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Summary: This paper proposes an integrated damping system that aims at providing relatively high damping levels through the mobilization of a proportion of the structure's own mass. This offers significantly higher mass levels and, consequently, considerably more damping compared to conventional tuned mass dampers. Fluid viscous dampers are used to control accelerations in parallel with springs to resist the static loads applied to the moving mass. The advantages of employing relatively large mass levels in achieving considerable damping and reducing sensitivity to tuning are first analyzed using an idealized two degree of freedom structural representation. This is then followed by a description of the proposed "integrated damping system," which is illustrated through a case study of a 250‐m tall building. The benefits of the proposed damping system are demonstrated through several numerical parametric assessments, as well as a selected suite of earthquake records. For the adopted case study, it is shown that, besides reducing the level of perceivable accelerations, the use of the suggested arrangement can offer an equivalent damping exceeding 50% of the critical damping, resulting in more than 40% reduction in the wind loads as well as over 60% reduction in displacement and acceleration response under seismic excitations. [ABSTRACT FROM AUTHOR]

Objective: Chronic pain is a prevalent condition which has a significant effect on the lives of those it impacts. High‐frequency 10 kHz spinal cord stimulation (10 kHz SCS) has been shown to provide paresthesia‐free pain relief for a wide variety of pain indications. This article summarizes the current and emerging data as they relate to the clinical use of the therapy in various pain syndromes. Methods: A literature search was conducted using the PubMed electronic database using keywords related to 10 kHz SCS. The database was queried from 2013 to May 2019. Articles reporting clinical studies that included human subjects permanently treated with 10 kHz SCS (Senza® system) were included in the review. Recent and relevant conference proceedings known to the authors were also included. Results: The selected literature demonstrated significant evidence for the efficacy of 10 kHz SCS in treating chronic back and leg pain (CBLP), including a randomized, controlled trial as well as prospective and retrospective studies. One‐year follow‐up responder rates (pain relief ≥50%) ranged from 60% to 80%. Other studies and case series showed promising outcomes in specific conditions, including nonsurgical refractory back pain, neuropathic limb pain, complex regional pain syndrome, chronic widespread pain, chronic pelvic pain, and intractable headache. Subgroup analyses also pointed toward the potential of 10 kHz SCS being successful when low‐frequency SCS has failed. The vast majority of these studies reported improved quality of life (QOL) metrics and/or reduced opioid consumption. Conclusions: Level I evidence already exists for the efficacy of 10 kHz SCS in treating CBLP, supported by real‐world clinical experience. Other studies demonstrate the potential of the therapy across a range of chronic pain etiologies, although larger confirmatory studies are recommended. Overall, the literature suggests that the therapy is associated with improved QOL as well as reduced opioid consumption. [ABSTRACT FROM AUTHOR]

Background: Primary squamous cell carcinoma of the thyroid (ThySCC) is a rare cancer, primarily described only in case reports. We aimed to characterize the prognosis of ThySCC and compare its oncologic behavior to other thyroid malignancies. Methods: The National Cancer Database was queried to identify patients with ThySCC, papillary, tall cell variant, poorly differentiated (PDTC), and anaplastic (ATC) subtypes of thyroid cancer treated from 2004 to 2015. Demographics, tumor characteristics, and treatments were compared by tumor type and assessed to identify independent predictors of overall survival (OS). Results: Of 123,684 patients included, 314 had ThySCC. ThySCC patients had a 5-year OS of 17.7%, more closely resembling ATC (8.3%) than PDTC or PTC. ThySCC and ATC patients had similar demographics, except ThySCC patients who were younger (68.0 vs. 70.2 years, p < 0.01). ThySCC tumors were smaller (mean 53.5 ± 45.7 vs. 69.5 ± 75.2 mm) with less frequent extrathyroidal extension (ETE) (64.0% vs. 73.8%), lymphovascular invasion (8.3% vs. 12.3%), and positive margins (22.0% vs. 28.3%) compared to ATCs (p < 0.05). ETE [HR 3.1 (95% CI 1.5–6.4), p < 0.05] and lymph node metastases [HR 2.2 (95% CI 1.2–4.0) p < 0.05] were independently associated with worse OS for ThySCC patients. Both ThySCC and ATC patients had similar surgical success rates, with R1 resection possible in 37.3% versus 35.0% of patients, respectively (p < 0.05). However, in contrast to ATC patients, adjuvant therapy was not associated with improved OS for ThySCC patients after complete resection. Conclusions: ThySCC has a poor prognosis, similar to ATC, but with fewer aggressive features and no apparent survival benefit with adjuvant therapy after complete macroscopic surgical resection. [ABSTRACT FROM AUTHOR]

Novel BiOF/TiO2 heterostructures with controlled amounts of BiOF and TiO2 have been successfully synthesized via a simple solid‐state sintering method. The structural, morphological and optical properties were analyzed using several characterization techniques. A shift of the TiO2 absorption edge toward the visible region was observed. The optimal molar ratio of BiOF/TiO2 was found to be (1:3) with a photodegradation percentage of 91.2 % and it was 7 and 5 times more efficient than that of pure BiOF or TiO2 nanopowder, respectively. BiOF/TiO2 (1:3) heterojunction has showed high photodegradation stability for the Rh B photodegradation after three cycles. In the proposed photocatalytic mechanism, TiO2 absorbed the visible light and carried out the photocatalytic reaction owing to the decrease of its band gap value due to the formation of oxygen vacancies, while BiOF played an important role in the charge separation process due to the intimate contact of the BiOF/TiO2 heterojunction. [ABSTRACT FROM AUTHOR]

There is a narrow window of opportunity between surgical scheduling and the operative date to optimize patients for an elective surgical procedure. Traditionally, preoperative care has involved extended routine testing batteries with intermittent referrals for medical clearance. These traditions are costly, inefficient, and yield no clear reduction in perioperative morbidity and mortality. Evidence, which has evolved over the past decade, suggests that optimal preoperative care requires a patient-centric, personalized, and often multidisciplinary approach. We present an up-to-date overview of this literature with a focus on the otolaryngologic surgical population. An algorithmic approach to preoperative patient assessment is also proposed in hopes of both optimizing patient outcome and streamlining routine clinical workflow. Laryngoscope, 130:38-44, 2020. [ABSTRACT FROM AUTHOR]

One‐dimensional (1D) nanostructured photocatalyst is a promising candidate for hydrogen (H2) generation, which can be used to deal with the energy crisis. Herein, novel 1D TiO2/CdS well‐hybridized nanofibers (NFs) were synthesized via in situ electrospinning method. These 1D hybrid NFs showed a high H2‐production rate of 2.32 mmol h−1 g−1 with an apparent quantum efficiency of 10.14 %, which was 35‐fold higher than that of pristine TiO2 NFs. X‐ray photoelectron spectroscopy (XPS) analysis and density functional theory calculation implied that the electrons transferred from CdS to TiO2 upon hybridization and created an internal electric field (IEF) pointing from CdS to TiO2. This IEF drove the photoexcited electrons in TiO2 to transfer toward CdS upon light irradiation as revealed by in situ irradiated XPS analysis, suggesting that a step‐scheme (S‐scheme) heterojunction was formed in the TiO2/CdS nanohybrids and greatly promoted the separation of electron‐hole pairs to foster efficient H2 photogeneration. The significant enhancement of photocatalytic activity was also benefited from the easy transfer for electrons in the 1D well‐distributed nanostructure of nanohybrids. This work presents a method for in situ preparing well‐distributed 1D NFs with high photocatalytic activity for H2 production via the S‐scheme pathways. [ABSTRACT FROM AUTHOR]

The nighttime limb intensity of diffuse auroral emission of CO2+ (B2Σu+ ‐ X2πg) Ultraviolet Doublet (UVD) is observed in the northern hemisphere of Mars during 17–21 December 2014 from Imaging Ultraviolet Spectrograph instrument onboard Mars Atmosphere and Volatile Evolution. We have used hybrid model and four‐dimensional yield spectrum approach based on Monte Carlo simulation to calculate the ionization rate, limb intensity, and ion and electron densities of diffuse aurora due to precipitation of solar energetic particle and proton‐hydrogen (H+‐H) fluxes in the nighttime ionosphere of Mars. It is found that the production rates of atmospheric ions (CO2+, N2+, and O+) are dominant in the upper ionosphere at about 100–150 km due to impact of H+‐H. The solar energetic particle formed auroral ionosphere (CO2+, NO+, and O+) in the middle ionosphere between 50 and 100 km due to precipitation of monoenergetic electrons of energies 25 to 100 keV. The simulated limb intensities of CO2+UVD due to impact of H+‐H and auroral electrons are compared with Imaging Ultraviolet Spectrograph observations. Our model results are overestimating the observations, but 100 keV electrons deposited maximum energy around 75 km, closer to the observed altitude of the maximum emission. The densities of upper ionosphere (O2+, NO+, and CO2+) due to impact of H+‐H are smaller by one to two orders of magnitude than that produced by auroral electrons in the middle ionosphere. Key Points: Causative mechanisms of diffuse auroraSEP electron and H+‐H precipitation on Mars [ABSTRACT FROM AUTHOR]

Diabetes mellitus is one of the most common endocrinopathies encountered in the perioperative period, and the pediatric population is increasingly using continuous subcutaneous insulin infusions for diabetes management. As these patients present for procedures or surgery requiring anesthesia, the anesthesia provider is charged with the task of managing these pumps perioperatively. Here, we review our experience from a large tertiary care academic medical center and propose recommendations for the perioperative management of children and adolescents with diabetes who use insulin pumps. [ABSTRACT FROM AUTHOR]

Investigations focusing on electrical energy storage capacitors especially the dielectric ceramic capacitors for high energy storage density are attracting more and more attention in the recent years. Ceramic capacitors possess a faster charge‐discharge rate and improved mechanical and thermal properties compared with other energy storage devices such as batteries. The challenge is to obtain ceramic capacitors with outstanding mechanical, thermal and storage properties over large temperature and frequencies ranges. ABO3 as a type of perovskites showed a strong piezoelectric, dielectric, pyroelectric, and electro‐optic properties useful as energy storage and environmental devices. CaCu3Ti4O12 (CCTO) perovskite with cubic lattice (Im3 symmetry) was discovered to have a colossal dielectric constant (104) that is stable over a wide range of frequencies (10 Hz–1 MHz) and temperature independence (100–300 K). The origin of this high dielectric constant is not fully established, specially because it is the same for single crystal and thin films. In this review, the history of CCTO will be introduced. The synthesis and the sintering approaches, the dopant elements used as well as the applications of CCTO will be reported. In addition to dielectrical properties useful to energy storage devices; CCTO could serve as photocatalytic materials with a very good performance in visible light. [ABSTRACT FROM AUTHOR]

In this work, NPC (nanoporous carbon) is purposely employed to accommodate the semiconductor CdSe QDs (quantum dots) in the absence of any capping agent to facilitate the visible-light photocatalyst CdSe QDs@NPC composite. CdSe QDs@NPC composite has been achieved by the facile method of the incipient-wetness deposition, and furthermore characterised by powder X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller, transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The results of TEM and HRTEM show that CdSe QDs are implanted into NPC and bound to several nanometres. Both X-ray diffraction and HRTEM indicate that the as-synthesised CdSe QDs belong to the cubic phase. The photocatalytic performance of CdSe QDs@NPC composite has been evaluated by degrading the RhB under visible-light irradiation. NPC as electron acceptor and transport channel can enhance the synergism of CdSe and NPC by improving the electron–hole separation. Furthermore, the photocatalytic mechanism exhibits that h+ and O2−• species are the decisive, active species in the degradation process of RhB. [ABSTRACT FROM AUTHOR]

The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) onboard Mars Express, which operates between 0.1 and 5.5 MHz, suffered from a complete blackout for 10 days in September 2017 when observing on the nightside (a rare occurrence). Moreover, the Shallow Radar (SHARAD) onboard the Mars Reconnaissance Orbiter, which operates at 20 MHz, also suffered a blackout for three days when operating on both dayside and nightside. We propose that these blackouts are caused by solar energetic particles of few tens of keV and above associated with an extreme space weather event between 10 and 22 September 2017, as recorded by the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Numerical simulations of energetic electron precipitation predict that a lower O2+ nighttime ionospheric layer of magnitude ~1010 m−3 peaking at ~90‐km altitude is produced. Consequently, such a layer would absorb radar signals at high frequencies and explain the blackouts. The peak absorption level is found to be at 70‐km altitude. Plain Language Summary: Several instrument operations, as well as communication systems with rovers at the surface, depend on radio signals that propagate throughout the atmosphere of Mars. This is the case also for two radars that are currently working in Mars' orbit, sounding the ionosphere, surface, and subsurface of the planet. In mid‐September 2017, a powerful solar storm hit Mars, producing a large amount of energetic particle precipitation over a 10‐day period. We have found that high‐energy electrons ionized the atmosphere of Mars, creating a dense layer of ions and electrons at ~90 km on the Martian nightside. This layer attenuated radar signals continuously for 10 days, stopping the radars to receive any signal from the planetary surface. In this work, we assess the properties of this layer in order to understand the implications of this kind of phenomenon for radar performance and communications. Key Points: A large space weather event caused negatively impacted radar performance for 10 daysSolar electron precipitation created a low ionospheric layer at ~90 km on the nightsideThe nightside ionization is comparable to dayside values [ABSTRACT FROM AUTHOR]

The persistent two‐peaked vertical structure of the Martian ionosphere is created by extreme and far ultraviolet radiation whose energies, respectively, determine their ionization altitude. A third low‐altitude transient layer (previously referred to as M3 or Mm) has been observed by radio occultation techniques and attributed to meteor ablation. However, recent remote sensing and in situ observations disfavor a meteoric origin. Here we propose an alternative hypothesis for these apparent layers associated with impact ionization from penetrating solar wind ions, previously observed as proton aurora. Localized ionization, occurring nonglobally at a given altitude range, breaks the symmetry assumed by the radio occultation technique, and creates electron layers apparently lower in the ionosphere than their true altitude. This may occur when the upstream bow shock is altered by a radial interplanetary magnetic field configuration, which allows the solar wind to penetrate directly into the thermosphere. This localized ionization hypothesis provides an explanation for apparent layers' wide variation in heights and their transient behavior. Moreover, this hypothesis is testable with new observations by the Mars Atmospheric and Volatile EvolutioN Radio Occultation Science Experiment in future Mars years. This hypothesis has implications for the ionospheres of Venus and Titan, where similar transient layers have been observed. Plain Language Summary: The ionosphere of a planet couples the neutral atmosphere to the exosphere and solar wind. Created by solar ionizing radiation, the ionosphere on the dayside of planet is expected to be hemispherically symmetric. When Mars Express discovered transient low‐altitude ionospheric layers in 2005, they were initially predicted to be due to meteor ablation. However, recent observations indicate that they are due to a geometric observational effect related to local, not hemispheric, ionization. Observations from three instruments on Mars Atmospheric and Volatile EvolutioN are used concurrently to understand this phenomenon. These transient layers have been observed at Venus and Titan as well, and this hypothesis indicates novel physics for those ionospheric systems. Key Points: Low‐altitude transient ionospheric layers may be explained by a geometric observational effect from localized, not hemispheric, ionizationA radio occultation of a transient ionospheric layer was obtained with observations of variable proton aurora and penetrating solar windTransient layers observed at Mars, Venus, and Titan are consistent with the presence of solar wind impact ionization at those planets [ABSTRACT FROM AUTHOR]

We report the first remote observation of nitric oxide (NO) densities on Mars. The Imaging Ultraviolet Spectrograph (IUVS) on NASA's Mars Atmosphere and Volatile Evolution (MAVEN) satellite observes NO γ band solar resonance fluorescence between 213.0 and 225.5 nm. We invert an average dayglow limb radiance profile to retrieve a number density profile between 80 and 130 km. The retrieved IUVS NO number density at 117 km is 5 times smaller than those measured by Viking mass spectrometers over 40 years ago but consistent with photochemical model results within the IUVS statistical uncertainty. These observations may therefore help to reconcile a longstanding problem in our understanding of NO photochemistry in the Martian upper atmosphere. We also report the first detection of the CO+ First Negative bands in the Martian dayglow near 219 nm. Plain Language Summary: Nitric oxide has been an important diagnostic for the effects of solar activity since its detection in the Earth's upper atmosphere over 50 years ago. We report the first remote observation of nitric oxide densities on Mars. The densities are five times smaller than those measured by Viking mass spectrometers upon entry into the atmosphere over 40 years ago. These new nitric oxide observations may help to reconcile a longstanding problem in our understanding of NO chemistry in the Martian upper atmosphere. Key Points: First remote observations of nitric oxide densities on MarsNitric oxide densities are a factor of five smaller than those reported by Viking over 40 years agoPhotochemical model results show much better agreement with the new remote observations than with Viking measurements [ABSTRACT FROM AUTHOR]

Magnetic topology is important for understanding the Martian plasma environment, including particle precipitation, energy transport, cold ion escape, and wave‐particle interaction. In this study, we combine two independent but complementary methods in order to determine magnetic topology based on superthermal electron energy and pitch angle distributions. This approach removes ambiguities that result from using either energy or pitch angle alone, providing a more accurate and comprehensive determination of magnetic topology than previous studies. By applying this combined technique, we are able to identify seven magnetic topologies, including four types of closed field lines, two types of open field lines, and draped. All seven topologies are present in the Mars environment and are mapped in longitude, latitude, solar zenith angle, and altitude with the combined technique near the terminator. We find that closed field lines with double‐sided loss cones are frequently present over stronger crustal field regions at higher altitudes. We also show that the cross‐terminator closed field lines are more spatially confined over strong crustal regions, likely connecting nearby magnetic crustal patches. In contrast, cross‐terminator closed loops over weak crustal regions have more distantly separated foot points, most likely connecting distant crustal patches. Key Points: A technique combining e‐ pitch angle and energy distribution is developed to most accurately infer up to seven magnetic topologies at MarsClosed magnetic loops with trapped electrons occur frequently over stronger crustal field regions at higher altitudesCross‐terminator closed loops are more spatially confined over strong crustal regions and distantly separated over weak crustal regions [ABSTRACT FROM AUTHOR]

Ag/mesoporous black TiO2 nanotubes heterojunctions (Ag‐MBTHs) were fabricated through a surface hydrogenation, wet‐impregnation and photoreduction strategy. The as‐prepared Ag‐MBTHs possess a relatively high specific surface area of ≈85 m2 g−1 and an average pore size of ≈13.2 nm. The Ag‐MBTHs with a narrow band gap of ≈2.63 eV extend the photoresponse from UV to the visible‐light and near‐infrared (NIR) region. They exhibit excellent visible‐NIR‐driven photothermal catalytic and photocatalytic performance for complete conversion of nitro aromatic compounds (100 %) and mineralization of highly toxic phenol (100 %). The enhancement can be attributed to the mesoporous hollow structures increasing the light multi‐refraction, the Ti3+ in frameworks and the surface plasmon resonance (SPR) effect of plasmonic Ag nanoparticles favoring light‐harvesting and spatial separation of photogenerated electron–hole pairs, which is confirmed by transient fluorescence. The fabrication of this SPR‐enhanced visible‐NIR‐driven Ag‐MBTHs catalyst may provide new insights for designing other high‐performance heterojunctions as photocatalytic and photothermal catalytic nanomaterials. Responding strongly: Ag/mesoporous black TiO2 hollow nanotube heterojunctions with wide‐spectrum response (≈2500 nm) were fabricated through a wet‐impregnation and photoreduction strategy. They exhibit excellent visible‐NIR‐driven photocatalytic and photothermal catalytic performance and long‐term stability, due to the synergistic effect of efficient surface hydrogenation, hollow structured TiO2, formation of heterojunctions, and surface plasmon resonance of Ag. [ABSTRACT FROM AUTHOR]

Understanding how the Mars plasma environment responds to space weather events provides insights into the early Sun‐Mars interaction and helps constrain the extrapolation of atmospheric loss back in time. The 2003 Halloween interplanetary coronal mass ejection (ICME) event is one of the most extreme space weather events encountered by Mars during the last two decades. Mars Global Surveyor's circular orbit at ∼400 km allows us to observationally study the magnetic topology response to this extreme event globally for the first time. We analyze the suprathermal electron data and magnetic field measurements from Mars Global Surveyor to infer magnetic topology before, during, and after this ICME event and quantify the variation of the topology over both weak and strong crustal regions and correlate the variation with the upstream dynamic pressure. Over weak crustal regions, more draped field lines and fewer closed field lines are observed under high dynamic pressures, implying a deeper interplanetary magnetic field penetration during the ICME event. Over dayside strong crustal regions, the dominant magnetic topology switches from closed field lines during quiet periods to open field lines during disturbed periods, suggesting more reconnection occurring between the crustal magnetic fields and interplanetary magnetic field. This mixed magnetic topological response is consistent with predictions from magnetohydrodynamic simulations for ICME events in previous studies. Key Points: We analyze Martian magnetic topology response to the 2003 Halloween ICME event and correlate the variation with upstream driversA deeper IMF penetration is found over weak crustal regions but more open field lines over strong crustal regions during the eventThis mixed magnetic topological response confirms previous predictions from MHD simulations for ICME events [ABSTRACT FROM AUTHOR]

Molybdenum trioxide (MoO3) represented an excellent photocatalytic performance with many applications, including degradation of organic contaminants and splitting of water. This paper presented a new route to synthesize MoO3 nanobelts with high aspect ratios and crystallinity by a hydrothermal technique. This work showed that the as‐synthesized nanobelts exhibited strong photocatalytic activity to degrade an organic dye of Rhodamine B (RhB) in aqueous solution under the exposure of the light source in the near infrared wavelength range, significantly improving the photocatalytic activity of the nanobelts. The results also showed that for a small concentration of RhB at 7.5 mg/L a complete photodegradation (for a given MoO3 nanobelts quantity of 0.1 g) can be reached after exposing for 60 min. For all concentrations of the RhB solution, the photodegradation exhibited an exponential dependence on the exposure time followed by a sudden shutdown, but no complete photodegradation can be reached. Also, the residual quantity of RhB in solution after the photocatalytic reaction was determined by the initial RhB concentration. The photocatalytic degradation can be interpreted by the pseudo–first‐order equation for the absorption of liquid/solid based on solid capacity; thus, photocatalytic degradation can be attributed to the interaction between the photoexcited electrons in the substrate and the antibonding orbital of the RhB in solution. The sudden shutdown was due to the inability of the photoexcited electrons in the substrate hopping to the antibonding orbital of RhB in the presence of the RhB intermediate products from the degraded RhB. In addition, this work showed that the photocatalytic reaction can be recovered after a thermal treatment of postreacted MoO3 nanobelts, enhancing the utilization efficiency of the catalysis. [ABSTRACT FROM AUTHOR]

Although solar activity is declining as the Sun approaches solar minimum, a series of large solar storms occurred in September 2017 that impacted both Earth and Mars. This was the largest event seen on the surface of Mars by the Radiation Assessment Detector on the Mars Science Laboratory Curiosity rover since landing in 2012 and was also observed as Ground Level Enhancement 72 on Earth, making it the first event observed to produce a Ground Level Enhancement on two planets at the same time. We present Radiation Assessment Detector observations of the surface radiation environment since 2012 and discuss the impact of the September 2017 events on this environment and its implications for human exploration and for mitigating the risk of space radiation and space weather events for future manned missions to Mars. Key Points: On 11 September 2017, MSL RAD observed the strongest solar particle event seen on the surface of Mars since landing in 2012Dose rates and neutral particle fluxes increased by factor of 2; proton and 4He fluxes increased by factor of 30 and 10, respectivelyIntegrated dose was only slightly greater than before the event, due to reduced quality factor during the event, and Forbush decrease after the event [ABSTRACT FROM AUTHOR]

Abstract: On 10 September 2017, some of the strongest solar activity occurred in association with active region 12673 (AR2673), including an X‐class solar flare and a fast coronal mass ejection. Although AR2673 was not centrally facing Mars, the activity impacted the local space weather conditions at Mars. We give an overview of observations obtained from the Mars Atmosphere and Volatile EvolutioN, Mars Science Laboratory, and Mars Express missions. Numerical results from the Wang‐Sheeley‐Arge (WSA)‐Enlil‐cone model together with Earth/L1 and STEREO‐A observations are also presented to provide some heliospheric context. We discuss the initial results on the space weather impacts at Mars, which include heating of the upper atmosphere by solar flare emissions, flare‐related enhancements of ion and neutral densities, solar energetic particles impacting the atmosphere and surface, bright emissions of a diffuse (global) aurora, deeply penetrating interplanetary magnetic fields over the Martian dayside, and enhanced atmospheric escape rates. [ABSTRACT FROM AUTHOR]

Thin films of the covellite phase of CuS are of special importance due to their properties for optoelectronic device applications. Their preparation by chemical solution methods could enable their deposition on flexible substrates at low temperature for large area applications. Successive Ionic Layer Adsorption and Reaction (SILAR) is a promising option because it is simple, inexpensive, and allows the control of thickness and composition. However, low crystalline CuS thin films have been reported so far. In this work, highly polycrystalline CuS thin films were successfully grown at room temperature by SILAR using CuSO4 and Na2S as the ionic solutions without post-deposition annealing. The films obtained at different SILAR cycles resulted in good appearance, uniformity, well adhered to the substrate, and presented the covellite structure as the predominant crystalline phase. X-ray diffraction analysis showed important details about the films growth evolution, which were in agreement with results from atomic force microscopy and ellipsometry. All the films exhibited low electrical resistivity in agreement with the metallic behavior observed in the infrared region of their transmittance spectra. These results demonstrate a direct method of obtaining highly polycrystalline CuS thin films at low temperature, which could open a new range of applications. [ABSTRACT FROM AUTHOR]

Differentiated thyroid cancer ( DTC) is the most common malignancy of the endocrine system. There has been a significant increase in its incidence over the past two decades attributable mainly to the use of more sensitive diagnostic modalities. Ultrasound-guided fine needle aspiration cytology is the mainstay of diagnosis of benign disorders and malignancy. However, approximately 20% of lesions cannot be adequately categorized as benign or malignant. In the postoperative setting, monitoring of thyroglobulin (Tg) levels has been employed for the detection of disease recurrence. Unfortunately, Tg antibodies are common and interfere with Tg measurement in this subset of patients. Despite this limitation, Tg remains the sole widely used thyroid cancer biomarker in the clinical setting. In an attempt to bypass antibody interference, research has focused mainly on mRNA targets thought to be exclusively expressed in thyroid cells. Tg and thyroid stimulating hormone receptor ( TSHR) mRNA have been extensively studied both for discerning between benign disease and malignancy and in postoperative disease surveillance. However, results among reports have been inconsistent probably reflecting considerable differences in methodology. Recently, micro RNA (mi RNA) targets are being investigated as potential biomarkers in DTC. Mi RNAs are more stable molecules and theoretically are not as vulnerable as mRNA during manipulation. Initial results have been encouraging but large-scale studies are warranted to verify and elucidate their potential application in diagnosis and postoperative surveillance of thyroid cancer. Several other novel targets, primarily mutations and circulating cells, are currently emerging as promising thyroid cancer circulating biomarkers. Although interesting and intriguing, data are limited and derive from small-scale studies in specific patient cohorts. Further research findings demonstrating their value are awaited with anticipation. [ABSTRACT FROM AUTHOR]

Hybrid materials, fabricated by the combination of inorganic and organic components, have potential applications in chemistry and are endowed with the advantages of both building elements. There are several types of intermolecular interactions present in these hybrid compounds, including electrostatic forces, π-π stacking and hydrogen-bonding interactions, the latter playing an important role in the construction of three-dimensional architectures and stabilizing supramolecular crystal structures. Analysis of the intermolecular interactions and their influence on packing modes therefore requires focused scientific attention. Four new organic-inorganic salts, namely 2-amino-4-methyl-3-nitropyridinium hydrogen sulfate, C6H8N3O2+·HSO4−, bis(2-amino-4-methyl-3-nitropyridinium) sulfate, 2C6H8N3O2+·SO42−, 2-amino-3-methylpyridinium hydrogen sulfate, C6H9N2+·HSO4−, and bis(2-amino-3-methylpyridinium) sulfate monohydrate, 2C6H9N2+·SO42−·H2O, have been synthesized and characterized by X-ray diffraction. The crystal structures are stabilized by intra- and intermolecular hydrogen bonds, as well as by weak π-π stacking and lp-π (lp is lone pair) interactions. Hirshfeld surface analysis was employed in order to study intermolecular interactions. [ABSTRACT FROM AUTHOR]

On the hypothesis that one carbon homologation of 4′-selenonucleosides might relieve the steric repulsion between cellular kinases and bulky selenium, 5′-homo-4′-Se-d4Ns, 3 a- e, as anti-HIV agents were designed and synthesized stereoselectively from d-gulonic γ-lactone, with the conversion of 2′,3′-diol into the olefin as the key step. The anti-HIV activity of all synthesized compounds, 5′-homo-4′-Se-d4Ns, was toxicity-dependent, unlike normal 4′-Se-d4Ns, which were inactive against HIV-1. This result indicates that 5′-homo-4′-Se-d4Ns might be phosphorylated by cellular kinases as per the hypothesis. [ABSTRACT FROM AUTHOR]

Tetrahydro-1-benzazepines have been described as potential antiparasitic drugs for the treatment of chagas disease and leishmaniasis, two of the most important so-called `forgotten tropical diseases' affecting South and Central America, caused by Trypanosoma cruzi and Leishmania chagasi parasites, respectively. Continuing our extensive work describing the structural characteristics of some related compounds with interesting biological properties, the crystallographic features of three epoxy-1-benzazepines, namely (2 SR,4 RS)-6,8-dimethyl-2-(naphthalen-1-yl)-2,3,4,5-tetrahydro-1 H-1,4-epoxy-1-benzazepine, (1), (2 SR,4 RS)-6,9-dimethyl-2-(naphthalen-1-yl)-2,3,4,5-tetrahydro-1 H-1,4-epoxy-1-benzazepine, (2), and (2 SR,4 RS)-8,9-dimethyl-2-(naphthalen-1-yl)-2,3,4,5-tetrahydro-1 H-1,4-epoxy-1-benzazepine, (3), all C22H21NO, and two 1-benzazepin-4-ols, namely 7-fluoro- cis-2-[( E)-styryl]-2,3,4,5-tetrahydro-1 H-1-benzazepin-4-ol, C18H18FNO, (4), and 7-fluoro- cis-2-[( E)-pent-1-enyl]-2,3,4,5-tetrahydro-1 H-1-benzazepin-4-ol, C15H20FNO, (5), are described. Some peculiarities in the crystallization behaviour were found, involving significant variations in the crystalline structures as a result of modest changes in the peripheral substituents in (1)-(3) and the occurrence of discrete disorder due to the molecular overlay of enantiomers with more than one conformation in (5). In particular, an interesting phase change on cooling was observed for compound (5), accompanied by an approximate fourfold increase of the unit-cell volume and a change of the Z′ value from 1 to 4. This transition is a consequence of the partial ordering of the pentenyl chains in half of the molecules breaking half of the symmetry axes observed in the room-temperature structure of (5). The structural assembly in all the title compounds is characterized by not only (N,O)-H...(O,N) hydrogen bonds, but also by unconventional C-H...O contacts, resulting in a wide diversity of packing. [ABSTRACT FROM AUTHOR]

A study of post-refinement absolute structure determination using previously published data was carried out using the CRYSTALS software package. We show that absolute structure determination may be carried out optimally using the analyses available in CRYSTALS, and that it is not necessary to have the separate procedures absolute structure determination and no interest in absolute structure as proposed by Flack [ Chimia (2014), 68, 26-30]. [ABSTRACT FROM AUTHOR]

It is well known that pyrimidin-4-one derivatives are able to adopt either the 1 H- or the 3 H-tautomeric form in (co)crystals, depending on the coformer. As part of ongoing research to investigate the preferred hydrogen-bonding patterns of active pharmaceutical ingredients and their model systems, 2-amino-6-chloropyrimidin-4-one and 2-amino-5-bromo-6-methylpyrimidin-4-one have been cocrystallized with several coformers and with each other. Since Cl and Br atoms both have versatile possibilities to interact with the coformers, such as via hydrogen or halogen bonds, their behaviour within the crystal packing was also of interest. The experiments yielded five crystal structures, namely 2-aminopyridin-1-ium 2-amino-6-chloro-4-oxo-4 H-pyrimidin-3-ide-2-amino-6-chloropyrimidin-4(3 H)-one (1/3), C5H7N2+·C4H3ClN3O−·3C4H4ClN3O, (I a), 2-aminopyridin-1-ium 2-amino-6-chloro-4-oxo-4 H-pyrimidin-3-ide-2-amino-6-chloropyrimidin-4(3 H)-one-2-aminopyridine (2/10/1), 2C5H7N2+·2C4H3ClN3O−·10C4H4ClN3O·C5H6N2, (I b), the solvent-free cocrystal 2-amino-5-bromo-6-methylpyrimidin-4(3 H)-one-2-amino-5-bromo-6-methylpyrimidin-4(1 H)-one (1/1), C5H6BrN3O·C5H6BrN3O, (II), the solvate 2-amino-5-bromo-6-methylpyrimidin-4(3 H)-one-2-amino-5-bromo-6-methylpyrimidin-4(1 H)-one- N-methylpyrrolidin-2-one (1/1/1), C5H6BrN3O·C5H6BrN3O·C5H9NO, (III), and the partial cocrystal 2-amino-5-bromo-6-methylpyrimidin-4(3 H)-one-2-amino-5-bromo-6-methylpyrimidin-4(1 H)-one-2-amino-6-chloropyrimidin-4(3 H)-one (0.635/1/0.365), C5H6BrN3O·C5H6BrN3O·C4H4ClN3O, (IV). All five structures show R22(8) hydrogen-bond-based patterns, either by synthon 2 or by synthon 3, which are related to the Watson-Crick base pairs. [ABSTRACT FROM AUTHOR]

Background Primary thyroid lymphoma (PTL) is uncommon, accounting for 2% to 5% of all thyroid malignancies. Papillary thyroid carcinoma (PTC) is the most frequent thyroid cancer. The coexistence of PTL and PTC is very rare, and the preoperative diagnosis is rather difficult. Methods A 41-year-old male patient complaining of fast painless thyroid enlargement for 2 months and a cervical mass for half a month was presented. Imaging demonstrated an enlarged thyroid and a mass in the thyroid. Results Surgery was conducted, and the final diagnosis of coexistence of PTL and PTC was confirmed by histopathological and immunohistochemical examination. The patient was then treated with cyclophosphamide, hydroxy doxorubicin, oncovin, prednisone (CHOP) chemotherapy and radiotherapy. After 2 months of follow-up, no recurrence or metastasis was noted. Conclusion This rare case highlights the importance for physicians to keep PTL in mind for differential diagnosis in patients with sudden thyroid enlargement and who have clinical history of Hashimoto thyroiditis. © 2015 Wiley Periodicals, Inc. Head Neck 37: E109-E114, 2015 [ABSTRACT FROM AUTHOR]

Novel,water-soluble CdTe quantum dots (QDs) capped with β-cyclodextrin (β-CD) and ~ 4.0 nm in diameter were synthesized in aqueous solution, and characterized using transmission electron microscopy (TEM). A fluorescence-sensing system based on the photoinduced electron transfer (PET) of (mono-6-thio-β-CD)-CdTe QDs was then designed to measure the interaction of phenothiazine dyes [methylene blue (MB) and methylene green (MG)]with herring sperm DNA (hsDNA). This fluorescence-sensing system was based on a fluorescence "OFF-ON" mode. First,MB/MG adsorbed on the surface of (mono-6-thio-β-CD)-CdTe QDs effectively quenches the fluorescence of (mono-6-thio-β-CD)-CdTe QDs through PET. Then, addition of hsDNA restores the fluorescence intensity of (mono-6-thio-β-CD)-CdTe QDs, because hsDNA can bind with MB/MG and remove it from the as prepared (mono-6-thio-β-CD)-CdTe QDs. In addition, detailed reaction mechanisms of the (mono-6-thio-β-CD)-CdTe QDs-MB/ MG-hsDNA solution system were studied using optical methods, by comparison with the TGA-CdTe QDs-MB/MG-hsDNA solution system. [ABSTRACT FROM AUTHOR]

Pomegranate ( Punica granatum L.) juice (PJ) contains different types of antioxidants and bioactive polyphenols and has been reported to promote cardiovascular health through several mechanisms. The present study aimed to examine the effects of 2-week intake of fresh PJ on blood pressure, flow-mediated dilatation (FMD), serum lipid profile and concentrations of inflammatory and endothelial function biomarkers. Twenty-one hypertensive patients (aged 30-67 years) were recruited into the trial and assigned to receive either PJ (150 ml/day in a single occasion between lunch and dinner; n = 11) or the same amount of water ( n = 10) for a period of 2 weeks. Systolic (SBP) and diastolic (DBP) pressures together with FMD and serum concentrations of lipid profile parameters, apolipoproteins A and B, intracellular adhesion molecule-1 (ICAM-1), vascular endothelial adhesion molecule 1 (VCAM-1), E-selectin, high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) were measured at baseline and at the end of trial. PJ consumption was associated with significant reductions in SBP ( p = 0.002) and DBP ( p = 0.038) but not FMD ( p > 0.05). Serum levels of VCAM-1 ( p = 0.008) were significantly reduced by PJ while those of E-selectin were elevated ( p = 0.039). However, no significant effect was observed from PJ on serum levels of ICAM-1, hs-CRP, lipid profile parameters, apolipoproteins and IL-6 in any of the study groups ( p > 0.05). Consumption of PJ for 2 weeks has effective hypotensive effects, and may improve endothelial function by decreasing serum concentrations of VCAM-1. These findings suggest PJ as a beneficial cardioprotective supplement for hypertensive subjects. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Context Recent reviews have claimed that the script concordance test ( SCT) methodology generally produces reliable and valid assessments of clinical reasoning and that the SCT may soon be suitable for high-stakes testing. Objectives This study is intended to describe three major threats to the validity of the SCT not yet considered in prior research and to illustrate the severity of these threats. Methods We conducted a review of SCT reports available through the Web of Science database. Additionally, we reanalysed scores from a previously published SCT administration to explore issues related to standard SCT scoring practice. Results Firstly, the predominant method for aggregate and partial credit scoring of SCTs introduces logical inconsistencies in the scoring key. Secondly, our literature review shows that SCT reliability studies have generally ignored inter-panel, inter-panellist and test-retest measurement error. Instead, studies have focused on observed levels of coefficient alpha, which is neither an informative index of internal structure nor a comprehensive index of reliability for SCT scores. As such, claims that SCT scores show acceptable reliability are premature. Finally, SCT criteria for item inclusion, in concert with a statistical artefact of the SCT format, cause anchors at the extremes of the scale to have less expected credit than anchors near or at the midpoint. Consequently, SCT scores are likely to reflect construct-irrelevant differences in examinees' response styles. This makes the test susceptible to bias against candidates who endorse extreme scale anchors more readily; it also makes two construct-irrelevant test taking strategies extremely effective. In our reanalysis, we found that examinees could drastically increase their scores by never endorsing extreme scale points. Furthermore, examinees who simply endorsed the scale midpoint for every item would still have outperformed most examinees who used the scale as it is intended. Conclusions Given the severity of these threats, we conclude that aggregate scoring of SCTs cannot be recommended. Recommendations for revisions of SCT methodology are discussed. [ABSTRACT FROM AUTHOR]

Traditional displays of principal component analyses lack readability to discriminate between putative clusters of variables or cases. Here, the author proposes a method that clusterizes and visualizes variables or cases through principal component analyses thus facilitating their analysis. The method displays pre-determined clusters of variables or cases as urchins that each has a soma (the average point) and spines (the individual variables or cases). Through three examples in the field of neuropsychology, the author illustrates how urchins help examine the modularity of cognitive tasks on the one hand and identify groups of healthy versus brain-damaged participants on the other hand. Some of the data used in this article were obtained from the Alzheimer's Disease Neuroimaging Initiative database. The urchin method was implemented in MATLAB, and the source code is available in the Supporting information. Urchins can be useful in biomedical studies to identify distinct phenomena at first glance, each having several measures (clusters of variables) or distinct groups of participants (clusters of cases). Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Writer's blocks: The first synthesis of RNA purine building blocks, 4′‐selenoadenosine and 4′‐selenoguanosine was achieved from D‐ribose by regioisomeric rearrangement, which was confirmed by X‐ray crystallography. 4′‐Selenoadenosine exists in an unusual mixture of north and south conformers in the solid state. [ABSTRACT FROM AUTHOR]

We aimed to study the effects of gingko biloba extract (EGb) on oxidative stress, astrocyte maturation and cognitive disfunction in offspring of hyperhomocysteinemic rats. Hyperhomocysteinemia was induced in the pregnant rats by administration of methionine (1 gr/kg body weight) dissolved in drinking water throughout pregnancy. One group of animals has received same amount of methionine plus 100 mg/kg/day EGb during pregnancy. On the postnatal day 1, half of the pups from all groups were sacrificed to study the lipid peroxidation (LPO) in different subfractions of brain. Other half of pups were tested in Morris water maze to assess differences in learning and memory performance at the 75 days of age. Maternal hyperhomocysteinemia significantly increased LPO levels especially in mitochondrial subfraction of fetal pup brains. EGb significantly prevented this LPO inrease. Methionine administration to animals reduced glial fibrillary acidic protein (GFAP) expression in pup brains significantly. EGb administration improved GFAP expression significantly. Offspring of hyperhomocysteinemic animals had poor long term spatial memory performance on Morris water maze and EGb administration had no effect on impaired spatial memory. In conclusion, maternally induced hyperhomocysteinemia significantly increased oxidative stress, decreased expression of GFAP and impaired learning performance. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]