Crustal deformation at the Sumatran Subduction Zone revealed by coral rings

Analyses of coral rings grown in the interval 1970–1997 reveal a geographically distinct pattern of interseismic uplift off Sumatra's western coast. At distances less than 110 km from the Sumatran trench, coral reefs are submerging as fast as 5 mm/y. At 130 and 180 km distance from the trench, they are emerging at similar rates. We suggest that a locked, or partially locked patch, located above 30 km depth on the upper surface of the subducting oceanic plate, generates this pattern

The development of novel hydrogel composites for use in bone tissue engineering

Objectives Hydrogels are gaining interest as biomaterials in bone tissue engineering (BTE). However, hydrogels must be mechanically stable, receptive to mineralisation, non-cytotoxic and support adhesion and growth of bone forming cells. Ease of sterilisation and antibacterial activity are also desirable.  This study evaluated the extent to which three hydrogels fulfilled these criteria: 1.Electron irradiated Gelatin hydrogels supplemented with Alkaline Phosphatase (ALP) 2.Whey Protein Isolate (WPI) hydrogels supplemented with Phloroglucinol (PG) 3.WPI hydrogels supplemented with Carbon Nanotubes (CNTs) Methods Gelatin hydrogels were crosslinked using electron beam irradiation and subject to ALP-mediated mineralisation. Mineralisation was evaluated by spectroscopic and microscopical techniques. Mechanical properties were examined via compressive testing. Cytocompatibility was assessed using osteoblast-like MG-63 cells. Similarly, 40% WPI solution was supplemented with CNTs or PG prior to simultaneous hydrogel fabrication and sterilisation by autoclaving. Antibacterial properties of WPI-CNT hydrogels were assessed using Staphylococcus aureus. Cell viability was assessed against Human Foetal Osteoblast (hFOB; WPI-CNT only) and MG-63 cells. Surface topography and molecular structures were evaluated microscopically and spectroscopically. The effect of CNT/PG supplementation on mechanical properties was also evaluated. Results Calcium phosphate (CaP) deposits were successfully formed in gelatin-ALP hydrogels, which coincided with an elevated compressive modulus. Importantly, electron beam-crosslinked hydrogels, both mineralized and unmineralized, supported MG-63 cell adhesion and proliferation. Both CNTs and PG were successfully incorporated into WPI hydrogels. CNTs interacted with WPI and increased stiffness, but not compressive strength, of hydrogel composites. PG concentration had little impact on hydrogel mechanical properties. Importantly, WPI-CNT hydrogels exhibited antibacterial activity and supported growth of MG-63 cells. However, MG-63 viability appeared to reduce with increasing PG concentration. Conclusions The successful supplementation of hydrogels with additives to confer desirable properties, coupled with the practicality of simultaneous fabrication and sterilisation, demonstrates their applicability in BTE and future research in this space

Control of Type III-mediated Virulence in Pseudomonas syringae by Cyclic-di-GMP

Pseudomonas syringae is a prominent plant pathogen and disease model organism. These bacteria carry out host infection using the type III secretion system (T3SS), which translocates effector proteins into target cells, altering cellular defence mechanisms and metabolism to promote bacterial colonisation. It was previously shown that the secondary signalling molecule cyclic-di-GMP (CdG) binds to the export ATPase complex at the base of the T3SS (HrcN in P. syringae), as well as in closely related homologue proteins. It was hypothesised that this binding interaction plays a role in controlling type III-mediated virulence. To investigate the CdG:HrcN binding interaction, bacterial strains carrying mutations targeting key predicted CdG binding residues in HrcN were constructed. In vitro analyses of purified HrcN confirmed CdG binding and dodecamerisation for the wildtype. However, a G176A point-mutant of HrcN retained CdG binding but appeared to have compromised CdG-induced downstream oligomerisation. The effect of this mutation on virulence was therefore explored in vivo. Wildtype and mutant hrcN P. syringae pathovar tomato (Pto) DC3000 strains were infiltrated into Arabidopsis thaliana to evaluate disease phenotypes in planta. The G176A hrcN point-mutant exhibited a near-asymptomatic disease phenotype despite having a comparable bacterial load to the WT in A. thaliana Col-0. Disease symptoms returned in immunocompromised A. thaliana lines. The underlying mechanism was then explored. It was shown that a subset of tested effectors (HopAM1, HopAF1, and HopAA1-2) displayed compromised translocation rates for G176A hrcN compared to WT using an effector-CyaA reporter system in Pto. These effector proteins were shown to be important for disease symptom establishment by way of gene over-expression and gene deletion. Candidate interaction targets in the plant host were identified by co-immunoprecipitation. From this study, first indication that CdG binding to HrcN in Pto may lead to dodecamerisation was shown, and that this interaction is important for full virulence by enabling for efficient translocation of key effector proteins

Impact of a decade of successful antiretroviral therapy initiated at HIV-1 seroconversion on blood and mucosal reservoirs

Persistent reservoirs remain the major obstacles to achieve an HIV-1 cure. Prolonged early antiretroviral therapy (ART) may reduce the extent of reservoirs and allow for virological control after ART discontinuation. We compared HIV-1 reservoirs in a cross-sectional study using polymerase chain reaction-based techniques in blood and tissue of early-treated seroconverters, late-treated patients, ART-naïve seroconverters, and long-term non-progressors (LTNPs) who have spontaneous virological control without treatment. A decade of early ART reduced the total and integrated HIV-1 DNA levels compared with later treatment initiation, but not reaching the low levels found in LTNPs. Total HIV-1 DNA in rectal biopsies did not differ between cohorts. Importantly, lower viral transcription (HIV-1 unspliced RNA) and enhanced immune preservation (CD4/CD8), reminiscent of LTNPs, were found in early compared to late-treated patients. This suggests that early treatment is associated with some immunovirological features of LTNPs that may improve the outcome of future interventions aimed at a functional cure

Upconversion channels in Er3+:ZBLALiP fluoride glass microspheres

We present results on the realization of a multicolour microspherical glass light source fabricated from the erbium doped fluoride glass ZBLALiP. Whispering gallery mode lasing and upconversion processes give rise to laser and fluorescent emissions at multiple wavelengths from the ultraviolet to the infrared. Thirteen discrete emissions ranging from 320 to 849 nm have been observed in the upconversion spectrum. A Judd-Ofelt analysis was performed to calculate the radiative properties of Er3+:ZBLALiP microspheres, including the radiative transition probabilities, the electric dipole strengths, the branching ratios and the radiative lifetimes of the transitions involved. We have also identified the primary processes responsible for the generation of the observed wavelengths and have shown that this material has an improved range of emissions over other erbium doped fluoride glasses

Phantom Undulations: Remote Physiological Sensing in Abstract Installation Works

Phantom Undulations is a mixed-media work in which an artist’s physiological data is being used remotely to manipulate the sounds and visuals of an abstract artifact in a gallery setting. This work relies heavily on the concept of showing the artist’s presence or liveness in an abstract and remote manner through changes in the harmony, rhythm, and timbre of a loosely structured soundscape as well as the physical appearance of the artifact. We propose a method of utilizing real time physiological sensing data through a custom built sensing wristband and accompanying software. This system reads the physiological data of the artist and sends it to the Internet, where it can be received by the artifact anywhere on Earth. In addition to the artist’s physiological data, we also offer a way for the audience to incorporate their own data into the work via several sensing wristbands which will accompany the artifact. Through this collaborative process, we wish to invite the audience to join the artist in manipulating the sonic and visual characteristics of this artifact and create a contrapuntally fluid and responsive musical experience

Innermost Echoes: Integrating Real-Time Physiology into Live Music Performances

In this paper, we propose a method for utilizing musical artifacts and physiological data as a means for creating a new form of live music experience that is rooted in the physiology of the perform- ers and audience members. By utilizing physiological data (namely Electrodermal Activity (EDA) and Heart Rate Variability (HRV)) and applying this data to musical artifacts including a robotic koto (a traditional 13-string Japanese instrument fitted with solenoids and linear actuators), a Eurorack synthesizer, and Max/MSP software, we aim to develop a new form of semi-improvisational and signif- icantly indeterminate performance practice. It has since evolved into a multi-modal methodology which honors improvisational performance practices and utilizes physiological data which of- fers both performers and audiences an ever-changing and intimate experience. In our first exploratory phase, we focused on the development of a means for controlling a bespoke robotic koto in conjunction with a Eurorack synthesizer system and Max/MSP software for controlling the incoming data. We integrated a reliance on physiological data to infuse a more directly human elements into this artifact system. This allows a significant portion of the decision-making to be directly controlled by the incoming physiological data in real-time, thereby affording a sense of performativity within this non-living system. Our aim is to continue the development of this method to strike a novel balance between intentionality and impromptu performative results

A heat-and-pull rig for fiber taper fabrication

We describe a reproducible method of fabricating adiabatic tapers with 3-4 micron diameter. The method is based on a heat-and-pull rig, whereby a CO2 laser is continuously scanned across a length of fiber that is being pulled synchronously. Our system relies on a CO2 mirror mounted on a geared stepper motor in order to scan the laser beam across the taper region. We show that this system offers a reliable alternative to more traditional rigs incorporating galvanometer scanners. We have routinely obtained transmission losses between 0.1 and 0.3 dB indicating the satisfactory production of adiabatic tapers. The operation of the rig is described in detail and an analysis on the produced tapers is provided. The flexibility of the rig is demonstrated by fabricating prolate dielectric microresonators using a microtapering technique. Such a rig is of interest to a range of fields that require tapered fiber fabrication such as microcavity-taper coupling, atom guiding along a tapered fiber, optical fiber sensing and the fabrication of fused biconical tapered couplers.Comment: 13 pages, 6 figures Submitted to Rev. Sci. Instru