bluuebunny/crossref_metadata_2025 huggingface dataset:
PARP Inhibitors in Biliary Tract Cancer: A New Kid on the Block?
Authors: Ricci Angela Dalia , Rizzo Alessandro , Bonucci Chiara , Tober Nastassja , Palloni Andrea , Mollica Veronica , Maggio Ilaria , Deserti Marzia , Tavolari Simona , Brandi Giovanni
Published: August 2020

Poly adenosine diphosphate-ribose polymerase inhibitors (PARPi) represent an effective therapeutic strategy for cancer patients harboring germline and somatic aberrations in DNA damage repair (DDR) genes. BRCA1/2 mutations occur at 1–7% across biliary tract cancers (BTCs), but a broader spectrum of DDR gene alterations is reported in 28.9–63.5% of newly diagnosed BTC patients. The open question is whether alterations in genes that are well established to have a role in DDR could be considered as emerging predictive biomarkers of response to platinum compounds and PARPi. Currently, data regarding PARPi in BTC patients harboring BRCA and DDR mutations are sparse and anecdotal; nevertheless, a variety of clinical trials are testing PARPi as monotherapy or in combination with other anticancer agents. In this review, we provide a comprehensive overview regarding the genetic landscape of DDR pathway deficiency, state of the art and future therapeutic implications of PARPi in BTC, looking at combination strategies with immune-checkpoint inhibitors and other anticancer agents in order to improve survival and quality of life in BTC patients.
Molecular Interaction, Chain Conformation, and Rheological Modification during Electrospinning of Hyaluronic Acid Aqueous Solution
Authors: Chen Hao , Chen Xuhong , Chen Huiying , Liu Xin , Li Junxing , Luo Jun , He Aihua , Han Charles C. , Liu Ying , Xu Shanshan
Published: August 2020

Most of natural water-soluble polymers are difficult to electrospin due to their specific chain conformation in aqueous solution, which limits their applications. This study investigated the effects of polyethylene oxide (PEO) on the electrospinning of hyaluronic acid (HA) in HA/PEO aqueous solutions. The rheological properties of HA/PEO aqueous solutions showed polymer chain entanglement in HA was the essential factor affecting its electrospinnability. Wide-angle X-ray scattering and differential scanning calorimetry analyses of a PEO crystal showed different crystallization behavior of the PEO chain with different molecular weight, which indicates different interaction with HA. A schematic molecular model has been proposed to explain the effect of PEO on the chain conformation of HA along with the relationship between electrospinnability and chain entanglement. PEO with a relatively high molecular weight with limited crystal formation formed extensive chain entanglements with HA, while PEO with relatively low molecular weight weakened the interactions among HA chains. The findings of this study provide a wide perspective to better understand the electrospinning mechanisms of natural polyelectrolytes and usage in tissue engineering.
New Utilization of Specific Biomass: Lignin in the Iron Ore Sintering Process
Authors: Findorák Róbert , Legemza Jaroslav , Fröhlichová Mária , Fabriciová Gabriela , Džupková Martina
Published: August 2020

The use of lignin can be one of the methods of coke powder substitution in the agglomeration process. This article specifies the material research of lignin and the technological and ecological parameters of the agglomeration process in laboratory conditions using biomass lignin. The methodology of the Raman and infrared spectroscopy, representing a new approach in the analysis and assessment for the purposes of material characteristics for the agglomeration process, was applied to study the structure of carbonaceous matter. The material research of lignin has determined that its calorific value corresponds to ca. 80% of the calorific value of coke powder, while its reactivity is higher than that of the coke. Although the substitution of coke powder using different types of waste biomass (e.g., wood sawdust) in the production of the agglomerate is limited to the maximum of 8–15%, in case of lignin, more than 20% can be substituted, while the standard properties of the produced agglomerate are maintained. The lower emissions of sulfur and nitrogen oxides as well as the reduction of carbon footprint in the agglomeration process as a result of the so-called zero CO2 balance in the formation and processing of the biomass represent its positive aspects. Based on the laboratory research of lignin, up to a 50% substitution of coke powder with this type of biomass can be predicted for the technology of agglomerate production in real operation.
Lipidomics Issues on Human Positive ssRNA Virus Infection: An Update
Authors: Balgoma David , Gil-de-Gómez Luis , Montero Olimpio
Published: August 2020

The pathogenic mechanisms underlying the Biology and Biochemistry of viral infections are known to depend on the lipid metabolism of infected cells. From a lipidomics viewpoint, there are a variety of mechanisms involving virus infection that encompass virus entry, the disturbance of host cell lipid metabolism, and the role played by diverse lipids in regard to the infection effectiveness. All these aspects have currently been tackled separately as independent issues and focused on the function of proteins. Here, we review the role of cholesterol and other lipids in ssRNA+ infection.
Simulation of the Slip Velocity Effect in an AC Electrothermal Micropump
Authors: Echouchene Fraj , Al-shahrani Thamraa , Belmabrouk Hafedh
Published: August 2020

The principal aim of this study was to analyze the effect of slip velocity at the microchannel wall on an alternating current electrothermal (ACET) flow micropump fitted with several pairs of electrodes. Using the finite element method (FEM), the coupled momentum, energy, and Poisson equations with and without slip boundary conditions have been solved to compute the velocity, temperature, and electrical field in the microchannel. The effects of the frequency and the voltage, and the electrical and thermal conductivities, respectively, of the electrolyte solution and the substrate material, have been minutely analyzed in the presence and absence of slip velocity. The slip velocity was simulated along the microchannel walls at different values of slip length. The results revealed that the slip velocity at the wall channel has a significant impact on the flow field. The existence of slip velocity at the wall increases the shear stress and therefore enhances the pumping efficiency. It was observed that higher average pumping velocity was achieved for larger slip length. When a glass substrate was used, the effect of the presence of the slip velocity was more manifest. This study shows also that the effect of slip velocity on the flow field is very important and must be taken into consideration in an ACET micropump.
A Concentration Gradients Tunable Generator with Adjustable Position of the Acoustically Oscillating Bubbles
Authors: Liu Bendong , Ma Zhigao , Yang Jiahui , Gao Guohua , Liu Haibin
Published: August 2020

It is essential to control concentration gradients at specific locations for many biochemical experiments. This paper proposes a tunable concentration gradient generator actuated by acoustically oscillating bubbles trapped in the bubble channels using a controllable position based on the gas permeability of polydimethylsiloxane (PDMS). The gradient generator consists of a glass substrate, a PDMS chip, and a piezoelectric transducer. When the trapped bubbles are activated by acoustic waves, the solution near the gas–liquid interface is mixed. The volume of the bubbles and the position of the gas–liquid interface are regulated through the permeability of the PDMS wall. The tunable concentration gradient can be realized by changing the numbers and positions of the bubbles that enable the mixing of fluids in the main channel, and the amplitude of the applied voltage. This new device is easy to fabricate, responsive, and biocompatible, and therefore has great application prospects. In particular, it is suitable for biological research with high requirements for temporal controllability.
Endophytic Fungi of Olive Tree
Authors: Nicoletti Rosario , Di Vaio Claudio , Cirillo Chiara
Published: August 2020

In addition to the general interest connected with investigations on biodiversity in natural contexts, more recently the scientific community has started considering occurrence of endophytic fungi in crops in the awareness of the fundamental role played by these microorganisms on plant growth and protection. Crops such as olive tree, whose management is more and more frequently based on the paradigm of sustainable agriculture, are particularly interested in the perspective of a possible applicative employment, considering that the multi-year crop cycle implies a likely higher impact of these symbiotic interactions. Aspects concerning occurrence and effects of endophytic fungi associated with olive tree (Olea europaea) are revised in the present paper.
Extension of the Shelf-Life of Fresh Pasta Using Chickpea Flour Fermented with Selected Lactic Acid Bacteria
Authors: Schettino Rosa , Pontonio Erica , Gobbetti Marco , Rizzello Carlo Giuseppe
Published: August 2020

Fresh pasta is subjected to rapid spoilage, mainly due to the metabolic activity of bacteria, yeasts, and especially molds, which negatively affect the sensorial characteristics and the safety of the product. In this work, chickpea flour was fermented with selected lactic acid bacteria, characterized in terms of the antifungal activity, and used to fortify fresh semolina pasta. Pasta was characterized and subjected to a long period of storage after being artificially inoculated with Penicillium roqueforti. Conventional fresh semolina pasta, produced with or without calcium propionate addition, was used as a reference. The water/salt-soluble extract from chickpea sourdough exhibited antifungal activity towards a large spectrum of molds. Its purification led to the identification of ten potentially active peptides. Besides the high content of dietary fibers (4.37%) and proteins (11.20%), nutritional improvements, such as the decrease of the antinutritional factors concentration and the starch hydrolysis index (25% lower than the control) and the increase of the protein digestibility (36% higher than the control), were achieved in fresh pasta fortified with the chickpea sourdough. Inhibition of the indicator mold growth during a 40-day storage period was more effective than in pasta added to calcium propionate.
Helicobacter pylori-Derived Outer Membrane Vesicles (OMVs): Role in Bacterial Pathogenesis?
Authors: Jarzab Miroslaw , Posselt Gernot , Meisner-Kober Nicole , Wessler Silja
Published: August 2020

Persistent infections with the human pathogen Helicobacter pylori (H. pylori) have been closely associated with the induction and progression of a wide range of gastric disorders, including acute and chronic gastritis, ulceration in the stomach and duodenum, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric adenocarcinoma. The pathogenesis of H. pylori is determined by a complicated network of manifold mechanisms of pathogen–host interactions, which involves a coordinated interplay of H. pylori pathogenicity and virulence factors with host cells. While these molecular and cellular mechanisms have been intensively investigated to date, the knowledge about outer membrane vesicles (OMVs) derived from H. pylori and their implication in bacterial pathogenesis is not well developed. In this review, we summarize the current knowledge on H. pylori-derived OMVs.
Effects of Red-Bean Tempeh with Various Strains of Rhizopus on GABA Content and Cortisol Level in Zebrafish
Authors: Chen Yo-Chia , Hsieh Shu-Ling , Hu Chun-Yi
Published: August 2020

Tempeh is traditionally produced by fermenting soybean with the fungus Rhizopus oligosporus found in banana leafs. We wanted to investigate if Taiwan’s flavorful red bean could be used as a healthy substitute for soybeans in tempeh. One bioactive component of tempeh is γ-Aminobutyric acid (GABA). We measured GABA content and shelf-life-related antimicrobial activity in red-bean tempeh made with four strains of Rhizopus, one purchased strain of Rhizopus, and an experimental co-cultured group (Rhizopus and Lactobacillus rhamnosus BCRC16000) as well as cortisol in red-bean-tempeh-treated zebrafish. GABA was highest in the co-culture group (19.028 ± 1.831 g kg−1), followed by screened Strain 1, the purchased strain, and screened Strain 4. All strains had antibacterial activity on S. aureus and B. cereus. The extract significantly reduced cortisol in zebrafish. However, Strain 1, with less GABA than some of the other strains, had the best effect on cortisol level, suggesting that other components in red-bean tempeh may also affect stress-related cortisol. We found the benefits of red-bean tempeh to be similar to those reported for soybean-produced tempeh, suggesting that it could be produced as an alternative product. Considering the Taiwanese appreciation of the red-bean flavor, it might find a welcoming market.
Crystal Chemical and Structural Characterization of Natural and Cation-Exchanged Mexican Erionite
Authors: Quiroz-Estrada Karla , Pacella Alessandro , Ballirano Paolo , Hernández-Espinosa Miguel Ángel , Felipe Carlos , Esparza-Schulz Marcos
Published: August 2020

In this work, the chemical structural characterization of the erionite-type zeolite from Agua Prieta, Sonora, México, was performed on both pristine and Na, Ca, and Mg exchanged samples in order to identify the various modifications due to cation exchange. The samples investigated were those that showed the best behaviour of CO2 and CH4 adsorption at zero coverage levels and the higher values of surface area reported in our previous studies. According to the crystal-chemical formula (Na3.44K1.96Mg0.63Ca0.62)[Al8.21Si27.79O71.85]·29.63H2O, the pristine sample has been classified as erionite-Na. Morphological FE-SEM investigation performed on both pristine (ERIN) and Na-exchanged samples (ERINa3) showed a similar range of fiber diameters (27–37 nm). The chemical analyses of the ion-exchanged samples evidenced the upload of Ca and Mg following ion exchange with Na. Rietveld analysis results allowed the identification of the chemical structural modification caused by the ion exchange process, occurring mainly at the Ca1 site.
Oxygen Reduction Reaction in the Field of Water Environment for Application of Nanomaterials
Authors: Su Rongkui , Xie Chuyue , Alhassan Sikpaam Issaka , Huang Shunhong , Chen Runhua , Xiang Siyuan , Wang Zhenxing , Huang Lei
Published: August 2020

Water pollution has caused the ecosystem to be in a state of imbalance for a long time. It has become a major global ecological and environmental problem today. Solving the potential hidden dangers of pollutants and avoiding unauthorized access to resources has become the necessary condition and important task to ensure the sustainable development of human society. To solve such problems, this review summarizes the research progress of nanomaterials in the field of water aimed at the treatment of water pollution and the development and utilization of new energy. The paper also tries to seek scientific solutions to environmental degradation and to create better living environmental conditions from previously published cutting edge research. The main content in this review article includes four parts: advanced oxidation, catalytic adsorption, hydrogen, and oxygen production. Among a host of other things, this paper also summarizes the various ways by which composite nanomaterials have been combined for enhancing catalytic efficiency, reducing energy consumption, recycling, and ability to expand their scope of application. Hence, this paper provides a clear roadmap on the status, success, problems, and the way forward for future studies.
Self-Assembly Synthesis of the MoS2/PtCo Alloy Counter Electrodes for High-Efficiency and Stable Low-Cost Dye-Sensitized Solar Cells
Authors: Zeng Zhi , Wang Dongbo , Wang Jinzhong , Jiao Shujie , Huang Yuewu , Zhao Sixiang , Zhang Bingke , Ma Mengyu , Gao Shiyong , Feng Xingguo , Zhao Liancheng
Published: August 2020

In this work, MoS2 microspheres/PtCo-alloy nanoparticles (MoS2/PtCo-alloy NPs) were composited via a novel and facile process which MoS2 is functionalized by poly (N-vinyl-2-pyrrolidone) (PVP) and self-assembled with PtCo-alloy NPs. This new composite shows excellent electrocatalytic activity and great potential for dye-sensitized solar cells (DSSCs) as a counter electrode (CE) material. Benefiting from heterostructure and synergistic effects, the MoS2/PtCo-alloy NPs exhibit high electrocatalytic activity, low charge-transfer resistance and stability in the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) test. Meanwhile, a high power-conversion efficiency (PCE) of 8.46% is achieved in DSSCs with MoS2/PtCo-alloy NP CEs, which are comparable to traditional Pt CEs (8.45%). This novel composite provides a new high-performance, stable and cheap choice for CEs in DSSCs.
Intermittent Fasting Enhanced the Cognitive Function in Older Adults with Mild Cognitive Impairment by Inducing Biochemical and Metabolic changes: A 3-Year Progressive Study
Authors: Ooi Theng Choon , Meramat Asheila , Rajab Nor Fadilah , Shahar Suzana , Ismail Intan Safinar , Azam Amalina Ahmad , Sharif Razinah
Published: August 2020

Intermittent fasting (IF) refers to various dietary regimens that cycle between a period of non-fasting and a period of total fasting. This study aimed to determine the effects of IF on cognitive function among elderly individuals who practice IF who have mild cognitive impairment (MCI). A total of 99 elderly subjects with MCI of Malay ethnicity without any terminal illness were recruited from a larger cohort study, LRGS TUA. The subjects were divided into three groups, comprising those who were regularly practicing IF (r-IF), irregularly practicing IF (i-IF), and non-fasters (n-IF). Upon 36 months of follow-up, more MCI subjects in the r-IF group reverted to successful aging with no cognitive impairment and diseases (24.3%) compared to those in i-IF (14.2%) and n-IF groups (3.7%). The r-IF group’s subjects exhibited significant increment in superoxide dismutase (SOD) activity and reduction in body weight, levels of insulin, fasting blood glucose, malondialdehyde (MDA), C-reactive protein (CRP), and DNA damage. Moreover, metabolomics analysis showed that IF may modulate cognitive function via various metabolite pathways, including the synthesis and degradation of ketone bodies, butanoate metabolism, pyruvate metabolism, and glycolysis and gluconeogenesis pathways. Overall, the MCI-afflicted older adults who practiced IF regularly had better cognitive scores and reverted to better cognitive function at 36 months follow-up.
Logistic LASSO Regression for Dietary Intakes and Breast Cancer
Authors: McEligot Archana J. , Poynor Valerie , Sharma Rishabh , Panangadan Anand
Published: August 2020

A multitude of dietary factors from dietary fat to macro and micronutrients intakes have been associated with breast cancer, yet data are still equivocal. Therefore, utilizing data from the large, multi-year, cross-sectional National Health and Nutrition Examination Survey (NHANES), we applied a novel, modern statistical shrinkage technique, logistic least absolute shrinkage and selection operator (LASSO) regression, to examine the association between dietary intakes in women, ≥50 years, with self-reported breast cancer (n = 286) compared with women without self-reported breast cancer (1144) from the 1999–2010 NHANES cycle. Logistic LASSO regression was used to examine the relationship between twenty-nine variables, including dietary variables from food, as well as well-established/known breast cancer risk factors, and to subsequently identify the most relevant variables associated with self-reported breast cancer. We observed that as the penalty factor (λ) increased in the logistic LASSO regression, well-established breast cancer risk factors, including age (β = 0.83) and parity (β = −0.05) remained in the model. For dietary macro and micronutrient intakes, only vitamin B12 (β = 0.07) was positively associated with self-reported breast cancer. Caffeine (β = −0.01) and alcohol (β = 0.03) use also continued to remain in the model. These data suggest that a diet high in vitamin B12, as well as alcohol use may be associated with self-reported breast cancer. Nonetheless, additional prospective studies should apply more recent statistical techniques to dietary data and cancer outcomes to replicate and confirm the present findings.
A Call to Action: Now Is the Time to Screen Elderly and Treat Osteosarcopenia, a Position Paper of the Italian College of Academic Nutritionists MED/49 (ICAN-49)
Authors: Montalcini Tiziana , Pujia Arturo , Donini Lorenzo M. , Frittitta Lucia , Galvano Fabio , Natali Andrea , Pironi Loris , Porrini Marisa , Riso Patrizia , Rivellese Angela Albarosa , Russo Diego , Scapagnini Giovanni , Serafini Mauro , Tagliabue Anna , De Lorenzo Antonino
Published: August 2020

Aging is a risk factor for the development of multiple chronic diseases, including cardiovascular disease, cancer and dementia. Life expectancy has increased in certain countries but this phenomenon is associated with a reduction of years of healthy life. Aging is associated with a number of physical and functional changes, especially sarcopenia. Sarcopenia is a clinical condition associated with a decrease in skeletal muscle and muscle strength, however, sarcopenia is a reversible condition. On the basis of the current scientific literature, sarcopenia could more appropriately capture an individual’s vulnerability to negative health-related outcomes since it represents an early form of the chronic diseases. Recognition of this clinical condition can improve the management of older individuals in many different clinical settings. Despite the limitations of the indirect methods used to study body composition, the Italian College of the Academic Nutritionists ME/49 recommends that health authorities and health professionals around the world should make a greater effort to diagnose sarcopenia earlier and to manage it more effectively. In line with the development of cancer screening, the use of two diagnostic tools for sarcopenia (BIA and DXA) should be implemented.
Allergic Bronchopulmonary Aspergillosis in Children with Cystic Fibrosis: An Update on the Newest Diagnostic Tools and Therapeutic Approaches
Authors: Lattanzi Claudia , Messina Giulia , Fainardi Valentina , Tripodi Maria Candida , Pisi Giovanna , Esposito Susanna
Published: August 2020

Cystic fibrosis (CF), the most common autosomal-recessive genetic disease in the Caucasian population, is characterized by frequent respiratory infections and progressive lung disease. Fungal species are commonly found in patients with CF, and among them, Aspergillus fumigatus is the most frequently isolated. While bacteria, particularly Pseudomonas aeruginosa, have a well-established negative effect on CF lung disease, the impact of fungal infections remains unclear. In patients with CF, inhalation of Aspergillus conidia can cause allergic bronchopulmonary aspergillosis (ABPA), a Th2-mediated lung disease that can contribute to disease progression. Clinical features, diagnostic criteria and treatment of ABPA are still a matter of debate. Given the consequences of a late ABPA diagnosis or the risk of ABPA overdiagnosis, it is imperative that the diagnostic criteria guidelines are reviewed and standardized. Along with traditional criteria, radiological features are emerging as tools for further classification as well as novel immunological tests. Corticosteroids, itraconazole and voriconazole continue to be the bedrock of ABPA therapy, but other molecules, such as posaconazole, vitamin D, recombinant INF-γ and Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulators, have been showing positive results. However, few studies have been conducted recruiting CF patients, and more research is needed to improve the prevention and the classification of clinical manifestations as well as to personalize treatment. Early recognition and early treatment of fungal infections may be fundamental to prevent progression of CF disease. The aim of this narrative review is to give an update on ABPA in children with CF.
Characterization of Resveratrol, Oxyresveratrol, Piceatannol and Roflumilast as Modulators of Phosphodiesterase Activity. Study of Yeast Lifespan
Authors: Matencio Adrián , García-Carmona Francisco , López-Nicolás José Manuel
Published: August 2020

Our desire to live longer has led to an ever-increasing number of novel antiaging products. However, few molecules have any real effect and new ones need to be studied before they can be used commercially. In this contribution, activation of the caloric restriction (CR) pathway was studied using different three (resveratrol, oxyresveratrol and piceatannol)—a family with demonstrated bioactivity on phosphodiesterase activity. The high-affinity phosphodiesterase type 2 (PDE2) of Saccharomyces cerevisiae was expressed in Escherichia coli, purified and characterized. The activity and the inhibitory activity of each stilbene was studied, and the findings were compared in vitro and in silico with those obtained with roflumilast—a human PDE4 inhibitor widely used in chronic obstructive pulmonary diseases. Finally, an in vivo chronological lifespan assay using WT S. cerevisiae and ΔPDE2 S. cerevisiae strains was carried out. It was demonstrated that stilbenes can modulate yPDE2 activity, increasing the lifespan of the yeast by 18% over a control (in combination with other pathways). In addition, roflumilast increased the lifespan in the WT strain. The findings as a whole would increase the range of lifespan products available and suggest novel uses for approved drugs.
SAR Analysis of Small Molecules Interfering with Energy-Metabolism in Mycobacterium tuberculosis
Authors: Appetecchia Federico , Consalvi Sara , Scarpecci Cristina , Biava Mariangela , Poce Giovanna
Published: August 2020

Tuberculosis remains the world’s top infectious killer: it caused a total of 1.5 million deaths and 10 million people fell ill with TB in 2018. Thanks to TB diagnosis and treatment, mortality has been falling in recent years, with an estimated 58 million saved lives between 2000 and 2018. However, the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb strains is a major concern that might reverse this progress. Therefore, the development of new drugs acting upon novel mechanisms of action is a high priority in the global health agenda. With the approval of bedaquiline, which targets mycobacterial energy production, and delamanid, which targets cell wall synthesis and energy production, the energy-metabolism in Mtb has received much attention in the last decade as a potential target to investigate and develop new antimycobacterial drugs. In this review, we describe potent anti-mycobacterial agents targeting the energy-metabolism at different steps with a special focus on structure-activity relationship (SAR) studies of the most advanced compound classes.
Phytochemical and Pharmacological Study of the Eysenhardtia Genus
Authors: Garcia-Campoy Abraham , Garcia Efrén , Muñiz-Ramirez Alethia
Published: August 2020

The participation of natural products in health care has been remarkable, and today they continue to play a key role in the discovery and development of new treatments. Phytochemical studies together with pharmacological tests have managed to integrate bioactive agents as an alternative solution to reduce or regulate the problems caused by diseases. The Eysenhardtia genus is a family of plants that are rich in secondary metabolites, which have shown potential activity in the control and mitigation of urinary disorders, diabetes, oxidative stress, protein glycosylation, microbial infections, inflammation, pain or discomfort, muscle contractions, cytotoxicity, or as a cellular or neuronal signaling modulator. These conditions generally appear in comorbid diseases, which motivated the bibliographic review associated with the plant. This document presents the beneficial actions produced by Eysenhardtia extracts and/or bioactives to inhibit, control, or reduce the complications or discomfort of degenerative diseases and thus generate new therapeutic alternatives.
Simulated Photovoltaic Solar Panels Alter the Seed Bank Survival of Two Desert Annual Plant Species
Authors: Hernandez Rebecca R. , Tanner Karen E. , Haji Sophia , Parker Ingrid M. , Pavlik Bruce M. , Moore-O’Leary Kara A.
Published: August 2020

Seed bank survival underpins plant population persistence but studies on seed bank trait-environment interactions are few. Changes in environmental conditions relevant to seed banks occur in desert ecosystems owing to solar energy development. We developed a conceptual model of seed bank survival to complement methodologies using in-situ seed bank packets. Using this framework, we quantified the seed bank survival of two closely related annual desert plant species, one rare (Eriophyllum mohavense) and one common (Eriophyllum wallacei), and the seed bank–environment interactions of these two species in the Mojave Desert within a system that emulates microhabitat variation associated with solar energy development. We tracked 4860 seeds buried across 540 seed packets and found, averaged across both species, that seed bank survival was 21% and 6% for the first and second growing seasons, respectively. After two growing seasons, the rare annual had a significantly greater seed bank survival (10%) than the common annual (2%). Seed bank survival across both species was significantly greater in shade (10%) microhabitats compared to runoff (5%) and control microhabitats (3%). Our study proffers insight into this early life-stage across rare and common congeners and their environmental interactions using a novel conceptual framework for seed bank survival.
Communities of Fungi in Black Cherry Stumps and Effects of Herbicide
Authors: Korzeniewicz Robert , Baranowska Marlena , Kwaśna Hanna , Niedbała Gniewko , Behnke-Borowczyk Jolanta
Published: August 2020

So far, there have been no studies on fungal communities in Prunus serotina (black cherry) wood. Our objectives were to characterize fungal communities from P. serotina wood and to evaluate effects of glyphosate (Glifocyd 360 SL) used on P. serotina stumps on abundance, species richness and diversity of those communities. In August 2016, in the Podanin Forest District, stumps of black cherry trees left after felling were treated with the herbicide. Control stumps were treated with water. Wood discs were cut from the surface of the stumps in May and July–August 2017. Eight treatment combinations (2 herbicide treatments × 2 disc sizes × 2 sample times) were tested. Sub-samples were pooled and ground in an acryogenic mill. Environmental DNA was extracted with a Plant Genomic DNA Purification Kit. The ITS1, 5.8S rDNA region was used to identify fungal species, using primers ITS1FI2 5′-GAACCWGCGGARGGATCA-3′ and 5.8S 5′-CGCTGCGTT CTTCATCG-3′. The amplicons were sequenced using the Illumina system. The results were subjected to bioinformatic analysis. Sequences were compared with reference sequences from the NCBI database using the BLASTn 2.8.0 algorithm. Abundance of fungi was defined as the number of Operational Taxonomic Units (OTUs), and diversity as the number of species in a sample. Differences between the number of OTUs and taxa were analyzed using the chi-squared test (χ2). Diversity in microbial communities was compared using diversity indices. A total of 54,644 OTUs were obtained. Culturable fungi produced 49,808 OTUs (91.15%), fungi not known from culture had 2571 OTUs (4.70%), non-fungal organisms had 1333 (2.44%) and organisms with no reference sequence in NCBI, 934 OTUs (1.71%). The total number of taxa ranged from 120 to 319. Fungi in stump wood were significantly more abundant in July–August than in May, in stumps >5 cm diameter than in stumps <5 cm diameter, in glyphosate-treated than in untreated stumps when sampled in May, and in untreated than in glyphosate-treated stumps when sampled in July–August. Species richness was significantly greater in July–August than in May, and in stumps >5 cm diameter than in stumps <5 cm diameter, either treated or untreated, depending on size. Herbicides can therefore affect the abundance and diversity of fungal communities in deciduous tree wood. The greater frequency of Ascomycota in herbicide-treated than in untreated stumps indicates their greater tolerance of glyphosate.
Toward Unifying Global Hotspots of Wild and Domesticated Biodiversity
Authors: Pironon Samuel , Borrell James S. , Ondo Ian , Douglas Ruben , Phillips Charlotte , Khoury Colin K. , Kantar Michael B. , Fumia Nathan , Soto Gomez Marybel , Viruel Juan , Govaerts Rafael , Forest Félix , Antonelli Alexandre
Published: August 2020

Global biodiversity hotspots are areas containing high levels of species richness, endemism and threat. Similarly, regions of agriculturally relevant diversity have been identified where many domesticated plants and animals originated, and co-occurred with their wild ancestors and relatives. The agro-biodiversity in these regions has, likewise, often been considered threatened. Biodiversity and agro-biodiversity hotspots partly overlap, but their geographic intricacies have rarely been investigated together. Here we review the history of these two concepts and explore their geographic relationship by analysing global distribution and human use data for all plants, and for major crops and associated wild relatives. We highlight a geographic continuum between agro-biodiversity hotspots that contain high richness in species that are intensively used and well known by humanity (i.e., major crops and most viewed species on Wikipedia) and biodiversity hotspots encompassing species that are less heavily used and documented (i.e., crop wild relatives and species lacking information on Wikipedia). Our contribution highlights the key considerations needed for further developing a unifying concept of agro-biodiversity hotspots that encompasses multiple facets of diversity (including genetic and phylogenetic) and the linkage with overall biodiversity. This integration will ultimately enhance our understanding of the geography of human-plant interactions and help guide the preservation of nature and its contributions to people.
The Role of Genetic Resources in Breeding for Climate Change: The Case of Public Breeding Programmes in Eighteen Developing Countries
Authors: Galluzzi Gea , Seyoum Aseffa , Halewood Michael , López Noriega Isabel , Welch Eric W.
Published: August 2020

The role of plant breeding in adapting crops to climate changes that affect food production in developing countries is recognized as extremely important and urgent, alongside other agronomic, socio-economic and policy adaptation pathways. To enhance plant breeders’ capacity to respond to climate challenges, it is acknowledged that they need to be able to access and use as much genetic diversity as they can get. Through an analysis of data from a global survey, we explore if and how public breeders in selected developing countries are responding to climate challenges through a renewed or innovative use of plant genetic resources, particularly in terms of types of material incorporated into their breeding work as well as sources of such germplasm. It also looks at the possible limitations breeders encounter in their efforts towards exploring diversity for adaptation. Breeders are clearly considering climate challenges. In general, their efforts are aimed at intensifying their breeding work on traits that they were already working on before climate change was so widely discussed. Similarly, the kinds of germplasm they use, and the sources from which they obtain it, do not appear to have changed significantly over the course of recent years. The main challenges breeders faced in accessing germplasm were linked to administrative/legal factors, particularly related to obtaining genetic resources across national borders. They also underscore technical challenges such as a lack of appropriate technologies to exploit germplasm sets such as crop wild relatives and landraces. Addressing these limitations will be crucial to fully enhance the role of public sector breeders in helping to adapt vulnerable agricultural systems to the challenges of climate change.
Enhanced Photodegradation Stability in Poly(butylene adipate-co-terephthalate) Composites Using Organically Modified Layered Zinc Phenylphosphonate
Authors: Wang Jie-Mao , Wang Hao , Chen Erh-Chiang , Chen Yun-Ju , Wu Tzong-Ming
Published: August 2020

The enhancement of the ultraviolet (UV) photodegradation resistance of biodegradable polymers can improve their application efficacy in a natural environment. In this study, the hexadecylamine modified layered zinc phenylphosphonate (m-PPZn) was used as a UV protection additive for poly(butylene adipate-co-terephthalate) (PBAT) via solution mixing. The results from the Fourier transform infrared spectroscopy (FTIR) and wide-angle X-ray diffraction analysis of the m-PPZn indicated the occurrence of hexadecylamine intercalation. FTIR and gel permeation chromatography were used to characterize the evolution of the PBAT/m-PPZn composites after being artificially irradiated via a light source. The various functional groups produced via photodegradation were analyzed to illustrate the enhanced UV protection ability of m-PPZn in the composite materials. From the appearance, the yellowness index of the PBAT/m-PPZn composite materials was significantly lower than that of the pure PBAT matrix due to photodegradation. These results were confirmed by the molecular weight reduction in PBAT with increasing m-PPZn content, possibly due to the UV photon energy reflection by the m-PPZn. This study presents a novel approach of improving the UV photodegradation of a biodegradable polymer using an organically modified layered zinc phenylphosphonate composite.
pH-Sensitive Starch-Based Hydrogels: Synthesis and Effect of Molecular Components on Drug Release Behavior
Authors: Quintanilla de Stéfano Juan Carlos , Abundis-Correa Vanessa , Herrera-Flores Sergio Daniel , Alvarez Alejandro J.
Published: August 2020

The drug release behavior of pH-sensitive starch-based hydrogels was systematically studied. Hydrogels were synthesized by copolymerization of acrylic acid (AA) and other acrylate comonomers onto the starch backbone. The hydrophilic agents 2-hydroxy ethyl methacrylate (HEMA), and acrylamide (AAm), as well as the hydrophobic butyl-methacrylate (BMA), were utilized as comonomers. Methylene-bisacrylamide (MBA) was employed as a crosslinking agent. The synthesized hydrogels were loaded with caffeine as a model drug. The effects of the hydrophobic/hydrophilic character of the comonomers and chemical crosslinking on the swelling capacity and the release rate of caffeine were investigated. The use of the crosslinking agent and hydrophobic monomers decreased the swelling capacity of the hydrogels. The release rate of caffeine increased with the presence of a hydrophobic monomer. The fastest release was obtained with the AA/BMA/AAm formulation, and the slowest release was observed with the AA/HEMA/AAm formulation. The transport mechanism was controlled by Fickian diffusion in formulations containing AAm, and controlled by the polymer-relaxation mechanism in formulations containing MBA. Overall, our results showed that the swelling and drug delivery behavior can be tuned by varying the chemical composition of the copolymer formulations. These starch-based hydrogels can be useful as drug delivery devices in many biomedical applications.
Macromolecular Dyes by Chromophore-Initiated Ring Opening Polymerization of L-Lactide
Authors: Cicogna Francesca , Giachi Guido , Rosi Luca , Passaglia Elisa , Coiai Serena , Spiniello Roberto , Prescimone Federico , Frediani Marco
Published: August 2020

End functionalized polylactides are prepared by ring opening polymerization of L-lactide in the presence of stannous octoate (Sn(Oct)2). Three chromophores, 9H-carbazol-ethanol (CA), 9-fluorenyl-methanol (FM), and 2-(4-(2-chloro-4-nitrophenylazo)-N-ethylphenylamino)ethanol (Disperse Red 13, DR), are for the first time used as co-initiators in the polymerization process. The polymerization reaction is initiated by conventional thermal treatment, but in the case of FM, microwave-assisted polymerization is also carried out. CA and FM absorb and emit in the UV portion of the electromagnetic spectrum, whereas DR absorbs in the visible part. The obtained end-capped polylactides derivatives show the same photophysical properties as the initiator, so they are “macromolecular dyes” (MDs) that can be used “as synthesized” or can be blended with commercial poly(lactic acid) (PLA). The blends of PLA with MDs have ultraviolet-visible (UV-Vis) absorption and fluorescence emission features similar to that of MDs and thermal properties typical of PLA. Finally, migration tests, carried out onto the blends of PLA with MDs and PLA with free chromophores, show that MDs are less released than free chromophores both in solution and in the solid phase.
3D Printing of a Reactive Hydrogel Bio-Ink Using a Static Mixing Tool
Authors: Puertas-Bartolomé María , Włodarczyk-Biegun Małgorzata K. , del Campo Aránzazu , Vázquez-Lasa Blanca , San Román Julio
Published: August 2020

Hydrogel-based bio-inks have recently attracted more attention for 3D printing applications in tissue engineering due to their remarkable intrinsic properties, such as a cell supporting environment. However, their usually weak mechanical properties lead to poor printability and low stability of the obtained structures. To obtain good shape fidelity, current approaches based on extrusion printing use high viscosity solutions, which can compromise cell viability. This paper presents a novel bio-printing methodology based on a dual-syringe system with a static mixing tool that allows in situ crosslinking of a two-component hydrogel-based ink in the presence of living cells. The reactive hydrogel system consists of carboxymethyl chitosan (CMCh) and partially oxidized hyaluronic acid (HAox) that undergo fast self-covalent crosslinking via Schiff base formation. This new approach allows us to use low viscosity solutions since in situ gelation provides the appropriate structural integrity to maintain the printed shape. The proposed bio-ink formulation was optimized to match crosslinking kinetics with the printing process and multi-layered 3D bio-printed scaffolds were successfully obtained. Printed scaffolds showed moderate swelling, good biocompatibility with embedded cells, and were mechanically stable after 14 days of the cell culture. We envision that this straightforward, powerful, and generalizable printing approach can be used for a wide range of materials, growth factors, or cell types, to be employed for soft tissue regeneration.
Research on the Dynamic Characteristics of Mechanical Seal under Different Extrusion Fault Degrees
Authors: Luo Yin , Fan Yakun , Han Yuejiang , Zhang Weqi , Acheaw Emmanuel
Published: August 2020

In order to explore the dynamic characteristics of the mechanical seal under different fault degrees, this paper selected the upstream pumping mechanical seal as the object of study. The research established the rotating ring-fluid film-stationary ring 3D model, which was built to analyze the fault mechanism. To study extrusion fault mechanism and characteristics, different dynamic parameters were used in the analysis process. Theoretical analysis, numerical simulation, and comparison were conducted to study the relationship between the fault degree and dynamic characteristics. It is the first time to research the dynamic characteristics of mechanical seals in the specific extrusion fault. This paper proved feasibility and effectiveness of the new analysis method. The fluid film thickness and dynamic characteristics could reflect the degree of the extrusion fault. Results show that the fluid film pressure fluctuation tends to be more intensive under the serious extrusion fault condition. The extrusion fault is more likely to occur when the fluid film thickness is too large or too small. Results illustrate the opening force is affected with the fluid film lubrication status and seal extrusion fault degrees. The fluid film stiffness would not always increase with the rotating speed growth. The seal fault would occur with the increasing of rotating speeds, and the leakage growth fluctuations could reflect the fault degree.
Molecular Identification and VOMs Characterization of Saccharomyces cerevisiae Strains Isolated from Madeira Region Winery Environments
Authors: Castillo Mariangie , Silva Emanuel da , Câmara José S. , Khadem Mahnaz
Published: August 2020

The quality and typical characteristic of wines depends, among other factors, on the volatile organic metabolites (VOMs) that are biosynthesized by yeasts, mainly Saccharomyces cerevisiae species. The yeast strain influences the diversity and proportions of the VOMs produced during the fermentation process, as the genetic predisposition of the strains is a by-product of selective adaptation to the ecosystem. The present work reports the characterization of S. cerevisiae strains isolated from grape must, used in the Demarcated Region of Madeira (DRM) for winemaking. Yeast species were identified by amplification and by restriction fragment length polymorphism (RFLP) analysis of the region 5.8S-internal transcribed spacers (PCR-RFLP of 5.8S-ITS) of ribosomal DNA (rDNA). The strains identification was performed by analyzing the RFLP pattern of mitochondrial DNA (RFLP-mtDNA). The representative strains were selected for the characterization of the volatile profile through headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. A total of 77 VOMs were identified. Higher alcohols, esters, and fatty acids were the major chemical families representing 63%, 16%, and 9%, respectively, in strain A and 54%, 23%, and 15% in strain B. The results indicate the influence of the strain metabolism in the production of VOMs, many of which probably participate in the aroma of the corresponding wines.
Predictors of Self-Reported Growth Following Religious and Spiritual Struggles: Exploring the Role of Wholeness
Authors: Hart Allison C. , Pargament Kenneth I. , Grubbs Joshua B. , Exline Julie J. , Wilt Joshua A.
Published: August 2020

Religious and spiritual (r/s) struggles have been robustly linked to negative outcomes, such as greater psychological distress, reduced well-being, and difficulty finding meaning in life. R/s struggles, however, do not inevitably lead to decline. Many people report post-traumatic and spiritual growth through their r/s struggles, even though correlational studies linking r/s struggles to perceptions of growth have produced mixed results. How do we make sense of this overall pattern of findings? Perhaps growth following r/s struggles occurs under certain conditions. Prior conceptual work by Pargament suggests that specific aspects of one’s orienting system (i.e., the confluence of r/s, dispositional, and psychosocial factors which help guide people in their search for significance and purpose) may play a pivotal role in predicting growth or decline in the wake of an r/s struggle. In the present empirical study, we expected to find that among r/s strugglers, those with orienting systems marked by greater wholeness would be more likely to report growth and less decline. Four dimensions of greater wholeness (purposiveness, breadth and depth, life affirmation, cohesiveness) were measured by the presence of meaning in one’s life, self-control, universality, optimism, compassion, openness to change while tolerating doubt, and a collaborative problem-solving relationship with God. We tested these hypotheses using data from a cross-sectional study (N = 1162) of undergraduates at three universities. Results generally supported our hypotheses, with a few exceptions. Greater wholeness was associated with reports of more growth and less decline after an r/s struggle.