cssi/SciSciGPT-SciSciNet huggingface dataset:
An experimental survey of additives for improving dehydrogenation properties of magnesium hydride

Abstract The use of a wide range of additives has been known as an important method for improving hydrogen storage properties of MgH 2 . There is a lack of a standard methodology, however, that can be used to select or compare the effectiveness of different additives. A systematic experimental survey was carried out in this study to compare a wide range of additives including transitions metals, transition metal oxides, hydrides, intermetallic compounds, and carbon materials, with respect to their effects on dehydrogenation properties of MgH 2 . MgH 2 with various additives were prepared by using a high-energy-high-pressure planetary ball milling method and characterized by using thermogravimetric analysis (TGA) techniques. The results showed that additives such as Ti and V-based metals, hydride, and certain intermetallic compounds have strong catalytic effects. Additives such as Al, In, Sn, Si showed minor effects on the kinetics of the dehydrogenation of MgH 2 , while exhibiting moderate thermodynamic destabilizing effects. In combination, MgH 2 with both kinetic and thermodynamic additives, such as the MgH 2 –In–TiMn 2 system, exhibited a drastically decreased dehydrogenation temperature.
NONOBSTRUCTIVE DILATATION OF UPPER URINARY TRACT MAY LATER CONVERT TO OBSTRUCTION

We report on 5 babies found to have pyelocaliectasis or hydroureteronephrosis antenatally who were evaluated soon after birth because of persistent mild or moderate upper urinary tract dilatation. In each instance, vesicoureteral reflux was absent and the technetium-99m diethylenetriaminepentaacetic acid renal scan revealed good function in the ipsilateral kidney. Renogram curves, after furosemide, did not show an obstructed pattern. Indeed, allowing for the dilatation, the drainage patterns were thought to be normal. In each instance the patient represented or was found on follow-up to have increased dilatation. Renograms were then repeated, using the same radiopharmaceutical and dose of diuretic. An obstructive pattern was seen in each instance. These significant observations demonstrate that nonobstructive hydronephrosis, diagnosed prenatally, may later convert to obstruction at the ureteropelvic junction (UPJ) or in the juxtavesical ureter (UVJ). Thus, careful follow-up, for a period yet to be determined, is desirable in patients in whom the initial postnatal evaluation does not demonstrate obstruction by current criteria.
Medications from the web: use of online pharmacies by emergency department patients.

Abstract Background Internet access and online pharmacies are a resource for purchasing medications. It is unclear if this venue is being used by emergency department (ED) patients to obtain medications. Objective We sought to determine the frequency of and to characterize online pharmacy use by ED patients. We hypothesized that students and younger patients would be more likely than others to obtain medications via online pharmacies due to their familiarity with the Internet. Methods This prospective, cross-sectional survey occurred in an urban university ED. We enrolled a convenience sample of adult patients. The study was Institutional Review Board approved, and informed consent was obtained. To determine differences between online pharmacy users and non-users, chi-squared or Fisher’s exact tests were used for categorical data, and t -test or Wilcoxon rank sum tests were used for continuous variables. Results There were 1657 patients who completed the survey. The mean age was 39 years, standard deviation 16 years; 947/1657 (57%) reported awareness of online pharmacies; 89/1657 (5.4%) patients used the Internet to order medications. More patients with prescription plans ordered medications from online pharmacies (94.3% vs. 70%; p p p = 0.2) or student status (13.8% vs. 14.9%; p = 0.8) between the two groups. Conclusions Approximately 5% of ED patients used the Internet to obtain medications. Contrary to our hypothesis, younger patients were not more likely to use the Internet for medications. Patients on multiple medications and those with prescription plans used online pharmacies more frequently.
Complex-analyticity of harmonic maps and strong rigidity of compact Kähler manifolds

Abstract A harmonic map f between two compact Kahler manifolds is shown to be either holomorphic or conjugate holomorphic under a suitable negativity condition on the curvature of the image manifold and a condition on the rank of df. As a consequence, a compact Kahler manifold of dimension ≥2 that is of the same homotopy type as a compact Kahler manifold with suitable negative curvature condition or as a compact quotient of an irreducible classical bounded symmetric domain must be either biholomorphic or conjugate biholomorphic to it.
An Ultrafast Study of Phenyl Azide: The Direct Observation of Phenylnitrenium Ion

Ultrafast photolysis (lambda(ex) = 308 nm) of phenyl azide in 100% formic acid produces a broadly absorbing transient within the instrument time resolution (300 fs), which is assigned to an excited state of the azide. The azide excited state fragments within 300 fs to form singlet phenylnitrene. The decay of the nitrene (tau = 12.0 ps) produces a new species with absorption centered at 500 nm, which is assigned to phenylnitrenium ion. The lifetime of phenylnitrenium ion is 110 ps in 100% formic acid. This is the first spectroscopic observation of phenylnitrenium ion.
Six-member stimulus classes generated by conditional-discrimination procedures.

Abstract In conditional-discrimination procedures with three sets of stimuli, A, B, and C, three stimuli per set (A1A2A3, B1B2B3, and C1C2C3), subjects (children and adults) learned to select Set-B and Set-C comparisons conditionally upon Set-A samples (A1B1, A1C1, A2B2, A2C2, A3B3, A3C3). If the conditional-discrimination procedures also generated equivalence relations, three 3-member stimulus classes would be demonstrable, A1B1C1, A2B2C2, and A3B3C3. In addition to these three sets, the present experiments used three other sets of stimuli--D, E, and F. The subjects learned to select Set-E and Set-F comparisons conditionally upon Set-D samples (D1E1, D1F1, D2E2, D2F2, D3E3, D3F3). This established a second group of three 3-member stimulus classes, D1E1F1, D2E2F2, and D3E3F3. In all, two groups of three 3-member classes were established by teaching subjects 12 conditional discriminations. The two groups of 3-member classes were then combined (successfully for 5 of 8 subjects) into a single group of three 6-member classes by teaching the subjects three more conditional relations (E1C1, E2C2, and E3C3). With three other children, enlarging the classes one member at a time also produced 6-member classes. As a consequence of class formation, 60 untrained conditional relations emerged from 15 that had been explicitly taught. Six of the subjects also proved capable of naming the stimuli consistently in accord with their class membership, but two subjects demonstrated class formation even in the absence of consistent naming.
Attenuated total reflection fourier transform infrared spectroscopy to investigate water uptake and phase transitions in atmospherically relevant particles.

In this study, attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy is used to investigate water uptake and phase transitions for atmospherically relevant particles. Changes in the ATR-FT-IR spectra of NaCl, NH4 NO3, (NH4)2SO4, Ca(NO3)2, and SiO2 as a function of relative humidity (RH) are presented and discussed. For these various particles, water can (1) become adsorbed on the particle surface; and/or (2) become absorbed in the particle structure to form a hydrate salt; and/or (3) become absorbed by the particle to form a liquid solution. Spectral features and analyses that distinguish these various processes are discussed. For the salts that do undergo a solid to liquid phase transition (deliquescence), excellent agreement is found between the measurements made here with ATR-FT-IR spectroscopy, a relatively simple, inexpensive, and readily available analytical tool, compared to more expensive, elaborate aerosol flow reactor systems using tandem differential mobility analyzers. In addition, for particles that adsorb water, we show here the utility of coupling ATR-FT-IR measurements with simultaneous quartz crystal microbalance (QCM) measurements. This coupling allows for the quantification of the amount of water associated with the particle as a function of relative humidity (f(RH)) along with the spectroscopic data.
Rod cyclic nucleotide-gated channels have a stoichiometry of three CNGA1 subunits and one CNGB1 subunit.

Abstract Phototransduction relies on the precise balance of speed and sensitivity to achieve optimal performance. The cyclic nucleotide-gated (CNG) ion channels, with their Ca 2+ permeability, high sensitivity to changes in cytosolic cGMP, rapid gating kinetics, and Ca 2+ -calmodulin modulation, are beautifully optimized for their role in light detection. Many of these specializations come about from the heteromeric composition of the native channel, comprised of CNGA1 and CNGB1 subunits. However, the stoichiometry and arrangement of these subunits is unknown. Here we have used an approach based on fluorescence resonance energy transfer (FRET) to determine the composition of the intact functional channel in the surface membrane. We find, surprisingly, that the channel contains three CNGA1 subunits and only one CNGB1 subunit. These results have implications for CNG channel function in particular and assembly of membrane proteins in general.
Alternate solution procedures for the location-routing problem

Abstract The location-routing problem occurs in the context of physical distribution system design. Important elements in the design of a physical distribution system are location of depots and distribution of goods from depots to customers. Most research on the location of depots assumes that the distribution of goods from depots to customers occurs in a straight to-and-back manner while computing distribution costs, which is true only if the delivery to each customer is a truckload. For less than truckload (LTL) deliveries to customers, multiple customers are served in a single route. Thus, the true distribution costs are the route costs for all customers. The location-routing approach, which considers routing costs during the location of depots overcomes this deficiency. In this research, three new location-routing models are developed and compared. Their overall performance is evaluated in comparison to existing location-routing approaches based on location-allocation modeling, followed by routing on the allocated customer set. The results show the superior performance of the new location-routing models.
The history and future of the Office of Research Integrity: Scientific Misconduct and Beyond.

This paper looks at the issues and controversies that led to creation of the Office of Research Integrity (ORI) and that dominated its agenda in the early years. The successes and failures of ORI are described and new problems identified. This paper then looks ahead to the future, considering what issues will dominate ORI’s agenda and affect the research institutions, individual scientists, and the scientific community in the next several years.
Cognitive therapy for anxiety disorders.

Cognitive behavioral interuentions offer short-term methods to cope with anxiety. Focusing on personal perceptions, this approach expands nonmedical treatments for anxiety.
Capacity costs, heterogeneous users, and peak-load pricing

The author responds to Vicery's defense of the conventional peak-load pricing model that allows for ex ante external subsidies when users have non-uniform capacity needs. Continuing the airport analogy, the author explores how the marginal cost of providing service to the first user denied use of the facility because of congestion is greater than that user's potential marginal benefit. The illustrations show that the conventional model fails to allocate resources efficiently. It is only with the broader view of marginal cost that the marginal benefit and cost of the marginal user are equal. Apparent marginal cost is for the case of heterogeneous users of a joint facility.
Solid-state NMR studies of proteins immobilized on inorganic surfaces

Solid state NMR is the primary tool for studying the quantitative, site-specific structure, orientation, and dynamics of biomineralization proteins under biologically relevant conditions. Two calcium phosphate proteins, statherin (43 amino acids) and leucine rich amelogenin protein (LRAP; 59 amino acids), have been studied in depth and have different dynamic properties and 2D- and 3D-structural features. These differences make it difficult to extract design principles used in nature for building materials with properties such as high strength, unusual morphologies, or uncommon phases. Consequently, design principles needed for developing synthetic materials controlled by proteins are not clear. Many biomineralization proteins are much larger than statherin and LRAP, necessitating the study of larger biomineralization proteins. More recent studies of the significantly larger full-length amelogenin (180 residues) represent a significant step forward to ultimately investigate the full diversity of biomineralization proteins. Interactions of amino acids, a silaffin derived peptide, and the model LK peptide with silica are also being studied, along with qualitative studies of the organic matrices interacting with calcium carbonate. Dipolar recoupling techniques have formed the core of the quantitative studies, yet the need for isolated spin pairs makes this approach costly and time intensive. The use of multi-dimensional techniques to study biomineralization proteins is becoming more common, methodology which, despite its challenges with these difficult-to-study proteins, will continue to drive future advancements in this area.
Predicting children's reported eating disturbances at 8 years of age.

ABSTRACT Objective To examine differential parental influences on eating attitudes and behaviors of 8-year-old children with a specific focus on gender effects and to assess the specificity of this relationship. Method One hundred eight infants were monitored from birth and interviewed at age 8 for eating disturbances and negative affect with an adaptation of the McKnight Risk Factor Survey. Parental measures included the Three Factor Eating Questionnaire subscales Disinhibition and Restraint as well as body mass index, assessed at study entry. Results No gender differences were found for frequencies of children's self-reported eating disturbances. Higher maternal restraint scores predicted worries about being too fat in girls but not in boys. Higher maternal disinhibition scores also differentially predicted weight control behaviors in their daughters. Negative affect in the child was (weakly) predicted by higher maternal body mass index. No association between paternal predictors of disturbed eating and the child's eating disturbances and negative emotionality was found. Conclusions The impact of maternal eating disorders and disturbances is much stronger than that of fathers and is specifically directed at their daughters. The clinical importance of these disturbances in terms of precursors of adolescent eating disorders has to be determined by monitoring the sample through puberty.
Self-consistent solutions for vacuum currents around a magnetic flux string

We consider the feedback effects of the vacuum currents induced by a magnetic flux string in 2+1 dimensions. Self-consistent induced charge and current densities that satisfy both the Dirac and Maxwell equations are given for the dimensionless coupling constant $g\ensuremath{\equiv}\frac{{e}^{2}}{m}\ensuremath{\rightarrow}0 \mathrm{and} g\ensuremath{\rightarrow}\ensuremath{\infty}$. These quantities for arbitrary $g$ are inferred from the results of the two limiting cases, and also studied numerically.
Coping in thebarrio: Case studies of Mexican-American families

This paper reports preliminary findings of a study of coping abilities of Mexican-American families. The purpose of the study was to identify variables related to styles of behavior that can be characterized as adaptive. A complex of factors differentiated families who were judged to be dealing effectively with their environment (“copers”) from those who were not (“noncopers”). The factors included the health status of the children, various child-rearing attitudes and practices, and patterns of decision making as they related to a more general ability of parents to conceptualize and organize time.
Morphology of a crater-filling lava lake margin, The Peninsula tuff cone, Tule Lake National Wildlife Refuge, California: implications for formation of peperite textures

Abstract A crater-filling lava lake basalt at The Peninsula tuff cone in northeastern California has features on its base formed by interaction of the basalt with wet hydrovolcanic tuff. A spectrum of features, including elongated, streamlined, flute-shaped lobes, and irregular corrugations, are exposed on the base of the lava lake. Flute-shaped lobes range in amplitude from several centimeters to 0.5 m, plunge downdip with respect to the subjacent layered tuff toward the center of the crater, and are better defined at depths more than 3 m below the lava lake surface. These may have been formed by growth of Rayleigh–Taylor instability waves caused by the density contrast between the wet tuff and basalt, combined with directed stress from flow of the lava lake radially outward from the crater. Formation of an insulating vapor film at the wet tuff–basalt interface and downward pressure exerted by the lava lake allowed the edge of the lava lake to quench gradually, and prevented formation of peperite at greater depths in the lake. Corrugations exposed on the upper 1.5 m of the lava lake margin increase in size from several millimeters to 10 cm in amplitude toward the top of the lava lake and approximately parallel the surface. Corrugations may be the remnant of fluidal peperite preserved on the edge of the lava lake, where the peperite was eroded, or may be deformation features formed within an insulating vapor film due to oscillation of the vapor film. These were formed higher in the lava lake, where the lava lake basalt was thinner, wet tuff deposits confining the lava lake were thinner, and temperature differences between the wet tuff and lava were greater. If corrugations represent deformation of the lava edge within the vapor film, rather than peperite formation, they preserve an intermediate process that is involved in the formation of peperite. This study offers a unique opportunity to evaluate some of the initial mechanisms involved in the formation of peperite based on features preserved in the lava where the host rock, in this case hydrovolcanic tuff, has been eroded but the properties of the host rock are known from adjacent exposures.
A constraint satisfaction network for matching 3D objects

A new approach is presented for matching visible surfaces of 3D objects using a constraint satisfaction network. This in turn provides the necessary basis for volumetric reconstruction from multiple views. By matching, the authors mean both to establish correspondence between individual faces and to compute 3D transform that would bring one in correspondence with the other. Toward this goal, constraints at three different levels of complexities are specified to produce stable and coherent assignments. The constraint satisfaction is implemented as a Hopfield network with an appropriate energy functional and minimized using simulated annealing. The system extracts objects faces by computing their bounding contours with adaptive scale space filtering. This process identifies important surface features such as jumps or occluding boundaries and creases. The pointwise feature descriptors are then linked, and an attributed graph is derived to represent the object. The nodes in the graph represent geometric surface features, and the links in the graph represent the relationship between adjacent surfaces. The authors present results on real images. >
Rational Estimation of Construction Impact on Pavement Performance

The goal in any highway construction project is to produce a durable pavement that will perform satisfactorily throughout its expected design life. The quality of construction also plays a significant role in accurately predicting the life-cycle performance. In that context, the quality of construction is defined as meeting a structural-related target variable with minimal variance. The implementation of effective performance-based construction quality management requires a tool for determining impact of construction quality on the life-cycle performance of pavements. This process should carefully consider that relevant parameters are different for different types of pavements. What is not so obvious is that for the same type of pavement, the relevant parameters change with the relative structure of the pavement. Many parameters that are important for a thick pavement designed for an Interstate highway may be of secondary significance to a secondary road. Simply put, defining one set of parameters that can be used in all projects is not appropriate because it may not be cost-effective. A statistical-based algorithm is presented; it was developed to reconcile the results from several pavement performance models used in the state of practice with systematic process control techniques. These algorithms identify project-specific parameters that should be the focus of the construction quality management by quantifying the variability of the construction parameters. The identification of these parameters allows for transportation agencies to focus their limited funds and resources more efficiently while increasing the life of the pavement.
Field Tests of Alfalfa Selected for Resistance to Potato Leafhopper in the Greenhouse

Seedlings of 10 alfalfa entries selected for resistance or susceptibility to Empoasca fabae (Harris) in the greenhouse and unselected seedlings of the same entries were transplanted in the field and evaluated visually (1-9 ratings) for yellowing on 2 dates. The percentages of resistant plants from the 3 Groups differed little on the 2 dates, indicating that the frequency of field-resistant plants was not increased by selection for resistance in the greenhouse. The entries differed significantly in resistance to yellowing.
Effects of Operating Parameters on Countercurrent Extraction of Hemicellulosic Sugars from Pretreated Softwood

In a previous study using a continuous countercurrent screw extractor for two-stage dilute-acid hydrolysis, which was focused on the effects of liquid-to-insoluble solids (L/IS) ratio, we demonstrated that by using low volumes of wash water soluble sugars can be recovered from first-stage pretreated softwood at high yields and also at high sugar concentrations. In this study, we investigated the effects of important operating parameters other than the L/IS ratio, such as the feed rates of water and pretreated biomass and the extractor inclined angle, on the performance of the extractor using first-stage pretreated softwood. As biomass and water feed rates increased at the same L/IS ratio, the recovery yield of soluble sugars decreased, probably owing to a reduced solids residence time in the extractor, which is related to the solid/liquid contact time. The sugar recovery yield was higher at a higher extractor inclined angle. This may be attributed to the effects of increased back mixing and a longer residence time for solids at a higher extractor angle. Countercurrent extraction was also carried out with other pretreated biomass having smaller particle sizes and poor drainage rates. The countercurrent screw extractor was found to be unsuitable for these fine materials due to the slow liquid drainage rate and filter-clogging problems. In a test for stability of soluble sugars in first-stage softwood hydrolysate, irrespective of the storage temperature and storage form, the sugar concentration slowly decreased with storage time. However, storage in slurry form showed higher sugar stability compared with that in liquor form at the same conditions.
Dimensional control of multi-walled carbon nanotubes in floating-catalyst CVD synthesis

Dimensional control in CVD synthesis of MWNT’s is significant and critical to a number of different applications. This study examines the dimensional effect of a number of synthesis variables on the products of floating-catalyst CVD, including catalyst concentration in the feedstock, nanotube growth time, and deposition substrate selection. Extensive diameter surveys are performed by TEM and compared with results from thermo-gravimetric analyses to Raman spectroscopy, offering a novel dimensional analysis of nanotubes grown by FC-CVD methods. CNT diameters are inversely proportional to the catalyst concentration with weak correlation over the range examined and are directly proportional to growth time. Results are combined with prior art to develop a new theory regarding catalyst particle formation over a range of catalyst concentrations. Carbon deposition occurs in two stages, the first characterized by accelerating deposition and increases in CNT diameter and length, the second by etching of the array and carbon deposition at a constant rate. Deposition substrates interact directly with the catalysts to strongly influence the resulting nanotube diameters, based upon the mobility of the catalysts on the substrate surface.
Off-axis scatter measurement of the Mars reconnaissance Orbiter (MRO) Optical Navigation Camera (ONC)

The Optical Navigation Camera (ONC) is part of NASA's Mars Reconnaissance Orbiter (MRO) scheduled for an August 2005 launch. The design is a 500 mm focal length, F/8.3 Ritchey-Chretien with a refractive field corrector. Prior to flight, the off-axis performance of the ONC was measured at visible wavelengths in the off-axis scatter facility at the Space Dynamics Laboratory (SDL). This unique facility is designed to minimize scatter from the test setup to prevent data corruption. Testing was conducted in a clean room environment, and the results indicate that no detectable contamination of the optics occurred during testing. Measurements were taken in two time frames to correct an unanticipated stray light path, which occurred just outside of the sensor's field-of-view. The source of the offending path was identified as scatter from the edges of the field corrector lenses. Specifically, scatter from the interface between the flat ground glass and polished surfaces resulted in significant "humps" in the off-axis response centered at ± 1.5°. Retesting showed the removal of the humps, and an overall satisfactory performance of the ONC. The troubleshooting, correction, and lessons learned regarding the above stray light path was reported on in an earlier paper. This paper discusses the measurement process, results, and a comparison to a software prediction and other planetary sensors. The measurement validated the final stray light design and complemented the software analysis.
Electrospun nanofiber biosensor for measuring glucose concentration

An amperometric biosensor was fabricated using electospun composite nanofiber membrane which are consisted of among polyaniline- polystylene nanofibers. Polyaniline was reacted with camphorsulfonic acid to produce a salt, which was then dissolved in chloroform containing polystyrene. By electrospinning this polymer solution, nanofibers were formed and collected at the counter electrodes. Glucose oxidase was immobilized onto these nanofiber matt using an electrostatic layer-by-layer adsorption technique. In this method, poly(diallyldimethylammonium chloride) was used as the counter ion source. The electrical property of this composite nanofiber was investigated from these nanofibers as a working electrode, and used to measure the glucose concentration accurately.
Oceanography: a bigger nitrogen fix.

Biologically useful nitrogen is delivered to the upper ocean from the depths by vertical transport processes — or such was the received wisdom. In fact, bacteria that convert atmospheric nitrogen may be just as crucial.
Child Sexual Abuse: Immediate and Long-Term Effects and Intervention

ABSTRACT Objective The primary purpose of this review is to highlight the progress made in the area of child sexual abuse during the recent decade and to identify the gaps in our current knowledge about this syndrome. Method More than 100 articles on child sexual abuse were reviewed, the majority written from 1980 to the present concerning the demographics of child sexual abuse, the psychological effects of child sexual victimization, the psychopathology encountered in adult survivors of child sexual abuse, hypotheses regarding the nature of the trauma, a critique of the research, and approaches to intervention. Results Although a wide variety of psychological sequelae have been documented in sexually abused children referred for evaluation or treatment, there appears to be considerable variability in the severity of the symptoms, and we remain ignorant of sequelae in abused children who never enter the mental health system. However, some of these children may become symptomatic in adult life. Validation of sexual abuse is hampered by the lack of specific behavioral markers. Methodological difficulties in child sexual abuse research include problems with definition, failure to measure severity of the abuse, sampling problems, failure to use standardized or appropriate instruments, problems with validation, and failure to use control groups. Conclusions Despite an increased focus on child sexual abuse in the recent decade, many gaps remain in our knowledge. Prospective longitudinal follow-up studies of sexually abused children and treatment outcome studies are urgently needed.
The effect of ENSO on the intraseasonal variance of surface temperatures in winter

The effect of the El Nino–Southern Oscillation (ENSO) on the probability distribution of daily surface air temperature over the Pacific–North American sector is investigated using the US National Centers for Environmental Prediction (NCEP) Reanalysis data for 1959–1998. The El Nino response is characterized by reduced intraseasonal variance over most of the US, western Canada and the Gulf of Alaska. Conversely, there is an increase of variance during La Nina over the US and the west coast, northward to Alaska. The sign of this response is consistent for most individual El Nino/La Nina years in regions with a strong signal. The response is also robust with respect to differing definitions of ENSO or choice of dataset. Finally, a similar response is evident in station data for an earlier period. The change of variance is associated both with altered skewness, and a change in high and low extremes. Extremes of both signs are reduced during El Nino, and are slightly increased during La Nina. These results are consistent with other studies, suggesting an increased incidence of blocking along the west coast of North America during El Nino, leading to less storm activity and less incursions of warm and cold air over the eastern US. While an understanding of the changed variance is important in itself, it also has implications for changes in exceedence statistics (e.g. heating degree days) and the occurrence of extreme values. Copyright © 2000 Royal Meteorological Society
Argon plasma noise temperature similarity

Noise temperature data from argon plasmas at 1-50 mmHg are given. Similarity is shown to exist when the discharge currents are scaled according to a constant current/radius ratio. The consequences of the new method of scaling are discussed.
Three-dimensional modeling and finite element analysis in treatment planning for orthodontic tooth movement

Introduction The objective of this study was to demonstrate the potential of 3-dimensional modeling and finite element analysis as clinical tools in treatment planning for orthodontic tooth movement. High stresses in bone and miniscrew implants under load can cause fractures and trauma for orthodontic patients, and treatments are typically planned by using clinical experience or simple 2-dimensional radiographs. Methods Anatomically accurate 3-dimensional models reconstructed from cone-beam computed tomography scans were used to simulate the retraction of a single-rooted mandibular canine with a miniscrew placed as skeletal anchorage. Detailed stress distributions in the implant and peri-implant bone were found, in addition to the effect of the orthodontic bracket hook length and the angulation of retraction force on stress response in the periodontal ligament (PDL). Results The numeric results showed that the equivalent von Mises stress on the miniscrew under a 200-cN tangential load reached 42 MPa at the first thread recession, whereas von Mises stress in the peri-implant bone only reached 11 MPa below the neck. High tightening loads of 200 N·mm of torsion and 460 cN of axial compression resulted in much greater bone and implant von Mises stresses than tangential loading, exceeding the yield strengths of the titanium alloy and the cortical bone. Increasing the hook length on the orthodontic bracket effectively reduced the canine PDL stress from 80 kPa with no hook to 22 kPa with a hook 7 mm long. Angulating the force apically downward from 0° to 30° had a less significant effect on the PDL stress profile and initial canine deflection. The results suggest that stresses on miniscrew implants under load are sensitive to changes in diameter. Overtightening a miniscrew after placement might be a more likely cause of fracture failure and bone trauma than application of tangential orthodontic force. The reduction of stress along the PDL as a result of increasing the bracket hook length might account for steadier tooth translation by force application closer to the center of resistance of a single-rooted canine. The relatively minor effect of force angulation on the PDL response suggests that the vertical placement of miniscrews in keratinized or nonkeratinized tissue might not significantly affect orthodontic tooth movement. Conclusions This model can be adapted as a patient-specific clinical orthodontic tool for planning movement of 1 tooth or several teeth.
Optimal filter and mollifier for piecewise smooth spectral data

We discuss the reconstruction of piecewise smooth data from its (pseudo-) spectral information. Spectral projections enjoy superior resolution provided the function is globally smooth, while the presence of jump discontinuities is responsible for spurious O(1) Gibbs' oscillations in the neighborhood of edges and an overall deterioration of the convergence rate to the unacceptable first order. Classical filters and mollifiers are constructed to have compact support in the Fourier (frequency) and physical (time) spaces respectively, and are dilated by the projection order or the width of the smooth region to maintain this compact support in the appropriate region. Here we construct a noncompactly supported filter and mollifier with optimal joint time-frequency localization for a given number of vanishing moments, resulting in a new fundamental dilation relationship that adaptively links the time and frequency domains. Not giving preference to either space allows for a more balanced error decomposition, which when minimized yields an optimal filter and mollifier that retain the robustness of classical filters, yet obtain true exponential accuracy.
Nitric oxide donors modulate ferritin and protect endothelium from oxidative injury

Ferritin protects endothelial cells from the damaging effects of iron-catalyzed oxidative injury. Regulation of ferritin occurs through the formation of an iron-sulfur cluster within a cytoplasmic protein, the iron regulatory protein (IP, P) that controls ferritin mRNA translation. Nitric oxide has been shown to inhibit iron-sulfur proteins and is present at vascular sites of inflammation; therefore, we undertook a study to examine the influence of nitric oxide on changes in endothelial cell ferritin content in response to iron exposure, and the subsequent effects on susceptibility to oxidative injury. Iron-loaded endothelial cells (EC) exposed to nitric oxide donors synthesize markedly less ferritin. Treatment of EC with a nitric oxide donor increases IRP affinity for ferritin mRNA concomitant with a loss of cytoplasmic aconitase activity in iron-laden EC. Iron-treated EC exposed to NO donors were resistant to oxidative injury despite their low ferritin content when examined 1 h after the treatment period. In contrast, 24 h later, these same cells become sensitive to oxidants, whereas iron-treated EC that are ferritin-rich continue to be resistant. In conclusion, NO inhibits the increase of EC ferritin after exposure to iron but provides short-term protection against oxidants; ferritin, in turn, provides durable cytoprotection by inactivating reactive iron.
Queries with difference on probabilistic databases

We study the feasibility of the exact and approximate computation of the probability of relational queries with difference on tuple-independent databases. We show that even the difference between two "safe" conjunctive queries without self-joins is "unsafe" for exact computation. We turn to approximation and design an FPRAS for a large class of relational queries with difference, limited by how difference is nested and by the nature of the subtracted subqueries. We give examples of inapproximable queries outside this class.
Tricuspid valve prolapse diagnosed by cross-sectional echocardiography.

Cross-sectional echocardiography utilizing the apical and longitudinal right ventricular inflow tract views was used to investigate the tricuspid valve in 64 patients with mitral valve prolapse and 16 controls who had no angiographic or echocardiographic evidence of mitral valve prolapse. The tricuspid valve leaflets and their coaptation point in systole were found to be below (towards the right ventricular apex) the level of the tricuspid valve ring in systole in all controls. Tricuspid valve prolapse, defined as the leaflets) of the tricuspid valve lying above the tricuspid valve ring level within the right atrium, was seen in 31/64 (48 percent) of patients with mitral valve prolapse. The right ventricular inflow tract view demonstrated tricuspid valve prolapse most readily compared to the apical view, and 29 of the 31 patients with tricuspid valve prolapse had prolapse of at least two leaflets of the tricuspid valve. The 31 patients with both mitral and tricuspid valve prolapse, when compared to the 33 patients with mitral valve prolapse alone, had more symptomatology and abnormal physical findings.
An indirect method to assay for mitotic centers in sand dollar (Dendraster excentricus) eggs.

It is possible consistently to induce sea urchin and sand dollar eggs to cleave directly from one cell into four cells. This is done by exposing the fertilized eggs to benzimidazole for 20 to 30 min beginning about early metaphase. The mitotic apparatus regresses, the cells do not cleave, and shortly after they are returned to normal sea water an early-prophase-appearing nucleus is present in each cell. Each cell then organizes a tetrapolar tetrahedral mitotic apparatus de novo, instead of transforming a bipolar mitotic apparatus into a tetrapolar figure, and cleaves one-to-four. In another type of experiment, it appears that sand dollar eggs exposed to mercaptoethanol during the first period of mitotic center duplication have only half as many centers by first cleavage metaphase as the normal controls. This is consistent with an earlier report by Mazia et al (1960). Using this same experimental technique, it was demonstrated that benzimidazole, on the contrary, does not interfere with mitotic center duplication in sand dollar eggs. A labeling experiment demonstrated that benzimidazole does not interfere markedly with the normal pattern of incorporation of C14-thymidine into the DNA of sea urchin eggs. The data reported here suggest that judicious treatment of sand dollar eggs (and probably sea urchin eggs, too) with benzimidazole can induce the eggs to cleave into as many cells as there were mitotic centers sometime earlier, for example at early metaphase of the first cleavage division. This provides a very useful tool for studies on the process of mitotic center duplication.
Foundation species loss affects vegetation structure more than ecosystem function in a northeastern USA forest

Loss of foundation tree species rapidly alters ecological processes in forested ecosystems. Tsuga canadensis, an hypothesized foundation species of eastern North American forests, is declining throughout much of its range due to infestation by the nonnative insect Adelges tsugae and by removal through pre-emptive salvage logging. In replicate 0.81-ha plots, T. canadensis was cut and removed, or killed in place by girdling to simulate adelgid damage. Control plots included undisturbed hemlock and mid-successional hardwood stands that represent expected forest composition in 50-100 years. Vegetation richness, understory vegetation cover, soil carbon flux, and nitrogen cycling were measured for two years prior to, and five years following, application of experimental treatments. Litterfall and coarse woody debris (CWD), including snags, stumps, and fallen logs and branches, have been measured since treatments were applied. Overstory basal area was reduced 60%-70% in girdled and logged plots. Mean cover and richness did not change in hardwood or hemlock control plots but increased rapidly in girdled and logged plots. Following logging, litterfall immediately decreased then slowly increased, whereas in girdled plots, there was a short pulse of hemlock litterfall as trees died. CWD volume remained relatively constant throughout but was 3-4× higher in logged plots. Logging and girdling resulted in small, short-term changes in ecosystem dynamics due to rapid regrowth of vegetation but in general, interannual variability exceeded differences among treatments. Soil carbon flux in girdled plots showed the strongest response: 35% lower than controls after three years and slowly increasing thereafter. Ammonium availability increased immediately after logging and two years after girdling, due to increased light and soil temperatures and nutrient pulses from leaf-fall and reduced uptake following tree death. The results from this study illuminate ecological processes underlying patterns observed consistently in region-wide studies of adelgid-infested hemlock stands. Mechanisms of T. canadensis loss determine rates, magnitudes, and trajectories of ecological changes in hemlock forests. Logging causes abrupt, large changes in vegetation structure whereas girdling (and by inference, A. tsugae) causes sustained, smaller changes. Ecosystem processes depend more on vegetation cover per se than on species composition. We conclude that the loss of this late-successional foundation species will have long-lasting impacts on forest structure but subtle impacts on ecosystem function.
A SIR-model with square-root dynamics: An NSFD scheme

We present a SIR-model for which the interaction term is expressed as the square-root of the S and I variables. General results on the behaviour of the solutions are discussed and a discrete-time, finite difference scheme is constructed using the NSFD methodology of Mickens. An important feature of the scheme is that both the positivity and a conservation law for the system of differential equations are maintained by the discretization.
Multiaperture telecentric lens for 3D reconstruction

We present a telecentric lens that is able to gain 3D information. The proposed lens system has multiple aperture stops, which enable it to capture multidirectional parallel light rays, while a conventional telecentric lens has only one aperture stop and can capture only light rays that are perpendicular to the lens. We explain the geometry of the multiaperture telecentric system and show that correspondences fall on a line like those in a conventional stereo. As it is a single-lens sensor, we also introduce the principles of 3D reconstruction. Unlike a conventional stereo camera, the disparity of a scene point measured by the proposed lens system is linearly proportional to the depth of a scene point.
Acetylcholinesterase mobility and stability at the neuromuscular junction of living mice.

Acetylcholinesterase (AChE) is an enzyme that terminates acetylcholine neurotransmitter function at the synaptic cleft of cholinergic synapses. However, the mechanism by which AChE number and density are maintained at the synaptic cleft is poorly understood. In this work, we used fluorescence recovery after photobleaching, photo-unbinding, and quantitative fluorescence imaging to investigate the surface mobility and stability of AChE at the adult innervated neuromuscular junction of living mice. In wild-type synapses, we found that nonsynaptic (perisynaptic and extrasynaptic) AChEs are mobile and gradually recruited into synaptic sites and that most of the trapped AChEs come from the perijunctional pool. Selective labeling of a subset of synaptic AChEs within the synapse by using sequential unbinding and relabeling with different colors of streptavidin followed by time-lapse imaging showed that synaptic AChEs are nearly immobile. At neuromuscular junctions of mice deficient in α-dystrobrevin, a component of the dystrophin glycoprotein complex, we found that the density and distribution of synaptic AChEs are profoundly altered and that the loss rate of AChE significantly increased. These results demonstrate that nonsynaptic AChEs are mobile, whereas synaptic AChEs are more stable, and that α-dystrobrevin is important for controlling the density and stability of AChEs at neuromuscular synapses.
What's New and Useful in Law Analysis Technology?*

Decision-aiding software is probably the most important technological innovation from the perspective of lawyer decision-making, as contrasted to efficient office management. That kind of technological breakthrough can be helpful to lawyers in negotiating settlements favorable to their clients without expensive litigation. The technology makes use of benefit-cost analysis, multi-criteria decision analysis, spreadsheet software, and especially super-optimizing analysis whereby plaintiffs, defendants, and other parties can all come out ahead of their best initial expectations simultaneously. Decision-aiding software can also be helpful to lawyers in evaluating alternative precedents, statutes, regulations, and other legal policies to arrive at versions favorable to their clients without an expensive adoption campaign.
Some Physico-Chemical Properties of Lactose

Summary The crystalline habit of alpha hydrate varies greatly under different condition of crystallization. The relationship between the different types of crystals was traced: first, by examining many crystals varying by imperceptible degrees from one another; and second, by changing conditions during crystallization, thereby causing crystals to develop new faces and to alter their habit of growth. The principal factor governing the crystalline habit of lactose is the precipitation pressure, the ratio of the actual concentration to the solubility. By varying this ratio, a great variety of crystal types may be produced. The influence of sucrose upon the crystalline form of lactose is not a specific action but is due to its precipitating effect upon that sugar. Both alpha hydrate and beta anhydride will form needles if crystallization is sufficiently rapid. The two may be distinguished readily by the fact that the prisms of alpha hydrate are always straight while those of beta anhydride are curved.