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1.
J Healthc Eng ; 2023: 4845850, 2023.
Article in English | MEDLINE | ID: mdl-36814548

ABSTRACT

As one of the important applications of Internet of Health Things (IoHT) technology in the field of healthcare, wireless body area network (WBAN) has been widely used in medical therapy, and it can not only monitor and record physiological information but also transmit the data collected by sensor devices to the server in time. However, due to the unreliability and vulnerability of wireless network communication, as well as the limited storage and computing resources of sensor nodes in WBAN, a lot of authentication protocols for WBAN have been devised. In 2021, Alzahrani et al. designed an anonymous medical monitoring protocol, which uses lightweight cryptographic primitives for WBAN. However, we find that their protocol is defenseless to off-line identity guessing attacks, known-key attacks, and stolen-verifier attacks and has no perfect forward secrecy. Therefore, a patient monitoring protocol for WBAN in IoHT is proposed. We use security proof under the random oracle model (ROM) and automatic verification tool ProVerif to demonstrate that our protocol is secure. According to comparisons with related protocols, our protocol can achieve both high computational efficiency and security.


Subject(s)
Computer Security , Wireless Technology , Humans , Confidentiality , Monitoring, Physiologic , Computer Communication Networks
2.
Materials (Basel) ; 15(19)2022 Oct 06.
Article in English | MEDLINE | ID: mdl-36234268

ABSTRACT

Polytetrafluoroethylene (PTFE) plays an important role in semiconductor manufacturing. It is an important processing material for the key sealing components in the field of immersion lithography. The lack of research related to the mechanical processing of PTFE leads to many challenges in producing complex parts. This paper conducted a drilling experiment on PTFE. The effect of cutting parameters on the drilling performance was investigated. Thrust, torque, surface roughness, and drilling temperature were used to evaluate the influence of cutting parameters on drilling performance. In addition, the empirical mathematical models of thrust and torque were developed using analysis of variance (ANOVA). The results indicated that the spindle speed had the most important effect on the thrust and the feed rate had the most significant effect on the torque. The lowest values of thrust and torque were, respectively, 22.64 N and 0.12 Nm, achieved in the case of spindle speed of 5000 rev/min, and feed rate of 50 mm/min. The surface quality is also best at this cutting parameter. Studies have shown that higher spindle speeds with lower feed rates are ideal parameters for improving the drilling performance and machining quality of PTFE. In addition, it was found that the temperature differences due to different drilling depths were related to chip accumulation. Surface roughness inconsistencies at various locations in the inner wall of the hole were influenced by chip adhesion during machining. This paper provides a suggestion for optimizing cutting parameters and hole quality.

3.
Waste Manag ; 102: 541-549, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31765974

ABSTRACT

Recycling of e-waste is an effective means for e-waste management. It has made great contribution to improving environmental benefits. This paper evaluates the emission reduction benefits and efficiency of e-waste recycling in China, using the direction distance function of DEA. Calculations show that from 2013 to 2017, the total emission reduction benefits of 29 provinces in China e-waste was 6.34 billion yuan, with an average emission reduction efficiency of 0.88. The emission reduction benefits of CO2 was 390 million tons, and the average emission reduction efficiency was only 0.82. The wastewater emission reduction benefits was 570 million yuan, with an average efficiency of 0.9. The emission reduction benefits of solid waste and SO2 are 5.37 billion yuan and 400 million yuan respectively, with the same emission reduction efficiency of 0.89. E-waste recycling in China still has huge potential for emission reduction.


Subject(s)
Electronic Waste , Waste Management , China , Recycling , Solid Waste
4.
Genes Genomics ; 42(3): 283-290, 2020 03.
Article in English | MEDLINE | ID: mdl-31833047

ABSTRACT

BACKGROUND: The development efficiency of cloned cattle is extremely low (< 5%), most of them were aborted at late gestation. Based on our previous studies, some recipient cows with a cloned fetus would present as engorged uterine vessels and enlarged umbilical vessels randomly. Abortion involves both maternal and fetal factors. OBJECTIVE: Our aim was to explore this phenomenon by microRNAs expression profile analysis of maternal corpus luteum (CL), which was related to pregnancy maintenance. METHODS: The present study provided the comparison of maternal CL miRNAs expression of abnormally and normally developed cloned bovine fetus at late gestation (~ 210 days) using RNA-Seq technology. RESULTS: We selected two abnormally pregnant cows (abnormal group, AG) and three normally pregnant cows (normal group, NG) and acquired valid reads of 9317,261-12,327,185 (~ 84.53-91.28%) from five libraries. In total, we identified 981 conserved miRNAs and 223 novel miRNAs. 1052 miRNAs were co-expressed, 124 miRNAs were uniquely expressed in AG, and 93 miRNAs were uniquely expressed in the NG. Compared with NG, 11 were significantly overexpressed, and 22 were downregulated (p < 0.05) at AG among 1052 co-expressed miRNAs. The differentially expressed miRNAs-targeted genes were further analyzed by Gene Ontology and KEGG pathway analysis. Notably, the steroid biosynthesis pathway was a significantly enriched term (p < 0.01), which may affect the secretion of progesterone. CONCLUSION: Our research suggested that abnormal miRNAs expression of bovine maternal CL may affect the pregnant status at late gestation.


Subject(s)
Cattle/embryology , Cattle/genetics , Corpus Luteum/metabolism , Fetus/metabolism , MicroRNAs/metabolism , Animals , Cattle/metabolism , Female , Gene Expression Regulation/genetics , Gene Ontology , Gestational Age , MicroRNAs/genetics , Pregnancy , Progesterone/genetics , Progesterone/metabolism , RNA-Seq
5.
J Clin Lab Anal ; 33(6): e22918, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31131498

ABSTRACT

BACKGROUNDS: One of the limitations of somatic cell nuclear transfer (SCNT) strategy to generate genetically modified offspring is the low birth rate. Placental dysfunction is one of the causes of abortion. Circular RNA (circRNA) is noncoding RNA which functions as microRNA (miRNA) sponges in biological processes. METHODS: Two aberrant pregnant placenta (aberrant group, AG) and three normal pregnant placenta (normal group, NG) during late gestation (180-210 days) with bovine SCNT fetus were collected for high-throughput sequencing and analyzed. The host genes of differentially expressed (DE) circRNAs were predicted. And the microRNAs (miRNAs) which could interact with DE circRNAs were analyzed. Then, the expressional level of partial DE circRNAs and corresponding host genes was verified through qRT-PCR. At last, the function of host genes was analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). RESULTS: Altogether 123 differentially expressed circRNAs between two groups were identified, which were found related to 60 host genes and 32 miRNAs. The top 10 upregulated circRNAs were bta_circ_0012985, bta_circ_0013071, bta_circ_0013074, bta_circ_0016024, bta_circ_0013068, bta_circ_0008816, bta_circ_0012982, bta_circ_0013072, bta_circ_0019285, and bta_circ_0013067. The top 10 downregulated circRNAs were bta_circ_0024234, bta_circ_0017528, bta_circ_0008077, bta_circ_0003222, bta_circ_0007500, bta_circ_0020328, bta_circ_0011001, bta_circ_0016364, bta_circ_0008839, and bta_circ_0016049. The qRT-PCR results showed consistent trend with sequencing analysis result, while host genes had no statistic difference. The GO and KEGG analyses of the host genes suggested that abnormal circRNA expression may play multiple roles in placental structure and dysfunction. CONCLUSION: The abnormal circRNA expression may be one of reasons of placental dysfunction, leads to abortion of bovine SCNT fetus.


Subject(s)
Nuclear Transfer Techniques , Placenta/physiology , RNA, Circular/genetics , Animals , Cattle , Female , Gene Expression Regulation, Developmental , Gene Ontology , Gestational Age , MicroRNAs/genetics , Placenta/physiopathology , Pregnancy , Reproducibility of Results
6.
RSC Adv ; 9(61): 35566-35578, 2019 Oct 31.
Article in English | MEDLINE | ID: mdl-35528069

ABSTRACT

Protean mesoporous silica nanoparticles (MSNs) are propitious candidates over decades for nanoscale drug delivery systems due to their unique characteristics, including (but not limited to) changeable pore size, mesoporosity, high drug loading capacity, and biodegradability. MSNs have been drawing considerable attention as competent, safer and effective drug delivery vehicles day by day by their towering mechanical, chemical and thermal characteristics. Straightforward and easy steps are involved in the synthesis of MSNs at a relatively cheaper cost. This review reports Stober's synthesis, the first proposed synthesis procedure to prepare micron-sized, spherical MSNs, followed by other modifications later on done by scientists. To ensure the safety and compatibility of MSNs with biological systems, the hemocompatibility evaluation of MSNs using human red blood cells (RBCs) is a widely welcomed exercise. Though our main vision of this overview is to emphasize more on the hemocompatibility of MSNs to RBCs, we also brief about the synthesis and widespread applications of multifaceted MSNs. The strike of different parameters of MSNs plays a crucial role concerning the hemolytic activity of MSNs, which also has been discussed here. The inference is derived by centering some feasible measures that can be adopted to cut down or stop the hemolytic activity of MSNs in the future.

7.
Carbohydr Polym ; 179: 135-144, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-29111036

ABSTRACT

The effect of gene silencing by survivin siRNA (siSurvivin) on the proliferation and apoptosis of lung tumor has been attracted more interest. GABAB receptor ligand-directed nanoparticles consisting of baclofen functionalized trimethyl chitosan (Bac-TMC) as polymeric carriers, tripolyphosphate (TPP) as ionic crosslinker, and siSurvivin as therapeutic genes, were designed to enhance the survivin gene silencing. GABAB receptor agonist baclofen (Bac) was initially introduced into TMC as a novel ligand. This Bac-TMC/TPP nanoparticles increased the uptake of survivin siRNA through the interaction with GABAB receptor, further resulted in efficient cell apoptosis and gene silencing. For siRNA-loaded nanoparticles pulmonary delivery, mannitol was utilized for it delivery into pressurized metered dose inhalers (pMDI). The fine particle fractions of this formulation was (45.39±2.99)% indicating the appropriate deep lung deposition. These results revealed that this pMDI formulation containing Bac-TMC/TPP nanoparticles would be a promising siRNA delivery system for lung cancer treatment.


Subject(s)
Antineoplastic Agents/administration & dosage , GABA-B Receptor Agonists/chemistry , Inhibitor of Apoptosis Proteins/genetics , Lung Neoplasms/drug therapy , Nanoparticles/chemistry , RNA, Small Interfering/administration & dosage , A549 Cells , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Baclofen/chemistry , Cell Proliferation/drug effects , Chitosan/chemistry , Drug Carriers/administration & dosage , Drug Carriers/chemistry , Gene Silencing/drug effects , Humans , Inhibitor of Apoptosis Proteins/metabolism , Ligands , Mannitol/chemistry , Metered Dose Inhalers , Particle Size , Polyphosphates/chemistry , RNA, Small Interfering/chemistry , RNA, Small Interfering/genetics , Survivin
8.
J Med Syst ; 38(9): 91, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24994512

ABSTRACT

Patient's privacy-preserving, security and mutual authentication between patient and the medical server are the important mechanism in connected health care applications, such as telecare medical information systems and personally controlled health records systems. In 2013, Wen showed that Das et al.'s scheme is vulnerable to the replay attack, user impersonation attacks and off-line guessing attacks, and then proposed an improved scheme using biometrics, password and smart card to overcome these weaknesses. However, we show that Wen's scheme is still vulnerable to off-line password guessing attacks, does not provide user's anonymity and perfect forward secrecy. Further, we propose an improved scheme to fix these weaknesses, and use the applied pi calculus based formal verification tool ProVerif to prove the security and authentication.


Subject(s)
Computer Communication Networks , Computer Security , Electronic Health Records , Patient Identification Systems , User-Computer Interface , Algorithms , Confidentiality , Health Information Exchange , Humans , Software Design
9.
Ying Yong Sheng Tai Xue Bao ; 22(4): 857-65, 2011 Apr.
Article in Chinese | MEDLINE | ID: mdl-21774304

ABSTRACT

By the methods of static chamber and gas chromatography, this paper studied the effects of fire disturbance on the seasonal dynamics and source/sink functions of CH4, CO2 and N2O emissions from Betula platyphylla-forested wetland as well as their relations with environmental factors in Xiaoxing' an Mountains of China. In growth season, slight fire disturbance on the wetland induced an increase of air temperature and ground surface temperature by 1.8-3.9 degrees C and a decrease of water table by 6.3 cm; while heavy fire disturbance led to an increase of air temperature and 0-40 cm soil temperature by 1.4-3.8 degrees C and a decrease of water table by 33.9 cm. Under slight or no fire disturbance, the CH4 was absorbed by the wetland soil in spring but emitted in summer and autumn; under heavy fire disturbance, the CH4 was absorbed in spring and summer but emitted in autumn. The CO2 flux had a seasonal variation of summer > spring = autumn under no fire disturbance, but of summer > autumn > spring under fire disturbance; and the N2O flux varied in the order of spring > summer > autumn under no fire disturbance, but of autumn > spring > summer under slight fire disturbance, and of summer > spring = autumn under heavy fire disturbance. At unburned site, the CO2 flux was significantly positively correlated with air temperature and ground surface temperature; at slightly burned site, the CO2 flux had significant positive correlations with air temperature, 5-10 cm soil temperature, and water table; at heavily burned sites, there was a significant positive correlation between CO2 flux and 5-40 cm soil temperature. Fire disturbance made the CH4 emission increased by 169.5% at lightly burned site or turned into weak CH4 sink at heavily burned site, and made the CO2 and N2O emissions and the global warming potential (GWP) at burned sites decreased by 21.2% -34.7%, 65.6% -95.8%, and 22.9% -36.6% respectively, compared with those at unburned site. Therefore, fire disturbance could decrease the greenhouse gases emission from Betula platyphylla-forested wetland, and planned firing could be properly implemented in wetland management.


Subject(s)
Betula/growth & development , Carbon Dioxide/analysis , Fires , Methane/analysis , Wetlands , China , Ecosystem , Environmental Monitoring , Greenhouse Effect , Nitrous Oxide/analysis , Seasons
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