4,304 research outputs found
Human resourcing in academic libraries : the 'lady librarian', the call for flexible staff and the need to be counted
This paper reports on a recent set of research findings into human resource (HR) deployment in academic, college and national libraries in the UK and Ireland by selectively summarising these findings. The recommendations are that libraries should make available for comparison by others not only their library service provision, i.e. opening hours, but also staff provision, i.e. staffing numbers and demographics and staff deployment, with a view to benchmarking levels of flexibility. This work highlights the lack of existing benchmarking facilities in UK universities and colleges of higher education, relating to HR deployment in libraries, and recommends that Sconul extends the existing data collection in its Annual Statistical return to include this HR area
Gene expression analysis of bovine embryonic disc, trophoblast and parietal hypoblast at the start of gastrulation
In cattle early gastrulation-stage embryos (Stage 5), four tissues can be discerned: (i) the top layer of the embryonic disc consisting of embryonic ectoderm (EmE); (ii) the bottom layer of the disc consisting of mesoderm, endoderm and visceral hypoblast (MEH); (iii) the trophoblast (TB); and (iv) the parietal hypoblast. We performed microsurgery followed by RNA-seq to analyse the transcriptome of these four tissues as well as a developmentally earlier pre-gastrulation embryonic disc. The cattle EmE transcriptome was similar at Stages 4 and 5, characterised by the OCT4/SOX2/NANOG pluripotency network. Expression of genes associated with primordial germ cells suggest their presence in the EmE tissue at these stages. Anterior visceral hypoblast genes were transcribed in the Stage 4 disc, but no longer by Stage 5. The Stage 5 MEH layer was equally similar to mouse embryonic and extraembryonic visceral endoderm. Our data suggest that the first mesoderm to invaginate in cattle embryos is fated to become extraembryonic. TGFβ, FGF, VEGF, PDGFA, IGF2, IHH and WNT signals and receptors were expressed, however the representative members of the FGF families differed from that seen in equivalent tissues of mouse embryos. The TB transcriptome was unique and differed significantly from that of mice. FGF signalling in the TB may be autocrine with both FGFR2 and FGF2 expressed. Our data revealed a range of potential inter-tissue interactions, highlighted significant differences in early development between mice and cattle and yielded insight into the developmental events occurring at the start of gastrulation
Detection of solvents using a distributed fibre optic sensor
A fibre optic sensor that is capable of distributed detection of liquid solvents is presented. Sensor interrogation using optical time domain reflectometry (OTDR) provides the capability of locating solvent spills to a precision of ±2 m over a total sensor length that may extend to 20 km
Modelling future patterns of urbanization, residential energy use and greenhouse gas emissions in Dar es Salaam with the Shared Socio-Economic Pathways
This paper presents three scenarios of urban growth, energy use and greenhouse gas (GHG) emissions in Dar es Salaam using narratives that are consistent with the Shared Socio-Economic Pathways (SSPs). We estimate residential energy demand and GHG emissions from 2015 to 2050 for household activities (including upstream electricity generation) and passenger (road) transport (Scopes 1 and 2). We project that by 2050, Dar es Salaam's total residential emissions would increase from 1,400 ktCO2e (in 2015) up to 25,000–33,000 ktCO2e (SSP1); 11,000–19,000 ktCO2e (SSP2); and 5,700–11,000 ktCO2e (SSP3), with ranges corresponding to different assumptions about household size. This correlates with an increase in per capita emissions from 0.2 tCO2e in 2015 to 1.5–2 tCO2e (SSP1); 0.7–1.3 tCO2e (SSP2); and 0.5–0.9 tCO2e (SSP3). Higher emissions in SSP1 (the sustainability scenario) are driven by a higher urban population in 2050 and increased energy access and electricity consumption. Through aggressive GHG mitigation policies focused on decarbonization of the electricity sector and road transport, total emissions under SSP1 can be reduced by ∼66% in 2050. Study insights aim to inform policies that identify and capture synergies between low-GHG investments and broader socio-economic development goals in Sub-Saharan African cities
Spin-Dependent Tunneling of Single Electrons into an Empty Quantum Dot
Using real-time charge sensing and gate pulsing techniques we measure the
ratio of the rates for tunneling into the excited and ground spin states of a
single-electron AlGaAs/GaAs quantum dot in a parallel magnetic field. We find
that the ratio decreases with increasing magnetic field until tunneling into
the excited spin state is completely suppressed. However, we find that by
adjusting the voltages on the surface gates to change the orbital configuration
of the dot we can restore tunneling into the excited spin state and that the
ratio reaches a maximum when the dot is symmetric.Comment: 4 pages, 3 figure
Continuous-wave Raman laser pumped within a semiconductor disk laser cavity
A KGd(WO4)(2) Raman laser was pumped within the cavity of a cw diode-pumped InGaAs semiconductor disk laser (SDL). The Raman laser threshold was reached for 5: 6W of absorbed diode pump power, and output power up to 0.8W at 1143nm, with optical conversion efficiency of 7.5% with respect to the absorbed diode pump power, was demonstrated. Tuning the SDL resulted in tuning of the Raman laser output between 1133 and 1157nm
Electrical control of spin relaxation in a quantum dot
We demonstrate electrical control of the spin relaxation time T_1 between
Zeeman split spin states of a single electron in a lateral quantum dot. We find
that relaxation is mediated by the spin-orbit interaction, and by manipulating
the orbital states of the dot using gate voltages we vary the relaxation rate
W= (T_1)^-1 by over an order of magnitude. The dependence of W on orbital
confinement agrees with theoretical predictions and from these data we extract
the spin-orbit length. We also measure the dependence of W on magnetic field
and demonstrate that spin-orbit mediated coupling to phonons is the dominant
relaxation mechanism down to 1T, where T_1 exceeds 1s.Comment: 4 pages, 3 figure
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