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Clarifying the relationship between stress sensitivities of permeability and porosity is of great significance in guiding underground resource mining. More and more studies focus on how to construct stress sensitivity models to describe the relationship and obtain a comprehensive stress sensitivity of porous rock. However, the limitations of elastic deformation calculation and incompleteness of considered tortuosity sensitivity lead to the fact that the existing stress sensitivity models are still unsatisfactory in terms of accuracy and generalization. Therefore, a more accurate and generic stress sensitivity model considering elastic-structural deformation of capillary cross-section and tortuosity sensitivity is proposed in this paper. The elastic deformation is derived from the fractal scaling model and Hooke's law. Considering the effects of elastic-structural deformation on tortuosity sensitivity, an empirical formula is proposed, and the conditions for its applicability are clarified. The predictive performance of the proposed model for the permeability-porosity relationships is validated in several sets of publicly available experimental data. These experimental data are from different rocks under different pressure cycles. The mean and standard deviation of relative errors of predicted stress sensitivity with respect to experimental data are 2.63% and 1.91%. Compared with other models, the proposed model has higher accuracy and better predictive generalization performance. It is also found that the porosity sensitivity exponent α, which can describe permeability-porosity relationships, is 2 when only elastic deformation is considered. α decreases from 2 when structural deformation is also considered. In addition, α may be greater than 3 due to the increase in tortuosity sensitivity when tortuosity sensitivity is considered even if the rock is not fractured.

Recent discoveries demonstrated the skeleton’s role as an endocrine organ regulating whole-body glucose homeostasis. Glucose metabolism is critical for rapid cell proliferation and tumour growth through increasing glucose uptake and fermentation of glucose to lactate despite being in an aerobic environment. This hypothesis paper discusses emerging evidence on how bones can regulate whole-body glucose homeostasis with potential to impact on tumour growth and proliferation. Moreover, it proposes a clinical link between bone glucose metabolism and prognosis of cancer based on recent clinical trial data. Targeting metabolic pathways related with classic glucose metabolism and also bone metabolism, novel methods of cancer therapy and treatment could be developed. This paper objective is to highlight the need for future research on this altered metabolism with potential to change future management of cancer patients.

Abstract Currently, one in three adults worldwide may be obese or overweight. Obesity is characterized by an excess of energy‐storing white fat. An ingenious and sought‐after strategy against obesity is to activate energy‐consuming beige fat, which is converted from white fat or brown fat. However, existing tools for assessing brown or beige fat activation in vivo have certain limitations, such as being cumbersome and expensive. Optical imaging is a relatively straightforward and economical imaging technique that utilizes light to peer into the structural–functional information of living organisms at multiple scales. Despite the availability of various optical imaging modalities for detecting brown or beige fat, there is a dearth of literature summarizing relevant studies. Accordingly, this review focuses on these optical modalities and elaborates on their imaging principles, characteristics, and recent research advances in the detection of brown or beige fat. Their imaging targets, advantages, and disadvantages are further concluded. As a methodological reference, this review can guide the selection of optimal optical modalities to noninvasively profile brown or beige fat activation from a specific biological perspective, maximizing the potential of optical imaging in anti‐obesity assessment.

The ultrasonic liquid phase exfoliation method has emerged as an essential research direction for graphene preparation due to its cost-effectiveness and ability to minimize defects. However, this method faces challenges related to processing throughput when scaled up for industrial production. In this study, industrial grade ultrasonic homogenizers with different frequencies and probe types were evaluated for the preparation of FLG. In each experiment, 1.5 kg of graphite slurry was treated using a cyclic ultrasonic system. The results demonstrated that the 25 kHz dumbbell probe produced the thinnest FLG with the lowest defect density. Moreover, applying a static pressure of 0.2 MPa in the cycle system enhanced the cavitation-induced exfoliation of graphite sheets, effectively reducing the layer count and distribution range of FLG. This method improves the conductivity while minimizing defect density.

DICER1 syndrome is a rare tumour predisposition syndrome, associated with a range of benign and malignant tumours, which may occur during childhood. A high index of suspicion is required to ensure appropriate diagnosis and testing, with early treatment and surveillance of at-risk individuals. In this report, we present 5 patients with variants in DICER1 identified following diagnosis of a minimally invasive thyroid follicular cell carcinoma, a pineoblastoma, a pleuropulmonary blastoma, a urethral rhabdomyosarcoma and on sibling testing. Each of these children have presented at a young age, and 2 have presented with characteristic tumours prior to the ages currently recommended for initiation of routine screening. We discuss their presentation, management and follow up, as well as a review of the current literature on each associated tumour in relation to our patients. Overall, we demonstrate that DICER1 is a heterogenous condition and that there is a need for cascade testing of family members as well as regular screening for tumour development in affected children, although consideration should be made regarding initiating this screening at an earlier age depending on clinical findings.

The damage imaging method based on Lamb wave beamforming has been widely used in the field of SHM. The DAS method has a high imaging efficiency, but its ability to suppress interference signals is weak, resulting in low imaging resolution and signal-to-noise ratio. Drawing inspiration from the adaptive weighted MVDR damage imaging method, this paper constructs a neural network based on FCNN, with the images generated by the MVDR method as the target. By training the model, the mapping relationship between delayed channel input data and adaptive weighting factors is established, thereby improving the resolution and signal-to-noise ratio of Lamb wave damage imaging and achieving rapid imaging of damage. To verify the effectiveness and imaging performance of the FCNN method, imaging of two types of damage in aluminum plates is conducted through simulation and experiments, and the imaging results are compared and analyzed with DAS and MVDR. The results show that the imaging quality and the quantitative indicators of the FCNN method have not yet reached the performance level of the MVDR, but compared with DAS, FCNN has a significantly narrower main lobe width and lower sidelobe level. Furthermore, its quantitative indicators such as API, SNR, and FWHM are better than DAS. The proposed adaptive Lamb wave beamforming method based on FCNN combines high resolution and signal-to-noise ratio, as well as the advantage of rapid imaging, providing reference and support for real-time SHM based on Lamb waves.

Ultrasonic guided wave non-destructive testing technology, as one of the most widely used techniques in non-destructive testing, has encountered challenges in breaking the diffraction limit to achieve finer super-resolution imaging during its development. As a type of wave accompanying ultrasonic guided wave damage detection, the transient wave has had the potential to achieve super-resolution imaging in recent years due to its high wave number and sub-wavelength characteristics. In order to overcome its spatial attenuation characteristics, this study constructs a periodic plate-column structure metamaterial. By utilizing its resonance with sub-wavelength Bloch modes at specific frequencies and the interaction with transient waves carrying sub-wavelength information, the wave carrying sub-wavelength signals is amplified, transformed, and transmitted to the far field, thereby achieving super-resolution imaging. The dispersion characteristics of the periodic plate-column structure were simulated and experimentally investigated. The super-resolution imaging effect of the periodic plate-column structure metamaterial was simulated using the time-reversal imaging method and experimentally validated, providing a basis for achieving damage super-resolution imaging with periodic plate-column structures.

Aiming at the main problems existing in the jumping robot, combined with the galago senegalensis monkey's characteristics of small sizes, stable and explosive jumping, a kind of galago senegalensis monkey single leg jumping robot is proposed in this study, and its main structure and control system are designed. Based on the principle of the Stephenson's six-bar linkage, a planar eight-bar linkage for the leg of simulating galago senegalensis monkey robot is designed, and its trajectory is optimized to obtain the bar length parameters with the best jumping ability. The three directions of the robot's jumping are controlled and adjusted, and the double closed-loop feedback control system is used to ensure the stability of the robot's attitude when taking off, soaring in the air, and landing on the ground. Finally, the physical verification model of the robot is established. The total weight is only 395.5 g, and the overall height is 250 mm. The experimental results show that the simulating single leg robot can achieve continuous and stable jumping, the highest jumping speed can reach 20 m/s, and the response time at a jumping height of 100 mm is 0.1 s.

Abstract Supported metal clusters comprising of well-tailored low-nuclearity heteroatoms have great potentials in catalysis owing to the maximized exposure of active sites and metal synergy. However, atomically precise design of these architectures is still challenging for the lack of practical approaches. Here, we report a defect-driven nanostructuring strategy through combining defect engineering of nitrogen-doped carbons and sequential metal depositions to prepare a series of Pt and Mo ensembles ranging from single atoms to sub-nanoclusters. When applied in continuous gas-phase decomposition of formic acid, the low-nuclearity ensembles with unique Pt3Mo1N3 configuration deliver high-purity hydrogen at full conversion with unexpected high activity of 0.62 molHCOOH molPt −1 s−1 and remarkable stability, significantly outperforming the previously reported catalysts. The remarkable performance is rationalized by a joint operando dual-beam Fourier transformed infrared spectroscopy and density functional theory modeling study, pointing to the Pt-Mo synergy in creating a new reaction path for consecutive HCOOH dissociations.

Abstract A novel 1440‐V 4H‐SiC accumulation mode MOSFET (ACCUFET) with ultra‐low specific on‐resistance and improved reverse recovery performance is proposed in this article. As for the proposed SiC ACCUFET, the channel region can be completely depleted by the P‐type heavily doped polysilicon gate to build an electron barrier and realize a normally‐off device. And a Schottky barrier diode (SBD) is integrated below the trench gates on both sides, which brings the feasibility of realizing reverse conduction function of the proposed ACCUFET. Also, the p‐shield regions under the Schottky contact metal provide a good electric field shielding effect for the gate oxide. Compared with the conventional SiC trench MOSFET, the numerical simulation results show that the specific on‐resistance (Ron,sp) of the proposed ACCUFET is reduced by more than 64%. The high‐frequency figures‐of‐merit HFOM [Ron,sp × Cgd] and HFOM [Ron,sp × Qgd] of the proposed device are improved by 53.19% and 58.74%, respectively. The reverse recovery time (trr), and reverse recovery charge (Qrr) are reduced by 23.28% and 82.73%, respectively. In addition, the results also indicate that the proposed device has a better latch‐up immunity compared with the conventional SiC trench MOSFET. The excellent device performance and the simple manufacturing process provide a good prospect for the application of the proposed device.

Installing multi-camera systems and inertial measurement units (IMUs) in self-driving cars, micro aerial vehicles, and robots is becoming increasingly common. An IMU provides the vertical direction, allowing coordinate frames to be aligned in a common direction. The degrees of freedom (DOFs) of the rotation matrix are reduced from 3 to 1. In this paper, we propose a globally optimal solver to calculate the relative poses and scale of generalized cameras with a known vertical direction. First, the cost function is established to minimize algebraic error in the least-squares sense. Then, the cost function is transformed into two polynomials with only two unknowns. Finally, the eigenvalue method is used to solve the relative rotation angle. The performance of the proposed method is verified on both simulated and KITTI datasets. Experiments show that our method is more accurate than the existing state-of-the-art solver in estimating the relative pose and scale. Compared to the best method among the comparison methods, the method proposed in this paper reduces the rotation matrix error, translation vector error, and scale error by 53%, 67%, and 90%, respectively.

Abstract 5-Hydroxymethylfurfural (HMF) is a versatile platform chemical derived from the dehydration of renewable carbohydrates (typically glucose/fructose-based monosaccharides, oligosaccharides, and polysaccharides). Some useful compounds, such as 2,5-furandimethanol (FDM), 2,5-dimethylfuran (DMF) and 2,5-dimethyltetrahydrofuran (DMTHF), have been synthesized by reduction of HMF. Among these, FDM is a promising diol and can be further converted towards fine chemicals, liquid fuels and polymer materials. In this review, some typical catalytic systems for the synthesis of FDM from both HMF and carbohydrates were summarized. The discussion focused on controlling the reaction networks for the reduction of HMF. The reaction mechanisms and the stability of the catalysts were introduced briefly. Last but not least, the prospects of effective production of FDM were discussed as well.

5-Hydroxymethylfurfural (HMF) is a key platform compound that can be produced by the dehydration of typical carbohydrates like glucose and fructose. Among the derivatives of HMF, 5-ethoxymethylfurfural (EMF) is the etherification product of HMF with ethanol. Owing to some advantages (i.e., high energy density), EMF has been regarded as a potential liquid fuel. Therefore, catalytic conversion of HMF and fructose to EMF is of significance, especially using heterogeneous catalysts. In this paper, we demonstrated the preparation of biomass-based catalysts for the synthesis of EMF from HMF and fructose. Some sulfonated biochar catalysts were prepared by the carbonization of biomass-based precursors at high temperature in N2, followed by the subsequent sulfonation process employing concentered H2SO4 as sulfonation reagent. The obtained catalysts were characterized by scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), and element analysis. The catalytic conversion of HMF to EMF was carried out in ethanol, providing a 78% yield with complete conversion at 120 °C. The catalytic activity of the used catalyst showed slight decrease for the etherification of HMF. Moreover, the catalysts were effective for the direct conversion of fructose towards EMF in 64.9% yield. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Abstract Introduction Current guidelines suggest that regular aerobic training might lower blood pressure in hypertensive individuals. However, evidence linking resistant hypertension (RH) with total daily physical activity (PA), including work-, transport-, and recreation-related PA, is limited. Therefore, this study assessed the association between daily PA and RH. Method A cross-sectional study was conducted using data acquired from a nationwide survey in the US (the National Health and Nutrition Examination Survey, NHANES). The weighted prevalence of RH was calculated, and moderate and vigorous daily PA was assessed using the Global Physical Activity Questionnaire (GPAQ). A multivariate logistic regression model determined the association between daily PA and RH. Results A total of 8,496 treated hypertension patients were identified, including 959 RH cases. The unweighted prevalence of RH among treated hypertension cases was 11.28%, while the weighted prevalence was 9.81%. Participants with RH had a low rate of recommended PA levels (39.83%), and daily PA and RH were significantly associated. PA exhibited significant dose-dependent trends with a low probability of RH (p-trends

BackgroundThe survival for many children with relapsed/refractory cancers remains poor despite advances in therapies. Arginine metabolism plays a key role in the pathophysiology of a number of pediatric cancers. We report the first in child study of a recombinant human arginase, BCT-100, in children with relapsed/refractory hematological, solid or CNS cancers.ProcedurePARC was a single arm, Phase I/II, international, open label study. BCT-100 was given intravenously over one hour at weekly intervals. The Phase I section utilized a modified 3 + 3 design where escalation/de-escalation was based on both the safety profile and the complete depletion of arginine (defined as adequate arginine depletion; AAD