193 research outputs found
Chave para a identificação das espécies de abóboras (Cucurbita, Cucurbitaceae) cultivadas no Brasil.
Metodologia para identificação taxonômica de espécies de abóboras cultivadas (Cucurbita maxima, Cucurbita moschata, Cucurbita pepo, Cucurbita ficifolia e Cucurbita argyrosperma) - As abóboras cultivadas pertencem a cinco diferentes espécies, as quais são conhecidas por uma grande diversidade de nomes populares, particulares ou em comum, que confundem a correta identificação taxonômica da espécie. A carência de chaves taxonômicas no Brasil para a identificação das espécies cultivadas de abóboras, e o fato de que a maioria das chaves disponíveis em outros idiomas permite apenas a determinação taxonômica das três espécies mais comumente cultivadas (C. maxima, C. moschata e C. pepo), dificultam o correto reconhecimento e aproveitamento do potencial que estas culturas podem oferecer. A identificação adequada das espécies é essencial para atividades rotineiras de coleta, conservação, caracterização e multiplicação de acessos em um banco de germoplasma, e crucial para o sucesso de cruzamentos em programas de melhoramento. Além disso, sem uma correta identificação das espécies é difícil obter informações relevantes sobre estes cultivos. Para auxiliar na determinação taxonômica, esta publicação apresenta três chaves complementares de identificação, amplamente ilustradas com fotografias dos acessos do Banco Ativo de Germoplasma de Cucurbitaceae da Embrapa Clima Temperado. A primeira chave foi elaborada para identificação com base em caracteres vegetativos, a segunda em características dos frutos e a terceira para a identificação através de sementes. A diversidade morfológica entre as espécies cultivadas de Cucurbita é notável e, por isso, sempre que possível, mais de uma destas chaves deve ser considerada para confirmar a determinação de uma espécie. As informações das chaves são complementadas pelas fotografias que mostram características importantes para a identificação das espécies.bitstream/item/33837/1/documento-197.pd
The role of patients in European Clinical Ethics Consultation
Clinical ethics committees and consultation services have existed in many European countries for over two decades. Many different modes of operation have emerged, each reflecting a particular health and socio-political context. As additional clinical ethics services become established, the role of patients and their relatives is attracting increased attention. In North America, patient involvement has been theoretically lauded and recommended by policy, but nevertheless is often neglected in practice.1 In Europe, this issue has not yet received a great deal of attention, although the importance of listening to the patient's voice has been recognized for some time.2 Despite this, patients have diverse involvement in European clinical ethics support. Patients or their relatives can, for example: be members of a clinical ethics committee; be notified when an ethics consultation is requested; or be involved in ethical deliberation to the same extent as clinicians. At the 4th International Conference on Clinical Ethics and Consultation,3 Professor Stella Reiter-Theil convened an expert panel to discuss: ‘Whether and how to involve patients and relatives in clinical ethics support’. Panellists from across Europe4 used a case study to engage in a lively and interactive discussion on the different approaches to patient involvement in clinical ethics consultation.This article was written by Dr Ainsley Newson during the time of her employment with the University of Bristol, UK (2006-2012). Self-archived in the Sydney eScholarship Repository with permission of Bristol University, Sept 2014
The role of patients in European Clinical Ethics Consultation
editorialClinical ethics committees and consultation services have existed in many European countries for over
two decades. Many different modes of operation have emerged, each reflecting a particular health and
socio-political context.
As additional clinical ethics services become established, the role of patients and their relatives is
attracting increased attention. In North America, patient involvement has been theoretically lauded and
recommended by policy, but nevertheless is often neglected in practice.1 In Europe, this issue has not
yet received a great deal of attention, although the importance of listening to the patient's voice has
been recognized for some time.2 Despite this, patients have diverse involvement in European clinical
ethics support. Patients or their relatives can, for example: be members of a clinical ethics committee; be
notified when an ethics consultation is requested; or be involved in ethical deliberation to the same
extent as clinicians.
At the 4th International Conference on Clinical Ethics and Consultation,3 Professor Stella Reiter-Theil
convened an expert panel to discuss: ‘Whether and how to involve patients and relatives in clinical ethics
support’. Panellists from across Europe4 used a case study to engage in a lively and interactive
discussion on the different approaches to patient involvement in clinical ethics consultation.This article was written by Dr Ainsley Newson during the time of her employment with the University of Bristol, UK (2006-2012). Self-archived in the Sydney eScholarship Repository with permission of Bristol University, Sept 2014
From the Hitchin section to opers through nonabelian Hodge
For a complex simple simply connected Lie group , and a compact Riemann surface , we consider two sorts of families of flat -connections over . Each family is determined by a point of the base of Hitchin's integrable system for . One family consists of -opers, and depends on . The other family is built from solutions of Hitchin's equations, and depends on . We show that in the scaling limit , , we have . This establishes and generalizes a conjecture formulated by Gaiotto
Quantum Attractor Flows
Motivated by the interpretation of the Ooguri-Strominger-Vafa conjecture as a
holographic correspondence in the mini-superspace approximation, we study the
radial quantization of stationary, spherically symmetric black holes in four
dimensions. A key ingredient is the classical equivalence between the radial
evolution equation and geodesic motion of a fiducial particle on the moduli
space M^*_3 of the three-dimensional theory after reduction along the time
direction. In the case of N=2 supergravity, M^*_3 is a para-quaternionic-Kahler
manifold; in this case, we show that BPS black holes correspond to a particular
class of geodesics which lift holomorphically to the twistor space Z of M^*_3,
and identify Z as the BPS phase space. We give a natural quantization of the
BPS phase space in terms of the sheaf cohomology of Z, and compute the exact
wave function of a BPS black hole with fixed electric and magnetic charges in
this framework. We comment on the relation to the topological string amplitude,
extensions to N>2 supergravity theories, and applications to automorphic black
hole partition functions.Comment: 43 pages, 6 figures; v2: typos and references added; v3: published
version, minor change
Clinical ethics consultation in Europe: A comparative and ethical review of the role of patients
Clinical ethics has developed significantly in Europe over the past 15 years and remains an evolving process. While sharing our experiences in different European settings, we were surprised to discover marked differences in our practice, especially regarding the position and role of patients. In this paper, we describe these differences, such as patient access to and participation or representation in ethics consults. We propose reasons to explain these differences, hypothesizing that they relate to the historic and sociocultural context of implementation of clinical ethics consultation services (Cecs), as well as the initial aims for which each structure was established. Then, we analyse those differences with common ethical arguments arising in patient involvement. We conclude that there is no unique model of best practice for patient involvement in clinical ethics, as far as Cecs reflect on how to deal with the challenging ethical issues raised by patient role and position.This article was written by Dr Ainsley Newson during the time of her employment with the University of Bristol, UK (2006-2012). Self-archived in the Sydney eScholarship Repository with permission of Bristol University, Sept 2014
D-instantons and twistors: some exact results
We present some results on instanton corrections to the hypermultiplet moduli
space in Calabi-Yau compactifications of Type II string theories. Previously,
using twistor methods, only a class of D-instantons (D2-instantons wrapping
A-cycles) was incorporated exactly and the rest was treated only linearly. We
go beyond the linear approximation and give a set of holomorphic functions
which, through a known procedure, capture the effect of D-instantons at all
orders. Moreover, we show that for a sector where all instanton charges have
vanishing symplectic invariant scalar product, the hypermultiplet metric can be
computed explicitly.Comment: 32 pages, 3 figures, uses JHEP3.cls; some changes in section 3.3.3;
corrected formula for the contact potentia
Twistors and Black Holes
Motivated by black hole physics in N=2, D=4 supergravity, we study the
geometry of quaternionic-Kahler manifolds M obtained by the c-map construction
from projective special Kahler manifolds M_s. Improving on earlier treatments,
we compute the Kahler potentials on the twistor space Z and Swann space S in
the complex coordinates adapted to the Heisenberg symmetries. The results bear
a simple relation to the Hesse potential \Sigma of the special Kahler manifold
M_s, and hence to the Bekenstein-Hawking entropy for BPS black holes. We
explicitly construct the ``covariant c-map'' and the ``twistor map'', which
relate real coordinates on M x CP^1 (resp. M x R^4/Z_2) to complex coordinates
on Z (resp. S). As applications, we solve for the general BPS geodesic motion
on M, and provide explicit integral formulae for the quaternionic Penrose
transform relating elements of H^1(Z,O(-k)) to massless fields on M annihilated
by first or second order differential operators. Finally, we compute the exact
radial wave function (in the supergravity approximation) for BPS black holes
with fixed electric and magnetic charges.Comment: 47 pages, v2: typos corrected, reference added, v3: minor change
Cubic Twistorial String Field Theory
Witten has recently proposed a string theory in twistor space whose
D-instanton contributions are conjectured to compute N=4 super-Yang-Mills
scattering amplitudes. An alternative string theory in twistor space was then
proposed whose open string tree amplitudes reproduce the D-instanton
computations of maximal degree in Witten's model.
In this paper, a cubic open string field theory action is constructed for
this alternative string in twistor space, and is shown to be invariant under
parity transformations which exchange MHV and googly amplitudes. Since the
string field theory action is gauge-invariant and reproduces the correct cubic
super-Yang-Mills interactions, it provides strong support for the conjecture
that the string theory correctly computes N-point super-Yang-Mills tree
amplitudes.Comment: 19+1 pages, 4+1 EPS figures, JHEP3 LaTeX; v2: minor corrections,
references added; v3: the final version published in JHEP with a new footnote
on the d=0 on-shell contributio
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