cssi/SciSciGPT-SciSciNet huggingface dataset:
Calving Bay dynamics and ice sheet retreat up the St. Lawrence Valley system

Ice streams that drain marine ice sheets are particularly susceptible to catastrophic retreat because they flow through bedrock troughs, and grounding line migration would produce a calving bay filled either with an ice shelf or with icebergs. Geological evidence suggests that a calving bay formed in the Laurentian Channel and the St. Lawrence valley after the late-Wisconsin maximum. Retreat rates in this calving bay are calculated for a variety of possible models assuming that locally the late-Wisconsin Laurentide ice sheet extended to the edge of the continental shelf. If an ice shelf forms in front of the retreating grounding line, and the shear stress between the ice shelf and its margins is one bar, retreat continues for only 150 km. Further retreat requires lubrication by ice with a strain-dependent preferred crystal fabric that develops between the ice shelf and its sides, or by complete removal of the ice shelf. Under these conditions the first 300 km of retreat takes at least 3000 to 6000 years. Thereafter, further retreat is rapid until, if a lubricated ice shelf is present, a new equilibrium grounding line is established about 1100 km from the edge of the continental shelf. If massive calving of icebergs occurred at, or near the grounding line, then retreat would continue up the St. Lawrence valley through to Lake Ontario. Of the various models considered, the minimum time taken for retreat from a point 300 km inland from the edge of the continental shelf through to Lake Ontario is about 2000 years.
Lawyer Malpractice and Domestic Violence: Are We Revictimizing Our Clients?

This article explores lawyer malpractice in cases involving domestic violence. The author examines the potential hazards from the perspective of representing the offender as well as the victim. The author advances the idea that domestic violence may be unrecognized in many cases if the attorney is not familiar with the appropriate indicators. In addition, an attorney may be unwilling to raise issues of abuse due to the attorney's own discomfort with the topic. The author argues that the family law lawyer's failure to recognize and address issues of violence places the lawyer at risk for client claims of malpractice as well has other claims.
No Oil for War: The Coercive Power of Energy

Does oil hold special coercive power? Could a country use the threat of oil cutoff to blackmail its enemies? If so, what makes oil especially suited for political coercion? Two perspectives exist on oil coercion: The popular view claims that oil has special coercive power because of its ability to inflict economic punishment on a society. The academic wisdom argues that oil coercion provides little to no leverage because the global nature of the oil market renders embargos ineffective. I argue that oil does hold special coercive leverage because cutoffs can undermine a country’s ability to defend itself. Oil is the indispensible resource for war because military mobility hinges on it. If a state could cutoff oil to its adversary, it could immobilize its forces and defeat it in war. Thus, the threat of military denial, not economic punishment, gives oil its unique coercive potential. But, if oil coercion has so much coercive power, why don’t we see more of it? Coercive success with oil is rare because states are strategic actors cognizant of this danger, and they take anticipatory measures to reduce their vulnerability before an opponent can coerce them. These anticipatory measures may include war. The paper illustrates the coercive power of oil denial through a case study of Japan’s surrender in WWII.
Local Construction of Spanners in the 3-D Space

In this paper we present local distributed algorithms for constructing spanners in wireless sensor networks modeled as unit ball graphs (shortly UBGs ) and quasi-unit ball graphs (shortly quasi-UBGs ), in the 3-dimensional Euclidean space. Our first contribution is a local distributed algorithm that, given a UBG U and a parameter *** $\alpha . The second contribution of this paper is in presenting the first local distributed algorithm for the construction of bounded-degree lightweight spanners of UBGs and quasi-UBGs. The simulation results we obtained show that, empirically, the weight of the spanners, the stretch factor and locality of the algorithms, are much better than the theoretical upper bounds proved in this paper.
The importance of retardation in PEEC models for electrical interconnect and package (EIP) applications

Partial Element Equivalent Circuit (PEEC) models have been employed in both the EMI (Electro-Magnetic Interference) as well as the EIP (Electrical Interconnect and Package) areas. It is generally assumed that the retardation between the circuit elements can be ignored for EIP problems since the radiated fields are not of interest for this application. In this paper, we give some insight into the importance of retardation for EIP problems.
Using visualization tools to teach compiler design

A project-based compiler course presents several challenges to the student-implementor. In addition to the “book learning about” various compiler topics, a student must assimilate a large amount of information about the compiler's implementation. Furthermore he or she must be able understand each source-program construct at a number of different representation levels. Finally, the student must apply that knowledge during implementation and debugging of a compiler. This paper describes a pair of packages that employ Java's graphical capabilities so that a program may be visualized at various stages of the compilation process. We argue that these tools are effective in helping students understand the transformation process from source program to machine code. We summarize our experience in using these tools in the context of a project-based compiler course. We also discuss other features of Java that make it well-suited for a student compiler project.
OUTCOMES FOR ABUSED AND NEGLECTED CHILDREN OF MENTALLY RETARDED PARENTS

Whether mentally retarded parents can care for their offspring is a difficult problem to assess and treat. The Family Assessment Clinic Team has seen over 1000 abused and neglected children over the last 6 years for multidisciplinary assessment and dispositional planning. Seventeen cases in which at least one parent was borderline or mildly mentally retarded were identified for chart review and telephone followup. Findings were: 1. Of 56 children of these families. Probate Court involvement was recommended by the team for 46 (82%), and the court took jurisdiction in all cases when the team recommended it. 2. The average family received 10 community services in addition to public financial support and medical care. 3. In spite of intense professional involvement, only 8 (14%) of the children were able to remain in the care of the retarded parent, usually with extended family support. 4. The court terminated parental rights to 27 (48%) children who were subsequently adopted. 5. Other outcomes were: 4 (7%) were voluntarily given up for adoption; 2 (4%) died (1 by suicide, age 11 yrs; 1 beaten by mother's boyfriend, age 8 mos); 1 (2%) is in the custody of the non-retarded parent following divorce; and the remaining 14 (25%) are in temporary foster care. These findings suggest that when the parent of an abused or neglected child is significantly intellectually limited, the prognosis for greatly improved parenting is poor, even with intensive community services.
Distributing a GIS using a parallel data approach

The limitations of serial processors for managing large computationally intensive dataset problems in fields such as visualization and Geographical Information Systems (GIS) are well known. Parallel processing techniques, where one or many computational tasks are distributed across a number of processing elements, have been proposed as a solution to the problem. We describe a model for visualizing oceanographic data that extends an earlier technique of using data parallel algorithms on a dedicated parallel computer to an object- oriented distributed visualization system that forms a virtual parallel machine on a network computers. This paper presents a visualization model being developed by the University of Southern Mississippi demonstrating interactive visualization of oceanographic data. The test case involves visualization of two and three-dimensional oceanographic data (salinity, sound speed profile, currents, temperature, and depth) with Windows NT Pentium class computers serving as both severs and client workstations.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Harnessing the capabilities of CIM: The critical role of senior management

Abstract This paper first summarizes common approaches to appraising prospective technological innovations and suggests a seemingly more promising approach. The latter is then applied to evaluating computer-aided manufacturing systems. Finally, attention is turned to developing additional means of utilizing the expanding capabilities of computer-integrated management systems.
Ground State of the Helium Atom

BS>Following a recent attempt to analyze the rate of convergence of Rayleigh-Ritz variational calculations on the ground state of helium, the usefulness of inserting fractional powers of the variables into the conventional Hylleraas series was re-investigated. The results have been very successful: With a 164-term trial function containing haif-powers of the variable s = r/sub 1/ + r/sub 2/, we have matched the best eigenvalue obtained by Pekeris, who used 1078 terms of the conventional type. Our extrapolated value for the nonrelativistic eigenvalue is -2,9037243771 a.u., with an estimated uncertainty of about 1/10/sup 10/. (auth)
The addition of norethindrone acetate to leuprolide acetate for ovarian suppression has no adverse effect on ovarian stimulation

Purpose: Our goal was to determine if the addition of norethindrone acetate (NETA) to leuprolide acetate (LA) has an adverse effect on controlled ovarian stimulation (COH) during in vitro fertilization (IVF).
Distinguishing epicardial fat from scar: analysis of electrograms using high-density electroanatomic mapping in a novel porcine infarct model.

Background The presence of epicardial fat can confound the quantification of scar during transpericardial electroanatomic mapping. The electrogram (EGM) characteristics of epicardial fat have not been systematically compared with infarct scar using gross and histopathological analysis as a gold standard. Objective The purpose of this study was to compare the EGM characteristics of epicardial fat with infarct scar. Methods A closed-chest infarction was created in 40–50 kg pigs by occlusion of the circumflex artery for 150 minutes using an angioplasty balloon. This artery was chosen to minimize any potential overlap of epicardial fat with infarct and to spare any septal involvement. After 4–12 weeks of infarct healing, epicardial mapping was performed. EGMs in low-voltage regions ( t -test and χ 2 analysis. Gross and histopathological examination was used to confirm areas of fat and infarct scar. Results Seven porcine hearts were analyzed after high-density epicardial mapping (364 ± 92 points) was performed 48 ± 19 days after infarction. The mean bipolar EGM amplitude was similar in fat and scar (0.77 ± 0.34 vs. 0.75 ± 0.38 mV; P = not significant). The mean EGM duration was longer in scar than in fat (68.8 ± 18.9 vs. 50.1 ± 11.6 ms; P P 4 mm in thickness registered low-voltage bipolar EGMs. Conclusion Scar from healed myocardial infarction exhibits more fractionation and longer EGM duration when compared with fat. Late potentials are highly specific for locating infarct scars.
Varietal chemical differences associated with freezing resistance in forage plants.

Summary The data presented show that many chemical changes occur in the overwintering parts of plants during the development of frost hardiness and that differences exist among species. However, there is still a question as to whether these alterations in plant metabolism are intimately involved in the development of frost hardiness or whether they are merely associated changes. Of the chemical constituents studied in the work reviewed, only the overwinter trends of total free sugars and water-soluble protein nitrogen were consistently correlated with the overwinter trends of frost hardiness.
Relation between Chemical, Mechanical, and Electrical Properties of Nb2O5‐Modified 95 Mol% PbZrO3‐5 Mol% PbTiO3

The use of an Nb2O5-modified PZT (containing approx. =95 mol% zirconate and approx. =5 mol % titanate) in explosively driven electrical power supplies is described. A small but significant number of test specimens exhibit dielectric breakdown during explosive testing. A failure mechanism is proposed in which the electromechanically induced stresses result in fracture. Charged particles released during the fracture process initiate dielectric failure. The fracture toughness and mechanical strength of a given material are about the same for unpoled and poled material, but after pressure depoling, a given material typically exhibits a nominal 50% increase in toughness and strength. Varying the lead concentration from approx. =5 at. % deficiency to approx. =2 at. % excess results in a degradation in toughness and strength. An optimum niobium concentration is observed at approx. =1.8 at. % in terms of mechanical properties and functional performance.
Virtual confocal microscopy

There is a need for persistent-surveillance assets to capture high-resolution, three-dimensional data for use in assisted target recognizing systems. Passive electro-optic imaging systems are presently limited by their ability to provide only 2-D measurements. We describe a methodology and system that uses existing technology to obtain 3-D information from disparate 2-D observations. This data can then be used to locate and classify objects under obscurations and noise. We propose a novel methodology for 3-D object reconstruction through use of established confocal microscopy techniques. A moving airborne sensing platform captures a sequence of geo-referenced, electro-optic images. Confocal processing of this data can synthesize a large virtual lens with an extremely sharp (small) depth of focus, thus yielding a highly discriminating 3-D data collection capability based on 2-D imagery. This allows existing assets to be used to obtain high-quality 3-D data (due to the fine z-resolution). This paper presents a stochastic algorithm for reconstruction of a 3-D target from a sequence of affine projections. We iteratively gather 2-D images over a known path, detect target edges, and aggregate the edges in 3-D space. In the final step, an expectation is computed resulting in an estimate of the target structure.
A New Electrocardiographic Pattern Observed in Cerebrovascular Accidents

An electrocardiographic pattern was encountered in patients with cerebrovascular accidents which consisted primarily of T waves of large amplitude and duration. Large U waves were often present which may fuse in part or entirely within the T wave. Because of the presence and fusion of the T and U waves, the prolonged Q-T interval associated with the pattern was most probably a Q-U interval.
The electrochemical oxidation of 2,6-dichloro-1,4-phenylenediamine

Abstract The electrochemical oxidation of 2,6-dichloro-1,4-phenylenediamine was studied at a glassy carbon electrode in a 50 vol% methanol—water mixture containing 0.1M HClO4. Single sweep voltammograms are compared with curves obtained by digital simulation. Characteristic reaction parameters, such as formal potentials, charge transfer coefficients, rate constants of the electrochemical and the chemical steps, and diffusion coefficients, were determined from potential-step experiments in combination with a simulation—curvefitting routine.
Sensitive giant magnetoresistive-based immunoassay for multiplex mycotoxin detection

Abstract Rapid and multiplexed measurement is vital in the detection of food-borne pathogens. While highly specific and sensitive, traditional immunochemical assays such as enzyme-linked immunosorbent assays (ELISAs) often require expensive read-out equipment (e.g. fluorescent labels) and lack the capability of multiplex detection. By combining the superior specificity of immunoassays with the sensitivity and simplicity of magnetic detection, we have developed a novel multiplex magnetic nanotag-based detection platform for mycotoxins that functions on a sub-picomolar concentration level. Unlike fluorescent labels, magnetic nanotags (MNTs) can be detected with inexpensive giant magnetoresistive (GMR) sensors such as spin-valve sensors. In the system presented here, each spin-valve sensor has an active area of 90 μm × 90 μm, arranged in an 8 × 8 array. Sample is added to the antibody-immobilized sensor array prior to the addition of the biotinylated detection antibody. The sensor response is recorded in real time upon the addition of streptavidin-linked MNTs on the chip. Here we demonstrate the simultaneous detection of multiple mycotoxins (aflatoxins B 1 , zearalenone and HT-2) and show that a detection limit of 50 pg/mL can be achieved.
Pedodiversity in the United States of America

Abstract Little attention has been paid to analyses of pedodiversity. In this study, quantitative aspects of pedodiversity were explored for the USA based on the State Soil Geographic database (STATSGO). First, pedodiversity indices for the conterminous USA were estimated. Second, taxa–area relationships were investigated in each soil taxonomic category. Thirdly, differences in pedodiversity between the USDA-NRCS geographical regions were compared. Fourth, the possible mechanisms underlying the observed relative abundance of soil taxa were explored. Results show that as the taxonomic category decreases from order to series, Shannon's diversity index increases because taxa richness increased dramatically. The relationship between the number of taxa ( S ) and area ( A ) is formulated as S = cA z . The exponent z reflects the taxa-richness of soil ‘communities’ and increases constantly as taxonomic categories decrease from order to series. The “West” USDA-NRCS geographical region has the highest soil taxa richness, followed by the “Northern Plains” region. The “South Central” region has the highest taxa evenness, while taxa evenness in the “West” region is the lowest. The “West” or the “South Central” regions have the highest overall soil diversity in the four highest taxonomic categories, while the “West” or “Northern Plains” regions have the highest diversity in the two lowest taxonomic levels. The high diversity index in the “West” region results from high taxa richness while the high diversity index in the “South Central” region results from an evenness of taxa. As the taxonomic level decreases, the pattern of taxa abundance approaches a lognormal distribution. One of the key findings of this research is that at lower levels of soil taxonomic divisions (especially the series level), soil taxa increase continuously with increasing area, indicating considerable soil endemism in the USA (and likely around the world), a key consideration in conservation and preservation planning.
Stability of critical correlations to nonlinear perturbations

The stability of the critical solutions of Jones's linear differential equation against the addition of a nonlinear term is studied. The class of correlation functions considered include those which do not possess a power-law decay at criticality, but which are of scaling form.
Differential stress induction of individual Alu loci: implications for transcription and retrotransposition.

Abstract While human Alu repeats can be considered to be members of an extremely large, globally regulated, multigene family, each member of this family resides within a different sequence context that might uniquely modulate its transcription. Unique 3′ flanking sequences for several transcriptionally active human Alu elements were identified by cDNA cloning and used for primer extension analysis to compare the basal and stress-induced expression of the corresponding Alu loci. Each of six Alu loci investigated exhibits a unique pattern of expression in three different human cell lines and in response to stress induction. The sequence context surrounding each Alu member uniquely determines its transcriptional regulation. In many cases, the individual Alu loci and total Alu RNA exhibit opposing patterns of expression implying that local rather than global regulation ultimately determines the expression of individual members. Some of the stresses, which induce Alu transcription, increase co-expression of LINE1 RNA, another requirement for Alu retrotransposition.
A novel method for the synthesis of carbon-14-labeled N-[3-(1-methyl-4-piperidinyl)-1H-pyrrolo[3,2-b]pyridin-5-yl]propanamide and its use in quantitative whole-body autoradiography studies

Sumitriptan (1), a non-selective 5-HT1B/1D agonist is an effective therapeutic agent for the acute treatment of migraine, but it is contraindicated for use in patients with known heart disease. The first Selective Serotonin One F Receptor Agonist (SSOFRA), 5-(4′-fluorobenz-amido)-3-(N-methyl-piperidin-4-yl)-1H-indole (2) was demonstrated to be clinically useful in the treatment of migraine. Although 2 exhibited high affinity for the 5-HT1F receptor as well as high selectivity for the 5-HT1F receptor relative to 5-HT1B and 5-HT1D receptors, it demonstrated appreciable affinity for the 5-HT1A receptor. Subsequently, a program was launched to discover SSOFRA's with improved selectivity over other 5-HT1 receptor subtypes. As a result of these efforts, N-[3-(1-methyl-4-piperidinyl)-1H-pyrrolo[3,2-b]pyridin-5-yl]propanamide (3) was found to possess greater than 100-fold selectivity over 5-HT1A, 5-HT1B and 5-HT1D receptors. Pursuant to a potential clinical investigation of 3, its carbon-14-labeled isotopomer has been prepared by a circuitous route from unlabeled 3 and used in quantitative whole-body autoradiography studies in rats. The results of these efforts are reported herein. Copyright © 2005 John Wiley & Sons, Ltd.
Timing Evaluation Tests for Scan Enable Signals with Application to TDF Testing

Scan based transition delay fault (TDF) tests are generally applied in the launch-on-capture (LOC) mode because the scan enable control signal broadcast to all flip-flops on the die is expensive to implement as a fast switching signal needed to support at-speed launch-on-shift (LOS) tests. However, there is mounting evidence that even when applied at much slower speeds, LOS tests often detect a significant fraction of the timing defects, including many unique failures that are missed by LOC test. This suggests the use of combined LOC and LOS test to increase the TDF coverage beyond that attainable by LOC tests alone. However, to maximize the detection of real delay defects, the LOS tests must be applied at the fastest possible speed (up to the functional clock rate) within the timing limitations of the scan enable. To support such testing, in this paper we present the first test technique to reliably evaluate the switching speed of the scan enable signal. This can vary significantly for individually manufactured instances of the same design due to normal process variations at advanced technology nodes, amplified by near quadratic delays in the long interconnect lengths of this broadcast signal. Once the scan enable speed is determined, LOS tests can be applied at the fastest, most effective speed. Furthermore, the availability of this effective low cost LOS test capability also facilitates the partitioning of the scan flip flops through the use of multiple scan enable signals that apply the delay test in mixed LOS and LOC modes in the different partitions. We show that the use of only two scan enable signals in such an approach can significantly increase TDF test coverage, and raise it very close to the highest possible that is achievable only by enhanced scan.
On the mechanism underlying the divergent retinal and bristle defects of M8* (E(spl)D) in Drosophila.

Our results, using endogenous mutants and Gal4-UAS driven transgenes, implicate multisite phosphorylation in repression by E(spl)M8. We propose that these phosphorylations occur in the morphogenetic furrow (MF) to reverse an auto-inhibited state of M8, enabling repression of Atonal during R8 specification. Our studies address the paradoxical behavior of M8*, the truncated protein encoded by E(spl)D. We suggest that differences in N signaling in the bristle versus the eye underlie the antimorphic activity of M8* in N+ (ectopic bristles) and hypermorphic activity in Nspl (reduced eye). Ectopic M8* impairs eye development (in Nspl) only during establishment of the atonal feedback loop (anterior to the MF), but is ineffective after this time point. In contrast, a CK2 phosphomimetic M8 lacking Groucho (Gro) binding, M8SDΔGro, acts antimorphic in N+ and suppresses the eye/R8 and bristle defects of Nspl, as does reduced dosage of E(spl) or CK2. Multisite phosphorylation could serve as a checkpoint to enable a precise onset of repression, and this is bypassed in M8*. Additional implications are discussed.
Multiple-wavelength vertical-cavity surface-emitting laser arrays with a record wavelength span

Multiple-wavelength vertical-cavity surface-emitting laser (VCSEL) arrays are fabricated using a modified patterned-substrate growth technique in a molecular beam epitaxy (MBE) system. We achieved a large lasing wavelength span of 62.7 nm and highly uniform threshold currents with an average of 2.16/spl plusmn/0.81 mA. High repeatibility of wavelength spacing between 15 arrays with sharp wavelength shift rate 117.14 nm/mm is achieved.
Effects of porosity and saturation on shock-wave response in tuffs

Abstract The attenuation of a stress-wave as it propagates through tuffaceous rocks of various porosities and degrees of saturation is investigated by a calculational parameter study. First, the equations of state for the various porous and saturated tuffs considered are constructed from (1) approximations of the loading curves for tuffs at various grain densities, (2) the weight per cent of water under consideration, (3) a loading curve for water, and (4) estimates of loss of gas-filled porosity during loading. Then, these constructed equations of state are used in one-dimensional calculations to examine how peak radial stress and peak particle velocity are affected by porosity and saturation. The investigation was limited to the regions where peak radial stress is below about 40 kbar. The results show that the peak stress at a given distance from the working point decreases over the range from rock at grain density to rock with small amounts of either water or open void space. The first 5 per cent of volume given up to either void or water is most effective in decreasing the stress at a given distance; additional proportions of either void or water produce relatively less effect. Open void is substantially more effective than water-filled space in producing stress-wave attenuation: a few per cent of dry void volume has the same effect on attenuation as several times as much volume of water with no void. When either the gas-filled or total porosity of a material drops below about 5 per cent, peak stress at a given distance is markedly increased. Above about 5 per cent, the peak stress is relatively insensitive to either the gas-filled or the total porosity of a material. The attenuation of peak particle velocities is somewhat similar to stress attenuation through the rock. However, the particle velocity is less sensitive than stress to changes in void fraction or saturation of the rock.
Glass optrode arrays for optogenetic stimulation

Early-generation penetrating waveguide arrays made of glass (SiO2) were micromachined for optogenetic stimulation in able to provide comprehensive and selective access to distributed targets in three dimensions. We characterized light delivery of the device in order to facilitate design optimization and understand its application in tissue. The glass optrodes were formed by dicing, etching, and annealing. A fused silica/quartz substrate was used to produce 10×10 arrays of optrodes with constant geometry having a pyramidal tip at the end of a straight-edge shank; length, width, spacing, tip angle, and even array size can be varied indepedently. Visible light transmission effciency of optrodes was investigated with input from an optical fiber as well as microscope objective lenses. With a 120-µm wide and 1.5-mm long optrode having a tip taper angle of 30o with respect to the optical axis, almost 90% of visible and IR light from a butt-coupled 50-µm multimode fiber is transmitted out of the optrode tips when optrode shanks are surrounded by tissue. In air, the normalized output power decreases according to the area mismatch betweeen optrode shank and the focused beam width from the microscope; visible light transmission is as much as 90% as well.
Urinary striated sphincter: What is its nerve supply?

Abstract Innervation of the voluntary urinary sphincter continues to be a controversial subject. Using retrograde axonal transport techniques to determine the exact nerve supply to the external sphincter has been successful in clarifying this controversy. 1–5 Tracing the transport of horseradish peroxidase (HRP) injected in the voluntary external sphincter and that injected directly in the cut end of the pudendal nerve was done. Transport from both sides ended in the same neurons in the dorsolateral column, thus labelling and identifying the pudendal nucleus which is the mot center for the voluntary urinary sphincter.
The dispersion of pollutants beneath open channels

An experiment and a numerical scheme which combine previously given methods for the dispersion and seepage phenomena have been presented to describe the dispersion of a pollutant in porous media beneath a triangular channel. The combined effect of longitudinal and lateral dispersion was considered. Numerical concentration profiles are given along with a comparison of experimental and numerical data. The technique suggested herein can be extended to other channel shapes and flow fields accounting for the capillary fringe.
Investigation of energy savings in optical networks using bundle link rightsizing methods

We propose several distributed local optimized algorithms to rightsize the capacity of bundle links to achieve energy savings by shutting down corresponding layer-3 router ports and in layer-1 optical components.
Interaction of three and four rarefaction waves of the pressure-gradient system

Abstract We study the two-dimensional pressure-gradient system, a subsystem of the two-dimensional compressible Euler system. We consider the problem of interaction of four rarefaction waves which is one case of two-dimensional Riemann problems. It is known that, when two planar waves interact, there exists a smooth solution in the interaction region. In this paper, we establish the existence of a smooth solution in the hyperbolic domain of determinacy, in which we encounter the interaction of simple and planar waves and shock prevention in simple waves.
Shock-shock interaction on a slender supersonic cone

The transient pressure field produced behind a plane shock wave of arbitrary strength, which encounters a slender supersonic cone head on, is theoretically predicted. The analysis is restricted to small cone angles (in order that Mach-reflexion will occur at the surface) and to inviscid flow.A conical-flow technique is utilized to transform the small-perturbation equations of time-dependent rotational motion of the fluid behind the deflected plane shock into time-independent equations. From these equations, a boundary-value problem for pressure alone, in the Mach-reflexion region, is derived which is solved numerically. Results for the small perturbation pressure field of the cone are contrasted with Smyrl's (1963) results, which hold for a moving wedge, for a range of values of cone and plane shock speeds.
Stress-shielding compared with load-sharing anterior cervical plate fixation: a clinical and radiographic prospective analysis of 50 patients.

Object In a prospective analysis the authors evaluated the clinical and radiographic outcome of 50 consecutive patients who underwent anterior cervical discectomy and fusion and fixation in which either a stress-shielding or a load-sharing plate (Orion and Premier, respectively) was placed. Data obtained in the two cohorts were analyzed to determine whether clinical or radiographic differences would emerge. Methods All patients underwent either one- or two-level fusion in which freeze-dried allogenic tricortical iliac crest bone graft was used. In the first cohort of 25 patients entered into the study, fixation was achieved using a stress-shielding anterior cervical plate (ACP) system, whereas in the second cohort of 25 patients a load-sharing plate system was employed. Patients were evaluated during a follow-up period that ranged from 12 to 35 months. Outcome was determined using a standard questionnaire by which the authors gauged the level of pain, disability, and satisfaction following surgery. The su...
Effect of nutrient compositions in peat hydrolysate on protein and biomass yields of Candida tropicalis

Research was conducted to study the effect of nutrient compositions, at different levels, added in peat hydrolysates on biomass yields and protein of Candida tropicalis. Samples of Minnesota sphagnum peat were hydrolyzed by boiling at 100°C with 1-1 H2SO4 solutions to produce peat hydrolysates which can support the growth of yeast. Peat hydrolysates were adjusted to pH 5.5 and mixed with mineral nutrients (NH4NO3, NaH2PO4 + Na2HPO4, KCl, and MgSO4) and glucose. Among the single nutrients tested, glucose produced the most significant enhancement of biomass yields, followed by NH4NO3, NaH2PO4 + Na2HPO4, KCl, and MgSO4. NH4NO3 was found to be the most important single nutrient affecting protein accumulation in yeast cells, followed by glucose > NaH2PO4 + Na2HPO4 > KCl > MgSO4. However, protein and biomass production was significantly (P ≤ 0.05) greater for combined nutrients than for any single-nutrient enrichment. The level of residual reducing sugars in peat hydrolysate was inversely proportional to cell counts and optical densities. Addition of high concentrations of nutrients delayed the time of reaching to stationary phase in optical density, cell counts, and pH of yeast cultures. In general, as nutrients were increased, significant (P ≤ 0.05) increases in productivity and cell density were observed. However, specific growth rate decreased with increasing nutrient concentrations. It was concluded that nutrient amendments containing supplementary sources of C/N/P/K/S = 400:36:3.3:3.8:1 are most suitable for biomass production and the biosynthesis of protein by C. tropicalis.
Advances in Plankton Imaging Using Digital Holography

An in situ plankton imaging system using a high space-bandwidth product camera and fiber coupled diode laser for digital holography was developed. High quality imaging results and solutions for associated computational challenges are discussed.
Depth from focus using pyramid architecture

Abstract A method is presented for depth recovery through the analysis of scene sharpness across changing focus position. Modeling a defocused image as the application of a low pass filter on a properly focused image of the same scene, we can compare the high spatial frequency content of regions in each image and determine the correct focus position. Recovering depth in this manner is inherently a local operation, and can be done efficiently using a pipelined image processor. Laplacian and Gaussian pyramids are used to calculate sharpness maps which are collected and compared to find the focus position that maximizes high spatial frequencies for each region.
C4-alkoxy-HPD: a potent class of synthetic modulators surpassing nature in AI-2 quorum sensing.

Bacteria have developed cell-to-cell communication mechanisms, termed quorum sensing (QS), that regulate bacterial gene expression in a cell population-dependent manner. Autoinducer-2 (AI-2), a class of QS signaling molecules derived from (4S)-4,5-dihydroxy-2,3-pentanedione (DPD), has been identified in both Gram-negative and Gram-positive bacteria. Despite considerable interest in the AI-2 QS system, the biomolecular communication used by distinct bacterial species still remains shrouded. Herein, we report the synthesis and evaluation of a new class of DPD analogues, C4-alkoxy-5-hydroxy-2,3-pentanediones, termed C4-alkoxy-HPDs. Remarkably, two of the analogues were more potent QS agonists than the natural ligand, DPD, in Vibrio harveyi. The findings presented extend insights into ligand–receptor recognition/signaling in the AI-2 mediated QS system.
Carbon nanotube-based color IR detectors

Carbon nanotube (CNT) has been found to be one of the promising materials for efficient detection and used in different nanoelectronic devices due to its unique electrical properties. Recently, the applications of nanostructural material to infrared (IR) sensors are considered. Our group developed a color detector using a single CNT and demonstrated the good sensitivity of CNT to the infrared light in different ranges. In this report, the CNT bandgap engineering was discussed. The design, fabrication and experimental result of the CNT based color detector were described. The results indicated the heterogeneous electrode structure increased the signal-to-dark current ratio. Moreover, the CNT based color detectors were capable to sense near-infrared signal and middle-infrared signal in room temperature environment.
Delta-n control in GRIN glass by additives in AgCl diffusion baths.

The uptake of silver from a molten silver chloride bath by an aluminosilicate glass is highly sensitive to the presence of sodium in the salt bath under both equilibrium and nonequilibrium conditions. The delta-n resulting from the silver dopant is reduced by nearly an order of magnitude by the addition of just 5-mol % sodium chloride to the melt. The addition of zinc chloride or lead chloride can be used to maintain high delta-n values in the presence of sodium in the melt.
Dave Robbins' art of guessing

Abstract I will try to guess how Dave Robbins guesses such beautiful mathematical results.
Benefits of citrate over EDTA for extracting phenolic acids from soils and plant debris

The effectiveness of various citrate extractions to recover ferulic acid, a phenolic acid, from Cecil Ap and Bt soil and plant surface debris (crimson clover, rye, subterranean clover, and wheat) was compared with that of EDTA extractions. Citrate extractions were equivalent to or better than EDTA in recovering phenolic acids from soil and plant debris. Citrate, unlike EDTA, did not interfere with the Folin & Ciocalteu's phenol reagent when determining total phenolic acid content in soil and plant debris extracts. Care, however, must be taken when using Folin & Ciocalteu's phenol reagent to estimate total phenolic acid content, particularly in the presence of soil organic matter. Citrate was also more effective in extracting phenolic acids from A-horizon soils. Thus, citrate extractions overcome some of the major limitations observed for EDTA extractions.
Figural goodness and the predictability of figural elements

All 126 patterns composed of five dots distributed over the cells of a 3 by 3 matrix were examined for the predictability of their elements. The predictability of a given dot in a given pattern was measured as the percentage of Ss who indicated that dot as one “implied or suggested” by the subpattern composed of the remaining four dots of the pattern. The dots comprising a figurally good five-dot pattern were generally more predictable, one from the others, than the dots comprising a poor pattern. This finding accords with the Gestaltist conception of a good figure as one whose elements are well organized, and it is the state of affairs required by Garner’s hypothesis that better figures are perceived to have fewer alternatives than poorer figures. A mechanism mediating the prediction of an element of a pattern from the other elements was suggested.
Pyridoxal phosphate blocks aggregation of molybdate treated glucocorticoid receptors in HeLa S3 cells.

Abstract We have compared the effects of sodium molybdate and pyridoxal phosphate on the sedimentation properties of cytoplasmic glucocorticoid receptors. Whole HeLa S3 cells were incubated with [3H]-Dex-amethasone (Dex)‡ at 0–4°C to produce unactivated cytoplasmic steroid receptors. When these cells are lysed in 10 mM Tris, 1 mM EDTA, 12 mM α-thioglycerol pH 7.4 (buffer A), [3H]-Dex receptor sediment as 7–8S species in sucrose gradients prepared in the same buffer. Sedimentation of receptors on gradients containing buffer A plus 20mM sodium molybdate (buffer B) results in an ~9S species. Treatment of these receptors with pyridoxal phosphate (10 mM) followed by reduction with NaBH4 and sedimentation on sucrose gradients prepared in either buffer A or B results in the production of 3–4S species.Although [3H]-Dex labeled cells lysed in buffer B yield ~9S species when analyzed in gradients prepared in buffer B, centrifugation of these receptors in buffer A yield 7–8S species. Similarly when cells are lysed in buffer A labeled receptors sediment in sucrose gradients prepared in buffer B as ~ 9S species.Receptors prepared in buffer B and treated with pyridoxal phosphate and NaBH4 sediment in buffer B gradients as two discrete ~7S and ~3.5S species. Pyridoxal phosphate and NaBH4 treated receptors prepared in buffer B sediment as disperse 3–6S species when analyzed in buffer A gradients. Based on these observations we conclude that pyridoxal phosphate, NaBH4 reduced receptors are not particularly susceptible to subsequent molybdate action, but molybdate pre-treated receptors can be influenced by pyridoxal phosphate.
Above-threshold mode discrimination in external reflector and phase-shifted DFB lasers

The longitudinal mode discrimination above threshold in both distributed feedback lasers with one external reflector and those with phase-shifted grating structures is studied. By numerically solving a pair of coupled mode equations, it is shown that when these types of lasers have nonsaturable index coupling, they lose their mode discrimination at powers only a few times the saturation power of the medium due to the effects of spatial hole burning. >
Analysis of Cre-loxP interaction by surface plasmon resonance: Influence of spermidine on cooperativity

To study target site selectivity of one important class of DNA-binding proteins, site-specific DNA recombinases, we developed an automated real-time kinetic assay based on surface plasmon resonance (BIACORE) and formulated a curve-fitting model that takes into account cooperative interactions. Monitoring the interaction between the Cre DNA recombinase and its specific target site loxP by BIACORE, we found that Cre associates with loxP tightly and highly cooperatively. We observed that the cooperative moment of the Cre-loxP interaction is strongly dependent on the concentration of spermidine, a small polyamine influencing DNA conformation. Thus, DNA conformation can have a profound impact on substrate recognition and subsequent recombination.
Cytophotometric analysis of hypothalamic RNA fluctuations during the rat estrous cycle.

Numerous investigations have established that the neural sites which trigger preovulatory gonadotropin release and onset of sexual receptivity in the female rat are localized in the medial preoptic (MPOA) and anterior hypothalamic (AHA) areas a. Subsequent to these early experiments which utilized lesion, electrochemical stimulation and deafferentation procedures, attention has been focused upon characterizing unit activity (firing rate) and metabolic changes within these neural areas7,10. Two general characteristics of regulatory neurons within these areas have been demonstrated. First, metabolic and electrical activity of MPOA and AHA neurons appear to increase in accordance with the timing of their proposed functions. Second, estrogens and progestins can depress both firing rate and neuronal metabolic activity within these areas. The inhibitory actions of ovarian steroids upon unit activity have been paradoxical, since the rostral hypothalamus has been linked with positive feedback control of gonadotropin secretions a. Recent investigations have suggested that ovarian steroids may be repressing inhibitory influences upon these regulatory neurons 6. The objective of the present study was to utilize Azure B absorption microspectrophotometry to quantitate RNA concentrations within neuronal cell bodies of the MPOA and AHA at different stages of the estrous cycle. Selection of RNA concentration as an indicator of neuronal activation was based in part on biochemical studies demonstrating a close relationship between brain RNA levels and neuron activity is. In addition, recent work has shown that changes in RNA concentration associated with endocrine alterations can be quantitated in individual neurons using analytical cytophotometry of Azure B RNA stained brain sections 1. Twenty-seven female Holtzman albino rats were used in this study. All rats were maintained under a 12:12 h light-dark regimen, exhibited at least 4 normal cycles before use, and were sacrificed by ether anesthesia between 9:00 and 11:00 a.m. following determination of the estrous stage. Hypothalamic regions were rapidly
Nkx2.2 regulates cell fate choice in the enteroendocrine cell lineages of the intestine

Nkx2.2 is a homeodomain-containing transcription factor essential for pancreatic islet cell specification. In this study we investigate the role of Nkx2.2 within the small intestine. We have determined that Nkx2.2 is expressed at the onset of intestinal epithelial cell differentiation in specific intestinal cell populations, including a subset of enteroendocrine cells. Similar to its role in the pancreatic islet, Nkx2.2 regulates cell fate choices within the intestinal enteroendocrine population; in the Nkx2.2 null mice, several hormone-producing enteroendocrine cell populations are absent or reduced and the ghrelin-producing cell population is upregulated. The remaining intestinal cell populations, including the paneth cells, goblet cells, and enterocytes appear to be unaffected by the loss of Nkx2.2. Furthermore, similar to the pancreatic islet, Nkx2.2 appears to function upstream of Pax6 in regulating intestinal cell fates; Pax6 mRNA and protein expression is decreased in the Nkx2.2 null mice. These studies identify a novel role for Nkx2.2 in intestinal endocrine cell development and reveal the regulatory similarities between cell type specification in the pancreatic islet and in the enteroendocrine population of the intestine.