cssi/SciSciGPT-SciSciNet huggingface dataset:
Interactive ray tracing with the visibility complex

Abstract We describe a method of producing ray-traced images of 2D environments at interactive rates. The 2D environment consists of a set of disjoint, convex polygons. Our technique is based on the visibility complex [17] , [19] [Pocchiola M, Vegter G. Proc Int J Comput Geom Applic 1996;6(3):279–308. Riviere S. Visibility computations in 2D polygonal scenes. PhD thesis, Univ. Joseph Fourier, Grenoble I, France], a data structure in a dual space where a face of the visibility complex corresponds to a contiguous set of rays in the primary space with the same forward and backward views. Sweeping the viewing ray around a viewpoint corresponds to walking along a trajectory on the visibility complex. Producing a ray-traced image is equivalent to walking along and maintaining a set of trajectories. Generating ray-traced images with the visibility complex is very efficient since it uses the coherence among the rays effectively. We have developed a new algorithm for the randomized incremental construction of the visibility complex. The advantage of using an incremental algorithm is that the history of the incremental construction yields an efficient ray-query data structure, which is required for casting secondary rays. The performance of our algorithm is analyzed and a comparison is made with the classical ray-tracing algorithm.
A Model Expressing the Relationship between Catch and Soak Time for Trap Fisheries

Abstract In trap fisheries, catch per trap haul changes with soak time. Catch rates should therefore be standardized for differences in soak time when used to measure abundance. Several models have been used to describe catch per trap haul while adjusting for soak time. Some of these models are limited with respect to time spent fishing or have difficulties in parameter estimation. In this paper, we describe a model without limitations on soak time. The model is Ct = ab + a(t – b)e–ct ; Ct is the catch per trap haul at soak time t; a, b, and c are parameters to be estimated. When sufficient data are used, the term ab denotes asymptotic catch after an infinite soak time, and a and c depend on local animal density, entry rate, and escape probability. These parameters can be readily estimated by many popular computer programs. This model is equivalent, or superior, to other models and is the only suitable model for long soak times with nonzero catch.
Dermatogeriatrics: a case for developing a new dermatology subspecialty

Rising standard of living and rapid advancement in medicine have led to a population that is living longer and longer. Life expectancy for a male born today in the United States is 75.4 years and f...
What's in It for Me?: The Impact of Congressional Casework on Incumbent Evaluation

Research has shown that members of the United States Congress, especially in the House, exploit the abundance of electorally productive perquisites of office available to them. Yet research has not made clear the actual impact of this exploitation on constituents. In this study, I use actual member-constituent contacts in a congressional district to determine the effect of casework on incumbent evaluation. The results indicate that, although casework does benefit the incumbent, its impact is specified by partisanship. In addition, findings show that casework has a ripple effect on the formation of constituent opinion in the district.
Interfacial pattern formation in the presence of solidification and thermal convection

An analysis is conducted on the coupling between hydrodynamic behaviors and a solid-liquid interface that forms due to solidification of a portion of a layer of fluid located between almost completely insulating plates. Beginning with a long-wavelength expansion, an evolution equation is derived that includes the effects of the field variables in the liquid phase, which describes the temporal and spatial behavior of the interface. An expression is obtained that shows that increases in the thickness of the solid layer increase the critical value of the Rayleigh number and that deformations in the interface can either decrease or increase this critical value. The interface undergoes a transition from the planar state to a given pattern at the critical value of the Rayleigh number. Analysis of the evolution equation leads to the prediction that the interfacial pattern consists of squares at very small values for the thickness of the solid layer. A critical value of the thickness is found, and for a thickness greater than this value squares and rolls are predicted to coexist as stable interfacial patterns.
Synergistic effects of co-dopants on the dehydrogenation kinetics of sodium aluminum hydride

Abstract A systematic analysis of the effect of co-dopants on the dehydrogenation kinetics of freshly doped and ball milled NaAlH 4 samples was carried out with chlorides of Ti, Zr and Fe as the catalysts. Numerous samples of NaAlH 4 when co-doped with binary and ternary combinations of Ti, Zr and Fe at 4 mol% total catalyst content exhibited synergistic behavior, with respect to improving the dehydrogenation kinetics of the first decomposition reaction (i.e., NaAlH 4 → Na 3 AlH 6 ) over that of a sample of NaAlH 4 doped with 4 mol% Ti or Zr as single catalysts. In general, the dehydrogenation kinetics improved with the amount of Ti present in a co-doped sample, whether it was a binary or ternary system, with the top five performers all having at least 2 mol% Ti as one of the co-dopants. The binary combination of 3 mol% Ti–1 mol% Fe exhibited the best synergistic performance, with dehydrogenation rates 3.7, 2.0 and 1.5 times that of 4 mol% Ti alone at 90, 110 and 130 °C, respectively. The binary co-doped Zr–Fe system exhibited more pronounced synergistic effects than did the binary co-doped Ti–Fe system; however, their performance was always worse because Ti is a better single catalyst than Zr. The least synergism was exhibited by the binary co-doped Ti–Zr system, where it was surmised that the superior electron sharing ability of electron rich Fe was responsible for it being a better promoter of Ti and Zr than Zr was of Ti. This supposition was further supported by the systematic trends observed with the ternary co-doped systems, with their synergistic effects seemingly limited to binary combinations of the Ti–Fe and Zr–Fe systems. The effects of Ti, Zr and Fe as co-dopants on the second decomposition reaction (i.e., Na 3 AlH 6 → NaH) were not as pronounced as their effects on the first reaction; but synergisms were still observed, especially with all three binary Zr–Fe co-doped systems and to a lesser extent only with the 3 mol% Ti–1 mol% Fe system. A future study will consider the effects of these co-dopants on the dehydrogenation/rehydrogenation kinetics after cycling.
Fatal acute tumor lysis syndrome, hepatic encephalopathy and flare phenomenon following combined androgen blockade.

Characterized by hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia, increased lactate dehydrogenase (LDH) and metabolic acidosis, the acute tumor lysis syndrome (TLS) results from massive abrupt lysis of cancer cells and is commonly reported following cytotoxic chemotherapy for chemosensitive, particularly hematological, tumors. Acute TLS due to hormonal therapy is extremely rare.1 Tamoxifen or aromatase inhibitor therapy for breast cancer may precipitate TLS, typically heralded by a flare phenomenon.2, 3 However, to our knowledge hormonal therapy for prostate cancer has never been described in association with this syndrome. We report on a patient who suffered from this complication and hepatic encephalopathy after combined androgen blockade (CAB). CASE REPORT
Transformation of Neurospora crassa with the trp-1 gene and the effect of host strain upon the fate of the transforming DNA

Neurospora trp-1+ transformants, obtained by transforming a trp-1 inl strain with plasmid DNA containing the wild type trp1+ gene, were characterized by genetic and Southern blot analyses. The transforming trp-1 gene integrated at or near the resident site in all of the trp-1+ transformants obtained with circular DNA or DNA cut within the trp-1 coding region. The frequency of homologous integration decreased substantially when the donor DNA was cleaved outside the trp-1 coding region. The transformants were very stable mitotically and, in general, also showed meiotic stability. Analysis of trp-1+ transformants obtained with another recipient strain, trp-1+ ga-2 aro-9 inl, showed that homologous integration of donor DNA occurred in only 20% of the transformants, whether circular or linear DNA was used. Thus, the host strain employed for transformation appears to be a major factor in determining the fate of transforming DNA. Southern blot analysis of transformants showed that integration of the transforming DNA at the homologous site occurred by double crossover or gene conversion events rather than by insertion of the entire plasmid DNA. Multiple and apparently non functional integration events were observed in some transformants.
Synthesis of an unspliced cytoplasmic message by an adenovirus 5 deletion mutant

Most genes in eukaryotic cells and their viruses contain non-coding intervening sequences (introns)1–5. These sequences are excised from each transcript during maturation of mRNA by a process known as RNA splicing. Although very little is known about the mechanism by which splicing occurs or its biological significance, several studies have suggested that the removal of introns is a necessary prerequisite to the accumulation of stable, cytoplasmic mRNA6–10. Here we describe a mutant of adenovirus 5 (Ad5) containing a deletion within early region Ela; the deletion prevents splicing of the normal Ela transcripts. The unspliced transcript is found in the cytoplasm of infected cells, showing that for this gene, splicing is not necessary for the biosynthesis of cytoplasmic message.
Continuous Endoscopic Guidance via Interleaved Video Tracking and Image-Video Registration

Endoscopic needle biopsy requires off-line 3D computed-tomography (CT) chest image analysis to plan a biopsy site followed by live endoscopy to perform the biopsy. We present a method for continuous image-based endoscopic guidance that interleaves periodic normalized-mutual-information-based CT-video registration with optical-flow-based endoscopic video motion tracking. The method operates at a near real-time rate and was successfully tested on endoscopic video sequences for phantom and human lung-cancer cases. We also illustrate its use when incorporated into a complete system for image-based planning and guidance of endoscopy.
Adenocarcinoma of the pancreas: detection of occult metastases in regional lymph nodes by a polymerase chain reaction-based assay.

BACKGROUND Stage I (T1-2N0M0) adenocarcinoma of the pancreas is associated with a 5-year survival rate of 15-25%. Despite apparently curative resection and pathologic staging indicating localized disease, these cancers recur. The authors hypothesized that there exists microscopic regional disease that is not detected by surgical exploration or routine histopathology. METHODS Because 90-95% of pancreatic cancers exhibit codon 12 K-ras mutations, the authors examined regional lymph nodes for mutated K-ras as a marker of metastasis. DNA was extracted from paraffin embedded archival specimens (primary tumors and histologically negative lymph nodes) of patients with Stage I pancreatic adenocarcinoma. The target region of K-ras was amplified by polymerase chain reaction (PCR) and tested for codon 12 mutation by BstN1 restriction digestion (restriction fragment length polymorphism [RFLP]) that recognized normal but not mutated sequences. Cell lines that harbored normal or mutated K-ras and resected jejunum or gallbladder were used as controls. The regional lymph nodes of 22 patients whose tumors harbored mutated K-ras were tested. RESULTS Dilution experiments with normal and mutant control cell line DNA demonstrated an assay sensitivity for mutated K-ras of 0.1%. Mutated K-ras was found in at least 1 regional lymph node in 16 (73%) of 22 patients with pathologic Stage I pancreatic adenocarcinoma, which suggested metastases not detected by routine histopathology. DNA sequence analysis was performed in four patients and confirmed identical point mutations in the primary tumor and accompanying PCR/RFLP positive lymph nodes. CONCLUSIONS Pathologic examination of regional lymph nodes in pancreatic adenocarcinoma specimens fails to detect metastases in many patients. Lymph node micrometastasis is one reason for the poor survival rates observed among patients with Stage I cancers. PCR/RFLP may have a role in staging early pancreatic cancers. Cancer 1998;83:1328-1334. © 1998 American Cancer Society.
Criterion-Related Validity of the Kansas Marital Satisfaction Scale:

The mean responses on the Kansas Marital Satisfaction Scale from 212 wives from intact marriages and 8 wives who had recently separated from their husbands were significantly different. That difference did not appear to be an artifact of social desirability since it decreased only slightly among subjects scoring zero on marital social desirability. The results provide new, if quite limited, support for the criterion-related validity of the marital satisfaction scale. Other characteristics of the scale paralleled previous research, with the new finding that, by controlling for marital social desirability, it was possible to reduce substantially, but not eliminate, some of the nonnormal characteristics of the distributions of the scores.
Current Concepts of Thoracic Surgery in the Management of Lymphoma

Abstract Improved techniques of radiation therapy and chemotherapy have provided a substantial rate of cure or palliation for many patients with malignant lymphoma. A study of 1,036 patients with lymphoma seen during a ten-year period has identified the place of thoracic surgery in the total management of this disease. In 104 patients, thoracic procedures contributed to the diagnosis. A positive diagnosis was made from tissue obtained by scalenus anterior fat pad biopsy, mediastinoscopy, bronchoscopy, or thoracotomy. Because of the nature of lymphoma, crises develop that cause increased debility or that threaten life. When customary treatment is ineffective, several varieties of thoracic operations (including tube thoracostomy, pleurectomy, peri-cardiectomy, and tumor resection) can be employed. Twenty-five of 39 patients for whom a surgical procedure was carried out have had their life prolonged or have been cured.
Discussion of sexual risk behavior in HIV care is infrequent and appears ineffectual: A mixed methods study

Consensus guidelines in HIV care call for clinicians to provide a brief sexual risk behavioral intervention in each visit. Studies based on participant reports find this occurs infrequently, but studies based on direct observation of clinical encounters are lacking. We conducted a mixed method study that used audio recordings of 116 routine outpatient visits by 58 different patients with HIV, in five different practice sites. Transcripts of the visits were coded and analyzed using a quantitative system. In addition, we conducted a qualitative analysis of the dialogue segments in which sexual risk behaviors arose as a topic. Discussion of sexual risk behavior occurred in 10 visits, and was generally quite brief. Two visits featured substantial counseling about sexual risk reduction; two others included substantial discussion which was not evidently directed at the patient’s changing behavior. Cues suggesting a need or opportunity for such discussion that physicians did not follow up on occurred in seven additional visits. Interactions about sexual risk had less patient engagement than interactions about other health behaviors. Physicians seldom provide sexual risk reduction counseling in HIV care, even where specific indications are present.
Poetic Vividness and Aesthetic Preference: Individual Differences in Poetry Writing Styles

Sutnmary.-Preference for visual complexity is shown to be correlated with an imagistic and metaphoric style of writing poetry for individuals participating in a poetry therapy group. Understanding individual dlfferences in poetic style has preoccupied philosophers and literary theoreticians since antiquity. Seneca, the Roman stoic philosopher, asserted that "Man's speech is just like his Me" in his epistle on Style as a Mirror of Character (Gummere, 1971). He then proposed that one's manner of verbal expression directly reflects one's temperament. This putative relationship between expression and personality has not been well stuled from an empirical perspective, even though psychology offers strong methodological techniques for investigating such dlfferences. One potentially useful distinction for exploring this, first developed by the hguist Jakobson with Halle (1956), is the contrast between metaphoric and metonymic language. Metaphoric discourse relies on the associative similarities between words whereas metonymic lscourse relies on the realistic, narrative development of events. Martindale (1975), in his study of historical transitions in poetic style, derived from poetic content a dimension he termed primary versus secondary process. Comparing this to Jakobson's work, we may conceive Martindale's primary process factor as expressing metaphoric, imagistic, and polysemic poetic styles. The secondary process parallels metonymic discourse in its narrative and realistic mode of presentation. Although few have investigated the relationships among poetic style, personality, and preference, several researchers have explored these associations with visual artistic style and preference. Recent findings have indicated that preference for visual complexity as measured by the Barron-Welsh art test is associated with personality traits of emotional expressiveness (Ktng, Curtis, & Knoblich, 1991), psychoticism (Eysenck & Furnharn, 1993), and narcissistic and borderline person&ty disorders (Ktng, Vdleneuve, Post, & Moonshine, 1995). In Bhg, Curtis, and Knoblich (1991), it was conjectured that expressive style is reflected in asymmetries in activation of the left and right cerebral hemispheres. Since the right hemisphere preferentially processes emotional information, visual imagery and metaphoric language, individuals
Rigid Structure from Motion from a Blind Source Separation Perspective

We present an information theoretic approach to define the problem of structure from motion (SfM) as a blind source separation one. Given that for almost all practical joint densities of shape points, the marginal densities are non-Gaussian, we show how higher-order statistics can be used to provide improvements in shape estimates over the methods of factorization via Singular Value Decomposition (SVD), bundle adjustment and Bayesian approaches. Previous techniques have either explicitly or implicitly used only second-order statistics in models of shape or noise. A further advantage of viewing SfM as a blind source problem is that it easily allows for the inclusion of noise and shape models, resulting in Maximum Likelihood (ML) or Maximum a Posteriori (MAP) shape and motion estimates. A key result is that the blind source separation approach has the ability to recover the motion and shape matrices without the need to explicitly know the motion or shape pdf. We demonstrate that it suffices to know whether the pdf is sub- or super-Gaussian (i.e., semi-parametric estimation) and derive a simple formulation to determine this from the data. We provide extensive experimental results on synthetic and real tracked points in order to quantify the improvement obtained from this technique.
OCCURRENCE OF SPROUTS AND SEEDLINGS OF PINYON PINES, ALLIGATOR JUNIPERS, AND GRAY OAKS FOLLOWING HARVEST OF FUELWOOD AND PRESCRIBED BURNING

Abstract Objectives were to determine number and height of sprouts and seedlings following clearcutting of a mesa dominated by pinyon pines (Pinus edulis) and alligator junipers (Juniperus deppeana) in southwestern New Mexico and to determine effects of prescribed burning for control of sprouts and seedlings. No stump of pinyon pine sprouted. Nearly 50% of stumps of alligator junipers sprouted with most occurring in plots with slash removed; the fewest and tallest sprouts occurred in plots with slash uniformly scattered following clearcutting. Nearly 25% of stumps of gray oaks (Quercus grisea) sprouted. Burning in the same year as clearcutting did not affect sprouting of gray oaks as much as other treatments. Not burning clearcuts and leaving slash scattered resulted in the fewest sprouts, and shortest sprouts of gray oaks occurred in plots with slash removed. Seedlings of pinyon pines, alligator junipers, and gray oaks were most prevalent in uncut control plots. Some seedlings of alligator junipers were ...
Real-Time Unsteady Loads Measurements Using Hot-Film Sensors

Several flight-critical aerodynamic problems such as buffet, flutter, stall, and wing rock are strongly affected or caused by abrupt changes in unsteady aerodynamic loads and moments. Advanced sensing and flow diagnostic techniques have made possible simultaneous identification and tracking, in real-time, of the critical surface, viscosity-related aerodynamic phenomena under both steady and unsteady flight conditions. The wind tunnel study reported here correlates surface hot-film measurements of leading edge stagnation point and separation point, with unsteady aerodynamic loads on a NACA 0015 airfoil. Lift predicted from the correlation model matches lift obtained from pressure sensors for an airfoil undergoing harmonic pitchup and pitchdown motions. An analytical model was developed that demonstrates expected stall trends for pitchup and pitchdown motions. This report demonstrates an ability to obtain unsteady aerodynamic loads in real-time, which could lead to advances in air vehicle safety, performance, ride-quality, control, and health management.
Physical properties of aqueous glycerol solutions

Abstract Use of aqueous glycerol solutions provides a convenient approach for investigation of a variety of aspects of two phase flow phenomena in porous media concerned with viscosity. These include the scaling of spontaneous imbibition and the forced displacement of one phase by another such as in waterflooding. Glycerol/water solutions provide variation of aqueous phase viscosity by over three orders of magnitude. Physical properties, commonly needed in studies of multiphase flow in porous media, are reported for aqueous solutions of glycerol. They include density, surface tension (against air), interfacial tension (against three types of refined oil), contact angle (against n-decane), and viscosity. Experimental results were obtained at six temperatures (20, 30, 40, 50, 65 and 80 °C) and five levels of ionic strength of the brine used for adjusting the glycerol/brine mixture. Contact angle measurements against n-decane were made at 20 and 60 °C. Glycerol is miscible with water at all investigated salinities and temperature levels. Density and surface and interfacial tensions against refined oils are very close-to-linear with respect to weight fraction of glycerol. Aqueous glycerol solutions on quartz surfaces exhibited zero contact angle (perfect wetting) against both air and refined oil. Increase in viscosity of glycerol–water mixtures with addition of glycerol is highly non-linear. All viscosity data were fitted exceptionally well by an equation originally developed for colloidal dispersions. Literature data on vapor pressure, refractive index and viscosity are also presented.
Nucleoside changes in tRNAs from Bacillus subtilus treated with 5-fluorouracil

Abstract Extensive amounts of 5-fluorouridine and lower levels of 5-fluorocytidine are incorporated into tRNAs from Bacillus subtilus grown in the presence of 5-fluorouracil. Nucleoside analyses revealed both pseudouridine and 5-methyluridine levels to be reduced more extensively at low levels of analog incorporation than could be accounted for by a stoichiometric replacement, as observed earlier with Escherichia coli.
Giant Cell Fibroblastoma of the Vulva at the Site of a Previous Fibroepithelial Stromal Polyp: A Case Report

AbstractBackground.Giant cell fibroblastoma (GCF) is an unusual soft tissue tumor, occurring predominantly in infants and children, and rarely in adults. Giant cell fibroblastoma develops de novo in the dermis or subcutis with a predilection for the extremities, the abdominal and chest walls, umbili
AMERICA'S CONFIDENCE IN FREEDOM

Abstract Freedom is a cherished American value, a value that is vital because where freedom is enhanced, security also increases. The United States plays an essential leadership role in the world, on issues such as religious freedom and human trafficking. The United States is committed to supporting the democratic aspirations of all, and though it is far from perfect, America cannot shirk its responsibility as a global leader in the fight for freedom.
Electrophysiology of "epileptic" neurons: spike generation.

Abstract 1. 1. Intracellular recordings were obtained from 74 neurons in penicillin-induced epileptogenic foci on cat pericruciate cortex in order to study the mechanisms of spike generation in “epileptic” neurons. Spontaneous and evoked spike discharge and spiking associated with the large depolarization shifts (DSs) which occur in cells during inter-ictal epileptiform surface events were examined. 2. 2. Orthodromic and antidromic spike generation (14 PT cells) was generally normal in that the usual IS-SD spike components were demonstrated and spikes arose from stable firing levels. Direct depolarizing current pulses produced high frequency spiking without DS generation. 3. 3. Antidromic spikes elicited during a DS did not alter the DS amplitude or time course. Antidromic invasion failed during the peak of the DS in some cells, due to cathodal blockade and also during periods of high frequency DS spike generation, presumably because of refractoriness or collision in the axon. 4. 4. Peculiarities of spike generation occurred as follows: (1) In 19 cells the first DS spike sometimes arose from a membrane potential 2–10 mV below the usual firing level without a preceding slow pre-potential. (b) In 4 of these cells orthodromic spikes not associated with the DS also occasionally arose from below threshold and appeared to have more than one mode of onset. (c) In 3 neurons, intracellular negative or negative-positive spikes occurred during surface epileptiform discharges. (d) Partial spikes or “spiklets” in addition to spikes of normal amplitude were noted in 18 cells of the focus and 4 of 28 control cells from normal cortex. 5. 5. These pecularities of spike generation suggest that in proportion of neurons of the penicillin epileptogenic focus, impulses originate from trigger zones distant from the soma, presumably from dendrites. These data raise the possibility that dendritic spike generation may be a general property of “epileptic” neurons.
Squamous cell carcinoma of head and neck in patients with well-differentiated lymphocytic lymphoma

Seventy-six cases of well-differentiated lymphocytic lymphoma (WDLL) were reviewed for evidence of additional malignancies. Of these, 18 patients (24%) had one to three further tumors; one half (nine) had squamous cell carcinoma (SCC). The head and neck area was the primary site in all but one case of SCC. The carcinomas were frequently multiple, recurrent, and clinically aggressive. The tumors showed unusually poor differentiation histologically. Actinic keratosis and basal cell carcinomas were frequently associated with SCC. Fifty percent metastasized to cervical lymph nodes replaced by WDLL. Lymphadenopathy due to metastatic SCC may be mistaken for malignant lymphoma alone. In two of five patients (40%), death was directly attributable to SCC. As in renal transplant recipients, SCC of the head and neck in WDLL patients is a common cause of significant complications and mortality requiring aggressive management. Immunosuppression due to WDLL and/or to chemotherapy is likely an important predisposing factor in combination with sun exposure.
Varied Meanings and Practice: Teachers' Perspectives regarding High School Inclusion

This study examines teachers perspectives in a ninth grade class that included students with disabilities in regular classes. Observations and interviews yielded data on how the teachers thought about inclusion of students with disabilities in their classes, and how they thought about a student with Down syndrome who was also in their class at the time of the study. Data collected over 7 months of a school year included variability in the interpretations and practice of inclusion and varied expectations for some students with disabilities. Teachers who supported inclusion of the student with Down syndrome differed in their expectations of him and the other students with and without disabilities. Variable standards for classroom attendance was a primary example. Findings suggest the importance of further research into the meanings and practices of inclusion as they relate to perceived purposes of schooling, the application of structures supporting inclusion in high schools, and the merging of social and ac...
Approach to the Patient With Recurrent Infections

Children with a history of recurrent or unusual infections present a diagnostic challenge. Differentiation between frequent infections caused by common risk factors, versus primary immune dysfunction should be based on a detailed history and physical examination and, if indicated, followed by appropriate laboratory studies. A high index of suspicion could lead to an early diagnosis and treatment of an underlying immune deficiency disease. This article presents to physicians an approach to the evaluation of children with recurrent infections. Important details from the history and physical examination, and an appropriate choice of screening laboratory test to be ordered in a given situation are discussed.
The determination of geoacoustic models in shallow water

A technique for determining geoacoustic models in shallow water is described. For a horizontally stratified ocean and bottom, the method consists of measuring the magnitude and phase versus range of the pressure field due to a CW point source and numerically Hankel transforming these data to obtain the depth-dependent Green’s function versus horizontal wavenumber. In shallow water, the Green’s function contains prominent peaks at horizontal wavenumbers corresponding to the eigenvalues for any trapped and virtual modes excited in the waveguide. A geoacoustic model for the bottom is obtained by computing the theoretical Green’s function for various values of the bottom parameters and determining the parameter set which provides the best agreement with the experimental Green’s function, particularly in the positions and relative magnitudes of the modal peaks. Comparisons are also made between the measured and theoretically computed pressure field magnitudes. The technique is demonstrated using experimental data at 140 Hz and 220 Hz.
Children's Individual Experiences in Early Care and Education: Relations With Overall Classroom Quality and Children's School Readiness

This study examined relations among children's individual experiences, global classroom quality, and school readiness. Preschool children from low-income backgrounds (N = 138; M = 62.16 months; SD = 3.93; range = 55−70) were observed in their early care and education settings, and their language and cognitive skills were assessed. Research Findings: Individual children in classrooms with small group sizes had higher quality individual experiences even though global classroom quality was not necessarily better. Higher levels of global classroom quality did not ensure that every child in the classroom was engaged fully in available interactions and activities. Children with disabilities were generally enrolled in classrooms with higher global quality and had higher quality individual experiences than those without disabilities; however, children without disabilities enrolled in these inclusive classrooms did not necessarily have a higher level of individual experiences than those in non-inclusive classrooms...
Drug Discovery from Marine Microbes

The marine environment has been a source of more than 20,000 inspirational natural products discovered over the past 50 years. From these efforts, 9 approved drugs and 12 current clinical trial agents have been discovered, either as natural products or as molecules inspired from the natural product structure. To a significant degree, these have come from collections of marine invertebrates largely obtained from shallow-water tropical ecosystems. However, there is a growing recognition that marine invertebrates are oftentimes populated with enormous quantities of “associated” or symbiotic microorganisms and that microorganisms are the true metabolic sources of these most valuable of marine natural products. Also, because of the inherently multidisciplinary nature of this field, a high degree of innovation is characteristic of marine natural product drug discovery efforts.
Monte Carlo calculations of a bismuth germanate scintillation detector

Abstract Intrinsic efficiency, radial distribution of deposited energy and other properties of importance were investigated for bismuth germanate slabs via Monte Carlo calculation. The calculations were done for different slab thicknesses in the range 1 8″–2″ , and over the energy range 140–999 keV. An examination of the data shows the possible advantage of the use of BGO as scintillation detector for high energy gamma ray and positron imaging. The data do not show very strong dependence of the image resolution on the thickness of the slab.
Modification of the Mehlich Lime Buffer Test

Routine use of the Shoemaker, McLean, and Pratt (SMP) lime buffer method resulted in chronic problems with electrode reference junction degradation, stability of readings relative to contact time, and generation of hazardous waste. During method recalibration, the Mehlich buffer was chosen for parallel evaluation with SMP, with the goal of improving method performance and eliminating of hazardous waste. The Mehlich buffer was modified by substituting calcium (Ca) for barium (Ba). The modified Mehlich (MM) buffer was found to be identical to the original with respect to buffering power and linearity over an extended pH range of 3.0–6.6. Seven agronomic soils were incubated with eight rates of calcium carbonate for 90 days. Regression analysis was performed to predict lime requirement (LR) to several target pH levels, based on pH measured in each buffer alone or in both water and buffer. Slightly better predictability was obtained using multiple regressions, with R2>0.95 in all cases. Significant but minor ...
Trace metal composition of Green River retorted shale oil

Abstract Crude shale oils from an aboveground and two in-situ retorting processes were characterized for 26 trace element constituents. The shale oils were pyrolysed from Green River Formation oil shale by pilot plant or semiworks-sized facilities. Trace elements were resolved into those predominantly associated with suspended shale fines or emulsified water, and those more intimately associated with the shale oil matrix. The abundance of the metals As, Co, Fe, Hg, Mo, Ni, Sb, Se, V and Zn were quantified in whole and fractionated shale oil samples; the possible chemical nature of several metals is discussed. Based on the shale oils examined, the following observations were noted: the shale oils contained moderately high levels of Fe (33–63 ppm) and As (9.3–29 ppm), and lower quantities of Co, Mo, Ni, Se and Zn (≈1–10 ppm); most trace metals were associated with asphaltene or resin components; relative to reported mean values for petroleum, the As, Co, Fe, Mo and Se were more prevalent in Green River shale oil; in-situ retorting processes appeared to introduce Mo into the product shale oil.
Drugs on the Horizon for Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer death in the United States, and research advances over the past 20 years have allowed us to better understand the molecular mechanisms underlying both tumorigenesis and resistance to therapy. As a result, there are a wide range of novel agents currently under development that we anticipate will enter the clinical arena within the coming years. This review seeks to discuss a spectrum of key pathways and agents that may be particularly relevant to the treatment of CRC in the near future, as well as briefly discuss some of the challenges we face in this new era of drug discovery.
Making indirect calorimetry a gold standard for predicting energy requirements for institutionalized patients.

The recent study by Boullata and colleagues (1) showed that predictive equations for resting metabolic rate (RMR) in hospitalized patients have errors of 10% in slightly more than one in three hospitalized patients. These results are in agreement with those from other studies that have also shown that prediction errors are not uncommon in patients (2), particularly in trauma patients (3). Even in healthy subjects, predictions also may fail when applied at the individual level (4), an error that can often, but not totally, be explained by individual deviations in body composition (5). These findings of Boullata and colleagues (1), as well as others, are highly relevant in institutionalized patients because a mismatch of prescribed energy intake and expenditure can have significant effects on a patient’s ultimate outcome (6). IMPORTANCE OF ACCURACY The value of an accurate assessment of RMR rests on the realization that measured or predicted RMR is the major parameter used in prescribing the energy intakes for enteral or parental nutrition. The RMR is the primary variable in prescribing energy intake because it is the largest single component of total energy expenditure in hospitalized patients. Long (6) determined that total energy requirement averaged only 1.2RMR, compared with 1.6RMR in healthy, free-living individuals, because of reduced levels of physical activity (7). Healthy individuals spending time as inpatients as part of research studies generally fall between these two estimates, with total energy expenditures averaging 1.4 to 1.5RMR; however, such inpatients generally control their own energy intakes and are not under the registered dietitian’s care, and as such it is the inpatient with an energy expenditure of about 1.2RMR and who is unable to control his or her own energy intake that is the primary concern with regard to predicting energy requirements. The concern over the errors in predicting RMR arises because energy expenditure is the determinate of energy needs and the reference point for overfeeding or underfeeding the patient. Overfeeding of energy, particularly with high glucose intakes, can induce hyperglycemia, insulin resistance, fatty liver, and, in ventilated patients, ventilator dependency (5). Conversely, underfeeding with regard to energy can result in increased loss of muscle mass, cachexia, reduced immune response, and decreased organ function (5).
Effect of chlorpromazine on rat brain phosphorylase

Abstract The effect of chlorpromazine on the phosphorylase level of rat brain differs according to the mode of sacrifice. When control rats are sacrificed by immersion in liquid nitrogen, the level of brain phosphorylase is lower than when the rats are sacrificed by inhalation of chloroform. Chlorpromazine depresses the phosphorylase level of rats immersed in liquid nitrogen but enhances the enzymatic activity of brains of rats sacrificed with chloroform. The enhancing effect produced by chloroform on the enzyme level as well as the further enhancing effect of a pretreatment with chlorpromazine are not peculiar to chloroform, since the same effects can be reproduced by nitrogen gas asphyxia. Since chloroform and nitrogen gas cause respiratory arrest, this could be a common mode of action of the two agents on brain phosphorylase.
Compacts of powdered material as porous bodies for use in sorption studies

Details are given for the production of rigid porous bodies (compacts) made by compacting under high pressure fine powders in the particle range of 10—0·01μ of silica, calcium carbonate, plaster of Paris and molecular sieves. These compacts were used as samples to study sorption and related dimensional changes. The results were used to compute spreading pressure by applying the Gibbs adsorption equation and allowed derivation of the Δl/l vs φ plots using the Bangham relation. With compacts made from molecular sieves, it was possible to study the forces imposed on the particles by water entering or leaving the micropore system.
Use of Statistical Energy Analysis for Rotating Machinery, Part II: Coupling Loss Factors Between Indirectly Coupled Substructures

Abstract Indirect coupling between physically uncoupled substructures is present when either the coupling between the directly coupled substructures is strong, or the sizes of the substructures are small compared to the wavelength, or the junction between the substructures is in the near field of another junction. The coupling loss factors between indirectly coupled structures are generally not taken into account in traditional Statistical Energy Analysis (SEA). In this paper, theoretical expressions are developed for calculating the indirect coupling loss factors between physically uncoupled substructures. The derived formulae show that the indirect coupling loss factors, when compared to the direct coupling loss factors, are signficant if strong direct coupling exists between the substructures. However, the indirect coupling loss factors are negligible if weak coupling exists between any two coupled substructures. A series of experiments are carried out to verify the theoretical analysis for the determination of the indirect coupling loss factors. Also, the influence of the indirect coupling loss factors on the response of a complex machine structure, predicted using SEA, is demonstrated. Better agreement between the predicted results and the directly measured results is obtained when the indirect coupling loss factors are included in the SEA model.
Crosscorrelation kernels in acoustic Green's function retrieval by wavefield correlation for point sources on a plane and a sphere

SUMMARY The far-field approximation is commonly assumed in the derivation of Green's function retrieval by wavefield correlation using reciprocity theorems. This approximation can result in erroneous amplitude of the retrieved seismic phases and generate artificial arrivals. In an open system, we show that the far-field approximation can be removed by the exact integral equation method and this leads to the crosscorrelation kernel. In previous work, kernels in 2-D space had been explicitly constructed. With the kernel, we can construct the Green's function by crosscorrelation even when the sources are not in the far field. Here we extended the 2-D case to 3-D for acoustic waves for point sources on a plane and on a sphere. For the spherical case, the kernel is expressed by spherical harmonics and it degenerates to the Dirac Delta distribution under the high-frequency case; however, for a fixed frequency, if we increase the radius of the sphere, it reduces to that of the plane boundary.
Link adaptation on aggregated TVWS channels

The availability of Television White Space (TVWS) [1] has attracted considerable attention in industry and academia. Given the relatively small amount of bandwidth allocated to each TVWS channel (e.g., 6, 7 or 8 MHz), and the non-contiguous nature of the availability, channel aggregation ([2], [3]) is an attractive way to make full use of the available TVWS spectrum and achieve higher throughput. In this paper we propose and analyze several link adaptation schemes in the context of MAC layer aggregation. We first analyze the SINR conditions of multiple aggregated channels using a model of a modified 802.11n system that supports TVWS operation. Then, we investigate three different link adaptation mechanisms and compute their MAC layer throughputs. Our results show that the SINR variance on the aggregated channels can be high, mainly due to the unique characteristics of TVWS spectrum, i.e., different maximum transmit powers imposed on different types of TVWS channels, and significant Digital TV (DTV) out-of-band emissions to adjacent TVWS channels. Both analytical and numerical results show that independent link adaptation based on each channel SINR provides much higher throughput than the single adaptation schemes, where a common rate is applied on the aggregated channels.
Rapid radiative transfer model for AMSU/HSB channels

The atmospheric transmittance model for the Advanced Microwave Sounding Unit-A (AMSU-A) and the Humidity Sounder for Brazil (HSB) channels on the Aqua spacecraft uses a polynomial approximation to the temperature dependence of oxygen-band opacity within atmospheric layers. It uses lookup tables to calculate local water-vapor line intensity and pressure-broadening parameters as well as contributions to absorption from the water-vapor continuum, distant lines, and cloud liquid water. The algorithm includes water-line self-broadening and the magnetic-field effect on AMSU-A channel 14. The microwave surface emission model is based on a preliminary classification of the surface type, with subsequent adjustments to the emissivity spectrum that are obtained from the retrieval algorithm. A simple approximate correction for surface nonspecularity is included. The algorithm has been tested by comparisons to a line-by-line calculation and to measurements made by the NOAA-15 AMSU-A.
Cevalent attachment of lactoperoxidase to polystyrene tissue culture flasks

Abstract In the present study a method is developed whereby lactoperoxidase is covalently coupled to polystyrene tissue culture flasks and is used to radioiodinate monolayer cell proteins that come into intimate contact with the surface. Coupling was effected by the reaction sequence: (i) nitration using HNO 3 H 2 SO 4 , (ii) reduction with sodium hydrosulfite, (iii) simultaneous incubation with lactoperoxidase and dimethylsuberimidate dihydrochloride. Each step was monitored by differential infrared spectroscopy. Either enzyme activity or total protein binding could be optimized. Iodination of intact mouse L cells attached to this surface was efficient, and the distribution of labeled trichloroacetic acid-precipitable material indicated preferential incorporation into extracellular sites.
Innovative Introduction to Civil Engineering Curriculum

Many undergraduate teaching institutions have modified their civil engineering curricula to incorporate technical and philosophical innovations into their programs. The modifications range from modest changes in course content to new sequences of interwoven and complementary courses. Villanova University’s new civil engineering curriculum retains a core of courses in five basic disciplines: environmental engineering, structures, transportation engineering, hydraulics and hydrology, and geotechnical engineering. The curriculum includes a new introductory course, “Civil Engineering Measurements,” that is designed to stimulate the students’ interest and introduce them to the five disciplines. The course draws on the students’ knowledge of physical science and allows them to use these principles in quantifying data they derive from working on practical problems and projects. Most of the course is centered around two major team projects: an environmental study of a local stream and a model truss. The course was introduced in fall 1992 and appears to have been successful in stimulating and motivating the students as well as preparing them for their subsequent studies.