Universal features of counting statistics of thermal and quantum phase slips in nanosize superconducting circuits

We perform measurements of phase-slip-induced switching current events on different types of superconducting weak links and systematically study statistical properties of the switching current distributions. We employ two types of devices in which a weak link is formed either by a superconducting nanowire or by a graphene flake subject to proximity effect. We demonstrate that independently of the nature of the weak link, higher moments of the distribution take universal values. In particular, the third moment (skewness) of the distribution is close to -1 both in thermal and quantum regimes. The fourth moment (kurtosis) also takes a universal value close to 5. The discovered universality of skewness and kurtosis is confirmed by an analytical model. Our numerical analysis shows that introduction of extraneous noise into the system leads to significant deviations from the universal values. We suggest using the discovered universality of higher moments as a robust tool for checking against undesirable effects on noise in various types of measurements.

Ensiling olive cake with and without molasses for ruminant feeding

The purpose of the current experiment was to study the ensiling properties of olive cake with and without added molasses at 2-6% (w/w). The results indicate that molasses enhanced the ensiling fermentation of olive cake, as evidenced from higher lactic acid content and higher lactic acid bacteria numbers at 4% and 6% added molasses. However, when applied at 4% and 6% molasses increased fermentation losses up to 9.4%, probably due to larger yeast population. Polyphenols which could interfere with protein utilization by ruminants, decreased during ensiling by about 40%. It is concluded that molasses added at 3% could improve the ensiling fermentation of olive cake without substantial losses.

[Absorption of L-lysine diatrizoate from the gastrointestinal tract: the influence of surgery, inflammation and neoplasia]

PURPOSE

To ascertain whether the absorption of L-lysine diatrizoate, a sodium-free salt of the contrast-giving diatrizoic acid, from the gastrointestinal tract is increased by surgery, inflammation or neoplasia.

MATERIAL AND METHODS

Using contrast medium containing L-lysine diatrizoate for intestinal opacification, this prospective study compared 32 radiographic examinations of the upper gastrointestinal tract with 52 radiographic examination of the lower gastrointestinal tract. In blood samples taken from the patients immediately after the radiographic examinations, the concentration of diatrizoic acid was determined by high pressure liquid chromatography. The results were correlated with sex, age, surgical history and any evidence of inflammatory or neoplastic diseases.

RESULTS

The serum diatrizoic acid concentration in patients after oral administration was 3.62 (95% CI, 2.86 - 10.17) microg/ml. The titer was lower in patients who had undergone abdominal surgery than in patients without surgery. Serum diatrizoic acid concentration in patients after rectal administration was 0.30 (95% CI, 0.13 - 0.60) microg/ml. The titer was significantly higher (p < 0.05) in patients suffering from inflammatory conditions or neoplasms than in the other patients.

CONCLUSION

The L-lysine salt of diatrizoic acid is absorbed in larger amounts from the upper than from the lower gastrointestinal tract. Absorption is not increased after abdominal surgery. However, inflammatory conditions and neoplasms of the large bowel increase the uptake of contrast medium from the intestine.

Deviation of atrial septum primum in association with normal left atrioventricular valve size

Deviation of atrial septum primum (DASP) is an unusual anatomic finding in patients with normal left atrioventricular valve size. To better describe this anomaly, we reviewed our echocardiographic database from January 1987 to May 1999. Twenty-four patients had DASP and a normal-sized left atrioventricular valve. Six had inferior DASP with common atrioventricular canal. Of these, 3 had evidence of left atrial outlet obstruction. Five survived surgical intervention with follow-up of 24 +/- 14 months. Seventeen patients had superoposterior deviation with the right pulmonary veins draining anomalously to the right atrium. Only 8 of 17 underwent surgical resection; none of the 17 have evidence for late development of obstruction. One patient had both inferior deviation and superoposterior DASP and underwent early successful repair. DASP occurs in patients with normal left atrioventricular valve size. Inferior DASP can result in left atrial outlet obstruction and requires surgical intervention. Superoposterior DASP carries less physiologic consequence. Echocardiography can distinguish this anomaly from other forms of left atrial obstruction.

[Parotid schwannoma]

We present the case of a 13-year-old boy with intra-parotid schwannoma of the facial nerve. We discuss the histopathology, preoperative diagnosis by fine needle aspiration cytology, and surgical strategy.

Decreased heart rate variability in panic disorder patients: a study of power-spectral analysis of heart rate

We have previously found decreased standard deviations and mean consecutive differences of R-R intervals in panic disorder patients in standing posture, compared with control subjects. In the present study, we used spectral analysis of heart rate variability to examine autonomic function in 21 panic disorder patients and 21 normal control subjects. Patients had a significantly lower standard deviation of heart rate in supine as well as standing postures. Absolute low frequency power (0.01-0.05 Hz) was also significantly lower in panic disorder patients in standing postures. Upon standing, the panic disorder patients had significantly higher relative mid-frequency power (0.07-0.15 Hz). During a standing deep-breathing condition at six breaths per minute, the patients had a significantly decreased absolute and relative mid-frequency (0.07-0.15 Hz) power compared with control subjects. These findings suggest a decrease in cholinergic and a relative increase in adrenergic responsiveness in panic disorder patients compared with control subjects.

Effects of yohimbine on heart rate variability in panic disorder patients and normal controls: a study of power spectral analysis of heart rate

We studied the effects of yohimbine on heart rate (HR) variability in 13 normal controls and 13 patients with panic disorder. Yohimbine produced a significant increase in SD of HR in standing posture in both patients (p = 0.01) and normal controls (p = 0.025). Panic disorder patients had a significant increase in standing absolute midfrequency (MF) power (0.07-0.15 Hz) after administration of yohimbine (p = 0.002). The ratio of post- to preyohimbine standing MF power (0.07-0.15 Hz) during standing was significantly higher in patients as compared with controls (2.3 +/- 1.08 vs. 1.33 +/- 0.38; p = 0.01), which suggests an increased responsivity of panic disorder patients to the adrenergic effects of yohimbine.

Leftward shift of R-axis on electrocardiogram in patients with panic disorder and depression

In a prospective study, we have compared R-axis on routine electrocardiograms of panic disorder patients (n = 52) with that of depressed patients (n = 41) and normal controls (n = 65). All subjects were physically healthy and were normotensive. There was a significant leftward shift of R-axis in both depressed and panic disorder patients compared to normal controls. The implications of these findings are discussed.

Effect of imipramine treatment on heart rate variability measures

Recently, heart rate (HR) variability has received considerable attention, and a decreased HR variability has been linked to a significant risk of cardiovascular illness. We have previously reported such a decreased variability in panic disorder patients. In this study, we report on HR variability in 12 depressed and 6 panic disorder patients at baseline and 1 and 3 weeks of treatment with imipramine as measured by the standard deviation, mean consecutive difference and the standard deviation of the mean consecutive difference of the R-R intervals in supine, supine deep breathing and standing postures. In all subjects, imipramine (mean dose: 70 mg/day) produced a significant decrease in heart rate variability at week 3 as measured by the above variables. This decrease in HR variability during imipramine treatment is probably due to its anticholinergic effects.

Imipramine-induced jitteriness and decreased serum iron levels

Jitteriness appears to be a specific side effect of tricyclic antidepressant treatment in panic disorder patients. In addition, the patients with jitteriness have lower serum iron levels compared to those that do not develop jitteriness (p = 0.01).

The effect of osmotic and mechanical pressures on water partitioning in articular cartilage

X-ray diffraction measurements on native and proteoglycan-free articular cartilage have been made in order to test the dependence of the lateral packing of the collagen molecules on the osmotic pressure gradient, either naturally occurring or externally applied, between the intra- and extrafibrillar compartments. From the information on collagen packing we have been able to calculate, albeit with several assumptions, the amount of intrafibrillar water as a function of pressure. In parallel with the above measurements, we have quantitated, using serum albumin partitioning, the intrafibrillar water in proteoglycan-free cartilage, as a function of mechanically applied pressure. The results of both sets of experiments lead to the conclusion that the molecular packing density, and hence the intrafibrillar water content, are a function of the osmotic pressure difference between the extrafibrillar and intrafibrillar spaces or the equivalent mechanically applied pressure. The determination of intrafibrillar water has enabled us to calculate, from measured values of fixed charge density, the internal osmotic pressure of cartilage specimens, both in compressed and uncompressed states.

Hemodynamic effects of high-frequency jet ventilation in dogs with acute right coronary arterial ligation and pulmonary arterial banding

The hemodynamic effects of high-frequency jet ventilation (HFJV), synchronized with diastole, and intermittent positive-pressure ventilation (IPPV) were studied in 10 dogs with acute right-sided myocardial ischemia and elevated right ventricular pressure. Myocardial ischemia was produced by ligation of the proximal right coronary artery (RCA), then the right ventricular pressure was elevated to facilitate the ischemia by banding the main pulmonary artery. Before and 1, 2, 3, and 5 hr after the RCA ligation, cardiorespiratory variables for each ventilatory mode and creatine phosphokinase MB isoenzyme (CPK-MB) were measured. During HFJV compared with IPPV: there were significant increases in stroke index and left ventricular stroke work index at all ischemic periods, and decreases in peak and mean airway pressures and pulmonary vascular resistance at all ischemic periods, and in the product of systolic right ventricular pressure and heart rate at 2 hr, 3 hr, and 5 hr. The difference in mean airway pressure between IPPV and HFJV correlated significantly with those in cardiac index and stroke index (r = 0.575 and 0.779, respectively). CPK-MB was significantly greater at 3 hr and 5 hr than that before RCA ligation. These findings suggest that HFJV synchronized with diastole offers hemodynamic advantages over IPPV to ischemic right ventricle with constricted pulmonary artery, mainly due to lowering the mean airway pressure.

Decreased R-R variance in panic disorder patients

To investigate autonomic function in panic disorder patients (n = 30), we compared postural changes in heart rate and the R-R interval variance in patients and normal controls (n = 20). There was no significant difference in the immediate changes in heart rate upon standing between the groups. R-R variance was significantly decreased during resting supine condition in patients as indicated by the corrected standard deviation of the R-R intervals. The standing R-R variance was significantly lower than that of normal controls as indicated by the corrected standard deviations, the corrected mean consecutive difference and the corrected standard deviation of the mean consecutive difference of the R-R intervals, suggesting an increase in vagal withdrawal in patients, especially upon standing. If this finding is specific to panic disorder patients, it may be a useful peripheral marker for this condition.

Neuroblastoma and DiGeorge anomaly

DiGeorge anomaly is a rare disorder felt to be a complex neurocristopathy. We report the unusual association of congenital neuroblastoma arising in an infant with the DiGeorge anomaly.

Holt-Oram syndrome associated with the hypoplastic left heart syndrome

We present the first case of Holt-Oram syndrome associated with the lethal congenital heart defect of hypoplastic left heart syndrome. The possible pathophysiological link is explored and the need for careful genetic and cardiologic evaluation in these patients is reiterated.

Isoproterenol-induced panic attacks

Eighty-six panic disorder patients and 45 nonpsychiatric controls were infused with isoproterenol at a rate of 1 microgram/min for up to 20 min in a placebo-controlled, double-blind study. Sixty-six percent of panic disorder patients experienced panic attacks during isoproterenol infusions, compared to 16% during placebo infusions. Nine percent of control subjects panicked with isoproterenol, but none panicked with placebo. Patients were more sensitive than controls to the anxiogenic effects of isoproterenol, as measured by subject self-ratings on a panic description scale. The frequency of panic attacks induced in patients was related to the dosage of isoproterenol; 79% of the patients who received a mean of 18.5 ng/min/kg of isoproterenol panicked. The panic attacks experienced by patients during isoproterenol infusions were similar to those experienced during placebo infusions.

Lactate- and isoproterenol-induced panic attacks in panic disorder patients and controls

In a double-blind study using sodium lactate and isoproterenol infusions to provoke panic attacks, 73 of 86 panic disorder patients and 10 of 45 controls panicked with lactate, and 58 of 86 patients and 4 of 45 controls panicked with isoproterenol. We measured baseline and peak anxiety ratings in 10 controls with lactate-induced panic attacks, 31 controls who did not panic during lactate infusions, and 63 panic disorder patients who did panic during lactate infusions. The controls who panicked with lactate had robust increases in their anxiety ratings very similar to the increases experienced by patients who panicked with lactate.

Thyroid hormone levels in panic disorder

A history of thyroid dysfunction has been reported in patients with phobic disorders. There is also evidence of a blunted TSH response to TRH stimulation in patients with panic disorder. In this study, values of T3, T4 and T7 were compared between 26 patients with panic attacks and 20 normal controls. Patients were diagnosed according to DSM-III criteria and those with a clinical history of thyroid dysfunction were excluded. Patients were not on any medication when the blood samples were drawn. The mean values of T3, T4 and T7 did not significantly differ between the two groups, suggesting no evidence of hypo or hyperthyroidism; however, the variance of distribution of T3, T4 and T7 values was significantly different between the two groups (Fmax values for T3: 2.55, p value less than 0.05; T4: 3.15, p value less than 0.01; T7: 2.55, p value less than 0.05).

Preinfusion anxiety predicts lactate-induced panic attacks in normal controls

Preinfusion anxiety, heart rate, and blood pressure were measured in 31 normal subjects who received sodium lactate infusions. Eight subjects developed symptoms of panic anxiety during these infusions. Preinfusion anxiety as measured by psychologic symptoms of anxiety on the Panic Description Scale was significantly higher in the panickers while heart rate and blood pressure were not.

Do higher preinfusion heart rates predict laboratory-induced panic attacks?

Baseline and preinfusion heart rates of 13 panic disorder patients who panicked during a placebo infusion were not significantly different from those of 57 panic disorder patients who did not panic during a placebo infusion. The change in preinfusion heart rates from baseline values also was not significantly different between the two groups.

Twice-daily nicardipine in the treatment of essential hypertension

The antihypertensive effect of twice-daily nicardipine, an investigational calcium-channel blocker, was evaluated in a placebo-controlled, single-blind trial in 18 adult patients with essential hypertension (supine diastolic blood pressure [BP] of greater than or equal to 95 and less than or equal to 120 mmHg). Following a 4-week run-in period in which patients received placebo for the final 2 weeks, nicardipine was administered for 12 weeks with a treatment goal of a supine diastolic BP of less than 90 mmHg at 12 hours postdosing or to a maximum dose of 60 mg twice daily. Supine and standing BPs and heart rates were determined at 1 hour and 12 hours postdosing. At all dose levels, supine and standing BPs were reduced at 1 hour after dosing, with partial loss of efficacy seen at 12 hours. Increases in heart rate seen at 1 hour were not significant at 12 hours. Eight patients withdrew from the study for minor, although troublesome, side effects, such as palpitations and headaches. These data suggest that nicardipine monotherapy given in a twice-daily dosing regimen has only a limited role to play in the chronic treatment of patients with essential hypertension.

Twice-daily administration of oral verapamil in the treatment of essential hypertension

The antihypertensive effect of twice-daily administration of verapamil hydrochloride was evaluated in 21 adult patients with mild to moderate essential hypertension. Following four weeks of placebo therapy, verapamil was given for four weeks with a treatment goal of sitting diastolic blood pressure (BP) of less than 90 mm Hg, or to a maximum dose of 160 mg twice daily. Sitting and standing BPs, heart rate, and verapamil plasma levels were determined weekly, ten to 12 hours post dose. At the maximal dose (mean, 154 +/- 19.2 mg), heart rate was not affected, side effects were minimal, and sitting diastolic BP was significantly reduced from placebo baseline, with 12 of 21 patients having a fall in sitting diastolic BP of 10 mm Hg or more or less than 90 mm Hg. A trough verapamil plasma level of greater than 80 ng/mL was associated with a good hypotensive response. These data indicate the safety and utility of twice-daily verapamil administration for the treatment of essential hypertension and suggest the value of obtaining verapamil plasma levels as a guide to dosage determination.

Calcium entry blockers for the treatment of severe hypertension and hypertensive crisis

Calcium entry blockers (diltiazem, nifedipine, and verapamil) are currently indicated for the treatment of patients with vasospastic and chronic stable angina pectoris. The calcium entry blocking actions of these drugs cause potent peripheral vasodilatory and antihypertensive effects in human subjects. The drugs have proved beneficial in the treatment of patients with severe hypertension and hypertensive emergencies. Single oral, sublingual, and intravenous doses of these drugs have been shown to rapidly and smoothly reduce blood pressure in adults and children, without significant untoward effects. The absolute reduction in blood pressure with treatment appears to be inversely correlated with the pretreatment blood pressure level, and few episodes of hypotension have been reported. Combinations of calcium entry blockers with other antihypertensive regimens have also proved effective. Some patients experience a mild increase in heart rate with nifedipine, an effect that appears to be inversely related to age. Side effects are minimal and not life-threatening. Continuous hemodynamic monitoring of patients does not seem necessary in most cases. The role of calcium entry blockade in the treatment of hypertensive emergencies still needs to be established in relation to other available approved drug regimens for this condition.

The beta-receptor: isoproterenol anxiety states

To learn the effect of isoproterenol on patients meeting Research Diagnostic Criteria (RDC) for panic disorder, we administered isoproterenol, racemic sodium lactate, and glucose to them and to nonpsychiatric control subjects. Each subject received all 3 infusions, double-blind in random order. A 21-item self-rating panic scale was constructed from the RDC for panic disorder and was used to identify RDC panic attacks. The results of this study and the preliminary results from the infusions after treatment with imipramine are discussed in the text, and the results from the first patient to be reinfused after treatment are presented graphically.

Aortopulmonary window and aortic isthmic hypoplasia. Operative management in newborn infants

Aortopulmonary window with aortic isthmic hypoplasia is an unusual combination of congenital heart lesions that usually causes severe heart failure, poor systemic perfusion, and death shortly after birth. In 21 previously reported cases, survival beyond infancy was uncommon, yet only one neonate survived operation. This report describes three cases of aortopulmonary window and aortic isthmic hypoplasia and a two-stage operative approach that proved successful in both infants in which it was tried. During the first step the isthmic obstruction is relieved, the ductus is ligated, and the aortopulmonary window is plicated via a left thoracotomy. The second stage consists of definitive closure of the aortopulmonary window using the technique of deep perfusion hypothermia.

Vascular ring: left cervical aortic arch, right descending aorta, and right ligamentum arteriosum

A rare form of vascular ring is presented consisting of a left cervical aortic arch, a right descending aorta, and a right ligamentum arteriosum in a symptomatic infant. The planning of its surgical interruption was complicated by absence of the left pulmonary artery and hypoplasia of the left lung. This case provides an exception to the surgical axiom that all vascular rings can be divided through the left side of the chest. It reveals the difficulty in evaluation of these lesions by barium swallow alone and emphasizes the importance of preoperative angiography to correctly define the anatomy. The surgical approach to a patient with an absent left pulmonary artery and hypoplastic lung requiring a contralateral thoracotomy is presented.

Subclavian--left coronary artery anastomosis (Meyer operation) for anomalous origin of the left coronary artery from the pulmonary artery

Six patients, ages 2--76 months, had subclavian--coronary artery anastomosis (the Meyer operation) through a left thoracotomy without cardiopulmonary bypass for anomalous origin of the left coronary artery. Five of the six had congestive heart failure and ischemic abnormalities on the ECG. All six had cardiomegaly by chest x-ray. Preoperative left ventricular rejection reactions averaged 0.46 +/- 0.171. In three patients in whom peak systolic pressure was measured in the left coronary artery at operation, pressure increased by a mean of 26 mm Hg when the anastomosis was unclamped. One patient died. Five patients are alive 8--92 months postoperatively and four of the five anastomoses were patent at postoperative cardiac catheterization. Postoperative ECGs were normal or showed reduced T-wave abnormalities in all patients, and heart size by chest x-ray has decreased or is normal. Postoperative ejection fractions increased by a mean of 0.12 in four of the five patients (p = 0.01). On patient had a normal ejection fraction preoperatively and it remained unchanged postoperatively. No patient receives cardiac medications or is symptomatic at late follow-up. The Meyer operation can be performed at an early age, establishes a two-coronary-artery system, has growth potential, requires one vascular anastomosis, and in this series, resulted in reversal of left ventricular ischemic changes and improvement in left ventricular contractility.

A combined approach for the diagnosis of orbital disease. Computed tomography and standardized A-scan echography

Twenty patients with orbital disease were studied by both computed tomography (CT scan) and standardized A-scan echography (ultrasonography). The CT scan was distinctly abnormal in 15 cases: 11/11 tumors were identified; a large wooden foreign body was identified; and nonspecific abnormal radiodensities were shown in three additional casses. Standardized A-scan echography, however, was capable of demonstrating the abnormality in all 20: in nine orbital tumors, a preoperative histologic diagnosis was attempted and proven accurate in all nine (in two no histologic disgnosis was attempted); and nontumor soft tissue abnormalities were equally readily classified. The overall diagnostic capability, therefore, in our series is 19/20 with a tissue diagnosis achieved on echographic bases in 17/20. (One case is excluded from this analysis as unexplained unilateral papilledema has been the only abnormality found and orbital abnormalities per se have not been proven.) We believe the roles of these two valuable diagnostic modalities to be complementary, not mutually exclusive, and conclude thet this combined radiologic and echographic approach to orbital abnormalities is essential to the proper evaluation of orbital disease.