bluuebunny/crossref_metadata_2025 huggingface dataset:
Personalized Approach to the Role of Endoscopic Ultrasound in the Diagnosis and Management of Pancreaticobiliary Malignancies
Authors: Makar Michael , Zhao Eric , Tyberg Amy
Published: March 2021

Pancreaticobiliary malignancies arise from different areas within the pancreas and biliary tree. Endoscopic ultrasound (EUS) is a well-recognized diagnostic and therapeutic modality in the treatment of pancreaticobiliary diseases, and more specifically, pancreaticobiliary malignancies. Traditionally used for diagnostic purposes, EUS plays a critical role in tissue sampling and cancer staging. The emergence of the new field of interventional EUS has allowed EUS to also play a critical role in therapeutic management. Novel interventional EUS procedures such as EUS-guided gastrojejunostomy (EUS-GE), EUS-guided biliary drainage (EUS-BD), and EUS-guided gallbladder drainage (EUS-GLB) can be utilized to treat complications of pancreaticobiliary malignancies such as gastric outlet obstruction, obstructive jaundice, and cholecystitis. In addition, interventional EUS procedures can be utilized for the palliation of unresectable malignancies both for source control with EUS-radiofrequency ablation (EUS-RFA) and for the treatment of abdominal pain refractory to opioid medications with EUS-guided celiac axis neurolysis. However, patient selection remains a critical component in both diagnostic and therapeutic interventions and must be tailored to individual patient wishes, disease pathology, and overall prognosis.
Relationship between the miRNA Profiles and Oncogene Mutations in Non-Smoker Lung Cancer. Relevance for Lung Cancer Personalized Screenings and Treatments
Authors: Izzotti Alberto , Coronel Vargas Gabriela , Pulliero Alessandra , Coco Simona , Vanni Irene , Colarossi Cristina , Blanco Giuseppina , Agodi Antonella , Barchitta Martina , Maugeri Andrea ,   CT-ME-EN Cancer Registry Workers, Oliveri Conti Gea , Ferrante Margherita , Sciacca Salvatore
Published: March 2021

Oncogene mutations may be drivers of the carcinogenesis process. MicroRNA (miRNA) alterations may be adaptive or pathogenic and can have consequences only when mutation in the controlled oncogenes occurs. The aim of this research was to analyze the interplay between miRNA expression and oncogene mutation. A total of 2549 miRNAs were analyzed in cancer tissue—in surrounding normal lung tissue collected from 64 non-smoking patients and in blood plasma. Mutations in 92 hotspots of 22 oncogenes were tested in the lung cancer tissue. MicroRNA alterations were related to the mutations occurring in cancer patients. Conversely, the frequency of mutation occurrence was variable and spanned from the k-ras and p53 mutation detected in 30% of patients to 20% of patients in which no mutation was detected. The prediction of survival at a 3-year follow up did not occur for mutation analysis but was, conversely, well evident for miRNA analysis highlighting a pattern of miRNA distinguishing between survivors and death in patients 3 years before this clinical onset. A signature of six lung cancer specific miRNAs occurring both in the lungs and blood was identified. The obtained results provide evidence that the analysis of both miRNA and oncogene mutations was more informative than the oncogene mutation analysis currently performed in clinical practice.
Maternal Psychological and Biological Factors Associated to Gestational Complications
Authors: Ramiro-Cortijo David , de la Calle Maria , Benitez Vanesa , Gila-Diaz Andrea , Moreno-Jiménez Bernardo , Arribas Silvia M. , Garrosa Eva
Published: March 2021

Early detection of gestational complications is a priority in obstetrics. In our social context, this is linked to maternity age. Most studies are focused on biological factors. However, pregnancy is also influenced by social and psychological factors, which have not been deeply explored. We aimed to identify biopsychosocial risk and protective factors associated with the development of maternal and fetal complications. We enrolled 182 healthy pregnant women, and plasma melatonin and cortisol levels were measured in the first trimester by chemiluminescent immunoassays. At different time points along gestation, women answered several questionnaires (positive and negative affect schedule, hospital anxiety and depression scale, pregnancy concerns scale, life orientation test, resilience scale, life satisfaction scale and life–work conflicts scale). They were followed up until delivery and categorized as normal pregnancy, maternal or fetal complications. Maternal complications were associated with low melatonin (OR = 0.99 [0.98; 1.00]; p-value = 0.08) and life satisfaction (OR = 0.64 [0.41; 0.93]; p-value = 0.03) and fetal complications were associated with high cortisol (OR = 1.06 [1.02; 1.13]; p-value = 0.04), anxiety (OR = 2.21 [1.10; 4.55]; p-value = 0.03) and life–work conflicts (OR = 1.92 [1.04; 3.75]; p-value = 0.05). We conclude that psychological factors influence pregnancy outcomes in association with melatonin and cortisol alterations. High maternal melatonin and life satisfaction levels could be potential protective factors against the development of maternal complications during pregnancy. Low anxiety and cortisol levels and reduced work–life conflicts could prevent fetal complications.
Prognostic Factors for Radiographic Progression in Patients with Seronegative Rheumatoid Arthritis
Authors: Park Eun-Jung , Jeong WooSeong , Kim Jinseok
Published: March 2021

(1) Background: It has long been suggested that seronegative rheumatoid arthritis (RA) represents a clinical entity quite distinct from that of seropositive. However, analytical studies of seronegative RA dedicated to clinical outcomes regarding radiographic progression and related risk factors are scarce. The aim of this study is to evaluate radiographic outcome and prognostic factors for radiographic progression in patients with seronegative rheumatoid arthritis. (2) Methods: Subjects included RA patients reported as seronegative for both rheumatoid factor and anti-citrullinated protein antibody, who were treated at Jeju National University Hospital in South Korea between 2003 and 2016, including follow-up of at least 2 years. All patients fulfilled 1987 ACA or 2010 ACR/EULAR RA criteria. Radiographic progression was measured by yearly change in the Sharp van der Heijde (SvdH) score during follow-up periods. Medical records, laboratory and radiographic data were retrospectively analyzed, and linear regression analysis was performed to evaluate prognostic factors for radiographic progression in patients with seronegative rheumatoid arthritis. (3) Results: In total, 116 patients with seronegative RA were observed and 43 (37.1%) patients demonstrated radiographic damage during follow-up period. Mean age at diagnosis was 48 years and 86 (74.1%) patients were female. Symptom duration at diagnosis was 1.3 years and mean follow-up duration was 5.2 years. Patients with radiographic damage at diagnosis were 14 (12.1%) and mean SvdH score was 6.8 at diagnosis. Radiographic damage and SvdH at diagnosis significantly correlated with radiographic progression in patients with seronegative RA after adjusting age, sex, symptom duration, number of active synovitis, and CRP at diagnosis (β-coefficient 6.5 ± 1.84; p = 0.001 and β-coefficient 0.12 ± 0.02; p < 0.001, respectively). (4) Conclusions: This study determined that radiographic damage and SvdH at diagnosis were predictive factors in progression of radiographic damage in patients with seronegative rheumatoid arthritis. A large comparative study dedicated to this issue in seronegative RA is required.
Performance Management for Growth: A Framework Based on EVA
Authors: Tudose Mihaela Brindusa , Rusu Valentina Diana , Avasilcai Silvia
Published: March 2021

Some of the constructs in the field of performance management are intuitive or not empirically validated. This study provides a data-driven framework for measuring and improving the performance through synchronized strategies. The ultimate goal was to provide support for increasing business performance. Empirical research materializes in an exploratory case study and a statistical analysis with econometric models. The case study revealed that a company can improve its performance, even in periods of growth, being characterized by consistent investments. The statistical analysis, performed on a restricted sample of companies, confirmed the results that were provided by the case study. The measurement of performance was made by capitalizing on financial and non-financial data precisely to intensify the interest for corporate sustainability. The obtained results, contrary to previous research that showed that economic value added (EVA) is negatively influenced by the increase in invested capital, open up new research perspectives to find out whether, at the industry level, performance appraisal that is based on EVA stimulates the development of a business’s economic capital. The research has a double utility: scientific (by providing an overview of the state of the art in the field of performance management) and practical (by providing a reference model for measuring and monitoring performance).
Foreign Direct Investment and World Pandemic Uncertainty Index: Do Health Pandemics Matter?
Authors: Ho Linh Tu , Gan Christopher
Published: March 2021

This paper explores the impacts of health pandemics on foreign direct investment (FDI) using the new world pandemic uncertainty index (WPUI). We investigate the effects of pandemics, including COVID-19, on FDI based on a sample of 142 economies and sub-samples (incomes and regions) from 1996 to 2019. The two-step system Generalised Method of Moments estimation of linear dynamic panel-data model (DPDGMM) is used in this study. The estimation results are robust with the results of the two-step sequential (two-stage) estimation of linear panel-data models (SELPDM) and the two-step system Generalised Method of Moments estimation (BBGMM). The results show that health pandemics have negative impacts on FDI. Significantly, the uncertainty caused by pandemics creates adverse shocks on FDI net inflows in Asia-Pacific countries and emerging economies.
Typological Shift in Bilinguals’ L1: Word Order and Case Marking in Two Varieties of Child Quechua
Authors: Kalt Susan E. , Geary Jonathan A.
Published: March 2021

We compare speech production and find morphosyntactic change among children and adolescents speaking two closely related varieties of Quechua in Cuzco, Peru, and Chuquisaca, Bolivia. Quechua languages traditionally employ Object-Verb (OV) word order in main clauses, but robust case marking permits other orders, especially to focalize new information through constituent fronting. In Chuquisaca, but not Cuzco, we find that schoolchildren often omit the accusative suffix -ta from direct objects while retaining a prosodic trace of -ta. In other varieties, loss of accusative marking is associated with a shift towards Verb-Object (VO) word order, as in Spanish. However, we find that Chuquisaqueños use more canonical OV and possessor-possessed order in declarative sentences than do Cuzqueños, who employ a wide range of word orders at the sentence level and deviate from the possessor-possessed norm for Quechua noun phrases. Our finding of more rigid word order in Chuquisaca highlights the complex factors contributing to typological shift in word order and morphology: Omission of case morphology places a greater burden on word order to identify grammatical roles. Further, we find that Chuquisaqueño schoolchildren alone have begun to use huk, “one,” to mark indefiniteness, perhaps to replace determiner-like functions ascribed to -ta and to obsolescent markers such as evidentials.
Long-Term Survival and Value of 18F-FDG PET/CT in Patients with Gastroenteropancreatic Neuroendocrine Tumors Treated with Second Peptide Receptor Radionuclide Therapy Course with 177Lu-DOTATATE
Authors: Rodrigues Margarida , Winkler Kevin-Klaus , Svirydenka Hanna , Nilica Bernhard , Uprimny Christian , Virgolini Irene
Published: March 2021

Peptide receptor radionuclide therapy (PRRT) has been recognized as a promising therapy against neuroendocrine tumors (NETs). The use of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in NETs has been a matter of controversy. The purpose of this study was to evaluate the long-term survival and efficacy of a second PRRT course with 177Lu-DOTATE in patients with advanced gastroenteropancreatic (GEP) NETs. Furthermore, the value of 18F-FDG PET/CT in these patients was evaluated. 40 patients with GEP NETs who underwent two PRRT courses with 177Lu-DOTATATE and combined examinations with 68Ga-DOTA-TOC and 18F-FDG PET/CT were evaluated. After the second PRRT course, two patients (5.0%) were in partial remission, 21 patients (52.5%) in stable disease and 17 patients (42.5%) had progressive disease. The median overall survival was 122.10 months. After the second PRRT course, the median overall survival was significantly higher (p = 0.033) in the 18F-FDG-negative group compared to the 18F-FDG-positive group (145.50 versus 95.06 months, respectively). The median time to progression was 19.37 months. In conclusion, a second PRRT course with 177Lu-DOTATE is an effective treatment approach for GEP NET patients with disease progression. A change in 18F-FDG status after PRRT may predict the disease course and survival. Patients who are 18F-FDG-negative have a significantly longer overall survival than those who are 18F-FDG-positive.
Hybrid Nanofluid Flow over a Permeable Non-Isothermal Shrinking Surface
Authors: Waini Iskandar , Ishak Anuar , Pop Ioan
Published: March 2021

In this paper, we examine the influence of hybrid nanoparticles on flow and heat transfer over a permeable non-isothermal shrinking surface and we also consider the radiation and the magnetohydrodynamic (MHD) effects. A hybrid nanofluid consists of copper (Cu) and alumina (Al2O3) nanoparticles which are added into water to form Cu-Al2O3/water. The similarity equations are obtained using a similarity transformation and numerical results are obtained via bvp4c in MATLAB. The results show that dual solutions are dependent on the suction strength of the shrinking surface; in addition, the heat transfer rate is intensified with an increase in the magnetic parameter and the hybrid nanoparticles volume fractions for higher values of the radiation parameter. Furthermore, the heat transfer rate is higher for isothermal surfaces as compared with non-isothermal surfaces. Further analysis proves that the first solution is physically reliable and stable.
Empirical Convergence Theory of Harmony Search Algorithm for Box-Constrained Discrete Optimization of Convex Function
Authors: Yoon Jin Hee , Geem Zong Woo
Published: March 2021

The harmony search (HS) algorithm is an evolutionary computation technique, which was inspired by music improvisation. So far, it has been applied to various scientific and engineering optimization problems including project scheduling, structural design, energy system operation, car lane detection, ecological conservation, model parameter calibration, portfolio management, banking fraud detection, law enforcement, disease spread modeling, cancer detection, astronomical observation, music composition, fine art appreciation, and sudoku puzzle solving. While there are many application-oriented papers, only few papers exist on how HS performs for finding optimal solutions. Thus, this preliminary study proposes a new approach to show how HS converges on an optimal solution under specific conditions. Here, we introduce a distance concept and prove the convergence based on the empirical probability. Moreover, a numerical example is provided to easily explain the theorem.
Correlations between Retinal Arterial Morphometric Parameters and Neurodegeneration in Patients with Type 2 Diabetes Mellitus with No or Mild Diabetic Retinopathy
Authors: Damian Ioana , Nicoară Simona Delia
Published: March 2021

Background and Objectives: In patients with diabetes mellitus (DM), the neural retina is starting to degenerate before the development of vascular lesions. Our purpose was to investigate the correlation between the retinal arterial morphometric parameters and structural neurodegeneration in patients with type 2 DM with no or mild diabetic retinopathy (DR). Materials and Methods: This is a prospective study including 53 eyes of patients with type 2 DM and 32 eyes of healthy controls. Based on SD-OCT (spectral domain—optical coherence tomography) images, using a micro-densitometry method, we measured the outer and luminal diameter of retinal arteries and calculated the AWT (arterial wall thickness), WLR (wall-to-lumen ratio), and WCSA (wall cross-sectional area). GCL (ganglion cell layer) and RNFL (retinal nerve fiber layer) thickness were analyzed in correlation with the retinal arterial morphometric parameters mentioned above. Results: GCL was thinner in the inner quadrants in the NDR (no DR) group compared to controls (p < 0.05). RAOD (retinal artery outer diameter), RALD (retinal artery lumen diameter), AWT, WLR, and WCSA were similar between groups. A regression model considering age, gender, duration of DM, and HbA1C was carried out. Central GCL thickness was correlated positively with RAOD (coefficient 0.360 per µm, p = 0.011), RALD (coefficient 0.283 per µm, p = 0.050), AWT (coefficient 0.304 per µm, p = 0.029), and WCSA (coefficient 3.90 per µm, p = 0.005). Duration of DM was positively correlated with WCSA (coefficient 0.311 per one year duration of diabetes, p = 0.043). Conclusions: Significant GCL thinning in the inner quadrants preceded the morphological retinal arterial morphometric changes, supporting the neurodegeneration as primary pathogenic mechanism in DR.
Effect of the Fe2O3 Addition Amount on Dephosphorization of Hot Metal with Low Basicity Slag by High-Temperature Laboratorial Experiments
Authors: Yang Wenkui , Yang Jian , Shi Yanqiu , Yang Zhijun , Gao Fubin , Zhang Runhao , Sun Han
Published: March 2021

In this paper, the influence of the Fe2O3 addition amount on the dephosphorization of hot metal at 1623 K with the slag of the low basicity (CaO/SiO2) of about 1.5 was investigated by using high-temperature laboratorial experiments. With increasing the Fe2O3 addition amount from 5 to 30 g, the contents of [C], [Si], [Mn] and [P] in the hot metal at the end of dephosphorization are decreased and the corresponding removal ratios increase. In dephosphorization slags, the phosphorus mainly exists in the form of the nCa2SiO4–Ca3(PO4)2 solid solution in the phosphorus-rich phase and the value of coefficient n decreases from 20 to 1. Furthermore, the oxygen potential and activity at the interface between the slag and hot metal are increased. When the oxygen potential and the oxygen activity at the interface are greater than 0.72 × 10−12 and 7.1 × 10−3, respectively, the dephosphorization ratio begins to increase rapidly. When the Fe2O3 addition amount is increased to 30 g, the ratio of the Fe2O3 addition amount to theoretical calculation consumption is around 175%, and the dephosphorization ratio reaches the highest value of 83.3%.
Creating an Artificial 3-Dimensional Ovarian Follicle Culture System Using a Microfluidic System
Authors: Healy Mae W. , Dolitsky Shelley N. , Villancio-Wolter Maria , Raghavan Meera , Tillman Alexandra R. , Morgan Nicole Y. , DeCherney Alan H. , Park Solji , Wolff Erin F.
Published: March 2021

We hypothesized that the creation of a 3-dimensional ovarian follicle, with embedded granulosa and theca cells, would better mimic the environment necessary to support early oocytes, both structurally and hormonally. Using a microfluidic system with controlled flow rates, 3-dimensional two-layer (core and shell) capsules were created. The core consists of murine granulosa cells in 0.8 mg/mL collagen + 0.05% alginate, while the shell is composed of murine theca cells suspended in 2% alginate. Somatic cell viability tests and hormonal assessments (estradiol, progesterone, and androstenedione) were performed on days 1, 6, 13, 20, and 27. Confocal microscopy confirmed appropriate compartmentalization of fluorescently-labeled murine granulosa cells to the inner capsule and theca cells to the outer shell. Greater than 78% of cells present in capsules were alive up to 27 days after collection. Artificially constructed ovarian follicles exhibited intact endocrine function as evidenced by the production of estradiol, progesterone, and androstenedione. Oocytes from primary and early secondary follicles were successfully encapsulated, which maintained size and cellular compartmentalization. This novel microfluidic system successfully encapsulated oocytes from primary and secondary follicles, recapitulating the two-compartment system necessary for the development of the mammalian oocyte. Importantly, this microfluidic system can be easily adapted for sterile, high throughput applications.
Laser Grinding of Single-Crystal Silicon Wafer for Surface Finishing and Electrical Properties
Authors: Li Xinxin , Wang Yimeng , Guan Yingchun
Published: March 2021

In this paper, we first report the laser grinding method for a single-crystal silicon wafer machined by diamond sawing. 3D laser scanning confocal microscope (LSCM), X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), laser micro-Raman spectroscopy were utilized to characterize the surface quality of laser-grinded Si. Results show that SiO2 layer derived from mechanical machining process has been efficiently removed after laser grinding. Surface roughness Ra has been reduced from original 400 nm to 75 nm. No obvious damages such as micro-cracks or micro-holes have been observed at the laser-grinded surface. In addition, laser grinding causes little effect on the resistivity of single-crystal silicon wafer. The insights obtained in this study provide a facile method for laser grinding silicon wafer to realize highly efficient grinding on demand.
Epidemiology of Mucormycosis in India
Authors: Prakash Hariprasath , Chakrabarti Arunaloke
Published: March 2021

Mucormycosis is an angioinvasive disease caused by saprophytic fungi of the order Mucorales. The exact incidence of mucormycosis in India is unknown due to the lack of population-based studies. The estimated prevalence of mucormycosis is around 70 times higher in India than that in global data. Diabetes mellitus is the most common risk factor, followed by haematological malignancy and solid-organ transplant. Patients with postpulmonary tuberculosis and chronic kidney disease are at additional risk of developing mucormycosis in this country. Trauma is a risk factor for cutaneous mucormycosis. Isolated renal mucormycosis in an immunocompetent host is a unique entity in India. Though Rhizopus arrhizus is the most common etiological agent of mucormycosis in this country, infections due to Rhizopus microsporus, Rhizopus homothallicus, and Apophysomyces variabilis are rising. Occasionally, Saksenaea erythrospora, Mucor irregularis, and Thamnostylum lucknowense are isolated. Though awareness of the disease has increased among treating physicians, disease-associated morbidity and mortality are still high, as patients seek medical attention late in the disease process and given the low affordability for therapy. In conclusion, the rise in the number of cases, the emergence of new risk factors and causative agents, and the challenges in managing the disease are important concerns with mucormycosis in India.
Biases in Viral Metagenomics-Based Detection, Cataloguing and Quantification of Bacteriophage Genomes in Human Faeces, a Review
Authors: Callanan Julie , Stockdale Stephen R. , Shkoporov Andrey , Draper Lorraine A. , Ross R. Paul , Hill Colin
Published: March 2021

The human gut is colonised by a vast array of microbes that include bacteria, viruses, fungi, and archaea. While interest in these microbial entities has largely focused on the bacterial constituents, recently the viral component has attracted more attention. Metagenomic advances, compared to classical isolation procedures, have greatly enhanced our understanding of the composition, diversity, and function of viruses in the human microbiome (virome). We highlight that viral extraction methodologies are crucial in terms of identifying and characterising communities of viruses infecting eukaryotes and bacteria. Different viral extraction protocols, including those used in some of the most significant human virome publications to date, have introduced biases affecting their a overall conclusions. It is important that protocol variations should be clearly highlighted across studies, with the ultimate goal of identifying and acknowledging biases associated with different protocols and, perhaps, the generation of an unbiased and standardised method for examining this portion of the human microbiome.
Multiscale Microbial Preservation and Biogeochemical Signals in a Modern Hot-Spring Siliceous Sinter Rich in CO2 Emissions, Krýsuvík Geothermal Field, Iceland
Authors: Álvaro Jose Javier , Sánchez-Román Mónica , Nierop Klaas G.J. , Peterse Francien
Published: March 2021

The microbial communities inferred in silica sinter rocks, based on multiscale morphological features (fabrics and textures) and the presence of lipid biomarkers and their carbon isotopic composition, are evaluated in the Krýsuvík geothermal area of Iceland. Close to vent environments (T > 75 °C and pH 1.7‒3), stream floors are capped with homogeneous vitreous crusts and breccia levels, with no distinct recognizable silicified microbes. About 4 m far from the vents (T 75‒60 °C and pH 3‒6) and beyond (T < 60 °C and pH 6‒7.6), microbial sinters, including wavy and palisade laminated and bubble fabrics, differ between abandoned meanders and desiccated ponds. Fabric and texture variances are related to changes in the ratio of filament/coccoid silicified microbes and associated porosity. Coatings of epicellular silica, less than 2 µm thick, favor identification of individual microbial filaments, whereas coalescence of opal spheres into agglomerates precludes recognition of original microbial textures and silicified microbes. Episodic fluctuations in the physico-chemical conditions of surface waters controlled the acidic hydrolysis of biomarkers. Wavy laminated fabrics from pond margins comprise fatty acids, mono- and dialkyl glycerol, mono- and diethers, monoalkyl glycerol esters and small traces of 10-methyl branched C16 and C18 fatty acids and archaeol, indicative of intergrowths of cyanobacteria, Aquificales, and sulfate reducing bacteria and methanogenic archaea. In contrast, wavy laminated fabrics from abandoned meanders and palisade laminated fabrics from ponds differ in their branched fatty acids and the presence vs. absence of bacteriohopanetetrol, reflecting different cyanobacterial contributions. δ13C values of biomarkers range from −22.7 to −32.9‰, but their values in the wavy (pond) and bubble fabrics have much wider ranges than those of the wavy (meander), palisade, and vitreous fabrics, reflecting dissolved inorganic carbon (DIC) sources and a decrease in 13C downstream outflow channels, with heavier values closer to vents and depleted values in ponds.
Exploration for Platinum-Group Minerals in Till: A New Approach to the Recovery, Counting, Mineral Identification and Chemical Characterization
Authors: Makvandi Sheida , Pagé Philippe , Tremblay Jonathan , Girard Réjean
Published: March 2021

The discovery of new mineral deposits contributes to the sustainable mineral industrial development, which is essential to satisfy global resource demands. The exploration for new mineral resources is challenging in Canada since its vast lands are mostly covered by a thick layer of Quaternary sediments that obscure bedrock geology. In the course of the recent decades, indicator minerals recovered from till heavy mineral concentrates have been effectively used to prospect for a broad range of mineral deposits including diamond, gold, and base metals. However, these methods traditionally focus on (visual) investigation of the 0.25–2.0 mm grain-size fraction of unconsolidated sediments, whilst our observations emphasize on higher abundance, or sometimes unique occurrence of precious metal (Au, Ag, and platinum-group elements) minerals in the finer-grained fractions (<0.25 mm). This study aims to present the advantages of applying a mineral detection routine initially developed for gold grains counting and characterization, to platinum-group minerals in <50 µm till heavy mineral concentrates. This technique, which uses an automated scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer, can provide quantitative mineralogical and semi-quantitative chemical data of heavy minerals of interest, simultaneously. This work presents the mineralogical and chemical characteristics, the grain size distribution, and the surface textures of 2664 discrete platinum-group mineral grains recovered from the processing of 5194 glacial sediment samples collected from different zones in the Canadian Shield (mostly Quebec and Ontario provinces). Fifty-eight different platinum-group mineral species have been identified to date, among which sperrylite (PtAs2) is by far the most abundant (n = 1488; 55.86%). Textural and mineral-chemical data suggest that detrital platinum-group minerals in the studied samples have been derived, at least in part, from Au-rich ore systems.
A Provenance Study of Upper Jurassic Hydrocarbon Source Rocks of the Flemish Pass Basin and Central Ridge, Offshore Newfoundland, Canada
Authors: Scott Matthew , Sylvester Paul J. , Wilton Derek H. C.
Published: March 2021

A number of hydrocarbon discoveries have been made recently in the Flemish Pass Basin and Central Ridge, offshore Newfoundland, Canada, but there is only limited geological information available. The primary goal of this study was to determine the sedimentary provenance and paleodrainage patterns of mudstones and sandstones from the Upper Jurassic Rankin Formation, including the Upper and Lower Kimmeridgian Source Rock (organic-rich shale) members and Upper and Lower Tempest Sandstone Member reservoirs, in this area. A combination of heavy mineral analysis, whole-rock geochemistry and detrital zircon U-Pb geochronology was determined from cores and cuttings from four offshore wells in an attempt to decipher provenance. Detrital heavy minerals in 20 cuttings samples from the studied geologic units are dominated by either rutile + zircon + apatite ± chromite or rutile + apatite + tourmaline, with minor zircon, indicating diverse source lithologies. Whole rock Zr-Th-Sc trends suggest significant zircon recycling in both mudstones and sandstones. Detrital zircon U-Pb ages were determined in two mudstone and four sandstone samples from the four wells. Five major U-Pb age groups of grains were found: A Late Jurassic group that represents an unknown source of syn-sedimentary magmatism, a Permian–Carboniferous age group which is interpreted to be derived from Iberia, a Cambrian–Devonian group derived from the Central Mobile Belt of the Newfoundland–Ireland conjugate margin, and two older age groups (late Neoproterozoic and >1 Ga) linked to Avalonia. The Iberian detritus is abundant in the Central Ridge and southern Flemish Pass region and units containing sizable populations of these grains are interpreted to be derived from the east whereas units lacking this population are interpreted to be sourced from the northeast and possibly also the west. The Upper Tempest Sandstone contains Mesozoic zircons, which constrain the depositional age of this unit to be no older than Late Tithonian.
Investigation of Fractal Carbon Nanotube Networks for Biophilic Neural Sensing Applications
Authors: Browning Leo A. , Watterson William , Happe Erica , Silva Savannah , Abril Valenzuela Roberto , Smith Julian , Dierkes Marissa P. , Taylor Richard P. , Plank Natalie O. V. , Marlow Colleen A.
Published: March 2021

We propose a carbon-nanotube-based neural sensor designed to exploit the electrical sensitivity of an inhomogeneous fractal network of conducting channels. This network forms the active layer of a multi-electrode field effect transistor that in future applications will be gated by the electrical potential associated with neuronal signals. Using a combination of simulated and fabricated networks, we show that thin films of randomly-arranged carbon nanotubes (CNTs) self-assemble into a network featuring statistical fractal characteristics. The extent to which the network’s non-linear responses will generate a superior detection of the neuron’s signal is expected to depend on both the CNT electrical properties and the geometric properties of the assembled network. We therefore perform exploratory experiments that use metallic gates to mimic the potentials generated by neurons. We demonstrate that the fractal scaling properties of the network, along with their intrinsic asymmetry, generate electrical signatures that depend on the potential’s location. We discuss how these properties can be exploited for future neural sensors.
Influence of TOPO and TOPO-CdSe/ZnS Quantum Dots on Luminescence Photodynamics of InP/InAsP/InPHeterostructure Nanowires
Authors: Khrebtov Artem I. , Danilov Vladimir V. , Kulagina Anastasia S. , Reznik Rodion R. , Skurlov Ivan D. , Litvin Alexander P. , Safin Farrukh M. , Gridchin Vladislav O. , Shevchuk Dmitriy S. , Shmakov Stanislav V. , Yablonskiy Artem N. , Cirlin George E.
Published: March 2021

The passivation influence by ligands coverage with trioctylphosphine oxide (TOPO) and TOPO including colloidal CdSe/ZnS quantum dots (QDs) on optical properties of the semiconductor heterostructure, namely an array of InP nanowires (NWs) with InAsP nanoinsertion grown by Au-assisted molecular beam epitaxy on Si (111) substrates, was investigated. A significant dependence of the photoluminescence (PL) dynamics of the InAsP insertions on the ligand type was shown, which was associated with the changes in the excitation translation channels in the heterostructure. This change was caused by a different interaction of the ligand shells with the surface of InP NWs, which led to the formation of different interfacial low-energy states at the NW-ligand boundary, such as surface-localized antibonding orbitals and hybridized states that were energetically close to the radiating state and participate in the transfer of excitation. It was shown that the quenching of excited states associated with the capture of excitation to interfacial low-energy traps was compensated by the increasing role of the “reverse transfer” mechanism. As a result, the effectiveness of TOPO-CdSe/ZnS QDs as a novel surface passivation coating was demonstrated.
Vitamin D Status, Bone Mineral Density, and VDR Gene Polymorphism in a Cohort of Belarusian Postmenopausal Women
Authors: Marozik Pavel , Rudenka Alena , Kobets Katsiaryna , Rudenka Ema
Published: March 2021

Vitamin D plays an important role in bone metabolism and is important for the prevention of multifactorial pathologies, including osteoporosis (OP). The biological action of vitamin is realized through its receptor, which is coded by the VDR gene. VDR gene polymorphism can influence individual predisposition to OP and response to vitamin D supplementation. The aim of this work was to reveal the effects of VDR gene ApaI rs7975232, BsmI rs1544410, TaqI rs731236, FokI rs2228570, and Cdx2 rs11568820 variants on bone mineral density (BMD), 25-hydroxyvitamin D level, and OP risk in Belarusian women. Methods. The case group included 355 women with postmenopausal OP, and the control group comprised 247 women who met the inclusion criteria. TaqMan genotyping assay was used to determine VDR gene variants. Results. Rs7975232 A/A, rs1544410 T/T, and rs731236 G/G single variants and their A-T-G haplotype showed a significant association with increased OP risk (for A-T-G, OR = 1.8, p = 0.0001) and decreased BMD (A-T-G, −0.09 g/cm2, p = 0.0001). The rs11568820 A-allele showed a protective effect on BMD (+0.22 g/cm2, p = 0.027). A significant dose effect with 25(OH)D was found for rs1544410, rs731236, and rs11568820 genotypes. Rs731236 A/A was associated with the 25(OH)D deficiency state. Conclusion. Our novel data on the relationship between VDR gene variants and BMD, 25(OH)D level, and OP risk highlights the importance of genetic markers for personalized medicine strategy.
In Silico and In Vitro Tailoring of a Chitosan Nanoformulation of a Human Metabolic Enzyme
Authors: Lino Paulo R. , Leandro João , Amaro Mariana , Gonçalves Lídia M. D. , Leandro Paula , Almeida António J.
Published: March 2021

Enzyme nanoencapsulation holds an enormous potential to develop new therapeutic approaches to a large set of human pathologies including cancer, infectious diseases and inherited metabolic disorders. However, enzyme formulation has been limited by the need to maintain the catalytic function, which is governed by protein conformation. Herein we report the rational design of a delivery system based on chitosan for effective encapsulation of a functionally and structurally complex human metabolic enzyme through ionic gelation with tripolyphosphate. The rationale was to use a mild methodology to entrap the multimeric multidomain 200 kDa human phenylalanine hydroxylase (hPAH) in a polyol-like matrix that would allow an efficient maintenance of protein structure and function, avoiding formulation stress conditions. Through an in silico and in vitro based development, the particulate system was optimized with modulation of nanomaterials protonation status, polymer, counterion and protein ratios, taking into account particle size, polydispersity index, surface charge, particle yield production, protein free energy of folding, electrostatic surface potential, charge, encapsulation efficiency, loading capacity and transmission electron microscopy morphology. Evaluation of the thermal stability, substrate binding profile, relative enzymatic activity, and substrate activation ratio of the encapsulated hPAH suggests that the formulation procedure does not affect protein stability, allowing an effective maintenance of hPAH biological function. Hence, this study provides an important framework for an enzyme formulation process.
Synthesis of Two Methotrexate Prodrugs for Optimizing Drug Loading into Liposomes
Authors: Di Francesco Valentina , Di Francesco Martina , Decuzzi Paolo , Palomba Roberto , Ferreira Miguel
Published: March 2021

Methotrexate (MTX), a compound originally used as an anticancer drug, has also found applications in a broad variety of autoimmune disorders thanks to its anti-inflammation and immunomodulatory functions. The broad application of MTX is anyway limited by its poor solubility in biological fluids, its poor bioavailability and its toxicity. In addition, encapsulating its original form in nanoformulation is very arduous due to its considerable hydrophobicity. In this work, two strategies to efficiently encapsulate MTX into liposomal particles are proposed to overcome the limitations mentioned above and to improve MTX bioavailability. MTX solubility was increased by conjugating the molecule to two different compounds: DSPE and PEG. These two compounds commonly enrich liposome formulations, and their encapsulation efficiency is very high. By using these two prodrugs (DSPE-MTX and PEG-MTX), we were able to generate liposomes comprising one or both of them and characterized their physiochemical features and their toxicity in primary macrophages. These formulations represent an initial step to the development of targeted liposomes or particles, which can be tailored for the specific application MTX is used for (cancer, autoimmune disease or others).
A Review on X-ray Excited Emission Decay Dynamics in Inorganic Scintillator Materials
Authors: Kumar Vineet , Luo Zhiping
Published: March 2021

Scintillator materials convert high-energy radiation into photons in the ultraviolet to visible light region for radiation detection. In this review, advances in X-ray emission dynamics of inorganic scintillators are presented, including inorganic halides (alkali-metal halides, alkaline-earth halides, rare-earth halides, oxy-halides, rare-earth oxyorthosilicates, halide perovskites), oxides (binary oxides, complex oxides, post-transition metal oxides), sulfides, rare-earth doped scintillators, and organic-inorganic hybrid scintillators. The origin of scintillation is strongly correlated to the host material and dopants. Current models are presented describing the scintillation decay lifetime of inorganic materials, with the emphasis on the short-lived scintillation decay component. The whole charge generation and the de-excitation process are analyzed in general, and an essential role of the decay kinetics is the de-excitation process. We highlighted three decay mechanisms in cross luminescence emission, exitonic emission, and dopant-activated emission, respectively. Factors regulating the origin of different luminescence centers controlling the decay process are discussed.
Fused Filament Fabrication of Polymers and Continuous Fiber-Reinforced Polymer Composites: Advances in Structure Optimization and Health Monitoring
Authors: Mashayekhi Fatemeh , Bardon Julien , Berthé Vincent , Perrin Henri , Westermann Stephan , Addiego Frédéric
Published: March 2021

3D printed neat thermoplastic polymers (TPs) and continuous fiber-reinforced thermoplastic composites (CFRTPCs) by fused filament fabrication (FFF) are becoming attractive materials for numerous applications. However, the structure of these materials exhibits interfaces at different scales, engendering non-optimal mechanical properties. The first part of the review presents a description of these interfaces and highlights the different strategies to improve interfacial bonding. The actual knowledge on the structural aspects of the thermoplastic matrix is also summarized in this contribution with a focus on crystallization and orientation. The research to be tackled to further improve the structural properties of the 3D printed materials is identified. The second part of the review provides an overview of structural health monitoring technologies relying on the use of fiber Bragg grating sensors, strain gauge sensors and self-sensing. After a brief discussion on these three technologies, the needed research to further stimulate the development of FFF is identified. Finally, in the third part of this contribution the technology landscape of FFF processes for CFRTPCs is provided, including the future trends.
Assessing the Influence of Dyes Physico-Chemical Properties on Incorporation and Release Kinetics in Silk Fibroin Matrices
Authors: Tomoda Bruno Thorihara , Pacheco Murilo Santos , Abranches Yasmin Broso , Viganó Juliane , Perrechil Fabiana , De Moraes Mariana Agostini
Published: March 2021

Silk fibroin (SF) is a promising and versatile biodegradable protein for biomedical applications. This study aimed to develop a prolonged release device by incorporating SF microparticles containing dyes into SF hydrogels. The influence of dyes on incorporation and release kinetics in SF based devices were evaluated regarding their hydrophilicity, molar mass, and cationic/anionic character. Hydrophobic and cationic dyes presented high encapsulation efficiency, probably related to electrostatic and hydrophobic interactions with SF. The addition of SF microparticles in SF hydrogels was an effective method to prolong the release, increasing the release time by 10-fold.
Financial Transactions Using FINTECH during the Covid-19 Crisis in Bulgaria
Authors: Vasenska Ivanka , Dimitrov Preslav , Koyundzhiyska-Davidkova Blagovesta , Krastev Vladislav , Durana Pavol , Poulaki Ioulia
Published: March 2021

In the context of current crises following COVID-19 and growing global economic uncertainties, the issues regarding financial transactions with FINTECH are increasingly apparent. Consequently, in our opinion, the utilization of FINTECH financial transactions leads to a risk-reduction approach when in contact with other people. Moreover, financial transactions with FINTECH can save up customers’ pecuniary funds. Therefore, during crises, FINTECH applications can be perceived as more competitive than the traditional banking system. All the above have provoked us to conduct research related to the utilization of financial transactions with FINTECH before and after the COVID-19 crisis outbreak. The aim of the article is to present a survey analysis of FINTECH utilization of individual customers before and after the crisis in Bulgaria. The methodology includes a questionnaire survey of 242 individual respondents. For the data processing, we implemented statistical measures and quantitative methods, including two-sample paired t-tests, Levene’s test, and ANOVAs performed through the computer language Python in a web-based interactive computing environment for creating documents, Jupyter Notebook. The findings bring out the main issues related to the implementation of financial transactions with FINTECH under the conditions of the crisis. The findings include the identification of problems related to FINTECH transactions during the COVID-19 crisis in Bulgaria.
Centralized Multi-Hop Routing Based on Multi-Start Minimum Spanning Forest Algorithm in the Wireless Sensor Networks
Authors: Jin Rencheng , Fan Xiaolei , Sun Ting
Published: March 2021

Wireless sensor networks (WSNs) are widely applied in environmental monitoring, target tracking, military, and industrial fields. However, the battery energy of sensor nodes in WSNs is limited, which limits its development. Previous studies have shown that clustering protocols and multi-hop communication are beneficial to reduce nodes energy consumption. The multi-hop protocol based on low energy adaptive clustering hierarchy (LEACH) has been proven to significantly reduce energy dissipation. However, LEACH-based multi-hop protocols generally have the problem of unbalanced energy dissipation and data conflicts. In this paper, we propose a centralized multi-hop routing based on multi-start minimum spanning forest (LEACH-CMF) to optimize LEACH. In order to realize multi-hop communication, we introduced a multi-start minimum spanning tree algorithm to select relay nodes with the minimum relay cost and generate appropriate multi-hop paths. To avoid data collision in multi-hop communication and make nodes including the cluster heads sleep as much as possible in the non-working state, we design a bottom-up continuous time slot allocation method to improve the time division multiple access (TDMA) cycle. We performed simulation in NS2. The simulation results show that the network lifetime is approximately doubled compared to LEACH and centralized low energy adaptive clustering hierarchy (LEACH-C). The simulation results show that the proposed protocol can effectively balance the energy dissipation of nodes and prolong network lifetime.