16,732 results match your criteria boundary conditions


Terminal heterocyst differentiation in the Anabaena patA mutant as a result of post-transcriptional modifications and molecular leakage.

PLoS Comput Biol 2022 Aug 15;18(8):e1010359. Epub 2022 Aug 15.

Grupo Interdisciplinar de Sistemas Complejos (GISC) and Departamento de Matemáticas, Universidad Carlos III de Madrid, Leganés, Spain.

The Anabaena genus is a model organism of filamentous cyanobacteria whose vegetative cells can differentiate under nitrogen-limited conditions into a type of cell called heterocyst. These heterocysts lose the possibility to divide and are necessary for the colony because they can fix and share environmental nitrogen. In order to distribute the nitrogen efficiently, heterocysts are arranged to form a quasi-regular pattern whose features are maintained as the filament grows. Read More

View Article and Full-Text PDF

Yield gap analysis of rainfed alfalfa in the United States.

Front Plant Sci 2022 27;13:931403. Epub 2022 Jul 27.

Department of Agronomy, Kansas State University, Manhattan, KS, United States.

The United States (US) is the largest alfalfa ( L.) producer in the world. More than 44% of the US alfalfa is produced under rainfed conditions, although it requires a relatively high amount of water compared to major field crops. Read More

View Article and Full-Text PDF

How empowering leadership influences medical workers' work-family conflict in the post-pandemic era: A moderated mediation model of leadership "black box".

Front Psychol 2022 28;13:870753. Epub 2022 Jul 28.

School of Economic and Management, University of Chinese Academy of Sciences, Beijing, China.

After experiencing the COVID-19 pandemic, the status and mechanisms of leadership, and the challenges for medical workers in terms of family-work conflicts, have caused widespread concern. In the post-pandemic era, based on role theory and the stressor-detachment model, this paper seeks to break the "black box" of negative effects that can be caused by leadership, research the mechanism and boundary conditions of those negative effects, and explore factors to reduce those negative effects. We recruited 1,010 Chinese medical workers fighting COVID-19 on the frontline. Read More

View Article and Full-Text PDF

Reformulating the susceptible-infectious-removed model in terms of the number of detected cases: well-posedness of the observational model.

Philos Trans A Math Phys Eng Sci 2022 Oct 15;380(2233):20210306. Epub 2022 Aug 15.

Department of Mathematics, School of Mathematical and Physical Sciences, University of Sussex, Brighton, East Sussex BN1 9QH, UK.

Compartmental models are popular in the mathematics of epidemiology for their simplicity and wide range of applications. Although they are typically solved as initial value problems for a system of ordinary differential equations, the observed data are typically akin to a boundary value-type problem: we observe some of the dependent variables at given times, but we do not know the initial conditions. In this paper, we reformulate the classical susceptible-infectious-recovered system in terms of the number of detected positive infected cases at different times to yield what we term the observational model. Read More

View Article and Full-Text PDF
October 2022

Diel change in inorganic nitrogenous nutrient dynamics and associated oxygen stoichiometry along the Pearl River Estuary.

Water Res 2022 Aug 5;222:118954. Epub 2022 Aug 5.

State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China; State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China.

The reactive nitrogen (N) emitted from continents significantly perturbs the pristine N cycle around the land-ocean boundary resulting in eutrophication and hypoxia. As nutrients are transported downstream through an estuary, various types of biological processes co-occur to modulate nitrogen speciation to influence the biogeochemical habitats for downstream microorganisms. We surveyed the Pearl River Estuary to examine the N transfer dynamics among nitrogen species with considering process-specific oxygen production and consumption. Read More

View Article and Full-Text PDF

Constructing the boundary between potent and ineffective siRNAs by MG-algorithm with C-features.

BMC Bioinformatics 2022 Aug 13;23(1):337. Epub 2022 Aug 13.

State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, People's Republic of China.

Background: In siRNA based antiviral therapeutics, selection of potent siRNAs is an indispensable step, but these commonly used features are unable to construct the boundary between potent and ineffective siRNAs.

Results: Here, we select potent siRNAs by removing ineffective ones, where these conditions for removals are constructed by C-features of siRNAs, C-features are generated by MG-algorithm, Icc-cluster and the different combinations of some commonly used features, MG-algorithm and Icc-cluster are two different algorithms to search the nearest siRNA neighbors. For the ineffective siRNAs in test data, they are removed from test data by I-iteration, where I-iteration continually updates training data by adding these successively removed siRNAs. Read More

View Article and Full-Text PDF

Validation of the Reduced Unified Continuum Formulation Against In Vitro 4D-Flow MRI.

Ann Biomed Eng 2022 Aug 13. Epub 2022 Aug 13.

Department of Bioengineering, Stanford University, Clark Center E1.3 318 Campus Drive, Stanford, CA, 94305-5428, USA.

We previously introduced and verified the reduced unified continuum formulation for vascular fluid-structure interaction (FSI) against Womersley's deformable wall theory. Our present work seeks to investigate its performance in a patient-specific aortic setting in which assumptions of idealized geometries and velocity profiles are invalid. Specifically, we leveraged 2D magnetic resonance imaging (MRI) and 4D-flow MRI to extract high-resolution anatomical and hemodynamic information from an in vitro flow circuit embedding a compliant 3D-printed aortic phantom. Read More

View Article and Full-Text PDF

Finite element analysis of mitral valve annuloplasty in Barlow's disease.

J Biomech 2022 Jul 25;142:111226. Epub 2022 Jul 25.

Department of Structural Engineering, Norwegian University of Science and Technology, Trondheim, Norway. Electronic address:

Barlow's Disease affects the entire mitral valve apparatus causing mitral regurgitation. Standard annuloplasty procedures lead to an average of 55% annular area reduction of the end diastolic pre-operative annular area in Barlow's diseased valves. Following annular reduction, mitral valvuloplasty may be needed, usually with special focus on the posterior leaflet. Read More

View Article and Full-Text PDF

High precision compact numerical approximation in exponential form for the system of 2D quasilinear elliptic BVPs on a discrete irrational region.

MethodsX 2022 23;9:101790. Epub 2022 Jul 23.

Department of Mathematics, Maitreyi College, University of Delhi, Delhi, 110021, India.

This article presents a new approximation of order four in exponential form for two-dimensional (2D) quasilinear partial differential equation (PDE) of elliptic form with solution domain being irrational. It is further extended for application to a system of quasilinear elliptic PDEs with Dirichlet boundary conditions (DBCs). The main highlights of the method framed in this article are as under:•It uses a 9-point stencil with unequal mesh to approach the solution. Read More

View Article and Full-Text PDF

Design of Under-Actuated Soft Adhesion Actuators for Climbing Robots.

Sensors (Basel) 2022 Jul 28;22(15). Epub 2022 Jul 28.

Changzhou Vocationnal Institute of Industry Technology, Changzhou 213018, China.

Since climbing robots mainly rely on adhesion actuators to achieve adhesion, robust adhesion actuators have always been the challenge of climbing robot design. A novel under-actuated soft adhesion actuator (USAA) proposed in this paper for climbing robots can generate adhesion through robot's load applied to the actuator. The actuator is composed of a soft film/substrate structure with an annular groove on the substrate and a cavity on the soft film. Read More

View Article and Full-Text PDF

Estimation of Bond Strength and Effective Bond Length for the Double Strap Joint between Carbon Fiber Reinforced Polymer (CFRP) Plate and Corroded Steel Plate.

Polymers (Basel) 2022 Jul 29;14(15). Epub 2022 Jul 29.

School of Civil Engineering, Xi'an University of Architecture & Technology, Xi'an 710055, China.

In this paper, we examine the development of the estimation models of bond strength and effective bond length for a double strap joint between carbon fiber reinforced polymer (CFRP) plate and corroded steel plate. The experimental study on the bond behavior between CFRP plate and corroded steel plate is summarized first and the analytical interfacial bond-slip model for CFRP plate externally bonded to corroded steel plate is proposed. Based on the theoretical stress analysis for the CFRP plate-corroded steel plate double-lap joint, the piecewise expressions of the interfacial shear stress and the normal peel stress of the interface between CFRP plate and corroded steel plate were established. Read More

View Article and Full-Text PDF

Modeling of Internal Geometric Variability and Statistical Property Prediction of Braided Composites.

Materials (Basel) 2022 Aug 3;15(15). Epub 2022 Aug 3.

School of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China.

Due to the advantages of high specific strength, specific stiffness, and excellent fatigue resistance, carbon fiber reinforced braided composites have been widely applied in engineering. Since the molding process of braided composites is complex and immature, substantial variability of the internal geometry exists in composites, in which the yarn path with uncertainty is a main factor, so it is necessary to establish an uncertainty model to study the influence of randomness of the yarn path on mechanical properties, which is significantly related to the fatigue resistance properties of composite. An uncertain mesoscopic model with uniform distribution of yarn paths is proposed. Read More

View Article and Full-Text PDF

Experimental Study on Carbonation of Cement-Based Materials in Underground Engineering.

Materials (Basel) 2022 Jul 29;15(15). Epub 2022 Jul 29.

School of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China.

The corrosive water environment has a decisive influence on the durability of a diversion tunnel lining. In this paper, the effects of carbonation on cement-based materials in water-immersion and saturated-humidity environments were studied by increasing the CO concentration. The results show that under conditions of water-immersion and saturated humidity, the color of the non-carbonation region is dark, while the carbonation region is gray, and the color boundary is obvious. Read More

View Article and Full-Text PDF

Rheology and Tribology of Ethylcellulose-Based Oleogels and W/O Emulsions as Fat Substitutes: Role of Glycerol Monostearate.

Foods 2022 Aug 7;11(15). Epub 2022 Aug 7.

Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.

Rheological and tribological properties of oleogels and water-in-oil (W/O) emulsions are important for application in fat substitutes. This study investigated the roles of glycerol monostearate (GMS) in tailoring the structural, rheological and tribological properties of ethylcellulose (EC)-based oleogels and W/O emulsions as potential fat substitutes. The addition of GMS contributed to more round and compact oil pores in oleogel networks. Read More

View Article and Full-Text PDF

Boundary Conditions Cause Different Generic Bifurcation Structures in Turing Systems.

Authors:
Thomas E Woolley

Bull Math Biol 2022 Aug 11;84(9):101. Epub 2022 Aug 11.

Cardiff School of Mathematics, Cardiff University, Senghennydd Road, Cardiff, CF24 4AG, UK.

Turing's theory of morphogenesis is a generic mechanism to produce spatial patterning from near homogeneity. Although widely studied, we are still able to generate new results by returning to common dogmas. One such widely reported belief is that the Turing bifurcation occurs through a pitchfork bifurcation, which is true under zero-flux boundary conditions. Read More

View Article and Full-Text PDF

Oligodendrocyte tethering effect on hyperelastic 3D response of axons in white matter.

J Mech Behav Biomed Mater 2022 Aug 2;134:105394. Epub 2022 Aug 2.

Mechanical and Aerospace Engineering, Rutgers University-New Brunswick, Piscataway, NJ, 08854, USA. Electronic address:

A novel finite element model is proposed to study the mechanical response of axons embedded in extracellular matrix when subjected to tensile loads under purely non-affine kinematic boundary conditions. Ogden hyperelastic material model describes the axons and the extracellular matrix material characterizations. Two axon-glia tethering scenarios in white matter are studied a single oligodendrocyte (single-OL) with multiple connections a multi-oligodendrocyte (multi-OL) one. Read More

View Article and Full-Text PDF

Failure to learn from failure is mitigated by loss-framing and corrective feedback: A replication and test of the boundary conditions of the tune-out effect.

J Exp Psychol Gen 2022 Aug;151(8):e19-e25

Institute for Management and Organization, Leuphana University Luneburg.

Do people learn from failure or do they mentally "tune-out" upon failure feedback, which in turn undermines learning? Recent research (Eskreis-Winkler & Fishbach, 2019) has suggested the latter, whereas research in educational and work settings indicates that failure can lead to more learning than can success and error-free performance. We conducted two preregistered experiments to replicate the tune-out effect and to test two potential boundary conditions (N = 520). The tune-out effect fully replicated in those experimental conditions that represented close replications of the original study, underscoring the reliability of the original effect. Read More

View Article and Full-Text PDF

[Intersectoral care: sector-linking approaches or a shifting of the sector boundary].

Authors:
Andreas Köhler

Inn Med (Heidelb) 2022 Aug 11. Epub 2022 Aug 11.

Spitzenverband Fachärzte Deutschlands e. V. (SpiFa), Robert-Koch-Platz 9, 10115, Berlin, Deutschland.

The coalition agreement between the German Social Democratic Party (SPD), Alliance 90/The Greens (Bündnis 90/Die Grünen), and the Free Democratic Party (FDP) states: "In order to promote the outpatientization of services that have so far been unnecessarily provided as inpatient care, we will swiftly implement sectoral remuneration for suitable services by means of so-called hybrid DRGs" (DRG, diagnosis-related group). More details are not known as yet. At this stage, another reform is surpassing the expectations that must inevitably arise from the coalition agreement, not least and especially for the care of internal medical conditions: The reform of Section 115b of Book V of the German Social Code (SGB V) and, thus, the revision of the catalog of operations that can be performed on an outpatient basis and interventions that can be performed on an inpatient basis. Read More

View Article and Full-Text PDF

Low-Frequency Vibrational Spectroscopy and Quantum Mechanical Simulations of the Crystalline Polymorphs of the Antiviral Drug Ribavirin.

Mol Pharm 2022 Aug 11. Epub 2022 Aug 11.

Department of Chemistry, Syracuse University, 1-133 Center for Science and Technology, Syracuse, New York 13244-4100, United States.

Crystal polymorphism is a common phenomenon in pharmaceutical solids and a critical issue when considering the formulation of therapeutics since multiple polymorphs may form during drug manufacturing. Low-frequency vibrational spectroscopy is sensitive to polymorphic content, and in this work, terahertz time-domain spectroscopy and low-frequency Raman spectroscopy were utilized in the study of crystalline ribavirin, a widely applicable antiviral. Characteristic spectra with numerous peaks in the sub-200 cm region were obtained of the more common polymorph of ribavirin (Form II). Read More

View Article and Full-Text PDF

Do Salient Social Norms Moderate Mortality Salience Effects? A (Challenging) Meta-Analysis of Terror Management Studies.

Pers Soc Psychol Rev 2022 Aug 11:10888683221107267. Epub 2022 Aug 11.

Aarhus University, Denmark.

Terror management theory postulates that mortality salience (MS) increases the motivation to defend one's cultural worldviews. How that motivation is expressed may depend on the social norm that is momentarily salient. Meta-analyses were conducted on studies that manipulated MS and social norm salience. Read More

View Article and Full-Text PDF

Functional traits underlying performance variations in the overwintering of the cosmopolitan invasive plant water hyacinth () under climate warming and water drawdown.

Ecol Evol 2022 Aug 4;12(8):e9181. Epub 2022 Aug 4.

State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China.

Reports of the Intergovernmental Panel on Climate Change (IPCC) indicate that temperature rise is still the general trend of the global climate in the 21st century. Invasive species may benefit from the increase in temperature, as climate can be viewed as a resource, and the increase in the available resources favors the invasibility of invasive species. This study aimed to assess the overwintering growth of the cosmopolitan invasive plant water hyacinth () at its northern boundary. Read More

View Article and Full-Text PDF

Thermodynamics of high-pressure ice phases explored with atomistic simulations.

Nat Commun 2022 Aug 10;13(1):4707. Epub 2022 Aug 10.

Institute of Science and Technology Austria, Am Campus 1, 3400, Klosterneuburg, Austria.

Most experimentally known high-pressure ice phases have a body-centred cubic (bcc) oxygen lattice. Our large-scale molecular-dynamics simulations with a machine-learning potential indicate that, amongst these bcc ice phases, ices VII, VII' and X are the same thermodynamic phase under different conditions, whereas superionic ice VII″ has a first-order phase boundary with ice VII'. Moreover, at about 300 GPa, the transformation between ice X and the Pbcm phase has a sharp structural change but no apparent activation barrier, whilst at higher pressures the barrier gradually increases. Read More

View Article and Full-Text PDF

Low-frequency Raman optical activity provides insight into the structure of chiral liquids.

Phys Chem Chem Phys 2022 Aug 10. Epub 2022 Aug 10.

Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague, Czech Republic.

Vibrational frequencies of modes involving intermolecular motions in liquids are relatively small, in the Raman scattering close to the excitation frequency, and the bands may merge into a diverging uninterpretable signal. Raman optical activity (ROA) spectral shapes in this region, however, are structured more and may better reflect the nature of the studied systems. To understand the origin of the signal and its relation to the molecules, ROA spectra of six chiral neat liquids are recorded and analyzed on the basis of molecular dynamics and density functional theory computations. Read More

View Article and Full-Text PDF

The impact of heat and inflow wind variations on vertical transport around a supertall building - The One Vanderbilt field experiment.

Sci Total Environ 2022 Aug 6:157834. Epub 2022 Aug 6.

The impact skyscrapers have on wind flow remains poorly characterized, thus affecting atmospheric dispersion predictions in dense urban centers. A new mobile observatory equipped with remote sensors controlled by a smart sampling protocol was developed to collect high-resolution (18 m, 15 s) observations throughout the atmospheric layer below 1.5 km. Read More

View Article and Full-Text PDF

Energy-Transfer-Enabled Dearomative Cycloaddition Reactions of Indoles/Pyrroles via Excited-State Aromatics.

Acc Chem Res 2022 Aug 9. Epub 2022 Aug 9.

State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.

ConspectusExploring the enormous chemical space through an expedient building-up of molecular diversity is an important goal of organic chemistry. The development of synthetic methods toward molecules with unprecedented structural motifs lays the foundation for wide applications ranging from pharmaceutical chemistry to materials science. In this regard, the dearomatization of arenes has been recognized as a unique strategy since it provides novel retrosynthetic disconnections for various spiro or fused polycyclic molecules with increased saturation and stereoisomerism. Read More

View Article and Full-Text PDF

Existence and uniqueness results for fractional Langevin equations on a star graph.

Math Biosci Eng 2022 Jul;19(9):9636-9657

School of Mathematics and Big Data, Anhui University of Science and Technology, Huainan 232001, China.

This paper discusses a class of fractional Langevin equations on a star graph with mixed boundary conditions. Using Schaefer's fixed point theorem and Banach contraction mapping principle, the existence and uniqueness of solutions are established. Finally, two examples are constructed to illustrate the application of the obtained results. Read More

View Article and Full-Text PDF

Connection between high pore-fluid pressure and frictional instability at tsunamigenic plate boundary fault of 2011 Tohoku-Oki earthquake.

Sci Rep 2022 Aug 8;12(1):12556. Epub 2022 Aug 8.

Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan.

The 2011 Tohoku-Oki earthquake (M 9.0) rupture propagated along a shallow plate boundary thrust fault (i.e. Read More

View Article and Full-Text PDF

Seasonality of Radon-222 near the surface at King Sejong Station (62°S), Antarctic Peninsula, and the role of atmospheric circulation based on observations and CAM-Chem model.

Environ Res 2022 Aug 6;214(Pt 3):113998. Epub 2022 Aug 6.

Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon 21990, South Korea. Electronic address:

We examined the seasonal cycle of radon concentration observed at King Sejong Station (KSG, 62°S), Antarctic Peninsula, during the period 2013-2016. The distribution of monthly radon concentration was found to be highly positively skewed from March through October (austral autumn to spring) due to large numbers of short-lived periods of high radon concentration. The global atmospheric chemistry model (CAM-Chem), which includes all global terrestrial sources of radon except for those in Antarctica, well reproduces the observed seasonal cycle of monthly-mean radon concentration at KSG. Read More

View Article and Full-Text PDF

Fixed and Distributed Gene Expression Time Delays in Reaction-Diffusion Systems.

Bull Math Biol 2022 Aug 7;84(9):98. Epub 2022 Aug 7.

Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Andrew Wiles Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford, OX2 6GG, United Kingdom.

Time delays, modelling the process of intracellular gene expression, have been shown to have important impacts on the dynamics of pattern formation in reaction-diffusion systems. In particular, past work has shown that such time delays can shrink the Turing space, thereby inhibiting patterns from forming across large ranges of parameters. Such delays can also increase the time taken for pattern formation even when Turing instabilities occur. Read More

View Article and Full-Text PDF

Measuring dishonest behavior: Hidden dimensions that matter.

Curr Opin Psychol 2022 Jul 1;47:101408. Epub 2022 Jul 1.

Kinneret Teodorescu, Faculty of Industrial Engineering and Management, Technion, Israel Institute of Technology, Haifa, Israel.

Dishonesty has become a trending topic in the behavioral sciences. To quantify dishonest behavior, various experimental paradigms have been introduced. These experimental paradigms differ along several methodological dimensions. Read More

View Article and Full-Text PDF