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Silicon nanocrystals, average sizes ranging between 3 and 7 nm, were formed in sapphire matrix by ion implantation and subsequent annealing. Evolution of the nanocrystals was detected by Raman spectroscopy and x-ray diffraction (XRD). Raman spectra display that clusters in the matrix start to form nanocrystalline structures at annealing temperatures as low as 800 °C in samples with high dose Si implantation. The onset temperature of crystallization increases with decreasing dose. Raman spectroscopy and XRD reveal gradual transformation of Si clusters into crystalline form. Visible photoluminescence band appears following implantation and its intensity increases with subsequent annealing process. While the center of the peak does not shift, the intensity of the peak decreases with increasing dose. The origin of the observed photoluminescence is discussed in terms of radiation induced defects in the sapphire matrix. [ABSTRACT FROM AUTHOR]

There are limited data showing right ventricular preload increase due to high-flow arteriovenous fistulas (AVFs). This cross-sectional study investigated whether high AVF flow had an impact on right ventricular function in patients undergoing hemodialysis. Sixty-four patients aged between 18 and 85 years who were on routine hemodialysis with >2 hemodialysis sessions per week for at least 3 months via an AVF were studied. Patients with inadequate flow fistulas, severe chronic obstructive pulmonary disease, history of pulmonary embolism, primary pulmonary hypertension, severe mitral, aortic or pulmonary regurgitation, and/or stenosis were excluded. After an initial evaluation, 44 patients (mean age: 58.50 ± 16.84, male:female = 23:21) were considered eligible. Right ventricular function was assessed by tricuspid annular plane systolic excursion (TAPSE). AVF blood flow was measured with duplex ultrasound. There were 15 patients (34.1%) with a TAPSE of <16 mm. AVF blood flow was significantly higher in patients with impaired versus normal right ventricular function (1631.53 ± 738.17 vs. 1060.55 ± 539.92 min/ml, respectively, P = 0.003). Low left ventricular ejection fraction (odds ratio [OR]: 1.15, 95% confidence intervals [CI]: 1.007-1.334, P = 0.04), high interventricular septum thickness (OR: 1.64, 95% CI: 1.104-2.464, P = 0.01), and high AVF blood flow (OR: 1.00, 95% CI: 1.000-1.003, P = 0.03) were independent predictors of impaired right ventricular function. In addition to known risk factors that predominantly increase right ventricular afterload, excessive AVF blood flow was found to be independently associated with impaired right ventricular function, possibly by increasing right ventricular preload. [ABSTRACT FROM AUTHOR]

In a previous meta-analysis across almost 200 neuroimaging experiments, working memory for object location showed significantly stronger convergence on the posterior superior frontal gyrus, whereas working memory for identity showed stronger convergence on the posterior inferior frontal gyrus (dorsal to, but overlapping with Brodmann's area BA 44). As similar locations have been discussed as part of a dorsal frontal-superior parietal reach system and an inferior frontal grasp system, the aim of the present study was to test whether the regions of working-memory related 'what' and 'where' processing show a similar distinction in parietal connectivity. The regions that were found in the previous meta-analysis were used as seeds for functional connectivity analyses using task-based meta-analytic connectivity modelling and task-independent resting state correlations. While the ventral seed showed significantly stronger connectivity with the bilateral intraparietal sulcus (IPS), the dorsal seed showed stronger connectivity with the bilateral posterior inferior parietal and the medial superior parietal lobule. The observed connections of regions involved in memory for object location and identity thus clearly demonstrate a distinction into separate pathways that resemble the parietal connectivity patterns of the dorsal and ventral premotor cortex in non-human primates and humans. It may hence be speculated that memory for a particular location and reaching towards it as well as object memory and finger positioning for manipulation may rely on shared neural systems. Moreover, the ensuing regions, in turn, featured differential connectivity with the bilateral ventral and dorsal extrastriate cortex, suggesting largely segregated bilateral connectivity pathways from the dorsal visual cortex via the superior and inferior parietal lobules to the dorsal posterior frontal cortex and from the ventral visual cortex via the IPS to the ventral posterior frontal cortex that may underlie action and cognition. [ABSTRACT FROM AUTHOR]

Systemic lupus erythematosus (SLE) patients are at increased risk of thrombosis and cardiovascular diseases. Aspirin is an effective treatment option for these patients. The aim of this study was to investigate the presence of aspirin resistance in SLE patients. We studied aspirin resistance in 33 SLE patients and nine healthy controls by using a Multiplate® impedance aggregometer (Dynabyte GmbH, Munich, Germany). Twenty-six SLE patients were on regular aspirin treatment. Aspirin resistance was found in five (19.2%) out of 26 patients who were on aspirin treatment. When the tests were repeated by adding acetylsalicylic acid in the medium, all of these patients became responsive to the aspirin. SLE disease activity, body mass index, smoking status, and the presence of anticardiolipin antibodies or positive lupus anticoagulant test results were no different in patients with or without aspirin resistance. (p > 0.05 for all). Our results suggest that there may be a considerable number of SLE patients with aspirin resistance. [ABSTRACT FROM PUBLISHER]

An aseptic abscess (AA) is an auto-inflammatory disorder characterized by necrotic lymph nodes and internal organ abscesses, most frequently located in the spleen. Described herein are two cases of aseptic abscesses; one in a patient with Behçet's disease and the other in a patient with mesenteric panniculitis. [ABSTRACT FROM AUTHOR]

G. Kantarci, Z. Eren, A. Demirağ, I. Dogan, F. Çakalagaoglu, G. Yilmaz. JC virus-associated nephropathy in a renal transplant recipient and comparative analysis of previous cases. Transpl Infect Dis 2011: 89-92. All rights reserved We report JC virus (JCV)-associated nephropathy in a renal allograft recipient and summarize the clinical and laboratory data of the 8 previous cases. A 28-year-old male renal allograft recipient received a preemptive transplant from his father. Six months later, a kidney biopsy was performed because of deterioration of allograft function. Biopsy revealed tubulointerstitial mononuclear infiltrates with normal glomeruli; on hematoxylin and eosin staining, basophilic nuclear inclusions were seen in the nucleus of tubular cells. Urinary cytology failed to demonstrate decoy cells, but polymerase chain reaction of a urinary sample was positive for JCV 3.15 × 10 copies/mL. Additionally, polyomavirus (SV40) immunohistochemical staining was performed and was positive in the enlarged nuclei of tubular epithelial cells in the kidney biopsy sample. After the diagnosis of polyomavirus-associated nephropathy (PVAN) was confirmed by kidney biopsy, immunosuppressive agents were reduced. Intravenous immunoglobulin was administered 5 times at a dose of 500 mg/kg every other 3 weeks. Two months after diagnosis, the serum creatinine became stable and urinary viral load of JCV was decreased. Because viruria was still present, tacrolimus was converted to sirolimus. Four months after immunosuppressive agent conversion from tacrolimus to sirolimus, the viruria had disappeared. Review of the literature and our case demonstrates that male gender, previous acute rejection episode, low incidence of JCV viremia, PVAN pattern B histology, and reducing immunosuppression are the diagnostic touchstones for PVAN due to JCV. [ABSTRACT FROM AUTHOR]

Background: Biases in adverse effect reporting in randomized controlled trials (RCTs) [e.g. due to investigator expectations or assessment quality] can be quantified by studying the rates of adverse events reported in the placebo arms of such trials.Objective: We compared the rates of adverse effects reported in the placebo arms of tricyclic antidepressant (TCA) trials and placebo arms of selective serotonin reuptake inhibitor (SSRI) trials.Methods: We conducted a literature search for RCTs across PUBMED, Scopus and the Cochrane Central Register of Controlled Trials (CENTRAL). Only studies allowing adverse effect analysis were included. Publication year ranged from 1981 to 2007.Results: Our systematic review and meta-analysis included 143 placebocontrolled RCTs and data from 12,742 patients. Only 21% of studies used structured and systematic adverse effect ascertainment strategies. The way in which trials recorded adverse events influenced the rate of adverse effects substantially. Systematic assessment led to higher rates than less systematic assessment. Far more adverse effects were reported in TCA-placebo groups compared with SSRI-placebo groups, e.g. dry mouth (odds ratio [OR] = 3.5; 95% CI 2.9, 4.2); drowsiness (OR = 2.7; 95%CI 2.2, 3.4); constipation (OR= 2.7; 95%CI 2.1, 3.6); sexual problems (OR =2.3; 95%CI 1.5, 3.5). Regression analyses controlling for various influencing factors confirmed the results.Conclusion: Adverse effect profiles reported in clinical trials are strongly influenced by expectations from investigators and patients. This difference cannot be attributed to ascertainment methods. Adverse effect patterns of the drug group are closely related to adverse effects of the placebo group. These results question the validity of the assumption that adverse effects in placebo groups reflect the 'drug-unspecific effects'. [ABSTRACT FROM AUTHOR]

Rapid globalization in recent decades and the consequent demands make it essential for supply chains (SCs) and their managers to account for real-world dynamics in managing businesses to successfully compete and emerge as market leaders. The vast majority of SC models discussed in the literature are "static": greatly stylized, generally local and decision specific. While they present a number of important insights into the working of SCs, they are constricted by the model-related assumptions and replication-related problems. The dynamic nature of the business environment is subjecting SC players to a much more volatile market environment than ever before. Agent-based solutions are particularly relevant in this changing market context. Agent-based approach for supply chain management (SCM) was given a boost with the unveiling of the "TAC-SCM" competition in 2003 by Carnegie Mellon University and the Swedish Institute of Computer Science through the Trading Agent Competition (TAC). Based on our competition experience for 2 years, we advocate in this paper the importance of incorporating real-world marketplace dynamics into SC modelling through agent-based solutions. We present innovative strategies adopted by some of the successful teams in the competition and detail important aspects of our own agent. [ABSTRACT FROM AUTHOR]

Reflex sympathetic dystrophy (RSD) is characterized by severe pain, swelling, autonomic dysfunction and usually affects extremities following trauma. In this case we report a 16-year-old female patient who had undergone several operations on the distal of the right lower extremity over a period of 1.5 years. During the follow-up she was determined to have adolescent osteomalacia (primary vitamin D deficiency) and RSD findings at the right lower extremity. We also examined reports in the literature concerning the probable initiator role of vitamin D deficiency among the mechanisms of RSD occurrence. This is the first report of primary vitamin D deficiency accompanied by RSD in an adolescent with multiple fractures. [ABSTRACT FROM AUTHOR]

Relaxation and opening of the oesophago-gastric junction (OGJ) is crucial for oesophageal transport. A novel ultrasound technique was used to determine OGJ opening, before and after atropine, in 12 normals. An ultrasound probe, a solid-state pressure transducer and an infusion tube were placed inside a 20-mm diameter bag, which was placed across the OGJ. At various bag pressures ultrasound transducer was pulled across the bag. Acquired B-mode ultrasound images were converted into M-mode image to display the oesophagus, OGJ and stomach. At low bag-pressure (<20 mmHg), the OGJ but not oesophagus and stomach, is collapsed around the bag. Increasing bag pressure results in gradual opening of the OGJ from distal end. M-mode image identified the narrowest region of OGJ and corresponding cross-sectional area (CSA) was measured. Mean bag pressure to initial OGJ opening was 18 mmHg. Linear relationship between bag-pressure and OGJ-CSA was observed. Atropine reduced opening bag pressure and shifted the OGJ pressure-CSA curve upward without altering slope, i.e. compliance. Our novel ultrasound technique to study the OGJ opening function shows two distinct components; firstly, related to the tonic OGJ contraction and secondly, to passive or viscoelastic properties of the OGJ. [ABSTRACT FROM AUTHOR]

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