bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of designed nursing guidelines on acute anal fissure treatment outcomes
Authors: Abd-Elmaged Esmat Sayed , Desoky Amna Abdallh , Abd-Elrahem Tarik Abd-Elazem
Published: May 2018

Objective: Anal fissure is a common problem through the world, it causes considerable morbidity. The aim of the study was to evaluate the effect of designed nursing guidelines on acute anal fissure treatment outcomes.Methods: Research design: Quasi-experimental design. Setting: General Surgery Wards and Outpatient Clinics of General Surgery at Assiut University Hospital. Sample: A purposive sample of 60 male and female adult patients diagnosed of having acute anal fissure. Patients were equally divided on random basis into two equal groups (study and control) 30 patients for each. Tools: Tool I-Patient assessment sheet. Tool II-Numeric Pain Rating Scale. Tool III-Bates-Jensen Wound Assessment Tool.Results: No statistically significant difference was found between the study and the control groups as regard demographic data. There was a statistically significant improvement in the pain level and wound healing among the study group (1.63 ± 2.08 and 11.93 ± 4.5 respectively) than in the control group (2.87 ± 2.33 and 14.43 ± 4.29 respectively). Also, there was a high statistically significant improvement in the level of knowledge of the study group than their level before applying the guidelines (p < .001).Conclusions: Designed nursing guidelines had a statistically significant effect on improving patients' knowledge, pain level, and wound healing among the study group patients than among the control group ones with acute anal fissure. Recommendations: Patients teaching should be an integral part of the nurses' duty in all hospitals. Further studies on larger sample from different geographical areas in Egypt to generalize the results.
Problem-based Learning: Nursing students’ attitude, self-reported competence, tutorial performance and self-directed learning readiness
Authors: Bruce Judith C. , Lack Melanie , Bomvana Nthabiseng M. , Qamata-Mtshali Nomawethu
Published: May 2018

Background and objectives: Problem-based learning (PBL) is widely recognized as progressive pedagogy for the preparation of a range of health professionals. Despite the prominence of PBL in contemporary discussions about the education of future health professionals, its value is increasingly being contested in light of shrinking resources and increasing student enrolments in universities.  The objectives were to ascertain Bachelor of Nursing (BN) students’ attitude towards the value of PBL as a learning strategy; to determine BN students’ degree of certainty about their competence in PBL processes; to determine whether student performance in PBL tutorials improve over four years of study; and to compare the self-directed learning readiness of PBL students to those who are not exposed to PBL.Methods: The study followed a descriptive and comparative survey design to collect the data. Participants were BN students who were invited to participate in the descriptive survey (n = 92), and purposively selected (n = 159) for comparison between PBL (n = 54) and non-PBL (n = 105) groups.Results: The majority of students found PBL a stimulating (59.8%; n = 55), useful (65.2%; n = 60), empowering (70.6%; n = 65) and enlightening (60.8%; n = 56) learning strategy; most students (53.2%; n = 49) expressed certainty about their competence in “accessing relevant literature/evidence” but more (56.3%; n = 52) were less certain about their ability to “integrate information into nursing care”. First year students performed poorly in PBL tutorials but showed a significant improvement in the final year of study in problem-solving (p = .0001), contribution to the group (p = .000), communication (p = .000), critical thinking (p = .001), learning skills (p = .001), personal growth (p = .000) and leadership skills (p = .041). There was no significant difference between PBL and non-PBL students’ overall readiness for self-directed learning (p = .69).Conclusions: The findings suggest that BN students generally have a positive attitude towards PBL, finding it stimulating, useful, empowering and enlightening in a transformative learning environment. However, fewer students feel that they are competent in the majority of the PBL processes. The biggest learning gains for students during PBL tutorials are in problem-solving, contributions to the group, communication, learning skills, critical thinking, personal growth and leadership. PBL and non-PBL students are similar in their self-directed learning readiness regardless of the learning strategy used.
Leader, Government, and Market: The Economic Development of South Korea and Taiwan in the 70s and 80s
Authors: Han Daehoon
Published: May 2018

South Korea and Taiwan experienced the extremely rare type of high-level, sustained postwar economic growth.While it has attracted the attention of many scholars who found out the identical pattern of economic developmentbetween South Korea and Taiwan by focusing on the similar structural conditions, relatively less attention has beengiven to the development mechanism South Korea and Taiwan employed to develop their economy. Furthermore,few studies have highlighted the role of actors in the process of economic development in South Korea and Taiwanbecause most of previous studies have focused on the structural conditions. This study aimed to examine how SouthKorea and Taiwan have developed their economy by discovering the type of a development mechanism employed.Based on using the set of secondary data source, this study found out that South Korea and Taiwan achieved aphenomenal economic development based on the export-oriented industrialization. However, South Korean economywas developed by the government-led development mechanism, while Taiwanese economy was developed by themarket-led development mechanism. And, the difference in the way of developing their economy was mainly causedby not only several structural conditions, such as the consensus between the government and private sector over thematter of economic development, the urgency of economic development, and the existence of vertical social system,but also the characteristics, such as the leadership style of key policy makers.
A Study on Costs, Risks and Competitiveness of Palm Oil Fruit Dealers’ Business in Malaysia
Authors: Che Omar Ahmad Raflis , Ishak Suraiya , Awang Abd Hair , Hussain Mohd Yusof
Published: May 2018

This exploratory study aims to describe the nature of palm oil intermediary business focusing on the costs structure,risks and competitive challenges. This study employs qualitative research design. Five fruit dealers (FD) are involvein the interview. The findings show that palm oil fruit dealer business requires enormous amount of cash andequipment investments during the start-up and growth stages. In addition, FDs must comply with specificrequirements to apply for the operating license. The risks are divided into non-controllable and controllable risks.The non-controllable risk refers to the external source of risks such as fresh fruit bunch (FFB) shrinkage due toweather factor, volatility of market price and inconsistent mills purchase decisions. Meanwhile, the controllable riskconsist of the probability of unripe FFB purchased from the smallholders. Furthermore, the finding indicates that thebusiness competitive structure is relatively intense due to strong bargaining power of buyers and sellers, high servicesubstitutability from nearby FDs, high rivalry among existing firms, and the need of special equipment. However, thethreat of new entrants is low due to the high entrance and exit barriers of the business. Finding of this studysuggested that agriculture intermediaries have important roles within the palm oil smallholders’ value chain.Therefore, this study disseminates preliminary insights on FDs’ business in terms of costs, risks and challenges.
The Effect of Comparative FonF Structure on Learning L2 Verb Components
Authors: Parvizi Gholam Reza
Published: May 2018

This study focuses on the impact of the type of form-focused instruction (FFI) on its efficiency in mastering L2forms. The hypothesis that FFI, which induces structural and metalinguistic salience on the basis of contrastiveanalysis of the learner’s L1 and L2, would be particularly effective at facilitating the acquisition of difficult L2 formswas tested in a quasi-experimental study comparing the effectiveness of two types of FFI, one with and one without acontrastive component. The contrastive FFI explicitly drew learners’ attention to the cross-linguistic differences inthe tense-aspect systems of their L2 and L1 while the non-contrastive treatment only focused on the tense-aspectsystem of the L2. The effects of these two types of FFI were assessed by analyzing the learners’ pre-test and post-testperformance on two tasks differing in the extent to which they involve the activation of explicit and implicitlinguistic knowledge: a grammatical judgment task and a controlled translation task. The subjects of the studycomprised of 43 students majoring in English language in the Iranian capital university, Tehran, 22 were selected asfor experimental group and 21 for control group randomly. The results of the study revealed that the quantitativeanalysis of the Grammatical Judgment Test (GJT) data indicated no significant effect of CFFI due to the novelty ofthe translatory technique, or the potential individual differences in the learning orientation of the learners. On thecontrary, the qualitative analysis indicated differential effects of this type of FFI according to the nature of targetform, i.e. CFFI was beneficial in raising the grammatical judgment of Persian Learners of English (PLE) regardingpresent perfect form but not effective in their judgment of ungrammatical progressive forms. In terms of translationtask, the CFFI appeared to be effective in the correct use of the target structures by PLE. This may be mainly due tothe fact that Translation Test (TT) needed explicit knowledge which was presented in CFFI and that translation is acontrastive activity in nature.
Autonomie met perspectief. Een terreinverkenning voor toekomstige relaties van Caribische landen met Nederland en Europa
Authors: Hirsch Ballin E.M.H.
Published: May 2018

Autonomie met perspectief. Een terreinverkenning voor toekomstige relaties van Caribische landen met Nederland en Europa

Gedurende zijn lezing aan de University of Curaçao op 2 oktober 2017, stond prof. dr. E.M.H. Hirsch Ballin stil bij de relaties van Caribische landen met Europa, in het bijzonder met Nederland, en bij de rol van het Statuut.
Reactie en naschrift op het artikel ‘Alcohol en drugs in het weg-, vlieg- en vaarverkeer’ van mr. W.A.M. Hu-a-ng
Authors: de Doelder H.
Published: May 2018

Reactie en naschrift op het artikel ‘Alcohol en drugs in het weg-, vlieg- en vaarverkeer’ van mr. W.A.M. Hu-a-ng

Reactie en naschrift op het artikel ‘Alcohol en drugs in het weg-, vlieg- en vaarverkeer’ van mr. W.A.M. Hu-a-ng.
De (aangepaste) straffen voor zedendelicten in het Curaçaose strafrecht bekeken
Authors: Murray M.F.
Published: May 2018

De (aangepaste) straffen voor zedendelicten in het Curaçaose strafrecht bekeken

Naar aanleiding van een mediagevoelige uitspraak in een zedenzaak is in Curaçao een discussie ontstaan over de hoogte van de maximale straffen op zedendelicten. In de discussie stond centraal in hoeverre de maximale straffen op zedendelicten voldoende hoog zijn. In deze bijdrage zal ingegaan worden op het feitelijk relaas van de zedenzaak evenals de herkomst van de thans geldende maximale straffen op zedendelicten.
Projektowanie krajobrazu pracy. Między praktyczną a krytyczną antropologią projektowania
Authors: Gądecki Jacek
Published: May 2018

The article attempts to answer the question concerning the role anthropological reflection plays and should play in designing the work environment, or, more broadly – the workplace landscape. Drawing on Tim Ingold’s distinction between design anthropology and design ethnography, I offer an analysis of contemporary workplace landscapes and the practices of their design based on my own research experience. In doing so, I focus on two principal, i.e. “practical” and “critical”, elements of involvement of anthropology in these processes. The first case study concerns the practices of teleworkers and the question of reconciling their professional and private lives in the limited space of their homes in general, and dividing the space of home into the sphere of working and private life in particular. The second study (in which I am involved as an independent consultant working on a team designing the working style of a company) is concerned with the design of working space in a new building planned as a showcase of the firm called X.
Lepsze życie śmieci? Design i upcykling
Authors: Izdebska Karolina
Published: May 2018

This paper is written to present the usage of waste materials in modern design. At the beginning the author analyzes the sources of fascination with waste and trash in art. Then the phenomenon from the borderline of ecology, design and high art - upcycling (re-design) is described. Upcycling was introduced as a one of the methods to maintain the environment without doing any harm and to recreate useful products out of waste materials. By changing functions, uses, and meanings of old things designers give the product a new higher value. The author lists the values and advantages of this method and examples of using it in indoor and outdoor spaces and also in fashion. In the summary the social aspects of upcycling are presented.
Moda jako źródło cierpień: etyczny wymiar produkcji i obrazowania
Authors: Milczarczyk Paula
Published: May 2018

Fashion, both in its manufacturing dimension and as a field of visual culture, remains morally involved. The article is an attempt to incorporate phenomena related to fashion in an ethical perspective. The first part of the article focuses on mass production practices: such as shipping, greenwashing, fur farm industry, or the negative environmental impact associated with production. The second part of the article is devoted to the practices related to the culture-producing dimension of fashion, as well as the total aesthetization of everyday life (and the resulting anesthetization), the falsification and the simularization of reality or fashion projects based on the use of motives rooted in culture or religion.
Co design może zdziałać? Dom jako zespół relacji
Authors: Kuhr Kamil
Published: May 2018

An interpretation of „Better Shelter” by Ikea provides a point of departure for cultural analysis of the term „home”. By asking what design can do and how it affects different understandings of home territories, I prove that common meaning of „home” is a justification for the antagonistic division into us and them. As an alternative, I suggest that home territories should be seen as performative spaces (David Morley). I analyze „The Microbial Home” with reference to Judith Butler’s theory of bodies-as-living-set-of-relations in order to show that homes are analogous sets-of-relations. In this context, design would be a way of thinking that creates inclusive spaces and addresses social issues (i.e. global migrations, environmental degradation).
Dzika strona Ulicy. Lou Reed i Walk on the Wild Side
Authors: Czubaj Mariusz
Published: May 2018

The article discusses Lou Reed's "Walk On the Wild Side" - one of the
most important songs in rock music history. Out of ethnographic
insight on New York Lou Reed creates a story of the '60s, where - in
opposition to a hippie utopia - the rational "money philosophy"
dominates. Lou Reed also invites new actors of the big city life to
the story, playing with pop culture consumer's taste and breaking its
taboo.
Warszawska piosenka z adresem (około 1930 r.). Książka adresowa i plan miasta
Authors: Piotrowski Igor
Published: May 2018

The article concerns the analysis of a special kind of the twentieth-century song described by ZbigniewAdrjański as a "Warsaw song with an address", its genesis and genre links. A key point is the reference to the city from the songs to the knowledge gathered in the Warsaw address books and city plans, the aim was to sketch a few thematic maps of the capital, which emerged from the analysis.
A jeśli nie "wrocławska piosenka", to co?
Authors: Grębowiec Jacek
Published: May 2018

The topic of the article is music that is strongly connected to the history of post-war, Polish again, Wroclaw — the city and its cultural, social and political landscape. This includes not only songs composed by artists from Wroclaw, but also songs dedicated to this city. In the article, songs from different timespans are analysed: the ones composed in the 1950s, in the pioneering period of restoration, as well as countercultural songs from the 1980s. The paper is complemented by an analysis of the newest songs that pretend to be hits or anthems of Wroclaw, although they have never gained the same fame as classical songs written by Maria Koterbska or new-wave band Klaus Mitffoch.
Od subkultury do kultury DIY. Miejskie ewolucje kultury punk
Authors: Rauszer Michał
Published: May 2018

The aim of this article is to show evolution of punk subculture in the context of a city. The author presents his ethnographical research on punk subculture. Punk is depicted as a two-figure movement. First figure works as a historical reconstruction of early punk contestation character. Second, based on late political engagement, creates a figure of alternative culture in a city. The author describes forms of engagement in movement and reconstructs the line of punk city network.
„Na kwadracie i na jego obwodzie”. Ursynowski rap lat 90.: konfrontacje, identyfikacje, aspiracje
Authors: Kubkowski Piotr
Published: May 2018

The text is an attempt to define the relationship between the urban space of Ursynów housing estates and the early works of Polish rap created in this district. The first Warsaw rappers were coevals of the district (born in late 70. and early 80.), also their nicknames were borrowed from the elements of its space, and most of the songs – in which they imitate the practices of black American rappers – were also devoted to Ursynów. Nevertheless, a crack in this narrative can be observed – the artists mostly origin from good families, their sterile auto-creations seem not to be compatible with American rap stereotypes as imitated. The author follows and interprets these narrative discontinuities.
Betty Friedan, Jane Jacobs, Richard Sennett and the 1960s’ Challenge to the Suburban Era Mystique of Security and Order
Authors: Skurowski Piotr
Published: May 2018

The paper examines and compares some of the 1960s’ most representative expressions of social critique: Betty Friedan’s The Feminine Mystique, Jane Jacobs’s The Death and Life of Great American Cities and Richard Sennett’s The Uses of Disorder, in an attempt to demonstrate how each of those intellectuals, social critics and visionaries, in their own distinct way, called for a radical departure from the established notions of the social and spatial order amidst the growing public fears of insecurity stimulated by the rising crime rate, the spread of racism and xenophobia, and the continuing “white flight” to the suburbs.
“Uncanny Domesticity” in Contemporary American Fiction: The Case of Jhumpa Lahiri
Authors: Šesnić Jelena
Published: May 2018

The argument contends that Jhumpa Lahiri’s fiction – in particular her two novels to date, The Namesake (2003) and The Lowlands (2013) – features a combination of the elements of homeliness and estrangement, domestic and foreign, ultimately, self and the other, that evokes the Freudian concept of the uncanny. Placing it in the context of the diasporic family dynamics, prevalent in Lahiri’s fiction, the uncanny effect may be seen to reside in the unspoken secrets and repressed content passed on from the first to the second generation and disturbing the neat acquisition of the trappings of middle-class domesticity. Drawing on recent models of the “geopolitical novel” (Irr), the “new immigrant fiction” (Koshy) and the “South Asian diasporic novel” (Grewal), the reading engages with the irruption of the unhomely into the domestic space, sustained by immigrant families in the face of local and global disturbances.
A obsolescência da literatura de cordel: aspectos de escrita e oralidade
Authors: Valente Junior Valdemar
Published: May 2018

Este texto visa discutir a importância da literatura de cordel como elemento cultural arcaico ainda presente na cultura brasileira contemporânea. Na condição de parte integrante da cultura nordestina, tende a estabelecer uma relação estreita com seu povo, mas esbarra na inviabilidade artesanal de sua produção na atualidade. O crescimento do nível de interesse acerca da literatura de cordel em diferentes áreas dos estudos acadêmicos resulta da necessidade do cotejo dos elementos fundadores da cultura nordestina com o processo de globalização que abrange aspectos arcaicos e modernos a partir de um mesmo fluxo.
A poética popular e social de Patativa do Assaré
Authors: Nogueira Renata Carvalho
Published: May 2018

O propósito do presente artigo é apresentar uma leitura da poética de Patativa do Assaré, partindo de um estudo do seu caráter popular e social. Sendo agricultor no interior do Ceará, o poeta observou e vivenciou a dramática realidade da região nordestina, reconhecendo-se, dessa forma, como porta-voz de seu povo. A poética patativana é marcada por um claro eixo antagônico, no qual a temática social e popular se configura segundo oposições de classes. Com base em tal premissa, propomos uma análise da poesia matuta de Patativa do Assaré, ainda pouco debatida nos meios acadêmicos.
Dupla vedação em silagem de milho na produção de bovinos confinados
Authors:   Universidade Estadual do Centro Oeste, Neumann Mikael , Leão Guilherme Fernando Mattos ,   Universidade Federal do Paraná, Santos Leslei Caroline dos , Marafon Fabiano , Askel Eloize Jaqueline
Published: May 2018

O sucesso do sistema de produção de bovinos de corte tem como alicerce a produção de volumoso de qualidade, visto que impacta no maior ou menor desempenho produtivo dos animais e, consequentemente, no retorno econômico ao pecuarista. Nesse contexto, o objetivo do presente estudo foi avaliar o desempenho produtivo, comportamento ingestivo e características de carcaça e dos componentes não-carcaça de novilhos confinados recebendo silagem de milho submetida a dois tipos de vedação, sendo: VC – silagem de milho conservada com polietileno tipo dupla face com espessura de 110 μm (vedação convencional) e DV – silagem de milho conservada com polietileno tipo dupla face com espessura de 110 μm sobreposto a outro polietileno translúcido com espessura de 110 μm (dupla vedação). A determinação da relação volumoso concentrado revelou que o sistema com dupla vedação favoreceu a menor participação da fração concentrada neste tratamento (45,4 vs 48,3%) com consequente aumento no consumo de matéria seca diário e em relação ao peso vivo (10,04 vs 9,28 kg), (2,30 vs 2,21%), respectivamente, e aumento no ganho diário de peso vivo (1,810 vs 1,565 kg). Quanto a avaliação comportamental dos novilhos, aqueles que receberam silagem com sistema de dupla vedação passaram menos tempo em alimentação (3,52 vs 4,60 horas dia-1) e em ruminação (7,07 vs 7,94 horas dia-1) e mais tempo em ócio (13,22 vs 11,28 horas-1). Em relação as características de carcaça e os componentes não-integrantes de carcaça, não houve diferença estatística entre os tratamentos. Novilhos que receberam silagem com sistema de dupla vedação apresentaram melhor desempenho produtivo.
DRINKING FOR SPEAKING: THE MULTIMODAL ORGANIZATION OF DRINKING IN CONVERSATION
Authors: M. Hoey Elliott
Published: May 2018

This article focuses on the coordination of speaking and drinking. Because physiological constraints largely preclude speaking and drinking concurrently, participants must balance their engagement in one with the other. I focus on environments in which a currently drinking participant is selected to speak next, since this requires the participant to manage the conflict between drinking now and speaking next. Participants are shown either upholding the progressive development of drinking and talk-in-interaction in parallel, or adjusting the trajectory of drinking to engage in talk-in-interaction. These orientations to the practical incompatibility between drinking and speaking reveal participants’ sensitivities to action modality.
LEARNING TO SAY GRACE
Authors: Greer Tim
Published: May 2018

Based on a detailed analysis of four naturally occurring dinner-table conversations video-recorded over a period of three weeks, this study uses longitudinal Conversation Analysis to track an outsider's growing involvement in the family ritual of praying before each meal. Through a detailed turn-by-turn account, the analysis demonstrates how the visitor moves from peripheral observation to more active participation, suggesting that his involvement in learning to say grace was one way he adapted his interactional and cultural practices to align with those of the host family. The analysis also considers the role of other family members in inviting participation and reprimanding non-normative behaviour.
Crystallization and structure analysis of the core motif of the Pks13 acyltransferase domain from Mycobacterium tuberculosis
Authors: Yu Mingjing , Dou Chao , Gu Yijun , Cheng Wei
Published: May 2018

Type I polyketide synthase 13 (Pks13) is involved in the final step of the biosynthesis of mycolic acid in Mycobacterium tuberculosis. Recent articles have reported that Pks13 is an essential enzyme in the mycolic acid biosynthesis pathway, and it has been deeply studied as a drug target in Tuberculosis. We report a high-resolution structure of the acyltransferase (AT) domain of Pks13 at 2.59 Å resolution. Structural comparison with the full-length AT domain (PDB code, 3TZW, and 3TZZ) reveals a different orientation of the C-terminal helix and rearrangement of some conserved residues.
Enhanced result on stability analysis of randomly occurring uncertain parameters, leakage, and impulsive BAM neural networks with time‐varying delays: Discrete‐time case
Authors: Sowmiya C. , Raja R. , Cao Jinde , Rajchakit G.
Published: May 2018

In real‐world problems, neural networks play an increasingly important role in terms of both theory and applications. In this paper, the asymptotic stability analysis issue is investigated for uncertain impulsive discrete‐time bidirectional associative memory neural networks with leakage and time‐varying delays. With the assistance of novel summation inequality, reciprocally convex combination technique, and triple Lyapunov‐Krasovskii functionals terms, many cases of time‐varying delays are examined to certify the stability of neural networks. Here, the uncertainties are considered as a randomly occurring parameter uncertainty, and it conforms certain mutually uncorrelated Bernoulli‐distributed white noise sequences. An important feature of the results reported here is that the probability of occurrence of the parameter uncertainties specify a priori estimate. Finally, numerical examples are proposed to expose the capability and efficiency of our research work with the help of the LMI control toolbox in MATLAB.
Tissue Engineering at the Blood‐Contacting Surface: A Review of Challenges and Strategies in Vascular Graft Development
Authors: Radke Daniel , Jia Wenkai , Sharma Dhavan , Fena Kemin , Wang Guifang , Goldman Jeremy , Zhao Feng
Published: May 2018

Tissue engineered vascular grafts (TEVGs) are beginning to achieve clinical success and hold promise as a source of grafting material when donor grafts are unsuitable or unavailable. Significant technological advances have generated small‐diameter TEVGs that are mechanically stable and promote functional remodeling by regenerating host cells. However, developing a biocompatible blood‐contacting surface remains a major challenge. The TEVG luminal surface must avoid negative inflammatory responses and thrombogenesis immediately upon implantation and promote endothelialization. The surface has therefore become a primary focus for research and development efforts. The current state of TEVGs is herein reviewed with an emphasis on the blood‐contacting surface. General vascular physiology and developmental challenges and strategies are briefly described, followed by an overview of the materials currently employed in TEVGs. The use of biodegradable materials and stem cells requires careful control of graft composition, degradation behavior, and cell recruitment ability to ensure that a physiologically relevant vessel structure is ultimately achieved. The establishment of a stable monolayer of endothelial cells and the quiescence of smooth muscle cells are critical to the maintenance of patency. Several strategies to modify blood‐contacting surfaces to resist thrombosis and control cellular recruitment are reviewed, including coatings of biomimetic peptides and heparin.
Precisely Controlled Up/Down‐Conversion Liquid and Solid State Photoluminescence of Carbon Dots
Authors: Ren Junkai , Sun Jibin , Sun Xingming , Song Rui , Xie Zheng , Zhou Shuyun
Published: May 2018

In this work, an efficient strategy is proposed to obtain single‐type carbon dots with precisely controlled up/down‐conversion photoluminescence under both liquid and solid states. Tunable fluorescence from green to red color can be achieved via either changing the solvents or matrices composition, or adjusting the concentration of carbon dots. In particular, the photoluminescence of the carbon dots can be linearly modulated by adjusting the polarity of the solvent, which is attributed to the surface‐state fluorescence mechanism. That is, the increase of solvent polarity causes the decrease of the highest occupied molecular orbital–lowest unoccupied molecular orbital energy levels, and therefore leads to the bathochromic shift of fluorescent emission. Meanwhile, the as‐prepared carbon dots and their hybrids possess excellent thermal stability. Thus, the obtained carbon dots are employed into different solid matrices as multicolor phosphors to fabricate white light‐emitting diodes that are suitable for indoor lighting. In addition, the realization of precisely controlled photoluminescence from the single‐type carbon dots will have wide applications in luminescent fields.
All‐Optical and Ultrafast Tuning of Terahertz Plasmonic Metasurfaces
Authors: Cai Honglei , Huang Qiuping , Hu Xiang , Liu Yu , Fu Zhengping , Zhao Yi , He Hongchuan , Lu Yalin
Published: May 2018

Metasurfaces have been widely used to manipulate terahertz waves due to their great potential for achieving unique electromagnetic responses. However, to realize ultrafast and efficient control of the light in active metasurfaces is still a critical challenge. Here, an ultrafast tunable metasurface which consists of ion‐implanted and annealed silicon disk array is experimentally demonstrated in the terahertz range. By utilizing the optical‐pump terahertz‐probe spectroscopy, the absolute transmission modulation up to 38% is realized at the electric dipole resonance under the femtosecond pulse excitation, with a switch‐on time within 20 ps and a recovery time of 300 ps. Furthermore, a theoretical analysis that quantitatively models the time dependence of the electron–hole plasma density and the permittivity of the silicon disks is proposed. Then, the transient transmission spectra of the metasurface are numerically simulated, which agree well with the experimental performances. The silicon‐based metasurface shows significant potential in ultrafast terahertz optics.
The ‐relation and a simple method to predict how many data points are needed for relevant steady‐state detection
Authors: Nellis Chris , Hin Céline , Savara Aditya
Published: May 2018

Steady‐state detection is of vital importance for experiments and simulations in chemical engineering, as well as also other fields of science, engineering, and finance—particularly when the full timescale of interest cannot be measured or simulated. We present a breakthrough for estimating the number of data points required before successful steady‐state detection is feasible. Using an initial window of data, the method enables predicting the prerequisites for steady state detection (ppSSD), given as a number of data points. The method is shown to be accurate for data with realistic distributions (uniform, normal, and sine‐wave), and data from actual kinetic Monte Carlo simulations. Users need only to use the algebraic equations derived and provided in this work to estimate the required number of data points for relevant steady‐state detection. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3354–3359, 2018
Continued increase in lung transplantation for coal workers’ pneumoconiosis in the United States
Authors: Blackley David J. , Halldin Cara N. , Laney A. Scott
Published: May 2018

Background

Severe coal workers’ pneumoconiosis (CWP) is increasingly common, and sometimes requires lung transplantation.

Methods

Using Organ Procurement and Transplantation Network data, we updated the trend for CWP‐related lung transplants, described CWP patients who have been waitlisted but not transplanted, and characterized the primary payer of medical costs for CWP‐related and other occupational lung disease transplants.

Results

There have been at least 62 CWP‐related lung transplants; 49 (79%) occurred in the last decade. The rate of these procedures has also increased. Twenty‐seven patients were waitlisted but did not receive a transplant. Compared to other occupational lung diseases, transplants for CWP were more likely to be paid for by public insurance.

Conclusions

The increase in the frequency and rate of lung transplantation for CWP is consistent with the rising prevalence of severe CWP among U.S. coal miners. Effective exposure controls and identification of early stage CWP remain essential for protecting these workers.
Review on the adverse health effects of asbestiform antigorite, a non‐regulated asbestiform serpentine mineral
Authors: Baur Xaver
Published: May 2018

Background

Although antigorite is generally described as platy, its fibrous (asbestiform) variant is present widespread in serpentinite rocks. In addition to its primarily fibrous occurrence, asbestiform antigorite may also be formed from serpentinite with massive appearance during tunneling and mining. It is not of commercial interest, but exposure may occur in the certain environments.

Methods and Results

Detailed studies of the structural features of this antigorite type revealed characteristics closely related to those of chrysotile. Therefore, it is plausible that this serpentine mineral may present a similar health risk for exposed subjects. This is in agreement with results from clinical and animal studies, as well as in vitro experiments showing the cytotoxic, fibrogenic, and carcinogenic potential of antigorite, similar to that of chrysotile and amphibole asbestos.

Conclusions

Current evidence supports a need for an update to existing regulations to include unregulated asbestiform antigorite, similar to regulatory measures taken for asbestos.
Palladium/Acid‐Catalyzed Straightforward Allylation of Arenes using 1‐Substituted Propynes via Aryl C−H Bond Activation
Authors: Minami Yasunori , Furuya Yuki , Hiyama Tamejiro
Published: May 2018

The title reaction of heteroarenes or electron‐deficient arenes with 1‐substituted propynes took place via C(sp2)−H bond activation in arenes to give the corresponding allylarenes in a straightforward and regioselective manner. When 1,2,4,5‐tetrafluorobenzene was used, a double allylation product, bis(2‐propen‐1‐yl)tetrafluorobenzene, was isolated.
SnI4⋅(S8)2: A Novel Adduct‐Type Infrared Second‐Order Nonlinear Optical Crystal
Authors: Guo Sheng‐Ping , Chi Yang , Xue Huai‐Guo
Published: May 2018

A simple adduct from tin tetraiodide SnI4 and octasulfur S8, SnI4⋅(S8)2 (1), is obtained employing a facile reaction. The combination of Sn4+ ions with d10 electron configuration, acentric SnI4 tetrahedra, and lone‐pair effects of S8, makes 1 a phase‐matchable infrared NLO crystal with a moderate second‐harmonic generation (SHG) response and a very high laser‐induced damage threshold (LIDT), which is well confirmed by the DFT calculations.
Nanoskalige anorganische Energiematerialien aus molekularen Vorstufen bei tiefer Temperatur
Authors: Panda Chakadola , Menezes Prashanth W. , Driess Matthias
Published: May 2018

Die Niedertemperatursynthese von anorganischen Materialien und ihren Grenzflächen bietet zahlreiche Möglichkeiten für die Entwicklung und Optimierung anorganischer Materialien in der heterogenen Katalyse, um eine nachhaltige chemische Energieumwandlung oder andere Anwendungen in Energie einsparenden Bereichen zu ermöglichen. Die Verwendung geeigneter molekularer Vorstufen zur Synthese funktioneller anorganischer Nanomaterialien ermöglicht die Kontrolle über einheitliche Partikelgrößenverteilung und Stöchiometrie im Hinblick auf gewünschte chemische und physikalische Eigenschaften. In diesem Kurzaufsatz werden einige Vorteile der Verwendung molekularer Vorstufen skizziert und anhand ausgewählter Molekül‐zu‐Nanomaterialien‐Synthesen für Anwendungen auf dem Gebiet der erneuerbaren Energien im Bereich der Sauerstoffbildungsreaktion (OER), der Wasserstoffbildungsreaktion (HER) und der gesamten Wasserspaltung diskutiert.
A Versatile Dynamic Mussel‐Inspired Biointerface: From Specific Cell Behavior Modulation to Selective Cell Isolation
Authors: Liu Lei , Tian Xiaohua , Ma Yue , Duan Yuqing , Zhao Xin , Pan Guoqing
Published: May 2018

Reported here is a novel dynamic biointerface based on reversible catechol‐boronate chemistry. Biomimetically designed peptides with a catechol‐containing sequence and a cell‐binding sequence at each end were initially obtained. The mussel‐inspired peptides were then reversibly bound to a phenylboronic acid (PBA) containing polymer‐grafted substrate through sugar‐responsive catechol‐boronate interactions. The resultant biointerface is thus capable of dynamic presentation of the bioactivity (i.e. the cell‐binding sequence) by virtue of changing sugar concentrations in the system (similar to human glycemic volatility). In addition, the sugar‐responsive biointerface enables not only dynamic modulation of stem cell adhesion behaviors but also selective isolation of tumor cells. Considering the highly biomimetic nature and biological stimuli‐responsiveness, this mussel‐inspired dynamic biointerface holds great promise in both fundamental cell biology research and advanced medical applications.
NaYF4:Yb,Er/NaYF4 Core/Shell Nanocrystals with High Upconversion Luminescence Quantum Yield
Authors: Homann Christian , Krukewitt Lisa , Frenzel Florian , Grauel Bettina , Würth Christian , Resch‐Genger Ute , Haase Markus
Published: May 2018

Upconversion core/shell nanocrystals with different mean sizes ranging from 15 to 45 nm were prepared via a modified synthesis procedure based on anhydrous rare‐earth acetates. All particles consist of a core of NaYF4:Yb,Er, doped with 18 % Yb3+ and 2 % Er3+, and an inert shell of NaYF4, with the shell thickness being equal to the radius of the core particle. Absolute measurements of the photoluminescence quantum yield at a series of different excitation power densities show that the quantum yield of 45 nm core/shell particles is already very close to the quantum yield of microcrystalline upconversion phosphor powder. Smaller core/shell particles prepared by the same method show only a moderate decrease in quantum yield. The quantum yield of 15 nm core/shell particles, for instance, is reduced by a factor of three compared to the bulk upconversion phosphor at high power densities (100 W cm−2) and by approximately a factor of 10 at low power densities (1 W cm−2).
Magnetic Properties of a Terbium–[1]Ferrocenophane Complex: Analogies between Lanthanide–Ferrocenophane and Lanthanide–Bis‐phthalocyanine Complexes
Authors: Latendresse Trevor P. , Vieru Veacheslav , Wilkins Branford O. , Bhuvanesh Nattamai S. , Chibotaru Liviu F. , Nippe Michael
Published: May 2018

A rare example of an organometallic terbium single‐ion magnet is reported. A Tb3+–[1]ferrocenophane complex displays a larger barrier to magnetization reversal than its isostructural Dy3+ analogue, which is reminiscent of trends observed for lanthanide–bis‐phthalocyanine complexes. Detailed ab initio calculations support the experimental observations and suggest a significantly larger ground‐state stabilization for the non‐Kramers ion Tb3+ in the Tb complex than for the Kramers‐ion Dy3+ in the Dy complex.
The preparation of fully bio‐based flame retardant poly(lactic acid) composites containing casein
Authors: Zhang Sheng , Jin Xiaodong , Gu Xiaoyu , Chen Chen , Li Hongfei , Zhang Zongwen , Sun Jun
Published: May 2018

In this work, a bio‐based flame retardant, casein, was incorporated into poly(lactic acid) (PLA) matrix by melt compounding in order to improve the fire resistance and sustain the biodegradable character of PLA simultaneously. The fire performance of PLA composites was evaluated by limiting oxygen index, UL‐94 vertical burning, and cone calorimeter tests, respectively. The results indicated that the introduction of 20% casein increased the limiting oxygen index value of PLA composites from 20.0% to 32.2%, upgraded the UL‐94 rating from no rating to V‐0, and decreased the peak heat release rate from 779 to 639 kW/m2. The decomposition products of PLA composites were analyzed by Fourier transform infrared, and the morphology of the char after combustion was observed by scanning electron microscopy. It was suggested that casein took effects in both gas phase by releasing non‐flammable gases (such as NH3 and H2O) and condensed phase by the formation of protective char layers. However, the presence of casein in PLA induced an unavoidable deterioration in the mechanical performance. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46599.
Application of metallic phytates to poly(vinyl chloride) as efficient biobased phosphorous flame retardants
Authors: Cheng Luyao , Wu Weihong , Meng Weihua , Xu Shuo , Han Hongda , Yu Yongfang , Qu Hongqiang , Xu Jianzhong
Published: May 2018

Simple, direct precipitation was used to synthesize green, renewable, biobased flame retardants. Copper phytate (Cu–Phyt), zinc phytate, aluminum phytate, and tin phytate (Sn–Phyt) were synthesized. Thermogravimetric analysis performed in N2 revealed that the metallic phytate (M–Phyt, where M is Cu, Zn, Al, or Sn) salts showed good charring. The limiting oxygen index (LOI), cone calorimetry (CONE) test data, tensile strength, and impact toughness were measured for flexible poly(vinyl chloride) (PVC) containing 15 wt % M–Phyt salts. The PVC/Sn–Phyt LOI rose from 24.9 to 30.3%, and the PVC/Sn–Phyt mechanical properties were on par with those of the pure PVC. The CONE test results indicate that PVC/Cu–Phyt showed the lowest total smoke production (TSP) and peak heat‐release rate (pHRR) among the samples. The TSP and pHRR of PVC/Cu–Phyt were 15.77 m2 and 181.77 kW/m2, respectively, 62.63 and 44.48% lower than those of the neat PVC. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46601.
Soy‐filled polyethylene fibers for modified surface and hydrophilic characteristics
Authors: Guzdemir Ozgun , Lukubira Sam , Ogale Amod A.
Published: May 2018

By adding soy flour (soy) to linear low‐density polyethylene (LLDPE), soy‐PE fibers with enhanced hydrophilic characteristics were developed. Blends containing only soy and LLDPE had limited draw‐down, and the resulting thick fibers showed poor mechanical properties. When monoglyceride was added as a compatibilizer, thin fibers with good properties could be successfully spun due to improved dispersion of soy agglomerates in the LLDPE melt. Fibers spun from a blend containing 23/7/70 wt % of soy‐monoglyceride‐LLDPE displayed a tensile modulus and strength of 615 ± 38 and 57 ± 8 MPa, respectively. At 30% less synthetic content, these fibers still displayed mechanical properties generally comparable to those of base polyethylene fibers. Contact angle measurements showed that the soy‐based fibers had a hydrophilic surface (contact angle of 33° ± 4°). Moisture absorption studies confirmed that soy‐PE fibers gained about 20 wt % moisture in 1 h, whereas neat LLDPE fibers did not absorb any significant amount (LLDPE is hydrophobic). This hydrophilic behavior of soy‐PE fibers mimics that of natural fibers. Presence small soy agglomerates on the fiber surface also provides a textured surface and a desired tactile feel to the soy‐PE fibers, which coupled with hydrophilic behavior indicates their potential use in disposable nonwovens. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46609.
Nanoplatelet reinforcement of cavity cell walls in polymer foams using carbon dioxide supercritical fluid
Authors: Seo Hee Won , Kim Young Jun , Kim Sanghoon , Park Jungwoo , Choi Kisuk , Park In‐Kyung , Kim Taesung , Suhr Jonghwan , Kim Kwang Jin , Nam Jae‐Do
Published: May 2018

Reinforcing the cavity cell walls of polymer foams using nanoparticles can offer a new era for the property‐structure‐processing field in the development of functionalized ultra‐light components and devices manufactured from foam. When the nanoparticles are exfoliated in polymers, the viscosity substantially increases and thus mixing or foaming usually becomes almost impossible. We use CO2 supercritical fluid (CO2 SCF) for the mixing and foaming of poly(ethylene‐vinyl acetate) copolymer (EVA) with montmorillonite (MMT) nanoplatelets. The in situ evaporation of CO2 induces robust cavity cells of the EVA/MMT nanocomposite foam in a stable form of spherical shapes, which are seldom achieved by other methods. As the bubble grows and becomes stabilized in CO2 SCF, the exfoliated MMT nanoparticles are aligned at the cell walls by the Gibbs adsorption principle to minimize the surface energy at the gas–liquid interface and increase the rupture strength of the cavity walls. It is demonstrated that the developed methodology can be successfully used for foaming EVA containing high vinyl acetate (VA) content (>40%). Since EVA is too soft to construct cell walls of foam using conventional methods, the applicability of the developed methodology is extensively broadened for superior adhesion and compatibility with other materials. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46615.
Polyurethane foams from chlorinated and non‐chlorinated metathesis modified canola oil polyols
Authors: Pillai Prasanth K. S. , Li Shaojun , Bouzidi Laziz , Narine Suresh S.
Published: May 2018

The product of 1‐butene metathesis of canola triacylglycerol (CMTAG), with shortened structures, terminal double bonds (50% of the total), and oligomers (40% dimer and trimer, and 10% higher oligomers) was used to synthesize novel polyols and polyurethane foams. A non‐chlorinated (Pol‐1) and a chlorinated polyol (Pol‐2) having OH value (170 and 190 mg KOH/g, respectively) were synthesized from CMTAG by epoxidation followed by hydroxylation, and epoxidation followed by hydrogenation, respectively. Both polyols remained liquid below ambient temperature and demonstrated physical characteristics such as viscosity which allowed for the facile preparation of polyurethane foams. The foam obtained with Pol‐1 was relatively soft (∼0.32 MPa at 10% strain) and very flexible (recovery ∼90%); whereas, the foam obtained with Pol‐2 was semi‐rigid (∼1.1 MPa at 10% strain and recovery of 64%). The higher strength and rigidity of Pol‐2 foam compared to Pol‐1 foam is chiefly attributable to the effect of the bulky chlorines on the crosslink density. Importantly, this work highlights that one can improve and control jointly the mechanical properties and deformation recovery ability of bio‐based foams by combining primary functional groups, oligomers, and high molar volume molecules in the polyols. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46616.