An ultracentrifuge is a centrifuge optimized for spinning a rotor at very high speeds, capable of generating acceleration as high as 1 000 000 g. There are two kinds of ultracentrifuges, the preparative and the analytical ultracentrifuge. Both classes of instruments find important uses in molecular biology, biochemistry, and polymer science.
In mathematics, the term linear function refers to two distinct but related notions:
High-performance liquid chromatography (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify specific components in mixtures. The mixtures can originate from food, chemicals, pharmaceuticals, biological, environmental and agriculture, etc., which have been dissolved into liquid solutions.
SPSS Statistics is a statistical software suite developed by IBM for data management, advanced analytics, multivariate analysis, business intelligence, and criminal investigation. Long produced by SPSS Inc., it was acquired by IBM in 2009. Versions of the software released since 2015 have the brand name IBM SPSS Statistics.
Centrifugation is a mechanical process which involves the use of the centrifugal force to separate particles from a solution according to their size, shape, density, medium viscosity and rotor speed. The denser components of the mixture migrate away from the axis of the centrifuge, while the less dense components of the mixture migrate towards the axis. Chemists and biologists may increase the effective gravitational force of the test tube so that the precipitate (pellet) will travel quickly and fully to the bottom of the tube. The remaining liquid that lies above the precipitate is called a supernatant or supernate.
Biovail Corporation was a Canadian pharmaceutical company, operating internationally in all aspects of pharmaceutical products. Its major production facility was located in Steinbach, Manitoba. It merged with Valeant Pharmaceuticals International in 2010.
Protein purification is a series of processes intended to isolate one or a few proteins from a complex mixture, usually cells, tissues or whole organisms. Protein purification is vital for the specification of the function, structure and interactions of the protein of interest. The purification process may separate the protein and non-protein parts of the mixture, and finally separate the desired protein from all other proteins. Ideally, to study a protein of interest, it must be separated from other components of the cell so that contaminants will not interfere in the examination of the protein of interest's structure and function. Separation of one protein from all others is typically the most laborious aspect of protein purification. Separation steps usually exploit differences in protein size, physico-chemical properties, binding affinity and biological activity. The pure result may be termed protein isolate.
Understeer and oversteer are vehicle dynamics terms used to describe the sensitivity of the vehicle to changes in steering angle associated with changes in lateral acceleration. This sensitivity is defined for a level road for a given steady state operating condition by the Society of Automotive Engineers (SAE) in document J670 and by the International Organization for Standardization (ISO) in document 8855. Whether the vehicle is understeer or oversteer depends on the rate of change of the understeer angle. The Understeer Angle is the amount of additional steering that must be added in any given steady-state maneuver beyond the Ackermann steer angle. The Ackermann Steer Angle is the steer angle at which the vehicle would travel about a curve when there is no lateral acceleration required.
The analytic element method (AEM) is a numerical method used for the solution of partial differential equations. It was initially developed by O.D.L. Strack at the University of Minnesota. It is similar in nature to the boundary element method (BEM), as it does not rely upon the discretization of volumes or areas in the modeled system; only internal and external boundaries are discretized. One of the primary distinctions between AEM and BEMs is that the boundary integrals are calculated analytically. Although originally developed to model groundwater flow, AEM has subsequently been applied to other fields of study including studies of heat flow and conduction, periodic waves, and deformation by force.
The AutoAnalyzer is an automated analyzer using a flow technique called continuous flow analysis (CFA), or more correctly segmented flow analysis (SFA) first made by the Technicon Corporation. The instrument was invented in 1957 by Leonard Skeggs, PhD and commercialized by Jack Whitehead's Technicon Corporation. The first applications were for clinical analysis, but methods for industrial and environmental analysis soon followed. The design is based on segmenting a continuously flowing stream with air bubbles.
PQS is a general purpose quantum chemistry program. Its roots go back to the first ab initio gradient program developed in Professor Peter Pulay's group but now it is developed and distributed commercially by Parallel Quantum Solutions. There is a reduction in cost for academic users and a site license. Its strong points are geometry optimization, NMR chemical shift calculations, and large MP2 calculations, and high parallel efficiency on computing clusters. It includes many other capabilities including Density functional theory, the semiempirical methods, MINDO/3, MNDO, AM1 and PM3, Molecular mechanics using the SYBYL 5.0 Force Field, the quantum mechanics/molecular mechanics mixed method using the ONIOM method, natural bond orbital (NBO) analysis and COSMO solvation models. Recently, a highly efficient parallel CCSD(T) code for closed shell systems has been developed. This code includes many other post Hartree–Fock methods: MP2, MP3, MP4, CISD, CEPA, QCISD and so on.
The COLUMBUS PROGRAMS are a computational chemistry software suite for calculating ab initio molecular electronic structures, designed as a collection of individual programs communicating through files. The programs focus on extended multi-reference calculations of atomic and molecular ground and excited states. In addition to standard classes of reference wave functions such as CAS and RAS, calculations can be performed with selected configurations. Some features employ the atomic orbital integrals and gradient routines from the Dalton as well as MOLCAS program suites. COLUMBUS is distributed open-source under the LGPL license.
In fluid dynamics, flow separation or boundary layer separation is the detachment of a boundary layer from a surface into a wake.
IQVIA, formerly Quintiles and IMS Health, Inc., is an American Fortune 500 and S&P 500 multinational company serving the combined industries of health information technology and clinical research. IQVIA is a provider of biopharmaceutical development, professional consulting and commercial outsourcing services, focused primarily on Phase I-IV clinical trials and associated laboratory and analytical services, including investment strategy and management consulting services. It has a network of more than 88,000 employees in more than 100 countries and a market capitalization of US$49 billion as of August 2021. As of 2023, IQVIA was reported to be one of the world's largest contract research organizations (CRO).
IHS Markit Ltd was an information services provider that completed a merger with S&P Global in 2022. Headquartered in London, it was formed in 2016 with the merger of IHS Inc. and Markit Ltd.
Verisk Analytics, Inc. is an American multinational data analytics and risk assessment firm based in Jersey City, New Jersey, with customers in insurance, natural resources, financial services, government, and risk management sectors. The company uses proprietary data sets and industry expertise to provide predictive analytics and decision support consultations in areas including fraud prevention, actuarial science, insurance coverage, fire protection, catastrophe and weather risk, and data management.
Moody's, previously known as Moody's Analytics, is a subsidiary of Moody's Corporation established in 2007 to focus on non-rating activities, separate from Moody's Investors Service. It provides economic research regarding risk, performance and financial modeling, as well as consulting, training and software services. Moody's is composed of divisions such as Moody's KMV, Moody's Economy.com, Moody's Wall Street Analytics, the Institute of Risk Standards and Qualifications, and Canadian Securities Institute Global Education Inc.
OpenNN is a software library written in the C++ programming language which implements neural networks, a main area of deep learning research. The library is open-source, licensed under the GNU Lesser General Public License.
Google JAX is a machine learning framework for transforming numerical functions, to be used in Python. It is described as bringing together a modified version of autograd and TensorFlow's XLA. It is designed to follow the structure and workflow of NumPy as closely as possible and works with various existing frameworks such as TensorFlow and PyTorch. The primary functions of JAX are:
- grad: automatic differentiation
- jit: compilation
- vmap: auto-vectorization
- pmap: SPMD programming
