cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthetic/Biopolymer Nanofibrous Composites as Dynamic Tissue Engineering Scaffolds

Synthetic/biopolymer composite scaffolds can provide improved flexibility when designing optimized stem-cell-laden tissue repair devices for fiber-reinforced tissues. Composites enable a range of mechanical properties, rates of degradation, and other functional attributes of a degradable scaffold to be finely tuned by modifying polymer sources and their processing techniques. Furthermore, marrying synthetic fibers spun from harsh solvents with polymers spun from mild organic or aqueous-based solvents can allow for delivery of active molecular species in these composites. In the pre-processing fabrication steps, polymers can be selected and combined from traditional or newer high-throughput approaches into networks with properties that reflect the individual components or their interactions. These properties may also depend on the spinning solvents used. In post-processing steps, factors such as the ambient environmental conditions or crosslinking solvent treatments can differentially affect the constituent polymers chosen. Several case studies will be discussed in order to highlight the potential advantages of these approaches. For example, many studies have shown that the mechanical properties of composite mats can be designed with superior or more tissue-like properties than individual polymer sources alone. Further, it has been shown that the degradation rates of the temporary scaffold can be more finely tuned in composites by combining rapidly and slowly degrading systems. The drug and growth factor delivery capabilities of these systems will similarly be reviewed. We conclude with an overview of several tissue engineering approaches that have exploited composite design features and discuss new promising avenues for study.
Reasons Undergraduate Students Majored in Geology across Six Universities: The Importance of Gender and Department.

AbstractOnly 40% of geoscience undergraduate degrees are conferred on women. Little research has examined why more men tend to pursue and persist in geology degrees compared to women. We examined the reasons why undergraduate geology students chose to major in geology, with a particular emphasis on women. We collected data from 391 undergraduate students (46.4% women) enrolled in six geology departments at public, four-year institutions across the United States. Students reported six reasons they were attracted to geology: interest, career opportunities, liking the outdoors, liking the department, being encouraged by someone, and other. Interest was the most frequent reason female and male students reported for being attracted to geology. After interest, liking the geology department (including liking classes, faculty, and the department overall) was the next most frequent reason female students reported for selecting a geology major. It was the second to least frequent reason for male students. Both fema...
Polarization Sensitivity of Antenna Arrays

The manifold of an array with identical antennas is generally assumed to be insensitive to the polarization of the impinging signal except for a complex scale factor which only affects the signal amplitude. Signal polarization is therefore considered in the literature in the context of diversely polarized arrays, which are specifically designed to be sensitive to polarization. In this paper, we show that the manifold of antenna arrays is generally sensitive to signal polarization even when the antennas have the same polarizations (e.g., identical antennas). We develop two measures which indicate the degree to which an array is sensitive to polarization. We show that direction-of-arrival estimation using an array manifold model which is independent of polarization may be biased due to model mismatch and suffer loss of resolution as the signal polarization varies. Numerical examples are presented to verify the analysis.
Fuxxy Logic Control System of Three-Axis CNC Milling Machine

The paper analyses using various models of fuzzy implication in 3-axis CNC milling machine with an autonomous cooling system of a cutting tool. The authors discuss the following models: Mamdani (minimum) product, product (Prod), Einstein product and the bounded difference. Simulation has showed that the best result is obtained using the operator of the fuzzy implication Mamdani (minimum). The authors have also carried out a numerical simulation of the fuzzy control system by the methods of the center of gravity and the difference in areas. The paper describes how the 3-axis CNC milling machine with autonomous cooling system of the cutting tool is connected. A fuzzy-logical system of controlling the parameters of the machine and the cooling system are used for intellectualizing the processes.
Solutions of Problems

The proof may be accomplished by induction. Use the following form of the theorem of total probability: $$P\{ A|C\} = \sum\limits_{j = 1}^\infty P \{ B_j |C\} P\{ A|B_j C\} ,$$ where {B j } is a complete system of events and P{C} > 0.
An improved synthesis of the C15–C28 fragment of laulimalide

Abstract The C15–C28 fragment of the paclitaxel-like antimicrotubule agent laulimalide has been synthesized in 12 linear steps from known epoxide 5 , with an overall yield of 16%. The methyldihydropyran ring of the side chain was efficiently prepared using ring-closing olefin metathesis chemistry. The 19,20-diol stereochemistry originates in starting material 7 and the side chain was appended using a Kocienski-modified Julia coupling.
Capacitive Discharge to Ground of a Flat Metal Disk with a Pin Contact

Capacitance (C) and voltage (V) on a flat disk is calculated as a function of separation (d) from a ground plane. At large d, C and V are constants. C increases as 1/d and V goes to 0 at d=0, eliminating ESD. Adding a contact pin significantly increases ESD risk.
iLoad: In-network Load Balancing with Programmable Data Plane

Several cloud service and data center providers have announced plans to transition towards environmental-friendly green computing. From a computer networking perspective, such transition requires novel routing approaches over traditional networking protocols, more specifically, end-host-driven load balancing. For example, an end-host may issue a request to change its load, based on its current CPU load or energy availability. Our solution, iLoad, collects such requests from end-hosts and computes the routes entirely in the data plane, providing more efficient and reliable operation of a network.
Germline gene de-silencing by a transposon insertion is triggered by an altered landscape of local piRNA biogenesis

Abstract Transposable elements (TE) are selfish genetic elements that can cause harmful mutations. In Drosophila, it has been estimated that half of all spontaneous visible marker phenotypes are mutations caused by TE insertions. Because of the harm posed by TEs, eukaryotes have evolved systems of small RNA-based genome defense to limit transposition. However, as in all immune systems, there is a cost of autoimmunity and small RNA-based systems that silence TEs can inadvertently silence genes flanking TE insertions. In a screen for essential meiotic genes in Drosophila melanogaster, a truncated Doc retrotransposon within a neighboring gene was found to trigger the germline silencing of ald, the Drosophila Mps1 homolog, a gene essential for meiosis. A subsequent screen for modifiers of this silencing identified a new insertion of a Hobo DNA transposon in the same neighboring gene. Here we describe how the original Doc insertion triggers flanking piRNA biogenesis and local gene silencing and how the additional Hobo insertion leads to de-silencing by reducing flanking piRNA biogenesis triggered by the original Doc insertion. These results support a model of TE-mediated silencing by piRNA biogenesis in cis that depends on local determinants of transcription. This may explain complex patterns of off-target gene silencing triggered by TEs within populations and in the laboratory. It also provides a mechanism of sign epistasis among TE insertions. Author Summary Transposable elements (TEs) are selfish DNA elements that can move through genomes and cause mutation. In some species, the vast majority of DNA is composed of this form of selfish DNA. Because TEs can be harmful, systems of genome immunity based on small RNA have evolved to limit the movement of TEs. However, like all systems of immunity, it can be challenging for the host to distinguish self from non-self. Thus, TE insertions occasionally cause the small RNA silencing machinery to turn off the expression of critical genes. The rules by which this inadvertent form of autoimmunity causes gene silencing are not well understood. In this article, we describe a phenomenon whereby a TE insertion, rather than silencing a nearby gene, rescues the silencing of a gene caused by another TE insertion. This reveals a mode of TE interaction via small RNA silencing that may be important for understanding how TEs exert their effects on gene expression in populations and across species.
Streptococcus agalactiae MprF synthesizes a novel cationic glycolipid and contributes to brain entry and meningitis

Group B Streptococcus (GBS) is a major human pathogen, causing meningitis and severe infection in newborns, yet little is known about its lipid membrane. Here, we investigated the GBS lipid membrane and identify a novel cationic glycolipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG). Multiple peptide resistance factor (MprF) is highly conserved in many bacterial pathogens and plays a critical role in resistance against cationic antimicrobial peptides, cationic bacteriocins, and antibiotics. The MprF protein has been shown to catalyze the amino-acylation of the anionic phospholipid phosphatidylglycerol (PG). Most notably, MprF uses L-lysyl-tRNA to esterify PG with a positively charged lysine to produce lysyl-phosphatidylglycerol (Lys-PG). We demonstrate through heterologous host expression and gene deletion that the GBS MprF has an expanded substrate repertoire and is the biosynthetic enzyme responsible for both Lys-Glc-DAG and Lys-PG biosynthesis in GBS. Furthermore, we demonstrate that MprF contributes specifically to meningitis pathogenesis at the blood-brain barrier both in vitro and in an in vivo hematogenous murine infection model but does not contribute to bloodstream survival. These results greatly expand our knowledge of MprF functions and reveal insights into the survival mechanisms and pathogenesis of meningitis caused by GBS.
Executive function capacity links future thinking and exercise intent.

OBJECTIVE Environmental barriers limit exercise in adolescents, but the contribution of cognitive barriers are not as well characterized. Previous findings suggest future thinking may predict exercise intent, which has been linked to health and actual exercise. However, these models may be incomplete as they do not systematically incorporate potential cognitive contributions (e.g., executive function capacity) to exercise intent. This study investigated the possible mediating role of executive function capacity in the relation between future thinking and exercise intent. METHODS Data for the mediation models was collected from 101 adolescents aged 11-17 (M = 13.09) in a summer enrichment program. Adolescent participants completed self-report measures including Consideration of Future Consequences Scale (CFCS), Intent to Exercise, and Behavior Rating Inventory of Executive Function, Second Edition (BRIEF-2). RESULTS This study found that self-reported executive function capacity mediated the relation between future thinking and exercise intent even when controlling for age and subjective socioeconomic status. CONCLUSIONS While some exercise interventions aim to increase future thinking, this study provides support for additional research into how interventions may benefit from targeting executive function capacity directly to increase exercise intent and actual exercise.
On the Legitimacy of Language-Based Accounting Standards

Reporting schemes have been criticized as being socially constructed, based on norms, and lacking an objective basis to legitimize them. While respecting the norm-like nature of accounting standards, I develop a language-based model in order to gain insight into the roles of the standard setter and supporting infrastructure in promoting legitimacy. I model two threats to legitimacy: managerial rent seeking and a lack of objectivity (disagreement on the meaning of phrases). The results indicate that while increasing penalties (infrastructure) reduces rent seeking and improves objectivity, the standard setter can also reduce rent seeking, but with no effect on objectivity; the arbiter’s conservatism (also infrastructure) reduces rent seeking but lessens objectivity as well; more generic terms increase rent seeking but improve objectivity; and closing loopholes reduces rent seeking but with no affect on objectivity. Moreover, the language-based model affirms the traditional role that conservatism plays in establishing legitimacy.
Some electrical properties of the surfaces of murine B- and T-lymphocytes and thymocytes: II. Effects of neuraminidase and ribonuclease

Abstract The electrical properties of the peripheries of murine thymocytes, B-lymphocytes and T-lymphocytes were studied by measurement of electrophoretic mobilities and electron microscopic quantitation of adsorbed, positively charged CIH particles. The effects of neuraminidase and/or ribonuclease treatment upon these parameters were examined. Neuraminidase-susceptible groups accounted for 17%, 13% and 21% of the net surface negativity of T-lymphocytes, B-lymphocytes and thymocytes, respectively, and 28%, 63% and 78% respectively of particle binding. The calculated numbers of charges at the cellular electrokinetic surface per observed CIH particle were similar in control T-cells and thymocytes and higher than in B-lymphocytes. In neuraminidase-treated T- and B-lymphocytes the calculated charges per CIH particle were much lower than in thymocytes. These results may well indicate heterogeneities in the distribution of groups susceptible to neuraminidase, and also in the distribution and/or chemical nature of anionic groups susceptible to neither neuraminidase nor ribonuclease at the peripheries of different murine lymphocyte populations; however, at present we cannot discriminate between these and other possibilities.
New algorithms for linear k -matroid intersection and matroid k -parity problems

We present algorithms for the k-Matroid Intersection Problem and for the Matroid k-Pafity Problem when the matroids are represented over the field of rational numbers and k > 2. The computational complexity of the algorithms is linear in the cardinality and singly exponential in the rank of the matroids. As an application, we describe new polynomially solvable cases of the k-Dimensional Assignment Problem and of the k-Dimensional Matching Problem. The algorithms use some new identities in mululinear algebra including the generalized Binet-Cauchy formula and its analogue for the Pfaffian. These techniques extend known methods developed earlier for k=2.
Vitamin K epoxide and quinone reductase activities: Evidence for reduction by a common enzyme

Vitamin K hydroquinone formation in rat liver can be catalyzed by a thiol-dependent quinone reductase activity which shares several characteristics with the vitamin K 2,3-epoxide reductase activity. The possibility that a single enzyme catalyzes both reductions was investigated. Values of Vmax/Km for several different vitamin K analogs were determined and found to be similar for both reductase activities. Several different coumarins were also shown to achieve 50% inhibition at similar concentrations for both enzyme activities. The chloro analog of menaquinone-2 was shown to inhibit both reductases, and the presence of either the quinone or epoxide form of the vitamin protected both activities from inactivation. Thioredoxin was shown to function as a reductant for both reductase activities, although the maximum enzyme activity achieved by this reductant was only half that achieved with dithiothreitol as a reductant. Cofractionation of the two reductase activities on a variety of column matrices was also observed. These data strongly support the hypothesis that one microsomal enzyme is capable of catalyzing both reduction of vitamin K 2,3-epoxide to the quinone, and the quinone to vitamin K hydroquinone.
Sink to Source Transition of Populus Leaves

Development of the Populus leaf is presented as a model system to illustrate the sequence of events that occur during the sink to source transition. A Populus leaf is served by three leaf traces, each of which consists of an original procambial trace bundle that differentiates acropetally and continuously from more mature procambium in the stem and a complement of subsidiary bundles that differentiates bidirectionally from a leaf basal meristem. During development these subsidiary bundles maintain continuity through the meristematic region of the node. The basipetally developing subsidiary bunles form phloem bridges that serve to integrate adjacent leaf traces of the stem vasculature. Distal to the node the acropetally developing bundles from all three leaf traces are reoriented in a precise and orderly sequence to form tiers of petiolar bundles. These tiers of bundles extend into the midrib where bundles diverge at intervals as the major lateral veins. The dorsal-most tier of bundles extends to the lamina tip and each successive tier of bundles contributes to lateral veins situated more proximally in the lamina. Although the midrib and the major vein system differentiate acropetally in the lamina, they mature basipetally. Maturation of the mesophyll and other lamina tissues also mature basipetally. As a consequence of the basi-petal maturation process, the lamina tip matures very early and begins exporting photosynthates while the lamina base is still importing from other leaves. The transition of a leaf from sink to source status must therefore be considered as a progression of structural and functional events that occur in synchrony.
Control of a High Performance Aircraft with Unacceptable Zerodynamics

Nonlinear control techniques such as sliding control cannot be directly applied to control the dynamics of many high performance aircraft such as the AFTI-FI6, as they exhibit unacceptable zerodynamics. Traditionally, approximations have been resorted to, to overcome this problem. In this paper, we apply an "output redefinition" technique to systematically overcome the serodynamics problem, resulting in precise, local, tracking. Computer simulations of high g-commands illustrate that while acceptable tracking can be achieved through the output-redefinition technique, standard nonlinear techniques fail.
Resonance tuning and coherent operation in anti-guided vertical-cavity laser arrays

We demonstrate that photonic crystal anti-guided VCSEL arrays can be tuned to coherent operation by control of the cavity resonance by independent control of the bias currents.
Advanced multiplexed readouts for T<15K focal plane arrays

Rockwell International has developed 128 X 128 element multiplexers and very-long- wavelength infrared (VLWIR), Si:As blocked impurity band (BIB) hybrid focal plane arrays (HFPAs) for both low and high flux applications. The multiplexers are fabricated with an n- well CMOS process with 2 micrometers design rules optimized for the <EQ 14 K operating temperature of Si:As BIB detectors. For low flux applications, the unit cell integration capacitance has been reduced to values as small as 0.133 pF and measures to reduce multiplexer photon emission have been implemented. For the high flux regime, the unit cell charge capacity has been maximized with a direct injection input (for large integrated voltage swing) and by using large in-cell capacitance. Devices with a large number of high speed output lines (16) for high frame rate operation have been developed. High quality (near 100% pixel operability with very small (< 3%) nonuniformity) HFPAs have been repeatedly demonstrated with both types of arrays. An improved cryogenic multiplexer process, with 1.2 micrometers design rules, is being used to design and lay out a 256 X 256 element multiplexer for a BIB HFPA. This array, expected in late 1994, will be optimized for high flux applications and will provide improved capability for ground-based, VLWIR imaging instruments for astronomy and other applications.
INHIBITORY CONTROL OF PROXIMAL COLONIC MOTILITY BY THE SYMPATHETIC NERVOUS-SYSTEM:

The purpose of this study is to determine whether or not the sympathetic nervous system provides a tonic inhibitory input to the colon in chloralose-anesthetized cats. Proximal and midcolonic motility were monitored using extraluminal force transducers. An intravenous bolus injection of 5 mg of phentolamine in 14 animals elicited a pronounced increase in proximal colon contractility. The minute motility index changed from 0 +/- 0 to 26 +/- 4 after phentolamine administration. Midcolonic motility also increased in response to phentolamine. Specific blockade of alpha 2-receptors, but not alpha 1-receptors, caused the same response seen with phentolamine. alpha-Adrenergic blockade increased colon contractility after spinal cord transection but not after ganglionic blockade. Blockade of alpha-adrenergic receptors was also performed before vagal and pelvic nerve stimulation and in both cases increased colonic motility. Vagal stimulation alone had no effect on colonic contractility, while pelvic nerve stimulation increased motility at the midcolon. alpha-Receptor blockade did not alter the ineffectiveness of vagal stimulation but did unmask excitatory effects of pelvic nerve stimulation on the proximal colon. All excitatory colonic responses were prevented by blocking muscarinic cholinergic receptors. These data indicate that tonic sympathetic nervous system activity exerts an inhibitory effect on colonic motility. The inhibitory effect is mediated through alpha 2-adrenergic receptors. Based on these findings, we suggest that alterations in sympathetic nervous system activity may be extremely important for the regulation of circular muscle contractions in the colon.
Spectrum scanning when the intruder might have knowledge about the scanner's capabilities

Detecting malicious users in dynamic spectrum access scenarios is a crucial problem that requires an intrusion detection system (IDS) that scans spectrum for malicious activities. In this paper we design a spectrum scanning protocol that incorporates knowledge about the scanning effectiveness across different bands, which can increase scanning efficiency. The adversary, however, can also exploit such knowledge to its advantage. To understand the interplay underlying this problem, we formulate a Bayesian model, where the IDS faces a scanning allocation dilemma: if the intruder has no knowledge, then all the bands are under equal threat, while if the intruder has complete knowledge, then less-protected bands are more likely to be threatened. We solve this dilemma and show the optimal IDS strategy switches between the optimal response to these threats. Finally, we show that the strategy might be sensitive to prior knowledge, which can be corrected by adapted learning.
Association of Aurora-A (STK15) Kinase Polymorphisms With Clinical Outcome of Esophageal Cancer Treated With Preoperative Chemoradiation

BACKGROUND: Aurora-A/STK15 is a serine/threonine kinase critical for regulated chromosome segregation and cytokinesis. We investigated the association between 2 nonsynonymous single nucleotide polymorphisms in the coding region of STK15, T91A (Phe31Ile) and G169A (Val57Ile), and clinical outcome of esophageal cancer treated with preoperative chemoradiation. METHODS: Genotypes at Phe31Ile and Val57Ile were assessed from peripheral blood lymphocytes of 190 esophageal cancer patients and were correlated to response to treatment, recurrence rate, risk of death, disease-free survival (DFS) and median survival time (MTS). RESULTS: All patients had resectable esophageal or gastroesophageal junction cancer and received preoperative chemoradiation followed by esophagectomy. The heterozygous variant Phe31/Ile variant was significantly associated with tumor recurrence (odds ratio [OR] = 4.39; 95% confidence interval [CI], 2.12-8.94; P < .001), shorter DFS (P = .0001), and shorter MTS (P = .012). For patients receiving cisplatin-based therapy, only the variant Phe31/Ile had an adverse effect on response (OR = 2.8; 95% CI, 1.01-5.17; P = .048) and MTS (P = .026). The variant 91A-169G haplotype carried a significant risk for lack of complete response (OR = 2.54; 95% CI, 1.15-5.54) and higher rate of recurrence (OR = 2.73; 95%CI, 1.00-7.29). The presence of at least 1 variant allele at each locus further increased the risk of recurrence (adjusted OR = 6.21; 95% CI, 2.28-17.11; P = <.001), and was associated significantly shorter DFS (P = .003). CONCLUSIONS: Our study shows that functional SNPs in the STK15 gene are associated with higher rate of recurrence, higher likelihood of chemoratiotherapy-resistance, shorter DFS, and shorter MTS. Confirmation of our data and understanding the mechanisms through which STK15 functional SNPs mediate resistance to chemoradiotherapy are warranted. Cancer 2012. © 2011 American Cancer Society.
Architecting processors to allow voltage/reliability tradeoffs

Escalating variations in modern CMOS designs have become a threat to Moore's law. While previous works have proposed techniques for tolerating variations by trading reliability for reduced voltage (energy) [10], the benefits of such techniques are limited, because voltage/reliability tradeoffs in conventional processors often introduce more errors than can be gainfully tolerated [14]. Recent work has proposed circuit and design-level optimizations [14, 15] that manipulate the error rate behavior of a design to increase the potential for energy savings from voltage/reliability tradeoffs. In this paper, we investigate whether architectural optimizations can also manipulate error rate behavior to significantly increase the energy savings from voltage/reliability tradeoffs. To this end, we demonstrate how error rate behavior indeed depends on processor architecture, and that architectural optimizations can be used to manipulate the error rate behavior of a processor. We show that architectural optimizations can significantly enhance voltage/reliability tradeoffs, achieving up to 29% additional energy savings for processors that employ Razor-based error resilience.
CERTIFYING NEW TECHNOLOGIES

We study the role of Standard Setting Organization (SSOs) in the adoption of standards. The way the SSO balances the interests of sponsor and users is key to its ability to certify the technology. Proximity to users builds trust in the endorsement, but may be unattractive to technology sponsors. In a static context, we show that the SSO is an effective certifier if and only if it puts enough weight on users' interests. We then tackle the more challenging problem of SSO certification in a dynamic setting in which new information will accrue in the future and user choices are irreversible. The SSO and the users must then both take a dynamic perspective and contemplate the possibility of a “second chance” that may arise for the standard. A key insight is the possibility of multiple self-fulfilling expectations. It is possible to have an equilibrium with no second chance, a lenient SSO endorsement policy and high stigma from early rejection. It is also possible to have an equilibrium with a second chance, a selective SSO endorsement policy and low stigma from early rejection. Finally, and in both the static and the dynamic setups, we ask whether the SSO is too inclined to turn down or to accept the standard from a social viewpoint. (JEL: D71, D82, L15, O31)
The distribution of glycine, a neurotransmitter suspect in the central nervous system of several vertebrate species

Abstract The glycine concentration in the cerebral hemisphere, diencephalon, midbrain, cerebellum, medulla oblongata, certival enlargement, midthoracic cord, and lumbar enlargement in cat, rat, pigeon, caiman and bullfrog was measured by a specific microchemical assay. The glycine concentration was 3–5 times higher in the medulla oblongata, cervical and lumbar enlargements than in the four brain areas rostral to the medulla. It was low in the mid-thoracic spinal cord and in the cerebellum. An increasing rostrocaudal gradient in glycine concentration was generally noted and was most evident in the cat and rat. The high glycine concentration in the cervical and lumbar spinal cord and the medulla is compatible with a possible transmitter function for glycine in these areas.
Comparison of microwave absorption in single-crystal and ceramic YBaCuO

Abstract The magnetic field dependence of the microwave absorption of superconducting Y 1 Ba 2 Cu 3 O x was measured as a function of temperature. Ceramic samples exhibited hysteresis, remanence, and sensitivity to very low magnetic fields. These features were not observed in a single crystal at comparable fields and temperatures. Instead, microwave absorption in the single crystal was highly anisotropic.
The modification of transcapillary exchange by perfusion of non-particulate media

Abstract The effect of blood-borne particulate matter on the effective flow in skeletal muscle was examined in the skinned hind limb of cats with normal arterial supply, perfused at normal flow-rates with whole blood, or with particulate free iso-oncotic media. Effective circulation was assessed from clearance of radioactive sodium iodide after intra-arterial administration. Clearance during perfusion with oxygenated whole blood did not differ from that observed during self-perfusion with normal arterial supply. Clearance increased during perfusion with plasma or plasma substitutes (173% with oxypolygelatin, 153% with 6% Dextran in saline). Generally, media with the lowest hematocrit produced the greatest increase in clearance rate. Perfusion with N 2 -treated whole blood also enhanced the clearance rate but the increased slope may reflect changes in pCO 2 or pH as well as pO 2 . It was concluded that the rate of movement across vessels perfused with particulate free media was enhanced. The probabilities that (a) “metabolic” vasodilatation and (b) altered flow characteristics contributed to these changes is discussed.
Regulation of the phagocyte respiratory burst by small GTP-binding proteins

Bacteria phagocytosed by leukocytes are killed and degraded by toxic oxygen metabolites produced in the phagosome via an NADPH oxidase. NADPH oxidase activity is regulated by small GTP-binding proteins in response to phagocytic stimuli. In this review, Gary Bokoch focuses on the role of Rac in regulating this important phagocytic process.
DEMAT: sustainability assessment of new flexibility-oriented business models in the machine tools industry

New flexibility-oriented business models represent a novelty in business model research. They aim at optimising the management of manufacturing flexibility in turbulent environments through the offering of added-value services by system suppliers. However, they are currently defined at theoretical level and their economic sustainability for customers and suppliers has to be quantitatively demonstrated. In this paper, a methodology to assess the economic performance of flexibility-oriented business models based on probabilistic event-decision trees modelling is presented. The methodology was applied to a real industrial case and simulations were performed to identify win-win conditions that make business models sustainable for customer and supplier. Results allowed to understand which are the main variables determining flexibility-oriented business models’ success and they constitute a reference for companies willing to innovate their business model in this direction.
Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group.
The politics and economics of pork barrel spending: The case of federal financing of water resources development

This paper empirically investigates the economic and political factors that have influenced annual Corps of Engineers water resource spending. Despite the common view that “pork barrel” spending is economically unjustified and purely politically motivated, economic factors have been important in determining water resource spending. From 1865–1920, economic development and industrialization increase spending, and from 1921–1988, spending appears to be counter-cyclical. There is also evidence that majority parties control spending levels in the post-Civil war period, while in recent times, legislators act under a norm of “constrained universalism” and are influenced by the costs to their constituents of increased spending.
Kinetic characterization of a novel cationic (99m)Tc(I)-tricarbonyl complex, (99m)Tc-15C5-PNP, for myocardial perfusion imaging.

Background Intense liver uptake of 99mTc-sestamibi (MIBI) often interferes with visualization of myocardial perfusion in the inferior wall of the left ventricle. To develop improved myocardial perfusion agents, crown ether-containing dithiocarbamates and bisphosphines have been introduced in recent years. This study was designed to investigate the myocardial imaging properties and in vivo kinetics of a cationic 99mTc(I)-tricarbonyl complex, 99mTc-15C5-PNP, in comparison with MIBI.
A comparison of two nitrification inhibitors used to measure nitrification rates in estuarine sediments

Abstract Nitrification rates were measured using intact sediment cores from South San Francisco Bay and two different nitrification inhibitors: acetylene and methyl fluoride. Sediment oxygen consumption and ammonium and nitrate fluxes were also measured in these cores. Four experiments were conducted in the spring, and one in the fall of 1993. There was no significant difference in nitrification rates measured using the two inhibitors, which suggests that methyl fluoride can be used as an effective inhibitor of nitrification. Nitrification was positively correlated with sediment oxygen consumption and numbers of macrofauna. This suggests that bioturbation by macrofauna is an important control of nitrification rates. Irrigation by the tube-dwelling polychaete, Asychis elongata , which dominates the benthic biomass at this location, appears particularly important. Ammonium fluxes out of the sediment were greatest about one week after the spring bloom, while nitrification peaked about one month later.
Steady-state regulation of the human DNA mismatch repair system.

Steady-state levels of human DNA mismatch repair (MMR) transcripts and proteins were measured in MMR-proficient and -deficient cell lines by the newly developed competitive quantitative reverse transcription- polymerase chain reaction and Western analysis normalized with purified proteins. In MMR-proficient cells, hMSH2 is the most abundant MMR protein and is expressed 3 to 5 times more than hMLH1. The hMLH1 protein was expressed 1.5 to 2.5 times more than hPMS2. Steady-state levels of mRNA expression correlated well with protein expression. hMSH2-mutated LoVo cells did not express detectable hMSH3 or hMSH6 proteins. Similarly,hMLH1-mutated HCT116 cells did not express detectable hMLH1 or hPMS2 protein, whereas in hMLH1-restored HCT116+ch3 cells, hPMS2 protein was re-expressed. In hMSH6-mutated HCT15 cells, both hMSH3 protein and mRNA were increased. In SV40-transformed lung fibroblasts, all MMR mRNAs and proteins examined were expressed at levels 1.5–5-fold higher than in their nontransformed counterpart. The steady-state levels of MMR proteins indicate that substantially more hMutS proteins, which are involved in DNA mismatch recognition, are present in comparison with the hMutL proteins. Stability of hMSH3 and hMSH6 proteins appears to depend upon the presence of the hMSH2 protein, and, similarly, the stability of the hPMS2 protein depends upon hMLH1. When the hMSH6 is mutationally inactivated, hMSH3 increases by both transcriptional up-regulation and enhanced protein stability. A balanced up-regulation of all of the components was seen after viral transformation in a fibroblast model. Quantitative changes of the MMR components are a potential mechanism to modify the DNA MMR capabilities of a cell.
Correlation energy calculated with various dielectric functions

Abstract The correlation energy of a free electron gas is calculated using the Kleinman-Langreth and screened Hubbard dielectric functions and compared with that calculated previously with four other dielectric functions as well as with the Nozieres-Pines results.
The “Discovery” of Child Abuse

This paper represents a study of the organization of social forces which gave rise to the deviant labelling of child beating and which promoted the speedy and universal enactment of criminal legislation in the mid-1960s. Initial consideration is given to an historical survey of social reaction prior to the formulation of a fixed label. Specific attention is focused on the nineteenth-century “house of refuge movement,” early twentieth+century crusades by the Society for the Prevention of Cruelty to Children and the rise of juvenile courts. A second section concentrates on the web of cultural values related to the protection of children at the time of the “discovery” of abuse as deviance. A third section examines factors associated with the organizational structure of the medical profession conducive to the “discovery” of a particular deviant label. The final segment of the paper concerns resultant social reaction. The paper synthesizes conflict and labelling perspectives in providing an interpretation of a particular social-legal development.
A Field-Theory Formulation of the Parton Model

A formulation of field theory given by Van Hove in 1955 is shown to be useful for putting parton-model-like ideas'' on firm theoretical grounds. This is done by discussing electron-proton deep-inelastic scattering, electron- positron annihilation, and the proton elastic form factor. A basic requirement that must be imposed on any field theory in order to discuss the concept of hadronic constituents is given. To put the formulation on a firm ground (with respect to renormalizability), we assume that the wave-function renormalization constants of the theory are finite. This assumption satisfies the above- mentioned basic requirements, though it probably is not necessary. Within this framework we prove that nu W2(q2, nu ) is the same as that derived in the parton model. In this formalism, electron-positron annihilation is quite different in character from deep-inelastic electron-proton scattering. The constancy of the ratio sigma (e+e yields hadrons)/ sigma (e+e → mu + mm) can be derived only if much stronger assumptions than the one mentioned above are adopted.The price paid for simplicity in the renormalization procedure is two physically undesirable results: (a) The proton elastic form factor is probably finite at large momentum transfer. and (b) nu W2 is finite and nonzero atmore » x=1. It is conjectured that these problems can be solved without changing other results by allowing wave-function renormalization constants to become infinite.« less
A scalable distributed shared memory architecture

Abstract Scalability of a multiprocessor architecture depends on its ability to manage interconnection network latency with increasing number of processors. Interconnection network latency can be minimized by reducing the distance traversed by a message in terms of number of nodes and wire lengths. Scalability of a DSM architecture also depends on the scalability of the coherency protocol and the associated directory storage requirements. In this paper we describe a DSM architecture based on a fat tree interconnection network with augmented switching nodes. The proposed architecture is CC-NUMA, but supports several important features of COMA architectures. The scalability of this architecture is enhanced by integrating routing and cache coherency operations, which helps in improving locality by trapping requests locally. Scalability of a DSM architecture is defined and evaluated in terms of the asymptotic speedup of an algorithm with increasing number of processors.
Wavelength selective materials modification of bulk As2S3 and As2Se3 by free electron laser irradiation

Abstract In this study we report first measurements of wavelength-selective infrared-induced materials modification of bulk As2S3 and As2Se3. These materials are currently being considered as candidate materials for infrared optical fiber transmission in the range of 1–10 μm. Our study is aimed at modifying oxygen, hydrogen and carbon impurities bound to chalcogenide constituent elements in the materials to reduce absorption. Tunable infrared radiation from the W.M. Keck Free Electron Laser (FEL) at Vanderbilt was used to excite specific vibrational modes, S–O–H and CHx modes in bulk As2S3 and Se–H, CHx and S–H2 modes in bulk As2Se3. Changes in vibrational mode amplitudes are monitored by measuring the intensity of the Fourier transform infrared (FTIR) spectra before and after irradiation at appropriate wavelengths. By tuning wavelengths to hydrogen vibrational modes, we find evidence that hydrogen is released and/or redistributed athermally. In particular, following irradiation at specific resonant wavelengths, vibrational mode amplitudes as monitored by FTIR associated with CHx are significantly reduced in bulk As2S3 and As2Se3 samples. In As2S3, the changes in CHx modes are reversed by heat treatment at 115°C for 35 min in nitrogen atmosphere.
Tooth Size Reduction: A Hominid Trend

C. L. Brace proposes that the reduction in the size of the anterior teeth in hominid phytogeny resulted from the accumulation of random mutations when these teeth became selectively neutral as a result of increased tool use. In contrast, we contend that the incisors have adaptive significance; they reflect the selection pressures on the whole functional matrix in which they exist. Moreover, the accumulation of mutations is not biologically possible without affecting the fitness of the whole organism. Lastly, there is no apparent relationship between the size of the anterior teeth and the level of technology in contemporary populations, as the Brace model would predict.
The importance of soil sampling depth for accurate account of soil organic carbon sequestration, storage, retention and loss

article i nfo Soil organic carbon sequestration Rooting depth Soil organic carbon stocks Soil sampling depth Soil organic carbon distribution within soil profile is highly influenced by management practices, especially tillage systems where soil environment is altered. Such changes in soil environment will affect soil carbon reten- tion or accumulation in different layers of the soil profile. However, much published research in the area of soil organic carbon (SOC) sequestration focuses on shallow sampling depths within the 0-30 cm tillage zone when determining SOC stocks and sequestration. The objectives of this study are to quantify the SOC stock differences with depth between tillage treatments after 20 years and to determine the appropriate sampling depth when assessing SOC stocks as influenced by management practices. A 20-year moldboard plow (MP), chisel plow (CP) and no-tillage (NT) study was established with a maize-soybean rotation. The 75-cm root zone was sampled in 5-cm intervals to measure SOC stocks. The SOC sequestration, storage, retention and loss were determined for the 0-5 cm, 0-15 cm, 15-75 cm and 0-75 cm layers. The NT treatment did retain more SOC stock than the MP treatment to a 20 cm depth but the SOC stock of the 20-35 cm layer NT system was lower than the MP system. It is recommended that the depth of soil sampling has to include the entire root zone to accurately report SOC stock and the effect of tillage system on change in SOC.
A novel recombinant HLA-B*39 allele (B*3910) in a South African Zulu

The sequence of a new B*39 allele has been identified in a South African Zulu individual. This allele designated B*3910, differs at two nucleotide positions (246 and 272) from B*39011. The difference at position 246 is silent, while that at position 272 results in an amino acid change from cysteine (B*39011) to tyrosine (B*3910). As these same differences are found in other HLA-B alleles, they were probably introduced into the B*3910 sequence by a short gene conversion event with another allele. This finding provides further evidence for the diversification of HLA-B allelic sequences via recombination.
Real-time software methodologies: Are they suitable for developing Manufacturing control software?

Computer-Integrated Manufacturing (CIM) systems may be classified as real-time systems. Hence, the applicability of methodologies that are developed for specifying, designing, implementing, testing, and evolving real-time software is investigated in this article.
Producing scalable performance with OpenMP: experiments with two CFD applications

Abstract OpenMP is a relatively new programming paradigm, which can easily deliver good parallel performance for small numbers (
Mie Scattering Theory for Phonon Transport in Particulate Media

Scattering theory for the scattering of phonons by particulate scatterers is developed in this paper Recently the author introduced the generalized equation of phonon radiative transport (GEPRT) in particulate media, which included a phase function to account for the anisotropic scattering of phonons by particulate scatterer. Solution of the GEPRT showed that scattering cross section is different from the thermal transport cross-section. In this paper formulations for the scattering and transport cross section for horizontally shear (SH) wave phonon or transverse wave phonon without mode conversion is developed. The development of the theory of scattering and the transport cross section is exactly analogous to the Mie scattering theory for photon transport in particulate media. Results show that transport cross section is very different from the scattering cross section. The theory of phonon scattering developed in this paper will be useful for the predictive modeling of thermal conductivity of practical systems, such as nanocomposites, nano-micro-particle-laden systems, etc.
Nuclear Excitation Via The Motion Of Electrons

A method of switching from a nuclear isomeric state to a lasing state is examined. A semi-classical model of laser-electron-nuclear coupling is developed. In it the electrons are treated as free in the external field of the laser, but with initial conditions corresponding to their atomic orbits. Application is made to testing this model in 235U and to the design criteria of a gamma-ray laser.