bluuebunny/crossref_metadata_2025 huggingface dataset:
3D Printed Microfluidic Spiral Separation Device for Continuous, Pulsation-Free and Controllable CHO Cell Retention
Authors: Enders Anton , Preuss John-Alexander , Bahnemann Janina
Published: September 2021

The development of continuous bioprocesses—which require cell retention systems in order to enable longer cultivation durations—is a primary focus in the field of modern process development. The flow environment of microfluidic systems enables the granular manipulation of particles (to allow for greater focusing in specific channel regions), which in turn facilitates the development of small continuous cell separation systems. However, previously published systems did not allow for separation control. Additionally, the focusing effect of these systems requires constant, pulsation-free flow for optimal operation, which cannot be achieved using ordinary peristaltic pumps. As described in this paper, a 3D printed cell separation spiral for CHO-K1 (Chinese hamster ovary) cells was developed and evaluated optically and with cell experiments. It demonstrated a high separation efficiency of over 95% at up to 20 × 106 cells mL−1. Control over inlet and outlet flow rates allowed the operator to adjust the separation efficiency of the device while in use—thereby enabling fine control over cell concentration in the attached bioreactors. In addition, miniaturized 3D printed buffer devices were developed that can be easily attached directly to the separation unit for usage with peristaltic pumps while simultaneously almost eradicating pump pulsations. These custom pulsation dampeners were closely integrated with the separator spiral lowering the overall dead volume of the system. The entire device can be flexibly connected directly to bioreactors, allowing continuous, pulsation-free cell retention and process operation.
A Magnetic Geothermometer in Moderately Buried Shales
Authors: Aubourg Charles , Kars Myriam , Pozzi Jean-Pierre , Mazurek Martin , Grauby Olivier
Published: September 2021

Shales contain magnetic minerals generally at very low concentrations. In the early stages of diagenesis, the inherited magnetic minerals are altered, while magnetic nanominerals are formed. In this study, we proposed a study of shales over a stratigraphic thickness of 1.3 km from a borehole in the Paris basin (Borehole EST 433, France), and shales from the same formation (Opalinus Clay) collected in seven boreholes in the Jura molasse basin (Swiss). Magnetic measurements at experimental temperatures <30 K allowed the formation of a proxy of magnetite nanograins named PM. We showed that some of these nanograins formed around the pyrite grains, probably under the action of temperature and organic matter. PM was then compared to the maturity values of the organic matter. We found a correlation between PM and the percentage of reflectance of vitrinite. The shales from both Paris and molassic Swiss basins showed very comparable magnetic characteristics for a given maturity level. The magnetic study therefore provided constraints on the maturity level of the shales in the oil window area. Our study showed that PM can be used as a geothermometer in shales in which CaCO3 is lower than 60%.
Hyper-Cross-Linked Polystyrene as a Stabilizing Medium for Small Metal Clusters
Authors: Bykov Alexey V. , Demidenko Galina N. , Nikoshvili Linda Zh. , Kiwi-Minsker Lioubov
Published: September 2021

Among different polymers nanostructured cross-linked aromatics have the greatest potential as catalytic supports due to their exceptional thermal and chemical stability and preservation of the active phase morphology. This work studies the ability of hyper-cross-linked polystyrene (HPS) to stabilize small Pdn and Ptn (n = 4 or 9) clusters. Unrestricted DFT calculations were carried out for benzene (BZ) adsorption at the BP level of theory using triple-zeta basis sets. The adsorption of BZ rings (stepwise from one to four) was found to result in noticeable gain in energy and stabilization of resulting adsorption complexes. Moreover, the interaction of metal clusters with HPS micropores was also addressed. For the first time, the incorporation of small clusters in the HPS structure was shown to influences its geometry resulting in the stabilization of polymer due to its partial relaxation.
Conjugated β-Cyclodextrin Enhances the Affinity of Folic Acid towards FRα: Molecular Dynamics Study
Authors: Al-Thiabat Mohammad G. , Gazzali Amirah Mohd , Mohtar Noratiqah , Murugaiyah Vikneswaran , Kamarulzaman Ezatul Ezleen , Yap Beow Keat , Rahman Noorsaadah Abd , Othman Rozana , Wahab Habibah A.
Published: September 2021

Drug targeting is a progressive area of research with folate receptor alpha (FRα) receiving significant attention as a biological marker in cancer drug delivery. The binding affinity of folic acid (FA) to the FRα active site provides a basis for recognition of FRα. In this study, FA was conjugated to beta-cyclodextrin (βCD) and subjected to in silico analysis (molecular docking and molecular dynamics (MD) simulation (100 ns)) to investigate the affinity and stability for the conjugated system compared to unconjugated and apo systems (ligand free). Docking studies revealed that the conjugated FA bound into the active site of FRα with a docking score (free binding energy < −15 kcal/mol), with a similar binding pose to that of unconjugated FA. Subsequent analyses from molecular dynamics (MD) simulations, root mean square deviation (RMSD), root mean square fluctuation (RMSF), and radius of gyration (Rg) demonstrated that FA and FA–βCDs created more dynamically stable systems with FRα than the apo-FRα system. All systems reached equilibrium with stable RMSD values ranging from 1.9–2.4 Å and the average residual fluctuation values of the FRα backbone atoms for all residues (except for terminal residues ARG8, THR9, THR214, and LEU215) were less than 2.1 Å with a consistent Rg value of around 16.8 Å throughout the MD simulation time (0–100 ns). The conjugation with βCD improved the stability and decreased the mobility of all the residues (except residues 149–151) compared to FA–FRα and apo-FRα systems. Further analysis of H-bonds, binding free energy (MM-PBSA), and per residue decomposition energy revealed that besides APS81, residues HIS20, TRP102, HIS135, TRP138, TRP140, and TRP171 were shown to have more favourable energy contributions in the holo systems than in the apo-FRα system, and these residues might have a direct role in increasing the stability of holo systems.
Novel Antiretroviral Therapeutic Strategies for HIV
Authors: Cunha Rita F. , Simões Sandra , Carvalheiro Manuela , Pereira José M. Azevedo , Costa Quirina , Ascenso Andreia
Published: September 2021

When the first cases of HIV infection appeared in the 1980s, AIDS was a deadly disease without any therapeutic alternatives. Currently, there is still no cure for most cases mainly due to the multiple tissues that act as a reservoir for this virus besides the high viral mutagenesis that leads to an antiretroviral drug resistance. Throughout the years, multiple drugs with specific mechanisms of action on distinct targets have been approved. In this review, the most recent phase III clinical studies and other research therapies as advanced antiretroviral nanodelivery systems will be here discussed. Although the combined antiretroviral therapy is effective in reducing viral loading to undetectable levels, it also presents some disadvantages, such as usual side effects, high frequency of administration, and the possibility of drug resistance. Therefore, several new drugs, delivery systems, and vaccines have been tested in pre-clinical and clinical trials. Regarding drug delivery, an attempt to change the route of administration of some conventional antiretrovirals has proven to be successful and surpassed some issues related to patient compliance. Nanotechnology has brought a new approach to overcoming certain obstacles of formulation design including drug solubility and biodistribution. Overall, the encapsulation of antiretroviral drugs into nanosystems has shown improved drug release and pharmacokinetic profile.
Seaweed-Based Molecules and Their Potential Biological Activities: An Eco-Sustainable Cosmetics
Authors: Kalasariya Haresh S. , Yadav Virendra Kumar , Yadav Krishna Kumar , Tirth Vineet , Algahtani Ali , Islam Saiful , Gupta Neha , Jeon Byong-Hun
Published: September 2021

Amongst the countless marine organisms, seaweeds are considered as one of the richest sources of biologically active ingredients having powerful biological activities. Seaweeds or marine macroalgae are macroscopic multicellular eukaryotic photosynthetic organisms and have the potential to produce a large number of valuable compounds, such as proteins, carbohydrates, fatty acids, amino acids, phenolic compounds, pigments, etc. Since it is a prominent source of bioactive constituents, it finds diversified industrial applications viz food and dairy, pharmaceuticals, medicinal, cosmeceutical, nutraceutical, etc. Moreover, seaweed-based cosmetic products are risen up in their demands by the consumers, as they see them as a promising alternative to synthetic cosmetics. Normally it contains purified biologically active compounds or extracts with several compounds. Several seaweed ingredients that are useful in cosmeceuticals are known to be effective alternatives with significant benefits. Many seaweeds’ species demonstrated skin beneficial activities, such as antioxidant, anti-melanogenesis, antiaging, photoprotection, anti-wrinkle, moisturizer, antioxidant, anti-inflammatory, anticancer and antioxidant properties, as well as certain antimicrobial activities, such as antibacterial, antifungal and antiviral activities. This review presents applications of bioactive molecules derived from marine algae as a potential substitute for its current applications in the cosmetic industry. The biological activities of carbohydrates, proteins, phenolic compounds and pigments are discussed as safe sources of ingredients for the consumer and cosmetic industry.
Immersive Virtual Reality Exergame Promotes the Practice of Physical Activity in Older People: An Opportunity during COVID-19
Authors: Campo-Prieto Pablo , Rodríguez-Fuentes Gustavo , Cancela-Carral José Mª
Published: September 2021

Life expectancy has increased in recent years. Physical activity has been postulated as a key element in active aging strategies. However, adherence to physical exercise programs has traditionally been low among the elderly, and the current situation of the COVID-19 pandemic has added extra impediments. Immersive virtual reality (IVR) devices could motivate this population to practice exercise. This study aimed to analyse the use of IVR exergames as a tool to facilitate physical exercise in older people. Four healthy older adults (males, 65–77 years) participated in the study. They carried out two exergaming sessions with HTC Vive ProTM. Outcomes were evaluated using the Simulator Sickness Questionnaire (SSQ), System Usability Scale (SUS), Game Experience Questionnaire (GEQ post-game module), an ad hoc satisfaction questionnaire, and perceived effort. All participants completed the sessions without adverse effects, with no SSQ symptoms reported. SUS scores were high in both sessions (SUS > 85/100). Post-game GEQ scores were 3.08–3.41/4 (positive experiences) and 0.08–0.16/4 (negative experiences). Opinions showed high levels of satisfaction with the experience. Exergaming programs, based on commercial head-mounted displays, are a feasible alternative to traditional senior exercise, and could be a solution to the current situation that has arisen from the impact of the COVID-19 pandemic.
Low Toxicological Impact of Commercial Pristine Multi-Walled Carbon Nanotubes on the Yeast Saccharomyces cerevisiae
Authors: Martel Martín Sonia , Barros Rocío , Domi Brixhilda , Rumbo Carlos , Poddighe Matteo , Aparicio Santiago , Suarez-Diez Maria , Tamayo-Ramos Juan Antonio
Published: September 2021

Carbon nanotubes (CNTs) have attracted the attention of academy and industry due to their potential applications, being currently produced and commercialized at a mass scale, but their possible impact on different biological systems remains unclear. In the present work, an assessment to understand the toxicity of commercial pristine multi-walled carbon nanotubes (MWCNTs) on the unicellular fungal model Saccharomyces cerevisiae is presented. Firstly, the nanomaterial was physico-chemically characterized, to obtain insights concerning its morphological features and elemental composition. Afterwards, a toxicology assessment was carried out, where it could be observed that cell proliferation was negatively affected only in the presence of 800 mg L−1 for 24 h, while oxidative stress was induced at a lower concentration (160 mg L−1) after a short exposure period (2 h). Finally, to identify possible toxicity pathways induced by the selected MWCNTs, the transcriptome of S. cerevisiae exposed to 160 and 800 mg L−1, for two hours, was studied. In contrast to a previous study, reporting massive transcriptional changes when yeast cells were exposed to graphene nanoplatelets in the same exposure conditions, only a small number of genes (130) showed significant transcriptional changes in the presence of MWCNTs, in the higher concentration tested (800 mg L−1), and most of them were found to be downregulated, indicating a limited biological response of the yeast cells exposed to the selected pristine commercial CNTs.
The Electromagnetic Will
Authors: McFadden Johnjoe
Published: September 2021

The conscious electromagnetic information (cemi) field theory proposes that the seat of consciousness is the brain’s electromagnetic (EM) field that integrates information from trillions of firing neurons. What we call free will is its output. The cemi theory also proposes that the brain has two streams. Most actions are initiated by the first non-conscious stream that is composed of neurons that are insulated from EM field influences. These non-conscious involuntary actions are thereby invisible to our EM field-located thoughts. The theory also proposes that voluntary actions are driven by neurons that receive EM field inputs and are thereby visible to our EM field-located thoughts. I review the extensive evidence for EM field/ephaptic coupling between neurons and the increasing evidence that EM fields in the brain are a cause of behaviour. I conclude by arguing that though this EM field-driven will is not free, in the sense of being acausal, it nevertheless corresponds to the very real experience of our conscious mind being in control of our voluntary actions. Will is not an illusion. It is our experience of control by our EM field-located mind. It is an immaterial, yet physical, will.
Kidney Function-Dependence of Vitamin K-Status Parameters: Results from the TransplantLines Biobank and Cohort Studies
Authors: Kremer Daan , Groothof Dion , Keyzer Charlotte A. , Eelderink Coby , Knobbe Tim J. , Post Adrian , van Londen Marco , Eisenga Michele F. , TransplantLines Investigators  , Schurgers Leon J. , Berger Stefan P. , de Borst Martin H. , Bakker Stephan J. L.
Published: September 2021

High circulating dephosphorylated (dp) uncarboxylated (uc) matrix Gla protein (MGP) and uc osteocalcin (OC) concentrations are regarded as markers of vitamin K-deficiency. However, because MGP and OC are small molecules, they may potentially pass the glomerulus, and their blood concentrations may strongly depend on kidney function. However, many studies with vitamin K-status parameters do not structurally adjust for baseline kidney function, and detailed studies on kidney function-dependence of vitamin K-status markers are lacking. We therefore measured plasma dp-ucMGP using a chemiluminescent assay in 578 kidney transplant recipients (41% females, age 56 ± 13y, 7.5 (3.2 to 13.7)y after transplantation, eGFR 49 ± 17 mL/min/1.73 m2) participating in the prospective TransplantLines Cohort Studies. Additionally, dp-carboxylated MGP, ucOC and carboxylated OC were measured using ELISA in plasma of a subgroup of 60 participants. Finally, dp-ucMGP was measured in a separate cohort of 124 kidney transplant recipients before and three months after kidney transplantation. Dp-ucMGP positively correlated with creatinine, cystatin C, and negatively with eGFR (Spearman’s ρ 0.54, 0.60, and −0.54, respectively, p < 0.001 for all), and each 10 mL/min/1.73 m2 increase in eGFR was associated with a 14.0% lower dp-ucMGP. Additionally, dp-ucMGP strongly declined after kidney transplantation (pretransplantation: 1252 (868 to 1744) pmol/L to posttransplantation: 609 (451 to 914) pmol/L, p < 0.001). Proportions of dp-ucMGP over total MGP and ucOC over total OC were not associated with eGFR. This study highlights that dp-ucMGP is strongly associated with kidney function, and that levels strongly decrease after kidney transplantation. We therefore propose adequate adjustment for kidney function, or the use of kidney function-independent parameters such as proportion of uncarboxylated MGP or OC in the assessment of vitamin K-status in clinical practice and research.
Empowering Public Health Nurses and Community Home Visitors through Effective Communication Relationships
Authors: Sheppard-LeMoine Debbie , Aston Megan , Goldberg Lisa , MacDonald Judy , Tamlyn Deb
Published: September 2021

Home visiting programs for marginalized families have included both Public Health Nurses (PHNs) and Community Home Visitors (CHV). Support for families requires health care providers to implement effective communication and collaboration practices; however, few studies have examined how this is carried out. The purpose of this qualitative research study was to explore how an Enhanced Home Visiting (EHV) program in Nova Scotia Canada was organized, delivered through the experiences of PHNs and CHVs. Feminist post-structuralism informed by discourse analysis was used to understand how their experiences were socially and institutionally constructed. Individual semi-structured interviews were conducted with 6 PHNs and 8 CHVs and one focus group was held with 10 of the participants. A social discourse on mothering layered within a social discourse of working with a vulnerable population added a deeper understanding of how communication was constructed through the everyday practices of PHNs and CHVs. Findings may be used to inform reporting and communication practices between health care providers who work with marginalized families.
Micro-Epidemiological Investigation of Echinococcus multilocularis in Wild Hosts from an Endemic Area of Southwestern Hungary
Authors: Halász Tibor , Nagy Gábor , Nagy István , Csivincsik Ágnes
Published: September 2021

Echinococcus multilocularis is a tapeworm causing severe zoonotic disease in temperate Europe. Between 2018 and 2020, 68 golden jackals and 94 red foxes were investigated to determine the prevalence of E. multilocularis infection and its driving factors. The overall prevalence (golden jackal: 41.2%; red fox: 12.5%) significantly differed, whereas the mean intensities did not. The spatial scan statistics revealed three significant clusters of E. multilocularis infection. The binary logistic and ordinal regression results revealed that the golden jackal is more likely to become infected than the red fox, and the probability of infection level was also higher in jackals. Our findings highlight the golden jackal’s role, which could be as important as the red fox in the spread of this severe zoonotic agent. This micro-epidemiological approach can advance the knowledge on local drivers which facilitate the spread of E. multilocularis and could cause a relevant public health problem on the continent.
Acute Hepatitis B and Unusual Follow-Up in a 16-Year-Old Boy: Case Report
Authors: Bieńkowski Carlo , Kowalczyk Monika , Pluta Magdalena , Pokorska-Śpiewak Maria
Published: September 2021

In this case report, we present a 16-year-old Ukrainian boy with acute hepatitis B. He had not been previously vaccinated against hepatitis B. Possible sources of infection included: a tattoo made at home, a finger cut made with hairdresser scissors during work, and unprotected sexual encounters. The clinical course of the disease was typical with jaundice and elevated aminotransferases levels without liver failure. During the follow-up visit 16 months after the onset of the disease, chronic hepatitis b was excluded but an ulcer around his anus was found. Additional tests for sexually transmitted diseases were ordered and they were positive for syphilis. The extended interview revealed that the patient had several unprotected bisexual encounters, which may have indicated a potential source of infections including the hepatitis B virus (HBV). The reported case shows that despite the significant decrease in the hepatitis B prevalence in Poland, the infection is still possible. It is necessary to conduct epidemiological interviews regarding sexually transmitted diseases in teenagers, especially when a blood-borne disease has been diagnosed.
Metformin a Potential Pharmacological Strategy in Late Onset Alzheimer’s Disease Treatment
Authors: Poor Saghar Rabiei , Ettcheto Miren , Cano Amanda , Sanchez-Lopez Elena , Manzine Patricia Regina , Olloquequi Jordi , Camins Antoni , Javan Mohammad
Published: September 2021

Alzheimer’s disease (AD) is one of the most devastating brain disorders. Currently, there are no effective treatments to stop the disease progression and it is becoming a major public health concern. Several risk factors are involved in the progression of AD, modifying neuronal circuits and brain cognition, and eventually leading to neuronal death. Among them, obesity and type 2 diabetes mellitus (T2DM) have attracted increasing attention, since brain insulin resistance can contribute to neurodegeneration. Consequently, AD has been referred to “type 3 diabetes” and antidiabetic medications such as intranasal insulin, glitazones, metformin or liraglutide are being tested as possible alternatives. Metformin, a first line antihyperglycemic medication, is a 5′-adenosine monophosphate (AMP)-activated protein kinase (AMPK) activator hypothesized to act as a geroprotective agent. However, studies on its association with age-related cognitive decline have shown controversial results with positive and negative findings. In spite of this, metformin shows positive benefits such as anti-inflammatory effects, accelerated neurogenesis, strengthened memory, and prolonged life expectancy. Moreover, it has been recently demonstrated that metformin enhances synaptophysin, sirtuin-1, AMPK, and brain-derived neuronal factor (BDNF) immunoreactivity, which are essential markers of plasticity. The present review discusses the numerous studies which have explored (1) the neuropathological hallmarks of AD, (2) association of type 2 diabetes with AD, and (3) the potential therapeutic effects of metformin on AD and preclinical models.
Microencapsulated Chitosan-Based Nanocapsules: A New Platform for Pulmonary Gene Delivery
Authors: Fernández-Paz Estefanía , Feijoo-Siota Lucía , Gaspar Maria Manuela , Csaba Noemi , Remuñán-López Carmen
Published: September 2021

In this work, we propose chitosan (CS)-based nanocapsules (NCs) for pulmonary gene delivery. Hyaluronic acid (HA) was incorporated in the NCs composition (HA/CS NCs) aiming to promote gene transfection in the lung epithelium. NCs were loaded with a model plasmid (pCMV-βGal) to easily evaluate their transfection capacity. The plasmid encapsulation efficiencies were of approx. 90%. To facilitate their administration to the lungs, the plasmid-loaded NCs were microencapsulated in mannitol (Ma) microspheres (MS) using a simple spray-drying technique, obtaining dry powders of adequate properties. In vivo, the MS reached the deep lung, where the plasmid-loaded CS-based NCs were released and transfected the alveolar cells more homogeneously than the control formulation of plasmid directly microencapsulated in Ma MS. The HA-containing formulation achieved the highest transfection efficiency, in a more extended area and more homogeneously distributed than the rest of tested formulations. The new micro-nanostructured platform proposed in this work represents an efficient strategy for the delivery of genetic material to the lung, with great potential for the treatment of genetic lung diseases.
Dual Emissive Ir(III) Complexes for Photodynamic Therapy and Bioimaging
Authors: Redrado Marta , Benedi Andrea , Marzo Isabel , Gimeno M. Concepción , Fernández-Moreira Vanesa
Published: September 2021

Photodynamic therapy (PDT) is a cancer treatment still bearing enormous prospects of improvement. Within the toolbox of PDT, developing photosensitizers (PSs) that can specifically reach tumor cells and promote the generation of high concentration of reactive oxygen species (ROS) is a constant research goal. Mitochondria is known as a highly appealing target for PSs, thus being able to assess the biodistribution of the PSs prior to its light activation would be crucial for therapeutic maximization. Bifunctional Ir(III) complexes of the type [Ir(C^N)2(N^N-R)]+, where N^C is either phenylpyridine (ppy) or benzoquinoline (bzq), N^N is 2,2′-dipyridylamine (dpa) and R either anthracene (1 and 3) or acridine (2 and 4), have been developed as novel trackable PSs agents. Activation of the tracking or therapeutic function could be achieved specifically by irradiating the complex with a different light wavelength (405 nm vs. 470 nm respectively). Only complex 4 ([Ir(bzq)2(dpa-acr)]+) clearly showed dual emissive pattern, acridine based emission between 407–450 nm vs. Ir(III) based emission between 521 and 547 nm. The sensitivity of A549 lung cancer cells to 4 evidenced the importance of involving the metal center within the activation process of the PS, reaching values of photosensitivity over 110 times higher than in dark conditions. Moreover, complex 4 promoted apoptotic cell death and possibly the paraptotic pathway, as well as higher ROS generation under irradiation than in dark conditions. Complexes 2–4 accumulated in the mitochondria but species 2 and 4 also localizes in other subcellular organelles.
Advances in Ocular Drug Delivery Systems
Authors: Silva-Cunha Armando
Published: September 2021

There have been major advances in the treatment of eye diseases over the last years [...]
Ex Vivo Determination of Broadband Absorption and Effective Scattering Coefficients of Porcine Tissue
Authors: Bergmann Florian , Foschum Florian , Marzel Leonie , Kienle Alwin
Published: September 2021

A novel approach for precise determination of the optical scattering and absorption properties of porcine tissue using an optimized integrating sphere setup was applied. Measurements on several sample types (skin, muscle, adipose tissue, bone, cartilage, brain) in the spectral range between 400 nm and 1400 nm were performed. Due to the heterogeneity of biological samples, measurements on different individual animals as well as on different sections for each sample type were carried out. For all samples, we used an index matching method to reduce surface roughness effects and to prevent dehydration. The derived absorption spectra were used to estimate the concentration of important tissue chromophores such as water, oxy- and deoxyhemoglobin, collagen and fat.
Inhalation Exposure to PCB from Contaminated Indoor Air—How Much Is Absorbed into the Blood?
Authors: Kraft Martin , Rauchfuss Knut , Fromme Hermann , Grün Lothar , Sievering Silvia , Köllner Barbara , Chovolou Yvonni
Published: September 2021

Polychlorinated biphenyls (PCBs) were used in many construction products until their banning in the 1970s and 1980s. Nonetheless, exposure to PCBs from contaminated indoor air is still an important public health issue. The aim of our study was to estimate the contribution of PCB congeners in indoor air to the levels of PCBs in human blood. We analyzed all 209 PCB congeners in the blood of 35 individuals exposed to PCBs from contaminated indoor air. For each individual, we measured the six marker indicators PCB28, PCB52, PCB101, PCB138, PCB153 and PCB180 in indoor air at the workplace. Statistically significant correlations between PCB-contaminated indoor air and the existence of the sum of mono-, di-, tri-, tetra- and pentachlorinated biphenyls (∑PCB1–127) in the blood of the exposed individuals were found. We quantified the proportions of PCBs that are absorbed into the blood via inhalation of contaminated indoor air. Inhalation of PCBs from contaminated indoor air, especially in children, adolescents and younger adults, may lead to PCB blood burdens that are higher than general PCB background levels or in approximately the same range.
Comparison of Three Interfacial Conductive Networks Formed in Carbon Black-Filled PA6/PBT Blends
Authors: Li Hansong , Tuo Xinlin , Guo Bao-Hua , Yu Jian , Guo Zhao-Xia
Published: September 2021

Interfacial localization of carbon fillers in cocontinuous-structured polymer blends is well-known as a high-efficiency strategy for conductive network formation. However, a comparison with interfacial localization of carbon fillers in sea-island-structured polymer blends is lacking. Here, three types of highly efficient conductive networks formed on the basis of interfacial localization of carbon black (CB) in polyamide 6 (PA6)/poly(butylene terephthalate) (PBT) blends with different blend compositions (80/20, 50/50 and 20/80 vol/vol) were investigated and compared in terms of electrical resistivity, morphology as well as rheological and mechanical properties. The order of the electrical percolation threshold of CB in the three blends is 50/50 < 20/80 < 80/20, which can be attributed to different network structures. The rheological percolation thresholds are close to the electrical ones, confirming the formation of CB networks. The formation mechanisms for the three types of CB network structures are analyzed. All the three types of PA6/PBT-6 vol% CB composites showed improved tensile strength compared with PA6/PBT blends, being in favor for practical applications.
Preparation and Properties of Self-Healing Waterborne Polyurethane Based on Dynamic Disulfide Bond
Authors: Ye Gongbo , Jiang Tao
Published: September 2021

A self-healing waterborne polyurethane (WPU) materials containing dynamic disulfide (SS) bond was prepared by introducing SS bond into polymer materials. The zeta potential revealed that all the synthesized WPU emulsions displayed excellent stability, and the particle size of them was about 100 nm. The characteristic peaks of N-H and S-S in urethane were verified by FTIR, and the chemical environment of all elements were confirmed by the XPS test. Furthermore, the tensile strength, self-healing process and self-healing efficiency of the materials were quantitatively evaluated by tensile measurements. The results showed that the self-healing efficiency could reach 96.14% when the sample was heat treated at 70 °C for 4 h. In addition, the material also showed a good reprocessing performance, and the tensile strength of the reprocessed film was 3.39 MPa.
Symmetry-Breaking Drop Bouncing on Superhydrophobic Surfaces with Continuously Changing Curvatures
Authors: Choi WooSeok , Yun Sungchan
Published: September 2021

Controlling the residence time of drops on the solid surface is related to a wide spectrum of engineering applications, such as self-cleaning and anti-icing. The symmetry-breaking dynamics induced by the initial drop shape can promote drop bouncing. Here, we study the bouncing features of spherical and ellipsoidal drops on elliptical surfaces that continuously change curvatures inspired by natural succulent leaves. The bounce characteristics highly depend on the geometric relations between the ellipsoidal drops and curved surfaces. Numerical results show that ellipsoidal shapes of the drops amplify asymmetries of the mass and momentum in synergy with an influence of the surface curvature during the impact, which is verified by experiments. Effects of the surface anisotropy and drops’ ellipticity on the residence time are investigated under various surface morphologies and Weber numbers. The residence time is closely associated with an initial surface curvature at the apex. The underlying principle of modifying the residence time via the drops’ ellipticity and initial surface curvature is elucidated based on momentum asymmetry. The understanding of the bouncing features on curved surfaces will offer practical implications for enhanced heat transfer performances and controlled water repellency, etc.
Electrical Property of Polypropylene Films Subjected to Different Temperatures and DC Electric Fields
Authors: Zhang Chuyan , Shi Weichen , Wang Qiao , Diao Mingguang , Hiziroglu Huseyin R.
Published: September 2021

A polypropylene (PP) film is usually used as a dielectric material in capacitors as well as cables. However, PP films may degrade because of the combined effect of temperature and electric field. In an earlier study, plain PP films and PP films loaded with nano-metric natural clay were studied under sinusoidal (AC) electric fields at power frequency and temperatures above the ambient. To better understand the electrical characteristics of PP film under various conditions, the objective of this study is to determine the time-to-breakdown of the plain PP and PP filled with 2% (wt) natural nano-clay when subjected to time-invariant (DC) electric fields at elevated temperatures. In order to achieve this objective, the effects of uniform as well as non-uniform electric fields were compared at the same temperature for the PP film. In this study, experimental results indicated that the time-to-breakdown of all PP films, plain or filled with nano-clay, decreases with the increase in electric field intensity, non-uniformity of the electric field, and temperature. It was also found that the time-to-breakdown of PP film filled with 2% (wt) natural nano-clay under DC electric field is longer and less sensitive to temperature. Furthermore, when compared with the results under the uniform electric field, PP film filled with 2% (wt) nano-metric natural clay indicates shorter time-to-failure under non-uniform DC electric fields. Finally, the morphology of the samples was observed by digital camera, optical micrography, and SEM, to better understand the mechanism of the breakdown.
Nano-Second Laser Interference Photoembossed Microstructures for Enhanced Cell Alignment
Authors: Martínez Alba , González-Lana Sandra , Asín Laura , de la Fuente Jesús M. , Bastiaansen Cees W. M. , Broer Dirk J. , Sánchez-Somolinos Carlos
Published: September 2021

Photoembossing is a powerful photolithographic technique to prepare surface relief structures relying on polymerization-induced diffusion in a solventless development step. Conveniently, surface patterns are formed by two or more interfering laser beams without the need for a lithographic mask. The use of nanosecond pulsed light-based interference lithography strengthens the pattern resolution through the absence of vibrational line pattern distortions. Typically, a conventional photoembossing protocol consists of an exposure step at room temperature that is followed by a thermal development step at high temperature. In this work, we explore the possibility to perform the pulsed holographic exposure directly at the development temperature. The surface relief structures generated using this modified photoembossing protocol are compared with those generated using the conventional one. Importantly, the enhancement of surface relief height has been observed by exposing the samples directly at the development temperature, reaching approximately double relief heights when compared to samples obtained using the conventional protocol. Advantageously, the light dose needed to reach the optimum height and the amount of photoinitiator can be substantially reduced in this modified protocol, demonstrating it to be a more efficient process for surface relief generation in photopolymers. Kidney epithelial cell alignment studies on substrates with relief-height optimized structures generated using the two described protocols demonstrate improved cell alignment in samples generated with exposure directly at the development temperature, highlighting the relevance of the height enhancement reached by this method. Although cell alignment is well-known to be enhanced by increasing the relief height of the polymeric grating, our work demonstrates nano-second laser interference photoembossing as a powerful tool to easily prepare polymeric gratings with tunable topography in the range of interest for fundamental cell alignment studies.
Catalyst-Free Crosslinking Modification of Nata-de-Coco-Based Bacterial Cellulose Nanofibres Using Citric Acid for Biomedical Applications
Authors: Salihu Rabiu , Ansari Mohamed Nainar Mohamed , Abd Razak Saiful Izwan , Ahmad Zawawi Nurliyana , Shahir Shafinaz , Sani Mohd Helmi , Ramlee Muhammad Hanif , Wsoo Mohammed Ahmad , Mohd Yusof Abdul Halim , Nayan Nadirul Hasraf Mat , Gumel Ahmad Mohammed
Published: September 2021

Bacterial cellulose (BC) has gained attention among researchers in materials science and bio-medicine due to its fascinating properties. However, BC’s fibre collapse phenomenon (i.e., its inability to reabsorb water after dehydration) is one of the drawbacks that limit its potential. To overcome this, a catalyst-free thermal crosslinking reaction was employed to modify BC using citric acid (CA) without compromising its biocompatibility. FTIR, XRD, SEM/EDX, TGA, and tensile analysis were carried out to evaluate the properties of the modified BC (MBC). The results confirm the fibre crosslinking phenomenon and the improvement of some properties that could be advantageous for various applications. The modified nanofibre displayed an improved crystallinity and thermal stability with increased water absorption/swelling and tensile modulus. The MBC reported here can be used for wound dressings and tissue scaffolding.
Experimental Study on High-Performers Quaternary Copolymer Based on Host–Guest Effect
Authors: Xu Tao , Mao Jincheng , Zhang Yang , Yang Xiaojiang , Lin Chong , Du Anqi , Zhang Heng , Zhang Quan , Mao Jinhua
Published: September 2021

A quaternary polymer (HGP) was prepared by the free-radical polymerization of acrylamide, acrylic acid, maleic anhydride functionalized β-cyclodextrin (MAH-β-CD), and N-(3-methacrylamidopropyl)-N, N-dimethylnaphthalen-1-aminium chloride (NAP). It was found that host–guest behavior occurred most effectively at a molar rate of NAP and CD with 1:1, which exhibited better solubility than hydrophobically associative polymer. Moreover, the as-prepared polymer has superior salt tolerance, shear resistance, and viscoelasticity due to host–guest strategy. More importantly, the HGP solution simulates the distribution of formation water in the Bohai SZ1-1 oilfield has good rheological properties at 120 °C. All results show that the proposed polymer could be a competitive candidate in oilfield applications such as fracturing fluids, displacement fluids, and drilling fluids.
Electrochemical Study of Stainless Steel Anchor Bolt Corrosion Initiation in Corrosive Underground Water
Authors: Ma Fangping , Zeng Qing , Lu Xiangyu , Wu Tong , Lu Xiao , Zhang Tianyi , Feng Xingguo
Published: September 2021

Application of low-nickel stainless steel anchor was one of the economical and effective methods to solve the durability problem of slope engineering. At present, there are scarce reports about corrosion characteristics of low-nickel stainless steel in various underground waters. For investigating the corrosion initiation of stainless steel anchor bolt in corrosive underground water, the effect of SO42−, HCO3− and pH value on the corrosion behavior of 201 low-nickel stainless steel was studied via electrochemical methods. As the SO42− concentration, HCO3− concentration or pH value increase, the open circuit potential and polarization resistance increase, while the double-layer capacitance, donor density and passive current density decrease. The results indicate that corrosion is inhibited by SO42−, HCO3− and OH− in underground water. In addition, the inhibitive efficiency of SO42− and HCO3− increases with the SO42− and HCO3− concentration.
Clozapine and Constipation: A Review of Clinical Considerations and Treatment Options
Authors: Edinoff Amber N. , Sauce Emily , Ochoa Carolina O. , Cross Jordan , Cogburn Mark , Cornett Elyse M. , Kaye Adam M. , Pham Alex D. , Kaye Alan D.
Published: September 2021

Psychosis, a break in reality which is manifested as hallucinations, delusions or the disruption in thought process, is the hallmark of schizophrenia. Despite novel pharmacotherapy advancements of antipsychotic medications that have resulted in some patients having the ability to return to social settings and thereby decreasing psychotic symptoms and reducing hospital admissions, there is still a sub-population of patients who remain symptomatic. Treatment-resistant schizophrenia is defined as failure of treatment with at least two different antipsychotics with the proper length of treatment and titration. Clozapine has been heralded as a drug to resolve the puzzle of treatment-resistant schizophrenia. Clozapine has one side effect that is well known, being the development of agranulocytosis. However, there is another side effect that can limit clozapine’s use and can also be life-threatening. Recently, at the end of January 2020, the FDA issued a communications statement which “[strengthened] an existing warning that constipation caused by the schizophrenia medicine clozapine can, uncommonly, progress to serious bowel complications.” After identifying ten cases of constipation from between 2006 to 2016 that progressed to hospitalization, surgery, and even death, the FDA focused their attention on this often overlooked, common side effect, especially when considering the strong anticholinergic effects of clozapine. Although patients are screened by their physicians for agranulocytosis by weekly lab monitoring, constipation is also a complication that needs to be identified and treated. Much like opioid-induced constipation, constipation can also be reduced with the use of laxatives and reduction in the co-prescribing of anticholinergic therapies with clozapine.
Self-Compassion and Social Connectedness as Predictors of “Peace and Meaning” during Spain’s Initial COVID-19 Lockdown
Authors: Saiz Jesús , Ausín Berta , González-Sanguino Clara , Castellanos Miguel Ángel , Salazar María , Marin Carolina , López-Gómez Aída , Ugidos Carolina , Muñoz Manuel
Published: September 2021

The COVID-19 lockdown has had a massive psychological impact on mental health in the general population, with increases in anxiety, depression, and post-traumatic stress disorder. Spiritual well-being, specifically peace and meaning, has already been identified as one of the main protective factors for these disorders in the COVID-19 context. The aim of the present study is to identify facilitating elements for peace and meaning during the COVID-19 lockdown in Spain. Online surveys were used to obtain data from a sample of 3480 Spanish people. Self-compassion and social support were positively related with peace and meaning, while loneliness and perceived discrimination were negatively related. The model for peace and meaning was statistically significant, explaining 47% of the variance. The significant variables were self-kindness, family support, mindfulness, and sense of belonging having a positive association and loneliness a negative one.
Emerging Hindu Rashtra and Its Impact on Indian Muslims
Authors: Khan M. A. Muqtedar , Lutful Rifat Binte
Published: September 2021

This article examines the impact of the gradual Hindutvaization of Indian culture and politics on Indian Muslims. The article contrasts the status of Muslims in the still secular, pluralistic, and democratic constitution of India with the rather marginalized reality of Muslims since the rise of Hindu nationalism. The article argues that successive electoral victories by Hindu nationalist party, the Bharatiya Janata Party, has precipitated political events, generated policies, and passed new laws that are eroding the democratic nature of India and undermining its religious freedoms. The article documents recent changes that are expediting the emergence of the Hindu state in India and consequently exposes the world’s largest religious minority to an intolerant form of majoritarian governance.
Envisioning a Catholic Past, Present and Future: Conversion, Recuperation and Andean Christianity in Talavera, Peru
Authors: Lee Christine
Published: September 2021

In the colonial era, many Spanish missionaries in the Andes sought a total temporal and cultural break between the pagan past and desired a Christian future of indigenous Andeans. Discussions of Christian conversion in the modern-day Andes have often echoed this line of thinking, portraying conversion—whether to Protestantism or to Roman Catholicism—as an event of radical discontinuity, and mapping the rupture of conversion onto the rupture of the Spanish invasion and subsequent evangelisation of the Americas. In doing so, however, scholars have often portrayed Catholicism as a veneer over the ‘authentic’ Andes—which was assumed to not be Catholic, and indeed could never be. Recently, however, in the south-central Peruvian Andean parish of Talavera—under the guidance of a first generation of an indigenous Catholic priesthood, made up entirely of men born and raised in the local area—discourses surrounding conversion portray the past as a source of continuity rather than discontinuity with Catholicism. Drawing from historical and ethnographic sources, this article demonstrates that although conversion has been and continues to be an important point of reference in contemporary Roman Catholicism in the Andes, the question of what people convert from has shifted. Today, the Andes are spoken of as already inherently and profoundly Catholic; conversion, in the sense of the need to make the Andes ‘really’ Catholic, is considered long accomplished. As the article discusses, in a national context where Catholicism is dominant and ubiquitous to the point of hegemony, this is an inherently political stance which runs counter to longstanding harmful stereotypes of indigenous Andeans as not ‘real’ Catholics and thus unable to be ‘real’ Peruvians.
Clinical Discernment, Bone Marrow, and Molecular Diagnostics Are Equally Important to Solve the Phenotypic Mimicry among Subtypes of Myeloproliferative Neoplasms
Authors: Schulze Susann , Jaekel Nadia , Naumann Christin Le Hoa , Haak Anja , Bauer Marcus , Wickenhauser Claudia , Al-Ali Haifa Kathrin
Published: September 2021

The 2016 WHO classification integrates clinical, bone marrow (BM)-morphology, and molecular features to define disease entities. This together with the advancements in molecular detection and standardization of BM features enable an accurate diagnosis of myeloproliferative neoplasms (MPN) in the majority of patients. Diagnostic challenges remain due to phenotypic mimicry of MPN, failing specificity of BM-morphology, and the fact that phenotype-driver mutations, such as JAK2V617F, are not exclusive to a particular MPN, and their absence does not preclude any of these. We present a series of cases to illustrate themes to be considered in complex cases of MPN, such as triple-negative (TN)-MPN or MPN-unclassifiable (MPN-U). Eleven patients labelled as TN-MPN or MPN-U were included. Serum tryptase and NGS were part of a systematic/sequential multidisciplinary evaluation. Results were clustered into four categories based on diagnostic entities and/or how these diagnoses were made: (A) With expanding molecular techniques, BCR-ABL1 and karyotyping should not be missed; (B) systemic mastocytosis is underdiagnosed and often missed; (C) benign non-clonal disorders could mimic MPN; and (D) NGS could prove clonality in some “TN”-MPN cases. The prognostic/therapeutic consequences of an accurate diagnosis are immense. In TN-MPN or MPN-U cases, a multidisciplinary re-evaluation integrating molecular results, BM-morphology, and clinical judgment is crucial.