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1.
J Med Chem ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34644502

RESUMO

Icaritin is an active ingredient in Epimedium, which has a variety of pharmacological activities. However, the low activity of Icaritin and the unclear target greatly limit its application. Therefore, based on the structure of Icaritin, we adopted the strategy of replacing toxic groups and introducing active groups to design and synthesize a series of new analogues. The top compound C3 exhibited better antimultiple myeloma activity with an IC50 of 1.09 µM for RPMI 8226 cells, induced RPMI 8226 apoptosis, and blocked the cell cycle in the S phase. Importantly, transcriptome analysis, cellular thermal shift assay, and microscale thermophoresis assay confirmed that DEPTOR was the target of C3. Moreover, we explored its binding mode with C3. Especially, C3 displayed satisfactory inhibition of tumor growth in RPMI 8226 xenografts without obvious side effects. In summary, C3 was discovered as a novel putative inhibitor of DEPTOR for the treatment of multiple myeloma.

2.
J Bone Miner Res ; 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34633122

RESUMO

The possible mechanisms underlying the quantitative and qualitative effects of cinacalcet on bone were explored in a chronic kidney disease-mineral and bone disorder (CKD) mouse model in relation to the influence of the interactions among the OC endoplasmic reticulum (ER) stress, autophagy and apoptosis pathways on osteoclast (OC) differentiation. Body weight and biochemical parameters improved significantly in the CKD+cinacalcet groups compared to the CKD group. Micro-computerized tomography revealed both cortical and trabecular parameters deteriorated significantly in the CKD group and were reversed by cinacalcet in a dose-dependent manner. Nano-indentation analysis of bone quality proved that both cortical hardness and elastic modulus improved significantly with high dose cinacalcet treatment. In vitro studies revealed that cinacalcet inhibited RANKL/RANK-induced OC differentiation in a concentration-dependent manner through a close interaction between activation of caspase-related apoptosis, reversal of OC autophagy through the Akt/mTOR and AMPK pathways and attenuation of the OC ER stress/CREBH/NFATc1 signaling pathway. Cinacalcet improves both bone quantity and bone quality in CKD mouse model and inhibits OC differentiation through regulation of the interactions among the apoptosis, ER stress and autophagy pathways within OC. This article is protected by copyright. All rights reserved.

3.
Int J Mol Sci ; 22(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34681927

RESUMO

Uremic toxins, such as indoxyl sulfate (IS) and kynurenine, accumulate in the blood in the event of kidney failure and contribute to further bone damage. To maintain the homeostasis of the skeletal system, bone remodeling is a persistent process of bone formation and bone resorption that depends on a dynamic balance of osteoblasts and osteoclasts. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates the toxic effects of uremic toxins. IS is an endogenous AhR ligand and is metabolized from tryptophan. In osteoclastogenesis, IS affects the expression of the osteoclast precursor nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) through AhR signaling. It is possible to increase osteoclast differentiation with short-term and low-dose IS exposure and to decrease differentiation with long-term and/or high-dose IS exposure. Coincidentally, during osteoblastogenesis, through the AhR signaling pathway, IS inhibits the phosphorylation of ERK, and p38 reduces the expression of the transcription factor 2 (Runx2), disturbing osteoblastogenesis. The AhR antagonist resveratrol has a protective effect on the IS/AhR pathway. Therefore, it is necessary to understand the multifaceted role of AhR in CKD, as knowledge of these transcription signals could provide a safe and effective method to prevent and treat CKD mineral bone disease.

4.
J Phys Chem Lett ; : 10040-10051, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34623167

RESUMO

Inspired by experimentally discovering ferromagnetism and ferroelectricity in two-dimensional (2D) CrGeTe3 and CuInP2S6 with similar geometric structures, respectively, we systematically investigated ferroic properties in a large family of 2D MIMIIGe2X6 (MI and MII = metal elements, X = S/Se/Te) by combining high-throughput first-principles calculations and the machine learning method. We identified 12 stable 2D multiferroics containing simultaneously ferromagnetic (FM) and ferroelectric (FE) properties and 35 2D ferromagnets without FE polarization. Particularly, the predicted FM Curie temperatures (TC) of eight 2D FM+FE semiconductors are close to or above room temperature. The ferroelectricity originates from the spontaneous geometric symmetry breaking induced by the unexpected shift of Ge-Ge atomic pairs and the emergence of Ge lone pair electrons, which also strengthens the p-d orbital hybridization between X atoms and metal atoms, leading to enhanced super-super-exchange interactions and raising the FM TC. Our findings not only enrich the family of 2D ferroic materials and present room-temperature FM semiconductors but also disclose the mechanism of the emerging ferroelectricity and enhanced ferromagnetism, which sheds light on the realization of high temperature multiferroics as well as FM semiconductors.

5.
Adv Sci (Weinh) ; : e2102666, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34523247

RESUMO

Necrosis induces strong inflammation with undesirable implications in clinics compared with apoptosis. Fortunately, the switch between necrosis and apoptosis could be realized by tailoring the appropriate structural properties of gold nano rods (GNRs) that could precisely modulate cell death pathways. Herein, the intracellular interaction between GNRs and organelles is monitored and it is found that lysosomes dominates necrosis/apoptosis evoking. Then the surface molecule density of GNRs, which is first defined as ρsurf. molecule (Nsurf. molecules /(a × π × Diameter × Length)), mediates lysosome activities as the membrane permeabilization (LMP), the Cathepsin B and D release, the cross-talk between lysosome and different organelles, which selectively evokes apoptosis or necrosis and the production of TNF-α from macrophages. GNRs with small ρsurf. molecule mainly induce apoptosis, while with large ρsurf. molecule they greatly contribute to necrosis. Interestingly, necrosis can be suppressed by GNRs with higher ρsurf. molecule due to the overexpression of key protease caspase 8, which cleaves the RIP1-RIP3 complex and activates caspase 3 followed by necrosis to apoptosis transition. This investigation indicates that the ρsurf. molecule greatly affects the utility of nanomaterials and different structural properties of nanomaterials have different implications in clinics.

6.
J Am Chem Soc ; 143(38): 15606-15615, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34542273

RESUMO

Light-emitting diodes (LEDs) based on metal halide perovskite quantum dots (QDs) have achieved impressive external quantum efficiencies; however, the lack of surface protection of QDs, combined with efficiency droop, decreases device operating lifetime at brightnesses of interest. The epitaxial incorporation of QDs within a semiconducting shell provides surface passivation and exciton confinement. Achieving this goal in the case of perovskite QDs remains an unsolved challenge in view of the materials' chemical instability. Here, we report perovskite QDs that remain stable in a thin layer of precursor solution of perovskite, and we use strained QDs as nucleation centers to drive the homogeneous crystallization of a perovskite matrix. Type-I band alignment ensures that the QDs are charge acceptors and radiative emitters. The new materials show suppressed Auger bi-excition recombination and bright luminescence at high excitation (600 W cm-2), whereas control materials exhibit severe bleaching. Primary red LEDs based on the new materials show an external quantum efficiency of 18%, and these retain high performance to brightnesses exceeding 4700 cd m-2. The new materials enable LEDs having an operating half-life of 2400 h at an initial luminance of 100 cd m-2, representing a 100-fold enhancement relative to the best primary red perovskite LEDs.

7.
Nanoscale ; 13(35): 14694-14704, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533170

RESUMO

Beyond the conventional trial-and-error method, machine learning offers a great opportunity to accelerate the discovery of functional materials, but still often suffers from difficulties such as limited materials data and the unbalanced distribution of target properties. Here, we propose the ab initio Bayesian active learning method that combines active learning and high-throughput ab initio calculations to accelerate the prediction of desired functional materials with ultrahigh efficiency and accuracy. We apply it as an instance to a large family (3119) of two-dimensional hexagonal binary compounds with unbalanced materials properties, and accurately screen out the materials with maximal electric polarization and proper photovoltaic band gaps, respectively, whereas the computational costs are significantly reduced by only calculating a few tenths of the possible candidates in comparison with a random search. This approach shows the enormous advantages for the cases with unbalanced distribution of target properties. It can be readily applied to seek a broad range of advanced materials.

8.
Int J Mol Sci ; 22(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34445700

RESUMO

Severe acute respiratory syndrome coronavirus 2 is a new, highly pathogenic virus that has recently elicited a global pandemic called the 2019 coronavirus disease (COVID-19). COVID-19 is characterized by significant immune dysfunction, which is caused by strong but unregulated innate immunity with depressed adaptive immunity. Reduced and delayed responses to interferons (IFN-I/IFN-III) can increase the synthesis of proinflammatory cytokines and extensive immune cell infiltration into the airways, leading to pulmonary disease. The development of effective treatments for severe COVID-19 patients relies on our knowledge of the pathophysiological components of this imbalanced innate immune response. Strategies to address innate response factors will be essential. Significant efforts are currently underway to develop vaccines against SARS-CoV-2. COVID-19 vaccines, such as inactivated DNA, mRNA, and protein subunit vaccines, have already been applied in clinical use. Various vaccines display different levels of effectiveness, and it is important to continue to optimize and update their composition in order to increase their effectiveness. However, due to the continuous emergence of variant viruses, improving the immunity of the general public may also increase the effectiveness of the vaccines. Many observational studies have demonstrated that serum levels of vitamin D are inversely correlated with the incidence or severity of COVID-19. Extensive evidence has shown that vitamin D supplementation could be vital in mitigating the progression of COVID-19 to reduce its severity. Vitamin D defends against SARS-CoV-2 through a complex mechanism through interactions between the modulation of innate and adaptive immune reactions, ACE2 expression, and inhibition of the renin-angiotensin system (RAS). However, it remains unclear whether Vit-D also plays an important role in the effectiveness of different COVID-19 vaccines. Based on analysis of the molecular mechanism involved, we speculated that vit-D, via various immune signaling pathways, plays a complementary role in the development of vaccine efficacy.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Vitamina D/administração & dosagem , Vitamina D/sangue , Animais , COVID-19/sangue , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Ensaios Clínicos como Assunto , Humanos , Imunogenicidade da Vacina , Pandemias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2/isolamento & purificação , Vitamina D/imunologia
9.
Adv Mater ; 33(41): e2103394, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34425038

RESUMO

The open-circuit voltage (Voc ) of perovskite solar cells is limited by non-radiative recombination at perovskite/carrier transport layer (CTL) interfaces. 2D perovskite post-treatments offer a means to passivate the top interface; whereas, accessing and passivating the buried interface underneath the perovskite film requires new material synthesis strategies. It is posited that perovskite ink containing species that bind strongly to substrates can spontaneously form a passivating layer with the bottom CTL. The concept using organic spacer cations with rich NH2 groups is implemented, where readily available hydrogens have large binding affinity to under-coordinated oxygens on the metal oxide substrate surface, inducing preferential crystallization of a thin 2D layer at the buried interface. The passivation effect of this 2D layer is examined using steady-state and time-resolved photoluminescence spectroscopy: the 2D interlayer suppresses non-radiative recombination at the buried perovskite/CTL interface, leading to a 72% reduction in surface recombination velocity. This strategy enables a 65 mV increase in Voc for NiOx based p-i-n devices, and a 100 mV increase in Voc for SnO2 -based n-i-p devices. Inverted solar cells with 20.1% power conversion efficiency (PCE) for 1.70 eV and 22.9% PCE for 1.55 eV bandgap perovskites are demonstrated.

10.
Zhongguo Zhen Jiu ; 41(8): 887-91, 2021 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-34369700

RESUMO

To analyze the collaborative use and separation reasons of lifting-thrusting and twirling reinforcing and reducing manipulation. Lifting-thrusting manipulation and twirling manipulation are two important contents of acupuncture methods. In traditional acupuncture and moxibustion, the two methods were used in reinforcing and reducing concert, which was mainly related to the therapeutic thought guided by the qi-blood theory and the influence of the human body structure on the technique manipulation. After the Republic of China, the separation of lifting-thrusting manipulation and twirling manipulation gradually appeared. It was related to the widespread use of "scientific acupuncture method" in later generations and the integration of neuroscience into the acupuncture treatment system.


Assuntos
Terapia por Acupuntura , Moxibustão , Humanos , Remoção , Agulhas , Taiwan
11.
Biomacromolecules ; 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34378928

RESUMO

The cryopreservation (CP) of cell/tissue is indispensable in medical science. However, the formation of ice during cooling and ice recrystallization/growth in time of thawing present significant risk of cell/tissue damage upon analysis of CP process. Herein, the natural and biocompatible silk fibroin (SF) with regular hydrophobic and hydrophilic domains, were first employed as a cryoprotectant (CPA), to the CP of human bone-derived mesenchymal stem cells (hBMSCs), which has been routinely cyropreserved for cell-based therapies. Addtion of SF can regulate the formation of ice crystals during cooling process because of its strong hydration ability in the comparation to the cryopreservation medium (CM) without SF. Moreover, the devitrification-induced recrystallization/growth of ice during the thawing process is suppressed. Most importantly, the addition of 10 mg mL-1 SF can achieve 81.28% cell viability of cryopreserved hBMSCs as similar as those with the addition of 180 mg mL-1 Ficoll 70 (commercial CPA), and the functions of the cryopreserved hBMSCs are maintained as good as that of the fresh ones. This work is not only significant for meeting the ever-increasing demand of cell therapy, but also trailblazing for designing materials in controlling ice formation and growth during the CP of other cells and tissues.

12.
Vaccines (Basel) ; 9(8)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34452010

RESUMO

The SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic has posed a huge threat to global health because of its rapid spread and various mutant variants. Critical illness occurs in the elderly and vulnerable individuals, such as those with chronic kidney disease. The severity of SARS-CoV-2 infection is associated with the severity of chronic kidney disease (CKD)and even kidney transplantation (KT) because of the chronic use of immunosuppressive agents. To develop adaptive immunity against SARS-CoV-2, vaccination against the spike protein is important. Current phase III trials of vaccines against SARS-CoV-2 have not focused on a specific group of individuals, such as patients with CKD or those undergoing dialysis or kidney transplantation. Chronic use of immunosuppressive agents might disturb the immune response to the SARS-CoV-2 spike protein. On the basis of limited evidence, the immune compromised status of CKD patients might decrease neutralizing antibody development after a single dose of a specific vaccine. Boosting dosage more than the protocol might increase the titer of the neutralizing antibody in CKD patients. Further evidence is needed to understand the factors disturbing the immunogenicity of the SARS-CoV-2 vaccine, and CKD patients should receive the recommended dose of the SARS-CoV-2 vaccine due to their relatively immune compromised status.

13.
Rev Sci Instrum ; 92(7): 075004, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340432

RESUMO

Valveless piezoelectric pumps usually have less flow than valve piezoelectric pumps, but the valve piezoelectric pumps have some limitations, such as high cost, complex structure, and difficult installation. In order to solve the problem of the low flow rate of the valveless piezoelectric pump, a valveless piezoelectric pump with multi-stage fluid guiding bodies is proposed. Based on the structure and working principle of the piezoelectric pump, the forward energy loss equation is established, and analysis on parameters affecting the energy loss of the pump is then conducted. COMSOL Multiphysics is adopted to construct a two-dimensional model of velocity and von Mises stress distribution. The valveless piezoelectric pumps were then fabricated based on 3D printing technologies, and the prototypes were tested. The results show that the output performance of the pump is the best when the working voltage is 220 V, the frequency is 95 Hz, the length of the oblique arm of the fluid guiding body is 3.5 mm, the spacing is 9.05 mm, and the thickness is 0.1 mm. The maximum flow rate is 520.6 ml/min. In addition, the experimental results prove that the asymmetric fluid guiding body placed in the center of the pump chamber can improve the performance of piezoelectric pumps. This study extends the application of piezoelectric valveless pumps in micromechanical cooling.

14.
Adv Sci (Weinh) ; : e2101125, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449133

RESUMO

Perovskite quantum dots (QDs) are of interest for solution-processed lasers; however, their short Auger lifetime has limited lasing operation principally to the femtosecond temporal regime the photoexcitation levels to achieve optical gain threshold are up to two orders of magnitude higher in the nanosecond regime than in the femtosecond. Here the authors report QD superlattices in which the gain medium facilitates excitonic delocalization to decrease Auger recombination and in which the macroscopic dimensions of the structures provide the optical feedback required for lasing. The authors develope a self-assembly strategy that relies on sodiumd-an assembly director that passivates the surface of the QDs and induces self-assembly to form ordered three-dimensional cubic structures. A density functional theory model that accounts for the attraction forces between QDs allows to explain self-assembly and superlattice formation. Compared to conventional organic-ligand-passivated QDs, sodium enables higher attractive forces, ultimately leading to the formation of micron-length scale structures and the optical faceting required for feedback. Simultaneously, the decreased inter-dot distance enabled by the new ligand enhances exciton delocalization among QDs, as demonstrated by the dynamically red-shifted photoluminescence. These structures function as the lasing cavity and the gain medium, enabling nanosecond-sustained lasing with a threshold of 25 µJ cm-2 .

15.
Nurse Educ Pract ; 55: 103128, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34315062

RESUMO

AIM: The aim of this study was to design a multidisciplinary teaching method that combines game-based learning with a clinical situation-based teaching program and to test learning motivation, learning satisfaction and self-confidence. BACKGROUND: Research has suggested that game-based learning and clinical situation-based teaching can effectively capture student attention and stimulate student learning motivation as well as increase learning satisfaction and self-confidence. DESIGN: The randomized and experimental design used in this study was a pretest-posttest control group design. METHODS: This study recruited participants from a technical college in the north of Taiwan. The experimental group (receiving multidisciplinary teaching) comprised 48 participants and the control group (receiving traditional teaching) comprised 50 participants. Participants took a pretest before the multidisciplinary teaching intervention, received a total of 12 weeks of intervention and then took a posttest within 1 week of the end of the course. These participants completed a questionnaire regarding learning satisfaction, confidence and learning performance. RESULTS: The multidisciplinary teaching intervention improved learning satisfaction (t = 7.36, p < 0.001), self-confidence (t = 7.34, p < 0.001) and learning performance (t = 6.66, p < 0.001). Multidisciplinary teaching interventions can improve learning satisfaction, self-confidence and learning performance among nursing students. CONCLUSIONS: Multidisciplinary teaching should be promoted in the context of nursing teaching and students have the multidisciplinary learning.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Avaliação Educacional , Humanos , Aprendizagem , Satisfação Pessoal , Ensino
16.
Bioconjug Chem ; 32(8): 1915-1925, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34247477

RESUMO

A three-dimensional (3D) printed biodegradable hydrogel scaffold with a strong self-expanding ability to conform to the contour of irregular bone defects and be closely adjacent to host tissues is reported herein. The scaffold has a triple cross-linked network structure consisting of photo-cross-linked polyacrylamide (PAAM) and polyurethane (PU) as the primary IPN network and chemical cross-linked gelatin (Gel) as the secondary network, which confers the scaffold with good mechanical properties. The addition of PU in the polymerization process of acrylamide (AAM) can improve the ultraviolet (UV) photocuring efficiency of the hydrogel and incorporate abundant hydrogen bonds between the PAAM copolymer chain and the PU chain. The results show that the hydrogel scaffold contains regular structures with smooth morphology, excellent dimensional stability, and uniform aperture. The degradation rate of the hydrogel scaffold is controllable through adjusting cross-linking agents and can be up to about 60% after degradation for 28 days. More importantly, the rapid self-inflating characteristic of the scaffold in water, that is, the volume of hydrogel scaffold can increase to about 8 times that of their own in an hour and can generate a slight compressive stress on the surrounding host tissue, thus stimulating the reconstruction and growth of new bone tissues. The in vitro experiment indicates that the scaffold is nontoxic and biocompatible. The in vivo experiment shows that the PU/PAAM/Gel chemically cross-linked scaffold displays the desirable osteogenic capability. This UV-curable 3D printed self-adaptive and degradable hydrogel scaffold holds great potential for nonload-bearing bone repair.

17.
Diabetes ; 70(10): 2250-2263, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34315726

RESUMO

Choline metabolite trimethylamine N-oxide (TMAO) has been recognized as a risk factor of gestational diabetes mellitus (GDM), but its exact role in GDM has not been reported. In this study, we focused on the placenta development to reveal the role of TMAO in GDM. We found that the TMAO levels in peripheral and cord plasma were increased in women with GDM and that TMAO levels were positively correlated with newborn weight and placental thickness. Neutrophil extracellular traps (NETs) in the peripheral and cord plasma and the myeloperoxidase expression in the placenta of women with GDM also increased. NETs could inhibit the proliferation, migration, invasion, and angiogenesis of HTR-8/Svneo cells. However, TMAO not only could inhibit the formation of NETs but also could enhance the biological function of HTR-8/Svneo cells. With induction of GDM in NETs-deficient PAD4-/- and wild-type mice, the placental weight of PAD4-/- mice increased significantly. TMAO feeding also inhibited the formation of NETs and further increased the weight of the placenta and fetuses, and this increase did not affect the placental structure. Our data indicate that higher TMAO levels and the formation of abnormal NETs were associated with GDM. TMAO not only could promote the development of the placenta and fetuses but also could inhibit the formation of NETs.

18.
Front Pharmacol ; 12: 683156, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305596

RESUMO

The clinical controversy of rosiglitazone as a hypoglycemic agent is potentially associated with heart failure, mainly due to its potent activation of peroxisome proliferator-activated receptor γ (PPARγ). PPARγ partial agonists showed superior pharmacological profiles to rosiglitazone. This study compared differences in cardiac morphology and function of the PPARγ partial agonist CMHX008 with rosiglitazone. High-fat diet (HFD) induced obese mice, ob/ob mice and cardiomyocytes overexpressing PPARγ2 were treated with CMHX008 or rosiglitazone. Heart function, myocardial morphology, and hypertrophy-related gene expression were examined. Clinical information from patients with type 2 diabetes mellitus (T2DM) who had taken rosiglitazone and undergone Doppler echocardiography was collected. HFD and ob/ob mice significantly developed cardiac contractile dysfunction, with upregulated PPARγ2 protein levels in heart tissues. Cardiomyocytes of HFD and ob/ob mice were disorderly arranged, the cell areas expanded, and collagen accumulated. In vitro cardiomyocytes overexpressing PPARγ2 displayed obvious structural abnormalities and high mRNA levels of ANP and BNP, critical cardiac hypertrophy-related genes. HFD-fed mice treated with rosiglitazone or CMHX008 had significantly improved cardiac function, but rosiglitazone induced higher expression of ANP and ßMHC and hypertrophic cardiomyopathy, while CMHX008 did not. Patients with T2DM taking rosiglitazone exhibited increased thickness of the posterior wall and the ventricular septum, suggesting cardiac hypertrophy. Our findings show that diabetic cardiomyopathy was associated with ectopic overexpression of PPARγ2. The full agonist rosiglitazone prevents cardiac dysfunction at the expense of compensatory hypertrophy, while the partial agonist CMHX008 shared a comparable protective effect without altering the structure of cardiomyocytes.

19.
ACS Appl Mater Interfaces ; 13(29): 34954-34961, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34270889

RESUMO

Three-dimensional (3D) printing is becoming a revolutionary technique across various fields. Especially, digital light processing (DLP) 3D printing shows advantages of high resolution and high efficiency. However, multifunctional monomers are commonly used to meet the rapid liquid-to-solid transformation during DLP printing, and the extensive production of unreprocessable thermosets will lead to resource waste and environmental problems. Here, we report a family of dynamic polymers with highly tailorable mechanical properties for DLP printing. The dynamic polymers cross-linked by ionic bonding and hydrogen bonding endow printed objects with excellent self-healing and recycling ability. The mechanical properties of printed objects can be easily tailored from soft elastomers to rigid plastics to satisfy practical applications. Taking advantage of the dynamic cross-linking, various assembling categories, including 2D to 3D, small to large 3D structures, and same to different materials assembly, and functional devices with a self-healing capacity can be realized. This study not only helps to address environmental issues caused by traditional DLP-printed thermosets but also realizes the on-demand fabrication of complex structures.

20.
J Am Chem Soc ; 143(29): 10970-10976, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34196528

RESUMO

Contemporary thin-film photovoltaic (PV) materials contain elements that are scarce (CIGS) or regulated (CdTe and lead-based perovskites), a fact that may limit the widespread impact of these emerging PV technologies. Tin halide perovskites utilize materials less stringently regulated than the lead (Pb) employed in mainstream perovskite solar cells; however, even today's best tin-halide perovskite thin films suffer from limited carrier diffusion length and poor film morphology. We devised a synthetic route to enable in situ reaction between metallic Sn and I2 in dimethyl sulfoxide (DMSO), a reaction that generates a highly coordinated SnI2·(DMSO)x adduct that is well-dispersed in the precursor solution. The adduct directs out-of-plane crystal orientation and achieves a more homogeneous structure in polycrystalline perovskite thin films. This approach improves the electron diffusion length of tin-halide perovskite to 290 ± 20 nm compared to 210 ± 20 nm in reference films. We fabricate tin-halide perovskite solar cells with a power conversion efficiency of 14.6% as certified in an independent lab. This represents a ∼20% increase compared to the previous best-performing certified tin-halide perovskite solar cells. The cells outperform prior earth-abundant and heavy-metal-free inorganic-active-layer-based thin-film solar cells such as those based on amorphous silicon, Cu2ZnSn(S/Se)4 , and Sb2(S/Se)3.

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