Recognizing coal and coal gangue is an important part of the coal industry and is mainly conducted via human sorting at present. Consequently, considerable manpower is needed, which adds a burden to ...enterprises and results in low efficiency. As an important branch of artificial intelligence, deep learning has been widely applied in many fields, especially in machine vision and voice recognition, its performance is greatly improved compared with the performances of traditional learning methods, and it also has good a transfer learning ability. This paper proposed an improved YOLOv4 algorithm as a classic deep learning method for the intelligent and highly accurate recognition of coal and coal gangue. Compared to other algorithms, YOLOv4 has a better anchor value by applying cluster analysis to different data sets, a good anti-interference ability due to using the Laplacian operator and Gaussian filter to reduce the impacts from mine dust and shock and acquires richer detailed information by increasing the number of layers of the feature pyramid. The experimental results show that compared with the other four algorithms of YOLOv4, YOLOv3, SSD and Faster-RCNN, the improved YOLOv4 proposed in this paper exhibits better detection accuracy, a better detection speed and robust performance.
Aim: Monocyte-to-high-density lipoprotein ratio (MHR) recently emerged as an inflammatory marker and has been reported to be a novel prognostic indicator of cardiovascular diseases. However, the ...relationship between MHR and prognosis of acute ischemic stroke (AIS) remains unclear. Methods: Consecutive AIS patients were prospectively identified from January 2015 to December 2017. Functional outcome was evaluated by the modified Rankin Scale (mRS). Poor outcome was defined as of mRS 3-6. Multivariate logistic regression analysis was conducted to evaluate the relationship between MHR and poor outcome. Results: A total of 1090 AIS patients within 24 hours of the onset of symptoms were recruited. MHR was higher in poor outcome group compared to that in good outcome group 0.53 (0.37-0.69) vs. 0.48 (0.33-0.60), P=0.007. Multivariate logistic regression analysis indicated that higher MHR level was independently associated with the poor outcome at 3 months (OR 2.58, 95% CI, 1.21-5.51, P=0.015), especially the stroke subtype of large artery atherosclerosis (OR 2.52, 95% CI, 1.03-6.19, P=0.034). Receiver operating curve (ROC) analysis showed that the area under the ROC curves for MHR was 0.67 and the best predictive cutoff value of MHR was 0.51,with a sensitivity of 62.3% and a specificity of 66.5%. Conclusions: MHR may be a significant and independent predictor of poor functional outcome in patients with AIS.
The high open‐circuit voltage (Voc) loss arising from insufficient surface passivation is the main factor that limits the efficiency of current lead sulfide colloidal quantum dots (PbS CQDs) solar ...cell. Here, synergistic passivation is performed in the direct synthesis of conductive PbS CQD inks by introducing multifunctional ligands to well coordinate the complicated CQDs surface with the thermodynamically optimal configuration. The improved passivation effect is intactly delivered to the final photovoltaic device, leading to an order lower surface trap density and beneficial doping behavior compared to the control sample. The obtained CQD inks show the highest photoluminescence quantum yield (PLQY) of 24% for all photovoltaic PbS CQD inks, which is more than twice the reported average PLQY value of ≈10%. As a result, a high Voc of 0.71 V and power conversion efficiency (PCE) of 13.3% is achieved, which results in the lowest Voc loss (0.35 eV) for the reported PbS CQD solar cells with PCE >10%, comparable to that of perovskite solar cells. This work provides valuable insights into the future CQDs passivation strategies and also demonstrates the great potential for the direct‐synthesis protocol of PbS CQDs.
Synergistic passivation is performed in the direct synthesis of conductive lead sulfide colloidal quantum dot (PbS CQD) inks. The improved passivation effect is intactly delivered to the final photovoltaic device, leading a high open‐circuit voltage (Voc)) of 0.71 V and efficiency of 13.3%, which results in the lowest Voc loss (0.35 eV) for the reported PbS CQD solar cells.
Joint pain is the defining symptom of osteoarthritis (OA) but its origin and mechanisms remain unclear. Here, we investigated an unprecedented role of osteoclast-initiated subchondral bone remodeling ...in sensory innervation for OA pain. We show that osteoclasts secrete netrin-1 to induce sensory nerve axonal growth in subchondral bone. Reduction of osteoclast formation by knockout of receptor activator of nuclear factor kappa-B ligand (Rankl) in osteocytes inhibited the growth of sensory nerves into subchondral bone, dorsal root ganglion neuron hyperexcitability, and behavioral measures of pain hypersensitivity in OA mice. Moreover, we demonstrated a possible role for netrin-1 secreted by osteoclasts during aberrant subchondral bone remodeling in inducing sensory innervation and OA pain through its receptor DCC (deleted in colorectal cancer). Importantly, knockout of Netrin1 in tartrate-resistant acid phosphatase-positive (TRAP-positive) osteoclasts or knockdown of Dcc reduces OA pain behavior. In particular, inhibition of osteoclast activity by alendronate modifies aberrant subchondral bone remodeling and reduces innervation and pain behavior at the early stage of OA. These results suggest that intervention of the axonal guidance molecules (e.g., netrin-1) derived from aberrant subchondral bone remodeling may have therapeutic potential for OA pain.
Osteoarthitis (OA) is the most common aging-related joint pathology; the aging process results in changes to joint tissues that ultimately contribute to the development of OA. Articular chondrocytes ...exhibit an aging-related decline in their proliferative and synthetic capacity. Sirtuin 1 (SIRT 1), a longevity gene related to many diseases associated with aging, is a nicotinamide adenine dinucleotide (NAD
)-dependent protein deacetylase and master metabolic regulator. Along with its natural activator resveratrol, SIRT 1 actively participates in the OA pathological progress. SIRT 1 expression in osteoarthritic cartilage decreases in the disease progression of OA; it appears to play a predominantly regulatory role in OA. SIRT 1 can regulate the expression of extracellular matrix (ECM)-related proteins; promote mesenchymal stem cell differentiation; play anti-catabolic, anti-inflammatory, anti-oxidative stress, and anti-apoptosis roles; participate in the autophagic process; and regulate bone homeostasis in OA. Resveratrol can activate SIRT 1 in order to inhibit OA disease progression. In the future, activating SIRT 1 via resveratrol with improved bioavailability may be an appropriate therapeutic approach for OA.
The instantaneous vital sign rates, which are related to physiological dynamics, are important indicators of human health condition. This paper presents a noncontact way to measure the human ...instantaneous vital signs using digital-intermediate frequency (IF) Doppler radar. The synchrosqueezing transform-based algorithm has been proposed to get a concentrated time-frequency (TF) distribution, so that the high-resolution instantaneous heartbeat and respiratory rates and the time-domain signals can be acquired. Moreover, the developed radar with customized radio frequency module employs the direct IF sampling technique to achieve high sensitivity to capture the tiny vital sign variations. Experiments with different human subjects and physiological conditions have been carried out. Compared with the landmark-based method and traditional TF algorithms, the results show that instantaneous vital signs can be acquired more accurately within 3 m at a -13 dBm transmit power by the proposed method. Therefore, the radar can be used for evaluating the physiological dynamics and assessing health condition.
In this paper, mesoporous antimony doped tin oxide (ATO) microspheres are synthesized via a solvothermal method from a methanol system with the surfactant followed by a thermal treatment process. ...Morphology studies reveal that the spherical products obtained by polyvinylpyrrolidone (PVP) templating result in a higher uniformity in size. Such obtained ATO microspheres with a secondary particle size ranging between 200 and 800 nm consist of packed tiny nanocrystals and have high specific surface area (∼98 m2 g–1). The effect of Sb doping on the structural and electrical properties of SnO2 microspheres is studied. Because of the substitution of Sn4+ with Sb5+ accompanied by forming a shallow donor level close to the conduction band of SnO2, a lower resistivity of powder pellet can be achieved, which corresponds to the spectrally selective property of films. The application of ATO microspheres provides an example of transparent coatings; depending on Sb concentration in SnO2 and solid content of coatings, transparent films with tunable solar-heat shielding property are obtained.
•A theoretical PbSe QDSC model was established through diffusion-drift method.•The optional optimization strategies of PbSe QDSCs were theoretically discussed.•This method can provide a deeper ...understanding of the working mechanism of QDSCs.
Lead selenide quantum dots (PbSe QDs), as promising active absorbers, have received considerable attention in solar cells. However, the performance of PbSe QD-based solar cells (PbSe QDSCs) still lags behind that of c-Si and perovskite solar cells mainly due to non-radiative and resistive losses. To investigate the limitation of PbSe QDSCs, we established a theoretical model based on the performance of the state-of-the-art PbSe QDSCs through diffusion-drift theory and systematically discussed the optional strategies for optimizing the efficiency of PbSe QDSCs. The optimizations were initially carried out in term of absorber layer thickness, defect densities in absorber layer and interface defect layer (IDL), thus yielding a power conversion efficiency (PCE) of 15.25% with open-circuit voltage (Voc) of 0.64 V and fill factor (FF) of 74.49% in PbSe QDSCs. After the modifications of the doping concentrations of charge transport layers and the band alignment in solar device, the PbSe QDSCs can achieve over 30% efficiency with a ∼80% and 32 % improvement in Voc and FF, respectively. Our findings gained here provide effective experimental guidelines and pave the way for PbSe QDSCs to approach their theoretical efficiency limit.
Although studies have examined the association between dietary magnesium intake and health outcome, the results are inconclusive. Here, we conducted a dose-response meta-analysis of prospective ...cohort studies in order to investigate the correlation between magnesium intake and the risk of cardiovascular disease (CVD), type 2 diabetes (T2D), and all-cause mortality.
PubMed, EMBASE, and Web of Science were searched for articles that contained risk estimates for the outcomes of interest and were published through May 31, 2016. The pooled results were analyzed using a random-effects model.
Forty prospective cohort studies totaling more than 1 million participants were included in the analysis. During the follow-up periods (ranging from 4 to 30 years), 7678 cases of CVD, 6845 cases of coronary heart disease (CHD), 701 cases of heart failure, 14,755 cases of stroke, 26,299 cases of T2D, and 10,983 deaths were reported. No significant association was observed between increasing dietary magnesium intake (per 100 mg/day increment) and the risk of total CVD (RR: 0.99; 95% CI, 0.88-1.10) or CHD (RR: 0.92; 95% CI, 0.85-1.01). However, the same incremental increase in magnesium intake was associated with a 22% reduction in the risk of heart failure (RR: 0.78; 95% CI, 0.69-0.89) and a 7% reduction in the risk of stroke (RR: 0.93; 95% CI, 0.89-0.97). Moreover, the summary relative risks of T2D and mortality per 100 mg/day increment in magnesium intake were 0.81 (95% CI, 0.77-0.86) and 0.90 (95% CI, 0.81-0.99), respectively.
Increasing dietary magnesium intake is associated with a reduced risk of stroke, heart failure, diabetes, and all-cause mortality, but not CHD or total CVD. These findings support the notion that increasing dietary magnesium might provide health benefits.
In this study, we systematically explored the mixed-cation perovskite Cs x (MA0.4FA0.6)1–x PbI3 fabricated via sequential introduction of cations. The details of the effects of Cs+ on the fabrication ...and performance of inorganic–organic mixed-cation perovskite solar cells examined in detail in this study are beyond the normal understanding of the adjusting band gap. It is found that a combined intercalation of Cs+ and dimethyl sulfoxide (DMSO) in PbI2–DMSO precursor film formed a strong and steady coordinated intermediate phase to retard PbI2 crystallization, suppress yellow nonperovskite δ-phase, and obtain a highly reproducible perovskite film with less defects and larger grains. The Cs-contained triple-cation-mixed perovskite Cs0.1(MA0.4FA0.6)0.9PbI3 devices yield over 20% reproducible efficiencies, superior stabilities, and fill factors of around 0.8 with a very narrow distribution.
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