Interfacing low-energy SAW nebulization with liquid chromatography-mass spectrometry for the analysis of biological samples

Soft ionization methods for the introduction of labile biomolecules into a mass spectrometer are of fundamental importance to biomolecular analysis. Previously, electrospray ionization (ESI) and matrix assisted laser desorption-ionization (MALDI) have been the main ionization methods used. Surface acoustic wave nebulization (SAWN) is a new technique that has been demonstrated to deposit less energy into ions upon ion formation and transfer for detection than other methods for sample introduction into a mass spectrometer (MS). Here we report the optimization and use of SAWN as a nebulization technique for the introduction of samples from a low flow of liquid, and the interfacing of SAWN with liquid chromatographic separation (LC) for the analysis of a protein digest. This demonstrates that SAWN can be a viable, low-energy alternative to ESI for the LC-MS analysis of proteomic samples.

Review on protection issues of low-voltage distribution network with multiple powerelectronic-converter-interfaced distribution energy resources

The realisation of an eventual low-voltage (LV) Smart Grid with a complete communication infrastructure is a gradual process. During this evolution the protection scheme of distribution networks should be continuously adapted and optimised to fit the protection and cost requirements at the time. This paper aims to review practices and research around the design of an effective, adaptive and economical distribution network protection scheme. The background of this topic is introduced and potential problems are defined from conventional protection theories and new Smart Grid technologies. Challenges are identified with possible solutions defined as a pathway to the ultimate flexible and reliable LV protection systems.

Energy conversion assessment of vacuum, slow and fast pyrolysis processes for low and high ash paper waste sludge

The performance of vacuum, slow and fast pyrolysis processes to transfer energy from the paper waste sludge (PWS) to liquid and solid products was compared. Paper waste sludges with low and high ash content (8.5 and 46.7 wt.%) were converted under optimised conditions for temperature and pellet size to maximise both product yields and energy content. Comparison of the gross energy conversions, as a combination of the bio-oil/tarry phase and char (ECsum), revealed that the fast pyrolysis performance was between 18.5% and 20.1% higher for the low ash PWS, and 18.4% and 36.5% higher for high ash PWS, when compared to the slow and vacuum pyrolysis processes respectively. For both PWSs, this finding was mainly attributed to higher production of condensable organic compounds and lower water yields during FP. The low ash PWS chars, fast pyrolysis bio-oils and vacuum pyrolysis tarry phase products had high calorific values (∼18-23 MJ kg-1) making them promising for energy applications. Considering the low calorific values of the chars from alternative pyrolysis processes (∼4-7 MJ kg-1), the high ash PWS should rather be converted to fast pyrolysis bio-oil to maximise the recovery of usable energy products.

Fabrication of Dense Non-Circular Nanomagnetic Device Arrays Using Self-Limiting Low-Energy Glow-Discharge Processing

We describe a low-energy glow-discharge process using reactive ion etching system that enables non-circular device patterns, such as squares or hexagons, to be formed from a precursor array of uniform circular openings in polymethyl methacrylate, PMMA, defined by electron beam lithography. This technique is of a particular interest for bit-patterned magnetic recording medium fabrication, where close packed square magnetic bits may improve its recording performance. The process and results of generating close packed square patterns by self-limiting low-energy glow-discharge are investigated. Dense magnetic arrays formed by electrochemical deposition of nickel over self-limiting formed molds are demonstrated.

Ecohydrological separation in wet, low energy northern environments? A preliminary assessment using different soil water extraction techniques

Funded by European Research Council ERC. Grant Number: project GA 335910 VEWA

Ecohydrological separation in wet, low energy northern environments? A preliminary assessment using different soil water extraction techniques

Funded by European Research Council ERC. Grant Number: project GA 335910 VEWA

Proposta de arquitetura para monitorização de parâmetros vitais com recurso à tecnologia Bluetooth Low Energy

Atualmente, com o crescimento exponencial das tecnologias de comunicação móveis, cada vez mais existe uma utilização generalizada de dispositivos móveis que adotam normas de última geração para redes de área corporal (BAN), como o Bluetooth Low Energy. Estas normas vieram revolucionar a monitorização de parâmetros vitais, permitindo que esta seja efetuada em qualquer lugar e momento e que ocorra uma redução do consumo energético. Se tivermos em consideração as doenças mais causadoras de morte, a tendência de envelhecimento da população e a dificuldade de acesso e acompanhamento médico por parte de pacientes com incapacidades, a monitorização remota de parâmetros vitais surge como um auxiliar clínico para um diagnóstico melhor, mais rápido e mais fiável. O presente projeto tem como objetivo especificar uma arquitetura para monitorização remota de parâmetros vitais no sentido de criar uma solução pronta a usar, simples, eficiente, segura, de baixo custo e compatível com dispositivos móveis de última geração. A monitorização remota será efetuada com recurso ao dispositivo móvel, que o paciente já possui, através de uma aplicação que atua como intermediária entre os sensores biofísicos que efetuam a recolha de dados vitais e a plataforma onde estes serão armazenados. Após o envio dos dados para a plataforma é possível o seu acesso pelos profissionais de saúde para que assim os tenham em consideração ao efetuar diagnósticos. Os testes realizados mostram a facilidade e simplicidade de utilização do sistema, fatores muito importantes, bem como a fiabilidade na leitura de parâmetros vitais.

Proposta de arquitetura para monitorização de parâmetros vitais com recurso à tecnologia Bluetooth Low Energy

Atualmente, com o crescimento exponencial das tecnologias de comunicação móveis, cada vez mais existe uma utilização generalizada de dispositivos móveis que adotam normas de última geração para redes de área corporal (BAN), como o Bluetooth Low Energy. Estas normas vieram revolucionar a monitorização de parâmetros vitais, permitindo que esta seja efetuada em qualquer lugar e momento e que ocorra uma redução do consumo energético. Se tivermos em consideração as doenças mais causadoras de morte, a tendência de envelhecimento da população e a dificuldade de acesso e acompanhamento médico por parte de pacientes com incapacidades, a monitorização remota de parâmetros vitais surge como um auxiliar clínico para um diagnóstico melhor, mais rápido e mais fiável. O presente projeto tem como objetivo especificar uma arquitetura para monitorização remota de parâmetros vitais no sentido de criar uma solução pronta a usar, simples, eficiente, segura, de baixo custo e compatível com dispositivos móveis de última geração. A monitorização remota será efetuada com recurso ao dispositivo móvel, que o paciente já possui, através de uma aplicação que atua como intermediária entre os sensores biofísicos que efetuam a recolha de dados vitais e a plataforma onde estes serão armazenados. Após o envio dos dados para a plataforma é possível o seu acesso pelos profissionais de saúde para que assim os tenham em consideração ao efetuar diagnósticos. Os testes realizados mostram a facilidade e simplicidade de utilização do sistema, fatores muito importantes, bem como a fiabilidade na leitura de parâmetros vitais.

Labour and Low Energy Buildings: the energy performance gap as Social Practice

Buildings are responsible for approximately 30% of EU end-use emissions (Bettgenhäuser , et al, 2009) and are at the forefront of efforts to meet emissions targets arising from their design, construction and operation. For the first time in its history, construction industry outputs must meet specific energy targets if planned reductions in greenhouse gas emissions are to be achieved through nearly zero energy buildings (nZEB) (EC, 2010) supported by on-site renewable heat and power. Where individual UK dwellings have been tested before occupation to assess whether they meet energy design criteria, the results indicate what is described as an ‘energy performance gap’, that is, energy use is almost always more than that specified. This leads to the conclusion that the performance gap is, inter alia, a function of the labour process and thus a function of social practice. Social practice theory, based on Schatzki’s model (2002), is utilised to explore the performance gap as a result of the changes demanded in the social practice of building initiated by new energy efficiency rules. The paper aims to open a discussion where failure in technical performance is addressed as a social phenomenon.

A laboratory study of water ice erosion by low-energy ions

Water ice covers the surface of various objects in the outer Solar system.Within the heliopause, surface ice is constantly bombarded and sputtered by energetic particles from the solar wind and magnetospheres. We report a laboratory investigation of the sputtering yield of water ice when irradiated at 10 K by 4 keV singly (13C+, N+, O+, Ar+) and doubly charged ions (13C2+, N2+, O2+). The experimental values for the sputtering yields are in good agreement with the prediction of a theoretical model. There is no significant difference in the yield for singly and doubly charged ions. Using these yields, we estimate the rate of water ice erosion in the outer Solar system objects due to solar wind sputtering. Temperature-programmed desorption of the ice after irradiation with 13C+ and 13C2+ demonstrated the formation of 13CO and 13CO2, with 13CO being the dominant formed species.

Investigations on selected chalcogenide glasses towards the realization of photonic devices

Among various optical sensing schemes, infrared spectroscopy is a powerful tool for detecting and determining the composition of complex organic samples since vibrational finger prints of all biomolecules and organic species are located in this window. This spectroscopic technique is simple, reliable, fast, non-destructive, cost-effective while having low sensitivity. Use of metallic nanoparticles in association with a good IR transparent sensing substrate, is one of the promising solutions to enhance the sensitivity. Chalcogenide glasses are promising substrate material because of their extended optical transmission window starting from the visible to the far infrared range up to 20 μm, high refractive index usually between 2 and 3 and high optical nonlinearity, which make them good candidates as IR sensors and optical ultrafast nonlinear devices. These glasses are favorable sensor materials for the infrared spectral range because of their high IR transparency to allow for low optical loss at wavelengths corresponding to the characteristic optical absorption bands of organic molecules, high refractive index for tight confinement of optical energy within the resonator structure, processibility into thin film form, chemical compatibility for adhesion of silver nano particles and thin films and resistance to the chemical environment to be sensed. Molecules adsorbed to silver island structures shows enhanced IR absorption spectra and the extent of enhancement is determined by many factors such as the size, density and morphology of silver structures, optical and dielectric properties of the substrate material etc.

What kind of expertise is needed for low energy construction

The construction industry is responsible for 40% of European Union (EU) end-use emissions but addressing this is problematic, as evident from the performance gap between design intention and on-site energy performance. There is a lack of the expertise needed for low energy construction (LEC) in the UK as the complex work processes involved require ‘energy literacy’ of all construction occupations, high qualification levels, broad occupational profiles, integrated teamworking, and good communication . This research identifies the obstacles to meeting these requirements, the nature of the expertise needed to break down occupational divisions and bridge those interfaces where the main heat losses occur, and the transition pathway implied. Obstacles include a decline in the level, breadth and quality of construction vocational education and training (VET), the lack of a learning infrastructure on sites, and a fragmented employment structure. To overcome these and develop enhanced understanding of LEC requires a transformation of the existing structure of VET provision and construction employment and a new curriculum based on a broader concept of agency and backed by rigorous enforcement of standards. This can be achieved through a radical transition pathway rather than market-based solutions to a low carbon future for the construction sector.

DNA damage induced by low energy electrons (LEEs)

Abstract : The major objective of our study is to investigate DNA damage induced by soft X-rays (1.5 keV) and low-energy electrons (˂ 30 eV) using a novel irradiation system created by Prof. Sanche’s group. Thin films of double-stranded DNA are deposited on either glass and tantalum substrates and irradiated under standard temperature and pressure surrounded by a N[subscript 2] environment. Base release (cytosine, thymine, adenine and guanine) and base modifications (8-oxo-7,8-dihydro -2’-deoxyguanosine, 5-hydroxymethyl-2’-deoxyuridine, 5-formyl-2’-deoxyuridine, 5,6-dihydrothymidine and 5,6-dihydro-2’-deoxy uridine) are analyzed and quantified by LC-MS/MS. Our results reveal larger damage yields in the sample deposited on tantalum than those on glass. This can be explained by an enhancement of damage due to low-energy electrons, which are emitted from the metal substrate. From a comparison of the yield of products, base release is the major type of damage especially for purine bases, which are 3-fold greater than base modifications. A proposed pathway leading to base release involves the formation of a transient negative ion (TNI) followed by dissociative electron attachment (DEA) at the N-g lycosidic bond. On the other hand, base modification products consist of two major types of chemical modifications, which include thymine methyl oxidation products that likely arises from DEA from the methyl group of thymine, and 5,6-dihydropyrimidine that can involve the initial addition of electrons, H atoms, or hydride ions to the 5,6-pyrimidine double bond.