gebhart/patrepeval huggingface dataset:
New tetrahydroisoquinoline-based P-glycoprotein modulators: decoration of the biphenyl core gives selective ligands (2018)

P-glycoprotein (P-gp, MDR1) is a membrane transporter expressed in several regions of our body. It plays a crucial defense role as it mediates the efflux of hundreds of potentially toxic substances. However, P-gp is one of the main causes of failure in cancer chemotherapy, as a number of chemotherapeutic agents are P-gp substrates. Another interesting implication concerns the correlation between P-gp expression impairment and the onset of several central nervous system pathologies such as Alzheimer's and Parkinson's diseases. In view of these considerations, in the present study, a new series of P-gp modulators have been designed, synthesized and evaluated for their activity towards P-gp and two other sister proteins (BCRP and MRP1). The compounds, structurally correlated to the potent but non-selective P-gp inhibitor <b>MC70</b> [4'-(6,7-dimethoxy-3,4-dihydro-1<i>H</i>-isoquinolin-2-ylmethyl)biphenyl-4-ol], proved fairly selective towards P-gp, with a potency in the micromolar range. Compounds <b>5a</b>, <b>5d</b> and <b>12d</b> proved capable of restoring doxorubicin toxicity in resistant cancer cells.
Design and advanced characterization of quercetin-loaded nano-liposomes prepared by high-pressure homogenization (2023)

Quercetin-loaded nano-liposomes were prepared by high-pressure homogenization (HPH) at different pressures (up to 150 MPa) and number of passes (up to 3) to define the best processing conditions allowing the lowest particle size and the highest encapsulation efficiency (EE). The process at 150 MPa for 1 pass was the best, producing quercetin-loaded liposomes with the lowest particle size and 42% EE. Advanced techniques (multi-detector asymmetrical-flow field flow fractionation and analytical ultracentrifugation combined with transmission electron microscopy) were further used for the characterization of the liposomes which were oblong in shape (ca. 30 nm). Results highlight the need for several techniques to study nano-sized, polydisperse samples. The potential of quercetin-loaded liposomes against colon cancer cells was demonstrated. Results prove that HPH is an efficient and sustainable method for liposome preparation and highlight the remarkable role of process optimisation as well as the powerfulness of advanced methodologies for the characterisation of nano-structures.
Tunnel FETs using Phosphorene/ReS2 heterostructures (2019)

2D materials based heterostructures are potential candidates for Tunnel FETs (TFET) due to their self- passivated Van der Waals surfaces, which are ideally free from traps at the heterojunction interface [1]. In this study, we experimentally demonstrate heterostructure TFETs of ReS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and Phosphorene. ReS2 shows n-type behavior [2] and Phosphorene either an ambipolar or p-type behavior depending on the flake thickness and work function of contact metal [3]. The band alignment of Phosphorene- ReS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> heterostructure is either staggered or near broken gap configuration depending on the flake thickness [4]. Band-to-band tunneling (BTBT) and its signature Negative Differential Resistance (NDR) have been observed previously in ReS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Phosphorene heterostructures [5]. We show new insights on NDR and Negative Differential Transconductance (NDT) at different temperatures and their dependence on the thickness of ReS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and Phosphorene flakes and hence their doping concentration.
Development of mass spectrometric methods for proteomics analysis utilizing gas-phase chemistry and ultraviolet photodissociation (2016)

The utility of ultraviolet photodissociation (UVPD) in comparison to higher-energy collisional dissociation (HCD) to provide sequence coverage was assessed for various protein cation charge states and sizes. UVPD provided consistently higher sequence coverages through more uniform fragment ion distribution along the protein sequence. HCD provided lower sequence coverage values as well as more preference towards cleavage at the most labile bonds. Assessment of coverage dependence at lower charge states was also performed through proton transfer reactions (PTR) with ion parking. Overall, HCD provided preferential cleavage C-terminal to amino acids with acidic sidechains and N-terminal to proline, while UVPD provided more evenly distributed cleavage sites with enhancement near proline and phenylalanine.\nUsing UVPD as a structural analysis tool, PTR was assessed for perturbations to native-like structure of various protein complexes. Through comparison of UVPD fragment intensities, spectra of protein complexes generated through PTR showed little difference to spectra obtained from native-like protein spectra. Following this, PTR-UVPD was applied to elucidate fragment origins of an ambiguous homodimeric protein complex, otherwise displaying complex a complex mass spectrum of overlapping species.\nA novel approach to performing UVPD using light emitting diodes (LEDs) was explored involving the engineering of a new planar ion trap. Commercially available ultraviolet LEDs emitting photons with wavelengths ranging from 255 to 275 nm were obtained and interfaced with the new ion trap. Sequestration of sample ions in a small spot allowed optimization of overlap with LED photons and resulting fragmentation efficiencies were assessed. Once optimized, LED-UVPD was successfully performed for electron photodetachment (EPD) of single stand DNA and tyrosine sidechain cleavage of a peptide.\nCustom instrument function was enabled to automatically resonantly eject un-dissociated precursor ions following UVPD and was applied during liquid chromatography (LC) bottom-up proteomics experiments. Through ejection of uninformative, un-dissociated precursor ions, detrimental mass shifting effects caused by increasing the number of charges during spectrum acquisition were relieved. It was observed that performing PE-UVPD resulted in higher protein identification confidence values than for UVPD alone for an E. coli whole cell lysate digest.
Catalytic syntheses of silicon nanowires and silica nanotubes (2005)

Silicon nanowires (SiNWs) have been fabricated with metal- and SiO/sub 2/-catalyses assisted by laser ablation. In the growths of single-crystalline SiNWs by metal-catalysts, it is found that SiNWs are along <111> growth direction; however, the <112> growth direction is resulted in the SiO/sub 2/-catalyzed SiNWs. Pressure effect on the longitudinal and transverse growing rates of these SiNWs has also been examined. With the chemical vapor deposition method, the silica nanotubes (SiO/sub 2/NTs) could be achieved with Au nanoparticles as catalysts. From electron diffraction pattern, it shows that the SiO/sub 2/NTs are amorphous and the possible growth mechanism would be discussed.
iNET Networking Standards Test Bed (2009)

ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada
Glutathione in Synechocystis 6803 (2011)

Glutathione (GSH) is a low molecular weight thiol compound that plays many roles in photosynthetic organisms. We utilized a ∆gshB (glutathione synthetase) mutant strain as a tool to evaluate the role of GSH in the cyanobacterium Synechocystis sp. PCC 6803 (hereafter Synechocystis 6803), a model photosynthetic organism. The ∆gshB mutant does not synthesize glutathione, but instead accumulates the GSH precursor, gamma-glutamylcysteine (gamma-EC), to millimolar levels. We found that gamma-EC was sufficient to permit cellular proliferation during optimal conditions, but not when cells were exposed to conditions promoting oxidative stress. Furthermore, we found that many factors affecting growth rate and photosynthetic activities strongly influenced cellular thiol content. Here, we are providing some additional insights into the role of GSH and gamma-EC in Synechocystis 6803 during conditions promoting oxidative stress.
ATR‐IR spectra of MBS impact modified and unmodified rigid PVC processed in different ways (1988)

Abstract The surface IR absorption characteristics of MBS impact modified and unmodified PVC specimens prepared in various ways were determined by ATR‐FTIR techniques. These specimens include compression molded plaques and blow molded bottles. In addition and as a reference point, the IR spectrum of a solution cast film of unmodified PVC was obtained in the transmission mode. The IR spectra in the C‐Cl stretching region for unmodified plaques, i.e. 560 to 750 cm −1 , were curve fitted to seven Lorenz functions centered at the literature frequencies, except for one band which was changed from 639 to 636.5 cm −1 . Two additional bands (699 and 759 cm −1 ) were assumed to represent the modifier absorption in modified plaques and bottles. Only peak intensities and band widths were allowed to vary in the curve fitting process. Deconvoluted spectra of selected specimens support the number and location of the absorption peaks. Though these surface spectral changes can be represented in terms of surface configurational partitioning that occurred during processing, a more likely explanation is that conformational changes in the PVC polymer chain has occurred on the surface. Quantities representing the configuration of PVC polymer chains such as non‐syndiotacticity (NSS) or the fraction of PVC backbone carbon atoms that are found in the trans conformation (TRANS) were estimated from Lorenz parameters. NSS and TRANS were found to depend on processing conditions as well as the nature of the modifier. These results are discussed in terms of practical impact tests such as n‐Izod and falling bottle drop tests.
Enhanced sensitivity for the detection of trace gases using multiple line integrated absorption spectroscopy (2009)

We describe a technique that enhances the sensitivity of a spectrometer for trace gas detection employing an external cavity continuously tunable CW quantum cascade laser and integrating the absorption spectra across multiple lines of the species. We demonstrate the power of this method by continuously recording the absorption spectra of NO2 across the R branch from 1628.8 to 1634.5 cm(-1). By integrating the resulting spectra, the detection sensitivity of NO2 is improved by a factor of 15 compared to the sensitivity achieved using single line laser absorption spectroscopy with the same apparatus. This procedure offers much shorter data acquisition times for the real-time monitoring of trace gas species compared to adding repeated scans of the spectra to improve the signal-to-noise ratio.
Tagommenders (2009)

Tagging has emerged as a powerful mechanism that enables users to find, organize, and understand online entities. Recommender systems similarly enable users to efficiently navigate vast collections of items. Algorithms combining tags with recommenders may deliver both the automation inherent in recommenders, and the flexibility and conceptual comprehensibility inherent in tagging systems. In this paper we explore tagommenders, recommender algorithms that predict users' preferences for items based on their inferred preferences for tags. We describe tag preference inference algorithms based on users' interactions with tags and movies, and evaluate these algorithms based on tag preference ratings collected from 995 MovieLens users. We design and evaluate algorithms that predict users' ratings for movies based on their inferred tag preferences. Our tag-based algorithms generate better recommendation rankings than state-of-the-art algorithms, and they may lead to flexible recommender systems that leverage the characteristics of items users find most important.
NPRF &#x2014; Our view to novel forensic multimedia data analysis (2014)

The increasing use of digital media in daily life has resulted in a need for novel multimedia data analysis for forensic purposes. Processing multimedia documents for police investigations or as pieces of evidence in courts of law entails that their interpretation must be reliable, trustworthy, and efficient in terms of human time and other required resources. Accomplishing this task will help greatly to speed up investigations and judicial processes, making them more effective. In this paper, we present our views on processing techniques for varied multimedia sources. In particular, we focus on speech, video and images, handwriting, and text documents. The new techniques we propose will form a toolkit to be used in law force investigation or in a court of law, to extract information and evidence from different multimedia sources. This toolkit will support the user in a way that will lead to standardisation and (semi-) automation in the analysis of forensic data.
Relationship Between Molecular Subtype of Invasive Breast Carcinoma and Expression of Gross Cystic Disease Fluid Protein 15 and Mammaglobin (2011)

We investigated the expression of gross cystic disease fluid protein 15 (GCDFP) and mammaglobin (MGB) by immunohistochemical analysis in 71 invasive breast carcinomas (IBCs) subtyped into luminal (A and B), HER2, basal-like carcinoma (BLC), and unclassified triple-negative carcinoma (UTNC) by established surrogate immunohistochemical profiles. GCDFP and MGB were less likely to be expressed in BLC than in HER2 cancers (P = .000021 and P = .013, respectively) or luminal cancers (P = .00002 and P = .00008, respectively). However, the difference in GCDFP or MGB expression between HER2 and luminal cancers was not significant (P = 1.0 and P = .671, respectively). Our results suggest that luminal cancers demonstrate similar degrees of apocrine differentiation as HER2 cancers. Most BLCs and UTNCs are negative for MGB and GCDFP. Correlation with clinical findings may be needed to exclude the possibility of a metastasis to the breast when BLCs or UTNCs are encountered in a limited sample such as a core biopsy sample.
Retinal OCT imaging based on actively mode locked akinetic swept source at 1080 nm wavelength (Conference Presentation) (2019)

Optical coherence tomography (OCT) is a noninvasive imaging modality which can provide cross-sectional imaging of the tissues in high-resolution. Especially in retina imaging, the OCT becomes one of the most valuable imaging tools for the diagnostics of the eye diseases. Considering the scattering and absorption properties of the eye, the 1000 nm OCT system is preferred for the retina image. In this study, we describe an akinetic swept source OCT system based on pulse-modulated active mode locking (AML) fiber laser at the 1080 nm wavelength region for in-vivo human retina imaging. The akinetic AML wavelength swept fiber laser is constructed with polarization maintaining fiber which has average linewidth of 0.625 nm, a spectral bandwidth of 81.15 nm and a duty ratio of 90 % without buffering method. We successfully obtained in-vivo human retina images using proposed OCT system without the additional k-clock and the frequency shifter providing wide field of view of 43.1º. The main retina layers such as RPE can be distinguished through the OCT image with axial resolution of 6.3 m.
Gray matter density loss in essential tremor: a lobule by lobule analysis of the cerebellum (2017)

We showed that ET cases with various forms of cranial tremor differed from controls with respect to cerebellar GM density, with evidence of GM reduction across multiple cerebellar regions. Additional work, using a lobule-by-lobule approach, is needed to confirm these results and precisely map the regional differences in ET cases, subgroups of ET cases, and controls.
Comparison of multivariate methods for quantitative determination with transmission Raman spectroscopy in pharmaceutical formulations (2010)

Abstract The use of transmission Raman spectroscopy for quantitative assessment of pharmaceutical tablets using different multivariate approaches was investigated. Although Raman spectroscopy is most often used in backscatter geometry, in this paper a transmission approach was utilized, where the Raman scattered light is detected at the back side of the tablets. Raman spectra were recorded using a dispersive spectrometer with a 785 nm excitation laser and a typical exposure time of 10 s. The tablets were loaded to a 32‐position sample rack and measured by an automated procedure. Tablets with variation in content of paracetamol were manufactured. The data were evaluated with respect to the content of paracetamol, using partial least squares (PLS) and multivariate curve resolution (MCR). In addition, classical least squares (CLS), curve fitting and peak ratios were included for comparison. MCR, CLS and PLS gave comparable results with relative prediction errors for an independent test set in the range of 2.4–3.4%. Curve fitting and peak ratios gave higher prediction errors, typically around 4 and 6%, respectively. Interestingly, quantitative models based on only two samples in the calibration sets resulted in almost as good results as if half of the available tablets were included in the calibration. Due to the simple calibration models and the selective Raman spectra, the loadings and spectra were easy to interpret for all the multivariate methods used in this paper. The implications for content uniformity analysis by using transmission Raman in this simplified approach are discussed. Copyright © 2010 John Wiley &amp; Sons, Ltd.
ChemInform Abstract: Intramolecular 1,3‐Dipolar Cycloaddition at the Periphery of Heterocyclic Systems. Part 4. A Facile Cyclopropane Ring Formation by the Thermal Reaction of 2‐(Alk‐2‐enylamino)‐4‐oxo‐4H‐pyrido(1,2‐a) pyrimidine‐3‐carboxaldehydes with Tosylhydrazine. (1997)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Blind adaptive interference suppression for direct-sequence CDMA (1998)

Direct sequence (DS) code division multiple access (CDMA) is a promising technology for wireless environments with multiple simultaneous transmissions because of several features: asynchronous multiple access, robustness to frequency selective fading, and multipath combining. The capacity of DS-CDMA systems is interference-limited and can therefore be increased by techniques that suppress interference. In this paper, we present developments in interference suppression using blind adaptive receivers that do not receive knowledge of the signal waveforms and propagation channels of the interference, and that require a minimal amount of information about the desired signal. The framework considered generalizes naturally to include additional capabilities such as receive antenna diversity. The most powerful application of the methods described here is for linearly modulated CDMA systems with short spreading waveforms (i.e., spreading waveforms with period equal to the symbol interval), for which they provide substantial performance gains over conventional reception. Implications for future system design due to the restriction of short spreading waveforms and directions for further investigation are discussed.
Peptide Bond Formation in the Protonated Serine Dimer Following Vacuum UV Photon‐Induced Excitation (2023)

Possible routes for intra-cluster bond formation (ICBF) in protonated serine dimers have been studied. We found no evidence of ICBF following low energy collision-induced dissociation (in correspondence with previous works), however, we do observe clear evidence for ICBF following photon absorption in the 4.6-14 eV range. Moreover, the comparison of photon-induced dissociation measurements of the protonated serine dimer to those of a protonated serine dipeptide provides evidence that ICBF, in this case, involves peptide bond formation (PBF). The experimental results are supported by ab initio molecular dynamics and exploration of several excited state potential energy surfaces, unraveling a pathway for PBF following photon absorption. The combination of experiments and theory provides insight into the PBF mechanisms in clusters of amino acids, and reveals the importance of electronic excited states reached upon UV/VUV light excitation.
Gonadotrophin‐inhibitory hormone and its mammalian orthologue RFamide‐related peptide‐3: Discovery and functional implications for reproduction and stress (2018)

At the turn of the millennium, a neuropeptide with pronounced inhibitory actions on avian pituitary gonadotrophin secretion was identified and named gonadotrophin-inhibitory hormone (GnIH). Across bird species, GnIH acts at the level of the pituitary and the gonadotrophin-releasing hormone (GnRH) neuronal system to inhibit reproduction. Subsequent to this initial discovery, orthologues of GnIH have been identified and characterised across a broad range of species. In many vertebrates, the actions of GnIH and its orthologues serve functional roles analogous to those seen in birds. In other cases, GnIH and its orthologues exhibit more diverse actions dependent on sex, species, season and reproductive condition. The present review highlights the discovery and functional implications of GnIH across species, focusing on research domains in which the significance of this neuropeptide has been explored most.
Thoracic Outlet Syndrome Part II: Consensus on the Management of Neurogenic Thoracic Outlet Syndrome by the European Association of Neurosurgical Societies’ Section of Peripheral Nerve Surgery (2022)

Our work may help to improve clinical decision-making among the neurosurgical community and may guide nonspecialized or inexperienced neurosurgeons with initial patient management before patient referral to a specialized center.