Species Richness Increased Yield Stability in Intensively Managed Grasslands Subjected to Experimental Drought

Climate change is expected to cause an increase in the frequency and intensity of drought events. Over two years we investigated the effects of experimentally imposed drought on intensively managed grassland communities (5 m x 6 m plots) of varying richness (1, 2 and 4 species), and comprising four species (Lolium perenne L., Cichorium intybus L., Trifolium repens L., Trifolium pratense L.). In each year a summer drought period of nine weeks with complete exclusion of precipitation was simulated, inducing severe drought stress at Reckenholz (Zürich, Switzerland), and extreme drought stress at Wexford (Ireland). Mean yield and plot-to-plot variance of yield were measured across harvests during drought and after a subsequent post-drought recovery period. At both sites, there was a positive relationship between species richness and yield under both the rainfed control conditions and under drought. At both sites, four-species communities had lower plot-to-plot variance of yield compared to monoculture or two-species communities under both rainfed (-49% smaller standard deviation) and drought conditions (-24%), which demonstrates higher yield stability in four-species communities. At the Swiss but not the Irish site, a high degree of species asynchrony could be identified as a mechanism underlying increased temporal stability in four-species communities

Hybrid GaN microLED platform for fluorescence sensing

A hybrid GaN μLED platform developed for wearable illumination is adapted here for fluorescence sensing. Proof-of-principle detection of colloidal quantum dots down to 80 pM using a mobile phone camera is demonstrate

Design of a wearable LED based device for phototherapy applications

Phototherapy with UV or visible wavelengths is used to treat skin disorders such as psoriasis, eczema and vitiligo. Traditionally, phototherapy is carried out in a clinical environment and utilises large fluorescent lamps. These are now being replaced with more efficient light-emitting diodes (LEDs), a trend that is set to contin ue thanks to the progress of LED technology. LEDs are also facilitating the emergence of at-home devices to improve patient convenience and decrease demand on the healt hcare system [1]. Current at-home devices consist of rigid LED arrays, which limits their conformability and produces non-uniform light distribution over the treatment area, in turn limiting their efficacy and wearability [2]. As a solution to this problem, we are engineering a flexible light therapy device that combines LEDs and a sub-mm-thick polydimethylsiloxane (PDMS) light sheet in an edge-lit configuration

Wearable LED-based device for phototherapy applications

Phototherapy with UVA/B or visible wavelengths is used to treat skin disorders such as psoriasis, eczema and vitiligo. Traditionally, phototherapy is carried out in a clinical environment and utilises large fluorescent lamps. hese are now being replaced with more efficient light-emitting diodes (LEDs), a trend that is set to continue thanks to the progress of UV LED technology. LEDs are also facilitating the emergence of at-home devices to improve patient convenience and decrease de mand on the healthcare system [1] . Current at-home devices consist of inflexible LED arrays, which limits their conformability and produces non-uniform light distribution over the treatment area, in turn limiting their efficacy and wearability [2] . As a solution to this problem, we are engineering a flexible light therapy device that combines LEDs and a sub-mm-thick polydimethylsiloxane (PDMS) light sheet in an edge-lit configuration. PDMS has previously been shown as an effective flexible light guide [3 ]; its high transparency from 290 nm upwards and its biocompatibility make it an ideal substrate for a wearable phototherapy device. We will describe the effect of coupling LEDs to our PDMS sheet and discuss design strategies for efficient and uniform light extraction to the treatment area. The PDMS acts as a waveguide and the light diffused through the top surface of the sheet is measured as irradiance (μW/cm2). By adding scattering particles for light extraction a 10-fold enhancement in irradiance has been demonstrated. Utilising a UV LED (385 nm) at an optical power of 25 mW, this approach produces a uniform emission of 140 μW/cm2 over a treatment area of 225 mm2 ( fig. 1). Simulations have shown that the addition of diffractive patterns to the sheet also produces an increased uniform emission

Hybrid GaN LED/elastomer membrane for uniform area illumination

A mechanically-flexible device for uniform area illumination is presented. The device consists of a 1mm-thick elastomeric membrane edge-lit by a GaN LED. Homogenous irradiance above 0.13 mW/cm2 at 450 nm over a 2.5 cm2 area is reported. Performance improvements, scalability and operation at other wavelengths are discussed

Deletion of the gabra2 gene results in hypersensitivity to the acute effects of ethanol but does not alter ethanol self administration

Human genetic studies have suggested that polymorphisms of the GABRA2 gene encoding the GABA(A) α2-subunit are associated with ethanol dependence. Variations in this gene also convey sensitivity to the subjective effects of ethanol, indicating a role in mediating ethanol-related behaviours. We therefore investigated the consequences of deleting the α2-subunit on the ataxic and rewarding properties of ethanol in mice. Ataxic and sedative effects of ethanol were explored in GABA(A) α2-subunit wildtype (WT) and knockout (KO) mice using a Rotarod apparatus, wire hang and the duration of loss of righting reflex. Following training, KO mice showed shorter latencies to fall than WT littermates under ethanol (2 g/kg i.p.) in both Rotarod and wire hang tests. After administration of ethanol (3.5 g/kg i.p.), KO mice took longer to regain the righting reflex than WT mice. To ensure the acute effects are not due to the gabra2 deletion affecting pharmacokinetics, blood ethanol concentrations were measured at 20 minute intervals after acute administration (2 g/kg i.p.), and did not differ between genotypes. To investigate ethanol's rewarding properties, WT and KO mice were trained to lever press to receive increasing concentrations of ethanol on an FR4 schedule of reinforcement. Both WT and KO mice self-administered ethanol at similar rates, with no differences in the numbers of reinforcers earned. These data indicate a protective role for α2-subunits, against the acute sedative and ataxic effects of ethanol. However, no change was observed in ethanol self administration, suggesting the rewarding effects of ethanol remain unchange

A comparative framework: how broadly applicable is a 'rigorous' critical junctures framework?

The paper tests Hogan and Doyle's (2007, 2008) framework for examining critical junctures. This framework sought to incorporate the concept of ideational change in understanding critical junctures. Until its development, frameworks utilized in identifying critical junctures were subjective, seeking only to identify crisis, and subsequent policy changes, arguing that one invariably led to the other, as both occurred around the same time. Hogan and Doyle (2007, 2008) hypothesized ideational change as an intermediating variable in their framework, determining if, and when, a crisis leads to radical policy change. Here we test this framework on cases similar to, but different from, those employed in developing the exemplar. This will enable us determine whether the framework's relegation of ideational change to a condition of crisis holds, or, if ideational change has more importance than is ascribed to it by this framework. This will also enable us determined if the framework itself is robust, and fit for the purposes it was designed to perform — identifying the nature of policy change

Jejunum free flap in hypopharynx reconstruction: Case series

BACKGROUND: Surgical treatment of hypopharyngeal cancers with extension to the retrocricoid region generally requires a circumferential pharyngolaryngectomy followed by a reconstruction of the removed segment of the upper digestive tract. Historically, many techniques have been used in order to achieve a safe and functional reconstruction. Jejunum interposition is generally considered the best reconstructive technique. METHODS: This study examines the details of the surgical technique, the complications, the oncological and the functional results in a series of 29 consecutive patients submitted to circumferential pharyngoesophageal resection for advanced hypopharyngeal cancer followed by reconstruction with a free flap of jejunum. RESULTS: Three of the transplants failed because of venous thrombosis. The overall success rate was 90%. There were no general complications. A good swallowing has been preserved in all our patients. All our patients where a phonatory prosthesis was positioned (20/29) were able to achieve speech following speech therapy and all were satisfied with their own capacity to communicate. CONCLUSIONS: The prognosis of hypopharyngeal tumours (18–40% at 5 years) remains poor, but jejunum autografts are being shown to be an excellent choice for the reconstruction of the cervical hypopharyngo-oesophagus offering the patient fast rehabilitation and a reasonable quality of survival. Our experience confirm that this kind of reconstruction is safe with a good results in improving oncologic controls and restoring a good quality of life