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The speciation of heavy metals in soil is a better indicator for assessing the bioavailability than the total concentration. Soil pH is a vital factor influencing the particulate-bound metal speciation and the metal dynamics at rhizosphere soil-root interface. In this study, greenhouse pot experiment was conducted to reveal the influence of pH on the speciation of cadmium (Cd) in solid phase of soil and the amount of Cd uptake by different ecotype plants. The results illustrated that the exchangeable Cd decreased obviously with the increase of soil pH, while the residual Cd displayed the reverse. The amount of Cd uptake by plants increased with pH decreased, and pH 5.5 exhibited the optimum for plants growth and metal uptake. Furthermore, the biomass and uptake capability of the hyperaccumulator plants (Sedum alfredii and Beta vulgaris var. cicla L with red leaves) were higher than the corresponding non-hyperaccumulator plants. Results indicated that the pH decrease and rhizosphere effects of hyperaccumulator could facilitate the activation of Cd and enhance the phytoremediation efficiency significantly. [ABSTRACT FROM AUTHOR]

When launch vehicles encounter thrust drop f4aults during endoatmospheric flight, conventional nominal trajectory-based guidance methods may fail to compensate adequately; and the launch mission may culminate in failure. In this paper, we present an improved parallel-structured Newton-type guidance (PSNG) algorithm to address the aforementioned challenge. Compared to the basic PSNG algorithm, the proposed algorithm entails two major improvements: determination of the free final time and handling of the path constraint using the projected Newton-type method. Except for inheriting the benefits of the original PSNG algorithm, the improved algorithm can solve the free-final-time and path-constrained ascent guidance problems directly. Numerical simulations with various ascent scenarios of thrust drop faults are conducted, and the results show that the improved algorithm has high computational efficiency, accuracy, and robustness against disturbances and uncertainties. [ABSTRACT FROM AUTHOR]

This paper presents a parallel-structured Newton-type guidance law for the missile guidance problems. In the proposed approach, the modified Chebyshev-Picard iteration is used to approximate the dynamic equations, by which the continuous-time guidance problem is transcribed into a sequence of discrete-time subproblems, and both serial and parallel computing can be supported. The subproblems can then be iteratively solved by the Newton-type methods. Numerical demonstrations in a 3-D air-to-surface missile guidance problem with both impact-time and impact-angle constraints are provided to illustrate the effectiveness of the proposed guidance law. The simulation results show that the proposed guidance is superior to the state-of-the-art adaptive damped Newton-type guidance and quasi-spectral model predictive static programming in both computational efficiency and accuracy, even before parallel implementation. [ABSTRACT FROM AUTHOR]

Background: Phototherapy is one of the treatments for vitiligo. To be specific, the combination of narrowband ultraviolet B (NB-UVB) with topical preparations has currently become the most common therapeutic modality. Moreover, the research on new topical drug has been a hot issue in the field of vitiligo. Objective: At present, simvastatin has been considered as a potential therapeutic agent for the treatment of vitiligo. To the best of our knowledge, this is the first case report concerning the successful application of NBUVB combined with topical simvastatin in the treatment of vitiligo. Methods: In this article, a clinical case report was presented, where the patient was not responsive to NB-UVB but was markedly responsive to the treatment of UVB combined with topical simvastatin. Results: A 34-year-old Chinese female patient with vitiligo was cured by NB-UVB combined with topical simvastatin solution. Conclusions: NB-UVB combined with topical simvastatin may be a potential treatment against vitiligo. This research was approved by the Medical Ethics Committee of Third People’s Hospital of Hangzhou. [ABSTRACT FROM AUTHOR]

Introduction: Unresectable hilar cholangiocarcinoma (UHC) is a malignant tumor and has a poor prognosis. IRE is a novel non-thermal ablative therapy that causes cellular apoptosis via electrical impulses. To compare the curative effect for UHC, chemotherapy plus concurrent IRE and chemotherapy alone were set up. Materials and methods: From July 2015 to May 2019, 47 patients with UHC were analyzed to chemotherapy + IRE group (n = 23) or chemotherapy alone group (n = 24) in this study. Treatment response was assessed with computed tomography (CT) or magnetic resonance imaging (MRI) 1 month after treatment and every 3 months thereafter. Local tumor progression (LTP), time to LTP, overall survival (OS) and procedure-related complications were compared between the two groups. Results: Chemotherapy plus concurrent IRE group showed a tendency toward a decreased rate of LTP (16.7% vs. 39.5%; p = 0.039) and an increased complete response rate (52.2% vs. 12.5%; p = 0.011) compared with chemotherapy alone group. Time to LTP was significantly longer in the chemotherapy plus concurrent IRE group compared to chemotherapy alone group (11.2 months vs. 4.2 months; p = 0.001). Median OS was significantly longer in the chemotherapy plus concurrent IRE group compared to chemotherapy alone group (19.6 months vs. 10.2 months; p = 0.001). Conclusions: Chemotherapy plus concurrent IRE improved local control and prolonged time to LTP and OS in patients with UHC. [ABSTRACT FROM AUTHOR]

Kuding tea, the leaves of Ilex Kudingcha C.J. Tseng, has been applied for treating obesity, hypertension, cardiovascular disease, hyperlipidemia, and so on. The chlorogenic acids (CGAs) in Kuding tea have shown excellent antioxidative, antiobesity, anti-atherosclerotic and anticancer activities. Nevertheless, the chemical profiles of CGAs in Kuding tea have not been comprehensively studied yet, which hinders further quality control. In the present study, a sensitive ultra-high-performance liquid chromatography-diode array detection coupled with a linear ion trap-Orbitrap (UHPLC-DAD-LTQ-Orbitrap) method was established to screen and identify CGAs in Kuding tea. Six CGA standards were first analyzed in negative ion mode with a CID-MS/MS experiment and then the diagnostic product ions (DPIs) were summarized. According to the retention behavior in the RP-ODS column, accurate mass measurement, DPIs and relevant bibliography data, a total of 68 CGA candidates attributed to 12 categories were unambiguously or preliminarily screened and characterized within 18 min of chromatographic time. This was the first systematic report on the distribution of CGAs in Kuding tea. Meanwhile, the contents of 6 major CGAs in Kuding tea were also determined by the UHPLC-DAD method. All the results indicated that the established analytical method could be employed as an effective technique for the comprehensive and systematic characterization of CGAs and quality control of the botanic extracts or Chinese medicinal formulas that contain various CGAs. [ABSTRACT FROM AUTHOR]

With apparent advantages of the severalGHz license-free spectrums, 10Wmaximumtransmit power, and so forth, 60GHz wireless communication technology has become the first choice for Gbps level short-range wireless communications. This paper researches 60GHz wireless communications over the additive white Gaussian noise channel. Channel capacity with quadrature amplitude modulation (QAM) is investigated for the unlicensed 59-64GHz radio spectrum set aside by FCC. Moreover, the capacity with QAM is compared to that with phase shift keying (PSK). It is shown that QAM is capable of providing Gbps data rate and outperforms PSK especially when the modulation order is large. The results prove that QAM is an attractive scheme for 60GHz wireless communications. [ABSTRACT FROM AUTHOR]

Colorectal carcinomas are common in adults; however, they rarely occur in children. The present study reported the case of a colorectal carcinoma diagnosed as signet-ring cell carcinoma in a 9-year-old boy. The patient presented with acute intestinal obstruction symptoms, which persisted following 3 days of conservative treatment. The diagnosis was determined by emergency laparotomy and a mass was identified in the transverse colon proximal to the splenic flexure. Histological examination of the mass revealed signet-ring cell carcinoma. In addition, the present study aimed to discuss the diagnostic establishment and treatment of this rare disease in children. Due to the high mortality rate caused by delays in accurate diagnoses, signet-ring cell carcinoma in children promotes a specific diagnostic and surgical challenge. [ABSTRACT FROM AUTHOR]