1,100 research outputs found
Infrared imaging enhances retinal crystals in Bietti’s crystalline dystrophy
Infrared imaging dramatically increased the number of crystalline deposits visualized compared with clinical examination, standard color fundus photography, and red free imaging in patients with Bietti’s crystalline dystrophy. We believe that this imaging modality significantly improves the sensitivity with which these lesions are detected, facilitating earlier diagnosis and may potentially serve as a prognostic indicator when examined over time
InAs-AlSb quantum wells in tilted magnetic fields
InAs-AlSb quantum wells are investigated by transport experiments in magnetic
fields tilted with respect to the sample normal. Using the coincidence method
we find for magnetic fields up to 28 T that the spin splitting can be as large
as 5 times the Landau splitting. We find a value of the g-factor of about 13.
For small even-integer filling factors the corresponding minima in the
Shubnikov-de Haas oscillations cannot be tuned into maxima for arbitrary tilt
angles. This indicates the anti-crossing of neighboring Landau and spin levels.
Furthermore we find for particular tilt angles a crossover from even-integer
dominated Shubnikov-de Haas minima to odd-integer minima as a function of
magnetic field
Influence of Nitrogen and Phosphorus Fertilization on Fruiting and Yield Characteristics in Ratoon Crop of Banana (Musa spp. AAA) Cv. Grande Naine
In ratoon crop of banana cv. Grande Naine, date of shooting could be advanced by 35 days with application of 200g N in 5 splits + 60g P2O5 (86 days), compared to 300g N in 5 splits + 60g P2O5 (121 days). Subsequently, date of harvest also got advanced by 53 days, and fruits were harvested on 9th December in the same treatment. Higher dose of N fertilization delayed shooting and harvesting period, taking 121 days for shooting and 145 days from shooting to harvest in the treatment 300g N (5 split doses) + 90g P2O5. Various N and P treatments affected bunch weight and number of hands per bunch significantly. Although N and P combination-treatments had no significant effect on bunch weight or number of hands per bunch, application of 200g N in 5 splits and 60g P2O5 per plant gave maximum bunch weight (18.11kg) and number of hands per bunch (10.61). Minimum bunch weight (15.37kg) and the least number of hands per bunch (7.08) were obtained with 150g N in 5 splits + 90g P2O5. Hand-weight (2.20kg), number of fingers per hand (19.75), and finger length (20.30cm) was highest with application of 200g N in 5 splits + 60g P2O5 per plant. Least hand-weight (1.64kg), number of fingers per hand (15.77), and finger-length (17.92cm) was recorded with 150g N in 5 splits + 90g P2O5. Bunch weight, number of hands per bunch, hand-weight and number of fingers per hand too was affected significantly with sole application of nitrogen or phosphorus
Effect of Spacing on Canopy Microclimate, Vegetative Growth and Yield Attributes in Guava (Psidium guajava L.)
The present investigation was conducted to examine the effect of spacing on variation in canopy microclimate, vegetative growth and yield attributes in guava (cv. Allahabad Safeda). Oservations revealed that with wide plant spacing (from 6x2m to 6x4m), interception of solar radiation increased significantly. Similarly, with increase in spacing between plants, mean canopy temperature was need to increase while relative humidity decreased. Plant growth in terms of stock and scion girth, tree spread (N-S) and canopy volume increased with wide plant spacing, while tree height decreased with increase in plant spacing. Number of fruits per plant, yield per plant and fruiting density was higher at 6x5m and least in 6x2m spacing. Wider plant spacing was found to be better owing to maximum absorption of solar radiation and optimum microclimate in the orchard leading to better yield in plants, higher fruiting density and yield efficiency. However, yield/ha was maximum in 6x2m spacing during rainy season and in 6x3m spacing during winter
Prevalence and factors predictive of intraocular fungal infection in patients with fungemia at an academic urban tertiary care center
Objective To report the prevalence and to identify factors predictive of intraocular infection in patients with fungemia receiving prophylactic antifungal therapy. Methods A retrospective review of patients who received prophylactic antifungal therapy and a dilated fundus examination at an academic urban tertiary care center from 2000 to 2007. Basic demographic information, fungal species grown, antifungal agent(s) used, number of positive blood culture specimens, visual acuity, visual symptoms, and known risks of disseminated candidiasis were noted. Logistic regression analysis was used to determine the factors significantly associated with intraocular fungal infection. Results A total of 132 patients with positive fungemia culture were requested to have ophthalmology consults. The prevalence of ocular infection was 6.9% (N=9). All nine patients were infected with Candida species. Undergoing gastrointestinal (GI) surgery within the prior 6 months was significantly related to developing intraocular infection, with an odds ratio of 18.5 (95% confidence interval, 15.1–24.3; P=0.002). Having ≥3 positive fungal blood cultures was also a significant risk factor, with an odds ratio of 2.6 (95% confidence interval, 1.8–3.7; P=0.03). Among 40 patients having GI surgery, eight (20.0%) had intraocular fungal disease, compared with one of 92 patients (1.1%) not having GI surgery. Among 125 patients with a negative baseline examination result, two of 32 patients (6.3%), who had recent GI surgery, subsequently developed fungal ocular disease, compared with 0 of 93 patients (0%), who did not have recent GI surgery. Conclusion Recent GI surgery and higher numbers of positive fungal blood culture specimens may be predictive ofcandida ocular infections. Normal baseline fundoscopy examination results in patients with such risks may require repeat evaluations to detect delayed manifestations
Assessment of strategies for switching patients from olanzapine to risperidone: A randomized, open-label, rater-blinded study
<p>Abstract</p> <p>Background</p> <p>In clinical practice, physicians often need to change the antipsychotic medications they give to patients because of an inadequate response or the presence of unacceptable or unsafe side effects. However, there is a lack of consensus in the field as to the optimal switching strategy for antipsychotics, especially with regards to the speed at which the dose of the previous antipsychotic should be reduced. This paper assesses the short-term results of strategies for the discontinuation of olanzapine when initiating risperidone.</p> <p>Methods</p> <p>In a 6-week, randomized, open-label, rater-blinded study, patients with schizophrenia or schizoaffective disorder, on a stable drug dose for more than 30 days at entry, who were intolerant of or exhibiting a suboptimal symptom response to more than 30 days of olanzapine treatment, were randomly assigned to the following switch strategies (common risperidone initiation scheme; varying olanzapine discontinuation): (i) abrupt strategy, where olanzapine was discontinued at risperidone initiation; (ii) gradual 1 strategy, where olanzapine was given at 50% entry dose for 1 week after risperidone initiation and then discontinued; or (iii) gradual 2 strategy, where olanzapine was given at 100% entry dose for 1 week, then at 50% in the second week, and then discontinued.</p> <p>Results</p> <p>The study enrolled 123 patients on stable doses of olanzapine. Their mean age was 40.3 years and mean (± standard deviation (SD)) baseline Positive and Negative Syndrome Scale (PANSS) total score of 75.6 ± 11.5. All-cause treatment discontinuation was lowest (12%) in the group with the slowest olanzapine dose reduction (gradual 2) and occurred at half the discontinuation rate in the other two groups (25% in abrupt and 28% in gradual 1). The relative risk of early discontinuation was 0.77 (confidence interval 0.61–0.99) for the slowest dose reduction compared with the other two strategies. After the medication was changed, improvements at endpoint were seen in PANSS total score (-7.3; <it>p </it>< 0.0001) and in PANSS positive (-3.0; <it>p </it>< 0.0001), negative (-0.9; <it>p </it>= 0.171) and anxiety/depression (-1.4; <it>p </it>= 0.0005) subscale scores. Severity of movement disorders and weight changes were minimal.</p> <p>Conclusion</p> <p>When switching patients from olanzapine to risperidone, a gradual reduction in the dose of olanzapine over 2 weeks was associated with higher rates of retention compared with abrupt or less gradual discontinuation. Switching via any strategy was associated with significant improvements in positive and anxiety symptoms and was generally well tolerated.</p> <p>Trial registration</p> <p>ClinicalTrials.gov NCT00378183</p
Zero-field spin splitting in InAs-AlSb quantum wells revisited
We present magnetotransport experiments on high-quality InAs-AlSb quantum
wells that show a perfectly clean single-period Shubnikov-de Haas oscillation
down to very low magnetic fields. In contrast to theoretical expectations based
on an asymmetry induced zero-field spin splitting, no beating effect is
observed. The carrier density has been changed by the persistent photo
conductivity effect as well as via the application of hydrostatic pressure in
order to influence the electric field at the interface of the electron gas.
Still no indication of spin splitting at zero magnetic field was observed in
spite of highly resolved Shubnikov- de Haas oscillations up to filling factors
of 200. This surprising and unexpected result is discussed in view of other
recently published data.Comment: 4 pages, 3 figures, submitted to Phys. Rev.
Local density of states and scanning tunneling currents in graphene
We present exact analytical calculations of scanning tunneling currents in
locally disordered graphene using a multimode description of the microscope
tip. Analytical expressions for the local density of states (LDOS) are given
for energies beyond the Dirac cone approximation. We show that the LDOS at the
and sublattices of graphene are out of phase by implying that the
averaged LDOS, as one moves away from the impurity, shows no trace of the
(with the Fermi momentum) Friedel modulation. This means that a
STM experiment lacking atomic resolution at the sublattice level will not be
able of detecting the presence of the Friedel oscillations [this seems to be
the case in the experiments reported in Phys. Rev. Lett. {\bf 101}, 206802
(2008)]. The momentum maps of the LDOS for different types of impurities are
given. In the case of the vacancy, features are seen in these maps. In
all momentum space maps, and features are seen. The
features are different from what is seen around zero momentum. An
interpretation for these features is given. The calculations reported here are
valid for chemical substitution impurities, such as boron and nitrogen atoms,
as well as for vacancies. It is shown that the density of states close to the
impurity is very sensitive to type of disorder: diagonal, non-diagonal, or
vacancies. In the case of weakly coupled (to the carbon atoms) impurities, the
local density of states presents strong resonances at finite energies, which
leads to steps in the scanning tunneling currents and to suppression of the
Fano factor.Comment: 21 pages. Figures 6 and 7 are correctly displayed in this new versio
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