Pressure and temperature dependentab-initioquasi-harmonic thermoelastic properties of tungsten.

We present theab-initiotemperature and pressure dependent thermoelastic properties of body-centered cubic tungsten. The temperature dependent quasi-harmonic elastic constants (ECs) are computed at several reference volumes including both the phonon and the electronic excitations contribution to the free energy and interpolated at different temperatures and pressures. Good agreement with the experimental ECs on a single crystal at ambient pressure is found. The pressure and temperature dependence of the shear sound velocity measured on polycrystalline tungsten by Qiet alis also in agreement with theory. Some discrepancies are found instead for the compressional velocity at high temperature and this is attributed to the temperature derivative of the bulk modulus, higher in theory than in experiment. These conclusions are reached both by PBE and by PBEsol functionals. The two give elastic properties with a similar pressure and temperature dependence although the latter is closer to experiment at 0 K.

The Influence of Early Nutrition on Neurodevelopmental Outcomes in Preterm Infants.

Premature infants, given their limited reserves, heightened energy requirements, and susceptibility to nutritional deficits, require specialized care. AIM: To examine the complex interplay between nutrition and neurodevelopment in premature infants, underscoring the critical need for tailored nutritional approaches to support optimal brain growth and function. DATA SOURCES: PubMed and MeSH and keywords: preterm, early nutrition, macronutrients, micronutrients, human milk, human milk oligosaccharides, probiotics AND neurodevelopment or neurodevelopment outcomes. Recent articles were selected according to the authors' judgment of their relevance. Specific nutrients, including macro (amino acids, glucose, and lipids) and micronutrients, play an important role in promoting neurodevelopment. Early and aggressive nutrition has shown promise, as has recognizing glucose as the primary energy source for the developing brain. Long-chain polyunsaturated fatty acids, such as DHA, contribute to brain maturation, while the benefits of human milk, human milk oligosaccharides, and probiotics on neurodevelopment via the gut-brain axis are explored. This intricate interplay between the gut microbiota and the central nervous system highlights human milk oligosaccharides' role in early brain maturation. CONCLUSIONS: Individualized nutritional approaches and comprehensive nutrient strategies are paramount to enhancing neurodevelopment in premature infants, underscoring human milk's potential as the gold standard of nutrition for preterm infants.

Primary closure of a sternal cleft in the neonatal period.

Sternal cleft is a rare malformation of the midline fusion of the sternal bars; the most common form is the superior partial defect. Surgical correction with primary closure is the gold standard. It is recommended that the procedure be performed before 3 months of age because of the greater compliance and maximal flexibility of the thoracic wall.  These features ensure a safer repair with a low risk of complications and allow for a less extensive procedure that does not require the use of additional techniques. A midline incision is performed in the anterior thoracic wall, and the major pectoralis flaps are raised. The main surgical goal is to change the remaining sternum from a U to a V shape. Transfixing interrupted sutures are placed in the cartilaginous borders for midline closure. Hemodynamics and ventilation are monitored at this time. Closure is performed by layers.

Autopsy in a Neonatal Intensive Care Unit: pathological and clinical agreement

Abstract Objectives To evaluate neonatal autopsy rates at a tertiary hospital in southern Brazil ascertain the level of agreement between premortem and postmortem diagnosis. Methods The authors reviewed all neonatal autopsies performed over a 10-year period and described the percentage of neonates who died and underwent autopsy. The authors tested for agreement between autopsy findings and the cause of death as defined by the neonatologist. Agreement between clinical diagnosis and autopsy findings was classified using the modified Goldman criteria. Additional findings at autopsy were grouped by organ system. Linear regression and multiple comparisons were used for statistical analyses. Results During the study period, 382 neonates died at the Neonatal Intensive Care Unit (NICU). Consent to perform an autopsy was obtained for 73 (19.1%). The complete agreement between autopsy findings and the neonatologist's premortem diagnosis was found in 48 patients (65.8%). Additional findings were obtained at autopsy in 25 cases (34.2%). In 5 cases (6.9%), the autopsy findings contributed to subsequent genetic counseling. Seven autopsies (9.6%) revealed a diagnosis that would have changed patient management if established premortem. The autopsy rate increased by an average of 1.87% each year. Conclusion Despite a high level of agreement between clinical diagnosis and pathological findings, autopsies provided relevant data regarding the cause of death, providing additional clinical information to neonatologists and allowing genetic counseling of family members.

Finite-temperature atomic relaxations: Effect on the temperature-dependent C44 elastic constants of Si and BAs.

The effect of atomic relaxations on the temperature-dependent elastic constants (TDECs) is usually taken into account at zero temperature by the minimization of the total energy at each strain. In this paper, we investigate the order of magnitude of this approximation on a paradigmatic example: the C44 elastic constant of diamond and zincblende materials. We estimate the effect of finite-temperature atomic relaxations within the quasi-harmonic approximation by computing ab initio the internal strain tensor from the second derivatives of the Helmholtz free-energy with respect to strain and atomic displacements. We apply our approach to Si and BAs and find a visible difference between the softening of the TDECs computed with the zero-temperature and finite-temperature atomic relaxations. In Si, the softening of C44 passes from 8.6% to 4.5%, between T = 0 K and T = 1200 K. In BAs, it passes from 8% to 7%, in the same range of temperatures. Finally, from the computed elastic constant corrections, we derive the temperature-dependent Kleinman parameter, which is usually measured in experiments.

Autopsy in a Neonatal Intensive Care Unit: pathological and clinical agreement.

OBJECTIVES: To evaluate neonatal autopsy rates at a tertiary hospital in southern Brazil ascertain the level of agreement between premortem and postmortem diagnosis. METHODS: The authors reviewed all neonatal autopsies performed over a 10-year period and described the percentage of neonates who died and underwent autopsy. The authors tested for agreement between autopsy findings and the cause of death as defined by the neonatologist. Agreement between clinical diagnosis and autopsy findings was classified using the modified Goldman criteria. Additional findings at autopsy were grouped by organ system. Linear regression and multiple comparisons were used for statistical analyses. RESULTS: During the study period, 382 neonates died at the Neonatal Intensive Care Unit (NICU). Consent to perform an autopsy was obtained for 73 (19.1%). The complete agreement between autopsy findings and the neonatologist's premortem diagnosis was found in 48 patients (65.8%). Additional findings were obtained at autopsy in 25 cases (34.2%). In 5 cases (6.9%), the autopsy findings contributed to subsequent genetic counseling. Seven autopsies (9.6%) revealed a diagnosis that would have changed patient management if established premortem. The autopsy rate increased by an average of 1.87% each year. CONCLUSION: Despite a high level of agreement between clinical diagnosis and pathological findings, autopsies provided relevant data regarding the cause of death, providing additional clinical information to neonatologists and allowing genetic counseling of family members.

Intra-breath oscillometry for the evaluation of lung function in children and adolescents with a history of preterm birth.

OBJECTIVE: To assess respiratory system impedance (Zrs) and spirometric parameters in children and adolescents with and without a history of preterm birth. METHODS: We evaluated a sample of 51 subjects between 11 and 14 years of age: 35 who had a history of preterm birth (preterm group) and 16 who had been born at term (full-term group). Lung function was measured by spirometry, spectral oscillometry, and intra-breath oscillometry. RESULTS: Neither spirometry nor spectral oscillometry revealed any statistically significant differences between the preterm and full-term groups. However, intra-breath oscillometry demonstrated significant differences between the two groups in terms of the change in resistance, reactance at end-inspiration, and the change in reactance (p < 0.05 for all). CONCLUSIONS: Our findings suggest that abnormalities in Zrs persist in children and adolescents with a history of preterm birth and that intra-breath oscillometry is more sensitive than is spectral oscillometry. Larger studies are needed in order to validate these findings and to explore the impact that birth weight and gestational age at birth have on Zrs later in life.

Meconium microbiota predicts clinical early-onset neonatal sepsis in preterm neonates.

BACKGROUND: Early-onset neonatal sepsis (EONS) remains one of the leading causes of morbidity and mortality related to premature birth, and its diagnosis remains difficult. Our goal was to evaluate the intestinal microbiota of the first meconium of preterm newborns and ascertain whether it is associated with clinical EONS. METHODS: In a controlled, prospective cohort study, samples of the first meconium of premature infants with a gestational age (GA) ≤32 weeks was obtained at Hospital de Clínicas de Porto Alegre and DNA was isolated from the samples. 16S rDNA based microbiota composition of preterm infants with a clinical diagnosis of EONS was compared to that of a control group. RESULTS: 40 (48%) premature infants with clinical diagnosis of EONS and 44 (52%) without EONS were included in the analysis. The most abundant phylum detected in both groups, Proteobacteria, was more prevalent in the sepsis group (p = .034). 14% of variance among bacterial communities (p = .001) correlated with EONS. The genera most strongly associated with EONS were Paenibacillus, Caulobacter, Dialister, Akkermansia, Phenylobacterium, Propionibacterium, Ruminococcus, Bradyrhizobium, and Alloprevotella. A single genus, Flavobacterium, was most strongly associated with the control group. CONCLUSION: These findings suggest that the first-meconium microbiota is different in preterm neonates with and without clinical EONS.

Percutaneous glue embolization of arteriovenous fistula of in situ saphenous vein bypass graft: Case report and literature review.

OBJECTIVES: Arteriovenous fistulas (AVFs) of an in situ saphenous vein bypass can be managed surgically or through endovascular coil embolization. The complications associated with the surgical wounds required for side branch ligature can be minimized through selective vein ligature and interrupted small incisions, but endovascular methods are time-consuming and limited by vein size. In this case report, we describe percutaneous ultrasound (US)-guided balloon-assisted direct glue injection as an alternative treatment strategy for AVF closure. METHODS: We treated a patient with a delayed AVF in a femoral-popliteal in situ saphenous vein bypass. The patient came to our attention for the recurrence of chronic limb-threatening ischemia (CTLI) 4 years after the initial bypass creation. Ultrasound and computed tomography angiography (CTA) showed a double tandem graft in significant stenosis below an AVF connected with the deep venous system. Treatment included percutaneous angioplasty of the bypass stenosis and contemporary AVF closure via ultrasound-guided glue injection. RESULTS: We successfully performed endovascular angioplasty with a drug-eluting balloon of the bypass stenosis and ultrasound-guided fistula embolization with cyanoacrylate Glubran 2. Angiography after the procedure showed bypass graft patency, no residual stenosis, and complete closure of the AVF. Results were confirmed with US. CONCLUSIONS: Percutaneous embolization using glue could be a useful technique for AVF closure. It is a minimally invasive method that reduces the need for skin incisions during in situ saphenous grafting or endovascular revascularization.

Intra-breath oscillometry for the evaluation of lung function in children and adolescents with a history of preterm birth / Oscilometria intra-breath para avaliação da função pulmonar em crianças e adolescentes com história de prematuridade

ABSTRACT Objective: To assess respiratory system impedance (Zrs) and spirometric parameters in children and adolescents with and without a history of preterm birth. Methods: We evaluated a sample of 51 subjects between 11 and 14 years of age: 35 who had a history of preterm birth (preterm group) and 16 who had been born at term (full-term group). Lung function was measured by spirometry, spectral oscillometry, and intra-breath oscillometry. Results: Neither spirometry nor spectral oscillometry revealed any statistically significant differences between the preterm and full-term groups. However, intra-breath oscillometry demonstrated significant differences between the two groups in terms of the change in resistance, reactance at end-inspiration, and the change in reactance (p < 0.05 for all). Conclusions: Our findings suggest that abnormalities in Zrs persist in children and adolescents with a history of preterm birth and that intra-breath oscillometry is more sensitive than is spectral oscillometry. Larger studies are needed in order to validate these findings and to explore the impact that birth weight and gestational age at birth have on Zrs later in life.

RESUMO Objetivo: Avaliar a impedância do sistema respiratório (Zsr) e parâmetros espirométricos em crianças e adolescentes com e sem história de prematuridade. Métodos: Foi analisada uma amostra de 51 indivíduos entre 11 e 14 anos de idade: 35 com história de prematuridade (grupo pré-termo) e 16 nascidos a termo (grupo a termo). A função pulmonar foi medida por meio de espirometria, oscilometria espectral e oscilometria intra-breath. Resultados: A espirometria e a oscilometria espectral não revelaram diferenças estatisticamente significativas entre os grupos pré-termo e a termo. No entanto, a oscilometria intra-breath demonstrou diferenças significativas entre os dois grupos quanto à alteração da resistência, à reatância ao final da inspiração e à alteração da reatância (p < 0,05 para todas). Conclusões: Nossos achados sugerem que as anormalidades na Zsr persistem em crianças e adolescentes com história de prematuridade e que a oscilometria intra-breath é mais sensível do que a oscilometria espectral. São necessários estudos maiores para validar esses achados e para explorar o impacto do peso e idade gestacional ao nascer na Zsr mais tarde na vida.

Quasi-harmonic thermoelasticity of palladium, platinum, copper, and gold from first principles.

We calculate the temperature-dependent elastic constants (ECs) of palladium, platinum, copper and gold within the quasi-harmonic approximation using a first-principles approach and evaluating numerically the second derivatives of the Helmholtz free-energy with respect to strain at the minimum of the free-energy itself. We find an overall good agreement with the experimental data although the anomalies of palladium and platinum reported at room temperature are not reproduced. The contribution of electronic excitations is also investigated: we find that it is non-negligible for theC44ECs of palladium and platinum while it is irrelevant in the other cases. Its effect is not sufficient to explain the details of the anomalies found by experiments, not even when, in the case of platinum, we take into account the electron-phonon interaction. Lastly, the effect of the exchange and correlation functional is addressed and it is found that it is important atT= 0 K, while all functionals give similar temperature dependencies.

Italian odonates in the Pandora's box: A comprehensive DNA barcoding inventory shows taxonomic warnings at the Holarctic scale.

The Odonata are considered among the most endangered freshwater faunal taxa. Their DNA-based monitoring relies on validated reference data sets that are often lacking or do not cover important biogeographical centres of diversification. This study presents the results of a DNA barcoding campaign on Odonata, based on the standard 658-bp 5' end region of the mitochondrial COI gene, involving the collection of 812 specimens (409 of which barcoded) from peninsular Italy and its main islands (328 localities), belonging to all the 88 species (31 Zygoptera and 57 Anisoptera) known from the country. Additional BOLD and GenBank data from Holarctic samples expanded the data set to 1,294 DNA barcodes. A multi-approach species delimitation analysis involving two distance (OT and ABGD) and four tree-based (PTP, MPTP, GMYC and bGMYC) methods was used to explore these data. Of the 88 investigated morphospecies, 75 (85%) unequivocally corresponded to distinct molecular operational units, whereas the remaining ones were classified as 'warnings' (i.e. showing a mismatch between morphospecies assignment and DNA-based species delimitation). These results are in contrast with other DNA barcoding studies on Odonata showing up to 95% of identification success. The species causing warnings were grouped into three categories depending on if they showed low, high or mixed genetic divergence patterns. The analysis of haplotype networks revealed unexpected intraspecific complexity at the Italian, Palearctic and Holarctic scale, possibly indicating the occurrence of cryptic species. Overall, this study provides new insights into the taxonomy of odonates and a valuable basis for future DNA and eDNA-based monitoring studies.

Meconium microbiome and its relation to neonatal growth and head circumference catch-up in preterm infants.

The purpose was identify an association between meconium microbiome, extra-uterine growth restriction, and head circumference catch-up. MATERIALS AND METHODS: Prospective study with preterm infants born <33 weeks gestational age (GA), admitted at Neonatal Unit and attending the Follow-Up Preterm Program of a tertiary hospital. Excluded out born infants; presence of congenital malformations or genetic syndromes; congenital infections; HIV-positive mothers; and newborns whose parents or legal guardians did not authorize participation. Approved by the institution's ethics committee. Conducted 16S rRNA sequencing using PGM Ion Torrent meconium samples for microbiota analysis. RESULTS: Included 63 newborns, GA 30±2.3 weeks, mean weight 1375.80±462.6 grams, 68.3% adequate weight for GA at birth. Polynucleobacter (p = 0.0163), Gp1 (p = 0.018), and Prevotella (p = 0.038) appeared in greater abundance in meconium of preterm infants with adequate birth weight for GA. Thirty (47.6%) children reached head circumference catch-up before 6 months CA and 33 (52.4%) after 6 months CA. Salmonella (p<0.001), Flavobacterium (p = 0.026), and Burkholderia (p = 0.026) were found to be more abundant in meconium in the group of newborns who achieved catch-up prior to 6th month CA. CONCLUSION: Meconium microbiome abundance was related to adequacy of weight for GA. Meconium microbiome differs between children who achieve head circumference catch-up by the 6th month of corrected age or after this period.

Use of Azithromycin for the Prevention of Lung Injury in Mechanically Ventilated Preterm Neonates: A Randomized Controlled Trial.

INTRODUCTION: Macrolides have anti-inflammatory and immunomodulatory properties that give this class of antibiotics a role that differs from its classical use as an antibiotic, which opens new therapeutic possibilities. OBJECTIVE: The aim of this study was to evaluate the anti-inflammatory effect of azithromycin in preventing mechanical ventilation (MV)-induced lung injury in very-low-birth-weight preterm neonates. METHODS: This is a randomized, double-blind, placebo-controlled trial of preterm neonates who received invasive MV within 72 h of birth. Patients were randomized to receive intravenous azithromycin (at a dose of 10/mg/kg/day for 5 days) or placebo (0.9% saline) within 12 h of the start of MV. Two blood samples were collected (before and after intervention) for measurement of interleukins (ILs) and PCR for Ureaplasma. Patients were followed up throughout the hospital stay for the outcomes of death and broncho-pulmonary dysplasia defined as need for oxygen for a period of ≥28 days of life (registered at ClinicalTrials.gov, No. NCT03485703). RESULTS: Forty patients were analyzed in the azithromycin group and 40 in the placebo group. Five days after the last dose, serum IL-2 and IL-8 levels dropped significantly in the azithromycin group. There was a significant reduction in the incidence of death and O2 dependency at 28 days/death in azithromycin-treated patients regardless of the detection of Ureaplasma in blood. CONCLUSIONS: Azithromycin has anti-inflammatory effects, with a decrease in cytokines after 5 days of use and a reduction in death and O2 dependency at 28 days/death in mechanically ventilated preterm neonates.

Quasi-harmonic temperature dependent elastic constants: applications to silicon, aluminum, and silver.

We present ab-initio calculations of the quasi-harmonic temperature dependent elastic constants. The isothermal elastic constants are calculated at each temperature as second derivatives of the Helmholtz free energy with respect to strain and corrected for finite pressure effects. This calculation is repeated for a grid of geometries and the results interpolated at the minimum of the Helmholtz free energy. The results are compared with the quasi-static elastic constants. Thermodynamic relationships are used to derive the adiabatic elastic constants that are compared with the experimental measurements. These approaches are implemented for cubic solids in the thermo_pw code and are validated by applications to silicon, aluminum, and silver.

Defining microbial biomarkers for risk of preterm labor.

Preterm birth remains the main contributor to early childhood mortality. The vaginal environment, including microbiota composition, might contribute to the risk of preterm delivery. Alterations in the vaginal microbial community structure might represent a risk factor for preterm birth. Here, we aimed to (a) investigate the association between preterm birth and the vaginal microbial community and (b) identify microbial biomarkers for risk of preterm birth. Microbial DNA was isolated from vaginal swabs in a cohort of 69 women enrolled at hospital admission for their delivery. Microbiota was analyzed by high-throughput 16S rRNA sequencing. While no differences in microbial diversity measures appeared associated with the spontaneous preterm and full-term outcomes, the microbial composition was distinct for these groups. Differential abundance analysis showed Lactobacillus species to be associated with full-term birth whereas an unknown Prevotella species was more abundant in the spontaneous preterm group. Although we studied a very miscegenated population from Brazil, our findings were similar to evidence pointed by other studies in different countries. The role of Lactobacillus species as a protector in the vaginal microbiome is demonstrated to be also a protector of spontaneous preterm outcome whereas the presence of pathogenic species, such as Prevotella spp., is endorsed as a factor of risk for spontaneous preterm delivery.

Outcome and Feasibility after 7 Years of Therapeutic Hypothermia in Southern Brazil.

OBJECTIVE: This study aimed to describe the experience with a protocol of therapeutic hypothermia (TH) in southern Brazil. STUDY DESIGN: Newborns with gestational age > 35 weeks with evidence of perinatal asphyxia plus moderate or severe encephalopathy were recruited between March 2011 and November 2017. Whole-body hypothermia for 72 hours, starting within the first 6 hours of life was used. Survivors underwent magnetic resonance imaging (MRI) and electroencephalogram (EEG). The primary outcome was death during hospitalization and neurodevelopment assessed using the Bayley Scales of Infant Development III (BSID III) at 12 months of age. RESULTS: A total of 72 newborns were treated (41 with moderate encephalopathy and 31 with severe encephalopathy), of whom 16 died. MRI was performed in 56 patients, and 24 presented some alterations. Fifty-three patients had an EEG: 11 normal, 20 mildly altered, 12 moderately altered, and 10 severely altered. Forty patients were evaluated through BSID III: 45% presented with some delay in neurodevelopment, 8 (20%) had motor retardation, 15 (37.5%) had language delay, and 13 (32.5%) had a delay in cognitive development. CONCLUSION: Mortality and adverse events were similar to those described in large randomized controlled trials. TH is a safe and an effective method of neurologic protection in asphyxiated newborns in a developing country when performed adequately.

The vaginal microbial communities of healthy expectant Brazilian mothers and its correlation with the newborn's gut colonization.

The female lower genital tract harbors a complex microbial community essential for homeostasis and health. During pregnancy, the female body undergoes unique hormonal changes that contribute to weight gain as well as modulations in immune function that can affect microbiota composition. Several studies have described the vaginal microbiota of pregnant women from the USA, Europe and Mexico. Here we expand our knowledge about the vaginal microbial communities during the third trimester to healthy expectant Brazilian mothers. Vaginal samples were collected from patients delivering at the Hospital de Clínicas de Porto Alegre, Brazil. Microbial DNA was isolated from samples and the V4 region of the 16S rRNA gene was amplified and sequenced using the PGM Ion Torrent. Brazilian pregnant women presented three distinct types of microbial community at the time of labor. Two microbial communities, Cluster 1 and Cluster 3, presented an overall dominance of Lactobacillus while Cluster 2 tended to present higher diversity and richness, with the presence of Pseudomonas, Prevotella and other vaginosis related bacteria. About half of the Brazilian mothers sampled here had dominance of L. iners. The proportion of mothers without dominance of any Lactobacillus was higher in Brazil (22%) compared to UK (2.4%) and USA, where this community type was not detected. The vaginal microbiota showed significant correlation with the composition of the babies' gut microbiota (p-value = 0.002 with a R2 of 15.8%). Mothers presenting different vaginal microbiota shared different microorganisms with their newborns, which would reflect on initial colonizers of the developing newborns' gut.

Temperature-dependent atomic B factor: an ab initio calculation.

The Debye-Waller factor explains the temperature dependence of the intensities of X-ray or neutron diffraction peaks. It is defined in terms of the B matrix whose elements Bαß are mean-square atomic displacements in different directions. These quantities, introduced in several contexts, account for the effects of temperature and quantum fluctuations on the lattice dynamics. This paper presents an implementation of the B factor (8π2Bαß) in the thermo_pw software, a driver of Quantum ESPRESSO routines that provides several thermodynamic properties of materials. The B factor can be calculated from the ab initio phonon frequencies and displacements or can be estimated, although less accurately, from the elastic constants, using the Debye model. The B factors are computed for a few elemental crystals: silicon, ruthenium, magnesium and cadmium; the harmonic approximation at fixed geometry is compared with the quasi-harmonic approximation where the B factors are calculated accounting for thermal expansion. The results are compared with the available experimental data.