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• The CFRCs honeycomb sandwich structures are fabricated integrally by 3D printing technique. • The damage types at each stage of the flatwise compression process of 3D printed CFRCs honeycomb sandwich structures are successfully characterized. • A 3D printing method for CFRCs honeycomb sandwich structures with multilayer sandwich and core/panel variable printing thickness is proposed. • The compressive strength and energy absorption capacity of multilayer CFRCs honeycomb sandwich structures have obvious advantages. Continuous fiber reinforced composites (CFRCs) 3D printing technology has the advantage of integrated fabricating for honeycomb sandwich structures, the load-bearing capacity of the fabricated honeycomb sandwich structures still needs to be investigated and improved. This study aims to reveal compression failure modes of 3D printed CFRCs honeycomb sandwich structures with various internal configurations by conducting flatwise compression tests. The deviations of single-layer CFRCs honeycomb cores with different core sizes and core heights and their impacts on the compression failure process were analyzed. A 3D printing method with multilayer cores and core/panel variable printing thickness was proposed, and the effects of multilayer core structure and different core printing parameters on the compressive properties of honeycomb sandwich structures were investigated. The results showed that interlayer cracking caused by core buckling deformation was the leading cause of failure of 3D printed CFRCs honeycomb sandwich structures when subjected to compression. The core buckling deformation could be suppressed by printing multilayer cores and using low core printing thickness, and the compression strength and specific energy absorption of the sandwich structures reached 38.1 MPa and 25.4 kJ/kg, respectively. This study provides guidance for the customization of the 3D printing process of CFRCs honeycomb sandwich structures. [Display omitted] [ABSTRACT FROM AUTHOR]

Cuproptosis is a newly identified form of cell death driven by copper. Recently, the role of copper and copper triggered cell death in the pathogenesis of cancers have attracted attentions. Cuproptosis has garnered enormous interest in cancer research communities because of its great potential for cancer therapy. Copper-based treatment exerts an inhibiting role in tumor growth and may open the door for the treatment of chemotherapy-insensitive tumors. In this review, we provide a critical analysis on copper homeostasis and the role of copper dysregulation in the development and progression of cancers. Then the core molecular mechanisms of cuproptosis and its role in cancer is discussed, followed by summarizing the current understanding of copper-based agents (copper chelators, copper ionophores, and copper complexes-based dynamic therapy) for cancer treatment. Additionally, we summarize the emerging data on copper complexes-based agents and copper ionophores to subdue tumor chemotherapy resistance in different types of cancers. We also review the small-molecule compounds and nanoparticles (NPs) that may kill cancer cells by inducing cuproptosis, which will shed new light on the development of anticancer drugs through inducing cuproptosis in the future. Finally, the important concepts and pressing questions of cuproptosis in future research that should be focused on were discussed. This review article suggests that targeting cuproptosis could be a novel antitumor therapy and treatment strategy to overcome cancer drug resistance. [ABSTRACT FROM AUTHOR]

• Hypertrophic olivary degeneration (HOD) is a rare form of transneuronal degeneration of the inferior olivary nucleus. • We provide a comprehensive review of the literatures focusing on etiology. • The present paper contribute to a better understanding of HOD clinical characteristic, which will be helpful for neurologists and radiologists. Hypertrophic olivary degeneration (HOD) is a rare form of trans-synaptic degeneration characterized by hypertrophy of the inferior olivary nucleus situated in the olivary body, part of the medulla oblongata, representing a major source of input to the cerebellum. HOD typically results from focal lesions interrupting connections from the inferior olive within the dentato-rubro-olivary pathway (DROP), a region also known as the Guillain-Mollaret triangle (GMT) (red nucleus, inferior olivary nucleus, and contralateral dentate nucleus). Clinically, HOD presents classically as palatal tremor and can include dentatorubral tremor and/or ocular myoclonus. Oppenheim first described the enlargement of the ION in his post-mortem study. Since then, a limited number of cases have been reported in the literatures. Thus, we intended to describe the definition, pathophysiology, clinical features, radiological features, diagnosis, and current management of HOD. We provide a comprehensive review of HOD focusing on etiology. The present review may lead to a better understanding of HOD clinical characteristic with the goal of contributing to existing knowledge of this rare disease. [ABSTRACT FROM AUTHOR]

Abstract This study proposes a two-component (surface and volume) C-band polarimetric decomposition to retrieve soil moisture over agricultural fields covered by different crop types. RADARSAT-2 data analysis shows that vegetation attenuation on the surface scattering component is stronger for the narrow-leaf (wheat) than broad-leaf crops (canola, corn and soybean). Thus, the vegetation attenuation factor is integrated into the proposed C-band polarimetric decomposition to better account for soil contribution over the whole crop phenological season. After removing the volume scattering component from the full coherency matrix, the surface scattering component was simulated by the Oh soil scattering model, instead of conventional Bragg or X-Bragg model, which is not physically valid at C-band due to limited roughness constraint condition. The proposed retrieval algorithm was applied to the RADARSAT-2 time series acquired during the Soil Moisture Active Passive Validation Experiment in 2012 (SMAPVEX12). Results indicate that during the crop growth, the volume scattering power of wheat shows weak temporal variation, while it increases for corn, soybean and canola. The sensitivity of the ground scattering component to soil moisture is enhanced due to the removal of the volume scattering from the full signature. The retrieved soil moisture was validated using the soil moisture ground measurements during the SMAPVEX12. The validations indicate correlation coefficients from 0.63 to 0.76, and RMSEs from 0.058 to 0.074 m3/m3 for the entire phenological period of SMAPVEX12 campaign. The negligible dihedral scattering component (1.6–9.2%) at C-band greatly reduces the complexity of the soil moisture retrieval from the ground component. Highlights • A two-component C-band model-based polarimetric decomposition is developed. • Surface scattering component is simulated by Oh model instead of X-Bragg model. • A vegetation attenuation factor is included in the surface scattering component. • Soil moisture is retrieved for the entire phenological stages during SMAPVEX12. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke (AIS) is highly prevalent in patients with infective endocarditis (IE) and associated with high rates of death and disability. IE presenting as an acute ischemic stroke, especially recurrent concurrence of acute anterior and posterior circulation infarct, has rarely been reported. Herein, we report a case study of a 60-year-old man with a history of aortic valve replacement and was under warfarin, presented with recurrent acute ischemic stroke which was found to have no vegetation secondary to infective endocarditis caused by Streptococcus constellatus as the embolic source. This is the first case report of recurrent ischemic stroke secondary to IE without vegetation caused by Streptococcus constellatus involving concurrence of acute anterior and posterior circulation. We also then systematically analyze the cases with IE initially presenting as AIS reported in the literature to establish possible demographic, clinical, laboratory patterns, and prognostic features of these cases. [ABSTRACT FROM AUTHOR]

Geopolymers are a new class of green high-strength aluminosilicate materials, which generally maintain an amorphous structure due to the limitations related to their chemical compositions and reaction conditions but possess the ability to form molecular sieves. In this work, the in-situ transformation of geopolymers into self-supporting NaX zeolite monoliths of relatively large sizes was examined under hydrothermal conditions and various parameters of the synthesis process were optimized. The obtained results indicated that the optimal transformation conditions for geopolymers with a Si/Al ratio of 4.0 are as follows: precursors composed of metakaolin and modified industrial sodium silicate with a Na 2 O/SiO 2 molar ratio of 1.0, H 2 O/Na 2 O molar ratio of 70, hydrothermal synthesis time of 18 h and a temperature of 90 °C. According to the obtained X-ray diffraction (XRD) data, the synthesized NaX Monoliths exhibited characteristic reflections consistent with those of standard NaX zeolites and possessed high degrees of crystallinity, while scanning electron microscopy revealed that the produced molecular sieves exhibited well-defined morphology. In addition, the zeolitic monoliths exhibited excellent compressive strength for potential practical applications. [ABSTRACT FROM AUTHOR]

This study investigates and compares the potential of three model-based polarimetric decompositions, namely those developed by Freeman-Durden (1998), Hajnsek et al. (2009) and An et al. (2010), for soil moisture retrieval over agricultural fields covered by several crops. The volume scattering component was first removed from the full coherency matrix. Then, in order to reduce the effect of the incidence angle on the retrieval results, a normalization process at a reference incidence angle was conducted for the first time, on the dominant surface or dihedral scattering component from which the soil moisture was retrieved. The time series of Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) data and the ground measurements of soil and vegetation characteristics collected during the Soil Moisture Active Passive (SMAP) Validation Experiment in 2012 (SMAPVEX12) were used to compare the three decomposition methods with respect to the scattering mechanisms and the soil moisture retrieval performances. The results show that the performance of each decomposition method for soil moisture retrieval depends on the crop types and the crop phenological stages. Indeed, Freeman-Durden model provided the best results for corn and wheat, Hajnsek decomposition performed well for canola, while better results were obtained for soybean using An decomposition. At the early growth stage, both the surface and dihedral scattering components contributed to retrieve the soil moisture, while at a later crop development, the surface scattering component is almost the only scattering mechanism from which soil moisture was retrieved. Thus, the best performance for soil moisture retrieval was obtained a) at the early crop development stage from Hajnsek decomposition which better integrated the dihedral component and b) at a later growth stage from An decomposition which enhanced the surface scattering. Finally, an overall soil moisture underestimation with RMSE of 0.06–0.11 m 3 /m 3 was observed from the three decompositions, and the highest retrieval rate of 33%–39% was obtained from An decomposition as a result of the enhanced surface scattering. [ABSTRACT FROM AUTHOR]

This study investigates the different performances between Compact-Polarimetric (CP) and Full-Polarimetric (FP) SAR to retrieve multiple crop growth parameters including Vegetation Water Content (VWC), Leaf Area Index (LAI), height, and dry biomass. The objective is to study at which conditions the CP SAR can obtain comparable retrieval accuracy as FP SAR for specific crop types and growth descriptors. Polarimetric decompositions were used to extract CP and FP explanatory variables to quantify crop growth status. Then, the sensitivities of CP and FP variables to different crop descriptors were analyzed, revealing higher sensitivity to height than LAI, VWC, and dry biomass. In order to reduce the information redundancy of sets of CP and FP SAR variables, Partial Least Square (PLS) approach was used to develop new orthogonal SAR parameters, while Step-Wise Regression (SWR) was used to determine the optimal SAR parameters, followed by retrievals of multiple crop growth descriptors using the developed estimators. Validated by the ground measurements, the retrieval performances are found to be highly dependent on polarimetry dimension (CP or FP), crop types, and targeted crop descriptors. With crop growth and enhanced depolarization effects, the CP SAR can capture the increasing volume power and decreasing surface power but at a lower rate than FP SAR. The m - δ and m - χ decompositions provide similar scattering components which differ from the Random Volume Over Ground (RVOG) decomposition. The third Stokes parameter g 3 of the CP SAR data that indicates the strength of the circular polarization component is a common important parameter to infer the multiple crop parameters of interest. In agreement with the sensitivity analysis, better retrieval accuracies were obtained for height and dry biomass than VWC and LAI. For short vegetation such as soybean, full polarimetry is required to obtain the estimates of all four crop growth descriptors. On the contrary, for tall crop growth parameters, such as canola (height and dry biomass), corn (height, VWC, dry biomass), and wheat (LAI, VWC, dry biomass), the CP SAR features can provide comparable robust retrieval accuracy as the FP SAR features. This study deepens our insights into the CP SAR of the RADARSAT Constellation Mission (RCM) to timely monitor crop growth and health status. • Analyze different retrieval performances of Compact- and Full-Polarimetric SAR. • m - δ , m - χ , and RVOG decompositions were evaluated to monitor crop growth. • Third stokes parameter g 3 was effective to estimate multiple crop parameters. • Retrieval of crop height was better than LAI, biomass, and vegetation water content. • CP and FP SAR were suitable for tall (canola, corn, and wheat) and short crops (soybean), respectively. [ABSTRACT FROM AUTHOR]

Development of resistance to chemotherapy in cancer continues to be a major challenge in cancer management. Ferroptosis, a unique type of cell death, is mechanistically and morphologically different from other forms of cell death. Ferroptosis plays a pivotal role in inhibiting tumour growth and has presented new opportunities for treatment of chemotherapy-insensitive tumours in recent years. Emerging studies have suggested that ferroptosis can regulate the therapeutic responses of tumours. Accumulating evidence supports ferroptosis as a potential target for chemotherapy resistance. Pharmacological induction of ferroptosis could reverse drug resistance in tumours. In this review article, we first discuss the key principles of chemotherapeutic resistance in cancer. We then provide a brief overview of the core mechanisms of ferroptosis in cancer chemotherapeutic drug resistance. Finally, we summarise the emerging data that supports the fact that chemotherapy resistance in different types of cancers could be subdued by pharmacologically inducing ferroptosis. This review article suggests that pharmacological induction of ferroptosis by bioactive compounds (ferroptosis inducers) could overcome chemotherapeutic drug resistance. This article also highlights some promising therapeutic avenues that could be used to overcome chemotherapeutic drug resistance in cancer. [ABSTRACT FROM AUTHOR]

The detoxification and immobilization of Cr(VI) using metakaolin-based geopolymer coupled with ferrous chloride was solved successfully. Adding potassium dichromate and ferrous chloride in the base colloid formed by mixing metakaolin and the alkaline activator, Cr(VI)-contaminated metakaolin-based geopolymer was prepared, whose compressive strength was more than 30 MPa. The optimized capacity of chromium in the geopolymer was 0.8 wt.% with an optimized Fe 2+ /Cr(VI) mole ratio of 4:1, which ensured a low leached chromium concentration below 5 mg/L. This product was mainly amorphous except by-product sodium chloride. According to XRD, SEM and XPS, the mechanism of Cr detoxification/immobilization was speculated and explained. In the colloid, the negatively charged [AlO 4 ] was first formed because of the geopolymerization, and at the same time, Cr(VI) was reduced to Cr 3+ under the participation of Fe 2+ . Then, Cr 3+ was attracted by [AlO 4 ] due to the electrostatic attraction and stabilized in geopolymerical matrices. Therefore, the immobilization of Cr(VI) in geopolymer contained a redox and a fixation process. This method is expected to be used for the disposal of Cr(VI)-contaminated solid wastes. [ABSTRACT FROM AUTHOR]

Our recent study demonstrated that pinocembrin (PB), the most abundant flavonoid in propolis, has neuroprotective effect against 1-methyl-4-phenylpyridinium (MPP + )-induced SH-SY5Y neurotoxicity. However, the mechanism as how PB can induce neuroprotection is not known. In the present study, we demonstrate here that PB increased heme oxygenase-1 (HO-1) expression, which conferred protection against MPP + -induced cytotoxicity, because the inhibitor of HO-1 zinc protoporphyrin-IX attenuated the neuroprotection of PB. PB induced the phosphorylation of ERK1/2, and its cytoprotective effect was abolished by ERK1/2 inhibitors. Meanwhile, we have shown that MPP + induce the expression in a concentration-dependent manner in SH-SY5Y cells, which was further enhanced by PB. Taken together, the results suggest that PB enhances HO-1 expression to suppress MPP + -induced oxidative damage via ERK1/2 signaling pathways. These results revealed the mechanisms of PB enhances HO-1 expression, and contribute to shed some light on the mechanisms whereby PB inhibits the MPP + -induced neurotoxicity. These data indicated that PB might provide a valuable therapeutic strategy for the treatment of PD. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To assess the efficacy and safety of istradefylline as an adjunct to levodopa in patients with Parkinson''s Disease (PD). Methods: In this study, we searched the Cochrane Library, MEDLINE, Embase, China Academic Journal Full-text Database (CNKI), China Biomedical Literature Database (CBM), Chinese Scientific Journals Database (VIP), and Wanfang Database. The quality of included studies was strictly evaluated. Data analyses were performed by the Cochrane Collaboration''s RevMan5.0 software. Results: Five randomized controlled trials (RCTs) were included. The result showed a significant reduction of the awake time per day spent in the OFF state and improvement of the Unified Parkinson''s Disease Rating Scale (UPDRS) Part III in the ON state when receiving istradefylline compared with patients receiving placebo. There was no significant difference between the istradefylline 20mg and the istradefylline 40mg groups in the UPDRS Part III in the ON state (WMD=1.27, 95% CI [−0.40, 2.95]). The results showed significant differences in dyskinesia (RR=1.63, 95% CI [1.16, 2.29]) compared to istradefylline 40mg with placebo. There was no significant statistical difference with regard to other adverse events. Conclusions: The present study showed that istradefylline is safe and effective as an adjunct to levodopa in patients with PD. Future large-scale, higher-quality, long-treatment, and placebo-controlled trials are needed. [Copyright &y& Elsevier]

Abstract: Amyloid β-peptide (Aβ) has been implicated in the pathogenesis of AD. It can cause cell death in AD by evoking a cascade of oxidative damage to neurons. So antioxidant compounds may throw a light on the treatment of AD. In the present study, we investigated the protective effect of acteoside (AS), an antioxidative phenylethanoid glycoside, on Aβ25–35-induced SH-SY5Y cell injury. Exposure of cells to 25 μM Aβ25–35 for 24 h caused viability loss, apoptotic increase and reactive oxygen species (ROS) increase, pre-treatment with acteoside for 1.5 h significantly reduced the viability loss, apoptotic rate and attenuated Aβ-mediated ROS production. In addition, AS strikingly inhibited Aβ25–35-induced mitochondrial dysfunctions, including lowered membrane potential, increased Bax/Bcl-2 ratio, cytochrome c release and the cleavage of caspase-3. Taken together, these results indicated that acteoside could protect SH-SY5Y cells against β-amyloid-induced cell injury by the attenuating ROS production and the modulating apoptotic signal pathway through Bcl-2 family, cytochrome c, and caspase-3. [Copyright &y& Elsevier]

This paper investigates the soil moisture retrievals over Tibetan Plateau using multi-temporal ALOS2-PALSAR2 data acquired in ScanSAR mode, in contrary to the commonly used StripMap SAR imaging mode. Considering the dual-polarimetry with limited observables, the surface roughness parameters such as the RMS height and auto-correlation length are first estimated by optimizing the semi-empirical Oh2004 model applied to the ALOS2 data acquired under bare soil condition. The vegetation water content corresponding to each ALOS2 acquisition time is derived from an empirical model applied to the temporally interpolated MODIS NDVI data. Then, the obtained roughness and vegetation optical depth are substituted into the Water Cloud Model which we modified by adding a double-bounce component according to the L-band scattering processes to retrieve the effective scattering albedo and soil moisture. The results show that the optimized surface RMS height and the associated slope are negatively related to a dual-angular radar index ΔHH, indicating the feasibility to optimize the relatively stable surface roughness parameters before retrieving the soil moisture dynamics. The obtained vegetation optical depth which is cross-validated against a normalized cross-polarized radar descriptor indicates a significant increase from May to August, in response to the vegetation phenological growth. Furthermore, the time-variable scattering albedo is less than 0.08, and slightly increases with the vegetation development. By accounting for the double-bounce component, the retrieved soil moisture better agrees with the ground measurements with R = 0.89 and RMSE = 0.058 m3/m3, but exhibits an overestimation issue for the soil moisture higher than 0.35 m3/m3 due to the saturation of SAR signal and the relatively strong vegetation cover. A positive correspondence (R = 0.81) between the retrieved soil moisture and the interpolated NDVI was found, verifying their close coupling in the soil-vegetation system. This study deepens the insights in the potential integration between the optical and L-band microwave observations to retrieve soil moisture over vegetated area. • ALOS2 data acquired at ScanSAR mode are investigated to retrieve soil moisture. • Microwave and optical data are coupled in the retrieval process. • Water Cloud Model is calibrated by adding a double-bounce scattering component. • Three-component is better than two-component decomposition for soil moisture retrieval. [ABSTRACT FROM AUTHOR]