PCR-DGGE Analysis of Bacterial Communities Structure in Babylonia areolata Culture Systems of The Subtidal Zone and The Pond Mulched Plastic Film and Sand in Bottom

To know the bacterial communities structure in Babylonia areolata culture systems and to research and optimize the management pattem of Babylonia areola-ta culture systems of the pond mulched plastic film and sand in bottom, the bacte- rial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom were analyzed at molecular level by adopting the denaturing gradient gel electrophoresis （DGGE）. The results indicated that the dominant bacterial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom, which were built on the basis of the seawater in East-island of Zhanjiang, included Proteobac- teda Chloroflexi, Cyanobacteria and Actinobacteria. The dominant bacterial groups in the above pond culture system were Garnmaproteobacteria, Alphaproteobacteria, Deltaprotecbacteda, Epsilonproteobacteda, Anaerolineae, Cyanobacteria and Acti- nobacteda. The dominant bacterial communities in the subtidal zone culture system were Gammaprotecbacteda, Alphaproteobacteria, Deltaproteobacteria, Anaerolineae and Cyanobacteda, and there were less Epsilonproteobacteria and Actinobacteria in the culture system. The higher diversity was detected in the above two culture sys- tems. The results of unweighted pair group method with arithmetic average （UPG- MA） showed that the bacterial communities of the sediment samples S1 and S2 in the above two culture systems were a cluster, the similarity of bacterial communities was 54.5%. The bacterial communities of seawater samples S3 and S4 in the above culture systems were in clusters, and the similarity of the bacterial communi- ties was 84.0%. The results showed that the microorganism ecological level in the Babylonia areolata culture systems of the pond mulched plastic film and sand in bottom could be similar to the sub-tidal zone culture systems through changing the pond seawater and monitoring the microbial population.

Spatial distribution characteristics of bacterial community structure and gene abundance in sediments of the Bohai Sea

This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were used to assay the bacterial 16S rRNA genes in the surface sediments of 13 sampling stations in the Bohai Sea.The results showed that sediments at the majority of the 13 sampling stations were contaminated by heavy metal mercury.The main phyla of bacteria recorded included Proteobacteria(52.92%),Bacteroidetes(11.76%),Planctomycetes(7.39%),Acidobacteria(6.53%)and Chloroflexi(4.97%).The genus with the highest relative abundance was Desulfobulbus(4.99%),which was the dominant genus at most sampling stations,followed by Lutimonas and Halioglobus.The main factors influencing bacterial community structure were total organic carbon,followed by depth and total phosphorus.The content of lead,cadmium,chromium,copper and zinc had a consistent effect on community structure.Arsenic showed a negative correlation with bacterial community structure in most samples,while the impact of mercury on community structure was not significant.The bacterial community in sediment samples from the Bohai Sea was rich in diversity and displayed an increase in diversity from high to low latitudes.The data indicated that the Bohai Sea had abundant microbial resources and was rich in bacteria with the potential to metabolize many types of pollutants.

Bacterial diversity and community structure in the East China Sea by 454 sequencing of the 16S rRNA gene

The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater samples and fi ve sediment samples sourced in May 2011. A total of 22 phyla, 34 classes, 74 orders, 146 families, and 333 genera were identifi ed in this study. Some of them were detected for the fi rst time from the East China Sea. The estimated richness and diversity indices were both higher in the sediment samples compared with in the seawater samples. All the samples were divided by their diversity indices into four regions. Similarity analysis showed that the seawater samples could be classifi ed into six groups. The groups differed from each other and had unique community structure characteristics. It was found that different water masses in the sampling areas may have had some infl uence on the bacterial community structure. A canonical correspondence analysis revealed that seawater samples in different areas and at different depths were affected by different environmental parameters. This study will lay the foundation for future research on microbiology in the East China Sea.

Degradation Characteristics and Community Structure of a Hydrocarbon Degrading Bacterial Consortium

A hydrocarbon degrading bacterial consortium KO5-2 was isolated from oil-contaminated soil of Karamay in Xinjiang, China, which could remove 56.9% of 10 g/L total petroleum hydrocarbons(TPH) at 30 ℃ after 7 days of incubation, and could also remove 100% of fluorene, 98.93% of phenanthrene and 65.73% of pyrene within 3, 7 and 9 days, respectively. Twelve strains from six different genera were isolated from KO5-2 and only eight ones were able to utilize the TPH. The denaturing gradient gel electrophoresis(DGGE) was used to investigate the microbial community shifts in five different carbon sources(including TPH, saturated hydrocarbons, fluorene, phenanthrene and pyrene). The test results indicated that the community compositions of KO5-2 in carbon sources of TPH and saturated hydrocarbons, respectively, were roughly the same, while they were distinctive in the three different carbon sources of PAHs. Rhodococcus sp. and Pseudomonas sp. could survive in the five kinds of carbon sources. Bacillus sp., Sphingomonas sp. and Ochrobactrum sp. likely played key roles in the degradation of saturated hydrocarbons, PAHs and phenanthrene, respectively. This study showed that specific bacterial phylotypes were associated with different contaminants and complex interactions between bacterial species, and the medium conditions influenced the biodegradation capacity of the microbial communities involved in bioremediation processes.

Effects of enrichmemt planting with native tree species on bacterial community structure and potential impact on Eucalyptus plantations in southern China

Multi-generational planting of Eucalyptus species degrades soil quality but the introduction of legumes can improve soil fertility and microbial diversity.However,the effects of introducing non-legume native tree species on soil nutrients and bacterial community structure remain poorly understood.This study investigated the impacts of the conversion of third generation monoculture Eucalyptus plantations to mixed systems including Eucalyptus urograndis with Cinnamomum camphora(EC)and E.urograndis with Castanopsis hystrix(EH),on soil chemical and biochemical properties and bacterial community structure,diversity and functions.First generation E.urophylla plantations were the control.Results show that planting the third generation Eucalyptus led to a significant decrease in p H,organic matter,nutrient content,enzyme activities(invertin,acid phosphataes,and urease),and bacterialα-diversity compare to the controls.However,the mixed planting showed significant improvement in soil chemical and biochemical attributes and bacterialα-diversity,although the E.urograndis and C.hystrix planting had no improvement.Chloroflexi(oligotrophic bacteria)were significantly enriched in third generation Eucalyptus and Eucalyptus+C.hystrix,while proteobacteria increased significantly in the E.urograndis with C.camphora plantings.The relative abundance of multiple metabolic pathways increased significantly in the third generation Eucalyptus plantations whereas membrane transportrelated genes were enriched in soils of the mixed systems.The changes in bacterial community structures in the two mixed systems were driven by diversity,organic matter and acid phosphatase,while bacterial functions were affected by invertase,NO_(3)^(-)-N,diversity and urease.These results suggest that the transformation of successive monoculture Eucalyptus plantations into mixed plantations reduces the depletion of soil nutrients and enhances the ecological function of soil microorganisms.

Wheat, maize and sunflower cropping systems selectively influence bacteria community structure and diversity in their and succeeding crop's rhizosphere

supported by the Special Fund for Agro-scientific Research in the Public Interest in China （201103001）

Bacterial Cellulose/Zwitterionic Dual-network Porous Gel Polymer Electrolytes with High Ionic Conductivity

Bacterial cellulose(BC)was innovatively combined with zwitterionic copolymer acrylamide and sulfobetaine methacrylic acid ester[P(AM-co-SBMA)]to build a dual-network porous structure gel polymer electrolytes(GPEs)with high ionic conductivity.The dual network structure BC/P(AM-co-SBMA)gels were formed by a simple one-step polymerization method.The results show that ionic conductivity of BC/P(AM-co-SBMA)GPEs at the room temperature are 3.2×10^(-2) S/cm@1 M H_(2)SO_(4),4.5×10^(-2) S/cm@4 M KOH,and 3.6×10^(-2) S/cm@1 M NaCl,respectively.Using active carbon(AC)as the electrodes,BC/P(AM-co-SBMA)GPEs as both separator and electrolyte matrix,and 4 M KOH as the electrolyte,a symmetric solid supercapacitors(SSC)(AC-GPE-KOH)was assembled and testified.The specific capacitance of AC electrode is 173 F/g and remains 95.0%of the initial value after 5000 cycles and 86.2%after 10,000 cycles.

Rapid bacteria identification using structured illumination microscopy and machine learning

Traditionally,optical microscopy is used to visualize the morphological features of pathogenic bacteria,of which the features are further used for the detection and ident ification of the bacteria.However,due to the resolution limitation of conventional optical microscopy as well as the lack of standard pattern library for bacteria identification,the ffectiveness of this optical microscopy-based method is limited.Here,we reported a pilot study on a combined use of Structured Illumination Microscopy(SIM)with machine learning for rapid bacteria identification.After applying machine learning to the SIM image datasets from three model bacteria(including Escherichia coli,Mycobacterium smegmatis,and Pseudomonas aeruginosa),we obtained a classifcation accuracy of up to 98%.This study points out a promising possibility for rapid bacterial identification by morphological features.

BACTERIAL CELLULOSE AS A BASE MATERIAL IN BIODIGITAL ARCHITECTURE(BETWEEN BIO-MATERIAL DEVELOPMENT AND STRUCTURAL CUSTOMIZATION)

1.ABSTRACT Recently,developing sustainable architectural materials from renewable resources is gaining great interest.This interest is intended to alleviate the drawbacks of petro-leum-based materials and their contribution in the escalation of CO_(2) emissions causing the current environmental deterioration.Achieving sustainability through developing efficient architectural materials have been always conditioned by tech-nological advancements and economic potential.This has affected the architectural design and construction sectors,especially in times of disasters or economic crisis,resulting in paralysis in the architectural construction and material development.These effects were caused by the capitalization and centralization of architectural construction industries.The recent trend of self-sufficiency that had first emerged in environmental activities supporting recycling,environmental purification and conservation,oxygen,food,and electricity production,has extended to cover more sophisticated products,such as wearables,gadgets and architecture.Achieving self-sufficiency in architecture is of interest to multidisciplinary researchers who focus on developing both self-suf-ficient systems and materials as the two main components of the built environment.Developing architectural materials aims to provide cheap,recycled,renewable,environmentally friendly,durable and sustainable building material regardless of the possibility of the autonomous production of these materials on a popular democratic basis.Architectural building materials production was always and still is consid-ered a massive industry that is centralized in major firms and LTDs,limiting the architectural construction process to the availability of major economic capacity.This centralization had its merits in forcing forward large-scale economies and vital-izing the architectural design and construction market,but only on the large scale;however,this centralization shows its drawbacks every time in disasters or economic crisis,causing almost total paralysis in the construction industry due to economic impotence caused by different reasons.Moreover,the centralization of the building and construction industry have affected developing communities,causing economic drawbacks and creating a ripple-like crisis in housing.In this paper,the authors propose the self-sufficiency approach in the develop-ment and production of sustainable architectural material from abundant and renew-able microbial agents,in order to democratize and popularize material production on a domestic and personalized basis.The current work presents Bacterial Cellulose(BC)as a structural and mem-brane material in different architectural elements and applications,developed through simple and domestically applied procedures in order to create distributed and self-sufficient productive units for architectural materials production.The current study aims specifically at the easiness and simplification of the pro-duction practices and procedures of the biopolymers,and specifically bacterial cellu-lose for encouraging and establishing the popularization of self-sufficient production units of these renewable and abundant biopolymers.In this regard,the current study is part of the ongoing research on enhancing the mechanical properties of bacterial cellulose in order to use it for structural applications,that will be further developed in terms of medium optimization,bacterial cellulose production efficiency analysis,and material mechanical and physical properties testing.The following sections will contain a literature review on the chemical base and physical/mechanical properties of biopolymers including bacterial cellulose,followed by the experimental work conducted in this paper to develop bacterial cellulose as an architectural material.The results were further analyzed through formal and struc-tural customization proposing possible applications in architectural design.

Dynamic changes in microbial activity and community structure during biodegradation of petroleum compounds:A laboratory experiment

With 110-d incubation experiment in laboratory, the responses of microbial quantity, soil enzymatic activity, and bacterial community structure to different amounts of diesel fuel amendments were studied to reveal whether certain biological and biochemical characteristics could serve as reliable indicators of petroleum hydrocarbon contamination in meadow-brown soil, and use these indicators to evaluate the actual ecological impacts of 50-year petroleum-refining wastewater irrigation on soil function in Shenfu irrigation area. Results showed that amendments of ~ 1000 mg/kg diesel fuel stimulated the growth of aerobic heterotrophic bacteria, and increased the activity of soil dehydrogenase, hydrogenperoxidase, polyphenol oxidase and substrate-induced respiration. Soil bacterial diversity decreased slightly during the first 15 d of incubation and recovered to the control level on day 30. The significant decrease of the colony forming units of soil actinomyces and filamentous fungi can be taken as the sensitive biological indicators of petroleum contamination when soil was amended with 〉15000 mg/kg diesel fuel. The sharp decrease in urease activity was recommended as the most sensitive biochemical indicator of heavy diesel fuel contamination. The shifts in community structure to a community documented by Sphingomonadaceae within a-subgroup of Proteobacteria could be served as a sensitive and precise indicator of diesel fuel contamination. Based on the results described in this paper, the soil function in Shenfu irrigation area was disturbed to some extent.

Inclusion of peanut in wheat–maize rotation increases wheat yield and net return and improves soil organic carbon pool by optimizing bacterial community

Improving soil quality while achieving higher productivity is the major challenge in the agricultural industry. Wheat(Triticum aestivum L.)–maize(Zea mays L.)(W–M) rotation is the dominant planting pattern in the Huang-HuaiHai Plain and is important for food security in China. However, the soil quality is deteriorating due to the W–M rotation’s long-term, intensive, and continuous cultivation. Introducing legumes into the W–M rotation system may be an effective way to improve soil quality. In this study, we aimed to verify this hypothesis by exploring efficient planting systems(wheat–peanut(Arachis hypogaea L.)(W–P) rotation and wheat rotated with maize and peanut intercropping(W–M/P)) to achieve higher agricultural production in the Huang-Huai-Hai Plain. Using traditional W–M rotation as the control, we evaluated crop productivity, net returns, soil microorganisms(SMs), and soil organic carbon(SOC) fractions for three consecutive years. The results indicated that wheat yields were significantly increased under W–P and W–M/P(382.5–579.0 and 179.8–513.1 kg ha-1, respectively) compared with W–M. W–P and W–M/P provided significantly higher net returns(58.2 and 70.4%, respectively) than W–M. W–M/P and W–M retained the SOC stock more efficiently than W–P, increasing by 25.46–31.03 and 14.47–27.64%, respectively, in the 0–20 cm soil layer. Compared with W–M, W–M/P improved labile carbon fractions;the sensitivity index of potentially mineralizable carbon, microbial biomass carbon(MBC), and dissolved organic carbon was 31.5, 96.5–157.2, and 17.8% in 20–40, 10–40, and 10–20 cm soil layers, respectively. The bacterial community composition and bacteria function were altered as per the soil depth and planting pattern. W–M/P and W–M exhibited similar bacterial community composition and function in 0–20 and 20–40 cm soil layers. Compared with W–P, a higher abundance of functional genes, namely, contains mobile elements and stress-tolerant, and a lower abundance of genes, namely,potentially pathogenic, were observed in the 10–20 cm soil layer of W–M and the 0–20 cm soil layer of W–M/P. SOC and MBC were the main factors affecting soil bacterial communities, positively correlated with Sphingomonadales and Gemmatimonadales and negatively correlated with Blastocatellales. Organic input was the main factor affecting SOC and SMs, which exhibited feedback effects on crop productivity. In summary, W–M/P improved productivity, net returns, and SOC pool compared with traditional W–M rotation systems, and it is recommended that plant–soil–microbial interactions be considered while designing high-yield cropping systems.

Temporal and spatial variations of bacterial community compositions in two estuaries of Chaohu Lake

The distinctive estuary hydrodynamics and nutrient input make the estuary ecosystem play a key role in lake ecosystems.The Nanfei River and Zhaohe River are two main inlets of Chaohu Lake,Anhui,East China.We selected estuaries of the two rivers as representative areas to study temporal and spatial changes of bacterial communities.In August(summer)and November(autumn)2016 and February(winter)and May(spring)2017,16 water and sediment samples were collected from the estuaries.Physicochemical characteristics indicate significant differences in the nutritional status and eutrophication index of the estuaries due mainly to organic input.Examination of the number of operational taxonomic units,the diversity index,the community composition,and redundancy analysis revealed the following.First,the existence of varying degrees of seasonal differences in the distribution of almost all bacteria.In addition,the species diversity in the sediment samples was higher than that in the water samples,and the dominant species differed also among these samples.Second,a large number of unknown genera were detected,especially in the sediment samples,such as unclassified Xanthomonadales incertae sedis,unclassified Anaerolineaceae,and unclassified Alcaligenaceae.Last,TP,TN,and TOC were the main influential factors that affected the bacterial community structure.

Bacterial community succession in response to dissolved organic matter released from live jellyfish

Jellyfish blooms have increased worldwide, and the outbreaks of jellyfish population not only affect the food web structures via voracious predation but also play an important role in the dynamics of nutrients and oxygen in planktonic food webs. However, it remains unclear whether specific carbon compounds released through jellyfish metabolic processes have the potential to shape bacterial community composition. Therefore, in this study, we aimed to investigate the compositional succession of the bacterioplankton community in response to the dissolved organic matter (DOM) released by the live Scyphomedusae Cyanea lamarckii and Chrysaora hysoscella collected from Helgoland Roads of the North Sea. The bacterial community was significantly stimulated by the DOM released form live jellyfish and different dominant phylotypes were observed for these two Scyphomedusae species. Furthermore, the bacterial community structures in the different DOM sources, jellyfish-incubated media, Kabeltonne seawater, and artificial seawater (DOM-free) were significantly different, as revealed by automated ribosomal intergenic spacer analysis fingerprints. Catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) revealed a rapid species-specific shift in bacterial community composition. Gammaproteobacteria dominated the community instead of the Bacteroidetes community for C. lamarckii, whereas Gammaproteobacteria and Bacteroidetes dominated the community for C. hysoscella. The significant differences in the bacterial community composition and succession indicate that the components of the DOM released by jellyfish might differ with jellyfish species.

Variation of bacterial community associated with Phaeodactylum tricornutum in response to different inorganic nitrogen concentrations

Specific bacterial communities interact with phytoplankton in laboratory algal cultures. These communities influence phytoplankton physiology and metabolism by transforming and exchanging phytoplankton-derived organic matter. Functional bacterial groups may participate in various critical nutrients fluxes within these associations, including nitrogen(N) metabolism. However, it is unclear how bacterial communities and the associated algae respond to changes of phycosphere N conditions. This response may have far-reaching implications for global nutrient cycling, algal bloom formation, and ecosystem function. Here, we identified changes in the bacterial communities associated with Phaeodactylum tricornutum when co-cultured with different forms and concentrations of N based on the Illumina HiSeq sequencing of 16 S rRNA amplicons.Phylogenetic analysis identified Proteobacteria and Bacteroidetes as the dominant phyla, accounting for 99.5% of all sequences. Importantly, bacterial abundance and community structure were more affected by algal abundance than by the form or concentration of inorganic N. The relative abundance of three gammaproteobacterial genera(Marinobacter, Algiphilus and Methylophaga) markedly increased in N-deficient cultures. Thus, some bacterial groups may play a role in the regulation of N metabolism when co-cultured with P.tricornutum.

Bacterial entombment by intratubular mineralization following orthograde mineral trioxide aggregate obturation: a scanning electron microscopy study

The time domain entombment of bacteria by intratubular mineralization following orthograde canal obturation with mineral trioxide aggregate（MTA） was studied by scanning electron microscopy（SEM）. Single-rooted human premolars（n560） were instrumented to an apical size #50/0.06 using ProF ile and treated as follows： Group 1（n510） was filled with phosphate buffered saline（PBS）; Group 2（n510） was incubated with Enterococcus faecalis for 3 weeks, and then filled with PBS; Group 3（n520） was obturated orthograde with a paste of OrthoM TA（BioM TA, Seoul, Korea） and PBS; and Group 4（n520） was incubated with E. faecalis for 3 weeks and then obturated with OrthoM TA–PBS paste. Following their treatments, the coronal openings were sealed with PBS-soaked cotton and intermediate restorative material（IRM）, and the roots were then stored in PBS for 1, 2, 4, 8 or 16 weeks. After each incubation period, the roots were split and their dentin/MTA interfaces examined in both longitudinal and horizontal directions by SEM. There appeared to be an increase in intratubular mineralization over time in the OrthoM TA-filled roots（Groups 3 and 4）. Furthermore, there was a gradual entombment of bacteria within the dentinal tubules in the E. faecalis inoculated MTA-filled roots（Group 4）. Therefore, the orthograde obturation of root canals with OrthoM TA mixed with PBS may create a favorable environment for bacterial entombment by intratubular mineralization.

Benthic bacterial communities indicate anthropogenic activity footprints in coastal area under long-term marine spatial planning practice

Marine spatial planning(MSP)is designed to divide the sea area into different types of functional zones,to implement corresponding development activities.However,the long-term impacts of anthropogenic activities associated with MSP practice on the marine microbial biosphere are still unclear.Yalu River Estuary,a coastal region in northeast of China,has been divided into fishery&agricultural(F&A)zone,shipping&port(S&P)zone and marine protected area(MPA)zone by a local MSP guideline that has been run for decades.To examine the effects of long-term executed MSP,benthic bacterial communities from different MSP zones were obtained and compared in this study.The results revealed significant differences in the bacterial community structure and predict functions among different zones.Bacterial genera enriched in different zones were identified,including SBR1031 in MPA,Woeseia and Sva0996 in S&P,and Halioglobus in F&A.In addition,correlations between some bacterial genera and sediment pollutants were uncovered.Furthermore,bacteria related to sulphide production were more abundant in the F&A zone,which was according to the accumulation of sulphides in this area.Moreover,bacteria associated with chemoheterotrophy and fermentation were more predominant in the S&P zone,consistent with high levels of organic matter and petroleum caused by shipping.Our findings indicated benthic bacterial communities could bring to light the anthropogenic activity footprints by different activities induced by long-term MSP practice.

Soil bacterial characteristics between surface and subsurface soils along a precipitation gradient in the Alxa Desert, China

Bacteria in desert soil have unique phylogeny and important ecological functions, and theirresponses to changes in precipitation need further attention. However, relevant studies have mainlyfocused on the surface soil, and studies on the responses of bacteria at different soil depths to variationsin precipitation are rare. Thus, we used 16S rDNA high-throughput sequencing to investigate the changesin soil bacterial distribution along a mean annual precipitation gradient (50–150 mm) in the Alxa Desert,China, and compared the variation characteristics in the surface soil layer (0–10 cm) and subsurface soillayer (10–20 cm). Results showed that soil bacterial communities significantly changed along theprecipitation gradient in both soil layers. However, the subsurface soil layer could support bacterialcommunities with higher diversity and closer internal relationships but more internal competition than thesurface soil layer. Additionally, compared with the surface soil layer, variations in diversity andco-occurrence patterns in the subsurface soil layer were more in line with the changes in the mean annualprecipitation, while bacterial community structure was less variable in the subsurface soil layer. Comparedwith the mean annual precipitation, soil moisture had little influence on the structure and diversity of soilbacterial community but had a high correlation with intercommunity connectivity. Therefore, soilmoisture might play a complex role in mediating environmental conditions and soil bacterial communitycharacteristics. Due to the different responses of surface and subsurface soil bacteria to the changes inprecipitation, it is necessary to distinguish different soil layers when predicting the trends in desert soilbacterial conditions associated with precipitation, and prediction of subsurface soil bacteria may be moreaccurate.

Hierarchical Structured Fabrics with Enhanced Pressure Sensing Performance Based on Orientated Growth of Functional Bacterial Cellulose

Wearable electronics based on natural biomaterials,such as bacterial cellulose(BC),have shown promise for a variety of healthcare and human-computer interaction applications.However,current BC-based pressure sensors have an inherent limi-tation,which is the two-dimensional rigid structures and limited compressibility of BC restrict the sensitivity and working range for pressure sensing.Here,we propose a strategy for fabricating BC/polypyrrole/spacer fabric(BPSF)pressure sensors with a hierarchical structure constructed by integrating conductive BC nanonetwork into a compressible fabric frame via the in situ biofermentation process.The hierarchical structure design includes a cross-scale network from the nanoscale BC sensor networks to the macroscopic three-dimensional compressible fabric sensor network,which significantly improves the working range(0-300 kPa)and sensitivity(40.62 kPa-1)of BPSF.Via this unique structural design,the sensor also achieves a high fatigue life(~5000 cycles),wearability,and reproducibility even after several washing and abrasion cycles.Furthermore,a flexible and wearable electronic textile featuring an n×n sensing matrix was developed by constructing BPSF arrays,allowing for the precise control of machines and weight distribution analysis.These empirical insights are valuable for the biofabrication and textile structure design of wearable devices toward the realization of highly intuitive human-machine interfaces.

Screening and degrading characteristics and community structure of a high molecular weight polycyclic aromatic hydrocarbon-degrading bacterial consortium from contaminated soil

Inoculation with efficient microbes had been proved to be the most important way for the bioremediation of polluted environments. For the treatment of abandoned site of Beijing Coking Chemical Plant contaminated with high level of high-molecular-weight polycyclic aromatic hydrocarbons （HMW-PAHs）, a bacterial consortium capable of degrading HMW-PAHs, designated 1-18-1, was enriched and screened from HMW-PAHs contaminated soil. Its degrading ability was analyzed by high performance liquid chromatography （HPLC）, and the community structure was investigated by construction and analyses of the 16S rRNA gene clone libraries （A, B and F） at different transfers. The results indicated that 1-18-1 was able to utilize pyrene, fluoranthene and benzo[a]pyrene as sole carbon and energy source for growth. The degradation rate of pyrene and fluoranthene reached 82.8% and 96.2% after incubation for 8 days at 30℃, respectively; while the degradation rate of benzo[a]pyrene was only 65.1% after incubation for 28 days at 30℃. Totally, 108, 100 and 100 valid clones were randomly selected and sequenced from the libraries A, B, and E Phylogenetic analyses showed that all the clones could be divided into 5 groups, Bacteroidetes, ct-Proteobacteria, Actinobacteria, β-Proteobacteda and γ- Proteobacteria. Sequence similarity analyses showed total 39 operational taxonomic units （OTUs） in the libraries. The predominant bacterial groups were α-Proteobacteria （19 OTUs, 48.7%）, γ-Proteobacteria （90TUs, 23.1%） and β-Proteobacteria （80TUs, 20.5%）. During the transfer process, the proportions of α-Proteobacteria and β-Proteobacteria increased greatly （from 47% to 93%）, while γ-Proteobacteda decreased from 32% （library A） to 6% （library F）; and Bacteroidetes group disappeared in libraries B and F.

Effects of carbon sources and temperature on the formation and structural characteristics of food-related Staphylococcus epidermidis biofilms

Biofilms are a constant concern in the food industry;understanding the effect of environmental conditions on biofilm formation is essential to develop effective control strategies.Therefore,this study was conducted to investigate biofilms formation by Staphylococcus epidermidis under various conditions.Biofilms were cultured in nutrient broth containing different carbon source concentrations(0–10 mg/mL)on polystyrene surfaces for 32 h of incubation at 37℃or 55℃,with quantification and enumeration at 8,16,24 and 32 h.S.epidermidis developed biofilms under all tested conditions;achieved the highest yield of biofilm biomass at 2.5 mg/mL for all carbon sources at 37℃.The highest efficiency of extracellular polymeric substance(EPS)molecule production occurred under glucose availability in the growth environment,with a higher yield of biomass and a significantly smaller number of metabolically active cells than under other tested conditions.A condensed ball-shaped structure was observed under the lactose condition.Meanwhile,biofilms in the presence of maltose showed mainly opaque thick rich colonies,while a compact multilayered-shaped structure was exhibited under both glucose and sucrose conditions.These results contribute to a better understanding of the biofilm formation by S.epidermidis in order to reduce contamination and recontamination in the food industry.