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Elucidating changes in the structure and function of plant communities along different elevation ranges will help researchers to analyze the strategies plant communities use in environments and processes influencing niche differentiation. The aims of this paper are to reveal the underlying mechanisms and ecological processes governing the development of subtropical forest ecosystem plant communities. This paper analyzes the forest vegetation of the Wuyi Mountains across the following three elevation ranges: low elevation, mid elevation, and high elevation, spanning from 560 to 2150 m. Twenty and twenty-three dominant tree and shrub layer species, respectively, were identified based on their importance values, and their niches and species associations were further analyzed based on the elevation range. The results showed interspecific associations between tree and shrub species, with the strongest associations observed at mid-elevations. The analysis of niche width and overlap showed that the number of pairs of species with a higher degree of niche overlap decreased with increasing elevation, suggesting that resource use varied at different elevations for both tree and shrub layer species, which may be related to the adaptive capacity of plants at different elevations to the environment and resource use strategies. These findings should contribute to a deeper understanding of the ecological functioning and structural framework of plant communities on Wuyi Mountain. [ABSTRACT FROM AUTHOR]

(1) Background: This research aims to identify candidates for trimodality therapy (TMT) or radical cystectomy (RC) by using a predictive model. (2) Methods: Patients with nonmetastatic muscle-invasive bladder cancer (MIBC) in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled. The clinical data of 2174 eligible patients were extracted and separated into RC and TMT groups. To control for confounding bias, propensity score matching (PSM) was carried out. A nomogram was established via multivariable logistic regression. The area under the receiver operating characteristic curve (AUC) and calibration curves were used to assess the nomogram's prediction capacity. Decision curve analysis (DCA) was carried out to determine the nomogram's clinical applicability. (3) Results: After being processed with PSM, the OS of the RC group was significantly longer compared with the TMT group (p < 0.001). This remarkable capacity for discrimination was exhibited in the training (AUC: 0.717) and validation (AUC: 0.774) sets. The calibration curves suggested acceptable uniformity. Excellent clinical utility was shown in the DCA curve. The RC and RC-Beneficial group survived significantly longer than the RC and TMT-Beneficial group (p < 0.001) or the TMT group (p < 0.001). However, no significant difference was found between the RC and TMT-Beneficial group and the TMT group (p = 0.321). (4) Conclusions: A predictive model with excellent discrimination and clinical application value was established to identify the optimal patients for TMT among nonmetastatic MIBC patients. [ABSTRACT FROM AUTHOR]

Sedimentary facies color is an important paleoclimate indicator, but may be unreliable in thick continental red beds. The Danxia Formation is the landscape strata of the Danxia basin, and its color fluctuates between reddish-brown and reddish-purple vertically. This study examined the ferric oxides characteristics, distribution, and mineral composition of the Danxia Formation using a variety of analytical techniques, including optical microscopy, high-resolution scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and micro-Raman spectroscopy. The results indicate that the reddish-brown mineral is composed primarily of fine hematite with traces of goethite, while the reddish-purple mineral consists solely of fine hematite. These hematites exhibit a particle size range of submicron to micron and display various morphologies, including spherical, flake, and fibrous forms. Goethite particles are needle-shaped and often form star-shaped aggregates containing twins. Whole rock geochemical analysis reveals a strong positive correlation between iron and iron group elements, as well as phosphorus and rare earth elements. The findings suggest that the reddening of the Danxia Formation occurs during diagenesis, with fine hematite forming as a result of the alteration of iron-bearing detrital grains. In addition, vertical color variations in Danxia Formation are not attributable to the paleoclimate records, but rather the result of the differentiation of sediment sources. This study provides a novel viewpoint for examining the coloration of thick continental red beds in other regions. [ABSTRACT FROM AUTHOR]

(1) Purpose: The purpose of this study was to evaluate the prognostic capacity of the pathological N status (pN), lymph node ratio (LNR), and the log odds of positive lymph nodes (LODDS), and to build a prognostic nomogram to predict overall survival (OS) for bladder cancer patients treated by radical cystectomy. (2) Methods: The clinical and pathological characteristics of 10,938 patients with bladder cancer were identified from the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2017. The predictive capacity was assessed by univariate and multivariate Cox regression analyses, the area under the receiver operating characteristic curve (AUC), and C-index. Calibration curves, decision curve analysis (DCA), and risk-grouping were utilized to evaluate the predictive accuracy and discriminative ability of the nomogram. (3) Results: LODDS was an independent risk factor for bladder cancer (all p < 0.001) and demonstrated the highest values of C-index and AUC. The values of AUCs in the training cohort were 0.747, 0.743, and 0.735 for predicting 1-, 3-, and 5-year OS, respectively. Calibration curves and DCA curves suggested the excellent clinical application value of our nomogram. (4) Conclusions: LODDS is a better predictive indicator for bladder cancer patients compared to pN and LNR. The LODDS-incorporated nomogram has excellent accuracy and promising clinical application value for non-metastatic bladder cancer after radical cystectomy. [ABSTRACT FROM AUTHOR]

Continental red beds, widely formed at various geologic timescales, are sedimentary rocks and sediments with red as the main color. Geoscientists have analyzed the geomorphology, paleomagnetism, paleoenvironments, paleontology, energy, and minerals in continental red beds. Despite the agreement that fine-grained hematite is closely related to the color of continental red beds, controversies and problems still exist regarding the micro-mechanism of their formation. As a review, this paper details the composition and color properties of pigmentation in red beds, analyzes the existence and distribution of authigenic hematite, and summarizes the iron sources and the formation of hematite. In addition, we introduce the fading phenomenon observed in continental red beds, including three types of secondary reduction zones: reduction spots, reduction strips, and reduction areas. Lastly, this paper summarizes the evolution of color in continental red beds, emphasizes the relationship between authigenic hematite and the diagenetic environment, and proposes possible research directions for future red bed-related issues. [ABSTRACT FROM AUTHOR]

In many outdoor inductive charging applications, the objects can move quickly, and the environment can change unpredictably. It is therefore difficult to design a fast controller that tracks the change in mutual coupling between the transmitter and receiver. The diminished power delivery to the objects either leads to incomplete charging or prolongs the charging time. In this paper, the concept of a zone impedance matching technique is proposed. This technique pre-matches the transmitter coil to the desired coupling coefficients. Thus, the power transfer capability of the inductive charger can be maintained at a reasonably high level over a long transmission distance and under a wide receiver misalignment. Based on a three-coil inductive power transfer (IPT) system, the proposed concept is practically implemented with a simple control scheme. The proposed IPT system equips a multi-tap transmitter coil to provide flexibility in selecting different numbers of turns in the transmitter coil. The controller senses the currents of the transmitter coil and the repeater coil to determine the zone of impedance to adapt to the change in mutual coupling of the coils. A mathematical analysis is conducted to formulate the design procedures for the proposed system. Under a wide range of distance and misalignment conditions, practical measurement results verified that the proposed system achieves higher power delivery than an ordinary design. [ABSTRACT FROM AUTHOR]

Background: The existing studies on primary bladder lymphoma (PBL) are retrospective analyses based on individual cases or small series studies, and the research on PBL is not unified and in-depth enough at present because of the scarcity of PBL and the lack of relevant literature. This study is designed to develop and validate nomograms for overall survival (OS) and cancer-specific survival (CSS) prediction in patients with PBL. Methods: According to the Surveillance, Epidemiology, and End Results (SEER) database, 405 patients diagnosed with PBL from 1975 to 2016 were collected and randomly assigned to training (n = 283) and validation (n = 122) cohort. After the multivariable Cox regression, the OS and CSS nomograms were developed. The discrimination, calibration and clinical usefulness of the nomograms were assessed and validated, respectively, by the training and validation cohort. Furthermore, all of the patients were reclassified into high- and low-risk groups and their survival were compared through Kaplan-Meier method and log-rank test. Results: Age, subtype, Ann Arbor stage, radiation and chemotherapy were identified as independent prognostic factors for OS and age, sex, and subtype for CSS, then corresponding nomograms predicting the 3- and 5-year survival were constructed. The presented nomograms demonstrated good discrimination and calibration, which the C-index in the training and validation cohort were 0.744 (95% confidence interval [CI], 0.705–0.783) and 0.675 (95% CI, 0.603–0.747) for OS nomogram and 0.692 (95% CI, 0.632–0.752) and 0.646 (95% CI, 0.549–0.743) for CSS nomogram, respectively. Furthermore, the nomograms can be used to effectively distinguish Patients with PBL at high risk of death. The clinical usefulness of the nomograms was visually displayed by decision curve analysis. Conclusion: We updated the baseline characteristics of patients with PBL and constructed OS and CSS nomograms to predict their 3- and 5-year survival. Using these nomograms, it would be convenient to individually predict the prognosis of patients with PBL and provide guidance for clinical treatment. [ABSTRACT FROM AUTHOR]

Aramid fiber-reinforced plastic (AFRP) composites are widely used in aerospace, rail transit, marine and military industries, due to their high specific strength, high impact resistance, fatigue resistance and excellent designable properties. In order to meet different application requirements, cutting processes need to be carried out, such as window opening, edge cutting and slit cutting. However, the characteristics of high tensile strength and toughness, low interlaminar strength, non-uniformity and anisotropy make AFRP composites a difficult-to-machine material. They are prone to produce rough cutting surfaces and cutting damages including burr, wire drawing, delamination, resin burn, material flanging, etc. To solve this problem, the ultra-thin diamond dicing blade was used for high-speed cutting of AFRP composites in sub-fiber scale in this research. The influence of process parameters on cutting force, cutting temperature, maximum spindle current, tool wear and cutting surface quality were investigated by establishing the cutting force model, L16(45) orthogonal experiment, single factor experiment, range analysis and variance analysis. The theoretical and experimental results show that cutting AFRP composites with ultra-thin diamond dicing blade can obtain smooth surfaces without common cutting damages. When the cutting speed is 91.11 m/s (spindle speed n = 30,000 r/min), the cutting depth is 0.2 mm and the feed speed is 5 mm/s, the surface roughness Ra can be as low as 32 nm, which realize the precision cutting of AFRP composites. [ABSTRACT FROM AUTHOR]

This paper presents an innovative method for high-speed micro-cutting of carbon fiber reinforced plastics (CFRP). It employs a diamond dicing blade for micromachining applications, with a thickness of about 200 μm and rotational speeds up to 30,000 rpm so as to meet the low-damage surface integrity requirements. The process parameters, cutting damage, surface roughness, and the spindle vibration were thoroughly investigated to evaluate and validate the method. The results indicate that a high cutting speed up to 76 m/s not only remarkably increases the rigidity of an ultra-thin dicing blade, but also decreases the cutting depth per diamond grit to below 10 nm, both of which are very conducive to obtaining a very fine machined surface of about Ra 0.025 μm, with no obvious damage, such as delamination, burrs, and fiber pull out. The serious spindle vibration limits the rotational speed to increase further, and the rotational speed of 25,000 rpm achieves the best fine machined surface. Furthermore, unlike most research results of the drilling and milling method, the proposed micro-cutting method obtains the maximum cutting current and surface roughness when cutting at 0° fiber orientation, while obtaining a minimum cutting current and surface roughness when cutting at 90° fiber orientation. The metal-bonded dicing blade achieves smaller surface roughness than the resin-bonded dicing blade. This paper also discusses the cutting mechanism by investigating the morphology of the machined surface and concludes that the micro breakage and plastic-flow in local regions of fibers and resin are the main material removal mechanisms for dicing CFRP composites with a diamond abrasive blade. [ABSTRACT FROM AUTHOR]