cssi/SciSciGPT-SciSciNet huggingface dataset:
PS1-06: Radiation Oncology Data in Integrated Healthcare Delivery Systems

Background/AimsRadiation oncology is an integral component of high-quality cancer care, in both curative and palliative settings. Nationally, concern exists regarding access, quality, and diffusion of radiation oncology technologies, especially newer high-cost modalities. This study is exploring capture and quality of radiation oncology data at three CRN sites—GHC, KPCO, and KPNW. Our aims are to identify the magnitude and sources of data leaks and to expand capture of variables related to radiation therapy, (e.g. anatomic focus, radiation type, numbers and duration of sessions, and total radiation dose). Our ultimate goal is to conduct comparative effectiveness research using the full spectrum of cancer treatments.MethodsThe current sites also participated in Burden of Cancer Care, an NCI-funded R01 study (PI: Mark C. Hornbrook) of cancer cases and matched, non-cancer controls. A comprehensive list of radiation oncology-related codes were developed using interviews of local billing experts, project lists, Internet searches, and review of CPT-4/HCPCC/ICD-9-CM code books. Radiation oncologists and business managers were interviewed to develop diffusion timelines and identify new data sources. A SAS program was written and distributed for use in Burden datasets to compare encounter- and claims-based evidence of radiation receipt among enrollees between 2000–2008, in the presence or absence of cancer diagnosis by tumor registry and/or claims/encounter data.ResultsWhile use of radiation codes differ (e.g., facility revenue codes), the proportion of patients receiving radiation was similar across sites (N=27,210 of 627,682 cases and controls). About 85% (N=23,222) of patients receiving radiation therapies were identified as having cancer via tumor registry and encounter-/claims-based sources, with the remaining 15% identified by encounter or claims only. Of those identified by both methods, 99% (N=22,984) received radiation after cancer diagnosis. Overall 4.5% (N=1,228) of radiation recipients did not have a cancer diagnosis in the study period. Of those with data (N=985), the majority had either a cancer diagnosis outside the study period (23%, N=231) or a benign tumor (77%, N=754). Additional treatment data exists in network-based radiation departments and efforts are ongoing to integrate these data at two sites.DiscussionFurther work is necessary to ensure radiation oncology data are comprehensive and complete across CRN sites.
Surface chemical control of the electronic structure of silicon nanowires: Density functional calculations

Silicon nanowires NWs have potential use in many electronic and photonic applications. In this study, we have systematically investigated the modification of Si NW electronic structure for different sized NWs and different surface coverage H, Br, Cl, and I using ab initio density functional theory calculations. The surface chemistry is shown to have strong effects, comparable to that of quantum confinement, on the band structure of Si NWs. Electronic structure analysis reveals the primary cause of the band gap change is the suppression of surface states as determined by the strength of the surface bonds. The results elucidate surface chemical control of NW electronic structure and illustrate an example of simulation-based design characterization of nanoelectronic components.
Pure Gauge SU(3) Lattice Theory on an Array of Computers

We report on a pure gauge SU(3) lattice theory computation performed on an array of 64 microprocessors interconnected as a 2/sup 6/ hypercube and having the cumulative power of approximately eight VAX11/780's. The availability of a substantial number of computer cycles, coupled with an improvement in the algorithm, made possible a high-statistics determination of the heavy-quark potential on a 12/sup 3/ x 16 lattice.
Further studies on the pharmacology of a false cholinergic transmitter, (2-hydroxyethyl) methyldiethylammonium (diethylcholine).

Abstract The pharmacology of a possible false cholinergic transmitter, (2-hydroxyethyl) methyldiethylammonium (diethylcholine, DEC) was studied with various preparations. It was found to inhibit the neuromuscular transmission of frog sciatic nerve-gastrocnemius muscle in vitro with ED50 of 1.93 (0.66 - 5.79) × 10−4 M. DEC was also found to inhibit dog chorda tympani-Wharton's duct (postganglionic parasympathetic neuro-effector junction) and cat superior cervical ganglionnictitating membrane (sympathetic ganglion) preparations in vivo with ED50's of 6.2 (1.8 – 21.1) mg/kg and 12.0 (5.7 - 25.2) mg/kg, respectively. After blockade of these preparations with DEC, the former was still responsive to intravenous injection of pilocarpine (1 mg/kg) and choline (10 mg/kg) and the latter to close arterial injection of acetylcholine (100 μg/injection) and choline (3 mg/min infusion). These results support the idea that DEC paralyzes cholinergic neurons possibly through false cholinergic transmission without blocking the cholinergic receptor at the post-junctional membrane.
High prevalence of normal serum albumin in NASH patients with ascites: a retrospective analysis.

Summary Background Ascites usually occurs in the setting of end-stage liver disease and low serum albumin and is associated with increased mortality. However, some patients develop ascites despite normal serum albumin (NSA), when a higher portal pressure and/or enhanced renal sodium retention would be expected. This study investigated the relationship between the hepatic venous pressure gradient (HVPG) and serum albumin in ascitic patients with different etiologies of cirrhosis and mortality. Methods Records of all patients with non-malignant ascites who underwent HVPG measurement from 2005 to 2009 were reviewed. Results One hundred and thirty-eight 138 patients met inclusion criteria; 18.8% had NSA. No difference in sodium excretion or diuretic use was noted in patients with and without NSA. NASH patients were more likely to have a NSA (34.2% vs 12.4%; P = 0.001) as well as lower HVPG (15 vs 17.9 mmHg; P = 0.009) compared to other etiologies. MELD and HVPG predicted overall survival. However, mortality did not differ by disease etiology, though NASH patients had lower CTP (7.6 vs 8.5; P P = 0.09) scores, particularly among patients who died. Conclusions In patients with ascites and NSA, there were no increase in HVPG or urinary sodium retention. NASH patients with ascites had lower HVPG and a higher prevalence of NSA. They also had a higher mortality relative to MELD and CTP scores in other patients. In these patients, mechanisms other than portal and oncotic pressures and sodium retention play a role in ascites development, and increase mortality rate when complicated by low albumin.
Diffusion model in ion channel gating. Extension to agonist-activated ion channels.

Previously, we described a model which treats ion channel gating as a discrete diffusion problem. In the case of agonist-activated channels at high agonist concentration, the model predicts that the closed lifetime probability density function from single channel recording approximates a power law with an exponent of -3/2 (Millhauser, G. L., E. E. Salpeter, and R. E. Oswald. 1988a. Proc. Natl. Acad. Sci. USA. 85: 1503–1507). This prediction is consistent with distributions derived from a number of ligand-gated channels at high agonist concentration (Millhauser, G. L., E. E. Salpeter, and R. E. Oswald. 1988b. Biophys. J. 54: 1165–1168.) but does not describe the behavior of ion channels at low activator concentrations. We examine here an extension of this model to include an agonist binding step. This extended model is consistent with the closed time distributions generated from the BC3H-1 nicotinic acetylcholine receptor for agonist concentrations varying over three orders of magnitude.
A siphon mechanism for supplying prominence mass

We examine a siphon-like mechanism for moving mass from the chromosphere to a gravitational well at the top of a magnetic loop to form a prominence. The calculations assume no apriori flow velocity at the loop base. Instead heating in the loop legs drives the flow. The prominence formation process requires two steps. First, the background heating rate must be reduced to on the order of 1 % of the initial heating rate required to maintain the coronal loop. This forms an initial condensation at the top of the loop. Second, the heating must take place only in the loop legs in order to produce a pressure differential which drives mass up into the well at the top of the loop. The heating rate in the loop must be increased once the prominence has begun to form or full prominence densities can not be achieved in a reasonable time. We conclude that this heating driven siphon-like mechanism is feasible for producing and maintaining prominences.
2D NMR Investigations of the Rotation of Axial Ligands in Six-Coordinate Low-Spin Iron(III) and Cobalt(III) Tetraphenylporphyrinates Having 2,6-Disubstituted Phenyl Rings: Quantitation of Rate Constants from 1H EXSY Cross-Peak Intensities

Phase-sensitive NOESY/EXSY experiments have been utilized to measure the rates of axial ligand rotation for (tetramesitylporphyrinato)iron(III) and -cobalt(III) bis(2-methylimidazole), [(TMP)Fe(2-MeImH)2]+ClO4- and [(TMP)Co(2-MeImH)2]+BF4-, and several related complexes at various low temperatures. The derivations of the expressions for EXSY cross-peak volumes (Ernst, R. R.; Bodenhausen, G.; Wokaun, A. Principles of Magnetic Resonance in One and Two Dimensions; Clarendon Press: Oxford, U.K., 1992; chapters 6 and 9) as a function of mixing time τm, longitudinal relaxation time T1, and chemical exchange rate constant, k, have been extended to the case of cyclic four-site chemical exchange having a single rate constant. Cross-peak volumes were fit to the expressions, and the rate constants were calculated using a computer fitting program developed in this laboratory. The dependence of the reliability of the rate constant on T1, τm, and other experimental factors is discussed. The temperature dependence of t...
Molecular Tests of Phylogenetic Taxonomies: A General Procedure and Example Using Four Subfamilies of the Lizard Family Iguanidae

Abstract A general procedure is described for examining when results of molecular phylogenetic analyses warrant formal revision of taxonomies constructed using morphological characters. We illustrate this procedure with tests of monophyly for four subfamilies in the lizard family Iguanidae using 1561 aligned base positions (838 phylogenetically informative) of mitochondrial DNA sequences, representing coding regions for eight tRNAs, ND2, and portions of ND1 and COI. Ten new sequences ranging in length from 1732 to 1751 bases are compared with 12 previously reported sequences and 67 morphological characters (54 phylogenetically informative) from the literature. New morphological character states are provided for Sator. Phylogenies derived from the molecular and combined data are in agreement but both conflict with phylogenetic inferences from the morphological data alone. Strong support is found for the monophyly of the subfamilies Crotaphytinae and Phrynosomatinae. Monophyly of the Iguaninae is weakly supported in each analysis. All analyses suggest that the Tropidurinae is not monophyletic but the hypothesis of monophyly cannot be rejected. A phylogenetic taxonomy is proposed in which the Tropidurinae* is maintained as a metataxon (denoted with an asterisk), for which monophyly has not been demonstrated. Within the Phrynosomatinae, the close relationship of Sator and Sceloporus is questioned and an alternative hypothesis in which Sator is the sister taxon to a clade comprising Petrosaurus, Sceloporus, and Urosaurus is presented. Statistical tests of monophyly provide a powerful way to evaluate support for taxonomic groupings. Use of the metataxon prevents premature taxonomic rearrangements where support is lacking.
Food additives and contaminants. An update

Food additives continue to be a source of benefits to the consuming public but there are also perceived risks. Concern for the latter in the last decade has produced a society afflicted with cancer phobia. The intentional additives including sugars, salt, corn syrup, and dextrose make up 90% of the direct additives. These, along with a limited number of familiar items make up a large proportion of the remainder of the additives. Such common ingredients as nitrates and nitrites, solanine, cyanogenetic compounds, arsenic, etc., are unavoidably consumed in the diet and with little if any evidence for public health consequences. Major concern on the part of the public in recent years has been focused on man-made chemicals which are intentionally added to foods to enhance flavors and acceptability, nutrient value, shelf life and increased availability. These include food colors, nonnutritive and low-nutrient sweeteners, (saccharin, cyclamate, aspartame); antioxidants; and nitrites. Contaminants, sometimes incorrectly included in lists of food additives, present the greatest potential threat to public health. Such contaminants as mycotoxins, nitrosamines, polychlorinated biphenyls (PCBs), pesticides, among others, provide a continuing challenge to our regulatory agencies and to public health authorities. Evidence to date indicate that these responsible for food safety are doing an admirable job, and as a society, our food supply has never been better, or safer, and, as a population, we have never been healthier. Aside from contaminants, major concerns relate to an excess of good food and to obesity. These comments should not be taken to infer that we should relax our concern and surveillance; instead more concern and surveillance should be exerted toward those uncontrolled substances such as natural plant products and alleged natural nutrients, roots, herbs, etc., which are given much credit for positive health effects, without meeting the high standards of our legitimate food industry.
On Acyclic Orientations and Sequential Dynamical Systems

We study a class of discrete dynamical systems that consists of the following data: (a) a finite (labeled) graph Y with vertex set {1,...,n}, where each vertex has a binary state, (b) a vertex labeled multi-set of functions (F"i","Y: F"2^n->F"2^n)"i, and (c) a permutation @[email protected]?S"n. The function F"i","Y updates the binary state of vertex i as a function of the states of vertex i and its Y-neighbors and leaves the states of all other vertices fixed. The permutation @p represents a Y-vertex ordering according to which the functions F"i","Y are applied. By composing the functions F"i","Y in the order given by @p we obtain the sequential dynamical system (SDS):[F"Y,@p]=F"@p"("n")","[email protected][email protected]?F"@p"("1")","Y: F"2^n->F"2^n.In this paper we first establish a sharp, combinatorial upper bound on the number of non-equivalent SDSs for fixed graph Y and multi-set of functions (F"i","Y). Second, we analyze the structure of a certain class of fixed-point-free SDSs.
Biphasic decay of guide RNAs in Trypanosoma brucei.

Abstract Guide RNAs (gRNAs) are short mitochondrially encoded RNAs that contain the information for editing of messenger RNAs in Trypanosoma brucei . Although a great deal of work has focused on the utilization of gRNAs in editing, little is known about the turnover of gRNAs. In this report, we utilized in organello pulse chase and in vitro RNA decay experiments to directly examine gRNA turnover. We found that gRNAs are degraded by a biphasic mechanism. In the first step of decay, 3′ gRNA sequences encompassing primarily the post-transcriptionally added oligo(U) tail are rapidly removed. This is followed by a second step, which entails a comparatively slower degradation of the encoded gRNA body. Decay of the 3′ end of the gRNA is sequence specific, as it does not occur on oligoadenylated gRNAs. In contrast, the nucleotide composition of the 3′ extension does not affect the rate of degradation during the second, slower, decay step. Finally, competition assays suggest that complete gRNA decay is mediated by two distinct enzymes, one of which simultaneously recognizes elements of the oligo(U) tail and the encoded portion of the gRNA. Overall, these results provide the first evidence for a gRNA-specific decay pathway.
The Modernization of the American Stock Exchange 1971-1989

1. Highlights from Early Years 2. The Beginnings of Modernization 3. The National Market System 4. New Regimes, New Challenges 5. The Entrepreneurial Eighties on the Amex 6. The Great Plunge and its Aftermath
Temporal pattern of synthesis of the mouse cortical granule protein, p75, during oocyte growth and maturation

We previously demonstrated that a protein of M(r) 75,000 (p75) is localized to cortical granules (CGs) in mouse oocytes and eggs and is released upon activation or fertilization of eggs (K.E. Pierce, M. C. Siebert, G. S. Kopf, R. M. Schultz, and P. G. Calarco, 1990, Dev. Biol. 141, 381-392). To examine the temporal pattern of synthesis of p75 during the early stages of CG formation, growing oocytes, which were isolated from juvenile mice, were incubated for 4 hr in medium containing [35S]methionine, and radiolabeled proteins were immunoprecipitated using an antiserum that detects p75. Synthesis of p75 is detected at low levels in the smallest oocytes examined (less than 20 microns). Synthesis of p75 relative to total protein synthesis increases about 12-fold during oocyte growth from the 20-40 microns size and then remains constant throughout the remaining period of oocyte growth (40-70 microns). In the fully grown, germinal vesicle (GV)-intact oocyte (70-80 microns), immunoprecipitated p75 comprises approximately 1.5% of the total amount of radiolabeled protein. Three hours after the transfer of these oocytes to a medium that supports resumption of meiosis and GV breakdown in vitro, oocytes subjected to a 1-hr labeling pulse display a 35% decrease in the relative level of p75 synthesis. By 15 hr of maturation, p75 synthesis was reduced to 14% of that in the fully grown, GV-intact oocyte and this is similar to the level of p75 synthesis in ovulated eggs. The level of p75 synthesis following in vitro translation of total egg RNA is only 38% lower than that obtained from total oocyte RNA. In addition, synthesis of p75 is observed following in vitro translation of oocyte, but not egg, poly(A)+ RNA. These results are consistent with p75 synthesis during oocyte maturation being under translational control.
The Reversibility of Mitotic Exit in Vertebrate Cells

Cells proceed through the cell cycle in a highly ordered and unidirectional manner; however, if the degradation of cyclin B is prevented as cells exit mitosis and its associated Cdk1 kinase activity restored, cells can reverse back to M phase. A guiding hypothesis for cell-cycle regulation asserts that regulated proteolysis constrains the directionality of certain cell-cycle transitions1,2. Here we test this hypothesis for mitotic exit, which is regulated by degradation of the cyclin-dependent kinase 1 (Cdk1) activator, cyclin B3,4,5. Application of chemical Cdk1 inhibitors to cells in mitosis induces cytokinesis and other normal aspects of mitotic exit, including cyclin B degradation. However, chromatid segregation fails, resulting in entrapment of chromatin in the midbody. If cyclin B degradation is blocked with a proteasome inhibitor or by expression of non-degradable cyclin B, Cdk inhibitors will nonetheless induce mitotic exit and cytokinesis. However, if after mitotic exit, the Cdk1 inhibitor is washed free from cells in which cyclin B degradation is blocked, the cells can revert back to M phase. This reversal is characterized by chromosome recondensation, nuclear envelope breakdown, assembly of microtubules into a mitotic spindle, and in most cases, dissolution of the midbody, reopening of the cleavage furrow, and realignment of chromosomes at the metaphase plate. These findings demonstrate that proteasome-dependent degradation of cyclin B provides directionality for the M phase to G1 transition.
Evaluation of high-power solar electric propulsion using advanced Ion, Hall, MPD, and PIT thrusters for Lunar and Mars cargo missions,

This paper presents the results of mission analyses that expose the advantages and disadvantages of high-power (MWe-class) Solar Electric Propulsion (SEP) for Lunar and Mars Cargo missions that would support human exploration of the Moon and Mars. In these analyses, we consider SEP systems using advanced Ion thrusters (the Xenon [Xe] propellant Herakles), Hall thrusters (the Bismuth [Bi] propellant Very High Isp Thruster with Anode Layer [VHITAL], magnetoplasmadynamic (MPD) thrusters (the Lithium [Li] propellant Advanced Lithium-Fed, Applied-field Lorentz Force Accelerator (ALFA2), and pulsed inductive thruster (PIT) (the Ammonia [NH3] propellant Nuclear-PIT [NuPIT]). The analyses include comparison of the advanced-technology propulsion systems (VHITAL, ALFA2, and NuPIT) relative to state-of-theart Ion (Herakles) propulsion systems and quantify the unique benefits of the various technology options such as high power-per-thruster (and/or high power-per-thruster packaging volume), high specific impulse (Isp), high-efficiency, and tankage mass (e.g., low tankage mass due to the high density of bismuth propellant). This work is based on similar analyses for Nuclear Electric Propulsion (NEP) systems.
Ionic Permeability of the Guinea-pig Taenia Coli Muscle

WITHIN less than 2 yr, two diametrically conflicting views of the ionic permeability of the guinea-pig taenia coli muscle have been published in Nature1,2. The first1 assumed by analogy with frog skeletal muscle3–5 that the membrane is permeable to Cl. The intracellular Cl was then calculated from Donnan considerations and the values so obtained seemed to agree quite well with estimates based on electrophysiological measurements of inhibitory postsynaptic potentials. The second report2 does not refer to the first, but it confirms still earlier data6 on the “anomalous” osmotic behaviour of taenia coli muscles. The muscles do not gain weight on prolonged exposure to isosmotic KCl-enriched media. They lose weight when exposed to media that are made hyperosmotic by addition of KCl.
Renormalization and scaling behavior of non-Abelian gauge fields in curved spacetime

Abstract In this article we discuss the one loop renormalization and scaling behavior of non-Abelian gauge field theories in a general curved spacetime. A generating functional is constructed which forms the basis for both the perturbation expansion and the Ward identities. Local momentum space representations for the vector and ghost particles are developed and used to extract the divergent parts of Feynman integrals. The one loop diagram for the ghost propagator and the vector-ghost vertex are shown to have no divergences not present in Minkowski space. The Ward identities insure that this is true for the vector propagator as well. It is shown that the above renormalizations render the three- and four-vector vertices finite. Finally, a renormalization group equation valid in curved spacetimes is derived. Its solution is given and the theory is shown to be asymptotically free as in Minkowski space.
EFFECTS OF SAVANNA RESTORATION ON THE FORAGING ECOLOGY OF INSECTIVOROUS SONGBIRDS

Abstract We studied the foraging behavior of insectivorous songbirds during the breeding season at four sites in Illinois, each with restored open-canopy savanna habitat (65% mean canopy closure) and closed-canopy forests (89% mean canopy closure). We sampled and compared apparent tree species preference, foliage layer preference, and proportional use of different prey-attack maneuvers in the two habitats. In closed-canopy forests, three of nine songbird species foraged in black oak (Quercus velutina) and white oak (Q. alba) more than expected based on availability, and foraged less than expected in shade-tolerant trees such as sugar maple (Acer saccharum) and red elm (Ulmus rubra). Four species also displayed apparent preferences for black locust (Robinia pseudoacacia) and hackberry (Celtis occidentalis). In contrast, songbirds used tree species according to availability in open-canopy habitat. We observed apparent preferences for the shrub and subcanopy vegetation layers (0–5 m and 6–10 m) in open-canop...
Altered expression of miR-24, miR-126 and miR-365 does not affect viability of childhood TCF3 -rearranged leukemia cells

Among the microRNAs (miRNAs) that control different cellular processes, miR-24, miR-126 and miR-365 were shown to regulate cell cycle progression and apoptosis in various types of tumors. Interestingly, these three miRNAs were downregulated in pediatric TCF3-rearranged B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Here, we showed that individual or combined overexpression of miR-24, miR-126 and miR-365 can neither alter the cell cycle progression nor the amount of apoptosis in 697, KASUMI-2 or MHH-CALL-3 TCF3-rearranged leukemic cells. We further integrated the miRNA-mRNA expression data of 37 children with BCP-ALL to identify candidate target genes for these three miRNAs. However, the expression levels of selected candidate target genes (ELL, EBF3 and IRF4 for miR-24, PITPNC1 for miR-126 and ZAP-70 for miR-365) did not reduce upon miRNAs overexpression in MHH-CALL-3 TCF3-rearranged leukemic cells. Although the expression level of AURKB-a validated target for miR-24-was reduced upon miR-24 overexpression in hepatocarcinoma HEP-G2 cells, overexpression of miR-24 cannot alter AURKB expression levels in MHH-CALL-3 TCF3-rearranged leukemic cells. Taken together, our data suggest that miRNAs' function is highly tissue-dependent and that a defined biological target gene or function of one miRNA in a specific tissue cannot be extended as a generalized target/function for that miRNA in all types of cells/tissues.
Contemporary Asymmetric Conflict Theory in Historical Perspective

This article offers an intellectual history of theoretical work devoted to explaining asymmetric conflict outcomes since World War II. Three factors are critical to understanding how the literature has evolved. First, the concept of “asymmetric conflict” encompasses a number of overlapping literatures, including insurgency, terrorism, counterinsurgency, and most recently, civil wars. Second, and interrelated, the field of inquiry has been unproductively divided between military and academic thinkers, with insufficient engagement between the two communities. Third, the popularity of the field of inquiry following the events of September 11, 2001, and the subsequent American-led military operations in Afghanistan (2001) and Iraq (2003) have resulted in analyses that are empirically rich, but have provided little in the way of theoretical advances. The conclusion offers an overall assessment of the field of inquiry into asymmetric conflict outcomes, suggested directions for future research, and a table of ma...
Chaparral-induced hepatotoxicity

Abstract Background: Chaparral leaf (Larrea tridentata) has been used for centuries to treat a variety of ailments. Laboratory investigations have demonstrated the presence of at least one pharmacologically active lignan, but no controlled studies have demonstrated efficacy and safety in vivo. Recent reports suggest chaparral may cause toxic hepatitis in some chronic users. Case Report: A 27-year-old Hispanic male developed hepatitis approximately 12 months after beginning therapy with chaparral capsules. Liver biopsy showed hepatocellular injury with necrosis and periportal inflammation. Liver function stabilized 6 weeks after hepatitis was first recognized. Conclusions: Although chaparral has been associated with cholangitis, impaired synthetic function and fulminant hepatic failure, because the pattern of chaparral use is unknown, the incidence of hepatotoxicity is also unknown. Severe liver damage may be more common in patients taking higher doses for longer periods of time. Prolonged courses of chaparral should not be recommended routinely. Patients desiring to use chaparral for periods greater than two weeks should be warned of the potential for hepatotoxicity and monitored closely.
Cycling cross-bridges increase myocardial stiffness at submaximal levels of Ca2+ activation.

Permeabilized multicellular preparations of canine myocardium were subjected to controlled length changes to investigate the extent to which cross-bridges augment passive stiffness components in myocardium at low levels of Ca2+ activation. When the preparations were immersed in pCa 9.0 solution (negligible free [Ca2+]) they behaved as simple elastic systems (i.e., tension increased proportionately with length). In contrast, when the muscles were stretched in Ca2+ activating solutions, tension rose much more rapidly during the initial phase of the movement than thereafter. Several lines of evidence suggest that the nonlinear response represents the displacement of populations of cycling cross-bridges that are perturbed by interfilamentary movement and take some time to recover. 1), The stiffness of the initial phase increased proportionately with the level of Ca2+ activation. 2), The magnitude of the short-range response increased with stretch velocity. 3), The initial response was reversibly reduced by 5-mM 2,3-butanedione monoxime, a known cross-bridge inhibitor. The initial stiffness of the passive elastic (pCa 9.0) response was equivalent to the Ca2+ dependent component at 2% (pCa ∼ 6.2) of the maximal (pCa 4.5) level. These results suggest that cross-bridges may significantly affect diastolic chamber stiffness.
Teaching Anthropology Courses through a Human Rights Lens

: [public affairs, human rights forum, human right] Gretchen E Schafft is contributing editor of Human Rights Forum, the AN column of the AAA Committee for Human Rights.
IMMUNOHISTOCHEMICAL EXPRESSION OF ENDOTHELIAL NITRIC OXIDE SYNTHASE AND C-KIT IN THE PLACENTA OF COMPLETE HYDATIDIFORM MOLE

Complete hydatidiform mole is an abnormal conceptus characterized by hydropic villi accompanied by proliferating trophoblasts. Its pathogenesis is largely unknown. Endothelial nitric oxide synthase is induced by vascular endothelial growth factor and has been implicated in the pathogenesis of preeclampsia and other physiologic conditions in the placenta. C-kit is the tyrosine kinase receptor and is involved in tumor formation elsewhere in the body. Using standard immunohistochemical protocols, we studied the expression of C-kit and endothelial nitric oxide synthase in the placenta of 10 patients with complete hydatidiform mole. Cytoplasmic and nuclear staining with endothelial nitric oxide synthase was identified in the cytotrophoblast and intermediate trophoblast layers in all cases, with high staining in 7/10 and 6/8 cases, respectively. Minimal staining is identified in the syncytiotrophoblast layer. Hofbauer stromal cells were identified in 9 cases and showed low staining intensity in 7/9 cases. Cytop...
Antioxidant effects of conjugated linoleic acid isomers in isolated human low-density lipoproteins

The possible beneficial health effects of conjugated linoleic acid (CLA) have been the subject of extensive investigation. The antioxidant capacity of CLA is one possible action to explain its protective effect in cancer and atherosclerosis. The objective of this study was to assess, through enrichment of human low-density lipoproteins (LDLs) with CLA isomers, the antioxidant and pro-oxidant properties of CLA isomers (9-cis, 11-trans-CLA; 9-trans, 11-trans-CLA; 9-cis, 11-cis-CLA; and 10-trans, 12-cis-CLA) and to determine at what concentrations the effects are most prominent. Lipid oxidation of human LDL was determined by the thiobarbituric acid reactive substances assay. In all isomers tested, the enrichment with CLA at 2 μmol/L resulted in a pro-oxidant response when compared to LDL not enriched with CLA. Reduced lipid peroxidation was observed at the middle enrichment levels for each isomer, suggesting a promotion-inhibition-promotion action of CLA, perhaps reflecting biphasic effects consistent with the phenomenon defined as hormesis. In general, enrichment of isolated human LDL with CLA isomers promoted oxidation.
Nickel hyperaccumulation in Thlaspi goesingense: A scientific travelogue

During the past 6 years, my research group has been trying to unravel the molecular genetic basis of nickel hyperaccumulation in Thlaspi. Our long-term goal is to use the genes we identify to genetically engineer plants ideally suited for phytoremediation (Salt et al., 1998), This investigation has taken us on a journey with many twists, turns, dead ends, and through many types of terrains in the plant physiology landscape. In this short essay, I would like to retrace for you this journey, providing a glimpse of what we feel is now appearing as the essential components of how certain plants hyperaccumulate Ni.
An analysis of the efficacy and efficiency of hierarchical procedures for computing trajectories over complex surfaces

Abstract A set of hierarchically-organized, heuristic path-finding procedures were applied to two subareas of a complex surface. These procedures typically found paths that were very close to optimal in terms of satisfying a minimum integral constraint. The procedures were one to two orders of magnitude less costly to apply than a set of similar, non-hierarchical procedures that found optimal paths. A systematic evaluation of hierarchical procedures having varying topologies and heuristic guidance functions, and employing different surface representations, was made. No procedure examined minimized both path traversal and path computation costs, and the choice of a best procedure was found to depend significantly on the nature of the surface traversed.
Demonstration of retroviral proteins associated with erythroid progenitors of cats with feline leukemia virus-induced erythroid aplasia

Feline erythroid aplasia is a fatal retrovirus-induced disease related to infection with feline leukemia virus of subgroup C. When bone marrow cells from cats inoculated with FeLV were incubated with polyvalent antibody to FeLV and cultured for erythroid colony formation, a complement-dependent inhibition of erythroid progenitors was demonstrated with virtually complete suppression of erythroid colony-forming units (CFU-E) and burst-forming units (BFU-E) evident from post-inoculation week 4 until termination in cats with progressive infection. When bone marrow cells from cats with regressive infection were treated similarly, CFU-E were inhibited on post-inoculation week 4 (98% inhibition) when the cats were viremic, and on week 6 (77% inhibition) when the leukocytes were negative for FeLV by immunofluorescence. These data suggest that the retroviral proteins are associated with erythroid progenitors or critical accessory cells and may play a role in selective suppression of erythropoiesis.
Studies on the Biochemistry and Fine Structure of Silica Shell Formation in Diatoms. Photosynthesis and Respiration in Silicon-Starvation Synchrony of Navicula pelliculosa

Rates of photosynthesis, measured by oxygen electrode or by 14CO2 fixation, dark respiration and 32P-phosphate incorporation are reported for the silicon-starvation synchrony of the fresh water diatom Navicula pelliculosa. During late exponential growth the rates were consistent with increase in carbon mass. During silicon starvation, rates of carbon dioxide fixation, oxygen evolution and 32P incorporation fell, and the saturating light intensity decreased from 27,000 lux to 5000 lux. Reintroduction of silicon led to immediate transients in all parameters studied, followed by a prolonged increase in rate of dark respiration and a gradual increase in apparent photosynthesis. During release of daughter cells, the rates of dark respiration decreased as photosynthesis and 32P incorporation increased. These results are discussed in relation to effects of silicon on the energy metabolism of the diatom.
Fission fragment ionization (252Cf) mass spectrometry. Positive and negative spectra and decomposition mechanisms for seven compounds

Abstract The 252Cf fission fragment ionization mass spectra (both positive and negative ions) have been determined for alanine, arginine, sucrose, guanosine, 5′-adenosine monophosphate alanylalanylalanine, and lysyltyrosylthreonine. The lower m/z limit is 18 for the positive and 26 for the negative spectra tabulated. Mass to ion charge values are given with millimass precision, which permits deduction of atomic compositions for many of the observed ions. Reasonable mechanisms for the production of some of these ions are postulated. The significant findings of the study are: 1. (1) The amount of fragmentation occurring is large both in that quasi-molecular ion intensities are low and that many small ions are produced with large intensities. For example, only for alanine is the intensity of the quasi-molecular ion greater than 10% of the total ionization, and for arginine the CN− ion comprises 56% of the total negative ionization. 2. (2) The spectra observed have characteristically a quasi-molecular ion, a large gap without ions, and many ions at low mass. 3. (3) Detectable amounts of quasi-molecular ions are present in all the spectra. 4. (4) Reactions invoking known chemistry of gaseous positive and negative ions can be written for the formation of many of the fragment ions. 5. (5) The results indicate that the ionization process occurring is primarily a relatively high-energy one since it produces much fragmentation, but it has a low-energy component which is involved in the formation of the quasi-molecular ions observed here and in previosly published work. An ancillary finding is that the fission fragment ionization method seems to have a high sensitivity for producing anions from certain inorganic trace impurities.
Consideration of stimulated Raman scattering in Yb:Sr 5 (PO 4 ) 3 F laser amplifiers

The stimulated Raman-scattering (SRS) gain coefficient has been measured quantitatively for the first time to our knowledge in Yb:Sr5(PO4)3F to be 1.23 ± 0.12 cm/GW at 1053 nm. These data, along with surface and bulk losses, feedback that is due to surface reflections, gain saturation, and bandwidth, have been applied to a quantitative model that predicts the effects of SRS within a laser amplifier system where the laser gain media show SRS gain. Limitations and impact to the laser amplifier performance are discussed, along with possible techniques to reduce SRS loss.
The physical properties of the chloromycetin particles.

When cells of E. coli B are incubated in Chloromycetin (CM), ribonucleoprotein particles containing 75% ribonucleic acid and 25% protein are observed. These chloromycetin particles (CM particles), though unstable in high salt concentrations, do not degrade in solvents with low counter ion concentrations. There are two CM particles with sedimentation coefficients of 18 s and 25 s. When the counter ion concentration is increased, the sedimentation coefficient of the CM particles increases while the intrinsic viscosity decreases. This observation suggests that the CM particles are loosely coiled polyelectrolytes. Thus, their physical properties resemble those of ribonucleic acid rather than the ribosomes. The CM particle fraction contains the 16 s and 23 s ribonucleic acid components which are found in the normal ribosomes. The data are consistent with the conclusion that the 18 s CM particle contains the 16 s ribonucleic acid, while the 25 s CM particle contains 23 s ribonucleic acid.
Dietary exposures to selected metals and pesticides.

Average daily dietary exposures to 11 contaminants were estimated for approximately 120,000 U.S. adults by combining data on annual diet, as measured by a food frequency questionnaire, with contami...
Satellite measurements of large-scale air pollution - Measurements of forest fire smoke

The transport, optical properties, total mass, and removal of smoke produced by forest fires in western Canada during late July and early August 1982 are studied using NOAA 7 AVHRR data. Color composite imagery is produced to track the movement of the smoke over Canada and the U.S. as the smoke traveled thousands of km from the source region. Smoke optical thickness, particle size, and single scattering albedo are computed using radiances measured by AVHRR bands 1 and 2. Results show that smoke optical thickness ranged from less that 0.1 to greater than 3.7 and the geometric mean mass radii ranged from 300 to 900 nm. The smoke single scattering albedo ranged from 0.9 to nearly 1.0. The total smoke mass over the eastern U.S. ranged from 0.1 to 0.5 Tg, which is close to the 0.5 Tg estimated from the forest fuel content. The smoke lifetime is estimated to be between 15 and 20 days.
A Study of Work-Family Conflict Among IT Professionals: Job Characteristics, Individual Values, and Management Practices

In this study, we develop a model that explains the work-family conflict experienced by IT professionals. We propose two major sources of work-family conflict: the structure of work and individual mindsets toward work. Furthermore, we examine beliefs about the employer that can diminish work-family conflict. We test our hypotheses using data gathered from 126 IT professionals. Our model explains more than 45% of the variance in work-family conflict. Our findings suggest: (1) skill variety requirements increase work-family conflict, (2) work ethic positively relates to work-family conflict, (3) leisure ethic negatively relates to work-family conflict, and (4) professionalism has mixed effects on work-family conflict. Finally, we found that when IT professionals perceive high levels of job security and are satisfied with supervision, work-family conflict diminishes. The study concludes with implications for research and practice.
Impact of a Short Pre-Freshman Program on Retention

The Biology Intensive Orientation for Students (BIOS) Program at Louisiana State University was designed to increase the success of incoming freshman biology majors in the first course in their major. The program combined content lectures and examinations for BIOL 1201–Introductory Biology for Science Majors, the first course in their major, as well as learning styles assessments and informational sessions intended to provide the students with a preview of the requirements of biology, and the pace of college. BIOS participants showed increased success and retention in the biology major, and remained on track to graduate in 4 years at a significantly higher rate than students who did not participate in BIOS.
On the shielding effect of the Helmholtz equation

Hadamard-type instability has been known for over a century as a cause of ill-posedness of the Cauchy problem for elliptic PDEs. This ill-posedness manifests itself as evanescent modes growing exponentially when propagated in the reverse direction. Since every oscillating mode of the Laplace equation is evanescent, the ill-posedness of its Cauchy problem is solely due to Hadamard-type instability. The presence of the propagating modes and beams for the Helmholtz equation gives rise to an entirely different type of ill-posedness, hitherto unknown to the practice, and untreated by the theory, of inverse scattering. We will present this fundamental phenomenon of ill-posedness for the Helmholtz equation. © 2007 Wiley Periodicals, Inc.
Optimal scaling factors for CM1 and CM3 atomic charges in RM1-based aqueous simulations

Scaling factors for atomic charges derived from the RM1 semiempirical quantum mechanical wavefunction in conjunction with CM1 and CM3 charge models have been optimized by minimizing errors in absolute free energies of hydration, ΔG(hyd) , for a set of 40 molecules. Monte Carlo statistical mechanics simulations and free energy perturbation theory were used to annihilate the solutes in gas and in a box of TIP4P water molecules. Lennard-Jones parameters from the optimized potentials for liquid simulations-all atom (OPLS-AA) force field were utilized for the organic compounds. Optimal charge scaling factors have been determined as 1.11 and 1.14 for the CM1R and CM3R methods, respectively, and the corresponding unsigned average errors in ΔG(hyd) relative to experiment were 2.05 and 1.89 kcal/mol. Computed errors in aniline and two derivatives were particularly large for RM1 and their removal from the data set lowered the overall errors to 1.61 and 1.75 kcal/mol for CM1R and CM3R. Comparisons are made to the AM1 method which yielded total errors in ΔG(hyd) of 1.50 and 1.64 kcal/mol for CM1A*1.14 and CM3A*1.15, respectively. This work is motivated by the need for a highly efficient yet accurate quantum mechanical (QM) method to study condensed-phase and enzymatic chemical reactions via mixed QM and molecular mechanical (QM/MM) simulations. As an initial test, the Menshutkin reaction between NH(3) and CH(3) Cl in water was computed using a RM1/TIP4P-Ew/CM3R procedure and the resultant ΔG(‡) , ΔG(rxn) , and geometries were in reasonable accord with other computational methods; however, some potentially serious shortcomings in RM1 are discussed.
Performance enhancement of distributed parameter systems by a class of nonlinear controls

In this paper a class of nonlinear control structures is proposed to address the phenomenon of energy exchange between certain controlled modes and uncontrolled modes in the control of distributed parameter systems. The control structure is derived by requiring the energy in the controlled modes to be dissipated in a finite time.
Shared simple virtual environment: an object-oriented framework for highly interactive group collaboration

Shared simple virtual environment (SSVE) is an object-oriented software framework designed for object-focused small group collaboration in highly dynamic virtual environments. Compared to most other collaborative virtual environment systems, SSVE allows a team of six to eight people to collaborate closely on a highly interactive model construction task. SSVE is a "multi-multi" framework - multi-user, multi-threaded, multi-platform, and multi-modal. Numerous interaction, awareness and collaboration mechanisms are provided by the framework and by applications that use the framework, including "what you see is what I see," deictic references, and exclusive object access. Several concurrency control mechanisms are also supported through the framework, including those suitable for closely-coupled synchronous collaboration in highly dynamic virtual worlds. In addition, support is provided for emergent group collaboration modes, and a novel user interface widget, the collaboration tree, is introduced to facilitate subgroup formation and integration of task results. In short, SSVE is a framework for the development of applications which explore group collaboration mechanisms in highly-interactive shared virtual environments. A small pilot study that used the framework to validate the utility and stability of the framework, as well as to investigate larger issues of group collaboration, is also presented.
Cell Therapy for Models of Pain and Traumatic Brain Injury

This chapter reviews the cell transplantation strategies that have been explored as potential options in the treatment of pain and traumatic brain injury (TBI). As the goals of these two therapeutic targets are widely disparate, approaches have evolved along distinctive paths. Thus, although the provision of a local cellular source of pharmacologic analgesic molecules may be most appropriate in the management of chronic pain, central nervous system (CNS) repair after traumatic injury will most likely require replacement of lost neural populations and reestablishment of appropriate neurocircuitry to be maximally effective. The development of cellular strategies that would replace, or be used as, an adjunct to current clinical treatments for neuropathic pain have progressed over the past 30 yr. There are a variety of useful surgical and pharmacologic interventions, including electric stimulation, implantable mechanical pumps, and a myriad of drugs for pain relief, but cell and molecular technologies are a new frontier in pain medicine.