The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,break...The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,breaking strength, breaking elongation and linear density of aerobic retted kenaf bundle fibers did not show significantly difference with that of anaerobic retted kenaf bundle fibers by ANOVA-Tukey's studentized test at a = 5% except for the softness. The bioenergetic principle and the calculation of the amount of ATP produced during the decomposition processing of kenaf gums were used to explain why the retting duration in the case of using aerobic microbes was much shorter than that of using anaerobic microbes.展开更多
Cultivable bacteria were isolated from seawater-based retting treatment of hemp, in which three of purified strains (SW- 1, SW- 2, and S-SW1) produced relatively high levels of pectinase activities, and also produced ...Cultivable bacteria were isolated from seawater-based retting treatment of hemp, in which three of purified strains (SW- 1, SW- 2, and S-SW1) produced relatively high levels of pectinase activities, and also produced mannanases and xylanases. PCR-based entebacterial repetitive intergenic consensus primers (ERIC-PCR) were employed for fingerprinting DNA of the bacterial strains. The ERIC-PCR fingerprints of stains SW- 1, SW- 2, and S-SW1 were found to be different, and should be further identified for each isolate. Strains SW- 1 and SW- 2 were identified as Stenotrophomnas maltophilia, while strain S-SW1 was assigned to Ochrobactrum anthropi by BIOLOG system. These two species represented rhizosphere bacterial genera, and possibly were introduced by the hemp plants. These organisms seemed potentially capable of producing pectinase and hemicellulase, and thus effectively degrading the gum substances in the seawater retting. This research could be helpful for improving a novel seawater-based retting treatment of hemp.展开更多
The upper and lower portions of Musa sapientum pseudo-stem sheaths were exposed in four types of treatments： pectin decomposing bacteria, magnesium oxide （MgO）, both pectin decomposing bacteria and MgO and control....The upper and lower portions of Musa sapientum pseudo-stem sheaths were exposed in four types of treatments： pectin decomposing bacteria, magnesium oxide （MgO）, both pectin decomposing bacteria and MgO and control. The fibre strength properties were tested using SIRIM Standard methods and colour changed using gray scale. The bioaugmentation of pectin decomposing bacteria together with MgO additions were found to enhance retting process and reduced retting periods 52% and yielded better strength on the fibres. The lower portion pseudo-stem sheaths gave the higher strength than upper portion. Colour changed showed that the bioaugmentation of pectin bacteria enhanced the degradation colouring compound in banana fibres.展开更多
The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the present study for treatment of flax retting wastewater. Batch and continuous experiments on a pilot scale were designed. The i...The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the present study for treatment of flax retting wastewater. Batch and continuous experiments on a pilot scale were designed. The initial seed for granules (bacteria acclimation) formed earlier was from municipal sewage treatment plant with VSS of 18 - 20 g/L. Batch experiments proved that the sludge retention time (SRT) was 77 days. Under steady state conditions, continuous experiments were conducted at organic loading rates (OLRs) in the range of 1.2 to8.6 kgCODs m–3·d–1, where the hy- draulic retention time (HRT) decreased from 72 to 12 hrs. The results proved that the UASB technology provides good COD removal efficiency from 64.5% to 90.5% as COD loading rate decreased and good biogas production at proper food: micro-organism (F:M) ratios.展开更多
Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for centuries.With its global abundance,banana pseudo-stem is a promising agro-waste for lignoce...Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for centuries.With its global abundance,banana pseudo-stem is a promising agro-waste for lignocellulosic fiber extraction.In this study,fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were conducted.Bacterial load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were analyzed.Fourier transform infrared(FT-IR)and X-day diffraction(XRD)analyses were also examined for both pre-treated and untreated extracted fibers.The results shows that six out of the eight bacterial isolates had the ability to degrade lignin.The treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded the highest viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on the 14th day of the retting process.Additionally,the highest laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in the second to the third week.The FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting conditions.The XRD diffractogram revealed that the crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment conditions.However,the CI for fibers pre-treated under enzymatic conditions were enhanced even after five weeks.Sequence analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis,Shewanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 strain.From these findings,it was suggested that physical,biological,and chemical actions were collectively involved in the seawater retting process of banana pseudo-stems.展开更多
BACKGROUND Multiple endocrine neoplasia type 2(MEN2)is a rare,autosomal dominant endocrine disease.Currently,the RET proto-oncogene is the only gene implicated in MEN2A pathogenesis.Once an RET carrier is detected,fam...BACKGROUND Multiple endocrine neoplasia type 2(MEN2)is a rare,autosomal dominant endocrine disease.Currently,the RET proto-oncogene is the only gene implicated in MEN2A pathogenesis.Once an RET carrier is detected,family members should be screened to enable early detection of medullary thyroid carcinoma,pheochromocytoma,and hyperparatitity.Among these,medullary thyroid carcinoma is the main factor responsible for patient mortality.Accordingly,delineating strategies to inform clinical follow-up and treatment plans based on genes is paramount for clinical practitioners.CASE SUMMARY Herein,we present RET proto-oncogene mutations,clinical characteristics,and treatment strategies in a family with MEN2A.A family study was conducted on patients diagnosed with MEN2A.DNA was extracted from the peripheral blood of family members,and first-generation exon sequencing of the RET protooncogene was conducted.The C634Y mutation was identified in three family members spanning three generations.Two patients were sequentially diagnosed with pheochromocytomas and bilateral medullary thyroid carcinomas.A 9-yearold child harboring the gene mutation was diagnosed with medullary thyroid carcinoma.Surgical resection of the tumors was performed.All family members were advised to undergo complete genetic testing related to the C634Y mutation,and the corresponding treatments administered based on test results and associated clinical guidelines.CONCLUSION Advancements in MEN2A research are important for familial management,assessment of medullary thyroid cancer invasive risk,and deciding surgical timing.展开更多
Volatile organic compounds(VOC)gas detection devices based on semiconductor sensors have become a common method due to their low cost,simple principle,and small size.However,with the continuous development of material...Volatile organic compounds(VOC)gas detection devices based on semiconductor sensors have become a common method due to their low cost,simple principle,and small size.However,with the continuous development of materials science,various new materials have been applied in the fabrication of gas sensors,but these new materials have more stringent requirements for operating temperature,which cannot be met by existing sensor modules on the market.Therefore,this paper proposes a temperature-adjustable sensor module and designs an environmental monitoring system based on the STM32F103RET6 microprocessor.This system primarily utilizes multiple semiconductor gas sensors to monitor and record the concentrations of various harmful gases in different environments.It can also monitor real-time temperature,humidity,and latitude and longitude in the current environment,and upload the data to the Internet of Things via 4G communication.This system has the advantages of small size,portability,and low cost.Experimental results show that the sensor module can achieve precise control of operating temperature to a certain extent,with an average temperature error of approximately 3%.The monitoring system demonstrates a certain level of accuracy in detecting target gases and can promptly upload the data to a cloud platform for storage and processing.A comparison with professional testing equipment shows that the sensitivity curves of each sensor exhibit similarity.This study provides engineering and technical references for the application of VOC gas sensors.展开更多
文摘The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,breaking strength, breaking elongation and linear density of aerobic retted kenaf bundle fibers did not show significantly difference with that of anaerobic retted kenaf bundle fibers by ANOVA-Tukey's studentized test at a = 5% except for the softness. The bioenergetic principle and the calculation of the amount of ATP produced during the decomposition processing of kenaf gums were used to explain why the retting duration in the case of using aerobic microbes was much shorter than that of using anaerobic microbes.
基金Programfor Changjiang Scholars and Innovative Research Teamin University,China( No .IRT0654)Major State Basic Research Development Program,China ( No .2008CB617506)Analysis and Test Foundation of Zhejiang Province,China ( No .2007F70040)
文摘Cultivable bacteria were isolated from seawater-based retting treatment of hemp, in which three of purified strains (SW- 1, SW- 2, and S-SW1) produced relatively high levels of pectinase activities, and also produced mannanases and xylanases. PCR-based entebacterial repetitive intergenic consensus primers (ERIC-PCR) were employed for fingerprinting DNA of the bacterial strains. The ERIC-PCR fingerprints of stains SW- 1, SW- 2, and S-SW1 were found to be different, and should be further identified for each isolate. Strains SW- 1 and SW- 2 were identified as Stenotrophomnas maltophilia, while strain S-SW1 was assigned to Ochrobactrum anthropi by BIOLOG system. These two species represented rhizosphere bacterial genera, and possibly were introduced by the hemp plants. These organisms seemed potentially capable of producing pectinase and hemicellulase, and thus effectively degrading the gum substances in the seawater retting. This research could be helpful for improving a novel seawater-based retting treatment of hemp.
文摘The upper and lower portions of Musa sapientum pseudo-stem sheaths were exposed in four types of treatments： pectin decomposing bacteria, magnesium oxide （MgO）, both pectin decomposing bacteria and MgO and control. The fibre strength properties were tested using SIRIM Standard methods and colour changed using gray scale. The bioaugmentation of pectin decomposing bacteria together with MgO additions were found to enhance retting process and reduced retting periods 52% and yielded better strength on the fibres. The lower portion pseudo-stem sheaths gave the higher strength than upper portion. Colour changed showed that the bioaugmentation of pectin bacteria enhanced the degradation colouring compound in banana fibres.
文摘The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the present study for treatment of flax retting wastewater. Batch and continuous experiments on a pilot scale were designed. The initial seed for granules (bacteria acclimation) formed earlier was from municipal sewage treatment plant with VSS of 18 - 20 g/L. Batch experiments proved that the sludge retention time (SRT) was 77 days. Under steady state conditions, continuous experiments were conducted at organic loading rates (OLRs) in the range of 1.2 to8.6 kgCODs m–3·d–1, where the hy- draulic retention time (HRT) decreased from 72 to 12 hrs. The results proved that the UASB technology provides good COD removal efficiency from 64.5% to 90.5% as COD loading rate decreased and good biogas production at proper food: micro-organism (F:M) ratios.
基金supported by the Science and Technology Development Fund(STDF)project(no.44049)and TICAD7 scholarship from the Egyptian and Japanese governments.We are also grateful to Professor Hiromi Nakanishi from the University of Tokyo,for the analyses with the PCR and TOYOBO for the sequencing.
文摘Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for centuries.With its global abundance,banana pseudo-stem is a promising agro-waste for lignocellulosic fiber extraction.In this study,fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were conducted.Bacterial load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were analyzed.Fourier transform infrared(FT-IR)and X-day diffraction(XRD)analyses were also examined for both pre-treated and untreated extracted fibers.The results shows that six out of the eight bacterial isolates had the ability to degrade lignin.The treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded the highest viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on the 14th day of the retting process.Additionally,the highest laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in the second to the third week.The FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting conditions.The XRD diffractogram revealed that the crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment conditions.However,the CI for fibers pre-treated under enzymatic conditions were enhanced even after five weeks.Sequence analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis,Shewanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 strain.From these findings,it was suggested that physical,biological,and chemical actions were collectively involved in the seawater retting process of banana pseudo-stems.
基金Supported by The Finance Bureau of Dongguan City,Guangdong Province.
文摘BACKGROUND Multiple endocrine neoplasia type 2(MEN2)is a rare,autosomal dominant endocrine disease.Currently,the RET proto-oncogene is the only gene implicated in MEN2A pathogenesis.Once an RET carrier is detected,family members should be screened to enable early detection of medullary thyroid carcinoma,pheochromocytoma,and hyperparatitity.Among these,medullary thyroid carcinoma is the main factor responsible for patient mortality.Accordingly,delineating strategies to inform clinical follow-up and treatment plans based on genes is paramount for clinical practitioners.CASE SUMMARY Herein,we present RET proto-oncogene mutations,clinical characteristics,and treatment strategies in a family with MEN2A.A family study was conducted on patients diagnosed with MEN2A.DNA was extracted from the peripheral blood of family members,and first-generation exon sequencing of the RET protooncogene was conducted.The C634Y mutation was identified in three family members spanning three generations.Two patients were sequentially diagnosed with pheochromocytomas and bilateral medullary thyroid carcinomas.A 9-yearold child harboring the gene mutation was diagnosed with medullary thyroid carcinoma.Surgical resection of the tumors was performed.All family members were advised to undergo complete genetic testing related to the C634Y mutation,and the corresponding treatments administered based on test results and associated clinical guidelines.CONCLUSION Advancements in MEN2A research are important for familial management,assessment of medullary thyroid cancer invasive risk,and deciding surgical timing.
文摘Volatile organic compounds(VOC)gas detection devices based on semiconductor sensors have become a common method due to their low cost,simple principle,and small size.However,with the continuous development of materials science,various new materials have been applied in the fabrication of gas sensors,but these new materials have more stringent requirements for operating temperature,which cannot be met by existing sensor modules on the market.Therefore,this paper proposes a temperature-adjustable sensor module and designs an environmental monitoring system based on the STM32F103RET6 microprocessor.This system primarily utilizes multiple semiconductor gas sensors to monitor and record the concentrations of various harmful gases in different environments.It can also monitor real-time temperature,humidity,and latitude and longitude in the current environment,and upload the data to the Internet of Things via 4G communication.This system has the advantages of small size,portability,and low cost.Experimental results show that the sensor module can achieve precise control of operating temperature to a certain extent,with an average temperature error of approximately 3%.The monitoring system demonstrates a certain level of accuracy in detecting target gases and can promptly upload the data to a cloud platform for storage and processing.A comparison with professional testing equipment shows that the sensitivity curves of each sensor exhibit similarity.This study provides engineering and technical references for the application of VOC gas sensors.
