cssi/SciSciGPT-SciSciNet huggingface dataset:
Progress in laser risk reduction for 1 micron lasers at GSFC

In recent years, lasers have proven themselves to be invaluable to a variety of remote sensing applications. LIDAR techniques have been used to measure atmospheric aerosols and a variety of trace species, profile winds, and develop high resolution topographical maps. Often it would be of great advantage to make these measurements from an orbiting satellite. Unfortunately, the space environment is a challenging one for the high power lasers that would enable many LIDAR missions. Optical mounts must maintain precision alignment during and after launch. Outgassing materials in the vacuum of space lead to contamination of laser optics. Electronic components and optical materials must survive the space environment, including a vacuum atmosphere, thermal cycling, and radiation exposure. Laser designs must be lightweight, compact, and energy efficient. Many LIDAR applications require frequency conversion systems that have never been designed or tested for use in space. For the last six years the National Aeronautical and Space Administration (NASA) has undertaken a program specifically directed at addressing the durability and long term reliability issues that face space-borne lasers. The effort is shared between NASA Goddard Space Flight Center in Greenbelt, Maryland, and NASA Langley Research Center in Hampton, Virginia. This paper is an overview of the issues facing space-borne lasers and the efforts that Goddard has been pursuing to address them.
CHEMILUMINESCENCE OF TETRAKIS‐(DIMETHYLAMINO)‐ETHYLENE

— The dependence of the chemiluminescence intensity of tetrakis-(dimethylamino)-ethylene (TDE) on the concentration of TDE and methanol activator has been shown to be to the second power for each compound. In addition to being activated by methanol, a quenching rate constant of 9.3 times 108/M/sec for methanol on the excited state of TDE was shown to cause a decrease of chemiluminescence intensity at high concentrations. Chemical reactions of TDE di-cation in basic solutions indicated that a disproportionation occurs which produces a 50 per cent yield of TDE. On the basis of the kinetics and chemistry of TDE, a mechanism of chemiluminescence is proposed in which the excited state of TDE is produced by a bisdimethylaminocarbene dimerization.
Subclinical histopathological changes in the oculomotor nerve in diabetes mellitus

To provide reference values for the oculomotor nerve, for example, fascicular area and myelinated fiber (MF) number and size distribution, in pathological states, and to determine whether oculomotor nerves from diabetic patients without a history of oculomotor palsy have subclinical structural alterations, the morphometric features of 15 control subjects and eight diabetic patients were evaluated at a proximal and a distal level. On average the control nerves had a fascicular area of 2.7 mm2, 22,311 MF, and a bimodal diameter distribution with peaks at approximately 5 to 6 and 10 to 11 microns and a range of 2 to 20 microns. In proximal nerve, glial bundles were found in one-half of the subjects and patients, with a peak of MF sizes that differed from fibers in nonglial areas. The nerves from diabetic patients departed from the nerves from control subjects in the following two respects: changed size distribution, suggesting atrophy of fibers, and microfasciculation of edge fibers in parts of the fascicles in one-half of the patients. We conclude that glial bundles are probably a normal variant. Microfasciculation occurred much more frequently in nerves from diabetic patients and may represent subclinical injury of unknown cause. The alteration in size distribution may reflect the diabetic state and is not necessarily a precursor to diabetic ophthalmoplegia.
Situational anxiety and blood pressure lability in the physician's office.

In order to evaluate the association between situational anxiety levels and blood pressure variability during physician's office visits, 19 patients were assessed at the beginning of the visit and before and after being examined by the physician. Assessment included blood pressure measurement as well as self-report of current anxiety level. Previous findings that systolic readings do significantly diminish over the course of the visit were replicated for both hypertensive and normotensive patients, accompanied by correlative decreases in state anxiety. Diastolic blood pressure readings were more stable and less associated with fluctuations in state anxiety, except in patients with initially higher diastolic readings. Results were interpreted as indicating the importance of using more than one blood pressure measurement in diagnosing hypertension and monitoring its management. In particular, patients’ anxiety responses upon entering the examining room may produce artificial elevations.
Different transport routes for high density lipoprotein and its associated free sterol in polarized hepatic cells.

We analyzed the intracellular transport of HDL and its associated free sterol in polarized human hepatoma HepG2 cells. Using pulse-chase protocols, we demonstrated that HDL labeled with Alexa 488 at the apolipoprotein (Alexa 488-HDL) was internalized by a scavenger receptor class B type I (SR-BI)-dependent process at the basolateral membrane and became enriched in a subapical/apical recycling compartment. Most Alexa 488-HDL was rapidly recycled to the basolateral cell surface and released from cells. Within 30 min of chase at 37°C, ∼3% of the initial cell-associated Alexa 488-HDL accumulated in the biliary canaliculus (BC) formed at the apical pole of polarized HepG2 cells. Even less Alexa 488-HDL was transported to late endosomes or lysosomes. The fluorescent cholesterol analog dehydroergosterol (DHE) incorporated into Alexa 488-HDL was delivered to the BC within a few minutes, independent of the labeled apolipoprotein. This transport did not require metabolic energy and could be blocked by antibodies against SR-BI. The fraction of cell-associated DHE transported to the BC was comparable when cells were incubated with either Alexa 488-HDL containing DHE or with DHE bound to methyl-β-cyclodextrin. We conclude that rapid, nonvesicular transport of sterol to the BC and efficient recycling of HDL particles underlies the selective sorting of sterol from HDLs in hepatocytes.
Induction of human prostaglandin endoperoxide H synthase-2 (PHS-2) mRNA by TCDD.

Abstract Numerous transcription response elements (e.g. AP-1, AP-2, GRE, CREB, as well as DRE) have been identified in the transcription regulation region of the PHS-2 gene in both mouse and human. The discovery of a DRE in the region raised the possibility that PHS-2 could be induced by TCDD, a dioxin compound. The time course and dose dependence of TCDD induction of PHS-2 mRNA expression were observed in HUVEC, primary human epithelial cells. In the observed time range (0–24 hours) the steady-state mRNA expression levels of PHS-2, as well as of mRNA for CYPlA1, increased with time at a TCDD dose of 20 nM. At the 24 hour time point, TCDD-treated cells displayed significant dose-dependent elevation of PHS-2 over the range of 0–40 nM TCDD. The increases in PHS-2 mRNA in both the time course and dose dependence experiments were consistent with that of CYPIAI. In contrast, mRNA for PHS-1, the constitutively expressed isoform of PHS, did not show significant changes under the conditions tested. These results are the first to indicate that TCDD can elevate PHS-2 mRNA level in a time and dose dependent manner. Further work needs to be done to learn the molecular mechanism of activation of PHS-2 by TCDD and the relation of TCDD action with other regulatory factors in the control of PHS-2 expression.
Ballistic resistance of double-layered armor plates

Abstract In this paper, the ballistic resistance of double-layered steel shields against projectile impact at the sub-ordnance velocity is evaluated using finite element simulations. Four types of projectiles of different weight and nose shapes are considered, while armor shields consist of two layers of different materials. In a previous study of the same authors, it was shown that a double-layered shield of the same metal was able to improve the ballistic limit by 7.0–25.0% under impact by a flat-nose projectile, compared to a monolithic plate of the same weight. Under impact by a conical-nose projectile, a double-layered shield is almost as capable as a monolithic plate. The present paper extends the analysis to double-layered shields with various metallic material combinations. The study reveals that the best configuration is the upper layer of high ductility and low strength material and the lower layer of low ductility and high strength material. This configuration results in some 25% gain in the ballistic limit under moderate detrimental impact. This research helps clarify the long standing issue of the ballistic resistance of the multi-layered armor configuration.
Sound production by North Atlantic right whales (Eubalaena glacialis) in surface active groups.

The surface active group (SAG) is the most commonly observed surface social behavior of North Atlantic right whales. Recordings were made from 52 SAGs in the Bay of Fundy, Canada between July and September, from 1999 to 2002. The call types recorded from these groups were similar to those described previously for Southern right whales (Eubalaena australis), with six major call types being termed scream, gunshot, blow, upcall, warble, and downcall. The percentage of total calls of each call type depended on the group size and composition. The most common call type recorded was the scream call. The scream calls were produced by the focal female in a SAG. Production of other sound types can be attributed to whales other than the focal female, with gunshot and upcalls produced by males, and warble calls produced by female calves. The source levels for these sounds range from 137 to 162 dB rms re 1 μPa-m for tonal calls and 174 to 192 dB rms for broadband gunshot sounds.
Eosinophilic granuloma of C4 causing spinal cord compression

A rare case of vertebral eosinophilic granuloma (C4) causing spinal cord compression is reported. The clinical, histological and radiological features of this pathological entity are discussed. After surgery a complete neurological recovery was observed. The value, in selected cases, of surgical treatment with total removal of the tumour and reconstruction of the spine to ensure spinal stability and to prevent irreversible neurological deficit is emphasized.
Allosteric regulation of HIV-1 reverse transcriptase by ATP for nucleotide selection.

BACKGROUND: Human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) is a DNA polymerase that converts viral RNA genomes into proviral DNAs. How HIV-1 RT regulates nucleotide selectivity is a central issue for genetics and the nucleoside analog RT inhibitor (NRTI) resistance of HIV-1. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that an ATP molecule at physiological concentrations acts as an allosteric regulator of HIV-1 RT to decrease the K(m) value of the substrate, decrease the k(cat) value, and increase the K(i) value of NRTIs for RT. Computer-assisted structural analyses and mutagenesis studies suggested the positions of the ATP molecule and NRTI-resistance mutations during a catalytic reaction, which immediately predict possible influences on nucleotide insertion into the catalytic site, the DNA polymerization, and the excision reaction. CONCLUSIONS/SIGNIFICANCE: These data imply that the ATP molecule and NRTI mutations can modulate nucleotide selectivity by altering the fidelity of the geometric selection of nucleotides and the probability of an excision reaction.
Honey bee-native bee competition: focal point for environmental change and apicultural response in Australia

Do honey bees compete for food with other bee species in nature? This question has been the focus of considerable scientific and political attention in recent years, especially, but not exclusively in Australia. In this article we provide the background and rationale of the argument and present scientific studies which have attempted to provide evidence. We also suggest some approaches to dealing with real issues related to honey bee competition, bee conservation, and honey bee management.
Increased urinary mevalonic acid excretion in patients with abetalipoproteinemia and homozygous hypobetalipoproteinemia

Abstract Previous reports in which cholesterol homeostasis has been examined in patients with phenotypic abetalipoproteinemia have shown an increase in whole body cholesterol synthesis when measured by sterol balance techniques but normal rates of cholesterol synthesis when measured by isotopic cholesterol turnover. Recent studies have indicated that increases in cholesterol biosynthesis are paralleled by increases in the plasma concentrations of mevalonic acid and by higher rates of excretion of mevalonic acid in the urine. In the present report we have measured the 24-h urinary excretion of mevalonic acid in 7 patients with phenotypic abetalipoproteinemia and compared this to control subjects. Urinary excretion of mevalonic acid was significantly higher in the patients with abetalipoproteinemia (57.2 ± 10.2 nmol/kg body weight per day, mean ± SEM) as compared to control subjects (23.1 ± 1.5 nmol/kg per day). The magnitude of the increase in urinary mevalonic acid excretion seen in patients with abetalipoproteinemia (148%) is greater than the increase in whole body cholesterol biosynthesis assessed by sterol balance techniques (57% increase). Our results serve to further validate the usefulness of urinary mevalonate as an indicator of relative rates of cholesterol biosynthesis in humans and suggest that this measurement provides a valuable means to potentially screen for disorders associated with an oversynthesis of cholesterol.
Two and three dimensional modeling of fluidized bed with multiple jets in a DEM–CFD framework

Abstract Fluidized beds with multiple jets have widespread industrial applications. The objective of this paper is to investigate the jet interactions and hydrodynamics of a fluidized bed with multiple jets. Discrete element modeling coupled with in-house CFD code GenIDLEST has been used to simulate a bed with nine jets. The results are compared with published experiments. Mono dispersed particles of size 550 μm are used with 1.4 times the minimum fluidization velocity of the particles. Both two and three dimensional computations have been performed. To the best of our knowledge, the results presented in this paper are the first full 3D simulations of a fluidized bed performed with multiple jets. Discrepancies between the experiment and simulations are discussed in the context of the dimensionality of the simulations. The 2D solid fraction profile compares well with the experiment close to the distributor plate. At higher heights, the 2D simulation over-predicts the solid fraction profiles near the walls. The 3D simulation on the other hand is better able to capture the solid fraction profile higher up in the bed compared to that near the distributor plate. Similarly, the normalized particle velocities and the particle fluxes compare well with the experiment closer to the distributor plate for the 2D simulation and the freeboard for the 3D simulation, respectively. A lower expanded bed height is predicted in the 2D simulation compared to the 3D simulation and the experiment. The results obtained from DEM computations show that a 2D simulation can be used to capture essential jetting trends near the distributor plate regions, whereas a full scale 3D simulation is needed to capture the bubbles near the freeboard regions. These serve as validations for the experiment and help us understand the complex jet interaction and solid circulation patterns in a multiple jet fluidized bed system.
Hypothalamic hamartomas: seven cases and review of the literature

Hypothalamic hamartomas constitute rare developmental lesions associated with gelastic epilepsy and/or precocious puberty (PP). We elected to review cases encountered at our center (7 patients) and the existing literature (277 patients) to obtain a better understanding of the clinical aspects, pathogenesis, and treatment of this entity. Evidence suggests that gelastic seizures are due to intrinsic epileptogenicity. The cause of the subsequent development of other seizure types, cognitive decline, and diffuse spike-and-wave pattern remains unresolved and is addressed. Anticonvulsants often fail to control seizures and different surgical options are available. Available evidence suggests that a resection through a subtemporal approach is best for lesions that are pedunculated or with a significant prepontine component, while a transcallosal approach is more appropriate for sessile lesions with an intraventricular component. Gamma knife surgery may be especially useful for small sessile lesions, failed partial resections, or patients not appropriate or refusing open surgery.
Simulation of ventricular fibrillation in a three-dimensional model of heart

A 3-D model is reconstructed from an isolated dog heart and discretized into 1473 elements. By incorporating the details of activation of nearest neighbors, velocity of propagation, and refractoriness of previously excited tissue, electrical propagation in normal heart is simulated. Excitation by six to ten extrastimuli results in a self-sustaining random activity considered equivalent of ventricular fibrillation (VF). This model reproduces some known experimental observations and predicts induction of VF by recurrent excitation and dispersion of refractory states in cardiac elements. >
Oncogene jun encodes a sequence-specific trans- activator similar to AP-1

Proto-oncogenes encode proteins with three main sites of action: the cell-surface membrane, the cytoplasm and the nucleus. Although the exact biochemical function of most proto-oncogene products is not understood, several of them are known to be involved in signal transduction. A role in gene regulation through DNA binding has been suggested for a recently isolated member of the group of oncogenes acting at the nucleus, v-jun. The C-terminus of the putative v-jun-encoded protein is similar in sequence to the C-terminus of the yeast transcriptional activator GCN4 (refs 8, 9), which forms its minimal DNA-binding domain. GCN4 binds to specific sites whose consensus sequence is highly similar to the recognition sequence of the mammalian transcriptional activator AP-1 (refs 12, 13). Like GCN4, AP-1 binds to promoter elements of specific genes and activates their transcription. Because of the similarity between the recognition sites for GCN4 and AP-1, we examined the possibility that AP-1 could be the product of the c-jun proto-oncogene. The experimental results reported here indicate that the JUN oncoprotein is a sequence-specific transcriptional activator similar to AP-1.
Procedural and Substantive Fairness in Risk Decisions: Comparative Risk Assessment Procedures1

The issue of fairness often is central within environmental policy debates. The recent proliferation of state and local comparative risk projects for informing the selection of environmental policy priorities offers an appropriate setting to explore the issue of procedural fairness in risk-based decisionmaking. This paper describes and evaluates the process by which one of the initial state comparative risk projects, Washington's “Environment 2010,” attempted to include a broader range of participants in identifying, assessing, and generating preferred management strategies for a wide range of environmental hazards. The Washington case study suggests that comparative risk projects can be fairer procedurally, but that significant barriers remain. Noting that greater procedural fairness does not necessarily produce greater substantive fairness, the paper concludes that more attention needs to be directed at the process by which comparative risk projects translate their consensus upon risk priorities into subsequent actions.
Microvascular angiogenesis and the renin-angiotensin system

The renin-angiotensin system is one of the major regulatory mechanisms essential for maintaining cardiovascular homeostasis. Angiotensin II is a multifunctional hormone that plays a key role in regulating this system. The importance of the renin-angiotensin system in controlling sodium homeostasis and vascular resistance is well established, however, in the past decade, much attention has been focused on the importance of angiotensin II as a regulator of microvessel density, acting through the AT1 and AT2 receptors. In this review, we discuss the connections between the renin-angiotensin system and other growth factor pathways known to be involved in pathologic and physiologic angiogenesis and rarefaction.
AIDS and the Black Death.

Sir, Cohn and Weaver1 assert that recent publications suggesting that the medieval Black Death could be responsible for the origin of the CCR5-Δ32 allele2–4 are mistaken. They say: ‘scientists … have assumed that the north-south European geographical cline in the frequency of the CCR5-Δ32 allele among present-day descendents parallels the severity of the Black Death in 1348 …’ and ‘it is erroneous to assert that the plague mortalities exhibit a north–south cline; rather the opposite seems to be the case’. It is unclear who is supposed to have made these assumptions, or asserted this north–south cline. Published research indicates such assumptions to be unsubstantiated and counter to modern Black Death understanding. Cohn and Weaver argue that …
Cyclic nucleotide phosphodiesterases as targets for treatment of haematological malignancies

The cAMP signalling pathway has emerged as a key regulator of haematopoietic cell proliferation, differentiation and apoptosis. In parallel, general understanding of the biology of cyclic nucleotide PDEs (phosphodiesterases) has advanced considerably, revealing the remarkable complexity of this enzyme system that regulates the amplitude, kinetics and location of intracellular cAMP-mediated signalling. The development of therapeutic inhibitors of specific PDE gene families has resulted in a growing appreciation of the potential therapeutic application of PDE inhibitors to the treatment of immune-mediated illnesses and haematopoietic malignancies. This review summarizes the expression and function of PDEs in normal haematopoietic cells and the evidence that family-specific inhibitors will be therapeutically useful in myeloid and lymphoid malignancies.
Effect of antimicrobial proteins from porcine leukocytes on Staphylococcus aureus and Escherichia coli in comminuted meats

Study is aimed to elucidate the effect of porcine leukocyte antimicrobial protein on the proliferation of Staphylococcus aureus and Escherichia coli inoculated in ground meats. The antimicrobial proteins were isolated from porcine blood using 0.2 M sodium acetate extraction and cation-exchange column chromatography. Antimicrobial protein preparation consisted predominantly of 7.5 and 6 kDa molecules. Immunoblotting demonstrated that the 7.5 kDa molecule displayed defensin immuno-reactivity, a unique blood granulocyte antimicrobial protein. Both 7.5 and 6 kDa molecules could decrease apparent proliferation of test cultures. Sterilization (121 °C, 30 min) and proteolytic enzymes (pepsin, trypsin, and chymotrypsin) could significantly decrease bacteriocidal activities of antimicrobial protein preparation. Furthermore, antimicrobial protein preparation enhanced exposure of intercellular nucleotide of test cultures. Antimicrobial protein preparation inhibition of S. aureus and E. coli growth was concentration and time dependence. Adding 160 μg/g antimicrobial protein preparation to ground ham meat and sausage mince could significantly (P<0.05) hurdle viable colony formation of test cultures at 6 and 12 h, respectively. Taken together, porcine leukocyte antimicrobial protein preparation has potential to inhibit proliferation of S. aureus and E. coli inoculated in ground meat via induction of bacterolysis, suggesting this antimicrobial protein preparation be an alternative natural bio-preservation source for ground meat products.
The Evolution of Institutions in the Malian Cotton Sector: An Application of John R. Commons's Ideas

Applying John R. Commons's institutional economic framework, this paper analyzes the evolution of key institutions in the Malian cotton sector, starting with Mali's independence in 1960 to the ongoing market-oriented reforms in the 2000s. In accordance with Commons's economic theory, institutional changes in the Malian cotton sector have led to both intended and unintended consequences, impacting economic performance at the farm, gin, and state levels. This has, in turn, contributed to the emergence of new limiting factors. At present, lack of adequate technical advising, indebtedness, issues related to input access, discordance between farmers and their union leader representatives, unreasonable seed cotton prices, delays in payment, and low cotton yields are the current limiting factors to desired economic performance. Based on these findings, we draw policy recommendations for revitalizing the Malian cotton sector.
A CEREBELLAR DISORDER IN CHICKS, APPARENTLY OF NUTRITIONAL ORIGIN

Growing chicks maintained on a diet consisting of milk powder, casein, starch, yeast, cod liver oil, salts and filter paper develop ataxia, tremors, retraction or twisting of the head, clonic spasms of the legs, and stupor. These symptoms may appear suddenly, usually between the 18th and 25th day, and may end in death. If recovery takes place, the chicks may go on to normal development. Definite lesions are found in the cerebellum of the affected chicks. These consist of edema, necrosis and hemorrhages. Hyaline thrombi are found in the capillaries in and about the degenerated areas.
Image Quality Determines Differences in Reading Performance and Perceived Image Quality with CRT and Hard-Copy Displays

The effects of physical image quality on reading and on perceived image quality from CRT and hard-copy (photograph) displays were studied. The results showed that as the image quality of a display increased, indicated by an increase in the value of the modulation transfer function area (MTFA), the reading speed and subjective image quality ratings increased. This change in reading speed and perceived image quality occurred similarly for both hard-copy and soft-copy conditions. If the image qualities of the displayed text are similar, hard-copy and soft-copy displays will yield equivalent reading speeds.
Ruptured thoracic aneurysm presenting as dyspnea and hypotension

A 65-year-old woman with a two-day history of progressive back pain presented with acute dyspnea, tachypnea, hypotension, and tachycardia. The patient was being treated for chronic obstructive lung disease and long-standing hypertension. She evidenced unilateral diminished breath sounds and wheezing. A portable chest radiograph in the emergency department revealed a large left pleural effusion. A hemothorax was confirmed by thoracentesis, and a 7-cm descending thoracic aortic aneurysm was demonstrated by angiography. The patient underwent successful surgical resection and Dacron ® graft repair of the aneurysm. This case emphasizes the need for maintaining a high index of suspicion for atypical presentations of ruptured thoracic aneurysms and for using diagnostic thoracentesis in pleural effusions of unknown etiology.
Cover Picture: Polyaniline Nanofibers Prepared by Dilute Polymerization (Adv. Mater. 13/2005)

The cover image shows a scanning electron micrograph of polyaniline/camphorsulfonic acid nanofibers synthesized using dilute polymerization. The inset shows isolated branched nanofibers with diameters of 17–50 nm. On p. 1679, Chiou and Epstein report the preparation of these polyaniline nanofibers with controlled diameters via reducing the concentrations of both monomer and oxidant.
Negative Surface Ionization of Complex Molecules

THE formation of negative ions by the surface ionization of gases on hot metallic filaments has been used as a means of determining electron affinities. In the method of Sutton and Mayer1, the total negative ion current and the total electron current were measured as functions of temperature, by means of a magnetron. This technique has been refined by Page2 and extended to more complex molecules3. In the absence of mass analysis, the process giving rise to the negative ions is postulated a priori and justified on the basis of reasonableness and internal consistency.
Fat‐free mass as a determinant of left ventricular mass in children: The Muscatine Study

To assess the relationship of somatic growth to heart growth, associations were examined among body composition, blood pressure, androgens, sexual maturation, and left ventricular mass (LVM) during early puberty in 123 children, 7-12 years of age. All subjects underwent anthropometry, random-zero blood pressure measurements, hormone determination of androgens, physician's examination to determine sexual maturation, and echocardiographic examinations. Subjects then repeated these procedures 1 year later. Data were examined cross-sectionally (year 1, year 2) and longitudinally (Δ = year 2 minus year 1). The strongest correlations with LVM were among weight and fat-free mass (FFM) (r = 0.60 to 0.83). In males, cross-sectional predictors of LVM were FFM and stage of sexual maturation (r2 = 0.49 to 0.65). Δ LVM was best predicted in males by Δ testosterone and Δ weight (r2 = 0.22). In females, FFM was the strongest cross-sectional predictor of LVM (r2 = 0.70). Δ LVM was best predicted in females by Δ FFM and Δ height (r2 = 0.27). When males and females were pooled, gender did not predict LVM in any of the models. The results suggest that FFM is an important predictor of LVM in circumpubertal children. Boys and girls do not significantly differ in LVM once normalized for FFM. © 1996 Wiley-Liss, Inc.
Computed tomography in the evaluation of orbital infections

Abstract Two cases of orbital infection are presented and the Computed Tomographic findings are reviewed. CT proves to be an indispensable aid in the diagnosis and treatment of an orbital abscess. The importance of coronal sections and intravenous contrast enhancement in the diagnosis of orbital abscess i, emphasized.
A cinemusicaliterary analysis of the American dream as represented by biographical jazz comedepictions in the golden age of Hollywood biopics: Blow, Horatio, Blow; O, Jakie, O; Go,Tommy, Go; No, Artie, No:

This essay argues that our grasp of marketing theory benefits from an awareness of the rags-to-riches ethos that characterizes the paradigmatic American Dream. In this connection, the essay presents a cinemusicaliterary analysis of how this success-story ideal has shaped some artistic manifestations of the consumer culture in ways that have appeared conspicuously in various literary, cinematic, and musical creations. Thus, beginning with the literary works of Horatio Alger and their reification of the rags-to-riches prototype, the essay traces the evolution of this success-story paradigm through its cinematic embodiment in The Jazz Singer (1927) to its appearance in the underlying musical structures that characterize five comedepictions of jazz heroes during the golden age of Hollywood biopics: The Fabulous Dorseys (1947); The Glenn Miller Story (1954); The Benny Goodman Story (1955); The Five Pennies (1959); and The Gene Krupa Story (1959). The essay ends by considering an instructive counterexample base...
Aging and Down Syndrome: Implications for Physical Therapy

The number of people over the age of 60 years with lifelong developmental delays is predicted to double by 2030. Down syndrome (DS) is the most frequent chromosomal cause of developmental delays. As the life expectancy of people with DS increases, changes in body function and structure secondary to aging have the potential to lead to activity limitations and participation restrictions for this population. The purpose of this update is to: (1) provide an overview of the common body function and structure changes that occur in adults with DS as they age (thyroid dysfunction, cardiovascular disorders, obesity, musculoskeletal disorders, Alzheimer disease, depression) and (2) apply current research on exercise to the prevention of activity limitations and participation restrictions. As individuals with DS age, a shift in emphasis from disability prevention to the prevention of conditions that lead to activity and participation limitations must occur. Exercise programs appear to have potential to positively affect the overall health of adults with DS, thereby increasing the quality of life and years of healthy life for these individuals.
Plant Mitochondrial Electron Transfer and Molecular Biology.

Severa1 types of reduced carbon com- pounds, including fatty acids, organic acids, and amino acids, can serve as the primary reducing substrates for plant respi- ration. However, the most common substrate used by plant tissues for respiration is carbohydrate (CHpO). The complete oxidation of a carbohydrate releases a large amount of free energy, much of which is coupled to the conversion of ADP and Pi to ATI? When sucrose (Cl2H=0,1) is the substrate, aer- obic respiration can be divided into three distinct phases: glycolysis, the tricarboxylic acid (TCA) cycle, and the coupled processes of mitochondrial electron transfer and ATP synthe- sis. Except for glycolysis, all of the metabolic steps of aerobic respiration take place in the mitochondrion. Like mitochon- dria found in other eukaryotes, plant mitochondria are roughly spherical subcellular organelles that usually range from
Structure and properties of a model oxide-supported catalyst under redox conditions: WOx/α-Fe2O3 (0001)

Abstract Relaxed structures and the related electronic environments of atomic monolayers and half-monolayers of tungsten with varying degrees of oxidation on the (0001) surface of hematite (α-Fe2O3) are modeled using first-principles density functional theory (DFT). This report focuses on the effect of nominally oxidizing and reducing chemical environments on surface structure and chemistry. By considering the position of W atoms relative to the substrate, calculated surface structures are compared to synchrotron X-ray standing wave (XSW) imaging results recently reported for this system. The question of W valence state, previously reported as nominally W5+ or W6+ in reducing or oxidizing surroundings, respectively, is addressed and discussed in light of X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (XAFS) results to clarify the relationship between valence state, oxygen coordination, and bond lengths.
Practical considerations in RLCK crosstalk analysis for digital integrated circuits

Inductance and inductive crosstalk has become an important new concern for on-chip wires in deep-submicron integrated circuits. Recent advances in extractors to include inductance make possible the extraction of coupled RLCK interconnect networks from large, complex on-chip layouts. In this paper, we describe the techniques we use in a commercial static noise analysis tool to analyze crosstalk noise due to fully-coupled RLCK networks extracted from layout. Notable are the approaches we use to filter and lump aggressor couplings, as well as the techniques used to handle degeneracies in the modified nodel analysis (MNA) formulation. Furthermore, the nonmonotonicity of interconnect responses in the presence of inductance require additional "sensitizations" in searching the possible switching events inducing the worst-case noise. Comparisons with silicon indicate the need to include the substrate in the extracted models in certain cases.
Specificity of Retrograde Conduction in Screening for Atrioventricular Nodal Reentrant Tachycardia

UNLABELLED Baseline AV conduction properties (antegrade and retrograde) are often used to assess the presence of dual AV nodal physiology or concealed AV accessory pathways. Although retrograde conduction (RET) is assumed to be a prerequisite for AV nodal reentrant tachycardia (AVNRT), its prevalence during baseline measurements has not been evaluated. We reviewed all cases of AVNRT referred for radiofrequency ablation to determine the prevalence of RET at baseline evaluation and after isoproterenol infusion. RESULTS Seventy-three patients with AVNRT underwent full electrophysiological evaluation. Sixty-six patients had manifest RET and inducible AVNRT during baseline atrial and ventricular stimulation. Seven patients initially demonstrated complete RET block despite antegrade evidence of dual AV nodal physiology. In 3 of these 7 patients AVNRT was inducible at baseline despite the absence of RET. In the other four patients isoproterenol infusion was required for induction of AVNRT, however only 3 of these 4 patients developed RET. One of these remaining patients had persistent VA block after isoproterenol. CONCLUSIONS The induction of AVNRT in the absence of RET suggests that this is not an obligatory feature of this arrhythmia. Therefore, baseline AV conduction properties are unreliable in assessing the presence of AVNRT and isoproterenol infusions should be used routinely to expose RET and reentrant tachycardia.
Application of normal distribution in modeling global irradiation

The utility of the normal distribution curve in modeling hourly global radiation is presented and discussed. It is shown that nonzero hourly insolation values for each day can be represented by the variance of the normal distribution curve and total daily insolation. It is shown that using the normal distribution curve for representing hourly insolation values does not cause a significant loss of information content. The mean of the normal distribution curve is taken at solar noon. The variance of the normal curve is then calculated from the recorded data by matching the recorded value and the value obtained from the normal distribution curve at solar noon. This approach provides a simple and easy method for estimating hourly radiation and eliminates the need for large digital computers. It is shown that 24 hourly insolation values can be represented by four variables, namely, total daily insolation, variance of the normal distribution curve, and the times of sunrise and sunset. >
Model-based hazard analysis of undesirable environmental and components interaction

Identifying the detrimental effect of environmental factors and subsystem interactions are historically one of the most challenging aspects of early hazard assessment in the design of complex avionic systems. Therefore, a complete understanding of potential failure effects before and even after a catastrophe happens is a very difficult task. This paper proposes a model-based hazard analysis procedure for early identification of potential safety issues caused by unexpected environmental factors and subsystem interactions within a complex avionic system. The proposed methodology maps hazard and vulnerability modes to specific components in the system and analyzes the hazard propagation paths for risk control and protection strategies. The main advantage of the proposed method is the ability to provide the designers with means to use low-fidelity, high level models to identify hazardous interactions. Using this technique, designers can examine the collective impacts of environmental and subsystem risks on overall system during early stages of design and develop a hazard mitigation strategy.
Synthesizing any specified elastic behavior with a hybrid connection of simple compliant components

Achieving adequate force control is an important problem in the application of robotics technology to manufacturing tasks. One approach to this problem is the use of passive compliance. A number of methods have been proposed for designing a passive compliance mechanism with a prescribed spatial stiffness or compliance matrix using a parallel or serial connection of elastic devices. If the spatial stiffness or compliance matrix is isotropic, the constituent elastic devices are simple in the sense that they are strictly translational or rotational. Non-isotropic stiffness and compliance matrices require the use of elastic screw devices that couple translation and rotation. These screw devices are of a more complicated nature than the simple elastic devices that are sufficient for the isotropic case. In this article the authors demonstrate how these screw devices can be eliminated by using a hybrid connection of parallel and serial configurations consisting of only simple elastic devices. This method can be used to achieve any prescribed non-isotropic stiffness or compliance matrix.
Anti-Competitive Market Division Through Loyalty Discounts Without Buyer Commitment

We show that loyalty discounts without buyer commitment create an externality among buyers because each buyer who signs a loyalty discount contract softens competition and raises prices for all buyers. This externality can enable an incumbent to use loyalty discounts to effectively divide the market with its rival and raise prices. We prove that, provided the entrant's cost advantage is not too large, with enough buyers, this externality implies that in any equilibrium some buyers sign loyalty discount contracts, segmenting the market and reducing consumer welfare and total welfare. These propositions are true even if the buyers coordinate, the entrant is more efficient, the loyalty discounts cover less than half the market, and all the loyalty discounts are above cost. We also prove that these propositions hold even if we assume no economies of scale, no downstream competition, no buyer switching costs, no financial constraints, no limits on rival expandability, and no intraproduct bundle of contestable and incontestable
Pathophysiology of Neonatal Subconjunctival Hemorrhage

Of 111 newborns examined, 33 had subconjunctival hemorrhage (SCHN). Three of 19 patients delivered by cesarean section and 30 of 92 newborns delivered by the vaginal route had SCHN. Perinatal factors including duration of membrane rupture, length of second stage of labor, maternal weight and weight/length ratio, maternal ingestion of anti-inflammatory drugs, gravidity, birth weight, and Apgar score did not differ significantly in the groups with and without SCHN. It is proposed that in the majority of cases SCHN is a consequence of elevated venous pressure in the head and neck produced by compression of the fetal thorax and/or abdomen by uterine contractions. Tight umbilical cord around the neck probably represents an additional mechanism for SCHN.
The Role of Leptin in Regulating Neuroendocrine Function in Humans

Eating disorders are a group of disease states including anorexia nervosa, bulimia nervosa and binge eating on one end as well as episodic or chronic overeating resulting in obesity at the other end of the spectrum. These disorders are characterized by decreased and/or increased energy intake and are frequently associated with hormonal and metabolic disorders. The discovery of leptin, an adipocyte-secreted hormone acting in the brain to regulate energy homeostasis, and its subsequent study in human physiology have significantly advanced our understanding of normal human physiology and have provided new opportunities for understanding and possibly treating disease states, such as anorexia and bulimia nervosa. It has been recently discovered that leptin levels above a certain threshold are required to activate the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-thyroid axes in men, whereas the hypothalamic-pituitary-adrenal, renin-aldosterone, and growth hormone-IGF-1 axes may be largely independent of circulating leptin levels in humans. In this review, we summarize the latest findings related to the role of leptin in the regulation of several neuroendocrine axes, such as the hypothalamic-pituitary-gonadal and the hypothalamic-pituitary-thyroid axes in humans and discuss its potential pathophysiologic role in eating disorders.
Analytical form of frequency dependence of DGD in concatenated single-mode fiber systems

An analytical form for the lightwave angular frequency (/spl omega/) dependence of the squared value of the differential group delay in concatenated single-mode optical fiber systems is introduced. We show that the dependence can be described by a combination of cosine functions of rotation angles and their sums and differences of the fiber pieces, which are located between the two end pieces of the concatenated system. Using the analytical expression, the /spl omega/ dependence of real fiber systems can be simulated, providing information about the birefringence configuration of the system. Comparison with experimental data taken on real systems yields good qualitative agreement even if only few concatenations are considered.
Clinical Assessments of Parent-Child Interaction: Are Professionals Ready to Implement This Practice?.

This article discusses issues that are relevant to the clinical assessment of parent-child interaction in the context of early intervention and clinical infant services. Issues discussed include (a...
A Neuropsychological Comparison of Depressed Suicide Attempters and Nonattempters

The neuropsychological performance of 18 older inpatients with major depression who were admitted following a suicide attempt was compared with that of 29 older depressed inpatients who had never attempted suicide. There was an interactive effect of age and group on the Trail Making Test, part B, such that attempters showed greater performance declines with age. No other differences were detected between groups on a range of neuropsychological tasks. These findings are discussed in the context of the methodological limitations of previous studies and the need for future research to better elucidate the nature of the relationships between age, cognitive functioning, and suicidal behavior.
Migration Patterns and Environmental Effects on Stopover of Monarch Butterflies (Lepidoptera, Nymphalidae) at Peninsula Point, Michigan

Since 1996, the numbers of migrating monarch butterflies stopping over at Peninsula Point, Michigan, have been monitored by volunteers during the fall migration with standardized daily counts. In this study, we describe this project and examine: 1) general patterns of migration and stopover of monarchs at this site, and 2) how environmental conditions influence monarch stopover frequency. We tested for yearly, seasonal, and diurnal variation in monarch counts within each season. We further combined these data with basic weather information recorded at the time of each count to explore the effects of wind direction and speed, temperature, and cloud cover on monarch stopover abundance. A total of 22,539 monarchs was counted over 7 yr, with yearly totals ranging from 757 in 1998 to 6,638 in 1997. Over the 7-yr period, an average of 29 monarchs was recorded per count at Peninsula Point. Interestingly, in the migration season immediately following a major population decline at overwintering sites in Mexico, the total number of monarchs counted at Peninsula Point was not significantly different from long-term average counts. The timing of the peak of migration was not consistent from year to year, and there were few consistent temporal trends within seasons. More monarchs were counted with walking transects during the day than with a roost count in the early morning. Furthermore, more monarchs were counted earlier in the season than later. Of the environmental variables we examined, wind direction had a significant influence on the number of monarchs recorded on each count with higher counts during north winds. Cloud cover also influenced monarch counts, so that the number of monarchs observed increased with temperature and decreased with cloud cover. Based on the large numbers of monarchs that stop there each fall, we suggest that Peninsula Point represents an important monarch stopover site, and thus has the potential to increase our knowledge of monarch migration and stopover ecology greatly.