated herpes simplex virus infections or H S V encephali t is are younger t han 4 weeks at the onset of symptoms. Al though the pathogenesis of neonata l HSV infect ions is not well understood, age per se appears to be an impor tan t risk factor in the development of disease. Evidence for this risk includes an age-related resistance to H SV infections in an imal models 1.2 and the clinical observation tha t infants older t han 4 weeks seldom develop disseminated H S V infections despite frequent exposure to persons with herpes labialis. I f age per se is an impor tan t factor in controll ing the severity of HSV infections, then exposures to persons with active HSV infeetions other than the mother may resul t in serious infections. Babyto-baby transmission of H S V is a l ready known t o r e s u l t in serious secondary infections. 34 This report documents the t ransmission of H S V f rom a fa ther to his infant son, resulting in disseminated H S V infection.
Narrow-band irradiation of a homologous series of chlorophenols on TiO2: charge-transfer complex formation and reactivity.

The goal of this research was to investigate the formation and reactivity of charge-transfer complexes (CTCs) among a homologous series of chlorophenols on TiO2. We previously showed that 2,4,5-trichlorophenol (245TCP) forms a CTC with Degussa P25, a commercial preparation of TiO2. Here, we probe how light energy influences reactivity and product formation. Slurries of P25 containing 245TCP were irradiated at 360, 400, 430, 480, and 550 nm. At each wavelength, the amount of transformation of 245TCP correlates to the diffuse-reflectance absorbance of a 245TCP/P25 system, supporting the CTC as the cause of reaction. In addition, polymeric products are formed only under wavelengths that excite the CTC, indicating a different reaction mechanism for the CTC than for bandgap excitation of TiO2. We also found a higher quantum efficiency for CTC reactivity than for bandgap activation of the catalyst, suggesting that the photocatalytic efficiency and selectivity can be improved for certain compounds by designing c...
Multi-path variational transition state theory for chemical reaction rates of complex polyatomic species: ethanol + OH reactions

Complex molecules often have many structures (conformations) of the reactants and the transition states, and these structures may be connected by coupled-mode torsions and pseudorotations; some but not all structures may have hydrogen bonds in the transition state or reagents. A quantitative theory of the reaction rates of complex molecules must take account of these structures, their coupled-mode nature, their qualitatively different character, and the possibility of merging reaction paths at high temperature. We have recently developed a coupled-mode theory called multi-structural variational transition state theory (MS-VTST) and an extension, called multi-path variational transition state theory (MP-VTST), that includes a treatment of the differences in the multi-dimensional tunneling paths and their contributions to the reaction rate. The MP-VTST method was presented for unimolecular reactions in the original paper and has now been extended to bimolecular reactions. The MS-VTST and MP-VTST formulations of variational transition state theory include multi-faceted configuration-space dividing surfaces to define the variational transition state. They occupy an intermediate position between single-conformation variational transition state theory (VTST), which has been used successfully for small molecules, and ensemble-averaged variational transition state theory (EA-VTST), which has been used successfully for enzyme kinetics. The theories are illustrated and compared here by application to three thermal rate constants for reactions of ethanol with hydroxyl radical—reactions with 4, 6, and 14 saddle points.
Distribution, diet, and energetic condition of age-0 walleye pollock (Gadus chalcogrammus) and pacific cod (Gadus macrocephalus) inhabiting the Gulf of Alaska

Abstract Walleye pollock (Gadus chalcogrammus) and Pacific cod (Gadus macrocephalus) are commercially and ecologically important species in Alaska waters. Little is known about their ecology after transitioning from larvae to free swimming fish until settlement to nursery habitats in the eastern Gulf of Alaska. Differences in the distribution, diet, body size, and energetic status between the eastern and central Gulf of Alaska were investigated during summer months to better understand regional and interspecific differences in life history and ecology. The composition of zooplankton prey in the diets of walleye pollock and Pacific cod inhabiting shelf waters was more varied relative to those inhabiting the slope and basin. Body condition and total energy content of Pacific cod was greater than walleye pollock, however total energy content increased with length at a similar rate for both species. Walleye pollock inhabiting continental slope waters had higher energy stores relative to those inhabiting the continental shelf and basin, indicating an energetic advantage for individuals remaining off the shelf during summer months or potentially the advection of fish with higher energy reserves off of the shelf. Previous studies have documented the importance of energy stores for surviving winter and future studies should focus on understanding the mechanisms influencing lipid storage and somatic growth for walleye pollock and Pacific cod inhabiting the eastern and central Gulf of Alaska.
Nondestructive Evaluation of the I-40 Bridge over the Rio Grande River

A nondestructive strength evaluation of the I-40 Bridge over the Rio Grande River in Albuquerque, N.M. was completed for the New Mexico Department of Transportation (NMDOT). The I-40 Bridge is a pr...
Groundwater Cleanup by in-situ Sparging. III. Modeling of Dense Nonaqueous Phase Liquid Droplet Removal

Abstract Microcomputer models for describing the removal of dispersed DNAPL (dense nonaqueous phase liquid) droplets from contaminated aquifers by air sparging are presented, and the dependence of cleanup times on the model parameters is explored. Diffusion transport is assumed to take place from spherical DNAPL droplets through a thick stagnant water layer in a porous medium to the advecting mobile water. Single sparging wells and single sparging curtains are modeled.
Origin of Foreign Direct Investment and Firm Performance: Evidence from Foreign Acquisitions of Chinese Domestic Firms

Using a newly created panel of domestic Chinese firms who receive foreign direct investment (FDI), this paper finds that Organisation of Economic Cooperation and Development (OECD)-acquired firms outperform those acquired by investors from Hong Kong, Macao and Taiwan (HMT). To control for possible endogeneity of the FDI decision, I employ propensity score matching combined with a difference-in-differences approach. The results indicate that relative to HMT-acquired firms, OECD-acquired firms experience significantly higher productivity in the initial year of acquisition and this productivity differential persists in subsequent years, reaching 27.8 per cent by the third year. Further, OECD-acquired firms exhibit higher profits, average wages and capital per worker compared to HMT-acquired firms. These results suggest that the origin of the foreign investor differentially affects target firm performance.
PIECEWISE APPROXIMATION FUNCTIONS AN EDUCATIONAL NOTE

This paper gives a survey of piecewise approximation functions. Aside from the use of dummy variables, little research has employed such functions. Piecewise functions permit the dependent variable of a functional relationship to take on different forms with respect to the independent variable on various subintervals of the domain of the independent variable. Three types of piecewise approximation functions are considered: dummy variables, piecewise linear regressions and cubic splines. The theoretical and empirical properties of such functions are discussed within the context of an illustrative example involving the increase in ridership over time on urban mass transit systems. Dummy variables take account of shifts in the structural relation in a discontinuous fashion. Piecewise regressions and cubic splines allow for structural shifts without discontinuities arising. Tests are performed to determine whether a linear, quadratic, or cubic piecewise continuous function should be employed. In addition a test is employed to see if structural change occurs in the functional relation at the shift points.
Phase-pulling and space-time complexity in an ac driven damped one-dimensional sine-gordon system

Abstract Using a collective-coordinate ansatz and multiple scale technique, we have studied the location and nature of breather instabilities, for a homogeneously driven, damped sine-Gordon system (on a finite line) in the nonlinear Schrodinger regime. We find that “phase-pulling” between the spatially localized breather, and the spatially extended uniform background is crucial.
EUV mask pattern defect printability

Mask defect specifications not only are needed to ensure quality masks for acceptable resist patterning on wafers, but also are utilized as a common goal for tool development, noticeably for mask inspection and repair. Defect specifications are generally determined by the allowable critical dimension (CD) changes from 'defect printability' experiments where a programmed defect mask (PDM) with intentionally placed defects is exposed in a stepper and the changes in resist CDs are measured. With the recent availability of extreme ultra-violet micro-exposure tools (EUV MET), a small field stepper with a numerical aperture (NA) of 0.3, 5X reduction and adjustable degrees of coherence, we are able for the first time to perform extensive studies of pattern defect printability for EUV masks with a high NA exposure tool. Such studies have investigated the defect impact to feature CDs for three different types of patterns: poly gate layer, contacts, and dense lines and spaces. This paper presents the experimental results and analysis of printability data collected under two illumination conditions, annular and dipole, on the MET with full focus and dose matrix (FEM). We have investigated as many as 10 types of defects designed on the PDM for each pattern layer. For each type of defect, a total of 15 sizes are coded on the PDM. With the consideration of limited resolution and line edge roughness of current EUV resists commonly used for EUV lithography development, the CDs under study were chosen in the range of about 40nm to 70nm. Extrapolations from these data are made to predict pattern defect specifications for smaller resist line features. Resist resolution is the main reason for the discrepancies between aerial image simulations and data presented in this paper.
Electrical Properties of Tin Dioxide Two-Dimensional Nanostructures

Tin dioxide is the most used material for gas sensing because its three-dimensional nanostructures and properties are related to the large surface exposed to gas adsorption. We propose the use of a two-dimensional nanostructure of SnO2 in the form of nanobelts; such newly achieved layers have been found to exhibit electrical properties that are similar to their three-dimensional counterpart but with the unique feature of being a pure crystal. Such a characteristic would guarantee long-term stability for the nanobelts, a condition which is not always met with three-dimensional nanostructures because of the occurrence of grain coalescence. In this framework, we developed an analytical approach to model the electrical properties of one-, two-, or three-dimensional nanostructures.