cssi/SciSciGPT-SciSciNet huggingface dataset:
Room temperature synthesis of PbSe quantum dots in aqueous solution: stabilization by interactions with ligands

An aqueous route of synthesis is described for rapid synthesis of lead selenide quantum dots (PbSe QDs) at room temperature in an attempt to produce water-soluble and stable nanocrystals. Several thiol-ligands, including thioglycolic acid (TGA), thioglycerol (TGC), 3-mercaptopropionic acid (MPA), 2-mercaptoethylamine hydrochloride (MEA), 6-mercaptohexanoic acid (MHA), and L-cysteine (L-cys), were used for capping/stabilization of PbSe QDs. The effects of the ligands on the stability of PbSe QDs were evaluated for a period of two months at room temperature under normal light conditions and at 4 °C in the dark. The TGA- and MEA-capped QDs exhibited the highest stability prior to purification, almost two months when kept in the dark at 4 °C. However, the stability of TGA-capped QDs was reduced substantially after purification to about 5 days under the same conditions, while MEA-capped QDs did not show any significant instability. The stabilization energies of Pb–thiolate complexes determined by theoretical DFT simulations supported the experimental results. The PbSe QDs capped with TGA, MPA and MEA were successfully purified and re-dispersed in water, while those stabilized with TGC, MHA and L-cys aggregated during purification attempts. The purified PbSe QDs possess very susceptible surface resulting in poor stability for about 30–45 min after re-dispersion in water. In the presence of an excess of free ligand, the stability increased up to 5 days for TGA-capped QDs at pH 7.19, 9–12 days for MPA-capped QDs at pH 7.3–7.5 and 45–47 days for MEA-capped QDs at pH 7.35. X-Ray diffraction (XRD) results showed that the QDs possess a cubic rock salt structure with the most intense peaks located at 2θ = 25.3° (200) and 2θ = 29.2° (100). TEM images showed that the size of the QDs ranges between 5 and 10 nm. ICP-MS results revealed that Pb : Se ratios were 1.26, 1.28, 3.85, 1.18, and 1.31 for the QDs capped with TGA, MPA, MEA, L-cys, and TGC, respectively. The proposed method is inexpensive, simple and utilizes environmentally friendly chemicals and solvents.
3D lithographically fabricated nanoliter containers for drug delivery

Lithographic patterning offers the possibility for precise structuring of drug delivery devices. The fabrication process can also facilitate the incorporation of advanced functionality for imaging, sensing, telemetry and actuation. However, a major limitation of present day lithographic fabrication is the inherent two-dimensionality of the patterning process. We review a new approach to construct three dimensional (3D) patterned containers by lithographically patterning two dimensional (2D) templates with liquefiable hinges that spontaneously fold upon heating into hollow polyhedral containers. The containers have finite encapsulation volumes, can be made small enough to pass through a hypodermic needle, and the 3D profile of the containers facilitates enhanced diffusion with the surrounding medium as compared to reservoir systems fabricated in planar substrates. We compare the features of the containers to those of present day drug delivery systems. These features include ease of manufacture, versatility in size and shape, monodisperse porosity, ability for spatial manipulation and remote triggering to release drugs on-demand, the incorporation of electronic modules, cell encapsulation, biocompatibility and stability. We also review possible applications in drug delivery and cell encapsulation therapy (CET). The results summarized in this review suggest a new strategy to enable construction of “smart”, three dimensional drug delivery systems using lithography. © 2007 Elsevier B.V. All rights reserved.
Comparison of replication strategies for content availability in C2P2 networks

This study investigates alternative continuous media replication techniques and their impact on content availability in a mobile car-to-car peer-to-peer (C2P2) network of devices. Using aggregate availability latency as a metric, we compare a simple random replication mechanism with a family of techniques that compute the degree of replication for each title based on its popularity, i.e., frequency of access. We use a simulation study along with some supporting analytical analysis for this comparison. Obtained results demonstrate the following key lesson. When total storage capacity of the network is significantly larger than the clip repository size, a random replication technique is sufficient. Otherwise, there is a large parameter space where the frequency-based replication schemes provide superior performance.
Propaganda as an environmental justice issue

Propaganda has a long history in the industrialised North as a disreputable method of communication and persuasion. I adopt the definition of ‘propaganda’ elaborated by Ross (2002). The people of Kivalina are being forced to relocate their village due to the effects of climate change. This is an instance of environmental injustice. They maintain that certain actions of fossil fuel companies, amounting to civil conspiracy, are at least in part responsible for these effects. I argue that these actions of the fossil fuel companies are propaganda. Accordingly, understanding propaganda is crucial for the environmental justice movement
Der Sphärensatz in der Riemannschen Geometrie

Das Zusammenspiel zwischen Krummung und Topologie einer Riemannschen Mannigfaltigkeit ist eine der zentralen Fragen in der globalen Differentialgeometrie. Ein klassisches Ergebnis von Heinz Hopf besagt, das jede kompakte, einfach zusammenhangende Mannigfaltigkeit mit konstanter Krummung 1 isometrisch zur runden Sphare ist. Inspiriert durch dieses Ergebnis stellte Hopf die Frage, ob eine kompakte, einfach zusammenhangende Mannigfaltigkeit, deren Schnittkrummungen im Intervall [1−e,1] liegen, topologisch eine Sphare ist. In ersten Teil dieser Arbeit beschreiben wir die Geschichte dieses Fragenkomplexes. Im zweiten Teil diskutieren wir den Differenzierbaren Spharensatz, sowie einige verwandte Ergebnisse. Die Beweise verwenden eine Vielzahl unterschiedlicher Methoden, darunter Stabilitatsargumente fur Geodaten und Minimalflachen, sowie die Ricci-Flus-Methode von Richard Hamilton. Fur die detaillierten Argumente sei auf die Monographie des Authors (Graduate Studies in Mathematics, Bd. 111, Amer. Math. Soc., 2010) verwiesen.
Thermal conductance of Andreev interferometers.

The thermal transport properties of proximity-coupled normal metals have attracted interest recently [1‐3], spurred by recent measurements of the thermopower SA of Andreev interferometers [4 ‐6], which are loops in which one arm is fabricated from a superconductor (S), and the second arm from a normal metal (N). In these experiments, which include some of our own, the thermopower was found to oscillate periodically as a function of applied magnetic flux, with a fundamental period corresponding to � 0 � h=2e. In spite of some recent theoretical attempts [1], these experimental results have not been explained satisfactorily. Given this problem, we have more recently turned our attention to measurements of the thermal conductance G T of proximity-coupled systems [7], which are more easily calculated in the quasiclassical approximation. Bezuglyi and Vinokur [2] recently discussed G T for a NSN sandwich where the size of S is smaller than the coherence length. They found a strong suppression of G T with decreasing temperature T and oscillations with the applied flux � . However, this behavior was determined primarily by the modification of the thermal conductance of the superconducting component of the sandwich arising from proximity to the normal metal, an inverse proximity effect. In this Letter, we calculate G T arising from a normal-metal proximity effect for two types of Andreev interferometers relevant to the experiments, the ‘‘house‘‘ geometry, and the ‘‘parallelogram‘‘ geometry shown in Fig. 1. Our intent is to determine the effect of sample geometry and finite NS interface resistance on G T . As before, we find that the normalized thermal conductance G T =G T of these devices decreases as the temperature is reduced below the transition temperature of the superconductor [2], but saturates at a finite value that depends on the transparency of the NS interface and the distance of the NS interfaces from the path of the thermal current. The thermal conductance is highly nonlinear, varying with the heat current I T approximately as ����� T p for intermediate values of I T . Finally, G T oscillates periodically with an applied magnetic flux with a fundamental period of h=2e and an amplitude corresponding to a few percent of G T , with the amplitude of the oscillations in the house geometry being in general larger than those in the parallelogram geometry. For both the house and the parallelogram geometries, the oscillations in G T are symmetric in the applied flux. The suppression in G T is directly related to the suppression in the density of states in the path of the thermal current. Our starting point is the kinetic equations for the nonequilibrium distribution functions in the diffusive limit [1,8‐10]:
Ranks of indecomposable modules over one-dimensional rings, II

Abstract We consider finitely generated torsionfree modules over one-dimensional, reduced, commutative, Noetherian rings with finite normalization. Among these rings for which, locally, indecomposable modules have all ranks at minimal primes ≤1, does there exist a uniform global bound? The answer is “no” unless the ranks of the modules are restricted to be nearly constant. Given any positive integer n , there exists such a semilocal ring and an indecomposable module whose ranks are all between n and 2 n − 1. On the other hand, for n ≥3 and such a ring, every finitely generated torsionfree module with ranks between n and 2 n − 2 decomposes nontrivially.
Role of Chains in the Formation of Extended Framework Tin(II) Phosphates and Related Materials

The reactions of tin(II) chloride with phosphonic and phosphinic acids under hydrothermal conditions result in structures with varying dimensionalities. The synthesis and characterization of eight ...
Full-state derivative feedback control based on the reciprocal state space framework using smart materials

In this research, a real-time simulation of full state- derivative feedback control using acceleration measurements is presented. A new optimal control design algorithm based on non-standard performance indices in the 'Reciprocal State Space' framework is employed to design controllers and observers. A piezoelectric material (PZT) laminated cantilevered steel beam with an accelerometer is selected as a test bed. The system is modeled utilizing a multi-layered integrated finite element method with four degree of freedom, one-dimensional, bending elements. The resulting model, presented in generalized coordinates, is transformed to real orthogonal modal coordinates and a reduced order model is developed. Simulated results are provided in multiple formats.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Toward ultimate miniaturization of high Q silicon traveling-wave microresonators.

High Q traveling-wave resonators (TWR)s are one of the key building block components for VLSI Photonics and photonic integrated circuits (PIC). However, dense VLSI integration requires small footprint resonators. While photonic crystal resonators have shown the record in simultaneous high Q (~105-106) and very small mode volumes; the structural simplicity of TWRs has motivated many ongoing researches on miniaturization of these resonators with maintaining Q in the same range. In this paper, we investigate the scaling issues of silicon traveling-wave microresonators down to ultimate miniaturization levels in SOI platforms. Two main constraints that are considered during this down scaling are: 1) Preservation of the intrinsic Q of the resonator at high values, and 2) Compatibility of resonator with passive (active) integration by preserving the SiO2 BOX layer (plus a thin Si slab layer for P-N junction fabrication). Microdisk and microdonut (an intermediate design between disk and ring shape) are considered for high Q, miniaturization, and single-mode operation over a wide wavelength range (as high as the free-spectral range). Theoretical and experimental results for miniaturized resonators are demonstrated and Q's as high as ~105 for resonators as small as 1.5 μm radius are achieved.
Deterministic representation of probabilistic systems by ergodic machines

Homomorphic simplification is one way of defining valid simplication of deterministic models. To allow the use of similar techniques for probabilistic systems, we introduce the concept of an ergodic machine. An ergodic machine is a specification for a deterministic system and it represents and associated probabilistic system when viewed properly. The probabilistic features arise by using an ergodic transformation on a “hidden” partial state space. An ergodic transformation can be thought of as an ideal random number generator. In this paper, we develop the concepts of ergodic machines necessary for faithfully representing probabilistic systems and make connections to markov chains and pseudo random number generators.
Global optimization for scheduling refinery crude oil operations

In this work we present an outer-approximation algorithm to obtain the global optimum of a nonconvex mixed-integer nonlinear programming (MINLP) model that is used to represent the scheduling of crude oil movement at the front-end of a petroleum refinery. The model relies on a continuous time representation making use of transfer events. The proposed algorithm focuses on effectively solving a mixed-integer linear programming (MILP) relaxation of the nonconvex MINLP to obtain a rigorous lower bound (LB) on the global optimum. Cutting planes derived by spatially decomposing the network are added to the MILP relaxation of the original nonconvex MINLP in order to reduce the solution time for the MILP relaxation. The solution of this relaxation is used as a heuristic to obtain a feasible solution to the MINLP which serves as an upper bound (UB). The lower and upper bounds are made to converge to within a specified tolerance in the proposed outer-approximation algorithm. On applying the proposed technique to test examples, significant savings are realized in the computational effort required to obtain provably global optimal solutions.
Interleukin 17 Regulates Mer Tyrosine Kinase–Positive Cells in Pseudomonas aeruginosa Keratitis

Purpose To determine if IL-17 regulates Mer tyrosine kinase-positive (MerTK+) cells in Pseudomonas aeruginosa keratitis. Methods Interleukin 17 was tested in normal and infected cornea of susceptible C57BL/6 and resistant BALB/c mice. The latter were treated with recombinant mouse (rm) IL-17; both groups were treated with IL-17 neutralizing antibody. Mice were infected, and clinical score, PCR, ELISA, and myeloperoxidase (MPO) assays tested expression of proinflammatory and anti-inflammatory mediators and polymorphonuclear neutrophilic leukocyte (PMN) infiltrate. Fas and Fas ligand (FasL) protein levels were assessed in both mouse strains, while MerTK+ cells were examined by immunostaining and cell sorting before and after IL-17 neutralization. Results The IL-17 mRNA and protein were higher in C57BL/6 versus BALB/c cornea after infection. The rmIL-17 treatment of BALB/c mice modified proinflammatory and anti-inflammatory mediators, but clinical score and MPO assay revealed no differences. However, only BALB/c mice treated with IL-17 neutralizing antibody showed increased disease, macrophage inflammatory protein (MIP) 2, and MPO levels. Fas and FasL protein levels, elevated earlier in BALB/c versus C57BL/6 mice, correlated with significantly more MerTK+ cells in BALB/c cornea at 3 days after infection. Neutralization of IL-17 in C57BL/6 mice elevated MerTK+ cells, while similar treatment of BALB/c mice significantly decreased them. Conclusions These data provide evidence that IL-17 expression is higher in C57BL/6 versus BALB/c cornea after infection and that the latter group has more MerTK+ cells. Exogenous rmIL-17 failed to shift the disease response in resistant mice, but its neutralization resulted in worsened disease and reduced MerTK+ cells. Neutralization of IL-17 in C57BL/6 mice increased MerTK+ cells but did not dramatically shift the disease response.
Preparing to Replace the Official Horizontal and Vertical Datums in the United States: Federal Geospatial Summit on Improving the National Spatial Reference System; Silver Spring, Maryland, 11–12 May 2010

The National Spatial Reference System (NSRS) contains both the official “horizontal” and “vertical” datums of the United States: the North American Datum of 1983 (NAD83) and the North American Vertical Datum of 1988 (NAVD88). Horizontal datums provide reference latitude and longitude on Earth's surface; vertical datums are used for describing elevation. The responsibility for defining, maintaining, and providing access to these datums falls to the National Geodetic Survey (NGS), an office within the National Oceanic and Atmospheric Administration (NOAA). These datums were created to correct deficiencies in the previous (1920's era) datums. Still, they relied almost exclusively on terrestrial surveying and the use of passive marks for their realization. Once the Global Positioning System (GPS) and other space geodetic techniques were widely operational, some significant issues became apparent. First, NAD83 has a nongeocentricity (i.e., its origin differs from the known center of Earth's mass) of approximately 2.2 meters. Second, the use of NAVD88's unmonitored passive control benchmarks to determine elevations lacks critical vertical velocity information. Additionally, the zero-elevation surface of NAVD88 is now known to be biased (50 centimeters) and tilted (2 meters from Florida to Alaska) relative to the geoid.
Optimization of dc SQUID voltmeter and magnetometer circuits

We calculate the signal-to-noise ratio in a dc SQUID system as a function of source impedance, taking into account the effects of current and voltage noise sources in the SQUID. The optimization of both tuned and untuned voltmeters and magnetometers is discussed and typical sensitivities are predicted using calculated noise spectra. The calculations are based on an ideal symmetric dc SQUID with % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4baFfea0dXde9vqpa0lb9% cq0dXdb9IqFHe9FjuP0-iq0dXdbba9pe0lb9hs0dXda91qaq-xfr-x% fj-hmeGabaqaciGacaGaaeqabaWaaeaaeaaakeaacqaHYoGycqGH9a% qpcaaIYaacbaGaa8htaiaa-LeadaWgaaWcbaacbiGaa4hmaaqabaGc% caGGVaGaeuOPdy0aaSbaaSqaaiaa+bdaaeqaaOGaeyypa0JaaGymaa% aa!3D23!\[\beta = 2LI_0 /\Phi _0 = 1\] and moderate noise rounding % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4baFfea0dXde9vqpa0lb9% cq0dXdb9IqFHe9FjuP0-iq0dXdbba9pe0lb9hs0dXda91qaq-xfr-x% fj-hmeGabaqaciGacaGaaeqabaWaaeaaeaaakeaaiiGacqWFOaakcq% WFtoWrcqWF9aqpcqWFYaGmcqaHapaCcaWGRbWaaSbaaSqaaiaadkea% aeqaaGqaaOGaa4hvaiaac+cacaGFjbWaaSbaaSqaaerbbjxAHXgaiu% GacaqFWaaabeaakiab-z6agnaaBaaaleaacaqGGaacbiGaaWhmaaqa% baGccqGH9aqpcaaIWaGaaiOlaiaaicdacaaI1aGaaiykaaaa!471A!\[(\Gamma = 2\pi k_B T/I_0 \Phi _{{\rm{ }}0} = 0.05)\], where Φ0 is the flux quantum, T is the temperature, L is the SQUID inductance, and I 0 is the critical current of each junction. The optimum noise temperatures of tuned and untuned voltmeters are found to be 2.8(ΩL/R)T and 8(ΩL/R)T (1 + 1.5α2 + 0.7α4)1/2/α2 respectively, where Ω/2π is the signal frequency, assumed to be much less than the Josephson frequency, and α is the coupling coefficient between the SQUID and its input coil. It is found that tuned and untuned magnetometers can be characterized by optimum effective signal energies given by (16k B TLE/α2 R)[1 + (1 + 1.5α2 + 0.7α2)1/2 + 0.75α2] and 2kB T iRiB/Ω2 L p respectively, where B is the bandwidth, R i is the resistance representing the losses in the tuned circuit at temperature T i and L p is the inductance of the pickup coil.
Electrically stimulated ACTH release in pharmacologically blocked rats.

Plasma levels of corticosterone, obtained prior to and following 15 min sham or electrical stimulation (0.1–0.2mA), were determined fluorometrically for adult female rats which had been pharmacologically blocked with combined dexamethasone (l mg/kg), morphine (20 mg/kg) and pentobarbital (30 mg/kg). Whereas, stimulation of neural sites within the diagonal band of Broca, suprachiasmatic, arcuate, paraventricular and dorsal premammillary nuclei produced significant increases in plasma levels of corticosterone, sham stimulation as well as electrical stimulation of other forebrain areas produced no change in the suppressed levels of plasma corticosterone. These data suggest that the hypothalamic elements immediately involved in the release of ACTH are not distributed diffusely throughout the ventromedial hypothalamus in the usual sense but are localized to discrete hypothalamic sites generally close to the midline. (Endocrinology 93: 835, 1973)
Discriminative stimulus properties of stereoisomers of cyclazocine in phencyclidine-trained squirrel monkeys.

Abstract Squirrel monkeys were trained to discriminate 0.16 mg/kg phencyclidine (PCP) from saline in a two-lever drug discrimination task on a fixed-ratio 32 schedule of food presentation. After reliable discriminative control of lever choice was established, dose-response determinations for generalization to the training dose of PCP were made with several doses of PCP, a racemic mixture of cyclazocine and the pure (+)- and (−)-isomers of cyclazocine. Only PCP and the (+)-isomer produced dose-dependent PCP-appropriate responding. Neither the racemic mixture nor (−)-cyclazocine produced over 25% PCP-appropriate responding at any of the doses tested. (+)-Cyclazocine was eight times less potent than PCP in producing drug-lever appropriate responding. (−)-Cyclazocine was about 30 times more potent than PCP and over 200 times more potent than (+)-cyclazocine in overall response rate suppression. The potency of the racemic mixture for response-rate suppression was consistent with an additive effect of the isomers. Neither the PCP-lever appropriate responding produced by (+)-cyclazocine nor the response-rate suppression produced by (−)-cyclazocine were antagonized by naloxone. Thus, racemic cyclazocine is composed of two isomers with differing behavioral effects. The (−)-isomer is more potent, and the (+)-isomer has more specificity for PCP-like effects.
Adult vasculogenesis occurs through in situ recruitment, proliferation, and tubulization of circulating bone marrow-derived cells

Ischemia is a known stimulus for vascular growth. Bone marrow (BM)-derived endothelial progenitor cells (EPCs) are believed to contribute to new blood vessel growth, but the mechanism for this contribution is unknown. To elucidate how BM cells are able to form new blood vessels, a novel murine model of soft tissue ischemia was developed in lethally irradiated mice with BM reconstituted from either tie2/lacZ or ROSA/green fluorescent protein (GFP) mice (n = 24). BM-derived EPCs were recruited to ischemic tissue within 72 hours, and the extent of recruitment was directly proportional to the degree of tissue ischemia. At 7 days, there were persistently elevated levels of vascular endothelial growth factor (VEGF) (2.5-fold) and circulating VEGF receptor-2/CD11(-) (flk-1(+)/CD11(-)) cells (18-fold) which correlated with increased numbers of BM-derived EPCs within ischemic tissue. The cells were initially located extravascularly as proliferative clusters. By day 14, these clusters coalesced into vascular cords, which became functional vessels by day 21. In vitro examination of human EPCs from healthy volunteers (n = 10) confirmed that EPC proliferation, adhesion, and chemotaxis were all significantly stimulated in hypoxic conditions. We conclude that BM-derived cells produce new blood vessels via localized recruitment, proliferation, and differentiation of circulating cells in a sequence of events markedly different from existing paradigms of angiogenesis.
New analysis of the spectral moments of collision induced absorption in gaseous N2 and CO2

The experimental values of the two lowest spectral moments of the far infrared collision induced absorption spectra of gaseous N2 and CO2 are compared with results from analytical formulas (A. Borysow and M. Moraldi, 1992, Phys. Rev. Lett., 68, 3686) allowing for the anisotropic intermolecular potential. A purely electrostatic induction mechanism was sufficient to reproduce the experimental values of the spectral moments of N2. For CO2, in order to achieve similar agreement, an overlap contribution to the induction terms was introduced. These new terms provide a correction to the present authors' earlier results (M. Gruszka and A. Borysow, 1994, J. chem. Phys., 101, 3573), where no overlap was used. The impact of the anisotropy of the intermolecular potential on the spectral moments of N2 and CO2 has been analysed, and also the applicability of perturbation theory for computing the spectral moments. In both cases, N2 and CO2, it was found that the perturbation series does not converge, when realistic inte...
A Core Folding Model for Catalysis by the Hammerhead Ribozyme Accounts for Its Extraordinary Sensitivity to Abasic Mutations

Introducing abasic nucleotides at each of 13 positions in the conserved core of the hammerhead ribozyme causes a large decrease in the extent of catalysis (Peracchi, A., et al. (1996) Proc. Natl. Acad. Sci. U.S.A. 93, 11522). This extreme sensitivity to structural defects is in contrast to the behavior of protein enzymes and larger ribozymes. Several additional differences in the behavior of the hammerhead relative to that of protein enzymes and larger ribozymes are described herein. The deleterious effects of the abasic mutations are not relieved by lowering the temperature, by increasing the concentration of monovalent or divalent metal ions, or by adding polyamines, in contrast to effects observed with protein enzymes and large RNA enzymes. In addition, the abasic mutations do not significantly weaken substrate binding. These results and previous observations are all accounted for by a "core folding" model in which the stable ground state structure of the hammerhead ribozyme complexed with the substrate is a partially folded state that must undergo an additional folding event to achieve its catalytic conformation. We propose that the peculiar behavior of the hammerhead arises because the limited structural interconnections in a small RNA enzyme do not allow the ground state to stably adopt the catalytic conformation; within the globally folded catalytic conformation, limited structural interconnections may further impair catalysis by hampering the precise alignment of active site functional groups. This behavior represents a basic manifestation of the well-recognized interconnection between folding and catalysis.
The Effects of Aggression Replacement Training on Antisocial Behavior in a Runaway Shelter

Afield study was conducted to investigate the effects of Aggression Replacement Training (ART) on the antisocial behavior of adolescents in a runaway shelter. An interrupted time series design was ...
Highly enantioselective synthesis of γ-, δ-, and ε-chiral 1-alkanols via Zr-catalyzed asymmetric carboalumination of alkenes (ZACA)-Cu- or Pd-catalyzed cross-coupling.

Despite recent advances of asymmetric synthesis, the preparation of enantiomerically pure (≥99% ee) compounds remains a challenge in modern organic chemistry. We report here a strategy for a highly enantioselective (≥99% ee) and catalytic synthesis of various γ- and more-remotely chiral alcohols from terminal alkenes via Zr-catalyzed asymmetric carboalumination of alkenes (ZACA reaction)–Cu- or Pd-catalyzed cross-coupling. ZACA–in situ oxidation of tert-butyldimethylsilyl (TBS)-protected ω-alkene-1-ols produced both (R)- and (S)-α,ω-dioxyfunctional intermediates (3) in 80–88% ee, which were readily purified to the ≥99% ee level by lipase-catalyzed acetylation through exploitation of their high selectivity factors. These α,ω-dioxyfunctional intermediates serve as versatile synthons for the construction of various chiral compounds. Their subsequent Cu-catalyzed cross-coupling with various alkyl (primary, secondary, tertiary, cyclic) Grignard reagents and Pd-catalyzed cross-coupling with aryl and alkenyl halides proceeded smoothly with essentially complete retention of stereochemical configuration to produce a wide variety of γ-, δ-, and e-chiral 1-alkanols of ≥99% ee. The MαNP ester analysis has been applied to the determination of the enantiomeric purities of δ- and e-chiral primary alkanols, which sheds light on the relatively undeveloped area of determination of enantiomeric purity and/or absolute configuration of remotely chiral primary alcohols.
Finite-Amplitude Wave Activity and Mean Flow Adjustments in the Atmospheric General Circulation. Part I: Quasigeostrophic Theory and Analysis

Abstract A diagnostic relationship between finite-amplitude wave activity and the associated adiabatic adjustments to the zonal-mean zonal wind and temperature is developed in the quasigeostrophic (QG) framework and is applied to a 23-yr segment (1979–2001) of the 40-yr ECMWF Re-Analysis (ERA-40) data. Wave activity is defined in terms of an instantaneous areal displacement of QG potential vorticity (PV) from zonal symmetry. Unlike previous forms, the tendency of wave activity equals exactly the negative of the eddy PV flux (Eliassen–Palm flux divergence) in the conservative limit, even at finite amplitude. This allows one to integrate the transformed Eulerian mean (TEM) theory in time and quantify the departure (adiabatic adjustment) of the zonal-mean state from an eddy-free reference state in terms of the observed wave activity. The structure of wave activity identifies synoptic eddies in the extratropics and planetary waves in the high latitudes of winter-to-spring stratosphere. In addition, a thin lay...
Retrospective correction of surface coil MR images using an automatic segmentation and modeling approach

The use of surface coils in magnetic resonance imaging offers significant improvements in the signal-to-noise ratio over volume coils for many applications. However, the inhomogeneous reception profile of surface coils hampers their usefulness by introducing significant nonuniformities or intensity variations which can vary by greater than six-fold across the sample. In this study, we evaluated an automatic technique for retrospective correction of intensity variations observed in a high-resolution surface coil MR image of the rat brain obtained using an adiabatic magnetic resonance imaging sequence. The images are shown to have a coefficient of variation less than 12% following application of this correction algorithm. This image intensity correction technique can be applied retrospectively to all data sets and corrects both sample/patient dependent effects (e.g. attenuation of overlying tissue) or sample independent effects (e.g. coil geometry or position). This approach should also prove valuable in improving regions of interest analysis, volume histograms and thresholding techniques.
Interpretation of the international normalised ratio in patients with liver disease

Wide acceptance of the international normalised ratio (INR) and thromboplastins with low international sensitivity indices (ISIs) has inadvertently led to the application of the INR to patients other than those on anticoagulation treatment. I examined the degree of factor deficiency for a given INR in patients with liver disease and controls receiving stable-dose warfarin. The degree of factor V and VII, but not prothrombin, deficiencies for a given INR were greater in liver patients than controls. The INR measured with a low-ISI thromboplastin can quantify the coagulation status of patients with liver disease, but should not be interpreted as having the same meaning as the INR in patients receiving warfarin.
Development and fecundity rate of Tribolium castaneum (Herbst) on Distillers Dried Grains with Solubles

Abstract This research focused on the influence of two samples of corn Distillers Dried Grains with Solubles (DDGS) obtained from an “old” generation dry-grind fuel ethanol plant as a food and oviposition resource for red flour beetle, Tribolium castaneum, in contrast with traditional flour (90%)/yeast (10%) diet. Larval development was significantly faster on a flour/yeast diet (18.6 d) compared to the DDGS sample 1 (44.1 d) and DDGS sample 2 (34.5 d). DDGS sample 1 had the highest larval mortality (38.7%) with a wider mortality range (6.7–66.7%) compared with flour/yeast (4.4%, range 0–14.3%) and DDGS sample 2 (7.1, range 0–26.7%). Both DDGS diets and the flour/yeast diet had no significant influence on egg incubation period or pupation time and percentage of egg hatching or pupal mortality. Additionally, fecundity was significantly lower on DDGS compared to the flour/yeast diet (18.0, 36.5, and 175.5 eggs per female on DDGS sample 1, DDGS sample 2, and flour/yeast diet, respectively). These results indicate that this type of DDGS is not a suitable developmental diet compared to the standard laboratory diet and that the addition of this type of DDGS to animal feeds should not increase feed vulnerability to flour beetle infestation. A comparison of DDGS samples by particle size indicated that the larger particle size, sample 1 was less suitable for T. castaneum oviposition and development.
MAKING EVIDENCE-BASED DECISIONS IN MEDICINE: (OR MORE IMPORTANTLY) USING EVIDENCE WHEN THE CASE DOESN'T QUITE FIT

e p 1 b m n T m d v c i w v n trying to establish evidence of an impact on health utcomes associated with a new treatment, a randomzed clinical trial (RCT) is undisputedly called the gold tandard—the best evidence you can get from a single tudy. Better yet, a structured meta-analysis of the vidence from several RCTs evaluating the same therpy, such as those conducted under the aegis of the ochrane groups, (cf The Cochrane Collaboration, 003; O’Connor et al., 1999b; O’Connor et al., 2001; lsen et al., 1998) provide the most widely respected cientific basis for estimating the likelihood of achievng any impact on health outcomes (its potential to mprove health or at least avoid the untoward conseuences of untreated disease) as well as estimating armful side effects of the treatment (its potential to arm). There are some standards to assess the helpfulness nd harmfulness of a therapy that take into account he seriousness of the harms and benefits from the reatment as well as their likelihood, and compare it to lternative treatment choices—including no treatent. For example, the Federal Drug Agency has everal explicit standards it uses to evaluate new rugs or to change the status of a drug’s availability rom prescription to over the counter. Various expert anels, such as the Task Force on Preventive Mediine, professional organizations, and consensus roups also attempt to set criteria to help weigh the vidence to arrive at a recommended therapy or
Computed tomography of retroperitoneal fluid collections

F LUID collections in the retroperitoneum generally consist of pus, hemorrhage, or urine. Infections in this area are typically subacute with nonspecific symptoms of chills, fever, night sweats, and pain. The retroperitoneum has been difficult to evaluate clinically; the diagnosis of retroperitoneal abscess or inflammation has been overlooked in 25-50s of patients.‘,’ Unfortunately, the morbidity and mortality increase with delayed diagnosis; failure to drain an abscess results in a mortality that approaches I OO%.’ For similar reasons, retroperitoneal hemorrhage and urinoma have been difficult to diagnose. With the advent of CT, however, the retroperitoneum can now be well demonstrated in most people. The normal bilateral symmetry, the usual abundance of fat, and the lack of motion in this region are ideal for CT examination.
Surface plasmon beats formed on thin metal films

Surface plasmon polaritons, sometimes referred to as Surface Plasmons (SPs) have brought us great opportunities to work in nanoscale at optical frequencies. The SPs at the two surfaces of a thin metal film interact with each other, hence generate new modes which are either symmetric or anti-symmetric. For anti-symmetric modes, the dispersion curve turns to be of negative slope at large wave vectors, so two different anti-symmetric modes can be excited at the same frequency. These two modes can form beats with novel features. The envelope (profile) of the beating SP waves could be stationary, which means its shape will not change in time. Our simulation results clearly showed such phenomena, which is a strong evidence of the SPs dispersion relations at the thin metal film. It is a proof of the existence of negative group velocity of SPs. Beats can help us determine the difference in k and the amplitudes ratio of the two beating waves. We also studied beating between anti-symmetric mode and symmetric mode SPs with the same frequency. The study of the energy density distribution showed that the output from such system can be well controlled through beats formation. Example by using NSOM (Near-field Scanning Optical Microscopy) has been simulated. The beating phenomena have a potential application in the integrated optical circuits.
Current-Voltage Characteristics of Self-Assembled Monolayers by Scanning Tunneling Microscopy

This paper presents a comparison of the theoretical and experimental current-voltage (I-V) characteristics of a self-assembled monolayer of $\ensuremath{\alpha},{\ensuremath{\alpha}}^{\ensuremath{'}}\ensuremath{-}\mathrm{x}\mathrm{y}\mathrm{l}\mathrm{y}\mathrm{l}$ dithiol molecules on a gold substrate measured with a scanning tunneling microscope probe. Good quantitative agreement is obtained with the tip-molecule distance as the only ``fitting parameter.'' Several other thiol-coupled molecules that we have studied also show similar agreement. The conceptual picture presented in this paper could be useful for the interpretation of I-V measurements on molecular monolayers in general.
Neutrophil adhesion molecule expression during cardiopulmonary bypass with bubble and membrane oxygenators

Abstract The neutrophil-mediated tissue injury associated with cardiopulmonary bypass (CPB) is thought to require the interaction of specific neutrophil and endothelial adhesion molecules. In this study, the effects of CPB on the expression of neutrophil CD11b and CD18 (the components of the Mac-1 adhesion molecule) were examined; the effects of membrane versus bubble oxygenators on the expression of neutrophil CD11b and CD18 were compared; and the plasma levels of the intercellular adhesion molecule-1 (cICAM-1), an inducible endothelial adhesion molecule, were measured. In addition, the time courses of complement activation and neutrophil granule release were measured to determine their temporal relationship to the expression of the neutrophil adhesion molecule. Fifteen adult patients underwent procedures requiring cardiopulmonary bypass; hollow-fiber membrane oxygenators were used in 8 (group M) and bubble oxygenators were used in 7 (group B). Blood samples were drawn before, during, and after CPB for determination of the expression of neutrophil CD11b and CD18 (immunofluorescent flow cytometry), and the plasma cICAM-1, elastase, lactoferrin (enzyme-linked immunoabsorbent assay), and plasma C3a (radioimmunoassay) levels. CPB caused an immediate and sustained increase in the neutrophil CD11b and CD18 expression in both groups; after 60 minutes of CPB, CD11b expression had increased by 116.9% ± 19.1% in group B and by 79.3% ± 8.5% in group M ( p = 0.78). Over the same period, CD18 expression increased by 97.2% ± 17.9% in group B and by 72.4% ± 16.8% in group M ( p = 0.67). Increased neutrophil adhesion molecule expression was accompanied by elevations in the plasma elastase, lactoferrin, and C3a levels; there were no differences between oxygenator groups for any of these parameters. Before CPB, the plasma cICAM-1 levels were similar in the two groups (group B, 175.6 ± 25.6 ng/ml; group M, 200.2 ± 30 ng/ml). Twenty-four hours after CPB, the plasma cICAM-1 level increased to 289.1 ± 31.1 ng/ml in group B patients ( p
Distributed Kalman filtering based on quantized innovations

We consider state estimation of a Markov stochastic process using an ad hoc wireless sensor network (WSN) based on noisy linear observations. Due to power and bandwidth constraints present in resource- limited WSNs, the observations are quantized before transmission. We derive a distributed recursive mean-square error (MSE) optimal quantizer-estimator based on the quantized observations. The resultant Kalman-like algorithm based on quantized observations exhibits MSE performance and computational complexity comparable to the Kalman filter based on un-quantized observations even for 2-3 bits of quantization per observation.
Effects of oxygen on engineered cardiac muscle.

Concentration gradients associated with the in vitro cultivation of engineered tissues that are vascularized in vivo result in the formation of only a thin peripheral tissue-like region (e.g., ∼100 μm for engineered cardiac muscle) around a relatively cell-free interior. We previously demonstrated that diffusional gradients within engineered cardiac constructs can be minimized by direct perfusion of culture medium through the construct. In the present study, we measured the effects of medium perfusion rate and local oxygen concentration (p) on the in vitro reconstruction of engineered cardiac muscle. Neonatal rat cardiomyocytes were seeded onto biodegradable polymer scaffolds (fibrous discs, 1.1 cm diameter × 2 mm thick, made of polyglycolic acid, 24 × 106 cells per scaffold). The resulting cell-polymer constructs were cultured for a total of 12 days in serially connected cartridges (n = 1–8), each containing one construct directly perfused with culture medium at a flow rate of 0.2–3.0 mL/min. In all groups, oxygen concentration decreased due to cell respiration, and depended on construct position in the series and medium flow rate. Higher perfusion rates and higher p correlated with more aerobic cell metabolism, and higher DNA and protein contents. Constructs cultured at p of 160 mm Hg had 50% higher DNA and protein contents, markedly higher expression of sarcomeric α-actin, better organized sarcomeres and cell junctions, and 4.5-fold higher rate of cell respiration as compared to constructs cultured at p of 60 mm Hg. Contraction rates of the corresponding cardiac cell monolayers were 40% higher at p of 160 than 60 mm Hg. The control of oxygen concentration in cell microenvironment can thus improve the structure and function of engineered cardiac muscle. Experiments of this kind can form a basis for controlled studies of the effects of oxygen on the in vitro development of engineered tissues. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 617–625, 2002.
Multihop Relaying for Broadband Wireless Mesh Networks: From Theory to Practice

We summarize capacity results to show merits of multihop relaying in broadband cellular mesh networks. Under the guidance of these results, we provide design perspectives on relay deployment, spectrum allocation, and end-to-end optimization of certain QoS measures such as throughput, coverage, reliability, and robustness. We conclude with an overview of recent standardization activities and remarks on remaining open problems and design challenges.
Ecosystem carbon storage capacity as affected by disturbance regimes: A general theoretical model

Disturbances have been recognized as a key factor shaping terrestrial ecosystem states and dynamics. A general model that quantitatively describes the relationship between carbon storage and disturbance regime is critical for better understanding large scale terrestrial ecosystem carbon dynamics. We developed a model (REGIME) to quantify ecosystem carbon storage capacities (E[x]) under varying disturbance regimes with an analytical solution E[x] = U {center_dot} {tau}{sub E} {center_dot} {lambda}{lambda} + s {tau} 1, where U is ecosystem carbon influx, {tau}{sub E} is ecosystem carbon residence time, and {tau}{sub 1} is the residence time of the carbon pool affected by disturbances (biomass pool in this study). The disturbance regime is characterized by the mean disturbance interval ({lambda}) and the mean disturbance severity (s). It is a Michaelis-Menten-type equation illustrating the saturation of carbon content with mean disturbance interval. This model analytically integrates the deterministic ecosystem carbon processes with stochastic disturbance events to reveal a general pattern of terrestrial carbon dynamics at large scales. The model allows us to get a sense of the sensitivity of ecosystems to future environmental changes just by a few calculations. According to the REGIME model, for example, approximately 1.8 Pg C will be lost in the high-latitude regionsmore » of North America (>45{sup o} N) if fire disturbance intensity increases around 5.7 time the current intensity to the end of the twenty-first century, which will require around 12% increases in net primary productivity (NPP) to maintain stable carbon stocks. If the residence time decreased 10% at the same time additional 12.5% increases in NPP are required to keep current C stocks. The REGIME model also lays the foundation for analytically modeling the interactions between deterministic biogeochemical processes and stochastic disturbance events.« less
Tools to aid post-wildfire assessment and erosion-mitigation treatment decisions

A considerable investment in post-fire research over the past decade has improved our understanding of wildfire effects on soil, hydrology,erosion and erosion-mitigationtreatment effectiveness. Using thisnew knowledge, we have developed several tools to assist land managers with post-wildfire assessment and treatment decisions, such as prediction models, research syntheses, equipment and methods for field measurements, reference catalogues and databases of past-practice, and spreadsheets for calculating resource valuation and cost-benefit analysis. These tools provide relevantscience topost-fireassessment teams andlandmanagers informats that often canbe directly enteredinto assessment and treatment decision-making protocols. Providing public access to these tools through the internet not only has increased their dissemination, but also has allowed them to be updated and improved as new knowledge and technology become available. The use of these science-based tools has facilitated a broader application of current knowledge to post-fire management in the United States and in other fire-prone areas around the world. Additional keywords: burn severity, erosion modeling, remote sensing, resource valuation.
Witchcraft Prosecutions and the Decline of Magic

Witchcraft prosecutions in Europe rose dramatically during the late sixteenth century, peaked in the middle third of the seventeenth century, and declined rapidly thereafter, gradually ceasing altogether by the end of the eighteenth century. The rise was driven by the dissemination of the late-medieval demonology and the “scissors effect” of rising population and constricting resources; the peak reflected the governing elite's “crisis of confidence” in the prosecutions and the demonology. The trials ended because the elite's skepticism about the magnitude of the threat posed by witchcraft gave way to disbelief in the power of magic altogether. The “crisis of confidence” manifested not only the victory of a long-standing tradition of skepticism and contemporary experience with the cruelty and injustices of the trials but also changes in popular behaviors and practices that the trials brought about. The growing acceptance of the new mechanical philosophy was less a cause than a consequence of the decline of...