bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulmonary sclerosing pneumocytoma: Cytomorphology and immunoprofile
Authors: Maleki Zahra , Muller Stephanie , Layfield Lester , Siddiqui Momin T. , Rekhtman Natasha , Pantanowitz Liron
Published: February 2020

Background

Sclerosing pneumocytoma (SP) is a rare, benign pulmonary neoplasm. To the authors' knowledge, the current study is the first to evaluate the cytomorphology and immunoprofile of SP in a series.

Methods

A total of 9 fine‐needle aspiration cases of SP (7 of which were computed tomography guided and 2 of which were endobronchial ultrasound guided) including histopathology and immunohistochemistry were collected from 5 institutions.

Results

The female‐to‐male ratio was 3.5:1, and the mean age of the patients was 54 years (range, 27‐73 years). All cases presented as lung nodules, with a mean size of 2.2 cm (range, 1.1‐5 cm), and were interpreted as atypical on rapid on‐site evaluation. The final diagnoses were favor adenocarcinoma (1 case), well‐differentiated lung adenocarcinoma (2 cases), low‐grade epithelial neoplasm (2 cases), and sclerosing pneumocytoma (4 cases). Samples were moderately cellular, and consisted of round epithelioid cells with clear cell features, columnar cells, and spindle cells. A papillary arrangement with prominent hyalinized fibrovascular cores was the most common architectural pattern, followed by flat sheets and acinar formations. Tumor cells demonstrated mild, focally moderate nuclear pleomorphism with prominent nucleoli, hyperchromasia, nuclear elongation, nuclear overlap, and occasional nuclear inclusions and grooves. The background consisted of foamy macrophages (9 cases), hemosiderin pigment (6 cases), and lymphoid aggregates (3 cases) with no mitoses and/or necrosis. The surface cells and underlying round cells were positive for both thyroid transcription factor 1 and epithelial membrane antigen in all cases, which was the most notable immunohistochemical finding.

Conclusions

Cytomorphological findings of SP overlap with those of well‐differentiated lung adenocarcinoma. Awareness of these cytomorphologic findings and the distinct immunoprofile of the 2 cell types found in SP should prevent a misdiagnosis and aggressive treatment.
Whistle variation in Mediterranean common bottlenose dolphin: The role of geographical, anthropogenic, social, and behavioral factors
Authors: La Manna Gabriella , Rako‐Gospić Nikolina , Sarà Gianluca , Gatti Federica , Bonizzoni Silvia , Ceccherelli Giulia
Published: February 2020

The studies on the variation of acoustic communication in different species have provided insight that genetics, geographic isolation, and adaptation to ecological and social conditions play important roles in the variability of acoustic signals. The dolphin whistles are communication signals that can vary significantly among and within populations. Although it is known that they are influenced by different environmental and social variables, the factors influencing the variation between populations have received scant attention. In the present study, we investigated the factors associated with the acoustic variability in the whistles of common bottlenose dolphin (Tursiops truncatus), inhabiting two Mediterranean areas (Sardinia and Croatia). We explored which factors, among (a) geographical isolation of populations, (b) different environments in terms of noise and boat presence, and (c) social factors (including group size, behavior, and presence of calves), were associated with whistle characteristics. We first applied a principal component analysis to reduce the number of collinear whistle frequency and temporal characteristics and then generalized linear mixed models on the first two principal components. The study revealed that both geographic distance/isolation and local environment are associated with whistle variations between localities. The prominent differences in the acoustic environments between the two areas, which contributed to the acoustic variability in the first principal component (PC1), were found. The calf's presence and foraging and social behavior were also found to be associated with dolphin whistle variation. The second principal component (PC2) was associated only with locality and group size, showing that longer and more complex tonal sound may facilitate individual recognition and cohesion in social groups. Thus, both social and behavioral context influenced significantly the structure of whistles, and they should be considered when investigating acoustic variability among distant dolphin populations to avoid confounding factors.
Cascading effects of climate change on plankton community structure
Authors: Murphy Grace E. P. , Romanuk Tamara N. , Worm Boris
Published: February 2020

Plankton communities account for at least half of global primary production and play a key role in the global carbon cycle. Warming and acidification may alter the interaction chains in these communities from the bottom and top of the food web. Yet, the relative importance of these potentially complex interactions has not yet been quantified. Here, we examine the isolated and combined effects of warming, acidification, and reductions in phytoplankton and predator abundances in a series of factorial experiments. We find that warming directly impacts the top of the food web, but that the intermediate trophic groups are more strongly influenced by indirect effects mediated by altered top‐down interactions. Direct manipulations of predator and phytoplankton abundance reveal similar strong top‐down interactions following top predator decline. A meta‐analysis of published experiments further supports the conclusion that warming has stronger direct impacts on the top and bottom of the food web rather than the intermediate trophic groups, with important differences between freshwater and marine plankton communities. Our results reveal that the trophic effect of warming cascading down from the top of the plankton food web is a powerful agent of global change.
Molecular and ecological plant defense responses along an elevational gradient in a boreal ecosystem
Authors: Benevenuto Rafael Fonseca , Seldal Tarald , Polashock James , Moe Stein R. , Rodriguez‐Saona Cesar , Gillespie Mark A. K. , Hegland Stein Joar
Published: February 2020

Plants have the capacity to alter their phenotype in response to environmental factors, such as herbivory, a phenomenon called phenotypic plasticity. However, little is known on how plant responses to herbivory are modulated by environmental variation along ecological gradients. To investigate this question, we used bilberry (Vaccinium myrtillus L.) plants and an experimental treatment to induce plant defenses (i.e., application of methyl jasmonate; MeJA), to observe ecological responses and gene expression changes along an elevational gradient in a boreal system in western Norway. The gradient included optimal growing conditions for bilberry in this region (ca. 500 m a.s.l.), and the plant's range limits at high (ca. 900 m a.s.l.) and low (100 m a.s.l.) elevations. Across all altitudinal sites, MeJA‐treated plants allocated more resources to herbivory resistance while reducing growth and reproduction than control plants, but this response was more pronounced at the lowest elevation. High‐elevation plants growing under less herbivory pressure but more resource‐limiting conditions exhibited consistently high expression levels of defense genes in both MeJA‐treated and untreated plants at all times, suggesting a constant state of “alert.” These results suggest that plant defense responses at both the molecular and ecological levels are modulated by the combination of climate and herbivory pressure, such that plants under different environmental conditions differentially direct the resources available to specific antiherbivore strategies. Our findings are important for understanding the complex impact of future climate changes on plant–herbivore interactions, as this is a major driver of ecosystem functioning and biodiversity.
Experimental study of coalbed methane thermal recovery
Authors: Cao Yuanhao , Chen Wei , Yuan Yinnan , Wang Tengxi , Sun Jiafeng , Cai Yidong
Published: February 2020

Extracting coalbed methane is challenging due to the strong gas adsorption capacity and low matrix permeability of the coalbed. Recently, thermal recovery methods have been tested to promote methane recovery. In this study, anthracite samples were heated to different temperatures to investigate the internal pressure variation and microstructure changes. It was found that higher temperature resulted in higher internal pressure. At low temperatures, the increase in the internal pressure was mainly due to gas desorption. At 500°C, thermal cracking gases provided the main contribution to the high internal pressures, as more gaseous products were generated at the higher temperature. In addition, the microstructure of coal significantly changed after combustion, including the increased pore volume, the increased specific surface area, and the generation of microfractures. These changes could potentially increase the porosity and permeability of coal. Thus, high‐temperature thermal treatments not only provided energy for gas desorption and organic matter decomposition but also improved conditions for gas transport.
Effect on amino acid and mineral content of the loach (Misgurnus anguillicaudatus) by adding Fe (II) chelating hairtail protein hydrolysates (Fe (II)‐HPH) to the feed
Authors: Miao Jiayu , Lin Huimin , Zhang Shan , Huo Jiancong , Deng Shanggui
Published: February 2020

To study the effect on amino acid and mineral content of the loach meat by adding Fe (II) chelating hairtail protein hydrolysates (Fe (II)‐HPH) to the feed. A total of 100 healthy loaches were selected. After 1 week's adaptive feeding, they were randomly divided into five groups and fed with feeds containing of Fe (II)‐HPH (0, 0.5, 1, 2, and 4 g/kg). On the 40th day, detection work of general nutrients (moisture, ash, crude protein, and crude fat), mineral elements (Fe, Mn, Cu, Zn, Na, K, and Ca), amino acid and amino acid score (AAS), Chemical Score (CS) and essential amino acid index (EAAI) indexes were done. The results show that crude protein has the highest content while crude fat has the lowest when amount of added Fe (II)‐HPH in feed is 2 g/kg. The Fe content is significantly improved while amount of added is 1, 2, 4 g/kg. The Ca content is significantly improved and the Zn content is significantly improved while amount of added was 2 g/kg. Mn contents are significantly lower than control while amount of added is 4 g/kg. Based on analysis of amino acids in each group, the nutritional value of loach meat with 2 g/kg Fe (II)‐HPH addition amount is relatively high, total amount of essential amino acids increases significantly, and EAA/TAA and EAA/NEAA improve significantly. In conclusion, adding 2 g/kg Fe (II)‐HPH to feed could improve the nutritional values of loach meat.
Survival analysis for long noncoding RNAs identifies TP53TG1 as an antioncogenic target for the breast cancer
Authors: Shao Mei , Ma Huali , Wan Xing , Liu Yuhai
Published: February 2020

Breast carcinoma is one of the most commonly diagnosed tumors and also one of the deadliest cancers in the female. Long noncoding RNAs (lncRNAs) are emerging as novel targets and biomarkers for breast cancer diagnosis and treatment. In this study, we aimed to study the lncRNAs associated with the outcomes in patients using the breast invasive carcinoma datasets from The Cancer Genome Atlas. The Cox proportional hazards regression model was fitted to each lncRNA. Hierarchy clustering was carried out using these survival‐related lncRNAs and the log‐rank test was carried out for the clustered groups. DNA methylation status was utilized to identify the lncRNAs regulated by epigenetics. Finally, the coexpressed messenger RNA with the potential lncRNAs were utilized to study the possible functions and mechanisms of lncRNAs. In total, 182 lncRNAs had an impact on the survival time of the patients with a cutoff <0.01. The patients were clustered into three groups using these survival‐related genes, which performed significantly different prognosis. Two lncRNAs, which were significantly correlated with the outcomes of breast cancer and were regulated by methylation status, were obtained. These two lncRNAs were TP53TG1 and RP5‐1061H20.4. We proposed that TP53TG1 was activated by the wild‐type TP53 and performed an impact on the PI3Ks family by binding YBX2 in breast cancer.
Potential factors modulating ENSO's influences on the East Asian trough in boreal winter
Authors: Yu Shui , Sun Jianqi
Published: February 2020

The eastern Pacific (EP) El Niño‐Southern Oscillation (ENSO) is an important impact factor for the East Asian trough (EAT) variability during boreal winter. However, not all ENSO events can result in anomalous EAT events, which indicates that there could be some other factors modulating the relationship between ENSO and the EAT. The analysis of atmospheric circulations indicates that the intensity of the Asian Polar vortex (PV) plays an important role in the El Niño‐EAT connection. The strengthened Asian PV favours the wave‐train triggered by El Niño events propagates eastward from the North Pacific to East Asia and finally weakens the EAT. In contrast, during El Niño years with the weakened Asian PV, El Niño's influences are confined over western Siberia and the wave activity flux over Eurasia is weak, which consequently leads to a weak response of the EAT. For the La Niña‐EAT connection, the North Pacific Oscillation (NPO) is a potential modulating factor. The La Niña and negative‐phase NPO have a strengthened effect on the EAT, resulting in a strong response of the EAT to La Niña events. In contrast, the effects of La Niña and positive‐phase NPO on the EAT are offset, leading to a weak response of the EAT to La Niña events. The above results are further confirmed by a numerical simulation of the pre‐industrial Control experiment. Therefore, the simultaneous occurrence of the Asian PV and NPO should be a great concern when understanding and predicting the EAT based on ENSO information.
Novel Elastically Stretchable Metal–Organic Framework Laden Hydrogel with Pearl–Net Microstructure and Freezing Resistance through Post‐Synthetic Polymerization
Authors: Xu Jun , Wu Congyi , Qiu Yue , Tang Xing , Zeng Dawen
Published: February 2020

Nanocomposite hydrogels (NCs) with mechanical properties suitable for a diverse range of applications can be made by combining polymer hydrogel networks with various inorganic nanoparticles. However, the mechanical properties and functions of conventional NCs are seriously limited by the poor structural or functional tunability of common nanofillers and by the low amounts of such fillers that can be added. Here, the fabrication of novel elastically stretchable and compressible nanocomposite hydrogels (MIL‐101‐MAAm/PAAm) with a distinctive pearl–net microstructure and a metal–organic framework (MOF) content in the range of 20–60 wt% through post‐synthetic polymerization (PSP) is reported. The MOFs, which are compatible with polymers and have a high degree of modifiability in structure and functions, are used as nanofillers. Such MOF‐laden hydrogels can withstand 500% tensile strain or 90% compressive strain without fracture and recover quickly upon unloading. They are also resistant to freezing at −25 °C. In addition, the problems associated with poor flexibility and processability of MOFs are overcome by the hybridization of hydrogel polymer matrices with MOFs. The results of this work not only provide a new perspective on preparing NCs but also indicate a promising path for applying MOFs in flexible devices.
Morphological Transformation between Orthogonal Dynamic Covalent Self‐Assembly of Imine‐Boroxine Hybrid Polymer Nanocapsules and Thin Films via Linker Exchange
Authors: Tian Ruizhen , Fan XiaoTong , Liu Shengda , Li Fei , Yang Feihu , Li Yijia , Luo Quan , Hou Chunxi , Xu Jiayun , Liu Junqiu
Published: February 2020

Orthogonal dynamic covalent self‐assembly is used as a facile method for constructing polymer hollow nanocapsules (NCs) and thin films. The bifunctional precursor 4‐formylphenylboronic acid is symmetrically installed with a boronic acid group for the boroxine linkage, and an aldehyde group for the Schiff base reaction which can react with twofold symmetry linkers ethylenediamine and para phenylenediamine to attain polymer NCs and nanosheets. Owing to the reversibility of the imine linkages, the mutual morphological transformation between polymer NCs and thin films via an amine‐imine‐exchange strategy is successfully achieved. Multiple reversible covalent bonds allow the control the release of the load in polymer NCs using different techniques. This may be useful for designing stimulus‐responsive smart materials.
Polymeric Iodonium Salts to Trigger Free Radical Photopolymerization
Authors: Baralle Alexandre , Garra Patxi , Morlet‐Savary Fabrice , Dietlin Céline , Fouassier Jean‐Pierre , Lalevée Jacques
Published: February 2020

In a significant breakthrough from classical molecular (i.e., nonpolymeric) iodonium salts in light‐induced photochemistry, the synthesis and use of new safer polymeric iodonium salts are reported here. They are shown to be involved in charge transfer complexes (CTCs) while in interaction with a safe amino acid derivative (N‐phenylglycine). Also, this study demonstrates i) the formation of CTCs between the iodonium (acceptor) and an aryl/alkyl amine (donor) through UV–vis measurements of the monomer, ii) the formation of radicals in electron spin resonance spin trapping experiments when the CTCs are irradiated by visible light (405 nm), and iii) their efficiency as a photoinitiator to polymerize three different acrylic monomers under LED irradiation at 405 nm under air and their application to 3D resolved laser writing of thick samples (3 mm). High reactivity for polymeric iodonium salts comparable with molecular ones is exhibited with the advantage of potential lower migration. To the best of the authors' knowledge, this is the first reported instance of polymeric iodonium salts acting as polymerization initiators.
Bacterioplankton community variation in Bohai Bay (China) is explained by joint effects of environmental and spatial factors
Authors: Zhao Wei , Wang Jingjing , Xu Song , Lei Yu , Yang Rong , Shi Liuyang , Wang Xingbiao , Huang Zhiyong
Published: February 2020

Parsing the relative importance of environmental (recent disturbances) and spatial factors (historical processes) in determining community structure is a core issue in ecology. The Bohai Bay is a typical semi‐enclosed bay located in the north of China, surrounding by the metropolitan area with anthropogenic disturbances made it a complex marine coastal system with pollution gradients, where the distributions and determinants of bacterioplankton communities remain unclear. In this study, we collected surface water samples from 19 sites across Bohai Bay at about 100 km scale to investigate the relative roles of local environments and regional spatial factors in shaping bacterioplankton community composition (BCC). The environmental parameters in the sampling region showed gradient change according to the geographic variation. Several abundant OTUs were significantly correlated with the pollution parameters in the studied area, and 16 OTUs of them showed distinct distribution pattern in different polluted regions with obvious geographic segmentation, which indicated the effects of pollution gradient and dispersal limitation on specific taxon. The BCCs did not show obviously clustering effect between different polluted regions, which indicated the complexity for explaining the BCC variation in the studied region. The partial Mantel test revealed stronger spatial effects on beta diversity than those of local environmental factors, which indicated that dispersal limitation accounted more for the beta diversity than environmental heterogeneity. Furthermore, variation partitioning analysis (VPA) conducted by combining the environmental variables, linear trends, and principal coordinates of the variables from neighbor matrices (PCNM) showed that it was the joint effects of environmental and spatial factors contributed to the explained variation of BCC in the studied area. Considering the special human geography characteristics of Bohai Bay, the unmeasured biotic/abiotic factors, stochastic factors, and anthropogenic disturbances may be responsible for the unexplained variation of the BCC.
Diffusion‐time dependence of diffusional kurtosis in the mouse brain
Authors: Aggarwal Manisha , Smith Matthew D. , Calabresi Peter A.
Published: February 2020

Purpose

To investigate diffusion‐time dependency of diffusional kurtosis in the mouse brain using pulsed‐gradient spin‐echo (PGSE) and oscillating‐gradient spin‐echo (OGSE) sequences.

Methods

3D PGSE and OGSE kurtosis tensor data were acquired from ex vivo brains of adult, cuprizone‐treated, and age‐matched control mice with diffusion‐time (tD) ~ 20 ms and frequency (f) = 70 Hz, respectively. Further, 2D acquisitions were performed at multiple times/frequencies ranging from f = 140 Hz to tD = 30 ms with b‐values up to 4000 s/mm2. Monte Carlo simulations were used to investigate the coupled effects of varying restriction size and permeability on time/frequency‐dependence of kurtosis with both diffusion‐encoding schemes. Simulations and experiments were further performed to investigate the effect of varying number of cycles in OGSE waveforms.

Results

Kurtosis and diffusivity maps exhibited significant region‐specific changes with diffusion time/frequency across both gray and white matter areas. PGSE‐ and OGSE‐based kurtosis maps showed reversed contrast between gray matter regions in the cerebellar and cerebral cortex. Localized time/frequency‐dependent changes in kurtosis tensor metrics were found in the splenium of the corpus callosum in cuprizone‐treated mouse brains, corresponding to regional demyelination seen with histological assessment. Monte Carlo simulations showed that kurtosis estimates with pulsed‐ and oscillating‐gradient waveforms differ in their sensitivity to exchange. Both simulations and experiments showed dependence of kurtosis on number of cycles in OGSE waveforms for non‐zero permeability.

Conclusion

The results show significant time/frequency‐dependency of diffusional kurtosis in the mouse brain, which can provide sensitivity to probe intrinsic cellular heterogeneity and pathological alterations in gray and white matter.
Chimeric antigen receptor T‐cell therapy in patients with neurologic comorbidities
Authors: Rubinstein Jeremy D. , Nelson Adam S. , Krupski Christa , O'Brien William , Taylor J. Michael , Badgett Tom C. , Huang Michael , Davies Stella M. , Phillips Christine L.
Published: February 2020

Chimeric antigen receptor T cells (CAR‐T) are an effective and potentially durable treatment for refractory and multiply relapsed B‐cell acute lymphoblastic leukemia. Neurotoxicity is frequent after CAR‐T cell therapy. Mechanisms driving neurotoxicity are incompletely understood, and symptoms can range from transient and mild to severe and life‐threatening. Providers have exercised caution in providing CAR‐T to patients with neurological comorbidities or extramedullary disease. Here, we report three patients with prior significant neurologic morbidity who safely tolerated CAR‐T cell infusion after bridging therapy with conventional chemotherapy.
Disassembly of the ring‐type decameric structure of peroxiredoxin from Aeropyrum pernix K1 by amino acid mutation
Authors: Himiyama Tomoki , Nakamura Tsutomu
Published: February 2020

The quaternary structure of peroxiredoxin from Aeropyrum pernix K1 (ApPrx) is a decamer, in which five homodimers are assembled in a pentagonal ring through hydrophobic interactions. In this study, we determined the amino acid (AA) residues of ApPrx crucial for forming the decamer using AA mutations. The ApPrx0Cys mutant, wherein all cysteine residues were mutated to serine, was prepared as a model protein to remove the influence of the redox states of the cysteines on its assembling behavior. The boundary between each homodimer of ApPrx0Cys contains characteristic aromatic AA residues forming hydrophobic interactions: F46, F80, W88, W210, and W211. We found that a single mutation of F46, F80, or W210 to alanine completely disassembled the ApPrx0Cys decamer to homodimers, which was clarified by gel‐filtration chromatography and dynamic light scattering measurements. F46A, F80A, and W210A mutants lacked only one aromatic ring compared with ApPrx0Cys, indicating that the assembly is very sensitive to the surface structure of the protein. X‐ray structures revealed two mechanisms of disassembly of the ApPrx decamer: loss of hydrophobicity between homodimers and flip of the arm domain. The AA residues targeted in this study are well conserved in ring‐type Prx proteins, suggesting the importance of these residues in the assembly. This study demonstrates the sensitivity and modifiability of peroxiredoxin assembly by a simple AA mutation.
Conditional median run length performance of the synthetic X¯ chart with unknown process parameters
Authors: Hu XueLong , Castagliola Philippe , Tang AnAn , Zhou XiaoJian , Zhou PanPan
Published: February 2020

Synthetic‐type charts are efficient tools for process monitoring. They are easy to design and implement in practice. The properties of these charts are usually evaluated under the assumption of known process parameters. This assumption is sometimes violated in practice, and process parameters have to be estimated from different phase I data sets collected by different practitioners. This fact causes the between‐practitioners variability among the properties of the synthetic‐type charts designed for each practitioner. In fact, the shape of the run length distribution of the synthetic‐type charts changes with the mean shift size. As a good alternative, the median run length
metric is argued to evaluate the properties of different control charts. In this paper, the
is used as a measure of the synthetic
chart's performance, and the conditional
properties of the synthetic
chart with unknown process parameters are investigated. Both the average
(
) and the standard deviation of
(
) are used together to investigate the chart's properties when the process parameters are unknown. If the available number of phase I samples is not large enough to reduce the variability of the in‐control
values to an acceptable level, a bootstrap‐type approach is suggested to adjust the control limits of the synthetic
chart and to further prevent many unwanted lower in‐control
values.
Survival model methods for analyses of cancer incidence trends in young adults
Authors: Yang Wan , Kehm Rebecca D. , Terry Mary Beth
Published: February 2020

Recent studies have reported increases in cancer incidence in adults under 50 years. However, there remains uncertainty about whether these are true increases or a result of incidental findings from increased medical imaging. To evaluate these trends, we propose an alternative method to age‐period‐cohort analyses based on survival modeling. Simulations show that our method is capable of quantifying cohort effects within various backgrounds including increasing medical imaging. We applied the method to analyze the changes in cancer incidence rates for 44 anatomic sites, stratified by sex, by birth cohort for individuals born from 1945 to 1969 in the US based on incidence data from the Surveillance, Epidemiology, and End Results (SEER) program, and tested the validity of our models using later birth cohorts (1970‐1974 and 1975‐1979). We found that cancer risks have increased significantly in 15 sites (9 in men and 11 in women) for 25‐49 year‐olds. These results were consistent with previous findings from age‐period‐cohort analyses. Furthermore, based on our simulations, these increases were independent of increased medical imaging and support substantial, increased extrinsic risks in the identified cancers. Although our approach has several limitations including the restriction to the younger age range and requirement of complete data for all ages of interest, we demonstrate many advantages of our approach including the ease in implementation and interpretation of cohort effects, robustness to various period backgrounds, and ability to make predictions. Our approach should help epidemiologists evaluate cohort effects using incidence data for cancer or other diseases.
Temperature‐Dependent Green Synthesis of New Series of Mannich Bases from 4‐Hydroxy‐pyridine‐2‐one and Their Antioxidant Activity Evaluation
Authors: Kamali Mahmood , Shahi Sahar , Mashhadi Akbar Bujar Masud
Published: February 2020

A novel class of bio‐based 4‐hydroxy‐2‐pyridones was synthesized via Mannich reaction under solvent free conditions in absence any catalyst at room temperature. Interestingly, in thermal condition, the yields of these products were decreased and others products (from condensation of two molecules of 2‐pyridone and one molecule of aldehyde) were obtained. Then the antioxidant activity of the synthesized compounds were evaluated by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay methods. In general all of products showed significant radical scavenging potential, but the derivatives of pyrrolidine were more significant effective than the piperidine derivatives. This protocol provides a convenient, room temperature, solvent‐free, and catalyst‐free access to new 3‐substituted‐4‐hydroxy‐2‐pyridones.
2D Single‐Atom Catalyst with Optimized Iron Sites Produced by Thermal Melting of Metal–Organic Frameworks for Oxygen Reduction Reaction
Authors: Liu Dong , Li Jin‐Cheng , Ding Shichao , Lyu Zhaoyuan , Feng Shuo , Tian Hangyu , Huyan Chenxi , Xu Mingjie , Li Tao , Du Dan , Liu Peng , Shao Minhua , Lin Yuehe
Published: February 2020

Zeolitic‐imidazolate‐frameworks‐8 (ZIF‐8) derivatives have recently been demonstrated as one of the most ideal precursors to prepare single‐atom metal catalysts for oxygen reduction reaction (ORR). However, abundant single‐atom metal sites are buried in the derived carbon nanoparticles, rendering them useless for ORR. Here a novel ZIF‐8 “thermal melting” strategy is proposed to prepare a high specific surface area of Fe‐N‐doped graphene nanosheets (Fe‐N/GNs) with single‐atom Fe‐sites on the surface which are accessible to electrolytes, optimizing their utilization and improving ORR activity. As a result, the Fe‐N/GNs material exhibits excellent ORR activity with half‐wave potentials of 0.903 V in alkaline media and 0.837 V in acidic media, which are comparable to commercial Pt/C catalysts.
A Novel Synthesis Yielding Macroporous CaFe2O4 Sponges for Solar Energy Conversion
Authors: Bloesser André , Timm Jana , Kurz Hannah , Milius Wolfgang , Hayama Shusaku , Breu Josef , Weber Birgit , Marschall Roland
Published: February 2020

Phase‐pure and highly crystalline CaFe2O4 with a sponge‐like macroporous structure is synthesized for the first time via facile solution‐based microwave reaction and subsequent short thermal treatment. The formation mechanism of the orthorhombic phase (Pnma) and the pore network is investigated in detail and reveals a complex formation of this p‐type semiconductor. Superconducting quantum interference device (SQUID) magnetometry and Mössbauer spectroscopy confirm the phase changes by altered magnetic properties. Furthermore, the optical and photoelectrochemical properties of the material were investigated. The material has a bandgap of 1.9 eV and sufficient band positions for water splitting. Valence‐to‐core X‐ray emission spectroscopy is used to support the band positions obtained from Mott–Schottky analysis. Photocathodes prepared from macroporous CaFe2O4 generate photocurrents under illumination with light of up to 600 nm.
How to build a thought
Authors: Rasmussen Joshua , Bailey Andrew M. ,   Philosophy Documentation Center
Published: February 2020

We uncover a surprising discovery about the basis of thoughts. We begin by giving some plausible axioms about thoughts and their grounds. We then deduce a theorem, which has dramatic ramifications for the basis of all thoughts. The theorem implies that thoughts cannot come deterministically from any purely “thoughtless” states. We expect this result to be too dramatic for many philosophers. Hence, we proceed to investigate the prospect of giving up the axioms. We show that each axiom's negation itself has dramatic consequences that should be of interest to philosophers of mind. Our proof of the theorem provides a new guiderail for thinking about the nature and origin of thoughts.
A simple improvement of a tip loss model for actuator disc simulations
Authors: Pirrung Georg Raimund , van der Laan Maarten Paul , Ramos‐García Néstor , Meyer Forsting Alexander Raul
Published: February 2020

The loading of a wind turbine decreases towards the blade tip because of the velocities induced by the tip vortex. This tip loss effect has to be taken into account when performing actuator disc simulations, where the single blades of the turbine are not modeled. A widely used method applies a factor on the axial and tangential loading of the turbine. This factor decreases when approaching the blade tip. It has been shown that the factor should be different for the axial and tangential loading of the turbine to model the rotation of the resulting force vector at the airfoil sections caused by the induced velocity. The present article contains the derivation of a simple correction for the tangential load factor that takes this rotation into account. The correction does not need any additional curve fitting but just depends on the local airfoil characteristics and angle of attack. Actuator disc computations with the modified tip loss correction show improved agreement with results from actuator line, free wake lifting line, and blade element momentum simulations.
Liver gene regulatory networks: Contributing factors to nonalcoholic fatty liver disease
Authors: Cebola Inês
Published: February 2020

Metabolic diseases such as nonalcoholic fatty liver disease (NAFLD) result from complex interactions between intrinsic and extrinsic factors, including genetics and exposure to obesogenic environments. These risk factors converge in aberrant gene expression patterns in the liver, which are underlined by altered cis‐regulatory networks. In homeostasis and in disease states, liver cis‐regulatory networks are established by coordinated action of liver‐enriched transcription factors (TFs), which define enhancer landscapes, activating broad gene programs with spatiotemporal resolution. Recent advances in DNA sequencing have dramatically expanded our ability to map active transcripts, enhancers and TF cistromes, and to define the 3D chromatin topology that contains these elements. Deployment of these technologies has allowed investigation of the molecular processes that regulate liver development and metabolic homeostasis. Moreover, genomic studies of NAFLD patients and NAFLD models have demonstrated that the liver undergoes pervasive regulatory rewiring in NAFLD, which is reflected by aberrant gene expression profiles. We have therefore achieved an unprecedented level of detail in the understanding of liver cis‐regulatory networks, particularly in physiological conditions. Future studies should aim to map active regulatory elements with added levels of resolution, addressing how the chromatin landscapes of different cell lineages contribute to and are altered in NAFLD and NAFLD‐associated metabolic states. Such efforts would provide additional clues into the molecular factors that trigger this disease.

This article is categorized under:

Biological Mechanisms > Metabolism

Biological Mechanisms > Regulatory Biology

Laboratory Methods and Technologies > Genetic/Genomic Methods
Breeding biology of the Helmeted Manakin Antilophia galeata in an ecotone between the Atlantic Forest and the Cerrado
Authors: de Marçal Bráulio Freitas , Lopes Leonardo Esteves
Published: February 2020

Manakins (Pipridae) are well-known by their promiscuous mating system. Nonetheless, scarce evidence suggests that the Helmeted ManakinAntilophia galeata, the only dichromatic manakin widely distributed in the South American Cerrado, is monogamic. We studied the breeding biology of the Helmeted Manakin in the state of Minas Gerais, southeastern Brazil. We found 17 nests, which are built in the forest undergrowth (usually below 3 m height). Nests are a cup attached by its top lip usually in the angle of a forked branch. The nest attachment zone is made mostly of spider silk. The structural zone is constructed with dry broad leaves, leaf petioles and horsehair fungus, which were bind together by a considerable amount of spider silk. The outer (decorative) zone is made with some hanging dry broad leaves, frequently forming a tail. Clutch size is always two (n= 12), and eggs are long oval, with a ground color in different shades of beige, marked with irregular spot, blotches and, sometimes, streaks ranging from light to dark brown. Mean eggs measurements were 23.9 x 16.3 mm (n= 14), weighting 3.3 g (n= 10). Eggs are laid once each day and hatching is synchronous. Females are the sole responsible for nest building (which usually took 10 days), incubation (18.5 days), and nestling care (18.3 days). The simple percentage of successful nests (n= 11) was 27% and predation was the main cause of nest failure. The breeding season extends from the second half of August to the first half of January. Renesting after loss of a first clutch is a common strategy and we recorded up to three nesting attempts for a single female. We present evidence that the Helmeted Manakin is promiscuous, as usual for a dichromatic manakin.
Diet of the Bobolink (Dolichonyx oryzivorus) in rice fields on its wintering grounds in Argentina
Authors: Lorenzón Rodrigo E. , Antoniazzi Carolina E. , Fabre Franco N. , Quiroga Virginia M. , Regner Silvia A. , Ronchi-Virgolini Ana L. , Olguin Pamela F. , Leon Evelina J. , Beltzer Adolfo H.
Published: February 2020

Winter diet of Bobolinks (Dolichonyx oryzivorus), a bird considered a pest of rice fields, is known to consist primarily of seeds. However, it is not yet possible to establish the extent to which non-rice plants and animal components contribute to its diet. To contribute to these issues, we studied the diet of the Bobolink found in rice fields on its wintering grounds in Santa Fe, Argentina, to provide information on (i) the composition of the diet and (ii) the relative importance of plant and animal components in the diet and of the different prey categories. We captured Bobolinks with mist nets and obtained samples of stomach contents by warm water and emetic-based regurgitation to determine the composition of the diet (n = 46 samples) and the importance of the different prey (n = 25 samples), mainly during March, just prior to northbound migration. We confirmed that the Bobolink’s diet in this region during this period is predominantly herbivorous (97%) and rice-based (55%), although it also consumes a large number of seeds of non-cultivated plants that represented 42% of the diet. Invertebrates, although of less importance than plant components (3%), had been consumed by 97% of captured individuais. Our results document the importance of non-cultivated plants and animal prey in the diet of Bobolinks in addition to rice.
Bird-epiphyte interactions in three Atlantic Forest environments in southeastern Brazil
Authors: Boechat Rafael Ferreira , da Silva Bianca Ferreira , Nunes-Freitas André Felippe
Published: February 2020

Epiphytes reach up to 67% of the total plant species richness in some tropical areas and act as diverse food resources that can be crucial in times of food scarcity. The avifauna assists in their reproduction, either through pollination or seed dispersal, thus creating a vast interaction spectrum between both communities within a continuous ecological process. Few scientific studies concerning avian and epiphytic community interactions are available and not much is known on their specific relationships. However, their absence can change existing ecological processes in habitats. With this in mind, a study undertaken at the Reserva Ecológica do Guapiaçu, Cachoeiras de Macacu, RJ analyzed bird and epiphytic interactions in three different environments: forest, fragmented forest and pastureland. The aim was to study how these interactions can vary according to their degree of conservation and successional stage. Three observation points were marked in a forest, nine points in forest fragments and ten observation points in the pastureland, thus providing a total of 1056 observation hours. As a result, 643 avian and epiphytic interactions were registered. We tested differences in the number of interactions between the areas. The initial hypothesis was that the largest number of registered interactions would occur in the preserved forest given its preserved state and existing biodiversity; however, the pasture area presented the highest number and variety of interactions. Most of the birds observed in the different habitats presented a high interaction in pasture areas where resource availability is reduced, making epiphytes an important food supply. Epiphytes permit a valuable network of interactions by attracting a high diversity of birds, especially those that disperse fruit or pollinate flowers, illustrating their importance within a degraded environment.
Hybridization between Yellow-billed Cardinal Paroaria capitata and Red-crested Cardinal P. coronata in southern Argentina
Authors: Segura Luciano N. , De Maio Federico A. , Failla Mauricio
Published: February 2020

The genus Paroaria is a group of conspicuous songbirds widely distributed in South America that has been studied recently to delimit its species and establish their phylogenetic relationships. Although hybridization has been reported between the most phylogenetically related species of the genus, we here present a case of hybridization between the Yellow-billed Cardinal (P. capitata) and Red-crested Cardinal (P. coronata) for the first time, two phylogenetically unrelated members of the group. This data contributes to the knowledge of this avian group whose systematics is still under debate.
First documented record of Cerulean Warbler Setophaga cerulea (Parulidae) in Brazil
Authors: de Farias Fernando Bittencourt , Dalpaz Larissa
Published: February 2020

Cerulean Warbler (Setophaga cerulea; Parulidae) is a “Vulnerable” species which breeds in North America and migrates to winter in South America. Here we present the first documented record of the species in Brazil. One male was photographed foraging in the canopy of secondary forest on Santa Catarina island, south Brazil, on 07 April 2018. At the time of the record the species was expected to be on migration north to North America. Since the individual was heading south it is assumed that it was lost. This record can then be potentially explained by the vagrancy theory of reverse migrants.
Evidence of breeding activity of subadult Turdus thrushes in Argentina
Authors: Barboza Exequiel , Capllonch Patricia , Ortiz Fernando Diego , Jahn Alex E.
Published: February 2020

Little is known about the age at which many Neotropical bird species first attempt to breed. We evaluated the breeding condition of 515 adult and subadult males and females among four species ofTurdusthrushes (T. nigriceps, T. chiguanco, T. amaurochalinusandT. rufiventris) in Tucumán, Argentina during three breeding seasons (2015 to 2018). We registered a total of 126 individuals with brood patches and cloacal protuberances, which accounted for 24.5% of thrushes in breeding condition that we sampled. Forty thrushes had a brood patch (31.7% of those in breeding condition), of which 11 were subadults (8.7%). Eighty-six thrushes (68.3%) had a swollen cloacal protuberance, 18 of which were subadults (14.3%). Only a few of the subadults in breeding condition built nests, incubated eggs or raised nestlings. Of 130 nests we found, only 3 belonged to a subadult thrush (in all cases, a subadult female with an adult social mate), one of which was successful. Further research on these patterns among various Neotropical bird species could lead to important insights into the life history strategies that characterize different populations, and how these ultimately affect their population dynamics.
Reproductive behavior of White-tailed Kites (Elanus leucurus) in the Pampas of Argentina
Authors: Baladrón Alejandro V. , Cavalli Matilde , Pretelli Matías G. , Bó María S.
Published: February 2020

The White-tailed Kite (Elanus leucurus) is a raptor that has been less studied in the Neotropics than in the Nearctic region, especially in relation to its reproductive behavior. In this study, we report information about the phenology and activity patterns of this raptor at the Pampas of Argentina. We found that White-tailed Kites have a prolonged breeding season, from October to May. Time-activity budgets of mating pairs indicated a pronounced division of roles in parental care between sexes. Females devoted most of their time to nest construction, incubation and chick care (80% of total time) and males to food provisioning and vigilance (70% of total time). We registered 11 cases of prey transfer from the male to the female. In four cases the transfer occurred in flight and in the remaining seven cases while individuals were perched. Our results agree with general patterns on breeding behavior of White-tailed Kites from North America, suggesting a consistent behavioral pattern throughout the species’ distribution.
Nesting information for Tropeiro Seedeater (Sporophila beltoni), an endemic songbird from southern Brazil
Authors: Repenning Márcio , Fontana Carla Suertegaray
Published: February 2020

We present the first nesting information for the Tropeiro Seedeater (Sporophila beltoni), a newly described and poorly known Neotropical passerine endemic to southern Brazil. We observed a novel male biased behavior for nest site selection in the Tropeiro Seedeater based on seven events of pre-nesting display courtship. We describe the nest, eggs, nestlings, and fledglings based on 133 nests found over four breeding seasons (2007 to 2011). The nest is a cup-shaped structure made with dry grass inflorescences and spider webs. It is placed in low, forked branches of substrate shrubs and contains multiple attachment points. The eggs are typically white with dark spots or stripes, and are pyriform in shape. Average egg dimensions are 18.2 × 13.2 mm. Nestlings fledge after 10 days. We provide the key information for distinguishing the nest, eggs, nestlings and fledglings of S. beltoni from other sympatric Sporophila species.
First observations of the diet of the Pearl Kite (Gampsonyx swainsonii magnus) in southwestern Ecuador
Authors: Orihuela-Torres Adrian , Brito Jorge , Pérez-García Juan Manuel
Published: February 2020

We describe the diet of Pearl Kite (Gampsonyx swainsonii magnus) by pellet analysis collected in an active nest in southwest Ecuador in May 2018. Reptiles were the most consumed taxonomic group both in frequency of occurrence (FO = 46.4%) and in biomass (B = 59.8%), followed by birds (FO = 33.9% and B = 38.3%) and insects (FO = 19.6% and B = 1.8%). Our results showed Pearl Kite as a generalist raptor but with a higher consumption of reptiles, which is according with previous studies in other areas where other subspecies inhabit, despite this subspecies showed a higher consumption of birds. Despite the low sample size, this study is interesting as it is the first one on the diet of the Pearl Kite for Ecuador and also for this subspecies. Basic studies on the trophic ecology of Neotropical raptors such as this are needed. For this reason we encourage further studies to fill existing gaps in knowledge and improve effective long-term conservation strategies.