Pediatric admissions to emergency departments of North-Western Italy during COVID-19 pandemic: A retrospective observational study.

Background: COVID-19 pandemic caused huge decrease of pediatric admissions to Emergency Department (ED), arising concerns about possible delays in diagnosis and treatment of severe disorders.

Methods: Impact of COVID-19 on Pediatric Emergency Room (ICOPER) was a retrospective multicentre observational study including 23 Italian EDs.All the children <18 years admitted, between March 9th and May 3rd 2020 stratified by age, priority code, cause of admission and outcome have been included and compared to those admitted in the same period of 2019.

Late and unusual onset of congenital duodenal obstruction due to combination lesion.

Duodenal obstruction is one of the most common congenital anomalies. Both intrinsic (atresia, web and stenosis) or extrinsic lesions (malrotation, peritoneal bands, intestinal duplication, anterior portal vein and annular pancreas) may be involved. It usually presents within the first week of life with vomiting.

Mutations in TAZ/WWTR1, a co-activator of NKX2.1 and PAX8 are not a frequent cause of thyroid dysgenesis.

Aim: In 80-85% of cases, congenital hypothyroidism is associated with thyroid dysgenesis (TD), but only in a small percentage of cases mutations in thyroid transcription factors (NKX2.1, PAX8, FOXE1, and NKX2.5) have been associated with the disease.

Speckle velocimetry by means of holographic time-integrative correlation.

We develop the theory of the speckle velocimeter that is based on use of a photorefractive real-time hologram in four-wave mixing as a time-integrative correlator. The theory of the speckle velocimeter has been developed for the time correlation between the far-field spectrum of light scattered from the diffuser and the reference wave that is Doppler shifted. Our theoretical derivation shows that it is possible to extract the velocity with minor processing of the output correlation.

Wiener-like correlation filters.

We introduce a new, to our knowledge, design for a Wiener-like correlation filter, which consists of cascading a phase-only filter (POF) with a photorefractive Wiener-like filter. Its performance is compared with that of the POF and the Wiener correlation filter (WCF). Correlation results show that for intermediate and higher levels of noise this correlation filter has a peak-to-noise ratio that is larger than that of either the POF or the WCF while still preserving a correlation peak that is almost as high as that of the POF.

Synthetic aperture radar image correlation by use of preprocessing for enhancement of scattering centers.

We demonstrate that a significant improvement can be obtained in the recognition of complicated synthetic aperture radar images taken from the Moving and Stationary Target Acquisitions and Recognition database. These images typically have a low number of scattering centers and high noise. We first preprocess the images and the templates formed from them so that their scattering centers are enhanced.

Phase-restricted heterogeneous correlation.

We introduce a new phase-restricted algorithm for producing a heterogeneous correlation filter that permits new in-class members to be added without changing the phase of the filter. This heterogeneous correlation filter uses amplitude modulation both to enhance in-class cross correlations and to suppress selected out-of-class correlations. This new algorithm should substantially improve the performance of existing class-associative correlators and improve their operation.

Homodyne and heterodyne imaging through a scattering medium.

We introduce a novel two-dimensional (2D) homodyne and heterodyne technique for imaging objects through or embedded in a scattering medium. Our imaging approach is based on heterodyning of light with different Doppler broadenings that is scattered from objects of two different textures or from an opaque object and a textured scattering medium. We report on the initial demonstration of pulling signals out of noise for an object hidden behind a scattering medium.

Familial PAX8 small deletion (c.989_992delACCC) associated with extreme phenotype variability.

The PAX8 gene, mapped on 2q12-q14, encodes for a transcription factor involved in thyroid cell proliferation and differentiation. Five mutations in PAX8 have been so far described in both sporadic and rare familial forms of thyroid dysgenesis with proposed autosomal dominant inheritance, all associated with thyroid hypoplasia and/or dysfunction. Fifty-four subjects with congenital hypothyroidism detected during neonatal screening and associated with an ultrasound or scintiscan picture of thyroid dysgenesis were investigated for PAX8 mutations.

In congenital hypothyroidism bone maturation at birth may be a predictive factor of psychomotor development during the first Year of life irrespective of other variables related to treatment.

Objective: To evaluate in a cohort of infants with congenital hypothyroidism (CH): (a) the frequency of bone maturation (BM) retardation at birth and (b) whether BM delay at birth may be considered as a tool to make a prognosis of psychomotor status at the age of 1 Year, irrespective of other variables related to treatment.

Design: BM at birth, CH severity and developmental quotient (DQ) at the age of 1 Year were retrospectively evaluated in 192 CH infants selected by the following inclusion criteria: (a) gestation age ranging between 38 and 42 weeks; (b) onset of therapy within the first Month of life; (c) initial thyroxine (l-T(4)) dosage ranging from 10 to 12 microg/kg/day; (d) normalization of serum thyrotropin (TSH) levels before the age of 3 Months; (e) Monthly adjustments of l-T(4) dose during the first Year of life with serum TSH levels ranging from 0.5 to 4 mIU/l; (f) no major diseases and/or physical handicaps associated with CH; (g) availability of both thyroid scanning and knee X-rays at the time of treatment initiation; (h) availability of DQ assessment at an average age of 12 Months.

Effect of Lactobacillus GG and breast-feeding in the prevention of rotavirus nosocomial infection.

Background: Rotavirus is one of the leading etiologic agents of nosocomial infections among children. The development of preventive measures is therefore important. The efficacy of GG in the treatment of rotavirus infection has been reported in literature, but there is only one recent study about its effectiveness in prevention of infection.

Incidence of nosocomial rotavirus infections, symptomatic and asymptomatic, in breast-fed and non-breast-fed infants.

Rotavirus is one of the most important aetiological agents of nosocomial infections in childhood. We studied the incidence of nosocomial rotavirus infections in 420 patients (age range 1-18 months) consecutively admitted from 1 December 1999 to 31 May 2000 to the infant ward of the Department of Paediatrics, University of Turin. We also evaluated the protective effect of breast feeding.

Analysis of spatial light modulator contrast ratios and optical correlation.

We have performed a general analysis of optical correlators with spatal light modulators (SLM's) whose primary defect is a finite contrast ratio (CR). Our mathematical analysis identifies three noise terms that appear in addition to the correlation term. The filter SLM contains either a phase-only filter (POF) or a binary-phase-only filter (BPOF).

Nearly optimal correlations for shift-invariant associative memories.

The optical implementation of the Hopfield algorithm in shift-invariant holographic associative memories is based on the use of correlators with matched filters. However, it is well known that such correlators have poor discrimination. We propose nearly optimal correlation designs for associative memories based on correlation filters that have maximum discrimination ability.

Nonlinear techniques in optical pattern recognition: introduction by the feature editors.

This feature of Applied Optics is dedicated to research in optical pattern-recognition techniques that utilize nonlinear devices and algorithms. Nonlinearities are employed in a variety of ways in optical pattern recognition and play an important role in both hardware implementation and software development for optical pattern-recognition systems.

General treatment of spatial light modulator dead-zone effects on optical correlation. II. Mathematical analysis.

We present a general analytical treatment of optical correlation in correlators that use pixellated spatial light modulators with transmissive (or reflective) dead zones in both the input and filter planes. The active areas of the pixels modulate the light intensity while the dead zones transmit (or reflect) all of the light. Our model can predict the changes in the correlation peak and the signal-to-noise ratio with changes in dead zones, calculated in Part I [Appl.

General treatment of spatial light modulator dead-zone effects on optical correlation. I. Computer simulations.

In Part I we present an approximate mathematical analysis and exact computer simulations for optical correlation in correlators having pixellated spatial light modulators with transmissive (or reflective) dead zones in both the input and filter planes. We show that the correlation amplitude consists of four terms: a true correlation plus three different types of noise terms originating from the transmissive dead zones in both spatial light modulators; we describe the role that each of these terms plays in the correlation process. We calculate peak intensity, signal-to-noise ratio, and energy throughput efficiency as a function of dead-zone area in both spatial light modulators using either phase-only or matched filters.

Effects of spatial light modulator opaque dead zones on optical correlation.

Each pixel of a spatial light modulator (SLM) consists of a phase- or amplitude-modulating area (the active zone) within an inactive area (the dead zone). Here we study optical correlators that contain input and filter SLM's whose dead zones are opaque. Computer simulations and analytical calculations are carried out for these correlators when a phase-only, a binary phase-only, or a classical matched filter is written on the filter SLM.

Effects of quadratic phase distortion on correlator performance.

The deformable mirror spatial light modulator (SLM) has an inherent distortion characteristic that can be approximated as a square-law transfer function. We examine the result of this distortion when this SLM is used in an optical correlator.

[Growth velocity in thalassemic children receiving different protocols of chelating therapy].

The aim of this study was to compare growth velocity in thalassemic children using two different treatment protocols. Thalassemic children were initially treated with high daily doses of desferrioxamine, obtaining a good rate of initial growth which then unexpectedly slowed down later. The introduction of a new treatment protocol reducing both the dose and frequency with which the drug was administered provoked a significant increase in the rate of growth greater than that observed in the group treated using the previous protocol.

Signal-dependent phase distortion in optical correlators.

We examine the effect of phase distortion inherent in a spatial light modulator on the performance of an optical correlator. We examine such areas as input plane distortion, input and Fourier plane distortion, effect of phase mismatch between these planes, and the effect of additive white noise. When large distortions are present and the proper compensation is incorporated into the filter, we find a significant enhancement in performance in that the correlation response converges to a function and the SNR increases significantly.