Damage Control Measures in Composites: Focus on Damage Tolerance of Aerospace Structures

Barely Visible Impact Damage (BVID) in composite materials presents a stealthy yet significant risk to structural integrity, particularly challenging due to its elusive nature. The approach adopted here diverges from traditional methodologies, focusing on the novel application of Digital Image Correlation (DIC) to map surface area changes during in-situ Compression After Impact (CAI) tests. This technique allows for an in-depth analysis of planar strains along the x and y axes, shedding light on the material\u27s behavior under stress. A pivotal advancement lies in developing a method for precisely identifying when BVID-induced delamination recommences. By meticulously analyzing strain pattern deviations along these axes, the onset of additional damage is accurately pinpointed, significantly improving predictive capabilities for delamination due to BVID. This approach enhances the structural integrity assessment of composite materials, bolstering safety measures. The techniques and insights gained significantly contribute to advancing maintenance strategies and structural evaluation in aerospace composites by offering refined tools for early detection of BVID-induced damage

National Action Plan for the Conservation of Marine Turtles along the Egyptian Mediterranean Coast

Marine turtles are highly migratory reptiles that utilize both terrestrial and aquatic environments during their life. As in other regions of the Mediterranean, marine turtles in Egypt are affected by numerous human activities, such as deterioration of critical habitats and migratory routes, incidental capture, boat strikes, pollution and intentional killings. In accordance with the commitment of Egypt to the conservation of marine turtles in its national waters, underlined in national legislation and by way of ratification of related international conventions, the National Action Plan for the Conservation of Marine Turtles (NAP) was developed and adopted with the support of UNEP-MAP Regional Activity Centre for Specially Protected Areas. The participatory approach was applied in the preparation of the NAP, carried out through the concentration meetings with stakeholders. The main goal of the NAP is to achieve favorable conservation status for marine turtle species and their habitats, and enhance their protection along the Egyptian Mediterranean Coast. This goal will be implemented through specific actions and sub-actions, including legislation, management, research, capacity building, and awareness and education

An Exploratory Insight into Young Tunisian Consumers Perception of Sustainable Diet

Sustainable diets are defined as diets with low environmental impacts which contribute to food and nutrition security and to healthy life for present and future generations. The objective of this research was to investigate attitudes and behaviors of young Tunisian consumers toward sustainable diet. A sample of 309 Tunisian consumers aged between 20-30 years old was surveyed online. Respondents were asked about their demographic characteristics, their diet, and their concerns about environment and sustainability. Results showed that 91.6%25 of respondents expressed their interest to environmental issues. For 70.6%25 whenever it is possible, they declared adopting a sustainable diet. However, 17.8 %25 of respondents believed that a sustainable diet is expensive and this is dedicated to consumers with financial resources%253A this highlighted a misunderstanding related to different dimensions of sustainable diet. In this context, further efforts through education and communication need to be conducte

Estimación de la proporción de sexos de crías de tortugas marinas caguama, mediante la duración de incubación y temperatura de los nidos en las playas de Sirte (Libia)

Hatchling sex ratios in loggerhead marine turtles (Caretta caretta) were estimated on the beaches near Sirte (Libya), using two methods: incubation duration and nest mean temperature during the middle third of the incubation period. Electronic temperature/humidity loggers were deployed at a total of 13 selected nests at Al-Ghbeba, Al-Thalateen, west of Al- Thalateen, Shash and Al-Arbaeen. The incubation period ranged from 47 to 58 days and average temperature ranged from 29°C to 31.8°C. The maximum temperature during this period increased to between 0.6°C and 3.5°C, while the mean temperature also increased during the middle third of the incubation period compared with the first third and continued to increase during the last third. As expected, this study showed that the temperature in the nest decreased with increasing depth of the nest. The results showed a female-dominated sex ratio at 85.4% on the basis of incubation duration and 70.4% on the basis of mean temperature. These findings support the reported highly female-skewed sex ratios in the Mediterranean and elsewhere.Se ha efectuado una estimación de proporción de sexos en las crías de tortugas marinas caguama (Caretta caretta) en las playas cerca de Sirte (Libia) utilizando dos métodos: la duración de la incubación y la temperatura media del nido durante el segundo tercio del período de incubación. Se registraron electrónicamente los valores de temperatura/humedad en un total de 13 nidos seleccionados en Al-Ghbeba, Al-Thalateen, zona oeste de Al-Thalateen, Shash y Al-Arbaeen. El período de incubación varió desde 47 hasta 58 días y la temperatura media osciló desde 29 hasta 31.8°C. La temperatura máxima durante este período aumentó entre 0,6 y 3.5°C, mientras que la temperatura media también aumentó durante el segundo tercio del período de incubación en comparación con el primer tercio y siguió aumentando durante el último tercio. Como era de esperar, este estudio mostró que la temperatura en el nido disminuyó con el aumento de la profundidad de la jerarquía. Los resultados basados en la duración de la incubación mostraron una sex-ratio en favor de las hembras del 85.4%, mientras que este valor fue del 70.4% si los resultados se basaban en la temperatura media. Estos datos concuerdan con los estudios efectuados en el Mediterráneo y en otras zonas, en los que se aprecia una sex-ratio altamente sesgada en favor de las hembras

Kaposi sarcoma in an HIV-negative Tunisian patient: A rare cause of metatarsalgia

AbstractBackgroundKaposi sarcoma (KS) is an angioproliferative neoplasm that is commonly associated with human herpes virus-8 (HHV-8) and human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). KS with osseous involvement is a rare occurrence, and is far more common in acquired immunodeficiency syndrome (AIDS)-related KS.Case presentationWe present a 32-year-old Tunisian man, HIV negative, who presented with a 4-year history of atraumatic mechanical metatarsalgia that progressively worsened with a limping gait. Physical examination revealed marked symmetrical forefoot lymphedema and a painful restricted left knee joint movement. Physical examination showed purple-blue plaques and nodules on the feet and ankles. Serologic tests for HIV and syphilis were negative. Plain radiography of the feet revealed numerous small lytic lesions. There were also scattered lytic lesions in the metaphysis of the proximal tibia and fibula. Osteolysis was predominantly left. Magnetic resonance imaging of the feet showed abnormal bone marrow signal of metatarsals and phalanges. Skin lesion biopsy yielded the diagnosis of Kaposi sarcoma. The disease was managed with chemotherapy including vinblastine.ConclusionIn a patient presenting with metatarsalgia without a commonly detected cause, it is mandatory to search for other lesions that may point to a rare diagnosis as KS which is famous for involvement of the metatarsal bone

Molecular prevalence of Chlamydia and Chlamydia-like bacteria in Tunisian domestic ruminant farms and their influencing risk factors

Chlamydia and Chlamydia-like bacteria are well known to infect several organisms and may cause a wide range of diseases, particularly in ruminants. To gain insight into the prevalence and diversity of these intracellular bacteria, we applied a pan-Chlamydiales real-time PCR to 1,134 veterinary samples taken from 130 Tunisian ruminant herds. The true adjusted animal population-level prevalence was 12.9% in cattle, against 8.7% in sheep. In addition, the true adjusted herd-level prevalence of Chlamydiae was 80% in cattle and 25.5% in sheep. Chlamydiales from three familylevel lineages were detected indicating a high biodiversity of Chlamydiales in ruminant herds. Our results showed that Parachlamydia acanthamoebae could be responsiblefor bovine and ovine chlamydiosis in central-eastern Tunisia. Multivariable logistic regression analysis at the animal population level indicated that strata and digestive disorders variables were the important risk factors of bovine and ovine chlamydiosis. However, origin and age variables were found to be associated withbovine and ovine chlamydiosis, respectively. At the herd level, risk factors for Chlamydia positivity were as follows: abortion and herd size for cattle against breeding system, cleaning frequency, quarantine, use of disinfectant and floor type for sheep. Paying attention to these risk factors will help improvement of control programs against this harmful zoonotic disease

Toward a common approach for assessing the conservation status of marine turtle species within the European marine strategy framework directive

[EN] Environmental policies, including the European Marine Strategy Framework Directive (MSFD), generally rely on the measurement of indicators to assess the good environmental status (GES) and ensure the protection of marine ecosystems. However, depending on available scientific knowledge and monitoring programs in place, quantitative GES assessments are not always feasible. This is specifically the case for marine turtle species, which are listed under the Biodiversity Descriptor of the MSFD. Relying on an expert consultation, the goal of this study was to develop indicators and a common assessment approach to be employed by European Union Member States to evaluate the status of marine turtle populations in the frame of the MSFD. A dedicated international expert group was created to explore and test potential assessment approaches, in coherence with other environmental policies (i.e. Habitats Directive, OSPAR and Barcelona Conventions). Following a series of workshops, the group provided recommendations for the GES assessment of marine turtles. In particular, indicators and assessment methods were defined, setting a solid basis for future MSFD assessments. Although knowledge gaps remain, data requirements identified in this study will guide future data collection initiatives and inform monitoring programs implemented by EU Member States. Overall this study highlights the value of international collaboration for the conservation of vulnerable species, such as marine turtles.This study was funded by the French Ministry of Environment (MTES-MNHN Conventions n degrees 2102636187 (2019) and n degrees 2102994526 (2020)). DM acknowledges support from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement n degrees 794938. The work of ADM was supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the "First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant" (Project Number: 2340). FV was supported by the Investigator Programme of the Fundacao para a Ciencia e Tecnologia (FCT, CEECIND/03469/2017, CEECIND/03426/2020).Girard, F.; Girard, A.; Monsinjon, J.; Arcangeli, A.; Belda, E.; Cardona, L.; Casale, P.... (2022). Toward a common approach for assessing the conservation status of marine turtle species within the European marine strategy framework directive. Frontiers in Marine Science. 9:1-22. https://doi.org/10.3389/fmars.2022.790733122

Nesting range expansion of loggerhead turtles in the Mediterranean: phenology, spatial distribution and conservation implications.

Global warming is affecting habitat quality and availability on our planet and some species are predicted or are by now changing their distribution range. Here we show that loggerhead turtles have already started to expand their nesting range into the Western Mediterranean, which has until recently hosted only sporadic nests. We compiled information on nesting activity from beaches surrounding the Western Mediterranean and collected metadata on loggerhead turtle nests in Spain, France, Italy, and Tunisia between 2010 and 2020 to provide an exhaustive overview on the phenomenon of emerging new nest sites for loggerhead turtles. The number of recorded nests has increased drastically since 2013 from 1 to 3 nests/year to a record number of 84 registered in 2020. While this increase may partly be explained by grown awareness and reporting by citizens, there is no doubt of an upward trend in nesting activity. The nests are unevenly distributed over the study area with most nests occurring on the coasts of the warmer Tyrrhenian Sea. A hotspot analysis identified beaches in SW Italy, SE Sardinia, and NW Tunisia with statistically significant clustering of nests. Within these hotspots, three beaches in SW Italy and one in Tunisia had nests at least four out of the five last years. Nesting phenology corresponds to that of Eastern Mediterranean rookeries, and mean hatching success of naturally incubating, non-manipulated nests was 66 %, although there was variability across the region. Mean incubation durations also varied between countries indicating a diversity in inferred sex ratios, with sufficient female production to foster future colonisation of this region. Unfortunately, these beaches are already under high tourist pressure and subject to intense coastal development, imposing many threats to the females, eggs, and hatchlings. Thus, while this study reveals the unique opportunity to witness and study an ongoing new colonisation process in loggerhead turtles, it also calls for urgent proactive conservation actions to mitigate these threats and allow the turtles to establish new rookeries

Experimental study of an R1234ze(E)/R134a mixture (R450A) as R134a replacement

[EN] This work presents an experimental analysis of a non-flammable R1234ze(E)/R134a mixture (R450A) as R134a drop-in replacement. While R134a has a high GWP value (1430), the R450A GWP is only 547. The experimental tests are carried out in a vapour compression plant equipped with a variable-speed compressor. The replacement suitability has been studied combining different operating conditions: evaporation temperature, condensation temperature and the use of an internal heat exchanger (IHX). The drop-in cooling capacity of R450A compared with R134a is 6% lower as average. R450A COP is even higher to those resulting with R134a (approximately 1%). The discharge temperature of R450A is lower than that of R134a, 2K as average. The IHX has a similar positive influence on the energy performance of both fluids. In conclusion, R450A can be considered as a good candidate to replace R134a.The authors thankfully acknowledge "Ministerio de Educacion, Cultura y Deporte" for supporting this work through "Becas y Contratos de Formacion de Profesorado Universitario del Programa Nacional de Formacion de Recursos Humanos de Investigacion del ejercicio 2012".Mota Babiloni, A.; Navarro Esbri, J.; Barragán Cervera, Á.; Moles Ribera, F.; Peris Pérez, B. (2015). Experimental study of an R1234ze(E)/R134a mixture (R450A) as R134a replacement. International Journal of Refrigeration. 51:52-58. doi:10.1016/j.ijrefrig.2014.12.010S52585