Showing papers by "University of Southern Denmark published in 2022"

Photocatalytic TiO2 nanomaterials as potential antimicrobial and antiviral agents: Scope against blocking the SARS-COV-2 spread

Abstract: The whole world is struggling with current coronavirus pandemic that shows urgent need to develop novel technologies, medical innovations or innovative materials for controlling SARS-CoV-2 infection. The mode of infection of SARS-CoV-2 is still not well known and seems to spread through surface, air, and water. Therefore, the whole surrounding environment needs to be disinfected with continuous function. For that purpose, materials with excellent antiviral properties, cost effective, environmental friendly and practically applicable should be researched. Titanium dioxide (TiO2) under ultraviolet light produces strong oxidative effect and is utilized as photocatalytic disinfectant in biomedical field. TiO2 based photocatalysts are effective antimicrobial/antiviral agents under ambient conditions with potential to be used even in indoor environment for inactivation of bacteria/viruses. Interestingly, recent studies highlight the effective disinfection of SARS-CoV-2 using TiO2 photocatalysts. Here, scope of TiO2 photocatalysts as emerging disinfectant against SARS-CoV-2 infection has been discussed in view of their excellent antibacterial and antiviral activities against various bacteria and viruses (e.g. H1N1, MNV, HSV, NDV, HCoV etc.). The current state of development of TiO2 based nano-photocatalysts as disinfectant shows their potential to combat with SARS-CoV-2 viral infection and are promising for any other such variants or viruses, bacteria in future studies.

The molecular characteristics of high-grade gastroenteropancreatic neuroendocrine neoplasms.

Abstract: High-grade (HG) gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) are rare but have a very poor prognosis and represent a severely understudied class of tumours. Molecular data for HG GEP-NEN are limited, and treatment strategies for the carcinoma subgroup (HG GEP-NEC) are extrapolated from small-cell lung cancer (SCLC). After pathological re-evaluation, we analysed DNA from tumours and matched blood samples from 181 HG GEP-NEN patients; 152 neuroendocrine carcinomas (NEC) and 29 neuroendocrine tumours (NET G3). Based on the sequencing of 360 cancer-related genes, we assessed mutations and copy number alterations (CNA). For NEC, frequently mutated genes were TP53 (64%), APC (28%), KRAS (22%) and BRAF (20%). RB1 was only mutated in 14%, but CNAs affecting RB1 were seen in 34%. Other frequent copy number losses were ARID1A (35%), ESR1 (25%) and ATM (31%). Frequent amplifications/gains were found in MYC (51%) and KDM5A (45%). While these molecular features had limited similarities with SCLC, we found potentially targetable alterations in 66% of the NEC samples. Mutations and CNA varied according to primary tumour site with BRAF mutations mainly seen in colon (49%), and FBXW7 mutations mainly seen in rectal cancers (25%). Eight out of 152 (5.3%) NEC were microsatellite instable (MSI). NET G3 had frequent mutations in MEN1 (21%), ATRX (17%), DAXX, SETD2 and TP53 (each 14%). We show molecular differences in HG GEP-NEN, related to morphological differentiation and site of origin. Limited similarities to SCLC and a high fraction of targetable alterations indicate a high potential for better-personalized treatments.

Room-temperature on-chip orbital angular momentum single-photon sources

Abstract: A room-temperature on-chip orbital angular momentum source that emits well-collimated single photons has been demonstrated.

Full-range birefringence control with piezoelectric MEMS-based metasurfaces

Abstract: Dynamic polarization control is crucial for emerging highly integrated photonic systems with diverse metasurfaces being explored for its realization, but efficient, fast, and broadband operation remains a cumbersome challenge. While efficient optical metasurfaces (OMSs) involving liquid crystals suffer from inherently slow responses, other OMS realizations are limited either in the operating wavelength range (due to resonances involved) or in the range of birefringence tuning. Capitalizing on our development of piezoelectric micro-electro-mechanical system (MEMS) based dynamic OMSs, we demonstrate reflective MEMS-OMS dynamic wave plates (DWPs) with high polarization conversion efficiencies (∼75%), broadband operation (∼100 nm near the operating wavelength of 800 nm), fast responses (<0.4 milliseconds) and full-range birefringence control that enables completely encircling the Poincaré sphere along trajectories determined by the incident light polarization and DWP orientation. Demonstrated complete electrical control over light polarization opens new avenues in further integration and miniaturization of optical networks and systems.

Energy performance contracting in a supply chain with financially asymmetric manufacturers under carbon tax regulation for climate change mitigation

Abstract: Energy performance contracting is a turnkey service for an enterprise to achieve the goal of energy-saving or emission abatement. This study investigates the value of energy performance contracting in a two-echelon supply chain consisting of one supplier and two financially asymmetric manufacturers under carbon tax regulation for climate change mitigation. The supplier provides a trade credit for a financially weak manufacturer who engages in Cournot competition with a financially strong manufacturer. Furthermore, the supplier can act as an energy service company to offer energy performance contracting for the two manufacturers to achieve carbon tax savings. The impact of sharing ratio of energy performance contracting and coefficient of variable cost are analyzed to explore whether and which manufacturer should be chosen by the supplier to implement energy performance contracting. The results suggest that when the coefficient of variable cost is within a high range, the supplier will not provide energy performance contracting for any manufacturer. However, when the coefficient of variable cost and sharing ratio are not very high, the supplier prefers to provide energy performance contracting for the financially weak manufacturer. With the increasing of sharing ratio, the supplier changes the decision to select the financially strong one. Moreover, the model is extended to consider the impact of demand uncertainty and coefficient of investment cost. Furthermore, the result of numerical studies indicates that there exists a Pareto zone for the three supply chain members to achieve a multi-win situation, if the supplier provides the energy performance contracting for both the manufacturers.

The bouba/kiki effect is robust across cultures and writing systems.

Abstract: The bouba/kiki effect-the association of the nonce word bouba with a round shape and kiki with a spiky shape-is a type of correspondence between speech sounds and visual properties with potentially deep implications for the evolution of spoken language. However, there is debate over the robustness of the effect across cultures and the influence of orthography. We report an online experiment that tested the bouba/kiki effect across speakers of 25 languages representing nine language families and 10 writing systems. Overall, we found strong evidence for the effect across languages, with bouba eliciting more congruent responses than kiki. Participants who spoke languages with Roman scripts were only marginally more likely to show the effect, and analysis of the orthographic shape of the words in different scripts showed that the effect was no stronger for scripts that use rounder forms for bouba and spikier forms for kiki. These results confirm that the bouba/kiki phenomenon is rooted in crossmodal correspondence between aspects of the voice and visual shape, largely independent of orthography. They provide the strongest demonstration to date that the bouba/kiki effect is robust across cultures and writing systems. This article is part of the theme issue 'Voice modulation: from origin and mechanism to social impact (Part II)'.

Recent progress in metasurface-enabled optical waveplates

Abstract: Abstract The polarization of light is crucial for numerous optical applications ranging from quantum information processing to biomedical sensing due to the fundamental role of polarization as another intrinsic characteristic of optical waves, which is uncorrelated with the amplitude, phase, and frequency. However, conventional optical waveplates that enable polarization control are based on the accumulated retardation between two orthogonally polarized electric fields when light propagates a distance much larger than its wavelength in birefringent materials, resulting in bulky configurations and limited functionalities. Optical metasurfaces, ultrathin arrays of engineered meta-atoms, have attracted increasing attention owing to their unprecedented capabilities of manipulating light with surface-confined configurations and subwavelength spatial resolutions, thereby opening up new possibilities for revolutionizing bulky optical waveplates with ultrathin planar elements that feature compactness, integration compatibility, broadband operation bandwidths, and multiple functionalities. Herein, we review the recent progress in metasurface-enabled optical waveplates, which covers both basic principles and emerging applications. We provide an overview of metasurface-based conventional half- and quarter-waveplates as well as their use in wavefront shaping applications, followed by a discussion of advanced waveplates, including multifunctional waveplates and all-polarization generators. We also discuss dynamic waveplates based on active metasurfaces. Finally, we conclude by providing our outlook in this emerging and fast-growing research field.

Quantifying supply chain food loss in China with primary data: A large-scale, field-survey based analysis for staple food, vegetables, and fruits

Abstract: Food loss has been widely identified as a key barrier to food security and environmental sustainability in developing countries. However, there remains a lack of empirical studies on the scales and patterns of food loss along the food supply chain in developing countries especially with updated and primary data. In this study, we aim to address this significant gap for China, based on a large-scale field study with questionnaire survey and qualitative interview of 1809 farmer households in 35 major agricultural producing counties of 12 provinces across China between April 2017 and September 2019. Three main agricultural products, staple food, vegetables, and fruits, and their entire supply chain from agricultural production to post-harvest handling, storage, processing, and distribution were covered. The normalized total losses of staple food, vegetables, and fruits added up to 7.9%, 27.7%, and 13.2%, respectively, of their total production. The major loss of staple food occurs at production stage, while post-harvest handling stage and distribution stage, respectively, contribute the most to vegetables and fruits losses. Although China's leapfrogging progress and technology development in recent years have resulted in a reduction of food loss, it was estimated that between 40% and 60% of these losses can still be further mitigated. Such primary data could improve our understanding on the scales and patterns of supply chain food losses in China and thus better inform food loss reduction interventions and associated economic and environmental mitigation strategies.

Single-particle combinatorial multiplexed liposome fusion mediated by DNA

Abstract: Combinatorial high-throughput methodologies are central for both screening and discovery in synthetic biochemistry and biomedical sciences. They are, however, often reliant on large-scale analyses and thus limited by a long running time and excessive materials cost. We here present a single-particle combinatorial multiplexed liposome fusion mediated by DNA for parallelized multistep and non-deterministic fusion of individual subattolitre nanocontainers. We observed directly the efficient (>93%) and leakage free stochastic fusion sequences for arrays of surface-tethered target liposomes with six freely diffusing populations of cargo liposomes, each functionalized with individual lipidated single-stranded DNA and fluorescently barcoded by a distinct ratio of chromophores. The stochastic fusion resulted in a distinct permutation of fusion sequences for each autonomous nanocontainer. Real-time total internal reflection imaging allowed the direct observation of >16,000 fusions and 566 distinct fusion sequences accurately classified using machine learning. The high-density arrays of surface-tethered target nanocontainers (~42,000 containers per mm2) offers entire combinatorial multiplex screens using only picograms of material.

Determinants of Antibody Response to a Third SARS-CoV-2 mRNA Vaccine Dose in Solid Organ Transplant Recipients: Results from the Prospective Cohort Study COVAC-Tx

Abstract: We studied factors related to humoral response in solid organ transplant (SOT) recipients following a three-dose regimen of an mRNA-based SARS-CoV-2 vaccine.This was a prospective study of SOT recipients who received a third homologous dose of the BNT162b2 (Pfizer-BioNTech) vaccine. The anti-spike S1 IgG response was measured using the SARS-CoV-2 IgG II Quant assay (Abbott Laboratories) with a cut-off of 7.1 BAU/mL. Multiple logistic regression was used to determine the factors associated with humoral response.In total, 395 SOT recipients were included. Anti-spike IgG was detected in 195/395 (49.4%) patients after the second dose and 261/335 (77.9%) patients after the third dose. The overall mean increase in antibody concentration after the third dose was 831.0 BAU/mL (95% confidence interval (CI) 687.4-974.5) and 159 (47.5%) participants had at least a 10-fold increase in antibody concentration after the third dose. The increase in antibody concentration was significantly higher among patients with detectable antibodies after the second dose than those without. Cumulative time from transplantation and liver recipients was positively associated with an antibody response, whereas older age, administration of prednisolone, and proliferation inhibitors were associated with diminished antibody response.Although the third dose of the BNT162b2 vaccine improved humoral responses among SOT non-responders following the second dose, the overall response remained low, and 22.1% did not develop any response. Patients at risk of a diminished vaccine response require repeated booster doses and alternative treatment approaches.

Food delivery waste in Wuhan, China: Patterns, drivers, and implications

Abstract: With the rapid development of e-commerce and the modern fast-paced life in large Chinese cities, food delivery services have become an important part of daily life and inevitably result in significant amount of food delivery waste (FDW) and environmental impacts. However, the scales, patterns, and impacts of FDW remain hitherto poorly understood. This study, based on direct weighing method (810 samples) and questionnaire survey (889 samples), aims to address such gaps with a case study for Wuhan, a typical first-tier city in central China. Our results showed that Wuhan's total FDW added up to 177.6 (± 52.9) kilotons in 2019, in which white-collar workers contribute the most (58%) and packaging waste takes up a significant share (32%). When packaging waste is excluded, the amount of FDW varied significantly among consumer groups, i.e., 154 ± 69, 187 ± 97, and 249 ± 124 g/cap/order for urban residents, college students, and white-collar workers, respectively, indicating the predominant role of consumer characteristics on FDW generation. Wuhan's total FDW related carbon emissions were approximately 168.3 kilotons CO2e; and this can be reduced by 25% if waste-to-energy technology can be implemented as planned and by 55% if the avoidable part of FDW can be prevented. Raising awareness and encouraging thriftiness (e.g., via education and public campaigns), nudging and pricing to minimize irrational food purchase, and reducing unnecessary packing and use of disposal dishware, are suggested as important FDW reduction strategies.

An investigation into modelling approaches for industrial symbiosis: A literature review and research agenda

Abstract: Industrial symbiosis is a promising business model that pushes companies to move from linear production to a circular path. However, this transformation is complex because it requires companies to rethink and redesign their supply chains by considering the involvement of new stakeholders, the introduction of waste and their impact on product development, economic investments, and technological resources. As a result, companies need innovative modelling tools able to capture, investigate, and quantify the results of these changes and to work on the strategic planning, design, implementation, and management of their industrial symbiosis networks. This paper presents a systematic literature review to investigate the most used modelling approaches to analyse industrial symbiosis, and to research their characteristics in terms of simulation methods, interaction mechanisms, and simulations software. Findings from our research suggest that an Agent-Based System Dynamics hybrid approach is an appropriate method for industrial symbiosis design and analysis. The paper also presents a theoretical framework that aims at supporting researchers and practitioners approaching industrial symbiosis and, in conclusion, a research agenda is suggested for scholars.