Smart approaches to Aquaponics 4.0 with focus on water quality − Comprehensive review

The fast growth of the world population associated with the ever-increasing need for food and the significant contribution of agriculture to anthropogenic global warming is driving the changes from conventional farming approaches to innovative and sustainable agriculture ones. One of these approaches is aquaculture which is founded on the principle of circular economy combining aquaculture and hydroponics in symbiose with aquaculture waste serving as nutrients for plant growth. Conventional Aquaponics has evolved to Aquaponics 4.0 with a fully automated and remote-controlled system for producing foods at an industrial scale. The implementation of the Internet of Things (IoT) and Artificial Intelligence (AI) could simplify farmers’ tasks with remote operations while allowing them to achieve automatic and precise control of inputs and outputs as well as to improve the overall efficiency of the system. This review focuses on the use of these smart technologies to analyze, monitor, and maintain good water quality and appropriate replenishment in Aquaponics systems. The identified research gap and future possible contributions in this area are also discussed

A Review on Cooling Systems for Portable Energy Storage Units

Achieving the global electricity demand and meeting the United Nations sustainable development target on reliable and sustainable energy supply by 2050 are crucial. Portable energy storage (PES) units, powered by solid-state battery cells, can offer a sustainable and cost-effective solution for regions with limited power-grid access. However, operating in high-dust and high-temperature environments presents challenges that require effective thermal management solutions. This paper is a comprehensive review of thermal management systems for PES units, with a specific focus on addressing the challenge of overheating in airtight designs. The review of various active and passive cooling systems is conducted through extensive study of the relevant literature, which is significant in providing insights into the operation, performance parameters, and design options for different cooling system technologies. The findings from this review show heat pipe (HP) technologies as key cooling-system solutions for airtight PES units. Specifically, loop and oscillating HPs, as well as the vapour chamber, offer desirable features such as compactness, low cost, and high thermal conductivity that make them superior to other alternatives for the cooling systems in PES. The insights and knowledge generated via this review will help facilitate the design and development of innovative, efficient, and reliable PES units, thereby contributing to the advancement of off-grid renewable energy applications and enabling sustainable power solutions worldwide. Furthermore, an appropriate design of PES units can help in reducing capital and maintenance costs

Wind Flow and Its Interaction with a Mobile Solar PV System Mounted on a Trailer

Efficient implementation of clean energy technologies is paramount, with mobile solar PV systems on trailers (MSPTs) emerging as pivotal solutions, particularly in regions with limited power grid access. This endeavour is vital for meeting escalating electricity demands and aligning with the UN Sustainable Development Goal (SDG), aimed at ensuring dependable and sustainable energy provision in developing countries. This study investigates the aerodynamic behaviour of a designed MSPT using numerical simulation and experimental methods, thereby offering optimization potential for MSPT design and enhancing overall performance and reliability. Specifically, the study focuses on the effects of wind velocity and tilt angles on the drag and lift forces, as well as drag and lift coefficients on the panel used in the MSPT system. The overall wind force on the entire MSPT, including nine large solar PV panels, is scrutinised, considering combined wind flow and system geometry effects. The numerical investigations were conducted using ANSYS-Fluent software (version 2022/R2) and experimental testing was performed within the C15-10 Wind Tunnel, utilizing scaled-down models to validate the accuracy of the simulation. The findings from the numerical investigations showed an increased turbulence caused by gaps between panels, resulting in almost 62% higher suction flow velocity and 22% higher suction pressure compared to a single panel. Drag and lift forces on the entire MSPT were approximately 6.7 and 7.8 times greater than those on a single panel with the same 30-degree tilt angle, respectively. The findings revealed that scaling forces on a single panel is insufficient for accurately predicting the aerodynamic forces on the entire MSPT. The insights and the knowledge from this study pave the way for further improvements in mobile solar PV technology

Use of the socio-ecological model to explore factors that influence the implementation of a diabetes structured education programme (EXTEND project) in Lilongwe, Malawi and Maputo, Mozambique : a qualitative study

Background: Diabetes Self-Management Education and Support (DSMES) programmes are vital for type 2 diabetes mellitus (T2DM) management. However, they are limited in Sub-Saharan Africa (SSA). To address this gap, a DSMES, namedEXTEND was developed in Lilongwe (Malawi) and Maputo (Mozambique). This qualitative study aimed to explore factors that influence the implementation of DSMES in these settings. Methods: The Socio-ecological model was applied to explore factors influencing the implementation of DSMES in SSA. Data was analysed using the Framework method and constant comparative techniques. Sixty-six people participated in the study: people with T2DM who participated in the EXTEND programme; healthcare professionals (HCPs), EXTEND educators, EXTEND trainers, and stakeholders. Results: Our findings indicate that there is a need to develop an integrated and dedicated diabetes services in SSA healthcare systems, incorporating culturally adapted DSMES and tailored diabetes training to all professions involved in diabetes management. Traditional media and the involvement of community leaders were proposed as important elements to help engage and promote DSMES programmes in local communities. During the design and implementation of DSMES, it is important to consider individual and societal barriers to self-care. Conclusion: Findings from this study suggest that multi-faceted factors play a significant role to the implementation of DSMES programmes in LICs. In the future, EXTEND could be incorporated in the development of diabetes training and dedicated diabetes services in SSA healthcare systems, acting as an educational tool for both people with T2DM and HCPs. This project was supported by the Medical Research Council GCRF NCDs Foundation Awards 2016 Development Pathway Funding

Critical skills needs and challenges for STEM/STEAM graduates increased employability and entrepreneurship in the solar energy sector

Energy produced by photovoltaic module (PVM) is poised to deliver the UN Sustainable Development Goal 7 (SDG-7) by 2030 and Net-Zero by 2050 but not until ample graduates with adequate Solar Energy Technology (SET) skills are produced by Higher education institutions (HEIs). Although PVM has witnessed significant penetration globally, the sustainability of the growth of the sector is challenged by attendant monotonic skilled labour shortages. The evolving growth imbalance is critical in the European Union (EU), limits her global competitiveness and necessitates the need to create wider awareness on the green technology to stimulate more production of solar energy sector (SES) specific skills graduates. Discussing the mismatch between the skills Europe needs and has in the SES, the study outlines key critical skills Science, Technology, Engineering and Mathematics (STEM) cum Arts (STEAM) graduates ought to possess to secure sector employment and the challenges limiting them from acquiring the competencies. The review is conducted via extensive study of relevant literature, analysis of interviews and observations. Academic, industrial, and entrepreneurial skills are identified as critical SES needs. Designing and running educational modules/curricula that embed the identified solar technology specialist skills on students and learners are proposed as vehicle to increase their employability and entrepreneurship. This study profiles trends and developments in the SES for stakeholders’ increased awareness while presenting the specialist skills in-demand for employment in the sector. The adoption of SET Training (SETechTra) curricula/modules by the EIs will substantially increase the production of industry-ready graduates whilst decreasing the SES skills gap

Oral abstracts of the 21st International AIDS Conference 18-22 July 2016, Durban, South Africa

The rate at which HIV-1 infected individuals progress to AIDS is highly variable and impacted by T cell immunity. CD8 T cell inhibitory molecules are up-regulated in HIV-1 infection and associate with immune dysfunction. We evaluated participants (n=122) recruited to the SPARTAC randomised clinical trial to determine whether CD8 T cell exhaustion markers PD-1, Lag-3 and Tim-3 were associated with immune activation and disease progression.Expression of PD-1, Tim-3, Lag-3 and CD38 on CD8 T cells from the closest pre-therapy time-point to seroconversion was measured by flow cytometry, and correlated with surrogate markers of HIV-1 disease (HIV-1 plasma viral load (pVL) and CD4 T cell count) and the trial endpoint (time to CD4 count <350 cells/μl or initiation of antiretroviral therapy). To explore the functional significance of these markers, co-expression of Eomes, T-bet and CD39 was assessed.Expression of PD-1 on CD8 and CD38 CD8 T cells correlated with pVL and CD4 count at baseline, and predicted time to the trial endpoint. Lag-3 expression was associated with pVL but not CD4 count. For all exhaustion markers, expression of CD38 on CD8 T cells increased the strength of associations. In Cox models, progression to the trial endpoint was most marked for PD-1/CD38 co-expressing cells, with evidence for a stronger effect within 12 weeks from confirmed diagnosis of PHI. The effect of PD-1 and Lag-3 expression on CD8 T cells retained statistical significance in Cox proportional hazards models including antiretroviral therapy and CD4 count, but not pVL as co-variants.Expression of ‘exhaustion’ or ‘immune checkpoint’ markers in early HIV-1 infection is associated with clinical progression and is impacted by immune activation and the duration of infection. New markers to identify exhausted T cells and novel interventions to reverse exhaustion may inform the development of novel immunotherapeutic approaches

Performance Assessment of Fragmentation Mechanisms for Vehicular Delay-Tolerant Networks

[EN] Vehicular Delay-Tolerant Networks (VDTNs) are a new approach for vehicular communications where vehicles cooperate with each other, acting as the communication infrastructure, to provide low-cost asynchronous opportunistic communications. These communication technologies assume variable delays and bandwidth constraints characterized by a non-transmission control protocol/internet protocol architecture but interacting with it at the edge of the network. VDTNs are based on the principle of asynchronous communications, bundle-oriented communication from the DTN architecture, employing a store-carry-and-forward routing paradigm. In this sense, VDTNs should use the tight network resources optimizing each opportunistic contact among nodes. Given the limited contact times among nodes, fragmentation appears as a possible solution to improve the overall network performance, increasing the bundle delivery probability. This article proposes the use of several fragmentation approaches (proactive, source, reactive, and toilet paper) for VDTNs. They are discussed and evaluated through a laboratory testbed. Reactive and toilet paper approaches present the best results. It was also shown that only the source fragmentation approach presents worst results when compared with non-fragmentation approaches.This study was partially supported by the Instituto de Telecomunicacoes, Next Generation Networks and Applications Group (NetGNA), Portugal, by the Euro-NF Network of Excellence of the Seventh Framework Programme of EU, in the framework of the Specific Joint Research Project VDTN, and by the INESC-ID multiannual funding through the PIDDAC program funds and National Funding from the FCT - Fundacao para a Ciencia e a Tecnologia through the PEst-OE/EEI/LA0008/2011 and PTDC/EEA-TEL/099074/2008 (MPSat) Projects.Dias, JAFF.; Rodrigues, JJPC.; Isento, JN.; Pereira, PRBA.; Lloret, J. (2011). Performance Assessment of Fragmentation Mechanisms for Vehicular Delay-Tolerant Networks. EURASIP Journal on Wireless Communications and Networking. 2011(195):1-14. https://doi.org/10.1186/1687-1499-2011-195S1142011195Tatchikou R, Biswas S, Dion F: Cooperative vehicle collision avoidance using inter-vehicle packet forwarding. In Presented at the IEEE Global Telecommunications Conference (IEEE GLOBECOM 2005). St. Louis, MO, USA; 2005.Park JS, Lee U, Oh SY, Gerla M, Lun DS: Emergency related video streaming in VANET using network coding. In The Third ACM International Workshop on Vehicular Ad Hoc Networks. (VANET 2006), Los Angeles, CA, USA; 2006:102-103.Buchenscheit A, Schaub F, Kargl F, Weber M: A VANET-based emergency vehicle warning system. Presented at the First IEEE Vehicular Networking Conference (IEEE VNC 2009), Tokyo, Japan 2009.Nekovee M: Sensor networks on the road: the promises and challenges of vehicular ad hoc networks and vehicular grids. In Proceedings of the Workshop on Ubiquitous Computing and e-Research. Edinburgh, UK; 2005.Blum J, Eskandarian A, Hoffmman L: Challenges of intervehicle ad hoc networks. IEEE Trans. Intell. Transport. Syst 2004, 5(4):347-351. 10.1109/TITS.2004.838218Yousefi S, Mousavi MS, Fathy M: Vehicular ad hoc networks (VANETs): challenges and perspectives. 6th International Conference on ITS Telecommunications (ITST 2006) 2006, 761-766.Füßler H, Torrent-Moreno M, Transier M, Festag A, Hartenstein H: Thoughts on a protocol architecture for vehicular ad-hoc networks. In Presented at the 2nd International Workshop on Intelligent Transportation (WIT 2005). Hamburg, Germany; 2005.Cerf V, Burleigh S, Hooke A, Torgerson L, Durst R, Scott K, Fall K, Weiss H: Delay-tolerant networking architecture. RFC 4838 2007. [Online] [ http://www.rfc-editor.org/rfc/rfc4838.txt ]Soares VNGJ, Farahmand F, Rodrigues JJPC: A layered architecture for vehicular delay-tolerant networks. In The Fourteenth IEEE Symposium on Computers and Communications (ISCC 2009). Sousse, Tunisia; 2009:122-127.Rodrigues JJPC, Soares VNGJ, Farahmand F: Stationary relay nodes deployment on vehicular opportunistic networks. In Mobile Opportunistic Networks: Architectures, Protocols and Applications. Edited by: Denko M. CRC Press, Taylor & Francis Group (hardcover); 2011:227-243.Postel J: Internet Protocol. RFC 791 1981. [Online] [ http://www.ietf.org/rfc/rfc791.txt ]Kent CA, Moguk JC: Fragmentation considered harmful. SIGCOMM Comput Commun Rev 1995, 25(1):75-87. 10.1145/205447.205456Kim B-S, Fang Y, Wong TF, Kwon Y: Throughput enhancement through dynamic fragmentation in wireless LANs. IEEE Trans Veh Technol 2005, 54(4):1415-1425. 10.1109/TVT.2005.851361Ginzboorg P, Niemi V, Ott J: Message Fragmentation in Disruptive Networks. Nokia Research Center, Technical Report; 2009.Legner M: Map-Based Geographic Forwarding in Vehicular Networks. Department of Informatic, University of Stuttgart; 2002.Li Q, Rus D: Sending messages to mobile users in disconnected ad-hoc wireless networks. 6th Annual International Conference on Mobile Computing and Networking, New York, USA 2000, 44-55.Vahdat A, Becker B: Epidemic Routing for Partially-Connected Ad-Hoc Networks. Duke University, Technical Report; 2000.Briesemeister L, Hommel G: Overcoming fragmentation in mobile ad-hoc networks. J Commun Netw 2000, 2(3):182-187.Liu H, Sheng H, Lv Z, Li L, Ma C: A cross layer design of fragmentation and priority scheduling in vehicular ad hoc networks. 7th World Congress on Intelligent Control and Automation (WCICA 2008) 2008, 6157-6160.Joshi HP: Distributed robust geocast: a multicast protocol for inter-vehicle communication. Master Thesis, North Carolina State University; 2006.Bachir A, Benslimane A: A multicast protocol in ad hoc networks: Inter-vehicles geocast. Proceedings of the 57th IEEE Vehicular Technology Conference, Korea 2003, 2456-2460.Mikko P, Ari K, Ott J: Message fragmentation in opportunistic DTNs. In 9th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WOWMOM 2008). Newport Beach, CA, USA; 2008.Farrell S, Symington S, Weiss H: Delay-tolerant networking security overview. Internet Draft 2009. [Online] [ http://tools.ietf.org/html/draft-irtf-dtnrg-sec-overview-06 ]Magaia N, Pereira PR, Casaca A, Rodrigues J, Dias JA, Isento JN, Cervelló-Pastor C, Gallego J: Bundles fragmentation in vehicular delay-tolerant networks. 7th Euro-nf conference on next generation internet, Kaiserslautern, Germany 2011.Soares V, Rodrigues J, Farahmand F, Denko M: Exploiting node localization for performance improvement of vehicular delay-tolerant networks. In IEEE International Conference on Communications (ICC 2010). Cape Town, South Africa; 2010.Rubinstein MG, Abdesselm FB, Cavalcanti SR, Campista MEM, Alves RSA, Costa LHMK, Amorim MD, Duarte OCMB: Measuring the capacity of in-car to in-car vehicular networks. IEEE Commun Mag 2009, 47(11):128-136.Spyropoulos T, Psounis K, Raghavendra C S: Spray and wait: an efficient routing scheme for intermittently connected mobile networks. In ACM SIGCOMM 2005--Workshop on Delay Tolerant Networking and Related Networks (WDTN-05). Philadelphia, PA, USA; 2005:252-259.Lindgren A, Doria A, Davies E, Grasic S: Probabilistic routing protocol for intermittently connected networks (2010). Internet Draft 2010. [Online] [ http://tools.ietf.org/html/draft-irtf-dtnrg-prophet-06 ]Teshima S, Ohta T, Kohno E, Kakuda Y: A data transfer scheme using autonomous clustering in VANETs environment. In 10th International Symposium on Autonomous Decentralized Systems (ISADS 2011). Tokyo, Japan; 2011:477-482.Psounis K: Efficient Routing for Safety Applications in Vehicular Networks. METRANS Project DTRS98-G0019, Electrical Engineering. University of Southern California, Los Angeles, USA; 2009.Li X, Shu W, Li M, Huang H, Min-You Wu: DTN routing in vehicular sensor networks. In IEEE Global Telecommunications Conference (IEEE GLOBECOM 2008). New Orleans, USA; 2008:1-5

Development and characterization of phytosterol-enriched oil microcapsules for foodstuff application

Phytosterols are lipophilic compounds contained in plants and have several biological activities. The use of phytosterols in food fortification is hampered due to their high melting temperature, chalky taste, and low solubility in an aqueous system. Also, phytosterols are easily oxidized and are poorly absorbed by the human body. Formulation engineering coupled with microencapsulation could be used to overcome these problems. The aim of this study was to investigate the feasibility of encapsulating soybean oil enriched with phytosterols by spray-drying using ternary mixtures of health-promoting ingredients, whey protein isolate (WPI), inulin, and chitosan as carrier agents. The effect of different formulations and spray-drying conditions on the microencapsules properties, encapsulation efficiency, surface oil content, and oxidation stability were studied. It was found that spherical WPI-inulin-chitosan phytosterol-enriched soybean oil microcapsules with an average size below 50 μm could be produced with good encapsulation efficiency (85%), acceptable level of surface oil (11%), and water activity (0.2–0.4) that meet industrial requirements. However, the microcapsules showed very low oxidation stability with peroxide values reaching 101.7 meq O2/kg of oil just after production, and further investigations and optimization are required before any industrial application of this encapsulated system

Single nucleotide polymorphism (SNP) diversity of cassava genotypes in relation to cassava brown streak disease in Mozambique

Published online: 14 Jun 2018Cassava brown streak disease (CBSD) remains a major threat to cassava production in Mozambique. Breeding for CBSD resistant varieties that are also preferred by farmers is an integral part of managing the disease. The main objective of the study was to determine the genetic relationship between farmer-preferred varieties from Mozambique with those from Tanzania whose resistance to CBSD is known and some of which are being used as parents in quantitative trait loci (QTL) detection studies. To achieve this, 103 genotypes collected from farmers’ field in three provinces of Mozambique were genotyped together with five varieties from Tanzania whose CBSD response is well known. Thirty-five single nucleotide polymorphism (SNP) markers with a high minor allele frequency in East African landraces were used. Results indicated that seven Mozambican genotypes were genetically similar to either one of the four Tanzanian CBSD resistant genotypes while Xino Nn'gole was genetically identical to Namikonga a CBSD resistant variety, based on the SNPs used here. Little genetic differentiation was observed in cassava between provinces, with the majority of genetic variation distributed within individual genotypes (98%) rather than among provinces (2%). Both observed (Ho) and expected (He) heterozygosity in three provinces were generally high (Ho = 0.496) and (He = 0.455). There is a high likelihood that the eight genotypes similar/identical to those from Tanzania may share the same QTL associated with CBSD resistance thus should be further evaluated for agronomic traits as well as response to CBSD

Temporal Variability of Solar Energy Availability in the Conditions of the Southern Region of Mozambique

The use of photovoltaic solar energy is affected by variations in the availability of solar radiation, which creates stability in solar panels. In our case, the need arose to study the temporal variability of solar energy in the southern region of Mozambique. This was followed by a descriptive sequence, applying the analytical method for the classification of days and the analysis of the day’s variability of clear, cloudy and intermediate skies in the data from three regional stations. The results show that it was mostly on clear sky days (44.64%), enhancing the use of solar energy. Statistical analysis of the frequency density variability shows that days with intermediate skies have a similar behavior, however they present a smooth decrease, because for variation of clear sky index ∆Kt* in the interval [-2,2] it is higher. The values of Kt* vary between 0.3342–1.2764, the minimum is observed in the month of July and the maximum in December and the variations during the daily course of the Kt* determined according to its standard deviation show such suitability to the model adopted for the calculation of global irradiation under the clear sky, as an appropriate choice of time interval and amplitude for the study of variations.</jats:p