Read by QxMD icon Read

Complex networks

Maryam Songhorzadeh, Karim Ansari-Asl, Alimorad Mahmoudi
Quantifying delayed directional couplings between electroencephalographic (EEG) time series requires an efficient method of causal network inference. This is especially due to the limited knowledge about the underlying dynamics of the brain activity. Recent methods based on information theoretic measures such as Transfer Entropy (TE) made significant progress on this issue by providing a model-free framework for causality detection. However, TE estimation from observed data is not a trivial task, especially when the number of variables is large which is the case in a highly complex system like human brain...
October 14, 2016: Computers in Biology and Medicine
Andrew S Hwang, Steven J Atlas, Johan Hong, Jeffrey M Ashburner, Adrian H Zai, Richard W Grant, Clemens S Hong
BACKGROUND: A better understanding of the attributes of patients who require more effort to manage may improve risk adjustment approaches and lead to more efficient resource allocation, improved patient care and health outcomes, and reduced burnout in primary care clinicians. OBJECTIVE: To identify and characterize high-effort patients from the physician's perspective. DESIGN: Cohort study. PARTICIPANTS: Ninety-nine primary care physicians in an academic primary care network...
October 21, 2016: Journal of General Internal Medicine
Jong Wha J Joo, Eun Yong Kang, Elin Org, Nick Furlotte, Brian Parks, Farhad Hormozdiari, Aldons J Lusis, Eleazar Eskin
A typical GWAS tests correlation between a single phenotype and each genotype one at a time. However, single phenotype analysis might miss unmeasured aspects of complex biological networks. Analyzing many phenotypes simultaneously may increase the power to capture these unmeasured aspects and detect more variants. Several multivariate approaches aim to detect variants related to more than one phenotype, but these current approaches do not consider the effects of population structure. As a result, these approaches may result in a significant amount of false positive identifications...
October 21, 2016: Genetics
Thomas D Loreng, Elizabeth F Smith
The motile cilium is a complex organelle that is typically comprised of a 9+2 microtubule skeleton; nine doublet microtubules surrounding a pair of central singlet microtubules. Like the doublet microtubules, the central microtubules form a scaffold for the assembly of protein complexes forming an intricate network of interconnected projections. The central microtubules and associated structures are collectively referred to as the central apparatus (CA). Studies using a variety of experimental approaches and model organisms have led to the discovery of a number of highly conserved protein complexes, unprecedented high-resolution views of projection structure, and new insights into regulation of dynein-driven microtubule sliding...
October 21, 2016: Cold Spring Harbor Perspectives in Biology
Hung-Yi Liu, Tanja Greene, Tsai-Yu Lin, Camron S Dawes, Murray Korc, Chien-Chi Lin
: The complex network of biochemical and biophysical cues in the pancreatic desmoplasia not only presents challenges to the fundamental understanding of tumor progression, but also hinders the development of therapeutic strategies against pancreatic cancer. Residing in the desmoplasia, pancreatic stellate cells (PSCs) are the major stromal cells affecting the growth and metastasis of pancreatic cancer cells by means of paracrine effects and extracellular matrix protein deposition. PSCs remain in a quiescent/dormant state until they are 'activated' by various environmental cues...
October 18, 2016: Acta Biomaterialia
Alexander Lück, Verena Wolf
BACKGROUND: Discrete-state stochastic models have become a well-established approach to describe biochemical reaction networks that are influenced by the inherent randomness of cellular events. In the last years several methods for accurately approximating the statistical moments of such models have become very popular since they allow an efficient analysis of complex networks. RESULTS: We propose a generalized method of moments approach for inferring the parameters of reaction networks based on a sophisticated matching of the statistical moments of the corresponding stochastic model and the sample moments of population snapshot data...
October 21, 2016: BMC Systems Biology
Travis L Goron, Manish N Raizada
BACKGROUND: The amino acid glutamine (Gln) is a primary transport form of nitrogen in vasculature following root uptake, critical for the location/timing of growth in maize and other cereals. Analytical chemistry methods do not permit in situ analysis of Gln, including visualization within the vascular network. Their cost and tissue requirement are barriers to exploring the complexity of Gln dynamics. We previously reported a biosensor, GlnLux, which can measure relative Gln levels inexpensively with tiny amounts of tissue...
October 21, 2016: BMC Plant Biology
Guangquan Lu, Ying Xiong, Chuan Ding, Yunpeng Wang
The schedule of urban road network recovery caused by rainstorms, snow, and other bad weather conditions, traffic incidents, and other daily events is essential. However, limited studies have been conducted to investigate this problem. We fill this research gap by proposing an optimal schedule for urban road network repair with limited repair resources based on the greedy algorithm. Critical links will be given priority in repair according to the basic concept of the greedy algorithm. In this study, the link whose restoration produces the ratio of the system-wide travel time of the current network to the worst network is the minimum...
2016: PloS One
Feifei Xiao, Guoshuai Cai, Heping Zhang
In early 2015, the debate of blue-black and white-gold color perception from "the dress" became an overnight internet phenomenon. According to the vote from the online social network Twitter, more people observed white-gold colors than those who observed blue-black colors. Biological explanations have been proposed by neurologist and other scientists, most of which mainly focus on the bias of color perception from visual cortex assuming different illuminants as backgrounds. The goal of this study was to investigate the genetic reason that might be underlying this phenomenon...
2016: PloS One
Luca Santini, Santiago Saura, Carlo Rondinini
One of the biggest challenges in large-scale conservation is quantifying connectivity at broad geographic scales and for a large set of species. Because connectivity analyses can be computationally intensive, and the planning process quite complex when multiple taxa are involved, assessing connectivity at large spatial extents for many species turns to be often intractable. Such limitation results in that conducted assessments are often partial by focusing on a few key species only, or are generic by considering a range of dispersal distances and a fixed set of areas to connect that are not directly linked to the actual spatial distribution or mobility of particular species...
2016: PloS One
Luisanna Cocco, Michele Marchesi
In January 3, 2009, Satoshi Nakamoto gave rise to the "Bitcoin Blockchain", creating the first block of the chain hashing on his computer's central processing unit (CPU). Since then, the hash calculations to mine Bitcoin have been getting more and more complex, and consequently the mining hardware evolved to adapt to this increasing difficulty. Three generations of mining hardware have followed the CPU's generation. They are GPU's, FPGA's and ASIC's generations. This work presents an agent-based artificial market model of the Bitcoin mining process and of the Bitcoin transactions...
2016: PloS One
Peter G Alexander, Karen L Clark, Rocky S Tuan
Limb congenital defects afflict approximately 0.6:1000 live births. In addition to genetic factors, prenatal exposure to drugs and environmental toxicants, represents a major contributing factor to limb defects. Examples of well-recognized limb teratogenic agents include thalidomide, warfarin, valproic acid, misoprostol, and phenytoin. While the mechanism by which these agents cause dymorphogenesis is increasingly clear, prediction of the limb teratogenicity of many thousands of as yet uncharacterized environmental factors (pollutants) remains inexact...
October 21, 2016: Birth Defects Research. Part C, Embryo Today: Reviews
Pamela A Lowry, Morganna L Freeman, Jeffery S Russell
Merkel cell carcinoma (MCC) is a rare and lethal skin cancer with few known treatment options. Management of this disease is challenging, and oncology nurses must understand the medical, physical, and psychosocial burden that MCC places on the patient and family caregivers. Patients must navigate a complex medical and insurance network that often fails to support patients with rare cancers. Nurses must advocate for these patients to ensure quality comprehensive cancer care.
November 1, 2016: Oncology Nursing Forum
Petr Stadlbauer, Liuba Mazzanti, Tristan Cragnolini, David J Wales, Philippe Derreumaux, Samuela Pasquali, Jiri Sponer
G-quadruplexes are the most important non-canonical DNA architectures. Many quadruplex-forming sequences, including the human telomeric sequence d(GGGTTA)n, have been investigated due to their implications in cancer and other diseases, and because of their potential in DNA-based nanotechnology. Despite availability of atomistic structural studies of folded G-quadruplexes, their folding pathways remain mysterious, and mutually contradicting models of folding coexist in the literature. Recent experiments convincingly demonstrated that G-quadruplex folding often takes days to reach the thermodynamics equilibrium...
October 21, 2016: Journal of Chemical Theory and Computation
Lorenza Brocca, Luana Toniolo, Carlo Reggiani, Roberto Bottinelli, Marco Sandri, Maria Antonietta Pellegrino
Muscle atrophy is a complex process that is in common with many different catabolic diseases including disuse/inactivity and ageing. The signalling pathways that control the atrophy program in the different disuse/inactivity conditions have not yet been completely dissected. It has been recently reported that inhibition of FoxO only partially spared muscle mass after denervation. The purposes of this study were: (i) to determine the involvement of FoxOs in hindlimb suspension disuse model, (ii) to define whether the molecular events of protein breakdown are shared among different unloaded muscles and finally (iii) to compare the data obtained in this model with another model of inactivity such as denervation...
October 21, 2016: Journal of Physiology
Erfan Dashtimoghadam, Ghasem Bahlakeh, Hamed Salimi-Kenari, Mohammad Mahdi Hasani-Sadrabadi, Hamid Mirzadeh, Bo Nyström
The temperature-induced gelation of chitosan/glycerophosphate (Chs/GP) systems through physical interactions has shown great potential for various biomedical applications. In the present work, hydroxyethyl cellulose (HEC) was added to the thermosensitive Chs/GP solution to improve the mechanical strength and gel properties of the incipient Chs/HEC/GP gel in comparison with the Chs/GP hydrogel at body temperature. The physical features of the macromolecular complexes formed by the synergistic interaction between chitosan and hydroxyethyl cellulose in the presence of β-glycerophosphate disodium salt solution have been studied essentially from a rheological point of view...
October 21, 2016: Biomacromolecules
Meng-Juan Zhang, Hong-Xi Li, Hai-Yan Li, Jian-Ping Lang
Solvothermal reactions of 5-phenylpyrimidine-2-thiol (5-phpymtH) with equimolar CuBr afforded one hexanuclear cluster [Cu6(μ3-5-phpymt)6] (1) along with a tetranuclear by-product [{(Cu2Br)(μ-5-phpymtH)}(μ3-5-phpymt)]2 (2). A two dimensional (2D) polymer [Cu4(μ5-5-phpymt)2(μ-Br)2]n (3) was isolated from the reaction of 5-phpymtH with two equiv. of CuBr. Analogous reactions of 5-phpymtH with one or four equiv. of CuI produced one tetranuclear cluster [{Cu2(μ-5-phpymtH)(μ-5-phpymt)}(μ3-I)]2 (4) and one 2D polymer [Cu6I2(μ4-I)2(μ4-5-phpymt)2]n (5)...
October 21, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Britta Wandschneider, Matthias J Koepp
Functional MRI studies have helped to elucidate underlying mechanisms in complex neurological and neuropsychiatric disorders. Disease processes often involve complex large-scale network interactions, extending beyond the presumed main disease focus. Given both the complexity of the clinical phenotype and the underlying dysfunctional brain circuits, so called pharmaco-fMRI (ph-MRI) studies probe pharmacological effects on functional neuro-anatomy, and can help to determine early treatment response, mechanisms of drug efficacy and side effects, and potentially advance CNS drug development...
2016: NeuroImage: Clinical
Jillian Iafrati, Arnaud Malvache, Cecilia Gonzalez Campo, M Juliana Orejarena, Olivier Lassalle, Lamine Bouamrane, Pascale Chavis
The postnatal maturation of the prefrontal cortex (PFC) represents a period of increased vulnerability to risk factors and emergence of neuropsychiatric disorders. To disambiguate the pathophysiological mechanisms contributing to these disorders, we revisited the endophenotype approach from a developmental viewpoint. The extracellular matrix protein reelin which contributes to cellular and network plasticity, is a risk factor for several psychiatric diseases. We mapped the aggregate effect of the RELN risk allele on postnatal development of PFC functions by cross-sectional synaptic and behavioral analysis of reelin-haploinsufficient mice...
October 21, 2016: Scientific Reports
Sang-Ho Kwon, Sekyung Oh, Marisa Nacke, Keith E Mostov, Joshua H Lipschutz
Exosomes, 40-150 nm extracellular vesicles, transport biological macromolecules that mediate intercellular communications. While exosomes are known to originate from maturation of endosomes into multivesicular endosomes (MVEs; also known as multivesicular bodies, MVBs) with subsequent fusion of the MVEs with the plasma membrane, it remains unclear how cargos are selected for exosomal release. Using an inducible expression system for the exosome cargo protein GPRC5B and following its trafficking trajectory, we show here that newly synthesized GPRC5B protein accumulates in the Golgi complex prior to its release into exosomes...
October 20, 2016: Journal of Biological Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"