bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of Ridge and Furrow Method of Planting on Groundnut Yield Attributes in Chittoor District of Andhra Pradesh, India
Authors: Chowdary K. Raghavendra , Jyotsna M. K. , Jyothi I. 
Published: April 2022

Climate change is putting increasing pressure on India's farmers' land and natural resources, which they rely on not just to feed the country but also to support their livelihoods. Approximately 30% of land is currently degraded, and rising temperatures mean agriculture will require 30% more water. Innovative approaches are emerging across India to assist farmers in adapting to climate change challenges and mitigating the effects of their farming practises. An innovative ridge and furrow planting pattern and its impact on ground nut crop production was carried out. The field experiment was conducted during the two consecutive Rabi and Kharif seasons of 2020 and 2021 to study ridge and furrow in-situ conservation system for Groundnut crop at farmer’s fields in Chittoor district of Andhra Pradesh under Southern agro-climatic region. Raised bed planting involves sowing of crops using raised bed maker alternated with furrows for irrigation. Bed width depends upon crop spacing usually ranging from 30 cm, and accommodates crop on raised bed. Raised beds require reshaping each year preferably before Kharif season. Bed planting reduces cost, and saves seed, fertilizer and irrigation water. It also increases water-use efficiency both under rainfed and irrigated scenarios because water moves laterally from furrows into beds thereby reducing evaporation losses. Further lesser incidence of pest and diseases as well as better aeration within furrows. Weed population reduced on ridge and furrow method of planting. The ridge-furrow method of planting groundnut has been reported to save seed and water by 25-30% and fertilizer by 25%, yield enhancement to the extent of 8-23% higher compared to the normal flatbed sowing method. Economic analysis revealed that the net profit was recorded higher under ridge and furrow system compared to normal flatbed sowing. Benefit–cost ratio (BCR) ratio was recorded under ridge and furrow system (5.13) while under flat sowing system (2.20) for the consecutive years respectively.
Surgical Resection for Colorectal Cancer Improves Survival in Uganda
Authors: Wismayer Richard , Kiwanuka Julius , Wabinga Henry , Odida Michael 
Published: April 2022

Introduction: In Uganda and other developing low-income countries in Sub-Saharan Africa, colorectal carcinoma (CRC) incidence and mortality rates are increasing whereas in high income developed countries, CRC rates are declining. Many patients do not have access to curative surgery and oncological treatment for CRC in Uganda. In this study, we compared the survival outcomes of patients who underwent curative surgery, and, if necessary, adjuvant chemotherapy to those who did not to assess the impact of surgery and oncology care on CRC in the resource-limited setting of a low-income developing country.
Methods: Participants with a diagnosis of CRC between 1 January 2008 and 31 December 2018 were included. These patients had linked data in the Kampala Cancer Registry and medical records from hospitals in Uganda. Data on whether the patients had or did not have curative surgery and adjuvant chemotherapy were obtained. Our outcome variable was survival at 3 years. We computed and compared survival using the log-rank test.
Results: Two hundred and forty seven patients were included in the study cohort. These were 177 (71.66%) patients that had curative surgery, while 70 (28.34%) had no curative surgery. Curative rectal cancer surgery had a better survival than no curative surgery (p=0.003). Curative colon cancer surgery tended to have a better survival than no surgery (p=0.137). Curative surgery and adjuvant chemotherapy showed better survival than no surgery with no adjuvant chemotherapy (p=0.007).
Conclusions: In a resource-limited environment, curative surgery and if necessary, combined with adjuvant chemotherapy improves survival. The findings in our study therefore serve to encourage the expansion of CRC care by improving the surgery and oncology infrastructure in resource-limited environments due to the increasing burden of CRC.
Improved Stability and Efficiency of Inverted Perovskite Solar Cell by Employing Nickel Oxide Hole Transporting Material Containing Ammonium Salt Stabilizer
Authors: Park Sungjin , Kim Dong Won , Park Soo Young 
Published: April 2022

AbstractNickel oxide (NiO) is one of the promising hole‐transporting materials for perovskite solar cells (PSCs). Despite the ongoing efforts to improve PSC performance with sol–gel NiO, there has been limited study on the usage and influences of stabilizers on NiO and the relevant performance of PSCs. Until now, most of the sol–gel NiO methods use chemical stabilizers based on strongly acidic or mild basic catalysts such as hydrochloric acid and monoethanolamine. However, it is evident that the remaining pH‐biased stabilizers in the film aggravate device stability. Therefore, it is imperative to develop a more stable and effective NiO, which can boost the performance of PSC. Here, the relatively neutral ammonium salt is utilized in NiO solution, which can improve the hole transport capability and stability of NiO. Under the optimum salt condition, energy level and hole conductivity are modulated favorably for hole transportation. Moreover, constructive interaction between the ammonium salt and perovskite enhances interfacial properties and reduces trap‐assisted recombination. Based on this novel NiO, the champion power conversion efficiency of 19.91% with an exceptionally high open‐circuit voltage of 1.13 V among the reported MAPbI3‐based PSCs is demonstrated. Furthermore, NiO with salt stabilizer secures long‐term device stability, maintaining 97% of initial power conversion efficiency (PCE) even after 800 h.
Fluorographene and Its Composites: Fundamentals, Electrophysical Properties, DFT Studies, and Advanced Applications
Authors: Borse Rahul Anil , Kale Manoj B. , Sonawane Shirish H. , Wang Yaobing 
Published: April 2022

AbstractFluorographenes (FGs) are the youngest family of graphene derivatives 2D layer‐structure, which has changed the hybridization state from sp2‐to‐sp3 carbon and unique CF bonds impacting physical and chemical properties. Due to various types of CF bonds, wide bandgap, tunable F/C ratios, and unique nanostructure, the FGs show attractive physicochemical properties. Owing to the extraordinary properties, the researchers have recently paid attention to exploring FGs into fluorographene composites (FG‐Cs) as a potential candidate for fundamental advances in the field of the energy system, optoelectronic, biomedical, and aeronautics. Despite their promise, in‐depth experimental and theoretical studies of FGs over FG‐Cs are not explored systematically. This review focuses on the recent experimental developments on FGs and FG‐Cs, including fundamentals and electrophysical properties, synthesis methods, conductivity, hydrophobicity, and magnetic nature. Further, for the validation, the theoretical studies, first‐principle study/density functional theory emphasize their real intrinsic activity, stability, and effects of F content, defects, and doping mechanism. Finally, the wide applications, energy systems to biomedical and optoelectronics to the aerospace industry, along with challenges and future perspectives, are also discussed. This review aims to conclude valuable insights into the fundamental science and perspective toward highly efficient FG‐C‐based catalysts engineering in advanced applications.
Metal‐Free Perovskite Piezoelectric Nanogenerators for Human–Machine Interfaces and Self‐Powered Electrical Stimulation Applications
Authors: Wu Han‐Song , Wei Shih‐Min , Chen Shuo‐Wen , Pan Han‐Chi , Pan Wei‐Pang , Huang Shih‐Min , Tsai Meng‐Lin , Yang Po‐Kang 
Published: April 2022

AbstractSingle crystal metal‐free halide perovskites have received great attention in recent years owing to their excellent piezoelectric and ferroelectric properties. However, the nanotoxicity and piezoelectricity within the nanoscale of such materials have yet been reported for the demonstration of practical applications. In this work, the observation of intrinsic piezoelectricity in metal‐free perovskite (MDABCO‐NH4I3) films using piezoresponse force microscopy (PFM) is reported. A cytotoxicity test is also performed on MDABCO‐NH4I3 to evaluate its low‐toxic nature. The as‐synthesized MDABCO‐NH4I3 is further integrated into a piezoelectric nanogenerator (PENG). The MDABCO‐NH4I3‐based PENG (MN‐PENG) exhibits optimal output voltage and current of 15.9 V and 54.5 nA, respectively. In addition, the MN‐PENG can serve as a self‐powered strain sensor for human–machine interface applications or be adopted in in vitro electrical stimulation devices. This work demonstrates a path of perovskite‐based PENG with high performance, low toxicity, and multifunctionality for future advanced wearable sensors and portable therapeutic systems.
Effect of Aromatic Solvents Residuals on Electron Mobility of Organic Single Crystals
Authors: Xue Guobiao , Peng Boyu , Ye Tao , Wu Jiake , Zhao Yujie , Liu Yujing , Yamada Hiroko , Chen Hongzheng , Li Hanying 
Published: April 2022

AbstractBalanced electron and hole transport properties are essential for various organic electrical/optoelectrical applications such as organic solar cells, complementary circuits, and light‐emitting transistors. However, the electron transport in organic semiconductor lags far behind the hole side, making it with vital significance to seek the factors that limit the electron mobility. Here, the authors demonstrate that the π‐conjugated solvents, as essential components in the widely‐used solution processing techniques, can significantly suppress the electron transport if they are not properly removed and trapped as residuals. Single crystals of typical p‐type materials exhibit a transition from p‐type behavior to ambipolar conductance via reducing the amount of solvent residuals, and the same effect is confirmed by varied p‐type materials and solvents. The highest electron mobility reaches 0.027 cm2 V−1 s−1 and 0.029 cm2 V−1 s−1 for 6,13‐bis(triisopropylsilylethynyl)pentacene and 5,15‐bis(triisopropylsilylethynyl)tetrabenzoporphyrin, respectively. This work discloses the non‐negligible existence of solvent residuals even in high quality, long‐range ordered organic single crystals, and further provides efficient strategies to harvest the n‐type behaviors of organic semiconductor materials.
Estimation of output measurement variances for error‐in‐variables model parameter estimation
Authors: Abdi Kaveh , McAuley Kimberley B. 
Published: April 2022

AbstractError‐in‐variables model (EVM) methods require information about variances of input and output measured variables when estimating the parameters in mathematical models for chemical processes. In EVM, using replicate experiments for estimating output measurement variances is complicated because true values of inputs may be different when multiple attempts are made to repeat an experiment. To address this issue, we categorize attempted replicate experiments as: (i) true replicates (TRs) when uncertain inputs are the same in replicated runs and (ii) pseudo replicates (PRs) when measured inputs are the same, but unknown true values of inputs are different. We propose methodologies to obtain output measurement variance estimates and associated parameter estimates for both situations. We also propose bootstrap methods for obtaining joint‐confidence information for the resulting parameter estimates. A copolymerization case study is used to illustrate the proposed techniques. We show that different assumptions noticeably affect the uncertainties in the resulting reactivity‐ratio estimates.
Diversification in the Rosales is influenced by dispersal, geographic range size, and pre‐existing species richness
Authors: Simpson Andrew G. , Wing Scott L. , Fenster Charles B. 
Published: April 2022

AbstractPremiseBiodiversity results from origination and extinction, justifying interest in identifying traits that influence this balance. Traits implicated in the success or failure of lineages include dispersal, colonization ability, and geographic range size. We investigated the impact of dispersal and range size on contemporary diversity in the Rosales.MethodsWe used the multiple‐state speciation and extinction (MuSSE) method to explore the effects on genus‐level diversification of two genus‐level traits (geographic range size and within‐genus proclivity to speciate) and two species traits (seed dispersal and growth habit) and the multiple hidden‐state speciation and extinction (MuHiSSE) method for species‐level associations. Finally, we conducted a PGLS (phylogenetic least‐squares) analysis to distinguish between speciation within genera versus origination of new genera.ResultsAt the species level, animal dispersal enhances diversification rate in both woody and herbaceous lineages, while woody lineages without animal dispersal have higher extinction rates than speciation rates. At the genus level, herbaceous taxa have positive diversification rates regardless of other character states. Diversification rate variation is also explained by two interactions: (1) a three‐way interaction between large geographic range, animal‐mediated dispersal, and high within‐genus species richness, whereby genera possessing all three traits have high diversification rates, and (2) a four‐way interaction by which the three‐way interaction is stronger in woody genera than in herbaceous genera.ConclusionsColonization ability may underlie the relationship between dispersal type and range size and may influence past diversification rates by decreasing extinction rates during late Cenozoic climate volatility. Thus, colonization ability could be used to predict future extinction risk to aid conservation.
Superlattices with coupled channels and transfer matrices
Authors: Anzaldo‐Meneses Alfonso 
Published: April 2022

AbstractWe study analytically threshold and resonance effects in superlattices using the well‐known transfer matrix technique. For this analysis we take advantage of a new parametrization of the scattering amplitudes. In particular, threshold effects, analogous to the so‐called “Wigner cusps” of nuclear reactions, follow when a channel is opened for non‐zero coupling. Sharp resonances of Lorenzian shape are also found only in the presence of coupling. It could be very interesting to look for experimental evidences of these effects. We expect that this approach allows to study systems with spin and under external magnetic fields.
S‐matrix network models for coherent waves in random media: construction and renormalization
Authors: Janssen Martin , Merkt Rainer , Weymer Andreas 
Published: April 2022

AbstractNetworks of random quantum scatterers (S‐matrices) form paradigmatic models for the propagation of coherent waves in random media. S‐matrix network models cover universal localization‐delocalization properties and have some advantages over more traditional Hamiltonian models. In particular, a straightforward implementation of real space renormalization techniques is possible. Starting from a finite elementary cell of the S‐matrix network, hierarchical network models can be constructed by recursion. The localization‐delocalization properties are contained in the flow of the forward scattering strength (‘conductance’) under increasing system size. With the aid of ‘small scale’ numerics qualitative aspects of the localization‐delocalization properties of S‐matrix network models can be worked out.
Critical level statistics of a quantum Hall system with Dirichlet boundary conditions
Authors: Potempa H. , Schweitzer L. 
Published: April 2022

AbstractWe investigate numerically the influence of Dirichlet boundary conditions on the nearest neighbor level spacing distribution P(s) of a two‐dimensional disordered tightbinding model in the presence of a strong perpendicular magnetic field. From the calculation of the second moment of P(s) it is shown that for Dirichlet boundary conditions, due to the presence of edge states, the position of the critical energy shifts with increasing system size to the location of the critical energy for periodic boundary conditions. An extrapolation to infinite system size results in different critical (scale independent) P(s) distributions for periodic and Dirichlet boundary conditions.
Electronic transport in disordered interacting systems
Authors: Vojta Thomas , Epperlein Frank 
Published: April 2022

AbstractWe numerically investigate the transport properties of disordered interacting electrons in three dimensions in the metallic as well as in the insulating phases. The disordered many‐particle problem is modeled by the quantum Coulomb glass which contains a random potential, long‐range unscreened Coulomb interactions and quantum hopping between different sites. We have recently developed the Hartree‐Fock based diagonalization (HFD) method which amounts to diagonalizing the Hamiltonian in a suitably chosen energetically truncated basis. This method allows us to investigate comparatively large systems. Here we calculate the combined effect of disorder and interactions on the dissipative conductance. We find that the qualitative influence of the interactions on the conductance depends on the relative disorder strength. For strong disorder interactions can significantly enhance the transport while they suppress the conductance for weak disorder.
Solving the Schrödinger equation on percolation structures by means of the equation of motion method
Authors: Dräger Julia , Halfpap Ole 
Published: April 2022

AbstractWe investigate the dynamical properties of the quantum percolation model at the critical percolation threshold pc in two dimensions by means of the spreading of a wave packet. We find that for t → ∞ the mean square displacement R2(t) converges to R2(t) ≃ 92. In order to obtain a microscopic insight we investigate the averaged squared wave function 〈|ψ(r,t)|2〉 for fixed time t and find that up to a crossover distance r× its spatial decay is given by a stretched exponential with exponent u ≃ 0.58. The exponent u agrees with the exponent dψ obtained recently for the corresponding time independent localization problem. Furthermore we find that the averaged moments 〈|ψ(r,t)|2q〉 for fixed time t scale in a multifractal way 〈|ψ(r,t)|2q〉 ∼ 〈|ψ(r,t)|2〉τ(q) with τ(q) ∼ qδ and δ ≃ 1.25 ± 0.05.
Transient increase of high momenta in quantum wave‐packet collisions
Authors: Brouard S. , Muga J.G. 
Published: April 2022

AbstractWe study the transient increase of the upper tail of the momentum distribution in quantum wave‐packet collisions with an analytically solvable model; in particular its dependence with the barrier strength and incident momentum. This effect is a classically forbidden, universal feature of all quantum collisions.
Can EPR‐correlations be used for the transmission of superluminal signals?
Authors: Mittelstaedt P. 
Published: April 2022

AbstractIn a compound quantum system with EPR–like correlations a measurement of one subsystem induces instantaneously changes of the other subsystem, irrespective of the relative distance of the two subsystems. We consider several arguments which were put forward in recent years in order to show that these nonlocal effects cannot be used for superluminal communication. It turns out that the arguments mentioned above are merely plausible but not really stringent and convincing. This means that the question in the title of this paper is still open.
The velocity of probability transport in quantum mechanics
Authors: Melloy G.F. , Bracken A.J. 
Published: April 2022

AbstractIn his study of the ‘time of arrival’ problem in the nonrelativistic quantum mechanics of a single particle, Allcock [1] noted that the direction of the probability flux vector is not necessarily the same as that of the mean momentum of a wave packet, even when the packet is composed entirely of plane waves with a common direction of momentum. Packets can be constructed, for example for a particle moving under a constant force, in which probability flows for a finite time in the opposite direction to the momentum. A similar phenomenon occurs for the Dirac electron. The maximum amount of probabilitiy backflow which can occur over a given time interval can be calculated in each case.
On the role of a limiting velocity in constructive spacetime axiomatics
Authors: Schelb U. 
Published: April 2022

AbstractThe issue of superluminal velocities is looked at from the point of view of a spacetime axiomatics. Such theories construct the relativistic spacetime picture from simple, empirically based postulates. One important task is the convincing introduction of coordinates in spacetime, to which end “radar coordinates” are used. For this the existence of a finite limiting velocity of signals is absolutely necessary, but it may be superluminal without producing conflicts with causality on this level.
The Nambu–Goto theory of closed bosonic strings moving in 1 + 3–dimensional Minkowski space: the quantum algebra of observables
Authors: Pohlmeyer K. 
Published: April 2022

AbstractA relevant part of the quantum algebra of observables for the closed bosonic strings moving in 1 + 3–dimensional Minkowski space is presented in the form of generating relations involving still one, as yet undetermined, real free parameter.
The Nambu‐Goto theory of closed bosonic strings moving in 1 + 3–dimensional Minkowski space: the construction of the quantum algebra of observables up to degree five
Authors: Handrich G. , Nowak C. 
Published: April 2022

AbstractThe quantum algebra of observables of closed bosonic strings moving in 1 + 3–dimensional Minkowski space is constructed up to degree five. All independent relations of degree four are computed; they involve three as yet undetermined parameters. Definitions and symbols are used as introduced in the above‐mentioned article.
On measuring gravitomagnetism via spaceborne clocks: a gravitomagnetic clock effect
Authors: Mashhoon B. , Gronwald F. , Theiss D.S. 
Published: April 2022

AbstractThe difference in the proper azimuthal periods of revolution of two standard clocks in direct and retrograde orbits about a central rotating mass is proportional to J/Mc2, where J and M are, respectively, the proper angular momentum and the mass of the source. It is shown that this circumstance is due to a special gravitomagnetic temporal structure around a rotating mass. In connection with this gravitomagnetic clock effect, we explore the possibility of using spaceborne standard clocks for detecting the gravitomagnetic field of the Earth.
Chiral supergravity and anomalies
Authors: Mielke Eckehard W. , Macías Alfredo 
Published: April 2022

AbstractSimilarly as in the Ashtekar approach, the translational Chern‐Simons term is, as a generating function, instrumental for a chiral reformulation of simple supergravity. After applying the algebraic Cartan relation between spin and torsion, the resulting canonical transformation induces not only a decomposition of the gravitational fields into selfdual and anti‐selfdual modes, but also a splitting of the Rarita‐Schwinger fields into their chiral parts in a natural way. In some detail, we also analyze the consequences for axial and chiral anomalies.
Einstein‐Proca model: spherically symmetric solutions
Authors: Obukhov Yuri N. , Vlachynsky Eugen J. 
Published: April 2022

AbstractThe Proca wave equation describes a classical massive spin 1 particle. We analyze the gravitational interaction of this vector field. In particular, the spherically symmetric solutions of the Einstein‐Proca coupled system are obtained numerically. Although at infinity the metric field approaches the usual Schwarzschild (Reissner‐Nordström) limit, we demonstrate the absence of black hole type configurations.