cssi/SciSciGPT-SciSciNet huggingface dataset:
Examining a Transition from Supramolecular Halogen Bonding to Covalent Bonds: Topological Analysis of Electron Densities and Energies in the Complexes of Bromosubstituted Electrophiles.

The transition from weak (noncovalent) interactions to fully developed covalent bonds is examined using the quantum theory of atoms in molecules in a series of halogen-bonded (XB) complexes of bromosubstituted electrophiles, RBr, with 1,4-diazabicyclo[2.2.2]octane (DABCO) and Cl- and Br- anions. The gradual decrease in the XB lengths in these associations, dBr···Y (where Y = Cl-, Br-, or N), was accompanied by the exponential increase in the binding energies and charge transfer, as well as electron densities and magnitudes of the kinetic and potential energy densities at the bond critical points (BCPs) on the Br···Y bond path. These indices, as well as characteristics of the adjacent bonds in the XB donor, followed remarkably close trend lines when plotted against the normalized XB length RBrY = dBr···Y/(rBr + rY) (where rBr and rY are the van der Waals radii) regardless of the methods [MP2/6-311+G(d,p) or M062X/6-311+G(d,p)], media (gas phase or dichloromethane), and nucleophiles (Cl-, Br-, or DABCO). In the systems with an RBrY higher than about 0.78, the energy densities H(r) at BCPs at the Br···Y bond path were small and positive, and XBs did not substantially affect the characteristics of the adjacent R-Br covalent bond in the XB donor. Accordingly, the XB can be identified as noncovalent in this range. In the complexes with RBrY values between about 0.67 and 0.78, energy densities H(r) at Br···Y BCPs were negative, and their magnitudes increased with the decrease in the Br···Y separation. In this range, formation of XBs was accompanied by the increase in the R-Br bond length in the XB donor and the decrease in the magnitude of the (negative) H(r) values at the BCPs of the R-Br bonds. XBs can be classified as partially covalent in this RBrY range. At an RBrY less than about 0.67, electron densities were larger, and energy densities were more negative at BCPs of the Br···Y bond than those at BCPs of the R-Br bond in the XB donor. This indicates that Br···Y bonds were stronger than R-Br bonds, and these (Br···Y) XBs can be regarded as essentially covalent. The synchronous change of a variety of (R-Br and Br···Y) bonding characteristics with RBrY suggests that the normalized XB bond length can be used as a basic parameter in the identification of the type of intermolecular interaction. A continuity of these characteristics suggests an inherent relationship between limiting (covalent and noncovalent) types of XBs and thus an onset of molecular-orbital interactions in the weaker bonds.
Satellite Cell Expression of RAGE (Receptor for Advanced Glycation end Products) Is Important for Collateral Vessel Formation

Background The growth and remodeling of vascular networks is an important component of the prognosis for patients with peripheral artery disease. One protein that has been previously implicated to play a role in this process is RAGE (receptor for advanced glycation end products). This study sought to determine the cellular source of RAGE in the ischemic hind limb and the role of RAGE signaling in this cell type. Methods and Results Using a hind limb ischemia model of vascular growth, this study found skeletal muscle satellite cells to be a novel major cellular source of RAGE in ischemic tissue by both staining and cellular sorting. Although wild-type satellite cells increased tumor necrosis factor-α and monocyte chemoattractant protein-1 production in response to ischemia in vivo and a RAGE ligand in vitro, satellite cells from RAGE knockout mice lacked the increase in cytokine production both in vivo in response to ischemia and in vitro after stimuli with the RAGE ligand high-mobility group box 1. Furthermore, encapsulated wild-type satellite cells improved perfusion after hind limb ischemia surgery by both perfusion staining and vessel quantification, but RAGE knockout satellite cells provided no improvement over empty capsules. Conclusions Thus, RAGE expression and signaling in satellite cells is crucial for their response to stimuli and angiogenic and arteriogenic functions.
Pathway-focused genetic evaluation of immune and inflammation related genes with chronic fatigue syndrome

Abstract Recent evidence suggests immune and inflammatory alterations are important in chronic fatigue syndrome (CFS). This study was done to explore the association of functionally important genetic variants in inflammation and immune pathways with CFS. Peripheral blood DNA was isolated from 50 CFS and 121 non-fatigued (NF) control participants in a population-based study. Genotyping was performed with the Affymetrix Immune and Inflammation Chip that covers 11 K single nucleotide polymorphisms (SNPs) following the manufacturer’s protocol. Genotyping accuracy for specific genes was validated by pyrosequencing. Golden Helix SVS software was used for genetic analysis. SNP functional annotation was done using SPOT and GenomePipe programs. CFS was associated with 32 functionally important SNPs: 11 missense variants, 4 synonymous variants, 11 untranslated regulatory region (UTR) variants and 6 intronic variants. Some of these SNPs were in genes within pathways related to complement cascade (SERPINA5, CFB, CFH, MASP1 and C6), chemokines (CXCL16, CCR4, CCL27), cytokine signaling (IL18, IL17B, IL2RB), and toll-like receptor signaling (TIRAP, IRAK4). Of particular interest is association of CFS with two missense variants in genes of complement activation, rs4151667 (L9H) in CFB and rs1061170 (Y402H) in CFH. A 5′ UTR polymorphism (rs11214105) in IL18 also associated with physical fatigue, body pain and score for CFS case defining symptoms. This study identified new associations of CFS with genetic variants in pathways including complement activation providing additional support for altered innate immune response in CFS. Additional studies are needed to validate the findings of this exploratory study.
Structure of Matter

The existence of the universe is explained by two entities: matter and energy. These two entities are interchangeable and exist in different forms to make up all things visible or invisible in the universe. Whereas matter has a definite size, shape, and form, energy has different forms but no size and shape.
Probability distribution of drug-resistant mutants in unselected populations of Mycobacterium tuberculosis.

The fluctuation test shows that Mycobacterium tuberculosis mutates to resistance to isoniazid, streptomycin, ethambutol and rifampin spontaneously and at random. The average mutation rates for the drugs, in the same order, were calculated to be 2.56 × 10−8, 2.95 × 10−8, 10−7, and 2.25 × 10−10 mutation per bacterium per generation. The relatively high mutation rate to ethambutol resistance and the low mutation rate to rifampin resistance were confirmed by analyzing the increase in the proportion of mutants with time in a growing population of the tubercle bacilli. The highest proportions of mutants to be expected in unselected populations of the tubercle bacilli were calculated from the results of fluctuation tests.
Quantifying Inhomogeneous, Instantaneous, Irreversible Transport Using Passive Tracer Field as a Coordinate

Long-lived chemicals in the atmosphere and ocean often reveal surprisingly inhomogeneous distributions, contrary to the intuition that mixing homogenizes them. This is because mixing itself is inhomogeneous: coherent structures in the flow separate regions of fast mixing with semipermeable barriers to transport, and concentrated gradients tend to be found in the latter. The fluxes of materials across the barrier region are of particular interest, since that region is an interface between two fluid masses with distinct chemical characteristics. Yet these fluxes are difficult to measure because the barrier shape is often unsteady and irregular. With spatially fixed (Eulerian) coordinates, it is easy to confuse reversible undulation of the barrier with true, irreversible exchange of matter across it. Particle tracking methods, on the other hand, do not give useful flux–gradient relationships. Given these and other problems with the traditional formalisms, we will advocate a different diagnostic approach to mixing, utilizing a passive tracer field under advection and diffusion. We demarcate a mass of fluid by the isosurfaces of the tracer and ask how much mass is being exchanged through these surfaces. This essentially reduces the problem to 1D mass transport in the tracer coordinate. The purpose of this chapter is to demonstrate how this formalism helps understand the synergy between deformation and diffusion that enhances mixing, quantify inhomogeneous structure of mixing (such as barriers), and extract the instantaneous, irreversible part of transport. We will also touch on the techniques for partitioning fluxes into two opposing directions (and hence quantifying asymmetry in transport) and discuss the present diagnostic in relation to the Eulerian eddy diffusivity and to the probability density function (PDF).
Studies of Boron Implantation Through Photochemically Deposited SiO2 Films on Hg1-xCdxTe

Variable temperature Hall and resistivity measurements have been used to monitor the changes in carrier behavior in p-type Hg1-xCdxTe when boron ions are implanted through photochemically deposited SiO2. The formation of an n-type layer is demonstrated. Quantitative and non-destructive determinations of the absolute 10B concentration and distribution has been obtained by the novel method of neutron depth profiling. As expected, the boron distributions in the SiO2 films and Hg1-xCdxTe are strongly dependent upon the ion implant energy. However, negligible changes in the boron depth profiles were found after 200°C anneals. The present results are briefly related to the performance behavior of mid-wavelength infrared (MWIR) sensors produced via generic ion implantation procedures.
Nuclear Power Facilities, Safety

Safety has played a dominant role in the ability to generate electricity by nuclear means because large quantities of highly radioactive fission products are generated with the energy from fission. Strict control is maintained over these radioactive materials to assure that public and worker health and safety are protected. The basic safety principles, defense-in-depth design philosophy, and key safety design features which apply to all nuclear facilities are discussed. Specific examples are given from nuclear power plant design. The methods of assessment of safety are described, both for self-assessment and independent assessment. The roles of industry and government in the assessment process are outlined. Comparative risks of nuclear power are substantially lower than most other methods of generating electricity. The specific safety characteristics of the nuclear power plant that generates the electricity, and of the nuclear fuel cycle, which functions to produce nuclear fuel and dispose of radioactive wastes are each given. Special focus is placed on the safe disposal of spent fuel and radioactive waste. The basic radiation exposure and health standards which establish the foundation of public and worker protection are cited. The safety of future nuclear power plants is summarized. Keywords: Basic safetyn; Design; Assessment; Risks; Safety characteristics; Nuclear power plants; Nuclear fuel cycle. Spent fuel; Radioactive waste; Radiation exposure; Safety principles
What Do Nuclear Weapons Offer States? A Theory of State Foreign Policy Response to Nuclear Acquisition

How do nuclear weapons change the foreign policies of the states that acquire them? This paper offers a theory, labeled “nuclear pragmatism,” that explains the origins of six foreign policy behaviors that nuclear acquisition may facilitate — aggression, expansion, independence, bolstering, steadfastness, and compromise. While nuclear weapons may facilitate each of these behaviors, different states have different goals in international politics, and different combinations of behaviors are thus attractive to different states. The theory argues that three independent variables are important in determining which of these behaviors states are likely to use nuclear acquisition to facilitate, and thus condition the effect of nuclear acquisition. These variables are (1) the presence of severe territorial threats or an ongoing war with a peer competitor; (2) the presence of allies that provide for the state’s security; and (3) whether the state is increasing in power relative to its primary rivals. I illustrate the theory with empirical examples of the different theoretical pathways identified, and make predictions for the changes in foreign policy that should be expected if Iran were to acquire nuclear weapons.
Analysis of Active Site Residues of Botulinum Neurotoxin E by Mutational, Functional, and Structural Studies: Glu335Gln Is an Apoenzyme†

Clostridial neurotoxins comprising the seven serotypes of botulinum neurotoxins and tetanus neurotoxin are the most potent toxins known to humans. Their potency coupled with their specificity and selectivity underscores the importance in understanding their mechanism of action in order to develop a strategy for designing counter measures against them. To develop an effective vaccine against the toxin, it is imperative to achieve an inactive form of the protein which preserves the overall conformation and immunogenicity. Inactive mutants can be achieved either by targeting active site residues or by modifying the surface charges farther away from the active site. The latter affects the long-range forces such as electrostatic potentials in a subtle way without disturbing the structural integrity of the toxin causing some drastic changes in the activity/environment. Here we report structural and biochemical analysis on several mutations on Clostridium botulinum neurotoxin type E light chain with at least two producing dramatic effects: Glu335Gln causes the toxin to transform into a persistent apoenzyme devoid of zinc, and Tyr350Ala has no hydrolytic activity. The structural analysis of several mutants has led to a better understanding of the catalytic mechanism of this family of proteins. The residues forming the S1' subsite have been identified by comparing this structure with a thermolysin-inhibitor complex structure.
Finding Passion in Teaching and Learning: Embedding Literacy Skills in Content-Rich Curriculum

This study describes a collaboration between the American Museum of Natural History and the Bank Street College Reading and Literacy Program. The collaboration is a response to mandated curriculum that emphasizes instruction in basic skills at the expense of content knowledge acquisition. It is designed to demonstrate ways of embedding instruction in the basic skills of reading and writing into the content of science and social studies curriculum. Participants in the collaboration report that they have gained a deeper understanding of theoretical concepts, learned how to embed skills instruction into meaning-rich curriculum, and come to understand importance of curriculum and instruction that build on children's knowledge and interests, their language strengths, and their curiosity.
A computer program for predicting protein antigenic determinants

A computerized method for predicting the locations of protein antigenic determinants is presented, which requires only the amino acid sequence of a protein, and no other information. This procedure has been used to predict the major antigenic determinant of the hepatitis B surface antigen, as well as antigenic sites on a series of test proteins of known antigenic structure [Hopp & Woods (1981) Proc. natn. Acad. Sci. U.S.A. 78, 3824-3828.] The method is suitable for use in smaller personal computers, and is written in the BASIC language, in order to make it available to investigators with limited computer experience and/or resources. A means of locating multiple antigenic sites on a homologous series of proteins is demonstrated using the influenza hemagglutinin as an example.
Effects of campus foodservice attributes on perceived value, satisfaction, and consumer attitude: A gender-difference approach

Abstract This study explores a conceptual framework incorporating interrelationships among campus foodservice attributes, perceived value, satisfaction, and effects of these on consumer attitude. Mediating roles of perceived value and satisfaction as well as gender differences in attitude formation process also are investigated within the conceptual framework. Results confirm that enhanced performance in service and product quality, menu, and facility have favorable effects on perceived value, satisfaction and, ultimately, on consumer attitude. However, the attitude-formation process and mediating roles of perceived value and satisfaction differ notably between male and female consumers.
Regulation of ferritin genes and protein

Increasingly, perturbations in cellular iron and ferritin are emerging as an important element in the pathogenesis of disease. These changes in ferritin are important not only in the classic diseases of iron acquisition, transport, and storage, such as primary hemochromatosis, but also in diseases
The heat of combustion and strain energy of 2,2-paracyclophane

Abstract The heat of combustion and vapor pressure curve of solid 2,2-paracyclophane have been determined and used to derive the heats of combustion and formation of both the solid and gaseous compound. Comparison of the experimental heat of formation with that expected for an unstrained reference structure indicates a strain energy of 31 kcal mole −1 . The division of the strain energy among several contributions is discussed.
Conformational dynamics of the dimethyl phosphate anion in solution

Abstract The conformational dynamics of the DNA phosphodiester linkage in solution is modeled by performing first principles molecular dynamics simulations of the dimethyl phosphate anion ((CH 3 O) 2 PO 2 − or DMP − ) in water, in the presence of a sodium cation. We observe conformational changes in DMP − in solution, which are related to the approach of the sodium cation to the anionic oxygens of DMP − . These simulations demonstrate that the presence of a counterion may play a significant role in driving the transition between different conformers of DMP − .
Communicatory Effect of Body Position in Pagurus Bernhardus (L.) (Decapoda, Anomura) 1)

Pagurus bernhardus kommuniziert durch optische Signale. Ausser den speziellen aggressiv wirkenden Bewegungen der Chelipeden und Laufbeine wurden Korperhaltungen durch Modelldarbietungen getestet. Heben des Korpers eines Modells lasst es aggressiver erscheinen, Senken weniger aggressiv.
Initial characterization of sheep T-cell growth factor and its species-restricted activity on human, rat, and mouse cells.

Abstract Sheep T-cell growth factor (TCGF) was prepared from concanavalin A-activated sheep peripheral blood cells and subsequently characterized by ammonium sulfate precipitation, gel exclusion chromatography, and isoelectric focussing. The TCGF was found in the 60–80% ammonium sulfate fraction and was shown to have an apparent molecular weight of 32,500 and an isoelectric point in the range pI 5.2–5.5. The ability of the sheep TCGF to promote proliferation of activated human, sheep, mouse, and rat cells was compared with that of human TCGF prepared by phytohemagglutinin stimulation of lymphocytes from multiple donors and TCGF prepared from concanavalin A-stimulated rat and mouse spleen cells. Human TCGF was found to act across all species barriers, rat TCGF supported the growth of cells of all species except human, and mouse only promoted the growth of activated mouse and rat cells. Sheep TCGF was unique in being unable to support the growth of any cells except autologous Cells.
Genetics and mapping of the R 11 gene conferring resistance to recently emerged rust races, tightly linked to male fertility restoration, in sunflower ( Helianthus annuus L.)

Sunflower oil is one of the major sources of edible oil. As the second largest hybrid crop in the world, hybrid sunflowers are developed by using the PET1 cytoplasmic male sterility system that contributes to a 20 % yield advantage over the open-pollinated varieties. However, sunflower production in North America has recently been threatened by the evolution of new virulent pathotypes of sunflower rust caused by the fungus Puccinia helianthi Schwein. Rf ANN-1742, an 'HA 89' backcross restorer line derived from wild annual sunflower (Helianthus annuus L.), was identified as resistant to the newly emerged rust races. The aim of this study was to elucidate the inheritance of rust resistance and male fertility restoration and identify the chromosome location of the underlying genes in Rf ANN-1742. Chi-squared analysis of the segregation of rust response and male fertility in F(2) and F(3) populations revealed that both traits are controlled by single dominant genes, and that the rust resistance gene is closely linked to the restorer gene in the coupling phase. The two genes were designated as R ( 11 ) and Rf5, respectively. A set of 723 mapped SSR markers of sunflower was used to screen the polymorphism between HA 89 and the resistant plant. Bulked segregant analysis subsequently located R ( 11 ) on linkage group (LG) 13 of sunflower. Based on the SSR analyses of 192 F(2) individuals, R ( 11 ) and Rf5 both mapped to the lower end of LG13 at a genetic distance of 1.6 cM, and shared a common marker, ORS728, which was mapped 1.3 cM proximal to Rf5 and 0.3 cM distal to R ( 11 ) (Rf5/ORS728/R ( 11 )). Two additional SSRs were linked to Rf5 and R ( 11 ): ORS995 was 4.5 cM distal to Rf5 and ORS45 was 1.0 cM proximal to R ( 11 ). The advantage of such an introduced alien segment harboring two genes is its large phenotypic effect and simple inheritance, thereby facilitating their rapid deployment in sunflower breeding programs. Suppressed recombination was observed in LGs 2, 9, and 11 as it was evident that no recombination occurred in the introgressed regions of LGs 2, 9, and 11 detected by 5, 9, and 22 SSR markers, respectively. R ( 11 ) is genetically independent from the rust R-genes R ( 1 ), R ( 2 ), and R ( 5 ), but may be closely linked to the rust R-gene R ( adv ) derived from wild Helianthus argophyllus, forming a large rust R-gene cluster of R ( adv )/R ( 11 )/R ( 4 ) in the lower end of LG13. The relationship of Rf5 with Rf1 is discussed based on the marker association analysis.
Diurnal and seasonal variations in industrial fatigue of shift workers

The interview was carried out with 1664 steelworkers in the aim of obtaining their opinion on subjective fatigue accompanying the work on morning, afternoon and night shifts. Warm and cold seasons of the year were treated separately. Continuous work observations and telemetric heart rate registration were conducted at some workplaces. Analysis of results exhibited a great differentiation of fatigue estimation on particular shifts. Influence of the seasonal factor was found to be very important both in the reported feeling of fatigue as in changes of the pulse rate. Conclusions concern the ergonomic approach to fatigue problems in shift work. Language: en
Holomorphy rings and higher level orders on skew fields

The intimate connections which exist between higher level orders, sums of 2n th powers, valuation theory, and real-valued places on a field have been explored extensively. Craven initiated the study of similar notions for skew fields in [4]. In [12] we pursued these ideas, but the best results required a 2-primary assumption. This paper extends the work of [12]; in particular, we prove an “Artin-Schreier” theorem for preordered skew fields, namely that a preorder T in a skew field is the intersection of the kernels of all the signatures that contain T. This allows us to obtain the results of [12] without the 2-primary assumption. In particular, we have that preordered skew fields give rise to spaces of signatures, Mulcahy’s abstract setting for the theory of higher level forms and reduced Witt rings. Our main tools are valuation theory and the Kadison-Dubois representation theorem for partially ordered rings. As in the field case, we make use of the ring A, associated to a preorder T, which is the intersection of certain valuation rings. Along the way to our main theorem we prove some facts about noncommutative Priifer rings, and we show that A, is a Priifer ring. While our study of preordered skew fields follows along lines which are familiar from the field context, there are significant differences between the two theories. For example, there are skew fields which have no orders, but admit valuation rings with ordered residue fields.
Response to Letter Regarding Article, “Habitual Coffee Consumption and Risk of Heart Failure: A Dose-Response Meta-Analysis”

We thank Dr Palatini for his discussion of how the relationship between coffee consumption and heart failure may be impacted by the CYP1A2 gene. As we noted1, previous studies have shown that the CYP1A2 gene modifies the association between coffee consumption and myocardial infarction. We agree that …
Numerical Simulation and Experimental Study of Gas Flow Dynamics in Porous Media: Application in Cold Box Foundry Process

The results of an experimental study and 3D numerical simulations of resin bonded sand/air flow in a square corebox with an H-shape insertion and passage between upper and lower pockets of the pattern are presented. A computer controlled electronic system was designed and built to measure pressures and flow rates inside the corebox during mold filling, gassing and purging cycles of Phenolic Urethane Amine (PUA) process. Contour maps of the pressure distributions inside the corebox were created based on barometric measurements. A good agreement between experimental results and numerical simulations was found.Copyright © 2003 by ASME
Treatment of Streptozotocin-Induced Diabetic Rats With AVE7688, a Vasopeptidase Inhibitor: Effect on Vascular and Neural Disease

In epineurial arterioles, acetylcholine-mediated vascular relaxation is mediated by nitric oxide and endothelium-derived hyperpolarizing factor (EDHF), and both mechanisms are impaired by diabetes. The mediator responsible for the effect of EDHF is unknown. In epineurial arterioles, C-type natriuretic peptide (CNP) has properties consistent with EDHF-like activity. Epineurial arterioles express CNP, and exogenous CNP causes a concentration-dependent vascular relaxation. In streptozotocin-induced diabetic rats, CNP-mediated vascular relaxation in epineurial arterioles is decreased. Since CNP may be a regulator of vascular function, a vasopeptidase inhibitor may be an effective treatment for diabetes-induced vascular and neural disease. Vasopeptidase inhibitors inhibit ACE activity and neutral endopeptidase, which degrades natriuretic peptides. Streptozotocin-induced diabetic rats were treated with AVE7688 (450 mg/kg in the diet), a vasopeptidase inhibitor, for 8-10 weeks after 4 weeks of untreated diabetes. Treatment of diabetic rats corrected the diabetes-induced decrease in endoneurial blood flow, significantly improved motor and sensory nerve conduction velocity, prevented the development of hypoalgesia in the hind paw, and reduced superoxide and nitrotyrosine levels in epineurial arterioles. The diabetes-induced decrease in acetylcholine-mediated vascular relaxation by epineurial arterioles was significantly improved with treatment. These studies suggest that vasopeptidase inhibitors may be an effective approach for the treatment of diabetic vascular and neural dysfunction.
What are the greatest challenges and/or barriers to applying postmortem imaging in paediatric radiology?

Without accurate final diagnoses we are unable to audit our work and society cannot properly manage its health care systems. Modern imaging is not yet 100% accurate and in some situations there may be insufficient time to fully investigate. Yet, non-forensic autopsies have become virtually extinct. Postmortem imaging, MRI in particular, with or without minimally invasive autopsy, provides a solution that is more socially acceptable. However, there are a great number of obstacles outside of the well-equipped, well-staffed forensic institute, i.e. where most of us work in the real world. First, access to the scanner for the corpse, both within days of death and at a suitable time of day that does not cause distress to waiting patients. This is difficult when waiting lists for the living are long and scanners already run extended hours. Second, appropriate training of what will initially be a small group of subspecialists. Postmortem imaging is not just the simple transfer of clinical knowledge to postmortem diagnosis. Third, the development of multidisciplinary teams. Failure to do so will result in failure of the entire objective and may risk the specialty becoming part of pathology, not radiology. How many radiologists undertake echocardiography? Finally, money. Hospitals struggling with their budgets will have to be convinced of the benefits when asked to fund such things as increased staff costs, training costs and data storage.
Support for symmetric shadow memory in multiprocessors

Runtime monitoring support serves as a foundation for the important tasks of providing security [15, 14, 2], performing debugging [13, 11, 8], and improving performance of applications [1]. Runtime monitoring, typically, requires the maintenance of meta data associated with each of the application's original memory location, which are held in corresponding shadow memory locations. Each original memory instruction (OMI) is then accompanied by additional shadow memory instructions (SMIs) that manipulate the meta data associated with the memory location. Often the SMIs associated with OMIs are symmetric, in that, original stores (loads) are accompanied by shadow stores (loads). Unfortunately, existing shadow memory implementations need thread serialization to ensure that OMIs and SMIs are executed atomically [12]. Naturally this is not an efficient approach, especially in the now ubiquitous multiprocessors.In this paper, we present an efficient shadow memory implementation that handles symmetric shadow instructions. By coupling the coherency of shadow memory with the coherency of the main memory, we ensure that the SMIs execute atomically with their corresponding OMIs. We also couple the allocation of application memory pages with its associated shadow pages, for enabling fast translation of original addresses into corresponding shadow memory addresses. Our experiments show that the overheads of run-time monitoring tasks are significantly reduced in comparison to previous software implementations.
The case of the disappearing firms: empirical evidence and implications

Organizational survival represents a vital objective for firms, managers, and owners. Most organizational theories regard survival as the ‘correct’ outcome for firms whose managers successfully navigate across a hostile competitive landscape. On the other hand, when a firm ‘disappears,’ scholars, managers, and owners ask, What went wrong?' Failure, exit, bankruptcy, liquidation, hostile takeovers, are largely viewed as results of managerial ‘bungling.’ Many theories about performance, competitive advantage, legitimacy, and leadership rest upon a core assumption that firms, at least some of them, have long, perhaps limitless, life-spans. Long-term survival is not seen as merely a random outcome or an unattainable goal. This paper surveys a broad set of empirical findings about firms' life-spans. It is consistently revealed in the empirical literature that the VAST majority of firms, even large firms, survive relatively short periods. Some themes and their implications are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
DOPE facilitates quaternized lipidoids (QLDs) for in vitro DNA delivery

Abstract This paper describes the synthesis of a combinatorial library of quaternized lipidoids (QLDs) and an evaluation of their abilities to facilitate in vitro DNA delivery. The QLDs alone showed low efficiency for DNA delivery. By formulating liposomes with a neutral helper lipid, such as 1,2-dioleoyl- sn -glycero-3-phosphoethanolamine (DOPE), the capability of QLDs for gene transfection is significantly enhanced due to the fusogenic properties of DOPE which facilitate endosomal escape and cargo delivery. We further optimized the liposome composition and DNA dose for gene transfection and investigated the structure–activity relationships of the lipidoid library in DNA delivery. From the Clinical Editor This paper describes the synthesis and evaluation of a combinatorial library of quaternized lipidoids to facilitate in vitro DNA delivery, which occurs at a low level but can be enhanced with DOPE. The authors also further optimized the liposome composition and DNA dose for delivery and investigated the structure-activity relationships of the lipidoid library.
There Is No Such Cell as a Human Embryonic Stem Cell– At Least, Not Yet

Abstract Separate and apart from the scientific truths of the tenets of human embryology taught to all medical students by lecture and text, political parsing of these tenets has been rampant for many years. It is time to reclaim these scientific truths before it becomes too late. The American Association of Anatomists should allow for a fair and balanced dialogue on human embryonic stem-cell research. It further should accept the fact that a true human embryonic stem cell has not been identified—at least, not yet.
Relaxation and Diffusion Enhanced Dispersive Waves

The development of shocks in nonlinear hyperbolic conservation laws may be regularized through either diffusion or relaxation. However, we have observed surprisingly that for some physical problems, when both of the smoothing factors - diffusion and relaxation - coexist, under appropriate asymptotic assumptions, the dispersive waves are enhanced. This phenomenon is studied asymptotically in the sense of the Chapman-Enskog expansion and demonstrated numerically.
Natural History and Determinants of Conduction Defects Following Coronary Artery Bypass Surgery

Abstract Ninety-three consecutive patients undergoing coronary artery bypass grafting (CABG) were followed prospectively to ascertain the natural history and determinants of new postoperative conduction defects. Each patient was followed in the postoperative period with serial electrocardiograms and continuous monitoring. In the last 70 patients, a technetium pyrophosphate scan was obtained 48 to 72 hours after operation. Postoperatively, new bundle-branch or fascicular block developed in 42 patients (45%) and third-degree atrioventricular (AV) block, in 4 (4%). The occurrence was compared with patient age, preoperative bundle-branch block or fascicular block, number of diseased arteries, number of bypassed arteries, total time of cardiopulmonary bypass, aortic cross-clamping time, occurrence of a preoperative or perioperative myocardial infarction, and presence of disease in the left anterior descending or right coronary artery. Only the number of bypassed arteries, the total time of cardiopulmonary bypass, and the aortic cross-clamping time were related to the development of postoperative conduction defects (all, p In conclusion, following CABG, (1) the occurrence of new AV conduction defects is related to the number of vessels bypassed, the cardiopulmonary bypass pump time, and the aortic cross-clamping time; (2) new conduction defects occur frequently, but the resolution rate is high and third-degree AV block is rare if it is not present by postoperative day 1; (3) because resolution of third-degree AV block may be only transient, patients who have recovered from AV block should be observed for several days before discharge; and (4) ventricular demand pacing may be adequate in patients who require a pacemaker at the time of discharge, because the AV block may resolve by two months of follow-up.
A culture model for age-related human neurofibrillary pathology

Cloned human neuroblastoma cells have been induced to differentiate with retinoic acid whereupon they form an extensive network of processes and pseudoganglia. Ultrastructural examination shows these processes often contain assembled neurofilaments arranged parallel to microtubules in orderly arrangements characteristic of normal neurons. Perturbation of these differentiated, ganglion like cells with agents such as aluminum, zinc, and possibly leupeptin results in apparent neurofibrillary pathologies as evidenced by neurofilament specific immunofluorescent microscopy. A quantitative increase in neurofilament-specific antibody binding induced by aluminum and leupeptin were verified by flow cytometry with a fluorescence activated cell sorter. The utility of this system in screening agents for their capacity to produce neurofibrillary lesions characteristic of age-related human disorders is discussed.
MORPHOLOGIC AND IMMUNOPHENOTYPIC CHARACTERIZATION OF A CELL LINE DERIVED FROM LIVER TISSUE WITH EPSTEIN-BARR VIRUS ASSOCIATED POST-TRANSPLANT LYMPHOPROLIFERATIVE DISEASE

A B-cell line was established from the liver of an 11-yr-old boy with Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disease (PTLD). The cells were morphologically heterogenous, CD10 (CALLA) negative, and expressed several B-cell antigens, including CD23, in a manner reminiscent of lymphoblastoid cell lines (LCLs) reported in the literature. However, the cells also showed expression of the CD77 antigen, carried a 14q32+ chromosomal anomaly, and showed IgM-kappa immunoglobulin isotype restriction immediately after their outgrowth in culture. These latter properties are typically associated with Burkitt’s lymphoma cell lines rather than LCLs. Aberrant expression of the L60 antigen on these B-cells was found as additional evidence of altered growth regulation in these cells. EBV infection was demonstrated by the abundant expression of EBNA-2 and LMP viral antigens in culture. The cell line described should be useful in planning in vitro experiments designed to understand the factors that modulate the growth of PTLD in vivo.
Acid denaturation of the B875 light-harvesting complex in membranes of Rhodobacter sphaeroides.

The structural basis for the spectral red shift in the near-IR absorption band of the B875 light-harvesting complex was examined by treatment of membranes from Rhodobacter sphaeroides M21 with acid. This mutant strain lacks the overlapping spectral bands of the B800–850 light-harvesting antenna and gives rise to membrane fragments with both surfaces accessible to protons. At pH 2.2, about half the absorption at 876 nm was converted within 10 min to a ‘free’ pigment band; the remaining absorption appeared at 880 nm and shifted to ∼845 nm over the next three hours. These spectral shifts could not be reversed by alkali. Approximately one-third of the characteristic near-IR CD signal of B875 was also lost initially and replaced by a broad trough centered near 854 nm. Thereafter, the CD spectrum was dominated by the strong conservative signal of the 845 nm absorbing component which was attributed to an oligomeric bacteriopheophytin a species, probably a dimer. A kinetic analysis of the acid-induced absorption changes suggested a multi-step model with rate constants of 0.37 min-1 for the initial rapid change and 0.05 and 0.11 min-1 for the respective subsequent steps. The non-conservative nature of the near-IR CD spectrum of the intact complex, together with the spectral changes observed after the initial loss of near-IR absorption and CD, suggest that pigment-pigment interactions are not solely responsible for the red shift in this complex.
EFFECTIVE APPLICATION OF NASAL STEROID SPRAY IN COMMON PRACTICE

Nasal steroid sprays have become a mainstay in the medical treatment of chronic allergic and nonallergic rhinosinusitis. Their effect is dependent on the topical application of the steroid to the nasal mucous membrane. When used properly, the spray should be aimed toward the lateral nasal wall. Specifically, 2 anatomic sites linked to the symptomatology of chronic rhinosinusitis, the inferior turbinate and the middle meatus, are targeted. We conducted a prospective study in patients who regularly use a topical nasal steroid spray to determine the actual distribution of the medication on the nasal mucosa. Participants in the study were given a sample bottle of an aqueous steroid nasal spray that had been colored with a nontoxic food dye, and were instructed to use the spray in their usual manner. Bilateral anterior rhinoscopy and fiberoptic nasal endoscopy were performed after application of the spray to determine its location on the nasal mucosa. The intranasal examination was repeated after 15 minutes to allow for redistribution of the medication by mucociliary transport. Findings were recorded after each examination and are discussed along with potential clinical implications.
New guidelines for deposition of nucleic acid structures

Joel L Sussman and Helen M Berman: From January 1, 1996, data for crystal structures of oligonucleotides should be deposited directly with the Nucleic Acid Database (NDB). Once the data are processed they will be forwarded to the Protein Data Bank (PDB) for deposit in the central single archive. This will simplify current procedures and make the data on nucleic acids available more quickly. Protein–nucleic acid complexes and all NMR structures should continue to be deposited at the PDB. All crystal structure data for DNA and RNA will continue to be available from both the NDB and the PDB.To deposit the data, submit the coordinates, structure factors and current PDB deposition form to:deposit@ndbserver.rutgers.edu.A preprint of the related manuscript should be mailed or faxed to:Anke Gelbin, The Nucleic Acid Database, Department of Chemistry, Rutgers, The State University of New Jersey, PO Box 939, Piscataway, NJ 08855-0939, USA.Fax: (908) 445 5958.
Drug testing and social control: Implications for state theory

A new War on Drugs became the rallying cry during the 1986 Congressional elections. One of the major components of this war was the call for mandatory drug testing of workers. We argue that drug testing has more to do with power than with genuine efforts at reducing the consumption of illicit drugs and then proceed to analyze this expansion of power by capitalists and state managers. Contrary to Block's version of state theory, the power of capitalists and state managers expanded simultaneously. We thus conclude by calling for a partial modification of his model.
Managing Change : Today's Challenge to Management

This article presents a review of the book “Managing Change: Today's Challenge to Management,” by John E. Flaherty.
Structural composition and optical properties of solar blacks: gold black

Specimens of gold black (a test solar black system) were produced under controlled laboratory conditions so as to study the dependence of their optical properties on the particlelike nature of the material. A theoretical model incorporating the particulate nature of the gold black films has been applied to describe their optical properties. The electron collision frequency calculated within the framework of the model is significantly larger than that predicted from the particle size effects, and the interband contribution to the absorption coefficient is noticeably smaller for the small (40–85 A) gold particles than for bulk gold. The dependence of the absorption coefficient on particle size has also been determined.
Effect of lubricant chemistry on the performance of end pivoted roller follower valve train

Abstract Real production engine employing end pivoted roller follower valve train has been instrumented to investigate the effects of engine operating conditions, lubricant rheology and chemistry on the sliding of rollers. The experimental results showed that due to shear drag it was not necessary for roller rotational speed to increase with camshaft speed. The lubricant viscosity played a key role in the roller slip at lower temperatures however at higher oil temperatures negative slip was also observed indicating that component inertia and internal friction have a role to play in roller slip. The results also clearly showed the impact of viscosity improvers on roller slip. The experimental setup, test procedure and results are presented in this research work.
1 μJ, sub-500 fs chirped pulse amplification in a Tm-doped fiber system

We demonstrate a Tm-doped fiber laser system producing ∼300 fs pulses with 1 μJ energy, corresponding to peak powers greater than 3 MW. Pulses of 150 fs with 30 nm spectral bandwidth and 3 nJ pulse energy are generated in a Raman-soliton self-frequency shift amplifier, then stretched to ∼160 ps using a chirped Bragg grating. The 60 MHz oscillator repetition rate is reduced to 100 kHz using an electro-optic modulator. After a single-mode fiber preamplifier and a large-mode-area fiber power amplifier, pulses were compressed using a folded Treacy grating setup to below 500 fs with up to 1 μJ pulse energy. To the best of our knowledge, this is the highest energy yet demonstrated as well as the first demonstration of peak powers exceeding 1 MW from a Tm:fiber laser system.
Merchandise Fads of Yesteryear—An Informal Look

A survey of 720 students as to their recall of some product fads of past years (1772 to 1975) implies that people possess a relatively fair recollection about such things. Of those remembering, however, only a comparatively few had, or still have, ownership. Inclusion of two truthfulness items suggests a reasonable level of honesty on the part of the respondents.
Photon mass at low temperature

The theoretical observation that gauge symmetries are generally restored at sufficiently high temperature has led us to consider here the conjecture that gauge symmetries are broken at sufficiently low temperature. The photon, for example, would then acquire a non-zero mass mγ below some low temperature T0. Above this phase-transition temperature, the photon would be strictly massless. Present observational limits on the photon mass show only that mγ is negligible for T > 2.7 K ∼10−4 eV. Although we have not discovered any plausible mechanism for electromagnetic gauge-symmetry breaking and therefore cannot estimate T0 or mγ, there is a considerable range of experimentally accessible low temperatures for which there are no stringent constraints on mγ. Non-zero gluon or graviton masses at low temperatures could also have observable consequences.
The Press Image of Community Health Nurses

Ahad The informational quality of press nw about community health nurses is a critical factor in gaining the required public support for the scarce resources needed to advance community health nursing practice. Using content analyses, 2,561 artides on community health nursing for the period 1978-1981 were coded for key message themes and compared with articles on other nusing subjects. Results reveal that although the subject of community health nursing comprised the largest share of all clinical nursing articles, they are (1) less visible in newspapers, (2) distributed unevenly per capita among the various states, and (3) written so as to communicate lowquality infomation. Analysis of annual trends shows that community health nursirlg artides, while expanding in absolute numh, constitute a declining proportion of nursing artides overall, and that the quality of information in current press coverage is diminishing. It is recommended that community health nurses embark on a concerted campaign to improve the quality of information carried in newspapers about their clinical specialty.