keyword
MENU ▼
Read by QxMD icon Read
search

Mechanical engineering

keyword
https://www.readbyqxmd.com/read/28735148/mechanically-competent-and-cytocompatible-polycaprolactone-borophosphosilicate-hybrid-biomaterials
#1
Dibakar Mondal, S Jeffrey Dixon, Kibret Mequanint, Amin S Rizkalla
Organic-inorganic class II hybrid materials have domain sizes at the molecular level and chemical bonding between the organic and inorganic phases. We have previously reported the synthesis of class II hybrid biomaterials from alkoxysilane-functionalized polycaprolactone (PCL) and borophosphosilicate (B2O3-P2O5-SiO2) glass (BPSG) through a non-aqueous sol-gel process. In the present study, the mechanical properties and degradability of these PCL/BPSG hybrid biomaterials were studied and compared to those of their conventional composite counterparts...
July 5, 2017: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/28734899/strategies-to-develop-endogenous-stem-cell-recruiting-bioactive-materials-for-tissue-repair-and-regeneration
#2
Settimio Pacelli, Sayantani Basu, Jonathan Whitlow, Aparna R Chakravarti, Francisca Acosta, Arushi Varshney, Saman Modaresi, Cory Berkland, Arghya Paul
A leading strategy in tissue engineering is the design of biomimetic scaffolds that stimulate the body's repair mechanisms through the recruitment of endogenous stem cells to sites of injury. Approaches that employ the use of chemoattractant gradients to guide tissue regeneration without external cell sources are favored over traditional cell-based therapies that have limited potential for clinical translation. Following this concept, bioactive scaffolds can be engineered to provide a temporally and spatially controlled release of biological cues, with the possibility to mimic the complex signaling patterns of endogenous tissue regeneration...
July 19, 2017: Advanced Drug Delivery Reviews
https://www.readbyqxmd.com/read/28734802/co-transplantation-of-mesenchymal-and-neural-stem-cells-and-overexpressing-stromal-derived-factor-1-for-treating-spinal-cord-injury
#3
Andrew N Stewart, Griffin Kendziorski, Zachary M Deak, Dara J Brown, Matthew N Fini, Katherine L Copely, Julien Rossignol, Gary L Dunbar
Genetic engineering of mesenchymal stem cells (MSCs) and neuronal stem cells (NSCs) has been used to treat spinal cord injuries (SCI). As a mechanism of therapy, MSCs secrete high amounts of anti-inflammatory cytokines and trophic factors, while NSCs can differentiate into neuronal lineages and aid in tissue replacement. Additionally, the forced overexpression of secreted proteins can enhance the secretome of transplanted cells, which can increase therapeutic efficacy. This study utilized a combinational treatment consisting of MSCs, NSCs, and the forced overexpression of the chemokine stromal-derived factor-1 (SDF-1) from MSCs (SDF-1-MSCs), to treat a rat model of SCI...
July 19, 2017: Brain Research
https://www.readbyqxmd.com/read/28734258/mechanical-properties-and-biocompatibility-of-porous-titanium-scaffolds-for-bone-tissue-engineering
#4
Yunhui Chen, Jessica Ellen Frith, Ali Dehghan-Manshadi, Hooyar Attar, Damon Kent, Nicolas Dominique Mathieu Soro, Michael J Bermingham, Matthew S Dargusch
Synthetic scaffolds are a highly promising new approach to replace both autografts and allografts to repair and remodel damaged bone tissue. Biocompatible porous titanium scaffold was manufactured through a powder metallurgy approach. Magnesium powder was used as space holder material which was compacted with titanium powder and removed during sintering. Evaluation of the porosity and mechanical properties showed a high level of compatibility with human cortical bone. Interconnectivity between pores is higher than 95% for porosity as low as 30%...
July 13, 2017: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/28733634/unconventional-band-inversion-and-intrinsic-quantum-spin-hall-effect-in-functionalized-group-v-binary-films
#5
Sheng-Shi Li, Wei-Xiao Ji, Ping Li, Shu-Jun Hu, Tie Zhou, Chang-Wen Zhang, Shi-Shen Yan
Adequately understanding band inversion mechanism, one of the significant representations of topological phase, has substantial implications for design and regulation of topological insulators (TIs). Here, by identifying an unconventional band inversion, we propose an intrinsic quantum spin Hall (QSH) effect in iodinated group-V binary (ABI2) monolayers with a bulk gap as large as 0.409 eV, guaranteeing its viable application at room temperature. The nontrivial topological characters, which can be established by explicit demonstration of Z2 invariant and gapless helical edge states, are derived from the band inversion of antibonding states of p x,y orbitals at the K point...
July 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28733420/sg2-type-r2r3-myb-transcription-factor-myb15-controls-defense-induced-lignification-and-basal-immunity-in-arabidopsis
#6
William R Chezem, Altamash Memon, Fu-Shuang Li, Jing-Ke Weng, Nicole Kho Clay
Lignification of cell wall appositions is a conserved basal defense mechanism in the plant innate immune response. However, the genetic pathway controlling defense-induced lignification remains unknown. Here, we demonstrate the Arabidopsis thaliana SG2-type R2R3-MYB transcription factor MYB15 as a regulator of defense-induced lignification and basal immunity. Loss of MYB15 reduces the content but not the composition of defense-induced lignin, whereas constitutive expression of MYB15 increases lignin content independently of immune activation...
July 21, 2017: Plant Cell
https://www.readbyqxmd.com/read/28733281/structural-and-mechanistic-insights-into-the-improvement-of-halotolerant-ability-of-a-marine-microbial-esterase-by-increasing-intra-and-inter-domain-hydrophobic-interactions
#7
Ping-Yi Li, Yi Zhang, Bin-Bin Xie, Yan-Qi Zhang, Jie Hao, Yue Wang, Peng Wang, Chun-Yang Li, Qi-Long Qin, Xi-Ying Zhang, Hai-Nan Su, Mei Shi, Yu-Zhong Zhang, Xiu-Lan Chen
Halotolerant enzymes are beneficial for industrial processes requiring high salts and low water activity. Most halophilic proteins are evolved to have reduced hydrophobic interactions on the surface and in the hydrophobic cores for their haloadaptation. However, in this study, we improved the halotolerance of a thermolablie esterase, E40, by increasing intra-protein hydrophobic interactions. E40 was quite unstable in buffers containing more than 0.3 M NaCl and its kcat and substrate affinity were both significantly reduced in 0...
July 21, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28733255/nanofiber-structured-hydrogel-yarns-with-ph-response-capacity-and-cardiomyocyte-drivability-for-bio-microactuator-application
#8
Shaohua Wu, Bin Duan, Xiaohong Qin, Jonathan T Butcher
Polymeric hydrogels have great potential in soft biological micro-actuator applications. However, inappropriate micro-architecture, non-anisotropy, weak biomechanics, and inferior response behaviors limit their development. In this study, we designed and manufactured novel polyacrylonitrile (PAN)-based hydrogel yarns composed with uniaxially aligned nanofibers. The nanofibrous hydrogel yarns possessed anisotropic architecture and robust mechanical properties with flexibility, and could be assembled into defined scaffold structures by subsequent processes...
July 18, 2017: Acta Biomaterialia
https://www.readbyqxmd.com/read/28732264/insights-into-plant-phosphate-sensing-and-signaling
#9
REVIEW
Byung-Kook Ham, Jieyu Chen, Yan Yan, William J Lucas
Phosphorus (P) is a macronutrient essential for plant growth, therefore, soil P level is critical to crop yield potential in agriculture. As Pi levels limit crop yield under many soil conditions, it is crucial to understand the mechanisms by which plants adapt to low-phosphate (Pi) soil conditions and interact with their soil microbiome to improve crop P use efficiency, in order to ensure global food security. Recent advances have been made towards achieving this goal through advancing our understanding of the plant's response to limiting Pi conditions to maintain P homeostasis...
July 18, 2017: Current Opinion in Biotechnology
https://www.readbyqxmd.com/read/28731752/novel-pd_-2-se_-3-two-dimensional-phase-driven-by-interlayer-fusion-in-layered-pdse_-2
#10
Junhao Lin, Sebastian Zuluaga, Peng Yu, Zheng Liu, Sokrates T Pantelides, Kazu Suenaga
Two-dimensional (2D) materials are easily fabricated when their bulk form has a layered structure. The monolayer form in layered transition-metal dichalcogenides is typically the same as a single layer of the bulk material. However, PdSe_{2} presents a puzzle. Its monolayer form has been theoretically shown to be stable, but there have been no reports that monolayer PdSe_{2} has been fabricated. Here, combining atomic-scale imaging in a scanning transmission electron microscope and density functional theory, we demonstrate that the preferred monolayer form of this material amounts to a melding of two bulk monolayers accompanied by the emission of Se atoms so that the resulting stoichiometry is Pd_{2}Se_{3}...
July 7, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28731528/improving-succinate-productivity-by-engineering-a-cyanobacterial-co2-concentrating-system-ccm-in-escherichia-coli
#11
Mengyong Xiao, Xinna Zhu, Changhao Bi, Yanhe Ma, Xueli Zhang
Biologically fixation of CO2 has great potential as a significant carbon source for biosynthesis, which is also a major way to reduce CO2 accumulation in atmosphere. Phosphoenolpyruvate (PEP) carboxylation is the key step of anaerobic succinate production in Escherichia coli. In this reaction, one mole CO2 is assimilated with PEP to form oxaloacetate by PEP carboxykinase (PCK). The preferred substrate of PCK is CO2 , which is very limited in cytoplasm. In this study, the carbon concentration mechanism (CCM) of cyanobacteria was introduced into E...
July 21, 2017: Biotechnology Journal
https://www.readbyqxmd.com/read/28731527/mechanotransduction-effects-on-endothelial-cell-proliferation-via-cd31-and-vegfr2-implications-for-immunomagnetic-separation
#12
Kalpesh D Mahajan, Gauri M Nabar, Wei Xue, Mirela Anghelina, Nicanor Moldovan, Jeffrey Chalmers, Jessica Winter
Immunomagnetic separation is used to isolate circulating endothelial cells (ECs) and endothelial progenitor cells (EPCs) for diagnostics and tissue engineering. However, potentially detrimental changes in cell properties have been observed post-separation. Here, we studied the effect of mechanical force, which is naturally applied during immunomagnetic separation, on proliferation of human umbilical vein endothelial cells (HUVEC), kinase insert domain-positive receptor (KDR) cells, and peripheral blood mononuclear cells (PBMCs)...
July 21, 2017: Biotechnology Journal
https://www.readbyqxmd.com/read/28731326/oxygen-partial-pressure-during-pulsed-laser-deposition-deterministic-role-on-thermodynamic-stability-of-atomic-termination-sequence-at-srruo3-batio3-interface
#13
Yeong Jae Shin, Lingfei Wang, Yoonkoo Kim, Ho-Hyun Nahm, Daesu Lee, Jeong Rae Kim, Sang Mo Yang, Jong-Gul Yoon, Jin-Seok Chung, Miyoung Kim, Seo Hyoung Chang, Tae Won Noh
With recent trends on miniaturizing oxide-based devices, the need for atomic-scale control of surface/interface structures by pulsed laser deposition (PLD) has increased. In particular, realizing uniform atomic termination at the surface/interface is highly desirable. However, a lack of understanding on the surface formation mechanism in PLD has limited a deliberate control of surface/interface atomic stacking sequences. Here, taking the prototypical SrRuO3/BaTiO3/SrRuO3 (SRO/BTO/SRO) heterostructure as a model system, we investigated the formation of different interfacial termination sequences (BaO-RuO2 or TiO2-SrO) with oxygen partial pressure (PO2) during PLD...
July 21, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28729866/cytokine-induced-killer-cells-as-pharmacological-tools-for-cancer-immunotherapy
#14
REVIEW
Xingchun Gao, Yajing Mi, Na Guo, Hao Xu, Lixian Xu, Xingchun Gou, Weilin Jin
Cytokine-induced killer (CIK) cells are a heterogeneous population of effector CD3(+)CD56(+) natural killer T cells, which can be easily expanded in vitro from peripheral blood mononuclear cells. CIK cells work as pharmacological tools for cancer immunotherapy as they exhibit MHC-unrestricted, safe, and effective antitumor activity. Much effort has been made to improve CIK cells cytotoxicity and treatments of CIK cells combined with other antitumor therapies are applied. This review summarizes some strategies, including the combination of CIK with additional cytokines, dendritic cells, check point inhibitors, antibodies, chemotherapeutic agents, nanomedicines, and engineering CIK cells with a chimeric antigen receptor...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28729840/cardiac-subtype-specific-modeling-of-kv1-5-ion-channel-deficiency-using-human-pluripotent-stem-cells
#15
Maike Marczenke, Ilaria Piccini, Isabella Mengarelli, Jakob Fell, Albrecht Röpke, Guiscard Seebohm, Arie O Verkerk, Boris Greber
The ultrarapid delayed rectifier K(+) current (IKur), mediated by Kv1.5 channels, constitutes a key component of the atrial action potential. Functional mutations in the underlying KCNA5 gene have been shown to cause hereditary forms of atrial fibrillation (AF). Here, we combine targeted genetic engineering with cardiac subtype-specific differentiation of human induced pluripotent stem cells (hiPSCs) to explore the role of Kv1.5 in atrial hiPSC-cardiomyocytes. CRISPR/Cas9-mediated mutagenesis of integration-free hiPSCs was employed to generate a functional KCNA5 knockout...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28729713/tunable-uptake-release-mechanism-of-protein-microgel-particles-in-biomimicking-environment
#16
A Pepe, P Podesva, G Simone
Microgels are intra-molecular crosslinked macromolecules that can be used as vehicles to deliver and release drugs at the point-of-need in the patient's body. Here, gelatin microgels were formed from microfluidics droplets, stabilised by aldehydes and frozen into a spheroidal shape. Microgel morphology and response to external stimuli were characterised. It was found that the behaviour of the spheroidal microgels was sensitive to both pH and ionic strength and that the distribution of charges into the microgels affected the behaviour of swelling and uptake...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28728412/role-of-interfaces-in-the-elasticity-and-failure-of-clay-organic-nanocomposites-toughening-upon-interface-weakening
#17
Gyorgy Hantal, Laurent Brochard, Roland J-M Pellenq, Franz-Josef Ulm, Benoit Coasne
Synthetic organic-inorganic composites constitute a new class of engineering materials finding applications in an increasing range of fields. The interface between the constituting phases plays a pivotal role in the enhancement of mechanical properties. In exfoliated clay-organic nanocomposites, individual, high aspect ratio clay sheets are dispersed in the organic matrix providing large interfaces and hence efficient stress transfer. In this study, we aim at elucidating molecular-scale reinforcing mechanisms in a series of model clay-organic composite systems by means of reactive molecular simulations...
July 20, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28728125/assessment-and-prediction-of-joint-algal-toxicity-of-binary-mixtures-of-graphene-and-ionic-liquids
#18
Zhuang Wang, Fan Zhang, Se Wang, Willie J G M Peijnenburg
Graphene and ionic liquids (ILs) released into the environment will interact with each other. So far however, the risks associated with the concurrent exposure of biota to graphene and ILs in the environment have received little attention. The research reported here focused on observing and predicting the joint toxicity effects in the green alga Scenedesmus obliquus exposed to binary mixtures of intrinsic graphene (iG)/graphene oxide (GO) and five ILs of varying anionic and cationic types. The isolated ILs in the binary mixtures were the main contributors to toxicity...
July 8, 2017: Chemosphere
https://www.readbyqxmd.com/read/28727446/reductive-outer-sphere-single-electron-transfer-is-an-exception-rather-than-the-rule-in-natural-and-engineered-chlorinated-ethene-dehalogenation
#19
Benjamin Heckel, Stefan Cretnik, Sarah Kliegman, Orfan Shouakar-Stash, Kristopher McNeill, Martin Elsner
Chlorinated ethenes (CEs) such as perchloroethylene, trichloroethylene and dichloroethylene are notorious groundwater contaminants. Although reductive dehalogenation is key to their environmental and engineered degradation, underlying reaction mechanisms remain elusive. Outer-sphere reductive single electron transfer (OS-SET) has been proposed for such different processes as Vitamin B12-dependent biodegradation and zero-valent metal-mediated dehalogenation. Compound-specific isotope effect (13C/12C, 37Cl/35Cl) analysis offers a new opportunity to test these hypotheses...
July 20, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28726917/engineering-micromyocardium-to-delineate-cellular-and-extracellular-regulation-of-myocardial-tissue-contractility
#20
Nethika R Ariyasinghe, Caitlin H Reck, Alyssa A Viscio, Andrew P Petersen, Davi M Lyra-Leite, Nathan Cho, Megan L McCain
Cardiovascular diseases are a leading cause of death, in part due to limitations of existing models of the myocardium. Myocardium consists of aligned, contractile cardiac myocytes interspersed with fibroblasts that synthesize extracellular matrix (ECM). The cellular demographics and biochemical and mechanical properties of the ECM remodel in many different cardiac diseases. However, the impact of diverse cellular and extracellular remodeling on the contractile output of the myocardium are poorly understood...
July 20, 2017: Integrative Biology: Quantitative Biosciences From Nano to Macro
keyword
keyword
2577
1
2
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"