Extracting sentiment from text is a hard semantic problem. We develop a methodology for extracting small investor sentiment from stock message boards. The algorithm comprises different classifier ...algorithms coupled together by a voting scheme. Accuracy levels are similar to widely used Bayes classifiers, but false positives are lower and sentiment accuracy higher. Time series and cross-sectional aggregation of message information improves the quality of the resultant sentiment index, particularly in the presence of slang and ambiguity. Empirical applications evidence a relationship with stock values—tech-sector postings are related to stock index levels, and to volumes and volatility. The algorithms may be used to assess the impact on investor opinion of management announcements, press releases, third-party news, and regulatory changes.
Austenite stability is essentially important in improving the cryogenic toughness of cryogenic Ni steels and guiding the development of Ni-saving cryogenic steels. The austenite stability in the ...cryogenic Ni steels is influenced by many microstructure features, making it a complicated issue which is lack of a systematic discussion. In this article, the microstructural effects on the thermal and mechanical stability of austenite in the cryogenic Ni steels are reviewed and discussed. The thermal stability of austenite (TSA) will be enhanced by the enrichment of austenite-stabilizing elements in the austenite which decreases the martensite-start (
M
s
) temperature. The grain refinement enhances the TSA by synergistically increasing the nonchemical driving force for the martensite transformation and the concentrations of austenite-stabilizing elements in the austenite. The excessive increase in the volume fraction of austenite weakens the TSA by decreasing the concentrations of austenite-stabilizing elements in the austenite. The film austenite is usually thermally more stable than the block austenite owing to its higher concentrations of austenite-stabilizing elements. The mechanical stability of austenite (MSA) is also influenced by the concentrations of austenite-stabilizing elements which affect the
M
s
temperature. The reports on the effect of grain size of austenite on the MSA are inconsistent. Both negligible and important effects of the grain size of austenite on the MSA are analyzed. The grain orientation of austenite affects the MSA via changing the Schmid factor and the additional driving force for the martensite transformation. The orientation which yields a larger value of Schmid factor would exhibit a lower MSA. The MSA is affected by the matrix or the neighboring phase due to the stress and strain partitioning among austenite and other constituent phases. The dislocation multiplication could weaken the MSA by assisting the nucleation and growth of martensite embryo and enhance the MSA by hindering the motion of embryo/austenite interfaces when dislocation density is sufficiently large. Austenite with a combination of a high TSA and a moderate or high MSA is considered to be effective strategies to enhance cryogenic toughness of the cryogenic Ni steels.
Tolerance to the analgesic effect of opioids complicates the management of persistent pain states. We tested whether the intrathecal infusion of small interfering RNA (siRNA) against β-arrestin 2 ...would reduce tolerance to chronic morphine use and the severity of precipitated morphine withdrawal.
Intrathecal β-arrestin 2 (2 μg siRNA per 10 μl per rat) was injected once daily for 3 days. Rats then received a continuous intrathecal infusion of morphine (2 nmol h−1) or saline for 7 days. Daily tail-flick (TF) and intrathecal morphine challenge tests were performed to assess the effect of intrathecal β-arrestin 2 siRNA on antinociception and tolerance to morphine. Naloxone withdrawal (2 mg kg−1) was performed to assess morphine dependence.
In the daily TF test, the antinociception of intrathecal morphine was increased and maintained in rats receiving β-arrestin 2 siRNA compared with the control group (morphine alone). In the probe response test, rats receiving morphine infusion with β-arrestin 2 siRNA treatment showed a significant left shift in their dose–response curve, as measured by per cent maximal possible effect (MPE), such that the AD50 was significantly decreased by a factor of 5.6 when compared with that of morphine-infused rats. In the naloxone-induced withdrawal tests, rats receiving β-arrestin 2 siRNA injection with morphine infusion showed a significant reduction in four of the six signs of withdrawal.
We show here that intrathecal β-arrestin 2 siRNA in rats enhances analgesia and attenuates naloxone-induced withdrawal symptoms. This may warrant further investigation in the context of long-term use of intrathecal opioids for controlling chronic pain.
Head and neck malignancies comprise a heterogeneous group of malignancies that cause significant morbidity to those affected. These malignancies are associated with specific risk factors and ...exposures, some of which impact prognosis. The most common risk factors for developing head and neck cancers are tobacco and alcohol use. Marijuana and e-cigarettes, occupational exposures, and use of topical substances have also been linked to head and neck cancers. Human papilloma virus has been associated with oropharyngeal cancer. Such measures as oral hygiene, screening, smoking cessation, and vaccination are measures taken to decrease the incidence and morbidity of head and neck cancers.
Estimating epidemiological cutoff endpoints (ECVs/ECOFFS) may be hindered by the overlap of MICs for mutant and nonmutant strains (strains harboring or not harboring mutations, respectively). ...Posaconazole MIC distributions for the
species complex were collected from 26 laboratories (in Australia, Canada, Europe, India, South and North America, and Taiwan) and published studies. Distributions that fulfilled CLSI criteria were pooled and ECVs were estimated. The sensitivity of three ECV analytical techniques (the ECOFFinder, normalized resistance interpretation NRI, derivatization methods) to the inclusion of MICs for mutants was examined for three susceptibility testing methods (the CLSI, EUCAST, and Etest methods). The totals of posaconazole MICs for nonmutant isolates (isolates with no known
mutations) and mutant
isolates were as follows: by the CLSI method, 2,223 and 274, respectively; by the EUCAST method, 556 and 52, respectively; and by Etest, 1,365 and 29, respectively. MICs for 381 isolates with unknown mutational status were also evaluated with the Sensititre YeastOne system (SYO). We observed an overlap in posaconazole MICs among nonmutants and
mutants. At the commonly chosen percentage of the modeled wild-type population (97.5%), almost all ECVs remained the same when the MICs for nonmutant and mutant distributions were merged: ECOFFinder ECVs, 0.5 μg/ml for the CLSI method and 0.25 μg/ml for the EUCAST method and Etest; NRI ECVs, 0.5 μg/ml for all three methods. However, the ECOFFinder ECV for 95% of the nonmutant population by the CLSI method was 0.25 μg/ml. The tentative ECOFFinder ECV with SYO was 0.06 μg/ml (data from 3/8 laboratories). Derivatization ECVs with or without mutant inclusion were either 0.25 μg/ml (CLSI, EUCAST, Etest) or 0.06 μg/ml (SYO). It appears that ECV analytical techniques may not be vulnerable to overlap between presumptive wild-type isolates and
mutants when up to 11.6% of the estimated wild-type population includes mutants.
In this paper, an elastic metamaterial with multiple dissipative resonators is presented for broadband wave mitigation by properly utilizing interactions from resonant motions and viscoelastic ...effects of the constitutive material. The working mechanism of the metamaterial to suppress broadband waves is clearly revealed in a dissipative mass-in-mass lattice system through both negative effective mass density and effective metadamping coefficient. Based on the novel metadamping mechanism, a microstructure design of the dissipative metamaterial made of multi-layered viscoelastic continuum media is first proposed for efficient attenuation of a transient blast wave. It is found that the extremely broadband waves can be almost completely mitigated with metamaterials at subwavelength scale. The results of the study could be used in developing new multifunctional composite materials to suppress the shock or blast waves which may cause severe local damage to engineering structures.
How early-life colonization and subsequent exposure to the microbiota affect long-term tissue immunity remains poorly understood. Here, we show that the development of mucosal-associated invariant T ...(MAIT) cells relies on a specific temporal window, after which MAIT cell development is permanently impaired. This imprinting depends on early-life exposure to defined microbes that synthesize riboflavin-derived antigens. In adults, cutaneous MAIT cells are a dominant population of interleukin-17A (IL-17A)-producing lymphocytes, which display a distinct transcriptional signature and can subsequently respond to skin commensals in an IL-1-, IL-18-, and antigen-dependent manner. Consequently, local activation of cutaneous MAIT cells promotes wound healing. Together, our work uncovers a privileged interaction between defined members of the microbiota and MAIT cells, which sequentially controls both tissue-imprinting and subsequent responses to injury.
Abstract
As a quantum material, Weyl semimetal has a series of electronic-band-structure features, including Weyl points with left and right chirality and corresponding Berry curvature, which have ...been observed in experiments. These band-structure features also lead to some unique nonlinear properties, especially high-order harmonic generation (HHG) due to the dynamic process of electrons under strong laser excitation, which has remained unexplored previously. Herein, we obtain effective HHG in type-II Weyl semimetal β-WP
2
crystals, where both odd and even orders are observed, with spectra extending into the vacuum ultraviolet region (190 nm, 10th order), even under fairly low femtosecond laser intensity. In-depth studies have interpreted that odd-order harmonics come from the Bloch electron oscillation, while even orders are attributed to Bloch oscillations under the “spike-like” Berry curvature at Weyl points. With crystallographic orientation-dependent HHG spectra, we further quantitatively retrieved the electronic band structure and Berry curvature of β-WP
2
. These findings may open the door for exploiting metallic/semimetallic states as solid platforms for deep ultraviolet radiation and offer an all-optical and pragmatic solution to characterize the complicated multiband electronic structure and Berry curvature of quantum topological materials.
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