Mechanisms of low-frequency variability in an eddy-resolving midlatitude coupled ocean-atmosphere model

The role of the wind-driven ocean gyres in the midlatitude climate variability is investigated using an idealised, eddy-resolving, quasigeostrophic, coupled model. The model consists of a double gyre box ocean and a periodic channel atmosphere which are coupled together by mixed layers that allow for transfers of heat and momentum. The entire model is driven by fixed, latitudinally-varying solar radiation that is redistributed by a linearised radiation scheme. Our findings reveal a coupled interaction that involves a positive feedback between meridional shifts of the ocean eastward jet extension and downstream displacements of the atmospheric westerly jet. The displacement of the atmospheric jet is resolution-dependent and caused by shifts in the latitudinal centre of low-level baroclinicity, while meridional shifts of the ocean eastward jet are likely controlled by the propagation of baroclinic Rossby waves that form in the eastern basin. Effects of mesoscale turbulence and intrinsic variability of the ocean jet disrupts the arrival of Rossby waves at the western boundary and thus reduces its predictability. In addition, the ocean gyre response is shown to be dependent on forcing location, and a dynamically-distinct, inertial recirculation zone response is found for western basin wind-curl anomalies. Other relevant nonlinear dynamics that maintain the wind-driven ocean gyre circulation are investigated using an adiabatic, fixed-wind, double gyre box ocean model. It is revealed that nonlinear restructuring of the western boundary layer inhibits viscous relative vorticity fluxes, creating an accumulation of enstrophy in the gyres. This enstrophy is advected downstream into the inertial recirculation zones which in turn supports the eastward jet. The growing imbalance in enstrophy is then eventually rectified by inter-gyre potential vorticity fluxes.Open Acces

Successful Bone Union Following Calcium Phosphate Cement-Assisted Percutaneous Transpedicular Balloon Kyphoplasty of a Large Interbody Cleft on Long-term Hemodialysis Patient

A 68-year-old diabetic man, who had been on dialysis for 3 years, suffered a five week history of severe back pain that was unresponsive to bed rest, analgesics, and bracing. The vertebral cleft formed by an injury gradually increased in size on sequential plain films. Hence, he underwent calcium phosphate cement-assisted percutaneous transpedicular balloon kyphoplasty to treat a painful interbody vacuum cleft. Immediate pain relief and firm bone union were obtained

Electrochemical Oxidation of Glucose Using Copper Hydroxide Nanosheets

In this study, we synthesized copper hydroxide nanosheet and investigated electrochemical oxidation of glucose using the copper hydroxide nanosheets. The precursor of the nanosheet was a layered copper hydroxide synthesized by the ion exchange of dodecylbenzene sulfonate with acetate in Cu2(OH)3(CH3COO)·H2O. Delamination of the layered copper hydroxide prepared the nanosheet by dispersion in 1-butanol. Atomic force microscopy images of the nanosheets showed lateral dimensions of ca. 2 μm with a height of ca. 4.5 nm. Cyclic voltammogram of the nanosheet coated electrode showed oxidation current peak depend on the concentration of glucose at around +0.6 V vs. Ag/AgCl. Amperometry was measured at +0.6V vs. Ag/AgCl with successive addition of glucose solution. Glucose concentration and catalytic current were almost proportional. When the linear range is 0.1 to 4.9 mM, the sensitivity was 1.16 mA mM-1cm-2 from the slope

Enzyme-free release of adhered cells from standard culture dishes using intermittent ultrasonic traveling waves.

Cell detachment is essential in culturing adherent cells. Trypsinization is the most popular detachment technique, even though it reduces viability due to the damage to the membrane and extracellular matrix. Avoiding such damage would improve cell culture efficiency. Here we propose an enzyme-free cell detachment method that employs the acoustic pressure, sloshing in serum-free medium from intermittent traveling wave. This method detaches 96.2% of the cells, and increases its transfer yield to 130% of conventional methods for 48 h, compared to the number of cells detached by trypsinization. We show the elimination of trypsinization reduces cell damage, improving the survival of the detached cells. Acoustic pressure applied to the cells and media sloshing from the intermittent traveling wave were identified as the most important factors leading to cell detachment. This proposed method will improve biopharmaceutical production by expediting the amplification of tissue-cultured cells through a more efficient transfer process

Inducing Mild Traumatic Brain Injury in C. elegans via Cavitation-Free Surface Acoustic Wave-Driven Ultrasonic Irradiation.

Mild traumatic brain injury is an all-too-common outcome from modern warfare and sport, and lacks a reproducible model for assessment of potential treatments and protection against it. Here we consider the use of surface acoustic wave (SAW) irradiation of C. elegans worms-without cavitation-as a potential, ethically reasonable animal-on-a-chip model for inducing traumatic brain injury in an animal, producing significant effects on memory and learning that could prove useful in a model that progress from youth to old age in but a few weeks. We show a significant effect by SAW on the ability of worms to learn post-exposure through associative learning chemotaxis. At higher SAW intensity, we find immediate, thorough, but temporary paralysis of the worms. We further explore the importance of homogeneous exposure of the worms to the SAW-driven ultrasound, an aspect poorly controlled in past efforts, if at all, and demonstrate the absence of cavitation through a change in fluids from a standard media for the worms to the exceedingly viscous polyvinyl alcohol. Likewise, we demonstrate that acoustic streaming, when present, is not directly responsible for paralysis nor learning disabilities induced in the worm, but is beneficial at low amplitudes to ensuring homogeneous ultrasound exposure

Osteoinduction with HA/TCP Ceramics of Different Composition and Porous Structure in Rabbits

AbstractTo determine the effect of material factors on Ca-P biomaterial-induced osteogenesis, six kinds of biphasic calcium phosphate (BCP) ceramics with different HA to TCP ratio (HA/TCP 2-8, 7-3) and different porous structure (micro-, macro- and micro/macro- porous structures) were implanted intramuscularly in rabbits. Different tissue response was detected histologically and microradiographically after the ceramic samples were implanted in the dorsal muscles of rabbits for 3 and 6 months. Obvious bone formation was found in two kinds of ceramics with the same micro/macro- porous structure at both 3 and 6 months. In contrast, no bone formation or host tissue invasion was detected in two other kinds of ceramics with only microporous structure, even after 6 months implantation. Some bone formation was found occasionally in two kinds of ceramics with only macro-porous structure at 6 months. Bone tissue was usually formed in direct contact with the pore surface and was only located in non-dissolved porous regions. Osteocyte lacunae were seen and no pathological calcifications were observed. These results indicate that micro- and macro-porous structure play an important role in the osteoinduction with Ca-P ceramics. Furthermore, the results showed that the osteoinductive capacity of BCP ceramics was influenced by the different dissolution rate through changing HA/TCP ratio