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Over the past decades, the treatment of ST-segment elevation myocardial infarction (STEMI) has been redefined with the incorporation of evidence from multiple clinical trials. Recommendations from guidelines are updated regularly to reduce morbidity and mortality. However, heterogeneous care systems, physician perspectives, and patient behavior still lead to a disparity between evidence and clinical practice. The quality of care has been established and become an integral part of modern healthcare in order to increase the likelihood of desired health outcomes and adhere to professional knowledge. For patients with STEMI, measuring the quality of care is a multifactorial and multidimensional process that cannot be estimated solely based on patients' clinical outcomes. The care of STEMI is similar to the concept of "the chain of survival" that emphasizes the importance of seamless integration of five links: early recognition and diagnosis, timely reperfusion, evidence-based medications, control of cholesterol, and cardiac rehabilitation. Serial quality indicators, reflecting the full spectrum of care, have become a widely used tool for assessing performance. Comprehension of every aspect of quality assessment and indicators might be too demanding for a physician. However, it is worthwhile to understand the concepts involved in quality improvement since every physician wants to provide better care for their patients. This article reviews a fundamental approach to quality care in STEMI.

The threshold voltages at the onset of conduction for electron and hole branches can provide information on band gap values or interface states in a gap. We measured conductivity of bilayer graphene encapsulated by hexagonal boron nitride as a function of back and top gates, where another bilayer graphene is used as a top gate. From the measured conductivity the transport gap values were extracted assuming zero interface trap states, and they are close to the theoretically expected gap values. From a little discrepancy an average density of interface states per energy within a band gap ( Dit) is also estimated. The data clearly show that Dit decreases as a bilayer graphene band gap increases rather than being constant. Despite the decreasing trend of Dit, interestingly the total interface states within a gap increases linearly as a band gap increases. This is because of ∼2 × 1010 cm-2 interface states localized at band edges even without a band gap, and other gap states are equally spread over the gap.

Medial vascular calcification has emerged as a key factor contributing to cardiovascular mortality in patients with chronic kidney disease (CKD). Vascular smooth muscle cells (VSMCs) with osteogenic transdifferentiation play a role in vascular calcification. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors reduce reactive oxygen species (ROS) production and calcified-medium–induced calcification of VSMCs. This study investigates the effects of dextromethorphan (DXM), an NADPH oxidase inhibitor, on vascular calcification. We used in vitro and in vivo studies to evaluate the effect of DXM on artery changes in the presence of hyperphosphatemia. The anti-vascular calcification effect of DXM was tested in adenine-fed Wistar rats. High-phosphate medium induced ROS production and calcification of VSMCs. DXM significantly attenuated the increase in ROS production, the decrease in ATP, and mitochondria membrane potential during the calcified-medium–induced VSMC calcification process (p &lt, 0.05). The protective effect of DXM in calcified-medium–induced VSMC calcification was not further increased by NADPH oxidase inhibitors, indicating that NADPH oxidase mediates the effect of DXM. Furthermore, DXM decreased aortic calcification in Wistar rats with CKD. Our results suggest that treatment with DXM can attenuate vascular oxidative stress and ameliorate vascular calcification.

Rationale: Lymphoma with an initial manifestation of ascites and peritoneal invasion is rare. Patient concerns: A 65-year-old woman presented to the emergency department with a 3-week history of abdominal distention, anorexia, and night sweating, and a 2-week history of melena. She was a silent hepatitis B virus carrier. Abdominal ultrasound showed massive ascites without cirrhosis. Abdominal computed tomography revealed ascites, infiltrative peritoneal lesions with omental cake appearance, and lymphadenopathies. Diagnosis: We performed paracentesis and the ascites cytology was obtained. The patient also underwent esophagogastroduodenoscopy, which showed ulcerative tumors in the stomach. Both ascites cytology and pathology of the gastric tumors confirmed the diagnosis of B-cell lymphoma. Interventions: This patient received 7 cycles of chemotherapy. Outcomes: Follow-up imaging studies revealed partial remission of lymphoma, but an enlargement of residual tumors in omentum and mesentery, which resulted in intractable ascites and rapid deterioration of performance status. Despite a change of regimen of chemotherapy, this patient expired 10 months after diagnosis. Lessons: Lymphoma should be one of the differential diagnoses in patients with intractable ascites not attributable to other comorbidities.

Objectives: Although the association between systemic infection and cardiovascular events has been identified, uncertainty remains regarding the incidence and prognosis of sepsis in acute myocardial infarction (AMI). The purpose of this research was to assess the impact of sepsis on survival after first AMI. Methods: This was a nationwide cohort study involving the analysis of data from the Taiwan National Health Insurance Research Database for the period 2000–2012, for patients with a primary diagnosis of first AMI. Among the 186 112 prospective patients, sepsis was diagnosed in 13 065 (7.0%). The propensity score matching technique was used to match 13 065 controls to the patients with sepsis and AMI with similar baseline characteristics. Cox proportional hazards regression models, including sepsis, percutaneous coronary intervention (PCI), and comorbidities, were performed to further evaluate the different influences on the mortality risk in patients hospitalized for first AMI. Results: Overall, the 12-year survival rate was lower in AMI patients with sepsis than in those without sepsis (log rank p-value

Although the correlation between systemic infection and cardiovascular events has been identified, uncertainty still exists in the incidence and prognosis of sepsis in acute myocardial infarction (AMI). The purpose of our research was to evaluate the impact of sepsis on survival after first AMI.

The bioresorbable material of the stent frame with the capability of providing mechanical support and drug-delivery functions have been developed to attempt to improve long-term outcomes. However, there are still limited publications about long-term outcomes of bioresorbable scaffolds (BRS) in Asia

We report the fabrication and experimental investigation of Ge-SixGe1-xcore-shell nanowire (NW) tunneling field-effect transistors (TFETs), consisting of p-i-n device structures realized by low-energy ion implantation. We investigate the NW TFET device characteristics as a function of drain doping, channel length, and temperature. Our devices show on-state currents of up to ION ~ 5μA/μm, with an ambipolar behavior that can be suppressed by varying the drain doping concentration. The subthreshold swing of NW TFETs shows little temperature dependence down to 77 K, consistent with band-to-band tunneling as being the dominant carrier injection mechanism.

In this paper, we present a systematic study of the role of metal/semiconductor nanowire (NW) contact in back-gated Ge and Si NW Schottky-barrier (SB) FETs. Our results show that the performance of such devices is largely dominated by the carrier injection efficiency at the source contact, which, in turn, is controlled by metal contact depth and gate bias. Using low-temperature annealing of back-gated Ge and Si NW SB FETs with nickel (Ni) contacts as source and drain, we monitor the evolution of the device current as the contact metal progressively diffuses into the NWs. The drain current, which is measured at a given gate and drain bias, first increases as the contact metal diffuses into the NW, reaches a maximum, and subsequently decreases. These results can be explained by the interplay between carrier injection efficiency through the metal/NW SB, which increases with the metal contact depth, and the number of available states in the NW between contact and the bottom oxide, which decreases with the metal contact depth.

We demonstrate the fabrication of high-performance Ge-SixGe1-x core-shell nanowire (NW) field-effect transistors with highly doped source (S) and drain (D) and systematically investigate their scaling properties. Highly doped S and D regions are realized by low-energy boron implantation, which enables efficient carrier injection with a contact resistance much lower than the NW resistance. We extract key device parameters, such as intrinsic channel resistance, carrier mobility, effective channel length, and external contact resistance, as well as benchmark the device switching speed and on/off current ratio.

Spectroscopic ellipsometry (SE) is applied to characterize Si columnar nanostructures. By employing effective medium approximation (EMA) theory, Si nanorods are treated as a graded layer with each sub-layer modeled as a mixture of Si and voids with varying porosity fraction. In addition, the rigorous coupled-wave analysis and finite-element Green's function method were used in modeling Si naorods as a stack of disks with varying diameters and thicknesses, and the calculations are in satisfactory agreement with the measurement results.

We report the enhanced performance of Ge nanowire (NW) tunneling field-effect transistors (TFETs), realized using a millisecond flash-assisted rapid thermal process (fRTP) for dopant activation. The electrical characteristics of our fRTP-activated NW TFETs exhibit maximum drive currents up toImax ~ 28 μA/μm at Vdd = -3 V and improved subthreshold swings. By comparison, NW TFETs realized using conventional RTP for dopant activation show an order of magnitude lower current. We attribute these findings to a more abrupt doping profile at the tunnel junction, owing to reduced dopant diffusion and improved dopant activation.

We study the device characteristics of Si-capped GexC1-x pMOSFETs from room temperature down to 77 K. The output characteristics of these devices reveal a negative differential resistance (NDR) at temperatures below 150 K. Our measurements indicate a higher effective carrier mobility in the buried-channel GexC1-x with respect to the Si-reference sample, which suggests that the observed NDR is due to real-space transfer of hot holes from the higher mobility GexC1-x channel layer into the lower mobility Si cap layer.

Semiconductor nanowires are potential candidates for applications in quantum information processing, Josephson junctions and field-effect transistors and provide a unique test bed for low-dimensional physical phenomena. The ability to fabricate nanowire heterostructures with atomically flat, defect-free interfaces enables energy band engineering in both axial and radial directions. The design of radial, or core-shell, nanowire heterostructures relies on energy band offsets that confine charge carriers into the core region, potentially reducing scattering from charged impurities on the nanowire surface. Key to the design of such nanoscale heterostructures is a fundamental understanding of the heterointerface properties, particularly energy band offsets and strain. The charge-transfer and confinement mechanism can be used to achieve modulation doping in core-shell structures. By selectively doping the shell, which has a larger bandgap, charge carriers are donated and confined in the core, generating a quasi-one-dimensional electron system with higher mobility. Here, we demonstrate radial modulation doping in coherently strained Ge-SixGe1-x core-shell nanowires and a technique to directly measure their valence band offset. Radial modulation doping is achieved by incorporating a B-doped layer during epitaxial shell growth. In contrast to previous work showing site-selective doping in Ge-Si core-shell nanowires, we find both an enhancement in peak hole mobility compared with undoped nanowires and observe a decoupling of electron transport in the core and shell regions. This decoupling stems from the higher carrier mobility in the core than in the shell and allows a direct measurement of the valence band offset for nanowires of various shell compositions.

We report the fabrication and experimental investigation of Ge-Si x Ge 1-x core-shell nanowire (NW) tunneling field effect transistors (TFETs). Low energy ion implantation was used to highly dope the NW TFET source (S) and drain (D). The NW TFETs show ON-state currents of up to I ON ∼ 5 µA/µm, and the ambipolar behavior is suppressed by achieving asymmetric doping concentrations at S/D. Furthermore, the NW TFET subthreshold slope (SS) shows little temperature dependence down to 77K, consistent with band-to-band tunneling (BTBT) being the dominant carrier injection mechanism.

We report the growth and characterization of Ge-Si x Ge 1-x core-shell nanowires. Using a combination of vapor-liquid-solid nanowire growth and ultra-high-vacuum chemical vapor deposition conformal growth, we demonstrate the realization of epitaxial Ge-Si x Ge 1-x core-shell nanowire heterostructures with tunable shell content. We investigate the intrinsic electronic properties of Ge-Si x Ge 1-x core-shell nanowires using back-gate dependent two- and four-terminal resistance measurements, and demonstrate high performance Ge-Si x Ge 1-x core-shell nanowire field-effect transistors with highly doped source and drain.

Semiconductor (e.g. silicon, germanium) nanowires have gained interest as an attractive platform to fabricate field effect transistors devices because of their reduced short channel effects by comparison to planar devices [1]. The realization of high performance nanowire devices however has been stymied primarily by large source (S) and drain (D) contact resistances. Here we report the fabrication and electrical characterization of the top-gated Ge-Si x Ge 1−x core-shell nanowire field-effect transistors (NWFETs) with highly doped S/D. The highly doped S/D, realized using low energy ion implantation, allows an efficient carrier injection into the NWFET channel.

Self assembled semiconductor (e.g. silicon, germanium) nanowires represent an attractive platform to fabricate field effect transistors devices that can reduce short channel effects in by comparison planar devices. Back-gated field effect transistors with metal contacts represent a common device fabrication method employed to test the electronic properties of semiconductor nanowires. Using a systematic electrical characterization study of back-gated germanium nanowire device with nickel (Ni) contacts, here we show experimentally and theoretically that the metal contact depth, controlled by annealing the device at moderate temperatures, critically impacts the device performance. Interestingly, as the metal contact diffuses into the nanowire during annealing, the device current shows a non monotonic dependence as function of the metal contact penetration depth.

Electrical injection of spin-polarized electrons into a semiconductor, large spin diffusion length, and an integration friendly platform are desirable ingredients for spin-based devices. Here we demonstrate lateral spin injection and detection in germanium nanowires, by using ferromagnetic metal contacts and tunnel barriers for contact resistance engineering. Using data measured from over 80 samples, we map out the contact resistance window for which lateral spin transport is observed, manifestly showing the conductivity matching required for spin injection. Our analysis, based on the spin diffusion theory, indicates that the spin diffusion length is larger than 100 {\mu}m in germanium nanowires at 4.2 K.

This work presents the effects of Si-cap thickness and temperature on device performance of buried channel Si/Ge1−xCx/Si p-MOSFETs. The silicon-cap thickness (3–9 nm), as well as the operating temperature (300 K down to 77 K), plays a significant role on device performance in terms of drive current, sub-threshold slope, effective hole mobility and Ion–Ioff ratio. The 7 nm Si-capped device demonstrates highest mobility enhancement because of reduced remote Coulomb scattering. In addition, the valence band offset between the Si-cap/Ge1−xCx interface was quantitatively extracted by fitting the stair-case behavior of split C–V characteristics with self-consistent simulations of one-dimensional Poisson and Schrodinger equations.

We demonstrate dual-gated germanium (Ge)-silicon germanium (SixGe1−x) core-shell nanowire (NW) field effect transistors (FETs) with highly doped source (S) and drain (D). A high-κ HfO2 gate oxide was deposited on the NW by atomic layer deposition, followed by TaN gate metal deposition. The S and D regions of NW were then doped using low energy (3 keV) boron (B) ion implantation with a dose of 1015 cm−2. The electrical characteristics of these devices exhibit up to two orders of magnitude higher current and an improved ON/OFF current ratio by comparison to dual-gated NW FET with undoped S/D.

We investigate the doping of germanium (Ge)–silicon germanium (SixGe1−x) core-shell nanowires (NWs) by low energy (3 keV) boron (B) ion implantation. Ge–SixGe1−x core-shell NWs were implanted with B atoms at different doses from 1×1014 to 1×1015 cm−2, and subsequently annealed for dopant activation. Using four-point, gate-dependent resistance measurements, we determine the resistivity, doping levels, and contacts resistance of the B-doped Ge–SixGe1−x NWs. Our findings show that depending on the implantation dose, the doping level of B-doped NWs ranges from 1×1018 to 2×1020 cm−3.

Low refractive index of a stalagmitelike high-aspect-ratio Si nanopillar array on Si dry etched using a self-aggregated Ni nanodot mask is demonstrated, which exhibits two minimum reflectances of 1.23 and 1.4 with corresponding refractive indices of 1.25 and 1.48 at 400 and 1200nm, respectively. Angular dependency of the transverse electrical mode reflectance at 632.8nm of the surface roughened Si nanopillar array is released, and the Brewster angle of 63° with equivalent refractive index of 1.5 is determined.