bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of checkpoint kinase 1 inhibition by prexasertib on the tumor immune microenvironment of head and neck squamous cell carcinoma
Authors: Chaudhary Ritu , Slebos Robbert J. C. , Song Feifei , McCleary‐Sharpe Keegan P. , Masannat Jude , Tan Aik Choon , Wang Xuefeng , Amaladas Nelusha , Wu Wenjuan , Hall Gerald E. , Conejo‐Garcia Jose R. , Hernandez‐Prera Juan C. , Chung Christine H.
Published: December 2020

Prognosis for patients with recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC) remains poor. Development of more effective and less toxic targeted therapies is necessary for HNSCC patients. Checkpoint kinase 1 (CHK1) plays a vital role in cell cycle regulation and is a promising therapeutic target in HNSCC. Prexasertib, a CHK1 inhibitor, induces DNA damage and cell death, however, its effect on the tumor immune microenvironment (TIME) is largely unknown. Therefore, we evaluated a short‐term and long‐term effects of prexasertib in HNSCC and its TIME. Prexasertib caused increased DNA damage and cell death in vitro and significant tumor regression and improved survival in vivo. The gene expression and multiplex immunohistochemistry (mIHC) analyses of the in vivo tumors demonstrated increased expression of genes that are related to T‐cell activation and increased immune cell trafficking, and decreased expression of genes that related to immunosuppression. However, increased expression of genes related to immunosuppression emerged over time suggesting evasion of immune surveillances. These findings in gene expression analyses were confirmed using mIHC which showed differential modulation of TIME in the tumor margins and as well as cores over time. These results suggest that evasion of immune surveillance, at least in part, may contribute to the acquired resistance to prexasertib in HNSCC.
Black Tea Theaflavin Detoxifies Metabolic Toxins in the Intestinal Tract of Mice
Authors: Zhang Shuwei , Ohland Christina , Jobin Christian , Sang Shengmin
Published: December 2020

Scope

This study is to determine the in vivo efficacy of black tea theaflavin (TF) to detoxify two metabolic toxins, ammonia and methylglyoxal (MGO), in mice

Methods and results

Under in vitro conditions, TF is able to react with ammonia, MGO, and hydrogen peroxide to produce its aminated, MGO conjugated, and oxidized products, respectively. In TF‐treated mice, the aminated TF, the MGO conjugates of TF and aminated TF, and the oxidized TF are searched using LC‐MS/MS. The results provide the first in vivo evidence that the unabsorbed TF is able to trap ammonia to form the aminated TF; furthermore, both TF and the aminated TF have the capacity to trap MGO to generate the corresponding mono‐MGO conjugates. Moreover, TF is oxidized to dehydrotheaflavin, which underwent further amination in the gut. By exposing TF to germ‐free (GF) mice and conventionalized mice (GF mice colonized with specific‐pathogen‐free microbiota), the gut microbiota is demonstrated to facilitate the amination and MGO conjugation of TF.

Conclusion

TF has the capacity to remove the endogenous metabolic toxins through oxidation, amination, and MGO conjugation in the intestinal tract, which can potentially explain why TF still generates in vivo efficacy while showing a poor systematic bioavailability.
Fiber sensor based on Fabry‐Perot/Mach‐Zehnder hybrid interferometer for transverse load and temperature
Authors: Han Yang , Liu Bo , Wu Yongfeng , Mao Yaya , Zhao Lilong , Sun Tingting , Nan Tong , Wang Jin , Tang Rong
Published: December 2020

A fiber optic sensor based on array of silica microspheres and air cavity have been fabricated in fusion splicer and experimentally demonstrated in this article. The four‐microspheres structure stimulates higher‐order cladding modes of the gaussian beam, and the air cavity acts as a coupler for Mach‐Zehnder interferometer (MZI) on the one hand and a Fabry‐Perot interferometer (FPI) on the other. The sensing head is subjected to temperature and transverse load where the sensitivity of 160 pm/°C and 124.6 pm/N are obtained, respectively. Compared with similar sensors, the sensor has the advantages of high sensitivity, low‐cost and practical, and it will have a great market prospect.
A novel and compact 3.5 GHz tunable bandpass filter in SIW technology with shunt‐inductive discontinuities switched by pin diode switches
Authors: Caleffo Ricardo Caranicola , Correra Fatima Salete
Published: December 2020

This article presents a novel tunable bandpass filter designed in substrate integrated waveguide (SIW) technology to operate at 3.5 GHz, a frequency widely used in 5G and WiMAX systems. The bandpass filter uses shunt‐inductive discontinuities provided by a novel offset post arrangement that resulted in a compact filter. The filter bandwidth is tunable through PIN diode switches connected to the metal posts, allowing three different operation states. The novel tunable filter was fabricated and demonstrated bandwidths of 6.23% and 0.714% centered at 3.5 GHz, with low insertion losses. The measured results are in good agreement with full‐wave simulation results.
Hunting for the perfect test: Neuromuscular diagnosis in the age of genomic bounty
Authors: Estrella Elicia A. , Kang Peter B.
Published: December 2020

See article on pages 304–310 in this issue.
COL6A1 related muscular dystrophy in Landseer dogs: A canine model for Ullrich congenital muscular dystrophy
Authors: Brands Jan , Steffen Frank , Spennes Jochen , Leeb Tosso , Bilzer Thomas
Published: December 2020

Background

Collagen VI related myopathies are congenital diseases of variable phenotype. The severe phenotype is referred to as Ullrich congenital muscular dystrophy. In this study, we describe analoguos clinical signs and histopathological alterations in Landseer dogs.

Materials

We collected clinical data from two affected dogs and investigated the neuromuscular changes in five dogs from two different litters with immunohistochemistry and immunofluorescence. All affected dogs were homozygous for the p.Glu97* nonsense variant in the COL6A1 gene encoding the alpha‐1 chain of collagen VI.

Results

Muscle biopsies revealed alterations similar to those in human patients with Ullrich congenital muscular dystrophy including the virtual absence of collagen VI in skeletal muscles.

Conclusions

The clinical and pathological characterization of the affected Landseer dogs enhances the value of this animal model for human Ullrich congenital muscular dystrophy.
Neuromuscular ultrasound competency assessment: Consensus‐based survey
Authors: Tawfik Eman A. , Cartwright Michael S. , Grimm Alexander , Boon Andrea J. , Kerasnoudis Antonios , Preston David C. , Wilder‐Smith Einar , Axer Hubertus , Hobson‐Webb Lisa D. , van Alfen Nens , Crump Nicholas , Shahrizaila Nortina , Inkpen Peter , Mandeville Ross , Sakamuri Sarada , Shook Steven J , Shin Susan , Walker Francis O.
Published: December 2020

Neuromuscular ultrasound is a rapidly evolving specialty with direct application for patient care. Competency assessment is an essential standard needed to ensure quality for practitioners, particularly for those newly acquiring skills with the technique. Our aim was to survey experts' opinions regarding physician competency assessment of neuromuscular ultrasound and to identify minimal competency of knowledge and skills. The opinions of 18 experts were obtained through the Delphi method using two consecutive electronic surveys. A high degree of consensus was achieved on items regarding framework and the conduct of neuromuscular ultrasound assessment and the knowledge and skills that a candidate needs to attain minimal competency in neuromuscular ultrasound. In this study, a group of neuromuscular ultrasound experts developed a general framework for neuromuscular ultrasound competency assessment and recommended testable areas of knowledge and skills suitable for establishing minimal competency.
Nitrogen‐doped porous biomass carbon with ultrastable performance as anodes for potassium‐ion batteries
Authors: Zhang Yi , Huang Zongwang , Zhang Haimin , Zhang Qiang , Zhang Jun , Pan Anqiang , Cai Zhenyang , Liu Sainan
Published: December 2020

The potential safety hazards and limited lithium resources of lithium‐ion batteries (LIBs) have restricted their practical application. Potassium‐ion batteries (KIBs) are a novel energy storage technology with great cost advantages and are a promising alternative to LIBs. However, because of the large ionic radius of K+, the common anode materials used in LIBs exhibit a large volumetric expansion and structural collapse in the process of charging and discharging in a KIB. In this work, the prepared nitrogen‐doped porous carbon fibers (P‐CFs) from bombyx mori silk cocoons via a simple KCl activation and high‐temperature carbonization method. The P‐CFs possess a large specific surface area and one‐dimensional porous structure, offering facile storage and fast transport channels for K+ ions. When used as an anode for KIBs, the P‐CFs exhibit a high reversible specific capacity of 275 mAh·g−1 at a current density of 0.1 A·g−1 after 500 cycles and even retain a capacity of 100 mAh·g−1 after 5000 cycles at 2 A·g−1. This study demonstrates a simple strategy for the low‐cost synthesis of nitrogen‐doped porous carbon fibers from an environmental friendly biomaterial, with excellent electrochemical performance as an anode for KIBs.
Rapid template‐guided ligand‐free synthesis of ultrasmall Pt nanoclusters with efficient hydrogen evolution reaction activity and their versatile release
Authors: Chen Lizhen , Azeem Shoaib , Ruan Mingbo , Xu Weilin , Barck Almut , Kornowski Andreas , Parak Wolfgang J. , Chakraborty Indranath
Published: December 2020

The design of ligand‐free platinum nanoclusters (PtNCs) for the field of renewable energy is still challenging. Herein, we reported a fast synthesis of ligand‐free Pt nanoclusters (NCs) by utilizing the outer defect of a representative type of zeolitic imidazolate framework (ZIF). Structural investigation suggests a homogenous distribution of the PtNCs on the outer layer of the ZIF‐8 structure. The as‐prepared PtNCs@ZIF‐8 exhibits high catalytic activity for the hydrogen evolution reaction (HER). The extremely low overpotential with 1.4 mV, high kinetic current (specific and mass activity at 50 mV), and larger exchange current density were achieved in acidic solution, better than those of the commercial 20% Pt/C catalysts under the same condition. Furthermore, the PtNCs can be extracted from the ZIF‐8 structure to both aqueous and non‐aqueous solvent, which could be further used for other systems. These findings allow for a simple route of template‐guided NC synthesis and their release.
Expectancy–value theory as a framework to understand the relation between domain‐specific perfectionism and internalizing symptoms in freshman high school students
Authors: Koerten Hannah R. , Dubow Eric F.
Published: December 2020

This study explored how domain‐specific perfectionism (academic, social, physical appearance) among high school freshmen relates to internalizing symptoms using critical elements of expectancy–value theory (i.e., domain value and competence) as moderators. Results indicate that perfectionism across all domains was positively and significantly related to internalizing symptoms. Within the social domain, social value was a significant moderator of the relation between perfectionism and internalizing symptoms, and perceived social competence was a significant moderator of that moderation effect (i.e., at higher levels of social value and lower levels of perceived social competence, the relation between perfectionism and internalizing symptoms was the strongest). These findings provide support for the use of the expectancy–value model to predict mental health symptoms in the social domain and suggest the importance of addressing domain‐specific perfectionism in the schools.
Azithromycin for preventing bronchopulmonary dysplasia in preterm infants: A systematic review and meta‐analysis
Authors: Razak Abdul , Alshehri Norah
Published: December 2020

Context

Azithromycin has anti‐Ureaplasma and anti‐inflammatory properties that might help reduce lung injury in preterm infants.

Objective

To test the efficacy and safety of prophylactic or therapeutic azithromycin in preventing bronchopulmonary dysplasia (BPD) in preterm infants with unknown or proven Ureaplasma status.

Methods

We searched PubMed, Web of Science, and Cochrane Library until 13 September 2020. Two authors independently assessed the eligibility, risk of bias, and extracted the data. We performed a random‐effects model meta‐analysis to yield pooled relative risk (RR) or mean difference (MD) with 95% confidence interval (CI). We used the Cochrane GRADE methodology for summarizing the results.

Results

We included five randomized clinical trials. The meta‐analysis revealed no significant differences in BPD (RR, 0.92; 95% CI, 0.71, 1.19; low‐quality evidence), death (RR, 0.75; 95% CI, 0.52, 1.10; low‐quality evidence), and BPD or death (RR, 0.90; 95% CI, 0.74, 1.10; low‐quality evidence). However, a significantly lower BPD or death (RR, 0.83; 95% CI, 0.70, 0.99) and a trend toward lower BPD (RR, 0.83; 95% CI, 0.66, 1.03) with azithromycin therapy was noted in Ureoplasma positive neonates. No differences in secondary outcomes were noted, except for significantly lower supplemental oxygen days with azithromycin (MD, −6.06; 95% CI, −7.40, −4.72; moderate‐quality evidence). The test for subgroup differences between short (<7 days) and long (>7 days) course of azithromycin were nonsignificant for all the outcomes.

Conclusion

Low‐quality evidence suggests azithromycin therapy reduces BPD or death in preterm infants with positive Ureoplasma, but not in all preterm infants.
The Remarkable Anisotropic Compressibility and Metallic CrCr Chains in Topological Semimetal CrP4 under High Pressure
Authors: Li Chunyu , Liu Xiaolei , Yu Zhenhai , Wu Wei , Zhang Lili , Zhou Chunyin , Zhao Jinggeng , Guo Yanfeng , Luo Jianlin
Published: December 2020

Metal tetraphosphides (MP4, M = 3d transition metals) exhibit the layered‐structure character, in which the metal atom chains are sandwiched between the P42− layers, and have attracted considerable interest due to the outstanding physical and chemical properties, such as good electrical conductivity and high lithium capacity. Herein, the CrP4 single crystal is prepared using the high‐pressure and high‐temperature method via the 2000 ton Kawai‐type multianvil apparatus at ShanghaiTech University (SHTech‐2000). The structural modification under high pressure is investigated by synchrotron X‐ray diffraction combined with diamond anvil cell techniques. CrP4 shows remarkable axial anisotropic compressibility, in which the c‐axis is more compressible than a‐ and b‐axes. The formation of infinite chains of CrCr metallic bonding in CrP4 under high pressure enhances the electrical conductivity.
Regulation of Magnetic Phase Transition and Magnetocaloric Effect of DyCo2−xCrx Compounds
Authors: Chen Wang , Ma Lei , Lu Shifan , Xiong Jiacai , Li Lin , Wang Jiang , Rao Guanghui
Published: December 2020

The magnetic phase transition, magnetic and magnetocaloric effect of DyCo2−xCrx (x = 0.0–0.2) compounds have been studied. X‐ray diffraction (XRD) data show that the main phases of DyCo2−xCrx compounds are MgCu2‐type cubic crystal structure, and the maximum atomic concentration of Cr in DyCo2 is 5%. With the x changed from 0.0 to 0.2, both of the lattice parameter and cell volume increased, and the coercivity at 10 K increased from 890 to 2839 Oe. With the introduction of Cr atoms, the type of magnetic phase transition can be regulated from the first order to the second order. Under a 5 T magnetic field, the maximum magnetic entropy changes (ΔSM) of DyCo2−xCrx (x = 0.0, 0.1, and 0.2) compounds are 10.4, 8.4, and 6.8 J kg−1 K−1, respectively, but the relative cooling power (RCP) actually increases, with values of 290.6, 312.5, and 396.7 J kg−1 respectively, which is because the width at half‐maximum of the ΔSM peak (δTFWHM) is increased.
Crystalline Sb2Te3: Side Surfaces and Disappearance of Dirac Cones
Authors: Kolobov Alexander V. , Fons Paul , Saito Yuta
Published: December 2020

Sb2Te3 is an end point of quasibinary GeTe–Sb2Te3 phase‐change alloys and also a prototypical topological insulator (TI). TIs are materials that behave like insulators in their interior but whose surfaces are characterized by metallic states with linear dispersion, the so‐called Dirac cones. Such surface states are symmetry protected, robust, and are maintained even in the presence of surface defects. It has been tacitly implied that any surfaces of a TI possess this property. Herein, using ab initio simulations, it is demonstrated that cleaving Sb2Te3 along certain side surfaces may lead to the disappearance of Dirac surface states. In particular, it is shown that the (110) surface of the typical TI Sb2Te3 is slightly gapped, whereas the () surface is metallic. The significance and potential benefits of the obtained results for practical applications in planar devices and memory cells are discussed.
Deep learning for inverse problems in quantum mechanics
Authors: Lantz Victor , Abiri Najmeh , Carlsson Gillis , Pistol Mats‐Erik
Published: December 2020

Inverse problems are important in quantum mechanics and involve such questions as finding which potential give a certain spectrum or which arrangement of atoms give certain properties to a molecule or solid. Inverse problems are typically very hard to solve and tend to be very compute intense. We here show that neural networks can easily solve inverse problems in quantum mechanics. It is known that a neural network can compute the spectrum of a given potential, a result which we reproduce. We find that the (much harder) inverse problem of computing the correct potential that gives a prescribed spectrum is equally easy for a neural network. We extend previous work where neural networks were used to find the electronic many‐particle density given a potential by considering the inverse problem. That is, we show that neural networks can compute the potential that gives a prescribed many‐electron density.
A dissipativity‐based model predictive control algorithm for power flow systems with equilibrium‐independent stability guaranteed
Authors: He Ye , Li Shaoyuan
Published: December 2020

This article presents a distributed model predictive control algorithm for power flow systems that can maintain overall stability when the system equilibrium configuration changes. The dynamics of the large‐scale power flow systems can be described by transportation, conversion, and storage of energy among and across subsystems. By strategically choosing the output for each subsystem and augmenting each local model predictive controller with a special passivity‐incremental constraint, the equilibrium‐independent dissipativity property of each closed‐loop subsystem can be guaranteed. The dissipativity‐preserving coupling between subsystems in the power flow system can be utilized to maintain equilibrium‐independent dissipativity and stability of the overall system. Simulation results of a fluid tank system with a changing equilibrium configuration show the effectiveness of the proposed algorithm.
Fog computing security and privacy for the Internet of Thing applications: State‐of‐the‐art
Authors: Alzoubi Yehia I. , Osmanaj Valmira H. , Jaradat Ashraf , Al‐Ahmad Ahmad
Published: December 2020

Fog nodes are implemented near to end‐users Internet of Things (IoT) devices, which mitigate the impact of low latency, location awareness, and geographic distribution unsupported features of many IoT applications. Moreover, Fog computing decreases the data offload into the Cloud, which decreases the response time. Despite these benefits, Fog computing faces many challenges in meeting security and privacy requirements. These challenges occur due to the limitations of Fog computing resources. In fact, Fog computing may add new security and privacy issues. Although many papers have discussed the Fog security and privacy issues recently, most of these papers have discussed these issues at a very high level. This paper provides a comprehensive understanding of Fog privacy and security issue. In this survey, we review the literature on Fog computing to draw the state‐of‐the‐art of the security and privacy issues raised by Fog computing. The findings of this survey reveal that studying Fog computing is still in its infant stage. Many questions are yet to be answered to address the privacy and security challenges of Fog computing.
When will gradient methods converge to max‐margin classifier under ReLU models?
Authors: Xu Tengyu , Zhou Yi , Ji Kaiyi , Liang Yingbin
Published: December 2020

We study the implicit bias of gradient descent methods in solving a binary classification problem over a linearly separable data set. The classifier is described by a non‐linear ReLU model and the objective function adopts the exponential loss function. We first characterize the landscape of the loss function and show that there can exist spurious asymptotic local minima besides asymptotic global minima. We then show that gradient descent (GD) can converge to either a global or a local max‐margin direction or may diverge from the desired max‐margin direction in a general context. For stochastic gradient descent (SGD), we show that it converges in expectation to either the global or the local max‐margin direction if SGD converges. We further explore the implicit bias of these algorithms in learning a multineuron network under certain stationary conditions and show that the learned classifier maximizes the margins of each sample pattern partition under the ReLU activation.
Value and benefits of model‐based systems engineering (MBSE): Evidence from the literature
Authors: Henderson Kaitlin , Salado Alejandro
Published: December 2020

Traditional document‐based practices in systems engineering are being transitioned to model‐based ones. Adoption of model‐based systems engineering (MBSE) continues to grow in industry and government, and MBSE continues to be a major research theme in the systems engineering community. In fact, MBSE remains a central element in the International Council on Systems Engineering (INCOSE)’s vision for 2025. Examining systems engineering literature, this paper presents an assessment of the extent to which benefits and value of MBSE are supported by empirical evidence. A systematic review of research and practice papers in major systems engineering archival journals and conference proceedings was conducted. Evidence was categorized in four types, two of which inductively emerged from the results: measured, observed (without a formal measurement process), perceived (claimed without evidence), and backed by other references. Results indicate that two thirds of claimed MBSE benefits are only supported by perceived evidence, while only two papers reported measured evidence. The aggregate assessment presented in this paper indicates that claims about the value and benefits of MBSE are mainly based on expectation. We argue that evidence supporting the value and benefits of MBSE remains inconclusive.
Phylogenomics of the tropical plant family Ochnaceae using targeted enrichment of nuclear genes and 250+ taxa
Authors: Schneider Julio V. , Jungcurt Tanja , Cardoso Domingos , Amorim André Márcio , Töpel Mats , Andermann Tobias , Poncy Odile , Berberich Thomas , Zizka Georg
Published: December 2020

Targeted capture of nuclear genes increasingly contributes to unravelling phylogenetic relationships that hitherto remained unresolved because of limitations of traditional Sanger sequencing. In particular, the study of tropical plant families has been compromised because they often rely on highly degraded DNA obtained from herbarium specimens. One such example is the pantropical Ochnaceae, which comprises 33 genera and approximately 550 species, occurring mostly in savannas and moist tropical forests. Here, we developed a set of baits covering about 660,000 bp from 275 nuclear genes used for the targeted enrichment based on all but one genus and more than 250 species. Using this novel dataset, we resolved the phylogenetic backbone of Ochnaceae, including that of Ochninae, and we established new relationships. Most importantly, our findings highlight that the neotropical and palaeotropical taxa of Sauvagesia form independent clades, requiring the re‐erection of formerly separate genera. Ouratea and Ochna (both Ochninae), by far the most species‐rich genera and represented by 120 and 41 species, respectively, came out as monophyletic. In contrast, the third‐most species‐rich genus, Campylospermum, is polyphyletic in two distinct clades. Ouratea, the only neotropical genus of Ochninae, was sister to the five palaeotropical genera of this subtribe. The bait kit developed in this study proved to be particularly useful for unravelling relationships within Ochninae, which includes about two‐thirds of the species diversity in the family.
Biogeography of succulent spurges from Brazilian Seasonally Dry Tropical Forest (SDTF)
Authors: Hurbath Fernanda , Stubbs Rebecca L. , Cordeiro Inês , Cellinese Nico
Published: December 2020

Seasonally Dry Tropical Forests (SDTFs) are found scattered throughout the Neotropics, from northwestern Mexico to northern Argentina, and southwestern and eastern Brazil, with eastern Brazil having the largest and most isolated fragment of SDTF, known as Caatinga. Growing knowledge from dated phylogenies and ancestral reconstruction studies suggests that SDTF lineages are nested in geographically structured phylogenies with clades highly restricted to each disjunct patch. To address these hypotheses, we investigated the biogeographic history of Euphorbia sect. Brasilienses, a group of succulent spurges from eastern Brazil's SDTF. To this aim, we assembled a concatenated matrix from 126 accessions with four markers (302 sequences from previous studies and 19 newly generated): one nuclear (ITS1) and three plastid (matK, ndhF, trnL‐trnF) loci. Our results showed that clade Brasilienses and its sister group Stachydium diverged from a common ancestor during the Miocene around 16.5 Ma. Clade Stachydium was recovered with a mean crown age of 7.7 Ma, while clade Brasilienses was recovered as a relatively young group that started diversifying about 3.1 Ma. Biogeographic results showed that the ancestral range of the clade Stachydium + Brasilienses comprised the Andes and eastern Brazil's SDTF, therefore suggesting past connections between western and eastern South America. The ancestral range of clade Brasilienses was restricted to eastern Brazil SDTF, which contrasts with clade Stachydium, which was recovered with a broader ancestral range around Late Miocene. Our results suggest limited dispersal abilities, niche conservatisms and an origin for E. sect. Brasilienses pre‐dating the Pleistocene. By contributing to the understanding of the origin and diversification of this group of endemic spurges, our study provides insights into the history of this SDTF in eastern South America.
6,8‐Diprenylorobol induces apoptosis in human colon cancer cells via activation of intracellular reactive oxygen species and p53
Authors: Choi Yong Jun , Lee Jongsung , Ha Sang Hoon , Lee Han Ki , Lim Heui Min , Yu Seon‐Hak , Lee Chang Min , Nam Myeong Jin , Yang Yung‐Hun , Park Kyungmoon , Choi Youn Soo , Jang Kyu Yun , Park See‐Hyoung
Published: December 2020

6,8‐Diprenylorobol is a natural compound mainly found in Glycyrrhiza uralensis fisch and Maclura tricuspidata, which has been used traditionally as food and medicine in Asia. So far, the antiproliferative effect of 6,8‐diprenylorobol has not been studied yet in colon cancer. In this study, we aimed to evaluate the antiproliferative effects of 6,8‐diprenylorobol in LoVo and HCT15, two kinds of human colon cancer cells. 6,8‐Diprenylorobol inhibited the proliferation of LoVo and HCT15 cells in a dose‐ and time‐dependent manner. A 40 μM of 6,8‐diprenylorobol for 72 h reduced both of cell viability under 50%. After treatment of 6,8‐diprenylorobol (40 and 60 μM) for 72 h, late apoptotic cell portion in LoVo and HCT15 cells were 24, 70% and 13, 90%, respectively, which was confirmed by checking DNA fragmentation in both cells. Mechanistically, 6,8‐diprenylorobol activated p53 and its phosphorylated form (Ser15, Ser20, and Ser46) expression but suppressed Akt and mitogen‐activated protein kinases (MAPKs) phosphorylation in LoVo and HCT15 cells. Interestingly, 6,8‐diprenylorobol induced the generation of intracellular reactive oxygen species (ROS), which was attenuated with N‐acetyl cysteine (NAC) treatment. Compared to the control, 60 μM of 6,8‐diprenylorobol caused to increase ROS level to 210% in LoVo and HCT15, which was reduced into 161% and 124%, respectively with NAC. Furthermore, cell viability and apoptotic cell portion by 6,8‐diprenylorobol was recovered by incubation with NAC. Taken together, these results indicate that 6,8‐diprenylorobol has the potential antiproliferative effect against LoVo and HCT15 colon cancer cells through activation of p53 and generation of ROS.
Revisiting global trends in freshwater insect biodiversity: A reply
Authors: van Klink Roel , Bowler Diana E. , Gongalsky Konstantin B. , Chase Jonathan M.
Published: December 2020

Jähnig et al. make some useful points regarding the conclusions that can be drawn from our meta‐analysis; however, some issues require clarification. First, we never suggested that there was a globally increasing trend of freshwater insect abundances, but only spoke of an average increasing trend in the available data. We also did not suggest that freshwater quality has improved globally, but rather that documented improvements in water quality can explain at least some of the trends we observed. Second, as we acknowledged, our data are not a representative set of freshwater ecosystems around the world, but they are what is currently accessible. Third, there is indeed no doubt that changes in abundance or biomass need not correlate with changes in other aspects of biodiversity, such as species richness or functional composition. Our analysis was specifically focused on trends in community abundance/biomass because it has been the subject of recent study and speculation, and is a widely available metric in long‐term studies. To better understand the recent changes in freshwater insect assemblages, we encourage freshwater ecologists to further open their troves of data from countless long‐term monitoring schemes so that larger and more comprehensive syntheses can be undertaken.

This article is categorized under:

Water and Life > Conservation, Management, and Awareness
Revisiting global trends in freshwater insect biodiversity
Authors: Jähnig Sonja C. , Baranov Viktor , Altermatt Florian , Cranston Peter , Friedrichs‐Manthey Martin , Geist Juergen , He Fengzhi , Heino Jani , Hering Daniel , Hölker Franz , Jourdan Jonas , Kalinkat Gregor , Kiesel Jens , Leese Florian , Maasri Alain , Monaghan Michael T. , Schäfer Ralf B. , Tockner Klement , Tonkin Jonathan D. , Domisch Sami
Published: December 2020

A recent global meta‐analysis reported a decrease in terrestrial but increase in freshwater insect abundance and biomass (van Klink et al., Science 368, p. 417). The authors suggested that water quality has been improving, thereby challenging recent reports documenting drastic global declines in freshwater biodiversity. We raise two major concerns with the meta‐analysis and suggest that these account for the discrepancy with the declines reported elsewhere. First, total abundance and biomass alone are poor indicators of the status of freshwater insect assemblages, and the observed differences may well have been driven by the replacement of sensitive species with tolerant ones. Second, many of the datasets poorly represent global trends and reflect responses to local conditions or nonrandom site selection. We conclude that the results of the meta‐analysis should not be considered indicative of an overall improvement in the condition of freshwater ecosystems.

This article is categorized under:

Water and Life > Conservation, Management, and Awareness
Contesting the Neoliberal Discourse of the World Class University: ‘Digital Socialism’, Openness and Academic Publishing
Authors: Peters Michael A. , Besley Tina
Published: December 2020

The principal aim of this paper is to contest the neoliberal discourse of the World Class University (WCU). The first section provides an understanding of the concept of the WCU within the context of a global competitive model of the knowledge economy and contrasts it with the social-democratic model based on open science and education that also provides links between new modes of openness, academic publishing and the world journal architecture. The paper makes the case for ‘knowledge socialism’ that accurately depicts the greater communitarian moment of the sharing and participative academic economy based on peer-to-peer production, social innovation and collective intelligence. It instantiates the notion of knowledge as a global public good. Profound changes in the nature of technology has enabled a kind of ‘digital socialism’ which is clearly evident in the shift in political economy of academic publishing based Open Access, cOAlition S, and ‘Plan S’ (mandated in 2020) established by national research funding organisations in Europe with the support of the European Commission and the European Research Council (ERC). The social democratic alternative to neoliberalism and the WCU is a form of the sharing academic economy known as ‘knowledge socialism’. Universities need to share knowledge in the search for effective responses to pressing world problems of fragile global ecologies and the growing significance of technological unemployment. This is a model that proceeds from a very different set of economic and moral assumptions than the neoliberal knowledge economy and the WCU.
Deciphering the genetic and epidemiological landscape of mitochondrial DNA abundance
Authors: Hägg Sara , Jylhävä Juulia , Wang Yunzhang , Czene Kamila , Grassmann Felix
Published: December 2020

Mitochondrial (MT) dysfunction is a hallmark of aging and has been associated with most aging-related diseases as well as immunological processes. However, little is known about aging, lifestyle and genetic factors influencing mitochondrial DNA (mtDNA) abundance. In this study, mtDNA abundance was estimated from the weighted intensities of probes mapping to the MT genome in 295,150 participants from the UK Biobank. We found that the abundance of mtDNA was significantly elevated in women compared to men, was negatively correlated with advanced age, higher smoking exposure, greater body-mass index, higher frailty index as well as elevated red and white blood cell count and lower mortality. In addition, several biochemistry markers in blood-related to cholesterol metabolism, ion homeostasis and kidney function were found to be significantly associated with mtDNA abundance. By performing a genome-wide association study, we identified 50 independent regions genome-wide significantly associated with mtDNA abundance which harbour multiple genes involved in the immune system, cancer as well as mitochondrial function. Using mixed effects models, we estimated the SNP-heritability of mtDNA abundance to be around 8%. To investigate the consequence of altered mtDNA abundance, we performed a phenome-wide association study and found that mtDNA abundance is involved in risk for leukaemia, hematologic diseases as well as hypertension. Thus, estimating mtDNA abundance from genotyping arrays has the potential to provide novel insights into age- and disease-relevant processes, particularly those related to immunity and established mitochondrial functions.
Critically Charged Superfluid 4He Surface in Inhomogeneous Electric Fields
Authors: Möller Th. B. , Moroshkin P. , Kono K. , Scheer E. , Leiderer P.
Published: December 2020

We have studied the spatial distribution of charges trapped at the surface of superfluid helium in the inhomogeneous electric field of a metallic tip close to the liquid surface. The electrostatic pressure of the charges generates a deformation of the liquid surface, leading to a “hillock” (called “Taylor cone”) or “dimple”, depending on whether the tip is placed above or below the surface. We use finite element simulations for calculating the surface profile and the corresponding charge density in the vicinity of the tip. Typical electric fields E are in the range of a few kV/cm, the maximum equilibrium surface deformations have a height on the order of (but somewhat smaller than) the capillary length of liquid 4He (0.5 mm), and the maximum number density of elementary charges in a hillock or dimple, limited by an electrohydrodynamic instability, is some 1013 m−2. These results can be used to determine the charge density at a liquid helium surface from the measured surface profile. They also imply that inhomogeneous electric fields at a bulk helium surface do not allow one to increase the electron density substantially beyond the limit for a homogeneous field, and are therefore not feasible for reaching a density regime where surface state electrons are expected to show deviations from the classical behavior. Some alternative solutions are discussed.
Fleeting Agencies
Authors: Datta Arunima
Published: December 2020

Fleeting Agencies disrupts the male-dominated narratives by focusing on gendered patterns of migration and showing how South Asian women labour migrants engaged with the process of migration, interacted with other migrants and negotiated colonial laws. This is the first study of Indian coolie women in British Malaya to date. In exploring the politicization of labour migration trends and gender relations in the colonial plantation society in British Malaya, the author foregrounds how the migrant Indian 'coolie' women manipulated colonial legal and administrative perceptions of Indian women; their gender-prescriptive roles, relations within patriarchal marriage institutions, and even the emerging Indian national independence movement in India and Malaya. All this, to ensure their survival, escape from unfavourable relations and situations, and improve their lives. The book also introduces the concept of situational or fleeting agency, which contributes to further a nuanced understanding of agency in the lives of Indian coolie women.
Local and Nonlocal Impacts of Gaps on Submerged Canopy Flow
Authors: Chung Hayoon , Mandel Tracy , Zarama Francisco , Koseff Jeffrey R.
Published: December 2020

Although shear layers generated by submerged vegetation reach a steady state once production and dissipation are balanced within a canopy, shear layers found in gaps and after trailing edges of canopy patches are inherently different and thereby perturb the canopy's mean and turbulent fields. Experiments were conducted in a laboratory flume to study canopy systems in which two model patches of submerged, rigid cylinder arrays are interrupted by a gap of varying stream‐wise lengths. Results show that, consistent with past studies, gaps locally enhance turbulence. However, this perturbation does not remain “local” within the gap, instead introducing enhanced turbulent energies throughout the water column that are transported downstream and thereby perturb the canopy flow. The study suggests a scaling, , which compares the eddy turnover time of the turbulence produced by the gap to the advection time downstream the second patch, that can be used to predict if turbulence perturbations induced by an upstream gap will influence the turbulence at a given distance downstream.
Near‐infrared Spectra of Lunar Ferrous Mineral Mixtures
Authors: Zhang Xunyu , Cloutis Edward
Published: December 2020

Iron‐bearing minerals are a major component of materials on the lunar surface, and many of them can be distinguished based on the diagnostic absorption features in visible and near‐infrared reflectance spectra. The relationship between the 1 µm absorption (Band I) center and the band area ratio (BAR), defined as the ratio of 2–1 µm absorption areas, provides a sensitive way to estimate the relative abundance of olivine (Ol) and pyroxene. In the plot of the BAR value versus the Band I center, the Ol‐orthopyroxene (Opx) mixing line (derived from terrestrial materials) is strictly applicable only to Ol‐Opx mixtures. Based on published database of laboratory spectra and compositional data for lunar rocks and mineral separates, this study investigated the spectral characteristics of a variety of common Fe2+‐bearing lunar minerals and rocks, such as clinopyroxene (Cpx), ilmenite‐rich basalt, pyroxene‐bearing anorthosite, and glass‐rich impact melt. The lunar Ol‐Cpx‐Opx mixing line for rocks and minerals is determined, which contains less curvature than the Ol‐Opx mixing line, consistent with both the higher Fe2+ content of lunar mafic silicates and the presence of appreciable Cpx. This study suggests that some of the pyroxene‐bearing lunar materials that are rich in ilmenite, glass, or plagioclase can also be distinguished by this method. These results indicate that the plot of the BAR value versus the Band I center is a useful tool for spectral analysis of lunar composition and mineralogy, especially for those having pyroxene‐dominated spectra.
Tidal Effects on the Longitudinal Structures of the Martian Thermosphere and Topside Ionosphere Observed by MAVEN
Authors: Fang Xiaohua , Forbes Jeffrey M. , Gan Quan , Liu Guiping , Thaller Scott , Bougher Stephen , Andersson Laila , Benna Mehdi , Eparvier Francis , Ma Yingjuan , Pawlowski David , England Scott , Jakosky Bruce
Published: December 2020

Longitudinal structures in the Martian thermosphere and topside ionosphere between 150 and 200 km altitudes are studied using in situ electron and neutral measurements from the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Four time intervals are selected for comparison, during which MAVEN sampled similar local time (9.3–10.3 h) and latitude (near 20°S) regions but at different solar longitude positions (two near northern summer solstice, one each at northern vernal and autumnal equinoxes). Persistent and pronounced tidal oscillations characterize the ionosphere and thermosphere, whose longitudinal variations in density are generally in‐phase with each other. Our analysis of simultaneous and collocated neutral and electron data provides direct observational evidence for thermosphere‐ionosphere coupling through atmospheric tides. We conclude that the ionosphere is subject to modulation by upward‐propagating thermal tides, via both tide‐induced vertical displacement and photochemical reactions. Atmospheric tides constitute a ubiquitous and significant perturbation source to the ionospheric electron density, up to ∼15% near 200 km.
P‐wave Tomography and Azimuthal Anisotropy of the Manila‐Taiwan‐Southern Ryukyu Region
Authors: Fan Jianke , Zhao Dapeng
Published: December 2020

Taiwan is considered to be created by interactions between the Manila and Ryukyu subduction zones, which form a normal double‐slab subduction system. Because of the two opposite dipping subductions of the Eurasian Plate (EP) and the Philippine Sea Plate (PSP) around Taiwan, subduction polarity reversal beneath northern Taiwan is presumed, which is accounted for by a slab breakoff model. However, this model has not been convincingly supported by tomographic results so far. Moreover, details of the dynamic process and deformation in this normal double‐slab subduction system are still unclear. In this work, we determine high‐resolution 3‐D tomographic images of isotropic P‐wave velocity and azimuthal anisotropy beneath the Manila‐Taiwan‐southern Ryukyu region, which provide substantial observational constraints on this double‐slab subduction system. Our results clearly show the subducted EP breakoff beneath northern Taiwan. We propose two possible factors causing the slab breakoff: the subducted EP rollback under its own gravity after its subduction cessation and collision with the subducted PSP, which may jointly cause the slab breakoff beneath northern Taiwan after a longer collision history. In addition, the subducted EP rollback may be responsible for magmatism and basalts around Taiwan, as well as recent big earthquakes beneath the Taiwan Strait and the South China Sea (SCS). Our results also reveal anisotropy parallel with the SCS fossil ridge beneath the northernmost Luzon Island. We suggest that the fossil ridge and buoyant plateau subduction and/or the ridge‐parallel mantle flow during the SCS seafloor spreading may result in the ridge‐parallel anisotropy.
TW-SIR: time-window based SIR for COVID-19 forecasts
Authors: Liao Zhifang , Lan Peng , Liao Zhining , Zhang Yan , Liu Shengzong
Published: December 2020

Since the outbreak of COVID-19, many COVID-19 research studies have proposed different models for predicting the trend of COVID-19. Among them, the prediction model based on mathematical epidemiology (SIR) is the most widely used, but most of these models are adapted in special situations based on various assumptions. In this study, a general adapted time-window based SIR prediction model is proposed, which is characterized by introducing a time window mechanism for dynamic data analysis and using machine learning method predicts the basic reproduction number and the exponential growth rate of the epidemic. We analyzed COVID-19 data from February to July 2020 in seven countries–––China, South Korea, Italy, Spain, Brazil, Germany and France, and the numerical results showed that the framework can effectively measure the real-time changes of the parameters during the epidemic, and error rate of predicting the number of COVID-19 infections in a single day is within 5%.
Molecular engineering for high-performance fullerene broadband photodetectors
Authors: Su Mingming , Hu Yajing , Yu Ao , Peng Zhiyao , Long Wangtao , Gao Shixin , Peng Ping , Su Bin , Li Fang-Fang
Published: December 2020

The NiTPP-C60 large-area single-crystal arrays photodetector, which combines the excellent light absorption properties of porphyrin and the good electron transport properties of fullerenes, shows a fast light response and high responsivity.
BOCC: A new modulation based on chirp subcarriers for future BeiDou LEO navigation‐augmented signal
Authors: Zhao Xin , Huang Xinming M. , Sun Guangfu F.
Published: December 2020

For improving the anti‐interference performance and compatibility of a navigation‐augmented signal in future BeiDou Global Navigation Satellite Systems, a new modulation based on chirp subcarriers is proposed, named binary offset chirp carrier modulation, which is formed by multiplying a periodic binary chirp subcarrier with a spreading code signal. And it can make use of the time‐varying frequency for shaping the spectrum and have superior performance in anti‐interference, similar advantage in tracking accuracy, anti‐multipath capability and compatibility compared with binary offset carrier modulations. The binary offset chirp carrier modulations proposed in this paper provide a potential signal design for the future low earth orbit (LEO) navigation‐augmented Global Navigation Satellite Systems.