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Background: With increasing detection of small renal masses and accumulating evidence that nephron sparing surgery (NSS) could achieve oncological equivalence and functional superiority compared with radical nephrectomy (RN), NSS has become first‐line therapy for some patients with localized renal masses. Objective: This study aims to review the publications in the kidney neoplasm and NSS field, exploring the research hotspots. Method: Kidney neoplasm and NSS related publications before July 3th 2023 were obtained from the Web of Science Core Collection database. We then used bibliometric analysis to conduct performance analysis, citation analysis and co‐citation network of publications, together with keyword co‐occurrence analysis. Results: Seven thousand five hundred and sixty‐four documents were finally retrieved, and the annual publications increased exponentially. The most productive authors were "KAOUK JH" and "GILL IS", while USA, and 12 American affiliations such as CLEVELAND CLINIC FOUNDATION and MAYO CLINIC were far leading in this field. Journal of Urology and European Urology were journals with the highest citations and h‐index. Discussion: Through literature reviewing plus co‐occurrence and clustering analysis, the therapeutic effects of partial nephrectomy (PN) versus RN on patients with localized renal cell carcinoma, different operative approaches of PN, and conservative NSS methods were deemed as the most focused topics. Conclusion: Three aspects were the most important hotspots in this field. Firstly, how to provide the optimal management choices for different patients. Secondly, therapeutic effects of different management options and surgical techniques needed more prospective and randomized studies. Finally, more novel technologies and surgical techniques were required. [ABSTRACT FROM AUTHOR]

Purpose: To explore the diagnostic value of intralesional and perilesional radiomics based on multimodal ultrasound (US) images in predicting the malignant ACR TIRADS 4 thyroid nodules (TNs). Methods: A total of 297 cases of TNs in patients who underwent preoperative thyroid grayscale US and shear wave elastography (STE) were enrolled (training cohort: n = 150, internal validation cohort: n = 77, external validation cohort: n = 70). Regions of interests (ROIs) were delineated on grayscale US images and STE images, and then an isotropic expansion of 1.0, 1.5, 2.0, 2.5, and 3.0 mm was applied. Predictive models were established using recursive feature elimination‐support vector machines (RFE‐SVM) based on radiomics features calculated by random forest. Results: The perilesional ROI1.5mm expansion achieved the highest area under curve (AUC) (AUC: 0.753 for grayscale US, 0.728 for STE; 95% confidence interval (CI): 0.664–0.743, 0.684–0.739, respectively). The joint model had the highest AUC values of 0.936 in the training dataset, 0.926 in internal dataset, and 0.893 in external dataset. The calibration curve showed good consistency and the decision curve indicated a greater clinical net benefit of the joint model. Conclusion: Joint model containing perilesional radiomics (1.5 mm) had significant value in predicting the malignant ACR TIRADS 4 TNs. [ABSTRACT FROM AUTHOR]

We propose a new test to investigate the conditional mean dependence between a response variable and the corresponding covariates in the high‐dimensional regimes. The test statistic is an extreme‐type one built on the nonparametric method. The limiting null distribution of the proposed extreme type statistic under a mild mixing condition is established. Moreover, to make the test more powerful in general structures we propose a more general test statistic and develop its asymptotic properties. The power analysis of both methods is also considered. In real data analysis, we also propose a new way to conduct the feature screening based on our results. To evaluate the performance of our estimators and other methods, extensive simulations are conducted. [ABSTRACT FROM AUTHOR]

Improving interfacial kinetics is the key to realizing extreme fast charging (XFC) of graphite‐based potassium ion batteries (PIBs). The electrolyte engineering is commonly used for solid electrolyte interphase (SEI) design. However, this strategy adjusts both ion solvation structure and (de)solvation kinetics simultaneously, thus making it difficult to explicitly reveal the linkage between SEI properties and interfacial kinetics. Herein, the content of inorganic species in preformed SEI on graphite surface is precisely regulated and uncovered its critical role in improving the interfacial kinetics. The charge transfer kinetics on graphite/electrolyte interphase is found to be the rate limitation step upon XFC. Meanwhile, the increased inorganic species in SEI plays a decisive role in optimizing the charge transfer rather than the kinetics of naked K+ crossing SEI. Through unlocking the anodic charge transfer limitation with ultra‐inorganic rich SEI, the graphite//Prussian blue analogs full cells achieve a superior XFC ability (13 min charge to 80%) with a specific capacity of 103 mAh g−1 at 5 C. This work provides a fundamental understanding of the relationship between SEI properties and interfacial kinetics during XFC, which enables the rational design of SEI chemistry for fast‐charging PIBs. [ABSTRACT FROM AUTHOR]

Organic electrode materials are promising for next‐generation energy storage materials due to their environmental friendliness and sustainable renewability. However, problems such as their high solubility in electrolytes and low intrinsic conductivity have always plagued their further application. Polymerization to form conjugated organic polymers can not only inhibit the dissolution of organic electrodes in the electrolyte, but also enhance the intrinsic conductivity of organic molecules. Herein, we synthesized a new conjugated organic polymer (COPs) COP500‐CuT2TP (poly [5,10,15,20‐tetra(2,2′‐bithiophen‐5‐yl) porphyrinato] copper (II)) by electrochemical polymerization method. Due to the self‐exfoliation behavior, the porphyrin cathode exhibited a reversible discharge capacity of 420 mAh g−1, and a high specific energy of 900 Wh Kg−1 with a first coulombic efficiency of 96 % at 100 mA g−1. Excellent cycling stability up to 8000 cycles without capacity loss was achieved even at a high current density of 5 A g−1. This highly conjugated structure promotes COP500‐CuT2TP combined high energy density, high power density, and good cycling stability, which would open new opportunity for the designable and versatile organic electrodes for electrochemical energy storage. [ABSTRACT FROM AUTHOR]

At present, in order to overcome electromagnetic interference and prevent electromagnetic harm, the research of new and efficient electromagnetic wave absorbing materials has become the research focus in the field of materials science. The one-dimensional structure can promote the impedance matching and attenuation characteristics of the absorbing materials. Electrospinning, as an effective method to prepare nanofibers with high length-diameter ratio, has been widely concerned because it is suitable for structural design of various materials. In this paper, the research progress and absorption properties of nano-fiber materials prepared by electrospinning combined with different processes are introduced. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (KIBs) are promising energy storage devices owing to the close redox potential of potassium (K) to lithium and rich abundance of K resource, thus promoting the exploration of efficient cathode materials for K‐ions storage. Fe‐based Prussian blue analogues (KFeHCF) are promising cathode materials for KIBs due to their combined advantages in low cost and high energy density. However, the rapid capacity decay induced by unstable cathode electrolyte interphase (CEI) and dissolution of transition metal ions leads to limited lifespans (e.g., hundreds of cycles) of K∥KFeHCF batteries. Incorporating additives into electrolytes is an economical and effective way to construct robust CEI for high‐performance KIBs. Herein, a multifunctional electrolyte additive, potassium selenocyanate (KSeCN), is introduced to effectively construct stable, homogeneous and conductive CEI films, which leads to the inhibition of Fe dissolution and stabilization of KFeHCF structure during cycling. With 0.5 wt% of KSeCN in conventional carbonated electrolyte, the K∥KFeHCF battery exhibits promoted cycling performance with a capacity retention rate of 87% after 500 cycles at 4.5 V cutoff voltage. This finding provides a new paradigm for developing and designing potassium‐ion battery electrolytes. [ABSTRACT FROM AUTHOR]

Owing to outstanding performances, nickel‐based electrocatalysts are commonly used in electrochemical alcohol oxidation reactions (AORs), and the active phase is usually vacancy‐rich nickel oxide/hydroxide (NiOxHy) species. However, researchers are not aware of the catalytic role of atom vacancy in AORs. Here, we study vacancy‐induced catalytic mechanisms for AORs on NiOxHy species. As to AORs on oxygen‐vacancy‐poor β‐Ni(OH)2, the only redox mediator is electrooxidation‐induced electrophilic lattice oxygen species, which can only catalyze the dehydrogenation process (e.g. the electrooxidation of primary alcohol to carboxylic acid) instead of the C−C bond cleavage. Hence, vicinal diol electrooxidation reaction involving the C−C bond cleavage is not feasible with oxygen‐vacancy‐poor β‐Ni(OH)2. Only through oxygen vacancy‐induced adsorbed oxygen‐mediated mechanism, can oxygen‐vacancy‐rich NiOxHy species catalyze the electrooxidation of vicinal diol to carboxylic acid and formic acid accompanied with the C−C bond cleavage. Crucially, we examine how vacancies and vacancy‐induced catalytic mechanisms work during AORs on NiOxHy species. [ABSTRACT FROM AUTHOR]

The sluggish kinetics in traditional graphite anode greatly limits its fast‐charging capability, which is critically important for commercialization of potassium ion batteries (PIBs). Hard carbon possesses randomly oriented pseudo‐graphitic crystallites, enabling homogeneous reaction current and superior rate performance. Herein, a series of hybrid anodes with different hard carbon/graphite ratios are prepared by uniformly mixing graphite and hard carbon with ball‐milling. Comprehensive experimental results in combination phase‐field simulations reveal that the hybrid anode possesses a homogeneous reaction current and an intriguing potential difference between K+‐adsorbed hard carbon and non‐potassiated graphite. The homogeneous reaction current in the hybrid anode promotes sufficient utilization of electrode material, leading to an increase in the reversible capacity. The present potential difference between K+‐adsorbed hard carbon and non‐potassiated graphite provides an additional electric field force that facilitates the diffusion of K+ from hard carbon into the nearest neighbor graphite. All these together, emphasize the synergistic effects between hard carbon and graphite in hybrid anodes toward satisfactory rate and cycling performance. The hybrid strategy proposed here is compatible with the commercial battery manufacturing, offering a practical pathway for the development of high‐performance PIBs. [ABSTRACT FROM AUTHOR]

A rhodium(III)‐catalyzed oxidative cyclization of chalcones with internal alkynes is reported, generating biologically important 3,3‐disubstituted 1‐indanones along with reusable aromatic aldehydes. This transformation features unique (4+1) reaction mode, excellent regioselectivity in alkyne insertion, broad substrate scope, allows for the construction of quaternary carbon centers, and is scalable. Steric hindrance from substrate and ligand probably controls the chemoselectivity of this carbocyclization. Importantly, this discovery enables a practical two‐step protocol switching the overall reaction of acetophenones with internal alkynes from a (3+2) to a (4+1) annulation. [ABSTRACT FROM AUTHOR]

Cover crops have been reported as one of the most effective practices to increase soil organic carbon (SOC) for agroecosystems. Impacts of cover crops on SOC change vary depending on soil properties, climate, and management practices, but it remains unclear how these control factors affect SOC benefits from cover crops, as well as which management practices can maximize SOC benefits. To address these questions, we used an advanced process‐based agroecosystem model, ecosys, to assess the impacts of winter cover cropping on SOC accumulation under different environmental and management conditions. We aimed to answer the following questions: (1) To what extent do cover crops benefit SOC accumulation, and how do SOC benefits from cover crops vary with different factors (i.e., initial soil properties, cover crop types, climate during the cover crop growth period, and cover crop planting and terminating time)? (2) How can we enhance SOC benefits from cover crops under different cover crop management options? Specifically, we first calibrated and validated the ecosys model at two long‐term field experiment sites with SOC measurements in Illinois. We then applied the ecosys model to six cover crop field experiment sites spanning across Illinois to assess the impacts of different factors on SOC accumulation. Our modeling results revealed the following findings: (1) Growing cover crops can bring SOC benefits by 0.33 ± 0.06 MgC ha−1 year−1 in six cover crop field experiment sites across Illinois, and the SOC benefits are species specific to legume and non‐legume cover crops. (2) Initial SOC stocks and clay contents had overall small influences on SOC benefits from cover crops. During the cover crop growth period (i.e., winter and spring in the US Midwest), high temperature increased SOC benefits from cover crops, while the impacts from larger precipitation on SOC benefits varied field by field. (3) The SOC benefits from cover crops can be maximized by optimizing cover crop management practices (e.g., selecting cover crop types and controlling cover crop growth period) for the US Midwestern maize–soybean rotation system. Finally, we discussed the economic and policy implications of adopting cover crops in the US Midwest, including that current economic incentives to grow cover crops may not be sufficient to cover costs. This study systematically assessed cover crop impacts for SOC change in the US Midwest context, while also demonstrating that the ecosys model, with rigorous validation using field experiment data, can be an effective tool to guide the adaptive management of cover crops and quantify SOC benefits from cover crops. The study thus provides practical tools and insights for practitioners and policy‐makers to design cover crop related government agricultural policies and incentive programs for farmers and agri‐food related industries. [ABSTRACT FROM AUTHOR]

Estimating irrigation water use accurately is critical for sustainable irrigation and studying terrestrial water cycle in irrigated croplands. However, irrigation is not monitored in most places, and current estimations of irrigation water use has coarse spatial and/or temporal resolutions. This study aims to estimate irrigation water use at the daily and field scale through the proposed model‐data fusion framework, which is achieved by particle filtering with two configurations (concurrent, CON, and sequential, SEQ) by assimilating satellite‐based evapotranspiration (ET) observations into an advanced agroecosystem model, ecosys. Two types of experiments using synthetic and real ET observations were conducted to study the efficacy of the proposed framework for estimating irrigation water use at the irrigated fields in eastern and western Nebraska, United States. The experiments using synthetic ET observations indicated that, for two major sources of uncertainties of ET difference between observations and model simulations, which are bias and noise, noise had larger impacts on degrading the estimation performance of irrigation water use than bias. For the experiments using real ET observations, monthly and annual estimations of irrigation water use matched well with farmer irrigation records, with Pearson correlation coefficient (r) around 0.80 and 0.50, respectively. Although detecting daily irrigation records was very challenging, our method still gave a good performance with RMSE, BIAS, and r around 2.90, 0.03, and 0.4 mm/d, respectively. Our proposed model‐data fusion framework for estimating irrigation water use at high spatio‐temporal resolution could contribute to regional water management, sustainable irrigation, and better tracking terrestrial water cycle. Key Points: Combining remotely sensed evapotranspiration (ET) and an agroecosystem model is effective to estimate irrigation water use at daily and field scaleFor two sources of ET uncertainties, noise has larger impacts on degrading the estimation performance of irrigation water use than biasRemotely sensed ET observations and ET simulations from ecosys with high accuracy can improve the estimations of irrigation water use [ABSTRACT FROM AUTHOR]

Controlling electrode/electrolyte interfacial chemistry is critically important for improved K+ storage, but the influences of binder chemistry on electrolyte decomposition and interfacial properties are still poorly understood. Herein, sodium carboxymethyl cellulose (CMC)‐based, and polyvinylidene fluoride (PVDF)‐based graphite electrodes are introduced as model systems to quantify the electrolyte decomposition, solid electrolyte interphase (SEI) formation, and the corresponding kinetic evolution transition. A noncatalytic electrolyte reduction path on the CMC‐based electrode and a catalytic reduction path on the PVDF‐based electrode are identified, in terms of the reduction overpotential and product selectivity. The electrolyte reduction and/or SEI formation are found to occur in a successive, two‐step manner, starting with the electrochemical reduction at a potential above 0.35 V where no potassiation has happened (step I), and followed by the thermodynamically accelerated electrolyte reduction at a potential below 0.35 V (step II). Kinetics analysis reveals the former is charge transfer‐controlled for both CMC and PVDF‐based electrodes, and the latter involves a kinetic transition to SEI resistance controlled for the PVDF system, while it is charge transfer‐controlled for the CMC system. All these examples, highlight that binder chemistry plays a dominant role in the electrolyte decomposition and electrode/electrolyte interfacial properties, and promote a better fundamental understanding of electrolyte reduction. [ABSTRACT FROM AUTHOR]

High‐energy lithium‐ion batteries (LIBs) can be realized with the use of nickel‐rich materials, however, their reversible operation requires long‐term cathode‐electrolyte interfacial (CEI) stability, especially for high‐temperature applications, but how the CEIs evolves during operation is still a mystery. The unstable CEIs have been recently ascribed to them generating/disappearing/regenerating during Li+ extraction/insertion by in situ Fourier Transform Infrared Spectroscopy spectrum. Herein, a strategy of insoluble CEI is proposed toward addressing the interfacially induced deterioration of cathodes with a focus on Ni‐rich layered oxides. Incorporating unsaturated units (CC/CC) to siloxane as electrolyte additives advances the commercial LiNi0.8Co0.1Mn0.1O2/graphite cells up to around 300 cycles at 60 °C with more than 85% capacity retention, along with the LiCoO2 cells reaching ≈90% capacity retention over 350 cycles under 80 °C. The experimentally and theoretically detailed investigation shows that the higher unsaturation bond with high reactive sites show more polymerization via a 3D topological pathway to form insoluble CEI species, leading to suppression of parasitic reactions, corrosive acid, transition‐metal dissolution, stress corrosive cracking, and impedance growth. The scientific discoveries of this study highlight the pivotal role of electrode–electrolyte interactions and recapitulates the tried‐and‐true "electrolyte" approach for the future development of high‐energy batteries under extreme temperature conditions. [ABSTRACT FROM AUTHOR]

Nickel hydroxide (Ni(OH)2) is a promising electrocatalyst for the 5‐hydroxymethylfurfural oxidation reaction (HMFOR) and the dehydronated intermediates Ni(OH)O species are proved to be active sites for HMFOR. In this study, Ni(OH)2 is modified by platinum to adjust the electronic structure and the current density of HMFOR improves 8.2 times at the Pt/Ni(OH)2 electrode compared with that on Ni(OH)2 electrode. Operando methods reveal that the introduction of Pt optimized the redox property of Ni(OH)2 and accelerate the formation of Ni(OH)O during the catalytic process. Theoretical studies demonstrate that the enhanced Ni(OH)O formation kinetics originates from the reduced dehydrogenation energy of Ni(OH)2. The product analysis and transition state simulation prove that the Pt also reduces adsorption energy of HMF with optimized adsorption behavior as Pt can act as the adsorption site of HMF. Overall, this work here provides a strategy to design an efficient and universal nickel‐based catalyst for HMF electro‐oxidation, which can also be extended to other Ni‐based catalysts such as Ni(HCO3)2 and NiO. [ABSTRACT FROM AUTHOR]

While the intima‐media thickness (IMT) of the cavernous artery was used for diagnosis for vascular erectile dysfunction (ED) with more accuracy than the peak systolic velocity, the role of the IMT in predicting treatment responses remained unexamined. A total of 136 patients with ED were enrolled. The baseline clinical and laboratory characteristics were collected. Penile Doppler ultrasonography (PDU) was performed on all patients by a blinded sonographer. Sildenafil was administrated to all patients with an adjusted dose of 50 or 100 mg on demand over a period of 3 months. A follow‐up was conducted on all patients using the Erectile Hardness Score (EHS) questionnaire along with the visual and tactile version of the standardised EHS tool. The peak systolic velocity (PSV) and IMT were compared between sildenafil responders and sildenafil nonresponders, while receiver operator characteristic (ROC) curves were used to calculate the cut‐off values and compare the test power respectively. There was no statistical difference from the baseline characteristics. The IMT of cavernous artery was more accurate than PSV to predict the sildenafil response (AUC = 0.809, 0.626 respectively). IMT could predict sildenafil responders more accurately than PSV, and the cut‐off value of the IMT of the cavernous artery was less than 0.22 mm. [ABSTRACT FROM AUTHOR]

Understanding plant water stress (PWS) in the soil‐plant‐atmosphere‐continuum (SPAC) that connects water supply from soil, water demand from atmosphere, and plant self‐regulation is a prerequisite for efficient irrigation in response to water scarcity. Currently, PWS can be defined in various ways, for example, based on environmental factors and/or plant‐centric metrics. The environment‐based metrics usually do not take plants into consideration. Regarding the existing plant‐centric metrics, their interconnections and abilities to capture the physical water constraints from both soil water supply and atmospheric water demand are still unclear. This research investigates the theoretical foundations behind different PWS metrics, and assesses their efficacy and potentials for irrigation scheduling. This study first investigated the interconnections among different PWS metrics and the co‐regulation of soil moisture and vapor pressure deficit (VPD) on the plant‐centric metrics through an advanced process‐based model, ecosys. We then use ecosys to test different PWS metrics' performance in guiding irrigation in terms of water use, maize yield, and economic profits. The case study was conducted at sites across a dramatic rainfall gradient in Nebraska, the largest irrigation state in the United States Corn Belt. The ecosys simulation indicates that canopy water potential and stomatal conductance (gs) are the most effective plant‐centric metrics in the SPAC system in indicating PWS. In addition, our findings show that using the plant‐centric metrics‐based irrigation schemes, which capture the co‐regulation of soil moisture and VPD, can improve producers' economic profits through water savings. Key Points: We conducted a systematic study to interpret six plant water stress (PWS) metrics and to assess their efficacy for guiding irrigationCanopy water potential and stomatal conductance are the most effective PWS metrics to characterize co‐regulation of soil moisture and vapor pressure deficitThe plant‐centric irrigation schemes could save irrigation water use compared with soil‐moisture‐only metrics [ABSTRACT FROM AUTHOR]

Microbial communities analysis is drawing growing attention due to the rapid development fire of high-throughput sequencing techniques nowadays. The observed data has the following typical characteristics: it is high-dimensional, compositional (lying in a simplex) and even would be leptokurtic and highly skewed due to the existence of overly abundant taxa, which makes the conventional correlation analysis infeasible to study the co-occurrence and co-exclusion relationship between microbial taxa. In this article, we address the challenges of covariance estimation for this kind of data. Assuming the basis covariance matrix lying in a well-recognized class of sparse covariance matrices, we adopt a proxy matrix known as centered log-ratio covariance matrix in the literature. We construct a Median-of-Means estimator for the centered log-ratio covariance matrix and propose a thresholding procedure that is adaptive to the variability of individual entries. By imposing a much weaker finite fourth moment condition compared with the sub-Gaussianity condition in the literature, we derive the optimal rate of convergence under the spectral norm. In addition, we also provide theoretical guarantee on support recovery. The adaptive thresholding procedure of the MOM estimator is easy to implement and gains robustness when outliers or heavy-tailedness exist. Thorough simulation studies are conducted to show the advantages of the proposed procedure over some state-of-the-arts methods. At last, we apply the proposed method to analyze a microbiome dataset in human gut. [ABSTRACT FROM AUTHOR]

Summary: Currently, Recommender Systems (RS) have been ubiquitously applied to various online applications and obtained tremendous success due to their capability to overcome information overload; however, the available Side Information (SI), such as demographics and attributions of items, is always neglected. Actually, SI could reflect user's interests and preference, and even influence user's decision over items; therefore, it would be greatly helpful to leverage side information to improve the performance of RS, which is already partly certificated in previous research studies. Motivated by this, in this article, a novel multi‐task learning‐based recommendation system referred to as LGP‐RS is proposed, which takes utility functions mapping from the non‐linear side information to low‐rank feature space with Gaussian process (GP) priors, for users and items, respectively. In addition, Laplace approximation method is employed to approximate the posterior distribution for the utility functions, and gradient‐based method is employed to learn the hyperparameters for GP. This flexible approach is able to capture the non‐linear high‐order interactions within side information, reduce the prediction uncertainty, and provide personalized top‐N recommendation. Experimental analysis over three real‐world datasets demonstrates that LGP‐RS could deal with both explicit and implicit side information simultaneously, and significantly outperforms state‐of‐the‐art approaches. [ABSTRACT FROM AUTHOR]

Objectives: To explore the feasibility of shear wave elastography (SWE) in the evaluation of arterial erectile dysfunction (ED). Methods: From November 2018 to November 2019, 26 patients with arterial ED and 30 patients with non‐vascular ED were prospectively included. SWE values of corpus cavernosum penis (CCP) and the flow velocity of cavernous artery for all patients in both before intracavernous injection (ICI) (flaccid state) and after ICI (erectile state) were measured. Performance of SWE value in assessing arterial ED was studied. Correlation between SWE value of CCP and the age of patients was also investigated. Results: ICI significantly reduced SWE values in both arterial and non‐vascular group (from 19.57 ± 6.33 KPa to 12.17 ± 3.64 KPa in the first, and from 19.91 ± 6.69 KPa to 8.04 ± 3.13 KPa in the former, both P <.001). SWE values of CCP after ICI in arterial ED were significantly larger than that in non‐vascular ED (P <.001). SWE values of CCP before ICI negatively correlated with age of patients in arterial ED (r = − 0.601, P <.001). With a cutoff value of 7.75 KPa, the area under curve, specificity, sensitivity, PPV, and NPV of SWE values of CCP after ICI in distinguishing arterial ED from non‐vascular ED were 0.810, 63.3%, 96.2%, 96.2%, and 70%, respectively. Conclusions: SWE was expected to be a potential technique for the noninvasive, simply operated, repeatable and quantitative evaluation of arterial ED. Access the CME test here and search by article title. [ABSTRACT FROM AUTHOR]

Objective: After bone prosthesis replacement, M1‐type macrophage polarization can be induced by titanium (Ti) particles and produce inflammatory, leading to osteolysis. Adipocyte‐derived exosomes (ADEs) exert immune‐modulatory impact on the macrophage, while whether it can inhibit the macrophage polarization induced by Ti is unclear. This study focuses on the M1‐type macrophage and aims to determine the effect of ADEs on Ti‐induced M1‐type macrophage polarization in osteolytic mice and the involved mechanism. Methods: Ti particle‐induced osteolysis mouse model was established and macrophages were isolated from the osteolysis site. The levels of NLRP3 and specific markers for M1‐type macrophage were determined. ADEs isolated from adipocyte cell line 3T3‐L1, or conditioned ADEs with low‐expressed miR‐34a isolated from 3T3‐L1 transfected with miR‐34a inhibitor were co‐cultured with RAW 264.7 to determine their impact on the polarization of macrophage. Results: ADEs reduced the M1‐type macrophage polarization and caused the upregulation of miR‐34a in macrophage of the osteolysis site of the osteolysis mouse model. Also, the level of miR‐34a in ADEs was higher than that in the adipocyte. The conditioned ADEs expressed a low level of miR‐34a and boosted the Ti‐induced M1‐type polarization. MiR‐34a could target NLRP3 and negatively regulated its expression. Moreover, NLRP3 knockdown in macrophage restricted the conditioned ADEs to promote macrophage towards to Ti‐induced M1‐type polarization. The inhibitory function of ADEs on M1‐type macrophage polarization was abolished by miR‐34a silencing in the mouse osteolysis model. Conclusion: The miR‐34a carried by ADEs reduced the polarization of M1‐type macrophages by targeting macrophage NLRP3 during Ti particle‐induced osteolysis. [ABSTRACT FROM AUTHOR]

The gold‐standard method for diagnosing arteriogenic erectile dysfunction (AED) is the penile Doppler ultrasonography. We proposed a novel method for predicting AED using ultrasonic shear wave elastography (SWE) considering that the former was invasive and variable. A total of 98 male patients were enrolled in our study, referred for ED between December 2018 and October 2020. For comparison, we also included 42 volunteers from the Healthy Physical Examination Center of our hospital. The Penile Doppler Ultrasonography (PDU) and SWE were performed for all patients with the intracavernosal injection (ICI). We named three groups as AED group, nonvascular ED group and healthy controls group. No statistically significant differences were found among the three groups in terms of demographic and clinical characteristics. There were no significant differences in IIEF‐5 between AED and nonvascular ED. A significant (r = 0.642, p < 0.0001) positive correlation between flaccid and erectile SWE was observed. With a cut‐off value of 13.45 KPa, the area under curve, specificity, and sensitivity of the SWE values under the flaccid state in distinguishing AED from healthy subjects were 0.867, 0.786 and 0.896 respectively. The SWE value in the flaccid state can distinguish the AED from healthy subjects. [ABSTRACT FROM AUTHOR]

The nitrogenous nucleophile electrooxidation reaction (NOR) plays a vital role in the degradation and transformation of available nitrogen. Focusing on the NOR mediated by the β‐Ni(OH)2 electrode, we decipher the transformation mechanism of the nitrogenous nucleophile. For the two‐step NOR, proton‐coupled electron transfer (PCET) is the bridge between electrocatalytic dehydrogenation from β‐Ni(OH)2 to β‐Ni(OH)O, and the spontaneous nucleophile dehydrogenative oxidation reaction. This theory can give a good explanation for hydrazine and primary amine oxidation reactions, but is insufficient for the urea oxidation reaction (UOR). Through operando tracing of bond rupture and formation processes during the UOR, as well as theoretical calculations, we propose a possible UOR mechanism whereby intramolecular coupling of the N−N bond, accompanied by PCET, hydration and rearrangement processes, results in high performance and ca. 100 % N2 selectivity. These discoveries clarify the evolution of nitrogenous molecules during the NOR, and they elucidate fundamental aspects of electrocatalysis involving nitrogen‐containing species. [ABSTRACT FROM AUTHOR]

The increased integration interaction of bis 9,10‐dihydro‐9‐oxa‐ 10‐phospaphenanthrene‐10‐oxide (DOPO) phosphonate (abbreviated as FR) including ethyl‐(FR1), phenethyl‐(FR2), naphthalene‐(FR3) with the aryl group and hexa‐phenoxy‐cyclotriphosphazene (HPCP) on flame‐retardant polyamide 6 (PA6) were investigated. The role of the aryl group in FR on flame‐retarding PA6 was analyzed. Results showed that PA6 composites with greatly reduced fire hazards possessed a high‐limiting oxygen index value of 34% and achieved a UL‐94 V‐0 rating and sharply decreased peak heat release rate by simultaneously adding FR and HPCP. Flame inhibition effect acted as the main mechanism for FR and HPCP in flame‐retarding PA6. Gas phase action increased with the number of aryl groups. HPCP played a catalytic effect in the condensed phase. Particularly, the result of residue analysis after cone test implied that char surface with network structure was formed, and the structure became compact and continuous with the increase in the number of aryl groups. Furthermore, the aryl group played an important role in aiding the PA6 composites in the construction of a network protective char layer on the surface during combustion. [ABSTRACT FROM AUTHOR]

Carbon material has emerged as a highly promising anode for sodium‐ion batteries (SIBs) due to its abundance of resources, cost‐effectiveness, and high carbon yield. This work elaborately designs the precursor structure for the self‐assembly of melamine‐cyanuric acid on the anthracite surface through hydrogen bonding, and successfully constructs N‐doped carbon with tailored microstructure and expanded interlayer spacing. Serving as anode for SIBs, the optimized sample delivers high specific capacity (371.3 mAh g−1 at 0.05 A g−1), superior rate capability (295.8 mAh g−1 at 10.0 A g−1), and excellent ultra‐long cycling performance (the retention of 91.5% after 3000 cycles at 0.5 A g−1). The systematic investigations reveal the enhancement of sodium‐ion storage in the low‐voltage plateau region involving the interlayer intercalation coupled with nanopores filling. It is discovered that the microporous structure formed by the appropriate graphite sheet angle influences the migration and storage of sodium ions. Density functional theory calculations indicate that the adsorption capacity for sodium ion is enhanced and the migration energy barrier perpendicular to the graphite layer is reduced at the appropriate angle of 8°. This study provides novel insights into the sodium‐ion storage mechanism, offering guidance for the better design of anthracite‐based carbon anode with superior performance. [ABSTRACT FROM AUTHOR]

Pre‐diabetes is characterized by impaired glucose tolerance (IGT) and/or impaired fasting glucose. Impairment of skeletal muscle function is closely associated with the progression of diabetes. However, the entire pathological characteristics and mechanisms of pre‐diabetes in skeletal muscle remain fully unknown. Here, we established a mouse model of pre‐diabetes, in which 6‐week‐old male C57BL6/J mice were fed either normal diet or high‐fat diet (HFD) for 8 or 16 weeks. Both non‐fasting and fasting glucose levels and the results of glucose and insulin tolerance tests showed that mice fed an 8‐week HFD developed pre‐diabetes with IGT; whereas mice fed a 16‐week HFD presented with impaired fasting glucose and impaired glucose tolerance (IFG‐IGT). Mice at both stages of pre‐diabetes displayed decreased numbers of mitochondria in skeletal muscle. Moreover, IFG‐IGT mice exhibited decreased mitochondrial membrane potential and ATP production in skeletal muscle and muscle degeneration characterized by a shift in muscle fibers from predominantly oxidative type I to glycolytic type II. Western blotting and histological analysis confirmed that myoblast differentiation was only inhibited in IFG‐IGT mice. For primary skeletal muscle satellite cells, inhibition of differentiation was observed in palmitic acid‐induced insulin resistance model. Moreover, enhanced myoblast differentiation increased glucose uptake and insulin sensitivity. These findings indicate that pre‐diabetes result in mitochondrial dysfunction and inhibition of myoblast differentiation in skeletal muscle. Therefore, interventions that enhance myoblast differentiation may improve insulin resistance of diabetes at the earlier stage. Mitochondrial dysfunction may occur earlier than and result in inhibition of myoblast differentiation in a mouse model of pre‐diabetes. Mitochondrial dysfunction in skeletal muscle may contribute to the progression of pre‐diabetes. [ABSTRACT FROM AUTHOR]

A variety of benzofuranone‐based spiroisochromenes were originally designed and synthesized to gain insight into the oxa‐6π electrocyclic reaction of cis,cis‐1,8‐dioxatetraene for the first time. The stability of the 1,8‐dioxatetraene intermediate is governed by its steric congestion and can be fine‐tuned through modification of the backbone structure, leading to the reactivity differences in the 6π electrocyclic reaction and the emergence of photochromic properties. Upon exposure to light, benzofuranone‐based spiroisochromenes undergo isomerization to give 1,8‐dioxatetraene intermediates. The stability of the intermediate is governed by its steric congestion and can be fine‐tuned through modification of the backbone structure, leading to the emergence of photochromic properties. [ABSTRACT FROM AUTHOR]

Nanocomposite fibers of carboxylated multiwalled carbon nanotubes (MWNTs‐COOH)‐reinforced polyamide 6 (PA6), which have good mechanical properties, were fabricated by a ball‐milling and melt spinning process. The ball‐milling method was used to prepare PA6/MWNTs‐COOH nanocomposite powders to address the key issue of dispersing MWNTs‐COOH into the PA6 matrix uniformly. The effects of both the milling time and MWNTs‐COOH loading on the mechanical properties of PA6/MWNTs‐COOH nanocomposite fibers were investigated. Transmission electron microscopy, Raman spectroscopy, and X‐ray diffraction were used to study the morphology and microstructure of MWNTs‐COOH in compound powders after ball‐milling. Scanning electron microscopy micrographs indicated that secondary agglomeration of MWNTs‐COOH occurred after ball‐milling for 5 h, and the best dispersing time was 3 h. The mechanical properties of the nanocomposite fibers fabricated by ball‐milling were much higher than those of the control and composites fabricated by conventional melt mixing. The results of the differential scanning calorimetry revealed the close relationship between the dispersibility and crystallinity. This method, which does not require the use of solvent, has great potential for industrial application. POLYM. COMPOS., 39:4298–4309, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Lignin model compounds undergo aerobic oxidation upon relay action of light and copper to afford isolable fragments. Considerably better efficiency and different product distribution are achieved in comparison to thermal copper‐catalyzed aerobic fragmentation. Lignin model compounds efficiently broke down through light/copper relayed aerobic oxidation with different product distribution in comparison to thermal copper‐catalyzed aerobic fragmentation. [ABSTRACT FROM AUTHOR]

Abstract: A photocatalyzed reaction of pyridine N‐oxides with alkenes gives ortho‐alkylated pyridines with cleavage of the carbon–carbon double bond. Benzyl and secondary alkyl groups are incorporated at the ortho position of pyridines in one pot. [ABSTRACT FROM AUTHOR]

Aphotocatalyzed reaction of pyridine N-oxides with alkenes gives ortho-alkylated pyridines with cleavage of the carbon–carbon double bond. Benzyl and secondary alkyl groups are incorporated at the ortho position of pyridines in one pot. [ABSTRACT FROM AUTHOR]

Abstract: In order to explore the isothermal growth crystallization mechanism of vanadium‐chromium slag, the growth behavior of spinel crystals in vanadium‐chromium slag is investigated in this paper by using SEM/EDS and crystal size distribution (CSD) theory. It is found that with the prolongation of holding time at 1523 K, the mean diameter of spinel crystals decrease in the initial 30 min and then increased to 60.34 µm. The area fraction of spinel crystals increases from 35.56 to 54.28%. While at 1623 K, expect for the transient decrease at 30 min, the mean diameter of spinel crystals also increases obviously with the prolongation of time. The area fraction of spinel crystals increase from 31.28 to 50%. The results reveal that low temperature befits the growth of spinel crystals. All CSD shapes of vanadium‐chromium slag are lognormal distribution, which implies that the growth of the spinel crystals is controlled by surface and supply, and more inclined to supply control. [ABSTRACT FROM AUTHOR]

Abstract: A practical zinc acetate dihydrate‐catalyzed reductive amination of various carbonyl compounds with N,N‐dimethylformamide (DMF) as dimethylamino (Me2N) source, reductant and solvent has been developed. This reaction shows broad substrate scope, good functional group tolerance, avoids the need for a pressure‐proof reactor and column chromatographic isolation operations and gives up to 98% yield, to make it an attractive method for the preparation of tertiary N,N‐dimethylamines. [ABSTRACT FROM AUTHOR]

Although protease activated receptor-1 (PAR-1) has been confirmed as an oncogene in many cancers, the role of PAR-1 in giant cell tumor (GCT) of bone has been rarely reported. The mechanism of PAR-1 in tumor-induced osteoclastogenesis still remains unclear. In the present study, we detected that PAR-1 was significantly upregulated in GCT of bone compared to normal tissues, while TGF-β was also overexpressed in GCT tissues and could promote the expression of PAR-1 in a dose and time dependent manner. Using the luciferase reporter assay, we found that two downstreams of TGF-β, Smad3 and Smad4, could activate the promoter of PAR-1, which might explain the mechanism of TGF-β induced PAR-1 expression. Meanwhile, PAR-1 was also overexpressed in microvesicles from stromal cells of GCT (GCTSCs), and might be transported from GCTSCs to monocytes through microvesicles. In addition, knockout of PAR-1 by TALENs in GCTSCs inhibited tumor growth, angiogenesis and osteoclastogenesis in GCT in vitro. Using the chick CAM models, we further showed that inhibition of PAR-1 suppressed tumor growth and giant cell formation in vivo. Using microarray assay, we detected a number of genes involved in osteoclastogenesis as the possible downstreams of PAR-1, which may partly explain the mechanism of PAR-1 in GCT. In brief, for the first time, these results reveal an upstream regulatory role of TGF-β in PAR-1 expression, and PAR-1 expression promotes tumor growth, angiogenesis and osteoclast differentiation in GCT of bone. Hence, PAR-1 represents a novel potential therapeutic target for GCT of bone. [ABSTRACT FROM AUTHOR]

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As the most predominant type of failure for steel-concrete composite beams (SCCBs) in negative moment area, distortional buckling is significantly impacted by the interaction effect between the applied loading and the torsional-lateral restraint stiffness of the bottom flange, which is termed as loading-restraint interaction here for short. Recently, a modified elastic foundation beam method capable of considering the interaction effect properly was proposed to calculate critical buckling moment for SCCBs under negative uniform moment. As a sequel to such development, a functional relationship between two dimensionless auxiliary parameters (i.e. equivalent slenderness ratio and equivalent moment coefficient) is discovered in this study. On the basis of the close association between the pair of dimensionless parameters, empirical formulas are derived in a remarkably simply explicit form to evaluate the critical buckling moment for SCCBs under negative uniform moment or moment gradient. These formulas are simple, user-friendly and of practical use. Compared with conventional approaches without considering the loading-restraint interaction effect, the practical approach developed in this paper can achieve higher accuracy and is more easy-implemented. The study lays a foundation for determining the ultimate bearing capacity of SCCBs considering moment gradient effect rapidly. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Bone metastasis from cancer of unknown primary (BMCUP) brings poor survival prognosis and its management remains controversial. Sunitinib (SUTENT) proved effective in many sorts of solid tumors but has never been applied for patients with occult primary cancers, and there is no study to identify sensitive or resistant biomarkers for sunitinib therapy in CUP patients. An analysis was carried out to investigate the efficacy of sunitinib by multivariate survival analysis of 286 patients with BMCUP. We further carried out multivariate analysis to identify histological and clinical biomarkers that could predict sensitivity or resistance for sunitinib therapy. Of the 286 patients included from January 2011 to March 2016, sunitinib therapy proved effective to prolong survival in patients with BMCUP. Sensitive and resistant biomarkers were identified in histological specimen of patients receiving sunitinib therapy. Clinical factors were also identified that predict poor survival prognosis for sunitinib therapy. Sunitinib therapy proved effective to prolong survival in patients with BMCUP. Sensitive markers for sunitinib therapy include KDR positivity and early-developed treatment-induced hypertension. Resistance factors for sunitinib include VEGF positivity, CAIX positivity and squamous cell carcinoma pathology type. Prolonged symptom time and severe weight loss before therapy seemed to be associated with poor survival prognosis for sunitinib therapy. [ABSTRACT FROM AUTHOR]

It remains unclear if China's current HIV antibody testing algorithm misses a substantial number of HIV infected individuals. Of 196 specimens with indeterminate or negative results on HIV western blot (WB) retrospectively examined by HIV-1 nucleic acid test (NAT), 67.57% (75/111) of indeterminate WB samples, and 16.47% (14/85) of negative WB samples were identified as NAT positive. HIV-1 loads in negative WB samples were significantly higher than those in indeterminate WB samples. Notably, 86.67% (13/15) of samples with negative WB and double positive immunoassay results were NAT positive. The rate of HIV-1 infections missed by China's current HIV testing algorithm is unacceptably high. Thus, China should consider using NAT or integrating fourth generation ELISA into current only antibodies-based HIV confirmation. J. Med. Virol. 88:1462-1466, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In many applications, the parameters of interest are estimated by solving non-smooth estimating functions with U-statistic structure. Because the asymptotic covariances matrix of the estimator generally involves the underlying density function, resampling methods are often used to bypass the difficulty of non-parametric density estimation. Despite its simplicity, the resultant-covariance matrix estimator depends on the nature of resampling, and the method can be time-consuming when the number of replications is large. Furthermore, the inferences are based on the normal approximation that may not be accurate for practical sample sizes. In this paper, we propose a jackknife empirical likelihood-based inferential procedure for non-smooth estimating functions. Standard chi-square distributions are used to calculate the p-value and to construct confidence intervals. Extensive simulation studies and two real examples are provided to illustrate its practical utilities. [ABSTRACT FROM AUTHOR]

Background and aims To decrease infectious disease transmission, China is expanding methadone maintenance treatment (MMT). This study evaluated the prevalence of hepatitis C virus (HCV) infection at MMT entry, seroconversion rates after admission and potential risk factors for HCV seroconversion during MMT in Wuhan, China. Design Cross-sectional survey of all patients entering MMT and prospective follow-up of patients HCV seronegative at admission. Setting All MMT clinics in Wuhan, China. Participants A total of 12 755 opiate-dependent individuals entering MMT between May 2006 and June 2011; 1200 participants HCV seronegative at admission were followed. Measurements Serological tests for HCV and self-report data on risk behaviors at MMT admission; urine toxicology results and repeated assessments of serological status and risk behaviors during treatment on patients HCV seronegative at admission. Findings HCV seroprevalence at admission was 72.1% [95% confidence interval (CI) = 71.3-72.9%] and 555/1200 (46.3%, 95% CI = 43.5-49.1%) patients seroconverted to HCV during MMT. The mean time to HCV seroconversion was 3 (95% CI = 2.84-3.07) years with a cumulative seroconversion rate of 34.5 (95% CI = 31.5-36.9) per 100 person-years. Significant predictors of HCV conversion included injection drug use in the past 30 days [relative hazard (RH) 2.0, 95% CI: 1.6 - 2.4, P=0.002] and the rate of opiate-positive urine tests during MMT (RH 2.0, 95% CI = 1.3-3.1, P<0.001). Conclusions Methadone maintenance treatment patients in Wuhan, China show a high prevalence of hepatitis C virus at admission (72.1%) and a high rate of seroconversion during treatment (46.3%). Seroconversion is associated with continuing injection drug use. [ABSTRACT FROM AUTHOR]

Homologous recombination (HR) is a key process during meiosis in reproductive cells and the DNA damage repair process in somatic cells. Although chromatin structure is thought to be crucial for HR, only a small number of chromatin modifiers have been studied in HR regulation so far. Here, we investigated the function of CURLY LEAF ( CLF), a Polycomb-group (PcG) gene responsible for histone3 lysine 27 trimethylation (H3K27me3), in somatic and meiotic HR in Arabidopsis thaliana. Although fluorescent protein reporter assays in pollen and seeds showed that the frequency of meiotic cross-over in the loss-of-function mutant clf-29 was not significantly different from that in wild type, there was a lower frequency of HR in clf-29 than in wild type under normal conditions and under bleomycin treatment. The DNA damage levels were comparable between clf-29 and wild type, even though several DNA damage repair genes (e.g. ATM, BRCA2a, RAD50, RAD51, RAD54, and PARP2) were expressed at lower levels in clf-29. Under bleomycin treatment, the expression levels of DNA repair genes were similar in clf-29 and wild type, thus CLF may also regulate HR via other mechanisms. These findings expand the current knowledge of PcG function and contribute to general interests of epigenetic regulation in genome stability regulation. [ABSTRACT FROM AUTHOR]

Vulcanization kinetics of constant viscosity natural rubber (CVNR) prepared with hydroxylamine hydrochloride was studied by using a Rheometer MDR2000. The results show that the first stage of curing period follows first-order reaction, but the induction period and the end stage of curing period does not. The calculated reaction order n of the end stage of curing period of CVNR is in the range of 0.01-0.52, and that of natural rubber (NR) is in the range of 0.38-0.66. The reaction orders of the end stages of curing periods of CVNR and NR increase with increasing curing temperature, and the reaction order of the end stage of curing period of CVNR is smaller than that of NR at the same temperature. The rate constants of the induction period, the first stage of curing period and the end stage of curing period of CVNR are smaller than that of NR at the same temperature. The activation energies of the induction period, the first stage of curing period and the end stage of curing period of CVNR are greater than that of NR. The activation energy of the induction period of CVNR is increased by13.52%, the activation energy of the first stage curing period of CVNR is increased by 3.95%, and the activation energy of the end stage of curing period of CVNR is increased by 1.60% compared with the activation energies of NR. The time tdis of CVNR is longer than that of NR at the same temperature. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

In China, the rate of human immunodeficiency virus (HIV) testing is increasing among men who have sex with men. The purpose of the present study was to describe HIV-related biomarkers and selected demographic variables of persons with newly diagnosed HIV/AIDS, among men who have sex with men in particular, in Wuhan China. Demographic indicators, and CD4+ T cell counts and HIV-1 viral load were collected from individuals newly identified as HIV-1 antibody positive during 2011. Of 176 enrolled patients, 132 (75.0%) were men who have sex with men. This group was significantly younger and had higher CD4+ T cell counts than patients who were likely infected through heterosexual contact. Most men who have sex with men (56.6%) were discovered by initiative investigation. Among heterosexual patients CD4+ T cell counts and HIV-1 viral load were significantly correlated; among the group of men who have sex with men, no such association was found. J Med. Virol. 85:1687-1691, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A convenient method for the synthesis of N-arylisatins from 2-(arylamino)acetophenones by using SeO2 as an oxidant is described. Various substituted N-arylisatins were selectively obtained in good to excellent yields. The reaction tolerates a wide range of functionalities. [ABSTRACT FROM AUTHOR]

In this work, the wet natural rubber granules were dried by hot air and by microwave at 115°C, respectively; the morphological structures of dried natural rubber granules were studied by using a scanning electronic microscope, whereas the thermal oxidative properties of dried natural rubber granules were investigated by comparison of variation in properties before and after aging, and the changes in the thermal oxidative decompose temperatures. The results showed that it needed 13.47 min for microwave drying and 210.00 min for hot air drying to reduce the moisture content of wet natural rubber to the required value. The granules of natural rubber dried by microwave were of rough surfaces and the cutting traces produced during the processing of wet natural rubber remained on the natural rubber surface; whereas, the natural rubber granules dried by hot air were of smooth surfaces, and the cutting traces produced during the processing of wet granules disappeared. The thermal oxidative resistance of vulcanized natural rubber dried by microwave improved significantly. The initial plasticity ( P0), plasticity retention index, and thermo-oxidative decomposition temperature of natural rubber dried by microwave were higher than those of natural rubber dried by hot air. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Let { N( t), t > 0} be a Poisson process with rate λ > 0, independent of the independent and identically distributed random variables [ABSTRACT FROM AUTHOR]

Effect of non-rubber components on vulcanization kinetics of natural rubber was studied with the use of a Rheometer MDR-2000. The results show that the rate constants of induction period and curing period of natural rubber (NR) are greater than that of natural rubber extracted with acetone (NRE), and the activation energies of induction period and curing period of NR are lower than that of NRE. The activation energy of induction period of NR is reduced by16.9% and the activation energy of curing period of NR is reduced by 3.2% compared to the activation energies of NRE. The time tdis of NR is shorter than that of NRE at the same temperature. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]