bluuebunny/crossref_metadata_2025_split huggingface dataset:
Specific cardiolipin-SecY interactions are required for proton-motive-force stimulation of protein secretion
Authors: Corey Robin A. , Pyle Euan , Allen William J. , Casiraghi Marina , Miroux Bruno , Arechaga Ignacio , Politis Argyris , Collinson Ian 
Published: October 2017

AbstractThe transport of proteins across or into membranes is a vital biological process, achieved in every cell by the conserved Sec machinery. In bacteria, SecYEG combines with the SecA motor protein for secretion of pre-proteins across the plasma membrane, powered by ATP hydrolysis and the trans-membrane proton-motive-force (PMF). The activities of SecYEG and SecA are modulated by membrane lipids, particularly by cardiolipin, a specialised phospholipid known to associate with a range of energy-transducing machines. Here, we identify two specific cardiolipin binding sites on theThermotoga maritimaSecA-SecYEG complex, through application of coarse-grained molecular dynamics simulations. We validate the computational data and demonstrate the conserved nature of the binding sites usingin vitromutagenesis, native mass spectrometry and biochemical analysis ofEscherichia coliSecYEG. The results show that the two sites account for the preponderance of functional cardiolipin binding to SecYEG, and mediate its roles in ATPase and protein transport activity. In addition, we demonstrate an important role for cardiolipin in the conferral of PMF-stimulation of protein transport. The apparent transient nature of the CL interaction might facilitate proton exchange with the Sec machinery and thereby stimulate protein transport, by an as yet unknown mechanism. This study demonstrates the power of coupling the high predictive ability of coarse-grained simulation with experimental analyses, towards investigation of both the nature and functional implications of protein-lipid interactions.Significance StatementMany proteins are located in lipid membranes surrounding cells and cellular organelles. The membrane can impart important structural and functional effects on the protein, making understanding of this interaction critical. Here, we apply computational simulation to the identification of conserved lipid binding sites on an important highly conserved bacterial membrane protein, the Sec translocase (SecA-SecYEG), which uses ATP and the proton motive force (PMF) to secrete proteins across the bacterial plasma membrane. We experimentally validate and reveal the conserved nature of these binding sites, and use functional analyses to investigate the biological significance of this interaction. We demonstrate that these interactions are specific, transient, and critical for both ATP- and PMF- driven protein secretion.
Ki-67 and condensins support the integrity of mitotic chromosomes through distinct mechanisms
Authors: Takagi Masatoshi , Ono Takao , Natsume Toyoaki , Sakamoto Chiyomi , Nakao Mitsuyoshi , Saitoh Noriko , Kanemaki Masato T. , Hirano Tatsuya , Imamoto Naoko 
Published: October 2017

AbstractAlthough condensins play essential roles in mitotic chromosome assembly, Ki-67, a protein localizing to the periphery of mitotic chromosomes, had also been shown to make a contribution to the process. To examine their respective roles, we generated a set of HCT116-based cell lines expressing Ki-67 and/or condensin subunits that were fused with an auxin-inducible degron for their conditional degradation. Both the localization and the dynamic behavior of Ki-67 on mitotic chromosomes were not largely affected upon depletion of condensin subunits, and vice versa. When both Ki-67 and SMC2 (a core subunit of condensins) were depleted, ball-like chromosome clusters with no sign of discernible thread-like structures were observed. This severe defective phenotype was distinct from that observed in cells depleted of either Ki-67 or SMC2 alone. Our results show that Ki-67 and condensins, which localize to the external surface and the central axis of mitotic chromosomes, respectively, have independent yet cooperative functions in supporting the structural integrity of mitotic chromosomes.List of Abbreviations usedAIDauxin-inducible degronDOXdoxycyclineFRAPfluorescence recovery after photobleachingIAAindol-3-acetic acidmAClmAID-mClovermAChmAID-mCherryNEBDnuclear envelope breakdownSMCstructural maintenance of chromosomesSTLCS-Trityl-L-cysteinetopo IIαtopoisomerase IIα
Application of grey systems in predicting the degree of cotton spider mite infestations
Authors: Wang Shouhui , Dai Jianguo , Zhao Qingzhan , Cui Meina 
Published: October 2017

Purpose
Many factors affect the emergence and development of crop diseases and insect pests. Traditional methods for investigating this subject are often difficult to employ and produce limited data with considerable uncertainty. The purpose of this paper is to predict the annual degree of cotton spider mite infestations by employing grey theory.

Design/methodology/approach
The authors established a GM(1,1) model to forecast mite infestation degree based on the analysis of historical data. To improve the prediction accuracy, the authors modified the grey model using Markov chain and BP neural network analyses. The prediction accuracy of the GM(1,1), Grey-Markov chain, and Grey-BP neural network models was 84.31, 94.76, and 96.84 per cent, respectively.

Findings
Compared with the single grey forecast model, both the Grey-Markov chain model and the Grey-BP neural network model had higher forecast accuracy, and the accuracy of the latter was highest. The improved grey model can be used to predict the degree of cotton spider mite infestations with high accuracy and overcomes the shortcomings of traditional forecasting methods.

Practical implications
The two new models were used to estimate mite infestation degree in 2015 and 2016. The Grey-Markov chain model yielded respective values of 1.27 and 1.15, whereas the Grey-BP neural network model yielded values 1.4 and 1.68; the actual values were 1.5 and 1.8.

Originality/value
The improved grey model can be used for medium- and long-term predictions of the occurrence of cotton spider mites and overcomes problems caused by data singularity and fluctuation. This research method can provide a reference for the prediction of similar diseases.
Research on an exponential distribution reliability function model based on multi-source heterogeneous data supplements
Authors: Shao Heng , Fang Zhigeng , Zhang Qin , Hu Qian , Cai Jiajia , Tao Liangyan 
Published: October 2017

Purpose
As productions show characteristics of multi-varieties and small batch in a recent new product system, it is more difficult to acquire its failure rate data. With the help of expert experience information, the authors can get the interval estimation of failure rate data under different methods, so how to make the interval convergence with the new information is an important problem to be solved. The paper aims to discuss this issue.

Design/methodology/approach
In this paper, the concept of generalized standard grey number is used to characterize the multi-source heterogeneous uncertainty failure rate data into a unified framework. Then, the engineering construction method is used to calculate the average failure rate and build the grey exponential distribution reliability function, whose image is presented as the possible region of the two-curve envelope.

Findings
Further, according to the normal distribution assumption of the regional convergence based on the information supplement, the convergence problem of the reliability function is transformed into the convergence of the area of the curve envelope region, and construct the multi-objective programming model with the minimum envelope area and the lowest total cost of information acquisition, acquire the conclusion that the failure rate is equal to the nuclear of the average failure rate when the envelope region converges.

Originality/value
Through the case analysis of the equipment ejection system of the Harbinger system, five groups of results are obtained by Matlab simulation, which verify the rationality and feasibility of the model described in this paper.
Beginning teachers’ perceptions of mentors and access to communities of practice
Authors: Shields Samantha , Murray Megan 
Published: October 2017

Purpose
The purpose of this paper is to explore beginning teachers’ perceptions of the role of the mentor in the early stages of developing a professional identity. The beginning teachers in the authors’ study are defined as having been awarded qualified teacher status at the end of an initial teacher education programme or having completed their first term as a new teacher with responsibility for a class of pupils.

Design/methodology/approach
The research design was a qualitative, inductive study. The concepts of communities of practice, legitimate peripheral participation and power dynamics within a community underpinned this study. The data set was collected over a period of 18 months, through six focus groups and 40 questionnaires with beginning teachers across 34 schools altogether. The data set was analysed using interpretive phenomenological analysis (IPA).

Findings
The findings indicated that the ways in which mentors use their power to recognise (or not) the legitimacy of beginning teachers as being part of the school community influences the development of beginning teachers’ professional identities. The thematic analysis of the data indicated the different types of support that mentors may provide: “belonging”, “emotional”, “pedagogical” and “space”.

Research limitations/implications
Further research into how mentors perceive their role in supporting new entrants into the profession is needed.

Originality/value
These findings are pertinent in England, as the increase in school-based initial teacher training provision will intensify the role of school mentors. These findings will be of value to other countries that are moving towards an increase in school-based teacher training.
The effect of round corner on lubrication of high speed cylindrical roller bearings considering skidding
Authors: Cao Wei , Wang Jiaxu , Pu Wei , Zhang Ying , Wu Jiqiang , Ren Si , Long Jianbing 
Published: October 2017

Purpose
Previous studies were mainly focused on profile designation of bearing rollers and lubrication performance without considering roller-races skidding. However, the width of round corner, load, rotational speed and some other parameters have significant effects on the roller-races sliding speed. This paper aims to investigate the effect of round corner on lubricating characteristics between the heavily loaded roller and inner race considering skidding and roughness.

Design/methodology/approach
A mixed elastohydrodynamic lubrication (EHL) model which is capable of handling practical cases with 3D machined roughness is combined with the skidding model to investigate the effect of round corner on lubricating characteristics between the heavily loaded roller and inner race.

Findings
The width of round corner and round corner radius have a desirable range under certain operating condition, within which the maximum pressure, stress and maximum flash temperature remain low. The optimized range is sensitive to the operating condition. Roughness and skidding narrow the optimized range of round corner radius. Roughness increases the pressure peak, Mises stress and friction coefficient. At the same time, skidding and roughness have obvious effects on film thickness at the contact center area if the round radius is small.

Research limitations/implications
This paper uses the Harris skidding model that has a relatively bigger error, which is not accurate if the bearing load is less.

Practical implications
This paper unifies the skidding model and mixed EHL model which can be used as a tool for optimization design and lubricating performance analysis of cylindrical roller bearing.

Originality/value
Lubrication analyses for roller bearing are assumed to be pure rolling contact between roller and races in a previous study, which could not reflect the real contact characteristics. The skidding model is merged into a mixed EHL model which can be used as a dynamic tool to analyze the lubricating performance considering the round corner, skidding and roughness.
Investigation of slip/no-slip surface for two-dimensional large tilting pad thrust bearing
Authors: Song Zhixiang , Guo Fei , Liu Ying , Hu Songtao , Liu Xiangfeng , Wang Yuming 
Published: October 2017

Purpose
This paper aims to present the slip/no-slip design in two-dimensional water-lubricated tilting pad thrust bearings (TPTBs) considering the turbulence effect and shifting of pressure centers.

Design/methodology/approach
A numerical model is established to analyze the slip condition and the effect of turbulence according to a Reynolds number defined in terms of the slip condition. Simulations are carried out for eccentrically and centrally pivoted bearings and the influence of different slip parameters is discussed.

Findings
A considerable enhancement in load capacity, as well as a reduction in friction, can be achieved by heterogeneous slip/no-slip surface designs for lubricated sliding contacts, especially for near parallel pad configurations. The optimized design largely depends on the pivot position. The load capacity increases by 174 per cent for eccentrically pivoted bearings and 159 per cent for centrally pivoted bearings for a suitable design. When slip zone locates at the middle of the radial direction or close to the inner edge, the performance of the TPTB is better.

Research limitations/implications
The simplification of slip effect on the turbulence (definition of Reynolds number) can only describe the trend of the increasing turbulence due to slip condition. The accurate turbulence expression considering the boundary slip needs further explorations.

Originality/value
The shifting of pressure center due to the slip/no-slip design for TPTBs is investigated in this study. The turbulence effect and influence of slip parameters is discussed for large water-lubricated bearings.
Analysis of coning and lubrication at flexspline cup and cam interface in conventional harmonic drives
Authors: Routh Bikash , Maiti Rathindranath , Ray Asok Kumar 
Published: October 2017

Purpose
In a harmonic drive during assembly of its components like strain wave generating (SWG) cam, flexspline (FS) and circular spline, a gap is formed between the cam’s outer surface and the FS cup inner surface due to mismatching. This gap, which is known as “Coning”, plays a vital role in the flow of lubricant at that interface. This paper aims to analyse the coning phenomenon and the lubrication mechanism.

Design/methodology/approach
In the present investigation, the geometry of the coning gap and its variation with the SWG cam rotation are established. Essentially, the deflection of FS cup and deformation of SWG cam (bearing outer race) are derived to find the gap due to coning. Next, the hydrodynamic lubrication equation is solved to get pressure profiles for this gap under suitable boundary conditions assuming non-Newtonian lubrication.

Findings
Methods of estimating the coning gap and lubrication pressure profiles are established. Effects of non-Newtonian terms (coupling number and non-dimentionalized characteristic length) and SWG length (finite, long and short) on pressure profiles are also shown. All analyses are done in non-dimensionalized form.

Originality/value
Establishing the geometry of coning and non-Newtonian hydrodynamic lubrication aspects in the coning in the FS cup and SWG cam interface are the originality of the present investigation.
Micro-scratch behaviour of adsorbed film formed by aqueous copolymer lubricants with phosphate ester additive on Ti-coated surface
Authors: Lin Bingjing , Tieu A. Kiet , Zhu Hongtao , Kosasih Buyung , Novareza Oyong 
Published: October 2017

Purpose
This paper aims to assess the adsorption behaviour and the adhesion strength of lubricant films formed by polypropylene oxide-polyethylene oxide-polypropylene oxide (PPO-PEO-PPO) with phosphate ester additive on Ti-coated surface and to identify the influence of molecular architecture and phosphate ester additive.

Design/methodology/approach
The thickness of the adsorbed PPO-PEO-PPO with phosphate ester lubricant films on Ti surfaces was measured by ellipsometry. The adhesion strength of the copolymer and the copolymer with phosphate ester lubricants was studied by the micro-scratch tests; the scratch tracks on the surfaces were observed by atomic force microscopy and scanning electronic microscopy.

Findings
The copolymer with a higher weight percentage of PPO not only formed a thicker film but also showed stronger adhesion and better lubrication performance. The added phosphate ester increased the film thickness and improved the tribological behaviour. The finding reveals that the adsorbed film thickness which depends on the PPO chain length and the presence of phosphate ester has a considerable effect on the scratch behaviour.

Originality/value
This paper fulfils the studies about adsorption behaviour and lubrication mechanism of this new lubricant which has not been adequately investigated on the metal surface.
Integral transform solution for the analysis of hydrodynamic lubrication of thrust bearings
Authors: Medeiros Nielson Veloso , Macêdo Emanuel Negrão , Magno Rui Nelson Otoni , Blanco Claudio José Cavalcante , Quaresma João Nazareno Nonato 
Published: October 2017

Purpose
The aim of this paper is related to an analysis of hydrodynamic lubrication of circular thrust bearings.

Design/methodology/approach
The modified Reynolds equation was treated to obtain a hybrid numerical-analytical solution through the generalized integral transform technique (GITT) for the problem.

Findings
Numerical results for the engineering parameters such as pressure field, load capacity and power consumption were thus produced as functions of the radial and circumferential directions. These parameters depend on the geometry of sector-shaped used: Rayleigh pad with 4, 8 and 16 steps. Comparing among them, on the numerical point of view, the Rayleigh pad geometry with N = 16 steps has a better satisfactory performance because it has a lower power consumption.

Originality/value
The present GITT results and those obtained by the finite volume method (FVM) from previous works in the literature were confronted to verify whether the results are consistent and to demonstrate the capacity of the GITT approach in handling thrust bearing problems.
Collaborative innovation capability in IT-enabled inter-firm collaboration
Authors: Wang Fei , Zhao Jing , Chi Maomao , Li Yajing 
Published: October 2017

Purpose
With the increasingly collaborative nature of innovation and the expanding role of digital platforms on inter-firm collaboration, the purpose of this paper is to investigate the impacts of digital platforms on collaborative innovation capability (CIC) under conditions of two distinctive governance mechanisms. Furthermore, the competitive benefits of CIC at different levels of environmental uncertainty are examined to clarify the performance of collaborative innovation.

Design/methodology/approach
The research model is proposed based on dynamic capabilities theory, information technology (IT)-enabled organizational capability and governance mechanisms literature, and then validated by using partial least squares with data collected from 200 Chinese firms that engage in digital collaboration with their major channel distributors.

Findings
Empirical results show that the enabling effect of digital platforms capability on CIC is positively moderated by relational governance while negatively moderated by formal governance, and both governance mechanisms directly and positively influence CIC; the positive relationship between CIC and competitive performance is stronger for higher level of environmental uncertainty; and CIC is the key mediator converting digital platforms capability into competitive performance.

Originality/value
This study enriches the existing literatures in IT-innovation relationship by not only surfacing the interplay of digital platforms capability with two distinctive governance mechanisms in building CIC, but also clarifying the competitive benefits of CIC in an uncertain environment. Moreover, this study helps explain the controversial issue of the business value of IT capability by discovering the mediating role of CIC.
Sounding out d/Deafness: the experiences of d/Deaf prisoners
Authors: Kelly Laura Margaret 
Published: October 2017

Purpose
The purpose of this paper is to provide an insight into the lived realities of d/Deaf prisoners in England and Wales, and to explore previous claims that they suffer disproportionately during their time in custody.

Design/methodology/approach
For the purposes of this study, a qualitative approach was taken. As part of this, 28 semi-structured interviews were carried out at seven adult male prisons in England with a sample of male hard of hearing/d/Deaf prisoners, and staff members who had worked with them. The interviews were recorded using a Dictaphone, and then transcribed as close to verbatim as possible. From this, the transcriptions were analysed using thematic analysis. In addition to interviews, observations were made at each establishment, and later recorded in a fieldwork journal.

Findings
Findings from the study showed that the way a d/Deaf person experiences prison depends strongly on the way in which they identify with their d/Deafness. However, it was also shown that there is little room for either deafness or Deafness in prison, with severely deaf and culturally and linguistically Deaf prisoners commonly experiencing the pains of imprisonment more severely than their hearing peers as a result of the Prison Service’s inability to accommodate such difference.

Originality/value
This study fused together the fields of Deaf Studies and Prison Studies in a way that had not been done before, considering d/Deafness in prison on both an audiological and cultural level. Moreover, excluding small-scale unpublished undergraduate dissertations, it was the first empirical study about d/Deaf prisoners in England and Wales to carry out face-to-face interviews with these prisoners. Finally, as the most in-depth research is yet to be carried out about these particular prisoners in England and Wales, a greater level of insight was provided than previously available.
Host effects on microbiota community assembly
Authors: Näpflin Kathrin , Schmid‐Hempel Paul 
Published: October 2017

Abstract

To what extent host‐associated microbiota assembly is driven by host selection or simply by happenstance remains an open question in microbiome research.

Here, we take a first step towards elucidating the relative importance of host selection on the establishing gut microbial community in an ecologically relevant organism.

We presented germ‐free bumblebee, Bombus terrestris, workers from 10 colonies with a “global” microbial species pool comprised of an equal mixture of the gut microbiota of all colonies.

By means of 16S amplicon sequencing, we found that overall microbiota community composition was generally shifted between pool‐exposed workers compared to workers that naturally acquired their gut microbiota, but that the specific composition of the established microbiota also depended on colony identity (e.g. genetic background).

Because the microbiota is protective against parasite infection in this system, variation in the filtering of a beneficial microbial community can have important consequences for host resistance and eventual co‐evolution with parasites.