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Prolonged quiescence of haematopoietic stem cells has been proposed to support durable haematopoiesis through clonal succession. Genetic experiments in mice have implicated the cyclin-dependent kinase inhibitor (cdki) p21Waf1 in sustaining stem cell quiescence, and the cdki p27Kip1 in inhibiting the expansion of more mature progenitor cells. The expression of these inhibitory proteins in human haematopoietic stem cell candidates has not hitherto been studied. We describe a rare subpopulation (3 × 10−7 umbilical cord mononuclear cells) of lineage-negative cells that exhibited sustained resistance over months to cytokine-induced cycling, and characterized the expression of p21Waf1 and p27Kip1 proteins in these cells. Whereas p27Kip1 was uniformly expressed in these cells, the expression of p21Waf1 in this population and in lineage-negative CD34+ cells was variable. For this rare subset of cells exhibiting prolonged quiescence, p21Waf1 may be dispensable and p27Kip1 necessary for growth arrest. [ABSTRACT FROM AUTHOR]

Heterotrimeric G-proteins transduce signals from heptahelical transmembrane receptors to different effector systems, regulating diverse complex intracellular pathways and functions. In brain, facilitation of depolarization-induced neurotransmitter release for synaptic transmission is mediated by Gsα and Gqα. To identify effectors for Gα-proteins, we performed a yeast two-hybrid screening of a human brain cDNA library, using the human Gαs protein as a bait. We identified a protein member of the synembryn family as one of the interacting proteins. Extending the study to other Gα subunits, we found that Gqα also interacts with synembryn, and these interactions were confirmed by in vitro pull down studies and by in vivo confocal laser microscopy analysis. Furthermore, synembryn was shown to translocate to the plasma membrane in response to carbachol and isoproterenol. This study supports recent findings in C. elegans where, through genetic studies, synembryn was shown to act together with Gqα regulating neuronal transmitter release. Based on these observations, we propose that synembryn is playing a similar role in human neuronal cells. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

We have shown previously that the processing of asparagine-linked oligosaccharides in baby hamster kidney (BHK) cells is blocked only partially by the glucosidase inhibitors, 1-deoxynojidmycin and A'-methyl-1-deoxynojidmycin [Hughes, R, C, Foddy, L. & Bause, E. (1987) Biochem. J. 247, 537-544], Similar results are now reported for castanospermine, another inhibitor of processing glucosidases, and a detailed study of oligosaccharide processing in the inhibited cells is reported. In steady-state conditions the major endo-H-released oligosaccharides contained glucose residues but non-glycosylated oligosaccharides, including Man9GlcNAc to Man5GlcNAc, were also present. To determine the processing sequences occurring in the presence of castanospermine, BHK cells were pulse-labelled for various times with [³H]mannose and the oligosaccharide intermediates, isolated by gel filtration and paper chromatography, characterized by acetolysis and sensitivity to jack bean α-mannosidase. The data show that Glc3Man8GlcNAc2 is transferred to protein and undergoes processing to produce Glc3Man8GlcNAc2 and Glc3Man7GlcNAc2 as major species as well as a smaller amount of Man9GlcNAc2, Glucosidase-processed intermediates, Glc1Man8GlcNAc2 and Glc1Man7GlcNAc2, were also obtained as well as a Man7GlcNAc2 species derived from Glc1Man7GlcNAc2 and different from the Man7GlcNAc2 isomer formed in the usual processing pathway. No evidence for the direct transfer of non-glucosylated oligosacchaddes to proteins was obtained and we conclude that the continued assembly of complex-type glycans in castanospermine-inhibited BHK cells results from residual activity of processing glucosidases. [ABSTRACT FROM AUTHOR]

The article presents information about abstracts of various papers presented at the 8th annual meeting of the Society for Cutaneous Ultrastructure Research that was held from May 21 to 23, 1981 in London, England. Some papers are, the study to investigate the ultrastructure of the nail plate by G. Achten, D. Parent, G. De Dobbeleer and F. Stouffs-Vanfoof, Ichthyosis hystrix type Curth-Macklin had been separated from bullous ichthyosiform erythroderma on the basis of its peculiar ultrastructural features with tonofibriltar shell formation and a high percentage of binuclear cells by I. Anton-Lamprecht, B. Kern, G. Goerz and S. Marghescu.

A laboratory technique for measuring the mobility of solutions on filter paper has been presented. Various exudates exhibited different mobilities on filter paper; this also applied to exudates of the same origin (pleura punctates). When diluted, the exudates exhibited increased mobility, indicating that the concentrations of various exudate components were of importance. The addition of cells (5 × 106 and 25 × 106 P 388 D cells/ml exudate) did not significantly change the mobility, whereas the mobility of protein fractions (human albumin and gamma globulin) was inversely related to the concentration of the solutions. These findings may he of significance to the reliability of present methods used for the quantitation of gingival exudation. [ABSTRACT FROM AUTHOR]

Background: The effects of laser therapy on normal cells are well known and accepted, but the impact of this therapy on malignant cells are not yet fully understood. This review aims to map and outline what the scientific literature addresses on the effects of laser therapy on malignant cells. Methods: This review article followed the guidelines of the PRISMA‐ScR protocol, being all the search, analysis, and selection of articles based on it. Results: After all application of the predetermined criteria, five studies were included, dated between the years 2013 and 2021. With the complete reading of the selected studies, 100% of the articles were classified as category III of the Agency for Healthcare as Research and Quality classification. Similar themes among the papers included were investigated and compared. In these five studies, the visible red and near infrared wavelengths were used, and energy densities varied between 1 and 5 J/cm2. It was observed that low‐level laser could alter the expression of cell proliferation and migration proteins, such as cyclin D1, E‐cadherin, and β‐catenin. In addition, changes related to increased cell viability and metabolism were also identified. Conclusion: The low‐level laser seems to positively regulate the proliferative, migratory, and viability capacity of neoplastic cells, depending on the protocol used. All these studies included in the review are equivalent to in vitro studies; the cells are not in such a complex environment as is an organized tissue, making it necessary to carry out more complex tests, such as in vivo research. [ABSTRACT FROM AUTHOR]

Based on the Dual cell structure display, this paper proposes an effective contrast enhancement scheme. By using the lower cell to control the backlight brightness, local dimming is realized at the pixel level. Combined with spatial filtering, the ghosting problem of the Dual cell structure display is solved. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a dynamic and location‐based power allocation mechanism is proposed which could be adopted at both macrocell (MC) and overlaid fixed/mobile small cells (SCs) to mitigate inter‐cell interference (ICI) effects in heterogeneous cellular networks (HetCNs). The proposed Dynamic Power Allocation based on User Location (DPAUL) mechanism allows both MCs and deployed fixed/mobile SCs to dynamically allocate transmit power to its serving base stations (BSs) based on the location of a user in the cell. The paper illustrates the mitigation of dynamic downlink interferences occurring due to the mobility of SCs and users. The mobility of cell and its users is analyzed by introducing the Cell‐User mobility (CUM) model in the network. The proposed DPAUL mechanism is compared with the authors' other ICI mitigation techniques: Dynamic Fixed Region Cooperation (DFRC) and Dynamic Power Allocation Mechanism (DPAM). The network metrics Sumrate, User throughput, Energy‐efficiency, and Outage probability are investigated with allocation of sub 6 GHz and mmWave spectrums at MCs and fSCs/mSCs, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Microscopy is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cardiac remodelling refers to changes in left ventricular structure and function over time, with a progressive deterioration that may lead to heart failure (HF) development (adverse remodelling) or vice versa a recovery (reverse remodelling) in response to HF treatment. Adverse remodelling predicts a worse outcome, whilst reverse remodelling predicts a better prognosis. The geometry, systolic and diastolic function and electric activity of the left ventricle are affected, as well as the left atrium and on the long term even right heart chambers. At a cellular and molecular level, remodelling involves all components of cardiac tissue: cardiomyocytes, fibroblasts, endothelial cells and leucocytes. The molecular, cellular and histological signatures of remodelling may differ according to the cause and severity of cardiac damage, and clearly to the global trend toward worsening or recovery. These processes cannot be routinely evaluated through endomyocardial biopsies, but may be reflected by circulating levels of several biomarkers. Different classes of biomarkers (e.g. proteins, non‐coding RNAs, metabolites and/or epigenetic modifications) and several biomarkers of each class might inform on some aspects on HF development, progression and long‐term outcomes, but most have failed to enter clinical practice. This may be due to the biological complexity of remodelling, so that no single biomarker could provide great insight on remodelling when assessed alone. Another possible reason is a still incomplete understanding of the role of biomarkers in the pathophysiology of cardiac remodelling. Such role will be investigated in the first part of this review paper on biomarkers of cardiac remodelling. [ABSTRACT FROM AUTHOR]

Fringe‐Field Switch (FFS) mode cell with Photo alignment technology have been widely used in many kinds of devices due to its excellent performance of LC display. In this paper, the local area cell parameter, include cell gap, pre‐tilt angle and twist angle of dosage have been compared. [ABSTRACT FROM AUTHOR]

Summary: Indoor and cell‐edge coverage has been a major issue of concern for predeployed traditional macrocell (MC)–based homogeneous cellular network. Moreover, with the extensive increase of mobile users and developments of smart and highly specified devices, user demands and activities have led to huge cellular traffic. The key solutions to these that include network upgradation, overlaying of small cells (SCs), and scaling of resources have turned out to be the major causes for intercell interference (ICI) and energy‐efficiency degradation in heterogeneous cellular networks (HetCNs). In this paper, authors have tried to analyze the downlink performance metrics of cell boundary users with MCs overlaying SCs for three‐cell circular and seven‐cell sectorized networks through frequency reuse (FR) schemes. This paper also discusses the impact of ICI being encountered by users and the effect of SCs on the energy efficiency of the network. The locations for SCs are perceived where user density is large and demands high data rate such as at hot‐spot (HS) areas, railway stations, shopping malls, working farms, and organization. The performance metrics sum rate, average user throughput, and energy efficiency are compared by employing FR‐1 (full spectrum) and FR‐3 (three subbands) among MCs and deployed SCs. For both scenarios, simulation results and analyses depict that without SCs, utilization of FR‐1 results in performance degradation due to ICI effects. However, the downlink performance of cell boundary user and energy efficiency of the network could be enhanced by overlaying SCs near cell boundaries of preexisting MCs along with the allocation of FR‐1. [ABSTRACT FROM AUTHOR]

The authors have proposed a cell voltage equalizer with an LC series circuit in a previous work. The proposed circuit, however, has the disadvantage that the equalization time tends to be longer than that of other conventional equalizers. Therefore, the authors have studied some control methods to reduce the equalization time. This paper proposes a novel equalization time reduction method using the magnitude relation of each cell voltage estimated from the equalization current for the proposed equalizer. The proposed method can reduce the equalization time without an additional voltage sensor, so the size of the equalizer is not changed and the cost is not higher than an equalizer using the conventional control method. In addition, the characteristics and the effectiveness of the proposed method were verified by the simulations and the experiments. It was confirmed that the proposed method could reduce the equalization time to about 67.7% of that of the conventional control method by the experiments. [ABSTRACT FROM AUTHOR]

MCL, Mincle and Dectin‐2 are C‐type lectin receptors expressed by subsets of myeloid cells, and their genes cluster together in the APLEC/Dectin‐2 gene complex. We have previously shown that MCL and Mincle form a heterodimer in the rat, and others have shown that MCL and Dectin‐2 form a heterodimer in the mouse. In the rat, Dectin‐2 is a pseudogene, but here, we examine the association of the three receptors in human. In co‐transfection experiments analyzed with flow cytometry and immunoprecipitation, we here show that human MCL and Mincle form a disulphide‐linked heterodimer that associates with the signalling adaptor molecule FcεRIγ, in accordance with our previous findings in the rat. In contrast to previous findings in the rat, data in this paper indicate a direct association of MCL with FcεRIγ, as previously shown for mouse MCL. We were unable to demonstrate the formation of a heterodimer between human MCL and Dectin‐2. Thus, despite similarities, there may be important differences in the conformation of these receptors between rat, mouse and human, and this may have functional consequences. [ABSTRACT FROM AUTHOR]

The error‐correcting performance of multi‐level‐cell (MLC) NAND flash memory is closely related to the block length of error‐correcting codes (ECCs) and log‐likelihood‐ratios of the read‐voltage thresholds. Driven by this issue, this paper optimizes the read‐voltage thresholds for MLC flash memory to improve the decoding performance of ECCs with finite block length. First, through the analysis of channel coding rate and decoding error probability under finite block length, the optimization problem of read‐voltage thresholds to minimize the maximum decoding error probability is formulated. Second, a cross‐iterative search algorithm to optimize read‐voltage thresholds under the perfect knowledge of flash memory channel is developed. However, it is challenging to analytically characterize the voltage distribution under the effect of data retention noise. To address this problem, a deep neural network (DNN)‐aided optimization strategy to optimize the read‐voltage thresholds is developed, where a multi‐layer perception network is employed to learn the relationship between voltage distribution and read‐voltage thresholds. Simulation results show that, compared with the existing schemes, the proposed DNN‐aided read‐voltage threshold optimization strategy with a well‐designed Low Density Parity Check (LDPC) code can not only improve the program‐and‐erase endurance but also reduce the read latency. [ABSTRACT FROM AUTHOR]

Local dimming technology can significantly improve the contrast ratio (CR) of LCD products, the more the backlight units, the higher the CR. But due to technical limitations, backlight partitions cannot be made particularly fine. By adding a layer of light control cell between backlight and display panel, the pixel‐level local dimming can be achieved. This paper proposed a high precision and high contrast algorithm based on dual‐cell LCD. The proposed method took pixel shape and position into account which can guarantee two cells matching perfectly and realize low distortion and high contrast display. [ABSTRACT FROM AUTHOR]

A list of forthcoming articles in the "Immunology" 2008 issue is presented.

The article presents a list of articles to be published in forthcoming issues of "British Journal of Haemotology." The articles include "Relapse in Common Lymphoma Subtypes: Salvage Treatment Options for Follicular Lymphoma, Diffuse Large Cell Lymphoma and Hodgkin Disease," by B. Seyfarth, A. Josting, M. Dreyling and N. Schmitz, "Guidelines on the Use and Monitoring of Heparin," by T. Baglin and "Distinct Comparative Genomic Hybridisation Profiles in Gastric Mucosa-Associated Lymphoid Tissue Lymphomas With and Without," by Y. Zhou, H. Ye, J. I. Martin-Subero, R. Hamoudi, Y.-J. Lu, R. Wang, R. Siebert, J. Shipley, P. G. Isaacson, A. Dogan and M. Q. Du.

The ability to trap precise quantities of cells or particles into confined areas has numerous applications for biological purposes. In particular, single cell trapping has received considerable attention because it permits the study of heterogeneity in a population, while trapping larger groups of cells have been used to form aggregates. Among several methods, the use of microwell offers a simple platform to capture cells or particles using hydrodynamic forces. This review examines the use of microwells in both static and microfluidic environments, and the application of microfluidic geometric arrays for trapping. This paper discusses the design and fabrication methods of microwells and compares the trapping and release techniques used in both static and microfluidics‐integrated microwells. Finally, we will summarize novel microfluidic geometric arrays used to capture cells or particles through hydrodynamic trapping. [ABSTRACT FROM AUTHOR]

Introduction: Telecytology for second opinion consultation has largely been limited by technical issues, such as the inability to focus well on cellular material. Nevertheless, international telecytology consultation was undertaken at our institution with partners in China and Italy. To overcome issues with scanning cytology slides, we adopted a cell‐block (CB) preference for teleconsultation. Methods: Telecytology consultation cases received over a 7.5‐year period were retrospectively reviewed. Cytology glass slides were scanned without Z‐stacking using different whole slide scanners. For one referring site, only haematoxylin‐eosin‐stained CBs were scanned, as well as immunostains requested by consultants. For another host centre, aspirate smears were also scanned in some cases. Results: A total of 51 non‐gynaecological cases (44 CB only) were evaluated from 48 patients. The specimens included pleural fluids (19), pancreas (14), lymph nodes (6), peritoneal fluids (2) and miscellaneous samples (10). The cytological diagnoses spectrum included 16 (31.37%) cases positive for malignancy, 7 (13.72%) positive for neoplasm, 6 (11.76%) suspicious for malignancy, 10 (19.60%) atypical, 10 (19.60%) negative for malignancy and 2 (3.92%) non‐diagnostic. In 42 (82.35%) cases, immunocytochemistry was requested. Turn‐around‐time ranged from 1.5 to 306 hours. Conclusions: Our experience shows that international telecytology for consultation purposes involving non‐gynaecological cases is feasible. A second opinion interpretation was rendered in the majority (64.7%) of cases. Utilising CB only for cytology consultations by whole slide imaging solved focus issues that typically plague evaluation of cytology aspirate smears. The role of telecytology for consultation is emerging. This paper describes the authors experience with the use of cell blocks and whole slide imaging for international telecytology consultation and outlines key factors responsible for a successful telecytology consultation service at an academic institution. [ABSTRACT FROM AUTHOR]

publisher‐imprint‐name Springer volume‐issue‐count 1 issue‐article‐count 0 issue‐toc‐levels 0 issue‐pricelist‐year 2016 issue‐copyright‐holder The Author(s) issue‐copyright‐year 2016 article‐contains‐esm No article‐numbering‐style Unnumbered article‐registration‐date‐year 2016 article‐registration‐date‐month 2 article‐registration‐date‐day 19 article‐toc‐levels 0 toc‐levels 0 volume‐type Regular journal‐product ArchiveJournal numbering‐style Unnumbered article‐grants‐type OpenChoice metadata‐grant OpenAccess abstract‐grant OpenAccess bodypdf‐grant OpenAccess bodyhtml‐grant OpenAccess bibliography‐grant OpenAccess esm‐grant OpenAccess online‐first false pdf‐file‐reference BodyRef/PDF/40169_2016_Article_87.pdf target‐type OnlinePDF issue‐type Regular article‐type ReviewPaper journal‐subject‐primary Medicine & Public Health journal‐subject‐secondary Medicine/Public Health, general journal‐subject‐collection SC11 open‐access true --> Extracellular microvesicles (ExMVs) are part of the cell secretome, and evidence has accumulated for their involvement in several biological processes. Fourteen years ago our team demonstrated for the first time that ExMVs carry functional RNA species and proteins from one cell to another, an observation that opened up the new research field of horizontal transfer of bioactive molecules in cell‐to‐cell communication. Moreover, the presence of mRNA, noncoding RNA, and miRNA in ExMVs in blood and other biological fluids opened up the possibility of employing ExMVs as new detection markers for pathological processes, and ExMVs became a target for "liquid biopsy" approaches. While ExMV‐derived mRNAs may be translated in target cells into appropriate proteins, miRNAs regulate expression of corresponding mRNA species, and both RNA‐depended ExMV‐mediated mechanisms lead to functional changes in the target cells. Following from this observation, several excellent papers have been published that confirm the existence of the horizontal transfer of RNA. Moreover, in addition to RNA, proteins, bioactive lipids, infectious particles and intact organelles such as mitochondria may follow a similar mechanism. In this review we will summarize the impressive progress in this field—14 years after initial report. [ABSTRACT FROM AUTHOR]

SUMMARY This paper assumes that a neo-Hookean matrix with neo-Hookean fibres is representative of soft tissue. Under this assumption, a unit cell model is proposed to investigate the fibre-matrix interfacial stress field for biological soft tissue under biaxial loadings. In this unit cell model, the soft tissue is treated as a composite where the matrix is unidirectionally reinforced with a single family of aligned fibres. The results are compared with the model of Guo et al., which accounts for the fibre-matrix interfacial stress field, and Qiu and Pence's model, which does not proceed from the assumption that the fibres are themselves neo-Hookean. It is found that the stress representative of the fibre-matrix interface plays an important role in the deformation of the composite, and the model of Guo et al. underestimates this stress under large biaxial deformation. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: The paper presents a class‐AB flipped voltage follower (FVF) cell based on quasi‐floating gate and bulk‐driven techniques. The quasi‐floating gate technique is used to increase the current sinking capability, whereas the bulk‐driven technique is used to enhance the current sourcing capability by reducing the threshold voltage. Using these two techniques, the proposed class‐ AB FVF cell offers high current sinking and sourcing capabilities. Also, it provides high symmetrical slew rate without any additional circuitry. The physical layout of the proposed class‐ AB FVF cell has been designed in Cadence Virtuoso Layout XL editor using BSIM3v3 180‐nm CMOS technology, and post‐layout simulation results have been presented to validate its performance. The corner analysis of the proposed class‐ AB FVF cell has also been performed with temperature and supply voltage as design variables to show its performance under extreme conditions. [ABSTRACT FROM AUTHOR]

Cell volume regulation, as one of the fundamental homeostasis of the cell, is associated with many cellular behaviors and functions. With the increased studies on the effect of environmental mechanical cues on cell volume regulation, the relationship between cell volume regulation and mechanotransduction becomes more and more clear. In this paper, we review the mechanisms and hypotheses by which cell maintains its volume homeostasis both in vivo and in constructed cell mechanical microenvironment (CMM) in vitro. We discuss how the growth‐division regulation maintains the volume homeostasis of cells in the cell cycle and how the cell cortex/membrane tension mediates the effect of CMM (i.e., osmotic pressure, matrix stiffness, and mechanical force) on cell volume regulation. We also highlight the roles of cell volume as a perfect integrator of the downstream signals of mechanotransduction from different aspects of CMM and an effective indicator for the mechanical condition that cell confronts. This interdisciplinary perspective can provide new insight into biomechanics and may shed light on bioengineering and pathological research work. We hope this review can facilitate future studies on the investigation of the role of cell volume in mechanotransduction. [ABSTRACT FROM AUTHOR]

Introduction: Primary human papillomavirus (HPV) screening, testing for the virus responsible for 99% of cervical cancers, was introduced in 2018‐2020 in the UK. This was preceded by HPV triage of low‐grade cytology from 2012. Much of the evidence incorporated into current National Health Service (NHS) colposcopy guidance assessed outcomes prior to this change in screening. The aim of this paper is to assess adherence to NHS cervical screening programme standards, determine the incidence of cases reported as high‐risk HPV plus borderline nuclear change in endocervical cells, to calculate colposcopic accuracy and assess histological outcomes in this cohort. Method: A retrospective audit of women referred to a colposcopy clinic in one NHS trust from 2016 to 2018. Data relating to histological outcomes, cytological follow‐up and demographics were collected. Results: Of 2001 referrals, 22 data sets identifying HPV‐positive borderline endocervical change were eligible for analysis (1.2% incidence). Median age was 29.5. Two‐thirds (68.2%, n = 15) had high‐grade dysplasia at diagnostic biopsy. Those women with reassuring histology had normal cytological follow‐up. Colposcopic accuracy was moderate (positive predictive value 43.8%, negative predictive value 100%). Conclusions: Borderline nuclear change in endocervical cells is an uncommon condition but should be treated as a high‐grade referral. All women should be offered a diagnostic biopsy at the initial colposcopy; if no histopathological abnormality is identified, alternative sources of pathology should be considered. Excisional treatment should be recommended to unreliable attenders, those with a complete family and inadequate colposcopy (TZ3) and considered in younger women with a TZ3. [ABSTRACT FROM AUTHOR]

In this paper, the use of hp‐basis functions with higher differentiability properties is discussed in the context of the finite cell method and numerical simulations on complex geometries. For this purpose, Ckhp‐basis functions based on classical B‐splines and a new approach for the construction of C1hp‐basis functions with minimal local support are introduced. Both approaches allow for hanging nodes, whereas the new C1 approach also includes varying polynomial degrees. The properties of the hp‐basis functions are studied in several numerical experiments, in which a linear elastic problem with some singularities is discretized with adaptive refinements. Furthermore, the application of the Ckhp‐basis functions based on B‐splines is investigated in the context of nonlinear material models, namely hyperelasticity and elastoplasicity with finite strains. [ABSTRACT FROM AUTHOR]

The Triassic to Recent fossil record of the dinoflagellates is represented overwhelmingly by geologically resistant, organic‐walled, non‐motile resting cysts; such cysts are formed following the sexual phase in the life cycle. Very few confirmed records exist of the motile stage being preserved in the fossil record. This paper reports the occurrence of two very unusual dinoflagellate taphofacies, one developed in bituminous shales and the other in micrites, from the Oligocene fossil Lagerstätte at Sieblos, Hesse, Germany. A new dinoflagellate taxon, Sieblososphaera martini sp. nov. has been identified through analysis of dissociated skeletal elements in the bituminous shales and external moulds and casts in the micrites. The unique preservation of these fossils confirms them not only as primary biogenically silicified motile thecate cells, but also indicates that there was a much greater range of tabulation present within the subfamily Lithoperidiniaceae than has hitherto been recognized. [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]

Deinococcus geothermalis is resistant to chemical and physical stressors and forms tenuous biofilms in paper industry. The architecture of its biofilms growing on glass and on stainless acid proof steel was studied with confocal laser scanning microscopy and fluorescent lectins and nanobeads as in situ probes. Hydrophobic nanobeads adhered to the biofilms but did not penetrate to biofilm interior. In contrast, the biofilms were readily permeable towards many different lectins. A skeletal network of glycoconjugates, reactive with Dolichos biflorus and Maclura pomifera lectins, was prominent in the space inside the biofilm colony core but absent on the exterior. Cells in the core space of the biofilm were interconnected by a network of adhesion structures, reactive with Amaranthus caudatus lectin but with none of the 65 other tested lectins. The glycoconjugates connecting the individual cells to steel reacted with Phaseolus vulgaris lectin whereas those connecting to glass mainly reacted with A. caudatus lectin. Envelopes of all cells in the D. geothermalis biofilm reacted with several other lectins, with many different specificities. We conclude that numerous different glycoconjugates are involved in the adhesion and biofilm formation of D. geothermalis, possibly contributing its unique survival capacity when exposed to dehydration, biocidal chemicals and other extreme conditions. [ABSTRACT FROM AUTHOR]

The paper gives an overview of issues relating to the characterisation of the progressive collapse of core cellular materials used in sandwich construction. The specific structural application addressed is foreign object impact, and in this case the core cellular material is subject to multi-axial stresses, progressive collapse and possible rupture. The paper gives an overview of various theoretical and modelling issues, which are then related to experimental materials and structural tests for model development, calibration and validation. Most discussion concerns polymeric crushable foam, metal foam and metallic lattice structures. [ABSTRACT FROM AUTHOR]

Summary: Multiple degrees‐of‐freedom (multi‐DOF) cell orientation control is a vital important technique involved in single cell surgery applications. Currently, few studies have been performed toward automation of multi‐DOF cell orientation control using robotically controlled optical tweezers. In this paper, a robust control framework is developed to perform multi‐DOF cell rotational control with consideration of model uncertainties and external disturbances. Both simulation and experimental studies are presented to illustrate the performance of the proposed control strategy. The main contributions of this work lie in that this is the first time to develop a unified framework to achieve multi‐DOF cell orientation control without the need for accurate dynamic model parameters and/or any knowledge about uncertainty characteristic, which greatly enhances the robustness of the overall system. [ABSTRACT FROM AUTHOR]

The first paper in this series reported that it was possible to reconstitute the response of low concentrations of mouse spleen lymphocytes to concanavalin A (Con A) by adding small numbers of peritoneal exudate cells (PEC) to the cultures. In this paper it is shown that the role of the PEC in this system can be partially replaced by conditioned medium (CM) prepared from PEC cultures or completely replaced by CM taken from lymphocytes cultured at optimal concentration. These CM were inactive unless fresh Con A was added to the assay cultures. Activity was present in CM which was incubated with lymphocytes or PEC for the shortest possible time but maximal activity was found after 24 hr of incubation. Activity was also found in CM prepared in the absence of Con A. Only in the case of lymphocytes cultured at optimal concentration for 24 hr was there substantially more activity in the CM thus prepared if Con A was present. PEC preparations depleted of T lymphocytes produced as much activity in CM as the untreated control. CM produced by PEC was less sensitive to heat treatment or to freezing and thawing than that produced by lymphocyte cultures. [ABSTRACT FROM AUTHOR]

Over the past three decades, many contributions have been made to the development of a mathematical basis for describing water transport in plant cells and tissue. This review paper attempts to summarize the more significant contributions and to outline the concepts upon which the various mathematical analyses are founded. The paper itself is divided into three major sections. Section I deals with the quantitative water relations of single plant cells. Basic equations are developed which describe the water statics and water dynamics of such cells. Included is a discussion of the theory and methods for measuring the various parameters (permeabilities, cell wall elastic moduli, etc.) which enter into the development. The section closes with a presentation of circuit analog models for single plant cells. Section Il is devoted to a review and development of the water relations of plant tissues which contain numerous cells in series. Following a historical overview, various existing models are derived and physical tissue properties which enter the derivation are identified. The concept of 'local equilibrium' is discussed and circuit analog models for single cells are generalized and applied to several cells in series. The final section contains two example applications of water transport theory as it applies to plant tissue. One application involves radial water movement in a soybean hypocotyl while the other deals with water transport in a growing root tip. A summary at the end of the section is largely devoted to a discussion of the limitations of mathematical models that are presently available. [ABSTRACT FROM AUTHOR]

In the renewable energy scenario, energy storage is of essence. In this context, power‐to‐liquid (PtL) and power‐to‐gas (PtG) concepts have attracted large attention, where the use of solid oxide electrolysis cells (SOECs) has a huge potential, due to their high conversion efficiencies. However, performance and durability of these cells still need to be improved for a large‐scale commercialization of the SOEC technology. It is often difficult to identify the various loss and degradation mechanisms limiting the cell performance and durability. This paper contributes to this scientific discussion, by providing a careful analysis of the degradation mechanisms occurring in three different cells during long‐term H2O and CO2 co‐electrolysis, at 1,200 mV. Electrochemical impedance spectroscopy (EIS) is measured before, during and after the electrolysis operation, and is utilized to address the individual electrode degradation mechanisms and the development of leaks through the electrolyte. Moreover, the leak rates under open circuit voltage (OCV) measurements were compared. In addition, microstructural analysis of the electrodes and electrolytes is related to the electrochemical findings to contribute to the discussion on the interdependency of the degradation mechanisms. [ABSTRACT FROM AUTHOR]

This paper presents the numerical and experimental results of a miniaturized half‐mode substrate integrated waveguide HMSIW C‐band pass filter with defected ground structure DGS, using two slots and dumbbell shape defected ground structure. These two slots which are etched on the upper plane of the SIW cavity are used to constitute a multiple‐mode resonator, and the dumbbell‐shape fractal DGS etched on the bottom plane can considerably enhance the filter's performances. The manufactured band‐pass filter in half mode based on SIW technology has a size nearly half of that of a normal filter. The measurements results obtained by CST in C‐band show that the manufactured filter has a large transmitted bandwidth of about 1.53 GHz from 5.97 to 7.5 GHz. The higher measured insertion is about −2.6 dB and the lower return loss measured is about −34 dB. The size of filter design achieved is 7.48 × 38.12 mm2 which make it the more compact in comparison with some published works at the C‐band frequency. [ABSTRACT FROM AUTHOR]

Multi‐junction cells can significantly improve the energy yield of photovoltaic systems over a single‐junction cell. The internal interconnection scheme of the subcells is an important aspect in determining the resulting levelized cost of electricity. For a dual‐junction cell, two approaches are commonly discussed: series‐connected tandem cells with two terminals or independently working subcells in a four‐terminal (4T) tandem device. In this paper, we explore the working principle and the operation modes of a third, rarely discussed option: a three‐terminal (3T) tandem cell using a back‐contacted bottom cell with 3Ts. We use current–voltage measurements of illuminated 3T interdigitated back contact cells and confirm that the front and rear base contacts are at similar quasi‐Fermi level positions, which enables the bottom cell to either efficiently collect surplus carriers, in the case of a current‐limiting or carrier injecting top cell, or inject majority carriers, in the case of a current‐limiting bottom cell. As a result, no current matching is needed. The power output of an idealized 3T bottom cell without resistive effects is independent of the current density applied from the top cell. These characteristics of the 3T bottom cells enable a 3T tandem to operate as efficiently as a 4T tandem, while being compatible with monolithic design and not requiring intermediate grids. We propose a simple equivalent circuit model including additional resistive effects, which describes a real 3T bottom cell and achieves excellent agreement to the experiment. We deduce design guidelines for a 3T bottom cell in different operation regimes. We explore the working principle and operation modes of a back‐contacted bottom cell with three terminals (3Ts) for tandem application. Since the third terminal enables efficient collection and injection of majority carriers, current matching in a 3T tandem is superfluous, and the power output of a 3T bottom cell is mostly independent of the current applied from the top cell. A monolithic 3T tandem is predicted to operate as efficiently as a four‐terminal tandem. [ABSTRACT FROM AUTHOR]

Earlier investigations have shown that potassium emerges from the yeast cell when the latter is shaken in a NaF solution. The potassium emergence seems to be caused by changed electrostatic conditions in the cell. Fluoride penetrates into the cell in the form of undissociated hydrogen fluoride. In the cell HF dissociates to a large extent into fluoride and hydrogen ions. The more acid the solution surrounding the cells is the more hydrogen ions can be carried into the cells in this way. In an earlier paper, calculations showed that the pH in the cell can hereby be decreased considerably. The changed pH in the cell will surely influence the activity of the enzymes. As a result, non diffusible anions could be transformed to diffusible ones. In this way potassium, originally electrostatically attracted to non-diffusible anions, is set free and can leave the cell. If the hydrogen ions were responsible for the potassium emergence, one would expect that other weak acids would also cause a potassium loss from the cell, that is, acids which are able to penetrate into the cell and which are not attacked by the enzymes of the cell. The aim of the present work was to examine the influence of a number of weak acids on the potassium management of the cell. The following weak acids were examined: formic, acetic, propionic. butyric. isobutyric, lactic, β-hydroxy-butyric, succinic, tartaric and citric acid. The experiments showed that the permeation ability alone of the weak acids is not decisive for a potassium emergence. It was considered if the dissociation constant of the weak acids was decisive for the potassium emergence. It appeared that only those acids, whose dissociation constant are about 10-4 cause a distinct potassium emergence. Acids with a dissociation constant about 10-5 seem already to be too weak. An increase in the concentration of these can, nevertheless, promote a potassium emergence. Independent of each other dr. H. Ussing and later professor E. J. Conway drew the author's attention to the possibility that potassium could perhaps leave the cell together with fluoride or formate ions as an ion pair. The size of the anions of the other acids, on the contrary, does not permit a permeation, and therefore causes no potassium emergence. Investigations on this subject will be presented in a coming paper. [ABSTRACT FROM AUTHOR]

Mechanical force is known to influence the behavior of biological cells. To study how external mechanical forces may affect cellular response and function necessitates the development of sophisticated force-control techniques for accurate application of dynamical forces on living cells. In this paper, we develop a robust force control algorithm that enables accurate application of an external force on a dynamics model of biological cells. Such force control is achieved by utilizing a six-strut cellular tensegrity model constructed based on the structural approach. Leveraging on the more comprehensive description of the nonlinearity and dynamic coupling of internal structural elements provided by this tensegrity model, we synthesize a novel robust control law that can effectively deal with model uncertainties and partial state measurability. Numerical simulations (involving forces of different dynamics profiles) are conducted to demonstrate the effectiveness of the proposal force control algorithm. [ABSTRACT FROM AUTHOR]

This study describes a case of primary myoepithelial carcinoma of the skin and reviews the available literature on this topic. Myoepitheliomas and carcinomas arise most frequently from myoepithelial cells within the salivary glands but are found in many anatomical locations. We documented a case of an 80-year-old man with a 2 × 2 × 1 cm tumour located on the scalp. This tumour emerged over a period of 2 months. The tumour was radically excised, and histological examination revealed a cutaneous myoepithelial carcinoma. At an 18-month follow-up, no recurrence of the tumour was found. A systematic literature search identified 23 papers that reported 58 cases of cutaneous myoepitheliomas and myoepithelial carcinomas. All cases are reviewed in the presented paper. This case report and literature review serves to increase awareness regarding myoepithelial carcinomas. These tumours exhibit high metastatic potential, and it is thus very important to perform radical surgery. [ABSTRACT FROM AUTHOR]

Microglia, the brain's tissue‐resident macrophages, contribute to the developmental elimination of extranumerary synapses and to pathologic synapse loss in mouse models of neurodegeneration. Two papers published in The EMBO Journal reveal that phosphatidylserine (PS) is a neuronal cue for microglial synapse elimination. [ABSTRACT FROM AUTHOR]

Abstract: IgE and not IgG is usually associated with allergy. IgE lodged on mast cells in skin or gut and basophils in the blood allows for the prolonged duration of allergy through the persistent expression of high affinity IgE receptors. However, many allergic reactions are not dependent on IgE and are generated in the absence of allergen specific and even total IgE. Instead, IgG plasma cells are involved in induction of, and for much of the pathogenesis of, allergic diseases. The pattern of IgG producing plasma cells in atopic children and the tendency for direct or further class switching to IgE are the principle factors responsible for long‐lasting sensitization of mast cells in allergic children. Indirect class switching from IgG producing plasma cells has been shown to be the predominant pathway for production of IgE while a Th2 microenvironment, genetic predisposition, and the concentration and nature of allergens together act on IgG plasma cells in the atopic tendency to undergo further immunoglobulin gene recombination. The seminal involvement of IgG in allergy is further indicated by the principal role of IgG4 in the natural resolution of allergy and as the favourable immunological response to immunotherapy. This paper will look at allergy through the role of different antibodies than IgE and give current knowledge of the nature and role of IgG antibodies in the start, maintenance and resolution of allergy. [ABSTRACT FROM AUTHOR]

Electrogenic cells such as cardiomyocytes and neurons rely mainly on electrical signals for intercellular communication. Microelectrode arrays (MEAs) have been developed for long-term recording of cell signals and stimulation of electrogenic cells under low-cell-stress conditions, providing new insights in the behavior of electrogenic cells and the operation of the brain. To date, MEAs are relying on flat or needle-shaped electrode surfaces, mainly due to limitations in the lithographic processes. This paper relies on a previously reported elasto-capillary aggregation process to create 3D carbon nanotube (CNT) MEAs. This study shows that CNTs aggregate in well-shaped structures of similar size as cardiomyocytes are particularly interesting for MEA applications. This is because i) CNT microwells of the right diameter preferentially trap individual cardiomyocytes, which facilitates single cell recording without the need for clamping cells or signal deconvolution, and ii) once the cells are trapped inside of the CNT wells, this 3D CNT structure is used as an electrode surrounding the cell, which increases the cell-electrode contact area. As a result, this study finds that the recorded output voltages increase significantly (more than 200%). This fabrication process paves the way for future study of complex interactions between electrogenic cells and 3D recording electrodes. [ABSTRACT FROM AUTHOR]

Summary With the rapid rise in our knowledge about the structural and functional properties of neuronal microcircuits and the exponentially increasing power of computers, it has become possible to closely integrate experimental findings with large-scale, anatomically and biophysically realistic computational simulations of control and epileptic neuronal networks with unprecedented precision and predictive power. In this paper, we discuss the biological basis of model development, and outline specific applications, including exciting new computational and experimental results concerning the roles of aberrant hyperconnected hub-like neurons in seizures. [ABSTRACT FROM AUTHOR]

Protein-protein interactions (PPIs) are vitally important for every process in a living cell. Information about these interactions can improve our understanding of diseases and provide the basis to revolutionize therapeutic treatments. However, since PPIs are involved with extremely complicated biological processes, it is necessary to develop novel tools to deal with this kind of network systems. To realize this, a bio-entity network approach is introduced to show the topology structure of dynamic and collective performances of PPI networks and analyze the variance of the protein node that plays an important role in the PPI network. Also, spectrum analysis is used to capture the discrete and stochastic feature of PPIs. The yeast protein interaction network is considered as a paradigm. It is demonstrated that the proposed approach can easily and clearly identify the hub-proteins that have the most impact on the PPI system concerned. It is expected that the bio-entity network approach as presented in this paper might become a useful tool in system biology. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [ABSTRACT FROM AUTHOR]

Successful encapsulation of cells is of interest for a wide variety of biotechnological applications such as microbial fuel cells (MFCs), food systems, environmental remediation, fermentation reactors, and regenerative medicine. In this review paper, biohybrid materials comprised of encapsulated cells in electrospun polymer fibers are presented. Such bio-encapsulation allows for the protection of cells from harsh environments as well as the control of the physico-mechanical properties in the cell's immediate surroundings, i.e. the chemical structure and permeability of the matrix as well as its density. This review paper discusses the preparation methods of these 'living materials' and their potential applications using examples of the encapsulation of bacterial cells in various electrospun fibers which can be monolithic, core-shell, or hollow. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Please cite this paper as: The mesenchymal component of hair follicle neogenesis: background, methods and molecular characterization. Experimental Dermatology 2010; 19: 89–99. Hair follicle morphogenesis and regeneration occur by an extensive and collaborative crosstalk between epithelial and mesenchymal skin components. A series of pioneering studies, which revealed an indispensable role of follicular dermal papilla and dermal sheath cells in this crosstalk, has led workers in the field to study in detail the anatomical distribution, functional properties, and molecular signature of the trichogenic dermal cells. The purpose of this paper was to provide a practical summary of the development and recent advances in the study of trichogenic dermal cells. Following a short review of the relevant literature, the methods for isolating and culturing these cells are summarized. Next, the bioassays, both in vivo and in vitro, that enable the evaluation of trichogenic properties of tested dermal cells are described in detail. A list of trichogenic molecular markers identified by those assays is also provided. Finally, this methods review is completed by defining some of the major questions needing resolution. [ABSTRACT FROM AUTHOR]

In this paper, we review some published studies using correlative light and electron microscopy methods. We further refined our criteria to include only those studies using live cells for light microscope and where high-pressure freezing was the method of specimen preparation for electron microscopy. High-pressure freezing is especially important for some difficult-to-fix samples, and for optimal preservation of ultrastructure in samples larger than a few micrometres. How the light microscope observations are done is completely sample dependent, but the choice of high-pressure freezer depends on the speed required to capture (freeze) the biological event of interest. For events requiring high time resolution (in the 4–5 s range) the Leica EM PACT2 with rapid transfer system works well. For correlative work on structures of interest that are either non-motile or moving slowly (minutes rather than seconds), any make of high-pressure freezer will work. We also report on some efforts to improve the capabilities of the Leica EM PACT2 rapid transfer system. [ABSTRACT FROM AUTHOR]

Recently, micro-rotation confocal microscopy has enabled the acquisition of a sequence of micro-rotated images of nonadherent living cells obtained during a partially controlled rotation movement of the cell through the focal plane. Although we are now able to estimate the three-dimensional position of every optical section with respect to the cell frame, the reconstruction of the cell from the positioned micro-rotated images remains a last task that this paper addresses. This is not strictly an interpolation problem since a micro-rotated image is a convoluted two-dimensional map of a three-dimensional reality. It is rather a ‘reconstruction from projection’ problem where the term projection is associated to the PSF of the deconvolution process. Micro-rotation microscopy has a specific difficulty. It does not yield a complete coverage of the volume. In this paper, experiments illustrate the ability of the classical EM algorithm to deconvolve efficiently cell volume despite of the incomplete coverage. This cell reconstruction method is compared to a kernel-based method of interpolation, which does not take account explicitly the point-spread-function (PSF). It is also compared to the standard volume obtained from a conventional z-stack. Our results suggest that deconvolution of micro-rotation image series opens some exciting new avenues for further analysis, ultimately laying the way towards establishing an enhanced resolution 3D light microscopy. [ABSTRACT FROM AUTHOR]

This paper outlines prospects for applying the emerging techniques of synthetic biology to the field of anatomy, with the aim of programming cells to organize themselves into specific, novel arrangements, structures and tissues. There are two main reasons why developing this hybrid discipline – synthetic morphology – would be useful. The first is that having a way to engineer self-constructing assemblies of cells would provide a powerful means of tissue engineering for clinical use in surgery and regenerative medicine. The second is that construction of simple novel systems according to theories of morphogenesis gained from study of real embryos will provide a means of testing those theories rigorously, something that is very difficult to do by manipulation of complex embryos. This paper sets out the engineering requirements for synthetic morphology, which include the development of a library of sensor modules, regulatory modules and effector modules that can be connected functionally within cells. A substantial number of sensor and regulatory modules already exist and this paper argues that some potential effector modules have already been identified. The necessary library may therefore be within reach. The paper ends by suggesting a set of challenges, ranging from simple to complex, the achievement of which would provide valuable proofs of concept. [ABSTRACT FROM AUTHOR]

The article discusses the epigenetics influence on cell determination in early mouse embryo development. This paper features recent researches showing evidences on epigenetic information on histone arginine methylation mediated by CARM1 which contributes to the cell fate decisions in mouse four-cell-stage embryo.