To support multi-source data stream generated from Internet of Things devices, edge computing emerges as a promising computing pattern with low latency and high bandwidth compared to cloud computing. ...To enhance the performance of edge computing within limited communication and computation resources, we study a cloud-edge-end computing architecture, where one cloud server and multiple computational access points can collaboratively process the compute-intensive data streams that come from multiple sources. Moreover, a multi-source environment is considered, in which the wireless channel and the characteristic of the data stream are time-varying. To adapt to the dynamic network environment, we first formulate the optimization problem as a markov decision process and then decompose it into a data stream offloading ratio assignment sub-problem and a resource allocation sub-problem. Meanwhile, in order to reduce the action space, we further design a novel approach that combines the proximal policy optimization (PPO) scheme with convex optimization, where the PPO is used for the data stream offloading assignment, while the convex optimization is employed for the resource allocation. The simulated outcomes in this work can help the development of the application of the multi-source data stream.
Due to the limited transmission capabilities of terrestrial intelligent devices within the Internet of Remote Things (IoRT), this paper proposes an optimization scheme aimed at enhancing data ...transmission rate while ensuring communication reliability. This scheme focuses on multi-unmanned aerial vehicle (UAV)-assisted IoRT data communication within the satellite–aerial–terrestrial integrated network (SATIN), which is one of the key technologies for the sixth generation (6G) networks. To optimize the system’s data transmission rate, we introduce a multi-dimensional coverage and power optimization (CPO) algorithm, rooted in the block coordinate descent (BCD) method. This algorithm concurrently optimizes various parameters, including the number and deployment of UAVs, the correlation between IoRT devices and UAVs, and the transmission power of both devices and UAVs. To ensure comprehensive coverage of a large-scale randomly distributed array of terrestrial devices, combined with machine learning algorithm, we present the Dynamic Deployment based on
K
-means (DDK) algorithm. Additionally, we address the non-convexity challenge in resource allocation for transmission power through variable substitution and the successive convex approximation technique (SCA). Simulation results substantiate the remarkable efficacy of our CPO algorithm, showcasing a maximum 240% improvement in the uplink transmission rate of IoRT data compared to conventional methods.
Effective utilization coefficient of farmland irrigation water is an important index for water-saving level evaluation. Tracked calculation of effective utilization coefficients of farmland ...irrigation water as well as quantitative and qualitative analyses in terms of its scientificity and rationality have a guiding role in sustainable development of water-saving irrigation. This paper sets out to calculate the effective utilization coefficients of farmland irrigation water in Guizhou Province in 2019 and evaluate rationality of the results. More than that, some internal factors influencing utilization coefficients are also investigated, and relevant proposals are put forward, in a view to providing technical support for water-saving irrigation planning and scientific water distribution.
China’s forests play a vital role in the global carbon cycle through the absorption of atmospheric CO2 to mitigate climate change caused by the increase of anthropogenic CO2. It is essential to ...evaluate the carbon sink potential (CSP) of China’s forest ecosystem. Combining NDVI, field-investigated, and vegetation and soil carbon density data modeled by process-based models, we developed the state-of-the-art learning ensembles model of process-based models (the multi-model random forest ensemble (MMRFE) model) to evaluate the carbon stocks of China’s forest ecosystem in historical (1982–2021) and future (2022–2081, without NDVI-driven data) periods. Meanwhile, we proposed a new carbon sink index (CSindex) to scientifically and accurately evaluate carbon sink status and identify carbon sink intensity zones, reducing the probability of random misjudgments as a carbon sink. The new MMRFE models showed good simulation results in simulating forest vegetation and soil carbon density in China (significant positive correlation with the observed values, r = 0.94, P < 0.001). The modeled results show that a cumulative increase of 1.33 Pg C in historical carbon stocks of forest ecosystem is equivalent to 48.62 Bt CO2, which is approximately 52.03% of the cumulative increased CO2 emissions in China from 1959 to 2018. In the next 60 years, China’s forest ecosystem will absorb annually 1.69 (RCP45 scenario) to 1.85 (RCP85 scenario) Bt CO2. Compared with the carbon stock in the historical period, the cumulative absorption of CO2 by China’s forest ecosystem in 2032–2036, 2062–2066, and 2077–2081 are approximately 11.25–39.68, 110.66–121.49 and 101.31–111.11 Bt CO2, respectively. In historical and future periods, the medium and strong carbon sink intensity regions identified by the historical CSindex covered 65% of the total forest area, cumulative absorbing approximately 31.60 and 65.83–72.22 Bt CO2, respectively. In the future, China’s forest ecosystem has a large CSP with a non-continuous increasing trend. However, the CSP should not be underestimated. Notably, the medium carbon sink intensity region should be the priority for natural carbon sequestration action. This study not only provides an important methodological basis for accurately estimating the future CSP of forest ecosystem but also provides important decision support for future forest ecosystem carbon sequestration action.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Limited energy has always been an important factor restricting the development of wireless sensor networks. The unbalanced energy consumption of nodes will accelerate the death of some nodes. To ...solve the above problems, an adaptive routing algorithm for energy collection sensor networks based on distributed energy saving clustering (DEEC) is proposed. In each hop of data transmission, the optimal mode is adaptively selected from four transmission modes: single-hop cooperative, multi-hop cooperative, single-hop non-cooperative and multi-hop non-cooperative, so as to reduce and balance the energy consumption of nodes. The performance of the proposed adaptive multi-mode transmission method and several benchmark schemes are evaluated and compared by computer simulation, where a few performance metrics such as the network lifetime and throughput are adopted. The results show that, the proposed method can effectively reduce the energy consumption of the network and prolong the network lifetime; it is superior to various benchmark schemes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Brillouin spectroscopy is a powerful tool that enables a non-destructive and non-invasive assessment of the mechanical properties of a material. In recent years, virtual imaging phase array (VIPA) ...spectrometers have been widely used to perform these measurements. At present, few studies that VIPA spectrometers coupled with charge-coupled device (CCD) cameras have been employed to accurately measure Brillouin scattering spectra. In this report, a simple and accurate method to analyze Brillouin spectra and measure the Brillouin shift is proposed. The spectral data of water and olive oil samples were obtained by the stimulated Brillouin scattering system to verify the feasibility of the method. Furthermore, the factors affecting the Brillouin shift have been analyzed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The virtual bright fringes method (VBFM) has been here designed to analyze the spectrum signal of Brillouin scattering in water using virtually imaged phased array (VIPA) etalon and an intensified ...charge-coupled device (ICCD) camera. VBFM is based on the principle of multiple-beam interference with a plane-parallel plate and, thus, only needs the output of the sample to calculate the Brillouin Stokes frequency shift. Moreover, this method substantially reduces the experimental requirements and simplifies the experimental processing. In addition, the capability of this new method has been confirmed by processing experimental data from stimulated Brillouin scattering spectra in water. Our results demonstrated that the experimental results processed by VBFM were in good agreement with the theoretical values. Indeed, VBFM provides a feasible scheme for the measurement of Brillouin Stokes frequency shift with sub-GHz accuracy of 10MHz. VBFM facilitates a broader application of Brillouin scattering, including the measurement of liquid materials and the elastography of biological tissue.
Premature ovarian failure (POF) features an upward incidence nowadays, and the human umbilical cord mesenchymal stem cells (hUC‐MSCs)‐derived exosomes (MSC‐Exos) have shown applied values in the ...recovery of ovarian function. Here, a novel exosome‐encapsulated microcarrier prepared by microfluidic technology for ovarian repair after chemotherapy damage is presented. The exosomes derived from lipopolysaccharide (LPS)‐preconditioned hUC‐MSCs are encapsulated with hyaluronic acid methacryloyl (HAMA) via microfluidic electrospray, which is named HAMA/MSC‐Exos. Attributing to the biocompatibility and semipermeable property of HAMA, the encapsulated exosomes show great viability and controllable release behavior from HAMA. It is demonstrated that in situ transplantation of HAMA/MSC‐Exos can rescue ovarian functions of cyclophosphamide‐induced ovarian failure in mice by increasing ovarian volume, improving the number of antral follicles and restoring fertility. It is believed that the transplantation of HAMA/MSC‐Exos will provide a new concept for the treatment of POF in clinical practice.
The exosomes derived from lipopolysaccharide (LPS)‐preconditioned hUC‐MSCs are encapsulated with hyaluronic acid methacryloyl (HAMA) via microfluidic electrospray, which is named HAMA/MSC‐Exos. It is demonstrated that in situ transplantation of HAMA/MSC‐Exos can rescue ovarian functions of cyclophosphamide‐induced ovarian failure in mice by increasing ovarian volume, improving the number of antral follicles, and restoring fertility.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Periodontitis is a chronic infectious disease that alters the cellular microenvironment and promotes bone absorption. Bone morphogenetic protein 9 (BMP9) serves an important role in proliferation and ...differentiation, and tumor necrosis factor‑alpha (TNF‑α) is an important contributor to bone resorption. The present study aimed to investigate the effect of osteogenic differentiation in the presence of BMP9 and TNF‑α in rat follicle stem cells (rDFCs). rDFCs were transfected with adenoviruses expressing BMP9 (AdBMP9) and the expression levels of important proteins BMP9, β‑catenin, glycogen synthase kinase 3β (GSK3β), phosphorylated‑GSK3β, calcium/calmodulin dependent protein kinase II and nemo like kinase were determined using western blotting. The effect of osteogenesis was analyzed using reverse transcription‑quantitative PCR, in addition to alkaline phosphatase, Alizarin Red S, and hematoxylin and eosin staining methods. The results of the present study revealed that TNF‑α activated the canonical Wnt signaling pathway and suppressed osteogenesis. High concentrations of Dickkopf 1 (DKK1) reduced the osteogenic differentiation of AdBMP9‑transduced rDFCs, whereas low concentrations of DKK1 promoted BMP9‑induced bone formation, which was discovered to partially act via the canonical and non‑canonical Wnt signaling pathways. In conclusion, the findings of the present study suggested that the enhanced promoting effect of BMP9 alongside the treatment with low concentrations of DKK1 may be useful for treating periodontitis bone absorption.
Periodontitis is a chronic infectious disease that alters the cellular microenvironment and promotes bone absorption. Bone morphogenetic protein 9 (BMP9) serves an important role in proliferation and ...differentiation, and tumor necrosis factor-alpha (TNF-alpha) is an important contributor to bone resorption. The present study aimed to investigate the effect of osteogenic differentiation in the presence of BMP9 and TNF-alpha in rat follicle stem cells (rDFCs). rDFCs were transfected with adenoviruses expressing BMP9 (AdBMP9) and the expression levels of important proteins BMP9, beta-catenin, glycogen synthase kinase 3beta (GSK3beta), phosphorylated-GSK3beta, calcium/calmodulin dependent protein kinase II and nemo like kinase were determined using western blotting. The effect of osteogenesis was analyzed using reverse transcription-quantitative PCR, in addition to alkaline phosphatase, Alizarin Red S, and hematoxylin and eosin staining methods. The results of the present study revealed that TNF-alpha activated the canonical Wnt signaling pathway and suppressed osteogenesis. High concentrations of Dickkopf 1 (DKK1) reduced the osteogenic differentiation of AdBMP9-transduced rDFCs, whereas low concentrations of DKK1 promoted BMP9-induced bone formation, which was discovered to partially act via the canonical and non-canonical Wnt signaling pathways. In conclusion, the findings of the present study suggested that the enhanced promoting effect of BMP9 alongside the treatment with low concentrations of DKK1 may be useful for treating periodontitis bone absorption. Key words: rat follicle stem cells, bone morphogenetic protein, tumor necrosis factor-alpha, Wnt signaling, osteogenic differentiation
PDF
