Dual-Gas Sensor Employing Wavelength-Stabilized Tunable Diode Laser Absorption Spectroscopy and H-Infinity Filtering Algorithm.

A compact dual-gas sensor based on the two near-infrared distributed feedback diode lasers and a multipass cell has been established for the simultaneous measurement of methane (CH) and acetylene (CH). The time division multiplexing calibration-free direct absorption spectroscopy is used to eliminate the cross interference in the application of multicomponent gas sensors. A wavelength stabilization technique based on the proportion integration differentiation feedback control is developed to suppress laser wavelength drift and an H-infinity (H) filter algorithm to reduce the system noise.

Enantioselective Synthesis of Nonfused Eight-Membered O-Heterocycles by Sequential Catalysis.

This work describes a chiral bifunctional squaramide/DBU sequential catalytic strategy for the enantioselective synthesis of nonfused chiral eight-membered O-heterocycles through the asymmetric addition of ynones to β,γ-unsaturated α-ketoesters followed by the regio- and diastereoselective cyclization of the adduct intermediates. Mechanistic experiments revealed that an isomerization process should be involved in the ring formation step, and the origin of the high regioselectivity and diastereoselectivity has also been elucidated by the DFT calculations.

CAS-OPCABG vs OPCABG-alone in patients with asymptomatic carotid Stenosis: Multi-center experience.

Objective: The objective was to evaluate the relationship between carotid stenting and off-pump coronary artery grafting (CAS-OPCABG) and OPCABG only in patients with asymptomatic severe carotid stenosis.

Methods: This study retrospectively included 669 patients with asymptomatic severe carotid artery stenosis who underwent OPCABG at multiple centers. After propensity score matching for baseline characteristics, the study compared two groups of patients with clinical data, early and midterm death, stroke, and myocardial infarction (MI).

The clinical diagnostic value of right-to-left shunt in cryptogenic stroke under right heart contrast echocardiography: a retrospective case-control study.

Background: About 30% of ischemic strokes do not have a clear cause, which is called cryptogenic stroke (CS). Increasing evidence suggests a potential link between CS and right-to-left shunt (RLS). RLS may lead to CS via paradoxical embolic mechanism.

End-of-Life Inpatient Palliative Care for Glioblastoma Multiforme: Lessons Learned from One Case.

Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor with a poor prognosis and limited survival. Patients with GBM have a high demand for palliative care. In our present case, a 21-year-old female GBM patient received inpatient palliative care services including symptom management, mental and psychological support for the patient, psychosocial and clinical decision support for her family members, and pre- and post-death bereavement management for the family.