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Mesenchymal stem cell-derived exosomes(MSCs-Exos) offer promising therapeutic potential for a wide range of tissues and organs such as bone/cartilage, nerves, skin, fat, and endocrine organs. In comparison to the application of mesenchymal stem cells (MSCs), MSCs-Exos address critical challenges related to rejection reactions and ethical concerns, positioning themselves as a promising cell-free therapy. As exosomes are extracellular vesicles, their effective delivery necessitates the use of carriers. Consequently, the selection of hydrogel materials as scaffolds for exosome delivery has become a focal point of contemporary research. The diversity of hydrogel scaffolds, which can take various forms such as injectable types, dressings, microneedles, and capsules, leads to differing choices among researchers for treating diseases within the same domain. This variability in hydrogel materials poses challenges for the translation of findings into clinical practice. The review highlights the potential of hydrogel-loaded exosomes in different fields and introduces the advantages and disadvantages of different forms of hydrogel applications. It aims to provide a multifunctional and highly recognized hydrogel scaffold option for tissue regeneration at specific sites, improve clinical translation efficiency, and benefit the majority of patients. [Display omitted] • Exosomes derived from mesenchymal stem cells represent an ideal cell-free therapeutic approach. • The strategy of loading exosomes into hydrogel materials has emerged as a prominent topic in the biomedical field. • The diverse mechanisms of action of hydrogel scaffolds influence their clinical translation efficiency. • This approach is anticipated to offer valuable insights for biomedical applications targeting various organs or tissues. [ABSTRACT FROM AUTHOR]

• A survival signature-based reliability approach for the multi-state system with both dependence and imprecision is developed. • The survival function is derived through a structural reliability treatment. • Two numerical algorithms are developed to address the efficient computation of the survival function. • A numerical case and a real application example are demonstrated for validation and to illustrate the benefits of our approach. Reliability evaluation of a multi-state system (MSS) with dependent components makes much practical sense because the independent identical assumption (i.i.d.) assumption between different components is sometimes impractical in the context of real engineering cases. The task becomes more challenging if imprecision gets involved due to the pervasive uncertainty. The loss of monotony resulting from the introduction of imprecise parameters makes many analytical reliability methods not applied. To address this challenge, in this paper, we develop a survival signature-based reliability framework for an MSS taking into account both dependence and uncertainty. In our framework, the survival function is derived through some unique structural reliability treatments. Vine copula and imprecise probability are integrated and embedded within the framework to address the case that dependence and imprecision simultaneously appear. Implementation-wise, two numerical simulation algorithms are developed to address some complicated cases in which the analytical solution is not available. For demonstration and validation, both the numerical case and application examples are presented. The results show the superiority of the proposed method and its potential in real engineering use. [ABSTRACT FROM AUTHOR]

As a result of increasingly stringent power supply requirements and diverse application scenarios, the development of hybrid nanogenerators that can combine multiple power generation modes has gradually become a hot research topic. In this work, the PR-HNG, a piezo/triboelectric hybrid nanogenerator based on a pitched roof structure, is proposed and is used efficiently to perform discrete mechanical energy harvesting. Using the flexible connection of its separated roof-like trigger mechanism, the PR-HNG operates through inertia under vibration conditions and achieves a satisfactory working state with very low mechanical loss. At 10 Hz, the instantaneous open-circuit voltage V OC and short-circuit current I SC of the PR-HNG can reach 800 V and 9.6 mA (1.60 A/m2), respectively, and no obvious attenuation occurs during high-intensity and long-term operation. After connection to a load via a rectifier bridge, the PR-HNG has a maximum power output of 575 μW/cm2 and can charge a 2 mF capacitor up to more than 2.5 V in only 30 s; these two performance parameters are better than the reported values for other similar types of HNG. In practical applications, this PR-HNG can easily drive more than 1440 commercial light-emitting diodes and can drive small electronic devices in real time. Therefore, the PR-HNG has been demonstrated to provide a credible and promising solution for fabrication of self-powered monitoring systems for use in industrial environments. [Display omitted] • A pitched roof-like HNG effectively inherits the performance of TENG and PENG. • The HNG also has credible output performance even at different inclinations. • The power density of HNG is up to 5.75 W/m2 and 145.3 W/m3. • The HNG has strong charging ability, which assists monitoring system in IIoT. [ABSTRACT FROM AUTHOR]

Objective Reproduction is an energetically expensive process. Insufficient calorie reserves, signaled to the brain through peripheral signals such as leptin, suppress fertility. Recently, fibroblast growth factor 21 (FGF21) was implicated as a signal from the liver to the hypothalamus that directly inhibits the hypothalamic–gonadotropin axis during fasting and starvation. However, FGF21 itself increases metabolic rate and can induce weight loss, which suggests that the effects of FGF21 on fertility may not be direct and may reflect changes in energy balance. Methods To address this important question, we evaluated fertility in several mouse models with elevated FGF21 levels including ketogenic diet fed mice, fasted mice, mice treated with exogenous FGF21 and transgenic mice over-expressing FGF21. Results We find that ketogenic diet fed mice remain fertile despite significant elevation in serum FGF21 levels. Absence of FGF21 does not alter transient infertility induced by fasting. Centrally infused FGF21 does not suppress fertility despite its efficacy in inducing browning of inguinal white adipose tissue. Furthermore, a high fat diet (HFD) can restore fertility of female FGF21-overexpressing mice, a model of growth restriction, even in the presence of supraphysiological serum FGF21 levels. Conclusions We conclude that FGF21 is not a direct physiological regulator of fertility in mice. The infertility observed in FGF21 overexpressing mice is likely driven by the increased energy expenditure and consequent excess calorie requirements resulting from high FGF21 levels. [ABSTRACT FROM AUTHOR]

Depressive disorder is a severe global public health problem. It is crucial to evaluate the global incidence trends of depressive disorder. The incidence data were drawn from the Global Burden of Disease Study (GBD) 2019. Estimates were presented by global and sociodemographic index (SDI) quintiles, and the age-period-cohort (APC) model was used to estimate the incidence trends. APC analysis indicated a decline in depressive disorder incidence globally (net drift = −0.24%, 95%CI: −0.29, −0.18), except for an increase in SDI regions (net drift = 0.07, 95%CI:0, 0.14). In high SDI regions, depressive disorder incidence increased among the younger and declined among the elder population, whereas the opposite trend was observed in middle and low-middle SDI regions. The depressive disorder incidence increased significantly among people aged 15 to 24 years after adjusting for age effects, decreased since 2000 after adjusting for period effects and increased rapidly in the birth cohort after 1990 in high SDI by adjusting for cohort effects. Globally, there was a declining trend of depressive disorder incidence in 1990–2019. Specifically, the incidence was declining globally in younger populations, while increasing in older populations. However, this trend differed depending on the SDI of the region. [ABSTRACT FROM AUTHOR]

The thermal conductivities of the 3D carbon nanotubes (CNTs), CNT/epoxy resin (CNT/EP) composites, graphene/EP composites and CNT/graphene/EP composites are systematically investigated via mesoscopic simulations using smoothed particle hydrodynamics (SPH) and dissipative particle dynamics (DPD). The effects of the CNT length and overall mass density on the thermal conductivity of the CNTs are discussed. Moreover, the influences of the loading and size of the fillers on the thermal conductivities of the CNT/EP, graphene/EP and CNTs/graphene/EP composites are investigated. The results have shown that introducing the CNT and graphene fillers simultaneously to the epoxy resin can improve the thermal conductivity of the composites most effectively. The study demonstrates that coupled DPD and SPH model is a viable approach to understand the thermal conductivities of nanocomposites at a reduced computational cost compared to full atomistic simulation. [ABSTRACT FROM AUTHOR]

Ceramics joining has been widely applied in MEMS sensors, microwave and imaging devices as well as other ceramic packaging applications to fabricate multifunctional ceramic components. In this study, a glass frit with gradient thermal expansion coefficient (TEC) has been applied as the bonding material to join the ceramic of Al 2 O 3 and AlN. This glass frit consists of two types of glasses with different TEC. The Al 2 O 3 and AlN ceramics have been successfully joined with this glass frit in muffle furnace at 850 °C for 1 h. The bonding strength of Al 2 O 3 /AlN ceramic joined via this glass frit exceeds 40 MPa without any cracks in the joining interface, which is much superior compared with that of conventional glass frit bonding. Our work demonstrates that the gradient-TEC glass frit bonding is an effective method to join different types of ceramics. [ABSTRACT FROM AUTHOR]