cssi/SciSciGPT-SciSciNet huggingface dataset:
Model-based analysis of multiple electrode array stimulation for epiretinal visual prostheses.

Objective. Epiretinal stimulation, which uses an array of electrodes implanted on the inner retinal surface to relay a representation of the visual scene to the neuronal elements of the retina, has seen considerable success. The objective of the present study was to quantify the effects of multi-electrode stimulation on the patterns of neural excitation in a computational model of epiretinal stimulation. Approach. A computational model of retinal ganglion cells was modified to represent the morphology of human retinal ganglion cells and validated against published experimental data. The ganglion cell model was then combined with a model of an axon of the nerve fiber layer to produce a population model of the inner retina. The response of the population of model neurons to epiretinal stimulation with a multi-electrode array was quantified across a range of electrode geometries using a novel means to quantify the model response—the minimum radius circle bounding the activated model neurons as a proxy for the evoked phosphene. Main results. Multi-electrode stimulation created unique phosphenes, such that the number of potential phosphenes can far exceed the number of electrode contacts. Significance. The ability to exploit the spatial and temporal interactions of stimulation may be critical to improvements in the performance of epiretinal prostheses.
Spectral instability of the semiclassical Zakharov–Shabat eigenvalue problem

Abstract We present some brief numerical results indicating that in the semiclassical limit the Zakharov–Shabat eigenvalue problem exhibits severe spectral instability, and that small changes in the potential can result in large changes in the spectrum.
Angiotensin II stimulation of granuloma macrophage phagocytesis and actin polymerization in murine schistosomiasis mansoni

Abstract In murine Schistosomiasis, components of the renin-angiotensin system are present in isolated liver granulomas. Furthermore, granuloma macrophages have receptors for angiotensin II (AII). These observations with other evidence suggest that angiotensins function in immunoregulation. Since AII can stimulate actin-myosin interactions and since macrophages have contractile proteins, it was determined whether AII could alter the phagocytic activity of granuloma macrophages. AII, at concentrations which saturate AII receptors, enhanced phagocytic activity for both unopsonized and opsonized sheep red blood cells (RBC). Using a DNase inhibitory assay, it was also shown that similar concentrations of AII stimulated intracellular actin polymerization. Cytochalasin B, which impedes actin filament interactions, inhibited AII-stimulated phagocytosis. AII analogs, with little-known agonist activity, blocked AII-stimulated actin polymerization and phagocytosis of RBC and RBC opsonized with IgG. These data support the contention that AII binds to AII receptors on the macrophage and stimulates phagocytosis possibly through polymerization of intracellular actin.
Increasing ultraviolet light exposure is associated with reduced mortality from Clostridium difficile infection

BackgroundClostridium difficile infection (CDI) is an increasingly common cause of inpatient mortality. Vitamin D deficiency is associated with more aggressive CDI. We aimed to determine if average annual ultraviolet light (UV) exposure was associated with mortality in patients with CDI.MethodsWe used the US National Inpatient Sample (NIS) from 2004–2011 to assess the mortality risk in patients with a diagnosis of CDI (as per ICD-9CM 008.45). Annual average state UV exposure was assigned to each hospitalization. Logistic regression was used to determine the effects of UV exposure on mortality, controlling for age, gender, race and other comorbidities.ResultsDuring the study period, there were 2.61 million hospitalizations with a diagnosis of CDI. The mortality rate was 9.0%. In univariate analysis, the odds ratio (OR) of inpatient mortality for the UV index was 0.97 (95% CI 0.95–0.99; p = 0.008) per unit of UV exposure. In a multivariable model adjusting for age, gender, race, Charlson-Deyo index, season ...
Intracoronary shunt-induced endothelial cell damage in porcine heart.

Background Injury to and dysfunction of the endothelium can compromise the patency of coronary arteries and lead to impaired perfusion of the heart. Such injury can occur after the application of an intravascular shunt and/or a snare to a coronary artery during bypass surgery. In this study, multiphoton microscopy was used to assess the integrity of endothelium in porcine coronary arteries subjected to shunting and snaring during off-pump coronary artery bypass grafting (OPCAB). Materials and methods In open chest porcine, the left anterior descending artery was manipulated in different regions using snare and shunt to simulate OPCAB. Sections of left anterior descending artery were labeled with fluorescent dyes to evaluate the viability of the endothelium. The structural integrity of the endothelium was evaluated by calcein- and ethidium homodimer-mediated fluorescence. Endothelial functional viability was assessed by measuring cellular esterase activity, calcium mobilization, and endothelial nitric oxide synthase-mediated generation of nitric oxide using fluorescence dyes and multiphoton microscopy. Results Substantial endothelial damage was observed in shunted region of the coronary arteries. In contrast, endothelium remained structurally viable in regions that were snared, similar to control regions of the coronary arteries that were not manipulated. Esterase activity, calcium mobilization, and nitric oxide generation was greater in the control and snared regions of the coronary arteries in comparison to the shunted region. Conclusions The use of intracoronary shunts led to structural damage and attenuation of endothelial function in porcine coronary arteries, whereas snared vessels maintained their viability and integrity, similar to the control sections. The routine use of shunts in OPCABG may lead to endothelial damage and possibly to long-term graft failure.
Drug Delivery Into the Eye With the Use of Ultrasound

Objective. To evaluate ultrasound enhancement of drug delivery through the cornea and the histologic appearance of the cornea up to 24 hours after treatment. Methods. Corneas were exposed to ultrasound at a frequency of 880 kHz and intensities of 0.19 to 0.56 W/cm 2 (continuous mode) with an exposure duration of 5 minutes. The aqueous humor concentration of a topically applied hydrophilic dye, sodium fluorescein, was determined quantitatively in ultrasound- and sham-treated rabbit eyes in vivo. Gross and light microscopic examinations were used to observe structural changes in the cornea 0 to 24 hours after ultrasound exposure. Cavitation activity was measured with a passive cavitation detector. Results. Most cells with an appearance different from that of the normal cells were present in the surface layer of the corneal epithelium. No structural changes were observed in the stroma. The increase in dye concentration in the aqueous humor (relative to sham treatment), after the simultaneous application of ultrasound and the dye solution, was 2.4 times at 0.19 W/cm 2 , 3.8 times at 0.34 W/cm 2 , and 10.6 times at 0.56 W/cm 2 (P <.05). Dye delivery was found to increase with increasing ultrasound intensity, which corresponded to an increase in cavitation activity. Corneal pits, observed in the ultrasound-treated epithelium, completely disappeared within 90 minutes. Conclusions. Application of 880-kHz ultrasound provided up to 10-fold enhancement in the delivery of a hydrophilic compound through the cornea while producing minor changes in the corneal epithelium.
Studying copy number variations using a nanofluidic platform

Copy number variations (CNVs) in the human genome are conventionally detected using high-throughput scanning technologies, such as comparative genomic hybridization and high-density single nucleotide polymorphism (SNP) microarrays, or relatively low-throughput techniques, such as quantitative polymerase chain reaction (PCR). All these approaches are limited in resolution and can at best distinguish a twofold (or 50%) difference in copy number. We have developed a new technology to study copy numbers using a platform known as the digital array, a nanofluidic biochip capable of accurately quantitating genes of interest in DNA samples. We have evaluated the digital array's performance using a model system, to show that this technology is exquisitely sensitive, capable of differentiating as little as a 15% difference in gene copy number (or between 6 and 7 copies of a target gene). We have also analyzed commercial DNA samples for their CYP2D6 copy numbers and confirmed that our results were consistent with those obtained independently using conventional techniques. In a screening experiment with breast cancer and normal DNA samples, the ERBB2 gene was found to be amplified in about 35% of breast cancer samples. The use of the digital array enables accurate measurement of gene copy numbers and is of significant value in CNV studies.
Evaluating the obtunded patient after cardiac surgery: the role of continuous electroencephalography

Abstract Purpose This prospective study was designed to evaluate the role of continuous electroencephalography (EEG) in the management of adult patients with neurological dysfunction early after cardiac surgery. Materials and Methods Seven hundred twenty-three patients undergoing cardiac surgery between December 2010 and June 2011 were divided into 2 groups based on the presence or absence of post-operative neurological dysfunction. All patients with neurological dysfunction underwent continuous EEG. Results Neurological dysfunction was diagnosed in 12 patients (1.7%), of whom 5 (42%) did not regain consciousness after surgery, 4 (33%) had a clinical event suspicious for seizure and 3 (25%) had neurological deficits. Continuous EEG showed that 2 of the 5 patients who failed to regain consciousness, without clinical signs of seizures, were in electrographic non-convulsive focal status epilepticus. Periodic discharges were present in the continuous EEGs of 3 patients. Three additional patients (25%) had abnormal movements that continuous EEG demonstrated was not due to seizure activity. Conclusions Non-convulsive status epilepticus may be an under-recognized cause of obtundation early after cardiac surgery. Continuous EEG monitoring is a non-invasive test that can identify patients that may benefit from anti-epileptic medication. Larger comparative studies are required to establish whether this leads to significant improvements in patient outcomes.
Simulation Detection in Handwritten Documents by Forensic Document Examiners

This study documents the results of a controlled experiment designed to quantify the abilities of forensic document examiners (FDEs) and laypersons to detect simulations in handwritten documents. Nineteen professional FDEs and 26 laypersons (typical of a jury pool) were asked to inspect test packages that contained six (6) known handwritten documents written by the same person and two (2) questioned handwritten documents. Each questioned document was either written by the person who wrote the known documents, or written by a different person who tried to simulate the writing of the person who wrote the known document. The error rates of the FDEs were smaller than those of the laypersons when detecting simulations in the questioned documents. Among other findings, the FDEs never labeled a questioned document that was written by the same person who wrote the known documents as "simulation." There was a significant statistical difference between the responses of the FDEs and layperson for documents without simulations.
Making Modelica Applicable for Formal Methods

Engineers need to perform many different types of analyses as they design systems. Modelica has become a leading language to support numerical simulation. As a consequence there is widespread understanding of Modelica and a large number of Modelica model libraries available. This paper addresses the task of using formal methods to derive system properties such as whether a design meets its requirements for all possible inputs. We report on our experience building a qualitative reasoner operating on Modelica models. In this paper, we highlight five Modelica modeling practices that impede the application of formal methods.
Advertising and Internet Content Providers: Creating a Market for Information

This article develops a conceptual framework that enables researchers to view the Internet as a market for information. Advertising plays a critical role in sustaining the viability of this market. Advertising has found itself increasingly under fire by academics and general public opinion. New ways are conceptualized for marketers to view information and a conceptual framework is developed that links advertising to information and information to economic growth. Public policy and managerial implications of this framework are discussed.
MARINE RESERVES ARE NECESSARY BUT NOT SUFFICIENT FOR MARINE CONSERVATION

The intensity of human pressure on marine systems has led to a push for stronger marine conservation efforts. Recently, marine reserves have become one highly advocated form of marine conservation, and the number of newly designated reserves has increased dramatically. Reserves will be essential for conservation efforts because they can provide unique protection for critical areas, they can provide a spatial escape for intensely exploited species, and they can potentially act as buffers against some management miscalculations and unforeseen or unusual conditions. Reserve design and effectiveness can be dramatically improved by better use of existing scientific understanding. Reserves are insufficient protection alone, however, because they are not isolated from all critical impacts. Communities residing within marine reserves are strongly influenced by the highly variable conditions of the water masses that continuously flow through them. To a much greater degree than in terrestrial systems, the scales of fundamental processes, such as population replenishment, are often much larger than reserves can encompass. Further, they offer no protection from some important threats, such as contamination by chemicals. Therefore, without adequate protection of species and ecosystems outside reserves, effectiveness of reserves will be severely compromised. We outline conditions under which reserves are likely to be effective, provide some guidelines for increasing their conservation potential, and suggest some research priorities to fill critical information gaps. We strongly support vastly increasing the number and size of marine reserves; at the same time, strong conservation efforts outside reserves must complement this effort. To date, most reserve design and site selection have involved little scientific justification. They must begin to do so to increase the likelihood of attaining conservation objectives.
Differentiation of the Endometrial Macrophage during Pregnancy in the Cow

Background: The presence of conceptus alloantigens necessitates changes in maternal immune function. One player in this process may be the macrophage. In the cow, there is large-scale recruitment of macrophages expressing CD68 and CD14 to the uterine endometrium during pregnancy. Methodology/Principal Findings: In the present study, the function of endometrial macrophages during pregnancy was inferred by comparison of the transcriptome of endometrial CD14 + cells isolated from pregnant cows as compared to that of blood CD14 + cells. The pattern of gene expression was largely similar for CD14 + cells from both sources, suggesting that cells from both tissues are from the monocyte/macrophage lineage. A total of 1,364 unique genes were differentially expressed, with 680 genes upregulated in endometrial CD14 + cells as compared to blood CD14 + cells and with 674 genes downregulated in endometrial CD14 + cells as compared to blood CD14 + cells. Twelve genes characteristic of M2 activated macrophages (SLCO2B1,GATM,MRC1,ALDH1A1,PTGS1, RNASE6, CLEC7A, DPEP2, CD163, CCL22, CCL24 ,a ndCDH1) were upregulated in endometrial CD14 + cells. M2 macrophages play roles in immune regulation, tissue remodeling, angiogenesis and apoptosis. Consistent with a role in tissue remodeling, there was overrepresentation of differentially expressed genes in endometrium for three ontologies related to proteolysis. A role in apoptosis is suggested by the observation that the most overrepresented gene in endometrial CD14 + cells was GZMA. Conclusions: Results indicate that at least a subpopulation of endometrial macrophages cells differentiates along an M2 activation pathway during pregnancy and that the cells are likely to play roles in immune regulation, tissue remodeling, angiogenesis, and apoptosis.
Flow and stability of helium II between concentric cylinders

We discuss our present knowledge of the flow and stability of helium II between concentric cylinders. The flow problem for helium II leads us to consider the formation of quantized vortices in the uniform rotation of helium II in an open bucket as well as quantized circulation states and vortices in a rotating annulus. We then consider how to treat the first appearance of vortices in the presence of shear, which allows us to characterize the basic flow which must be examined for stability. The results suggest an explanation for heretofore unexplained experiments. Future directions for research on the stability of helium II are suggested.
Evidence from international capital markets that accounting practices affect market return

This paper presents evidence that differences in accounting practices among countries have an effect on firm value. The long-window model of Easton et al. (1992) is used to establish a relationship between market return and accounting return for a sample of firms in seven countries: Australia, Canada, France, Germany, Great Britain, Japan and the United States. This relationship is estimated cross-sectionally to allow for country differences to arise in error terms from the valuation. Some differences occur for all countries at some point, but the most striking differences are for France and Great Britain. These results support concerns about accounting standards affecting international market integration and they suggest that further work should be done to determine which accounting standards are responsible for the effects.
Effects of Board Demography and Directors' Incentives on Corporate Greenmail Decisions

This study explored the extent to which a board of director's demographic characteristics and the financial incentives of its outside members influence a company's decision to privately repurchase ...
OC24.04: Echocardiographic predictors of acute recipient twin demise following selective fetoscopic laser photocoagulation for twin‐twin transfusion syndrome

Results: Eleven CDH fetuses, 9 CDH+TO and 20 controls were suitable for the study. CDH fetuses showed significantly higher PI (8.0 (SD 1.8) vs. 5.22 (SD 1.1) p<0.001) and lower FMBV (13.5% (SD 4.6) vs. 23.0% (SD 2.1) p<0.001) than controls. In contrast, CDH-TO fetuses had significantly lower PI (5.8 (SD 2.3) vs. 8.0 (SD 1.8) p=0.015) and higher FMBV (27.6% (SD 7.1) vs. 13.5% (SD 4.6) p<0.001) than CDH fetuses, with values similar to controls. PEDRF and PSV showed non significant differences among the study groups. The lung to body weight ratio (LBWR) at necropsy correlated positively with lung FMBV (r=0.60 p<0.001) and negatively with pulmonary artery PI (r= −0.48 p<0.01). Conclusion: Tracheal occlusion is consistently associated with increased lung tissue perfusion and decreased intrapulmonary impedance in a rabbit model of CDH.
DISTRIBUTION AND INNERVATION OF FACIAL BRISTLES AND HAIRS IN THE FLORIDA MANATEE (TRICHECHUS MANATUS LATIROSTRIS)

The distribution and anatomy of sirenian perioral bristles (modified vibrissae) and facial hairs are of interest because of their use during feeding and tactile exploration. In the present study we have identified six fields of perioral bristles on the face of the Florida manatee (T. manatus latirostris), four (U1-U4) on each side of the upper lips and oral cavity, and two (L1-L2) on each side of the lower lip pad, inside the oral cavity and rostral to the horny mandibular pad. Each field has a characteristic location, number of bristles, and range of bristle length and diameter. There is a mean of 110 (± 19) bristles per side, with no left-right differences. Branches of the infraorbital nerve innervate the bases of the largest bristles (U2 group) on the upper bristle pad, and the inferior alveolar nerve supplies the bristles of the lower bristle pad. The dorsal and ventral buccal branches of the facial nerve innervate the superficial facial musculature, which is likely to be involved in bristle eversion and other movements which constitute feeding behavior. Hair is denser in the facial region than on the remainder of the body. Within the face, hair is denser on the oral disk than on the supradisk. The oral disk contains bristle-like hair, whereas the supradisk region possesses hair that is similar in length and diameter to that on the postcranial body. The mean total of bristles and hairs per face was 1,942. Means for the subregions were 220 (± 39) bristles on the perioral bristle pads, 601 (± 115) bristlelike hairs in the oral disk region, 710 (± 229) typical hairs in the supradisk region, and 411 (± 108) typical hairs on the chin. There were no significant differences between left and right side counts. Facial hair density was inversely correlated with facial area and body size. These data provide new information on the anatomical basis of the exceptional orofacial activities characteristic of manatees during feeding and tactile exploration.
Deletion and site-specific mutagenesis of nucleolin's carboxy GAR domain

Vertebrate nucleolin is an abundant RNA-binding protein in the dense fibrillar component of active nucleoli. Nucleolin is modular in composition. Its amino-terminal third contains alternating acidic and basic domains, its middle section contains four consensus RNA-binding domains (cRBDs), and its carboxy-terminus contains a distinctive glycine/arginine-rich (GAR) domain with several RGG motifs. The arginines within these motifs are asymmetrically dimethylated. Several laboratories have shown that the GAR domain is necessary but not sufficient for the efficient localization of nucleolin to nucleoli. We examined the distribution of endogenous fibrillarin, Nopp140, and B23 when full-length and ΔGAR nucleolin were expressed exogenously as enhanced green fluorescent protein (EGFP)-tagged fusions. Only B23 redistributed when ΔGAR-EGFP was expressed at moderate to high levels, suggesting an in vivo interaction between nucleolin and B23. Next we substituted all ten arginines within the GAR domain of Chinese hamster ovary (CHO) nucleolin with lysines to test the hypothesis that methylation of the carboxy GAR domain is necessary for the nucleolar association of nucleolin. The lysine-substituted mutant was not an in vitro substrate for the yeast protein methyltransferase, Hmt1p/Rmt1. It was, however, able to associate properly with interphase nucleoli and with interphase pre-nucleolar bodies upon recovery from hypotonic shock. We conclude, therefore, that although the GAR domain is necessary for the efficient localization of nucleolin to nucleoli, methylation of this domain is not required for proper nucleolar localization.
Fast turn around post process yield enhancement for custom VLSI foundries

An effective fast-turnaround postprocess yield-enhancement methodology for custom VLSI which has been developed using a static random access memory (SRAM) and a test element group (TEG) yield vehicle is described. The SRAM/TEG is combined on a single chip providing a unified process-control vehicle. Several examples of visual defect classification using SRAM failure analysis and nonvisual defect characterization from the electrical test monitors are presented. Application of the methodology to yield enhancement efforts for a 1.25- mu m process is presented showing excellent correlation of SRAM and custom circuit yields with a 100* defect density reduction over a two-year period. >
Within-host dynamics of antigenic variation

Genomes of some parasites contain dozens of alternative and highly diverged surface antigens, of which only a single one is expressed in any cell. Individual cells occasionally change expression of their surface antigen, allowing them to escape immune surveillance. These switches appear to occur in a partly random way, creating a diverse set of antigenic variants. In spite of this diversity, the parasitemia develops as a series of outbreaks, in which each outbreak is dominated by relatively few antigenic types. Host-specific immunity eventually clears the dominant antigenic types, and a new outbreak follows from antigenic types that have apparently been present all along at low frequency. This pattern of sequential dominance by different antigenic types remains unexplained. We review the five most prominent theories, which have developed mainly from studies of the protozoans Trypanosoma and Plasmodium, and the bacterial spirochete Borrelia. The most promising theories depend on some combination of mechanisms to create favored connectivity pathways through the matrix of transitions between variants. Favored pathways may arise from biased switches at the molecular level of gene expression or from biases imposed by immune selection. We illustrate the concept of connectivity pathways by reanalysis of data on transitions between variants from Borrelia hermsii.
Using clinical significance in psychotherapy outcome research: The need for a common procedure and validity data

It is recommended that an estimate of clinical significance be included in all psychotherapy outcome studies and that this estimate be based on the work of Jacobson and Truax (1991). The concept of clinical significance is defined and put in the context of broadly accepted statistical methods along with its advantages and a rationale for using the Jacobson methods. One implication of this recommendation is that the use of the term will have a standard meaning. Examples of loss of meaning are provided and suggest that conclusions about best practices will be affected unless such a voluntary step is taken. Some problems with the concept of clinical significance are noted and a call for validity studies is made.
Obesity, outcomes and quality of care: body mass index increases the risk of wound-related complications in colon cancer surgery

BACKGROUND: Obese patients may face higher complication rates during surgical treatment of colon cancer. The aim of this study was to measure this effect at a high-volume tertiary care center. METHODS: All patients with colon cancer treated surgically at a single center from 2004 through 2011 were reviewed. Multivariate regression assessed relationships of complications and stay outcomes with body mass index (BMI) controlling for age, gender, comorbidity score, surgical approach, and history of smoking. RESULTS: In 1,048 included patients, BMI was a predictor of several complications in both laparoscopic and open procedures. For every increase of BMI by one World Health Organization category, the odds ratios were 1.61 (P ,.001) for wound infection and 1.54 (P ,.001) for slow healing. Additionally, right colectomies had an odds ratio of 3.23 (P 5 .017) for wound dehiscence. No further associations with BMI were found. CONCLUSIONS: BMI was incrementally associated with wound-related complications, illustrating how the proliferation of obesity relates to a growing risk for surgical complications. As the surgical community strives to improve the quality of care, patient-controllable factors will play an increasingly important role in cost containment and quality improvement.
Transport limitation of nutrient uptake in phytoplankton1

When single-celled phytoplanktonic organisms absorb nutrients from impoverished water they may deplete a region around them of nutrient and become transport limited in their uptake rates. A criterion is derived, based on the solution to the diffusion equation for a spherical cell with a surface absorption rate given by an equation of the Monod form, by which the importance of transport limitation may be ascertained. The criterion can be applied to organisms for which half-saturation constants and maximum uptake rates are known for specified nurients. It can be broadened to include the influence of motility. Application to a list of organisms for which uptake kinetics data are available showed that transport limitation could be significant for some organisms, and that for at least one motile organism motility could not entirely eliminate the influence of transport on uptake rate.
Interleukin 6 production during cardiac surgery correlates with increasing age

Abstract Background Cardiac surgery produces a proinflammatory response characterized by cytokine production. Proinflammatory cytokines such as interleukin 6 (IL-6) may contribute to morbidity and mortality after cardiopulmonary bypass (CPB). Elderly patients undergoing CPB are at increased risk of morbidity and mortality. We hypothesized that patients aged >70 y produce more IL-6 during CPB. Methods Twenty-three patients (ages 23–80) undergoing cardiac surgery had blood sampled from the ascending aorta and coronary sinus on initial cannulation for bypass, at 30 min of aortic cross-clamp time, on release of the aortic cross–clamp, and at 20 min after reperfusion. Group 1 patients ( n = 8) were aged n = 7) were aged between 60 and 70 y, and group 3 patients ( n = 8) were aged >70 y. Plasma levels of tumor necrosis factor-alpha, IL-1, and IL-6 were analyzed. Results The three groups did not differ with respect to preoperative ejection fraction, New York Heart Association classification, mean aortic cross-clamp time, or mean CPB time. IL-6 levels rose throughout myocardial ischemia and reperfusion in all three age groups. The increase in IL-6 during ischemia and reperfusion in the age group >70 was greater than the increase in younger patients. IL-6 was similar in the coronary sinus and the ascending aorta. Conclusions These data suggest that patients aged >70 y undergoing cardiac operations generate more IL-6 during CPB. The increased circulating IL-6 in elderly patients may incite a proinflammatory state that could subsequently underlie the associated higher mortality and morbidity of these procedures in elderly patients.
Monte Carlo study of radiation-induced demagnetization using the two-dimensional Ising model

Abstract A simple radiation-damage model based on the Ising model for magnets is proposed to study the effects of radiation on the magnetism of permanent magnets. The model is studied in two dimensions using a Monte Carlo simulation, and it accounts for the radiation through the introduction of a localized heat pulse. The model exhibits qualitative agreement with experimental results, and it clearly elucidates the role that the coercivity and the radiation particle’s energy play in the process. A more quantitative agreement with experiment will entail accounting for the long-range dipole–dipole interactions and the crystalline anisotropy.
Endothelial cell interactions with sickle cell, sickle trait, mechanically injured, and normal erythrocytes under controlled flow.

Increased adhesive forces between sickle erythrocytes and endothelial cells (EC) have been hypothesized to play a role in the initiation of vasoocclusion in sickle cell anemia. Erythrocyte/human umbilical vein EC interactions were studied under controlled flow conditions for normal (AA), homozygous sickle cell (SS). sickle cell trait (AS). mechanically injured normal, and “high-reticulocyte control” RBC by using video microscopy and digital image processing. The number of adherent RBC was determined at tenminute intervals during a washout period. Results indicate that SS RBC were more adherent than AA RBC. Mechanically injured (sheared) AA RBC were also more adherent than control normal cells but less adherent than SS RBC. AS RBC did not differ significantly in their adhesive properties from normal RBC. Less-dense RBC were more adherR BC-ENDOTHELIAL CELL (EC) interactions may be important in the vasoocclusive phenomena observed in sickle cell disease. Evidence has been presented by several investigators that suggests that sickle cells adhere mally to EC under static conditions as well as under uncontrolled conditions of flow.� The abnormal adherence of sickle cells has been correlated with the vasoocclusiveseverity of the disease.7 Interactions between blood cells and endotheflal surfaces in blood vessels occur under dynamic conditions. Flow inhibition or promotion of blood cell adhesion to the endothelium may occur depending on the velocity and morphology of the moving cells. Presumably, cells in the vicinity #{224}f the endotheliumthat are moving slowly would have a greater chance of making contact and interacting with
Regulation of apical K channels in rat cortical collecting tubule during changes in dietary K intake

Long-term adaptation to a high-K diet is known to increase the density of conducting secretory K (SK) channels in the luminal membrane of the rat cortical collecting tubule (CCT). To examine whethe...
Late results of the surgical treatment of syringomyelia.

97 patients with syringomyelia were treated surgically during the last 12 years. Only those patients in which the disease showed rapid progression in the last 1/2–1 year were operated. Of these 97 patients 54 were followed for 5 years or longer.
The Sharpsburg, Kentucky, earthquake of 27 July 1980

The Sharpsburg, Kentucky, earthquake was the second largest earthquake to have occurred in the United States, east of the Continental Divide, in the past 20 yr, having a seismic moment of 4.1 × 1023 dyne-cm. A surface-wave focal mechanism study defines a nodal plane striking N30°E, dipping 50°SE, and a nearly vertical nodal plane striking N60°W. P -wave first motion data indicate right-lateral motion on the nodal plane striking N30°E, with the pressure axes oriented east-west. These angles can be varied by ±10° without affecting the fit to the surface-wave data. The surface-wave solution is reinforced by a modeling of long-period seismograms at regional distances. The P, pP , and sP polarities and amplitudes from the short-period vertical component array stack at NORSAR are used together with six unambiguous short-period P -wave first motions recorded in North America to test whether it is possible to constrain focal mechanism solutions with such data. These solutions are compatible with the surface-wave solution. Waveform modeling of the NORSAR data suggests a source pulse duration of 1.0 sec and constrains the depth to 12.0 km. To match mb estimates from NORSAR and Canadian stations, t *, for teleseismic P , must be 0.7 and 0.5, respectively, when the synthetics are scaled using the surface-wave seismic moment. In spite of extensive coverage of the epicentral zone, fewer than 70 aftershocks were recorded. The largest aftershock and an mbLg = 2.2. Aftershock locations suggest that the nodal plane striking N30°E is the fault plane. An aftershock area of 30 to 50 km2 implies a stress drop of 2.8 to 6 bars and a dislocation of 2.0 to 3.4 cm. Because of the variety of studies performed, this earthquake is presently the best-studied eastern North American seismic event with well-constrained estimates of focal depth, focal mechanism and seismic moment, and indications of the duration of the source time function and upper mantle P -wave t *.
The Medicare Catastrophic Coverage Act of 1988 Reasons For Its Premature Failure

At the time of its passage, the Medicare Reimbursement Act of 1988 was hailed as a major improvement in health care funding for the elderly. However, within a year the Act had been repealed largely through the efforts of the elderly citizens in was designed to benefit. This paper examines the problems associated with the funding methods used in this program. It suggests that interaction of the tax surcharge contained in it with other tax provision affecting the elderly made the effects of the law especially objectionable and that future programs for funding national health care program must avoid these effects if they are to succeed.
An Application of Poincaré's Recurrence Theorem to Academic Administration

(1981). An Application of Poincare's Recurrence Theorem to Academic Administration. The American Mathematical Monthly: Vol. 88, No. 1, pp. 32-33.
Myocardial T1 mapping for patients with implanted cardiac devices using wideband inversion recovery spoiled gradient echo readout.

Purpose To develop and validate a technique for myocardial T1 mapping in patients with implantable cardioverter defibrillators (ICDs). Methods A MOLLI-based pulse sequence, named Wideband-FLASH-MOLLI, was developed by incorporating a fast low angle shot (FLASH) readout and a wideband inversion pulse. The performance of Wideband-FLASH-MOLLI was evaluated using phantom studies and validated in eight healthy volunteers and ten patients with ICDs at 1.5 Tesla. Comparisons were made between Wideband-FLASH-MOLLI, FLASH-MOLLI, and bSSFP-MOLLI sequences. Results In phantom studies, the maximum T1 estimation errors using Wideband-FLASH-MOLLI with and without an ICD were less than 3% for T1 range from 212 to 1673 ms. In all healthy volunteers, there was no significant native myocardial T1 estimation difference using Wideband-FLASH-MOLLI before and after the external attachment of an ICD to the body coil (1178 ± 27 ms versus 1174 ± 33 ms; P = 0.41). Due to the presence of an ICD, the magnitude images acquired using bSSFP-MOLLI and FLASH-MOLLI showed severe artifacts within the myocardium. In contrast, no or negligible device-induced artifacts were noted within the myocardial regions of the healthy volunteers or the patients with ICDs when using Wideband-FLASH-MOLLI. Conclusion This study demonstrates the feasibility of using Wideband-FLASH-MOLLI to mitigate image artifacts and to produce accurate myocardial T1 maps in patients with ICDs. Magn Reson Med 77:1495–1504, 2017. © 2016 International Society for Magnetic Resonance in Medicine
NEWLY DESCRIBED HYPOGEOUS FUNGI AND THE MYCORRHIZAE THEY FORM IN VITRO. I. MARTELLIA MEDLOCKII SP. NOV. (RUSSULACEAE)

A new species of Martellia (hypogeous Russulaceae) from Oregon is described along with its cultural
Heparin is an anionic hydrated anticoagulant.

The major objective of this symposium is to seek substances and procedures by which blood can be kept flowing. The major determinant of whether blood continues to circulate or grows sluggish and forms an intravascular gel is the colloidal stability of fibrinogen (7, 8). Although fibrinogen constitutes only about 3–6% of total plasma protein, it is the dominant one in viscosity and gel formation (3). Fibrinogen continues to circulate normally as long as it carries a moderate negative charge and minimal degree of hydration on both its negative and positive polar sites. Reduction in either charge or hydration causes progressive shifts toward hypercoagulability, with increased surfactant property of the fibrinogen as it is driven from the plasma onto formed elements, vascular walls (4), and any other surface in or exposed to plasma. Progressive destabilization of fibrinogen causes marked increase in blood viscosity; aggregation and segregation of platelets, then of leukocytes, and then of red cells (Knisely sludging) (13); and finally disseminated intravascular coagulation. Dintenfass and Forbes (10) have shown increased viscosity of blood and plasma in many conditions in which gross hypercoagulability is later evident.
Metal Tools and the Transformation of an Oceanic Exchange System

The introduction of European technologies transformed some key aspects of traditional Pacific Island lifeways and exchange systems. One of the most dramatic changes was the replacement of shell and stone tools with those made from iron. As European explorers and traders ventured throughout Micronesia, metal commodities became highly sought after by indigenous peoples. An example of metal tools replacing traditional technologies is presented to explain how this culture contact ultimately changed one of the most famous exchange systems in the Pacific—the quarrying of stone money by Yapese Islanders in the Palau archipelago. The first iron tools ever found in excavation at a stone money quarry site are discussed in relation to their role in changing this unique interisland exchange system during the 18th and 19th centuries.
Discriminative Properties of Hippocampal Hypoperfusion in Marijuana Users Compared to Healthy Controls: Implications for Marijuana Administration in Alzheimer's Dementia

BACKGROUND Few studies have evaluated the impact of marijuana use on regional cerebral blood flow. OBJECTIVE To determine whether perfusion in specific brain regions on functional neuroimaging, including those affected by Alzheimer's disease pathology, are abnormal in marijuana users compared to controls. METHOD Persons with a diagnosis of cannabis use disorder by DSM-IV and DSM-V criteria (n = 982) were compared to controls (n = 92) with perfusion neuroimaging with SPECT at rest and at a concentration task. Perfusion estimates were quantified using a standard atlas. Cerebral perfusion differences were calculated using one-way ANOVA. Diagnostic separation was determined with discriminant analysis of all subjects. Feature selection with a minimum redundancy maximum relevancy (mRMR) identified predictive regions in a subset of marijuana users (n = 436) with reduced psychiatric co-morbidities. RESULTS Marijuana users showed lower cerebral perfusion on average (p < 0.05). Discriminant analysis distinguished marijuana users from controls with correct classification of 96% and leave one out cross-validation of 92%. With concentration SPECT regions, there was correct classification of 95% with a leave-one-out cross validation of 90%. AUC analysis for concentration SPECT regions showed 95% accuracy, 90% sensitivity, and 83% specificity. The mRMR analysis showed right hippocampal hypoperfusion on concentration SPECT imaging was the most predictive in separating marijuana subjects from controls. CONCLUSION Multiple brain regions show low perfusion on SPECT in marijuana users. The most predictive region distinguishing marijuana users from healthy controls, the hippocampus, is a key target of Alzheimer's disease pathology. This study raises the possibility of deleterious brain effects of marijuana use.
TWO CASES OF ACUTE RETINAL NECROSIS DUE TO VARICELLA ZOSTER DESPITE PRIOR SHINGLES VACCINATION

Purpose To review two cases of acute retinal necrosis in adults due to varicella zoster virus despite prior shingles vaccination. Methods Retrospective chart review. Patients A 62-year-old man and a 64-year-old man with unilateral acute retinal necrosis who had shingles vaccinations 16 and 7 months before their ocular symptoms. Results Polymerase chain reaction confirmation of varicella zoster virus in the anterior chambers of both patients. Both patients had good responses to oral antiviral therapy and topical and/or oral steroids. Discussion These two cases demonstrate that singles vaccination is not an absolute protection against varicella zoster virus-related acute retinal necrosis. However, such vaccination may reduce the severity of the acute retinal necrosis.
Model-based Pricing: Do Not Pay for More than What You Learn!

While a lot of work has focused on improving the efficiency, scalability, and usability of machine learning (ML), little work has studied the cost of data acquisition for ML-based analytics. Datasets are already being bought and sold in marketplaces for various tasks, including ML. But current marketplaces force users to buy such data in whole or as fixed subsets without any awareness of the ML tasks they are used for. This leads to sub-optimal choices and missed opportunities for both data sellers and buyers. In this paper, we outline our vision for a formal and practical pricing framework we call model-based pricing that aims to resolve such issues. Our key observation is that ML users typically need only as much data as needed to meet their accuracy goals, which leads to novel trade-offs between price, accuracy, and runtimes. We explain how this raises interesting new research questions at the intersection of data management, ML, and micro-economics.
Emergency Medicine Myths: Computed Tomography of the Head Prior to Lumbar Puncture in Adults with Suspected Bacterial Meningitis – Due Diligence or Antiquated Practice?

Abstract Background Various sources purport an association between lumbar puncture and brainstem herniation in patients with intracranial mass effect lesions. Several organizations and texts recommend head computed tomography (CT) prior to lumbar puncture in selected patients. Objective To review the evidence regarding the utility of obtaining head CT prior to lumbar puncture in adults with suspected bacterial meningitis. Discussion Observational studies report a risk of post-lumbar puncture brainstem herniation in the presence of intracranial mass effect (1.5%) that is significantly lower than that reported among all patients with bacterial meningitis (up to 13.3%). It is unclear from existing literature whether identifying patients with intracranial mass effect decreases herniation risk. Up to 80% of patients with bacterial meningitis experiencing herniation have no CT abnormalities, and approximately half of patients with intracranial mass effect not undergoing lumbar puncture herniate. Decision rules to selectively perform CT on only those individuals most likely to have intracranial mass effect lesions have not undergone validation. Despite recommendations for immediate antimicrobial therapy prior to imaging, data indicate an association between pre-lumbar puncture CT and antibiotic delays. Recent data demonstrate shortened door-to-antibiotic times and lower mortality from bacterial meningitis after implementation of new national guidelines, which restricted generally accepted CT indications by removing impaired mental status as imaging criterion. Conclusions Data supporting routine head CT prior to lumbar puncture are limited. Physicians should consider selective CT for those patients at risk for intracranial mass effect lesions based on decision rules or clinical gestalt. Patients undergoing head CT must receive immediate antibiotic therapy.
Abrikosov and the path to understanding high-Tc superconductivity

An early attempt to try to understand the high superconducting transition temperatures in the cuprate super-conductors was Abrikosov's theory of extended Van Hove singularities. It was based on our early experimental data on the YBa2Cu3O6.9 and YBa2Cu4O8 compounds which showed an extended saddle point singularity in the dispersion of the electronic excitations. This appeared to lead to a Van Hove singularity in the density of states with a divergence stronger than the known logarithmic one observed in conventional materials. The consequent high density of states of the extended singularity was thought to lead to high Tc's in a conventional BCS mechanism. Unfortunately, it was soon realized that the very incoherent nature of the electronic excitations in these materials did not provide the expected high density of states. Here we summarize the many unusual characteristics of the electronic excitations in the cuprates, and what they imply for a possible theoretical description of high-temperature superconductivity.