cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of polyamine analogues and inhibition of polyamine oxidase on spermidine/spermine N1-acetyltransferase activity and cell proliferation

Abstract Several bis(ethyl)polyamine analogues are currently undergoing trials as antitumor agents. The ability of some of these analogues to induce spermidine/spermine N 1 -acetyltransferase and to inhibit cell proliferation was examined in a number of different cell lines. Although N 1 , N 11 bis(ethyl)norspermine was a potent inducer of the acetylase in all cell lines tested, there was a striking difference in the acetylase induction in response to N 1 ,N 11 -bis(ethylamino)propyl]-1,7-heptanediamine. This was a very strong inducer in CHO cells but had no effect in HT29 cells and very little effect in COS-7 or L1210 cells. There was no correlation between the induction of the acetylase and the ability of these analogues to inhibit cell proliferation since N 1 , N 11 -bis(ethylamino)-propyl]-1,7-heptanediamine was as at least as strongly antiproliferative as N 1 , N 11 -bis(ethyl)-norspermine or N 1 , N 12 -bis(ethyl)spermine. Acetylase induction and the intracellular level of the analogues were increased in CHO cells by treatment with a polyamine oxidase inhibitor suggesting that they are degraded by polyamine oxidase. The absence of polyamine oxidase in some tumors may therefore contribute to their sensitivity to these analogues.
The (Amorphous) Anatomy of an Invention The Case of Magnetic Resonance Imaging (MRI)

The priority dispute between Raymond Damadian and Paul Lauterbur over the 'invention' of magnetic resonance imaging (MRI) has attracted the attention of social and natural scientists for more than 30 years. In this paper, I have used this priority dispute to analyze the complex socio-epistemic processes through which a claim for an invention is made and strengthened. I argue that a tension exists because techno-scientific practices are embedded within a particular disciplinary regime of authorship: even though techno-scientific practices occur through distributed cognition and are contingent upon particular socio-epistemic contexts, a claim for an invention requires assigning authorship to a particular person, company, or institution in order to clearly define the origin and the novelty of that particular techno-scientific event. Nevertheless, the outcomes of socio-epistemic practices for making and strengthening priority claims are shifting, open-ended, and contingent upon particular socio-epistemic contexts.
PHOTOSYNTHETIC AND HETEROTROPHIC IMPACTS OF NUTRIENT LOADING TO BLACKWATER STREAMS

Blackwater stream systems are the most abundant type of freshwater lotic system on the Coastal Plain of the eastern United States. Many of these ecosystems drain watersheds that receive large anthropogenic nutrient inputs, whereas some blackwater systems remain relatively pristine. A series of nutrient addition experiments was carried out over a four-year period to assess the roles of nitrogen and phosphorus loading on the phytoplankton, bacterioplankton, and respiration of two third-order and two fifth-order blackwater streams in southeastern North Carolina. Stream water was distributed into 4-L containers, amended with various nutrient addition treatments, and incubated in gently agitated outdoor pools over a six-day period. Chlorophyll a production, direct bacterial counts, ATP, and biochemical oxygen demand (BOD) were measured as response variables. Significant phytoplankton production over control occurred in most experiments involving nitrogen additions, regardless of whether it was in the form of a...
Dynamic strain aging in carbide strengthened molybdenum alloys

A study was made of the dynamic strain aging processes in carbide strengthened molybdenum alloys. Strengthening due to dynamic strain aging was observed in the temperature range 1500° to 2400°F. The strengthening is believed to arise from the pinning of mobile dislocations by metal-carbon pairs or clusters and/or carbide precipitates. This immobilization of the dislocations led to a high work hardening rate and the observed strengthening.
Male responses to direct verbal sexual initiatives of females

Abstract The use of direct verbal sexual initiative by females and its reported effect on male partners were examined employing a sample of college students. It was found that over one‐half of the females reported directly asking for sex. These women were no more likely to report being rebuffed by their male partners than those not employing direct means. Additionally, females asking directly were found to be generally less conventional, more assertive, more likely to be involved with males who also use explicit means of asking for sex and whom they regarded as able to cope with direct female requests. On the other hand, males tended to report compliance with their female partner's request for sex whether direct or indirect. When sex occasionally did not occur when requested, very few individuals reported the type of approach of self or other as the main reason for noncompliance. Finally, the evidence indicates a generalized belief among the females that males may be “turned off” by female sexual assertiv...
Ocular diurnal rhythms and eye growth regulation: Where we are 50 years after Lauber

Many ocular processes show diurnal oscillations that optimize retinal function under the different conditions of ambient illumination encountered over the course of the 24 h light/dark cycle. Abolishing the diurnal cues by the use of constant darkness or constant light results in excessive ocular elongation, corneal flattening, and attendant refractive errors. A prevailing hypothesis is that the absence of the Zeitgeber of light and dark alters ocular circadian rhythms in some manner, and results in an inability of the eye to regulate its growth in order to achieve emmetropia, the matching of the front optics to eye length. Another visual manipulation that results in the eye growth system going into a "default" mode of excessive growth is form deprivation, in which a translucent diffuser deprives the eye of visual transients (spatial or temporal) while not significantly reducing light levels; these eyes rapidly elongate and become myopic. It has been hypothesized that form deprivation might constitute a type of "constant condition" whereby the absence of visual transients drives the eye into a similar default mode as that in response to constant light or dark. Interest in the potential influence of light cycles and ambient lighting in human myopia development has been spurred by a recent study showing a positive association between the amount of time that children spent outdoors and a reduced prevalence of myopia. The growing eyes of chickens and monkeys show a diurnal rhythm in axial length: Eyes elongate more during the day than during the night. There is also a rhythm in choroidal thickness that is in approximate anti-phase to the rhythm in eye length. The phases are altered in eyes growing too fast, in response to form deprivation or negative lenses, or too slowly, in response to myopic defocus, suggesting an influence of phase on the emmetropization system. Other potential rhythmic influences include dopamine and melatonin, which form a reciprocal feedback loop, and signal "day" and "night" respectively. Retinal dopamine is reduced during the day in form deprived myopic eyes, and dopamine D2 agonists inhibit ocular growth in animal models. Rhythms in intraocular pressure as well, may influence eye growth, perhaps as a mechanical stimulus triggering changes in scleral extracellular matrix synthesis. Finally, evidence shows varying influences of environmental lighting parameters on the emmetropization system, such as high intensity light being protective against myopia in chickens. This review will cover the evidence for the possible influence of these various factors on ocular growth. The recognition that ocular rhythms may play a role in emmetropization is a first step toward understanding how they may be manipulated in treatment therapies to prevent myopia in humans.
The Relevance of Person-Centered Ethnography to Cross-Cultural Psychiatry

In this article the relevance of person-centered ethnography to cross-cultural psychiatry is discussed. The term person-centered ethnography is first defined, the historical development of this line of anthropological research is traced, and how and why it might be used in cross-cultural psychiatry is examined. Following this introduction current developments in person-centered ethnography are reviewed, while focusing especially on the strengths and limitations of different styles and approaches. General trends and new directions in the field are addressed, rather than examining or referring to details of particular studies.
Apoptosis of ovarian granulosa cells: correlation with the reduced activity of ERK-signaling module.

Apoptosis of the ovarian granulosa cells plays a crucial role in the determination of the number of follicles destined to ovulate in each reproductive cycle. While the activation of specific apoptotic pathway or the inactivation of cell survival pathway can initiate apoptosis, the signaling mechanism(s) involved in initiating the onset of apoptosis in granulosa cells is not fully understood. In the present study, using granulosa cells derived from eCG-primed immature rats, we investigated the temporal signaling events involved in the onset of apoptosis in the granulosa cells. The administration of 15 IU of eCG to 21-day-old immature female rats stimulate the growth and development of ovarian follicles until 72 h, after which the granulosa cells of the ovarian follicles undergo apoptosis due to the waning levels of tropic hormonal support. An analysis of the signaling events leading to apoptosis indicates that the DNA fragmentation can be seen in these cells from 96 h. A small increase in the levels of the pro-apoptotic factor Bax can be seen from 96 h while an increase in the activity of JNK can be seen from 108 h onwards. By contrast, a reduction in ERK signaling can be seen by 48 h. Similar reduction in Raf-1 kinase activity can be discerned from 48 h onwards. A concomitant decrease in the phosphorylated form of Bad can also be detected. These findings taken together, suggest that the loss of tropic hormone support is translated into the attenuation of Raf-1-MEK-ERK signaling pathway and this reduction along with a reduction in the levels of phosphorylated form of Bad triggers the onset of apoptosis in the ovarian granulosa cells. J. Cell. Biochem. 75:547–554, 1999. © 1999 Wiley-Liss, Inc.
An operator theory of parametric programming for the transportation problem‐II

This paper investigates the effect on the optimum solution of a (capacitated) transportation problem when the data of the problem (the rim conditions-i. e., the warehouse supplies and market demands-the per unit transportation costs and the upper bounds) are continuously varied as a (linear) function of a single parameter. An operator theory is developed and algorithms provided for applying rim and cost operators that effect the transformation of optimum solution associated with changes in rim conditions and unit costs. Bound operators that effect changes in upper bounds are shown to be equivalent to rim operators. The discussion in this paper is limited to basis preserving operators for which the changes in the data are such that the optimum basis structures are preserved.
Rubber band ligation for hemorrhoidal disease can be safely performed in select HIV-positive patients

PURPOSE: Many surgeons have abandoned the use of rubber band ligation for the treatment of hemorrhoids in patients infected with human immunodeficiency virus because of the belief that this procedure could lead to disastrous outcomes. This study was designed to evaluate the safety and efficacy of rubber band ligation in otherwise healthy human immunodeficiency virus-positive patients. METHODS: A retrospective chart review of healthy human immunodeficiency virus-positive patients who underwent rubber band ligation for symptomatic hemorrhoids between April 1993 and May 2000 was conducted. RESULTS: The study group comprised 11 patients. All patients were male, with a median age of 48 (range, 32–64) years. Mean T-cell helper count was 450 (range, 200–1,000) cells/µl. A median of 2 (range, 1–4) rubber band ligations were performed per patient. The median length of follow-up was seven (range, 1–28) months. There were no deaths or complications in any study group patient. Eight patients (73 percent) had excellent results, with complete resolution of symptoms. Two patients (18 percent) had initial improvement but subsequently had hemorrhoidectomy because of recurrent symptoms. Only one patient (9 percent) had no benefit from rubber band ligation and underwent hemorrhoidectomy. CONCLUSION: These data suggest that asymptomatic human immunodeficiency virus-positive patients can be treated safely and effectively with rubber band ligation for symptomatic hemorrhoids.
Radio Astronomical Constraints on Coronal Heating by High-Frequency Alfvén Waves

It has been suggested that the heating of the solar corona and the acceleration of the solar wind to their observed values are due to high-frequency (1 to several hundred Hertz) magnetohydrodynamic (MHD) waves. This suggestion circumvents well-established difficulties with heating and acceleration by observed, low-frequency (milliHertz) MHD waves. There is no widely accepted mechanism for damping the low-frequency waves, and their observed amplitude throughout the inner heliosphere is insufficient to account for observed solar wind properties. By contrast, the alleged high-frequency waves would not be detected by radio propagation observations (specifically Faraday rotation observations) hitherto conducted, so the amplitude of these waves would appear to be a free parameter for the theories. The purpose of this paper is to show that these putative waves might reveal themselves through another observable radio propagation phenomenon, Faraday screen depolarization. Faraday screen depolarization is a reduction of the observed degree of linear polarization of an extended, polarized radio source when viewed through a medium (here referred to as a screen) in which the Faraday rotation varies in a random fashion. Expressions for Faraday screen depolarization are extracted from the literature and calculations appropriate to the solar corona and inner solar wind are made. Depending on the exact properties of the high-frequency turbulence, a detectable (i.e. ~5%-20%) depolarization could result. We present six polarimetric observations at a frequency of 1465 MHz of polarized sources observed close to the Sun with the Very Large Array radio telescope in 1997. These observations show no detectable depolarization and rule out some turbulence models. The existing observations are far from being definitive in ruling out high-frequency turbulence with the required properties. However, additional observations, particularly undertaken at lower radio frequencies, could furnish far more restrictive limits.
Patterns of diagnostic testing in the academic setting: The influence of medical attendings' subspeciality training

Internists with subspecialty training (subspecialists) constitute the majority of the medical faculty members and the test-ordering behavior of these subspecialists influences how house officers and students solve clinical problems. To assess whether test-ordering patterns are influenced by the ward attendings' subspecialty status, we identified the number of gastrointestinal endoscopic procedures, bone marrow procedures and exercise stress tests that were ordered on 9608 patients admitted to a medical service during a 3 year period. The patient management was supervised by attendings, 8 of whom were generalists and 37 of whom were subspecialists. House officers supervised by generalists ordered 23% fewer gastrointestinal procedures, 47% fewer bone marrow procedures, 43% fewer exercise stress tests and 29% fewer total procedures than house staff supervised by subspecialists (P—not significant, P < 0.001, P < 0.05 and P < 0.01, respectively). House officers perceive a difference between the test-ordering patterns of subspecialists and generalists. They attribute this difference to post-residency training and believe that the use of more tests indicates a greater compulsion toward an exhaustive evaluation.
Aerial-image-based off-focus inspection: lithography process window analysis during mask inspection

The industry roadmap for IC manufacturing at design rules of 90nm and below foresees low k1-factor optical lithography at 193nm exposure wavelength. Aggressive model-based OPC are being used more and more frequently in order to achieve the extremely tight mask CD specifications required by 90nm technology node. State-of-the-art mask inspection is challenged to detect CD defects close to metrology resolution. Inspection of OPC is critical; OPC feature dimensions are usually near or below the resolution limits of mask exposure. In addition, chrome defects can be semitransparent and change the intensity of light on the wafer. In this paper aerial-image based mask inspection is investigated and presented. The concept inspects a given mask based on its aerial image with selected wafer exposure conditions, thus “finds only defect which will print”. This paradigm shift in mask inspection philosophy provides the unique opportunities of verifying and controlling the entire aerial image generated by the inspected mask. As reticle enhancement techniques like OPC are designed to enhance the aerial image of a mask, this concept offers a comprehensive way of inspecting these techniques. The inspection is shifted from detecting every single minor change on mask to detecting what on mask could possibly impact the printing image quality on the wafer. In this paper an advanced application of aerial-image based mask inspection is discussed in more detail. As a standard, the Aera193 uses the best-focus aerial image for defect detection. From HNA mask inspection it is a well-known fact, that shifting the inspection off-focus, can provide a more sensitive detection. In the csase of aerial-image based inspection, going off-focus can be compared with lithography exposure out of focus. In other words, the lithography process window will be taken into account for defect detection. This methodology provides additional important information ·Understand process window printability of defects detected at best-focus ·Detect additional defects, which may print at the borders of the process window. This information is of extreme value for wafer lithography and may help by decisions about lithography process and mask usage. Focus of the paper is to analyze the application of aerial image-based off-focus inspection. Advanced OPC test plates are used to analyze detection at best and off-focus. The inspection results are compared to actual wafer results. Wafer lithography benefit is discussed.
Linkage of oxygen deficiency defects and rare earth concentrations in silica glass optical fiber probed by ultraviolet absorption and laser excitation spectroscopy

Ultraviolet absorption measurements and laser excitation spectroscopy in the vicinity of 248 nm provide compelling evidence for linkages between the oxygen deficiency center (ODC) and rare earth concentrations in Yb and Er-doped glass optical fibers. Investigations of YAG-derived and solution-doped glass fibers are described. For both Yb and Er-doped fibers, the dependence of Type II ODC absorption on the rare earth number density is approximately linear, but the magnitude of the effect is greater for Yb-doped fibers. Furthermore, laser excitation spectra demonstrate unambiguously the existence of an energy transfer mechanism coupling an ODC with Yb3+. Photopumping glass fibers with a Ti:sapphire laser/optical parametric amplifier system, tunable over the 225-265 nm region, or with a KrF laser at 248.4 nm show: 1) emission features in the 200-1100 nm interval attributable only to the ODC (Type II) defect or Yb3+, and 2) the excitation spectra for ODC (II) emission at ~280 nm and Yb3+ fluorescence (λ ~1.03 μm) to be, within experimental uncertainty, identical. The latter demonstrates that, when irradiating Yb-doped silica fibers between ~240 and 255 nm, the ODC (II) defect is at least the primary precursor to Yb3+ emission. Consistent with previous reports in the literature, the data show the ODC (II) absorption spectrum to have a peak wavelength and breadth of ~246 nm and ~19 nm (FWHM). Experiments also reveal that, in the absence of Yb, incorporating either Al2O3 or Y2O3 into glass fibers has a negligible impact on the ODC concentration. Not only do the data reported here demonstrate the relationship between the ODC (II) number density and the Yb doping concentration, but they also suggest that the appearance of ODC defects in the fiber is associated with the introduction of Yb and the process by which the fiber is formed.
A drug-controllable tag for visualizing newly synthesized proteins in cells and whole animals

Research on basic cellular processes involving local production or delivery of proteins, such as activity-dependent synaptic modification in neurons, would benefit greatly from a robust, nontoxic method to visualize selectively newly synthesized copies of proteins of interest within cells, tissues, or animals. We report a technique for covalent labeling of newly synthesized proteins of interest based on drug-dependent preservation of epitope tags. Epitope tags are removed from proteins of interest immediately after translation by the activity of a sequence-specific protease until the time a protease inhibitor is added, after which newly synthesized protein copies retain their tags. This method, which we call TimeSTAMP for time-specific tagging for the age measurement of proteins, allows sensitive and nonperturbative visualization and quantification of newly synthesized proteins of interest with exceptionally tight temporal control. We demonstrate applications of TimeSTAMP in retrospectively identifying growing synapses in cultured neurons and in visualizing the distribution of recently synthesized proteins in intact fly brains.
Attitude compensated electronic compass for aircraft navigation

A magnetic compass has been developed by the Research Laboratory for Avionics System of the University of Florida intended to replace the common mechanical directional gyroscope for aircraft heading indication. The compass is based on an assembly of three mutually orthogonal single-core magnetic sensors, affixed to the fuselage, thus remaining in the aircraft frame of reference. The sensor electronics incorporate a feedback circuit that applies direct current to the sensor, sufficient to cancel the magnetic flux bias of the Earth field. This scheme results in a very accurate three dimensional measurement of the Earth's magnetic field vector, which is related to the attitude (roll, pitch and heading) of the aircraft through a set of algebraic equations. If the pitch angle is known, from an artificial horizon for instance, these equations can be served using a microprocessor in order to obtain the heading and the roll of the aircraft.
PGJ2 Provides Prolonged CNS Stroke Protection by Reducing White Matter Edema

Few clinically effective approaches reduce CNS-white matter injury. After early in-vivo white matter infarct, NFκB-driven pro-inflammatory signals can amplify a relatively small amount of vascular damage, resulting in progressive endothelial dysfunction to create a severe ischemic lesion. This process can be minimized by 15-deoxy-Δ12,14-prostaglandin J2 (PGJ2), an analog of the metabolically active PGD2 metabolite. We evaluated PGJ2's effects and mechanisms using rodent anterior ischemic optic neuropathy (rAION); an in vivo white matter ischemia model. PGJ2 administration systemically administered either acutely or 5 hours post-insult results in significant neuroprotection, with stereologic evaluation showing improved neuronal survival 30 days post-infarct. Quantitative capillary vascular analysis reveals that PGJ2 improves perfusion at 1 day post-infarct by reducing tissue edema. Our results suggest that PGJ2 acts by reducing NFκB signaling through preventing p65 nuclear localization and inhibiting inflammatory gene expression. Importantly, PGJ2 showed no in vivo toxicity structurally as measured by optic nerve (ON) myelin thickness, functionally by ON-compound action potentials, on a cellular basis by oligodendrocyte precursor survival or changes in ON-myelin gene expression. PGJ2 may be a clinically useful neuroprotective agent for ON and other CNS infarcts involving white matter, with mechanisms of action enabling effective treatment beyond the currently considered maximal time for intervention.
Cerebral Lobes in Autism: Early Hyperplasia and Abnormal Age Effects

Metabolic, functional, behavioral, and histologic studies suggest that the structure of the cerebrum may be abnormal in autism. In a previous cross-sectional study we found abnormal enlargement of cerebral cortex and cerebral white matter volumes in autistic 2- and 3-year-olds and abnormally slow rates of volume change across later ages. In the present study, we assessed whether these volume abnormalities are limited to particular cerebral regions or are pervasive throughout the cerebrum. We used magnetic resonance imaging (MRI) to quantify volumes of cerebral lobes (frontal, temporal, parietal, and occipital regions), using classic sulcal boundaries to define regions. We examined 38 boys with autism and 39 normal control boys between the ages of 2 and 11 years. Several regions showed signs of gray matter and white matter hyperplasia in 2- and 3-year-old patients (as much as 20% enlargement), but there appeared to be an anterior to posterior gradient in the degree of hyperplasia. The frontal lobe showed the greatest enlargement while the occipital lobe was not significantly different from normal. Gray and white matter differences were not found in the older children. By examining the relationships between regional volumes and subject age, we found that frontal, temporal, and parietal white matter volumes, as well as frontal and temporal gray matter volumes, changed at significantly slower rates in autism patients than in controls across the 2- to 11-year-age range. For example, frontal lobe white matter volume increased by about 45% from 2-4 years of age to 9-11.5 years, but by only 13% in autistic patients. Mechanisms that might account for early hyperplasia are discussed as they might relate to the regional differences in degree of abnormality. For instance, possible influences of neurotrophic factors, or of abnormal afferent activity from other affected brain regions are considered.
Mouse models for cardiomyopathy research

Abstract Cardiomyopathy refers to a family of inherited or acquired systemic diseases that primarily affect cardiac muscle. Cardiomyopathies can be divided into four main subtypes, based on morphological and physiological defects within the cardiac muscle itself, which include: (1) dilated cardiomyopathy, (2) hypertrophic cardiomyopathy, (3) restrictive cardiomyopathy and (4) arrhythmogenic right ventricular dysplasia/cardiomyopathy. Genetics have been shown to play an increasingly important role in the onset of cardiomyopathies. As a result, the mouse has emerged as the most used animal model for cardiomyopathy research, largely based on the availabilities of genetic technologies to manipulate the mouse genome. Mouse models have given the cardiovascular field significant insights into the molecular mechanisms and genetic factors underlying the etiology and pathogenesis of various cardiomyopathies. This review will first, discuss genetic approaches to generate mouse models as well as highlight certain mouse models which have exploited gene knockout and transgenic expression of mutant proteins associated with human cardiomyopathies, to study mechanisms involved in the pathogenesis of these various subtypes of cardiomyopathies.
Solubilities of fatty acids, fatty acid esters, triglycerides, and fats and oils in supercritical carbon dioxide

Using supercritical carbon dioxide (SC-CO2) as the solvent, the solubility of methyl esters, ethyl esters, fatty acids, triglycerides, and fats and oils were studied over a range of temperature and pressures. Equilibrium data from the literature were correlated using the Peng-Robinson equation of state. With the van der Waals (VDW) and Panagiotopoulos and Reid (PR) mixing rules. The data were also correlated using statistical methods and the solubilities predicted by various models were compared with experimental solubilities at the temperature and pressure conditions studied. The equation of state method provided good agreement of theory with experiment for the solubilities of fatty acids and their esters, but less so for the triglycerides, fats and oils. The statistical methods on the other hand, not only predicted the solubilities of fatty acids and fatty acid esters well, but also gave good agreement with the solubilities of triglycerides, fats and oils. Chain length, degree of unsaturation, and functional groups in compounds are known to affect the vapor pressures of these compounds which in turn influence their solubilities in SCCO2. As expected solubilities decreased in going from fatty acid esters, to fatty acids, to triglycerides.
Performance Oriented Programming for NUMA Architectures

OpenMP is emerging as a viable high-level programming model for shared memory parallel systems. Although it has also been implemented on ccNUMA architectures, it is hard to obtain high performance on such systems, particularly when large numbers of threads are involved. Moreover, it is applicable to NUMA machines only if a software DSM system is present. In this paper, we discuss various ways in which OpenMP may be used on ccNUMA and NUMA architectures, and evaluate several programming styles on the SGI Origin 2000, and on TreadMarks, a Software Distributed Shared Memory System from Rice University. These results have encouraged us to begin work on a compiler that accepts an extended OpenMP and translates such code to an equivalent version that provides superior performance on both of these platforms.
Policy-Induced Constraints in the Design and Commercialization of Monitoring Devices: An Assessment of Three Technologies’ Reimbursement Models

Successful commercialization of medical technologies increasingly requires developers and manufacturers to think early-on about regulatory approval and reimbursement strategies for their new devices. This can be particularly challenging in the case of monitoring devices, where demonstrating the effectiveness and finding the coding and coverage can often be a complicated and lengthy process, particularly with the given current reimbursement policy. In this paper, we use three technology case studies to examine how firms are navigating the status quo and illustrate the importance of incorporating a comprehensive understanding of current market and regulatory constraints into the development and commercialization process. The case studies suggest that viable approaches can include pairing a monitoring technology with a therapy, or relying on hospital-pay or patient-pay models that are based on demonstration of direct benefits or cost-savings to these parties. The results emphasize that successful innovation in monitoring technologies increasingly requires a very closely aligned engineering, business, and health-economic strategy. Developing a comprehensive understanding of the specific value drivers and policy-induced constraints can contribute substantially to achieving the true benefits of monitoring technologies.
Design, folding, and activities of metal-assembled coiled coil proteins.

Metal ions serve many purposes in natural proteins, from the stabilization of tertiary structure to the direction of protein folding to crucial roles in electron transfer and catalysis. There is co...
Pediatric intestinal transplantation: the resected allograft.

We reviewed the clinical and pathologic finding of 22 resected allografts from 19 of the 83 children who underwent a variety of small intestinal transplant procedures in the years 1990–2000 at the Children’s Hospital of Pittsburgh. Resections were compared with prior mucosal biopsies because resections allow for evaluation of the entire bowel thickness, including the feeding vessels, and obviate the problems of limited sampling. Partial resections that were done soon after the transplant, or soon after additional surgery, were for surgical problems such as leaks, adhesions, and volvulus. None had biopsy features suggestive of rejection or infection. Partial resections done late (6 months or more) after transplantation were more likely to be related to allograft immune biology; two had a sclerosing peritonitis that was confined to the allograft, and one had an obstructing carcinoma arising in the allograft mucosa. One patient had a localized stricture, demonstrated to be due to graft vascular disease at partial resection, and this patient went on to have the allograft removed a year later for chronic rejection. Early complete allograft enterectomies were for refractory acute cellular rejection, 1–2 months following transplant. One was removed for pancreatitis and liver failure from operative complications. Late allograft enterectomies were generally for chronic rejection, some with residual acute rejection, but there were also a number of patients who had multiple superimposed conditions such as cytomegalovirus, Epstein-Barr virus, and post-transplant lymphoproliferative disorder in various combinations. One had idiopathic scarring and developed an adynamic bowel that remains unexplained. Examination of the resected specimens allows for dissection of the multiple contributions to graft failure, especially the vascular disease that can rarely be seen on mucosal biopsy. An unexpected finding was the impressive hypertrophy of neural elements, nerves, and ganglion cells in many of the patients, the significance of which requires further investigation.
Veda-scope: More comfortable than the bivalve speculum and cytologically equivalent.

Objective: The aim of the present study was to confirm that the Veda-scope is equivalent to the bivalve speculum in the collection of endocervical cells, as confirmation of adequate cervical sampling for Pap smear testing. The study also aimed to assess the comfort level of the Veda-scope compared to the traditional bivalve speculum and the patient preference of the Veda-scope compared to the bivalve speculum. Methodology: Multicentre, randomised, controlled crossover, cytologist blinded study. Population: The total number of subjects enrolled in the study were 250. The number of evaluable subjects were 210. Results: In primary efficacy analysis, no significant difference was seen between the presence or absence of endocervical cells in the smears using either the Veda-scope or the bivalve speculum. There was a high concordance level between the diagnosis assigned to each specimen of a paired sample, the diagnosis agreeing in 97.6% cases. The primary reason given by many women for avoidance of regular Pap smear examinations is the discomfort or pain experienced with sample collection with the bivalve speculum. In the present study, 92% of subjects indicated a preference for the Veda-scope for Pap smear collection, while only 8.4% preferred the bivalve speculum. Subject preference was also assessed with respect to how the subject rated the comfort level of her previous Pap smear. In subjects who rated their previous Pap smear as very comfortable or comfortable, 86% expressed a preference for the Veda-scope. This rose to 93% in subjects who rated their previous Pap smear as only tolerable. Conclusion: The results of the present study show that Pap smear collections with the Veda-scope are of equal quality to those collected with the bivalve speculum, with an equivalent diagnostic outcome. A very strong preference for the Veda-scope was shown by the women enrolled in the present study based on the comfort levels experienced with the two devices.
Performance study of buffer management schemes under multicasting traffic in ATM switching nodes

Multimedia applications in broadband ISDN present various types and classes of traffics such as video teleconferencing, broadband telephony and large file transfers. Multicasting is important in multimedia applications. Since cell loss in a multicast packet will cause the retransmission of the entire packet causing excessive load in the network, the ATM switch should provide for the reduction of cell loss of multicast traffic. The reduction in cell loss of a particular type of traffic should be done in coordination with the QoS parameters required from other classes within each traffic type. Buffering schemes are used in ATM switches to achieve the required levels of QoS. In this paper, we develop a new buffering scheme which considers traffic types that include multicasting and nonmulticasting components with two classes of cells within each traffic type. We compare the new buffering scheme with two existing schemes, No Priority and Push Out. We show that the new buffering scheme performs better than the two other schemes by reducing cell loss of multicast cells. We also introduce a new cell scheduling policy that produces lower delay for the delay sensitive class. The new buffering and scheduling schemes provide the ability to tune the cell loss and delay of each class of cells within each traffic type.
In situ studies of butyronitrile adsorption and hydrogenation on Pt/Al2O3 using attenuated total reflection infrared spectroscopy.

The adsorption and hydrogenation of butyronitrile (BN) in hexane on a 5% Pt/Al2O3 catalyst has been studied using in situ attenuated total reflection infrared (ATR-IR) spectroscopy. ATR-IR measurements were conducted on thin (∼10 μm) films of catalyst deposited on Ge wave guides. Multivariate analysis involving classical lease-squares (CLS) and partial least-squares (PLS) modeling was used to aid in the interpretation of the spectroscopic data. During the adsorption of BN over a concentration range from 4 to 40 mM in hexane, no clear evidence for adsorbed N-bound end-on species could be detected. However, a feature at ∼1635−1640 cm-1 indicated the presence of an adsorbed imine species, with the CN group existing in a tilted configuration involving a strong degree of π interaction with the surface. This assignment is bolstered by the detection of N−H stretching bands that are consistent with imine vibrations. This imine-type intermediate is very prominent and shows transient behavior in the presence of sol...
A Switching Scheme for Multilevel Converters with Non-Equal DC Sources

In this paper, we consider unequal voltage sources of integer multiple magnitudes, in cascaded H-bridge converters. The converter uses (m-1)/2 voltage sources and the proposed switching scheme render an m -level staircase waveform with equal steps. Since the resulting voltage levels are equal, the angles are determined for the complete elimination of (m-1) unwanted harmonics. The implementation of switching scheme, in single and three-phase configurations were simulated with Ansoft -Simplorerreg and the frequency spectrum of the resulting waveform and its THD are shown to verify the results. Source and switch utilization were also evaluated.
Shape estimation for arbitrary objects

Shape recognition for arbitrarily shaped objects is a very difficult problem in machine vision and in remote sensing. The radiometric technique described can be used for arbitrary illumination and detection coordinates to obtain surface shape. Using a high resolution CCD-based imager, the local surface curvature is shown to produce significant changes in the detected signal-to-noise ratio, sufficient to reconstruct the object piece-wise continuous shape from the object slope as a function of the projected pixel position. The technique is applied to remote sensing for digital map generation and obstacle shape determination to avoid hazards for autonomous vehicles.
Smart structures: Part I—Active and semi-active control

Abstract This paper and a companion paper present a state-of-the-art review of significant research performed in the area of smart structures. The focus of the review is journal articles published since 1997. This paper reviews articles on active and-semi active control of structures using a variety of systems. Active control systems include active tuned mass dampers, distributed actuators, active tendon systems and active coupled building systems. Semi-active control systems include: magnetorheological (MR) fluid dampers, semi-active stiffness dampers, semi-active tuned liquid column dampers, and piezoelectric dampers. A review of hybrid control systems and control strategies is presented in the companion paper.
Confluence of natural hazards: A possible scenario

As society considers hazards that may affect human populations on a large scale, it is best to avoid the Chicken Little syndrome. Overreaction will serve no useful purpose. On the other hand, we should also recognize the increasing vulnerability that our society faces as it builds up dependencies on highly complex, and highly interconnected, technologies.
Voltage-activated potassium currents in acutely dissociated hippocampal dentate gyrus neurons from neonatal rats

Abstract We have studied outward currents of neurons acutely dissociated from the dentate gyrus region of hippocampus using whole-cell and perforated patch recordings. Depolarizing voltage commands activated sustained outward currents at all ages tested (P5–P30). Outward currents were blocked by tetrathylammonium (10 mM) but not 4-aminopyridine (25 mM). Comparison of sustained potassium current during postnatal development showed a significant increase in current amplitude with age reaching a peak between P20 and P30. These results suggest an overall increase in the number of voltage-dependent ionic channels during development, specifically those underlying TEA-sensitive potassium currents.
Fuel-Mercury Combustion Emissions: An Important Heterogeneous Mechanism and an Overall Review of its Implications

An extensive examination of combustion gases containing trace amounts of mercury shows unambiguously mercury’s propensity for heterogeneous chemistry. Although additional mechanisms for the oxidation chemistry of mercury have been implied by the continuing inadequacy of modeling attempts, details of the specific chemistry have remained unknown. Now it is shown that mercury can efficiently chemi-deposit onto surfaces encountered in practical combustors. If sulfur is present, condensed mercuric sulfate forms momentarily. This is then converted by gaseous HCl to HgCl2 that may sublime into the flow or be retained. This elusive and efficient noncatalytic mechanism most likely explains the observed fractional conversions to the dichloride observed in coal combustors. A receptive surface acts solely as an intermediary, facilitating the conversion while disguising its role. Without sulfur, a corresponding mechanism occurs but via HgO that is similarly converted to the dihalide. Such heterogeneous dynamics have s...
Spectrochemical Analysis as a Tool in Geochemistry

"The tasks of geochemistry are firstly, to determine the composition of the earth, and secondly, to find the laws of distribution of the elements." This statement by the late V. M. Goldschmidt may be taken to convey what is usually meant by geochemistry. It need hardly be emphasized which of the two main aspects of geochemistry will be discussed here.
What is chronic pain

Chronic pain leads to individual suffering and to major costs for all developed countries. Previous studies suggest that both the incidence of disabling chronic pain and the amount of health care consumption due to chronic pain are rapidly increasing. Western medicine is not only often ineffective but may be one of the causes of this epidemic. This article will address the issue of chronic pain of unknown etiology and has the goals of: (1) identifying the factors which have led to our confusion about this topic, and (2) proposing alternative ways of conceptualizing chronic pain and its ensuing behaviors and social consequences. It is concluded that it is essential to discriminate between tissue damage, pain, suffering, pain behaviors, health care consumption, impairment and disability if one is to develop a meaningful conceptualization of the medical, social, economic and political problems of chronic pain. Successful treatment must be defined in behavioral terms such as restoration of normal activities. Disabling chronic pain is often a sign of overwhelming stress engendered by the individual's failure to cope with the demands of industrialized society.
Quantification of the major apolipoproteins in chicken and turkey serum during embryonic development

Abstract 1. 1. Apoproteins A-I and B (Apo A-I and Apo B) in whole sera of turkey and chicken embryos, and adults, were measured by electroimmunoassay. 2. 2. In embryos of both species concentrations of apoprotein A-I, characteristic of high density lipoproteins, are low during early development and increase sharply just before hatching. 3. 3. In embryos of both species concentrations of apoprotein B, charactersitic of very low and low density lipoproteins are relatively high during early development and decrease during the latter third of the incubation period. 4. 4. Until the attainment of young adulthood apoprotein A-I is lower in the turkey and apoprotein B is higher in turkey sera as compared to concentrations of these moieties in sera of chicken embryos and juveniles. 5. 5. On the day preceding hatching, there is a marked increase in liver RNA from turkey embryos but not in chicken embryos.
IgG Antineutrophil Cytoplasmic Antibodies in IgA Nephropathy: A Clinical Variant?

Anti-neutrophil cytoplasmic antibodies (ANCAs) of the immunoglobulin (Ig) G isotype are associated with rapidly progressive glomerulonephritis. These have been detected rarely in patients with Henoch-Schonlein purpura (HSP) and have only been previously reported once in a patient with IgA nephropathy (IgAN). In contrast, IgA-ANCAs have been detected in patients with HSP or IgAN, although further verification of this finding by various investigators has yielded conflicting results. We report a case of biopsy-proven IgAN in which the patient developed a rapidly progressive glomerulonephritis and was determined to have ANCAs of both IgA and IgG isotypes. This report suggests an association between fulminant IgAN and ANCA-associated disease and that ANCAs may be underdetected in children with previously diagnosed IgAN. Identification of these antibodies may guide further management of these patients.
Requiem for Battleship Yamato

Yoshida Mitsuru''s first-hand account of the Second World War battle leading to the destruction of Japan''s battleship Yamato is a classic of war literature'
Considerations for the School Psychologist when Providing Services for Maltreated Foster Children: A Developmental Perspective

As the body of research on attachment grows, attachment theory is being increasingly utilized by psychologists as a useful way of conceptualizing the problem behaviors that many foster children present. In addition, this paper explores Bowlby’s (1988) model of developmental pathways as a means to understand both normal and abnormal processes and patterns of adaptation and maladaptation. The empirical bases connecting the theoretical principles of attachment with child maltreatment are discussed, and a theoretical rationale for assessment and intervention with attachment-disordered foster children with an emphasis on modifying the child’s negative working model of attachment relationships is presented.