cssi/SciSciGPT-SciSciNet huggingface dataset:
SU-FF-I-33: T2-Weighted Prostate Imaging Using Echo-Planar Imaging at 3T

Purpose: T2‐weighting in fast spin echo (FSE) images is unavoidably affected by T1‐mixing due to stimulated echoes. The purpose of this research is to evaluate the feasibility of using a multishot echo‐planar (EPI) technique to image the prostate at 3 Tesla without an endorectal coil and to compare T2 quantification using EPI with that based off of FSE images.Method and Materials: All experiments were performed on a GE Signa 3 Tesla whole body scanner with an 8‐channel torso phased‐array coil. T2‐weighted images were acquired of a healthy volunteer at echo times (TEs) of 40, 80 and 110 ms with a multishot spin‐echo EPI. Other imaging parameters were: 32cm FOV, 16 shots, TR = 2000ms, acquisition matrix = 256×512, receiver bandwidth = ±250 kHz. FSE images were obtained of the same volunteer with TEs of 60, 120, and 180ms and these acquisition parameters: 16cm FOV, TR = 3900ms, acquisition matrix = 256×256, ETL = 16, bandwidth = ±32kHz. A total of eleven slices covering the entire prostate were collected using both techniques. Results: The EPI images showed few artifacts and were noted to provide better T2‐contrast than the FSE images. For a region‐of‐interest in the peripheral zone of the prostate, T2 values derived from FSE images (134±15 ms) are substantially larger than those based on EPI images (76±1 ms). This observation is consistent with the apparent lengthening of T2 due to T1 mixing in FSE images.Conclusion: Using EPI with high receiver bandwidth, our results indicate that high quality T2‐weighted images of the prostate can be obtained at 3T without an endorectal coil. T2‐weighted images by EPI provide pure T2‐contrast and possibly more accurate T2‐determination than conventional FSE images.
Thyroid disease in women

Thyroid diseases occur more commonly in women than men, in part because of the autoimmune nature of many thyroid disorders. Hypothyroidism, and thyroid nodules occur frequently in both pre- and postmenopausal women. Pregnancy is also associated with changes in thyroid function. The goal of this article is to review the current information on the pathophysiology and treatment of thyroid disorders which are common in women.
Interactions between bis(guanylhydrazones) and polyamines in isolated mitochondria.

Abstract 1. 1. The interactions of naturally occurring polyamines: putrescine, spermidine and spermine, with anticancer bis-guanylhydrazones: methylglyoxal-bis(guanylhydrazone) (MGBG) and 4,4′-diacetyldiphenylurea-bis(guanylhydrazone) (DDUG) were investigated at the level of mitochondrial membrane. 2. 2. The effects of bis-guanylhydrazones on intact rat liver mitochondria were readily prevented or reversed by polyamines and these interactions were also affected by the mictochondrial transmembrane potential. 3. 3. Magnesium cations enhanced the protective action of polyamines. The data indicate that competition exists between the essential anticancer bis(guanylhydrazones) and polyamines for low affinity negatively charged binding sites at the outer surface of inner mitochondrial membrane. 4. 4. The study of drug interactions was extended to the level of isolated tumor mitochondria from rat HTC hepatoma and muraine L1210 leukemia cells. 5. 5. A complicated pattern of interactions between the anticancer bis-guanylhydrazones and phenethylbiguanide was obtained.
Paragonimus ohirai Metacercariae in Crabs Collected along the Arakawa River in Tokyo, Japan

Brackish water crabs infected with Paragonimus ohirai metacercariae have been reported in various regions in Japan. However, infected crabs have not been identified in Tokyo. We therefore collected the crab, Chiromantes dehaani, between August 2002 and July 2003 from 12 locations along the Arakawa River that flows through Tokyo. Of the 922 captured crabs, 177 (19%) from 6 locations were infected with Paragonimus metacercariae. The prevalence of metacercariae at these 6 locations ranged from 5 to 89%. The number of metacercariae per infected crab ranged from 1 to 190, with an average of 13.1. The morphological features of the metacercariae and of adult worms recovered from test rats infected with metacercariae showed that the metacercariae in the infected crabs were P. ohirai Miyazaki, 1939. The ITS2 sequence data support this conclusion. This paper is the first description of P. ohirai infection of crabs in Tokyo.
Evaluation of readiness to transfer to adult healthcare: What about the well adolescent?

Abstract Background Understanding readiness to transfer from pediatric to adult healthcare is important for all youth; however, research and implementation guidelines in this area have emphasized youth seen in pediatric subspecialty settings. The purpose of this study was to develop an approach for evaluating transition readiness in a primary care setting, collect pilot data that examined the transition readiness of teens in that program, and implement assessments as part of clinical care. Method Forty boys and girls aged 12–22 were recruited from an adolescent medicine outpatient program in a large children’s hospital. The first 10 adolescents provided responses to questions and participated in cognitive interviewing. Questions changed minimally and responses from all 40 participants were combined. After the study visit, a researcher compared participant responses to electronic medical records and coded responses for accuracy. The survey consisted of 41 transition readiness items from previously published measures. Results The research team was able to develop a tool to assess transition readiness within a clinical setting. When administered to participants from that program, participants demonstrated poor transition readiness. Modifications were made based on participant feedback and implementation in the clinical setting. Clinicians were successful with administering transition readiness assessments. Conclusions It appears that even in youth who are generally well, transition readiness is low. Transition readiness assessments can be implemented in the primary care setting, and have been useful for guiding clinical care. Additional barriers and next steps will be discussed.
Persistent calcium current in rat suprachiasmatic nucleus neurons

The suprachiasmatic nuclei contain the primary circadian clock, and suprachiasmatic nuclei neurons exhibit a diurnal modulation of spontaneous firing rate. The present study examined the voltage-gated persistent Ca(2+) current, in acutely isolated rat suprachiasmatic nuclei neurons using a ramp-type voltage-clamp protocol. Slow triangular voltage-clamp commands from a holding potential of -85 mV to +5 mV elicited inward current (100-400 pA) that was completely blocked by Cd(2+). This current showed little or no hysteresis, and was identified as persistent Ca(2+) current. The threshold for persistent Ca(2+) current ranged between -60 and -45 mV, and it was maximal at about -8 mV. Nifedipine at 10-20 microM blocked 80-100%. To assess the role of persistent Ca(2+) current in the generation of spontaneous action potentials in both acutely isolated and intact suprachiasmatic nuclei neurons, the effect of Cd(2+) and nifedipine on firing rate was studied using on-cell recording. Application of Cd(2+) exerted a weak excitatory effect and nifedipine had no significant effect on the spontaneous firing rate of isolated suprachiasmatic nuclei neurons. In all intact suprachiasmatic nuclei neurons in slice preparations (n=15), Cd(2+) slowly inhibited spontaneous firing; in high-frequency firing cells (four of 15), a transient increase of firing rate preceded inhibition. No significant effect of nifedipine on firing rate of intact suprachiasmatic nuclei neurons was found. Therefore, persistent Ca(2+) current itself (as carrier of charge) does not appear to contribute significantly to spontaneous firing of suprachiasmatic nuclei neurons. A slowly developing inhibitory effect of Cd(2+) on spontaneous firing of intact suprachiasmatic nuclei neurons in slice preparations may be due to penetration of Cd(2+) through Ca(2+) channels, and its subsequent effect on intracellular mechanisms, while the transient increase of firing rate in high-frequency firing neurons is probably due to inhibition of Ca(2+)-activated K(+) current.
Comparing the Accuracy and Repeatability of On-Wafer Calibration Techniques to 110GHz

Many methods of making corrected S-Parameters measurements are available for on-wafer devices and circuits. This is a comparative study of calibration techniques, presented as most accurate and repeatable for making on-wafer measurements.
Epilepsia partialis continua as an atypical presentation of cat scratch disease in a young adult.

Cat scratch disease (CSD), caused by Bartonella henselae , is usually a self-limited illness transmitted from cats to humans as a result of a scratch or bite and is associated with lymphadenopathy, fever, fatigue, and sometimes papule at the inoculation site. Unusual presentations include transverse myelitis and encephalopathy. CSD encephalopathy usually occurs several weeks after the acute illness and may be heralded by seizures and status epilepticus. An 18-year-old right-handed previously healthy woman developed increasing difficulty speaking, which lasted several days and was followed by witnessed generalized tonic-clonic seizures. She was seen in another hospital, where a CT scan of the head was performed and showed no abnormalities. She was discharged but continued to have difficulties in speaking associated with twisting of her right lip angle. Subsequently, she had another generalized tonic-clonic episode followed by continuous right facial motor seizures that were difficult to control with antiepileptic drugs. Results of routine blood work, CSF analysis, and initial MRI of the brain were all normal. Multiple sessions …
Is oligohydramnios is postterm pregnancy associated with redistribution of fetal blood flow

Abstract OBJECTIVE: Our purpose was to determine whether postterm patients with oligohydramnios differ in their fetal and umbilical flow distributions from those with a normal volume of amniotic fluid. STUDY DESIGN: Pulsed-wave Doppler imaging was used prospectively to determine the resistance index in the fetal middle cerebral, renal, and umbilical arteries in 57 postterm (i.e., >41 weeks' gestation) pregnancies. Semiquantitative assessment of amniotic fluid volume was obtained by use of the ultrasonographically determined amniotic fluid index. RESULTS: Oligohydramnios (amniotic fluid index p CONCLUSION: Oligohydramnios was not associated with a major redistribution of blood flow in postterm patients, suggesting that the cause of oligohydramnios in these patients is related to birth weight rather than to renal perfusion.
Chemical potentials in ionic systems from Monte Carlo simulations with distance-biased test particle insertions

Abstract In this paper, we investigate sampling techniques for determination of chemical potentials of ionic systems based on distance-biased insertions of ion pairs. After a brief review of previous work in the area of calculation of chemical potentials and phase equilibria for ionic systems, we present conventional Monte Carlo calculations to illustrate that the standard test particle insertion or grand canonical algorithms become highly inefficient at the low temperatures for which phase coexistence occurs. A possible reason for the failure of conventional algorithms is their inability to adequately sample short interparticle distances that are dominant in the low density, low temperature region. We propose a distance-biased insertion method for determination of chemical potentials that preferentially samples short distances. Our biased procedure gives results in good agreement with standard insertions for the range of conditions for which standard insertions are valid, but does not improve the statistical uncertainty of the results or the range of temperatures and densities that can be studied.
Activity-dependent regulation of dendritic synthesis and trafficking of AMPA receptors

Regulation of AMPA receptor (AMPAR) trafficking is important for neural plasticity. Here we examined the trafficking and synthesis of the GluR1 and GluR2 subunits using ReAsH-EDT2 and FlAsH-EDT2 staining. Activity blockade of rat cultured neurons increased dendritic GluR1, but not GluR2, levels. Examination of transected dendrites revealed that both AMPAR subunits were synthesized in dendrites and that activity blockade enhanced dendritic synthesis of GluR1 but not GluR2. In contrast, acute pharmacological manipulations increased dendritic synthesis of both subunits. AMPARs synthesized in dendrites were inserted into synaptic plasma membranes and, after activity blockade, the electrophysiological properties of native synaptic AMPARs changed in the manner predicted by the imaging experiments. In addition to providing a novel mechanism for synaptic modifications, these results point out the advantages of using FlAsH-EDT2 and ReAsH-EDT2 for studying the trafficking of newly synthesized proteins in local cellular compartments such as dendrites.
C∗-algebras of multiplication operators on Bergman spaces

Soit Ω un domaine borne dans Cν, soit A 2 (Ω; μ) l'espace de Bergman de toutes les fonctions analytiques sur Ω qui sont de carre integrable par rapport a la mesure volumetrique μ, et soit C*(Ω) la C*-algebre engendree par les operateurs de multiplication par les fonctions coordonnee sur Ω. On etudie les proprietes de C*(Ω)
Reliability Allocation for Networks and Systems

The work here is motivated by a problem in engineering design, namely, the allocation of reliability to the subsystems of a system, or to the nodes of a network. Allocation problems in reliability have been considered before, but the focus has been on allocating redundancy rather than reliability. Attempts at the latter topic suffer from a drawback, namely, that component interdependencies have not been considered. Here we overcome this drawback, and then provide a foundation for addressing a class of optimization problems in reliability. This boils down to finding the fixed points of a function in a unit square. For this we use results from probability on the crossing properties of star-ordered distributions. We illustrate our approach by considering series, parallel, and bridge-structured networks. In the latter two cases, we are able to show that an optimal allocation of reliability could lead to system collapsibility, i.e., a simplification of the system's architecture. For the case of series systems with dependent life lengths, we observe the result that independence when incorrectly assumed could result in an overallocation of reliability.
Cross-National Sources of Health Inequality: Education and Tobacco Use in the World Health Survey

The spread of tobacco use from the West to other parts of the world, especially among disadvantaged socioeconomic groups, raises concerns not only about the indisputable harm to global health but also about worsening health inequality. Arguments relating to economic cost and diffusion posit that rising educational disparities in tobacco use—and associated disparities in health and premature mortality—are associated with higher national income and more advanced stages of cigarette diffusion, particularly among younger persons and males. To test these arguments, we use World Health Survey data for 99,661 men and 123,953 women from 50 low-income to upper-middle–income nations. Multilevel logistic regression models show that increases in national income and cigarette diffusion widen educational disparities in smoking among young persons and men but have weaker influences among older persons and women. The results suggest that the social and economic patterns of cigarette adoption across low- and middle-income nations foretell continuing, and perhaps widening, disparities in mortality.
Venular constriction of submucosal arterioles induced by dextran sodium sulfate.

Background: Leukocyte and platelet adherence in postcapillary venules has been speculated to induce constriction of closely paired arterioles. This mechanism was investigated in the current study, in a model of intestinal inflammation induced by dextran sodium sulfate (DSS; 5,000 molecular weight). Methods: Closely paired, parallel arterioles and venules in the submucosa of the mouse intestine were observed using fluorescent intravital microscopy. Arterioles in control mice were compared to arterioles in mice given 5% DSS in drinking water for 11 days. Results: DSS induced an inflammatory response in which fluorescently labeled leukocytes and platelets were observed adhering to venules. Arterioles constricted and flow decreased significantly when the arterioles were paired with venules having adherent leukocytes and platelets, although the decreases in flow and diameter appeared to be more dependent on platelet than leukocyte adherence. No significant constriction was observed in arterioles paired with venules having minimal platelet adherence. Inhibition of thromboxane with 100 mg/kg ozagrel induced a significant dilation of arterioles in DSS mice that was absent in control mice. Conclusion: The results are consistent with a proposed mechanism in which thromboxane constricts submucosal arterioles when the arterioles are closely paired with platelet-bearing venules in DSS-induced inflammation.
High-temperature elastic moduli of bulk nanostructured n- and p-type silicon germanium

Resonant ultrasound spectroscopy (RUS) has been used to measure the elastic moduli of $n$- and $p$-type doped polycrystalline bulk nanostructured silicon germanium alloys at elevated temperatures. A direct contact RUS transducer system with a working temperature range up to 900 K was successfully constructed for these measurements. For higher temperatures (up to 1300 K), we employed a traditional buffer rod RUS system. Experimental results show the Young's and shear moduli of $p$-type SiGe alloys monotonically decrease with increasing temperatures in the 300--1200 K range. The $n$-type samples show a marked stiffening beginning at 675 K which does not repeat upon cooling or subsequent reheating. We attribute the stiffening of the $n$-type samples to the thermally activated precipitation of the phosphorous dopant. Electrical resistivity and Seebeck coefficient data are also presented for both types of SiGe which support this conclusion.
The Viscosity of Natural and Remade Milk

Summary The relation of viscosity to the total solids is shown by means of the expression V − 1 T . S . in which V = Time of flow of milk × specific gravity of milk Time of flow of water × specific gravity of water and T.S. = total solids expressed as parts by weight of milk solids per gram of fluid milk. For a given number of samples the values for V − 1 T . S . for natural pasteurized milk varied from 5.68 to 7.18 and for remade milk from 6.26 to 12.60 at 25°C. The figures for mixtures containing 15 to 30 per cent of remade milk varied from 5.96 to 8.37. When the viscosity was determined at 15°C. the figures varied from 7.20 to 7.67 for natural pasteurized milk, from 6.70 to 8.06 for market milk and from 7.13 to 16.63 for remade milk. The viscosity of milk as determined is, to a certain extent, dependent upon the temperature at which the milk has been held. The viscosity is decreased slightly by pasteurization at 62−65°C. for 30 minutes, but considerably increased by heating at 75−80°C. for the same length of time. Homogenization at a high pressure has considerable effect on the viscosity, while the emulsor has little or no effect. By means of a high speed centrifuge it was found possible to throw out milk solids from both natural and remade milk to such an extent as to lower the values for V − 1 T . S . as compared with the values for the original milk. The sediment obtained from remade milk differed in quantity and character from that of natural milk.
Nonmontmorillonitic Composition of Some Bentonite Beds

Although the wide range of minerals resulting from alteration of tuffaceous rocks under hydrothermal and weathering conditions is well known, the extent of variation in composition of discrete bentonite beds subjected only to normal diagenesis and compaction is perhaps less well known. Three bentonite samples from the Atoka Formation of Pennsylvanian age are predominantly mixed-layer illite-montmorillonite with subordinate kaolinite. Most bentonites in the Fierre Shale of Late Cretaceous age are entirely montmorillonite, but a few contain some kaolinite; one is predominantly kaolinite; some also contain appreciable interlayer Al(OH)3 or Mg(OH)2 forming a mixed-layer montmorillonite-chlorite clay; several are composed of considerable clinoptilolite, and one is largely phillipsite. Bentonite beds in the Carmel Formation of Middle and Late Jurassic age differ among themselves in composition; in a few, illite is the dominant clay; in others, mixed-layer chlorite-montmorillonite-illite in different proportions is the dominant clay; kaolinite is common and makes up nearly half of one sample. A rhyolite tuff near Denver, Colorado, has been altered to halloysite. Reasons for variation in the composition of these bentonites are only partly understood.
Using Web-Based Participatory Mapping to Investigate Children’s Perceptions and the Spatial Distribution of Outdoor Play Places

This study examines where children play in a city undergoing rapid urbanization and how they perceive these places. Three hundred twenty-seven children aged 10 to 13 in Yantai, China engaged in web-based participatory mapping to identify play places and bad places and to provide perceptions about these places. RESULTS showed that play places were clustered around existing public places, and children in the periphery of the city traveled longer distances to reach play places. In addition, play places and bad places overlapped, indicating that children had concerns about existing play spaces. Children mentioned destination, social interaction, and proximity to home as reasons for playing in a place, whereas risk of traffic and strangers, low air quality, and unfamiliarity were perceived as barriers. We conclude that the web-based participatory mapping tool we used is a promising approach to empower children as active researchers, and the knowledge about children's environmental perception can support evidence-based design and planning. Language: en
Antibiotrophs: The complexity of antibiotic-subsisting and antibiotic-resistant microorganisms

Widespread overuse of antibiotics has led to the emergence of numerous antibiotic-resistant bacteria; among these are antibiotic-subsisting strains capable of surviving in environments with antibiotics as the sole carbon source. This unparalleled expansion of antibiotic resistance reveals the potent and diversified resistance abilities of certain bacterial strains. Moreover, these strains often possess hypermutator phenotypes and virulence transmissibility competent for genomic and proteomic propagation and pathogenicity. Pragmatic and prospicient approaches will be necessary to develop efficient therapeutic methods against such bacteria and to understand the extent of their genomic adaptability. This review aims to reveal the niches of these antibiotic-catabolizing microbes and assesses the underlying factors linking natural microbial antibiotic production, multidrug resistance, and antibiotic-subsistence.
Outcomes differ in patients who undergo immediate intraoperative revision versus patients with delayed postoperative revision of residual lesions in congenital heart operations.

Objectives In a previous study of infants less than 6 month old, we found that delayed revision of residual lesions resulted in worse patient outcomes compared with intraoperative revision. We explored a larger cohort to determine if this finding persisted. Methods A prospective cohort followed from index surgery to discharge from January 2011 to September 2013 were divided into 4 groups: (1) intraoperative revisions (IO) of residual lesions, (2) delayed postoperative revision (PO) of residual lesions during the same hospital stay, (3) both intraoperative and delayed (BOTH) revision of residual lesions, (4) no intraoperative or postoperative revision (NO). Linear and logistic regression analyses were used to compare outcomes of postoperative hospital length of stay, postoperative adverse events (AE), hospital costs, and mortality, after adjusting for age, prematurity, presence of extracardiac anomalies, and RACHS-1 (Risk Adjustment for Congenital Heart Surgery-1) risk category known to affect outcomes. Results Of the 2427 patients discharged after a congenital cardiac operation, 1886 were eligible for this study after exclusion of adults, procedures performed off cardiopulmonary bypass, and transplants and assist devices. On multivariable modeling adjusting for other significant patient factors, the NO group fared better than the other 3 groups. The IO group had significantly lower postoperative length of stay, AE rate, and hospital costs compared with the PO and BOTH groups, but showed no significant differences in mortality. Conclusions Intraoperative correction of residual lesions results in shorter length of stay, and lower postoperative AE and costs compared with delayed postoperative revision of residual lesions.
Electric-field-induced dichroism of the V− center in MgO

Abstract Electric-field-induced alignment of V− centers in MgO crystals has been monitored by the ensuing dichroism in the 2.3 eV optical absorption band. The effective electric dipole moment is μ = 3.4±0.4 e A , and the centers respond freely to the applied fields even at liquid-helium temperatures. The optical excited state is found to be incompatible with a localized-atomic-orbital description.
Information architecture: blueprints for the Web

Information Architecture: Blueprints for the WebChristina WodtkeNew Riders, Indianapolis, 2003ISBN 0-7357-1250-6 $29.99
Plasmonics and nanoantennas for infrared detectors

Detectors that take full advantage of the energy confinement offered by surface waves could have significant performance advantages in dark current and optical functionality. We use a subwavelength patterned metal nanoantenna structure to convert incoming plane waves to these surface waves.
Self-Adaptive Tolling Strategy for Enhanced High-Occupancy Toll Lane Operations

In this paper, a self-adaptive tolling strategy (SATS) is developed for dynamically and systematically enhancing highoccupancy toll (HOT) lane system operations. This strategy enhances the overall system performance of both the HOT and general purpose (GP) lanes by better utilizing the HOT lane capacity while maintaining high speed and/or high travel-time reliability for HOT lane traffic when GP lanes are congested. To formulate SATS, the Lighthill-Whitham-Richards kinematic wave model is used to characterize HOT lane traffic flow evolution, and the unilateral Laplace transform is used to convert the system representation from the time domain to the frequency domain. Then, an adaptive tolling controller is designed with both the proportional and integral control components. Real-time traffic measurements, including lane occupancy, average speed, and flow rate, are utilized for toll rate calculations. Following a dual-phase control scheme, the appropriate flow rate for HOT lane utilization is computed, and the corresponding toll is estimated backward. To examine the effectiveness of the proposed tolling strategy, microscopic traffic simulation experiments are conducted using VISSIM. The experiment results demonstrate that the proposed tolling strategy performs reasonably well in improving the overall operations of HOT lane systems under various traffic conditions.
Use of a gaseous electrical discharge to induce fluorescence in organic compounds separated by thin-layer chromatography

Abstract It has been found that a simple gaseous electrical discharge can induce visible fluorescence in a variety of organic compounds separated on silica gel thin-layer chromatoplates. Exposure times ranging from 5 sec to 5 min are ample to detect submicrogram quantities with the unaided eye. The method is simple and convenient, and appears to have broad applicability to a wide variety of organic compounds. It is anticipated that this procedure will lend itself to sensitive quantitation by the use of spectrofluorimetric instrumentation.
Quantitation of enantiomers of r-7,t-8,9,c-10-tetrahydroxy-7,8,9,10-tetrahydrobenzo[a]-pyrene in human urine: evidence supporting metabolic activation of benzo[a]pyrene via the bay region diol epoxide

Benzo[a]pyrene (BaP), a potent polycyclic aromatic hydrocarbon carcinogen, is widely distributed in the human environment. All humans are exposed to BaP through the diet and contact with the general environment; cigarette smokers have higher exposure. An important pathway of BaP metabolism proceeds through formation of diol epoxides including the 'bay region diol epoxide' 7R,8S-dihydroxy-9S,10R-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene [BaP-(7R,8S)-diol-(9S,10R)-epoxide] and the 'reverse diol epoxide' 9S,10R-dihydroxy-7R,8S-epoxy-7,8,9,10-tetrahydrobenzo [a]pyrene [BaP-(9S,10R)-diol-(7R,8S)-epoxide]. The bay region diol epoxide is considered a major ultimate carcinogen of BaP based on studies in cell culture and laboratory animals, but the available data in humans are less convincing. The bay region diol epoxide and the reverse diol epoxide react with H2O to produce enantiomeric BaP-tetraols that are excreted in the urine. We used chiral stationary-phase high-performance liquid chromatography and gas chromatography-negative ion chemical ionisation-tandem mass spectrometry to quantify these enantiomeric BaP-tetraols in the urine of 25 smokers and 25 non-smokers. The results demonstrated that the BaP-tetraol enantiomer representing the carcinogenic bay region diol epoxide pathway accounted for 68±6% (range 56-81%) of total BaP-tetraol in smokers and 64±6% (range 46-78%) in non-smokers. Levels of the major BaP-tetraol enantiomer decreased by 75% in smokers who quit smoking. These data provide convincing evidence in support of the bay region diol epoxide mechanism of BaP carcinogenesis in humans.
Decontamination of Radionuclides from Concrete by Microwave Heating. I: Theory

The paper analyzes a proposed scheme of decontamination of radionuclides from concrete structures, in which rapid microwave heating is used to spall off a thin contaminated surface layer. The analysis is split in two parts: (1) the hygrothermal part of the problem, which consists in calculating the evolution of the temperature and pore pressure fields, and (2) the fracturing part, which consists in predicting the stresses, deformations and fracturing. The former is assumed to be independent of the latter, but the latter is coupled to the former. The heat and moisture transfer governing the temperature and pore pressure fields induced by the decontamination process is analyzed using an improved form of Bazant and Thonguthai’s model for heat and moisture transfer in concrete at high temperatures. The rate of the distributed source of heat due to the interaction of microwaves with the water contained in concrete is calculated on the basis of the standing wave normally incident to the concrete wall. Since the microwave time period is much shorter than the time a heating front takes to propagate over the length of microwave, and since concrete is heterogeneous, the ohmic power dissipation rate is averaged over both the time period and the wavelength. The reinforcing bars parallel to the surface are treated as a smeared steel layer. The recently developed microplane model M4 serves as the constitutive model for nonlinear deformation and distributed fracturing of concrete. Application of the present model in numerical computations is relegated to a companion paper which follows.
Monoclinic phase in PZT: order parameter and phase transition from Tetragonal Phase

A solution of the Lagrange–Euler equations for the order parameter–the electric polarisation vector P–which describes the monoclinic phase in PZT is found exactly in this article for the Gibbs free energy expansion done for the cubic phase up to the sixth–order in the order parameter. The phase transition from the tetragonal phase to the monoclinic phase in materials of the PZT type may be described within the Landau theory of phase transitions used by Haun and co-workers. The phase transition is found to be of the first order in general. The order parameter in the parameter space is two dimensional: the amplitude A and the angle. The PZT material has values of expansion coefficients in the Gibbs free energy such that the exact solution for description of the monoclinic phase is a metastable state. We may conclude then that the monoclinic phase exists in PZT due to higher than sixth-order terms in the Gibbs free energy expansion which are present due to high anharmonicity present in this material.
Coliphages and indicator bacteria in Boston Harbor, Massachusetts

Surface water was tested for two bacterial and two coliphage indicators of fecal pollution at four sites in Boston Harbor, MA over 1 year. Of 108 samples tested, somatic coliphages, fecal coliforms, enterococci, and F-specific phages were present in 107, 105, 73, and 58 water samples, respectively. The means of all samples, per 100 mL, were 195.6 pfu (range: 0-1833) for somatic coliphages, 101.3 cfu (0-2670) for fecal coliforms, 20.0 pfu (0-261) for F-specific phages, and 3.1 cfu (0-32) for enterococci. Somatic coliphages and fecal coliforms were more prevalent indicators of fecal pollution than enterococci and F-specific phages. No indicator correlated well with any of the others. No statistically significant difference in phage numbers was found between samples taken in summer and winter. No correlation was found between salinity and any indicator. There was no increase in counts of any indicator due to localized input from two marinas.
The response of interest rates to unemployment rate announcements: Is there a natural rate of unemployment?☆

Abstract This paper shows that there is a response of interest rates to announcements of unexpected changes in the unemployment rate. Overall, in response to an unexpectedly low unemployment rate announcement, interest rates rise and the dollar appreciates against three major currencies. This indicates that the real rate is responding to these announcements in general. This response differs depending on whether the current level of unemployment is above but near 5.9% or below that rate. Below 5.9%, there is a significant increase in the response of interest rates to unemployment surprises which is most likely a change in inflationary expectations. As such, 5.9 % appears to be the financial markets' estimate of the natural rate of unemployment. There is an anomalous relationship between unemployment surprises and interest rates when the unemployment rate is above, but near 5.9%. In this region, longer term interest rates fall in response to an unexpected decrease in unemployment.
Instability of multi-layer fluid configurations in the presence of time-dependent accelerations in a microgravity environment

The increasing number of research opportunities in a microgravity environment will benefit not only fundamental studies in fluid dynamics, but also technological applications such as those involving materials processing. In particular, fluid configurations which involve fluid-fluid interfaces would occur in a variety of experimental investigations. This work investigates the stability of a configuration involving fluid-fluid interfaces in the presence of a time-dependent forcing. Both periodic (g-jitter) and nonperiodic accelerations are considered. The fluid configuration is multilayered, and infinite in extent. The analysis is linear and inviscid, and the acceleration vector is oriented perpendicular to each interface. A Floquet analysis is employed in the case of the periodic forcing. In the problem of nonperiodic forcing, the resulting system of equations are integrated in time. Specific nondimensional parameters appear in each problem. The configuration behavior is investigated for a range of parameter values.
Hydraulic and flood-loss modeling of levee, floodplain, and river management strategies, Middle Mississippi River, USA

In this investigation, four scenarios were used to quantify the balance between the benefits of levees for flood protection and their potential to increase flood risk using Hazards U.S. Multi-Hazard flood-loss software and hydraulic modeling of the Middle Mississippi River (MMR). The goals of this study were (1) to quantify the flood exposure under different flood-control configurations and (2) to assess the relative contributions of various engineered structures and flood-loss strategies to potential flood losses. Removing all the flood-control structures along the MMR, without buyouts or other mitigation, reduced the average flood stages between 2.3 m (100-year flood) and 2.5 m (500-year), but increased the potential flood losses by $4.3–6.7 billion. Removing the agricultural levees downstream of St. Louis decreased the flood stages through the metro region by ~1.0 m for the 100- and 500-year events; flood losses, without buyouts or other mitigation, were increased by $155 million for the 100-year flood, but were decreased by $109 million for the 500-year flood. Thus, agricultural levees along the MMR protect against small- to medium-size floods (up to the ~100-year flood level) but cause more damage than they prevent during large floods such as the 500-year flood. Buyout costs for the all the buildings within the 500-year floodplain downstream of urban flood-control structures near St. Louis are ~40% less than the cost of repairing the buildings damaged by the 500-year flood. This suggests large-scale buyouts could be the most cost-effective option for flood loss mitigation for properties currently protected by agricultural levees.
Autologous tissue-engineered trachea with sheep nasal chondrocytes.

Abstract Objective: This study was designed to evaluate the ability of autologous tissue-engineered trachea shaped in a helix to form the structural component of a functional tracheal replacement. Methods: Nasal septum were harvested from six 2-month-old sheep. Chondrocytes and fibroblasts were isolated from tissue and cultured in media for 2 weeks. Both types of cells were seeded onto separate nonwoven meshes of polyglycolic acid. The chondrocyte-seeded mesh was wound around a 20-mm-diameter × 50-mm-long helical template and then covered with the fibroblast-seeded mesh. In 2 separate studies the implants were placed either in a subcutaneous pocket in the nude rat (rat tissue-engineered trachea) or in the neck of a sheep (sheep tissue-engineered trachea). Rat tissue-engineered tracheas were harvested after 8 weeks and analyzed by means of histology and biochemistry. Sheep tissue-engineered tracheas were harvested from the neck at 8 weeks and anastomosed into a 5-cm defect in the sheep trachea. Results: Sheep receiving tissue-engineered trachea grafts survived for 2 to 7 days after implantation. Gross morphology and tissue morphology were similar to that of native tracheas. Hematoxylin-and-eosin staining of rat tissue-engineered tracheas and sheep tissue-engineered tracheas revealed the presence of mature cartilage surrounded by connective tissue. Safranin-O staining showed that rat tissue-engineered tracheas and sheep tissue-engineered tracheas had similar morphologies to native tracheal cartilage. Collagen, proteoglycan, and cell contents were similar to those seen in native tracheal tissue in rat tissue-engineered tracheas. Collagen and cell contents of sheep tissue-engineered tracheas were elevated compared with that of normal tracheas, whereas proteoglycan content was less than that found in normal tracheas. Conclusions: This study demonstrated the feasibility of recreating the cartilage and fibrous portion of the trachea with autologous tissue harvested from single procedure. This approach might provide a benefit to individuals needing tracheal resection. J Thorac Cardiovasc Surg 2002;123:1117-84.
Cow's milk protein‐specific IgE concentrations in two age groups of milk‐allergic children and in children achieving clinical tolerance

Background IgE-mediated cow's milk protein allergy (CMPA) is usually outgrown in children by the age of 3 years. The immunological responses to cow's milk proteins in children who achieve tolerance, in comparison with those who remain allergic, however, are not well described. Objective To compare the level of cow's milk protein-specific IgE among children with documented CMPA under the age of 3 years, another group over the age of 9 years (persistent allergy), and in another group of children in whom clinical tolerance developed. Methods Stored sera from children with CMPA were analysed for IgE antibodies specific for whole cow's milk, casein, whey, α-lactalbumin (ALA), β-lactoglobulin (BLG), and bovine serum albumin (BSA) using the Pharmacia CAP System FEIA. Results Within each group of CMPA children, the concentration of specific IgE antibody to casein proteins was not significantly different from that to whey proteins. However, children in the group with CMPA over 9 years of age had significantly greater concentrations of whole milk (P = 0.02) and casein-specific (P = 0.04) IgE antibodies compared with the group of children with CMPA under age 3 years. Children under the age of 3 years had a higher median concentration of casein-specific IgE (20.2 vs. 5.5, P = 0.04) than another group of 11 children (mean age 3.5 years), who later lost their milk allergy. Out of 16 children who lost sensitivity to milk, 75% had milk-specific IgE levels below 14.3 kUA/L (median, 1.3 kUA/L). Conclusions Although a dominant allergenic milk protein fraction was not identified within either of the two age groups, those with persistent CMPA over age 9 years had significantly elevated levels of milk and casein-specific IgE compared with younger children with CMPA.
Witnessing violence: making the invisible visible

In his novel of Black life circa the 1950s, Invisible Man, Ralph Ellison laid bare the wasteful, destructive societal consequences of racism. At the close of the 20th century, we are faced with the phenomenon of another social problem, likewise unresolved and likely to haunt us similarly: urban violence. Following Ellison's example, this paper seeks to explore the impact of violence's stark invisibility by discussing a research strategy that better explains the terrifying phenomenon of violence. In order to comprehend the totality of violence, macro- and micro-level variables have to be introduced into the research design and measured over time. Therefore, research might best address violence if it was designed to include variables of poverty and racism, and was more inclusive of research from a broader range of scientific disciplines.
Depletion of short-wave irradiance at the ground by particles suspended in the atmosphere

Abstract Changes in concentration of those atmospheric constituents which contribute to the planetary albedo can give rise to climatic alterations. Suspended particles in the atmosphere contribute to the albedo by virtue of their light-scattering power. This paper presents a mathematical model of the effect of particulate loading on daily totals of irradiance at the ground at various latitudes and seasons, under the assumptions of: (a) Rayleigh scattering by the gaseous constituents of the atmosphere, and (b) Mie scattering by a uniform layer of polydisperse particles having a power-law size-distribution function. These computations show that substantial depletions of irradiance can result from moderate to heavy particulate loadings, and that an increase in man-made particulate emissions by a factor of 50 or more could give rise to a general cooling of serious magnitude.
Recent advances in the application of gene therapy to human disease

PURPOSE : To review the recent advances in the application of genetic modification strategies to the therapy of human diseases for which a molecular defect is known. METHODS : A computerized data bank search, the minutes of the National Institutes of Health (NIH) Recombinant DNA Advisory Committee published in the Federal Record, and reports of human clinical trials were used as data sources for this review. Clinical trials included in this review were published in the literature or approved by the NIH Recombinant DNA Advisory Committee. STUDY SELECTION : Evaluations of the efficacy of genetic modification strategies in clinical trials in human and in animal models are summarized. The design and outcome of the genetic modification strategies employed are reviewed for 16 marking trials, 16 gene replacement trials for molecular deficiency diseases, 3 chemoprotection and 4 chemotherapy sensitization trials, 11 cancer vaccine trials, 2 antisense oligonucleotide trials, and 3 molecular immunotherapy trials. DATA SYNTHESIS : The marking trials have shown that residual leukemia cells in the infused autologous marrow can contribute to relapse following autologous bone marrow transplants. The use of genetic modification for the replacement of missing or deficient genes in severe combined immunodeficiency, familial hypercholesterolemia, and cystic fibrosis has been associated with encouraging results so far. Clinical genetic therapy trials involving cancer vaccines, antisense oligonucleotides, adoptive immunotherapy with genetically modified T cells, delivery vectors containing interleukin-1 receptor inhibitor for arthritis, replacement strategies for storage diseases, and genetic suppression of human immunodeficiency viral replication are just commencing. CONCLUSIONS : The clinical application of genetic modification techniques has thus far been successful in the beginning phases of this field. These early results suggest that continuation of gene therapy trials designed to correct the molecular changes that lead to disease states in humans is warranted. Evaluation of such clinical trials in the future may be based on the analysis of assays for short-term surrogate endpoints, as well as on the therapeutic outcomes of the trial, such as survival or remission.
Reduction in obesity-related comorbidities: is gastric bypass better than sleeve gastrectomy?

Background Bariatric surgery is currently the most effective treatment for morbid obesity. It provides not only substantial weight loss, but also resolution of obesity-related comorbidities. Laparoscopic sleeve gastrectomy (LSG) has rapidly been gaining in popularity. However, there are limited data on the reduction of obesity-related comorbidities for LSG compared to laparoscopic Roux-en-Y gastric bypass (LRYGB). The aim of this study was to assess the effectiveness of laparoscopic LSG versus LRYGB for the treatment of obesity-related comorbidities.
A survey of past obstetrics and gynecology research fellows.

OBJECTIVE: To survey obstetrician-gynecologist-scientists to determine factors that enhanced or hindered research careers. METHODS: A pretested mail survey was sent to 107 obstetrician-gynecologists who had received research fellowship awards from professional organizations during the years 1971-1999. Demographic information along with face-value, forced-choice and yes-no questions as well as those asking for a single response using a Likert-type scale were requested. Two open-ended questions were also asked. The questionnaire was designed to obtain at least a 60% return. RESULTS: A 62.2% return demonstrated that 92% of this group of former fellows holds academic positions. Twenty-four percent of respondents had no research mentors in the first 5 years after fellowship, and 58% had or have National Institutes of Health grant awards, with an average of two grants. The majority believed they did not have adequate time to conduct research, stating that 80% or more time was necessary for a successful research career. CONCLUSION: Career success of the respondents is variable and is related to mentors, time allocated to research, and funding. The obstetrics and gynecology specialty must find ways to provide increased mentoring and time allocation to encourage funding opportunities.