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1.
Cytokine ; 179: 156618, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663252

RESUMO

BACKGROUND: Pleural biomarkers represent potential diagnostic tools for tuberculous pleural effusion (TPE) due to their advantages of low cost, short turnaround time, and less invasiveness. This study evaluated the diagnostic accuracy of two CXCR3 ligands, C-X-C motif chemokine ligand 9 (CXCL9) and CXCL11, for TPE. In addition, we investigated the cellular origins and biological roles of CXCL9 and CXCL11 in the development of TPE. METHODS: This double-blind study prospectively enrolled patients with undiagnosed pleural effusion from two centers (Hohhot and Changshu) in China. Pleural fluid on admission was obtained and levels of CXCL9 and CXCL11 were measured by an enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve and the decision curve analysis (DCA) were used to evaluate their diagnostic accuracy and net benefit, respectively. THP-1 cell-derived macrophages were treated with Bacillus Calmette-Guérin (BCG), and quantitative real-time PCR (qRT-PCR) and ELISA were used to determine the mRNA and protein levels of CXCL9 and CXCL11. The chemoattractant activities of CXCL9 and CXCL11 for T helper (Th) cells were analyzed by a transwell assay. RESULTS: One hundred and fifty-three (20 TPEs and 133 non-TPEs) patients were enrolled in the Hohhot Center, and 58 (13 TPEs and 45 non-TPEs) were enrolled in the Changshu Center. In both centers, we observed increased CXCL9 and CXCL11 in TPE patients. The areas under the ROC curves (AUCs) of pleural CXCL9 and CXCL11 in the Hohhot Center were 0.70 (95 % CI: 0.55-0.85) and 0.68 (95 % CI: 0.52-0.84), respectively. In the Changshu Center, the AUCs of CXCL9 and CXCL11 were 0.96 (95 % CI: 0.92-1.00) and 0.97 (95 % CI: 0.94-1.00), respectively. The AUCs of CXCL9 and CXCL11 decreased with the advancement of age. The decision curves of CXCL9 and CXCL11 showed net benefits in both centers. CXCL9 and CXCL11 were upregulated in BCG-treated macrophages. Pleural fluid from TPE and conditioned medium from BCG-treated macrophages were chemotactic for Th cells. Anti-CXCL9 or CXCL11 neutralizing antibodies could partly block the chemotactic activity. CONCLUSIONS: Pleural CXCL9 and CXCL11 are potential diagnostic markers for TPE, but their diagnostic accuracy is compromised in elderly patients. CXCL9 and CXCL11 can promote the migration of peripheral Th cells, thus representing a therapeutic target for the treatment of TPE.

2.
bioRxiv ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38645004

RESUMO

Interactions between biological systems and nanomaterials have become an important area of study due to the application of nanomaterials in medicine. In particular, the application of nanomaterials for cancer diagnosis or treatment presents a challenging opportunity due to the complex biology of this disease spanning multiple time and spatial scales. A system-level analysis would benefit from mathematical modeling and computational simulation to explore the interactions between anticancer drug-loaded nanoparticles (NPs), cells, and tissues, and the associated parameters driving this system and a patient's overall response. Although a number of models have explored these interactions in the past, few have focused on simulating individual cell-NP interactions. This study develops a multicellular agent-based model of cancer nanotherapy that simulates NP internalization, drug release within the cell cytoplasm, "inheritance" of NPs by daughter cells at cell division, cell pharmacodynamic response to the intracellular drug, and overall drug effect on tumor dynamics. A large-scale parallel computational framework is used to investigate the impact of pharmacokinetic design parameters (NP internalization rate, NP decay rate, anticancer drug release rate) and therapeutic strategies (NP doses and injection frequency) on the tumor dynamics. In particular, through the exploration of NP "inheritance" at cell division, the results indicate that cancer treatment may be improved when NPs are inherited at cell division for cytotoxic chemotherapy. Moreover, smaller dosage of cytostatic chemotherapy may also improve inhibition of tumor growth when cell division is not completely inhibited. This work suggests that slow delivery by "heritable" NPs can drive new dimensions of nanotherapy design for more sustained therapeutic response.

3.
Nat Commun ; 15(1): 3106, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600068

RESUMO

In the study, we report an in situ corrosion and mass transport monitoring method developed using a radionuclide tracing technique for the corrosion study of 316L stainless steel (316L SS) in a NaCl-MgCl2 eutectic molten salt natural circulation loop. This method involves cyclotron irradiation of a small tube section with 16 MeV protons, later welds at the hot leg of the molten salt flow loop, generating radionuclides 51Cr, 52Mn, and 56Co at the salt-alloy interface. By measuring the activity variations of these radionuclides at different sections along the loop, both the in situ monitoring of the corrosion attack depth of 316L SS and corrosion product transport and its precipitation in flowing NaCl-MgCl2 molten salt are achieved. While 316L SS is the focus of this study, the technique reported herein can be extended to other structural materials being used in a wide range of industrial applications.

4.
Opt Express ; 32(7): 11271-11280, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570978

RESUMO

The advent of optical metrology applications has necessitated the development of compact, reliable, and cost-effective picosecond lasers operating around 900 nm, specifically catering to the requirements of precise ranging. In response to this demand, our work introduces an innovative solution-an all-fiber, all-polarization-maintaining (PM) figure-9 mode-locked laser operating at 915 nm. The proposed figure-9 Nd-doped fiber laser has a 69.2 m long cavity length, strategically designed and optimized to yield pulses with a combination of high pulse energy and low repetition rate. The laser can generate 915 nm laser pulses with a pulse energy of 4.65 nJ, a pulse duration of 15.2 ps under the repetition rate of 3.05 MHz. The 1064 nm amplified spontaneous emission (ASE) is deliberately filtered out, in order to prevent parasitic lasing and increase the spectral proportion of the 915 nm laser. The all-PM fiber configuration of this laser imparts exceptional mode-locking performance and environmental robustness, which is confirmed by long-term output power and spectral stability test. This compact and long-term reliable fiber laser could be a promising light source for applications like inter-satellite ranging.

5.
Ann Med ; 56(1): 2329132, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38608646

RESUMO

Myeloid neoplasms post cytotoxic therapy (MN-pCT) are a category includes AML, MDS, and MDS/MPN arising in patients exposed to cytotoxic (DNA-damaging) therapy for an unrelated condition in 2022 version World Health Organization (WHO) classification. With improved survival of patients with tumors, the incidence of MN-pCT after chemotherapy and/or radiation therapy among patients with tumors has gradually risen. However, the outcome of MN-pCT is poorer than that of primary myeloid neoplasms. This review summarizes the current understanding based on existing research, as a foundation for further research on MN-pCT.


Assuntos
Leucemia Mieloide Aguda , Humanos , Prognóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/epidemiologia
6.
J Med Case Rep ; 18(1): 207, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38610054

RESUMO

BACKGROUND: Total pelvic exenteration is the ultimate solution for rectovesicovaginal fistula caused by radiation therapy, yet total pelvic exenteration frequently causes intraoperative complications and postoperative complications. These complications are responsible for the dysfunction of lower extremities, impaired quality of life, and even the high long-term morbidity rate, thus multidisciplinary cooperation and early intervention for prevention of complications are necessary. Physical therapy was found to reduce the postoperative complications and promote rehabilitation, yet the effect on how physiotherapy prevents and treats complications after total pelvic exenteration and pelvic lymphadenectomy remains unclear. CASE PRESENTATION: A 50-year-old Chinese woman gradually developed perianal and pelvic floor pain and discomfort, right lower limb numbness, and involuntary vaginal discharge owing to recurrence and metastasis of cervical cancer more than half a year ago. Diagnosed as rectovesicovaginal fistula caused by radiation, she received total pelvic exenteration and subsequently developed severe lower limb edema, swelling pain, obturator nerve injury, and motor dysfunction. The patient was referred to a physiotherapist who performed rehabilitation evaluation and found edema in both lower extremities, right inguinal region pain (numeric pain rate scale 5/10), decreased temperature sensation and light touch in the medial thigh of the right lower limb, decreased right hip adductor muscle strength (manual muscle test 1/5) and right hip flexor muscle strength (manual muscle test 1/5), inability actively to adduct and flex the right hip with knee extension, low de Morton mobility Index score (0/100), and low Modified Barthel Index score (35/100). Routine physiotherapy was performed in 2 weeks, including therapeutic exercises, mechanical stimulation and electrical stimulation as well as manual therapy. The outcomes showed that physiotherapy significantly reduced lower limb pain and swelling, and improved hip range of motion, motor function, and activities of daily living, but still did not prevent thrombosis. CONCLUSION: Standardized physical therapy demonstrates the effect on postoperative complications after total pelvic exenteration and pelvic lymphadenectomy. This supports the necessity of multidisciplinary cooperation and early physiotherapy intervention. Further research is needed to determine the causes of thrombosis after standardized intervention, and more randomized controlled trials are needed to investigate the efficacy of physical therapy after total pelvic exenteration.


Assuntos
Exenteração Pélvica , Trombose , Neoplasias do Colo do Útero , Feminino , Humanos , Pessoa de Meia-Idade , Atividades Cotidianas , Qualidade de Vida , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Extremidade Inferior , Modalidades de Fisioterapia , Dor Pélvica , Edema , Complicações Pós-Operatórias/terapia
7.
Adv Mater ; : e2402575, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38631046

RESUMO

Organic photovoltaic (OPV) technology holds tremendous promise as a sustainable power source for underwater off-grid systems. However, research on underwater OPV cells is relatively scarce. Here, this gap is addressed by focusing on the exploration and development of OPV cells specifically designed for underwater applications. An acceptor, named ITO-4Cl, with excellent water resistance, is rationally designed and synthesized. Benefiting from its low energetic disorder and an absorption spectrum well-suited to the underwater environment, the ITO-4Cl-based OPV cell achieves an unprecedented power conversion efficiency (PCE) of over 25.6% at a water depth of 1 m. Additionally, under 660 nm laser irradiation, the cell demonstrates a notable PCE of 31.6%, indicating its potential for underwater wireless energy transfer. Due to the mitigation of thermal effects from solar irradiation, the lifetime of the ITO-4Cl-based OPV cell exceeds 7000 h. Additionally, a flexible OPV cell is fabricated that maintains its initial PCE even under exposure to high pressures of 5 MPa. A 32.5 cm2 flexible module achieves an excellent PCE of 17%. This work fosters a deeper understanding of underwater OPV cells and highlights the promising prospects of OPV cells for underwater applications.

8.
Oncogene ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594504

RESUMO

Ferroptosis has been demonstrated a promising way to counteract chemoresistance of multiple myeloma (MM), however, roles and mechanism of bone marrow stromal cells (BMSCs) in regulating ferroptosis of MM cells remain elusive. Here, we uncovered that MM cells were more susceptible to ferroptotic induction under the interaction of BMSCs using in vitro and in vivo models. Mechanistically, BMSCs elevated the iron level in MM cells, thereby activating the steroid biosynthesis pathway, especially the production of lanosterol, a major source of reactive oxygen species (ROS) in MM cells. We discovered that direct coupling of CD40 ligand and CD40 receptor constituted the key signaling pathway governing lanosterol biosynthesis, and disruption of CD40/CD40L interaction using an anti-CD40 neutralizing antibody or conditional depletion of Cd40l in BMSCs successfully eliminated the iron level and lanosterol production of MM cells localized in the Vk*MYC Vk12653 or NSG mouse models. Our study deciphers the mechanism of BMSCs dictating ferroptosis of MM cells and highlights the therapeutic potential of non-apoptosis strategies for managing refractory or relapsed MM patients.

9.
Gland Surg ; 13(3): 281-296, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38601282

RESUMO

Background: Accurate preoperative assessment of tumor size is important in developing a surgical plan for breast cancer. The purpose of this study was to evaluate the accuracy of cone-beam breast computed tomography (CBBCT) and magnetic resonance imaging (MRI) in the assessment of tumor size and to analyze the factors influencing the discordance. Methods: In this retrospective study, patients with breast cancer who underwent preoperative contrast-enhanced CBBCT (CE-CBBCT) and dynamic contrast-enhanced MRI (DCE-MRI) and received a complete pathologic diagnosis from August 2020 to December 2021 were included, using the pathological result as the gold standard. Two radiologists assessed the CBBCT and MRI features and measured the tumor size with a 2-week washout period. Intraclass correlation coefficient (ICC) and Bland-Altman analyses were used to assess inter-observer reproducibility and agreement based on CBBCT, MRI and pathology. Univariate analyses of differences in clinical, pathological and CBBCT/MRI features between the concordant and discordant groups was performed using the t-test, Mann-Whitney U-test, Chi-squared test and Fisher's exact test. Multivariate analyses were used to identify factors associated with discordance of CBBCT/MRI with pathology. Results: A total of 115 female breast cancer patients (115 lesions) were included. All patients had a single malignant tumor of the unilateral breast. The reproducibility and the agreement ranged from moderate to excellent (ICC =0.607-0.983). Receiver operating characteristic (ROC) analyses showed that the cut-off values of CBBCT-pathology and MRI-pathology discordance were 2.25 and 2.65 cm, respectively. CBBCT/MRI-pathology concordance was significantly associated with the extent of pathology, lesion type, presence of calcification, human epidermal growth factor receptor 2 (HER2) status and fatty infiltration (P<0.05). In lesions containing calcification, the difference of CBBCT-pathology was significantly smaller than MRI-pathology (P=0.021). Non-mass enhancement (NME) was the main predictor of CBBCT- or MRI-pathology discordance [odds ratio (OR) =3.293-6.469, P<0.05], and HER2 positivity was a predictor of CBBCT-pathology discordance (OR =3.514, P=0.019). Conclusions: CBBCT and MRI have comparable accuracy in measurement of tumor size, and CBBCT is advantageous in assessing the size of calcified lesions. NME and HER2 positivity are significant predictors of CBBCT-pathology discordance. This suggests that CBBCT might serve as an alternative imaging technique to assess tumor size when patients do not tolerate MRI.

10.
Surg Innov ; 31(3): 286-290, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38444075

RESUMO

BACKGROUND: Although the technique of single-incision laparoscopic cholecystectomy (SILC) has improved remarkably, problems such as limited exposure and instrument collision persist. We describe a new SILC technique that uses a set of specially-designed needle instruments. METHODS: Fifty-six patients with benign gallbladder disease underwent SILC using the newly-designed needle assembly instruments (NAIs). The NAIs comprise an needle assembly exposing hook for operative field exposure and an needle assembly electrocoagulation hook for dissection. During the operation, the NAIs were assembled and disassembled before and after gallbladder removal within the abdominal cavity. The operative efficacy and postoperative complications of this procedure were evaluated. RESULTS: SILC was completed successfully in 52 cases, and four cases (7.14%) required an additional trocar. There were no conversions to open surgery. The mean operative time was 48.2 ± 21.8 min, and the mean operative bleeding volume was 10.5 ± 12.5 mL. Minor postoperative complications occurred in 3 cases, including 2 cases of localized fluid accumulation in the abdominal cavity and 1 case of pulmonary infection, and all of them recovered after conservative treatment. There was no occurrence of bile leak, abdominal bleeding, bile duct injury and incisional hernia. The medical cost of each case was saved by approximately $200. The abdominal scars produced by the needle instruments were negligible. CONCLUSION: NAIs can make SILC safer, more convenient, and less expensive.


Assuntos
Colecistectomia Laparoscópica , Agulhas , Humanos , Colecistectomia Laparoscópica/instrumentação , Colecistectomia Laparoscópica/métodos , Feminino , Pessoa de Meia-Idade , Masculino , Adulto , Idoso , Doenças da Vesícula Biliar/cirurgia , Desenho de Equipamento , Complicações Pós-Operatórias , Resultado do Tratamento , Duração da Cirurgia
11.
Dalton Trans ; 53(16): 6965-6973, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38546786

RESUMO

Many diseases are due to bacterial infections, which are treated by penicillin. Existing methods for penicillin detection have relatively high requirements for sample storage and processing, personnel professionalism, and instruments. Herein, water-soluble N-C quantum dots (QDs) from wheat straw were synthesized in a green way by using an efficient and simple method. The N-C QDs were modified with an imprinted layer by a gel-sol method. Penicillin selectively quenched the fluorescence emission of N-C QDs@MIP, and a linear relationship was obtained in the concentration range of 1.0 × 10-6-15.2 × 10-6 mol L-1. The reliability of the sensor in real sample analysis was satisfactory with results in the range of 93.6%-100%, and the sensor showed good reproducibility and long-term stability. The study provides a simple strategy to fabricate N-C QDs@MIP with a highly selective recognition ability and opens an avenue to develop highly efficient sensing probes for the detection of antibiotics in biological applications.

12.
Sci Total Environ ; 924: 171549, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38467260

RESUMO

In the multifaceted realm of environmental governance, emphasizing public environmental participation as an informal regulatory mechanism, alongside the influence of formal governmental environmental regulation on regional carbon emissions, contributes to providing empirical evidence and policy insights for China's "dual­carbon target" action plan. Using data from 282 prefecture-level cities in China from 2011 to 2020, this research develops an analytical framework for urban carbon emissions encompassing public environmental concern, environmental regulation, green finance, and industrial agglomeration. And through an amalgamation of theoretical insights and empirical validation, the study elucidates the mechanisms by which public environmental concern impact urban carbon emissions. It further delves into the mediating role of environmental regulation and the moderating effects of green finance and industrial agglomeration. It reveals that: (1) Public environmental concern significantly reduces urban carbon emissions, particularly in northern cities, non-environmental protection key cities, and resource regeneration cities. And this suppressive influence is markedly more potent via mobile platforms compared to PC channels; (2) Environmental regulation serves as a partially mediating role between public environmental concern and urban carbon emissions, suggesting that public environmental concern reduces emissions by amplifying governmental environmental oversight; (3) Both green finance and industrial agglomeration play a positive moderating role on the effect of public environmental concern in reducing urban carbon emissions.

13.
J Am Chem Soc ; 146(13): 9205-9215, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38523309

RESUMO

The nonfused thiophene-benzene-thiophene (TBT) unit offers advantages in obtaining low-cost organic photovoltaic (OPV) materials due to its simple structure. However, OPV cells, including TBT-based acceptors, exhibit significantly lower energy conversion efficiencies. Here, we introduce a novel approach involving the design and synthesis of three TBT-based acceptors by substituting different position-branched side chains on the TBT unit. In comparison to TBT-10 and TBT-11, TBT-13, which exclusively incorporates α-position branched side chains with a large steric hindrance, demonstrates a more planar and stable conformation. When blended with the donor PBQx-TF, TBT-13-based blend film achieves favorable π-π stacking and aggregation characteristics, resulting in excellent charge transfer performance in the corresponding device. Due to the simultaneous enhancements in short-circuit current density and fill factor, the TBT-13-based OPV cell obtains an outstanding efficiency of 16.1%, marking the highest value for the cells based on fully nonfused acceptors. Our work provides a practical molecular design strategy for high-performance and low-cost OPV materials.

14.
Chem Commun (Camb) ; 60(25): 3421-3424, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38441282

RESUMO

Chiral bipolar hosts of (R/S)-L-2mCPCN are synthesized, which show high singlet/triplet energy levels and clear circularly polarized luminescence. Employing racemic phosphorescent and TADF materials as emitting guest molecules, solution-processable CP-OLEDs based on such chiral hosts are obtained with an EQEmax of 10.7% and |gEL| values of 5.0 × 10-3.

15.
Sci Total Environ ; 923: 171402, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38431176

RESUMO

China has a large fastest-aging population, which would reshape household consumption patterns and influence global CO2 emissions. This study examines global CO2 emissions driven by household consumption (i.e., household carbon footprints, HCFs) of 34 age groups in China's 30 provinces and uncovers relevant socioeconomic influencing factors. Results show that China's population aging (i.e., the proportion of the elderly population) is conducive to global CO2 emission reduction during 2011-2014. This trend is mainly due to the relatively lower per capita HCFs of the elderly (1.7 t in 2014). In contrast, the per capita HCFs of the youth group are higher (3.3 t in 2014), mainly affected by the large expenditure on residence and transportation & communication. In addition, the HCFs of all age groups have increased during 2011-2014. Per capita expenditure is the most significant driver of this increase. The decline in CO2 emission intensity makes the largest contribution to reducing the HCFs of the youth group. For the aged group, expenditure structure change is the largest contributor to HCFs reduction. These findings reveal the differentiated impacts of China's household consumption by age on global CO2 emissions. This study lays the scientific foundation for deriving amelioration policies and achieving emission reduction targets in the process of population aging.


Assuntos
Dióxido de Carbono , Pegada de Carbono , Idoso , Humanos , Adolescente , Dióxido de Carbono/análise , China , Fatores Socioeconômicos , Desenvolvimento Econômico , Carbono
16.
Adv Mater ; : e2400181, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419474

RESUMO

Recent electronics-tissues biointefacing technology has offered unprecedented opportunities for long-term disease diagnosis and treatment. It remains a grand challenge to robustly anchor the pressure sensing bioelectronics onto specific organs, since the periodically-varying stress generated by normal biological processes may pose high risk of interfacial failures. Here, a general yet reliable approach is reported to achieve the robust hydrogel interface between wireless pressure sensor and biological tissues/organs, featuring highly desirable mechanical compliance and swelling resistance, despite the direct contact with biofluids and dynamic conditions. The sensor is operated wirelessly through inductive coupling, characterizing minimal hysteresis, fast response times, excellent stability, and robustness, thus allowing for easy handling and eliminating the necessity for surgical extraction after a functional period. The operation of the wireless sensor has been demonstrated with a custom-made pressure sensing model and in vivo intracranial pressure monitoring in rats. This technology may be advantageous in real-time post-operative monitoring of various biological inner pressures after the reconstructive surgery, thus guaranteeing the timely treatment of lethal diseases.

17.
Opt Lett ; 49(4): 989-992, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359243

RESUMO

We demonstrated an efficient way to enhance and flatten the emission cross sections of Er3+ ions at the L-band in the silicate fiber amplifier by increasing Mg2+ (up to 22.5 mol%) with high field strength. High values of Er3+ concentration, lifetime, and L-band emission cross section were achieved in our silicate fibers. Particularly, the flatness at the L-band was achieved to be 0.8 dB, and a high gain coefficient at 1625 nm (4.7 dB/m) was demonstrated by pumping meter-scale Er-silicate fibers. The as-prepared Er-silicate fibers are attractive for the L-band fiber amplifier.

18.
ACS Appl Mater Interfaces ; 16(11): 13763-13772, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38379180

RESUMO

Although significant advancements have been achieved in lead-tin (Pb-Sn) alloyed perovskite solar cells (PSCs), their power conversion efficiency (PCE) remains inferior to that of their Pb-based counterparts, primarily due to higher open-circuit voltage (Voc) losses and lower fill factors (FFs). Herein, we report both perovskite top and bottom interfacial improvements by incorporating a facile fluorophenylethylammonium iodide (p-FPEAI)/ethyl acetate (EA) solution during the film crystal growth. Based on the analysis of perovskite crystallization, film growth, and strain relaxation, the mechanisms behind these interfacial improvements have been well understood. Furthermore, p-FPEAI could reduce the defect density and nonradiative recombination losses, thus attributing to the improved Voc and FF. Finally, the treated device achieved a PCE of 20.14% with a Voc of up to 0.84 V, which is among the highest reported values so far for Pb-Sn alloyed PSCs without additional precursor additives. In addition, the unencapsulated p-FPEAI-treated device maintained its initial efficiency of approximately 92% after being kept in a nitrogen atmosphere for 1 month, in contrast to the control device which retained only 30% of its initial value. Our findings provide a comprehension for understanding the effect of bulky cations as antisolvents on fabricating highly efficient Pb-Sn alloyed perovskite solar cells.

19.
Plants (Basel) ; 13(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38337925

RESUMO

Chlorophyll content reflects plants' photosynthetic capacity, growth stage, and nitrogen status and is, therefore, of significant importance in precision agriculture. This study aims to develop a spectral and color vegetation indices-based model to estimate the chlorophyll content in aquaponically grown lettuce. A completely open-source automated machine learning (AutoML) framework (EvalML) was employed to develop the prediction models. The performance of AutoML along with four other standard machine learning models (back-propagation neural network (BPNN), partial least squares regression (PLSR), random forest (RF), and support vector machine (SVM) was compared. The most sensitive spectral (SVIs) and color vegetation indices (CVIs) for chlorophyll content were extracted and evaluated as reliable estimators of chlorophyll content. Using an ASD FieldSpec 4 Hi-Res spectroradiometer and a portable red, green, and blue (RGB) camera, 3600 hyperspectral reflectance measurements and 800 RGB images were acquired from lettuce grown across a gradient of nutrient levels. Ground measurements of leaf chlorophyll were acquired using an SPAD-502 m calibrated via laboratory chemical analyses. The results revealed a strong relationship between chlorophyll content and SPAD-502 readings, with an R2 of 0.95 and a correlation coefficient (r) of 0.975. The developed AutoML models outperformed all traditional models, yielding the highest values of the coefficient of determination in prediction (Rp2) for all vegetation indices (VIs). The combination of SVIs and CVIs achieved the best prediction accuracy with the highest Rp2 values ranging from 0.89 to 0.98, respectively. This study demonstrated the feasibility of spectral and color vegetation indices as estimators of chlorophyll content. Furthermore, the developed AutoML models can be integrated into embedded devices to control nutrient cycles in aquaponics systems.

20.
Adv Mater ; : e2313656, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315898

RESUMO

Exciplex systems are promising candidates for thermally activated delayed fluorescence (TADF) molecules because of the small energy difference between the lowest singlet and triplet excited states (ΔEST ). However, realizing high-efficiency and low-external-quantum-efficiency (EQE) roll-off in solution-processed organic light-emitting diodes (OLEDs) using an exciplex system remains a formidable challenge. In this study, two (HLCT)-type isomers with a spiro skeleton, 2-t BuspoCz-TRZ and 10-t BuspoCz-TRZ, are designed and synthesized as acceptors of exciplexes, where tert-butylspirofluorene indole is regarded as a donor and the triazine unit as an acceptor. Green exciplex emissions are observed for the 2-t BuspoCz-TRZ:TAPC and 10-t BuspoCz-TRZ:TAPC exciplexes, indicating distinct TADF characteristics with a very small ΔEST of 35 ± 5 meV. By using the TADF exciplex system based on the HLCT acceptor as an emitter, solution-processable OLEDs achieve a maximum external quantum efficiency (EQEmax ) of 20.8%. Furthermore, a high EQEmax > 25% with a very low-efficiency roll-off (≈3.5% at 1000 cd m-2 ) is obtained for solution-processable phosphorescent devices using HLCT-based exciplexes as the host matrix of phosphors. This study paves the way for a novel strategy for designing acceptor exciplex molecules for effective TADF molecules and host matrices in solution-processable OLEDs.

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