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https://www.readbyqxmd.com/read/28449118/polyphosphate-accumulating-bacterial-community-colonizing-the-calcium-bodies-of-terrestrial-isopod-crustaceans-titanethes-albus-and-hyloniscus-riparius
#1
Rok Kostanjšek, Vittori Miloš, Vesna Srot, Peter A van Aken, Štrus Jasna
Terrestrial isopods from the group Trichoniscidae accumulate calcium in specialized organs, known as the calcium bodies. These consist of two pairs of epithelial sacs located alongside the digestive system. These organs contain various forms of calcium and constantly present bacteria. To elucidate their origin and role, we analyzed the bacteria of the calcium bodies in the cave-dwelling isopod Titanethes albus and the epigean species Hyloniscus riparius, by microscopy, histochemistry, energy dispersive X-ray spectrometry, 16S rRNA analysis and in situ hybridization...
April 25, 2017: FEMS Microbiology Ecology
https://www.readbyqxmd.com/read/28448927/time-varying-sensitivity-analysis-of-hydrologic-and-sediment-parameters-at-multiple-timescales-implications-for-conservation-practices
#2
Hui Xie, Zhenyao Shen, Lei Chen, Jiali Qiu, Jianwei Dong
Environmental models can be used to better understand the hydrologic and sediment behavior in a watershed system. However, different processes may dominate at different time periods and timescales, which highly complicate the model interpretation. The related parameter uncertainty may be significant and needs to be addressed to avoid bias in the watershed management. In this study, we used the time-varying and multi-timescale (TVMT) method to characterize the temporal dynamics of parameter sensitivity at different timescales in hydrologic and sediment modeling...
April 24, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28448716/phosphorylation-weakens-but-does-not-inhibit-membrane-binding-and-clustering-of-k-ras4b
#3
Si-Yu Zhang, Benjamin Sperlich, Fang-Yi Li, Samy Al-Ayoubi, Hong-Xue Chen, YuFen Zhao, Yan-Mei Li, Katrin Weise, Roland Winter, Yong-Xiang Chen
K-Ras4B is one of the most frequently mutated Ras isoforms in cancers. The signaling activity of K-Ras4B depends on its localization to the plasma membrane (PM), which is mainly mediated by its polybasic farnesylated C-terminus. On top of the constitutive cycles that maintain the PM enrichment of K-Ras4B, conditional phosphorylation at Ser181 located within this motif has been found to be involved in regulating K-Ras4B's cell distribution and signaling activity. However, discordant observations have undermined our understanding of the role this phosphorylation plays...
April 27, 2017: ACS Chemical Biology
https://www.readbyqxmd.com/read/28448638/a-minimal-model-of-burst-noise-induced-bistability
#4
Johannes Falk, Marc Mendler, Barbara Drossel
We investigate the influence of intrinsic noise on stable states of a one-dimensional dynamical system that shows in its deterministic version a saddle-node bifurcation between monostable and bistable behaviour. The system is a modified version of the Schlögl model, which is a chemical reaction system with only one type of molecule. The strength of the intrinsic noise is varied without changing the deterministic description by introducing bursts in the autocatalytic production step. We study the transitions between monostable and bistable behavior in this system by evaluating the number of maxima of the stationary probability distribution...
2017: PloS One
https://www.readbyqxmd.com/read/28448599/simulation-of-the-dynamics-of-primary-immunodeficiencies-in-cd4-t-cells
#5
Gabriel N Teku, Mauno Vihinen
Primary immunodeficiencies (PIDs) form a large and heterogeneous group of mainly rare disorders that affect the immune system. T-cell deficiencies account for about one-tenth of PIDs, most of them being monogenic. Apart from genetic and clinical information, lots of other data are available for PID proteins and genes, including functions and interactions. Thus, it is possible to perform systems biology studies on the effects of PIDs on T-cell physiology and response. To achieve this, we reconstructed a T-cell network model based on literature mining and TPPIN, a previously published core T-cell network, and performed semi-quantitative dynamic network simulations on both normal and T-cell PID failure modes...
2017: PloS One
https://www.readbyqxmd.com/read/28448490/the-value-of-daily-platelet-counts-for-predicting-dengue-shock-syndrome-results-from-a-prospective-observational-study-of-2301-vietnamese-children-with-dengue
#6
Phung Khanh Lam, Tran Van Ngoc, Truong Thi Thu Thuy, Nguyen Thi Hong Van, Tran Thi Nhu Thuy, Dong Thi Hoai Tam, Nguyen Minh Dung, Nguyen Thi Hanh Tien, Nguyen Tan Thanh Kieu, Cameron Simmons, Bridget Wills, Marcel Wolbers
BACKGROUND: Dengue is the most important mosquito-borne viral infection to affect humans. Although it usually manifests as a self-limited febrile illness, complications may occur as the fever subsides. A systemic vascular leak syndrome that sometimes progresses to life-threatening hypovolaemic shock is the most serious complication seen in children, typically accompanied by haemoconcentration and thrombocytopenia. Robust evidence on risk factors, especially features present early in the illness course, for progression to dengue shock syndrome (DSS) is lacking...
April 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/28448451/time-aware-service-ranking-prediction-in-the-internet-of-things-environment
#7
Yuze Huang, Jiwei Huang, Bo Cheng, Shuqing He, Junliang Chen
With the rapid development of the Internet of things (IoT), building IoT systems with high quality of service (QoS) has become an urgent requirement in both academia and industry. During the procedures of building IoT systems, QoS-aware service selection is an important concern, which requires the ranking of a set of functionally similar services according to their QoS values. In reality, however, it is quite expensive and even impractical to evaluate all geographically-dispersed IoT services at a single client to obtain such a ranking...
April 27, 2017: Sensors
https://www.readbyqxmd.com/read/28448404/dynamic-contrast-enhanced-magnetic-resonance-imaging-of-ocular-melanoma-as-a-tool-to-predict-metastatic-potential
#8
Wenbo Wei, Guang Jia, Hendrik von Tengg-Kobligk, Johannes T Heverhagen, Mohamed Abdel-Rahman, Lai Wei, John B Christoforidis, Frederick Davidorf, Michael V Knopp
PURPOSE: This study explores the capability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to differentiate tumor characteristics of metastatic and nonmetastatic choroidal melanoma as a potential tool for patient management. MATERIALS AND METHODS: A total of 13 patients (69 ± 9 years) with choroidal melanoma were imaged using DCE-MRI on a 3-T MRI system with a 16-channel head coil. The Tofts 2-compartment model was chosen for quantification, and parameters K (the transfer constant from the blood plasma to the extracellular space) and Kep (the transfer constant from the extracellular space to the blood plasma) were calculated and compared...
April 26, 2017: Journal of Computer Assisted Tomography
https://www.readbyqxmd.com/read/28448270/a-new-in-vitro-spine-test-rig-to-track-multiple-vertebral-motions-under-physiological-conditions
#9
Agnes Beckmann, Christian Herren, Marion Mundt, Jan Siewe, Philipp Kobbe, Rolf Sobottke, Hans-Christoph Pape, Marcus Stoffel, Bernd Markert
In vitro pure moment spine tests are commonly used to analyse surgical implants in cadaveric models. Most of the tests are performed at room temperature. However, some new dynamic instrumentation devices and soft tissues show temperature-dependent material properties. Therefore, the aim of this study is to develop a new test rig, which allows applying pure moments on lumbar spine specimens in a vapour-filled chamber at body temperature. As no direct sight is given in the vapour-filled closed chamber, a magnetic tracking (MT) system with implantable receivers was used...
April 27, 2017: Biomedizinische Technik. Biomedical Engineering
https://www.readbyqxmd.com/read/28447851/-understanding-the-role-of-speech-production-in-reading-evidence-for-a-print-to-speech-neural-network-using-graphical-analysis-correction-to-cummine-et-al-2016
#10
(no author information available yet)
Reports an error in "Understanding the role of speech production in reading: Evidence for a print-to-speech neural network using graphical analysis" by Jacqueline Cummine, Ivor Cribben, Connie Luu, Esther Kim, Reyhaneh Bahktiari, George Georgiou and Carol A. Boliek (Neuropsychology, 2016[May], Vol 30[4], 385-397). In the article, the fifth author's name [Bakhtiari] was misspelled. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2015-49069-001...
May 2017: Neuropsychology
https://www.readbyqxmd.com/read/28447639/frequency-of-extreme-sahelian-storms-tripled-since-1982-in-satellite-observations
#11
Christopher M Taylor, Danijel Belušić, Françoise Guichard, Douglas J Parker, Théo Vischel, Olivier Bock, Phil P Harris, Serge Janicot, Cornelia Klein, Gérémy Panthou
The hydrological cycle is expected to intensify under global warming, with studies reporting more frequent extreme rain events in many regions of the world, and predicting increases in future flood frequency. Such early, predominantly mid-latitude observations are essential because of shortcomings within climate models in their depiction of convective rainfall. A globally important group of intense storms-mesoscale convective systems (MCSs)-poses a particular challenge, because they organize dynamically on spatial scales that cannot be resolved by conventional climate models...
April 26, 2017: Nature
https://www.readbyqxmd.com/read/28447364/the-ja-and-aba-signaling-pathways-crosstalk-during-one-but-not-repeated-dehydration-stresses-a-non-specific-panicky-or-a-meaningful-response
#12
Zoya Avramova
Experiencing diverse and recurring biotic and abiotic stresses throughout life, plants have evolved mechanisms to respond, survive and, eventually, adapt to changing habitats. The initial response to drought involves a large number of genes that are involved also in response to other stresses. According to current models, this initial response is non-specific, becoming stress-specific only at later time points. The question, then, is whether non-specific activation of various stress-signaling systems leading to the expression of numerous stresses-regulated genes is a false-alarm ('panicky') response or whether it has biologically relevant consequences for the plant...
April 26, 2017: Plant, Cell & Environment
https://www.readbyqxmd.com/read/28447346/a-charge-equilibration-formalism-for-treating-charge-transfer-effects-in-md-simulations-application-to-water-clusters
#13
Sudipta Kumar Sinha, Mohit Mehta, Sandeep Patel
Conventional classical force fields by construction do not explicitly partition intermolecular interactions to include polarization and charge transfer effects, whereas fully quantum mechanical treatments allow a means to effect this dissection (although not uniquely due to the lack of a charge transfer operator). Considering the importance of polarization in a variety of systems, a particular class of classical models, charge equilibration models, have been extensively developed to study those systems; since these types of interaction models are inherently based on movement of charge throughout a system, they are natural platform for including polarization and charge transfer effects within the context of molecular simulations...
June 15, 2017: Journal of Computational Chemistry
https://www.readbyqxmd.com/read/28446944/protective-effects-of-proline-rich-peptide-in-a-rat-model-of-alzheimer-disease-an-electrophysiological-study
#14
Naser Khalaji, John Sarkissian, Vergine Chavushyan, Vaghinak Sarkisian
INTRODUCTION: Alzheimer disease (AD) is the most common form of dementia in the elderly that slowly destroys memory and cognitive functions. The disease has no cure and leads to significant structural and functional brain abnormalities. To facilitate the treatment of this disease, we aimed to investigate proline-rich peptide (PRP-1) action of hypothalamus on hippocampal (HP) neurons and dynamics of their recovery, after intracerebroventricular (ICV) injection of amyloid-β (Aβ). METHODS: Experiments were carried out on 24 adult, male Albino rats (average weight: 230±30 g)...
January 2017: Basic and Clinical Neuroscience
https://www.readbyqxmd.com/read/28446878/computational-model-predicts-the-effects-of-targeting-cellular-metabolism-in-pancreatic-cancer
#15
Mahua Roy, Stacey D Finley
Reprogramming of energy metabolism is a hallmark of cancer that enables the cancer cells to meet the increased energetic requirements due to uncontrolled proliferation. One prominent example is pancreatic ductal adenocarcinoma, an aggressive form of cancer with an overall 5-year survival rate of 5%. The reprogramming mechanism in pancreatic cancer involves deregulated uptake of glucose and glutamine and other opportunistic modes of satisfying energetic demands in a hypoxic and nutrient-poor environment. In the current study, we apply systems biology approaches to enable a better understanding of the dynamics of the distinct metabolic alterations in KRAS-mediated pancreatic cancer, with the goal of impeding early cell proliferation by identifying the optimal metabolic enzymes to target...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28446583/a-shared-neural-integrator-for-human-posture-control
#16
Stephanie E Haggerty, Amy R Wu, Kathleen H Sienko, Arthur D Kuo
Control of standing posture requires fusion of multiple inputs including visual, vestibular, somatosensory, and other sensors, each having distinct dynamics. The semicircular canals, for example, have a high-pass filter response to angular velocity, quickly sensing a step change in head rotational velocity followed by a decay. To stabilize gaze despite this decay, the central nervous system supplies a neural "velocity storage" integrator, a filter that extends the angular velocity signal. Similar filtering might contribute temporal dynamics to posture control, as suggested by some state estimation models...
April 26, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28446174/a-scalable-metabolite-supplementation-strategy-against-antibiotic-resistant-pathogen-chromobacterium-violaceum-induced-by-nad-nadh-imbalance
#17
Deepanwita Banerjee, Dharmeshkumar Parmar, Nivedita Bhattacharya, Avinash D Ghanate, Venkateswarlu Panchagnula, Anu Raghunathan
BACKGROUND: The leading edge of the global problem of antibiotic resistance necessitates novel therapeutic strategies. This study develops a novel systems biology driven approach for killing antibiotic resistant pathogens using benign metabolites. RESULTS: Controlled laboratory evolutions established chloramphenicol and streptomycin resistant pathogens of Chromobacterium. These resistant pathogens showed higher growth rates and required higher lethal doses of antibiotic...
April 26, 2017: BMC Systems Biology
https://www.readbyqxmd.com/read/28446064/variability-of-energy-input-into-selected-subsystems-of-the-human-glove-tool-system-a-theoretical-study
#18
Tomasz Hermann, Marian Witalis Dobry
The article presents an application of the energy method to assess the energy input introduced into two subsystems of the human-glove-tool system. To achieve this aim, a physical model of the system was developed. It consists of dynamic models of the human body and the glove described in the Standard No. ISO 10068:2012, and a model of a hand-held power tool. The energy input introduced into the subsystems, i.e., the human body and the glove, was analysed in the domain of energy and involved calculating three component energy inputs of forces...
April 27, 2017: International Journal of Occupational Safety and Ergonomics: JOSE
https://www.readbyqxmd.com/read/28445999/crystal-orientation-effect-on-the-subsurface-deformation-of-monocrystalline-germanium-in-nanometric-cutting
#19
Min Lai, Xiaodong Zhang, Fengzhou Fang
Molecular dynamics simulations of nanometric cutting on monocrystalline germanium are conducted to investigate the subsurface deformation during and after nanometric cutting. The continuous random network model of amorphous germanium is established by molecular dynamics simulation, and its characteristic parameters are extracted to compare with those of the machined deformed layer. The coordination number distribution and radial distribution function (RDF) show that the machined surface presents the similar amorphous state...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28445762/analysis-of-active-transport-by-fluorescence-recovery-after-photobleaching
#20
Maria-Veronica Ciocanel, Jill A Kreiling, James A Gagnon, Kimberly L Mowry, Björn Sandstede
Fluorescence recovery after photobleaching (FRAP) is a well-established experimental technique to study binding and diffusion of molecules in cells. Although a large number of analytical and numerical models have been developed to extract binding and diffusion rates from FRAP recovery curves, active transport of molecules is typically not included in the existing models that are used to estimate these rates. Here we present a validated numerical method for estimating diffusion, binding/unbinding rates, and active transport velocities using FRAP data that captures intracellular dynamics through partial differential equation models...
April 25, 2017: Biophysical Journal
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