cssi/SciSciGPT-SciSciNet huggingface dataset:
CITIZEN PARTICIPATION IN NATURAL RESOURCE MANAGEMENT: DOES REPRESENTATIVENESS MATTER?

ABSTRACT The main focus of this research is on the changing role of citizen participation in natural resource management. Evidence suggests that citizens who participate in the management of natural resources are not representative of stakeholders who are impacted by the decisions being made. In an effort to assess the representativeness of citizen participation, we conducted telephone surveys of “residents” who live in the watershed of Tennessee Valley Authority's (TVA) Norris Reservoir and “participants” in TVA's Norris Public Lands Plan. As hypothesized, we found participants to be older, disproportionately male, more educated, and more affluent, and as having higher levels of political efficacy and trust in government than residents. Exploratory analyses revealed many other significant differences between participants and residents. We conclude by suggesting that increased and representative citizen participation is necessary for the successful implementation of an ecosystem-based approach and to addr...
Exceptional H2 saturation uptake in microporous metal-organic frameworks.

Saturation H2 uptake in a series of microporous metal−organic frameworks (MOFs) has been measured at 77 K. Saturation pressures vary between 25 and 80 bar across the series, with MOF-177 showing the highest uptake on a gravimetric basis (7.5 wt %) and IRMOF-20 showing the highest uptake on a volumetric basis at 34 g/L. These results demonstrate that maximum H2 storage capacity in MOFs correlates well to surface area, and that feasible volumetric uptakes can be realized even in highly porous materials.
AN EVALUATION OF REBREATH1NG IN A MODIFIED T-PIECE SYSTEM DURING CONTROLLED VENTILATION OF ANAESTHETIZED CHILDREN

Measurements of minute volumc, airway pressure, and inspired and end-expired carbon dioxide concentrations were made on anaesthetized children during the use of controlled ventilation with a modified T-piece system. The data obtained indicate that a fresh gas inflow as low as 100 ml/lb. (220 ml/kg) body weight per minute, with a minimum total flow of 3 1./min, is sufficient to prevent carbon dioxide retention. The influence of the rate of ventilation upon end-expired carbon dioxide concentration also was assessed.
Structural and Phylogenetic Analysis of Adenovirus Hexons by Use of High-Resolution X-Ray Crystallographic, Molecular Modeling, and Sequence-Based Methods

A major impediment to the use of adenovirus as a gene therapy vector and for vaccine applications is the host immune response to adenovirus hexon-the major protein component of the icosahedral capsid. A solution may lie in novel vectors with modified or chimeric hexons designed to evade the immune response. To facilitate this approach, we have distinguished the portion of hexon that all serotypes have in common from the hypervariable regions that are responsible for capsid diversity and type-specific immunogenicity. The common hexon core-conserved because it forms the viral capsid-sets boundaries to the regions where modifications can be made to produce nonnative hexons. The core has been defined from the large and diverse set of known hexon sequences by an accurate alignment based on the newly refined crystal structures of human adenovirus types 2 (Ad2) and Ad5 hexon. Comparison of the two hexon models, which are the most accurate so far, reveals that over 90% of the residues in each have three-dimensional positions that closely match. Structures for more distant hexons were predicted by building molecular models of human Ad4, chimpanzee adenovirus (AdC68), and fowl adenovirus 1 (FAV1 or CELO). The five structures were then used to guide the alignment of the 40 full-length (>900 residues) hexon sequences in public databases. Distance- and parsimony-based phylogenetic trees are consistent and reveal evolutionary relationships between adenovirus types that parallel those of their animal hosts. The combination of crystallography, molecular modeling, and phylogenetic analysis defines a conserved molecular core that can serve as the armature for the directed design of novel hexons.
Evolution of lactate dehydrogenase-A homologs of barracuda fishes (genus Sphyraena) from different thermal environments: differences in kinetic properties and thermal stability are due to amino acid substitutions outside the active site.

Orthologous homologs of lactate dehydrogenase-A (LDH-A) (EC 1.1.1.27; NAD+:lactate oxidoreductase) of six barracuda species (genus Sphyraena) display differences in Michaelis−Menten constants (apparent Km) for substrate (pyruvate) and cofactor (NADH) that reflect evolution at different habitat temperatures. Significant increases in Km with increasing measurement temperature occur for all homologs, yet Km at normal body temperatures is similar among species because of the inverse relationship between adaptation temperature and Km. Thermal stabilities of the homologs also differ. To determine the amino acid substitutions responsible for differences in Km and thermal stability, peptide mapping of the LDH-As of all six species was first performed. Then, the amino acid sequences of the three homologs having the most similar peptide maps, those of the north temperate species, S. argentea, the subtropical species, S. lucasana, and the south temperate species, S. idiastes, were deduced from the respective cDNA se...
Necessity of field dependence for interacting currents

Abstract It is shown that the vanishing of the equal time commutators of axial, vector or tensor currents (conserved or not) with the canonical fields to which they couple implies the vanishing of the interaction.
Successful directional atherectomy of eccentric renal artery stenosis using the simpson directional coronary atherocath as a primary therapy

A 67-yr-old female patient with accelerated hypertension, severe peripheral vascular disease, diabetes mellitus, and coronary artery disease had an abnormal renal scan, renal angiogram, and renal vein renin determination with lateralization to the left kidney. Angiography demonstrated a very tight, eccentric plaque obstructing the left renal artery of approximately 99%. Because of the anatomy of the plaque, balloon dilatation was deemed inadvisable. Subsequently, a Simpson 7F graft DCA atherocath through a four-curved 10F right bypass graft guiding catheter was used to successfully debulk the left renal artery. After debulking, the artery was dilated with a 5 mm Meditech balloon on a wire through a Cobra guiding catheter. The patient's blood pressure responded immediately and there were no complications. A large amount of atherosclerotic plaque was removed from the renal artery.
Quantitative Study Of Deconvolution And Display Mappings For Long-Tailed Point-Spread Functions

An important goal in medical imaging is to increase the accuracy of visual detection of small abnormal regions. The presence of scatter in the image degrades spatial resolution by introducing long tails to the point-spread function. We show in this paper that linear deconvolution can be used to improve the performance of the human observer in the two-hypothesis detection task. Also, we investigate the effect that linear grey-scale mappings have on the human observer performance. We demonstrate that they help the human observer in the detection task and can be used sequentially with deconvolution to yield a better performance.
Trajectory simulation of kinetic equations for classical systems

We formulate a linear theory of physical kinetics describing the relaxation of atoms from a non-equilibrium distribution. The evolution of the single-particle distribution function is decomposed into trajectories, each corresponding to a different realization of a sequence of collisions. Accumulating all possible trajectories gives the dynamics described by the classical Boltzmann equation. The significance of our method is that the required computation time scales linearly with the number of points used to sample the distribution function. This leads to the interesting possibility of extending our method to consider quantum coherences and the growth of long-range order in Bose - Einstein condensation where a large set of basis states may be required.
Giant cervical polyp

A giant cervical polyp occurring in a 56-year-old multiparous woman is described. Although the polyp was benign, total hysterectomy and bilateral salpingo-oophorectomy were carried out because of incidental cystic and adenomatous hyperplasia of the endometrium.
Intrathoracic Skeletal Muscle Ventricles: A Feasibility Study

For skeletal muscle ventricles (SMVs) to be applied clinically, it is likely that they will have to be placed within the chest. Ease of subsequent connection to the circulation, and avoidance of significant lung compression, are factors that could influence SMV size and shape in a way that may prejudice their ability to pump effectively at physiological preloads. In five dogs, specially designed SMVs were constructed from the latissimus dorsi muscle, and placed in the apex of the left hemithorax. After a 3-week delay, the muscle was preconditioned electrically by 2-Hz continuous stimulation for 6 weeks. At a later thoracotomy, this positioning of SMVs permitted easy surgical access to the heart and great vessels. SMVs were then connected to a mock circulation device for functional evaluation. As right-sided pumps, at a preload of 10 mmHg, SMVs generated a stroke volume (SV) and stroke work (SW) exceeding that of the native right ventricle (SV = 8.9 +/- 0.8 vs 7.9 +/- 0.6 mL; SW = 0.44 +/- 0.03 vs 0.20 ergs x 10(6)). As left-sided pumps, also at a preload of 10 mmHg, SMV SV, and SW was roughly half that of the left ventricle (SV = 3.7 +/- 0.2 vs 7.9 +/- 0.6 mL; SW = 0.29 +/- 0.03 vs 0.57 +/- 0.05 ergs x 10(6)). SMVs may conveniently be positioned inside the chest, where they have the potential to function as left or right heart assist devices.
New laser treatment approaches for benign prostatic hyperplasia.

The recent introduction of higher power 100 W holmium: yttrium-aluminum-garnet (Ho:YAG) and 80 W potassium titanyl phosphate lasers for rapid incision and vaporization of the prostate has resulted in renewed interest in the use of lasers for treatment of benign prostatic hyperplasia (BPH). Although long-term studies are still lacking, short-term results demonstrate that these procedures are at least as safe and effective in relieving BPH symptoms as transurethral resection of the prostate and may provide reduced morbidity. Other laser techniques, such as interstitial laser coagulation and contact laser vaporization of the prostate, have lost popularity due to complications with increased catheterization time, irritative symptoms, and infection rates. Although Ho:YAG laser enucleation of the prostate is more difficult to learn and a slower procedure than potassium titanyl phosphate laser vaporization, the Ho:YAG laser is currently the most proven laser technique for BPH treatment. This article reviews the latest developments in laser treatment of BPH over the past 2 years and provides a view toward the future of lasers in the treatment of BPH.
Extending the linear regime of the seismic waveform inversion problem

A method is presented for expanding the “locally linear” regime in the iterative seismic waveform inverse problem. This formulation increases the class of starting models that successfully converge on a solution.
Fungal causes of otitis externa and tympanostomy tube otorrhea

Summary Objective: To describe the occurrence of fungal organisms in the setting of otitis externa and tympanostomy tube otorrhea, review the treatment course, timing of diagnosis, organism identified and time to resolution with fungal infections. Design: Retrospective review. Setting: Pediatric otolaryngology clinic within a tertiary care hospital. Patients: One hundred and sixty-six patients (ages 16 days to 18 years) with fungal organisms on ear culture. Outcome measures: Number of prior therapies, number of office visits, time to resolution and anti-fungal therapy. Results: Ear cultures positive for fungal organisms were found in 166 patients seen between 1 January 1996 and 30 September 2003 from a total of 1242 patients undergoing ear culture. Comparing the 3-year period (1996–1998) prior to the availability of fluoroquinolone ototopical drops to the 3-year period after (1999–2001), there is a statistically significant increase in the incidence of positive fungal culture (p Conclusions: Otorrhea due to fungal organisms occurs in the setting of refractory infection and is often discovered after multiple oral and ototopical antibacterial medications. Due to the extended treatment period required to clear fungal organism, timely diagnosis with culture for bacteria and fungus is required in patients with persistent otorrhea. An increase in incidence of fungal infections of the ear was found in the period after widespread use of ofloxacin began.
Feasibility of recruitment for an efficacy trial of emergency contraceptive pills

Abstract Background The efficacy of emergency contraceptive pills (ECPs) is currently uncertain. The best way to obtain a robust efficacy estimate would be to conduct a placebo-controlled randomized trial. We aimed to assess the feasibility of identifying women eligible for such a trial. Study Design We conducted a survey of women aged 18–35 years in five sexually transmitted disease clinics and urgent care centers in Kenya and the United States in 2006. Results Of 177 women surveyed, only 10 (6%) reported no reasons for exclusion from a potential efficacy trial. Of the rest, 149 (83%) had not recently had sex that conferred a substantial risk of pregnancy. At all sites combined, the rate of identification of potentially eligible women was 0.6 per day of interviewing. Conclusion A placebo-controlled efficacy trial of ECPs would likely require several thousand participants. Recruitment for such a trial in these types of sites would be prolonged.
Comparison of Subsidence Failure Between a Cervical Cage and a Cortical Allograft in a Human Cadaveric Model

Interbody fusion (IBF) is an accepted procedure for the treatment of single-level cervical disc disease. The goal of interbody fusion in the cervical spine is to restore disc height and achieve solid arthrodesis; however, a concern with IBF devices is subsidence. The purpose of this study was to biomechanically test and compare subsidence between two cervical interbody fusion techniques, under axial compressive loading in a human cadaveric cervical model.Copyright © 2002 by ASME
Systematic variation in effects of serotonin and norepinephrine on repetitive firing properties of ventral horn neurons

Spinal interneurons are essential integrators of descending and peripheral input that receive profuse monoaminergic influence from brainstem nuclei. In this study, the effects of the monoamines serotonin and norepinephrine on the intrinsic properties of ventral horn interneurons were investigated in a slice preparation of the lumbar cord of 7-19 day old rats. Three cell groups with distinct firing patterns in response to steps of injected current were observed and classified as repetitive-firing, initial-burst or single-spiking. Input conductance tended to be largest in single-spiking cells whereas repetitive-firing cells showed the greatest tendency for spontaneous firing and had the fastest rate of rise for the action potential. Rhythmic firing behaviors were defined by the frequency-current relation evoked by linearly increasing current ramps. The monoaminergic modulation of firing patterns and frequency-current relations was primarily studied in repetitive-firing cells. The frequency-current threshold current was decreased in cells with high pre-drug values and increased in cells with low pre-drug values. Therefore, monoamine administration decreased the input-output heterogeneity of the repetitive-firing cells by compressing the range of frequency-current threshold currents. This action of monoamines may have a key role in the suppression of sensory-evoked reflexes and the production of coordinated movement.
An update on stature estimation in prehistoric native Americans of Ohio

We present regression equations to estimate skeletal height and stature for prehistoric Native Americans of Ohio. The regression equations are based on skeletal height as the dependent variable and various postcranial elements and combinations of elements as the independent variables. A total of 171 individuals, 95 males and 76 females, make up the sample. The present sample includes the 64 individuals we previously used for stature estimation (Sciulli et al.: Am. J. Phys. Anthropol. 83:275–280, 1990) and 107 additional individuals distributed more widely in time and space. The present more inclusive sample, however, shows the same proportional contributions to skeletal height of each skeletal height component as the previous sample. This result suggests that these proportions were a consistent feature of the prehistoric Native Americans of Ohio. Because the prehistoric Native Americans of Ohio were characterized by relatively long legs and distal elements of the limbs, stature estimation from regressions based on East Asian populations, which express in general relatively short legs and distal limb elements, will overestimate stature in Native Americans of Ohio and, possibly, all Eastern Woodlands Native Americans. © 1993 Wiley-Liss, Inc.
Adaptive plasticity of head movement propensity.

Individual humans exhibit differing propensity to move the head in association with saccadic shifts in gaze. We assessed whether this tendency can be modified in normal subjects by either reducing neck mobility with a cervical collar or restricting the field of view using aperture spectacles. We quantified head movement propensity in terms of the range of orbital eccentricity within which the eyes are customarily maintained (customary ocular motor range), and the range of final eye-in-head eccentricity for which a planned saccade is likely to be executed without a concomitant head movement (eye-only range). Three subjects wore rigid collars during waking hours for periods of up to 9 days. We measured customary and eye-only ranges with the collar removed, at various times during the adaptation and recovery periods. Collar adaptation reduced head movement propensity in all three subjects, increasing the average customary ocular range from 27.6±8.9° (mean ± SD) to 66.1±4.5° and the eye-only range from 24.6±17.0° to 67.6±7.4°. In two subjects the modifications persisted for weeks following final collar removal. In parallel with the reduction in head movement propensity, all subjects improved in their ability to maintain eccentric gaze, suggesting that neck restriction led to effects at the level of the brainstem. Three subjects were adapted to spectacles, masked to restrict the field of view to approximately 20°. The aperture spectacles were worn for periods of up to 9 days. When tested without the apertures, one subject exhibited a definite increase in head movement propensity; in the other two, the data were equivocal, indicating either a small increase in head movement propensity or no effect. Averaged across subjects, customary ocular motor range decreased from 35.1±12.8° to 25.4±13.4° and eye-only range decreased from 35.1±7.5° to 23.0±4.0°. The marked difference in the magnitudes of collar- and spectacle-induced changes suggests that the responses to the two restrictive appliances are mediated by different mechanisms. Collar adaptation may involve parametric modulation of circuits mediating reflex recruitment of head movements, while aperture adaptation may primarily reflect substitution of an alternative mode of head control triggered by the presence of the restricted field of view, with only minor parametric modulation of the underlying head recruitment circuit. The enduring effects of restricting neck mobility upon head movement tendencies may relate to the common clinical association between neck injury and persistent dysequilibrium.
High‐volume aspiration as a supplemental scavenging method for reducing ambient nitrous oxide levels in the operatory: a laboratory study

Summary. Occupational exposure to low levels of nitrous oxide N2O have been associated with adverse health effects. The National Institute for Occupational Safety and Health has established a threshold guideline of 25 ppm N2O. The purpose of this laboratory study was to determine the effectiveness of a high-volume dental aspirator as a supplemental device to reduce ambient N2O levels in the operatory. The investigation evaluated four experimental groups that were assigned based on whether or not the aspirator was used and on the rate at which operatory ventilation was established (5 or 10 room air exchanges per hour). Ambient N2O levels were monitored at 30 cm from the nasal hood using an infrared spectrophotometer. The room air exchange rate was measured with a flow hood and then manipulated to the desired ventilation rate. N2O levels were detected with a spectrophotometer and data were recorded with a microprocessor that continuously collected data. The results demonstrated that both utilization of supplemental oral aspiration and increased operatory ventilation significantly reduced ambient N2O levels. It was concluded that a high-volume aspirator, when used in conjunction with the normal scavenging system, can significantly reduce ambient N2O levels to within the guidelines established by the National Institute for Occupational Safety and Health.
Partners in Science Education: An Undergraduate Experience

In this paper, we describe a unique partnership between a computer science course and a history/U.S. government course at the College of Staten Island. A cohort of students take the science and history courses together, and lectures, laboratory assignments, and reports in each subject reinforce the concepts learned in the other one. The intent of this partnership is to encourage general education students to think about science as an important component of their understanding of the world, and to impress upon them the relevance of science in their daily lives.
Topical antimicrobial protection of postoperative surgical sites at risk of infection with Propionibacterium acnes: an in-vitro study.

Summary Background Propionibacterium acnes is an increasingly recognized pathogen in surgical site infections, particularly in relation to joint replacements and spinal procedures. Due to its low virulence and slow-growing nature, clinical signs of infection may be prolonged, and diagnosis is often challenging. As a consequence, appropriate presurgical skin preparation and postsurgical protection of the wound using antimicrobial dressings are important considerations in the prevention of surgical site infections caused by P. acnes . Aim To investigate the antimicrobial efficacy of a silver-containing gelling fibre wound dressing against P. acnes using stringent in-vitro models that simulated a variety of wound conditions. Methods A simulated wound fluid model was used to quantify the killing capacity of the silver-containing dressing over time under conditions that mimicked a heavily exuding wound. A simulated colonized shallow wound model was used to investigate the impact of dressing conformability on antimicrobial activity, and a third model was designed to measure the efficacy of the dressing on bacteria embedded within a simulated colonized wound surface. Findings The in-vitro data demonstrated that the silver-containing wound dressing was bactericidal against P. acnes , it maintained its killing effect over a prolonged period (seven days) under conditions simulating excessive exudate, and the gelled dressing matrix (following hydration) enabled the dressing to conform to a simulated wound topography, thus optimizing antimicrobial activity in a shallow wound model. Conclusion Based on the in-vitro data generated, use of the silver-containing dressing as part of a postoperative care protocol may help to minimize the risk of prolonged and debilitating surgical site infections caused by P. acnes .
Injection and suction of an upper-convected maxwell fluid through a porous-walled tube

Abstract The steady-state, similarity solutions of the flow of an upper-convected Maxwell fluid through a tube with a porous wall are constructed by asymptotic and numerical analyses as functions of the direction of flow through the tube, the amount of elasticity in the fluid, as measured by the Deborah number De, and the degree of fluid slip along the tube wall. Fluid slip is assumed to be proportional to the local shear stress and is measured by a slip parameter β that ranges between no-slip (β = 1) and perfect slip (β = 0). The most interesting results are for fluid injection into the tube. For β = 1, the family of flows emanating from the Newtonian limit (De = 0) has a limit point where it turns back to lower values of De. These solutions become asymptotic to De = 0) and develop an O(De) boundary layer near the tube wall with singularly high stresses matched to homogeneous elongational flow in the core. This solution structure persists for all nonzero values of the slip parameter. For β ≠ 1, a family of exact solutions is found with extensional kinematics, but nonzero shear stress convected into the tube through the wall. These flows differ for low De from the Newtonian asymptote only by the absence of the boundary layer at the tube wall. Finite difference calculations evolve smoothly between the Newtonian-like and extensional solutions because of approximation error due to under-resolution of the boundary layer. The radial gradient of the axial normal stress of the extensional flow is infinite at the centerline of the tube for De > 1; this singularity causes failure of the finite difference approximations for these Deborah numbers unless the variables are rescaled to take the asymptotic behavior into account.
Decreased survival of mosquito cells after stable transfection with a Drosophila ecdysteroid response element: Possible involvement of a 40 kDa DNA binding protein

Homologous transfection systems provide a useful tool for characterizing promoters and other regulatory elements from cloned genes. We have used cultured Aedes albopictus C7–10 mosquito cells to evaluate expression of 20-hydroxyecdysone-inducible genes. Although this cell line has previously been shown to synthesize components of the ecdysteroid receptor and ecdysone-inducible proteins, the well-characterized ecdysteroid response element (EcRE) from the Drosophila hsp27 promoter failed to confer a substantial 20-hydroxyecdysone mediated induction in transfected mosquito cells. Recovery of stably transformed clones was also reduced in a DNA dependent manner when the EcREs were in the sense orientation, relative to control plasmids lacking the EcREs or containing an antisense construct. Finally, when tandem EcREs were placed within the hsp70 promoter, CAT activity was detected only after prolonged enzyme incubation, suggesting that the DNA interfered with cellular metabolism. In these constructs, we noted that the promoter DNA contained several potential binding sites for the activator protein-1 (AP-1) transcription factor, one of which lay between the tandem EcREs. On southwestern blots, a 40 kDa nuclear protein from C7–10 cells bound to DNA containing AP-1 sites. A DNA affinity column was used to partially purify the 40 kDa protein, and western analysis showed that the mosquito protein cross-reacted with a heterologous antibody to JUN. Likewise, mRNA from C7–10 cells cross-hybridized with the jun cDNA from Drosophila. These results suggest that like estrogen, 20-hydroxyecdysone interfaces with AP-1 as a co-activator protein that modulates the overall hormone response.
Aplastic anaemia treated by marrow transplantation.

Abstract 4 patients with complete marrow failure, 3 due to unknown cause and 1 associated with hepatitis, showed no indication of spontaneous recovery after 7 to 52 weeks of conventional and supportive treatment. They were conditioned for engraftment by the administration of cyclophosphamide, 50 mg. per kg., on each of 4 days, followed in 36 hours by marrow infusion. The marrow donor in each instance was a sibling of opposite sex who matched the recipient with regard to the major human histocompatibility locus (HL-A) as shown by cytotoxicity testing of the family and confirmed by non-reactivity in the mixed-leucocyte test. Methotrexate was given for a limited period after grafting as an immunosuppressive agent to modify the graft-versus-host disease. All 4 patients showed prompt engraftment indicated by a return of marrow cellularity and a rise of peripheral blood-counts, confirmed by cytogenetic analysis. 1 patient died of graft-versus-host disease with a cellular marrow 45 days after grafting. Another patient rejected his graft and died 67 days after grafting. 2 patients have excellent-functioning marrow grafts without graft-versus-host disease and are apparently well 138 and 215 days after grafting.
Aβ25–35 induces rapid lysis of red blood cells: contrast with Aβ1–42 and examination of underlying mechanisms

Abstract Amyloid β-peptide (Aβ) is produced by many different cell types and circulates in blood and cerebrospinal fluid in a soluble form. In Alzheimer's disease (AD), Aβ forms insoluble fibrillar aggregates that accumulate in association with cells of the brain parenchyma and vasculature. Both full-length Aβ (Aβ1–40/42) and the Aβ25–35 fragment can damage and kill neurons by a mechanism that may involve oxidative stress and disruption of calcium homeostasis. Circulating blood cells are exposed to soluble Aβ1–40/42 and may also be exposed to Aβ aggregates associated with the luminal surfaces of cerebral microvessels. We therefore examined the effects of Aβ25–35 and Aβ1–42 on human red blood cells (RBCs) and report that Aβ25–35, in contrast to Aβ1–42, induces rapid (10–60 min) lysis of RBCs. The mechanism of RBC lysis by Aβ25–35 involved ion channel formation and calcium influx, but did not involve oxidative stress because antioxidants did not prevent cell lysis. In contrast, Aβ1–42 induced a delayed (4–24 h) damage to RBCs which was attenuated by antioxidants. The damaging effects of both Aβ25–35 and Aβ1–42 towards RBCs were completely prevented by Congo red indicating a requirement for peptide fibril formation. Aβ1–42 induced membrane lipid peroxidation in RBC, and basal levels of lipid peroxidation in RBCs from AD patients were significantly greater than in age-matched controls, suggesting a possible role for Aβ1–42 in previously reported alterations in RBCs from AD patients.
Mechanism for the Peritectic Reaction and Growth of Aligned Grains in YBa2Cu3O6+x

It is experimentally observed that the peritectic reaction, 211 + liquid 123, can be driven essentially to completion in 1 h at an undercooling of only ∽30°C. The kinetic data, together with the observed microstructures, are inconsistent with the normal mechanism of the peritectic reaction. It is proposed that the mechanism of the reaction involves dissolution of 211 particles into the liquid and precipitation of solid 123. The aligned grain structure is explained through sympathetic nucleation of new 123 grains on existing grains.
Membrane receptor trafficking: evidence of proximal and distal zones conferred by two independent endoplasmic reticulum localization signals.

The generic membrane trafficking signals of internal RXR and carboxyl-terminal KKXX motifs direct intracellular endoplasmic reticulum (ER) localization of the signal-bearing proteins. These signaling motifs play a critical role in partitioning proteins into designated subcellular compartments by functioning as an intracellular “zip code.” In the process of determining the potential distinctions between these two otherwise functionally identical motifs, two functional zones of these signals were revealed. The KKXX signal was effective only when it was positioned closer to the membrane surface. In contrast, under identical conditions, the internal RXR signal was functional when it was positioned distally from the membrane. Different from the C-terminal KKXX signal, the internal RXR motif may be present in multiple copies. The receptor with multivalent RXR motifs displayed similar trafficking behavior to that of the same receptor with one copy of the RXR motif. The distinctive operating ranges from their anchored membrane surface provide experimental evidence for the notion that there are functional zoning layers within which membrane protein signal motifs are active.
Influence of plasticizers on poly(methyl methacrylate) ionomers

Abstract The influence of a polar plasticizer glycerol, and a nonpolar plasticizer, dioctylphthalate (DOP), on the microstructure and relaxation properties of poly(methyl methacrylate) ionomers has been investigated by dynamic mechanical thermal analysis. The test results indicate that glycerol strongly interacts with and weakens the ionic cluster ‘phase’, and also significantly increases the mobility of backbone hydrocarbon chains in the multiplet-containing matrix phase. In contrast, the nonpolar plasticizer DOP is more selective in that it appreciably reduces the glass transition temperature of the hydrocarbon-rich matrix phase, but has a much smaller effect than glycerol on the glass transition temperature of the ion-rich cluster ‘phase’. The present results are compared and contrasted with the effects of the same two plasticizers on polystyrene ionomers.
Noninvasive monitoring by photoplethysmography

The photoplethysmogram (PPG) is a noninvasive circulatory signal related to the pulsatile volume in tissue and is displayed by many pulse oximeters. The PPG is similar in appearance to the invasive arterial waveform, but is noninvasive and ubiquitous in hospitals. There is increasing interest in seeking circulatory information from the PPG and developing techniques for a wide variety of novel applications. This article addresses the basic physics of photoplethysmography, physiologic principles behind pulse oximetry operation, and recent technological advances in the usefulness of the PPG waveform to assess microcirculation and intravascular fluid volume monitoring during intensive care.
What Do Children Write in Science? A Study of the Genre Set in a Primary Science Classroom:

This article reports on the types of scientific writing found in two primary grade classrooms. These results are part of a larger two-year study whose purpose was to examine the development of info...
On the multiplexing effects of the ATM traffic

Traffic measurements taken from real data are highly desirable for validating traffic models, designing congestion control and flow control algorithms, implementing communication protocols, and developing switch architectures. This paper investigates the traffic characteristics of several applications in an ATM network with the goal of studying bursty traffic behavior and realizing the multiplexing effects of variable bit rate (VBR) traffic. Specifically, three types of traffic (ftp, voice, and video) are obtained from an ATM testbed. These applications are reported to be important applications that tend to dominate the wide-area networks. The multiplexing effects of FTP traffic are studied to identify empirical bandwidth requirements. The characteristics of the multiplexing effects can be applied to develop an efficient call admission algorithm based on the measured data. These experimental results designed to investigate traffic characteristics provide insights to bursty traffic behavior and performance requirements of practical real-time loads.
A model predicting delivery of saquinavir in nanoparticles to human monocyte/macrophage (Mo/Mac) cells.

Modeling the influence of a technology such as nanoparticle systems on drug delivery is beneficial in rational formulation design. While there are many studies showing drug delivery enhancement by nanoparticles, the literature provides little guidance regarding when nanoparticles are useful for delivery of a given drug. A model was developed predicting intracellular drug concentration in cultured cells dosed with nanoparticles. The model considered drug release from nanoparticles as well as drug and nanoparticle uptake by the cells as the key system processes. Mathematical expressions for these key processes were determined using experiments in which each process occurred in isolation. In these experiments, intracellular delivery of saquinavir, a low solubility drug dosed as a formulation of poly(ethylene oxide)-modified poly(epsilon- caprolactone) (PEO–PCL) nanoparticles, was studied in THP-1 human monocyte/macrophage (Mo/Mac) cells. The model accurately predicted the enhancement in intracellular concentration when drug was administered in nanoparticles compared to aqueous solution. This simple model highlights the importance of relative kinetics of nanoparticle uptake and drug release in determining overall enhancement of intracellular drug concentration when dosing with nanoparticles. Biotechnol. Bioeng. © 2008 Wiley Periodicals, Inc.
Production of the Cannibalism Toxin SDP Is a Multistep Process That Requires SdpA and SdpB

During the early stages of sporulation, a subpopulation of Bacillus subtilis cells secrete toxins that kill their genetically identical siblings in a process termed cannibalism. One of these toxins is encoded by the sdpC gene of the sdpABC operon. The active form of the SDP toxin is a 42-amino-acid peptide with a disulfide bond which is processed from an internal fragment of pro-SdpC. The factors required for the processing of pro-SdpC into mature SDP are not known. We provide evidence that pro-SdpC is secreted via the general secretory pathway and that signal peptide cleavage is a required step in the production of SDP. We also demonstrate that SdpAB are essential to produce mature SDP, which has toxin activity. Our data indicate that SdpAB are not required for secretion, translation, or stability of SdpC. Thus, SdpAB may participate in a posttranslation step in the production of SDP. The mature form of the SDP toxin contains a disulfide bond. Our data indicate that while the disulfide bond does increase activity of SDP, it is not essential for SDP activity. We demonstrate that the disulfide bond is formed independently of SdpAB. Taken together, our data suggest that SDP production is a multistep process and that SdpAB are required for SDP production likely by controlling, directly or indirectly, cleavage of SDP from the pro-SdpC precursor.
A parallel hash join algorithm for managing data skew

Presents a parallel hash join algorithm that is based on the concept of hierarchical hashing, to address the problem of data skew. The proposed algorithm splits the usual hash phase into a hash phase and an explicit transfer phase, and adds an extra scheduling phase between these two. During the scheduling phase, a heuristic optimization algorithm, using the output of the hash phase, attempts to balance the load across the multiple processors in the subsequent join phase. The algorithm naturally identifies the hash partitions with the largest skew values and splits them as necessary, assigning each of them to an optimal number of processors. Assuming for concreteness a Zipf-like distribution of the values in the join column, a join phase which is CPU-bound, and a shared nothing environment, the algorithm is shown to achieve good join phase load balancing, and to be robust relative to the degree of data skew and the total number of processors. The overall speedup due to this algorithm is compared to some existing parallel hash join methods. The proposed method does considerably better in high skew situations. >
Integrated design of navigation, guidance and control systems for unmanned underwater vehicles

The paper describes an integrated approach to the design of navigation, guidance and control systems for autonomous-unmanned-underwater vehicles (AUVs). The framework adopted is illustrated with a design example in which developments in H-infinity control theory, multi-rate navigation techniques and classical guidance strategies were applied to the design of a high level controller for the underwater vehicle MARIUS (Marine Utility Vehicle System). The problem statement requires the design of a command following system for the vehicle to achieve precise tracking of reference trajectories defined in an universal reference frame. This objective should be accomplished in the presence of shifting sea currents, sensor noise and vehicle parameter uncertainty. The design phase is described, and the interaction among navigation, control and guidance is analyzed. The performance of the complete command following system is evaluated using a simulation package that allows the designer to assess the impact of navigation, control and guidance algorithms on the dynamic performance of the vehicle. >
Type of stress ulcer prophylaxis and risk of nosocomial pneumonia in cardiac surgical patients: cohort study

Objective To examine the relation between the type of stress ulcer prophylaxis administered and the risk of postoperative pneumonia in patients undergoing coronary artery bypass grafting. Design Retrospective cohort study. Setting Premier Research Database. Participants: 21 214 patients undergoing coronary artery bypass graft surgery between 2004 and 2010; 9830 (46.3%) started proton pump inhibitors and 11 384 (53.7%) started H2 receptor antagonists in the immediate postoperative period. Main outcome measure Occurrence of postoperative pneumonia, assessed using appropriate diagnostic codes. Results Overall, 492 (5.0%) of the 9830 patients receiving a proton pump inhibitor and 487 (4.3%) of the 11 384 patients receiving an H2 receptor antagonist developed postoperative pneumonia during the index hospital admission. After propensity score adjustment, an elevated risk of pneumonia associated with treatment with proton pump inhibitors compared with H2 receptor antagonists remained (relative risk 1.19, 95% confidence interval 1.03 to 1.38). In the instrumental variable analysis, use of a proton pump inhibitor (compared with an H2 receptor antagonist) was associated with an increased risk of pneumonia of 8.2 (95% confidence interval 0.5 to 15.9) cases per 1000 patients. Conclusions Patients treated with proton pump inhibitors for stress ulcer had a small increase in the risk of postoperative pneumonia compared with patients treated with H2 receptor antagonists; this risk remained after confounding was accounted for using multiple analytic approaches.
Parallel median splitting and k-splitting with application to merging and sorting

Multiple-instruction multiple-data (MIMD) algorithms that use multiple processors to do median splitting, k-splitting and parallel splitting into t equal sections are presented. Both concurrent read, exclusive write (CREW) and exclusive read, exclusive write (EREW) versions of the algorithms are given. It is shown that a k-splitting problem can be easily converted into a median-splitting problem. Methods for finding multiple split points quickly and application of k-splitting to merging and sorting are discussed. >
Distributed hydrological modeling of total dissolved phosphorus transport in an agricultural landscape, part II: dissolved phosphorus transport

Abstract. Reducing non-point source phosphorus (P) loss to drinking water reservoirs is a main concern for New York City watershed planners, and modeling of P transport can assist in the evaluation of agricultural effects on nutrient dynamics. A spatially distributed model of total dissolved phosphorus (TDP) loading was developed using raster maps covering a 164-ha dairy farm watershed. Transport of TDP was calculated separately for baseflow and for surface runoff from manure-covered and non-manure-covered areas. Soil test P, simulated rainfall application, and land use were used to predict concentrations of TDP in overland flow from non-manure covered areas. Concentrations in runoff for manure-covered areas were computed from predicted cumulative flow and elapsed time since manure application, using field-specific manure spreading data. Baseflow TDP was calibrated from observed concentrations using a temperature-dependent coefficient. An additional component estimated loading associated with manure deposition on impervious areas, such as barnyards and roadways. Daily baseflow and runoff volumes were predicted for each 10-m cell using the Soil Moisture Distribution and Routing Model (SMDR). For each cell, daily TDP loads were calculated as the product of predicted runoff and estimated TDP concentrations. Predicted loads agreed well with loads observed at the watershed outlet when hydrology was modeled accurately (R2 79% winter, 87% summer). Lack of fit in early spring was attributed to difficulty in predicting snowmelt. Overall, runoff from non-manured areas appeared to be the dominant TDP loading source factor.
Vacuum and beam diagnostic controls for ORIC beam lines

Vacuum and beam diagnostic equipment on beam lines from the Oak Ridge Isochronous Cyclotron is controlled by a dedicated system. The system is based on an industrial programmable logic controller with an IBM AT personal computer providing control room operator interface. Expansion of this system requires minimal reconfiguration and programming, thus facilitating the construction of additional beam lines. Details of the implementation, operation, and performance of the system are discussed. >
Cytoreductive surgery for advanced or recurrent endometrial cancer: A meta-analysis

Abstract Objective To determine the relative effect and quantify the impact of multiple prognostic variables on median overall survival time among cohorts of patients with advanced or recurrent endometrial cancer undergoing cytoreductive surgery. Methods Fourteen retrospective cohorts with advanced or recurrent endometrial cancer (672 patients) meeting study inclusion criteria were identified. Univariate analysis was used to assess the effect on median overall survival time of multiple variables. The limited number of studies available made multivariate analysis impractical. Results Statistically significant clinical variables associated with median overall survival time were the proportion of patients undergoing complete surgical cytoreduction, adjuvant radiation, or receiving adjuvant chemotherapy. Cohort median overall survival time was positively associated with increasing proportion of patients undergoing complete surgical cytoreduction (each 10% increase improving survival by 9.3 months, p =0.04) and receiving post-operative radiation therapy (each 10% increase improving survival by 11.0 months, p =0.004), while an increasing proportion of patients receiving chemotherapy was negatively associated with survival (each 10% increase decreasing survival by 10.4 months, p =0.007). Conclusions The current analysis suggests that among patients with advanced or recurrent endometrial cancer, complete cytoreduction to no gross residual disease is associated with superior overall survival outcome. The unexpected correlation between treatment modality and survival may be a surrogate marker for more precise factors such as location of disease, performance status, or cytoreductive status post-operatively, which may have influenced the decision to administer adjuvant radiation versus chemotherapy and were not able to be controlled for given the limitations of the extracted data.