The detection of pollutant and toxic gases has attracted extensive attention due to the growing environmental issues. In the present investigation, free-based tetraphenyl porphyrin (TPP) and iron ...tetraphenyl porphyrin (FeTPP) are used to functionalize thermally reduced graphene oxide (rGO) and further used for the detection of carbon monoxide (CO). TPP and FeTPP functionalized rGO (FeTPP@rGO) sensors are fabricated on a glass substrate with thermally coated copper electrodes. The materials are characterized with X-ray diffraction (XRD), Fourier transforms infrared (FTIR) spectroscopy, Raman spectroscopy, UV–visible spectroscopy, atomic force microscopy, scanning electron microscopy, and energy dispersive spectroscopy. The current–voltage (
I
–
V
) characteristics have also been studied to demonstrate the operation of the device. In addition, the FeTPP@rGO device shows high sensitivity toward the detection of CO. By testing in the chemiresistive sensing modality, the as-fabricated device shows good response and recovery of 60 s and 120 s, respectively, with a low detection limit of 2.5 ppm.
Several risk scores have been developed to predict symptomatic intracerebral hemorrhage (SICH) after acute reperfusion therapy for ischemic stroke. We compared the performance of established risk ...scores in predicting SICH after EVT under different SICH criteria.
A total of 258 patients with anterior circulation large vessel occlusion who received EVT in two medical centers of Taiwan were recruited. Three definitions of SICH, the European Collaborative Acute Stroke Study II (ECASS II), ECASS III, and the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST), were used. The HAT, SITS-SICH, SEDAN, and TAG risk scores were applied. Logistic regression and area under the receiver operating characteristic curve (AUC) were used to evaluate the performance of each risk model.
In the 258 included patients (mean age, 71.9 ± 11.8 years; men, 48.1%), the observed rates of SICH according to ECASS II, ECASS III, and SITS-MOST criteria were 10.1%, 5.0%, and 4.7%, respectively. Higher glucose level (>160 mg/dL) and unsuccessful recanalization independently predicted SICH under all criteria. Among the different risk scores, only SEDAN and TAG consistently predicted SICH. SEDAN and TAG scores exhibited the highest AUC in predicting SICH for ECASS III (SEDAN 0.72, TAG 0.72) and SITS-MOST (SEDAN 0.73, TAG 0.70) criteria.
Among various risk scores, the TAG and SEDAN scores best predict SICH after EVT. Higher glucose level and unsuccessful recanalization, which are included in the TAG and SEDAN scores, are independent risk factors of SICH in the present cohort, highlighting their detrimental effects.
To determine the incidence and risk of Parkinson disease (PD) in patients with Sjögren syndrome (SS) according to a nationwide population-based database.In total, 12,640 patients in the SS cohort and ...50,560 in the non-SS cohort were enrolled from Taiwan's National Health Insurance Research Database from 2000 to 2010. We used the Cox multivariable proportional hazards model to determine the risk factors for PD in the SS cohort.We observed an increased incidence of PD in patients with SS, with a crude hazard ratio (HR) of 1.40 and an adjusted HR (aHR) of 1.23. The cumulative incidence of PD was 1.95% higher in the SS cohort than in the non-SS cohort. The SS cohort had an elevated HR under medication use, namely cevimeline and pilocarpine (crude HR, 1.28), hydroxychloroquine (crude HR, 1.43; aHR, 1.46), and methylprednisolone (crude HR, 2.21; aHR, 1.49). Patients receiving other non-hydroxychloroquine immunosuppressant therapies had a lower risk (aHR, 0.86) of PD. Furthermore, patients with SS aged 20 to 49 years had a 1.93-fold higher risk of PD than did those without SS (aHR, 1.93). The risk of PD was higher (aHR, 2.20) in patients with SS without comorbidities than in those with comorbidities. The aHR of PD significantly increased when the follow-up period exceeded 9 years (aHR, 1.93).We determined an increased risk of PD in patients with SS. Further investigation is warranted to determine the possible underlying mechanisms and the potential role of non-hydroxychloroquine immunosuppressants in ameliorating PD.
Tuning the optical and electrical properties by stacking different layers of two-dimensional (2D) materials enables us to create unusual physical phenomena. Here, we demonstrate an alternative ...approach to enhance charge separation and alter physical properties in van der Waals heterojunctions with type-II band alignment by using thin dielectric spacers. To illustrate our working principle, we implement a hexagonal boron nitride (h-BN) sieve layer in between an InSe/GeS heterojunction. The optical transitions at the junctions studied by photoluminescence and the ultrafast pump-probe technique show quenching of emission without h-BN layers exhibiting an indirect recombination process. This quenching effect due to strong interlayer coupling was confirmed with Raman spectroscopic studies. In contrast, h-BN layers in between InSe and GeS show strong enhancement in emission, giving another degree of freedom to tune the heterojunction property. The two-terminal photoresponse study supports the argument by showing a large photocurrent density for an InSe/h-BN/GeS device by avoiding interlayer charge recombination. The enhanced charge separation with h-BN mediation manifests a photoresponsivity and detectivity of 9 × 10
A W
and 3.4 × 10
Jones, respectively. Moreover, a photogain of 1.7 × 10
shows a high detection of electrons for the incident photons. Interestingly, the photovoltaic short-circuit current is switched from positive to negative, whereas the open-circuit voltage changes from negative to positive. Our proposed enhancement of charge separation with 2D-insulator mediation, therefore, provides a useful route to manipulate the physical properties of heterostructures and for the future development of high-performance optoelectronic devices.
This study proposes a new adaptive template attack scheme for extracting secret keys in Montgomery-ladder (ML)-based elliptic curve cryptography (ECC) by effectively exploiting the leakage difference ...between key bits 1 and 0. To determine the key length and number of computation cycles per bit of the ECC to be attacked, the proposed adaptive attack employs an adaptive leakage-windowing technique and correlation analysis on the power trace obtained from an ECC module with a secret key. The point of interest (POI) is identified at the bit with the maximum difference in leakage between key bits 1 and 0 using the leakage window per bit. The trace from the victim ECC hardware with secret key is compared to those collected in prior templates with key bits 1 and 0 to recover the key. To validate the performance, a Xilinx Artix-7 FPGA chip was used to implement an Edward-curve digital signature algorithm (EdDSA) with Ed25519 and SHA-512 accelerators. The experimental results show a favorable key recovery rate of 100%. Further attack results are presented for the ECC modules with advanced countermeasures against side-channel attack, such as projective coordinate and/or scalar randomization. It is validated that the proposed adaptive attack is able to exploit successfully 100% of the keys of ML-based ECC accelerators without and with countermeasures of projective coordinate or scalar randomization. Only a heavily resource-consumed ECC module with implemented projective coordinate, scalar randomization, and a cryptographic secure random number generator is capable of defending the proposed attack.
The freedom from efficiency droop motivates monochromatic lasers to progress in general lighting applications due to the demand for more efficient and sustainable light sources. Still, a white light ...based on monochromatic lasers with high lighting quality, such as a high color rendering ability, an angle-independent output, and a speckle-free illumination, has not yet been fabricated nor demonstrated. Random lasers, with the special mechanism caused by multiple scattering, the angle-free emission, and the uncomplicated fabrication processes, inspire us to investigate the feasibility of utilizing them in general lighting. In this work, a white random laser with a high color rendering index (CRI) value, regardless of pumping energy and observing direction, was performed and discussed. We also investigated the stability of white RL as its CIE chromaticity coordinates exhibit negligible differences with increasing pump energy density, retaining its high-CRI measurement. Also, it exhibits angle-independent emission while having a high color rendering ability. After passing through a scattering film, it generated no speckles compared to the conventional laser. We demonstrated the advances in white laser illumination, showing that a white random laser is promising to be applied for high-brightness illumination, biological-friendly lighting, accurate color selections, and medical sensing.
A series of unique heterofunctionalized asymmetric giant “bolaform-like” surfactants composed of a polystyrene (PS) chain end-capped with two distinctly functionalized polyhedral oligomeric ...silsesquioxane (POSS) cages one with seven isobutyl groups (BPOSS) and the other with 14 hydroxyl groups (DPOSS) were designed and synthesized, and their self-assembly behaviors were investigated. Combining the atomic transfer radical polymerization using a BPOSS-containing initiator and the sequential “click” approach, BPOSS-PS n -DPOSS samples with different PS molecular weights were obtained. Investigation on their self-assembly behaviors revealed that they could form a variety of different ordered structures, such as lamellae, double gyroids, hexagonally packed cylinders, and body-center-cubic spheres, with feature sizes around or below 10 nm. Functional groups on the POSS cages govern the interaction parameters of different POSS cages with the PS interconnect and thus their compatibility. Hydrophilic DPOSS cages are phase-separated from the PS domains, while BPOSS cages are favorably associated within the PS domains. However, in the lamellae phase where the geometry of confinement seems compatible with the close-packing of BPOSS, the BPOSS cages tend to crystallize due to the existence of the flat interfaces, leading to further phase separation of the BPOSS cages from the PS interconnects. These results provide insights into the design of novel self-assembling materials based on POSS–polymer conjugates toward desired physical properties.
CISD2 is a causative gene associated with Wolfram syndrome (WFS). However, it remains a mystery as to how the loss of CISD2 causes metabolic defects in patients with WFS. Investigation on the role ...played by Cisd2 in specific cell types may help us to resolve these underlying mechanisms. White adipose tissue (WAT) is central to the maintenance of energy metabolism and glucose homeostasis in humans. In this study, adipocyte-specific Cisd2 knockout (KO) mice showed impairment in the development of epididymal WAT (eWAT) in the cell autonomous manner. A lack of Cisd2 caused defects in the biogenesis and function of mitochondria during differentiation of adipocytes in vitro. Insulin-stimulated glucose uptake and secretion of adiponectin by the Cisd2 KO adipocytes were decreased. Moreover, Cisd2 deficiency increased the cytosolic level of Ca(2+) and induced Ca(2+)-calcineurin-dependent signaling that inhibited adipogenesis. Importantly, Cisd2 was found to interact with Gimap5 on the mitochondrial and ER membranes and thereby modulate mitochondrial Ca(2+) uptake associated with the maintenance of intracellular Ca(2+) homeostasis in adipocytes. Thus, it would seem that Cisd2 plays an important role in intracellular Ca(2+) homeostasis, which is required for the differentiation and functioning of adipocytes as well as the regulation of glucose homeostasis in mice.
Consistent 2D and 3D thermal boundary conditions for thermal lattice Boltzmann simulations are proposed. The boundary unknown energy distribution functions are made functions of known energy ...distribution functions and correctors, where the correctors at the boundary nodes are obtained directly from the definition of internal energy density. This boundary condition can be easily implemented on the wall and corner boundary using the same formulation. The discrete macroscopic energy equation is also derived for a steady and fully developed channel flow to assess the effect of the boundary condition on the solutions, where the resulting second order accurate central difference equation predicts continuous energy distribution across the boundary, provided the boundary unknown energy distribution functions satisfy the macroscopic energy level. Four different local known energy distribution functions are experimented with to assess both this observation and the applicability of the present formulation, and are scrutinized by calculating the 2D thermal Poiseuille flow, thermal Couette flow, thermal Couette flow with wall injection, natural convection in a square cavity, and 3D thermal Poiseuille flow in a square duct. Numerical simulations indicate that the present formulation is second order accurate and the difference of adopting different local known energy distribution functions is, as expected, negligible, which are consistent with the results from the derived discrete macroscopic energy equation.
This paper describes the preparation of nanoarrays composed of silver nanoparticles (AgNPs: 20–50 nm) for use as surface-enhanced Raman scattering (SERS) substrates. The AgNPs were grown on porous ...anodic aluminum oxide (AAO) templates by electrochemical plating, and the inter-channel gap of AAO channels is between 10 and 20 nm. The size and interparticle gap of silver particles were adjusted in order to achieve optimal SERS signals and characterized by scanning electron microscopy, atomic force microscopy, and Raman spectroscopy. The fluctuation of SERS intensity is about 10–20% when measuring adenine solutions, showing a great reproducible SERS sensing. The nanoparticle arrays offer a large potential for practical applications as shown by the SERS-based quantitative detection and differentiation of adenine (A), thymine (T), cytosine (C), guanine (G), β-carotene, and malachite green. The respective detection limits are <1 ppb for adenine and <0.63 ppm for β-carotene and malachite green, respectively.
Graphical Abstract
Uniform and reproducible Raman enhancement enabled by Ag nanoparticle array embedded in anodic aluminum oxide differentiates and helps quantify DNA canonical nucleobases (adenine, thymine, cytosine, and guanine).
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