A new member of the layered pseudo‐1D material family—monoclinic gallium telluride (GaTe)—is synthesized by physical vapor transport on a variety of substrates. The 010 atomic chains and the ...resulting anisotropic behavior are clearly revealed. The GaTe flakes display multiple sharp photoluminescence emissions in the forbidden gap, which are related to defects localized around selected edges and grain boundaries.
Abstract
Although the upper-layer dynamics of the Loop Current and eddies in the Gulf of Mexico are well studied, the understanding of how they are coupled to the deep flows is limited. In this work, ...results from a numerical model are analyzed to classify the expansion, shedding, retraction, and deep-coupling cycle (the Loop Current cycle) according to the vertical mass flux across the base of the Loop. Stage A is the “Loop reforming” period, with downward flux and deep divergence under the Loop Current. Stage B is the “incipient shedding,” with strong upward flux and deep convergence. Stage C is the “eddy migration,” with waning upward flux and deep throughflow from the western Gulf into the Yucatan Channel. Because of the strong deep coupling between the eastern and western Gulf, the Loop’s expansion is poorly correlated with deep flows through the Yucatan Channel. Stage A is longest and the mean vertical flux under the Loop Current is downward. Therefore, because the net circulation around the abyssal basin is zero, the abyssal gyre in the western Gulf is cyclonic. The gyre’s strength is strongest when the Loop Current is reforming and weakest after an eddy is shed. The result suggests that the Loop Current cycle can force a low-frequency time scales ∼ shedding periods; O(months) abyssal oscillation in the Gulf of Mexico.
OBJECTIVES: To evaluate the prevalence of malnutrition and its impact on mortality, functional decline and cognitive impairment among elder residents in long-term care settings. DESIGNS: A ...prospective cohort study. SETTINGS: Two veteran homes in Taiwan. PARTICIPANTS: A total of 1,248 male residents aged equal or more than 65 years. MEASUREMENTS: Charlson’s comorbidity index (CCI), Minimum data set (MDS), resident assessment protocols (RAP), Activity of daily living-Hierarchy scale, Cognitive Performance Scale, MDS Social engagement scale. RESULTS: The mean age of participants is 83.1 ± 5.1 years, and the prevalence of malnutrition was 6.1%. Inadequate dietary content (57.9%) and unintentional weight loss (31.6%) account for the majority of malnutrition identified by MDS tool. Higher 18-month mortality rate (25% vs. 14.2%), higher baseline CCI (median 1 vs. 0), and higher baseline sum of RAP triggers (median 8.5 vs. 5) were noted among residents with malnutrition. Furthermore, malnutrition was shown predictive for functional decline (OR: 3.096, 95% CI: 1.715-5.587) and potential cognitive improvement (OR: 2.469, 95% CI: 1.188-5.128) among survivors after adjustment for age, body mass index and CCI. CONCLUSION: Malnutrition among elder men residing in veteran homes was associated with multimoridities and higher care complexity, and was predictive for mortality and functional decline.
Aims.
From the early days in
γ
-ray astronomy, locating the origin of GeV emission within the core of an active galactic nucleus (AGN) persisted as an open question; the problem is to discern between ...near- and far-site scenarios with respect to the distance from the super massive central engine. We investigate this question under the light of a complete sample of low synchrotron peak (LSP) blazars which is fully characterized along many decades in the electromagnetic spectrum, from radio up to tens of GeV. We consider the high-energy emission from bright radio blazars and test for synchrotron self-Compton (SSC) and external Compton (EC) scenarios in the framework of localizing the
γ
-ray emission sites. Given that the inverse Compton (IC) process under the EC regime is driven by the abundance of external seed photons, these photons could be mainly ultraviolet (UV) to X-rays coming from the accretion disk region and the broad-line region (BLR), therefore close to the jet launch base; or infrared (IR) seed photons from the dust torus and molecular cloud spine-sheath, therefore far from jet launch base. We investigate both scenarios, and try to reveal the physics behind the production of
γ
-ray radiation in AGNs which is crucial in order to locate the production site.
Methods.
Based on a complete sample of 104 radio-selected LSP blazars, with 37 GHz flux density higher than 1 Jy, we study broadband population properties associated with the nonthermal jet emission process, and test the capability of SSC and EC scenarios to explain the overall spectral energy distribution (SED) features. We use SEDs well characterized from radio to
γ
rays, considering all currently available data. The enhanced available information from recent works allows us to refine the study of Syn to IC peak correlations, which points to a particular
γ
-ray emission site.
Results.
We show that SSC alone is not enough to account for the observed SEDs. Our analysis favors an EC scenario under the Thomson scattering regime, with a dominant IR external photon field. Therefore, the far-site (i.e., far from the jet launch) is probably the most reasonable scenario to account for the population properties of bright LSP blazars in cases modeled with a pure leptonic component. We calculate the photon energy density associated with the external field at the jet comoving frame to be
U
′
ext
= 1.69 × 10
−2
erg cm
−3
, finding good agreement to other correlated works.
Detonation nanodiamonds have found numerous potential applications in a diverse array of fields such as biomedical imaging and drug delivery. Here, we systematically characterized non-functionalized ...and polyglycerol-functionalized detonation nanodiamond particles (DNPs) dispersed in aqueous suspensions at different ionic strengths (∼1.0 × 10
to 1.0 × 10
M) via dynamic light scattering and cryogenic transmission electron microscopy. For these colloidal suspensions, the total potential energies of interactions between a pair of DNPs were theoretically calculated using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory plus the fitting of the Boltzmann distribution to the interparticle spacing distribution of the colloidal DNPs. These investigations revealed that the non-functionalized DNPs are dispersed in aqueous media through the long-range (>10 nm) and weak (<7
) electrical double-layer repulsive interaction, while the driving force on dispersion of polyglycerol-functionalized DNPs is mostly derived from the short-range (<2 nm) and strong (∼55
) steric repulsive potential barrier generated by the polyglycerol. Moreover, our results show that the truly monodispersed and individually dispersed DNP colloids, forming no aggregates in aqueous suspensions, are available by both functionalizing DNPs by polyglycerol and increasing ionic strength of suspending media to ≳1.0 × 10
M.
The focal plane camera is the core component of the Wide Field-of-view Cherenkov/fluorescence Telescope Array (WFCTA) of the Large High-Altitude Air Shower Observatory (LHAASO). Because of the ...capability of working under moonlight without aging, silicon photomultipliers (SiPM) have been proven to be not only an alternative but also an improvement to conventional photomultiplier tubes (PMT) in this application. Eighteen SiPM-based cameras with square light funnels have been built for WFCTA. The telescopes have collected more than 100 million cosmic ray events and preliminary results indicate that these cameras are capable of working under moonlight. The characteristics of the light funnels and SiPMs pose challenges (e.g. dynamic range, dark count rate, assembly techniques). In this paper, we present the design features, manufacturing techniques and performances of these cameras. Finally, the test facilities, the test methods and results of SiPMs in the cameras are reported here.
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