Huge Number Of Cells Research Articles

The genome of the pygmy right whale illuminates the evolution of rorquals

BackgroundBaleen whales are a clade of gigantic and highly specialized marine mammals. Their genomes have been used to investigate their complex evolutionary history and to decipher the molecular mechanisms that allowed them to reach these dimensions. However, many unanswered questions remain, especially about the early radiation of rorquals and how cancer resistance interplays with their huge number of cells. The pygmy right whale is the smallest and most elusive among the baleen whales. It reaches only a fraction of the body length compared to its relatives and it is the only living member of an otherwise extinct family. This placement makes the pygmy right whale genome an interesting target to update the complex phylogenetic past of baleen whales, because it splits up an otherwise long branch that leads to the radiation of rorquals. Apart from that, genomic data of this species might help to investigate cancer resistance in large whales, since these mechanisms are not as important for the pygmy right whale as in other giant rorquals and right whales.ResultsHere, we present a first de novo genome of the species and test its potential in phylogenomics and cancer research. To do so, we constructed a multi-species coalescent tree from fragments of a whole-genome alignment and quantified the amount of introgression in the early evolution of rorquals. Furthermore, a genome-wide comparison of selection rates between large and small-bodied baleen whales revealed a small set of conserved candidate genes with potential connections to cancer resistance.ConclusionsOur results suggest that the evolution of rorquals is best described as a hard polytomy with a rapid radiation and high levels of introgression. The lack of shared positive selected genes between different large-bodied whale species supports a previously proposed convergent evolution of gigantism and hence cancer resistance in baleen whales.

Design of Energy Management System Base on lithium-ion Battery

In today's world, green energy is becoming increasingly important. Due to air pollution, electric vehicles are currently the greatest option for the environment, personal and public transportation. Electric vehicles need batteries, which might be hazardous if they are not used in a safe atmosphere. The purpose of this work is to develop a battery management system (BMS) prototype that can track the voltages, currents, and cell balancing of each cell in a battery pack, as well as the temperature of the pack. The batteries in electric vehicles must always be kept under control within their operational safety area (SOA). To achieve the desired voltage and capacity, multiple battery cells are joined. A huge number of cells are necessary to provide the high voltage and capacity required for electric vehicles. This paper developed methods for monitoring each battery cell's functionality and Algorithms for detecting bad cells for replacement in the battery pack and displaying those cells condition on the monitor whether they are good or bad to notify the users, the current conditions of each cell for the user's next line of action. The experiment was carried out using STM32 microcontrollers.

A simple method for isolation of rest of trypsinized stem cells with magnetic beads

Till now, there is no laboratory in the world, which makes thoughts that there may be still stem cells remaining in the flasks after the trypsin treatment. The user checks the presence of stem cells during trypsinization with the microscope whether the whole population of stem cells has been collected. Magnetic beads are being used around the world to isolate different kinds of cells like CD4, CD8, CD34, and other cells. One of the advantages of magnetic isolation is that they can be used to isolate cells from solutions containing even a low number of targeted cells. We conducted the experiments to see whether all remaining MSC can be obtained from a trypsin-treated flask with magnetic beads isolation.
 During the magnetic isolation with CD90 specific Magnetic beads, it was found under the microscope that there are huge numbers of cells being attached to beads. The results indicate that there are still a huge number of rest cells in the trypsinized flask but most of the users think that they have isolated all cells, which is not true and they are throwing away valuable stem cells. The magnetic beads can be used to isolate the rest of MSC because for many applications, there is a need of the largest number of stem cells for conducting studies like flow cytometry, molecular testing along with pre-clinical and clinical studies.

Managing pot-lines containing low amperage Hall-Héroult cell through operational and technical excellence during blackout and load reductions

Aluminium is produced in Hall-Héroult smelting cell which is a highly energy-intensive process. Most of the integrated Aluminium production plant contains a large number of Hall-Héroult cells fixed in series called Pot-line. It is critical to operating a Pot-line on low current than the design range for much extended period. A load reduction event or blackout in a low amperage Pot-line is risky. The result can be as bad as freezing the entire Pot-line. Hindalco is well-known for being a pioneer in the field of Aluminium Production. Hindalco Industries Limited operates Aluminium smelter with many Pot-lines with a huge number of cells. In last few years at Renukoot Smelter, two major Blackouts happened. The Power plant to supply current to Smelter developed breakdown the amperage was dropped. It took many days to get the normal load. It was a big challenge to run the Pot-line at lower amperage but all the pots were managed properly by good strategy and proper planning. Due to the swift, proactive and skilful steps taken during the power outage in the Pot room, pot loss and the critical parameters could be controlled and the Pot-line was back to standard operation in only a few days. The technology of Renukoot smelter is based on low amperage Hall-Héroult cells but today also it sustains because of the skilled manpower and proper planning. This paper describes the effects of Blackout & Load Reduction on Pot-lines. It also describes our best practices and the measures that we took to run the low amperage pots at reduced amperages or during the blackout in a smooth way until the load was increased to the normal value.

A Parallel CE-LOD-FDTD Model for Instrument Landing System Signal Disturbance Analyzing

Before a new airport runway is built, the electromagnetic compatibility of the instrument landing system (ILS) must be fully taken into consideration. The electromagnetic compatibility requirements for airports are becoming more and more complex, so rather than using traditional ray-tracing (RT) simulation models, a more accurate approach such as the finite-difference time domain (FDTD) is needed. The application of FDTD to ILS signal modeling suffers from an intensively high computation burden. The computation burden is owing to: 1) the FDTD has to loop a large number of time steps and 2) for every step, a huge number of cells has to be updated. This paper solves the above-mentioned issues by twofold. First, this model allows a large Courant–Friedrich–Levy number for the FDTD to reduce the total time step. This is achieved by combining the locally one-dimension (LOD) FDTD and the complex-envelope (CE) technique. The combination of CE, LOD, and FDTD (CE-LOD-FDTD) makes the model update with larger time step and retain the same level of accuracy. Second, we propose a set of novel GPU-based acceleration algorithms to update the field in parallel for reducing the computation time. By comparing the measurement results, it is shown that the FDTD model is more accurate than the traditional RT-based method. Our GPU-based CE-LOD-FDTD model is 22 times faster than the conventional parallel FDTD model in a multicore machine.

Mesh independency study for an elementary perforated panel part of an air solar collector

In order to achieve the numerical model of a transpired solar collector (TSC) with integrated phase changing materials (PCM) it is mandatory to study the impact of the orifice geometry on the entire system. The numerical simulation of the entire solar collector absorber metal plate (1000x2000mm and 5000 orifices) is not feasible thus resulting a huge number of cells for the numerical grid for which we will need very high computational resources and a very large amount of time to be solved. By taking these aspects into account we decided to simulate only four equivalent orifices and then to transpose the results to the actual case for further studies. The present paper aims to analyse the mesh independency study for an elementary perforated panel with four equivalent lobed orifices which is part of a real case TSC. This analysis represents one of the most important stages within the construction of the TSC numerical model and doesn't need an experimental validation. The study was conducted in Ansys Fluent CFD software and the results were processed directly by using Tecplot software. Six different meshes were analysed (from 0.2 to 7.3 million cells), boundary conditions were imposed, and k-ε RNG turbulence model was used according to the literature. After comparing velocity and temperature fields in longitudinal and transverse planes we concluded that from 5.3 million cells the solution is independent of the meshing quality.

New Frontiers of Metallomics: Elemental and Species-Specific Analysis and Imaging of Single Cells.

Single cells represent the basic building units of life, and thus their study is one the most important areas of research. However, classical analysis of biological cells eludes the investigation of cell-to-cell differences to obtain information about the intracellular distribution since it only provides information by averaging over a huge number of cells. For this reason, chemical analysis of single cells is an expanding area of research nowadays. In this context, metallomics research is going down to the single-cell level, where high-resolution high-sensitive analytical techniques are required. In this chapter, we present the latest developments and applications in the fields of single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS), mass cytometry, laser ablation (LA)-ICP-MS, nanoscale secondary ion mass spectrometry (nanoSIMS), and synchrotron X-ray fluorescence microscopy (SXRF) for single-cell analysis. Moreover, the capabilities and limitations of the current analytical techniques to unravel single-cell metabolomics as well as future perspectives in this field will be discussed.

Implicit 2D surface flow models performance assessment: Shallow Water Equations vs. Zero-Inertia Model

Zero-Inertia (ZI) models are used in overland flow simulation due to their mathematical simplicity, compared to more complex formulations such as Shallow Water (SW) models. The main hypothesis in ZI models is that the flow is driven by water surface and friction gradients, neglecting local accelerations. On the other hand, SW models are a complete dynamical formulation that provide more information at the cost of a higher level of complexity. In realistic problems, the usually huge number of cells required to ensure accurate spatial representation implies a large amount of computing effort and time. This is particularly true in 2D models. Hence, there is an interest in developing efficient numerical methods. In general terms, numerical schemes used to solve time dependent problems can be classified in two groups, attending to the time evaluation of the unknowns: explicit and implicit methods. Explicit schemes offer the possibility to update the solution at every cell from the known values but are restricted by numerical stability reasons. This can lead to very slow simulations in case of using fine meshes. Implicit schemes avoid this restriction at the cost of generating a system of as many equations as computational cells multiplied by the number of variables to solve. In this work, an implicit finite volume numerical scheme has been used to solve the 2D equations in both ZI and SW models. The scheme is formulated so that both quadrilateral and triangular meshes can be used. A conservative linearization is done for the flux terms, leading to a non-structured matrix for unstructured meshes thus requiring iterative methods for solving the system. A comparison between 2D SW and 2D ZI is done in terms of performance, efficiency and mesh requirements, in which both models benefit of an implicit temporal discretization in steady and nearly-steady situations.

A Risk Assessment Methodology to Prioritise Risks in Large, Stationary Li-Ion Battery Systems

Performing a risk analysis is the basis in all engineered products. No specific methodology exists for stationary batteries. Indications on the needed risk assessment may be derived from standards that cover large stationary Li-ion battery storage systems in their scope [1]. However, they hardly go further than referring to the general risk assessment techniques with as examples Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA). Despite this lack of specific guidance, a risk assessment for large battery systems has their uniqueness due to their structure. There are many levels between battery cells and the complete system. Moreover, a huge number of cells are used that must be correctly dealt with in the assessment. In the scientific literature only a few papers are dedicated to risk assessment on batteries. This contribution sets up a complete framework of methodologies and protocols for safety testing of stationary Li-ion batteries for large-scale grid-connected applications. The risk assessment is based on the well-known Failure Mode Effects Analysis (FMEA) method. In a first step, a generic hierarchical system diagram of a stationary battery is developed to be used as the system under study in the FMEA. To improve the completeness and the objectivity of the analysis, improvements to the FMEA methodology are proposed and used. The main goal of these improvements is to limit the dependency on expert judgement and inspiration and to improve the prioritization of risks without adding unnecessary complexity. A core issue is that the method of calculating the Risk Priority Number (RPN) is not sufficient fo large battery systems. This problem was also detected by [2]. The RPN does not take suitable care of the numbers of cells, modules, etc. and has no aggregation per level. Risks that are mitigated on several system levels have to be aggregated in an advanced RPN methodology. This leads to a thorough risk assessment, in which it is easy and meaningful to select the most prominent project risks. This contribution is an outcome of the European FP7 project Stallion. The project has set up safety tests beyond state of the art for stationary Li-ion battery systems. It also resulted in a handbook on battery system safety for the broad audience [3]. [1] Survey on standards for batteries and system integration with them. VITO, 2015. [Online] batterystandards.vito.be.[2] Analysis of Battery Safety and Hazards’ Risk Mitigation. Ashtiani, C.N. 2008, ECS Transactions, Vol. 11, pp. 1-11 .[3] STALLION Handbook on safety assessments for large-scale, stationary, grid-connected Li-ion energy storage systems, DNV GL, Arnhem 2015. [Online] stallion-project.eu Figure 1

Communication Through Gap Junctions in the Endothelium.

A swarm of fish displays a collective behavior (swarm behavior) and moves "en masse" despite the huge number of individual animals. In analogy, organ function is supported by a huge number of cells that act in an orchestrated fashion and this applies also to vascular cells along the vessel length. It is obvious that communication is required to achieve this vital goal. Gap junctions with their modular bricks, connexins (Cxs), provide channels that interlink the cytosol of adjacent cells by a pore sealed against the extracellular space. This allows the transfer of ions and charge and thereby the travel of membrane potential changes along the vascular wall. The endothelium provides a low-resistance pathway that depends crucially on connexin40 which is required for long-distance conduction of dilator signals in the microcirculation. The experimental evidence for membrane potential changes synchronizing vascular behavior is manifold but the functional verification of a physiologic role is still open. Other molecules may also be exchanged that possibly contribute to the synchronization (eg, Ca(2+)). Recent data suggest that vascular Cxs have more functions than just facilitating communication. As pharmacological tools to modulate gap junctions are lacking, Cx-deficient mice provide currently the standard to unravel their vascular functions. These include arteriolar dilation during functional hyperemia, hypoxic pulmonary vasoconstriction, vascular collateralization after ischemia, and feedback inhibition on renin secretion in the kidney.

AUTOMATED CELL MIGRATION TRACKING TECHNIQUE: A REVIEW

Automated cell migration tracking is important in detecting the cell movement in order to help in cell status analysis especially when there are a huge numbers of cells in one image frame. Automated cell tracking processes involve detecting, segmentation and labelling the cell. Each step is crucial and will affect the next step. The common problems are cell proliferation, overlapping and clustering. Consequently, this review not only focuses on the overview of current techniques used to complete the cell migration tracking tasks, but also the comparison of these techniques and some suggested future work(s).

Construction of a biocompatible decellularized porcine hepatic lobe for liver bioengineering.

One of the major obstacles in applying decellularized organs for clinical use is the recellularization step, during which huge numbers of cells are required to develop whole livers. We established a simple protocol for constructing a bioartificial hepatic lobe and investigated its biocompatibility. The right lateral lobe of porcine liver was decellularized using 0.1% sodium dodecyl sulfate through the right branch of the portal vein. Decellularized lobes were evaluated by histological and biochemical analyses. DNA content was quantified to validate the decellularization protocol. The presence of immunogenic and pathogenic antigens was checked to exclude potential rejection and thrombosis after xenotransplantation. Xeno-reactivity of decellularized tissue against human peripheral blood mononuclear cells was examined. Cytotoxicity was evaluated against hepatocarcinoma cells. Finally, scaffolds were incubated in collagenase for biodegradation testing. The decellularized lobe preserved the three-dimensional architecture, ultrastructure, extracellular matrix components, and vasculature. Scaffolds were almost depleted of DNA in addition to antigenic and pathogenic antigens, which are considered barriers to xenotransplantation. The human immune response against scaffolds was considered non-significant. Our matrices were biocompatible and biodegradable. We successfully developed a non-cytotoxic, non-immunogenic, and biodegradable porcine hepatic lobe for future liver regeneration and bioengineering.

In vivo stem cell transplantation using reduced cell numbers.

Dental pulp stem cell (DPSC) characterization is essential for regeneration of a dentin/pulp like complex in vivo. This is especially important for identifying the potential of DPSCs to function as stem cells. Previously reported DPSC transplantation methods have used with huge numbers of cells, along with hydroxyapatite/tricalcium phosphate (HA/TCP), gelatin and fibrin, and collagen scaffolds. This protocol describe a transplantation protocol that uses fewer cells and a temperature-responsive cell culture dish.

Human Decidua-Derived Mesenchymal Cells Are a Promising Source for the Generation and Cell Banking of Human Induced Pluripotent Stem Cells.

Placental tissue is a biomaterial with remarkable potential for use in regenerative medicine. It has a three-layer structure derived from the fetus (amnion and chorion) and the mother (decidua), and it contains huge numbers of cells. Moreover, placental tissue can be collected without any physical danger to the donor and can be matched with a variety of HLA types. The decidua-derived mesenchymal cells (DMCs) are highly proliferative fibroblast-like cells that express a similar pattern of CD antigens as bone marrow-derived mesenchymal cells (BM-MSCs). Here we demonstrated that induced pluripotent stem (iPS) cells could be efficiently generated from DMCs by retroviral transfer of reprogramming factor genes. DMC-hiPS cells showed equivalent characteristics to human embryonic stem cells (hESCs) in colony morphology, global gene expression profile (including human pluripotent stem cell markers), DNA methylation status of the OCT3/4 and NANOG promoters, and ability to differentiate into components of the three germ layers in vitro and in vivo. The RNA expression of XIST and the methylation status of its promoter region suggested that DMC-iPSCs, when maintained undifferentiated and pluripotent, had three distinct states: (1) complete X-chromosome reactivation, (2) one inactive X-chromosome, or (3) an epigenetic aberration. Because DMCs are derived from the maternal portion of the placenta, they can be collected with the full consent of the adult donor and have considerable ethical advantages for cell banking and the subsequent generation of human iPS cells for regenerative applications.

Simplicial models of trace spaces

In this paper, we develop a systematic approach describing spaces of directed paths ‐ up to homotopy equivalence ‐ as finite prodsimplicial complexes, ie with products of simplices as building blocks. This method makes use of a certain poset category of binary matrices related to a given model space. It applies to a class of directed spaces that arise from a certain class of models of computation ‐ still restricted but with a fair amount of generality. In the final section, we outline a generalization to model spaces known as Higher Dimensional Automata. In particular, we describe algorithms that allow us to determine not only the fundamental category of such a model space, but all homological invariants of spaces of directed paths within it. The prodsimplical complexes and their associated chain complexes are finite, but they will, in general, have a huge number of cells and generators.

Controlling Spiral Waves in a Model of Two-Dimensional Arrays of Chua's Circuits

A model of two-dimensional arrays of Chua's circuits is numerically investigated. In a certain parameter region the spatiotemporal system has both synchronized oscillation and spiral wave attractors. Feedback pinnings are suggested to migrate the system from the spiral wave state to the coherent oscillation. The influences of the pinning density, forcing strength, and different pinning distributions on the driving effect are investigated. It is shown that some properly designed control schemes may reach very high control efficiency, i.e., killing a spiral wave consisting of a huge number of cells by injecting only very few cells. The wide applications of the approach are addressed.

Immune Network Theory

Theoretical ideas have played a profound role in the development of idiotypic network theory. Mathematical models can help in the precise translation of speculative ideas into quantitative predictions. They can also help establish general principles and frameworks for thinking. Using the idea of shape space, criteria were introduced for evaluating the completeness and overlap in the antibody repertoire. Thinking about the distribution of clones in shape space naturally leads to considerations of stability and controllability. An immune system which is too stable will be sluggish and unresponsive to antigenic challenge; one which is unstable will be driven into immense activity by internal fluctuations. This led us to postulate that the immune system should be stable but not too stable. In many biological contexts the development of pattern requires both activation and inhibition but on different spatial scales. Similar ideas can be applied to shape space. The principle of short-range activation and long-range inhibition translates into specific activation and less specific inhibition. Application of this principle in model immune systems can lead to the stable maintenance of non-uniform distributions of clones in shape space. Thus clones which are useful and recognize antigen or internal images of antigen can be maintained at high population levels whereas less useful clones can be maintained at lower population levels. Pattern in shape space is a minimal requirement for a model. Learning and memory correspond to the development and maintenance of particular patterns in shape space. Representing antibodies by binary strings allows one to develop models in which the binary string acts as a tag for a specific molecule or clone. Thus models with huge numbers of cells and molecules can be developed and analyzed using computers. Using parallel computers or finite state models it should soon be feasible to study model immune systems with 10(5) or more elements. Although idiotypic networks were the focus of this paper, these modeling strategies are general and apply equally well to non-idiotypic models. Using bit string or geometric models of antibody combining sites, the affinity of interaction between any two molecules, and hence the connections in a model idiotypic network, can be determined. This approach leads to the prediction of a phase transition in the structure of idiotypic networks. On one side of the transition networks are small localized structures much as might be predicted by clonal selection and circuit ideas.(ABSTRACT TRUNCATED AT 400 WORDS)