cssi/SciSciGPT-SciSciNet huggingface dataset:
Embryonic gene expression among pollutant resistant and sensitive Fundulus heteroclitus populations

Changes in gene expression, coupled with biochemical, physiological, and behavioral alterations, play a critical role in adaptation to environmental stress. Our goal was to explore ways natural populations may have adapted to local, polluted environments. We took advantage of natural populations of Fundulus heteroclitus, one of the few studied fish species in North America that has established resistant populations in highly contaminated urban estuaries. We analyzed morphology, physiology, and gene expression of developing F. heteroclitus embryos during late organogenesis (stage 31); these embryos were from both resistant and sensitive populations and were raised in a common, unpolluted environment. While cardiac heart rates show significant differences between embryos of parents from clean and heavily contaminated Superfund sites, time-to-stage, embryo morphology, and gene expression profile analyses do not differ significantly between untreated embryos from resistant and sensitive populations. Further evaluation that includes tissue-specific approaches in gene expression analysis and larger sample sizes may be necessary to highlight important phenotypes associated with mechanisms of sensitivity and resistance among natural F. heteroclitus embryo populations. Alternatively, population differences may be masked by developmental canalization, and biologically important differences between sensitive and resistant embryos may only manifest with exposure (e.g., be dependent on gene by environment interactions).
VIBRATION SUPPRESSION WITH RESETTABLE DEVICE

Novel low-power or semiactive devices are developed for vibration suppression applications. By manipulating the structural stiffness, the resisting forces generated by the devices are quite large and independent of velocity. Experimental results are presented to demonstrate the feasibility of the devices and to justify the main assumptions used. The critical design issue of device placement is addressed analytically and verified. While much of the development here applies to the case of variable stiffness devices, we focus on resettable devices in which the device behaves like a linear spring. However, at appropriate times, the effective unstretched length of the device is changed—or reset—to extract energy from the vibrating structure.
Antibody fragments in tumor pretargeting. Evaluation of biotinylated Fab' colocalization with recombinant streptavidin and avidin

An evaluation of the use of a biotinylated monoclonal antibody Fab‘ fragment in tumor pretargeting was conducted. As a model system, tumor colocalization of avidin or recombinant streptavidin (r-st...
Factors Associated with More Positive Body Self-Concepts in Preschool Children

Summary A national stratified sample of 264 three- to five-year-old children and the parents or guardians of each child were individually interviewed to determine the body self-concepts of the children and factors associated with more positive body self-concepts. Of the factors examined—sex of child, nudity classification of family, race of child, area of the country, body build of child, years of education of head of household, birth order of child, age of child, age of parents or guardians, sex of interviewer, type of family structure, number of people in household, and number of siblings—only the first two were generally significant, with males having more positive body self-concepts than females (p < .001) and social nudists more positive body self-concepts than nonnudists (p < .001).
Visual feedback on nonverbal communication: a design exploration with healthcare professionals

Effective nonverbal communication between patients and clinicians fosters both the delivery of empathic patient-centered care and positive patient outcomes. However, few efforts to develop tools for enhancing clinician communication have focused on nonverbal aspects of the clinical encounter. We describe a novel system that both uses social signal processing technology (SSP) to capture nonverbal cues in real time and displays ambient visual feedback on control and affiliation---two primary, yet distinct dimensions of interpersonal nonverbal communication. To explore clinicians' acceptance of and reaction to an ambient visual feedback from such a system, we conducted a Wizard-of-Oz lab study to simulate system use with 16 healthcare professionals. We further followed up with 7 of those participants and iterated on the design with a new visualization. Our results indicate that reflective visual feedback on nonverbal communication provides an acceptable way to provide clinicians with awareness of their nonverbal communication. Furthermore, we discuss implications for the design of visual feedback to encourage empathic patient-centered communication.
A Case Report of Wernicke’s Encephalopathy in a Pediatric Patient with Anorexia Nervosa - Restricting Type

Abstract Purpose To describe a case of Wernicke's encephalopathy in a 15-year-old female patient with anorexia nervosa - restricting type. Method The patient and family were interviewed. Literature relevant to the case was reviewed prior to diagnosis. Results The patient reported a 30-kg weight loss over a 6-month period, following a strict diet deplete in thiamine without vitamin supplementation. The patient reported a carbohydrate binge for 5 days prior to admission. Her clinical presentation, confusion, ataxia, nystagmus, and magnetic resonance imaging demonstrating bilateral subthalamic hyperdensities were consistent with Wernicke's encephalopathy. Nutritional stabilization and parenteral thiamine replacement resulted in rapid improvement of her ataxia and nystagmus and contributed to her recovery. Conclusions Wernicke's encephalopathy should be considered in patients with anorexia nervosa. Thiamine therapy could be considered in cases of anorexia nervosa with significant confusion.
Engagement in Adulthood: Perceptions and Participation in Daily Activities

The present research explores how older adults experience daily activities through an application of the Day Reconstruction Method (Kahneman, Kreuger, Schakade, Schwartz, & Stone, 2004). Over the course of the day, individuals (N = 192, M = 72 years) spent an average of 14.50 hours engaged in a variety of activities. Individual differences in activity patterns could be partly explained by age and educational attainment. The oldest individuals (81-92 years) perceived lower levels of competence when engaging in daily activities. Regardless of age, however, individuals with greater educational attainment allocated more time and felt more intellectually challenged in their daily experiences.
A model for directed foreign gene delivery to rat liver cells in vivo.

Abstract A novel technique for directed delivery of retroviral genes to rat liver cells in vivo is described. Vascular isolation of the liver was achieved in situ and perfusate containing retrovirus expressing the bacterial gene conferring resistance to Hygromycin-B was delivered selectively to the posterior liver lobes. After 15 min, normal blood flow to the liver was restored. The portal venous branch supplying the two anterior liver lobes was ligated either at the same time (Group I, n = 4) or 20 hr prior to perfusion (Group II, n = 4) to stimulate DNA synthesis in the posterior lobes. Controls (Group III, n = 4) were perfused with retrovirus without portal branch ligation. Hepatocyte transduction was assessed 7 days later by isolating the cells and assessing their viability in a selection medium. In Group I and II rats, 9.2 ± 0.5 and 16.0 ± 1.0%, respectively, of harvested hepatocytes, expressed the Hygromycin-B gene. In contrast, a significantly smaller number of hepatocytes (2.8 ± 0.9%, P
Use of Data Envelopment Analysis in an Evaluation of the Efficiency of the DEEP Program for Economic Education.

The method of data envelopment analysis is used to show that participation in DEEP seems to increase the efficiency of some classes and decrease the efficiency of the other classes.
Mass sediment failure and transport features revealed by acoustic techniques, Beringian Margin, Bering Sea, Alaska

Abstract GLORIA sidescan sonar imagery and seismic‐reflection profiles show pervasive evidence for a wide variety of slides and slumps associated with the large canyons of the 1400‐km‐long Beringian margin. Styles of failure include mud and debris flows, slumps, and massive block slides. A 100‐km‐long shelf‐edge segment on the northern margin is characterized by a series of scalloped slide scars and incipient scars associated with sedimentary blocks, 1–2 km across, that seem to be the initiators of a series of small canyons. Some of the largest single slide masses, including huge blocks tens of kilometers wide, occur on the rise of the central margin. Sliding of these blocks may have initiated the incision of some of the world's largest submarine canyons, a prime example of which is the massive Zhemchug Canyon. Mass movement along the southern margin is widespread at the edges of Umnak Plateau. One mass failure, particularly well defined by GLORIA, is 55 km long. This slide and others along the plateau ar...
Roles and missions

Abstract Since the fall of the Berlin Wall, American military forces have been used to remove the ruler of Panama, to drive the Iraqi army out of Kuwait and later to deter its return, to alleviate a famine in Somalia, to remove a military junta from Haiti and restore the elected president to power, to compel warring ethnic factions in Bosnia to stop fighting and then to enforce the resulting truce until elections could be held, and to deter a threat from China against Taiwan, among other interventions. At the same time, American forces have been stationed in Korea to deter an attack from the north and in the Persian Gulf to deter aggressive actions by either Iran or Iraq.
Neural induction takes a transcriptional twist.

Over the past decade, several molecules have been identified that influence neural cell fate in vertebrate embryos during gastrulation. The first neural inducers studied were proteins produced by dorsal mesoderm (the Spemann organizer); most of these proteins act by directly binding to and antagonizing the function of bone morphogenetic proteins (BMPs). Recent experiments have suggested that other secreted signals, such as Wnt and FGF, may neuralize ectoderm before organizer function by a different mechanism. Neural effector genes that mediate the response of ectoderm to secreted neuralizing signals have also been discovered. Interestingly, most of these newly identified neuralizing pathways continue the theme of BMP antagonism, but rather than antagonizing BMP protein function, they may neuralize tissue by suppressing Bmp expression. Down-regulation of Bmp expression in the prospective neural plate during gastrulation seems to be a shared feature of neural induction in vertebrate embryos. However, the signals used to accomplish this task seem to vary among vertebrates. Here, we will discuss the role of the recently identified secreted signals and neural effector genes in vertebrate neurogenesis. © 2001 Wiley-Liss, Inc.
Dynamics of adsorption of colloidal particles in packed beds

Abstract This paper presents a combined theoretical and experimental study of deposition of colloidal particles in packed beds. It is shown experimentally that the rate of deposition declines rapidly with surface coverage even when the surface forces are favorable for deposition and that this decline is largely due to an excluded-area effect introduced by the surface-borne particles. The experimental data reveal that the above decline in the local rate can be expressed adequately in terms of a “desorption” term (that is linearly proportional to the surface concentration) in the rate equation; the coefficient of proportionality can be estimated a priori through a charge balance on the grains. In addition, the (local) rate of transport of the particles toward a typical grain in the bed is represented in the rate equation in terms of a cell model for the porous media. The above rate equation, in combination with an overall elemental mass balance in the bed, leads to a linear-chromatography-approximation for the dynamics of deposition in packed beds. This formalism permits one to take advantage of the extensive amount of work on packed bed adsorption already available in the literature and also leads to a closed form solution to the deposition problem. Although the experimental data reported here are obtained for deposition from aqueous suspensions, our experimental and theoretical results are shown to be in general agreement with a recent experimental study on nonaqueous suspensions as well.
Intraoperative conversion from endoscopic to microscopic approach for the management of sellar pathology: incidence and rationale in a contemporary series.

Background The endoscopic transsphenoidal approach has become widely used for pituitary and extended skull base operations. Intraoperative conversion to a microscopic approach may be an important option in selected cases. We aim to characterize the operative situations in which such conversion occurred and facilitated the procedure. Methods From April 2008 through August 2009, 148 planned endoscopic transsphenoidal approaches were performed. All cases were retrospectively reviewed to identify those patients converted to a microscopic approach. Clinical and operative characteristics, reasons for conversion, and patient outcomes were reviewed. Results Of the 148 endoscopic cases, conversion was undertaken in 27 (18%). Ten patients (37%) had undergone previous transsphenoidal surgery. Reasons for conversion in nonreoperation cases were atypical nasal anatomy (6 patients), acromegaly with distorted anatomy (5 patients), desire for binocular vision (3 patients), complex sphenoid sinus anatomy and difficulty visualizing sella/midline (2 patients), and obstructive mucosal bleeding (1 patient). Of the 10 reoperation procedures, conversions occurred in 3 patients with Cushing's disease and 2 with acromegaly. The primary reasons for conversion in reoperations were scarring with loss of anatomic landmarks (4 patients), mucosal bleeding (2 patients), acromegaly with distorted anatomy (2 patients), technical problem with visualization (1 patient), and desire for binocular surgery (1 patient). Conclusions Although endoscopic transsphenoidal surgery provides superior visualization in most patients, conversion to a microscopic or endoscopic-assisted approach may provide essential visualization in selected patients. This may be especially true in patients undergoing reoperation and patients with acromegaly or Cushing's disease. Trainees learning the endoscopic transsphenoidal approach should become familiar with the benefits and limitations of the various transsphenoidal approaches.
Efficient detection of a class of stable properties

We present a general protocol for detecting whether a property holds in a distributed system, where the property is a member of a class of stable properties we call the locally stable properties. Our protocol is based on a decentralized method for constructing a maximal subset of the local states that are mutually consistent, which in turn is based on a weakened version of vector time stamps. The structure of our protocol lends itself to refinement, and we demonstrate its utility by deriving some specialized property-detection protocols, including two previously-known protocols that are known to be efficient.
Decentralized control over analog erasure links

We consider decentralized control of a process with multiple sensors, controllers and actuators interconnected by analog erasure links. To stabilize the process, feedback information needs to be transmitted over both implicit signaling channels and external erasure channels. Based on a data flow network model, a necessary and sufficient condition for mean squared stabilizability of the process is obtained. Stabilizing algorithms are designed as a constructive proof for the sufficiency of the condition.
Properties of ribulose-1,5-bisphosphate carboxylase from dark- and light-exposed soybean leaves

Abstract The low activity of ribulose bisphosphate carboxylase from darkened soybean ( Glycine max [L.] Merr. cv. Bragg) leaves was not raised to the level of that from leaves in the light by CO 2 and Mg 2+ , even after a 4-h incubation. The extract of darkened leaves, unlike the extract from illuminated leaves, was not fully CO 2 /Mg 2+ -activatable after Sephadex gel filtration in the absence of Mg 2+ . (NH 4 ) 2 SO 4 fractionation eliminated the inhibition effect found in the dark extracts resulting in similar rates for the extracts obtained from leaves in the dark and light. Although the V max values of the gel-filtered extracts from dark and light leaves differed by 3-fold, the K m (CO 2 )-values were the same (12.7 μM), as were the K m (RuBP)-values (250 μM). These data support the hypothesis that for soybean leaves in the dark a tightly-binding inhibitor renders much of the ribulose bisphosphate carboxylase enzyme catalytically non-functional.
Complexities of efficient solutions of rectilinear polygon cover problems

The rectilinear polygon cover problem is one in which a certain class of features of a rectilinear polygon ofn vertices has to be covered with the minimum number of rectangles included in the polygon. In particular, we consider covering the entire interior, the boundary, and the set of corners of the polygon. These problems have important applications in storing images and in the manufacture of integrated circuits. Unfortunately, most of these problems are known to be NP-complete. Hence it is necessary to develop efficient heuristics for these problems or to show that the design of efficient heuristics is impossible. In this paper we show: (a) The corner cover problem is NP-complete. (b) The boundary and the corner cover problem can be approximated within a ratio of 4 of the optimum inO(n logn) andO(n 1.5) time, respectively. (c) No polynomial-time approximation scheme exists for the interior and the boundary cover problems, unless P=NP.
Spending Patterns with Lapsing Budgets: Evidence from U.S. Army Hospitals

We explore how the practice of reverting unused funds (budget lapsing) affects intra‐ and inter‐year spending patterns. Data from 31 army hospitals over a period of five years provide strong support for a saving‐dissaving model. Hospital administrators appear to stockpile pharmaceuticals and other supplies toward the end of a fiscal year, leading to a significant spike in spending that potentially exhausts their budget. Interestingly, data show a decline at the start of the next fiscal year that is larger than the preceding spike, indicating that mangers build a reserve for later use. The magnitude of the reserve accumulated at the start of a year is reliably persistent across years and accelerates the upward trend in spending through the year. That is, managers increasingly expend the reserve as environmental uncertainty decreases.We conclude that risk‐aversion plays a significant role in determining intra‐year trends.
Modulation of hepatic glucose-6-phosphate dehydrogenase activity in male and female rats by estrogen

Abstract The effect of estradiol-17β on the activity of glucose-6-phosphate dehydrogenase was studied in both male and female rats to further characterize the sex differences in the activity of this enzyme. Four groups of intact and castrated rats were implanted subcutaneously with graded doses (2.4, 4.8 and 7.2 μg/day) of pelleted estradiol in a physiologically relevant experimental system. After fourteen days the rats were sacrificed and their livers were assayed for G6PD activities. The result indicated that: (i) the enzyme activity was 3-fold higher in normal adult female than in male rats, (ii) low doses of E 2 (2.4, 4.8 and 7.2 μg/day) increased the activity of G6PD 6-fold in castrated males and over 2-fold in female castrates as well as intact rats (iii) E 2 stimulation of G6PD activity appears to be more effective in castrated males than in female rats (iv) sex difference in the activity of G6PD disappeared after treatment with E 2 in castrated rats. It is concluded that the activity of G6PD in rats is markedly enhanced by low doses of E 2 , which appears to be largely responsible for the sex differences in the activity of this enzyme in rats.
A tale of three buildings: Certifying virtue in the new moral economy

One expression of the spread of auditing and bureaucratic accountability in global society is the emergence of certifications of virtue, typically after completion of a review process designed to ensure objectivity. In this article, I analyze regulatory interactions in a U.S. construction project, including the procedure for formally certifying buildings as energy efficient and “sustainable,” to bring into focus the sometimes-paradoxical effects that highly rationalized regulations have on those obliged to comply with them. The case illustrates how virtue is reduced to a checklist of measurable properties whose integrity is maintained through rituals of verification and rigorous risk management. The issues involved lead me to reflect on anthropologists’ inclination to demonize bureaucratic regulation in their ethnographic accounts even as they insist on formal accountability in their own communities and professional networks.
A difference in the sequence of steps in the reactions catalyzed by two closely homologous forms of glutamate dehydrogenase

Glutamate dehydrogenase from beef liver (bl GDH) and the corresponding enzyme from Clostridium symbiosum (cs GDH) each catalyze the same sequence of chemical events in the oxidative deamination of l-glutamate. This catalysis involves interactions between at least six conserved functional groups, each of which appears to occupy the same geometric position with respect to the substrate molecule in both enzyme−coenzyme−l-glutamate reactive ternary complexes. In both cases steady-state V/K pH profiles indicate the requirement for the transfer to the solvent of a single proton from the same abnormal lysine for l-glutamate to bind and react; the pK of that lysine is the same for both enzymes. Here we report studies of the proton traffic between enzyme and solvent using direct pH-stat back-titration and indicator dye measurements on dead-end inhibitor ternary complexes, simultaneous transient-state time courses of proton and product, and transient-state kinetic isotope studies on both enzymes. We find that in th...
Patterns of hippocampal theta rhythm in the freely moving rat.

Abstract Theta activity was investigated during the two behavioral states in which this activity occurs in the freely moving rat, namely, movement (such as exploration) and paradoxical sleep. The patterns of theta activity are basically the same in both conditions. Dorsoventral microelectrode penetration of the dorsal hippocampus shows a maximal amplitude of activity in the CA 1 pyramidal layer. With further penetration, the theta activity gradually reverses phase, the reversal being complete at the hippocampal fissure. A second maximal amplitude occurs in the dorsal blade of the dentate gyrus, there being no further change of phase. The theta activity that occurs in the presence of eserine and curare was found to have a different amplitude and phase profile from that in the freely moving rat.
Studies of amine‐induced ring opening of some mesoionic xanthines

The ring-opening reactions of seven mesoionic thiazolo[3,2-a]pyrimidine-5,7-diones by a series of primary and secondary amines have been investigated. The rates of the ring fission of five N(8)-substituted mesoionic xanthines with benzylamine were measured and found to follow second order kinetics. The Hammett relationship is followed with ϱ value of + 0.48 in p-dioxane as solvent. The dependence of rates on temperatures has been studied for the N(8)-ethyl derivative; the energy of activation (ΔE*) is 25.3 kcals mol−1, the enthalpy of activation (ΔH*) is 24.7 kcals mol−1 and the entropy of activation (ΔS*) is — 4.9 e.u. A slight increase in rate of reaction was observed when the solvent was changed from p-dioxane to dimethyl sulfoxide. In p-dioxane at constant mesoionic xanthine concentration, the rate constant for ring opening decreased with increasing benzylamine concentration. These results are consistent with a bimolecular nucleophilic mechanism proceeding by the rate-determining formation of a charged tetrahedral transition state.
Elimination of artifactual accumulation of FDG in PET imaging of colorectal cancer.

Background: Positron emission tomography (PET) with fluorine-18 labeled deoxyglucose (FDG) can detect tumor recurrences in surgical patients that are otherwise difficult to assess by CT, as well as distant metastases and small malignant nodes that are not identified by other imaging modalities. However, the evaluation of such malignancy is complicated by urinary and colonic concentrations of FDG. Methods and examples of the elimination of artifactual accumulation of FDG in PET imaging of the abdomen and pelvis are presented. Methods: Elimination of artifactual accumulation requires patient preparation that begins with cleansing of the colon using an isosmotic solution taken the evening prior to examination. Approximately 500 MBq of F-18 FDG is intravenously administered upon arrival at the PET facility and then the patient is hydrated. After administration of furosemide, a Foley catheter with a drainage bag is placed and the patient is then scanned. Just prior to scanning over the pelvis, normal saline is delivered retrogradely into the urinary bladder. At the end of scanning, the patient voids and repeated pelvic images are obtained. Results: These routines yield a clean scanning field. Lesions that will generally be missed because they are obscured by FDG accumulations along the colon or in the kidneys, ureters, or bladder are better visualized and identified with greater confidence. Artifacts that lead to misinterpretation also are reduced. Conclusion: Elimination of artifactual accumulation of FDG in the colon and urinary system is essential if primary cancer, associated adenopathy, or subtle recurrences are to be evaluated in FDG PET imaging of the abdomen and pelvis.
Selective Internal Oxidation as a Mechanism for Intergranular Stress Corrosion Cracking of Ni-Cr-Fe Alloys

The mechanism of selective internal oxidation (SIO) for intergranular stress corrosion cracking (IGSCC) of nickel-base alloys has been investigated through a series of experiments using high-purity alloys and a steam environment to control the formation of NiO on the surface. Five alloys (Ni-9Fe, Ni-5Cr, Ni-5Cr-9Fe, Ni-16Cr-9Fe, and Ni-30Cr-9Fe) were used to investigate oxidation and intergranular cracking behavior for hydrogen-to-water vapor partial pressure ratios (PPRs) between 0.001 and 0.9. The Ni-9Fe, Ni-5Cr, and Ni-5Cr-9Fe alloys formed a uniform Ni(OH)2 film at PPRs less than 0.09, and the higher chromium alloys formed chromium-rich oxide films over the entire PPR range studied. Corrosion coupon results show that grain boundary oxides extended for significant depths (>150 nm) below the sample surface for all but the highest Cr containing alloy. Constant extension rate tensile (CERT) test results showed that intergranular cracking varied with PPR and cracking was more pronounced at a PPR value where nonprotective Ni(OH)2 was able to form and a link between the nonprotective Ni(OH)2 film and the formation of grain boundary oxides is suggested. The observation of grain boundary oxides in stressed and unstressed samples as well as the influence of alloy content on IG cracking and oxidation support SIO as a mechanism for IGSCC.
Computer Programs for Performing Iterative Partitioning Cluster Analysis

Eight programs which perform iterative partition ing cluster analysis are analyzed; they are discussed in terms of versatility of options, accuracy, and cost. These eight programs contain very different heuristic approaches to finding the optimal partition of a data set; the different heuristic approaches are shown to affect both accuracy and cost of clustering solutions. It was not possible to recommend any one program as generally being preferable, however, because of the striking variability in these programs and the lack of knowledge about iterative partitioning methods.
Seismic Analysis of the National Compact Stellarator Experiment (NCSX)

DOE requirements as outlined in DOE-STD-1020-2002 are followed for determination of the necessity for seismic qualification of the stellarator and its related systems. IBC-2000 is followed for the qualification requirements The NCSX criteria document[2] provides guidance on load combinations. The stellarator presents minimal occupational hazards and hazards to the public. The qualification effort is intended to preserve the viability of continuing the experiment after an earthquake, and to explore the sensitivity of the design to dynamic loading from sources other than normal operation. A response spectra modal analysis has been employed. The seismic model builds on available conceptual design and design models of the vessel, and modular coil. Outer TF and PF coil models and models of the cold mass supports have been generated and added to form a complete model of the stellarator system. Much of the stellarator is robust to resist normal Lorentz forces. Areas sensitive to lateral loads and dynamic application of non-Lorentz loading, include the nested cylinder cold mass support columns, cantilevered vessel ducts, and the radial guides connecting the vessel ducts and modular coil shell. Loads on these structures are quantified, and design adequacy is assessed.
Student Models of Instructional Design.

Mental models are one way that humans represent knowledge (Markman, 1999). Instructional design (ID) is a conceptual model for developing instruction and typically includes analysis, design, development, implementation, and evaluation (i.e., ADDIE model). ID, however, has been viewed differently by practicing teachers and instructional designers (Kennedy, 1994). In a graduate ID course students constructed their own ID models. This study analyzed student models for (a) what ADDIE components were included (by teacher, nonteacher), and (b) model structural characteristics (by teacher, nonteacher). Participants included 178 students in 12 deliveries of a master's level ID course (115 teachers, 63 nonteachers). Our conceptual ID model is presented, and the ID model task is described. Students most frequently represented design, followed by program evaluation, needs assessment, development, and implementation. In terms of structural characteristics, 76 models were characterized as metaphoric, 61 dynamic, and 35 sequential. Three interrelated conclusions and implications for ID learning are offered.
Energy Efficient Coverage with Variable Sensing Radii in Wireless Sensor Networks

Wireless sensor networks (WSN) consist of spatially distributed autonomous devices using sensors to cooperatively monitor physical or environmental conditions. Generally, sensor nodes are resource-constraint in terms of size, power and bandwidth, therefore energy-efficient design becomes one of the fundamental goals in WSN. To provide reliable service in surveillance as well as energy efficiency, significant attention has recently been devoted to dynamic coverage algorithms based on sensors which are capable of adjusting its transmission and sensing range. In this paper, we propose two local sensing radii optimization schemes based on one-hop approximation of Delaunay Triangulation to minimize the energy consumption and extend the lifetime of networks. Furthermore, we prove that our approximation of Delaunay triangulation guarantees complete coverage and generates the same radii assignment as traditional Delaunay triangulation. Our ns-2 based simulation shows performance improvements in many aspects such as coverage ratio, sensing energy consumption, node failure rate, and lifetime of networks.
Cyberinfrastructure Usage Modalities on the TeraGrid

This paper is intended to explain how the Tera Grid would like to be able to measure "usage modalities." We would like to (and are beginning to) measure these modalities to understand what objectives our users are pursuing, how they go about achieving them, and why, so that we can make changes in the Tera Grid to better support them.
MCF-10A-NeoST: A New Cell System for Studying Cell-ECM and Cell-Cell Interactions in Breast Cancer

Purpose: There is a continuing need for genetically matched cell systems to model cellular behaviors that are frequently observed in aggressive breast cancers. Experimental Design: We report here the isolation and initial characterization of a spontaneously arising variant of MCF-10A cells, NeoST, which provides a new model to study cell adhesion and signal transduction in breast cancer. Results: NeoST cells recapitulate important biological and biochemical features of metastatic breast cancer, including anchorage-independent growth, invasiveness in three-dimensional reconstituted membranes, loss of E-cadherin expression, and increased tyrosine kinase activity. A comprehensive analysis of tyrosine kinase expression revealed overexpression or functional activation of the Axl, FAK, and EphA2 tyrosine kinases in transformed MCF-10A cells. Conclusions: MCF-10A and these new derivatives provide a genetically matched model to study defects in cell adhesion and signaling that are relevant to cellular behaviors that often typify aggressive breast cancer cells.
Modeling and control of distributed generation systems including PEM fuel cell and gas turbine

This paper concentrates on the modeling and control of distributed generation systems including fuel cell and gas turbine. The fuel cell is connected to the power system through a dc/ac converter, which is equipped with both voltage- and power-control loops. The gas turbine is also assumed to be equipped with both voltage-control and generation (or frequency)-control loops. Moreover the gas turbine is modeled using the d–q frame of reference. The interfacing of the gas turbine with the power system is achieved by transforming its equations from the d–q frame of reference to power system frame of reference. A multivariable supplementary fuzzy logic controller is proposed for improving the dynamics of the combined fuel cell and gas turbine system. This fuzzy logic controller is designed using the Matlab Fuzzy Logic Toolbox A distribution test system including a load, a fuel cell and a gas turbine, connected to a power grid is simulated using Matlab/Simulink software package. The dynamics of the combined distributed generation plant are analyzed for the cases of with and without controller. The accuracy of the presented model and the effectiveness of the proposed multivariable supplementary fuzzy controller are deduced from the simulation results.
AVM: application-level virtual memory

Virtual memory (VM) is a notoriously complicated abstraction to implement, and is hard to change, specialize, or replace. Although a certain degree of flexibility is achieved by user-level pagers, the control they provide is limited: they leave much of the VM system fixed in the kernel, unreachable by the application. As applications become more diverse and the opportunity cost of bad memory policies grows, it is essential for applications to have more control over the VM abstraction. We motivate and describe a VM system that is implemented completely at the application level. To the best of our knowledge this system is the first complete example of application-level virtual memory (AVM). AVM allows applications to easily specialize, modify, or even replace the VM abstractions offered. For example, on architectures with software TLB management, applications can even select their own page-table structures. In addition, AVM simplifies the OS kernel, since the kernel only multiplexes and does not abstract physical memory. A prototype AVM system is implemented for Aegis, an experimental exokernel.
Neutrinos and the dark matter of the universe

Abstract Neutrinos were the first non-baryonic candidate to be considered as the source of most of the mass of the universe. There is increasing evidence that about 99% of that mass has not yet been observed by other than its gravitational effects. Perhaps ∼ 5% of this is in the form of ordinary matter, very likely mainly small, non-luminous stars, such as have started to be observed by gravitational microlensing. All the rest must be due to particles not in the Standard Model of particle physics, most likely ∼ 70% being cold dark matter and the remainder hot dark matter. Light neutrinos, the best candidate for the latter, have to be searched for in terrestrial experiments, such as looking for neutrino oscillations or neutrinoless double beta decay, and there is now interesting guidance for this search. Heavy fourth-generation neutrinos have been eliminated as cold dark matter by accelerator experiments and underground direct detection experiments. A wide range of possible masses (12 orders of magnitude) and interaction cross sections (20 orders of magnitude) for Dirac cold dark matter candidates have been eliminated by direct detection. New direct detection experiments will utilize large scintillators or interesting cryogenic detectors to look for Dirac candidates with mass > 20 GeV and cross sections less than one-tenth that of the weak interaction. Using detector nuclei with spin, they will also search for Majorana particles, especially with mass ≳ 10 GeV, as will very large underground detectors which look for neutrinos from the annihilation of pairs of dark matter particles.
Government Contracts and “Managing the Market” Exploring the Costs of Strategic Management Responses to Weak Vendor Competition

Theory tells us that competition is the chief driver of improved efficiency and effectiveness in government contracting, yet contract provider markets are often noncompetitive. This study offers a detailed, contextualized examination of public administrative responses to thin contract markets. Following an inductive approach with data from semistructured interviews with contract administrators, the authors offer a preliminary typology of the conditions that give rise to thin markets, and the “market management” strategies used to create, enhance, and sustain competition in the markets from where governments purchase goods and services. The authors then review the efficacy and implications of these strategies for public services to citizens.
Understanding the efficiency of autonomous nano- and microscale motors.

We analyze the power conversion efficiency of different classes of autonomous nano- and micromotors. For bimetallic catalytic motors that operate by a self-electrophoretic mechanism, there are four stages of energy loss, and together they result in a power conversion efficiency on the order of 10–9. The results of finite element modeling agree well with experimental measurements of the efficiency of catalytic Pt–Au nanorod motors. Modifications of the composition and shape of bimetallic catalytic motors were predicted computationally and found experimentally to lead to higher efficiency. The efficiencies of bubble-propelled catalytic micromotors, magnetically driven flagellar motors, Janus micromotors driven by self-generated thermal gradients, and ultrasonically driven metallic micromotors are also analyzed and discussed.
Amaranthus hybridus populations resistant to triazine and acetolactate synthase‐inhibiting herbicides

Summary Amaranthus hybridus L. populations (A, B and C) obtained from escapes in Massac County and Pope County fields in southern Illinois, USA were subjected to greenhouse and laboratory experiments to measure multiple resistance to triazine and acetolactate synthase (ALS)-inhibiting herbicides and cross-resistance between sulfonylurea and imidazolinone herbicides. Phytotoxicity responses of the three populations revealed that only population B exhibited multiple resistances to triazine and ALS-inhibiting herbicides. This population was >167-, >152- and >189-fold resistant to atrazine, imazamox and thifensulfuron, respectively, at the whole plant level compared with the susceptible population. Population A was only resistant to triazines and population C was only resistant to ALS-inhibiting herbicides. Results from in vivo ALS enzyme and chlorophyll fluorescence assays confirmed these findings and indicated that an altered site-of-action mediated resistance to both triazine and ALS-inhibiting herbicides. Gene sequencing revealed that a glycine for serine substitution at residue 264 of the D1 protein, and a leucine for tryptophan substitution at residue 574 of ALS were the causes of resistance for the three populations.
Neural correlates of infants' visual responsiveness to facial expressions of emotion

An extensive literature documents the infant's ability to recognize and discriminate a variety of facial expressions of emotion. However, little is known about the neural bases of this ability. To examine the neural processes that may underlie infants' responses to facial expressions, we recorded event-related potentials (ERPs) while 7-month-olds watched pictures of a happy face and a fearful face (Experiment 1) or an angry face and a fearful face (Experiment 2). In both experiments an early positive component, a middle-latency negative component and a later positive component were elicited. However, only when the infants saw the happy and fearful faces did the components differ for the two expressions. These results are discussed in the context of the neurobiological processes involved in preceiving facial expressions.
Federal Regulation of Electronic Flight Bags

This paper consists of student legal scholarship regarding one aspect of the present regulatory environment for commercial aviation. The press has reported that US commercial airlines are equipping their pilots with tablet computer “Electronic Flight Bags” to replace the paper documents pilots presently carry. This scholarship has found that the FAA permits the use of tablet computers on the flight deck through a “non-legislative-rule.” This agency issued rule was made outside of “Notice-and-Comment” lawmaking. The rule is not legally binding in the way that officially promulgated Federal Regulations are. Because legal precedent does not provide a safe harbor to operators who rely upon the statements of government officials made in the absence of formal Federal Regulation, it would be advantageous for the industry to petition the FAA to formally codify rules to govern how pilots may rely upon Electronic Flight Bags.
Gravity inversion using seismically derived crustal density models and genetic algorithms: An application to the Caribbean-South American Plate boundary

SUMMARY Crustal density models derived from seismic velocity models by means of velocity–density conversions typically reproduce the main features of the observed gravity anomaly over the area but often show significant misfits. Given the uncertainty in the relationship between velocity and density, seismically derived density models should be regarded as an initial estimate of the true subsurface density structure. In this paper, we present a method for estimating the adjustments necessary to a seismically derived density model to improve the fit to gravity data. The method combines the Genetic Algorithm paradigm with linear inversion as a way to approach the non-linear and linear aspects of the problem. The models are divided into three layers representing the sedimentary column, the crystalline crust and the lithospheric mantle; the depths of these layers are determined from the seismic velocity model. Each of the layers is divided into a number of provinces and a density adjustment (Δρ) value is found for each province so that the residual gravity (difference between the observed gravity anomaly and the anomaly calculated for the seismically derived model) is minimized while keeping Δρ between predefined bounds. The preferred position of the province boundaries is found through the artificial evolution of a population of solutions. Given the stochastic nature of the algorithm and the non-uniqueness of the problem, different realizations can yield different solutions. By performing multiple realizations we can analyse a set of solutions by taking their mean and standard deviation, providing not only an estimate of the Δρ distribution in the subsurface but also an estimate of the associated uncertainty. Synthetic tests prove the ability of the algorithm to accurately recover the location of province boundaries and the Δρ values for a known model when using noise-free synthetic data. When noise is added to the data, the algorithm broadly recovers the features that define the known model despite greater standard deviations of the solutions and the occurrence of artefacts in the mean solutions. The algorithm was applied to four profiles across the Caribbean–South America Plate boundary. Some general patterns in the distribution of Δρ were observed consistently in the profiles and are correlated with the interpretations of the velocity models. Positive Δρ values in the sedimentary layer, negative Δρ values for island arc and extended island arc crust with an abrupt change to positive values in South American crust, and positive values in the mantle under the continent and island arc with a transition to negative values under the Caribbean oceanic crust.
Statistics pattern analysis: A new process monitoring framework and its application to semiconductor batch processes

In the semiconductor industry, process monitoring has been recognized as a critical component of the manufacturing system. Multivariate statistical process monitoring (SPM) techniques, such as multiway principal component analysis and multiway partial least squares, have been extend to monitor semiconductor processes. These SPM methods require extensive, often off-line data preprocessing such as data unfolding, trajectory mean shift, and trajectory alignment. This requirement is probably not an issue for the traditional chemical batch processes but it poses a significant challenge for semiconductor batch processes. This is because data preprocessing makes model building and maintenance extremely labor intensive due to the large number of models in a typical semiconductor fab. In addition, semiconductor process data often show more severe nonnormality compared to those of the traditional chemical process under closed-loop control, which results in suboptimal performance in many applications. To address these challenges, several pattern classification based monitoring (PCM) methods have been developed recently, but some limitations remain and trajectory alignment is still required. In this article, we analyze the fundamental reasons for the limitations of the SPM and PCM methods when applied to monitor semiconductor processes. In addition, we propose a new statistics pattern analysis (SPA) framework to address the challenges associated with semiconductor processes. By monitoring batch statistics, the proposed SPA framework not only eliminates all data preprocessing steps but also provides superior fault detection performance. Finally, we use an industrial example to demonstrate the advantages of the proposed SPA framework, and examine the fundamental reasons for the improved performance from SPA. © 2010 American Institute of Chemical Engineers AIChE J, 2011