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This paper explores the effects of pressure on the interfacial surface contacts and the performance of organic solar cells. A combination of experimental techniques and analytical/computational models is used to study the evolving surface contacts profiles that occur when compliant, semi-rigid and rigid particles are interlocked between adjacent layers in model solar cell structures. The effects of layer surface roughness and interlocked (trapped) particles are also considered along with the effects of surface energy, adhesion energy, and pressure. The results show that increased interfacial contact lengths and decreased void lengths are associated with the application of increased pressure. Increased pressure also results in significant improvements in power conversion efficiency. These improvements in power conversion efficiency are associated with the closure up of micro- and nano-voids due to the application of pressure to layers produced via spin coating and thermal evaporation. The results suggest that pressure-induced contacts can be used to enhance the performance of organic solar cells. [ABSTRACT FROM AUTHOR]

Copyright of Annali di Igiene, Medicina Preventiva e di Comunità is the property of Societa Editrice Universo s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, a combined experimental, computational, and analytical approach is used to provide new insights into the lamination of organic solar cells and light emitting devices at macro- and micro-scales. First, the effects of applied lamination force (on contact between the laminated layers) are studied. The crack driving forces associated with the interfacial cracks (at the bi-material interfaces) are estimated along with the critical interfacial crack driving forces associated with the separation of thin films, after layer transfer. The conditions for successful lamination are predicted using a combination of experiments and computational models. Guidelines are developed for the lamination of low-cost organic electronic structures. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental and theoretical/computational micro-wrinkles and buckling on the surfaces of stretchable poly-dimethylsiloxane (PDMS) coated with nano-scale Gold (Au) layers. The wrinkles and buckles are formed by the unloading of pre-stretched PDMS/ Au structure after the evaporation of nano-scale Au layers. They are then characterized using atomic force microscopy and scanning electron microscopy. The critical stresses required for wrinkling and buckling are analyzed using analytical models. The possible interfacial cracking that can occur along with film buckling is also studied using finite element simulations of the interfacial crack growth. The implications of the results are discussed for potential applications of microwrinkles and micro-buckles in stretchable electronic structures and biomedical devices. [ABSTRACT FROM AUTHOR]

The purpose of this article is to present a new iterative technique for approximating solutions of split generalized equilibrium problem and common fixed points of multivalued demicontractive mappings satisfying the gate conditions in real Hilbert spaces. Unlike the earlier results in this direction, we obtain a strong convergence result using an Armijo line search rule for determining the best appropriate step size for the next iteration. Also, our algorithm is designed in such a way that it does not require a projection onto the feasible set. We further give an analysis of the convergence rate of our method which is shown to be O (1 / t). Finally, the performances and comparisons with some existing methods are presented through numerical experiments. This result extends, generalizes and improves many of the existing related results in a unified way. [ABSTRACT FROM AUTHOR]

Copyright of Annali di Igiene, Medicina Preventiva e di Comunità is the property of Societa Editrice Universo s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the effect of sowing media on the seed germination and subsequent seedling growth of Senna fistula L. Treatments were T1 (Top soil), T2 (River sand), T3 (Grinded coconut husk) and T4 (weathered sawdust), replicated two times for seed germination. The treatments were arranged in a Completely Randomized Design (CRD) and the data generated was subjected to analysis of variance (ANOVA) at 5% level of significance, while mean separation where appropriate was done using Least Significant Difference (LSD). The different sowing media used had positive effect on the seed emergence, the seeds planted in river sand had the highest emergence percentage of 70%. The different sowing media used did not have any significant effect on the vegetative growth parameters, statistically, they had same effect on the parameters measured. Nonetheless, seedlings from river sand produced highest number of leave (20.4), seedlings from topsoil produced highest plant height and largest leaf area of l0.62 cm and 37.l4 cm² respectively. The seedlings from weathered sawdust produced the highest stem diameter of 0.79 mm, while seedlings from grinded coconut husk had lowest values for all the growth parameters measured. Therefore, it is recommended that river sand or weathered sawdust can be used to propagate Senna fistula seeds. [ABSTRACT FROM AUTHOR]

Copyright of Annali di Igiene, Medicina Preventiva e di Comunità is the property of Societa Editrice Universo s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the results of an experimental study of the adhesion between bi-material pairs that are relevant to organic light emitting devices, hybrid organic/inorganic light emitting devices, organic bulk heterojunction solar cells, and hybrid organic/inorganic solar cells on flexible substrates. Adhesion between the possible bi-material pairs is measured using force microscopy (AFM) techniques. These include: interfaces that are relevant to organic light emitting devices, hybrid organic/inorganic light emitting devices, bulk heterojunction solar cells, and hybrid combinations of titanium dioxide (TiO2) and poly(3-hexylthiophene). The results of AFM measurements are incorporated into the Derjaguin-Muller-Toporov model for the determination of adhesion energies. The implications of the results are then discussed for the design of robust organic and hybrid organic/inorganic electronic devices. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the perception of climate change among arable crop farmers in Akinyele local government area of Oyo state, Nigeria using a well-structured questionnaire for data acquisition. Descriptive and inferential (chi-square) statistics were used to analyze the data.. The study revealed that majority of the respondents (50.8%) were between the ages of 40-49years and majority of them (85.8%) are married with household size of 7-10 persons. The study further revealed that (33.3%) of the respondents had no formal education while, (42.5%) of the respondents had a farming experience of 16years and above. However, it also shows that majority of the respondents are aware of the effect and causes of climate change. Significant association exists between marital status (x² =68.426, P=0.000), family size (X² =25.777, P=0.012) and perceived effect of climate change. The study therefore recommended that the government and extension agents should enlighten the women farmers more about climate change and should also help in making them adapt excellently to climate change. [ABSTRACT FROM AUTHOR]

The study was carried out to introduce improved okra (NHAe47-4) variety to farmers in Ido Village in Ido Local Government of Oyo State using SAFE approach to agricultural extension which includes; capacity building among farmers to enable them diagnoses their problems, identify solutions and develop plans and implement them with or without support from outside. Farmers in the studied area were selected and a group was formed comprising of twelve (12) members. Sensitization and awareness creation were conducted in the study area through series of activities such as facilitating, interactive group discussions and several meetings with the farmers were held to orientate them of the improved okra variety through teaching and management techniques. Descriptive statistical tool such as frequency distribution and percentages was used to analyze the objectives. At the end of the harvesting and whole exercise, the group (farmers) was interviewed verbally to know their levels of awareness for adoption and their general view about the improved variety in relation to the normal okra variety they were used to. The farmers embraced the technology and they were actively participated through demonstration method exercise. Having known all the techniques involved in the production cycle, the farmers also tried the technology on their individual plot which served as an encouragement factor for adoption. The study thus resulted into improving the standard of living and economic enhancement of the farmers in the study area. [ABSTRACT FROM AUTHOR]

Background. Postoperative pain management is a way of reducing or eliminating pain and discomfort with minimum side-effects after surgery. Pain is a predictable and expected experience following surgery, and if not well controlled poses a major risk to the patient. Research shows that most patients suffer complications associated with postoperative pain. It is therefore important to develop approaches on how to improve knowledge of postoperative pain management among nurses. Objective. To determine the effectiveness of a teaching programme on the knowledge of postoperative pain management among nurses in the adult surgical ward of Lagos University Teaching Hospital, Nigeria. Methods. A quasi-experimental research design was conducted, and an accidental sampling technique used to select a total of 60 nurses. Probability sampling was used to divide this group into two (control n=30, experimental group n=30). Data were collected using a modified structured questionnaire, the 'Knowledge and attitudes survey regarding pain' tool. Ethical clearance was obtained from the hospital before the administration of the questionnaire. Data obtained were coded and analysed using Statistical Package for Social Sciences version 21.0 statistical software, at p=0.05 level of significance. Results. The pre-intervention mean (standard deviation) score on knowledge of postoperative pain management among participants in the control group was 1.05 (0.60) and 1.06 (0.63) in the experimental group, with a mean difference of 0.01. Following intervention, there was a rise in mean score on knowledge of postoperative pain management among the nurses in the experimental group to 1.62 (0.97), while participants in the control group had 1.05 (0.62), with a mean difference of 0.57. There were significant statistical differences between the pre- and post-intervention mean score of participants' knowledge of postoperative pain management (t=3.68, p=0.00). Conclusion. The teaching programme was effective in improving participants' knowledge of postoperative pain management. Therefore continued education on postoperative pain management is recommended for nurses who are involved in the care of postoperative patients. [ABSTRACT FROM AUTHOR]