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1.
Opt Express ; 32(2): 1231-1245, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297679

RESUMO

Comprehensive optical imaging of the intensity, phase, and birefringent information of the biological sample is important because important physical or pathological changes always accompany the changes in multiple optical parameters. Current studies lack such a metric that can present the comprehensive optical property of the sample in one figure. In this paper, a polarization state synthesis tomography (PoST) method, which is based on the principle of polarization state coherent synthesis and demodulation, is proposed to achieve full-field tomographic imaging of the comprehensive information (i.e., intensity, phase, and birefringence) of the biological sample. In this method, the synthesis of the polarization state is achieved by the time-domain full-field low coherence interferometer, where the polarization states of the sample beam and the reference beam are set to be orthogonal for the synthesis of the polarization state. The synthesis of the polarization state enables two functions of the PoST system: (1) Depth information of the sample can be encoded by the synthesized polarization state because only when the optical path length difference between the two arms is within the coherence length, a new polarization state can be synthesized; (2) Since the scattering coefficient, refractive index and the birefringent property of the sample can modulate the intensity and phase of the sample beam, the synthesized polarization state is sensitive to all these three parameters and can provide the comprehensive optical information of the sample. In this work, the depth-resolved ability and the comprehensive optical imaging metric have been demonstrated by the standard samples and the onion cells, demonstrating the potential application value of this method for further investigation of the important physical or pathological process of the biological tissues.

2.
World J Surg ; 47(10): 2446-2456, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37249632

RESUMO

BACKGROUND: The omission of axillary lymph node dissection (ALND) in patients with breast cancer who have metastatic sentinel lymph nodes (SLNs) undergoing mastectomy remains controversial. This meta-analysis explored the clinicopathological factors affecting the selection of ALND and the influences of ALND on survival outcomes in patients receiving mastectomy with positive SLNs. METHODS: Eligible studies published prior to 31 December 2022 were selected by searching the Embase, Web of Science and PubMed databases. Pooled analyses were performed using the number of events for clinicopathological parameters and HRs with 95% CIs for survival outcomes including disease-free survival (DFS), overall survival (OS), distant recurrence-free survival (DRFS) and locoregional recurrence-free survival (LRFS). RESULTS: A total of 10 retrospective studies enrolling only breast cancer patients with limited SLN metastases (no more than 3 positive SLNs or micrometastatic SLNs) undergoing mastectomy were included. Performing ALND in mastectomy patients who had limited SLN metastases was significantly correlated with invasive ductal carcinomas, larger tumors, lymphovascular invasion, higher tumor grade, macrometastatic SLNs, more positive SLNs, extranodal extension, positive surgical margins, negative ER, administration of adjuvant chemotherapy and nonwhite race (P < 0.05). However, performing ALND did not result in significantly longer OS, DFS, LRFS or DRFS (P > 0.05) in these patients. CONCLUSION: The present meta-analysis indicated that ALND may be safely avoided in patients with breast cancer who had limited SLN metastases undergoing mastectomy. Further well-designed randomized clinical trials are warranted to validate our results.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Mastectomia , Biópsia de Linfonodo Sentinela , Estudos Retrospectivos , Metástase Linfática/patologia , Axila/patologia , Excisão de Linfonodo
3.
Ecotoxicol Environ Saf ; 266: 115608, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37856981

RESUMO

The saline, alkaline environment of arid soils is conducive to the diffusion of the metalloid arsenic (As). Desert plants in this area are of great ecological importance and practical value. However, there are few studies on the mechanism of arsenic action in desert plants. Therefore, in this study, Eremostachys moluccelloides Bunge was treated with different concentrations of As2O5 [As(V)] to analyze the physiological, biochemical, and transcriptomic changes of its roots and leaves and to explore the molecular mechanism of its response to As(Ⅴ) stress. The activities of catalase, superoxidase, peroxidase, and the contents of malondialdehyde and proline in roots and leaves first increased and then decreased under the As(Ⅴ) stress of different concentrations. The content of As was higher in roots than in leaves, and the As content was positively correlated with As(Ⅴ) stress concentration. In the differentially expressed gene analysis, the key enzymes of the oxidative stress response in roots and leaves were significantly enriched in the GO classification. In the KEGG pathway, genes related to the abscisic acid signal transduction pathway were co-enriched and up-regulated in roots and leaves. The related genes in the phenylpropanoid biosynthesis pathway were significantly enriched and down-regulated only in roots. In addition, the transcription factors NAC, HB-HD-ZIP, and NF-Y were up-regulated in roots and leaves. These results suggest that the higher the As(V) stress concentration, the more As is taken up by roots and leaves of E. molucelloides Bunge. In addition to causing greater oxidative damage, this may interfere with the production of secondary metabolites. Moreover, it may improve As(V) tolerance by regulating abscisic acid and transcription factors. The results will deepen our understanding of the molecular mechanism of As(Ⅴ) response in E. moluccelloides Bunge, lay the foundation for developing and applying desert plants, and provide new ideas for the phytoremediation of As pollution in arid areas.


Assuntos
Arsênio , Transcriptoma , Arsênio/análise , Ácido Abscísico/metabolismo , Perfilação da Expressão Gênica , Folhas de Planta/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
4.
Sensors (Basel) ; 20(5)2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32164220

RESUMO

Different from the traditional healthcare field, Medical Cyber Physical Systems (MCPS) rely more on wireless wearable devices and medical applications to provide better medical services. The secure storage and sharing of medical data are facing great challenges. Blockchain technology with decentralization, security, credibility and tamper-proof is an effective way to solve this problem. However, capacity limitation is one of the main reasons affecting the improvement of blockchain performance. Certificateless aggregation signature schemes can greatly tackle the difficulty of blockchain expansion. In this paper, we describe a two-layer system model in which medical records are stored off-blockchain and shared on-blockchain. Furthermore, a multi-trapdoor hash function is proposed. Based on the proposed multi-trapdoor hash function, we present a certificateless aggregate signature scheme for blockchain-based MCPS. The purpose is to realize the authentication of related medical staffs, medical equipment, and medical apps, ensure the integrity of medical records, and support the secure storage and sharing of medical information. The proposed scheme is highly computationally efficient because it does not use bilinear maps and exponential operations. Many certificateless aggregate signature schemes without bilinear maps in Internet of things (IoT) have been proposed in recent years, but they are not applied to the medical field, and they do not consider the security requirements of medical data. The proposed scheme in this paper has high computing and storage efficiency, while meeting the security requirements in MCPS.

5.
J Med Syst ; 44(2): 52, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915982

RESUMO

With the rapid development of technologies such as artificial intelligence, blockchain, cloud computing, and big data, Medical Cyber Physical Systems (MCPS) are increasingly demanding data security, while cloud storage solves the storage problem of complex medical data. However, it is difficult to realize data security sharing. The decentralization feature of blockchain is helpful to solve the problem that the secure authentication process is highly dependent on the trusted third party and implement data security transmission. In this paper, the blockchain technology is used to describe the security requirements in authentication process, and a network model of MCPS based on blockchain is proposed. Through analysis of medical data storage architecture, it can ensure that data can't be tampered and untrackable. In the security authentication phase, bilinear mapping and intractable problems can be used to solve the security threat in the authentication process of medical data providers and users. It can avoid the credibility problem of the trusted third party, and also can realize the ?thyc=10?>two-way authentication between the hospital and blockchain node. Then, BAN logic is used to analyze security protocols, and formal analysis and comparison of security protocols are also made. The results show that the MCPS based on blockchain not only realizes medical treatment data sharing, but also meet the various security requirements in the security authentication phase. In addition, the storage and computing overhead costs is ideal. Therefore, the proposed scheme is more suitable for secure sharing of medical big data.


Assuntos
Blockchain/normas , Segurança Computacional/normas , Troca de Informação em Saúde/normas , Confidencialidade , Humanos , Armazenamento e Recuperação da Informação/métodos
6.
Sensors (Basel) ; 19(19)2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31569570

RESUMO

With the rapid development of the Internet of Things (IoT), it becomes challenging to ensure its security. Identity authentication and integrity verification can be achieved by secure hash functions and digital signature algorithms for IoT applications. In order to solve the issues of bandwidth limitation and computational efficiency of secure communication in IoT applications, an aggregate signature scheme based on multi- trapdoor hash function is proposed in this paper. Firstly, to prevent key exposition, based on the elliptic curve discrete logarithm problem (ECDLP), we constructed a double trapdoor hash function (DTH) and proved its reliability. Secondly, the multi-trapdoor hash function (MTH) based on DTH is presented. Finally, an MTH-based aggregate signature scheme (MTH-AS) with constant signature length is proposed. Based on the assumption of ECDLP, the proposed scheme is proven unforgeable against adaptive chosen message attacks with the Forking Lemma. Different from the most signature schemes with bilinear mapping, the proposed scheme has higher computational efficiency and shorter aggregate signature length. Moreover, it is independent of the number of signers. Security analysis and performance evaluation has revealed that the proposed scheme is an ideal solution for secure IoT applications with limited computing power, storage capacity, or limited bandwidth, such as wireless sensor networks, vehicular ad hoc networks, or healthcare sensor networks.


Assuntos
Algoritmos , Segurança Computacional , Internet das Coisas , Privacidade , Redes de Comunicação de Computadores , Humanos
7.
J Psychiatr Res ; 178: 107-113, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39128219

RESUMO

In the field of autism spectrum disorder (ASD), research on functional connectivity between gray matter and white matter remains under-researched. To address this gap, this study innovatively introduced a nested cross-validation method that integrates gray-white matter functional connectivity with an F-Score algorithm. This method calculates the correlation based on signals extracted from functional magnetic resonance imaging data using gray matter and white matter brain region templates. After applying the method to a New York University Langone Medical Center dataset consisting of 55 individuals with high-functioning ASD and 52 healthy subjects, we achieved a classification accuracy of 72.94%. This study found abnormal functional connectivity, primarily involving the left anterior prefrontal cortex and right superior corona radiata, left retrosplenial cortex and left superior corona radiata, as well as the left ventral anterior cingulate cortex and body of corpus callosum. Besides, we discovered that these abnormal connections are closely related to social impairment and restrictive and repetitive behaviors in ASD. In conclusion, this study provides a gray-white matter functional connectivity perspective for the diagnosis and understanding of ASD.

8.
Ecotoxicol Environ Saf ; 88: 163-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23228465

RESUMO

Chromium (Cr) is a toxic metal that poses a great threat to aquatic ecosystems. Information is limited on coinstantaneous responses of photosystems I (PSI) and II (PSII) to Cr(VI) stress due to lack of instruments that can simultaneously measure PSI and PSII activities. In the present study, responses of quantum yields of energy conversion and electron transport rates of PSI and PSII in Microcystis aeruginosa cells to Cr(VI) stress were simultaneously analyzed by a DUAL-PAM-100 system. Quantum yield of cyclic electron flow (CEF) under Cr(VI) stress and its physiological role in alleviating toxicity of Cr(VI) were also analyzed. At 5 mg L(-1) Cr(VI), quantum yield and electron transport rate of PSII decreased significantly, and light-induced non-photochemical fluorescence quenching lost. Cr(VI) also inhibited efficiency of PSII to use energy under high light more than of PSI. PSII showed lower maximal electron transport rate and light adaptability than PSI. Electron transport rate of PSI was higher and decreased less than that of PSII, implying less sensitivity of PSI to high light and Cr(VI). Energy dissipation through non-light-induced non-photochemical fluorescence quenching increased with increasing Cr(VI) concentration. CEF was stimulated under Cr(VI) treatment and made a significant contribution to quantum yield and electron transport of PSI, which was essential for protection of PSI from stresses of Cr(VI) and high light.


Assuntos
Cromo/toxicidade , Microcystis/efeitos dos fármacos , Complexo de Proteína do Fotossistema I/fisiologia , Complexo de Proteína do Fotossistema II/fisiologia , Poluentes Químicos da Água/toxicidade , Clorofila/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Fluorescência , Luz , Microcystis/metabolismo
9.
J Hazard Mater ; 458: 131912, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356173

RESUMO

Efficient separation and enrichment of uranium from radioactive effluents is of strategic significance for sustainable development of nuclear energy and environmental protection. Macropore structure of adsorbent is conducive to accessibility of the pore and transport of the adsorbate during dynamic adsorption. However, the low specific surface area results in fewer ligand sites and subsequently reduces the adsorption capacity. Herein, we present a novel strategy for efficient dynamic uranium enrichment using polyphosphonate-segmented macroporous organosilicon frameworks (PMOFs). PMOFs are constructed through the copolymerization of diethyl vinylphosphonate and triethoxyvinylsilane, followed by hydrolysis and condensation of the oligomers. The introduction of polyphosphonate segments into the frameworks endows PMOFs with a macroporous structure (31 µm) and a high ligand content (up to 72 wt%). Consequently, the optimized PMOF-3 demonstrated an ultrahigh dynamic adsorption capacity of 114.8 mg/g among covalently conjugated silicon-based materials. Additionally, PMOF-3 achieves a high enrichment factor (120) in the dynamic enrichment of uranium on a fixed bed column, which can be in-situ regenerated with 1 M NaHCO3 as the eluent. This work presents a new strategy for efficient dynamic enrichment of nuclides, which can be extended to the separation of other specific pollutants, shedding new light on adsorbent design and technical innovation.

10.
ACS Appl Mater Interfaces ; 15(26): 31421-31429, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37349266

RESUMO

The capture of radioiodine is crucial for nuclear security and environmental protection due to its volatility and superior environmental fluidity. Herein, we propose a strategy of "temperature-dependent gate" based on a swellable conjugated microporous polymer (SCMP) to significantly improve the capture of volatile iodine. The SCMP is constructed via the Buchwald-Hartwig coupling reaction of building monomers containing amines. It possesses a hierarchical pore structure with restricted pores, which can be "opened" and "closed" by changing the temperature. By virtue of the thermal-responsive pore structure, it reaches adsorption equilibrium for iodine in 2 h with a capacity of 4.3 g g-1 at 90 °C and retains 92.8% adsorbed iodine at room temperature. The SCMP also exhibits a high adsorption capacity up to 3.5 g g-1 for dissolved iodine within 10 min, as well as good radiation resistance and high selectivity for iodine against moisture, VOCs, and HNO3 vapor. The mechanism is clarified for effective iodine capture and caging based on the relationship between temperature and the pore structure. This work develops not only a strategy to enhance the capture of gaseous and dissolved iodine but also a new adsorption mechanism for iodine capture, which can be extended to the separation and caging of resources or volatile pollutants in other fields.

11.
Sci Rep ; 13(1): 1555, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707665

RESUMO

Chlorella sp. TLD 6B, a microalgae growing in the Taklamakan Desert, Xinjiang of China, is a good model material for studying the physiological and environmental adaptation mechanisms of plants in their arid habitats, as its adaptation to the harsh desert environment has led to its strong resistance. However, when using real-time quantitative polymerase chain reaction (RT-qPCR) to analyze the gene expression of this algae under abiotic stress, it is essential to find the suitable endogenous reference genes so to obtain reliable results. This study assessed the expression stability of 9 endogenous reference genes of Chlorella sp. TLD 6B under four abiotic stresses (drought, salt, cold and heat). These genes were selected based on the analysis results calculated by the three algorithmic procedures of geNorm, NormFinder, and BestKeeper, which were ranked by refinder. Our research showed that 18S and GTP under drought stress, 18S and IDH under salt stress, CYP and 18S under cold stress, GTP and IDH under heat stress were the most stable endogenous reference genes. Moreover, UBC and 18S were the most suitable endogenous reference gene combinations for all samples. In contrast, GAPDH and α-TUB were the two least stable endogenous reference genes in all experimental samples. Additionally, the selected genes have been verified to be durable and reliable by detecting POD and PXG3 genes using above endogenous reference genes. The identification of reliable endogenous reference genes guarantees more accurate RT-qPCR quantification for Chlorella sp. TLD 6B, facilitating functional genomics studies of deserts Chlorella as well as the mining of resistance genes.


Assuntos
Chlorella , Chlorella/genética , Genes de Plantas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Resposta ao Choque Frio , Guanosina Trifosfato , Padrões de Referência , Perfilação da Expressão Gênica/métodos
12.
Innovation (Camb) ; 4(5): 100496, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37663934

RESUMO

The quantification of the extent and dynamics of land-use changes is a key metric employed to assess the progress toward several Sustainable Development Goals (SDGs) that form part of the United Nations 2030 Sustainable Development Agenda. In terms of anthropogenic factors threatening the conservation of heritage properties, such a metric aids in the assessment of achievements toward heritage sustainability solving the problem of insufficient data availability. Therefore, in this study, 589 cultural World Heritage List (WHL) properties from 115 countries were analyzed, encompassing globally distributed and statistically significant samples of "monuments and groups of buildings" (73.2%), "sites" (19.3%), and "cultural landscapes" (7.5%). Land-cover changes in the WHL properties between 2015 and 2020 were automatically extracted from big data collections of high-resolution satellite imagery accessed via Google Earth Engine using intelligent remote sensing classification. Sustainability indexes (SIs) were estimated for the protection zones of each property, and the results were employed, for the first time, to assess the progress of each country toward SDG Target 11.4. Despite the apparent advances in SIs (10.4%), most countries either exhibited steady (20.0%) or declining (69.6%) SIs due to limited cultural investigations and enhanced negative anthropogenic disturbances. This study confirms that land-cover changes are among serious threats for heritage conservation, with heritage in some countries wherein the need to address this threat is most crucial, and the proposed spatiotemporal monitoring approach is recommended.

13.
Environ Technol ; 43(19): 2990-2999, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33820487

RESUMO

A new type of photocatalysts, nanocrystalline titanium dioxide (TiO2) doped with Co and I, were synthesized and modified via the sol-gel method to enhance the utilization of visible light. Herein, mono- and co-doped TiO2 (i.e. Co-TiO2, I-TiO2, Co-I-TiO2) were employed as the photocatalysts to investigate the photocatalytic performance on gaseous benzene removal. The prepared photocatalysts were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET)-specific surface areas, Raman spectroscopy, UV-visible diffuse reflectance spectroscopy (UV-vis-DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and electrochemical impedance spectroscopy (EIS). Results indicated that both particle sizes and band gaps of TiO2 were significantly reduced by doping with Co/I. Also, the lattice defects and the specific surface areas of TiO2 were substantially augmented by adding Co/I because of the increase of oxygen vacancies, especially for Co-I-TiO2. Meanwhile, Co and I were distributed on the titanium base with the existence of multivalent states. The benzene treatment capacity of Co-I-TiO2, Co-TiO2, I-TiO2 and Pure TiO2 is 441.46, 424.36, 388.06, and 51.25 µgC6H6/(g·h), respectively. To sum up, photocatalytic degradation of gaseous benzene could be improved by doping with Co/I because of the extension of catalyst lifetime and light response range covering visible light.

14.
ACS Appl Mater Interfaces ; 14(7): 9408-9417, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35147033

RESUMO

Uranium extraction is highly challenging because of low uranium concentration, high salinity, and a large number of competing ions in different environments. The template strategy is developed to address the defect of poor selectivity, but the adsorption capacity is limited by cavity blocking during the preparation of materials. Herein, a two-dimensional (2D) imprinting strategy is adopted to design 2D imprinted networks with specific nanotraps for effective uranium capture. The imprinted networks are established through the condensation polymerization of uranyl complexes, which are formed by aromatic building units coordinating with uranyl ions on the equatorial plane. Different from traditional imprinting materials that contain many invalid cavities (buried cavities or unreleased cavities), the as-prepared adsorbents possess tailored 2D nanotraps, which are open and specific to uranyl. Thus, the optimized networks not only show excellent selectivity for uranium (Kd = 964,500 mL/g in multi-ion solution) and slight disturbance of high salinity but also possess an ultrahigh adsorption capacity of 1365.7 mg/g. In addition, this adsorbent shows a high extraction efficiency for uranium under a wide range of pH conditions and exhibits good regeneration performance. This work proposes a pioneering strategy of 2D imprinting networks to capture uranium specifically with high capacity and can be applied to material design in many other fields.

15.
Environ Sci Pollut Res Int ; 28(9): 11323-11332, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33118066

RESUMO

The strain SCPG-7 was isolated from saline soil in a cotton field. It is confirmed that the strain SCPG-7 is Pseudomonas sp. by means of the analysis of its phenotypic features and 16S rRNA sequence. SCPG-7 was capable of dissolving mineral tri-calcium phosphate (Ca3(PO4)2) and tri-magnesium phosphate (Mg3(PO4)2). In contrast, no showing iron phosphate (FePO4) or aluminum phosphate (AlPO4) solubilizing activities were detected by this experimental approach. The ratio of the dissolved P diameter to the colony diameter was 1.86. To study the phosphate dissolving mechanisms of the strain, we analyzed the changes of the pH value, the soluble phosphate content, the concentration of alkaline phosphatase, and the production of organic acid in the insoluble phosphate liquid medium. 2-keto-D-gluconicacid, α-ketoglutaric acid, succinic acid, etc. were characterized by LC-MS/MS in NBRIP medium. The concentration of 2-keto-D-gluconicacid increased to 88.6 mg/L after being cultured for 216 h. The strain decreased the pH value of the medium from 7.4 to 4.7 and the released soluble phosphate up to 516 mg/L, which proved the production of organic acids and alkaline phosphatase to be mechanism for solubilizing P. Under low phosphorus stress, Pseudomonas global regulatory protein PhoB regulates the transcription of the alkaline phosphatase gene. IAA and siderophore were secreted by SCPG-7. After treatment with SCPG-7, the individual plant height and dry weight of pepper increased by 23.3 and 31.2%, respectively, compared to the control group. The results show that the strain SCPG-7 has the potential to convert insoluble inorganic phosphorus to plant-available phosphorus. It can enhance soil phosphorus release through biological pathways, thereby increasing crop yield, and providing germplasm resources for the development of biological fertilizers.


Assuntos
Capsicum , Cromatografia Líquida , Fosfatos , RNA Ribossômico 16S , Microbiologia do Solo , Espectrometria de Massas em Tandem
16.
Natl Sci Rev ; 8(9): nwab123, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34691745

RESUMO

By analysing the technical advantages and characteristics of imaging radar in cultural heritage, we provide new insights for the future development of cutting-edge Digital Heritage approaches through technical integration and interdisciplinary synergy.

17.
Environ Sci Pollut Res Int ; 27(20): 25655-25663, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32356061

RESUMO

A system consisting of hydrogen peroxide/persulfate (H2O2/S2O82-) catalyzed by siderite was attempted to oxidize nine representative petroleum hydrocarbon compounds [benzene, toluene, ethylbenzene, m-xylene, p-xylene, o-xylene, 1,2,4-trimethylbenzene, methyl-tert-butyl ether, and naphthalene] that tend to persist in the environment. Oxidation under different siderite dosages, H2O2:S2O82- ratios, and pH conditions were investigated. Results indicated that oxidation rates increased from 1.21-4.62 to 1.77-8.94 d-1 as siderite increased from 0.16 to 0.48 g/40 mL (H2O2:Na2S2O8 = 5:1, initial pH = 3.0), except for naphthalene (decreased from 0.58 to 0.45 d-1 with increased siderite dosage). When the H2O2:S2O82- ratio was increased from 1:1 to 5:1 (siderite = 0.16 g, initial pH = 3.0), the oxidation rates increased from 0.02-0.73 to 0.33-2.19 d-1. However, as pH increased to > 5.5 (siderite = 0.16 g, H2O2:Na2S2O8 = 2.5:1), the oxidation rates of petroleum hydrocarbons decreased to 0.003-0.09 d-1, which was approximately 90% less than that at pH = 3.0. The partial correlations and principal component analysis of the experimental data were conducted. Overall, both siderite dosage and H2O2:S2O82- ratio correlated positively with oxidation efficiency. The oxidation potential by H2O2/S2O82- mixtures towards the target petroleum hydrocarbon compounds seemed to be more sensitive to pH conditions than to siderite dosages or H2O2:S2O82- ratios.


Assuntos
Petróleo , Poluentes Químicos da Água/análise , Carbonatos , Catálise , Compostos Férricos , Hidrocarbonetos , Peróxido de Hidrogênio , Oxirredução , Compostos de Sódio , Sulfatos
18.
Sensors (Basel) ; 9(1): 503-18, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22389613

RESUMO

The Interferometric Point Target Analysis (IPTA) technique and Advanced Synthetic Aperture Radar (ASAR) images acquired over Hong Kong from 2007-2008 were used to detect ground deformation in the urban area of Guangzhou city in South China. A ground deformation rate map with scattered distribution of point targets shows the maximum subsidence (rise) rate as high as -26 to -20 mma(-1) (16-21 mma(-1)), implying that the study area is an active zone for ground deformation. Based on the point target map, a contour ground deformation rate map is generated. The map shows three major subsidence zones located in the middle-west, the east, and the southwest of the study area, respectively. All the six ground collapse accidents that occurred in 2007-2008 fall within the subsidence zones, qualitatively validating the IPTA results. Ground subsidence and geological conditions on Datansha Island are examined. The results indicate that the local geological conditions, such as limestone Karst geomorphology as well as silt layers characterized by high water content, high void ratio, high compressibility, low bearing capacity and low shear strength, and underground engineering projects are responsible for ground subsidence and ground collapse accidents occurred there.

19.
J Breast Cancer ; 22(1): 131-140, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30941240

RESUMO

When faced with a case of bilateral breast cancer (BBC), understanding how to differentiate bilateral primary breast cancer from contralateral metastatic breast cancer is essential for treatment, but clear identification criteria have not been established to date. Diverse events play different roles in the therapy and prognosis of BBC; hence, it is of great significance to detect a more comprehensive and convincing technique to make an accurate differential diagnosis. We report a rare case of synchronous BBC in a 61-year-old Chinese woman. Based on her clinical and pathological features and the use of whole exome sequencing and cancer genome analysis, we concluded that the patient developed contralateral metastatic breast cancer which metastasized from left to right. Therefore, together with clinical, pathological and cancer genomics information, we could precisely define the origin and evolution of BBC.

20.
Materials (Basel) ; 12(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634680

RESUMO

Near- α titanium alloys have extensive applications in high temperature structural components of aircrafts. To manufacture complex-shaped titanium alloy panel parts with desired microstructure and good properties, an innovative low-cost hot stamping process for titanium alloy was studied in this paper. Firstly, a series of hot tensile tests and Scanning Electron Microscope (SEM) observations were performed to investigate hot deformation characteristics and identify typical microstructural evolutions. The optimal forming temperature range is determined to be from 750 °C to 900 °C for hot stamping of TA15. In addition, a unified mechanisms-based material model for TA15 titanium alloy based on the softening mechanisms of recrystallization and damage was established, which enables to precisely predict stress-strain behaviors and potentially to be implemented into Finite Element (FE) simulations for designing the reasonable processing window of structural parts for the aerospace industry.

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