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Food Insecurity and Lived Experience of Students (FILES)
This paper provides evidence of the impact of Covid-19 on higher education students’ levels of food security and lived experiences. We surveyed higher education students, attending three universities in the UK and one in the USA, from 1st April to 30th April 2020, during the Covid-19 pandemic and after universities closed the majority of their buildings and ceased campus-based teaching. A total of 1,234 surveys were returned. The preliminary findings show that nearly 35% of students surveyed reported low or very low levels of food security and 41% of students were worried that their food would run out. We also found high levels of poor mental health and well-being; and mental health was associated with level of food security. The best predictor of the level of food security was students’ living arrangements during the Covid-19 pandemic. Students who were living on their own or with other students were more likely to experience low or very low levels of food insecurity compared to those students living with family members. The financial data collected show that many students relied on employment as their main source of income, and students are very worried about their current financial security. Furthermore, we found a relatively high reliance on ultra-processed foods as the main food type in students’ diets. The data from open-ended questions lend further support to the quantitative findings reported and provide further insight into students’ lived experiences. Finally, this paper concludes with key recommendations for policy makers, universities and student unions. (Submitted to the Education Select Committee Inquiry on The impact of COVID-19 on education and children’s services, 03 June 2020) FILES is a research collaboration involving a number of academics and student union officers from across England, Northern Ireland and the USA. The group’s key objective is to research food insecurity and lived experiences of students in Higher Education. Food insecurity has been explored in other populations, but no evidence has been presented that examines food insecurity and lived experiences of students in higher education following Covid-19 lockdown. Authors: Professor Greta Defeyter, Professor Paul Stretesky, Dr Mike Long, Dr Sinéad Furey, Dr Christian Reynolds, Dr Alyson Dodds, Dr Debbie Porteous, Dr Emily Mann, Mrs Christine Stretesky, Ms Anna Kemp, Mr James Fox, Mr Andrew McAnalle
MODIS time series contribution for the estimation of nutritional properties of alpine grassland
This is an Accepted Manuscript of an article published by Taylor & Francis in European Journal of Remote Sensing on 17th February 2017, available online: https://doi.org/10.5721/EuJRS20164936Despite the Normalised Difference Vegetation Index (NDVI) has been used to make predictions on forage quality, its relationship with bromatological field data has not been widely tested. This relationship was investigated in alpine grasslands of the Gran Paradiso National Park (Italian Alps). Predictive models were built using remotely sensed derived variables (NDVI and phenological information computed from MODIS) in combination with geo-morphometric data as predictors of measured biomass, crude protein, fibre and fibre digestibility, obtained from 142 grass samples collected within 19 experimental plots every two weeks during the whole 2012 growing season. The models were both cross-validated and validated on an independent dataset (112 samples collected during 2013). A good predictability ability was found for the estimation of most of the bromatological measures, with a considerable relative importance of remotely sensed derived predictors; instead, a direct use of NDVI values as a proxy of bromatological variables appeared not to be supported
Dynamical approach to spectator fragmentation in Au+Au reactions at 35 MeV/A
The characteristics of fragment emission in peripheral Au+Au
collisions 35 MeV/A are studied using the two clusterization approaches within
framework of \emph{quantum molecular dynamics} model. Our model calculations
using \emph{minimum spanning tree} (MST) algorithm and advanced clusterization
method namely \emph{simulated annealing clusterization algorithm} (SACA) showed
that fragment structure can be realized at an earlier time when spectators
contribute significantly toward the fragment production even at such a low
incident energy. Comparison of model predictions with experimental data reveals
that SACA method can nicely reproduce the fragment charge yields and mean
charge of the heaviest fragment. This reflects suitability of SACA method over
conventional clusterization techniques to investigate spectator matter
fragmentation in low energy domain.Comment: 6 pages, 5 figures, accepte
Dark Matter Model Selection and the ATIC/PPB-BETS anomaly
We argue that we may be able to sort out dark matter models in which
electrons are generated through the annihilation and/or decay of dark matter,
by using a fact that the initial energy spectrum is reflected in the cosmic-ray
electron flux observed at the Earth even after propagation through the galactic
magnetic field. To illustrate our idea we focus on three representative initial
spectra: (i)monochromatic (ii)flat and (iii)double-peak ones. We find that
those three cases result in significantly different energy spectra, which may
be probed by the Fermi satellite in operation or an up-coming cosmic-ray
detector such as CALET.Comment: 19 pages, 8 figure
The Leptonic Higgs as a Messenger of Dark Matter
We propose that the leptonic cosmic ray signals seen by PAMELA and ATIC
result from the annihilation or decay of dark matter particles via states of a
leptonic Higgs doublet to leptons, linking cosmic ray signals of dark
matter to LHC signals of the Higgs sector. The states of the leptonic Higgs
doublet are lighter than about 200 GeV, yielding large and
event rates at the LHC. Simple models are
given for the dark matter particle and its interactions with the leptonic
Higgs, for cosmic ray signals arising from both annihilations and decays in the
galactic halo. For the case of annihilations, cosmic photon and neutrino
signals are on the verge of discovery.Comment: 34 pages, 9 figures, minor typos corrected, references adde
Atmospheric ammonia assessments on six designated sites in Northern Ireland. Report 2: June 2020 – May 2022
Prepared between the UK Centre for Ecology & Hydrology (UKCEH) and the Department of Agriculture, Environment and Rural Affairs (DAERA) Northern Ireland Environment Agency (NIEA). Atmospheric ammonia (NH3) gas concentrations were monitored on six designated sites of international and national importance (Special Areas of Conservation, SAC and Areas of Special Scientific Interest (ASSI)) across Northern Ireland, to assess threats from atmospheric nitrogen inputs. A total of 37 NH3 monitoring points were established, with between 4 and 9 monitoring points on each of the six designated sites, depending on the size and complexity of each site. Monitoring was carried out at monthly intervals, with continuous time-integrated measurements made with passive UKCEH ALPHA® samplers. This report presents monthly NH3 measurements from two complete years of monitoring, between June 2020 and May 2022. Monthly measurements were aggregated to estimate annual average concentrations for the assessment of critical levels exceedance (annual thresholds). The monthly monitoring periods also enabled the construction of seasonal profiles across the sites, which is helpful for identifying peak emission periods as well as likely source types (for example, slurry spreading activities during spring
Coupled Boltzmann calculation of mixed axion/neutralino cold dark matter production in the early universe
We calculate the relic abundance of mixed axion/neutralino cold dark matter
which arises in R-parity conserving supersymmetric (SUSY) models wherein the
strong CP problem is solved by the Peccei-Quinn (PQ) mechanism with a
concommitant axion/saxion/axino supermultiplet. By numerically solving the
coupled Boltzmann equations, we include the combined effects of 1. thermal
axino production with cascade decays to a neutralino LSP, 2. thermal saxion
production and production via coherent oscillations along with cascade decays
and entropy injection, 3. thermal neutralino production and re-annihilation
after both axino and saxion decays, 4. gravitino production and decay and 5.
axion production both thermally and via oscillations. For SUSY models with too
high a standard neutralino thermal abundance, we find the combined effect of
SUSY PQ particles is not enough to lower the neutralino abundance down to its
measured value, while at the same time respecting bounds on late-decaying
neutral particles from BBN. However, models with a standard neutralino
underabundance can now be allowed with either neutralino or axion domination of
dark matter, and furthermore, these models can allow the PQ breaking scale f_a
to be pushed up into the 10^{14}-10^{15} GeV range, which is where it is
typically expected to be in string theory models.Comment: 26 pages with 12 .eps figure
The Residual Stress Relaxation Behavior of Weldments During Cyclic Loading
Accurate measurement of residual stress is necessary to obtain reliable predictions of fatigue lifetime and enable estimation of time-to-facture for any given stress level. In this article, relaxation of welding residual stresses as a function of cyclic loading was documented on three common steels: AISI 1008, ASTM A572, and AISI 4142. Welded specimens were subjected to cyclic bending (R = 0.1) at different applied stresses, and the residual stress relaxation existing near the welds was measured as a function of cycles. The steels exhibited very different stress relaxation behaviors during cyclic loadings, which can be related to the differences in the microstructures of the specimens. A phenomenological model, which treats dislocation motion during cyclic loading as being analogous to creep of dislocations, is proposed for estimation of the residual stress relaxation
PAMELA/ATIC anomaly from the meta-stable extra dark matter component and the leptophilic Yukawa interaction
We present a supersymmetric model with two dark matter (DM) components
explaining the galactic positron excess observed by PAMELA/HEAT and
ATIC/PPB-BETS: One is the conventional (bino-like) lightest supersymmetric
particle (LSP) \chi, and the other is a TeV scale meta-stable neutral singlet
N_D, which is a Dirac fermion (N,N^c). In this model, N_D decays dominantly
into \chi e^+e^- through an R parity preserving dimension 6 operator with the
life time \tau_N\sim 10^{26} sec. We introduce a pair of vector-like superheavy
SU(2) lepton doublets (L,L^c) and lepton singlets (E,E^c). The dimension 6
operator leading to the N_D decay is generated from the leptophilic Yukawa
interactions by W\supset Ne^cE+Lh_dE^c+m_{3/2}l_1L^c with the dimensionless
couplings of order unity, and the gauge interaction by {\cal L}\supset \sqrt{2}
g'\tilde{e}^{c*}e^c\chi + h.c. The superheavy masses of the vector-like leptons
(M_L, M_E\sim 10^{16} GeV) are responsible for the longevity of N_D. The low
energy field spectrum in this model is just the MSSM fields and N_D. Even for
the case that the portion of N_D is much smaller than that of \chi in the total
DM density [{\cal O}(10^{-10}) \lesssim n_{N_D}/n_\chi], the observed positron
excess can be explained by adopting relatively lighter masses of the
vector-like leptons (10^{13} GeV \lesssim M_{L,E} \lesssim 10^{16} GeV). The
smallness of the electron mass is also explained. This model is easily embedded
in the flipped SU(5) grand unification, which is a leptophilic unified theory.Comment: 12 pages, published versio
Heavy Quarks and Heavy Quarkonia as Tests of Thermalization
We present here a brief summary of new results on heavy quarks and heavy
quarkonia from the PHENIX experiment as presented at the "Quark Gluon Plasma
Thermalization" Workshop in Vienna, Austria in August 2005, directly following
the International Quark Matter Conference in Hungary.Comment: 8 pages, 5 figures, Quark Gluon Plasma Thermalization Workshop
(Vienna August 2005) Proceeding
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