cssi/SciSciGPT-SciSciNet huggingface dataset:
Ultrasound-induced calcium oscillations and waves in Chinese hamster ovary cells in the presence of microbubbles.

This study investigated the effects of ultrasound on the intracellular [Ca2+] of Chinese hamster ovary cells in the presence of albumin-encapsulated Optison microbubbles. Cells were exposed to 1 MHz ultrasound (tone burst of 0.2 s duration, 0.45 MPa peak pressure) while immersed in solution of 0.9 mM Ca2+. Calcium imaging of the cells was performed using digital video fluorescence microscopy and Ca2+-indicator dye fura-2AM. Experimental evidence indicated that ultrasound caused a direct microbubble-cell interaction resulting in the breaking and eventual dissolution of the microbubble and concomitant permeabilization of the cells to Ca2+. These cells exhibited a large influx of Ca2+ over 3–4 s and did not return to their equilibrium levels. Subsequently, some cells exhibited one or more Ca2+ oscillations with the onset of oscillations delayed by 10–80 s after the ultrasound pulse. A variety of oscillations were observed including decaying oscillations returning to the baseline value over 35–100 s, oscillations superimposed on a more gradual recovery over 150–200 s, and oscillations continued with increased amplitude caused by a second ultrasound tone burst. The delays in onset appeared to result from calcium waves that propagated across the cells after the application of the ultrasound pulse.
Magnetic penetration depths in superconducting Nb films

Absolute magnetic penetration depths λ in evaporated Nb films have been measured as a function of residual resistivity ϱTc and temperature T by means of a refined two-junction junction interferometer technique. The measured λ(ϱTc) dependence is within the local London theory with ξ0=410A and λL(0) = 440 A, and the experimental λ(T) follows the empirical approximation λ(T) = λ(0)(1−T4T4c)12, where Tc = 9.0 K for a film with ρTc = 5.8 μΩcm. To our knowledge, this is the first experimental test of λ(ρTc) in Nb.
Investigation of interfacial reactions in thin film couples of aluminum and copper by measurement of low temperature contact resistance

Abstract Interfacial reactions in bimetallic thin film couples of aluminum and copper were investigated by measurement of contact resistance between 4.2 and 300 K. Results for as-deposited couples indicate that electrical properties, such as resistance and temperature coefficient of resistance, correspond closely to those computed from a simple model involving current flow parallel to the interface. These properties change appreciably after step annealing at elevated temperatures. Results in this case indicate that interfacial reactions commence by nucleation and growth of Al2Cu along grain boundaries at 145°C, whereas significant solid solution alloying precedes nucleation and growth of intermetallic compounds at 250°C. Homogenization of these couples proceeds, sequentially, by (1) rapid diffusion of aluminum along grain boundaries in copper, (2) rapid diffusion of copper along grain boundaries in aluminum and (3) slower diffusion of each species into grain interiors of the other until a uniform composition, controlled by relative thickness of the constituent films, is achieved. This interpretation of the evolution of contact resistance is entirely consistent with complementary microstructural characterization by optical and transmission electron microscopy and chemical characterization by Auger electron spectroscopy.
College Women Who Initiate Assaults on Their Male Partners and the Reasons Offered for Such Behavior

Studies of spousal and dating violence indicate that women are as likely as men to assault their partners physically. This investigation examined the issue of the initiation of physical assaults by women on their male partners and the reasons offered for such behavior. Responses from 978 female college women indicate that, within a 5-yr. period, 29% (n = 285) admitted to physical aggression against their male partners. Younger women in their 20's were significantly more likely to aggress physically than women who were 30 yr. and above. Women stated that they expressed aggression toward their male partners in part because they wished to engage their partner's attention, particularly emotionally. Also, assaultive women did not believe that their male victims would be seriously injured or would retaliate.
The Evolution of the Martian Hydrosphere: Implications for the Fate of a Primordial Ocean and the Current State of the Northern Plains

In this paper we consider the hydraulic and thermal conditions that gave rise to the elevated source regions of the Late Hesperian outflow channels and explore their implications for the evolution of the Martian hydrosphere. We find that if the outflow channel floodwaters were derived from a subpermafrost aquifer, then it implies that, throughout the planet's first billion years of evolution, as much as one third of its surface was covered by standing bodies of water and ice. Following the development of the global dichotomy, the bulk of this water would have existed as an ice-covered ocean in the northern plains. We demonstrate that the progressive crustal assimilation of this early surface reservoir of H2O (punctuated by possible episodes of less extensive flooding) was a natural consequence of the planet's subsequent climatic and geothermal evolution-potentially cycling the equivalent of a km-deep global ocean of water through the atmosphere and subsurface every approx. 10(exp 9) years. In response to the long-term decline in planetary heat flow, the progressive coldtrapping of H2O into the growing cryosphere is expected to have significantly depleted the original inventory of groundwater-a development that could well explain the apparent decline in outflow channel activity observed during the Amazonian. Although primarily a theoretical analysis, our findings appear remarkably consistent with the geomorphic and topographic evidence that Mars once possessed a primordial ocean and that a substantial relic of that body continues to survive as massive ice deposits within the northern plains. Confirmation of the presence of such deposits, combined with the potential detection of a global-scale groundwater system, would provide persuasive support for the validity of this analysis.
Evaluation of methylene blue and riboflavin for the photosensitized degradation of ethylene glycol

Degradation rates ranging from 0.22 ± 0.11 to 1.52 ± 0.50 mg/L-h were measured for ethylene glycol in riboflavin solutions exposed to natural sunlight. Significant degradation rates were noted in systems using 6 and 10 mg/L riboflavin at pH values of 4, 7, and 10. No significant degradation was found in systems using methylene blue as the photosensitizing agent. Possible mechanisms for ethylene glycol degradation include a combination hydrogen or electron abstraction by an excited photosensitizer and reaction with singlet oxygen or reaction with superoxide radicals.
Spontaneous generation of voltage in the magnetocaloric compound Tb5Si2.2Ge1.8 and elemental Gd

Abstract The spontaneous generation of voltage (SGV) in single crystalline Tb 5 Si 2.2 Ge 1.8 and Gd has been studied. Temperature-induced SGVs were observed along the three principal crystallographic axes of Tb 5 Si 2.2 Ge 1.8 , but not in Gd. Field-induced SGVs were observed with magnetic fields less than 40 kOe applied along the a -axis of Tb 5 Si 2.2 Ge 1.8 , and the c -axis of Gd. The absence of the temperature-induced SGV in Gd indicates the key role first-order phase transformations play in the appearance of the effect when temperature varies. The anisotropy of the magnetic field-induced SGV in Tb 5 Si 2.2 Ge 1.8 and the existence of the field-induced SGV in Gd, highlight the importance of the magnetocaloric effect in bringing about the SGV.
Frequency of congestive heart failure in older persons with prior myocardial infarction and serum low-density lipoprotein cholesterol ≥125 mg/dl treated with statins versus no lipid-lowering drug

(TIMI II) Trial. The TIMI research group. Am J Cardiol 1993;71:1148–1152. 11. Zeymer U, Neuhaus KL, Wegscheider K, Tebbe U, Molhoek P, Schroder R. Effects of thrombolytic therapy in acute inferior myocardial infarction with or without right ventricular involvement. J Am Coll Cardiol 1998;32:876–881. 12. Braat SH, Brugada P, De Zwaan C, Coenegracht JM, Wellens HJ. Value of electrocardiogram in diagnosing right ventricular involvement in patients with acute inferior wall myocardial infarction. Br Heart J 1983;49:368–372. 13. Candell-Riera J, Figueras J, Valle V, Alvarez A, Gutierrez L, Cortadellas J, Cinca J, Salas A, Rius J. Right ventricular infarction relationship between ST segment elevation in V4R and hemodynamic, scintigraphic and echocardiographic findings in patients with acute inferior myocardial infarction. Am Heart J 1981;101:281–287. 14. Chesebro JH, Knatterud G, Roberts R, Borer J, Cohen LS, Dalen J, Dodge HT, Francis CK, Hillis D, Ludbrook P. Thrombolysis in Myocardial Infarction (TIMI) trial, phase I. A comparison between intravenous tissue plasminogen activator and intravenous streptokinase: clinical findings through hospital discharge. Circulation 1987;76:142–154. 15. Schiller NB, Shah PM, Crawford M, DeMaria A, Devereux R, Feigenbaum H, Gutgesell H, Reichek N, Sahn D, Schnittger I. Recommendations for quantitation of the left ventricle by two-dimensional echocardiography. J Am Soc Echocardiogr 1989;2:358–367. 16. Giannitsis E, Hartmann F, Wiegand U, Katus HA, Richardt G. Clinical and angiographic outcome of patients with acute inferior myocardial infarction. Z Kardiol 2000;89:28–35. 17. Ribichini F, Steffenino G, Dellavalle A, Ferrero V, Vado A, Feola M, Uslenghi E. Comparison of thrombolytic therapy and primary coronary angioplasty with liberal stenting for inferior myocardial infarction with precordial ST segment depression: immediate and long-term results of a randomized study. J Am Coll Cardiol 1998;32:1687–1694. 18. Shiraki H, Yoshikawa T, Anzai T, Negishi K, Takahashi T, Asakura Y, Akaishi M, Mitamura H, Ogawa S. Association between preinfarction angina and a lower risk of right ventricular infarction. N Engl J Med 1998;338:941–947. 19. Bates ER. Revisiting reperfusion therapy in inferior myocardial infarction. J Am Coll Cardiol 1997;30:334–342. 20. O’Rourke R. Treatment of right ventricular infarction: thrombolytic therapy, coronary angioplasty or neither? J Am Coll Cardiol 1998;32:882–884.
Changes in readiness to quit and self-efficacy among adolescents receiving a brief office intervention for smoking cessation

Abstract Purpose: To examine changes in readiness to quit and self-efficacy among adolescents who received a clinic-based, brief office intervention (BOI) for smoking cessation. Methods: This study utilized a prospective, pre–post- treatment design. Participants were adolescent smokers (34 females, 35 males) with a mean ± SD age of 15.8 ± 1.4 years; 86% were Caucasian, who were randomly assigned to receive the BOI as part of a larger clinical trial. They were recruited from three cities in the Midwest and Northeastern part of the United States. After the baseline assessment, the BOI was designed for adolescents to receive four weekly individual sessions with a research counselor lasting between 10 and 40 min each. The BOI includes motivational interviewing and cognitive–behavioral techniques. Readiness to quit was assessed at each treatment session using the stages of change algorithm. The validated Adolescent Smoking Self-Efficacy Scale (SES) was used to assess self-efficacy at baseline (week 0) prior to...
Amphiphilicity in Homopolymer Surfaces Reduces Nonspecific Protein Adsorption

Amphiphilic homopolymer films have been immobilized onto substrates to study the interactions of these polymers with proteins. X-ray photoelectron spectroscopy (XPS) was utilized to measure the amount of protein adsorption. Amphiphilic homopolymers have been shown to reduce protein adsorption, despite the high affinity of the hydrophobic or hydrophilic functional groups by themselves toward proteins. This protein-resistant property seems to arise from the unique molecular-scale alternation of incompatible functionalities. The combination of incompatible functionalities with a predefined alternating pattern within a monomer could provide a potential design for nonfouling materials.
How voters work around institutions: Policy balancing in staggered elections

Abstract This work provides a general framework for analysis of issue voting across democratic polities. Unlike current frameworks of analysis for issue voting, I argue that voters are concerned not only with party positions, but also with policy outcomes. This simple principle carries implications for voter choice under various institutional environments. In consensual parliamentary systems, taking into consideration the bargaining built into policy formation process in the parliament, voters often endorse parties whose positions differ from their own views. In presidential elections, incorporating the compromise between the president and the legislature into their decision making, voters adjust their vote, balancing the two institutions against one another. Finally, in federal systems, voters engage in vertical balancing, utilizing state elections to balance the federal government. I illustrate the latter implication analyzing election returns from Germany between 1965 and 2002.
The Maturing Brain Methylome

The methylation of DNA in mammalian genomes regulates gene expression, guiding differentiation and maintaining cellular identity within tissues. However, it may have a distinct function in the brain. On page 629 of this issue, Lister et al. ( 1 ) present a comprehensive analysis of DNA methylation and hydroxymethylation at single-base resolution in the mammalian frontal cortex. The authors chart out striking postnatal alterations in neuronal methylation profiles that occur as synapses develop and are refined, from the fetal to adult stage. The patterns suggest that DNA methylation is important in the maturation of neurons in the developing brain.
A scalable eigenvalue solver for symmetric tridiagonal matrices

Abstract Both massively parallel computers and clusters of workstations are considered promising platforms for numerical scientific computing. This paper describes the first distributed-memory implementation of the split-merge algorithm, an eigenvalue solver for symmetric tridiagonal matrices that uses Laguerre's iteration and exploits the separation property in order to create independent subtasks. Implementations of the split-merge algorithm on both an nCUBE-2 hypercube and a cluster of Sun Spare-10 workstations are described, with emphasis on load balancing, communication overhead, and interaction with other user processes. A performance study demonstrates the advantage of the new algorithm over a parallelization of the well-known bisection algorithm. A comparison of the performance of the nCUBE-2 and cluster implementations supports the claim that workstation clusters offer a cost-effective alternative to massively parallel computers for certain scientific applications.
School psychology in the U.S.: A quantitative survey

Abstract Thirty-two states and the District of Columbia responded to a survey on their school psychology services programs in the period 1966–1974. Ratios of workers to students averaged 1 to 21,900 in the base period, improving to 1 to 8,100 by school year 1974–1975. Rates of growth and rankings are given by state, as well as projected goals for responding states.
Policy: a call for global nuclear disarmament.

Danger from nuclear weapons is mounting. It is time to take control of the nuclear fuel cycle and move towards a world without warheads, says Scott D. Sagan.
The effect of chromium implantation on the hardness, elastic modulus, and residual stress of Al2O3

Abstract A mechanical properties microprobe was used to obtain the values of hardness and elastic modulus for a-axis and c-axis oriented single crystals of sapphire implanted with chromium (150 to 180 keV) at room temperature. Implantation caused an increase in the hardness with no detectable effect on the modulus. The effect of implantation on the apparent yield effect exhibited by nearly perfect single crystals is discussed. The residual surface compressive stresses produced by these implantations, as determined by an indentation technique, ranged from 650 to 1320 MPa.
Synthesis of 3',5'-Dipeptidyl Oligonucleotides.

Peptide−DNA hybrids are richly functionalized analogues of biomolecules that may have applications as hybridization probes and antisense agents with tunable binding and targeting properties. So far...
Heterogeneous Nuclear Ribonucleoproteins H and F Regulate the Proteolipid Protein/DM20 Ratio by Recruiting U1 Small Nuclear Ribonucleoprotein through a Complex Array of G Runs

In this study, we sought to investigate the mechanism by which heterogeneous nuclear ribonucleoprotein (hnRNP) H and F regulate proteolipid protein (PLP)/DM20 alternative splicing. G-rich sequences in exon 3B, G1 and M2, are required for hnRNPH- and F-mediated regulation of the PLP/DM20 ratio and, when placed between competing 5′ splice sites in an α-globin minigene, direct hnRNPH/F-regulated alternative splicing. In contrast, the activity of the intronic splicing enhancer, which is necessary for PLP splicing, is only modestly reduced by removal of hnRNPH/F both in PLP and α-globin gene context. In vivo, hnRNPH reversed reduction of DM20 splicing induced by hnRNPH/F removal, whereas hnRNPF had little effect. Tethering of the MS2-hnRNPH fusion protein downstream of the DM20 5′ splice site increased DM20 splicing, whereas MS2-hnRNPF did not. Binding of U1 small nuclear ribonucleoprotein (U1snRNP) to DM20 is greatly impaired by mutation of G1 and M2 and depletion of hnRNPH and F. Reconstitution of hnRNPH/F-depleted extracts with either hnRNPH or F restored U1snRNP binding. We conclude that hnRNPH and F regulate DM20 splicing by recruiting U1snRNP and that hnRNPH plays a primary role in DM20 splice site selection in vivo. Decreased expression of hnRNPH/F in differentiated oligodendrocytes may regulate the PLP/DM20 ratio by reducing DM20 5′ splice site recognition by U1snRNP.
Computer generation of dense polydisperse sphere packings

We present an extension of the Lubachevsky and Stillinger [J. Stat. Phys. 60, 561 (1990)] packing algorithm to generate packings of polydisperse spheres. The original Lubachevsky–Stillinger algorithm is a nonequilibrium protocol that allows a set of monodisperse spheres to grow slowly over time eventually reaching an asymptotic maximum packing fraction. We use this protocol to pack polydisperse spheres in three dimensions by making the growth rate of a sphere proportional to its initial diameter. This allows us to specify a size distribution of spheres, which is then preserved throughout the growth process (except the mean diameter increases). We use this method to study the packing of bidisperse sphere systems in detail. The packing fractions of the configurations generated with our method are consistent with both previously generated experimental and simulated packings over a large range of volume ratios. Our modified Lubachevsky–Stillinger protocol, however, extends the range of sphere volume ratios well beyond that which has been previously considered using simulation. In doing so, it allows both small volume ratios and large volume ratios to be studied within a single framework. We also show that the modified Lubachevsky–Stillinger algorithm is appreciably more efficient than a recursive packing method.
"Extinction" of the McCollough effect does not transfer interocularly

A McCollough effect was induced in subjects by having them view typical adapting stimuli binocularly for 5 min. In the control condition, the strength of the McCollough effect was measured 20 min after the end of the adaptation. The strength was measured during monocular and binocular viewing of a test pattern via a color cancellation technique. Monocular strengths for the two eyes of a given subject were equal to each other and slightly weaker than the binocular strength. In the test condition, 15 min of the 20 min between adaptation and testing were spent monocularly viewing black and white gratings of the same orientation and spatial frequency as the adapting gratings. The strength of the effect as measured ipsilaterally was markedly decreased from that in the control condition. The strength of the effect as measured with the contralateral eye showed only a small decrease from that of the control condition. This finding is relevant to various models of the McCollough effect and related color aftereffects, especially those that posit a “learning” type of mechanism between achromatic spatial channels (which exhibit clear interocular transfer of various achromatic effects) and monocular color channels.
Global stability for homothetic preferences in a distribution economy

Abstract It is shown that despite the fact that in general the existence of a representative consumer does not imply global stability, the assumption of homothetic preferences does imply global stability in the case of a distribution economy.
Motorische hörstummheit und parietale Aphasie Zugleich eine Frage nach der Plastizität des Gehirns

Zusammenfassung In manchen Fallen von Horstummheit liegt eine ideokinetische Form motorischer Aphasie, d.h. eine parietale Aphasie vor, wie man nach dem genaueren Bild feststellen kann. Die Unfahigkeit der Kinder, das Sprechen jemals vollkommen zu erlernen, obwohl sie sprachlich alles verstehen und Einzellaute richtig bilden, zeigt, dass die Plastizitat des Gehirns auch in der fruhen Kindheit begrenzt ist. Bestimmte Funktionen im Bereich des Sprachvorgangs konnen ohne ein bestimmtes umschriebenes Hirngebiet nicht zustandekommen. Im Parietallappen liegt in Bezug auf die Sprache eine solche Zentralstelle.
Effects of Peer Support Interventions on Students' Access to the General Curriculum and Social Interactions.

Peer support interventions are emerging as an effective alternative to traditional paraprofessional models for assisting students with moderate to severe disabilities to access the general curriculum. To contribute to the refinement of peer support interventions, we evaluated the impact of altering the number of participating peers on the social and academic outcomes of students with and without disabilities. Our findings indicated that changes in the configuration of peer support arrangements differentially affected student outcomes. Specifically, higher levels of social interaction and contact with the general curriculum were observed when students with disabilities worked with two peers relative to one peer. The additive benefits of a second peer provide guidance to educators concerning the implementation of peer support interventions in inclusive classrooms.
Introduction to the Symposium

January 25, 1995, is the 50th anniversary of the first controlled addition of fluoride to a public water supply. Those 50 years have seen extraordinary advances in oral health and consequent quality of life, for which fluoride use is generally considered the primary reason. More extensive exposure to fluoride in the modern era, however, has led to both a continuing decline in caries experience and an increased prevalence of dental fluorosis in children. At the other end of life, fluoride's role in bone strength among older people is not well defined. This symposium examines several aspects of fluoride use in the United States today, and has the purpose of helping to define the balance between maximizing the benefits of fluoride while minimizing its undesirable side effects.
Spinal cord sarcoidosis

Three patients with spinal cord involvement by sarcoid are described and the literature is reviewed. Fifteen patients with histologically verified sarcoidosis involving the spinal cord presented with progressive myelopathy due to tumor. Myelography variously showed an extramedullary intradural mass; an intramedullary mass; a thinned, atrophic cord; or normal configuration. Although laminectomy and biopsy are often required to establish the diagnosis, treatment is medical, using corticosteroid drugs. Treatment seldom leads to complete recovery, but neurological deficits may stabilize or improve.
Neurological suppression of diaphragm electromyographs in hamsters infected with West Nile virus.

To address the hypothesis that respiratory distress associated with West Nile virus (WNV) is neurologically caused, electromyographs (EMGs) were measured longitudinally from the diaphragms of alert hamsters infected subcutaneously (s.c.) with WNV. The EMG activity in WNV-infected hamsters was consistently and significantly (P ≤ .001) less than that of sham-infected animals, beginning with suppression at day 3 and continuing to beyond day 17 after viral challenge. Of the tissues known to affect respiration, i.e., lung, diaphragm, cervical spinal cord, brain stem, and the carotid or aortic bodies, foci of WNV-immunoreactive neurons were only observed in the brain stems and some cervical spinal cords from EMG-suppressed animals. To confirm the involvement of the brain stem and spinal cord, WNV was injected directly in the ventrolateral medulla containing respiratory functions using stereotaxic surgery and into the cervical cord at the C4 vertebral level. As with subcutaneous WNV challenge, hamsters developed EMG suppression of the diaphragm within 4 days. Because WNV-positive neurons were only sporadically identified in EMG-suppressed animals as early as day 3, a plausible mechanism of EMG suppression may involve regulation of diaphragm activity via vagal afferents acting on respiratory control system neurons in the brain stem. Brain auditory evoked response (BAER) was performed to determine if generalized brain stem neuropathy was the cause of diaphragmatic EMG suppression. Because deficiencies of BAER were only observed after day 11, which is long after diaphragm EMGs became suppressed, multiple phases of WNV-induced neurological disease are likely. These data establish that WNV infection of hamsters causes electrophysiological suppression of the diaphragm either directly by lesions in the brain stem and cervical spinal cord, or indirectly by altered vagal afferent function. This WNV-induced EMG suppression may be analogous to conditions leading to respiratory distress of WNV-infected human patients.
Malignant Pleural Effusions: Management Options With Consideration of Coding, Billing, and a Decision Approach

Malignant pleural effusions (MPEs) are a troublesome and debilitating complication of advanced malignancies, with > 150,000 cases in the United States each year. The standard management approach begins with a diagnostic and/or therapeutic thoracentesis. Should the MPE recur, a more definitive management strategy is often undertaken with several approaches available to the chest physician or surgeon. These options include repeat thoracentesis, tube thoracostomy with chemical pleurodesis, placement of an indwelling cuffed, tunneled pleural catheter with or without pleurodesis, or medical pleuroscopy or video-assisted thoracoscopic surgery with pleurodesis. Each approach has unique advantages, disadvantages, and likelihood of successful symptom relief and pleurodesis. This article will provide a general review of MPE management strategies including information concerning coding, billing, documentation, and a decision approach among these various methods.
Neural circuitry underlying perception of duration depends on language experience

Thai, a language which exhibits a phonemic opposition in vowel length, allows us to compare temporal patterns in linguistic and nonlinguistic contexts. Functional MRI data were collected from Thai and English subjects in a speeded-response, selective attention paradigm as they performed same/different judgments of vowel duration and consonants (Thai speech) and hum duration (nonspeech). Activation occurred predominantly in left inferior prefrontal cortex in both speech tasks for the Thai group, but only in the consonant task for the English group. The Thai group exhibited activation in the left mid superior temporal gyrus in both speech tasks; the English group in the posterior superior temporal gyrus bilaterally. In the hum duration task, peak activation was observed bilaterally in prefrontal cortex for both groups. These crosslinguistic data demonstrate that encoding of complex auditory signals is influenced by their functional role in a particular language.
In vivo neural stem cell imaging: current modalities and future directions.

Neural stem cells have been proposed as a promising therapy for treating a wide variety of neuropathologies. While several studies have demonstrated the therapeutic benefits of neural stem cells, the exact mechanism remains elusive. In order to facilitate research efforts to understand these mechanisms, and before neural stem cell-based therapies can be utilized in a clinical context, we must develop means of monitoring these cells in vivo. However, because of tissue depth and the blood–brain barrier, in vivo imaging of neural stem cells in the brain has unique challenges that do not apply to stem cells for other purposes. In this paper, we review contemporary methods for in vivo neural stem cell imaging, including MRI, PET and optical imaging techniques.
Describing Teachers' Conceptual Ecologies for the Nature of Science

This research focused on the interactionist conceptual ecologies of inservice teachers and how these ecologies influenced these teachers' conceptual frameworks for the nature of science (NOS). The participants in the study were five teachers enrolled in a graduate course focused on NOS. Data included participants' responses to open-ended and Likertscalesurveys,interviews,writingprompts,andparticipantobservationsofclassroom sessions. We propose a model of the interaction of the prominent components of teachers' conceptual ecologies for NOS, one in which learning dispositions, understandings of the broadenterpriseofscience,andorientationtolearningandlearnersareunderstoodtoshape teachers' conceptual frameworks for NOS. The complex ties between NOS conceptions and goals, affect, dispositions, and beliefs speak to the inclusion of the bounded nature of science as a central aspect of NOS for practicing teachers. Teachers' dispositions toward learningthisconstructarelinkedtotheirconceptionsoftheboundariesofscienceaswellas their understanding of the role of NOS in their own teaching. We argue that a recognition of the bounded nature of science foregrounds actions of a teacher's learning disposition, thus potentially minimizing the influence of their religious beliefs. C
Spectrum Load Balancing for Medium Access in Cognitive Radio Systems

In this work, the problem of spectrum allocation in cognitive radios is shown to be similar to the load balancing problem in distributed computer systems. Spectrum load balancing (SLB) algorithm based on the non-cooperative load balancing problem in computers is proposed, and is applied to a cognitive radio system. The capability of SLB to support QoS in the presence of other competing cognitive networks is evaluated via simulations and compared with the existing spectrum load smoothing (SLS) algorithm. SLB is more efficient than SLS and it provides a Nash equilibrium.
Physiologic Pulsatile Flow Bioreactor Conditioning of Poly(ethylene glycol)-based Tissue Engineered Vascular Grafts

Mechanical conditioning represents a potential means to enhance the biochemical and biomechanical properties of tissue engineered vascular grafts (TEVGs). A pulsatile flow bioreactor was developed to allow shear and pulsatile stimulation of TEVGs. Physiological 120 mmHg/80 mmHg peak-to-trough pressure waveforms can be produced at both fetal and adult heart rates. Flow rates of 2 mL/sec, representative of flow through small diameter blood vessels, can be generated, resulting in a mean wall shear stress of approximately 6 dynes/cm(2) within the 3 mm ID constructs. When combined with non-thrombogenic poly(ethylene glycol) (PEG)-based hydrogels, which have tunable mechanical properties and tailorable biofunctionality, the bioreactor represents a flexible platform for exploring the impact of controlled biochemical and biomechanical stimuli on vascular graft cells. In the present study, the utility of this combined approach for improving TEVG outcome was investigated by encapsulating 10T-1/2 mouse smooth muscle progenitor cells within PEG-based hydrogels containing an adhesive ligand (RGDS) and a collagenase degradable sequence (LGPA). Constructs subjected to 7 weeks of biomechanical conditioning had significantly higher collagen levels and improved moduli relative to those grown under static conditions.
Measurement of Pore Characteristics in Nonwoven Fabrics Using Image Analysis

In evaluating the performance of nonwoven fabrics, pore characteristics provide important information concerning fluid permeability, filtration and mechanical properties of the fabrics. This paper reports new approaches of measuring pore characteristics using image analysis. The image processing techniques for identifying pore regions are addressed. The image analysis techniques are presented for pore characterization from four aspects: size, shape, orientation and placement. A new approach to estimate parameters of a theoretical model proposed by Lombard, et al. (1989) for prediction of pore size distribution is also introduced. Two sets of nonwoven fabrics with different fiber contents and different weights per unit area are investigated using these techniques.
Total body irradiation as treatment for lymphosarcoma

Abstract This study reports on 64 cases of advanced lymphocytic lymphoma treated by Total Body Irradiation (TBI). Of these, 40 received TBI as their initial and only primary therapy. There were 29 cases of nodular histology and 11 cases of diffuse histology according to the Rappaport 6 criteria. Treatment comprised 15 rad given twice weekly to a total dose of 150 rad. Persistent local masses were given additional local boost irradiation. Patients experienced no significant morbidity, and toxicity was confined to thrombocytopenia; 40% of patients required interruption in the treatment course to allow platelet count recovery. Complete responses were seen in 80% of 40 patients who were primarily treated, for a median survival of more than 32 months and 83% actuarial survival at 3 years. TBI appears to be an effective therapy in advanced lymphosarcoma. It should be considered a systemic agent and deserves further investigation in combination with chemotherapeutic agents.
High velocity dislocation motion and interatomic force law

Abstract The effect of the interatomic force law on the motion of a dislocation in a simple cubic crystal is investigated. Earlier work on the snapping bond model is extended to include a piecewise linear force law. Consistency conditions are obtained for atomic displacements that lie outside the range of Hooke's law (bond strain less than β). The conditions are solved analytically for small deviations from the snapping bond model [β ≈ ( 1 2 )] and numerically for a larger range of β. We obtain self consistent solutions for most of the dislocation velocity range. For ν > 0.7 the solutions do not differ markedly from those of the snapping bond model. For ν
The Developmentally Regulated alb1 Gene of Aspergillus fumigatus: Its Role in Modulation of Conidial Morphology and Virulence

Aspergillus fumigatus, an important opportunistic pathogen which commonly affects neutropenic patients, produces conidia with a bluish-green color. We identified a gene, alb1, which is required for conidial pigmentation. The alb1 gene encodes a putative polyketide synthase, and disruption of alb1 resulted in an albino conidial phenotype. Expression of alb1 is developmentally regulated, and the 7-kb transcript is detected only during the conidiation stage. The alb1 mutation was found to block 1,3,6,8-tetrahydroxynaphthalene production, indicating that alb1 is involved in dihydroxynaphthalene-melanin biosynthesis. Scanning electron microscopy studies showed that the alb1 disruptant exhibited a smooth conidial surface, whereas complementation of the alb1 deletion restored the echinulate wild-type surface. Disruption of alb1 resulted in a significant increase in C3 binding on conidial surfaces, and the conidia of the alb1 disruptant were ingested by human neutrophils at a higher rate than were those of the wild type. The alb1-complemented strain producing bluish-green conidia exhibited inefficient C3 binding and neutrophil-mediated phagocytosis quantitatively similar to those of the wild type. Importantly, the alb1 disruptant had a statistically significant loss of virulence compared to the wild-type and alb1-complemented strains in a murine model. These results suggest that disruption of alb1 causes pleiotropic effects on conidial morphology and fungal virulence.
Change in Hepatitis A Seroprevalence among U.S. Children and Adolescents: Results from the National Health and Nutrition Examination Survey 2003-2006 and 2007-2010.

To examine changes in seroprevalence of antibodies to hepatitis A virus (HAV) during a period in which universal vaccine recommendations for all U.S. children were implemented, results from serologic testing from the National Health and Nutrition Examination Survey (NHANES) from 2003–2010 were analyzed among 7,989 participants age 6–19 years, born in the U.S. in two birth cohorts (1986–1996 and 1997–2004). Overall prevalence increased over time from 24.4% in 2003–2006 to the highest ever reported (37.6%) in 2007–2010. Specifically, increases reached statistical significance in the birth cohort born in the years after implementation of vaccine recommendations (1997–2004), among those of race/ethnicity other than white, non-Hispanic, and among states where recommendations were implemented later. The greatest increase over time was among the subgroup of persons in states with early implementation who were of race/ethnicity other than white, non-Hispanic. Geographic region and birth cohort based on vaccine recommendations as well as race/ethnicity were the main predictors of seropositivity in 2007–2010. The increase in Hepatitis A seroprevalence occurred during a time of decreasing incidence and increasing vaccination, however race/ethnic disparities persist.
Spectral analysis of heart rate variability using breathing bursts as a time base

Diaphragmatic EMG burst activity is analyzed by means of waveform recognition, yielding a nonlinear time scale where the interval between each EMG burst is taken as one time period. The heart-rate variability data are then suitably interpolated to yield a pseudotime data series with respect to the EMG time base. Spectral analysis of the interpolated EKG rate data reveals a harmonic mode associated with breathing, but with substantially reduced peak width. Using this procedure, the EKG spectrum is averaged over long periods with little peak broadening due to changes in breathing rate. >
Optimal energy allocation for delay-constrained data transmission over a time-varying channel

We seek to maximize the data throughput of an energy and time constrained transmitter sending data over a fading channel. The transmitter has a fixed amount of energy and a limited amount of time to send data. Given that the channel fade state determines the throughput obtained per unit of energy expended, the goal is to obtain a policy for scheduling transmissions that maximizes the expected data throughput. We develop a dynamic programming formulation that leads to an optimal closed-form transmission schedule. We then extend our approach to the problem of minimizing the energy required to send a fixed amount of data over a fading channel given deadline constraints.
Estimating competition coefficients: strong competition among three species of frugivorous flies.

Despite the abundance of studies on competitive interactions, relatively few experiments have been used to fit explicit competition models and estimate competition coefficients. Such estimates are valuable for making contact between theoretical and empirical studies, which tend to measure competition in different units. To quantify the strength of competitive interactions among the larvae of three species of frugivorous flies, I manipulated the densities of each species to investigate all three pairwise interactions. The densities of each species were changed independently (i.e., using a response surface experimental design), which allowed maximum likelihood estimation of the competition coefficients for each species, based on the Hassell and Comins competition model. The effects of competitor density on larval survival, time to emergence, and the weight of emerging adults were also analyzed to investigate the responses of individual species to density. The estimates of the competition coefficients suggest that the larvae of these flies experience strong asymmetric competition for resources, and raise questions as to how these species coexist. For each pair, one of the species was largely unaffected by interspecific competition, but decreased the performance of the other.
Initial UK public reaction to avian influenza: Analysis of opinions posted on the BBC website

In February 2007, avian influenza arrived in the UK. Following evidence of illness at a turkey farm in Suffolk, around 160,000 birds were slaughtered and poultry movement controls were imposed. Given past food crises (e.g. BSE), it was clearly important to predict UK public response: for example, was mass panic imminent, or would the public respond calmly? Unfortunately, there is currently no theory that enables accurate prediction of public response to novel hazards or to novel manifestations of old hazards (Hawkes and Rowe in press). Furthermore, the speed of the outbreak, and the lack of academic preparedness, undermined social scientists' ability to acquire significant timely data on public perceptions in order to aid theory development or inform policy making. Analysis of initial public opinion is, however, possible, thanks to the recording of responses to open questions about this incident posted on the British Broadcasting Corporation's (BBC) website. In this paper we: (a) justify the relevance and...
Evidence of preserved endothelial function and vascular plasticity with age

We sought to identify the relationship between shear stimuli and flow-mediated vasodilation and to determine whether small muscle mass exercise training could provoke limb-specific improvements in ...
Functional effects of central core disease mutations in the cytoplasmic region of the skeletal muscle ryanodine receptor.

Central core disease (CCD) is a human myopathy that involves a dysregulation in muscle Ca2+ homeostasis caused by mutations in the gene encoding the skeletal muscle ryanodine receptor (RyR1), the protein that comprises the calcium release channel of the SR. Although genetic studies have clearly demonstrated linkage between mutations in RyR1 and CCD, the impact of these mutations on release channel function and excitation-contraction coupling in skeletal muscle is unknown. Toward this goal, we have engineered the different CCD mutations found in the NH2-terminal region of RyR1 into a rabbit RyR1 cDNA (R164C, I404M, Y523S, R2163H, and R2435H) and characterized the functional effects of these mutations after expression in myotubes derived from RyR1-knockout (dyspedic) mice. Resting Ca2+ levels were elevated in dyspedic myotubes expressing four of these mutants (Y523S > R2163H > R2435H R164C > I404M RyR1). A similar rank order was also found for the degree of SR Ca2+ depletion assessed using maximal concentrations of caffeine (10 mM) or cyclopiazonic acid (CPA, 30 μM). Although all of the CCD mutants fully restored L-current density, voltage-gated SR Ca2+ release was smaller and activated at more negative potentials for myotubes expressing the NH2-terminal CCD mutations. The shift in the voltage dependence of SR Ca2+ release correlated strongly with changes in resting Ca2+, SR Ca2+ store depletion, and peak voltage–gated release, indicating that increased release channel activity at negative membrane potentials promotes SR Ca2+ leak. Coexpression of wild-type and Y523S RyR1 proteins in dyspedic myotubes resulted in release channels that exhibited an intermediate degree of SR Ca2+ leak. These results demonstrate that the NH2-terminal CCD mutants enhance release channel sensitivity to activation by voltage in a manner that leads to increased SR Ca2+ leak, store depletion, and a reduction in voltage-gated Ca2+ release. Two fundamentally distinct cellular mechanisms (leaky channels and EC uncoupling) are proposed to explain how altered release channel function caused by different mutations in RyR1 could result in muscle weakness in CCD.
Pathology of upper respiratory tract disease of gopher tortoises in Florida.

Between August 1993 and September 1995, 24 gopher tortoises (Gopherus polyphemus) were received for pathological evaluations from various locations in Florida (USA). All tortoises were examined for clinical signs of upper respiratory tract disease (URTD) including nasal and ocular discharge, palpebral edema, and conjunctivitis. Of the 24 tortoises, 10 had current or previously observed clinical signs of URTD and 14 did not. A blood sample was drawn for detection of anti-mycoplasma antibodies by ELISA, and nasal lavage samples were collected for culture and detection of Mycoplasma agassizii gene sequences by polymerase chain reaction (PCR). Of the 14 clinically healthy tortoises, eight were sero-, culture- and PCR-negative, and six were seropositive for antibodies against M. agassizii. Of those six, five were culture- and/or PCR-positive for M. agassizii, and one was culture- and PCR-negative. Of the 10 ill tortoises, nine were seropositive by the ELISA and one was in the suspect range. Nine of the ill tor...
Some Practical Examples of Computer‐Adaptive Sequential Testing

Computerized testing has created new challenges for the production and administration of test forms. Many testing organizations engaged in or considering computerized testing may find themselves changing from well-established procedures for handcrafting a small number of paper-and-pencil test forms to procedures for mass producing many computerized test forms. This paper describes an integrated approach to test development and administration called computer-adaptive sequential testing, or CAST. CAST is a structured approach to test construction which incorporates both adaptive testing methods with automated test assembly to allow test developers to maintain a greater degree of control over the production, quality assurance, and administration of different types of computerized tests. CAST retains much of the efficiency of traditional computer adaptive testing (CAT) and can be modified for computer mastery testing (CMT) applications. The CAST framework is described in detail and several applications are demonstrated using a medical licensure example.