bluuebunny/crossref_metadata_2025 huggingface dataset:
A ROCK Inhibitor Promotes Graft Survival during Transplantation of iPS-Cell-Derived Retinal Cells
Authors: Ishida Masaaki , Sugita Sunao , Makabe Kenichi , Fujii Shota , Futatsugi Yoko , Kamao Hiroyuki , Yamasaki Suguru , Sakai Noriko , Maeda Akiko , Mandai Michiko , Takahashi Masayo
Published: March 2021

Currently, retinal pigment epithelium (RPE) transplantation includes sheet and single-cell transplantation, the latter of which includes cell death and may be highly immunogenic, and there are some issues to be improved in single-cell transplantation. Y-27632 is an inhibitor of Rho-associated protein kinase (ROCK), the downstream kinase of Rho. We herein investigated the effect of Y-27632 in vitro on retinal pigment epithelium derived from induced pluripotent stem cells (iPS-RPE cells), and also its effects in vivo on the transplantation of iPS-RPE cell suspensions. As a result, the addition of Y-27632 in vitro showed suppression of apoptosis, promotion of cell adhesion, and higher proliferation and pigmentation of iPS-RPE cells. Y-27632 also increased the viability of the transplant without showing obvious retinal toxicity in human iPS-RPE transplantation into monkey subretinal space in vivo. Therefore, it is possible that ROCK inhibitors can improve the engraftment of iPS-RPE cell suspensions after transplantation.
Structural Characterization of Receptor–Receptor Interactions in the Allosteric Modulation of G Protein-Coupled Receptor (GPCR) Dimers
Authors: Lazim Raudah , Suh Donghyuk , Lee Jai Woo , Vu Thi Ngoc Lan , Yoon Sanghee , Choi Sun
Published: March 2021

G protein-coupled receptor (GPCR) oligomerization, while contentious, continues to attract the attention of researchers. Numerous experimental investigations have validated the presence of GPCR dimers, and the relevance of dimerization in the effectuation of physiological functions intensifies the attractiveness of this concept as a potential therapeutic target. GPCRs, as a single entity, have been the main source of scrutiny for drug design objectives for multiple diseases such as cancer, inflammation, cardiac, and respiratory diseases. The existence of dimers broadens the research scope of GPCR functions, revealing new signaling pathways that can be targeted for disease pathogenesis that have not previously been reported when GPCRs were only viewed in their monomeric form. This review will highlight several aspects of GPCR dimerization, which include a summary of the structural elucidation of the allosteric modulation of class C GPCR activation offered through recent solutions to the three-dimensional, full-length structures of metabotropic glutamate receptor and γ-aminobutyric acid B receptor as well as the role of dimerization in the modification of GPCR function and allostery. With the growing influence of computational methods in the study of GPCRs, we will also be reviewing recent computational tools that have been utilized to map protein–protein interactions (PPI).
Is High Whitefly Abundance on Cassava in Sub-Saharan Africa Driven by Biological Traits of a Specific, Cryptic Bemisia tabaci Species?
Authors: Mugerwa Habibu , Sseruwagi Peter , Colvin John , Seal Susan
Published: March 2021

In East Africa, the prevalent Bemisia tabaci whiteflies on the food security crop cassava are classified as sub-Saharan Africa (SSA) species. Economically damaging cassava whitefly populations were associated with the SSA2 species in the 1990s, but more recently, it has been to SSA1 species. To investigate whether biological traits (number of first instar nymphs, emerged adults, proportion of females in progeny and development time) of the cassava whitefly species are significant drivers of the observed field abundance, our study determined the development of SSA1 sub-group (SG) 1 (5 populations), SG2 (5 populations), SG3 (1 population) and SSA2 (1 population) on cassava and eggplant under laboratory conditions. SSA1-(SG1-SG2) and SSA2 populations’ development traits were similar. Regardless of the host plant, SSA1-SG2 populations had the highest number of first instar nymphs (60.6 ± 3.4) and emerged adults (50.9 ± 3.6), followed by SSA1-SG1 (55.5 ± 3.2 and 44.6 ± 3.3), SSA2 (45.8 ± 5.7 and 32.6 ± 5.1) and the lowest were SSA1-SG3 (34.2 ± 6.1 and 32.0 ± 7.1) populations. SSA1-SG3 population had the shortest egg–adult emergence development time (26.7 days), followed by SSA1-SG1 (29.1 days), SSA1-SG2 (29.6 days) and SSA2 (32.2 days). Regardless of the whitefly population, development time was significantly shorter on eggplant (25.1 ± 0.9 days) than cassava (34.6 ± 1.0 days). These results support that SSA1-(SG1-SG2) and SSA2 B. tabaci can become highly abundant on cassava, with their species classification alone not correlating with observed abundance and prevalence.
Volunteering in the Citizen Science Project “Insects of Saxony”—The Larger the Island of Knowledge, the Longer the Bank of Questions
Authors: Moczek Nicola , Nuss Matthias , Köhler Jana Katharina
Published: March 2021

In a cross-sectional survey study (N = 116), volunteers of the project Insects of Saxony were asked about their current and past volunteering activities, their motivations, their rating of organisational offers, their knowledge, their satisfaction with the project and their personal contribution, and their intended future involvement. Participants in the study were mostly male, well-educated, over 50 years old, and had been volunteering in biodiversity projects for a long time. They were driven by both pro-social (altruistic) and self-serving (egoistic) motivations, but rated the pro-social functions as more important for their engagement. Communication and feedback were rated the most important organisational offers. Participants also reported a knowledge increase during project participation. While the volunteers were satisfied with the overall project, they were significantly less content with their own contribution. Results from the survey were followed up with a group discussion (N = 60). The anecdotes revealed the participants’ regret of not having more time for their hobby, and they emphasised the challenges that arise from the different scientific approaches of the various disciplines. Most participants indicated that they want to continue their volunteering. Implications for measuring motivations in citizen science projects and for volunteer management are discussed.
Augmenting Nesidiocoris tenuis (Nesidiocoris) with a Factitious Diet of Artemia Cysts to Control Bemisia tabaci (Gennadius) on Tomato Plants under Greenhouse Conditions
Authors: Saito Takeshi , Takagi Motonori , Tezuka Toshiyuki , Ogawara Takashi , Wari David
Published: March 2021

Natural predators such as Nesidiocoris tenuis are known for their role in managing greenhouse pests. However, techniques in maximizing the biological control potential of N. tenuis under field conditions are still lacking. We evaluated under greenhouse conditions the prospects of Artemia cysts enhanced with high fructose corn syrup and honey, and delivered using hemp strings (hemp rope) as supplementary factitious dietary in augmenting the proliferation and spread of N. tenuis on tomato plants. Results showed that N. tenuis supplemented with hemp rope could establish, proliferate and disperse among tomato plants compared to the N. tenuis supplemented with banker plants. Even though N. tenuis proliferated exponentially on banker plants, their movement and relocation to tomato plants, as expected, were only congested on tomato plants near the banker plants. However, as the survey continued, they relocated to the rest of the tomato plants. Furthermore, the number of Bemisia tabaci eggs and nymphs, a serious greenhouse pest of tomato, was observed to be significantly reduced in hemp rope greenhouse compared to banker plants and the negative control (no pest control system) greenhouses. This study, therefore, establishes foundational data on the usage of Artemia cysts enhanced with isomerized sugar (high fructose corn syrup) and honey under greenhouse conditions as factitious supplementary dietary in supporting N. tenuis establishment and spread, traits that are essential towards development of whitefly Integrated Pest Management (IPM) system. enhanced with isomerized sugar (high fructose corn syrup) and honey.
Neelipleona and Symphypleona (Collembola) from a Sampling in the Mesovoid Shallow Substratum of the Sierra de Guadarrama National Park (Madrid and Segovia, Spain): Taxonomy and Biogeography
Authors: Baquero Enrique , Jordana Rafael , Ortuño Vicente M.
Published: March 2021

Megalothorax minimus (Neelidae) and Sphaeridia pumilis (Sminthurididae) had already been identified in surface sampling from Sierra de Guadarrama. In Europe, Sminthurinus gisini (Katiannidae) seems to be associated with environments at specific altitudes, and has little representation in this sampling. Pygmarrhopalites custodum Baquero and Jordana sp. nov. (Arrhopalitidae) coexists with two previously identified surface occurring species of the same family (P. elegans and Arrhopalites caecus). However, P. custodum is more abundant, indicating that it occupies an ecological niche tending to troglophile in the mesovoid shallow substratum (MSS). Moreover, it is also more abundant in the MSS of higher altitude corresponding to the bioclimatic zones cryo-oro-Mediterranean and oro-Mediterranean supra forest. Allacma cryptica Baquero and Jordana sp. nov. (Sminthuridae), is another species that had not been previously detected on the surface in the study area. A. cryptica is an addition to a genus which has eight described species. Gisinurus malatestai (Sminthuridae) appears well represented in the MSS, being a species present very occasionally in the Mediterranean area. Two species of the genera Sminthurides (Sminthurididae) and Fasciosminthurus (Bourletiellidae) have been found, but they could not have been identified to the species level. Finally, a few specimens of Dicyrtomina minuta (Dicyrtomidae), an abundant species on the surface, have been captured.
Comparing the Short-Term Outcome after Polytrauma and Proximal Femur Fracture in Geriatric Patients
Authors: Gather Andreas , Tajima-Schneider Tomoko , Grützner Paul A. , Münzberg Matthias
Published: March 2021

Because of demographic change, geriatric patients are becoming a major challenge for traumatology. Multiple trauma patients and patients with proximal femoral fractures are important groups of patients in geriatric traumatology. This retrospective study compares two patient groups with different severities of injuries, and analyzes their patient characteristics and short-term outcomes, focusing on functionality upon discharge. The investigation aims to present the characterizing features of both patient groups, and to identify the potential risk factors for early functionality after trauma. The patient collective comprises two patient groups: a polytrauma group with 91 patients, and a femoral fracture group with 132 patients. Under the control of potential influencing factors, the present study showed no significant influence of belonging to either of the patient groups (multiple trauma or proximal femoral fracture) on the mobility status at discharge. Age, known dementia, pre-clinical intubation, and the lowest Hb value were identified as significant influencing factors. Despite their old age and vulnerability, the majority of geriatric patients survive accidents. Further prospective investigations concerning the maintenance or restoration of functionality after an accident are therefore desirable.
Rare Forms of Lipomatosis: Dercum’s Disease and Roch-Leri Mesosomatous Lipomatosis
Authors: Lemaitre Madleen , Aubert Sebastien , Chevalier Benjamin , Jannin Arnaud , Bourry Julien , Prévost Gaetan , Lefebvre Herve , Vantyghem Marie-Christine
Published: March 2021

In contrast to obesity, which is very frequent, lipomatosis and lipodystrophy syndromes are rare diseases of adipose tissue. Lipodystrophy syndromes are characterized by metabolic abnormalities associated with partial or generalized lipoatrophy. Lipomatosis is defined by the presence of several body lipomas without lipoatrophy. Dercum’s disease (DD) and Roch-Leri mesosomatous lipomatosis (RLML) are rare and poorly characterized forms of lipomatosis. They have raised little clinical interest despite the non-negligible consequences of DD on quality of life. The main clinical presentation of these diseases includes multiple lipomas, which are painful in DD (in contrast to RLML). The two diseases are frequently associated with obesity and metabolic syndrome, with hypertension, diabetes, or dyslipidemia. The long-term course of the diseases remains poorly described. DD affects mainly women, whereas RLML mostly affects men. In both diseases lipomas are found on the back and thighs, as well as on the abdomen in DD and the forearms in RLML. The painful lipomas tend to recur after surgery in DD (in contrast to RLML). Most cases are sporadic. No specific treatment has been identified, as the pathophysiology remains unknown. Nevertheless, low-grade fat inflammation and specific abnormalities such as hyperbasophilia deserve further investigation. The aim of this review is to analyze the available literature on the topic.
Epigenetic Regulation of Mitochondrial Quality Control Genes in Multiple Myeloma: A Sequenom MassARRAY Pilot Investigation on HMCLs
Authors: D’Aquila Patrizia , Ronchetti Domenica , Gallo Cantafio Maria Eugenia , Todoerti Katia , Taiana Elisa , Fabiani Fernanda , Montesanto Alberto , Neri Antonino , Passarino Giuseppe , Viglietto Giuseppe , Bellizzi Dina , Amodio Nicola
Published: March 2021

The mitochondrial quality control network includes several epigenetically-regulated genes involved in mitochondrial dynamics, mitophagy, and mitochondrial biogenesis under physiologic conditions. Dysregulated expression of such genes has been reported in various disease contexts, including cancer. However, their expression pattern and the possible underlying epigenetic modifications remain to be defined within plasma cell (PC) dyscrasias. Herein, we compared the mRNA expression of mitochondrial quality control genes from multiple myeloma, plasma cell leukemia patients and human myeloma cell lines (HMCLs) with healthy plasma cells; moreover, by applying the Sequenom MassARRAY EpiTYPER technology, we performed a pilot investigation of their CpG methylation status in HMCLs. Overall, the results provided indicate dysregulated expression of several mitochondrial network’s genes, and alteration of the CpG methylation profile, underscoring novel potential myeloma biomarkers deserving in-depth functional investigation in the future.
Copy-Move Forgery Detection (CMFD) Using Deep Learning for Image and Video Forensics
Authors: Rodriguez-Ortega Yohanna , Ballesteros Dora M. , Renza Diego
Published: March 2021

With the exponential growth of high-quality fake images in social networks and media, it is necessary to develop recognition algorithms for this type of content. One of the most common types of image and video editing consists of duplicating areas of the image, known as the copy-move technique. Traditional image processing approaches manually look for patterns related to the duplicated content, limiting their use in mass data classification. In contrast, approaches based on deep learning have shown better performance and promising results, but they present generalization problems with a high dependence on training data and the need for appropriate selection of hyperparameters. To overcome this, we propose two approaches that use deep learning, a model by a custom architecture and a model by transfer learning. In each case, the impact of the depth of the network is analyzed in terms of precision (P), recall (R) and F1 score. Additionally, the problem of generalization is addressed with images from eight different open access datasets. Finally, the models are compared in terms of evaluation metrics, and training and inference times. The model by transfer learning of VGG-16 achieves metrics about 10% higher than the model by a custom architecture, however, it requires approximately twice as much inference time as the latter.
Influence of Wind on Suspended Matter in the Water of the Albufera of Valencia (Spain)
Authors: Soria Juan , Jover Miguel , Domínguez-Gómez José Antonio
Published: March 2021

Wind significantly influences suspended matter in lakes, especially in shallow lagoons. To know how wind affects the water in Albufera of Valencia, a shallow coastal lagoon, the measured variables of turbidity and transparency have been correlated with the estimates by processing Sentinel-2 satellite images with the Sen2Cor processor. Data from four years of study of winds show that most of them are light to gentle easterly breezes and moderate to fresh westerly breezes. The obtained results show significant correlations between the measured variables and those obtained from the satellite images for total suspended matter and water transparency, as well as with the average daily wind speed. There is no significant correlation between wind and chlorophyll a. Moderate to fresh breezes resuspend the fine sediment reaching concentration values from 100 to 300 mg L−1 according to satellite data. However, it is necessary to obtain field data for the values of moderate and fresh winds, as for now, there are no experimental data to verify the validity of the satellite estimates.
Proven Fatal Invasive Aspergillosis in a Patient with COVID-19 and Staphylococcus aureus Pneumonia
Authors: van Someren Gréve Frank , du Long Romy , Talwar Raju , Beurskens Charlotte J. P. , Voerman Huibertus J. , van Dijk Karin
Published: March 2021

There is increasing attention for opportunistic pathogens such as Aspergillus fumigatus complicating SARS-CoV-2 infections in the critically ill. For invasive fungal disease, establishing a clear diagnosis can be challenging due to the invasiveness of diagnostic procedures required for a proven case. Here we present one of the first proven cases of COVID-19-associated pulmonary aspergillosis by positive culture of post-mortem lung biopsy.
In Vitro Activity of Ibrexafungerp against a Collection of Clinical Isolates of Aspergillus, Including Cryptic Species and Cyp51A Mutants, Using EUCAST and CLSI Methodologies
Authors: Rivero-Menendez Olga , Soto-Debran Juan Carlos , Cuenca-Estrella Manuel , Alastruey-Izquierdo Ana
Published: March 2021

Ibrexafungerp is a new orally-available 1,3-β-D-glucan synthesis inhibitor in clinical development. Its in vitro activity and that of amphotericin B, voriconazole, and micafungin were evaluated against a collection of 168 clinical isolates of Aspergillus spp., including azole–susceptible and azole–resistant (Cyp51A mutants) Aspergillus fumigatus sensu stricto (s.s.) and cryptic species of Aspergillus belonging to six species complexes showing different patterns of antifungal resistance, using EUCAST and CLSI antifungal susceptibility testing reference methods. Ibrexafungerp displayed low geometric means of minimal effective concentrations (MECs) against A. fumigatus s.s. strains, both azole susceptible (0.040 mg/L by EUCAST and CLSI versus 1.231 mg/L and 0.660 mg/L for voriconazole, respectively) and azole resistant (0.092 mg/L and 0.056 mg/L, EUCAST and CLSI, while those for voriconazole were 2.144 mg/L and 2.000 mg/L). Ibrexafungerp was active against most of the cryptic species of Aspergillus tested, yielding MEC values only comparable to those of micafungin. Nevertheless, this new compound exhibited a moderate activity against A. ustus complex species, MECs ≥ 0.5 mg/L against Aspergillus insuetus and Aspergillus keveii strains, and was inactive against the Aspergillus alliaceus isolates tested (MEC90s ≥ 16 mg/L). All in all, ibrexafungerp shows encouraging in vitro results against cryptic species of Aspergillus and azole–susceptible and azole resistant strains of A. fumigatus, some of which are difficult to treat using the available therapeutic options.
Prevention of Covid-19 Infection and Related Complications by Ozonized Oils
Authors: Izzotti Alberto , Fracchia Enzo , Au William , Colombo Monica , Pfeffer Ulrich , Emionite Laura , Pavan Simone , Miotto Daniele , Lova Paola , Grasselli Elena , Faelli Emanuela , Piero Ruggeri , Tiso Micaela , Pulliero Alessandra
Published: March 2021

Background: The COVID-19 pandemic continues to ravage the human population; therefore, multiple prevention and intervention protocols are being rapidly developed. The aim of our study was to develop a new chemo-prophylactic/-therapeutic strategy that effectively prevents COVID-19 and related complications. Methods: In in vitro studies, COVID-19 infection-sensitive cells were incubated with human oropharyngeal fluids containing high SARS-CoV-2 loads. Levels of infection were determined via intra-cellular virus loads using quantitative PCR (qPCR). Efficacies for infection prevention were determined using several antiviral treatments: lipid-encapsulated ozonized oil (HOO), water-soluble HOO (HOOws), UV, and hydrogen peroxide. In in vivo studies, safety and efficacy of HOO in fighting COVID-19 infection was evaluated in human subjects. Results: HOO in combination with HOOws was the only treatment able to fully neutralize SARS-CoV-2 as well as its capacity to penetrate and reproduce inside sensitive cells. Accordingly, the feasibility of using HOO/HOOws was tested in vivo. Analysis of expired gas in healthy subjects indicates that HOO administration increases oxygen availability in the lung. For our human studies, HOO/HOOws was administered to 52 cancer patients and 21 healthy subjects at high risk for COVID-19 infection, and all of them showed clinical safety. None of them developed COVID-19 infection, although an incidence of at least 11 cases was expected. Efficacy of HOO/HOOws was tested in four COVID-19 patients obtaining recovery and qPCR negativization in less than 10 days. Conclusions: Based on our experience, the HOO/HOOws treatment can be administered at standard doses (three pills per day) for chemo-prophylactic purposes to healthy subjects for COVID-19 prevention and at high doses (up to eight pills per day) for therapeutic purposes to infected patients. This combined prevention strategy can provide a novel protocol to fight the COVID-19 pandemic.
The 35th Anniversary of the Discovery of EPR Effect: A New Wave of Nanomedicines for Tumor-Targeted Drug Delivery—Personal Remarks and Future Prospects
Authors: Maeda Hiroshi
Published: March 2021

This Special Issue on the enhanced permeability and retention (EPR) effect commemorates the 35th anniversary of its discovery, the original 1986 Matsumura and Maeda finding being published in Cancer Research as a new concept in cancer chemotherapy. My review here describes the history and heterogeneity of the EPR effect, which involves defective tumor blood vessels and blood flow. We reported that restoring obstructed tumor blood flow overcomes impaired drug delivery, leading to improved EPR effects. I also discuss gaps between small animal cancers used in experimental models and large clinical cancers in humans, which usually involve heterogeneous EPR effects, vascular abnormalities in multiple necrotic foci, and tumor emboli. Here, I emphasize arterial infusion of oily formulations of nanodrugs into tumor-feeding arteries, which is the most tumor-selective drug delivery method, with tumor/blood ratios of 100-fold. This method is literally the most personalized medicine because arterial infusions differ for each patient, and drug doses infused depend on tumor size and anatomy in each patient. Future developments in EPR effect-based treatment will range from chemotherapy to photodynamic therapy, boron neutron capture therapy, and therapies for free radical diseases. This review focuses on our own work, which stimulated numerous scientists to perform research in nanotechnology and drug delivery systems, thereby spawning a new cancer treatment era.
The Relationship between Governance Quality and the Cost of Equity Capital in Italian Listed Firms: An Update
Authors: Bertoncelli Francesca , Fandella Paola , Sironi Emiliano
Published: March 2021

This paper investigates the relationship between corporate governance quality and the cost of equity capital, intended as the discount rate the market applies to a firm’s expected future cash flows to evaluate the current share price. Using data from the Italian listed corporations in 2018, this paper combines several attributes like board independence, board size, the existence of the internal audit, and CEO duality incorporated in a corporate governance quality index. Our results do not provide evidence of a statistically significant relationship between the corporate governance score and the firm’s equity capital cost. A possible explanation is that in recent years a greater homogeneity, and a generalized increase in corporate governance quality standards, has been observed in the Italian framework with worse companies that closed the gap with those with higher performances. Hence, lower variability in the corporate governance index results in a not significant effect of a composite index on reducing the cost of equity capital.
Evaluating the Impact of Large-Scale Agricultural Investments on Household Food Security Using an Endogenous Switching Regression Model
Authors: Fitawek Wegayehu , Hendriks Sheryl
Published: March 2021

This study set out to estimate the effects of large-scale agricultural investments (LSAIs) on household food security in one community each in Kenya, Madagascar and Mozambique. An endogenous switching regression model was adopted to control for a possible selection bias due to unobserved factors. It was found that households with members employed by large-scale agricultural investment companies were more likely larger households headed by younger migrant males holding smaller plots and fewer livestock than non-engaged households. The endogenous switching regression results confirmed the presence of both a positive and negative selection bias. In general, the results showed that households with a member employed by an LSAI enjoyed better household food security, higher dietary diversity, better food consumption scores and more adequate household food provisioning. Households without employed members could also enjoy these benefits should the LSAIs employ their members. However, the seasonal nature and low wages paid by LSAI may only support the purchase of food and not facilitate savings and investments to significantly improve food security.
Global Land Grabbing: A Critical Review of Case Studies across the World
Authors: Yang Bin , He Jun
Published: March 2021

Over the past several decades, land investments have dramatically increased to meet global food and biofuel demands, produce industrial commodities, protect environments and develop urban centres. Scholars and media actors have labelled this phenomenon “land grabbing”, owing to its many negative impacts. Since existing knowledge was generated from individual case-studies, global land grabbing patterns are relatively underexamined, and broader extrapolations of results to inform land grabbing theories are limited. Thus, there is an urgent need to conduct a large-N analyse on existing knowledge of land grabbing to enhance the understanding of the state-of-the-art knowledge and identify the gaps in research. We conducted a critical review of existing scholarly literature on case studies of land grabbing. Based on formal criteria, we selected 128 case studies from 124 articles out of 252 peer-reviewed articles published since 2007. We examined geographic distribution and commonly referenced topics in existing research and the clarified environmental and socioeconomic outcomes of land grabbing, presenting the most current knowledge on the topic to date. Findings from this research also revealed substantial gaps in the existing literature in terms of conceptualization, methodology and research area. The paper concludes with a call for more interdisciplinary, holistic research that looks at broader regional/temporal contexts and the inclusion of more evidence-based data.
Digitization as a Driver fur Rural Development—An Indicative Description of German Coworking Space Users
Authors: Hölzel Marco , de Vries Walter Timo
Published: March 2021

Background: The urban-rural land divide is visible through where people choose to work. This article aims to detect how, where and why people use rural coworking spaces instead of or in addition to working in urban areas. Methods: The research relied on both documented evidence and a structured survey among users of coworking spaces. Results: We found that the choice of working in rural coworking spaces draws on certain benefits and opportunities for its users, such as avoiding social isolation, separating private and professional life, reducing the commuting. An additional benefit for rural towns and villages is that the presence of a coworking space can make the location more vital, lively and attractive. Conclusions (and recommendations): Coworking space could partially bridge the urban-rural land divide. However, understanding this requires more insights in the behavior of rural coworking space users. Further research could look into modelling cause-effect relations and predicting coworking user behavior and the effect on their environment.
Regular and Irregular Inflection in Different Groups of Bilingual Children and the Role of Verbal Short-Term and Verbal Working Memory
Authors: Blom Elma , Bosma Evelyn , Heeringa Wilbert
Published: March 2021

Bilingual children often experience difficulties with inflectional morphology. The aim of this longitudinal study was to investigate how regularity of inflection in combination with verbal short-term and working memory (VSTM, VWM) influences bilingual children’s performance. Data from 231 typically developing five- to eight-year-old children were analyzed: Dutch monolingual children (N = 45), Frisian-Dutch bilingual children (N = 106), Turkish-Dutch bilingual children (N = 31), Tarifit-Dutch bilingual children (N = 38) and Arabic-Dutch bilingual children (N = 11). Inflection was measured with an expressive morphology task. VSTM and VWM were measured with a Forward and Backward Digit Span task, respectively. The results showed that, overall, children performed more accurately at regular than irregular forms, with the smallest gap between regulars and irregulars for monolinguals. Furthermore, this gap was smaller for older children and children who scored better on a non-verbal intelligence measure. In bilingual children, higher accuracy at using (irregular) inflection was predicted by a smaller cross-linguistic distance, a larger amount of Dutch at home, and a higher level of parental education. Finally, children with better VSTM, but not VWM, were more accurate at using regular and irregular inflection.
The Case (or Not) for Life in the Venusian Clouds
Authors: Schulze-Makuch Dirk
Published: March 2021

The possible detection of the biomarker of phosphine as reported by Greaves et al. in the Venusian atmosphere stirred much excitement in the astrobiology community. While many in the community are adamant that the environmental conditions in the Venusian atmosphere are too extreme for life to exist, others point to the claimed detection of a convincing biomarker, the conjecture that early Venus was doubtlessly habitable, and any Venusian life might have adapted by natural selection to the harsh conditions in the Venusian clouds after the surface became uninhabitable. Here, I first briefly characterize the environmental conditions in the lower Venusian atmosphere and outline what challenges a biosphere would face to thrive there, and how some of these obstacles for life could possibly have been overcome. Then, I discuss the significance of the possible detection of phosphine and what it means (and does not mean) and provide an assessment on whether life may exist in the temperate cloud layer of the Venusian atmosphere or not.
Brain Insulin Resistance: Focus on Insulin Receptor-Mitochondria Interactions
Authors: Pomytkin Igor , Pinelis Vsevolod
Published: March 2021

Current hypotheses implicate insulin resistance of the brain as a pathogenic factor in the development of Alzheimer’s disease and other dementias, Parkinson’s disease, type 2 diabetes, obesity, major depression, and traumatic brain injury. A variety of genetic, developmental, and metabolic abnormalities that lead to disturbances in the insulin receptor signal transduction may underlie insulin resistance. Insulin receptor substrate proteins are generally considered to be the node in the insulin signaling system that is critically involved in the development of insulin insensitivity during metabolic stress, hyperinsulinemia, and inflammation. Emerging evidence suggests that lower activation of the insulin receptor (IR) is another common, while less discussed, mechanism of insulin resistance in the brain. This review aims to discuss causes behind the diminished activation of IR in neurons, with a focus on the functional relationship between mitochondria and IR during early insulin signaling and the related roles of oxidative stress, mitochondrial hypometabolism, and glutamate excitotoxicity in the development of IR insensitivity to insulin.
Microencapsulated Phase Change Material Suspension for Cold Start of PEMFC
Authors: Chen Sitong , Wang Shubo , Wang Xueke , Li Weiwei , Liang Baorui , Zhu Tong , Xie Xiaofeng
Published: March 2021

We added microencapsulated phase change materials (MPCMs) into the homemade antifreeze fluid to take advantage of the latent heat of phase change materials, and explored the possibility of solving the cold start problem of proton exchange membrane fuel cells (PEMFC) with variable specific heat capacity antifreeze. The physical and chemical properties of the MPCMs and their suspensions were tested, and a PEMFC platform for cold start with a thermal management system was established to compare the exothermic performance of MPCS and commercial antifreeze fluid. According to the output voltage, temperature and polarization curves before and after cold start, the MPCMs has a stronger heat transfer capacity than the commercial antifreeze fluid, and the addition of MPCMs can transform the latent heat generated during the phase transition into apparent specific heat capacity, leading to a better solution to the problem of PEMFC cold start.
UHMWPE-Based Glass-Fiber Composites Fabricated by FDM. Multiscaling Aspects of Design, Manufacturing and Performance
Authors: Panin Sergey V. , Buslovich Dmitry G. , Dontsov Yuri V. , Bochkareva Svetlana A. , Kornienko Lyudmila A. , Berto Filippo
Published: March 2021

The aim of the paper was to improve the functional properties of composites based on ultra-high molecular weight polyethylene (UHMWPE) by loading with reinforcing fibers. It was achieved by designing the optimal composition for its subsequent use as a feedstock for 3D-printing of guides for roller and plate chains, conveyors, etc. As a result, it was experimentally determined that loading UHMWPE with 17% high density polyethylene grafted with VinylTriMethoxySilane (HDPE-g-VTMS) was able to bind 5% glass fillers of different aspect ratios, thereby determining the optimal mechanical and tribological properties of the composites. Further increasing the content of the glass fillers caused a deterioration in their tribological properties due to insufficient adhesion of the extrudable matrix due to the excessive filler loading. A multi-level approach was implemented to design the high-strength anti-friction ‘UHMWPE+17%HDPE-g-VTMS+12%PP’-based composites using computer-aided algorithms. This resulted in the determination of the main parameters that provided their predefined mechanical and tribological properties and enabled the assessment of the possible load-speed conditions for their operation in friction units. The uniform distribution of the fillers in the matrix, the pattern of the formed supermolecular structure and, as a consequence, the mechanical and tribological properties of the composites were achieved by optimizing the values of the main control parameters (the number of processing passes in the extruder and the aspect ratio of the glass fillers).
In-Plane Shear Strength of Single-Lap Co-Cured Joints of Self-Reinforced Polyethylene Composites
Authors: Vannucchi de Camargo Felipe , da Silva Fernandes Eduardo , ten Caten Carla Schwengber , Alves Annelise Kopp , Bergmann Carlos Pérez , Minak Giangiacomo
Published: March 2021

The present study introduces the analysis of single-lap co-cured joints of thermoplastic self-reinforced composites made with reprocessed low-density polyethylene (LDPE) and reinforced by ultra-high-molecular-weight polyethylene (UHMWPE) fibers, along with a micromechanical analysis of its constituents. A set of optimal processing conditions for manufacturing these joints by hot-press is proposed through a design of experiment using the response surface method to maximize their in-plane shear strength by carrying tensile tests on co-cured tapes. Optimal processing conditions were found at 1 bar, 115 °C, and 300 s, yielding joints with 6.88 MPa of shear strength. The shear failure is generally preceded by multiple debonding-induced longitudinal cracks both inside and outside the joint due to accumulated transversal stress. This composite demonstrated to be an interesting structural material to be more widely applied in industry, possessing extremely elevated specific mechanical properties, progressive damage of co-cured joints (thus avoiding unannounced catastrophic failures) and ultimate recyclability.
Structural Response of Steel Jacket-UHPC Retrofitted Reinforced Concrete Columns under Blast Loading
Authors: Hanifehzadeh Mohammad , Aryan Hadi , Gencturk Bora , Akyniyazov Dovlet
Published: March 2021

The lateral capacity of exterior concrete columns subjected to a blast load is the key factor in the building collapse probability. Due to potentially severe consequences of the collapse, efforts have been made to improve the blast resistance of existing structures. One of the successful approaches is the use of ultra-high-performance-concrete (UHPC) jacketing for retrofitting a building’s columns. The columns on the first floor of a building normally have higher slenderness due to the higher first story. Since an explosion is more likely to take place at the ground level, retrofitting the columns of the lower floors is crucial to improve a building’s blast resistance. Casting a UHPC tube around a circular RC column can increase the moment of inertia of the column and improve the flexural strength. In this study, a retrofitting system consisting of a UHPC layer enclosed by a thin steel jacket is proposed to improve the blast resistance of buildings in service. Most of the previous research is focused on design aspects of blast-resistant columns and retrofitting systems are mostly based on fiber reinforced polymers or steel jackets. A validated FE model is used to investigate the effectiveness of this method. The results showed significant improvement both at the component and building system levels against combined gravity and blast loading.
Mechanical and Adsorptive Properties of Foamed EVA-Modified Polypropylene/Bamboo Charcoal Composites
Authors: Li Wenzhu , Zhang Jing , Huang Jingda , Shao Yuanchao , Zhang Wenbiao , Dai Chunping
Published: March 2021

Due to its excellent adsorption and humidity control function, bamboo charcoal (BC) has often been mixed with polypropylene (PP) to produce PP/BC composites for interior paneling applications. However, due to the poor foaming quality of PP, PP/BC composites suffer as a result of their high density, which limits their scope of use. Here, to improve its foaming quality, PP was modified with ethylene vinyl acetate (EVA), and then the EVA-modified PP (E-PP) was mixed with different contents of BC (0 wt.%–50 wt.%), as well as foaming agent (Azodicarbonamide, AC) and its auxiliaries (ZnO, Znst), in a twin-screw extruder, followed by hot-pressing at high temperature to obtain foamed E-PP/BC composites. The resulting composites showed good porosity and pore distribution with an increase of BC content by up to 20%. Further increase in the BC content seemed to cause the foaming performance to decrease significantly. The product density and adsorption rate increased, while the mechanical strength decreased with increasing BC content. At a BC content of 40 wt.%, the foamed E-PP/BC composite showed the best combined performance, with a density of 0.90 g/cm3, 24-h formaldehyde adsorption rate of 0.48, and bending strength of 11.59 MPa.
Damage Evolution and Fracture Behavior of C/SiC Minicomposites with Different Interphases under Uniaxial Tensile Load
Authors: Zhang Zhongwei , Li Longbiao , Chen Zhaoke
Published: March 2021

In this paper, the tensile damage and fracture behavior of carbon fiber reinforced silicon carbide (C/SiC) minicomposites with single- and multiple-layer interphases are investigated. The effect of the interphase on the tensile damage and fracture behavior of C/SiC minicomposites is analyzed. The evolution of matrix cracking under the tensile load of the C/SiC minicomposite with a notch is observed using the digital image correlation (DIC) method. The damage evolution process of the C/SiC minicomposite can be divided into four main stages, namely, (1) an elastic response coupled with partial re-opening of thermal microcracking; (2) multiple matrix microcracking perpendicular to the applied loading; (3) crack opening and related fiber/matrix, bundle/matrix, and inter-bundle debonding; and (4) progressive transfer of the load to the fibers and gradual fiber failure until composite failure/fracture. On the fracture surface, a large number of fibers pulling out of the samples with both single-layer and multi-layer interphases can be clearly observed.
Chemical and Structural Characterization of Maize Stover Fractions in Aspect of Its Possible Applications
Authors: Woźniak Magdalena , Ratajczak Izabela , Wojcieszak Dawid , Waśkiewicz Agnieszka , Szentner Kinga , Przybył Jacek , Borysiak Sławomir , Goliński Piotr
Published: March 2021

In the last decade, an increasingly common method of maize stover management is to use it for energy generation, including anaerobic digestion for biogas production. Therefore, the aim of this study was to provide a chemical and structural characterization of maize stover fractions and, based on these parameters, to evaluate the potential application of these fractions, including for biogas production. In the study, maize stover fractions, including cobs, husks, leaves and stalks, were used. The biomass samples were characterized by infrared spectroscopy (FTIR), X-ray diffraction and analysis of elemental composition. Among all maize stover fractions, stalks showed the highest C:N ratio, degree of crystallinity and cellulose and lignin contents. The high crystallinity index of stalks (38%) is associated with their high cellulose content (44.87%). FTIR analysis showed that the spectrum of maize stalks is characterized by the highest intensity of bands at 1512 cm−1 and 1384 cm−1, which are the characteristic bands of lignin and cellulose. Obtained results indicate that the maize stover fraction has an influence on the chemical and structural parameters. Moreover, presented results indicate that stalks are characterized by the most favorable chemical parameters for biogas production.
Ce/Sm/Sr-Incorporating Ceramic Scaffolds Obtained via Sol-Gel Route
Authors: Jinga Sorin-Ion , Anghel Ana-Maria , Brincoveanu Silvia-Florena , Bucur Raluca-Maria , Florea Andrei-Dan , Saftau Bianca-Irina , Stroe Stefania-Cristina , Zamfirescu Andreea-Ioana , Busuioc Cristina
Published: March 2021

Three different inorganic scaffolds were obtained starting from the oxide system SiO2‒P2O5‒CaO‒MgO, to which Ce4+/Sm3+/Sr2+ cations were added in order to propose novel materials with potential application in the field of hard tissue engineering. Knowing the beneficial effects of each element, improved features in terms of mechanical properties, antibacterial activity and cellular response are expected. The compositions were processed in the form of scaffolds by a common sol-gel method, followed by a thermal treatment at 1000 and 1200 °C. The obtained samples were characterized from thermal, compositional, morphological and mechanical point of view. It was shown that each supplementary component triggers the modification of the crystalline phase composition, as well as microstructural details. Moreover, the shrinkage behavior is well correlated with the attained compression strength values. Sm was proven to be the best choice, since in addition to a superior mechanical resistance, a clear beneficial influence on the viability of 3T3 fibroblast cell line was observed.
Durability of Epoxy Adhesives and Carbon Fibre Reinforced Polymer Laminates Used in Strengthening Systems: Accelerated Ageing versus Natural Ageing
Authors: Cruz Ricardo , Correia Luís , Dushimimana Aloys , Cabral-Fonseca Susana , Sena-Cruz José
Published: March 2021

This work addresses the durability of structural epoxy adhesives and carbon fibre reinforced polymer (CFRP) laminates typically used in strengthening of existing reinforced concrete structures exposed to natural ageing. The experimental program included four natural (real) outdoor environments inducing ageing mainly caused by carbonation, freeze-thaw attack, elevated temperatures, and airborne chlorides from seawater. Moreover, a control (reference) environment (20 °C of temperature and 55% of relative humidity) and an environment involving water immersion of the materials under controlled temperature (20 °C of temperature) were also included in this investigation. The characterization involved the assessment of the physical, chemical and mechanical properties along a study period of up to two years. Furthermore, comparisons between the natural ageing tests developed in the scope of the present work and accelerated ageing tests existing in the literature were performed. Regarding to the epoxy adhesives, an increase in the glass transition temperature with the time was observed, while the tensile properties decreased, regardless of the outdoor environment. The CFRP laminates were marginally affected by the studied environments. Despite the remarkable dispersion of the results observed in the accelerated ageing tests for the period investigated, this testing protocol yielded higher mechanical degradation than under natural ageing.
Performance Enhancement in N2 Plasma Modified AlGaN/AlN/GaN MOS-HEMT Using HfAlOX Gate Dielectric with Γ-Shaped Gate Engineering
Authors: Yang Shun-Kai , Mazumder Soumen , Wu Zhan-Gao , Wang Yeong-Her
Published: March 2021

In this paper, we have demonstrated the optimized device performance in the Γ-shaped gate AlGaN/AlN/GaN metal oxide semiconductor high electron mobility transistor (MOS-HEMT) by incorporating aluminum into atomic layer deposited (ALD) HfO2 and comparing it with the commonly used HfO2 gate dielectric with the N2 surface plasma treatment. The inclusion of Al in the HfO2 increased the crystalline temperature (~1000 °C) of hafnium aluminate (HfAlOX) and kept the material in the amorphous stage even at very high annealing temperature (>800 °C), which subsequently improved the device performance. The gate leakage current (IG) was significantly reduced with the increasing post deposition annealing (PDA) temperature from 300 to 600 °C in HfAlOX-based MOS-HEMT, compared to the HfO2-based device. In comparison with HfO2 gate dielectric, the interface state density (Dit) can be reduced significantly using HfAlOX due to the effective passivation of the dangling bond. The greater band offset of the HfAlOX than HfO2 reduces the tunneling current through the gate dielectric at room temperature (RT), which resulted in the lower IG in Γ-gate HfAlOX MOS-HEMT. Moreover, IG was reduced more than one order of magnitude in HfAlOX MOS-HEMT by the N2 surface plasma treatment, due to reduction of N2 vacancies which were created by ICP dry etching. The N2 plasma treated Γ-shaped gate HfAlOX-based MOS-HEMT exhibited a decent performance with IDMAX of 870 mA/mm, GMMAX of 118 mS/mm, threshold voltage (VTH) of −3.55 V, higher ION/IOFF ratio of approximately 1.8 × 109, subthreshold slope (SS) of 90 mV/dec, and a high VBR of 195 V with reduced gate leakage current of 1.3 × 10−10 A/mm.