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The characteristics of phase scintillation (represented by the phase scintillation indices, σφ) from GPS and Beidou are statistically analyzed using a ground‐based receiver at Zhongshan Station, Antarctica, from 2020 to 2022 for the first time. The phase scintillation of the GPS and Beidou signals present a similar pattern of occurrence. The statistical results on the occurrence morphology of phase scintillation show that the phase scintillation predominately occurs in the magnetic pre‐noon and pre‐midnight sectors. Moreover, phase scintillation performs a dependence on solar and geomagnetic activities. Furthermore, the phase scintillation also gives a seasonal variation with the maximum occurrence happened at the autumn and the minimum occurrence during the summer. Consequently, these results improve understanding of the morphological characteristics of the phase fluctuations in the less studied Antarctic region. The study also demonstrates the use of the combined data set to improve the coverage in the Antarctic region. Key Points: Morphological characteristics of phase scintillation of GPS and Beidou signals at Zhongshan station, Antarctica, for the first timeThe occurrences of phase scintillation mainly concentrated in the prenoon and pre‐midnight sectors for both signalsThe similar behaviors of phase scintillation convey the usefulness of the combined data for irregularity studies in the polar region [ABSTRACT FROM AUTHOR]

This paper investigates the formation and segmentation of the tongue of ionization into two consecutive polar cap patches using multi‐instrument observations from 27 February 2014. We provide insights into how the interplanetary magnetic field (IMF) variations influence the formation and segmentation of these patches. Our findings reveal that the entry of dayside dense plasma into the polar cap is predominantly driven by the modified convection near the cusp region, which is controlled by the transition of IMF By or the sudden drop of IMF Bz. Furthermore, we observe a rapid north‐westward plasma flow within the patch segmentation region, accompanied by equatorward‐expanded and enhanced convection near the cusp region. This fast‐moving flow, approximately 1.5 km/s, is characterized by low density and high electron temperature and shows a signature of a Subauroral Polarization Stream. This suggests that the fast‐westward flow, in conjunction with the expansion and contraction of ionospheric convection, plays a crucial role in the segmentation of polar cap patches from the dayside plasma reservoir. This study provides a comprehensive observation of the evolution of polar cap patches, thereby advancing our understanding of the dynamic mechanisms governing patch formation and segmentation. Plain Language Summary: Polar cap patches are highly dense structures in the polar cap region, typically forming in the cusp region and moving toward the nightside due to ionospheric convections. To better understand the factors that govern the formation and segmentation of these patches, a combination of satellite and ground‐based observations is used to investigate two consecutive polar cap patches on 27 February 2014. We found that the configuration of IMF By and Bz significantly influences cusp region convection, causing dayside sunlit dense plasma to enter the polar cap when cusp convection expands equatorward and the flow shifts northward, a process that leads to patch formation. Additionally, we observe strong north‐westward flows of low‐density, high‐electron‐temperature plasma in the subauroral region during periods of geomagnetic disturbance, displaying characteristics of Subauroral Polarization Streams (SAPS). This flow is observed in the patch segmentation region along with the equatorward‐expanding, enhanced cusp convection. These observations indicate that SAPS, along with the expansion and contraction of ionospheric convection, play a key role in the segmentation of polar cap patches from their equatorward plasma reservoir. This study significantly advances our understanding of the dynamic mechanisms governing the formation and segmentation of polar cap patches. Key Points: The transient change of IMF By and Bz leads to the formation of the tongue of ionization and segmentation of polar cap patchesA tongue of ionization is segmented into two polar cap patches by low electron density, high electron temperature, fast westward flowsThe expansion/contraction of the ionospheric convection also plays a crucial role in the segmentation of dayside dense plasma [ABSTRACT FROM AUTHOR]

The morphology and motion of auroras have been widely studied due to their indications on magnetospheric processes. Here, we report a new kind of "auroral curls," which have wavelengths in the mesoscale (∼100 km) and propagate azimuthally. Utilizing data from the Chinese Antarctic Zhongshan Station (the all‐sky imager and the high‐frequency radar), the Active Magnetosphere and Planetary Electrodynamics Response Experiment and the Defense Meteorological Satellite Program, we analyze an event occurred on 23 April 2019. We find these curls are fine structures in the poleward boundary of multiple arcs. Corresponding field‐aligned currents manifest as a series of longitudinally arranged pairs, while ionospheric flow velocities nearby oscillate with periods in the Pc 5 band. Observational evidence suggests these curls are connected with ultra‐low frequency (ULF) waves, which opens the possibility of using auroras to globally image ULF waves. Plain Language Summary: Auroras caused by precipitation of magnetospheric particles contain information about physical processes happened in the magnetosphere. In this letter, we report a new kind of auroral dynamic forms observed in Antarctica. These structures present both spatial and temporal periodic characteristics, which have similar scales with those of magnetospheric ultra‐low frequency (ULF) waves. We propose these auroral forms are connected with ULF waves, which provides a potential method to globally image ULF waves by analyzing properties of these auroras. Key Points: Azimuthally propagating "auroral curls" with mesoscale wavelengths were observed in AntarcticaThese curls are fine structures in the poleward boundary of multiple arcs formed by longitudinal‐arranged field‐aligned current pairsIonospheric flow velocities nearby oscillate with periods in the Pc 5 band, indicating connections with ultra‐low frequency waves [ABSTRACT FROM AUTHOR]

Pc1 geomagnetic pulsations within the frequency range of 0.2–5 Hz, the ground signatures of electromagnetic ion cyclotron (EMIC) waves, are usually observed to progress westward. A plausible explanation is that their westward‐excursion speed is defined by the drift velocity of the source particles in the geomagnetic dipole field. In this study, this relationship is examined through conjugate observations from ground‐based and spaceborne instruments. The ground‐based observations, including Pc1 pulsations and auroral emissions, consistently demonstrate a westward‐excursion speed of ∼4–5 MLT per hour, which agrees with the time delay between EMIC wave observations at two equatorial spacecraft. Observations of the wave source particles, however, indicate an inconsistency between the slow westward excursion speed and the high energy of the wave source protons. This apparent inconsistency is reconciled by the trapping motion of energetic particles within magnetic dips, which is supported by the simultaneous flux enhancements of protons across a broad energy range between ∼50 and ∼100 keV. These results improve our understanding of the westward excursion of Pc1 pulsations, and also underscore the need for caution when directly linking their westward‐excursion speed to the energies of the source particles. Plain Language Summary: Ground‐based magnetometers often observe geomagnetic field oscillations at various frequencies, among which are Pc1 pulsations within the frequency range of 0.2–5 Hz. It is commonly believed that these pulsations correspond to electromagnetic ion cyclotron (EMIC) waves in Earth's magnetosphere, which are excited by anisotropic distributions of energetic ions. The Pc1/EMIC waves are usually observed to progress westward, and the excursion speed is thought to be determined by the drift velocity of source ions in the geomagnetic dipole field. This relationship is examined in this study based on multi‐point observations of ground‐based magnetic pulsations, auroral emissions, EMIC waves near the equatorial magnetosphere, and energetic particles in space. Ground‐based magnetometers show the westward excursion of Pc1 pulsations at a speed of ∼4–5 magnetic local time per hour, consistent with proton auroral emissions and equatorial spacecraft observations. However, this speed does not match the drift speed of observed source protons in the geomagnetic dipole field. We suggest that this apparent inconsistency can be reconciled after considering the revision of particles' drift motion in the presence of concomitant, localized field depressions in the magnetosphere. This explanation, supported by spacecraft observations, sheds new light on the intricate interactions between geomagnetic disturbances and the behavior of energetic particles. Key Points: We observe the westward excursion of ground Pc1 pulsations at ∼4–5 MLT/hr, consistent with auroral and multi‐spacecraft observationsThe excursion speed appears to be lower than the drift speed of the anisotropic source protons in the unperturbed geomagnetic fieldThe apparent inconsistency can be reconciled after considering the trapped motion of particles in localized magnetic dips [ABSTRACT FROM AUTHOR]

Inorganic‐organic hybrid materials are a kind of multiduty materials with high crystallinity and definite structures, built from functional inorganic and organic components with highly tunable photochemical properties. Perylenediimides (PDIs) are a kind of strong visible light‐absorbing organic dyes with π‐electron‐deficient planes and photochemical properties depending on their micro‐environment, which provides a platform for designing tunable and efficient hybrid photocatalytic materials. Herein, four radical‐doped PDI‐based crystalline hybrid materials, Cl4‐PDI⋅SiW12O40 (1), Cl4‐PDI⋅SiMo12O40 (2), Cl4‐PDI⋅PW12O40 (3), and Cl4‐PDI⋅PMo12O40 (4), were attained by slow diffusion of polyoxometalates (POMs) into acidified Cl4‐PDI solutions. The obtained PDI‐based crystalline hybrid materials not only exhibited prominent photochromism, but also possessed reactive organic radicals under ambient conditions. Furthermore, all hybrid materials could be easily photoreduced to their radical anions (Cl4‐PDI⋅−), and then underwent a second photoexcitation to form energetic excited state radical anions (Cl4‐PDI⋅−*). However, experiments and theoretical calculations demonstrated that the formed energetic Cl4‐PDI⋅−* showed unusual POM‐dependent photocatalytic efficiencies toward the oxidative coupling of amines and the iodoperfluoroalkylation of alkenes; higher photocatalytic efficiencies were found for hybrid materials 1 (anion: SiW12O404−) and 2 (anion: SiMo12O404−) compared to 3 (anion: PW12O403−) and 4 (anion: PMo12O403−). The photocatalytic efficiencies of these hybrid materials are mainly controlled by the energy differences between the SOMO‐2 level of Cl4‐PDI⋅−* and the LUMO level of the POMs. The structure‐photocatalytic activity relationships established in present work provide new research directions to both the photocatalysis and hybrid material fields, and will promote the integration of these areas to explore new materials with interesting properties. [ABSTRACT FROM AUTHOR]

Dayside magnetosphere interactions are essential for energy and momentum transport between the solar wind and the magnetosphere. In this study, we investigate a new phenomenon within this regime. Sudden enhancements of ion fluxes followed by repeating dropouts and recoveries were observed by Magnetospheric Multiscale on 5 November 2016, which is the very end of the recovery phase from a moderate geomagnetic storm. These repetitive flux variations display energy‐dispersive characteristics with periods relevant to ion bounce motion, suggesting they are corresponding echoes. Alongside the flux variations, bipolar electric field impulses originating from external sources were detected. We traced the source region of the initial injection and found it is located near the spacecraft's position. To elucidate the underlying physics, a test‐particle simulation is conducted. The results reveal that radial transport resulting from impulse‐induced acceleration can give rise to these echoes. Observations demonstrate dayside magnetosphere interactions are more common than we previously considered, which warrants further research. Plain Language Summary: In spacecraft observations, the quasi‐periodical motion of particles in the geomagnetic field can generate repeating signals known as "echoes". Examining the relationship between the periods of echoes and the particle's energy is necessary for determining their types. The present study reports a novel mechanism responsible for generating echoes that arise from the ion bounce motion along magnetic field lines. Observations from both ground‐based stations and spacecraft, as well as numerical simulations, suggest these echoes can result from the acceleration and radial diffusion of ions responding to external field variations. These findings extend the current understanding of interactions in the dayside outer magnetosphere. Key Points: Ion acceleration and corresponding bounce echoes were observed by MMS in the dayside outer magnetosphereObservations and simulations suggest these echoes are driven by the accompanied electric field impulsesImpulse‐induced ion radial transport with positive phase space density radial gradient leads to the observed pattern [ABSTRACT FROM AUTHOR]

Stimulus‐responsive molecular photochromic materials have potential applications in sensor, information storage, and optical switch devices since they undergo reversible color changes upon stimulus from external light. In this work, a viologen‐derived Mg(II) coordination complex with molecular formula [Mg(dpbp)2(H2O)4] (1) has been synthesized from 1‐(3,5‐dicarboxyphenyl)‐4,4′‐bipyridinium chloride (H2dpbp⋅Cl) under solvothermal conditions. Complex 1 has a three‐dimensional viologen‐based hydrogen bond network showing reversible photochromism through radical formation under ultraviolet‐visible light irradiation. Simultaneously, the emission of complex 1 can be reversibly modulated by ultraviolet‐visible light irradiation. Importantly, due to its reversible photochromic properties, practical fading time, and high stability, complex 1 can be used as an ink‐free and erasable printing medium by applying ultraviolet visible light irradiation with a mask. [ABSTRACT FROM AUTHOR]

Asymmetry is a prevalent characteristic in numerous space physics phenomena. In this study, we investigate the statistical properties and spatial variations of ultra‐low frequency power globally after positive dynamic pressure pulses, utilizing high‐resolution magnetic field data from SuperMAG between 2012 and 2019. Specifically, we focus on the dawn‐dusk and north‐south asymmetries of Pc2‐5 fluctuations. Our analysis reveals that the power enhancement in the Pc2 band at approximately 30° magnetic latitude (MLAT) in the southern hemisphere is attributable to the South Atlantic Anomaly region. At MLAT ≈ 15°, the power of Pc3‐5 waves in both hemispheres exhibits a local minimum, which is associated with the strong coupling of compressional and Alfvén waves. Moreover, around MLAT = 60°, the dawnside Pc5 wave power exceeds that on the duskside when the interplanetary magnetic field (IMF) is westward, and the result is reversed when the IMF is eastward. Notably, Pc3‐5 wave power from MLAT = 30° to MLAT = 75° in the northern hemisphere is generally higher than that in the southern hemisphere. In regions with MLAT > 75°, which corresponds to the polar cap between 0 and 15 magnetic local time, the power of Pc3 pulsations is higher during summer in the northern hemisphere and higher during winter in the southern hemisphere. These findings underscore the significant role of the solar wind and the IMF in controlling geomagnetic pulsations and further deepen our understanding of the coupling between fluctuations in the ionosphere and the magnetosphere. Key Points: Pc3‐5 ultra‐low frequency wave power exhibits a local minimum at magnetic latitude (MLAT) of 15°At 60°N MLAT, the dawn‐dusk asymmetry of the Pc5 power is controlled by the sign of interplanetary magnetic field ByBetween 30° and 75° MLAT, the northern hemisphere has stronger Pc3‐5 wave power [ABSTRACT FROM AUTHOR]

Solar wind dynamic pressure pulse is one of the sources of ultra‐low frequency (ULF) waves. Based on 1‐second resolution magnetic field observations from SuperMAG from 2012 to 2019, we conducted a statistical study on temporal and spatial variations of global ULF power after the arrival of positive dynamic pressure pulses. The magnetosphere responds quickly to the dynamic pressure pulse within 1 min. At low L‐shells, it takes 4–6 min for the ULF waves to reach a power maximum, then ULF waves decay on a timescale of about 10 min. The spatial distribution of ULF wave power is closely related to the direction of the interplanetary magnetic field (IMF) when the dynamic pressure pulse arrives. The southward IMF leads to the reconnection on the dayside and more intense substorm activities on the nightside, accompanied by stronger ULF wave power globally. The power enhancement in the Pc2 band exhibits a notable fluctuation concentrated primarily in the range of L = 7 to 9, compared with the quiet period. In contrast, the amplification of Pc3 wave power occurs predominantly at higher L‐shells. However, the fluctuation of Pc5 power exhibits an opposite pattern, indicating disparate excitation and propagation mechanisms. In addition, seasonal effects affect the ULF power in different bands, which can be explained by the Russell‐McPherron (R‐M) effect. Our statistical results on long‐term, global‐scale geomagnetic observations illustrate that pressure pulses are important sources of ULF waves, and the spatial distribution of wave power varies greatly under different solar wind conditions. Key Points: SuperMAG ultra‐low frequency (ULF) parameters are used to study the spatial and temporal responses of ULF waves to pressure impulsesThe ULF power has great differences in the distribution as a function of magnetic local time and L‐shellSeasonal effects have significant influences on the magnetic field power in different bands [ABSTRACT FROM AUTHOR]

Poleward‐moving auroral arcs (PMAAs) with recurrence periods on the order of minutes have been established as a distinct form of auroral activities. Their origin and characteristics, especially those on the dayside, are less understood due to the paucity of observations. Here, we investigate a periodic PMAA event at the postdawn sector based on optical measurements from the high‐latitude Yellow River Station and magnetic measurements from multiple ground‐based stations. The optical observations demonstrate a long duration (∼2.5 hr) of the periodic auroral arcs at not only the well‐established red‐line but also the green‐ and the blue‐lines. This multi‐band feature, together with images at far‐ultraviolet wavelengths, demonstrates a wide energy range of precipitating electrons from hundreds of eV to several keV, with a characteristic energy of ∼2 keV. The auroral luminosity variations at different wavebands show a consistent periodicity within 1.67–3 mHz, which is also shown in the ground‐based magnetic pulsations. The auroral arc and magnetic field observations display signatures of field line resonance, which are likely driven by perturbations at the magnetopause boundary layer. These results complement our knowledge of the dayside periodic PMAAs and improve our understanding of their relationship with ultra‐low frequency waves. Plain Language Summary: Aurora is one of the most important phenomena associated with magnetosphere‐ionosphere coupling. Auroral arcs, one of the most prominent auroral forms, are characterized by a narrow width in the north‐south direction but an elongated structure in the east‐west direction. The advanced ground‐based optical instrumentation has demonstrated a distinct type of auroral arcs, the poleward‐moving auroral arcs (PMAAs) with a recurrence period on the order of minutes. However, since stations at relatively‐low latitudes cannot provide optical observations at the dayside due to the sunlit interference, our understanding of periodic PMAAs on the dayside and their associated electron precipitation is very limited. Here, we utilize observations from the high‐latitude Yellow River Station to investigate a periodic PMAA event at the postdawn sector. The optical observations demonstrate the long‐duration characteristics and the multi‐wavelength feature of the periodic arcs. The variations of the auroral luminosity and the ground‐based magnetic field pulsations show consistent periodicity within the ultra‐low frequency (ULF) range, with the spatiotemporal characteristics displaying signatures of field line resonance. These observations provide a valuable opportunity for us to study the dayside periodic PMAAs and their relationship with ULF waves, indicating that the flank region could serve as an active source for periodic PMAAs. Key Points: Multi‐band auroral observations at postdawn sector indicate the successive appearance of poleward‐moving auroral arcs, lasting ∼2.5 hrAuroral intensity and geomagnetic field variations, with similar periodicity within 1.67–3 mHz, show characteristics of field line resonanceThe auroral intensity is strongly enhanced within a 20‐min interval, which is likely driven by localized perturbations in the magnetopause [ABSTRACT FROM AUTHOR]

Throat auroras and polar cap patches are common phenomena in the polar ionosphere resulting from magnetosphere‐ionosphere coupling. A campaign was organized, with all‐sky imagers at Yellow River Station, the European Incoherent Scatter Svalbard Radar, and coordinated low‐altitude spacecraft observations. During periods of radial interplanetary magnetic field (IMF), observations showed that, as poleward moving throat auroras faded around the polar cap boundary, they linked to poleward moving ionization patches. The throat auroras were produced by soft‐electron precipitation associated with dayside magnetic reconnection. The red line emission intensity of throat auroras was correlated with dayside reconnection events. Dense plasma from lower latitudes was transported poleward via enhanced convection in the throat auroras to form patches. This is a potentially new formation mechanism for patches associated with throat auroras and magnetic reconnection for radial IMF. Moreover, the patches move anti‐sunward due to the E × B drift. Plain Language Summary: The polar ionosphere is a key region in the solar wind‐magnetosphere‐ionosphere coupling processes. The throat auroras and polar cap patches are important phenomenon in the polar ionosphere, and are associated with magnetopause dynamic processes. To clarify the relationship between throat auroras and patches, we organized a campaign of multiple instruments observations of Yellow River Station all‐sky imagers, European Incoherent Scatter Svalbard Radar, and low‐altitude spacecraft observations. We found that the throat auroras and patches were closely linked as they move poleward. The throat auroras were produced by soft‐electron precipitation associated with dayside magnetic reconnection for radial interplanetary magnetic field (IMF). We proposed a potentially new formation mechanism for patches from throat auroras under IMF Bx‐dominant that high density plasma from lower latitudes was transported poleward via enhanced convection in the throat auroras to form patches. Moreover, the patches moved anti‐sunward due to the E × B plasma drift. Key Points: The formation of throat auroras and polar cap patches is studied with multiple instruments in space and on groundBoth throat auroras and polar cap patches are closely linked as they move polewardThe formation of throat auroras and patches is associated with magnetic reconnection for dominant radial interplanetary magnetic field [ABSTRACT FROM AUTHOR]

Solar flares can severely disturb the Earth's ionosphere, leading to changes of atmospheric chemistry and degradation of Global Navigation Satellite System (GNSS) signals. The key to better assess these effects is to more accurately quantify the electron density enhancements induced by solar flares, which is still uncertain. Thanks to the good coverage and quiet electromagnetic environment provided by the Great Wall Station (GWS, 62.22°S, 58.96°W) in Antarctica, our Very‐Low‐Frequency (VLF) receiver has recorded clean VLF signatures produced by three X‐class solar flares from March to May in 2022. These measurements motivate us to revisit the uncertain question related to the ionospheric effects induced by solar flares. Different from previous studies, we model solar flare events from satellite measurements of X‐ray fluxes to ground‐based measurements of VLF transmitter signals by combining a flare irradiance model, an X‐ray propagation model, a D‐region chemistry model, and a VLF propagation model. For eight transmitting frequencies and propagation paths, modeling results can satisfactorily explain our VLF measurements at GWS during the three X‐class flares, especially so for the X1.3 event occurring on 30 March 2022. Moreover, the electron density results that reconcile space‐ and ground‐based measurements suggest that the VLF reflection height can be lowered to ∼66 km by an X1.1 flare, in line with previous studies. The present set of numerical models can be thus utilized in future studies to improve the nowcasting capability of VLF sensing technique for monitoring solar flares, as well as the accuracy of GNSS navigation/positioning during solar flares. Plain Language Summary: The X‐ray fluxes emitted during solar flares can significantly influence the Earth's ionosphere, leading to delays of Global Navigation Satellite System signals and atmospheric chemistry changes. A Very‐Low‐Frequency (VLF, 3–30 kHz) receiver has been recently deployed at the Great Wall Station in Antarctica, a location with a good coverage of navy transmitters in the northern hemisphere and quiet electromagnetic environment. This receiver has recorded the VLF signatures of three X‐class solar flare events from late March to early May in 2022. In this study, we report these VLF measurements during X‐class solar flares in Antarctica, and model these events using four well‐validated models, including a flare irradiance model, an X‐ray propagation model, a D‐region chemistry model, and a VLF propagation model. For eight transmitting frequencies and VLF propagation paths, modeling results show good agreements with the VLF measurements during the three X‐class flare events, as well as previous studies. This set of numerical models, after being validated using Great Wall Station measurements, can be used in future studies to better quantify the influence of solar flare events on the Earth's ionosphere and radio wave propagation. Key Points: We report ground‐based measurements of Very‐Low‐Frequency (VLF) signals during X‐class solar flares at the Great Wall station in AntarcticaWe model the responses of VLF transmitter signals to solar flares based upon the combination of four well‐validated modelsModeling results are consistent with the VLF transmitter signal measurements for eight propagation paths during three X‐class flare events [ABSTRACT FROM AUTHOR]

A mechanism recently proposed for magnetospheric electron loss into the atmosphere is the precipitation directly driven by ultralow‐frequency (ULF) waves. In this study, we quantitatively analyze the properties of ULF wave‐induced precipitation by simulating the electron bounce and drift motion in poloidal‐mode waves excited in a dipole magnetic field. Our results reveal that precipitation occurs only when electrons encounter a westward‐directed wave electric field in the magnetosphere, which leads to cross‐field energy enhancements and reduces their mirror heights. The simulations also demonstrate longer duration electron precipitation at the drift‐resonance energy. We calculate the temporal variations of the energy spectrum for precipitating electrons and the total precipitating energy fluxes. These results improve our understanding of ULF wave‐induced electron precipitation as well as provide a point of comparison for observations from balloons or ground‐based instruments. Plain Language Summary: Electron precipitation into the atmosphere is a major mechanism for electron loss in the radiation belts. A critical driver for the precipitation is the pitch‐angle scattering induced by various plasma waves in the frequency range between several hertz and tens of kilohertz. On the other hand, ultralow‐frequency (ULF) waves on the order of several millihertz are usually believed to play an indirect role, by modulating other types of waves. Here, we investigate a recently proposed mechanism of electron precipitation directly driven by ULF waves, by simulating electron motion within a poloidal‐mode wave field. The simulations, which cover electron bounce and drift time scales, reveal the important role of the azimuthal wave electric field in the induced electron precipitation. The precipitation occurs when the electrons encounter a westward‐directed electric field, which accelerates the electrons and reduces their mirror heights. The induced precipitation also shows an energy dependence; electrons at the drift‐resonance energy, which encounter a sustained westward‐directed electric field, would have longer precipitation duration than non‐resonant electrons. We further calculate the energy spectrum and the total fluxes of the precipitating electrons directly driven by ULF waves, and demonstrate that the effect could be potentially comparable to that caused by other magnetospheric waves. Key Points: We investigate electron precipitation driven by poloidal‐mode ultralow‐frequency waves that perturb the electron dynamics over bounce and drift timescalesPrecipitation occurs when electrons encounter westward electric fields, which enhance their cross‐field energy and reduce the mirror heightsDrift‐resonant electrons can continuously encounter westward electric fields to have longer precipitation duration than non‐resonant ones [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine the relationship between telomere length (TL) in subcutaneous adipose tissue (SAT), visceral adipose tissues (VAT), and leukocytes, as well as to examine the associations of TL in these tissues with postsurgical weight loss in Asians with severe obesity.Methods: Presurgery TL was measured in leukocytes, SAT, and VAT of 91 patients who underwent weight loss surgery. Correlation between TL in multiple tissues was assessed using Pearson correlation. The association of presurgery TL and postsurgical weight loss at 6 or 12 months, expressed as a percentage of weight loss, was determined using linear regression in 70 patients.Results: Telomeres were longer in VAT compared with those in leukocytes and SAT (P < 0.001) but were highly correlated between tissues. The strongest correlation was observed between TL in VAT and leukocytes (r = 0.739, P = 6.22 × 10-17 ). Compared with individuals in the highest tertile, those in the lowest tertile of VAT TL showed greater weight loss (β = 6.23, SE = 3.10, P = 0.044) independent of age, sex, ethnicity, types of surgery, diabetes condition, preoperative BMI, and follow-up period.Conclusions: Among patients with severe obesity, TL in leukocytes and adipose tissue was highly correlated. However, there was variability in the association of TL in these tissues with weight loss after surgery. [ABSTRACT FROM AUTHOR]

Drift‐bounce resonance between ultralow frequency (ULF) waves and ions is essential for ion energization in the magnetosphere. Here, we present the first comprehensive study of drift‐bounce resonance in the dayside outer magnetosphere, where off‐equatorial magnetic field minima would strongly distort ions' bounce and drift motion. A generalized theory is proposed, in which the effects of off‐equatorial minima, time‐evolving fields and ion bounce motion are taken into account. In consequence of these effects, ion pitch angle distributions undergo dramatic changes. In the presence of off‐equatorial minima, the time‐of‐flight effect of ion bounce motion forms latitude‐dependent dispersions besides "paw‐track shaped" structures, while evolving wave fields cause time‐dependent phase shifts in "paw‐tracks." All the predicted signatures have been confirmed by 5 years of Magnetospheric Multiscale spacecraft data and numerical simulations. These results allow us to better understand the interactions between ULF waves and thermal ion species in global magnetospheric dynamics. Plain Language Summary: Ultralow frequency (ULF) waves are widely distributed magnetospheric waves that can efficiently accelerate particles and play important roles in geomagnetic activities. Various patterns of ULF wave‐particle interactions have been investigated in detail near the Earth. However, near the dayside boundary of the magnetosphere, the geomagnetic field changes slightly due to solar wind compression. Consequently, the interaction between ULF waves and particles is modified in this region. This study analyzes how the pattern of ULF wave‐particle interactions varies near the dayside boundary of the magnetosphere. We find the compression of the magnetic field, particle motion and ULF wave evolution change the observational signatures of ULF wave‐particle interactions in the region of interest. The results help us better understand the energy transport from the solar wind to the magnetosphere and the role of ULF waves in magnetospheric dynamics. Key Points: Ultralow frequency wave‐ion drift‐bounce resonance in the dayside outer magnetosphere is investigated with 5 years of Magnetospheric Multiscale observationsA generalized theory is proposed to explain the observed ion pitch angle evolutionThe effects of off‐equatorial minima and time‐evolving fields are taken into account successfully to depict the observations [ABSTRACT FROM AUTHOR]

The spatial distribution of aurora intensity is an important manifestation of solar wind‐magnetosphere‐ionosphere energy coupling process, and it oscillates with the change of space environment parameters and geomagnetic index. It is of great significance to establish an appropriate aurora intensity model for the prediction of space weather and the study of magnetosphere dynamics. Based on Ultraviolet Imager (UVI) data of Polar satellite, we constructed two auroral models by using two different neural networks, that is, the generalized regression neural network (GRNN), and the conditional generation adversarial network (CGAN). Input parameters of the models include interplanetary magnetic field, solar wind velocity and density, and the geomagnetic AE index. Output result is the spatial distribution of auroral intensity in altitude adjusted corrected geomagnetic (AACGM) coordinates. The structural similarity index (SSIM) of image quality is used as an evaluation standard of detail similarity between the prediction results of auroral intensity model and corresponding UVI images (complete similarity is 1, dissimilarity is 0, SSIM is generally considered to have good similarity if it is greater than 0.5). Based on the respective training datasets of GRNN and CGAN models, the evaluating results showed that the mean values (standard deviation) of SSIM were 0.5409 (0.0912) and 0.5876 (0.0712), respectively, so the prediction results from both models can restore the auroral intensity distribution of the original images of UVI. In addition, the value of SSIM can increase with the increase of the number of training data. Therefore, more training data will help improve the effectiveness of these models. Plain Language Summary: In the past decade, with the increase of space observation data, machine learning has been applied to space weather modeling, especially for the physical relationship is still not very clear modeling, machine learning and big data intervention can improve the applicability of the model. Although the research shows that some key parameters of space environment have a close and significant impact on aurora activity, the clear physical relationship between them is still a research problem for researchers. In this paper, the idea of directly using multiple space environment parameters to predict aurora excitation distribution is proposed, and two different aurora excitation models are established based on neural network. Moreover, these two modeling methods can be extended to other related space weather modeling. Key Points: Ultraviolet auroral intensity model driven by the interplanetary and geomagnetic parametersModeling based on different neutral network methodsStructural similarity index is used to evaluate model quality [ABSTRACT FROM AUTHOR]

Summary: Background: Leukocyte telomere length (LTL) is associated with obesity and obesity‐related traits, and there are ethnic‐specific determinants of LTL. Objective: To evaluate LTL associations with obesity and metabolic parameters in Asian children with early‐onset obesity. Methods: Genomic DNA was extracted from peripheral blood leukocytes of a cohort of children with (N = 371) and without obesity (N = 23), and LTL was measured using quantitative PCR (qPCR). Blood plasma was used for metabolic phenotyping. Statistical analysis was performed using SPSS and STATA. Results: Children with obesity had shorter LTL (coefficient = −0.683, PAdj = 1.24 × 10−3) as compared to children who were lean. LTL was found to be associated with waist circumference (coefficient = −0.326, PAdj = 0.044) and skin‐fold measures (coefficient between 0.267 and 0.301, PAdj between 4.27 × 10−4 and 7.06 × 10−7) in children with obesity. However, no significant associations were observed between LTL and metabolic parameters, and between LTL and inflammatory cytokines. LTL also did not significantly mediate the risk of non‐alcoholic fatty liver disease (NAFLD) in children with obesity. Conclusions: We showed for the first time that Asian children with severe obesity had shorter LTL, and the shortening of LTL was associated with other adiposity measures including waist circumference and skin‐fold measurements. [ABSTRACT FROM AUTHOR]

A photochemical C–N coupling of aryl halides with nitroarenes is demonstrated for the first time. Catalyzed by a NiII complex in the absence of any external photosensitizer, readily available nitroarenes undergo coupling with a variety of aryl halides, providing a step‐economic extension to the widely used Buchwald–Hartwig C–N coupling reaction. The method tolerates coupling partners with steric‐congestion and functional groups sensitive to bases and nucleophiles. Mechanistic studies suggest that the reaction proceeds via the addition of an aryl radical, generated from a NiI/NiIII cycle, to a nitrosoarene intermediate. [ABSTRACT FROM AUTHOR]

Throat auroras frequently observed near local noon have been confirmed to correspond to magnetopause indentations, but the generation mechanisms for these indentations and the detailed properties of throat aurora are both not fully understood. Using all‐sky camera and magnetometer observations, we reported some new observational features of throat aurora as follows. (1) Throat auroras can occur under stable solar wind conditions and cause clear geomagnetic responses. (2) These geomagnetic responses can be simultaneously observed at conjugate geomagnetic meridian chains in the Northern and Southern Hemispheres. (3) The initial geomagnetic responses of throat aurora show concurrent onsets that were observed at all stations along the meridians. (4) Immediately after the concurrent onsets, poleward moving signatures and micropositive bays were observed in the X components at higher‐ and lower‐latitude stations, respectively. We argue that these observations provide evidence for throat aurora being generated by low‐latitude magnetopause reconnection. We suggest that the concurrent onsets reflect the instantaneous responses of the reconnection signal arriving at the ionosphere, the followed poleward moving signatures reflect the antisunward dragging of the footprint of newly opened field lines, and the micropositive bays may result from a pair of field‐aligned currents generated during the reconnection. This study may shed new light on the geomagnetic transients observed at cusp latitude near magnetic local noon. Key Points: Interhemispheric conjugacy of throat aurora is examined by the associated geomagnetic responses under quiet solar wind conditionsConcurrent onsets followed by poleward moving signature are evidence supporting throat aurora being caused by magnetopause reconnectionX component increases observed after the concurrent onsets can be regarded as micropositive bays caused by a pair of field‐aligned currents [ABSTRACT FROM AUTHOR]

Throat auroras have been suggested to be related to indentations on the subsolar magnetopause. However, the indentation generation process and the resulting ionospheric responses have remained unknown. An EISCAT Svalbard Radar experiment was designed to run with all‐sky cameras, which enabled us for the first time to observe the temporal and spatial evolution of flow reversals, Joule heating, and ion upflows associated with throat aurora. The high‐resolution data enabled us to discriminate that the flow bursts and Joule heating were concurrent and co‐located, but were always observed on the west side of the associated throat auroras, reflecting that the upward/downward field‐aligned currents associated with throat aurora are always to the east/west, respectively. These results are consistent with the geometry of Southwood (1987) flux transfer event model and provide strong evidence for throat aurora being associated with magnetopause reconnection events. The results also support a conceptual model of the throat aurora. Key Points: An EISCAT radar experiment was designed to investigate the ionospheric characteristics of throat auroraMesoscale twin flow cells, Joule heating effects, and ion upflows were associated with the throat auroraThe observations support the idea that throat auroras are associated with magnetopause reconnection [ABSTRACT FROM AUTHOR]

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2,4,6‐Tris(pyridin‐4‐yl)‐1,3,5‐triazine (tpt), as an organic molecule with an electron‐deficient nature, has attracted considerable interest because of its photoinduced electron transfer from neutral organic molecules to form stable anionic radicals. This makes it an excellent candidate as an organic linker in the construction of photochromic complexes. Such a photochromic three‐dimensional (3D) metal–organic framework (MOF) has been prepared using this ligand. Crystallization of tpt with Cd(NO3)2·4H2O in an N,N‐dimethylacetamide–methanol mixed‐solvent system under solvothermal conditions afforded the 3D MOF poly[[bis(nitrato‐κ2O,O′)cadmium(II)]‐μ3‐2,4,6‐tris(pyridin‐4‐yl)‐1,3,5‐triazine‐κ3N2:N4:N6], [Cd(NO3)2(C18H12N6)]n, which was characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis and single‐crystal X‐ray diffraction. The X‐ray diffraction crystal structure analysis reveals that the asymmetric unit contains one independent CdII cation, one tpt ligand and two coordinated NO3− anions. The CdII cations are connected by tpt ligands to generate a 3D framework. The single framework leaves voids that are filled by mutual interpenetration of three independent equivalent frameworks in a fourfold interpenetrating architecture. The compound shows a good thermal stability and exhibits a reversible photochromic behaviour, which may originate from the photoinduced electron‐transfer generation of radicals in the tpt ligand. A fourfold interpenetrating cadmium(II) metal–organic framework, which has been prepared using the 2,4,6‐tris(pyridin‐4‐yl)‐1,3,5‐triazine ligand, exhibits prominent photochromic behaviour upon UV–Vis light irradiation. [ABSTRACT FROM AUTHOR]

Naphthalenediimides, a class of organic dyes with an expanded π-electron-deficient plane, have attracted considerable interest because of their photoinduced electron transfer from neutral organic moieties to stable anionic radicals. This makes them excellent candidates for organic linkers in the construction of photochromic coordination polymers. Such a photochromic two-dimensional coordination polymer has been prepared using N, N′-bis(pyridin-4-ylmethyl)naphthalene-1,8:4,5-bis(dicarboximide) (DPMNI). In crystallization tubes, upon slow diffusion of an MeOH solution of cadmium perchlorate into a CHCl3 solution of DPMNI, the complex poly[[bis[μ2-2,7-bis(pyridin-4-ylmethyl)benzo[ imn][3,8]phenanthroline-1,3,6,8(2 H,7 H)-tetrone-κ2 N: N′]bis(perchlorato-κ O)cadmium(II)] chloroform tetrasolvate], {[Cd(C26H16N4O4)2(ClO4)2]·4CHCl3} n, (I), was obtained. The asymmetric unit contains one Cd2+ cation, two DPMNI ligands, two coordinated ClO4− anions and four CHCl3 solvent molecules. Each Cd2+ cation is interconnected by four DPMNI linkers to generate a neutral two-dimensional naphthalenediimide coordination network with all the ClO4− anions above or below this plane. Strong interlaminar anion-π interactions between the coordinated ClO4− anions and the imide rings of an adjacent layer lead to a three-dimensional supramolecular structure. Compound (I) exhibits reversible photochromic behaviour and photocontrolled tunable luminescence properties, which may originate from the photoinduced electron-transfer generation of radicals in the DPMNI ligand. [ABSTRACT FROM AUTHOR]

The reaction of CdCl2·2.5H2O with 1,1'-bis(3-carboxybenzyl)-4,4'-bipyridinium dichloride (H2L1·Cl2) or 4,4'-bis[(3-carboxypyridino)methyl]-biphenyl dichloride (H2L2·Cl2) in a dimethylformamide/methanol mixed-solvent system at room temperature, affording the complexes [(CdCl2)3(L1)3]n (1) and {[CdCl2(L2)(H2O)2]· 2H2O}n (2). They were characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction. Both 1 and 2 exhibit 1D coordination networks, which further stack into a 3D supramolecular structure by hydrogen bonding and π-π interactions. Furthermore, these two complexes exhibit different photochromic behavior in the solid state, which may originate from different charge-distributions of H2L1·Cl2 and H2L2·Cl2 ligands. [ABSTRACT FROM AUTHOR]

Naphthalene diimides, which are planar, chemically robust and redox-active, are an attractive class of electron-deficient dyes, which can undergo a single reversible one-electron reduction to form stable radical anions in the presence of electron donors upon irradiation. This makes them excellent candidates for organic linkers in the construction of photochromic coordination polymers. Such a photochromic one-dimensional linear coordination polymer has been prepared using N, N′-bis(3-carboxyphenyl)naphthalene-1,8:4,5-tetracarboximide (H2BBNDI). Crystallization of H2BBNDI with magnesium nitrate in an N, N′-dimethylformamide (DMF)/ethanol/H2O mixed-solvent system under solvothermal conditions afforded the one-dimensional coordination polymer catena-poly[[bis(dimethylformamide-κ O)magnesium(II)]-bis[μ- N-(3-carboxylatophenyl)- N′-(3-carboxylphenyl)naphthalene-1,8:4,5-tetracarboximide-κ2 O: O′]], [Mg(C28H13N2O8)2(C3H7NO)2] n. The asymmetric unit contains half of a magnesium cation, one HBBNDI− ligand and one DMF molecule. Two partially deprotonated HBBNDI− ligands bridge two magnesium cations to form a one-dimensional chain. Strong inter-chain π-π interactions between the naphthalene rings of the HBBNDI− ligand and the imide rings of adjacent chains provide a two-dimensional structure. The supramolecular three-dimensional framework is stabilized by π-π interactions between naphthalene rings of neighbouring two-dimensional supramolecular networks. The complex exhibits a reversible photochromic behaviour, which may originate from the photoinduced electron-transfer generation of radicals in the HBBNDI− ligand. [ABSTRACT FROM AUTHOR]

The MnII-basedporousmetal-organicframework,[Mn3(btca)2-(HCOO)(μ3-OH)(H2O)2]·2DMF (1) (H2 btca = benzotriazole-5-carboxylate acid), was prepared by the solvothermal reaction of Mn(CH3COO)2·4H2O and H2btca, which was characterized by infrared spectroscopy, thermogravimetric analyses, and X-ray crystallographic study. 1 exhibits 3D framework with 1D rectangle channels constructed by the strip-shaped chains containing [Mn5(μ3-OH)2(btca)4]- pentaclusters subunits. Furthermore, the magnetic measures show that 1 exhibits weak ferromagnetic behavior at low temperature. [ABSTRACT FROM AUTHOR]

Aims Adverse drug reactions (ADRs) contribute to poorer patient outcomes and additional burden to the healthcare system. However, data on the true burden, relevant types and drugs causing ADRs are lacking. The aim of this study was to determine the prevalence of ADR-related hospitalization in the general adult population in Singapore and to investigate their characteristics. Methods We prospectively recruited 1000 adult patients with unplanned admission to a large tertiary-care hospital. Two independent reviewers evaluated all suspected ADRs for causality, type, severity and avoidability. The prevalence of ADR-related hospitalization was calculated based on 'definite' and 'probable' ADRs. Logistic regression was used to evaluate predictors for having an ADR at admission. Results The prevalence of all ADRs at admission was 12.4% (95% CI: 10.5-14.6%) and ADRs causing admission was 8.1% (95% CI: 6.5-10.0%). The most common ADRs were gastrointestinal-related. The most common drug category causing ADRs were cardiovascular drugs. Patients with ADRs had a longer length of stay than those who did not (median 4 vs. 3 days, P = 1.70 × 10−3). About 30% of ADRs at admission were caused by at least one drug with a clinical annotation in the Pharmacogenomics KnowledgeBase (PharmGKB), suggesting that some of these ADRs may have been predicted by pharmacogenetic testing. Conclusions We have quantified the burden and characteristics of clinically impactful ADRs in the Singaporean general adult population. Our results will provide vital information for efforts in reducing ADRs through targeted vigilance, patient education and pharmacogenomics in Singapore. [ABSTRACT FROM AUTHOR]

Thiosemicarbazides and their metal complexes have attracted considerable interest because of their biological activities and their flexibility, which allows the ligands to bend and rotate freely to accommodate the coordination geometries of various metal centres. Discrete copper(II) and cadmium(II) complexes have been prepared by crystallization of N-[2-(2-hydroxybenzoyl)hydrazinecarbonothioyl]propanamide (H3 L) with Cu(CH3COO)2 or Cd(NO3)2 in a dimethylformamide/methanol mixed-solvent system at room temperature, affording the complexes di-μ-acetato-bis{μ4-1-[(2-oxidophenyl)carbonyl]-2-(propanamidomethanethioyl)hydrazine-1,2-diido}tetracopper(II) dimethylformamide disolvate, [Cu4(C11H10N3O3S)2(C2H3O2)2]·2C3H7NO, (I), and bis{μ2-[(2-hydroxyphenyl)formamido](propanamidomethanethioyl)azanido}bis[(4,4′-bipyridine)nitratocadmium(II)] dihydrate, [Cd2(C11H12N3O3S)2(NO3)2(C10H8N2)2]·2H2O, (II). Complex (I) consists of four CuII cations, two μ4-bridging trianionic ligands and two μ2-bridging acetate ligands, while complex (II) is composed of two CdII cations, two μ2-bridging monoanionic ligands, two nitrate ligands and two 4,4′-bipyridine ligands. These discrete complexes are connected by hydrogen bonds and van der Waals interactions to form a three-dimensional supramolecular architecture. Compared with (I), the phenolic hydroxy group and hydrazide N atom of the thiosemicarbazide ligand of (II) are not involved in coordination and lead to a binuclear CdII complex. This different coordination mode may be attributed to the larger ionic radius of the CdII ion compared with the CuII ion. [ABSTRACT FROM AUTHOR]

A homochiral helical three-dimensional coordination polymer, poly[[(μ2-acetato-κ3 O, O′: O)(hydroxido-κ O)(μ4-5-nicotinamido-1 H-1,2,3,4-tetrazol-1-ido-κ5 N1, O: N2: N4: N5)(μ3-5-nicotinamido-1 H-1,2,3,4-tetrazol-1-ido-κ4 N1, O: N2: N4: N5)dicadmium(II)] 0.75-hydrate], {[Cd2(C7H5N6O)2(CH3COO)(OH)]·0.75H2O} n, was synthesized by the reaction of cadmium acetate, N-(1 H-tetrazol-5-yl)isonicotinamide (H-NTIA), ethanol and H2O under hydrothermal conditions. The asymmetric unit contains two crystallographically independent CdII cations, two deprotonated 5-nicotinamido-1 H-1,2,3,4-tetrazol-1-ide (NTIA−) ligands, one acetate anion, one hydroxide anion and three independent partially occupied water sites. The two CdII cations, with six-coordinated octahedral and seven-coordinated pentagonal bipyramidal geometries are located on general sites. The tetrazole group of one symmetry-independent NTIA− ligand links one of the independent CdII cations into 61 helical chains, while the other NTIA− ligand links the other independent CdII cations into similar but unequal 61 helical chains. These chains, with a pitch of 24.937 (5) Å, intertwine into a double-stranded helix. Each of the double-stranded 61 helices is further connected to six adjacent helical chains through an acetate μ2-O atom and the tetrazole group of the NTIA− ligand into a three-dimensional framework. The helical channel is occupied by the isonicotinamide groups of NTIA− ligands and two helices are connected to each other through the pyridine N and carbonyl O atoms of isonicotinamide groups. In addition, N-H...O and O-H...N hydrogen bonds exist in the complex. [ABSTRACT FROM AUTHOR]

The title coordination polymer, {[Cd2(CH2N5)(C6H4NO2)Cl(OH)]·0.14H2O} n, (I), was synthesized by the reaction of cadmium acetate and N-(1 H-tetrazol-5-yl)isonicotinamide in aqueous ammonia, using hydrochloric acid to adjust the pH. Under hydrothermal conditions, N-(1 H-tetrazol-5-yl)isonicotinamide slowly hydrolyzes to form isonicotinic acid (Hisonic) and 5-aminotetrazole (Hatz). The deprotonated form of isonicotinic acid (denoted isonic) acts as a bridging ligand in the structure. The polymer crystallizes in the monoclinic space group C2/ m. In the structure, there is one Cd3(μ3-OH) unit of C s symmetry, with one of the CdII atoms and the O and H atoms located on a mirror plane. The other crystallographically independent CdII cation is located on an inversion centre. Each edge of the Cd3(μ3-OH) isosceles triangle is bridged by an atz ligand in a μ1,2 or μ2,3/μ3,4 mode. The Cd3(μ3-OH) units are laced around with a belt of chloride ligands. The belts are further connected into undulating layers via weak inter-belt Cd-Cl bonds. The two organic ligands reside across mirror planes. The construction of a three-dimensional framework is completed by the pillaring isonic ligand. Water molecules partially occupy the voids of the framework. [ABSTRACT FROM AUTHOR]

Chronic stress causes a variety of psychiatric disorders such as anxiety and depression, but its mechanism is not well understood. Tripartite motif-containing protein 32 (TRIM32) was strongly associated with autism spectrum disorder, attention deficit hyperactivity disorder, anxiety and obsessive compulsive disorder based on a study of copy number variation, and deletion of TRIM32 increased neural proliferation and reduced apoptosis. Here, we propose that TRIM32 is involved in chronic stress-induced affective behaviors. Using a chronic unpredictable mild stress mouse depression model, we studied expression of TRIM32 in brain tissue samples and observed behavioral changes in Trim32 knockout mice. The results showed that TRIM32 protein but not its mRNA was significantly reduced in hippocampus in a time-dependent manner within 8 weeks of chronic stress. These stress-induced affective behaviors and reduction of TRIM32 protein expression were significantly reversed by antidepressant fluoxetine treatment. In addition, Trim32 knockout mice showed reduced anxiety and depressive behaviors and hyperactivities compared with Trim32 wild-type mice under normal and mild stress conditions. We conclude that TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. [ABSTRACT FROM AUTHOR]

The title complex, [Cu(C6H4N3)] n, was synthesized by the reaction of cupric nitrate, 1 H-benzotriazole (BTAH) and aqueous ammonia under hydrothermal conditions. The asymmetric unit contains three crystallographically independent CuI cations and two 1 H-benzotriazolate ligands. Two of the CuI cations, one with a linear two-coordinated geometry and one with a four-coordinated tetrahedral geometry, are located on sites with crystallographically imposed twofold symmetry. The third CuI cation, with a planar three-coordinated geometry, is on a general position. Two CuI cations are doubly bridged by two BTA− ligands to afford a noncentrosymmetric planar [Cu2(BTA)2] subunit, and two [Cu2(BTA)2] subunits are arranged in an antiparallel manner to form a centrosymmetric [Cu2(BTA)2]2 secondary building unit (SBU). The SBUs are connected in a crosswise manner via the sharing of four-coordinated CuI cations, Cu-N bonding and bridging by two-coordinate CuI cations, resulting in a one-dimensional chain along the c axis. These one-dimensional chains are further linked by C-H...π and weak van der Waals interactions to form a three-dimensional supramolecular architecture. [ABSTRACT FROM AUTHOR]

Abstract: DNA damage checkpoints are essential for maintenance of genome integrity. We report here that inducible overexpression of the transcription factor Sharp-1 results in an S and G2/M cell cycle arrest, concomitant with the upregulation of Brca1 and GADD45α expression. In addition, we show that endogenous Sharp-1 mRNA is increased by DNA-damaging agents. Consistently, Sharp-1 overexpressing cells exhibit reduced apoptosis in response to chemotherapeutic drugs along with lower p53 expression and activity. Our studies identify a novel function for Sharp-1 in cell cycle arrest and DNA damage-induced apoptosis. Inappropriate Sharp-1 expression may therefore be associated with tumorigenesis. [Copyright &y& Elsevier]

1. In the present study, we compared the elastin and collagen content of thoracic aortic medial and adventitial layers from Wistar-kyoto (WKY) and spontaneously hypertensive rats (SHR). In addition, the effects of losartan, an angiotensin II receptor antagonist, and spironolactone, a mineralocorticoid receptor antagonist, on collagen and elastin content were determined. 2. Prehypertensive (4-week-old) and hypertensive (16-week-old) SHR were randomly divided into three groups treated with either 0.9% NaCl, losartan (20 mg/kg per day) or spironolactone (200 mg/kg per day). Prehypertensive and hypertensive SHR were treated for 12 and 16 weeks, respectively. Age-matched WKY rats were not treated with NaCl, losartan or spironolactone and served as the control group. 3. The medial and adventitial layers of the thoracic aorta were composed mainly of elastin and collagen, respectively, in both SHR and WKY rats. Compared with WKY rats, SHR exhibited greater collagen and elastin content in the media, but decreased collagen and elastin content in the adventitial layer. Both medial and adventitial collagen and elastin content increased significantly with age in both strains and was greater in 32-week-old rats compared with 16-week-old rats. Spironolactone treatment decreased collagen content in the media of thoracic aortas from prehypertensive SHR, whereas losartan decreased collagen content in the media of aortas from hypertensive SHR. In contrast, neither spironolactone nor losartan had any effect on adventitial collagen content in prehypertensive and hypertensive SHR. Medial collagen and elastin were positively related to pulse pressure (PP), but there was no correlation between adventitial mass or collagen content and PP or mean arterial pressure in untreated and treated SHR and WKY rats. 4. In conclusion, the composition of the medial and adventitial layers of the thoracic aorta differs and treatment of SHR with losartan and spironolactone decreases collagen content when delivered at the hypertensive or prehypertensive stage, respectively. However, neither drug has any effect on adventitial collagen content in SHR. [ABSTRACT FROM AUTHOR]

The pleomorphic pathology of postmortem LRRK2-positive patients and the frequent association with late-onset Parkinson's disease (LOPD) symptoms suggest that LRRK2 mutations may play a role in Parkinson's Plus disorders and LOPD. Published studies primarily focus on the common G2019S mutation. Analysis of a spectrum of LRRK2 mutations in Parkinson's Plus disorders has yet to be reported. We investigated 14 leucine-rich repeat kinase 2 (LRRK2) mutations in a cohort of Parkinson's Plus disorders and LOPD. A total of 458 patients with progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal ganglionic degeneration (CBGD), atypical Parkinsonism (AP), and LOPD were screened for 14 mutations that span exons 19 to 41 of the LRRK2 gene. Among the LOPD cases, 1 patient was found to harbor the R1441C mutation. He presented with typical features of PD at age of 58 years old and responded well to levodopa. We did not detect any of the 14 mutations in PSP, MSA, CBGD, and AP patients. We highlight the first case of LRRK2 R1441C mutation in late onset sporadic PD of non-European ancestry. Furthermore, extensive mutational screen found LRRK2 mutations to be rare among patients who presented with PSP, MSA, CBGD, and AP. [ABSTRACT FROM AUTHOR]

Dietary sphingomyelin (SM) may have regulatory effects on cell proliferation and tumorigenesis in the colon. Alkaline sphingomyelinase (SMase) is the major enzyme responsible for hydrolysis of SM in the gut. Previously we purified the enzyme and showed that the presence of glycerophospholipids inhibited SM hydrolysis induced by alkaline SMase in vitro. In the present work, we studied the effects of TG, DG, FA, ceramide, and cholesterol on SM hydrolysis catalyzed by purified alkaline SMase. The results showed that both TG (triolein and tristearin) and DG (1,2-dioleoyl- sn-glycerol and 1,2-distearoyl- rac-glycerol) inhibited the activity of alkaline SMase. 1-Mono-oleoyl- rac-glycerol, 1-monostearoyl- rac-glycerol, stearic acid, oleic acid, linoleic acid, linolenic acid, and arachidonic acid stimulated the activity of alkaline SMase at 0.4–0.8 mM concentrations but inhibited the enzyme at higher concentrations. There was no difference between the effects induced by saturated and unsaturated FA. A short-chain FA such as lauric acid had a stronger stimulatory effect at low concentrations and weaker inhibitory effect at high concentrations than long-chain FA. Choosing linoleic acid as an example, we found that FA had similar effects on both alkaline SMase and neutral SMase. Cholesterol and ceramide when mixed with FA to increase its solubility in bile salt micelles inhibited SMase activity. In conclusion, glycerides, FA, ceramide, and cholesterol influence SM hydrolysis catalyzed by intestinal alkaline SMase. The presence of lipids in the diet may thus influence the course of SM digestion in the gut and thereby the exposure of colon to SM metabolites. [ABSTRACT FROM AUTHOR]

The title compound, [Cu8(C15H10N3O3S)4Cl4(C3H7NO)2]·2C3H7NO, consisting of eight CuII cations, four trianionic 1-(2-oxidobenzoyl)-2-(2-oxo-2-phenylethanethioyl)hydrazine-1,2-diide ligands, four chloride ligands and two coordinated and two solvent dimethylformamide molecules, crystallizes with the octanuclear molecule located on an inversion centre. The two halves of the molecule are connected by two bridging Cl atoms. This is the first example of an octanuclear complex based on a thiosemicarbazone-derived ligand. [ABSTRACT FROM AUTHOR]

We have designed and fabricated a terahertz multiband resonator based on TU-shaped metallic microstructure on polyimide substrate. The performance of the fabricated device was examined by using a terahertz time-domain spectroscopy system. The experimental results show three distinct resonant peaks at 0.37, 0.73 and 0.96 THz, which are in good agreement with the finite-difference time-domain (FDTD) simulation. The multiband resonators have great potential applications in the fields such as terahertz imaging and biosensors. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:857-859, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27457 [ABSTRACT FROM AUTHOR]

A common LRRK2 missense variant, Gly2385Arg, has been found to be a genetic risk factor for Parkinson's disease (PD) in ethnic Chinese and Japanese. However, the presence of the variant in other non-Chinese Asian patients has not been fully clarified. We performed genetic analysis of the Gly2385Arg variant in 472 non-Chinese Asian subjects in Singapore (comprising of 166 PD and 306 controls of Malay/Indian ethnicity). The frequency of the heterozygous Gly2385Arg genotype was not significantly different in PD compared with controls (1.2% vs. 0.8%, odds ratio = 2.83, 95% CI 0.40, 20.2, P = 0.3). No subjects carried the homozygous genotype. Stratification by Malay and Indian ethnicity revealed that there were two carriers each among 98 (2.0%) Malay PD and 173 (1.2%) Malay controls (odds ratio = 1.78, 95% CI 0.25, 12.8, P = 0.6), but there were no carriers among 66 Indian PD and 133 Indian controls. We demonstrated that the Gly2385Arg variant could be detected in our Malay subjects. However, its frequency was much lower than the 8 to 10% prevalence previously reported in our Singaporean and Taiwanese Chinese PD population. The relevance of Gly2385Arg as a genetic risk factor may be restricted to selected Asian races, and more studies will be needed to confirm our observations. [ABSTRACT FROM AUTHOR]

The G2019S mutation in the LRRK2 (leucine-rich repeat kinase) gene appears very rarely in the Chinese population. Among Chinese subjects who were non-G2019S carriers, we demonstrated the frequency of the LRRK2 G2019S founder haplotype (T-254-A-G-A-154) in Parkinson's disease and controls to be 33% and 30%. This rate is similar to the frequency in European noncarriers, indirectly supporting the association of this haplotype with G2019S carriers. The haplotype is likely to be more ancient than the G2019S mutation because it is also found in a population with a very low carrier rate. [ABSTRACT FROM AUTHOR]

The title compound, [Cu8(C15H10N3O3S)4Cl4(C3H7NO)2]·2C3H7NO, consisting of eight Cu(II) cations, four trianionic 1-(2-oxidobenzoyl)-2-(2-oxo-2-phenylethanethioyl)hydrazine-1,2-diide ligands, four chloride ligands and two coordinated and two solvent dimethylformamide molecules, crystallizes with the octanuclear molecule located on an inversion centre. The two halves of the molecule are connected by two bridging Cl atoms. This is the first example of an octanuclear complex based on a thiosemicarbazone-derived ligand.

ZNF804A, a recently identified risk gene for schizophrenia, has been extensively investigated and the principle finding for this locus has been the association with SNP rs1344706 in populations of European ancestries. However, in Asian populations, only a few studies have been conducted for rs1344706 and the results were inconsistent. Here, we studied rs1344706 and schizophrenia susceptibility in multiple Asian case-control samples (10 Chinese and 2 Japanese samples; N = 21,062), and the meta-analyses indicated non-significant association of rs1344706 with schizophrenia (P = 0.26), suggesting the same SNP identified in European samples is not predisposing risk in Asians. Further genotyping and association analyses of a set of SNPs spanning the entire genomic region of ZNF804A (520 kb) identified no association except for SNP rs359895 (P = 7.8 x 10(-5) , N = 5,172), a newly reported risk SNP located in the ZNF804A promoter region with functional implications. This suggests that ZNF804A may also contribute to schizophrenia susceptibility in Asians although the risk SNP is different from that in Europeans, and it was supported by the detected up-regulation of ZNF804A mRNA expression in the blood cells of Chinese schizophrenia patients compared with normal controls (P = 0.004). Additionally, the linkage disequilibrium (LD) structure analyses using data from HapMap indicated distinct LD blocks across ZNF804A between Chinese and Europeans, which may explain the different association patterns between them, and also highlight the compounding difficulty of genetic studies of complex diseases like schizophrenia when studying multiple ethnic populations., (2012 Wiley Periodicals, Inc)

Aims: Schizophrenia is a severe mental disorder with onset frequently in adolescence and followed by a chronic and disabling course. Although the exact pathophysiology of this devastating disorder has not been clearly elucidated, a large part of it has been attributed to genetic influences. This article seeks to provide an overview on what our group has embarked on--to elucidate genetic risk factors for schizophrenia within the Chinese ethnic group., Methods: We plan to conduct an integrated approach to interrogate comprehensively the genome from different angles and in stages. The first stage involves a genome-wide association study of 1000 cases of schizophrenia-control pairs, with a follow-up replication study in another 1000 cases of schizophrenia and in 1000 controls, and combination analyses with groups from other places including China and Hong Kong. Other than the genome-wide association study, gene sequencing for purported candidate genes and copy number variation analysis will be performed. Neurocognitive intermediate phenotypes will be employed to deconstruct the complex schizophrenia phenotype in a bid to improve association findings. Promising leads from longitudinal gene and protein expression in ultra-high-risk subjects who develop psychosis and schizophrenia (in a parallel study) will be followed up as candidate genes and sequenced in the genetic analysis. Functional analysis forms the last stage of this integrated approach., Conclusion: This integrated genetic and genomic approach will hopefully help in further characterizing and deepening our understanding of molecular pathophysiological mechanisms underlying schizophrenia., (© 2011 Blackwell Publishing Asia Pty Ltd.)

1. Fibrin gel has been used as a carrier of angiogenic molecules to promote neovascularization in animal models of limb ischaemia. However, little is known about the effects of fibrin itself under such pathological conditions. Accordingly, the present study tested the efficacy of fibrin in a rabbit model of acute hindlimb ischaemia. 2. Unilateral ischaemia was induced by resection of the left femoral artery. Seven days after surgery, fibrin particles (FP), which were free of fibrinogen, thrombin and vascular endothelial growth factor, were injected directly into the ischaemic thigh muscles. Twenty-four rabbits were divided into four groups, namely a control group receiving phosphate-buffered saline and three FP-treated groups receiving 5, 10 or 20 mg FP. 3. Collateral vessel development and limb perfusion were assessed by angiography, measuring the calf blood pressure ratio (BPR), thermographic scanning and the histological determination of capillary density. 4. At day 35 post-surgery, the treatment with 5 mg FP produced an augmentation of collateral vessel development (P < 0.01), increased numbers of capillaries (P < 0.05) and improved perfusion manifested by a higher blood flow (P < 0.01) and calf BPR (P < 0.05) compared with controls. Treatment with 10 and 20 mg FP had similar effects to those observed with 5 mg FP. 5. The present study reveals that FP promotes angiogenesis in a rabbit model of hindlimb ischaemia, thus providing a feasible approach to therapeutic angiogenesis in ischaemic diseases.