gebhart/patrepeval huggingface dataset:
4.4 - Tiny Mid- and Long-Wave Infrared Spectrometer Mo¬dule with a MEMS Dual-Band Fabry-Pérot Filter (2011)

Cost effective and highly miniaturized spectrometer modules for infrared absorption spectroscopy in the mid wave infrared (MWIR) based on the hybrid integration of pyroelectric detectors and MEMS Fabry-Pérot filters (FPF) have been developed and are commercially available. The filters, based on bulk micromachining and Si-SiO2 Bragg reflectors exhibit a high finesse up to 60 over the entire aperture of Ø 1.9 mm. However, many substances have strong and more specifiable absorption bands in the long wave infrared (LWIR) from 8 to 12 ?m (fingerprint region). This paper reports on new Dual-Band FP-Filters, which can be operated simultaneously in the mid and long wave infrared by using the first and second interference order. For the LWIR new materials have to be chosen to create the reflectors. Using three material components instead of two gives additional degrees of freedom to optimize reflectance and phase dispersion and - most important - to achieve stress compensation within the dielectric layer stack. A conventional Bragg reflector consisting of high (H) and low (L) refracting quarter-wave stacks cannot cover the whole range of 3 - 12 µm. The new design approach with a |HLH| base period offers two stop bands within the desired regions. First samples of Dual-Band reflectors, optimized for 4 - 4.8 µm and 8 - 10.5 µm, have been fabricated and tested in tunable FP-Filters. The reflectors exhibit a very low curvature of <= 10 nm. A revised chip layout was made completely symmetrical, which significantly reduces reflector tilting and gives rise to a remarkable high defect finesse. Spectral measurements show a high peak transmittance of about 80 % in both ranges and low bandwidths of < 120 nm in the long wave band and < 60 nm in the short wave band. This corresponds to an effective finesse of about 56. Further optimized designs are under development to improve the finesse combined with a wider tuning range. The spectrometer module is based on a dual channel pyroelectric detector, one channel for each band. The spectral separation of the two bands is realized by means of a dichroic beamsplitter and two broad bandpass filters. Compared to conventional 50:50 beamsplitters this solution minimizes signal losses in the optical path. The complete spectrometer module fits in a TO-8 package. First prototypes were fabricated and tested.
Vacuolar Localization of Ethylene-Induced Chitinase in Bean Leaves (1984)

The localization of ethylene-induced endochitinase was studied in bean (Phaseolus vulgaris L. cv Saxa) leaves. The specific activity of chitinase in mesophyll protoplasts isolated from the leaves was as high as in tissue homogenates, indicating that most of the enzyme was located intracellularly. Vacuoles isolated and purified from the protoplasts were found to contain most of the intracellular chitinase activity.
Noninterfacial-nitride formation ohmic contact mechanism in Si-containing Ti∕Al∕Mo∕Au metallizations on AlGaN∕GaN heterostructures (2005)

Excellent ohmic contact formation to undoped-AlGaN∕GaN heterostructures is achieved by the incorporation of silicon into Ti∕Al∕Mo∕Au metallization. Contact resistance and specific contact resistivity as low as 0.16Ωmm and 6.77×10−7Ωcm2, respectively, have been obtained for the Ti∕Si∕Al∕Si∕Mo∕Au scheme. Transmission electron microscopy has revealed that the ohmic contact formation mechanism depends on the competing interfacial nitride and silicide formation reactions, the latter giving rise to improved contact performance. The formation and penetration of non-nitride reaction products of Si-containing Al–Au intermetallics to depths beyond the AlGaN∕GaN interface were observed. The superior ohmic performance of these schemes suggests that silicide-based low Schottky barrier contact formation may be preferable to an interfacial nitride contact mechanism in achieving improved ohmic behavior.
Myeloid-derived suppressor cells express the death receptor Fas and apoptose in response to T cell–expressed FasL (2011)

Myeloid-derived suppressor cells (MDSCs) inhibit adaptive and innate immunity and accumulate in the blood of persons with cancer, chronic inflammation, trauma, infection, and stress. Some of the factors inducing their accumulation are known; however, mechanisms regulating their turnover have not been identified. Mass spectrometry showed prominent expression of apoptosis pathway proteins, suggesting that MDSC turnover may be regulated by Fas-FasL-mediated apoptosis. This hypothesis was confirmed by showing that blood MDSCs induced by 3 mouse tumors were Fas(+) and apoptosed in response to Fas agonist in vitro and to activated FasL(+) T cells in vivo. FasL-deficient mice contained significantly more blood MDSCs than FasL(+/+) mice, and after removal of primary tumors MDSCs regressed in STAT6(-/-) and CD1(-/-) mice but not in STAT6(-/-)FasL(-/-) or CD1(-/-)FasL(-/-) mice. Fas(+) macrophages and dendritic cells did not apoptose in response to activated T cells, indicating that Fas-FasL regulation of myeloid cells was restricted to MDSCs. These results identify a new mechanism regulating MDSC levels in vivo and show a retaliatory relationship between T cells and MDSCs in that MDSCs suppress T-cell activation; however, once activated, T cells mediate MDSC apoptosis.
Transgenic Overexpression of β2-Adrenergic Receptors in Airway Smooth Muscle Alters Myocyte Function and Ablates Bronchial Hyperreactivity (1999)

beta(2)-Adrenergic receptors (beta(2)AR) act to relax airway smooth muscle and can serve to counteract hyperresponsiveness, although the effect may not be ablative even in the presence of exogenous agonist. Within this signaling cascade that ultimately transduces smooth muscle relaxation, a significant "spare receptor" pool has been hypothesized to be present in the airway. In order to modify the relationship between beta(2)AR and downstream effectors, transgenic mice (TG) were created overexpressing beta(2)AR approximately 75-fold in airway smooth muscle using a mouse smooth muscle alpha-actin promoter. While >90% of these receptors were expressed on the smooth muscle cell surface, the percentage of receptors able to form the agonist-promoted high affinity complex was less than that found with nontransgenic (NTG) cells (R(H) = 18 versus 36%). Nevertheless, beta(2)AR signaling was found to be enhanced. Intact airway smooth muscle cells from TG had basal cAMP levels that were greater than NTG cells. A marked increase in agonist-stimulated cAMP levels was found in the TG ( approximately 200% stimulation over basal) compared with NTG ( approximately 50% over basal) cells. Adenylyl cyclase studies gave similar results and also showed a 10-fold lower EC(50) for TG cells. Tracheal rings from TG mice that were precontracted with acetylcholine had an enhanced responsiveness (relaxation) to beta-agonist, with a 60-fold decrease in the ED(50), indicating that the enhanced signaling imposed by overexpression results in an increase in the coordinated function of the intact airway cells. In vivo studies showed a significantly blunted airway resistance response to the inhaled bronchoconstrictor methacholine in the TG mice. Indeed, with beta-agonist pretreatment, the TG mice displayed no response whatsoever to methacholine. These results are consistent with beta(2)AR being the limiting factor in the transduction system. Increases in the initial component of this transduction system (the beta(2)AR) are sufficient to markedly alter signaling and airway smooth muscle function to the extent that bronchial hyperresponsiveness is ablated, consistent with an anti-asthma phenotype.
Effect of Biofilm on the Mechanical Properties and Repair Strength of Denture Acrylic (2014)

Hypothesis: The null hypothesis was that presence and exposure to biofilm from C. albicans would have no effect on the mechanical properties and repair strength of denture acrylics. Objective: To test whether exposure to C. albicans and subsequent biofilm formation would have an effect on the mechanical properties and repair strength of denture acrylic. Methods: 90 samples of Lucitone 199® denture acrylic were fabricated from a standardized jig and processed with conventional flask and process methods. Samples were randomly assigned to 3 groups: control, 3 days (3d), and 12 days (12d) for subsequent C. albicans exposure. Initial and post treatment measurements were taken for microhardness, surface roughness, and flexural strength on repaired and unrepaired samples. Results: Statistically significant differences were observed between control and experimental samples in repair flexural strength and microhardness (p< 0.05). Differences were also observed in surface roughness, but not statistically significant (p> 0.05). Cohesive failures increased as exposure time increased. Conclusions: The null hypothesis was rejected as exposure to C. albicans had a significant effect on the microhardness and repair flexural strength of denture acrylic. Changes in mode of failure and surface roughness were observed, indicating a possible change in surface topography with biofilm formation. These changes are further information the clinician can use in deciding if repair or replacement of a fractured acrylic prosthesis is warranted.
Staggered-lineup heterojunctions as sources of tunable below-gap radiation: Operating principle and semiconductor selection (1983)

Heterojunctions in which both the conduction and the valence band edges of one semiconductor are shifted upward relative to those of the other, can exhibit adjacent dual quantum wells for electrons and holes on the two sides of the interface. Tunneling-assisted radiative recombination between the wells should be an efficient, bias-tunable source of radiation at below-gap quantum energies. Several semiconductor combinations that exhibit the proper lineup are available.
An Autoregressive Model-Based Particle Filtering Algorithms for Extraction of Respiratory Rates as High as 90 Breaths Per Minute From Pulse Oximeter (2010)

We present particle filtering (PF) algorithms for an accurate respiratory rate extraction from pulse oximeter recordings over a broad range: 12-90 breaths/min. These methods are based on an autoregressive (AR) model, where the aim is to find the pole angle with the highest magnitude as it corresponds to the respiratory rate. However, when SNR is low, the pole angle with the highest magnitude may not always lead to accurate estimation of the respiratory rate. To circumvent this limitation, we propose a probabilistic approach, using a sequential Monte Carlo method, named PF, which is combined with the optimal parameter search (OPS) criterion for an accurate AR model-based respiratory rate extraction. The PF technique has been widely adopted in many tracking applications, especially for nonlinear and/or non-Gaussian problems. We examine the performances of five different likelihood functions of the PF algorithm: the strongest neighbor, nearest neighbor (NN), weighted nearest neighbor (WNN), probability data association (PDA), and weighted probability data association (WPDA). The performance of these five combined OPS-PF algorithms was measured against a solely OPS-based AR algorithm for respiratory rate extraction from pulse oximeter recordings. The pulse oximeter data were collected from 33 healthy subjects with breathing rates ranging from 12 to 90 breaths/ min. It was found that significant improvement in accuracy can be achieved by employing particle filters, and that the combined OPS-PF employing either the NN or WNN likelihood function achieved the best results for all respiratory rates considered in this paper. The main advantage of the combined OPS-PF with either the NN or WNN likelihood function is that for the first time, respiratory rates as high as 90 breaths/min can be accurately extracted from pulse oximeter recordings.
Problematizing the Familiar (2004)

The article is the result of tutor reflection and considers some dilemmas faced by Deaf students as they seek to work with d/Deaf and non-deaf people using a qualitative paradigm.1 Emerging themes are presented which challenge the appropriateness of academic research language in relation to sign language and the competing notions of Deaf people as invariably ‘experts’ or ‘the other’. Some case examples are given to stimulate debate. The position of Deaf researchers is related to that of ‘subalterns’ (Ladd, 2003) and seen as potentially ‘emancipatory’ (Truman et al., 2000). The article concludes by seeding the development of a new and critical paradigm of social work research among Deaf researchers and respondents within the seventh moment (Denzin, 2002) and therefore posing the question of how this will be achieved for students whose preferred mode of communication is sign language.
Asymptotic theorems of sequential estimation-adjusted urn models (2006)

The Generalized Pólya Urn (GPU) is a popular urn model which is widely used in many disciplines. In particular, it is extensively used in treatment allocation schemes in clinical trials. In this paper, we propose a sequential estimation-adjusted urn model (a nonhomogeneous GPU) which has a wide spectrum of applications. Because the proposed urn model depends on sequential estimations of unknown parameters, the derivation of asymptotic properties is mathematically intricate and the corresponding results are unavailable in the literature. We overcome these hurdles and establish the strong consistency and asymptotic normality for both the patient allocation and the estimators of unknown parameters, under some widely satisfied conditions. These properties are important for statistical inferences and they are also useful for the understanding of the urn limiting process. A superior feature of our proposed model is its capability to yield limiting treatment proportions according to any desired allocation target. The applicability of our model is illustrated with a number of examples.
Development of human umbilical vein endothelial cell (HUVEC) and human umbilical vein smooth muscle cell (HUVSMC) branch/stem structures on hydrogel layers via biological laser printing (BioLP) (2010)

Angiogenesis is one of the prerequisite steps for viable tissue formation. The ability to influence the direction and structure in the formation of a vascular system is crucial in engineering tissue. Using biological laser printing (BioLP), we fabricated branch/stem structures of human umbilical vein endothelial cells (HUVEC) and human umbilical vein smooth muscle cells (HUVSMC). The structure is simple as to mimic vascular networks in natural tissue but also allow cells to develop new, finer structures away from the stem and branches. Additionally, we printed co-culture structures by first depositing only HUVECs, followed by 24 h incubation to allow for adequate cell-cell communication and differentiation into lumina; these cell printed scaffold layers were then removed from incubation and inserted into the BioLP apparatus so that HUVSMCs could be directly deposited on top and around the previously printed HUVEC structures. The growth and differentiation of these co-culture structures was then compared to the growth of printed samples with either HUVECs or HUVSMCs alone. Lumen formation was found to closely mimic the original branch and stem structure. The beginning of a network structure is observed. HUVSMCs acted to limit HUVEC over-growth and migration when compared to printed HUVEC structures alone. HUVSMCs and HUVECS, when printed in close contact, appear to form cell-cell junctions around lumen-like structures. They demonstrate a symbiotic relationship which affects their development of phenotype when in close proximity of each other. Our results indicate that it is possible to direct the formation and growth of lumen and lumen network using BioLP.
Suppression of backreflection error in resonator integrated optic gyro by the phase difference traversal method (2016)

The phase difference traversal (PDT) method is proposed to suppress the backreflection-induced error in resonator integrated optic gyro (RIOG). Theoretical analysis shows that the backreflection-induced zero-bias fluctuation is periodical and sine/cosine-like. By forcing the phase difference between the CW and CCW incident light to traverse the interval [0, 2π] repeatedly and rapidly enough, the fluctuation can be low-pass filtered and, hence, the backreflection-induced error can be effectively suppressed. A RIOG apparatus is built up, with multi-wave hybrid phase modulation to traverse the phase difference and in-phase modulation to set the operation point. A short-term bias stability of 0.0055 deg/s and a long-term bias stability of 0.013 deg/s are successfully demonstrated which, to the best of our knowledge, are the best results reported to date for the buried-type silica waveguide ring resonator-based RIOG.
Identification of Potential Mechanisms for Regulation of p115 RhoGEF through Analysis of Endogenous and Mutant Forms of the Exchange Factor (2001)

Rho GTPases play a fundamental role in numerous cellular processes that are initiated by extracellular stimuli including agonists that work through G protein-coupled receptors. A direct pathway for such regulation was elucidated by the identification of p115 RhoGEF, an exchange factor for RhoA that is activated through its RGS domain by G alpha(13). Endogenous p115 RhoGEF was found mainly in the cytosol of serum-starved cells but partially localized to membranes in cells stimulated with lysophosphatidic acid. Overexpressed p115 RhoGEF was equally distributed between membranes and cytosol; either the RGS or pleckstrin homology domain was sufficient for this partial targeting to membranes. Removal of the pleckstrin homology domain dramatically reduced the in vitro rate of p115 RhoGEF exchange activity. Deletion of amino acids 252--288 in the linker region between the RGS domain and the Dbl homology domain or of the last 150 C-terminal amino acids resulted in non-additive reduction of in vitro exchange activity. In contrast, p115 RhoGEF pieces lacking this extended C terminus were over 5-fold more active than the full-length exchange factor in vivo. These results suggest that p115 RhoGEF is inhibited in the cellular milieu through modification or interaction of inhibitory factors with its C terminus. Endogenous p115 RhoGEF that was immunoprecipitated from cells stimulated with lysophosphatidic acid or sphingosine 1-phosphate was more active than when the enzyme was immunoprecipitated from untreated cells. This indicates an additional and potentially novel long lived mechanism for regulation of p115 RhoGEF by G protein-coupled receptors.
Composites of Acrylonitrile-Butadiene-Styrene Filled with Wood-Flour (2007)

This study examined both the use of acrylonitrile-butadiene-styrene (ABS) as a plastic matrix for wood-plastic composites (WPCs) and the effect of impact modification on the mechanical properties of ABS/wood-flour composites. Blends of ABS filled with wood flour (both pine and maple) were processed into profile shape using a conical twin-screw extruder and the mechanical properties of the resulting composites were characterised and compared to WPCs made with polyolefins (HDPE and PP) and rigid PVC matrices. Generally, WPCs made with ABS matrix outperformed their polyolefin counterparts in both flexural strength and modulus, whereas ABS-based composites had inferior strength but greater modulus than those made with rigid PVC. The impact strength of ABS/wood-flour composites was below that of wood plastic composites made with polyolefins. However, impact modification with acrylonitrile-butadiene-styrene terpolymers had some effect in toughening of the ABS/wood-flour composites.
Modulators of dyslipidaemia (1998)

Coronary heart disease (CHD) is the leading cause of morbidity and mortality in most developed nations and atherosclerotic cardiovascular disease accounts for approximately one-half of all deaths due to CHD. Dyslipidaemias, which include various combinations of hypercholesterolaemia, hypertriglyceridaemia and hypoalphalipoproteinaemia, are major risk factors for atherosclerotic CHD. Current therapy largely treats hypercholesterolaemia, as reflected in the sales of 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors (HMGR-Is, statins) which account for a worldwide market share of 88%. The fibrates, which account for 9% of worldwide market share, effectively treat hypertriglyceridaemia but have inconsistent effects on hypercholesterolaemia and hypoalphalipoproteinaemia. Niacin, although an effective treatment for dyslipidaemias, suffers from a poor side-effect profile and therefore poor compliance. Moreover, niacin is not recommended for diabetics, a population in which atherosclerotic cardiovascular disease due largely to dyslipidaemia is the most common cause of death. Although additional strategies to reduce hypercholesterolaemia are still under pursuit (e.g., cholesterol absorption inhibitors, acyl-CoA:cholesterol acyltransferase [ACAT] inhibitors, squalene synthetase [SQS] inhibitors), attention has shifted to therapeutic strategies that affect hypertriglyceridaemia and/or hypoalphalipoproteinaemia in addition to hypercholesterolaemia (e.g., very low-density lipoprotein [VLDL] assembly/secretion inhibitors, thyromimetics, oestrogen agonists, peroxisome proliferator activated receptor [PPAR] activators, cholesterol ester transfer protein [CETP] inhibitors, apolipoprotein A1 [apoA1] production stimulators, lipoprotein lipase [LPL] activators) and these strategies are being aggressively pursued. The status of current efforts in these emerging therapeutic areas is described below.
Influence of a novel β‐nucleating agent on the structure, morphology, and nonisothermal crystallization behavior of isotactic polypropylene (2008)

Abstract The crystalline structure, morphology, and nonisothermal crystallization behavior of isotactic polypropylene (iPP) with and without a novel rare earth‐containing β‐nucleating agent (WBG) were investigated with wide‐angle X‐ray diffraction, polar optical microscopy, and differential scanning calorimetry. WBG could induce the formation of the β form, and a higher proportion of the β form could be obtained by the combined effect of the optimum WBG concentration and a lower cooling rate. The content of the β form could reach more than 0.90 in a 0.08 wt % WBG nucleated sample at cooling rates lower than 5°C/min. Polar optical microscopy showed that WBG led to substantial changes in both the morphological development and crystallization process of iPP. At all the studied cooling rates, the temperature at which the maximum rate of crystallization occurred was increased by 8–11°C in the presence of the nucleating agent. An analysis of the nonisothermal crystallization kinetics also revealed that the introduction of WBG significantly shortened both the apparent incubation period for crystallization and the overall crystallization time. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Design and evaluation of a Twitter hashtag recommendation system (2014)

Twitter has evolved into a powerful communication and information sharing tool used by millions of people around the world to post what is happening now. A hashtag, a keyword prefixed with a hash symbol (#), is a feature in Twitter to organize tweets and facilitate effective search among a massive volume of data. In this paper, we propose an automatic hashtag recommendation system that helps users find new hashtags related to their interests.