Low-temperature solution-processed flexible solar cells based on (In,Ga)N nanocubes

Indium gallium nitride nanocubes were syntheized via a low-temperature chemical route. Energy-dispersive X-ray spectroscopy and X-ray diffraction analyses confirmed the successful fabrication of (In,Ga)N with various indium mole fractions. The bandgap of the material was tunded as a function of the indium content. The fabricated nanocubes showed a deep level photoluminescence emission at 734 nm as well as in the visible region at 435-520 nm. The Hall effect measurements showed the hole concentration to constantly increase from 6.2 × 10(16) to 2.3 × 10(18) cm(-3), while the hole mobility to decrease from 0.92 to 0.1 cm(2) /(V s) as the doping ratio increases from 0.005 to 0.025 cm(-3). The solar cell device made of nanocubes film containing 0.4 indium on flexible substrates showed a short-circuit current density of 12.47 mA/cm(2) and an open-circuit voltage (Voc) of 0.48 V with 54% fill factor. The relationship between Voc and indium content in the fabricated films was also investigated.

Intra-aortic balloon pump (IABP) counterpulsation improves cerebral perfusion in patients with decreased left ventricular function

Background:

The current goal of treatment after acute ischemic stroke is the increase of cerebral blood flow (CBF) in ischemic brain tissue. Intra-aortic balloon pump (IABP) counterpulsation in the setting of cardiogenic shock is able to reduce left ventricular afterload and increase coronary blood flow. The effects of an IABP on CBF have not been sufficiently examined. We hypothesize that the use of an IABP especially enhances cerebral blood flow in patients with pre-existing heart failure.

Methods:

In this pilot study, 36 subjects were examined to investigate the effect of an IABP on middle cerebral artery (MCA) transcranial Doppler (TCD) flow velocity change and relative CBF augmentation by determining velocity time integral changes (ΔVTI) in a constant caliber of the MCA compared to a baseline measurement without an IABP. Subjects were divided into two groups according to their left ventricular ejection fraction (LVEF): Group 1 LVEF >30% and Group 2 LVEF ≤30%.

Results:

Both groups showed an increase in CBF using an IABP. Patients with a LVEF ≤30% showed a significantly higher increase of ΔVTI in the MCA under IABP augmentation compared to patients with a LVEF >30% (20.9% ± 3.9% Group 2 vs.10.5% ± 2.2% Group 1, p<0,05). The mean arterial pressure (MAP) increased only marginally in both groups under IABP augmentation.

Conclusions:

IABP improves cerebral blood flow, particularly in patients with pre-existing heart failure and highly impaired LVEF. Hence, an IABP might be a treatment option to improve cerebral perfusion in selected patients with cerebral misperfusion and simultaneously existing severe heart failure.

Midbrain dopamine function in schizophrenia and depression: a post-mortem and positron emission tomographic imaging study

Elevated in vivo markers of presynaptic striatal dopamine activity have been a consistent finding in schizophrenia, and include a large effect size elevation in dopamine synthesis capacity. However, it is not known if the dopaminergic dysfunction is limited to the striatal terminals of dopamine neurons, or is also evident in the dopamine neuron cell bodies, which mostly originate in the substantia nigra. The aim of our studies was therefore to determine whether dopamine synthesis capacity is altered in the substantia nigra of people with schizophrenia, and how this relates to symptoms. In a post-mortem study, a semi-quantitative analysis of tyrosine hydroxylase staining was conducted in nigral dopaminergic cells from post-mortem tissue from patients with schizophrenia (n = 12), major depressive disorder (n = 13) and matched control subjects (n = 13). In an in vivo imaging study, nigral and striatal dopaminergic function was measured in patients with schizophrenia (n = 29) and matched healthy control subjects (n = 29) using (18)F-dihydroxyphenyl-L-alanine ((18)F-DOPA) positron emission tomography. In the post-mortem study we found that tyrosine hydroxylase staining was significantly increased in nigral dopaminergic neurons in schizophrenia compared with both control subjects (P < 0.001) and major depressive disorder (P < 0.001). There was no significant difference in tyrosine hydroxylase staining between control subjects and patients with major depressive disorder, indicating that the elevation in schizophrenia is not a non-specific indicator of psychiatric illness. In the in vivo imaging study we found that (18)F-dihydroxyphenyl-L-alanine uptake was elevated in both the substantia nigra and in the striatum of patients with schizophrenia (effect sizes = 0.85, P = 0.003 and 1.14, P < 0.0001, respectively) and, in the voxel-based analysis, was elevated in the right nigra (P < 0.05 corrected for family wise-error). Furthermore, nigral (18)F-dihydroxyphenyl-L-alanine uptake was positively related with the severity of symptoms (r = 0.39, P = 0.035) in patients. However, whereas nigral and striatal (18)F-dihydroxyphenyl-L-alanine uptake were positively related in control subjects (r = 0.63, P < 0.001), this was not the case in patients (r = 0.30, P = 0.11). These findings indicate that elevated dopamine synthesis capacity is seen in the nigral origin of dopamine neurons as well as their striatal terminals in schizophrenia, and is linked to symptom severity in patients.

Dopaminergic function in the psychosis spectrum: an [18F]-DOPA imaging study in healthy individuals with auditory hallucinations

BACKGROUND

The psychosis phenotype appears to exist in the population as a continuum, but it is not clear if subclinical psychotic symptoms and psychotic disorders share the same neurobiology. We investigated whether the dopaminergic dysfunction seen in psychotic disorders is also present in healthy, well-functioning people with hallucinations.

METHODS

We compared dopamine synthesis capacity (using 6-[(18)F]fluoro-L-DOPA [[(18)F]-DOPA] positron emission tomography imaging) in 16 healthy individuals with frequent persistent auditory verbal hallucinations (hallucinating group) with that in 16 matched controls.

RESULTS

There was no significant difference in dopamine synthesis capacity in the striatum, or its functional subdivisions, between groups and no relationship between subclinical psychotic symptom severity or schizotypal traits and dopamine synthesis capacity in the hallucinating group.

CONCLUSIONS

Altered dopamine synthesis capacity is unlikely to underlie subclinical hallucinations, suggesting that although there may be a phenomenological psychosis continuum, there are distinctions at the neurobiological level.

Potential antileishmanial effect of three medicinal plants

The antileishmanial activity of three organic solvent extracts and water residue of the plants: Acacia nilotica (Mimosaceae) (husk), Ambrosia miratima (Astraceae) (aerial shoot) and Azadarichta indica (Meliaceae) (leaves) were tested in vitro against Leishmania donovani promastigotes. The study revealed that the extracts of A. nilotica and A. miratima have effectious antileishmanial activity at concentrations (IC₅₀) less than 8 μg/ml, while the extracts of A. indica lack antileishmanial activity. The chromatographic analysis of the ethyl acetate extract of A. nilotica, the most potent extract, resulted in four TLC fractions. Three of these fractions possessed antileishmanial activity. Phytochemical study of the potent fractions revealed the presence of poly hydroxyl compounds.

The beliefs and knowledge of patients newly diagnosed with cancer in a UK ethnically diverse population

AIMS

To compare knowledge about the outcome of cancer treatment and beliefs about the causes of cancer among British South Asian (BSA) cancer patients of predominantly Gujarati origin with the beliefs held by British White (BW) cancer patients. We also wanted to determine if these beliefs impacted upon the patients' mental health.

MATERIALS AND METHODS

We administered a questionnaire about cancer beliefs to 94 BSA and 185 BW newly diagnosed cancer patients at the Leicestershire Cancer Centre. Using a Likert seven-item scale, we analysed patients' views on confidentiality, outcome and cancer treatment and 15 items about beliefs about the causes of cancer. Patients also completed the Hospital Anxiety and Depression Scale, Patient Health Questionnaire, Mini-MAC, Distress Thermometer and newly developed Cancer Insight and Denial, and Physician/Patient Trust questionnaires.

RESULTS

Most (232/279; 83.2%) believed cancer was curable. However, significantly more BSA (10.6% versus 2.7% BW P=0.001) believed cancer was incurable. Although most (86.4%) agreed that smoking can cause cancer, there was a widespread lack of knowledge of the importance of diet and obesity as contributing causes of cancer. There was, in general, an over-emphasis on pollution, stress and injury as important aetiological agents. There was a strong belief in supernatural involvement in the development of cancer among a minority of BSA patients. Twenty per cent of this sample believed that treatment, especially surgery, caused the cancer to spread and this was associated with significant depression in BSAs (P=0.019) and anxiety in both BW (P=0.006) and BSA (P=0.0134) patients.

CONCLUSION

Our results show that there is a continual need for education about the causes of cancer both in BW and BSA patients.

Measles Outbreak in Qatar 2007

To analyze the epidemiological and clinical characteristic of a measles outbreak in Qatar in 2007, the records of 21 2 confirmed cases of measles were analyzed retrospectively, confirmation being based on clinical suspicion of the disease with a positive measles IgM (170 cases) and /or exposure to a laboratory confirmed measles case during the infectious period (42 cases; epidemiologic link). Eighty five percent of the cases occurred between April and July. Seventeen percent were in infants <  1 year of age, 47% in children between 1-5 years of age, 24% in school age children < 10 year of age and 1 2% in children >10 years old. Vaccinations were up to date in 60% of cases, second dose missed in 30% and no vaccination in 10% because of travel outside the country, concurrent illness, or lack of transportation. Thirty one percent of the cases required admission, with a mean hospital stay of four days. Cases were reported predominantly in Pakistani and Qatari patients, living mainly in three areas within the capital, Abu Hammour, Al Rayyan, and Al Mamuora.

Conclusion: Status of vaccination in Qatar needs careful analysis and the vaccination schedule should be reviewed. Early administration of vaccine, increasing community awareness, a well-coordinated school-based immunization program and immunization campaigns are required to prevent future outbreaks.

Development of an algorithm of satellite markers for monitoring chimerism status in post-allogeneic haematopoietic stem cell transplantation patients

INTRODUCTION

Analysis of variable number tandem repeats (VNTRs) by polymerase chain reaction (PCR) is a common method used to predict engraftment status in post-allogeneic haematopoeitic stem cell transplantation (HSCT) patients. Different populations have different copies of repeated DNA sequence and hence, different percentage of informativeness between patient and donor.

METHODS

PCR amplification of four highly polymorphic VNTR markers (YNZ-22, D1S80, D1S111 and ApoB) was conducted on 60 patient-donor pairs. The informativeness of the markers was analysed using 3% agarose gel electrophoresis.

RESULTS

We developed an algorithm for identification of informative VNTR markers in 60 post-allogeneic HSCT patients. YNZ-22 was the most informative (72%), followed by D1S80 (63%) and D1S111 (60%), while the least informative was ApoB (47%). The degree of informativeness achieved was 95%, which could discriminate 57 patient-donor pairs, when all four markers were combined.

CONCLUSION

Since population genetic studies on VNTR loci are not well established in Southeast Asia, the present study is useful to determine reliable markers during the initial screening step of chimerism analysis. By following this algorithm, we are able to reduce time and cost of finding a suitable VNTR marker in our cohort.