cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of Caregiver Perception of Preparedness on Burden in an Oncology Population

Purpose/objectives To identify the level of lay caregiver burden and perception of preparedness that exists for the oncology population prior to and just after hospital discharge. Design Descriptive, correlational design using repeated measures. Setting Large, tertiary care, private medical center in the midwestern United States. Sample 59 lay caregivers of patients with cancer who were discharged from inpatient hospital status. Methods Caregivers completed Robinson's Caregiver Strain Index and Archbold's Preparedness Scale questionnaires immediately prior to discharge, 7-10 days postdischarge, and 28-30 days postdischarge. Main research variables Caregivers' perception of preparedness and burden. Findings Preparedness levels ranged from "somewhat" to "pretty well" prepared and were consistent over time. Burden levels were moderate and also consistent over time. Increased levels of preparedness were associated with decreased levels of burden, and that relationship was consistent over time. Conclusions Caregivers' levels of preparedness can be enhanced, although no significant differences were reported in the period from prehospital discharge to one month following discharge. Burden experiences of caregivers are real and not affected by the transition from hospital to home. Burden experiences can be influenced by perceptions of preparedness. Implications for nursing Efforts to enhance the preparedness of lay caregivers can influence their burden experience.
Intelligence Testing: The Mystique, the Myth, the Maelstrom, and the Mandate

As a result of early events in the testing movement, the value of intelligence testing was extended beyond its intent and the psychologist was not answerable to any measure of accountability. More recently, the value of testing in the decision-making process has been challenged in the courts and is now restricted by legislative mandate. A resistance to the issue of accountability has grown among psychologists and others who assess intelligence. Continued resistance to the extant mandate may lead to an even more undesirable alternative to accountability—the demise of the standardized test.
Commentary: The need for model development related to Cladophora and nutrient management in Lake Michigan

Abstract In the past 10 to 15 years, excessive growth of Cladophora and other attached algae in the nearshore regions of Lake Michigan has re-emerged as an important resource management issue. This paper considers the question, “What information is needed to predict the response of Cladophora production in Lake Michigan to management variables, such as nutrient loading, and to additional environmental variables that are outside of management control?” Focusing on Lake Michigan, while drawing on the broader literature, we review the current state of information regarding 1) models of Cladophora growth, 2) models that simulate the physical environment, 3) models that simulate nearshore and whole-lake nutrient dynamics, with a specific focus on the role of dreissenid mussels, and 4) monitoring of Cladophora abundance. We conclude that while substantial progress has been made, considerable additional research is required before reliable forecasts of Cladophora response to nutrient loads and other environmental variables are possible. By providing a detailed outline of this complex, multidisciplinary problem, we hope that this paper will aid in coordinating collaborative research efforts toward the development of useful predictive models.
Nuclear, chloroplast, and mitochondrial DNA polymorphisms as biochemical markers in population genetic analyses of forest trees

DNA analyses have been used only occasionally to investigate genetic polymorphisms in forest tree populations. Nonetheless, these analyses have already contributed to significant discoveries, such as paternal chloroplast and maternal mitochondrial DNA inheritance in Pinaceae. DNA polymorphisms will be increasingly exploited in the future by forest population geneticists, because available technology permits large sample sizes and yields excellent resolution. The utility of chloroplast, mitochondrial, and nuclear DNA polymorphisms is expected to be greatest when less expensive genetic markers are unavailable, insufficiently numerous, or ineffectively polymorphic. For example, DNA fingerprinting may permit the unambiguous elucidation of genetic relationships within and among populations of woody species.
Probing the Cross-β Core Structure of Amyloid Fibrils by Hydrogen−Deuterium Exchange Deep Ultraviolet Resonance Raman Spectroscopy

Studying the structure of the amyloid fibril is important for understanding fibrillogenesis at a molecular level. Hydrogen−deuterium exchange deep ultraviolet resonance Raman (DUVRR) spectroscopy combined with advanced statistical analysis allowed for structural characterization of the highly ordered cross-β core of lysozyme fibrils. No inhomogeneous broadening of Raman bands due to various amino acid residues was found that might indicate a sequence-independent structure of the cross-β core. The resolved Raman signature indicated that the antiparallel β-sheet is the dominant secondary structural conformation of the core.
Application of the least squares times domain algorithm for efficient model parameter estimation

Abstract The present work will discuss the application of a finite difference equation based method for vibration modal parameter estimation. Since the method is well developed for dynamic system analysis, the mathematical development will only be briefly reviewed. The paper will concentrate on the application of the scheme for efficient and rapid estimation of structural modal parameters. A method to evaluate the quality of the modal model with respect to the original data will be presented and discussed. The testing and analysis scheme will be applied to several sets of simulated, laboratory and structural data. The results illustrate that the method can extract accurate modal parameters with as few as 200 time samples in a computationally efficient fashion. An analysis of the parameter sensitivity shows that the modal damping ratio is the most difficult to estimate. The potential for incorporating a rapid identification method into an on-site analysis scheme is discussed.
Simultaneous segmentation and iterative registration method for computing ADC with reduced artifacts from DW-MRI.

Purpose: Apparent diffusion coefficient (ADC), derived from diffusion-weighted magnetic resonance images (DW-MRI), measures the motion of water molecules in vivo and can be used to quantify tumor response to therapy. The accurate measurement of ADC can be adversely affected by organ motion and imaging artifacts. In this paper, the authors’ goal was to develop an automated method for reducing artifacts and thereby improve the accuracy of ADC measurements in moving organs such as liver. Methods: The authors developed a novel method of computing ADC with fewer artifacts, through simultaneous image segmentation and iterative registration (SSIR) of multiple b-value DW-MRI. The authors’ approach reduces artifacts by automatically finding the best possible alignment between the individual b-value images and a reference DW image using a sequence of transformations. It selects such a sequence by an iterative choice of b-value DW images based on the accuracy of their alignment with the reference DW image. The authors’ approach quantifies the accuracy of alignment between a pair of images using modified Hausdroff distance computed between the structures of interest. The structures of interest are identified by a user through strokes drawn in one or more slices in the reference DW image, which are then volumetrically segmented using GrowCut. The same structures are segmented in the remaining b-value images by transforming the user-drawn strokes through registration. The ADC values are computed from all the aligned b-value images. The images are aligned by using affine registration followed by deformable B-spline registration with cubic B-spline resampling. Results: The authors compared the results of ADC computed using their approach with ADC computed (a) without registration and (b) with basic affine registration of all b-value images to a chosen reference. The authors’ approach was the most effective in reducing artifacts compared to the other two methods. It resulted in a mean artifact ratio (fraction of voxels in a structure with negative ADC over total number of voxels in the structure) of 2.7% versus 5.4% for affine registration and 32% for no registration for >200 tumors. The authors’ approach also resulted in the lowest median standard deviation in the computed mean ADC for all tumors [0.05,0.09,0.07,0.58] compared to those from affine image registration [0.02, 0.14, 0.58, 0.79] and no image registration [0.64, 0.83, 0.83, 1.09] on tests where random displacement [8,10,12,16] pixels were introduced in multiple trials in the b-value images. Conclusions: The authors developed a novel approach for reducing artifacts in ADC maps through simultaneous registration and segmentation of multiple b-value DW images. The authors’ method explicitly employs a registration quality metric to align images. When compared to basic affine and no image registrations, the authors’ approach produces registrations of greater accuracy with lowest artifact ratio and median standard deviation of the computed mean ADC values for a wide range of displacements.
Mantle plume noble gas component in glassy basalts from Reykjanes Ridge

Basalts from the Reykjanes Ridge contain noble gases delivered from the non-degassed lower mantle by the Iceland plume. These lower mantle gases are thought to be a mixture of planetary and solar components, as would be expected if the Earth accreted from fine silicate particles.
Importance of lymph node involvement in pancreatic neuroendocrine tumors: impact on survival and implications for surgical resection.

Conflicting data exist on predictors of nodal metastases and their impact on survival in patients with pancreatic neuroendocrine tumors (PNETs). We aim to identify factors associated with lymph node involvement and evaluate the effect of nodal metastases on survival. All patients undergoing surgery for PNETs in the Surveillance, Epidemiology, and End Results (SEER) tumor registry from 1988 to 2010 were included. Predictors of lymph node involvement and disease-specific survival (DSS) were evaluated using logistic regression and Cox regression, respectively. Patients (1,915) underwent surgery for a PNET (62 % nonfunctional). Nodal positivity was associated with increasing tumor size (p < 0.001) and grade (p < 0.001). Unadjusted DSS at 5 years was 81 % for N0, 74 % for Nx, and 69 % for N1, respectively, (p < 0.001). After adjustment for tumor size and grade, DSS was significantly decreased in N1 patients (HR 1.57; 95 % CI 1.23–1.95). For patients who had at least one node examined and had low-grade PNETs <1 cm, no nodal metastases were found. High tumor grade and increasing size predict nodal metastases in patients with PNETs. N1 status is independently associated with decreased DSS. Low-grade tumors <1 cm may be observed or enucleated.
A model for solar radiation conversion to algae in a shallow pond

Abstract In recent years there has been considerable interest in solar energy utilization through bioconversion, and a promising application involves the mass culture of unicellular algae. The purpose of this study has been to develop systematic procedures for predicting the yield of such cultures as a function of geographic location and diurnal and seasonal conditions. The procedures allow for the use of available insolation data and account for both the spectral and directional characteristics of the incident radiation. Calculations for the maximum hourly production of algae and oxygen have been performed for the Indianapolis, Indiana region, and the results are in reasonable agreement with field data obtained at similar latitudes.
EFFECT OF ANTI-ASTHMATIC MEDICATIONS ON INTERLEUKIN 6 (IL-6) PRODUCTION FROM STIMULATED HUMAN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCs). 43

Although the mechanism is uncertain, elevated levels of IL-6 in bronchoalveolar lavage fluids in asthmatics suggest a possible role in the pathogenesis of pulmonary inflammation. It has been shown that aerosolized furosemide (FUR) may be helpful in the treatment of asthma, and an inhibitory effect of FUR on cytokine production in vitro has recently been shown. A comparison of its effect with other anti-asthmatic medications appears warranted. PBMCs from 25 normal subjects were isolated by density gradient centrifugation and pretreated for 20 min with varying concentrations of FUR, nedocromil sodium (NS), sodium cromoglycate (SC), or hydrocortisone acetate (HC) before LPS was added (10μg/ml). The cells (1×106 cells/ml) were incubated at 37°C for 2 days and supernatants analyzed for IL-6 by ELISA (Genzyme). FUR inhibited IL-6 production at high concentrations(>2.5×10-3 M). At a concentration of 10-2 M, IL-6 production was reduced by 98% (p<0.001) compared to 93% for HC(p<0.001). There was no effect of NS nor SC. Figure
A CRYSTALLINE PIGMENT PRODUCED FROM 2-HYDROXYPYRIDINE BY ARTHROBACTER CRYSTALLOPOIETES N.SP.

A bacterium was isolated from soil which utilizes 2-hydroxypyridine as sole source of carbon and nitrogen. When grown on solid medium with this substrate massive amounts of green rectangular crystals are deposited extracellularly in the colony mass. The pigment producing organism proved to be a hitherto undescribed species to which the name Arthrobacter crystallopoietes was applied. The pigment formed is characterized qualitatively by the following properties: it is an oxidation product of 2-hydroxypyridine probably still containing a six-membered heterocyclic ring; it exists as an anion with an intense blue color in neutral or slightly alkaline solution and as a metal salt in the deposited crystals; it precipitates from acid solution as a red water-insoluble free acid; it can be reversible oxidized and reduced, being colorless in the reduced form; and in solution it is spontaneously oxidized by air, the reaction being very rapid at alkalineph. The ultraviolet, visible and infrared spectra of the blue and red forms are presented. The properties of the pigment show that it is a member of a chemically poorly defined group of compounds termed azaquinones and that it is related to but not identical with pigments produced by the bacterial oxidation of nicotine, nicotinic acid and isonicotinic acid.
Alcian Stains for Histochemical Localization of Acid and Sulfated Polysaccharides in Algae

Alcian dyes may be used successfully to differentiate and locate sulfated and non-sulfated acid polysaccharides in algal tissues. Sulfated polysaccharides occur in Cladophora, Ulva, Taonia, Macrocy...
Resin hemoperfusion in dogs intoxicated with ethchlorvynol (Placidyl

Resin hemoperfusion in dogs intoxicated with ethchlorvynol (Placidyl®). Kinetic parameters were studied to determine the effectiveness of hemoperfusion in removing ethchlorvynol from the plasma and red blood cells (RBC) of intoxicated dogs. Perfusion columns contained polystyrene/divinyl benzene resin (XAD-4 Amberlite(®)). Column clearances of ethchlorvynol averaged 96.5 ± 0.4% of the plasma flow rate (mean ±SEM, 9 dogs). Plasma ethchlorvynol t1/2's during preperfusion periods averaged 94.1hr. During hemoperfusion, t1/2's averaged 3.8hr, or 90.3hr shorter than at the endogenous rate of detoxication. There was no significant difference between preperfusion and postperfusion half lives. An estimate based on plasma column clearance suggests that 1.5 ± 0.1g ethchlorvynol, or 19.0 ± 2.8% of the dose, was removed by hemoperfusion. The amount eluted from the resin was 2.9 ± 0.3g (37.2 ± 5.8% of the dose), or about twice the amount apparent from plasma clearance alone. Further, the volume of distribution of ethchlorvynol was 2.3 ± 0.2 liters/kg, suggesting significant distribution to intracellular and extravascular compartments. The results show that resin hemoperfusion removes a large fraction of ethchlorvynol from intoxicated dogs, and greatly adds to endogenous mechanisms for elimination. Ethchlorvynol was removed from RBC directly, and ultimately from extravascular sites as well. Hemoperfusion sur resine chez des chiens intoxiques par l'ethchlorvynol (Placidyl®). Afin de determiner l'efficacite de l'hemoperfusion dans la soustraction d'ethchlorvynol du plasma et des hematies de chiens intoxiques, les parametres cinetiques ont ete mesures. Les colonnes de perfusion contenaient une resine polystyrene/divinyl benzene (XAD-4 Amberlite®). La clearance de l'ethchlorvynol par les colonnes etait en moyenne de 96,5 ± 0,4% du debit plasmatique (moyenne ±SEM, 9 chiens). La plasmatique de l'ethchlorvynol t½'s pendant la periode prealable a la perfusion etait de 94,1 heures. Pendant l'hemoperfusion, t½'s etait en moyenne de 3,8 heures, soit 90,3 heures de moins qu'au cours de la detoxication spontanee. Il n'a pas ete observe de difference entre les demi vies avant et apres perfusion. Une estimation fondee sur la clearance des colonnes suggere que 1,5 ± 0,1g d'ethchlorvynol, soit 19,0 ± 2,8% de la dose a ete soustrait par l'hemoperfusion. La quantite eluee de la resine a ete de 2,9 ± 0,3g (37,2 ± 5,8% de la dose), soit le double de la quantite evaluee a partir de la clearance du plasma. De plus, le volume de distribution de l'ethchlorvynol etait de 2,3 ± 0,2 litres/kg, ce qui suggere une distribution importante dans les compartiments intracellulaire et extravasculaire. Les resultats montrent que l'hemoperfusion sur resine soustrait une fraction importante de l'ethchlorvynol chez des chiens intoxiques et ajoute une elimination importante aux mecanismes endogenes. L'ethchlorvynol a ete soustrait des hematies directement et finalement des sites extravasculaires aussi.
Biomechanical Effect of Annular Tears in Healthy and Degenerated Lumbar Discs

Structural alterations in the disc are accompanied by changes in disc tissue structure and composition during degeneration processes. As the lumbar disc degenerates, the disc height decreases. At the same time due to the development of fissures and cracks in the annulus, its material behavior changes. The degeneration process also includes cleft formation in the nucleus and reduction in water content in the nucleus and annulus. Porosity and drained modulus of the disc tissues are also affected by disc degeneration. The clear demarcation between nucleus and surrounding annulus slowly disappear as the disc degeneration progresses thus increasing the annulus volume while reducing the nucleus volume. Both in-vitro and finite element studies exist in literature which deals with the biomechanical effect of disc degeneration. The changes in biomechanical behavior due to degeneration are a combined effect of change in geometrical parameters of the disc, change in material characteristics of the disc components and presence of annular tears. It is not known how much of the change in disc biomechanics is due to change in disc tissue composition and due to additional tears present within the degenerated disc. The current study is thus related to the effect of such progressive changes on lumbar disc biomechanics.Copyright © 2012 by ASME
Efficient reverse skyline retrieval with arbitrary non-metric similarity measures

A Reverse Skyline query returns all objects whose skyline contains the query object. In this paper, we consider Reverse Skyline query processing where the distance between attribute values are not necessarily metric. We outline real world cases that motivate Reverse Skyline processing in such scenarios. We consider various optimizations to develop efficient algorithms for Reverse Skyline processing. Firstly, we consider block-based processing of objects to optimize on IO costs. We then explore pre-processing to re-arrange objects on disk to speed-up computational and IO costs. We then present our main contribution, which is a method of using group-level reasoning and early pruning to micro-optimize processing by reducing attribute level comparisons. An extensive empirical evaluation with real-world datasets and synthetic data of varying characteristics shows that our optimization techniques are indeed very effective in dramatically speeding Reverse Skyline processing, both in terms of computational costs and IO costs.
A mechanism for dexterous end-effector placement during minimally invasive surgery

Presented here is the design of a mechanism for dexterous placement of an end-effector during minimally invasive surgery. A literature review is presented to show that capabilities of the mechanism are unavailable in current instrumentation. Apart from actuation of the end-effector, our mechanism provides 180° bi-directional articulation relative to the support tube and rotation of the end-effector about the articulated axis. These are accomplished via a compact multi-link structure comprised of gears and gear-links that provide excellent stiffness, load capacity and durability. The structure is optimized to have a large and dexterous workspace, low backlash, and small force magnification. Maximization of load capacity and durability of the complete mechanism is achieved by the use of high strength stainless steels, gears with 25° pressure angles to accommodate larger sized teeth, optimized gear pack thicknesses to distribute stresses evenly, and a compact forceps design to reduce tip length. Resistance to pitting is improved by alternating materials and/or hardness of materials between mating parts. The instrument is capable of supporting 4.5 N needle tip loads with infinite life expectancy and loads up to 8.7 N intermittently.
Harnessing the power of multimedia in offender-based law enforcement information systems

Criminal offenders are increasingly administratively processed by automated multimedia information systems. During this processing, case and offender biographical data, mugshot photos, fingerprints and other valuable information and media are collected by law enforcement officers. As part of their criminal investigations, law enforcement officers are routinely called to solve criminal cases based upon limited evidence . . . evidence increasingly comprised of human DNA, ballistic casings and projectiles, chemical residues, latent fingerprints, surveillance camera facial images and voices. As multimedia systems receive greater use in law enforcement, traditional approaches used to index text data are not appropriate for images and signal data which comprise a multimedia database. Multimedia systems with integrated advanced pattern matching tools will provide law enforcement the ability to effectively locate multimedia information based upon content, without reliance upon the accuracy or completeness of text-based indexing.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Estimating labile particulate iron concentrations in coastal waters from remote sensing data

[1] Owing to the difficulties inherent in measuring trace metals and the importance of iron as a limiting nutrient for biological systems, the ability to monitor particulate iron concentration remotely is desirable. This study examines the relationship between labile particulate iron, described here as weak acid leachable particulate iron or total dissolvable iron, and easily obtained bio-optical measurements. We develop a bio-optical proxy that can be used to estimate large-scale patterns of labile iron concentrations in surface waters, and we extend this by including other environmental variables in a multiple linear regression statistical model. By utilizing a ratio of optical backscatter and fluorescence obtained by satellite, we identify patterns in iron concentrations confirmed by traditional shipboard sampling. This basic relationship is improved with the addition of other environmental parameters in the statistical linear regression model. The optical proxy detects known temporal and spatial trends in average surface iron concentrations in Monterey Bay. The proxy is robust in that similar performance was obtained using two independent particulate iron data sets, but it exhibits weaker correlations than the full statistical model. This proxy will be a valuable tool for oceanographers seeking to monitor iron concentrations in coastal regions and allows for better understanding of the variability of labile particulate iron in surface waters to complement direct measurement of leachable particulate or total dissolvable iron.
Quantitative high-resolution gas chromatography and mass spectrometry of toxaphene residues in fish samples.

Abstract This report describes an analytical method which permits the determination of ppb (1 μg/kg) level of toxaphene in fish tissues. Interferences both from biogenic and from xenobiotic substances are reduced even with low-resolution mass spectrometry. The methodology has a low susceptibility to false positive determinations, which could result from the presence of a wide variety of co-contaminants. The method is based on the measurement of a signal representative of the toxaphene residue ( m/z 158.9) relative to a known amount of an internal standard 37 Cl-labelled compound. A modular approach to toxaphene enrichment was permitted a moderately simple procedure, significantly reducing analytical time requirements and the number of sample manipulations, and making the procedure amenable to automation. The reliability and accuracy of the procedure are demonstrated by the results of intra- and interlaboratory studies. The methodology has been validated and the presented data indicate that the detection limit is 1 μg/kg of total toxaphene. Toxaphene recovery from fish at concentration levels between 0.1 and 10 μg/g is 84 ± 12%.
Context models in the MDL framework

Current approaches to speech and handwriting recognition demand a strong language model with a small number of states and an even smaller number of parameters. We introduce four new techniques for statistical language models: multicontextual modeling, nonmonotonic contexts, implicit context growth, and the divergence heuristic. Together these techniques result in language models that have few states, even fewer parameters, and low message entropies. For example, our techniques achieve a message entropy of 2.16 bits/char on the Brown corpus using only 19374 contexts and 54621 parameters. Multicontextual modeling and nonmonotonic contexts, are generalizations of the traditional context model. Implicit context growth ensures that the state transition probabilities of a variable-length Markov process are estimated accurately. This technique is generally applicable to any variable-length Markov process whose state transition probabilities are estimated from string frequencies. In our case, each state in the Markov process represents a context, and implicit context growth conditions the shorter contexts on the fact that the longer contexts did not occur. In a traditional unicontext model, this technique reduces the message entropy of typical English text by 0.1 bits/char. The divergence heuristic, is a heuristic estimation algorithm based on Rissanen's (1978, 1983) minimum description length (MDL) principle and universal data compression algorithm.
Considering the switch: Challenges of transitioning to non-lead hunting ammunition

In this issue of The Condor: Ornithological Applications, Haig et al. (2014) summarize negative impacts of lead ammunition and fishing tackle on birds and discuss strategies for mitigating risks to wildlife and human health. Their Review raises an important set of questions for hunters, wildlife managers, and conservation scientists. Effective mitigation will require careful understanding of technical, economic, and social dimensions of the problem. Here, I focus on challenges specific to adopting non-lead ammunition for hunting, particularly for large game animals. I discuss limitations of using the ban on lead ammunition for waterfowl hunting as an analog for reducing lead use for other types of hunting, explain important technical considerations in design and use of non-lead ammunition, and point out areas where effective non-lead alternatives are still lacking. I suggest that currently available economic analyses of the cost of non-lead alternatives are inadequate and do not recognize wide variation in hunter behavior. These considerations have strong implications for designing effective outreach and predicting responses of hunters asked to consider non-lead alternatives. Enforcing outright bans on using lead ammunition for all types of hunting, as recently enacted in California, may prove even more challenging than similar restrictions for waterfowl hunting. Despite this, I propose that major reductions in exposure of wildlife and people to lead bullet fragments are achievable, particularly through outreach and incentive programs that focus on the most commonly used types of firearms for big game hunting—high velocity modern rifles. Bullets from these widely used rifles typically produce the most lead fragments and have the best selection of effective non-lead options available at this time. Efforts to change hunter behavior must recognize the true costs and challenges of changing to non-lead ammunition. Likewise, hunters should recognize and accept their important role in wildlife conservation and work to embrace effective alternatives to lead as they become available.
Sample Size for Therapeutic Equivalence Based on Confidence Interval

In this article, the sample size calculations pertaining to a therapeutic equivalence trial based on a confidence interval are described for both normally and dichotomously distributed data. Other issues regarding equivalence trials are also discussed.
Acceleration beyond the wave speed in dissipative wave-particle systems

∗Dene Farrel contributed to this article as an REU student at the Santa Fe Institute. His REU advisor was Alfred Hubler. Alfred Hubler is the director of the Center for Complex Systems Research at the University of Illinois at Urbana-Champaign. Joseph Brewer and Ines Hubler contributed to this article during research at the Center for Complex Systems Research.; Electronic address: a-hubler@uiuc.edu
Laparoscopic appendectomy for perforated appendicitis with peritonitis.

Towfigh et al. [2] make a strong argument for using laparoscopic appendectomy to manage perforated appendicitis. A number of these cases progress to peritonitis. This subgroup was not specifically mentioned in their review. A localized perforation is relatively easy to manage laparoscopically because the local area of perforation can be quickly washed out and the appendix removed. However, when the appendix has perforated and there is associated widespread peritonitis with pelvic, gutter, subphrenic, and interloop abscesses, open management usually involves a large midline incision, a stay in the intensive care unit, respiratory failure requiring ventilation, cardiac failure requiring management, recurrent abscess formation requiring percutaneous drainage or reoperation (planned or unplanned), and significant associated mortality in those who experience multiorgan failure of 20% or more. I have now treated four patients with perforated appendicitis and associated peritonitis using laparoscopic washout with saline and Jackson-Pratt drainage, followed by intravenous antibiotics for 10 days. All the patients had a mild degree of fluid retention secondary to cardiac failure and short-term ventilator dependency of up to 36 h. One patient was reexplored after his postoperative computed tomography (CT) scan indicated a recurrent pelvic abscess (however, instead of an abscess, only a small amount of clear fluid was found between small bowel loops in the pelvis). This patient refused to undergo an interval appendectomy, but the other three patients underwent subsequent laparoscopic appendectomy arranged after an interval of 5 or 6 weeks, when they appeared to be completely recovered from their peritonitis [1]. A reduction in the length of hospital stay after laparoscopic appendectomy for perforated appendicitis is one thing, but can we go further? In cases of peritonitis secondary to perforated appendicitis, I now preferentially treat these very ill patients with laparoscopic washout, continually considering the pernicious effects of peritonitis. Should we go so far as to suggest that consideration should be given to the abandonment of open appendectomy for perforation with peritonitis?
Concerning colonization of remote coral islands

Remote coral islands are not always the idyllic concept people have of them. Some are paradise on earth, with golden sandy beaches, palms swaying in the breeze, surrounded by clear blue water. Others are barren featureless places, de void of any kind of life, or so it may seem on first encountering them. Many remote tropical islands are formed by volcanic activity when molten rock wells up through fissures in the ocean floor. The molten rock cools and solidifies. With further volcanic activity the rock builds up and eventually breaks through the ocean surface, creating a new island. Remote coral islands can be formed by accu mulation of coral in shallow water or on sub
Low-voltage op amp design and differential difference amplifier design using linear transconductor with resistor input

This paper describes a 1-V wide-input range and high linearity transconductance input stage that uses poly resistor and input-impedance boosting technique. Using the proposed transconductor, an op amp and a differential difference amplifier (DDA) were implemented in a 1.2-/spl mu/m CMOS process. The transconductor has a total harmonic distortion (THD) of less than -60 dB for an input swing of 400 mV at 10 kHz. The op amp and the DDA show a peak-to-peak output swing of 800 mV and a THD of less than -70 dB for an output swing of 600 mV at 10 kHz.
Discrepancy rates of on-call radiology residents' interpretations of CT angiography studies of the neck and circle of Willis.

OBJECTIVE. The purpose of our study was to determine the discrepancy rates of radiology residents' interpretations of emergent CT angiography (CTA) studies of the neck and circle of Willis and to assess any adverse clinical outcomes.MATERIALS AND METHODS. Five hundred thirty-eight CTA studies (287 circle of Willis and 251 neck) ordered emergently after hours and given preliminary readings by radiology residents from January 1, 2006, through December 31, 2007, were retrospectively reviewed. Discrepancies between the interpretations of radiology residents and the final reports of neuroradiology attending physicians were classified as either false-negatives (failure to recognize abnormalities) or false-positives (misinterpreting normal scans as abnormal). Discrepancies that could affect patient care or clinical care were considered major.RESULTS. Overall, the discrepancy rate was 13.6% for circle of Willis CTA and 13.5% for neck CTA. The misinterpretation rate of first-year residents was 19.5%, which was sta...
Second-harmonic generation in a nonlinear, anisotropic medium with diffraction and depletion

A general method for calculating second-order nonlinear processes in crystals is presented. This approach includes beam depletion and diffraction while permitting a spatial variation of the indices of refraction. As a particular example, second-harmonic generation in a crystal is studied. In this case the spatial variation of the indices of refraction is due to local heating of the crystal caused by the partial absorption of the fundamental beam.
Analysis of the performance characteristics of the five-channel Microtops II Sun photometer for measuring aerosol optical thickness and precipitable water vapor

Five Microtops II sun photometers were studied in detail at the NASA Goddard Space Flight Center (GSFC) to determine their performance in measuring aerosol optical thickness (AOT or Tau(sub alphalambda) and precipitable column water vapor (W). Each derives Tau(sub alphalambda) from measured signals at four wavelengths lambda (340, 440, 675, and 870 nm), and W from the 936 nm signal measurements. Accuracy of Tau(sub alphalambda) and W determination depends on the reliability of the relevant channel calibration coefficient (V(sub 0)). Relative calibration by transfer of parameters from a more accurate sun photometer (such as the Mauna-Loa-calibrated AERONET master sun photometer at GSFC) is more reliable than Langley calibration performed at GSFC. It was found that the factory-determined value of the instrument constant for the 936 nm filter (k= 0.7847) used in the Microtops' internal algorithm is unrealistic, causing large errors in V(sub 0(936)), Tau(sub alpha936), and W. Thus, when applied for transfer calibration at GSFC, whereas the random variation of V(aub 0) at 340 to 870 nm is quite small, with coefficients of variation (CV) in the range of 0 to 2.4%, at 936 nm the CV goes up to 19%. Also, the systematic temporal variation of V(sub 0) at 340 to 870 nm is very slow, while at 936 nm it is large and exhibits a very high dependence on W. The algorithm also computes Tau(sub alpha936) as 0.91Tau(sub alpha870), which is highly simplistic. Therefore, it is recommended to determine Tau(sub alpha936) by logarithmic extrapolation from Tau(sub alpha675) and Tau(sub alpha 870. From the operational standpoint of the Microtops, apart from errors that may result from unperceived cloud contamination, the main sources of error include inaccurate pointing to the Sun, neglecting to clean the front quartz window, and neglecting to calibrate correctly. If these three issues are adequately taken care of, the Microtops can be quite accurate and stable, with root mean square (rms) differences between corresponding retrievals from clean calibrated Microtops and the AERONET sun photometer being about +/-0.02 at 340 nm, decreasing down to about +/-0.01 at 870 nm.
A combined feasibility and performance macromodel for analog circuits

The need to reuse the performance macromodels of an analog circuit topology challenges existing regression based modeling techniques. A model of good reusability should have a number of independent design parameters and each parameter can vary in a large numeric range. On the other hand, these requirements can cause a large percentage of functionally incorrect designs in the design space and thus results in a sparse feasible design space. They also complicate the mathematical relationship between the performance parameters and the design parameters. In order to tackle these challenges, this paper presents a combined feasibility and performance macromodel based on support vector machines (SVMs). The feasibility model identifies the feasible designs that satisfy the design constraints. The performance macromodel is valid for feasible designs. Feasibility macromodeling is formulated as a classification problem while performance macromelting as a regression problem. An active learning scheme (Ding, et al., 2005) has been applied to improve the accuracy of the feasibility model much faster than only using uniformly distributed designs in the entire design space. The experiment of the authors showed that the performance macromodels in the feasible design space are more accurate and faster to construct and evaluate than performance macromodels in the entire design space without functional or performance constraints considered.
Towards Interference-Aware Routing for Real-time Traffic in Multi-hop Wireless Networks

We formulate the real-time routing problem in static multi-hop wireless networks as an optimization problem, whose solution is the optimal routes relative to an end- to-end delay based objective. The problem is formulated as a mixed integer linear program. The variance of the delay with respect to the aggregate interference measures is empirically studied and a linear approximation is proposed. We show that this formulation yields routes that significantly outperform the best routes obtained by OLSR. Finally, we discuss the applications of such a model both in terms of capacity analysis, on-line algorithms for static scenarios, and extensions to allow the development of distributed protocols that solve the optimization problem.
Studies on the Sequential Development and Pathogenesis of Citrinin Mycotoxicosis in Turkeys and Ducklings

The toxic effects of citrinin in turkeys and ducklings was studied in four trials. Citrinin dissolved in dimethyl sulfoxide-70% ethanol solution (3: 1, volume/volume) was administered by gavage to male turkey poults and male white Pekin ducklings. When seven-day-old ducklings were given doses of citrinin between 30 to 110 mg/kg body weight, most of the treated ducklings which died (49/80) did so within four to 12 hours. Blood samples were collected sequentially at 3, 6, 12, and 24 hours after administration from seven-day-old ducklings given the single lethal dose (LD50). The alterations included hyperkalemia (P I 0.01) and metabolic acidosis characterized by reduced blood pH (P I 0.01) and base excess (P 5 0.01). Fourteen-day-old turkeys and ducklings given 56 or 57 mg/kg, respectively, were killed at 1, 3, 6, 12, 24, 48, and 72 hours after treatment. The principal alteration in both species was nephrosis that was more severe in turkeys than in ducklings. Tubular necrosis was the dominant lesion at three to 72 hours in turkeys and at six to 24 hours in ducklings. Hepatic and lymphoid lesions occurred in both turkeys and ducklings treated with citrinin. Citrinin is a secondary metabolite of a number of fungal species belonging to the genera Penicillium and Aspergill~s.~* lo In most reports of the acute toxicity of citrinin, the principal histological lesions have been in the kidney, and the nephrotoxic effects of citrinin were considered the principal cause of death.* During our investigations of citrinin mycotoxicosis in turkey poults and ducklings, it was observed that renal lesions were prominent in the turkey, but were mild in ducklings and could not be established as the cause of death in ducklings. Because of these species variations in the severity of the renal lesions, other studies were under- taken to define the sequential development of lesions produced in turkeys and ducklings by a single lethal dose (LDSo) and to define certain clinicopathologic alterations in ducklings.
Extraction and Types of Lignin

Lignin is the most important aromatic polymer from renewable resources due to its natural abundance, robust material properties, and the fact that its use does not directly compete with the food supply. Lignin has been investigated since the late nineteenth century, but it finds limited application due to poor processability, low reactivity, and intrinsic heterogeneity depending on the plant source and isolation methods used. Current strategies for using lignin in modern materials center on integrating it with other natural or synthetic polymers. This chapter introduces diverse types of lignin according to its extraction methods from raw biomass and focuses on commercial-grade mass production technologies of lignin and the effects of these processes on its chemical characteristics.
Sequence Constraints on Folding and Binding

Understanding the structural and dynamic information encoded in the primary sequence of a protein is one of the most fundamental challenges in modern biology. Most studies of protein design and ligand binding are extremely native-state centric, ignoring the role of a protein's energy landscape. The amino acid sequence of a protein, however, encodes more than the native three-dimensional structure; it encodes the entire energy landscape - an ensemble of conformations whose energetics and dynamics are finely tuned for folding, binding and activity. I will present our results demonstrating that for proteins without a well-folded native state, small sequence variation can have dramatic effects on ligand binding and specificity. I will also present single-molecule studies demonstrating that small changes in the sequence and environment can alter the folding trajectory of a protein.
Social cues modulate free-running circadian activity rhythms in the diurnal rodent, Octodon degus

Two experiments assessed the effects of social cues and daily disturbance on the circadian locomotor activity rhythms of Octodon degus housed in constant darkness. In experiment 1, females in free-running conditions were housed alone or with entrained female partners ("donors") in cages on either side of a mesh barrier. Donors were removed daily and entrained to 1 h of light, and as a control, the cages of singly housed animals were rustled daily coincident with donor removal and replacement. None of the animals housed alone entrained to daily disturbances presented during the active phase, and seven of eight degus failed to show changes in the circadian period (tau) or phase of their rhythms. In contrast, although the presence of entrained donors did not elicit full entrainment of free-running rhythms, five of six animals demonstrated partial entrainment for 5-12 days (of 30 days), four of six altered phase of activity onset, and six of six lengthened tau of circadian rhythms. In experiment 2, females whose free-running circadian activity rhythms were at least 10 h out of phase were housed together in pairs. None of the pairs demonstrated mutual synchronization of their activity rhythms, although 8 of 12 degus modified phase of activity onset and 9 of 12 animals altered tau. We conclude social information in the absence of light, is sufficient for partial entrainment and for changes in tau and phase of free-running rhythms in this diurnal rodent.
Observation of Huge Surface Hole Mobility in the Topological Insulator Bi 0.91 Sb 0.09 (111)

We report the first direct measurement of transport properties of surface states in the topological insulator ${\mathrm{Bi}}_{0.91}{\mathrm{Sb}}_{0.09}$ (111) from the weak-field Hall effect and Shubnikov--de Haas oscillations. We find that the holelike surface band displays an unexpectedly high mobility $23\text{ }000--85\text{ }000\text{ }\text{ }{\mathrm{cm}}^{2}/\mathrm{V}\text{ }\mathrm{s}$, which is the highest mobility so far reported in bismuth-based topological insulators. This result provides the first quantitative assessment of the effect of alloy disorder on the mobility of surface states in topological insulators. We show that the 9% alloy disorder decreases the mobility of surface states by a factor of less than 2.3.
Effect of Drugs on Gastric Motility Following Vagotomy

ConclusionsDeath of rabbits one or 2 days after cervical vagotomy occurred as reported by Short4 and others. During the first several hours after operation the animals seemed in good condition and stomach motility ceased. Levin5 has described this as “shock.” Motility recovered later and persisted as described by Opuls,6 Auer7 and others. Van Yzeren8 noted chronic gastric ulcers in rabbits after vagotomy and this has been confirmed by others and by us.In man gastric contractions were markedly depressed after vagotomy even though resting intragastric pressure increased slightly. These effects persisted. Ulcers healed or became quiescent. This difference in the effect of vagotomy, that is, healing of ulcer in man and development of ulcer in rabbits might be associated with decreased motility in man and increased or continued motility in rabbits.Of the drugs studied (Table I) most restored motility or tone during the first hours after vagotomy in rabbits. In patients Urecholine was the most effective. Starr ...