bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Interactions of Some Alkali and Alkali Earth Metallic Chlorides on Guaiacol Oxidation by Peroxidase from Watermelon Rind
Authors: O.M Iniaghe, , A.A Ohilebo
Published: August 2024

Aim: This study evaluated Interactions of some alkali and alkali earth metallic chlorides on guaiacol oxidation by peroxidase from watermelon rind.
Study Design:  In vitro enzyme assay.
Place and Duration of Study: Department of Biochemistry, Faculty of Life Sciences, Ambrose Alli University, Ekpoma, Edo State, Nigeria between September  2023 to November  2023.
Methodology: The kinetics of the oxidation of Guaiacol by the crude peroxidase from the rind of watermelon in the presence of varying concentrations of the chloride salts of Na, K, Mg and Ca was determined spectrophotometrically by monitoring the oxidation of Guaiacol to produce a brown tetraguaiacol monitored at a wavelength of 470nm.  The various salt concentrations were varied between 0.5 mM and 3 mM.  Each of the reaction mixtures used in the kinetic study comprised;  2.3 mL of 0.6 M sodium acetate buffer (pH 5.4), 0.2 mL of 0.02 mM Guaiacol, 0.1 mL of crude extract, 0.2 mL of varying concentration chloride salt, 0.2 mL of 2 mM of H2O2 added last to start the reaction. The final concentration of H2O2 in the 3 mL assay was 0.13 mM. The total volume of the reaction mixture was 3 mL. The absorbance was read every 2 seconds for one minute after adding hydrogen peroxide using a stop-clock. The control had no metal ion but replaced with distilled water
Results: Results showed that within a salt concentration range of 0.5mM to 3Mm, chlorides of  Na, K and Mg  activated the peroxidase from the rind of watermelon while CaCl2 reduced the activity in a concentration dependent manner. The optimal salt concentration of these cation activators was 0.5 mM.
Conclusion: These findings are of great importance to industries in understanding the mechanism of action of peroxidase from the rind of watermelon, especially as the search for cheap and alternative sources of peroxidases continues.
Impact of Long Term Tillage and Soil Moisture Regime on the Sulphur, Organic Carbon, DOC, MBC and MBN of Soil under Mung Bean-Wheat and Sorghum-Wheat Cropping System
Authors: Kochar Deepak , Kumar Rohtas
Published: August 2024

The field experiment entitled was conducted during 2021-22 on an on-going long term experiment which was started since 2006-07 at Soil Research Farm, Department of Soil Science, CCS HAU, Hisar. The field experiment consisted of three tillage treatments i.e. CT-CT (Conventional tillage in both kharif and rabi season), ZT-CT (Zero tillage in kharif and conventional tillage in rabi) and ZT-ZT (Zero tillage in both kharif and rabi season). The experiment also consisted of two cropping systems MW and SW (Mung bean-wheat and sorghum-wheat) and three soil moisture regimes (IW/CPE= 0.60, 0.75 and 0.90) with three replications. The results of the experiments revealed that the sulphur, organic carbon, DOC, MBC and MBN content of the soil were higher under MW than SW cropping system. The highest mean value of sulphur, organic carbon, DOC, MBC and MBN was reported under ZT-ZT followed by ZT-CT and the lowest mean value was under CT-CT under both cropping systems. Similarly, the soil moisture regime M0.90 reported the highest mean value of available sulphur, organic carbon, DOC, MBC and MBN content followed by M0.75 whereas the lowest mean value was under M0.60 under both the cropping system.
Completion of Weakly Sign Symmetric PO-Matrix Problem for 5 × 5 Matrices Specifying Digraphs of Order 5 with UP to 5 Arcs
Authors: Marro Joseph , Mutembei Josephine , Njagi Loyford
Published: August 2024

An n × n matrix is a weakly sign symmetric matrix if the off-diagonal elements have the property that if the entry in row i and column j is non-zero, then the entry in row j and column i must have same sign or zero. A digraph D has a Wss Po -matrix completion if every partial weakly sign symmetric Po -matrix that describes D can be extended to a complete weakly sign symmetric Po -matrix. This paper investigates the problem of completing weakly sign symmetric Po -matrices. It demonstrates that partial matrices representing all directed graphs of order 5 with edge strengths from 0 to 5 can indeed be completed to a weakly sign symmetric Po -matrix. Moreover, we established digraph characteristics that the partial Wss Po- matrices specifying digraphs of order 5 with up to 5 arcs which have a clique and are cyclic or acyclic have zero completion into a Wss Po- matrix. Insights gained from this class of matrix could be applied to fill gaps in data surveys, and business analytics by analysing complex relationships, allocating resources, network modelling, optimizing processes and managing risks.
Determination of Phytochemical Compositions of Leaves and Flowers of Cassia auriculate
Authors: Parani K.
Published: August 2024

The present study reveals the morphological characteristics, organoleptic and fluorescence analysis by using various chemicals and reagents to examine the presence of phytochemicals visually in powdered samples of leaves and flowers of Cassia auriculata. The qualitative analysis represents the presence of various phytochemicals viz., steroids, reducing sugars, sugars, alkaloids, phenols, flavonoids, saponins, tannins, Anthraquinones and amino acids in crude extracts (aqueous, ethanol and petroleum ether) of leaves and flowers of Cassia auriculata. The presence of minerals i.e., potassium, phosphorous, sulphur, calcium, were observed in leaves and flowers of Cassia auriculata by qualitatively. Quantitative analysis revealed   maximum amount of flavonoids in flowers of Cassia auriculata and lesser amounts of alkaloids were recorded in leaves and flowers of Cassia respectively.
Demonstration by New Finger Millet Variety ATL 1 to Improve the Productivity in Villupuram District of Tamil Nadu, India
Authors: Ganapathy S. , Gomadhi G. , Kumar M. Saran , Kumar M. Senthil
Published: August 2024

Cultivation of newly released variety has potential to increase the productivity and needs to be promoted and popularized. In this regard, the present study was carried out at farmer’s field by introducing new high yielding Finger millet variety ATL 1 to increase the productivity. The ATL 1, drought tolerant finger millet variety was released by Tamil Nadu Agricultural University during 2021. A total of fifteen, field demonstrations were conducted by using newly released finger millet variety (ATL 1) at farmer’s field organized by Krishi Vigyan Kendra, Villupuram, Tamil Nadu during Kharif 2023. The farmers cultivating variety Co 15 was used as the check variety (farmer’s practice). An average yield of 1,490 kg.ha-1 was recorded in ATL 1 demonstration plots which was 9.67 % increase over the farmers cultivating variety Co 15 (1340 kg.ha-1). The farmers were obtained additional revenue of Rs. 9,650 ha-1 from ATL 1 demonstrations. In this regard, one training on improved production technologies for millets cultivation was organized at KVK, Villupuram (Tindivanam) to improve the productivity of finger millet through demonstrations.
The Role of Biofertilizers and Phosphorus on Growth and Yield of Chickpea (Cicer arietinum L.)
Authors: Yadav Ashwani , Ranjan Satyam , Kumar Prateek , Mehera Biswarup
Published: August 2024

An agronomic investigation to study the response of Biofertilizers and Phosphorus in chickpea crop. Experiment was conducted during Rabi season of year 2023 at Crop Research Farm, Department of Agronomy. The treatments consisted of three levels of Biofertilizers (PSB- 20, Rhizobium-20, and Rhizobium+PSB-20g/kg seed) and 3 levels of Phosphorus (30,45,60 kg/ha) along with RDF control (20-40-20 kg N-P-K/ha). The experiment was laid out in Randomized Block Design with three replications. Application of Phosphorus 60 kg/ha+ Rhizobium 20g/kg seed + PSB 20g/kg seed (Treatment 9) was recorded highest growth attribute (plant height, maximum plant dry weight, no. of nodules, CGR and RGR) and yield attribute (pods per plant, seeds per pod and test weight) along with produced higher seed yield (20.71 kg/ha), straw yield (4147.13 kg/ha) and harvest index (28.98%).
Role of Mating Receptivity Peptides in Helicoverpa armigera: Molecular and Evolutionary Perspectives
Authors: Thyloor Rama , Bhogegowda Kiran Kumar Halagur , Saraswathi Saraswathi , Manjulakumari Doddamane
Published: August 2024

Previous studies have implicated the role of peptides/proteins in male accessory glands (MAGs), responsible for the induction of behavioral and reproductive changes in Helicoverpa armigera females. Our and several other studies have seen the MAG showed post-mating behaviors such as accelerated unreceptivity to re-mating and other post-mating traits. We have reported several peptides responsible for reduced mating receptivity, including a putative 4.9 kDa, a novel peptide with various functions in female post-copulatory reproductive behavior (PMR). In this study, we report a detailed analysis of the proteins from a biochemical, physiological, molecular and evolutionary perspective. 5 major classes of multigene family proteins were detected after protein database searches. All proteins were found to bind nucleic acids, possess signal peptides, and undergo posttranslational modification by seminal fluid proteins (SFPs). The Porphobilinogen synthetase protein (PBGS) was unique to the lepidopteran order. Our molecular studies support the observation that the molecular weight of MAG proteins varies significantly across species, suggesting the existence of different target sites or faster evolution of SFP. MAG proteins not only ensure male reproductive fitness by constantly evolving under postcopulatory sexual selection (PCSS), but also maintain species-specific barriers to fertilization thus potentially contribute to the formation of new species and mediate reproductive conflicts between the sexes.
Economics of Tomato (Solanum lycopersicum L.) Production under Plastic Tunnel Technology in Peri-urban Areas of Kathmandu, Nepal
Authors: Bhandari Jal Devi , Adhikari Shiva Prasad
Published: August 2024

Fresh vegetables, whether seasonal or off-seasonal, are seen as valuable crops in Nepal, and there is a strong push for their commercial production. Among them, tomato cultivation is widespread, with off-season tomato farming gaining traction for its greater financial returns compared to seasonal production. The main objective of this study was to examine the socio-demographic condition, economic aspects of tomato production in plastic tunnels, involving the estimation of the production function, problems and evaluation of the benefit-cost ratio. House-hold survey was conducted from May 5 to July 10, 2023, gathered data from 100 tunnel tomato growers from random sampling method from 3 wards (Chouketar Dahachok, Baad Bhanjyang and Thankot) in Chandragiri municipality, Kathmandu. We included 100 tunnel tomato growers (58 men, 42 women; age range 30-60 years). This study combined primary and secondary data sources. Primary data were collected from tomato farmers in Chandragiri municipality’s VDCs through face-to-face interviews using a pre-tested semi-structured questionnaire. Secondary data were sourced from various publications and reports, both published and unpublished. The semi-structured interviews featured open-ended questions designed to gather detailed information on socio-economic factors, demographics, resource availability, technical aspects, economic status, farm attributes, multiple regression based on the Cobb Douglas production function and farmer's views on the advantages and challenges of tomato cultivation under plastic tunnels. Results showed that price fluctuation was the major problem in the pivotal table. Most farmers (47%) were affected by blight and 49% by leaf miners. High labor cost NRs. 133794.04 increased the cost of production which was NRs 972555.9 but still farmers were benefitted with benefit cost ratio of 1.74, gross margin NRs. 2663355 and net profit NRs. 1690819.1. The research highlights the viability of tomato production in plastic tunnels, urging action on key constraints for potential growth. The use of plastic tunnel technology for tomato cultivation has become more popular among farmers in the peri-urban areas of Kathmandu Valley, providing year-round production and substantial economic benefits. This technology enables continuous growth of tomatoes, improving income during off-seasons and enhancing rural livelihoods. Although the study found tomato farming to be profitable despite high labor costs, farmers encounter numerous challenges, including natural disasters, pest infestations, disease, poor market access, and labor demands. Market-related problems such as fluctuating prices, middleman monopolies, and a lack of adequate storage and collection facilities further complicate the sale of produce, causing significant surplus losses. However, the study identifies several opportunities to improve tomato production for farmers in Chandragiri.
Theoretical Foundations and Application of Hidden Markov Models
Authors: Manjunatha B. , R. Karthik , Kiran N. R. , Naik Appaji Pundalik , G. N. Damodhara , H. Gunashekhar , S. Manju Prem , Mahendra K. R.
Published: August 2024

Hidden Markov Models (HMMs) are effective statistical techniques used to uncover underlying patterns in observable sequential data This paper provides a comprehensive overview of the theoretical foundations of HMMs, including key algorithms essential for their implementation, such as the Expectation-Maximization algorithm, the Baum-Welch algorithm, and the Viterbi algorithm. An application of HMMs to assess the likelihood of misclassification in Chronic Kidney Disease (CKD) stages is discussed, providing insights into the disease's natural progression and informing better treatment strategies.
In the case study, we conducted an analysis of the S&P 500 index dataset spanning from January 4, 2000, to September 20, 2019. This analysis, similar to Lihn's study but with an extended period, evaluates the robustness and consistency of regime identification through HMMs, offering deeper insights into market behavior over nearly two decades. HMMs identify different market regimes, revealing the underlying dynamics of bull and bear markets. The study demonstrates the superiority of a five-state HMM model in capturing market behaviors, thereby aiding in volatility forecasting. This study underscores the significance of HMMs in various domains, highlighting their ability to effectively model complex systems with hidden states. "It is a useful tool for those looking to explore and utilize HMMs across various disciplines, pushing the boundaries of statistical modeling and analysis.
Estimates of ocean wave heights and attenuation in sea ice using the SAR wave mode on Sentinel‐1A
Authors: Ardhuin Fabrice , Collard Fabrice , Chapron Bertrand , Girard‐Ardhuin Fanny , Guitton Gilles , Mouche Alexis , Stopa Justin E.
Published: March 2015

Swell evolution from the open ocean into sea ice is poorly understood, in particular the amplitude attenuation expected from scattering and dissipation. New synthetic aperture radar (SAR) data from Sentinel‐1A wave mode reveal intriguing patterns of bright oscillating lines shaped like instant noodles. We investigate cases in which the oscillations are in the azimuth direction, around a straight line in the range direction. This observation is interpreted as the distortion by the SAR processing of crests from a first swell, due to the presence of a second swell. Since deviations from a straight line should be proportional to the orbital velocity toward the satellite, swell height can be estimated, from 1.5 to 5 m in the present case. The evolution of this 13 s period swell across the ice pack is consistent with an exponential attenuation on a length scale of 200 km.
Using dynamical downscaling to examine mechanisms contributing to the intensification of Central U.S. heavy rainfall events
Authors: Harding Keith J. , Snyder Peter K.
Published: March 2015

The frequency and intensity of heavy rainfall events have increased in the Central U.S. over the last several decades, and model projections from dynamical downscaling suggest a continuation with climate change. In this study, we examine how climate change might affect mechanisms related to the development of heavy rainfall events that occur on the scale of mesoscale convective systems over the Central U.S. To accomplish these goals, we incorporate dynamical downscaled simulations of two Coupled Model Intercomparison Project phase 5 models in the Weather Research and Forecasting model that accurately simulate heavy rainfall events. For each model, a set of heavy rainfall events that match the frequency, timing, and intensity of observed events are objectively identified in historical and future simulations. We then examine multimodel composites of select atmospheric fields during these events in simulations of historical and future scenarios, enabling an identification of possible physical mechanisms that could contribute to the intensification of heavy rainfall events with climate change. Simulations show that additional moisture is transported into convective updrafts during heavy rain events in future simulations, driving stronger evaporative cooling from the entrainment of drier midtropospheric air. This results in the formation of a stronger low‐level cold pool, which enhances moisture convergence above the cold pool and increases rainfall rates during future heavy precipitation events. In addition, a warmer profile in future simulations might allow for heavier rainfall rates as a deeper atmospheric column can support additional collision‐coalescence of liquid hydrometeors.
Transient anomaly in fault zone‐trapped waves during the preparatory phase of the 6 April 2009, Mw 6.3 L'Aquila earthquake
Authors: Calderoni Giovanna , Rovelli Antonio , Di Giovambattista Rita
Published: March 2015

Fault zone‐trapped waves generated by repeating earthquakes of the 2009 L'Aquila seismic sequence show a sudden, up to 100% increase of spectral amplitudes 7 days before the main shock. The jump occurs 10 to 20 h after the ML 4.1, 30 March 2009 largest foreshock. The amplitude increase is accompanied by a loss of waveform coherence in the fault‐trapped wave train. Other geophysical and seismological parameters are known to have shown a sudden change after the 30 March foreshock. The concomitance of a consistent change in the fault zone‐trapped waves leads us to interpret our observation as due to a sudden temporal variation of the velocity contrast between the fault damage zone and hosting rocks in the focal volume. Fault zone‐trapped waves thus provide a refined time resolution for changes occurring near the rupture nucleation, with the indication of a strong variation in 1 day.
Climate‐forced changes in available energy and methane bubbling from subarctic lakes
Authors: Thornton Brett F. , Wik Martin , Crill Patrick M.
Published: March 2015

Strong correlations between seasonal energy input and methane (CH4) bubbling (ebullition) in northern lakes suggest that energy proxies might provide a constraint on the magnitude of future CH4 emissions. Ebullition is a major pathway for transporting anaerobically produced CH4 from lake sediments to the atmosphere and represents a large unquantified CH4 source. In high‐latitude, postglacial lakes during the ice‐free season, solar shortwave energy input can constrain CH4 productivity via control of sediment temperature. Utilizing long‐term climatic predictors, we calculate CH4 ebullition from three subarctic lakes in northern Sweden over the period of 1916–2079. Using observed energy trends, the seasonal average lake CH4 ebullition is predicted to increase by 80% between the 1916–1926 decade and the 2040–2079 period. Present‐day seasonal average methane ebullition is estimated to have already increased 24% since the 1916–1926 decade.
Impacts of Arctic sea ice and continental snow cover changes on atmospheric winter teleconnections
Authors: Handorf Dörthe , Jaiser Ralf , Dethloff Klaus , Rinke Annette , Cohen Judah
Published: March 2015

Extreme winters in Northern Hemisphere midlatitudes in recent years have been connected to declining Arctic sea ice and continental snow cover changes in autumn following modified planetary waves in the coupled troposphere‐stratosphere system. Through analyses of reanalysis data and model simulations with a state‐of‐the‐art atmospheric general circulation model, we investigate the mechanisms between Arctic Ocean sea ice and Northern Hemisphere land snow cover changes in autumn and atmospheric teleconnections in the following winter. The observed negative Arctic Oscillation in response to sea ice cover changes is too weakly reproduced by the model. The planetary wave train structures over the Pacific and North America regions are well simulated. The strengthening and westward shift of the Siberian high‐pressure system in response to sea ice and snow cover changes is underestimated compared to ERA‐Interim data due to deficits in the simulated changes in planetary wave propagation characteristics.
Phase transformations in an ascending adiabatic mixed‐phase cloud volume
Authors: Pinsky M. , Khain A. , Korolev A.
Published: March 2015

Regimes of liquid‐ice coexistence that may form in an adiabatic parcel ascending at constant velocity at freezing temperatures are investigated. Four zones with different microphysical structures succeeding one another along the vertical direction have been established. On the basis of a novel balance equation, analytical expressions are derived to determine the conditions specific for each of these zones. In particular, the necessary and sufficient conditions for formation of liquid water phase within an ascending parcel containing only ice particles are determined. The results are compared to findings reported in earlier studies. The role of the Wegener‐Bergeron‐Findeisen mechanism in the phase transformation is analyzed. The dependence of the phase relaxation time on height in the four zones is investigated on the basis of a novel analytical expression. The results obtained in the study can be instrumental for analysis and interpretation of observed mixed‐phase clouds.
Mathematical Transformations
Authors: McGhee Des , Picard Rainer , Trostorff Sascha , Waurick Marcus
Published: March 2015

The article conbtains sections titled:

What are Transformations and Why are They Useful?

The Fourier Series Transformations

The Abstract Fourier Series

The Classical Fourier Series

The Fourier Series Transformation in

The
z
‐Transformation

The Fourier–Laplace Transformation

Convolutions as Functions of

Functions of

Convolutions

The Fourier–Plancherel Transformation

The Fourier–Laplace Transformation and Distributions

Impulse Response

Shannon's Sampling Theorem

The Fourier‐Sine and Fourier‐Cosine Transformations

The Hartley Transformations

The Mellin Transformation

Higher‐Dimensional Transformations

Some Other Important Transformations

The Hadamard Transformation

The Hankel Transformation

The Radon Transformation
Group Theory
Authors: Gilmore Robert
Published: March 2015

The article conbtains sections titled:

Introduction

Precursors to Group Theory

Classical Geometry

Dimensional Analysis

Scaling

Dynamical Similarity

Groups: Definitions

Group Axioms

Isomorphisms and Homomorphisms

Examples of Discrete Groups

Finite Groups

Infinite Discrete Groups

Examples of Matrix Groups

Translation Groups

Heisenberg Group

Rotation Group

Lorentz Group

Lie Groups

Lie Algebras

Structure Constants

Constructing Lie Algebras by Linearization

Constructing Lie Groups by Exponentiation

Cartan Metric

Operator Realizations of Lie Algebras

Disentangling Results

Riemannian Symmetric Spaces

Applications in Classical Physics

Principle of Relativity

Making Mechanics and Electrodynamics Compatible

Gravitation

Reflections

Linear Representations

Maps to Matrices

Group Element–Matrix Element Duality

Classes and Characters

Fourier Analysis on Groups

Irreps of

Crystal Field Theory

Symmetry Groups

Dynamical Groups

Conformal Symmetry

Atomic Shell Structure

Nuclear Shell Structure

Dynamical Models

Gauge Theory

Group Theory and Special Functions

Summary of Some Properties

Relation with Lie Groups

Spherical Harmonics and

Differential and Recursion Relations

Differential Equation

Addition Theorems

Generating Functions

Glossary
Monte‐Carlo Methods
Authors: Binder Kurt
Published: March 2015

The article conbtains sections titled:

Introduction and Overview

Random‐Number Generation

General Introduction

Properties That a Random‐Number Generator (RNG) Should Have

Comments about a Few Frequently Used Generators

Simple Sampling of Probability Distributions Using Random Numbers

Numerical Estimation of Known Probability Distributions

“Importance Sampling” versus “Simple Sampling”

Monte‐Carlo as a Method of Integration

Infinite Integration Space

Random Selection of Lattice Sites

The Self‐Avoiding Walk Problem

Simple Sampling versus Biased Sampling: the Example of SAWs Continued

Survey of Applications to Simulation of Transport Processes

The “Shielding Problem”

Diffusion‐Limited Aggregation (DLA)

Monte‐Carlo Methods in Statistical Thermodynamics: Importance Sampling

The General Idea of the Metropolis Importance‐Sampling Method

Comments on the Formulation of a Monte‐Carlo Algorithm

The Dynamic Interpretation of the Monte‐Carlo Method

Monte‐Carlo Study of the Dynamics of Fluctuations Near Equilibrium and of the Approach toward Equilibrium

The Choice of Statistical Ensembles

Accuracy Problems: Finite‐Size Problems, Dynamic Correlation of Errors, Boundary Conditions

Finite‐Size–Induced Rounding and Shifting of Phase Transitions

Different Boundary Conditions: Simulation of Surfaces and Interfaces

Estimation of Statistical Errors

Sampling of Free Energies and Free Energy Barriers

Bulk Free Energies

Interfacial Free Energies

Transition Path Sampling

Quantum Monte‐Carlo Techniques

General Remarks

Path‐Integral Monte‐Carlo Methods

A Classical Application: the Momentum Distribution of Fluid He

A Few Qualitative Comments on Fermion Problems

Lattice Gauge Theory

Some Basic Ideas of Lattice Gauge Theory

A Famous Application

Selected Applications in Classical Statistical Mechanics of Condensed Matter

Metallurgy and Materials Science

Polymer Science

Surface Physics

Concluding Remarks

Glossary
Random Processes
Authors: Cruise James R. , Hryniv Ostap O. , Wade Andrew R.
Published: March 2015

The theory of stochastic processes is concerned with mathematical models of systems whose behavior is time dependent and incorporates randomness or uncertainty. The statistical structure of the system can be determined from the physical application in mind: a rich class consists ofMarkovprocesses whose future evolution depends on the past only through the present state of the system. We give a tour through some important examples of stochastic processes, primarily (but not exclusively) in a discrete setting where technicalities are minimized. Our tour is facilitated by a selection of mathematical tools of broad applicability, with a focus on generating functions and renewal ideas. We investigate in detail some illustrative specimens chosen for their relevance to applications in the physical sciences and for the mathematical ideas they elucidate.
Stochastic Differential Equations
Authors: Lord Gabriel J.
Published: March 2015

We give an introduction to Brownian motion and illustrate that although sample paths are continuous, they are nowhere differentiable. This leads to a discussion on white and colored noise. In Section 3.3, we introduce stochastic integration and look at the difference between Itô and Stratonovich integrals. We examine Itô stochastic differential equations (SDEs) in Section 3.4, giving some motivating examples, and use the Itô formula to find some exact solutions. We then consider Stratonovich SDEs and show how to convert between Itô and Stratonovich cases. We discuss numerical approximation of both Itô and Stratonovich SDEs and discuss the multilevel Monte Carlo method for weak approximation in Section 3.6. We conclude in Section 3.7 by looking at the link between SDEs and partial differential equations (PDEs) and introduce both the Fokker–Planck and backward Fokker–Planck equations.

Throughout, the aim is to develop intuition by first examining simple, one‐dimensional examples before giving more general formulations and results. Also included are some basic algorithms for numerical approximation.
Computer Algebra
Authors: Davenport James H.
Published: March 2015

The article contains sections titled:

Introduction

Computer Algebra Systems

“Elementary” Algorithms

Representation of Polynomials

Greatest Common Divisors

Square‐free Decomposition

Extended Euclidean Algorithm

Advanced Algorithms

Modular Algorithms–Integer

Modular Algorithms–Polynomial

The Challenge of Factorization

p‐adic Algorithms–Integer

p‐adic Algorithms–Polynomial

Solving Polynomial Systems

Solving One Polynomial

Real Roots

Linear Systems

Multivariate Systems

Gröbner Bases

Regular Chains

Integration

Rational Functions

More Complicated Functions

Linear Ordinary Differential Equations

Interpreting Formulae as Functions

Fundamental Theorem of Calculus Revisited

Simplification of Functions

Real Problems

Conclusion
Topics in Differential Geometry
Authors: Epstein Marcelo
Published: March 2015

This article assumes a basic knowledge of differentiable manifolds, vector fields, and differential forms (such as that provided in the article
DIFFERENTIABLE MANIFOLDS
). The first topic covered is the theory of integration of forms on oriented manifolds, whose most important result, generalizing and encompassing all the classical theorems of vector calculus, is the theorem of Stokes. The second topic is an introduction to Lie groups, namely, differentiable manifolds with a differentiablegroup structure. Important in themselves as the expression of symmetries in physical theories, Lie groups are also a necessary ingredient for the treatment of fiber bundles, which are manifolds with extra structure. Among the topics covered within this realm, principal bundles, linear connections, torsion, and curvature are particularly important in applications.
Functional Analysis
Authors: Exner Pavel
Published: March 2015

The article contains sections titled:

Banach Space and Operators on Them

Vector and Normed Spaces

Operators on Banach Spaces

Spectra of Closed Operators

Hilbert Spaces

Hilbert‐Space Geometry

Direct Sums and Tensor Products

Bounded Operators on Hilbert Spaces

Hermitean Operators

Unitary Operators

Compact Operators

Schatten Classes

Unbounded Operators

Operator Adjoint and Closure

Normal and Self‐Adjoint Operators

Tensor Products of Operators

Self‐Adjoint Extensions

Spectral Theory of Self‐Adjoint Operators

Functional Calculus

Spectral Theorem

More about Spectral Properties

Groups of Unitary Operators

Some Applications in Quantum Mechanics

Schrödinger Operators

Scattering Theory

Glossary
Numerical Analysis
Authors: Boulton Lyonell
Published: March 2015

Numerical analysis comprises a set of tools for the approximated solutions of mathematical problems. These include solutions to equations, optimization, direct computation of mathematical quantities and factorizations. The
methods
employed to determine these approximated solutions are usually implemented on electronic devices (e.g., scientific apparatus and computers). This chapter is concerned with a qualitative mathematical description of the very basic language of the theory, aimed at nonspecialists in the subject.
Partial Differential Equations
Authors: McGhee Des , Picard Rainer , Trostorff Sascha , Waurick Marcus
Published: March 2015

The article contains sections titled:

What are Partial Differential Equations?

Partial Differential Equations in with Constant Coefficients

Evolutionarity

An Outline of Distribution Theory

Integral Transformation Methods as a Solution Tool

Partial Differential Equations of Mathematical Physics

Initial‐Boundary Value Problems of Mathematical Physics

Maxwell's Equations

Viscoelastic Solids

Coupled Systems

Thermoelasticity

Piezoelectromagnetism

The Extended Maxwell System and its Uses
Highly Efficient and Broadband Upconversion of NIR Sunlight with Neodymium‐Doped Glass Ceramics
Authors: Skrzypczak Ulrich , Seifert Gerhard , Schweizer Stefan
Published: March 2015

Efficient and broadband upconversion of NIR light below the silicon bandgap is a major challenge in silicon photovoltaics. All current approaches use erbium‐based systems being well optimized for monochromatic upconversion. However, to achieve an appreciable increase of photovoltaic efficiency via photon upconversion, broadband operation of the upconversion process is required. Using our comprehensive, experimentally verified rate equation system, we show numerically that neodymium can be a highly efficient broadband upconverter of NIR photons for concentrated sunlight. When embedded into a low phonon ZBLAN‐based glass ceramic, broadband upconversion efficiencies of about 10% can be reached. Moreover, its emission spectrum shifts towards the green spectral range being the optimal range for silicon absorption.
Thiazolium‐Based Catalysts for the Etherification of Benzylic Alcohols under Solvent‐Free Conditions
Authors: Bivona Lucia Anna , Quertinmont François , Beejapur Hazi Ahmad , Giacalone Francesco , Buaki‐Sogo Mireia , Gruttadauria Michelangelo , Aprile Carmela
Published: March 2015

Thiazolium and imidazolium hybrid materials were prepared by radical reactions between a mercaptopropyl‐modified SBA‐15 mesoporous silica and bis‐vinylthiazolium or bis‐vinylimidazolium dibromide salts. These hybrid materials were characterized by several techniques and were employed in the etherification reaction of 1‐phenylethanol. Solvent‐free conditions at 160 °C under different gas phases (oxygen, air, nitrogen and argon) were used. The thiazolium‐based material displayed excellent performances. Further studies were carried out using unsupported thiazolium salts, with or without a methyl group at the C‐2 position of the thiazolium moiety. These studies allowed us to propose a reaction mechanism. The supported thiazolium‐based material was successfully used in the etherification reaction of two other benzylic alcohols and also in seven consecutive cycles. This work represents the first use of thiazolium‐based compounds as catalysts for the etherification reaction of alcohols.

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Organocatalytic Diels–Alder Reaction of 2‐Vinylindoles with Methyleneindolinones: An Efficient Approach to Functionalized Carbazolespirooxindoles
Authors: Huang Lin‐Jie , Weng Jiang , Wang Sheng , Lu Gui
Published: March 2015

An unprecedented asymmetric Diels–Alder reaction of 2‐vinylindoles with methyleneindolinones has been disclosed. Under bifunctional organocatalysis by cinchona‐derived squaramide catalyst, a series of diversely functionalized carbazolespirooxindole derivatives bearing three contiguous stereocenters are rapidly constructed under mild conditions (48–90% yields, up to >20:1 dr and 99% ee).

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Phosphaannulation of Aryl‐ and Benzylphosphonic Acids with Unactivated Alkenes via Palladium‐Catalyzed CH Activation/Oxidative Cyclization Reaction
Authors: Jeon Woo Hyung , Son Jeong‐Yu , Kim Sun‐Eung , Lee Phil Ho
Published: March 2015

An efficient phosphaannulation via palladium(II)‐catalyzed CH activation/oxidative cyclization by the 6‐endo mode is reported for the synthesis of 3‐substituted phosphaisocoumarins from the reaction of arylphosphonic acids with unactivated alkenes under aerobic conditions. Also, α,α‐disubstituted benzylphosphonic acids were phosphaannulated with unactivated alkenes, producing phosphaisochromanones having (Z)‐alkylidenyl groups via anti‐phosphoryloxypalladation by the 6‐exo mode.

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The Lithiation Reactivity and Selectivity of Differentially Branched Alkyldiphenylphosphine Oxides – A Simple and Versatile Approach to ortho‐Functionalized Arylphosphine Oxides
Authors: Mahamulkar Shraddha G. , Císařová Ivana , Jahn Ullrich
Published: March 2015

Alkyldiphenylphosphine oxides typically undergo α‐deprotonation with alkyllithium reagents. Here, the lithiation of differentially branched alkyldiphenylphosphine oxides was investigated and a diverse, but predictable reactivity was found. γ‐Branched derivatives undergo selective directed ortho‐metalation (DoM) using butyllithium and TMEDA as an additive. With decreasing degree of γ‐branching α‐lithiation becomes predominant. The ortho‐phosphinoyllithium intermediates are subject to functionalization and CC bond forming reactions, thus providing a convenient approach to new phosphine oxides and phosphine‐borane complexes, which have a good potential for an approach to new ligands for catalysis.

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Enantioselective Construction of Cyclic Indolyl α‐Amino Esters via a Friedel–Crafts Alkylation Reaction
Authors: Wu Liang , Liu Ren‐Rong , Zhang Guoqi , Wang Dan‐Jie , Wu Hao , Gao Jianrong , Jia Yi‐Xia
Published: March 2015

An enantioselective Friedel–Crafts alkylation reaction of indoles with cyclic N‐sulfonyl ketimino esters was developed. Under the optimized conditions using a chiral copper(II) triflate‐bisoxazoline complex as the catalyst, a range of N‐sulfonyl ketimino ester derivatives and indoles reacted smoothly to afford indole‐containing chiral cyclic α‐amino esters bearing tetrasubstituted α‐stereogenic centers [3‐ethoxycarbonyl‐3‐(3‐indolyl)‐2,3‐dihydrobenzo[d]isothiazole 1,1‐dioxides] in excellent yields and with high enantioselectivities (up to 99% ee). Pyrrole and N,N‐dimethylaniline were also investigated as aromatic substrates to afford the corresponding products with good results. An asymmetric induction model was then proposed on the basis of the observed absolute configuration of the product 3‐ethoxycarbonyl‐3‐(5‐bromo‐3‐indolyl)‐2,3‐dihydrobenzo[d]isothiazole 1,1‐dioxide. Synthetic transformations to convert the products into cyclic chiral N‐sulfonamido alcohols and the deprotection of the sulfonamides were performed. This study provides an efficient approach to chiral α‐tetrasubstituted indolic α‐amino acids as potential building blocks for peptides and biologically active molecules.

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N‐Heterocyclic Carbene‐Catalyzed Umpolung Formal [3+3] Cycloaddition of Enals with Isatogens: Access to Fused Indolin‐3‐ones with a Tetrasubstituted Carbon Stereocenter
Authors: Xu Junyu , Hu Shihe , Lu Yingyan , Dong Ying , Tang Weifang , Lu Tao , Du Ding
Published: March 2015

A novel synthetic method to access fused indolin‐3‐ones with a tetrasubstituted carbon stereocenter has been developed via NHC‐catalyzed umpolung formal [3+3] cycloaddtion of enals with isatogens. This methodology could be also applied for the quick construction of the 6‐5‐5 tricyclic pyrrolo[1,2‐a]indole skeleton which is frequently found as a core structure of many indole alkaloids.

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Supported Catalysis in Continuous‐Flow Microreactors
Authors: Munirathinam Rajesh , Huskens Jurriaan , Verboom Willem
Published: March 2015

This review surveys the recent developments to perform heterogeneous catalysis in continuous‐flow microreactors. Three different types, namely, (i) packed‐bed, (ii) monolithic, and (iii) wall‐coated approaches are discussed to implement various kinds of catalysts in a microreactor. In addition, the applications of these supported catalysts to perform a variety of organic reactions are described. Furthermore, advantages of catalytic microreactors over classical batch reactors on one or more aspects of the reaction, such as rate, conversion, selectivity, and enantioselectivity are presented.

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Formal N‐Acylation Reaction of Azaaromatics with Acylzirconocene Chloride Complexes and 1,1,1,3,3,3‐Hexafluoro‐2‐propanol
Authors: Saito Akio , Uematsu Yuki , Sudo Kohei , Hanzawa Yuji
Published: March 2015

In the presence of 1,1,1,3,3,3‐hexafluoro‐2‐propanol (1,1,1,3,3,3‐hexafluoroisopropyl alcohol, HFIP), isoquinolines react with acylzirconocene chlorides to give N‐acyl adducts with incorporation of a proton at the C‐1 position. The present procedure could be applied to the reaction of quinolines. These reactions provide us with an alternative method for the Reissert‐type reduction reactions of azaaromatics with N‐acylating reagents and reducing reagents.

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Metal‐Free [2+2+1] Annulation of Alkynes, Nitriles and Nitrogen Atoms from Iminoiodanes for Synthesis of Highly Substituted Imidazoles
Authors: Saito Akio , Kambara Yui , Yagyu Takuma , Noguchi Keiichi , Yoshimura Akira , Zhdankin Viktor V.
Published: March 2015

Boron trifluoride nitrile complexes promote oxidative [2+2+1] annulations of alkynes, nitriles and N‐atoms from iminoiodanes to give the corresponding 2,4‐disubstituted and 2,4,5‐trisubstituted N‐tosylimidazoles in moderate to good yields with high regioselectivities.

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The neurocognitive impact of Fabry disease on pediatric patients
Authors: Bugescu Nicolle , Alioto Andrea , Segal Summer , Cordova Matthew , Packman Wendy
Published: March 2015

Fabry disease (FD) is an X‐linked lysosomal storage disorder that results in progressive multisystemic organ complications. Several studies have examined neurocognitive impairments in adults; however, there is a paucity of research examining neurocognitive functioning in children with FD. This is the first exploratory study to examine the neurocognitive functioning of pediatric patients with FD and to evaluate the effects of enzyme replacement therapy (ERT) on neurocognitive functioning within this population. Families attending a national conference with at least one child with FD and one parent affected by FD comprised the sample (n = 48; 24 pediatric patients, 24 parents). Pediatric participants (10 males, 14 females) between the ages of 6 and 18 years and their parent(s) were involved in the study. Data from a demographic questionnaire and two neurocognitive self‐report and parent‐report measures were analyzed. Parent reports of neurocognitive functioning were also compared to a sample of children with and without head injury and to a sample of children who had undergone liver transplant (LT). Children with FD had poorer cognitive and executive functioning than healthy peers, and were comparable to children with head injury and LT. In addition, children using ERT had higher scores on measures of overall cognitive functioning, as well as fewer problems with attention/working memory and executive functioning. Results of this study suggest that children with FD may exhibit poorer cognitive and executive functioning relative to healthy peers. The use of ERT may mitigate the negative impact of FD on neurocognitive functioning in pediatric patients. © 2015 Wiley Periodicals, Inc.
Synthese von Kohlenstoffnanostrukturen durch ionothermale Karbonisierung von gewöhnlichen Lösungsmitteln und Lösungen
Authors: Chang Yuanqin , Antonietti Markus , Fellinger Tim‐Patrick
Published: March 2015

Eine Kombination aus Ionothermalsynthese und Heißinjektionstechnik führte zu aus Lösungsmitteln erzeugten neuartigen Kohlenstoffnanostrukturen. Bei kontrollierter Zugabe von gewöhnlichen Lösungsmitteln zu heißer Zinkchloridschmelze entstanden sphärische, schichtartige oder verzweigt‐nanofaserige Nanopartikel mit erstaunlich hoher Kohlenstoffeffizienz. Die Verwendung Heteroatom‐haltiger Lösungsmittel hatte die Herstellung von Kohlen mit Dotierungsgraden von bis zu 14 Gew.‐% Stickstoff und 13 Gew.‐% Schwefel zur Folge. Hohe Oberflächen und große Porenvolumina der Lösungsmittelkohlen von >1666 m2 g−1 und 2.80 cm3 g−1 sowie CO2‐Absorptionskapazitäten von 4.13 mmol g−1 bei 273 K und 1 bar konnten erhalten werden. Die neuartige Methode ließ sich nicht nur auf reine Kohlen anwenden, sondern wurde zudem auf die Herstellung von Nanokompositmaterialien aus Kohlenstoff und anorganischen Verbindungen ausgeweitet. ZnS@C, Ni@C und Co@C wurden erfolgreich mit der “kinderleichten” Methode hergestellt. Das Ni@C‐Nanokomposit eignet sich zur elektrokatalytischen Wasserspaltung, vergleichbar zu kommerziellen Edelmetallkatalysatoren.
Polymer crystallization rate challenges: The art of chemistry and processing
Authors: Andjelić Saša , Scogna Robert C.
Published: March 2015

The intention of this study is to discuss scientific advances toward one very important challenge in the polymer processing industry: How does one increase the crystallization rate of slow‐to‐crystallize polymeric materials, thereby facilitating processing and enabling peak product performance? In the medical device field, where both government‐controlled regulatory entities and medical professionals closely scrutinize the biocompatibility of added crystallization rate enhancers, achieving these twin goals has always been challenging. Herein, we present a review of various chemical and physical approaches used to tune the crystallization rate of semicrystalline polymers, with a strong emphasis on two novel approaches recently discovered and developed in our laboratories. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 42066.
Synthesis of well‐defined amphiphilic block copolymers via AGET ATRP used for hydrophilic modification of PVDF membrane
Authors: Sun Haixiang , Wang Tiantian , Zhou Yingying , Li Peng , Kong Ying
Published: March 2015

A well‐defined amphiphilic block copolymer consisting of a hydrophobic block poly(methyl methacrylate) (PMMA) and a hydrophilic block poly[N,N–2‐(dimethylamino) ethyl methacrylate] (PDMAEMA) was synthesized by activator generated by the electron transfer for atom transfer radical polymerization method (AGET ATRP). Kinetics study revealed a linear increase in the graph concentration of PMMA‐b‐PDMAEMA with the reaction time, indicating that the polymer chain growth was consistent with a controlled process. The gel permeation chromatography results indicated that the block copolymer had a narrow molecular weight distribution (Mw/Mn = 1.42) under the optimal reaction conditions. Then, poly(vinylidene fluoride) (PVDF)/PMMA‐b‐PDMAEMA blend membranes were prepared via the standard immersion precipitation phase inversion process, using the block copolymer as additive to improve the hydrophilicity of the PVDF membrane. The presence and dispersion of PMMA‐b‐PDMAEMA clearly affected the morphology and improved the hydrophilicity of the as‐synthesized blend membranes as compared to the pristine PVDF membranes. By incorporating 15 wt % of the block copolymer, the water contact angle of the resulting blend membranes decreased from pure PVDF membrane 98° to 76°. The blend membranes showed good stability in the 20 d pure‐water experiment. The bovine serum albumin (BSA) absorption experiment revealed a substantial antifouling property of the blend membranes in comparison with the pristine PVDF membrane. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42080.