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1.
Materials (Basel) ; 17(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38612218

RESUMO

Replacing cement with industrial by-products is an important way to achieve carbon neutrality in the cement industry. The purpose of this study is to evaluate the effect of eggshell powder on cement hydration properties, and to evaluate its feasibility as a substitute for cement. The substitution rates of eggshell powder are 0%, 7.5%, and 15%. Studying the heat of hydration and macroscopic properties can yield the following results. First: The cumulative heat of hydration based on each gram of cementitious material falls as the eggshell powder content rises. This is a result of the eggshell powder's diluting action. However, the cumulative heat of hydration per gram of cement rises due to the nucleation effect of the eggshell powder. Second: The compressive strengths of ES0, ES7.5, and ES15 samples at 28 days of age are 54.8, 43.4, and 35.5 MPa, respectively. Eggshell powder has a greater negative impact on the compressive strength. The effect of eggshell powder on the speed and intensity of ultrasonic waves has a similar trend. Third: As the eggshell powder content increases, the resistivity gradually decreases. In addition, we also characterize the microscopic properties of the slurry with added eggshell powder. X-ray Diffraction (XRD) shows that, as the age increases from 1 day to 28 days, hemicaboaluminate transforms into monocaboaluminate. As the content of the eggshell powder increases, FTIR analysis finds a slight decrease in the content of CSH. Similarly, thermogravimetric (TG) results also show a decrease in the production of calcium hydroxide. Although the additional nucleation effect of eggshell powder promotes cement hydration and generates more portlandite, it cannot offset the loss of portlandite caused by the decrease in cement. Last: A numerical hydration model is presented for cement-eggshell powder binary blends. The parameters of the hydration model are determined based on hydration heat normalized by cement mass. Moreover, the hydration heat until 28 days is calculated using the proposed model. The strength development of all specimens and all test ages can be expressed as an exponential function of hydration heat.

2.
Health Econ Rev ; 14(1): 26, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564113

RESUMO

BACKGROUND: To estimate the long-term cost-effectiveness of once-weekly semaglutide versus sitagliptin as an add-on therapy for type 2 diabetes patients inadequately controlled on metformin in China, to better inform healthcare decision making. METHODS: The Cardiff diabetes model which is a Monte Carlo micro-simulation model was used to project short-term effects of once-weekly semaglutide versus sitagliptin into long-term outcomes. Short-term data of patient profiles and treatment effects were derived from the 30-week SUSTAIN China trial, in which 868 type 2 diabetes patients with a mean age of 53.1 years inadequately controlled on metformin were randomized to receive once-weekly semaglutide 0.5 mg, once-weekly semaglutide 1 mg, or sitagliptin 100 mg. Costs and quality-adjusted life years (QALYs) were estimated from a healthcare system perspective at a discount rate of 5%. Univariate sensitivity analysis, scenario analysis, and probabilistic sensitivity analysis were conducted to test the uncertainty. RESULTS: Over patients' lifetime projections, patients in both once-weekly semaglutide 0.5 mg and 1 mg arms predicted less incidences of most vascular complications, mortality, and hypoglycemia, and lower total costs compared with those in sitagliptin arm. For an individual patient, compared with sitagliptin, once-weekly semaglutide 0.5 mg conferred a small QALY improvement of 0.08 and a lower cost of $5173, while once-weekly semaglutide 1 mg generated an incremental QALY benefit of 0.12 and a lower cost of $7142, as an add-on to metformin. Therefore, both doses of once-weekly semaglutide were considered dominant versus sitagliptin with more QALY benefits at lower costs. CONCLUSION: Once-weekly semaglutide may represent a cost-effective add-on therapy alternative to sitagliptin for type 2 diabetes patients inadequately controlled on metformin in China.

3.
Nanoscale ; 16(18): 9136, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38661520

RESUMO

Expression of concern for 'Gadolinium embedded iron oxide nanoclusters as T1-T2 dual-modal MRI-visible vectors for safe and efficient siRNA delivery' by Xiaoyong Wang et al., Nanoscale, 2013, 5, 8098-8104, https://doi.org/10.1039/C3NR02797J.


Assuntos
Gadolínio , Imageamento por Ressonância Magnética , RNA Interferente Pequeno , RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo , Gadolínio/química , Humanos , Compostos Férricos/química , Meios de Contraste/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Animais
4.
Kidney Int ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38423183

RESUMO

Podocyte injury and loss are hallmarks of diabetic nephropathy (DN). However, the molecular mechanisms underlying these phenomena remain poorly understood. YAP (Yes-associated protein) is an important transcriptional coactivator that binds with various other transcription factors, including the TEAD family members (nuclear effectors of the Hippo pathway), that regulate cell proliferation, differentiation, and apoptosis. The present study found an increase in YAP phosphorylation at S127 of YAP and a reduction of nuclear YAP localization in podocytes of diabetic mouse and human kidneys, suggesting dysregulation of YAP may play a role in diabetic podocyte injury. Tamoxifen-inducible podocyte-specific Yap gene knockout mice (YappodKO) exhibited accelerated and worsened diabetic kidney injury. YAP inactivation decreased transcription factor WT1 expression with subsequent reduction of Tead1 and other well-known targets of WT1 in diabetic podocytes. Thus, our study not only sheds light on the pathophysiological roles of the Hippo pathway in diabetic podocyte injury but may also lead to the development of new therapeutic strategies to prevent and/or treat DN by targeting the Hippo signaling pathway.

5.
Nano Lett ; 24(7): 2299-2307, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38334593

RESUMO

Organic-inorganic hybrid perovskites have attracted tremendous attention owing to their fascinating optoelectronic properties. However, their poor air stability seriously hinders practical applications, which becomes more serious with thickness down to the nanoscale. Here we report a one-step vapor phase growth of HC(NH2)2PbBr3 (FAPbBr3) single-crystalline nanosheets of tunable size up to 50 µm and thickness down to 20 nm. The FAPbBr3 nanosheets demonstrate high stability for over months of exposure to air with no degradation in surface roughness and photoluminescence efficiency. Besides, the FAPbBr3 photodetectors exhibit superior overall performance as compared to previous devices based on nonlayered perovskite nanosheets, such as an ultralow dark current of 24 pA, an ultrahigh responsivity of 1033 A/W, an external quantum efficiency over 3000%, a rapid response time around 25 ms, and a high on/off ratio of 104. This work provides a strategy to tackle the challenges of hybrid perovskites toward integrated optoelectronics with requirements of nanoscale thickness, high stability, and excellent performance.

6.
BMC Med Imaging ; 24(1): 7, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166729

RESUMO

BACKGROUND: This study aimed to establish a predictive model to estimate the postoperative prognosis of patients with extrahepatic cholangiocarcinoma (ECC) based on preoperative clinical and MRI features. METHODS: A total of 104 patients with ECC confirmed by surgery and pathology were enrolled from January 2013 to July 2021, whose preoperative clinical, laboratory, and MRI data were retrospectively collected and examined, and the effects of clinical and imaging characteristics on overall survival (OS) were analyzed by constructing Cox proportional hazard regression models. A nomogram was constructed to predict OS, and calibration curves and time-dependent receiver operating characteristic (ROC) curves were employed to assess OS accuracy. RESULTS: Multivariate regression analyses revealed that gender, DBIL, ALT, GGT, tumor size, lesion's position, the signal intensity ratio of liver to paraspinal muscle (SIRLiver/Muscle), and the signal intensity ratio of spleen to paraspinal muscle (SIRSpleen/Muscle) on T2WI sequences were significantly associated with OS, and these variables were included in a nomogram. The concordance index of nomogram for predicting OS was 0.766, and the AUC values of the nomogram predicting 1-year and 2-year OS rates were 0.838 and 0.863, respectively. The calibration curve demonstrated good agreement between predicted and observed OS. 5-fold and 10-fold cross-validation show good stability of nomogram predictions. CONCLUSIONS: Our nomogram based on clinical, laboratory, and MRI features well predicted OS of ECC patients, and could be considered as a convenient and personalized prediction tool for clinicians to make decisions.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Nomogramas , Estudos Retrospectivos , Análise de Sobrevida , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Imageamento por Ressonância Magnética , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos
7.
Nanoscale ; 16(7): 3668-3675, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38289585

RESUMO

Owing to their superior charge retaining and transport characteristics, 2D transition metal dichalcogenides are investigated for practical applications in various memory-cell structures. Herein, we fabricated a quasi-one-terminal 2D memory cell by partially depositing a WSe2 monolayer on an Au electrode, which can be manipulated to achieve efficient charge injection upon the application or removal of external bias. Furthermore, the amount of charge carriers stored in the memory cell could be optically probed because of its close correlation with the fluorescence efficiency of WSe2, allowing us to achieve an electron retention time of ∼300 s at the cryogenic temperature of 4 K. Accordingly, the simplified device structure and the non-contact optical readout of the stored charge carriers present new research opportunities for 2D memory cells in terms of both fundamental mechanism studies and practical development for integrated nanophotonic devices.

8.
Chemistry ; 30(10): e202302948, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38171804

RESUMO

Platinum complexes are potential antitumor drugs in chemotherapy. Their impact on tumor treatment could be greatly strengthened by combining with immunotherapy. Increasing evidences indicate that the antitumor activity of platinum complexes is not limited to chemical killing effects, but also extends to immunomodulatory actions. This review introduced the general concept of chemoimmunotherapy and summarized the progress of platinum complexes as chemoimmunotherapeutic agents in recent years. Platinum complexes could be developed into inducers of immunogenic cell death, blockers of immune checkpoint, regulators of immune signaling pathway, and modulators of tumor immune microenvironment, etc. The synergy between chemotherapeutic and immunomodulatory effects reinforces the antitumor activity of platinum complexes, and helps them circumvent the drug resistance and systemic toxicity. The exploration of platinum complexes for chemoimmunotherapy may create new opportunities to revive the discovery of metal anticancer drugs.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Platina/uso terapêutico , Platina/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Imunoterapia , Microambiente Tumoral
9.
Food Chem ; 438: 138062, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38064793

RESUMO

This study used samples processed with an innovative manufacturing process to explore the dynamic changes of large-leaf yellow tea (LYT) in color, aroma, and taste substances, and the quality components were most significantly affected in the stages of first pile-yellowing (FP) and over-fired drying (TD). In this process, the moisture and temperature conditions caused chlorophyll degradation, Maillard reactions, caramelization reactions, and isomerization of phenolic substances, forming the quality of LYT. Specifically, chlorophyll degradation favored the formation of color quality; the taste quality was determined by the content of soluble sugars, amino acids, catechins, etc.; the aroma quality was dependent on the content changes of alcohols and aldehydes, as well as the increase of sweet and roasting aroma substances in the third drying stage. Additionally, twelve key aroma components, including linalool, (E)-ß-ionone, 2,3-diethyl-5-methyl-pyrazine, etc., were identified as contributors to revealing LYT rice crust-like and sweet aroma formation mechanism.


Assuntos
Camellia sinensis , Compostos Orgânicos Voláteis , Odorantes/análise , Chá/química , Camellia sinensis/química , Paladar , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos Voláteis/análise , Folhas de Planta/química , Clorofila/análise
10.
Endocrine ; 83(2): 502-510, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37715934

RESUMO

OBJECTIVE: To establish a prediction model for preoperatively predicting grade 1 and grade 2/3 tumors in patients with pancreatic neuroendocrine tumors (PNETs) based on 68Ga-DOTATATE PET/CT. METHODS: Clinical data of 41 patients with PNETs were included in this study. According to the pathological results, they were divided into grade 1 and grade 2/3. 68Ga-DOTATATE PET/CT images were collected within one month before surgery. The clinical risk factors and significant radiological features were filtered, and a clinical predictive model based on these clinical and radiological features was established. 3D slicer was used to extracted 107 radiomic features from the region of interest (ROI) of 68Ga-dotata PET/CT images. The Pearson correlation coefficient (PCC), recursive feature elimination (REF) based five-fold cross validation were adopted for the radiomic feature selection, and a radiomic score was computed subsequently. The comprehensive model combining the clinical risk factors and the rad-score was established as well as the nomogram. The performance of above clinical model and comprehensive model were evaluated and compared. RESULTS: Adjacent organ invasion, N staging, and M staging were the risk factors for PNET grading (p < 0.05). 12 optimal radiomic features (3 PET radiomic features, 9 CT radiomic features) were screen out. The clinical predictive model achieved an area under the curve (AUC) of 0.785. The comprehensive model has better predictive performance (AUC = 0.953). CONCLUSION: We proposed a comprehensive nomogram model based on 68Ga-DOTATATE PET/CT to predict grade 1 and grade 2/3 of PNETs and assist personalized clinical diagnosis and treatment plans for patients with PNETs.


Assuntos
Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Tomografia por Emissão de Pósitrons , Cintilografia , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tumores Neuroendócrinos/patologia , Radioisótopos de Gálio , Tomografia Computadorizada por Raios X , Neoplasias Pancreáticas/patologia
11.
Qual Life Res ; 33(3): 691-703, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38032396

RESUMO

PURPOSE: This study aimed to explore the effects of community-based home health care (HHC) on the physical and mental health of older adults with chronic diseases in China. METHODS: The study data were retrieved from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey. Ordinary least squares regression model was used to assess the effects of community-based HHC on the health. Entropy balancing was used to test the robustness of the regression results. RESULTS: A total of 5571 older adults with chronic diseases were included. The results showed that older adults who had received community-based HHC reported significantly better self-rated health (coefficient = 0.051, 95%CI [0.004, 0.098]), less physical discomfort (coefficient = - 0.021, 95%CI [- 0.042, - 0.001]), lower depression scores (coefficient = - 0.263, 95%CI [- 0.490, - 0.037]), and lower anxiety scores (coefficient = - 0.233, 95%CI [- 0.379, - 0.088]) compared with those who had not received community-based HHC. Overall, community-based HHC conferred greater positive effects on the health of rural older adults, older adults with multiple chronic diseases, and older adults with low incomes. CONCLUSION: Community-based HHC was beneficial for improving self-rated health and reducing physical discomfort, depression, and anxiety in older adults with chronic diseases, thus improving their quality of life. It is important to promote its development nationwide in China.


Assuntos
Serviços de Assistência Domiciliar , Saúde Mental , Humanos , Idoso , Qualidade de Vida/psicologia , Nível de Saúde , Doença Crônica , China
12.
Adv Mater ; 36(5): e2308032, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37994680

RESUMO

Under continuous light illumination, it is known that localized domains with segregated halide compositions form in semiconducting mixed-halide perovskites, thus severely limiting their optoelectronic applications due to the negative changes in bandgap energies and charge-carrier characteristics. Here mixed-halide perovskite CsPbBr1.2 I1.8 nanocrystals are deposited onto an indium tin oxide substrate, whose temperature can be rapidly changed by ≈10 °C in a few seconds by applying or removing an external voltage. Such a sudden temperature change induces a temporary transition of CsPbBr1.2 I1.8 nanocrystals from the segregated phase to the mixed phase, the latter of which can be permanently maintained when the light illumination is coupled with periodic heating cycles. These findings mark the emergence of a practical solution to the detrimental phase-segregation problem, given that a small temperature modulation is readily available in various fundamental studies and practical devices of mixed-halide perovskites.

13.
Food Chem ; 438: 137837, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37979270

RESUMO

Acidification of aroma-enhanced black tea during storage was studied. UPLC-Q-TOF/MS (Ultra Performance Liquid Chromatography and Quadrupole-Time of Flight Mass Spectrometer) and HPLC (High-Performance Liquid Chromatography) analysis of non-volatile substances and organic acids revealed a decrease of soluble sugars and amino acids in aroma-enhanced black tea, while an increase in organic acids such as oxalic acid, malic acid and quinic acid. Further in vitro experiments indicated that the acidification of aroma-enhanced tea during storage can be attributed to decomposition of sugars and amino acids by heating, oxidation of aromatic aldehydes. Meanwhile, the amino acids, catechins, soluble sugars and flavonoids that constitute the taste of black tea are further reduced, changing the taste composition of tea infusion and further increasing its acidity. This study revealed the reasons for black tea acidification during aroma enhancement and storage and provided a theoretical basis for improving black tea quality.


Assuntos
Camellia sinensis , Compostos Orgânicos Voláteis , Chá/química , Odorantes/análise , Temperatura , Camellia sinensis/química , Aminoácidos , Aminas/análise , Açúcares , Concentração de Íons de Hidrogênio , Compostos Orgânicos Voláteis/análise
14.
Angew Chem Int Ed Engl ; 63(9): e202317852, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38141033

RESUMO

One-unit-cell, single-crystal, hexagonal CuInP2 S6 atomically thin sheets of≈0.81 nm in thickness was successfully synthesized for photocatalytic reduction of CO2 . Exciting ethene (C2 H4 ) as the main product was dominantly generated with the yield-based selectivity reaching ≈56.4 %, and the electron-based selectivity as high as ≈74.6 %. The tandem synergistic effect of charge-enriched Cu-In dual sites confined on the lateral edge of the CuInP2 S6 monolayer (ML) is mainly responsible for efficient conversion and high selectivity of the C2 H4 product as the basal surface site of the ML, exposing S atoms, can not derive the CO2 photoreduction due to the high energy barrier for the proton-coupled electron transfer of CO2 into *COOH. The marginal In site of the ML preeminently targets CO2 conversion to *CO under light illumination, and the *CO then migrates to the neighbor Cu sites for the subsequent C-C coupling reaction into C2 H4 with thermodynamic and kinetic feasibility. Moreover, ultrathin structure of the ML also allows to shorten the transfer distance of charge carriers from the interior onto the surface, thus inhibiting electron-hole recombination and enabling more electrons to survive and accumulate on the exposed active sites for CO2 reduction.

15.
Materials (Basel) ; 16(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38138768

RESUMO

To make the sound absorber easy to fabricate and convenient for practical application, a modular composable acoustic metamaterial with multiple nonunique chambers (MCAM-MNCs) was proposed and investigated, which was divided into a front panel with the same perforated apertures and a rear chamber with a nonunique grouped cavity. Through the acoustic finite element simulation, the parametric studies of the diameter of aperture d, depth of chamber T0, and thickness of panel t0 were conducted, which could tune the sound absorption performances of MCAM-MNCs-1 and MCAM-MNCs-2 for the expected noise reduction effect. The effective sound absorption band of MCAM-MNCs-1 was 556 Hz (773-1329 Hz), 456 Hz (646-1102 Hz), and 387 Hz (564-951 Hz) for T = 30 mm, T = 40 mm, and T = 50 mm, respectively, and the corresponding average sound absorption coefficient was 0.8696, 0.8854, and 0.8916, accordingly, which exhibited excellent noise attenuation performance. The sound absorption mechanism of MCAM-MNCs was investigated by the distributions of the total sound energy density (TSED). The components used to assemble the MCAM-MNCs sample were fabricated by additive manufacturing, and its actual sound absorption coefficients were tested according to the transfer matrix method, which demonstrated its feasibility and promoted its actual application.

16.
Bioeng Transl Med ; 8(6): e10482, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023709

RESUMO

Melittin, the principal constituent in bee venom, is an attractive candidate for cancer therapy. However, its clinical applications are limited by hemolysis, nonspecific cytotoxicity, and rapid metabolism. Herein, a novel genetically engineered vesicular antibody-melittin (VAM) drug delivery platform was proposed and validated for targeted cancer combination therapy. VAM generated from the cellular plasma membrane was bio-synthetically fabricated, with the recombinant protein (hGC33 scFv-melittin) being harbored and displayed on the cell membrane. The bioactive and targetable nanomelittin conjugated by hGC33 scFv could be released in an MMP14-responsive manner at tumor sites, which reduced off-target toxicity, especially the hemolytic activity of melittin. Importantly, VAM could be loaded with small-molecule drugs or nanoparticles for combination therapy. Nanomelittin formed pores in membranes and disturbed phospholipid bilayers, which allowed the anticancer agents (i.e., chemotherapeutic drug doxorubicin and sonosensitizer purpurin 18 nanoparticles) co-delivered by VAM to penetrate deeper tumor sites, leading to synergistic therapeutic effects. In particular, the punching effect generated by sonodynamic therapy further improved the immunomodulatory effect of nanomelittin to activate the immune response. Taken together, our findings indicate that clinically translatable VAM-based strategies represent a universal, promising approach to multimodal synergetic cancer therapy.

17.
Biomater Sci ; 11(22): 7327-7338, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37847063

RESUMO

Local radio-therapy combined with immunotherapy has attracted great interest in controlling local tumors. In this study, we have developed membrane-cloaked manganese dioxide nanoparticles displaying anti-PD-L1 antibodies as targeted immuno-radio-enhancers. Mediated by anti-PD-L1 antibodies (aPD-L1) expressed on cell membranes, this kind of membrane-coated nanosystem can selectively deliver cytosine-phosphate-guanine (CpG)-loaded MnO2 nanoparticles (NPs) and induce systemic anti-tumor immunities, thereby achieving favorable immuno/radio-therapeutic outcomes. Through expressing various functional proteins onto cellular membranes, the new class of membrane-camouflaged nanovehicles can be endowed with a wide variety of artificial functionalities such as enzymatic catalytic capabilities and specific targeting. This versatile nanoplatform, in general, enables the targeted delivery of theranostics, opening a new avenue for personalized nanomedicine.


Assuntos
Nanopartículas , Neoplasias , Humanos , Compostos de Manganês/uso terapêutico , Nanomedicina , Óxidos/uso terapêutico , Neoplasias/tratamento farmacológico , Portadores de Fármacos/uso terapêutico , Imunoterapia , Linhagem Celular Tumoral
18.
Materials (Basel) ; 16(19)2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37834521

RESUMO

Blended cement is commonly used for producing sustainable concretes. This paper presents an experimental study and an optimization design of a low-CO2 quaternary binder containing calcined clay, slag, and limestone using the response surface method. First, a Box-Behnken design with three influencing factors and three levels was used for the combination design of the quaternary composite cement. The lower limit of the mineral admixtures was 0%. The upper limits of slag, calcined clay, and limestone powder were 30%, 20%, and 10%, respectively. The water-to-binder ratio (water/binder) was 0.5. Experimental works to examine workability and strength (at 3 and 28 days) were performed for the composite cement. The CO2 emissions were calculated considering binder compositions. A second-order polynomial regression was used to evaluate the experimental results. In addition, a low-CO2 optimization design was conducted for the composite cement using a composite desirability function. The objectives of the optimization design were the target 28-day strength (30, 35, 40, and 45 MPa), target workability (160 mm flow), and low CO2 emissions. The trends of the properties of optimal combinations were consistent with those in the test results. In summary, the proposed optimization design can be used for designing composite cement considering strength, workability, and ecological aspects.

19.
Eur J Med Res ; 28(1): 463, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37884978

RESUMO

BACKGROUND: A novel CT-linac (kilovolt fan-beam CT-linac) has been introduced into total marrow and lymphoid irradiation (TMLI) treatment. Its integrated kilovolt fan-beam CT (kV FBCT) can be used not only for image guidance (IGRT) but also to re-calculate the dose. PURPOSE: This study reported our clinical routine on performing TMIL treatment on the CT-linac, as well as dose distribution comparison between planned and re-calculated based on IGRT FBCT image sets. METHODS: 11 sets of data from 5 male and 6 female patients who had underwent the TMLI treatment with uRT-linac 506c were selected for this study. The planning target volumes consist of all skeletal bones exclusion of the mandible and lymphatic sanctuary sites. A planned dose of 10 Gy was prescribed to all skeletal bones exclusion of the mandible in two fractions and 12 Gy in two fractions was prescribed to lymphatic sanctuary sites. Each TMLI plan contained two sub-plans, one dynamic IMRT for the upper body and the other VMAT for the lower extremity. Two attempts were made to obtain homogeneous dose in the overlapping region, i.e., applying two plans with different isocenters for the treatment of two fractions, and using a dose gradient matching scheme. The CT scans, including planning CT and IGRT FBCT, were stitched to a whole body CT scan for dose distribution evaluation. RESULTS: The average beam-on time of Planupper is 30.6 min, ranging from 24.9 to 37.5 min, and the average beam-on time of Planlower is 6.3 min, ranging from 5.7 to 8.2 min. For the planned dose distribution, the 94.79% of the PTVbone is covered by the prescription dose of 10 Gy (V10), and the 94.68% of the PTVlymph is covered by the prescription dose of 12 Gy (V12). For the re-calculated dose distribution, the 92.17% of the PTVbone is covered by the prescription dose of 10 Gy (V10), and the 90.07% of the PTVlymph is covered by the prescription dose of 12 Gy (V12). The results showed that there is a significant difference (p < 0.05) between planning V10, V12 and delivery V10, V12. There is no significant difference (p > 0.05) between planned dose and re-calculated dose on selected organs, except for right lens (p < 0.05, Dmax). The actual delivered maximum dose of right lens is apparently larger than the planned dose of it. CONCLUSION: TMLI treatment can be performed on the CT-linac with clinical acceptable quality and high efficiency. Evaluation of the recalculated dose on IGRT FBCT suggests the treatment was delivered with adequate target coverage.


Assuntos
Radioterapia de Intensidade Modulada , Humanos , Masculino , Feminino , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Medula Óssea , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Irradiação Linfática , Tomografia Computadorizada por Raios X/métodos
20.
Nano Lett ; 23(21): 10089-10096, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37890167

RESUMO

An in-depth understanding of the structure-property relationships in semiconductor mixed-halide perovskites is critical for their potential applications in various light-absorbing and light-emitting optoelectronic devices. Here we show that during the crystal growth of mixed-halide CsPbBr1.2I1.8 nanocrystals (NCs), abundant Ruddlesden-Popper (RP) plane stacking faults are formed to release the lattice strain. These RP planes hinder the exchange of halide species across them, resulting in the presence of multiple nanodomains with discrete mixed-halide compositions inside a single CsPbBr1.2I1.8 NC. Photoluminescence peaks from these pre-segregated nanodomains, whose correlated intensity and wavelength variations signify the interactions of coupled quantum dots within a single CsPbBr1.2I1.8 NC, can be simultaneously resolved at cryogenic temperature. Our findings thus point to a fascinating scenario in which a semiconductor nanostructure can be further divided into multiple quantum-light sources, the interaction and manipulation of which will promote novel photophysics to facilitate their potential applications in quantum information technologies.

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