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Abstract: Circulating hemocytes from larval stages of the paper wasp Polistes dominulus were characterized by light and transmission electron microscopy. Three types were identified: prohemocytes, plasmatocytes and granulocytes. The first two are agranular cells while the latter present typical cytoplasmic inclusions called granules. Plasmatocytes differ from prohemocytes being larger, showing lower nucleus/cytoplasm ratio and they possess many phagolysosomes. The substantial uniformity of most subcellular features and the presence of “intermediate forms” support the “single-cell theory” i.e., there is only one cell line that originates from the prohemocyte and leads to the granular cell passing through the plasmatocyte. This hypothesis seems to be confirmed by functional tests. Indeed, most part of cells adheres to the glass and is able to phagocytize fluorescent microspheres. [Copyright &y& Elsevier]

In this paper, the Peukert's equation was studied experimentally and theoretically at various discharge currents for lithium-ion cells. The classical Peukert's equation is not applicable at small discharge currents as according to this equation, at the discharge current decrease, the capacity released by the cells tends to infinity. The generalized Peukert's equation C = Cm /(1+(i/i0)n) corresponds well to the experimental data obtained at small and middle discharge currents. However at high discharge currents, the capacity released by the lithium-ion cells drops much faster than it is predicted by the known Peukert's equation generalizations. In this paper both experimentally and theoretically, it is proved that the reason of the sharp decrease of the cells capacity at high discharge currents is the voltage drop at cells internal resistance. Based on the obtained results, the following equation was proposed: C = Cm (1−i/i1)/((1−i/i1)+in/i0n). This equation corresponds well to the experimental data at any discharge currents, as it takes into consideration the voltage drop, caused by the cell internal resistance. [ABSTRACT FROM AUTHOR]

Target cells contagion has sparked the necessity of a multiple target cell model with chronic infection and intracellular delay (MTC-CI-ID). This paper seeks to advance a viral dynamical model with multiple target cells and corroborate the global stability of their steady states. Hence, the affiliation of the virus with two classes of target cells, CD4 + Tcells and macrophage. The time delay amidst viral entry and the output of virions were intimated and the basic reproductive number was procured, as the long term behavior of the model and less than unity. The contagious free equilibrium E 0 was unveiled as locally and globally asymptotically stable. The conditions of an infected CD4 + Tcell and macrophage on viral production were engaged. It was ascertained that CD4 + Tcell accounts for larger amounts of virions in the blood as per macrophage cells. Hence, varying time delay has no impact on peak viral levels, but only shelves the viral peaking time. The adopted model has unrestrained bearing on HIV-1 therapy. [ABSTRACT FROM AUTHOR]

For many practical applications, fully coupled three-dimensional models describing the behavior of lithium-ion pouch cells are too computationally expensive. However, owing to the small aspect ratio of typical pouch cell designs, such models are well approximated by splitting the problem into a model for through-cell behavior and a model for the transverse behavior. In this paper, we combine different simplifications to through-cell and transverse models to develop a hierarchy of reduced-order pouch cell models. We give a critical numerical comparison of each of these models in both isothermal and thermal settings, and also study their performance on realistic drive cycle data. Finally, we make recommendations regarding model selection, taking into account the available computational resource and the quantities of interest in a particular study. [ABSTRACT FROM AUTHOR]

In order to understand the lithium-ion battery (LIB) failing behavior and to prevent failures and their consequences, different LIB safety tests, also called abuse tests, have been developed. This paper focuses on thermal runway (TR) triggered by overtemperature, overcharge and nail-penetration. It shows the setup and the results of the three different TR triggers on two different cell types in a custom-made TR reactor. The investigated cell types are state-of-the-art automotive pouch and hard case cells. The results are discussed in three main categories: thermal behavior, vent gas production and vent gas composition. The results and findings are supposed to be valuable for battery pack designer, car manufacturer and testing institutions for the development of future battery testing facilities and regulations. [ABSTRACT FROM AUTHOR]

This paper presents the “dual electrochemical cell” (DEC) method, a new technique that allows monitoring of corrosion current (icorr) in real time with a corrosion potential (Ecorr) that may change with time. In this method, the Ecorr of a metal corroding in a solution containing the oxidant of interest is measured in the 1st cell. This potential is then continuously applied in real time to a second cell using the same metal electrode in the same solution but free of the oxidant, and the current of the 2nd cell, which represents the icorr of the 1st cell, is monitored. This setup allows direct measurement of icorr without having to polarize the corroding electrode away from Ecorr. The advantages of DEC over conventional methods are that it does not require the corroding system to be at steady state, and avoids any ambiguities associated with the extrapolation of the measured current-potential relationship to extract icorr. The icorr values obtained using the DEC method were compared with those obtained using conventional polarization techniques, using dissolved metal concentrations and surface analysis observations, and the results showed that the DEC method provides the most accurate measurement of icorr. [ABSTRACT FROM AUTHOR]

Traditional two dimensional cell culture has enabled great strides in biomedicine but needs to be improved to be able to keep up with the demands of modern biomedical research. 2D monolayer culture cannot replicate tissue responses and needs to be supplemented with extensive animal research. Growing cells in three dimensional scaffolds provides a more functional model for biomedical research than traditional monolayer culture. Depending on the needs and the complexity of the model there are several ways that 3D models can be initiated. Simple spheroids can be grown in low adherence plates and in hanging drops while larger spheroids and co-cultured ones need to be grown in systems with greater support such as hydro gels. The system that offers the greatest flexibility is the magnetic levitation approach. In the paper we offer a brief resume to various 3D methods and their characteristics to ease the choice of methods for implementing 3D cell culture techniques. Klasična dvodimenzionalna stanična kultura omogućila je veliki napredak u biomedicini, ali potrebno ju je unaprijediti kako bi odgovorila zahtjevima modernih biomedicinskih istraživanja. Monoslojna 2D kultura ne može replicirati tkivni odgovor i potrebno ju je nadopuniti iscrpnim istraživanjima na životinjama. Uzgoj stanica u trodimenzionalnim potpornim sustavima rezultira funkcionalnijim biomedicinskim modelima u odnosu na klasične monoslojne kulture. U ovisnosti o potrebama i složenosti istraživanja, 3D modeli se mogu formirati na nekoliko načina. Jednostavni sferoidi se mogu uzgojiti kao viseća kap te na slabo adherirajućim površinama dok se veliki sferoidi i ko-kulture uzgajaju u jačim sustavima podrške poput hidrogelova. Magnetska levitacija je jedan od načina pripreme koji omogućuje najveću fleksibilnost u uzgoju sferoida. U radu ćemo ponuditi kratki pregled različitih 3D modela i njihovih karakteristika kako bismo olakšali odabir metode kod uspostave 3D kulture. [ABSTRACT FROM AUTHOR]

Global warming is increasing at the alarming rate in the recent years. One of the best solutions to reduce the global warming is generation of power from the carbon neutral and negative technologies. In view of this, harvesting energy from the photosynthesis is one of the best viable solution. The Microphotosynthetic cell (μPSC), presented in this work, functions on the principle of photosynthesis and respiration. Typical power produced by a μPSC varies in the range of 0.1–10 mW. In this paper, we discussed the potential applications of the Microphotosynthetic power cells to the automotive sector and Autonomous Vehicles (AV). [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries are promising energy storage devices in which high‐energy‐density and superior safety can be obtained by efficient cell design and the use of nonflammable solid electrolytes, respectively. This paper presents a systematic study of experimental factors that affect the electrochemical performance of all‐solid‐state batteries. The morphological changes in composite electrodes fabricated using different mixing speeds are carefully observed, and the corresponding electrochemical performances are evaluated in symmetric cell and half‐cell configurations. We also investigate the effect of the composite electrode thickness at different charge/discharge rates for the realization of all‐solid‐state batteries with high‐energy‐density. The results of this investigation confirm a consistent relationship between the cell capacity and the ionic resistance within the composite electrodes. Finally, a concentration‐gradient composite electrode design is presented for enhanced power density in thick composite electrodes; it provides a promising route to improving the cell performance simply by composite electrode design. [ABSTRACT FROM AUTHOR]

Stable long-term cycling and solid-electrolyte-interphase (SEI) formation are key challenges in the design of Si/graphite composites as Li-ion battery (LIB) anode materials. Typically, these long-term cycling properties are examined in flooded half-cell settings making use of a Li-metal counter electrode and a Si/graphite working electrode. This form factor has the advantage of offering an unlimited supply of Li-ions and electrolyte, thus isolating performance degradation to the passivation of the working electrode. However, halfcell studies are ineffective in revealing performance and degradation mechanisms of the Si/graphite composite in a more commercially realistic full cell setting. This paper outlines an operando acoustic technique that can offer insights on SEI formation and capacity degradation of Si/graphite composites in a full cell setting. Through a combination of electrochemical and chemical analyses, we show that increasing passivation of the silicon particles in the Si/graphite composite anode is correlated with an increase in the acoustic time-of-flight shift. We further show that temporary loss of the acoustic signal during the first cycle is associated with significant gassing of the cell. The operando acoustic technique outlined here is low-cost, simple to setup and has the potential for localized resolution, indicating usefulness in commercial-scale Si/graphite cell quality control and diagnosis. [ABSTRACT FROM AUTHOR]

• LSFM is studied as symmetrical electrode of SOEC for direct pure CO 2 electrolysis. • The cell with LSFM shows high current density of 1.107 A/cm2 at 800 °C @2.0 V. • The cell shows CO production rate at 800 °C@2.0 V of 6.438 mL/(min cm2). In this paper, we study the perovskite La 0.6 Sr 0.4 Fe 0.9 Mn 0.1 O 3- δ (LSFM) as both the cathode and anode in a symmetrical solid oxide electrolysis cell (SOEC) for direct high-temperature electrolysis of pure CO 2. The cell with a configuration of LSFM-GDC|GDC||YSZ||GDC|LSFM-GDC performs with perfect electrochemical properties with a polarization resistance of 0.068 Ω·cm2 and a current density of 1.107 A/cm2 at 800 °C and 1.744 A/cm2 at 850 °C under an operating voltage of 2.0 V. The corresponding CO production rate at 800 °C and 2.0 V is 6.438 mL/(min·cm2). These results confirm that La 0.6 Sr 0.4 Fe 0.9 Mn 0.1 O 3-δ can act as an excellent electrode material in a symmetrical SOEC for electrolysis of pure CO 2. [ABSTRACT FROM AUTHOR]

In this paper, the possibility of using generalized Peukert's equations C =Cm/(1 + (i/i0)n), C = 0.522Cmtanh((i/i0)n/0.522)/(i/i0)n, and C = Cmerfc((i/ik - 1)/(1/n))/erfc(-n) for the calculation of lithium-ion cells' released capacity at different discharge currents is analyzed. It is proven that these equations correspond well to the experimental data over the entire change range of the discharge currents. Furthermore, it is demonstrated that the parameter n depends on neither cell capacity nor its format or manufacturer; however, it grows with an increase of the ratio i0/m (or ik/m), which depends on an electrode's effective thickness and the electrochemical system of the lithium-ion cells. Additionally, it is possible to consider the dependence of a lithium-ion cell's released capacity on a discharge current value as the statistical phase transition subjected to the normal distribution law. The proposed statistical mechanism explains the changes of the parameters n and i0 (ik) based on the type of battery studied. [ABSTRACT FROM AUTHOR]

This paper presents a two-dimensional Markov traffic model of the mobile users' network where there exist handover calls from the surrounding cells to the considered cell and where, also, primary calls are generated. The two emphasized types of calls form together mixed traffic. The new, two-dimensional model allows us to calculate some characteristic variables for the systems, which may not be determined based on the analysis of one-dimensional model. The developed simulation program is verified comparing the obtained system state probabilities as also primary and handover calls loss rate to the corresponding values from the calculation process. We analyzed cells with a number of channels reserved only for handover calls. This system performances are compared to the performances of some other systems from literature and it is proved that their characteristics are comparable whereby our system improves handover calls dropping rate. It is also proved that users' speed increase and cell radius decrease cause both primary and, especially, handover calls loss rate increase. The results of calculation and simulation are obtained after a number of iterations (calculation or simulation cycles), where the new loss probability values from one iteration become the input values for the next iteration. In the case that call loss values do not converge during simulation, we implemented the original algorithm for input call loss probability estimation for the next iteration. [ABSTRACT FROM AUTHOR]

Time-lapse microscopy has thoroughly transformed our understanding of biological motion and developmental dynamics from single cells to entire organisms. The increasing amount of cell tracking data demands the creation of tools to make extracted data searchable and interoperable between experiment and data types. In order to address that problem, the current paper reports on the progress in building the Cell Tracking Ontology (CTO): An ontology framework for describing, querying and integrating data from complementary experimental techniques in the domain of cell tracking experiments. CTO is based on a basic knowledge structure: the cellular genealogy serving as a backbone model to integrate specific biological ontologies into tracking data. As a first step we integrate the Phenotype and Trait Ontology (PATO) as one of the most relevant ontologies to annotate cell tracking experiments. The CTO requires both the integration of data on various levels of generality as well as the proper structuring of collected information. Therefore, in order to provide a sound foundation of the ontology, we have built on the rich body of work on top-level ontologies and established three generic ontology design patterns addressing three modeling challenges for properly representing cellular genealogies, i.e. representing entities existing in time, undergoing changes over time and their organization into more complex structures such as situations. [ABSTRACT FROM AUTHOR]

Necrosis in heart muscles can permanently hinder the natural healthy rhythm of heart pumping mechanism. The damaged muscular tissues are replaced by scar tissues and burdens the healthy muscles resulting in further attenuated functioning of heart. Since, human heart muscles cannot regenerate naturally or it has been thought so, pharmacological procedures such as using a heart assist device are followed to restore the lost function of heart. Stem cell engineering and cardiac patches offers promising prospects with their cutting edge research reports. Cardiac patches offers a viable solution as they can also function as an implant to assist in offering the mechanical support the damaged muscles were capable of. Designing cardiac patches to suit multiple functions is not only challenging but also perilous due to the target organ with which it will be interfaced. Sensor based, electrically active, miniaturized circuitry etc., poses a huge threat to the individual in whom the device/patch is implanted. In this paper, we propose a hypothesis on choosing β-PVDF based nanocomposites as the inimitable material for designing implantable cardiac patches. β-PVDF based nanocomposite materials is expected to exhibit piezoelectric effect and contribute to the adherence, proliferation and maturation of stem cells. Physico-chemical characterizations followed by in vitro cell line studies were performed in ought to confirm the same. The results revealed that the β-PVDF based nanocomposite material was mechanically stable and supportive in cardiomyocyte adherence and differentiation when compared to standard non piezoelectric scaffolds (control). Hence, an implantable β-PVDF based novel electrospun nanocomposite scaffold is hypothesized to be the hour of need in conjugation with stem cell engineering for repairing damaged heart muscles. [ABSTRACT FROM AUTHOR]

A 78-year-old woman within 3 years of of bilateral silicone gel breast implants for breast reconstruction due to breast cancer presented with heaviness and swelling in her right breast. Cytology of the aspirated fluid confirmed breast implant associated anaplastic large cell lymphoma (BIA-ALCL), and the patient underwent removal of implant and total capsulectomy. Breast implantassociated anaplastic large cell lymphoma is a rare entity, but if diagnosed early is a curable condition. This paper presents the first confirmed case of breast implant associated anaplastic large cell lymphoma in Hawai'i. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents Large Eddy simulations of flow and acoustic computations around 2D and 3D airfoils using a novel type of mesh called voxel mesh. Voxel mesh refers to the mesh that has different number of nodes in the neighbouring cell layers. Voxel mesh has many advantages such as creating cells with minimum skewness, automatic mesh generation and uniformity in cell shapes and sizes. The voxel meshes aren’t yet validated in boundary layer computations. In this paper we validate the use of voxel meshes in boundary layer computations in 2D and 3D airfoils. Six cases were tried out in the research three 2D meshes and three 3D cases were tried out. Each case was simulated at Reynolds number 2.83×105 and attack angle of 90. Flow field computation was done by FrontFlowBlue-7.2 software the acoustic computation was done by using FrontFlowBlue-Acoustic2.2 software. The results obtained from the simulations were compared with the experimental values. The use of voxel meshes to resolve the boundary layer in turbulent fluid flows could be validated using 2D airfoils. Therefore voxel meshes were used in 3D airfoil flow computations. After successful flow computations the source fluctuations in the flow was used for the acoustic computations. The sound pressure levels computed from the acoustic computations were compared with the experimental values. Some oscillation in the pressure could be observed due to the step like structure at the surface of voxel mesh but these variations were less apparent in meshes that had smaller cells. [Copyright &y& Elsevier]

Leukocyte segmentation is one of the essential steps in an automatic leukocyte recognition system. Due to the complexity of the overlapping cell images, methods for leukocyte segmentation are still needed. In this paper, we first construct a combined image by saturation and green channels to extract the nucleus and in turn locate a cursory circular region of the leukocyte. Then the boundary of the leukocyte is represented by the polar coordinate. We determine the overlapping area by polar angle detection. Finally, another combined image is built based on the red and blue channels of the sub image covering the overlap to segment the leukocyte. The paper reports a promising segmentation for 60 microscopic cell images. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we investigate a design of biological excitable media based on non-excitable cells and intercellular calcium signaling mechanisms. The calcium induced calcium release mechanism in non-excitable cells is exploited to transform the non-excitable cells into excitable media that propagate calcium signals cell-to-cell. The biological excitable media investigated in this paper represent versatile media for controlling biological systems owing to the nature and function of calcium signals as the universal second messenger for the cell. The enhanced calcium excitability of non-excitable cells is experimentally demonstrated and a mathematical model is developed to investigate the condition for non-excitable cells to increase the calcium excitability. [ABSTRACT FROM AUTHOR]

Summary: Substrate topography, independently of substrate chemistry, has been reported to have significant effects on cell behaviour. Based on the use of fabrication techniques developed by the silicon microtechnology industry, numerous studies can now be found in the literature analyzing cell behaviour as to various micro- and nano-features such as lines, wells, holes and more. Most of these works have been found to relate the micro- and nano-sized topographical features with cell orientation, migration, morphology and proliferation. In recent papers, even the influence of substrate nanotopography on cell gene expression and differentiation has been pointed out. However, despite the large number of papers published on this topic, significant general trends in cell behaviour are difficult to establish due to differences in cell type, substrate material, feature aspect-ratio, feature geometry and parameters measured. This paper intends to compile and review the relevant existing information on the behaviour of cells on micro- and nano-structured artificial substrates and analyze possible general behavioural trends. [Copyright &y& Elsevier]

Summary: It was postulated previously that a progressive increase in cell hydration, induced by successive genetic or epigenetic changes, is the basic mechanism of multistep carcinogenesis, and also that the degree of malignancy increases with the degree of cell hydration. These hypotheses implied that increased cell hydration is a common factor promoting both tumor growth and metastasis, and that metastatic potential increases with the degree of cell hydration. This paper discusses these implications in relation to current concepts of genetic mechanisms determining the acquisition of metastatic potential. It was also postulated previously that the enhancement of metabolic activity by increased cell hydration will increase the ability of tumor cells to compete for nutrients with their normal counterparts. This effect may favor the preferential selection of cells whose genotypes confer the greatest increase in cell hydration and which, on the present hypothesis, would be those with the greatest capacity for metastasis. An important feature of this “common factor” hypothesis is that it suggests a biochemical explanation for DNA-microarray data showing a similarity between the gene expression patterns associated with both tumor growth and metastasis, while the postulated role of genes causing increased cell hydration might explain the apparent acquisition of metastatic potential at an early stage of tumorigenesis. Previous investigations were consistent with the hypothesis that various factors promoting carcinogenesis may do so by increasing cell hydration. A survey of the literature showed that all of these factors also promote cell motility, migration or metastasis, and provided evidence that these effects could be attributed to the associated increase in cell hydration. Methods are suggested for testing the hypothesis, and the paper concludes by emphasizing the need for more research on the biochemistry of cancer, and on the role of water as a biochemical factor of particular importance, not only in carcinogenesis, but in many other aspects of cell biology. [Copyright &y& Elsevier]

Abstract: Trafficking of cells between the fetus and its mother provides indirect clues to the underlying pathophysiology of pregnancy. Georg Schmorl first documented the presence of fetal cells in the maternal body and emphasized the importance of the placenta in eclampsia. Although his classic paper, written in 1893, is widely cited today, few investigators have actually read the paper, as it was published in German [Schmorl G., Pathologisch-anatomische Untersuchungen über Puerperal-Eklampsie. Verlag FCW Vogel, Leipzig; 1893]. Our goal was to translate the paper into English and critically re-evaluate its conclusions from a 21st century perspective. Schmorl was remarkably astute in his assessment of the pathologic changes that were seen in the 17 women on whom he performed complete autopsies. He found similar severe changes in all of the women, implying a common pathogenesis. This was in direct contrast to the then current doctrine. He was the first to observe the presence of thrombi containing multinucleated syncytial giant cells in the lungs of the women and speculated that they were of placental origin. To support his hypothesis he performed animal experiments. He also recognized that feto-maternal trafficking occurred in normal gestations but was increased in pregnancies affected by eclampsia. Using sophisticated molecular techniques we can now precisely confirm what Schmorl so elegantly described. [Copyright &y& Elsevier]

Rapid re-endothelialization following balloon angioplasty can reduce restenosis by inhibiting smooth muscle cell migration and proliferation. However, formation of a neointima following angioplasty can be inhibited due to endothelial cell dysfunction and denudation. The purpose of this study was to evaluate mechanical tensile stress as a cause of endothelial cell dysfunction. The Flexercell strain unit was utilized to generate both short-term cyclic and static tensile strain on cultured bovine aortic endothelial cells (BAECs). Before analysis of this loading on BAECs, strain behaviour of the Flexercell system and DNA assay conditions were optimized. This paper demonstrates that, when compared with unloaded controls, 4-h cyclic loading at 4 per cent elongation and 0.1 Hz, and static loading at 4 per cent elongation cause a 44 and 70 per cent decrease in DNA synthesis respectively. In a companion paper, it is demonstrated that low DNA synthesis levels in mechanically loaded cells can be increased by incubation with Ap4A and/or NO donors. [ABSTRACT FROM AUTHOR]

Rapid re-endothelialization following balloon angioplasty can reduce restenosis by inhibiting smooth muscle cell migration and proliferation. However, formation of a neointima layer following angioplasty can be inhibited due to endothelial cell dysfunction and denudation. In a companion paper, it has been illustrated that mechanical loading causes a decrease in DNA synthesis in bovine aortic endothelial cells (BAECs) thus rendering them dysfunctional. The purpose of this study was to overcome BAEC dysfunction by incubation with pharmacological agents to increase DNA synthesis. Previous studies demonstrated that the adenosine dinucleotides Ap[sub 4]A and Ap[sub 2]A induced nitric oxide (NO) production from BAEC while Ap[sub 3]A, Ap[sub 5]A and Ap[sub 6]A did not. This paper demonstrates that Ap[sub 4]A and Ap[sub 2]A induce a 1.46- and 1.16-fold increase in DNA synthesis in mechanically stressed BAECs respectively, while Ap[sub 3]A, Ap[sub 5]A and Ap[sub 6]A do not. Additionally, NOC-18, a slow NO release NO donor, significantly increases DNA synthesis in mechanically stressed BAECs without affecting unloaded cells. These results are consistent with NO inducing DNA synthesis in mechanically stressed BAECs. [ABSTRACT FROM AUTHOR]

The use of semantic technologies, such as ontologies, to describe and analyse biological systems is at the heart of systems biology. Indeed, understanding the behaviour of cells requires a large amount of context information. In this paper, we propose an ontology entitled ”Biomolecular Network ontology” using the OWL language. The BNO ontology standardises the terminology used by biologists experts to address issues including semantic behaviour representation, reasoning and knowledge sharing. The main benefit of this proposed ontology is the ability to reason about dynamical behaviour of complex biomolecular networks over time. We demonstrate our proposed ontology with a detailed example, the bacteriophage T4 gene 32 use case. [ABSTRACT FROM AUTHOR]

This paper presents motion of neutrophil in a confined environment. Many experimental and theoretical studies were performed to show mechanics and basic principles of the white blood cell motion. However, they were mostly performed on flat plates without boundaries. More realistic model of flow in the capillaries based on confinement, curvature and adequate dimensions is applied in our experiments. These conditions lead to cell motion with deformability and three-dimensional character of that movement. Neutrophils are important cells for human immune system. Their motion and attachment often influence several diseases and immune response. Hence, studies focus on that particular cell type. We have shown that deformability of the cell influences its velocity. Cells actively participate in the flow using the shear gradient to advance control motion. The observed neutrophil velocity was from 1 up to 100 μ m / s . [ABSTRACT FROM AUTHOR]

This paper describes a method of evaluating the difference in chromatin content of cervical cancer cells and normal cells by applying image processing techniques. Among the various methods tot texture analysis, this paper adopts structural analysis to achieve high accuracy. The analysis procedure is as follows. (1) The location of chromatin is determined by extracting the pixel where the gray level is locally maximum. (2) The image is segmented by any of Volonoi neighborhood, areas expansion by a difference direction, or directed tree. (3) Threshold processing is applied to the segmented subimages. (4) The size and gray level of the extracted areas are determined. A feature extraction experiment for the cell is performed by the above procedure. From these results, the following observations are obtained. (i) The method of local maximum is useful in determining the chromatin location. (ii) The extraction can be improved by local thresholding. (iii) The mean, variance and mean gray level of the cell, in the extracted chromatin area, as well as the mesa and variance of the minimum distance among local maxima, are seen to be useful feature parameters in the discrimination of normal and malignant chromatins. [ABSTRACT FROM AUTHOR]

The present paper presents a mechanistic model of cerebral autoregulation, in which the dual effects of the arachidonic acid metabolites 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs) on vascular smooth muscle mediate the cerebrovascular adjustments to a change in cerebral perfusion pressure (CPP). 20-HETE signalling in vascular smooth muscle mediates myogenic feedback to changes in vessel wall stretch, which may be modulated by metabolic feedback through EETs released from astrocytes and endothelial cells in response to changes in brain tissue oxygen tension. The metabolic feedback pathway is much faster than 20-HETE-dependent myogenic feedback, and the former thus initiates the cerebral autoregulatory response, while myogenic feedback comprises a relatively slower mechanism that functions to set the basal cerebrovascular tone. Therefore, assessments of dynamic cerebral autoregulation, which may provide information on the response time of the cerebrovasculature, may specifically be used to yield information on metabolic feedback mechanisms, while data based on assessments of static cerebral autoregulation represent the integrated functionality of myogenic and metabolic feedback. [ABSTRACT FROM AUTHOR]

This section presents technical abstracts on police science. In the article, Multiple Thickness Cell Assemblies--Application to Ultraviolet Spectrophotometry, D. D. Tunnicliff has devised multiple cell assemblies with cells of varying thicknesses to take advantage of varying cell length rather than concentrations in ultraviolet absorption spectrophotometry. The article, Plastic Vessel for pH Measurements of Small Samples, by Kenneth M. Richter, furnished dimensions and sketches of an adapter shaped to the Beckman standard electrodes for samples as small as 0.25 ml. A shoulder in one well of the adapter serves to prevent damage to the calomel electrode. The paper, Control of Fine Chemicals and Pharmaceuticals--Report for Analysts by W. B. Fortune, was presented at the Symposium on Analysis of Fine Chemicals and Pharmaceuticals at the American Chemical Society meeting in Atlantic City, New Jersey in September, 1956. The paper points out the increasingly difficult problems of identification and analysis of the many new drugs and chemicals being produced. Classical methods are inadequate, and new methods are hardly keeping pace with development and production of new products. Of particular interest to the Forensic Chemist or Criminalist are the comments about the need of applying confirmatory tests and not relying on single or inadequate identification tests.

• We propose a robust approach to segment and identify various types of cells robustly. • We utilize the Gabor filter enhanced gradients to segment the cell foreground. • We compare state of the art threshold selection methods quantitatively to select the optimal one. • We combine iterative erosion and area-constrained ultimate erosion to separate the connected cells. Research on cell segmentation is experiencing growing pains that need to be addressed for developing generic and robust techniques. The diversity of cells is growing rapidly and the demand for segmenting different types of cell images continue to increase in recent years. It is still very challenging for existing methods to segment various types of cells automatically and robustly. In this paper, we try to address this challenge by proposing an approach that is capable of segmenting various types of cells robustly. To avoid the effect of the global intensity variations, the gradients of cells are computed and then smoothed by the Gabor filter to generate the gradient image with increased intensity uniformity. To find the optimal method for cell foreground segmentation, we evaluated and compared state of the art threshold selection methods extensively. The slope difference distribution (SDD) method was testified as the optimal threshold selection method for cell segmentation and its optimal parameters were obtained in this paper based on a variety of cell images. We tested several morphological erosion methods and combined the iterative erosion method and the area-constrained ultimate erosion method to separate the connected cells robustly. Thirteen types of cells were used to compare the proposed approach with state of the art approaches. The quantitative comparison showed that the proposed approach achieved the highest average F-measure accuracy, 95.61 %. Thus, the proposed approach has the potential to be useful for various microscopic applications. [ABSTRACT FROM AUTHOR]

Fatigue is a common mode of mechanical failure which occurs when a material is subjected to repeated cycles at a strain level less than that needed for monotonic fracture. Fatigue has been observed and measured in many different materials but, until recently, not in cells. We devised a novel experiment which allowed us to create both monotonic failure and fatigue in the cellular processes of osteocytes within samples of bone (Dooley et al., European Cells and Materials 2014). In the present paper, we describe the results of further experiments and a computer simulation, which has allowed us to estimate the strain history of each sample tested and thus present, for the first time, strain/life data for cells. Failure occurred during the first cycle at strains of 0.1–0.2; at lower strains failure occurred after a number of cycles which depended inversely on the applied strain range. Scatter in the strain/life data was reduced when we allowed for the effects of mean stress using the Smith–Watson–Topper parameter. We confirmed that aspects of our experimental method (the types of microcrack used and the testing of fresh versus frozen samples) did not affect the results. Such information is useful because many cell types, including the cellular processes of osteocytes, experience cyclic strain in vivo. [ABSTRACT FROM AUTHOR]

Cadmium-quantum dots (Cd-QDs) possess unique properties as optoelectronic devices for sensitive detection in food and biomedicine fields. However, the toxic effects of Cd-QDs to single cells is still controversial, due to the release mechanism of QDs to Cd2+ in situ and the cytotoxic effects of QDs and Cd2+ respectively are still unclear. In this paper, the release rule of Cd2+ from CdTe QDs within single cells was investigated in situ by using flow cytometry method and the dose-response relationships were explored. Besides, an all-inclusive microscopy system was optimized for live cell imaging to observe the real-time entry process of CdTe QDs into cells. We found that intracellular CdTe QDs and Cd2+ contents were increased based on the dosage and exposing time. A dissociated saturation of Cd2+ from CdTe QDs was exist within cells. CdTe QDs induced more serious cytotoxicity on kidney cells than hepatocytes. The toxicity of oxidative stress, cell apoptosis effects induced by CdTe QDs and Cd2+ are also in consistent with this result. This research develops analytical method to quantify the uptake and release of Cd-QDs to primary cells in situ and can provide technical support in studying the cytotoxicity portion contributed by nanoparticles (NPs) and metal ions. In this paper, new methods of quantifying the contents of Cd-QDs and Cd2+ in situ and the release mechanism of Cd2+ from Cd-QDs have been build up. Besides, the adverse oxidative stress effects induced by Cd-QDs and Cd2+ have been also studied. Image 1 • Detection of the relative contents of QDs and released Cd2+ in situ were carried out in this paper. • The entering process of CdTe QDs into cells was observed. • Dynamic dissociated saturation was existed in the dissociative process. [ABSTRACT FROM AUTHOR]

The article discusses a research paper in which the researchers found bactericidal activity of nukacin ISK-1 against Micrococcus luteus DSM 1790 and Staphylococcus simulans 22 which shows decrease in cell viability, cell lysis, and dissipation of the membrane potential. Topics discussed include nukacin ISK-1 against Bacillus subtilis JCM 1465T, leakage of small molecules, and daptomycin, a lipopeptide antibiotic.

Two increasingly common endodontic procedures, vital pulp therapy (VPT) and regenerative endodontic procedures, rely on dental tissue regeneration/repair mechanisms with the aid of biomaterials. These materials are applied in close contact to the pulpal tissue and are required to be biocompatible, form an antimicrobial seal, not induce staining, and be easy to manipulate. Historically, calcium hydroxide played an important role in VPT. However, over the last 3 decades, significant efforts in research and industry have been made to develop various biomaterials, including hydraulic tricalcium silicate cements. The present review summarized various hydraulic tricalcium silicate cements and their biological properties in clinical procedures, namely VPT and regenerative endodontic procedures. [ABSTRACT FROM AUTHOR]

Abstract: Making human tissue samples, or cells, available for research is not a trivial undertaking. Depending on where these materials come from, their use might be limited. Existing collections of diagnostic archives which are to be made available for a subsequent research use are excellent examples of research resources which give rise to a plethora of ethical and legal problems. Many of these problems are rooted in misperceptions, based on anecdotal accounts of scandals and dishonesty, but are mirrored in jurisprudence and public debate. This paper will outline some aspects of using human tissue for research purposes that have been discussed in international literature and deemed particularly problematic, try to identify the cross-cutting ethical and legal problems and, finally, contrast these with case law. It concludes that the issue is one of control rights, the relinquishing of which can only work in a sustained fashion if there is a sufficient degree of transparency and openness in the research community. [Copyright &y& Elsevier]

Objective The present paper aims to investigate the effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and N-nitrosodiethylamine (DEN) on tumorigenesis and its potential mechanism. Methods The potentials of TCDD and DEN in separation or in combination to induce malignant transformation were tested in Balb/c 3T3 cells by using a cell transformation assay method. The possible mechanism of observed effects was studied further by adding ct-naphthoflavone (α-NF), a competitive binding agent of TCDD, to the Aryl hydrocarbon receptor (AhR) pathway. The mRNA expressions of Cyplal and Cyp2a5 gene in Balb/c 3T3 cells treated by DEN and TCDD in separation or in combination with or without presence of α-NF were measured with fluorescence quantification RT-PCR technique. Results The cell transformation frequency (TF) was significantly higher in case of induction with TCDD in combination with DEN, as compared to that with either TCDD or DEN alone. These effects were not inhibited via α-NF. The mRNA expression levels of both Cyplal and Cyp2a5 were enhanced by TCDD treatment alone, but this inducible effect was blocked in cells treated by TCDD and DEN in combination. Conclusion TCDD and DEN had a significant synergistic effect on tumorigenesis when they were used in combination. AhR pathway may not be the key mechanism of this synergistic effect. Thus, it is necessary to further test the potential mechanism involved in cancer development. [ABSTRACT FROM AUTHOR]

The present paper is an investigation on the theoretical models that exercised an important role in the birth of cytology. The historical available information permits to estimate that the cellular theory suffered a development along the nineteenth century, capable of a rational reconstruction as well as the allowance to define which were the ontological and epistemological suppositions assumed. [ABSTRACT FROM AUTHOR]

Abstract: Laser microdissection can be used in forensic casework to isolate specific cell types from mixtures of biological samples. Extraction of DNA from selected cells is still required prior to STR amplification. Because of the relatively pristine nature of the recovered cells, laser microdissection is more sensitive than more traditional methods of DNA analysis, theoretically resulting in DNA profiles from less cellular material. A one-tube extraction and amplification method minimises loss of DNA through liquid transfers and reduces the potential for contamination events occurring. In this paper, the development of a one-tube method for the effective extraction of DNA from laser microdissected sperm and epithelial cells is described. The performance of the in-house method was compared to that of a commercial DNA extraction kit for extraction of DNA from sperm and the downstream compatibility with STR amplification was determined for both sperm and epithelial samples. Full Identifiler™ profiles after 28 amplification cycles were obtained from as few as 15 epithelial cells and 30 sperm. [Copyright &y& Elsevier]

Abstract: Future computing machines will have to meet increasing requirements regarding the computational power and the efficient use of resources. Whatever the technology may be, in all likelihood it will be based on parallel operation of a large number of interconnected nanoscale units. Further challenges lie in the choice of basic units and their mutual communication. Moreover, an additional design challenge comes from the sensitivity to environmental variations which is pronounced at such a low scale. Biological creations are living examples of similar designs—they are built of a number of cells, numbers ranging from one to thousands of millions. The cells are organised in a particular way and interconnected by subtle mechanisms in achieving the ultimate common goal—the preservation of viability. In doing so, living systems incessantly adapt to ever-varying environments. In this paper, we investigate adaptive mechanisms at a very low level–the protocell level–and consider a minimal living system in a form provided by chemoton theory by Tibor Ganti. We suggest that adaptive traits of the Chemoton be used as guidelines for the design of an adaptive cell within a modular man-made system. As a proof of concept, we propose a basic circuitry in silicon and argue in favour of such implementation of the proposed adaptive cell. [Copyright &y& Elsevier]

This paper reports the results of combined experimental and modeling studies of reversible solid-oxide cells. The tubular cells are fabricated using a Ni-YSZ (yttria-stabilized zirconia) fuel-electrode support, a dense YSZ electrolyte membrane, and a strontium- doped lanthanum manganate-YSZ composite air electrode. Experiments are designed to systematically vary gas-phase species partial pressures and operating temperatures. The fuels are mixtures of H2, CO, H2O, CO2, and Ar. Performance is measured under anodic (fuel cell) and cathodic (electrolysis) polarization. The models consider reactive porous-media transport within the composite electrodes, thermal chemistry on Ni and YSZ surfaces, and charge-transfer chemistry. All chemistry is modeled with elementary reversible reactions. Close coupling between experimental measurements and model-based interpretation provides a basis for establishing reaction pathways and rates. In addition to advancing fundamental understanding, the resulting detailed reaction mechanisms are valuable for incorporation into predictive models that can be used for design and optimization of fuel-cell and electrolysis systems. [ABSTRACT FROM AUTHOR]