Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated b...Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated bed nets (LLINs), full ownership and optimal use is still limited. In 2021, over a million LLINs were made available for distribution in the South West Region. However, the current situation of malaria has not yet been ascertained following the 2021 mass distribution campaign (MDC). Therefore, the aim of this study was to determine LLIN ownership, coverage, usage and the prevalence of malaria following the 2021 MDC in the Tiko Health District (THD), South West Region of Cameroon. A cross-sectional study was carried from May 1 to 27, 2022 in which a multi-stage sampling technique was used to enroll eligible participants. Data were collected from household heads using questionnaires and capillary blood samples collected from consented household members were used to test for malaria. Data were analyzed using SPSS version 25 at 0.05 significance level. From the 150 households surveyed, 96 (64.0%) owned a mosquito net before the recent MDC. There was an overall significant increase (p p = 0.644) in LLINs ownership between areas where door-to-door (79.5%) and fixed “Hit and Run” (75.8%) strategies were used in the distribution of LLINs in THD. The prevalence of malaria was 10.2%. The regular use of LLINs was significantly associated (p = 0.007) with low malaria prevalence. The 2021 MDC had an impact on malaria prevalence in those who properly used them.展开更多
Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a s...Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a single prediction model is hard to capture temporal features effectively, resulting in diminished predictionaccuracy. In this study, a hybrid deep learning framework that integrates attention mechanism, convolution neuralnetwork (CNN), improved chaotic particle swarm optimization (ICPSO), and long short-term memory (LSTM), isproposed for short-term household load forecasting. Firstly, the CNN model is employed to extract features fromthe original data, enhancing the quality of data features. Subsequently, the moving average method is used for datapreprocessing, followed by the application of the LSTM network to predict the processed data. Moreover, the ICPSOalgorithm is introduced to optimize the parameters of LSTM, aimed at boosting the model’s running speed andaccuracy. Finally, the attention mechanism is employed to optimize the output value of LSTM, effectively addressinginformation loss in LSTM induced by lengthy sequences and further elevating prediction accuracy. According tothe numerical analysis, the accuracy and effectiveness of the proposed hybrid model have been verified. It canexplore data features adeptly, achieving superior prediction accuracy compared to other forecasting methods forthe household load exhibiting significant fluctuations across different seasons.展开更多
Hepatocellular carcinoma(HCC) is the predominant subject of liver malignancies which arouse global concern. Advanced studies have found that long noncoding RNAs(lnc RNAs) are differentially expressed in HCC and implic...Hepatocellular carcinoma(HCC) is the predominant subject of liver malignancies which arouse global concern. Advanced studies have found that long noncoding RNAs(lnc RNAs) are differentially expressed in HCC and implicate they may play distinct roles in the pathogenesis and metastasis of HCC. However, the underlying mechanisms remain largely unclear. In this review, we summarized the functions and mechanisms of those known aberrantly expressed lncR NAs identified in human HCC tissues. We hope to enlighten more comprehensive researches on the detailed mechanisms of lncR NAs and their application in clinic, such as being used as diagnostic and prognostic biomarkers and the targets for potential therapy. Although studies on lncR NAs in HCC are still deficient, an improved understanding of the roles played by lncR NAs in HCC will lead to a much more effective utilization of those lnc RNAs as novel candidates in early detection, diagnosis, prevention and treatment of HCC.展开更多
The upper reaches of the Minjiang River are in the eastern margin of the Tibetan Plateau,where active faults are well developed and earthquakes frequently occur.Anomalous climate change and the extremely complex geome...The upper reaches of the Minjiang River are in the eastern margin of the Tibetan Plateau,where active faults are well developed and earthquakes frequently occur.Anomalous climate change and the extremely complex geomechanical properties of rock and soil have resulted in a number of geohazards.Based on the analysis of remote sensing interpretations,geological field surveys,geophysical prospecting and geological dating results,this paper discusses the developmental characteristics of the Gamisi ancient landslide in Songpan County,Sichuan Province,and investigates its geological age and formation mechanism.This study finds that the Gamisi ancient landslide is in the periglacial region of the Minshan Mountain and formed approximately 25 ka BP.The landslide initiation zone has a collapse and slide zone of approximately 22.65×106–31.7×106 m3 and shows a maximum sliding distance of approximately 1.42 km,with an elevation difference of approximately 310 m between the back wall of the landslide and the leading edge of the accumulation area.The landslide movement was characterized by a high speed and long runout.During the sliding process,the landslide body eroded and dammed the ancient Minjiang River valley.The ancient river channel was buried 30-60 m below the surface of the landslide accumulation area.Geophysical prospecting and drilling observations revealed that the ancient riverbed was approximately 80-100 m thick.After the dam broke,the Minjiang River was migrated to the current channel at the leading edge of the landslide.The Gamisi ancient landslide was greatly affected by the regional crustal uplift,topography,geomorphology and paleoclimatic change.The combined action of periglacial karstification and climate change caused the limestone at the rear edge of the landslide fractured,thus providing a lithological foundation for landslide occurrence.Intense tectonic activity along the Minjiang Fault,which runs through the middle and trailing parts of the Gamisi ancient landslide,may have been the main factor inducing landsliding.Studying the Gamisi ancient landslide is of great significance for investigating the regional response to paleoclimatic change and geomorphologic evolution of the Minjiang Fault since the late Pleistocene and for disaster prevention and mitigation.展开更多
According to the investigations on the oil and gas pipelines such as the Lan-Cheng-Chong pipeline and the Southwest pipeline, there are two ways of laying pipeline: pipelines paralleling (approximately) to the main...According to the investigations on the oil and gas pipelines such as the Lan-Cheng-Chong pipeline and the Southwest pipeline, there are two ways of laying pipeline: pipelines paralleling (approximately) to the main slide direction and pipelines perpendicular (approximately) to the main slide direction. If earth-retaining walls have been built for pipelines paralleling to the main slide direction, they will prevent the lands from sliding; On the contrary, without earth-retaining walls, the sharp broken rocks in the backfilling soil will scratch the safeguard of the pipeline when the landslides take place. Pipelines perpendicular to the main slide direction can be classified into four types according to the relative positions between pipelines and landslides: Pipelines over the slide planes, pipelines inside the fracture strips of slide planes, pipelines below the slide planes and pipelines behind the backsides of landslides. The different dynamical mechanisms of the process in which landslide acts against pipelines are analyzed based on whether the pipelines are equipped with fixed frusta, because the sliding resistance depends on whether and how many fixed frusta are equipped and the distance between frusta.展开更多
The Eu (2+) and Dy (3+) codoped silicates,Ca_2MgSi_2O_7∶Eu (2+),Dy (3+),was synthesized,and its photoluminescence properties were studied with synchrotron radiation. Under synchrotron radiation excitation at 305 nm,o...The Eu (2+) and Dy (3+) codoped silicates,Ca_2MgSi_2O_7∶Eu (2+),Dy (3+),was synthesized,and its photoluminescence properties were studied with synchrotron radiation. Under synchrotron radiation excitation at 305 nm,only the characteristic emission from Eu (2+) was excited. But the characteristic emission from Dy (3+) was also found under 175 nm excitation,besides the characteristic emission of Eu (2+). The characteristic emission from Dy (3+) was detected in the Eu (2+) and Dy (3+) codoped long lasting phosphorescence materials,which indicates that Dy (3+) is still existed in the phosphors under continue excitation at 175 nm.展开更多
Long lasting phosphorescence (LLP) was observed in Eu2+, Ce3+ co-doped strontium borate glasses prepared under the reducing atmosphere due to the emission of both Eu2 + and Ce3+ . The methods of photoluminescence, the...Long lasting phosphorescence (LLP) was observed in Eu2+, Ce3+ co-doped strontium borate glasses prepared under the reducing atmosphere due to the emission of both Eu2 + and Ce3+ . The methods of photoluminescence, thermolu-minescence and phosphorescence were used to study the samples, and possible mechanism was suggested. The co-doping of Ce3 + ions poisoned the phosphorescence emission of Eu2 + because of the competition to obtain the trapped electron . The phosphorescence of Ce3 + in the sample decays more quickly than that of Eu2 + , which is suggested for the reason that the emission energy of Ce3 + is higher or the distance between Ce3 + and electron traps of the glasses is longer.展开更多
As an improvement of reported Y2O2S:Tb^3+, a white-light long-lasting phosphor: Y2O2S:Tb^3+, Sm^3+ was prepared by the solid-state reaction. The photo-luminescence spectra showed that the position and shape of T...As an improvement of reported Y2O2S:Tb^3+, a white-light long-lasting phosphor: Y2O2S:Tb^3+, Sm^3+ was prepared by the solid-state reaction. The photo-luminescence spectra showed that the position and shape of Tb^3+ and Sm^3+ emissions under UV excitation were similar in this host, which ensured a stable white emission color (daylight standard of IEC) under different excitations. The decay curves of co-doped samples indicated that the decay times of emissions of the two ions were close. The thermo-luminescence measurement suggested that the traps created by the doped Sm^3+ ions were helpful to postpone the white afterglow of co-doped samples. Therefore, the function of co-doped Sm^3+ ions was confirmed as improving the white emission colors of samples and acting as new trap centers.展开更多
A novel white light emitting long-lasting phosphor Cd1-xDyxSiO3 is reported in this letter. The Dy3+ doped CdSiO3 phosphor emits white light. The phosphorescence can be seen with the naked eye in the dark clearly ev...A novel white light emitting long-lasting phosphor Cd1-xDyxSiO3 is reported in this letter. The Dy3+ doped CdSiO3 phosphor emits white light. The phosphorescence can be seen with the naked eye in the dark clearly even after the 254 nm UV irradiation have been removed for about 30 min. In the emission spectrum of 5% Dy3+ doped CdSiO3 phosphor, there are two emission peaks of Dy3+, 580 nm (4F9/26H13/2) and 486 nm (4F9/26H15/2), as well as a broad band emission located at about 410 nm. All the three emissions form a white light with CIE chromaticity coordinates x=0.3874, y=0.3760 and the color temperature is 4000 K under 254 nm excitation. It indicated that this phosphor is a promising new luminescent material for practice application.展开更多
Long-lasting phosphor Y2O2S : Eu^3+ , Mg^2+ , Ti^4+ was synthesized by a flux method and their luminescence properties were investigated. The result indicates that the unit cell parameter c is linearly increased w...Long-lasting phosphor Y2O2S : Eu^3+ , Mg^2+ , Ti^4+ was synthesized by a flux method and their luminescence properties were investigated. The result indicates that the unit cell parameter c is linearly increased with the increase of Eu2O3 content in Y2O2S: Eu^3+ (0.01 ≤ x ≤0.10). On the other hand, the change of unit cell parameter a is not linear dependence. In the Y2O2S: Eu^3 + crystal structure, Eu^3+ ions only replaced Y^3 + ions' places in which it posited center position of c axis. With the increase of Eu2O3 content, the position of the strongest emission peak changed from 540 nm (5D1→^ 7F2 transition) to 626 nm (^5Do→^7TF2 transition), and the maximum intensity was obtained when x = 0.09 in Y2O2S: Eu^3+ (0.01 ≤x ≤0.10). This is due to the environment of trivalent europium in the crystal structure of Y2O2S. Doping with Mg^2+ or Ti^4+. ions alone cannot get the good long-lasting afterglow effect, whereas co-doping with Mg^2 + and Ti^4 + ions and excited with 365 nm ultraviolet light, a strong thermoluminesence peak appeared, red and orange long-lasting phosphorescence (LLP) was also observed and the phosphorescence lasted nearly 3 h in the light perception of the dark-adapted human eye (0.32 mcd·m^-2). Thus the LLP mechanism was analyzed.展开更多
A white long-lasting phosphor Ca2MgSi2O7:Dy3+ was prepared by the solid-state reaction. A strong band peaked at 260 nm was shown in the excitation spectrum of 578 nm emission, which might be attributed to the oxygen d...A white long-lasting phosphor Ca2MgSi2O7:Dy3+ was prepared by the solid-state reaction. A strong band peaked at 260 nm was shown in the excitation spectrum of 578 nm emission, which might be attributed to the oxygen deficiency of the host. After irradiated with 254 nm for 4 min, the white afterglow of the sample could be seen for 3 h. Moreover, the depths and frequency factors of trap centers were calculated from the thermo-luminescence curve of the sample, which indicated that the trap centers corresponding to the 414 K band were more helpful to the long-lasting phosphorescence.展开更多
A novel red long-lasting phosphor, (YxGd1-x)2O3:Eu3+, Sm3+, Si4+, Mg2+, was synthesized by the co-precipitation method using oxalate precipitation as the precursor. X-ray diffraction (XRD), scanning electroni...A novel red long-lasting phosphor, (YxGd1-x)2O3:Eu3+, Sm3+, Si4+, Mg2+, was synthesized by the co-precipitation method using oxalate precipitation as the precursor. X-ray diffraction (XRD), scanning electronic microscopy (SEM), integrated thermal analyzer (TG), and photoluminescence spectra (PL) as well as the ST-900PM weak light photometer were used to study the synthesis conditions, morphology, luminescence properties, and the decay time of the phosphor. The XRD results show that the products synthesized at 1400~C for 4 h have good crystallization without any detectable impurity phases. Based on the PL spectra, the optimal conditions are as the following. The molar ratios of Y3+ to Gd3+ and Eu3+ to Sm3+ are 2:8 and 3:1, respectively, and the contents of Mg2+ and SiO2 are 5mol% and 3mol%, respectively. The decay time monitored by the ST-900PM weak light photometer is 7200 s, increasing 44% and 100%, respectively, compared with the Eu3+ and Sm3+ single-doped phosphors. The results indicate that the energy transfer is from Sm3+ to Eu3+ ion, and Sm3+ is a good sensitizer to Eu3+.展开更多
Long lasting phosphorescence (LLP) and photo-stimulated long lasting phosphorescence (PSLLP) were observed in Tb^3+-doped strontium borosilicate glasses. The green phosphorescence arises fromf-f transitions of T...Long lasting phosphorescence (LLP) and photo-stimulated long lasting phosphorescence (PSLLP) were observed in Tb^3+-doped strontium borosilicate glasses. The green phosphorescence arises fromf-f transitions of Tb^3+ and can be observed with naked eyes in the dark for up to 10 hours after the irradiation with a UV lamp (λmax =254 nm) for 30 min at room temperature. The glass could re-emit LLP under the stimulation of a UV lamp (λmax=366 rim) for 60 seconds after the LLP disappeared. The re-emitted LLP is called PSLLP. The glass sample was characterized by the fluorescence and thermoluminescence spectra, respectively. The possible mechanism of the LLP and PSLLP was also discussed.展开更多
Mn^2+ doped ZnO-P2O5 glasses emit red fluorescence, which shows that Mn^2+ ion doped in zinc phosphate glass is octahedrally coordinated. Moreover, glass samples exhibit bright red long lasting phosphorescence (LLP...Mn^2+ doped ZnO-P2O5 glasses emit red fluorescence, which shows that Mn^2+ ion doped in zinc phosphate glass is octahedrally coordinated. Moreover, glass samples exhibit bright red long lasting phosphorescence (LLP) when the mole percent of ZnO are more than 60%. After turnoff the irradiation source of UV lamp peaking at 254 nm, the red phosphorescence can be observed for about 6 h in the limit of light perception for naked eyes (0.32 mcd/m^2). Photoluminescence (PL) spectra, LLP emission spectra and decay curves were detected. Increasing MnO or ZnO content, the phosphorescence intensity can be improved distinctly and the emission wavelength can be also adjusted from 595 nm to 628 nm. According to the structural characteristic of zinc phosphates glasses, we suggest that non-bridge oxygen (NBO) is probably related with the arising of LLE Meantime, the variation of crystal field intensity induced that the LLP emission wavelength red shifts.展开更多
A correct and timely fault diagnosis is important for improving the safety and reliability of chemical processes. With the advancement of big data technology, data-driven fault diagnosis methods are being extensively ...A correct and timely fault diagnosis is important for improving the safety and reliability of chemical processes. With the advancement of big data technology, data-driven fault diagnosis methods are being extensively used and still have considerable potential. In recent years, methods based on deep neural networks have made significant breakthroughs, and fault diagnosis methods for industrial processes based on deep learning have attracted considerable research attention. Therefore, we propose a fusion deeplearning algorithm based on a fully convolutional neural network(FCN) to extract features and build models to correctly diagnose all types of faults. We use long short-term memory(LSTM) units to expand our proposed FCN so that our proposed deep learning model can better extract the time-domain features of chemical process data. We also introduce the attention mechanism into the model, aimed at highlighting the importance of features, which is significant for the fault diagnosis of chemical processes with many features. When applied to the benchmark Tennessee Eastman process, our proposed model exhibits impressive performance, demonstrating the effectiveness of the attention-based LSTM FCN in chemical process fault diagnosis.展开更多
Insecticide treated nets (ITNs) play a pivotal role in the prevention and control of malaria. Conversely, inadequate levels of ownership, utilization and durability invariably compromise their efficacy. Operational pe...Insecticide treated nets (ITNs) play a pivotal role in the prevention and control of malaria. Conversely, inadequate levels of ownership, utilization and durability invariably compromise their efficacy. Operational performance of the KO-Tab 1-2-3 Long Lasting Insecticidal Nets (LLINs) was assessed using the World Health Organization (WHO) standard entomological and epidemiological procedures, and a pretested structured questionnaire. The median knock down time for Anopheles funestus s.l. was 30 minutes (95% CI 26.3 - 34.0). Post exposure mean mortality rates were 34% at one hour and 80.0% at 24 hours (OR = 0.13, P = 0.00002). Children between the ages of 1 - 4 years old exhibited higher false positives as compared to the 5 - 15 years age groups (OR = 0.10, P = 0.0006). Parasite prevalence varied between rapid diagnostic tests (RDTs) (40.4%) and microscopy (31.3%) (OR = 0.67, P = 0.2825) with 9.2% discordant RDT false positives. All malaria positive children were Plasmodium falciparum mono-infections. Hospital admissions reduced by 28% between 2005 and 2008, with case fatality rates reducing by 19% between 2006 and2007 inchildren under five years. No marked heterogeneity between LLINs ownership (66%) and utilization (48.3%) was observed (OR = 0.49, P = 0.0978). There was complete (100%) community level knowledge of KO-Tab 1-2-3 LLINs. The study provides evidence of potential of KO-Tab 1-2-3 LLINs for operational scale distribution, and substantiates the need for further longitudinal studies to monitor their insecticidal and physical durability.展开更多
Building indoor dangerous behavior recognition is a specific application in the field of abnormal human recognition.A human dangerous behavior recognition method based on LSTM-GCN with attention mechanism(GLA)model wa...Building indoor dangerous behavior recognition is a specific application in the field of abnormal human recognition.A human dangerous behavior recognition method based on LSTM-GCN with attention mechanism(GLA)model was proposed aiming at the problem that the existing human skeleton-based action recognition methods cannot fully extract the temporal and spatial features.The network connects GCN and LSTMnetwork in series,and inputs the skeleton sequence extracted by GCN that contains spatial information into the LSTM layer for time sequence feature extraction,which fully excavates the temporal and spatial features of the skeleton sequence.Finally,an attention layer is designed to enhance the features of key bone points,and Softmax is used to classify and identify dangerous behaviors.The dangerous behavior datasets are derived from NTU-RGB+D and Kinetics data sets.Experimental results show that the proposed method can effectively identify some dangerous behaviors in the building,and its accuracy is higher than those of other similar methods.展开更多
Long non-coding RNAs(lncRNAs) belong to a large and complex family of RNAs, which play many important roles in regulating gene expression. However, the mechanism underlying the dynamic expression of lncRNAs is still n...Long non-coding RNAs(lncRNAs) belong to a large and complex family of RNAs, which play many important roles in regulating gene expression. However, the mechanism underlying the dynamic expression of lncRNAs is still not very clear. In order to identify lncRNAs and clarify the mechanisms involved, we collected basic information and highlighted the mechanisms underlying lncRNA expression and regulation. Overall, lncRNAs are regulated by several similar transcription factors and protein-coding genes. Epigenetic modification(DNA methylation and histone modification) can also downregulate lncRNA levels in tissues and cells. Moreover, lncRNAs may be degraded or cleaved via interaction with miRNAs and miRNAassociated protein complexes. Furthermore, alternative RNA splicing(AS) may play a significant role in the post-transcriptional regulation of lncRNAs.展开更多
In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rap...In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rapid increase in food consumption, the conflicts of food quality and structure in the supply and demand equilibrium has become more and more obvious and the long-effective mechanism of food security has not been estab-lished yet. It is found that the factors affecting food security in China include the scarcity and dissipation of resources, farmers’ low enthusiasm in planting grain crops and the inappropriateness of the emphasis and measures of macro-economic regulation and control. Therefore, the authors advance to optimize resources allocation, strengthen macro-economic regulation and control and policy stimulation and establish the mechanism of allocating grain production cost, to set up the long-effective mechanism of China food security and keep it stable in the long term.展开更多
文摘Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated bed nets (LLINs), full ownership and optimal use is still limited. In 2021, over a million LLINs were made available for distribution in the South West Region. However, the current situation of malaria has not yet been ascertained following the 2021 mass distribution campaign (MDC). Therefore, the aim of this study was to determine LLIN ownership, coverage, usage and the prevalence of malaria following the 2021 MDC in the Tiko Health District (THD), South West Region of Cameroon. A cross-sectional study was carried from May 1 to 27, 2022 in which a multi-stage sampling technique was used to enroll eligible participants. Data were collected from household heads using questionnaires and capillary blood samples collected from consented household members were used to test for malaria. Data were analyzed using SPSS version 25 at 0.05 significance level. From the 150 households surveyed, 96 (64.0%) owned a mosquito net before the recent MDC. There was an overall significant increase (p p = 0.644) in LLINs ownership between areas where door-to-door (79.5%) and fixed “Hit and Run” (75.8%) strategies were used in the distribution of LLINs in THD. The prevalence of malaria was 10.2%. The regular use of LLINs was significantly associated (p = 0.007) with low malaria prevalence. The 2021 MDC had an impact on malaria prevalence in those who properly used them.
基金the Shanghai Rising-Star Program(No.22QA1403900)the National Natural Science Foundation of China(No.71804106)the Noncarbon Energy Conversion and Utilization Institute under the Shanghai Class IV Peak Disciplinary Development Program.
文摘Accurate load forecasting forms a crucial foundation for implementing household demand response plans andoptimizing load scheduling. When dealing with short-term load data characterized by substantial fluctuations,a single prediction model is hard to capture temporal features effectively, resulting in diminished predictionaccuracy. In this study, a hybrid deep learning framework that integrates attention mechanism, convolution neuralnetwork (CNN), improved chaotic particle swarm optimization (ICPSO), and long short-term memory (LSTM), isproposed for short-term household load forecasting. Firstly, the CNN model is employed to extract features fromthe original data, enhancing the quality of data features. Subsequently, the moving average method is used for datapreprocessing, followed by the application of the LSTM network to predict the processed data. Moreover, the ICPSOalgorithm is introduced to optimize the parameters of LSTM, aimed at boosting the model’s running speed andaccuracy. Finally, the attention mechanism is employed to optimize the output value of LSTM, effectively addressinginformation loss in LSTM induced by lengthy sequences and further elevating prediction accuracy. According tothe numerical analysis, the accuracy and effectiveness of the proposed hybrid model have been verified. It canexplore data features adeptly, achieving superior prediction accuracy compared to other forecasting methods forthe household load exhibiting significant fluctuations across different seasons.
基金Supported by Partly Fund of Guangxi Provincial Health Bureau Scientific Research Project,No.Z2014054Youth Science Foun-dation of Guangxi Medical University,No.GXMUYSF201311+4 种基金Guangxi University Science and Technology Research Projects,No.LX2014075Natural Science Foundation of GuangxiNos.2015GXNSFBA139157,2015GXNSFCA139009National Natural Science Foundation of China,Nos.NSFC81360327,NSFC81560489NSFC81560469
文摘Hepatocellular carcinoma(HCC) is the predominant subject of liver malignancies which arouse global concern. Advanced studies have found that long noncoding RNAs(lnc RNAs) are differentially expressed in HCC and implicate they may play distinct roles in the pathogenesis and metastasis of HCC. However, the underlying mechanisms remain largely unclear. In this review, we summarized the functions and mechanisms of those known aberrantly expressed lncR NAs identified in human HCC tissues. We hope to enlighten more comprehensive researches on the detailed mechanisms of lncR NAs and their application in clinic, such as being used as diagnostic and prognostic biomarkers and the targets for potential therapy. Although studies on lncR NAs in HCC are still deficient, an improved understanding of the roles played by lncR NAs in HCC will lead to a much more effective utilization of those lnc RNAs as novel candidates in early detection, diagnosis, prevention and treatment of HCC.
基金supported by the National Natural Science Foundation of China(41731287,41877279)China Geological Survey Project(DD20160271)
文摘The upper reaches of the Minjiang River are in the eastern margin of the Tibetan Plateau,where active faults are well developed and earthquakes frequently occur.Anomalous climate change and the extremely complex geomechanical properties of rock and soil have resulted in a number of geohazards.Based on the analysis of remote sensing interpretations,geological field surveys,geophysical prospecting and geological dating results,this paper discusses the developmental characteristics of the Gamisi ancient landslide in Songpan County,Sichuan Province,and investigates its geological age and formation mechanism.This study finds that the Gamisi ancient landslide is in the periglacial region of the Minshan Mountain and formed approximately 25 ka BP.The landslide initiation zone has a collapse and slide zone of approximately 22.65×106–31.7×106 m3 and shows a maximum sliding distance of approximately 1.42 km,with an elevation difference of approximately 310 m between the back wall of the landslide and the leading edge of the accumulation area.The landslide movement was characterized by a high speed and long runout.During the sliding process,the landslide body eroded and dammed the ancient Minjiang River valley.The ancient river channel was buried 30-60 m below the surface of the landslide accumulation area.Geophysical prospecting and drilling observations revealed that the ancient riverbed was approximately 80-100 m thick.After the dam broke,the Minjiang River was migrated to the current channel at the leading edge of the landslide.The Gamisi ancient landslide was greatly affected by the regional crustal uplift,topography,geomorphology and paleoclimatic change.The combined action of periglacial karstification and climate change caused the limestone at the rear edge of the landslide fractured,thus providing a lithological foundation for landslide occurrence.Intense tectonic activity along the Minjiang Fault,which runs through the middle and trailing parts of the Gamisi ancient landslide,may have been the main factor inducing landsliding.Studying the Gamisi ancient landslide is of great significance for investigating the regional response to paleoclimatic change and geomorphologic evolution of the Minjiang Fault since the late Pleistocene and for disaster prevention and mitigation.
文摘According to the investigations on the oil and gas pipelines such as the Lan-Cheng-Chong pipeline and the Southwest pipeline, there are two ways of laying pipeline: pipelines paralleling (approximately) to the main slide direction and pipelines perpendicular (approximately) to the main slide direction. If earth-retaining walls have been built for pipelines paralleling to the main slide direction, they will prevent the lands from sliding; On the contrary, without earth-retaining walls, the sharp broken rocks in the backfilling soil will scratch the safeguard of the pipeline when the landslides take place. Pipelines perpendicular to the main slide direction can be classified into four types according to the relative positions between pipelines and landslides: Pipelines over the slide planes, pipelines inside the fracture strips of slide planes, pipelines below the slide planes and pipelines behind the backsides of landslides. The different dynamical mechanisms of the process in which landslide acts against pipelines are analyzed based on whether the pipelines are equipped with fixed frusta, because the sliding resistance depends on whether and how many fixed frusta are equipped and the distance between frusta.
文摘The Eu (2+) and Dy (3+) codoped silicates,Ca_2MgSi_2O_7∶Eu (2+),Dy (3+),was synthesized,and its photoluminescence properties were studied with synchrotron radiation. Under synchrotron radiation excitation at 305 nm,only the characteristic emission from Eu (2+) was excited. But the characteristic emission from Dy (3+) was also found under 175 nm excitation,besides the characteristic emission of Eu (2+). The characteristic emission from Dy (3+) was detected in the Eu (2+) and Dy (3+) codoped long lasting phosphorescence materials,which indicates that Dy (3+) is still existed in the phosphors under continue excitation at 175 nm.
基金Project supported by Technological Key Project of Basic Research of Jilin Province (20020601)
文摘Long lasting phosphorescence (LLP) was observed in Eu2+, Ce3+ co-doped strontium borate glasses prepared under the reducing atmosphere due to the emission of both Eu2 + and Ce3+ . The methods of photoluminescence, thermolu-minescence and phosphorescence were used to study the samples, and possible mechanism was suggested. The co-doping of Ce3 + ions poisoned the phosphorescence emission of Eu2 + because of the competition to obtain the trapped electron . The phosphorescence of Ce3 + in the sample decays more quickly than that of Eu2 + , which is suggested for the reason that the emission energy of Ce3 + is higher or the distance between Ce3 + and electron traps of the glasses is longer.
基金the National Natural Science Foundation of China (10404028)Young Scientists Innovation Foundation of Fujian Province (2007F3027)
文摘As an improvement of reported Y2O2S:Tb^3+, a white-light long-lasting phosphor: Y2O2S:Tb^3+, Sm^3+ was prepared by the solid-state reaction. The photo-luminescence spectra showed that the position and shape of Tb^3+ and Sm^3+ emissions under UV excitation were similar in this host, which ensured a stable white emission color (daylight standard of IEC) under different excitations. The decay curves of co-doped samples indicated that the decay times of emissions of the two ions were close. The thermo-luminescence measurement suggested that the traps created by the doped Sm^3+ ions were helpful to postpone the white afterglow of co-doped samples. Therefore, the function of co-doped Sm^3+ ions was confirmed as improving the white emission colors of samples and acting as new trap centers.
文摘A novel white light emitting long-lasting phosphor Cd1-xDyxSiO3 is reported in this letter. The Dy3+ doped CdSiO3 phosphor emits white light. The phosphorescence can be seen with the naked eye in the dark clearly even after the 254 nm UV irradiation have been removed for about 30 min. In the emission spectrum of 5% Dy3+ doped CdSiO3 phosphor, there are two emission peaks of Dy3+, 580 nm (4F9/26H13/2) and 486 nm (4F9/26H15/2), as well as a broad band emission located at about 410 nm. All the three emissions form a white light with CIE chromaticity coordinates x=0.3874, y=0.3760 and the color temperature is 4000 K under 254 nm excitation. It indicated that this phosphor is a promising new luminescent material for practice application.
文摘Long-lasting phosphor Y2O2S : Eu^3+ , Mg^2+ , Ti^4+ was synthesized by a flux method and their luminescence properties were investigated. The result indicates that the unit cell parameter c is linearly increased with the increase of Eu2O3 content in Y2O2S: Eu^3+ (0.01 ≤ x ≤0.10). On the other hand, the change of unit cell parameter a is not linear dependence. In the Y2O2S: Eu^3 + crystal structure, Eu^3+ ions only replaced Y^3 + ions' places in which it posited center position of c axis. With the increase of Eu2O3 content, the position of the strongest emission peak changed from 540 nm (5D1→^ 7F2 transition) to 626 nm (^5Do→^7TF2 transition), and the maximum intensity was obtained when x = 0.09 in Y2O2S: Eu^3+ (0.01 ≤x ≤0.10). This is due to the environment of trivalent europium in the crystal structure of Y2O2S. Doping with Mg^2+ or Ti^4+. ions alone cannot get the good long-lasting afterglow effect, whereas co-doping with Mg^2 + and Ti^4 + ions and excited with 365 nm ultraviolet light, a strong thermoluminesence peak appeared, red and orange long-lasting phosphorescence (LLP) was also observed and the phosphorescence lasted nearly 3 h in the light perception of the dark-adapted human eye (0.32 mcd·m^-2). Thus the LLP mechanism was analyzed.
基金Project supported by the Young Scientists' Innovation Foundation of Fujian Province (2007F3027)the Natural Science Foundation of Fujian Province of China (A0510014)+2 种基金the Science Foundation of the Department of Science and Technology of Fujian Province of China (2006F5025)the Science Foundation of the Educational Department of Fujian Province of China (JB08063)the Special Science Foundation for Key Research of Fujian Province (2007HJ0004-2)
文摘A white long-lasting phosphor Ca2MgSi2O7:Dy3+ was prepared by the solid-state reaction. A strong band peaked at 260 nm was shown in the excitation spectrum of 578 nm emission, which might be attributed to the oxygen deficiency of the host. After irradiated with 254 nm for 4 min, the white afterglow of the sample could be seen for 3 h. Moreover, the depths and frequency factors of trap centers were calculated from the thermo-luminescence curve of the sample, which indicated that the trap centers corresponding to the 414 K band were more helpful to the long-lasting phosphorescence.
基金supported by the Fundamental Research Foundation of Engineering Research Institute of University of Science and Technology Beijing (No2009-006)
文摘A novel red long-lasting phosphor, (YxGd1-x)2O3:Eu3+, Sm3+, Si4+, Mg2+, was synthesized by the co-precipitation method using oxalate precipitation as the precursor. X-ray diffraction (XRD), scanning electronic microscopy (SEM), integrated thermal analyzer (TG), and photoluminescence spectra (PL) as well as the ST-900PM weak light photometer were used to study the synthesis conditions, morphology, luminescence properties, and the decay time of the phosphor. The XRD results show that the products synthesized at 1400~C for 4 h have good crystallization without any detectable impurity phases. Based on the PL spectra, the optimal conditions are as the following. The molar ratios of Y3+ to Gd3+ and Eu3+ to Sm3+ are 2:8 and 3:1, respectively, and the contents of Mg2+ and SiO2 are 5mol% and 3mol%, respectively. The decay time monitored by the ST-900PM weak light photometer is 7200 s, increasing 44% and 100%, respectively, compared with the Eu3+ and Sm3+ single-doped phosphors. The results indicate that the energy transfer is from Sm3+ to Eu3+ ion, and Sm3+ is a good sensitizer to Eu3+.
基金Funded by the Project-sponsored by SRF for ROCS,SEM
文摘Long lasting phosphorescence (LLP) and photo-stimulated long lasting phosphorescence (PSLLP) were observed in Tb^3+-doped strontium borosilicate glasses. The green phosphorescence arises fromf-f transitions of Tb^3+ and can be observed with naked eyes in the dark for up to 10 hours after the irradiation with a UV lamp (λmax =254 nm) for 30 min at room temperature. The glass could re-emit LLP under the stimulation of a UV lamp (λmax=366 rim) for 60 seconds after the LLP disappeared. The re-emitted LLP is called PSLLP. The glass sample was characterized by the fluorescence and thermoluminescence spectra, respectively. The possible mechanism of the LLP and PSLLP was also discussed.
基金Funded by the State Key Project of Basic Research of China(No.GB1998061312)
文摘Mn^2+ doped ZnO-P2O5 glasses emit red fluorescence, which shows that Mn^2+ ion doped in zinc phosphate glass is octahedrally coordinated. Moreover, glass samples exhibit bright red long lasting phosphorescence (LLP) when the mole percent of ZnO are more than 60%. After turnoff the irradiation source of UV lamp peaking at 254 nm, the red phosphorescence can be observed for about 6 h in the limit of light perception for naked eyes (0.32 mcd/m^2). Photoluminescence (PL) spectra, LLP emission spectra and decay curves were detected. Increasing MnO or ZnO content, the phosphorescence intensity can be improved distinctly and the emission wavelength can be also adjusted from 595 nm to 628 nm. According to the structural characteristic of zinc phosphates glasses, we suggest that non-bridge oxygen (NBO) is probably related with the arising of LLE Meantime, the variation of crystal field intensity induced that the LLP emission wavelength red shifts.
文摘A correct and timely fault diagnosis is important for improving the safety and reliability of chemical processes. With the advancement of big data technology, data-driven fault diagnosis methods are being extensively used and still have considerable potential. In recent years, methods based on deep neural networks have made significant breakthroughs, and fault diagnosis methods for industrial processes based on deep learning have attracted considerable research attention. Therefore, we propose a fusion deeplearning algorithm based on a fully convolutional neural network(FCN) to extract features and build models to correctly diagnose all types of faults. We use long short-term memory(LSTM) units to expand our proposed FCN so that our proposed deep learning model can better extract the time-domain features of chemical process data. We also introduce the attention mechanism into the model, aimed at highlighting the importance of features, which is significant for the fault diagnosis of chemical processes with many features. When applied to the benchmark Tennessee Eastman process, our proposed model exhibits impressive performance, demonstrating the effectiveness of the attention-based LSTM FCN in chemical process fault diagnosis.
文摘Insecticide treated nets (ITNs) play a pivotal role in the prevention and control of malaria. Conversely, inadequate levels of ownership, utilization and durability invariably compromise their efficacy. Operational performance of the KO-Tab 1-2-3 Long Lasting Insecticidal Nets (LLINs) was assessed using the World Health Organization (WHO) standard entomological and epidemiological procedures, and a pretested structured questionnaire. The median knock down time for Anopheles funestus s.l. was 30 minutes (95% CI 26.3 - 34.0). Post exposure mean mortality rates were 34% at one hour and 80.0% at 24 hours (OR = 0.13, P = 0.00002). Children between the ages of 1 - 4 years old exhibited higher false positives as compared to the 5 - 15 years age groups (OR = 0.10, P = 0.0006). Parasite prevalence varied between rapid diagnostic tests (RDTs) (40.4%) and microscopy (31.3%) (OR = 0.67, P = 0.2825) with 9.2% discordant RDT false positives. All malaria positive children were Plasmodium falciparum mono-infections. Hospital admissions reduced by 28% between 2005 and 2008, with case fatality rates reducing by 19% between 2006 and2007 inchildren under five years. No marked heterogeneity between LLINs ownership (66%) and utilization (48.3%) was observed (OR = 0.49, P = 0.0978). There was complete (100%) community level knowledge of KO-Tab 1-2-3 LLINs. The study provides evidence of potential of KO-Tab 1-2-3 LLINs for operational scale distribution, and substantiates the need for further longitudinal studies to monitor their insecticidal and physical durability.
文摘Building indoor dangerous behavior recognition is a specific application in the field of abnormal human recognition.A human dangerous behavior recognition method based on LSTM-GCN with attention mechanism(GLA)model was proposed aiming at the problem that the existing human skeleton-based action recognition methods cannot fully extract the temporal and spatial features.The network connects GCN and LSTMnetwork in series,and inputs the skeleton sequence extracted by GCN that contains spatial information into the LSTM layer for time sequence feature extraction,which fully excavates the temporal and spatial features of the skeleton sequence.Finally,an attention layer is designed to enhance the features of key bone points,and Softmax is used to classify and identify dangerous behaviors.The dangerous behavior datasets are derived from NTU-RGB+D and Kinetics data sets.Experimental results show that the proposed method can effectively identify some dangerous behaviors in the building,and its accuracy is higher than those of other similar methods.
文摘Long non-coding RNAs(lncRNAs) belong to a large and complex family of RNAs, which play many important roles in regulating gene expression. However, the mechanism underlying the dynamic expression of lncRNAs is still not very clear. In order to identify lncRNAs and clarify the mechanisms involved, we collected basic information and highlighted the mechanisms underlying lncRNA expression and regulation. Overall, lncRNAs are regulated by several similar transcription factors and protein-coding genes. Epigenetic modification(DNA methylation and histone modification) can also downregulate lncRNA levels in tissues and cells. Moreover, lncRNAs may be degraded or cleaved via interaction with miRNAs and miRNAassociated protein complexes. Furthermore, alternative RNA splicing(AS) may play a significant role in the post-transcriptional regulation of lncRNAs.
文摘In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rapid increase in food consumption, the conflicts of food quality and structure in the supply and demand equilibrium has become more and more obvious and the long-effective mechanism of food security has not been estab-lished yet. It is found that the factors affecting food security in China include the scarcity and dissipation of resources, farmers’ low enthusiasm in planting grain crops and the inappropriateness of the emphasis and measures of macro-economic regulation and control. Therefore, the authors advance to optimize resources allocation, strengthen macro-economic regulation and control and policy stimulation and establish the mechanism of allocating grain production cost, to set up the long-effective mechanism of China food security and keep it stable in the long term.