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Cost of annual energy loss occurs in distribution networks is an important issue in distribution systems planning, design and operation & discos are pleased to be informed about financial worth of loss extract from their profit to evaluate economic feasibility of improvement projects. there are several dominating factors involved in distribution loss cost evaluation, but most of the times price of loss occurs in distribution systems is calculated regardless of location, consumption pattern and etc, but recent changes in Iran distribution power system including removing energy subsidies, deregulation, increase in distributed generation units and trend toward loss reduction had been resulted in much more importance to have actual price of distribution network losses. In this paper, Distributed generation units penetration level influence on distribution networks worth of loss is investigated, power delivered to distribution systems from these resources is directly connected to loads and no transmission cost is involved, in the proposed formulation this difference between centralized and decentralized generation is covered. It is shown that distribution worth of loss follow a U-shape trajectory by increase in distributed generation units' penetration level.

Today, the interest on distributed generation has been increasing, especially due to technical development on generation systems that meet environmental and energy policy concerns. One of the most important distributed energy technologies is Combined Heat and Power (CHP). CHP is small and self-contained electric generation plan that can provide power for household applications, commercial or industrial facilities and hence its applications are overtly increasing. It can reduce power loss and enhance service reliability in distribution systems. One of the influential factors for the users is the purchasing cost of CHP which is largely dependent on its type, capacity and efficiency. Therefore among all exciting of the commercial CHP technologies certain economic choices are to be taken into account. Cost-Benefit analysis is one of the famous approaches aiming at maximization of benefit-to-cost ratio. The proposed method in this paper determine the optimized size of CHP for users by considering an integrated view of electricity and natural gas network based on the novel concept of energy hubs. The benefits of CHP placement equipped with a heat storage device described in this paper include power cost saving, power loss reduction, reliability enhancement and environmental considerations. At last to confirm the proposed method the best size of CHP is determined for a hotel as a case study.

Today, the interest on distributed generation has been increasing, especially due to technical development on generation systems that meet environmental and energy policy concerns. One of the most important distributed energy technologies is Combined Heat and Power (CHP). CHP is small and self-contained electric generation plan that can provide power for household applications, commercial or industrial facilities and hence its applications are overtly increasing. It can reduce power loss and enhance service reliability in distribution systems. One of the influential factors for the users is the purchasing cost of CHP which is largely dependent on its type, capacity and efficiency. Therefore among all exciting of the commercial CHP technologies certain economic choices are to be taken into account. Cost-Benefit analysis is one of the famous approaches aiming at maximization of benefit-to-cost ratio. The proposed method in this paper determine the optimized size of CHP for users by considering an integrated view of electricity and natural gas network based on the novel concept of energy hubs.

A hundred elderly dyspeptic patients were studied to assess the prevalence of Helicobacter pylori infection and the correlation between histological and serological findings. Eighty-one per cent of the patients with gastritis and 63% with gastric ulcer were H. pylori positive. All patients who had H. pylori negative gastritis and gastric ulcers were on nonsteroidal anti-inflammatory drugs (NSAIDs). There were 24 patients who had evidence of H. pylori infection and were on NSAIDs. H. pylori positive patients had more dyspeptic symptoms in comparison with those who were H. pylori negative. In patients who were taking NSAIDs, the presence of severe active gastritis seemed to correlate with the presence of H. pylori but not with the use of NSAIDs. Serology had a sensitivity of 90% and a specificity of 93% with a negative predictive value of 86%. There was a significant correlation between IgG titre and the degree of inflammation and H. pylori infection. We conclude that H. pylori gastritis is the commonest histopathological finding in elderly dyspeptic patients. H. pylori infection may be an important risk factor in elderly patients who take NSAIDs, increasing their risk of gastric ulcer. H. pylori serology in elderly people has a high sensitivity and specificity comparable with those in young age groups.

SummaryA case of chronic Salmonella enteritidis infection in a young adult patient is reported. Following an initial enteritis with bacteraemia, the illness lasted for a 7-year period and was characterized by recurrent pyrexia, anaemia, weight loss and marked hepatosplenomegaly.Investigations revealed that the patient suffers from a mild form of chronic granulomatous disease presenting in adolescence.

Objectives To audit the specificity and value of the pancreolauryl test (PLT) for the diagnosis of pancreatic insufficiency. Design A retrospective case note review of 47 patients who had a PLT during three consecutive years. Setting A 650 bedded district general hospital. Main outcome measures Patient demographics, symptoms, baseline blood, endoscopic and radiological investigations, and alcohol consumption were related to the results of the PLT to determine if the test could be better targeted. Response to therapy and final diagnoses were noted to determine the specificity of the test. Results Forty seven patients had a PLT during the three years studied. All successfully performed the test as outpatients. Seven inconclusive tests were repeated. Thirty eight patients (81%) had diarrhoea, of whom 10 (21%) described steatorrhoea; 23 (49%) had an abnormal PLT. All with an abnormal test had diarrhoea, more frequently describing watery stools than steatorrhoea. Those treated with pancreatic enzyme supplements had an excellent response, although two of these had a final diagnosis of coeliac disease. Nineteen patients with an abnormal PLT were thought to be suffering from pancreatic insufficiency. All patients with a normal PLT were clinically thought not to have pancreatic insufficiency. Age, sex, and alcohol intake correlated poorly with final diagnosis. Conclusions The PLT can be used in a district general hospital setting as an outpatient test for pancreatic insufficiency and has a specificity of 83%–91%. Its use should be restricted to thse presenting with diarrhoea, not necessarily steatorrhoea, and not restricted to those with a history of high alcohol consumption.

In a retrospective study of 624 elderly patients referred with falls and gait disorders, 45 patients were found to have ataxia. Cerebrovascular diseases were the most common underlying cause of ataxia (15 patients, 37%). Nine patients had hereditary/degenerative cerebellar ataxia. History suggesting alcohol as an underlying cause was established in two patients with cerebellar ataxia. Three patients had normal pressure hydrocephalus and their condition improved remarkably after surgery. No definite cause was found in five patients. Cranial computed tomography (CT) showed cerebral atrophy in 16 patients and in three patients there was evidence of atrophy of the cerebellar vermis. Four patients had femoral neck fractures and three patients had other fractures. In a 5-year follow-up five patients died with bronchopneumonia (11% mortality) and patients with dementia showed rapid deterioration. All patients were referred to the day hospital for rehabilitation. The best treatment outcome was achieved in patients who had a single cerebrovascular accident with no cognitive impairment and in those whose ataxia was secondary to medication. Fourteen patients (44%) moved to residential care while 27 (66%) continued to live in their homes with community support. We concluded that there is no evidence of increased mortality in the elderly patients with cerebellar ataxia. CT scan is mainly helpful in diagnosing specific diseases such as tumours or hydrocephalus. A significant proportion of elderly patients with ataxia may have reversible or treatable conditions and can pursue an independent life.

A case of an elderly female patient, presented with a rare association of primary hyperparathyroidism and renal cell carcinoma, is reported. As a common finding in the elderly, the patient had mild hypercalcaemia for many years but she developed several complications from untreated hyperparathyroidism. The mechanisms of malignant hypercalcaemia are discussed and the importance of properly investigating and managing symptomatic primary hyperparathyroidism in the elderly is emphasised.

Two cases of cardiac syncope with epileptiform features are reported. The patients had been on carbamazepine for many months with increasing frequency of attacks until sinus arrest was documented. Their symptoms disappeared completely with permanent pacemaker implantation and anticonvulsant therapy withdrawal.

A retrospective study of upper gastrointestinal endoscopy (GIE) in 217 octogenarians performed over a two-year period in a district general hospital was carried out. It showed that upper GIE in octogenarians is a safe and easy as in other age groups, and provides more useful information. Patients were referred mainly by the geriatricians for elective endoscopy, reflecting the growing recognition of the value of elective upper GIE in the very elderly. The incidence of peptic ulcer disease as a cause of upper GI bleeding was much less than previously reported. Thirty-nine patients with upper GI haemorrhage had an endoscopy within 24 hours. We believe that this helps to identify patients with a high risk of mortality and those who might benefit from early surgery. Eighty per cent of the patients had one or more associated diseases, but there were no complications from endoscopy. We would like to emphasise that there is no contraindication for upper GIE in very elderly patients.

Sixty-three hyperthyroid patients received ablative dosages of radio iodine. The efficacy of this treatment and the follow-up were assessed one to two and a half years later from case records and general practitioners. Fifty-seven percent of patients were hypothyroid at six months and 65% at one year; 4.8% had failed to become euthyroid within one year; 68.2% of patients were on thyroxine at the time of survey. Two patients had not been seen by their doctor for follow-up and one patient stopped her thyroxine. Most general practitioners preferred patients to be returned to their care once thyroxine treatment was stabilised. Rapid responses and predictable outcome are important advantages of this form of therapy over established methods of management. Intentional ablation is particularly convenient in situations where clinical and biochemical follow-up may be difficult. Good communications and a computer-controlled recall system should ensure effective follow-up.

Summary Published data on the use of transtelephonic electrocardiographic monitoring for evaluation of episodic symptoms suggestive of cardiac arrhythmia are sparse and conflicting. We have reviewed the use of one such device ‘Cardiomemo’ on our unit over an 18 month period. The study showed that transtelephonic electrocardiographic monitoring is useful in documentation of infrequent or sporadic episodes directly related to symptoms when 24-hour ambulatory electrocardiograph monitoring is normal.

Summary A 30 year old male patient with thyrotoxic crisis presenting as status epilepticus is reported. The aetiology, manifestations and management of this medical emergency are discussed. The importance of prompt, vigorous and comprehensive treatment of thyrotoxic crisis is emphasized. Rapid control of hyperthyroidism as well as other supportive measures are essential if the high fatality rate is to be reduced. Comprehensive management reduces mortality from 90% to 20%.

1. The total sialic acid content of human gastric aspirates was measured using a colorimetric assay. Care was taken to optimize the assay and to eliminate interference. 2. The sialic acid content of gastric aspirates collected under resting conditions from 77 patients with non-ulcer dyspepsia was found to decrease with age from >100 μg/ml at 25 years and younger to 3. Analysis of the sialic acids by gas chromatography, mass spectrometry and thin-layer chromatography showed the presence of N-acetylneuraminic acid and two O-acylated derivatives, 9-O-acetyl- and 9-O-lactyl-N-acetylneuraminic acids. These forms were predominantly glycosidically bound. 4. Thin-layer chromatographic analysis of individual aspirate samples showed that the O-acetylated sialic acids were present in all samples, with a maximum of 25% and a minimum of 5% of the total sialic acids.