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4.
Natl Sci Rev ; 11(10): nwae329, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39439720

RESUMEN

Thermoelectric Peltier coolers (PCs) are being increasingly used as temperature stabilizers for optoelectronic devices. Increasing integration drives PC miniaturization, requiring thermoelectric materials with good strength. We demonstrate a simultaneous gain of thermoelectric and mechanical performance in (Bi, Sb)2Te3, and successfully fabricate micro PCs (2 × 2 mm2 cross-section) that show excellent maximum cooling temperature difference of 89.3 K with a hot-side temperature of 348 K. A multi-step process involving annealing, hot-forging and composition design, is developed to modify the atomic defects and nano- and microstructures. The peak ZT is improved to ∼1.50 at 348 K, and the flexural and compressive strengths are significantly enhanced to ∼140 MPa and ∼224 MPa, respectively. These achievements hold great potential for advancing solid-state refrigeration technology in small spaces.

5.
Angew Chem Int Ed Engl ; : e202415896, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39450503

RESUMEN

Hybrid lead halides show significant potential in photocatalysis due to their excellent photophysical properties, but the atomically precise modification of their organic component to achieve synergistic interactions with the lead halide units remains a great challenge. Herein, for the first time, we have employed the crystal engineering strategy to construct a class of single-atom-substituted hybrid lead halides with electron donor-acceptor (D-A) effect. The lead halide frameworks consist of 1D linear [PbCl]+ chains as inorganic building units and benzoxadiazole/benzothiadiazole/ benzoselenadiazole-funtionalized dicarboxylates as linkers. The covalent bonding between the organic ligands with electron-withdrawing groups and the electron-rich lead halide units not only facilitate the charge separation, but also enhance structural robustness that is critical for photocatalysis. The D-A structured lead halides serve as highly efficient heterogeneous photooxidation catalysts, including aerobic oxidation of C(sp3)-H bonds, oxidative coupling of primary amines, oxidation of phenylboronic acids and selective oxidation of sulfides that are demonstrated in 30 examples. Importantly, these photooxidation reactions are able to be driven by natural sunlight and ambient air to afford quantitative yields. Moreover, our lead halide photocatalysts are successful to fix into a photocatalytic flow system, which enables the flow-type synthesis of high value-added photooxidation products on a gram scale.

6.
Plants (Basel) ; 13(20)2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39458788

RESUMEN

Enhancing the genetic transformation efficiency of major crops remains a significant challenge, primarily due to their suboptimal regeneration efficiency. Developmental regulators, known as key regulatory genes, involved in plant meristem and somatic embryo formation, play a crucial role in improving plant meristem induction and regeneration. This review provides a detailed summary of the molecular mechanisms and regulatory networks of many developmental regulators, in the context of enhancing the genetic transformation efficiency in major crops. We also propose strategies for exploring and utilizing additional developmental regulators. Further investigation into the mechanisms of these regulators will deepen our understanding of the regenerative capacity and genetic transformation processes of plants, offering valuable support for future crop improvement efforts. The discovery of novel developmental regulators is expected to further advance crop transformation and the effective manipulation of various developmental regulators could provide a promising approach in order to enhance genetic transformation efficiency.

10.
Nat Commun ; 15(1): 5915, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39003277

RESUMEN

GeTe is a promising p-type material with increasingly enhanced thermoelectric properties reported in recent years, demonstrating its superiority for mid-temperature applications. In this work, the thermoelectric performance of GeTe is improved by a facile composite approach. We find that incorporating a small amount of boron particles into the Bi-doped GeTe leads to significant enhancement in power factor and simultaneous reduction in thermal conductivity, through which the synergistic modulation of electrical and thermal transport properties is realized. The thermal mismatch between the boron particles and the matrix induces high-density dislocations that effectively scatter the mid-frequency phonons, accounting for a minimum lattice thermal conductivity of 0.43 Wm-1K-1 at 613 K. Furthermore, the presence of boron/GeTe interfaces modifies the interfacial potential barriers, resulting in increased Seebeck coefficient and hence enhanced power factor (25.4 µWcm-1K-2 at 300 K). Consequently, we obtain a maximum figure of merit Zmax of 4.0 × 10-3 K-1 at 613 K in the GeTe-based composites, which is the record-high value in GeTe-based thermoelectric materials and also superior to most of thermoelectric systems for mid-temperature applications. This work provides an effective way to further enhance the performance of GeTe-based thermoelectrics.

11.
Int J Cardiol ; 413: 132345, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38996817

RESUMEN

BACKGROUND: Door-to-balloon time (DTBT) for ST-elevation myocardial infarction (STEMI) is a performance metric by which primary percutaneous coronary intervention (PPCI) services are assessed. METHODS: Consecutive patients presenting with STEMI undergoing PPCI between January 2007 to December 2019 from the Singapore Myocardial Infarction Registry were included. Patients were stratified based on DTBT (≤60 min, 61-90 min, 91-180 min) and Killip status (I-III vs. IV). Outcomes assessed included all-cause mortality and major adverse cardiovascular events (MACE) at 30-days and 1-year. RESULTS: In total, 13,823 patients were included, with 82.59% achieving DTBT ≤90 min and 49.77% achieving DTBT ≤60 min. For Killip I-III (n = 11,591,83.85%), the median DTBT was 60[46-78]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 1.08%, 2.17% and 4.33% respectively (p < 0.001). On multivariate analysis, however, there was no significant difference for 30-day and 1-year outcomes across all DTBT (p > 0.05). For Killip IV, the median DTBT was 68[51-91]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 11.74%, 20.48% and 35.06% respectively (p < 0.001). On multivariate analysis for 30-day and 1-year outcomes, DTBT 91-180 min was an independent predictor of worse outcomes (p < 0.05), but there was no significant difference between DTBT of ≤60 min and 61-90 min (p > 0.05). CONCLUSION: In Killip I-III patients, DTBT had no significant impact on outcomes upon adjustment for confounders. Conversely, for Killip IV patients, a DTBT of >90 min was associated with significantly higher adverse outcomes, with no differences between a DTBT of ≤60 min vs. 61-90 min. Outcomes in STEMI involve a complex interplay of factors and recommendations of a lowered DTBT of ≤60 min will require further evaluation.


Asunto(s)
Intervención Coronaria Percutánea , Sistema de Registros , Infarto del Miocardio con Elevación del ST , Tiempo de Tratamiento , Humanos , Masculino , Femenino , Infarto del Miocardio con Elevación del ST/cirugía , Infarto del Miocardio con Elevación del ST/terapia , Infarto del Miocardio con Elevación del ST/mortalidad , Persona de Mediana Edad , Tiempo de Tratamiento/normas , Anciano , Intervención Coronaria Percutánea/métodos , Singapur/epidemiología , Factores de Tiempo , Resultado del Tratamiento , Estudios Retrospectivos
12.
J Am Chem Soc ; 146(25): 17355-17364, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38870542

RESUMEN

GeSe, an analogue of SnSe, shows promise in exhibiting exceptional thermoelectric performance in the Pnma phase. The constraints on its dopability, however, pose challenges in attaining optimal carrier concentrations and improving ZT values. This study demonstrates a crystal structure evolution strategy for achieving highly doped samples and promising ZTs in GeSe via LiBiTe2 alloying. A rhombohedral phase (R3m) can be stabilized in the GeSe-LiBiTe2 system, further evolving into a cubic (Fm3̅m) phase with a rising temperature. The band structures of GeSe-LiBiTe2 in the rhombohedral and cubic phases feature a similar multiple-valley energy-converged valence band of L and Σ bands. The observed high carrier concentration (∼1020 cm-3) reflects the effective convergence of these bands, enabling a high density-of-states effective mass and an enhanced power factor. Moreover, a very low lattice thermal conductivity of 0.6-0.5 W m-1 K-1 from 300 to 723 K is achieved in 0.9GeSe-0.1LiBiTe2, approaching the amorphous limit value. This remarkably low lattice thermal conductivity is related to phonon scattering from point defects, planar vacancies, and ferroelectric instability-induced low-energy Einstein oscillators. Finally, a maximum ZT value of 1.1 to 1.3 at 723 K is obtained, with a high average ZT value of over 0.8 (400-723 K) in 0.9GeSe-0.1LiBiTe2 samples. This study establishes a viable route for tailoring crystal structures to significantly improve the performance of GeSe-related compounds.

13.
Adv Mater ; 36(30): e2403651, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38692649

RESUMEN

Photocatalytic CO2 reduction to high-value-added C2+ products presents significant challenges, which is attributed to the slow kinetics of multi-e- CO2 photoreduction and the high thermodynamic barrier for C-C coupling. Incorporating redox-active Co2+/Ni2+ cations into lead halide photocatalysts has high potentials to improve carrier transport and introduce charge polarized bimetallic sites, addressing the kinetic and thermodynamic issues, respectively. In this study, a coordination-driven synthetic strategy is developed to introduce 3d transition metals into the interlamellar region of layered organolead iodides with atomic precision. The resultant bimetallic halide hybrids exhibit selective photoreduction of CO2 to C2H5OH using H2O vapor at the evolution rates of 24.9-31.4 µmol g-1 h-1 and high selectivity of 89.5-93.6%, while pristine layered lead iodide yields only C1 products. Band structure calculations and photoluminescence studies indicate that the interlayer Co2+/Ni2+ species greatly contribute to the frontier orbitals and enhance exciton dissociation into free carriers, facilitating carrier transport between adjacent lead iodide layers. In addition, Bader charge distribution calculations and in situ experimental spectroscopic studies reveal that the asymmetric Ni-O-Pb bimetallic catalytic sites exhibit intrinsic charge polarization, promoting C-C coupling and leading to the formation of the key *OC-CHO intermediate.

14.
Exp Eye Res ; 244: 109948, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38815790

RESUMEN

Severe corneal injury can lead to blindness even after prompt treatment. 14-3-3zeta, a member of an adaptor protein family, contributes to tissue repair by enhancing cellular viability and inhibiting fibrosis and inflammation in renal disease or arthritis. However, its role in corneal regeneration is less studied. In this study, filter disc of 2-mm diameter soaked in sodium hydroxide with a concentration of 0.5 N was placed at the center of the cornea for 30 s to establish a mouse model of corneal alkali injury. We found that 14-3-3zeta, which is mainly expressed in the epithelial layer, was upregulated following injury. Overexpression of 14-3-3zeta in ocular tissues via adeno-associated virus-mediated subconjunctival delivery promoted corneal wound healing, showing improved corneal structure and transparency. In vitro studies on human corneal epithelial cells showed that 14-3-3zeta was critical for cell proliferation and migration. mRNA-sequencing in conjunction with KEGG analysis and validation experiments revealed that 14-3-3zeta regulated the mRNA levels of ITGB1, PIK3R1, FGF5, PRKAA1 and the phosphorylation level of Akt, suggesting the involvement of the PI3K-Akt pathway in 14-3-3zeta-mediated tissue repair. 14-3-3zeta is a potential novel therapeutic candidate for treating severe corneal injury.


Asunto(s)
Proteínas 14-3-3 , Quemaduras Químicas , Lesiones de la Cornea , Cicatrización de Heridas , Animales , Humanos , Masculino , Ratones , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/biosíntesis , Western Blotting , Quemaduras Químicas/metabolismo , Quemaduras Químicas/patología , Quemaduras Químicas/tratamiento farmacológico , Movimiento Celular , Proliferación Celular , Células Cultivadas , Lesiones de la Cornea/metabolismo , Lesiones de la Cornea/patología , Lesiones de la Cornea/genética , Modelos Animales de Enfermedad , Epitelio Corneal/metabolismo , Epitelio Corneal/efectos de los fármacos , Epitelio Corneal/lesiones , Quemaduras Oculares/inducido químicamente , Regulación de la Expresión Génica , Homeostasis , Ratones Endogámicos C57BL , Hidróxido de Sodio , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología
15.
BMC Oral Health ; 24(1): 629, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807098

RESUMEN

BACKGROUND: In orthodontics, anterior open bite is a common malocclusion that recurs frequently. Because the causes of anterior open bite are so varied, medical professionals must create customized treatment programs for each patient based on their unique etiology. Through the lowering of the posterior teeth, closure of the anterior teeth gap, and cooperation with intermaxillary traction, the treatment plan outlined in this case study sought to achieve a stable occlusion. CASE PRESENTATION: This case report aims to describe an orthodontic camouflage treatment of a 15-year-old female patient with anterior open bite, arch width discrepancy and a history of temporomandibular joint disorder. The patient was treated with intermaxillary vertical elastics and the multiple edgewise arch wire (MEAW) approach. A satisfactory occlusion with a neutral molar relationship was attained after 29 months of orthodontic therapy. The condylography recording showed that this patient's occlusion tended to be more stable both before and after our treatment. The purpose of this case study is to provide an overview of an orthodontic camouflage treatment for a female patient, who had a history of temporomandibular joint disease, anterior open bite, and arch width disparity. CONCLUSIONS: Our results demonstrated that more attention should be paid to levelling the occlusal plane, intrusion of the molars, decompression of temporomandibular joints and the etiology factors of malocclusion during the orthodontic period for those patients with anterior open bite.


Asunto(s)
Mordida Abierta , Trastornos de la Articulación Temporomandibular , Humanos , Femenino , Adolescente , Mordida Abierta/terapia , Trastornos de la Articulación Temporomandibular/terapia , Ortodoncia Correctiva/métodos , Cefalometría , Planificación de Atención al Paciente
16.
J Ovarian Res ; 17(1): 116, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807145

RESUMEN

BACKGROUND: PCOS patients with unexpectedly low oocyte yield following conventional ovarian stimulation are referred to as suboptimal responders. However, identifying suboptimal responders presents a significant challenge within reproductive medicine and limited research exists on the occurrence of suboptimal response. This analysis aimed to develop a predictive model of suboptimal response during in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatments in PCOS patients. METHODS: This retrospective study involved a cohort of 313 PCOS patients undergoing their first IVF/ICSI cycle from 2019 to 2022. Univariate logistic regression analyses, least absolute shrinkage, selection operator regression analysis, and recursive feature elimination were employed to identify relevant characteristics and construct predictive models. Moreover, a nomogram was constructed based on the best model. Receiver operating characteristic curves, decision curve analysis (DCA), and calibration curves were used to evaluate the model. RESULTS: The predictors included in the model were age, Anti-Mullerian hormone, antral follicle count, and basal follicle-stimulating hormone. The area under the receiver operating characteristic curve (AUC) was 0.7702 (95% confidence interval 0.7157-0.8191). The AUC, along with the DCA curve and calibration curve, demonstrated a satisfactory level of congruence and discrimination ability. CONCLUSION: The nomogram effectively predicted the probability of suboptimal response in PCOS patients undergoing gonadotropin-releasing hormone antagonist protocol during IVF/ICSI treatment.


Asunto(s)
Fertilización In Vitro , Hormona Liberadora de Gonadotropina , Inducción de la Ovulación , Síndrome del Ovario Poliquístico , Inyecciones de Esperma Intracitoplasmáticas , Adulto , Femenino , Humanos , Embarazo , Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Nomogramas , Inducción de la Ovulación/métodos , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Estudios Retrospectivos , Curva ROC
17.
Blood Adv ; 8(12): 3200-3213, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38621200

RESUMEN

ABSTRACT: A comprehensive international consensus on the cytogenetic risk-group stratification of KMT2A-rearranged (KMT2A-r) pediatric acute myeloid leukemia (AML) is lacking. This retrospective (2005-2016) International Berlin-Frankfurt-Münster Study Group study on 1256 children with KMT2A-r AML aims to validate the prognostic value of established recurring KMT2A fusions and additional cytogenetic aberrations (ACAs) and to define additional, recurring KMT2A fusions and ACAs, evaluating their prognostic relevance. Compared with our previous study, 3 additional, recurring KMT2A-r groups were defined: Xq24/KMT2A::SEPT6, 1p32/KMT2A::EPS15, and 17q12/t(11;17)(q23;q12). Across 13 KMT2A-r groups, 5-year event-free survival probabilities varied significantly (21.8%-76.2%; P < .01). ACAs occurred in 46.8% of 1200 patients with complete karyotypes, correlating with inferior overall survival (56.8% vs 67.9%; P < .01). Multivariable analyses confirmed independent associations of 4q21/KMT2A::AFF1, 6q27/KMT2A::AFDN, 10p12/KMT2A::MLLT10, 10p11.2/KMT2A::ABI1, and 19p13.3/KMT2A::MLLT1 with adverse outcomes, but not those of 1q21/KMT2A::MLLT11 and trisomy 19 with favorable and adverse outcomes, respectively. Newly identified ACAs with independent adverse prognoses were monosomy 10, trisomies 1, 6, 16, and X, add(12p), and del(9q). Among patients with 9p22/KMT2A::MLLT3, the independent association of French-American-British-type M5 with favorable outcomes was confirmed, and those of trisomy 6 and measurable residual disease at end of induction with adverse outcomes were identified. We provide evidence to incorporate 5 adverse-risk KMT2A fusions into the cytogenetic risk-group stratification of KMT2A-r pediatric AML, to revise the favorable-risk classification of 1q21/KMT2A::MLLT11 to intermediate risk, and to refine the risk-stratification of 9p22/KMT2A::MLLT3 AML. Future studies should validate the associations between the newly identified ACAs and outcomes and unravel the underlying biological pathogenesis of KMT2A fusions and ACAs.


Asunto(s)
N-Metiltransferasa de Histona-Lisina , Leucemia Mieloide Aguda , Proteína de la Leucemia Mieloide-Linfoide , Humanos , Proteína de la Leucemia Mieloide-Linfoide/genética , Niño , N-Metiltransferasa de Histona-Lisina/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Femenino , Preescolar , Adolescente , Lactante , Pronóstico , Aberraciones Cromosómicas , Reordenamiento Génico , Estudios Retrospectivos
18.
Adv Sci (Weinh) ; 11(23): e2400870, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38553790

RESUMEN

Thermoelectric materials are highly promising for waste heat harvesting. Although thermoelectric materials research has expanded over the years, bismuth telluride-based alloys are still the best for near-room-temperature applications. In this work, a ≈38% enhancement of the average ZT (300-473 K) to 1.21 is achieved by mixing Bi0.4Sb1.6Te3 with an emerging thermoelectric material Sb2Si2Te6, which is significantly higher than that of most BiySb2-yTe3-based composites. This enhancement is facilitated by the unique interface region between the Bi0.4Sb1.6Te3 matrix and Sb2Si2Te6-based precipitates with an orderly atomic arrangement, which promotes the transport of charge carriers with minimal scattering, overcoming a common factor that is limiting ZT enhancement in such composites. At the same time, high-density dislocations in the same region can effectively scatter the phonons, decoupling the electron-phonon transport. This results in a ≈56% enhancement of the thermoelectric quality factor at 373 K, from 0.41 for the pristine sample to 0.64 for the composite sample. A single-leg device is fabricated with a high efficiency of 5.4% at ΔT = 164 K further demonstrating the efficacy of the Sb2Si2Te6 compositing strategy and the importance of the precipitate-matrix interface microstructure in improving the performance of materials for relatively low-temperature applications.

19.
Nat Mater ; 23(4): 527-534, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38454027

RESUMEN

The liquid-like feature of thermoelectric superionic conductors is a double-edged sword: the long-range migration of ions hinders the phonon transport, but their directional segregation greatly impairs the service stability. We report the synergetic enhancement in figure of merit (ZT) and stability in Cu1.99Se-based superionic conductors enabled by ion confinement effects. Guided by density functional theory and nudged elastic band simulations, we elevated the activation energy to restrict ion migrations through a cation-anion co-doping strategy. We reduced the carrier concentration without sacrificing the low thermal conductivity, obtaining a ZT of ∼3.0 at 1,050 K. Notably, the fabricated device module maintained a high conversion efficiency of up to ∼13.4% for a temperature difference of 518 K without obvious degradation after 120 cycles. Our work could be generalized to develop electrically and thermally robust functional materials with ionic migration characteristics.

20.
Front Endocrinol (Lausanne) ; 15: 1340329, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505752

RESUMEN

Background: Identifying poor ovarian response (POR) among patients with good ovarian reserve poses a significant challenge within reproductive medicine. Currently, there is a lack of published data on the potential risk factors that could predict the occurrence of unexpected POR. The objective of this study was to develop a predictive model to assess the individual probability of unexpected POR during in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatments. Methods: The development of the nomogram involved a cohort of 10,404 patients with normal ovarian reserve [age, ≤40 years; antral follicle count (AFC), ≥5; and anti-Müllerian hormone (AMH), ≥1.2 ng/ml] from January 2019 to December 2022. Univariate regression analyses and least absolute shrinkage and selection operator regression analysis were employed to ascertain the characteristics associated with POR. Subsequently, the selected variables were utilized to construct the nomogram. Results: The predictors included in our model were body mass index, basal follicle-stimulating hormone, AMH, AFC, homeostasis model assessment of insulin resistance (HOMA-IR), protocol, and initial dose of gonadotropin. The area under the receiver operating characteristic curve (AUC) was 0.753 [95% confidence interval (CI) = 0.7257-0.7735]. The AUC, along with the Hosmer-Lemeshow test (p = 0.167), demonstrated a satisfactory level of congruence and discrimination ability of the developed model. Conclusion: The nomogram can anticipate the probability of unexpected POR in IVF/ICSI treatment, thereby assisting professionals in making appropriate clinical judgments and in helping patients to effectively manage expectations.


Asunto(s)
Inducción de la Ovulación , Inyecciones de Esperma Intracitoplasmáticas , Femenino , Humanos , Masculino , Adulto , Inyecciones de Esperma Intracitoplasmáticas/métodos , Inducción de la Ovulación/métodos , Semen , Fertilización In Vitro/métodos , Ovario
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