766 research outputs found
Ad- and desorption of Rb atoms on a gold nanofilm measured by surface plasmon polaritons
Hybrid quantum systems made of cold atoms near nanostructured surfaces are
expected to open up new opportunities for the construction of quantum sensors
and for quantum information. For the design of such tailored quantum systems
the interaction of alkali atoms with dielectric and metallic surfaces is
crucial and required to be understood in detail. Here, we present real-time
measurements of the adsorption and desorption of Rubidium atoms on gold
nanofilms. Surface plasmon polaritons (SPP) are excited at the gold surface and
detected in a phase sensitive way. From the temporal change of the SPP phase
the Rubidium coverage of the gold film is deduced with a sensitivity of better
than 0.3 % of a monolayer. By comparing the experimental data with a Langmuir
type adsorption model we obtain the thermal desorption rate and the sticking
probability. In addition, also laser-induced desorption is observed and
quantified.Comment: 9 pages, 6 figure
Atomic Force Microscopy Study of Nano-Physiological Response of Ladybird Beetles to Photostimuli
Background: Insects are of interest not only as the most numerous and diverse group of animals but also as highly efficient bio-machines varying greatly in size. They are the main human competitors for crop, can transmit various diseases, etc. However, little study of insects with modern nanotechnology tools has been done. Methodology/Principal Findings: Here we applied an atomic force microscopy (AFM) method to study stimulation of ladybird beetles with light. This method allows for measuring of the internal physiological responses of insects by recording surface oscillations in different parts of the insect at sub-nanometer amplitude level and sub-millisecond time. Specifically, we studied the sensitivity of ladybird beetles to light of different wavelengths. We demonstrated previously unknown blindness of ladybird beetles to emerald color (,500nm) light, while being able to see UV-blue and green light. Furthermore, we showed how one could study the speed of the beetle adaptation to repetitive flashing light and its relaxation back to the initial stage. Conclusions: The results show the potential of the method in studying insects. We see this research as a part of what might be a new emerging area of ‘‘nanophysiology’ ’ of insects
Development of an atlas of palliative care in the Eastern Mediterranean Region through a stakeholder participative process
Background: The increasing number of people experiencing serious health-related suffering due to severe illness is an urgent issue in the WHO Eastern Mediterranean Region (EMR). Although palliative care can mitigate much of this suffering, its current development and indicators to measure progress remain unknown.
Aims: To describe the development of the Atlas of palliative care in the Eastern Mediterranean Region 2021.
Methods: Recently, the WHO Regional Office for the Eastern Mediterranean, together with a network of palliative care experts, identified the best indicators and collected data across the Region. These indicators include national palliative care strategies, number of specialized palliative care services per population, inclusion of palliative care in the health benefits package and national health budget, and the use of pain medication. These and other useful information form the Atlas of palliative care in the Eastern Mediterranean Region 2021.
Results: The Atlas shows that provision of specialized palliative care services and pain medication in the Region is low. Several of the indicators suitable to the region are new and include the level of public awareness of palliative care, inclusion of palliative care in health insurance plans, availability of centres of excellence for palliative clinical care, and availability of grants to finance palliative care research.
Conclusion: Adoption of favourable policies, educational initiatives, and the involvement of stakeholders, represent an opportunity for future development of palliative care in the EMR
Region-specific macroindicators on palliative care development in the Eastern Mediterranean region: a Delphi study
Background: The World Health Organization Office for the Eastern Mediterranean Region (WHO/EMRO), and the recently created palliative care experts network for the Eastern Mediterranean Region (EMR), decided to develop region-specific indicators for monitoring national palliative care development in the Region.
Aims: To identify relevant and feasible macro-indicators for palliative care development for the EMR.
Methods: Palliative care experts from the EMR were nominated and invited to complete a 2-round Delphi study to rate macro-indicators from previous studies and propose new ones based on the EMR regional characteristics. All indicators were assessed according to regional relevance (R) and feasibility (F). A content validity index (CVI) was calculated. Indicators with CVI ≥ 0.7/1, and scoring ≥ 7/9 for the R and F averages were selected.
Results: Twelve of the 22 countries in the Region were represented in the study. In the first round, 11 indicators were selected and 13 new ones proposed. In the second round, 15 indicators matched R, F and CVI criteria. Top-scored indicators were: existence of a current national palliative care strategy (R = 8, F = 8, CVI = 1); ratio of specialized services (for adults and children) in the country per population (R = 8, F = 7, CVI = 1); allocation of funds for palliative care in the national health budget by the Ministry of Health or equivalent government agency (R = 8, F = 6, CVI = 1); education for prequalification of doctors/nurses (R = 8, F = 8, CVI = 0.9); and availability of morphine and other strong opioids (R =8, F = 8, CVI= 0.9).
Conclusion: A baseline set of 15 region-specific indicators for measuring the development of palliative care were validated by experts in the EMR
Cavity QED with a Bose-Einstein condensate
Cavity quantum electrodynamics (cavity QED) describes the coherent
interaction between matter and an electromagnetic field confined within a
resonator structure, and is providing a useful platform for developing concepts
in quantum information processing. By using high-quality resonators, a strong
coupling regime can be reached experimentally in which atoms coherently
exchange a photon with a single light-field mode many times before dissipation
sets in. This has led to fundamental studies with both microwave and optical
resonators. To meet the challenges posed by quantum state engineering and
quantum information processing, recent experiments have focused on laser
cooling and trapping of atoms inside an optical cavity. However, the tremendous
degree of control over atomic gases achieved with Bose-Einstein condensation
has so far not been used for cavity QED. Here we achieve the strong coupling of
a Bose-Einstein condensate to the quantized field of an ultrahigh-finesse
optical cavity and present a measurement of its eigenenergy spectrum. This is a
conceptually new regime of cavity QED, in which all atoms occupy a single mode
of a matter-wave field and couple identically to the light field, sharing a
single excitation. This opens possibilities ranging from quantum communication
to a wealth of new phenomena that can be expected in the many-body physics of
quantum gases with cavity-mediated interactions.Comment: 6 pages, 4 figures; version accepted for publication in Nature;
updated Fig. 4; changed atom numbers due to new calibratio
The SCIDOTS Project: Evidence of benefits of an integrated tobacco cessation intervention in tuberculosis care on treatment outcomes
<p>Abstract</p> <p>Background</p> <p>There is substantial evidence to support the association between tuberculosis (TB) and tobacco smoking and that the smoking-related immunological abnormalities in TB are reversible within six weeks of cessation. Therefore, connecting TB and tobacco cessation interventions may produce significant benefits and positively impact TB treatment outcomes. However, no study has extensively documented the evidence of benefits of such integration. SCIDOTS Project is a study from the context of a developing nation aimed to determine this.</p> <p>Methods</p> <p>An integrated TB-tobacco intervention was provided by trained TB directly observed therapy short-course (DOTS) providers at five chest clinics in Malaysia. The study was a prospective non-randomized controlled intervention using quasi-experimental design. Using Transtheoretical Model approach, 120 eligible participants who were current smokers at the time of TB diagnosis were assigned to either of two treatment groups: conventional TB DOTS plus smoking cessation intervention (integrated intervention or SCIDOTS group) or conventional TB DOTS alone (comparison or DOTS group). At baseline, newly diagnosed TB patients considering quitting smoking within the next 30 days were placed in the integrated intervention group, while those who were contemplating quitting were assigned to the comparison group. Eleven sessions of individualized cognitive behavioral therapy with or without nicotine replacement therapy were provided to each participant in the integrated intervention group. The impacts of the novel approach on biochemically validated smoking cessation and TB treatment outcomes were measured periodically as appropriate.</p> <p>Results</p> <p>A linear effect on both 7-day point prevalence abstinence and continuous abstinence was observed over time in the intervention group. At the end of 6 months, patients who received the integrated intervention had significantly higher rate of success in quitting smoking when compared with those who received the conventional TB treatment alone (77.5% vs. 8.7%; p < 0.001). Furthermore, at the end of TB treatment (6 months or later), there were significantly higher rates of treatment default (15.2% vs. 2.5%; p = 0.019) and treatment failure (6.5% vs. 0%; p = 0.019) in the DOTS group than in the SCIDOTS group.</p> <p>Conclusion</p> <p>This study provides evidence that connecting TB-tobacco treatment strategy is significant among TB patients who are smokers. The findings suggest that the integrated approach may be beneficial and confer advantages on short-term outcomes and possibly on future lung health of TB patients who quit smoking. This study may have important implications on health policy and clinical practice related to TB management among tobacco users.</p
Probing quantum phases of ultracold atoms in optical lattices by transmission spectra in cavity QED
Studies of ultracold atoms in optical lattices link various disciplines,
providing a playground where fundamental quantum many-body concepts, formulated
in condensed-matter physics, can be tested in much better controllable atomic
systems, e.g., strongly correlated phases, quantum information processing.
Standard methods to measure quantum properties of Bose-Einstein condensates
(BECs) are based on matter-wave interference between atoms released from traps
which destroys the system. Here we propose a nondestructive method based on
optical measurements, and prove that atomic statistics can be mapped on
transmission spectra of a high-Q cavity. This can be extremely useful for
studying phase transitions between Mott insulator and superfluid states, since
various phases show qualitatively distinct light scattering. Joining the
paradigms of cavity quantum electrodynamics (QED) and ultracold gases will
enable conceptually new investigations of both light and matter at ultimate
quantum levels, which only recently became experimentally possible. Here we
predict effects accessible in such novel setups.Comment: 6 pages, 3 figure
Negative Effect of Smoking on the Performance of the QuantiFERON TB Gold in Tube Test.
False negative and indeterminate Interferon Gamma Release Assay (IGRA) results are a well documented problem. Cigarette smoking is known to increase the risk of tuberculosis (TB) and to impair Interferon-gamma (IFN-γ) responses to antigenic challenge, but the impact of smoking on IGRA performance is not known. The aim of this study was to evaluate the effect of smoking on IGRA performance in TB patients in a low and high TB prevalence setting respectively. Patients with confirmed TB from Denmark (DK, n = 34; 20 smokers) and Tanzania (TZ, n = 172; 23 smokers) were tested with the QuantiFERON-TB Gold In tube (QFT). Median IFN-γ level in smokers and non smokers were compared and smoking was analysed as a risk factor for false negative and indeterminate QFT results. Smokers from both DK and TZ had lower IFN-γ antigen responses (median 0.9 vs. 4.2 IU/ml, p = 0.04 and 0.4 vs. 1.6, p < 0.01), less positive (50 vs. 86%, p = 0.03 and 48 vs. 75%, p < 0.01) and more false negative (45 vs. 0%, p < 0.01 and 26 vs. 11%, p = 0.04) QFT results. In Tanzanian patients, logistic regression analysis adjusted for sex, age, HIV and alcohol consumption showed an association of smoking with false negative (OR 17.1, CI: 3.0-99.1, p < 0.01) and indeterminate QFT results (OR 5.1, CI: 1.2-21.3, p = 0.02). Cigarette smoking was associated with false negative and indeterminate IGRA results in both a high and a low TB endemic setting independent of HIV status
- …