AIM: To analyze possible relationships between CA ⅠⅩ/CA Ⅻ and pVHL expression in normal and neoplastic colorectal mucosa.METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients...AIM: To analyze possible relationships between CA ⅠⅩ/CA Ⅻ and pVHL expression in normal and neoplastic colorectal mucosa.METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients was performed to evaluate the distribution and semi-quantitatively assess the levels of CA ⅠⅩ, CA Ⅻ and pVHL. VHL mRNAs from 14 fresh-frozen tumors was amplified by RT-PCR and subjected to sequencing. CA9 and CA12 mRNA levels were analyzed by semi-quantitative RT-PCR in comparison with VEGFas an indicator of hypoxia that uncouples the pVHL control.RESULTS: Tumor tissues were associated with a borderline increase of CA ⅠⅩ staining signal and slight but significant decrease of CA Ⅻ immunoreactivity, whereas no association was found for pVHL. Sequence analysis of RT-PCR-amplified VHL mRNAs revealed no deletions/mutations, suggesting that they were VHL-competent. We did not observe any correlation between pVHL and CA ⅠⅩ/CA Ⅻ proteins as well as between VEGF and CA9 mRNAs, but the tumor-associated changes in mRNA levels of VEGF and CA12 showed a significant inverse relationship.CONCLUSION: Our results indicate that CA9 and CA12 are regulated by different intratumoral factors and that lack of apparent relationship between the levels of CA ⅠⅩ/CA Ⅻ and pVHL cannot be fully assigned to uncoupling of negative regulatory function of pVHL by tumor hypoxia signified by induced VEGF transcription. The interplay between the functional pVHL and CA ⅠⅩ/CA Ⅻ in colorectal tumors seems rather complex and is not evident merely at the expression levels.展开更多
Spatial and temporal informationon urban infrastructure is essential and requires various land-cover/land-use planning and management applications.Besides,a change in infrastructure has a direct impact on other land-c...Spatial and temporal informationon urban infrastructure is essential and requires various land-cover/land-use planning and management applications.Besides,a change in infrastructure has a direct impact on other land-cover and climatic conditions.This study assessed changes in the rate and spatial distribution of Peshawar district’s infrastructure and its effects on Land Surface Temperature(LST)during the years 1996 and 2019.For this purpose,firstly,satellite images of bands7 and 8 ETM+(Enhanced Thematic Mapper)plus and OLI(Operational Land Imager)of 30 m resolution were taken.Secondly,for classification and image processing,remote sensing(RS)applications ENVI(Environment for Visualising Images)and GIS(Geographic Information System)were used.Thirdly,for better visualization and more in-depth analysis of land sat images,pre-processing techniques were employed.For Land use and Land cover(LU/LC)four types of land cover areas were identified-vegetation area,water cover,urbanized area,and infertile land for the years under research.The composition of red,green,and near infra-red bands was used for supervised classification.Classified images were extracted for analyzing the relative infrastructure change.A comparative analysis for the classification of images is performed for SVM(Support Vector Machine)and ANN(Artificial Neural Network).Based on analyzing these images,the result shows the rise in the average temperature from 30.04℃ to 45.25℃.This only possible reason is the increase in the built-up area from 78.73 to 332.78 Area km^(2) from 1996 to 2019.It has also been witnessed that the city’s sides are hotter than the city’s center due to the barren land on the borders.展开更多
AIM To investigate expression of four alpha-carbonic anhydrases(CAs) in colorectal carcinomas(CRC) and compare the results with patients' survival.METHODS Colorectal carcinoma samples from 539 CRC patients and con...AIM To investigate expression of four alpha-carbonic anhydrases(CAs) in colorectal carcinomas(CRC) and compare the results with patients' survival.METHODS Colorectal carcinoma samples from 539 CRC patients and control tissues were arranged as tissue microarrays and analyzed with antibodies against CA Ⅱ, CA Ⅶ, CA Ⅸ, and CA Ⅻ. Intensity and extent of staining were both scored from 0 to 3 in each sample. These enzyme expression levels were then correlated to patients' survival and clinicopathological parameters, which were tumor differentiation grade and stage, site of tumor, patients' age, and gender. Kaplan-Meier analysis and Cox regression hazard ratio model were used to analyze survival data. RESULTS CA Ⅱ and CA Ⅻ staining intensities correlated with patients' survival in that higher expression indicated poorer prognosis. In Cox regression analysis one unit increase in the CA Ⅱ intensity increased the hazard ratio to 1.19 fold(CI: 1.04-1.37, P = 0.009). A significant correlation was also found when comparing CA Ⅻ staining intensity with survival of CRC patients(HR = 1.18, 95%CI: 1.01-1.38, P = 0.036). The extent of CA Ⅻ immunostaining did not correlate to the patients' survival(P = 0.242, Kaplan-Meier analysis). A significant interaction between age group and extent of the CA Ⅱ staining was found. Increased extent of CA Ⅱ had a significant hazard ratio among patients 65 years and older(1.42, 95%CI: 1.16-1.73, P = 0.0006). No correlations were found between CA Ⅶ(intensity P = 0.566, extent P = 0.495, Kaplan-Meier analysis), or CA Ⅸ(intensity P = 0.879, extent P = 0.315, KaplanMeier analysis) immunostaining results and survival, or the other parameters. CONCLUSION The present findings indicate that CA Ⅱ and CA Ⅻ could be useful in predicting survival in CRC.展开更多
Satellite networks have high requirements for security and data processing speed.In order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set...Satellite networks have high requirements for security and data processing speed.In order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set in the network.Due to the characteristics of global perspective,control data separation,and centralized control of SDN,the idea of SDN is introduced to the design of the satellite network model.As a result,satellite nodes are only responsible for data transmission,while the maintenance of the links and the calculation of routes are implemented by the controller.For the massive LEO satellite network based on SDN,a state evaluation decision routing mechanism is proposed.The designed mechanism monitors the status of the entire network effectively and reduces the on-board load on the satellite network.The best routing decision is made under the comprehensive consideration of the current and historical status of each inter-satellite link between Low Earth Orbit(LEO)satellite network nodes.The calculation and storage requirements are controlled within a reasonable range.Based on the curve parameter transmission fuzzy encryption algorithm,a safe and reliable condition assessment decision routing mechanism(CADRM)is designed.It ensures that the personal information of the LEO satellite network can be transmitted safely and effectively.The experimental simulation results show the improvement of network throughput,the reduction of packet loss rate and the enhancing of network reliability.展开更多
BACKGROUND Acute epiploic appendagitis of the appendix (AEAA) is a rare self-limiting inflammatory disorder of the epiploic appendages (EA) close to the vermiform appendix, which often times mimicking the presentation...BACKGROUND Acute epiploic appendagitis of the appendix (AEAA) is a rare self-limiting inflammatory disorder of the epiploic appendages (EA) close to the vermiform appendix, which often times mimicking the presentation of acute appendicitis (AA). To date, very few cases of AEAA have been reported. We report a case of a 52-year old man with the clinical suspicion of AA, but post-operative specimen examination confirmed AEAA as the final diagnosis. CASE SUMMARY A 52-year-old morbidly obese man presented to the emergency department with a 1-d history of the right lower quadrant (RLQ) abdominal pain. Physical examination revealed localized RLQ tenderness mimicking AA. The computed tomography abdomen was inconclusive, and a decision was made to perform laparoscopic appendectomy (LA). During the LA, an infarcted epiploic appendage at the tip of appendix and adherent to the abdominal wall was found, which was entirely excised. Final pathology showed congested and hemorrhagic epiploic appendage without any accompanied acute inflammatory changes in the wall of the appendix. Postoperative course was uneventful and he was doing well at seven months follow-up. CONCLUSION The possibility of AEAA should be considered in patients clinically suspected of having AA. Surgery is considered for those refractory to conservative management, with inconclusive diagnosis or develop complications at presentation.展开更多
Verifiable secret sharing mainly solves the cheating behavior between malicious participants and the ground control center in the satellite network.The verification stage can verify the effectiveness of secret shares ...Verifiable secret sharing mainly solves the cheating behavior between malicious participants and the ground control center in the satellite network.The verification stage can verify the effectiveness of secret shares issued by the ground control center to each participant and verify the effectiveness of secret shares shown by participants.We use a lot of difficult assumptions based on mathematical problems in the verification stage,such as solving the difficult problem of the discrete logarithm,large integer prime factorization,and so on.Compared with other verifiable secret sharing schemes designed for difficult problems under the same security,the verifiable secret sharing scheme based on the Elliptic Curve Cryptography(ECC)system has the advantages of less computational overhead and shorter key.At present,the binary polynomial is a single secret scheme and cannot provide effective verification.Therefore,based on a Protected Verifiable Synchronous Multi Secret Sharing(PVS-MSS)scheme,this paper is designed based on bivariate asymmetric polynomials.The advanced verifiable attribute is introduced into the Protected Secret Sharing(PSS)scheme.This paper extends the protected synchronous multi-secret sharing scheme based on bivariate polynomial design.The ECC system constructs the security channel between the ground control center and participants and constructs the verification algorithm.Through the verification algorithm,any participant can verify the consistency and effectiveness of the secret shadow and secret share received from other participants or presented by the secret distribution center.Therefore,no additional key agreement protocol is required;participants do not need to negotiate the session key for encryption;the secret share polynomial can generate the session key between participants and speed up the secret reconstruction process.The verification stage has lower computational complexity than the verifiable scheme constructed by Rivest Shamir Adleman (RSA) and other encryption methods. Chinese Remainder Theorem (CRT)is used to update the secret shadow. The secret shadow does not need to beupdated with the change of the scheme shared secret, and the public valueupdate efficiency is higher. Reduce the complexity of sharing secret updatesin a synchronous multi-secret sharing scheme.展开更多
Under the background of“Internet plus”rapid development,the agricultural logistics industry should apply information technology to every link of the agricultural product logistics industry chain.By making full use o...Under the background of“Internet plus”rapid development,the agricultural logistics industry should apply information technology to every link of the agricultural product logistics industry chain.By making full use of the decision making module of the agricultural logistics information system,we can realize the full sharing of information and data resources,which makes the decision-making scheme of the agricultural logistics information system more optimized.In real economic society,the uncertainty and mismatch between the customer’s logistics service demand and the logistics service capability that the logistics service function provider can provide,that is,when the two information are asymmetric,how to use the third-party contract to coordinate the income and profit distribution of the two,to make the information system decision making more reasonable?This paper mainly studies the coordination scheme of agricultural logistics information system decision making under uncertain output and demand information by introducing the spot market.A joint coordination strategy based on revenue sharing and penalty feedback contracts proposes decentralized decision making based on game theory.Experiments show that the flexible ordering strategy proposed in this paper can reduce the logistics service supply chain’s uncertainty and significantly improve the logistics service supply chain’s overall income level through coordination contracts.展开更多
Congestion control is one of the main obstacles in cyberspace traffic.Overcrowding in internet traffic may cause several problems;such as high packet hold-up,high packet dropping,and low packet output.In the course of...Congestion control is one of the main obstacles in cyberspace traffic.Overcrowding in internet traffic may cause several problems;such as high packet hold-up,high packet dropping,and low packet output.In the course of data transmission for various applications in the Internet of things,such problems are usually generated relative to the input.To tackle such problems,this paper presents an analytical model using an optimized Random Early Detection(RED)algorithm-based approach for internet traffic management.The validity of the proposed model is checked through extensive simulation-based experiments.An analysis is observed for different functions on internet traffic.Four performance metrics are taken into consideration,namely,the possibility of packet loss,throughput,mean queue length and mean queue delay.Three sets of experiments are observed with varying simulation results.The experiments are thoroughly analyzed and the best packet dropping operation with minimum packet loss is identified using the proposed model.展开更多
Spatial diversity plays a significant role in wireless communication systems,including the Fourth Generation(4G)and Fifth Generation(5G)systems,and it is expected to be a fundamental part of the future wireless commun...Spatial diversity plays a significant role in wireless communication systems,including the Fourth Generation(4G)and Fifth Generation(5G)systems,and it is expected to be a fundamental part of the future wireless communication systems as well.The Multiple-Input Multiple-Output(MIMO)technology,which is included in the IEEE 802.16j standard,still holds the most crucial position in the 4G spectrum as it promises to improve the throughput,capacity,spectral,and energy efficiency of wireless communication systems in the 2020s.This makes MIMO a viable technology for delay constrained medical and health care facilities.This paper presents an approximate closed-form expression of the ergodic capacity for the Decode-and-Forward(DF)protocol MIMO-Orthogonal Frequency Division Multiplexing(OFDM)relaying network.Although MIMO-OFDM is highly valuable for modern high-speed wireless communication systems,especially in the medical sciences,its performance degrades in multi-hop relay networks.Therefore,in this paper,an approximate closed-form expression is derived for an end-to-end ergodic capacity of multi-hop DF MIMO-OFDM wireless communication system has been presented.Monte-Carlo simulations are conducted to verify the performance of the presented analysis regarding the capacity(bits/s/Hz)for different SNR-dB values for single,2×2,4×4,and multi-hop DF MIMOOFDM systems.The presented results provide useful insights for the research on the end-to-end ergodic capacity evaluation.展开更多
The next-generation wireless networks are expected to provide higher capacity,system throughput with improved energy efficiency.One of the key technologies,to meet the demand for high-rate transmission,is deviceto-dev...The next-generation wireless networks are expected to provide higher capacity,system throughput with improved energy efficiency.One of the key technologies,to meet the demand for high-rate transmission,is deviceto-device(D2D)communication which allows users who are close to communicating directly instead of transiting through base stations,and D2D communication users to share the cellular user chain under the control of the cellular network.As a new generation of cellular network technology,D2D communication technology has the advantages of improving spectrum resource utilization and improving system throughput and has become one of the key technologies that have been widely concerned in the industry.However,due to the sharing of cellular network resources,D2D communication causes severe interference to existing cellular systems.One of the most important factors in D2D communication is the spectrum resources utilization and energy consumption which needs considerable attention from research scholars.To address these issues,this paper proposes an efficient algorithm based on the idea of particle swarm optimization.The main idea is to maximize the energy efficiency based on the overall link optimization of D2D user pairs by generating an allocation matrix of spectrum and power.The D2D users are enabled to reuse multiple cellular user’s resources by enhancing their total energy efficiency based on the quality of service constraints and the modification of location and speed in particle swarm.Such constraint also provides feasibility to solve the original fractional programming problem.Simulation results indicate that the proposed scheme effectively improved the energy efficiency and spectrum utilization as compared with other competing alternatives.展开更多
Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical properties.In this study,we designed and fabricated three novel membranes with different act...Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical properties.In this study,we designed and fabricated three novel membranes with different active layers using the crosslinkers:terephthaloyl chloride,isophthaloyl chloride,and trimesoyl chloride.The crosslinkers were reacted with an aqueous solution of an aliphatic tetra-amine.Because these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization,the resultant membranes also possess different structural properties.The water contact angle of the fabricated membranes also varies;the water contact angles of 4A-3P-TPC@PSF/PET,4A-3P-TMC@PSF/PET,and 4A-3P-IPC@PSF/PET,are 68.9°,65.6°,and 53.9°,respectively.Similarly,the desalination performance of resultant membranes also showed variations,with 4A-3P-TPC@PSF/PET,4A-3P-IPC@PSF/PET,and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14,25.70,and 30.90 L·m^(−2)·h^(−1),respectively,at 2.5 MPa.The 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine,and cationic dye rhodamine B,MgCl_(2),and amitriptyline rejection rates of 98.6%,92.7%and 80.9%,respectively.The 4A-3P-TMC@PSF/PET membrane showed mediocre performance,while 4A-3P-IPC@PSF/PET membrane showed even lower performance,with a 35%rejection of methyl orange dye.展开更多
Background The neutron activation analysis(NAA)is a very powerful method for multi-element analysis of samples.NAA technique needs to be developed for low neutron flux in millicuries using the 241Am-Be neutron source....Background The neutron activation analysis(NAA)is a very powerful method for multi-element analysis of samples.NAA technique needs to be developed for low neutron flux in millicuries using the 241Am-Be neutron source.Aims To optimize sample and neutron source geometry for maximumγ-ray yield for neutron activation analysis.Method Gamma ray neutron activation analysis(NAA)has been set up where a 50-millicurie Am-Be neutron source is available.In this experimental setup,the neutron source is placed at the center of a cylindrical water tank of 40 x 40 cm in xyz plan,and thermal neutrons are produced at a distance of 1.2 cm from the source.The system is used for the activation analysis of sodium carbonate,sodium chloride and copper with the gamma ray emissions of 1.37,1.73,2.25 and 2.76 MeV for 24Na and 0.511 MeV for 64Cu having half lives of 15 hrs and 12.9 hrs,respectively.The thermal neutron activation analysis has been demonstrated by placing the samples at about 1.2 cm from the neutron source.HPGe and 3x3 inch NaI(Tl)gamma ray spectrometers have been used for the gamma ray spectrometry of these activated samples with the use of a Marinelli beaker.The geometry of the sample with respect to the neutron source has been optimized for the maximumγ-ray yield in NAA.Conclusion The geometry of the sample with respect to the neutron source has been optimized for the maximumγ-ray yield in NAA.The increase in gamma ray flux distribution in the medium of water,due to the neutron source inside the tank,has been observed by a GM detector which is due to the production of short-lived 16N on activation of 16O in water.This system can also be used for promptγ-ray analysis.展开更多
基金Supported by the Grants From Sigrid Juselius Foundation, from Finnish Cultural Foundation and Finnish Dental Society from the National Institutes of Health (DK40163, GM34182, and GM53405)from Slovak Grant Agency (2/2025) from the Slovak Government (Cancer Genomics SP 51/0280800) and from Bayer Corporation
文摘AIM: To analyze possible relationships between CA ⅠⅩ/CA Ⅻ and pVHL expression in normal and neoplastic colorectal mucosa.METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients was performed to evaluate the distribution and semi-quantitatively assess the levels of CA ⅠⅩ, CA Ⅻ and pVHL. VHL mRNAs from 14 fresh-frozen tumors was amplified by RT-PCR and subjected to sequencing. CA9 and CA12 mRNA levels were analyzed by semi-quantitative RT-PCR in comparison with VEGFas an indicator of hypoxia that uncouples the pVHL control.RESULTS: Tumor tissues were associated with a borderline increase of CA ⅠⅩ staining signal and slight but significant decrease of CA Ⅻ immunoreactivity, whereas no association was found for pVHL. Sequence analysis of RT-PCR-amplified VHL mRNAs revealed no deletions/mutations, suggesting that they were VHL-competent. We did not observe any correlation between pVHL and CA ⅠⅩ/CA Ⅻ proteins as well as between VEGF and CA9 mRNAs, but the tumor-associated changes in mRNA levels of VEGF and CA12 showed a significant inverse relationship.CONCLUSION: Our results indicate that CA9 and CA12 are regulated by different intratumoral factors and that lack of apparent relationship between the levels of CA ⅠⅩ/CA Ⅻ and pVHL cannot be fully assigned to uncoupling of negative regulatory function of pVHL by tumor hypoxia signified by induced VEGF transcription. The interplay between the functional pVHL and CA ⅠⅩ/CA Ⅻ in colorectal tumors seems rather complex and is not evident merely at the expression levels.
文摘Spatial and temporal informationon urban infrastructure is essential and requires various land-cover/land-use planning and management applications.Besides,a change in infrastructure has a direct impact on other land-cover and climatic conditions.This study assessed changes in the rate and spatial distribution of Peshawar district’s infrastructure and its effects on Land Surface Temperature(LST)during the years 1996 and 2019.For this purpose,firstly,satellite images of bands7 and 8 ETM+(Enhanced Thematic Mapper)plus and OLI(Operational Land Imager)of 30 m resolution were taken.Secondly,for classification and image processing,remote sensing(RS)applications ENVI(Environment for Visualising Images)and GIS(Geographic Information System)were used.Thirdly,for better visualization and more in-depth analysis of land sat images,pre-processing techniques were employed.For Land use and Land cover(LU/LC)four types of land cover areas were identified-vegetation area,water cover,urbanized area,and infertile land for the years under research.The composition of red,green,and near infra-red bands was used for supervised classification.Classified images were extracted for analyzing the relative infrastructure change.A comparative analysis for the classification of images is performed for SVM(Support Vector Machine)and ANN(Artificial Neural Network).Based on analyzing these images,the result shows the rise in the average temperature from 30.04℃ to 45.25℃.This only possible reason is the increase in the built-up area from 78.73 to 332.78 Area km^(2) from 1996 to 2019.It has also been witnessed that the city’s sides are hotter than the city’s center due to the barren land on the borders.
基金Supported by the Sigrid Jusélius Foundation,the Academy of Finland,the Medical Research Funds of Tampere University Hospital and Helsinki University Hospital,and Jane and Aatos Erkko Foundation
文摘AIM To investigate expression of four alpha-carbonic anhydrases(CAs) in colorectal carcinomas(CRC) and compare the results with patients' survival.METHODS Colorectal carcinoma samples from 539 CRC patients and control tissues were arranged as tissue microarrays and analyzed with antibodies against CA Ⅱ, CA Ⅶ, CA Ⅸ, and CA Ⅻ. Intensity and extent of staining were both scored from 0 to 3 in each sample. These enzyme expression levels were then correlated to patients' survival and clinicopathological parameters, which were tumor differentiation grade and stage, site of tumor, patients' age, and gender. Kaplan-Meier analysis and Cox regression hazard ratio model were used to analyze survival data. RESULTS CA Ⅱ and CA Ⅻ staining intensities correlated with patients' survival in that higher expression indicated poorer prognosis. In Cox regression analysis one unit increase in the CA Ⅱ intensity increased the hazard ratio to 1.19 fold(CI: 1.04-1.37, P = 0.009). A significant correlation was also found when comparing CA Ⅻ staining intensity with survival of CRC patients(HR = 1.18, 95%CI: 1.01-1.38, P = 0.036). The extent of CA Ⅻ immunostaining did not correlate to the patients' survival(P = 0.242, Kaplan-Meier analysis). A significant interaction between age group and extent of the CA Ⅱ staining was found. Increased extent of CA Ⅱ had a significant hazard ratio among patients 65 years and older(1.42, 95%CI: 1.16-1.73, P = 0.0006). No correlations were found between CA Ⅶ(intensity P = 0.566, extent P = 0.495, Kaplan-Meier analysis), or CA Ⅸ(intensity P = 0.879, extent P = 0.315, KaplanMeier analysis) immunostaining results and survival, or the other parameters. CONCLUSION The present findings indicate that CA Ⅱ and CA Ⅻ could be useful in predicting survival in CRC.
基金This work is supported by Fundamental Research Funds for the Central Universities of China(328201911),C.G.(Chao Guo)the Open Project Program of National Engineering Laboratory for Agri-product Quality Traceability,C.G.(Chao Guo),Beijing Technology and Business University(BTBU)No.AQT-2018Y-B4,C.G.(Chao Guo)Higher Education Department of the Ministry of Education Industry-university Cooperative Education Project,C.G.(Chao Guo),and Education and Teaching Reform Project of Beijing Electronic and Technology Institute,C.G.(Chao Guo).
文摘Satellite networks have high requirements for security and data processing speed.In order to improve the reliability of the network,software-defined network(SDN)technology is introduced and a central controller is set in the network.Due to the characteristics of global perspective,control data separation,and centralized control of SDN,the idea of SDN is introduced to the design of the satellite network model.As a result,satellite nodes are only responsible for data transmission,while the maintenance of the links and the calculation of routes are implemented by the controller.For the massive LEO satellite network based on SDN,a state evaluation decision routing mechanism is proposed.The designed mechanism monitors the status of the entire network effectively and reduces the on-board load on the satellite network.The best routing decision is made under the comprehensive consideration of the current and historical status of each inter-satellite link between Low Earth Orbit(LEO)satellite network nodes.The calculation and storage requirements are controlled within a reasonable range.Based on the curve parameter transmission fuzzy encryption algorithm,a safe and reliable condition assessment decision routing mechanism(CADRM)is designed.It ensures that the personal information of the LEO satellite network can be transmitted safely and effectively.The experimental simulation results show the improvement of network throughput,the reduction of packet loss rate and the enhancing of network reliability.
文摘BACKGROUND Acute epiploic appendagitis of the appendix (AEAA) is a rare self-limiting inflammatory disorder of the epiploic appendages (EA) close to the vermiform appendix, which often times mimicking the presentation of acute appendicitis (AA). To date, very few cases of AEAA have been reported. We report a case of a 52-year old man with the clinical suspicion of AA, but post-operative specimen examination confirmed AEAA as the final diagnosis. CASE SUMMARY A 52-year-old morbidly obese man presented to the emergency department with a 1-d history of the right lower quadrant (RLQ) abdominal pain. Physical examination revealed localized RLQ tenderness mimicking AA. The computed tomography abdomen was inconclusive, and a decision was made to perform laparoscopic appendectomy (LA). During the LA, an infarcted epiploic appendage at the tip of appendix and adherent to the abdominal wall was found, which was entirely excised. Final pathology showed congested and hemorrhagic epiploic appendage without any accompanied acute inflammatory changes in the wall of the appendix. Postoperative course was uneventful and he was doing well at seven months follow-up. CONCLUSION The possibility of AEAA should be considered in patients clinically suspected of having AA. Surgery is considered for those refractory to conservative management, with inconclusive diagnosis or develop complications at presentation.
基金This work is supported by The State Key Laboratory of Integrated Services Networks,Xidian University(ISN22-13).
文摘Verifiable secret sharing mainly solves the cheating behavior between malicious participants and the ground control center in the satellite network.The verification stage can verify the effectiveness of secret shares issued by the ground control center to each participant and verify the effectiveness of secret shares shown by participants.We use a lot of difficult assumptions based on mathematical problems in the verification stage,such as solving the difficult problem of the discrete logarithm,large integer prime factorization,and so on.Compared with other verifiable secret sharing schemes designed for difficult problems under the same security,the verifiable secret sharing scheme based on the Elliptic Curve Cryptography(ECC)system has the advantages of less computational overhead and shorter key.At present,the binary polynomial is a single secret scheme and cannot provide effective verification.Therefore,based on a Protected Verifiable Synchronous Multi Secret Sharing(PVS-MSS)scheme,this paper is designed based on bivariate asymmetric polynomials.The advanced verifiable attribute is introduced into the Protected Secret Sharing(PSS)scheme.This paper extends the protected synchronous multi-secret sharing scheme based on bivariate polynomial design.The ECC system constructs the security channel between the ground control center and participants and constructs the verification algorithm.Through the verification algorithm,any participant can verify the consistency and effectiveness of the secret shadow and secret share received from other participants or presented by the secret distribution center.Therefore,no additional key agreement protocol is required;participants do not need to negotiate the session key for encryption;the secret share polynomial can generate the session key between participants and speed up the secret reconstruction process.The verification stage has lower computational complexity than the verifiable scheme constructed by Rivest Shamir Adleman (RSA) and other encryption methods. Chinese Remainder Theorem (CRT)is used to update the secret shadow. The secret shadow does not need to beupdated with the change of the scheme shared secret, and the public valueupdate efficiency is higher. Reduce the complexity of sharing secret updatesin a synchronous multi-secret sharing scheme.
基金The Agricultural Science and Technology Innovation Program(ASTIP-IAED-2021-08).
文摘Under the background of“Internet plus”rapid development,the agricultural logistics industry should apply information technology to every link of the agricultural product logistics industry chain.By making full use of the decision making module of the agricultural logistics information system,we can realize the full sharing of information and data resources,which makes the decision-making scheme of the agricultural logistics information system more optimized.In real economic society,the uncertainty and mismatch between the customer’s logistics service demand and the logistics service capability that the logistics service function provider can provide,that is,when the two information are asymmetric,how to use the third-party contract to coordinate the income and profit distribution of the two,to make the information system decision making more reasonable?This paper mainly studies the coordination scheme of agricultural logistics information system decision making under uncertain output and demand information by introducing the spot market.A joint coordination strategy based on revenue sharing and penalty feedback contracts proposes decentralized decision making based on game theory.Experiments show that the flexible ordering strategy proposed in this paper can reduce the logistics service supply chain’s uncertainty and significantly improve the logistics service supply chain’s overall income level through coordination contracts.
文摘Congestion control is one of the main obstacles in cyberspace traffic.Overcrowding in internet traffic may cause several problems;such as high packet hold-up,high packet dropping,and low packet output.In the course of data transmission for various applications in the Internet of things,such problems are usually generated relative to the input.To tackle such problems,this paper presents an analytical model using an optimized Random Early Detection(RED)algorithm-based approach for internet traffic management.The validity of the proposed model is checked through extensive simulation-based experiments.An analysis is observed for different functions on internet traffic.Four performance metrics are taken into consideration,namely,the possibility of packet loss,throughput,mean queue length and mean queue delay.Three sets of experiments are observed with varying simulation results.The experiments are thoroughly analyzed and the best packet dropping operation with minimum packet loss is identified using the proposed model.
文摘Spatial diversity plays a significant role in wireless communication systems,including the Fourth Generation(4G)and Fifth Generation(5G)systems,and it is expected to be a fundamental part of the future wireless communication systems as well.The Multiple-Input Multiple-Output(MIMO)technology,which is included in the IEEE 802.16j standard,still holds the most crucial position in the 4G spectrum as it promises to improve the throughput,capacity,spectral,and energy efficiency of wireless communication systems in the 2020s.This makes MIMO a viable technology for delay constrained medical and health care facilities.This paper presents an approximate closed-form expression of the ergodic capacity for the Decode-and-Forward(DF)protocol MIMO-Orthogonal Frequency Division Multiplexing(OFDM)relaying network.Although MIMO-OFDM is highly valuable for modern high-speed wireless communication systems,especially in the medical sciences,its performance degrades in multi-hop relay networks.Therefore,in this paper,an approximate closed-form expression is derived for an end-to-end ergodic capacity of multi-hop DF MIMO-OFDM wireless communication system has been presented.Monte-Carlo simulations are conducted to verify the performance of the presented analysis regarding the capacity(bits/s/Hz)for different SNR-dB values for single,2×2,4×4,and multi-hop DF MIMOOFDM systems.The presented results provide useful insights for the research on the end-to-end ergodic capacity evaluation.
文摘The next-generation wireless networks are expected to provide higher capacity,system throughput with improved energy efficiency.One of the key technologies,to meet the demand for high-rate transmission,is deviceto-device(D2D)communication which allows users who are close to communicating directly instead of transiting through base stations,and D2D communication users to share the cellular user chain under the control of the cellular network.As a new generation of cellular network technology,D2D communication technology has the advantages of improving spectrum resource utilization and improving system throughput and has become one of the key technologies that have been widely concerned in the industry.However,due to the sharing of cellular network resources,D2D communication causes severe interference to existing cellular systems.One of the most important factors in D2D communication is the spectrum resources utilization and energy consumption which needs considerable attention from research scholars.To address these issues,this paper proposes an efficient algorithm based on the idea of particle swarm optimization.The main idea is to maximize the energy efficiency based on the overall link optimization of D2D user pairs by generating an allocation matrix of spectrum and power.The D2D users are enabled to reuse multiple cellular user’s resources by enhancing their total energy efficiency based on the quality of service constraints and the modification of location and speed in particle swarm.Such constraint also provides feasibility to solve the original fractional programming problem.Simulation results indicate that the proposed scheme effectively improved the energy efficiency and spectrum utilization as compared with other competing alternatives.
基金gratefully appreciate the support offered by the KFUPM Fund received from Mr.Al-Bin Saleh donated through project MWS-90130027 to the Interdisciplinary Research Center for Membranes and Water Security,King Fahd University of Petroleum and Minerals,Saudi Arabia.
文摘Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical properties.In this study,we designed and fabricated three novel membranes with different active layers using the crosslinkers:terephthaloyl chloride,isophthaloyl chloride,and trimesoyl chloride.The crosslinkers were reacted with an aqueous solution of an aliphatic tetra-amine.Because these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization,the resultant membranes also possess different structural properties.The water contact angle of the fabricated membranes also varies;the water contact angles of 4A-3P-TPC@PSF/PET,4A-3P-TMC@PSF/PET,and 4A-3P-IPC@PSF/PET,are 68.9°,65.6°,and 53.9°,respectively.Similarly,the desalination performance of resultant membranes also showed variations,with 4A-3P-TPC@PSF/PET,4A-3P-IPC@PSF/PET,and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14,25.70,and 30.90 L·m^(−2)·h^(−1),respectively,at 2.5 MPa.The 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine,and cationic dye rhodamine B,MgCl_(2),and amitriptyline rejection rates of 98.6%,92.7%and 80.9%,respectively.The 4A-3P-TMC@PSF/PET membrane showed mediocre performance,while 4A-3P-IPC@PSF/PET membrane showed even lower performance,with a 35%rejection of methyl orange dye.
文摘Background The neutron activation analysis(NAA)is a very powerful method for multi-element analysis of samples.NAA technique needs to be developed for low neutron flux in millicuries using the 241Am-Be neutron source.Aims To optimize sample and neutron source geometry for maximumγ-ray yield for neutron activation analysis.Method Gamma ray neutron activation analysis(NAA)has been set up where a 50-millicurie Am-Be neutron source is available.In this experimental setup,the neutron source is placed at the center of a cylindrical water tank of 40 x 40 cm in xyz plan,and thermal neutrons are produced at a distance of 1.2 cm from the source.The system is used for the activation analysis of sodium carbonate,sodium chloride and copper with the gamma ray emissions of 1.37,1.73,2.25 and 2.76 MeV for 24Na and 0.511 MeV for 64Cu having half lives of 15 hrs and 12.9 hrs,respectively.The thermal neutron activation analysis has been demonstrated by placing the samples at about 1.2 cm from the neutron source.HPGe and 3x3 inch NaI(Tl)gamma ray spectrometers have been used for the gamma ray spectrometry of these activated samples with the use of a Marinelli beaker.The geometry of the sample with respect to the neutron source has been optimized for the maximumγ-ray yield in NAA.Conclusion The geometry of the sample with respect to the neutron source has been optimized for the maximumγ-ray yield in NAA.The increase in gamma ray flux distribution in the medium of water,due to the neutron source inside the tank,has been observed by a GM detector which is due to the production of short-lived 16N on activation of 16O in water.This system can also be used for promptγ-ray analysis.