Numerical simulation of wrinkle morphology formation and the evolution of different Bacillus subtilis biofilms

2015 ◽  
Vol 73 (3) ◽  
pp. 527-534 ◽  
Author(s):  
Xiaoling Wang ◽  
Mudong Hao ◽  
Guoqing Wang
Keyword(s):  
Mechanical Properties ◽  
Bacillus Subtilis ◽  
Mechanical Model ◽  
Quantitative Relationship ◽  
Finite Element Software ◽  
Model And Simulation ◽  
Agar Substrate ◽  
Set Up ◽  
And Control ◽  
Number Of Bacteria

Wrinkle morphology is a distinctive phenomenon observed in mature biofilms that are produced by a great number of bacteria. The wrinkle pattern depends on the mechanical properties of the agar substrate and the biofilm itself, governed by the extracellular matrix (ECM). Here we study the macroscopic structures and the evolution of Bacillus subtilis biofilm wrinkles using the commercial finite element software ABAQUS. A mechanical model and simulation are set up to analyze and evaluate bacteria biofilm's wrinkle characteristics. We uncover the wrinkle formation mechanism and enumerate the quantitative relationship between wrinkle structure and mechanical properties of biofilm and its substrate. Our work can be used to modify the wrinkle pattern and control the biofilm size.

Mechanical Model and Analysis on Movement of Rock Strata between Coal Seams in Pillar Upward Mining of Left-Over Coal

2011 ◽  
Vol 58-60 ◽  
pp. 393-398
Author(s):  
Guo Rui Feng ◽  
Jing Zheng ◽  
Ya Feng Ren ◽  
Cong Ming Zhong ◽  
Li Xun Kang
Keyword(s):  
Differential Equation ◽  
Mechanical Properties ◽  
Partial Differential Equation ◽  
Mechanical Model ◽  
Theoretical Foundation ◽  
Control Measures ◽  
Coal Seams ◽  
Set Up ◽  
Rock Strata ◽  
Upward Mining

Work out control measures for pillar upward mining of left-over coal, in view of coal floor movement, this paper analyzes theoretical foundation and mechanical properties of mechanical model on coal floor movement of rock strata between coal seams in pillar upward mining of left-over coal and presents a simplified corresponding mechanical condition. Taking into the relation between layer movement and time consideration, the PTh model is used to show its rheological properties. By using a two-dimension model, mechanical model of coal floor movement is set up and both ends of cantilever beam are fixed. Finally, subsiding partial differential equation is induced at different districts in pillar upward mining of left-over coal. After solving the equation, prediction model about law of coal floor movement at different districts is gotten in pillar upward mining of left-over coal, which provides a theory basis for further study on upward mining.

Effect of Bacillus subtilis on Meloidogyne javanica and on Tomato Growth Promotion

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Elisete Pedreira Lopes ◽  
Regina Cássia Ferreira Ribeiro ◽  
Adelica Aparecida Xavier ◽  
Renato Martins Alves ◽  
Marcelly Thais de Castro ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Growth Promotion ◽  
Statistical Design ◽  
Meloidogyne Javanica ◽  
Root Mass ◽  
Tomato Growth ◽  
Set Up ◽  
Shoot Mass ◽  
And Control ◽  
Fresh Root

Objective: To evaluate under controlled conditions the effect of alternative liquid Bacillus subtilis isolate 34 formulation on Meloidogyne javanica and tomato growth promotion. Statistical Design: The design was completely randomized block with five treatments and eight replicates. The results were submitted to the analysis of variance and the averages compared by the Tukey test with 5% error probability. The statistical package used in the analysis of the data was the program "Sisvar" Location and Duration of the Experiment: The experiment was set up during the period from February 13, 2018 to April 20, 2018 in greenhouse located at the State University of Montes Claros, municipality of Janaúba, MG, Brazil. Methods: Treatments consisted of different times of application of bacteria in tomato seedlings: application of bacteria in the tube at eight and fifteen days after emergence; application of bacteria in the tube at eight and fifteen days after emergence and in pots at 25 and 35 days after transplanting; application of bacteria at 25 and 35 days after transplantation in the pot; Onix® commercial product (Bacillus methylotrophicus-UFPEDA20) and control. After 60 days of transplanting, the number of egg masses, number of galls, number of eggs, number of second-stage juveniles (J2) and reproduction factor, height, fresh and dry shoot mass and fresh root mass of tomato plants were evaluated. Results: There was a reduction in the number of J2, eggs pre root, and eggs per gram of root when the bacteria formulation was applied in the tube + pot and in pot only. The application of the bacteria in the tube + pot and in only pot only presents the highest increase of fresh and dry shoot mass and fresh root mass. Conclusion: The application of the liquid B. subtilis isolated 34 formulation to the soil in the pot and tube + pot reduced the reproduction of M. javanica and promoted greater tomato development.

Dynamic Analysis of Stiffness Part for a Electromagnetic High Frequency Fatigue Testing Machine

2014 ◽  
Vol 983 ◽  
pp. 194-197
Author(s):  
Yan Zheng ◽  
Yong Zhang ◽  
Xiao Wang Fan
Keyword(s):  
Mechanical Properties ◽  
Complex Systems ◽  
Dynamic Analysis ◽  
High Frequency ◽  
Mechanical Model ◽  
Design Principle ◽  
Theoretical Foundation ◽  
Fatigue Testing ◽  
Testing Machine ◽  
Set Up

Aiming at the problem that complex systems mechanical model is difficult to set up and analyze accurately, a certain type of electromagnetic high frequency fatigue tester as engineering background, setting up its mechanical model and carrying on the reasonable simplified. Through analyzing the effect of system mechanical properties causing by system main large stiffness parts, and determining the design principle of the engine's stiffness components, it provides scientific theoretical foundation for the design of this type host.

Pittenweem Priory and the conventuality question

2017 ◽  
Vol 68 (1) ◽  
pp. 19-37 ◽  
Author(s):  
Anthony Lodge
Keyword(s):  
Fifteenth Century ◽  
Traditional View ◽  
Archaeological Evidence ◽  
Significant Development ◽  
New Mother ◽  
Set Up ◽  
And Control

Pittenweem Priory began life as the caput manor of a daughter-house established on May Island by Cluniac monks from Reading (c. 1140). After its sale to St Andrews (c. 1280), the priory transferred ashore. While retaining its traditional name, the ‘Priory of May (alias Pittenweem)’ was subsumed within the Augustinian priory of St Andrews. Its prior was elected from among the canons of the new mother house, but it was many decades before a resident community of canons was set up in Pittenweem. The traditional view, based principally on the ‘non-conventual’ status of the priory reiterated in fifteenth-century documents, is that there was ‘no resident community’ before the priorship of Andrew Forman (1495–1515). Archaeological evidence in Pittenweem, however, indicates that James Kennedy had embarked on significant development of the priory fifty years earlier. This suggests that, when the term ‘non-conventual’ is used in documents emanating from Kennedy's successors (Graham and Scheves), we should interpret it more as an assertion of superiority and control than as a description of realities in the priory.

scholarly journals Characterization of Mechanical Heterogeneity in Dissimilar Metal Welded Joints

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4145
Author(s):  
He Xue ◽  
Zheng Wang ◽  
Shuai Wang ◽  
Jinxuan He ◽  
Hongliang Yang
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Welded Joints ◽  
Structural Integrity ◽  
Material Interfaces ◽  
Mechanical Heterogeneity ◽  
Finite Element Software ◽  
Dissimilar Metal ◽  
Stress Changes

Dissimilar metal welded joints (DMWJs) possess significant localized mechanical heterogeneity. Using finite element software ABAQUS with the User-defined Material (UMAT) subroutine, this study proposed a constitutive equation that may be used to express the heterogeneous mechanical properties of the heat-affected and fusion zones at the interfaces in DMWJs. By eliminating sudden stress changes at the material interfaces, the proposed approach provides a more realistic and accurate characterization of the mechanical heterogeneity in the local regions of DMWJs than existing methods. As such, the proposed approach enables the structural integrity of DMWJs to be analyzed in greater detail.

scholarly journals Infection Prevention Considerations for a Multi-Mission Convention Center Field Hospital in Baltimore, Maryland during the COVID-19 Pandemic

2021 ◽  
pp. 1-21
Author(s):  
Jennifer A. Jones ◽  
Zishan K. Siddiqui ◽  
Charles Callahan ◽  
Surbhi Leekha ◽  
Sharon Smyth ◽  
...  
Keyword(s):  
Best Practices ◽  
Infection Prevention ◽  
Diagnostic Testing ◽  
The United States ◽  
Infection Prevention And Control ◽  
Field Hospital ◽  
First Case ◽  
Convention Center ◽  
Set Up ◽  
And Control

Abstract The state of Maryland identified its first case of COVID-19 on March 5, 2020. The Baltimore Convention Center (BCCFH) quickly became a selected location to set up a 250-bed inpatient Field Hospital and Alternate Care Site. In contrast to other field hospitals throughout the United States, the BCCFH remained open throughout the pandemic and took on additional COVID-19 missions, including community SARS-CoV-2 diagnostic testing, monoclonal antibody infusions for COVID-19 outpatients, and community COVID-19 vaccinations. At the time of publication, the BCCFH had cared for 1,478 COVID-19 inpatients, performed 108,155 COVID-19 tests, infused 2,166 COVID-19 patients, and administered 115,169 doses of COVID-19 vaccine. To prevent the spread of pathogens during operations, infection prevention and control guidelines were essential to ensure the safety of staff and patients. Through multi-agency collaboration, utilization of infection prevention best practices, and answering what we describe as “PPE-ESP”, an operational framework was established to reduce infection risks for those providing or receiving care at the BCCFH during the COVID-19 pandemic.

scholarly journals Real time surveillance of COVID-19 space and time clusters during the summer 2020 in Spain

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nicolás Rosillo ◽  
Javier Del-Águila-Mejía ◽  
Ayelén Rojas-Benedicto ◽  
María Guerrero-Vadillo ◽  
Marina Peñuelas ◽  
...  
Keyword(s):  
Real Time ◽  
Scan Statistic ◽  
Cluster Aggregation ◽  
Space And Time ◽  
Spatial Trends ◽  
Community Transmission ◽  
Low Incidence ◽  
Set Up ◽  
And Control ◽  
Time Scan

Abstract Background On June 21st de-escalation measures and state-of-alarm ended in Spain after the COVID-19 first wave. New surveillance and control strategy was set up to detect emerging outbreaks. Aim To detect and describe the evolution of COVID-19 clusters and cases during the 2020 summer in Spain. Methods A near-real time surveillance system to detect active clusters of COVID-19 was developed based on Kulldorf’s prospective space-time scan statistic (STSS) to detect daily emerging active clusters. Results Analyses were performed daily during the summer 2020 (June 21st – August 31st) in Spain, showing an increase of active clusters and municipalities affected. Spread happened in the study period from a few, low-cases, regional-located clusters in June to a nationwide distribution of bigger clusters encompassing a higher average number of municipalities and total cases by end-August. Conclusion STSS-based surveillance of COVID-19 can be of utility in a low-incidence scenario to help tackle emerging outbreaks that could potentially drive a widespread transmission. If that happens, spatial trends and disease distribution can be followed with this method. Finally, cluster aggregation in space and time, as observed in our results, could suggest the occurrence of community transmission.

scholarly journals Development of an Exercise Training Protocol to Investigate Arteriogenesis in a Murine Model of Peripheral Artery Disease

2019 ◽  
Vol 20 (16) ◽  
pp. 3956 ◽  
Author(s):  
Ayko Bresler ◽  
Johanna Vogel ◽  
Daniel Niederer ◽  
Daphne Gray ◽  
Thomas Schmitz-Rixen ◽  
...  
Keyword(s):  
Peripheral Artery Disease ◽  
Suitable Model ◽  
Peripheral Artery ◽  
Running Wheel ◽  
Limb Perfusion ◽  
Collateral Growth ◽  
Artery Disease ◽  
Set Up ◽  
Exercise Induced ◽  
And Control

Exercise is a treatment option in peripheral artery disease (PAD) patients to improve their clinical trajectory, at least in part induced by collateral growth. The ligation of the femoral artery (FAL) in mice is an established model to induce arteriogenesis. We intended to develop an animal model to stimulate collateral growth in mice through exercise. The training intensity assessment consisted of comparing two different training regimens in C57BL/6 mice, a treadmill implementing forced exercise and a free-to-access voluntary running wheel. The mice in the latter group covered a much greater distance than the former pre- and postoperatively. C57BL/6 mice and hypercholesterolemic ApoE-deficient (ApoE−/−) mice were subjected to FAL and had either access to a running wheel or were kept in motion-restricting cages (control) and hind limb perfusion was measured pre- and postoperatively at various times. Perfusion recovery in C57BL/6 mice was similar between the groups. In contrast, ApoE−/− mice showed significant differences between training and control 7 d postoperatively with a significant increase in pericollateral macrophages while the collateral diameter did not differ between training and control groups 21 d after surgery. ApoE−/− mice with running wheel training is a suitable model to simulate exercise induced collateral growth in PAD. This experimental set-up may provide a model for investigating molecular training effects.

scholarly journals How to take advantage of tablet computers: Effects of news structure on recall and comprehension

2015 ◽  
Vol 40 (4) ◽  
Author(s):  
Anna Van Cauwenberge ◽  
Leen d’Haenens ◽  
Hans Beentjes
Keyword(s):  
Eye Tracking ◽  
Tablet Computers ◽  
Tracking Method ◽  
News Stories ◽  
News Consumption ◽  
Set Up ◽  
And Control ◽  
Factual Recall

AbstractIn light of the growing use of tablets for news reading and mobile news consumption behaviors, this study examined whether an innovative way of structuring news on the tablet that mimics mobile news behaviors reinforced attention for, and learning from, news. Specifically, it was theorized that the chronological and associative structuring of news articles into so-called developing news stories would lead to more attention for news, and better recall and comprehension of news, than the linear print newspaper structure that newspaper publishers continue to copy from print to tablet. A multiple-day experiment was set up using the eye-tracking method to measure and control for attention. The results show that the developing news structure increased comprehension of news substantively, independently of attention effects; no effects were found on attention and factual recall.

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