bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biofabrication using maize protein: 3D printing using zein formulations
Authors: Tavares-Negrete Jorge Alfonso , Aceves-Colin Alberto Emanuel , Rivera-Flores Delia Cristal , Díaz-Armas Gladys Guadalupe , Mertgen Anne-Sophie , Trinidad-Calderón Plinio Alejando , Olmos-Cordero Jorge Miguel , Gómez-López Elda Graciela , Pérez-Carrillo Esther , Escobedo-Avellaneda Zamantha Judith , Tamayol Ali , Moisés Alvarez Mario , Trujillo-de Santiago Grissel 
Published: July 2020

AbstractThe use of three-dimensional (3D) printing for biomedical applications has expanded exponentially in recent years. However, the current portfolio of 3D printable inks is still limited. For instance, only a few protein matrices have been explored as printing/bioprinting materials. Here, we introduce the use of zein, the primary constitutive protein in maize seeds, as a 3D-printable material. Zein-based inks were prepared by dissolving commercial zein powder in ethanol with or without polyethylene glycol (PEG400) as a plasticizer. The rheological characteristics of our materials, studied during 21 days of aging/maturation, showed an increase in the apparent viscosity as a function of time in all formulations. The addition of PEG 400 decreased the apparent viscosity. Inks with and without PEG400 and at different maturation times were tested for printability in a BioX bioprinter. We optimized the 3D printing parameters for each ink formulation in terms of extrusion pressure and linear printing velocity. Higher fidelity structures were obtained with inks that had maturation times of 10 to 14 days. We present different proof-of-concept experiments to demonstrate the versatility of the engineered zein inks for diverse biomedical applications. These include printing of complex and/or free-standing 3D structures, materials for controlled drug release, and scaffolds for cell culture.
Towards chemical accuracy for alchemical free energy calculations with hybrid physics-based machine learning / molecular mechanics potentials
Authors: Rufa Dominic A. , Bruce Macdonald Hannah E. , Fass Josh , Wieder Marcus , Grinaway Patrick B. , Roitberg Adrian E. , Isayev Olexandr , Chodera John D. 
Published: July 2020

AbstractAlchemical free energy methods with molecular mechanics (MM) force fields are now widely used in the prioritization of small molecules for synthesis in structure-enabled drug discovery projects because of their ability to deliver 1–2 kcal mol−1accuracy in well-behaved protein-ligand systems. Surpassing this accuracy limit would significantly reduce the number of compounds that must be synthesized to achieve desired potencies and selectivities in drug design campaigns. However, MM force fields pose a challenge to achieving higher accuracy due to their inability to capture the intricate atomic interactions of the physical systems they model. A major limitation is the accuracy with which ligand intramolecular energetics—especially torsions—can be modeled, as poor modeling of torsional profiles and coupling with other valence degrees of freedom can have a significant impact on binding free energies. Here, we demonstrate how a new generation of hybrid machine learning / molecular mechanics (ML/MM) potentials can deliver significant accuracy improvements in modeling protein-ligand binding affinities. Using a nonequilibrium perturbation approach, we can correct a standard, GPU-accelerated MM alchemical free energy calculation in a simple post-processing step to efficiently recover ML/MM free energies and deliver a significant accuracy improvement with small additional computational effort. To demonstrate the utility of ML/MM free energy calculations, we apply this approach to a benchmark system for predicting kinase:inhibitor binding affinities—a congeneric ligand series for non-receptor tyrosine kinase TYK2 (Tyk2)—wherein state-of-the-art MM free energy calculations (with OPLS2.1) achieve inaccuracies of 0.93±0.12 kcal mol−1in predicting absolute binding free energies. Applying an ML/MM hybrid potential based on the ANI2x ML model and AMBER14SB/TIP3P with the OpenFF 1.0.0 (“Parsley”) small molecule force field as an MM model, we show that it is possible to significantly reduce the error in absolute binding free energies from 0.97 [95% CI: 0.68, 1.21] kcal mol−1(MM) to 0.47 [95% CI: 0.31, 0.63] kcal mol−1(ML/MM).
In vitroreduction ofPlasmodium falciparumgametocytes byArtemisia spp.tea infusions
Authors: Snider Danielle , Weathers Pamela J. 
Published: July 2020

AbstractIn this study, we showedin vitroevidence that supports the efficacy ofA. annuaandA. afratea infusions used in a 2015 clinical trial not only for clearing asexualPlasmodium falciparumparasites, but also for eliminating sexual gametocytes.P. falciparumNF54 was grownin vitro,synchronized, and induced to form gametocytes using N-acetylglucosamine. Cultures during asexual, early, and late stage gametogenesis were treated with artemisinin, methylene blue, andArtemisia annuaandA. afratea infusions (5g DW/L) using cultivars that contained 0-283 μM artemisinin. Asexual parasitemia and gametocytemia were analyzed microscopically. Gametocyte morphology was also scored. Markers of early(PfGEXP5)and late stage(Pfs25)gametocyte gene expression were also measured using RT-qPCR. BothA. annuaandA. afratea infusions reduced gametocytemiain vitro, and the effect was mainly artemisinin dependent. Expression levels of both marker genes were reduced with the effect mainly attributed to artemisinin content of the our testedArtemisiacultivars. Tea infusions of both species also inhibited asexual parasitemia and although mainly artemisinin dependent, there was a weak antiparasitic effect from artemisinin-deficientA. afra. These results showed thatA. annuaand to a lesser extent,A. afra,inhibited parasitemia and gametogenesisin vitro,and results are consistent with earlier observed clinical results.
Bringing the pancreas patient back to the bench:Ex vivoculture of intact human patient derived pancreatic tumour tissue
Authors: Kokkinos John , Sharbeen George , Haghighi Koroush S. , Ignacio Rosa Mistica C. , Kopecky Chantal , Gonzales-Aloy Estrella , Youkhana Janet , Pandzic Elvis , Boyer Cyrille , Davis Thomas P. , Butler Lisa M. , Goldstein David , McCarroll Joshua A. , Phillips Phoebe A. 
Published: July 2020

AbstractThe poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is attributed to the highly fibrotic stroma and complex multi-cellular microenvironment that is difficult to fully recapitulate in pre-clinical human models. To fast-track translation of therapies and to inform personalised medicine, we aimed to develop a whole-tissueex vivoexplant model that maintains viability, 3D multicellular architecture, and microenvironmental cues present in human pancreatic tumours. Patient-derived surgically-resected PDAC tissue was cut into 2 mm explants, cultured on gelatin sponges, and grown for 12 days. Immunohistochemistry revealed that human PDAC tissue explants were viable for 12 days and maintained their original tumour, stromal and extracellular matrix architecture. As proof-of-principle, human PDAC tissue explants responded to Abraxane®treatment with a 3.7-fold increase in cell-death (p=0.0007). PDAC explants were also transfected with polymeric nanoparticles+Cy5-siRNA and we observed abundant cytoplasmic distribution of nanoparticle+Cy5-siRNA throughout the PDAC explant tissue. Our novel model retains the 3D architecture of human pancreatic tumours and has several advantages over standard organoids: presence of functional multi-cellular stroma and fibrosis and no tissue manipulation, digestion, or artificial propagation of organoids. This provides an unprecedented opportunity to study PDAC biology, tumour-stromal interactions and rapidly assess therapeutic response that could drive personalised treatment for PDAC.
STIL-a novel link in Shh and Wnt signaling, endowing oncogenic and stem like attributes to colorectal cancer
Authors: Pradhan Tapas , Kumar Vikas , Evangeline Surya H , Krishna R , John Samu , Jissa VT , Anjana S , Chandramohan K , Nair S Asha 
Published: July 2020

AbstractDiscovery of potent gene regulating tumorigenesis and drug resistance is of high clinical importance. STIL is an oncogene, however its molecular insights and role in colorectal oncogenesis are unknown. In this study we have explored role of STIL in tumorigenesis and studied its molecular targets in colorectal cancer (CRC). STIL silencing reduced proliferation and tumor growth in CRC. Further, STIL was found to regulate stemness markers CD133 & CD44 and drug resistant markers Thymidylate synthase, ABCB1 & ABCG2 both in in-vitro and in-vivo CRC models. In addition, over expression of STIL mRNA was found to be associated with reduced disease free survival in CRC cases. To our surprise we observed an Shh independent regulation of stemness and drug resistant genes mediated by STIL. Interestingly, we found an Shh independent regulation of β-catenin mediated by STIL via p-AKT, which partially answers Shh independent regulatory mechanism of CSC markers by STIL. Our study suggest an instrumental role of STIL in molecular manifestation of CRC and progression.
Diffraction gratings with two-orders-of-magnitude-enhanced dispersion rates for sub-meV resolution soft X-ray spectroscopy
Authors: Shvyd'ko Yuri 
Published: July 2020

Diffraction gratings with large angular dispersion rates are central to obtaining high spectral resolution in grating spectrometers operating over a broad spectral range from infrared to soft X-ray domains. The greatest challenge is of course to achieve large dispersion rates in the short-wavelength X-ray domain. Here it is shown that crystals in non-coplanar asymmetric X-ray Bragg diffraction can function as high-reflectance broadband soft X-ray diffraction gratings with dispersion rates that are at least two orders of magnitude larger than those that are possible with state-of-the-art man-made gratings. This opens new opportunities to design and implement soft X-ray resonant inelastic scattering (RIXS) spectrometers with spectral resolutions that are up to two orders of magnitude higher than what is currently possible, to further advance a very dynamic field of RIXS spectroscopy, and to make it competitive with inelastic neutron scattering. Examples of large-dispersion-rate crystal diffraction gratings operating near the 930 eV L
3 absorption edge in Cu and of the 2.838 keV L
3-edge in Ru are presented.
Evolution of conformal antenna design with the aid of probability improved crow search algorithm
Authors: Nagendra Nama Ajay , Pappula Lakshman 
Published: July 2020

PurposeThe issues of radiating sources in the existence of smooth convex matters by such objects are of huge significance in the modeling of antennas on structures. Conformal antenna arrays are necessary when an antenna has to match to certain platforms. A fundamental problem in the design is that the possible surfaces for a conformal antenna are infinite in number. Furthermore, if there is no symmetry, each element will see a different environment, and this complicates the mathematics. As a consequence, the element factor cannot be factored out from the array factor.Design/methodology/approachThis paper intends to enhance the design of the conformal antenna. Here, the main objective of this task is to maximize the antenna gain and directivity from the first-side lobe and other side-lobes in the two way radiation pattern. Thus the adopted model is designed as a multiobjective concern. In order to attain this multiobjective function, both the element spacing and the radius of each antenna element should be optimized based on the probability of the Crow Search Algorithm (CSA). Thus the proposed method is named Probability Improved CSA (PI-CSA). Here, the First Null Beam Width (FNBW) and Side-Lobe Level (SLL) are minimized. Moreover, the adopted scheme is compared with conventional algorithms, and the results are attained.FindingsFrom the analysis, the gain of the presented PI-CSA scheme in terms of best performance was 52.68% superior to ABC, 25.11% superior to PSO, 13.38% superior to FF and 3.21% superior to CS algorithms. Moreover, the mean performance of the adopted model was 62.94% better than ABC, 13.06% better than PSO, 24.34% better than FF and 10.05% better than CS algorithms. By maximizing the gain and directivity, FNBW and SLL were decreased. Thus, the optimal design of the conformal antenna has been attained by the proposed PI-CSA algorithm in an effective way.Originality/valueThis paper presents a technique for enhancing the design of the conformal antenna using the PI-CSA algorithm. This is the first work that utilizes PI-CSA-based optimization for improving the design of the conformal antenna.
Simplified analysis of cable-stayed bridges with longitudinal viscous dampers
Authors: Li Xu , Li Jun , Zhang Xiaoyi , Gao Jianfeng , Zhang Chao 
Published: July 2020

PurposeViscous dampers are commonly used in large span cable-stayed bridges to mitigate seismic effects and have achieved great success.Design/methodology/approachHowever, the nonlinear analysis on damper parameters is usually computational intensive and nonobjective. To address these issues, this paper proposes a simplified method to determine the viscous damper parameters for double-tower cable-stayed bridges. An empirical formula of the equivalent damping ratio of viscous dampers is established through decoupling nonclassical damping structures and linearization of nonlinear viscous dampers. Shaking table tests are conducted to verify the feasibility of the proposed method. Moreover, this simplified method has been proved in long-span cable-stayed bridges.FindingsThe feasibility of this method is verified by the simplified model shaking table test. This simplified method for determining the parameters of viscous dampers is verified in cable-stayed bridges with different spans.Originality/valueThis simplified method has been validated in cable-stayed bridges with various spans.
Public investment and private sector performance in Nigeria
Authors: Adeosun Opeoluwa Adeniyi , Orisadare Monica Adele , Fagbemi Fisayo , Adedokun Sikiru Adetona 
Published: July 2020

PurposeThis study explores the asymmetric linkage between public investment and private sector performance in Nigeria. This is due to the presence of nonlinear structures in the behavior of domestic investment series with evidences of structural time breaks, which fall within periods of global financial crises and oil shocks.Design/methodology/approachMain data on gross capital formation, gross fixed capital formation, domestic credit to private sector, domestic credit to private sector by banks are used for the study span through 1986 to 2017. Evidence of asymmetry spurs the study to adopt the nonlinear autoregressive distributed lag, asymmetric generalized impulse response and variance decomposition and asymmetric granger causality techniques.FindingsIt is shown that positive (negative) investment shocks exhibit a non-negligible and substantial stimulating (dampening) influence on the long-run performance of private sector in the economy. However, there is evidence that negative investment shocks portend a positive influence on the performance of private sector in the short run. This suggests that negative shocks to investment may not dampen the effectiveness of private sector in the short run, and this thus brings to bear the debate on the tenability of public investment as a potent counter cyclical tool in enhancing short-run private sector growth. The nonlinear granger causality also shows a unidirectional nonlinear causality from public investment to private sector performance. However, there is no evidence of bidirectional nonlinear causality.Originality/valueThis study provides quantitative evidence that Nigeria still depends exclusively on public investment, and as an oil-based rentier economy its economic diversification drive still remains bleak.
Supply chain integration and its impact on supply chain agility and organizational flexibility in manufacturing firms
Authors: Shukor Ahmad Azwan Ahmad , Newaz Md. Shah , Rahman Muhammad Khalilur , Taha Azni Zarina 
Published: July 2020

PurposeThis study investigates the impact of environmental uncertainty and organizational ambidexterity on supply chain integration and its relationship between supply chain agility and organizational flexibility in the manufacturing firms.Design/methodology/approachThe data were collected from 526 managers in services and manufacturing industry in Kuala Lumpur. The partial least square (SmartPLS 3.0) tool was applied through the use of the structural equation modeling (SEM) technique.FindingsThe results revealed that a strong relationship exist between environmental uncertainty and supply chain integrations including customer, supplier and internal integration. Organizational ambidexterity has a significant relationship with supply chain integration. Supply chain integrations were shown to have a positive impact on the firm's supply chain agility and organizational flexibility.Originality/valueThe findings may assist to establish a set of key drivers for enhancing supply chain agility and organizational flexibility as a supply chain management initiative in the manufacturing and service industry.
Insurrection training for post-human politics
Authors: Nold Christian 
Published: July 2020

PurposeThe purpose of this paper is to articulate an ontological anarchist approach for an engaged post-human politics and present insurrection training as a pragmatic tool for researchers to directly transform the world.Design/methodology/approachThe paper analyses how post-humanism has been criticised for dissolving political agency. It shows that this is due to the way post-humanism has been framed as sensitising and including non-humans into liberal politics. Instead, the paper examines anarchist-influenced post-humanism and combines this with the notion of multiple ontologies and ontological interventions. The paper presents the notion of insurrection training as offering the possibility for researchers to become emotionally sensitised to ontological difference. A case study of the “Seeds of Hope East Timor Ploughshares action” (1996) is used to illustrate what insurrection training and ontological interventions look like in practice. Finally, the paper makes suggestions as to how post-human researchers can apply this approach in their everyday lives.FindingsThe paper suggests that beyond a liberal framing of post-humanism as inclusion, there is also an ontological anarchist post-humanism that can support transformative impacts in the world. This form of post-humanism offers specificity of intervention and reflexive training practices. Insurrection training can offer new possibilities for post-humanist researchers: experience ontological difference, de-trivialise the everyday, connect to social movements, make post-human politics “doable” and offer “direct” change.Originality/valueThe paper addresses discussions that claim post-humanism is disabling political change. Its contribution is to map an anarchist post-humanism and extend this with concepts of multiple ontologies. It proposes the notion of insurrection training which places attention on the role of the researcher as an active agent that needs to be sensitised to ontological difference to carry out interventions. A case study of direct action illustrates what ontological intervention and insurrection training look like in practice. The case study suggests that insurrection training is an everyday performative practice that integrates and negotiates the personal, material and political. Finally, the paper suggests how researchers can adopt such an approach in their everyday lives.
The sustainability of Swedish fiscal policy: a re-examination
Authors: Ndoricimpa Arcade 
Published: July 2020

PurposeThis study reexamines the sustainability of fiscal policy in Sweden.Design/methodology/approachTo test the sustainability of fiscal policy, two approaches are used; the methodology of Kejriwal and Perron (2010), testing for multiple structural changes in a cointegrated regression model and time-varying cointegration test of Bierens and Martins (2010), and Martins (2015).FindingsUsing the first approach of testing for multiple structural changes in a cointegrated regression model, the results indicate that government spending and revenue are cointegrated with two breaks. An estimation of a two-break long-run model shows that the slope coefficient increases from 0.678 to 0.892 from the first to the second regime, implying that fiscal deficits were weakly sustainable in the first two regimes, from 1800 to 1943, and from 1944 to 1974. Further, results from time-varying cointegration test indicate that cointegration between spending and revenue in Sweden is time-varying. Fiscal deficits were found to be unsustainable for the periods 1801–1811, 1831–1838, 1853–1860 , 1872–1882, 1897–1902, 1929–1940 and 1976–1982 and weakly sustainable over the rest of the study period.Research limitations/implicationsA number of implications arise from this study: (1) Accounting for breaks in cointegration analysis and in the estimation of the level relationship between spending and revenue is very important because ignoring breaks may lead to an overestimated slope coefficient and hence a bias on the magnitude of fiscal deficit sustainability. (2) In testing for cointegration between spending and revenue, assuming a constant cointegrating slope when it is actually time-varying can also be misleading because deficits can be sustainable for a period of time and unsustainable over another period.Originality/valueThe contribution of this study is three-fold; first, the study uses a long series of annual data spanning over a period of two centuries, from 1800 to 2011. Second, because of the importance of structural change in economics, to examine the existence of a level relationship between spending and revenue, the study uses the methodology of Kejriwal and Perron (2010) to test for multiple structural changes in a cointegrated regression model, as well as time-varying cointegration of Bierens and Martins (2010) and Martins (2015).
Organizational commitment and work-related implementation of enterprise social networks (ESNs): the mediating roles of employees' organizational concern and prosocial values
Authors: Olfat Mohammad , Shokouhyar Sajjad , Ahmadi Sadra , Tabarsa Gholam Ali , Sedaghat Atiye 
Published: July 2020

PurposeThis study, based on the cognitive dissonance and commitment theories, aims to show that employees with high organizational commitment take more advantage of enterprise social networks (ESNs) due to work-related motivations. Furthermore, this study used the tricomponent attitude model to show that the employees' organizational concern and prosocial values mediate the impact of the organizational commitment on the work-related use of an ESN.Design/methodology/approachIn all, 361 employees from seven Iranian companies using different ESN software packages were surveyed. The validity of the hypotheses was evaluated using partial least square–structural equation modeling (PLS-SEM).FindingsThe results of this study confirm that the employees' organizational commitment has a positive impact on their work-related use of the relevant ESN directly and through the mediating roles of their organizational concern and prosocial values.Originality/valuePrevious studies have carefully addressed the role of organizational commitment in the implementation of conventional information systems. However, this is among the few studies addressing the role of commitment in the work-related implementation of ESNs. The results of this study shed light on how employees with a high level of commitment toward the organizations for which they work take advantage of ESNs due to a work-related motivation for the accomplishment of their duties, for bringing benefits into the organization and for helping their coworkers.