cssi/SciSciGPT-SciSciNet huggingface dataset:
Free radicals and lipid peroxidation mediated injury in burn trauma: the role of antioxidant therapy

Burn trauma produces significant fluid shifts that, in turn, reduce cardiac output and tissue perfusion. Treatment approaches to major burn injury include administration of crystalloid solutions to correct hypovolemia and to restore peripheral perfusion. While this aggressive postburn volume replacement increases oxygen delivery to previously ischemic tissue, this restoration of oxygen delivery is thought to initiate a series of deleterious events that exacerbate ischemia-related tissue injury. While persistent hypoperfusion after burn trauma would produce cell death, volume resuscitation may exacerbate the tissue injury that occurred during low flow state. It is clear that after burn trauma, tissue adenosine triphosphate (ATP) levels gradually fall, and increased adenosine monophosphate (AMP) is converted to hypoxanthine, providing substrate for xanthine oxidase. These complicated reactions produce hydrogen peroxide and superoxide, clearly recognized deleterious free radicals. In addition to xanthine oxidase related free radical generation in burn trauma, adherent-activated neutrophils produce additional free radicals. Enhanced free radical production is paralleled by impaired antioxidant mechanisms; as indicated by burn-related decreases in superoxide dismutase, catalase, glutathione, alpha tocopherol, and ascorbic acid levels. Burn related upregulation of inducible nitric oxide synthase (iNOS) may produce peripheral vasodilatation, upregulate the transcription factor nuclear factor kappa B (NF-kB), and promote transcription and translation of numerous inflammatory cytokines. NO may also interact with the superoxide radical to yield peroxynitrite, a highly reactive mediator of tissue injury. Free radical mediated cell injury has been supported by postburn increases in systemic and tissue levels of lipid peroxidation products such as conjugated dienes, thiobarbituric acid reaction products, or malondialdehyde (MDA) levels. Antioxidant therapy in burn therapy (ascorbic acid, glutathione, N -acetyl-L-cysteine, or vitamins A, E, and C alone or in combination) have been shown to reduce burn and burn/sepsis mediated mortality, to attenuate changes in cellular energetics, to protect microvascular circulation, reduce tissue lipid peroxidation, improve cardiac output, and to reduce the volume of required fluid resuscitation. Antioxidant vitamin therapy with fluid resuscitation has also been shown to prevent burn related cardiac NF-kB nuclear migration, to inhibit cardiomyocyte secretion of TNF-a, IL-1b, and IL-6, and to improve cardiac contractile function. These data collectively support the hypothesis that cellular oxidative stress is a critical step in burn-mediated injury, and suggest that antioxidant strategies designed to either inhibit free radical formation or to scavage free radicals may provide organ protection in patients with burn injury. # 2003 Elsevier Science Ireland Ltd. All rights reserved.
Writing the Arab-Israeli Conflict: Pragmatism and Historical Inquiry

Writing the Arab-Israeli Conflict: Pragmatism and Historical Inquiry. By Jonathan B. Isacoff. Lanham, MD: Lexington Books, 2006. 216p. $70.00 cloth, $24.95 paper. Jonathan Isacoff argues that American political scientists, and in particular international relations researchers, should be much more self-critical about their historiography. Political science, he claims, is afflicted by a stubborn “positivism” that leads case-study, qualitative researchers (like Kenneth Waltz) and large-n, quantitative researchers (like J. David Singer) alike to treat historical data as if they are value-free and unchanging. This historiography blinds researchers to the normative and theoretical biases of their theories—especially a bias toward system-structural explanations for international conflict—by screening out data that contradict those theories. Moreover, subsequent revisions to the historical record undermine their findings, leaving research that is empirically disengaged and irrelevant to political experience.
Antigen-Binding Activity of 6S Subunits of β2-Macroglobulin Antibody

Direct evidence is provided for the antigen binding activity of the 6S subunits formed by reduction and alkylation of rabbit beta2-macroglobulin antibody. Binding activity of the subunits was clearly demonstrated by radioimmunoelectrophoresis with a preparation of purified rabbit antibody against the p-azobenzenearsonate group, which contained 40 percent of beta2M-antibody. The precipitate arc formed between the subunits and sheep antiserum against rabbit macroglobulin was shown to bind radioactive antigen specifically.
Measuring the flux and sinking speed of marine snow aggregates

Abstract The flux and concentration of large amorphous aggregates (marine snow) were measured using a combination camera and sediment trap deployed at 380 m (390 m water depth) in the Panama Basin in April 1985. Results at this site indicate that essentially all settling particles arrive at the sea floor as components of large aggregates, with insignificant contributions of solitary fecal pellets. The observed flux of any particle divided by its concentration gives an estimate of a model parameter which can be interpreted as particle settling speed. Application of this method to marine snow indicates that, on average, larger aggregates (4–5 mm) settle more slowly (1 m day−1) than smaller aggregates (1–2.5 mm, 36 m day-1). These sinking speed estimates represent the average sinking speed of all aggregates photographed in the water column at the depth of the sediment trap. As such, these numbers may reflect the relative abundances of fast and slow-sinking aggregates rather than the absolute sinking speed of material entering the trap. Particles were observed to change positions or disappear between photographs, indicating water movement which may have been associated with the activity of grazing organisms within the sediment trap.
Cholinergic excitation of mammalian hippocampal pyramidal cells

Abstract Responses of CA1 pyramidal neurons to ACh were recorded with intracellular microelectrodes utilizing the in vitro guinea pig hippocampal slice preparation. ACh was delivered by drop or iontophoretic application to stratum oriens or stratum radiatum. Threshold dose for drop application was 1 mM. An initial hyperpolarization of 3.1 ± 1.8 (S.D.) mV associated with a decrease in membrane input resistance (RN) of 21 ± 9% (S.D.) occurred in about half the cells. This result is consistent with a presynaptic action of ACh mediated through excitation of inhibitory interneurons. This interpretation was supported by recordings of cholinergic excitatory responses from presumed interneurons, and repetitive spontaneous IPSPs from pyramidal neurons during the hyperpolarization. ACh evoked a slow depolarization (14.3 ± 10.8 (S.D.) mV) accompanied by a peak increase in apparent input resistance (Ra) of about 60% in the majority of cells. Large increases in spike frequency were associated with these events but action potential shape was unchaged. Plots of Ra versus membrane potential following ACh application revealed that Ra increases were proportionately higher at depolarized membrane potential levels (⩽ − 70 mV) in some neurons. In these cells Ra was significantly at −60 mV (28%), but only 6% at −75 mV. These results are consistent with the conclusion that ACh reduces a voltage-dependent gK, distinct from delayed rectification. ACh also induced a non-voltage-dependent increase in Ra in some cells. ACh-evoked changes in Ra were long-lasting and gave rise to alterations in firing mode, with development of burst generation. ACh also transiently blocked afterhyperpolarizations which followed spike trains in pyramidal neurons and presumed interneurons, an action which may be related to effects on a Ca2+-activated gK.
Patient weight counseling choices and outcomes following a primary care and community collaborative intervention.

Abstract Objective Obesity has become a public health epidemic in adults and children. Clinician practices need new models to effectively address overweight in patients, yet, practices lack time and resources. We tested a clinician-delivered intervention that utilized community resources for in-depth counseling for unhealthy behaviors including overweight. Methods Eligible patients in nine primary care practices were identified using an electronic linkage system (eLinkS) which also automated patient referrals to group (Weight Watcher's), telephone counseling (TC), or usual care. Pre/post-survey data were used to assess factors related to counseling choices as well as changes in BMI (kg/m 2 ) and weight-related behaviors using descriptive statistics, unadjusted, and adjusted statistical analyses. Results Study sample ( n = 146) was 70% female with a mean age of 57 years. More patients (57%) selected WW, followed by usual care (27%) or TC (16%). Age, gender, clinician recommendation, and counseling program characteristics were influential in counseling selections. Weight Watcher's participants and those in TC, reported statistically significant weight loss, WW participants also reported significant increases in fruit/vegetable intake; after 4 months compared with usual care. Conclusions This practice-based intervention utilizing community counseling referrals was associated with positive health behavior change. Practice Implications Identifying influential factors related to patient weight counseling choices may help guide referrals to community programs.
ULTRASTRUCTURE OF STEWARTIOTHECA (MEDULLOSACEAE) PREPOLLEN

Ultrastructure of prepollen from the medullosan seed fern Stewartiotheca warrenae Eggert and Rothwell has been studied with the scanning electron microscope. Nitrocellulose ("liquid" type) peel preparations of pollen organ sections were placed on millipore filters and the grain fragments were extracted by rinsing the peels with acetone. Prepollen is of the Monoletes-type and is elliptical in polar view, averaging 264 ,um long and 183 ,um wide. Individual grains possess two deep, crescent-shaped grooves on the distal surface and a monolete suture with a median deflection proximally. The exine is constructed of a thick (1-2 ,um), homogeneous nexine layer overlain by a sexine that is characterized by interconnecting spheroidal chambers. Chamber diameter decreases only slightly from the exterior of the sexine, inward, but the frequency and degree of interconnection among the chambers increases noticeably toward the interior of the wall layer. With regard to this latter feature the prepollen of Stewartiotheca appears intermediate between the organizations known for other Monoletes grains. The grains of Stewartiotheca compare most closely with those of Dolerotheca and Sullitheca.
952-26 Myogenic Responses and Intrinsic Tone of Coronary Arterioles are Altered by Cardiopulmonary Bypass and Cardioplegia

Cardiopulmonary bypass (CPB) and cardioplegia are associated with systemic hypotension and altered vascular responses. Myogenic properties and intrinsic tone of vascular smooth muscle are important mechanisms in the regulation of coronary blood flow and systemic vascular resistance. To examine if CPB and cardioplegic arrest alter myogenic reactivity and the intrinsic tone in the coronary microcirculation, pigs were placed on CPB. Selected hearts (n = 6) were arrested with a cold, hyperkalemic ([K+] = 25 mM) crystalloid cardioplegic solution for 1 hour. In another group (n = 6), hearts were arrested and then reperfused with warm blood for 1 hour, or pigs were placed on CPB without cardioplegia (n = 6). Coronary arterioles were studied in a pressurized, no-flow state with video-microscopy. Myogenic reactivity was examined to stepwise increases in intraluminal pressure from 10 to 100 mmHg. The vessel diameter was normalized to the diameter at 50 mmHg after application of papaverine (10-4 M). In vessels from non-instrumented control hearts (n = 6) and vessels in the CPB group, myogenic contraction was observed with pressures g40 mmHg. However, CPB significantly shifted the pressure-diameter relation upward (p l 005 vs control). suggesting a decrease in the intrinsic tone. Cardioplegic arrest, with or without reperfusion, decreased myogenic reactivity with an upward displacement of the pressure-diameter relation (both p l 0.05 vs control). Myogenic reactivity of the control vessel was not altered after mechanical denudation of the endothelium, or following pretreatment with NG-nitro-L-arginine or indomethacin. However, blockade of the ATP-sensitive potassium channel by glybenclamide significantly attenuated the cardioplegia-induced decrease in myogenic reactivity (p l 0.05). These results suggest that coronary microvascular myogenic reactivity and the intrinsic tone are reduced following hyperkalemic cardioplegia, and that CPB alone preserves myogenic reactivity but reduces the intrinsic tone of the vascular smooth muscle. Download : Download high-res image (71KB) Download : Download full-size image
OmpD but not OmpC is involved in adherence of Salmonella enterica serovar typhimurium to human cells

Conflicting reports exist regarding the role of porins OmpC and OmpD in infections due to Salmonella enterica serovar Typhimurium. This study investigated the role of these porins in bacterial adhe...
Gender differences in the association of alcohol intoxication and illicit drug abuse among persons arrested for violent and property offenses.

Abstract Purpose: To explore the associations between violent and other crimes, and alcohol intoxication and recent use of cocaine, marijuana, and other drugs among men and women arrestees and examine gender differences in these relationships. Methods: We conducted a secondary analysis of 1998 using Arrestee Drug Abuse Monitoring (ADAM) system data using a sample of 9242 male and 2594 women arrested for violent and property offenses in 35 cities. Logistic regression was used to predict arrest for a violent offense (rather than a property crime) from drug- and alcohol-related, and other variables. Results: Both gender and alcohol intoxication are significantly related to arrest for a violent offense. However, the intoxication effects (in the absence of cocaine) are more than three times as great for female (Exp(β)=5.59) as male arrestees (Exp(β)=1.74), while the combined effects of alcohol and cocaine predict a property offense for women but are insignificant for men. Implications: To achieve further reductions in violent crime, intervention strategies need to focus on reducing alcohol intoxication as well as illicit drug use. Research on the role of alcohol on women's aggression and violence also is suggested.
Geometry of interaction of metal ions with histidine residues in protein structures

An analysis of the geometry and the orientation of metal ions bound to histidine residues in proteins is presented. Cations are found to lie in the imidazole plane along the lone pair on the nitrogen atom. Out of the two tautomeric forms of the imidazole ring, the NE2-protonated form is normally preferred. However, when bound to a metal ion the ND1-protonated form is predominant and NE2 is the ligand atom. When the metal coordination is through ND1, steric interactions shift the side chain torsional angle, chi 2 from its preferred value of 90 or 270 degrees. The orientation of histidine residues is usually stabilized through hydrogen bonding; ND1-protonated form of a helical residue can form a hydrogen bond with the carbonyl oxygen atom in the preceding turn of the helix. A considerable number of ligands are found in helices and beta-sheets. A helical residue bound to a heme group is usually found near the C-terminus of the helix. Two ligand groups four residues apart in a helix, or two residues apart in a beta-strand are used in many proteins to bind metal ions.
Using Team Learning in Business and Organizational Communication Classes

The past decade has produced a growing body of evidence suggesting small group-based instructional methods can promote the achievement of a variety of desirable higher educational outcomes. Therefore, within college and uni versity settings, group-oriented instruction has increased. Team Learning goes beyond using temporary groups or assigning occasional group activities. With this approach, students spend approximately 80 percent of their in-class time working in permanent and heterogeneous teams. The system, when used prop erly, appears to overcome many of the potential problems with using small groups. The methodology empowers both instructor and students. The instruc tor becomes a facilitator and manager of learning rather than the "spoon feeder" of information. The students become active and responsible partici pants in the learning process rather than passive recipients. The process facili tates effective teamwork in settings where teams gain first-hand experience with the kind of team dynamics they...
The interaction of horizontal eddy transport and thermal drive in the stratosphere

The two processes that determine the average state of the circulation; i.e., horizontal eddy transport and thermal dissipation, are examined, and the effects of their interaction on circulation and on tracer distribution in the stratosphere are investigated using barotropic calculations on the sphere. It is shown that eddy advection tends to homogenize the meridional gradient Q at low latitudes, while thermal dissipation restores the gradient after episodes of mixing.
Light composite fermions

Abstract In this paper we consider the possibility that QCD-like theories can lead to massless or near-massless composite fermions. The method of analysis relies on a conjectured equivalence between the confined and Higgs phases of certain non-abelian gauge theories. This “complementarity” principle allows us to analyze a theory as if the Higgs phenomenon occurred and then reinterpret the results in the language of composite gauge singlets. Those fermions which remain massless in the Higgs picture may then be interpreted as massless fermionic composites. The principle of complementarity, when applied to a class of extended technicolor models, implies that quarks and leptons are composites bound at a scale of order 1–100 TeV.
On the Use of Price Ratio in Aggregate Supply Response: Some Evidence from the Poultry Industry

The specification of supply/demand relationships has received considerable attention in agricultural economics (Heien 1977). Economic theory has helped provide a basis for the specification of such relationships, one of its contributions being the proposition that prices should be interpreted only in relative terms. This has had a profound influence on model building in agricultural economics, leading a number of researchers to avoid the use of absolute prices in economic analysis. For this reason, numerous market models of the agricultural economy use price ratios as explanatory variables (e.g., Chen; Chen et al.; Heien, 1976; Gerra; Kulshreshtha and Wilson; Rahn; Talpaz; Morzuck et al.; Houck and Gallagher; Wilson et al.); these examples suggest that the use of such ratios is fairly widespread in econometric modeling of the crop and livestock sectors. One of the best examples of price ratios is the “feed cost to price” ratio commonly used in the analysis of livestock supply response. Indeed, since feed cost constitutes a major part of the total production cost in livestock activities, the “feed cost to price” ratio is often considered a proxy for profitability. For this reason, data on such ratios are regularly published for various livestock activities (e.g., USD A). Also, “feed cost to price” ratios are often employed in the specification of models of livestock supply response, (e.g., Chen; Chen et al.; Heien 1976; Gerra; Kulshreshtha and Wilson; Rahn; Talpaz). However, not all models of aggregate supply response follow this approach. For example, Freebairn and Rausser, and Arzac and Wilkinson, use prices as separate variables rather than in ratio forms in their models. In particular, they do not employ price ratios in their livestock and crop supply equations. The existence of these different approaches raises questions about the appropriateness of the use of price ratios in the modeling of aggregate supply.
Innate and adaptive immune responses regulated by glycogen synthase kinase-3 (GSK3)

In just a few years, the view of glycogen synthase kinase-3 (GSK3) has been transformed from an obscure enzyme seldom encountered in the immune literature to one implicated in an improbably large number of roles. GSK3 is a crucial regulator of the balance between pro- and anti-inflammatory cytokine production in both the periphery and the central nervous system, so that GSK3 inhibitors such as lithium can diminish inflammation. GSK3 influences T-cell proliferation, differentiation and survival. Many effects stem from GSK3 regulation of critical transcription factors, such as NF-kappaB, NFAT and STATs. These discoveries led to the rapid application of GSK3 inhibitors to animal models of sepsis, arthritis, colitis, multiple sclerosis and others, demonstrating their potential for therapeutic intervention.
Method for Evaluating One-Dimensional Path Integrals

A practical method is developed for calculating numerically one-dimensional path integrals for an arbitrary potential $V(x)$. For the oscillator potential $V(x)=\frac{k{x}^{2}}{2}$ the well-known analytic solution is obtained. To illustrate the numerical convergence of this method the path integral for the Ginzburg-Landau potential, $V(x)=\ensuremath{-}\frac{A{x}^{2}}{2}+\frac{B{x}^{4}}{4}$, is calculated over a range of the positive constants $A$ and $B$ and compared with numerical solutions of the Schr\"odinger equation.
Comparison of Output SINR and Receiver C/N_0 for GNSS Adaptive Antennas

Antenna arrays with space-time adaptive processing (STAP) are commonly utilized to allow the reception of signals in harsh interference environments. The primary applications of STAP have been radar and communications systems, where the STAP weights are optimized for output signal-to-interference-plus-noise ratio (SINR); however, there is increasing demand for STAP in time-of-arrival (TOA) estimation applications, such as global navigation satellite system (GNSS) receivers. It is understood that TOA estimation performance is primarily dependent on receiver postcorrelation carrier-to-noise ratio (C/N0). In this study, the distinction between SINR and C/N0 is established, and a performance analysis of the common STAP algorithms is performed in the presence of interference. It is demonstrated that output SINR is an inadequate indication of GNSS receiver C/N0 performance. As a result, caution should be used when measuring the relative performance of different STAP algorithms in GNSS applications. Consequently, the present work develops a novel STAP algorithm which maximizes C/N0. Additionally, the performance of common STAP algorithms is analyzed in the context of this performance bound, and it is demonstrated that, in many cases, their performance is near optimal.
Local field distribution in random metal–dielectric films; theory and experiment

Abstract The local field properties of metal–dielectric films are investigated in terms of the probability distribution function (PDF). For metal coverage p , close to the percolation threshold we obtain a wide, lognormal PDF which for low metal concentrations gradually transforms into a scaling, power-law distribution function. Strong enhancement of the local fields in a broad spectral range is verified by an exact numerical procedure. In experimental studies, metal–dielectric films were synthesized by a pulsed laser deposition technique, and their optical properties were investigated using near-field optical microscopy. The experimentally and numerically obtained probability functions are found to be in good agreement.
Effectiveness of a new non-thrombogenic bio-adhesive in microvascular anastomoses.

Negatively-charged fibrin glue was successfully prepared by combining human cryoprecipitate with succinic anhydride. The resulting bio-adhesive was tested for thrombogenicity and tensile strength by applying it to three groups of Sprague-Dawley rat femoral-artery anastomoses (6 suture, 2 suture, and no suture anastomoses). Anastomoses were tested by a standard patency test over 7 days. Both the 6-suture and 2-suture anastomoses with negatively-charged fibrin glue had 100 percent patency rates and no pseudoaneurysm formation over 7 days. When positively-charged fibrin glue was applied to sutured anastomoses, patency rates decreased gradually to 50 percent over 7 days. Fibrin glue alone (whether negatively- or positively-charged) does not have the tensile strength to maintain an anastomosis without sutures. However, when applied to a two-suture anastomosis, the breaking strength of the anastomosis is more enhanced by the negatively-charged fibrin glue
Functional programming and the two-pass assembler

The classical two-pass assembly process is adapted for implementation in a functional programming language similar to Backus' FP language. We show that the parallelism inherent in FP languages allows radical changes in the design of such well-known algorithms as the two-pass assembler.
Somatosensory responses in normal aging, mild cognitive impairment, and Alzheimer’s disease

As a part of a larger study of normal aging and Alzheimer's disease (AD), which included patients with mild cognitive impairment (MCI), we investigated the response to median nerve stimulation in primary and secondary somatosensory areas. We hypothesized that the somatosensory response would be relatively spared given the reported late involvement of sensory areas in the progression of AD. We applied brief pulses of electric current to left and right median nerves to test the somatosensory response in normal elderly (NE), MCI, and AD. MEG responses were measured and were analyzed with a semi-automated source localization algorithm to characterize source locations and timecourses. We found an overall difference in the amplitude of the response of the primary somatosensory source (SI) based on diagnosis. Across the first three peaks of the SI response, the MCI patients exhibited a larger amplitude response than the NE and AD groups (P < 0.03). Additional relationships between neuropsychological measures and SI amplitude were also determined. There was no significant difference in amplitude for the contralateral secondary somatosensory source across diagnostic category. These results suggest that somatosensory cortex is affected early in the progression of AD and may have some consequence on behavioral and functional measures.
Characterization of insulin-like growth factor binding proteins (IGFBP) and regulation of IGFBP-4 in bone marrow stromal cells

Summary. Bone marrow stromal cells synthesize and secrete insulin-like growth factor (IGF)-I and IGF-binding proteins (IGFBP). IGFBPs may modulate the action of IGF-I or IGF-II on haemopoiesis. However, the specific IGFBPs produced by various stromal cell types have not been identified. We examined six different stromal phenotypes for IGFBP protein and IGFBP-1 to -6 mRNA expression. [125I]IGF-I ligand blot analysis of conditioned medium demonstrate different patterns of IGFBP secretion by each cell type. The most prominent IGFBPs were 24 and 29 kD species, consistent with IGFBP4 and IGFBP5, respectively. RNase protection assays demonstrate that, overall, stromal cells express IGFBP-2 to -6 mRNAs, with IGFBP4, IGFBP5 and IGFBP6 mRNAs predominating. Since agents that modulate cAMP levels may influence haemopoiesis via the release of stromal-derived cytokines, we determined the effect of forskolin, a cAMP agonist, on IGFBP4 expression in TC-1 cells. Forskolin (10 5 M) up-regulated IGFBP4 mRNA and protein secretion in a time-dependent manner. These findings suggest that IGFBP-4, -5 and -6 released by stromal cells may be key modulators of the haemopoietic response to IGFs. Release of IGFBP4 by agents that increase cAMP may be an important mechanism involved in regulating IGF bioavailability in the marrow microenvironment.
Acute leukemia in two patients with hemophilia

A 10-year-old classic hemophiliac and 1.5-year-old child with hemophilia B who developed acute lymphocytic and acute myelomonocytic leukemia respectively are presented. No changes in coagulation status of the patients were observed. It is suggested that hemophiliacs should be regarded as "population at risk" for the development of leukemia.
“A Mirror of the Times”: The Catilinarian Conspiracy in Eighteenth-Century British and American Political Thought

In the eighteenth century, the Catilinarian conspiracy, as portrayed by Sallust and Cicero, provided a cautionary tale for British and American political writers, both Whig and Tory, about the destabilizing nature of debt and the dangers of radical democracy. In the wake of the South Sea Bubble crisis of the early 1720s, writers like Thomas Gordon used the conspiracy to expose the dangers of political demagoguery and the precarious luxury that accompanied expanded credit. During the American Revolutionary period, Tories and Federalists branded as “Catilines” those who, like Daniel Shays, mobilized the forces of radical democracy with the promise of debt relief. Throughout the eighteenth century, Catiline represented the danger to a mixed constitution of demagogues who attempted to rally the democratic element in society against the privileges of the patrician class.
Drug effects upon force and duration of response during fixed-ratio performance in rats

Abstract Rats responded on a tandem FR24CRF CRF CRF CRF schedule of water reinforcement by paw-pressing a silent, isometric, force-sensing manipulandum. Oral dose ranges of d-amphetamine, chlordiazepoxide, chlorpromazine, and dantrolene were evaluated for their effects on this schedule-controlled behavior. Peak force, duration and interresponse time (IRT) of individual responses were recorded with a laboratory computer system. Conjoint examination of these three dependent variables revealed that the intensitive measures of response (i.e., peak force and duration) provided information about drug effects that could not be detected with the conventional IRT measure alone. More specifically, peak force was elevated by d-amphetamine at 1.6 mg/kg during the FR component, but IRT was unaffected at this dose. At 3.2 mg/kg, d-amphetamine decreased peak force and lengthened IRT during the FR component. Chlordiazepoxide increased peak force up to the highest dose examined (27.0 mg/kg), whereas dantrolene decreased peak force. Chlorpromazine did not affect peak force but did increase response duration. Higher doses of chlordiazepoxide, chlorpromazine, and dantrolene lengthened IRT during the FR component. For all three dependent variables drug effects were generally less pronounced or altogether undetected in the CRF component. The results are discussed in relation to explanatory principles such as rate-dependency and stereotyped behaviors.
On the limits of validity of effective dispersion models for bulk reactions

Abstract Dispersion models containing a single effective dispersion coefficient have been extensively used in the literature to predict the performance of chemical reactors. In recent years, there is considerable debate on whether the effective dispersion relations determined in the absence of reaction are also valid in the presence of a reaction, especially for the case of bulk reactions. We examine this problem in some detail and show that for the two most commonly used effective dispersion models (axial dispersion and tanks-in-series or cell model), the widely used relationship N=Pe/2, (Pe≫1, N= number of cells and Pe = Peclet number), derived in the absence of a reaction, also holds for all slow reactions characterized by 0⩽Da| f ′(c N )| 2/3 . Here, Da is the Damkohler number and f ′(c N ) is the derivative of the normalized reaction rate at the exit concentration c N of the cell model. For Da values exceeding this upper bound (fast reaction regime), the model predictions diverge, or equivalently, the effective dispersion coefficient concept is not valid. We show that the same result applies for transient behavior of the discrete and continuous (PDE) models provided Da is replaced by Da 2 +ω 2 , where ω is the dimensionless forcing frequency. We also derive similar bounds for two other commonly used dispersion models, namely, the recycle and interphase resistance models. A formula for choosing the mesh size for fast reactions so that the discrete and continuous models have the same qualitative features is also presented. The analytical results derived for linear reactions are validated for nonlinear kinetics using numerical simulations. Some new results and comparisons are also presented at the other extreme of near perfect mixing.
Eclipses by an elliptical torus

A general procedure for computing the effects of eclipses by a torus, including both the outer horizon and the inner or hole horizon, was developed. The procedure can be used for any of the simple figures of revolution encountered in binary-star models. That is, the thickness can be made negligible to produce a thin ring, the hole radius can be set to zero to yield a thin disk, the radius to the center of the elliptical meridian section can be brought to zero to give an ellipsoid of revolution, or the equatorial axis of the elliptical meridian section can be made to equal zero to produce a section of a right circular cylinder.
Update On Professionalism And Standards For Infrared Sensing Devices

Infrared sensing may seem a relatively new scientific discipline but in reality the existence of infrared was noted as early as 1800 when Sir William Herschel wrote on the subject. He discovered the "invisible rays" as he called them while developing filters for protecting his eyes while observing the sun. Herschel described this effect in 1801 in two papers. The term "infrared" was not coined until the 1880's. The author of the term is not known but in Latin infra means below or beneath, possibly implying beneath the red. Using a prism and a sensitive mercury - in glass thermometer, William Herschel measured the radiation from fires, candles, and kitchen stoves demonstrating a detector able to measure radiation in this infrared region and raising questions about the connection between light and heat. In 1840, Herschel's son John developed a radiation detection process based on the differential evaporation of a thin film of oil to form a "heat picture." This process was improved by Czerny in 1929 and is still in use today as the "evaporagraph." In 1843 Becquerel found that certain materials phosphoresced when exposed to infrared radiation. During the 1880's several highly sensitive new detectors were developed most notable being the Langley bolometer. In 1901 Langley and Abbot reported the use of a bolometer that could detect the heat from a cow at a distance of 1/4 mile. Case in 1917 developed the thallous sulfide detector, the first use of the photoconductive effect in the infrared. Development continued in detector technology especially by the Germans during World War II. Following the war the efforts were on,radiometry. During the 1950's non-military applications for these devices grew rapidly'. Now, point radiometry is an established quantitative technology with thousands of units in place for remote temperature measurement and control. The instruments are calibrated for temperature with appropriate scale, emittance correction, voltage output, and internal reference. Infrared imaging systems have developed in the 60's and are currently approaching tne quantitative level as they are being integrated into computer processing. Technology improvements provide on-line video tape recording, quantification, computer interfacing, and graphics. Instrument improvement is an on-going active process being pushed by military, space, and industrial applications. Associated with the new technology must be the development of an educational process which provides the user with information sufficient to properly assimilate the information derived from the instrument.© (1984) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Water-soluble platinum and palladium nanoparticles modified with thiolated β-cyclodextrin

Pt and Pd nanoparticles can be modified with surface-attached cyclodextrin receptors leading to water-soluble materials that exhibit catalytic activity for the hydrogenation of allylamine.
Dynamic endogenous association of neurofilament mRNAs with K-homology domain ribonucleoproteins in developing cerebral cortex.

Abstract The low, middle, and high molecular mass neurofilament subunit proteins (NF-L, NF-M, and NF-H) co-polymerize to form neurofilaments (NFs). During development, NF subunit expression is highly regulated, and in neurodegenerative disease, aberrant regulation of this expression can lead to the formation of harmful aggregates. NF expression in both development and disease is under significant post-transcriptional control, but the specific ribonucleoproteins (RNPs) involved are only poorly understood. Previously, mass spectrometry on affinity purified proteins from rat brain identified three K-homology (KH) domain RNPs – hnRNP K, hnRNP E1, hnRNP E2 – as being capable of binding NF-M RNA. In the current study, to determine whether these RNPs associate with NF mRNAs endogenously, we performed a co-immunoprecipitation assay on homogenates of postnatal and developing rat cerebral cortex. We found that all three NF mRNAs indeed associated endogenously with these RNPs and that the degree of this association changed during postnatal development, a period when NF expression is under significant post-transcriptional control. The degree of these associations changed independently of the abundance of either the RNPs or the NF messages, indicating that the RNA–protein interactions themselves are directly regulated. This study is consistent with a model whereby these RNPs and NF mRNAs are components of a dynamic post-transcriptional regulatory module that influences the cytoskeletal compositions of neurons.
Ignition delay times of low-vapor-pressure fuels measured using an aerosol shock tube

Abstract Gas-phase ignition delay times were measured behind reflected shock waves for a wide variety of low-vapor-pressure fuels. These gas-phase measurements, without the added convolution with evaporation times, were made possible by using an aerosol shock tube. The fuels studied include three large normal alkanes, n -decane, n -dodecane and n -hexadecane; one large methyl ester, methyl decanoate; and several diesel fuels, DF-2, with a range of cetane indices from 42 to 55. The reflected shock conditions of the experiments covered temperatures from 838 to 1381 K, pressures from 1.71 to 8.63 atm, oxygen concentrations from 1 to 21%, and equivalence ratios from 0.1 to 2. Ignition delay times were measured using sidewall pressure, IR laser absorption by fuel at 3.39 μm, and CH * and OH * emission. Measurements are compared to previous studies using heated shock tubes and current models. Model simulations show similar trends to the current measurement except in the case of n -dodecane/21% O 2 /argon experiments. At higher temperatures, e.g. 1250 K, the measured ignition delay times for these mixtures are significantly longer in lean mixtures than in rich mixtures; current models predict the opposite trend. As well, the current measurements show significantly shorter ignition delay times for rich mixtures than the model predictions.
Design and operation of a sequentially-fired pulse forming network for non-linear loads

While the construction of a linear pulse forming network (PFN) for a constant load impedance is relatively easy, the process is more difficult for a nonlinear or time-varying load. A passive PFN can certainly be synthesized for nonlinear loads, but is usually large and lacks the flexibility to be truly useful in most practical and research applications. This investigation describes the design and construction of a sequentially-fired pulse forming network (SFPFN) that maintains constant voltage and current for a nonlinear load. Operation of the SFPFN consists of charging multiple capacitor banks (or modules) to various levels and sequentially firing these banks into the load at appropriate times. The load and its characteristics determine the module charge voltage. An added benefit with the SFPFN is real-time computer monitoring and control allowing the PFN modules to be charged from a single prime power source via a group of switching relays. The nonlinear load used in this investigation is a helical coil electromagnetic launcher (HCEL). The SFPFN is also tested with a linear load consisting of a pulsed field coil. The nonlinearity of the HCEL is well-known with a factor of 2 change in winding resistance due to joule heating and a large variation in terminal voltage due to changes in the armature back-voltage. Experimental measurements show the SFPFN can deliver a relatively constant current pulse on the order of 5-15 kA into the HCEL load for a pulse length up to 8 ms. The maximum SFPFN operating voltage is 900 V with a total stored energy of 125 kJ. Scaling the SFPFN to larger or smaller pulse amplitudes or lengths is possible.
Children's abilities to recognize a "good" person as a potential perpetrator of childhood sexual abuse.

Abstract Objective This study examined the ability of children to recognize “good” people as potential perpetrators prior to and after completing a personal safety program. There were three objectives to the study. The first was to determine whether young children could recognize the inappropriateness of a sexual request coming from people described as either “good” or “bad.” Second, the study examined whether preschoolers could be educated to recognize inappropriate touch requests regardless of the good/bad descriptor. Finally, we explored if children's ability to learn the recognition skill depended upon their age. Methods Ninety-three, primarily Hispanic (72%) preschool children ( M age = 3.9 years) completed the Body Safety Training program (BST; Wurtele, 2007 ), a classroom-based behavioral program. They responded to questions about “good” and “bad” people requesting to touch their private parts prior to and after the educational program. Results At pre-testing, children had more difficulty recognizing inappropriate touch requests when made by “good” people compared to “bad” people. After completing the BST program, children improved in their ability to recognize the inappropriateness of requests made by both “good” and “bad” people. At pretesting, correct responding varied across age groups, with a greater percentage of older children (age 5) correctly responding to the “bad” cases compared to 3- and 4-year olds. At post-testing, a marginally significant age difference was found for cases involving “good” people and significant differences were found for cases involving “bad” people. Almost all 4- and 5-year-old children (94% and 96%, respectively) correctly responded to these inappropriate requests compared with only 71% of the 3 year olds. Conclusion Pre-test results demonstrated that young children had difficulty recognizing the inappropriateness of a request when it was made by a “good” person. Post-test findings demonstrated that children as young as 3 years of age can learn the inappropriateness of such requests even when coming from “good” people, although 3 year olds had more difficulty recognizing inappropriate-touch requests compared to 4- and 5-year-old children. Practice implications Results support the challenge of helping young children learn to recognize potential perpetrators, especially those described as “good” people.
Treating cardiovascular disease with antimicrobial agents: a survey of knowledge, attitudes, and practices among physicians in the United States.

To assess physicians' knowledge, attitudes, and prescribing behaviors with regard to the association between Chlamydia pneumoniae and cardiovascular disease, we surveyed 750 physicians in Alaska, 1172 in West Virginia, and 569 infectious disease (ID) specialists in a nationwide network during February-May 1999. Eighty-five percent knew of the association between C. pneumoniae and atherosclerosis, but this awareness was more common among ID specialists and cardiologists than among generalists (96% vs. 77%; P <.001). Knowledge scores were significantly higher among ID specialists and cardiologists (P <.001) and among physicians who saw relatively more patients who had myocardial infarction and/or were at risk of atherosclerotic disease. Four percent of physicians had treated or recommended treating cardiovascular diseases with antimicrobial agents; this percentage was significantly higher among cardiologists, physicians who empirically treat patients with peptic ulcers with antimicrobial agents, and physicians with a relatively high knowledge score.
Can the Intestinal Dysmotility of Critical Illness be Differentiated from Postoperative Ileus

Gastrointestinal dysmotility is commonly noted in the intensive care unit and postoperative settings. Characterized by delayed passage of stool and flatus, nausea, vomiting, and abdominal distention, the condition is associated with nutritional deficiencies, risk of aspiration, and considerable allocation of health care resources. Knowledge of gastrointestinal function in health and illness continues to expand. While the factors that precipitate ileus differ between postoperative and critically ill patients, the two clinical scenarios seem to have similar mechanisms and share many of the same pathophysiologic patterns. By reviewing and comparing the literature on the respective mechanisms and contributing factors generated in these separate clinical settings, a common more comprehensive management strategy may be derived with the potential for newer innovative therapeutic options.
Infinite Dimensional Fock Spaces and an Associated Generalized Laplacian Operator

Quantum field theory has a long history of cooperation between physicists and mathematicians. The approach in this paper utilizes the theory developed in generalized functions. This technique was pioneered by Dr. Paul Dirac. His results of the 1920’s still remain a very elegant treatment of the theory. A recent publication [9] written by Dirac in 1966 gives a concise assessment of the subject. Many other contributors such as Bergmann, Bogoliubov, Cholewinski, Colombeau, Friedrichs, Kastler, Kristensen, Mejblo, Poulsen, Rzewuski, Schiff, Shapiro, and Wightman incorporate generalized functions into their development.
P2P-R protein localizes to the nucleolus of interphase cells and the periphery of chromosomes in mitotic cells which show maximum P2P-R immunoreactivity

P2P-R is a nuclear protein that can bind both p53 and Rb1. Its functions include roles in the control of RNA metabolism, apoptosis, and p53-dependent transcription. The expression of P2P-R also is repressed in G1 arrested terminally differentiated cells. The current studies therefore evaluated if P2P-R undergoes cell cycle-associated changes in its abundance and/or localization. Western blots show that relative to G0 quiescent cells, P2P-R protein levels are higher in populations of G2/M cells prepared by the physiological parasynchronization technique of serum deprivation followed by serum stimulation. More striking is the > 10-fold enrichment of P2P-R protein in specimens of highly purified mitotic cells prepared by the mitotic shake-select technique, or by synchrony with the mitotic spindle disruption agents nocodazole or vinblastine. These changes in P2P-R protein occur without a concomitant change in P2P-R mRNA expression suggesting that P2P-R immunoreactivity increases during mitosis. Confocal microscopy next established the localization of P2P-R to nucleoli in interphase cells and at the periphery of chromosomes in mitotic cells that lack nucleoli. The high levels of P2P-R localized to the periphery of chromosomes in mitotic cells suggest that P2P-R shares characteristics with other nucleolar proteins that associate with the periphery of chromosomes during mitosis. These include: nucleolin, B23, Ki67, and fibrillarin.