scholarly journals Alternative Molecular Methods for Improved Detection of Meningococcal Carriage and Measurement of Bacterial Density

2016 ◽  
Vol 54 (11) ◽  
pp. 2743-2748 ◽  
Author(s):  
Olivier Manigart ◽  
Jacinta Okeakpu ◽  
Aderonke Odutola ◽  
Sheikh Jarju ◽  
Ebenezer Foster-Nyarko ◽  
...  

Conventional methods for detecting pharyngeal carriage of Neisseria meningitidis are complex. There is a need for simpler methods with improved performance. We have investigated two alternative approaches. Three pharyngeal swabs were collected from 999 pupils aged 10 to 18 years in The Gambia. Carriage of N. meningitidis was investigated by using three different methods: (i) plating on Thayer-Martin selective medium and testing by conventional microbiological methods followed by PCR testing; (ii) seeding in Todd-Hewitt broth (THB) and, after culture overnight, testing by PCR; and (iii) compression of the swab on filter paper and, after DNA concentration, testing by PCR. PCR after culture in THB was more than twice as sensitive as conventional methods in detecting N. meningitidis (13.2% versus 5.7%; P < 0.0001). PCR after DNA extraction from filter paper had a sensitivity similar to that of conventional methods (4.9% versus 5.7%; P = 0.33). Capsular genogroups detected by broth culture were genogroups W (21 isolates), B (12 isolates), Y (8 isolates), E (3 isolates), and X (2 isolates), and 68 meningococci had the capsule-null intergenic region. The distributions of genogroups and of capsule-null organisms were similar with each of the three methods. The carriage density in samples extracted from filter paper ranged from 1 to 25,000 DNA copies. PCR of broth cultures grown overnight doubled the yield of N. meningitidis carriage isolates compared with conventional methods. This approach could improve the efficiency of carriage studies. Collection on filter paper followed by quantitative PCR could be useful for density measurement and for carriage studies in areas with limited resources.

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Mihnea R. Mangalea ◽  
Emily K. Luna ◽  
Janet Ziegle ◽  
Christine Chang ◽  
Angela M. Bosco-Lauth ◽  
...  

Pandoraea pnomenusa strain TF-18 was isolated from the roots of rice seedlings on selective medium containing four classes of antibiotics for isolation of Burkholderia pseudomallei. Using Pacific Biosciences (PacBio) single-molecule real-time (SMRT) sequencing technology, we report here a complete genome of 5,499,432 bases, a GC content of 64.8%, and 4,849 coding sequences.


2018 ◽  
Vol 24 (6) ◽  
pp. 935-944 ◽  
Author(s):  
Mingke Li ◽  
Wangyu Liu

PurposeThe purpose of this paper is to present the novel parameterized digital-mask generation method which is aimed at enhancing bio-scaffold’s fabricating efficiency with digital micro-mirror device (DMD)-based systems.Design/methodology/approachA method to directly generate the digital masks of bio-scaffolds without modeling the entire 3D scaffold models is presented. In most of the conventional methods, it is inefficient to dynamically modify the size of the structural unit cells during design, because it relies more or less on commercial computer aided design (CAD) platforms. The method proposed in this paper can achieve high efficient parameterized design, and it is independent from any CAD platforms. The generated masks in binary bitmap format can be used by the DMD-based to achieve scaffold’s additive manufacture. In conventional methods, the Boolean operation of the external surface and the internal architectures would result in the damage of unit cells in boundary region. These damaged unit cells not only lose its original mechanical property but also cause numbers of gaps and isolated features that would reduce the geometric accuracy of the fabricated scaffolds; the proposed method in this paper provides an approach to tackle this defect.FindingsThe results show that the proposed method can improve the digital masks generation efficiency.Practical implicationsThe proposed method can serve as an effective supplement to the slicing method in additive manufacture. It also provides a way to design and fabricate scaffolds with heterogeneous architectures.Originality/valueThis paper gives supports to fabricate bio-scaffold with DMD-based systems.


2016 ◽  
Vol 23 (7) ◽  
pp. 610-617 ◽  
Author(s):  
Anuradha Sinha ◽  
Ayan Dey ◽  
Giulietta Saletti ◽  
Pradip Samanta ◽  
Partha Sarathi Chakraborty ◽  
...  

Developing countries are burdened withShigelladiarrhea. Understanding mucosal immune responses associated with naturalShigellainfection is important to identify potential correlates of protection and, as such, to design effective vaccines. We performed a comparative analysis of circulating mucosal plasmablasts producing specific antibodies against highly conserved invasive plasmid antigens (IpaC, IpaD20, and IpaD120) and two recently identified surface protein antigens,pan-Shigellasurfaceprotein antigen 1 (PSSP1) and PSSP2, common to all virulentShigellastrains. We examined blood and stool specimens from 37 diarrheal patients admitted to the Infectious Diseases & Beliaghata General Hospital, Kolkata, India. The etiological agent of diarrhea was investigated in stool specimens by microbiological methods and real-time PCR. Gut-homing (α4β7+) antibody-secreting cells (ASCs) were isolated from patient blood by means of combined magnetic cell sorting and two-color enzyme-linked immunosorbent spot (ELISPOT) assay. Overall, 57% (21 of 37) and 65% (24 of 37) of the patients were positive forShigellainfection by microbiological and real-time PCR assays, respectively. The frequency of α4β7+IgG ASC responders against Ipas was higher than that observed against PSSP1 or PSSP2, regardless of theShigellaserotype isolated from these patients. Thus, α4β7+ASC responses to Ipas may be considered an indirect marker ofShigellainfection. The apparent weakness of ASC responses to PSSP1 is consistent with the lack of cross-protection induced by naturalShigellainfection. The finding that ASC responses to IpaD develop in patients with recent-onset shigellosis indicates that such responses may not be protective or may wane too rapidly and/or be of insufficient magnitude.


2018 ◽  
Vol 70 (1) ◽  
pp. 68-75 ◽  
Author(s):  
Jun-peng Shao ◽  
Guang-dong Liu ◽  
Xiao-dong Yu ◽  
Yan-qin Zhang ◽  
Xiu-li Meng ◽  
...  

Purpose The purpose of this paper is to describe a simulation and experimental research concerning the effect of recess depth on the lubrication performance of a hydrostatic thrust bearing by constant rate flow. Design/methodology/approach The computational fluid dynamics and finite volume method have been used to compute the lubrication characteristics of an annular recess hydrostatic thrust bearing with different recess depths. The performances are oil recess pressure, oil recess temperature and oil film velocity. The recess depth has been optimized. A test rig is established for testing the pressure field of the structure of hydrostatic thrust bearing after recess depth optimization, and experimental results show that experimental data are basically identical with the simulation results, which demonstrates the validity of the proposed numerical simulation method. Findings The results demonstrate that the oil film temperature decreases and the oil film pressure first increases and then decreases with an increase in the recess depth, but oil film velocity is constant. To sum up comprehensive lubrication performance, the recess depth of 3.5 mm is its optimal value for the annular recess hydrostatic thrust bearing. Originality/value The computed results indicate that to get an improved performance from a constant flow hydrostatic thrust bearing, a proper selection of the recess depth is essential.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jinqiang Wang ◽  
Yaobin Lu ◽  
Si Fan ◽  
Peng Hu ◽  
Bin Wang

PurposeThe purpose of the research is to explore how small and medium enterprises (SMEs) in central China achieve intelligent transformation through the use of artificial intelligence (AI). Because of unequal resource allocation, constraints on the intelligent transformation of SMEs in central China are different from those in economically and technologically well-developed coastal provinces. Hence, the authors focus on SMEs in central China to identify drivers of and barriers to intelligent transformation.Design/methodology/approachThe interview data were collected from 66 SMEs across 20 industries in central China. To verify the validity of the data collection method, the authors used two methods to control for retrospective bias: multi-level informants and enterprises' AI project application materials (Wei and Clegg, 2020). The final data were validated without conflicts. Next, the authors cautiously followed a two-step approach recommended by Venkatesh et al. (2010) and used NVivo 11.0 to analyze the collected text data.FindingsSMEs in central China are enthusiastic about intelligent transformation while facing both internal and external pressures. SMEs need to pay attention to both internal (enterprise development needs, implementation cost, human resources and top management involvement) and external factors (external market pressure, convenience of AI technology and policy support) and their different impacts on intelligent transformation. However, constrained by limited resources, SMEs in central China have been forced to take a step-by-step intelligent transformation strategy based on their actual needs with the technological flexibility method in the short term.Originality/valueConsidering the large number of SMEs and their importance in promoting China's economic development and job creation (SME Bureau of MIIT, 2020), more research on SMEs with limited resources is needed. In the study, the authors confirmed that enterprises should handle “social responsibility” carefully because over-emphasizing it will hinder intelligent transformation. However, firms should pay attention to the role of executives in promoting intelligent transformation and make full use of policy support to access more resources.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Stephen Gray ◽  
Jason Hall ◽  
Grant Pollard ◽  
Damien Cannavan

Purpose In the context of public-private partnerships (PPPs), it has been argued that the standard valuation framework produces a paradox whereby government appears to be made better off by taking on more systematic risk. This has led to a range of approaches being applied in practice, none of which are consistent with the standard valuation approach. The purpose of this paper is to demonstrate that these approaches are flawed and unnecessary. Design/methodology/approach The authors step through the proposed alternative valuation approaches and demonstrate their inconsistencies and illogical outcomes, using theory, logic and mathematical proof. Findings In this paper, the authors demonstrate that the proposed (alternative) approaches suffer from internal inconsistencies and produce illogical outcomes in some cases. The authors also show that there is no problem with the current accepted theory and that the apparent paradox is not the result of a deficiency in the current theory but is rather caused by its misapplication in practice. In particular, the authors show that the systematic risk of cash flows is frequently mis-estimated, and the correction of this error solves the apparent paradox. Practical implications Over the past 20 years, PPP activity around the globe amounts to many billions of dollars. Decisions on major infrastructure funding are of enormous social and economic importance. Originality/value To the best of the authors’ knowledge, this study is the first to demonstrate the flaws and internal inconsistencies with proposed valuation framework alternatives for the purposes of evaluating PPPs.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Marcel C. Minutolo ◽  
Albena Ivanova ◽  
Michelle Cong

Purpose The purpose of this paper is to develop an integrated model assessing the frequency and timing between reports on the Association for the Advancement of Sustainability in Higher Education (AASHE) Sustainability Tracking, Assessment and Rating System (STARS) reporting the framework by higher education institutions (HEIs) and the relationship between the STARS score and reputation (enrollment), finances (endowment) and performance (emissions). Design/methodology/approach The development of the theoretical model is based on learning, signaling and legitimacy theories. This study collects data from the AASHE STARS to indicate the rating level of 202 HEIs, control variables, enrollment, endowments and emissions. The hypotheses were tested using generalized linear models. Findings Findings suggest that as HEIs report on their sustainability activity, they learn to report better but that there is also an “un-learning” aspect if the HEI skips reporting in a period. The results support the main hypothesis that there is a relationship between reporting and engagement with the HEIs in the form of enrollment and endowments. Finally, the findings provide evidence that the HEIs’ reporting is associated with a reduction in emissions. Practical implications The findings suggest that HEIs should develop a reporting strategy on a standardized framework such as AASHE STARs and they ought to codify the approach to learn from prior reporting. Students and alumni are increasingly seeking to engage the HEI in the sustainability process and the report is a mechanism for signaling activities. Social implications The findings suggest that AASHE STARS scores may be used by HEIs as a signaling mechanism to stakeholders of their commitment to sustainability. The signal is a mechanism to reduce information asymmetry between the HEI and stakeholders who may want more information on the institution’s attempts toward sustainability but lack access to information. Further, HEI partners have a mechanism to assess the overall level of commitment of the HEI toward sustainability and can, therefore, engage accordingly. Originality/value There has been significant work on signaling theory and sustainability. However, the relationship between STARs reporting as a signal that legitimates the HEI, learning how to report well and HEI performance has received less attention. The current study demonstrates that the STARS framework as a reporting mechanism signals the HEIs’ level of commitment to sustainability thereby legitimating it resulting in improved performance.


RSC Advances ◽  
2017 ◽  
Vol 7 (62) ◽  
pp. 39172-39177 ◽  
Author(s):  
Jing Zhang ◽  
Heqin Li ◽  
Zhiwei Lin ◽  
Qiong Tang ◽  
Weiyu Qi ◽  
...  

A carbon film was prepared by filter paper and modified by radio-frequency magnetron sputtering as a conductive interlayer for lithium–sulfur batteries.


2017 ◽  
Vol 33 (2) ◽  
pp. 100-116 ◽  
Author(s):  
Sara Mannheimer ◽  
Conor Cote

Purpose For libraries with limited resources, digital preservation can seem like a daunting responsibility. Forming partnerships can help build collective knowledge and maximize combined resources to achieve digital preservation goals. This paper aims to provide guidance to help libraries with limited resources achieve digital preservation goals by forming partnerships to build collective knowledge and maximize combined resources. Design/methodology/approach In 2015, librarians from four Montana institutions formed the Digital Preservation Working Group (DPWG), a collaboration to increase digital preservation efforts statewide. The group’s immediate goals were to promote digital preservation best-practices at each individual institution, and to learn about and support each other’s work. The group’s long-term goal was to implement a shared digital preservation service that would fill gaps in existing digital preservation efforts. Findings Beyond the cost savings gained by sharing a digital preservation service, the members of DPWG benefitted from shared knowledge and expertise gained during the partnership. The group also functioned as a sounding board as each institution built its digital preservation program, and it became a system of support when challenges arose. Practical/implications This paper proposes a five-point plan for creating digital preservation partnerships: cultivate a foundation of knowledge and identify a shared vision; assess the current digital preservation landscape at each institution; advocate for the value of digital preservation activities; implement shared digital preservation services; and sustain group activities and establish structures for ongoing support. Originality/value The activities of DPWG provide a model for institutions seeking to collaborate to meet digital preservation challenges. This paper shows that by implementing a structured plan, institutions can build and sustain digital preservation partnerships, thus positioning themselves to achieve digital preservation success.


2018 ◽  
Vol 33 (8) ◽  
pp. 1087-1099
Author(s):  
Tale Skjølsvik

Purpose While goods- and service-dominant logics are separated in most research as alternative and often incompatible paradigms, this paper aims to show how these logics can be and are combined in purchasing strategies in organizations. The paper also illustrates that multiple logics exist in addition to purely goods- or service-based logics. Design/methodology/approach The paper is based on empirical data on the purchasing of management consulting services, which represent an extreme context for understanding the combination and intersection of goods- and service-dominant logics. In particular, four in-depth case studies and interviews with 51 sellers and 30 buyers of management consulting services are used to develop a typology of purchasing approaches that combines goods- and service-dominant logics. Findings The study shows that goods- and service-dominant logics are combined in two main purchasing phases: supplier set selection and assignment selection. In both these phases, parallel and knowledge-based, embedded and experience-based approaches were identified as ways of combining goods- and service-dominant logics in the purchasing context. Research limitations/implications The research presented in the following adds to our existing understanding of possible purchasing strategies under multiple logics in buying organizations. Future research should explore the conditions under which different strategies are and should be applied in organizations. Practical implications This paper gives practitioners alternative approaches to choose from in their purchasing and sales of knowledge-intensive services, in addition to transactional and relational strategies. Originality/value The research adds to existing research on business and industrial marketing by identifying particular purchasing strategies on a continuum between goods- and service-dominant logics.


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