Evaluating the technical impacts associated with connecting distributed generation to distribution networks is a complex activity requiring a wide range of network operational and security effects to ...be qualified and quantified. One means of dealing with such complexity is through the use of indices that indicate the benefit or otherwise of connections at a given location and which could be used to shape the nature of the contract between the utility and distributed generator. This paper presents a multiobjective performance index for distribution networks with distributed generation which considers a wide range of technical issues. Distributed generation is extensively located and sized within the IEEE-34 test feeder, wherein the multiobjective performance index is computed for each configuration. The results are presented and discussed.
The introduction of radiological contrast media and intravenous (i.v.) urography in clinical diagnostics in the 1930s enabled the discovery of several diseases, including the medullary sponge kidney ...(MSK). MSK is a renal malformation characterized by cystic anomalies of precalyceal ducts, which is frequently associated with nephrocalcinosis and renal stones. Although it was first recognized by G Lenarduzzi in 1939, its thorough description was the result of the ante litteram multidisciplinary cooperation between a radiologist (Lenarduzzi), a urologist (Cacchi), and a pathologist (Ricci), all at the Padua University Hospital. These authors ‘established’ the paradigm for its diagnosis that is still used today. I.v. urography is the gold standard for the diagnosis of MSK, but as the technique is used less and less, there is a concrete possibility of this renal condition being forgotten in the future. Although the pathogenesis of MSK has yet to be elucidated, its association with different malformative conditions supports the idea that it is a developmental disorder. Recent findings suggest that MSK may be the consequence of a disruption of the ureteral-bud/metanephric-blastema interface.
The objectives of this study were to investigate the usefulness of adrenal vein sampling in identifying the etiology of primary aldosteronism (PA) in patients with equivocal CT and MR findings. ...Between 1990 and 1999, 104 referred hypertensive patients (45 women and 59 men, aged 49.6 +/- 11.6 yr) were diagnosed to have PA with inconclusive computed tomography scan and magnetic resonance results, based on established criteria. Adrenal vein sampling (AVS) for measurement of plasma aldosterone (A) and cortisol (C) levels was performed in all. Selectivity of AVS was assessed by the ratio between C levels in each adrenal vein and in the infrarenal inferior vena cava plasma (C(side)/C(IVC)). A receiver operator characteristics analysis was carried out to establish 1) the best AVS-derived index, 2) the degree of selectivity that could provide an accurate diagnosis, and 3) whether a correct diagnosis could be made from a unilaterally selective AVS. An aldosterone-producing adenoma (average diameter, 12.2 +/- 0.08 mm) was eventually diagnosed in 41 patients (39.4%) and was excluded in the rest. Adrenal vein rupture leading to partial adrenal loss occurred in 1 patient (0.9% complication rate). By assuming a cut-off value of C(side)/C(IVC) > or = 1.1, AVS was selective in 85.7% and 94.1% of cases on the right and left sides, respectively, and bilaterally in 80.6% of cases. Of all AVS-derived indexes, the A/C of one over the A/C contralateral side (A/C)(side)/(A/C)(contralateral side) furnished the best diagnostic accuracy. With a bilaterally selective AVS, a value of (A/C)(side)/(A/C)(contralateral side) > or = 2 provided a conclusive etiological diagnosis of PA in 79.7% of cases. At variance, no accurate diagnosis could be made from unilaterally selective AVS. AVS was feasible and safe in most PA patients with inconclusive computed tomography and magnetic resonance scans. When bilaterally selective (i.e. C(side)/C(IVC) > or = 1.1) a ratio of (A/C)(side)/(A/C)(control) > or = 2 provided the best compromise of sensitivity and false positive rate for lateralization of the etiology of PA.
Purpose
The continuous discovery of new subtypes of neuromuscular disorders demands more accurate imaging analyses. We set out to establish the specific patterns of muscular involution using magnetic ...resonance imaging (MRI).
Materials and methods
A systematic clinical evaluation based on the Medical Research Council scale and MRI was completed in ten patients with calpainopathy limb-girdle muscular dystrophy (LGMD)-2A, 16 with dysferlinopathy (LGMD-2B), ten with hyaline body myopathy (HBM), six with myotonic dystrophy (MD) types 1 and 5 with MD type 2. Severity of fibroadipose degeneration was specifically staged using T1-weighted sequences. Turbo inversion recovery magnitude (TIRM) sequences were used to assess oedema-like changes.
Results
T1 scans showed recurrent patterns of fibroadipose replacement, whereas TIRM images revealed differences in oedema-like changes between the various diseases. In LGMD, the posterior compartments are more vulnerable to degeneration. In HBM, fatty muscle degeneration and oedema are allocated to muscles of the posterior compartments of the leg. In MD, fatty muscle degeneration and oedematous changes are allocated to muscles of the anterior thigh and posterior lower leg.
Conclusions
Imaging examination suggests a characteristic pattern of muscle involvement. MRI represents an important diagnostic technique useful in differential diagnosis, thanks to the distinctive patterns observed in the distribution of muscular changes between the different muscular diseases.
In the last decade, distributed generation, with its various technologies, has increased its presence in the energy mix presenting distribution networks with challenges in terms of evaluating the ...technical impacts that require a wide range of network operational effects to be qualified and quantified. The inherent time-varying behavior of demand and distributed generation (particularly when renewable sources are used), need to be taken into account since considering critical scenarios of loading and generation may mask the impacts. One means of dealing with such complexity is through the use of indices that indicate the benefit or otherwise of connections at a given location and for a given horizon. This paper presents a multiobjective performance index for distribution networks with time-varying distributed generation which consider a number of technical issues. The approach has been applied to a medium voltage distribution network considering hourly demand and wind speeds. Results show that this proposal has a better response to the natural behavior of loads and generation than solely considering a single operation scenario.
Energy policies and technological progress in the development of wind turbines have made wind power the fastest growing renewable power source worldwide. The inherent variability of this resource ...requires special attention when analyzing the impacts of high penetration on the distribution network. A time-series steady-state analysis is proposed that assesses technical issues such as energy export, losses, and short-circuit levels. A multiobjective programming approach based on the nondominated sorting genetic algorithm (NSGA) is applied in order to find configurations that maximize the integration of distributed wind power generation (DWPG) while satisfying voltage and thermal limits. The approach has been applied to a medium voltage distribution network considering hourly demand and wind profiles for part of the U.K. The Pareto optimal solutions obtained highlight the drawbacks of using a single demand and generation scenario, and indicate the importance of appropriate substation voltage settings for maximizing the connection of DWPG.
A prospective cohort study was conducted in Italy in order to describe the microbiologic aspects of colonization/infection by carbapenemase-producing Enterobacteriaceae (CPE) in donors and recipients ...of lung and liver transplants and the possible CPE transmission from donors to recipients.
Between 15 January 2014 and 14 January 2015, all recipients of solid organ transplants (SOT) at ten lung and eight liver transplantation centres and the corresponding donors were enrolled. Screening cultures to detect CPE were performed in donors, and screening and clinical cultures in recipients with a 28-day microbiologic follow-up after receipt of SOT. Detection of carbapenemase genes by PCR, genotyping by multilocus sequence typing, and pulsed-field gel electrophoresis and whole-genome sequencing were performed.
Of 588 screened donors, 3.4% were colonized with CPE. Of the liver first transplant recipients (n = 521), 2.5% were colonized before receipt of SOT and 5% acquired CPE during follow-up. CPE colonization was higher in lung first transplant recipients (n = 111, 2.7% before SOT and 14.4% after SOT). CPE infections occurred in 1.9% and 5.3% of liver or lung recipients, respectively. CPE isolates were mostly Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae belonging to CG258. Three events of donor–recipient CPE transmission, confirmed by whole-genome sequencing and/or pulsed-field gel electrophoresis, occurred in lung recipients: two involving K. pneumoniae sequence type 512 and one Verona integron-encoded metallo-β-lactamase (VIM)-producing Enterobacter aerogenes.
This study showed a low risk of donor–recipient CPE transmission, indicating that donor CPE colonization does not necessarily represent a contraindication for donation unless colonization regards the organ to be transplanted. Donor and recipient screening remains essential to prevent CPE transmission and cross-infection in transplantation centres.
Diagnosing aldosterone-producing adenoma (APA) involves a demonstration of the lateralization of aldosterone oversecretion because adrenal incidentalomas are common in hypertensive individuals and ...many small-sized APA escape identification with available imaging techniques. However, because of the pulsatile pattern of aldosterone secretion this can be a difficult undertaking. Stimulation of aldosterone secretion before adrenal vein sampling (AVS) can overcome this difficulty, but anecdotal data exist. We, therefore, prospectively investigated the usefulness of AVS with dynamic testing in primary aldosteronism (PA) patients.
We enrolled 24 consecutive consenting patients with a biochemical diagnosis of PA from a tertiary referral centre to measure the effects of adrenocorticotrophic hormone (ACTH) on selectivity, the lateralization of aldosterone secretion to the APA side, and adverse effects. After correcting the hypokalemia we performed bilateral AVS. After 3 h supine resting, blood was simultaneously obtained from both sides. A high-dose ACTH (250 mug intravenous) bolus was then administered and AVS was repeated after 30 min.
AVS was bilaterally selective in 88% of patients; no adverse effects occurred. Of the 21 patients with bilaterally selective AVS, three had idiopathic hyperaldosteronism and 18 an APA that was surgically removed in 12 with an ensuing fall in blood pressure at follow-up. After ACTH patients showed a significant increase (P = 0.007) of aldosterone from contralateral adrenal vein blood, but not from the APA gland. Therefore, lateralization of aldosterone secretion on the APA side did not improve.
AVS is safe and accurate for identifying APA. However, at a statistical power of 99%, these results do not support the usefulness of high-dose ACTH testing to improve the diagnostic accuracy of AVS.
We evaluated factors affecting long-term survival after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) complicating cirrhosis. One hundred eighty-two patients with ...Child's class A or B cirrhosis and an HCC, not amenable to surgery or percutaneous ethanol injection, underwent 346 TACEs (mean 1.9) with epirubicin, iodized oil, and gelatin sponge. Many prognostic factors were subjected to univariate analysis and thereafter, when significant, to the Cox's hazard proportional model. Finally, the significant indices in the Cox's model were used to estimate the accuracy of the probability of death with computation of the area under the receiving operative characteristic (ROC) curve. The cumulative survival rates at 1, 2, 3, and 5 years were 0.83, 0.52, 0.40, and 0.16, respectively. According to Cox's model, the factors associated with significantly worse survival were the presence of ascites (p = 0.0027), elevated bilirubin levels (p = 0.0163), elevated alpha-fetoprotein (alphaFP) values (p = 0.0067), a tumor greater than 5 cm in diameter (p = 0.0001), and the absence of a tumor capsule-like rim (p = 0.0278). According to these parameters, the accuracy of the probability of death estimated with ROC analysis was 0.63. Minor and major complications occurred in 82 patients (45%) and caused death in 2 patients. Long-term prognosis after TACE for HCCs in patients with Child's class A or B cirrhosis depends on the presence of ascites, the bilirubin level, the alphaFP value, the diameter of the tumor, and the presence of a tumor capsule-like rim. However, when considered altogether, these variables are poor predictors to evaluate survival, and other factors should be investigated to identify subjects more responsive to TACE. Complications occur in a high percentage of patients, but they do not affect long-term prognosis.
Abstract
Aims
To estimate prevalence of atrial fibrillation (AF) in a representative sample of the Italian elderly population, projecting figures for Italy and the European Union.
Methods and results
...A cross-sectional examination of all subjects aged 65+ years from three general practices in Northern, Central, and Southern Italy started in 2016. Participants were administered a systematic and an opportunistic screening, followed by clinical and electrocardiogram confirmation. The study sample included 6016 subjects. Excluding 235 non-eligible, among the remaining 5781 participation was 78.3%, which left 4528 participants (mean age 74.5 ± 6.8 years, 47.2% men). Prevalence of AF was 7.3% 95% confidence intervals (CI) 6.6–8.1, higher in men and with advancing age (6.6% from systematic plus 0.7% from opportunistic screening). Using prevalence figures, Italian elderly having AF in 2016 were estimated at ∼1 081 000 (95% CI 786 000–1 482 000). Considering stable prevalence, this number will increase by 75% to ∼1 892 000 in 2060 (95% CI 1 378 000–2 579 000). European Union elderly having AF in 2016 were estimated at ∼7 617 000 (95% CI 5 530 000–10 460 000), increasing by 89% to ∼14 401 000 in 2060 (95% CI 10 489 000–19 647 000). In 2016, subjects aged 80+ years represented 53.5% of cases in Italy and 51.2% in the European Union; in 2060, 69.6% and 65.2%, respectively.
Conclusions
Our findings indicate a high burden of AF in coming decades, especially among the oldest-old, who carry the higher AF-related risk of stroke and medical complications.
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