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Transition-metal dichalcogenides PtTe2, PdTe2, and NiTe2 deserve particular attention, due to the presence of type-II Dirac fermions. As a matter of fact, tilted Dirac cones afford a suitable platform for optoelectronics of dissipation-less carrier-transport, favored by their ultrahigh carrier mobility, and large nonsaturating magnetoresistance. Herein, it is shown that PtTe2, PdTe2, and NiTe2 display high-speed terahertz (THz) detection capability at room temperature, which originates from their peculiar band structure with topologically protected electronic states. Furthermore, photodetectors based on their heterostructures are able to suppress dark current with high-performance detection of THz light. Furthermore, these crystals are stable in air and they can be easily exfoliated in nanosheets by liquid-phase exfoliation, due to the weak interlayer van der Waals bonds. The obtained results clearly establish that the type-II Dirac semimetals based on transition-metal ditellurides have immense research potential for addressing application-oriented issues for remote sensing and telecommunications. © 2021 The Authors. physica status solidi (RRL) Rapid Research Letters published by Wiley-VCH GmbH.

Recently, germanium selenide (GeSe) has emerged as a promising van der Waals semiconductor for photovoltaics, solar light harvesting, and water photoelectrolysis cells. Contrary to previous reports claiming perfect ambient stability based on experiments with techniques without surface sensitivity, here, by means of surface-science investigations and density functional theory, it is demonstrated that actually both: i) the surface of bulk crystals; and ii) atomically thin flakes of GeSe are prone to oxidation, with the formation of self-assembled germanium-oxide skin with sub-nanometric thickness. Surface oxidation leads to the decrease of the bandgap of stoichiometric GeSe and GeSe1−x, while bandgap energy increases upon surface oxidation of Ge1−xSe. Remarkably, the formation of a surface oxide skin on GeSe crystals plays a key role in the physicochemical mechanisms ruling photoelectrocatalysis: the underlying van der Waals semiconductor provides electron–hole pairs, while the germanium-oxide skin formed upon oxidation affords the active sites for catalytic reactions. The self-assembled germanium-oxide/germanium-selenide heterostructure with different bandgaps enables the activation of photocatalytic processes by absorption of light of different wavelengths, with inherently superior activity. Finally, it is discovered that, depending on the specific solvent-GeSe interaction, the liquid phase exfoliation of bulk crystals can induce the formation of Se nanowires. © 2021 The Authors. Advanced Functional Materials published by Wiley-VCH GmbH

The study of chemical processes on solid surfaces is a powerful tool to discover novel physicochemical concepts with direct implications for processes based on chemical reactions at surfaces, largely exploited by industry. Recent upgrades of experimental tools and computational capabilities, as well as the advent of two-dimensional materials, have opened new opportunities and challenges for surface science. In this Perspective, we highlight recent advances in application fields strictly connected to novel concepts emerging in surface science. Specifically, we show for selected case-study examples that surface oxidation can be unexpectedly beneficial for improving the efficiency in electrocatalysis (the hydrogen evolution reaction and oxygen evolution reaction) and photocatalysis, as well as in gas sensing. Moreover, we discuss the adsorption-assisted mechanism in membrane distillation for seawater desalination, as well as the use of surface-science tools in the study of Li-ion batteries. In all these applications, surface-science methodologies (both experimental and theoretical) have unveiled new physicochemical processes, whose efficiency can be further tuned by controlling surface phenomena, thus paving the way for a new era for the investigation of surfaces and interfaces of nanomaterials. In addition, we discuss the role of surface scientists in contemporary condensed matter physics, taking as case-study examples specific controversial debates concerning unexpected phenomena emerging in nanosheets of layered materials, solved by adopting a surface-science approach. © the Owner Societies 2020.

Tin diselenide (SnSe2) is a van der Waals semiconductor, which spontaneously forms a subnanometric SnO2 skin once exposed to air. Here, by means of surface-science spectroscopies and density functional theory, we have investigated the charge redistribution at the SnO2-SnSe2 heterojunction in both oxidative and humid environments. Explicitly, we find that the work function of the pristine SnSe2 surface increases by 0.23 and 0.40 eV upon exposure to O2 and air, respectively, with a charge transfer reaching 0.56 e-/SnO2 between the underlying SnSe2 and the SnO2 skin. Remarkably, both pristine SnSe2 and defective SnSe2 display chemical inertness toward water, in contrast to other metal chalcogenides. Conversely, the SnO2-SnSe2 interface formed upon surface oxidation is highly reactive toward water, with subsequent implications for SnSe2-based devices working in ambient humidity, including chemical sensors. Our findings also imply that recent reports on humidity sensing with SnSe2 should be reinterpreted, considering the pivotal role of the oxide skin in the interaction with water molecules. ©

Resource management of a natural mineral water system, with high socio-economic interest, requires a multidisciplinary approach in order to ensure the sustainability of the exploitation. The aim of the study is the definition of the hydrogeological conceptual model of "Ferrarelle" sparkling mineral water system (FMS) in Riardo Plain (RP) and the calculation of the hydrological budget of the recharge area through the definition of groundwater flow system and the identification of the geometry, extension and spatial relationships between carbonate and volcanic formations. RP is located east of the Roccamonfina Volcano, being enclosed south, east and north by Mesozoic carbonate ridge. The bedrock in RP is mostly composed of Mesozoic carbonate rock with overlying Pleistocene volcanic, volcaniclastic and alluvial deposits. Structural setting is made up mostly of tensional NE-SW and NW-SE trending fault systems affecting carbonate rocks. Moreover deep faults and fractures systems are the way for the CO2 rising up. Over the last three years several hydrogeological surveys were carried out by "Roma Tre University". Groundwater levels and chemical-physical parameters were measured in more than 230 wells. Discharge rate of about 50 springs and 33 stream were measured during the surveys. The hydrogeological data were integrated with the chemical analyses of 53 water samples. A database was created in order to integrate bibliographic to experimental data, and then a geodatabase was implemented in GIS. The results show a dynamic watershed within RP that separates two hydrogeological basins: Savone basin draining toward SW and Rio delle Starze basin draining toward NE. In the first basin the piezometric levels are similar both in deep (withdrawing from the carbonate aquifer) and in shallow wells (draining volcaniclastic aquifer). The results force to think that volcaniclastic and carbonate-rock aquifer are hydrologically connected at the least at Savone basin. Hydrological relati

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Purpose Neural tube defects (NTDs) occur in 1:1000 births. The etiology is complex, with the influence of environmental and genetic factors. Environmental factors, such as folate deficiency, diabetes, or hypoxia strongly contribute to the occurrence of NTD. Also, there is a strong genetic contribution to NTD, as highlighted by the number of genes so far identified in several different developmental pathways usually altered in NTD. Each gene identified so far accounts for a small percentage of all NTD cases, indicating a very high heterogeneity. Methods Exome sequencing was performed in seven sporadic patients with severe mielomeningocele. Novel coding variants shared by two or more patients were selected for further analysis. Results We identified in two unrelated patients two different variants in TNIP1, a gene not previously involved in NTD whose main role is downregulation of the NF-kB pathway. One variant, c.1089T>G (p.Phe363Leu), is de novo, whereas the c.1781C>T (p.Pro594Leu) is absent in the mother, but could not be tested in the father, as he was unavailable. The latter variant is a very rare variant in the ExAC database. Conclusions These findings suggest that TNIP1 is a new potential predisposing gene to spina bifida (SB) and its pathway needs to be investigated in human NTD in order to confirm its role and to plan appropriate counseling to families.

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Analytical assessment of bone serum markers in patients suffering from spina bifida

Neurotrophic factors, such as Nerve Growth Factor (NGF), play a key role in the stimulation of sprouting, synaptic plasticity, and reorganization after spinal cord damage.

Prospective study.

Jacquet erosive diaper dermatitis

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Prospective study on local treatment of pressure sores using calcium alginate and foam dressings in spina bifida patients.

BACKGROUND: Fetal hydronephrosis is the most common anomaly detected on antenatal ultrasound examination, affecting 1-5% pregnancies. AIM: A new management in mild antenatal renal pelvis dilatation (ARPD), using a technique based on both morphological and dynamical evaluation. MATERIALS AND METHODS: Prospective study conducted during a 36-months period in 180 consecutive newborns referred as having mild ARPD. Examinations consisted in a morphological ultra-sound (US) scan evaluating antero-posterior diameter, renal parenchyma, ureteral evidence and pelvis morphology and, subsequently, a dynamic evaluation to analyze any change of the urinary tract during bladder voiding. All children were evaluated both at 3rd day and 1 month after birth. They were divided among those with negative examinations and those with at least one positive scan, trying to discriminate within the latter, children suspected for transient pyelectasis from those suspected for organic pathology. RESULTS: 108 patients had normal US findings both at birth and at 1 month. The remaining 72 babies had at least one abnormal US examination: 54 were suspected for transient pyelectasis, while 18 suspected for organic pathology. At the end of the study, 61 babies (33.9%) had final diagnosis of transient pyelectasis and 11 cases (6.1%) of organic pathology. At one month the dynamic pattern of US findings had the highest negative predictive value, while renal parenchyma evaluation has the highest accuracy. CONCLUSIONS: a dynamic US approach allowed to better select among infants suspected for transient pyelectasis from those suspected for organic pathology, avoiding unnecessary and invasive examinations in healthy babies.

Fetal hydronephrosis is the most common anomaly detected on antenatal ultrasound examination, affecting 1-5% pregnancies.

PURPOSE: The aim of the present study is to establish if the vestibular evoked myogenic potentials (VEMPs) could be used as a clinical test for the evaluation of vestibular function in children affected by myelomeningocele (MMC). MATERIALS AND METHODS: Fifteen children, aged between 3 and 17 years, who had been affected by MMC were investigated. Data obtained from these children were compared with normal data from healthy children of the same age. Electromyographic activity of sternocleidomastoid muscle was recorded, while children were laid supine and asked to raise their head off the bed in order to activate their neck flexors bilaterally. The saccular receptors were acoustically stimulated with a logon of 500 Hz at an intensity of 130 dB peSPL presented monaurally through earphones. In each recording, we analyzed latencies and amplitudes of the p13-and n23 waves and the amplitude ratio between the two ears. RESULTS: VEMPs were detected to be normal in 13 patients. In particular, the mean p13 and mean n23 latencies were 15.7 (±1.4) and 21.7 (±1.1) ms, respectively; the mean amplitude value was 84.7 (±36.6), while the mean amplitude ratio was 17.4 (±12). A comparison of latencies and amplitude ratios between the children and healthy control group did not reveal any significant difference. On the contrary, a comparison of amplitude values between the two groups showed significant differences. CONCLUSION: In conclusion, vestibulocollic reflex is normal in patients affected by MMC, and VEMPs could represent a valid and noninvasive technique eligible to investigate the vestibular functions in these children.

Interventions directed to the recognition of abnormal bone mineral density, bone mineral content, and body composition in the pediatric age require the definition of factors influencing bone mass acquisition during growth. We have evaluated in a cross-sectional manner by dualenergy X-ray absorptiometry the impact of sex, age, puberty, and physical activity on total body areal bone mineral density, regional (lumbar and femoral) bone mineral densities, bone mineral content, and body composition (fat mass and lean mass) in a cohort of 359 healthy Italian children aged 3-14 years and investigated their specific contribution to bone mass accrual. Statistical multiple regression analysis was performed dividing the population in pre- and post-pubertal groups. Bone mineral density at the lumbar spine has resulted equally distributed in both sexes before puberty while has resulted higher at the femoral necks in males at whatever age. A significant effect on bone mass acquisition was exerted by male sex and lean mass. In the areas where the cortical bone is prevalent, males of the pre-pubertal group have presented the highest values; in the areas where the cancellous bone is prevalent, both sexes were equivalent until the age of 9 years, but after this age, females have presented higher increases, probably related to the inferior dimensional development of lumbar vertebrae. Conclusively, male sex and lean mass seem to represent independent predictors of bone mass accrual in the cortical bone of the examined children, while female sex and pubertal maturation are independent predictors of bone mass accrual in the trabecular bone. © Springer-Verlag 2011.

Early discharge of healthy late preterm and full term newborn infants has become common practice because of the current social and economic necessities. Severe jaundice, and even kernicterus, has developed in some term infants discharged early. This study was designed to elaborate a percentile-based hour specific total serum bilirubin (TSB) nomogram and to assess its ability to predict the absence of risk for subsequent non physiologic severe hyperbilirubinaemia before discharge.

Early discharge of healthy late preterm and full term newborn infants has become common practice because of the current social and economic necessities. Severe jaundice, and even kernicterus, has developed in some term infants discharged early. This study was designed to elaborate a percentile-based hour specific total serum bilirubin (TSB) nomogram and to assess its ability to predict the absence of risk for subsequent non physiologic severe hyperbilirubinaemia before discharge.

PURPOSE: The aim of the present study is to establish if the vestibular evoked myogenic potentials (VEMPs) could be used as a clinical test for the evaluation of vestibular function in children affected by myelomeningocele (MMC). MATERIALS AND METHODS: Fifteen children, aged between 3 and 17 years, who had been affected by MMC were investigated. Data obtained from these children were compared with normal data from healthy children of the same age. Electromyographic activity of sternocleidomastoid muscle was recorded, while children were laid supine and asked to raise their head off the bed in order to activate their neck flexors bilaterally. The saccular receptors were acoustically stimulated with a logon of 500 Hz at an intensity of 130 dB peSPL presented monaurally through earphones. In each recording, we analyzed latencies and amplitudes of the p13-and n23 waves and the amplitude ratio between the two ears. RESULTS: VEMPs were detected to be normal in 13 patients. In particular, the mean p13 and mean n23 latencies were 15.7 (±1.4) and 21.7 (±1.1) ms, respectively; the mean amplitude value was 84.7 (±36.6), while the mean amplitude ratio was 17.4 (±12). A comparison of latencies and amplitude ratios between the children and healthy control group did not reveal any significant difference. On the contrary, a comparison of amplitude values between the two groups showed significant differences. CONCLUSION: In conclusion, vestibulocollic reflex is normal in patients affected by MMC, and VEMPs could represent a valid and noninvasive technique eligible to investigate the vestibular functions in these children.

BACKGROUND: Hypertensive disorders in pregnancy account for increased perinatal morbidity and mortality when compared to uneventful gestations. AIMS: To analyze perinatal outcome of pregnancies complicated by different kinds of hypertension to uncomplicated pregnancies in a series of Italian women and to compare our data with series from other countries. STUDY DESIGN: The sample was divided into four groups of hypertensive women: chronic hypertension (CH), gestational hypertension (GH), preeclampsia (PE), and chronic hypertension complicated by preeclampsia (CHPE). One thousand normal pregnancies served as controls. SUBJECTS: Neonatal features of the offspring of 965 Italian women with hypertension in pregnancy were evaluated. MEASURES: Gestational age, birthweight and the rate of small for gestational age were the outcomes. Perinatal asphyxia and mortality were also assessed. RESULTS: Gestational age, the mean of birth weight and birth percentile were significantly lower in all groups with hypertensive complications when compared with controls. The rate of very early preterm delivery (<32weeks) was 7.8% in CH, 5.9% in GH, 21.2% in PE and 37.2% in CHPE while it was to 1.2% in the control group. The rate of SGA was globally 16.2% in CH, 22.8% in GH, 50.7% in PE, 37.2% in CHPE and 5% in controls. The rate of SGA in PE was much higher than reported in series from other countries. CONCLUSION: Comparing our data with those reported from other countries, it is evident that the rate of fetal growth restriction in PE we found in our center, is significantly higher even in the presence of a global lower incidence of PE.