bluuebunny/crossref_metadata_2025 huggingface dataset:
HPV E2, E4, E5 drive alternative carcinogenic pathways in HPV positive cancers
Authors: Ren Shuling , Gaykalova Daria A. , Guo Theresa , Favorov Alexander V. , Fertig Elana J. , Tamayo Pablo , Callejas-Valera Juan Luis , Allevato Mike , Gilardi Mara , Santos Jessica , Fukusumi Takahito , Sakai Akihiro , Ando Mizuo , Sadat Sayed , Liu Chao , Xu Guorong , Fisch Kathleen M. , Wang Zhiyong , Molinolo Alfredo A. , Gutkind J. Silvio , Ideker Trey , Koch Wayne M. , Califano Joseph A.
Published: August 2020

The dominant paradigm for HPV carcinogenesis includes integration into the host genome followed by expression of E6 and E7 (E6/E7). We explored an alternative carcinogenic pathway characterized by episomal E2, E4, and E5 (E2/E4/E5) expression. Half of HPV positive cervical and pharyngeal cancers comprised a subtype with increase in expression of E2/E4/E5, as well as association with lack of integration into the host genome. Models of the E2/E4/E5 carcinogenesis show p53 dependent enhanced proliferation in vitro, as well as increased susceptibility to induction of cancer in vivo. Whole genomic expression analysis of the E2/E4/E5 pharyngeal cancer subtype is defined by activation of the fibroblast growth factor receptor (FGFR) pathway and this subtype is susceptible to combination FGFR and mTOR inhibition, with implications for targeted therapy.
Methyl-CpG-binding protein 2 drives the Furin/TGF-β1/Smad axis to promote epithelial–mesenchymal transition in pancreatic cancer cells
Authors: Wang Huizhi , Li Jie , He Junbo , Liu Yawen , Feng Wen , Zhou Hailang , Zhou Meng , Wei Hong , Lu Ying , Peng Wanxin , Du Fengyi , Gong Aihua , Xu Min
Published: August 2020

Methyl-CpG-binding protein 2 (MeCP2) has been characterized as an oncogene in several types of cancer. However, its precise role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. Hence, this study aimed to evaluate the potential role of MeCP2 in pancreatic cancer progression. We found that MeCP2 was upregulated in pancreatic cancer tissues, enhanced migration, invasion, and proliferation in pancreatic cancer cells, and promoted tumorigenesis. Further evidence revealed that MeCP2 remarkably increased the mesenchymal markers vimentin, N-cadherin, and Snail, and downregulated the expression of the epithelial markers E-cadherin and ZO-1, indicating that MeCP2 promotes epithelial–mesenchymal transition (EMT). In addition, we found that MeCP2 upregulated the expression of Furin, activated TGF-β1, and increased the levels of p-Smad2/3. Importantly, we demonstrated that MeCP2, as a coactivator, enhanced Smad3 binding to the furin promoter to improve its transcription. Therefore, MeCP2/Smads drive the expression of Furin to activate TGF-β1, and in turn, phosphorylate Smad2/3, which forms a positive-feedback axis to promote EMT in pancreatic cancer cells.
Brain-derived neurotrophic factor polymorphism Val66Met protects against cancer-related fatigue
Authors: Feng Li Rebekah , Juneau Paul , Regan Jeniece M. , Liwang Josephine , Alshawi Sarah , Wang Angela , Saligan Leorey N.
Published: August 2020

Cancer-related fatigue is an extremely common and debilitating psychiatric symptom that affects up to 80% of cancer patients. Despite its negative impact on the patient’s quality of life, there is no well-established biomarker or mechanisms associated with this debilitating condition. The functional brain-derived neurotrophic factor (BDNF) Val66Met single nucleotide polymorphism (SNP) has been associated with a variety of psychiatric illnesses. We hypothesized that Val66Met may influence the risk for developing cancer-related fatigue. BDNF Val66Met was analyzed by polymerase chain reaction in 180 patients with confirmed cancer diagnoses. Fatigue was measured using the Functional Assessment of Cancer Therapy-Fatigue (FACIT-Fatigue) questionnaire. Depression was measured using the Hamilton Depression Scale (HAM-D). Data were transformed when necessary and regression models were constructed to access the association between genotype and symptom severity. Participants carrying the Met allele reported significantly less fatigue compared to the Val/Val genotype group. The presence of the Met allele did not influence depression levels. The results suggest that the BDNF Val66Met polymorphism confers protective advantage against cancer-related fatigue; whereas having the Val/Val genotype may be a genetic risk factor. Findings from this study not only provide clues to the neural basis of cancer-related fatigue, but also allow for symptom severity prediction and patient education with the goal to improve symptom management.
Environmental prospecting of black yeast-like agents of human disease using culture-independent methodology
Authors: Costa Flávia de Fátima , da Silva Nickolas Menezes , Voidaleski Morgana Ferreira , Weiss Vinicius Almir , Moreno Leandro Ferreira , Schneider Gabriela Xavier , Najafzadeh Mohammad J. , Sun Jiufeng , Gomes Renata Rodrigues , Raittz Roberto Tadeu , Castro Mauro Antonio Alves , de Muniz Graciela Bolzón Inez , de Hoog G. Sybren , Vicente Vania Aparecida
Published: August 2020

Melanized fungi and black yeasts in the family Herpotrichiellaceae (order Chaetothyriales) are important agents of human and animal infectious diseases such as chromoblastomycosis and phaeohyphomycosis. The oligotrophic nature of these fungi enables them to survive in adverse environments where common saprobes are absent. Due to their slow growth, they lose competition with common saprobes, and therefore isolation studies yielded low frequencies of clinically relevant species in environmental habitats from which humans are thought to be infected. This problem can be solved with metagenomic techniques which allow recognition of microorganisms independent from culture. The present study aimed to identify species of the family Herpotrichiellaceae that are known to occur in Brazil by the use of molecular markers to screen public environmental metagenomic datasets from Brazil available in the Sequence Read Archive (SRA). Species characterization was performed with the BLAST comparison of previously described barcodes and padlock probe sequences. A total of 18,329 sequences was collected comprising the genera Cladophialophora, Exophiala, Fonsecaea, Rhinocladiella and Veronaea, with a focus on species related to the chromoblastomycosis. The data obtained in this study demonstrated presence of these opportunists in the investigated datasets. The used techniques contribute to our understanding of environmental occurrence and epidemiology of black fungi.
The effects of intravenous iron supplementation on fatigue and general health in non-anemic blood donors with iron deficiency: a randomized placebo-controlled superiority trial
Authors: Keller Peter , von Känel Roland , Hincapié Cesar A. , da Costa Bruno R. , Jüni Peter , Erlanger Tobias E. , Andina Nicola , Niederhauser Christoph , Lämmle Bernhard , Fontana Stefano
Published: August 2020

We investigated whether intravenous iron supplementation improves fatigue and general health in non-anemic repeat adult blood donors with iron deficiency (ferritin ≤ 50 µg/L). Of 1,487 potentially eligible participants, 203 were randomly assigned to a single intravenous dose of 800 mg iron-carboxymaltose and 202 to placebo; 393 participants completed the trial. At 6 to 8 weeks after intervention, self-rated mean fatigue scores (numeric rating scale from 1–10, primary outcome) were 3.9 ± 1.8 in the iron supplementation group and 4.0 ± 2.2 in the placebo group, showing no group difference (p = 0.819). Pre-specified subgroup analyses of gender, ferritin < 25 µg/L and fatigue ≥ 4 points, as well as exploratory analyses of lower ferritin cut-offs did not reveal any between-group differences. In terms of secondary outcomes, the mean differences were 114.2 µg/L for ferritin (95% CI 103.1–125.3) and 5.7 g/L for hemoglobin (95% CI 4.3–7.2) with significantly higher values in the iron supplementation group. No group differences were observed for different measures of general well-being and other clinical and safety outcomes. Intravenous iron supplementation compared with placebo resulted in increase of ferritin and hemoglobin levels in repeat blood donors with low iron stores, yet had no effect on fatigue and general well-being.
Maternal lipid levels across pregnancy impact the umbilical cord blood lipidome and infant birth weight
Authors: LaBarre Jennifer L. , Puttabyatappa Muraly , Song Peter X. K. , Goodrich Jaclyn M. , Zhou Ling , Rajendiran Thekkelnaycke M. , Soni Tanu , Domino Steven E. , Treadwell Marjorie C. , Dolinoy Dana C. , Padmanabhan Vasantha , Burant Charles F.
Published: August 2020

Major alterations in metabolism occur during pregnancy enabling the mother to provide adequate nutrients to support infant development, affecting birth weight (BW) and potentially long-term risk of obesity and cardiometabolic disease. We classified dynamic changes in the maternal lipidome during pregnancy and identified lipids associated with Fenton BW z-score and the umbilical cord blood (CB) lipidome. Lipidomics was performed on first trimester maternal plasma (M1), delivery maternal plasma (M3), and CB plasma in 106 mother-infant dyads. Shifts in the maternal and CB lipidome were consistent with the selective transport of long-chain polyunsaturated fatty acids (PUFA) as well as lysophosphatidylcholine (LysoPC) and lysophosphatidylethanolamine (LysoPE) species into CB. Partial correlation networks demonstrated fluctuations in correlations between lipid groups at M1, M3, and CB, signifying differences in lipid metabolism. Using linear models, LysoPC and LysoPE groups in CB were positively associated with BW. M1 PUFA containing triglycerides (TG) and phospholipids were correlated with CB LysoPC and LysoPE species and total CB polyunsaturated TGs. These results indicate that early gestational maternal lipid levels influence the CB lipidome and its relationship with BW, suggesting an opportunity to modulate maternal diet and improve long-term offspring cardiometabolic health.
Genotoxicity and mutagenicity research in Quilombola communities
Authors: de Moraes Filho Aroldo Vieira , Manso João Antonio Xavier , Martins Wanderléia Eleutério , Marinho Núbia Aguiar , de Oliveira Santos Mônica , Perim Neto José , Duarte Sabrina Sara Moreira , da Cruz Aparecido Divino , da Silva Cláudio Carlos , Barbosa Mônica Santiago , de Jesus Pires Débora , Carneiro Lílian Carla
Published: August 2020

The Quilombola communities are mostly isolated and deprived of sources of treated water, garbage collection and sewage, consuming fresh water from wells, streams, lakes, among others. This lack of basic infrastructure can be a relevant factor in exposing residents to substances and factors that are harmful to the integrity of their genetic material that can lead to carcinogenesis. Based on this, the objective of this study was to evaluate the genomic and mutagenic/cytotoxic damage in the adult population of two Quilombola communities (one urban and another rural region), in the state of Goiás, Brazil. For this purpose, the leukocyte of peripheral blood Comet Assay in 68 individuals and Micronucleus Test from exfoliated buccal cells of oral mucosa in 21 volunteers were performed. The results evidenced genomic damage, especially for the community of Aparecida de Goiânia city, which detected significant values (p < 0.05), for the length of the comet’s tail and for of the Olive Tail Moment. In the micronucleus test, significant differences were only detected (p < 0.05), when it came to the distribution of nuclear changes among the groups. Therefore, it is essential to perform constant population biomonitoring studies to help guarantee health and, consequently, the quality of life.
Electrogenerated chemiluminescence resonance energy transfer between ZnGa2O4/g-C3N4 and gold nanoparticles/graphene and its application in the detection of thrombin
Authors: Liu Hui , Yin Hao , Yang TingTing , Ding HouCheng , Dong YongPing
Published: August 2020

A label-free ECL sensor for thrombin was fabricated based on ECL resonance energy transfer occurred between ZnGa2O4/g-C3N4 and AuNP/GR nanocomposites, which revealed a new role of spinel-type semiconductor oxides in the fabrication of ECL sensors.
Base-free oxidation of alcohols enabled by nickel(ii)-catalyzed transfer dehydrogenation
Authors: Ye Danfeng , Liu Zhiyuan , Sessler Jonathan L. , Lei Chuanhu
Published: August 2020

The oxidation of alcohols was successfully realized via nickel(ii)-catalyzed transfer dehydrogenation under base-free conditions.
Visualising brain capillaries in magnetic resonance images via supramolecular self-assembly
Authors: Mahara Atsushi , Saito Shigeyoshi , Yamaoka Tetsuji
Published: August 2020

We report a supramolecular self-assembly of one fluorescein and three Gd–chelate conjugated 8-arm polyethylene glycols for visualizing brain capillaries in magnetic resonance imaging.
Heterometal incorporation in NH2-MIL-125(Ti) and its participation in the photoinduced charge-separated excited state
Authors: Hanna Lauren , Long Conor L. , Zhang Xiaoyi , Lockard Jenny V.
Published: August 2020

X-ray spectroscopy studies reveal the location and role of Fe3+ sites incorporated in a Ti-based MOF exhibiting photo-induced charge separation.
Dual-mode excitation β-NaGdF4:Yb/Er@β-NaGdF4:Yb/Nd core–shell nanoparticles with NIR-II emission and 5 nm cores: controlled synthesis via NaF/RE regulation and the growth mechanism
Authors: Cheng Chunyan , Xu Yueshan , De Gejihu , Wang Jianxun , Wu Wei , Tian Yuexing , Wang Shasha
Published: August 2020

Dual-mode excitation β-NaGdF4:Yb/Er@β-NaGdF4:Yb/Nd core–shell nanoparticles with NIR-II emission and 5 nm cores were synthesized using an ultra-low single dose of NaF.
Farmed Jumbo shrimp molts: an ionic liquid strategy to increase chitin yield per animal while controlling molecular weight
Authors: Wineinger Hannah B. , Kelly Adrian , Shamshina Julia L. , Rogers Robin D.
Published: August 2020

A chitin extraction strategy of collecting all shrimp molts during their lifetime leads to not only a very large increase in overall resource abundance, but also control over the molecular weight of the resulting chitin.
Catalyst- and oxidant-free electrochemical para-selective hydroxylation of N-arylamides in batch and continuous-flow
Authors: Liu Cheng-Kou , Chen Meng-Yi , Lin Xin-Xin , Fang Zheng , Guo Kai
Published: August 2020

A catalyst-, oxidant-, acidic solvent- and quaternary ammonium salt-free electrochemical para-selective hydroxylation of N-arylamides at rt in batch and continuous-flow was developed.
Assessment of the performance of quantitative feature-based transfer learning LIBS analysis of chromium in high temperature alloy steel samples
Authors: Chang Fu , Lu Huili , Sun Hao , Yang Jianhong
Published: August 2020

The spectral data of calibration samples at room temperature and the spectral data of uncalibrated samples at high temperature are together transferred into a Hilbert space where an LIBS regression model is established.
Tuning the binding behaviors of a protein YAP65WW domain on graphenic nano-sheets with boron or nitrogen atom doping
Authors: Jia Xiao , Yang Yanmei , Liu Yang , Niu Weihua , Li Yong-Qiang , Zhao Mingwen , Mu Yuguang , Li Weifeng
Published: August 2020

Molecular dynamics simulations predict that atom doping is an efficient way to regulate the binding strength and structural changes of protein with nanomaterials, which makes it a prospective solution for design and fabrication of advanced nanomaterials with desired function.
Size-dependent electrocatalytic activity of ORR/OER on palladium nanoclusters anchored on defective MoS2monolayers
Authors: He Fan , Liu Yuejie , Cai Qinghai , Zhao Jingxiang
Published: August 2020

The catalytic performance of MoS2monolayer for oxygen reduction/evolution can be effectively tuned by carefully controlling the sizes of the deposited Pd clusters.
Fluorescence regional integration combined with parallel factor analysis to quantify fluorescencent spectra for dissolved organic matter released from manure biochars
Authors: Peng Na , Wang Kaifeng , Tu Ningyu , Liu Yang , Li Zhuanling
Published: August 2020

Dissolved Organic Matter (DOM) in biochars is important to carbon dynamics and contaminant transport in soils
Challenges and opportunities of hydrothermal carbonisation in the UK; case study in Chirnside
Authors: Bevan Eloise , Fu Jile , Zheng Ying
Published: August 2020

Hydrothermal carbonization: a great technology converting biomass waste to energy.
Development of a new bisphenol A electrochemical sensor based on a cadmium(ii) porphyrin modified carbon paste electrode
Authors: Jemmeli Dhouha , Mchiri Chadlia , Dridi Chérif , Nasri Habib , Dempsey Eithne
Published: August 2020

In this study, the (5,10,15,20-tetrakis[(4-methoxyphenyl)]porphyrinato)cadmium(ii) complex ([Cd(TMPP)]) was successfully used as a modifier in a carbon paste electrode (CPE) and exploited for bisphenol A (BPA) detection.
Effect of lemon peel flavonoids on UVB-induced skin damage in mice
Authors: Wang Jun , Bian Yunfeng , Cheng Yujiao , Sun Rongrong , Li Guijie
Published: August 2020

By establishing an effective ultraviolet B (UVB) radiation model of skin damage in mice, the effect of lemon peel flavonoids (LPF) on skin damage was explored.
Environmental valorisation of bagasse fly ash: a review
Authors: Patel Himanshu
Published: August 2020

Worldwide, each year the sugar industry generates bagasse fly ash (BFA) in the process of producing sugar including ethanol and jaggery.
Recently synthesized (Ti1−xMox)2AlC (0 ≤ x ≤ 0.20) solid solutions: deciphering the structural, electronic, mechanical and thermodynamic properties via ab initio simulations
Authors: Ali M. A. , Naqib S. H.
Published: August 2020

The structural, electronic, mechanical and thermodynamic properties of (Ti1−xMox)2AlC (0 ≤ x ≤ 0.20) were explored using density functional theory.
Peer‐to‐peer local electricity market platform pricing strategies for prosumers
Authors: Teotia Falti , Mathuria Parul , Bhakar Rohit
Published: August 2020

Peer‐to‐peer (P2P) energy trading in the local electricity market (LEM) handles local energy trades among prosumers connected to the same distribution network. LEM is governed by prosumer's individual choices, self‐management and neighbourhood interactions. This study investigates the design of P2P LEM platform based on sharing economy for non‐professional prosumers and provides an exposition towards conceptual integration of LEM in the existing market. Design features of the P2P platform are based on two‐sided matching market theory. Here, P2P platform provider, i.e. an aggregator, operates a two‐sided market platform to match and set prices for prosumers having different willingness to buy/sell. The economic rationale of the P2P platform is highlighted by a variety of pricing strategies that the aggregator could offer, focusing on the benefits of aggregator and prosumers. As the total number of trades among peers is a crucial factor to determine aggregator profitability, pricing with a capability to induce prosumer surplus acts as an instrument for the aggregator to bind prosumers in P2P LEM.
On dimensional transmutation in 1 + 1D quantum hydrodynamics
Authors: Gorsky Alexander , Koroteev Peter , Koroteeva Olesya , Vainshtein Arkady
Published: August 2020

Recently, a detailed correspondence was established between, on one side, four- and five-dimensional large-N supersymmetric gauge theories with N = 2 supersymmetry and adjoint matter and, on the other side, integrable 1 + 1-dimensional quantum hydrodynamics. Under this correspondence, the phenomenon of dimensional transmutation, familiar in asymptotically free quantum field theories, gets mapped to the transition from the elliptic Calogero–Moser many-body system to the closed Toda chain. In this paper, we attempt to formulate the hydrodynamical counterpart of the dimensional transmutation phenomenon inspired by the identification of the periodic intermediate long wave equation as the hydrodynamical limit of the elliptic Calogero–Moser/Ruijsenaars–Schneider system. We also conjecture that the chiral flow in the vortex fluid provides the proper framework for the microscopic description of such dimensional transmutation in 1 + 1D hydrodynamics. We provide a geometric description of this phenomenon in terms of the Atiyah Drinfeld Hitchin Manin moduli space.
Radiative energy transfer assisted amplified spontaneous emission in asymmetric-coupled-waveguide structures
Authors: Soniya N. , Aswathy S. , Anagha G. S. , Shadak Alee K.
Published: August 2020

We demonstrate the efficient amplified spontaneous emission (ASE) of rhodamine 640 in asymmetric-coupled-waveguides. In these structures, two active waveguides, one doped with [2-[2-[4-(dimethylamino)phenyl]ethenyl]-6-methyl-4H-pyran-4-ylidene]-propanedinitrile (DCM) and the other with rhodamine 640, are coupled by a passive layer of polyvinyl alcohol. Under a suitable pumping wavelength of 500 nm, the DCM waveguiding layer acts as the donor and rhodamine waveguiding layer acts as the acceptor. Time-resolved fluorescence measurements are employed to confirm that radiative energy transfer is the responsible mechanism for ASE when the waveguiding layers are separated by a thickness of less than 50 nm. In this case, the ASE threshold was found to be reduced by a factor of 16, associated with an intensity enhancement of 56 times, compared to that of the rhodamine waveguiding layer. Next, we investigate the ASE properties of asymmetric-coupled-waveguides as a function of coupling layer thickness. The thickness-dependent coupling constant is simulated using the coupled-mode theory, and its behavior is applied to understand the experimental results.
Light induced electron spin resonance properties of van der Waals CrX3 (X = Cl, I) crystals
Authors: Singamaneni S. R. , Martinez L. M. , Niklas J. , Poluektov O. G. , Yadav R. , Pizzochero M. , Yazyev O. V. , McGuire M. A.
Published: August 2020

The research on layered van der Waals (vdW) magnets is rapidly progressing owing to exciting fundamental science and potential applications. In bulk crystal form, CrCl3 is a vdW antiferromagnet with in-plane ferromagnetic ordering below 17 K, and CrI3 is a vdW ferromagnet below 61 K. Here, we report on the electron spin resonance (ESR) properties of CrCl3 and CrI3 single crystals upon photo-excitation in the visible range. We noticed remarkable changes in the ESR spectra upon illumination. In the case of CrCl3, at 10 K, the ESR signal is shifted from g = 1.492 (dark) to 1.661 (light), the linewidth increased from 376 to 506 Oe, and the signal intensity is reduced by 1.5 times. Most interestingly, the observed change in the signal intensity is reversible when the light is cycled on/off. We observed almost no change in the ESR spectral parameters in the paramagnetic phase (>20 K) upon illumination. Upon photo-excitation of CrI3, the ESR signal intensity is reduced by 1.9 times; the g-value increased from 1.956 to 1.990; the linewidth increased from 1170 to 1260 Oe at 60 K. These findings are discussed by taking into account the skin depth, the slow relaxation mechanism, and the appearance of low-symmetry fields at the photo-generated Cr2+ Jahn–Teller centers. Such an increase in the g-value as a result of photo-generated Cr2+ ions is further supported by our many-body wavefunction calculations. This work has the potential to extend to monolayer vdWs magnets by combining ESR spectroscopy with optical excitation and detection.
A potential for molecular simulation of compounds with linear moieties
Authors: van der Spoel David , Henschel Henning , van Maaren Paul J. , Ghahremanpour Mohammad M. , Costa Luciano T.
Published: August 2020

The harmonic angle bending potential is used in many force fields for (bio)molecular simulation. The force associated with this potential is discontinuous at angles close to 180°, which can lead to numeric instabilities. Angle bending of linear groups, such as alkynes or nitriles, or linear molecules, such as carbon dioxide, can be treated by a simple harmonic potential if we describe the fluctuations as a deviation from a reference position of the central atom, the position of which is determined by the flanking atoms. The force constant for the linear angle potential can be derived analytically from the corresponding force constant in the traditional potential. The new potential is tested on the properties of alkynes, nitriles, and carbon dioxide. We find that the angles of the linear groups remain about 2° closer to 180° using the new potential. The bond and angle force constants for carbon dioxide were tuned to reproduce the experimentally determined frequencies. An interesting finding was that simulations of liquid carbon dioxide under pressure with the new flexible model were stable only when explicitly modeling the long-range Lennard-Jones (LJ) interactions due to the very long-range nature of the LJ interactions (>1.7 nm). In the other tested liquids, we find that a Lennard-Jones cutoff of 1.1 nm yields similar results as the particle mesh Ewald algorithm for LJ interactions. Algorithmic factors influencing the stability of liquid simulations are discussed as well. Finally, we demonstrate that the linear angle potential can be used in free energy perturbation calculations.
Screening within accumulation layers of molecular semiconductors
Authors: Sailer D. , Bornschlegl A. , Kersting R.
Published: August 2020

In organic field-effect transistors, conductivity is achieved by electronically injected charges that form high-density accumulation layers. We report self-consistent calculations of Poisson's equation, carrier statistics, and the Drude permittivity of the carrier gas at the interface between semiconductors and insulators. The results show that the injected carriers efficiently screen local potentials. Additionally, the AC permittivity of the carriers reduces electrical fields particularly at frequencies of several THz. This dynamic screening may affect the formation of large polarons and the transient localization of carriers.
Preparation uncertainty implies measurement uncertainty in a class of generalized probabilistic theories
Authors: Takakura Ryo , Miyadera Takayuki
Published: August 2020

In quantum theory, it is known for a pair of noncommutative observables that there is no state on which they take simultaneously definite values and that there is no joint measurement of them. They are called preparation uncertainty and measurement uncertainty, respectively, and research has unveiled that they are not independent from but related with each other in a quantitative way. This study aims to reveal whether similar relations to quantum ones hold also in generalized probabilistic theories (GPTs). In particular, a certain class of GPTs is considered, which can be characterized by transitivity and self-duality and regarded as extensions of quantum theory. It is proved that there are close connections expressed quantitatively between two types of uncertainty on a pair observables also in those theories: if preparation uncertainty exists, then measurement uncertainty also exists, and they are described by similar inequalities. Our results manifest that their correspondences are not specific to quantum theory but more universal ones.
A novel Ka-band chirped-pulse spectrometer used in the determination of pressure broadening coefficients of astrochemical molecules
Authors: Hearne Thomas S. , Abdelkader Khedaoui Omar , Hays Brian M. , Guillaume Théo , Sims Ian R.
Published: August 2020

A novel chirped-pulse Fourier transform microwave (CP-FTMW) spectrometer has been constructed to cover the Ka-band (26.5 GHz–40 GHz) for use in the CRESUCHIRP project, which aims to study the branching ratios of reactions at low temperatures using the chirped-pulse in uniform flow technique. The design takes advantage of recent developments in radio-frequency components, notably, high-frequency, high-power solid-state amplifiers. The spectrometer had a flatness of 5.5 dB across the spectral range, produced harmonic signals below −20 dBc, and the recorded signal scaled well to 6 × 106 averages. The new spectrometer was used to determine pressure broadening coefficients with a helium collider at room temperature for three molecules relevant to astrochemistry, applying the Voigt function to fit the magnitude of the Fourier-transformed data in the frequency domain. The pressure broadening coefficient for carbonyl sulfide was determined to be (2.45 ± 0.02) MHz mbar-1 at room temperature, which agreed well with previous measurements. Pressure broadening coefficients were also determined for multiple transitions of vinyl cyanide and benzonitrile. Additionally, the spectrometer was coupled with a cold, uniform flow from a Laval nozzle. The spectrum of vinyl cyanide was recorded in the flow, and its rotational temperature was determined to be (24 ± 11) K. This temperature agreed with a prediction of the composite temperature of the system through simulations of the experimental environment coupled with calculations of the solution to the optical Bloch equations. These results pave the way for future quantitative studies in low-temperature and high-pressure environments using CP-FTMW spectroscopy.
Applying Marcus theory to describe the carrier transports in organic semiconductors: Limitations and beyond
Authors: Shuai Zhigang , Li Weitang , Ren Jiajun , Jiang Yuqian , Geng Hua
Published: August 2020

Marcus theory has been successfully applied to molecular design for organic semiconductors with the aid of quantum chemistry calculations for the molecular parameters: the intermolecular electronic coupling V and the intramolecular charge reorganization energy λ. The assumption behind this is the localized nature of the electronic state for representing the charge carriers, being holes or electrons. As far as the quantitative description of carrier mobility is concerned, the direct application of Marcus semiclassical theory usually led to underestimation of the experimental data. A number of effects going beyond such a semiclassical description will be introduced here, including the quantum nuclear effect, dynamic disorder, and delocalization effects. The recently developed quantum dynamics simulation at the time-dependent density matrix renormalization group theory is briefly discussed. The latter was shown to be a quickly emerging efficient quantum dynamics method for the complex system.
Unitary coupled cluster ground- and excited-state molecular properties
Authors: Hodecker Manuel , Dreuw Andreas
Published: August 2020

A scheme for the calculation of molecular properties within the framework of unitary coupled-cluster (UCC) theory in both the electronic ground and excited states is presented. The scheme is based on an expectation-value ansatz, similar to the equation-of-motion coupled-cluster method or the intermediate state representation (ISR) approach of the algebraic–diagrammatic construction (ADC) scheme. Due to the UCC ansatz, the resulting equations cannot be given by closed-form expressions but need to be approximated. Explicit expressions for the expectation value of a general one-particle operator correct through second order in perturbation theory have been derived and coded for the electronic ground state as well as for excited states of predominant single-excitation character. The resulting equations are shown to be equivalent to those of the second-order ADC/ISR procedure. As first computational tests, the second-order UCC method (UCC2) and the one employing third-order amplitudes (also eigenvectors) together with the second-order density matrix, denoted as UCC3(2), are applied to the calculation of dipole moments for a series of small closed- and open-shell systems as well as 4-cyanoindole and 2,3-benzofuran and compared to full configuration interaction or experimental results. For the aromatic organic molecules, the UCC2 method is shown to be sufficient for the ground-state dipole moment, whereas the UCC3(2) scheme is superior for excited-state dipole moments.
Empowering 2D nanoelectronics via ferroelectricity
Authors: Ryu Hojoon , Xu Kai , Li Dawei , Hong Xia , Zhu Wenjuan
Published: August 2020

Introducing ferroelectricity to two-dimensional van der Waals (vdW) materials such as graphene, transition metal dichalcogenides, and black phosphorous presents a promising route for developing high-speed and low-power nanoelectronics. This Perspective reviews two actively pursued materials strategies, ferroelectric/vdW heterostructures and vdW ferroelectric materials. The topics discussed include their application potential and performance limitations as memory, logic, sensing, and optical devices, as well as the challenges and outlook of the field.
Generation of a quasi-static magnetic field by a circularly polarised laser pulse due to tunnelling gas ionisation
Authors: Gabdrakhmanov I.M. , Bychenkov V.Yu.
Published: August 2020

We present a theoretical model of the quasi-static magnetic field generation in a laser channel, which is formed behind the front of a short laser pulse that ionises a gas. The generation of a magnetic field is caused by the appearance of the electron pressure anisotropy during tunnelling ionisation of atoms. In the considered case of subrelativistic laser light intensities, the generated magnetic field can reach ∼1 MG with an energy transformation ratio of about 1 %, which paves the way for identifying the proposed mechanism when use is made of a wide class of ultrashort pulse lasers.
Line curvature algorithm in laser ektacytometry of red blood cells
Authors: Nikitin S.Yu. , Ustinov V.D. , Shishkin S.D. , Lebedeva M.S.
Published: August 2020

The iso-intensity line curvature algorithm in laser ektacytometry of red blood cells is investigated by numerical simulation. The algorithm is designed to measure the average deformability, as well as the width and asymmetry of the red blood cell deformability distribution in a blood sample under study. The accuracy and scope of the algorithm are determined. Using a bimodal ensemble as an example, the possibility of determining the fraction of weakly deformable red blood cells in a blood sample by laser ektacytometry is demonstrated.
Effect of the magnetic field on the size of nanoparticles obtained by ablation of a cobalt – copper target in a liquid
Authors: Tveryanovich Yu.S. , Abdrashitov G.O. , Menchikov L.G.
Published: August 2020

Co – Cu nanoparticles were obtained by pulsed laser ablation in a liquid medium in a constant magnetic field. The organic solvent, hexane, served as a liquid medium. The influence of the magnetic field on the formation of nanoparticles was studied. It is shown that the magnetic field leads to a decrease in the size distribution width of the resulting nanoparticles.
Numerical simulation of the divergence and optical confinement factor of a semiconductor laser with an asymmetric periodic multilayer AlGaInAs/InP waveguide
Authors: Kurnosov V.D. , Kurnosov K.V.
Published: August 2020

The divergence and optical confinement factor of a semiconductor laser with an asymmetric periodic (multilayer) waveguide are numerically simulated. The reasons for the choice of the given heterostructure design are explained, and the consequences of choosing other layer structures are considered. It is shown how to choose the active waveguide thickness, the active region position on the waveguide, and the multilayer waveguide grating period.
Decreasing the amplitude of macroscopic quantum fluctuations in the case of transient SRS
Authors: Didenko N.V. , Konyashchenko A.V. , Losev L.L.
Published: August 2020

It is shown experimentally that, under the conditions of transient stimulated Raman scattering, pumping by two successive orthogonally polarised laser pulses makes it possible to reduce the amplitude of macroscopic quantum energy fluctuations of a Stokes pulse by a factor of 4 in comparison with single-shot pumping. An energy dispersion of 0.9 % for the first Stokes component is obtained in hydrogen at a relative energy dispersion of ytterbium laser pulses of 0.4 %.
Synthesis of TiO2 nanoparticles decorated with gold nanoclusters using pulsed laser ablation in liquid
Authors: Gurbatov S.O. , Mintcheva N. , Iwamori S. , Kulinich S.A. , Kuchmizhak A.A.
Published: August 2020

Amorphous spherical titanium dioxide (TiO2) nanoparticles, decorated gold nanoparticles, are shown to be formed under irradiation of commercial TiO2 nanopowders dispersed in aqueous solution of hydrogen tetrachloroaurate (HAuCl4) by second-harmonic nanosecond pulses of an Nd : YAG laser. It is found that these hybrid nanostructures are formed during laser-induced remelting of the initial nanoparticles, stimulated by gold nanoclusters (providing more efficient absorption of visible laser radiation by titanium dioxide) recovered on their surface. The morphology and chemical composition of the newly formed hybrid nanomaterials are investigated in detail by electron microscopy, Raman spectroscopy, and energy-dispersive analysis. It is shown that the average size and number of gold nanoparticles recovered on the TiO2 surface can be controlled by varying the concentration ratio of the initial nanomaterial and HAuCl4. A spectroscopic analysis of light scattering by single hybrid nanoparticles and the results of numerical calculation of the structure of electromagnetic fields near their surface indicate good prospects of these hybrid nanomaterials for various applications in modern optics, optoelectronics, and nanophotonics; for example, for designing chemo- and biosensor platforms and new-generation solar cells.
No support for purported effects of salt-tolerant stream invertebrates on the salinity responses of salt-sensitive stream invertebrates
Authors: Chessman Bruce C.
Published: August 2020

Increases in salinity can severely affect freshwater ecosystems, and research on the salt tolerances of freshwater species, and factors that modify tolerance, can improve our understanding and prediction of the effects of salinity. In order to test the hypothesis that salt-tolerant freshwater invertebrates can alter the salinity responses of salt-sensitive freshwater invertebrates, publicly available data from a recent study of artificial mesocosms that claimed to confirm this hypothesis were analysed in the present study. No supporting evidence was found for the hypothesis, with apparent salinity responses of salt-sensitive invertebrates varying no more with greater or lesser exposure to salt-tolerant invertebrates than expected merely by chance. The original findings were apparently misguided through unrecognised confounding of the experimental design, inadequate statistical hypothesis testing and accepting ostensible effects without considering their biological and ecological plausibility.
Intrinsically disordered linkers control tethered kinases via effective concentration
Authors: Dyla Mateusz , Kjaergaard Magnus
Published: August 2020

Significance

Kinases are often tethered to their substrates, and many phosphorylation reactions thus occur inside macromolecular complexes. However, it is currently not known how such tethering affects the rate of phosphorylation. We show that tethering can enhance the rate by orders of magnitude but that the enhancement is highly sensitive to the length of the linker. We provide an equation describing tethered reactions and show that their rates can only partially be predicted from untethered reactions. We suggest a mechanism for how changes in linkers and scaffolding proteins may alter the output of signaling pathways.
Energy flow and production ecology.
Authors: Rees Paul A.
Published: August 2020

This chapter contains questions about the acquisition of energy by ecosystems, its fate within them, and the influence this has on ecosystem structure and functioning.
‘The Boat is full!’: predictors of perceived migrant group size and perceived right to stay for immigrants (‘¡El barco está lleno!’: predictores del tamaño percibido de los grupos migrantes y de su derecho a residir en el país)
Authors: Zagefka Hanna , Moftizadeh Nali , Barber Jessica , Lay Siugmin , Barn Ravinder
Published: August 2020

Predictors of perceived population size and perceived right to reside in the UK were tested for immigrants to Britain. Two studies explored psychological responses of British respondents to immigration to the UK. A questionnaire study examined responses towards migrants living in the UK from India, Poland and Syria (Study 1, N = 136). In this study, perceived intergroup similarity and intergroup threat predicted intergroup affect, which in turn predicted estimates of the migrant group size and the perceived right of the migrants to reside in the UK. Study 2 ( N = 126) was an experiment which manipulated similarity and threat, and elicited responses towards a fictional migrant group, to get a better handle on the causal direction of effects observed in Study 1. Taken together, the studies showed that perceived population size and perceived right to reside in Britain were predicted by intergroup similarity, threat and affect.
Computational treatment of electron and photon collisions with atoms, ions, and molecules: the legacy of Philip G Burke
Authors: Bartschat Klaus , Brown Andrew , van der Hart Hugo W. , Colgan James , Scott NS , Tennyson Jonathan
Published: August 2020

This review summarizes the path-breaking contributions of Philip George Burke (1932–2019) to atomic, molecular, and optical physics, in particular the computational treatment of electron and photon collisions with atoms, ions, and molecules.
The role of anchoring groups in ruthenium(II)-bipyridine sensitized p-type semiconductor solar cells—a quantum chemical approach
Authors: Sen Anik , Kupfer Stephan , Gräfe Stefanie , Groβ Axel
Published: August 2020

Ru(II)-bipyridine complexes connected with p-type semiconductors (p-SCs) are promising systems for photocatalytic applications such as in dye-sensitised solar cells. The photosensitizer-semiconductor interface—governed by the anchoring group—is of vital importance for the electronic properties of the systems as it determines the long-term stability to the semiconductor surface through its binding ability and also affects the hole injection from the dye to the semiconductor. In this contribution, the role of the anchoring groups in ruthenium(II)-bipyridine sensitized p-type semiconductor solar cells has been addressed by quantum chemical calculations based on density functional theory (DFT) and time-dependent DFT. Both, the interaction of a series of anchoring groups with a NiO surface, as well as several thermodynamical parameter governing the efficiency of a Ru(II)-bipyridine dye coupled to these anchoring groups have been determined and analysed. Based on these calculations, new anchors for p-SC with improved properties are proposed. In addition, the influence of aliphatic spacers and the presence of solvents on the properties of the anchored Ru(II)-bipyridine complexes are thoroughly addressed.
Role of hole trapping by deep acceptors in electron-beam-induced current measurements in β-Ga2O3 vertical rectifiers
Authors: Yakimov E B , Polyakov A Y , Smirnov N B , Shchemerov I V , Vergeles P S , Yakimov E E , Chernykh A V , Xian Minghan , Ren F , Pearton S J
Published: August 2020

Current increases in vertical-geometry Ga2O3 rectifiers during electron-beam-induced current measurements are dominated by the impact ionization of deep acceptors in the depletion region. At room temperature, mobile hole diffusion in the quasi-neutral region of Schottky diodes contributes significantly to the charge collection efficiency. Even when electron–hole pairs are created well inside the space charge region, there are significant losses of charge collection efficiency due to the trapping of holes by deep acceptors in the lower half of the bandgap. Capacitance–voltage profiling under illumination points to deep acceptors with optical ionization close to 2.3 eV as the most important agents of capture. Collection efficiency can be improved by increasing the electric field in the space charge region. The jump in collection efficiency at electric fields close to (5–6) × 105 V cm−1 is attributed to the impact ionization of these deep acceptors. These processes can manifest themselves in measurements of the impact ionization coefficients and breakdown voltages of β-Ga2O3 rectifiers and in analyses of the response times of β-Ga2O3 photodetectors.
Structural, magnetic and dielectric properties in 3d–5d based Sr2FeIrO6 thin films
Authors: Kharkwal K C , Patel Roshan Kumar , Asokan K , Pramanik A K
Published: August 2020

The structural, magnetic and dielectric properties have been investigated in 3d–5d based double perovskite Sr2FeIrO6 thin films deposited by pulse laser deposition technique. To understand the effect of strain, epitaxial films are grown with varying thickness as well as on different substrates i.e., SrTiO3 (100) and LaAlO3 (100). The films with highest thickness are found to be more relaxed. Atomic force microscope images indicate all films are of good quality where grain sizes increase with increase in film thickness. X-ray absorption (XAS) spectroscopy measurements indicate a Ir5+ charge state in present films while providing a detailed picture of hybridization between Fe/Ir-d and O-p orbitals. The bulk antiferromagnetic transition is retained in films though the transition temperature shifts to higher temperature. Both dielectric constant (ϵ
r) and loss (tan  δ) show change around the magnetic ordering temperatures of bulk Sr2FeIrO6 indicating a close relation between dielectric and magnetic behaviors. A Maxwell–Wagner type relaxation is found to follow over whole frequency range down to low temperature in present film. On changing the substrate i.e., LaAlO3 (100), the ϵ
r(T) and (tan  δ(T)) show almost similar behavior but ϵ
r shows a higher value which is due to an increased strain coming from high mismatch of lattice parameters.
Upconversion nanoparticles extending the spectral sensitivity of silicon photodetectors to λ = 1.5 μm
Authors: Xiang Hengyang , Zhou Lei , Lin Hung-Ju , Hu Zhelu , Zhao Ni , Chen Zhuoying
Published: August 2020

The telecommunication wavelength of λ = 1.5 μm has been playing an important role in various fields. In particular, performing photodetection at this wavelength is challenging, demanding more performance stability and lower manufacturing cost. In this work,
upconversion nanoparticle (UCNP)/Si hybrid photodetectors (hybrid PDs) are presented, made by integrating solution-processed Er3+-doped NaYF4 upconversion nanoparticles (UCNPs) onto a silicon photodetector. After optimization, we demonstrated that a layer of UCNPs can well lead to an effective spectral sensitivity extension without sacrificing the photodetection performance of the Si photodetector in the visible and near-infrared (near-IR) spectrum. Under λ = 1.5 μm illumination, the hybrid UCNPs/Si-PD exhibits a room-temperature detectivity of 6.15 × 1012 Jones and a response speed of 0.4 ms. These UCNPs/Si-PDs represent a promising hybrid strategy in the quest for low-cost and broadband photodetection that is sensitive in the spectrum from visible light down to the short-wave infrared.