cssi/SciSciGPT-SciSciNet huggingface dataset:
Exercise-induced fibrinolytic activity and its effect on the degradation of fibrinogen, fibrin and fibrin-like precipitates

Abstract The heterogeneity of fibrinogen can be demonstrated in intact plasma by electrophoresis in low concentration of polyacrylamide gel. This quantitative technique was used to study the degradation of fibrinogen in blood by physiologically activated fibrinolysis following strenuous physical exercise. The results were compared with the lysis of fibrin and precipitated fibrinogen and fibrin monomer. Under conditions in which rapid fibrinolysis occurred, no degradation of fibrinogen into lower molecular weight derivatives could be demonstrated. The results are similar to those previously reported after the activation of fibrinolysis by venous occlusion. These findings suggest that significant intravascular fibrinogenolysis by plasmin under physiological conditions does not occur.
Some results on a partition of Z-matrices

Fiedler and Markham define an n × n matrix A to be an Lk-matrix if A has the form A = tI − B, where B is nonnegative and ϱk(B) ⩽ t < ϱk+1(B), k = 1,2,…, n. Here, ϱk(B) denotes the maximum spectral radius of all principal submatrices of B of order k for k = 1,2,…, n, and for completeness, ϱn+1(B) is defined to be +∞. Further, A is defined to be an L0-matrix if A = tI − B, where B is nonnegative and t < ϱ1(B). The classes L0 L1,…, Ln form a partition of the class of Z-matrices. In this paper, we characterize nonsingular matrices in these classes in terms of the principal minors of their inverses and extend this characterization to general Lk-matrices. Inverse Lk-matrices and Schur complements of Lk-matrices are also studied. An eigenvalue inequality involving Schur complements of Lk-matrices is obtained.
Molecular and Genetic Characterization of the Drosophila tartan Gene

Here we report the discovery and characterization of the Drosophila tartan gene. tartan is transcribed in an unusual embryonic pattern of intersecting stripes which are generated in response to the anterior-posterior and dorsal-ventral regulatory systems. tartan encodes a putative transmembrane protein containing extracellular leucine-rich repeats characteristic of numerous cell surface receptors and adhesion proteins. Its expression is correlated with aspects of segmentation and neurogenesis, including the formation of neuroblasts, sensory mother cells, and peripheral nerves. Mutants homozygous for a recessive lethal tartan loss-function allele exhibit defects in the position and number of cells within peripheral sense organs, the routing of peripheral nerves, and the organization of commissures within the central nervous system. Mutants are also defective in muscle organization. These results suggest that tartan is required for cell surface interactions important for normal organization of epidermal and subepidermal structures.
Molecular characteristics of glutamate receptors in the mammalian brain

The strong excitatory activity of L-glutamic acid on central nervous system neurons is thought to be produced by interaction of this amino acid with specific neuronal plasma membrane receptors. The binding of L-glutamate to these surface receptors brings about an increase in membrane permeability to Na+ and Ca2+ ions presumably through direct activation of ion channels linked to the membrane receptors. The studies described in this paper represent attempts to define the subcellular distribution and pharmacological properties of the recognition site for L-glutamic acid in brain neuronal preparations, to isolate and explore the molecular characteristics of the receptor recognition site, and, finally, to demonstrate the activation of Na+ channels in synaptic membranes following the interaction of glutamate with its receptors.
Contributing factors to information technology investment utilization in transition economies: An empirical investigation

Past research studies have identified multiple factors that affect the return on investments in information and communication technologies (ICT). We suggest that the efficiency of utilization of investments is also among the variables that can influence the level of returns and propose to investigate factors that can affect the efficiency of transformation of investments into macroeconomic outcomes. We conduct this research in the context of 18 transition economies (TE) and investigate how efficiently TEs utilize investments in telecoms to produce revenues, and what factors contribute to the efficiency of the investment utilization. We rely on a neoclassical framework of growth according and theory of complementarly to provide a theoretical foundation for our inquiry. This study employs a three-phase methodology utilizing data envelopment analysis, chister analysis, and decision trees to identify 15 factors that affect the efficiency of the utilization of investments in telecoms in the context of TEs. © 2008 Wiley Periodicals, Inc.
Graft replacement of the descending thoracic aorta: Results of “open” distal anastomosis

Abstract With the advent of rapid autotransfusion, we began to repair aneurysms of the descending thoracic and thoracoabdominal aorta by using an "open" technique, in which a single cross-damp is placed proximal to the aneurysm to exsanguinate the lower body. To determine whether open distal anastomosis effectively protects against spinal cord injury, we studied 71 consecutive patients (50 men, 21 women) who underwent this procedure beginning in April 1989. The patients ranged in age from 31 to 83 years (mean, 63.3 years). Most patients were hypertensive (n = 61; 86%) and symptomatic (n = 54; 76%). Most had been diagnosed with medial degeneration (n = 45; 63.4%) or aortic dissection (n = 16; 22.5%). Five patients (7.0%) were admitted with aortic rupture. We replaced the entire descending thoracic aorta in 31 (43.7%), the thoracoabdominal aorta in 21 (29.6%), and a segment of the descending thoracic aorta in 19 (26.7%). The average distal ischemic time was 22.4 minutes (range, 11 to 42 minutes). The amount of blood returned through the autotransfusion device averaged 2,099 mL. Eight patients (11.3%) died within 30 days (multiple organ failure, 3; hemorrhage, 2; coexisting ischemic heart disease, 3). Spinal cord dysfunction occurred in 6 patients (8.5%) (lower extremity paraparesis, 4; paraplegia, 2). Renal insufficiency requiring dialysis occurred in 4 patients (5.6%). We believe that the low incidence of spinal cord injury and renal insufficiency in this series may have resulted from the free, draining of the intercostal and lumbar arteries during aortic occlusion, which decreases cerebrospinal fluid and central venous pressures. With the lower body exsanguinated, we can also perform the distal anastomosis efficiently with a short ischemic time. Based on these favorable results, we conclude that the open technique is an excellent option for resection of these challenging thoracic aneurysms.
How public health impact is addressed: a retrospective view on three different oil spills

Spanning over a half century, over 38 “major” oil spill accidents have occurred, with the Deep Water Horizon disaster proving to be one of the largest oil spills on record. It is during these environmental disasters where the public community gathers together to participate in the clean-up effort and government entities coordinate various action plans. Whether it is using (1) workers to apply chemical dispersants to facilitate the remediation of oil in impacted areas or (2) volunteers to pick up “tar balls” from the beach shorelines; public health concerns during an oil spill are warranted for consideration. The purpose of this review was to illustrate a need for increase in scientific advancement and governmental focus on detecting and mitigating public health effects following an oil spill disaster. With focus on the Exxon Valdez, Prestige, and Gulf oil spills, the governmental and scientific community responses were assessed. Using the human-environmental system model, this review illustrates how the m...
The First Billion Years

The development of primordial inhomogeneities into the non-linear regime and the formation of the first astrophysical objects within low-mass (M ∼ 10 6 M ○. ) dark matter halos mark the end of the cosmic dark ages, about 150 Myr after the big bang. It is an early generation of extremely metal-poor stellar systems and accreting black holes in their nuclei that generated the ultraviolet/soft X-ray radiation and mechanical energy that reheated and reionized most of the hydrogen in the cosmos. The detailed thermal, ionization, and chemical enrichment history of the universe during the crucial formative stages around z = 10 - 30 depends on the power-spectrum of density fluctuations on small scales, on gas-phase H 2 astrochemistry, the stellar initial mass function and star formation efficiency, a complex network of poorly understood feedback mechanisms, and remains one of the crucial missing links in galaxy formation and evolution studies. In this talk I will review recent progress in understanding the epoch of first light, the impact of the earliest generation of luminous objects on later ones, and the hierarchical assembly of massive black holes from Population III seeds.
Mechanically insensitive afferents (MIAs) in cutaneous nerves of monkey

A problem in the study of nociceptors is that intense stimuli are used to locate the receptive field (RF), and thus the receptor may be damaged before the first responses are recorded. In addition, some nociceptors do not respond to the mechanical stimuli often used to search for the RF. To overcome these problems, an electrical search technique was developed to locate the RF of cutaneous nociceptors. In the hairy skin of anesthetized monkey, we used this technique to locate the RF of 63 A delta-fibers and 22 C-fibers that had extremely high thresholds or were unresponsive to mechanical stimuli. We refer to these afferents as mechanically insensitive afferents (MIAs). Ten A delta-fiber MIAs had a short latency response to stepped heat stimuli and could be responsible for first pain sensation. Five A delta-fiber MIAs and one C-fiber MIA did not respond to mechanical or heat stimuli but did respond to injection into the electrical RF of an artificial inflammatory soup containing histamine, bradykinin, prostaglandin E1, and serotonin. These chemoreceptors might be responsible for the pain and itch sensations that result from chemical stimuli. Some MIAs became more responsive to mechanical stimuli after injection into the RF of the inflammatory soup and, thus, may contribute to the hyperalgesia to mechanical stimuli associated with cutaneous injury. A large proportion of the A delta-fiber (48%) and C-fiber (30%) afferents in this study were insensitive to mechanical stimuli. The role of these MIAs in sensation needs to be studied further. The electrical search technique enables a systematic study of these afferents to be performed. This technique may also be of use to identify and characterize dorsal horn neurons that have inputs from MIAs.
Autoxidation of methyl linolenate and methyl linoleate: The effect of α‐tocopherol

α-Tocopherol substantially affects the distribution of peroxidic compounds formed during the autoxidation of methyl linolenate and methyl linoleate. In the autoxidation of both these unsaturated fatty acid esters the proportion of monohydroperoxides with conjugated double bonds in the trans, trans configuration is reduced until at high concentrations of α-tocopherol (5%) only cis, trans isomers are formed. In the autoxidation of methyl linolenate the proportion of hydroperoxy-epidioxides is reduced and only monohydroperoxides are formed when 5% α-tocopherol is present. The results are discussed in terms of recent findings concerning the mechanism of the autoxidation of unsaturated lipids.
A Physiological Comparison of Performance-Matched Female and Male Distance Runners

Abstract Eight male and eight female runners were matched on performance in a 24.2 km (15 mile) road race (X time ± SD = 115.1 ± 2.2 min for females, 115.8 ± 3.2 min for males). All subjects completed a graded treadmill run during which [Vdot]O 2 and heart rate (HR) were monitored at several submaximal running speeds and at maximal exercise. Blood samples, collected at rest and 3 min after maximal exercise, were analyzed for hematocrit and hemoglobin (Hb), lactic acid (LA) and 2,3-diphosphoglyceric acid (2,3-DPG) concentrations. Body composition was assessed via hydrostatic weighing. Group comparisons revealed that the males were taller, heavier, and higher in Hb than the females (p .05). 2,3-DPG was higher in the females when expressed relative to Hb (p < .05). These data i...
Influence of strain viability and antigen dose on the use of attenuated mutants of Salmonella as vaccine carriers

It is now accepted that oral killed typhoid vaccines are not effective at inducing protective anti-typhoid immunity. It is not known whether oral killed Salmonella can function as an effective carrier of other antigens to the immune system. In order to test this hypothesis, we immunized groups of mice with viable and non-viable preparations of aroA Salmonella dublin strain EL23 which codes for production of the binding subunit of the heat-labile enterotoxin of Escherichia coli (LT-B). Animals immunized orally with viable EL23 developed serum and mucosal anti-LT-B responses consistent with our previous findings. Significantly, mice immunized orally with ultraviolet-killed EL23 developed serum and mucosal antibody responses equivalent to those which developed in animals orally immunized with the same number of viable EL23. We extended these observations to include a number of methods of killing the organisms which may also preserve the ability of these strains to function as carriers. Our findings indicate that viability is not a requirement for use of a Salmonella strain as an immunological carrier. Moreover, our evidence indicates that bacteraemia and persistence in tissues are not necessary for oral priming, and therefore it may be best to dissociate the question of what makes the best live oral anti-typhoid vaccine from the question of what makes a good carrier of heterologous antigens.
Using State Lead Poisoning Surveillance System Data to Assess False Positive Results of Capillary Testing

Objective: The purpose of this study was to determine the false positive percentage of capillary blood lead screening in a statewide surveillance system and to explore potential predictors of false positive results. Methods: Data were all blood lead tests of 0–5 year old children in Maine during 2002–2003. We determined the proportion of children with elevated (≥10 μg/dL) capillary test results who received a venous confirmatory test, and calculated the percentage of false positive tests, defined as a capillary test of ≥10 μg/dL with a confirmatory venous test of <10 μg/dL. Multivariable binomial regression was used to determine whether capillary blood lead level and length of time between capillary and venous tests predicted false positive results, after controlling for potential confounders. We also examined the positive bias of the capillary test among both false positive and true positive results. Results: Seventy-three percent of elevated capillary screening tests (2.2 percent of all capillary screening tests) were false positives. False positive results were less likely for capillary levels of 15–19 μg/dL (RR=0.78; 95% CI 0.5–0.92) and 20 μg/dL or above (RR=0.83; 95% CI 0.71–0.96) compared to 10–14 μg/dL. The percentage of false positives did not vary by interval between screening and confirmatory tests. The capillary test exhibited a positive bias compared to the venous test, even among true positive results. Conclusions: False positive results may have been caused by sample contamination, rather than laboratory error or true variation in blood lead level between screening and confirmatory tests. Capillary screening could be improved by training in proper sample collection methods.
Precession of satellite orbits in general relativity — II

Experimental verification of the general theory of relativity by means of satellites is discussed. An improved set of orbits which maximize the astronomical «figure of merit» for pericenter precession is presented. A critique of the figure of merit shows that it is possible to further increase the observable effect.
Low-Temperature Thermoelectric Properties of Fe 2 VAl with Partial Cobalt Doping

Ternary metallic alloy Fe2VAl with a pseudogap in its energy band structure has received intensive scrutiny for potential thermoelectric applications. Due to the sharp change in the density of states profile near the Fermi level, interesting transport properties can be triggered to render possible enhancement in the overall thermoelectric performance. Previously, this full-Heusler-type alloy was partially doped with cobalt at the iron sites to produce a series of compounds with n-type conductivity. Their thermoelectric properties in the temperature range of 300 K to 850 K were reported. In this research, efforts were made to extend the investigation on (Fe1−xCox)2VAl to the low-temperature range. Alloy samples were prepared by arc-melting and annealing. Seebeck coefficient, electrical resistivity, and thermal conductivity measurements were performed from 80 K to room temperature. The effects of cobalt doping on the material’s electronic and thermal properties are discussed.
Inhibition of endocytosis by elevated internal calcium in a synaptic terminal.

DURING synaptic transmission in the nervous system, synaptic vesicles fuse with the plasma membrane of presynaptic terminals, releasing neurotransmitter by exocytosis1,2. The vesicle membrane is then retrieved by endocytosis and recycled into new transmitter-containing vesicles3–6. Exocytosis in synaptic terminals is calcium-dependent7–9, and we now report that endocytosis also is regulated by the intracellular calcium concentration ([Ca2+]i). Capacitance measurements10,11 in synaptic terminals of retinal bipolar neurons revealed that endocytosis was strongly inhibited by elevated [Ca2+]i in the range achieved by Ca2+-current activation. The rate of membrane retrieval was steeply dependent on [Ca2+]i, with a Hill coefficient of 4 and half-inhibition at ∼500 nM. At [Ca2+]i≥900 nM, endocytosis was entirely absent. The action of internal calcium on endocytosis represents a novel negative-feed-back mechanism controlling the rate of membrane recovery in synaptic terminals after neurotransmitter secretion. As membrane retrieval is the first step in vesicle recycling, this mechanism may contribute to activity-dependent synaptic depression.
Fluorinated coal as an internal standard for unit mass assignment

Fluorination of bituminous coal by elemental fluorine yields a solid product from which a solid distillate can be made by vacuum pyrolysis. Both fluorinated materials are easily made and are useful for mass spectrometric unit mass assignments. They have certain advantages over the commonly used perfluorokerosene, particularly for use in the high mass region.
Carotid Body Tumor A Case Report

Carotid body tumors are rare neoplasms, which typically present as a slow growing, painless neck mass found along the anterior border of the sternocleidomastoid muscle. These tumors are generally benign but possess aggressive local growth potential. Therefore, definitive treatment requires surgical resection. The authors describe a case of a patient with a carotid body tumor and review the most recent literature on this unusual topic.
Labile phosphate changes in ileum of the rat.

Summary1. Both muscularis and mucosa of rat show significant changes in amounts of energy-rich phosphate compounds when animal is fasted or fasted and briefly fed. 2. With increasing periods of starvation to 72 hours, the easily hydrolyzable phosphate compounds, Cr.P.-P. and A.T.P.P., diminish in both tissues in a predictable manner. 3. The mucosa appears to be more labile of the 2 tissues, although the muscularis shifts in the same direction and to nearly the same magnitude. 4. The assay of either Cr.P.-P. or A.T.P.P. on whole intestinal segments will provide sufficient data as would the independent assay of each, in the major tissues comprising the intestine, to follow the nature of the mechanism involved.
An isolable, metastable, geometrically unique manganese(IV) trihydrazide complex poised for reactivity

A metastable Mn(IV) tris(N,N′)diphenylhydrazide complex, Li2Mn(κ2-N2Ph2)3 (1) has been prepared, and characterized by X-ray diffraction analysis and spectroscopic techniques. Mn precursors are reacted with LiNHtBu to form an intermediate manganese-imido mixture, which reacts with N,N′-diphenylhydrazine, oxidizing the metal, and forming 1. Despite ease of formation, 1 is poised for reactivity, as loss of ether ligand triggers reductive elimination of azobenzene.
Delayed assessment and eager adoption of laparoscopic cholecystectomy: Implications for developing surgical technologies

Despite the prevailing emphasis in the medical literature on establishing evidence, many changes in the practice of surgery have not been achieved using proper evidence-based assessment. This paper examines the adoption of laparoscopic cholecystectomy (LC) into regular use for the treatment of cholecystitis and the process of its acceptance, focusing on the limited role of technology assessment in its appraisal. A review of the published medical literature concerning LC was performed. Approximately 3000 studies of LC have been conducted since 1985, and there have been nearly 8500 publications to date. As LC was adopted enthusiastically into practice, the results of outcome studies generally showed that it compared favorably with the traditional, open cholecystectomy with regard to mortality, complications, and length of hospital stay. However, despite the rapid general agreement on surgical technique, efficacy, and appropriateness, there remained lingering doubts about safety, outcomes, and cost of the procedure that suggested that essential research questions were ignored even as the procedure became standard. Using LC as a case study, there are important lessons to be learned about the need for important guidelines for surgical innovation and the adoption of minimally invasive surgical techniques into current clinical and surgical practice. We highlight one recent example, natural orifice transluminal endoscopic surgery and how necessary it is to properly evaluate this new technology before it is accepted as a safe and effective surgical option.
A precise upper limit for the correctness of the Navier-Stokes theory with respect to the kinetic theory

The condition of positive normal pressures must hold for all solutions in the kinetic theory, but is violated by the Navier-Stokes equations for sufficiently high distortions. A dimensionless measure of this discrepancy is furnished by the tension number. In order for all pressures to be positive, it is necessary and sufficient that the tension number be less than 1. If this condition is violated, the normal-stress effects of the kinetic and Navier-Stokes theories are of opposite sign.
Chemiluminescent standards for quantitive comparison of two‐dimensional electrophoresis western blots

Chemiluminescent probes offer highly sensitive quantitative analyses of proteins blotted from electrophoretic gels onto a supporting matrix (e.g. nitrocellulose or polyvinylidene difluoride). Visualization of signals from probes involves the emission of light that is dependent on a number of variables (e.g. conjugated enzyme activity, antibody titer, hybridization efficiency, substrate concentration, chemical reactivity, temperature, etc.). Thus, it is important to be able to correct for these variations. For example, the exposure time of the blot to the detection medium (e.g., film or digital camera) is a critical variable in the final results. Several protein samples separated on a single blot (e.g. one-dimensional resolution) can be compared from the ratio of the individual proteins, but comparison of separate blots completed on different days requires a chemiluminescent standard. The situation is more complex when only one sample per gel/blot is used (i.e. two-dimensional electrophoresis (2-DE)). This paper describes a method for preparing agarose embedded standardized strips that contain dilutions of antigens that can be visualized with the corresponding probe antibody. This standardization strip can be produced from common laboratory supplies and provides a method to correct for alterations in chemiluminescent intensities from different 2-DE analysis. Several standardization strips can be produced simultaneously and then used during the electroblotting step of different blots on different days.
Free subunits of ribulose-1,5-bisphosphate carboxylase in pea leaves☆

Abstract Pea leaves, supplied with [ 35 S]methionine, were homogenized and a crude hypotonic soluble fraction was centrifuged on sucrose gradients to separate fully assembled ribulose-1,5-biphosphate (RuBP) carboxylase from any free or partially assembled carboxylase subunits. Slowly sedimenting subunits of the enzyme were identified in upper fractions of the sucrose gradient, using polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS), isoelectric focussing, and immune precipitation. The presence of these subunits in low molecular weight form was shown not to be due to artefactual dissociation of the enzyme. It is suggested that these subunits are related to the assembly of RuBP carboxylase.
Hydrogen Bonding in Human Manganese Superoxide Dismutase Containing 3-Fluorotyrosine

Incorporation of 3-fluorotyrosine and site-specific mutagenesis has been utilized with Fourier transform infrared (FTIR) spectroscopy and x-ray crystallography to elucidate active-site structure and the role of an active-site residue Tyr34 in human manganese superoxide dismutase (MnSOD). Calculated harmonic frequencies at the B3LYP/6-31G** level of theory for L-tyrosine and its 3-fluorine substituted analog are compared to experimental frequencies for vibrational mode assignments. Each of the nine tyrosine residues in each of the four subunits of the homotetramer of human MnSOD was replaced with 3-fluorotyrosine. The crystal structures of the unfluorinated and fluorinated wild-type MnSOD are nearly superimposable with the root mean-square deviation for 198 α-carbon atoms at 0.3 A. The FTIR data show distinct vibrational modes arising from 3-fluorotyrosine in MnSOD. Comparison of spectra for wild-type and Y34F MnSOD showed that the phenolic hydroxyl of Tyr34 is hydrogen bonded, acting as a proton donor in the active site. Comparison with crystal structures demonstrates that the hydroxyl of Tyr34 is a hydrogen bond donor to an adjacent water molecule; this confirms the participation of Tyr34 in a network of residues and water molecules that extends from the active site to the adjacent subunit.
Protein kinase C mediates insulin-inhibited Ca2+ transport and contraction of vascular smooth muscle.

Abstract Insulin acutely inhibits contraction of primary cultured vascular smooth muscle (VSM) cells from canine femoral artery by inhibiting contractile agonist-induced Ca 2 + influx. Insulin also inhibits contraction at step(s) distal to intracellular Ca 2 + concentration (Ca 2 + i ) by stimulating cyclic guanosine monophosphate (GMP) production. We wished to see whether these effects of insulin are mediated by protein kinase C (PKC). Ca 2 + influx was assessed by measuring the rate of fluorescence quenching of intracellular fura 2 by extracellular Mn 2 + . We found that 10 μmol/L serotonin (5-HT) stimulated Mn 2 + influx 3-fold, and 1 nmol/L insulin inhibited the 5-HT–stimulated component of Mn 2 + influx by 63% ( P .05), but insulin had no effect in the presence of 1 μmol/L staurosporine, an inhibitor of PKC. In the absence of insulin, preincubating cells with 0.1 μmol/L phorbol 12-myristate 13-acetate (PMA) for 5 min inhibited the 5-HT–stimulated component of Mn 2 + influx by 69% ( P .05). Insulin inhibited cell contraction induced by raising Ca 2 + i to supraphysiologic levels with ionomycin by 75% ( P .05). We also noted that 10 − 6 mol/L calphostin C, another PKC inhibitor, or 16-h preincubation with PMA completely blocked this effect of insulin. Finally, 10-min exposure to insulin or PMA increased cyclic GMP production in ionomycin-treated cells by 50% and 64%, respectively (both P .05). We conclude that insulin inhibits VSM cell contraction by inhibiting 5-HT–stimulated Ca 2 + influx and also at step(s) distal to Ca 2 + i by a PKC-dependent mechanism.
Grooves Effect on Lift: Data Correlation and Prediction for Kinetic Energy Projectiles

Effect of grooves on the normal force of an antiarmor long rod kinetic energy (KE) projectile is analyzed and numerically quantified. The effect was studied for body-alone and body with fins where clear and distinct effects were experimentally observed for each. Wind tunnel data sets were analyzed and an algebraic, semi-empirical correlations were constructed utilizing the main physical parameters of the projectile body and fins, as well as the flow parameters. The correlations provide a simple method to estimate the increase or decrease in the vehicle total normal force due to grooves, and can be implemented in fast aerodynamics design codes. One separate set of data was dedicated for independent validation, and the correlation predicted the effect well, both in magnitude and sign. The present correlation is the only one known for predicting the lift loss (or gain) due to grooves. In addition, a better understanding of the contributions of grooves to both body-alone and fins-in-presence- of-body, is presented. The correlation is constructed for the Mach number range of 2.0 < M < 5.5 and small angles of attack < 6 deg, which cover the flight envelope of tactical KE antiarmor projectiles. The established correlations provide direct incremental corrections over smooth-bodv values.
Determinants of vascular dementia in the Cardiovascular Health Cognition Study.

Objective: The authors evaluated 3,375 participants without dementia at the time of MRI in 1991 to 1994 over 5.7 years for incident dementia and type of dementia. Methods: Incidence of and risk factors for vascular dementia (VaD) were measured using both pre-MRI and modified State of California Alzheimer9s Disease Diagnostic and Treatment Centers (ADDTC) post-MRI review and further classified Alzheimer disease (AD) by the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer9s Disease and Related Disorders Association (NINCDS-ADRDA) criteria. Results: Approximately 44% (213) of 480 incident dementia cases were classified as possible or probable VaD by ADDTC. The incidence of VaD increased with age and was greater in blacks than whites. Risk factors for VaD included age, Modified Mini-Mental State Examination, high white matter grade, number of MRI infarcts, ventricular size, and history of stroke. Conclusions: Vascular disease in the brain is prevalent among incident dementia cases. There is a substantial overlap between cases classified as Alzheimer disease by Neurological and Communicative Disorders and Stroke and the Alzheimer9s Disease and Related Disorders Association and vascular dementia (VaD) by modified State of California Alzheimer9s Disease Diagnostic and Treatment Centers criteria. The substantial contribution of vascular disease would be missed without inclusion of MRI. Treatment of risk factors for VaD could have an important impact on incidence of dementia.
Barrier-limited transport in semiconductor devices

Current transport over a simple parabolic barrier is studied using the diffusion theory (dissipative transport) and the kinetic theory (ballistic transport). The solution of the diffusion equation for the barrier-limited case shows that the current density is inversely proportional to the width of the barrier. The solution of the kinetic theory, described by Euler's equation of classical fluid mechanics, gives a current density that is independent of the width of the energy barrier, and which is equal to 1.52 times the current density obtained from the thermionic emission theory. Euler's equation and the diffusion equation may be naturally combined into a single transport equation, and the current density derived from this equation shows the effects of both the ballistic and dissipative limits. The ballistic limits are of significance for the operation of the permeable base transistor and similar devices.
Further observations on the nature of the house dust antigen

Abstract 1. 1. A linters extract is described with which immunologically specific endermal reactions may be obtained in dust-sensitive patients. 2. 2. It is not irritating to normal skins when used in a dilution which is satisfactory for detecting sensitivity. 3. 3. Guinea pigs can be sensitized and shocked with this linters extract. 4. 4. The active principle in this extract cannot be cottonseed or any of the contaminants ordinarily present in house dust extracts prepared from vacuum-cleaner dusts.
Temperature-Dependent Autoxidation of Conjugated Trienols from Apple Peel Yields 6-Methyl-5-hepten-2-one, a Volatile Implicated in Induction of Scald

Conjugated triene (CT) oxidation products of alpha-farnesene have long been thought to be involved in development of superficial scald in apple fruit. Early studies found that CT hydroperoxides and the volatile 6-methyl-5-hepten-2-one (MHO) are major in vitro autoxidation products of alpha-farnesene. However, it was recently shown that > or =99% of the oxidation products of alpha-farnesene that accumulate in apple peel are conjugated trienols (CTols), isomers of 2,6,10-trimethyldodeca-2,7,9,11-tetraene-6-ol. HPLC-purified CTols from fruit of two scald-susceptible cultivars, Granny Smith (GS) and Red Delicious (RD), were used to study autoxidation of these compounds in vitro. Incubation of CTols in sealed glass vials under air resulted in accumulation of MHO. Oxygen enrichment did not increase the amount of MHO produced. Regardless of which cultivar CTols were derived from, at 0 degrees C autoxidation yielding MHO was quite slow and linear, whereas at 20 degrees C MHO production was much more rapid, and after several hours the rate increased abruptly. However, CTols isolated from GS and RD fruit differed in the duration of the initial lag phase and the overall level of MHO generated at 20 degrees C. The sharp increase in MHO production occurred after 3 h with GS CTols and at about 12 h with RD CTols. Also, the yield of MHO from GS CTols after 6 h at 20 degrees C was nearly 6-fold greater than that from RD CTols after 20 h at 20 degrees C. The antioxidants butylated hydroxytoluene and diphenyamine reduced the yield of MHO by about 97%. Recent work has shown that MHO can induce scald-like symptoms in apple peel and that tissue sensitivity increases with time in storage. This may explain the correlation between high CTol levels and scald development, and why symptoms rapidly intensify when fruits are removed from cold storage.
Increase in micronucleated erythrocytes associated with babesiosis in Syrian golden hamsters

The effect of infection by Babesia microti, a tick-borne piroplasm endemic to the northeastern United States, on the temporal pattern of micronucleated erythrocyte frequencies in peripheral blood was investigated in male Syrian golden hamsters. Significantly greater frequencies of micronucleated erythrocytes occurred in the blood of infected hamsters from 26 to 46 days after injection with B. microti, the magnitude of which within individual hamsters correlated highly with the percentage of polychromatic erythrocytes and the extent of parasitization. These data suggest that parasitic infection and other factors which alter the rate of erythropoiesis should be considered when the micronucleus assay is used in environmental or laboratory studies of genetic toxicity.
Intraguild predation: The dynamics of complex trophic interactions.

There is a long-standing debate in ecology concerning the relative importance of competition and predation in determining community structure. Recently, a novel twist has been added with the growing recognition that potentially competing species are often engaged in predator-prey interactions. This blend of competition and predation is called intraguild predation (IGP). The study of IGP will lead to a reconsideration of many classical topics, such as niche shifts, species exclusion and cascading interactions in food webs. Theoretical models suggest that a variety of alternative stable states are likely in IGP systems, and that intermediate predators should tend to be superior in exploitative competition. Many field studies support these expectations. IGP is also important in applied ecological problems, such as the conservation of endangered species and fisheries management.
Phosphodiesterase 4 inhibitors enhance sexual pleasure-seeking activity in rodents.

Pleasure-seeking deficits, including lack of libido, are a core feature of depression. Animal and preliminary clinical studies both suggest that phosphodiesterase 4 (PDE4) is a target for developing novel antidepressants. This study examined the potential involvement of PDE4 in the pathology of depression in both animal models and human postmortem brains. In humans, PDE4B and PDE4D levels were elevated in cingulate cortical tissue from individuals with major depressive disorder (MDD) compared to controls. Using the female urine smelling test (FUST), a recently refined method for monitoring sexual pleasure-seeking activity in mice, we found that icv infusion of selective potent PDE4 inhibitors enhanced sexual pleasure-seeking activity in male mice that underwent the learned helplessness or serotonin depletion paradigms. The infusion also increased sexual pleasure-seeking activity in naive male mice. The results suggest that PDE4 may be a plausible contributor to the sexual pleasure-seeking deficits seen in depressed patients; inhibiting PDE4 may restore these deficits.
Borinium Adduct Ion Formation with Barbiturates in a Quadrupole Ion-trap Mass Spectrometer

Barbiturates are a class of drugs that are utilized as anesthetics and sleeping agents and are used for the treatment of anxiety, epilepsy and other psychiatric disorders. Because of their pyrimidine structures, barbiturates are highly basic compounds. The evaluation of the formation of adducts involving the borinium ion, B(OCH 3 ) 2 + , and the barbiturates in a quadrupole ion trap is described. The adducts [M + 73] + dissociate by elimination of methanol followed by the attachment of a trimethylborate or water molecule. This multi-step pathway is characteristic of a basic, nitrogen-containing structure that has at least one acidic hydrogen. Model compounds were used to probe the nature of this unusual reaction pathway, which involves nucleophilic attack by a methoxyl oxygen of neutral trimethyl borate at the boron atom of the adduct.
Luteal insufficiency: Correlation between endometrial dating and integrated progesterone output in clomiphene citrate-induced cycles

Abstract Midluteal phase endometrium was histologically dated with midcycle luteinizing hormone surge time in 29 cycles from 10 parous women during untreated cycles (control) and treatment with clomiphene citrate 50 mg and 150 mg daily on days 5 through 9. Integrated progesterone output for 7 days after luteinizing hormone surge calculated from the daily plasma progesterone levels was 66.6 ± 9.8 ng/ml in the control group compared with 117.5 ± 18.6 ng/ml for clomiphene citrate 50 mg treatment and 152.1 ± 11 ng/ml for clomiphene citrate 150 mg treatment (p
Positive Control of Transcription by a Bacteriophage Sigma Factor

A sigma specificity factor induced by infection with bacteriophage T4 directs the in vitro synthesis of RNA species corresponding to those switched on in vivo about 2 min after infection.
Antioxidant treatment with phenyl-α-tert-butyl nitrone (PBN) improves the cognitive performance and survival of aging rats

Abstract Accumulating evidence has implicated free radical production and resultant oxidative damage as a major contributing factor in brain aging and cognitive decline. In the present study, aging 24-month-old rats were chronically treated with the synthetic spin-trapping antioxidant phenyl-α- tert -butyl nitrone (PBN) for up to 9.5 months. Chronic PBN treatment (1) improved the cognitive performance of aged rats in several tasks, (2) resulted in greater survival during the treatment period, and (3) decreased oxidative damage within brain areas important for cognitive function. These results not only provide a direct linkage between free radicals/oxidative damage and cognitive performance in old age, but also suggest that synthetic brain antioxidants could be developed to treat or prevent agea-associated cognitive impairment and Alzheimer's disease.
Principles of exercise prescription for patients with chronic heart failure

Chronic heart failure (CHF) is a common and debilitating condition characterized by reduced exercise tolerance. While exercise training was once thought to be contraindicated for patients with CHF, a substantial body of data has been published over the last two decades to support the use of exercise programs for these patients. Improvements in exercise capacity, quality of life, and mortality have been demonstrated among patients with CHF who have participated in formal exercise programs. Exercise prescription is a means of assessing and interpreting clinical information and applying the principles of training to develop an appropriate regimen so that these benefits are achieved. The major principles of the exercise prescription are the mode, frequency, duration, and intensity. Importantly, safe and effective exercise prescription for patients with CHF requires more than the application of these principles; it also requires careful consideration of the individual patients' functional status, comorbid conditions, medications, contraindications, and personal goals and preferences. Recent studies have demonstrated that a wide spectrum of patients with CHF benefit from appropriately applied exercise training, including those with both systolic and diastolic dysfunction, atrial fibrillation, pacemakers, implantable cardioversion devices, and post-cardiac transplantation. Increasingly, the principles of exercise prescription are included as a component of comprehensive CHF management programs. Evidence has accumulated that CHF patients who participate in rehabilitation programs have better health outcomes in terms of reduced morbidity and mortality, as well as lower hospitalization rates and lower overall health care costs.
Respiratory arrest following posteriorly displaced odontoid fractures. Case reports and review of the literature

Posterior displacement of the odontoid after fracture occurs much less frequently than does anterior displacement. Experience with four patients suggests that anatomic reduction may not be possible and prolonged attempts to gain reduction are not advisable. Those cases should be managed with early application of a halo vest. A rotating frame should be avoided. The potential for respiratory arrest, at least in the older individual, is great and can be precipitated even by a change of position in the process of turning on the rotating frame. The mechanism of the respiratory failure is obscure.
Modification of kainate-induced behavioral and electrographic seizures following inhibition of nitric oxide synthase in mice.

Abstract We assessed the effects of Nω-nitro- l -arginine-methyl ester (L-NAME), an inhibitor of nitric oxide synthase (NOS), on behavioral and electrographic seizures elicited in mice by convulsant doses of kainate. In Expt. 1, L-NAME dose-dependently potentiated the convulsant effects of kainate (44 mg/kg s.c.) transforming long-latency clonic convulsions into short-latency fits of wild-running, and increased the incidence of kainate-induced mortality. The proconvulsant effects of L-NAME (5 mg/kg i.p.) did not reflect shortened latency to kainate-induced epileptiform afterdischarge recorded via electrodes chronically implanted into the hippocampus, amygdala, frontal cortex or mesencephalic reticular formation (Expt. 2). We also observed a dramatic uncoupling of behavioral and electrographic seizures in mice treated with L-NAME 30 min prior to kainate: 4 6 mice treated with L-NAME failed to express afterdischarge from any of the sites assessed during fits of wild-running. The proconvulsant effects of L-NAME were dependent on the route of administration of kainate, as the inhibitor of NOS failed to alter behavioral (clonic) or electrographic seizures elicited by intrahippocampal kainate (1 nmol, Expt. 3) yet shortened latency to fits of wild-running following i.c.v. kainate (1 nmol, Expt. 4) and reduced the dose of systemic kainate required for either clonic convulsions or wild-running (Expt. 5). The observations that L-NAME potentiates kainate-induced wild-running but not necessarily clonus suggest the involvement of tectopontine mechanisms.
Genetic Transformation of Streptococcus sanguis (Challis) with Cryptic Plasmids from Streptococcus ferus

By using the basic methodology initially published by Kretschmer et al. (J. Bacteriol. 124:225-231, 1975), we have been able to introduce phenotypically cryptic plasmids from Streptococcus ferus (formerly Streptococcus mutans subsp. ferus) into Streptococcus sanguis by genetic transformation. In this system, the entry of the cryptic plasmids is selected indirectly. This is effected with transforming deoxyribonucleic acid mixtures in which the cryptic plasmid deoxyribonucleic acid is present in an approximate 10-fold molar excess with respect to a plasmid (pVA1) known to confer erythromycin resistance. Under such conditions, 5 to 10% of the pVA1-containing erythromycin-resistant transformants were cotransformed with cryptic plasmid deoxyribonucleic acid. pVA1 may be selectively eliminated by growth of its S. sanguis host strain at 42 degrees C, enabling the construction of isogenic strains with and without S. ferus cryptic plasmids. Comparative physiological studies of such strains have failed to reveal any plasmid-conferred phenotypes in S. sanguis. With this procedure, we have been able to physically separate two small cryptic plasmids (2.4 x 10(6) and 2.8 x 10(6) daltons) of S. ferus. Although these plasmids were found naturally to exist in a single S. ferus host, they were able to replicate independently of one another in S. sanguis. Restriction enzyme fingerprinting indicated that these plasmids did not share a common ancestry.
“Unsteady Gait”: An Uncommon Presentation and Course of Malignant Melanoma in Terminal Ileum—A Case Report and Review of Literature

Malignant melanoma within the gastrointestinal tract is an uncommon neoplasm that is usually metastatic in origin, with primary melanomas being relatively uncommon. Embryologically melanocytes normally exist in the esophagus, stomach, small bowel, and anorectum and this theory supports the primary melanoma of the gastrointestinal tract that has been confirmed for lesions occurring through several published reports. However, most patients with brain metastases from malignant melanoma are diagnosed after treatment for known extracranial metastases and have poor outcomes. Our case is unique in that we discuss an unusual case of 69-year-old female patient presented with unsteady gait as the first symptom of disease and where the presumed primary lesion later was found in the terminal ileum on colonoscopy. Treatment consisted of surgical removal of the terminal ileal lesion with chemotherapy, whole-brain radiotherapy, and cyberknife radiosurgical procedure. Patient was in remission for more than 14 months and later succumbed to disease. Despite the advances in therapeutic options, prognosis for patients with melanoma brain metastases remains poor with a median survival time of six months after diagnosis.
Variability of cardiac output in dogs under chloralose and urethane anesthesia

Abstract Cardiac output was determined in nine mongrel dogs 2 and 3 hours after induction of anesthesia with urethane, 750 mg/kg, and chloralose, 75 mg/kg. Cardiac output at 3 hours declined significantly from 2-hour postanesthetic values. The only other significant hemodynamic change was an increased pulmonary resistance. When chloralose and urethane anesthesia are employed in animal experimentation, sequential hemodynamic changes should be appreciated to avoid serious experimental error.