Early career researchers and their publishing and authorship practices          下载免费PDF全文

David Nicholas  Blanca Rodríguez‐Bravo  Anthony Watkinson  Cherifa Boukacem‐Zeghmouri  Eti Herman  Jie Xu  Abdullah Abrizah  Marzena Świgoń 《Learned Publishing》2017,30(3):205-217

This study presents findings from the first year of the Harbingers research project, a 3‐year longitudinal study of early career researchers (ECRs), which sought to ascertain current and changing habits in scholarly communication. The study recruited 116 science and social science ECRs from seven countries who were subject to in‐depth interviews, and this paper reports on findings regarding publishing and authorship practices and attitudes. A major objective was to determine whether ECRs are taking the myriad opportunities proffered by new digital innovations, developing within the context of open science, open access, and social media, to publish their research. The main finding is that these opportunities are generally not taken because ECRs are constrained by convention and the precarious employment environment they inhabit and know what is best for them, which is to publish (in high impact factor journals) or perish.  相似文献   

Endophytes from medicinal plants and their potential for producing indole acetic acid,improving seed germination and mitigating oxidative stress     

Abdul Latif Khan  Syed Abdullah Gilani  Muhammad Waqas  Khadija Al-Hosni  Salima Al-Khiziri  Yoon-Ha Kim  Liaqat Ali  Sang-Mo Kang  Sajjad Asaf  Raheem Shahzad  Javid Hussain  In-Jung Lee  Ahmed Al-Harrasi 《Journal of Zhejiang University. Science. B》2017,18(2):125-137

Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) μmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.  相似文献   

Model reference control of LPV systems     

Ali Abdullah  Mohamed Zribi 《Journal of The Franklin Institute》2009,346(9):777-871

This paper deals with the problem of model reference control for linear parameter varying (LPV) systems. The LPV systems under consideration depend on a set of parameters that are bounded and available online. The main contribution of this paper is to design an LPV model reference control scheme for LPV systems whose state-space matrices depend affinely on a set of time-varying parameters that are bounded and available online. The design problem is divided into two subproblems: the design of the coefficient matrices of the controller and the design of the gain of the state feedback controller for LPV systems. The singular value decomposition is used to obtain the coefficient matrices, while the linear matrix inequality methodology is used to obtain the parameter-dependent state feedback gain of the control scheme. A simple numerical example is used to illustrate the proposed design and a coupled-tank process example is used to demonstrate the usefulness and practicality of the proposed design. Simulation and experimental results indicate that the proposed scheme works well.  相似文献   

Piper sarmentosum as an antioxidant on oxidative stress in human umbilical vein endothelial cells induced by hydrogen peroxide     

Abdul Hamid HAFIZAH  Zakaria ZAITON  Amom ZULKHAIRI  Adenan MOHD ILHAM  Megat Mohd Nordin NOR ANITA  Abdullah Mahdy ZALEHA 《Journal of Zhejiang University. Science. B》2010,11(5):357-365

Endothelial cell death due to increased reactive oxygen species(ROS) may contribute to the initial endothelial injury,which promotes atherosclerotic lesion formation.Piper sarmentosum(PS),a natural product,has been shown to have an antioxidant property,which is hypothesized to inhibit production of ROS and prevent cell injury.Thus,the present study was designed to determine the effects of PS on the hydrogen peroxide(H2O2)-induced oxidative cell damage in cultured human umbilical vein endothelial cells(HUVECs).In this experiment,HUVECs were obtained by collagenase perfusion of the large vein in the umbilical cord and cultured in medium M200 supplemented with low serum growth supplementation(LSGS).HUVECs were treated with various concentrations of H2O2(0-1000 μmol/L) and it was observed that 180 μmol/L H2O2 reduced cell viability by 50% as denoted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Using the above concentration as the positive control,the H2O2-induced HUVECs were concomitantly treated with various concentrations(100,150,250 and 300 μg/ml) of three different extracts(aqueous,methanol and hexane) of PS.Malondialdehyde(MDA),superoxide dismutase(SOD),catalase(CAT) and glutathione peroxidase(GPX) levels showed a significant increase(P0.05) in HUVECs compared to the negative control.However,PS extracts showed a protective effect on HUVECs from H2O2-induced cell apoptosis with a significant reduction in MDA,SOD,CAT and GPX levels(P0.05).Furthermore,PS had exhibited ferric reducing antioxidant power with its high phenolic content.Hence,it was concluded that PS plays a beneficial role in reducing oxidative stress in H2O2-induced HUVECs.  相似文献   

The impact of electronic communication technology on written language     

Mohd. Sahandri Gani B. Hamzah Mohd. Reza Ghorbani Saifuddin Kumar B. Abdullah 《美中教育评论》2009,6(11):75-79

Communication technology is changing things. Language is no exception. Some language researchers argue that language is deteriorating due to increased use in electronic communication. The present paper investigated 100 randomly selected electronic mails （e-mails） and 50 short messaging system （SMS） messages of a representative sample of international students in University Putra Malaysia （UPM） to find out the impact of these two specific modes of electronic communication on written language use. The e-mails from UPM International Students Association （UPM-ISA） yahoo group were content analyzed. A non-probability convenience sampling was used to select the 50 short message services sent to the researcher about different subject matters by Malaysian and international students at UPM. Then, they were also content analyzed. The results indicated that the language used in students＇ e-mails and SMS messaging was full of spoken-like spelling, unconventional use of punctuation and abbreviations, and ungrammatical sentences. However, the more in-depth content analysis of the data revealed that the written language is being creatively adapted, developed, and enhanced to suit the conditions of the electronic communication age. Syntactical and lexical reductions are just strategies used to reduce effort, time and space.  相似文献   

Implications of distance education on children with disabilities     

Mustafa Karnas  Beyza Alpaydın  Abdullah Eker 《Support for Learning》2023,38(2):98-118

Once the COVID-19 was announced as a pandemic by the World Health Organization at the beginning of 2020, almost all countries around the world shifted from traditional face to face education to distance education to prevent the spread of the virus. Türkiye implemented distance education practices through a web-based platform named education information network (EBA) and EBA TV channels. However, the rapid shift from traditional face to face education to distance education was challenging especially for students with disabilities, their parents and teachers because these students needed individualised education and some services which were impossible to implement remotely. The purpose of this study was to explore (a) the challenges that teachers and students faced during distance education; (b) the implications of distance education on students with disabilities. Further, this study explored opinions of special education teachers regarding how to make distance education more effective for students with disabilities. A semi-structured interview was conducted with 12 special education teachers. Findings demonstrated that distance education through EBA was neither sufficient nor convenient for most students with disabilities. Limitations of this study and suggestions for future research were discussed.  相似文献   

The impact of the pandemic on early career researchers' work-life and scholarly communications: A quantitative aerial analysis     

David Nicholas  Eti Herman  David Clark  Cherifa Boukacem-Zeghmouri  Blanca Rodríguez-Bravo  Abdullah Abrizah  Anthony Watkinson  David Sims  Marzena 'Świgoń  Jie Xu  Galina Serbina  Hamid R. Jamali  Carol Tenopir  Suzie Allard 《Learned Publishing》2023,36(2):128-140

After two-years of repeat interviewing early career sciences/social sciences researchers from around the world about their work life and scholarly communications in pandemic-times, the Harbingers-2 project is in a position to release quantitative data on the pandemic's overall impact. The data comes from around 50 questions asked in the third and final round of interviews with 147 early career researchers (ECRs), which had a codifiable element to them (such as yes, no, do not know). The 19 scholarly topics covered include: pandemic-related research; research funding; changes to the workplace/working from home; pandemic-incurred stress and anxiety; teaching; employment security; career progression; mentoring; assessment (including metrics); collaboration; searching/finding information; ethics; networking; informal communication; publishing; sharing; pre-prints; outreach; and scholarly transformations. The main findings are that in six broad aspects of ECRs' work-life and scholarly behaviour, more than 50% of ECRs were impacted by the pandemic, with remote teaching having the greatest impact. By way of comparison, in another six aspects there was little change, least of all when it came to sharing activities. Among the countries studied, Malaysia stood out as being the most impacted, and of the disciplines it was the medical sciences and the soft social sciences most impacted.  相似文献   

The ability of children to generalize selected science concepts     

Kemal Bin Abdullah  Walter E. Lowell 《科学教学研究杂志》1981,18(6):547-555

The study investigated the ability of primary and elementary school subjects to generalize two science concepts, Insect and Animal with and without instruction in the form of a mental set. It also examined the effects of age, IQ, and sex on the ability of the children to generalize these concepts. Two instruments measuring the ability to generalize the concepts Insect and Animal were developed. The results indicate that of the independent variables investigated, age and mental set significantly affected the ability to generalize the concepts Insect and Animal. It was found that the younger children's concepts were least developed and with age these concepts became more developed and more conceptual in nature. The ability to use information given in a mental set was found to be a function of age. The children in this study were more able to generalize the concept Insect than the concept Animal. The results suggest that children with age and instruction axe better able to master less general concepts than more geaeral ones. In addition, the study demonstrated that children are able to improve their learning of general concepts provided a great number and variety of instances and noninstances of the concept are used in the instruction. It was also found that the younger children were more perceptually bound than the older children. The younger children were unable to overcome the pull of perceptual attractiveness that the noninstances held for them despite instruction. The results suggest that teachers of such children should be aware of the conceptual level of the content being taught to such children to ensure appropriate and meaningful learning takes place.  相似文献   

Sci‐Hub: The new and ultimate disruptor? View from the front     

David Nicholas  Chrifa Boukacem‐Zeghmouri  Jie Xu  Eti Herman  David Clark  Abdullah Abrizah  Blanca Rodríguez‐Bravo  Marzena wigo&#x; 《Learned Publishing》2019,32(2):147-153

The Harbinger project was a 3‐year‐long international study of the changing attitudes and behaviours of early career researchers (ECRs). One of the aims of the project was to discover if ECRs were adopting disrupting platforms that, legitimately or illegitimately, promote openness and sharing. It has been alleged that such an adoption appeals to them as Millennials. More than 100 ECRs from seven countries were questioned annually, and questions about Sc‐Hub were raised as part of discussions about discovery and access. Interview data were supplemented by desk research and Google Trends statistics. It was found that Sci‐Hub use was increasing and that a quarter of the ECRs now use it, with French ECRs being the biggest users. However, Sci‐Hub is making little headway with ECRs from the UK, USA, Malaysia, and China, although in China's case, this can be explained by it being banned and the country having its own equivalent, www.91lib.com . Sci‐Hub is used as much for convenience as necessity; use is not connected to the strength of library provision and and it has been suggested that it represents a bigger threat to publishers than ResearchGate, whose star might be waning.  相似文献   

Kinetics of acoustic release of doxorubicin from stabilized and unstabilized micelles and the effect of temperature     

Ghaleb A. Husseini  Mario A. Diaz de la Rosa  Saif Al Mamary  Abdullah Al Baik 《Journal of The Franklin Institute》2011,348(1):125-133

Ultrasound is being investigated as a trigger mechanism to deliver high concentrations of chemotherapy drugs to cancerous tissues using polymeric micelles. In this paper, we examined the kinetics of acoustic release of doxorubicin using stabilized and non-stabilized micelles. Kinetic models were used to regress release and re-encapsulation time constants for three different compounds, namely non-stabilized Pluronic^® P105 micelles, P105 micelles stabilized using an interpenetrating network of N,N-diethylacrylamide and micelles formed by PEO-b-poly(NIPAAm-co-HEMA-lactate_n). Results showed that the kinetic release constant (k_r) depends on the micellar system under investigation. On the other hand, there is no statistically significant difference between re-encapsulation rate constants for stabilized and unstabilized micelles. We hypothesize that k_r depends on the degree of cross-linking or stabilization.  相似文献