cssi/SciSciGPT-SciSciNet huggingface dataset:
Abstract B42: Dichotomus role of profilin in early vs. late steps of breast cancer metastasis

Profilin1 (Pfn1), an essential control element for actin polymerization, plays indispensable role in migration and proliferation of normal cells. Seemingly contrary to these essential cellular functions of Pfn1, its expression is downregulated in breast cancer, the significance of which is unclear. In this study, expression profiling of Pfn1 in human breast cancer specimens of various histopathological stages correlate lower Pfn1 expression levels with propensity to metastasize. Xenograft studies uncover a unique dichotomous role of Pfn1 in early vs late steps of breast cancer metastasis. Specifically, loss of Pfn1 expression promotes dissemination of breast cancer cells from the primary mammary tumor but metastatic colonization of breast cancer cells is critically dependent on Pfn19s function. In the context of dissemination, breast cancer cells exhibit increased sustenance of PI3K signaling and acquire a hyper-invasive phenotype (marked by MMP9 upregulation, faster invasion through collagen matrix) involving a PI3K-PI(3,4)P2 signaling axis when Pfn1 expression is suppressed. In addition, Pfn1-deficient breast cancer cells display increased proficiency to cross through an endothelial cell barrier (an obligatory step for vascular dissemination) in a VEGF-dependent manner, respectively. Gene expression profiling combined with biochemical analyses of secreted proteins show that loss of Pfn1 impacts expression of several other pro-invasive and pro-metastatic genes. Finally, correlated with hyper-invasive phenotype of breast cancer cells caused by Pfn1 depletion, we found that mammary-specific deletion of Pfn1 gene expedites ductal outgrowth. In summary, contrasting the well-established pro-migratory role of Pfn1 in the physiological contexts, our findings set the first in vivo example of a context-specific effect of loss of Pfn1 in cell motility-dependent processes such as mammary gland morphogenesis and metastatic dissemination. Citation Format: Partha Roy. Dichotomus role of profilin in early vs. late steps of breast cancer metastasis. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr B42.
Effective nuclear interactions

Abstract The energy level spectra of O17, O18, O19 and O20 are analysed in the framework of the nuclear shell model. The matrix elements of the effective interaction in various two-particle states are deduced. It is shown that the singlet even interaction is not only short-ranged and attractive, but also contains a strongly repulsive central region. This demonstration of a repulsive non-singular core is the essential conclusion of this paper. It is also suggested that it may not be possible to represent the effective triplet odd interaction by a simple central potential. An experimental determination of the 3+ state in O18 would throw further light on this question. The excitation energy of this state is predicted.
Catalytic dehydrogenation of propane over iron-silicate zeolites

Abstract Isomorphously substituted iron-silicate zeolites were prepared and their catalytic properties for the monomolecular propane reaction were investigated. [Fe]ZSM-5 (MFI) samples with Si/Fe ratios of 26 and 48, and [Fe]beta zeolite (BEA*) with Si/Fe ratio of 15 were synthesized and characterized using X-ray powder diffraction (XRD), N2 adsorption and ultraviolet–visible (UV/Visible) spectroscopy. Unit cell volumes, determined using XRD, were used to monitor the presence of Fe in the framework and the migration of Fe species from framework to extra-framework positions. Most of the Fe atoms remain in framework positions after mild calcination (753 K in air), but most of the Fe species migrate to extra-framework positions after steaming at 973 K. Migration of Fe species from framework to extra-framework positions can occur during the monomolecular propane reaction as well. Isolated framework Fe sites are the most important sites for hydrocarbon conversion even though Fe species in extra-framework positions also showed catalytic activity for dehydrogenation. The iron-silicate zeolites exhibited nearly 20 times higher dehydrogenation rates than cracking rates while H-[Al]ZSM-5 with similar Si/Al ratio (∼26) showed low dehydrogenation selectivity (dehydrogenation–to-cracking ratio ∼0.36). The activation energy for H-[Fe]ZSM-5 is also lower than the activation energy for H-[Al]ZSM-5. A redox catalytic cycle is suggested for the hydrocarbon reaction over isolated Fe framework sites in [Fe] zeolites via the formation of propane radical cations since a protolytic mechanism seems to be unable to explain the observed differences in activation energy and selectivity.
Propensity to Support Sustainability Initiatives: A Cross-National Model

Businesses and the social sciences are increasingly facing calls to further scholarship dedicated to understand sustainability. Furthermore, multinationals are also facing similar calls given their high profile and their role in environmental degradation. However, a literature review shows that there is very limited understanding of sustainability at a cross-national level. Given the above gaps, we contribute to the literature by examining how selected GLOBE [House et al., Culture, leadership and organizations: The GOBE study of 62 societies. Sage Publications, Thousand Oaks, 2004] cultural dimensions are related to individuals’ propensity to support sustainability initiatives in 33 countries. We use data from the World Values Survey [World Values Study Group, World Values Surveys and European Value Surveys, 1999–2001. Inter-University Consortium for Political and Social Research, Ann Arbor, 2004] and test our hypotheses using Hierarchical Linear Modeling (HLM). Results support all but one hypothesis. Specifically, uncertainty avoidance is not related to propensity to support sustainability initiatives. In contrast, performance orientation and assertiveness have the desired negative relationship with our dependent variable while collectivism, future orientation, and human orientation have the desired positive relationship. We discuss the conceptual and practical implications of this study.
On the distribution of the fourier spectrum of Boolean functions

In this paper we obtain a general lower bound for the tail distribution of the Fourier spectrum of Boolean functionsf on {1, −1}N. Roughly speaking, fixingk∈ℤ+ and assuming thatf is not essentially determined by a bounded number (depending onk) of variables, we have that\(\sum {\left| s \right| > k\left| {\hat f(S)} \right|^2 } \gtrsim k^{ - 1/2 - \varepsilon } \). The example of the majority function shows that this result is basically optimal.
The Catholic Church and Political Mediation in the Dominican Republic: A Comparative Perspective

This essay looks at the Catholic Church and political mediation in the Dominican Republic during the 1980's and 1990's. It opens with a review of the Latin American context regarding the transition to democracy, the debt crisis, and the church's response to the new political reality. It draws some comparisons from Bolivia, Nicaragua, El Salvador, and Guatemala, where the church played an important role mediating political conflicts. The core of the article concentrates on three parts: the Dominican transition to democracy, the church mediation in the Tripartite Dialogue of the 1980's and early 1990's, and in the general elections of 1986 and 1994.
A comparison of nutrient losses from two simulated pastureland management scenarios

Fecal deposits by grazing animals on pasturelands have the potential to leach nutrients to runoff during rainfall events. Unlike croplands, grazing systems such as pasturelands or rangelands have little opportunity to ameliorate nutrient runoff through in-field or edge-of-field management practices. Thus, we investigated the amounts and concentrations of nutrients in overland flow from simulated grazing lands. Two grazing management scenarios were simulated: continuous grazing represented by two sparsely vegetated (SV) plots and rotational grazing represented by two densely vegetated (DV) plots. In addition, there were two control plots. The plots were treated with standard cowpats and rainfall was simulated until overland flow at the edge of the plots reached steady-state. Higher runoff was observed from DV plots (9.97 mm) than SV plots (7.05 mm), but the average total suspended solids concentration in runoff from SV plots was approximately 17 times the concentration observed in runoff from the DV plots. The average total phosphorus (TP) concentrations were highest in plots simulating continuous grazing (5.91 mg L−1). In both DV and SV plots at least 83% of the TP was found to be in the dissolved form. The average total Kjeldhal nitrogen (TKN) and total nitrogen concentrations observed in runoff samples from SV plots were 1.25 and 1.46 mg L−1, respectively. Organic nitrogen comprised 95% of the TKN observed in runoff samples from SV plots. The SV plots have relatively higher loads for those nutrients in the particle associated form compared to DV plots, whereas DV plots had higher loads for those nutrients in the dissolved form. Grazing lands without any additional manure applications were found to release nutrients in high levels and vegetation did not show any effect on removing dissolved nutrients from runoff. These results are useful to inform selection of appropriate management practices to reduce nutrient transport to surface waters in watersheds dominated by grazed lands.
Does hydrogen peroxide exist “free” in biological systems?

Hydrogen peroxide (H2O2) can diffuse far from the site of production to intracellular locations where biological effects may be greater. The diffusion range is extended by H2O2 carriers formed spontaneously by hydrogen bonding with monomeric and polymeric compounds, including amino and dicarboxylic acids, peptides, proteins, nucleic acid bases, and nucleosides. Hydrogen peroxide adducts (HPAs) are readily synthesized, e.g., crystalline histidine (His)-H2O2 adducts. An equilibrium exists between an adduct-forming compound and H2O2. The detection and relative stabilities of HPAs are measured by the degree of decomposition of H2O2 as influenced by test compounds in buffered solution competing with glucose or fructose for H2O2. The HPAs delay decomposition of H2O2 up to several hundredfold. The overall charge on an HPA, i.e., its ability to penetrate cell membranes, influences the cytotoxic and clastogenic effects of H2O2. Growth inhibition of Salmonella typhimurium LT2 by H2O2 is enhanced by neutral HPAs but decreased by anionic HPAs. Addition of catalase 1, 10, or 30 min after inoculation of S. typhimurium LT2 reduces or nearly eliminates partial growth inhibition by H2O2, but a neutral HPA, especially His-H2O2, transported H2O2 into the cells within 1 min, and in about 10 min completely inhibited growth. The stability of HPAs decreases with increasing pH or increasing temperature, while added Fe(II) in the presence and absence of EDTA accelerates H2O2 and HPA decomposition. Calculations indicate H2O2 hydrogen bonds with nucleic acid-base pairs with no apparent bond strain and energy stabilization comparable to normal hydrogen bonding.
Laterally driven electrostatic actuators with extended travel range

A novel laterally driven mechanism is proposed and studied to solve the pull-in problem of electrostatic actuation in MEMS for use in simple Fabry-Perot interferometers (FPI) with a large tuning range. This method is to build electrodes that are not directly opposite to each other, but rather are laterally shifted. Mathematica calculations show that laterally driven beams require a smaller operating voltage than do some other methods, and cover nearly the full travel range. It is also found that driving performance is influenced by the structure's lateral gap. Too small a lateral gap still yields pull-in failure. For excessively large lateral gap, the pull-in function is not effective. Smaller lateral gaps have lower operating voltage, but larger lateral gaps have better operating stability. A test structure consisting of 40 aluminum beams suspended across two poles has been designed and fabricated. Directly below each test beam is located a capacitive test electrode. Next to each test electrode are two lateral driving electrodes. A driving voltage is applied across the aluminum test beams and lateral electrodes, pulling down the beam and causing the capacitance to change between the test beam and test electrode. By measuring this change, the lateral drive method is verified and characterized.
Isolation and characterization of a human mononuclear cell Fc receptor

Abstract These studies show that human peripheral mononuclear cells have a surface receptor of 60,000 mol. wt (and possibly a disulfide bonded dimeric form of 120,000) which has affinity for heat-aggregated human IgG, IgG 1 myeloma proteins, or the Fc + fragments of either of these but not to F(ab') 2 fragments of IgG. Precipitates of this receptor contain 0.5–1% of the total number of TCA precipitable counts incorporated into the surface membrane. Since this structure was found trysininsensitive and was not identified on the cell membranes of cultured human T cell lines, it appears to be a surface receptor for the Fc portion of IgG.
The role of glucagon in the control of protein and amino acid metabolism in vivo

The relative contribution of hyperglucagonemia to the mechanisms of nitrogen loss during catabolic states has not been clearly established. The present study examines the independent effect of physiologic elevations of plasma glucagon on whole-body protein kinetics, as well as on net amino acid balance across the liver and gastrointestinal tract tissues, in conscious 18-hour-fasted dogs (n = 7). Each study consisted of a 120-minute equilibration period, a 30-minute basal period, and a 150-minute experimental period. Leucine kinetics were measured using L-[1-14C]leucine. Pancreatic hormones were maintained by infusing intravenous somatostatin (0.8 micrograms/kg.min), intraportal insulin (275 microU/kg.min), and intraportal glucagon (0.65 ng/kg.min basally and 2.5 experimentally). Dextrose was infused to maintain plasma glucose constant (14.1 +/- 0.3 mumol/L), thereby providing a consistent metabolic steady state for the study of protein and amino acid metabolism. In the experimental period, plasma glucagon was fourfold basal levels (112 +/- 10 v 32 +/- 6 pg/mL), whereas plasma insulin remained stable (mean, 10 +/- 1 microU/mL). Hepatic glucose production was increased 30%, but leucine rates of appearance ([Ra] proteolysis), oxidative disappearance (Rd), and nonoxidative Rd (protein synthesis) were not altered during the experimental period. Furthermore, the net release of amino acids by the gastrointestinal tract was not increased by glucagon. However, uptake and extraction of amino acids by the liver were increased, resulting in a 17% decrease in total plasma amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)
Studies of chloroplast development in Euglena. I. Inactivation of green colony formation by u.v. light.

Abstract Irradiation of Euglena gracilis with non-lethal doses of u.v. light prevents the formation of chloroplasts in the progeny. This inactivation is photoreactivable with efficiencies approaching 100%. The albino cells produced through irradiation form colorless clones which never revert to green, indicating that this is a heritable effect. The action spectrum for u.v. inactivation of chloroplast formation shows peaks at 260 and 280 mμ.implicating nucleoprotein as the probable site of u.v. action. Evidence obtained from the inactivation kinetics of dark-grown and light-grown cells, the presence of sectored colonies after u.v., the lack of lethality, and the multiplicity of inactivation sites suggest to us that the u.v. sensitive site is cytoplasmic. The evidence leads us, then, to the hypothesis that there are self-reproducing cytoplasmic entities in Euglena which contain nucleoprotein and which are responsible for chloroplast formation.
Newborn screening programs: should 22q11 deletion syndrome be added?

The highly variable 22q11 deletion syndrome has been proposed for addition to newborn screening panels. A literature review investigated the incidence and prevalence, clinical features, and prognosis of 22q11 deletion syndrome and other issues related to newborn screening. Severe complications that could potentially be helped by screening include cardiac defects in 80% (with 20% having no outward signs to aid detection), hypocalcemia that can lead to seizures in 20% (though hypocalcemia is routinely investigated in sick newborns), and severe immune deficiency in 1:5000, undetected life-threatening effects occur in a minority of 22q11 deletion syndrome patients. Concerns include an untested screening technique, difficulty obtaining results in time for cardiac intervention, the chance of "vulnerable child syndrome" in mild cases, and possibly detecting congenital heart disease more efficiently by other means. Because addition of tests for highly variable conditions such as 22q11 deletion syndrome is likely to set a precedent for other syndromes, reevaluation of newborn screening criteria should be considered.
Effect of tile effluent on nutrient concentration and retention efficiency in agricultural drainage ditches

Abstract Tile drainage is a common water management practice in many agricultural landscapes in the Midwestern United States. Drainage ditches regularly receive water from agricultural fields through these tile drains. This field-scale study was conducted to determine the impact of tile discharge on ambient nutrient concentration, nutrient retention and transport in drainage ditches. Grab water samples were collected during three flow regimes for the determination of soluble phosphorus (SP), ammonium nitrogen (NH 4 + -N), nitrate nitrogen (NO 3 -N) concentrations and their retention in three drainage ditches. Measured nutrient concentration indicated lower SP and NH 4 + -N, and greater NO 3 -N concentrations in tile effluents compared to the ditch water. Net uptake lengths were relatively long, especially for NO 3 -N, indicating that nutrients were generally not assimilated efficiently in these drainage systems. Results also indicated that the study reaches were very dynamic showing alternating increases or decreases in nutrient concentration across the flow regimes. The drainage ditches appeared to be nutrient-rich streams that could potentially influence the quality of downstream waters.
Heterochromatin dispersion and blebbing of the nuclear membrane induced by melanophore stimulating hormone.

Stimulation (in vivo and in vitro) of dermal melanophores of the leaf frog, Agalychnis dacnicolor, by melanophore stimulating hormone (MSH) elicits two responses in addition to the dispersion of melanosomes: (1) dispersion of heterochromatin; and (2) blebbing of the outer membrane of the nuclear envelope. The latter leads to the formation of dilated rough endoplasmic reticulum with the involvement of 80–100 A microfilaments. N6,O2-dibutyryl adenosine 3′,5′-monophosphate (db-cAMP) elicits a similar response. Actinomycin D prevents both heterochromatin dispersion and membrane blebbing while cytochalasin B (CB) prevents only the latter.
The effect of portacaval transposition and renal artery stenosis on the rejection of renal allografts in dogs

Abstract Hypertension during acute renal allograft rejection was prevented in five animals by subcutaneous injection of reserpine, and in 11 animals by prior performance of portacaval transposition and renal artery stenosis. Whereas 14 control animals with normal circulation dissolved their kidneys over a 2-week period with a rapid exudative response, the two groups of animals kept normotensive dissolved their graft kidneys over a 6-week period, and with less necrosis. It is suggested that hypertension alone accelerated graft dissolution by increasing tissue ischemia.
Understanding design considerations for adaptive user interfaces for accessible pointing with older and younger adults

The Internet has become an important tool for many aspects of modern life. However, some individuals may experience challenges accessing the Internet if they have difficulty accurately controlling a pointing device. These pointing problems can vary in severity and frequency and may be caused by a motor impairment, limited hand dexterity, or fatigue. We believe that adaptive user interfaces (AUIs) offer a unique solution to detect and accommodate an individual's current pointing behavior. While past work has explored the implementation of detecting pointing challenges and designing adaptations, little has been done to understand how this population would like to interact with this software. In this paper, we present the results from participatory design sessions with older and younger adults that highlight their preferences for novel AUIs. We found diverse preferences and attitudes towards how AUIs notify a user of their current performance, and how they should adapt to pointing behavior. We present these diverse opinions as three personas that can be applied to future design of any AUI.
Activation of mitogen-activated protein kinase phosphatase 2 by gonadotropin-releasing hormone.

Abstract The aim of these studies was to identify the signaling mechanism(s) that contribute to GnRH-induced expression of MAPK phosphatase (MKP)-2, a dual specificity phosphatase that selectively inactivates MAPKs. GnRH receptor activation induced MKP-2 expression in both clonal (αT3-1) and primary gonadotropes. Activation of PKC isozymes was sufficient and required for MKP-2 induction. Inhibition of the extracellular signal-regulated kinase (ERK) or c-Jun N-terminal kinase (JNK) but not the p38 MAPK cascade was sufficient to block GnRH-induced MKP-2 expression. Induction of MKP-2 by GnRH was dependent on elevation in intracellular Ca 2+ . Inhibition of Ca 2+ influx through L-type voltage-gated calcium channels blocked GnRH-induced MKP-2 expression. Depletion of intracellular Ca 2+ stores with thapsigargin blocked MKP-2 activation by GnRH independent of ERK and JNK activity. These results support the conclusion that MKP-2 induction by GnRH occurs via MAPK-dependent and -independent pathways. One mechanism requires GnRH-induced ERK and JNK activation, while a second MAPK-independent pathway requires a thapsigargin-sensitive calcium signal.
Diagnosis and Treatment of Children and Adolescents with Attention-Deficit/Hyperactivity Disorder.

Attention-deficit/hyperactive disorder (ADHD) has been estimated to affect between 3% and 5% of school-age children. The disorder frequently has a profound effect on a child's personal, social and academic development and is a risk factor in the development of other comorbid disorders. Diagnostic criteria and methods for identification of ADHD will be presented. Major intervention strategies appropriate for school and community settings are outlined. Because ADHD is 1 of the most common reasons for referral in both school and community agencies, it is important that clinicians be prepared to provide accurate diagnosis and intervention recommendations.
Theory and practice of software engineering

For twenty years software has cost more than planned, has been completed late, and failed to achieve what it was intended to do. There exists gaps between theory, curriculum, and practice. I have been trying to fill in the gaps for 15 years.In 1985 I presented a paper that listed more than 20 activities that can improve the production of software. Some of these lack a theoretical justification for their empirical success. Many of the 20 activities are not part of the Computer Science curriculum. I focussed on Jackson Structured Programming(JSP), Jackson Software Development(JSD), and parts of the Structured analysis and Design Method developed in the UK Civil Service.In 1986 I defined Dynamic Analysis and Design(DAD) and argued for its inclusion in software engineering. I demonstrated DAD in 1987. In 1987 I proved that Data Directed Design is significantly more powerful than is commonly thought. This lead to unexplored regions of logic and language theory (1988--89). For example, a small change in the model of context free grammars makes it possible for a BNF-like data dictionary to describe non-context-free languages.In parallel I have studied the time it takes to access data on secondary storage and proved that the text book formulae can be misleading (1988). For example a binary search of n items held in a large contiguous file on a disk on a personal computer takes time of order to n and not log(n) to retrieve information.
Parent-Child Interaction Therapy for ADHD: A Conceptual Overview and Critical Literature Review

ABSTRACT Attention-Deficit/Hyperactivity Disorder (ADHD), a chronic disorder beginning in childhood, is identifiable and diagnostically valid during the preschool years. Compared to school-aged children, preschoolers have not received as much attention in the literature. Parent-Child Interaction Therapy (PCIT) is an empirically-supported parent training program for young children with disruptive behaviors that may also be effective in treating ADHD. The purpose of the current article was to explore the theoretical rationale for utilizing PCIT with this population and to conduct a literature review of published PCIT treatment outcome studies that measured ADHD symptoms. The literature demonstrates that children with ADHD have been included in PCIT research and evidence suggests that PCIT may be effective for young children with ADHD. However, future research is needed to specifically examine the effects of PCIT on ADHD.
EFFECTS OF INCOMPLETE MIXING ON MULTICOMPONENT REACTIVE TRANSPORT

Darcy-scale description of multicomponent reactive transport can significantly over-predict the extent of mixing-controlled reactions. Here we present a systematic pore- and Darcy-scale study of multicomponent reactive transport for various Peclet (Pe) and Damkohler (Da) numbers. We use pore-scale simulations to parameterize and validate Darcy-scale model. Our results reveal that for small Pe, the Darcy-scale model of mixing-controlled reactions is accurate, but its accuracy deteriorates with increasing Pe. The dilution index is calculated based on the pore-scale simulations as a measure of the degree of true solute mixing (dilution) for different Pe. We find that true mixing decreases with increasing Pe. A strong correlation is found between the magnitude of the dilution index and the error in the Darcy-scale model prediction. The error (over-prediction of the mass of a product of the mixing-controlled reaction) increases with decreasing dilution index (reduced dilution).
Response of the testicular capsule to acetylcholine and noradrenaline.

WE have used the testicular capsule as an isolated tissue preparation for pharmacological studies, and we describe here the first response of the capsule to a pharmacological agent.
The Use of the Minimum Data Set to Identify Depression in the Elderly

Objective To determine whether depression in the elderly in institutionalized settings could be identified using the mood indicators in the Minimum Data Set (MDS) 2.0 (Section E1, Items A-P). Design Descriptive study. Setting Three nursing homes in the southeastern part of the country. Participants Residents aged 65 and above. Measurements The items in “Indicators of Depression, Anxiety and Sad Mood” on the MDS 2.0 were used to identify observable features of depression in the elderly. The Cornell Scale for Depression in Dementia (CSDD) was used to validate the MDS indicators. Consensus analysis, which controls raters’ bias, raters’ ability, and item difficulty, was used to analyze data. Results No depressive patterns were detected using the MDS indicators. On the CSDD, distinct depressive features were identified: anxiety, sadness, lack of reaction to pleasant events, irritability, agitation, multiple physical complaints, loss of interest, appetite loss, and lack of energy. Conclusion The incongruent findings on the MDS indicators and the CSDD may be reflective of the assessment process used with the MDS rather than its ability to identify features of elderly depression. The practice of allowing nondirect caregivers to complete the MDS may have serious implications for the accuracy of the data collected.
Distress in European Banks: An Analysis Based on a New Dataset

The global financial crisis has highlighted the importance of early identification of weak banks: when problems are identified late, solutions are much more costly. Until recently, Europe has seen only a small number of outright bank failures, which made the estimation of early warning models for bank supervision very difficult. This paper presents a unique database of individual bank distress across the European Union from mid-1990s to 2008. Using this data set, we analyze the causes of banking distress in Europe. We identify a set of indicators and thresholds that can help to distinguish sound banks from those vulnerable to financial distress.
The snow cover on lakes of the Arctic Coastal Plain of Alaska, U.S.A.

Shallow lakes cover >25% of Alaska’s Arctic Coastal Plain. These remain frozen and snow-covered from October to June. The lake snow is thinner, denser, harder and has less water equivalent than snow on the surrounding tundra. Itcontains less depth hoar than land snow, yet paradoxically is subject to stronger temperature gradients. It also has fewer layers and these have been more strongly affected by wind. Dunes and drifts are better developedon lakes; they have wavelengths of 5–20 m, compared to <5 m on land. Because of these differences, lake snow has roughly half the thermal insulating capacity of land snow. The winter mass balance on lakes is also different because (1) some snow falls into the water before the lakes freeze, (2) some snow accumulates in drifts surrounding the lakes, and (3) prevailing winds lead to increased erosion and thinner snow on the eastern lake sides. Physical models that extrapolate land snow over lakes without appropriate adjustments for depth, density, distribution and thermal properties will under-predict ice thickness and winter heat losses.
Interference detection using barycentric coordinates

Abstract In summary algorithms using barycentric coordinates have been presented which allow for the simplified testing of whether or not a point lies inside or outside of a triangle or tetrahedron or whether a given line segment intersects a triangle or tetrahedron. Along with the algorithms two formulas were presented for establishing the perpendicular distance from a point to a given side of a triangle or tetrahedron. Finally it should be pointed out that other algorithms are known for solving the problems posed in this paper. They occur in the literature under the general heading of Computational Geometry [4].
What Will I Be? Exploring Gender Differences in Near and Distant Possible Selves

We investigated whether the possible selves of men and women align with the gender-differentiated social roles that are projected to vary across the lifespan. Across two studies (Study 1: N = 211 and Study 2: N = 314) of college students in the Midwestern U.S., we found that gender differences in possible selves were larger when projected into the distant future (e.g., 10–15 years) than the near future (1 year). In addition, the relationship between career and family possible selves varied depending on gender and temporal distance, with a tradeoff between career and family observed primarily among women and for distant possible selves (Study 1). Supporting role congruity theory, both genders hoped for role-congruent selves but feared role-incongruent selves (Study 2).
Identity Brokerage and Nonprofit Community Building

Scholars have increasingly approached organizations as complex systems with indeterminate, shifting boundaries. Boundaries in many nonprofit organizations may be especially fluid, given the heterogeneity of stakeholders and highly multiplexed relational and value characteristics involved in constructing identity. The present study frames nonprofit organizations as complex organizations seeking to build communities of legitimacy. Within these communities they construct their identity through a combination of boundary setting, or perceptions of the organization and in what ways it is distinct from other organizations and communities, and relationship building, through both interpersonal contacts and socially mediated interaction. These dimensions combine to allow organizations to identify and bridge structural holes in the larger network in which they are embedded, through processes of identity brokerage. These mechanisms have significant implications for driving growth and engagement in nonprofit organizat...
Natural killer cell activity in chronic lymphocytic leukemia patients treated with fludarabine

Fludarabine, the 5′-monophosphate of 9-β-D-arabinofuranosyl-2-fluoroadenine (FaraAMP), is effective in the treatment of chronic lymphocytic leukemia (CLL) and has been demonstrated to increase natural killer (NK) cell lytic activity (NKa) in humans and mice. To determine the effect of FaraAMP on NK cells in CLL, we analyzed NKa toward K562 targets after in vitro incubation with FaraAMP and after in vivo exposure to fludarabine. Pretreatment analysis of peripheral blood from 12 CLL patients (9 untreated) revealed: median number of NK cells 500/µl (range 290-1160); median NKa lytic unit30/106 cells (range 5–80). These results were similar to those from healthy adult donors. After exposure to 3, 30, or 300 µM FaraAMP, the median maximum stimulation index (NKa FaraAMP/NKa) was 1.2 (range 0.9-1.5), within the range observed in normal adults. FaraA also stimulated NKa in vitro toward autologous CLL cells in two of five patients as measured by a dye-exclusion assay. In three patients following three or more treatment courses of fludarabine (30 mg/m2 per day for 5 days) the NK cell number and NKa were maintained near pretreatment values. Phenotypic analysis of the peripheral mononuclear cells in 34 consecutive CLL patients revealed a marked reduction in CD5/CD20 and CD4 cell numbers after three courses of fludarabine with less effect on CD8 and CD56 cells. These results indicate that fludarabine spares NK cells and may stimulate NKa in some CLL patients.
Effects of CA Antagonists on Ethanol-Induced Excitation in Habituated and Nonhabituated Mice: Interaction With Stress Factors?

Abstract The effects of CA antagonists on ethanol induced locomotion in habituated (H) and nonhabituated (NH) mice was examined. H-mice were exposed to the testing apparatus for 4 days before testing. Mice were pretreated with pimozide (D 2 antagonist), Schering 23390 (D 1 antagonist), phenoxybenzamine ( α 1 antagonist), or yohimbine ( α 2 antagonist). Mice were then treated with ethanol. H mice had lower activity scores compared to NH mice. Ethanol produced an increase in activity for both groups. In NH animals, pimozide attenuated excitation in inverse relation to the ethanol dosage. In H mice, pimozide attenuated excitation only at doses that in themselves produced a decrease in activity. Schering 23390 reduced excitation only at doses that affected activity per se in both groups. Phenoxybenzamine reduced excitation dose-dependently in both groups. Yohimbine decreased excitation in both groups. Results suggest that stress emanating from a novel environment may effect not only activity per se but also the interaction between CA antagonists and ethanol.
Seasonal changes in xanthophyll cycle-dependent energy dissipation in Yucca glauca nuttall

The evergreen species Yucca glauca was characterized at the end of September and following exposure to low temperatures at the end of November. In November the diurnal pattern of xanthophyll cycle-dependent energy dissipation was altered such that this thermal dissipation process was engaged at a high level throughout the day, whereas in September it only became engaged when leaves received direct sunlight. An analysis of the diurnal partitioning of the absorbed excitation energy into photochemistry versus thermal dissipation suggested that a smaller fraction of that energy was utilized in photochemistry and a greater fraction was dissipated thermally at the end of November compared to September. Lower ratios of Chl a/b and β-carotene/xanthophylls both suggested a decrease in the ratio of reaction centre plus core antenna proteins compared to light-harvesting proteins, and a lower leaf chlorophyll content suggested a decrease in light-harvesting capacity in November versus September. Thus adjustments to the photosynthetic apparatus occurred on several levels in response to the increase in excess excitation energy that Y. glauca experienced during the onset of winter.
Repression of the embryonic myosin heavy chain phenotype in regenerating chicken slow muscle is dependent on innervation

Ventricular-like and fast myosin heavy chains (VL-MHC and FMHC) are transiently expressed during slow skeletal muscle development. The influence of innervation on repression of these MHC isoforms is investigated over an 84-day time course in: (1) normal anterior latissimus dorsi (N-ALD) muscles, (2) regenerating ALD (R-ALD) muscles, (3) denervated ALD (D-ALD) muscles, and (4) regenerating and denervated ALD (RD-ALD) muscles. Western blotting demonstrates that the VL-MHC is expressed in R-, D-, and RD-ALD muscles, but not in N-ALD muscles. Expression of the VL-MHC is transient in R-ALD muscles. In contrast, VL-MHC expression persists in RD-ALD muscles, and appears with time in D-ALD muscles. FMHC was not detected in N-ALD muscles by Western blotting. Two FMHCs are seen in R-ALD and RD-ALD muscles, and in 13-day embryonic ALD muscles. The slower migrating FMHC (FMHCA) comigrates with developmentally regulated FMHCs in fast pectoralis muscle, while the faster migrating FMHC (FMHCB) comigrates with the faster migrating FMHC in embryonic ALD muscle (13 days in ovo). FMHCB decreases in amount over the time course in R-ALD muscles, while FMHCA persists. In contrast, substantial levels of both FMHCs persist in RD-ALD muscles, and appear with time in D-ALD muscles. The cellular distribution of MHCs is followed by immunocytochemistry. Regenerating cells expressing VL-MHC and FMHC are replaced by a mature population in R-ALD muscles. Some of the mature myofibers in R-ALD muscles express FMHC, but not VL-MHC. In RD-ALD and D-ALD muscles, both regenerating and mature muscle cells are seen which express VL-MHC and FMHC. Our results indicate that innervation is required for the repression of VL-MHC and FMHCB during regeneration of slow muscle.
Biotic and abiotic factors regulating forest floor CO2 flux across a range of forest age classes in the southern Appalachians

Summary We measured forest floor CO 2 flux in three age classes of forest in the southern Appalachians: 20-year-old, 85-year-old, and old-growth. Our objectives were to quantify differences in forest floor CO 2 flux among age classes, and determine the relative importance of abiotic and biotic driving variables. Forest floor CO 2 flux was measured using an openflow infrared gas analyzer measurement system for 24 h periods and samples were taken every 2 months over a 2-year period. Litter/soil interface, soil temperature (5 cm depth), soil moisture (%), forest floor moisture (%), forest floor mass, fine root (⩽2 mm) mass, coarse root mass (>2 mm), forest floor C and N (%), fine root C and N, coarse root C and N, and soil N and C were co-measured during each sample period. Results showed significant nonlinear relationships ( r 2 =0.68 to 0.81) between litter/soil interface temperature and forest floor CO 2 flux for all three forest age classes, but no differences in temperature response parameters. These results indicated no differences in forest floor CO 2 flux among age classes. Considerable temporal variation in abiotic and biotic variables was observed within and among forests. Biotic variables correlated with forest floor CO 2 flux included indices of litter and root quality. Differences in biotic variables correlated with forest floor CO 2 flux among forests may have been related to shifts in the relative importance of heterotrophic and autotrophic respiration components to overall forest floor CO 2 flux.
Coexistence of long range order with glassy low frequency kinetics in random site electric dipole systems

Abstract We show that low frequency dispersion of dielectric constant and hysteresis loop above Tc can be explained by the existence of metastable states formed by clusters of close spaced dipoles. Interactions between clusters are responsible for ferroelectric ordering if dipole-dipole interaction possesses ferroelectric component like that in KTaO3:Li, Nb.
Studies on the infectivity and cytopathology of Epstein-Barr virus in human lymphoblastoid cells.

The infectivity of EB virus recovered from cultures of P-3J and the HR1K clone of this cell line has been demonstrated in established lymphoblastoid cell lines derived from healthy human donors and from patients with neoplastic disease. Filtered virus concentrates induced cell alterations similar to those produced by other members of the herpes group of viruses. Cell responses observed were: 1) an acute cytopathic effect evident within 16–72 h and characterized by cell swelling, polykaryocyte formation and progressive degeneration, and 2) a less severe CPE with minimal cell swelling and degeneration followed by either the establishment of a carrier culture or more often a culture in which the virus eventually disappeared. Characteristic non-enveloped herpes-virus-type particles were seen in the cell nucleus as early as 16 hours post exposure to virus and, subsequently, enveloped virions were found in the cytoplasm. A non-productive or abortive infection of the lymphoblastoid cells was indicated by the higher incidence of cells showing viral antigen by immunofluorescence, than the presence of virus particles. The infectivity of EBV was neutralized by human sera containing antibodies reactive with the viral envelope.
City size and skill intensity

Abstract Many have theorized that the productivity of human capital increases with city size. If this were true, one would expect production in large cities to be more skill intensive than in small cities, even within industry. This paper uses data on the occupational mix at establishments to test whether skill intensity is greater in large cities. Establishments in metropolitan areas with population above two million use a more skill intensive mix of workers than comparable establishments in metropolitan areas with population below one million. The differences in skill intensity are not the same in all industries; establishments in relatively skill intensive industries are even more skill intensive in large MSAs. These results support theories that suggest that the productivity gains from agglomeration are larger for skilled labor than unskilled labor.
The role of response processes in the formation of cross-modality assimilation effects!

The enhanced judgments of intensity of soft tones judged along with a series of bright lights (assimilation effect) was found to be dependent on the fact that the lights were judged coincidently. This dependence was not observed in a parallel investigation of contrast effects in the judgments of tones alone. Both the form of the assimilation effect and its specific dependence on judging both stimulus modalities argues against a sensory explanation. Instead, it is argued that this cross-modality assimilation effect represents a resolution of the specific difficulties involved in judging two qualitatively different modalities on one judgment scale
Intersection mappings for stereo vision

Stereo vision triangulation methods are used for three-dimensional measurements in conjunction with robot guidance and machine inspection applications. Understanding the computational geometry associated with stereo imaging, gives insight into the accuracy that can be obtained and into the surface types best inspected by such systems. The purpose of this paper is to discuss the shape of the triangulation space arising from stereo imaging for flexible stereo camera configurations. It is shown that the points of intersecting views arising from a stereo pinhole configuration form conic sections, which are a function of the disparity between the pixels in the two images. The significance of this work is that it provides a basis for improved quantitative and qualitative understanding of stereo vision.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Carbamazepine (Tegretol) as an anticonvulsant. A controlled double-blind comparison with diphenylhydantoin (Dilantin).

A large double blind crossover study of carbamazepine (CBZ) in comparison to diphenylhydantoin (DPH) is underway, and the results are presented for the first 20 patients to complete the protocol. The importance of preparatory steps is outlined – beginning with the gathering of preliminary kinetic data about half-life and peak-time in epileptic patients. A detailed pilot study was performed with open administration of the agents and hospitalization during the crossover. Detailed blood level monitoring and dose-equivalence calculations lead to the design of blind crossover protocol from the pilot study. Of the 20 patients reported on at this point, 12 had fewer seizures on CBZ, but 4 of these preferred DPH because of the CBZ side effects. Of the 8 having fewer seizures on DPH, 3 preferred CBZ – leading to a final disposition of 11 on CBZ and 9 on DPH. Mean serum levels were 34.1 μg/ml for DPH and 10.6 μg/ml for CBZ. The patients having fewer seizures on DPH had higher serum DPH levels than those doing better on CBZ, but the opposite was found for the CBZ levels. The implications of this difference are discussed. Over all, DPH and CBZ are effective anticonvulsants of the same general magnitude, but individual patient responses to effects and side-effects will influence their usefulness in any given case.
Interim analyses based on median survival times

SUMMARY For a typical two-arm survival study, analyses are usually performed periodically to evaluate, for example, the treatment difference. In this paper, we propose to use differences or ratios of estimated median survival times repeatedly during a study to evaluate the relative merit of two treatment groups. This new procedure provides quantitative assessments of the treatment difference and is completely model-free. Our method is illustrated with a recent AIDS clinical study which evaluates the efficacy of a reduced dose of AZT.
Symbiotic mutants of rhizobium meliloti that uncouple plant from bacterial differentiation

Spontaneous mutants at a new symbiotic locus in Rhizobium meliloti SU47 are resistant to several phages and are conditionally insensitive to a monoclonal antibody to the bacterial surface, apparently because they are deficient in a wild-type exopolysaccharide. On alfalfa, the mutants do not curl root hairs, but penetrate the epidermis directly, forming nodules that contain no visible infection threads or "bacteroids," have a few bacteria in superficial intercellular spaces only and not within the nodule cells, and fail to fix nitrogen (Fix-). Evidently, infection threads are not essential for cell proliferation and nodule formation, which are here induced by a bacterial signal at a distance and uncoupled from the bacterial differentiation that normally goes on as well.
Treatment of nephrogenic diabetes insipidus with prostaglandin synthesis inhibitors

The antidiuretic effect of two prostaglandin synthetase inhibitors, ibuproten (25 mg/kg/day) and indomethacin (2 mg/kg/day), was studied in patients aged 8 to 18 years with hereditary nephrogenic diabetes insipidus. Ibuprofen (studied in five patients) did not have demonstrable effects on urine volume, free water clearance, or osmolar clearance, but fractional excretion of sodium ecreased from a mean of 0.38% to 0.19% (P
Democracies Really Are More Pacific (in General): Reexamining Regime Type and War Involvement

Current consensus in the field of democratic peace research holds that democratic states go to war in general no less than nondemocratic states. The author challenges this consensus by reevaluating...