bluuebunny/crossref_metadata_2025 huggingface dataset:
Treadmill Exercise Buffers Behavioral Alterations Related to Ethanol Binge-Drinking in Adolescent Mice
Authors: Sampedro-Piquero Patricia , Millón Carmelo , Moreno-Fernández Román D. , García-Fernández María , Diaz-Cabiale Zaida , Santin Luis Javier
Published: August 2020

The binge-drinking pattern of EtOH consumption, which is frequently observed in adolescents, is known to induce several neurobehavioral alterations, but protection strategies against these impairments remain scarcely explored. We aimed to study the protective role of treadmill physical exercise on the deficits caused after repeated cycles of binge-like EtOH exposure in the cognition, motivation, exploration, and emotion of C57BL/6J mice from adolescence to adulthood. Animals were divided into four groups: control group, exercised group, EtOH group, and exercised + EtOH group (20% in tap water). The exercise was performed for 20 min, 5 days/week at 20 cm/s. Then, animals were submitted to several behavioral tasks. Compared to binge-drinking mice, the exercised + EtOH group exhibited diminished anxiolytic-related behaviors in the elevated plus-maze, enhanced exploratory activity in the open field, reduced preference for alcohol odor when another rewarding stimulus was present (social stimulus) and lower latency to start self-cleaning behaviors in the sucrose splash test. In contrast, other measurements such as habituation learning and working memory were not improved by exercise. Besides, exercise was not able to reduce alcohol consumption across the weeks. In conclusion, physical activity during adolescence and early adulthood could buffer certain neurobehavioral alterations associated with binge-drinking, despite not reducing the quantity of consumed alcohol.
The Full Blood Count Blood Test for Colorectal Cancer Detection: A Systematic Review, Meta-Analysis, and Critical Appraisal
Authors: Virdee Pradeep S. , Marian Ioana R. , Mansouri Anita , Elhussein Leena , Kirtley Shona , Holt Tim , Birks Jacqueline
Published: August 2020

Introduction: A full blood count (FBC) blood test includes 20 components. We systematically reviewed studies that assessed the association of the FBC and diagnosis of colorectal cancer to identify components as risk factors. We reviewed FBC-based prediction models for colorectal cancer risk. Methods: MEDLINE, EMBASE, CINAHL, and Web of Science were searched until 3 September 2019. We meta-analysed the mean difference in FBC components between those with and without a diagnosis and critically appraised the development and validation of FBC-based prediction models. Results: We included 53 eligible articles. Three of four meta-analysed components showed an association with diagnosis. In the remaining 16 with insufficient data for meta-analysis, three were associated with colorectal cancer. Thirteen FBC-based models were developed. Model performance was commonly assessed using the c-statistic (range 0.72–0.91) and calibration plots. Some models appeared to work well for early detection but good performance may be driven by early events. Conclusion: Red blood cells, haemoglobin, mean corpuscular volume, red blood cell distribution width, white blood cell count, and platelets are associated with diagnosis and could be used for referral. Existing FBC-based prediction models might not perform as well as expected and need further critical testing.
Targeting the Calcium Signalling Machinery in Cancer
Authors: Bruce Jason I. E. , James Andrew D.
Published: August 2020

Cancer is caused by excessive cell proliferation and a propensity to avoid cell death, while the spread of cancer is facilitated by enhanced cellular migration, invasion, and vascularization. Cytosolic Ca2+ is central to each of these important processes, yet to date, there are no cancer drugs currently being used clinically, and very few undergoing clinical trials, that target the Ca2+ signalling machinery. The aim of this review is to highlight some of the emerging evidence that targeting key components of the Ca2+ signalling machinery represents a novel and relatively untapped therapeutic strategy for the treatment of cancer.
Low Incidence of SARS-CoV-2 in Patients with Solid Tumours on Active Treatment: An Observational Study at a Tertiary Cancer Centre in Lombardy, Italy
Authors: Bertuzzi Alexia Francesca , Marrari Andrea , Gennaro Nicolò , Cariboni Umberto , Ciccarelli Michele , Giordano Laura , Quagliuolo Vittorio Lorenzo , Santoro Armando
Published: August 2020

Background: The incidence and prognosis of SARS-CoV-2-positive cancer patients on active oncologic treatment remain unknown. Retrospective data from China reported higher incidence and poorer outcomes with respect to the general population. We aimed to describe the real-word incidence of SARS-CoV-2 in cancer patients and the impact of oncologic therapies on the infection. Materials & Methods: In this study, we analysed all consecutive cancer patients with solid tumours undergoing active intravenous treatment (chemotherapy, immunotherapy, targeted therapy, alone or in combination) between 21 February and 30 April 2020, in a high-volume cancer centre in Lombardy, Italy. We focused on SARS-CoV-2-positive patients, reporting on the clinical characteristics of the cancer and the infection. Results: We registered 17 SARS-CoV-2-positive patients among 1267 cancer patients on active treatment, resulting in an incidence of 1.3%. The median age was 69.5 years (range 43–79). Fourteen patients (82%) required hospitalisation for COVID-19 with a median in-hospital stay of 11.5 days (range 3–58). Fourteen of the seventeen (82%) were treated for locally advanced or metastatic disease. We could not demonstrate any correlation between SARS-CoV-2 infection and tumour or treatment type. The COVID-19-related fatality rate was 29% (5/17), which was higher than that of the general population cared for in our centre (20%). Conclusions: Active oncologic treatments do not represent a risk factor for SARS-CoV-2 infection in cancer patients. However, the prognosis of infected cancer patients appears to be worse compared with that of the non-oncologic population. Given the low number of SARS-CoV-2-positive cases and the uncertainties in risk factors that may have an impact on the prognosis, we advocate for the continuum of cancer care even during the current pandemic.
Targeted and Checkpoint Inhibitor Therapy of Metastatic Malignant Melanoma in Germany, 2000–2016
Authors: Hellmund Peter , Schmitt Jochen , Roessler Martin , Meier Friedegund , Schoffer Olaf
Published: August 2020

Targeted therapies (TT) and immune checkpoint inhibitors (ICI) have become increasingly important in the treatment of metastatic malignant melanoma in recent years. We examined implementation and effectiveness of these new therapies over time in Germany with a focus on regional differences. We analyzed data from 12 clinical cancer registries in 8 federal states in Germany over the period 2000–2016. A total of 3871 patients with malignant melanoma in Union internationale contre le cancer (UICC) stage IV at primary diagnosis (synchronous metastases) or with metachronous metastases were included. We investigated differences in survival of patients treated with new and conventional therapies by log-rank tests for Kaplan–Meier curves. Cox regression models were estimated to adjust therapy effects for demographic, regional, and prognostic factors. New systemic therapies were increasingly applied throughout Germany. TT were most frequently documented in Eastern Germany (East: 11.2%; West: 6.3%), whereas ICI therapies were more frequently used in Western Germany (East: 1.7%; West: 3.9%). TT had a relevant influence on patient survival (hazard ratio (HR) = 0.831; 95%-CI = (0.729; 0.948)). Survival was worse in Eastern Germany (HR = 1.470; 95%-CI = (1.347; 1.604)) relative to Western Germany. Treatment and survival prospects of patients with melanoma differed considerably between Western and Eastern Germany. The differences in regional medication behavior and survival require further exploration.
Beta Human Papillomavirus 8E6 Attenuates Non-Homologous End Joining by Hindering DNA-PKcs Activity
Authors: Hu Changkun , Bugbee Taylor , Gamez Monica , Wallace Nicholas A.
Published: August 2020

Cutaneous viral infections occur in a background of near continual exposure to environmental genotoxins, like UV radiation in sunlight. Failure to repair damaged DNA is an established driver of tumorigenesis and substantial cellular resources are devoted to repairing DNA lesions. Beta-human papillomaviruses (β-HPVs) attenuate DNA repair signaling. However, their role in human disease is unclear. Some have proposed that β-HPV promotes tumorigenesis, while others suggest that β-HPV protects against skin cancer. Most of the molecular evidence that β-HPV impairs DNA repair has been gained via characterization of the E6 protein from β-HPV 8 (β-HPV 8E6). Moreover, β-HPV 8E6 hinders DNA repair by binding and destabilizing p300, a transcription factor for multiple DNA repair genes. By reducing p300 availability, β-HPV 8E6 attenuates a major double strand DNA break (DSB) repair pathway, homologous recombination. Here, β-HPV 8E6 impairs another DSB repair pathway, non-homologous end joining (NHEJ). Specifically, β-HPV 8E6 acts by attenuating DNA-dependent protein kinase (DNA-PK) activity, a critical NHEJ kinase. This includes DNA-PK activation and the downstream of steps in the pathway associated with DNA-PK activity. Notably, β-HPV 8E6 inhibits NHEJ through p300 dependent and independent means. Together, these data expand the known genome destabilizing capabilities of β-HPV 8E6.
Iron-Loaded Catalytic Silicate Adsorbents: Synthesis, Characterization, Electroregeneration and Application for Continuous Removal of 1-Butylpyridinium Chloride
Authors: Ouiriemmi Imen , Díez Aida M. , Pazos Marta , Sanromán María Ángeles
Published: August 2020

This research proposes the application of iron-loaded sepiolite (S-Fe) as a catalytic adsorbent for the unreported 1-butylpyridinium chloride ([bpy] Cl) treatment in an aqueous medium. Initially, sepiolite was selected as an inexpensive and efficacious adsorbent for [bpy] Cl elimination. After that, sepiolite was loaded with iron for the subsequent electro-Fenton (EF) regeneration treatment. Once kinetic and isotherm studies were performed, providing respectively almost instantaneous adsorption (20 min) and an uptake of 22.85 mg/g, [bpy] Cl adsorption onto S-Fe was studied in continuous mode. The obtained breakthrough curve was analyzed using three standard breakthrough models, being Yoon–Nelson and Thomas the most suitable adjustments. Afterwards, S-Fe regeneration by the EF process was conducted using this iron-loaded silicate material as a heterogeneous catalyst. Under optimized operational conditions (current intensity 300 mA and Na2SO4 0.3 M), complete adsorbent regeneration was achieved in 10 h. The total mineralization of [bpy] Cl was reached within 24 h and among seven carboxylic acids detected, oxalic and acetic acids seem to be the primary carboxylic acids produced by [bpy] Cl degradation. Finally, S-Fe was efficiently used in four consecutive adsorption–regeneration cycles without a noticeable reduction in its adsorption capacity, opening a path for future uses.
Biocatalytic Oxidation of Alcohols
Authors: Puetz Hendrik , Puchľová Eva , Vranková Kvetoslava , Hollmann Frank
Published: August 2020

Enzymatic methods for the oxidation of alcohols are critically reviewed. Dehydrogenases and oxidases are the most prominent biocatalysts, enabling the selective oxidation of primary alcohols into aldehydes or acids. In the case of secondary alcohols, region and/or enantioselective oxidation is possible. In this contribution, we outline the current state-of-the-art and discuss current limitations and promising solutions.
Recent Advances on Copper Complexes as Visible Light Photoinitiators and (Photo) Redox Initiators of Polymerization
Authors: Noirbent Guillaume , Dumur Frédéric
Published: August 2020

Metal complexes are used in numerous chemical and photochemical processes in organic chemistry. Metal complexes have not been excluded from the interest of polymerists to convert liquid resins into solid materials. If iridium complexes have demonstrated their remarkable photochemical reactivity in polymerization, their high costs and their attested toxicities have rapidly discarded these complexes for further developments. Conversely, copper complexes are a blooming field of research in (photo) polymerization due to their low cost, easy syntheses, long-living excited state lifetimes, and their remarkable chemical and photochemical stabilities. Copper complexes can also be synthesized in solution and by mechanochemistry, paving the way towards the synthesis of photoinitiators by Green synthetic approaches. In this review, an overview of the different copper complexes reported to date is presented. Copper complexes are versatile candidates for polymerization, as these complexes are now widely used not only in photopolymerization, but also in redox and photoassisted redox polymerization processes.
Altered Expression Ratio of Actin-Binding Gelsolin Isoforms Is a Novel Hallmark of Mitochondrial OXPHOS Dysfunction
Authors: García-Bartolomé Alberto , Peñas Ana , Illescas María , Bermejo Verónica , López-Calcerrada Sandra , Pérez-Pérez Rafael , Marín-Buera Lorena , Domínguez-González Cristina , Arenas Joaquín , Martín Miguel A. , Ugalde Cristina
Published: August 2020

Mitochondrial oxidative phosphorylation (OXPHOS) defects are the primary cause of inborn errors of energy metabolism. Despite considerable progress on their genetic basis, their global pathophysiological consequences remain undefined. Previous studies reported that OXPHOS dysfunction associated with complex III deficiency exacerbated the expression and mitochondrial location of cytoskeletal gelsolin (GSN) to promote cell survival responses. In humans, besides the cytosolic isoform, GSN presents a plasma isoform secreted to extracellular environments. We analyzed the interplay between both GSN isoforms in human cellular and clinical models of OXPHOS dysfunction. Regardless of its pathogenic origin, OXPHOS dysfunction induced the physiological upregulation of cytosolic GSN in the mitochondria (mGSN), in parallel with a significant downregulation of plasma GSN (pGSN) levels. Consequently, significantly high mGSN-to-pGSN ratios were associated with OXPHOS deficiency both in human cells and blood. In contrast, control cells subjected to hydrogen peroxide or staurosporine treatments showed no correlation between oxidative stress or cell death induction and the altered levels and subcellular location of GSN isoforms, suggesting their specificity for OXPHOS dysfunction. In conclusion, a high mitochondrial-to-plasma GSN ratio represents a useful cellular indicator of OXPHOS defects, with potential use for future research of a wide range of clinical conditions with mitochondrial involvement.
Microcurrent Stimulation Triggers MAPK Signaling and TGF-β1 Release in Fibroblast and Osteoblast-Like Cell Lines
Authors: Konstantinou Evangelia , Zagoriti Zoi , Pyriochou Anastasia , Poulas Konstantinos
Published: August 2020

Wound healing constitutes an essential process for all organisms and involves a sequence of three phases. The disruption or elongation of any of these phases can lead to a chronic or non-healing wound. Electrical stimulation accelerates wound healing by mimicking the current that is generated in the skin after any injury. Here, we sought to identify the molecular mechanisms involved in the healing process following in vitro microcurrent stimulation—a type of electrotherapy. Our results concluded that microcurrents promote cell proliferation and migration in an ERK 1/2- or p38-dependent way. Furthermore, microcurrents induce the secretion of transforming growth factor-beta-1 (TGF-β1) in fibroblasts and osteoblast-like cells. Interestingly, transcriptomic analysis uncovered that microcurrents enhance the transcriptional activation of genes implicated in Hedgehog, TGF-β1 and MAPK signaling pathways. Overall, our results demonstrate that microcurrents may enhance wound closure through a combination of signal transductions, via MAPK’s phosphorylation, and the transcriptional activation of specific genes involved in the healing process. These mechanisms should be further examined in vivo, in order to verify the beneficial effects of microcurrents in wound or fracture healing.
FGF2 Inhibits Early Pancreatic Lineage Specification during Differentiation of Human Embryonic Stem Cells
Authors: Dettmer Rabea , Cirksena Karsten , Münchhoff Julia , Kresse Jasmin , Diekmann Ulf , Niwolik Isabell , Buettner Falk F. R. , Naujok Ortwin
Published: August 2020

Growth factors are important regulators during organ development. For many vertebrates (but not humans) it is known how they contribute to the formation and expansion of PDX1-positive cells during pancreas organogenesis. Here, the effects of the fibroblast growth factors FGF2, FGF7, FGF10, and epidermal growth factor (EGF) on pancreas development in humans were assessed by using human pluripotent stem cells (hPSCs). During this, FGF2 was identified as a potent anti-pancreatic factor whereas FGF7, FGF10, and EGF increased the cell mass while retaining PDX1-positivity. FGF2 increased the expression of the anti-pancreatic factor sonic hedgehog (SHH) while suppressing PDX1 in a dose-dependent manner. Differentiating cells secreted SHH to the medium and we interrogated the cells’ secretome during differentiation to globally examine the composition of secreted signaling factors. Members of the TGF-beta-, Wnt-, and FGF-pathways were detected. FGF17 showed a suppressive anti-pancreatic effect comparable to FGF2. By inhibition of specific branches of FGF-receptor signaling, we allocated the SHH-induction by FGF2 to MEK/ERK-signaling and the anti-pancreatic effect of FGF2 to the receptor variant FGFR1c or 3c. Altogether, we report findings on the paracrine activity of differentiating hPSCs during generation of pancreatic progenitors. These observations suggest a different role for FGF2 in humans compared to animal models of pancreas organogenesis.
TonEBP Promotes β-Cell Survival under ER Stress by Enhancing Autophagy
Authors: Kang Hyun Je , Yoo Eun Jin , Lee Hwan Hee , An Seung Min , Park Hyun , Lee-Kwon Whaseon , Choi Soo Youn , Kwon Hyug Moo
Published: August 2020

The endoplasmic reticulum (ER) stress response and autophagy are important cellular responses that determine cell fate and whose dysregulation is implicated in the perturbation of homeostasis and diseases. Tonicity-responsive enhancer-binding protein (TonEBP, also called NFAT5) is a pleiotropic stress protein that mediates both protective and pathological cellular responses. Here, we examined the role of TonEBP in β-cell survival under ER stress. We found that TonEBP increases β-cell survival under ER stress by enhancing autophagy. The level of TonEBP protein increased under ER stress due to a reduction in its degradation via the ubiquitin–proteasome pathway. In response to ER stress, TonEBP increased autophagosome formations and suppressed the accumulation of protein aggregates and β-cell death. The Rel-homology domain of TonEBP interacted with FIP200, which is essential for the initiation of autophagy, and was required for autophagy and cell survival upon exposure to ER stress. Mice in which TonEBP was specifically deleted in pancreatic endocrine progenitor cells exhibited defective glucose homeostasis and a loss of islet mass. Taken together, these findings demonstrate that TonEBP protects against ER stress-induced β-cell death by enhancing autophagy.
Synthetic Notch-Receptor-Mediated Transmission of a Transient Signal into Permanent Information via CRISPR/Cas9-Based Genome Editing
Authors: Sgodda Malte , Alfken Susanne , Schambach Axel , Eggenschwiler Reto , Fidzinski Pawel , Hummel Michael , Cantz Tobias
Published: August 2020

Synthetic receptor biology and genome editing are emerging techniques, both of which are currently beginning to be used in preclinical and clinical applications. We were interested in whether a combination of these techniques approaches would allow for the generation of a novel type of reporter cell that would recognize transient cellular events through specifically designed synthetic receptors and would permanently store information about these events via associated gene editing. Reporting cells could be used in the future to detect alterations in the cellular microenvironment, including degenerative processes or malignant transformation into cancer cells. Here, we explored synthetic Notch (synNotch) receptors expressed in human embryonic kidney cells to investigate the efficacy of antigen recognition events in a time- and dose-dependent manner. First, we evaluated the most suitable conditions for synNotch expression based on dsRed-Express fluorophore expression. Then, we used a synNotch receptor coupled to transcriptional activators to induce the expression of a Cas9 nuclease targeted to a specific genomic DNA site. Our data demonstrate that recognition of various specific antigens via synNotch receptors robustly induced Cas9 expression and resulted in an indel formation frequency of 34.5%–45.5% at the targeted CXCR4 locus. These results provide proof of concept that reporter cells can be designed to recognize a given event and to store transient information permanently in their genomes.
Softening Behaviors of Severely Deformed Zn Alloy Studied by the Nanoindentation
Authors: Hu Jiangjiang , Sun Shuo , Zhang Wei , Peng Guangjian , Han Shuang , Sun Xu , Zhang Yusheng , Zhang Taihua
Published: August 2020

Zamak 3 alloy treatment by sliding-friction treatment (SFT) was investigated by nanoindentation to explore the influence of microstructure and strain rate on nanoscale deformation at room temperature. The results show that obvious material softening occurs in the ultrafine-grained (UFG) Zn alloy and strain-hardening happens in the twinning-deformed layer, respectively. It can be concluded that almost constant values of V in the UFG Zn alloy contribute to the dislocations moving along the grain boundary (GB) not cross the grain interior. In the twinning-deformed layer, the highly frequent dislocation–twinning boundary (TB) interactions are responsible for subsequent inverse Cottrell–Stokes at lower stress, which is quite different from dislocation–dislocation reaction inside the grain in their coarse-grained (CG) counterpart.
Novel Terahertz Nondestructive Method for Measuring the Thickness of Thin Oxide Scale Using Different Hybrid Machine Learning Models
Authors: Xu Zhou , Ye Dongdong , Chen Jianjun , Zhou Haiting
Published: August 2020

Effective control of the thickness of the hot-rolled oxide scale on the surface of the steel strip is very vital to ensure the surface quality of steel products. Hence, terahertz nondestructive technology was proposed to measure the thickness of thin oxide scale. The finite difference time domain (FDTD) numerical simulation method was employed to obtain the terahertz time-domain simulation data of oxide scale with various thickness (0–15 μm). Added Gaussian white noise with a Signal Nosie Reduction (SNR) of 10 dB was used when simulating real test signals, using four wavelet denoising methods to reduce noise and to compare their effectiveness. Two machine learning algorithms were adopted to set up models to achieve this goal, including the classical back-propagation (BP) neural network algorithm and the novel extreme learning machine (ELM) algorithm. The principal component analysis (PCA) algorithm and particle swarm optimization (PSO) algorithm were combined to reduce the dimensions of the terahertz time-domain data and improve the robustness of the machine learning model. It could be clearly seen that the novel hybrid PCA-PSO-ELM model possessed excellent prediction performance. Finally, this work proposed a novel, convenient, online, nondestructive, noncontact, safety and high-precision thin oxide scale thickness measuring method that could be employed to improve the surface quality of iron and steel products.
Bulk Cyclotron Resonance in the Topological Insulator Bi2Te3
Authors: Kamenskyi Dmytro L. , Pronin Artem V. , Benia Hadj M. , Martovitskii Victor P. , Pervakov Kirill S. , Selivanov Yurii G.
Published: August 2020

We investigated magneto-optical response of undoped Bi2Te3 films in the terahertz frequency range (0.3–5.1 THz, 10–170 cm−1) in magnetic fields up to 10 T. The optical transmission, measured in the Faraday geometry, is dominated by a broad Lorentzian-shaped mode, whose central frequency linearly increases with applied field. In zero field, the Lorentzian is centered at zero frequency, representing hence the free-carrier Drude response. We interpret the mode as a cyclotron resonance (CR) of free carriers in Bi2Te3. Because the mode’s frequency position follows a linear magnetic-field dependence and because undoped Bi2Te3 is known to possess appreciable number of bulk carriers, we associate the mode with a bulk CR. In addition, the cyclotron mass obtained from our measurements fits well the literature data on the bulk effective mass in Bi2Te3. Interestingly, the width of the CR mode demonstrates a behavior non-monotonous in field. We propose that the CR width is defined by two competing factors: impurity scattering, which rate decreases in increasing field, and electron-phonon scattering, which exhibits the opposite behavior.
Flow Stability, Convective Heat Transfer and Chemical Reactions in Ammonothermal Autoclaves—Insights by In Situ Measurements of Fluid Temperatures
Authors: Schimmel Saskia , Kobelt Ines , Heinlein Lukas , Kimmel Anna-Carina L. , Steigerwald Thomas G. , Schlücker Eberhard , Wellmann Peter
Published: August 2020

A variety of functional nitride materials, including the important wide bandgap semiconductor GaN, can be crystallized in exceptionally good structural quality by the ammonothermal method. However, the further development of this method is hindered by a lack of access to internal process parameters including fluid temperatures, flow stability and reaction kinetics. Internal temperature measurements are thus introduced as a tool for in situ monitoring of fluid flow stability in ammonothermal reactors as well as chemical reactions associated with enthalpy changes. The temperature change of an internal thermocouple is studied numerically in order to estimate possible errors due to heat conduction along thermocouples as well as due to their heat capacity. Results from otherwise identical experiments conducted with air at ambient pressure and ammonothermal reaction medium, respectively, are compared. The comparison indicates that internal temperature distributions during ammonothermal growth of GaN cannot be determined by measurements using ambient pressure air instead of supercritical ammonia. Even an approximate determination is not feasible, given that the internal temperature gradients differ by a factor of seven, and that the Grashof- and Rayleigh numbers differ by approximately four orders of magnitude. Most importantly, convective heat transfer by supercritical ammonia is found to greatly influence the temperature distribution inside the reaction chamber and its walls, suggesting that it probably needs to be taken into account in numerical simulations of the global thermal field of ammonothermal reactors.
The Sensitivity of the Pair-Angle Distribution Function to Protein Structure
Authors: Adams Patrick , Binns Jack , Greaves Tamar L. , Martin Andrew V.
Published: August 2020

The continued development of X-ray free-electron lasers and serial crystallography techniques has opened up new experimental frontiers. Nanoscale dynamical processes such as crystal growth can now be probed at unprecedented time and spatial resolutions. Pair-angle distribution function (PADF) analysis is a correlation-based technique that has the potential to extend the limits of current serial crystallography experiments, by relaxing the requirements for crystal order, size and number density per exposure. However, unlike traditional crystallographic methods, the PADF technique does not recover the electron density directly. Instead it encodes substantial information about local three-dimensional structure in the form of three- and four-body correlations. It is not yet known how protein structure maps into the many-body PADF correlations. In this paper, we explore the relationship between the PADF and protein conformation. We calculate correlations in reciprocal and real space for model systems exhibiting increasing degrees of order and secondary structural complexity, from disordered polypeptides, single alpha helices, helix bundles and finally a folded 100 kilodalton protein. These models systems inform us about the distinctive angular correlations generated by bonding, polypeptide chains, secondary structure and tertiary structure. They further indicate the potential to use angular correlations as a sensitive measure of conformation change that is complementary to existing structural analysis techniques.
Crenal Habitats: Sources of Water Mite (Acari: Hydrachnidia) Diversity
Authors: Pozojević Ivana , Pešić Vladimir , Goldschmidt Tom , Gottstein Sanja
Published: August 2020

Many studies emphasized the role that water mites play within the invertebrate communities of spring ecosystems, regarding species diversity and its significance within the crenal food web, as well as the specific preferences water mites exhibit towards spring typology. In pristine natural springs with permanent flow, water mites are nearly always present and usually display high diversity. This study aimed to determine whether significant differences in water mite assemblages between rheocrene (river-forming springs with dominant riffle habitats) and limnocrene (lake-forming springs with dominant pool habitats) karst springs could be detected in terms of species richness, diversity and abundance, but also in different ratios of specific synecological groups: crenobiont (exclusively found in springs), crenophilous (associated with springs) and stygophilous (associated with groundwater) water mite taxa. Our research was carried out on four limnocrenes and four rheocrenes in the Dinaric karst region of Croatia. Seasonal samples (20 sub-samples per sampling) were taken at each spring with a 200-µm net, taking into consideration all microhabitat types with coverage of at least 5%. Water mite abundance was found not to differ between morphological spring types. Significantly higher values of species richness and diversity indices were found in rheocrenes compared to limnocrenes, like those usually reported for this type of springs. However, unlike the studies previously reported, in this case, the higher shares of crenophilous and crenobiont water mite individuals were found in limnocrenes. The differences between stygophilous water mite taxa ratios among spring morphotypes were not statistically significant, indicating that the degree of the groundwater/surface water interaction (and water mite interaction therein) does not seem to be directly influenced by spring morphotype. Within this research, 40% of identified water mite species (eight out of twenty) were recorded for the first time in Croatia, thus highlighting again a huge gap in water mite knowledge of karst springs.
Diagnostic and Prognostic Indications of Nasopharyngeal Carcinoma
Authors: E. A. R. Engku Nur Syafirah , Irekeola Ahmad Adebayo , Yean Yean Chan
Published: August 2020

Nasopharyngeal carcinoma (NPC) is a disease that is highly associated with the latent infection of Epstein–Barr virus. The absence of obvious clinical signs at the early stage of the disease has made early diagnosis practically impossible, thereby promoting the establishment and progression of the disease. To enhance the stride for a reliable and less invasive tool for the diagnosis and prognosis of NPC, we synopsize biomarkers belonging to the two most implicated biological domains (oncogenes and tumor suppressors) in NPC disease. Since no single biomarker is sufficient for diagnosis and prognosis, coupled with the fact that the known established methods such as methylation-specific polymerase chain reaction (PCR), multiplex methylation-specific PCR, microarray assays, etc., can only accommodate a few biomarkers, we propose a 10-biomarker panel (KIT, LMP1, PIKC3A, miR-141, and miR-18a/b (oncogenic) and p16, RASSF1A, DAP-kinase, miR-9, and miR-26a (tumor suppressors)) based on their diagnostic and prognostic values. This marker set could be explored in a multilevel or single unified assay for the diagnosis and prognosis of NPC. If carefully harnessed and standardized, it is hoped that the proposed marker set would help transform the diagnostic and prognostic realm of NPC, and ultimately, help prevent the life-threatening late-stage NPC disease.
Design and Development of a Methodology Based on Expert Systems, Applied to the Treatment of Pressure Ulcers
Authors: Casal-Guisande Manuel , Comesaña-Campos Alberto , Cerqueiro-Pequeño Jorge , Bouza-Rodríguez José-Benito
Published: August 2020

The medical treatment of chronic wounds, pressure ulcers in particular, burdens healthcare systems nowadays with high expenses that result mainly from their monitoring and assessment stages. Decision support systems applied within the ‘remote medicine’ framework may be of help, not only to the process of monitoring the evolution of chronic wounds under treatment, but also to facilitate the prevention and early detection of potential risk conditions in the affected patients. In this paper, the design and definition of a new decision-support methodology to be applied to the monitoring and assessment stages of the medical treatment process for pressure ulcers is proposed. Built upon the use and development of expert systems, the methodology makes it possible to generate alerts derived from the evolution of a patient’s chronic wound, by means of the interpretation and combination of data coming from both an image of the wound, and the considerations of a healthcare professional with expertise in the subject matter. Some positive results are already shown regarding the determination of the ulcer’s status in the tests that have been carried out so far. Therefore, it is considered that the proposed methodology might lead to substantial improvements regarding both the treatment’s efficiency and cost savings.
Educational Escape Rooms as a Tool for Horizontal Mathematization: Learning Process Evidence
Authors: Piñero Charlo José Carlos
Published: August 2020

The curricular perspective based on teaching processes which takes formal mathematical knowledge as a starting point has been severely criticized. This traditional perspective considers that the formal mathematical knowledge has to be taught prior to the application so, once taught, it can be used to solve problems. Along with this criticism, curricular alternative proposals that have focused attention on the learning process (rather than in the teaching one) have been developed. Recently, game-based learning has been developed as a problem-based learning methodology, able to achieve a deeper implication of the students. In line with this approach, the main scope of this paper is to provide evidence of the learning process in game-based learning environments. To do this, student teachers have designed an educational escape room that fits curricular learning outcomes. This manuscript reports on an educational escape room experience that was implemented in three different Primary Education Schools (total student population of 117 students, while here we present a fragment of 5 participants). In order to evaluate the development of certain knowledge, a transcribed fragment is presented and analyzed. In the reported experience, evidence of learning processes and horizontal mathematization are reported in the frame of an educational escape room. This constitutes an evidence of learning processes in gamified environments.
On Teaching Programming Fundamentals and Computational Thinking with Educational Robotics: A Didactic Experience with Pre-Service Teachers
Authors: Piedade João , Dorotea Nuno , Pedro Ana , Matos João Filipe
Published: August 2020

This study aims to analyze how pre-service informatics teachers design learning scenarios with robotics to teach programming fundamentals and to promote computational thinking skills. A descriptive and exploratory case study design was implemented with 26 pre-service informatics teachers. Data were collected from the participants using qualitative and quantitative instruments. The main results pointed out the affordances and possibilities of the use of learning scenarios with robotics to teach programming fundamentals and to promote computational thinking skills as well as a strong path to promote the application of contents of the other Science, Technology, Engineering, Arts and Mathematics (STEAM) areas. Another significant finding was the impact of the didactic experience on the level of interest and self-confidence of the pre-service teachers in using robotics for teaching purposes. The results showed the importance of these didactics experiences to the pre-service teachers preparation and to apply the pedagogic approaches they have learned in theory in practical activities and to transfer this knowledge to new pedagogical situations and problems.
Measurement of the MOOC Phenomenon by Pre-Service Teachers: A Descriptive Case Study
Authors: Gómez-Galán José , Lázaro-Pérez Cristina , Martínez-López José Ángel , López-Meneses Eloy
Published: August 2020

The main objective of this research is to establish the measurement of pre-service teachers on the MOOC phenomenon, one of the most important manifestations within the processes of on-line education that have emerged under the protection of the digital paradigm. The research methodology used was of an exploratory, qualitative, and descriptive nature. It falls within the generic scope of qualitative research methods of an ethnographic nature through the analysis of learning objects and interventions in the network. The sample (n = 218) was composed of students from the educational field, who took a subject focused on ICT applied to education, over several academic years. Using the edublog as a digital and documentary source, a total of 1962 frequencies were collected referring to the advantages (1052 frequencies) and limitations (910 frequencies) that they determined when carrying out these courses. As main results, it is worth mentioning that pre-service teachers consider MOOC courses valuable as teaching models in socio-educational contexts. They offer unquestionable advantages such as free of charge usage, training for disadvantaged groups, flexible hours, etc. However, their disadvantages are also important. For example, it is considered that these courses do not adequately follow up on the student, that the materials they offer are not very innovative, or also that the evaluation of the learning is inadequate. It is interesting to note that the main problems identified are of a pedagogical, not technical, nature.
Characteristics of Academic Adaptation and Subjective Well-Being in University Students with Chronic Diseases
Authors: Shamionov Rail M. , Grigoryeva Marina V. , Grinina Elena S. , Sozonnik Aleksey V.
Published: August 2020

Studying academic adaptation and subjective well-being in students with chronic diseases can help to explain psychological compensatory mechanisms and help with the development of socio-psychological support programs. It is supposed that the defining role is played by general adaptive potential, and the presence of chronic diseases results in variations in academic adaptation, which, alongside other variables, acts as a predictor of subjective well-being and satisfaction of basic needs. The sample consisted of first-year university students aged 17–26 years (mean = 19.6, SD = 2.8, 18.4% male; n = 419 persons, of which 34.8% with chronic diseases of various etiologies). To evaluate the components of students’ academic adaptation, we used the Academic Adaptation Scale; general adaptive potential was measured using the Multilevel Personal Adaptability Questionnaire; to evaluate subjective well-being, we used the Subjective Well-Being Scale; and satisfaction using the Life Scale. Satisfaction of basic needs was defined with the Basic Needs Satisfaction in General Scale. Students with chronic diseases demonstrated lower manifested adaptive potential, general markers of academic adaptation, subjective well-being, and satisfaction of basic psychological needs. The results showed that interrelations between various markers in students are largely mediated by academic adaptation and adaptive potential. Thus, the interconnection between adaptive potential and satisfaction of basic needs is significantly mediated by students’ academic adaptation, whereas the interconnection between chronic diseases and academic adaptation is mediated by adaptive potential. In other words, the findings support the assumption regarding the significant mediating role of these variables in subjective well-being. Cognitive, motivational, and communicative components of academic adaptation can serve as compensatory factors for experiencing subjective well-being in students with chronic diseases.
Prospective Efficient Ambient Energy Harvesting Sources for IoT-Equipped Sensor Applications
Authors: Mishu Mahmuda Khatun , Rokonuzzaman Md. , Pasupuleti Jagadeesh , Shakeri Mohammad , Rahman Kazi Sajedur , Hamid Fazrena Azlee , Tiong Sieh Kiong , Amin Nowshad
Published: August 2020

In the past few years, the internet of things (IoT) has garnered a lot of attention owing to its significant deployment for fulfilling the global demand. It has been seen that power-efficient devices such as sensors and IoT play a significant role in our regular lives. However, the popularity of IoT sensors and low-power electronic devices is limited due to the lower lifetime of various energy resources which are needed for powering the sensors over time. For overcoming this issue, it is important to design and develop better, high-performing, and effective energy harvesting systems. In this article, different types of ambient energy harvesting systems which can power IoT-enabled sensors, as well as wireless sensor networks (WSNs), are reviewed. Various energy harvesting models which can increase the sustainability of the energy supply required for IoT devices are also discussed. Furthermore, the challenges which need to be overcome to make IoT-enabled sensors more durable, reliable, energy-efficient, and economical are identified.
An Agent-Based Approach to Realize Emergent Configurations in the Internet of Things
Authors: Alkhabbas Fahed , Spalazzese Romina , Davidsson Paul
Published: August 2020

The Internet of Things (IoT) has enabled physical objects and devices, often referred to as things, to connect and communicate. This has opened up for the development of novel types of services that improve the quality of our daily lives. The dynamicity and uncertainty of IoT environments, including the mobility of users and devices, make it hard to foresee at design time available things and services. Further, users should be able to achieve their goals seamlessly in arbitrary environments. To address these challenges, we exploit Artificial Intelligence (AI) to engineer smart IoT systems that can achieve user goals and cope with the dynamicity and uncertainty of their environments. More specifically, the main contribution of this paper is an approach that leverages the notion of Belief-Desire-Intention agents and Machine Learning (ML) techniques to realize Emergent Configurations (ECs) in the IoT. An EC is an IoT system composed of a dynamic set of things that connect and cooperate temporarily to achieve a user goal. The approach enables the distributed formation, enactment, adaptation of ECs, and conflict resolution among them. We present a conceptual model of the entities of the approach, its underlying processes, and the guidelines for using it. Moreover, we report about the simulations conducted to validate the feasibility of the approach and evaluate its scalability.
Framework of IoT Services over Unidirectional Visible Lights Communication Networks
Authors: Kim So-Yong , Kim Cheol-Min , Koh Seok-Joo
Published: August 2020

Visible Light Communication (VLC) has been noted as an emerging technology for communications in wireless local area networks. VLC provides some distinctive features over the conventional wireless access technologies, such as Wi-Fi, Bluetooth, or ZigBee. The most prominent feature of VLC is that it can provide more exact location information, since it is based on a particular light. In addition, VLC can reduce the frequency interferences from numerous wireless channels, since it uses a completely different radio frequency channel from the conventional wireless access technologies. Thus, VLC can be used for Internet-of-Things (IoT) services. Nevertheless, up to now, not enough studies on how to provide IoT services over VLC networks have been conducted. In this paper, we propose a framework to provide IoT services in VLC networks. In particular, we will consider the unidirectional VLC network, in which the downlink channel from the VLC transmitter to the VLC receiver is given by using VLC communication, whereas the uplink channel from the VLC receiver to the VLC transmitter is implemented by using another wireless access technology, such as Wi-Fi. This is because most of the VLC receivers, such as mobile phones, cannot support the uplink VLC communication. Based on the framework of IoT services over unidirectional VLC, in this paper, we also propose the VLC–IoT protocol (VIP) which is an application layer protocol for data transport with the session management functionality that can be used to effectively provide IoT services among IoT servers, VLC transmitters and VLC receivers in the networks. The proposed VIP protocol is implemented by using the Cooja simulator. For performance analysis, the proposed scheme is compared with the existing CoAP-based scheme that does not provide the session management. From a variety of simulation experiments, we see that the proposed scheme can provide lower data transmission and handover delays, compared to the existing scheme.
Numerical Analysis and Preliminary Experiment of a Solar Assisted Heat Pump Drying System for Chinese Wolfberry
Authors: Hu Zhongting , Zhang Sheng , Chu Wenfeng , He Wei , Yu Cairui , Yu Hancheng
Published: August 2020

The present work investigated a solar assisted heat pump system for drying Chinese wolfberry. The kinetic characteristic was firstly analyzed through a series of lab experiments. It was concluded that the Page model was the most suitable for predicting the heat and mass transfer of the wolfberry. Based on the wolfberry kinetic model, solar collector model and chamber air model, the coupled drying system model was developed. The accuracy of the mathematic model was determined through comparing with the preliminary experimental results. The influence of operating conditions on the thermal and energy performance of the dryer for the different operating mode was discussed. The drying weight of no more than 75 kg may be preferable in the stand-alone solar drying mode, and less than 15 h was needed to be dried. The electric energy consumption in the solar assisted the heat pump drying mode was lower than that in the stand-alone heat pump mode, and it was recommended that about 50 kg of wolfberry to be dried in the solar assisted heat pump system. Compared to the autumn drying, the reduction in the electric energy consumption was around 9.1 kWh during the 11 h summer drying process. The obtained results demonstrated the feasibility of the combined system for drying wolfberry, and also can provide the basic theoretical and experimental data support for the following research.