1,337 research outputs found
The importance of Good Clinical Practice guidelines and its role in clinical trials
Good Clinical Practice (GCP) is an international ethical and scientific quality standard for the design, conduct, performance, monitoring, auditing, recording, analyses and reporting of clinical trials. It also serves to protect the rights, integrity and confidentiality of trial subjects. It is very important to understand the background of the formation of the ICH-GCP guidelines as this, in itself, explains the reasons and the need for doing so. In this paper, we address the historical background and the events that led up to the formation of these guidelines. Today, the ICH-GCP guidelines are used in clinical trials throughout the globe with the main aim of protecting and preserving human rights
Unfavorable Infant Feeding Practices in East Lombok Have Not Yet Changed Much in the Last Decade (Praktik Pemberian Makan Bayi Yang Tidak Tepat Belum Banyak Mengalami Perubahan Dalam Satu Dekade Terakhir Di Lombok Timur)
Background: One of the districts that haven't reached the national nutrition recovery target was East Lombok, the prevalence of underweight among under two children was 25.5 percent. One of the underlying causes of under-nutrition is inappropriate feeding practices that occur during the first year of life. Several factors lies behind these practices, such as experiences, family demands, socio-economic circumstances, and cultural beliefs. Objective: To explore the infant feeding (breastfeeding and complementary feeding) practices among 9-11 month infants in East Lombok. Methods: This cross-sectional study use qualitative method. Four Group Interview with the mothers of 9-11 month infants were conducted. Confirmation was done from Group Interview with the cadres, interview with local health officers and observation from study site. Analysis was done by making contrast, comparison or themes emerged from the data. Results: This study revealed that the infant feeding practices still haven't optimal as indicated by low exclusive breastfeeding practices for 6th month, pre-lacteal feeding and the consumption of pre-masticated foods (“papah”) still commonly happen in East Lombok. Furthermore, the early introduction of complementary food and less frequency of meals and snacks a day also still practiced. The hygiene practices also still have to be considered where the consumption of unboiled water (“air nyet”) among infants still familiar in this area. Comparing to several studies have been conducted, these unfavorable infant feeding practices in East Lombok have not yet changed much in the last decade. Conclusion: Most of the infant feeding practices in East Lombok were haven't optimal. Recommendation: Local-specific nutrition education was needed with the involvement of religious leader in the community in delivering the messages. Other community channel (like arisan or pertemuan kampung) was also recommended to deliver the messages
Investigating the early pottery Neolithic of northern Syria:New evidence from Tell Sabi Abyad
Sexual selection and population divergence III : interspecific and intraspecific variation in mating signals
Funding: Orthopterists' Society, Natural Environment Research Council (Grant Number(s): NE/G00949X/1, NE/G014906/1, NE/L011255/1), ARC (Grant Number(s): DP180101708).A major challenge for studying the role of sexual selection in divergence and speciation is understanding the relative influence of different sexually selected signals on those processes in both intra‐ and interspecific contexts. Different signals may be more or less susceptible to co‐option for species identification depending on the balance of sexual and ecological selection acting upon them. To examine this, we tested three predictions to explain geographic variation in long‐ versus short‐range sexual signals across a 3,500 + km transect of two related Australian field cricket species (Teleogryllus spp.): (a) selection for species recognition, (b) environmental adaptation and (c) stochastic divergence. We measured male calling song and male and female cuticular hydrocarbons (CHCs) in offspring derived from wild populations, reared under common garden conditions. Song clearly differentiated the species, and no hybrids were observed suggesting that hybridization is rare or absent. Spatial variation in song was not predicted by geography, genetics or climatic factors in either species. In contrast, CHC divergence was strongly associated with an environmental gradient supporting the idea that the climatic environment selects more directly upon these chemical signals. In light of recently advocated models of diversification via ecological selection on secondary sexual traits, the different environmental associations we found for song and CHCs suggest that the impact of ecological selection on population divergence, and how that influences speciation, might be different for acoustic versus chemical signals.Publisher PDFPeer reviewe
Method to determine defect positions below a metal surface by STM
The oscillatory voltage dependence of the conductance of a quantum point
contact in the presence of a single point-like defect has been analyzed
theoretically. Such signals are detectable and may be exploited to obtain
information on defect positions below a metal surface. Both tunnel junctions
and ballistic contacts of adiabatic shape have been considered. The effect of
quantum interference has been taking into account between the principal wave
that is directly transmitted through the contact and the partial wave that is
scattered by the contact and the defect. This effect leads to oscillations of
the conductance as a function of applied voltage. We obtain the dependence of
the period and amplitude of the conductance oscillations on the position of the
defect inside the metal.Comment: 16 pages, 7 figure
Signature of Fermi surface anisotropy in point contact conductance in the presence of defects
In a previous paper (Avotina et al.,Phys. Rev. B Vol.71, 115430 (2005)) we
have shown that in principle it is possible to image the defect positions below
a metal surface by means of a scanning tunnelling microscope. The principle
relies on the interference of electron waves scattered on the defects, which
give rise to small but measurable conductance fluctuations. Whereas in that
work the band structure was assumed to be free-electron like, here we
investigate the effects of Fermi surface anisotropy. We demonstrate that the
amplitude and period of the conductance oscillations are determined by the
local geometry of the Fermi surface. The signal results from those points for
which the electron velocity is directed along the vector connecting the point
contact to the defect. For a general Fermi surface geometry the position of the
maximum amplitude of the conductance oscillations is not found for the tip
directly above the defect. We have determined optimal conditions for
determination of defect positions in metals with closed and open Fermi
surfaces.Comment: 23 pages, 8 figure
Swift evaluation of electron density profiles obtained by the alkali beam emission spectroscopy technique using linearized reconstruction
Kondo Conductance in an Atomic Nanocontact from First Principles
The electrical conductance of atomic metal contacts represents a powerful
tool to detect nanomagnetism. Conductance reflects magnetism through anomalies
at zero bias -- generally with Fano lineshapes -- due to the Kondo screening of
the magnetic impurity bridging the contact. A full atomic-level understanding
of this nutshell many-body system is of the greatest importance, especially in
view of our increasing need to control nanocurrents by means of magnetism.
Disappointingly, zero bias conductance anomalies are not presently calculable
from atomistic scratch. In this Letter we demonstrate a working route
connecting approximately but quantitatively density functional theory (DFT) and
numerical renormalization group (NRG) approaches and leading to a
first-principles conductance calculation for a nanocontact, exemplified by a Ni
impurity in a Au nanowire. A Fano-like conductance lineshape is obtained
microscopically, and shown to be controlled by the impurity s-level position.
We also find a relationship between conductance anomaly and geometry, and
uncover the possibility of opposite antiferromagnetic and ferromagnetic Kondo
screening -- the latter exhibiting a totally different and unexplored zero bias
anomaly. The present matching method between DFT and NRG should permit the
quantitative understanding and exploration of this larger variety of Kondo
phenomena at more general magnetic nanocontacts.Comment: 11 pages, 3 figures. Supplementary materials under request at
[email protected]
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