cssi/SciSciGPT-SciSciNet huggingface dataset:
Developing and Assessing Educational Games to Enhance Cyber Security Learning in Computer Science

Cyber security is a critical field in Computer Science education today. We need to prepare students for the increasing security challenges they will face in the future. The workforce also needs to have additional cyber security skills to best protect the interests of the nation. Motivating and engaging more students in this field is an important step to meet the needs of future workforce. Games have been successfully used in many areas of education, including Computer Science, to engage students in learning. They provide educational, immersive experiences, which could help underrepresented students gain the confidence to pursue a career or further study in the cyber security field while also inspiring others. The poster will present the three-year project that aims to develop and assess three educational games with in-game assessments to effectively teach cyber security concepts (Access Control, LAN Vulnerabilities and Buffer Overflow). These games will be designed with different levels of difficulty to target students from freshmen to seniors and integrated into the existing computer science curriculum at Winston-Salem State University and North Carolina A&T State University to benefit a wide range of students. In addition, all these games will be portable, self-contained and available for download from the project website.
Nanoscale MnO2 cathodes for Li-ion batteries: effect of thermal and mechanical processing

Abstract This study investigates the effect of thermal and mechanical processing of MnO2 nanoparticle cathodes on the electrochemical performance, ion intercalation mechanism and structural changes upon cycling. Thermal processing at different temperatures is utilized to tune the sub-nanoparticle polymorph composition, while mechanical processing (high energy ball-milling) is used to change the particle size and create a better contact between active material and conductive graphite additive. The combination of thermal and mechanical processing is also investigated for possible synergistic effects. The structural changes due to processing suggest that thermal treatment of the MnO2 nanoparticles at 400 °C forms a high concentration of pyrolusite domains (1 × 1 channels) leading to improved reversibility of lithium intercalation/de-intercalation and capacity retention. It is also found that ball-milling for a short time (20 min) leads to some amorphization and decrease of the crystallite sizes resulting in improved capacity. The structural changes and ion intercalation mechanism of the pristine and processed electrode materials during cycling are investigated by ex situ synchrotron x-ray diffraction (XRD) and ex situ and in situ x-ray absorption near edge structure (XANES) studies.
Vecchia–Laplace approximations of generalized Gaussian processes for big non-Gaussian spatial data

Abstract Generalized Gaussian processes (GGPs) are highly flexible models that combine latent GPs with potentially non-Gaussian likelihoods from the exponential family. GGPs can be used in a variety of settings, including GP classification, nonparametric count regression, modeling non-Gaussian spatial data, and analyzing point patterns. However, inference for GGPs can be analytically intractable, and large datasets pose computational challenges due to the inversion of the GP covariance matrix. A Vecchia–Laplace approximation for GGPs is proposed, which combines a Laplace approximation to the non-Gaussian likelihood with a computationally efficient Vecchia approximation to the GP, resulting in simple, general, scalable, and accurate methodology. Numerical studies and comparisons on simulated and real spatial data are provided. The methods are implemented in a freely available R package.
Evaluation of Perirenal Anatomic Landmarks on Computed Tomography to Reduce the Risk of Thoracic Complications During Supracostal Percutaneous Nephrolithotomy.

Introduction: Supracostal access for percutaneous nephrolithotomy (PNL) has a known increased risk for thoracic complications (TCs). In this study, we perform a radiological review of preoperative ...
Assessment of macrovascular and microvascular function in aging males.

NEW & NOTEWORTHY: Microvessel endothelial function assessed via finger plethysmography may not reflect age-associated reductions in large artery endothelial function assessed via brachial artery fl...
Comparison of Building Adaptation Projects and Design for Adaptability Strategies

Abstract The primary goal of this paper was to answer the question: Do empirical data from real-world projects align with Design for Adaptability (DfA) strategies reported in the literature? The da...
Comparative Spatial Segregation Analytics

Comparative segregation analysis holds the potential to provide rich insights into urban socio-spatial dynamics. However, comparisons of the levels of segregation between two, or more, cities at the same point in time can be complicated by different spatial contexts as well as ethnic, racial, and class distributions. The extent to which differences in segregation between two cities is due to differences in spatial structure or to differences in composition remains an open question. This paper develops a framework to disentangle the contributions of spatial structure and composition in carrying out comparative segregation analysis. The approach uses spatially explicit counterfactuals embedded in a Shapley decomposition. We illustrate this framework in a case study of the 50 largest metropolitan statistical areas in the U.S.
Implementation Process and Evolution of a Laparotomy-Assisted 2-Port Fetoscopic Spina Bifida Closure Program.

Introduction Prenatal closure of open spina bifida via open fetal surgery improves neurologic outcomes for infants in selected pregnancies. Fetoscopic techniques that are minimally invasive to the uterus aim to provide equivalent fetal benefits while minimizing maternal morbidities, but the optimal technique is undetermined. We describe the development, evolution, and feasibility of the laparotomy-assisted 2-port fetoscopic technique for prenatal closure of fetal spina bifida in a newly established program. Methods We conducted a retrospective cohort study of women consented for laparotomy-assisted fetoscopic closure of isolated fetal spina bifida. Inclusion and exclusion criteria followed the Management of Myelomeningocele Study (MOMS). Team preparation involved observation at the originating center, protocol development, ancillary staff training, and surgical rehearsal using patient-matched models through simulation prior to program implementation. The primary outcome was the ability to complete the repair fetoscopically. Secondary maternal and fetal outcomes to assess performance of the technique were collected prospectively. Results Of 57 women screened, 19 (33%) consented for laparotomy-assisted 2-port fetoscopy between February 2017 and December 2019. Fetoscopic closure was completed in 84% (16/19) cases. Over time, the technique was modified from a single- to a multilayer closure. In utero hindbrain herniation improved in 86% (12/14) of undelivered patients at 6 weeks postoperatively. Spontaneous rupture of membranes occurred in 31% (5/16) of fetoscopic cases. For completed cases, median gestational age at birth was 37 (range 27-39.6) weeks and 50% (8/16) of women delivered at term. Vaginal birth was achieved in 56% (9/16) of patients. One newborn had a cerebrospinal fluid leak that required postnatal surgical repair. Conclusion Implementation of a laparotomy-assisted 2-port fetoscopic spina bifida closure program through rigorous preparation and multispecialty team training may accelerate the learning curve and demonstrates favorable obstetric and perinatal outcomes.
Prospective Associations of Early Pregnancy Metal Mixtures with Mitochondria DNA Copy Number and Telomere Length in Maternal and Cord Blood.

Background: Metal exposure during pregnancy influences maternal and child health. Oxidative stress and inflammation may mediate adverse effects of heavy metals, whereas essential metals may act as ...
Comparison of graft-reinforced repairs and suture repair using a novel biomechanical test.

The aim of this study was to determine the feasibility of a novel biomechanical test for evaluating mesh-reinforced repair compared to suture-reinforced repair using an animal model. We hypothesized that the fatigue life of a mesh reinforced repair would be greater than that of xenograft reinforced repair and suture-only repair. Wistar rats were randomly assigned to undergo a ventral hernia repair using sutures or one of the three mesh materials representative of incorporation, encapsulation and resorption host responses (Gynemesh®, Pelvisoft® and Surgisis®, respectively). All surviving animals were killed at 90 days and specimens containing the prosthesis–tissue interface were exposed to cyclic forces. The number of cycles to failure (fatigue life) was compared between groups using a Cox regression model. Of 40 randomly assigned animals, 11 died before 90 days. After randomizing an additional 5 rats, a total of 34 rats were killed at 90 days. The proportions of specimens that failed before 10,000 cycles were 25 % (2/8), 50 % (4/8), 62.5 % (5/8) and 70 % (7/10) in the Gynemesh, Surgisis, Pelvisoft, and suture control groups, respectively. In addition, the median number of cycles to failure was >10,000 in the Gynemesh group, >6,923 in the Surgisis group, 1133 in the Pelvisoft group and 741 in the control group. After adjustment for cross-sectional area, the risk of failure in the suture control group was higher than in all of the reinforced repair groups combined with an adjusted hazard ratio of 2.58 (95 % CI 0.96 – 6.97), and was statistically significantly higher than in the Gynemesh group with an adjusted hazard ratio of 6.67 (95 % CI 1.30 – 34.48). We present a novel biomechanical test that can be used to compare mesh materials in an animal model prior to use in humans. In this animal model, after adjusting for cross-sectional area, suture reinforced repair has a higher risk of failure than graft reinforced repair.
Formalizing Database Recovery.

Failure resilience is an essential requirement for database systems, yet there has been little e ort to specify and verify techniques for failure recovery formally. The desire to improve performance has resulted in algorithms of considerable sophistication, yet understood by few and prone to errors. In this paper, we illustrate how the methodology of Gurevich Abstract State Machines can elucidate recovery and provide formal rigor to the design of a recovery algorithm. In a series of re nements, we model a recovery algorithm at several levels of abstraction, verifying the correctness of each model. This work suggests that our approach can be applied to more advanced recovery mechanisms.
Glycosphingolipids in cultured human skin fibroblasts. II. Characterization and metabolism in fibroblasts from patients with inborn errors of glycosphingolipid and mucopolysaccharide metabolism

Abstract Fibroblasts cultured from skin biopsies obtained from patients with inherited storage diseases exhibited the specific lysosomal hydrolase deficiency found in the patient's tissues. Combined thin layer and gas liquid chromatography of the glycosphingolipids isolated from such fibroblasts showed variations in the concentration of the seven glycosphingolipids found in normal fibroblasts, GL-1a, GL-1b, GL-2a, GL-3, GL-4, Gm3, and Gd3. In three diseases in which visceral accumulation of glycosphingolipid has been demonstrated, namely, Fabry's disease, lactosylceramidosis and Gaucher's disease, two to 4-fold elevations of the glycosphingolipids, GL-3, GL-2a, and GL-1a, respectively, were found in the cultured skin fibroblasts. Tracer studies with d-[U-14C]glucose demonstrated negligible catabolism of GL-3 in Fabry cells and GL-1a in Gaucher cells. The rate of synthesis and degradation of other glycosphingolipids appeared normal with the exception of GL-2a which was virtually absent from Fabry fibroblasts. Although the enzyme deficiencies characteristic of ganglioside storage (neuronal) diseases could be demonstrated in fibroblasts, Gm1 ganglioside could not be detected in two strains of fibroblasts from patients with Gm1-gangliosidosis type I. However, in two strains of fibroblasts from patients with Gm2-gangliosidosis type I (Tay-Sachs disease) there was some evidence for the presence of Gm2 and its asialo derivative. Fibroblasts from patients with inherited lipidoses which primarily affect the myelin sheath, such as globoid cell leukodystrophy and metachromatic leukodystrophy did not accumulate cerebroside (GL-1b) or sulfatide (GL-1bS) despite the fact that the specific enzyme deficiency could be readily demonstrated. The addition of large amounts of sulfatide to the medium caused storage of sulfatide in normal skin fibroblasts which was rapidly metabolized when the cells were returned to normal medium. In contrast, fibroblasts from patients with metachromatic leukodystrophy (with deficient arylsulfatase A activity) ingest but do not metabolize exogenous sulfatide. A marked abnormality of Gm3 and Gd3 catabolism was demonstrated in fibroblasts from three patients with I-cell disease, an unusual genetic disorder in which there is a generalized lysosomal hydrolase deficiency.
A study of the hatching process in aquatic invertebrates: XX. The blue crab,Callinectes sapidus, Rathbun, XXI. The nemertean,Carcinonemertes carcinophila (Kölliker)

Hatching mechanisms were investigated in the blue crab,Callinectes sapidus, and in its egg- and gill-parasite, the nemerteanCarcinonemertes carcinophila, collected in the southern Chesapeake Bay area.
Design and evaluation of interaction models for multi-touch mice

Adding multi-touch sensing to the surface of a mouse has the potential to substantially increase the number of interactions available to the user. However, harnessing this increased bandwidth is challenging, since the user must perform multi-touch interactions while holding the device and using it as a regular mouse. In this paper we describe the design challenges and formalize the design space of multi-touch mice interactions. From our design space categories we synthesize four interaction models which enable the use of both multi-touch and mouse interactions on the same device. We describe the results of a controlled user experiment evaluating the performance of these models in a 2D spatial manipulation task typical of touch-based interfaces and compare them to interacting directly on a multi-touch screen and with a regular mouse. We observed that our multi-touch mouse interactions were overall slower than the chosen baselines; however, techniques providing a single focus of interaction and explicit touch activation yielded better performance and higher preferences from our participants. Our results expose the difficulties in designing multi-touch mice interactions and define the problem space for future research in making these devices effective.
A new prognostic score for patients with lower-risk myelodysplastic syndrome (MDS) allows the identification of a subset of patients with poor prognosis

7076 Background: Current prognostic models of MDS do not allow the identification of patients (pts) with lower risk disease and poor prognosis. Methods: We evaluated the characteristics of 898 pts ...
Antimagic Labelings of Weighted and Oriented Graphs

A graph $G$ is $k$-$weighted-list-antimagic$ if for any vertex weighting $\omega\colon V(G)\to\mathbb{R}$ and any list assignment $L\colon E(G)\to2^{\mathbb{R}}$ with $|L(e)|\geq |E(G)|+k$ there exists an edge labeling $f$ such that $f(e)\in L(e)$ for all $e\in E(G)$, labels of edges are pairwise distinct, and the sum of the labels on edges incident to a vertex plus the weight of that vertex is distinct from the sum at every other vertex. In this paper we prove that every graph on $n$ vertices having no $K_1$ or $K_2$ component is $\lfloor{\frac{4n}{3}}\rfloor$-weighted-list-antimagic. An oriented graph $G$ is $k$-$oriented-antimagic$ if there exists an injective edge labeling from $E(G)$ into $\{1,\dotsc,|E(G)|+k\}$ such that the sum of the labels on edges incident to and oriented toward a vertex minus the sum of the labels on edges incident to and oriented away from that vertex is distinct from the difference of sums at every other vertex. We prove that every graph on $n$ vertices with no $K_1$ component admits an orientation that is $\lfloor{\frac{2n}{3}}\rfloor$-oriented-antimagic.
Effects of dietary cholesterol, type of fat, and sex on bile lipid composition of adult baboons

We measured the effects of dietary cholesterol (0.24 vs 0.0024 mg/kJ), type of dietary fat [saturated, a ratio of polyunsaturated to saturated fatty acids (P:S) of 0.37, vs unsaturated (P:S of 2.2)], and sex on biliary lipid and bile acid conjugate composition of 80 adult pedigreed baboons. From these data we calculated the bile cholesterol saturation index and the bile acid hydrophobicity index. Dietary cholesterol significantly increased the bile cholesterol concentration by 25% and the bile cholesterol saturation index by 15%, but did not significantly affect the bile acid conjugate composition or the bile acid hydrophobicity index. Diets high in saturated fatty acid compared with unsaturated fatty acid significantly decreased the bile cholesterol concentrations by 26% and the saturation index by 23%. Saturated fatty acid also decreased the proportion of hydrophobic bile acids and lowered the bile hydrophobicity index. Male baboons had a higher cholesterol saturation index and a lower hydrophobicity index than females. Dietary cholesterol and saturated fatty acid independently influence the bile lipid composition and the cholesterol saturation index.
Positive crossmatch kidney transplant recipients treated with eculizumab: outcomes beyond 1 year

This study examined outcomes beyond 1 year in eculizumab-treated (EC) positive crossmatch kidney transplants (+XMKTx) compared to a historical control group. +XMKTx received desensitization with either plasma exchange (PE) alone (N = 48) or PE and EC (N = 30). EC, given for at least 1 month, was continued in the setting of persistently high DSA (B flow cytometric crossmatch [BFXM] >200) including: 4 weeks (n = 14); 9 weeks (n = 6), 6 months (n = 2), and 12 months (n = 8). All patients had at least 2 years follow-up. The incidence of acute clinical ABMR was lower in the EC group than controls (6.7% vs. 43.8% p 0, 26.7% versus 31.9% (p = 0.62), ptc score ≥ 2, 60.0% versus 60.0% (p = 1.00), or C4d + , 33.8% versus 13.5% (p = 0.08). A persistently high BFXM in EC-treated patients was associated with cg score >0 at 1 year, while EC appeared to protect against cg if the BFXM remained low. We conclude that despite decreasing acute clinical ABMR rates, EC treatment does not prevent chronic ABMR in recipients with persistently high BFXM after +XMKTx.
A Hair & a Fungus: Showing Kids the Size of a Microbe.

A simple method is presented to show kids the size of a microbe – a fungus hypha – compared to a human hair. Common household items are used to make sterile medium on a stove or hotplate, which is dispensed in the cells of a weekly plastic pill box. Mold fungi can be easily and safely grown on the medium from the classroom environment. A microscope capable of 200–400× is necessary. Students can use a hair from their own head to view a fungus and a hair side-by-side on the same slide. They will see that a microscopic fungus hypha is 20–50× smaller in diameter than a hair. Older students will also learn that microbes are measured in micrometers, that fungi are ubiquitous, and that decay is an inevitable part of Earth’s processes.
New Families and New Members of Integer Sequence Based Coding Methods

This paper presents Integer sequences that have the property of being additively and/or multiplicatively complete, Zekendorf, and unique Zekendorf. In addition, a generalized Elias coding scheme is developed. Features of Zekendorf sequence based and generalized Elias coding compression methods including compression rate, universality, asymptotic optimality, and coding complexity are analyzed.
Diet and Racial Temperament

Resume On croit assez generalement qu 'on peut produire des differences de race par l 'influence de la nourriture, par exemple, que les races qui mangent la viande sont turbulentes, bellicoses et inquietes tandis que les races vegetariennes sont paisibles, calmes et d 'une douce humeur. Le probleme est complique par des questions telles que beaucoup de proteine et peu de proteine, proteine animale et proteine vegetale, la grande probabilite qu 'un regime vegetarien ne sera pas suffisant et les effets possibles des purines dans la viande. L 'idee existe depuis beaucoup d 'annees qu 'un regime carnivore rendra les animaux feroces et sauvages mais qu 'un regime vegetarien les rendra dociles. Bien que les proteines semblent avoir quelque relation au niveau du metabolisme fondamental, il n 'est pas clair que cela soit necessairement responsable de la vigueur de race. Les etudes de l 'activite des rats et des souris indiquent definitivement l 'heredite comme facteur. Vu ce travail experimental il est possible q...
A Three-Aircraft Intercomparison of Two Types of Air Motion Measurement Systems

Abstract We present procedures to evaluate air motion measurements on two or more aircraft by flying them in formation at a known lateral displacement. The analysis is applied to two formation flights involving three aircraft—the NCAR Electra, Sabreliner and King Air—in a clear convective boundary layer to compare two types of air motion sensing probes mounted on different aircraft. The lateral separation between the Electra in the center, and the other two aircraft was ≈30 m. One sensing system utilized constrained vanes and the other differential pressure measurements across ports on a nose radome to obtain the two airflow angles that are used to calculate the transverse air velocity components. Both systems used a Pitot-static pressure difference for obtaining the longitudinal velocity component. We compare differences in means and variances, spectra and cospectra, and spatial coherences between the same velocity components measured on the different aircraft. The differences are, in most cases, compara...
Testosterone stimulation of the oviduct in vitamin-deficient chicks.

ASTUDY of the inter-relationships of vitamin deficiencies, inanition, and estrogen stimulation of the chick oviduct has been reported in a previous paper (Kline and Dorfman, 1950, a). Since it was shown that animals suffering from inanition manifest a nonspecific resistance to hormonal stimulation, oviduct responses to estrogen in vitamin-deficient animals were therefore interpreted by comparison to the response of inanition controls in order to correct for the inanition which inevitably accompanies vitamin-deficiency states. Of the four vitamin-deficiency states investigated, only that of a deficiency of pteroylglutamic acid (PGA) resulted in a severe limitation of oviduct response to estrogen stimulation. This confirmed the findings of Hertz (1945). Since androgens are also capable of stimulating growth of the chick oviduct, a similar investigation of the inter-relationships of vitamin deficiencies, inanition and oviduct response to testosterone propionate has been made. The results indicate that oviduc...
Comparison of Light Compensation Points for Two Submersed Macrophytes

ABSTRACT A laboratory growth experiment indicated that the ribbon-leaved Potamogeton gramineus L. had a lower light compensation point for growth (LCP) than the thread-leaved P. pectinatus L. LCP and 95 % confidence intervals (CI) were 0.86 M m−2 day−1 (95% CI, −0.006 to 1.540) and 3.87 M m−2 day−1 (95% CI, 3.12 to 4.63), respectively. When germinated propagules of each species were planted in a P. gramineus stand in the Byrnes Canal, P. pectinatus exhibited lower survival than similar plants placed in the canal but outside the P. gramineus bed. Mean plant weight for P. pectinatus grown within the plant bed was less than 10 % of that for plants grown outside the P. gramineus bed. Neither survival nor mean dry weight of P. gramineus planted at the same sites differed among the sites. Estimates of light levels in the P. gramineus bed indicated that shading by P. gramineus reduced light to levels at or below the LCP for P. pectinatus but above the LCP for P. gramineus. These results suggest that P. pectinatu...
Myocardial Revascularization in Women

Abstract During the period January, 1970, through June, 1977, 1,541 patients underwent coronary artery bypass grafting; 241 of them were women (15.6%). Operative mortality rates for the entire study were 2.4% in men and 3.7% in women, but they showed a marked decline in women during 1975 to mid-1977, with only 2 deaths in 140 patients (1.4%). Women comprised a larger percentage of patients (16.7%) in these later years. Women were slightly older, received fewer grafts, had better preservation of ventricular function on preoperative studies, and had more severe anginal symptoms than men. Patency rates were significantly lower in women at 1 month, 1 year, and 3 years. Five-year survival was not significantly different between women (88.3%) and men (93.5%). Many of these findings may be explained on the basis of women having smaller coronary arteries than men. These favorable results differ from earlier reports of higher mortality rates in women and indicate that myocardial revascularization should not be withheld from female patients.
Essential Requirements for Robust Signaling in Hfq Dependent Small RNA Networks

Bacteria possess networks of small RNAs (sRNAs) that are important for modulating gene expression. At the center of many of these sRNA networks is the Hfq protein. Hfq's role is to quickly match cognate sRNAs and target mRNAs from among a large number of possible combinations and anneal them to form duplexes. Here we show using a kinetic model that Hfq can efficiently and robustly achieve this difficult task by minimizing the sequestration of sRNAs and target mRNAs in Hfq complexes. This sequestration can be reduced by two non-mutually exclusive kinetic mechanisms. The first mechanism involves heterotropic cooperativity (where sRNA and target mRNA binding to Hfq is influenced by other RNAs bound to Hfq); this cooperativity can selectively decrease singly-bound Hfq complexes and ternary complexes with non-cognate sRNA-target mRNA pairs while increasing cognate ternary complexes. The second mechanism relies on frequent RNA dissociation enabling the rapid cycling of sRNAs and target mRNAs among different Hfq complexes; this increases the probability the cognate ternary complex forms before the sRNAs and target mRNAs degrade. We further demonstrate that the performance of sRNAs in isolation is not predictive of their performance within a network. These findings highlight the importance of experimentally characterizing duplex formation in physiologically relevant contexts with multiple RNAs competing for Hfq. The model will provide a valuable framework for guiding and interpreting these experiments.
Cortical scalloping and cortical penetration by small eccentric chondroid lesions in the long tubular bones: not a sign of malignancy?

The objective of this study was to evaluate by cross-sectional imaging the prevalence and degree of cortical scalloping by small eccentric chondromas correlated with histologic diagnosis and patient history. From 122 patients with histologically proven enchondromas and two patients without histology but with radiologic and clinical follow-up, 11 patients with small, eccentrically located chondromas in the long bones had cross-sectional imaging available. The lesions were evaluated for location, size, presence, and degree of cortical scalloping. The patient’s medical charts and microscope slides were reviewed for relevant clinical history, clinical management, and histology. The chondromas ranged in size from 1.6 to 3.8 cm (mean 2.3 cm). Two lesions were located in the proximal femoral diaphysis, two in the distal femoral diaphysis, six in the distal femoral metaphysis, and one in the proximal tibial epimetaphysis. The lesions were curetted due to diagnostic uncertainty, continued pain, marked radiologic cortical penetration, or due to patient insistence on biopsy. All 11 lesions were benign, nine histologically, and two by stability over 4 and 7 years. The prevalence of cortical scalloping among eccentric chondromas was 100%. Cortical scalloping or occupancy ranged from 50 to 100% (mean 75%). All small eccentric chondromas in this study were associated with an appearance of cortical scalloping of varying degree. All curetted lesions were histologically bland without nuclear atypia. Based on the benign histology of nine lesions and lack of growth of two lesions over several years, the degree of cortical scalloping is felt to be a result of lesion location within the endosteum rather than biological activity or malignancy.
Enhanced measurement-based dynamic equivalence using coherency identification

Power system dynamic simulation demands substantial computation due to extensive interconnection among power systems. Traditionally, the computational burden has been reduced by using dynamic equivalent methodologies, such as modal, coherency and measurement-based. Measurement-based method replaces an external system with a simple equivalent and estimates its parameters through optimization method with measurement. However, the conventional method does not clearly present the model structure for the external equivalent. This ambiguity, then, may lead to poor performance of the equivalent. The proposed method uses generator equivalent model and shows how to choose a proper number of generators for the equivalent model structure using coherency concept. The approach preserves relevant modes from the external and thus enhances the simulation performance of the dynamic equivalent. Test results of a simple power system are presented and show a high level of accuracy of the proposed method.
Epizoochorous dispersal by bats in French Guiana

In neotropical forests many species of plant depend on animals for pollination and seed dispersal and it has been well documented that bats play an essential role in dispersal of many flowering plants (Gardner 1977). Bats are responsible for colonization of plants into forest gaps because they often disperse the seeds of plants adapted for growth in disturbed areas. Species of Cecropia, Piper, Solanum and Vismia are especially important pioneer plants, and bats play a critical role in the dispersal of these secondary woody species into both secondary and primary forests, and into the seed bank (de Foresta et al. 1984, Lobova et al. 2003). The database of Mori & Blanchard (URL: http://www. botanypages.org/) includes 400 neotropical plant species reported to be bat dispersed. Many of these records concern endozoochorous seed dispersal because it is the most easily studied. In this type of dispersal, the bat consumes the fruit or parts of the infructescence, digests the fleshy pericarp, perianth or receptacle (syconium of Ficus), and defecates the seeds or fruits in flight or at a roost. In addition, there are frequent reports of bats carrying away fruits or seeds in their mouths for later consumption of the fleshy pericarp or edible seed parts (e.g. arils and sarcotestas) at their roosts (Charles-Dominique 19 8 6, 199 3; Charles-Dominique & Cooper 19 8 6). In this exozoochorous type of dispersal, the diaspores are usually dropped under the roosts or by accident during flight. Epizoochorous dispersal, in which diaspores are attached to the fur of an animal by adhesion, has not yet been reported for bats. This type of dispersal, if facilitated by barbs or hooks, has been called epizoochory by burrs (Sorensen 1986) and is relatively infrequent, especially in lowland tropical forests. For example, only 1.5 % of the flowering plants in the flora of central French Guiana
Resonance behavior of electron scattering from nitrogen molecules adsorbed on metallic surfaces

Abstract We use the coupled angular modes theory of electron scattering from molecules to identify the important role played by substrate multiple scattering in determining the lifetime of transient negative ions in adsorbed molecules. For the 2 Π g negative ion resonance in N 2 , we demonstrate the phenomenon of complete resonance quenching which occurs when the resonance energy is such that the probe electron is strongly reflected from the substrate. This situation may occur when the resonance energy lies in a band-gap of the unoccupied states of a metallic substrate. It is proposed that the simple resonance energy shift and lifetime reduction observed in previous experimental and theoretical studies of resonance electron scattering from adsorbates is by no means a universal phenomenon. The importance of the unoccupied metallic band structure of the substrate in determining the properties of negative ions in adsorbed molecules is discussed.
DISSOCIABILITY OF DEVELOPMENTAL PROCESSES IN THE MORPHOGENESIS OF THE EAR IN AMBYSTOMA, AS REVEALED BY X-RAY DAMAGE.

Eggs of Ambystoma maculatum from the same clutch were separated at Harrison's stage eight into three groups and maintained at 8°, 14° and 20°C, respectively, until stage 28. At these three temperatures the respective number of hours between stages eight and 28 were 291, 171, 99. Half of each group was then x-irradiated with 600 r and the right ear vesicle substituted for that of the non-irradiated complement. Subsequent development of the irradiated grafts, all reared at 20°C, was compared among the groups. Within the range of temperatures employed, hypothermia alone has no effect upon final ear development; every left ear in all groups developed normally. Development of irradiated grafts in the 8° group is decidedly more abnormal than in either 14° or 20° groups. With the exception of the VIIIth ganglion, development of the grafts in 14° and 20° groups is approximately the same. On the basis of 8° = 1, average developmental ratings for the three groups are approximately as follows: size — 1:2:2. differentiation — 1:2:2. ganglion — 1:2:5. The data demonstrate that the chronologically older ear is more radiosensitive than the younger, despite morphological parity among groups at time of irradiation. This suggests that prolonged hypothermia may dissociate in time the invisible or biochemical processes of development from the purely morphological; the pace of the former is less retarded than the latter.
Joint Doppler and polarization characterization of moving targets

In through-the-wall imaging radar systems, the synthesized images may not provide sufficient range and cross-range resolution for visual classification and identification of the targets. Target movement and target Doppler characteristics can be used to combat resolution limitations and improve object discrimination. However, slowly moving targets and targets moving perpendicular to the incident waves render target motion ineffective in high-resolution imaging. We utilize the target's polarization properties and introduce time-varying polarization signature estimation based on polarization time-frequency distribution.
Large scale simulations of the thermodynamics of quantum chromodynamics

Hybrid stochastic and microcanonical algorithms are applied to simulate SU(3) lattice gauge theory with four species of dynamical, light quarks. Lattices of size 6×103 and bare quark masses ranging from m=0.250 down to 0.050 (in lattice units) are employed to study the character of the transition from hadronic matter to the quark-gluon plasma. Metasbability studies suggest that as the bare quark mass decreases the transition changes from strongly first order at m=0.250 to an abrupt crossover at m=0.050. The temperature of the crossover region is found to be T/ΛMS=2.14±0.10 and should be accessible to planned heavy ion experiments.
Speeding up N-body Calculations on Machines without Hardware Square Root

The most time consuming part of an N-body simulation is computing the components of the accelerations of the particles. On most machines the slowest part of computing the acceleration is in evaluating $r^{-3/2}$, which is especially true on machines that do the square root in software. This note shows how to cut the time for this part of the calculation by a factor of 3 or more using standard Fortran.
Characteristics that Influence Individuals' Preferences for Levels of Complexity in Interior Design Furnishings

The purpose of this research was to examine whether gender as well as skills in math, art, and mental rotation is related to aesthetic preferences for interior design furnishings. Existing research determined that individuals differ in their aesthetic preferences and can be grouped as either having preference for complex, simple, a mixture of complex and simple, or no preference. One hundred and twenty-eight subjects (49 males, 79 females) were administered an interior design preference test, a mental rotation test, and a questionnaire about previous math and art grades and skill level. Results indicated that complex preferrers were more frequently males and exhibited strong skills in mental rotation, art/drafting, and art history. Simple preferrers demonstrated weak skills in mental rotation, art/drafting, and art history and were more frequently female. Those with no preference were more frequently females with strong skills in math and art/drafting. The mixed-preference group was represented equally by males and females, exhibiting strong math skills, but weak skills in mental rotation, art/drafting, and art history.
Voltage regulation in medium voltage DC systems

We describe a new method of operating MVDC power systems that is characterized by two aspects: 1) operation of main power sources in current-controlled mode, and voltage regulation via a (relatively) low-power voltage-source converter sourced from a small energy storage system (voltage regulator energy storage system or VRESS). In comparison to the bulk energy storage system, the VRESS is more agile - smaller, faster, lower power. This new voltage regulation scheme reduces capacitance on the dc bus, with the aim of reducing peak discharge currents during faults. Sizing and rating of the VRESS must consider power ramp rates of both the generating units and the loads. A notional system based on the proposed method is designed, implemented in simulation, and evaluated, with the results showing good efficacy in both steady state and dynamic conditions.
Hexamethyldisiloxane as a mobile phase component for normal phase liquid chromatography

Hexamethyldisiloxane (HMDX) has been evaluated as a modifier solvent for the normal phase separation of substituted naphthalene componds as well as aromatics such as nitrobenzene, acetophenone, benzonitrile, and aniline. It is found to be a weaker eluting solvent than n-butyl ether and other commonly used normal phase solvents filling a niche in the eluotropic series. HMDX exhibited an unusual retention factor (k′) profile as a function of mobile phase composition in hexane. In a range from 0 to 40 %, thek′ values remained quite constant with increasing HMDX composition. As the concentration of HMDX progressed to 100 %, thek′ values actually increased in a generally linear fashion. This trend ink′ is due to longer solute retention not just a change in the retention time of the unretained component. Although slight silanization of the silica column may occur with initial use of HMDX, retention of these analytes on a commerical C-1 silica column is much lower with no positivek′ slope with increasing HMDX. The chromatographic data provide evidence that HMDX is likely adsorbed to the silica surface and a solute partitioning mechanism may be operative.
Predation and bark beetle dynamics

Bark beetle populations may undergo dramatic fluctuations and are often important pests in coniferous forests. Their dynamics are thought to be primarily driven by factors affecting the resistance of the host tree to attack, i.e., bottom-up forces, while natural enemies are usually assigned a minor role in these systems. I present behavioral experiments that suggest that the clerid beetle Thanasimus dubius may be an important source of mortality for the bark beetle Dendroctonus frontalis during attack of the host tree, and determine the nature of the functional response of T. dubius under conditions close to natural. I also examine the numerical response of T. dubius to large-scale fluctuations in D. frontalis density, and the relationship between bark beetle population trends and predator density, and find that beetle populations tend to decline when predator densities are high. Combined with the effects of clerid larvae on bark beetle broods, these results suggest that top-down forces generated by natural enemies could also be an important component of bark beetle dynamics. The implications of these results for bark beetle dynamics are discussed in relation to the prolonged life-cycle of clerid beetles.
Nd-Sr-Pb systematics and age of the Kings River ophiolite, California: implications for depleted mantle evolution

Sm-Nd whole-rock and mineral data for the Kings River ophiolite define two isochrons of 485±21 Ma and 285±45 Ma age with e_Nd (483)= +10.7±0.5 and e_Nd (285)= +9.9±1.1, respectively. The 483 Ma isochron is defined by samples of the main igneous construct. Samples from crosscutting diabase dikes and flaser gabbro sheets within the peridotite unit yield the 285 Ma isochron. The 483 Ma data provide the first evidence of lower Paleozoic oceanic crust in the Sierran ophiolite belt. New U-Pb analyses of zircons from a plagiogranite lying on the 483 Ma Sm-Nd isochron yield upper and lower intercepts with the concordia of 430^(+200)_(−60) and 183±15 Ma. Published zircon ages have underestimated the primary age of the ophiolite by 200–300 m.y. due to the effects of polymetamorphism. The 483 Ma samples have initial ^(87)Sr/^(86)Sr=0.7023–0.7030, ^(206)Pb/^(204)Pb=17.14–17.82, ^(207)Pb/^(204)Pb=15.37–15.52, ^(208)Pb/^(204)Pb=36.80–37.38. The 285 Ma samples have similar initial 87Sr/86Sr, but more radiogenic Pb. The range in Sr and Pb compositions is probably due to introduction of radiogenic Sr and Pb during multiple post-emplacement metamorphic events. The high e Nd, low ^(87)Sr/^(86)Sr, ^(206)Pb/^(204)Pb, ^(207)Pb/^(204)Pb, ^(208)Pb/^(204)Pb of the least disturbed samples are clearly diagnostic of a midocean ridge origin for the 483 Ma portion of the ophiolite. Igneous activity at 285 Ma is thought to have occurred in an arc or back-arc setting, or perhaps along a leaky transform. The initial e_Nd (483)=+10.7 is indistinguishable from that of the similar age Trinity Peridotite (Jacobsen et al. 1984). This value is the highest yet reported for the Mesozoic or Paleozoic depleted mantle and requires either a mantle source that was depleted ∼ 850 m.y. earlier than average or a source more highly depleted than average. Alternatively, if such values were more typical of the early Paleozoic mantle than is currently thought, then there has been little evolution of the depleted mantle over the last ∼ 500 m.y. This requires that the modern mantle has been refluxed by material with low e_Nd, such as continental crust.
Phenotypic changes in MCF-7 cells during prolonged exposure to tamoxifen.

Abstract MCF-7 breast tumor cells form multicellular nodules (foci) over a confluent monolayer in an estradiol (E2)-dependent, antiestrogen-sensitive reaction. A cell line cloned from MCF-7 that displays these phenotypes was probed to determine the effects of long term exposure to tamoxifen on the growth of foci, estrogen receptor alpha (ERα) status, and gene responsiveness to E2. In one of two experiments, a heterogeneous cell population emerged (TMX2) that over-expressed estrogen receptor alpha wild type mRNA (ERα mRNA) (∼20-fold) missing exon 3 (ERΔ3 mRNA) and its corresponding protein (ERΔ3P). On a per mRNA to protein basis, ERΔ3P and wild-type ERα were equivalently expressed. Return of the TMX2 population to medium without tamoxifen eventually selected for a population that expressed predominately wild-type ERα, whereas TMX2 clones over expressing ERΔ3 mRNA and ERΔ3P retained this phenotype in tamoxifen-free media. In both experiments, expression of all ERα mRNAs and proteins declined to barely detectable levels during 6–12 months exposure, concomitant with a progressive increase in the ability of the cells to form foci independently of E2 or tamoxifen. Selection for these various populations suggests that tamoxifen can induce and/or support certain cellular changes that lead to altered ERα expression, E2-independent cell growth and resistance to antiestrogens.
Interaction of c-myc with transforming growth factor α and hepatocyte growth factor in hepatocarcinogenesis

Abstract Double transgenic mice bearing fusion genes consisting of mouse albumin enhancer/promoter-mouse c- myc cDNA and mouse metallothionein 1 promoter-human TGF- α cDNA were generated to investigate the interaction of these genes in hepatic oncogenesis and to provide a general paradigm for characterizing the interaction of nuclear oncogenes and growth factors in tumorigenesis. Coexpression of c- myc and TGF- α as transgenes in the mouse liver resulted in a tremendous acceleration of neoplastic development in this organ as compared to expression of either of these transgenes alone. The two distinct cellular reactions that occurred in the liver of the double transgenic mice prior to the appearance of liver tumors were dysplastic and apoptotic changes in the existing hepatocytes followed by emergence of multiple focal lesions composed of both hyperplastic and dysplastic cell populations. These observations suggest that the interaction of c- myc and TGF- α , during development of hepatic neoplasia contributes to the selection and expansion of the preneoplastic cell populations which consequently increases the probability of malignant conversion. These studies have now been extended to examine the interaction of hepatocyte growth factor (HGF) with c- myc during hepatocarcinogenesis in the transgenic mouse model. While sustained overexpression of c- myc in the liver leads to cancer, coexpression of HGF and c- myc in the liver delayed the appearance of preneoplastic lesions and prevented malignant conversion. Similarly, tumor promotion by phenobarbital was completely inhibited in the c- myc /HGF double transgenic mice whereas phenobarbital was an effective tumor promoter in the c- myc single transgenic mice. The results indicate that HGF may function as a tumor suppressor during early stages of liver carcinogenesis, and suggest the possibility of therapeutic application for this cytokine. Furthermore, we show for the first time that interaction of c- myc with HGF or TGF- α results in profoundly different outcomes of the neoplastic process in the liver.
The Importance of Wnt Signaling in Cardiovascular Development

Cardiac development is comprised of a series of morphological events tightly controlled both spatially and temporally. The molecular pathways controlling early cardiac differentiation are poorly understood, but Wnt signaling is emerging as a critical pathway for multiple aspects of early cardiovascular development. The Wnt pathway plays multiple roles in regulating cellular behavior including proliferation, differentiation, cell migration, and cell polarity. Recent data have demonstrated that Wnt activity is important for early precardiac mesoderm differentiation but must be inhibited in subsequent steps for cardiomyocyte differentiation to proceed. Given the important role that Wnt signaling plays in both the differentiation of cardiomyocytes from pluripotential stem cells and tissue regeneration in general, an increased understanding of this pathway is likely to enhance our knowledge about both cardiovascular development and reparative mechanisms.
Fram Strait sea ice outflow

We summarize 24 years of ice export estimates and examine, over a 9-year record, the associated variability in the time-varying upward-looking sonar (ULS) thickness distributions of the Fram Strait. A more thorough assessment of the PMW (passive microwave) ice motion with 5 years of synthetic aperture radar (SAR)observations shows the uncertainties to be consistent with that found by Kwok and Rothrock [1999], giving greater confidence to the record of ice flux calculations.