Evaluating the Efficacy of Primary Treatment for Graves’ Disease Complicated by Thyrotoxic Periodic Paralysis

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Rita Yuk-Kwan Chang

2014-01-01

Full Text Available Objective. Thyrotoxic periodic paralysis (TPP is a potentially life-threatening complication of Graves’ disease (GD. The present study compared the long-term efficacy of antithyroid drugs (ATD, radioactive iodine (RAI, and surgery in GD/TPP. Methods. Sixteen patients with GD/TPP were followed over a 14-year period. ATD was generally prescribed upfront for 12–18 months before RAI or surgery was considered. Outcomes such as thyrotoxic or TPP relapses were compared between the three modalities. Results. Eight (50.0% patients had ATD alone, 4 (25.0% had RAI, and 4 (25.0% had surgery as primary treatment. Despite being able to withdraw ATD in all 8 patients for 37.5 (22–247 months, all subsequently developed thyrotoxic relapses and 4 (50.0% had ≥1 TPP relapses. Of the four patients who had RAI, two (50% developed thyrotoxic relapse after 12 and 29 months, respectively, and two (50.0% became hypothyroid. The median required RAI dose to render hypothyroidism was 550 (350–700 MBq. Of the 4 patients who underwent surgery, none developed relapses but all became hypothyroid. Conclusion. To minimize future relapses, more definitive primary treatment such as RAI or surgery is preferred over ATD alone. If RAI is chosen over surgery, a higher dose (>550 MBq is recommended.

Hypokalemic Periodic Paralysis: a case report and review of the literature

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Soule, Benjamin R; Simone, Nicole L

2008-01-01

Hypokalemic Periodic Paralysis is one form of Periodic Paralysis, a rare group of disorders that can cause of sudden onset weakness. A case of a 29 year old male is presented here. The patient presented with sudden onset paralysis of his extremities. Laboratory evaluation revealed a markedly low potassium level. The patient's paralysis resolved upon repletion of his low potassium and he was discharged with no neurologic deficits. An association with thyroid disease is well established and further workup revealed Grave's disease in this patient. Although rare, Periodic Paralysis must differentiated from other causes of weakness and paralysis so that the proper treatment can be initiated quickly. PMID:18939979

Cisplatin-induced hypokalemic paralysis.

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Mohammadianpanah, Mohammad; Omidvari, Shapour; Mosalaei, Ahmad; Ahmadloo, Niloofar

2004-08-01

Profound hypokalemic conditions resulting from cisplatin therapy have been known to produce hypokalemic paralysis in rare cases. We describe such a case of cisplatin-induced hypokalemic paralysis. A 15-year-old Persian girl with ovarian dysgerminoma presented with severe generalized weakness and paraplegia 1 week after the fourth course of cisplatin-based chemotherapy. On physical examination, there was symmetric flaccid paralysis and areflexia in all of the extremities and particularly in the lower limbs. Her serum potassium concentration was 1.7 mmol/L. Metastatic disease was excluded by a comprehensive systemic evaluation. Complete clinical and paraclinical recovery was achieved after short-term administration of potassium supplement. Adverse drug reactions are common with cisplatin, but the drug is only rarely associated with hypokalemic paralysis. Based on the Naranjo causality algorithm, an objective assessment revealed cisplatin to be a probable cause of hypokalemic paralysis in this case. This adverse drug event--whether isolated or secondary to hypomagnesemia--may be deceptive, leading to a fatal mistake in the oncology setting, and should therefore be precisely differentiated from cancer-related complications. This case suggests that cisplatin should be added to the list of agents causing hypokalemic paralysis. Regular serum electrolyte measurement, the early detection of cation deficiency, and appropriate replacement of cations are all recommended.

Renal tubular dysfunction presenting as recurrent hypokalemic periodic quadriparesis in systemic lupus erythematosus

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D Prasad

2014-01-01

Full Text Available We report recurrent hypokalemic periodic quadriparesis in a 30-year-old woman. Patient had also symptoms of multiple large and small joint pain, recurrent oral ulceration, photosensitivity and hair loss that were persisting since last 6 months and investigations revealed systemic lupus erythematosus (SLE with distal tubular acidosis. Our patient was successfully treated with oral potassium chloride, sodium bicarbonate, hydroxychloroquine and a short course of steroids. Thus, tubular dysfunction should be carefully assessed in patients with SLE.

Practical aspects in the management of hypokalemic periodic paralysis

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Levitt Jacob O

2008-04-01

Full Text Available Abstract Management considerations in hypokalemic periodic paralysis include accurate diagnosis, potassium dosage for acute attacks, choice of diuretic for prophylaxis, identification of triggers, creating a safe physical environment, peri-operative measures, and issues in pregnancy. A positive genetic test in the context of symptoms is the gold standard for diagnosis. Potassium chloride is the favored potassium salt given at 0.5–1.0 mEq/kg for acute attacks. The oral route is favored, but if necessary, a mannitol solvent can be used for intravenous administration. Avoidance of or potassium prophylaxis for common triggers, such as rest after exercise, high carbohydrate meals, and sodium, can prevent attacks. Chronically, acetazolamide, dichlorphenamide, or potassium-sparing diuretics decrease attack frequency and severity but are of little value acutely. Potassium, water, and a telephone should always be at a patient's bedside, regardless of the presence of weakness. Perioperatively, the patient's clinical status should be checked frequently. Firm data on the management of periodic paralysis during pregnancy is lacking. Patient support can be found at http://www.periodicparalysis.org.

Thyrotoxic crisis presenting with jaundice.

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Wickramasinghe, R D S S; Luke, W A N V; Sebastiampillai, B S; Gunathilake, M P M L; Premaratna, R

2016-06-23

Thyrotoxic crisis is a medical emergency requiring early diagnosis and urgent management, which can be challenging due to its diverse clinical presentations. While common presentations include fever, sweating, palpitations, tremors and confusion, presence of jaundice is rare. We report a 35-year-old male who presented with jaundice due to cholestasis along with other features of thyrotoxic crisis due to Graves' disease. He had a good clinical recovery with resolution of cholestasis following treatment for thyrotoxic crisis. Jaundice can be a rare manifestation of thyrotoxic crisis, and should be considered in the differential diagnosis when other clinical features of thyrotoxic crisis are present. However secondary causes of jaundice should be looked into and excluded.

[Thyrotoxic periodic paralysis--an unusual complication of hyperthyroidism].

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Mellgren, Gunnar; Holm, Pål Ivar; Lien, Ernst Asbjørn; Bleskestad, Inger H; Aanderud, Sylvi; Bindoff, Laurence

2002-04-20

Thyrotoxic periodic paralysis (TPP) is a complication of hyperthyroidism. We describe two patients with TPP. A 26-year-old man from Vietnam had weight loss, tachycardia, palpitations and heat intolerance for five months. Episodic leg and arm weakness developed three months after debut of symptoms. The second patient, a 23-year old woman from the Philippines, had had episodic leg weakness in the evenings after dinner for three weeks. Her attacks resolved spontaneously overnight. Physical examination of both patients revealed tachycardia and symmetrical proximal weakness involving both arms and legs. ECG and electrolyte analysis indicated a severe hypokalaemia; thyroid function tests showed hyperthyroidism. Both patients were diagnosed as having Graves' thyrotoxicosis and TPP. They were initially treated with propranolol and subsequently with carbimazole. The first patient had recurrence of thyrotoxicosis and paralysis after 16 months, whereas the second patient has remained symptom-free. TPP is most common in Asian males, very few cases are reported in females. In Western countries TPP is rare, but with increasing immigration, TPP is likely to occur more frequently.

Thyrotoxic periodic paralysis associated with transient thyrotoxicosis due to painless thyroiditis.

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Oh, Sang Bo; Ahn, Jinhee; Oh, Min Young; Choi, Bo Gwang; Kang, Ji Hyun; Jeon, Yun Kyung; Kim, Sang Soo; Kim, Bo Hyun; Kim, Yong Ki; Kim, In Joo

2012-07-01

Thyrotoxic periodic paralysis (TPP) is a rare manifestation of hyperthyroidism characterized by muscle weakness and hypokalemia. All ethnicities can be affected, but TPP typically presents in men of Asian descent. The most common cause of TPP in thyrotoxicosis is Graves' disease. However, TPP can occur with any form of thyrotoxicosis. Up to our knowledge, very few cases ever reported the relationship between TPP and painless thyroiditis. We herein report a 25-yr-old Korean man who suffered from flaccid paralysis of the lower extremities and numbness of hands. The patient was subsequently diagnosed as having TPP associated with transient thyrotoxicosis due to painless thyroiditis. The paralytic attack did not recur after improving the thyroid function. Therefore, it is necessary that early diagnosis of TPP due to transient thyrotoxicosis is made to administer definite treatment and prevent recurrent paralysis.

Etiological spectrum of hypokalemic paralysis: A retrospective analysis of 29 patients

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Ravindra Kumar Garg

2013-01-01

Full Text Available Background: Hypokalemic paralysis is characterized by episodes of acute muscle weakness associated with hypokalemia. In this study, we evaluated the possible etiological factors in patients of hypokalemic paralysis. Materials and Methods: We reviewed the records of 29 patients who were admitted with a diagnosis of hypokalemic paralysis. Modified Guillain-Barre΄ Syndrome disability scale was used to grade the disability. Results: In this study, 15 (51.7% patients had secondary causes of hypokalemic paralysis and 14 patients (42.3% had idiopathic hypokalemic paralysis. Thyrotoxicosis was present in six patients (20.6%, dengue infection in four patients (13.7%, distal renal tubular acidosis in three patients (10.3%, Gitelman syndrome in one patient (3.4%, and Conn′s syndrome in one patient (3.4%. Preceding history of fever and rapid recovery was seen in dengue infection-induced hypokalemic paralysis. Approximately 62% patients had elevated serum creatinine phosphokinase. All patients had recovered completely following potassium supplementation. Patients with secondary causes were older in age, had significantly more disability, lower serum potassium levels, and took longer time to recover. Conclusion: In conclusion, more than half of patients had secondary causes responsible for hypokalemic paralysis. Dengue virus infection was the second leading cause of hypokalemic paralysis, after thyrotoxicosis. Presence of severe disability, severe hypokalemia, and a late disease onset suggested secondary hypokalemic paralysis.

Gitelman′s syndrome presenting with hypocalcemic tetany and hypokalemic periodic paralysis

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Kunal Gandhi

2016-01-01

Full Text Available Gitelman′s syndrome is an autosomal recessive renal tubular disorder characterized by hypomagnesemia, hypokalemia, hypocalciuria, and metabolic alkalosis. Hypocalcemic tetany as a presentation of Gitelman′s syndrome has rarely been reported in literature. We report a rare case of Gitelman′s syndrome presenting with hypocalcemic tetany along with hypokalemic periodic paralysis. A 17-year-old female was admitted to our hospital with a history of perioral numbness and carpal spasms of five days duration with progressive quadriparesis developing over a period of few hours. Past history was significant for three episodes of transient lower limb weakness. On examination, blood pressure was 110/70 mm Hg. Chvostek′s sign and Trousseau′s sign were positive. Neurologically, she was fully oriented. She had Grade 3 power in all the four limbs with intact sensation. Laboratory tests showed hypocalcemia (7.8 mg/dL, hypokalemia (2.2 mEq/L, hypomagnesemia (0.9 mEq/L, and hypocalciuria (104 mg/day. Arterial blood gas showed mild metabolic alkalosis with respiratory compensation. Thus, a clinical diagnosis of GS was made. The patient made a remarkable recovery after the correction of electrolyte imbalance. The aim of this case report is to re-emphasize the fact that hypocalcemia can rarely occur in Gitelman′s syndrome.

Effects of sex steroid hormones, thyroid hormone levels, and insulin regulation on thyrotoxic periodic paralysis in Chinese men

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Li, Wang; Changsheng, Chen; Jiangfang, Fu; Bin, Gao; Nanyan, Zhang; Xiaomiao, Li; Deqiang, Li; Ying, Xing; Wensong, Zai; Qiuhe, Ji

2010-01-01

Our study is to determine the expression of thyroid hormone, sex hormone, insulin, and C-peptide in Chinese male patients with thyrotoxic periodic paralysis (TPP). This study covered 102 patients with hyperthyroidism from Xijing Hospital. According to whether occurrence of TPP or not, patients were divided into two groups (those that were hyperthyroid with and without TPP) that were, matched with age, blood pressure, urea, and creatinine. We found the body mass index (BMI) in patients with TP...

Thyrotoxic periodic paralysis in a Saudi patient complicated by life-threatening arrhythmia

International Nuclear Information System (INIS)

Aldasouqi, Saleh; Bokhari, Samia A; Khan, Patan M; AlZahrani, Ali S

2009-01-01

Thyrotoxic periodic paralysis (TPP) is rare in non-Orientals, and sporadic case reports were reported world-wide. Eight cases were reported in Arabs, including 3 Saudis. We present an additional case of TPP in a 38-year-old Saudi man, and review the literature on TPP in Arabs. Our patient presented with complete flaccid quadriplegia, 5 weeks after he was diagnosed with Graves' disease that was treated with carbimazole and propranolol. He was hyperthyroid, and his potassium was extremely low (1.5 mmol/L). During initial evaluation in the emergency room, he developed transient asystole manifested by syncope. He was resuscitated and his hypokalemia was corrected, and he had a full recovery. This case emphasizes the notion that TPP can occur in patients of any ethnic background. The development of serious cardiac complications in our patient underscores the importance of early and correct diagnosis of this potentially life-threatening complication of hyperthyroidism. (author)

Tiratricol-induced periodic paralysis: a review of nutraceuticals affecting thyroid function.

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Cohen-Lehman, Janna; Charitou, Marina M; Klein, Irwin

2011-01-01

To review the potential adverse effects of thyroid hormone-based nutraceuticals and describe a case of thyrotoxic periodic paralysis (TPP) after abuse of a dietary supplement containing 3,5,3'-triiodothyroacetic acid (tiratricol). We review the literature on potential dangers and therapeutic misadventures of thyroid hormone-based nutraceuticals and present the clinical, laboratory, and radiologic data of a bodybuilder in whom hypokalemic TPP developed after use of "Triax Metabolic Accelerator". A 23-year-old white man developed lower extremity paralysis, diaphoresis, and palpitations in the setting of low serum potassium levels. Laboratory results showed suppressed thyroid-stimulating hormone, low levels of free and total thyroxine, low total triiodothyronine level, and very low 24-hour radioiodine uptake. The patient ultimately admitted to taking a supplement containing tiratricol for approximately 2 months, and hypokalemic TPP was diagnosed. He was treated with potassium supplementation and a β-adrenergic blocking agent, which completely resolved his symptoms. Results of thyroid function tests normalized or approached normal 1 week after hospitalization, and future use of dietary supplements was strongly discouraged. Despite 2 warnings by the US Food and Drug Administration, products containing tiratricol are still available for sale on the Internet. This report illustrates both an unusual adverse effect of a nutraceutical containing tiratricol and the importance of educating our patients about the risks versus benefits of using these widely available but loosely regulated products.

Case of Thyrotoxic Periodic Paralysis in a Caucasian Male and Review of Literature

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Tina K. Thethi

2014-01-01

Full Text Available Objective. Thyrotoxic periodic paralysis (TPP, a known condition in Asian men, is becoming increasingly common in men from Western countries. Since suspicion for TPP as a differential in diagnosis is of utmost importance to avoid overcorrection of hypokalemia and other complications, we are reporting a case of TPP in a 25-year-old Caucasian male. Methods. The patient presented with intermittent lower extremity weakness after consumption of a large high-carbohydrate meal. Clinical examination revealed diffusely enlarged thyroid gland, no muscle power in lower extremities, tremors, and brisk deep tendon reflexes. Results. Clinical and laboratory findings were consistent with Graves’ disease and the patient had hypokalemia. The patient responded to potassium repletion and was treated with propylthiouracil and propranolol. After treatment with radioactive iodine, the patient developed postablative hypothyroidism for which he was treated with levothyroxine. Conclusion. Since this condition is overlooked by physicians in Western countries, we present a case of TPP in a Caucasian male thus showing the importance of consideration of TPP in Caucasians despite its rare occurrence and the need for prompt diagnosis to avoid the danger of hyperkalemia in management of the paralytic attack in TPP patients.

Hypokalemic Rhabdomyolysis Induced Acute Renal Failure As a Presentation of Coeliac Disease

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Funda Sarı

2012-03-01

Full Text Available Adult coeliac disease commonly presents without classical symptoms as chronic diarrhea and weight loss. We describe the case of a 31-year-old woman with persistent life-threatening hypokalemia, acute renal failure, and acute quadriplegia due to diarrhea that had continued for one month. Although there are cases of coeliac disease diagnosed with hypokalemic rhabdomyolysis in the literature, none of the cases developed acute renal failure. This is the first case in the literature diagnosed with acute renal failure due to hypokalemic rhabdomyolysis as a presentation of coeliac disease. In acute renal failure cases that present with hypokalemic rhabdomyolysis due to severe diarrhea, coeliac disease should be considered as a differential diagnosis despite the negative antigliadin IgA antibody.

Thyrotoxic periodic paralysis

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Rojith Karandode Balakrishnan; Suresh Rama Chandran; Geetha Thirumalnesan; Nedumaran Doraisamy

2011-01-01

This article aims at highlighting the importance of suspecting thyrotoxicosis in cases of recurrent periodic flaccid paralysis; especially in Asian men to facilitate early diagnosis of the former condition. A case report of a 28 year old male patient with recurrent periodic flaccid paralysis has been presented. Hypokalemia secondary to thyrotoxicosis was diagnosed as the cause of the paralysis. The patient was given oral potassium intervention over 24 hours. The patient showed complete recove...

Paralysis as a Presenting Symptom of Hyperthyroidism in an Active Duty Soldier.

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Jennette, John; Tauferner, Dustin

2015-01-01

Thyrotoxic periodic paralysis (TPP) is an endocrine disorder presenting with proximal motor weakness, typically greatest in the lower extremities, hypokalemia, and signs or laboratory findings consistent with hyperthyroidism. The incidence of TPP is highest in Asian males. This is a case report of a 30-year-old male active duty Soldier who presented to the emergency department complaining of several recent episodes of lower extremity paralysis. The patient underwent a workup which included serum and cerebrospinal fluid studies, and was found to be hypokalemic and hyperthyroid. Following consultation with neurology, the patient was admitted to the medicine service and treated for thyrotoxic periodic paralysis with potassium replacement and treatment of his hyperthyroidism. Since achieving a euthyroid state, he has had no recurrences of TPP. This disease should be considered in patients presenting with symmetric motor weakness and hypokalemia, whether or not symptoms of hyperthyroidism are elicited during the review of systems.

Thyrotoxic atrial fibrillation.

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Parmar, Malvinder S

2005-01-04

Atrial fibrillation is the most common cardiac complication of hyperthyroidism and occurs in 15% of patients with hyperthyroidism. It is associated with a higher risk of thromboembolism that often involves the central nervous system. Oral anticoagulation is important in the majority of these patients to prevent thromboembolic complications. These patients require adjustment in the dose of various rate-controlling agents because of increased clearance associated with hyperthyroidism and a decrease in warfarin dosage because of increased clearance of vitamin K-dependent clotting factors. The management of thyrotoxic atrial fibrillation is summarized in this clinical review.

Thyrotoxic Graves' disease with normal thyroidal technetium-99m pertechnetate uptake

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Ikekubo, Katsuji; Hino, Megumu; Ito, Hidetomi; Koh, Toshikiyo; Ishihara, Takashi; Kurahachi, Hiroyuki (Kobe City General Hospital (Japan)); Kasagi, Kanji; Hidaka, Akinari; Mori, Toru

1990-07-01

We saw 24 thyrotoxic Graves' patients with normal thyroidal uptake of technetium-99m pertechnetate ({sup 99m}Tc) out of 201 untreated thyrotoxic Graves' patients seen over 4 years. The clinical and laboratory findings for these patients were studied and analyzed. Thyroid uptake and scintigraphic examinations by means of {sup 99m}Tc, TBII and TSab activity measurement clearly distinguished these patients from other thyrotoxic disorders (destruction-induced thyrotoxicosis and autonomously functioning thyroid lesions). Different from other disorders, these patients had not lower but normal thyroid uptake and also showed diffuse and discrete trapping into the enlarged glands. These patients had significantly smaller goiters, a lower serum thyroid hormone level, and lower TBII and TSab activity, when compared with other high {sup 99m}Tc uptake groups with Graves' disease, and their condition could be easily controlled with small amounts of antithyroid drugs. Our study indicates that thyrotoxic Graves' disease with normal {sup 99m}Tc uptake exists and {sup 99m}Tc uptake study and TBII activity measurement is very useful for the diagnosis. The normal {sup 99m}Tc uptake thyrotoxic Graves' patient might be early stage patients with general Graves' disease and their early discrimination from general Graves' patients is very advantageous for treatment and prognosis. (author).

Thyrotoxic Periodic Paralysis and Polymorphisms of the , , and Genes in Men with Graves Disease

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Suyeon Park

2016-03-01

Full Text Available BackgroundThyrotoxic periodic paralysis (TPP is a rare complication of thyrotoxicosis characterized by acute attacks of muscle weakness and hypokalemia. Recently, variation in several genes was suggested to be associated with TPP. This study evaluated the genetic predisposition to TPP in terms of the β2-adrenergic receptor (ADRB2, androgen receptor (AR, and γ-aminobutyric acid receptor α3 subunit (GABRA3 genes.MethodsThis study enrolled 48 men with Graves disease (GD and TPP, and 48 GD patients without TPP. We compared the frequencies of candidate polymorphisms between the two groups.ResultsThe frequency of the Gly16/Gly16 genotype in ADRB2 was not significantly associated with TPP (P=0.32. More CAG repeats (≥26 in the AR gene were not correlated with TPP (odds ratio [OR], 2.46; 95% confidence interval [CI], 0.81 to 8.09; P=0.08. The allele frequency of the TT genotype in the GABRA3 gene was not associated with TPP (OR, 1.83; 95% CI, 0.54 to 6.74; P=0.41.ConclusionThe polymorphisms in the ADRB2, AR, and GABRA3 genes could not explain the genetic susceptibility to TPP in Korean men with GD.

A cola-induced hypokalemic rhabdomyolysis with electromyographic evaluation: A case report

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Davide Ferrazzoli

2017-02-01

Full Text Available Objective: To report a rare case of hypokalemic rhabdomyolysis induced by the heavy and prolonged ingestion of cola-based beverages, and its uneventful recovery after kalemia normalization. Methods: We report a 38-year-old Caucasian male presented in our emergency room with a recent and progressive weakness of the lower limbs proximal muscles. Results: A dietary history revealed a prolonged ingestion of cola-based beverages. Blood tests showed severe hypokalemia and marked increase in serum creatine phosphokinase. The analysis of cerebrospinal fluid resulted normal. Electromyography was suggestive for a myopathy. The clinical, laboratory and neurophysiological data were evocative for a cola-induced hypokalemic rhabdomyolysis. After kalemia normalization, the improvements of the electromyographic findings paralleled the clinical recovery. Conclusion: Chronic consumption of large amount of cola-based soft drinks may result in severe symptomatic hypokalemia, eventually leading in turn to myopathy. To our knowledge, this is the first description of the electromyographic findings of the cola-induced hypokalemic rhabdomyolysis. An early diagnosis and a prompt treatment appear to be crucial for a benign clinical course.

A cola-induced hypokalemic rhabdomyolysis with electromyographic evaluation: A case report.

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Ferrazzoli, Davide; Sabetta, Annarita; Palamara, Grazia; Caremani, Luca; Capobianco, Marina; Balbi, Pietro; Frazzitta, Giuseppe

2017-01-01

To report a rare case of hypokalemic rhabdomyolysis induced by the heavy and prolonged ingestion of cola-based beverages, and its uneventful recovery after kalemia normalization. We report a 38-year-old Caucasian male presented in our emergency room with a recent and progressive weakness of the lower limbs proximal muscles. A dietary history revealed a prolonged ingestion of cola-based beverages. Blood tests showed severe hypokalemia and marked increase in serum creatine phosphokinase. The analysis of cerebrospinal fluid resulted normal. Electromyography was suggestive for a myopathy. The clinical, laboratory and neurophysiological data were evocative for a cola-induced hypokalemic rhabdomyolysis. After kalemia normalization, the improvements of the electromyographic findings paralleled the clinical recovery. Chronic consumption of large amount of cola-based soft drinks may result in severe symptomatic hypokalemia, eventually leading in turn to myopathy. To our knowledge, this is the first description of the electromyographic findings of the cola-induced hypokalemic rhabdomyolysis. An early diagnosis and a prompt treatment appear to be crucial for a benign clinical course.

Predictive features associated with thyrotoxic storm and management.

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Bacuzzi, Alessandro; Dionigi, Gianlorenzo; Guzzetti, Luca; De Martino, Alessandro Ivan; Severgnini, Paolo; Cuffari, Salvatore

2017-10-01

Thyroid storm (TS) is an endocrine emergency characterized by rapid deterioration, associated with high mortality rate therefore rapid diagnosis and emergent treatment is mandatory. In the past, thyroid surgery was the most common cause of TS, but recent preoperative medication creates a euthyroid state before performing surgery. An active approach during perioperative period could determine an effective clinical treatment of this life-threating diseases. Recently, the Japan Thyroid Association and Japan Endocrine Society developed diagnostic criteria for TS focusing on premature and prompt diagnosis avoiding inopportune e useless drugs. This review analyses predictive features associated with thyrotoxic storm highlighting recent literature to optimize the patient quality of care.

Thyrotoxic and pheochromocytoma multisystem crisis: a case report.

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Suzuki, Kodai; Miyake, Takahito; Okada, Hideshi; Yamaji, Fuminori; Kitagawa, Yuichiro; Fukuta, Tetsuya; Yasuda, Ryu; Tanaka, Yoshihito; Okamoto, Haruka; Nachi, Sho; Doi, Tomoaki; Yoshida, Takahiro; Kumada, Keisuke; Yoshida, Shozo; Ushikoshi, Hiroaki; Toyoda, Izumi; Ogura, Shinji

2017-06-23

Thyrotoxic crisis and pheochromocytoma multisystem crisis are rare, life-threatening, emergency endocrine diseases with various clinical manifestations. Here we report a case of a patient who simultaneously developed thyrotoxic crisis and pheochromocytoma multisystem crisis and required intensive cardiovascular management. A 60-year-old Asian man experienced nausea and vomiting, and subsequently developed dyspnea and cold sweats while farming. His serum free thyroxine, free triiodothyronine, and thyrotropin receptor antibody levels were elevated at 2.9 ng/dL, 7.2 pg/dL, and 4.7 IU/L, respectively. Serum thyrotropin levels were suppressed at less than 0.01 μIU/mL. Thyroid echography demonstrated no thyroid swelling (23 × 43 mm). A whole body computed tomography was performed for systemic evaluation. This revealed exophthalmos and a mass of size 57 × 64 mm in the anterior pararenal space. Based on these findings, we made an initial diagnosis of thyrotoxic crisis secondary to exacerbation of Grave's hyperthyroidism. Treatment was begun with an iodine agent at a dose of 36 mg/day, thiamazole at a dose of 30 mg/day, and hydrocortisone at a dose of 300 mg daily for 3 consecutive days. To control tachycardia, continuous intravenously administered propranolol and diltiazem infusions were given. At the same time, small doses of doxazosin and carvedilol were used for both alpha and beta adrenergic blockade. On hospital day 5, his blood pressure and serum catecholamine concentrations (adrenalin 42,365 pg/mL, dopamine 6409 pg/mL, noradrenalin 72,212 pg/mL) were still high despite higher beta blocker and calcium channel blocker doses. These findings contributed to the diagnosis of pheochromocytoma multisystem crisis with simultaneous thyrotoxic crisis. We increased the doses of doxazosin and carvedilol, which stabilized his hemodynamic status. On hospital day 16, metaiodobenzylguanidine scintigraphy showed high accumulation in the right adrenal gland tumor

Hypokalemic salt-losing tubulopathy with chronic renal failure and sensorineural deafness.

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Jeck, N; Reinalter, S C; Henne, T; Marg, W; Mallmann, R; Pasel, K; Vollmer, M; Klaus, G; Leonhardt, A; Seyberth, H W; Konrad, M

2001-07-01

To characterize a rare inherited hypokalemic salt-losing tubulopathy with linkage to chromosome 1p31. We conducted a retrospective analysis of the clinical data for 7 patients in whom cosegregation of the disease with chromosome 1p31 had been demonstrated. In addition, in 1 kindred, prenatal diagnosis in the second child was established, allowing a prospective clinical evaluation. Clinical presentation of the patients was homogeneous and included premature birth attributable to polyhydramnios, severe renal salt loss, normotensive hyperreninemia, hypokalemic alkalosis, and excessive hyperprostaglandin E-uria, which suggested the diagnosis of hyperprostaglandin E syndrome/antenatal Bartter syndrome. However, the response to indomethacin was only poor, accounting for a more severe variant of the disease. The patients invariably developed chronic renal failure. The majority had extreme growth retardation, and motor development was markedly delayed. In addition, all patients turned out to be deaf. The hypokalemic salt-losing tubulopathy with chronic renal failure and sensorineural deafness represents not only genetically but also clinically a disease entity distinct from hyperprostaglandin E syndrome/antenatal Bartter syndrome. A pleiotropic effect of a single gene defect is most likely causative for syndromic hearing loss.

Hereditary Hypokalemic salt-losing tubular disorders

International Nuclear Information System (INIS)

Peters, M.; Konard, M.; Seyberth, H.W.

2003-01-01

The inherited hypokalemic tubular disorders are frequently summarized under the heading Bartter Syndrome since they share several clinical and biochemical findings such as renal salt wasting, hypokalemic metabolic alkalosis, normal blood pressure despite hypereninemic hyperaldosteronism and hyperplasia of the juxtaglomerular apparatus. However, careful characterization of the clinical phenotype and correlation with the clinical phenotype and the correlation with the underlying molecular basis justifies the differentiation into at least four distinct disease entities: (i) the hyperprostaglandin E syndrome or antenatal variant of Bartter syndrome (HPS/aBS), which is caused by mutations in either the Na-K-2Cl cotransporter or the potassium channel of the medullary thick ascending limb of Henle's loop; (ii) the HPS/aBS with sensorineural deafness which results from inactivating mutation in the Barttin beta-subunit of the renal chloride channels; (iii) the classic Bartter syndrome caused by mutations in the chloride channel of the distal nephron; and (iv)Gitelman's variant of Bartter syndrome which is caused by mutations of the Na-Cl cotransporter of the distal convoluted tubule. This review will summarize the clinical characteristics of these diseases and progress recently made in the identification of the underlying molecular defects that will hopefully add to the current knowledge of the pathogenesis of these diseases. (author)

A case of thyrotoxic periodic paralysis as initial manifestation of Graves' disease in a 16-year-old Korean adolescent

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Se Yong Jung

2014-09-01

Full Text Available Thyrotoxic periodic paralysis (TPP is a rare complication of hyperthyroidism, with recurrent muscle paralysis and hypokalemia that are caused by an intracellular shift of potassium. TPP is relatively common in Asian males, but is extremely rare in children and adolescents, even for those of Asian descent. We describe a 16-year-old Korean adolescent presenting with a two-week history of episodic leg weakness in the morning. He showed sinus tachycardia, lower leg weakness, and hypokalemia. Thyroid function test showed hyperthyroidism, and thyroid ultrasonography revealed a diffuse enlarged thyroid with increased vascularity, consistent with Graves' disease. He was treated with β-adrenergic blocker and antithyroid drugs. He has been symptom free for one year, as his hyperthyroidism has been controlled well with antithyroid drugs. TPP should be considered in children and adolescents with acute paralysis of the lower extremities and hypokalemia.

Periodic paralysis: rare presenting symptom of thyrotoxicosis.

Science.gov (United States)

Correa-Luna, Luis Daniel; Reyes-Ortiz, Luis M; Ramírez-Rivera, José

2006-01-01

Paralysis due to hypokalemia results from an acute shift of potassium into cells or excessive potassium deficit. In the absence of potassium deficit, it is observed in Familial Hypokalemic Periodic Paralysis and in Thyrotoxic Hypokalemic Periodic Paralysis (TPP). This report describes the initial presentation of hyperthyroidism as sudden quadriplegia associated with hypokalemia. A healthy 25-year-old Puerto Rican policeman came to the emergency room with sudden paralysis in the four extremities of five hours evolution. He woke up in the morning and could not get up. The day before admission his legs felt weak, and it was hard to get out of bed. He arrived home at 7:00 PM, ate pasta and vegetables, and went to sleep at 10:00 PM. He had no diarrhea or weight loss, no history of medications or illicit drugs. He has a cousin and an aunt with the diagnosis of hypo-thyroidism. The admission temperature was 36.0 degrees C, pulse 96 per minute, respiratory rate 18 per minute, blood pressure 160/70 mmHg. He was alert and oriented as to time, place and person. He could talk properly and was in no respiratory distress. He had no exophtalmos or lid lag. The thyroid was not enlarged or tender. No pseudoclubbing or pretibial edema was found. There was flaccid paralysis of all extremities, 0/5 legs and 1/5 arms. Deep tendon reflexes could not be elicited. The cranial nerves and sensory examination were normal. The hemogram was within normal limits as were the renal and liver functions. Serum sodium was 140 mEq/L, potassium 1.48 mEq/L, phosphorus 1.4 mEq/L. A random glucose was 155 mg/dl and the arterial Ph was 7.41. The urine potassium was 7.04 mEq/L, sodium 60.8 mg/dl. TSH levelwas < 0.03 ug/d], TUP 50.69% (24-40%), T4 17.6 ug/dl (4.7-11.4 ug/dl) Free T4 Index 28.23. He was managed with intravenous potassium chloride, 80 mEq in a period of seven hours with cardiac monitor. The serum potassium level, after the infusion was completed, was 6.70 mEq/L. No cardiac arrhythmia was

Onset of reversible flaccid quadriplegia during treatment of thyrotoxic crisis.

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Mizokami, Tetsuya; Fukui, Takuko; Imoto, Hirofumi; Fujii, Hiroki; Sato, Yuichi; Nunoi, Kiyohide; Okamura, Ken

2015-01-01

Two unrelated women were hospitalized for thyrotoxic crisis complicated by multiple organ failure. Both patients were treated with antithyroid drugs and hydrocortisone, as well as insulin for hyperglycemia, and underwent mechanical ventilation with sedation. Flaccid quadriplegia became apparent after each patient completely recovered their level of consciousness once sedation was discontinued on days 6 and 15, respectively. Three to six months of rehabilitation was required for the muscle strength to fully improve in both cases. Thyrotoxicosis in addition to critical illness polyneuromyopathy and the administration of glucocorticoid therapy may have contributed to the onset of quadriplegia in these two cases. Flaccid quadriplegia is one of the serious neuromuscular conditions experienced during the treatment of thyrotoxic crisis.

[Thyrotoxic storm and myxedema coma].

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Takasu, N

1999-08-01

Thyrotoxic or hyperthyroid storm is a grave, life-threatening, but relatively infrequent medical emergency. Immediate causes of death in this emergency are severe hyperpyrexia and pulmonary edema associated with arrhythmias, shock, and coma. This emergency is found in Graves' patients most frequently. Myxedema coma is an emergency clinical state caused by severe deficiency of thyroid hormones. This crisis represents the extreme expression of hypothyroidism. While it is quite useful to elicit a history of previous hypothyroidism, thyroid surgery, or radioactive iodine treatment, it is not obtainable.

Thyrotoxic thyroiditis after radiotherapy for Hodgkin's disease

International Nuclear Information System (INIS)

Blitzer, J.B.; Paolozzi, F.P.; Gottlieb, A.J.; Zamkoff, K.W.; Chung, C.T.

1985-01-01

Exposure of the thyroid gland to ionizing radiation has been associated with a variety of abnormalities. Among these are tardive hypothyroidism and an increased risk of developing thyroid nodules and cancer. Although acute thyroiditis has been known to complicate radioactive iodine 131 therapy, it has rarely been associated with external beam irradiation. Thyrotoxic painless thyroiditis developed in two patients after mantle-field irradiation for Hodgkin's disease

[Hypoglycaemic periodic paralysis in hyperthyroidism patients].

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Kratochvíl, J; Masopust, J; Martínková, V; Charvát, J

2008-11-01

Hypokalemic periodic paralysis (HPP) is a rare disorder characterised by acute, potentially fatal atacks of muscle weakness or paralysis. Massive shift of potassium into cells is caused by elevated levels of insulin and catecholamines in the blood. Hypophosphatemia and hypomagnesemia may be also present. Acidobasic status usually is not impaired. HPP occurs as familiar (caused by ion channels inherited defects) or acquired (in patients with hyperthyroidism). On the basis of two clinical cases we present a review of hypokalemic periodic paralysis in hyperthyroid patients. We discuss patogenesis, clinical and laboratory findings as well as the principles of prevention and treatment of this rare disorder.

Channelopathies.

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Kim, June-Bum

2014-01-01

Channelopathies are a heterogeneous group of disorders resulting from the dysfunction of ion channels located in the membranes of all cells and many cellular organelles. These include diseases of the nervous system (e.g., generalized epilepsy with febrile seizures plus, familial hemiplegic migraine, episodic ataxia, and hyperkalemic and hypokalemic periodic paralysis), the cardiovascular system (e.g., long QT syndrome, short QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia), the respiratory system (e.g., cystic fibrosis), the endocrine system (e.g., neonatal diabetes mellitus, familial hyperinsulinemic hypoglycemia, thyrotoxic hypokalemic periodic paralysis, and familial hyperaldosteronism), the urinary system (e.g., Bartter syndrome, nephrogenic diabetes insipidus, autosomal-dominant polycystic kidney disease, and hypomagnesemia with secondary hypocalcemia), and the immune system (e.g., myasthenia gravis, neuromyelitis optica, Isaac syndrome, and anti-NMDA [N-methyl-D-aspartate] receptor encephalitis). The field of channelopathies is expanding rapidly, as is the utility of molecular-genetic and electrophysiological studies. This review provides a brief overview and update of channelopathies, with a focus on recent advances in the pathophysiological mechanisms that may help clinicians better understand, diagnose, and develop treatments for these diseases.

[Some neurologic and psychiatric complications in endocrine disorders: the thyroid gland].

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Aszalós, Zsuzsa

2007-02-18

Thyroid hormones are of primary importance for the perinatal development of the central nervous system, and for normal function of the adult brain. These hormones primarily regulate the transcription of specific target genes. They increase the cortical serotonergic neurotransmission, and play an important role in regulating central noradrenergic and GABA function. Thyroid deficiency during the perinatal period results in mental retardation. Hypothyroidism of the adults causes most frequently dementia and depression. Other less common clinical pictures include myxoedema coma, dysfunction of cerebellum and cranial nerves. Hypothyroidism also increases predisposition of stroke. Peripheral diseases frequently include polyneuropathy, carpal tunnel syndrome, myalgic state, and rarely myokymia. Nearly all the hyperthyroid patients show minor psychiatric signs, and infrequently psychosis, dementia, confusion state, depression, apathetic thyrotoxicosis, thyrotoxic crisis, seizures, pyramidal signs, or chorea occur. The peripheral complications may be indicated by chronic thyrotoxic myopathy, infiltrative ophthalmopathy, myasthenia gravis, periodic hypokalemic paralysis and polyneuropathy. Generalized resistance to thyroid hormone was confirmed in a number of patients with attention deficit-hyperactivity disorder. Significantly elevated antithyroid antibody titers characterize Hashimoto's encephalopathy. This condition is a rare, acute - subacute, serious, life threatening, but steroid-responsive, relapsing-remitting, autoimmune disease.

Baking soda pica: a case of hypokalemic metabolic alkalosis and rhabdomyolysis in pregnancy.

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Grotegut, Chad A; Dandolu, Vani; Katari, Sunita; Whiteman, Valerie E; Geifman-Holtzman, Ossie; Teitelman, Melissa

2006-02-01

We report a case of baking soda pica in a woman at 31 weeks of pregnancy causing severe hypokalemic metabolic alkalosis and rhabdomyolysis. A multigravida at 31 weeks of gestation presented with weakness and muscle pain. She was found to have severe hypokalemic metabolic alkalosis and rhabdomyolysis, with elevation in serum transaminases and hypertension. We initially thought the patient had an atypical presentation of preeclampsia until it was realized that she was ingesting 1 full box of baking soda (454 g sodium bicarbonate) per day. Symptoms and abnormal laboratory findings resolved with discontinuation of the patient's pica practices. Pica is a common but often overlooked practice that can potentially lead to life-threatening disorders. A thorough evaluation of a patient's dietary intake is extremely important, especially in the setting of atypical presentations of disease in pregnancy.

Frequency and risk factors associated with hypomagnesaemia in hypokalemic type-2 diabetic patients

International Nuclear Information System (INIS)

Shardha, A.K.; Vaswani, A.S.; Fraz, A.; Alam, M.T.; Kumar, P.

2014-01-01

Objective: To determine the frequency and factors associated with hypomagnesaemia in hypokalemic type-2 diabetic patients presenting at Civil Hospital, Karachi. Study Design: A cross-sectional study. Place and Duration of Study: Department of Medicine and Diabetic Clinic of Civil Hospital and Dow Medical College, Karachi, from November 2010 to May 2011. Methodology: A total of 358 adult type-2 diabetics with hypokalemia were selected for this study. With aseptic measures, venous blood was collected for serum magnesium, potassium, HDLc, LDLc Triglyceride (TGs) and glycosylated hemoglobin (HbA1c) from each subject after an overnight fasting and was analyzed on Roche Hitachi 820 Photo Spectrometry. The data was analyzed on SPSS version 17 to determine the factors associated with hypomagnesaemia like duration of diabetes, Body Mass Index (BMI), diabetic nephropathy, HDLc, LDLc Triglyceride (TGs) and glycosylated hemoglobin (HbA1c) level. Results: Mean age of study population was 55.62 +- 9.9 years. Most of them (n=228, 63.7%) were males. Out of the 358 subjects, 198 (55.3%) had hypomagnesaemia. There was significant association between hypomagnesaemia with duration of diabetes, Body Mass Index (BMI), diabetic nephropathy, HDLc, LDLc Triglyceride (TGs) and glycosylated hemoglobin (HbA1c) level. Conclusion: Hypomagnesaemia is very common in type-2 diabetic hypokalemic patients. Therefore, it should be routinely sought by the clinicians. Early recognition and subsequent treatment of hypomagnesaemia may help in better glycemic control, may delay the chronic complications and decrease the mortality in diabetic hypokalemic patients. (author)

Hypokalemic Paralysis Complicated by Concurrent Hyperthyroidism and Hyperaldosternoism: A Case Report.

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Hsiao, Yu-Hsin; Fang, Yu-Wei; Leu, Jyh-Gang; Tsai, Ming-Hsein

2017-01-04

BACKGROUND Thyrotoxic periodic paralysis (TPP) is commonly observed in patients with acute paralysis and hyperthyroidism. However, there is a possibility of secondary causes of hypokalemia in such a setting. CASE REPORT Herein, we present the case of a 38-year-old woman with untreated hypertension and hyperthyroidism. She presented with muscle weakness, nausea, vomiting, and diarrhea since one week. The initial diagnosis was TPP. However, biochemistry tests showed hypokalemia with metabolic alkalosis and renal potassium wasting. Moreover, a suppressed plasma renin level and a high plasma aldosterone level were noted, which was suggestive of primary aldosteronism. Abdominal computed tomography confirmed this diagnosis. CONCLUSIONS Therefore, it is imperative to consider other causes of hypokalemia (apart from TPP) in a patient with hyperthyroidism but with renal potassium wasting and metabolic alkalosis. This can help avoid delay in diagnosis of the underlying disease.

Hypokalemic Paralysis Complicated by Concurrent Hyperthyroidism and Chronic Alcoholism: A Case Report.

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Tsai, Ming-Hsien; Lin, Shih-Hua; Leu, Jyh-Gang; Fang, Yu-Wei

2015-09-01

Thyrotoxic periodic paralysis (TPP) is characterized by the presence of muscle paralysis, hypokalemia, and hyperthyroidism. We report the case of a young man with paralysis of the lower extremities, severe hypokalemia, and concurrent hyperthyroidism. TPP was suspected; therefore, treatment consisting of judicious potassium (K+) repletion and β-blocker administration was initiated. However, urinary K+ excretion rate, as well as refractoriness to treatment, was inconsistent with TPP. Chronic alcoholism was considered as an alternative cause of hypokalemia, and serum K+ was restored through vigorous K repletion and the addition of K+ -sparing diuretics. The presence of thyrotoxicosis and hypokalemia does not always indicate a diagnosis of TPP. Exclusion of TPP can be accomplished by immediate evaluation of urinary K+ excretion, acid-base status, and the amount of potassium chloride required to correct hypokalemia at presentation.

Ectopic adrenocorticotropic hormone syndrome presenting as hypokalemic metabolic alkalosis and hypertension

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Mansoor C Abdulla

2016-01-01

Full Text Available The ectopic adrenocorticotropic hormone (ACTH syndrome is an uncommon cause of hypercortisolism, which should be considered in patients with hypokalemic metabolic alkalosis and hypertension in the context of lung neoplasm. We report a 60-year-old male patient with severe hypertension, metabolic alkalosis, and hypokalemia as the initial manifestations of an ACTH-secreting small cell lung carcinoma. Ectopic Cushing's syndrome should always be ruled out in patients with severe hypertension and hypokalemia.

Molecular cloning of ion channels in Felis catus that are related to periodic paralyses in man: a contribution to the understanding of the genetic susceptibility to feline neck ventroflexion and paralysis

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Marlyn Zapata

2014-07-01

Full Text Available Neck ventroflexion in cats has different causes; however, the most common is the hypokalemia associated with flaccid paralysis secondary to chronic renal failure. In humans, the most common causes of acute flaccid paralysis are hypokalemia precipitated by thyrotoxicosis and familial forms linked to mutations in sodium, potassium, and calcium channel genes. Here, we describe the sequencing and analysis of skeletal muscle ion channels in Felis catus that could be related to periodic paralyses in humans, contributing to the understanding of the genetic susceptibility to feline neck ventroflexion and paralysis. We studied genomic DNA from eleven cats, including five animals that were hyperthyroid with hypokalemia, although only one presented with muscle weakness, and six healthy control domestic cats. We identified the ion channel ortholog genes KCNJ2, KCNJ12, KCNJ14, CACNA1S and SCN4A in the Felis catus genome, together with several polymorphic variants. Upon comparative alignment with other genomes, we found that Felis catus provides evidence for a high genomic conservation of ion channel sequences. Although we hypothesized that neck ventroflexion in cats could be associated with a thyrotoxic or familial periodic paralysis channel mutation, we did not identify any previously detected human channel mutation in the hyperthyroid cat presenting hypokalemia. However, based on the small number of affected cats in this study, we cannot yet rule out this molecular mechanism. Notwithstanding, hyperthyroidism should still be considered as a differential diagnosis in hypokalemic feline paralysis.

Thyrotoxic periodic paralysis

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... speaking, or swallowing Falls due to muscle weakness Prevention ... . 13th ed. Philadelphia, PA: Elsevier; 2016:chap 12. Ferri FF. Hyperthyroidism. In: Ferri FF, ed. Ferri's Clinical Advisor 2016 . ...

Thyrotoxic Atrial Fibrillation: Factors Associated with Persistence and Risk of Ischemic Stroke

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Cheuk-Lik Wong

2017-01-01

Full Text Available Background. Atrial fibrillation (AF is one of the commonest cardiovascular manifestations of thyrotoxicosis. A significant proportion of patients have persistent AF which may have long term consequences, for example, ischemic stroke. Methods. We performed a retrospective cohort study in a regional hospital from January 2004 to June 2016 to examine the clinical characteristics and outcomes of thyrotoxic patients who presented with atrial fibrillation and to investigate possible factors associated with persistent atrial fibrillation and ischemic stoke. Results. Among 1918 patients who had a diagnosis of thyrotoxicosis, 133 (6.9% patients presented with AF. Spontaneous sinus conversion occurred in 89 (66.9% patients in which 85 (94% patients developed sinus conversion before or within 6 months after having achieved euthyroidism. The remaining 44 (33.1% had persistent AF. The rate of ischemic stroke was numerically higher among patients who had persistent AF than those with spontaneous sinus conversion (15.9% versus 10.1%; log-rank 0.442, p=0.506. Patients who sustained an ischemic stroke were older (71 ± 11 years versus 62 ± 16 years, p=0.023 and had a trend towards higher CHA2DS2-VASc score (2.9 ± 1.7 versus 2.3 ± 1.7, p=0.153. History of smoking (adjusted odds ratio 4.9, 95% CI [1.8,14.0], p=0.002, a larger left atrial diameter (adjusted odd ratio 2.6, 95% CI [1.2,5.5], p=0.014, and a relatively lower free thyroxine level at diagnosis (adjusted odd ratio 2.1, 95% CI [1.2,3.5], p=0.008 were associated with persistence of AF on multivariate analysis. Conclusion. Persistence of thyrotoxic AF occurred in one-third of patients and spontaneous sinus conversion was unlikely after six months of euthyroidism. High rate of ischemic stroke was observed among patients with persistent thyrotoxic AF and older age. Patients with factors associated with persistent AF, especially older people, should be closely monitored beyond 6 months so that

Hypokalemic paralysis in a middle-aged female with classic Bartter syndrome.

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Chiang, Wen-Fang; Lin, Shih-Hung; Chan, Jenq-Shyong; Lin, Shih-Hua

2014-02-01

Inherited classic Bartter syndrome (cBS) is an autosomal recessive renal tubular disorder resulting from inactivating mutations in the asolateral chloride channel (C1C-Kb) and usually presents in early infancy or childhood with mild to moderate hypokalemia. Profound hypokalemic paralysis in patients with cBS is extremely rare, especially in middle age. A 45-year-old Chinese female patient was referred for evaluation of chronic severe hypokalemia despite regular K+ supplementation (1 mmol/kg/d). She had had two episodes of muscle paralysis due to severe hypokalemia (K+ 1.9 - 2.1 mmol/l) in the past 3 years. She denied vomiting, diarrhea, or the use of laxatives or diuretics. Her blood pressure was normal. Biochemical studies showed hypokalemia (K+ 2.5 mmol/l) with renal potassium wasting, metabolic alkalosis (HCO3- 32 mmol/l), normomagnesemia (Mg2+ 0.8 mmol/l), hypercalciuria (calcium to creatinine ratio 0.5 mmol/mmol; normal < 0.22 mmol/mol), high plasma renin activity, but normal plasma aldosterone concentration. Abdominal sonography revealed neither renal stones nor nephrocalcinosis. Acquired causes of cBS such as autoimmune disease and drugs were all excluded. Molecular analysis of the CLCNKB gene, encoding ClC-Kb, and SLC12A3, encoding the thiazide-sensitive sodium chloride cotransporter (NCC), revealed compound heterozygous mutations in CLCNKB (L335P and G470E) inherited from her parents; her SLC12A3 was normal. These two mutations were not identified in 100 healthy subjects. Her plasma K+ concentration rose to 3 - 3.5 mmol/l after the addition of spironolactone. Inherited cBS may present with hypokalemic paralysis and should be considered in adult patients with hypokalemia and metabolic alkalosis.

Trauma triggering thyrotoxic crisis with lactic acidosis

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Jennifer S Prosser

2015-01-01

Full Text Available Thyrotoxic crisis (TC is defined as a life-threatening exacerbation of the hyperthyroid state that causes multiple autonomic and metabolic disturbances. It is considered to be an endocrine emergency that must be urgently diagnosed and treated. We describe a case of TC precipitated by trauma with a resultant lactic acidosis. The patient is a 24-year-old male with a history of hyperthyroidism who presented to the emergency department following a motor vehicle accident. The patient was initially tachycardic and hypertensive, however, was afebrile. Initial laboratory analysis showed an anion gap of 26, lactic acid 7.6, free T4 5.61 and thyroid stimulating hormone < 0.015. A diagnosis of TC was made, and he was treated with intravenous fluids, propranolol, and methimazole with improvement of tachycardia and lactic acidosis. We discuss the features of this case, which reviews the presentations of TC as well as its metabolic sequelae.

Function of thyroid and hypothalamic-pituitary-thyroid axis in radioiodine treated thyrotoxic patients

International Nuclear Information System (INIS)

Helds, A.; Lerhs, E.; Bolshevica, J.; Ozols, V.

1980-01-01

431 thyrotoxic patients were examined at varying intervals after therapy with 131 I. Relapses of thyrotoxicosis were noted in 30 patients (7%), hypothyroidism in 63 patients (14.4%) and the remaining 338 were euthyroid. A peculiar clinical picture of postradiation hyperthyroidism was ascertained. The euthyroid patients had a lower protein bound iodine concentration than normal individuals (4.9 +- 1.7 and 6.0 +- 1.64 mg/100 ml, respectively) and a negative thyroid response after TRH stimulation in 87 per cent. (author)

Hypokalaemic Periodic Paralysis in a Patient with Subclinical Hyperthyroidism: A Rare Case

OpenAIRE

Hegde, Swati; Shaikh, Mohammed Aslam; Gummadi, Thejaswi

2016-01-01

Thyrotoxic Periodic Paralysis (TPP) is an uncommon disorder. Though many cases of hypokalaemic periodic paralysis are reported in overt hyperthyroidism, hypokalaemic paralysis in subclinical hyperthyroidism is very rare. Subclinical hyperthyroidism is characterised by circulating TSH levels below reference range and normal thyroid hormone levels. We describe a case of 32-year-old Asian male who presented to the emergency department with acute onset weakness and hypokalaemia with no previous h...

Acute Cardiac Failure in a Pregnant Woman due to Thyrotoxic Crisis

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Nao Okuda

2012-01-01

Full Text Available Introduction. Cardiac failure during pregnancy is usually related to preeclampsia/eclampsia, rarely to hyperthyroidism. While hyperthyroidism can easily lead to hypertensive cardiac failure and may harm the fetus, it is sometimes difficult to distinguish hyperthyroidism from normal pregnancy. Case Presentation. We encountered a case of 41-year-old pregnant woman with hypertensive cardiac failure. Because we initially diagnosed as pre-eclampsia/eclampsia, Caesarian section was performed. However, her symptoms still persisted after delivery. After thyroid function test results taken on the day of admission were obtained on the fourth day, we could diagnose that her cardiac failure was caused by thyrotoxic crisis. Conclusions. Hypertensive cardiac failure due to hyperthyroidism during pregnancy is rare and difficult to diagnose because of similar presentation of normal pregnancy. However, physicians should be aware of the risks posed by hyperthyroidism during pregnancy.

THE VALUE OF BEDSIDE ULTRASOUND IN THE DIAGNOSIS OF THYROTOXICOSIS AND THYROTOXIC CARDIAC EMERGENCIES- A SHORT-TERM STUDY

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Muhammed Mushthaque P; Kunhi Kannan

2017-01-01

BACKGROUND Many times in ICU patient’s thyrotoxicosis is suspected and its diagnosis is hindered by many fallacies of clinical examination and lab reports. This happens especially with cardiac emergencies. The role of Ultrasound examination of thyroid in ICU patients admitted for different causes needs to be studied elaborately. AIM To assess the thyrotoxic burden in the ICU of suspected thyroid disease in patients; find out the benefit of thyroid ultrasound in evaluating...

Model of iodine metabolism in a T3-thyrotoxic patient undergoing I-131 therapy

International Nuclear Information System (INIS)

Ahuja, S.; Price, R.; Brill, A.B.; Dobyns, B.M.; Berman, M.

Data on radioactivity in the thyroid, urine, serum, butanol-extractable iodine (BEI) and chromatographic fractionations of BEI, obtained during four I-131 therapeutic treatments of a T 3 -thyrotoxic patient, have been analyzed and simulated with the help of a 7-compartment model. Good fits to most of the data can be obtained with both the dose-independent and dose-dependent models. A model with 3 or 4 compartments, which provides adequate fits to iodine kinetic data in most euthyroid and hyperthyroid patients is not satisfactory in the case of this patient. Thus, to represent iodine metabolism during T 3 -thyrotoxicosis therapy, we find that it is necessary to provide for separate biochemical pathways for the BEI components as well as the butanol-insoluble compounds released by the thyroid gland

Diffuse Lymphomatous Infiltration of Kidney Presenting as Renal Tubular Acidosis and Hypokalemic Paralysis: Case Report

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Jhamb, Rajat; Gupta, Naresh; Garg, Sandeep; Kumar, Sachin; Gulati, Sameer; Mishra, Deepak; Beniwal, Pankaj

2007-01-01

We report the case of a 22-year-old woman who presented with acute onset flaccid quadriparesis. Physical examination showed mild pallor with cervical and axillary lymphadenopathy, hepatomegaly, and bilateral smooth enlarged kidneys. Neurological examination revealed lower motor neuron muscle weakness in all the four limbs with hyporeflexia and normal sensory examination. Laboratory investigations showed anemia, severe hypokalemia, and metabolic acidosis. Urinalysis showed a specific gravity of 1.010, pH of 7.0, with a positive urine anion gap. Ultrasound revealed hepatosplenomegaly with bilateral enlarged smooth kidneys. Renal biopsy was consistent with the diagnosis of non-Hodgkin lymphoma (B cell type). Metabolic acidosis, alkaline urine, and severe hypokalemia due to excessive urinary loss in our patient were suggestive of distal renal tubular acidosis. Renal involvement in lymphoma is usually subclinical and clinically overt renal disease is rare. Diffuse lymphomatous infiltration of the kidneys may cause tubular dysfunction and present with hypokalemic paralysis. PMID:18074421

Model of iodine metabolism in a T₃-thyrotoxic patient undergoing I-131 therapy

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Ahuja, S.; Price, R.; Brill, A. B.; Dobyns, B. M.; Berman, M.

1975-06-01

Data on radioactivity in the thyroid, urine, serum, butanol-extractable iodine (BEI) and chromatographic fractionations of BEI, obtained during four I-131 therapeutic treatments of a T₃-thyrotoxic patient, have been analyzed and simulated with the help of a 7-compartment model. Good fits to most of the data can be obtained with both the dose-independent and dose-dependent models. A model with 3 or 4 compartments, which provides adequate fits to iodine kinetic data in most euthyroid and hyperthyroid patients is not satisfactory in the case of this patient. Thus, to represent iodine metabolism during T₃-thyrotoxicosis therapy, we find that it is necessary to provide for separate biochemical pathways for the BEI components as well as the butanol-insoluble compounds released by the thyroid gland. (auth)

Reversion of thyrotoxic atrial fibrillation in hypothyroid state after radioiodine treatment

International Nuclear Information System (INIS)

Yamamoto, Makiko; Saito, Shintaro; Sakurada, Toshiro; Yoshida, Katsumi; Kaise, Kazuro; Kaise, Nobuko; Fukazawa, Hiroshi; Itagaki, Yoichi; Yoshinaga, Kaoru

1992-01-01

Twenty patients with thyrotoxic Basedow's disease complicated by atrial fibrillation lasting more than one month despite treatment with antithyroidal drugs were treated with radioiodine supplemented with an antithyroidal drug or inorganic iodine. We classified the 20 patients on the basis of strial fibrillation reversion into two groups, one with reversion (group I) and the other without reversion (group II). In all 12 patients in group I, T 4 and T 3 decreased to hypothyroid levels in 3.2±1.3 months, and one month later all patients had their sinus rhythm restored while T 4 and T 3 also remained below normal (2.6±1.1 μg/dl and 77.9±34.4 ng/dl, respectively). Although T 4 and T 3 also decreased within 3.5±1.8 months in all 8 patients in group II, one month later, atrial fibrillation persisted while T 4 and T 3 (10.4±5.3 μg/dl and 157.7±67.5 ng/dl, respectively) rose significantly compared to those in group I (p<0.001 and p<0.01, respectively). For reversion of atrial fibrillation it is important that the onset of hypothyroidism is rapidly induced by radioiodine and that hypothyroidism continues for at least one month. (author)

Acute Thyrotoxic Bulbar Myopathy with Encephalopathic Behaviour: An Uncommon Complication of Hyperthyroidism

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Neeraja J. Boddu

2013-01-01

Full Text Available Objective. Acute thyrotoxic bulbar palsy is rare, severe, and rapidly progressive. We describe a case of thyrotoxicosis with bulbar palsy, encephalopathy, and pyramidal tract dysfunction. Case Report. 64-year-old white male with toxic multinodular goiter presented with rapid atrial fibrillation. He had mild tremor, normal cranial nerve examination, 4/5 strength in all extremities, normal reflexes, and down going plantars. TSH was low at 0.09 (normal: 0.34–5.6 uIU/mL, and free T4 was high at 5.22 (normal: 0.47–1.41 ng/dL. Despite optimal AV nodal blockade, he had persistent rapid atrial fibrillation. He later developed cervical dystonia, rigidity, clonus, dysarthria, dysphagia, vocal cord palsy, and absent gag reflex. Thyroid storm was suspected. Neuroimaging and cerebrospinal fluid cultures were nondiagnostic. Acetylcholine receptor antibodies were negative. Swallow ability was impaired with heavy secretions. Remarkable improvement in symptoms was noted after initiation of treatment for thyroid storm. Conclusion. Pyramidal tract symptoms and bulbar palsy may occur with thyrotoxicosis. Cranial nerve involvement and encephalopathy raise a question of primary brain mechanism causing bulbar palsy. This is reversible with prompt treatment of thyroid storm.

Low-dose spinal-epidural anesthesia for Cesarean section in a parturient with uncontrolled hyperthyroidism and thyrotoxic heart disease.

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Liao, Zhimin; Xiong, Yaqin; Luo, Linli

2016-08-01

A 29-year-old woman at 34 weeks' gestation with uncontrolled hyperthyroidism and thyrotoxic heart disease was admitted to urgency Cesarean section. After preoperative sedation and good communication, low-dose spinal anesthesia (7.5 mg 0.5 % bupivacaine) combined with epidural anesthesia (6 ml 2 % lidocaine) was performed through L3-4 inter-vertebral. Opioids were given intravenously to the mother for sedation after delivery of the baby. Satisfactory anesthesia and sedation was provided during surgery. The mother and the neonate were safe and no special complication was found after surgery. Our case demonstrated that low-dose spinal anesthesia combined with epidural anesthesia with intravenous opioids can provide satisfactory anesthesia and sedation, and reduce the risk of heart failure and thyroid storm.

Reversion of thyrotoxic atrial fibrillation in hypothyroid state after radioiodine treatment

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Yamamoto, Makiko; Saito, Shintaro; Sakurada, Toshiro; Yoshida, Katsumi; Kaise, Kazuro; Kaise, Nobuko; Fukazawa, Hiroshi; Itagaki, Yoichi; Yoshinaga, Kaoru [Tohoku Univ., Sendai (Japan). School of Medicine

1992-06-01

Twenty patients with thyrotoxic Basedow's disease complicated by atrial fibrillation lasting more than one month despite treatment with antithyroidal drugs were treated with radioiodine supplemented with an antithyroidal drug or inorganic iodine. We classified the 20 patients on the basis of strial fibrillation reversion into two groups, one with reversion (group I) and the other without reversion (group II). In all 12 patients in group I, T{sub 4} and T{sub 3} decreased to hypothyroid levels in 3.2{+-}1.3 months, and one month later all patients had their sinus rhythm restored while T{sub 4} and T{sub 3} also remained below normal (2.6{+-}1.1 {mu}g/dl and 77.9{+-}34.4 ng/dl, respectively). Although T{sub 4} and T{sub 3} also decreased within 3.5{+-}1.8 months in all 8 patients in group II, one month later, atrial fibrillation persisted while T{sub 4} and T{sub 3} (10.4{+-}5.3 {mu}g/dl and 157.7{+-}67.5 ng/dl, respectively) rose significantly compared to those in group I (p<0.001 and p<0.01, respectively). For reversion of atrial fibrillation it is important that the onset of hypothyroidism is rapidly induced by radioiodine and that hypothyroidism continues for at least one month. (author).

Reversion of thyrotoxic atrial fibrillation in hypothyroid state after radioiodine treatment

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Yamamoto, Makiko; Saito, Shintaro; Sakurada, Toshiro; Yoshida, Katsumi; Kaise, Kazuro; Kaise, Nobuko; Fukazawa, Hiroshi; Itagaki, Yoichi; Yoshinaga, Kaoru (Tohoku Univ., Sendai (Japan). School of Medicine)

1992-06-01

Twenty patients with thyrotoxic Basedow's disease complicated by atrial fibrillation lasting more than one month despite treatment with antithyroidal drugs were treated with radioiodine supplemented with an antithyroidal drug or inorganic iodine. We classified the 20 patients on the basis of strial fibrillation reversion into two groups, one with reversion (group I) and the other without reversion (group II). In all 12 patients in group I, T{sub 4} and T{sub 3} decreased to hypothyroid levels in 3.2{+-}1.3 months, and one month later all patients had their sinus rhythm restored while T{sub 4} and T{sub 3} also remained below normal (2.6{+-}1.1 {mu}g/dl and 77.9{+-}34.4 ng/dl, respectively). Although T{sub 4} and T{sub 3} also decreased within 3.5{+-}1.8 months in all 8 patients in group II, one month later, atrial fibrillation persisted while T{sub 4} and T{sub 3} (10.4{+-}5.3 {mu}g/dl and 157.7{+-}67.5 ng/dl, respectively) rose significantly compared to those in group I (p<0.001 and p<0.01, respectively). For reversion of atrial fibrillation it is important that the onset of hypothyroidism is rapidly induced by radioiodine and that hypothyroidism continues for at least one month. (author).

Thyrotoxic Myopathy

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... potassium levels (known as periodic paralysis). View Full Definition Treatment Treatment involves restoring normal levels of thyroid hormone and may include thyroid drugs, radioactive iodine, and sometimes partial or complete surgical ...

Learn About Neuromuscular Disease

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... cause weakness and degeneration of the skeletal muscles. Becker muscular dystrophy (BMD) Congenital muscular dystrophies (CMD) Bethlem CMD Fukuyama ... Hyperkalemic periodic paralysis Hypokalemic periodic paralysis Myotonia ... muscular dystrophy Vocal cord and pharyngeal distal myopathy Welander distal ...

Incidence rate of symptomatic painless thyroiditis presenting with thyrotoxicosis in Denmark as evaluated by consecutive thyroid scintigraphies.

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Schwartz, Frederik; Bergmann, Natasha; Zerahn, Bo; Faber, Jens

2013-04-01

Painless thyroiditis (PT) is a transient kind of thyrotoxicosis, with lack of uptake on a thyroid scintigraphy in a non-tender thyroid gland, elevated anti-TPO antibodies, no fever, no history of increased iodine intake, and a normal sedimentation rate. The prevalence of PT varies hugely in the literature. To establish the incidence rate of PT in Denmark as well as to describe the phenotype of PT in more detail. Tc-99m pertechnetate scintigraphies were performed over a period of 9.75 years on 6022 consecutive patients (2349 had a thyrotoxic episode), and were divided into high or normal (5528), reduced (300) or lack of uptake (194). Patient records were evaluated: 292 with reduced, and 186 with lack of uptake. As a control measure, 230 consecutive thyrotoxic patients were also analyzed. Based on scintigraphies, 12 patients had PT, 10 with lack of uptake and two with reduced, corresponding to an incidence rate of 0.49/100,000 person years. It was predicted, that only one patient among the newly diagnosed consecutive thyrotoxic cohort had PT. This patient was identified. The prevalence of PT among thyrotoxic patients was 0.51% as evaluated by scintigraphy, and 0.43% among the biochemically thyrotoxic patient cohort. Twenty-five percent had more than one thyrotoxic episode, 75% had at least one subsequent hypothyroid episode, and 33% developed permanent hypothyroidism. PT presenting with symptomatic thyrotoxicosis is an extremely rare disease in Denmark. Symptomatic PT presents most often with no uptake on a Tc-99m pertechnetate scintigraphy. Clinical follow-up is essential.

T3RU test

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... of a thyroid disorder, including: Hyperthyroidism (overactive thyroid) Hypothyroidism (underactive thyroid) Thyrotoxic periodic paralysis (muscle weakness caused by high levels of thyroid hormone ...

Thyrotoxicosis Presenting as Unilateral Drop Foot.

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Hara, Kenju; Miyata, Hajime; Motegi, Takahide; Shibano, Ken; Ishiguro, Hideaki

2017-01-01

Neuromuscular disorders associated with hyperthyroidism have several variations in their clinical phenotype, such as ophthalmopathy, periodic paralysis, and thyrotoxic myopathy. We herein report an unusual case of thyrotoxic myopathy presenting as unilateral drop foot. Histopathological examinations of the left tibialis anterior muscle showed marked variation in the fiber size, mild inflammatory cell infiltration, and necrotic and regenerated muscle fibers with predominantly type 1 fiber atrophy. Medical treatment with propylthiouracil resulted in complete improvement of the left drop foot. This case expands the phenotype of thyrotoxicosis and suggests that thyrotoxicosis be considered as a possible cause of unilateral drop foot.

Clinical signs of radiologic pneumonia in under-five hypokalemic diarrheal children admitted to an urban hospital in bangladesh.

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Mohammod Jobayer Chisti

Full Text Available BACKGROUND: Clinical signs of pneumonia are often veiled in under-five diarrheal children presenting with hypokalemia, making clinical diagnosis of pneumonia very difficult in such population. However, there is no published report that describes the influences of hypokalemia on the clinical signs of pneumonia in diarrheal children. Our objective was to assess the influences of hypokalemia, and their outcome in such children. METHODS: We prospectively enrolled all under-five diarrheal children (n = 180 admitted to the Special Care Ward of the Dhaka Hospital of icddr,b from September-December 2007 with radiological pneumonia who also had their serum potassium estimated. We compared the clinical features and outcome of the diarrheal children having pneumonia with (cases = 55 and without hypokalemia (controls = 125. RESULTS: The case-fatality among the cases was 2 times higher compared to the controls, but the difference was not statistically significant (p = 0.202. In logistic regression analysis, after adjusting for potential confounders such as age of the patient, clinical dehydration, severe wasting, abnormally sleepy, lower chest wall in-drawing, nasal flaring and inability to drink on admission, under-five diarrheal children with pneumonia who presented with nutritional edema had 3 times more risk to have hypokalemia compared to those without nutritional edema (OR = 2.76, 95% CI = 1.01-7.51 and these hypokalemic children were 64% less likely to present with fast breathing (OR = 0.36, 95% CI = 0.17-0.74. CONCLUSION AND SIGNIFICANCE: The results of our analysis are simple but may have great public health implications and underscore the importance of diligent assessment for pneumonia in under-five diarrheal children having risk of hypokalemia as in children with nutritional edema even in absence of fast breathing, a useful sign of pneumonia. This may help for early initiation of first dose of parental antibiotics

Clinical Signs of Radiologic Pneumonia in Under-Five Hypokalemic Diarrheal Children Admitted to an Urban Hospital in Bangladesh

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Chisti, Mohammod Jobayer; Salam, Mohammed Abdus; Ashraf, Hasan; Faruque, Abu S. G.; Bardhan, Pradip Kumar; Das, Sumon Kumar; Shahunja, K. M.; Shahid, Abu S. M. S. B.; Ahmed, Tahmeed

2013-01-01

Background Clinical signs of pneumonia are often veiled in under-five diarrheal children presenting with hypokalemia, making clinical diagnosis of pneumonia very difficult in such population. However, there is no published report that describes the influences of hypokalemia on the clinical signs of pneumonia in diarrheal children. Our objective was to assess the influences of hypokalemia, and their outcome in such children. Methods We prospectively enrolled all under-five diarrheal children (n = 180) admitted to the Special Care Ward of the Dhaka Hospital of icddr,b from September-December 2007 with radiological pneumonia who also had their serum potassium estimated. We compared the clinical features and outcome of the diarrheal children having pneumonia with (cases = 55) and without hypokalemia (controls = 125). Results The case-fatality among the cases was 2 times higher compared to the controls, but the difference was not statistically significant (p = 0.202). In logistic regression analysis, after adjusting for potential confounders such as age of the patient, clinical dehydration, severe wasting, abnormally sleepy, lower chest wall in-drawing, nasal flaring and inability to drink on admission, under-five diarrheal children with pneumonia who presented with nutritional edema had 3 times more risk to have hypokalemia compared to those without nutritional edema (OR = 2.76, 95% CI = 1.01–7.51) and these hypokalemic children were 64% less likely to present with fast breathing (OR = 0.36, 95% CI = 0.17–0.74). Conclusion and significance The results of our analysis are simple but may have great public health implications and underscore the importance of diligent assessment for pneumonia in under-five diarrheal children having risk of hypokalemia as in children with nutritional edema even in absence of fast breathing, a useful sign of pneumonia. This may help for early initiation of first dose of parental antibiotics along with

Clinical characterization and diagnosis of cystic fibrosis through exome sequencing in Chinese infants with Bartter-syndrome-like hypokalemia alkalosis.

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Qiu, Liru; Yang, Fengjie; He, Yonghua; Yuan, Huiqing; Zhou, Jianhua

2018-03-09

Cystic fibrosis (CF) is a fatal autosomal-recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. CF is characterized by recurrent pulmonary infection with obstructive pulmonary disease. CF is common in the Caucasian population but is rare in the Chinese population. The symptoms of early-stage CF are often untypical and may sometimes manifest as Bartter syndrome (BS)-like hypokalemic alkalosis. Therefore, the ability of doctors to differentiate CF from BS-like hypokalemic alkalosis in Chinese infants is a great challenge in the timely and accurate diagnosis of CF. In China, sporadic CF has not been diagnosed in children younger than three years of age to date. Three infants, who were initially admitted to our hospital over the period of June 2013 to September 2014 with BS-like hypokalemic alkalosis, were diagnosed with CF through exome sequencing and sweat chloride measurement. The compound heterozygous mutations of the CFTR gene were detected in two infants, and a homozygous missense mutation was found in one infant. Among the six identified mutations, two are novel point mutations (c.1526G > C and c.3062C > T) that are possibly pathogenic. The three infants are the youngest Chinese patients to have been diagnosed with sporadic CF at a very early stage. Follow-up examination showed that all of the cases remained symptom-free after early intervention, indicating the potential benefit of very early diagnosis and timely intervention in children with CF. Our results demonstrate the necessity of distinguishing CF from BS in Chinese infants with hypokalemic alkalosis and the significant diagnostic value of powerful exome sequencing for rare genetic diseases. Furthermore, our findings expand the CFTR mutation spectrum associated with CF.

Embolic Risk in Atrial Fibrillation that Arises from Hyperthyroidism

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Traube, Elie; Coplan, Neil L.

2011-01-01

Atrial fibrillation, the most common cardiac complication of hyperthyroidism, occurs in an estimated 10% to 25% of overtly hyperthyroid patients. The prevalence of atrial fibrillation increases with age in the general population and in thyrotoxic patients. Other risk factors for atrial fibrillation in thyrotoxic patients include male sex, ischemic or valvular heart disease, and congestive heart failure. The incidence of arterial embolism or stroke in thyrotoxic atrial fibrillation is less clear. There are many reports of arterial thromboembolism associated with hyperthyroidism, including cases of young adults without coexisting risk factors other than thyrotoxic atrial fibrillation. The use of anticoagulative agents to prevent thromboembolic sequelae of thyrotoxic atrial fibrillation is controversial: national organizations provide conflicting recommendations in their practice guidelines. Herein, we review the medical literature and examine the evidence behind the recommendations in order to determine the best approach to thromboembolic prophylaxis in patients who have atrial fibrillation that is associated with hyperthyroidism. PMID:21720457

Embolic risk in atrial fibrillation that arises from hyperthyroidism: review of the medical literature.

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Traube, Elie; Coplan, Neil L

2011-01-01

Atrial fibrillation, the most common cardiac complication of hyperthyroidism, occurs in an estimated 10% to 25% of overtly hyperthyroid patients. The prevalence of atrial fibrillation increases with age in the general population and in thyrotoxic patients. Other risk factors for atrial fibrillation in thyrotoxic patients include male sex, ischemic or valvular heart disease, and congestive heart failure. The incidence of arterial embolism or stroke in thyrotoxic atrial fibrillation is less clear. There are many reports of arterial thromboembolism associated with hyperthyroidism, including cases of young adults without coexisting risk factors other than thyrotoxic atrial fibrillation. The use of anticoagulative agents to prevent thromboembolic sequelae of thyrotoxic atrial fibrillation is controversial: National organizations provide conflicting recommendations in their practice guidelines. Herein, we review the medical literature and examine the evidence behind the recommendations in order to determine the best approach to thromboembolic prophylaxis in patients who have atrial fibrillation that is associated with hyperthyroidism.

Clinical Observations of Abnormal Glucose Tolerance in Hyperthyroidism

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Lee, Kyung Ja; Lee, Hong Kyu [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1969-09-15

Plasma glucose levels before and after oral glucose administration have been compared in g group of 76 thyrotoxic subjects and a group of 8 normal control subjects in order to study the effect of glucose loading in thyrotoxicosis. Following were the results: 1) The mean fasting plasma glucose level was elevated in thyrotoxic group (95.5 mg%) compared to normal control group (88 mg%). 2) The peak of glucose tolerance curve is at 30 minutes after glucose administration in both groups, but its mean value was 44 mg% higher in thyrotoxic group than in control group. 3) The plasma glucose levels returned towards the fasting level in the later stage of the test more rapidly in thyrotoxic group than in control group. 4) 69.6% of oral glucose tolerance tests were impaired in the thyrotoxic group, and the occurrence of abnormal glucose tolerance could be related to the degree of thyrotoxicity, sex and age. 5) The mechanisms of the impaired glucose tolerance in thyrotoxicosis are thought to be related to an increased rate of glucose absorption from gastrointestinal tract, abnormal liver function with decreased hepatic glycogenesis, increased glucose oxidation, decreased pancreatic release of insulin, and genetic relationship between diabetes and thyrotoxicosis.

Neuropsychiatric complications of 500 cases of hyperthyroidism

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Moetamedi M

1998-07-01

Full Text Available Hyperthyroidism is often accompanied by diverse types of neuropychiatric complications. To demonstrate these complications we studied 500 hyperthyroid patients, who developed neuropsychiatric complications of hyperthyroidism for which other causes of these neuropsychiatric findings were carefully excluded. The patients were 15 to 65 years old (female to male ratio was 5:1, most of the cases were in third and fourth decades of life. Nervousness, tense dysphoria, insomnia and anxiousness were among the most common psychiatric complications, and tremor, hyperreflexia, thyrotoxic myopathy, thyrotoxic periodic paralysis were the most common neurologic complications. Therefore any physician, wether he or she is a general practitioner or a specialist must be aware of these diverse complications, because these neuropsychiatric complications can lead to the diagnosis of hyperthyroidism and treatment of these potentially serious complications.

Channelopathies

OpenAIRE

Kim, June-Bum

2014-01-01

Channelopathies are a heterogeneous group of disorders resulting from the dysfunction of ion channels located in the membranes of all cells and many cellular organelles. These include diseases of the nervous system (e.g., generalized epilepsy with febrile seizures plus, familial hemiplegic migraine, episodic ataxia, and hyperkalemic and hypokalemic periodic paralysis), the cardiovascular system (e.g., long QT syndrome, short QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ven...

A rare cause of acute flaccid paralysis: Human coronaviruses

OpenAIRE

Turgay, Cokyaman; Emine, Tekin; Ozlem, Koken; Muhammet, S. Paksu; Haydar, A. Tasdemir

2015-01-01

Acute flaccid paralysis (AFP) is a life-threatening clinical entity characterized by weakness in the whole body muscles often accompanied by respiratory and bulbar paralysis. The most common cause is Gullian-Barre syndrome, but infections, spinal cord diseases, neuromuscular diseases such as myasthenia gravis, drugs and toxins, periodic hypokalemic paralysis, electrolyte disturbances, and botulism should be considered as in the differential diagnosis. Human coronaviruses (HCoVs) cause common ...

Dengue-associated neuromuscular complications

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Ravindra Kumar Garg; Hardeep Singh Malhotra; Amita Jain; Kiran Preet Malhotra

2015-01-01

Dengue is associated with many neurological dysfunctions. Up to 4% of dengue patients may develop neuromuscular complications. Muscle involvement can manifest with myalgias, myositis, rhabdomyolysis and hypokalemic paralysis. Diffuse myalgia is the most characteristic neurological symptom of dengue fever. Dengue-associated myositis can be of varying severity ranging from self-limiting muscle involvement to severe dengue myositis. Dengue-associated hypokalemic paralysis often has a rapidly evo...

PRESENT SCENARIO OF NON TRAUMATIC QUADRIPARESIS IN A TEACHING HOSPITAL

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Radha Krishnan

2015-04-01

Full Text Available AIMS & OBJECTIVES: Patients presenting with acute quadriparesis may pose therapeutic challenge to the treating physician especially the development of bulbar palsy and respiratory paralysis and require intensive monitoring and treatment in acute clinical and respiratory care units. So this study was conducted to know the etiology of cases of non - traumatic Quadriparesis and its outcome. MATERIALS AND METHODS: 50 adult patients admitted in medical and neurology wards with non - traumatic quadriparesis were prospectively studied b etween October ’2012 to September ’2014at Government General Hospital, Kakinada, a teaching hospital with rural referrals. OBSERVATIONS AND RESULTS: In the study cohort of 50 cases the age of patients ranged from 13 to 80 years with more number of male patients. 29 patients (58% presented with flaccid and 21 cases (42% with spastic quadriparesis. Guillian barre syndrome with 18 (36% cases was the most common cause of quadriparesis followed by Spondylotic myelopathy 11 cases ( 22% and Hypokalemic perio dic paralysis in 8 cases (16%. Transverse Myelitis. Caries spine. Secondaries cervical spine, spinal epidural abscess were in other cases.7 (14% patients had cranial nerve dysfunction. 4(8% patients had facial nerve palsy . CONCLUSION: Guillian barre syn drome constituted the most common cause of nontraumatic quadriparesis, followed by Spondylotic myelopathy, Transverse Myelitis. Caries spine. S econdaries cervical spine, spinal epidural abscess . AIDP and Hypokalemic periodic paralysis were the most frequen t causes of flaccid quadriparesis while Spondylotic myelopathy was the most common cause of spastic quadriparesis . M.R.I was the most useful and appropriate investigation . Severity of paralysis and need for ventilator support were associated with poor prog nosis in patients with acute flaccid quadriparesis . Decompressive surgery in spondylotic myelopathy had good recovery after surgery. Patient recovery was

Silent (painless) thyroiditis. Evidence of a geographic variation in frequency

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Vitug, A.C.; Goldman, J.M.

1985-03-01

Recent reports suggest that 14% to 23% of thyrotoxic patients have silent (painless) thyroiditis, a newly described syndrome characterized by transient thyrotoxicosis with a low radioactive iodine uptake. A three-year review at a Brooklyn (NY) hospital showed only one definite and three possible cases of silent thyroiditis among 86 thyrotoxic patients. At most, 4% to 5% of thyrotoxic patients had silent thyroiditis. The authors suggest a geographic variation in this syndrome. Most cases and the largest series are from Japan and the Great Lakes area of North America. The latter may be related to increased iodine intake over many years in a previously endemic area of hypoiodidism and goiter, although other local factors may also be involved.

Silent (painless) thyroiditis. Evidence of a geographic variation in frequency

International Nuclear Information System (INIS)

Vitug, A.C.; Goldman, J.M.

1985-01-01

Recent reports suggest that 14% to 23% of thyrotoxic patients have silent (painless) thyroiditis, a newly described syndrome characterized by transient thyrotoxicosis with a low radioactive iodine uptake. A three-year review at a Brooklyn (NY) hospital showed only one definite and three possible cases of silent thyroiditis among 86 thyrotoxic patients. At most, 4% to 5% of thyrotoxic patients had silent thyroiditis. The authors suggest a geographic variation in this syndrome. Most cases and the largest series are from Japan and the Great Lakes area of North America. The latter may be related to increased iodine intake over many years in a previously endemic area of hypoiodidism and goiter, although other local factors may also be involved

in a Family of South Indian Descent

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Muthiah Subramanian

2015-01-01

Full Text Available Inherited channelopathies are a heterogeneous group of disorders resulting from dysfunction of ion channels in cellular membranes. They may manifest as diseases affecting skeletal muscle contraction, the conduction system of the heart, nervous system function, and vision syndromes. We describe a family of South Indian descent with hypokalemic periodic paralysis in which four members also have idiopathic generalized epilepsy. Hypokalemic periodic paralysis is a genetically heterogeneous channelopathy that has been linked to mutations in genes encoding three ion channels CACNIAS, SCN4A, and KCNJ2 predominantly. Although data on specific gene in idiopathic generalized epilepsy is relatively scarce, mutations of voltage gated sodium channel subunit genes (CACNB4 and nonsense mutations in voltage gated calcium channels (CACNA1A have been linked to idiopathic generalized epilepsy in two families. We speculate that gene mutations altering the ability of the beta subunit to interact with the alpha subunit of the CaV1.1 channel and mutations in the pore-forming potassium channel subunit may be possible explanations for the combined manifestation of both diseases. Functional analysis of voltage gated calcium channel and other ion channels mutations may provide additional support and insight for the causal role of these mutations. The understanding of mutations in ion-channel genes will lead to improved diagnosis and treatment of such inherited channelopathies.

Periodic Paralysis and Encephalopathy as Initial Manifestations of Graves' Disease: Case Report and Review of the Literature.

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Tsironis, Theocharis; Tychalas, Athanasios; Kiourtidis, Dimitrios; Kountouras, Jannis; Xiromerisiou, Georgia; Rudolf, Jobst; Deretzi, Georgia

2017-07-01

Thyrotoxic periodic paralysis (TPP) is an uncommon complication of Graves' disease, characterized by the triad of acute hypokalemia without total body potassium deficit, episodic muscle paralysis, and thyrotoxicosis. Graves' encephalopathy is an extremely rare form of encephalopathy associated with autoimmune thyroid disease (EAATD), characterized by neuropsychiatric symptoms, increased antithyroid antibodies and cerebrospinal fluid protein concentration, nonspecific electroencephalogram abnormalities, and cortico-responsiveness. Coexistence of both these complications in the same patient has not been reported before. We herein present a 48-year-old white male patient with TPP and encephalopathy as initial presentations of Graves' disease. Flaccid tetraparesis was reversed a few hours after potassium level correction and the patient did not suffer any relapse with the successful pharmaceutical management of the thyroid function. One month later, the patient presented with dizziness and behavioral symptoms, such as inappropriate laughter and anger. Brain magnetic resonance imaging revealed meningeal enhancement and cerebrospinal fluid analysis showed a mild protein increase, with a blood-brain barrier disruption. With the suspicion of EAATD, the patient was treated with high doses of corticosteroids and improved dramatically. To our knowledge this is the first reported coexistence of potentially treatable TPP and EAATD as initial neurological manifestations of Graves' disease, thereby underscoring the necessity of suspicion of possible underlying Graves' disease in patients with acute paralysis and encephalopathy of unclear origin.

Rapid Improvement of thyroid storm-related hemodynamic collapse by aggressive anti-thyroid therapy including steroid pulse

OpenAIRE

Kiriyama, Hiroyuki; Amiya, Eisuke; Hatano, Masaru; Hosoya, Yumiko; Maki, Hisataka; Nitta, Daisuke; Saito, Akihito; Shiraishi, Yasuyuki; Minatsuki, Shun; Sato, Tatsuyuki; Murakami, Haruka; Uehara, Masae; Manaka, Katsunori; Makita, Noriko; Watanabe, Masafumi

2017-01-01

Abstract Rationale: Heart failure is relatively common in patients with hyperthyroidism, but thyrotoxic cardiomyopathy with poor left ventricular (LV) systolic function is very rare. Patient concerns: We experienced a representative case of a patient who presented with severe LV dysfunction related to thyroid storm and needed extracorporeal membrane oxygenation (ECMO) temporally. Diagnosis: Thyrotoxic cardiomyopathy. Interventions and Outcomes: Aggressive antithyroid therapy, including steroi...

Thyroid storm precipitated by radioactive iodine therapy

International Nuclear Information System (INIS)

Redkar, Neelam N.; Rawat, Kavita J.; Yelale, Abhijit; Shivchand, Akshay

2015-01-01

Thyroid storm or thyrotoxic crisis is a rare but life-threatening condition requiring immediate treatment, preferably in an intensive care unit. Its incidence is about 1-2% among patients with overt hyperthyroidism. A thyrotoxic crisis occurs predominantly in the elderly and is three to five times more common in women than in men. The overall mortality is 10-20%. Even though the pathogenesis is still not fully understood, an increased sensitivity to catecholamines appears to be an important mechanism, and a number of endogenous and exogenous stress factors that can provoke the onset of a thyrotoxic storm have been identified. Authors presented a case where the cause of precipitation of thyroid storm was improper preparation of patient for Radioactive iodine treatment

An Unusual Presenting Symptom of Graves’ Disease: Myalgia

OpenAIRE

Papanikolaou, N.; Perros, P.

2012-01-01

A 50-year-old female patient presented with severe myalgia involving her proximal muscles for 3–4 weeks. She also reported mild thyrotoxic symptoms over the same time period. Examination revealed mild thyrotoxicosis, a moderate diffuse goiter and no eye signs. The clinical picture was dominated by muscle pain and tenderness involving mainly her proximal arms and legs, her calves and her fingers, requiring opiate analgesia. Muscle power and tendon reflexes were normal. Laboratory evaluation re...

Reduced intrinsic heart rate is associated with reduced arrhythmic susceptibility in guinea-pig heart.

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Osadchii, Oleg E

2014-12-01

In the clinical setting, patients with slower resting heart rate are less prone to cardiovascular death compared with those with elevated heart rate. However, electrophysiological adaptations associated with reduced cardiac rhythm have not been thoroughly explored. In this study, relationships between intrinsic heart rate and arrhythmic susceptibility were examined by assessments of action potential duration (APD) rate adaptation and inducibility of repolarization alternans in sinoatrial node (SAN)-driven and atrioventricular (AV)-blocked guinea-pig hearts perfused with Langendorff apparatus. Electrocardiograms, epicardial monophasic action potentials, and effective refractory periods (ERP) were assessed in normokalemic and hypokalemic conditions. Slower basal heart rate in AV-blocked hearts was associated with prolonged ventricular repolarization during spontaneous beating, and with attenuated APD shortening at increased cardiac activation rates during dynamic pacing, when compared with SAN-driven hearts. During hypokalemic perfusion, the inducibility of repolarization alternans and tachyarrhythmia by rapid pacing was found to be lower in AV-blocked hearts. This difference was ascribed to prolonged ERP in the setting of reduced basal heart rate, which prevented ventricular capture at critically short pacing intervals required to induce arrhythmia. Reduced basal heart rate is associated with electrophysiological changes that prevent electrical instability upon an abrupt cardiac acceleration.

Thyrotoxicosis caused by functioning metastatic thyroid carcinoma. A rare and elusive cause of hyperthyroidism with low radioactive iodine uptake

International Nuclear Information System (INIS)

Ober, K.P.; Cowan, R.J.; Sevier, R.E.; Poole, G.J.

1987-01-01

A patient with progressively worsening thyrotoxicosis, refractory to medical therapy, is described. Repeated measurements of thyroidal RAI uptake over a 13 month period were low consistently and could not be explained by iodine ingestion, thyroiditis, or administration of exogenous thyroid hormone. An I-131 scan ultimately revealed striking activity at the base of the skull, reflecting ectopic excessive production of thyroid hormone by a solitary functioning metastatic thyroid carcinoma. The thyrotoxic state resolved after large doses of therapeutic I-131. Typical features of this rare cause of hyperthyroidism are discussed

Influência do veículo na eficácia da reposição de potássio em ratos hipocalêmicos Vehicle influence on potassium replacement effectiveness in hypokalemic rats

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Márcio Petenusso

2009-09-01

INTRODUCTION: Patients who undergo cardiac surgery are commonly treated with diuretic therapy for the management of volume overload. The concern of hypokalemia important in the adult population submitted to cardiac surgery has been described. Intravenous potassium (K+ replacement dilution is only recommended with sodium chloride 0.9% solution (SF0.9%, likely due to the putative effects of glucose solution 5% (SG5% on insulin secretion, which influence K+ replacement quality. However, it is not yet experimentally proved the influence of SF0.9% and SG5% on K+ replacement quality. Objectives: To evaluate the effects of different vehicles of K+ replacement on blood K+ levels in furosemide hypokalemic rats. METHODS: Male Wistar rats divided into four groups: K+SF, K+SG, SF and SG. Jugular vein cannulation for K+ replacement and femoral vein cannulation for blood analysis. Furosemide (50mg/kg to induce hypokalemia. We prepared the following solutions: vehicle 1.6mL (SF0.9% or SG5% + 0.4 mL de K+ (19.1% and for control groups only vehicle 2 mL. Furosemide (50 mg/kg was used to induce hypokalaemia, it was analyzed potassium plasmatic levels 24 hours before furosemide injection, 24 hours after furosemide injection and 30 minutes after post-replacement. RESULTS: There was no significative difference in blood K+ levels before furosemide administration, after hypokalemic induction and after K+ replacement among all groups. Only SF+K presented blood Na+ levels increaseafter K+ replacement (P<0.05. CONCLUSION: K+ replacement in different vehicles did not affect blood K+ levels in rats

A patient with Bartter syndrome accompanying severe growth hormone deficiency and focal segmental glomerulosclerosis.

Science.gov (United States)

Akil, Ipek; Ozen, Serkan; Kandiloglu, Ali Riza; Ersoy, Betul

2010-06-01

Bartter syndrome is a rare autosomal recessive, salt-losing disorder characterized by hypokalemic hypochloremic metabolic alkalosis. A 10-year-old boy had severe growth retardation (height standard deviation score -8.15). He had a thin, triangular face, prominent ears and forehead, and big eyes. Megacystis, bilateral hydroureteronephrosis, and residual urine were detected in ultrasonography, but there was no vesicoureteral reflux. Lumbosacral magnetic resonance (MR) showed posterior disc bulging at L4-5. Serum sodium and chloride levels were normal, but mild hypokalemia was overlooked initially. During follow-up, hypokalemic hypochloremic metabolic alkalosis developed, with high urinary chloride and potassium excretion (52 and 43 mEq/L, respectively). The patient, with renal salt loss, was thought to have classic Bartter syndrome due to absence of nephrocalcinosis, presence of persistent hypercalciuria and sensorineural deafness, and presence of relatively mild clinical and laboratory findings, except polyuria initially. The child was treated with indomethacin, spironolactone, and oral potassium in addition to growth hormone (GH). During treatment, he had considerable increase in weight and height compared with the period of GH therapy only. We present this case because, although growth retardation is a major feature of Bartter syndrome, associated GH deficiency is rarely reported in the literature. Diagnosis of Bartter syndrome was made later, as our patient was followed for megacystis and megaureter secondary to the neurogenic bladder and GH deficiency initially; and proteinuria associated with focal segmental glomerulosclerosis responded to treatment for Bartter syndrome.

Determinants of Thyrotoxic Cardiomyopathy Recovery

Directory of Open Access Journals (Sweden)

Lucia Oliveros-Ruiz

2013-01-01

Full Text Available The purpose was to evaluate the effect of the disease duration prior to treatment, thyroid hormones level, or both on the reversibility of dilated cardiomyopathy. Between January 2006 and December 2010, a longitudinal study with a 6 months follow-up was carried on. One hundred and seventy patients with hyperthyroidism were referred to the cardiologist, and 127 had a 6 months followup after antithyroid treatment and were evaluated by echocardiography. Dilated cardiomyopathy reversibility criteria were established according to echocardiographic parameters. Complete reversibility existed when all parameters were met, partial reversibility when LVEF was ≥55% plus two or three other parameters, and no reversibility when LVEF was ≤55% regardless of other parameters. The results showed that echocardiography parameters related to the regression of myocardial mass were associated with a disease duration shorter than 10.38 months. This was the main predictive variable for reversal of dilated cardiomyopathy, followed by β-blocker treatment, and the last predictive variable was the serum level of free triiodothyronine. This study showed that the effect on the myocardium related to thyrotoxicosis was associated with the disease duration before treatment.

First results with a radioreceptor-assay (TRAK-Assay) for TSH-receptor-autoantibodies

International Nuclear Information System (INIS)

Becker, W.; Reiners, C.; Boerner, W.

1983-01-01

A new radioreceptor-assay (TRAK-assay) for autoantibodies against TSH-receptors was tested in 48 untreated thyrotoxic patients (26 regional autonomies, 22 toxic diffuse goiters). None of the 26 patients with regional autonomy showed positive autoantibody-titers. 4 patients with toxic diffuse goiter and thyrotoxic exophthalmos were TRAK-positive. Positive titers of microsomal and thyreoglobulin autoantibodies could be seen in 8 of 9 patients with positive TRAK-titers. In accordance with the conventional methods for detecting thyroid-stimulating immunoglobulins the new TRAK-assay seems to be suited for differentiating between immunogenic toxic diffuse goiter (Graves' disease) and goiter with disseminated autonomy as well as for prediction of relapse. (orig.) [de

Radioimmunoassay of Plasma Insulin during Oral Glucose Tolerance Test in Thyrotoxicosis

Energy Technology Data Exchange (ETDEWEB)

Lee, Hong Kyu; Koh, Chang Soon; Lee, Mun Ho [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1971-03-15

Blood glucose and immunoreactive insulin (IRI) were measured during oral glucose tolerance test in 15 thyrotoxic patients and 8 normal controls, to study the glucose metabolism in thyrotoxicosis. Following were the results;1) In thyrotoxicosis, there is noticed late rise and late fall of plasma IRI during oral glucose tolerance test, like as phenomenon of mild diabetes mellitus. 2) When the thyrotoxic patients were divided into normal and abnormal responsive groups after the level of blood glucose by Wilkerson Criteria, no significant difference in plasma IRI levels were noticed between two groups. 3) This result may be interpreted as relative deficiency of insulin secretion from panaceas and suggest genetically related defects.

Adult presentation of Bartter syndrome type IV with erythrocytosis.

Science.gov (United States)

Heilberg, Ita Pfeferman; Tótoli, Cláudia; Calado, Joaquim Tomaz

2015-01-01

Bartter syndrome comprises a group of rare autosomal-recessive salt-losing disorders with distinct phenotypes, but one unifying pathophysiology consisting of severe reductions of sodium reabsorption caused by mutations in five genes expressed in the thick ascending limb of Henle, coupled with increased urinary excretion of potassium and hydrogen, which leads to hypokalemic alkalosis. Bartter syndrome type IV, caused by loss-of-function mutations in barttin, a subunit of chloride channel CLC-Kb expressed in the kidney and inner ear, usually occurs in the antenatal-neonatal period. We report an unusual case of late onset presentation of Bartter syndrome IV and mild phenotype in a 20 years-old man who had hypokalemia, deafness, secondary hyperparathyroidism and erythrocytosis.

Generaliserede kramper som debutsymptom ved Gitelmans syndrom

DEFF Research Database (Denmark)

Hvelplund, Carolina; Jeppesen, Eva Mosfeldt; Mortensen, Henrik B

2009-01-01

Gitelman's syndrome is a rare autosomal recessive syndrome presenting with hypocalciuria, hypomagnesiemia and hypokalemic metabolic alkalosis. This case reports a patient admitted with generalized seizures with the above-mentioned biochemical abnormalities, thus representing a rare onset of Gitel...

Anti-arrhythmic peptide N-3-(4-hydroxyphenyl)propionyl Pro-Hyp-Gly-Ala-Gly-OH reduces dispersion of action potential duration during ischemia/reperfusion in rabbit hearts

DEFF Research Database (Denmark)

Kjølbye, Anne Louise; Petersen, Jørgen Søberg; Holstein-Rathlou, N.-H.

2002-01-01

During ischemia, cardiac gap junctions close and neighboring cells uncouple. This leads to slow conduction, increased dispersion of APD90 (duration from action potential beginning to 90% of repolarization), nonuniform anisotropy, and unidirectional conduction block, all of which favor the induction...... of reentry arrhythmias. It has been suggested that anti-arrhythmic peptides increase gap junction conductance during states of reduced coupling. The aim of this study was to test the effect of the anti-arrhythmic peptide N-3-(4-hydroxyphenyl)propionyl Pro-Hyp-Gly-Ala-Gly-OH (HP-5) (10(-10) ) on dispersion...... of epicardial APD90 during both normokalemic and hypokalemic ischemia/reperfusion in isolated perfused rabbit hearts. HP-5 did not affect average APD90, heart rate, left ventricular contractility (LVP dP/dtmax), or mean coronary flow. HP-5 significantly reduced the epicardial APD dispersion during hypokalemic...

[Diagnosis and treatment of thyroid storm].

Science.gov (United States)

Akamizu, Takashi

2012-11-01

Thyrotoxic storm is a life-threatening condition requiring emergency treatment. Neither its epidemiological data nor diagnostic criteria have been fully established. We clarified the clinical and epidemiological characteristics of thyroid storm using nationwide surveys and then formulate diagnostic criteria for thyroid storm. To perform the nationwide survey on thyroid storm, we first developed tentative diagnostic criteria for thyroid storm, mainly based upon the literature (the first edition). We analyzed the relationship of the major features of thyroid storm to mortality and to certain other features. Finally, based upon the findings of these surveys, we revised the diagnostic criteria. Thyrotoxic storm is still a life-threatening disorder with over 10% mortality in Japan.

Gitelman syndrome.

NARCIS (Netherlands)

Knoers, N.V.A.M.; Levtchenko, E.N.

2008-01-01

Gitelman syndrome (GS), also referred to as familial hypokalemia-hypomagnesemia, is characterized by hypokalemic metabolic alkalosis in combination with significant hypomagnesemia and low urinary calcium excretion. The prevalence is estimated at approximately 1:40,000 and accordingly, the prevalence

Hyperthyroidism

Science.gov (United States)

... calcium supplement. Thyrotoxic crisis. A sudden worsening of hyperthyroidism symptoms that leads to a fever, rapidpulse, and delirium. Signs of delirium include decreased awareness, confusion, and restlessness. ...

Clinical course and treatment response in patients with thyroid hot nodule

International Nuclear Information System (INIS)

Fard Esfahani, A; Aghayousefi, H.R.; Eftekhari, M.; Fallahi, B.; Saghari, M.

2002-01-01

This is a retrospective study on clinical course and treatment response of patients with thyroid hot nodule, referred to nuclear medicine department of shariaty hospital from 1360 to 1377. From the total 58 patients with average age of 43 year and incidence peak of 40 year, 81 % were female and 19 % were male. 64 % of the patients were thyrotoxic and 36 % were euthyroid at presentation. Thyrotoxic symptoms and signs increased with age (p= 0.04). 57% of patients received I-131 therapy without premedication. 7% received antithyroid drugs first and then underwent iodine therapy. From 36% of the patients who were euthyroid at presentation, 15.5 % became thyrotoxic on follow up studies and received I-131 therapy, but 20.7 % remained euthyroid without receiving andy therapy. The average of first and cumulative radioiodine doses were 16.9 mci and 21.8 mci, respectively. Treatment response during 6 and 12 month follow up were 80 % and 86.7 %, respectively. The more administered the first dose, the better was the response (p= 0.03). Men appeared to need more I-131 dosage and times of therapy as compared to women. Post radioiodine hypothyroidism incidence was 7.5 % during one year follow up. No meaningful relation was found between times of radioiodine therapy and thyroid or nodule size

Gitelman syndrome : consensus and guidance from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

NARCIS (Netherlands)

Blanchard, Anne; Bockenhauer, Detlef; Bolignano, Davide; Calò, Lorenzo A; Cosyns, Etienne; Devuyst, Olivier; Ellison, David H; Karet Frankl, Fiona E; Knoers, Nine V A M; Konrad, Martin; Lin, Shih-Hua; Vargas-Poussou, Rosa

Gitelman syndrome (GS) is a rare, salt-losing tubulopathy characterized by hypokalemic metabolic alkalosis with hypomagnesemia and hypocalciuria. The disease is recessively inherited, caused by inactivating mutations in the SLC12A3 gene that encodes the thiazide-sensitive sodium-chloride

Clinical outcome during the peri-operative (thyroidectomy) period of severely hyperthyroid patients with normalized pre-operative free-T4 levels: Importance of I-131 therapy as a part of pre-operative preparation

International Nuclear Information System (INIS)

Siguan-Crisaldo, M.A.L.; Mercado-Asis, L.B.

2005-01-01

Thyroidectomy is performed for hyperthyroidism on patients who do not respond to or are not compliant with medical therapy and in patients with very large goiters causing compressive symptoms. All thyrotoxic patients undergoing thyroidectomy usually are first treated with anti-thyroid drugs to normalize free thyroid hormone levels and render them euthyroid before surgery in order to prevent complications particularly thyroid storm and circulatory collapse. In this case series, we describe the clinical outcome during the perioperative (thyroidectomy) period of three severely hyperthyroid patients, two females and one male, with ages ranging from 13 to 38 years. All patients had grade III goiter, and only one had exophthalmos. The mean duration of goiter was 3.6 years. All of them were given preoperative treatment consisting of propylthiouracil (PTU) at 450-600 mg/day; iodone, 3 tablets daily and propranolol at 30-120 mg/day for one month. All of them had normalized preoperative thyroid function tests. In addition to the preoperative medications mentioned above, all three patients received radioactive iodine therapy before surgery. The first two patients received relatively low doses of 8.0 and 7.5 mCi of I-131 respectively. Unfortunately the first patient had supraventricular tachycardia (SVT), post skin cutting and the other one went into thyroid storm. The third patient who received a cumulative dose of 23.5 mCi of I-131 before surgery had an uneventful postoperative course. It is concluded that normalization of thyroid hormone parameters, especially free T4 is not sufficient for an uneventful and uncomplicated peri-thyroidectomy period in severely hyperthyroid patients with large goiters. Effective radioactive iodine therapy might prove to be helpful in inducing thyroid tissue fibrosis, thus leading to true clinical euthyroidism and excellent clinical course postoperatively. (author)

Efficacy of protocols for induction of chronic hyperthyroidism in male and female mice.

Science.gov (United States)

Engels, Kathrin; Rakov, Helena; Zwanziger, Denise; Hönes, Georg Sebastian; Rehders, Maren; Brix, Klaudia; Köhrle, Josef; Möller, Lars Christian; Führer, Dagmar

2016-10-01

Protocols for induction of hyperthyroidism in mice are highly variable and mostly involve short-term thyroid hormone (TH) treatment. In addition, little is known about a possible influence of sex on experimental TH manipulation. Here we analyzed the efficacy of intraperitoneal vs. oral levothyroxine (T4) administration to induce chronic hyperthyroidism in male and female mice and asked which T4 dosing intervals are required to achieve stable organ thyrotoxicosis. T4 was administered intraperitoneally or orally over a period of 6/7 weeks. Assessment included monitoring of body weight, TH serum concentrations, and serial quantitative TH target gene expression analysis in liver and heart. Our results show that both intraperitoneal and oral T4 treatment are reliable methods for induction of chronic hyperthyroidism in mice. Thereby T4 injection intervals should not exceed 48 h and oral levothyroxine should be administered continuously during experiments and up to sacrifice to ensure a hyperthyroid organ state. Furthermore, we found a sex-dependent variation in levothyroxine-induced TH serum state, with significantly higher T4 concentrations in female mice, while expression of investigated classical TH responsive genes in liver and heart did not vary with animal's sex. In summary, our study shows that common approaches for rendering rodents thyrotoxic can also be used for induction of chronic hyperthyroidism in male and female mice. Thereby T4 dosing intervals are critical as are read-out parameters to verify a chronic thyrotoxic organ state.

Outcome of surgery for toxic goitres in maiduguri: A single teaching ...

African Journals Online (AJOL)

2011-08-28

Aug 28, 2011 ... preoperative assessment, postoperative complications, and histopathological reports ... effort to remove more gland to reduce the incidence of recurrent ... anxiety, heat intolerance, and 42 (53.8%) had thyrotoxic eye symptom.

Flaccid quadriplegia due to thyrotoxic myopathy.

Science.gov (United States)

Couillard, Philippe; Wijdicks, Eelco F M

2014-04-01

Acute flaccid paralysis is an important clinical problem in neurological critical care. After implementing life-supporting measures, it is imperative to identify the correct diagnosis to provide timely appropriate care. Thyrotoxicosis is a recognized cause of myopathy, but rarely of quadriplegia. Here, we report a case of hyperthyroidism with severe weakness. Case report and video demonstration of clinical examination. We describe a case of a 59-year-old woman with Grave's disease who presented to the hospital with progressive shortness of breath secondary to atrial fibrillation with rapid ventricular response. Following contrast administration, she had a pulseless electrical activity arrest from which she recovered without cognitive sequelae, but with flaccid quadriplegia, facial diplegia, and hypophonia. CK was mildly elevated and electrolytes were essentially normal. Nerve conduction studies and electromyography demonstrated features supporting an acute myopathy without evidence of neuromuscular junction conduction abnormality. Normalization of thyroid hormones resulted in slow, but steady improvement over months after which she regained ambulation. Acute flaccid quadriplegia can result from thyrotoxicosis. With normalization of thyroid function, recovery can be expected.

Case report: Basedow paraplegia: A possible misnomer | Smith ...

African Journals Online (AJOL)

Thyrotoxic myopathy frequently occurs in clinical practice; however, the association of hyperthyroidism with a flaccid, areflexic paraplegia, so-called ... It is important to consider and treat other causes, such as acute idiopathic polyneuritis.

Basedow paraplegia: A possible misnomer

African Journals Online (AJOL)

Thyrotoxic myopathy frequently occurs in clinical practice; however, the ... The occurrence of hyperthyroidism with a flaccid, areflexic paraplegia appears ... It is important to consider and treat other causes, such as acute idiopathic polyneuritis.

Persistent severe hypokalemia: Gitelman syndrome and differential diagnosis

Directory of Open Access Journals (Sweden)

Christine Zomer Dal Molin

Full Text Available Abstract The main causes of hypokalemia are usually evident in the clinical history of patients, with previous episodes of vomiting, diarrhea or diuretic use. However, in some patients the cause of hypokalemia can become a challenge. In such cases, two major components of the investigation must be performed: assessment of urinary excretion potassium and the acid-base status. This article presents a case report of a patient with severe persistent hypokalemia, complementary laboratory tests indicated that's it was hypomagnesaemia and hypocalciuria associated with metabolic alkalosis, and increase of thyroid hormones. Thyrotoxic periodic paralysis was included in the differential diagnosis, but evolved into euthyroid state, persisting with severe hypokalemia, which led to be diagnosed as Gitelman syndrome.

Evolution of periodicity in periodical cicadas.

Science.gov (United States)

Ito, Hiromu; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Koyama, Takuya; Sota, Teiji; Cooley, John R; Yoshimura, Jin

2015-09-14

Periodical cicadas (Magicicada spp.) in the USA are famous for their unique prime-numbered life cycles of 13 and 17 years and their nearly perfectly synchronized mass emergences. Because almost all known species of cicada are non-periodical, periodicity is assumed to be a derived state. A leading hypothesis for the evolution of periodicity in Magicicada implicates the decline in average temperature during glacial periods. During the evolution of periodicity, the determinant of maturation in ancestral cicadas is hypothesized to have switched from size dependence to time (period) dependence. The selection for the prime-numbered cycles should have taken place only after the fixation of periodicity. Here, we build an individual-based model of cicadas under conditions of climatic cooling to explore the fixation of periodicity. In our model, under cold environments, extremely long juvenile stages lead to extremely low adult densities, limiting mating opportunities and favouring the evolution of synchronized emergence. Our results indicate that these changes, which were triggered by glacial cooling, could have led to the fixation of periodicity in the non-periodical ancestors.

Metastatic papillary carcinoma of the thyroid in a patient previously ...

African Journals Online (AJOL)

Keywords: Graves' disease, papillary thyroid carcinoma, radioactive iodine. Résumé. Accessoire de ... une cause de préoccupation et de controverse pour ceux qui s'occupent d'eux. ... remained thyrotoxic warranting administration of three ...

Thyroid carcinoma and hyperthyroidism in a dog

OpenAIRE

Bezzola, Pauli

2002-01-01

A 10-year old spayed, female Labrador retriever, with an 8-month history of weight loss, increased heart rate, and hyperactivity, was diagnosed with hyperthyroidism and a thyroid neoplasm. Thyrotoxic heart disease is documented in this case.

Evaluation of thyroid function tests in non-thyroidal illness

International Nuclear Information System (INIS)

Schutte, D.P.

1988-01-01

Normal thyroid physiology and pathophysiology with reference to non-thyroidal illness (NTI) is reviewed including specific disease states and drugs and their effect on thyroid function tests. The diagnostic utility of two new highly sensitive thyrotrophin (TSH) assays as screening tests for thyroid dysfunction are evaluated and compared with conventional thyroid function assays. A group of 40 patients with NTI was studied. This group was compared to a group of normal controls and a group of thyrotoxic patients. Conventional thyroid function tests yielded many values outside the reference range in the NTI group. The general pattern that emerged was decreased total triiodothyronine levels in 70% of NTI patients, normal to low thyroxine values, increased mean free thyroxine values (dialysis), low mean values for the free thyroxine index and varying results for newer commercial assays for free thyroxine according to methodology. The TSH response to intravenous thyroliberin (TRH) was found to be blunted compared to controls. Basal TSH levels were measured with two ultasensitive TSH assays. The immunoradiometric assays yielded fewer values outside the reference range in the NTI group than conventional thyroid function tests. This assay yielded undetectable basal TSH levels in all thyrotoxic patients and could reliably separate thyrotoxic patients from the NTI group. Basal TSH levels with ultrasensitive TSH assays correlated well with the TSH response to TRH (TSH) and could obviate the need for TRH tests. Ultrasensitive TSH assays are promising first line screening tests in NTI. 120 refs., 13 figs., 7 tabs

Radioiodine-induced thyroid storm. Case report and literature review

Energy Technology Data Exchange (ETDEWEB)

McDermott, M.T.; Kidd, G.S.; Dodson, L.E. Jr.; Hofeldt, F.D.

1983-08-01

Thyroid storm developed following radioiodine therapy in a 43-year-old man with Graves' disease, weight loss, myopathy, severe thyrotoxic hypercalcemia, and a pituitary adenoma. The hypercalcemia may have been a significant, and previously unreported, predisposing factor for the radioiodine-associated thyroid storm. This case and 15 other well-documented cases of radioiodine-associated storm found in the literature are reviewed, as are several other cases of less severe exacerbations of thyrotoxicosis associated with radioiodine therapy. Although not often seen, these complications are often fatal. High-risk patients, such as the elderly, those with severe thyrotoxicosis, and those with significant underlying diseases, may benefit from preventive measures such as the judicious use of thyrostatic medications during the periods before and after isotope administration.

Radioiodine-induced thyroid storm. Case report and literature review

International Nuclear Information System (INIS)

McDermott, M.T.; Kidd, G.S.; Dodson, L.E. Jr.; Hofeldt, F.D.

1983-01-01

Thyroid storm developed following radioiodine therapy in a 43-year-old man with Graves' disease, weight loss, myopathy, severe thyrotoxic hypercalcemia, and a pituitary adenoma. The hypercalcemia may have been a significant, and previously unreported, predisposing factor for the radioiodine-associated thyroid storm. This case and 15 other well-documented cases of radioiodine-associated storm found in the literature are reviewed, as are several other cases of less severe exacerbations of thyrotoxicosis associated with radioiodine therapy. Although not often seen, these complications are often fatal. High-risk patients, such as the elderly, those with severe thyrotoxicosis, and those with significant underlying diseases, may benefit from preventive measures such as the judicious use of thyrostatic medications during the periods before and after isotope administration

Co-Existence of Tuberous Sclerosis and the Fanconi Syndrome in Two Saudi Male Siblings: Report on Two Cases

International Nuclear Information System (INIS)

Al-Hwiesh, Abdulla K.; Al-Mueilo, Samir H.; Saeed, Ibrahim; Barak, Infal H.; Al-Muhanna, Fahd A.

2005-01-01

In this report, we present two cases of familial tuberous sclerosis co-existing with the Fanconi Syndrome. Both cases presented with history of failure to thrive and mental retardation associated with hypokalemic metabolic acidosis. To our knowledge, the association between tuberous sclerosis and the Fanconi Syndrome has not been reported previously. (author)

[Pseudo-Bartter syndrome--2 cases].

Science.gov (United States)

Jóźwiak, Lucyna; Jaroszyński, Andrzej; Baranowicz-Gaszczyk, Iwona; Borowicz, Ewa; Ksiazek, Andrzej

2010-01-01

Bartter syndrome represents the group of renal disturbances characterized by hypokaliemia and metabolic alkalosis. Some diseases could display hypokalemic metabolic alkalosis without primary tubular dysfunction. These disorders are called pseudo-Bartter syndrome. In this paper we present 2 cases of pseudo-Bartter syndrome related among to other things to overuse of diuretic drugs.

Parálisis periódica hipocalémica familiar (PPHF: reporte de un caso y revisión del tema Periodic familial hypoaklemic paralysis: report of a case and review of the literature

Directory of Open Access Journals (Sweden)

José William Cornejo Ochoa

2002-02-01

Full Text Available La parálisis periódica hipocalémica familiar es una enfermedad que pertenece al grupo de las canalopatías. Consiste en la presentación de episodios de parálisis muscular progresivos en intensidad y frecuencia acompañada de hipocalemia. dos mutaciones explican la presencia de la enfermedad, la CACNA1S y la SCN4A, que afectan los canales de potasio mediados por calcio y los canales de sodio, respectivamente. Lo anterior repercute en la función de los canales para el potasio mediados por voltaje, llevando a una hipocalemia extracelular sostenida produciendo despolarización continua con parálisis. Los desencadenantes son el ejercicio, los carbohidratos, el frío, el estrés, entre otros, y las pruebas de provocación clínica se realizan con insulina, glucosa y ejercicio. La enfermedad se puede prevenir evitando estos factores y tiene alguna respuesta al tratamiento con acetazolamida. Se presenta el caso clínico de un niño que cumple con los criterios clínicos de paresia asociada a hipocalemia desencadenada por carbohidratos. Periodic hypokalemic familial paralysis (PHFP is a channel-mediated disease. Increasing focal or generalized muscular paralytic episodes are associated with low serum potassium levels. Two point mutations are described, CACNA1S and SCN4A. These mutations affect calcium and sodium mediated potassium channels. A continuous depolarization with low extracelular potassium promotes hypotonia. Known stressors are excercise, cold, stress and high carbohydrate intake. Control of stressors and azetazolamyde are the main treatment options. We describe one patient with clinical and laboratory characteristics of PHFP.

Bartter's syndrome: A case report of nephrocalcinosis

OpenAIRE

KOŞAN, Celalettin

2014-01-01

Bartter's syndrome is characterized by generalized hyperplasia of juxtaglomerular apparatus, hyperreninism leading to secondary hyperaldesteronism, hypokalemic alkalosis and normal blood pressure. Although nephrocalcinosis has been described sporadically in patients with Barter's syndrome, this is still generally unrecognized. We reported a case of Barter's syndrome with nephrocalcinosis and discussed clinical significance of nephrocalcinosis in this syndrome.

Gitelman syndrome combined with complete growth hormone deficiency

Directory of Open Access Journals (Sweden)

Se Ra Min

2013-03-01

Full Text Available Gitelman syndrome is a rare autosomal recessive hereditary salt-losing tubulopathy, that manifests as hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria. It is caused by mutations in the solute carrier family 12(sodium/chloride transporters, member 3 (SLC12A3 gene encoding the thiazide-sensitive sodium chloride cotransporter channel (NCCT in the distal convoluted tubule of the kidney. It is associated with muscle weakness, cramps, tetany, vomiting, diarrhea, abdominal pain, and growth retardation. The incidence of growth retardation, the exact cause of which is unknown, is lower than that of Bartter syndrome. Herein, we discuss the case of an overweight 12.9-year-old girl of short stature presenting with hypokalemic metabolic alkalosis. The patient, on the basis of detection of a heterozygous mutation in the SLC12A3 gene and poor growth hormone (GH responses in two provocative tests, was diagnosed with Gitelman syndrome combined with complete GH deficiency. GH treatment accompanied by magnesium oxide and potassium replacement was associated with a good clinical response.

Use of beta-adrenoceptor blocking drugs in hyperthyroidism.

Science.gov (United States)

Feely, J; Peden, N

1984-05-01

There is an increasing use and variety of beta-adrenoceptor blocking agents (beta-blockers) available for the treatment of hyperthyroidism. Recent comparative studies suggest that atenolol (200mg daily), metoprolol (200mg daily); acebutolol (400mg daily), oxprenolol ( 160mg daily), nadolol ( 80mg daily) and timolol (20mg daily) produce a beneficial clinical response equal to that seen with propranolol ( 160mg daily). Most beta-blockers reduce resting heart rate by approximately 25 to 30 beats/min, although a lesser reduction is seen with those possessing intrinsic sympathomimetic activity such as oxprenolol and pindolol. While earlier studies employing large doses of intravenous propranolol concluded that beta-blockade reduced myocardial contractility, more recent non-invasive studies suggest that the predominant cardiac effect is on heart rate. In patients with cardiac failure, beta-blockers may, however, produce a profound fall in cardiac output. Nevertheless, in combination with digoxin they may be useful in controlling the atrial fibrillation of thyrocardiac disease. beta-Blockers improve nervousness and tremor (although to a lesser extent with cardioselective agents) and severe myopathy, and they also reduce the frequency of paralysis in patients with thyrotoxic periodic paralysis. There is often subjective improvement in sweating but usually no major effect on eye signs. Recent studies show a 10% reduction in oxygen consumption/basal metabolic rate with long term oral use of selective or nonselective beta-blockers. In addition, many agents (propranolol, metoprolol, nadolol and sotalol but not acebutolol, atenolol or oxprenolol) reduce circulating tri-iodothyronine (T3) concentration by between 10 and 40%, although the clinical significance of this effect (if any) is not established. beta-Blockers may also have endocrinological effects on gastrin, cyclic AMP, catecholamines and other hormone levels. Given in adequate dosage, propranolol has been shown to

Experience in the use of radioactive iodine therapy for ...

African Journals Online (AJOL)

The age range was 31 to 60 years, with a mean age of 44.2 ± 1.8 years. ... thyrotoxic heart disease, recurrent thyrotoxicosis and failed antithyroid drug therapy. ... patients, but a high rate of default precludes adequate long-term follow-up.

Chronic mesenteric volvulus in a dog

Science.gov (United States)

Spevakow, Andrea B.; Nibblett, Belle Marie D.; Carr, Anthony P.; Linn, Kathleen A.

2010-01-01

A chronic, partial mesenteric volvulus was found on laparotomy of an adult Bernese mountain dog with a 4-month history of intermittent vomiting, diarrhea, and weight loss. The dog had elevated cholestatic and hepatocellular leakage enzymes, increased bile acids, azotemia, isosthenuria, and a hypokalemic, hypochloremic, metabolic alkalosis. The dog recovered fully following reduction of the volvulus. PMID:20357947

Peri-operative concerns in a patient with thyroid storm secondary to molar pregnancy

Directory of Open Access Journals (Sweden)

Tanvir Samra

2015-01-01

Full Text Available Awareness of the presence of thyroid function abnormalities in patients with molar pregnancy is important for its prompt diagnosis and management. We report the development of thyroid storm in the immediate post-operative period in a 25-year-old female who underwent evacuation of her molar pregnancy under saddle spinal block after being controlled for her thyrotoxicosis with a combination of antithyroid drugs, iodine, steroids and adrenergic blocking agents. We advocate the use of esmolol infusions up to a maximum dose of 200 μg/kg/min for immediate haemodynamic management of the patient. Optimum time needed for stabilisation of the hyper metabolic state after initiation of antithyroid drugs is still not known and evacuation of molar pregnancy remains the only definitive management of the thyrotoxic state.

Thyroid diseases and cerebrovascular disease

NARCIS (Netherlands)

Squizzato, A.; Gerdes, V. E. A.; Brandjes, D. P. M.; Büller, H. R.; Stam, J.

2005-01-01

Background and Purpose-Acute cerebral ischemia has been described in different diseases of the thyroid gland, and not only as a result of thyrotoxic atrial fibrillation and cardioembolic stroke. The purpose of this review is to summarize the studies on the relationship between thyroid diseases and

Fatal thyrocardiac event

Directory of Open Access Journals (Sweden)

Samit Kumar Khutia

2010-01-01

Full Text Available Atrial fibrillation occurs frequently (2-20% in chronic hyperthyroidism patients. Poorly treated thyrotoxic patients may present with a life-threatening cerebrovascular accident giving little scope to revert the situation. At times, it is difficult to make a patient euthyroid with conventional management. The definitive treatment of choice is 131 I, radioiodine. An adjusted dose of an oral anticoagulant is highly efficacious for the prevention of all types of strokes. Timely intervention by a skilled airway manager with right instruments is the key to success in airway management. A 50-year-old thyrotoxic, semiconscious male presented with a sudden onset of haemiplegia. He had chronic AF, a huge thyroid swelling with gross tracheal deviation and dilated cardiomyopathy. A CT scan showed infarction in the left middle cerebral artery territory. After initial improvement with conservative management, patient′s condition deteriorated in the next 48 h. Repeat CT scan showed increase in the infarct size with haemorrhage and midline shift. Finally, he died despite all resuscitative measures.

Atrial fibrillation and hyperthyroidism: A literature review.

Science.gov (United States)

Reddy, Vivek; Taha, Wael; Kundumadam, Shanker; Khan, Mazhar

Atrial fibrillation is the most common arrhythmia worldwide with increasing frequency noted with age. Hyperthyroidism is a well-known cause of atrial fibrillation with a 16%-60% prevalence of atrial fibrillation in patients with known hyperthyroidism Ross et al. (2016). While hyperthyroidism as a causative factor of atrial fibrillation is well established, this literature review aims to answer several questions on this topic including: 1. The relationship of atrial fibrillation to hyperthyroidism 2. Atrial fibrillation as a predictor of hyperthyroidism 3. The pathophysiology of thyrotoxic atrial fibrillation 4. Subclinical hyperthyroidism and the relationship with atrial fibrillation 5. Cardioversion and Catheter ablation of hyperthyroid patients with atrial fibrillation 6. Thrombotic risk of hyperthyroid patients with atrial fibrillation 7. Management of Thyrotoxic Atrial fibrillation 8. Pharmacological rhythm control in patients with hyperthyroidism and atrial fibrillation 9. Treatment of Hyperthyroidism to prevent atrial fibrillation 10. Clinical Implications of Hyperthyroidism and Atrial Fibrillation. Copyright © 2017 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Development of Hyperthyroidism Following Primary Hypothyroidism: A Case Report

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Yueh-Hua Chung

2004-04-01

Full Text Available Development of hyperthyroidism following primary hypothyroidism is uncommon, and only a few documented cases have been reported. Alterations in thyroid-stimulating hormone receptor antibodies in serum are currently considered to play the main role in the pathophysiology, but the exact mechanism is still unknown. Here, we report the case of a 60-year-old man with disturbed consciousness due to hyponatremia. Thyroid function tests showed primary hypothyroidism with a high anti-microsomal antibody titer (1:6,400. The patient experienced weight loss and exophthalmos 6 years later. Serum thyroid hormone levels were increased and thyroxine treatment was discontinued, but the patient remained thyrotoxic 2 months later. 131I thyroid uptake was 40.9% at 24 hours, and bilateral thyroid lobes were not enlarged with diffuse radioactivity. Six months later, the patient was still thyrotoxic and therapy with methimazole 10 mg/day was started. He is now taking methimazole and is euthyroid.

Muscle channelopathies and electrophysiological approach

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Cherian Ajith

2008-01-01

Full Text Available Myotonic syndromes and periodic paralyses are rare disorders of skeletal muscle characterized mainly by muscle stiffness or episodic attacks of weakness. Familial forms are caused by mutation in genes coding for skeletal muscle voltage ionic channels. Familial periodic paralysis and nondystrophic myotonias are disorders of skeletal muscle excitability caused by mutations in genes coding for voltage-gated ion channels. These diseases are characterized by episodic failure of motor activity due to muscle weakness (paralysis or stiffness (myotonia. Clinical studies have identified two forms of periodic paralyses: hypokalemic periodic paralysis (hypoKPP and hyperkalemic periodic paralysis (hyperKPP, based on changes in serum potassium levels during the attacks, and three distinct forms of myotonias: paramyotonia congenita (PC, potassium-aggravated myotonia (PAM, and myotonia congenita (MC. PC and PAM have been linked to missense mutations in the SCN4A gene, which encodes α subunit of the voltage-gated sodium channel, whereas MC is caused by mutations in the chloride channel gene (CLCN1. Exercise is known to trigger, aggravate, or relieve symptoms. Therefore, exercise can be used as a functional test in electromyography to improve the diagnosis of these muscle disorders. Abnormal changes in the compound muscle action potential can be disclosed using different exercise tests. Five electromyographic (EMG patterns (I-V that may be used in clinical practice as guides for molecular diagnosis are discussed.

A patient with Dent disease and features of Bartter syndrome caused by a novel mutation of CLCN5.

Science.gov (United States)

Okamoto, Takayuki; Tajima, Toshihiro; Hirayama, Tomoya; Sasaki, Satoshi

2012-02-01

Dent disease is an X-linked tubulopathy mainly caused by inactivating mutations of CLCN5. Features of Bartter syndrome such as hypokalemic metabolic alkalosis are rarely observed in patients with Dent disease. We report a Japanese male patient with Dent disease who also manifested features of Bartter syndrome. At the age of 3 years, he was diagnosed with Dent disease based on low molecular weight proteinuria and hypercalciuria. One year later, he was found to have features of Bartter syndrome, i.e., hypokalemia and metabolic alkalosis, and high levels of plasma renin activity and aldosterone with a normal blood pressure. Despite medical interventions, he developed chronic kidney disease stage 3 at the age of 21 years. To investigate the molecular basis of his disease, CLCN5, KCNJ1, SLC12A1, and CLCkb were analyzed and a novel mutation (Y567X) in CLCN5 was identified. Hypokalemic metabolic alkalosis is a rare manifestation in Dent disease. It is speculated that Dent patients with features of Bartter syndrome are susceptible to progression to renal failure. To study this hypothesis, additional observations and long-term follow-up of such patients are necessary.

Periodic feedback stabilization for linear periodic evolution equations

CERN Document Server

Wang, Gengsheng

2016-01-01

This book introduces a number of recent advances regarding periodic feedback stabilization for linear and time periodic evolution equations. First, it presents selected connections between linear quadratic optimal control theory and feedback stabilization theory for linear periodic evolution equations. Secondly, it identifies several criteria for the periodic feedback stabilization from the perspective of geometry, algebra and analyses respectively. Next, it describes several ways to design periodic feedback laws. Lastly, the book introduces readers to key methods for designing the control machines. Given its coverage and scope, it offers a helpful guide for graduate students and researchers in the areas of control theory and applied mathematics.

Life-Threatening Hypokalemic Paralysis in a Young Bodybuilder

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Kitty K. T. Cheung

2014-01-01

Full Text Available We report a case of life-threatening hypokalemia in a 28-year-old bodybuilder who presented with sudden onset bilateral lower limbs paralysis few days after his bodybuilding competition. His electrocardiogram (ECG showed typical u-waves due to severe hypokalemia (serum potassium 1.6 mmol/L, reference range (RR 3.5–5.0 mmol/L. He was admitted to the intensive care unit (ICU and was treated with potassium replacement. The patient later admitted that he had exposed himself to weight loss agents of unknown nature, purchased online, and large carbohydrate loads in preparation for the competition. He made a full recovery after a few days and discharged himself from the hospital against medical advice. The severe hypokalemia was thought to be caused by several mechanisms to be discussed in this report. With the ever rising number of new fitness centers recently, the ease of online purchasing of almost any drug, and the increasing numbers of youngsters getting into the bodybuilding arena, clinicians should be able to recognize the possible causes of sudden severe hypokalemia in these patients in order to revert the pathophysiology.

Life-threatening hypokalemic paralysis in a young bodybuilder.

Science.gov (United States)

Cheung, Kitty K T; So, Wing-Yee; Kong, Alice P S; Ma, Ronald C W; Chow, Francis C C

2014-01-01

We report a case of life-threatening hypokalemia in a 28-year-old bodybuilder who presented with sudden onset bilateral lower limbs paralysis few days after his bodybuilding competition. His electrocardiogram (ECG) showed typical u-waves due to severe hypokalemia (serum potassium 1.6 mmol/L, reference range (RR) 3.5-5.0 mmol/L). He was admitted to the intensive care unit (ICU) and was treated with potassium replacement. The patient later admitted that he had exposed himself to weight loss agents of unknown nature, purchased online, and large carbohydrate loads in preparation for the competition. He made a full recovery after a few days and discharged himself from the hospital against medical advice. The severe hypokalemia was thought to be caused by several mechanisms to be discussed in this report. With the ever rising number of new fitness centers recently, the ease of online purchasing of almost any drug, and the increasing numbers of youngsters getting into the bodybuilding arena, clinicians should be able to recognize the possible causes of sudden severe hypokalemia in these patients in order to revert the pathophysiology.

Life-Threatening Hypokalemic Paralysis in a Young Bodybuilder

Science.gov (United States)

Cheung, Kitty K. T.; So, Wing-Yee; Kong, Alice P. S.; Ma, Ronald C. W.; Chow, Francis C. C.

2014-01-01

We report a case of life-threatening hypokalemia in a 28-year-old bodybuilder who presented with sudden onset bilateral lower limbs paralysis few days after his bodybuilding competition. His electrocardiogram (ECG) showed typical u-waves due to severe hypokalemia (serum potassium 1.6 mmol/L, reference range (RR) 3.5–5.0 mmol/L). He was admitted to the intensive care unit (ICU) and was treated with potassium replacement. The patient later admitted that he had exposed himself to weight loss agents of unknown nature, purchased online, and large carbohydrate loads in preparation for the competition. He made a full recovery after a few days and discharged himself from the hospital against medical advice. The severe hypokalemia was thought to be caused by several mechanisms to be discussed in this report. With the ever rising number of new fitness centers recently, the ease of online purchasing of almost any drug, and the increasing numbers of youngsters getting into the bodybuilding arena, clinicians should be able to recognize the possible causes of sudden severe hypokalemia in these patients in order to revert the pathophysiology. PMID:24660073

Radiological protection guidance for radioactive patients -new data for therapeutic 131I

International Nuclear Information System (INIS)

Hilditch, T.E.; Watson, W.S.; Connell, J.M.C.; Davies, D.L.; Alexander, W.D.

1991-01-01

Thyroidal retention of 131 I was measured in 77 thyrotoxic patients over a period of 1-50 days after a first therapeutic administration of the radionuclide. Mean 131 I activity in the gland (± S.D.) at 1 day was 56.1 ± 11.1% of the administered dose activity and thereafter retention followed a single exponential decay pattern with a mean effective half-life (± S.E.M.) of 6.35 ± 0.14 days. In patients who required further 131 I therapy, there was evidence that retention could be markedly reduced if there was virtual ablation of thyroid tissue. It is proposed that these retention data can be used to determine body radioactivity at any interval after the administration of 131 I for treatment of thyrotoxicosis, thus obviating the need for serial measurements in every individual patient. (author)

Thyroid emergencies.

Science.gov (United States)

Klubo-Gwiezdzinska, Joanna; Wartofsky, Leonard

2012-03-01

This review presents current knowledge about the thyroid emergencies known as myxedema coma and thyrotoxic storm. Understanding the pathogenesis of these conditions, appropriate recognition of the clinical signs and symptoms, and their prompt and accurate diagnosis and treatment are crucial in optimizing survival. Copyright © 2012 Elsevier Inc. All rights reserved.

Chaos to periodicity and periodicity to chaos by periodic perturbations in the Belousov-Zhabotinsky reaction

International Nuclear Information System (INIS)

Li Qianshu; Zhu Rui

2004-01-01

A three-variable model of the Belousov-Zhabotinsky reaction system subject to external sinusoidal perturbations is investigated by means of frequency spectrum analysis. In the period-1 window of the model, the transitions from periodicity to chaos are observed; in the chaotic window, the transitions from chaos to periodicity are found. The former might be understood by the circle map of two coupled oscillators, and the latter is partly explained by the resonance between the main frequency of the chaos and the frequency of the external periodic perturbations

Body height and weight of patients with childhood onset and adult onset thyrotoxicosis.

Science.gov (United States)

Takamatsu, J; Kobe, N; Ito, M; Ohsawa, N

1999-03-01

The present study has compared body height and weight of thyrotoxic female patients of childhood onset and adult onset. The body height of 141 out of 143 (99%) adult-onset thyrotoxic patients was within the range of mean +/- 2SD for the age-matched general Japanese female population. On the other hand, in 42 patients with childhood-onset thyrotoxicosis, 6 (14%) had their height being greater than the mean + 2SD of general population, and 34 (81%) were taller than the mean value. In 86 patients with siblings, 42 (49%) were at least 2 cm taller than their sisters, and 26 (30%) were more than 2 cm shorter than their sisters. The body weight of 27 out of 42 (68%) patients younger than 20 years was not decreased but was even greater than the mean value for the age-matched general population. The results indicate that excessive thyroid hormone in vivo enhances body height in humans. The increased body weight in some young patients suggests that enhanced dietary intake due to increased appetite in hyperthyroidism has overcome the energy loss with increased metabolism.

Thyrotoxic Dysphagia in an 82-Year-Old Male

OpenAIRE

Parperis, Konstantinos; Dadu, Ramona; Hoq, Sheikh; Argento, Vivian

2011-01-01

Dysphagia is a common problem in elderly patients and a rare manifestation of Graves' disease. We report a case of an 82-year-old male who presented with a 4-week history of dysphagia and weight loss. Workup for his dysphagia with upper endoscopy, MRI brain, electromyography, acetyl-cholinesterase receptor antibodies, and voltage-gated calcium channel antibodies were negative. Modified Barium swallow test showed oropharyngeal dysphagia. Thyroid function tests that revealed hyperthyroidism and...

Thyrotoxic Dysphagia in an 82-Year-Old Male

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Konstantinos Parperis

2011-01-01

Full Text Available Dysphagia is a common problem in elderly patients and a rare manifestation of Graves' disease. We report a case of an 82-year-old male who presented with a 4-week history of dysphagia and weight loss. Workup for his dysphagia with upper endoscopy, MRI brain, electromyography, acetyl-cholinesterase receptor antibodies, and voltage-gated calcium channel antibodies were negative. Modified Barium swallow test showed oropharyngeal dysphagia. Thyroid function tests that revealed hyperthyroidism and antibodies to TSH-receptor were positive. Based on the above findings, we considered Graves' disease as the most likely diagnosis. Patient was treated with methimazole and beta-blockers and subsequently his dysphagia resolved. This paper highlights the importance to clinicians of considering thyrotoxicosis as possible diagnosis in an elderly patient presenting with unexplained dysphagia.

Renal abnormalities in congenital chloride diarrhea

International Nuclear Information System (INIS)

Al-Hamad, Nadia M.; Al-Eisa, Amal A.

2004-01-01

Congenital chloride diarrhea CLD is a rare autosomal recessive disorder caused by a defect in the chloride/ bicarbonate exchange in the ileum and colon. It is characterized by watery diarrhea, abdominal distension, hypochloremic hypokalemic metabolic alkalosis with high fecal content of chloride >90 mmol/l. We report 3 patients with CLD associated with various renal abnormalities including chronic renal failure secondary to renal hypoplasia, nephrocalcinosis and congenital nephrotic syndrome. (author)

Photolysis of Periodate and Periodic Acid in Aqueous Solution

DEFF Research Database (Denmark)

Sehested, Knud; Kläning, U. K.

1978-01-01

The photochemistry of periodate and periodic acid in aqueous solution was studied (i) by quantum yield measurements at low light intensity (ii) by flash photolysis, and (iii) by photolysis of glassy samples at 77 K. The photochemical studies were supplemented with pulse radiolysis studies...... of aqueous periodate solutions and with kinetic studies using stopped-flow technique. In strongly alkaline solution the photodecomposition of periodate proceeds via formation of O– and IVI. At pH solution O3 P is formed in a small...

A novel CLCN5 mutation in a boy with Bartter-like syndrome and partial growth hormone deficiency.

Science.gov (United States)

Bogdanović, Radovan; Draaken, Markus; Toromanović, Alma; Dordević, Maja; Stajić, Natasa; Ludwig, Michael

2010-11-01

Dent disease is an X-linked recessive disorder affecting the proximal tubule and is characterized by low-molecular-weight proteinuria (LMWP), hypercalciuria, nephrocalcinosis/nephrolithiasis with a variable number of features of Fanconi syndrome. It is most often associated with mutations in CLCN5, which encodes the endosomal electrogenic chloride/proton exchanger ClC-5. Renal acidification abnormalities are only rarely seen in Dent disease, whereas the hypokalemic metabolic alkalosis associated with hyperreninemic hyperaldosteronism (Bartter-like syndrome) has been reported in only one patient so far. We report on a 5-year-old boy with Dent disease caused by mutation in CLCN5 gene, c.1073G>A, who presented with hypokalemic metabolic alkalosis and hyperreninemic hyperaldosteronism persisting over the entire follow-up. No mutations were found in NKCC2, ROMK, NCCT, or ClC-Kb genes. In addition, the patient exhibited growth failure associated with partial growth hormone (GH) deficiency. Coexistence of Bartter-like syndrome features with LMWP should prompt a clinician to search for Dent disease. The Bartter syndrome phenotype seen in Dent disease patients may represent a distinct form of Bartter syndrome, the exact mechanism of which has yet to be fully elucidated. Growth delay that persists in spite of appropriate therapy should raise suspicion of other causes, such as GH deficiency.

Thyroid disease and the nervous system.

Science.gov (United States)

Wood-Allum, Clare A; Shaw, Pamela J

2014-01-01

Thyroid disorders are common in the general population and in hospitalized patients. Thyroid disease may present first with neurological complications or else may occur concurrently in patients suffering other neurological disorders, particularly those with an autoimmune etiology. For this reason neurologists will commonly encounter patients with thyroid disease. This chapter provides an overview of the neurological complications and associations of disorders of the thyroid gland. Particular emphasis is placed on conditions such as thyrotoxic periodic paralysis and myxedema coma in which the underlying thyroid disorder may be occult leading to a first, often emergency, presentation to a neurologist. Information about clinical features, diagnosis, pathogenesis, therapy, and prognosis is provided. Emphasis is placed on those aspects most likely to be relevant to the practicing neurologist and the interested reader is directed to references to good, recent review articles for further information. © 2014 Elsevier B.V. All rights reserved.

Metabolic alkalosis secondary to baking soda treatment of a diaper rash.

Science.gov (United States)

Gonzalez, J; Hogg, R J

1981-06-01

A 4-month-old infant was seen with hypokalemic metabolic alkalosis that was associated with prior application of liberal amounts of sodium bicarbonate (baking soda) to a diaper rash. After exclusion of other etiologies of the infant's acid-base disturbance, a complete resolution occurred following discontinuation of the baking soda applications. This case report provides a reminder of the significant side effects that may result from the excessive use of a seemingly harmless household substance.

Positive periodic solutions of delayed periodic Lotka-Volterra systems

International Nuclear Information System (INIS)

Lin Wei; Chen Tianping

2005-01-01

In this Letter, for a general class of delayed periodic Lotka-Volterra systems, we prove some new results on the existence of positive periodic solutions by Schauder's fixed point theorem. The global asymptotical stability of positive periodic solutions is discussed further, and conditions for exponential convergence are given. The conditions we obtained are weaker than the previously known ones and can be easily reduced to several special cases

From Periodic Properties to a Periodic Table Arrangement

Science.gov (United States)

Besalú, Emili

2013-01-01

A periodic table is constructed from the consideration of periodic properties and the application of the principal components analysis technique. This procedure is useful for objects classification and data reduction and has been used in the field of chemistry for many applications, such as lanthanides, molecules, or conformers classification.…

A STUDY ON CLINICAL AND AETIOLOGICAL PROFILE OF HYPOKALAEMIC PARALYSIS IN A TERTIARY CARE HOSPITAL

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Kekathi Vidyasagar

2016-08-01

Full Text Available BACKGROUND Hypokalaemic periodic paralysis is a rare disorder characterised by transient attacks of flaccid paralysis of varying intensity and frequency. Although mostly familial in aetiology, several sporadic cases with different causes have been reported. There are two groups of disorders predominantly that causes hypokalaemic paralysis. One group is due to transcellular shift of potassium and other is due to loss of potassium from body either through GI tract or through renal system. MATERIAL AND METHODS Here we report a study on the clinical and aetiological profile of 30 cases of hypokalaemic paralysis admitted in our institution between January 2014 to January 2016. RESULTS The aetiological workup of all the patients was done which revealed thyrotoxic periodic paralysis as the major cause in 12 of 30 patients. Three rare causes of hypokalaemia have been diagnosed which included Bartter’s syndrome, Mixed Connective tissue disorder, Sjogren’s syndrome. Vomiting and diarrhoea was seen in 12 of 30 patients. CONCLUSION Hypokalaemic periodic paralysis is a heterogenous group of disorder. A significant number of patients had thyroid disorders mostly in the form of thyrotoxicosis, non-renal and renal loss of potassium like diarrhoea and vomiting. Early recognition and prompt management of these conditions is essential to prevent residual deformity and further attacks in future.

Bounded and Periodic Solutions of Semilinear Impulsive Periodic System on Banach Spaces

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Wei W

2008-01-01

Full Text Available Abstract A class of semilinear impulsive periodic system on Banach spaces is considered. First, we introduce the -periodic PC-mild solution of semilinear impulsive periodic system. By virtue of Gronwall lemma with impulse, the estimate on the PC-mild solutions is derived. The continuity and compactness of the new constructed Poincaré operator determined by impulsive evolution operator corresponding to homogenous linear impulsive periodic system are shown. This allows us to apply Horn's fixed-point theorem to prove the existence of -periodic PC-mild solutions when PC-mild solutions are ultimate bounded. This extends the study on periodic solutions of periodic system without impulse to periodic system with impulse on general Banach spaces. At last, an example is given for demonstration.

Salbutamol Abuse is Associated with Ventricular Fibrillation

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Emin UYSAL

2015-06-01

Full Text Available SUMMARY: Salbutamol-induced cardiac complications are well-established. Herein, we describe a case of a 24-year female who was admitted to the emergency department because of a suicide attempt with salbutamol (76 mg. Salbutamol abuse induced the development of supraventricular tachycardia and ventricular fibrillation. Regular sinus rhythm was restored with defibrillation. The hypokalemic patient who stayed in the intensive care unit was discharged after 48 hours of hospitalization. Key words: Salbutamol, suicide, ventricular fibrillation

Homespun remedy, homespun toxicity: baking soda ingestion for dyspepsia.

Science.gov (United States)

Ajbani, Keyur; Chansky, Michael E; Baumann, Brigitte M

2011-04-01

A 68-year-old man presented to the Emergency Department with a severe metabolic alkalosis after ingesting large quantities of baking soda to treat his dyspepsia. His underlying pulmonary disease and a progressively worsening mental status necessitated intubation for respiratory failure. Laboratory studies revealed a hyponatremic, hypochloremic, hypokalemic metabolic alkalosis. The patient was successfully treated after cessation of the oral bicarbonate, initiation of intravenous hydration, and correction of electrolyte abnormalities. Copyright © 2011 Elsevier Inc. All rights reserved.

Unusual case of failure to thrive: Type III Bartter syndrome.

Science.gov (United States)

Agrawal, S; Subedi, K; Ray, P; Rayamajhi, A

2016-09-01

Bartter syndrome Type III is a rare autosomal recessive disorder resulting from an inherited defect in the thick ascending limb of the loop of henle of the nephrons in kidney. The typical clinical manifestations in childhood are failure to thrive and recurrent episodes of vomiting. Typical laboratory findings which help in the diagnosis are hypokalemic metabolic alkalosis, hypomagnesemia and hypercalciuria. We report a case of Type III Bartter syndrome not responding to repeated conventional treatment of failure to thrive.

Entropy method of measuring and evaluating periodicity of quasi-periodic trajectories

Science.gov (United States)

Ni, Yanshuo; Turitsyn, Konstantin; Baoyin, Hexi; Junfeng, Li

2018-06-01

This paper presents a method for measuring the periodicity of quasi-periodic trajectories by applying discrete Fourier transform (DFT) to the trajectories and analyzing the frequency domain within the concept of entropy. Having introduced the concept of entropy, analytical derivation and numerical results indicate that entropies increase as a logarithmic function of time. Periodic trajectories typically have higher entropies, and trajectories with higher entropies mean the periodicities of the motions are stronger. Theoretical differences between two trajectories expressed as summations of trigonometric functions are also derived analytically. Trajectories in the Henon-Heiles system and the circular restricted three-body problem (CRTBP) are analyzed with the indicator entropy and compared with orthogonal fast Lyapunov indicator (OFLI). The results show that entropy is a better tool for discriminating periodicity in quasiperiodic trajectories than OFLI and can detect periodicity while excluding the spirals that are judged as periodic cases by OFLI. Finally, trajectories in the vicinity of 243 Ida and 6489 Golevka are considered as examples, and the numerical results verify these conclusions. Some trajectories near asteroids look irregular, but their higher entropy values as analyzed by this method serve as evidence of frequency regularity in three directions. Moreover, these results indicate that applying DFT to the trajectories in the vicinity of irregular small bodies and calculating their entropy in the frequency domain provides a useful quantitative analysis method for evaluating orderliness in the periodicity of quasi-periodic trajectories within a given time interval.

Hyperfunctioning thyroid nodules in children and adolescents.

Science.gov (United States)

de Luca, F; Chaussain, J L; Job, J C

1986-01-01

Eight children and adolescents, seven female and one male, aged 7.1 to 15.0 years, referred over a 12-year period for a solitary mass in an otherwise normal thyroid gland, exhibited a hyperfunctioning nodule on thyroid scintiscan. Tracer uptake in the surrounding thyroid tissue was reduced or completely suppressed, but could be restored after TSH stimulation. Only one patient had mild clinical hyperthyroidism with normal T4 but increased T3 serum levels and blunted TSH responsiveness to TRH. A similar hormonal pattern suggestive of subclinical hyperthyroidism was found in three other subjects who were clinically euthyroid. One patient initially euthyroid progressed to subclinical hyperthyroidism two years later. In the whole group a significant negative relationship was found between serum T3 level and TRH-stimulated TSH peak (r = -0.829, p less than 0.02). All the patients underwent selective surgery after a 3-month to 2-year period of follow-up. Microscopic examination was consistent with adenoma in seven patients, while in one case a well-encapsulated papillary adenocarcinoma was found. Though hyperfunctioning nodules are seldom malignant, their surgical removal must be recommended when they become thyrotoxic, exceed 3 cm or show progressive enlargement.

Vertebrate fauna of the Roman period, migrations period and Medieval period in Vojvodina (Serbia

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Radmanović Darko P.

2014-01-01

Full Text Available Based on current published and unpublished research results, a total of 16 vertebrate species members of mammal (Mammalia, bird (Aves and osteichthyes (Osteichthyes classes have been registered at 11 archaeological sites from the Roman Period in Vojvodina. Mammals dominate with 12 species and one genus, birds are present with 3 species, and osteichthyes with one. From the Migration Period, at 9 sites, 22 vertebrate species have been registered, of which 13 species and one genus of mammals, 4 species and one genus of birds, and 5 species from the Osteichthyes class. At 8 sites from the Medieval Period, 16 vertebrate species have been registered. Mammals are the most numerous class with 10 species and one genus, while birds are present with 4 species and one genus. Furthermore, two species of osteichthyes have also been registered.

Commuting periodic operators and the periodic Wigner function

International Nuclear Information System (INIS)

Zak, J

2004-01-01

Commuting periodic operators (CPO) depending on the coordinate x-hat and the momentum p-hat operators are defined. The CPO are functions of the two basic commuting operators exp(i x-hat 2π/a) and exp(i/h p-hat a), with a being an arbitrary constant. A periodic Wigner function (PWF) w(x, p) is defined and it is shown that it is applicable in a normal expectation value calculation to the CPO, as done in the original Wigner paper. Moreover, this PWF is non-negative everywhere, and it can therefore be interpreted as an actual probability distribution. The PWF w(x, p) is shown to be given as an expectation value of the periodic Dirac delta function in the phase plane. (letter to the editor)

Forward Period Analysis Method of the Periodic Hamiltonian System.

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Pengfei Wang

Full Text Available Using the forward period analysis (FPA, we obtain the period of a Morse oscillator and mathematical pendulum system, with the accuracy of 100 significant digits. From these results, the long-term [0, 1060] (time unit solutions, ranging from the Planck time to the age of the universe, are computed reliably and quickly with a parallel multiple-precision Taylor series (PMT scheme. The application of FPA to periodic systems can greatly reduce the computation time of long-term reliable simulations. This scheme provides an efficient way to generate reference solutions, against which long-term simulations using other schemes can be tested.

STUDIES OF THE RENAL CONCENTRATING MECHANISM IN HUMANS. I. THE EFFECT OF HYPERTHYROIDISM,

Science.gov (United States)

Summary: (1) The maximum urinary osmolality after dehydration and exogenous vasopressin was significantly decreased during thyrotoxicosis in... thyrotoxicosis , TcH2O during a moderate mannitol diuresis was unchanged in most patients. The data suggest that the decreased Umax and normal TcH2O...in thyrotoxic individuals is probably caused by an increase in medullary blood flow with a decrease in medullary osmolality. (2) Renal hemodynamics

Affective cycling in thyroid disease

International Nuclear Information System (INIS)

Tapp, A.

1988-01-01

Depression in an elderly man with primary recurrent unipolar depression responded to radioactive iodine treatment of a thyrotoxic nodule, without the addition of psychotropic medications. Two months later, manic symptoms developed concomitant with the termination of the hyperthyroid state secondary to the radioactive iodine treatment. Clinical implications of these findings in relation to the possible mechanism of action of thyroid hormones on affective cycling are discussed

Thyroidectomy for the treatment of Graves’ thyrotoxicosis in thioamide-induced agranulocytosis and sepsis

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Colin L Knight

2017-09-01

Full Text Available A 51 year old man presented with sepsis in the setting of thioamide-induced agranulocytosis. Empiric broad-spectrum antibiotics was followed by directed narrow-spectrum antibiotics, and his neutrophil count recovered with support from granulocyte-colony stimulating factor (G-CSF analogue transfusions. After a brief period of multi-modal therapy for nine days including potassium iodide (Lugol’s iodine, cholestyramine, propanolol and lithium to temper his persisting hyperthyroidism, a total thyroidectomy was performed while thyroid hormone levels remained at thyrotoxic levels. Postoperative recovery was uncomplicated and he was discharged home on thyroxine. There is limited available evidence to guide treatment in this unique cohort of patients who require prompt management to avert impending clinical deterioration. This case report summarises the successful emergent control of thyrotoxicosis in the setting of thioamide-induced agranulocytosis complicated by sepsis, and demonstrates the safe use of multi-modal pharmacological therapies in preparation for total thyroidectomy.

The Periodic Pyramid

Science.gov (United States)

Hennigan, Jennifer N.; Grubbs, W. Tandy

2013-01-01

The chemical elements present in the modern periodic table are arranged in terms of atomic numbers and chemical periodicity. Periodicity arises from quantum mechanical limitations on how many electrons can occupy various shells and subshells of an atom. The shell model of the atom predicts that a maximum of 2, 8, 18, and 32 electrons can occupy…

Thyrotoxic Neuropathy: A rare cause of acute flaccid paraplegia

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Aiman K. Al-Wahaibi

2018-01-01

Full Text Available Acute polyneuropathy is a rare manifestation of severe hyperthyroidism. We report a 22-year-old Omani male who presented to the Sohar Hospital, Sohar, Oman, in 2016 with acute-onset rapidly progressive flaccid areflexic paraplegia as the presenting manifestation of thyrotoxicosis. Nerve conduction studies revealed mixed axonal and demyelinating polyneuropathy in both the motor and sensory nerves. Treatment of the hyperthyroidism with β-blockers and carbimazole along with physiotherapy resulted in the patient’s full recovery and the alleviation of his symptoms. Besides highlighting this rare association, this report underscores the importance of including thyroid function tests in the evaluation of patients with acute polyneuropathy.

Amiodarone-Induced Thyrotoxic Thyroiditis: A Diagnostic and Therapeutic Challenge

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Umang Barvalia

2014-01-01

Full Text Available Amiodarone is an iodine-based, potent antiarrhythmic drug bearing a structural resemblance to thyroxine (T4. It is known to produce thyroid abnormalities ranging from abnormal thyroid function testing to overt hypothyroidism or hyperthyroidism. These adverse effects may occur in patients with or without preexisting thyroid disease. Amiodarone-induced thyrotoxicosis (AIT is a clinically recognized condition commonly due to iodine-induced excessive synthesis of thyroid, also known as type 1 AIT. In rare instances, AIT is caused by amiodarone-induced inflammation of thyroid tissue, resulting in release of preformed thyroid hormones and a hyperthyroid state, known as type 2 AIT. Distinguishing between the two states is important, as both conditions have different treatment implications; however, a mixed presentation is not uncommon, posing diagnostic and treatment challenges. We describe a case of a patient with amiodarone-induced type 2 hyperthyroidism and review the current literature on the best practices for diagnostic and treatment approaches.

Middle Helladic Period

DEFF Research Database (Denmark)

Sarri, Kalliopi

1999-01-01

and their quality was improved considerably toward the end of this period. The profound cultural innovations of the Middle Helladic period were initially interpreted as a result of violent population movement and troubles provoked by the coming of the first Indo-European races. However, this matter does no more...... Helladic period is considered as a period of economic and social decline it was the time during which the mainland features merged with the insular influence, that is all the Aegean elements which led to the creation of the Mycenaean civilization were mixed in a creative way....

Periodicity and quasi-periodicity for super-integrable hamiltonian systems

International Nuclear Information System (INIS)

Kibler, M.; Winternitz, P.

1990-01-01

Classical trajectories are calculated for two Hamiltonian systems with ring shaped potentials. Both systems are super-integrable, but not maximally super-integrable, having four globally defined single-valued integrals of motion each. All finite trajectories are quasi-periodical; they become truly periodical if a commensurability condition is imposed on an angular momentum component

Explore the Possibility of Early Clinical Diagnosis of Endocrine Ophthalmopathy Based on Eye Symptoms of Hyperthyroidism

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V. G. Likhvantseva

2016-01-01

Full Text Available Purpose: to study the possibility of early clinical diagnosis of endocrine ophthalmopathy based on ocular symptoms of hyperthyroidism. Patients and methods: we analyzed the prevalence of ocular symptoms of hyperthyroidism in 139 patients (278 orbits with newly diagnosed endocrine ophthalmopathy (group 1, developed on the background of diffuse toxic goiter. The comparison group consisted of 80 patients (160 orbits with newly diagnosed diffuse toxic goiter with no radiographic evidence of endocrine ophthalmopathy (group 2. All patients were examined by an ophthalmologist and endocrinologist. We analyzed the prevalence of ocular symptoms of hyperthyroidism (symptom Dalrymple’, Mobius’, Zenger’, and combinations thereof, often encountered in diffuse toxic goiter, flowing with endocrine ophthalmopathy, and/or lack thereof - in the group of “thyrotoxic exophthalmos”. We took into account the frequency distribution of these clinical signs, and their combinations. We analyzed the clinical sensitivity and specificity of diagnosis based on the three most common symptoms, and their combinations, associated both with thyrotoxicosis and with endocrine ophthalmopathy. Results: Dalrymple’ symptom, is more common in thyrotoxic exophthalmos than with endocrine ophthalmopathy (compared to 100.0% versus 61.9 %, p<0,001. This suggests that Dalrymple’ symptom leads to over diagnosis aspect endocrine ophthalmopathy. It is obvious that it can be used to recognize and thyrotoxic exophthalmos hyperthyroidism, but you cann’t credibly claim based on orbit about the presence of the disease. In this aspect, the greatest practical interest to provide a comparative assessment of the frequency of detection of symptoms of Mobius’ and Zenger’ and their combinations in a population of endocrine ophthalmopathy and in the group of thyrotoxic exophthalmos. Significantly more symptoms Zenger’ and Mobius’ developed with endocrine ophthalmopathy (66,2% and 81

Expanding the spectrum of genetic mutations in antenatal Bartter syndrome type II.

Science.gov (United States)

Fretzayas, Andreas; Gole, Evangelia; Attilakos, Achilleas; Daskalaki, Anna; Nicolaidou, Polyxeni; Papadopoulou, Anna

2013-06-01

Bartter syndrome (BS) is a group of genetic disorders characterized by hypokalemic metabolic alkalosis, hyponatremia and elevated renin and aldosterone plasma concentrations. BS type II is caused by mutations in the KCNJ1 gene and usually presents with transient hyperkalemia. We report here a novel KCNJ1 mutation in a male neonate, prematurely born after a pregnancy complicated by polyhydramnios. The infant presented with typical clinical and laboratory findings of BS type II, such as hyponatremia, hypochloremic metabolic alkalosis, severe weight loss, elevated renin and aldosterone levels and transient hyperkalemia in the early postnatal period, which were later normalized. Molecular analysis revealed a compound heterozygous mutation in the KCNJ1 gene, consisting of a novel K76E and an already described V315G mutation, both affecting functional domains of the channel protein. Typical manifestations of antenatal BS in combination with hyperkalemia should prompt the clinician to search for mutations in the KCNJ1 gene first. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

Thyroiditis: Symptoms to sequelae - An Indian experience

International Nuclear Information System (INIS)

Sneha, S.; Krishna, B.A.; Madhavi, C.; Sangeeta, T.; Rijju, G.

2002-01-01

Introduction: Thyroiditis presents with symptoms varying from thyrotoxicosis to hypothyroidism. In fairly a large number of patients the symptoms are very subtle and hence clinical diagnosis is difficult to make without laboratory assistance. In view of this we undertook a study to assess the patterns of clinical presentation and the behavioral pattern of patients with thyroiditis. Materials and Methods: Totally 43 patients were included in the study with clinical suspicion of thyroiditis. 31 patients presented with symptoms of thyrotoxicosis while 6 patients presented with hypothyroid symptoms. Six patients presented with history of acute upper respiratory tract infection with tender thyromegaly and euthyroid status. These patients were subjected to thyroid scan (43 patients), sonography (6 patients), thyroid antibody levels estimation (43 patients), FNAC evaluation (3 patients) and T3, T4, TSH estimation (43 patients). The patients were followed up for a period of 6 months to 2 years. Clinical evaluation and T3, T4 and TSH evaluation was performed. Result: 19 of the 31 patients (61.29%) who presented with thyrotoxicosis progressed to hypothyroid state both clinically and biochemically. 11 of the 31 patients (35.48%) reverted to euthyroid status. One patient continued to maintain thyrotoxic state at the end of 2 years and was treated with antithyroid measures. In the hypothyroid group of six patients, four patients continued to maintain hypothyroid state while two patients reverted to euthyroid status during follow up. In the euthyroid group of six patients four patients developed hypothyroid status and the other two patients remained euthyroid. The 99m- Tco4 scan demonstrated poor and patchy uptake in all the patients. Conclusion: Our study demonstrated that majority of the patients (72.09%) of thyroiditis present with thyrotoxic symptoms. The sequelae of hypothyroidism was seen in 61.29% of patients in this group. We observed an interesting finding of patients

PERIOD ESTIMATION FOR SPARSELY SAMPLED QUASI-PERIODIC LIGHT CURVES APPLIED TO MIRAS

Energy Technology Data Exchange (ETDEWEB)

He, Shiyuan; Huang, Jianhua Z.; Long, James [Department of Statistics, Texas A and M University, College Station, TX (United States); Yuan, Wenlong; Macri, Lucas M., E-mail: lmacri@tamu.edu [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX (United States)

2016-12-01

We develop a nonlinear semi-parametric Gaussian process model to estimate periods of Miras with sparsely sampled light curves. The model uses a sinusoidal basis for the periodic variation and a Gaussian process for the stochastic changes. We use maximum likelihood to estimate the period and the parameters of the Gaussian process, while integrating out the effects of other nuisance parameters in the model with respect to a suitable prior distribution obtained from earlier studies. Since the likelihood is highly multimodal for period, we implement a hybrid method that applies the quasi-Newton algorithm for Gaussian process parameters and search the period/frequency parameter space over a dense grid. A large-scale, high-fidelity simulation is conducted to mimic the sampling quality of Mira light curves obtained by the M33 Synoptic Stellar Survey. The simulated data set is publicly available and can serve as a testbed for future evaluation of different period estimation methods. The semi-parametric model outperforms an existing algorithm on this simulated test data set as measured by period recovery rate and quality of the resulting period–luminosity relations.

Periodic Solutions and S-Asymptotically Periodic Solutions to Fractional Evolution Equations

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Jia Mu

2017-01-01

Full Text Available This paper deals with the existence and uniqueness of periodic solutions, S-asymptotically periodic solutions, and other types of bounded solutions for some fractional evolution equations with the Weyl-Liouville fractional derivative defined for periodic functions. Applying Fourier transform we give reasonable definitions of mild solutions. Then we accurately estimate the spectral radius of resolvent operator and obtain some existence and uniqueness results.

Contrast induced hyperthyroidism due to iodine excess

OpenAIRE

Mushtaq, Usman; Price, Timothy; Laddipeerla, Narsing; Townsend, Amanda; Broadbridge, Vy

2009-01-01

Iodine induced hyperthyroidism is a thyrotoxic condition caused by exposure to excessive iodine. Historically this type of hyperthyroidism has been described in areas of iodine deficiency. With advances in medicine, iodine induced hyperthyroidism has been observed following the use of drugs containing iodine—for example, amiodarone, and contrast agents used in radiological imaging. In elderly patients it is frequently difficult to diagnose and control contrast related hyperthyroidism, as most...

On complex periodic motions and bifurcations in a periodically forced, damped, hardening Duffing oscillator

International Nuclear Information System (INIS)

Guo, Yu; Luo, Albert C.J.

2015-01-01

In this paper, analytically predicted are complex periodic motions in the periodically forced, damped, hardening Duffing oscillator through discrete implicit maps of the corresponding differential equations. Bifurcation trees of periodic motions to chaos in such a hardening Duffing oscillator are obtained. The stability and bifurcation analysis of periodic motion in the bifurcation trees is carried out by eigenvalue analysis. The solutions of all discrete nodes of periodic motions are computed by the mapping structures of discrete implicit mapping. The frequency-amplitude characteristics of periodic motions are computed that are based on the discrete Fourier series. Thus, the bifurcation trees of periodic motions are also presented through frequency-amplitude curves. Finally, based on the analytical predictions, the initial conditions of periodic motions are selected, and numerical simulations of periodic motions are carried out for comparison of numerical and analytical predictions. The harmonic amplitude spectrums are also given for the approximate analytical expressions of periodic motions, which can also be used for comparison with experimental measurement. This study will give a better understanding of complex periodic motions in the hardening Duffing oscillator.

Theoretical growth rates, periods, and pulsation constants for long-period variables

International Nuclear Information System (INIS)

Fox, M.W.; Wood, P.R.

1982-01-01

Theoretical values of the growth rate, period, and pulsation constant for the first three radial pulsation modes in red giants (Population II and galactic disk) and supergiants have been derived in the linear, nonadiabatic approximation. The effects of altering the surface boundary conditions, the effective temperature (or mixing length), and the opacity in the outer layers have been explored. In the standard models, the Q-value for the first overtone can be much larger (Q 1 1 roughly-equal0.04); in addition, the Q-value for the fundamental mode is reduced from previous values, as is the period ratio P 0 /P 1 . The growth rate for the fundamental mode is found to increase with luminosity on the giant branch while the growth rate for the first overtone decreases. Dynamical instabilities found in previous adiabatic models of extreme red giants do not occur when nonadiabatic effects are included in the models. In some massive, luminous models, period ratios P 0 /P 1 approx.7 occur when P 0 approx.2000--5000 days; it is suggested that the massive galactic supergiants and carbon stars which have secondary periods Papprox.2000--7000 days and primary periods Papprox.300--700 days are first-overtone pulsators in which the long secondary periods are due to excitation of the fundamental mode. Some other consequences of the present results are briefly discussed, with particular emphasis on the mode of pulsation of the Mira variables. Subject headings: stars: long-period variables: stars: pulsation: stars: supergiants

Quasi-periodic solutions of nonlinear beam equations with quintic quasi-periodic nonlinearities

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Qiuju Tuo

2015-01-01

Full Text Available In this article, we consider the one-dimensional nonlinear beam equations with quasi-periodic quintic nonlinearities $$ u_{tt}+u_{xxxx}+(B+ \\varepsilon\\phi(tu^5=0 $$ under periodic boundary conditions, where B is a positive constant, $\\varepsilon$ is a small positive parameter, $\\phi(t$ is a real analytic quasi-periodic function in t with frequency vector $\\omega=(\\omega_1,\\omega_2,\\dots,\\omega_m$. It is proved that the above equation admits many quasi-periodic solutions by KAM theory and partial Birkhoff normal form.

Minimum period and the gap in periods of Cataclysmic binaries

International Nuclear Information System (INIS)

Paczynski, B.; Sienkiewicz, R.

1983-01-01

The 81 minute cutoff to the orbital periods of hydrogen-rich cataclysmic binaries is consistent with evolution of those systems being dominated by angular momentum losses due to gravitational radiation. Unfortunately, many uncertainties, mainly poorly known atmospheric opacities below 2000 K, make is physically impossible to verify the quadrupole formula for gravitational radiation by using the observed cutoff at 81 minutes. The upper boundary of the gap in orbital periods observed at about 3 hours is almost certainly due to enhanced angular momentum losses from cataclysmic binaries which have longer periods. The physical mechanism of those losses is not identified, but a possible importance of stellar winds is pointed out. The lower boundary of the gap may be explained with the oldest cataclysmic binaries, whose periods evolved past the minimum at 81 minutes and reached the value of 2 hours within about 12 x 10 9 years after the binary had formed. Those binaries should have secondary components of only 0.02 solar masses, and their periods could be used to estimate ages of the oldest cataclysmic stars, and presumably the age of Galaxy. An alternative explanation for the gap requires that binaries should be detached while crossing the gap. A possible mechanism for this phenomenon is discussed. It requires the secondary components to be about 0.2 solar masses in the binaries just below the gap

Super periodic potential

Science.gov (United States)

Hasan, Mohammd; Mandal, Bhabani Prasad

2018-04-01

In this paper we introduce the concept of super periodic potential (SPP) of arbitrary order n, n ∈I+, in one dimension. General theory of wave propagation through SPP of order n is presented and the reflection and transmission coefficients are derived in their closed analytical form by transfer matrix formulation. We present scattering features of super periodic rectangular potential and super periodic delta potential as special cases of SPP. It is found that the symmetric self-similarity is the special case of super periodicity. Thus by identifying a symmetric fractal potential as special cases of SPP, one can obtain the tunnelling amplitude for a particle from such fractal potential. By using the formalism of SPP we obtain the close form expression of tunnelling amplitude of a particle for general Cantor and Smith-Volterra-Cantor potentials.

Severe exacerbation of Andersen-Tawil syndrome secondary to thyrotoxicosis.

Science.gov (United States)

Díaz-Manera, Jordi; Querol, Luis; Alejaldre, Aída; Rojas-García, Ricard; Ramos-Fransi, Alba; Gallardo, Eduard; Illa, Isabel

2014-08-01

Thyrotoxic periodic paralysis (TPP) is a rare complication of hyperthyroidism characterized by episodes of weakness. Although TPP has been described in patients all over the world, it is especially frequent in Asiatic patients. Recently, two genomewide association studies have found a susceptibility locus on chromosome 17q24.3 near the KCNJ2 gene, which is responsible for another cause of periodic paralysis, the Andersen-Tawil syndrome (ATS). We report the first patient diagnosed with ATS with a de novo c.G899C mutation in the KCNJ2 gene in 2010 who developed an autoimmune hyperthyroidism and TPP in 2013. At the time of the ATS diagnosis other causes of periodic paralysis, including thyroid dysfunction, were ruled out. The condition of the patient, who had mild episodes of proximal weakness at follow-up, deteriorated dramatically in 2013, presenting continuous episodes of severe generalized weakness associated with low levels of potassium requiring frequent admissions to the hospital. After a few months, he also presented signs of hyperthyroidism, and a diagnosis of Grave's disease was made. In our opinion, this case clearly demonstrates that a dysfunction of the Kir2.1 potassium channel encoded by the KCNJ2 gene is a risk factor to develop TPP, and can be a useful tool to identify patients at risk in daily clinics.

SLAVIC LITERATURES IN DALMATIAN PERIODICALS IN THE PERIOD OF CROATIAN MODERNISM

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Robert Bacalja

2010-01-01

Full Text Available The paper analyzes translations and mediatorial articles from the Slavic literature published in Dalmatian newspapers and periodicals which contribute most to mediation during the period of Croatian Modernism. While periodicals in Dalmatia traditionally mediates from the Roman literature, especially from the Italian, in the examined corpus can be seen the remarkable reception of Slavic literature, particularly Russian.. The paradigm of the most recognized culture and literature in non Slavic world is desirable identity basis of the Croatian literature as a part of a large Slavic stem from romanticism to modernism. Mediation of Slavic literatures is examined on the corpus of newspapers and periodicals published in Dubrovnik, Split and Zadar (Crvena Hrvatska, Srđ, Sloboda, Jedinstvo/Novo jedinstvo, Novi vijek, Narodni list, Smotra dalmatinska, Iskra, Glasnik Matice dalmatinske, Lovor, etc..

The Discrete Beverton-Holt Model with Periodic Harvesting in a Periodically Fluctuating Environment

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Ziyad AlSharawi

2010-01-01

Full Text Available We investigate the effect of constant and periodic harvesting on the Beverton-Holt model in a periodically fluctuating environment. We show that in a periodically fluctuating environment, periodic harvesting gives a better maximum sustainable yield compared to constant harvesting. However, if one can also fix the environment, then constant harvesting in a constant environment can be a better option, especially for sufficiently large initial populations. Also, we investigate the combinatorial structure of the periodic sequence of carrying capacities and its effect on the maximum sustainable yield. Finally, we leave some questions worth further investigations.

Convergence acceleration of quasi-periodic and quasi-periodic-rational interpolations by polynomial corrections

OpenAIRE

Lusine Poghosyan

2014-01-01

The paper considers convergence acceleration of the quasi-periodic and the quasi-periodic-rational interpolations by application of polynomial corrections. We investigate convergence of the resultant quasi-periodic-polynomial and quasi-periodic-rational-polynomial interpolations and derive exact constants of the main terms of asymptotic errors in the regions away from the endpoints. Results of numerical experiments clarify behavior of the corresponding interpolations for moderate number of in...

Mean-periodic functions

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Carlos A. Berenstein

1980-01-01

Full Text Available We show that any mean-periodic function f can be represented in terms of exponential-polynomial solutions of the same convolution equation f satisfies, i.e., u∗f=0(μ∈E′(ℝn. This extends to n-variables the work of L. Schwartz on mean-periodicity and also extends L. Ehrenpreis' work on partial differential equations with constant coefficients to arbitrary convolutors. We also answer a number of open questions about mean-periodic functions of one variable. The basic ingredient is our work on interpolation by entire functions in one and several complex variables.

Distrofia muscular progressiva: alguns aspectos do diagnõstico diferencial

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Sylvio Saraiva

1960-09-01

Full Text Available The authors call attention to some clinical entities which are less known and more difficult to recognize and with which differential diagnosis of progressive muscular dystrophy should be made (infantile spinal muscular atrophy, amyotonia congenita, congenital acute anterior poliomyelitis, anthro-griposis multiplex, von Gierke's disease, central core disease, chronical polymyositis and dermatomyositis, thyrotoxic myopathy and menopausal dys- trophy. The importance of muscle biopsy in the differential diagnosis is emphasized.

Fatal thyrocardiac event

OpenAIRE

Khutia, Samit Kumar; Roy, Bhaskar; Mandal, Mohan Chandra; Das, Sabyasachi

2010-01-01

Atrial fibrillation occurs frequently (2-20%) in chronic hyperthyroidism patients. Poorly treated thyrotoxic patients may present with a life-threatening cerebrovascular accident giving little scope to revert the situation. At times, it is difficult to make a patient euthyroid with conventional management. The definitive treatment of choice is 131 I, radioiodine. An adjusted dose of an oral anticoagulant is highly efficacious for the prevention of all types of strokes. Timely intervention by...

Hypokalemic paralysis due to primary hyperaldosteronism simulating gitelman′s syndrome

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Kasifoglu Timucin

2009-01-01

Full Text Available Some diseases, such as Gitelman′s syndrome, Bartter′s syndrome, and primary hyperaldosteronism (Conn′s syndrome, may bear some similar clinical and laboratory findings. Their treatment modalities being different from one another, the need for a scrupulous diagnostic evaluation arises as far as clinical practice is concerned. In this report, we present a patient with Conn′s syndrome who was initially considered to have Gitelman′s syndrome due to displaying a few overlapping features of both diseases. We also give an account of the hardships encountered during the diagnostic evaluation.

Seventeen Alpha-hydroxylase Deficiency

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Siew-Lee Wong

2006-01-01

Full Text Available Seventeen a-hydroxylase deficiency (17OHD is a rare form of congenital adrenal hyperplasia in which defects in the biosynthesis of cortisol and sex steroid result in mineralocorticoid excess, hypokalemic hypertension and sexual abnormalities such as pseudohermaphroditism in males, and sexual infantilism in females. The disease is inherited in an autosomal recessive pattern, and is caused by mutations in the gene encoding cytochrome P450c17 (CYP17, which is the single polypeptide that mediates both 17α-hydroxylase and 17,20-lyase activities. We report the case of a 15-year-old patient with 17OHD who had a female phenotype but male karyotype (46,XY. The diagnosis was made based on classical clinical features, biochemical data and molecular genetic study. Two mutations were identified by polymerase chain reaction amplification and sequencing, including a S106P point mutation in exon 2 and a 9-bp (GACTCTTTC deletion from nucleotide position 1519 in exon 8 of CYP17. The first of these mutations was found in the father and the second in the mother, and both have been previously reported in Asia. The patient's hypertension and hypokalemia resolved after glucocorticoid replacement and treatment with potassium-sparing diuretics. Sex hormone replacement was prescribed for induction of sexual development and reduction of the final height. Prophylactic gonadectomy was scheduled. In summary, 17OHD should be suspected in patients with hypokalemic hypertension and lack of secondary sexual development so that appropriate therapy can be implemented.

38 CFR 3.252 - Annual income; pension; Mexican border period and later war periods.

Science.gov (United States)

2010-07-01

...; Mexican border period and later war periods. 3.252 Section 3.252 Pensions, Bonuses, and Veterans' Relief... Dependency, Income and Estate § 3.252 Annual income; pension; Mexican border period and later war periods. (a) Annual income limitations; old-law pension. Where the right to old-law pension is payable under section...

Nanopublication beyond the sciences: the PeriodO period gazetteer

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Patrick Golden

2016-02-01

Full Text Available The information expressed in humanities datasets is inextricably tied to a wider discursive environment that is irreducible to complete formal representation. Humanities scholars must wrestle with this fact when they attempt to publish or consume structured data. The practice of “nanopublication,” which originated in the e-science domain, offers a way to maintain the connection between formal representations of humanities data and its discursive basis. In this paper we describe nanopublication, its potential applicability to the humanities, and our experience curating humanities nanopublications in the PeriodO period gazetteer.

Comparison of Periodized and Non-Periodized Resistance Training on Maximal Strength: A Meta-Analysis.

Science.gov (United States)

Williams, Tyler D; Tolusso, Danilo V; Fedewa, Michael V; Esco, Michael R

2017-10-01

Periodization is a logical method of organizing training into sequential phases and cyclical time periods in order to increase the potential for achieving specific performance goals while minimizing the potential for overtraining. Periodized resistance training plans are proposed to be superior to non-periodized training plans for enhancing maximal strength. The primary aim of this study was to examine the previous literature comparing periodized resistance training plans to non-periodized resistance training plans and determine a quantitative estimate of effect on maximal strength. All studies included in the meta-analysis met the following inclusion criteria: (1) peer-reviewed publication; (2) published in English; (3) comparison of a periodized resistance training group to a non-periodized resistance training group; (4) maximal strength measured by 1-repetition maximum (1RM) squat, bench press, or leg press. Data were extracted and independently coded by two authors. Random-effects models were used to aggregate a mean effect size (ES), 95% confidence intervals (CIs) and potential moderators. The cumulative results of 81 effects gathered from 18 studies published between 1988 and 2015 indicated that the magnitude of improvement in 1RM following periodized resistance training was greater than non-periodized resistance training (ES = 0.43, 95% CI 0.27-0.58; P training status (β = -0.59; P = 0.0305), study length (β = 0.03; P = 0.0067), and training frequency (β = 0.46; P = 0.0123) were associated with a change in 1RM. These results indicate that undulating programs were more favorable for strength gains. Improvements in 1RM were greater among untrained participants. Additionally, higher training frequency and longer study length were associated with larger improvements in 1RM. These results suggest that periodized resistance training plans have a moderate effect on 1RM compared to non-periodized training plans. Variation in training stimuli

Book Reviews in Periodicals.

Science.gov (United States)

Ettelt, Harold J.

All recent issues of periodicals found which contain indexed book reviews are listed in this compilation from Drake Memorial Library at the New York State University at Brockport. The periodicals are listed by 29 subject headings in this informal guide designed to be used at Drake Library. The number of reviews in the periodical in a recent year…

17-α-Hydroxylase deficiency: An unusual case with primary amenorrhea and hypertension

Directory of Open Access Journals (Sweden)

Sunil Kumar Kota

2011-01-01

Full Text Available A 14-year-old girl presented with acute onset quadriparesis and newly detected hypertension. Parental consanguinity, delayed puberty with normal stature form the additional information. Hypokalemia with metabolic alkalosis, low cortisol, high ACTH and FSH pointed to the possibility of CAH with 17α hydroxylase deficiency. 46XX karyotype and high progesterone supported this. Normalization of hypokalemia and hypertension with glucocorticoid treatment confirmed the diagnosis. In summary, the possibility of 17 OHD should be suspected in patients with hypokalemic myopathy, Hypertension and hypogonadism so that appropriate therapy can be implemented.

Testing periodically integrated autoregressive models

NARCIS (Netherlands)

Ph.H.B.F. Franses (Philip Hans); M.J. McAleer (Michael)

1997-01-01

textabstractPeriodically integrated time series require a periodic differencing filter to remove the stochastic trend. A non-periodic integrated time series needs the first-difference filter for similar reasons. When the changing seasonal fluctuations for the non-periodic integrated series can be

Detecting periodicities with Gaussian processes

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Nicolas Durrande

2016-04-01

Full Text Available We consider the problem of detecting and quantifying the periodic component of a function given noise-corrupted observations of a limited number of input/output tuples. Our approach is based on Gaussian process regression, which provides a flexible non-parametric framework for modelling periodic data. We introduce a novel decomposition of the covariance function as the sum of periodic and aperiodic kernels. This decomposition allows for the creation of sub-models which capture the periodic nature of the signal and its complement. To quantify the periodicity of the signal, we derive a periodicity ratio which reflects the uncertainty in the fitted sub-models. Although the method can be applied to many kernels, we give a special emphasis to the Matérn family, from the expression of the reproducing kernel Hilbert space inner product to the implementation of the associated periodic kernels in a Gaussian process toolkit. The proposed method is illustrated by considering the detection of periodically expressed genes in the arabidopsis genome.

Periods and Nori motives

CERN Document Server

Huber, Annette

2017-01-01

This book casts the theory of periods of algebraic varieties in the natural setting of Madhav Nori’s abelian category of mixed motives. It develops Nori’s approach to mixed motives from scratch, thereby filling an important gap in the literature, and then explains the connection of mixed motives to periods, including a detailed account of the theory of period numbers in the sense of Kontsevich-Zagier and their structural properties. Period numbers are central to number theory and algebraic geometry, and also play an important role in other fields such as mathematical physics. There are long-standing conjectures about their transcendence properties, best understood in the language of cohomology of algebraic varieties or, more generally, motives. Readers of this book will discover that Nori’s unconditional construction of an abelian category of motives (over fields embeddable into the complex numbers) is particularly well suited for this purpose. Notably, Kontsevich's formal period algebra represents a to...

Periodic and almost periodic solutions for multi-valued differential equations in Banach spaces

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E. Hanebaly

2000-03-01

Full Text Available It is known that for $omega$-periodic differential equations of monotonous type, in uniformly convex Banach spaces, the existence of a bounded solution on ${Bbb R}^+$ is equivalent to the existence of an omega-periodic solution (see Haraux [5] and Hanebaly [7, 10]. It is also known that if the Banach space is strictly convex and the equation is almost periodic and of monotonous type, then the existence of a continuous solution with a precompact range is equivalent to the existence of an almost periodic solution (see Hanebaly [8]. In this note we want to generalize the results above for multi-valued differential equations.

Characterization of an intravenously injected bolus

International Nuclear Information System (INIS)

Samuel, A.M.; Raikar, U.R.; Atmaram, S.H.; Ganatra, R.D.

1976-01-01

A study of some parameters affecting the time activity histogram of an intravenous bolus injection of radioactivity was performed. A scoring system for bolus compactness was attempted. A score of 2 and above was considered to be a satisfactory bolus. Volumes less than 1 ml tended to result in a satisfactory bolus. The nature of radiopharmaceutical injected, different injecters and age of the patient did not affect the score. Thyrotoxic patients gave the best bolus score. (orig.) [de

Nonparametric Inference for Periodic Sequences

KAUST Repository

Sun, Ying

2012-02-01

This article proposes a nonparametric method for estimating the period and values of a periodic sequence when the data are evenly spaced in time. The period is estimated by a "leave-out-one-cycle" version of cross-validation (CV) and complements the periodogram, a widely used tool for period estimation. The CV method is computationally simple and implicitly penalizes multiples of the smallest period, leading to a "virtually" consistent estimator of integer periods. This estimator is investigated both theoretically and by simulation.We also propose a nonparametric test of the null hypothesis that the data have constantmean against the alternative that the sequence of means is periodic. Finally, our methodology is demonstrated on three well-known time series: the sunspots and lynx trapping data, and the El Niño series of sea surface temperatures. © 2012 American Statistical Association and the American Society for Quality.

Paradoxical modulation of thyrotrope responsiveness to TRH during the treatment of thyrotoxic patients: apparent absence of feed-back regulation

International Nuclear Information System (INIS)

Golstein, J.; Vanhaelst, L.; Camus, M.; Glinger, D.

1976-01-01

Eight patients with active thyrotoxicosis have been followed up to one year after the onset of antithyroid treatment. At different time intervals during the investigation period, TRH tests were performed and total T 4 and T 3 basal levels were measured. The TRH-induced TSH release was delayed in all patients in spite of a normalization of the circulating levels of thyroid hormones. The delay varied according to the patients and lasted, in some cases, for as long as 24 weeks after the normalization of the thyroid hormone levels. Administration of thyroid hormones, together with methimazole, did not seem to prevent the pituitary thyrotropes responsiveness; moreover, it did not provoke an inhibition of the TRH-induced TSH release once the thyrotropes reactivity was fully restored. The feed-back mechanism does not seem to be the main modulator of the pituitary responsiveness to TRH in these circumstances. (orig.) [de

Periodic waves in nonlinear metamaterials

International Nuclear Information System (INIS)

Liu, Wen-Jun; Xiao, Jing-Hua; Yan, Jie-Yun; Tian, Bo

2012-01-01

Periodic waves are presented in this Letter. With symbolic computation, equations for monochromatic waves are studied, and analytic periodic waves are obtained. Factors affecting properties of periodic waves are analyzed. Nonlinear metamaterials, with the continuous distribution of the dielectric permittivity obtained, are different from the ones with the discrete distribution. -- Highlights: ► Equations for the monochromatic waves in transverse magnetic polarization have been studied. ► Analytic periodic waves for the equations have been obtained. ► Periodic waves are theoretically presented and studied in the nonlinear metamaterials.

Beam-wave interaction in periodic and quasi-periodic structures. 2. ed.

International Nuclear Information System (INIS)

Schaechter, Levi

2011-01-01

The main theme of this book is the interaction of electrons with electromagnetic waves in the presence of periodic and quasi-periodic structures in vacuum, in view of applications in the design and operation of particle accelerators. The first part of the book is concerned with the textbook-like presentation of the basic material, in particular reviewing elementary electromagnetic phenomena and electron dynamics. The second part of the book describes the current models for beam-wave interactions with periodic and quasi-periodic structures. This is the basis for introducing, in the last part of the book, a number of particle and radiation sources that rest on these principles, in particular the free-electron laser, wake-field acceleration schemes and a number of other advanced particle accelerator concepts. This second edition brings this fundamental text up-to-date in view of the enormous advances that have been made over the last decade since the first edition was published. All chapters, as well as the bibliography, have been significantly revised and extended, and the number of end-of-chapter exercises has been further increased to enhance this book's usefulness for teaching specialized graduate courses. (orig.)

Optical Frequency Mixing in Periodically-Patterned and in Quasi-Periodically-Patterned Nonlinear media

International Nuclear Information System (INIS)

Arie, A.

1999-01-01

Nonlinear frequency mixing processes, e.g. second harmonic generation, sum and difference frequency generation, etc., require matching of the phases of the interacting waves. The traditional method to achieve it is by selecting a specific angle of propagation in a birefringent nonlinear crystal. The main limitation of the birefringent phase matching method stems from the fact that for many interesting interactions, the phase matching condition cannot be satisfied in a specific crystal. This obstacle can be removed by the technique of quasi-phase-matching (QPM), where the nonlinear coefficient of the material is modulated at a fixed spatial frequency that equals the wave-vector phase mismatch between the interacting waves. An important development in recent years is the ability to periodically reverse the sign of the nonlinear coefficient in ferroelectric crystals by applying a high electric field through a periodic electrode. Some recent QPM interactions in periodically-poled KTP that were recently achieved at Tel-Aviv University include continuous-wave optical parametric oscillations, as well as generation of tunable mid-infrared radiation by difference frequency generation. Periodic patterning of the nonlinear coefficient enables to phase match only a single interaction. It would be advantageous to further extend the applications of this technique in order to simultaneously satisfy several interactions on a single crystal. This cannot be usually achieved in a periodic pattern, however more sophisticated quasi-periodic structures can be designed in this case. An interesting analogy can be drawn between artificially-made quasi-periodically-patterned nonlinear crystals and quasi-crystals found in nature, in rapidly-cooled metallic alloys

Nonparametric Inference for Periodic Sequences

KAUST Repository

Sun, Ying; Hart, Jeffrey D.; Genton, Marc G.

2012-01-01

the periodogram, a widely used tool for period estimation. The CV method is computationally simple and implicitly penalizes multiples of the smallest period, leading to a "virtually" consistent estimator of integer periods. This estimator is investigated both

Acute Flaccid paralysis in adults: Our experience

Directory of Open Access Journals (Sweden)

Rupesh Kaushik

2014-01-01

Full Text Available Acute flaccid paralysis (AFP is a complex clinical syndrome with a broad array of potential etiologies that vary with age. We present our experience of acute onset lower motor neuron paralysis. Materials and Methods: One hundred and thirty-three consecutive adult patients presenting with weakness of duration less than four weeks over 12 months period were enrolled. Detailed history, clinical examination, and relevant investigations according to a pre-defined diagnostic algorithm were carried out. The patients were followed through their hospital stay till discharge or death. Results: The mean age was 33.27 (range 13-89 years with male preponderance (67.7%. The most common etiology was neuroparalytic snake envenomation (51.9%, followed by Guillain Barre syndrome (33.1%, constituting 85% of all patients. Hypokalemic paralysis (7.5% and acute intermittent porphyria (4.5% were the other important conditions. We did not encounter any case of acute polio mylitis in adults. In-hospital mortality due to respiratory paralysis was 9%. Conclusion: Neuroparalytic snakebite and Guillain Barre syndrome were the most common causes of acute flaccid paralysis in adults in our study.

Induction of painless thyroiditis in patients receiving programmed death 1 receptor immunotherapy for metastatic malignancies.

Science.gov (United States)

Orlov, Steven; Salari, Farnaz; Kashat, Lawrence; Walfish, Paul G

2015-05-01

Immunotherapies against immune checkpoints that inhibit T cell activation [cytotoxic T lymphocyte antigen 4 (CTLA-4) and programmed cell death 1 (PD-1)] are emerging and promising treatments for several metastatic malignancies. However, the precise adverse effects of these therapies on thyroid gland function have not been well described. We report on 10 cases of painless thyroiditis syndrome (PTS) from a novel etiology, following immunotherapy with anti-PD-1 monoclonal antibodies (mAb) during treatment for metastatic malignancies. Six patients presented with transient thyrotoxicosis in which thyrotropin binding inhibitory immunoglobulins (TBII) were absent for all, whereas four patients had evidence of positive antithyroid antibodies. All thyrotoxic patients required temporary beta-blocker therapy and had spontaneous resolution of thyrotoxicosis with subsequent hypothyroidism. Four patients presented with hypothyroidism without a detected preceding thyrotoxic phase, occurring 6-8 weeks after initial drug exposure. All of these patients had positive antithyroid antibodies and required thyroid hormone replacement therapy for a minimum of 6 months. Patients receiving anti-PD-1 mAb therapy should be monitored for signs and symptoms of PTS which may require supportive treatment with beta-blockers or thyroid hormone replacement. The anti-PD-1 mAb is a novel exogenous cause of PTS and provides new insight into the possible perturbations of the immune network that may modulate the development of endogenous PTS, including cases of sporadic and postpartum thyroiditis.

Periodic Table Target: A Game that Introduces the Biological Significance of Chemical Element Periodicity

Science.gov (United States)

Sevcik, Richard S.; McGinty, Ragan L.; Schultz, Linda D.; Alexander, Susan V.

2008-01-01

Periodic Table Target, a game for middle school or high school students, familiarizes students with the form of the periodic table and the biological significance of different elements. The Periodic Table Target game board is constructed as a class project, and the game is played to reinforce the content. Students are assigned several elements…

Periodic instantons and scattering amplitudes

International Nuclear Information System (INIS)

Khlebnikov, S.Yu.; Rubakov, V.A.; Tinyakov, P.G.

1991-04-01

We discuss the role of periodic euclidean solutions with two turning points and zero winding number (periodic instantons) in instanton induced processes below the sphaleron energy E sph . We find that the periodic instantons describe certain multiparticle scattering events leading to the transitions between topologically distinct vacua. Both the semiclassical amplitudes and inital and final states of these transitions are determined by the periodic instantons. Furthermore, the corresponding probabilities are maximal among all states of given energy. We show that at E ≤ E sph , the periodic instantons can be approximated by infinite chains of ordinary instantons and anti-instantons, and they naturally emerge as deformations of the zero energy instanton. In the framework of 2d abelian Higgs model and 4d electroweak theory we show, however, that there is not obvious relation between periodic instantons and two-particle scattering amplitudes. (orig.)

Corticosteroid-exacerbated symptoms in an Andersen's syndrome kindred.

Science.gov (United States)

Bendahhou, Saïd; Fournier, Emmanuel; Gallet, Serge; Ménard, Dominique; Larroque, Marie-Madeleine; Barhanin, Jacques

2007-04-15

Periodic paralysis, cardiac arrhythmia and bone features are the hallmark of Andersen's syndrome (AS), a rare disorder caused by mutations in the KCNJ2 gene that encodes for the inward rectifier K(+)-channel Kir2.1. Rest following strenuous physical activity, carbohydrate ingestion, emotional stress and exposure to cold are the precipitating triggers. Most of the mutations act in a dominant-negative fashion, either through a trafficking dysfunction or through Kir2.1-phosphatidyl inositol bisphosphate binding defect. We have identified two families that were diagnosed with periodic paralysis and cardiac abnormalities, but only discrete development features. The proband in one of the two families reported having his symptoms occurring twice within the day following corticosteroids ingestion, and alleviated after stopping the corticosteroid treatment. Electromyographic evaluations pointed out to a typical hypokalemic periodic paralysis pattern. Molecular screening of the KCNJ2 gene identified two mutations leading to C54F and T305P substitutions in the Kir2.1 protein. Functional expression in mammalian cells revealed a loss-of-function of the mutated channels and a dominant-negative effect when both mutants and wild-type channels are present in the same cell. However, channel trafficking and assembly are not affected. Substitutions at these residues may interfere with phosphatidyl inositol bisphosphate binding to Kir2.1 channels. Sensitivity of our patients to multiple corticosteroid administrations shows that care must be taken in the use of such treatments in AS patients. Taken together, our data suggest the inclusion of the KCNJ2 gene in the molecular screening of patients with periodic paralysis, even when the classical AS dysmorphic features are not present.

Rationalization of Comet Halley's periods

Science.gov (United States)

Belton, Michael J. S.

1990-01-01

The sense of long axis orientation of Comet Halley during the Vega 1 encounter must be reversed from that deduced by Sagdeev et al. (1986) in order to harmonize the comet nucleus' Vega/Giotto-observed orientations with periodicities extracted from time-series brightness data. It is also demonstrated that Vega/Giotto observations can be satisfied by either a 2.2- or 3.7-day long-axis free precession period. A novel Fourier algorithm is used to reanalyze five independent data sets; strong evidence is adduced for periods harmonically related to a 7.4-day period. The preferred candidate models for Halley's nuclear rotation are characterized by a long-axis precession period of 3.7 days.

Suppression of period-doubling and nonlinear parametric effects in periodically perturbed systems

International Nuclear Information System (INIS)

Bryant, P.; Wiesenfeld, K.

1986-01-01

We consider the effect on a generic period-doubling bifurcation of a periodic perturbation, whose frequency ω 1 is near the period-doubled frequency ω 0 /2. The perturbation is shown to always suppress the bifurcation, shifting the bifurcation point and stabilizing the behavior at the original bifurcation point. We derive an equation characterizing the response of the system to the perturbation, analysis of which reveals many interesting features of the perturbed bifurcation, including (1) the scaling law relating the shift of the bifurcation point and the amplitude of the perturbation, (2) the characteristics of the system's response as a function of bifurcation parameter, (3) parametric amplification of the perturbation signal including nonlinear effects such as gain saturation and a discontinuity in the response at a critical perturbation amplitude, (4) the effect of the detuning (ω 1 -ω 0 /2) on the bifurcation, and (5) the emergence of a closely spaced set of peaks in the response spectrum. An important application is the use of period-doubling systems as small-signal amplifiers, e.g., the superconducting Josephson parametric amplifier

Iraqi architecture in mogul period

Directory of Open Access Journals (Sweden)

Hasan Shatha

2018-01-01

Full Text Available Iraqi architecture have many periods passed through it until now, each on from these periods have it is architectural style, also through time these styles interacted among us, to creating kind of space forming, space relationships, and architectural elements (detailed treatments, the research problem being from the multi interacted architectural styles causing some of confused of general characteristic to every style, that we could distinguish by it. Research tries to study architecture style through Mogul Conquest to Baghdad. Aim of research follow main characteristic for this architectural style in the Mogul periods on the level of form, elements, and treatments. Research depending on descriptive and analytical all buildings belong to this period, so from analyzing there style by, general form for building, architectural elements, and it architectural treatment, therefore; repeating this procedures to every building we get some similarities, from these similarities we can making conclusion about pure characteristic of the style of these period. Other side, we also discover some Dissimilar in the building periods, these will lead research to make what interacting among styles in this period, after all that we can drew clearly main characteristic of Architectural Style for Mogul Conquest in Baghdad

Problem Periods

Science.gov (United States)

... ovary syndrome. Read our information on PCOS for teens , and see your doctor if you think you may have PCOS. Major weight loss. Girls who have anorexia will often stop having periods. When to see ...

Ocular myasthenia gravis in a setting of thyrotoxicosis

Directory of Open Access Journals (Sweden)

Sarabjeet Chhabra

2013-01-01

Full Text Available Ocular myasthenia gravis in conjunction with thyroid disorders, although rare, has been reported in the past. However, the similarity in the presentation of both the entities and the tendency of myasthenia gravis to get overlooked easily, even by experienced clinicians, necessitates a thorough knowledge, a strong consideration, and a vigilant approach, to aid in its diagnosis. We discuss a case of a female in a thyrotoxic state, with symptoms of ocular myasthenia gravis, and a brief overview of this entity.

Type IV neonatal Bartter syndrome complicated with congenital chloride diarrhea.

Science.gov (United States)

Sakallı, Hale; Bucak, Hakan İbrahim

2012-01-01

Pseudo-Bartter syndrome encompasses a heterogenous group of disorders similar to Bartter syndrome. Sometimes a few status may be nested, as in our case presented here. An 8-month-old boy was referred to our hospital with of intractable diarrhea, polyuria, persistent hypokalemia, abdominal distension and failure to thrive. He was born in the 34 6/7 gestational week (GW) to consanguineous parents. In the 30(th) GW polyhydramnios was verified by ultrasonography. The laboratory results showed hypokalemic-hypochloremic metabolic alkalosis, hyponatremia, and increased urinary loss of chloride, potassium and calcium. An audiogram test revealed complete sensorineural deafness. Ultrasonography revealed medullary nephrocalcinosis in both kidneys. Elevated plasma renin activity and aldosterone were found and a provisional diagnosis of type-IV neonatal Bartter syndrome was made. Treatment with indomethacin, spironolactone and additional intake of NaCl/KCl was initiated. Despite these therapies, the child's diarrhea persisted but serum potassium concentration normalized, and hypercalciuria and urine output reduced. After determining the high fecal chloride concentration, there was an immediate decompensation of the disease on indomethacin withdrawal, thus a diagnosis of type IV neonatal Bartter syndrome complicated with congenital chloride diarrhea was considered. Indomethacin, spironolactone and supplementary therapies with NaCl/KCl were continued, which resulted in the normalization of serum electrolytes as well as his physical development, but high contents of chloride in urine and faeces and nephrocalcinosis remains unchanged during 1-year follow-up. Because of the clinical and laboratory simulations between the various diseases that lead to hypokalemic-hypochloremic metabolic alkalosis, patients must be evaluated carefully.

Periodic Poisson Solver for Particle Tracking

International Nuclear Information System (INIS)

Dohlus, M.; Henning, C.

2015-05-01

A method is described to solve the Poisson problem for a three dimensional source distribution that is periodic into one direction. Perpendicular to the direction of periodicity a free space (or open) boundary is realized. In beam physics, this approach allows to calculate the space charge field of a continualized charged particle distribution with periodic pattern. The method is based on a particle mesh approach with equidistant grid and fast convolution with a Green's function. The periodic approach uses only one period of the source distribution, but a periodic extension of the Green's function. The approach is numerically efficient and allows the investigation of periodic- and pseudo-periodic structures with period lengths that are small compared to the source dimensions, for instance of laser modulated beams or of the evolution of micro bunch structures. Applications for laser modulated beams are given.

Holonomic systems for period mappings

Energy Technology Data Exchange (ETDEWEB)

Chen, Jingyue, E-mail: jychen@brandeis.edu [Department of Mathematics, Brandeis University, Waltham, MA 02454 (United States); Huang, An, E-mail: anhuang@math.harvard.edu [Department of Mathematics, Harvard University, Cambridge, MA 02138 (United States); Lian, Bong H., E-mail: lian@brandeis.edu [Department of Mathematics, Brandeis University, Waltham, MA 02454 (United States)

2015-09-15

Period mappings were introduced in the sixties [4] to study variation of complex structures of families of algebraic varieties. The theory of tautological systems was introduced recently [7,8] to understand period integrals of algebraic manifolds. In this paper, we give an explicit construction of a tautological system for each component of a period mapping. We also show that the D-module associated with the tautological system gives rise to many interesting vanishing conditions for period integrals at certain special points of the parameter space.

39 CFR 121.2 - Periodicals.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Periodicals. 121.2 Section 121.2 Postal Service UNITED STATES POSTAL SERVICE POST OFFICE SERVICES [DOMESTIC MAIL] SERVICE STANDARDS FOR MARKET-DOMINANT MAIL PRODUCTS § 121.2 Periodicals. (a) End-to-End. (1) For all SCF turnaround Periodicals properly...

On some periodicity effects

DEFF Research Database (Denmark)

Sorokin, Sergey V.

2015-01-01

The talk is concerned with the modelling of wave propagation in and vibration of periodic elastic structures. Although analysis of wave-guide properties of infinite periodic structures is a well establish research subject, some issues have not yet been fully addressed in the literature. The aim o...

Periodically poled silicon

Science.gov (United States)

Hon, Nick K.; Tsia, Kevin K.; Solli, Daniel R.; Khurgin, Jacob B.; Jalali, Bahram

2010-02-01

Bulk centrosymmetric silicon lacks second-order optical nonlinearity χ(2) - a foundational component of nonlinear optics. Here, we propose a new class of photonic device which enables χ(2) as well as quasi-phase matching based on periodic stress fields in silicon - periodically-poled silicon (PePSi). This concept adds the periodic poling capability to silicon photonics, and allows the excellent crystal quality and advanced manufacturing capabilities of silicon to be harnessed for devices based on χ(2)) effects. The concept can also be simply achieved by having periodic arrangement of stressed thin films along a silicon waveguide. As an example of the utility, we present simulations showing that mid-wave infrared radiation can be efficiently generated through difference frequency generation from near-infrared with a conversion efficiency of 50% based on χ(2) values measurements for strained silicon reported in the literature [Jacobson et al. Nature 441, 199 (2006)]. The use of PePSi for frequency conversion can also be extended to terahertz generation. With integrated piezoelectric material, dynamically control of χ(2)nonlinearity in PePSi waveguide may also be achieved. The successful realization of PePSi based devices depends on the strength of the stress induced χ(2) in silicon. Presently, there exists a significant discrepancy in the literature between the theoretical and experimentally measured values. We present a simple theoretical model that produces result consistent with prior theoretical works and use this model to identify possible reasons for this discrepancy.

Unsuspected Clenbuterol Toxicity in a Patient Using Intramuscular Testosterone

Directory of Open Access Journals (Sweden)

Matthew K. Griswold

2017-05-01

Full Text Available Clenbuterol is a beta-agonist that has been abused by fitness-oriented individuals for muscle growth and weight loss. We report a case of a 46-year-old man who presented tachycardic, hypokalemic, and hyperglycemic after injecting testosterone obtained from Brazil. He developed refractory hypotension and was started on an esmolol infusion for suspected beta-agonist toxicity. Laboratory analysis showed a detectable clenbuterol serum concentration. Analysis of an unopened ampule contained boldenone undecylenate, clenbuterol, and vitamin E. This case illustrates a novel exposure that caused beta-agonist toxicity and was treated successfully with rapid-onset beta blocker.

Gitelman′s syndrome with panhypopituitarism: Reno-endocrine interplay

Directory of Open Access Journals (Sweden)

Vimal Upreti

2012-01-01

Full Text Available Gitelman′s syndrome is an inherited tubulopathy affecting thiazide-sensitive sodium chloride cotransporter, which manifests with hypokalemic alkalosis, hypomagnesemia, and hypocalciuria. Recently few cases have been described having an association of Gitelman′s syndrome with pituitary abnormalities on imaging, though with normal hormonal status. We describe the first case of an adult patient having Gitelman′s syndrome and hypopituitarism with abnormal pituitary imaging. She presented to us with hypotension, hypokalemia, hypomagnesemia with alkalosis, hypothyroidism, hypocortisolism, and hypogonadism. She was treated with replacement of electrolytes and hormones, to which she showed an excellent response.

Periodic precursors of nonlinear dynamical transitions

International Nuclear Information System (INIS)

Jiang Yu; Dong Shihai; Lozada-Cassou, M.

2004-01-01

We study the resonant response of a nonlinear system to external periodic perturbations. We show by numerical simulation that the periodic resonance curve may anticipate the dynamical instability of the unperturbed nonlinear periodic system, at parameter values far away from the bifurcation points. In the presence of noise, the buried intrinsic periodic dynamics can be picked out by analyzing the system's response to periodic modulation of appropriate intensity

Handgun waiting periods reduce gun deaths.

Science.gov (United States)

Luca, Michael; Malhotra, Deepak; Poliquin, Christopher

2017-11-14

Handgun waiting periods are laws that impose a delay between the initiation of a purchase and final acquisition of a firearm. We show that waiting periods, which create a "cooling off" period among buyers, significantly reduce the incidence of gun violence. We estimate the impact of waiting periods on gun deaths, exploiting all changes to state-level policies in the Unites States since 1970. We find that waiting periods reduce gun homicides by roughly 17%. We provide further support for the causal impact of waiting periods on homicides by exploiting a natural experiment resulting from a federal law in 1994 that imposed a temporary waiting period on a subset of states. Copyright © 2017 the Author(s). Published by PNAS.

Long-Period Variability in o Ceti

Science.gov (United States)

Templeton, Matthew R.; Karovska, Margarita

2009-02-01

We carried out a new and sensitive search for long-period variability in the prototype of the Mira class of long-period pulsating variables, o Ceti (Mira A), the closest and brightest Mira variable. We conducted this search using an unbroken light curve from 1902 to the present, assembled from the visual data archives of five major variable star observing organizations from around the world. We applied several time-series analysis techniques to search for two specific kinds of variability: long secondary periods (LSPs) longer than the dominant pulsation period of ~333 days, and long-term period variation in the dominant pulsation period itself. The data quality is sufficient to detect coherent periodic variations with photometric amplitudes of 0.05 mag or less. We do not find evidence for coherent LSPs in o Ceti to a limit of 0.1 mag, where the amplitude limit is set by intrinsic, stochastic, low-frequency variability of approximately 0.1 mag. We marginally detect a slight modulation of the pulsation period similar in timescale to that observed in the Miras with meandering periods, but with a much lower period amplitude of ±2 days. However, we do find clear evidence of a low-frequency power-law component in the Fourier spectrum of o Ceti's long-term light curve. The amplitude of this stochastic variability is approximately 0.1 mag at a period of 1000 days, and it exhibits a turnover for periods longer than this. This spectrum is similar to the red noise spectra observed in red supergiants.

Estimates on the minimal period for periodic solutions of nonlinear second order Hamiltonian systems

International Nuclear Information System (INIS)

Yiming Long.

1994-11-01

In this paper, we prove a sharper estimate on the minimal period for periodic solutions of autonomous second order Hamiltonian systems under precisely Rabinowitz' superquadratic condition. (author). 20 refs, 1 fig

Depression in pregnancy and postpartum period.

Science.gov (United States)

Sood, Mamta; Sood, A K

2003-01-01

This prospective study was carried out in a service hospital, with the aim to study the prevalence and incidence of depression in pregnancy and postpartum period. Eighty Four consecutive patients attending the antenatal outpatient in the Obstetrics & Gynaecology department in their last trimester of pregnancy were recruited for the study. They were assessed on Beck Depression Inventory thrice viz. during third trimester of pregnancy, within 3 days of delivery (early postpartum period) & within 4-8 weeks of delivery (late postpartum period).The prevalence of depression was 8.3%, 20% and 12.8% respectively at three ratings. The incidence was 16% and 10% in the early & late postpartum period respectively. Further analysis revealed that depression in pregnancy correlated significantly with depression in early postpartum period, but not with late postpartum period. Depression in early postpartum period correlated with depression in late postpartum period.These findings have implications for early detection and care of women at risk for developing depression.

Periodic solutions of nonlinear vibrating beams

Directory of Open Access Journals (Sweden)

J. Berkovits

2003-01-01

Full Text Available The aim of this paper is to prove new existence and multiplicity results for periodic semilinear beam equation with a nonlinear time-independent perturbation in case the period is not prescribed. Since the spectrum of the linear part varies with the period, the solvability of the equation depends crucially on the period which can be chosen as a free parameter. Since the period of the external forcing is generally unknown a priori, we consider the following natural problem. For a given time-independent nonlinearity, find periods T for which the equation is solvable for any T-periodic forcing. We will also deal with the existence of multiple solutions when the nonlinearity interacts with the spectrum of the linear part. We show that under certain conditions multiple solutions do exist for any small forcing term with suitable period T. The results are obtained via generalized Leray-Schauder degree and reductions to invariant subspaces.

The Living Periodic Table

Science.gov (United States)

Nahlik, Mary Schrodt

2005-01-01

To help make the abstract world of chemistry more concrete eighth-grade students, the author has them create a living periodic table that can be displayed in the classroom or hallway. This display includes information about the elements arranged in the traditional periodic table format, but also includes visual real-world representations of the…

Orbital periods of recurrent novae

International Nuclear Information System (INIS)

Schaefer, B.E.

1990-01-01

The class of recurrent novae (RN) with thermonuclear runaways contains only three systems (T Pyx, U Sco, and V394 CrA), for which no orbital periods are known. This paper presents a series of photometric observations where the orbital periods for all three systems are discovered. T Pyx is found to have sinusoidal modulation with an amplitude of 0.08 mag and a period of 2.3783 h (with a possible alias of 2.6403 h). U Sco is found to be an eclipsing system with an eclipse amplitude of roughly 1.5 mag and an orbital period of 1.2344 days. V394 CrA is found to have sinusoidal modulation with an amplitude of 0.5 mag and a period of 0.7577 days. Thus two out of three RN with thermonuclear runaways (or five out of six for all RN) have evolved companions. 16 refs

Microprocessor controlled digital period meter

International Nuclear Information System (INIS)

Keefe, D.J.; McDowell, W.P.; Rusch, G.K.

1980-01-01

A microprocessor controlled digital period meter has been developed and tested operationally on a reactor at Argonne National Laboratory. The principle of operation is the mathematical relationship between asymptotic periods and pulse counting circuitry. This relationship is used to calculate and display the reactor periods over a range of /plus or minus/1 second to /plus or minus/999 seconds. The time interval required to update each measurement automatically varies from 8 seconds at the lowest counting rates to 2 seconds at higher counting rates. The paper will describe hardware and software design details and show the advantages of this type of Period Meter over the conventional circuits. 1 ref

Dual-component model of respiratory motion based on the periodic autoregressive moving average (periodic ARMA) method

International Nuclear Information System (INIS)

McCall, K C; Jeraj, R

2007-01-01

A new approach to the problem of modelling and predicting respiration motion has been implemented. This is a dual-component model, which describes the respiration motion as a non-periodic time series superimposed onto a periodic waveform. A periodic autoregressive moving average algorithm has been used to define a mathematical model of the periodic and non-periodic components of the respiration motion. The periodic components of the motion were found by projecting multiple inhale-exhale cycles onto a common subspace. The component of the respiration signal that is left after removing this periodicity is a partially autocorrelated time series and was modelled as an autoregressive moving average (ARMA) process. The accuracy of the periodic ARMA model with respect to fluctuation in amplitude and variation in length of cycles has been assessed. A respiration phantom was developed to simulate the inter-cycle variations seen in free-breathing and coached respiration patterns. At ±14% variability in cycle length and maximum amplitude of motion, the prediction errors were 4.8% of the total motion extent for a 0.5 s ahead prediction, and 9.4% at 1.0 s lag. The prediction errors increased to 11.6% at 0.5 s and 21.6% at 1.0 s when the respiration pattern had ±34% variations in both these parameters. Our results have shown that the accuracy of the periodic ARMA model is more strongly dependent on the variations in cycle length than the amplitude of the respiration cycles

Quantized gauge invariant periodic TDHF solutions

International Nuclear Information System (INIS)

Kan, K.-K.; Griffin, J.J.; Lichtner, P.C.; Dworzecka, M.

1979-01-01

Time-dependent Hartree-Fock (TDHF) is used to study steady state large amplitude nuclear collective motions, such as vibration and rotation. As is well known the small amplitude TDHF leads to the RPA equation. The analysis of periodicity in TDHF is not trivial because TDHF is a nonlinear theory and it is not known under what circumstances a nonlinear theory can support periodic solutions. It is also unknown whether such periodic solution, if they exist, form a continuous or a discrete set. But, these properties may be important in obtaining the energy spectrum of the collective states from the TDHF description. The periodicity and Gauge Invariant Periodicity of solutions are investigated for that class of models whose TDHF solutions depend on time through two parameters. In such models TDHF supports a continuous family of periodic solutions, but only a discrete subset of these is gauge invariant. These discrete Gauge Invariant Periodic solutions obey the Bohr-Summerfeld quantization rule. The energy spectrum of the Gauge Invariant Periodic solutions is compared with the exact eigenergies in one specific example

Apathetic thyrotoxicosis.

Science.gov (United States)

Feroze, M; May, H

1997-01-01

A previously fit 37-year-old woman was admitted with acute left ventricular failure, atrial fibrillation and a left-sided thromboembolic stroke. Her ventricular rate progressively increased despite full digitalisation. She had a cardiac arrest and was successfully resuscitated. Investigations revealed evidence of hyperthyroidism and she was treated for thyrotoxic crisis. She has made a complete recovery from the hemiparesis and is now in sinus rhythm. She denied any symptoms of hyperthyroidism. This patient had apathetic thyroid crisis, which is exceedingly rare in the young.

Periodic and quasiperiodic revivals in periodically driven interacting quantum systems

Science.gov (United States)

Luitz, David J.; Lazarides, Achilleas; Bar Lev, Yevgeny

2018-01-01

Recently it has been shown that interparticle interactions generically destroy dynamical localization in periodically driven systems, resulting in diffusive transport and heating. In this Rapid Communication we rigorously construct a family of interacting driven systems which are dynamically localized and effectively decoupled from the external driving potential. We show that these systems exhibit tunable periodic or quasiperiodic revivals of the many-body wave function and thus of all physical observables. By numerically examining spinless fermions on a one-dimensional lattice we show that the analytically obtained revivals of such systems remain stable for finite systems with open boundary conditions while having a finite lifetime in the presence of static spatial disorder. We find this lifetime to be inversely proportional to the disorder strength.

Discrete symmetries in periodic-orbit theory

International Nuclear Information System (INIS)

Robbins, J.M.

1989-01-01

The application of periodic-orbit theory to systems which possess a discrete symmetry is considered. A semiclassical expression for the symmetry-projected Green's function is obtained; it involves a sum over classical periodic orbits on a symmetry-reduced phase space, weighted by characters of the symmetry group. These periodic orbits correspond to trajectories on the full phase space which are not necessarily periodic, but whose end points are related by symmetry. If the symmetry-projected Green's functions are summed, the contributions of the unperiodic orbits cancel, and one recovers the usual periodic-orbit sum for the full Green's function. Several examples are considered, including the stadium billiard, a particle in a periodic potential, the Sinai billiard, the quartic oscillator, and the rotational spectrum of SF 6

Magnetospheric Truncation, Tidal Inspiral, and the Creation of Short-period and Ultra-short-period Planets

Energy Technology Data Exchange (ETDEWEB)

Lee, Eve J.; Chiang, Eugene, E-mail: evelee@berkeley.edu [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

2017-06-10

Sub-Neptunes around FGKM dwarfs are evenly distributed in log orbital period down to ∼10 days, but dwindle in number at shorter periods. Both the break at ∼10 days and the slope of the occurrence rate down to ∼1 day can be attributed to the truncation of protoplanetary disks by their host star magnetospheres at corotation. We demonstrate this by deriving planet occurrence rate profiles from empirical distributions of pre-main-sequence stellar rotation periods. Observed profiles are better reproduced when planets are distributed randomly in disks—as might be expected if planets formed in situ—rather than piled up near disk edges, as would be the case if they migrated in by disk torques. Planets can be brought from disk edges to ultra-short (<1 day) periods by asynchronous equilibrium tides raised on their stars. Tidal migration can account for how ultra-short-period planets are more widely spaced than their longer-period counterparts. Our picture provides a starting point for understanding why the sub-Neptune population drops at ∼10 days regardless of whether the host star is of type FGK or early M. We predict planet occurrence rates around A stars to also break at short periods, but at ∼1 day instead of ∼10 days because A stars rotate faster than stars with lower masses (this prediction presumes that the planetesimal building blocks of planets can drift inside the dust sublimation radius).

Magnetospheric Truncation, Tidal Inspiral, and the Creation of Short-period and Ultra-short-period Planets

International Nuclear Information System (INIS)

Lee, Eve J.; Chiang, Eugene

2017-01-01

Sub-Neptunes around FGKM dwarfs are evenly distributed in log orbital period down to ∼10 days, but dwindle in number at shorter periods. Both the break at ∼10 days and the slope of the occurrence rate down to ∼1 day can be attributed to the truncation of protoplanetary disks by their host star magnetospheres at corotation. We demonstrate this by deriving planet occurrence rate profiles from empirical distributions of pre-main-sequence stellar rotation periods. Observed profiles are better reproduced when planets are distributed randomly in disks—as might be expected if planets formed in situ—rather than piled up near disk edges, as would be the case if they migrated in by disk torques. Planets can be brought from disk edges to ultra-short (<1 day) periods by asynchronous equilibrium tides raised on their stars. Tidal migration can account for how ultra-short-period planets are more widely spaced than their longer-period counterparts. Our picture provides a starting point for understanding why the sub-Neptune population drops at ∼10 days regardless of whether the host star is of type FGK or early M. We predict planet occurrence rates around A stars to also break at short periods, but at ∼1 day instead of ∼10 days because A stars rotate faster than stars with lower masses (this prediction presumes that the planetesimal building blocks of planets can drift inside the dust sublimation radius).

A highly specific test for periodicity

International Nuclear Information System (INIS)

Ansmann, Gerrit

2015-01-01

We present a method that allows to distinguish between nearly periodic and strictly periodic time series. To this purpose, we employ a conservative criterion for periodicity, namely, that the time series can be interpolated by a periodic function whose local extrema are also present in the time series. Our method is intended for the analysis of time series generated by deterministic time-continuous dynamical systems, where it can help telling periodic dynamics from chaotic or transient ones. We empirically investigate our method's performance and compare it to an approach based on marker events (or Poincaré sections). We demonstrate that our method is capable of detecting small deviations from periodicity and outperforms the marker-event-based approach in typical situations. Our method requires no adjustment of parameters to the individual time series, yields the period length with a precision that exceeds the sampling rate, and its runtime grows asymptotically linear with the length of the time series

A highly specific test for periodicity

Energy Technology Data Exchange (ETDEWEB)

Ansmann, Gerrit, E-mail: gansmann@uni-bonn.de [Department of Epileptology, University of Bonn, Sigmund-Freud-Straße 25, 53105 Bonn (Germany); Helmholtz Institute for Radiation and Nuclear Physics, University of Bonn, Nussallee 14–16, 53115 Bonn (Germany); Interdisciplinary Center for Complex Systems, University of Bonn, Brühler Straße 7, 53175 Bonn (Germany)

2015-11-15

We present a method that allows to distinguish between nearly periodic and strictly periodic time series. To this purpose, we employ a conservative criterion for periodicity, namely, that the time series can be interpolated by a periodic function whose local extrema are also present in the time series. Our method is intended for the analysis of time series generated by deterministic time-continuous dynamical systems, where it can help telling periodic dynamics from chaotic or transient ones. We empirically investigate our method's performance and compare it to an approach based on marker events (or Poincaré sections). We demonstrate that our method is capable of detecting small deviations from periodicity and outperforms the marker-event-based approach in typical situations. Our method requires no adjustment of parameters to the individual time series, yields the period length with a precision that exceeds the sampling rate, and its runtime grows asymptotically linear with the length of the time series.

Astrophysical implications of periodicity

International Nuclear Information System (INIS)

Muller, R.A.

1988-01-01

Two remarkable discoveries of the last decade have profound implications for astrophysics and for geophysics. These are the discovery by Alvarez et al., that certain mass extinctions are caused by the impact on the earth of a large asteroid or comet, and the discovery by Raup and Sepkoski that such extinctions are periodic, with a cycle time of 26 to 30 million years. The validity of both of these discoveries is assumed and the implications are examined. Most of the phenomena described depend not on periodicity, but just on the weaker assumption that the impacts on the earth take place primarily in showers. Proposed explanations for the periodicity include galactic oscillations, the Planet X model, and the possibility of Nemesis, a solar companion star. These hypotheses are critically examined. Results of the search for the solar companion are reported. The Deccan flood basalts of India have been proposed as the impact site for the Cretaceous impact, but this hypotheisis is in contradiction with the conclusion of Courtillot et al., that the magma flow began during a period of normal magnetic field. A possible resolution of this contradiction is proposed

Supersymmetrically transformed periodic potentials

OpenAIRE

C, David J. Fernandez

2003-01-01

The higher order supersymmetric partners of a stationary periodic potential are studied. The transformation functions associated to the band edges do not change the spectral structure. However, when the transformation is implemented for factorization energies inside of the forbidden bands, the final potential will have again the initial band structure but it can have bound states encrusted into the gaps, giving place to localized periodicity defects.

Periodic testing in operative action

International Nuclear Information System (INIS)

Larm, T.

2005-01-01

Periodic testing forms a remarkable part of the regular work tasks of the shift crew. Testing is generally carried out beside the daily monitoring and control work. Even remarkable plant related differences may occur in the procedures and routines used in periodic testing. The goal is still always the same, to regularly ensure that the systems and equipment are in working order according to their design. This presentation studies with examples the execution and scope of periodic testing as well as the routines and procedures used in the testing in Loviisa power plant. The presentation is based on the testing procedures of Loviisa power plant and the aim is not to compare them to the procedures of other plants. The scope of periodic testing has increased and the routines and procedures have been developed as the operation experience has increased. The assessment of the need of periodic testing and the consideration of the practical execution possibilities should be a part of the plant's planning phase as a part of the planning process. (orig.)

The redoubtable ecological periodic table

Science.gov (United States)

Ecological periodic tables are repositories of reliable information on quantitative, predictably recurring (periodic) habitat–community patterns and their uncertainty, scaling and transferability. Their reliability derives from their grounding in sound ecological principle...

Positive periodic solutions of periodic neutral Lotka-Volterra system with distributed delays

International Nuclear Information System (INIS)

Li Yongkun

2008-01-01

By using a fixed point theorem of strict-set-contraction, some criteria are established for the existence of positive periodic solutions of the following periodic neutral Lotka-Volterra system with distributed delays (dx i (t))/(dt) =x i (t)[a i (t)-Σ j=1 n b ij (t)∫ -T ij 0 K ij (θ)x j ( t+θ)dθ-Σ j=1 n c ij (t)∫ -T ij 0 K ij (θ) x j ' (t+θ)dθ],i=1,2,...,n, where a i ,b ij ,c ij element of C(R,R + ) (i, j = 1, 2, ..., n) are ω-periodic functions, T ij ,T ij element of (0,∞) (i, j = 1, 2, ..., n) and K ij ,K ij element of (R,R + ) satisfying ∫ -T ij 0 K ij (θ)dθ=1,∫ -T ij 0 K ij (θ)dθ=1, i, j = 1, 2, ..., n

Painful menstrual periods

Science.gov (United States)

Menstruation - painful; Dysmenorrhea; Periods - painful; Cramps - menstrual; Menstrual cramps ... into two groups, depending on the cause: Primary dysmenorrhea Secondary dysmenorrhea Primary dysmenorrhea is menstrual pain that ...

Influence of antithyroid medication on effective half-life and uptake of 131 I following radioiodine therapy

International Nuclear Information System (INIS)

Moka, D.; Voth, E.; Schicha, H.

1997-01-01

Aim: A radioiodine therapy (RIT) in thyrotoxic patients receiving antithyroid drugs (ATD) leads in comparison to nonpretreated patients either to higher therapeutic doses or to higher treatment failure rates. Aim of this study was to optimize the effect of RIT in patients pretreated with ATD. Methods: Therefore, the influence of ATD was assessed in 109 patients with shortened effective half-life of 131 I. RIT was performed under stationary conditions. Radioiodine activity of the thyroid gland was stopped three days after RIT. The patients antithyroid medication was stopped three days after RIT. The progress of the first RIT and of a second radioiodine application, which still was necessary in 29 patients, was compared to 32 patients receiving ATD, continuously. Results: Values of effective half-life for 131 I rose significantly from 3.2±0.2 to 5.7±0.2 days (Graves' disease: 3.4 to 5.7 days; toxic goiters' disease: Multifocal autonomy 3.2 to 6.2 days; unifocal autonomy 2.5 auf 5.0 days) 2-3 days after stopping ATD. There was an increase of the 131 I-uptake of a second RIT decreased significantly in patients receiving ATD, continuously. Conclusion: Effective half-life and uptake of 131 I was affected significantly by ATD. The stop taking of ATD after RIT is useful to improve an apparent insufficient RIT in thyrotoxic patients receiving ATD. (orig.) [de

Quasi-periodic synchronisation of self-modulation oscillations in a ring chip laser by an external periodic signal

International Nuclear Information System (INIS)

Aulova, T V; Kravtsov, Nikolai V; Lariontsev, E G; Chekina, S N

2011-01-01

The synchronisation of periodic self-modulation oscillations in a ring Nd:YAG chip laser under an external periodic signal modulating the pump power has been experimentally investigated. A new quasi-periodic regime of synchronisation of self-modulation oscillations is found. The characteristic features of the behaviour of spectral and temporal structures of synchronised quasi-periodic oscillations with a change in the external signal frequency are studied. (control of laser radiation parameters)

Periodization of the early postnatal development in the rat with particular attention to the weaning period

Czech Academy of Sciences Publication Activity Database

Ošťádalová, Ivana; Babický, A.

2012-01-01

Roč. 61, Suppl.1 (2012), S1-S7 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) 1M0510; GA ČR(CZ) GAP303/12/1162 Institutional research plan: CEZ:AV0Z50110509 Keywords : rat * ontogenic development * presuckling period * suckling period * weaning period Subject RIV: ED - Physiology Impact factor: 1.531, year: 2012

Manipulating the Cellular Circadian Period of Arginine Vasopressin Neurons Alters the Behavioral Circadian Period.

Science.gov (United States)

Mieda, Michihiro; Okamoto, Hitoshi; Sakurai, Takeshi

2016-09-26

As the central pacemaker in mammals, the circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus is a heterogeneous structure consisting of multiple types of GABAergic neurons with distinct chemical identities [1, 2]. Although individual cells have a cellular clock driven by autoregulatory transcriptional/translational feedback loops of clock genes, interneuronal communication among SCN clock neurons is likely essential for the SCN to generate a highly robust, coherent circadian rhythm [1]. However, neuronal mechanisms that determine circadian period length remain unclear. The SCN is composed of two subdivisions: a ventral core region containing vasoactive intestinal peptide (VIP)-producing neurons and a dorsal shell region characterized by arginine vasopressin (AVP)-producing neurons. Here we examined whether AVP neurons act as pacemaker cells that regulate the circadian period of behavior rhythm in mice. The deletion of casein kinase 1 delta (CK1δ) specific to AVP neurons, which was expected to lengthen the period of cellular clocks [3-6], lengthened the free-running period of circadian behavior as well. Conversely, the overexpression of CK1δ specific to SCN AVP neurons shortened the free-running period. PER2::LUC imaging in slices confirmed that cellular circadian periods of the SCN shell were lengthened in mice without CK1δ in AVP neurons. Thus, AVP neurons may be an essential component of circadian pacemaker cells in the SCN. Remarkably, the alteration of the shell-core phase relationship in the SCN of these mice did not impair the generation per se of circadian behavior rhythm, thereby underscoring the robustness of the SCN network. Copyright © 2016 Elsevier Ltd. All rights reserved.

Special Features In Turbulent Mixing. Comparison between Periodic and Non Periodic Case

Directory of Open Access Journals (Sweden)

Mihai Costescu

2006-12-01

Full Text Available After hundreds of years of stability study, the problems of flow kinematics are far from complete solving. A modern theory appears in this field: the mixing theory. Its mathematical methods and techniques developed the significant relation between turbulence and chaos. The turbulence is an important feature of dynamic systems with few freedom degrees, the so-called far from equilibrium systems. These are widespread between the models of excitable media.Studying a mixing for a flow implies the analysis of successive stretching and folding phenomena for its particles, the influence of parameters and initial conditions. In the previous works, the study of the 3D non-periodic models exhibited a quite complicated behavior, involving some significant events - the so-called rare events. The variation of parameters had a great influence on the length and surface deformations. The 2D (periodic case is simpler, but significant events can also issue for irrational values of the length and surface versors, as was the situation in 3D case.The comparison between 2D and 3D case revealed interesting properties; therefore a modified 2D (periodic model is tested. The numerical simulations were realized in MapleVI, for searching special mathematical events. Continuing this work both from analytical and numeric standpoint would relieve useful properties for the turbulent mixing. A proximal target is to test some special functions for the periodic model, and to study the behavior of the structures realized by the model.

Periodic variations of cosmic ray intensity with period of -37 minute observed on April 25th, 1984

International Nuclear Information System (INIS)

Sakai, Takasuke; Kato, Masahito; Takei, Ryoji; Tamai, Eiji

1985-01-01

Existence of cosmic ray variation with period ranging from a few hours to seconds during geomagnetically quiet and perturb period at different altitude with different detector, was reported previously. As short period variation is thought to be transient with small amplitude fluctuation, consequently high counting rate of cosmic ray and appropriate method for finding short periodicity, is required. Further, there is similar phenomenon in which short variation, followed by storm sudden commencement (SSC) and/or Forbush decrease (FD) occurs. In 1979, Kato et al. used 3 minutes data at Mt. Norikura and obtained -6 x 10 5 count/min, and tried to find out short periodicity of cosmic ray around SSC, but no clear conclusion was obtained. T. Sakai, et al., used plastic scintillation counter of Akeno observatory, following their preceding work. The counter has an area about 154 m 2 . High counting rate of -2 x 10 6 counts/min. was observed at Akeno which revealed the existence of -37 minute periodical oscillation with an amplitude of 0.1 % in p-p during the time period of 1300 - 1900 UT on April 25th 1984, one day before FD. Observed periodical oscillation of cosmic ray counting rate may be the result of the changes in magnetic field. But, it must be noted that there remains possibility of oscillation of cosmic ray intensity in the interplanetary space during the period, independent of geomagnetic field. (author)

Periodic-cylinder vesicle with minimal energy

International Nuclear Information System (INIS)

Xiao-Hua, Zhou

2010-01-01

We give some details about the periodic cylindrical solution found by Zhang and Ou-Yang in [1996 Phys. Rev. E 53 4206] for the general shape equation of vesicle. Three different kinds of periodic cylindrical surfaces and a special closed cylindrical surface are obtained. Using the elliptic functions contained in mathematic, we find that this periodic shape has the minimal total energy for one period when the period–amplitude ratio β ≈ 1.477, and point out that it is a discontinuous deformation between plane and this periodic shape. Our results also are suitable for DNA and multi-walled carbon nanotubes (MWNTs). (cross-disciplinary physics and related areas of science and technology)

47 CFR 22.1035 - Construction period.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Construction period. 22.1035 Section 22.1035 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Offshore Radiotelephone Service § 22.1035 Construction period. The construction period (see § 22.142) for...

Periodic Properties and Inquiry: Student Mental Models Observed during a Periodic Table Puzzle Activity

Science.gov (United States)

Larson, Kathleen G.; Long, George R.; Briggs, Michael W.

2012-01-01

The mental models of both novice and advanced chemistry students were observed while the students performed a periodic table activity. The mental model framework seems to be an effective way of analyzing student behavior during learning activities. The analysis suggests that students do not recognize periodic trends through the examination of…

Seismic isolation of two dimensional periodic foundations

International Nuclear Information System (INIS)

Yan, Y.; Mo, Y. L.; Laskar, A.; Cheng, Z.; Shi, Z.; Menq, F.; Tang, Y.

2014-01-01

Phononic crystal is now used to control acoustic waves. When the crystal goes to a larger scale, it is called periodic structure. The band gaps of the periodic structure can be reduced to range from 0.5 Hz to 50 Hz. Therefore, the periodic structure has potential applications in seismic wave reflection. In civil engineering, the periodic structure can be served as the foundation of upper structure. This type of foundation consisting of periodic structure is called periodic foundation. When the frequency of seismic waves falls into the band gaps of the periodic foundation, the seismic wave can be blocked. Field experiments of a scaled two dimensional (2D) periodic foundation with an upper structure were conducted to verify the band gap effects. Test results showed the 2D periodic foundation can effectively reduce the response of the upper structure for excitations with frequencies within the frequency band gaps. When the experimental and the finite element analysis results are compared, they agree well with each other, indicating that 2D periodic foundation is a feasible way of reducing seismic vibrations.

Period, Place and Mental Space: Using Historical Scholarship to Develop Year 7 Pupils' Sense of Period

Science.gov (United States)

Smith, Dan

2014-01-01

What is a sense of period? And how can pupils' sense of period be developed? Questions such as these have troubled history teachers for many years, often revolving around debates over the role played by empathy and imagination in coming to know a period on its own terms. Rather than adopt a comparative approach, Dan Smiths decided in his teaching…

Transient thyrotoxicosis from thyroiditis induced by sibutramine overdose: a case report.

Science.gov (United States)

Kim, S K; Lee, S M; Yoo, S S; Hahm, J R; Jung, J H; Kim, H S; Kim, S; Chung, S I; Jung, T S

2013-08-01

Sibutramine is an antiobesity drug that inhibits the reuptake of serotonin and noradrenalin in the hypothalamus. A 37-year-old Korean man presented to the emergency room for the oral intake of 280 mg of sibutramine. The patient was in thyrotoxic state. The (99m)Technetium-pertechnetate thyroid scan showed irregular uptake of radioisotope and thyroid-stimulating hormone receptor antibody and thyroperoxidase antibody were negative. Thyroid function normalized after that. The patient had transient thyrotoxicosis with thyroiditis. We report a case of thyrotoxicosis accompanied by thyroiditis resulting from the intentional overdose of sibutramine.

Weight loss and severe jaundice in a patient with hyperthyroidism.

Science.gov (United States)

Breidert, M; Offensperger, S; Blum, H E; Fischer, R

2011-09-01

Thyrotoxicosis may significantly alter hepatic function and is associated with autoimmune disorders of the liver. We report the case of a thyrotoxic patient with Graves' disease and histologically established cholestatic hepatitis. Medical treatment of hyperthyroidism normalized liver function tests. In patients with elevated liver function parameters and jaundice of unknown origin, thyroid function should generally be tested. Moreover, medical treatment of hyperthyroidism with thyrostatics may cause severe hepatitis whereas untreated hyperthyroid patients are at risk of developing chronic liver failure. © Georg Thieme Verlag KG Stuttgart · New York.

Gene Expression Profiling in the Pituitary Gland of Laying Period and Ceased Period Huoyan Geese

Directory of Open Access Journals (Sweden)

Xinhong Luan

2013-07-01

Full Text Available Huoyan goose is a Chinese local breed famous for its higher laying performance, but the problems of variety degeneration have emerged recently, especially a decrease in the number of eggs laid. In order to better understand the molecular mechanism that underlies egg laying in Huoyan geese, gene profiles in the pituitary gland of Huoyan geese taken during the laying period and ceased period were investigated using the suppression subtractive hybridization (SSH method. Total RNA was extracted from pituitary glands of ceased period and laying period geese. The cDNA in the pituitary glands of ceased geese was subtracted from the cDNA in the pituitary glands of laying geese (forward subtraction; the reverse subtraction was also performed. After sequencing and annotation, a total of 30 and 24 up and down-regulated genes were obtained from the forward and reverse SSH libraries, respectively. These genes mostly related to biosynthetic process, cellular nitrogen compound metabolic process, transport, cell differentiation, cellular protein modification process, signal transduction, small molecule metabolic process. Furthermore, eleven genes were selected for further analyses by quantitative real-time PCR (qRT-PCR. The qRT-PCR results for the most part were consistent with the SSH results. Among these genes, Synaptotagmin-1 (SYT1 and Stathmin-2 (STMN2 were substantially over-expressed in laying period compared to ceased period. These results could serve as an important reference for elucidating the molecular mechanism of higher laying performance in Huoyan geese.

27 CFR 70.244 - Payroll period.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Payroll period. 70.244... Excise and Special (Occupational) Tax Limitations § 70.244 Payroll period. For purpose of determining the... established calendar period regularly used by the employer or other person levied upon for payroll or payment...

40 CFR 35.9035 - Budget period.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Budget period. 35.9035 Section 35.9035... ASSISTANCE Financial Assistance for the National Estuary Program § 35.9035 Budget period. An applicant may choose its budget period in consultation with and subject to the approval of the Regional Administrator. ...

On positive periodic solution of periodic competition Lotka-Volterra system with time delay and diffusion

International Nuclear Information System (INIS)

Sun Wen; Chen Shihua; Hong Zhiming; Wang Changping

2007-01-01

A two-species periodic competition Lotka-Volterra system with time delay and diffusion is investigated. Some sufficient conditions of the existence of positive periodic solution are established for the system by using the continuation theorem of coincidence degree theory

Quasi-periodic luminosity variations in dwarf novae

International Nuclear Information System (INIS)

Robinson, E.L.; Nather, R.E.

1979-01-01

We have identified quasi-periodic oscillations in the light curves of five dwarf novae--U Gem, SS Cyg, RU Peg, KT Per, and VW Hyi-- and in the light curve of the quasi-periodic X-ray source Sco X-1. The mean periods of the quasi-periodic oscillations range from 32 s in SS Cyg to 147 s in KT Per and 165 s in Sco X-l. Their amplitudes are typically 0.005--0.0l mag. The properties of the quasi-periodic oscillations are represented well by a second-order autoregressive process. Use of this representation shows that the length of time over which the quasi-periodic oscillations maintain coherence is very short, typically 3--5 cycles of the oscillations. Thus the quasi-periodic oscillations can be distinguished from the short-period coherent oscillations in dwarf novae, which are usually interpreted as white dwarf pulsations, because t the periods of the quasi-periodic oscillations are 3--4 times longer and their coherence time is much shorter. The quasi-periodic oscillations occur in dwarf novae only during their eruptions and occur in Sco X-l only when the system is bright. The presence of the oscillations does not depend on the subclass to which a dwarf nova belongs or on the morphology of the individual eruptions. We argue that their short periods, their short coherence times, and their presence in Sco X-l require that the quasi-periodic oscillations be produced by the accretion disk, and not by the stars or by the boundary between the a accretion disk and its central star

49 CFR 236.588 - Periodic test.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Periodic test. 236.588 Section 236.588..., Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.588 Periodic test. Except as provided in § 236.586, periodic test of the automatic train stop, train control, or cab signal apparatus...

Periodicity in Age-Resolved Populations

Science.gov (United States)

Esipov, Sergei

We discuss the interplay between the non-linear diffusion and age-resolved population dynamics. Depending on the age properties of collective migration the system may exhibit continuous joint expansion of all ages or continuous expansion with age segregation. Between these two obvious limiting regimes there is an interesting window of periodic expansion, which has been previously used by us in modeling bacterial colonies of Proteus mirabilis. In order to test whether the age-dependent collective migration leads to periodicity in other systems we performed a Fourier analysis of historical data on ethnic expansions and found multiple co-existing periods of activity.

A case of Pseudo-Bartter syndrome

International Nuclear Information System (INIS)

Yang, Ik; Choi, Bo Whan; Lee, Yul; Chung, Soo Young

1994-01-01

Pseudo-Bartter Syndrome is a rare medical disease of the kidney characterized by normal blood pressure, hypokalemic metabolic alkalosis, hyperreninemia and hyperaldosteronism with drug history of diuretics. We report US, CT and MRI findings of a patients with clinically proved Pseudo-Bartter syndrome. The patient was a 37 year old woman with a history of long term ingestion of the diuretics(furosemide) for 20 years. Renal US revealed hyperechoic renal medulla at both kidneys. The resistive index(RI), calculated from the duplex doppler waveform is 0.61. Unenhanced CT revealed faint high attenuation along the medulla. T1-weighted MRI revealed indistinct corticomedullary differentiation

A case of Pseudo-Bartter syndrome

Energy Technology Data Exchange (ETDEWEB)

Yang, Ik; Choi, Bo Whan; Lee, Yul; Chung, Soo Young [College of Medicine, Hallym University, Seoul (Korea, Republic of)

1994-10-15

Pseudo-Bartter Syndrome is a rare medical disease of the kidney characterized by normal blood pressure, hypokalemic metabolic alkalosis, hyperreninemia and hyperaldosteronism with drug history of diuretics. We report US, CT and MRI findings of a patients with clinically proved Pseudo-Bartter syndrome. The patient was a 37 year old woman with a history of long term ingestion of the diuretics(furosemide) for 20 years. Renal US revealed hyperechoic renal medulla at both kidneys. The resistive index(RI), calculated from the duplex doppler waveform is 0.61. Unenhanced CT revealed faint high attenuation along the medulla. T1-weighted MRI revealed indistinct corticomedullary differentiation.

Anesthetic management of a patient with Bartter′s syndrome undergoing bilateral sagittal split osteotomy

Directory of Open Access Journals (Sweden)

Nasser Nooh

2012-01-01

Full Text Available Bartter′s syndrome is an unusual (estimated incidence is 1.2 per million people but important congenital form of secondary hyperaldosteronism; due to abnormalities in renal handling of electrolytes. It is associated with hypertrophy and hyperplasia of the juxtaglomerular cells, normal blood pressure, and hypokalemic alkalosis withoutedema.We present a 22-year-old woman with Bartter′s syndrome underwent bilateral sagittal split osteotomy to correct mandibular prognathic. The anesthetic management of Bartter′s syndrome should be relevant to the pathophysiology of the syndrome. Therefore, it should be directed toward maintaining cardiovascular stability, control of associated fluid, electrolyte and acid-base derangements, and the prevention of renal damage.

Distal renal tubular acidosis and amelogenesis imperfecta: A rare association

Directory of Open Access Journals (Sweden)

P Ravi

2013-01-01

Full Text Available Renal tubular acidosis (RTA is characterized by a normal anion gap with hyperchloremic metabolic acidosis. Primary distal RTA (type I is the most common RTA in children. Childhood presentation of distal RTA includes vomiting, failure to thrive, metabolic acidosis, and hypokalemia. Amelogenesis imperfecta (AI represents a condition where the dental enamel and oral tissues are affected in an equal manner resulting in the hypoplastic or hypopigmented teeth. We report a 10-year-old girl, previously asymptomatic presented with the hypokalemic paralysis and on work-up found out to have type I RTA. The discoloration of teeth and enamel was diagnosed as AI.

On the value of radioimmunologic myoglobin determination in skeletal muscle disorders

International Nuclear Information System (INIS)

Kiessling, W.R.; Beckmann, R.

1981-01-01

Using a sensitive radioimmunoassay (RIA) serum myoglobin (Mb) was measured in healthy controls, patients with skeletal muscle disorders (polymyositis, different types of progressive muscular dystrophy, hypokalemic myopathy and myopathy due to cortisone treatment) and as well in definite as possible carriers of Duchenne muscular dystrophy, DMD. The results indicate that Mb is a useful parameter in the assessment of muscle cell damage. Moreover, definite DMD-carriers had hypermyoglobine in 70% and in two of twenty possible DMD-carriers (all had normal CK activities) Mb was found to be markedly increased. The usefulness of an additional Mb determination in the detection of DMD-carriers is discussed. (orig.) [de

Value of radioimmunologic myoglobin determination in skeletal muscle disorders

Energy Technology Data Exchange (ETDEWEB)

Kiessling, W.R.; Beckmann, R.

1981-12-01

Using a sensitive radioimmunoassay (RIA) serum myoglobin (Mb) was measured in healthy controls, patients with skeletal muscle disorders (polymyositis, different types of progressive muscular dystrophy, hypokalemic myopathy and myopathy due to cortisone treatment) and as well in definite as possible carriers of Duchenne muscular dystrophy, DMD. The results indicate that Mb is a useful parameter in the assessment of muscle cell damage. Moreover, definite DMD-carriers had hypermyoglobine in 70% and in two of twenty possible DMD-carriers (all had normal CK activities) Mb was found to be markedly increased. The usefulness of an additional Mb determination in the detection of DMD-carriers is discussed.

Bi-periodicity evoked by periodic external inputs in delayed Cohen-Grossberg-type bidirectional associative memory networks

Science.gov (United States)

Cao, Jinde; Wang, Yanyan

2010-05-01

In this paper, the bi-periodicity issue is discussed for Cohen-Grossberg-type (CG-type) bidirectional associative memory (BAM) neural networks (NNs) with time-varying delays and standard activation functions. It is shown that the model considered in this paper has two periodic orbits located in saturation regions and they are locally exponentially stable. Meanwhile, some conditions are derived to ensure that, in any designated region, the model has a locally exponentially stable or globally exponentially attractive periodic orbit located in it. As a special case of bi-periodicity, some results are also presented for the system with constant external inputs. Finally, four examples are given to illustrate the effectiveness of the obtained results.

Bi-periodicity evoked by periodic external inputs in delayed Cohen-Grossberg-type bidirectional associative memory networks

International Nuclear Information System (INIS)

Cao Jinde; Wang Yanyan

2010-01-01

In this paper, the bi-periodicity issue is discussed for Cohen-Grossberg-type (CG-type) bidirectional associative memory (BAM) neural networks (NNs) with time-varying delays and standard activation functions. It is shown that the model considered in this paper has two periodic orbits located in saturation regions and they are locally exponentially stable. Meanwhile, some conditions are derived to ensure that, in any designated region, the model has a locally exponentially stable or globally exponentially attractive periodic orbit located in it. As a special case of bi-periodicity, some results are also presented for the system with constant external inputs. Finally, four examples are given to illustrate the effectiveness of the obtained results.

21 CFR 573.240 - Calcium periodate.

Science.gov (United States)

2010-04-01

... with calcium hydroxide or calcium oxide to form a substance consisting of not less than 60 percent by... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium periodate. 573.240 Section 573.240 Food... Additive Listing § 573.240 Calcium periodate. The food additive calcium periodate may be safely used in...

10 CFR 603.1295 - Periodic audit.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Periodic audit. 603.1295 Section 603.1295 Energy... Used in this Part § 603.1295 Periodic audit. An audit of a participant, performed at an agreed-upon... an audit may cover. A periodic audit of a participant differs from an award-specific audit of an...

Periodic table of elements

International Nuclear Information System (INIS)

Fluck, E.; Heumann, K.G.

1985-01-01

Following a recommendation by the International Union for Pure and Applied Chemistry (IUPAC), the groups of the periodic table shall be numbered from 1 to 18, instead of I to VIII as before. The recommendations has been approved of by the Committee on Nomenclature of the American Chemical Society. The new system abandons the distinction between main groups (a) and auxiliary groups (b), which in the past frequently has been the reason for misunderstandings between European and American chemists, due to different handling. The publishing house VCH Verlagsgesellschaft recently produced a new periodic table that shows the old and the new numbering system together at a glance, so that chemists will have time to get familiar with the new system. In addition the new periodic table represents an extensive data compilation arranged by elements. The front page lists the chemical properties of elements, the back page their physical properties. (orig./EF) [de

Scheduling periodic tasks with slack

NARCIS (Netherlands)

Korst, J.H.M.; Aarts, E.H.L.; Lenstra, J.K.

1997-01-01

We consider the problem of nonpreemptively scheduling periodic tasks on a minimum number of identical processors, assuming that some slack is allowed in the time between successive executions of a periodic task. We prove that the problem is NP-hard in the strong sense. Necessary and sufficient

Influence of Graves’ Disease on Psychocognitive State of Children and Adults (Literature Review

Directory of Open Access Journals (Sweden)

Sh.Т. Мuratova

2015-09-01

Full Text Available Psychoneurological changes in Graves’ disease are expressed in all patients at the early stages of the disease. Adolescents begin to do poorly in school, to skip school, there are changes in their behavior. Patients are characterized by the development of motor excitation, fidgeting, restlessness, hyperactivity, loss of memory, deterioration in school performance, sleep disturbances, movement disorders: tremor, rough, choreiform twitching of fingers and some muscle groups, thyrotoxic periodic paralysis may occur, which can last from a few minutes to several hours or even days. Anxiety syndromes associated with hyperthyroidism are usually complicated by depression and decreased cognitive functions such as memory and attention. In prospective studies, there were revealed a low level of non-verbal intelligence, verbal memory and cognitive function, increased anxiety, mood disorders, including depression, dementia, and Alzheimer’s disease; it is noted that after the rapid perception, there is its fast decrement, memory lapses, disorders in speech and self-awareness. Treating hyperthyroidism generally leads to an improvement in cognitive and behavioral disorders. However, cognitive function recover more slowly than the psychoemotional disorders, which ultimately leads to reduced quality of life, even after successful treatment of hyperthyroidism.

32 CFR 37.1325 - Periodic audit.

Science.gov (United States)

2010-07-01

... 32 National Defense 1 2010-07-01 2010-07-01 false Periodic audit. 37.1325 Section 37.1325 National... TECHNOLOGY INVESTMENT AGREEMENTS Definitions of Terms Used in This Part § 37.1325 Periodic audit. An audit of... awards. Appendix C to this part describes what such an audit may cover. A periodic audit of a participant...

Periodization Theory: Confronting an Inconvenient Truth.

Science.gov (United States)

Kiely, John

2018-04-01

Periodization theory has, over the past seven decades, emerged as the preeminent training planning paradigm. The philosophical underpinnings of periodization theory can be traced back to the integration of diverse shaping influences, whereby coaching beliefs and traditions were blended with historically available scientific insights and contextualized against pervading social planning models. Since then, many dimensions of elite preparation have evolved significantly, as driven by a combination of coaching innovations and science-led advances in training theory, techniques, and technologies. These advances have been incorporated into the fabric of the pre-existing periodization planning framework, yet the philosophical assumptions underpinning periodization remain largely unchallenged and unchanged. One particularly influential academic sphere of study, the science of stress, particularly the work of Hans Selye, is repeatedly cited by theorists as a central pillar upon which periodization theory is founded. A fundamental assumption emanating from the early stress research is that physical stress is primarily a biologically mediated phenomenon: a presumption translated to athletic performance contexts as evidence that mechanical training stress directly regulates the magnitude of subsequent 'fitness' adaptations. Interestingly, however, since periodization theory first emerged, the science of stress has evolved extensively from its historical roots. This raises a fundamental question: if the original scientific platform upon which periodization theory was founded has disintegrated, should we critically re-evaluate conventional perspectives through an updated conceptual lens? Realigning periodization philosophy with contemporary stress theory thus presents us with an opportunity to recalibrate training planning models with both contemporary scientific insight and progressive coaching practice.

A Three-period Samuelson-Diamond Growth Model

DEFF Research Database (Denmark)

Blomgren-Hansen, Niels

2005-01-01

Samuelson (1958) analyses a three-period model, whereas Diamod (1965) considers a two-period model. This difference poses the question whether the insights derived by analysing the simple two-period model carry over in the more complicated three-period case. They do. The Samuelson model (no produ...

Establishing contract periods

International Nuclear Information System (INIS)

Huffman, F.C.

1978-01-01

The lead time for executing the Adjustable Fixed-Commitment (AFC) contract and exceptions which may be considered are discussed. The initial delivery period is also discussed. Delays, deferrals, and schedule adjustment charges are finally considered

Period-dependent source rupture behavior of the 2011 Tohoku earthquake estimated by multi period-band Bayesian waveform inversion

Science.gov (United States)

Kubo, H.; Asano, K.; Iwata, T.; Aoi, S.

2014-12-01

Previous studies for the period-dependent source characteristics of the 2011 Tohoku earthquake (e.g., Koper et al., 2011; Lay et al., 2012) were based on the short and long period source models using different method. Kubo et al. (2013) obtained source models of the 2011 Tohoku earthquake using multi period-bands waveform data by a common inversion method and discussed its period-dependent source characteristics. In this study, to achieve more in detail spatiotemporal source rupture behavior of this event, we introduce a new fault surface model having finer sub-fault size and estimate the source models in multi period-bands using a Bayesian inversion method combined with a multi-time-window method. Three components of velocity waveforms at 25 stations of K-NET, KiK-net, and F-net of NIED are used in this analysis. The target period band is 10-100 s. We divide this period band into three period bands (10-25 s, 25-50 s, and 50-100 s) and estimate a kinematic source model in each period band using a Bayesian inversion method with MCMC sampling (e.g., Fukuda & Johnson, 2008; Minson et al., 2013, 2014). The parameterization of spatiotemporal slip distribution follows the multi-time-window method (Hartzell & Heaton, 1983). The Green's functions are calculated by the 3D FDM (GMS; Aoi & Fujiwara, 1999) using a 3D velocity structure model (JIVSM; Koketsu et al., 2012). The assumed fault surface model is based on the Pacific plate boundary of JIVSM and is divided into 384 subfaults of about 16 * 16 km^2. The estimated source models in multi period-bands show the following source image: (1) First deep rupture off Miyagi at 0-60 s toward down-dip mostly radiating relatively short period (10-25 s) seismic waves. (2) Shallow rupture off Miyagi at 45-90 s toward up-dip with long duration radiating long period (50-100 s) seismic wave. (3) Second deep rupture off Miyagi at 60-105 s toward down-dip radiating longer period seismic waves then that of the first deep rupture. (4) Deep

Periodical rocking long period gratings in PANDA fibers for high temperature and refractive index sensing

Science.gov (United States)

Jin, Wa; Bi, Wei-hong; Fu, Xing-hu; Fu, Guang-wei

2017-09-01

We report periodical rocking long period gratings (PR-LPGs) in PANDA fibers fabricated with CO2 laser. The PR-LPGs achieve very high coupling efficiency of 19 dB with 12 periods and a 3.5° twist angle in just one scanning cycle, which is much more effective than the conventional CO2 laser fabrication technique. This type of LPGs exhibits polarization-selective resonance dips which demonstrate different sensitivities to environmental parameters. The high temperature and external refractive index sensitivities are measured simultaneously, so it can be used as a wavelength-selective polarization filter and sensor.

Unstable periodic orbits and chaotic economic growth

International Nuclear Information System (INIS)

Ishiyama, K.; Saiki, Y.

2005-01-01

We numerically find many unstable periodic solutions embedded in a chaotic attractor in a macroeconomic growth cycle model of two countries with different fiscal policies, and we focus on a special type of the unstable periodic solutions. It is confirmed that chaotic behavior represented by the model is qualitatively and quantitatively related to the unstable periodic solutions. We point out that the structure of a chaotic solution is dissolved into a class of finite unstable periodic solutions picked out among a large number of periodic solutions. In this context it is essential for the unstable periodic solutions to be embedded in the chaotic attractor

The Periodic Table in Croatia

Directory of Open Access Journals (Sweden)

Raos, N.

2011-12-01

Full Text Available The Croatian (Yugoslav Academy of Sciences and Arts was the first academy to elect D. I. Mendeleev as its honorary member (1882, whereas the periodic table of the elements has been taught regularly at the Zagreb University since 1888. The early interest of Croatian chemists in the periodic table should be attributed primarily to their pan-Slavic attitude, particularly as proof that Slavic people were able to produce "their own Newtons" (M. V. Lomonosov and D. I. Mendeleev. Such enthusiastic views, however, did not help in analyzing the contribution of Mendeleev and other scientists to the discovery and development of the periodic table of the elements.

38 CFR 3.17 - Disability and death pension; Mexican border period and later war periods.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Disability and death pension; Mexican border period and later war periods. 3.17 Section 3.17 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension, Compensation, and Dependency and Indemnity...

Periodic subsystem density-functional theory

International Nuclear Information System (INIS)

Genova, Alessandro; Pavanello, Michele; Ceresoli, Davide

2014-01-01

By partitioning the electron density into subsystem contributions, the Frozen Density Embedding (FDE) formulation of subsystem Density Functional Theory (DFT) has recently emerged as a powerful tool for reducing the computational scaling of Kohn–Sham DFT. To date, however, FDE has been employed to molecular systems only. Periodic systems, such as metals, semiconductors, and other crystalline solids have been outside the applicability of FDE, mostly because of the lack of a periodic FDE implementation. To fill this gap, in this work we aim at extending FDE to treat subsystems of molecular and periodic character. This goal is achieved by a dual approach. On one side, the development of a theoretical framework for periodic subsystem DFT. On the other, the realization of the method into a parallel computer code. We find that periodic FDE is capable of reproducing total electron densities and (to a lesser extent) also interaction energies of molecular systems weakly interacting with metallic surfaces. In the pilot calculations considered, we find that FDE fails in those cases where there is appreciable density overlap between the subsystems. Conversely, we find FDE to be in semiquantitative agreement with Kohn–Sham DFT when the inter-subsystem density overlap is low. We also conclude that to make FDE a suitable method for describing molecular adsorption at surfaces, kinetic energy density functionals that go beyond the GGA level must be employed

Periodic subsystem density-functional theory

Science.gov (United States)

Genova, Alessandro; Ceresoli, Davide; Pavanello, Michele

2014-11-01

By partitioning the electron density into subsystem contributions, the Frozen Density Embedding (FDE) formulation of subsystem Density Functional Theory (DFT) has recently emerged as a powerful tool for reducing the computational scaling of Kohn-Sham DFT. To date, however, FDE has been employed to molecular systems only. Periodic systems, such as metals, semiconductors, and other crystalline solids have been outside the applicability of FDE, mostly because of the lack of a periodic FDE implementation. To fill this gap, in this work we aim at extending FDE to treat subsystems of molecular and periodic character. This goal is achieved by a dual approach. On one side, the development of a theoretical framework for periodic subsystem DFT. On the other, the realization of the method into a parallel computer code. We find that periodic FDE is capable of reproducing total electron densities and (to a lesser extent) also interaction energies of molecular systems weakly interacting with metallic surfaces. In the pilot calculations considered, we find that FDE fails in those cases where there is appreciable density overlap between the subsystems. Conversely, we find FDE to be in semiquantitative agreement with Kohn-Sham DFT when the inter-subsystem density overlap is low. We also conclude that to make FDE a suitable method for describing molecular adsorption at surfaces, kinetic energy density functionals that go beyond the GGA level must be employed.

Physical explanation of the periodic table.

Science.gov (United States)

Ostrovsky, V N

2003-05-01

The Periodic Table of the elements, the most important generalization in chemistry, is often considered as a representative special case in the study of the relation between chemistry and physics. Its quantum interpretation was initiated, but not completed, by Niels Bohr. In this paper, post-Bohr conceptual developments are discussed from historical and epistemological points of view. The difference between high-precision numerical calculations for individual atoms and the theory of the periodic system as a whole is emphasized. Periodic laws met in Nature are not restricted to the chemical Periodic Table. A comparative study of these laws makes it possible to single out essential features that define the particular pattern of periodicity. It is shown that the periodic system of neutral ground state atoms now has a firm nonempirical quantum-theoretical basis. Alternative approaches, based on group theory and other mathematical schemes, are briefly discussed. It is argued that, while quantum theory is capable of fully accurate calculations for relatively simple atoms or molecular objects, the complexity of polyatomic molecules and chemical reactions guarantees the flourishing of chemistry as a separate scientific discipline.

34 CFR 75.251 - The budget period.

Science.gov (United States)

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false The budget period. 75.251 Section 75.251 Education... Multi-Year Projects § 75.251 The budget period. (a) The Secretary usually approves a budget period of... budget period; and (2) Indicates his or her intention to make contination awards to fund the remainder of...

Wind Magnetic Clouds for the Period 2013 - 2015: Model Fitting, Types, Associated Shock Waves, and Comparisons to Other Periods

Science.gov (United States)

Lepping, R. P.; Wu, C.-C.; Berdichevsky, D. B.; Szabo, A.

2018-04-01

We give the results of parameter fitting of the magnetic clouds (MCs) observed by the Wind spacecraft for the three-year period 2013 to the end of 2015 (called the "Present" period) using the MC model of Lepping, Jones, and Burlaga ( J. Geophys. Res. 95, 11957, 1990). The Present period is almost coincident with the solar maximum of the sunspot number, which has a broad peak starting in about 2012 and extending to almost 2015. There were 49 MCs identified in the Present period. The modeling gives MC quantities such as size, axial attitude, field handedness, axial magnetic-field strength, center time, and closest-approach vector. Derived quantities are also estimated, such as axial magnetic flux, axial current density, and total axial current. Quality estimates are assigned representing excellent, fair/good, and poor. We provide error estimates on the specific fit parameters for the individual MCs, where the poor cases are excluded. Model-fitting results that are based on the Present period are compared to the results of the full Wind mission from 1995 to the end of 2015 (Long-term period), and compared to the results of two other recent studies that encompassed the periods 2007 - 2009 and 2010 - 2012, inclusive. We see that during the Present period, the MCs are, on average, slightly slower, slightly weaker in axial magnetic field (by 8.7%), and larger in diameter (by 6.5%) than those in the Long-term period. However, in most respects, the MCs in the Present period are significantly closer in characteristics to those of the Long-term period than to those of the two recent three-year periods. However, the rate of occurrence of MCs for the Long-term period is 10.3 year^{-1}, whereas this rate for the Present period is 16.3 year^{-1}, similar to that of the period 2010 - 2012. Hence, the MC occurrence rate has increased appreciably in the last six years. MC Type (N-S, S-N, All N, All S, etc.) is assigned to each MC; there is an inordinately large percentage of All S

Discovering Periodicity: Hands-On, Minds-On Organization of the Periodic Table by Visualizing the Unseen

Science.gov (United States)

Selco, Jodye; Bruno, Mary; Chan, Sue

2013-01-01

Understanding how the periodic table of elements is organized and how to read information from it is fundamental for understanding chemistry. Introductory chemistry courses usually include discussions detailing what elemental information can be determined by virtue of its position on the periodic table. Although many people have been exposed to…

Periodical test program in depth revision

International Nuclear Information System (INIS)

Feltin, C.; Zermizoglou, R.

1987-11-01

Inspection visits made to different sites during 1980 and 1981 evidenced the need to extend and define more precisely the periodical tests performed on safety related systems; thus Electricite de France was requested by the Safety Authorities to re-examine the periodical test program for all safety related systems. This paper presents the methodology adopted by Electricite de France in order to perform an exhaustive analysis of the periodical test program for the 900 and 1300 MWe plants, and the organization set up at the IPSN at one hand and Electricite de France on the other hand for the purpose of elaborating a periodical test program which would be ratified by the Safety Authorities

From the Mendeleev periodic table to particle physics and back to the periodic table

International Nuclear Information System (INIS)

Kibler, Maurice R.

2006-11-01

We briefly describe in this paper the passage from Mendeleev's chemistry (1869) to atomic physics (in the 1900's), nuclear physics (in the 1932's) and particle physics (from 1953 to 2006). We show how the consideration of symmetries, largely used in physics since the end of the 1920's, gave rise to a new format of the periodic table in the 1970's. More specifically, this paper is concerned with the application of the group SO(4,2)xSU(2) to the periodic table of chemical elements. It is shown how the Madelung rule of the atomic shell model can be used for setting up a periodic table that can be further rationalized via the group SO(4,2)xSU(2) and some of its subgroups. Qualitative results are obtained from this nonstandard table. (author)

Co-periodic stability of periodic waves in some Hamiltonian PDEs

Science.gov (United States)

Benzoni-Gavage, S.; Mietka, C.; Rodrigues, L. M.

2016-10-01

The stability of periodic traveling wave solutions to dispersive PDEs with respect to ‘arbitrary’ perturbations is still widely open. The focus is put here on stability with respect to perturbations of the same period as the wave, for KdV-like systems of one-dimensional Hamiltonian PDEs. Stability criteria are derived and investigated first in a general abstract framework, and then applied to three basic examples that are very closely related, and ubiquitous in mathematical physics, namely, a quasilinear version of the generalized Korteweg-de Vries equation (qKdV), and the Euler-Korteweg system in both Eulerian coordinates (EKE) and in mass Lagrangian coordinates (EKL). Those criteria consist of a necessary condition for spectral stability, and of a sufficient condition for orbital stability. Both are expressed in terms of a single function, the abbreviated action integral along the orbits of waves in the phase plane, which is the counterpart of the solitary waves moment of instability introduced by Boussinesq. Regarding solitary waves, the celebrated Grillakis-Shatah-Strauss stability criteria amount to looking for the sign of the second derivative of the moment of instability with respect to the wave speed. For periodic waves, the most striking results obtained here can be summarized as: an odd value for the difference between N—the size of the PDE system—and the negative signature of the Hessian of the action implies spectral instability, whereas a negative signature of the same Hessian being equal to N implies orbital stability. Since these stability criteria are merely encoded by the negative signature of matrices, they can at least be checked numerically. Various numerical experiments are presented, which clearly discriminate between stable cases and unstable cases for (qKdV), (EKE) and (EKL).

Periodic orbits near the particle resonance in galaxies

CERN Document Server

Contopoulos, George

1978-01-01

Near the particle resonance of a spiral galaxy the almost circular periodic orbits that exist inside the resonance (direct) or outside it (retrograde) are replaced by elongated trapped orbits around the maxima of the potential L/sub 4/ and L/sub 5/. These are the long- period trapped periodic orbits. The long-period orbits shrink to the points L/sub 4/, L/sub 5/ for a critical value of the Hamiltonian h. For still larger h, a family of short-period trapped orbits appears, with continuously growing size. The evolution of the periodic orbits with h is followed, theoretically and numerically, from the untrapped orbits to the long-periodic orbits and then to the short-periodic orbits, mainly in the case of a bar. In a tight spiral case an explanation of the asymmetric periodic and banana orbits is given, and an example of short-period orbits not surrounding L/sub 4/ or L/sub 5/ is provided. Another family of periodic orbits reaching corotation is trapped at the inner Lindblad resonance. (5 refs).

May flood-poor periods be more dangerous than flood-rich periods?

Science.gov (United States)

Salinas, Jose Luis; Di Baldassarre, Giuliano; Viglione, Alberto; Kuil, Linda; Bloeschl, Guenter

2014-05-01

River floods are among the most devastating natural hazards experienced by populations that, since the earliest recorded civilisations, have settled in floodplains because they offer favourable conditions for trade, agriculture, and economic development. The occurrence of a flood may cause loss of lives and tremendous economic damages and, therefore, is rightly seen as a very negative event by the communities involved. Occurrence of many floods in a row is, of course, even more frustrating and is rightly considered a unbearable calamity. Unfortunately, the occurrence of many floods in a limited number of consecutive years is not unusual. In many places in the world, it has been observed that extreme floods do not arrive randomly but cluster in time into flood-poor and flood-rich periods consistent with the Hurst effect. If this is the case, when are the people more in danger? When should people be more scared? In flood-poor or flood-rich periods? In this work, a Socio-Hydrology model (Di Baldassarre et al., 2013; Viglione et al., 2014) is used to show that, maybe counter-intuitively, flood-poor periods may be more dangerous than flood-rich periods. The model is a conceptualisation of a hypothetical setting of a city at a river where a community evolves, making choices between flood management options on the floodplain. The most important feedbacks between the economic, political, technological and hydrological processes of the evolution of that community are represented in the model. In particular, the model also accounts in a dynamic way for the evolution of the the community awareness to flood risk. Occurrence of floods tends to increase peoples' recognition that their property is in an area that is potentially at risk of flooding, both at the scales of individuals and communities, which is one of the main reasons why flood coping actions are taken. It is shown through examples that frequent flood events may result in moderate damages because they ensure that the

Hypokalemic paralysis and respiratory failure due to excessive intake of licorice syrup

Directory of Open Access Journals (Sweden)

Mehmet Oguzhan Ay

2014-04-01

Full Text Available Licorice is the root of Glycyrrhiza glabra, which has a herbal ingredient, glycyrrhizic acid. Excessive intake of licorice may cause a hypermineralocorticoidism-like syndrome characterized by sodium and water retention, hypokalemia, hypertension, metabolic alkalosis, low-renin activity, and hypoaldosteronism. In this paper, an 34 years old man who admitted to the emergency department with respiratory failure and marked muscle weakness of all extremities that progressed to paralysis after excessive intake of licorice syrup was presented. It was aimed to draw attention to the necessity of questioning whether there is excessive intake of licorice or not in patients who admitted to emergency department with paralysis and dyspnea. Plasma potassium concentration of the patient was 1.4 mmol/L. The patient\\'s respiratory distress and loss of muscle strength recovered completely after potassium replacement. [Cukurova Med J 2014; 39(2.000: 387-391

Distal renal tubular acidosis and hypokalemic paralysis in a patient with hypothyroidism

Directory of Open Access Journals (Sweden)

Parvaiz Ahmad Koul

2011-01-01

Full Text Available A 43- year- old woman on treatment for primary hypothyroidism presented with 1- day progressive weakness of all her limbs and history of similar episodes in the past. Clinical examination revealed grade 2 hyporeflexive weakness. Investigations revealed features of hypokalemia, metabolic acidosis, alkaline urine, and a fractional bicarbonate excretion of 3.5%, consistent with distal renal tubular acidosis. Antithyroid peroxidase and antithroglobulin antibodies were positive, suggesting an autoimmune basis for the pathogenesis of the functional tubular defect. Bicarbonate therapy resulted in a sustained clinical recovery.

A technique to detect periodic and non-periodic ultra-rapid flux time variations with standard radio-astronomical data

Science.gov (United States)

Borra, Ermanno F.; Romney, Jonathan D.; Trottier, Eric

2018-06-01

We demonstrate that extremely rapid and weak periodic and non-periodic signals can easily be detected by using the autocorrelation of intensity as a function of time. We use standard radio-astronomical observations that have artificial periodic and non-periodic signals generated by the electronics of terrestrial origin. The autocorrelation detects weak signals that have small amplitudes because it averages over long integration times. Another advantage is that it allows a direct visualization of the shape of the signals, while it is difficult to see the shape with a Fourier transform. Although Fourier transforms can also detect periodic signals, a novelty of this work is that we demonstrate another major advantage of the autocorrelation, that it can detect non-periodic signals while the Fourier transform cannot. Another major novelty of our work is that we use electric fields taken in a standard format with standard instrumentation at a radio observatory and therefore no specialized instrumentation is needed. Because the electric fields are sampled every 15.625 ns, they therefore allow detection of very rapid time variations. Notwithstanding the long integration times, the autocorrelation detects very rapid intensity variations as a function of time. The autocorrelation could also detect messages from Extraterrestrial Intelligence as non-periodic signals.

From the Mendeleev periodic table to particle physics and back to the periodic table

Energy Technology Data Exchange (ETDEWEB)

Kibler, Maurice R. [Universite de Lyon, Institut de Physique Nucleaire, Universite Lyon 1 and CNRS/IN2P3, 43 Bd du 11 Novembre 1918, F-69622 Villeurbanne Cedex (France)

2006-11-15

We briefly describe in this paper the passage from Mendeleev's chemistry (1869) to atomic physics (in the 1900's), nuclear physics (in the 1932's) and particle physics (from 1953 to 2006). We show how the consideration of symmetries, largely used in physics since the end of the 1920's, gave rise to a new format of the periodic table in the 1970's. More specifically, this paper is concerned with the application of the group SO(4,2)xSU(2) to the periodic table of chemical elements. It is shown how the Madelung rule of the atomic shell model can be used for setting up a periodic table that can be further rationalized via the group SO(4,2)xSU(2) and some of its subgroups. Qualitative results are obtained from this nonstandard table. (author)

Autoinflammatory Diseases with Periodic Fevers.

Science.gov (United States)

Sag, Erdal; Bilginer, Yelda; Ozen, Seza

2017-07-01

One purpose of this review was to raise awareness for the new autoinflammatory syndromes. These diseases are increasingly recognized and are in the differential diagnosis of many disease states. We also aimed to review the latest recommendations for the diagnosis, management, and treatment of these patients. Familial Mediterranean fever (FMF), cryopyrin-associated periodic syndrome (CAPS), tumor necrosis factor receptor-associated periodic fever syndrome (TRAPS), and hyperimmunoglobulinemia D and periodic fever syndrome/mevalonate kinase deficiency (HIDS/MVKD) are the more common autoinflammatory diseases that are characterized by periodic fevers and attacks of inflammation. Recently much collaborative work has been done to understand the characteristics of these patients and to develop recommendations to guide the physicians in the care of these patients. These recent recommendations will be summarized for all four diseases. FMF is the most common periodic fever disease. We need to further understand the pathogenesis and the role of single mutations in the disease. Recently, the management and treatment of the disease have been nicely reviewed. CAPS is another interesting disease associated with severe complications. Anti-interleukin-1 (anti-IL-1) treatment provides cure for these patients. TRAPS is characterized by the longest delay in diagnosis; thus, both pediatricians and internists should be aware of the characteristic features and the follow-up of these patients. HIDS/MVKD is another autoinflammatory diseases characterized with fever attacks. The spectrum of disease manifestation is rather large in this disease, and we need further research on biomarkers for the optimal management of these patients.

PERIODIC SIGNALS IN BINARY MICROLENSING EVENTS

International Nuclear Information System (INIS)

Guo, Xinyi; Stefano, Rosanne Di; Esin, Ann; Taylor, Jeffrey

2015-01-01

Gravitational microlensing events are powerful tools for the study of stellar populations. In particular, they can be used to discover and study a variety of binary systems. A large number of binary lenses have already been found through microlensing surveys and a few of these systems show strong evidence of orbital motion on the timescale of the lensing event. We expect that more binary lenses of this kind will be detected in the future. For binaries whose orbital period is comparable to the event duration, the orbital motion can cause the lensing signal to deviate drastically from that of a static binary lens. The most striking property of such light curves is the presence of quasi-periodic features, which are produced as the source traverses the same regions in the rotating lens plane. These repeating features contain information about the orbital period of the lens. If this period can be extracted, then much can be learned about the lensing system even without performing time-consuming, detailed light-curve modeling. However, the relative transverse motion between the source and the lens significantly complicates the problem of period extraction. To resolve this difficulty, we present a modification of the standard Lomb–Scargle periodogram analysis. We test our method for four representative binary lens systems and demonstrate its efficiency in correctly extracting binary orbital periods

Periodicity and repeatability in data

Science.gov (United States)

Southwood, D.

Using magnetic data from the first two years in Saturn orbit, the basic periodicity of apparent is examined with the aim of elucidating the `cam' shaft model of Espinosa et al. (2003) identifying the nature of the `cam' and giving a definitive period for its rotation. An initial hypothesis, supported by the spectral analysis of analysis of the first 8 months in orbit Gianpieri et al. (2006), is made that the source of the period is linked to something inside the planet and therefore that the source inertia means that the period effectively does not change over the 2 years. Moreover one expects that the source phase is fixed. Using this approach, not only can the period identified by spectral analysis (647.1 + 0.6 min.) be verified but also by phase analysis between successive passes over the 2 years the period can be refined to 647.6 + 0.1 min. The signal itself is remarkably reproducible from pass to pass. It appears in all three components of the field and its polarisation is unambiguously not attributable to direct detection of an internal field. Not only does the signal not decay rapidly with distance from the planet, but although it has the m=1 symmetry of a tilted dipole, the field lines diverge from the planet indicating an exterior source. This feature led to the `cam' model. The polarisation and comparisons of passes with different latitude profiles show a surprising north-south symmetry in the azimuthal field. The absence of asymmetry with respect to the magnetic equator rules out a direct magnetospheric-ionospheric interaction source. Accordingly, it is proposed that the basic `cam' effect is generated by a single hemisphere anomaly which creates hemisphere to hemisphere field aligned currents. The existence of Saturn phase related anomaly appears to produce a basic asymmetry in the inner magnetosphere that sets the phase of both an inflowing and outflowing sector in a rotating circulation system.

The transition mechanism from a symmetric single period discharge to a period-doubling discharge in atmospheric helium dielectric-barrier discharge

International Nuclear Information System (INIS)

Zhang, Dingzong; Wang, Yanhui; Wang, Dezhen

2013-01-01

Period-doubling and chaos phenomenon have been frequently observed in atmospheric-pressure dielectric-barrier discharges. However, how a normal single period discharge bifurcates into period-doubling state is still unclear. In this paper, by changing the driving frequency, we study numerically the transition mechanisms from a normal single period discharge to a period-doubling state using a one-dimensional self-consistent fluid model. The results show that before a discharge bifurcates into a period-doubling state, it first deviates from its normal operation and transforms into an asymmetric single period discharge mode. Then the weaker discharge in this asymmetric discharge will be enhanced gradually with increasing of the frequency until it makes the subsequent discharge weaken and results in the discharge entering a period-doubling state. In the whole transition process, the spatial distribution of the charged particle density and the electric field plays a definitive role. The conclusions are further confirmed by changing the gap width and the amplitude of the applied voltage

The transition mechanism from a symmetric single period discharge to a period-doubling discharge in atmospheric helium dielectric-barrier discharge

Energy Technology Data Exchange (ETDEWEB)

Zhang, Dingzong; Wang, Yanhui; Wang, Dezhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

2013-06-15

Period-doubling and chaos phenomenon have been frequently observed in atmospheric-pressure dielectric-barrier discharges. However, how a normal single period discharge bifurcates into period-doubling state is still unclear. In this paper, by changing the driving frequency, we study numerically the transition mechanisms from a normal single period discharge to a period-doubling state using a one-dimensional self-consistent fluid model. The results show that before a discharge bifurcates into a period-doubling state, it first deviates from its normal operation and transforms into an asymmetric single period discharge mode. Then the weaker discharge in this asymmetric discharge will be enhanced gradually with increasing of the frequency until it makes the subsequent discharge weaken and results in the discharge entering a period-doubling state. In the whole transition process, the spatial distribution of the charged particle density and the electric field plays a definitive role. The conclusions are further confirmed by changing the gap width and the amplitude of the applied voltage.

Validity and Reliability of the Korean Version of the Hyperthyroidism Symptom Scale.

Science.gov (United States)

Lee, Jie Eun; Lee, Dong Hwa; Oh, Tae Jung; Kim, Kyoung Min; Choi, Sung Hee; Lim, Soo; Park, Young Joo; Park, Do Joon; Jang, Hak Chul; Moon, Jae Hoon

2018-03-01

Thyrotoxicosis is a common disease resulting from an excess of thyroid hormones, which affects many organ systems. The clinical symptoms and signs are relatively nonspecific and can vary depending on age, sex, comorbidities, and the duration and cause of the disease. Several symptom rating scales have been developed in an attempt to assess these symptoms objectively and have been applied to diagnosis or to evaluation of the response to treatment. The aim of this study was to assess the reliability and validity of the Korean version of the hyperthyroidism symptom scale (K-HSS). Twenty-eight thyrotoxic patients and 10 healthy subjects completed the K-HSS at baseline and after follow-up at Seoul National University Bundang Hospital. The correlation between K-HSS scores and thyroid function was analyzed. K-HSS scores were compared between baseline and follow-up in patient and control groups. Cronbach's α coefficient was calculated to demonstrate the internal consistency of K-HSS. The mean age of the participants was 34.7±9.8 years and 13 (34.2%) were men. K-HSS scores demonstrated a significant positive correlation with serum free thyroxine concentration and decreased significantly with improved thyroid function. K-HSS scores were highest in subclinically thyrotoxic subjects, lower in patients who were euthyroid after treatment, and lowest in the control group at follow-up, but these differences were not significant. Cronbach's α coefficient for the K-HSS was 0.86. The K-HSS is a reliable and valid instrument for evaluating symptoms of thyrotoxicosis in Korean patients. Copyright © 2018 Korean Endocrine Society.

Validity and Reliability of the Korean Version of the Hyperthyroidism Symptom Scale

Directory of Open Access Journals (Sweden)

Jie-Eun Lee

2018-03-01

Full Text Available BackgroundThyrotoxicosis is a common disease resulting from an excess of thyroid hormones, which affects many organ systems. The clinical symptoms and signs are relatively nonspecific and can vary depending on age, sex, comorbidities, and the duration and cause of the disease. Several symptom rating scales have been developed in an attempt to assess these symptoms objectively and have been applied to diagnosis or to evaluation of the response to treatment. The aim of this study was to assess the reliability and validity of the Korean version of the hyperthyroidism symptom scale (K-HSS.MethodsTwenty-eight thyrotoxic patients and 10 healthy subjects completed the K-HSS at baseline and after follow-up at Seoul National University Bundang Hospital. The correlation between K-HSS scores and thyroid function was analyzed. K-HSS scores were compared between baseline and follow-up in patient and control groups. Cronbach's α coefficient was calculated to demonstrate the internal consistency of K-HSS.ResultsThe mean age of the participants was 34.7±9.8 years and 13 (34.2% were men. K-HSS scores demonstrated a significant positive correlation with serum free thyroxine concentration and decreased significantly with improved thyroid function. K-HSS scores were highest in subclinically thyrotoxic subjects, lower in patients who were euthyroid after treatment, and lowest in the control group at follow-up, but these differences were not significant. Cronbach's α coefficient for the K-HSS was 0.86.ConclusionThe K-HSS is a reliable and valid instrument for evaluating symptoms of thyrotoxicosis in Korean patients.

Validity and Reliability of the Korean Version of the Hyperthyroidism Symptom Scale

Science.gov (United States)

Lee, Dong Hwa

2018-01-01

Background Thyrotoxicosis is a common disease resulting from an excess of thyroid hormones, which affects many organ systems. The clinical symptoms and signs are relatively nonspecific and can vary depending on age, sex, comorbidities, and the duration and cause of the disease. Several symptom rating scales have been developed in an attempt to assess these symptoms objectively and have been applied to diagnosis or to evaluation of the response to treatment. The aim of this study was to assess the reliability and validity of the Korean version of the hyperthyroidism symptom scale (K-HSS). Methods Twenty-eight thyrotoxic patients and 10 healthy subjects completed the K-HSS at baseline and after follow-up at Seoul National University Bundang Hospital. The correlation between K-HSS scores and thyroid function was analyzed. K-HSS scores were compared between baseline and follow-up in patient and control groups. Cronbach's α coefficient was calculated to demonstrate the internal consistency of K-HSS. Results The mean age of the participants was 34.7±9.8 years and 13 (34.2%) were men. K-HSS scores demonstrated a significant positive correlation with serum free thyroxine concentration and decreased significantly with improved thyroid function. K-HSS scores were highest in subclinically thyrotoxic subjects, lower in patients who were euthyroid after treatment, and lowest in the control group at follow-up, but these differences were not significant. Cronbach's α coefficient for the K-HSS was 0.86. Conclusion The K-HSS is a reliable and valid instrument for evaluating symptoms of thyrotoxicosis in Korean patients. PMID:29589389

Time-Varying Periodicity in Intraday Volatility

DEFF Research Database (Denmark)

Andersen, Torben Gustav; Thyrsgaard, Martin; Todorov, Viktor

We develop a nonparametric test for deciding whether return volatility exhibits time-varying intraday periodicity using a long time-series of high-frequency data. Our null hypothesis, commonly adopted in work on volatility modeling, is that volatility follows a stationary process combined...... with a constant time-of-day periodic component. We first construct time-of-day volatility estimates and studentize the high-frequency returns with these periodic components. If the intraday volatility periodicity is invariant over time, then the distribution of the studentized returns should be identical across...... with estimating volatility moments through their sample counterparts. Critical values are computed via easy-to-implement simulation. In an empirical application to S&P 500 index returns, we find strong evidence for variation in the intraday volatility pattern driven in part by the current level of volatility...

Economic comparison of a sixty day dry period with no dry period on Dutch dairy farms

NARCIS (Netherlands)

Heeren, J.A.H.; Steeneveld, W.; Berentsen, P.B.M.

2014-01-01

In the Netherlands it is general practice that dairy cows have a dry period of six to eight weeks. Research, however, shows that omission of the dry period avoids the negative energy balance after calving with its potential negative effects on metabolic disorders, infectious diseases, and fertility.

Three dimensional periodic foundations for base seismic isolation

International Nuclear Information System (INIS)

Yan, Y; Mo, Y L; Cheng, Z; Shi, Z; Menq, F; Tang, Y

2015-01-01

Based on the concept of phononic crystals, periodic foundations made of periodic materials are investigated in this paper. The periodic foundations can provide low frequency band gaps, which cover the main frequency ranges of seismic waves. Therefore, the periodic foundations are able to protect the upper structures during earthquake events. In this paper, the basic theory of three dimensional periodic foundations is studied and the finite element method was used to conduct the sensitivity study. A simplified three-dimensional periodic foundation with a superstructure was tested in the field and the feasibility of three dimensional periodic foundations was proved. The test results showed that the response of the upper structure with the three dimensional periodic foundation was reduced under excitation waves with the main frequency falling in the attenuation zones. The finite element analysis results are consistent with the experimental data, indicating that three dimensional periodic foundations are a feasible way of reducing seismic vibrations. (paper)

Periodic solutions of dissipative systems revisited

Directory of Open Access Journals (Sweden)

Górniewicz Lech

2006-01-01

Full Text Available We reprove in an extremely simple way the classical theorem that time periodic dissipative systems imply the existence of harmonic periodic solutions, in the case of uniqueness. We will also show that, in the lack of uniqueness, the existence of harmonics is implied by uniform dissipativity. The localization of starting points and multiplicity of periodic solutions will be established, under suitable additional assumptions, as well. The arguments are based on the application of various asymptotic fixed point theorems of the Lefschetz and Nielsen type.

Periodic solutions of dissipative systems revisited

Directory of Open Access Journals (Sweden)

Lech Górniewicz

2006-05-01

Full Text Available We reprove in an extremely simple way the classical theorem that time periodic dissipative systems imply the existence of harmonic periodic solutions, in the case of uniqueness. We will also show that, in the lack of uniqueness, the existence of harmonics is implied by uniform dissipativity. The localization of starting points and multiplicity of periodic solutions will be established, under suitable additional assumptions, as well. The arguments are based on the application of various asymptotic fixed point theorems of the Lefschetz and Nielsen type.

Kir2.1 channels set two levels of resting membrane potential with inward rectification.

Science.gov (United States)

Chen, Kuihao; Zuo, Dongchuan; Liu, Zheng; Chen, Haijun

2018-04-01

Strong inward rectifier K + channels (Kir2.1) mediate background K + currents primarily responsible for maintenance of resting membrane potential. Multiple types of cells exhibit two levels of resting membrane potential. Kir2.1 and K2P1 currents counterbalance, partially accounting for the phenomenon of human cardiomyocytes in subphysiological extracellular K + concentrations or pathological hypokalemic conditions. The mechanism of how Kir2.1 channels contribute to the two levels of resting membrane potential in different types of cells is not well understood. Here we test the hypothesis that Kir2.1 channels set two levels of resting membrane potential with inward rectification. Under hypokalemic conditions, Kir2.1 currents counterbalance HCN2 or HCN4 cation currents in CHO cells that heterologously express both channels, generating N-shaped current-voltage relationships that cross the voltage axis three times and reconstituting two levels of resting membrane potential. Blockade of HCN channels eliminated the phenomenon in K2P1-deficient Kir2.1-expressing human cardiomyocytes derived from induced pluripotent stem cells or CHO cells expressing both Kir2.1 and HCN2 channels. Weakly inward rectifier Kir4.1 or inward rectification-deficient Kir2.1•E224G mutant channels do not set such two levels of resting membrane potential when co-expressed with HCN2 channels in CHO cells or when overexpressed in human cardiomyocytes derived from induced pluripotent stem cells. These findings demonstrate a common mechanism that Kir2.1 channels set two levels of resting membrane potential with inward rectification by balancing inward currents through different cation channels such as hyperpolarization-activated HCN channels or hypokalemia-induced K2P1 leak channels.

Multi-periodic nanostructures for photon control

DEFF Research Database (Denmark)

Kluge, Christian; Adam, Jost; Barié, Nicole

2014-01-01

We propose multi-periodic nanostructures yielded by superposition of multiple binary gratings for wide control over photon emission in thin-film devices. We present wavelength- and angle-resolved photoluminescence measurements of multi-periodically nanostructured organic light-emitting layers...

Multiphase averaging of periodic soliton equations

International Nuclear Information System (INIS)

Forest, M.G.

1979-01-01

The multiphase averaging of periodic soliton equations is considered. Particular attention is given to the periodic sine-Gordon and Korteweg-deVries (KdV) equations. The periodic sine-Gordon equation and its associated inverse spectral theory are analyzed, including a discussion of the spectral representations of exact, N-phase sine-Gordon solutions. The emphasis is on physical characteristics of the periodic waves, with a motivation from the well-known whole-line solitons. A canonical Hamiltonian approach for the modulational theory of N-phase waves is prescribed. A concrete illustration of this averaging method is provided with the periodic sine-Gordon equation; explicit averaging results are given only for the N = 1 case, laying a foundation for a more thorough treatment of the general N-phase problem. For the KdV equation, very general results are given for multiphase averaging of the N-phase waves. The single-phase results of Whitham are extended to general N phases, and more importantly, an invariant representation in terms of Abelian differentials on a Riemann surface is provided. Several consequences of this invariant representation are deduced, including strong evidence for the Hamiltonian structure of N-phase modulational equations

Periods found in heat measurements obtained by calorimetry

International Nuclear Information System (INIS)

Jordan, K.C.

1984-01-01

During a span of 640 days, a periodicity of 1.5158 +- 0.0008 days was discovered in successive heater equilibria on Calorimeter No. 127. Measurements were taken at 12-h intervals, with occasional changes of exactly 3 or 6 h in the schedule of measurements. This schedule eliminated all other possible periods except a period of 0.150156 days. Periods of 1.519125 and 1.511283 days were discovered in data on the excess length of day as obtained by the US Naval Observatory over a period of 24 y. These two periods could equally well represent periods of 0.150189 and 0.150112 days, since measurements were obtained only once every 24 h. It is suggested that periods observed in sensitive calorimeters and in length of day data may be related. 1 reference, 6 figures, 5 tables

Approaches and Methods of Periodization in Literary History

Directory of Open Access Journals (Sweden)

Naser Gholi Sarli

2013-10-01

Full Text Available Abstract One of the most fundamental acts of historiography is to classify historical information in diachronic axis. The method of this classification or periodization shows the theoretical approach of the historian and determines the structure and the form of his history. Because of multiple criteria of analysis and various literary genres, periodization in literary history is more complicated than that of general history. We can distinguish two approaches in periodization of literary history, although these can be used together: extrinsic or social-cultural approach (based on criteria extrinsic to literature and intrinsic or formalist approach (based on criteria intrinsic to literature. Then periodization in literary history can be formulated in different methods and may be based upon various criteria: chronological such as century, decade and year organic patterns of evolution great poets and writers literary emblems and evaluations of every period events, concepts and periods of general or political history analogy of literary history and history of ideas or history of arts approaches and styles of language dominant literary norms. These methods actually are used together and everyone has adequacy in special kind of literary history. In periodization of Persian contemporary literature, some methods and models current in periodization of poetry have been applied identically to periodization of prose. Periodization based upon century, decade and year is the simplest and most mechanical method but sometimes certain centuries in some countries have symbolic and stylistic meaning, and decades were used often for subdivisions of literary history, especially nowadays with fast rhythm of literary change. Periodization according to organic patterns of evolution equates the changes of literary history with the life phases of an organism, and offers an account of birth, mature and death (and sometimes re-birth of literary genres, but this method have

Approaches and Methods of Periodization in Literary History

Directory of Open Access Journals (Sweden)

Dr. N. Gh. Sarli

Full Text Available One of the most fundamental acts of historiography is to classify historical information in diachronic axis. The method of this classification or periodization shows the theoretical approach of the historian and determines the structure and the form of his history. Because of multiple criteria of analysis and various literary genres, periodization in literary history is more complicated than that of general history. We can distinguish two approaches in periodization of literary history, although these can be used together: extrinsic or social-cultural approach (based on criteria extrinsic to literature and intrinsic or formalist approach (based on criteria intrinsic to literature. Then periodization in literary history can be formulated in different methods and may be based upon various criteria: chronological such as century, decade and year; organic patterns of evolution; great poets and writers; literary emblems and evaluations of every period; events, concepts and periods of general or political history; analogy of literary history and history of ideas or history of arts; approaches and styles of language; dominant literary norms. These methods actually are used together and everyone has adequacy in special kind of literary history. In periodization of Persian contemporary literature, some methods and models current in periodization of poetry have been applied identically to periodization of prose. Periodization based upon century, decade and year is the simplest and most mechanical method but sometimes certain centuries in some countries have symbolic and stylistic meaning, and decades were used often for subdivisions of literary history, especially nowadays with fast rhythm of literary change.Periodization according to organic patterns of evolution equates the changes of literary history with the life phases of an organism, and offers an account of birth, mature and death (and sometimes re-birth of literary genres, but this method have

Approaches and Methods of Periodization in Literary History

Directory of Open Access Journals (Sweden)

Naser Gholi Sarli

2013-11-01

Full Text Available Abstract One of the most fundamental acts of historiography is to classify historical information in diachronic axis. The method of this classification or periodization shows the theoretical approach of the historian and determines the structure and the form of his history. Because of multiple criteria of analysis and various literary genres, periodization in literary history is more complicated than that of general history. We can distinguish two approaches in periodization of literary history, although these can be used together: extrinsic or social-cultural approach (based on criteria extrinsic to literature and intrinsic or formalist approach (based on criteria intrinsic to literature. Then periodization in literary history can be formulated in different methods and may be based upon various criteria: chronological such as century, decade and year organic patterns of evolution great poets and writers literary emblems and evaluations of every period events, concepts and periods of general or political history analogy of literary history and history of ideas or history of arts approaches and styles of language dominant literary norms. These methods actually are used together and everyone has adequacy in special kind of literary history. In periodization of Persian contemporary literature, some methods and models current in periodization of poetry have been applied identically to periodization of prose. Periodization based upon century, decade and year is the simplest and most mechanical method but sometimes certain centuries in some countries have symbolic and stylistic meaning, and decades were used often for subdivisions of literary history, especially nowadays with fast rhythm of literary change. Periodization according to organic patterns of evolution equates the changes of literary history with the life phases of an organism, and offers an account of birth, mature and death (and sometimes re-birth of literary genres, but this method have

The period-luminosity relation for Cepheids

International Nuclear Information System (INIS)

Brodie, J.P.

1980-01-01

Numerical simulations of the empirical determination of the period-luminosity-colour relation for classical Cepheids are presented. In this study the quantitative effects of random errors, reddening, sample size and the presence of both colour and period cut-offs (imposed by the finite extent of the instability strip) on the observational redetermination of the original relation are evaluated. Both random errors in the photometry and correlated errors in the reddening corrections are shown to have systematic effects. Especially sensitive to these errors is the colour coefficient in the period-luminosity-colour relation, where the ratio of the error to the width of the instability strip is the determining factor. With present observations only broad confidence limits can be placed on present knowledge of the intrinsic period-luminosity-colour relation and/or its variations from galaxy to galaxy. (author)

Broiler adaptation to post-hatching period

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Maiorka Alex

2006-01-01

Full Text Available In the latest years more attention has been given to mechanisms for bird adaptation at post-hatching period by management of environmental conditions and formulations of diets offered during this period when digestive, immune, and thermo-regulating systems suffer slight changes. In post-hatching period, digestive system is anatomically complete, but its functionality is still immature in relation to adult birds. The chick immunity depends on maternal antibodies transferred to egg just before laying. In addition, variations within thermal comfort zone might affect initial development of chick. For example, high temperatures may induce hyperthermia with dehydration, while low temperatures may lead to hypothermia responsible by pulmonary hypertension syndrome. In conclusion, productivity might be enhanced when good conditions are offered to chicks during the period from last embryo development to first days after hatching.

The physiological period length of the human circadian clock in vivo is directly proportional to period in human fibroblasts.

Directory of Open Access Journals (Sweden)

Lucia Pagani

Full Text Available BACKGROUND: Diurnal behavior in humans is governed by the period length of a circadian clock in the suprachiasmatic nuclei of the brain hypothalamus. Nevertheless, the cell-intrinsic mechanism of this clock is present in most cells of the body. We have shown previously that for individuals of extreme chronotype ("larks" and "owls", clock properties measured in human fibroblasts correlated with extreme diurnal behavior. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have measured circadian period in human primary fibroblasts taken from normal individuals and, for the first time, compared it directly with physiological period measured in vivo in the same subjects. Human physiological period length was estimated via the secretion pattern of the hormone melatonin in two different groups of sighted subjects and one group of totally blind subjects, each using different methods. Fibroblast period length was measured via cyclical expression of a lentivirally delivered circadian reporter. Within each group, a positive linear correlation was observed between circadian period length in physiology and in fibroblast gene expression. Interestingly, although blind individuals showed on average the same fibroblast clock properties as sighted ones, their physiological periods were significantly longer. CONCLUSIONS/SIGNIFICANCE: We conclude that the period of human circadian behaviour is mostly driven by cellular clock properties in normal individuals and can be approximated by measurement in peripheral cells such as fibroblasts. Based upon differences among sighted and blind subjects, we also speculate that period can be modified by prolonged unusual conditions such as the total light deprivation of blindness.

Inflation from periodic extra dimensions

Energy Technology Data Exchange (ETDEWEB)

Higaki, Tetsutaro [Department of Physics, Keio University, Kanagawa 223-8522 (Japan); Tatsuta, Yoshiyuki, E-mail: thigaki@rk.phys.keio.ac.jp, E-mail: y_tatsuta@akane.waseda.jp [Department of Physics, Waseda University, Tokyo 169-8555 (Japan)

2017-07-01

We discuss a realization of a small field inflation based on string inspired supergravities. In theories accompanying extra dimensions, compactification of them with small radii is required for realistic situations. Since the extra dimension can have a periodicity, there will appear (quasi-)periodic functions under transformations of moduli of the extra dimensions in low energy scales. Such a periodic property can lead to a UV completion of so-called multi-natural inflation model where inflaton potential consists of a sum of multiple sinusoidal functions with a decay constant smaller than the Planck scale. As an illustration, we construct a SUSY breaking model, and then show that such an inflaton potential can be generated by a sum of world sheet instantons in intersecting brane models on extra dimensions containing orbifold. We show also predictions of cosmic observables by numerical analyzes.

Project 2nd Periodic Report - Section 2

DEFF Research Database (Denmark)

Healy, Mark; Knowles, Emma; Johnstone, Cameron

The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive.......The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive....

Shock dynamics in layered periodic media

KAUST Repository

Ketcheson, David I.; Leveque, Randall J.

2012-01-01

of shock waves in a one-dimensional periodic layered medium by a computational study of time-reversibility and entropy evolution. We find that periodic layered media tend to inhibit shock formation. For small initial conditions and large impedance variation

Periodic vehicle inspection (MOT). [previously: Periodic Vehicle Inspection of cars (MOT).

NARCIS (Netherlands)

2010-01-01

In the 1980s the periodic vehicle inspection (MOT) of various categories of vehicles was introduced in the Netherlands. This fact sheet will discuss the legal framework of this measure and the research carried out into its effects on road safety, also in an international context. For instance, the

A report of three cases of untreated Graves' disease associated with pancytopenia in Malaysia.

Science.gov (United States)

Rafhati, Abdullah Noor; See, Chee Keong; Hoo, Fan Kee; Badrulnizam, Long Bidin Mohamed

2014-01-01

Generally, clinical presentations of Graves' disease range from asymptomatic disease to overt symptomatic hyperthyroidism with heat intolerance, tremor, palpitation, weight loss, and increased appetite. However, atypical presentation of Graves' disease with hematological system involvement, notably pancytopenia, is distinctly uncommon. Hereby, we present and discuss a series of three untreated cases of Graves' disease clinically presented with pancytopenia and the hematological abnormalities that responded well to anti-thyroid treatment. With resolution of the thyrotoxic state, the hematological parameters improved simultaneously. Thus, it is crucial that anti-thyroid treatment be considered in patients with Graves' disease and pancytopenia after a thorough hematological evaluation.

I-131 and thyroid-associated ophthalmopathy

Energy Technology Data Exchange (ETDEWEB)

Rasmussen, Aase Krogh; Nygaard, Birte; Feldt-Rasmussen, Ulla

2000-07-01

Objective: Radioiodine (I-131) used to obtain euthyroidism in thyrotoxic patients is suspected of having a worsening or provoking effect on thyroid-associated ophthalmopathy (TAO), an autoimmune disease closely related to Graves' disease. Design: This review summarises the existing literature and describes risk factors influencing the course of TAO including thyroid function, cigarette smoking and treatment of Graves' hyperthyroidism especially I-131 therapy. Conclusion: It is recommended that patients who may be at a greater risk of worsening ophthalmopathy are considered when choosing the modality of therapy of hyperthyroidism and also in deciding whether prophylactic systemic glucocorticoid treatment is indicated.

A Case of Severe and Recurrent Painless Thyroiditis Requiring Thyroidectomy

Science.gov (United States)

Ishii, Hiroaki; Takei, Masahiro; Sato, Yoshihiko; Ito, Tokiko; Ito, Ken-ichi; Sakai, Yasuhiro; Yumita, Wataru; Suzuki, Satoru; Komatsu, Mitsuhisa

2013-01-01

Objective To report a case of severe and recurrent painless thyroiditis requiring thyroidectomy. Clinical Presentation and Intervention A 47-year-old man who presented with severe thyrotoxicosis was found to have extremely low radioactive iodine uptake, negative TSH receptor antibodies, and normal C-reactive protein; these findings suggested a diagnosis of painless thyroiditis. Due to the severity and recurrence of thyrotoxicosis, surgical resection of the thyroid gland was performed to prevent a thyrotoxic storm. Histological examination revealed typical lymphoid infiltration of the thyroid gland. Conclusion This case illustrates that a patient with painless thyroiditis was successfully treated with surgery. PMID:23182952

Topological imprint for periodic orbits

International Nuclear Information System (INIS)

Martín, Jesús San; Moscoso, Ma José; Gómez, A González

2012-01-01

The more self-crossing points an orbit has the more complex it is. We introduce the topological imprint to characterize crossing points and focus on the period-doubling cascade. The period-doubling cascade topological imprint determines the topological imprint for orbits in chaotic bands. In addition, there is a closer link between this concept and the braids studied by Lettelier et al (2000 J. Phys. A: Math. Gen. 33 1809–25). (paper)

5 CFR 9901.512 - Probationary periods.

Science.gov (United States)

2010-01-01

... 9901.512 Administrative Personnel DEPARTMENT OF DEFENSE HUMAN RESOURCES MANAGEMENT AND LABOR RELATIONS SYSTEMS (DEPARTMENT OF DEFENSE-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF DEFENSE NATIONAL SECURITY... Probationary periods. (a) Initial probationary period. (1) An employee who is given a career, career...

Period Variations for the Cepheid VZ Cyg

Science.gov (United States)

Sirorattanakul, Krittanon; Engle, Scott; Pepper, Joshua; Wells, Mark; Laney, Clifton D.; Rodriguez, Joseph E.; Stassun, Keivan G.

2017-12-01

The Cepheid Period-Luminosity law is a key rung on the extragalactic distance ladder. However, numerous Cepheids are known to undergo period variations. Monitoring, refining, and understanding these period variations allows us to better determine the parameters of the Cepheids themselves and of the instability strip in which they reside, and to test models of stellar evolution. VZ Cyg, a classical Cepheid pulsating at ˜4.864 days, has been observed for over 100 years. Combining data from literature observations, the Kilodegree Extremely Little Telescope (KELT) transit survey, and new targeted observations with the Robotically Controlled Telescope (RCT) at Kitt Peak, we find a period change rate of dP/dt = -0.0642 ± 0.0018 s yr-1. However, when only the recent observations are examined, we find a much higher period change rate of dP/dt = -0.0923 ± 0.0110 s yr-1. This higher rate could be due to an apparent long-term (P ≈ 26.5 years) cyclic period variation. The possible interpretations of this single Cepheid’s complex period variations underscore both the need to regularly monitor pulsating variables and the important benefits that photometric surveys such as KELT can have on the field. Further monitoring of this interesting example of Cepheid variability is recommended to confirm and better understand the possible cyclic period variations. Further, Cepheid timing analyses are necessary to fully understand their current behaviors and parameters, as well as their evolutionary histories.

Viral infection model with periodic lytic immune response

International Nuclear Information System (INIS)

Wang Kaifa; Wang Wendi; Liu Xianning

2006-01-01

Dynamical behavior and bifurcation structure of a viral infection model are studied under the assumption that the lytic immune response is periodic in time. The infection-free equilibrium is globally asymptotically stable when the basic reproductive ratio of virus is less than or equal to one. There is a non-constant periodic solution if the basic reproductive ratio of the virus is greater than one. It is found that period doubling bifurcations occur as the amplitude of lytic component is increased. For intermediate birth rates, the period triplication occurs and then period doubling cascades proceed gradually toward chaotic cycles. For large birth rate, the period doubling cascade proceeds gradually toward chaotic cycles without the period triplication, and the inverse period doubling can be observed. These results can be used to explain the oscillation behaviors of virus population, which was observed in chronic HBV or HCV carriers

Dispersion Differences and Consistency of Artificial Periodic Structures.

Science.gov (United States)

Cheng, Zhi-Bao; Lin, Wen-Kai; Shi, Zhi-Fei

2017-10-01

Dispersion differences and consistency of artificial periodic structures, including phononic crystals, elastic metamaterials, as well as periodic structures composited of phononic crystals and elastic metamaterials, are investigated in this paper. By developing a K(ω) method, complex dispersion relations and group/phase velocity curves of both the single-mechanism periodic structures and the mixing-mechanism periodic structures are calculated at first, from which dispersion differences of artificial periodic structures are discussed. Then, based on a unified formulation, dispersion consistency of artificial periodic structures is investigated. Through a comprehensive comparison study, the correctness for the unified formulation is verified. Mathematical derivations of the unified formulation for different artificial periodic structures are presented. Furthermore, physical meanings of the unified formulation are discussed in the energy-state space.

Existence and global attractivity of positive periodic solutions of periodic n-species Lotka-Volterra competition systems with several deviating arguments.

Science.gov (United States)

Fan, M; Wang, K; Jiang, D

1999-08-01

In this paper, we study the existence and global attractivity of positive periodic solutions of periodic n-species Lotka-Volterra competition systems. By using the method of coincidence degree and Lyapunov functional, a set of easily verifiable sufficient conditions are derived for the existence of at least one strictly positive (componentwise) periodic solution of periodic n-species Lotka-Volterra competition systems with several deviating arguments and the existence of a unique globally asymptotically stable periodic solution with strictly positive components of periodic n-species Lotka-Volterra competition system with several delays. Some new results are obtained. As an application, we also examine some special cases of the system we considered, which have been studied extensively in the literature. Some known results are improved and generalized.

Periodic and secular changes in SS 433

International Nuclear Information System (INIS)

Collins, G.W.; Newsom, G.H.

1983-01-01

The recent history of SS 433 is reviewed with particular attention being given to the discovery of the periodic phenomena displayed by this object. Several periods ranging from days to months are established as being present in the spectrum of the ''moving'' lines as well as in other aspects of the emission from the object. In addition evidence for secular change in some of the defining parameters of the system is presented. Although these secular changes may eventually prove to be periodic on a rather long time scale, some interpretation of both the periodic and secular phenomena is possible. It is shown that it is possible to interpret all the known periodic phenomena in terms of a processing object responding to the time-varying torques that one would expect in a binary system

38 CFR 3.2 - Periods of war.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Periods of war. 3.2..., Compensation, and Dependency and Indemnity Compensation General § 3.2 Periods of war. This section sets forth the beginning and ending dates of each war period beginning with the Indian wars. Note that the term...

Periodicity, the Canon and Sport

Directory of Open Access Journals (Sweden)

Thomas F. Scanlon

2015-10-01

Full Text Available The topic according to this title is admittedly a broad one, embracing two very general concepts of time and of the cultural valuation of artistic products. Both phenomena are, in the present view, largely constructed by their contemporary cultures, and given authority to a great extent from the prestige of the past. The antiquity of tradition brings with it a certain cachet. Even though there may be peripheral debates in any given society which question the specifics of periodization or canonicity, individuals generally accept the consensus designation of a sequence of historical periods and they accept a list of highly valued artistic works as canonical or authoritative. We will first examine some of the processes of periodization and of canon-formation, after which we will discuss some specific examples of how these processes have worked in the sport of two ancient cultures, namely Greece and Mesoamerica.

The Dynamic Multi-Period Vehicle Routing Problem

DEFF Research Database (Denmark)

Wen, Min; Cordeau, Jean-Francois; Laporte, Gilbert

This paper considers the Dynamic Multi-Period Vehicle Routing Problem which deals with the distribution of orders from a depot to a set of customers over a multi-period time horizon. Customer orders and their feasible service periods are dynamically revealed over time. The objectives are to minim......This paper considers the Dynamic Multi-Period Vehicle Routing Problem which deals with the distribution of orders from a depot to a set of customers over a multi-period time horizon. Customer orders and their feasible service periods are dynamically revealed over time. The objectives...... are to minimize total travel costs and customer waiting, and to balance the daily workload over the planning horizon. This problem originates from a large distributor operating in Sweden. It is modeled as a mixed integer linear program, and solved by means of a three-phase heuristic that works over a rolling...... planning horizon. The multi-objective aspect of the problem is handled through a scalar technique approach. Computational results show that our solutions improve upon those of the Swedish distributor....

Painful periods (dysmenorrhea) (image)

Science.gov (United States)

Primary dysmenorrhea is a normal cramping of the lower abdomen caused by hormone-induced uterine contractions before the period. Secondary dysmenorrhea may be caused by abnormal conditions such as ...

Discontinuous Spirals of Stable Periodic Oscillations

DEFF Research Database (Denmark)

Sack, Achim; Freire, Joana G.; Lindberg, Erik

2013-01-01

We report the experimental discovery of a remarkable organization of the set of self-generated periodic oscillations in the parameter space of a nonlinear electronic circuit. When control parameters are suitably tuned, the wave pattern complexity of the periodic oscillations is found to increase...

Selecting Full-Text Undergraduate Periodicals Databases.

Science.gov (United States)

Still, Julie M.; Kassabian, Vibiana

1999-01-01

Examines how libraries and librarians can compare full-text general periodical indices, using ProQuest Direct, Periodical Abstracts (via Ovid), and EBSCOhost as examples. Explores breadth and depth of coverage; manipulation of results (email/download/print); ease of use (searching); and indexing quirks. (AEF)

Almost periodic Hamiltonians: an algebraic approach

International Nuclear Information System (INIS)

Bellissard, J.

1981-07-01

We develop, by analogy with the study of periodic potential, an algebraic theory for almost periodic hamiltonians, leading to a generalized Bloch theorem. This gives rise to results concerning the spectral measures of these operators in terms of those of the corresponding Bloch hamiltonians

Variable-Period Undulators For Synchrotron Radiation

Science.gov (United States)

Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

2005-02-22

A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high-energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

Variable-Period Undulators for Synchrotron Radiation

Energy Technology Data Exchange (ETDEWEB)

Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

2005-02-22

A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

Convectons in periodic and bounded domains

International Nuclear Information System (INIS)

Mercader, Isabel; Batiste, Oriol; Alonso, Arantxa; Knobloch, Edgar

2010-01-01

Numerical continuation is used to compute spatially localized convection in a binary fluid with no-slip laterally insulating boundary conditions and the results are compared with the corresponding ones for periodic boundary conditions (PBC). The change in the boundary conditions produces a dramatic change in the snaking bifurcation diagram that describes the organization of localized states with PBC: the snaking branches turn continuously into a large amplitude state that resembles periodic convection with defects at the sidewalls. Odd parity convectons are more affected by the boundary conditions since the sidewalls suppress the horizontal pumping action that accompanies these states in spatially periodic domains.

Convectons in periodic and bounded domains

Energy Technology Data Exchange (ETDEWEB)

Mercader, Isabel; Batiste, Oriol; Alonso, Arantxa [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, Barcelona (Spain); Knobloch, Edgar [Department of Physics, University of California, Berkeley, CA 94720 (United States)

2010-04-15

Numerical continuation is used to compute spatially localized convection in a binary fluid with no-slip laterally insulating boundary conditions and the results are compared with the corresponding ones for periodic boundary conditions (PBC). The change in the boundary conditions produces a dramatic change in the snaking bifurcation diagram that describes the organization of localized states with PBC: the snaking branches turn continuously into a large amplitude state that resembles periodic convection with defects at the sidewalls. Odd parity convectons are more affected by the boundary conditions since the sidewalls suppress the horizontal pumping action that accompanies these states in spatially periodic domains.

The period-age relation for cepheids

International Nuclear Information System (INIS)

Efremov, Yu.N.

1978-01-01

The list of 119 cepheid-members of 55 clusters and associations of the Magellanic Clouds, the Galaxy, and M31 is given. The period-age relation is found from the data on 64 cepheids in 29 clusters for which the age determinations are available, the ages of extragalactic clusters were determined mainly from their integral colours. The U-B colours are found to be of much better age parameters than the B-V ones. The composite period-age relation agrees well with the theoretical one. The observed dispersion of the period-age relation leads to an estimate of the age dispersion about 1x10 7 years in the associations. Some peculiarities of the cepheids with the shortest periods amongst others in the same clusters are probably explained if they are overtone pulsators. The period-age relation may be used for an investigation of the recent history of star formation in the galaxies. This relation allows to determine the age gradient across the spiral arm in M31 which is in agreement with the density wave theory predictions. The distribution of cepheids in our Galaxy and neighbouring galaxies is consistent with the conception of star formation lasting for some dozen million years in cells with a dimension of some hundreds of parsecs

Period Changes of 23 Field RR Lyrae Stars

Directory of Open Access Journals (Sweden)

Soo-Chang Rey

1994-12-01

Full Text Available The secular period behavior of 23 field RR Lyrae stars is studied in order to determine if the observed period changes could be attributed, at least in the mean, to stellar evolution. The sample of stars is subdivided into two Oosterhoff groups based on the metallicity and period-shift. Despite the small sample size, we found a distinct bias toward positive period changes in the group variables. The period changes of the group variables in globular clusters. This provides yet another support for the Lee, Demarque, and Zinn(1990 evolutionary models of RR Lyrae stars and their explanation of the Sandage period-shift effect.

The Periodic Table CD.

Science.gov (United States)

Banks, Alton J.; Holmes, Jon L.

1995-01-01

Describes the characteristics of the digitized version of The Periodic Table Videodisc. Provides details about the organization of information and access to the data via Macintosh and Windows computers. (DDR)

46 CFR 403.115 - Accounting period.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Accounting period. 403.115 Section 403.115 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE UNIFORM ACCOUNTING SYSTEM General § 403.115 Accounting period. Each Association subject to this part shall maintain...

David's Understanding of Functions and Periodicity

Science.gov (United States)

Gerson, Hope

2008-01-01

This is a study of David, a senior enrolled in a high school precalculus course. David's understandings of functions and periodicity was explored, through clinical interviews and contextualized through classroom observations. Although David's precalculus class was traditional his understanding of periodic functions was unconventional David engaged…

Multi-Period Trading via Convex Optimization

DEFF Research Database (Denmark)

Boyd, Stephen; Busseti, Enzo; Diamond, Steve

2017-01-01

We consider a basic model of multi-period trading, which can be used to evaluate the performance of a trading strategy. We describe a framework for single-period optimization, where the trades in each period are found by solving a convex optimization problem that trades off expected return, risk......, transaction cost and holding cost such as the borrowing cost for shorting assets. We then describe a multi-period version of the trading method, where optimization is used to plan a sequence of trades, with only the first one executed, using estimates of future quantities that are unknown when the trades....... In this paper, we do not address a critical component in a trading algorithm, the predictions or forecasts of future quantities. The methods we describe in this paper can be thought of as good ways to exploit predictions, no matter how they are made. We have also developed a companion open-source software...

Periodic and in-service inspection programs

International Nuclear Information System (INIS)

Dinu, M.

2000-01-01

Periodic and in-service inspection programs for Cernavoda NPP consists of periodic inspections of CANDU NPP components CSAN N-285.4 and CSAN N-285.4, in-service inspections and repair and modifications general inspection. Periodic inspection program document (PIPD) determines the systems and components subject to inspection, the category of the inspection, techniques, areas and other details.The current status of the inspection programs is presented, including containment , erosion/corrosion, pressure vessel support and snubbers, main steam lines inspection programs. Qualification program in Cernavoda NPP involves equipment qualification in the on-site laboratory, yearly certification, special equipment qualification in the National Institute of Metrology. All procedures are approved by the ISCIR (regulatory body for pressure vessel and lifting equipment) and CNCAN (National Commission on Nuclear Activities Control). Qualification of the personnel is performed according to the ISCIR Technical prescription CR 11/82 for up to 3 year period. Final qualification and licensing is performed by CNCAN

46 CFR 61.40-6 - Periodic safety tests.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Periodic safety tests. 61.40-6 Section 61.40-6 Shipping... INSPECTIONS Design Verification and Periodic Testing of Vital System Automation § 61.40-6 Periodic safety tests. (a) Periodic Safety tests must demonstrate the proper operation of the primary and alternate...

How periodic are terahertz quantum cascade lasers?

International Nuclear Information System (INIS)

Kubis, T; Vogl, P

2009-01-01

We apply a novel non-equilibrium Green's function method for open quantum devices to analyze quantum cascade lasers. We find the carrier distribution in typical resonant phonon THz-QCLs to develop a periodicity that differs from the geometric periodicity of the QCL. We propose a design improvement that thermalizes electrons at threshold bias and thereby pins the electron density to the QCL periodicity.

42 CFR 409.60 - Benefit periods.

Science.gov (United States)

2010-10-01

... 42 Public Health 2 2010-10-01 2010-10-01 false Benefit periods. 409.60 Section 409.60 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM HOSPITAL INSURANCE BENEFITS Scope of Hospital Insurance Benefits § 409.60 Benefit periods. (a) When benefit...

12 CFR 226.7 - Periodic statement.

Science.gov (United States)

2010-01-01

... consumer with a periodic statement that discloses the following items, to the extent applicable: (a... convenience of the user, the revised text is set forth as follows: § 226.7 Periodic statement. (a) Rules... consumers may obtain from the creditor more information about the balance computation method and how...

Improved nonparametric inference for multiple correlated periodic sequences

KAUST Repository

Sun, Ying

2013-08-26

This paper proposes a cross-validation method for estimating the period as well as the values of multiple correlated periodic sequences when data are observed at evenly spaced time points. The period of interest is estimated conditional on the other correlated sequences. An alternative method for period estimation based on Akaike\\'s information criterion is also discussed. The improvement of the period estimation performance is investigated both theoretically and by simulation. We apply the multivariate cross-validation method to the temperature data obtained from multiple ice cores, investigating the periodicity of the El Niño effect. Our methodology is also illustrated by estimating patients\\' cardiac cycle from different physiological signals, including arterial blood pressure, electrocardiography, and fingertip plethysmograph.

Global Scale Periodic Responses in Saturn’s Magnetosphere

Science.gov (United States)

Jia, Xianzhe; Kivelson, Margaret G.

2017-10-01

Despite having an axisymmetric internal magnetic field, Saturn’s magnetosphere exhibits periodic modulations in a variety of properties at periods close to the planetary rotation period. While the source of the periodicity remains unidentified, it is evident from Cassini observations that much of Saturn’s magnetospheric structure and dynamics is dominated by global-scale responses to the driving source of the periodicity. We have developed a global MHD model in which a rotating field-aligned current system is introduced by imposing vortical flows in the high-latitude ionosphere in order to simulate the magnetospheric periodicities. The model has been utilized to quantitatively characterize various periodic responses in the magnetosphere, such as the displacement of the magnetopause and bow shock and flapping of the tail plasma sheet, all of which show quantitative agreement with Cassini observations. One of our model predictions is periodic release of plasmoids in the tail that occurs preferentially in the midnight-to-dawn local time sector during each rotation cycle. Here we present detailed analysis of the periodic responses seen in our simulations focusing on the properties of plasmoids predicted by the model, including their spatial distribution, occurrence frequency, and mass loss rate. We will compare these modeled parameters with published Cassini observations, and discuss their implications for interpreting in-situ measurements.

Diffraction Theory and Almost Periodic Distributions

Science.gov (United States)

Strungaru, Nicolae; Terauds, Venta

2016-09-01

We introduce and study the notions of translation bounded tempered distributions, and autocorrelation for a tempered distribution. We further introduce the spaces of weakly, strongly and null weakly almost periodic tempered distributions and show that for weakly almost periodic tempered distributions the Eberlein decomposition holds. For translation bounded measures all these notions coincide with the classical ones. We show that tempered distributions with measure Fourier transform are weakly almost periodic and that for this class, the Eberlein decomposition is exactly the Fourier dual of the Lebesgue decomposition, with the Fourier-Bohr coefficients specifying the pure point part of the Fourier transform. We complete the project by looking at few interesting examples.

20 CFR 410.501 - Payment periods.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Payment periods. 410.501 Section 410.501 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Payment of Benefits § 410.501 Payment periods. Benefits are paid to...

24 CFR 221.775 - Option period.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Option period. 221.775 Section 221.775 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... § 221.775 Option period. The mortgagee may exercise its option to assign within one year following the...

28 CFR 524.75 - Periodic review.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Periodic review. 524.75 Section 524.75... TRANSFER CLASSIFICATION OF INMATES Central Inmate Monitoring (CIM) System § 524.75 Periodic review. The Warden shall ensure that the status of an inmate's CIM assignment is considered at each program review...

20 CFR 655.205 - Recruitment period.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Recruitment period. 655.205 Section 655.205... FOREIGN WORKERS IN THE UNITED STATES Labor Certification Process for Logging Employment and Non-H-2A Agricultural Employment § 655.205 Recruitment period. (a) If the OFLC Administrator determines that the...

Study of possible chaotic, quasi-periodic and periodic structures in quantum dusty plasma

International Nuclear Information System (INIS)

Ghosh, Uday Narayan; Chatterjee, Prasanta; Roychoudhury, Rajkumar

2014-01-01

Existence of chaotic, quasi-periodic, and periodic structures of dust-ion acoustic waves is studied in quantum dusty plasmas through dynamical system approach. A system of coupled differential equations is derived from the fluid model and subsequently, variational matrix is obtained. The characteristic equation is obtained at the equilibrium point, and the behavior of nonlinear waves is studied numerically using Runge-Kutta method. The behavior of the dynamical system changes significantly when any of plasma parameters, such as the dust concentration parameter, temperature ratio, or the quantum diffraction parameter, is varied. The change of the characteristic of solution of the system is extensively studied. It is found that the system changes its behavior from chaotic pattern to limit cycle behavior

Deciphering Periodic Methanol Masers

Science.gov (United States)

Stecklum, Bringfried; Caratti o Garatti, Alessio; Henning, Thomas; Hodapp, Klaus; Hopp, Ulrich; Kraus, Alex; Linz, Hendrik; Sanna, Alberto; Sobolev, Andrej; Wolf, Verena

2018-05-01

Impressive progress has been made in recent years on massive star formation, yet the involved high optical depths even at submm/mm wavelengths make it difficult to reveal its details. Recently, accretion bursts of massive YSOs have been identified to cause flares of Class II methanol masers (methanol masers for short) due to enhanced mid-IR pumping. This opens a new window to protostellar accretion variability, and implies that periodic methanol masers hint at cyclic accretion. Pinning down the cause of the periodicity requires joint IR and radio monitoring. We derived the first IR light curve of a periodic maser host from NEOWISE data. The source, G107.298+5.639, is an intermediate-mass YSO hosting methanol and water masers which flare every 34.5 days. Our recent joint K-band and radio observations yielded first but marginal evidence for a phase lag between the rise of IR and maser emission, respectively, and revealed that both NEOWISE and K-band light curves are strongly affected by the light echo from the ambient dust. Both the superior resolution of IRAC over NEOWISE and the longer wavelengths compared to our ground-based imaging are required to inhibit the distractive contamination by the light echo. Thus, we ask for IRAC monitoring of G107 to cover one flare cycle, in tandem with 100-m Effelsberg and 2-m Wendelstein radio and NIR observations to obtain the first high-quality synoptic measurements of this kind of sources. The IR-maser phase lag, the intrinsic shape of the IR light curves and their possible color variation during the cycle allow us to constrain models for the periodic maser excitation. Since methanol masers are signposts of intermediate-mass and massive YSOs, deciphering their variability offers a clue to the dynamics of the accretion-mediated growth of massive stars and their feedback onto the immediate natal environment. The Spitzer light curve of such a maser-hosting YSO would be a legacy science product of the mission.

How periodic are terahertz quantum cascade lasers?

Energy Technology Data Exchange (ETDEWEB)

Kubis, T; Vogl, P, E-mail: tillmann.kubis@wsi.tum.d [Walter Schottky Institute, Technische Universitaet Muenchen, Am Coulombwall 3, 85748 Garching (Germany)

2009-11-15

We apply a novel non-equilibrium Green's function method for open quantum devices to analyze quantum cascade lasers. We find the carrier distribution in typical resonant phonon THz-QCLs to develop a periodicity that differs from the geometric periodicity of the QCL. We propose a design improvement that thermalizes electrons at threshold bias and thereby pins the electron density to the QCL periodicity.

mPeriod2 Brdm1 and other single Period mutant mice have normal food anticipatory activity.

Science.gov (United States)

Pendergast, Julie S; Wendroth, Robert H; Stenner, Rio C; Keil, Charles D; Yamazaki, Shin

2017-11-14

Animals anticipate the timing of food availability via the food-entrainable oscillator (FEO). The anatomical location and timekeeping mechanism of the FEO are unknown. Several studies showed the circadian gene, Period 2, is critical for FEO timekeeping. However, other studies concluded that canonical circadian genes are not essential for FEO timekeeping. In this study, we re-examined the effects of the Per2 Brdm1 mutation on food entrainment using methods that have revealed robust food anticipatory activity in other mutant lines. We examined food anticipatory activity, which is the output of the FEO, in single Period mutant mice. Single Per1, Per2, and Per3 mutant mice had robust food anticipatory activity during restricted feeding. In addition, we found that two different lines of Per2 mutant mice (ldc and Brdm1) anticipated restricted food availability. To determine if FEO timekeeping persisted in the absence of the food cue, we assessed activity during fasting. Food anticipatory (wheel-running) activity in all Period mutant mice was also robust during food deprivation. Together, our studies demonstrate that the Period genes are not necessary for the expression of food anticipatory activity.

26 CFR 31.3401(b)-1 - Payroll period.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Payroll period. 31.3401(b)-1 Section 31.3401(b... Collection of Income Tax at Source § 31.3401(b)-1 Payroll period. (a) The term payroll period means the... elapsed and receives the remainder at the end of the week, the payroll period is still the calendar week...

Distinct functions of Period2 and Period3 in the mouse circadian system revealed by in vitro analysis.

Directory of Open Access Journals (Sweden)

Julie S Pendergast

2010-01-01

Full Text Available The mammalian circadian system, which is composed of a master pacemaker in the suprachiasmatic nuclei (SCN as well as other oscillators in the brain and peripheral tissues, controls daily rhythms of behavior and physiology. Lesions of the SCN abolish circadian rhythms of locomotor activity and transplants of fetal SCN tissue restore rhythmic behavior with the periodicity of the donor's genotype, suggesting that the SCN determines the period of the circadian behavioral rhythm. According to the model of timekeeping in the SCN, the Period (Per genes are important elements of the transcriptional/translational feedback loops that generate the endogenous circadian rhythm. Previous studies have investigated the functions of the Per genes by examining locomotor activity in mice lacking functional PERIOD proteins. Variable behavioral phenotypes were observed depending on the line and genetic background of the mice. In the current study we assessed both wheel-running activity and Per1-promoter-driven luciferase expression (Per1-luc in cultured SCN, pituitary, and lung explants from Per2(-/- and Per3(-/- mice congenic with the C57BL/6J strain. We found that the Per2(-/- phenotype is enhanced in vitro compared to in vivo, such that the period of Per1-luc expression in Per2(-/- SCN explants is 1.5 hours shorter than in Per2+/+ SCN, while the free-running period of wheel-running activity is only 11 minutes shorter in Per2(-/- compared to Per2+/+ mice. In contrast, circadian rhythms in SCN explants from Per3(-/- mice do not differ from Per3+/+ mice. Instead, the period and phase of Per1-luc expression are significantly altered in Per3(-/- pituitary and lung explants compared to Per3+/+ mice. Taken together these data suggest that the function of each Per gene may differ between tissues. Per2 appears to be important for period determination in the SCN, while Per3 participates in timekeeping in the pituitary and lung.

18 CFR 367.5 - Accounting period.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Accounting period. 367.5 Section 367.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Instructions § 367.5 Accounting period. Each service company must keep its books on a monthly basis so that for...

50 CFR 424.21 - Periodic review.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Periodic review. 424.21 Section 424.21... SPECIES AND DESIGNATING CRITICAL HABITAT Revision of the Lists § 424.21 Periodic review. At least once every 5 years, the Secretary shall conduct a review of each listed species to determine whether it...

12000 rotation periods of Kepler stars (Nielsen+, 2013)

DEFF Research Database (Denmark)

Nielsen, M. B.; Gizon, L.; Schunker, H.

2013-01-01

Rotation periods of 12253 stars in the Kepler field. The periods are determined by the brightness variations, from star spots or active regions, in the light curves of the white light photometry obtained by the Kepler spacecraft. The median absolute deviation from the median (MAD) of the periods...... shows the scatter of periods for each star, over 6 or more (out of 8 analyzed) Kepler quarters. The g-r color index, E(B-V), radius, surface gravity, and effective temperature are from the Kepler Input Catalog (KIC). Column 9 (TF) indicates whether or not the msMAP data for a given star satisfies...... the selection criteria described in section 2. Of these, there are 86 stars with periods from the msMAP data that differ from the period derived from the PDCMAP data by more than one frequency resolution element (1/90d-1). For these stars the msMAP periods are therefore given in column 10 as a none-zero value...

The "sticking period" in a maximum bench press.

Science.gov (United States)

van den Tillaar, Roland; Ettema, Gertjan

2010-03-01

The purpose of this study was to examine muscle activity and three-dimensional kinematics in the ascending phase of a successful one-repetition maximum attempt in bench press for 12 recreational weight-training athletes, with special attention to the sticking period. The sticking period was defined as the first period of deceleration of the upward movement (i.e. from the highest barbell velocity until the first local lowest barbell velocity). All participants showed a sticking period during the upward movement that started about 0.2 s after the initial upward movement, and lasted about 0.9 s. Electromyography revealed that the muscle activity of the prime movers changed significantly from the pre-sticking to the sticking and post-sticking periods. A possible mechanism for the existence of the sticking period is the diminishing potentiation of the contractile elements during the upward movement together with the limited activity of the pectoral and deltoid muscles during this period.

Vaginal bleeding between periods

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/003156.htm Vaginal bleeding between periods To use the sharing features ... this page, please enable JavaScript. This article discusses vaginal bleeding that occurs between a woman's monthly menstrual ...

On almost-periodic points of a topological Markov chain

International Nuclear Information System (INIS)

Bogatyi, Semeon A; Redkozubov, Vadim V

2012-01-01

We prove that a transitive topological Markov chain has almost-periodic points of all D-periods. Moreover, every D-period is realized by continuously many distinct minimal sets. We give a simple constructive proof of the result which asserts that any transitive topological Markov chain has periodic points of almost all periods, and study the structure of the finite set of positive integers that are not periods.

Flood rich periods, flood poor periods and the need to look beyond instrumental records

Science.gov (United States)

Lane, S. N.

2009-04-01

For many, the later 20th Century and early 21st Century has become synonymous with a growing experience of flood risk. Scientists, politicians and the media have ascribed this to changing climate and there are good hypothetical reasons for human-induced climate change to be impacting upon the magnitude and frequency of extreme weather events. In this paper, I will interrogate this claim more carefully, using the UK's instrumental records of river flow, most of which begin after 1960, but a smaller number of which extend back into the 19th Century. Those records that extent back to the 19th Century suggest that major flood events tend to cluster into periods that are relatively flood rich and relatively flood poor, most notably in larger drainage basins: i.e. there is a clear scale issue. The timing (inset, duration, termination) of these periods varies systematically by region although there is a marked flood poor period for much of the UK during the late 1960s, 1970s and 1980s. It follows that at least some of the current experience of flooding, including why it has taken so many policy-makers and flood victims by surprise, may reflect a transition from a flood poor to a flood rich period, exacerbated by possible climate change impacts. These results point to the need to rethink how we think through what drives flood risk. First, it points to the need to look at some of the fundamental oscillations in core atmospheric drivers, such as the North Atlantic Multidecadal Oscillation, in explaining what drives flood risk. Consideration of precipitation, as opposed to river flow, is more advanced in this respect, and those of us working in rivers need to engage much more thoughtfully with atmospheric scientists. Second, it points to the severe inadequacies in using records of only a few decades duration. Even where these are pooled across adjacent sub-catchments, there is likely to be a severe bias in the estimation of flood return periods when we look at instrumental

Prognosis following cancer surgery during holiday periods.

Science.gov (United States)

Lagergren, Jesper; Mattsson, Fredrik; Lagergren, Pernilla

2017-11-15

Surgery is the mainstay curative treatment in most cancer. We aimed to test the new hypothesis that cancer surgery performed during holiday periods is associated with worse long-term prognosis than for non-holiday periods. This nationwide Swedish population-based cohort study included 228,927 patients during 1997-2014 who underwent elective resectional surgery for a cancer where the annual number of resections was over 100. The 16 eligible cancer sites were grouped into 10 cancer groups. The exposure, holiday periods, was classified as wide (14-weeks) or narrow (7-weeks). Surgery conducted inside versus outside holiday periods was compared regarding overall disease-specific (main outcome) and overall all-cause (secondary outcome) mortality. Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, sex, comorbidity, hospital volume, calendar period and tumor stage. Surgery conducted during wide and narrow holiday periods were associated with increased HRs of disease-specific mortality for cancer of the breast (HR 1.08, 95% CI 1.03-1.13 and HR 1.06, 95% CI 1.01-1.12) and possibly of cancer of the liver-pancreas-bile ducts (HR 1.09, 95% CI 0.99-1.20 and HR 1.12, 95% CI 0.99-1.26). Sub-groups with cancer of the colon-rectum, head-and-neck, prostate, kidney-urine bladder and thyroid also experienced statistically significantly worse prognosis following surgery conducted during holiday periods. No influence of surgery during holiday was detected for cancer of the esophagus-stomach, lung or ovary-uterus. All-cause HRs were similar to the disease-specific HRs. The prognosis following cancer surgery might not be fully maintained during holiday periods for all cancer sites. © 2017 UICC.

Enhanced diffusion with abnormal temperature dependence in underdamped space-periodic systems subject to time-periodic driving

Science.gov (United States)

Marchenko, I. G.; Marchenko, I. I.; Zhiglo, A. V.

2018-01-01

We present a study of the diffusion enhancement of underdamped Brownian particles in a one-dimensional symmetric space-periodic potential due to external symmetric time-periodic driving with zero mean. We show that the diffusivity can be enhanced by many orders of magnitude at an appropriate choice of the driving amplitude and frequency. The diffusivity demonstrates abnormal (decreasing) temperature dependence at the driving amplitudes exceeding a certain value. At any fixed driving frequency Ω normal temperature dependence of the diffusivity is restored at low enough temperatures, T oscillation frequency at the potential minimum, the diffusivity is shown to decrease with Ω according to a power law, with the exponent related to the transient superdiffusion exponent. This behavior is found similar for the cases of sinusoidal in time and piecewise constant periodic ("square") driving.

On periodic orbits in discrete-time cascade systems

Directory of Open Access Journals (Sweden)

Huimin Li

2006-01-01

Full Text Available We present some results on existence, minimum period, number of periodic orbits, and stability of periodic orbits in discrete-time cascade systems. Some examples are presented to illustrate these results.

El pacto periodístico

OpenAIRE

Ma. de Lourdes Romero Álvarez

2002-01-01

En este artículo se plantea una de las cuestiones fundamentales sobre las que se realiza la actividad periodística y que la autora ha llamado el pacto periodístico. El pacto, celebrado entre el periodista y sus lectores, consiste en que el emisor expresa lo que sucedió tal y como lo vio y el destinatario acepta lo expresado en las mismas condiciones. El compromiso entre ambos participantes los obliga a saber y cumplir con lo estipulado en el contrato, para evitar que alguna de ...

Sigmoid Volvulus Complicating Postpartum Period

Directory of Open Access Journals (Sweden)

Kelsey E. Ward

2017-01-01

Full Text Available Background. Sigmoid volvulus is a rare complication of pregnancy and the puerperium. Case. A 19-year-old patient, gravida 1 para 0 at 41 0/7 weeks of gestation, admitted for late-term induction of labor underwent an uncomplicated primary low transverse cesarean delivery for arrest of descent. Her postoperative period was complicated by sudden onset of abdominal pain and the ultimate diagnosis of sigmoid volvulus. Conclusion. Prompt surgical evaluation of an acute abdomen in the postpartum period is essential; delayed diagnosis and treatment can lead to significant maternal morbidity and mortality.

Attractors for discrete periodic dynamical systems

Science.gov (United States)

John E. Franke; James F. Selgrade

2003-01-01

A mathematical framework is introduced to study attractors of discrete, nonautonomous dynamical systems which depend periodically on time. A structure theorem for such attractors is established which says that the attractor of a time-periodic dynamical system is the unin of attractors of appropriate autonomous maps. If the nonautonomous system is a perturbation of an...

Theory of Periodic Conjugate Heat Transfer

CERN Document Server

Zudin, Yuri B

2012-01-01

This book presents the theory of periodic conjugate heat transfer in a detailed way. The effects of thermophysical properties and geometry of a solid body on the commonly used and experimentally determined heat transfer coefficient are analytically presented from a general point of view. The main objective of the book is a simplified description of the interaction between a solid body and a fluid as a boundary value problem of the heat conduction equation for the solid body. At the body surface, the true heat transfer coefficient is composed of two parts: the true mean value resulting from the solution of the steady state heat transfer problem and a periodically variable part, the periodic time and length to describe the oscillatory hydrodynamic effects. The second edition is extended by (i) the analysis of stability boundaries in helium flow at supercritical conditions in a heated channel with respect to the interaction between a solid body and a fluid; (ii) a periodic model and a method of heat transfer sim...

Optimization on replacement period of plant equipment

International Nuclear Information System (INIS)

Kasai, Masao; Asano, Hiromi

2002-01-01

Optimization of the replacement period of plant equipment is one of the main items to rationalize the activities on plant maintenance. There are several models to replace the equipment and the formulations for optimizing the replacement period are different among these models. In this study, we calculated the optimum replacement periods for some equipment parts based on the replacement models and found that the optimum solutions are not so largely differ from the replacement models as far as the replacement period is not so large. So we will be able to use the most usable model especially in the early phase of rationalization on plant maintenance, since there are large uncertainties in data for optimization. (author)

Global bioevents and the question of periodicity

Science.gov (United States)

Sepkoski, J. John

The hypothesis of periodicity in extinction is an empirical claim that extinction events, while variable in magnitude, are regular in timing and therefore are serially dependent upon some single, ultimate cause with clocklike behavior. This hypothesis is controversal, in part because of questions regarding the identity and timing of certain extinction events and because of speculations concerning possible catastrophic extraterrestrial forcing mechanisms. New data on extinctions of marine animal genera are presented that display a high degree of periodicity in the Mesozoic and Cenozoic as well as a suggestion of nonstationary periodicity in the late Paleozoic. However, no periodicity is evident among the as yet poorly documented extinction events of the early and middle Paleozoic.

Rogue periodic waves of the modified KdV equation

Science.gov (United States)

Chen, Jinbing; Pelinovsky, Dmitry E.

2018-05-01

Rogue periodic waves stand for rogue waves on a periodic background. Two families of travelling periodic waves of the modified Korteweg–de Vries (mKdV) equation in the focusing case are expressed by the Jacobian elliptic functions dn and cn. By using one-fold and two-fold Darboux transformations of the travelling periodic waves, we construct new explicit solutions for the mKdV equation. Since the dn-periodic wave is modulationally stable with respect to long-wave perturbations, the new solution constructed from the dn-periodic wave is a nonlinear superposition of an algebraically decaying soliton and the dn-periodic wave. On the other hand, since the cn-periodic wave is modulationally unstable with respect to long-wave perturbations, the new solution constructed from the cn-periodic wave is a rogue wave on the cn-periodic background, which generalizes the classical rogue wave (the so-called Peregrine’s breather) of the nonlinear Schrödinger equation. We compute the magnification factor for the rogue cn-periodic wave of the mKdV equation and show that it remains constant for all amplitudes. As a by-product of our work, we find explicit expressions for the periodic eigenfunctions of the spectral problem associated with the dn and cn periodic waves of the mKdV equation.

Magnetomechanically induced long period fiber gratings

International Nuclear Information System (INIS)

Causado-Buelvas, Jesus D.; Gomez-Cardona, Nelson D.; Torres, Pedro

2008-01-01

In this work, we report a simple, flexible method to create long period fiber gratings mechanically by controlling the repulsion/attraction force between two magnets that pressing a plate with a periodic array of small glass cylinders to a short length of optical fiber. Via the photoelastic effect, the pressure points induce the required periodic refractive index modulation to create the LPFG. We found that the induced device exhibits spectral characteristics similar to those of other types of LPFG. As the optical properties of LPFGs are directly related to the nature of the applied perturbations, we show, to our knowledge for the frrst time, how is the evolution of birefringence effects in mechanically induced LPFGs

77 FR 27125 - Periodicals-Recognition of Distribution of Periodicals via Electronic Copies

Science.gov (United States)

2012-05-09

... Electronic Copies AGENCY: Postal Service\\TM\\. ACTION: Final rule. SUMMARY: The Postal Service will revise the Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM[supreg]) 707.6 to permit limited reporting of electronic copies of Periodicals publications to satisfy the circulation standards...

Interference pattern period measurement at picometer level

Science.gov (United States)

Xiang, Xiansong; Wei, Chunlong; Jia, Wei; Zhou, Changhe; Li, Minkang; Lu, Yancong

2016-10-01

To produce large scale gratings by Scanning Beam Interference Lithography (SBIL), a light spot containing grating pattern is generated by two beams interfering, and a scanning stage is used to drive the substrate moving under the light spot. In order to locate the stage at the proper exposure positions, the period of the Interference pattern must be measured accurately. We developed a set of process to obtain the period value of two interfering beams at picometer level. The process includes data acquisition and data analysis. The data is received from a photodiode and a laser interferometer with sub-nanometer resolution. Data analysis differs from conventional analyzing methods like counting wave peaks or using Fourier transform to get the signal period, after a preprocess of filtering and envelope removing, the mean square error is calculated between the received signal and ideal sinusoid waves to find the best-fit frequency, thus an accuracy period value is acquired, this method has a low sensitivity to amplitude noise and a high resolution of frequency. With 405nm laser beams interfering, a pattern period value around 562nm is acquired by employing this process, fitting diagram of the result shows the accuracy of the period value reaches picometer level, which is much higher than the results of conventional methods.

Indexing of Popular Periodicals: The State of the Art

Science.gov (United States)

Aveney, Brian; Slade, Rod

1978-01-01

Nine indexing services of popular periodicals are discussed in terms of content, coverage, and characteristics: Access, Consumers Index, Index to Free Periodicals, New York Times Information Bank, Magazine Index, Monthly Periodicals Index, New Periodicals Index, Popular Periodical Index, and Readers Guide. A table indicates coverage for each index…

The periodic table of elementary particles

International Nuclear Information System (INIS)

Bhattacharjee, B.J.

1994-01-01

It is shown that a periodic classification of elementary particles (eps) may be done with the basic properties of eps: viz. mass, spin and parity. Further application of spacing rule and GMO mass formulae show repetitions at very regular intervals. It is found that properties of eps are periodic function of rest mass. (author). 17 refs., 6 tabs

The periodic table of elementary particles

Energy Technology Data Exchange (ETDEWEB)

Bhattacharjee, B J [St. Anthony' s College, Shillong (India). Dept. of Physics

1994-01-01

It is shown that a periodic classification of elementary particles (eps) may be done with the basic properties of eps: viz. mass, spin and parity. Further application of spacing rule and GMO mass formulae show repetitions at very regular intervals. It is found that properties of eps are periodic function of rest mass. (author). 17 refs., 6 tabs.

Online Periodic Table: A Cautionary Note

Science.gov (United States)

Izci, Kemal; Barrow, Lloyd H.; Thornhill, Erica

2013-01-01

The purpose of this study was (a) to evaluate ten online periodic table sources for their accuracy and (b) to compare the types of information and links provided to users. Limited studies have been reported on online periodic table (Diener and Moore 2011; Slocum and Moore in "J Chem Educ" 86(10):1167, 2009). Chemistry students'…

On the Upper Limit (Heaviest Element in the Periodic Table of Elements, and the Periodic Table of Anti-Substance

Directory of Open Access Journals (Sweden)

Khazan A.

2009-04-01

Full Text Available On the basis of the method involving equilateral hyperbolas developed by us with ref- erence to the Periodic Table, its Top Limit has been established. It is the last element with atomic mass 411.66 and serial number 155. The great value, according to our calculation, has adjacent hyperbolas whose center is the point (0; 1. With the method, it has been possible to find just one element in the Periodic Table — Rhodium, which does not demand additional calculations involving the definition of the valid axes. Cal- culations towards updating the charge of a nucleus and the quantity of neutrons in end N-Z part of the diagram by means of the serial number 155 are herein executed. The variant of the Periodic Table of Elements with the eighth period is recommended. On the basis of symmetry, with the application of the Hyperbolic Law in the Periodic Table of Elements, the existence of Anti-Substances is herein indirectly proved.

Periodicity effects on compound waves guided by a thin metal slab sandwiched between two periodically nonhomogeneous dielectric materials

Science.gov (United States)

Chiadini, Francesco; Fiumara, Vincenzo; Scaglione, Antonio; Lakhtakia, Akhlesh

2017-10-01

Surface-plasmon-polariton waves can be compounded when a sufficiently thin metal layer is sandwiched between two half spaces filled with dissimilar periodically nonhomogeneous dielectric materials. We solved the boundary-value problem for compound waves guided by a layer of a homogeneous and isotropic metal sandwiched between a structurally chiral material (SCM) and a periodically multilayered isotropic dielectric (PMLID) material. We found that the periodicities of the PMLID material and the SCM are crucial to excite a multiplicity of compound guided waves arising from strong coupling between the two interfaces.

Periodic optical variability of radio-detected ultracool dwarfs

International Nuclear Information System (INIS)

Harding, L. K.; Golden, A.; Singh, Navtej; Sheehan, B.; Butler, R. F.; Hallinan, G.; Boyle, R. P.; Zavala, R. T.

2013-01-01

A fraction of very low mass stars and brown dwarfs are known to be radio active, in some cases producing periodic pulses. Extensive studies of two such objects have also revealed optical periodic variability, and the nature of this variability remains unclear. Here, we report on multi-epoch optical photometric monitoring of six radio-detected dwarfs, spanning the ∼M8-L3.5 spectral range, conducted to investigate the ubiquity of periodic optical variability in radio-detected ultracool dwarfs. This survey is the most sensitive ground-based study carried out to date in search of periodic optical variability from late-type dwarfs, where we obtained 250 hr of monitoring, delivering photometric precision as low as ∼0.15%. Five of the six targets exhibit clear periodicity, in all cases likely associated with the rotation period of the dwarf, with a marginal detection found for the sixth. Our data points to a likely association between radio and optical periodic variability in late-M/early-L dwarfs, although the underlying physical cause of this correlation remains unclear. In one case, we have multiple epochs of monitoring of the archetype of pulsing radio dwarfs, the M9 TVLM 513–46546, spanning a period of 5 yr, which is sufficiently stable in phase to allow us to establish a period of 1.95958 ± 0.00005 hr. This phase stability may be associated with a large-scale stable magnetic field, further strengthening the correlation between radio activity and periodic optical variability. Finally, we find a tentative spin-orbit alignment of one component of the very low mass binary, LP 349–25.

Periodic optical variability of radio-detected ultracool dwarfs

Energy Technology Data Exchange (ETDEWEB)

Harding, L. K.; Golden, A.; Singh, Navtej; Sheehan, B.; Butler, R. F. [Centre for Astronomy, National University of Ireland, Galway, University Road, Galway (Ireland); Hallinan, G. [Cahill Center for Astrophysics, California Institute of Technology, 1200 East California Boulevard, MC 249-17, Pasadena, CA 91125 (United States); Boyle, R. P. [Vatican Observatory Research Group, Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Zavala, R. T., E-mail: lkh@astro.caltech.edu [United States Naval Observatory, Flagstaff Station, Flagstaff, AZ 86001 (United States)

2013-12-20

A fraction of very low mass stars and brown dwarfs are known to be radio active, in some cases producing periodic pulses. Extensive studies of two such objects have also revealed optical periodic variability, and the nature of this variability remains unclear. Here, we report on multi-epoch optical photometric monitoring of six radio-detected dwarfs, spanning the ∼M8-L3.5 spectral range, conducted to investigate the ubiquity of periodic optical variability in radio-detected ultracool dwarfs. This survey is the most sensitive ground-based study carried out to date in search of periodic optical variability from late-type dwarfs, where we obtained 250 hr of monitoring, delivering photometric precision as low as ∼0.15%. Five of the six targets exhibit clear periodicity, in all cases likely associated with the rotation period of the dwarf, with a marginal detection found for the sixth. Our data points to a likely association between radio and optical periodic variability in late-M/early-L dwarfs, although the underlying physical cause of this correlation remains unclear. In one case, we have multiple epochs of monitoring of the archetype of pulsing radio dwarfs, the M9 TVLM 513–46546, spanning a period of 5 yr, which is sufficiently stable in phase to allow us to establish a period of 1.95958 ± 0.00005 hr. This phase stability may be associated with a large-scale stable magnetic field, further strengthening the correlation between radio activity and periodic optical variability. Finally, we find a tentative spin-orbit alignment of one component of the very low mass binary, LP 349–25.

Integrals of periodic motion and periodic solutions for classical equations of relativistic string with masses at ends. I. Integrals of periodic motion

International Nuclear Information System (INIS)

Barbashov, B.M.

1996-01-01

Boundary equations for the relativistic string with masses at ends are formulated in terms of geometrical invariants of world trajectories of masses at the string ends. In the three-dimensional Minkowski space E 2 1 , there are two invariants of that sort, the curvature K and torsion κ. Curvatures of trajectories of the string ends with masses are always constant, K i =γ/m i (i=1,2), whereas torsions κ i obey a system of differential equations with deviating arguments. For these equations with periodic κ i (τ+nl)=κ(τ), constants of motion are obtained (part 1) and exact solutions are presented (part 2) for periods l and 2l where l is the string length in the plane of parameters τ and σ(σ 1 =0, σ 2 =l). 7 refs

THEORETICAL CEPHEID PERIOD-LUMINOSITY AND PERIOD-COLOR RELATIONS IN SPITZER IRAC BANDS

International Nuclear Information System (INIS)

Ngeow, Chow-Choong; Marconi, Marcella; Musella, Ilaria; Cignoni, Michele; Kanbur, Shashsi M.

2012-01-01

In this paper, the synthetic period-luminosity (P-L) relations in Spitzer's IRAC bands, based on a series of theoretical pulsation models with varying metal and helium abundance, were investigated. Selected sets of these synthetic P-L relations were compared to the empirical IRAC band P-L relations recently determined from Galactic and Magellanic Clouds Cepheids. For the Galactic case, synthetic P-L relations from model sets with (Y = 0.26, Z = 0.01), (Y = 0.26, Z = 0.02), and (Y = 0.28, Z = 0.02) agree with the empirical Galactic P-L relations derived from the Hubble Space Telescope parallaxes. For Magellanic Cloud Cepheids, the synthetic P-L relations from model sets with (Y = 0.25, Z = 0.008) agree with both of the empirical Large Magellanic Cloud (LMC) and Small Magellanic Cloud P-L relations. Analysis of the synthetic P-L relations from all model sets suggested that the IRAC band P-L relations may not be independent of metallicity, as the P-L slopes and intercepts could be affected by the metallicity and/or helium abundance. We also derive the synthetic period-color (P-C) relations in the IRAC bands. Non-vanishing synthetic P-C relations were found for certain combinations of IRAC band filters and metallicity. However, the synthetic P-C relations disagreed with the [3.6]-[8.0] P-C relation recently found for the Galactic Cepheids. The synthetic [3.6]-[4.5] P-C slope from the (Y = 0.25, Z = 0.008) model set, on the other hand, is in excellent agreement to the empirical LMC P-C counterpart, if a period range 1.0 < log (P) < 1.8 is adopted.

The decreasing period of AG Phe

International Nuclear Information System (INIS)

Cerruti, M.A.

1986-01-01

Seven UBV photoelectric times of minimum light are presented. They shift the photographically known period 0 . d 613 to 0 . d 380. The improvement of the light elements leads to a reliable shortening of the period. A rough determination of the mass-ratio permitted to give an estimate of the mass transfer in the system. 13 refs., 1 fig., 1 tab. (author)

Quasi-periodicity in deep redshift surveys

International Nuclear Information System (INIS)

Weygaert, R. van de

1991-01-01

The recent result by Broadhurst et al., (1990. Nature 343, 726) showing a striking, nearly periodic, galaxy redshift distribution in a narrow pencil-beam survey, is explained within the Voronoi cellular model of clustering of galaxies. Galaxies, whose luminosities are selected from a Schechter luminosity function, are placed randomly within the walls of this cellular model. Narrow and deep, magnitude-limited, pencil-beam surveys through these structures are simulated. Some 15 per cent of these beams show that observed regular pattern, with a spacing between the peaks of the order of 105 h -1 -150 h -1 Mpc, but most pencil-beams show peaks in the redshift distribution without periodicity, so we may conclude that, even within a cellular universe, periodicity is not a common phenomenon. (author)

Almost periodic Schroedinger operators

International Nuclear Information System (INIS)

Bellissard, J.; Lima, R.

1984-01-01

These lectures are devoted to recent developments in the theory of almost-periodic Schroedinger Operators. We specially describe the algebraic point of view, with applications to gap-labelling theorems. Particular models are also presented which exhibit various spectral properties. (orig.)

Setting the Periodic Table.

Science.gov (United States)

Saturnelli, Annette

1985-01-01

Examines problems resulting from different forms of the periodic table, indicating that New York State schools use a form reflecting the International Union of Pure and Applied Chemistry's 1984 recommendations. Other formats used and reasons for standardization are discussed. (DH)

Impact of dietary plane of energy during the dry period on lipoprotein parameters in the transition period in dairy cattle.

Science.gov (United States)

Newman, A; Mann, S; Nydam, D V; Overton, T R; Behling-Kelly, E

2016-02-01

The high energy demands of dairy cows during the transition period from late gestation into early lactation can place them at an increased risk for the development of metabolic and infectious diseases. Modification of the dry period diet has been investigated as a preventive means to minimize the detrimental aspects of metabolic shifts during the transition period. Studies investigating the impact of dry period diet on lipid parameters during the transition period have largely focused on markers of lipolysis and ketogenesis. Total cholesterol declines during the periparturient period and increases in early lactation. The impact total energy in the dry period diet has on the ability of the cow to maintain total serum cholesterol, as well as its natural high-density lipoprotein-rich status, during this metabolically challenging window is not clear. The impact of lipoproteins on inflammation and immune function may have a clinical impact on the cow's ability to ward off production-related diseases. In this study, we hypothesized that the provision of adequate, but not excessive, total metabolizable energy, would better allow the cow to maintain total cholesterol and a higher relative proportion of HDL throughout the transition period. Cows were allocated to one of three dry period dietary treatment groups following a randomized block design. Total serum triglycerides, cholesterol and lipoprotein fractions were measured on a weekly basis from approximately 7 weeks pre-calving to 6 weeks post-calving. The cows on the high energy diet maintained total serum cholesterol as compared to the cows provided a lower energy diet, but there was no significant increase in the LDL fraction of lipoproteins between diet treatment groups. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Hydrogen purification by periodic adsorption

Energy Technology Data Exchange (ETDEWEB)

Barg, Christian; Secchi, Argimiro R.; Trierweiler, Jorge O. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Engenharia Quimica]. E-mail: cbarg@enq.ufrgs.br; arge@enq.ufrgs.br; jorge@enq.ufrgs.br

2000-07-01

The periodic adsorption processes have been widely used for industrial applications, mainly because it spends less energy than the usual gas separation processes, like the cryogenic distillation. The largest commercial application of periodic adsorption processes is the pressure swing adsorption (PSA) applied to hydrogen purification. Although its wide use in the chemical and petrochemical industry, there are no reports in the open literature about complete modeling studies of a complex commercial unit, with multiple adsorbents and multiple beds and several feed components. This study has as objective the modeling, optimization and dynamical analysis of an industrial PSA unit for hydrogen purification. (author)

Availability of periodically tested systems

International Nuclear Information System (INIS)

Signoret, J.P.

1979-01-01

There is at the present time a need in accurate models to asess the availability of periodically tested stand-by systems. This paper shows how to improve the well known 'saw-tooth curve' model in order to take into account various reliability parameters. A model is developed to assess the pointwise and the mean availabilities of periodically tested stand-by systems. Exact and approxination formulae are given. In addition, the model developed herein leads to optimize the test interval in order to minimize the mean unavailability. A safety diesel in a nuclear power plant is given as an example

Charged particle periodicity in the Saturnian magnetosphere

International Nuclear Information System (INIS)

Carbary, J.F.; Krimigis, S.M.

1982-01-01

The low energy charged particles (LECP) experiments on the Voyager 1 and 2 spacecraft performed measurements of electrons (approx.22 keV to approx.20 MeV) and ions (approx.28 keV to approx.150 MeV) during the Saturn encounters in 1980 and 1981. Count rate ratios of two of the low energy electron (22 to 35 keV and 183 to 500 keV) and ion (43 to 80 keV and 137 to 215 keV) channels exhibit an approximation 10 hour periodicity in the outer Saturnian magnetosphere beyond the orbit of Titan. Electron ratios vary from approx.50 to approx.300; ion ratios vary from approx.3 to approx.20. Similar but less pronounced periodicities are observed for higher and lower energy electron and ion spectral indices. Three complete cycles were observed during the Voyager 2 outbound portion of the encounter from which were determined an electron ratio period of 10/sup h/21/sup m/ +- 48/sup m/ and an ion ratio period of 9/sup h/49/sup m/ +- 59/sup m/. Using Saturn Kilometric Radiation (SKR) and Saturn Electrostatic Discharge (SED) periods, extrapolation backward from Voyager 2 to Voyager 1 suggests that the periodicities are Saturnian rather than Jovian in nature, and that they persist in phase for time intervals at least as long as 287 days. Ratio minima, or spectral hardenings, occur in the same hemisphere as do auroral brightenings, SKR activity, and spoke enhanement. We interpret the observations as prima facie evidence of an asymmetry in the Saturian magnetic field and the root cause of the observed SKR periodicity

Inferring probabilistic stellar rotation periods using Gaussian processes

Science.gov (United States)

Angus, Ruth; Morton, Timothy; Aigrain, Suzanne; Foreman-Mackey, Daniel; Rajpaul, Vinesh

2018-02-01

Variability in the light curves of spotted, rotating stars is often non-sinusoidal and quasi-periodic - spots move on the stellar surface and have finite lifetimes, causing stellar flux variations to slowly shift in phase. A strictly periodic sinusoid therefore cannot accurately model a rotationally modulated stellar light curve. Physical models of stellar surfaces have many drawbacks preventing effective inference, such as highly degenerate or high-dimensional parameter spaces. In this work, we test an appropriate effective model: a Gaussian Process with a quasi-periodic covariance kernel function. This highly flexible model allows sampling of the posterior probability density function of the periodic parameter, marginalizing over the other kernel hyperparameters using a Markov Chain Monte Carlo approach. To test the effectiveness of this method, we infer rotation periods from 333 simulated stellar light curves, demonstrating that the Gaussian process method produces periods that are more accurate than both a sine-fitting periodogram and an autocorrelation function method. We also demonstrate that it works well on real data, by inferring rotation periods for 275 Kepler stars with previously measured periods. We provide a table of rotation periods for these and many more, altogether 1102 Kepler objects of interest, and their posterior probability density function samples. Because this method delivers posterior probability density functions, it will enable hierarchical studies involving stellar rotation, particularly those involving population modelling, such as inferring stellar ages, obliquities in exoplanet systems, or characterizing star-planet interactions. The code used to implement this method is available online.

Radiation dose rates from adult patients receiving 131I therapy for thyrotoxicosis

International Nuclear Information System (INIS)

O'Doherty, M.J.; Kettle, A.G.; Eustance, C.N.P.; Mountford, P.J.; Coakley, A.J.

1993-01-01

Recommendations for restricting the exposure to radiation of members of the public coming into contact with thyrotoxic patients treated with 131 I are currently based on the activity retained by the patient, and not on the doses likely to be received by such individuals. In order to examine whether these current recommendations restrict these doses to less than the current annual limit of 5 mSv, and to identify the implications of a reduction in this limit to 1 mSv, measurements were made of the dose rates at distances of 0.1, 0.5 and 1.0 m from 60 patients just before they left the nuclear medicine department. These measurements were repeated 1, 3, 6, 8 and 10 days after administration for 30 patients, and the radioactivity in samples of saliva taken on each of these days and secreted in sweat over the first 24 h were also measured. Doses were estimated for administered activities of approximately 200-600 MBq, assuming appropriate values for the times and distances spent near other individuals while travelling, at work, at home and near to young children considered in three age groups. Periods of restriction were derived which would reduce these doses to 5 or 1 mSv. (Author)

Southern hemisphere searches for short period pulsars

International Nuclear Information System (INIS)

Manchester, R.N.

1984-01-01

Two searches of the southern sky for short period pulsars are briefly described. The first, made using the 64-m telescope at Parkes, is sensitive to pulsars with periods greater than about 10 ms and the second, made using the Molonglo radio telescope, has sensitivity down to periods of about 1.5 ms. Four pulsars were found in the Parkes survey and none in the Molonglo survey, although analysis of the latter is as yet incomplete. 10 references, 1 figure, 2 tables

37 CFR 351.2 - Voluntary negotiation period; settlement.

Science.gov (United States)

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Voluntary negotiation period... CONGRESS COPYRIGHT ROYALTY JUDGES RULES AND PROCEDURES PROCEEDINGS § 351.2 Voluntary negotiation period..., the Copyright Royalty Judges will announce the beginning of a voluntary negotiation period and will...

CLINICAL CONCEPTS ON THYROID EMERGENCIES

Directory of Open Access Journals (Sweden)

Alfredo ePontecorvi

2014-07-01

Full Text Available Objective. Thyroid-related emergencies are caused by overt dysfunction of the gland that are so severe that require admission to intensive care units frequently. Nonetheless, in the ICU setting, it is crucial to differentiate patients with non-thyroidal illness and alterations in thyroid function tests from those with intrinsic thyroid disease. This review presents and discusses the main etiopathogenetical and clinical aspects of hypothyroid coma (HC and thyrotoxic storm (TS, including therapeutic strategy flow-charts. Furthermore, a special chapter is dedicated to the approach to massive goiter, which represents a surgical thyroid emergency.Data source. We searched the electronic MEDLINE database to September 2013.Data selection and Data extraction. Reviews, original articles and case reports on myxedematous coma, hypothyroid coma, thyroid storm, thyrotoxic storm, massive goiter, huge goiter, prevalence, etiology, diagnosis, therapy, prognosis were selected.Data synthesis and conclusions. Severe excess or defect of thyroid hormone are rare conditions which jeopardize the life of patients in most cases. Both HC and TS are triggered by precipitating factors, which occur in patients with severe hypothyroidism or thyrotoxicosis, respectively. The pillars of HC therapy are: high dose l-thyroxine and/or tri-iodothyroinine; i.v. glucocorticoids; treatment of hydro-electrolyte imbalance (mainly, hyponatraemia; treatment of hypothermia; not rarely, endotracheal intubation and assisted mechanic ventilation are needed. Therapy of TS is based on beta-blockers, thyrostatics, and i.v. glucocorticoids; eventually, high-dose iodide compounds or lithium carbonate may be of benefit. Surgery represents the gold standard treatment in patients with euthyroid massive nodular goiter, although new techniques – e.g., percutaneous laser ablation - are helpful in subjects at high surgical risk or refusing operation.

Hereditary periodic fever syndromes

NARCIS (Netherlands)

McDermott, MF; Frenkel, J

Hereditary periodic fever syndromes are defined by recurrent attacks of generalised inflammation for which no infectious or auto-immune cause can be identified. For most of these disorders, the molecular basis has recently been elucidated. This has opened the prospect of novel therapeutic

Long-period and short-period variations of ionospheric parameters studied from complex observations performed on Cuba

Energy Technology Data Exchange (ETDEWEB)

Laso, B; Lobachevskii, L A; Potapova, N I; Freizon, I A; Shapiro, B S

1980-09-01

Cuban data from 1978 are used to study long-period (i.e., diurnal) variations of Doppler shift on a 3000 km path at frequencies of 10 and 15 MHz these variations are related to variations of parameters on the ionospheric path. Short-period variations were also studied on the basis of Doppler shift data and vertical sounding data in the 0.000111-0.00113 Hz frequency range. The relation between the observed variations and internal gravity waves are discussed.

Particle separation by external fields on periodic surfaces

International Nuclear Information System (INIS)

Sancho, J M; Khoury, M; Lindenberg, K; Lacasta, A M

2005-01-01

Particles moving on perfect periodic surfaces under the influence of external forces may move along directions that deviate from that of the force. We briefly recall previous results for transport of particles on surfaces with periodic traps or periodic obstacles driven by a constant external force, and present new results for particles moving in a harmonic periodic potential. The sorting properties are explored as a function of a number of control parameters, specifically the friction, force amplitude and direction, temperature, and lattice constants

40 CFR 45.140 - Budget and project period.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Budget and project period. 45.140 Section 45.140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE TRAINING ASSISTANCE § 45.140 Budget and project period. The budget and project periods for...

Optimal glucose management in the perioperative period.

Science.gov (United States)

Evans, Charity H; Lee, Jane; Ruhlman, Melissa K

2015-04-01

Hyperglycemia is a common finding in surgical patients during the perioperative period. Factors contributing to poor glycemic control include counterregulatory hormones, hepatic insulin resistance, decreased insulin-stimulated glucose uptake, use of dextrose-containing intravenous fluids, and enteral and parenteral nutrition. Hyperglycemia in the perioperative period is associated with increased morbidity, decreased survival, and increased resource utilization. Optimal glucose management in the perioperative period contributes to reduced morbidity and mortality. To readily identify hyperglycemia, blood glucose monitoring should be instituted for all hospitalized patients. Published by Elsevier Inc.

Exploring fMRI Data for Periodic Signal Components

DEFF Research Database (Denmark)

Hansen, Lars Kai; Nielsen, Finn Årup; Larsen, Jan

2002-01-01

We use a Bayesian framework to detect periodic components in fMRI data. The resulting detector is sensitive to periodic components with a flexible number of harmonics and with arbitrary amplitude and phases of the harmonics. It is possible to detect the correct number of harmonics in periodic sig...

THEORETICAL CEPHEID PERIOD-LUMINOSITY AND PERIOD-COLOR RELATIONS IN SPITZER IRAC BANDS

Energy Technology Data Exchange (ETDEWEB)

Ngeow, Chow-Choong [Graduate Institute of Astronomy, National Central University, Jhongli City 32001, Taiwan (China); Marconi, Marcella; Musella, Ilaria [Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli (Italy); Cignoni, Michele [Department of Astronomy, Bologna University, via Ranzani 1, 40127 Bologna (Italy); Kanbur, Shashsi M. [Department of Physics, State University of New York at Oswego, Oswego, NY 13126 (United States)

2012-02-01

In this paper, the synthetic period-luminosity (P-L) relations in Spitzer's IRAC bands, based on a series of theoretical pulsation models with varying metal and helium abundance, were investigated. Selected sets of these synthetic P-L relations were compared to the empirical IRAC band P-L relations recently determined from Galactic and Magellanic Clouds Cepheids. For the Galactic case, synthetic P-L relations from model sets with (Y = 0.26, Z = 0.01), (Y = 0.26, Z = 0.02), and (Y = 0.28, Z = 0.02) agree with the empirical Galactic P-L relations derived from the Hubble Space Telescope parallaxes. For Magellanic Cloud Cepheids, the synthetic P-L relations from model sets with (Y = 0.25, Z = 0.008) agree with both of the empirical Large Magellanic Cloud (LMC) and Small Magellanic Cloud P-L relations. Analysis of the synthetic P-L relations from all model sets suggested that the IRAC band P-L relations may not be independent of metallicity, as the P-L slopes and intercepts could be affected by the metallicity and/or helium abundance. We also derive the synthetic period-color (P-C) relations in the IRAC bands. Non-vanishing synthetic P-C relations were found for certain combinations of IRAC band filters and metallicity. However, the synthetic P-C relations disagreed with the [3.6]-[8.0] P-C relation recently found for the Galactic Cepheids. The synthetic [3.6]-[4.5] P-C slope from the (Y = 0.25, Z = 0.008) model set, on the other hand, is in excellent agreement to the empirical LMC P-C counterpart, if a period range 1.0 < log (P) < 1.8 is adopted.

Medicine in Balkans during the Roman Period.

Science.gov (United States)

Baykan, Daniş

2017-08-04

The aim of this study is to investigate the archaeological finds to enlighten the medical methods of treatments and operations applied in Balkans during Roman Period. Some independent local and regional find groups, taken from existing publications will be grouped together and a holistic point-of-view will be taken against medicine in Balkan Geography during Roman Period. Due to basic differences it contained, the data before Roman Period are excluded. Most of Greece and Aegean Islands are also excluded since the topic selected is "Medicine of Roman Period." Greece and Aegean Islands should be evaluated in another study in connection with West Anatolia which is closer than the Balkan Geography in terms of social relations. The spread of medical tools in Balkans during Roman Period is concentrated around military garrisons, and in settlements built around military pathways, and in settlements containing an amphitheater associated with gladiators. This spread is verified by the studies on Bulgaria in general. The data is also compatible with the assertion suggesting that the amount of application of pharmaceutical treatment increases when one moves away from the military centres.

An improved test for periodicity

International Nuclear Information System (INIS)

Davies, S.R.

1990-01-01

I discuss two widely used methods of testing for periodicity, phase dispersion minimization and epoch-folding. Using an analysis of variance approach, I demonstrate the close relationship between these two methods. I also show that the significance test sometimes used in phase dispersion minimization is statistically inaccurate, and that the test used in epoch-folding is an approximation valid only for large sample sizes. I propose a new test statistic, applicable to either epoch-folding or PDM, which is statistically sound for all sample sizes, and which is also more sensitive to periodicity than the test statistics previously used with these two methods. (author)

Sensitivity analysis of periodic errors in heterodyne interferometry

International Nuclear Information System (INIS)

Ganguly, Vasishta; Kim, Nam Ho; Kim, Hyo Soo; Schmitz, Tony

2011-01-01

Periodic errors in heterodyne displacement measuring interferometry occur due to frequency mixing in the interferometer. These nonlinearities are typically characterized as first- and second-order periodic errors which cause a cyclical (non-cumulative) variation in the reported displacement about the true value. This study implements an existing analytical periodic error model in order to identify sensitivities of the first- and second-order periodic errors to the input parameters, including rotational misalignments of the polarizing beam splitter and mixing polarizer, non-orthogonality of the two laser frequencies, ellipticity in the polarizations of the two laser beams, and different transmission coefficients in the polarizing beam splitter. A local sensitivity analysis is first conducted to examine the sensitivities of the periodic errors with respect to each input parameter about the nominal input values. Next, a variance-based approach is used to study the global sensitivities of the periodic errors by calculating the Sobol' sensitivity indices using Monte Carlo simulation. The effect of variation in the input uncertainty on the computed sensitivity indices is examined. It is seen that the first-order periodic error is highly sensitive to non-orthogonality of the two linearly polarized laser frequencies, while the second-order error is most sensitive to the rotational misalignment between the laser beams and the polarizing beam splitter. A particle swarm optimization technique is finally used to predict the possible setup imperfections based on experimentally generated values for periodic errors

Sensitivity analysis of periodic errors in heterodyne interferometry

Science.gov (United States)

Ganguly, Vasishta; Kim, Nam Ho; Kim, Hyo Soo; Schmitz, Tony

2011-03-01

Periodic errors in heterodyne displacement measuring interferometry occur due to frequency mixing in the interferometer. These nonlinearities are typically characterized as first- and second-order periodic errors which cause a cyclical (non-cumulative) variation in the reported displacement about the true value. This study implements an existing analytical periodic error model in order to identify sensitivities of the first- and second-order periodic errors to the input parameters, including rotational misalignments of the polarizing beam splitter and mixing polarizer, non-orthogonality of the two laser frequencies, ellipticity in the polarizations of the two laser beams, and different transmission coefficients in the polarizing beam splitter. A local sensitivity analysis is first conducted to examine the sensitivities of the periodic errors with respect to each input parameter about the nominal input values. Next, a variance-based approach is used to study the global sensitivities of the periodic errors by calculating the Sobol' sensitivity indices using Monte Carlo simulation. The effect of variation in the input uncertainty on the computed sensitivity indices is examined. It is seen that the first-order periodic error is highly sensitive to non-orthogonality of the two linearly polarized laser frequencies, while the second-order error is most sensitive to the rotational misalignment between the laser beams and the polarizing beam splitter. A particle swarm optimization technique is finally used to predict the possible setup imperfections based on experimentally generated values for periodic errors.

IUPAC Periodic Table of the Isotopes

Science.gov (United States)

Holden, N.E.; Coplen, T.B.; Böhlke, J.K.; Wieser, M.E.; Singleton, G.; Walczyk, T.; Yoneda, S.; Mahaffy, P.G.; Tarbox, L.V.

2011-01-01

For almost 150 years, the Periodic Table of the Elements has served as a guide to the world of elements by highlighting similarities and differences in atomic structure and chemical properties. To introduce students, teachers, and society to the existence and importance of isotopes of the chemical elements, an IUPAC Periodic Table of the Isotopes (IPTI) has been prepared and can be found as a supplement to this issue.

Periodicity and Immortality in Reversible Computing

OpenAIRE

Kari , Jarkko; Ollinger , Nicolas

2008-01-01

Additional material available on the web at http://www.lif.univ-mrs.fr/~nollinge/rec/gnirut/; We investigate the decidability of the periodicity and the immortality problems in three models of reversible computation: reversible counter machines, reversible Turing machines and reversible one-dimensional cellular automata. Immortality and periodicity are properties that describe the behavior of the model starting from arbitrary initial configurations: immortality is the property of having at le...

New serial time codes for seismic short period and long period data acquisition systems

International Nuclear Information System (INIS)

Kolvankar, V.G.; Rao, D.S.

1988-01-01

This paper discusses a new time code for time indexing multichannel short period (1 to 25 hz) seismic event data recorded on a single track of magnetic tape in digital format and discusses its usefulness in contrast to Vela time code used in continuous analog multichannel data recording system on multitrack instrumentation tape deck. This paper also discusses another time code, used for time indexing of seismic long period (DC to 2.5 seconds) multichannel data recorded on a single track of magnetic tape in digital format. The time code decoding and display system developed to provide quick access to any desired portion of the tape in both data recording and repro duce system is also discussed. (author). 7 figs

Attractors of the periodically forced Rayleigh system

Directory of Open Access Journals (Sweden)

Petre Bazavan

2011-07-01

Full Text Available The autonomous second order nonlinear ordinary differential equation(ODE introduced in 1883 by Lord Rayleigh, is the equation whichappears to be the closest to the ODE of the harmonic oscillator withdumping.In this paper we present a numerical study of the periodic andchaotic attractors in the dynamical system associated with the generalized Rayleigh equation. Transition between periodic and quasiperiodic motion is also studied. Numerical results describe the system dynamics changes (in particular bifurcations, when the forcing frequency is varied and thus, periodic, quasiperiodic or chaotic behaviour regions are predicted.

Prediction of Vibration Transmission within Periodic Bar Structures

DEFF Research Database (Denmark)

Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard; Sorokin, Sergey

2012-01-01

The present analysis focuses on vibration transmission within semi-infinite bar structure. The bar is consisting of two different materials in a periodic manner. A periodic bar model is generated using two various methods: The Finite Element method (FEM) and a Floquet theory approach. A parameter...... study is carried out regarding the influence of the number of periods at various frequencies within a semi-infinite bar, stop bands are illustrated at certain periodic intervals within the structure. The computations are carried out in frequency domain in the range below 500 Hz. Results from both...

Periods for Calabi-Yau and Landau-Ginzburg vacua

CERN Document Server

Berglund, P; De la Ossa, X C; Font, A; Hübsch, T; Jancic, D; Quevedo, Fernando; Berglund, Per; Candelas, Philip; Ossa, Xenia de la; Font, Anamaria; Hubsch, Tristan; Jancic, Dubravka; Quevedo, Fernando

1994-01-01

The complete structure of the moduli space of \\cys\\ and the associated Landau-Ginzburg theories, and hence also of the corresponding low-energy effective theory that results from (2,2) superstring compactification, may be determined in terms of certain holomorphic functions called periods. These periods are shown to be readily calculable for a great many such models. We illustrate this by computing the periods explicitly for a number of classes of \\cys. We also point out that it is possible to read off from the periods certain important information relating to the mirror manifolds.

A Modern Periodic Table.

Science.gov (United States)

Herrenden-Harker, B. D.

1997-01-01

Presents a modern Periodic Table based on the electron distribution in the outermost shell and the order of filling of the sublevels within the shells. Enables a student to read off directly the electronic configuration of the element and the order in which filling occurs. (JRH)

[Hyperthyroidism in molar pregnancy].

Science.gov (United States)

Boufettal, H; Mahdoui, S; Noun, M; Hermas, S; Samouh, N

2014-03-01

Hyperthyroidism is a rare complication of molar pregnancy. We report a 39-year-old woman who presented a thyrotoxic syndrome accompanying a molar pregnancy. Serum thyroid hormones were elevated and returned to normal level after uterine evacuation of a molar pregnancy. The authors detail the role of thyroid stimulating property of human gonadotropin chorionic hormone and its structural changes during the gestational trophoblastic diseases. These changes give the latter the thyroid stimulating properties and signs of hyperthyroidism. Molar pregnancy may be a cause of hyperthyroidism. The diagnosis of molar pregnancy should be a mention to thyrotoxicosique syndrome in a woman of childbearing age. Copyright © 2013. Published by Elsevier SAS.

Critical Period of Weed Control in Aerobic Rice

Science.gov (United States)

Anwar, M. P.; Juraimi, A. S.; Samedani, B.; Puteh, A.; Man, A.

2012-01-01

Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. Critical period was determined through Logistic and Gompertz equations. Critical period varied between seasons; in main season, it started earlier and lasted longer, as compared to off-season. The onset of the critical period was found relatively stable between seasons, while the end was more variable. Critical period was determined as 7–49 days after seeding in off-season and 7–53 days in main season to achieve 95% of weed-free yield, and 23–40 days in off-season and 21–43 days in main season to achieve 90% of weed-free yield. Since 5% yield loss level is not practical from economic view point, a 10% yield loss may be considered excellent from economic view point. Therefore, aerobic rice should be kept weed-free during 21–43 days for better yield and higher economic return. PMID:22778701

Policy Uncertainty, Investment and Commitment Periods

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

Today's investment decisions in key sectors such as energy, forestry or transport have significant impacts on the levels of greenhouse gas (GHG) emissions over the coming decades. Given the economic and environmental long-term implications of capital investment and retirement, a climate mitigation regime should aim to encourage capital investment in climate-friendly technologies. Many factors affect technology choice and the timing of investment, including investor expectations about future prices and policies. Recent international discussions have focused on the importance of providing more certainty about future climate policy stringency. The design of commitment periods can play a role in creating this environment. This paper assesses how the length of commitment periods influences policy uncertainty and investment decisions. In particular, the paper analyses the relationship between commitment period length and near term investment decisions in climate friendly technology.

Krsko NPP Periodic Safety Review program

International Nuclear Information System (INIS)

Basic, I.; Spiler, J.; Novsak, M.

2001-01-01

The need for conducting a Periodic Safety Review for the Krsko NPP has been clearly recognized both by the NEK and the regulator (SNSA). The PSR would be highly desirable both in the light of current trends in safety oversight practices and because of many benefits it is capable to provide. On January 11, 2001 the SNSA issued a decision requesting the Krsko NPP to prepare a program and determine a schedule for the implementation of the program for 'Periodic Safety Review of NPP Krsko'. The program, which is required to be in accordance with the IAEA safety philosophy and with the EU practice, was submitted for the approval to the SNSA by the end of March 2001. The paper summarizes Krsko NPP Periodic Safety Review Program [1] including implemented SNSA and IAEA Expert Mission comments.(author)

Development of Seismic Isolation Systems Using Periodic Materials

Energy Technology Data Exchange (ETDEWEB)

Yan, Yiqun [Univ. of Houston, Houston, TX (United States); Mo, Yi-Lung [Univ. of Houston, Houston, TX (United States); Menq, Farn-Yuh [Univ. of Texas, Austin, TX (United States); Stokoe, II, Kenneth H. [Univ. of Texas, Austin, TX (United States); Perkins, Judy [Prairie View A & M University, Prairie View, TX (United States); Tang, Yu [Argonne National Lab. (ANL), Argonne, IL (United States)

2014-12-10

Advanced fast nuclear power plants and small modular fast reactors are composed of thin-walled structures such as pipes; as a result, they do not have sufficient inherent strength to resist seismic loads. Seismic isolation, therefore, is an effective solution for mitigating earthquake hazards for these types of structures. Base isolation, on which numerous studies have been conducted, is a well-defined structure protection system against earthquakes. In conventional isolators, such as high-damping rubber bearings, lead-rubber bearings, and friction pendulum bearings, large relative displacements occur between upper structures and foundations. Only isolation in a horizontal direction is provided; these features are not desirable for the piping systems. The concept of periodic materials, based on the theory of solid-state physics, can be applied to earthquake engineering. The periodic material is a material that possesses distinct characteristics that prevent waves with certain frequencies from being transmitted through it; therefore, this material can be used in structural foundations to block unwanted seismic waves with certain frequencies. The frequency band of periodic material that can filter out waves is called the band gap, and the structural foundation made of periodic material is referred to as the periodic foundation. The design of a nuclear power plant, therefore, can be unified around the desirable feature of a periodic foundation, while the continuous maintenance of the structure is not needed. In this research project, three different types of periodic foundations were studied: one-dimensional, two-dimensional, and three-dimensional. The basic theories of periodic foundations are introduced first to find the band gaps; then the finite element methods are used, to perform parametric analysis, and obtain attenuation zones; finally, experimental programs are conducted, and the test data are analyzed to verify the theory. This procedure shows that the

A Novel Hypokalemic-Alkalotic Salt-Losing Tubulopathy in Patients with CLDN10 Mutations.

NARCIS (Netherlands)

Bongers, E.M.H.F.; Shelton, L.M.; Milatz, S.; Verkaart, S.A.; Bech, A.P.; Schoots, J.; Cornelissen, E.A.M.; Bleich, M.; Hoenderop, J.G.J.; Wetzels, J.F.M.; Lugtenberg, D.; Nijenhuis, T.

2017-01-01

Mice lacking distal tubular expression of CLDN10, the gene encoding the tight junction protein Claudin-10, show enhanced paracellular magnesium and calcium permeability and reduced sodium permeability in the thick ascending limb (TAL), leading to a urine concentrating defect. However, the function

Nephropathic Cystinosis Mimicking Bartter Syndrome: a Novel Mutation.

Science.gov (United States)

Bastug, Funda; Nalcacioglu, Hulya; Ozaltin, Fatih; Korkmaz, Emine; Yel, Sibel

2018-01-01

Cystinosis is a rare autosomal recessive disorder resulting from defective lysosomal transport of cystine due to mutations in the cystinosin lysosomal cystine transporter (CTNS) gene. The clinical phenotype of nephropathic cystinosis is characterized by renal tubular Fanconi syndrome and development of end-stage renal disease during the first decade. Although metabolic acidosis is the classically prominent finding of the disease, a few cases may present with hypokalemic metabolic alkalosis mimicking Bartter syndrome. Bartter-like presentation may lead to delay in diagnosis and initiation of specific treatment for cystinosis. We report a case of a 6-year-old girl initially presenting with the features of Bartter syndrome that was diagnosed 2 years later with nephropathic cystinosis and a novel CTNS mutation.

Inherited renal tubular defects with hypokalemia

Directory of Open Access Journals (Sweden)

Muthukrishnan J

2009-01-01

Full Text Available Bartter′s and Gitelman′s syndrome are two ends of a spectrum of inherited renal tubular disorders that present with hypokalemic metabolic alkalosis of varying severity. Clinical features and associated calcium and magnesium ion abnormalities are used to diagnose these cases after excluding other commoner causes. We report on two cases, the first being a young boy, born of pregnancy complicated by polyhydramnios, who had classical dysmorphic features, polyuria, hypokalemia and hypercalciuria and was diagnosed as having Bartter′s syndrome. The second patient is a lady who had recurrent tetany as the only manifestation of Gitelman′s syndrome, which is an unusual presentation. Potassium replacement with supplementation of other deficient ions led to satisfactory clinical and biochemical response.

Some Reflections on the Periodic Table and Its Use.

Science.gov (United States)

Fernelius, W. Conard

1986-01-01

Discusses early periodic tables; effect on the periodic table of atomic numbers; the periodic table in relation to electron distribution in the atoms of elements; terms and concepts related to the table; and the modern basis of the periodic table. Additional comments about these and other topics are included. (JN)

Biomimetic Wind Turbine Design with Lift Enhancing Periodic Stall

NARCIS (Netherlands)

Stamhuis, Eize Jan

2017-01-01

A wind turbine includes a rotor; a blade; and a periodic stall system. The periodic stall system selectively moves at least part of the blade in an oscillating motion whereby an angle of incidence continuously varies to invoke periodic stall. The periodic stall system can move the entire blade or

Entanglement of periodic anisotropic XY chains

International Nuclear Information System (INIS)

Zhang Lifa; Tong Peiqing

2005-01-01

By using the concept of concurrence, the entanglement of periodic anisotropic XY chains in a transverse field is studied numerically. It is found that the derivatives ∂ λ C(1) of nearest-neighbour concurrence diverge at quantum critical points. By proper scaling, we found that all the derivatives ∂ λ C(1) for periodic XY chains in the vicinity of quantum critical points have the same behaviours as that of a uniform chain

Periodic oscillation of higher-order bidirectional associative memory neural networks with periodic coefficients and delays

Science.gov (United States)

Ren, Fengli; Cao, Jinde

2007-03-01

In this paper, several sufficient conditions are obtained ensuring existence, global attractivity and global asymptotic stability of the periodic solution for the higher-order bidirectional associative memory neural networks with periodic coefficients and delays by using the continuation theorem of Mawhin's coincidence degree theory, the Lyapunov functional and the non-singular M-matrix. Two examples are exploited to illustrate the effectiveness of the proposed criteria. These results are more effective than the ones in the literature for some neural networks, and can be applied to the design of globally attractive or globally asymptotically stable networks and thus have important significance in both theory and applications.

Impact of the infectious period on epidemics

Science.gov (United States)

Wilkinson, Robert R.; Sharkey, Kieran J.

2018-05-01

The duration of the infectious period is a crucial determinant of the ability of an infectious disease to spread. We consider an epidemic model that is network based and non-Markovian, containing classic Kermack-McKendrick, pairwise, message passing, and spatial models as special cases. For this model, we prove a monotonic relationship between the variability of the infectious period (with fixed mean) and the probability that the infection will reach any given subset of the population by any given time. For certain families of distributions, this result implies that epidemic severity is decreasing with respect to the variance of the infectious period. The striking importance of this relationship is demonstrated numerically. We then prove, with a fixed basic reproductive ratio (R0), a monotonic relationship between the variability of the posterior transmission probability (which is a function of the infectious period) and the probability that the infection will reach any given subset of the population by any given time. Thus again, even when R0 is fixed, variability of the infectious period tends to dampen the epidemic. Numerical results illustrate this but indicate the relationship is weaker. We then show how our results apply to message passing, pairwise, and Kermack-McKendrick epidemic models, even when they are not exactly consistent with the stochastic dynamics. For Poissonian contact processes, and arbitrarily distributed infectious periods, we demonstrate how systems of delay differential equations and ordinary differential equations can provide upper and lower bounds, respectively, for the probability that any given individual has been infected by any given time.

Periodic vehicle inspection (MOT). [previously: Periodic Vehicle Inspection of cars (MOT).

OpenAIRE

2010-01-01

In the 1980s the periodic vehicle inspection (MOT) of various categories of vehicles was introduced in the Netherlands. This fact sheet will discuss the legal framework of this measure and the research carried out into its effects on road safety, also in an international context. For instance, the technical conditions of cars at inspection as well as that of cars involved in crashes were studied. Tyre pressure will also be discussed in this fact sheet.

7 CFR 1.603 - How are time periods computed?

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false How are time periods computed? 1.603 Section 1.603... Licenses General Provisions § 1.603 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2...

How Do Earth-Sized, Short-Period Planets Form?

Science.gov (United States)

Kohler, Susanna

2017-08-01

Matching theory to observation often requires creative detective work. In a new study, scientists have used a clever test to reveal clues about the birth of speedy, Earth-sized planets.Former Hot Jupiters?Artists impression of a hot Jupiter with an evaporating atmosphere. [NASA/Ames/JPL-Caltech]Among the many different types of exoplanets weve observed, one unusual category is that of ultra-short-period planets. These roughly Earth-sized planets speed around their host stars at incredible rates, with periods of less than a day.How do planets in this odd category form? One popular theory is that they were previously hot Jupiters, especially massive gas giants orbiting very close to their host stars. The close orbit caused the planets atmospheres to be stripped away, leaving behind only their dense cores.In a new study, a team of astronomers led by Joshua Winn (Princeton University) has found a clever way to test this theory.Planetary radius vs. orbital period for the authors three statistical samples (colored markers) and the broader sample of stars in the California Kepler Survey. [Winn et al. 2017]Testing MetallicitiesStars hosting hot Jupiters have an interesting quirk: they typically have metallicities that are significantly higher than an average planet-hosting star. It is speculated that this is because planets are born from the same materials as their host stars, and hot Jupiters require the presence of more metals to be able to form.Regardless of the cause of this trend, if ultra-short-period planets are in fact the solid cores of former hot Jupiters, then the two categories of planets should have hosts with the same metallicity distributions. The ultra-short-period-planet hosts should therefore also be weighted to higher metallicities than average planet-hosting stars.To test this, the authors make spectroscopic measurements and gather data for a sample of stellar hosts split into three categories:64 ultra-short-period planets (orbital period shorter than a

Can oscillating physics explain an apparently periodic universe?

International Nuclear Information System (INIS)

Hill, C.T.; Steinhardt, P.J.; Turner, M.S.; Chicago Univ., IL; Fermi National Accelerator Lab., Batavia, IL

1990-01-01

Recently, Broadhurst et al. have reported an apparent periodicity in a north-south pencil-beam red-shift survey of galaxies. We consider whether the periodicity may be an illusion caused by the oscillations of physical constants. Should the periodicity be disproven by subsequent observations, the same analysis can be used to derive new, stringent limits on the variations of physical constants. (orig.)

[Hypertension and pregnancy: Post-partum period].

Science.gov (United States)

Hugon-Rodin, Justine; Plu-Bureau, Geneviève

2016-01-01

Post-partum period is associated with specific characteristics in women with gestational disorders or preeclampsia. For breastfeeding women, the choice of antihypertensive treatment should take into account the impact on child health. The impact of breastfeeding on health mother must be also discussed. Moreover, for lactation inhibition, bromocriptine should not be used, especially in the context of gestational disorders. In post-partum period, the best contraceptive strategy is only-progestin contraception or non-hormonal contraceptives use. However, this choice will depend on the stabilization or normalization of blood pressure in early post-partum period. Finally, several consultations should be suggested: an information and announcement to explain the consequences of these gestational disorders and organize their multidisciplinary management and follow-up. A preconceptional consultation takes its place to anticipate potential recurrent preeclampsia or gestational hypertension and to schedule a future pregnancy in optimal conditions. Copyright © 2016. Published by Elsevier Masson SAS.

Vlasov dynamics of periodically driven systems

Science.gov (United States)

Banerjee, Soumyadip; Shah, Kushal

2018-04-01

Analytical solutions of the Vlasov equation for periodically driven systems are of importance in several areas of plasma physics and dynamical systems and are usually approximated using ponderomotive theory. In this paper, we derive the plasma distribution function predicted by ponderomotive theory using Hamiltonian averaging theory and compare it with solutions obtained by the method of characteristics. Our results show that though ponderomotive theory is relatively much easier to use, its predictions are very restrictive and are likely to be very different from the actual distribution function of the system. We also analyse all possible initial conditions which lead to periodic solutions of the Vlasov equation for periodically driven systems and conjecture that the irreducible polynomial corresponding to the initial condition must only have squares of the spatial and momentum coordinate. The resulting distribution function for other initial conditions is aperiodic and can lead to complex relaxation processes within the plasma.

Periodic solutions of Volterra integral equations

Directory of Open Access Journals (Sweden)

M. N. Islam

1988-01-01

Full Text Available Consider the system of equationsx(t=f(t+∫−∞tk(t,sx(sds,           (1andx(t=f(t+∫−∞tk(t,sg(s,x(sds.       (2Existence of continuous periodic solutions of (1 is shown using the resolvent function of the kernel k. Some important properties of the resolvent function including its uniqueness are obtained in the process. In obtaining periodic solutions of (1 it is necessary that the resolvent of k is integrable in some sense. For a scalar convolution kernel k some explicit conditions are derived to determine whether or not the resolvent of k is integrable. Finally, the existence and uniqueness of continuous periodic solutions of (1 and (2 are btained using the contraction mapping principle as the basic tool.

About periodic and quasi-periodic orbits of a new type for twist maps of the torus

Directory of Open Access Journals (Sweden)

SALVADOR ADDAS-ZANATA

2002-03-01

Full Text Available We prove that for a large and important class of C¹ twist maps of the torus periodic and quasi-periodic orbits of a new type exist, provided that there are no rotational invariant circles (R.I.C's. These orbits have a non-zero "vertical rotation number'' (V.R.N., in contrast to what happens to Birkhoff periodic orbits and Aubry-Mather sets. The V.R.N. is rational for a periodic orbit and irrational for a quasi-periodic. We also prove that the existence of an orbit with a V.R.N = a > 0, implies the existence of orbits with V.R.N = b, for all 0 Provamos que para uma relevante classe de aplicações C¹ no toro, que desviam a vertical para a direita, existem órbitas periódicas e quase-periódicas de um novo tipo, se e somente se, não existem círculos rotacionais invariantes. Essas órbitas têm um número de rotação vertical não nulo (N.R.V, em contraste com o que ocorre para órbitas periódicas do tipo Birkhoff e para os conjuntos de Aubry-Mather. O número de rotação vertical é racional para uma órbita periódica e irracional para uma quase-periódica. Também provamos que a existência de uma órbita com N.R.V = a implica a existência de órbitas com N.R.V = b, para todo 0 < b < a. Como consequência destes resultados, obtemos que uma aplicação do toro que desvia a vertical e não possui círculos rotacionais invariates, necessariamente tem entropia topológica positiva, que é um resultado clássico. No fim deste trabalho apresentamos aplicações e exemplos, como o Standard map, dos resultados obtidos.

de pauta periodística

Directory of Open Access Journals (Sweden)

Soledad Puente

2014-01-01

Full Text Available En Chile, la rutina periodística suele responder a un proceso basado princi- palmente en la intuición, entendida como aquella reacción sobre la marcha frente a eventos de la contingencia con relevancia social. Los editores, que están a cargo de este proceso, sin importar el tipo de medio de información social en que trabajen, toman las decisiones principalmente de acuerdo con su experiencia y olfato periodístico, lo que incide directamente en la calidad de los contenidos y en su coherencia con la línea editorial del medio. Mien- tras, por un lado, la llegada de las nuevas tecnologías ha modificado el acce- so a la información de los ciudadanos, por otro, ha complejizado el trabajo en la sala de noticias, independientemente de su soporte. La noticia hoy es un commodity, lo que reduce las posibilidades de golpe periodístico y exi- ge mayores elementos de novedad. La figura del editor o gatekeeper es hoy más importante que nunca, porque es el encargado de seleccionar y jerar- quizar cuáles serán las unidades noticiosas más relevantes para la toma de decisiones de los ciudadanos. A través de entrevistas en profundidad a di- rectores, editores y periodistas de medios de referencia chilenos de diarios, televisión, agencias de noticias y nuevos medios, el equipo que presenta este trabajo revisó y sistematizó los momentos críticos del proceso de toma de decisiones periodísticas. Con esa información, diseñó un proceso genéri- co denominado, según la literatura, ‘diagrama de flujo para la modelación de procesos de negocios’, al que posteriormente se aplicó la metodología SIPOC para determinar el alcance del proceso y la matriz RECI para defi- nir actividades y roles de quienes participan en ellas. Se establecieron así las etapas imprescindibles del trabajo periodístico: proposición, decisión y seguimiento de la ejecución de la unidad noticiosa. Al finalizar el mode- lamiento, se llevó a cabo su validación por parte

Electric fuses operation, a review: 2. Arcing period

International Nuclear Information System (INIS)

Bussière, W

2012-01-01

In the electric fuse operation the arcing period follows immediately the pre-arcing period depicted in Part 1 (Part 1. Pre-arcing period). The transition between these two operation steps is not fully understood at this time. To simplify the beginning of the arcing period can be identified with the electric arc ignition i.e. with the electrodes voltage drop. The consecutive plasma is of metallic type at the beginning of the arcing period and of metallic plus silica type with varying mixture up to the end of the arcing period. The energy brought by the fault current is withdrawn by means of the interaction between the electric arc and the arc quenching material (usually silica sand) whose morphometric properties influence the properties of the plasma column: composition, thermodynamic properties and transport coefficients of the plasma column depend on the porosity (and other morphometric properties) of the filler. The fuse element erosion also known as burn-back is responsible for the lengthening of the plasma column and the variations of the electric field. The whole of these processes is depicted by means of experimental results or modellings when possible.

Transverse impedance of a periodic array of cavities

Directory of Open Access Journals (Sweden)

A. V. Fedotov

1999-06-01

Full Text Available We examine the transverse impedance of a periodic array of cavities in a beam pipe at high frequency. The calculation is an extension of a previous one for the longitudinal impedance of a periodic array of azimuthally symmetric pillboxes, for which only TM modes were needed. In the present case, we must include TE modes as well. In addition, we extend the applicability of the previous calculation by including an extra term in the coupling kernel so that the results are valid for all values of the ratio of the cavity length to the period of the structure (all values of the ratio of iris thickness to structure period. In spite of the presence of TE modes, we find that the high frequency limit of the transverse impedance is simply (2/ka^{2} times the corresponding limit of the longitudinal impedance, just as it is for the resistive wall impedances, a relation which occurs frequently for azimuthally symmetric structures. Finally, we present numerical results as well as approximate expressions for the impedance per period, valid for all ratios of cavity length to structure period.

Periodic Table of Students.

Science.gov (United States)

Johnson, Mike

1998-01-01

Presents an exercise in which an eighth-grade science teacher decorated the classroom with a periodic table of students. Student photographs were arranged according to similarities into vertical columns. Students were each assigned an atomic number according to their placement in the table. The table is then used to teach students about…

50 CFR 221.3 - How are time periods computed?

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false How are time periods computed? 221.3... Provisions § 221.3 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2) The last day of the...

Resonances in a periodically driven bosonic system

NARCIS (Netherlands)

Quelle, Anton; de Morais Smith, Cristiane

2017-01-01

Periodically driven systems are a common topic in modern physics. In optical lattices specifically, driving is at the origin of many interesting phenomena. However, energy is not conserved in driven systems, and under periodic driving, heating of a system is a real concern. In an effort to better

Global attractivity of positive periodic solution to periodic Lotka-Volterra competition systems with pure delay

Science.gov (United States)

Tang, Xianhua; Cao, Daomin; Zou, Xingfu

We consider a periodic Lotka-Volterra competition system without instantaneous negative feedbacks (i.e., pure-delay systems) x(t)=x(t)[r(t)-∑j=1na(t)x(t-τ(t))], i=1,2,…,n. We establish some 3/2-type criteria for global attractivity of a positive periodic solution of the system, which generalize the well-known Wright's 3/2 criteria for the autonomous delay logistic equation, and thereby, address the open problem proposed by both Kuang [Y. Kuang, Global stability in delayed nonautonomous Lotka-Volterra type systems without saturated equilibria, Differential Integral Equations 9 (1996) 557-567] and Teng [Z. Teng, Nonautonomous Lotka-Volterra systems with delays, J. Differential Equations 179 (2002) 538-561].

Multiscale periodicities in aerosol optical depth over India

International Nuclear Information System (INIS)

Ramachandran, S; Ghosh, Sayantan; Verma, Amit; Panigrahi, P K

2013-01-01

Aerosols exhibit periodic or cyclic variations depending on natural and anthropogenic sources over a region, which can become modulated by synoptic meteorological parameters such as winds, rainfall and relative humidity, and long-range transport. Information on periodicity and phase in aerosol properties assumes significance in prediction as well as examining the radiative and climate effects of aerosols including their association with changes in cloud properties and rainfall. Periodicity in aerosol optical depth, which is a columnar measure of aerosol distribution, is determined using continuous wavelet transform over 35 locations (capitals of states and union territories) in India. Continuous wavelet transform is used in the study because continuous wavelet transform is better suited to the extraction of the periodic and local modulations present in various frequency ranges when compared to Fourier transform. Monthly mean aerosol optical depths (AODs) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Terra satellite at 1° × 1° resolution from January 2001 to December 2012 are used. Annual and quasi-biennial oscillations (QBOs) in AOD are evident in addition to the weak semi-annual (5–6 months) and quasi-triennial oscillations (∼40 months). The semi-annual and annual oscillations are consistent with the seasonal and yearly cycle of variations in AODs. The QBO type periodicity in AOD is found to be non-stationary while the annual period is stationary. The 40 month periodicity indicates the presence of long term correlations in AOD. The observed periodicities in MODIS Terra AODs are also evident in the ground-based AOD measurements made over Kanpur in the Indo-Gangetic Plain. The phase of the periodicity in AOD is stable in the mid-frequency range, while local disturbances in the high-frequency range and long term changes in the atmospheric composition give rise to unstable phases in the low-frequency range. The presence of phase

Orbital Period Changes in WZ Sagittae

Science.gov (United States)

Patterson, Joseph; Stone, Geoffrey; Kemp, Jonathan; Skillman, David R.; de Miguel, Enrique; Potter, Michael; Starkey, Donn; Uthas, Helena; Jones, Jim; Slauson, Douglas; Koff, Robert; Myers, Gordon; Menzies, Kenneth; Campbell, Tut; Roberts, George; Foote, Jerry; Vanmunster, Tonny; Cook, Lewis M.; Krajci, Thomas; Ogmen, Yenal; Sabo, Richard; Seargeant, Jim

2018-06-01

We report a long-term (1961–2017) study of the eclipse times in the dwarf nova WZ Sagittae, in an effort to learn its rate of orbital-period change. Some wiggles with a timescale of 20–50 years are apparent, and a connection with the ∼23 year interval between dwarf-nova eruptions is possible. These back-and-forth wiggles dominate the O–C diagram, and prevent a secure measurement of the steady rate of orbital-period change.

Replicate periodic windows in the parameter space of driven oscillators

Energy Technology Data Exchange (ETDEWEB)

Medeiros, E.S., E-mail: esm@if.usp.br [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil); Souza, S.L.T. de [Universidade Federal de Sao Joao del-Rei, Campus Alto Paraopeba, Minas Gerais (Brazil); Medrano-T, R.O. [Departamento de Ciencias Exatas e da Terra, Universidade Federal de Sao Paulo, Diadema, Sao Paulo (Brazil); Caldas, I.L. [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil)

2011-11-15

Highlights: > We apply a weak harmonic perturbation to control chaos in two driven oscillators. > We find replicate periodic windows in the driven oscillator parameter space. > We find that the periodic window replication is associated with the chaos control. - Abstract: In the bi-dimensional parameter space of driven oscillators, shrimp-shaped periodic windows are immersed in chaotic regions. For two of these oscillators, namely, Duffing and Josephson junction, we show that a weak harmonic perturbation replicates these periodic windows giving rise to parameter regions correspondent to periodic orbits. The new windows are composed of parameters whose periodic orbits have the same periodicity and pattern of stable and unstable periodic orbits already existent for the unperturbed oscillator. Moreover, these unstable periodic orbits are embedded in chaotic attractors in phase space regions where the new stable orbits are identified. Thus, the observed periodic window replication is an effective oscillator control process, once chaotic orbits are replaced by regular ones.

Polysheroidal periodic functions

International Nuclear Information System (INIS)

Truskova, N.F.

1985-01-01

Separation of variables in the Helmholtz N-dimensional (N≥4) equation in polyspheroidal coordinate systems leads to the necessity of solving equations going over into equations for polyspheroidal periodic functions used for solving the two-centre problem in quantum mechanics, the three-body problem with Coulomb interaction, etc. For these functions the expansions are derived in terms of the Jacobi polynomials and Bessel functions. Their basic properties, asymptotics are considered. The algorithm of their computer calculations is developed. The results of numerical calculations are given

Periodic trajectories for two-dimensional nonintegrable Hamiltonians

International Nuclear Information System (INIS)

Davies, K.T.R.

1990-02-01

I want to report on some calculations of classical periodic trajectories in a two-dimensional nonintegrable potential. After a brief introduction, I will present some details of the theory. The main part of this report will be devoted to showing pictures of the various families of trajectories and to discussing the topology (in E-τ space) and branching behavior of these families. Then I will demonstrate the connection between periodic trajectories and ''nearby'' nonperiodic trajectories, which nicely illustrates the relationship of this work to chaos. Finally, I will discuss very briefly how periodic trajectories can be used to calculate tori. 12 refs., 40 figs

Survival period, infectivity and morphological composition of ...

African Journals Online (AJOL)

Open Access DOWNLOAD FULL TEXT ... At the end of each maintenance period (hours), three clean albino mice were ... for up to 12 and 24 hours respectively were infective for the mice inoculation test. ... period (21.0days) higher peak parasitaemia (15-20 parasites per field) and higher population of slender forms.

Periodic safety analyses; Les essais periodiques

Energy Technology Data Exchange (ETDEWEB)

Gouffon, A; Zermizoglou, R

1990-12-01

The IAEA Safety Guide 50-SG-S8 devoted to 'Safety Aspects of Foundations of Nuclear Power Plants' indicates that operator of a NPP should establish a program for inspection of safe operation during construction, start-up and service life of the plant for obtaining data needed for estimating the life time of structures and components. At the same time the program should ensure that the safety margins are appropriate. Periodic safety analysis are an important part of the safety inspection program. Periodic safety reports is a method for testing the whole system or a part of the safety system following the precise criteria. Periodic safety analyses are not meant for qualification of the plant components. Separate analyses are devoted to: start-up, qualification of components and materials, and aging. All these analyses are described in this presentation. The last chapter describes the experience obtained for PWR-900 and PWR-1300 units from 1986-1989.

The period function of the generalized Lotka-Volterra centers

Science.gov (United States)

Villadelprat, J.

2008-05-01

The present paper deals with the period function of the quadratic centers. In the literature different terminologies are used to classify these centers, but essentially there are four families: Hamiltonian, reversible , codimension four Q4 and generalized Lotka-Volterra systems . Chicone [C. Chicone, Review in MathSciNet, Ref. 94h:58072] conjectured that the reversible centers have at most two critical periods, and that the centers of the three other families have a monotonic period function. With regard to the second part of this conjecture, only the monotonicity of the Hamiltonian and Q4 families [W.A. Coppel, L. Gavrilov, The period function of a Hamiltonian quadratic system, Differential Integral Equations 6 (1993) 1357-1365; Y. Zhao, The monotonicity of period function for codimension four quadratic system Q4, J. Differential Equations 185 (2002) 370-387] has been proved. Concerning the family, no substantial progress has been made since the middle 80s, when several authors showed independently the monotonicity of the classical Lotka-Volterra centers [F. Rothe, The periods of the Volterra-Lokta system, J. Reine Angew. Math. 355 (1985) 129-138; R. Schaaf, Global behaviour of solution branches for some Neumann problems depending on one or several parameters, J. Reine Angew. Math. 346 (1984) 1-31; J. Waldvogel, The period in the Lotka-Volterra system is monotonic, J. Math. Anal. Appl. 114 (1986) 178-184]. By means of the first period constant one can easily conclude that the period function of the centers in the family is monotone increasing near the inner boundary of its period annulus (i.e., the center itself). Thus, according to Chicone's conjecture, it should be also monotone increasing near the outer boundary, which in the Poincaré disc is a polycycle. In this paper we show that this is true. In addition we prove that, except for a zero measure subset of the parameter plane, there is no bifurcation of critical periods from the outer boundary. Finally we

Engineering of spatial solitons in two-period QPM structures

DEFF Research Database (Denmark)

Johansen, Steffen Kjær; Carrasco, Silvia; Torner, Lluis

2002-01-01

We report on a scheme which might make it practically possible to engineer the effective competing nonlinearities that on average govern the light propagation in quasi-phase-matching (QPM) gratings. Modulation of the QPM period with a second longer period, introduces an extra degree of freedom...... relative lengths of the two periods and we consider the effect on solitons and the bandwidth for their generation. We derive an expression for the bandwidth of multicolor soliton generation in two-period QPM samples and we predict and confirm numerically that the bandwidth is broader in the two-period QPM...

Period of an Interrupted Pendulum

Science.gov (United States)

Miller, Bradley E.

2002-11-01

While demonstrating a classic conservation-of-energy problem to my AP Physics students, I became curious about the periodic motion that ensued for certain initial conditions. The original problem consists of releasing a mass at the end of a string from an initial position horizontal to the plane of a table. The string comes in contact with a peg some distance below the point where the string is attached at the top. One is asked to find what minimum fraction of the string's length should the peg be placed to have the mass complete a circle about the peg. However, when the mass is released from much lower heights, the system undergoes periodic motion that can be thought of as an interrupted pendulum.

Periodicity of the stable isotopes

CERN Document Server

Boeyens, J C A

2003-01-01

It is demonstrated that all stable (non-radioactive) isotopes are formally interrelated as the products of systematically adding alpha particles to four elementary units. The region of stability against radioactive decay is shown to obey a general trend based on number theory and contains the periodic law of the elements as a special case. This general law restricts the number of what may be considered as natural elements to 100 and is based on a proton:neutron ratio that matches the golden ratio, characteristic of biological and crystal growth structures. Different forms of the periodic table inferred at other proton:neutron ratios indicate that the electronic configuration of atoms is variable and may be a function of environmental pressure. Cosmic consequences of this postulate are examined. (author)

Evaluation of the Use of Periodicals Collection of the Higher Education Council Documentation and Online Search Center: Arts and Humanities Periodicals

Directory of Open Access Journals (Sweden)

Elçin Özbudak

1995-06-01

Full Text Available Evaluation of the use perodicals collections in libraries is important as perodicals report the results of the latest scientific research and they are usually more expensive than other types of library materials. In this study we evaluate the use of Arts and Humanities periodicals in the collection of the Higher Education Council Documentation Center. Although the use of Arts and Humanities periodicals was found to be lower than, say, Biomedical periodicals collection, the number of journal titles in Arts and Humanities appears to be quite satisfactory. Some suggestions are made so as to increase the use of Arts and Humanities periodicals collection.

Periodic transients linked to a variation in reactivity; Transitoires de periode lies a une variation de reactivite

Energy Technology Data Exchange (ETDEWEB)

Furet, J; Weil, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

We study here the influence of the transient, linked to a variation in reactivity, on the measurement of the period, this measurement being made from the logarithmic differential of the power and being defined by 1/T 1/p(dp/dt). We show that the adjustment of the thresholds of period safety is often incompatible with the velocities of liberation of reactivity. A compromise is then necessary between the speed of response of the periodimeter and the speed with which the reactivity is liberated. This makes it necessary to have rapid security devices for the power levels in the piles in which the speeds of liberation of the reactivity are high. (author) [French] On etudie ici l'influence du transitoire lie a une variation de la reactivite sur la mesure de la periode, cette mesure etant faite a partir de la derivee logarithmique de la puissance et etant definie par 1/T 1/p(dp/dt). On montre que le reglage des seuils de securite periode est souvent incompatible avec les vitesses de liberation de reactivite. Il y a alors un compromis a faire entre la vitesse de reponse du periodemetre et la vitesse de liberation de reactivite. Ceci impose de disposer de securites rapides sur les niveaux de puissance, dans les piles ou les vitesses de liberation de reactivite sont importantes. (auteur)

14 CFR Sec. 2-4 - Accounting period.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Accounting period. Sec. 2-4 Section 2-4... REGULATIONS UNIFORM SYSTEM OF ACCOUNTS AND REPORTS FOR LARGE CERTIFICATED AIR CARRIERS General Accounting Provisions Sec. 2-4 Accounting period. (a) The accounting year of each air carrier subject to this Uniform...

Real space method of powder diffraction for non-periodic and nearly periodic materials

International Nuclear Information System (INIS)

Egami, T.; Toby, B.H.; Dmowski, W.; Janot, C.; Jorgensen, J.D.

1990-01-01

The use of high-energy neutrons from pulsed or hot sources allows the method of atomic pair distribution analysis to be applied to the structural determination of crystalline as well as amorphous solids. This method complements the standard crystallographic methods in studying non-periodic aspects of solids with or without long range order

The next step in biology: a periodic table?

Science.gov (United States)

Dhar, Pawan K

2007-08-01

Systems biology is an approach to explain the behaviour of a system in relation to its individual components. Synthetic biology uses key hierarchical and modular concepts of systems biology to engineer novel biological systems. In my opinion the next step in biology is to use molecule-to-phenotype data using these approaches and integrate them in the form a periodic table. A periodic table in biology would provide chassis to classify, systematize and compare diversity of component properties vis-a-vis system behaviour. Using periodic table it could be possible to compute higher- level interactions from component properties. This paper examines the concept of building a bio-periodic table using protein fold as the fundamental unit.

26 CFR 301.7609-5 - Suspension of periods of limitations.

Science.gov (United States)

2010-04-01

... accountant for B, requiring production of records relating to B's income tax liabilities for 2003. The... prosecutions) for the tax period or periods that are the subject of the summons are suspended for the period... 6501 and 6531 for the tax period or periods that are the subject of the summons are suspended for the...

Comparative study of optical properties of the one-dimensional multilayer Period-Doubling and Thue-Morse quasi-periodic photonic crystals

Directory of Open Access Journals (Sweden)

Y. Bouazzi

2012-10-01

Full Text Available The last decades have witnessed the growing interest in the use of photonic crystal as a new material that can be used to control electromagnetic wave. Actually, not only the periodic structures but also the quasi-periodic systems have become significant structures of photonic crystals. This work deals with optical properties of dielectric Thue-Morse multilayer and Period-Doubling multilayer. We use the so-called Transfer Matrix Method (TMM to determine the transmission spectra of the structures. Based on the representation of the transmittance spectra in the visible range a comparative analysis depending on the iteration number, number of layers and incidence angle is presented.

Sex and ancestry determine the free-running circadian period.

Science.gov (United States)

Eastman, Charmane I; Tomaka, Victoria A; Crowley, Stephanie J

2017-10-01

The endogenous, free-running circadian period (τ) determines the phase relationship that an organism assumes when entrained to the 24-h day. We found a shorter circadian period in African Americans compared to non-Hispanic European Americans (24.07 versus 24.33 h). We speculate that a short circadian period, closer to 24 h, was advantageous to humans living around the equator, but when humans migrated North out of Africa, where the photoperiod changes with seasons, natural selection favoured people with longer circadian periods. Recently, in evolutionary terms, immigrants came from Europe and Africa to America ('the New World'). The Europeans were descendents of people who had lived in Europe for thousands of years with changing photoperiods (and presumably longer periods), whereas Africans had ancestors who had always lived around the equator (with shorter periods). It may have been advantageous to have a longer circadian period while living in Europe early in the evolution of humans. In our modern world, however, it is better to have a shorter period, because it helps make our circadian rhythms earlier, which is adaptive in our early-bird-dominated society. European American women had a shorter circadian period than men (24.24 versus 24.41), but there was no sex difference in African Americans (24.07 for both men and women). We speculate that selection pressures in Europe made men develop a slightly longer period than women to help them track dawn which could be useful for hunters, but less important for women as gatherers. © 2017 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Unstable Angina Treatment in Various Periods of Geomagnetic Activity

Science.gov (United States)

Parshina, S. S.; Tokayeva, L. K.; Afanasiyeva, T. N.; Samsonov, S. N.; Petrova, V. D.; Dolgova, E. M.; Manykina, V. I.; Vodolagina, E. S.

In 145 patients with unstable angina (UA) there was analized an efficiency of a drug therapy at different types of heliogeophysical activity (HA) during the 23th solar cycle. 83 patients were examined at the period of a lower HA (Kp-index 16,19±0,18), and 62 patients - at the period of a higher HA (Kp-index 17,25±0,21, p<0,05). Baseline severity of patients' condition with UA at the moment of hospitalization at the studied periods did not differ, but the effectiveness of the therapy depended on the period of HA. At the period of a higher HA antianginal effect was stronger than at the lower period of HA (2,27±0,16 points and 1,75±0,12 points, p<0,05), and the need in nitroglycerin on the background of a drug therapy disappeared for 5-7 days quicker than at the period of a lower HA. Maximal hypotensive effect at a higher HA was achieved quicker - on the 3rd day of the treatment, and at a lower HA - only up to hospital discharge (p<0,05). Blood viscosity did not normalize in both of the studied periods, but in small vessels there was noted a decrease of a BV (p<0,05). So, at a higher HA the effectiveness of a drug therapy in patients with UA is higher than at the period of a lower HA.

Buffer Overflow Period in a MAP Queue

Directory of Open Access Journals (Sweden)

Andrzej Chydzinski

2007-01-01

Full Text Available The buffer overflow period in a queue with Markovian arrival process (MAP and general service time distribution is investigated. The results include distribution of the overflow period in transient and stationary regimes and the distribution of the number of cells lost during the overflow interval. All theorems are illustrated via numerical calculations.

Unified Digital Periodic Signal Filters for Power Converter Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Xin, Zhen; Zhou, Keliang

2017-01-01

Periodic signal controllers like repetitive and resonant controllers have demonstrated much potential in the control of power electronic converters, where periodic signals (e.g., ac voltages and currents) can be precisely regulated to follow references. Beyond the control of periodic signals, ac...... signal processing (e.g., in synchronization and pre-filtering) is also very important for power converter systems. Hence, this paper serves to unify digital periodic signal filters so as to maximize their roles in power converter systems (e.g., enhance the control of ac signals). The unified digital...... periodic signal filters behave like a comb filter, but it can also be configured to selectively filter out the harmonics of interest (e.g., the odd-order harmonics in single-phase power converter systems). Moreover, a virtual variable-sampling-frequency unit delay that enables frequency adaptive periodic...

Resonances in a periodically driven bosonic system

Science.gov (United States)

Quelle, Anton; Smith, Cristiane Morais

2017-11-01

Periodically driven systems are a common topic in modern physics. In optical lattices specifically, driving is at the origin of many interesting phenomena. However, energy is not conserved in driven systems, and under periodic driving, heating of a system is a real concern. In an effort to better understand this phenomenon, the heating of single-band systems has been studied, with a focus on disorder- and interaction-induced effects, such as many-body localization. Nevertheless, driven systems occur in a much wider context than this, leaving room for further research. Here, we fill this gap by studying a noninteracting model, characterized by discrete, periodically spaced energy levels that are unbounded from above. We couple these energy levels resonantly through a periodic drive, and discuss the heating dynamics of this system as a function of the driving protocol. In this way, we show that a combination of stimulated emission and absorption causes the presence of resonant stable states. This will serve to elucidate the conditions under which resonant driving causes heating in quantum systems.

Resonances in a periodically driven bosonic system.

Science.gov (United States)

Quelle, Anton; Smith, Cristiane Morais

2017-11-01

Periodically driven systems are a common topic in modern physics. In optical lattices specifically, driving is at the origin of many interesting phenomena. However, energy is not conserved in driven systems, and under periodic driving, heating of a system is a real concern. In an effort to better understand this phenomenon, the heating of single-band systems has been studied, with a focus on disorder- and interaction-induced effects, such as many-body localization. Nevertheless, driven systems occur in a much wider context than this, leaving room for further research. Here, we fill this gap by studying a noninteracting model, characterized by discrete, periodically spaced energy levels that are unbounded from above. We couple these energy levels resonantly through a periodic drive, and discuss the heating dynamics of this system as a function of the driving protocol. In this way, we show that a combination of stimulated emission and absorption causes the presence of resonant stable states. This will serve to elucidate the conditions under which resonant driving causes heating in quantum systems.

Systematic Onset of Periodic Patterns in Random Disk Packings

Science.gov (United States)

Topic, Nikola; Pöschel, Thorsten; Gallas, Jason A. C.

2018-04-01

We report evidence of a surprising systematic onset of periodic patterns in very tall piles of disks deposited randomly between rigid walls. Independently of the pile width, periodic structures are always observed in monodisperse deposits containing up to 1 07 disks. The probability density function of the lengths of disordered transient phases that precede the onset of periodicity displays an approximately exponential tail. These disordered transients may become very large when the channel width grows without bound. For narrow channels, the probability density of finding periodic patterns of a given period displays a series of discrete peaks, which, however, are washed out completely when the channel width grows.

Periodic trajectories for a two-dimensional nonintegrable Hamiltonian

International Nuclear Information System (INIS)

Baranger, M.; Davies, K.T.R.

1987-01-01

A numerical study is made of the classical periodic trajectories for the two-dimensional nonintegrable Hamiltonian H = 1/2(p 2 /sub x/+p 2 /sub y/)+(y-1/2x 2 ) 2 +0.05 x 2 . In addition to x--y pictures of the trajectories, E--tau (energy--period) plots of the periodic families are presented. Efforts have been ade to include all trajectories with short periods and all simple branchings of these trajectories. The monodromy matrix has been calculated in all cases, and from it the stability properties are derived. The topology of the E--tau plot has been explored, with the following results. One family may have several stable regions. The plot is not completely connected; there are islands. The plot is not a tree; there are cycles. There are isochronous branchings, period-doublings, and period-multiplyings of higher orders, and examples of each of these are presented. There is often more than one branch issuing from a branch point. Some general empirical rules are inferred. In particular, the existence of isochronous branching is seen to be a consequence of the symmetry of the Hamiltonian. All these results agree with the general classification of possible branchings derived in Ref. [10]. (M. A. M. de Aguiar, C. P. Malta, M. Baranger, and K. T. R. Davies, in preparation). Finally, some nonperiodic trajectories are calculated to illustrate the fact that stable periodic trajectories lie in ''regular'' regions of phase space, while unstable ones lie in ''chaotic'' regions

Further results on periods and period doubling for iterates of the trapezoic function

International Nuclear Information System (INIS)

Beyer, W.A.; Stein, P.R.

1982-01-01

The trapezoidal function lambda f/sub e/(x), is defined for fixed e element of (0,1] and for lambda element of [1,2] by lambda f/sub e/ (x) = lambda for /x-1/< 1-e and lambda f/sub e/(x) = lambda(1-/x-1/)/(1-e) for 1 greater than or equal to /x-1/greater than or equal to 1-e. For a fixed e, this is a one parameter family of endomorphisms of the interval [0,2]. The structure of the periods (or cycles) of these mappings is studied. In addition, the metric properties of the corresponding bifurcation diagrams are considered; in particular, the rate of convergence of a sequence of bifurcation points in the (x,lambda) plane is studied. It is shown to be different from that found by Feigenbaum and others for mappings which are not flat at the top. The limiting case e = 1 is of special interest. For cycles and containing a point x element of[e,2-e], the period quadruplicates instead of doubling as it does in the usual case