Temporal Expression Pattern Of The Insulin-like Growth Factor Ii And Fibroblast Growth Factor Transcripts In Vian Embryogenesis

In this study, the abundance of IGF-II and bFGF transcripts was estimated in the chicken embryos using the competitive RT-PCR analysis. Significant enhancements in the abundance of IGF-II mRNA were observed at stages HH1 and 5, and a new accumulation in these levels was observed at stage HH18 in comparison to the basal levels. The abundance of bFGF mRNA increased significantly at stages HH18 and 20, followed by an upregulation in the expression of these transcripts at stage HH26. These findings provided important information about the temporal expression pattern of IGF-II and bFGF transcripts in the whole chicken embryos during in ovo development.515949955Bass, J., Oldham, J., Sharma, M., Kambadur, R., Growth factors controlling muscle development (1999) Dom. An. Endocrinol, 17, pp. 191-197Borja, A.J.M., Zeller, R., Meyers, C., Expression of alternatively spliced bFGF coding exons and antisense mRNAs during chicken embryogenesis (1993) Dev. 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Preventive screening for intracranial aneurysms

Background: Subarachnoid hemorrhage from rupture of an intracranial aneurysm (aneurysmal subarachnoid hemorrhage) is a devastating subset of stroke. Since brain damage from the initial hemorrhage is a major cause for the poor outcome after aneurysmal subarachnoid hemorrhage, prevention of aneurysmal subarachnoid hemorrhage has the highest potential to prevent poor outcome from aneurysmal subarachnoid hemorrhage. Aim: In this review, we describe the groups at high risk of aneurysmal subarachnoid hemorrhage who may benefit from preventive screening for unruptured intracranial aneurysms followed by preventive treatment of unruptured intracranial aneurysms found. Furthermore, we describe the advantages and disadvantages of screening and advise how to perform counseling on screening. Summary of review: Modeling studies show that persons with two or more affected first-degree relatives with aneurysmal subarachnoid hemorrhage and patients with autosomal dominant polycystic kidney disease (ADPKD) are candidates for screening for unruptured intracranial aneurysms. One modeling study also suggests that persons with only one affected first-degree relative with aneurysmal subarachnoid hemorrhage are also likely candidates for screening. Another group who may benefit from screening are persons ≥35 years who smoke(d) and are hypertensive, given their high lifetime risk of aneurysmal subarachnoid hemorrhage of up to 7%, but the prevalence of unruptured intracranial aneurysms in such persons and the efficiency and cost-effectiveness of screening in this group are not yet known. The ultimate goal of screening is to increase the number of quality years of life of the screening candidates, and therefore the benefits but also many downsides of screening –such as risk of incidental findings, very small unruptured intracranial aneurysms that require regular follow-up, preventive treatment with inherent risk of complications and anxiety – should be discussed with the candidate so that an informed decision can be made before intracranial vessels are imaged. Conclusions: Several groups of persons who may benefit from screening have been identified, but since these constitute only a minority of all aneurysmal subarachnoid hemorrhage patients, additional high-risk groups still need to be identified. Further research is also needed to identify persons at low or high risk of aneurysmal development and rupture within the groups identified thus far to improve the efficiency of screening. Moreover, if new medical treatment strategies that can reduce the risk of rupture of unruptured intracranial aneurysm become available, the groups of persons who may benefit from screening could increase considerably

Public Awareness of Low-Carbon Economy in Nigeria: A Case Study of Akwa Ibom State

This paper aims to examine levels of awareness and performance relating to the promotion of a Low-carbon economy (LCE) among the general public in Akwa Ibom State, Nigeria. The data and information used were derived from 600 questionnaires distributed randomly among households in North West, North East and South senatorial districts of Akwa Ibom State. The results indicate a combination of high awareness with poor understanding of LCE programmes among respondents, with the poor understanding probably due to a shortage of appropriate information from trusted sources and shortcomings in education. Respondents generally showed positive attitudes toward pro-environmental actions, such as refusing to use plastic bags, waste recycling, water and energy conservation. Apart from regulation and policies, they considered education and economic incentives as effective mechanisms to promote LCE implementation. Overall, those consulted responded favourably towards the prospect of LCE. Results of the study, at this preliminary stage, suggest that the general public in Nigeria has the potential to be a facilitator of environmental improvements in the country

Effects of Boson Dispersion in Fermion-Boson Coupled Systems

We study the nonlinear feedback in a fermion-boson system using an extension of dynamical mean-field theory and the quantum Monte Carlo method. In the perturbative regimes (weak-coupling and atomic limits) the effective interaction among fermions increases as the width of the boson dispersion increases. In the strong coupling regime away from the anti-adiabatic limit, the effective interaction decreases as we increase the width of the boson dispersion. This behavior is closely related with complete softening of the boson field. We elucidate the parameters that control this nonperturbative region where fluctuations of the dispersive bosons enhance the delocalization of fermions.Comment: 14 pages RevTeX including 12 PS figure

Applying an experimental design to improve the manufacturing process and properties of a novel sound absorber with recycled fibres from End-of-Life-Tyres

[EN] The present work analyses the acoustic properties of acoustic absorbent textile products obtained from the thermo-compression of recycled End-of-Life Tyres. The objective is to obtain products of greater added value from the waste of End-of-Life Tyres, which can become a substitute for the fibrous materials currently used as acoustic absorbents. Experimental design was used to determine the number of samples to be prepared and the manufacturing conditions to maximise acoustic absorption. Five factors were taken into account: material type, temperature, time, weight and compaction factor. The obtained results demonstrate the validity of the experimental design to select the manufacturing factors in order to improve the sound absorption of these textile waste products.Segura Alcaraz, JG.; Zamorano Cantó, M.; Miró Martínez, P.; Nadal Gisbert, AV.; Crespo, J. (2020). Applying an experimental design to improve the manufacturing process and properties of a novel sound absorber with recycled fibres from End-of-Life-Tyres. Journal of Industrial Textiles (Online). 50(1):13-22. https://doi.org/10.1177/1528083718819876S1322501Santini, A., Morselli, L., Passarini, F., Vassura, I., Di Carlo, S., & Bonino, F. (2011). End-of-Life Vehicles management: Italian material and energy recovery efficiency. Waste Management, 31(3), 489-494. doi:10.1016/j.wasman.2010.09.015Sienkiewicz, M., Kucinska-Lipka, J., Janik, H., & Balas, A. (2012). Progress in used tyres management in the European Union: A review. Waste Management, 32(10), 1742-1751. doi:10.1016/j.wasman.2012.05.010Bartl, A., Hackl, A., Mihalyi, B., Wistuba, M., & Marini, I. (2005). Recycling of Fibre Materials. Process Safety and Environmental Protection, 83(4), 351-358. doi:10.1205/psep.04392Maderuelo-Sanz, R., Nadal-Gisbert, A. V., Crespo-Amorós, J. E., & Parres-García, F. (2012). A novel sound absorber with recycled fibers coming from end of life tires (ELTs). Applied Acoustics, 73(4), 402-408. doi:10.1016/j.apacoust.2011.12.001Jimenez-Espadafor, F. J., Becerra Villanueva, J. A., García, M. T., Trujillo, E. C., & Blanco, A. M. (2011). Optimal design of acoustic material from tire fluff. Materials & Design, 32(6), 3608-3616. doi:10.1016/j.matdes.2011.02.024Parres, F., Crespo-Amorós, J. E., Nadal-Gisbert, A., & Navarro, R. (2012). Mechanical and Thermal Properties Analysis of Polypropylene Reinforced with Polyamide Microfibre Obtained from Shredded Tyres. Polymers and Polymer Composites, 20(9), 817-822. doi:10.1177/096739111202000907Maderuelo-Sanz, R., Martín-Castizo, M., & Vílchez-Gómez, R. (2011). The performance of resilient layers made from recycled rubber fluff for impact noise reduction. Applied Acoustics, 72(11), 823-828. doi:10.1016/j.apacoust.2011.05.004Castagnède, B., Aknine, A., Brouard, B., & Tarnow, V. (2000). Effects of compression on the sound absorption of fibrous materials. Applied Acoustics, 61(2), 173-182. doi:10.1016/s0003-682x(00)00003-7Lou, C.-W., Lin, J.-H., & Su, K.-H. (2005). Recycling Polyester and Polypropylene Nonwoven Selvages to Produce Functional Sound Absorption Composites. Textile Research Journal, 75(5), 390-394. doi:10.1177/0040517505054178Seddeq, H. S., Aly, N. M., Marwa A, A., & Elshakankery, M. (2012). Investigation on sound absorption properties for recycled fibrous materials. Journal of Industrial Textiles, 43(1), 56-73. doi:10.1177/1528083712446956Sun, Z., Shen, Z., Ma, S., & Zhang, X. (2013). Novel Application of Glass Fibers Recovered From Waste Printed Circuit Boards as Sound and Thermal Insulation Material. Journal of Materials Engineering and Performance, 22(10), 3140-3146. doi:10.1007/s11665-013-0587-yRushforth, I. M., Horoshenkov, K. V., Miraftab, M., & Swift, M. J. (2005). Impact sound insulation and viscoelastic properties of underlay manufactured from recycled carpet waste. Applied Acoustics, 66(6), 731-749. doi:10.1016/j.apacoust.2004.10.00

Characterization of the resistance to Phytophthora infestans in local potato cultivars in Bolivia

This experiment was carried out to investigate whether and how much field resistance to late blight, caused by Phytophthora infestans, is present in the local cultivated potato germplasm. In total 36 entries were compared in a field experiment in an area highly conducive to late blight development. Of the 36 cultivars 32 were local cultivars belonging to five Solanum species, S. tuberosum (1 accession), S. andigena (18), S. juzepczukii (2), S. stenotomum (9) and S. ajanhuiri (2). The other four cultivars were derived from breeding programmes, one being the Dutch cultivar Alpha used as a highly susceptible control. The 36 cultivars were planted according to a simple 6 × 6 lattice design with three replicates. Each replicate was divided in six incomplete blocks each with six cultivars. The disease severity was assessed weekly during 9 weeks starting 48 days after planting. The area under the disease progress curve (AUDPC) was used as a measure of the field resistance. Nine isolates from surrounding potato fields were tested for their virulence to the resistance genes R1¿R11 using 22 differential cultivars. The components of the field resistance of 19 of these cultivars were compared in the greenhouse using a local isolate with virulence to all known R-genes, except to R9. The nine isolates represented seven races with a race complexity varying from 7 to 10 virulence factors. All isolates carried virulence against R1, R2, R3, R7, R10 and R11, while virulence against R9 was absent. The AUDPC among the 32 local cultivars ranged from very large, significantly larger than that of `Alpha¿ to very small. The AUDPC from S. stenotomum accessions ranged from very large to intermediate, those from S. andigena accessions from large to very small. Especially among the S. andigena accessions interesting levels of field resistance were found. Four components of field resistance were assessed, latency period (LP), lesion size (LS), lesion growth rate (LGR) and relative sporulation area (RSA). All four showed a considerable variation among the cultivars. The LP ranged from 3½ to 6 days. The LS ranged from 225 mm2 to 20 mm2. The LGR varied about six-fold, the RSA more than 10-fold. The components tended to vary in association with one another. LP and LGR were well associated with each other and had a significant correlation with the AUDPC

Panels of eco-friendly materials for architectural acoustics

[EN] The objective of this work is to study the acoustic and mechanical properties of environmentally friendly materials manufactured through the process of resin infusion made from different types of fibres: some are biodegradable obtained from renewable resources and others from recycled textile waste. The materials studied are composed of fibres of jute, hemp, coconut, biaxial linen and textile waste. The modulus of elasticity and the airborne sound insulation are determined through dynamic and acoustic tests, respectively. The behaviour of these innovative materials is compared to some traditional materials commonly used in architectural acoustics. The acoustic study of these environmentally friendly materials is carried out considering them as light elements of a single layer for their application to insulation of walls. The results are compared to plasterboards, considered as the most commonly used light material in buildings for airborne sound insulation. In conclusion, these materials are a real and effective alternative to the traditional composites of synthetic matrices and reinforcements of glass fibres and there is a reduction in the production cost compared to the usual porous synthetic media that have expensive production processes.Fontoba-Ferrándiz, J.; Juliá Sanchis, E.; Crespo, J.; Segura Alcaraz, JG.; Gadea Borrell, JM.; Parres, F. (2020). Panels of eco-friendly materials for architectural acoustics. Journal of Composite Materials. 54(25):3743-3753. https://doi.org/10.1177/0021998320918914S374337535425Yahya, M. N., Sambu, M., Latif, H. A., & Junaid, T. M. (2017). A study of Acoustics Performance on Natural Fibre Composite. IOP Conference Series: Materials Science and Engineering, 226, 012013. doi:10.1088/1757-899x/226/1/012013Putra, A., Or, K. H., Selamat, M. Z., Nor, M. J. M., Hassan, M. H., & Prasetiyo, I. (2018). Sound absorption of extracted pineapple-leaf fibres. Applied Acoustics, 136, 9-15. doi:10.1016/j.apacoust.2018.01.029Dunne, R., Desai, D., & Sadiku, R. (2017). Material characterization of blended sisal-kenaf composites with an ABS matrix. Applied Acoustics, 125, 184-193. doi:10.1016/j.apacoust.2017.03.022Mohanty, A. K., Misra, M., & Hinrichsen, G. (2000). Biofibres, biodegradable polymers and biocomposites: An overview. Macromolecular Materials and Engineering, 276-277(1), 1-24. doi:10.1002/(sici)1439-2054(20000301)276:13.0.co;2-wLuckachan, G. E., & Pillai, C. K. S. (2011). Biodegradable Polymers- A Review on Recent Trends and Emerging Perspectives. Journal of Polymers and the Environment, 19(3), 637-676. doi:10.1007/s10924-011-0317-1Belakroum, R., Gherfi, A., Kadja, M., Maalouf, C., Lachi, M., El Wakil, N., & Mai, T. H. (2018). Design and properties of a new sustainable construction material based on date palm fibers and lime. Construction and Building Materials, 184, 330-343. doi:10.1016/j.conbuildmat.2018.06.196Sèbe, G. (2000). Applied Composite Materials, 7(5/6), 341-349. doi:10.1023/a:1026538107200Yates, M. R., & Barlow, C. Y. (2013). Life cycle assessments of biodegradable, commercial biopolymers—A critical review. Resources, Conservation and Recycling, 78, 54-66. doi:10.1016/j.resconrec.2013.06.010Rouison, D., Sain, M., & Couturier, M. (2006). Resin transfer molding of hemp fiber composites: optimization of the process and mechanical properties of the materials. Composites Science and Technology, 66(7-8), 895-906. doi:10.1016/j.compscitech.2005.07.040Sreekumar, P. A., Joseph, K., Unnikrishnan, G., & Thomas, S. (2007). A comparative study on mechanical properties of sisal-leaf fibre-reinforced polyester composites prepared by resin transfer and compression moulding techniques. Composites Science and Technology, 67(3-4), 453-461. doi:10.1016/j.compscitech.2006.08.025Rassmann, S., Reid, R. G., & Paskaramoorthy, R. (2010). Effects of processing conditions on the mechanical and water absorption properties of resin transfer moulded kenaf fibre reinforced polyester composite laminates. Composites Part A: Applied Science and Manufacturing, 41(11), 1612-1619. doi:10.1016/j.compositesa.2010.07.009Vijay, R., & Singaravelu, D. L. (2016). Experimental investigation on the mechanical properties ofCyperus pangoreifibers and jute fiber-based natural fiber composites. International Journal of Polymer Analysis and Characterization, 21(7), 617-627. doi:10.1080/1023666x.2016.1192354Williams, G. I. (2000). Applied Composite Materials, 7(5/6), 421-432. doi:10.1023/a:1026583404899O’Donnell, A., Dweib, M. ., & Wool, R. . (2004). Natural fiber composites with plant oil-based resin. Composites Science and Technology, 64(9), 1135-1145. doi:10.1016/j.compscitech.2003.09.024Tran, P., Graiver, D., & Narayan, R. (2006). Biocomposites synthesized from chemically modified soy oil and biofibers. Journal of Applied Polymer Science, 102(1), 69-75. doi:10.1002/app.22265Liu, Q., & Hughes, M. (2008). The fracture behaviour and toughness of woven flax fibre reinforced epoxy composites. Composites Part A: Applied Science and Manufacturing, 39(10), 1644-1652. doi:10.1016/j.compositesa.2008.07.008Scarponi, C., Pizzinelli, C. S., Sánchez-Sáez, S., & Barbero, E. (2009). Impact Load Behaviour of Resin Transfer Moulding (RTM) Hemp Fibre Composite Laminates. Journal of Biobased Materials and Bioenergy, 3(3), 298-310. doi:10.1166/jbmb.2009.1040Dahy, H. (2017). Biocomposite materials based on annual natural fibres and biopolymers – Design, fabrication and customized applications in architecture. Construction and Building Materials, 147, 212-220. doi:10.1016/j.conbuildmat.2017.04.079Saba, N., Paridah, M. T., & Jawaid, M. (2015). Mechanical properties of kenaf fibre reinforced polymer composite: A review. Construction and Building Materials, 76, 87-96. doi:10.1016/j.conbuildmat.2014.11.043Senthilkumar, K., Saba, N., Rajini, N., Chandrasekar, M., Jawaid, M., Siengchin, S., & Alotman, O. Y. (2018). Mechanical properties evaluation of sisal fibre reinforced polymer composites: A review. Construction and Building Materials, 174, 713-729. doi:10.1016/j.conbuildmat.2018.04.143Alves, C., Ferrão, P. M. C., Silva, A. J., Reis, L. G., Freitas, M., Rodrigues, L. B., & Alves, D. E. (2010). Ecodesign of automotive components making use of natural jute fiber composites. Journal of Cleaner Production, 18(4), 313-327. doi:10.1016/j.jclepro.2009.10.022Van Vuure, A. W., Baets, J., Wouters, K., & Hendrickx, K. (2015). Compressive properties of natural fibre composites. Materials Letters, 149, 138-140. doi:10.1016/j.matlet.2015.01.158Galan-Marin, C., Rivera-Gomez, C., & Garcia-Martinez, A. (2016). Use of Natural-Fiber Bio-Composites in Construction versus Traditional Solutions: Operational and Embodied Energy Assessment. Materials, 9(6), 465. doi:10.3390/ma9060465Bogoeva-Gaceva, G., Avella, M., Malinconico, M., Buzarovska, A., Grozdanov, A., Gentile, G., & Errico, M. E. (2007). Natural fiber eco-composites. Polymer Composites, 28(1), 98-107. doi:10.1002/pc.20270Peng, L., Song, B., Wang, J., & Wang, D. (2015). Mechanic and Acoustic Properties of the Sound-Absorbing Material Made from Natural Fiber and Polyester. Advances in Materials Science and Engineering, 2015, 1-5. doi:10.1155/2015/274913Benfratello, S., Capitano, C., Peri, G., Rizzo, G., Scaccianoce, G., & Sorrentino, G. (2013). Thermal and structural properties of a hemp–lime biocomposite. Construction and Building Materials, 48, 745-754. doi:10.1016/j.conbuildmat.2013.07.096Adekomaya, O., Jamiru, T., Sadiku, R., & Huan, Z. (2015). 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Gell-Mann and Low formula for degenerate unperturbed states

The Gell-Mann and Low switching allows to transform eigenstates of an unperturbed Hamiltonian $H_0$ into eigenstates of the modified Hamiltonian $H_0 + V$. This switching can be performed when the initial eigenstate is not degenerate, under some gap conditions with the remainder of the spectrum. We show here how to extend this approach to the case when the ground state of the unperturbed Hamiltonian is degenerate. More precisely, we prove that the switching procedure can still be performed when the initial states are eigenstates of the finite rank self-adjoint operator \cP_0 V \cP_0, where \cP_0 is the projection onto a degenerate eigenspace of $H_0$

Evaluation of green walls as passive acoustic insulation system for buildings

Greenery on buildings is being consolidated as an interesting way to improve the quality of life in urban environments. Among the benefits that are associated with greenery systems for buildings, such as energy savings, biodiversity support, and storm-water control, there is also noise attenuation. Despite the fact that green walls are one of the most promising building greenery systems, few studies of their sound insulation potential have been conducted. In addition, there are different types of green walls; therefore, available data for this purpose are not only sparse but also scattered. To gather knowledge about the contribution of vertical greenery systems to noise reduction, especially a modular-based green wall, two different standardised laboratory tests were conducted. The main results were a weighted sound reduction index (Rw) of 15 dB and a weighted sound absorption coefficient (a) of 0.40. It could be concluded that green walls have significant potential as a sound insulation tool for buildings but that some design adjustments should be performed, such as improving the efficiency of sealing the joints between the modular pieces.The authors would like to thank the FEDER of the European Union for financial support via the project ‘‘G-GI3000/IDIX SILENTVEG: Barreras vegetales autónomas y sostenibles para la mitigación acústica y compensación del CO2 en vías de transporte, con seguimiento telemático’’ of the ‘‘Programa Operativo FEDER de Andalucía 2007-2013’’