Self-sufficient Manner Research Articles

A Novel Sustainable and Self-Sufficient Biotechnological Strategy for Directly Transforming Sewage Sludge into High-Value Liquid Biochemicals.

Sewage sludge, as a carbon-rich byproduct of wastewater treatment, holds significant untapped potential as a renewable resource. Upcycling this troublesome waste stream represents great promise in addressing global escalating energy demands through its wide practice of biochemical recovery concurrently. Here, we propose a biotechnological concept to gain value-added liquid bioproducts from sewage sludge in a self-sufficient manner by directly transforming sludge into medium-chain fatty acids (MCFAs). Our findings suggest that yeast, a cheap and readily available commercial powder, would involve ethanol-type fermentation in chain elongation to achieve abundant MCFA production from sewage sludge using electron donors (i.e., ethanol) and acceptors (i.e., short-chain fatty acids) produced in situ. The enhanced abundance and transcriptional activity of genes related to key enzymes, such as butyryl-CoA dehydrogenase and alcohol dehydrogenase, affirm the robust capacity for the self-sustained production of MCFAs. This is indicative of an effective metabolic network established between yeast and anaerobic microorganisms within this innovative sludge fermentation framework. Furthermore, life cycle assessment and techno-economic analysis evidence the sustainability and economic competitiveness of this biotechnological strategy. Overall, this work provides insights into sewage sludge upgrading independent of additional carbon input, which can be applied in existing anaerobic sludge fermentation infrastructure as well as to develop new applications in a diverse range of industries.

Benchmarking AutoML-Supported Lead Time Prediction

In manufacturing companies, especially in small and medium enterprises (SME) in the make-to-order domain, predicting accurate lead times for highly customisable products poses a challenge. One avenue to tackle this challenge is using machine learning to create data-driven models. With the advent of Automated Machine Learning (AutoML), there is a potential also for non-data-scientists in the SMEs to utilise machine learning in a self-sufficient manner. In this paper, we benchmarked three AutoML solutions on data from two SMEs and compared their models with manual predictions currently in productive use as well as simple mean models. We furthermore investigated how these solutions support the model development process. While we found that the models generated by the AutoML solutions outperformed manual predictions, labour-intensive parts of the model development process such as data understanding and pre-processing as well as feature engineering were not supported sufficiently by the benchmarked solutions.

Improved l-phenylglycine synthesis by introducing an engineered cofactor self-sufficient system

l-phenylglycine (L-phg) is a valuable non-proteinogenic amino acid used as a precursor to β-lactam antibiotics, antitumor agent taxol and many other pharmaceuticals. L-phg synthesis through microbial bioconversion allows for high enantioselectivity and sustainable production, which will be of great commercial and environmental value compared with organic synthesis methods. In this work, an L-phg synthesis pathway was built in Escherichia coli resulting in 0.23 mM L-phg production from 10 mM l-phenylalanine. Then, new hydroxymandelate synthases and hydroxymandelate oxidases were applied in the L-phg synthesis leading to a 5-fold increase in L-phg production. To address 2-oxoglutarate, NH4+, and NADH shortage, a cofactor self-sufficient system was introduced, which converted by-product l-glutamate and NAD+ to these three cofactors simultaneously. In this way, L-phg increased 2.5-fold to 2.82 mM. Additionally, in order to reduce the loss of these three cofactors, a protein scaffold between synthesis pathway and cofactor regeneration modular was built, which further improved the L-phg production to 3.72 mM with a yield of 0.34 g/g L-phe. This work illustrated a strategy applying for whole-cell biocatalyst converting amino acid to its value-added chiral amine in a cofactor self-sufficient manner.

Distributed Sensing with Low-Cost Mobile Sensors Toward a Sustainable IoT

Cities are monitored by sparsely positioned high-cost reference stations that fail to capture local variations. Although these stations must be ubiquitous to achieve high spatio-temporal resolutions, the required capital expenditure makes that infeasible. Here, low-cost IoT devices come into prominence; however, non-disposable and often non-rechargeable batteries they have pose a huge risk for the environment. The projected numbers of required IoT devices will also yield to heavy network traffic, thereby crippling the RF spectrum. To tackle these problems and ensure a more sustainable IoT, cities must be monitored with fewer devices extracting highly granular data in a self-sufficient manner. Hence, this paper introduces a network architecture with energy harvesting low-cost mobile sensors mounted on bikes and unmanned aerial vehicles, underpinned by key enabling technologies. Based on the experience gained through real-world trials, a detailed overview of the technical challenges encountered when using low-cost sensors and the requirements for achieving high spatio-temporal resolutions in the 3D space are highlighted. Finally, to show the capability of the envisioned architecture in distributed sensing, a case study on air quality monitoring investigating the variations in particulate and gaseous pollutant dispersion during the first lockdown of the COVID.19 pandemic is presented. The results showed that using mobile sensors is as accurate as using stationary ones with the potential of reducing device numbers, leading to a more sustainable IoT.

Space Microgrids for Future Manned Lunar Bases: A Review

Several space organizations have been planning to establish a permanent, manned base on the Moon in recent years. Such an installation demands a highly reliable electrical power system (EPS) to supply life support systems and scientific equipment and operate autonomously in a fully self-sufficient manner. This paper explores various technologies available for power generation, storage, and distribution for space microgrids on the Moon. Several factors affecting the cost and mass of the space missions are introduced and analysed to provide a comprehensive comparison among the available solutions. Besides, given the effect of base location on the design of a lunar electrical power system and the mission cost, various lunar sites are introduced and discussed. Finally, the control system requirements for the reliable and autonomous operation of space microgrids on the Moon are presented. The study is complemented by discussing promising future technological solutions that could be applied upon a lunar microgrid.

Towards Dynamic Vertical Urbanism

Nowadays a great number of new developments are claimed in the name of “vertical city”, yet few represent this important characteristic. This paper aims to propose a novel vertical city framework, or in other words, dynamic vertical urbanism, featuring constant vertical urban transformation by applying the state-of-the-art construction technologies. First, successful and unsuccessful precedents of building complexes which inspire this novel concept will be analyzed. In addition, building technologies that are crucial for the implementation of this framework will be introduced. As a result, this vertical city concept has the ability to integrate five basic elements of a city: vertical and horizontal circulation systems as its paths, a flexible building envelope as its edges, variable mix-used functional blocks as its districts, sky bridges and roof gardens as its nodes, and the complex itself as a landmark. More importantly, it can change its size, form and function with the help of construction automation technologies, open building principles, and process information modeling. it can also responsively evolve in accordance with social, economic, and environmental shifts in a self-sufficient manner, meanwhile avoiding the risk of being homogeneous with surrounding buildings. Finally, the complex will perform as a series of interconnected components which act together to form a living organism that provides various functions such as corporate, residential, commercial, academic, medical, legal, and infrastructural. In conclusion, this paper will provide researchers, architects and urban designers with a valuable example for the future vertical city developments and beyond.

An Interdisciplinary Approach to the Sustainability of a Gravity-Fed Water System in the Peruvian Andes

This paper analyzes the methods utilized by the Princeton University Chapter of Engineers Without Borders to ensure the sustainability of a gravity-fed water system in rural northwestern Peru. While similar small scale development projects consider sustainability in their design process, some do not recognize the importance of an interdisciplinary approach to sustainability. This team, however, is inherently interdisciplinary in nature due to its unique subteam structure, which subsequently affects its approach to sustainability. By examining the technical, social, and financial considerations of the project conducted by the Princeton University Chapter of Engineers Without Borders, this paper argues for a three-pronged approach to sustainability. As can be seen through thoughtful design parameters, strong local partnerships, and strategic financial mechanisms, the project displays promise of future success with regards to sustainability. The main objective of the Princeton Chapter of Engineers Without Borders in this partnership is to ensure that the community has the knowledge, tools, and resources necessary to maintain the water system in a self-sufficient manner at the completion of the chapter’s involvement.

Utilization of a Mobile Dental Vehicle for Oral Healthcare in Rural Areas.

Oral diseases remain one of the major global public health challenges, and the worldwide urban–rural disparities in oral health are significant. Residents in rural areas generally suffer from a higher prevalence and severity of dental caries and periodontal disease, yet they face numerous difficulties and barriers in accessing oral healthcare. Conventional strategies, such as building of dental clinics or, hospitals, or the provision of outreach services by using disposable materials, are neither practical nor effective in rural settings. Mobile dental vehicles (MDVs) have been proposed as an alternative strategy to supplement the traditional oral healthcare in many regions. They have usually been utilized in school-based oral health programs, providing dental care to the homeless or migrants, and screening programs for the population for various oral diseases. Due to their high mobility, MDVs are particularly valuable for the underserved populations living in rural areas. The advance of dental devices enables MDVs to be operated in a self-sufficient manner. This allows the MDV to function almost as well as a conventional dental clinic, providing a variety of dental treatments, including scaling, restoration, and oral surgery. This article discusses the use of MDVs as a solution to urban–rural inequality in receiving oral healthcare.

Basic Seismic Response Capability of Hospitals in Lima, Peru.

The objective of the study was to research the basic seismic response capability (BSRC) of hospitals in Lima Metropolitana. A large number of wounded could be registered in case of an earthquake; therefore, operational hospitals are necessary to cure the injured. The study focused on the operational performance of the hospitals, autonomies of essential resources such as power, water, medical gases, and medicine, in addition to the availability of emergency communication system and ambulances. Data by a probabilistic seismic risk analysis have been used to assess the operational level of the hospitals. Subsequently, availability of an essential resource has been combined with the immediately operational hospitals to evaluate the BSRC of the health facilities. Forty-one of Lima's hospitals have been analyzed for a seismic event with 72-100 years of a return period. Three hospitals (7.3%) were capable to work in a self-sufficient manner for 72 hours, another three (7.3%) for 24 hours, and one (2.4%) for 12 hours. Results showed a low performance of the hospitals in case of an earthquake. The issue is due to the high seismic vulnerability of the existing structures. Given the importance of Lima city in Peru, structural and nonstructural retrofitting plans should be implemented to improve the preparedness of the health system in case of an emergency. (Disaster Med Public Health Preparedness. 2019;13:138-143).

Power Flow Control in Multi-Terminal HVDC Grids Using a Serial-Parallel DC Power Flow Controller

Multi-terminal HVDC (MT-HVDC) grids have no capability of power flow control in a self-sufficient manner. To address this important issue, utilization of dc–dc high power and high-voltage converters is motivated. However, proposing suitable partial-rated dc–dc converters as well as their suitable modeling and control in both primary and secondary control layers as well as the stability analysis are the existing challenges that should be alleviated beforehand. This paper addresses the control of power flow problem through the application of a power converter with a different connection configuration, namely, serial parallel dc power flow controller (SPDC-PFC). The SPDC-PFC input is the transmission line voltage, and its output is transmission line current. Therefore, employing a full-power dc–dc converter is avoided as a merit. Additionally, in this paper, the common two-layer MT-HVDC grid control framework comprised of primary and secondary layers is efficiently modified in order to integrate the SPDC-PFC. A differential direct voltage versus active power droop control scheme is applied to the SPDC-PFC at the local control layer, guaranteeing dynamic stability, while an extended dc power-flow routine—integrating the SPDC-PFC—is developed at the secondary control layer to ensure the static stability of the entire MT-HVDC grid. The proposed control framework enables the SPDC-PFC to regulate the flow of current/power in the envisioned HVDC transmission line. From the static and dynamic simulation results conducted on the test CIGRE B4 MT-HVDC grid, successful operation of the proposed SPDC-PFC and control solutions are demonstrated by considering power flow control action. In more detail, the SPDC-PFC successfully regulates the compensated lines’ power to the desired reference both in static and dynamic simulations by introducing suitable compensation voltages. In addition, good dynamic performance under both SPDC-PFC power reference and wind power-infeed change is observed.

A novel approach of vertical city in southern china utilizing construction robotics, open building principles, modular construction and prefabrication

A number of new developments are claimed in the name of “vertical city”, yet few represents an important characteristic of a city, which is the ability to constantly transform. Based on the analysis of several successful and unsuccessful precedents of building complexes, this paper aims to propose a novel approach of vertical city featuring constant vertical urban transformation by applying the state-of-the-art construction technologies. Meanwhile, this vertical city approach has the ability to integrate five basic elements of a city: vertical and horizontal circulation systems as its paths, a flexible building envelope as its edges, variable mix-used functional blocks as its districts, sky bridges and roof gardens as its nodes, and the complex itself as a landmark. More importantly, it can change its size, form and function with the help of construction automation technologies and open building principles, and responsively evolve in accordance with social, economic, and environmental shifts in a self-sufficient manner, meanwhile avoiding the risk of being homogeneous with surrounding buildings. Eventually, the complex will perform as a series of interconnected components which act together to form a living organism that performs various functions and purposes such as office, residential, commercial, school, hospital, police station, and infrastructure

Self-Sufficient Formaldehyde-to-Methanol Conversion by Organometallic Formaldehyde Dismutase Mimic.

The catalytic networks of methylotrophic organisms, featuring redox enzymes for the activation of one-carbon moieties, can serve as great inspiration in the development of novel homogeneously catalyzed pathways for the interconversion of C1 molecules at ambient conditions. An imidazolium-tagged arene-ruthenium complex was identified as an effective functional mimic of the bacterial formaldehyde dismutase, which provides a new and highly selective route for the conversion of formaldehyde to methanol in absence of any external reducing agents. Moreover, secondary amines are reductively methylated by the organometallic dismutase mimic in a redox self-sufficient manner with formaldehyde acting both as carbon source and reducing agent.

A combined system of microbial fuel cell and intermittently aerated biological filter for energy self-sufficient wastewater treatment.

Energy self-sufficiency is a highly desirable goal of sustainable wastewater treatment. Herein, a combined system of a microbial fuel cell and an intermittently aerated biological filter (MFC-IABF) was designed and operated in an energy self-sufficient manner. The system was fed with synthetic wastewater (COD = 1000 mg L−1) in continuous mode for more than 3 months at room temperature (~25 °C). Voltage output was increased to 5 ± 0.4 V using a capacitor-based circuit. The MFC produced electricity to power the pumping and aeration systems in IABF, concomitantly removing COD. The IABF operating under an intermittent aeration mode (aeration rate 1000 ± 80 mL h−1) removed the residual nutrients and improved the water quality at HRT = 7.2 h. This two-stage combined system obtained 93.9% SCOD removal and 91.7% TCOD removal (effluent SCOD = 61 mg L−1, TCOD = 82.8 mg L−1). Energy analysis indicated that the MFC unit produced sufficient energy (0.27 kWh m−3) to support the pumping system (0.014 kWh m−3) and aeration system (0.22 kWh m−3). These results demonstrated that the combined MFC-IABF system could be operated in an energy self-sufficient manner, resulting to high-quality effluent.

A 90-liter stackable baffled microbial fuel cell for brewery wastewater treatment based on energy self-sufficient mode

A 90-liter stackable pilot microbial fuel cell was designed and proved to be capable for brewery wastewater treatment and simultaneous electricity harvested. The system was stacked by 5 easily-stackable modules, and operated in an energy self-sufficient manner for more than 6months. Tests were conducted under two different influent strengths (diluted wastewater, stage 1; raw wastewater, stage 2). The COD, SS removal efficiencies were 84.7% and 81.7% at stage 1, 87.6% and 86.3% at stage 2. The system produced enough energy (0.056kWh/m3 at stage 1, 0.097kWh/m3 at stage 2) to power the pumping system (0.027kWh/m3 at both stages), net electrical energy of 0.021kWh/m3 and 0.034kWh/m3 were harvested. These results show that this pilot-scale system could be used to effectively treat real wastewater with zero energy input.

A big data platform to enable integration of high quality clinical data and next generation sequencing data

Today, personalized medicine is closer to reality than ever before through targeted treatment, however, the substantial increase in data correspondingly requires scalable systems to continue to effectively manage the data and to remain current with advancing technology. As organizations move to advance translational research to achieve personalized medicine, researchers and clinicians must manage informatics, however, there is a shortage of fully integrated informatics solutions that integrate, store, and analyze clinical and omics data from diverse sources – generated in-house as well as public consortiums. Many researchers and clinicians must rely on bioinformaticians to perform mundane data management tasks in order to validate a simple hypothesis. Oracle Health Sciences Translational Research Center provides a complete and scalable informatics solution, with centralized data storage and analysis across genetic information areas (genomics, transcriptomics, and proteomics), vendor platforms, biological data types, and clinical data sources. Organizations such as Cancer Research UK, Erasmus MC, MD Anderson Cancer Center and UPMC have adopted this solution and are evaluating treatment responses for similar patients in a self-sufficient manner, ultimately shortening the biomarker development cycle and accelerating the adoption of personalized medicine.

Empowering women at home and beyond: applying Japanese experiences for poverty alleviation

The problem of poverty pockets in middle income countries has been identified as a major constraint for realising the Millennium Development Goals. There is an international need to develop programmes that alleviate poverty of identified populations without incurring their dependency on external aid. Aiming at developing such a programme, this article introduces the Japanese post-war Life Improvement Program and analyses the potential of its application to contemporary developing countries for poverty alleviation in a self-sufficient manner, intending to empower women. Issues such as gender relations, evaluating impacts, and linking practices to larger programmes and policies are also discussed.

Prosthetic networks – synthetic biology-inspired treatment strategies for metabolic disorders

Since Paracelsus’ (1493-1541) definition that the dosing makes the drug the basic treatment strategies have largely remained unchanged. We continue to use a precise prescribed dose of a small-molecule drug, a protein therapeutic or a therapeutic transgene to constitutively modulate or complement the activity of a disease-relevant target. However, this treatment concept does neither consider the metabolic dynamics nor the interdependence of the most important pathophysiologies of the 21st century such as obesity, diabetes and cardiovascular disorders. Synthetic biology-inspired prosthetic networks may act as metabolic prostheses that provide the dynamic interventions, the immediate pre-disease action and the multi-target capacity required to meet with the treatment challenges of the future. Prosthetic networks consist of synthetic sensoreffector gene circuits that (i) seamlessly operate in implanted designer cells, (ii) constantly sense, monitor and score metabolic disturbances in peripheral circulation, (iii) process OFF-level concentrations of pathologic metabolites, and (iv) coordinate an adjusted therapeutic response in an (v) automatic and self-sufficient manner. We will present our latest generation of synthetic mammalian gene circuits and provide a few examples of prosthetic networks operating in animal models of prominent human diseases to highlight the challenges and impact of synthetic biology on future biomedical applications.

Short-Term Operation Scheduling in Renewable-Powered Microgrids: A Duality-Based Approach

This paper considers the operation scheduling problem in renewable-powered microgrids, which is used to determine the least-cost unit commitment (UC) and the associated dispatch, while meeting load, environmental, and system operating requirements. The intermittency nature of the renewable energy sources, as well as microgrid's capacity to operate either in parallel with, or autonomously of, the traditional power grid, pose new challenges to this classic optimization task. A probability-based concept, probability of self-sufficiency (PSS), is introduced to indicate the probability that the microgrid is capable of meeting local demand in a self-sufficient manner. Furthermore, to the best of our knowledge, we make the first attempt in approaching the mixed-integer UC problem from a convex optimization perspective, which leads to an analytical closed-form characterization of the optimal commitment and dispatch solutions. The simulation results show that 1) the proposed method achieves an efficient performance that incurs no loss of optimality with lower complexity than existing algorithms; 2) an energy storage system (ESS) with suitable capacity contributes to the self-sufficiency target of a microgrid, and the stored energy varies less remarkably as the microgrid tends to operate more independently; 3) the proposed method provides guidelines in deciding the ESS size to achieve a desired PSS.

Molecular dynamics simulations reveal structural coordination of Ffh‐FtsY heterodimer toward GTPase activation

Two homologous GTPases (guanine-triphosphatases) in the signal recognition particle (SRP) and its receptor (SR) use their cumulative energy during GTP (guanine-triphosphate) hydrolysis to control the co-translational protein targeting process. Distinct from classical GTPases, which rely on external factors to hydrolyze GTP, SRP GTPases stimulate one another's activity in a self-sufficient manner upon SRP-SR complex association. Although both ground-state and putative transition-state GTP analogs have been used to recapitulate the state of GTPase activation, the underlying mechanism of the activated state still remains elusive. In particular, several residues that were placed in pending positions have been shown to be important to GTP hydrolysis in biochemical studies. Here, we examined the stability and dynamics of three interaction networks involving these residues and discovered that they contribute to the GTPase activation via well-tuned conformational changes. The crystallographically identified pending residues Ffh:R191/FtsY:R195 undergo extensive conformational rearrangements to form persisted interactions with FtsY:E284/Ffh:E274, explaining the biochemically observed defective effect of R191 mutant to the activation of both GTPases. In addition, the side chain of FtsY:R142, one of the most important catalytic residues, rotates to an extended conformation that could more efficiently maintain the electrostatic balance for GTP hydrolysis. Finally, the invariant residues Ffh:G190 and FtsY:G194, instead of the supposed auxiliary water molecules, are proposed to stabilize the nucleophilic waters during GTPase activation. In complementary to experimental observations, these findings suggest a more favorable interaction model for SRP GTPase activation and would thus benefit to our understanding of how SRP GTPases regulate the protein targeting pathway.

Molecular diversity—the toolbox for synthetic gene switches and networks

The rapid development of synthetic biology is a paradigm of how the molecular diversity of naturally occurring gene control components can be used to design synthetic control devices and gene networks that provide precisely programmed transgene expression dynamics in space and time. Here we offer an overview on recent advances in the modular design of trigger-inducible mammalian expression devices that are either responsive by exogenous stimuli such as chemicals and physical cues or controlled by endogenous metabolites driving prosthetic circuits to treat metabolic disorders in a self-sufficient manner. Compatible genetic switches can also be assembled to synthetic gene networks that show highly complex expression dynamics such as temporally resolved band-detect functions or oscillating transgene expression profiles. The ongoing metagenomic discovery and characterization of the unexplored sequence space is constantly increasing the molecular diversity in fundamental control components that fuels the further development of synthetic biology.