47 research outputs found
Thresholds of biodiversity and ecosystem function in a forest ecosystem undergoing dieback
Ecological thresholds, which represent points of rapid change in ecological properties, are of major scientific and societal concern. However, very little research has focused on empirically testing the occurrence of thresholds in temperate terrestrial ecosystems. To address this knowledge gap, we tested whether a number of biodiversity, ecosystem functions and ecosystem condition metrics exhibited thresholds in response to a gradient of forest dieback, measured as changes in basal area of living trees relative to areas that lacked recent dieback. The gradient of dieback was sampled using 12 replicate study areas in a temperate forest ecosystem. Our results provide novel evidence of several thresholds in biodiversity (namely species richness of ectomycorrhizal fungi, epiphytic lichen and ground flora); for ecological condition (e.g. sward height, palatable seedling abundance) and a single threshold
for ecosystem function (i.e. soil respiration rate). Mechanisms for these thresholds are explored. As climate-induced forest dieback is increasing worldwide, both in scale and speed, these results imply that threshold responses may become increasingly widespread
Inclusive jet cross sections and dijet correlations in photoproduction at HERA
Inclusive jet cross sections in photoproduction for events containing a
meson have been measured with the ZEUS detector at HERA using an integrated
luminosity of . The events were required to have a
virtuality of the incoming photon, , of less than 1 GeV, and a
photon-proton centre-of-mass energy in the range . The measurements are compared with next-to-leading-order (NLO) QCD
calculations. Good agreement is found with the NLO calculations over most of
the measured kinematic region. Requiring a second jet in the event allowed a
more detailed comparison with QCD calculations. The measured dijet cross
sections are also compared to Monte Carlo (MC) models which incorporate
leading-order matrix elements followed by parton showers and hadronisation. The
NLO QCD predictions are in general agreement with the data although differences
have been isolated to regions where contributions from higher orders are
expected to be significant. The MC models give a better description than the
NLO predictions of the shape of the measured cross sections.Comment: 43 pages, 12 figures, charm jets ZEU
Dissociation of virtual photons in events with a leading proton at HERA
The ZEUS detector has been used to study dissociation of virtual photons in
events with a leading proton, gamma^* p -> X p, in e^+p collisions at HERA. The
data cover photon virtualities in two ranges, 0.03<Q^2<0.60 GeV^2 and 2<Q^2<100
GeV^2, with M_X>1.5 GeV, where M_X is the mass of the hadronic final state, X.
Events were required to have a leading proton, detected in the ZEUS leading
proton spectrometer, carrying at least 90% of the incoming proton energy. The
cross section is presented as a function of t, the squared four-momentum
transfer at the proton vertex, Phi, the azimuthal angle between the positron
scattering plane and the proton scattering plane, and Q^2. The data are
presented in terms of the diffractive structure function, F_2^D(3). A
next-to-leading-order QCD fit to the higher-Q^2 data set and to previously
published diffractive charm production data is presented
Patents and Industrialisation. An Historical Overview of the British Case, 1624-1907
A Report to the Strategic Advisory Board on Intellectual Property Policy (SABIP), U
Increased Incidence of Vestibular Disorders in Patients With SARS-CoV-2
OBJECTIVE: Determine the incidence of vestibular disorders in patients with SARS-CoV-2 compared to the control population.
STUDY DESIGN: Retrospective.
SETTING: Clinical data in the National COVID Cohort Collaborative database (N3C).
METHODS: Deidentified patient data from the National COVID Cohort Collaborative database (N3C) were queried based on variant peak prevalence (untyped, alpha, delta, omicron 21K, and omicron 23A) from covariants.org to retrospectively analyze the incidence of vestibular disorders in patients with SARS-CoV-2 compared to control population, consisting of patients without documented evidence of COVID infection during the same period.
RESULTS: Patients testing positive for COVID-19 were significantly more likely to have a vestibular disorder compared to the control population. Compared to control patients, the odds ratio of vestibular disorders was significantly elevated in patients with untyped (odds ratio [OR], 2.39; confidence intervals [CI], 2.29-2.50;
CONCLUSIONS: The incidence of vestibular disorders differed between COVID-19 variants and was significantly elevated in COVID-19-positive patients compared to the control population. These findings have implications for patient counseling and further research is needed to discern the long-term effects of these findings
Study of deep inelastic inclusive and diffractive scattering with the ZEUS forward plug calorimeter
Deep inelastic scattering and its diffractive component, ep -> e'gamma*p
->e'XN, have been studied at HERA with the ZEUS detector using an integrated
luminosity of 4.2 pb-1. The measurement covers a wide range in the gamma*p c.m.
energy W (37 - 245 GeV), photon virtuality Q2 (2.2 - 80 GeV2) and mass Mx. The
diffractive cross section for Mx > 2 GeV rises strongly with W; the rise is
steeper with increasing Q2. The latter observation excludes the description of
diffractive deep inelastic scattering in terms of the exchange of a single
Pomeron. The ratio of diffractive to total cross section is constant as a
function of W, in contradiction to the expectation of Regge phenomenology
combined with a naive extension of the optical theorem to gamma*p scattering.
Above Mx of 8 GeV, the ratio is flat with Q2, indicating a leading-twist
behaviour of the diffractive cross section. The data are also presented in
terms of the diffractive structure function, F2D(3)(beta,xpom,Q2), of the
proton. For fixed beta, the Q2 dependence of xpom F2D(3) changes with xpom in
violation of Regge factorisation. For fixed xpom, xpom F2D(3) rises as beta ->
0, the rise accelerating with increasing Q2. These positive scaling violations
suggest substantial contributions of perturbative effects in the diffractive
DIS cross section.Comment: 87 pages, 25 figure
Schumpeter and Venture Finance: Radical Theorist, Broke Investor and Enigmatic Teacher
Schumpeter's relation to venture finance constitutes a fascinating yet so far unacknowledged chapter of his biography and financial history. Presenting new historical evidence and pointing out connections that have so far escaped attention, we first discuss Schumpeter's venture theory of money and banking, then his personal history as a broke investor in Vienna, and finally his influence on the emerging venture industry during his later years at Harvard. We show how the theoretical vision inspired his failed effort as a venture investor in the 1920s, and provided a powerful intellectual frame for the later development of venture finance in the 1940s
Private banking in Europe : rise, retreat, and resurgence
Private bankers have been defined as owner-managers of their bank, irrespective of their type of activity, which could be in any field of banking, sometimes in conjunction with another one, especially commerce in the earlier periods. Analysing the experiences of European private bankers from the early modern period to the early twenty-first century, this book starts by examining the slow emergence of specialist private bankers, largely from amongst those who provided commercial credit. This initial consideration culminates in a focus upon the roles that they played, both during the onset of the continent's industrialization, and in orchestrating the finances of the emerging world economy. Its second theme is private banking's waning importance with the rise of joint-stock competitors, which became increasingly apparent in Britain during the mid-nineteenth century, and elsewhere within Europe some decades later. Lastly, attention is paid to the decline of private bankers in the twentieth century -a protracted and uneven decline, combined with the persistence and even the enduring success of some segments of the profession. It concludes with the revival of private banking in the late twentieth century as a response to the development of a new market - the management of personal wealth.-- Introduction
-- 1: Instruments, institutions, centres and networks: developing the structural framework, c.1300-1700
-- 2: Public and private markets for capital and credit, 1688-1793
-- 3: War and economic transformation, 1793-185
-- 4: Golden age, 1815-1870
-- 5: The onset of the corporate economy, 1870-1914
-- 6: Indian summer, 1914-1931
-- 7: Decline and renaissance, 1931-c.2000
-- Conclusio