Read by QxMD icon Read


Julia Stilkerich, Trisha A Smrecak, Kenneth De Baets
We herein examine the only known non-planispirally coiled early Devonian ammonoid, the holotype specimen of Ivoites opitzi, to investigate if the host was encrusted in vivo and if these sclerobionts were responsible for the trochospiral coiling observed in this unique specimen. To test if the presence of runner-like sclerobionts infested the historically collected specimen of Ivoites opitzi during its life, we used microCT to produce a three-dimensional model of the surface of the specimen. Our results indicate that sclerobionts grew across the outer rim (venter) on both sides of the ammonoid conch at exactly the location where the deviation from the planispiral was recognized, and where subsequent ammonoid growth would likely preclude encrustation...
2017: PeerJ
Grace X Gu, Mahdi Takaffoli, Markus J Buehler
An order of magnitude tougher than nacre, conch shells are known for being one of the toughest body armors in nature. However, the complexity of the conch shell architecture creates a barrier to emulating its cross-lamellar structure in synthetic materials. Here, a 3D biomimetic conch shell prototype is presented, which can replicate the crack arresting mechanisms embedded in the natural architecture. Through an integrated approach combining simulation, additive manufacturing, and drop tower testing, the function of hierarchy in conch shell's multiscale microarchitectures is explicated...
May 26, 2017: Advanced Materials
Sushmita Chakraborty, Bianca Kloos, Ulrike Harre, Georg Schett, Katharina F Kubatzky
Bone remodeling is a continuous process to retain the structural integrity and function of the skeleton. A tight coupling is maintained between osteoclast-mediated resorption of old or damaged bones and osteoblast-mediated formation of new bones for bone homeostasis. While osteoblasts differentiate from mesenchymal stem cells, osteoclasts are hematopoietic in origin and derived from myeloid precursor cells. Osteoclast differentiation is driven by two cytokines, cytokine receptor activator of NF-κB ligand (RANKL), and macrophage colony-stimulating factor...
2017: Frontiers in Immunology
Larisa A Doguzhaeva, Stefan Bengtson, Marcelo A Reguero, Thomas Mörs
BACKGROUND: The Subclass Coleoidea (Class Cephalopoda) accommodates the diverse present-day internally shelled cephalopod mollusks (Spirula, Sepia and octopuses, squids, Vampyroteuthis) and also extinct internally shelled cephalopods. Recent Spirula represents a unique coleoid retaining shell structures, a narrow marginal siphuncle and globular protoconch that signify the ancestry of the subclass Coleoidea from the Paleozoic subclass Bactritoidea. This hypothesis has been recently supported by newly recorded diverse bactritoid-like coleoids from the Carboniferous of the USA, but prior to this study no fossil cephalopod indicative of an endochochleate branch with an origin independent from subclass Bactritoidea has been reported...
2017: PloS One
Sue-Ann Watson, Jennifer B Fields, Philip L Munday
Ocean acidification poses a range of threats to marine invertebrates; however, the emerging and likely widespread effects of rising carbon dioxide (CO2) levels on marine invertebrate behaviour are still little understood. Here, we show that ocean acidification alters and impairs key ecological behaviours of the predatory cone snail Conus marmoreus Projected near-future seawater CO2 levels (975 µatm) increased activity in this coral reef molluscivore more than threefold (from less than 4 to more than 12 mm min(-1)) and decreased the time spent buried to less than one-third when compared with the present-day control conditions (390 µatm)...
February 2017: Biology Letters
Qing Yang, Zewei Wang, Lixia Yang, Yonghua Xu, Li Min Chen
This study aims to characterize the psychological wellbeing of chronic headache (CH) patients, to identify cortical structural abnormalities and any associations of those abnormalities with resting state functional connectivity (rsFC), and to determine whether such rsFC abnormality is specific to CH patients. Compared with healthy controls (CONCH ), CH patients suffered from mild depression, sleep disturbances, and relatively poor quality of life. CH patients also exhibited widespread cortical thickness (CT) abnormalities in left premotor (BA6), right primary somatosensory (S1) and right prefrontal (BA10) cortices, as well as in regions of default mode and executive control networks...
January 4, 2017: Human Brain Mapping
Zewei Wang, Qing Yang, Li Min Chen
The goals of this study are to characterize the temporal dynamics of inter-regional connectivity of the brain in chronic headache (CH) patients versus their age/gender matched controls (CONCH, n=28 pairs), and to determine whether dynamic measures reveal additional features to static functional connectivity and correlate with psychometric scores. Cortical thickness and inter-regional resting state fMRI connectivity were quantified and compared between CH and CONCH groups. Six cortical regions of interest (ROI) pairs that exhibited correlated cortical thickness and static functional connectivity abnormalities were selected for temporal dynamic analysis...
February 2017: Magnetic Resonance Imaging
Rui-Wen Zong, Ruo-Ying Fan, Yi-Ming Gong
A nautiloid conch containing many disarticulated exoskeletons of Omegops cornelius (Phacopidae, Trilobita) was found in the Upper Devonian Hongguleleng Formation of the northwestern margin of the Junggar Basin, NW China. The similar number of cephala, thoraces and pygidia, unbroken thoraces, explicit exuviae, and lack of other macrofossils in the conch, indicate that at least seven individual trilobites had moulted within the nautiloid living chamber, using the vacant chamber of a dead nautiloid as a communal place for ecdysis...
October 5, 2016: Scientific Reports
Ian M R Wright, Joanna L Latter, Rebecca M Dyson, Chris R Levi, Vicki L Clifton
The perinatal period remains a time of significant risk of death or disability. Increasing evidence suggests that this depends on microcirculatory behavior. Sidestream dark-field orthogonal polarized light videomicroscopy (OPS) has emerged as a useful assessment of adult microcirculation but the values derived are not delineated for the newborn. We aimed to define these parameters in well term newborn infants. Demographic details were collected prospectively on 42 healthy term neonates (n = 20 females, n = 22 males)...
October 2016: Physiological Reports
H Iwasaki
The nutrition of the free-living phase of Conchocelis of P. tenera was studied axenically. Conch-ocelis preferred NO3 , as nitrogen source. Urea and NH4 in low concentration, asparagine, and lysine were very good N sources. Several other amino acids were also utilized but growth was less abundant. Inorganic and organic phosphates were utilized; they were required at relatively low concentrations. Glycerophosphate gave excellent growth in a comparatively wide range of concentrations (0.1-5 mg P %). The optimal Ca concentration was 10-100 mg %...
March 1967: Journal of Phycology
Diogo R Couto, Philippe Bouchet, Yuri I Kantor, Luiz R L Simone, Gonzalo Giribet
The neogastropod family Fasciolariidae Gray, 1853 - tulips, horse-conchs, spindles, etc., comprises important representatives of tropical and subtropical molluscan assemblages, with over 500 species in the subfamilies Fasciolariinae Gray, 1853, Fusininae Wrigley, 1927 and Peristerniinae Tryon, 1880. Fasciolariids have had a rather complicated taxonomical history, with several genus names for a long time used as waste baskets to group many unrelated species; based on shell characters, recent taxonomic revisions have, however, began to set some order in its taxonomy...
June 2016: Molecular Phylogenetics and Evolution
S Bauer, H Baier, C Baumgartner, K Bohlmann, S Fauser, W Graf, B Hillenbrand, M Hirsch, C Last, H Lerche, T Mayer, A Schulze-Bonhage, B J Steinhoff, Y Weber, A Hartlep, F Rosenow, H M Hamer
BACKGROUND: Various brain stimulation techniques are in use to treat epilepsy. These methods usually require surgical implantation procedures. Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive technique to stimulate the left auricular branch of the vagus nerve at the ear conch. OBJECTIVE: We performed a randomized, double-blind controlled trial (cMPsE02) to assess efficacy and safety of tVNS vs. control stimulation in patients with drug-resistant epilepsy...
May 2016: Brain Stimulation
Veronique Cerezo, Florence Conche
This paper presents the results of a study dealing with the risk for heavy vehicles in ramps. Two approaches are used. On one hand, statistics are applied on several accidents databases to detect if ramps are more risky for heavy vehicles and to define a critical value for longitudinal slope. χ(2) test confirmed the risk in ramps and statistical analysis proved that a longitudinal slope superior to 3.2% represents a higher risk for heavy vehicles. On another hand, numerical simulations allow defining the speed profile in ramps for two types of heavy vehicles (tractor semi-trailer and 2-axles rigid body) and different loads...
June 2016: Accident; Analysis and Prevention
Dawrin Pech-Puch, Honorio Cruz-López, Cindy Canche-Ek, Gabriela Campos-Espinosa, Elpidio García, Maite Mascaro, Carlos Rosas, Daniel Chávez-Velasco, Sergio Rodríguez-Morales
Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod...
2016: PloS One
Yoon Ah Shin, Sheng Yin, Xiaoyan Li, Subin Lee, Sungmin Moon, Jiwon Jeong, Minhyug Kwon, Seung Jo Yoo, Young-Min Kim, Teng Zhang, Huajian Gao, Sang Ho Oh
As a natural biocomposite, Strombus gigas, commonly known as the giant pink queen conch shell, exhibits outstanding mechanical properties, especially a high fracture toughness. It is known that the basic building block of conch shell contains a high density of growth twins with average thickness of several nanometres, but their effects on the mechanical properties of the shell remain mysterious. Here we reveal a toughening mechanism governed by nanoscale twins in the conch shell. A combination of in situ fracture experiments inside a transmission electron microscope, large-scale atomistic simulations and finite element modelling show that the twin boundaries can effectively block crack propagation by inducing phase transformation and delocalization of deformation around the crack tip...
2016: Nature Communications
Luise Westernberg, Claire Conche, Yina Hsing Huang, Stephanie Rigaud, Yisong Deng, Sabine Siegemund, Sayak Mukherjee, Lyn'Al Nosaka, Jayajit Das, Karsten Sauer
β-selection is the most pivotal event determining αβ T cell fate. Here, surface-expression of a pre-T cell receptor (pre-TCR) induces thymocyte metabolic activation, proliferation, survival and differentiation. Besides the pre-TCR, β-selection also requires co-stimulatory signals from Notch receptors - key cell fate determinants in eukaryotes. Here, we show that this Notch-dependence is established through antagonistic signaling by the pre-TCR/Notch effector, phosphoinositide 3-kinase (PI3K), and by inositol-trisphosphate 3-kinase B (Itpkb)...
February 11, 2016: ELife
Mine Gültekin-Özgüven, Ayşe Karadağ, Şeyma Duman, Burak Özkal, Beraat Özçelik
Fine-disperse anionic liposomes containing black mulberry (Morus nigra) extract (BME) were prepared by high pressure homogenization at 25,000 psi. Primary liposomes were coated with cationic chitosan (0.4, w/v%) using the layer-by-layer depositing method and mixed with maltodextrin (MD) (20, w/v%) prior to spray drying. After that, spray dried liposomal powders containing BME were added to chocolates with alkalization degrees (pH 4.5, 6, 7.5) at conching temperatures of 40 °C, 60 °C, and 80 °C. The results showed that, compared to spray dried extract, chitosan coated liposomal powders provided better protection of anthocyanin content in both increased temperature and pH...
June 15, 2016: Food Chemistry
F Albak, A R Tekin
Variation in the volatiles, total polyphenol, theobromine and caffein was investigated both qualitatively and quantitatively for all phases of conching with GC/MS/SPME, HPLC, GC/O, and UV-visible spectrophotometry. The volatile compounds being identified during the three phases consisted of aldehydes, ketones, pyrazines, acids, alcohols and esters. The number and concentration of these compounds were observed to be 31-25,681 ppb, 44-34,838 ppb and 44-29,809 ppb in the dry, pasty, and liquid phases respectively...
January 2016: Journal of Food Science and Technology
Lochan Singh, Jay G Varshney, Tripti Agarwal
Polycyclic aromatic hydrocarbons (PAHs) emerged as an important contaminant group in a gamut of processed food groups like dairy, nuts, herbs, beverages, meat products etc. Different cooking processes and processing techniques like roasting, barbecuing, grilling, smoking, heating, drying, baking, ohmic-infrared cooking etc. contribute towards its formation. The level of PAHs depends on factors like distance from heat source, fuel used, level of processing, cooking durations and methods, whereas processes like reuse, conching, concentration, crushing and storage enhance the amount of PAHs in some food items...
May 15, 2016: Food Chemistry
Pierre Hennebert, Nicolas Humez, Isabelle Conche, Ian Bishop, Flore Rebischung
Legislation published in December 2014 revised both the List of Waste (LoW) and amended Appendix III of the revised Waste Framework Directive 2008/98/EC; the latter redefined hazardous properties HP 1 to HP 13 and HP 15 but left the assessment of HP 14 unchanged to allow time for the Directorate General of the Environment of the European Commission to complete a study that is examining the impacts of four different calculation methods for the assessment of HP 14. This paper is a contribution to the assessment of the four calculation methods...
February 2016: Waste Management
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"