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• Utilizing a divergent synthetic approach with a common intermediate, multiple natural products were synthesized. • A one-pot process involving Michael addition, aldol reaction, and dehydration simultaneously constructs cyclopentanone. • Conducting screening under high-temperature conditions to reduce the production of isomers. [Display omitted] Total synthesis of (±)-applanatumol W, formal syntheses of (±)-spiroapplanatumine O and (±)-applanatumol B were accomplished using a common intermediate, methyl benzoyl cyclopentane carboxylate 9. This intermediate was synthesized through a one-pot reaction involving formation of Michael acceptor cyclopentenone through first Michael addition of malonate to acrolein, Aldol condensation and dehydration, followed by Michael addition of allylcuprate and subsequent demethoxycarboxylation. [ABSTRACT FROM AUTHOR]

Chronic lead (Pb) exposure is known to cause neuronal inflammation and autophagy dysfunction. However, the precise mechanism by which Pb exposure triggers neuronal autophagy remains elusive. This study aimed to elucidate the molecular mechanisms underlying Pb-induced neuronal autophagy. Inflammation and autophagy are closely interconnected cellular processes, with Toll-like receptor 4 (TLR4) playing a significant role in the inflammatory response to Pb. We observed that inhibiting TLR4 resulted in increased expression of Eukaryotic elongation factor 2 (EEF2), which regulated cellular autophagy. The rats and HT22 cells were utilized to establish chronic Pb exposure models. Our data reveals that Pb exposure promotes neuronal autophagy, activates TLR4, and increases EEF2 expression in rat hippocampus and HT22 cells. Additionally, inhibiting TLR4 partially reverses the Pb-induced increase in autophagy and the enhanced expression of EEF2. Overexpression of EEF2 partially counteracted the autophagy induced by Pb exposure. These findings suggest that Pb-induced activation of TLR4 may upregulate EEF2 expression, thereby leading to augmented neuronal autophagy and potential neuronal dysfunction. • Pb exposure increased neuronal autophagy. • Pb exposure can upregulate gene expression of EEF2 by activating TLR4. • TLR4/EEF2 regulates neuronal autophagy. [ABSTRACT FROM AUTHOR]

Abstract We studied the condensation of exciton-polaritons in pump-induced potential by angle-resolved photoluminescence (PL) measurements at room temperature. The experimental dispersion spectrum shows that under the excitation of a small spot, polaritons in ZnO whispering gallery microcavity condense at a certain state where momentum is non-zero. This is different from the conventional Bose–Einstein condensation (BEC) in which case the polaritons condense at ground state with a zero momentum. The theoretical simulation of condensation shape given by Gross-Pitaevskii equation (GPE) is in good agreement with our experimental observations. Highlights • Polariton condensation at states with non-zero momentum in pump-induced potential was observed in a ZnO microcavity. • To support our experimental results, the simulation of condensation kinetics under nonresonant optical excitation was given by a generalized form of Gross–Pitaevskii equation with gain and loss terms. And the theoretical simulation of condensation shape is in good agreement with our experimental observations. [ABSTRACT FROM AUTHOR]

To estimate the energy storage and release performances of rock pillars in high stress and gain insights into the prevention and control of rockburst hazards from an energy aspect, several series of single-cyclic loading-unloading uniaxial compression tests with different stress levels were conducted on five types of rocks sampled in standard cylinders and prisms. The concepts of relative energy storage potential and ultimate energy storage potential were proposed to evaluate the energy storage performance of the two shaped specimens, and the energy release potential was determined using the residual elastic strain energy index. The results showed that, under similar loading conditions, the relative energy storage potential of rocks was insensitive to the specimen shape, whereas the ultimate energy storage potential and energy release potential were sensitive to both the specimen shape and rock type. Based on the lab results, a theoretical approach of assessing the rockburst (or instability) risk of isolated rock pillars subjected to high geostress was illustrated by estimating its current energy state and ultimate energy storage potential. Importantly, the residual elastic energy of an isolated pillar can also be estimated based on the lab results, according to which the number of supporting devices such as the energy-absorbing bolts needed for scientific and sufficient support of pillar rockburst was quantitatively estimated. This study provides a new method for estimating the desired number of energy-absorbing bolts during rockburst support in engineering practice. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To assess image quality, radiation dose, and diagnostic accuracy of 70-kVp high-pitch computed tomography pulmonary angiography (CTPA) using 40 mL contrast agent and sinogram affirmed iterative reconstruction (SAFIRE) compared to 100-kVp CTPA using 60 mL contrast agent and filtered back projection. Materials and Methods: Eighty patients underwent CTPA at either 70 kVp (group A, n = 40; 3.2 pitch, 40 mL contrast medium, and SAFIRE) or 100 kVp (group B, n = 40; 1.2 pitch, 60 mL contrast medium, and filtered back projection). Signal-to-noise ratio and contrast-to-noise ratio were calculated. Subjective image quality was evaluated using a five-grade scale, and diagnostic accuracy was assessed. Radiation doses were compared. Results: Computed tomography values, signal-to-noise ratio, and contrast-to-noise ratio of pulmonary arteries were higher in group A compared to group B (all P < 0.001). Subjective image quality showed no difference between the two groups (P = 0.559) with good interobserver agreement (κ = 0.647). No difference was found regarding diagnostic accuracy between the two groups (P > 0.05). The effective dose for group A was lower by 80% compared to group B (P < 0.001). Conclusions: 70-kVp high-pitch CTPA with reduced contrast media and SAFIRE provides comparable image quality and substantial radiation dose savings compared to a routine CTPA protocol. [ABSTRACT FROM AUTHOR]

High performance (>15%) organometaltrihalide based solar cells have been demonstrated in recent years to be a promising candidate for low cost photovoltaics and have attracted significant attention in the photovoltaic community. Planar thin film perovskite solar cells, which are more easily fabricated, provide a great platform to investigate the perovskite film properties. Until now, many of the properties of perovskite thin films remain unexplored and the link between film properties and device performances is in need of investigation to further boost the efficiencies of these devices. Here, film transformation of perovskite materials is demonstrated as a critical factor to reach high performance in planar heterojunction CH 3 NH 3 PbI 3− x Cl x solar cells. Reaction induced secondary phases can be observed and carefully controlled by tuning the processing conditions during film formation. The properties of CH 3 NH 3 PbI 3− x Cl x films are investigated and a possible formation pathway is proposed. It is shown that the high performance devices are attainable with a small portion of secondary phases coexisting with CH 3 NH 3 PbI 3 film and power conversion efficiencies of up to 14% are achieved. The correlations between the phases present, device performance and physical properties are discussed to identify the role of the secondary phases in CH 3 NH 3 PbI 3− x Cl x material. [ABSTRACT FROM AUTHOR]

Separate measurement of current density under the different regions of the flow field geometry, i.e. under the land and under the channel, in DMFCs is significant. Such measurements may reveal the mechanisms and the effects of the various coupled parameters that influence the cell performance. Moreover, it can provide guidance for flow field design optimizations and could eventually lead to practical solutions to mitigate methanol crossover and/or its effects. A novel technique is used to directly measure the current density under the land and under the channel separately. In this method, the anode side of the cell is partially catalyzed depending on the area of interest (land, channel or full), whereas the cathode side is always fully catalyzed. The experimental results show that the current density under the land is significantly higher than that under the channel. The drastic difference in performance is attributed to the much higher electrochemical active area (ECA) under the land as shown by CO stripping voltammetry measurements. [ABSTRACT FROM AUTHOR]

Objective : Although the study on the relationship between ABO blood groups and coronary atherosclerosis has a long history, few data is available regarding ABO to severity of coronary atherosclerosis in a large cohort study. Therefore, the present study aimed to investigate the relation of the ABO blood groups to the severity of coronary atherosclerosis assessed by Gensini score (GS) in a large Chinese cohort undergoing coronary angiography. Methods : A total of 2919 consecutive patients undergoing coronary angiography were enrolled, and their baseline characteristics and ABO blood groups were collected. The GS was calculated as 1st tertile (0–10), 2nd tertile (11–36), 3rd tertile (>36) according to angiographic results. The relation of the ABO blood groups to GS was investigated. Results : The frequency of blood group A was significantly higher in the upper GS tertiles (24.4% vs. 28.2% vs. 29.5%, p = 0.032). Multivariable linear regression analysis revealed that blood group A was independently associated with GS ( β = 0.043, p = 0.017). Likewise, multivariable logistic regression analysis showed that group A remained significantly associated with mid-high GS (OR = 1.44, 95% CI 1.16–1.80, p = 0.001), and the group O was showed as a protective factor (OR = 0.77, 95% CI = 0.65–0.92, p = 0.004). Conclusion : In this large Chinese cohort study, the data indicated that there was an association between ABO blood groups and the severity of coronary atherosclerosis. Moreover, the blood group A was an independent risk factor for serious coronary atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: Interdigitated flow field is one of the commonly used designs in proton exchange membrane (PEM) fuel cells. The knowledge of how the current density differs under the inlet channel, the land and the outlet channel, is critical for flow field design and optimization. In this study, the current densities under the inlet channel, the land and the outlet channel in PEM fuel cell with an interdigitated flow field are separately measured using the technique of partially-catalyzed membrane electrode assemblies (MEAs). The experimental results show that the current density under the outlet channel is significantly lower than that under the inlet channel, and the current density under the land is higher than both channels at typical fuel cell operation voltages. Further experimental results show that the pattern of local current density remains the same with different cathode flow rates. [Copyright &y& Elsevier]

Abstract: Background: Three-dimensional contrast-enhanced MR pulmonary angiography (MRPA) is a suitable option for pulmonary embolism (PE) detection. However, there have been few reports on the diagnostic accuracy of MRPA for PE detection in a 3-T MR system. The purpose of this study was to evaluate the accuracy of MRPA in a 3-T MR system to detect acute PE with multidetector CT pulmonary angiography (CTPA) as reference standard. Methods: Twenty-seven patients (18 males and 9 females, mean age 38.9±14.4years) underwent both MRPA and CTPA within 3days (range, 0–3days) for evaluating PE. Pulmonary emboli in MRPA were independently analyzed on a per-patient and per-lobe basis by two radiologists. CTPA was regarded as reference standard, which was evaluated by another two radiologists in consensus. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for PE detection were calculated. Weighted κ values were calculated to evaluate agreement between readers. Results: Twenty-four patients had PE in 55 lung lobes in CTPA, while 3 patients had no PE detected. Readers 1 and 2 correctly detected 47 and 46 lung lobes having clots in 24 and 23 patients, corresponding to sensitivities, specificities, PPV, NPV, and accuracies of 100%, 100%, 100%, 100%, 100%; 100%, 66.7%, 96.0%, 100%, 96.4% on a per-patient basis and 85.5%, 100%, 100%, 90.9%, 94.1%; 83.6%, 93.7%, 90.2%, 89.2%, 89.6% on a per-lobe basis; respectively. Excellent inter-reader agreement (κ values=1.00 and 0.934; both P <0.001) were found for detecting PE on a per-patient and per-lobe analysis. Conclusion: Three-dimensional contrast-enhanced MRPA with a 3-T MR system is a suitable alternative modality to CTPA to detect PE on a per-patient basis based on this small cohort study. [Copyright &y& Elsevier]

Rationale and Objectives: The purposes of this study were to evaluate the prevalence of pulmonary embolism (PE) and renal vein thrombosis in pediatric patients with nephrotic syndrome using combined dual-energy (DE) computed tomographic (CT) pulmonary angiography (CTPA) and renal CT venography and to evaluate whether DE CTPA can improve the detection of PE in these children. Materials and Methods: Thirty-two children (aged ≤ 18 years) were included in this study. All children underwent contrast-enhanced DE CTPA and renal CT venography; seven also underwent follow-up DE CTPA and renal CT venography. The presence of PE was determined by (1) CTPA derived from the average weighted 120-kVp images and (2) DE CTPA using dedicated DE software (syngo DE Lung PBV and syngo DE Lung Vessels), which can extract the iodine contents in lung parenchyma and pulmonary arteries. The prevalence and anatomic distribution of PE on CTPA from the average weighted 120-kVp images and DE CTPA and of renal vein thrombosis on CT venography were recorded by two radiologists in consensus; χ2 tests were used to compare the difference in the detection rate of PE between DE CTPA and conventional CTPA. Results: Of 32 children, nine (28.1%) had PE on the basis of the comprehensive DE CT pulmonary angiographic evaluation (CTPA from average weighted 120-kVp images and perfusion images and vascular images generated using the DE CT software). PE was localized in the lobar pulmonary artery in five patients (55.6%), the segmental pulmonary artery in six (66.7%), and the subsegmental pulmonary artery in five (55.6%). PE was distributed in the right upper lobe in two patients (22.2%), the right middle lobe in two (22.2%), the right lower lobe in five (55.6%), and the left lower lobe in six (66.7%). Compared to the CTPA derived from average weighted 120-kVp data, comprehensive DE CTPA showed solitary subsegmental PE in one additional patient (nine vs eight patients), one additional segmental (11 vs 10 segments), and four additional subsegmental pulmonary emboli (two vs six subsegmental pulmonary emboli) (P > .05 for all). Eight children (25%) had renal vein thrombosis extending to the inferior vena cava (n = 5). Conclusions: The prevalence of PE was 28.1% and that of renal vein thrombosis 25.0% in the pediatric population with nephrotic syndrome on the basis of our small cohort. DE CTPA has the potential to improve the detection of PE in the pediatric population. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the wave propagation and transient response of an infinite functionally graded plate under a point impact load in thermal environments are studied. The thermal effects and temperature-dependent material properties are taken into account. The temperature field considered is assumed to be a uniform distribution over the plate surface and varies in the thickness direction only. Material properties are assumed to be temperature-dependent, and graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents. Considering the effects of transverse shear deformation and rotary inertia, the governing equations of the wave propagation in the functionally graded plate are derived from Hamilton’s principle. The analytic dispersion relation of the functionally graded plate is obtained by means of integral transforms and a complete discussion of dispersion for the functionally graded plate is given. Using the dispersion relation and integral transforms, exact integral solutions of the functionally graded plate under a point impact load in thermal environments are obtained. The influences of the volume fraction distributions and temperature field on the wave propagation and transient response of functionally graded plates are discussed in detail. The results carried out can be used in the ultrasonic inspection techniques and provide a theoretical basis for engineering applications. [Copyright &y& Elsevier]