cssi/SciSciGPT-SciSciNet huggingface dataset:
Interference coatings for neutrons.

A review of multibilayer thin film devices for monochromating and/or polarizing neutrons with wavelengths of the order of 1A and longer is given.
Customer Value Change in Industrial Marketing Relationships - A Call for New Strategies and Research

Abstract Relationship marketing is critical to both researchers and practitioners because it addresses issues aimed at retaining customers. Strategic customer retention is problematic and requires information from customers concerning: (1) what they value (need) now, (2) their satisfaction with suppliers' abilities to deliver that value, and (3) how their perceptions of value are changing. Currently there is little theoretical understanding of, and thus less than perfect normative advice for dealing with, the third issue. This article addresses this gap by presenting an argument for developing a customer value change theory and proposing a model that incorporates those events likely to trigger changes in three forms of value: values, desired value, and value judgements. The concepts presented build on current business efforts to predict what customers will want in the future, as well as on customer satisfaction and value research.
Terahertz Pioneer: Paul L. Richards

As the son of Lorenzo A. Richards [1], a well-known physicist, and pioneer in Soil Physics, and with seven uncles holding Ph.D. degrees, perhaps it was inevitable that Paul Linford Richards1 would find himself choosing a career in science. However much this may have been favorably influenced by his relationship with his family, it was not forced upon him, for as he told me, his father insisted that he, Paul, spend appropriate apprentice time with individuals practicing alternate professions before he chose to enroll in Harvard and to begin a long and stellar career in physics. We should all be very happy that his own force of will, innate talents, and strong desire to take the path less trodden, placed him in a position to have such a profound and widespread impact on Terahertz science and the instrument and device technologies that are so commonly employed today throughout our field.
Electronic structure and properties of the high-Tc superconductors: Tl2Ba2CaCu2O8 and Tl2Ba2Ca2Cu3O10

Abstract We present results of highly precise local density calculations of the electronic structure of the two high- T c superconductors Tl 2 Ba 2 CaCuO 8 ( T c ≅112 K) and Tl 2 Ba 2 Ca 2 Cu 3 O 10 ( T c ≅125 K), as obtained with the full potential linearized augmented plane wave (FLAPW) method. A relatively simple band structure is found near E F and strong 2D properties are predicted. Again as in the case of the other high- T c materials, Ba and Ca are highly ionic, with the Ca 2+ ions insulating the Cu-O planes. The Tl-O complexes, which are decoupled from the Cu-O planes, produce small electron pockets at E F with predominant O character that contribute to the transport properties. Each Cu-O plane is found to contribute ≃ 1 state/(eV-Cu atom) to the density of states (DOS) at E F , similar to the Bi 2 Sr 2 CaCu 2 O 8 case. Remarkable strong fermi surface nesting is found along the (100) and (010) directions for the 2D Cu-O dpσ bands. Significantly, we show that the usual simple nearest-neighbors only tight-binding model cannot properly describe these states. Crude rigid ion calculations show that a purely electron-phonon mechanism is inadequate to explain the observed high T c . As in the case of the other high- T c superconductors, a charge transfer excitation (excitonic) mechanism appears likely. Interestingly, the partial DOS structure shows that both systems can be viewed as a metal-semiconductor (or metal-semimetal) superlattice indicating a possible relation to the Allender, Bray, and Bardeen model of excitonic superconductivity.
Emerging, fungal pathogens in immunocompromised patients : classification, diagnosis, and management

Fungi such as Fusarium species, Trichosporon species, Curvularia species, and Alternaria species previously were thought to represent contamination or harmless colonization when isolated from immunocompromised patients. More recently, the pathogenic role of these and other fungi has been clearly established. Three diverse groups of fungi are responsible for these emerging infections: the agents of phaeohyphomycosis and hyalohyphomycosis and certain yeasts. Reports of the emergence of these organisms as significant pathogens may be ascribed to increasing awareness by physicians and microbiologists, aggressive culture of patient specimens, increasingly cytotoxic chemotherapy, and selection of resistant organisms by the widespread empirical use of amphotericin B
Creatine kinase in developing skeletal and cardiac muscle of the rat.

Abstract This paper reports the changes in specific activity and isoenzyme pattern of creatine kinase in skeletal and cardiac muscle of Holtzman rats during development. There is a rapid accumulation of enzyme after day 17 of gestation and, starting at a slightly earlier time, a transition from “brain” to “heart” and then to predominantly “muscle” isoenzyme takes place. Although the changes are similar in the two types of muscle, important differences are found. The specific activity of creatine kinase is much lower in developing and mature cardiac muscle, but adult levels of the enzyme are approximated sooner in cardiac than in skeletal muscle tissue. The changes in isoenzymes are more gradual and less profound in cardiac muscle than in skeletal muscle. The factors which may relate to these striking changes in creatine kinase are discussed.
Explaining behavior: Bringing the brain back in

What is needed today is a biologically grounded explanation of behavior, one that moves beyond the so‐called mind‐body problem. Yet no solution will be found by philosophers who refuse to learn about how brains and bodies work, or by neuroscientists pursuing experimental research based on outmoded or blatantly anti‐biological theories. Churchland's book proposes a solution: to come by a unified theory of the mind‐brain philosophers have to work together with neuroscientists. Yet Churchland's vision of a unified theory is based on an assumption that, while widely held, may not adequately reflect brain functioning in the production of behavior, namely, the assumption that brain processes represent. The present paper proposes an alternative view, suggesting that patterns of neural activity do not ‘represent’ anything, that brains do not ‘read’ or ‘transform’ representations, and that brains do not require representations to produce goal‐directed behavior. Representations are replaced by self‐organizing neura...
Plant Nitrogen Status and Boll Load of Cotton

Nitrogen management is important in determining cotton (L.) yield and fiber quality. Plant tissue tests are often used to estimate cotton N status and determine if further fertilization is needed during the growing season. This study was conducted to examine the relationship between plant tissue tests of petiole NOa concentration and leaf N content and cotton performance as measured by vegetative growth (i.e., leaf area) and boll load. Nitrogen rates of 0, 18, 36, 72, and 144 ram N pot were applied at 2-wk intervals beginning 13 and 26 d after emergence in 1987 and 1988 through boll maturity to a greenhousegrown cultivar, Stoneville 213. The strong relationship between leaf N and leaf area and boll number (= 0.80 and = 0.89) 1 wk after first flower appearance suggests that the transition period between vegetative and boll development is a critical time to assess cotton's N status in relation to yield. Nitrogen deficits had little effect on boll weight, boll period duration, and number of main stem nodes. Although boll weight decreased with increasing N deficit, final boll weight of the high-N plants were within 20% of the plants receiving low N supply. The relationship between leaf N and petiole NO content, was best described by = a + ; however, with this function only one-half of the variation in leaf N was accounted for by variation in petiole NO content (= 0.48). Leaf area and boll number were poorly correlated with petiole NO content. Leaf N content was a better predictor of cotton vegetative growth (as indicated by LAI) and boll number than petiole NO content, particularly when measurements are made 1 wk after first flower.
DIRECTIONAL CORRELATION OF FISSION FRAGMENTS AND PROMPT GAMMA RAYS ASSOCIATED WITH THERMAL NEUTRON FISSION

Prompt fission $\ensuremath{\gamma}$-ray intensity as a function of the angle from the fragment direction has been measured for the thermal neutron fission of ${\mathrm{U}}^{233}$, ${\mathrm{U}}^{235}$, and ${\mathrm{Pu}}^{239}$. For each of these three nuclides, the fission $\ensuremath{\gamma}$ rays were found to be emitted preferentially in the direction of fragment motion by as much as 15%. It was found that the experimental data were best fitted by assuming that $\ensuremath{\gamma}$ rays emitted by fission fragments have two components with different angular distributions. One component, accounting for about 85% of the $\ensuremath{\gamma}$ rays, was isotropic about the fission fragment direction. The remaining 15% had the angular distribution of $\ensuremath{\gamma}$ rays from quadrupole transitions of nuclei having approximately 7 units of angular momentum distributed in, or near, a plane perpendicular to the direction of fragment motion. A calculation of the torque resulting from electrostatic forces between the fission fragments is discussed. Results of this calculation indicate that these electrostatic forces could give rise to the fragment rotations indicated by the $\ensuremath{\gamma}$-ray measurements.
Au(111) and Pt(111) surface phase behavior

Abstract We describe our recent X-ray scattering studies of the structure and phases of the clean Au(111) and Pt(111) surfaces. Below 0.65 of their respective bulk melting temperatures, the Au(111) surface has a well-ordered chevron reconstruction and the Pt(111) surface is unreconstructed. Above these temperatures, both surfaces reconstruct to form layers that are isotropically compressed and have only short-range order. Throughout their reconstructed phases, the densities of the Au and Pt(111) surfaces increase with increasing temperature.
Agent-based geometry optimization with Genetic Algorithm (GA) for tall apartment’s solar right

Abstract In East Asia, whether it is based on cultural or physiological needs, most residents prefer a dwelling space that has a certain amount of natural, direct sunlight to ensure their comfort. For example, in Korea, this need led to the development of building codes requiring most residential buildings to provide sunlight. As a result of following the code, most tall apartment buildings exhibit similar building layouts in which major facades face south, thereby sacrificing design diversity, creativity, and identity. To ease the problem, this paper proposes an alternative method for optimizing a building’s access to direct sunlight. The proposed method uses an agent-based geometry control system that sets parameters to control a building in a hierarchical manner, which introduces relatively less control points than the typical parameters used in Genetic Algorithm (GA) optimization. This method allows for both a reduction in the computational cost and time required to determine a solution as well as the possibility to integrate with computational simulation tools that provide the ability of finding a more accurate and objective performance value. Unlike current code, which requires users to follow certain rules as a prerequisite, the proposed method uses performance driven measures to satisfy the requirement thereby allowing for more varied design possibilities to layout tall apartment buildings.
The response of low-rise non-engineered structures to extreme wind conditions

Abstract In 1984 over US $250 million worth of damage was caused by two severe storms in the states of North and South Carolina. In March a series of tornadoes caused the majority of the damage and killed 57 people. In September, Hurricane Diana came ashore near the border between the two states but due to a fortuitous set of meteorological and legislative conditions the damage was relatively minor. The tornadoes passed through an area where strong winds are relatively rare and building codes are generally poorly enforced or non-existent. Hurricane Diana struck an area which had previously experienced a number of severe hurricanes. As a consequence of this an extremely stringent and specific residential building code had been developed and enforced. This paper uses a survey of the damage in these two storms to assess the extreme wind performance of non-engineered structures, i.e. those that derive their structural form from tradition or legislation. It considers the weaknesses in traditional forms of timber and masonry construction, examines the advantages to be gained by appropriate legislation and makes recommendations for improving the wind-resistance of such structures.
Level set estimation with dynamic sparse sensing

In this paper, we study the level set estimation of a spatial-temporally correlated random field by using a small number of spatially distributed sensors. The level sets of a random field are defined as regions where data values exceed a certain threshold. We propose a new active sparse sensing and inference scheme, which can accurately extract level sets in a large random field with a small number of sensors strategically and sparsely placed in the random field. In the proposed active sparse sensing scheme, a central controller dynamically selects a small number of sensing locations according to the information revealed from past measurements, with the objective to minimize the expected level set estimation errors. The expected estimation error is explicitly expressed as a function of the sensing locations, and the results are used to formulate optimal and sub-optimal selection of sensing locations. Simulation results demonstrate that the proposed algorithms can achieve significant performance gains over baseline passive sensing algorithms that do not proactively select the sensing locations.
Infrainguinal Revascularization in End-Stage Renal Disease

Patients with end-stage renal disease are being maintained for longer periods with dialysis or renal transplantation. Although renal failure itself is associated with occlusive peripheral vascular disease, such patients often have additional comorbid risk factors. In this series, 88% of patients were diabetic, 93% were hypertensive, and 44% were smokers, all factors that exacerbate the severity of their vasculopathy. As a consequence, the vascular surgeon is increasingly being confronted with limb-threatening peripheral vascular disease in this population. We performed 34 infrainguinal bypasses in 27 patients during an 8-year period from 1986 to 1993. Fifty percent of these were bypasses to the infrapopliteal level. The 12- and 48-month graft patency was 64% and 38%, respectively, by life-table analysis. The limb salvage rate was 65% and 58% at 12 and 48 months. The perioperative mortality rate was 5.9% and the morbidity rate was 37%. Most of the limb loss (66%) occurred during the first 3 months after surgery as a result of acute graft occlusion or nonhealing of an ulcer or minor amputation site. We believe that this reflects an increasingly aggressive approach to limb salvage in patients with end-stage renal disease. Four limbs were lost despite a patent graft. Infrainguinal bypass is a viable management option for limb salvage in patients with end-stage renal disease. These procedures can be undertaken with acceptable perioperative mortality and with a 12-month limb salvage rate of 65%.
PREDICTION OF ICE ACCRETION ON WIND TURBINE BLADES: A USER-FRIENDLY SOFTWARE

It has been recognized that many models predicting ice accretion on wind turbine surfaces fail to predict the shape of horned ice accretion correctly while the results for rime type ice are fairly reasonable. One of possible sources of discrepancy is perhaps due to the fact that these models neglect the ice densification effect occurring during the icing process. To investigate the significance of densification effect, a proper, firstprincipled based analysis is required. This effort will move towards more accurate prediction of ice accretion and their impacts on design for industrial users. This paper presents a Windows based package that allows the user easily to input test conditions and predict the mass accumulated on the wind turbine blades. The software package combines features from a CFD solver, the LEWICE ice accretion code and the densification icing code. A flexible and interactive interface tool is developed using Visual Basic and C programming tools. Discussions are given in details to the definitions of input parameters, theories, iteration scheme and accuracy estimation. A qualitative comparison with available experimental data and prediction by the LEWICE code is also made. NOMENCLATURE c chord length, m d droplet diameter, m g gravitational acceleration, m/s2 h film heat transfer coefficient, W/m2-K hm mass transfer coefficient, W/m -s k thennal conductivity, W/m-K LWC liquid water content, g/m3 m ice mass flux, kg/m2-s
Hierarchy versus inertial cooperation

It is somewhat embarrassing for an economist and economic historian with the usual strong sense of turf and a need to be identified with his own to find his name cropping up from time to time in the "foreign" field of political science. True, the conclusion of my book on the Depression borrowed the concept of leadership from political scientists Norman Frohlich and Joe A. Oppenheimer, who put forth the notion that public goods would be underproduced (because of free riders), unless a leader agreed to bear a disproportionate share of their costs.' My conclusion stated that the 1929 Depression was so wide, so deep, and so long because no leading country was able and willing to discharge the role of a stabilizer. The United Kingdom could not; the United States (with or without the help of France) would not.2 The responsibilities of a stabilizer, as I originally detailed them, were to furnish an outlet for distress goods (or in periods of acute shortage, to share its supplies with highly dependent countries); to maintain the flow of capital to would-be borrowers; and to serve as a lender of last resort in financial crisis.3 (Since that book appeared in 1973, I have added two other responsibilities to the role of a would-be stabilizer of the world economy: to maintain a structure of exchange rates and to coordinate macroeconomic policies.)4 Political science has now transmuted the concept of leadership into "hegemony," a word that makes me uncomfortable because of its overtones of force, threat, pressure. I think it is possible to lead without arm-twisting,
Effect of a surface coating on flexural performance of thermally aged hybrid glass/carbon epoxy composite rods

Abstract Polymer Core Composite Conductors (PCCCs) are subjected in-service to thermal aging which in some cases can be severe. To reduce aging a proprietary fluorinated ethylene propylene (FEP) based surface coating was applied to a hybrid glass/carbon epoxy composite rod used in Aluminum Core Composite Conductors (ACCC®), one type of PCCC. The rods were aged in air at 180 °C for up to 12 months. Surface damage was evaluated using optical and scanning electron microscopes and compared to uncoated rods previously subjected to the same conditions. Subsequently the rods were tested under four point bending to determine their flexural performances as a function of aging time. It was found that the uncoated rods lost significantly more flexural stiffness and strength than the coated rods. To explain the experimental mechanical data a Finite Elements Modeling (FEM) was performed. A new hypothesis is offered to explain the strongly beneficial effect of the coating in maintaining mechanical properties after thermal aging. Thus it appears that FEP or other coatings could be used to significantly reduce thermal aging of glass/carbon epoxy composites and in particular extend the life of PCCCs in service.
Assessing initial anticipatory public relations socialization of early mass communication entrants

Abstract Differing from previous research of PR majors, this study of students in introduction to mass communication courses focused on how one is socialized into public relations before he or she arrives for the first day on the job. The 236 students surveyed most frequently associated public relations with advocacy roles, working with people and advertising. Experience on high school newspapers and yearbooks were both positively related to a student's public relations technician self-efficacy.
The nature and origin of a class of essential gene substitutions in bacteriophage λ

Abstract Particles containing extra DNA are found in high-titer stocks prepared by growth of the λ deletion mutants λb221 and λb221 imm434 (−21.9 and 24.1% λ DNA, respectively). We have found that stocks of λb221 contain, in addition to the phage with tandem duplications previously reported (Emmons, S. W., MacCosham, V., and Baldwin, R. L. (1975). J. Mol. Biol. 91, 133–146), a low level of stable addition and substitution mutants that result in an increase in DNA content. The substitution mutants are present at a higher frequency in stocks of λb221 imm434, where they are readily identified by their density in CsCl and their characteristic plaque morphology. Electron microscopic examination of heteroduplex DNA shows that the substitutions contain DNA related to the p4 substitution. A number of strains of Escherichia coli K12 have been examined for their ability to yield this fragment of DNA. We find that λ with the p4-like substitution was present in stocks of λb221 imm434 grown on most strains but was absent in stocks grown on AB1157 or its derivatives. It has been suggested previously that the DNA present in the p4 substitution might represent part of a cryptic prophage (Herskowitz, I., and Signer, E. R. (1974). Virology 61, 112–119). Our finding that the DNA is rescuable from many E. coli strains and that other fragments of the bacterial genome are not rescued supports this hypothesis. The absence of the cryptic fragment from AB1157 parallels the absence of other phenomena that have been attributed to a cryptic prophage, suggesting that the p4 DNA may be part of a larger cryptic fragment.
3'- and 4'-chloro-substituted analogs of benztropine: intravenous self-administration and in vitro radioligand binding studies in rhesus monkeys.

Rationale: The reinforcing effects of many psychomotor stimulants have been related to increased dopaminergic neurotransmission. Drugs that block dopamine (DA) uptake have generally been found to function as positive reinforcers. Benztropine (BZT) and several of its halogenated analogs have previously been characterized as potent DA-uptake inhibitors with behavioral profiles that indicate diminished psychomotor stimulant effects relative to cocaine. Objectives: The present experiments were designed to examine, in rhesus monkeys, the reinforcing effects of the DA-uptake inhibitor BZT and two chloro-analogs 3’-C1-BZT and 4’-Cl-BZT, and to compare self-administration and binding profiles. Methods: Four rhesus monkeys self-administered cocaine i.v. under a fixed-ratio 10 (FR10) schedule until stable responding was established. Saline, and various doses of cocaine, BZT, and the BZT analogs were then made available for self-administration. Binding of these compounds to monoaminergic and cholinergic sites in monkey brain were determined using standard radioligand binding techniques. Results: Self-administration was maintained by both 3’-C1-BZT and 4’-Cl-BZT, but not by BZT. Results suggested that 3’-C1-BZT and 4’-Cl-BZT were weak positive reinforcers. BZT and analogs bound DA transporters (DAT) with affinities higher than that of cocaine and had affinity for muscarinic binding sites. Conclusions: Surprisingly, high affinity at DATs was associated with weak or no reinforcing effects. The mechanism(s) that may underlie this dissociation between DAT actions and reinforcing effects remains to be established. These data support the proposal that a lead for the discovery of a pharmacotherapeutic agent for cocaine abuse may come from this group of compounds.
Diabetic foot infections: a team-oriented review of medical and surgical management.

As the domestic and international incidence of diabetes and metabolic syndrome continues to rise, health care providers need to continue improving management of the long-term complications of the disease. Emergency department visits and hospital admissions for diabetic foot infections are increasingly commonplace, and a like-minded multidisciplinary team approach is needed to optimize patient care. Early recognition of severe infections, medical stabilization, appropriate antibiotic selection, early surgical intervention, and strategic plans for delayed reconstruction are crucial components of managing diabetic foot infections. The authors review initial medical and surgical management and staged surgical reconstruction of diabetic foot infections in the inpatient setting. Keywords: diabetic foot; infection; antibiotics; debridement; surgery (Published: 13 September 2010) Citation: Diabetic Foot & Ankle 2010, 1 : 5438 - DOI: 10.3402/dfa.v1i0.5438
RIFLE criteria for acute kidney injury in aortic arch surgery.

Objective The RIFLE criteria are new international consensus definitions for acute kidney injury introduced to facilitate research across disciplines. We identified risk factors for acute kidney injury, renal replacement therapy, and mortality using the RIFLE criteria (RIFLE = risk, injury, failure, loss, end stage) in patients undergoing deep hypothermic circulatory arrest for aortic arch reconstruction. Methods A single-center retrospective cohort study of 267 patients undergoing aortic arch surgery with deep hypothermic circulatory arrest was conducted between July 2001 and October 2005. Known predictors (age, chronic kidney disease, surgery status, redo, diabetes, hypertension, blood transfusion, bypass, and deep hypothermic circulatory arrest time) were used in multivariate logistic regression models for acute kidney injury, renal replacement therapy, and mortality. Results Mean age was 64 years (range 23–89 years) with 166 men (62%). Seventy-five (28%) had RIFLE scores of I or F, and 22 (8%) required dialysis. Risk factors for acute kidney injury were hypertension (odds ratio [OR] = 2.17; 95% confidence intervals [CI], 1.14–4.15), chronic kidney disease (OR = 9.04; 95% CI, 1.97–41.59), packed red blood cells greater than 5 units (OR = 2.37; 95% CI, 1.20-4.69), and admission creatinine/Modification of Diet in Renal Disease predicted creatinine ratio greater than 1 (OR = 3.54; 95% CI, 1.95–6.45). Risk factors for mortality were age (per 10 years) (OR = 2.35; 95% CI, 1.35–4.06), AKI (RIFLE class R, I, or F) (OR = 4.60; 95% CI, 1.34–15.77), and cerebrovascular accident (OR = 19.1; 95% CI, 4.96–73.58). Mortality increased with each RIFLE stratification (RIFLE class 0 = 3%, R = 9%, I = 12%, and F = 38%). Conclusions Acute kidney injury as defined according to the RIFLE classification is a risk factor for mortality and will be useful in future studies of renal dysfunction in thoracic aortic surgery.
Limited liability and share transferability: An analysis of California firms, 1920–1940

Abstract In 1931, California became the last U.S. state to adopt limited liability. Prior to that, from its inception as a state in 1849, stockholders of California corporations faced pro rata unlimited liability. California's unique liability rule during 1849–1931 provides a natural experiment for testing Woodward's (1985) and Alchian and Woodward's (1987, 1988) hypothesis that limited liability reduces transaction costs and facilitates the transferability of shares. Using a small sample of publicly traded California firms and a corresponding sample of benchmark companies, we find that trading volume and share turnover were significantly lower for California firms when California had unlimited liability. After California adopted limited liability, trading volume and share turnover increased significantly for California firms relative to non-California firms. In addition, bid–ask spreads were significantly higher for California firms during the period of unlimited liability and they declined for California firms relative to non-California firms after California adopted limited liability. The results support Alchian and Woodward's hypothesis that limited liability reduces transaction costs and promotes the transferability of shares.
Establishing a Context for River Rehabilitation, North Fork Gunnison River, Colorado

Initial river rehabilitation efforts along the North Fork Gunnison River in Colorado focused on the use of in-stream structures and channel stabilization to create a single-thread channel with pools along a braided river. These efforts were based on the assumption that the river’s braided planform results primarily from land use during the past century. In order to establish a context for further rehabilitation, we evaluated the possibility that the river might be braided as a result of processes independent of land use. We estimated volume, grain-size distribution, and lithology of sediment sources along the river corridor and evaluated the planform stability of the river during the past century using historical sources, aerial photographs covering 1939–1997, and comparison of bankfull discharge and gradient in the study area to values published for braided and meandering rivers. Our results indicate that the North Fork Gunnison River has been primarily braided in its lower reaches during the past few hundred years, although the channel planform tends toward a single-thread channel during decades of lower precipitation and discharge. Although land use is not the primary cause of braiding along the North Fork Gunnison River, it has decreased channel stability, and rehabilitation efforts should be designed to reduce these effects. Our results illustrate the importance of planning river rehabilitation measures within a historical context that accounts for both catchment-scale and reach-scale controls on channel processes and planform.
Maximizing phenotype constraint and extracellular matrix production in primary human chondrocytes using arginine-glycine-aspartate concentration gradient hydrogels.

New systematic approaches are necessary to determine and optimize the chemical and mechanical scaffold properties for hyaline cartilage generation using the limited cell numbers obtained from primary human sources. Peptide functionalized hydrogels possessing continuous variations in physico-chemical properties are an efficient three-dimensional platform for studying several properties simultaneously. Herein, we describe a polyethylene glycol dimethacrylate (PEGDM) hydrogel system possessing a gradient of arginine–glycine–aspartic acid peptide (RGD) concentrations from 0 mM to 10 mM. The system is used to correlate primary human osteoarthritic chondrocyte proliferation, phenotype maintenance and extracellular matrix (ECM) production to the gradient hydrogel properties. Cell number and chondrogenic phenotype (CD14:CD90 ratios) were found to decline in regions with higher RGD concentrations, while regions with lower RGD concentrations maintained cell number and phenotype. Over three weeks of culture, hydrogel regions containing lower RGD concentrations experience an increase in ECM content compared to regions with higher RGD concentrations. Variations in actin amounts and vinculin organization were observed within the RGD concentration gradients that contribute to the differences in chondrogenic phenotype maintenance and ECM expression.
Brillouin scattering studies of the elastic properties of metallic superlattices

Abstract The determination of the elastic properties of metallic superlattices using Brillouin scattering is discussed. Previous work by our group is reviewed and preliminary results for Ag/Pd superlattices are reported.
A Chronotron for Relativistic Neutron Time-of-Flight Measurements

Neutrons in pulses produced at a 19 mc rate by the circulating beam of the 184-inch cyclotron striking an internal target have kinetic energies from 100 to 800 mev. Circulating-beam bunching limits the time duration of each neutron pulse. Reference signals are produced by a Cherenkov-radiator internal target or the radio-frequency voltage on the cyclotron dee. The chronotron coincidence circuits, capable of a resolving tine of less than 10-9 second, are spaced with increasing time intervals to reduce reflection reinforcement. Saturation of coincidence circuits minimizes the dependence on signal amplitude. The 125-? cable is matched at sampling points by a series inductance tapped by tube input capacity.
Evaluation of antigen and antibody detection in urine specimens from children with congenital human cytomegalovirus infection

Fetal infection with human cytomegalovirus (HCMV) is the leading viral cause of brain damage among newborns at birth or later in life. Efforts to screen newborns routinely for shedding of the virus by immunoassay have been hampered by inhibitors in urine, reportedly the host protein beta2-microglobulin (beta 2m). An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of HCMV antigen in which the reactivity was not affected by the presence of beta 2m, but nevertheless inhibition was observed when urine samples with high levels of virus were tested. The presence of antibodies to HCMV was demonstrated in these urine samples by antibody ELISA and immunoblot using the major antigenic protein of HCMV (pp150) expressed in Escherichia coli; this offers an alternative explanation for the inhibition in ELISA. The presence of HCMV antibodies correlated significantly with congenital HCMV infection (as detected by tissue culture isolation of virus from urine samples of newborns), especially with asymptomatic cases (sensitivity 70%; specificity 94%). The data indicate a local (renal) immune response to HCMV in congenitally infected children, which may have future diagnostic applications.
The model-theoretic ordinal analysis of theories of predicative strength

We use model-theoretic methods described in [3] to obtain ordinal analyses of a number of theories of firstand second-order arithmetic, whose proof-theoretic ordinals are less than or equal to Γ0.
A GLOBAL MODEL OF POPULATION-RESOURCE INTERACTION

. A global model of population-resource interaction is proposed consisting of two first order ordinary differential equations. In it the population growth rate increases due to increasing technology, then declines due to declining resources. When the model is fit to twentieth century data it predicts that global population will peak and then decline while already declining global resources bottom out; both will eventually stabilize slightly above their lows. Because of the uncertainty of model parameters and resource data, the values and times of these peaks and lows are uncertain, but the qualitative behavior of the model transcends this uncertainty. Actual best-fit values of population include a peak of nearly nine billion about year 2050 and a peak rate of decline of 0.3% about year 2100. Global resources bottom out at 70% of optimum around year 2100. Variability and sensitivity analyses are also provided.
Evaluation of the residual lifetime of a section of a main gas pipeline after long-term operation

The soil environment of an emergency section of a main gas pipeline is characterized as “near-neutral” (pH < 8) with middle or, in some cases, even high (more than 0.3 mm/year) corrosion activity and can be modeled by the NS4 solution. Long-term operation (23 years) decreases mainly the static crack resistance of X60 and X70 steels, whereas hydrogenation under the potential of cathodic protection sharply increases their susceptibility to stress corrosion fracture under both static and cyclic loading. The X70 steel is more sensitive to the negative influence of operation and hydrogenation as compared with X60 steel. We have evaluated the residual lifetime of the section of the “Urengoi–Pomary–Uzhgorod” main gas pipeline with regard for hydrogenation of the pipeline wall.
Private Higher Educational Institutions in a changing South African environment

One of the problems experienced by potential learners is accessibility to education facilities, especially in rural areas and for people with time constraints. The objective of this research is to investigate the role for Private Higher Educational Institutions (PHEIs) in South Africa, sharing the task of providing education with government supported institutions. Although distance learning is not a panacea for all educational problems, it holds great promise for driving change in education. The research is based on questionnaires, interviews and literature. Results indicated that traditional residential education couldn't reach all people. Distance learning can relieve the situation. However, both private and public providers of higher education (residential and distance) can co-exist in South Africa. Private Higher Distance Learning (PHDL) contributes in lowering present levels of unemployment by providing skills, as many prospective students stay in rural areas and townships. This paper emphasizes some of the changes impacting on the future of PHDL and bringing education opportunities to masses by creating an environment of shared responsibility between government institutions and private initiatives, jointly servicing a greater part of the population.
An improved enzyme-linked immunoassay for the detection and quantification of the entomocidal parasporal crystal proteins of Bacillus thuringiensis subspp. kurstaki and israelensis

An improved and simplified enzyme-linked immunosorbent assay (ELISA) was developed for the detection and quantification of parasporal crystalline toxins from Bacillus thuringiensis subsp. kurstaki. The improved procedure involved pretreatment of the polystyrene cuvettes with glutaraldehyde before antibody coating. A direct comparison of treated and untreated cuvettes is provided. ELISAs were then used for the analysis of the entomocidal crystalline proteins in commercial and experimental formulations of B. thuringiensis subspp. kurstaki and israelensis.
Islets of Langerhans: dye coupling among immunocytochemically distinct cell types

Cells in isolated rat islets of Langerhans were microinjected with Lucifer Yellow CH in a medium containing 16.7 millimolar glucose. Dye was rapidly transferred from the injected cell to neighboring islet cells without specificity with regard to the immunocytochemical identity of either the donor or the recipient cells. The transfer of dye between the islet cells (types A, B, and D) demonstrates homologous and heterologous cell coupling in a system where the normal proportions and relationships of the cell types are maintained.
B16/F10 tumors in aged 3D collagen in vitro simulate tumor growth and gene expression in aged mice in vivo.

Although the incidence of cancer rises with age, tumor growth is often slowed in older hosts. The B16/F10 melanoma cell line is commonly used in murine models of age-related tumor growth suppression. We wished to determine if the growth pattern and gene expression of B16/10 tumors grown in aged mice could be simulated in 3D collagen matrices derived from aged mice. Outcome measures were tumor size in vitro and gene expression of the key growth regulatory molecules: growth hormone receptor (GHR), IL-10Rβ, IL-4Rα, and IL-6. B16/F10 tumors were grown in 20–25-mo-old C57/BL6 male mice. Tumor sizes ranged from 30 to 4,910 mg in vivo. Tumors from a subset of mice were removed after euthanasia, and equivalent amounts of each tumor were placed in aged 3D collagen and grown for 5 d. Tumor sizes in aged 3D collagen correlated highly with their original tumor size in vivo. Gene expression changes noted in vivo were also maintained during tumor growth in aged 3D collagen in vitro. The relative expression of GHR was increased, IL-10Rβ was unchanged, and IL-4Rα and IL-6 were decreased in the larger tumors relative to the smaller tumors in vitro, in a pattern similar to that noted in vivo. We propose that 3D matrices from aged mice provide an in vitro model of tumor growth that correlates highly with tumor size and expression of key regulatory molecules in vivo.
TEACHING RESOURCEFULNESS SKILLS TO OLDER ADULTS

With rapidly increasing numbers of elders in the United States, there is a growing need for interventions to promote independence and productive, healthy lifestyles among the elderly. Highly resourceful persons have been found to function better in their daily activities than those who lack resourcefulness skills. These skills, including self-controlling techniques and problem-solving, are believed to be learned and therefore can be taught. This pilot study examined the effects of teaching resourcefulness skills to healthy elders on measures of learned resourcefulness, anxiety, depression, adaptive functioning, and life satisfaction using a quasi-experimental pre-test-post-test design. The intervention group consisted of 20 elders and the placebo group had 17 elders. Those elders who received the 6-week small group intervention that taught the skills constituting resourcefulness scored significantly higher on post-test measures of learned resourcefulness, adaptive functioning, and life satisfaction. Although significant negative correlations were found between resourcefulness scores and scores on measures of anxiety and depression, there were no significant differences in anxiety and depression between the intervention and placebo groups on the post-test measures. The findings suggest that learned resourcefulness training (LRT) is an important nursing intervention for promoting healthy, independent, and productive lifestyles among older adults.
Modeling and Computer Simulation of the Compressional Behavior of Fiber Assemblies: Part I: Comparison to van Wyk's Theory

A model is presented that allows prediction of the properties of a fiber assembly under compression from the physical properties of its component fibers, taking into account both static and kinetic...
Brain-pituitary-gonadal axis during early development and sexual differentiation in the rainbow trout, Oncorhynchus mykiss.

Abstract Profiles of testosterone, 11-ketotestosterone, androstenedione, and estradiol were determined by RIA, and immunocytochemical techniques were employed to identify gonadotropin (GTH) I and II and gonadotropin releasing hormone (GnRH) in monosex and mixed sex populations of rainbow trout from 1 to 126 days postfertilization (dpf). Steroid levels were relatively high at 1 dpf and declined until 25 dpf. At 30 and 48 dpf (hatching) steroid levels increased slightly before they fell by 78 dpf and remained relatively constant thereafter. Trends toward differences in steroid content between males and females became evident around the time gonadal differentiation was histologically discernible (78 and 90 dpf). GTH I was present in the proximal pars distalis at all dates (48–126 dpf), whereas GTH II was not detectable. GnRH was found at all dates (48–126 dpf) and was distributed in several areas of the brain including the nucleus preopticus periventricularis, nucleus lateralis tuberis, and the pituitary in the region where GTH I was found. No differences were seen between males and females in the timing of appearance, localization, or intensity of staining of these peptide hormones. Given that the brain–pituitary–gonadal axis seems to be intact during the process of sexual differentiation and the fluctuations of steroid levels during this process, sex steroids may play the driving role for sexual differentiation of rainbow trout.
Clinical comparison of conventional and rare earth screen-film systems for cephalometric radiographs

This study compared cephalometric and P-A skull films taken with conventional (CaWO4) screens and rare earth screens. Patient exposure was reduced by 17 to 55 percent on two different x-ray machines by the use of rare earth screens. Results from 130 clinical evaluations showed that the diagnostic quality of radiographs taken with either system was roughly comparable. This presents a persuasive argument for the use of rare earth screens since the diagnostic quality of the films can be maintained while significantly reducing the patient's exposure to radiation.
The absolute configurations of organometallic compounds. XX. The conformations and absolute configurations of four preferred and non-preferred diastereoisomers having composition (R″-C5H4)Mo(CO)2[(HCPhR)N(CPh)N(HCPhR′)]

Abstract The structures and absolute configurations of four optically resolved compounds having composition (R″-C5H4)Mo(CO)2[(HCPhR)N(HCPh-R′)] were established by X-ray diffraction methods. Benz I [R″ = R′ = H, R = −CH3]: triclinic, space group P1; a = 9.792(3), b = 11. 875(4), c = 11.885(3) A, α = 88.27(2), β = 67.42(2) and γ = 83.71°. Cell volume = 1268.21 A3, Z = 2 molecules/unit cell. Benz II [R″ = R′ = H, R = −CH3]: orthorhombic, space group P212121; a = 9.885(3), b = 11.550(5), c = 22.620(9) A Cell volume = 2623.67 A3, Z = 4 molecules/unit cell. Benz I and II are of identical composition and differ only in conformation at the (−CH(CH3)Ph) substituent of the benzamidine ligand, the former being the thermodynamically preffered stereoisomer. Benz III differs from Benz I and Benz II in that both nitrogens of the benzamidine ligand bear optically active substituents of composition (−CH(CH3)Ph); therefor R″ = H and R′ = R = −Ch3. The substance crystallizes in the space group P212121 with a = 9.656(2), b = 11.691(7) and c= 23.562(6) A. Cell volume = 2660.08 A3 and Z =4 molecules/unit cell. Like Benz II, this is also a non-preferred stereoisomer. Finally, Benz IV, like Benz III, has optically active substituents at both benzamidine ligand nitrogens, but also bears a methyl substituent at Cp; i.e., R″ = R′ = R = CH3. Orthorhombic, P212121; a= 9.737(7), b = 11.716(4) and c = 23.661(9) A. Cell volume = 2698.96 A3, Z = 4 molecules/unit cell. This is also a non-preferred stereoisomer. For the convenience of the reader, all of this terminology is reviewed in the Introduction. The two independent molecules in the asymmetric unit of Benz I (Benz Ia and Benz Ib) have essentially identical bond lengths and angels and slightly different inter-planar angels associated with the phenyl rings, which have large areas over which packing forces can exert substantial torsional pressures. Benz II, III and IV also have few differences among themselves or with Benz Ia and Benz Ib insofar as bond lengths and angels are concerned, but differ somewhat in their interplanar angels in the same manner described for Benz I. Details of conformational and configurational problems in this series are given in the text.
Limits of quasi-static solutions in impact of composite structures

Abstract Transverse impact is an important service condition for composite structures because of the potential for material damage. A problem that often arises in the study of transverse impact is whether a quasi-static analysis if sufficient, or whether a dynamic solution is required. A rule is developed that is intended to provide a convenient method of classifying impact problems in this regard. The rule is based on the calculation of an equivalent structure mass that can be considered to be lumped at the impact site, and then uses the ratio of impact mass to equivalent lumped structure mass to establish the limits of applicability of the quasi-static solution procedure. This rule is closely related to others based on natural frequencies, but only requires knowledge of the static deformation response. Comparisons with dynamic calculations demonstrate the general applicability of this rule for the impact response of composite plates and cylinders.