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1.
iScience ; 27(5): 109689, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38706840

RESUMEN

The distinct folding accompanied by its polymorphic character renders DNA G-quadruplexes promising biomolecular building blocks to construct novel DNA-based and supramolecular assemblies. However, the highly polar nature of DNA limits the use of G-quadruplexes to water as a solvent. In addition, the archetypical G-quadruplex fold needs to be stabilized by metal-cations, which is usually a potassium ion. Here, we show that a noncovalent PEGylation process enabled by electrostatic interactions allows the first metal-free G-quadruplexes in organic solvents. Strikingly, incorporation of an iron-containing porphyrin renders the self-assembled metal-free G-quadruplex catalytically active in organic solvents. Hence, these "supraG4zymes" enable DNA-based catalysis in organic media. The results will allow the broad utilization of DNA G-quadruplexes in nonaqueous environments.

2.
Cancer ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38644692

RESUMEN

BACKGROUND: Long-term daily use of aspirin reduces incidence and mortality due to colorectal cancer (CRC). This study aimed to analyze the effect of aspirin on the tumor microenvironment, systemic immunity, and on the healthy mucosa surrounding cancer. METHODS: Patients with a diagnosis of CRC operated on from 2015 to 2019 were retrospectively analyzed (METACCRE cohort). Expression of mRNA of immune surveillance-related genes (PD-L1, CD80, CD86, HLA I, and HLA II) in CRC primary cells treated with aspirin were extracted from Gene Expression Omnibus-deposited public database (GSE76583). The experiment was replicated in cell lines. The mucosal immune microenvironment of a subgroup of patients participating in the IMMUNOREACT1 (ClinicalTrials.gov NCT04915326) project was analyzed with immunohistochemistry and flow cytometry. RESULTS: In the METACCRE Cohort, 12% of 238 patients analyzed were aspirin users. Nodal metastasis was significantly less frequent (p = .008) and tumor-infiltrating lymphocyte infiltration was higher (p = .02) among aspirin users. In the CRC primary cells and selected cell lines, CD80 mRNA expression was increased following aspirin treatment (p = .001). In the healthy mucosa surrounding rectal cancer, the ratio of CD8/CD3 and epithelial cells expressing CD80 was higher in aspirin users (p = .027 and p = .034, respectively). CONCLUSIONS: These data suggested that regular aspirin use may have an active role in enhancing immunosurveillance against CRC.

3.
J Colloid Interface Sci ; 665: 286-298, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38531274

RESUMEN

Tailoring porous host materials, as an effective strategy for storing sulfur and restraining the shuttling of soluble polysulfides in electrolyte, is crucial in the design of high-performance lithium-sulfur (Li-S) batteries. However, for the widely studied conductive hosts such as mesoporous carbon, how the aspect ratio affects the confining ability to polysulfides, ion diffusion as well as the performances of Li-S batteries has been rarely studied. Herein, ordered mesoporous carbon (OMC) is chosen as a proof-of-concept prototype of sulfur host, and its aspect ratio is tuned from over âˆ¼ 2 down to below âˆ¼ 1.2 by using ordered mesoporous silica hard templates with variable length/width scales. The correlation between the aspect ratio of OMCs and the electrochemical performances of the corresponding sulfur-carbon cathodes are systematically studied with combined electrochemical measurements and microscopic characterizations. Moreover, the evolution of sulfur species in OMCs at different discharge states is scrutinized by small-angle X-ray scattering. This study gives insight into the aspect ratio effects of mesoporous host on battery performances of sulfur cathodes, providing guidelines for designing porous host materials for high-energy sulfur cathodes.

4.
Adv Mater ; 36(19): e2311526, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38327037

RESUMEN

The phase-transfer ligand exchange of PbS quantum dots (QDs) has substantially simplified device fabrication giving hope for future industrial exploitation. However, this technique when applied to QDs of large size (>4 nm) gives rise to inks with poor colloidal stability, thus hindering the development of QDs photodetectors in short-wavelength infrared range. Here, it is demonstrated that methylammonium lead iodide ligands can provide sufficient passivation of PbS QDs of size up to 6.7 nm, enabling inks with a minimum of ten-week shelf-life time, as proven by optical absorption and solution-small angle X-ray scattering. Furthermore, the maximum linear electron mobility of 4.7 × 10-2 cm2 V-1 s-1 is measured in field-effect transistors fabricated with fresh inks, while transistors fabricated with the same solution after ten-week storage retain 74% of the average starting electron mobility, demonstrating the outstanding quality both of the fresh and aged inks. Finally, photodetectors fabricated via blade-coating exhibit 76% external quantum efficiency at 1300 nm and 1.8 × 1012 Jones specific detectivity, values comparable with devices fabricated using ink with lower stability and wasteful methods such as spin-coating.

5.
Sci Adv ; 10(2): eadi3606, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38198554

RESUMEN

While nature extensively uses electrostatic bonding between oppositely charged polymers to assemble and stabilize materials, harnessing these interactions in synthetic systems has been challenging. Synthetic materials cross-linked with a high density of ionic bonds, such as polyelectrolyte complexes, only function properly when their charge interactions are attenuated in the presence of ample amounts of water; dehydrating these materials creates such strong Coulombic bonding that they become brittle, non-thermoplastic, and virtually impossible to process. We present a strategy to intrinsically moderate the electrostatic bond strengths in apolar polymeric solids by the covalent grafting of attenuator spacers to the charge carrying moieties. This produces a class of polyelectrolyte materials that have a charge density of 100%, are processable and malleable without requiring water, are highly solvent- and water-resistant, and are fully recyclable. These materials, which we coin "compleximers," marry the properties of thermoplastics and thermosets using tailored ionic bonding alone.

6.
Small ; 20(7): e2306219, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37803926

RESUMEN

Nanocontainers that can sense and respond to environmental stimuli like cells are desirable for next-generation delivery systems. However, it is still a grand challenge for synthetic nanocontainers to mimic or even surpass the shape adaption of cells, which may produce novel compartments for cargo loading. Here, this work reports the engineering of compartment network with a single polymer vesicle by unraveling osmotic stress-dependent deformation. Specifically, by manipulating the way in exerting the stress, sudden increase or gradual increase, polymer vesicles can either undergo deflation into the stomatocyte, a bowl-shaped vesicle enclosing a new compartment, or tubulation into the tubule of varied length. Such stress-dependent deformation inspired us to program the shape transformation of polymer vesicles, including tubulation, deflation, or first tubulation and then deflation. The coupled deformation successfully transforms the polymer vesicle into the stomatocyte with tubular arms and a network of two or three small stomatocytes connected by tubules. To the author's knowledge, these morphologies are still not accessed by synthetic nanocontainers. This work envisions that the network of stomatocytes may enable the loading of different catalysts to construct novel motile systems, and the well-defined morphology of vesicles helps to define the effect of morphology on cellar uptake.

7.
Small Methods ; 8(2): e2300040, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37287443

RESUMEN

Two terminal passive devices are regarded as one of the promising candidates to solve the processor-memory bottleneck in the Von Neumann computing architectures. Many different materials are used to fabricate memory devices, which have the potential to act as synapses in future neuromorphic electronics. Metal halide perovskites are attractive for memory devices as they display high density of defects with a low migration barrier. However, to become promising for a future neuromorphic technology, attention should be paid on non-toxic materials and scalable deposition processes. Herein, it is reported for the first time the successful fabrication of resistive memory devices using quasi-2D tin-lead perovskite of composition (BA)2 MA4 (Pb0.5 Sn0.5 )5 I16 by blade coating. The devices show typical memory characteristics with excellent endurance (2000 cycles), retention (105  s), and storage stability (3 months). Importantly, the memory devices successfully emulate synaptic behaviors such as spike-timing-dependent plasticity, paired-pulse facilitation, short-term potentiation, and long-term potentiation. A mix of slow (ionic) transport and fast (electronic) transport (charge trapping and de-trapping) is proven to be responsible for the observed resistive switching behavior.

8.
Macromolecules ; 56(15): 5891-5904, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37576476

RESUMEN

Complex coacervates make up a class of versatile materials formed as a result of the electrostatic associations between oppositely charged polyelectrolytes. It is well-known that the viscoelastic properties of these materials can be easily altered with the ionic strength of the medium, resulting in a range of materials from free-flowing liquids to gel-like solids. However, in addition to electrostatics, several other noncovalent interactions could influence the formation of the coacervate phase depending on the chemical nature of the polymers involved. Here, the importance of intermolecular hydrogen bonds on the phase behavior, microstructure, and viscoelasticity of hyaluronic acid (HA)-chitosan (CHI) complex coacervates is revealed. The density of intermolecular hydrogen bonds between CHI units increases with increasing pH of coacervation, which results in dynamically arrested regions within the complex coacervate, leading to elastic gel-like behavior. This pH-dependent behavior may be very relevant for the controlled solidification of complex coacervates and thus for polyelectrolyte material design.

9.
Langenbecks Arch Surg ; 408(1): 263, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37402015

RESUMEN

BACKGROUND AND AIM: Prognostic Nutritional Index (PNI) is a useful tool to predict short-term results in patients undergoing surgery for gastrointestinal cancer. Few studies have addressed this issue in colorectal cancer or specifically in rectal cancer. We evaluated the prognostic relevance of preoperative PNI on morbidity of patients undergoing laparoscopic curative resection for rectal cancer (LCRRC). METHODS: PNI data and clinico-pathological characteristics of LCRRC patients (June 2005-December 2020) were evaluated. Patients with metastatic disease were excluded. Postoperative complications were evaluated using the Clavien-Dindo classification. RESULTS: A total of 182 patients were included in the analysis. Median preoperative PNI was 36.5 (IQR 32.8-41.2). Lower PNI was associated with females (p=0.02), older patients (p=0.0002), comorbidity status (p<0.0001), and those who did not receive neoadjuvant treatment (p=0.01). Post-operative complications occurred in 53 patients (29.1%), by the Clavien-Dindo classification: 40 grades I-II and 13 grades III-V. Median preoperative PNI was 35.0 (31.8-40.0) in complicated patients and 37.0 (33.0-41.5) in uncomplicated patients (p=0.09). PNI showed poor discriminative performance regarding postoperative morbidity (AUC 0.57) and was not associated with postoperative morbidity (OR 0.97) at multivariable analysis. CONCLUSIONS: Preoperative PNI was not associated with postoperative morbidity after LCRRC. Further research should focus on different nutritional indicators or hematological/immunological biomarkers.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Femenino , Humanos , Evaluación Nutricional , Pronóstico , Estudios Retrospectivos , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología , Complicaciones Posoperatorias/etiología , Laparoscopía/efectos adversos , Estado Nutricional
10.
ACS Macro Lett ; 12(8): 1071-1078, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37462370

RESUMEN

Despite the ever more versatile polymerization techniques that are becoming available, the synthesis of macromolecules with tailored functionalities can remain a lengthy endeavor. This becomes more conspicuous when the implementation of incompatible chemistries (i.e., strong polyelectrolytes) within sequence-controlled polymers is desired, often requiring (i) polymerization, (ii) chain extension, and (iii) postpolymerization modification. Herein, we explore the production of strong anionic/charge-neutral block copolymers (BCPs) in a one-pot fashion. This straightforward three-step process includes the synthesis of a macroinitiator and chain extension via rapid and efficient photomediated atom transfer radical polymerization, followed by in situ deprotection to expose the polyanionic domains. The resulting BCPs, which are strong amphiphiles by nature, are capable of self-assembly in aqueous media, as evidenced by dynamic light scattering, small-angle X-ray scattering, ζ-potential measurements, and transmission electron microscopy. We further demonstrate the versatility of our methodology by producing several BCPs through sampling of a single reaction mixture, enabling the straightforward production of strong polymer amphiphiles.

11.
Int J Colorectal Dis ; 38(1): 190, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37428283

RESUMEN

BACKGROUND: Technological development has offered laparoscopic colorectal surgeons new video systems to improve depth perception and perform difficult task in limited space. The aim of this study was to assess the cognitive burden and motion sickness for surgeons during 3D, 2D-4 K or 3D-4 K laparoscopic colorectal procedures and to report post-operative data with the different video systems employed. METHODS: Patients were assigned to either 3D, 2D-4 K or 3D-4 K video and two questionnaires (Simulator Sickness Questionnaire-SSQ- and NASA Task Load Index -TLX) were used during elective laparoscopic colorectal resections (October 2020-August 2022) from two operating surgeons. Short-term results of the operations performed with the three different video systems were also analyzed. RESULTS: A total of 113 consecutive patients were included: 41 (36%) in the 3D Group (A), 46 (41%) in the 3D-4 K Group and 26 (23%) in the 2D-4 K Group (C). Weighted and adjusted regression models showed no significant difference in cognitive load amongst the surgeons in the three groups of video systems when using the NASA-TLX. An increased risk for slight/moderate general discomfort and eyestrain in the 3D-4 K group compared with 2D-4 K group (OR = 3.5; p = 0.0057 and OR = 2.8; p = 0.0096, respectively) was observed. Further, slight/moderate difficulty focusing was lower in both 3D and 3D-4 K groups compared with 2D-4 K group (OR = 0.4; p = 0.0124 and OR = 0.5; p = 0.0341, respectively), and higher in the 3D-4 K group compared with 3D group (OR = 2.6; p = 0.0124). Patient population characteristics, operative time, post-operative staging, complication rate and length of stay were similar in the three groups of patients. CONCLUSIONS: 3D and 3D-4 K systems, when compared with 2D-4 K video technology, have a higher risk for slight/moderate general discomfort and eyestrain, but show lower difficulty focusing. Short post-operative outcomes do not differ, whichever imaging system is used.


Asunto(s)
Cognición , Neoplasias Colorrectales , Cirugía Colorrectal , Laparoscopía , Mareo por Movimiento , Humanos , Neoplasias Colorrectales/cirugía , Imagenología Tridimensional , Laparoscopía/efectos adversos , Laparoscopía/métodos , Tempo Operativo , Puntaje de Propensión , Encuestas y Cuestionarios
12.
Br J Surg ; 110(11): 1490-1501, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37478362

RESUMEN

BACKGROUND: Colon cancer in young patients is often associated with hereditary syndromes; however, in early-onset rectal cancer, mutations of these genes are rarely observed. The aim of this study was to analyse the features of the local immune microenvironment and the mutational pattern in early-onset rectal cancer. METHODS: Commonly mutated genes were analysed within a rectal cancer series from the University Hospital of Padova. Mutation frequency and immune gene expression in a cohort from The Cancer Genome Atlas ('TCGA') were compared and immune-cell infiltration levels in the healthy rectal mucosa adjacent to rectal cancers were evaluated in the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 ('IMMUNOREACT') series. RESULTS: In the authors' series, the mutation frequency of BRAF, KRAS, and NRAS, as well as microsatellite instability frequency, were not different between early- and late-onset rectal cancer. In The Cancer Genome Atlas series, among the genes with the most considerable difference in mutation frequency between young and older patients, seven genes are involved in the immune response and CD69, CD3, and CD8ß expression was lower in early-onset rectal cancer. In the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 series, young patients had a lower rate of CD4+ T cells, but higher T regulator infiltration in the rectal mucosa. CONCLUSION: Early-onset rectal cancer is rarely associated with common hereditary syndromes. The tumour microenvironment is characterized by a high frequency of mutations impairing the local immune surveillance mechanisms and low expression of immune editing-related genes. A constitutively low number of CD4 T cells associated with a high number of T regulators indicates an imbalance in the immune surveillance mechanisms.

13.
Adv Mater ; 35(33): e2302896, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37306654

RESUMEN

Metal halide perovskites show the capability of performing structural transformation, allowing the formation of functional heterostructures. Unfortunately, the elusive mechanism governing these transformations limits their technological application. Herein, the mechanism of 2D-3D structural transformation is unraveled as catalyzed by solvents. By combining a spatial-temporal cation interdiffusivity simulation with experimental findings, it is validated that, protic solvents foster the dissociation degree of formadinium iodide (FAI) via dynamic hydrogen bond, then the stronger hydrogen bond of phenylethylamine (PEA) cation with selected solvents compared to dissociated FA cation facilitates 2D-3D transformation from (PEA)2 PbI4 to FAPbI3 . It is discovered that, the energy barrier of PEA out-diffusion and the lateral transition barrier of inorganic slab are diminished. For 2D films the protic solvents catalyze grain centers (GCs) and grain boundaries (GBs) transforme into 3D phases and quasi-2D phases, respectively. While in the solvent-free case, GCs transform into 3D-2D heterostructures along the direction perpendicular to the substrate, and most GBs evolve into 3D phases. Finally, memristor devices fabricated using the transformed films uncover that, GBs composed of 3D phases are more prone to ion migration. This work elucidates the fundamental mechanism of structural transformation in metal halide perovskites, allowing their use to fabricate complex heterostructures.

14.
Proc Natl Acad Sci U S A ; 120(27): e2301279120, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37364098

RESUMEN

The design of stimuli-responsive systems in nanomedicine arises from the challenges associated with the unsolved needs of current molecular drug delivery. Here, we present a delivery system with high spatiotemporal control and tunable release profiles. The design is based on the combination of an hydrophobic synthetic molecular rotary motor and a PDMS-b-PMOXA diblock copolymer to create a responsive self-assembled system. The successful incorporation and selective activation by low-power visible light (λ = 430 nm, 6.9 mW) allowed to trigger the delivery of a fluorescent dye with high efficiencies (up to 75%). Moreover, we proved the ability to turn on and off the responsive behavior on demand over sequential cycles. Low concentrations of photoresponsive units (down to 1 mol% of molecular motor) are shown to effectively promote release. Our system was also tested under relevant physiological conditions using a lung cancer cell line and the encapsulation of an Food and Drug Administration (FDA)-approved drug. Similar levels of cell viability are observed compared to the free given drug showing the potential of our platform to deliver functional drugs on request with high efficiency. This work provides an important step for the application of synthetic molecular machines in the next generation of smart delivery systems.


Asunto(s)
Sistemas de Liberación de Medicamentos , Polímeros , Polímeros/química , Colorantes Fluorescentes , Línea Celular , Interacciones Hidrofóbicas e Hidrofílicas , Portadores de Fármacos/química
15.
J Laparoendosc Adv Surg Tech A ; 33(6): 570-578, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37130330

RESUMEN

Background: Sarcopenia is a useful tool in predicting short-term results in patients undergoing surgery for gastrointestinal cancer. However, there are few studies addressing this issue in colorectal cancer, and even less specifically focused on rectal cancer. We evaluated the prognostic relevance of preoperative skeletal mass index on postoperative morbidity in patients undergoing laparoscopic curative resection for rectal cancer. Methods: Skeletal mass index data and clinicopathological characteristics of rectal cancer patients in a 15-year period (June 2005-December 2020) were evaluated; patients with metastatic disease at surgery were excluded; postoperative complications within 30 days were evaluated using the Clavien-Dindo classification. Results: A total of 166 patients were included in the study. The overall prevalence of sarcopenia was 60%. BMI, Hb, or albumin were not associated with sarcopenia. Hospital stay was not correlated with sarcopenia. Postoperative complications occurred in 51 patients (31%); by the Clavien-Dindo classification 31 (61%) grade I, 10 (14.5%) grade II, and 10 (14.5%) grade III. Overall complications were not significantly different in sarcopenic and nonsarcopenic patients (P = .10). Considering only patients with complications, sarcopenia was found to be a predictor of more severe postoperative morbidity (odds ratio 12.7, P = .021). On multivariable analysis, sarcopenia was not associated with postoperative morbidity. Conclusions: Skeletal muscle status in rectal cancer patients undergoing curative resection was not associated with overall postoperative morbidity, although there was a correlation between sarcopenia and more severe complications. Further studies in a larger cohort of patients are needed before conclusions can be drawn on the relationship between muscular depletion and surgical outcomes in rectal cancer patients.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Sarcopenia , Humanos , Neoplasias del Recto/patología , Músculo Esquelético , Sarcopenia/complicaciones , Sarcopenia/epidemiología , Complicaciones Posoperatorias/etiología , Laparoscopía/efectos adversos , Prevalencia , Estudios Retrospectivos , Factores de Riesgo
16.
Int J Surg ; 109(3): 323-332, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37093072

RESUMEN

BACKGROUND: Studies evaluating sex differences in colorectal cancer (CRC) tumor microenvironment are limited, and no previous study has focused on rectal cancer patients' constitutive immune surveillance mechanisms. The authors aimed to assess gender-related differences in the immune microenvironment of rectal cancer patients. METHODS: A systematic review and meta-analysis were conducted up to 31 May 2021, including studies focusing on gender-related differences in the CRC tumor microenvironment. Data on the mutational profile of rectal cancer were extracted from the Cancer Genome Atlas (TCGA). A subanalysis of the two IMMUNOREACT trials (NCT04915326 and NCT04917263) was performed, aiming to detect gender-related differences in the immune microenvironment of the healthy mucosa in patients with early (IMMUNOREACT 1 cohort) and locally advanced rectal cancer following neoadjuvant therapy (IMMUNOREACT 2 cohort). In the retrospective IMMUNOREACT 1 cohort (therapy naive), the authors enrolled 442 patients (177 female and 265 male), while in the retrospective IMMUNOREACT 2 cohort (patients who had neoadjuvant therapy), we enrolled 264 patients (80 female and 184 male). In the prospective IMMUNOREACT 1 cohort (therapy naive), the authors enrolled 72 patients (26 female and 46 male), while in the prospective IMMUNOREACT 2 cohort (patients who had neoadjuvant therapy), the authors enrolled 105 patients (42 female and 63 male). RESULTS: Seven studies reported PD-L1 expression in the CRC microenvironment, but no significant difference could be identified between the sexes. In the TGCA series, mutations of SYNE1 and RYR2 were significantly more frequent in male patients with rectal cancer. In the IMMUNOREACT 1 cohort, male patients had a higher expression of epithelial cells expressing HLA class I, while female patients had a higher number of activated CD4+Th1 cells. Female patients in the IMMUNOREACT 2 cohort showed a higher infiltration of epithelial cells expressing CD86 and activated cytotoxic T cells (P=0.01). CONCLUSIONS: Male patients have more frequent oncogene mutations associated with a lower expression of T-cell activation genes. In the healthy mucosa of female patients, more Th1 cells and cytotoxic T cells suggest a potentially better immune response to the tumor. Sex should be considered when defining the treatment strategy for rectal cancer patients or designing prognostic scores.


Asunto(s)
Neoplasias del Recto , Humanos , Masculino , Femenino , Estudios de Cohortes , Estudios Retrospectivos , Estudios Prospectivos , Neoplasias del Recto/patología , Terapia Neoadyuvante , Microambiente Tumoral/genética
17.
Adv Mater ; : e2301404, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36999655

RESUMEN

Transport layers are of outmost importance for thin-film solar cells, determining not only their efficiency but also their stability. To bring one of these thin-film technologies toward mass production, many factors besides efficiency and stability become important, including the ease of deposition in a scalable manner and the cost of the different material's layers. Herein, highly efficient organic solar cells (OSCs), in the inverted structure (n-i-p), are demonstrated by using as electron transport layer (ETL) tin oxide (SnO2 ) deposited by atomic layer deposition (ALD). ALD is an industrial grade technique which can be applied at the wafer level and also in a roll-to-roll configuration. A champion power conversion efficiency (PCE) of 17.26% and a record fill factor (FF) of 79% are shown by PM6:L8-BO OSCs when using ALD-SnO2 as ETL. These devices outperform solar cells with SnO2 nanoparticles casted from solution (PCE 16.03%, FF 74%) and also those utilizing the more common sol-gel ZnO (PCE 16.84%, FF 77%). The outstanding results are attributed to a reduced charge carrier recombination at the interface between the ALD-SnO2 film and the active layer. Furthermore, a higher stability under illumination is demonstrated for the devices with ALD-SnO2 in comparison with those utilizing ZnO.

18.
Nanoscale ; 15(14): 6673-6685, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36929178

RESUMEN

Here we demonstrate blue LEDs with a peak wavelength of 481 nm, with outstanding colour purity of up to 88% (CIE coordinates (0.1092, 0.1738)), an external quantum yield of 5.2% and a luminance of 8260 cd m-2. These devices are based on quasi-2D PEA2(Cs0.75MA0.25)Pb2Br7, which is cast from solutions containing isopropylammonium (iPAm). iPAm as additive assist in supressing the formation of bulk-like phases, as pointed out by both photophysical and structural characterization. Additionally, the study of the excitation dynamics demonstrates a hindering of the energy transfer to domains of lower energy that generally undermines the performance and emission characteristics of blue-emitting LEDs based on quasi-2D perovskites. The achieved narrow distribution of quantum well sizes and the hindered energy transfer result in a thin film photoluminescence quantum yield exceeding 60%. Our work demonstrates the great potential to tailor the composition and the structure of thin films based on Ruddlesden-Popper phases to boost performance of optoelectronic devices - specifically blue perovskite LEDs.

19.
Int J Colorectal Dis ; 38(1): 34, 2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36773133

RESUMEN

BACKGROUND: Standard laparoscopic colorectal surgery relies on 2D image systems in most centers. However, 3D vision has gained popularity and is used nowadays in a constantly rising number of units. Right hemicolectomy with intracorporeal anastomosis and lymph node dissection represents a surgical procedure that may benefit the most from 3D vision. The aim of the study was to summarize the available literature on the use of 2D vs. 3D video imaging in patients undergoing laparoscopic right hemicolectomy. METHODS: A comprehensive literature review was conducted including Medline/PubMed, Embase, and Scopus (PROSPERO registration number CRD 42022344764) through October 2022. The systematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The risk of bias was evaluated using the ROBINS-I tool. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) guidelines and GRADEpro to develop a summary of evidence tables. Random-effects meta-analyses were conducted. RESULTS: Five observational retrospective studies (496 patients, 275 2D and 216 3D) were included. One study was rated as having a critical risk of bias; the remaining had low to moderate risk. 2D laparoscopic right hemicolectomy patients showed longer anastomotic time in 3/3 studies (MD = 3.32; 95%CI, 1.58-5.05; p = 0.002) and an upward trend in operative time in 4/5 studies (MD = 9.98; 95%CI, -1.42, 21.37; p = 0.086) compared to 3D. The two image video systems had similar short-term outcomes, including the number of lymph nodes harvested (MD = -0.67; 95%CI, -2.47, 1.13; p = 0.47), morbidity (OR post-operative complications = 1.12; 95%CI, 0.71-1.77; p = 0.62), and length of stay (MD = 0.27; 95%CI, -0.59, 1.13; p = 0.9). CONCLUSIONS: 2D and 2D laparoscopic right hemicolectomy had similar complications rate, with a shorter anastomotic time along with a downward trend in overall operative time for 3D. Larger prospective randomized trials are awaited before definitive conclusions can be drawn.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Colectomía/efectos adversos , Colectomía/métodos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Anastomosis Quirúrgica/métodos , Resultado del Tratamiento , Neoplasias del Colon/cirugía
20.
ACS Sustain Chem Eng ; 11(5): 1985-1994, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36778523

RESUMEN

Keratin is an important byproduct of the animal industry, but almost all of it ends up in landfills due to a lack of efficient recycling methods. To make better use of keratin-based natural resources, the current extraction and processing strategies need to be improved or replaced by more sustainable and cost-effective processes. Here, we developed a simple and environmentally benign method to process extracted keratin, using HCl to induce the formation of a coacervate, a separate aqueous phase with a very high protein concentration. Remarkably, this pH-induced coacervation did not result in the denaturation of keratin, and we could even observe an increase in the amount of ordered secondary structures. The low-pH coacervates could be extruded and wet-spun into high-performance keratin fibers, without requiring heating or any organic solvents. The secondary structure of keratin was largely conserved in these regenerated fibers, which exhibited excellent mechanical performance. The process developed in this study represents a simple and environmentally friendly strategy to upcycle waste keratin into high-performance materials.

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