ABSTRACT
Objective To investigate the value of single photon emission computed tomography/computed tomography(SPECT/CT)fusion imaging for post-implantation dose verification of 125I particles in patients with bone metastases.Methods Forty patients with metastatic bone tumors treated with 125I particles implantation were selected.Within 24 h after 125I particles implantation,patients underwent SPECT/CT fusion imaging and the radioactivity per unit(RPU)was calculated.The treatment planning system(TPS)was then used to obtain the isodose profiles of SPECT/CT fusion imaging results and to calculate the tumor target coverage.The patient's preoperative and postoperative 1 month clinical outcomes,including local tumour remission,pain assessment,quality of life and serum alkaline phosphatase(ALP)levels were compared,and a receiver operating characteristic(ROC)curve was applied to evaluate the predictive value of tumor target coverage on postoperative outcomes.Results The mean number of particles implanted in the target area was 32.52±12.87.Within 24 h of 125I particles implantation,SPECT/CT fusion imaging analysis confirmed a strong positive correlation between the RPU of the radioactive concentration area and the mean dose received by the patient(r=0.786,P<0.05).The predicted area under the curve(AUC)for local tumor remission,pain relief,quality of life improvement and change in ALP levels was 0.789,0.757,0.804 and 0.833,respectively.Conclusion SPECT/CT fusion imaging can be used for postoperative dose verification of 125I particles for metastatic bone tumors and has some predictive value for clinical outcomes.
ABSTRACT
BACKGROUND:At present,a large number of studies have found that Liuwei Dihuang Pill can be used to treat osteoporosis,but there are few related studies on the differentiation and mineralization of osteoblasts induced by wear particles using Liuwei Dihuang Pill. OBJECTIVE:To investigate the positive effect of different concentrations of Liuwei Dihuang Pill-containing serum on titanium particle-induced mouse MC3T3-E1 osteoblast in vitro osteolysis model. METHODS:Drug-containing serum was extracted after oral administration of Liuwei Dihuang Pill.The best concentration of Liuwei Dihuang Pill-containing serum and titanium particles on the viability of MC3T3-E1 cells was screened.MC3T3-E1 cells were divided into three groups.The blank group was given osteoblastic differentiation culture.The model group was given titanium particles(5 μg/mL)ossification culture.The drug-containing serum group was given titanium particles(5 μg/mL)+ Liuwei Dihuang Pill-containing serum(10%,15%and 20%doses).Osteoblast viability was detected by CCK-8 assay.Cell alkaline phosphatase activity was detected by alkaline phosphatase staining.Cell mineralization was detected by silver nitrate(Von Kossa)and alizarin red staining.Expression levels of bone differentiation-related genes Runx-2,Osterix,Ocn,Axin,Alp,and Opn were detected by qRT-PCR.Wnt/β-catenin signaling pathways β-catenin,p-GSK-3β,GSK-3β,Runx2 and Osterix protein expression levels were detected by western blot assay. RESULTS AND CONCLUSION:(1)Liuwei Dihuang Pill-containing serum culture reversed the decrease in alkaline phosphatase activity of MC3T3E-1 cells induced by titanium particles,increased the alizarin red staining and calcification of MC3T3E-1 cells,increased the expression of osteogenesis-related genes in MC3T3E-1 cells,and increased the expression of proteins related to the Wnt/β-catenin signaling pathway.(2)These findings indicate that Liuwei Dihuang Pill-containing serum can reverse the inhibitory effect of titanium particles on the differentiation and mineralization of osteoblasts,upregulate the expression of osteogenesis-related genes,and its mechanism is related to the regulation of Wnt/β-catenin signaling pathway,suggesting that Liuwei Dihuang Pill is expected to become an effective drug for preventing aseptic loosening of artificial joints.
ABSTRACT
BACKGROUND:Periprosthetic osteolysis is the most common long-term complication of total joint arthroplasty.Many studies suggest that the inflammasome may play an important role during the osteolysis.Melatonin is a rhythm-regulated hormone secreted by the pineal gland with many functions including anti-inflammatory,anti-oxidation,and antitumor,but its effects on osteolysis and inflammasome have yet to be explored. OBJECTIVE:To explore the effect of melatonin on the osteolysis induced by wear particles and the role of melatonin on the activation of NLRP3 inflammasome. METHODS:(1)In vivo test:Fifteen C57BL/6 mice were randomly divided into sham operation group,osteolysis group and melatonin group by random number table method,with 5 mice in each group.The osteolysis model of the osteolysis group and the melatonin group was established by injecting cobalt-chromium-molybdenum(CoCrMo)particles into the sagittal suture of the skull.After injection,the melatonin group was intraperitoneally injected with 50 mg/(kg·d)of melatonin for 14 consecutive days.After drug intervention,the mouse calvarium was collected for micro-CT analysis to observe the micro-structural changes around the sagittal suture.(2)In vitro test:Mouse bone marrow-derived macrophages and THP-1 cells(which had been induced to differentiate into macrophages)were taken and divided into seven groups:normal group,lipopolysaccharide group,lipopolysaccharide+CoCrMo group and melatonin 0.5,1,1.5,2 mmol/L groups(lipopolysaccharide and CoCrMo were added to the melatonin intervention groups).After the intervention for 6 hours,the expression of related proteins(NLRP3,Caspase-1,interleukin-1β,and gasdermin D,gasdermin D-N terminal)in the inflammasome of cell lysate or cell culture supernatant was detected by western blot assay.Cytotoxicity and cell death were observed through lactate dehydrogenase release and live-dead fluorescence staining. RESULTS AND CONCLUSION:(1)In vivo test:Micro-CT scanning 3D reconstruction images showed that the bone mass around the sagittal suture of the skull of mice in the osteolysis group was significantly reduced,and the bone tissue structure was severely damaged.Compared with the osteolysis group,the bone mass around the sagittal suture of the skull in the melatonin group was significantly increased,and the destruction of tissue structure was reduced.(2)In vitro test:For mouse bone marrow-derived macrophages,lipopolysaccharide significantly up-regulated NLRP3 protein expression in cell lysate,and melatonin intervention could reduce NLRP3 protein expression in a dose-dependent manner.CoCrMo particles significantly up-regulated the protein expressions of the gasdermin D-N terminal in cell lysate and Caspase-1 and interleukin-1β in the supernatant of cell culture,while melatonin intervention could reduce the expression of these proteins in a dose-dependent manner.For THP-1 cells,the protein expressions of Caspase-1 and interleukin-1β in the supernatant of cell culture were significantly up-regulated by CoCrMo particles,and the expression of these proteins was decreased dose-dependent by melatonin intervention.Lactate dehydrogenase release and live-dead fluorescence staining showed that CoCrMo particles significantly increased the release of lactate dehydrogenase and cell death in the supernatant of mouse bone marrow-derived macrophage culture,and melatonin intervention could reduce the release of lactate dehydrogenase and cell death.(3)The results show that melatonin can inhibit particle-induced inflammasome activation and pyroptosis to suppress periprosthetic osteolysis.
ABSTRACT
BACKGROUND:Tabersonine has shown good therapeutic effects in diseases such as myocardial remodeling,acute kidney injury and lung injury due to its anti-inflammatory biological activity.Prosthetic wear particles often lead to aseptic inflammation,and the massive release of inflammatory factors further promotes periprosthetic bone destruction and bone loss;however,there are no basic studies on the efficacy of tabersonine on periprosthetic osteolysis. OBJECTIVE:To investigate the effects of tabersonine on osteoclast activation,expression of inflammatory factors and inflammatory osteolysis induced by wear particles. METHODS:(1)Cell experiment:RAW264.7 cells were divided into four groups for culture.A complete medium was added in the control group.Osteoclast induction medium(50 ng/mL RANKL+complete medium)was added to the osteoclast induction group.1 and 5 μmol/L tabersonine was added for 4 hours,and then osteoclast induction medium was added to the low-and high-dose tabersonine groups,respectively.After 5 days of induction,tartrate-resistant acid phosphatase staining,F-actin staining and RT-PCR were performed.(2)Animal experiments:Twenty C57BL/6J mice were randomly divided into sham operation group,osteolysis group,low-dose tabersonine group and high-dose tabersonine group(n=5 per group).Skull osteolysis model of the skull was established by injecting titanium pellets on the skull surface in the osteolysis group,low-dose tabersonine group and high-dose tabersonine group.On day 2 after model establishment,mice in the low-dose and high-dose tabersonine groups received intraperitoneal injections of 10 and 20 mg/kg tabersonine every 2 days,respectively.2 weeks after surgery,mouse sera were collected for detecting inflammatory factors(interleukin 1β,interleukin 6,and tumor necrosis factor α),and cranial bones were collected for micro-CT scan and bone parameter analysis. RESULTS AND CONCLUSION:(1)Cellular experiments:Tartrate-resistant acid phosphatase staining and F-actin staining showed that compared with the osteoclast induction group,low-dose and high-dose tabersonine significantly inhibited osteoclast activation and bone resorption,and the inhibition was more significant in the high-dose tabersonine group.RT-PCR results showed that compared with the control group,the mRNA expressions of three kinds of inflammatory factors were increased in the osteoclast induction group(P<0.01).Compared with the osteoclast induction group,the mRNA expressions of three kinds of inflammatory factors were decreased in low-and high-dose tabersonine groups(P<0.01),and the decrease was more obvious in the high-dose tabersonine group.(2)Animal experiments:Compared with the sham operation group,the levels of three kinds of inflammatory factors were increased in the osteolysis group(P<0.01).Compared with the osteolysis group,the levels of three kinds of inflammatory factors were decreased in the low-and high-dose tabersonine groups(P<0.05,P<0.01),and the decrease was more obvious in the high-dose tabersonine group.The micro-CT scan results revealed that titanium particles caused the destruction of cranial osteolysis,and tabersonine could inhibit the osteolysis induced by titanium particles,especially in the high-dose tabersonine group.(3)The results confirm that tabersonine can enhance the osteolysis and bone destruction induced by titanium particles by inhibiting the release of inflammatory factors and down-regulating the bone absorption function of osteoclasts.
ABSTRACT
BACKGROUND:In addition to apoptosis,recent studies have discovered novel forms of programmed cell death in periprosthetic osteolysis,which is involved in regulating local chronic inflammation and the outcome of osteoblast and osteoclast under pathological conditions.This has an important value for the treatment and prognosis of periprosthetic osteolysis. OBJECTIVE:To provide new ideas and strategies for the prevention and treatment of periprosthetic osteolysis by summarizing studies on the novel forms of programmed cell death. METHODS:The first author used the computer to search the articles published from 2005 to 2022.Chinese search terms"wear particles,periprosthetic osteolysis,programmed cell death,apoptosis,autophagy,pyroptosis,necrotizing apoptosis,iron death"were used to search the databases of CNKI,WanFang and VIP.English search terms"osteolysis,wear debris,wear particles,peri*prosthetic osteolysis,PPOL,aseptic loosening,autophagy,regulated cell death,programmed cell death,apoptosis,pyroptosis,autophagic cell death,autophagy,necroptosis,ferroptosis"were used for search in PubMed and Web of Science databases.A total of 68 articles were finally included according to the inclusion criteria. RESULTS AND CONCLUSION:(1)Inadequate or excessive activation of autophagy can cause cell death,inhibit bone formation,and promote bone resorption,leading to bone metabolism disorders and osteolysis.(2)Recent studies have paid close attention to pyroptosis in periprosthetic osteolysis,where the Nod-like receptor,pyrin containing 3 inflammasome plays an important role in local inflammation.Inhibiting pyroptosis can effectively alleviate osteolysis.(3)In vitro studies have shown that necroptosis can inhibit the formation and function of osteoblasts and osteoclasts,affecting the process of osteolysis and destruction.(4)Ferroptosis is the newest form of programmed cell death,which is regulated by complex signaling pathways and mechanisms,but is not yet fully understood.(5)Autophagy,pyroptosis,necroptosis,and ferroptosis play important roles in the development of periprosthetic osteolysis,and their associated signaling pathways and genes require further investigation.
ABSTRACT
BACKGROUND:Bioactive glass is a multifunctional synthetic composite material that releases active ions slowly and exhibits certain biological activities after affinity with tissues.Their versatility stems from the versatility of their preparation processes and components,allowing them to be applied in different clinical scenarios. OBJECTIVE:To review the main application forms,application fields of bioactive glass,as well as the influence of doping different elements on its function. METHODS:A literature search was conducted across WanFang Medical Database,CNKI Database,PubMed Database,and Web of Science Database,using the search terms"bioactive glass,slow-release ions,bone tissue engineering,composite scaffold,tissue regeneration and repair,biomedical engineering"in Chinese and English.The timeframe was limited from 2000 to 2023.Finally,88 articles were included for review. RESULTS AND CONCLUSION:(1)In terms of application forms,bioactive glass can be fabricated as coatings,particles,bone cements,and scaffolds according to needs.Coatings have the potential to enhance the biological activity of implants,yet they are susceptible to instability as a result of degradation.Particles offer a viable solution for the repair of irregular bone defects;however,particles produced through traditional methods often possess limited functionality.Bone cement provides the benefits of minimal invasiveness and injectability,yet its application is restricted to smaller bone defects.Scaffolds exhibit excellent mechanical properties and are commonly used for larger-sized bone defects,yet they have limited toughness.(2)In terms of applications,bioactive glass can be used in a variety of tissue regeneration and repair and disease treatment fields,including dentistry,orthopedics,soft tissue engineering,and cancer.(3)In terms of element doping,the addition of specific elements to bioactive glass not only improves its mechanical properties but also endows it with special biological functions such as bioactivity,degradability,and antibacterial properties.(4)Biologically active glass is a versatile material that can be used in different forms and functions by adjusting the preparation process and element doping to meet various clinical needs in bone tissue engineering and is widely used in the field of biomedical engineering.
ABSTRACT
Objective To propose a Kaczmarz algorithm-based fast reconstruction method of magnetic particle imaging to solve the problems of magnetic particle tomography in prolonged imaging time and computational complexity.Methods Firstly,the convergence speeds of the classical Kaczmarz algorithm and its variant algorithms were analyzed,and the number of iterations and computational time under arbitrary matrices were calculated.Secondly,the abilities of Euclidean distance and cosine distance in differentiating system data were compared,and the cosine distance-based K-means algorithm was employed to enhance the computational capability of block Kaczmarz algorithm,shorten the system matrix reconstruction time,and ultimately fast reconstruction of magnetic particle imaging was realized.The effectiveness of the proposed algorithm was verified through computer simulation.Results The proposed algorithm reduced greatly the reconstruction time and improved the spatial resolution and quality of the reconstructed images.Conclusion The proposed algorithm enables fast reconstruction of magnetic particle imaging and behaves well in reconstruction of data containing noise.[Chinese Medical Equipment Journal,2024,45(1):9-14]
ABSTRACT
Particle radiotherapy is a new type of radiotherapy with superior targeting and precision for more accurate radiotherapy.Considering the complexity of the particle beams and the different lesion sites and physique of patients,a high-precision beam monitoring system which enables the monitoring of the spatial and energy distributions of the beams,such as position,dose and other important parameters,is needed to ensure the efficacy of particle radiotherapy.The beam monitoring system plays a crucial role in the safety and accuracy of particle therapy.By monitoring vital parameters such as the position and dose of the beams,the treatment plan can be adjusted in real-time,thus ensuring accurate lesion irradiation while minimizing the effects on the surrounding healthy tissues.Consequently,the development and validation of such a beam monitoring system are essential in particle radiotherapy.Herein the advances in beam monitoring for quality assurance for particle therapy are summarized.It gives a brief description of particle radiotherapy,emphasizing the significance of beam monitoring systems for particle radiotherapy,focuses on the development of particle beam monitoring and introduces different types of detectors,along with their applications and research advancements,and explores the future development trend of beam monitoring system and potential challenges it may face.
ABSTRACT
Background The serious air pollution of highway toll booths poses a high occupational exposure risk to toll collectors. It is urgent to develop purification methods suitable for airborne particles and microbial pathogens in highway toll booths. Objective To verify the purification effect of low temperature plasma air purifiers on airborne particles and microbes in highway toll booths. Methods Based on controlled-intervention design, we selected three toll booths in an expressway toll station as on-site experimental locations for 6 d (no-intervention period: the low-temperature plasma purifier was turned off in the first three days; intervention period: the purifier was turned on from 9:00 to 17:00 in the following three days). The indoor and outdoor PM2.5 and PM10 concentrations were continuously monitored during the study. At 9:00, 12:00, and 17:00 of every day during the experiment, indoor and outdoor air samples were collected to analyze the concentration of airborne culturable colonies with a plankton sampler. Airborne particle samples were collected in the outermost exit continuously from 9:00 to 17:00 every day during the experiment using a medium flow particulate sampler, and the species and relative abundance of fungi and bacteria contained in the samples were analyzed by gene sequencing. Independent-sample t test was used to compare the concentration of indoor PM2.5, PM10, and culturable colonies between the intervention period and the non-intervention period. α diversity analysis, β diversity analysis, and t test were used to compare the diversity and relative abundance of specific species of bacteria and fungi, as well as typical pathogenic bacteria and fungi in the samples between the non-intervention period and the intervention period to reflect the purification effect of low temperature plasma air purifier on airborne PM2.5, PM10, and microorganisms. Results During the intervention period, the mean indoor concentrations of PM2.5, PM10, and culturable colonies were lower than those of the no-intervention period (P<0.01 or P<0.001). The ratios of indoor to outdoor concentration (I/O) of PM2.5 and PM10 during the intervention period were significantly lower than those of the no-intervention period (P<0.001), except the I/O of culturable colonies. Compared with the average concentration at 9:00, the average cleaning rates at 12:00 and 17:00 for PM2.5 were 49.0% and 46.1%, for PM10 were 49.7% and 45.4%, for airborne culturable colonies were 50.8% and 49.9%, respectively. The β diversity analysis showed that there were significant differences in composition at the level of species of bacteria, and at the levels of genus and species of fungi between the intervention and the no-intervention periods. The relative abundances of 10 species of bacteria such as Lactobacillus and 7 species of fungi such as Torula in the intervention period were significantly lower than those in the non-intervention period, but the relative abundances of fungi such as unclassified_f_cladosporiaceae, trichomerium, and cercospora were higher (P<0.05). For typical pathogenic bacteria, the relative abundances of Lactobacillus and Clostridium_sensu_stricto_1 during the intervention period were 73.5% and 86.9% lower than those in the no-intervention period, and the relative abundance of Talaromyces was 53.5% lower (P<0.05). Conclusion Low temperature plasma air purifier has a good purification effect on indoor PM2.5, PM10, and culturable colonies in highway toll booths, and likely a limited effect on some fungi.
ABSTRACT
@#Objective To identify the peak 2 protein on the right side of the main peak of size exclusion chromatograghy-high performance liquid chromatography(SEC-HPLC)in freeze-dried human rabies vaccine(Vero cell)stock solution(without human blood albumin),so as to determine the protein composition of the peak and ensure the vaccine quality.Methods The lyophilized human rabies vaccine(Vero cells)stock solution(without human blood albumin)was analyzed by SECHPLC,of which the peak 2 on the right side of the main peak was collected and concentrated by ultrafiltration,then reduced by dithiothreitol(DTT),alkylated by iodoacetamide (IAM) and hydrolyzed by Trypsin. The products were analyzed by nano LC-MS/MS.Results Four proteins were successfully identified in the right peak 2 of SEC-HPLC main peak in lyophilized human rabies vaccine(Vero cell)stock solution(without human blood albumin),and the number of matching peptides for a single protein ranged from 59 to 79. The number of single protein-matching characteristic peptides ranged from 6 to 12. The detection times of single protein-matching characteristic peptide segments ranged from 20 to 36 times. The sequence coverage of the identified proteins ranged from 37. 40% to 64. 31%. A total of 280 peptides participated in the statistics,and the mass spectrum deviation was less than 0. 15 Da.Conclusion The peak 2 on the right side of SEC-HPLC main peak of lyophilized human rabies vaccine(Vero cell)stock solution(without human blood albumin)is derived from rabies strain 4a GV,which is the vaccine particle dissociation.
ABSTRACT
@#Objective To express and identify recombinant adenovirus type 5-Norovirus(NoV)GⅡ.4-VP1 virus-like particles(VLPs)in 293T cells. Methods The recombinant adenovirus plasmids pAd5-eGFP and pAd5-NoV-GⅡ.4-VP1 were transfected into 293T cells respectively,and the recombinant adenovirus rAd5-eGFP and rAd5-NoV-GⅡ.4-VP1 were rescued. The rAd5-eGFP was subcultured in 293T cells to verify the function of the vector. The rAd5-NoV-GⅡ.4-VP1 was subcultured in293T cells,expressed and purified,and then NoV-GⅡ.4-VLP was formed by self-assembly,which was detected by Western blot,ELISA and observed by transmission electron microscope. Results The green fluorescence of the recombinant adenovirus rAd5-eGFP of various generations was observed under microscope,and the brightness increased with the increase of generations. NoV-GⅡ.4-VP1 protein was expressed in the harvested solution of recombinant adenovirus rAd5-NoV-GⅡ.4-VP1 of various generations,with a relative molecular mass of about 58 900. NoV-GⅡ.4-VLP showed specific binding to the rabbit anti-NoV-GⅡ.4-VP1 serum;it had similar conformation to natural NoV virus particles and can effectively identify NoV receptors in volunteer saliva samples;microscopic observation showed that the morphology was complete and spherical,with a diameter of 43. 5 — 58. 3 nm,while there were a few protrusions on the surface of the particles,which might be the P domain exposedon the particle surface during self-assembly of VP1. Conclusion The expressed recombinant adenovirus NoV-GⅡ. 4-VLP has complete VLP structure and good specificity,and is expected to be used in the related research of NoV adenovirus vector vaccine.
ABSTRACT
Aims: The present study aim was to evaluate influence of particle size on the phytochemical, antioxidant and anti-inflammatory properties of powder of trunk bark Parkia biglobosa. Study Design: This is an experimental study Place and Duration of Study: The study was realized in the Phytomedicine and Medicine Research-Development (LR-D/PM) laboratories of the Health Sciences Research Institute (IRSS) of Ouagadougou in Burkina Faso. Methodology: The powder was sieved and classified into four particle sizes: coarse, moderately fine, fine, and very fine. An aqueous decoction was then made from these powders. The extraction yields, qualitative phytochemical composition, and the estimation of polyphenol compound content were determined. The antioxidant effect of the extracts was obtained using four antioxidant models: ABTS, DPPH, FRAP, and LPO. The anti-inflammatory activity was evaluated against the soybean 15-lipoxygenase. Results: Decreasing the particle size from coarse to very fine resulted in an approximately two-fold increase in extraction yield (from 12.19 to 29.05); an approximately two-fold increase in antioxidant and anti-inflammatory activities: ABTS (from 4.1 ± 0.1 to 1.4 ± 0.3 µg/mL); DPPH (from 7.3 ± 0.1 to 3.1 ± 0.3 µg/mL); FRAP (from 885.6 ± 84 to 6973 ± 21 mmol EAA/g), and LOX (from 34.09 ± 1.43 to 2.88 ± 0.65 µg/mL). Moreover, the modification of the particle size has also improved the LPO inhibitory activity and total phenolic and flavonoid contents. The increased surface area in contact with the extraction solvent may explain the interesting effect of the very fine powder Conclusion: The very fine powder offers more significant antioxidant and anti-inflammatory activities. Therefore, this powder can be suggested to develop a phytomedicine against inflammatory diseases
ABSTRACT
This study was conducted during 2021-22 considering various vegetable growing farmers in Unnao District (U.P.), India to find out the effect of using sewage as the only source of irrigation to their crops. In this study, 250 surface soil samples collected from farmer’s field were analyzed for Physical as well as Chemical parameters. The physical properties of soils improved due to sewage application; Bulk density ranged from 1.04 to 1.42 Mg m-3 and particle density ranged between 2.61 to 2.88 Mg m-3 and Porosity ranged between 53.4 to 61.85 with mean of 56.87 percent. Chemical Parameters such as pH, E.C., O.C., Available N, P & K were also analyzed and the results indicated that soils had a mean normal pH of 7.2, E.C. of 0.76 dSm-1, O.C. of 56.80. Available nitrogen ranged from 565 – 1217 kg ha-1 with mean of 879.56 kg ha-1.The Phosphorus availability was found ranging from 14.40 – 33.5 kg ha-1 with a mean of 23.98 kg ha-1, while Potassium was found with a mean of 205.30 kg ha-1 in range of 174 – 235 kg ha-1.
ABSTRACT
Fuel pellets are a popular form of biomass energy due to their high energy density, ease of handling, and reduced emissions. The quality of fuel pellets is influenced by various factors, including the moisture content and particle size of the raw materials (Soybean straw and cotton stalk) used during the pelletization process. In this study, the effect of moisture content and particle size on the characteristics of fuel pellets produced using a flat die type pelleting machine was investigated. Different moisture content levels (ranging from 20 to 30%) and particle sizes (ranging from 4 to 8 mm) were used to pelletize a biomass feedstock. The pellet characteristics, including pellet durability, bulk density and water resistance and energy consumption were evaluated. The results showed that both moisture content and particle size significantly influenced the characteristics of the fuel pellets as well as energy consumption. Based on the findings, an optimal moisture content of 25% and particle size of 6 mm were determined for producing fuel pellets with desirable characteristics and low energy consumption was required using the flat die type pelleting machine. These results can provide valuable insights for biomass pellet producers and researchers in optimizing the pelletization process to achieve high-quality fuel pellets with improved properties.
ABSTRACT
A study was carried out after harvest of rabi season crop during 2020-2021 to find out the vertical variability in status of physical properties in Vertisol and Inceptisol under different land uses. Samples were collected in triplicate from six different land use practices (forest, uncultivated, soybean-wheat, rice-wheat, soybean - chickpea and maize-wheat) at four depths (0-15, 15-30 30-45 and 45-60 cm) Gwalior and Jabalpur regions. For statistical analysis of data in factorial RBD different soil type were considered as factor A ,land use practices as factor B and three replications. Physical properties significantly affected by soil type. It was observed in different land use practices significantly affected in WHC. Under different soil type content of sand, silt and bulk density were higher in Inceptisol as compared to vertisol, however content of clay, porosity and (water holding capacity) WHC were higher Vertisol as compare to Inceptisol. WHC, bulk density and clay was found increased down the depth except porosity, sand in Vertisol while content of sand and bulk density was found increased down to depth except WHC, porosity and clay in Inceptisol.
ABSTRACT
Electrical Discharge Machine (EDM) parameters have a significant influence on machining characteristic like material removal rate (MMR) and tool wear rate (TWR). Inconel 718, which is widely used in the Medical, Marine, Architectural and food processing industries, is used as a work material. The tool electrode materials used are brass and copper. Experiments are conducted using face centered central composite design to determine the effects of process parameters like current rate, pulse on time, pulse off time and concentration of titanium carbide nano particle in dielectric fiuid. Based upon the experimental outcomes, the effect of brass and copper electrodes during electric discharge machining of Inconel 718 using nano particles mixed dielectric fiuid was investigated.
ABSTRACT
To investigate the crucial role of particle size in the biological effects of nanoparticles, a series of mesoporous silica nanoparticles (MSNs) were prepared with particle size gradients (50, 100, 150, 200 nm) with the traditional Stober method and adjusting the type and ratio of the silica source. The correlation between toxicity and size-caused biological effects were then further examined both in vitro and in vivo. The results indicated that the prepared MSNs had a uniform size, good dispersal, and ordered mesoporous structure. Hemolytic toxicity was found to be independent of particle size. At the cellular level, MSNs with smaller particle sizes were more readily internalized by cells, which initiated to more intense oxidative stress, therefor inducing higher cytotoxicity, and apoptosis rate. In vivo studies demonstrated that MSNs primarily accumulated in the liver and kidneys of mice. Pharmacokinetic analysis revealed that larger MSNs were eliminated more efficiently by the urinary system than smaller MSNs. The mice's body weight monitoring, blood tests, and pathological sections of major organs indicated good biocompatibility for MSNs of different sizes. Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Zhejiang Chinese Medical University. Overall, this study prepared MSNs with a particle size gradient to investigate the correlation between toxicity and particle size using macrophages and endothelial cells. The study also examined the biosafety of MSNs with different particle sizes in vivo and in vitro, which could help to improve the safety design strategy of MSNs for drug delivery systems.
ABSTRACT
Objective To investigate the effect of left ventricular assist device (LVAD) and aortic graft angle on hemodynamics of aortic valve. Methods Three models of aorta and aortic valve with 45°, 60° and 90° anastomosis angles between LVAD and aorta were constructed, and an in vitro pulsating table was built for in vitro experiments. Using particle image velocimetry (PIV) system, three moments in the cardiac cycle ( T1 systolic peak, T rapid closure, T3 diastolic peak), were selected to study the hemodynamic state of aortic valve. Results Velocity vector, vorticity and viscous shear stress were used to evaluate the effect of LVAD anastomosis angle on hemodynamics of aortic valve. During the period of rapid valve closure, with the increase of graft angle, the blood flow velocity near the valve wall, the average vorticity and the maximum viscous shear stress all increased. Conclusions When the graft angle is lower, the impact velocity of blood on the valve is smaller, and the shear force on the valve decreases, so that the valve is in a better hemodynamic environment. This study provides references for the selection of anastomotic angles in clinical operations.
ABSTRACT
Objective Aiming at the problems of lacking initiative in upper limb rehabilitation training equipment, single training mode, and low active participation of patients, an upper limb continuous motion estimation algorithm model based on multi-modal information fusion was proposed, so to realize accurate estimation of elbow joint torque. Methods Firstly, the surface electromyography (sEMG) signal and posture signal of participants were collected at four angular velocities, and the time domain characteristics of the signal were extracted. The principal component analysis was adopted to multi-feature fusion. The back propagation neural network (BPNN) was optimized through the additional momentum and the adaptive learning rate method. The particle swarm optimization (PSO) algorithm was used to optimize the neural network and a continuous motion estimation model based on PSO-BPNN was constructed. Finally, the joint torque calculated by the second type of Lagrangian equation was used as the accurate value to train the model. The performance of the model was compared with the traditional BP neural network model. Results The root mean square error (RMSE) of the traditional BP neural network model was 558.9 N·m, and the R2 coefficient was 77.19%, Whereas the RMSE and the R2 coefficient of the optimized model were 113.6 mN·m and 99.12%, respectively.Thereby, the accuracy of torque estimation was improved apparently. Conclusions The method for continuous motion estimation of the elbow joint proposed in this study can estimate the motion intention accurately, and provide a practical scheme for the active control of upper exoskeleton rehabilitation robot.
ABSTRACT
Objective:To explore the efficacy and safety of treating advanced esophageal cancer by implanting the common stent and the radioactive 125I particle stent with endoscope. Methods:The clinical data of patients with advanced esophageal cancer admitted to Jingbian County People's Hospital of Shaanxi Province, the First Affiliated Hospital of Xi'an Medical University, Xijing Hospital of Digestive Diseases of Air Force Medical University and the First Hospital of Yulin of Shaanxi Province from December 2014 to December 2020 were retrospectively analyzed. Patients were divided into common stent group ( n=66) and radioactive particle stent group ( n=34) according to different stent types. The postoperative complications, Karnofsky performance status (KPS) score, dysphagia score, restenosis rate and quality of life were compared between the two groups. Results:The incidences of postoperative retrosternal pain in the common stent group and the radioactive particle stent group were 65.2% (43/66) and 47.1% (16/34) respectively. The incidences of pharyngeal pain and hoarseness were 12.1% (8/66) and 5.9% (2/34) . The incidences of abdominal pain were 9.1% (6/66) and 2.9% (1/34) . The incidences of errhysis were 3.0% (2/66) and 2.9% (1/34) . The incidences of vomiting and nausea were 7.6% (5/66) and 5.9% (2/34) respectively. There were no statistically significant differences between the two groups ( χ2=3.04, P=0.081; χ2=0.40, P=0.527; χ2=0.53, P=0.467; χ2<0.01, P>0.999; χ2<0.01, P>0.999) . In the two groups, KPS scores in the first, second, third and sixth month after operation were higher than those before operation (all P<0.05) . KPS scores of the radioactive particle stent group in the second, third and sixth month were significantly higher than those of the common stent group [ (89.73±7.84) points vs. (82.37±7.42) points, t=4.62, P<0.001; (93.63±8.13) points vs. (88.33±7.28) points, t=3.74, P<0.001; (92.78±6.26) points vs. (87.28±8.73) points, t=3.77, P<0.001]. The dysphagia scores of patients in the two groups in the first, second, third and sixth month were lower than those before operation (all P<0.05) . The dysphagia scores of the radioactive particle stent group in the third and sixth month after operation were significantly lower than those of the common stent group [ (0.68±0.12) points vs. (2.33±0.32) points, t=26.20, P<0.001; (0.82±0.22) points vs. (2.67±0.24) points, t=36.92, P<0.001]. In the third month after operation, the restenosis rate of the radioactive particle stent group was significantly lower than that of the common stent group [5.88% (2/34) vs. 42.4% (28/66) , χ2 =14.27, P<0.001]. The scores of QLQ-C30 and OES-18 scales in the first, second, third and sixth month after operation were lower than those before operation (all P<0.05) . The scores of QLQ-30 scale in the radioactive particle stent group in the second, third and sixth month were significantly lower than those in the common stent group [ (19.12±3.02) points vs. (21.22±2.87) points, t=3.39, P=0.001; (15.04±1.68) points vs. (20.43±2.23) points, t=12.39, P<0.001; (14.38±2.18) points vs. (19.77±3.67) points, t=9.20, P<0.001]. The scores of OES-18 scale in the radioactive particle stent group were also significantly lower than those in the common stent group [ (17.13±2.07) points vs. (20.64±2.11) points, t=7.95, P<0.001; (15.22±1.88) points vs. (19.24±1.76) points, t=10.62, P<0.001; (14.74±2.36) points vs. (18.53±3.27) points, t=6.01, P<0.001]. Conclusion:The radioactive particle stent can improve the quality of life of patients with advanced esophageal cancer with esophageal stenosis, so as to improve dysphagia and reduce the restenosis rate after operation. However, whether it is obviously superior to common stent in prolonging survival time and reducing complications needs to be further confirmed by a multicenter, prospective, large-sample randomized controlled study.