bluuebunny/crossref_metadata_2025 huggingface dataset:
Melatonin as a Topical/Systemic Formulation for the Management of Periodontitis: A Systematic Review
Authors: Balaji Thodur Madapusi , Varadarajan Saranya , Jagannathan Raghunathan , Mahendra Jaideep , Fageeh Hammam Ibrahim , Fageeh Hytham N. , Mushtaq Shazia , Baeshen Hosam Ali , Bhandi Shilpa , Gupta Archana A. , Raj A. Thirumal , Reda Rodolfo , Patil Shankaragouda , Testarelli Luca
Published: May 2021

Objectives: To qualitatively and quantitatively review the use of melatonin as a topical/systemic formulation for the management of periodontitis. Materials and methods: PubMed; Scopus; and Web of Science databases were searched using the MesH terms “melatonin” and “periodontitis”. Title and abstracts were screened to eliminate irrelevant and duplicate articles. The full text data of the screened articles were assessed using the selection criteria. Results: Of 176 identified articles (PubMed-66; Scopus-56; Web of Science-52; Cross-reference-2), only 12 studies qualified to be included in the systematic review. Four studies assessed the independent effect of 1% topical melatonin formulation while 8 articles assessed the adjunctive use of systemic melatonin formulation (1–10 mg) following scaling and root planing (SRP). All studies showed an improvement in periodontal parameters such as pocket depth, clinical attachment loss, periodontal disease index, community periodontal index, gingival bleeding scores, and prognostic marker levels in saliva and serum. A meta-analysis of data from 2 studies revealed that 1–2 mg (systemic) melatonin supplementation reduced pocket depth; although the difference was not statistically significant and hence cannot be interpreted or used for conclusive evidence. Risk of Bias Assessment tool (RoBANS) and Cochrane Collaboration RoB tool elicited a high risk of bias in the included studies. GRADE (recommendation assessment, development, and evaluation) inferred a weak recommendation for the use of melatonin in periodontitis management. Conclusions: Melatonin supplementation (topical and systemic) in periodontitis patients improved key periodontal parameters including pocket depth and clinical attachment loss. Clinical relevance: Melatonin could be a potential host modulatory agent for periodontitis management; although the data from the present review should be interpreted carefully due to the associated high risk of bias.
Silicone Composites with CNT/Graphene Hybrid Fillers: A Review
Authors: Barshutina Marie N. , Volkov Valentyn S. , Arsenin Aleksey V. , Nasibulin Albert G. , Barshutin Sergey N. , Tkachev Alexey G.
Published: May 2021

This review is dedicated to versatile silicone rubber composites based on carbon nanotube/graphene (CNT/G) hybrid fillers. Due to their unique mechanical, electrical, thermal, and biological properties, such composites have enormous potential for medical, environmental, and electronics applications. In the scope of this paper, we have explored CNT/graphene/silicone composites with a different morphology, analyzed the synergistic effect of hybrid fillers on various properties of silicone composites, and observed the existing approaches for the fabrication of hybrid composites with a seamless, assembled, and/or foamed structure. In conclusion, current challenges and future prospects for silicone composites based on CNTs and graphene have been thoroughly discussed.
Injectiveness and Discontinuity of Multiplicative Convex Functions
Authors: Jiménez-Rodríguez Pablo , Martínez-Gómez María E. , Muñoz-Fernández Gustavo A. , Seoane-Sepúlveda Juan B.
Published: May 2021

In the present work we study the set of multiplicative convex functions. In particular, we focus on the properties of injectiveness and discontinuity. We will show that a non constant multiplicative convex function is at most 2-injective, and construct multiplicative convex functions which are discontinuous at infinitely many points.
Fabrication and Characterization of a Microscale Piezoelectric Vibrator Based on Electrohydrodynamic Jet Printed PZT Thick Film
Authors: Wang Dazhi , Zhao Kuipeng , Yuan Yuheng , Wang Zhu , Zong Haoran , Zhang Xi , Liang Junsheng
Published: May 2021

This paper proposes a novel way of preparing a PZT thick film micro vibrator using the electrohydrodynamic jet (E-Jet) printing technique. Initially, a micro piezoelectric vibrator was simulated and designed for obtaining optimized structure, which has a total thickness of less than 600 µm. Subsequently, the PZT thick film element was directly printed on the elastic body using the E-Jet printing. This method avoids the glue fabrication process involved in the bulk piezoelectric fabrication, thus avoiding the limits of voltage drops, isolating and absorbing amplitude usually occurred in the vibrator having glue interface. It was observed that B02 and B03 modes were generated at frequencies of 29.74 and 79.14 kHz, respectively, and the amplitudes of B02 and B03 modes were 406 and 176 nm, respectively. The error between the simulation and test result in the B03 modal is only 0.35%, which indicates the accuracy of the simulation analysis and the fabrication process. The PZT thick film traveling-wave micro vibrator successfully realized bidirectional rotation of a rotor, with a maximum speed of 681 rpm, which also shows a linear relationship between excitation voltage and rotary speed. This paper provides an effective method for preparing a micro piezoelectric vibrator for MEMS ultrasonic devices, which simplifies the manufacturing process and enhances the performance of the piezoelectric vibrator.
Synthesis and Evaluation of Chalcone Derivatives as Novel Sunscreen Agent
Authors: Wijayanti Lucia Wiwid , Swasono Respati Tri , Lee Wonkoo , Jumina Jumina
Published: May 2021

Ultraviolet (UV) irradiation is a serious problem for skin health thus the interest in the research to develop sunscreen agent has been increasing. Chalcone is a promising compound to be developed as its chromophore absorbs in the UV region. Therefore, in the present work, we synthesized eight chalcone derivatives through Claisen–Schmidt condensation at room temperature. The evaluation of the optical properties of each chalcone derivatives in the UV region was conducted through spectroscopic and computational studies. The synthesized chalcones were obtained in good yields and they were active in the UV region. The results revealed that more methoxy substituents to chalcone leads toward red shift. All chalcone derivatives have high molar absorptivity value (21,000–56,000) demonstrating that they have the potential to be used as the sunscreen agent. The cytotoxicity assay showed that chalcone derivatives were demonstrating low toxicity toward normal human fibroblast cell, which is remarkable. Therefore, we concluded that the synthesized chalcones in this work were potential to be developed as novel sunscreen agents in real application.
Epoxy Nanocomposites with Carbon Nanotubes Produced by Floating Catalyst CVD
Authors: Mordkovich Vladimir Z. , Kondrashov Stanislav V. , Karaeva Aida R. , Urvanov Sergey A. , Kazennov Nikita V. , Mitberg Eduard B. , Pushina Ekaterina A.
Published: May 2021

Epoxy nanocomposites with float catalysis-produced CNT felt as a filler were prepared. Parameters such as the curing process, glass transition of epoxynanocomposites, structure and morphology of CNT felt, initial epoxy composition, and epoxy nanocomposites were investigated. The influence of CNT felt on curing process in epoxy nanocomposites with different amounts of curing agent was determined. An exothermic reaction between the curing agent and the surface of CNTs was established. It was found that the structure of epoxy nanocomposites has a high degree of heterogeneity: the presence of fiber-like structures and individualized CNTs is observed together with the regions that are typical for CNTs that are fabricated via a catalytic chemical vapor deposition (CVD). Based on the studies performed, it is possible to predict the production of epoxy nanocomposites with outstanding mechanical and thermophysical properties. In particular, the uncured compositions already obtained in this work can be used for the manufacture of electrically conductive glass and carbon fiber reinforced plastics and functional coatings.
An Inverted Honeycomb Plasmonic Lattice as an Efficient Refractive Index Sensor
Authors: Rodríguez-Álvarez Javier , Gnoatto Lorenzo , Martínez-Castells Marc , Guerrero Albert , Borrisé Xavier , Fraile Rodríguez Arantxa , Batlle Xavier , Labarta Amílcar
Published: May 2021

We present an efficient refractive index sensor consisting of a heterostructure that contains an Au inverted honeycomb lattice as a main sensing element. Our design aims at maximizing the out-of-plane near-field distributions of the collective modes of the lattice mapping the sensor surroundings. These modes are further enhanced by a patterned SiO2 layer with the same inverted honeycomb lattice, an SiO2 spacer, and an Au mirror underneath the Au sensing layer that contribute to achieving a high performance. The optical response of the heterostructure was studied by numerical simulation. The results corresponding to one of the collective modes showed high sensitivity values ranging from 99 to 395 nm/RIU for relatively thin layers of test materials within 50 and 200 nm. In addition, the figure of merit of the sensor detecting slight changes of the refractive index of a water medium at a fixed wavelength was as high as 199 RIU−1. As an experimental proof of concept, the heterostructure was manufactured by a simple method based on electron beam lithography and the measured optical response reproduces the simulations. This work paves the way for improving both the sensitivity of plasmonic sensors and the signal of some enhanced surface spectroscopies.
Energy Balance and Risk of Mortality in Spanish Older Adults
Authors: Lassale Camille , Hernáez Álvaro , Toledo Estefanía , Castañer Olga , Sorlí José V. , Salas-Salvadó Jordi , Estruch Ramon , Ros Emilio , Alonso-Gómez Ángel M. , Lapetra José , Cueto Raquel , Fiol Miquel , Serra-Majem Lluis , Pinto Xavier , Gea Alfredo , Corella Dolores , Babio Nancy , Fitó Montserrat , Schröder Helmut
Published: May 2021

Clinical data on the direct health effects of energy deficit or surplus beyond its impact on body weight are scarce. We aimed to assess the association with all-cause, cardiovascular and cancer mortality of (1) sustained energy deficit or surplus, calculated according to each individual’s en-ergy intake (EI) and theoretical energy expenditure (TEE), and (2) mid-term change in total EI in a prospective study. In 7119 participants in the PREDIMED Study (PREvención con DIeta MEDi-terránea) with a mean age of 67 years, energy intake was derived from a 137-item food frequency questionnaire. TEE was calculated as a function of age, sex, height, body weight and physical ac-tivity. The main exposure was the proportion of energy requirement covered by energy intake, cumulative throughout the follow-up. The secondary exposure was the change in energy intake from baseline. Cox proportional hazard models were used to estimate hazard ratios and 95% con-fidence intervals for all-cause, cardiovascular and cancer mortality. Over a median follow-up of 4.8 years, there were 239 deaths (excluding the first 2 years). An energy intake exceeding energy needs was associated with an increase in mortality risk (continuous HR10% over energy needs = 1.10; 95% CI 1.02, 1.18), driven by cardiovascular death (HR = 1.26; 95% CI 1.11, 1.43). However, consum-ing energy below estimated needs was not associated with a lower risk. Increments over time in energy intake were associated with greater all-cause mortality (HR10% increase = 1.09; 95% CI 1.02, 1.17). However, there was no evidence that a substantial negative change in energy intake would reduce mortality risk. To conclude, in an older Mediterranean cohort, energy surplus or increase over a 5-year period was associated with greater risk of mortality, particularly cardiovascular mortality. Energy deficit, or reduction in energy intake over time were not associated with mortal-ity risk.
Effect of the Intake of a Traditional Mexican Beverage Fermented with Lactic Acid Bacteria on Academic Stress in Medical Students
Authors: Márquez-Morales Laura , El-Kassis Elie G. , Cavazos-Arroyo Judith , Rocha-Rocha Valeria , Martínez-Gutiérrez Fidel , Pérez-Armendáriz Beatriz
Published: May 2021

Dysbiosis of the gut microbiota has been associated with different illnesses and emotional disorders such as stress. Traditional fermented foods that are rich in probiotics suggest modulation of dysbiosis, which protects against stress-induced disorders. The academic stress was evaluated in medical students using the SISCO Inventory of Academic Stress before and after ingestion of an aguamiel-based beverage fermented with Lactobacillus plantarum, Lactobacillus paracasei and Lactobacillus brevis (n = 27) and a control group (n = 18). In addition, microbial phyla in feces were quantified by qPCR. The results showed that the consumption of 100 mL of a beverage fermented with lactic acid bacteria (3 × 108 cfu/mL) for 8 weeks significantly reduced academic stress (p = 0.001), while the control group (placebo intervention) had no significant changes in the perception of academic stress (p = 0.607). Significant change (p = 0.001) was shown in the scores for environmental demands, and physical and psychological factors. Consumption of the fermented beverage significantly increased the phyla Firmicutes and Bacteroidetes but not Gammaproteobacteria. No significant changes were found in the control group, except for a slight increase in the phylum Firmicutes. The intake of this fermented beverage suggest a modulation of gut microbiota and possible reduction in stress-related symptoms in university students, without changing their lifestyle or diet.
Association between Sugar Intake and Intima Media Thickness as a Marker for Atherosclerosis: A Cross-Sectional Study in the Malmö Diet and Cancer Study (Sweden)
Authors: González-Padilla Esther , Janzi Suzanne , Ramne Stina , Thuneland Camilla , Borné Yan , Sonestedt Emily
Published: May 2021

It has been suggested that sugar intake may play a role in the development of atherosclerosis. However, studies on this matter are lacking. Intima media thickness (IMT) is a well-established measurement of subclinical atherosclerosis. This study aimed to investigate the cross-sectional association between sugar intake (i.e., added, free and total sugar and sugar-rich foods and beverages) and IMT. Our study comprised 5269 individuals (45–73 years, 40% men) of the Malmö Diet and Cancer Study, a population-based cohort conducted in Sweden with data collected from 1991 to 1994. Measurements of IMT were performed with B-mode ultrasound at the right common carotid artery (IMTcca) and the bifurcation of the carotids (IMTbif). Dietary intake was estimated using a combination of a 7-day food record, diet questionnaire and interview. After adjusting for methodological, lifestyle and dietary confounders, no statistically significant associations were observed for any of the sugar intake variables and IMT. For example, added sugar intake presented no significant linear association with IMTcca or IMTbif (Ptrends: IMTcca 0.81 for men and 0.98 for women and IMTbif 0.20 for men and 0.40 for women). In conclusion, we found no clear association between sugar intake and IMT measurements in this study.
Periconceptional Folate Supplementation in Women after Bariatric Surgery—A Narrative Review
Authors: Vynckier An-Katrien , Ceulemans Dries , Vanheule Greet , De Mulder Paulien , Van Den Driessche Mieke , Devlieger Roland
Published: May 2021

The prevalence of obesity is increasing globally, and along with it, there is a growing number of patients opting to undergo bariatric surgery to treat this condition. Whilst it has many advantages, bariatric surgery is known to induce micronutrient deficiency, with possible deleterious effects on overall health. This topic becomes even more relevant during pregnancy, where deficiencies can also affect the developing fetus, possibly being the cause of an increase in congenital anomalies. Most notably amongst these micronutrients is folate, or vitamin B9, which plays an essential role in development, gene expression and genomic stability. As insufficient levels of folate are associated with neural tube defects in the fetus, preventing and treating folate deficiencies during pregnancies after bariatric surgery is a relevant issue. Unfortunately, folate supplementation recommendations for bariatric patients who wish to become pregnant are not clear. In this narrative review, we discuss whether the recommendations for the general population are still valid for bariatric patients. Furthermore, we discuss the role of folate in the human body, folate status in both non-bariatric and bariatric patients, the various types of folate that are available for substitution and the risk associated with over-supplementation.
Zinc Affects Cholesterol Oxidation Products and Fatty Acids Composition in Rats’ Serum
Authors: Stawarska Agnieszka , Czerwonka Małgorzata , Wyrębiak Rafał , Wrzesień Robert , Bobrowska-Korczak Barbara
Published: May 2021

The purpose of this work was to evaluate the effect of the nanosized or microsized zinc (Zn) particles on fatty acid profile, enzyme activity and the level of cholesterol, squalene and oxysterols in rats with breast cancer. Rats (female, n = 24) were divided into the following groups: control, and two test groups, whose diets were enriched with either Zn microparticles (342 nm) or Zn nanoparticles (99 nm). All rats were treated twice with the carcinogenic agent; 7,12-dimethylbenz[a]anthracene. In rats whose diet was enriched with zinc (especially in the form of nanoparticles), the number and sizes of tumors were lower. Diet supplementation also significantly reduced the cholesterol (p = 0.027) and COPs (cholesterol oxidation products) levels (p = 0.011) in rats serum. Enriching the diet with Zn microparticles decreased the Δ6-desaturase activity (p < 0.001). Zn influences fatty acids’ profile in rats’ serum as well as inhibiting desaturating enzymes. A reduced amount of pro-inflammatory arachidonic acid derivatives may be the expected effect.
Cold-Start Problems in Data-Driven Prediction of Drug–Drug Interaction Effects
Authors: Dewulf Pieter , Stock Michiel , De Baets Bernard
Published: May 2021

Combining drugs, a phenomenon often referred to as polypharmacy, can induce additional adverse effects. The identification of adverse combinations is a key task in pharmacovigilance. In this context, in silico approaches based on machine learning are promising as they can learn from a limited number of combinations to predict for all. In this work, we identify various subtasks in predicting effects caused by drug–drug interaction. Predicting drug–drug interaction effects for drugs that already exist is very different from predicting outcomes for newly developed drugs, commonly called a cold-start problem. We propose suitable validation schemes for the different subtasks that emerge. These validation schemes are critical to correctly assess the performance. We develop a new model that obtains AUC-ROC =0.843 for the hardest cold-start task up to AUC-ROC =0.957 for the easiest one on the benchmark dataset of Zitnik et al. Finally, we illustrate how our predictions can be used to improve post-market surveillance systems or detect drug–drug interaction effects earlier during drug development.
Magnesium in Ketamine Administration in Treatment-Resistant Depression
Authors: Górska Natalia , Cubała Wiesław Jerzy , Słupski Jakub , Wiglusz Mariusz Stanisław , Gałuszko-Węgielnik Maria , Kawka Mateusz , Grzegorzewska Agata
Published: May 2021

Relationship between depression and magnesium levels is reported. This observational study examined whether serum magnesium concentration change over time of ketamine treatment course, also whether association between magnesium concentrations and treatment response measured with Montgomery-Åsberg Depression Rating Scale (MADRS) score occurs. Moreover, interlink between changes in Young Mania Rating Scale (YMRS) score, somatic comorbidities, and magnesium concentration was studied. Inpatients with major depressive disorder or bipolar disorder were rated weekly by clinician using MADRS and YMRS. Magnesium levels assessments were carried out weekly, before start of ketamine treatment and then every second infusion and one week after last ketamine infusion. The concentration of Mg2+ ions differs depending on the measurement. The Mg2+ concentration in pre-measurement was significantly higher than in measurement after five infusions (p = 0.031) and after seven infusions (p = 0.003). No significant correlation was observed between changes in magnesium serum levels and MADRS or YMRS. The concentration of Mg2+ ion in course of the treatment was not associated with somatic comorbidities. The study supports data for role of magnesium in treatment-resistant depression, particularly related to ketamine treatment, but provides no clear evidence of straightforward association between magnesium serum concentration and treatment response or comorbidity.
The Interest of a Systematic Toxicological Analysis Combined with Forensic Advice to Improve the Judicial Investigation and Final Judgment in Drug Facilitated Sexual Assault Cases
Authors: Wille Sarah M. R. , Van Dijck Karolien , Van Assche Antje , Di Fazio Vincent , Ramiréz-Fernandéz Maria del Mar , Vanvooren Vanessa , Samyn Nele
Published: May 2021

The conviction rate in drug facilitated sexual assault (DFSA) cases is known to be very low. In addition, the potential impact of toxicological results on the case is often not well understood by the judicial authorities. The aims of this study were (1) to obtain more knowledge concerning the prevalence of incapacitating substances in DFSA cases, (2) to create a more efficient DFSA analysis strategy taking background information into account, and (3) to evaluate the potential impact of systematic toxicological analysis (STA) on the final judicial outcome. This small-scale epidemiological study (n = 79) demonstrates that ‘commonly-used’ illicit drugs, psychoactive medicines and ethanol are more prevalent in DFSA cases in contrast to the highly mediatized date rape drugs. Additionally, via case examples, the interest of performing STA—to prove incapacitation of the victim—in judicial procedures with mutual-consent discussions has been demonstrated as it led to increased convictions. However, more attention has to be paid to ensure a short sampling delay and to get more accurate information from the medical treatment of the alleged victim. This will improve the interpretation of the toxicological analysis and thus its applicability in a DFSA case. The future is multi-disciplinary and will certainly lead to an efficient and more cost-effective DFSA approach in which STA can impact the final judgment.
Mutual Effects of Hydrogen Bonding and Polymer Hydrophobicity on Ibuprofen Crystal Inhibition in Solid Dispersions with Poly(N-vinyl pyrrolidone) and Poly(2-oxazolines)
Authors: Shan Xiaoning , Moghul Maryam A. , Williams Adrian C. , Khutoryanskiy Vitaliy V.
Published: May 2021

Poly(N-vinyl pyrrolidone) (PVP), poly(2-methyl-2-oxazoline) (PMOZ), poly(2-ethyl-2-oxazoline) (PEOZ), poly(2-n-propyl-2-oxazoline) (PnPOZ), and poly(2-isopropyl-2-oxazoline) (PiPOZ) were used to prepare solid dispersions with ibuprofen (IB), a model poorly-water soluble drug. Dispersions, prepared by solvent evaporation, were investigated using powder X-ray diffractometry, differential scanning calorimetry, and FTIR spectroscopy; hydrogen bonds formed between IB and all polymers in solid dispersions. PMOZ, the most hydrophilic polymer, showed the poorest ability to reduce or inhibit the crystallinity of IB. In contrast, the more hydrophobic polymers PVP, PEOZ, PnPOZ, and PiPOZ provided greater but similar abilities to reduce IB crystallinity, despite the differing polymer hydrophobicity and that PiPOZ is semi-crystalline. These results indicate that crystallinity disruption is predominantly due to hydrogen bonding between the drug molecules and the polymer. However, carrier properties affected drug dissolution, where PnPOZ exhibited lower critical solution temperature that inhibited the release of IB, whereas drug release from other systems was consistent with the degree of ibuprofen crystallinity within the dispersions.
Interactions with Microbial Proteins Driving the Antibacterial Activity of Flavonoids
Authors: Donadio Giuliana , Mensitieri Francesca , Santoro Valentina , Parisi Valentina , Bellone Maria Laura , De Tommasi Nunziatina , Izzo Viviana , Dal Piaz Fabrizio
Published: May 2021

Flavonoids are among the most abundant natural bioactive compounds produced by plants. Many different activities have been reported for these secondary metabolites against numerous cells and systems. One of the most interesting is certainly the antimicrobial, which is stimulated through various molecular mechanisms. In fact, flavonoids are effective both in directly damaging the envelope of Gram-negative and Gram-positive bacteria but also by acting toward specific molecular targets essential for the survival of these microorganisms. The purpose of this paper is to present an overview of the most interesting results obtained in the research focused on the study of the interactions between flavonoids and bacterial proteins. Despite the great structural heterogeneity of these plant metabolites, it is interesting to observe that many flavonoids affect the same cellular pathways. Furthermore, it is evident that some of these compounds interact with more than one target, producing multiple effects. Taken together, the reported data demonstrate the great potential of flavonoids in developing innovative systems, which can help address the increasingly serious problem of antibiotic resistance.
Application of Machine-Learning Algorithms for Better Understanding of Tableting Properties of Lactose Co-Processed with Lipid Excipients
Authors: Djuris Jelena , Cirin-Varadjan Slobodanka , Aleksic Ivana , Djuris Mihal , Cvijic Sandra , Ibric Svetlana
Published: May 2021

Co-processing (CP) provides superior properties to excipients and has become a reliable option to facilitated formulation and manufacturing of variety of solid dosage forms. Development of directly compressible formulations with high doses of poorly flowing/compressible active pharmaceutical ingredients, such as paracetamol, remains a great challenge for the pharmaceutical industry due to the lack of understanding of the interplay between the formulation properties, process of compaction, and stages of tablets’ detachment and ejection. The aim of this study was to analyze the influence of the compression load, excipients’ co-processing and the addition of paracetamol on the obtained tablets’ tensile strength and the specific parameters of the tableting process, such as (net) compression work, elastic recovery, detachment, and ejection work, as well as the ejection force. Two types of neural networks were used to analyze the data: classification (Kohonen network) and regression networks (multilayer perceptron and radial basis function), to build prediction models and identify the variables that are predominantly affecting the tableting process and the obtained tablets’ tensile strength. It has been demonstrated that sophisticated data-mining methods are necessary to interpret complex phenomena regarding the effect of co-processing on tableting properties of directly compressible excipients.
Hsa-miR-125b Therapeutic Role in Colon Cancer Is Dependent on the Mutation Status of the TP53 Gene
Authors: Cenariu Diana , Zimta Alina-Andreea , Munteanu Raluca , Onaciu Anca , Moldovan Cristian Silviu , Jurj Ancuta , Raduly Lajos , Moldovan Alin , Florea Adrian , Budisan Liviuta , Pop Laura Ancuta , Magdo Lorand , Albu Mihai Tudor , Tonea Rares Bogdan , Muresan Mihai-Stefan , Ionescu Calin , Petrut Bogdan , Buiga Rares , Irimie Alexandru , Gulei Diana , Berindan-Neagoe Ioana
Published: May 2021

Colon cancer is the third most common cancer type worldwide and is highly dependent on DNA mutations that progressively appear and accumulate in the normal colon epithelium. Mutations in the TP53 gene appear in approximately half of these patients and have significant implications in disease progression and response to therapy. miR-125b-5p is a controversial microRNA with a dual role in cancer that has been reported to target specifically TP53 in colon adenocarcinomas. Our study investigated the differential therapeutic effect of miR-125b-5p replacement in colon cancer based on the TP53 mutation status of colon cancer cell lines. In TP53 mutated models, miR-125b-5p overexpression slows cancer cells’ malignant behavior by inhibiting the invasion/migration and colony formation capacity via direct downregulation of mutated TP53. In TP53 wild type cells, the exogenous modulation of miR-125b-5p did not significantly affect the molecular and phenotypic profile. In conclusion, our data show that miR-125b-5p has an anti-cancer effect only in TP53 mutated colon cancer cells, explaining partially the dual behavior of this microRNA in malignant pathologies.
Direct Writing of Silicon Oxide Nanopatterns Using Photonic Nanojets
Authors: Luo Hao , Yu Haibo , Wen Yangdong , Zheng Jianchen , Wang Xiaoduo , Liu Lianqing
Published: May 2021

The ability to create controllable patterns of micro- and nanostructures on the surface of bulk silicon has widespread application potential. In particular, the direct writing of silicon oxide patterns on silicon via femtosecond laser-induced silicon amorphization has attracted considerable attention owing to its simplicity and high efficiency. However, the direct writing of nanoscale resolution is challenging due to the optical diffraction effect. In this study, we propose a highly efficient, one-step method for preparing silicon oxide nanopatterns on silicon. The proposed method combines femtosecond laser-induced silicon amorphization with a subwavelength-scale beam waist of photonic nanojets. We demonstrate the direct writing of arbitrary nanopatterns via contactless scanning, achieving patterns with a minimum feature size of 310 nm and a height of 120 nm. The proposed method shows potential for the fabrication of multifunctional surfaces, silicon-based chips, and silicon photonics.
A Two-Step Microwave Annealing Process for PAN Pre-Oxidation through a TM-Mode Cavity
Authors: Chen Yan-Ren , Chao Hsien-Wen , Hsu Hung-Chun , Chan Cheng-Hsuan , Lin Wei-Hsiang , Tsai Che-Wei , Chang Tsun-Hsu
Published: May 2021

A novel microwave annealing system and a specific processing condition are proposed for the pre-oxidation of carbon fiber. The microwave annealing system consists of a TM-mode resonant cavity and a silicon carbide (SiC) susceptor. The TM-mode cavity enhances the electric field at the center. The SiC susceptor absorbs part of the microwave energy and converts it to heat. The enhanced fields and the SiC susceptor provide both nonthermal and thermal treatments for fibrous materials with various dielectric properties. Furthermore, a two-step microwave annealing process is used to oxidize polyacrylonitrile (PAN) fiber. The scanning electron microscopy (SEM) images, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) results support the theory that the microwave annealing can achieve a high aromatic index of 66.39% in just 13 min, 9 times faster than the traditional processing time. The results of the Raman spectra also illustrate that the sheath-core factor of the microwave-heated specimen is closer to one than that of the conventional furnace-heated type, which agree with the images of the cross-section area.
Rupture of an Industrial GFRP Composite Mitered Elbow Pipe
Authors: Mahdi Saad Elsadig , Gowid Samer , Cabibihan John John
Published: May 2021

This paper examines the immature rupture of glass fiber reinforced plastic composite (GFRP) mitered elbow pipes. The GFRP composite mitered elbow pipe’s lifespan was twenty-five years; however, the pipes in question experienced immature failures, resulting in the reduction of their lifetimes to seven, nine, and ten years, respectively. The GFRP cooling water mitered elbow pipe’s service conditions operate at a pressure of up to 7 bar and temperatures between 15–36 °C. The root cause of failure was determined using visual inspection, analytical, microstructural, mechanical characterizations, and chemical analysis. The initial visualization inspection revealed an improper joint between the composite overwrapped and the straight pipe sections. Mechanical properties along the axial, hoop and 45° from the axial direction were obtained. The results from the analytical analysis indicated that the elbow might withstand the operating pressure depending on the quality factor, which was confirmed to be low due to the elbow joint’s improper fabrication process. As evidence of this, the numerical analyses’ results indicated that the safety factor in withstanding the operating pressure of 5 bar is dropped down in the radial region where the thickness is reduced to simulate the failure zone. This study’s findings recommend that thickness of less than 15 mm be reinforced using overwrapped composites. It is recommended for future installations that the fabrication process be appropriately monitored and controlled and avoids using 45°/−45° fiber orientation and multiple layers of chopped strand mat glass fiber.
Waste Fiber-Based Poly(hydroxamic acid) Ligand for Toxic Metals Removal from Industrial Wastewater
Authors: Rahman Md. Lutfor , Wong Zhi-Jian , Sarjadi Mohd Sani , Joseph Collin G. , Arshad Sazmal E. , Musta Baba , Abdullah Mohd Harun
Published: May 2021

Toxic metals in the industrial wastewaters have been liable for drastic pollution hence a powerful and economical treatment technology is needed for water purification. For this reason, some pure cellulosic materials were derived from waste fiber to obtain an economical adsorbent for wastewater treatment. Conversion of cellulose into grafting materials such as poly(methyl acrylate)-grafted cellulose was performed by free radical grafting process. Consequently, poly(hydroxamic acid) ligand was produced from the grafted cellulose. The intermediate products and poly(hydroxamic acid) ligand were analyzed by FT-IR, FE-SEM, TEM, EDX, and XPS spectroscopy. The adsorption capacity (qe) of some toxic metals ions by the polymer ligand was found to be excellent, e.g., copper capacity (qe) was 346.7 mg·g−1 at pH 6. On the other hand, several metal ions such as cobalt chromium and nickel also demonstrated noteworthy sorption capacity at pH 6. The adsorption mechanism obeyed the pseudo second-order rate kinetic model due to the satisfactory correlated experimental sorption values (qe). Langmuir model isotherm study showed the significant correlation coefficient with all metal ions (R2 > 0.99), indicating that the single or monolayer adsorption was the dominant mode on the surface of the adsorbent. This polymer ligand showed good properties on reusability. The result shows that the adsorbent may be recycled for 6 cycles without any dropping of starting sorption capabilities. This polymeric ligand showed outstanding toxic metals removal magnitude, up to 90–99% of toxic metal ions can be removed from industrial wastewater.
Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
Authors: Bignotti Fabio , Baldi Francesco , Grassi Mario , Abrami Michela , Spagnoli Gloria
Published: May 2021

This work reports on a novel method to synthesize hydrophobically-modified hydrogels by curing epoxy monomers with amines. The resulting networks contain hydrophilic poly(ethylene glycol) (PEG) segments, poly(propylene glycol) (PPG) segments, and C18 alkyl segments. By varying the content of C18 segments, networks with different hydrophilic-lipophilic balance (HLB) are obtained. All networks show an amphiphilic behavior, swelling considerably both in organic solvents and in aqueous media. In the latter they display a thermosensitive behavior, which is highly affected by the network HLB and the pH of the solution. A decrease in HLB results in an increment of the polymer weight content (wp) due to hydrophobic association. Furthermore, a reduction in HLB induces a remarkable increase in initial modulus, elongation at break and tensile strength, especially when wp becomes greater than about 10%. Low field nuclear magnetic resonance (LF-NMR) experiments evidence that, when HLB decreases, a sudden and considerable increase in hydrogel heterogeneity takes place due to occurrence of extensive physical crosslinking. Available data suggest that in systems with wp ≳ 10% a continuous physical network superimposes to the pre-existing chemical network and leads to a sort of double network capable of considerably improving hydrogel toughness.
High Performance PA 6/Cellulose Nanocomposites in the Interest of Industrial Scale Melt Processing
Authors: Sridhara Pruthvi K. , Vilaseca Fabiola
Published: May 2021

On an industrial scale, it is a challenge to achieve cellulose based nanocomposites due to dispersion issues and high process temperatures sensitivity. The current study describes methods to develop mechanically strong and thermally stable polyamide 6 (PA 6) and cellulose nanofibers (CNF) composites capable of tolerating high processing temperatures. With PA 6 being a very technical polymer matrix to be reinforced with CNF, good dispersion can be achieved with a high speed kinetic mixer and also shield the CNF from excess thermal degradation by implementing extremely short processing time. This paper presents an industrially feasible method to produce PA 6/CNF nanocomposites with high CNF composition processed by a high speed kinetic mixer (GELIMAT®) followed by compression molding to obtain a homogenous and thermally stable nanocomposites aimed at high performance applications. PA 6 was reinforced with three different wt % formulations (5, 15 and 25 wt %) of cellulose nanofibers. The resulting nanocomposites exhibited significant increase in Young’s modulus and ultimate strength with CNF content, owing to the effective melt processing and the surface charge density of the CNF, which necessitated the dispersion. The thermal stability and polymer crystallinity with respect to CNF composition for the PA 6/CNF nanocomposites were examined by TGA and DSC analysis. Rheology studies indicated that viscosity of the composites increased with increase in CNF composition. Overall, this work demonstrates industrially viable manufacturing processes to fabricate high performance PA 6/CNF nanocomposites.
Research on the Correlation between Work Accidents and Safety Policies in China
Authors: Wang Xiangbing , Wei Chengmin , He Yonghang , Zhang Hui , Wang Qifei
Published: May 2021

In China, safety policies interfere with the occurrence of work accidents in the form of guidance and restrictions. In this study, the impact of types of safety policies on work accident prevention is quantitatively analyzed. Based on a statistical analysis of China’s safety policies and work-related accidents from 2000 to 2020, the following four policy indexes that reflect the impact of safety policies are identified: the stringency level of the policy; the scope; its technical content; and its industrial target. A vector autoregressive model (VAR) is used, and a dynamic analysis of the model is conducted with an impulse response function. The model’s degree of fit is 92.9%, the number of deaths and the number of safety policies are linearly related, and the relative error between the fitted values and the real values is approximately 5%. The negative correlation between the death rate per 100 million yuan and the stringency level, scope, technical content, and industrial targets of safety policies is first weak, then strengthened, and then weakens again over time. This study finds that the importance of safety policy indicators is different; especially, the strict safety policy has a long-term negative impact on mortality. For developing countries such as China, where the safety policy system is not yet perfect, increasing the number and implementation of safety policies can significantly improve the situation of production safety.
Changes in the Greenness of Mountain Pine (Pinus mugo Turra) in the Subalpine Zone Related to the Winter Climate
Authors: Lukasová Veronika , Bucha Tomáš , Mareková Ľubica , Buchholcerová Anna , Bičárová Svetlana
Published: May 2021

In the current alteration of temperature and snow cover regimes, the impacts of winter climate have received considerably less attention than those of the vegetation period. In this study, we present the results demonstrating the influence of the winter climate conditions on the Mountain pine (Pinus mugo Turra) communities in High Tatra Mts (Western Carpathians). The changes in greenness in 2000–2020 were represented by the inter-annual differences of satellite-derived Normalized Difference Vegetation Index (NDVI). The winter climate conditions were characterized by climate indices calculated from the temperature and snow cover data measured at Skalnaté Pleso Observatory (1778 m a.s.l.) over the period between 1941–2020. Areas with P. mugo were classified into two density classes and five altitudinal zones of occurrence. The partial correlation analyses, which controlled the influence of summer climate, indicated that winter warm spells (WWS) caused a significant decrease in the greenness of the P. mugo thickets growing in the dense class D2 (R = −0.47) and in the altitudinal zones A2 (1600–1700 m a.s.l.) and A3 (1700–1800 m a.s.l.) with R = −0.54 for each zone. The changes in greenness were related to the average snow depth (ASD) as well, particularly in the dense class D2 (R = 0.45) and in the altitudinal zone A2 (R = 0.50). Here, in the summers following winters with the incidence of WWS or low ASD, we found decreased greenness following the injury of P. mugo shrubs, but NDVI after winters with higher ASD indicated more greenness. At lower altitudes, injuries may result in the loss of competition capacity of P. mugo near the timberline, where taller mountain tree species can utilize the conditions of warmer climate for expansion. We also found a significant positive effect of warmer winter seasons in the sparse P. mugo thickets (D1) with R = 0.50 and at higher altitudes (R = 0.49 in A4—1800–1900 m a.s.l.; R = 0.53 in A5—1900–2000 m a.s.l.). The increased temperatures in December correlated significantly with the increase of the greenness in all P. mugo pixels (R = 0.47), with the most pronounced effect in the sparse class D1 (R = 0.57) and in altitudinal zones A4 (R = 0.63) and A5 (R = 0.44), creating advantageous conditions for the thermophilisation of the alpine zone by P. mugo.
Inverting COSMIC-2 Phase Data to Bending Angle and Refractivity Profiles Using the Full Spectrum Inversion Method
Authors: Adhikari Loknath , Ho Shu-Peng , Zhou Xinjia
Published: May 2021

The radio occultation technique provides stable atmospheric measurements that can work as a benchmark for calibrating and validating satellite-sounding data. Launched on 25 June 2019, the Constellation Observing System for Meteorology, Ionosphere, and Climate 2 and Formosa Satellite Mission 7 (COSMIC-2/FORMOSAT-7) are expected to produce about 5000 high-quality RO observations daily over the tropics and subtropics. COSMIC-2 constellation consists of 6 Low Earth Orbit (LEO) satellites in 24° inclination orbits at 720 km altitude and distributed mainly between 45°N to 45°S. The COSMIC-2 observations have uniform temporal coverage between 30°N to 30°S. This paper presents an independent inversion algorithm to invert COSMIC-2 geometry and phase data to bending angle and refractivity. We also investigate the quality of Global Navigation Satellite System (GNSS) and LEO position vectors derived from the UCAR COSMIC Data Analysis and Archive Center (CDAAC). The GNSS and LEO position vectors are stable with LEO position variations < 1.4 mm/s. The signal-to-noise ratio (SNR) on the L1 band ranges from 300–2600 v/v with a mean of 1600 v/v. The inversion algorithm developed at NOAA Center for Satellite Applications and Research (STAR) uses the Full Spectrum Inversion (FSI) method to invert COSMIC-2 geometry and phase data to bending angle and refractivity profiles. The STAR COSMIC-2 bending angle and refractivity profiles are compared with in situ radiosonde, the current COSMIC-2 products derived from CDAAC, and the collocated European Center for Medium-Range Weather Forecasts (ECMWF) climate reanalysis data ERA5. The mean bias at 8–40 km altitude among the UCAR, ERA5, and STAR is <0.1% for both bending and refractivity, with a standard deviation in the range of 1.4–2.3 and 0.9–1.1% for bending angles refractivity, respectively. In the lowest 2 km, the RO bias relative to ERA-5 shows a strong latitudinal and SNR dependence.
Erratum: Yin et al. Remote Sensing of Atmospheric Hydrogen Fluoride (HF) over Hefei, China with Ground-Based High-Resolution Fourier Transform Infrared (FTIR) Spectrometry. Remote Sens. 2021, 13, 791
Authors: Yin Hao , Sun Youwen , Liu Cheng , Wang Wei , Shan Changgong , Zha Lingling
Published: May 2021

The authors would like to make the following correction of Authorship, Author Contributions and Acknowledgment [...]
A Performance Evaluation of Vis/NIR Hyperspectral Imaging to Predict Curcumin Concentration in Fresh Turmeric Rhizomes
Authors: Farrar Michael B. , Wallace Helen M. , Brooks Peter , Yule Catherine M. , Tahmasbian Iman , Dunn Peter K. , Hosseini Bai Shahla
Published: May 2021

Hyperspectral image (HSI) analysis has the potential to estimate organic compounds in plants and foods. Curcumin is an important compound used to treat a range of medical conditions. Therefore, a method to rapidly determine rhizomes with high curcumin content on-farm would be of significant advantage for farmers. Curcumin content of rhizomes varies within, and between varieties but current chemical analysis methods are expensive and time consuming. This study compared curcumin in three turmeric (Curcuma longa) varieties and examined the potential for laboratory-based HSI to rapidly predict curcumin using the visible–near infrared (400–1000 nm) spectrum. Hyperspectral images (n = 152) of the fresh rhizome outer-skin and flesh were captured, using three local varieties (yellow, orange, and red). Distribution of curcuminoids and total curcumin was analysed. Partial least squares regression (PLSR) models were developed to predict total curcumin concentrations. Total curcumin and the proportion of three curcuminoids differed significantly among all varieties. Red turmeric had the highest total curcumin concentration (0.83 ± 0.21%) compared with orange (0.37 ± 0.12%) and yellow (0.02 ± 0.02%). PLSR models predicted curcumin using raw spectra of rhizome flesh and pooled data for all three varieties (R2c = 0.83, R2p = 0.55, ratio of prediction to deviation (RPD) = 1.51) and was slightly improved by using images of a single variety (orange) only (R2c = 0.85, R2p = 0.62, RPD = 1.65). However, prediction of curcumin using outer-skin of rhizomes was poor (R2c = 0.64, R2p = 0.37, RPD = 1.28). These models can discriminate between ‘low’ and ‘high’ values and so may be adapted into a two-level grading system. HSI has the potential to help identify turmeric rhizomes with high curcumin concentrations and allow for more efficient refinement into curcumin for medicinal purposes.