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The vertical structure of the observed stable boundary layer often deviates substantially from textbook profiles. Even over flat homogeneous surfaces, the turbulence may not be completely related to the surface conditions and instead generated by elevated sources of turbulence such as low-level jets and transient modes. In stable conditions, even modest surface heterogeneity can alter the vertical structure of the stable boundary layer. With clear skies and low wind speeds, cold-air drainage is sometimes generated by very weak slopes and induces a variety of different vertical structures. Our study examines the vertical structure of the boundary layer at three contrasting tower sites. We emphasize low wind speeds with strong stratification. At a given site, the vertical structure may be sensitive to the surface wind direction. Classification of vertical structures is posed primarily in terms of the profile of the heat flux. The nocturnal boundary layer assumes a variety of vertical structures, which can often be roughly viewed as layering of the heat-flux divergence (convergence). The correlation coefficient between the temperature and vertical velocity fluctuations provides valuable additional information for classification of the vertical structure. [ABSTRACT FROM AUTHOR]

In this paper, we make a complete revision about Nöther's theorems: The one which refers to the global symmetries, the theorem referring to the local ones, and the corresponding reciprocal theorems. We exemplify these theorems by applying them to a variety of situations. Particularly, we show, through the example of Kepler's problem, that the first reciprocal Nöther's theorem finds its maximal applicability only in the Hamiltonian formalism in which the dynamical symmetries are realizable. Finally, we expose the relation between Nöther's energy-momentum tensor and the metric one. We complement the information by treating, in appendix, Lévy-Leblond-Jackiw's formulation that intends to unify the two theorems. [ABSTRACT FROM AUTHOR]

This work discusses the electron transport mechanisms that we obtained as a function of the density of amorphous carbon (a-C) ultra-thin films. We calculated the density of states (total and projected), degree of electronic states' localization, and transmission function using the density functional theory and nonequilibrium Green's functions method. We generated 25 sample a-C structures using ab-initio molecular dynamics within the isothermal-isobaric ensemble. We identified three transport regimes as a function of the density, varying from semimetallic in low-density samples (≤2.4 g/cm³) to thermally activated in high-density (≥2.9 g/cm³) tetrahedral a-C. The middle-range densities (2.4 g/cm³ ≤ρ≤2.9 g/cm³) are characterized by resonant tunneling and hopping transport. Our findings offer a different perspective from the tight-binding model proposed by Katkov and Bhattacharyya [J. Appl. Phys. 113, 183712 (2013)], and agree with experimental observations in low-dimensional carbon systems [see S. Bhattacharyya, Appl. Phys. Lett. 91, 21 (2007)]. Identifying transport regimes is crucial to the process of understanding and applying a-C thin film in electronic devices and electrode coating in biosensors. [ABSTRACT FROM AUTHOR]

Background: Despite recent advances in the operative management of complex ventral hernia (CVH), significant challenges remain. Closure of large defects can have serious pathophysiological consequences due to chronic contraction and retraction of the lateral abdominal wall muscles. Certain features of CVH make repair technically demanding and time consuming, such as massive fascial defects, unusual hernia locations, involvement of other abdominal wall structures and previous tissue trauma.Methods: Preoperative assessment with three-dimensional volume rendered CT (3DVR-CT) imaging and an illustrative series of clinical cases is introduced for repair of CVH using laparoscopic approach.Results: CVH presented here include traumatic hernias involving extensive tissue trauma, massive ventral hernias with defects > 20 cm in width, hernias requiring additional procedures such as wiring of ribs, and hernias in difficult locations such as suprapubic and flank hernias. Specific techniques such as individually tailoring mesh and size, transfascial mesh straps fixation and transcutaneous defect closure will be discussed. All hernias in this series have been repaired laparoscopically (Lap) or laparoscopic-open-laparoscopic (LOL) technique with transcutaneous fascial closure. After hernia closure the mesh is placed in either an intra-peritoneal onlay mesh (IPOM) placement or modified Rives-Stoppa technique with pre-peritoneal mesh placement.Conclusion: CVH repair requires multidisciplinary planning with management tailored to each patient's clinical and surgical requirements. The surgeon must have a variety of surgical skills and strategies to address the multiple and/or atypical defects that affect these patients. [ABSTRACT FROM AUTHOR]

We review the construction of the gauge theory for semi-simple Lie groups by Utiyama in “Invariant Theoretical Interpretation of Interaction”[1]. It is shown an auxiliary field A μ a x must be introduced in order to keep the system of fields ϕ A (x) invariant under a transformation group depending on n parameters ϵ a (x). This auxiliary field interacts with ϕ through the covariant derivative ∇ μ ϕ A. We determine the transformation law for A μ a under the x μ-dependent Lie group and calculate the field strength F μν a (x). Moreover, we specify the conserved current J a μ related to the invariance of the complete system. The paper ends with the application of the general theory to the cases of the charged particle in an electromagnetic field and of the Yang-Mills potential under isotopic spin space transformations; we briefly address the matter of the gravitational field as a gauge theory; finally, we comment on the extension of Utiyama's theory for LA = LA [Aa μ ; ∂ ν A a μ ; ∂ ρ ∂ ν A a μ] (x). [ABSTRACT FROM AUTHOR]

Using ab initio computational techniques on crystal determined clusters, we report on the similarities and differences of Al50(C5(CH3)5)12, Ga23(N(Si(CH3)3)2)11, and Au102(SC7O2H5)44 ligand-protected clusters. Each of the ligand-protected clusters in this study shows a similar stable character which can be described via an electronic shell model. We show here that the same type of analysis leads consistently to derivation of a superatomic electronic counting rule, independently of the metal and ligand compositions. One can define the cluster core as the set of atoms where delocalized single-angular-momentum-character orbitals have high weights using a combination of Bader analysis and evaluation of Khon-Sham orbitals. Subsequently, one can derive the nature of the ligand-core interaction. These results yield further insight into the superatom analogy for the class of ligand-protected metal clusters. [ABSTRACT FROM AUTHOR]

Loss of small fragments (like AuL, AuL, AuL) have been found systematically in several MALDI and FAB experiments on thiolate-protected gold clusters of different sizes. When using the cluster AuL as parent cluster, the fragmented cluster AuL has been reported to be obtained in high proportion (L = SCHCHPh). Here we analyse a few possible fragmentation patterns of the well-known parent cluster AuL (L = SCH). Using DFT calculations we study the different atomic configurations obtained after a AuL fragment is lost from AuL. We found energetically favourable configurations that can be written as Au [AuL][AuL], where the modification can be described as a replacement of the long protecting unit by a short one (AuL → AuL). A full replacement ( z = 6) gives rise to a protected AuL cluster. This mechanism does not modify the super-atomic electronic structure of the gold core, i.e., all these fragments remain an 8 electron super-atom clusters exactly like the parent AuL. We suggest that the AuL cluster could be realized by using a bulky thiolate, such as the tert-butyl thiolate SC(CH) . [ABSTRACT FROM AUTHOR]

Electrical conductance through various nanocontacts between gold electrodes is studied by using the density functional theory, scalar-relativistic pseudopotentials, generalized gradient approximation for the exchange-correlation energy and the recursion-transfer-matrix method along with channel decomposition. The nanocontact is modeled with pyramidal fcc(100) tips and 1 to 5 gold atoms between the tips. Upon elongation of the contact by adding gold atoms between the tips, the conductance at Fermi energy EF evolves from G ≈ 3G0 to G ≈ 1G0 (G0 = 2e/h2). Formation of a true one-atom point contact, with G ≈ 1G0 and only one open channel, requires at least one atom with coordination number 2 in the wire. Tips that share a common vertex atom or tips with touching vertex atoms have three partially open conductance channels at EF, and the symmetries of the channels are governed by the wave functions of the tips. The long 5-atom contact develops conductance oscillations and conductance gaps in the studied energy range -3 ≤ E-EF ≤ 5 eV, which reflects oscillations in the local density of electron states in the 5-atom linear “gold molecule" between the electrodes, and a weak coupling of this “molecule" to the tips. [ABSTRACT FROM AUTHOR]

An experiment was carried out to evaluate the effects of different levels of water application during post-setting and post-veraison on wine quality of cv. Cabernet Sauvignon (Vitis vinifera L.) during the 2000-2001 and 2001-2002 growing seasons. The vineyard is located in the Pencahue Valley, VII Region of Chile (35°22′ S lat; 71°47′ W long). The 7 year-old vineyard was drip irrigated and trained in a vertical shoot positional system. Irrigation treatments were the application of 40, 70 and 100% of the real evapotranspiration (ETreal) during post-setting and post-veraison. The results showed that the best combination for wine quality was obtained by restricting water applications to 40% ETreal during post-setting and 70% ETreal during post-veraison, with significant increments in the global quality and wine sensory attributes. On the contrary, the worst wine quality (higher titratable acidity and low total concentrations of phenols and anthocyanins) was obtained with a water application of 100% of the ETreal during the whole growing period. [ABSTRACT FROM AUTHOR]

Nighttime data collected at the bottom of a valley located in southern Brazil are studied. The analyzed quantities include momentum and sensible heat fluxes, turbulence statistics and intermittency factors, and their relationship to the stability parameter. The proper interval for averaging and flux calculations is found to be 20 min, based on the comparison of the fluxes and the random error associated in their determination. Each data series is classified as calm or windy, according to the mean wind speed. A much better dependency of the variables in terms of the stability parameter is found under windy conditions. Analysis of the wind direction and topographic scales indicates that distortion effects under calm conditions affect the flow, while the flow is in local equilibrium for windy conditions. In this case, the sensible heat flux shows a minimum for a value of z/L=0.08, while the momentum flux and the normalized scales of the wind components and temperature decrease monotonically as the stability increases. An intermittency factor is proposed and shown to be larger (more intermittency) for more stable conditions. [ABSTRACT FROM AUTHOR]

Purpose: To assess 7-year outcomes after complex ventral hernia (CVH) repair using pre-operative Botulinum toxin A (BTA) injection and the Macquarie System of management. Methods: Clinical examination and functional non-contrast abdominal CT scans were used to assess complications and recurrences encountered in a prospective series of 88 consecutive CVH repairs using pre-operative BTA injection (200 or 300 units) between November 2012 and December 2019. Pre-operative progressive pneumoperitoneum (PPP) and/or component separation (CS) were also used in some cases. Results: All hernia defects (mean transverse width 12.9 ± 5.2 cm) were successfully closed using either laparoscopic or laparoscopic-assisted open techniques facilitated by pre-operative BTA injection. The mean pre-operative post-BTA lateral oblique length gain was 4.7 ± 2.2 cm/side (p < 0.001). In 43 patients with defects < 12 cm wide, closure was achieved using BTA-only in 33 (76.7%), BTA + PPP in 2 (4.7%), BTA + CS in 5 (11.6%) and BTA + PPP + CS in 3 (7.0%). In the remaining 45 patients with defects ≥ 12 cm wide, closure was achieved using BTA-only in 9 (20.0%), BTA + PPP in 11 (24.4%), BTA + CS in 5 (11.1%) and BTA + PPP + CS in 20 (44.4%). There was a significant correlation between increasing defect size and the need for 2 or more CVH closure procedures (χ2 = 25.28, p < 0.0005). There were no BTA complications. Two patients developed midline hernia recurrences. Conclusion: Pre-operative BTA injection of the abdominal wall is a safe procedure that facilitates hernia defect closure and reduces the need for CS, especially when defect size is less than 12 cm. BTA may also decrease the rate of hernia recurrence. [ABSTRACT FROM AUTHOR]

Our study examines the horizontal variation of the nocturnal surface air temperature by analyzing measurements from four contrasting networks of stations with generally modest topography. The horizontal extent of the networks ranges from 1 to 23 km. For each network, we investigate the general relationship of the horizontal variation of temperature to the wind speed, wind direction, near-surface stratification, and turbulence. As an example, the horizontal variation of temperature generally increases with increasing stratification and decreases with increasing wind speed. However, quantitative details vary significantly between the networks. Needed changes of the observational strategy are discussed. Significance Statement: We analyze nocturnal measurements from four different networks of surface stations over different types of terrain. We concentrate on the spatial variation of the surface air temperature that controls frost damage, fog formation, dispersion of particulates, and the effects of terrain changes on climate. For each network, our study examines the general relationship of the horizontal variation of temperature to the wind speed, wind direction, vertical variation of temperature, and turbulence. We identify important inadequacies of the observations and the need for future more appropriate network design including instrumental needs and choice of sites. [ABSTRACT FROM AUTHOR]

This study examines the spatial variability of the nocturnal wind field using eight networks of surface observations ranging in horizontal width from 500 m to 65 km. The wind field is partitioned into small-scale variability (submeso motions) and the spatially-averaged wind vector. The vector-averaged wind is analogous to the wind resolved by a numerical model, posed here in terms of the wind that is vector averaged over an observational network. The small-scale variability represents the unresolved subgrid (sub-network) variation estimated in terms of the spatial variation of the wind vector within the observational domain. The bulk formula for the spatially-averaged heat flux is modified to account for the subgrid variation of the wind field. Investigation of the spatial variability of the wind field is also motivated by the need to estimate the representativeness of observations of the wind vector at an individual measurement site with respect to the wind field over the surrounding landscape. The small-scale variability of the observed wind field is contrasted between the networks as a function of the spatially-averaged wind vector, stratification, size of the network, and the topography. A strong dependence on topography emerges in spite of different instrumentation, deployment strategy, and processing for each network. Even weak topography can be important. A better design for future observational networks is briefly discussed. [ABSTRACT FROM AUTHOR]

We reveal universal dynamical scaling behavior across adiabatic quantum phase transitions in networks ranging from traditional spatial systems (Ising model) to fully connected ones (Dicke and Lipkin-Meshkov-Glick models). Our findings, which lie beyond traditional critical exponent analysis and adiabatic perturbation approximations, are applicable even where excitations have not yet stabilized and, hence, provide a time-resolved understanding of quantum phase transitions encompassing a wide range of adiabatic regimes. We show explicitly that even though two systems may traditionally belong to the same universality class, they can have very different adiabatic evolutions. This implies that more stringent conditions need to be imposed than at present, both for quantum simulations where one system is used to simulate the other and for adiabatic quantum computing schemes. [ABSTRACT FROM AUTHOR]

Abstract: We present various molecular electronic descriptors of agonists and antagonists for GlycineB-iGluR-NMDA receptor with a view to identify computational measures that help differentiate between these two classes of biologically active compounds. We use as reference the glycine site in the NR1 subunit of the NMDA receptor (GlycineB-iGluR-NMDA). GlycineB-iGluR-NMDA receptor is important in learning and memory, and it is involved in various neurodegenerative diseases such as Alzheimer, Parkinson, and Huntington as well as in neuropathies such as schizophrenia and depression. We carried out quantum calculations at two levels, (1) B3LYP Density Functional (6-311G**), and (2) PM3 Hamiltonian for 168 molecules, of which 22 are agonists and 146 are antagonists. Regardless of the quantum mechanical level used we found a consistent signature of agonists versus antagonist action, the energy of the lowest unoccupied molecular orbital (LUMO). Effective differentiation of agonists and antagonists by a single molecular descriptor is seldom seen. We present a plausible electronic structure argument to rationalize these results. [Copyright &y& Elsevier]

INTRODUCTION: Tipe 1 Diabetes Mellitus (DM1) is a chronic metabolic disorder characterized by elevated levels of glycemia as a result of the alteration in insulin secretion. It is characterized by the destruction of pancreatic beta cells, which translates into an absolute deficit of this hormone and permanent dependence of exogenous insulin. CASE REPORT: Infant, 11 months 11 days old, consulted in the Pediatric Emergency room of the Hospital Clínico Herminda Martin, to present one day of irritability, crying without tears, perioral cyanosis, dry mucous, with regular feeding tolerance. In laboratory test, a Glycemia of 740 mg/dL, Ketonemia (+++), Glycosuria >1000 mg/dL, pH: 7.014. It is diagnosed with a diabetic ketoacidosis, as a complication of an early-onset DM1. It is hospitalized in the pediatric intensive care unit (PICU) of the HCHM, for stabilization and treatment. Evolve stable, so that on the 10th day of hospitalization, it's discharged with appropriated glycemia, regular insulin scheme, and mother's education. DISCUSSION: DM1 is a disease that happens mainly in children under 15 years old, specifically in the preschool and prepuberal group. In patients at early ages, the clinic frame can give it to the typical presentation usually found in books, but the debut of the disease may express highly variable and nonspecific symptoms, where the clinical suspicion and laboratory test plays a key role in the orientation and diagnosis. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Tipe 1 Diabetes Mellitus (DM1) is a chronic metabolic disorder characterized by elevated levels of glycemia as a result of the alteration in insulin secretion. It is characterized by the destruction of pancreatic beta cells, which translates into an absolute deficit of this hormone and permanent dependence of exogenous insulin. CASE REPORT: Infant, 11 months 11 days old, consulted in the Pediatric Emergency room of the Hospital Clínico Herminda Martin, to present one day of irritability, crying without tears, perioral cyanosis, dry mucous, with regular feeding tolerance. In laboratory test, a Glycemia of 740 mg/dL, Ketonemia (+++), Glycosuria >1000 mg/dL, pH: 7.014. It is diagnosed with a diabetic ketoacidosis, as a complication of an earlyonset DM1. It is hospitalized in the pediatric intensive care unit (PICU) of the HCHM, for stabilization and treatment. Evolve stable, so that on the 10th day of hospitalization, it's discharged with appropriated glycemia, regular insulin scheme, and mother's education. DISCUSSION: DM1 is a disease that happens mainly in children under 15 years old, specifically in the preschool and prepuberal group. In patients at early ages, the clinic frame can give it to the typical presentation usually found in books, but the debut of the disease may express highly variable and nonspecific symptoms, where the clinical suspicion and laboratory test plays a key role in the orientation and diagnosis. [ABSTRACT FROM AUTHOR]

Introduction: Repair of complex ventral hernia presents a significant challenge plagued by high morbidity and recurrence. Recent studies have demonstrated significant benefits achievable with preoperative Botulinum Toxin A (BTA) chemical component paralysis to the abdominal wall muscles, facilitating primary closure of complex ventral hernia defects. However, transversus abdominis is known to play an integral role in truncal stability, and its paralysis can result in unwanted physiological changes. This is the first study to report on selective administration of preoperative BTA to internal and external oblique muscles only, thus sparing transversus abdominis from paralysis.Methods: This is a prospective observational study of 46 patients who underwent either selective two-layer or standard three-layer abdominal wall muscle BTA injection prior to elective laparoscopic ventral hernia repair. Serial abdominal CT imaging was performed to compare defect size and length of the lateral abdominal musculature.Results: 46 patients received preoperative BTA injections (23 in each group). A comparison of gains achieved from chemical component paralysis demonstrated no statistically significant difference between the two groups. Fascial closure was achieved in all cases, with no post-operative sequelae of abdominal hypertension. There are no hernia recurrences to date.Conclusion: Preoperative selective muscle chemical component paralysis is an effective technique to counteract the chronic muscle retraction observed in large ventral hernias. Transversus abdominis plays a significant role in truncal and spinal stability, and sparing it from paralysis preserves an important component of abdominal wall physiology and does not detract from the ability to primarily close complex defects. [ABSTRACT FROM AUTHOR]

Oscillations in the horizontal components of the wind velocity associated with oscillations in air temperature during low–wind speed episodes are ubiquitous in the stable boundary layer and are labeled as wind meandering. The meandering structure is recognizable by a clear negative lobe in the Eulerian autocorrelation functions of the horizontal wind velocity components and of the sonic temperature and by a corresponding peak at low frequency in the velocity components and temperature spectra. These distinctive features are used to isolate meandering occurrences and to study its properties in relation to the classical description of the planetary stable boundary layer. It is shown that the ratio of the variance of the wind velocity vertical component over the variance of the composite of the wind velocity horizontal components splits the frequency distribution of meandering and nonmeandering events and divides the nocturnal boundary layer in two different regimes characterized by different turbulent properties. The data comparison with a turbulence model based on Rotta return to isotropy showed that meandering and nonmeandering cases may have similar dynamics. This suggests that meandering may not be connected to a laminarization of the flow and shows that the Rotta scheme may still describe the energetic transfer between wind velocity components in the very stable boundary layer if the Rotta similarity constant c depends on the flux Richardson number. The data confirm a c value of 2.2 for Rif = 0 compatible with its conventional value. The analysis presented refers to one year of continuous measurements on 10 levels carried out at a coastal site in southeastern Brazil. [ABSTRACT FROM AUTHOR]

The coexistence of wave‐like submeso motions and anisotropic intermittent turbulence in a night‐time stable boundary layer is investigated. Submeso motions of different characteristics and amplitudes interact with each other. These interactions may lead to intermittent turbulence production which alters the turbulent structure of the stable boundary layer. On the other hand, the production and transfer of turbulence affect the delicate balance of submeso motions. In this work, sonic anemometer data collected at 11 levels in southeastern Brazil have been used to study a case of a nocturnal boundary layer at a coastal site. The absence of forcing at the synoptic scale allows the development of a breeze circulation on which a low‐level jet of moderate intensity (4 m s−1) and low height (about 50 m) takes place. The jet evolution is coupled with dirty waves, while its full development is associated with gravity waves driven by a strong vertical temperature gradient. The layer centred at the low‐level jet nose is characterized by horizontal meandering and very weak turbulence intensity. The air far below and above the low‐level jet maximum experiences bursts of significant increase of the turbulence intensity, showing a three‐layer structure. The oscillations of the horizontal wind components exhibit the same frequency as the temperature oscillations, suggesting that the presence of an adequate temperature horizontal gradient is one of the fundamental drivers of the meandering phenomenon. The considered night has been studied by means of the Eulerian auto‐correlation functions for the detection of the meandering hours and their oscillation time‐scales, and by means of the continuous Morlet wavelet function for the detection of the gravity waves and the characterization of their spatial time‐scales and temporal evolution. [ABSTRACT FROM AUTHOR]

Eulerian low-wind temperature statistics are investigated through the analysis of sonic anemometer observations gathered in two experimental campaigns, the Urban Turbulent Project in Northern Italy and the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (Brazil). The observed auto-correlations and spectra functions are tested with the theoretical relationships previously proposed for the horizontal velocity components in low wind speed conditions. The comparison showed that the temperature field, similarly to the horizontal velocity field, presents a characteristic oscillatory behaviour with a distinct isolated spectrum peak frequency due to the wind meandering. The ratio between this frequency and the one associated to the horizontal velocity components is close to one. This, together with the similarity between the temperature and velocity spectra and auto-correlation functions, suggests that a dynamical link between temperature and velocity oscillations exists. [ABSTRACT FROM AUTHOR]

We present a detailed microstructural study comparing conventional carbon nanofibers (CNFs) and novel carbon hybrid CNF materials. The hybrid consists of CNFs grown on top of tetrahedral amorphous carbon (ta-C) thin films on silicon with nickel catalyst and Ti adhesion layers. The conventional CNFs were grown on silicon with nickel catalyst and Cr layers. Even though CNFs can be grown in both systems by tip growth, the micro- and nanoscale features are very different in the two systems. The crystalline structure of the CNF in the hybrid case changes from horizontal alignment to near-vertical alignment from the root to the tip and no bamboo structure is observed. The results show that micro- and nanoscale properties of CNFs grown under the same process conditions can be readily altered by using a sacrificial ta-C layer below the metallic layer to prevent the alloying of Ni with carbide-forming metals used as adhesion promoters and to act as an additional carbon source during the pre-annealing stage. The experimental results are further rationalized with the aid of assessed thermodynamic data and simulations based on density functional theory (DFT) with van der Waals (vdW) corrections. [ABSTRACT FROM AUTHOR]