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Recent biotechnical advances in the in vitro culture of cholangiocytes and generation of bioengineered biliary tissue have a high potential for creating biliary tissue to be used for disease modeling, drug screening, and transplantation. For the past few decades, scientists have searched for a source of cholangiocytes, focused on primary cholangiocytes or cholangiocytes derived from hepatocytes or stem cells. At the same time, the development of scaffolds for biliary tissue engineering for transplantation and modeling of cholangiopathies has been explored. In this review, we provide an overview on the current understanding of cholangiocytes sources, the effect of signaling molecules, and transcription factors on cell differentiation, along with the effects of extracellular matrix molecules and scaffolds on bioengineered biliary tissues, and their application in disease modeling and drug screening. Impact statement Over the past few decades, biliary tissue engineering has acquired significant attention, but currently a number of factors hinder this field to eventually generate bioengineered bile ducts that mimic in vivo physiology and are suitable for transplantation. In this review, we present the latest advances with respect to cell source selection, influence of growth factors and scaffolds, and functional characterization, as well as applications in cholangiopathy modeling and drug screening. This review is suited for a broad spectrum of readers, including fundamental liver researchers and clinicians with interest in the current state and application of bile duct engineering and disease modeling.

Since HIV was first identified, and in a relatively short period of time, AIDS has become one of the most devastating infectious diseases of the 21st century. Classical antiretroviral therapies were a major step forward in disease treatment options, significantly improving the survival rates of HIV-infected individuals. Even though these therapies have greatly improved HIV clinical outcomes, antiretrovirals (ARV) feature biopharmaceutic and pharmacokinetic problems such as poor aqueous solubility, short half-life, and poor penetration into HIV reservoir sites, which contribute to the suboptimal efficacy of these regimens. To overcome some of these issues, novel nanotechnology-based strategies for ARV delivery towards HIV viral reservoirs have been proposed. The current review is focused on the benefits of using lipid-based nanocarriers for tuning the physicochemical properties of ARV to overcome biological barriers upon administration. Furthermore, a correlation between these properties and the potential therapeutic outcomes has been established. Biotechnological advancements using lipid nanocarriers for RNA interference (RNAi) delivery for the treatment of HIV infections were also discussed., This research was funded by FCT/MCTES—Foundation for Science and Technology I.P. from the Minister of Science, Technology, and Higher Education (PIDDAC) and European Regional Development Fund (ERDF) by the COMPETE—Programa Operacional Factores de Competitividade (POFC) through the project CONCERT [POCI-01-0145-FEDER-032651 and PTDC/NANMAT/326512017] and the Strategic Funding UID/FIS/04650/2019 and “Contrato-Programa” UIDB/ 04469/2020 (CF-UM-UP and CBMA). Marlene Lúcio thanks FCT and ERDF for the doctoral position [CTTI-150/18-CF (1)] in the scope of the project CONCERT. Maria João Faria thanks FCT for PhD grant [2020.06561.BD].

Population growth and climate change lead agricultural cultures to face environmental degradation and rising of resistant diseases and pests. These conditions result in reduced product quality and increasing risk of harmful toxicity to human health. Thus, the prediction of the occurrence of diseases and pests and the consequent avoidance of the erroneous use of phytosanitary products will contribute to improving food quality and safety and environmental land protection. This study presents the design and construction of a low-cost IoT sensor mesh that enables the remote measurement of parameters of large-scale orchards. The developed remote monitoring system transmits all monitored data to a central node via LoRaWAN technology. To make the system nodes fully autonomous, the individual nodes were designed to be solar-powered and to require low energy consumption. To improve the user experience, a web interface and a mobile application were developed, which allow the monitored information to be viewed in real-time. Several experimental tests were performed in an olive orchard under different environmental conditions. The results indicate an adequate precision and reliability of the system and show that the system is fully adequate to be placed in remote orchards located at a considerable distance from networks, being able to provide real-time parameters monitoring of both tree and the surrounding environment.

Electric Vehicles (EV) have gained interest over the past decade. Because of this, to support EV technology installation of charging stations are required. Charging EVs from renewable energy provides a sustainable means of transport. E-bikes can help mitigate some mobility problems, particularly in large cities and metropolitan areas. This paper shows the development and implementation of a solar e-bike charging station with photovoltaic production, with energy storage system. The implemented system has a centralized control and allow an efficient management of the various resources and contemplates the possibility of four simultaneous e- bikes where user identification is performed by RFID. Finally, it is provided a user interface through an HMI panel and a web page where it will be possible to access the DataLog to consult the user activity and all charging parameters. Keywords: Renewable energy, Solar charging station, Programmable logic controller

Weak governance institutions are one of the leading causes of resource challenge in the Gulf of Guinea. The literature has overwhelmingly focused on incremental adjustments in institutions and resource management practices as possible solutions. This article calls for a transformative approach. It uses data from case studies from four Gulf of Guinea countries to present a framework for creating transformative change through resource governance. The particular focus of this article is the co-design phase. It discusses a participatory and rapid co-design approach which was used to explore pathways for achieving transformative resource governance. One of its conclusions is that transformative resource governance is a process, rather than an end, and emerges from productive engagement between governments and local communities.

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Cascaded multilevel inverters offer several advantages over other multilevel structures: modularity, high voltage capability, reliability. Additionally, a large number of cascaded inverters using a square wave modulation method allow low losses in the inverter and low harmonic distortion in the output voltage. This paper analyzes the main features of one of these modulation methods especially in what concerns to real- time implementation in a FPGA, output voltage distortion in single- and three-phase systems and modulation range in static and dynamic conditions. Also, scalability is addressed in order to evaluate the method's capability to be used in high voltage applications. Simulation results with a different number of H- bridge inverters are presented and they allow obtaining the main conclusions; experimental results verify and support those conclusions.

We present an analysis of existing methods to automatic classification of photos according to aesthetics. We review different components of the classification process: existing evaluation datasets, their properties, most commonly-used image features, qualitative and quantitative, and classification results where comparable. We argue there are methodology gaps in the existing approaches to evaluating the classification results. We introduce the results of our experiments with Random Forest classification applied to image aesthetics classification and compare them to AdaBoost and SVM approaches.

Computer Assisted Therapy is an applied and research field that has been rapidly evolving hand in hand with the advances of technology. In particular, the mass adoption of the internet and computers as tools to support several types of approaches has shown good results for a wide assortment of issues [1]. These technologies, primarily used to support therapists and clinicians while managing their records, accessing local or remote information [1][2], have more recently, and most importantly, been growingly used to serve patients as well, either independently or as a support for cooperation between patient and therapists. Amongst the existing examples, one can find simple registration (e.g., amount of cigarettes per day) diaries, short text-based tests or basic procedures and guidelines [3] or more advanced systems offering some support for personalization within the used tools [4] and data exchange between actors.

Software for young children requires specific attention to a variety of details that range from the used metaphors, interaction modalities and even used language. These aspects gain further relevance when creating software for critical activities such as fear therapy, requiring specific approaches during the design process right from the start. This paper describes the design process of a set of software solutions for young children's fear therapy using mobile devices. We address the used techniques, procedures and describe the resulting prototypes. Initial evaluation results and future work plans are also presented.

Model-driven development (MDD) conceptions and techniques essentially centre the focus of development on models. They are subject of current research as they allow enhanced productivity, technological platform independence and longevity of software artifacts. Another area of current research is the ubiquitous/pervasive computing area. This field of computing research focuses on the widespread adoption of embedded or mobile heterogeneous computing devices, which, when properly orchestrated, globally compose pervasive information systems (PIS). This work intends to clarify how should be MDD concepts and techniques structurally consolidated into an approach to software development for PIS. It involves two projects as case studies. From these case studies, it will be proposed methodological insights to design approaches for software development of PIS. While clarifying several issues pertaining to MDD for PIS, it shall promote other research works based on issues needing further study.

Agents must decide, i.e., choose a preferred option from among a large set of alternatives, according to the precise context where they are immersed. Such a capability defines to what extent they are autonomous. But, there is no one way of deciding, and the classical mode of taking utility functions as the sole support is not adequate for situations constrained by qualitative features (such as wine selection, or putting together a football team). The BVG agent architecture relies on the use of values (multiple dimensions against which to evaluate a situation) to perform choice among a set of candidate goals. In this paper, we propose that values can also be used to guide the adoption of new goals from other agents. We argue that agents should base their rationalities on choice rather than search.

Women are particularly vulnerable to sexual HIV-1 transmission. Oral pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) is highly effective in avoiding new infections in men, but protection has only been shown to be moderate in women. Such differences have been associated, at least partially, to poor drug penetration of the lower female genital tract and the need for strict adherence to continuous daily oral intake of TDF/FTC. On-demand topical microbicide products could help circumvent these limitations. We developed electrospun fibers based on polycaprolactone (PCL fibers) or liposomes associated to poly(vinyl alcohol) (liposomes-in-PVA fibers) for the vaginal co-delivery of TDF and FTC, and assessed their pharmacokinetics in mice. PCL fibers and liposomes-in-PVA fibers were tested for morphological and physico chemical properties using scanning electron microscopy, differential scanning calorimetry and X-ray diffrac tometry. Fibers featured organoleptic and mechanical properties compatible with their suitable handling and vaginal administration. Fluorescent quenching of mucin in vitro – used as a proxy for mucoadhesion – was intense for PCL fibers, but mild for liposomes-in-PVA fibers. Both fibers were shown safe in vitro and able to rapidly release drug content (15–30 min) under sink conditions. Liposomes-in-PVA fibers allowed increasing genital drug concentrations after a single intravaginal administration when compared to continuous daily treatment for five days with 25-times higher oral doses. For instance, the levels of tenofovir and FTC in vaginal lavage were around 4- and 29-fold higher, respectively. PCL fibers were also superior to oral treatment, although to a minor extent (approximately 2-fold higher drug concentrations in lavage). Vaginal tissue drug levels were generally low for all treatments, while systemic drug exposure was negligible in the case of fibers. These data suggest that proposed fibers may provide an interesting alternative or an ancillary option to oral PrEP in women., This work was financed by Programa Gilead GÉNESE (refs. PGG/ 046/2015) and Portuguese funds through FCT - Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior in the framework of the project “Institute for Research and Innovation in Health Sciences” UID/BIM/04293/2019. The work was also financed by FCT in the framework of the Strategic Funding UID/FIS/04650/2019 and in the ambit of the project POCI-01-0145-FEDER-032651 and PTDC/NAN-MAT/326512017, co-financed by the FEDER, through COMPETE 2020, under PORTUGAL 2020, and FCT. Marlene Lúcio thanks FCT and ERDF for doctoral position Ref. CTTI-150/18-CF(1) in the ambit of the project CONCERT (POCI-01-0145-FEDER-032651 and PTDC/NAN-MAT/326512017).