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The amplification of the relative Fresnel (Goos-Haenchen) phase by an appropriate number of total internal reflections and the choice of favorable incidence angles allow to observe full oscillations in the power of a DPSS laser transmitted through sequential BK7 blocks. The experimental results confirm the theoretical predictions. The optical apparatus used in this letter can be seen as a new type of two-phase ellipsometric system where the phase of the complex refractive index is replaced by the relative Fresnel (Goos-Haenchen) phase., 7 pages, 3 figures, 1 table

WOS: 000442229500021, PubMed ID: 30101073, Background: In infants with phenylketonuria (PKU), dietary management is based on lowering and titrating phenylalanine (Phe) intake from breast milk or standard infant formula in combination with a Phe-free infant formula in order to maintain blood Phe levels within target range. Professionals use different methods to feed infants with PKU and our survey aimed to document practices across Europe. Methods: We sent a cross sectional, survey monkey (R) questionnaire to European health professionals working in IMD. It contained 31 open and multiple-choice questions. The results were analysed according to different geographical regions. Results: Ninety-five centres from 21 countries responded. Over 60% of centres commenced diet in infants by age 10 days, with 58% of centres implementing newborn screening by day 3 post birth. At diagnosis, infant hospital admission occurred in 61% of metabolic centres, mainly in Eastern, Western and Southern Europe. Breastfeeding fell sharply following diagnosis with only 30% of women still breast feeding at 6 months. 53% of centres gave pre-measured Phe-free infant formula before each breast feed and 23% alternated breast feeds with Phe-free infant formula. With standard infant formula feeds, measured amounts were followed by Phe-free infant formula to satiety in 37% of centres (n = 35/95), whereas 44% (n = 42/95) advised mixing both formulas together. Weaning commenced between 17 and 26 weeks in 85% centres, >= 26 weeks in 12% and < 17 weeks in 3%. Discussion: This is the largest European survey completed on PKU infant feeding practices. It is evident that practices varied widely across Europe, and the practicalities of infant feeding in PKU received little focus in the PKU European Guidelines (2017). There are few reports comparing different feeding techniques with blood Phe control, Phe fluctuations and growth. Controlled prospective studies are necessary to assess how different infant feeding practices may influence longer term feeding development., Vitaflo, We thank Vitaflo for supporting the publication cost of this paper.

Objective Isolated hypogonadotropic hypogonadism (IHH) is a rare disorder with pubertal delay, normal (normoosmic-IHH, nIHH) or defective sense of smell (Kallmann syndrome, KS). Other reproductive and non-reproductive anomalies might be present although information on their frequency are scanty, particularly according to the age of presentation. Design Observational cohort study carried out between January 2008 and June 2016 within a national network of academic or general hospitals. Methods We performed a detailed phenotyping of 503 IHH patients with: (1) manifestations of hypogonadism with low sex steroid hormone and low/normal gonadotropins; (2) absence of expansive hypothalamic/pituitary lesions or multiple pituitary hormone defects. Cohort was divided on IHH onset (PPO, pre-pubertal onset or AO, adult onset) and olfactory function: PPO-nIHH (n = 275), KS (n = 184), AO-nIHH (n = 36) and AO-doIHH (AO-IHH with defective olfaction, n = 8). Results 90% of patients were classified as PPO and 10% as AO. Typical midline and olfactory defects, bimanual synkinesis and familiarity for pubertal delay were also found among the AO-IHH. Mean age at diagnosis was significantly earlier and more frequently associated with congenital hypogonadism stigmata in patients with Kallmann’s syndrome (KS). Synkinesis, renal and male genital tract anomalies were enriched in KS. Overweight/obesity are significantly associated with AO-IHH rather than PPO-IHH. Conclusions Patients with KS are more prone to develop a severe and complex phenotype than nIHH. The presence of typical extra-gonadal defects and familiarity for PPO-IHH among the AO-IHH patients indicates a common predisposition with variable clinical expression. Overall, these findings improve the understanding of IHH and may have a positive impact on the management of patients and their families.

We develop the potential scattering of a spinor within the context of perturbation field theory. As an application, we reproduce, up to second order in the potential, the diffusion results for a potential barrier of quantum mechanics. An immediate consequence is a simple generalization to arbitrary potential forms, a feature not possible in quantum mechanics., Comment: 7 pages

The Megalithic Area of Saint-Martin-de-Corleans (Aosta, northern Italy) consists of anthropomorphic stelae dated to the Copper Age and the beginning of the Early Bronze Age. They were carved in different lithologies of varying provenance according to two successive artistic styles, ‘ancient’ and ‘evolved’. A minero-chemical and a petrographic investigation were carried out on 47 stelae and on reference samples collected from eight different outcrops, aiming to define the provenance of the stone materials. The variety of rocks used for the manufacture of the stelae reflects the geological complexity of the Aosta Valley. Most of the stelae examined were classified as foliated impure marbles, grey banded marbles (‘Bardiglio’), calcschists and metabasites belonging to the Combin Zone (Piedmont Nappe), which outcrops in close proximity to the Megalithic Area. Some stelae of the evolved group consisted of massive marbles with silicate-bearing layers, attributed to the Sion–Courmayeur Zone. Similar stone materials were reported for the stelae of the same age found at the archaeological area of Petit Chasseur (Sion, Switzerland). This is archaeometric confirmation of the archaeological affinity between the stelae occurring at the two prehistoric sites, supporting the hypothesis of cultural exchanges over the Grand St Bernard Pass since the Early Copper Age.

The renewed interest in searching for quaternionic deviations of standard (complex) quantum mechanics resulted, in the last years, in a better understanding of the quaternionic mathematical tools needed to solve quantum mechanical problems. In particular, a relevant progress has been achieved in solving eigenvalue problems and differential equations for quaternionic operators. The practical methods recently proposed to solve quaternionic and complex linear second-order differential equations with constant coefficients represent a fundamental starting point to discuss quaternionic potentials in quantum mechanics and study possible violations from complex theories. Nevertheless, only for a restricted class of real linear quaternionic differential operators (namely, symmetric operators) the solution of differential problems was given. In this paper, we study real linear quaternionic differential equations. The proposed resolution's method is based on the Jordan canonical form of (real linear) quaternionic matrices.

We discuss the existence in an arbitrary frame of a finite time for the transformation of an initial quantum state into another e.g. in a decay. This leads to the introduction of a timelapse $\tilde{\tau}$ in analogy with the lifetime of a particle. An argument based upon the Heisenberg uncertainty principle suggests the value of $\tilde{\tau}=1 / M_0$. Consequences for the exponential decay formula and the modifications that $\tilde{\tau}$ introduces into the Breit-Wigner mass formula are described., Comment: 5 pages [2 figs], ReV-TeX

Glutamine supplementation improves insulin sensitivity in critically ill patients, and prevents obesity in animals fed a high-fat diet. We hypothesized that glutamine supplementation favors weight loss in humans. Obese and overweight female patients (n=6) were enrolled in a pilot, cross-over study. After recording anthropometric (that is, body weight, waist circumference) and metabolic (that is, glycemia, insulinemia, homeostatic model of insulin resistance (HOMA-IR)) characteristics, patients were randomly assigned to 4-week supplementation with glutamine or isonitrogenous protein supplement (0.5 g/KgBW/day). During supplementation, patients did not change their dietary habits nor lifestyle. At the end, anthropometric and metabolic features were assessed, and after 2 weeks of washout, patients were switched to the other supplement for 4 weeks. Body weight and waist circumference significantly declined only after glutamine supplementation (85.0±10.4 Kg vs 82.2±10.1 Kg, and 102.7±2.0 cm vs 98.9±2.9 cm, respectively; P=0.01). Insulinemia and HOMA-IR declined by 20% after glutamine, but not significantly so. This pilot study shows that glutamine is safe and effective in favoring weight loss and possibly enhancing glucose metabolism.

We give a detailed analysis of the oscillation formula within the context of the wave packet formalism. Particular attention is made to insure flavor eigenstate creation in the physical cases (Delta p not equal 0). This requirement imposes non instantaneous particle creation in all frames. It is shown that the standard formula is not only exact when the mass wave packets have the same velocity, but it is a good approximation when minimal slippage occurs. For more general situations the oscillation formula contains additional arbitrary parameters, which allows for the unknown form of the wave packet envelope., 15 pages [8 figs], AMS-TeX

In this paper, a robust control algorithm, based on sliding modes techniques, designed for trajectory tracking is applied to a fixed-wing small Autonomous Aerial Vehicle (AAV). Based on a mathematical modeling, parameters identification, and aerodynamics of both the AAV fuselage and its mobile surfaces a full dynamical model is obtained, where the control is proven. However, for control design, simplified versions of the motion models are studied resulting in simplified independent controller for the roll, pitch and yaw trajectories. Due to the nature of such controller, time derivative of control variables are needed but not available. Numerical differentiators also based on sliding modes are used in order to estimate those derivatives. Simulation results are given to illustrate the performance of the proposed tracking controller under parametric and unmodeled dynamics.Copyright © 2011 by ASME

The mean-field Kuramoto model for synchronization of phase oscillators with an asymmetric bimodal frequency distribution is analyzed. Breaking the reflection symmetry facilitates oscillator synchronization to rotating wave phases. Numerical simulations support the results based of bifurcation theory and high-frequency calculations. In the latter case, the order parameter is a linear superposition of parameters corresponding to rotating and counterrotating phases., Revtex,4 pag,5 fig

The representation theory of the group U(1,q) is discussed in detail because of its possible application in a quaternion version of the Salam-Weinberg theory. As a consequence, from purely group theoretical arguments we demonstrate that the eigenvalues must be right-eigenvalues and that the only consistent scalar products are the complex ones. We also define an explicit quaternion tensor product which leads to a set of additional group representations for integer ``spin''., Comment: 28 pages, Latex, Dipartimento di Fisica, Universita di Lecce INFN-Sezione di Lecce

We report about recent results on Dirac wave packets in the treatment of neutrino flavor oscillation where the initial localization of a spinor state implies an interference between positive and negative energy components of mass-eigenstate wave packets. A satisfactory description of fermionic particles requires the use of the Dirac equation as evolution equation for the mass-eigenstates. In this context, a new flavor conversion formula can be obtained when the effects of chiral oscillation are taken into account. Our study leads to the conclusion that the fermionic nature of the particles, where chiral oscillations and the interference between positive and negative frequency components of mass-eigenstate wave packets are implicitly assumed, modifies the standard oscillation probability. Nevertheless, for ultra-relativistic particles and sharply peaked momentum distributions, we can analytically demonstrate that these modifications introduce correction factors proportional to (m12/p0) square which are practically un-detectable by any experimental analysis, 16 pages, 2 figures

While in general there is no one-to-one correspondence between complex and quaternion quantum mechanics (QQM), there exists at least one version of QQM in which a {\em partial} set of {\em translations} may be made. We define these translations and use the rules to obtain rapid quaternion counterparts (some of which are new) of standard quantum mechanical results., Comment: 15 pages, LaTeX, ULTH-93-38

We introduce an approximation scheme to perform an analytic study of the oscillation phenomena in a pedagogical and comprehensive way. By using Gaussian wave packets, we show that the oscillation is bounded by a time-dependent vanishing function which characterizes the slippage between the mass-eigenstate wave packets. We also demonstrate that the wave packet spreading represents a secondary effect which plays a significant role only in the non-relativistic limit. In our analysis, we note the presence of a new time-dependent phase and calculate how this additional term modifies the oscillating character of the flavor conversion formula. Finally, by considering Box and Sine wave packets we study how the choice of different functions to describe the particle localization changes the oscillation probability., 16 pages, 7 figures, AMS-TeX

The renewed interest in investigating quaternionic quantum mechanics, in particular tunneling effects, and the recent results on quaternionic differential operators motivate the study of resolution methods for quaternionic differential equations. In this paper, by using the real matrix representation of left/right acting quaternionic operators, we prove existence and uniqueness for quaternionic initial value problems, discuss the reduction of order for quaternionic homogeneous differential equations and extend to the non-commutative case the method of variation of parameters. We also show that the standard Wronskian cannot uniquely be extended to the quaternionic case. Nevertheless, the absolute value of the complex Wronskian admits a non-commutative extension for quaternionic functions of one real variable. Linear dependence and independence of solutions of homogeneous (right) H-linear differential equations is then related to this new functional. Our discussion is, for simplicity, presented for quaternionic second order differential equations. This involves no loss of generality. Definitions and results can be readily extended to the n-order case., 9 pages, AMS-TeX

We discuss the extension of a version of quaternion quantum mechanics to field theory and in particular to the simplest example, the free scalar field. A previous difficulty with the conservation of four-momentum for the "anomalous" bosonic particles is resolved.

We discuss the (right) eigenvalue equation for $\mathbb{H}$, $\mathbb{C}$ and $\mathbb{R}$ linear quaternionic operators. The possibility to introduce an isomorphism between these operators and real/complex matrices allows to translate the quaternionic problem into an {\em equivalent} real or complex counterpart. Interesting applications are found in solving differential equations within quaternionic formulations of quantum mechanics., Comment: 13 pages, AMS-TeX

Parastomal hernias are the most common cause of in patients surgically with stomy reoperation treated.Treatment of parastomal hernias has been faced through two kind of technics: the first one consisted in the translocation of colostomy, the second one was placing around the colostomic hole a marlex mesh which was inserted at muscular structure level. From January 1993 to May 1997 we treated 8 patients affected by paracolostomic hernia associated to laparocele. The laparocele was treated according Rives' technique with the prosthesis positioned in the properitoneal site. The parastomal hernia was treated with translocation of the colostomy in 3 cases; in the other patients a plastic surgery of the colostomic orifice was made using polypropylene little bandages in properitoneal site.In the postoperative period the complications concerned a single case of skin parcellar necrosis, that healed spontaneously with medications and a case of prolonged serous secretion the mean follow-up was 2 years from the wound.In our experience the use of marlex mesh may be effective in treatment of parastomal hernia only a patient treated with translocation of the stoma showed a recurrence of parastomal hernia. The positioning of the prosthesis at properitoneal level is subject to a lower incidence of recurrent parastomal hernia.

Obturator hernia is a rare cause of bowel obstruction which occurs mostly in elderly patients. Because symptoms are non-specific and hernia is rarely detectable on physical examination, preoperative diagnosis is difficult. Delay in diagnosis frequently leads to strangulation of the hernia and bowel resection so mortality remains high (25%). Although several techniques of obturator hernia repair have been described, surgical repair has not been standardized. We report a case of obturator hernia in a male patient previously operated on for inguinal hernia. It was discovered while operating for suspected recurrence of the right inguinal hernia. A new technical device which consists of the use of metal anchors allowed precise positioning of the mesh and avoids future dislocation.

Motivated by a quaternionic formulation of quantum mechanics, we discuss quaternionic and complex linear differential equations. We touch only a few aspects of the mathematical theory, namely the resolution of the second order differential equations with constant coefficients. We overcome the problems coming out from the loss of the fundamental theorem of the algebra for quaternions and propose a practical method to solve quaternionic and complex linear second order differential equations with constant coefficients. The resolution of the complex linear Schrodinger equation, in presence of quaternionic potentials, represents an interesting application of the mathematical material discussed in this paper., Comment: 25 pages, AMS-TeX

In order to obtain a consistent formulation of octonionic quantum mechanics (OQM), we introduce left-right barred operators. Such operators enable us to find the translation rules between octonionic numbers and $8\times 8$ real matrices (a translation is also given for $4\times 4$ complex matrices). The use of a complex geometry allows us to overcome the hermiticity problem and define an appropriate momentum operator within OQM. As an application of our results, we develop an octonionic relativistic free wave equation, linear in the derivatives. Even if the wave functions are only one-component we show that four independent solutions, corresponding to those of the Dirac equation, exist., 29 pages, RevTex

The authors report one rare case of primary adenocarcinoma of the vermiform appendix. The patient, an 83 year old female, presented with a non-pathognomonic symptomatology; diagnosis was made postoperatively. Surgery consisted of appendicectomy. The patient, due to her poor general condition, died three days after surgery for cardiocirculatory complications. In the light of the very rare case published in the literature, some diagnostic, anatomic-clinical, therapeutic and prognostic aspects of this rare tumor are discussed.

Authors report the postoperative complication rate in 52 patients who had undergone total thyroidectomy for cancer between 1984 to 1989. Total thyroidectomy has been performed in 9.8% of patients surgically treated for nodular thyroid pathology. Patients age average 49 years in a range 16-75; they were 49 women and 3 men. In 50% of cases we found papillary cancer, follicular in 40%, medullary 4% and anaplastic 6%. We shared postoperative complications in two mean groups: 1) aspecific complications as cardiocirculatory failure, respiratory failure, wound infections or collections, granulomas, keloids; 2) surgery related complications such as hypocalcemia, dysphagia, recurrent++ paralyses. The first group, we noticed just one case of respiratory mechanical failure due to severe tracheomalacia that required a temporary tracheostomy performed at the end of surgical procedure; we did not notice any death due to cardio-circulatory or respiratory failure, nor did we notice any postoperative hemorrhage; one patient presented a wound seroma, two patients presented granulomas due to subcutaneous stitches, and three developed papulous drug-induced erythema. The second group, eight patients developed a transient hypocalcemia beginning on the second postoperative day, without relevant tetanic crisis, well treated by calcium administration; only two of these patients developed permanent hypoparathyroidism. In 3 cases we had to perform exeresis of a laryngeal inferior nerve involved by the cancer, while in 5 more cases we noticed a transient monolateral paralysis that disappeared in 2 or 3 months. Three patients presented dysphagia before intervention and healed post-surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

The choice of the type of surgical treatment used in gastric cancer, in cases where it is possible to operate in relation to the extent of cancer, raises the question of whether the surgeon should perform a total exeresis of the organ, even in cases where the tumour is located in the 3rd distal of the stomach. A retrospective study was carried out on patients admitted to the Surgical Department of the University of Perugia between January 1963 and December 1988. Having rejected 123 cases because of incomplete data or insufficient follow-up, 1.140 cases were selected from a total of 1.263 patients. The sites of neoplasia were as follows: terminal esophagus: 1.76% of cases; cardia: 6.67%; fornix of the stomach: 9.37%; the body of the stomach and lesser curvature: 23.65%; body of the stomach (other portions): 10.07%; angulus: 3.63%; gastric antrum: 37.82%, pylorus: 4.45%; the remaining 2.58% showed a diffuse form involving two or more the above parts. The subdivision of the cases into stages, using the TNM classification, revealed the following groupings: 7.04% of patients were first observed at stage I, 20.70% at stage II, 42.04% at stage III and 30.20% at stage IV. From the above figures it is evident that radical surgical was indicated only in some of the patients observed. The prognostic factors examined in the comparative study of different tumour sites were: age, sex, macroscopic and histological tumour type, size, infiltration of neoplasia through gastric wall coat, lymph node and/or systemic diffusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastric cancer has always required surgical therapy since in the majority of cases at the moment of treatment symptoms are already at an advances stage. Over the past years many advances have been made in the early diagnosis of many forms of neoplasia, but the rate of progress has been much slower with regard to gastric cancer. Only the preventive and regular use of gastroscopy will allow the disease to be diagnosed at a non-advanced stage. The term early gastric cancer is used to describe a carcinoma which only infiltrates the mucosa, or the mucosa and submucosa, irrespective of lymph node or other metastases. The present study was based on a retrospective analysis of cases of stomach cancer observed in the Surgical Department of the University of Perugia from January 1963 to December 1988. A total of 1,263 patients were affected by cancer of the stomach during the above period. One hundred and twenty-three cases were not included because of incomplete data or insufficient follow-up. A total of 1,140 patients were therefore included in the study; of these only 99 cases were affected by early gastric cancer. Age, sex, earlier gastric diseases, life styles, familial occurrence of disease, and symptomatology were among the different parameters evaluated. In addition, the site of disease, diagnostic methods, pre- and post-operative staging, intramural diffusion of the disease and surgical treatment were taken into account. In older cases the 5-year survival rate was calculated, whereas in more recent cases statistical methods, based on accumulated data, were used to estimate survival rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Aim of our present work was to investigate a new method to study the three-dimensional arrangement, the length and the diameter of the different parts of the renal tubules. The ureter was cannulated after blocking the urinary flow with a binding of the ureter itself at its intermediate third, and injected in it against flow a synthetic resin (Mercox) normally used for vascular corrosion casts. It was demonstrated that the binding maintained only for 24 hours is adequate for morphological studies of the urinary tracts from papillar ducts until the Henle's loop. On the contrary the binding maintained for 7 days induced marked changes in the tubular architecture similar to the first anatomo-pathological changes of the nephrosclerosis following a chronic obstructive nephropathy.

The authors describe a new exper imental model for lymphedema of rabbit ear. The method proved to be reliable and easily reproducible. The dilatation of lymph vessels after ex perimental provocation of lymphe dema permits study of the physio pathologic basis of lymphovenous shunts created by means of micro surgery and proves to be helpful for the microsurgeon's practice.