cssi/SciSciGPT-SciSciNet huggingface dataset:
Nurse Specialization in Reproductive Endocrinology

The nursing role in reproductive endocrinology, including administrative, clinical and research responsibilities in several clinical settings, is discussed. Within the framework presented, the nurse can provide care to patients with a variety of reproductive disorders, such as infertility and amenorrhea. The coordination of care offers nurses an excellent opportunity to assist in the development of coping methods to help the patient deal with life stresses.
Vitamin D modulates the effects of follicle-stimulating hormone of sertoli cell function and testicular growth in siberian hamsters

Sertoli cells from immature (18–20 day old) Siberian hamsters (Phodopus sungorus) raised in a long photoperiod (LD; 16hL : 8hD) or a short photoperiod (SD; 6hL : 18hD) were cultured and exposed to follicle-stimulating hormone (FSH) and/or vitamin D3 (D3) in vitro. D3 did not stimulate lactate production when added alone, but significantly augmented the stimulatory action of FSH on lactate production by Sertoli cells from both LD- and SD-exposed hamsters. Hamsters raised in LD or SD were injected daily with D3 for 10 days starting at 18 days of age. This treatment resulted in a significant increase in the testicular weight of hamsters raised in LD in which circulating FSH levels are high. In contrast, testicular weight was not altered by D3 treatment in SD hamsters in which circulating levels of FSH are low. We conclude that D3, probably after hydroxylation to 1,25(OH)2 vitamin D3, modulates the action of FSH on testicular growth and Sertoli cell function.
Dissociable crossmodal recruitment of visual and auditory cortex for tactile perception

Primary sensory areas previously thought to be devoted to a single modality can exhibit multisensory responses. Some have interpreted these responses as evidence for crossmodal recruitment (i.e., primary sensory processing for inputs in a non-primary modality); however, the direct contribution of this activity to perception is unclear. We tested the specific contributions of visual and auditory cortex to tactile perception in healthy adult volunteers using anodal transcranial direct current stimulation (tDCS). This form of non-invasive neuromodulation can enhance neural excitability and facilitate learning. In a series of psychophysical experiments we characterized participants’ ability to discriminate grating orientation or vibration frequency. We measured perceptual sensitivity before, during, and after tDCS application over either visual cortex or auditory cortex. Each participant received both anodal and sham interventions on separate sessions in counterbalanced order. We found that anodal stimulation over visual cortex selectively improved tactile spatial acuity, but not frequency sensitivity. Conversely, anodal stimulation over auditory cortex selectively improved tactile frequency sensitivity, but not spatial acuity. Furthermore, we found that improvements in tactile perception persisted after cessation of tDCS. These results reveal a clear double-dissociation in the crossmodal contributions of visual and auditory cortex to tactile perception, and support a supramodal brain organization scheme in which visual and auditory cortex comprise distributed networks that support shape and frequency perception, independent of sensory input modality.
Effects of aging on rheological and proteolytic properties of goat milk Jack Cheese produced according to cow milk procedures

Abstract Pasteurized milk from French Alpine goats was processed into Jack Cheese according to modified processing conditions used for manufacturing Monterey Cheese from bovine milk. The effect of time on proteolytic and rheological changes that occurred on this cheese during aging was investigated. Commercial mesophilic culture, Lactococcus lactis subsp. lactis , was added to milk at the rate of 16 ml/100 l. The percentages of moisture, salt, protein, and fat in this cheese were 46.43, 1.19, 22.38, and 27.4, respectively. The salt to moisture ratio was 2.56. This cheese was vacuum-packed and stored at 4–5 °C for 30 weeks and the rheological and proteolytic properties were determined. The force required to compress the cheese to 20% of its original height during the first cycle increased during aging. However, the force required to compress the cheese to 75% of its original height during the first cycle did not change during aging. Similar trends were found during the second compression cycle. Elasticity values at 20% compression increased during aging; however, at 75% compression they did not change. Electrophoretic analysis of the caseins in the goat milk Jack Cheese revealed that beta casein was the most abundant casein and was less susceptible to proteolysis than other caseins. The alpha and kappa caseins were the second and the third major caseins in goat Jack Cheese, respectively. Similar to bovine gamma caseins, as beta casein was hydrolyzed in this cheese it gave rise to gamma caseins. The modified manufacturing conditions and elucidation of the chemical and physical properties of this goat milk cheese are not only providing scientific information for further research but also furnishing valuable information for practical application in production of goat milk Jack Cheese.
Macular pigment optical density in a Southwestern sample.

PURPOSE Increasing evidence implicates macular pigment in protecting the retina and retinal pigment epithelium from light-initiated oxidative damage. Little information, however, is available regarding "average" levels of macular pigment in the general population. This study was designed to assess macular pigment in a high-light environment and to determine what personal characteristics influence macular pigment density in that sample. METHODS Macular pigment optical density was measured psychophysically using a 1 degree, 460-nm test stimulus. Personal data were collected using a questionnaire. RESULTS 217 subjects (79 men, 138 women) were recruited from the Phoenix metropolitan area (age range = 17-92 years). The average macular pigment density was 0.22 +/- 0.13. There was a slight tendency for macular pigment density in this sample to decline with age (r = -0.14, P < 0.02). Average macular pigment density was significantly lower in women versus men (P < 0.05), lower in individuals with light-colored irises versus dark-colored irises (P < 0.009), and lower in heavy smokers compared to light (P < 0.0045) and never (P < 0.034) smokers. CONCLUSIONS Macular pigment density was lower than average levels obtained from the Northeast but similar to average values obtained in a recent study of adults recruited from Indianapolis. Consistent with past studies, MP density was 13% lower in women and 18% lower in individuals with light- versus dark-colored irises. The relation of smoking to macular pigment density was only significant for those current smokers who smoked more than 10 cigarettes per day (about a 25% reduction). The large number of individuals in this sample with low macular pigment density motivates the need for population-based assessment of the possibly poor nutritional state of the average American's retina.
Synoptic-Scale and Mesoscale Environments Conducive to Forest Fires during the October 2003 Extreme Fire Event in Southern California

This study has employed both observational data and numerical simulation results to diagnose the synoptic-scale and mesoscale environments conducive to forest fires during the October 2003 extreme fire event in southern California. A three-stage process is proposed to illustrate the coupling of the synoptic-scale forcing that is evident from the observations, specifically the high pressure ridge and the upper-level jet streak, which leads to meso-α-scale subsidence in its exit region, and the mesoscale forcing that is simulated by the numerical model, specifically the wave breaking and turbulence as well as the wave-induced critical level, which leads to severe downslope (Santa Ana) winds. Two surges of dry air were found to reach the surface in southern California as revealed in the numerical simulation. The first dry air surge arrived as a result of moisture divergence and isallobaric adjustments behind a surface cold front. The second dry air surge reached southern California as the meso-α- to meso-β-scale subsidence and the wave-induced critical level over the coastal ranges phased to transport the dry air from the upper-level jet streak exit region toward the surface and mix the dry air down to the planetary boundary layer on the lee side of the coastal ranges in southern California. The wave-breaking region on the lee side acted as an internal boundary to reflect the mountain wave energy back to the ground and created severe downslope winds through partial resonance with the upward-propagating mountain waves.
Studies on the tardigrades. IV. Fine structure of the hindgut of Milnesium tardigradum doyère.

The hindgut of the semi-terrestrial tardigrade, Milnesium tardigradum was examined with light and electron microscopy. The hindgut consists of a cloaca and an anterior hindgut. It is delineated anteriorly by the pylorus into which four Malpighian tubules empty and posteriorly, by a broad cloacal slit. A single oviduct enters the hindgut at the junction between the cloaca and the anterior hindgut. Two pairs of muscles insert on the cloaca and anterior hindgut respectively. Electron microscopic observations demonstrate that the anterior hindgut is a specialized transporting epithelium. The luminal surface is covered by a thin layer of cuticle which penetrates into channel-like invaginations. Numerous mitochondria are concentrated apically. The basal and lateral surfaces are also folded. The cells are joined apically by deep tight junctions and a simple basal lamina lines the entire hindgut. The cloaca which receives the contents of the gut and Malpighian tubules as well as gametes of the reproductive tract is a transitional organ that exhibits several characteristics of the hypodermis and anterior hindgut. The cuticle of the cloaca changes sequentially from the complex structure of the integument to a simple layer of the anterior hindgut. The function of the hindgut is discussed with emphasis on the possible response of the anterior hindgut to a hypoosmotic habitat, evaporative water loss during the induction of anhydrobiosis and low oxygen tension.
Segregation of heterokaryons in the asexual cycle of Phycomyces

Artificial heterokaryons between carotene mutants ofPhycomyces blakesleeanusBgff. have been prepared by squeezing cytoplasm out of two different mutant sporangiophores and allowing the fused droplets to regenerate.
Haemodilution in an eight-month-old infant

Summary Transient haemodilution was carried out in an 8-month-old infant whose parents were Jehovah's Witnesses during an abdominoperineal pull-through procedure. Adult ACD blood packs were altered to suit the needs of the child. With judicious fluid management, the child was extubated and did well postoperatively.
Does erythrocyte infusion improve 3.2-km run performance at high altitude?

The effects of autologous erythrocyte infusion on improving exercise performance at high altitude have not previously been studied. The effects of erythrocyte infusion on 3.2-km (2-mile) run performance were evaluated during 3 days (HA3) and 14 days (HA14) exposure to high altitude (4300 m) in erythrocyte-infused (ER) and control (CON) subjects that were initially matched (P > 0.05; n = 8 in each group) for age, body size and aerobic fitness. After sea-level runs (SL; 50 m), unacclimated-male subjects received either 700 ml of saline and autologous erythrocytes (42% hematocrit; ER) or saline alone (CON). The 3.2-km run times (min:s) did not differ (P > 0.05) between groups at SL [mean (SEM) ER, 13:14 (00:19); CON, 13:39 (00:32)] or during HA3 [ER, 19:02 (00:18); CON, 19:44 (00:43)] and HA14 [ER, 17:44 (00:27); CON, 18:45 (00:55)] but times were slower (P 0.05) for ER compared to CON. Thus, no significant improvements in 3.2-km run performance were associated with erythrocyte infusion, although the ER group showed a tendency to run slightly faster at high altitude.
Immunocytochemical localization of serotonin in the brain and pituitary gland of the platyfish, Xiphophorus maculatus.

Immunoreactive serotonin (ir-5HT) containing cells were localized in the brain and pituitary gland of the platyfish by use of immunoperoxidase procedures. In the brain, ir-neurons were found lining the wall of the third ventricle and in its lateral and posterior recesses. More caudally, ir-perikarya were found in the valvular portion of the cerebellum and in the raphe region. Ir-5HT was also localized within the pineal gland in fish that had been sacrificed before 1:00 p.m. Within the pituitary gland, ir-5HT was localized in periodic acid Schiff-positive cells of the pars intermedia of all fish while, in only a few animals, less intense immunoreactivity was also present in gonadotrops of the caudal pars distalis.
Effects of septal lesions on passive avoidance behavior using ice water as the aversive stimulus.

Abstract Passive avoidance behavior following septal lesions was studied using an aversive stimulus which consisted of dropping the rat into ice water. In contrast to the inferior passive avoidance acquisition and retention when electric shock is used as the aversive stimulus, in the present study rats with septal lesions displayed superior retention of the passive avoidance response.
Violence and today's youth

The violent behavior of adolescents in our society is a topic of enormous interest and concern, limited data and knowledge, and, unfortunately, substantial misinformation and distortion. In 1990, some 16.3% (1,749,343) of the total number of arrests in the United States were of youth 17 years of age or younger, and 5.5% (95,677) of these arrests were for violent crimes. Of incarcerated youth (fewer than 100,000 of all prisoners), about one quarter have committed crimes against persons. Although the overall magnitude of this problem is often distorted by the media, these numbers, which have increased over the past decade, do mask the substantially higher rates in extremely poor, populous urban communities. In addition, on a national survey, about 20% of adolescents reported having engaged in one violent incident by 18 years of age. Other youths are the predominant victims of violent behavior by adolescents, Many environmental, psychologic, and biologic risk and protective factors and population indicators have been related to violent behavior and, in various combinations, increase or decrease the likelihood of its occurrence. However, no one theory or combination of variables allows prediction of which individuals will commit violent acts or what interventions will prevent these acts initially or reduce the incidence of repeated offenses. Few, if any, of the individual therapeutic techniques, promising state or community-based programs, or traditional law enforcement and judicial approaches have been adequately evaluated to determine whether they are effective in reducing violent incidents in schools and neighborhoods. The juvenile courts have become increasingly punitive, more youths are being transferred to adult criminal courts, and increasing numbers of adolescents are being incarcerated at a national average cost of about $35,000 per youth per year. Nevertheless, despite our lack of certainty about what will work to decrease violence among youth, we do know enough to take a number of practical steps that are likely to ameliorate the situation. These include a combination of activities directed toward improving the quality of life in areas of extreme poverty in large cities, and reforming the juvenile justice system. — R.E.B.
Pharmacokinetics and Safety of Cefamandole in Newborn Infants

Cefamandole, a new parenteral cephalosporin antibiotic, was administered to 23 newborn infants with pustular skin infection due to Staphylococcus aureus for an average duration of 7.5 days. All the patients improved clinically. Elevation of serum glutamic oxaloacetic transaminase and eosinophilia were observed in nine infants each transiently during treatment. There were no abnormalities of renal functions and Coombs' test results remained negative. The levels of cefamandole in serum after either intravenous or intramuscular administration were higher and the mean life was longer than those previously reported in older infants, children, and adults.
Disease-associated casein kinase I δ mutation may promote adenomatous polyps formation via a Wnt/β-catenin independent mechanism

The Wnt signaling pathway is critical for embryonic development and is dysregulated in multiple cancers. Two closely related isoforms of casein kinase I (CKIδ and ϵ) are positive regulators of this pathway. We speculated that mutations in the autoinhibitory domain of CKIδ/ϵ might upregulate CKIδ/ϵ activity and hence Wnt signaling and increase the risk of adenomatous polyps and colon cancer. Exons encoding the CKIϵ and CKIδ regulatory domains were sequenced from DNA obtained from individuals with adenomatous polyps and a family history of colon cancer unaffected by familial adenomatous polyposis or hereditary nonpolyposis colorectal cancer (HNPCC). A CKIδ missense mutation, changing a highly conserved residue, Arg324, to His (R324H), was found in an individual with large and multiple polyps diagnosed at a relatively young age. Two findings indicate that this mutation is biologically active. First, ectopic ventral expression of CKIδ(R324H) in Xenopus embryos results in secondary axis formation with an additional distinctive phenotype (altered morphological movements) similar to that seen with unregulated CKIϵ. Second, CKIδ(R324H) is more potent than wildtype CKIδ in transformation of RKO colon cancer cells. Although the R324H mutation does not significantly change CKIδ kinase activity in an in vitro kinase assay or Wnt/β-catenin signal transduction as assessed by a β-catenin reporter assay, it alters morphogenetic movements via a β-catenin-independent mechanism in early Xenopus development. This novel human CKIδ mutation may alter the physiological role and enhance the transforming ability of CKIδ through a Wnt/β-catenin independent mechanism and thereby influence colonic adenoma development. © 2006 Wiley-Liss, Inc.
The thermal decomposition of water

The reflected shock tube technique with multipass absorption spectrometric detection of OH-radicals at 308 nm, corresponding to a total path length of 1.749 m, has been used to study the reaction H2O + M → H + OH + M between 2196 and 2792 K using 0.3, 0.5, and 1% H2O, diluted in Kr. As a result of the increased sensitivity for OH-radical detection, the existing database for this reaction could be extended downward by ∼500 K. Combining the present work with that of Homer and Hurle, the composite rate expression for water dissociation in either Ar or Kr bath gas is k1,Ar(or Kr) = (2.43 ± 0.57) × 10−10 exp(−47117 ± 633 K/T) cm3 molecule−1 s−1 over the T-range of 2196–3290 K. Applying the Troe factorization method to data for both forward and reverse reactions, the rate behavior could be expressed to within <±18% over the T-range, 300–3400 K, by the three-parameter expression k1,Ar = 1.007 × 104T−3.322 exp(−60782 K/T) cm3 molecule−1 s−1 A large enhancement due to H2O with H2O collisional activation has been noted previously, and both absolute and relative data have been considered allowing us to suggest k1, H2 O = 1.671 × 102T−2.440 exp(−60475 K/T) cm3 molecule−1 s−1 for the rate constants with H2O bath gas over the T-range, 300–3400 K. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 211–219, 2006
WHO IS SICK

The definition of a case which states that “everybody is sick” is a deterrent to progress in psychiatry. It reduces the urgency for diagnostic classification and etiologic search. Worst of all, it rationalizes a pattern whereby the healthiest patients receive the greatest amount of active treatment and the sickest the least.
Ro/SS-A and the pathogenic significance of its antibodies.

Ro/SS-A is a soluble cellular protein to which antibodies are frequently directed in patients with Sjogren's syndrome (SS) and systemic lupus erythematosus (SLE)-related disorders. The pathogenic significance of these antibodies is uncertain. Our effort to further characterize the immunological and structural nature of Ro/SS-A suggests that the native human Ro/SS-A molecule is not glycosylated and consists of two disulfide linked domains. The amino terminus of the smaller domain contains a major epitope reactive with anti-Ro/SS-A sera. We have isolated and characterized a complementary DNA (cDNA) clone which encodes the Ro/SS-A polypeptide. The Ro/SS-A gene does not appear to be highly polymorphic and exists as a single copy on the short arm of chromosome 19. The isolation of the Ro/SS-A cDNA should allow for a more complete characterization of Ro/SS-A epitopes which should help further elucidate the importance of Ro/SS-A antibodies in the pathogenesis of disease.
Measurement of intracellular collagen degradation

Abstract Intracellular degradation of newly synthesized collagen is quantitated by incubating fibroblasts with [14C]proline and determining the percentage of total [14C]hydroxyproline that is present in a low molecular weight fraction. Several problems make this difficult. (1) Commercial [14C]proline is often contaminated with [14C]hydroxyproline and must be purified before use. (2) Salt and [14C]proline interfere with the determination of [14C]hydroxyproline in the low molecular weight fraction and must be removed by preparative ion-exchange chromatography. (3) Epimerization of trans- to cis-hydroxyproline during acid hydrolysis is variable and must be taken into account. (4) Loss of [14C]hydroxyproline during processing varies; [3H]hydroxyproline can be used as an internal measure of recovery, even though tritium may be lost during hydrolysis. An analytic cation-exchange resin is used for the final quantitation of [14C]hydroxyproline in the low and high molecular weight fractions. With these methods, degradation of newly synthesized collagen can be determined with a precision of ± 3%.
Gas Drag and the Orbital Evolution of a Captured Triton

Abstract Gas drag is a possible mechanism for capturing Triton. We examine the energetics of gas drag capture, compare the role of gas drag in subsequent orbital evolution with that of tides, and evaluate whether a Triton captured by gas drag could have avoided spiraling into Neptune. On its own, gas drag causes the inclination of an orbit to become more prograde, and Triton's retrograde status potentially places an upper limit on the orbital energy lost due to gas drag and hence a lower limit on the amount of tidal evolution and concomitant heating. A putative Neptune nebula is modeled after a minimum mass Uranus nebula and is assumed to be isothermal and cool. Triton's initial apocenter is set at the radius of Neptune's Hill sphere and its initial pericenter within the radial range of the nebula. Despite strong evolution of both semimajor axis and eccentricity, Triton's inclination only changes by a few degrees due to gas drag, when uncoupled to inclination variations due to solar-torque-induced precession. Results are insensitive to variations in radial surface density distribution or temperature, for fixed nebular mass. Thus, Triton could have evolved to its present retrograde circular orbit by gas drag alone, and massive tidal heating is not an inevitable consequence of capture. Nontrivial tidal heating is still likely, though, because Triton's post-gas-drag eccentricity, i.e., that remaining when Triton's present-day angular momentum was reached, is likely to have exceeded ∼0.2. Despite Triton's mass, single-pass capture is shown to be energetically favorable for our nominal nebula. Capture is also energetically possible for (i) nebulae that are less massive by an order of magnitude, if Triton's heliocentric orbit was energetically close to a temporary gravitational capture, and (ii) the solar gas flowing into Neptune's accretion sphere at an earlier stage of formation. Survival of Triton against gas drag in the last case is unlikely, but the low-mass case may apply to the compact H- and He-depleted nebulae that form around planets such as Uranus and Neptune in various accretion scenarios. Once captured, evolution is rapid in the absence of solar perturbations, with the orbital angular momentum reduced to Triton's present value in under 103 years for the case of the nominal nebula. Solar tides, however, cause Triton's orbit to oscillate in and out of the protasatellite nebula and can extend the gas drag time scale, for certain initial conditions, to ∼104-105 years. Therefore Triton could have survived a short-lived (∼103 years), hot, turbulent nebula that may have formed by a giant impact with Neptune. It might have also survived a cooler, less turbulent, but longer-lived (∼106 years) low-mass nebula: the mass and angular momentum of Triton and that of a low-mass (Hand He-depleted) nebula are comparable, so orbital evolution for such a capture may "self-terminate." In particular, Triton may clear an annular region in the nebula after multiple passes through it, and for sufficiently slow radial redistribution of nebular mass, cease evolving by gas drag entirely.
Health Care Expenditures for Children with Autism Spectrum Disorders in Medicaid.

Objective To study trends in health care expenditures associated with autism spectrum disorders (ASDs) in state Medicaid programs. Method Using Medicaid data from 42 states from 2000 to 2003, patients aged 17 years and under who were continuously enrolled in fee-for-service Medicaid were studied. Patients with claims related to autistic disorder (autism) were identified, as were patients with claims for any ASD other than autism. Total expenditures per treated patient consisted of Medicaid reimbursements from inpatient, outpatient, and long-term care and prescription drugs. Inflation-adjusted expenditures were compared over time and with expenditures associated with other mental health disorders. Results A total of 2,184,677 children were diagnosed with some type of mental disorder during the study period. Of these children, 69,542 had an ASD, with 49,921 having autism and the rest having another ASD. Mean total health care expenditures per child with ASD were $22,079 in 2000 (in 2003 US dollars), and rose by 3.1% to $22,772 in 2003. The treated prevalence of autism per 10,000 covered lives rose by 32.2% from 40.6 to 53.6, the highest rate of increase among all mental disorders. Total health care expenditures for ASDs per 10,000 covered lives grew by 32.8% from $1,270,435 in 2000 (in 2003 dollars) to $1,686,938 in 2003. Conclusions Medicaid-reimbursed health care expenditures for ASD were quite substantial. Although the per patient expenditures grew slightly over time, the large increase in treated prevalence caused a considerable rise in total ASD-associated health care expenditures.
Ground-water models for water resource planning

In the past decade hydrogeologists have emphasized the development of computer-based mathematical models to aid in the understanding of flow, the transport of solutes, transport of heat, and deformation in the ground-water system. These models have been used to provide information and predictions for water managers. Too frequently, ground-water was neglected in water resource planning because managers believed that it could not be adequately evaluated in terms of availability, quality, and effect of development on surface-water supplies. Now, however, with newly developed digital ground-water models, effects of development can be predicted. Such models have been used to predict hydrologic and quality changes under different stresses. These models have grown in complexity over the last ten years from simple one-layer models to three-dimensional simulations of ground-water flow, which may include solute transport, heat transport, effects of land subsidence, and encroachment of saltwater. Case histories illustrate how predictive ground-water models have provided the information needed for the sound planning and management of water resources in the USA.
Sexually transmitted diseases, HIV, and AIDS in women

Several key points are addressed in this article including the following: 1. Most women with HIV are of reproductive age (20 to 44 years of age), acquire their HIV infection through heterosexual contact, and are women of color (African American or Latina). 2. Sex does not seem to alter substantially the presentation or natural history of HIV with the exception of unique gynecologic manifestations. 3. Women with HIV are more likely to have disease caused by HPV (such as abnormal Pap smears or warts), more severe Candida vulvovaginitis, and PID. 4. HIV is transmitted by sexual contact, exposure to infected blood or tissues, and breast-feeding. The risk of perinatal transmission has dramatically dropped to 1% to 2% with the advent of potent ARV therapy. 5. Several potent ARV therapies are now available and have greatly prolonged and enhanced the quality of life among persons with HIV. 6. New approaches to prevention of HIV transmission include use of topical microbicides, vaccines, and use of potent ARV therapies following exposure to HIV.
Approaches to organizational communication structure

Abstract The construct of organizational communication structure is defined by its 5 main dimensions: relationships, entities, contexts, configuration, and temporal stability. Four major approaches to organizational communication structure are reviewed: formal, network analysis, communication gradients, and cultural, in the light of this definition of the construct, particularly focusing on which of the 5 dimensions they emphasize. The essay concludes with several observations about the relative merits of these various approaches for examining organizational communication structure.
Efficiency of DRL responding as a function of response effort

The present study examined the relationship between DRL efficiency and response effort. One group of pigeons was required to emit a keypeck of at least 45 g force to operate the response key, while a second group had to respond with a minimum force of 15 g. Results indicated that the 45-g Ss were significantly more efficient than the 15-g Ss, although this finding was not due to the former Ss’ ability to inhibit responding.
A taxonomy for marketing: Distinctions between exchange and non-exchange, and governance adaptations and need satisfying behaviors

The idea of value passing between and among parties for the purpose of achieving one’s own goals is at the heart of marketing’s management function. This is the core of the discipline. It is important, however, for the marketer to understand the alternatives to marketing exchange, so that we know when marketing might be appropriate and when our needs might be better addressed through non-marketing behaviors. Further, we need to have a better understanding of how one might displace some forms of behavior (e.g., coercive behaviors) with exchange. This is of grave importance today in some Eastern European countries emerging from the he USSR.
Platelet activation by healing EPTFE grafts

The purpose of this study was to examine the effect of the in vivo maturing ePTFE graft surface on platelet activation. Ten canines were randomized to receive either a carotid to infrarenal aorta ePTFE graft or sham operation. Animals were sampled at specific time points up to 3 months post-operatively. Whole blood platelet aggregometry (arachidonic acid, ADP, and collagen agonists) and ATP secretion (in response to arachidonic acid, ADP, collagen, and thrombin) were measured. Additionally, complete hematologic analysis and histology were performed. With time, graft animals showed significantly more decrease in platelet aggregation in response to ADP compared to sham animals (P = .023). The total amount of ATP per platelet was not different, as demonstrated by equivalent ATP release per platelet in response to thrombin. Over the first week, grafted dogs developed a decrease in systemic platelet count of 50% (P < .001) that persisted over the 3-month follow-up period. With time, overall regression model slopes of graft and sham platelet count data were not statistically different (P = .29). Histologically, the grafts demonstrated limited cellular ingrowth at both anstomoses, with fibrin matrix along the remainder of the blood-biomaterial interface. These data suggest that, similar to Dacron, exposure to an ePTFE surface results in significant changes in platelet biology, and these platelet–ePTFE interactions persist even after the graft has formed a mature pseudointima. The pseudointima appears to be the primary determinant of the blood–biomaterial interaction. © 1995 John Wiley & Sons, Inc.
Five Elements for Effective Evaluation of Stream Restoration

River and stream restoration projects are increasingly numerous but rarely subjected to systematic post-project evaluation. The few such evaluation studies conducted have indicated a high percentage of failures. Thus, post-project evaluation (and dissemination of results) is essential if the field of river restoration is to advance. Effective evaluation of project success should include: (1) Clear objectives, essential to identity potential incompatibilities among project objectives and to provide a framework for design of project evaluation. (2) Baseline data, needed as an objective basis for evaluating change caused by the project and encompassing as long a pre-project period as possible (including a detailed historical study). (3) Good study design, to demonstrate the effects of restoration projects in the complex riverine environment. (4) Commitment to the long term, to detect effects evident only years following project completion; in general, monitoring should continue for at least a decade, with surveys conducted after each flood above a predetermined threshold. (5) Willingness to acknowledge failures, or rather to recognize that each restoration project constitutes an experiment, so that a failure can be just as valuable to the science as a success, provided we can learn from it (which requires objective, robust post-project evaluation).
Envisioning the loop movements and rotation of the two subdomains of dihydrofolate reductase by elastic normal mode analysis.

Abstract Normal mode analysis, using the elastic network model, has been employed to envision the low frequency normal mode motion trends in the structures of five intermediates and a transition state in the kinetic pathway of E. coli dihydrofolate reductase (DHFR). Five of the reaction pathway analog structures and a crystal structure resembling the transition state, using X-ray analyses determined by Kraut et al., have been adapted as structural models. The motions that poise pathways of the M20 loop transitions from closed to occluded conformations and sub domain rotation to close the substrate cleft, have been predicted and envisioned for the first time by this study. Pathway entries to the movement of the substrate binding cleft helices are also envisioned. These motions play roles in transition structure stabilization and in regulating the release of the product tetrahydrofolate (THF). The motions observed push the ground state conformation of each intermediate towards a higher energy sub state conf...
The kinetics of ring closure and hydrolysis of a number of halo-cobalt(III) complexes of diaminopolycarboxylate ligands

Abstract The kinetics of ring closure of Co(EDTA)Br 2− , Co (CyDTA)(H 2 O) - , Co(CyDTA)Cl − and the hydrolysis of Co(MEDTA)Cl-, Co(MEDTA)Br − and α-cis-Co(EDDA)Cl 2 − have been studied. a The remits suggest that an aqua intermediate does not occur in the ring closure reactions. Biphasic rates have been detected in the first-order reactions of the bromo complexes and this is ascribed to the presence of two isomers. One of these has been prepared and its structure is discussed. Oxidation of Co(EDDA)(H 2 O) 2 by Copy 4 Cl 2 + yields an isomeric mixture of Co(EDDA)(H 2 O) Cl.
Applications of the group-contribution, lattice-fluid equation of state

The group-contribution, lattice-fluid (GCLF) equation of state (EoS) is now more than 10 years old. The primary objective of our effort has been to develop a predictive model for the phase equilibria in polymer-solvent systems. The model has been developed by introducing group-contribution to the Panayiotou-Vera EoS. This paper reviews and updates the application of this approach along with its shortcomings. This EoS has been applied to prediction of the density of pure polymers, VLE of vapors, supercritical gas solubility, LLE, solubility parameters, and glass transition temperatures. Homopolymers and random copolymers can be successfully treated. The key features of this model are that it is purely predictive based only on the molecular structure of the molecules, and it is able to describe the pressure as well as temperature and composition effects because it is based on an EoS.
Turning the curve: A critical review of Kuznets approaches

Abstract The Environmental Kuznets Curve (EKC) and related approaches to human-environment problems (e.g., Forest Transition Theory) generally posit an inverted U-shaped relationship between environmental degradation and economic development, frequently utilizing a cross-national approach. After numerous years of research, the overall empirical evidence remains equivocal: case studies that appear to support key EKC hypotheses are contradicted by others that fail to demonstrate environmental recovery following increasing indices of economic development. This paper undertakes a critical review of EKC approaches, identifying their collective contributions and remaining gaps, and integrating insights from two case study regions in Mexico and Brazil relevant to a forest transition. The larger aim is to identify the arenas that hold the greatest promise for a re-conceptualization of EKC-related approaches to move from proximate understandings of environmental degradation/recovery patterns, to deeper explanations of the processes and institutions structuring those patterns across spatio-temporal scales. We argue that such a reworking is critical to comparative scientific analyses of dynamic and coupled human-environment systems, and for policy prescriptions targeting applied geographical issues and a transition towards sustainability at a variety of scales.
Laboratory-based project-oriented introductory course for electrical engineering

Based on evidence from assessment data and in discussions with engineering employers, the Electrical and Computer Engineering program at York College of Pennsylvania saw the need to revise its freshman engineering experience. This paper describes the need for this new course and discusses the architecture and pedagogy of the course. Of particular interest were the goals of ensuring all students developed proficiency in operating basic electric/electronic test equipment, skills in basic DC circuit analysis techniques, exposure to a broad range of electric/electronic devices, and introduction to fundamentals of engineering design. Consequently the course was primarily laboratory based and project oriented.
Present status of thermography, ultrasound and mammography in breast cancer detection

Various biophysical methods have been utilized in the diagnosis of breast cancer. To date the best results have been obtained with x-ray mammography. Ultrasound and thermography have great appeal as non-destructive techniques but, in the present state of development, are of limited use. The spatial resolution presently obtainable in ultrasonograms is inadequate for the detection of subclinical cancer and thermography is also of questionable reliability. While an overall true positive rate of 70% to 75% may be anticipated with thermography, the bulk of false negatives would seem to occur in those tumors most amenable to therapy, i.e., subclinical cancers. The "false positive" rate of thermography is also excessive, but would be acceptable for establishing a high risk group if true positive rates could be improved. At present thermography finds its greatest use as an adjunct to mammography and physical examination; it should not be used as the sole modality in a screening program. The efficacy of mammography can be readily demonstrated but the propriety of its use as a screening device has been questioned. This is primarily related to the possible carcinogenic effect of radiation at diagnostic levels. Although the carcinogenic effect is unproven, the dose in radiologic procedures should be kept to a minimum consistent with adequate images. The present state of the art would indicate that the risk, if any, is minimal as contrasted with the natural incidence of breast cancer and the results of early diagnosis and treatment.
Hydrogen and Temperature Effects on the Coverages and Activities of Surface Intermediates during Methanation on Ru/SiO2

Abstract Methanation on Ru can be considered to be a representative example of many hydrogenation reactions. Steady-state isotopic transient kinetic analysis (SSITKA), one of the most powerful surface kinetic techniques capable of in situ assessing reaction parameters such as abundance of surface intermediates and intrinsic activity, was used to study the effects of hydrogen partial pressure and temperature on the fundamental surface reaction parameters for methanation (for a fixed P CO of 0.036 bar) on Ru/SiO 2 . Although absolute hydrogen coverage under reaction conditions is not able to be measured due to the hydrogen isotope effect, relative hydrogen surface concentration as a function of P H 2 was able to be estimated at constant temperature from SSITKA parameters. Increasing the hydrogen partial pressure at constant temperature caused an expected increase in the relative surface concentration of hydrogen and a concomitant increase in the abundance of CH x species on the surface, N M , possibly due to increased hydrogenation. At higher partial pressures of H 2 , two active pools of methane intermediates (α and β) were able to be observed in the activity distribution analysis. However, at low P H 2 , only the most active species (α) was detected. It was found that N M was additionally dependent on temperature and deactivation. At low H 2 /CO ratios (H 2 /CO=5), no increase in N M with increasing temperature was detected, which is suggested to be an effect of site blockage by the formation of greater amounts of inactive surface carbon at higher temperatures. At low temperatures, both α- and β-carbon were observed in the activity distribution analysis. However, at higher temperatures the less active β-carbon could not be detected. This can probably be explained by a transformation of β carbon into inactive γ carbon under these conditions. At high H 2 /CO ratios (H 2 /CO=20), an increase in N M was observed with increasing temperature. This was attributed mainly to a more efficient hydrogenation of the surface active carbon.
Sulfonamide inhibition of rat hepatic uroporphyrinogen I synthetase activity and the biosynthesis of heme.

Abstract Sulfonamides are known to provoke attacks of acute intermittent porphyria, which is characterized by a deficiency of uroporphyrinogen I synthetase (EC 4.3.1.8) activity. Various sulfonamides were examined for their potential as inhibitors of purified rat hepatic uroporphyrinogen I synthetase activity in vitro , and 10 were found to be inhibitory. Inhibition of uroporphyrinogen I synthetase activity by sulfonamides is reversible by dialysis and exhibits noncompetitive kinetics. Inhibition constants ( K i ) ranged from 100 μ m for sulfaguanidine to 270 μ m for sulfadiazine. These observations were extended to in vivo studies using sulfamerazine ( K i = 250 μ m). Twenty-four hours after administration of sulfamerazine (orally; 1 g/kg) to male rats, hepatic microsomal heme and cytochrome P -450 contents were decreased approximately 33 and 42%, respectively. This was reflected by the inhibition of both aniline- p -hydroxylase and amino pyrine- N -demethylase activities, which are P-450 mediated. Heme oxygenase activity was not altered by sulfamerazine treatment. However, the relative rate of heme biosynthesis, as measured by the incorporation of δ-[4- 14 C]aminolevulinic acid into heme, was 28% lower in sulfamerazine-treated rats. Thus, these results indicate that sulfamerazine acts to inhibit heme biosynthesis. Hepatic δ-aminolevulinic acid synthetase (EC 2.3.1.37) activity was increased 2.2-fold in the sulfamerazine-treated group, which is probably a compensatory increase caused by depression of the heme content. Consequently, it is suggested that sulfamerazine inhibits the synthesis of heme at the Uroporphyrinogen I synthetase step to impair hemoprotein formation and cytochrome P -450-mediated hepatic drug metabolism.
Arthroscopic repair of SLAP lesions with a bioknotless suture anchor

The diagnosis and treatment of SLAP tears have improved with the development of arthroscopic shoulder surgery techniques. With types 2 and 4 tears, the goal is to restore stability to the labrum and biceps anchor and achieve healing to the glenoid. Suture repair with anchors is currently the repair technique of choice. The purpose of this article is to report a fast and simple method for arthroscopic SLAP repair that uses knotless suture anchors and obviates complex suture management and arthroscopic knot tying.
International education and sustainable development: an American experience in Bangkok, Venice and Guayaquil

Worcester Polytechnic Institute's (WPI) unique academic plan enables students to study sustainable development and the environment as part of an international educational experience. As a technological university, WPI requires students to complete an interdisciplinary project on the interaction of science or technology and society. This paper describes the environmental projects completed by WPI students, in Bangkok, Venice and Guayaquil. The lessons from WPI's experience provide a model for environmental education at other institutions. These interdisciplinary projects not only promote environmental awareness among students, but they also provide tangible assistance to regions which are developing strategies for sustainable development.
Assessing Assay Variability of Pesticide Metabolites in the Presence of Heavy Left-Censoring

Assessing assay variability for field samples in environmental research is challenging, since a quantitative assay is typically constrained by a lower limit of detection. The purpose of this paper is to compare three parametric models for assessing assay variability using duplicate data subject to heavy left-censoring. Efron information criterion (EIC) and Bayesian information criterion (BIC) are used to aid in model selections. Distributional parameter estimates are obtained using maximum likelihood estimation for bivariate lognormal, bivariate zero-inflated lognormal, and bivariate 3-component mixture models. We illustrate a practical application using duplicate pesticide data from the Community Participatory Approach to Measuring Farmworker Pesticide Exposure (PACE3) study. Furthermore, a simulation study is conducted to empirically evaluate the performance of the three models. The results from PACE3 indicate that the bivariate zero-inflated lognormal model is fairly competitive based on EIC or BIC. Further, total variability for the lognormal component can be decomposed into between-subject and within-subject variance based on this model. Assay variability estimates such as within-subject coefficient variation, minimum detectable change, and probability of k-fold difference can be easily derived under the bivariate zero-inflated lognormal model. Additionally, the assay variability is rather large for the PACE3 data. Therefore, apparent longitudinal change in pesticide exposure should be examined cautiously in the context of substantial assay variability.