cssi/SciSciGPT-SciSciNet huggingface dataset:
Implications of anthropogenic river stage fluctuations on mass transport in a valley fill aquifer

[1] In humid regions a strong coupling between surface water features and groundwater systems may exist. In these environments the exchange of water and solute depends primarily on the hydraulic gradient between the reservoirs. We hypothesize that daily changes in river stage associated with anthropogenic water releases (such as those from a hydroelectric dam) cause anomalous mixing in the near-stream environment by creating large hydraulic head gradients between the stream and adjacent aquifer. We present field observations of hydraulic gradient reversals in a shallow aquifer. Important physical processes observed in the field are explicitly reproduced in a physically based two-dimensional numerical model of groundwater flow coupled to a simplistic surface water boundary condition. Mass transport simulations of a conservative solute introduced into the surface water are performed and examined relative to a stream condition without stage fluctuations. Simulations of 20 d for both fluctuating river stage and fixed high river stage show that more mass is introduced into the aquifer from the stream in the oscillating case even though the net water flux is zero. Enhanced transport by mechanical dispersion leads to mass being driven away from the hydraulic zone of influence of the river. The modification of local hydraulic gradients is likely to be important for understanding dissolved mass transport in near-stream aquifer environments and can influence exchange zone processes under conditions of high-frequency stream stage changes.
Synaptic Augmentation Contributes to Environment-Driven Regulation of the Aplysia Siphon-Withdrawal Reflex

This research shows that short-term synaptic plasticity can play a critical role in shaping the behavioral response to environmental change. In Aplysia, exposure to turbulent environments produces a stable reduction in the duration of the siphon-withdrawal reflex (SWR) and the responsiveness of siphon motor neurons. Recovery takes >1 min after a brief (10 sec-5 min) exposure but <1 min after a long (10 min) exposure. Here we demonstrate that (1) in-turbulence and post-turbulence phases of regulation depend on different cellular processes and (2) the post-turbulence phase of regulation is mediated by augmentation (AUG), an activity-dependent form of short-term synaptic plasticity. In reduced preparations (tail, siphon, and CNS), we show that treatment with 100 microm d-tubocurarine has no effect on in-turbulence regulation but blocks up to 90% of post-turbulence regulation, indicating that these phases of regulation are mediated by distinct cellular process. We then show that (1) turbulence induces activity in L30 inhibitory interneurons, (2) this activation produces AUG that lasts 1 min after a brief exposure to turbulence, and (3) manipulations that attenuate L30 AUG also attenuate regulation after brief turbulence. We also found that long (10 min) exposures to turbulence do not produce a post-turbulence phase of regulation because L30 activity declines over the course of a long turbulence exposure, leading to the decay of AUG before turbulence offset. Our results demonstrate a specific behavioral function of AUG and show how interactions between cellular processes can confer temporal sensitivity in the network regulation of behavior.
Alterations in lipid composition of liver cell plasma membranes during development.

Liver plasma membranes of Swiss-Webster CFW mice ranging in age from 5 to 165 days were isolated employing a two-phase dextran/polyethylene glycol polymer system. Electron microscopy revealed low mitochondrial and microsomal contamination. Lipids were quantitatively extracted and subjected to two dimensional thin layer chromatography. Individual lipids were eluted and phosphorus was measured by the Malachite green method. Cholesterol was quantitated by the micro Lieberman-Burchard method and sphingolipids were quantitated fluorometrically with fluorescamine. During development, phosphatidylethanolamine levels decreased from 43.2% to 19.5% whereas phosphatidylcholine levels rose from 26.6% to 45.2%. The ratio of phospholipid/cholesterol remained essentially constant during development; but the sphingolipid/cholesterol and sphingolipid/phospholipid ratios increased from 0.75 to 1.79 and 0.11 to 0.34, respectively.
DNA Testing, Banking, and Genetic Privacy

With the advent of DNA analysis, there is a growing public impression that the answer to “Who am I?” may be found in our genes. Patricia Roche and George Annas write that we should be alert to the risks as well as the benefits of exploring our DNA and basing an understanding of who we are on genetic testing.
A gas chromatographic method for the analysis of lipoic acid in biological samples.

Abstract A method has been developed for the gas chromatographic analysis of lipoic acid in biological samples. The lipoic acid is released from the samples by acid hydrolysis in the presence of the internal standards 1,2-dithiolane-3-butyric acid and/or 1,2-dithiolane-3-caproic acid. After hydrolysis, the lipoic acid and the internal standards are extracted from the hydrolysate and converted into the S,S -dibenzylmethyl esters. Gas chromatographic analysis of this mixture completely separates each of the homolog derivatives from the lipoic acid derivative and allows for the quantitation of the lipoic acid in the sample. Samples containing more than ∼50 ng of lipoic acid can be easily assayed. Results are presented that show that the lipoic acid content of Escherichia coli depends on the carbon source used for its growth.
A new rust on Alyxia ruscifolia in queensland

Uromyces alyxiae var. australiensis is newly described on Alyxia ruscifolia, a species endemic to Australia, and compared with U. alyxiae var. alyxiae, previously described on A. olivaeformis, a species endemic to Hawaii.
Changes in Amino Acid Content of Acidified Sweet Potato Puree

The stability of nitrogenous substances in processed sweet potato puree was examined. Protein and nonprotein nitrogen (NPN) fractions were extracted from sweet potato puree adjusted to pH 4.2, treated with amylolytic enzymes and processed at 88°C to determine changes in amino acid concentrations over a 6-month period. Amino acid concentrations in the protein fraction were generally found to remain stable over the storage period. NPN amino acid concentration either remained stable or increased slightly with storage time. The results of this work indicate that there would be no appreciable loss of nitrogenous substances in sweet potato puree subjected to the conditions of the experiment.
Retrovirus-mediated gene transfer to cystic fibrosis airway epithelial cells: effect of selectable marker sequences on long-term expression

Retrovirus-mediated gene transfer offers the potential for stable long-term expression of transduced genes in host cells subsequent to integration of vector DNA into the host genome. Using a murine amphotropic retrovirus vector containing an interleukin-2 receptor (IL-2R) gene as a reporter and a neomycin phosphotransferase (neor) gene as a dominant selectable marker, we measured the efficiency of retrovirus-mediated gene transfer and the stability of transduced gene expression in a cystic fibrosis tracheal epithelial cell line (CFT1). The use of the IL-2R cell surface marker as a reporter of infection permitted both quantitation of vector gene expression and flow cytometric sorting of cells transduced with the vector. In initial studies, the optimal conditions for retrovirus-mediated gene transfer were determined. The presence of a polycation was required for optimal transduction efficiency. The efficiency of infection of CFT1 cells was increased by repetitive exposure to virus such that it was possible to transduce approximately 80% of the cells following three successive daily exposures. The long-term stability of expression of the non-selected IL-2R gene was also evaluated. A slow decline in the percentage of cells expressing IL-2R was seen with cells that were maintained under constant selection pressure for expression of the neor gene, which was expressed from an internal promoter. Similar results were obtained when cultures were selected initially for neor gene expression and maintained without selection thereafter. In contrast, stable expression was observed in CFT1 cells for at least one year following multiple infections in the absence of G418 selection. In conclusion, (i) transduction of foreign genes into human airway epithelial cells using an amphotropic retrovirus vector can be highly efficient in the presence of appropriate polycations and multiple exposures; and (ii) stable expression of a non-selected gene in these epithelial cells is better maintained without selection.
PILOT STUDY OF LATEWOOD-WIDTH OF CONIFERS AS AN INDICATOR OF VARIABILITY OF SUMMER RAINFALL IN THE NORTH AMERICAN MONSOON REGION

The variability of the North American Monsoon System (NAMS) is important to the precipitation climatology of Mexico and the southwestern United States. Tree-ring studies have been widely applied to climatic reconstruction in western North America, but as yet, have not addressed the NAMS. One reason is the need for highly resolved seasonal dendroclimatic information. Latewood-width, the portion of the annual tree ring laid down late in the growing season, can potentially yield such information. This paper describes a pilot study of the regional summer precipitation signal in latewood-width from a network of five Pseudotsuga menziesii chronologies developed in the heart of the region of NAMS influence in Arizona, USA. Exploratory data analysis reveals that the summer precipitation signal in latewood is strong, but not equally so over the full range of summer precipitation. Scatter in the relationship increases toward higher levels of precipitation. Adjustment for removal of inter-correlation with earlywood-width appears to strengthen the summer precipitation signal in latewood-width. To demonstrate a possible application to climatic reconstruction, the latewood precipitation signal is modelled using a nonlinear model—a binary recursive classification tree (CT) that attempts to classify summers as dry or not dry from threshold values of latewood-width. The model identifies narrow latewood-width as an effective predictor of a dry summer. Of 14 summers classified dry by latewood-width for the period 1868–1992, 13 are actually dry by the instrumental precipitation record. The results suggest that geographical expansion of coverage by latewood-width chronologies and further development of statistical methods may lead to successful reconstruction of variability of the NAMS on century time scales. Copyright © 2001 Royal Meteorological Society
Biosynthesis of 3-hydroxy fatty acids, the pheromone components of female mallard ducks, by cell-free preparations from the uropygial gland.

Abstract Diesters of 3-hydroxy C 8 , C 10 , and C 12 acids, the female mallard duck pheromones, were found as the major products of the uropygial glands only during the breeding season. The 3-hydroxy acids were identified by mass spectrometry of the trimethylsilyl ethers of the methyl esters and of the diols derived from LiAlH 4 reduction of the hydroxy acids. A cell-free extract from the gland catalyzed conversion of dodecanoic acid to 3-hydroxydodecanoic acid which was identified by radio thin-layer and radio gas chromatographic analysis of the enzymic products as methyl-3-acetoxydodecanoate and as diacetate of the diol generated by LiAlH 4 reduction of the enzymic product. The enzymic introduction of the hydroxyl group at C-3 was catalyzed mainly by a 50,000 g pellet prepared from a 1000 g supernatant obtained from the cell-free extract. This reaction required ATP, CoA, and O 2 , and the CoA ester of the acid was more efficiently converted than the free acid to the 3-hydroxy acid. KCN at 1 m m and 50% CO did not inhibit the reaction. 3 H from 3 H 2 O was incorporated into 3-hydroxydodecanoic acid during the enzymic synthesis of this acid from dodecanoic acid. Mass spectrometry of the 3-hydroxy acid generated by the particulate fraction in the presence of H 2 18 O showed that 18 O was incorporated as expected from hydration of a Δ 2 double bond. From the above results it is tentatively concluded that peroxisomal acyl-CoA oxidase converts the acyl-CoA to the 2-enoyl-CoA which is hydrated to generate the 3-hydroxy acid.
Global geomagnetic field models for the past 3000 years: transient or permanent flux lobes?

PSVMOD1.0 is a compilation of globally distributed palaeodirectional data from archaeomagnetic artefacts, lava flows, and lake sediments at 24 sites evaluated at 100 year intervals from 1000 BC to AD 1800. We estimate uncertainty in these measures of declination and inclination by comparison with predictions from standard historical models in time–intervals of overlap, and use the 100–year samples and their associated uncertainties to construct a sequence of minimum structure global geomagnetic field models. Global predictions of radial magnetic field at the coremantle boundary (CMB), as well as inclination and declination anomalies at the Earth9s surface, provide an unprecedented view of geomagnetic secular variations over the past 3000 years, and demonstrate a consistent evolution of the field with time. Resolution of the models is poorest in the Southern Hemisphere, where only six of the 24 sites are located, several with incomplete temporal coverage. Low–flux regions seen in the historical field near the North Pole are poorly resolved, but the Northern Hemisphere flux lobes are clearly visible in the models. These lobes are not fixed in position and intensity, but they only rarely venture into the Pacific hemisphere. The Pacific region is seen to have experienced significant secular variation: a strong negative inclination anomaly in the region, like that seen in 0–5 Ma models, persists from 1000 BC until AD 1000 and then gradually evolves into the smaller positive anomaly seen today. On average between 1000 BC and AD 1800, the non–axial–dipole contribution to the radial magnetic field at the core–mantle boundary is largest in the north–central Pacific, and beneath Central Asia, with clear non–zonal contributions. At the Earth9s surface, average inclination anomalies are large and negative in the central Pacific, and most positive slightly to the east of Central Africa. Inclination anomalies decrease with increasing latitude. Average declinations are smallest in equatorial regions, again with strong longitudinal variations, largest negative departures are centred over Australia and Eastern Asia. Secular variation at the Earth9s surface is quantified by standard deviation of inclination and declination about their average values, and at the CMB by standard deviation in radial magnetic field. All three show significant geographical variations, but appear incompatible with the idea that secular variation in the Pacific hemisphere is permanently attenuated by greatly enhanced conductivity in D 00 beneath the region.
Macroscopic quantum tunneling in 1 μm Nb junctions below 100 mK

Abstract The transition probabilities out of the superconducting state of low current density 1 μm Nb Josephson junctions with capacitance
The Finite Element Method for Mechanics Analysis of Joints in pin Coupling of Beam Structures

Pin coupling is widely used in engineering structures and its local strength analysis is an important item during design. The methods to calculate joints in pin coupling of beam structures are presented and analysis, then the finite element modeling and the whole calculating process of beam structures with pin coupling are discussed. The concentrated forces under pin roll are transformed into equivalent pressure and the expressions of the equivalent linear and cosine pressure function are derived. The example’s results show that the finite element solutions of the two equivalent pressure functions are similar and these equivalent pressure functions can be used for engineering calculation of joints in pin coupling of beam structures.
Carotid body tumor excisions: adverse outcomes of adding carotid endarterectomy.

Abstract Background Carotid body tumors (CBT) are rare, infrequently malignant vascular neoplasms that are near the carotid bifurcation. Surgical excision is the treatment of choice, but individual surgeons or an institution cannot accumulate sufficient expertise to evaluate their outcomes with confidence. Our purpose was to report outcomes of surgical procedures for CBT from a nationwide dataset. Study design Data were retrieved from the Nationwide Inpatient Sample from nonfederal hospital discharge abstracts. Data were queried for ICD-9-CM code 39.8, operations on the carotid body and vascular bodies, and code 38.2, carotid endarterectomy. Outcomes analyzed were length of stay, charges, and in-hospital mortality. Results An estmated 4,601 operations were identified, 3,746 for CBT surgical procedures only, and in 855 a carotid endarterectomy was also performed. Overall morbidity was 3.3%. Mortality with CBT alone was 2.0% but was 8.8% if carotid endarterectomy was also performed. CBT surgical procedures are most commonly performed in western states where higher elevations are found. Women constituted 59% of the population; mortality for women was higher than for men (12.4% versus 7.9%). Mortality in urban teaching hospitals was 2.1% and in nonteaching hospitals 4.9%. Conclusions CBT surgical procedures are rare but are performed across a broad age spectrum. Mortality rate is low for patients having CBT alone but rises when CE is added. Women are more commonly affected and fare less well. Addition of CE to CBT surgical procedures and the resulting poor outcomes have not been previously described. Consideration should be given to referral of CBT patients to hospitals where mortality rates are low.
Theory for intersubband absorption in quantum dots

Quantum-dot infrared photodetectors (QDIPs) have been researched intensively because normal incidence absorption of the quantum dot layer is possible, unlike quantum-well infrared photodetectors (QWIPs) which require a grating coupled structure or an off-normal incidence configuration to satisfy the polarization selection rules. In this paper, we present a theoretical model for the band structure of a strained quantum dot, modeled as a quantum disk, and the intersubband absorption. We first present analytical expressions for the polarization-dependent optical dipole moments and then calculate the absorption spectra for various carrier densities and temperatures. The effects of carrier density, temperature, and inhomogeneous broadening will be discussed.
A Personality-Based Latent Class Analysis of Emerging Adult Gamblers

Increases in access to gambling venues have been accompanied by increased gambling behavior among young adults. The present research examined associations among Five Factor Model personality traits, motives for gambling, and gambling behavior and problems using latent class analysis. College students (N = 220) completed online measures of personality and gambling behavior as part of a larger intervention trial. Agreeableness and conscientiousness were negatively associated with indicators of gambling behavior. Low agreeableness and high neuroticism were associated with gambling-specific motives, particularly for less frequently endorsed motives. Personality-based latent class analyses of emerging adult gamblers revealed support for three distinct groups reflecting a resilient personality group, a normative personality group, and a vulnerable personality group, which were further differentiated by gambling behaviors and gambling-specific motives. Associations between personality traits and gambling-specific motives highlight potential heterogeneity among college students who gamble. Together, findings suggest that the correlational and latent class-based analyses, as well as the personality and motivation analyses, present complementary information with respect to the attributes of college student gamblers. Implications and future research directions are discussed.
Galvanomagnetic Effects in Antimony

The galvanomagnetic effects in antimomy have been measured at low magnetic fields in the temperature range 50-300\ifmmode^\circ\else\textdegree\fi{}K. It is shown that the behavior of the resistivity and the Hall coefficients at low temperatures is in qualitative agreement with the model of two overlapping bands as proposed by Windmiller and by Falicov and Lin. However, the initial increase in the Hall coefficient ${\ensuremath{\rho}}_{23,1}$ with temperature indicates the possibility of another hole band with the band edge lying close to the Fermi level.
605 Removing Polyps During Both Insertion and Withdrawal Phases Is Associated With Higher Adenoma Detection Rates At Colonoscopy

Mean age, y 62.5 63.5 NS Male sex (%) 76 (44%) 9 (55%) NS Adequate bowel preparation, (%) 168 (99%) 170 (100) NS Total insertion time, min (SE) 8.42 (0.42) 5.10 (0.24) 0.001 Inspection time on insertion, min (SE) 3.11 (0.04) 0 0.001 Total inspection time, m (SE) 9.63 9.44 NS Total procedure time, min (SE) 24.2 (1.04) 27.4 (1.35) 0.07 Adenoma prevalence, n (%) 89 (52%) 98 (59%) NS Mean adenoma per patient, n (SE) 1.38 (0.16) 1.86 (0.21) NS
An Examination of the Relative Impact of Assigned Goals and Self‐Efficacy on Personal Goals and Performance Over Time

A model of goal-setting processes was developed that depicted the influence of previous performance, assigned goals, and self-efficacy on personal goals and performance. Three levels of assigned goals were manipulated in a counterbalanced fashion across two performance trials. Assigned goals were hypothesized to have a greater influence than self-efficacy on personal goals for the first trial, whereas efficacy was hypothesized to have a stronger influence than assigned goals on Trial 2 goals. Although the hypothesized model fit fairly well overall, the specific results concerning the relative impact of assigned goal and self-efficacy were not supported. In general, the observed trends indicated the effects were the opposite of what was expected. Potential explanations for these results and recommendations for future research are offered.
Full-wave reflection of lightning long-wave radio pulses from the ionospheric D region: Numerical model

[1] A model is developed for calculating ionospheric reflection of electromagnetic pulses emitted by lightning, with most energy in the long-wave spectral region (f ∼ 3–100 kHz). The building block of the calculation is a differential equation full-wave solution of Maxwell's equations for the complex reflection of individual plane waves incident from below, by the anisotropic, dissipative, diffuse dielectric profile of the lower ionosphere. This full-wave solution is then put into a summation over plane waves in an angular direct Fourier transform to obtain the reflection properties of curved wavefronts. This step models also the diffraction effects of long-wave ionospheric reflections observed at short or medium range (∼200–500 km). The calculation can be done with any arbitrary but smooth dielectric profile versus altitude. For an initial test, this article uses the classic D region exponential profiles of electron density and collision rate given by Volland. With even these simple profiles, our model of full-wave reflection of curved wavefronts captures some of the basic attributes of observed reflected waveforms recorded with the Los Alamos Sferic Array. A follow-on article will present a detailed comparison with data in order to retrieve ionospheric parameters.
Tritium and proton nuclear magnetic resonance study of the isotope effects on the molecular structure and the degree of order of partially oriented [3H1] benzene

Abstract Tritium and proton nuclear magnetic resonance spectra of [3 H1] benzene partially oriented in a liquid crystal were studied. Isotope effects on the difference in the CH and C 3 H bond lengths and on the degree of order were deduced. The direction of the isotope effect on the ordering is consistent with the theory which attributes ordering to molecular shape and polarizabilities.
A Quantitative Comparison of Blocking Agents in the In Vitro Motility Assay

Blocking agents are used to prevent non-specific binding and stabilize motor proteins, both in prospective nano-scale devices and in vitro assays of motor function. Sacrificial proteins such as bovine serum albumin and casein are typically used. However, these may introduce unwanted nonspecific interactions, and may also not be appropriate for all experimental or device applications. We therefore compared actomyosin function in the motility assay when blocked with proteins and synthetic polymers. Polyvinylpyrrolidone (PVP) preserved higher actin filament velocities and motile fractions than traditional protein blocking agents, while polymers based on polyethylene glycol had a deleterious effect. PVP also supports motility by other motor systems. The data suggest a model in which differential preservation of actomyosin function by blocking agents results from myosin adsorbing to surfaces in different orientations.
The protocadherin PAPC establishes segmental boundaries during somitogenesis in Xenopus embryos

Abstract Background: One prominent example of segmentation in vertebrate embryos is the subdivision of the paraxial mesoderm into repeating, metameric structures called somites. During this process, cells in the presomitic mesoderm (PSM) are first patterned into segments leading secondarily to differences required for somite morphogenesis such as the formation of segmental boundaries. Recent studies have shown that a segmental pattern is generated in the PSM of Xenopus embryos by genes encoding a Mesp-like bHLH protein called Thylacine1 and components of the Notch signaling pathway. These genes establish a repeating pattern of gene expression that subdivides cells in the PSM into anterior and posterior half segments, but how this pattern of gene expression leads to segmental boundaries is unknown. Recently, a member of the protocadherin family of cell adhesion molecules, called PAPC, has been shown to be expressed in the PSM of Xenopus embryos in a half segment pattern, suggesting that it could play a role in restricting cell mixing at the anterior segmental boundary. Results: Here, we examine the expression and function of PAPC during segmentation of the paraxial mesoderm in Xenopus embryos. We show that Thylacine1 and the Notch pathway establish segment identity one segment prior to the segmental expression of PAPC . Altering segmental identity in embryos by perturbing the activity of Thylacine1 and the Notch pathway, or by treatment with a protein synthesis inhibitor, cycloheximide, leads to the predicted changes in the segmental expression of PAPC . By disrupting PAPC function in embryos using a putative dominant-negative or an activated form of PAPC, we show that segmental PAPC activity is required for proper somite formation as well as for maintaining segmental gene expression within the PSM. Conclusions: Segmental expression of PAPC is established in the PSM as a downstream consequence of segmental patterning by Thylacine1 and the Notch pathway. We propose that PAPC is part of the mechanism that establishes the segmental boundaries between posterior and anterior cells in adjacent segments.
Analyte species and concentration identification using differentially functionalized microcantilever arrays and artificial neural networks

In the present work, we have performed analyte species and concentration identification using an array of ten differentially functionalized microcantilevers coupled with a back-propagation artificial neural network pattern recognition algorithm. The array consists of ten nanostructured silicon microcantilevers functionalized by polymeric and gas chromatography phases and macrocyclic receptors as spatially dense, differentially responding sensing layers for identification and quantitation of individual analyte(s) and their binary mixtures. The array response (i.e. cantilever bending) to analyte vapor was measured by an optical readout scheme and the responses were recorded for a selection of individual analytes as well as several binary mixtures. An artificial neural network (ANN) was designed and trained to recognize not only the individual analytes and binary mixtures, but also to determine the concentration of individual components in a mixture. To the best of our knowledge, ANNs have not been applied to microcantilever array responses previously to determine concentrations of individual analytes. The trained ANN correctly identified the eleven test analyte(s) as individual components, most with probabilities greater than 97%, whereas it did not misidentify an unknown (untrained) analyte. Demonstrated unique aspects of this work include an ability to measure binary mixtures and provide both qualitative (identification) and quantitative (concentration) information with array-ANN-based sensor methodologies.
Determination of cystic duct patency using hepatobiliary MRI with gadoxetate disodium: is T1 precontrast imaging necessary

Purpose: To determine the need for precontrast T1-weighted imaging in determining cystic duct patency using hepatobiliary phase imaging with gadoxetate disodium-enhanced magnetic resonance imaging (MRI). Materials and Methods: MRI exams using gadoxetate disodium from October 4, 2008 to April 14, 2010 were reviewed in a retrospective fashion. Two reviewers independently reviewed only the 20-minute T1-weighted delayed postcontrast images to determine the presence of excreted contrast in the gallbladder lumen. Contrast was deemed present if hyperintense signal material was seen in the antidependent portion of the gallbladder lumen. The actual presence of contrast in the gallbladder was determined by directly comparing the pre- and postcontrast T1-weighted images using consensus review. Results: In all, 187 cases were included. Three (1.6%) were deemed indeterminate due to complete homogeneous opacification of the gallbladder. All three cases were identified as indeterminate by both reviewers. Of the remaining 184 cases, 136 filled (74%) and 48 did not fill (26%). Both reviewers correctly identified 136/136 cases of gallbladder filling. Reviewer A identified 47/48 cases of nonfilling and reviewer B identified 46/48 cases of nonfilling. Sensitivity and specificity were 100% and 98% for reviewer A and 100% and 96% for reviewer B, respectively. Conclusion: The presence of excreted contrast in the gallbladder lumen can be determined using gadoxetate disodium-enhanced MRI without precontrast T1-weighted imaging. J. Magn. Reson. Imaging 2011;35:601-606. © 2011 Wiley Periodicals, Inc.
Extended Follow-Up and Outcomes of Patients Undergoing Pancreaticoduodenectomy for Nonmalignant Disease

Due to improved surgical outcomes and increased detection of pancreatic lesions, the resection of nonmalignant and indeterminate lesions of the pancreas has increased. This study aims to assess the outcomes over an extended period of time and the clinical consequences of pancreaticoduodenectomy (PD) performed for nonmalignant indications. Patients undergoing a PD between 2006 and 2010 were retrospectively identified and asked to complete a symptom survey. Charts were reviewed for hospital admissions, emergency room visits, complications, and procedures performed. A total of 132 patients were identified through database review with a median follow-up of 2.8 years. Forty-two patients (31.1%) completed the phone survey. Pain and diarrhea were the most common symptoms reported, negatively impacting the patient’s daily life in 4.9% and 7.3% of patients, respectively. Diabetes developed or worsened in 19.5%, with new insulin required in 12.2%. Complications were rare, with abdominal abscess (7.6%) occurring most commonly. Although some patients experienced symptoms that negatively impacted their daily life or had diabetic issues following surgery, the outcome of patients undergoing PD for nonmalignant indications was generally favorable. Further prospective study is warranted.
Counting correlations in boson beams

Abstract The photon counting correlation phenomena first observed by Hanbury Brown and Twiss are analyzed using methods from the theories of stochastic processes and quantized fields. It is demonstrated that a quantized field which is excited by a c -number source exhibits counting correlations of the Hanbury Brown and Twiss type when the c -number part of the field is a sample function of a stationary random process with statistically independent modes, an example of which is shown to be the blackbody radiation field. The counting covariance for such fields is found to be the sum of two terms: a “quantum mechanical” term which is a consequence of the lack of commutability of the field operators and a term which can be derived from classical theory. This result is shown to be consistent with the existing counting correlation experiments. A discussion of the counting correlation effect from the viewpoint of quantum statistical mechanics is given to demonstrate that the “bunching of bosons” explanation of the effect is, in general, incorrect. Counting correlations in more general types of fields are considered.
The seismic future of cities

The final projected doubling in Earth’s population in the next half century, requires an additional 1 billion housing units, more dwellings constructed in a single generation than at any time in Earth’s history. Earth’s tenfold increase in population has occurred during a time that is short compared to the return time of damaging earthquakes. In the next century, therefore, earthquakes that had little impact on villages and towns, will be shaking urban agglomerations housing upwards of 12 million people. An epicentral hit on a megacity has the potential to cause 1 million fatalities. The incorporation of earthquake resistant structures in the current global building boom, despite successes in the developed nations, has been neglected in the developing nations where historically earthquake damage has been high. The reasons for this neglect are attributed to indifference, ignorance and corrupt practices, not due to an absence of engineering competence. Never has a generation of earthquake engineers been faced with such a grave responsibility to exercise their skills, both political and technical, as now. The eye is bewildered by “a city become an heap”. Robert Mallet (1862).
Manufacturing process design and optimization

Manufacturing process design: process principles process paths optimizing process design. Basic improvement techniqes: problem identification basic problem solving SPC review complex process control. Design of experiments: inputs and outputs control factors experimental arrays control factor interactions orthogonal arrays full factorial arrays fractional factorial arrays response analysis minimizing variation. Appendix: experimental arrays and response tables.
Long-term survival in patients with malignant peritoneal mesothelioma treated with irradiation.

Twelve cases of peritoneal mesothelioma seen at Memorial Hospital, since 1952, are reviewed. Of four patients treated by total abdominal irradiation plus intraperitoneal injection of 32P, two survived more than 10 years and another is alive and well 2 years after treatment. The last patient benefited by more than 1 1/2 years of palliation. All other patients died within 2 years after treatment. It is recommended that all patients with malignant peritoneal mesothelioma be treated by total abdominal irradiation and intraperitoneal instillation of colloidal 32P.
Erythropoietin and organ protection: lessons from negative clinical trials

Based on its pleiotropic effects, erythropoietin can decrease inflammation, oxidative stress, and apoptosis. Erythropoietin provides organ protection for the heart, brain, and kidney in diverse preclinical animal studies, especially models that include ischemia-reperfusion injury and/or inflammation. However, large clinical studies in coronary reperfusion, heart failure, stroke, acute kidney injury, and chronic renal disease have failed to demonstrate improved outcomes. A study in a previous issue of Critical Care examining the ability of erythropoietin to prevent or ameliorate acute kidney injury in patients undergoing complex valvular heart surgery is similarly negative. The failure of erythropoietin in clinical studies may be due to an inadequate dose, since the receptors responsible for organ protection may require higher concentrations than those responsible for erythropoiesis. However, as has occurred in studies in sepsis and acute respiratory distress syndrome, the negative studies probably reflect an inadequate understanding of the complexity of the underlying processes with multiple redundant and interacting pathways that may differ among the large number of different cell types involved. As tools to understand this complexity and integrate it on an organismal basis continue to evolve, we will develop the ability to use erythropoietin and related nonhematopoietic agents for organ protection.
Post-Transcriptional Regulation of Early T Cell Development by T Cell Receptor Signals

During differentiation in the thymus, immature T cells progress through an ordered sequence of developmental stages that are best characterized by variable expression of the co-receptor molecules CD4 and CD8. Crosslinking of T cell receptor (TCR) molecules on precursor thymocytes was found to block their differentiation into CD4+CD8+ cells by eliminating messenger RNA's encoding two families of developmentally important molecules: the co-receptor molecules CD4 and CD8 and the recombination activating genes 1 and 2. TCR-induced post-transcriptional regulation in early thymocytes was specific for selective messenger RNA's, required protein synthesis, and was itself developmentally regulated. These data identify a post-transcriptional mechanism that is influenced by TCR signals and that regulates early thymocyte development.
A study of the VUV emission from highly ionized krypton in a theta pinch plasma

Abstract The ionization rates of Kr(IX), (X), (XI), and (XII) have been measured using a fast 60-kV-60kJ theta pinch as a plasma source. The line emission from each ion stage has been identified and the time evolution observed. A coupled set of rate equations was used along with time- and space-resolved measurements of the electron density and temperature to model the plasma light emission. The ionization rates of Kunze were adjusted by multiplying the rate for each ion stage with a constant until the peak intensity of the calculated emission agreed with the time of the observed peak intensity. The constants required for best fit were 2.5, 0.15, 3.0, and 2.0 for Kr(IX), (X), (XI), and (XII), respectively. Two successive ionization stages, Kr(X) and Kr(XI), have shown the same time dependence and possible reasons for this observation are discussed. During the course of modeling the light emission, we have also found that the rate for the excitation from the 3 d n to the 3 p 5 3 d n +1 level in Kr(X) ( n =9) and Kr(XI) (n=8) is a factor of 5 lower than predicted by the van Regemorter excitation rate equation.
Expression and purification of active recombinant ATM protein from transiently transfected mammalian cells.

Abstract The gene mutated in the human disease ataxia telangiectasia (AT), termed ATM, encodes a large protein kinase involved in DNA repair and cell cycle control. Biochemical characterization of ATM function has been somewhat difficult because of its large size (∼370 kDa) and relatively low level of expression in several systems. The majority of studies have used immunoprecipitated ATM or purified ATM obtained through relatively complex procedures. Here, we describe an efficient method for the expression and purification of FLAG-epitope-tagged recombinant human ATM protein (F-ATM). This method utilizes the expression of F-ATM in transiently transfected 293T cells followed by anti-FLAG-agarose affinity chromatography. The transfection procedure has been optimized for large (225-cm 2 ) culture flasks and F-ATM can be purified to near homogeneity as judged by SDS-PAGE. This procedure yields approximately 1 μg of catalytically active F-ATM protein/225-cm 2 flask that can be used for biochemical studies.
Controller design for performance guarantees in uncertain regulating systems

This paper presents a controller design methodology for a class of uncertain, multivariable, regulating systems required to maintain operating conditions within small tolerances despite a vector step disturbance. Furthermore, each control effort is limited by its hardware, namely the actuator outputs are limited in magnitude and response speed. The design methodology is a frequency domain approach and is based on single loop design. A Gauss elimination technique facilitates the various design steps. The specific class of systems addressed are those which can be modelled as square, multivariable systems with structured (i.e. parametric) and/or unstructured uncertainty. One restriction imposed on the system is that it must be invertible for all plant parameter combinations. The key features of this methodology include (i) the role played by loop interaction in achieving overall system performance; (ii) the ability to accommodate both parametric and unstructured uncertainty; (iii) the explicit consideration ...
On the virtual photon spectrum for electromagnetic dissociation of relattvistic nuclei in peripheral collisions

Abstract We give the virtual photon spectrum appropriate to electromagnetic reactions between relativistic nuclei and stationary massive targets, for all multipoles, in terms of the classical trajectories of the ions. Within the approximation that projectile and target charges do not overlap, the dissociation cross section can be written directly in terms of the various multipole photoabsorption cross sections. The dominant multipole is E1. M1 contributions are shown to be negligible, while E2 effects become significant for heavy projectiles and could be measured in coincidence experiments. The effects of the curvilinear trajectory are also small and can be included with a minor modification of the results for straight-line trajectories.
Beer, beef, and boards: the role of intermediaries in payment for ecosystem services arrangements in northwestern Montana

Payments for ecosystem or ecological services (PES) are voluntary, often market-based approaches to protecting environmental values. In the rural United States, some landowners receive PES through government led conservation programs, but little is known about their involvement in market based arrangements. We analyzed three examples of market based PES arrangements in northwestern Montana: watershed restoration and craft brewing, niche meat production, and certified timber supplies. We find that intermediaries were working between buyers and sellers in each case to set conditions for transactions and undertake the mechanics of implementation. These findings align with existing conceptualizations of intermediaries as crucial links in PES arrangements, but also suggest that intermediaries for market based PES arrangements are not always facilitators or neutral nongovernmental actors; they may actually be from the private sector and drive the process by serving as buyers. This research contributes to strong...
OnH 2 minimization of theH ∞ suboptimal solutions

In this paper we show that theH 2 minimization of theH ∞ suboptimal solutions for a class of suboptimalH ∞ distance problems can be reduced to a finite dimensional nonlinear optimization problem. This extends a result of [7] where the same problem is considered in the Caratheodory-Schur interpolation case.
Using Contrast Material-enhanced Echocardiography to Identify Abnormal Pulmonary Arteriovenous Connections in Patients With Hypoxemia

The phenomenon of abnormal pulmonary arteriovenous connections in patients with acquired lung disease rarely has been reported. We report three patients with acquired lung disease and hypoxia that did not respond to the administration of 100 percent oxygen. Contrast-material-enhanced echocardiography demonstrated intrapulmonary right-to-left shunting in all three patients. These cases suggest that patients with hypoxia due to acquired lung disease may be screened by contrast-enhanced echocardiography to identify the presence and the location of anatomic right-to-left shunts.
Subclinical thyroid dysfunction in the elderly

Subclinical thyroid dysfunction is more common in older persons. By definition, these disorders are recognized by isolated elevation or suppression of the serum TSH concentration, in association with a normal serum free thyroxine level. Among individuals over 65 years old, subclinical hypothyroidism is found in approximately 10% of women and approximately 3% of men. It is most commonly due to autoimmune thyroiditis or previous treatment for hyperthyroidism. There may be three indications for L-thyroxine therapy: (a) presence of antithyroid antibodies, indicating substantial risk of progression to over hypothyroidism; (b) symptoms consistent with thyroid hormone deficiency; and (c) an elevated serum LDL-cholesterol. Subclinical hyperthyroidism is present in approximately 1%-2% of older persons. The most common cause is excessive thyroid hormone therapy, followed by mild endogenous hyperthyroidism due to Graves' disease or nodular goiter. These can be differentiated from other causes of low serum TSH concentration based on clinical and other laboratory and radionuclide scan criteria. The most serious consequences of subclinical hyperthyroidism are atrial fibrillation and osteoporosis, to which elderly patients are particularly predisposed.
Self-similarity in rock physics

Mavko's (1995) “rock physics bottleneck” dictum refers to a common problem in remote sensing: The measured parameters of the object under examination are fewer than the physical properties they depend upon. Yet, even if we have the luxury of reducing the number of inputs to equal the number of measurements, it may not be practically feasible to resolve the resulting mathematically determined system of equations. For example, it may not be possible to determine the porosity and clay content from the P- and S-wave impedance data because both depend on the same linear combination of porosity and clay content. Such situations are described as “self-similar.” A solution to this problem is to procure an additional, depositionally controlled link between the desired outputs, such as a commonly observed relation between the total porosity and clay content.