cssi/SciSciGPT-SciSciNet huggingface dataset:
Surviving Radical Technological Change through Dynamic Capability: Evidence from the Typesetter Industry

Recent work in the field of management has focused on 'dynamic capability', the ability of a firm to develop new capabilities in response to shifts in its external environment, as a significant source of competitive advantage. "This paper enhances our understanding of dynamic technical capability. While most established firms have difficulty adapting when confronted with radical, competence-destroying technological change, Mergentbaler Linotype, a firm founded in 1886, has survived three such revolutions and ltd the market in 1990. An examination of the history of this firm in contrast to other incumbents from the same era highlights two key contributors to dynamic technical capability: external integrative capability and geographically distributed research sites. External integrative capability comprises two elements: internal investments that develop absorptive capacity and an external communication infrastructure to facilitate the transmission of external knowledge. In combination, these elements enable the firm K successfully to identify and integrate knowledge outside its boundaries. Geographically distributed research sites facilitate the development of new technical capability in three j : ways. First, competition among research sites spurs innovation. Second, multiple I locations help to overcome organizational inertia by allowing for the development of ^ different generations of technology in different locations. Finally, multiple locations | provide a source of variation, enabling the firm to leverage differences in local & environments.
Frictional resistance in orthodontic brackets with repeated use.

Abstract This study measured and compared the level of frictional resistance generated with a nonrepeated and repeated experimental design to evaluate whether the wear in the bracket slot will influence frictional resistance. Both 0.018 and 0.022 inch slot size edgewise brackets were tested in a specially designed apparatus. The frictional resistance was measured on an Instron Universal Testing Machine. A repeated measures ANOVA was used to determine differences among the 10 individual bracket wire specimens for each combination to study the influence of wear on static and kinetic frictional force. A paired t test (two-tail) procedure was used to compare the static and kinetic frictional forces in the nonrepeated and repeated study for each bracket slot, wire size, and bracket type. The results show that there was a distinct trend for the mean frictional force to be higher with the repeated use of the brackets. (Am J Orthod Dentofacial Orthop 1999;116:400-404)
Partial regulation of serotonin transporter function by γ-synuclein

Human alpha-synuclein (alpha-Syn) is instrumental in maintaining homeostasis of monoamine neurotransmitters in brain, through its trafficking, and regulation of the cell surface expression and, thereby, activity of dopamine, serotonin and norepinephrine transporters. Here we have investigated whether other members of the synuclein family of proteins, gamma-synuclein (gamma-Syn) and beta-synuclein (beta-Syn) can similarly modulate the serotonin transporter (SERT). In Ltk(-) cells co-transfected with SERT and gamma-Syn, gamma-Syn reduced [(3)H]5-HT uptake, in a manner dependent on its expression levels. The decrease in SERT activity was via decreased V(max) of the transporter, without change in K(m), compared to cells expressing only SERT. By contrast, beta-Syn co-expression failed to alter SERT uptake activity, and neither the V(max) nor the K(m) was changed in the presence of beta-Syn. gamma-Syn modulation of SERT was only partial, with a maximal approximately 27% decrease in SERT activity seen even at high expression levels of gamma-Syn. By contrast, alpha-Syn attenuated SERT activity by approximately 65% at identical expression levels as gamma-Syn. Co-immunoprecipitation studies showed the presence of heteromeric protein:protein complexes between gamma-Syn or alpha-Syn and SERT, while beta-Syn failed to physically interact with SERT. Both alpha-Syn and gamma-Syn colocalized with SERT in rat primary raphae nuclei neurons. These studies document a novel physiological role for gamma-Syn in regulating 5-HT synaptic availability and homeostasis, and may be of relevance in depression and mood disorders, where SERT function is dysregulated.
Motor learning following unilateral stroke

Abstract Objective: To determine the effect of different motor learning schedules on stroke patients' rate of acquisition and retention of a functional movement sequence using the hemiparetic upper limb. Design: Randomized controlled group study using a retention design with two retention trials. Setting: Outpatient neurorehabilitation clinic. Patients: Twenty-four patients with chronic hemiparesis secondary to a single unilateral cerebral stroke without evidence of severe cognitive or language impairment. Main Outcome Measure: The primary hypothesis was that hemiparetic motor learning that occurred under conditions of contextual interference (ie, random practice) would be retained better than learning that occurred under conditions of repetitive drill (blocked practice). Results: A significant difference was found among the three groups (ie, random-practice, blocked-practice, control) on both the first retention measure ( X 2 = 13.50, p X 2 = 12.59, p U = 68.5, p U = 62.0, p = .05). Conclusions: Findings provide empirical evidence to support the contention that random practice is more effective than blocked practice, with respect to retention over time, when hemiparetic stroke patients attempt to learn functional motor skills.
Activation of cellular signaling by 8-oxoguanine DNA glycosylase-1-initiated DNA base excision repair

Accumulation of 8-oxo-7,8-dihydroguanine (8-oxoG) in the DNA results in genetic instability and mutagenesis, and is believed to contribute to carcinogenesis, aging processes and various aging-related diseases. 8-OxoG is removed from the DNA via DNA base excision repair (BER), initiated by 8-oxoguanine DNA glycosylase-1 (OGG1). Our recent studies have shown that OGG1 binds its repair product 8-oxoG base with high affinity at a site independent from its DNA lesion-recognizing catalytic site and the OGG1•8-oxoG complex physically interacts with canonical Ras family members. Furthermore, exogenously added 8-oxoG base enters the cells and activates Ras GTPases; however, a link has not yet been established between cell signaling and DNA BER, which is the endogenous source of the 8-oxoG base. In this study, we utilized KG-1 cells expressing a temperature-sensitive mutant OGG1, siRNA ablation of gene expression, and a variety of molecular biological assays to define a link between OGG1-BER and cellular signaling. The results show that due to activation of OGG1-BER, 8-oxoG base is released from the genome in sufficient quantities for activation of Ras GTPase and resulting in phosphorylation of the downstream Ras targets Raf1, MEK1,2 and ERK1,2. These results demonstrate a previously unrecognized mechanism for cellular responses to OGG1-initiated DNA BER.
Molecular weight distributions from gel-sol ratios

A method for determining molecular weight distributions is presented, based upon the partition of polymer molecules between gel and sol in a partly crosslinked system. It is assumed that the polymer sample consists of a series of molecular weight species, and analysis of previously developed theories covering this situation yields an expression which equates the weight fraction of gel to a summation involving the weight fraction of the material in each species and the number of crosslinked units in the sample. The data are presented in the form of a graph showing how the weight fraction of gel varies as a function of the number of crosslinked units in the sample. Data for the graph are obtained from swelling measurements made in the usual manner. The procedure is outlined for using the information from the graph to make a step-by-step evaluation of the fractional weight of each molecular weight species in the sample for as many fractions as may be arbitrarily chosen. Both a first approximation method and a more refined second approximation method are outlined. The procedure has been applied to samples of natural rubber, synthetic rubbers, and to two known molecular weight distributions.
Effect of phenobarbital and 3-methylcholanthrene treatment on NADPH- and NADH-dependent production of reactive oxygen intermediates by rat liver nuclei.

The effect of inducing the rat liver nuclear mixed-function oxidase system by phenobarbital or 3-methylcholanthrene on NADPH- and NADH-dependent production of reactive oxygen intermediates was evaluated. The inducing agents produced a 2-fold increase in cytochrome P-450, a 50 to 70% increase in NADPH-cytochrome c reductase activity, and a 20 to 30% increase in NADH-cytochrome c reductase activity. Associated with these increases was a corresponding increase in NADPH- and NADH-dependent production of hydroxyl radical (.OH)-like species and of H2O2. Rates of .OH production were inhibited by catalase and partially sensitive to superoxide dismutase. The increase in nuclear production of .OH-like species after drug treatment appears to be due a corresponding increase in H2O2 generation. In contrast to H2O2 and .OH generation, production of thiobarbituric acid-reactive material by nuclei was not increased by the phenobarbital or 3-methylcholanthrene treatment. Redox cycling agents such as menadione and paraquat increased oxygen radical generation to similar extents in the control and the induced nuclei. These results indicate that induction of the nuclear mixed-function oxidase system by phenobarbital or 3-methylcholanthrene can result in a subsequent increase in production of reactive oxygen intermediates in the presence of either NADPH or NADH.
Strategic directions in computational geometry

Computational geometry investigates algorithms for geometric problems. For an introduction to the field, see the textbooks by Edelsbrunner [1987], Mulmuley [1994], O’Rourke [1994], Preparata and Shamos [1985], and the forthcoming handbooks by Goodman and O’Rourke [1997] and Sack and Urrutia [1997]. Resources are also available on the World Wide Web (see, e.g., the Directory of Computational Geometry Software [Amenta 1996], the Computational Geometry Pages [Erickson 1996]), and Geometry in Action [Eppstein 1996]. This article outlines the evolution of computational geometry, discusses strategic research directions with emphasis on methodological issues, and proposes a framework for interaction among computational geometry and related applied fields.
A simple artificial urine for the growth of urinary pathogens

A simple artificial urine medium (AUM) has been developed which provides conditions similar to that found in human urine. AUM solidified with agar enabled the recovery of a wide range of urease-positive and -negative urinary pathogens. Liquid AUM supported growth at concentrations of up to 10(8) cfu ml-1, as found in normal urine. Reproducible, steady-state growth also occurred over many generations in continuous culture. AUM was capable of forming crystals and encrustations resembling those found in natural urinary tract infections. The medium is a suitable replacement for normal urine for use in a wide range of experiments modelling the growth and attachment of urinary pathogens in the clinical environment.
Persistent seasonal variations in the diurnal cycle of earthworms

An annual cycle, based on the differences between the speed of locomotion around midday and in the evening, was found for earthworms,Lumbricus terrestris L., maintained in the laboratory under constant conditions of light and temperature, and studied during parts of 1965, 1966, 1967 and 1968. During each month, the worms were faster in the evening than at noon, but this difference varied in degree through the year (Fig. 1). In addition, during part of the year, the differences between midday and evening were much greater for a 15-day period which centered on full moon than for a block of 15 days centered on new moon. Therefore, seasonal changes in lunar correlations were also indicated. These rhythms have been compared with others of lunar and annual frequencies, and their possible biological significance has been discussed.
Earth-emitted irradiance near the first Lagrangian point

[1] The first Lagrangian point, L-1, is a point between the Earth and the Sun where a mass will be in equilibrium between the gravitational pulls of Earth and Sun and its centrifugal force about the center of mass of the Earth-Sun system. DSCOVER, the first spacecraft planned for Earth observation near L-1, includes a radiometer to measure shortwave and longwave flux from the full disc of the Earth. The latitude of the subsatellite point is near the solar declination, and its longitude is near that for local noon. The spacecraft is always over the tropics. Moreover, it is always over the summer hemisphere. Both of these effects will cause the full-disc measurement of Earth-emitted radiation to be higher than the global mean. In this paper we compute the longwave flux near L-1 using deconvolution theory for wide field-of-view radiometer measurements of Earth-emitted radiation, which makes the computations simple and provides a theoretical framework for understanding the results. The bias due to being over the summer hemisphere will peak twice during the year, so that a semiannual cycle will occur. The global mean Earth-emitted radiation has an annual cycle due to the variation of Earth-Sun distance. If the spacecraft orbit is less than 10° from the Earth-Sun line, the bias to the global mean is computed to be about 8 W m−2 for the annual average with a semiannual cycle of about 1.5 W m−2. In addition to the seasonal cycles, there is a diurnal cycle in the measurement at L-1 as the Earth rotates.
Quantum fluctuation theory

Abstract The incorporation of quantum fluctuations into the calculations of fluctuations in a neutral system is given. The particular application considered is for superfluids. A suggestive gauge invariant formalism is presented and motivated.
Multi-budgeted matchings and matroid intersection via dependent rounding

Motivated by multi-budgeted optimization and other applications, we consider the problem of randomly rounding a fractional solution x in the (non-bipartite graph) matching and matroid intersection polytopes. We show that for any fixed δ > 0, a given point x can be rounded to a random solution R such that E[1R] = (1 − δ)x and any linear function of x satisfies dimension-free Chernoff-Hoeffding concentration bounds (the bounds depend on δ and the expectation μ). We build on and adapt the swap rounding scheme in our recent work [9] to achieve this result. Our main contribution is a non-trivial martingale based analysis framework to prove the desired concentration bounds. In this paper we describe two applications. We give a randomized PTAS for matroid intersection and matchings with any fixed number of budget constraints. We also give a deterministic PTAS for the case of matchings. The concentration bounds also yield related results when the number of budget constraints is not fixed. As a second application we obtain an algorithm to compute in polynomial time an ∈-approximate Pareto-optimal set for the multi-objective variants of these problems, when the number of objectives is a fixed constant. We rely on a result of Papadimitriou and Yannakakis [26].
Clinical findings associated with bladder trabeculations in women

Introduction and hypothesis This study evaluated whether bladder trabeculations are associated with advanced prolapse, urinary urgency, or detrusor overactivity among women undergoing office cystoscopy. It is well established that bladder trabeculations are associated with bladder outlet obstruction (BOO) in men; however, the clinical significance of trabeculations in women is unclear. Whereas an analogous relationship has been proposed between prostatic obstruction in men and advanced pelvic organ prolapse (POP) in women, little data in the medical literature supports this theory.
Light-independent developmental regulation of cab gene expression in Arabidopsis thaliana seedlings.

Abstract We found a transient increase in the amount of mRNA for four nuclear genes encoding chloroplast proteins during early development of Arabidopsis thaliana. This increase began soon after germination as cotyledons emerged from the seed coat; it occurred in total darkness and was not affected by external factors, such as gibberellins or light treatments used to stimulate germination. Three members of the cab gene family and the rbcS-1A gene exhibited this expression pattern. Because timing of the increase coincided with cotyledon emergence and because it occurred independently of external stimuli, we suggest that this increase represents developmental regulation of these genes. Further, 1.34 kilobases of the cab1 promoter was sufficient to confer this expression pattern on a reporter gene in transgenic Arabidopsis seedlings. The ability of the cab genes to respond to phytochrome preceded this developmental increase, showing that these two types of regulation are independent.
Chip parasitic extraction and signal integrity verification (extended abstract)

In was projected by the National TechnologyRoadmap for Semiconductors that by the year 1998 thefeature size will shrink to 0.25μm and the chips maycontain as many as 28 million transistors.As the widthof wires shrinks, resistance increases more rapidly thancapacitance decreases.As the result, interconnect contributes50% of total delay in 0.35μm technology andis expected to contribute up to 70% in 0.25μm.Interconnectdelay on chip dominates the gate delay.Largeheight to width ratio, 2:1 in 1998 and 2.5:1 in 2001,and many interconnect layers, 5-8 in 1998 and 8-10 in2001, make lateral coupling increasingly more significantthan coupling to ground.Cross talk not only causes awrong logic result on one particular clock cycle, but alsoleads to a different timing behavior of neighboring lines.Delay cannot be calculated accurately without takingcross talk into account.Not to mention conformal dielectricsand non-orthogonal conductor cross sections.The above technology shift calls for 3D parasitic extraction.However, it is prohibitively expensive to extractevery net in 3D; in fact, it is not necessary to do so.Beforepresenting the multi-tiered extraction methodology,I will first classify various extracion methodologies.
Caution: the differences between CT and ACT may be larger (and smaller) than they appear.

Abstract Hofmann, Asmundson, & Beck (2013--this issue) offer an overview of cognitive-behavior therapy (CBT) as well as its similarities and differences from so-called “third-generation” behavior therapies, particularly Acceptance and Commitment Therapy (ACT). In this commentary we suggest that CBT is most accurately viewed as a broad family of distinct psychotherapy models that includes the traditional Beckian approach of cognitive therapy as well as newer acceptance-based approaches such as ACT. We argue that Hofmann, Asmundson, & Beck's discussion of the differences in CT and ACT's view of the causal role of cognition lacks clarity. For instance, the behavior analytic framework of ACT does not categorically deny any causal role of cognitions in behavioral and emotional responses. Similarly, we disagree with the authors’ contention that CT utilizes primarily antecedent-focused and ACT employs response-focused emotion regulation strategies. In addition, we take the view that the empirical evidence for CT, although very impressive, does not reduce the impetus to innovate. We object to some of Hofmann, Asmundson, & Beck's interpretation of component and mediational analyses and argue that the field does, in fact, need to question CT's postulated mechanism of action (i.e., cognitive change), both on theoretical and pragmatic grounds. At the same time, although preliminary research on ACT is promising, we suggest that its proponents need to be appropriately humble in their claims. In particular, like CT, ACT cannot yet make strong claims that its unique and theory-driven intervention components are active ingredients in its effects. We conclude that the fundamental differences between CT and ACT are philosophical and theoretical rather than technological.
Adrenergic modulation of splenic macrophage cytokine release in polymicrobial sepsis

Enhanced adrenergic stimulation and catecholamine release are important components of the pathophysiology of sepsis. Under physiological conditions, adrenergic stimulation has been shown to be a negative regulator of proinflammatory cytokine production through increasing IL-10 production. Here we have investigated if adrenergic stimulation similarly inhibits TNF-alpha and IL-6 production by splenic macrophages isolated from a polymicrobial sepsis model. Male B(6)D(2)F(1) mice were subjected to sham (S), laparotomy (Lap), and cecal ligation and puncture (CLP) under anesthesia. Splenic macrophages were isolated 72 h after the initial injury and were stimulated with endotoxin (LPS) in the presence and absence of epinephrine. Compared with S and Lap, splenic macrophages from the CLP group produced significantly less TNF-alpha and IL-6 and more IL-10 when stimulated with LPS. Macrophage cultures from CLP animals incubated with either epinephrine or IL-10 for 2 h had significantly reduced TNF-alpha and IL-6 release in response to LPS. However, similar cultures pretreated with IL-10 antibody before the addition of exogenous epinephrine failed to reverse the attenuation of LPS-stimulated cytokines. Pretreatment of macrophage cultures with beta(2)- (ICI-118551) but not beta(1)-adrenergic (atenolol) receptor antagonists reversed the epinephrine-mediated cytokine attenuation following LPS treatment. Data are also presented that demonstrate the involvement of protein kinase A activation with adrenergic agonist but not with IL-10 stimulation. Taken together, these findings suggest that adrenergic mechanisms may influence peripheral tissue macrophage inflammatory cytokine response following trauma and sepsis, independent of the effects of IL-10.
INDICATIONS FOR EARLY HÆMODIALYSIS IN MULTIPLE TRAUMA

Abstract Renal function in 751 cases of multiple trauma was studied to define a level of function compatible with ultimate survival. Established definitions of renal failure were ignored. A daily renal index was calculated using urine volume, serum-creatinine, and blood-urea-nitrogen (B.U.N.). The data for 3600 patient-days were analysed on a computer. Probability of survival was less than 0.1 in patients with a creatinine >4 mg. per 100 ml. or a B.U.N. >80 mg. per 100 ml. or a renal index >3 on one occasion or >2 on two consecutive days. The renal index provided an earlier and more accurate prognosis in a significant number of patients when compared with the other variables. The impairment of renal function associated with death in the patient studied is considerably less than currently accepted criteria for haemodialysis. Dialysis to within the levels shown to be compatible with survival offers a method of reducing the high mortality. Clinical application of the renal index as an indication for early haemodialysis in major trauma is proposed.
Trends in otitis media-related health care use in the united states, 2001-2011

Importance Otitis media (OM) is a leading cause of pediatric health care visits and the most frequent reason children consume antibiotics or undergo surgery. During recent years, several interventions have been introduced aiming to decrease OM burden. Objective To study the trend in OM-related health care use in the United States during the pneumococcal conjugate vaccine (PCV) era (2001-2011). Design, Setting, and Participants An analysis of an insurance claims database of a large, nationwide managed health care plan was conducted. Enrolled children aged 6 years or younger with OM visits were identified. Main Outcomes and Measures Annual OM visit rates, OM-related complications, and surgical interventions were analyzed. Results Overall, 7.82 million unique children (5.51 million child-years) contributed 6.21 million primary OM visits; 52% were boys and 48% were younger than 2 years. There was a downward trend in OM visit rates from 2004 to 2011, with a significant drop that coincided with the advent of the 13-valent vaccine (PCV-13) in 2010. The observed OM visit rates in 2010 (1.00/child-year) and 2011 (0.81/child-year) were lower than the projected rates based on the 2005-2009 trend had there been no intervention (P Conclusions and Relevance There was an overall downward trend in OM-related health care use from 2001 to 2011. The significant reduction in OM visit rates in 2010-2011 in children younger than 2 years coincided with the advent of PCV-13. Although tympanic membrane perforation/otorrhea rates steadily increased during that period, mastoiditis and ventilating tube insertion rates decreased in the last years of the study.
Eseroline, a metabolite of physostigmine, induces neuronal cell death

Abstract The toxic effects of physostigmine, an anticholinesterase drug, and its metabolite eseroline were investigated in three neuronal cell culture systems, mouse neuroblastoma N1E-115, rat glioma C6, and neuroblastoma-glioma hybrid NG 108-15. Physostigmine and eseroline (0.5 m m ) elicited a time-dependent leakage of lactic acid dehydrogenase (LDH) from all three cell types. An increased release of [ 14 C]adenine nucleotides was also detected from cells when they were prelabeled with [ 14 C]adenine. Eseroline was comparatively more toxic than the parent compound, physostigmine. Eseroline elicited a dose- and time-dependent leakage of LDH and release of adenine nucleotides from the neuronal cells. A nonneuronal cell line, rat liver ARL-15, was comparatively the most resistant cell type to eseroline toxicity. The concentrations of eseroline needed for 50% release of adenine nucleotides or 50% leakage of LDH from NG-108-15 and NIE-115 cells in 24 hr ranged from 40 to 75 μ m . The concentrations of eseroline needed to obtain similar responses in C6 and ARL-15 cells were much higher and ranged from 80 to 120 μ m . Phase contrast microscopy showed extensive damage to three neuronal cell lines at concentrations of eseroline as low as 75 μ m . The loss of ATP from N1E-115 cells exceeded 50% when they were treated with 0.3 m m eseroline for 1 hr-at which time the leakage of LDH was not detectable. It seems that eseroline causes neuronal cell death by a mechanism involving loss of cell ATP. Thus, the formation of eseroline may contribute to the toxic effect of physostigmine.
Empirical Analysis of the Learning Curve Principle in Prestressed Concrete Piles

The principle of learning curves can be applied in construction for the prediction of the time/cycle of future work, work performance levels, and other performance measures. Learning curve principles can be effectively utilized in litigation cases where production is compromised by delays. The objective of this study was to determine if learning curves could be used to accurately predict the production efforts of future units by applying the principles to the prefabrication and driving of prestressed concrete piles. The individual time to cast each of the concrete piles was recorded and used to compute the cumulative average time ( CATN ) to fabricate the concrete piles. The data were used to compute the learning rate (ϕ) and the theoretical time to complete the first unit ( Kc ) . From this information, predictions were made as to the amount of effort to fabricate future piles. The results showed that the pile fabrication crew improved its learning throughout the pile fabrication effort, but this improve...
Cervical Cancer Prevention Knowledge and Abnormal Pap Test Experiences Among Women Living with HIV/AIDS

Cervical cancer prevention knowledge deficits persist among women living with HIV/AIDS (WLHA) despite increased risk of developing cervical dysplasia/cancer. We examined associations between WLHA’s cervical cancer prevention knowledge and abnormal Pap test history. We recruited 145 urban and rural WLHA from Ryan White-funded clinics and AIDS service organizations located in the southeastern USA between March 2011 and April 2012. For this analysis, women who reported a history of cervical cancer (n = 3) or had a complete hysterectomy (n = 14) and observations with missing data (n = 22) were excluded. Stata/IC 13 was used to perform cross-tabulations and chi-squared tests. Our sample included 106 predominantly non-Hispanic Black (92 %) WLHA. Mean age was 46.3 ± 10.9 years. Half (50 %) had ≤ high school education. One third (37 %) had low health literacy. The majority (83 %) had a Pap test <1 year ago, and 84 % knew that WLHA should have a Pap test every year, once two tests are normal. Many (68 %) have had an abnormal Pap test. Abnormal Pap test follow-up care knowledge varied. While 86 % knew follow-up care could include a repeat Pap test, only 56 % knew this could also include an HPV test. Significantly, more women who had an abnormal Pap test knew follow-up care could include a biopsy (p = 0.001). For WLHA to make informed/shared decisions about their cervical health, they need to be knowledgeable about cervical cancer care options across the cancer control continuum. Providing WLHA with prevention knowledge beyond screening recommendations seems warranted given their increased risk of developing cervical dysplasia/neoplasia.
Dewex: An Exploration Facility for Enabling the Deep Web Integration

In this demo, we present Dewex, an exploration facility for answering questions like T1-TA, running on repository of over 30,000 real sources. The main technical contributions of this demo are: as our system, we present a novel facility for exploring the deep Web; as our solution, we propose a schematic metadata based source modeling, and a generalized search mechanism to compute associativity in metadata graph; and in our realization, to enable online exploration, we propose to speed up computation using matrix optimization.
Progress in prevention of infectious disease.

Abstract Current issues in preventing infectious diseases and their implications for the future are examined, looking broadly at technologies, program strategies, and the growing influence of public and professional attitudes and perceptions in maintaining and achieving infectious disease control. It is concluded that the technologies to control infectious diseases are available, implementation of delivery programs is feasible, and current attitudes of public and professions dampen but should not impede progress. The need for distributing the benefits of available preventive medical technology to the developing world is obvious, but achievements will be difficult and costly. It is equally important for the economically developed countries that have achieved successes in infectious disease prevention to sustain their progress and confront the concerns of public compliance, liability, management, and program support which threaten to hinder progress. Obviously, the needs must be clearly enunciated and the problems solved in order for the job of infectious disease prevention to be done.
Isolation of novel ribozymes that ligate AMP-activated RNA substrates

BACKGROUND: The protein enzymes RNA ligase and DNA ligase catalyze the ligation of nucleic acids via an adenosine-5'-5'-pyrophosphate 'capped' RNA or DNA intermediate. The activation of nucleic acid substrates by adenosine 5'-monophosphate (AMP) may be a vestige of 'RNA world' catalysis. AMP-activated ligation seems ideally suited for catalysis by ribozymes (RNA enzymes), because an RNA motif capable of tightly and specifically binding AMP has previously been isolated. RESULTS: We used in vitro selection and directed evolution to explore the ability of ribozymes to catalyze the template-directed ligation of AMP-activated RNAs. We subjected a pool of 10(15) RNA molecules, each consisting of long random sequences flanking a mutagenized adenosine triphosphate (ATP) aptamer, to ten rounds of in vitro selection, including three rounds involving mutagenic polymerase chain reaction. Selection was for the ligation of an oligonucleotide to the 5'-capped active pool RNA species. Many different ligase ribozymes were isolated; these ribozymes had rates of reaction up to 0.4 ligations per hour, corresponding to rate accelerations of approximately 5 x10(5) over the templated, but otherwise uncatalyzed, background reaction rate. Three characterized ribozymes catalyzed the formation of 3'-5'-phosphodiester bonds and were highly specific for activation by AMP at the ligation site. CONCLUSIONS: The existence of a new class of ligase ribozymes is consistent with the hypothesis that the unusual mechanism of the biological ligases resulted from a conservation of mechanism during an evolutionary replacement of a primordial ribozyme ligase by a more modern protein enzyme. The newly isolated ligase ribozymes may also provide a starting point for the isolation of ribozymes that catalyze the polymerization of AMP-activated oligonucleotides or mononucleotides, which might have been the prebiotic analogs of nucleoside triphosphates.
Discrete magnitude-squared channel modeling, equalization, and detection for volume holographic storage channels

As storage density increases, the performance of volume holographic storage channels is degraded, because intersymbol interference and noise also increase. Equalization and detection methods must be employed to mitigate the effects of intersignal interference and noise. However, the output detector array in a holographic storage system detects the intensity of the incident light's wave front, leading to loss of sign information. This sign loss precludes the applicability of conventional equalization and detection schemes. We first address channel modeling under quadratic nonlinearity and develop an efficient model named the discrete magnitude-squared channel model. We next introduce an advanced equalization method called the iterative magnitude-squared decision feedback equalization (IMSDFE), which takes the channel nonlinearity into account. The performance of IMSDFE is quantified for optical-noise-dominated channels as well as for electronic-noise-dominated channels. Results indicate that IMSDFE is a good candidate for a high-density, high-intersignal-interference volume holographic storage channel.
Multispectral Mapper: Imaging Spectroscopy As Applied To The Mapping Of Earth Resources

An instrument concept that uses solid-state array imaging has been developed for a future land observing system. The design concept is responsive to a variety of use needs and provides improved capabilities over the planned Landsat Thematic Mapper. A comparison of the differing approaches to the instrument design was made, resulting in the selection of a concept which uses a spectrograph coupled to a line-array imager to provide simultaneous spatial and spectral resolution. The design provides an inherent solution to the problem of achieving precise registration among the spectral bands. Data processing on the focal plane is used to select the spectral bands and their band widths. Onboard capabilities include radiometric correction, selection of instantaneous field-of-view and swath width, and data compression.
Simple Method For Designing Lenses

A simple method is described for quickly and easily designing high-performance optical systems. It involves little iteration, if any, and requires neither a computer nor extensive hand calculations. The systematic application of this design method allows one to construct configurations where the function of every surface is clearly understood. As a result, new design configurations tend to suggest themselves to the designer. This insight, which is an integral part of the design method to be described, also makes it clear how to compound designs so as to extend the f/# and/or field of view over which high performance is obtained. Although the design method only uses well-known principles of aberration control, it combines them and systematically applies them in a particular way that has not gained the wide use it merits. Several design examples illustrate how this design method is applied. They include a telephoto lens, an inverse telephoto lens, a fisheye type lens and a catadioptric system.
Calcareous nannofossil assemblage changes across the Paleocene–Eocene Thermal Maximum: Evidence from a shelf setting

article i nfo Biotic response of calcareous nannoplankton to abrupt warming across the Paleocene/Eocene boundary re- flects a primary response to climatically induced parameters including increased continental runoff of fresh- water, global acidification of seawater, high sedimentation rates, and calcareous nannoplankton assemblage turnover. We identify ecophenotypic nannofossil species adapted to low pH conditions (Discoaster anartios, D. araneus, Rhomboaster spp.), excursion taxa adapted to the extremely warm climatic conditions (Bomolithus supremus and Coccolithus bownii), three species of the genus Toweius (T. serotinus, T. callosus, T. occultatus) adapted to warm, rather than cool, water conditions, opportunists adapted to high productivity conditions (Coronocyclus bramlettei, Neochiastozygus junctus), and species adapted to oligotropic and/or cool-water con- ditions that went into refugium during the PETM (Zygrablithus bijugatus, Calcidiscus? parvicrucis and Chiasmolithus bidens). Discoaster anartios was adapted to meso- to eutrophic, rather than oligotrophic, condi- tions. Comparison of these data to previous work on sediments deposited on shelf settings suggests that local conditions such as high precipitation rates and possible increase in major storms such as hurricanes resulted in increased continental runoff and high sedimentation rates that affected assemblage response to the PETM. Published by Elsevier B.V.
Mining temporal relationships among categories

Temporal text mining deals with discovering temporal patterns in text over a period of time. A Theme Evolution Graph (TEG) is used to visualize when new themes are created and how they evolve with respect to time. TEG, however, does not represent relationships among themes (or categories) that share same timestamp. We focus on identifying such relationships and represent them in Relationship Evolution Graph (REG). We favorably compare passage misclassification and association rule mining with three existing approaches, namely KL divergence (KLD), Consistent bipartite spectral co-partitioning graph (CBSCG) and document misclassification. Our evaluations indicate that association rule mining approach statistically significantly (99% confidence) outperforms the other existing approaches, while passage misclassification approach is the second most effective approach.
Word, Like Fire: Maria Stewart, the Bible, and the Rights of African Americans

Scholars have underscored the importance of early African American abolitionist and woman's rights advocate Maria Stewart as they delved into the origins and intersection of both movements. Yet Ste...
The clinical implications of ß-lactamases

Summary The clinical importance of s-lactamases was recognized shortly after the clinical use of penicillins. This clinical importance has not diminished over the past fifty years, but instead has increased. It is clear that s-lactamases will continue to be one of the most important microbial resistance mechanisms against s-lactam agents. Clinicians need to appreciate this resistance mechanism. Accordingly, a review of the most important aspects of this form of resistance have been presented in three earlier issues of the newsletter.
Reduced habituation in patients with schizophrenia

Background Neural habituation, the decrease in brain response to repeated stimulation, is a basic form of learning. There is strong evidence for behavioral and physiological habituation deficits in schizophrenia, and one previous study found reduced neural habituation within the hippocampus. However, it is unknown whether neural habituation deficits are specific to faces and limited to the hippocampus. Here we studied habituation of several brain regions in schizophrenia, using both face and object stimuli. Post-scan memory measures were administered to test for a link between hippocampal habituation and memory performance.
Transmission properties of tapered air-core photonic bandgap fibers

Fiber tapers have found a wide range of important applications in communication and sensing, including narrow-band filters, mode-matching between waveguides, evanescent mode-coupling and fused couplers. Applying these taper-based technologies to air-core photonic bandgap fibers (PBFs) is very appealing because it would enable creating these same components directly in air-core fibers. Although there have been several studies of tapers in solid-core microstructured fibers, the transmission properties of tapered air-core photonic-bandgap fibers have not yet been studied. In this work, we report on the fabrication and testing of tapered air-core photonic-bandgap fibers. Our motivation in this work was to study the basic transmission properties of PBF bitapers in the bandgap region, and in particular, to see how the overall transmission was impacted by the taper, e.g., whether the taper induced resonant coupling to one or more cladding modes. Our experimental results indicate that air-core PBFs are highly sensitive to tapering, and unlike conventional single-mode telecommunication fibers, even a small tapering ratio results in significant modal interference in the transmission spectrum. Furthermore, we found out that the mechanical silica support surrounding the holey region of the PBF contributes as a lossy Fabry-Perot resonator to the observed transmission properties.
Diversity dynamics of Miocene mammals in relation to the history of tectonism and climate

Continental biodiversity gradients result not only from ecological processes, but also from evolutionary and geohistorical processes involving biotic turnover in landscape and climatic history over millions of years. Here, we investigate the evolutionary and historical contributions to the gradient of increasing species richness with topographic complexity. We analysed a dataset of 418 fossil rodent species from western North America spanning 25 to 5 Ma. We compared diversification histories between tectonically active (Intermontane West) and quiescent (Great Plains) regions. Although diversification histories differed between the two regions, species richness, origination rate and extinction rate per million years were not systematically different over the 20 Myr interval. In the tectonically active region, the greatest increase in originations coincided with a Middle Miocene episode of intensified tectonic activity and global warming. During subsequent global cooling, species richness declined in the montane region and increased on the Great Plains. These results suggest that interactions between tectonic activity and climate change stimulate diversification in mammals. The elevational diversity gradient characteristic of modern mammalian faunas was not a persistent feature over geologic time. Rather, the Miocene rodent record suggests that the elevational diversity gradient is a transient feature arising during particular episodes of Earth's history.
Using computer technology to support cost-effective paperless interactive technical data

The technology is available today to provide technical data in an economical paperless environment. The presentation of technical data must support having a system that is user-friendly, flexible, comprehensive, and quickly accessed. This automated system should also support the Congressional Continuous Acquisition and Life-cycle Support (CALS) mandate of establishing paperless environments. This paper deals specifically with placing the volumes of hardcopy technical data into digital format to support weapon system maintenance requirements. This paper addresses the benefits and liabilities of specific computer technology-related alternatives available for establishing a cost-effective paperless interactive technical data system. The software and hardware products identified in this paper are provided as examples and are not to be considered as actual product endorsements. >
Chromatin remodeling: a novel mechanism of psychotropic drug action.

Regulation of gene expression is known to contribute to the long-term adaptations underlying the effects of psychotropic drugs, including the actions of antidepressants and drugs of abuse in behavioral models. However, the precise molecular events that are required for modification of chromatin and that underlie gene repression or activation have not been elucidated. Recent reports, including the article by Cassel et al. (p. 487) in this issue of Molecular Pharmacology, address this question and demonstrate that psychotropic drugs modify specific methyl-CpG-binding proteins that control histone acetylation and gene expression.
Stability of (Mg,Fe)SiO3 perovskite and the structure of the lowermost mantle

Thermodynamic analysis shows that (Mg,Fe)SiO3 perovskite is stable throughout the likely pressure, temperature and compositional regime of the Earth's mantle. The breakdown of perovskite to its constituent oxides appears unlikely, even under the extreme conditions of the core-mantle boundary. This reaction had been proposed to reconcile estimates of silicate melting with seismic observation and proposed geotherms.
Innovative thin film deposition technologies enabling new materials and new device integration roadmaps

Innovative thin film deposition technologies play a key role in new device scaling strategies that are increasingly based on the use of new materials and 3D approaches. Smart tailor-made equipment solutions have enabled processes that were previously considered impossible for volume manufacturing. Examples of atomic layer deposition and epitaxy techniques for logic and memory devices will be presented as well as spin-offs to applications in solar cells and hard disks.
The Set and Function Approach to Modeling Authorization in Distributed Systems

We present a new model that provides clear and precise semantics for authorization. The semantics is independent from underling security mechanisms and is separate from implementation. The model is capable of representing existing access control mechanisms. Our approach is based on set and function formalism. We focus our attention on identifying issues and use our model as a general basis to investigate the issues.
hnRNP A1 interacts with the genomic and subgenomic RNA promoters of Sindbis virus and is required for the synthesis of G and SG RNA

Sindbis virus (SV) is the prototype of alphaviruses which are a group of widely distributed human and animal pathogens. Heterogeneous nuclear ribonucleoprotein (hnRNP) A1 is an RNA-binding protein that shuttles between the nucleus and the cytoplasm. Our recent studies found that hnRNP A1 relocates from nucleus to cytoplasm in Sindbis virus (SV)-infected cells. hnRNP A1 binds to the 5' UTR of SV RNA and facilitates the viral RNA replication and translation. Making use of standard molecular techniques, virology methods and an in vitro system developed by our lab to assess the role of hnRNP A1 in SV positive strand RNA synthesis. hnRNP A1 interacted with the genomic (G) and subgenomic (SG) RNA promoters. Knockdown of hnRNP A1 resulted in markedly decrease in the synthesis of G and SG RNA both in infected cells and in vitro. Our study provides the first direct evidence that hnRNP A1 actively participates in viral RNA replication and is required for the synthesis of G and SG RNA.