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1.
Chemistry ; 30(9): e202303672, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-37985368

RESUMO

Scientists are increasingly paying attention to using theoretical design as a guide combined with modern in-situ characterization techniques to develop catalysts with high activity, low cost, and long-term life. The review discusses the progress of catalyst theoretical design and corresponding experiments based on three typical oxygen evolution catalytic mechanisms, including the adsorbate evolution, lattice oxygen-mediated, and unconventional bifunctional mechanisms. This work briefly describes the commonly used tools and descriptors in theory as well as the electrochemical techniques and characterizations in experiments. Our purpose is to sort out the ways to closely integrate the theoretical method and experimental verification from the perspective of reaction mechanism, and to provide some experience reference for the future development of theoretical tools and experimental technologies.

2.
Opt Express ; 31(19): 31610-31621, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710675

RESUMO

Optical vortex beams, with phase singularity characterized by a topological charge (TC), introduces a new dimension for optical communication, quantum information, and optical light manipulation. However, the evaluation of TCs after beam propagation remains a substantial challenge, impeding practical applications. Here, we introduce vortices in lateral arrays (VOILA), a novel spatial multiplexing approach that enables simultaneous transmission of a lateral array of multiple vortices. Leveraging advanced learning techniques, VOILA effectively decodes TCs, even in the presence of strong optical nonlinearities simulated experimentally. Notably, our approach achieves substantial improvements in single-shot bandwidth, surpassing single-vortex scheme by several orders of magnitude. Furthermore, our system exhibits precise fractional TC recognition in both linear and nonlinear regimes, providing possibilities for high-bandwidth communication. The capabilities of VOILA promise transformative contributions to optical information processing and structured light research, with significant potential for advancements in diverse fields.

3.
Environ Sci Technol ; 57(27): 10135-10146, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37316474

RESUMO

The electrocoagulation/ultrafiltration (ECUF) process is expected to address the issues of current wastewater increments and complex water reuse. However, the underlying mechanism associated with flocs remains unclear in the ECUF system, especially in the upgraded permanganate-bearing ECUF (PECUF) system. Herein, flocs and their formation, response to organic matter (OM), and interfacial features in the PECUF process were systematically explored. Results demonstrated that permanganate contributed to the rapid start-up of the coagulation process by forming MnO2 and blocking the ligand-metal charge transfer process between adsorbed Fe(II) and solid-phase Fe(III). The response of flocs to natural OM (NOM) exhibited obvious time- and particle size-dependent characteristics. Based on this, the optimal NOM adsorption window was found to be in the interval of 5-20 min, whereas the optimal NOM removal window was located at the 20-30 min interval. Furthermore, the extended Derjaguin-Landau-Verwey-Overbeek theory revealed the underlying principle of the PECUF module for optimizing UF performance. On the one hand, it reduced the inherent resistance of the cake layer by modifying the colloidal solution, which guaranteed a small drop (15%) in initial flux. On the other hand, it enhanced the repulsive force among suspended particles to achieve a long-term antifouling effect. This study may provide insights into the selection and performance control of on-demand assembly modules in decentralized water treatment systems.


Assuntos
Óxidos , Purificação da Água , Compostos de Manganês , Oxidantes , Compostos Férricos , Membranas Artificiais , Eletrocoagulação , Ultrafiltração/métodos , Purificação da Água/métodos
4.
Ann Vasc Surg ; 92: 118-123, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36481673

RESUMO

BACKGROUND: Carotid artery stenting (CAS) has emerged as a potential alternative for treating patients with extracranial cerebrovascular diseases. Contralateral carotid artery occlusion (CCO) occurs in approximately 2.3% to 25% of patients with carotid artery stenosis. However, the association of a CCO with long-term outcomes after CAS remains unclear. Here, we aimed to evaluate the perioperative and long-term recovery and safety of patients with CCO after receiving CAS. METHODS: We retrospectively collected the data of patients with CCO treated with CAS between 2010 and 2021. The primary end point was a nonfatal major stroke. The secondary end points included cerebral hemorrhage, nonfatal myocardial infarction, restenosis, acute renal insufficiency, stent-related complications, and death. Long-term outcomes were analyzed by Kaplan-Meier survival analysis using the following variables: symptomatic carotid stenosis, age, stent type, collateral flow status, and postdilation. RESULTS: Seventy one consecutive patients with CCO who underwent CAS were included in the study. Of these, 61 patients (86%) were followed up for 9-134 months, with an average of 63.3 ± 30.4 months. In the perioperative period, 2 patients (2.8%) experienced stroke and 1 patient (1.4%) died due to cerebral hemorrhage combined with cerebral hernia. During follow-up, 2 patients (3.3%) developed stroke at 4 and 6 months each after CAS and 6 patients (9.8%) died (2 patients died due to myocardial infarction and 4 patients died due to either severe liver failure, car accident, cervical fracture, or unknown cause). Kaplan-Meier survival analysis showed that symptomatic carotid stenosis, age, stent type, and postdilation were not associated with long-term stroke (P<0.05). The inadequate collateral flow group showed a higher stroke rate than the control group (P = 0.009). CONCLUSIONS: CAS is a safe and effective therapy for patients with CCO. Inadequate collateral flow is associated with a higher long-term rate of stroke. Our findings revealed that symptomatic carotid stenosis, age, stent type, and postdilation had no significant effect on outcome events after CAS.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/terapia , Estudos Retrospectivos , Resultado do Tratamento , Stents/efeitos adversos , Acidente Vascular Cerebral/etiologia , Endarterectomia das Carótidas/efeitos adversos , Hemorragia Cerebral/etiologia , Infarto do Miocárdio/etiologia , Artérias Carótidas/cirurgia , Fatores de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-37206625

RESUMO

Boron neutron capture therapy (BNCT) is a cellular-level hadron therapy achieving therapeutic effects via the synergistic action of multiple particles, including Lithium, alpha, proton, and photon. However, evaluating the relative biological effectiveness (RBE) in BNCT remains challenging. In this research, we performed a microdosimetric calculation for BNCT using the Monte Carlo track structure (MCTS) simulation toolkit, TOPAS-nBio. This paper reports the first attempt to derive the ionization cross-sections of low-energy (>0.025 MeV/u) Lithium for MCTS simulation based on the effective charge cross-section scalation method and phenomenological double-parameter modification. The fitting parameters λ1=1.101,λ2=3.486 were determined to reproduce the range and stopping power data from the ICRU report 73. Besides, the lineal energy spectra of charged particles in BNCT were calculated, and the influence of sensitive volume (SV) size was discussed. Condensed history simulation obtained similar results with MCTS when using Micron-SV while overestimating the lineal energy when using Nano-SV. Furthermore, we found that the microscopic boron distribution can significantly affect the lineal energy for Lithium, while the effect for alpha is minimal. Similar results to the published data by PHITS simulation were observed for the compound particles and monoenergetic protons when using micron-SV. Spectra with nano-SV reflected that the different track densities and absorbed doses in the nucleus together result in the dramatic difference in the macroscopic biological response of BPA and BSH. This work and the developed methodology could impact the research fields in BNCT where understanding radiation effects is crucial, such as the treatment planning system, source evaluation, and new boron drug development.

6.
Angew Chem Int Ed Engl ; 62(27): e202303482, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37129053

RESUMO

Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc2 (WO4 )3 :Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back-transfer the stored excitation energy to Ln3+ upon heating. Therefore, except routine anti-thermal quenching, thermally enhanced 415-fold downshifting and 405-fold upconversion luminescence are even obtained in Sc2 (WO4 )3 :Yb/Er, which has set a record of both the Yb3+ -Er3+ energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high-temperature luminescence.

7.
Opt Lett ; 47(3): 461-464, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103651

RESUMO

A deep learning channel estimation scheme in orthogonal frequency division multiplexing for X-ray communication (XCOM) is studied. The scheme uses simulated and detected data obtained with different working parameters and numbers of pilots as training and testing data, respectively, for the deep neural network (DNN) model. The bit-error-rate performance of the DNN model under various system operating parameters, numbers of pilot sequences, and channel obstructions is investigated separately. Experiment results showed that the deep-learning-based approach can address the distortion of the air-scintillator channel for XCOM, giving a performance comparable to those of least-squares and minimum-mean-square error estimation methods.


Assuntos
Aprendizado Profundo , Comunicação , Redes Neurais de Computação , Raios X
8.
Eur J Nucl Med Mol Imaging ; 49(8): 2618-2633, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35347438

RESUMO

PURPOSE: This study was to design and synthesize a novel bifunctional chelator, named Dar, primarily validated by conjugating to tumor targeting motifs, labeled with radiometals, and performed preclinical evaluation of tumor imaging and cancer therapy in murine tumor models. METHOD: The designed Dar was synthesized and characterized by X-ray crystallography, 1H/13C NMR, and mass spectrometry. Dar-PSMA-617 was conjugated and radiolabeled with 68Ga, 177Lu, and 89Zr. The in vivo behavior of 68 Ga/89Zr-labeled Dar-PSMA-617 were evaluated using micro-PET imaging and biodistribution from image quantitation and tissue radioactivity counting, with 68Ga/89Zr-labeled NOTA/DOTA/DFO-PSMA-617 analogs as controls, respectively. The [177Lu]-Dar-PSMA-617, with [177Lu]-DOTA-PSMA-617 as control, was evaluated in competitive cell uptake, tumor cell internalization, and efflux studies. The treatment efficacy of [177Lu]Lu-Dar-PSMA-617, with [177Lu]Lu-DOTA-PSMA-617 as control, was evaluated in PSMA-positive LNCaP tumor-bearing mice. In addition, the ability of Dar for radiolabeling nanobody was tested by conjugating Dar to KN035 nanobody. The resultant [89Zr]Zr-Dar-KN035 nanobody, with [89Zr]Zr-DFO-KN035 as control, was evaluated by micro-PET imaging and biodistribution in a mouse model bearing MC38&MC38-hPD-L1 colon cancer. RESULTS: 68Ga, 89Zr, and 177Lu-radiolabeled Dar-PSMA-617 complexes were able to be produced under mild condition with high radiochemical yield and purity successfully. [177Lu]Lu-Dar-PSMA-617 had higher cellular uptake yet similar internalization and efflux properties in LNCaP cells, as compared to [177Lu]Lu-DOTA-PSMA-617. Micro-PET images demonstrated significantly higher tumor uptake of [68Ga]Ga-Dar-PSMA-617, than that of the analog [68Ga]Ga-DOTA-PSMA-617. The tumor uptake values of [68Ga]Ga-Dar-PSMA-617 at multiple time points are comparable to that of [68Ga]Ga-NOTA-PSMA-617, although a higher and persistently prolonged kidney retention was resulted in during the study period. The Dar chelator can also successfully mediate the radiolabeling with 89Zr, while the resultant [89Zr]Zr-Dar-PSMA-617 demonstrated a similar biodistribution with [89Zr]Zr-DFO-PSMA-617 measured at 96 h p.i. The treatment with [177Lu]Lu-Dar-PSMA-617 significantly inhibited the tumor growth, showing much better efficacy than that of [177Lu]Lu-DOTA-PSMA-617 at the same injected radioactivity and mass dose. Dar was covalently linked to KN035 nanobody and enabled radiolabeling with 89Zr in high yield and radiochemical purity at room temperature. The resultant [89Zr]Zr-Dar-KN035, with [89Zr]Zr-DFO-KN035 as control, demonstrated superior tumor uptake and detection capability in PET imaging studies. CONCLUSION: The Dar, as a novel bifunctional chelator for medicating the labeling of radiometals onto tumor targeting carriers, was successfully synthesized and chemically characterized. Test radiolabeling, on PSMA-617 and a nanobody as tool targeting molecule carriers, demonstrated the Dar has potential as a universal bifunctional chelator for radiolabeling various radiometals (at least 68Ga, 177Lu, and 89Zr tested) commonly used for clinical imaging and therapy. Using a novel Dar chelator results in altered in vivo behavior of the carriers even though labeled with the same nuclide. This capability makes Dar an alternative to the existing choices for radiolabeling new carrier molecules with various radiometals, especially the radiometals with large radius.


Assuntos
Quelantes , Neoplasias , Animais , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Quelantes/química , Radioisótopos de Gálio , Humanos , Masculino , Camundongos , Tomografia por Emissão de Pósitrons/métodos , Medicina de Precisão , Compostos Radiofarmacêuticos/química , Distribuição Tecidual
9.
Opt Express ; 29(3): 3596-3608, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770956

RESUMO

We experimentally demonstrate an improved orthogonal frequency division multiplexing (OFDM) into the pulse width modulation (PWM) scheme for the X-ray communication (XCOM). The scheme is insensitive to the nonlinearity of the grid-controlled X-ray tube with switching 'on' and 'off' between two points. The dependence of this system's bit-error-rate (BER) performances on the data rates and the working parameters including the anode voltage and filament current of the grid-controlled X-ray tube are studied. The OFDM-PWM scheme reaches the data rate of 360 kbps at a BER of the forward error correction threshold of 3.8 × 10-3 over a 5 cm air channel. In addition, an experiment aided by density-based spatial clustering of applications with noise nonlinear compensation is carried out, and the results demonstrate the improvements in Q-factor by 0.62 dB.

10.
Nanotechnology ; 33(7)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34749351

RESUMO

Carbon nanotube (CNT) field-emission x-ray source has great potential in x-ray communication (XCOM) because of its controllable emission and instantaneous response. A novel voltage loading mode was proposed in this work to achieve high-frequency pulse x-ray emission. The characteristics of cathode current and pulse x-ray versus voltage, frequency, and pulse amplitude were studied, and XCOM data transmission experiment was carried out. Results showed that the CNT cold cathode x-ray source, as a communication signal source, could work in 1.05 MHz pulse emission frequency. When the grid voltage was higher than 470 V, the pulse x-ray waveform amplitude achieved peak, and the shape exhibited a pseudo square wave. The duty cycle of the x-ray waveform exceeded 50%, reaching 56% when the pulse frequency reached 1 MHz. In the XCOM data transmission experiment, the pulsed x-ray waveform was well consistent with the loading data signal voltage waveform under different pulse-emission frequencies. This work realized the x-ray high-frequency pulse emission of CNT cold cathode x-ray source and lays a foundation for the development and application of CNT cold cathode x-ray source in XCOM.

11.
Environ Sci Technol ; 55(2): 1270-1278, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33372511

RESUMO

The demand for thin-film composite (TFC) nanofiltration membranes with superior permeance and high rejection is gradually increasing for seawater desalination and brackish water softening. However, improving the membrane permeance remains a great challenge due to the formation of excrescent polyamide in the substrate pores and thick polyamide film. Herein, we fabricated a high-performance TFC nanofiltration membrane via a classical interfacial polymerization reaction on a two-dimensional lamellar layer of transition-metal carbides (MXene). The MXene layer promoted the absorption of the reactive monomer, and higher amine monomer concentration facilitated the self-sealing and self-termination of interfacial polymerization to generate a thinner outer polyamide film from 68 to 20 nm. The almost nonporous lamellar interface inhibited the formation of inner polyamide in the substrate pores. In addition, the MXene lamellar layer could be eliminated by mild oxidation after interfacial polymerization to avoid imparted additional hydraulic resistance. The resulting TFC membrane conferred a high rejection above 96% for Na2SO4 and excellent permeance of 45.7 L·m-2·h-1·bar-1, which was almost 4.5 times higher than that of the control membrane (10.2 L·m-2·h-1·bar-1). This research provides a feasible strategy for fabricating a high-performance nanofiltration membrane using two-dimensional nanosheets as a templated interface.


Assuntos
Membranas Artificiais , Nylons , Polimerização , Águas Salinas , Água
12.
Ann Vasc Surg ; 77: 101-108, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32339694

RESUMO

BACKGROUND: This study aimed to examine a quantitative method for evaluating calcification in failure in recanalization (FR) in endovascular treatment of superficial femoral artery (SFA) chronic total occlusion, and to investigate the possibility of using a formula to predict the incidence of true lumen recanalization (TR) in such cases. METHODS: Patients who met the inclusion criteria were retrospectively analyzed in our center from January 2012 to September 2017. A Calcification Lesion Analyzing and Scoring System (CLASS) was established to quantify the characteristics of calcification in SFA computed tomography slices, which were ranked as grade 1-4 and class A-E. Corresponding scores were obtained, and the Cumulative Calcification Score (CCSO) of occlusive SFA was calculated on the basis of CLASS. The factors correlating to FR and the formula for predicting TR were evaluated. RESULTS: A total of 215 patients were included in this study. There were 150 cases of TR and 65 cases of subintimal recanalization; 12 (5.6%) cases had FR. The maximum CLASS of occlusion was correlated with FR. Not only the formula including Trans-Atlantic Inter-Society Consensus II grade and CCSO but also the formula including occlusion length and CCSO predicted the incidence of TR well. CONCLUSIONS: The degree of the most severe calcification in occlusive lesions clearly affects success in recanalization. Two quantitative formulas that combine occlusion length or Trans-Atlantic Inter-Society Consensus II grade with CCSO can predict TR in endovascular treatment of SFA lesions with chronic total occlusion.


Assuntos
Procedimentos Endovasculares , Artéria Femoral , Doença Arterial Periférica/terapia , Calcificação Vascular/terapia , Idoso , Doença Crônica , Angiografia por Tomografia Computadorizada , Constrição Patológica , Técnicas de Apoio para a Decisão , Procedimentos Endovasculares/efeitos adversos , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/fisiopatologia , Grau de Desobstrução Vascular
13.
J Xray Sci Technol ; 29(4): 635-643, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935131

RESUMO

PURPOSE: This study aims to evaluate the planned dose of stereotactic body radiation therapy (SBRT) for treating early peripheral non-small cell lung cancer (NSCLC) using the non-coplanar radiation from Cyberknife and Varian linac. Moreover, this study investigates whether Cyberknife and Varian linac are qualified for non-coplanar radiation SBRT for treating early peripheral NSCLC, and which one is better for protecting organs at risk (OARs). METHODS: Retrospective analysis was performed based on the Cyberknife radiation treatment plans (RTPs) and Varian Eclipse RTPs of 10 patients diagnosed with early peripheral NSCLC. The dose distributions in the target and OARs were compared between the RTPs of Cyberknife and Varian Eclipse using Mim medical imaging software. RESULTS: For PTV, no significant difference in D98 and D95 between the Cyberknife and Eclipse was observed (t = -0.35, -1.67, P > 0.05). The homogeneity indexes (HIs) of Cyberknife plans are higher (t = 71.86, P < 0.05) than those of Eclipse plans. The V10, V15, V20, V25, V30 and Dmean of the lung with NSCLC and the V20 of the whole lung for Cyberknife were less than those for Eclipse (t = -4.73, -5.62, -7.75, -6.38, -6.89, -3.14, -7.09, respectively, P < 0.05). Cyberknife plans have smaller spinal cord Dmax, trachea Dmax, heart Dmax, chest wall Dmax (t = -2.49, -2.57, -3.71, -3.56, respectively, P < 0.05) and esophagus Dmax (t = -1.95, P > 0.05) than Varian Eclipse plans. CONCLUSION: To fulfill SBRT by non-coplanar radiation, Cyberknife is recommended for the institutions equipped with Cyberknife, while Varian linac can be applied for the institutions that have not adopted Cyberknife in clinical radiotherapy yet.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
14.
Environ Sci Technol ; 54(10): 6365-6374, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32324400

RESUMO

Traditional polyamide-based interfacial polymerized nanofiltration (NF) membranes exhibit upper bound features between water permeance and salt selectivity. Breaking the limits of the permeability and rejections of these composite NF membranes are highly desirable for water desalination. Herein, a high-performance NF membrane (TFC-P) was fabricated via interfacial polymerization on the poly(vinyl alcohol) (PVA) interlayered poly(ether sulfone) (PES) ultrafiltration support. Owing to the large surface area, great hydrophilicity, and high porosity of the PES-PVA support, a highly cross-linked polyamide separating layer was formed with a thickness of 9.6 nm, which was almost 90% thinner than that of the control membrane (TFC-C). In addition, the TFC-P possessed lower ζ-potential, smaller pore size, and greater surface area compared to that of the TFC-C, achieving an ultrahigh water permeance of 31.4 L m-2 h-1 bar-1 and a 99.4% Na2SO4 rejection. Importantly, the PVA interlayer strategy was further applied to a pilot NF production line and the fabricated membranes presented stable water flux and salt rejections as comparable to the lab-scaled membranes. The outstanding properties of the PVA-interlayered NF membranes highlight the feasibility of the fabrication method for practical applications, which provides a new avenue to develop robust polyamide-based NF desalination membranes for environmental water treatment.


Assuntos
Membranas Artificiais , Nylons , Interações Hidrofóbicas e Hidrofílicas , Álcool de Polivinil , Cloreto de Polivinila
15.
Environ Res ; 188: 109833, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32798951

RESUMO

Coagulation and adsorption are gradually adopted as pre-treatments to produce reclaimed potable water. However, previous researches on membrane fouling mechanisms were currently insufficient to minimize dual membrane fouling. This study aimed at investigating the effects of pre-coagulation and pre-adsorption on the removal performance and membrane fouling alleviation of dual membrane UF/NF process in treating secondary effluent from a wastewater treatment plant. The results indicated that both types of pretreatments conferred positive effects on organic membrane fouling removal of the UF process whereas diverse effects on NF process. Pre-coagulation could enhance the removal of nitrogen and phosphorus to contribute towards producing microbiologically-stable water. On the other hand, introduction of Al3+ reduced the removal efficiency of UF/NF systems on heavy metals. From the perspective of UF membrane fouling, two pretreatments employed could increase the flux of UF, but simultaneously aggravating irreversible membrane fouling. Hermia and Tansel models revealed an unstable cake filtration was caused by pre-coagulation and pre-adsorption. Both the models consistently demonstrated the rapid formation of cake filtration onto UF membrane surface. Interestingly, the powdered activated carbon (PAC) adsorption could significantly reduce cake layer fouling onto the surface of NF membrane, while pre-coagulation aggravated the NF fouling. These results are essential to developing robust, cost-effective and energy-efficient strategies based on membranes to produce reclaimed potable water.


Assuntos
Água Potável , Purificação da Água , Adsorção , Membranas Artificiais , Ultrafiltração , Águas Residuárias
16.
J Xray Sci Technol ; 28(2): 187-196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929130

RESUMO

BACKGROUND: Modern industrial facilities urgently need effective wireless communication technology to monitor instruments and equipment, but electromagnetic interference and physical shielding often exist in these fields, thereby preventing traditional communication methods from working correctly. OBJECTIVE: As a special wireless optical communication technology, X-ray communication (XCOM) is expected to solve the problem of signal transmission under this extreme condition. Our goal was to prove the feasibility of XCOM for signal transmission under metal barrier condition. METHODS: The Monte Carlo method was used to simulate the transmission characteristics of X-ray beam under metal barrier conditions, and the communication performance of XCOM was evaluated. Moreover, the experimental demonstration system of XCOM was developed to test the penetration and communication performance of XCOM under metal shield. RESULTS: X-ray with energy above 150 keV could achieve a bit error rate of less than 10-4 after passing through a 20 mm iron, whereas X-ray with energy above 250 keV could maintain excellent communication performance after passing through a 30 mm iron. The experimental test results were consistent with the theoretical calculation. CONCLUSIONS: As a new wireless optical communication technology, X-ray communication is expected to solve the problem of signal transmission under physical shielding conditions.


Assuntos
Desenho de Equipamento/métodos , Proteção Radiológica/instrumentação , Proteção Radiológica/métodos , Tecnologia sem Fio , Raios X , Estudos de Viabilidade , Método de Monte Carlo
17.
Blood ; 129(12): 1718-1728, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28096089

RESUMO

The combination of total lymphoid irradiation and anti-T-cell antibodies safely induces immune tolerance to combined hematopoietic cell and organ allografts in humans. Our mouse model required host natural killer T (NKT) cells to induce tolerance. Because NKT cells normally depend on signals from CD8+ dendritic cells (DCs) for their activation, we used the mouse model to test the hypothesis that, after lymphoid irradiation, host CD8+ DCs play a requisite role in tolerance induction through interactions with NKT cells. Selective deficiency of either CD8+ DCs or NKT cells abrogated chimerism and organ graft acceptance. After radiation, the CD8+ DCs increased expression of surface molecules required for NKT and apoptotic cell interactions and developed suppressive immune functions, including production of indoleamine 2,3-deoxygenase. Injection of naive mice with apoptotic spleen cells generated by irradiation led to DC changes similar to those induced by lymphoid radiation, suggesting that apoptotic body ingestion by CD8+ DCs initiates tolerance induction. Tolerogenic CD8+ DCs induced the development of tolerogenic NKT cells with a marked T helper 2 cell bias that, in turn, regulated the differentiation of the DCs and suppressed rejection of the transplants. Thus, reciprocal interactions between CD8+ DCs and invariant NKT cells are required for tolerance induction in this system that was translated into a successful clinical protocol.


Assuntos
Células Dendríticas/imunologia , Rejeição de Enxerto/prevenção & controle , Tolerância Imunológica , Células T Matadoras Naturais/imunologia , Animais , Transplante de Medula Óssea , Linfócitos T CD8-Positivos/imunologia , Comunicação Celular/imunologia , Rejeição de Enxerto/imunologia , Transplante de Coração , Camundongos
18.
J Radiol Prot ; 39(3): 838-853, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31195386

RESUMO

This study firstly explored the risks of secondary cancer in healthy organs of Chinese paediatric patients with brain tumours after boron neutron capture therapy (BNCT). Three neutron beam irradiation geometries (i.e. right lateral, top to bottom, posterior to anterior) were adopted in treating patients with brain tumours under the clinical environment of BNCT. The concerned organs in this study were those with high cancer morbidity in China (e.g. lung, liver and stomach). The equivalent doses for these organs were calculated using Monte Carlo and anthropomorphic paediatric phantoms with Chinese physiological features. The risk of secondary cancer, characterised by the lifetime attributable risk (LAR) factor given in the BEIR VII report, was compared among the three irradiation geometries. The results showed that the LAR was lower with the PA irradiation geometry than with the two other irradiation geometries when the 2 cm diameter tumour was at a depth of 6 cm on the right side of the brain. Under the PA irradiation geometry, the LAR in the organs increased with increasing tumour volume and depth because of the long irradiation time. As the patients aged from 10-15 years old, the LAR decreased, which was related to the increased patient height and shortened life expectancy. Female patients had a relatively higher risk of secondary cancer than male patients in this study, which could be due to the thinner body thickness and the weaker protective effect on the internal organs of the female patients. In conclusion, the risks of secondary cancer in organs were related to irradiation geometries, gender, and age, indicating that the risk of secondary cancer is a personalised parameter that needs to be evaluated before administering BNCT, especially in patients with large or deep tumours.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias Encefálicas/radioterapia , Neoplasias Induzidas por Radiação/etiologia , Segunda Neoplasia Primária/etiologia , Adolescente , Criança , China , Feminino , Humanos , Masculino , Modelos Anatômicos , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Medição de Risco
19.
Clin Immunol ; 187: 37-45, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29031828

RESUMO

There is significant debate regarding whether B cells and their antibodies contribute to effective anti-cancer immune responses. Here we show that patients with metastatic but non-progressing melanoma, lung adenocarcinoma, or renal cell carcinoma exhibited increased levels of blood plasmablasts. We used a cell-barcoding technology to sequence their plasmablast antibody repertoires, revealing clonal families of affinity matured B cells that exhibit progressive class switching and persistence over time. Anti-CTLA4 and other treatments were associated with further increases in somatic hypermutation and clonal family size. Recombinant antibodies from clonal families bound non-autologous tumor tissue and cell lines, and families possessing immunoglobulin paratope sequence motifs shared across patients exhibited increased rates of binding. We identified antibodies that caused regression of, and durable immunity toward, heterologous syngeneic tumors in mice. Our findings demonstrate convergent functional anti-tumor antibody responses targeting public tumor antigens, and provide an approach to identify antibodies with diagnostic or therapeutic utility.


Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos B/imunologia , Neoplasias/imunologia , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos , Sítios de Ligação de Anticorpos/imunologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/secundário , Progressão da Doença , Feminino , Humanos , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Melanoma/imunologia , Melanoma/secundário , Pessoa de Meia-Idade , Metástase Neoplásica , Plasmócitos/imunologia , Células Precursoras de Linfócitos B , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia
20.
J Environ Manage ; 209: 245-253, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29306141

RESUMO

To reduce fine particulate matter emission from coal burning sources especially fossil fuel fired energy generation facility is critical to improve air quality. Attapulgite suspension was attempted to spray in a 6 kW fluidized bed facility and reduce fine particulate matter emission during coal combustion. The key parameters such as attapulgite mass, flowrate and spraying zone were investigated to determine the optimal and critical conditions that influence fine particulate matter emission. Exciting results indicate that both fine particle number and mass concentrations are largely decreased due to the physical/chemical absorption with the suitable mass ratio of 3 wt%. The spray of attapulgite suspension in both dense bed and dilute bed effectively mitigates fine particle emission based on the agglomeration and absorption. The most excellent result is achieved at a flowrate of 38 ml/min in dense bed with particle number reduction up to 93.5% in PM2.5 (fine particles is equal to/less than 2.5 µm), 93.6% in PM1.0 (fine particles is equal to/less than 1.0 µm) and 93.7% in PM0.1 (fine particles is equal to/less than 0.1 µm), respectively. The work highlights the potential of spraying attapulgite suspension as an effective process to reduce fine particle emission during coal combustion in fluidized bed system.


Assuntos
Carvão Mineral , Compostos de Magnésio/análise , Compostos de Silício/análise , Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado
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