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Understanding the structure in the nanoscopic region of water that is in direct contact with solid surfaces, so-called contact layer, is key to quantifying macroscopic properties that are of interest to e.g. catalysis, ice nucleation, nanofluidics, gas adsorption, and sensing. We explore the structure of the water contact layer on various technologically relevant solid surfaces, namely graphene, MoS[Formula: see text], Au(111), Au(100), Pt(111), and Pt(100), which have been previously hampered by time and length scale limitations of ab initio approaches or force field inaccuracies, by means of molecular dynamics simulations based on ab initio machine learning potentials built using an active learning scheme. Our results reveal that the in-plane intermolecular correlations of the water contact layer vary greatly among different systems: Whereas the contact layer on graphene and on Au(111) is predominantly homogeneous and isotropic, it is inhomogeneous and anisotropic on MoS[Formula: see text], on Au(100), and on the Pt surfaces, where it additionally forms two distinct sublayers. We apply hydrodynamics and the theory of the hydrophobic effect, to relate the energy corrugation and the characteristic length-scales of the contact layer with wetting, slippage, the hydration of small hydrophobic solutes and diffusio-osmotic transport. Thus, this work provides a microscopic picture of the water contact layer and links it to macroscopic properties of liquid/solid interfaces that are measured experimentally and that are relevant to wetting, hydrophobic solvation, nanofluidics, and osmotic transport.

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The monetary cost of corrosion is currently estimated at 3 to 4% of the global GDP considering direct costs exclusively. However, no study to date has quantified the environmental impact associated with steel corrosion. Here, we determined that the CO2 emissions associated with the steelmaking required to replace corroded steel will be 4.1-9.1% of the total by 2030 considering the European Union and recent U.S. greenhouse gas reduction targets. We suggest that implementing corrosion management best-practices could drastically reduce the greenhouse gas emissions associated with the replacement of corroded steel and emphasize the need for coordinated international efforts.

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Sarcoidosis is a complex disease of unknown etiology characterized by the presence of granulomatous inflammation. Though various immune system pathways have been implicated in disease, the relationship between the genetic determinants of sarcoidosis and other inflammatory disorders has not been characterized. Herein, we examined the degree of genetic pleiotropy common to sarcoidosis and other inflammatory disorders to identify shared pathways and disease systems pertinent to sarcoidosis onset. To achieve this, we quantify the association of common variant polygenic risk scores from nine complex inflammatory disorders with sarcoidosis risk. Enrichment analyses of genes implicated in pleiotropic associations were further used to elucidate candidate pathways. In European-Americans, we identify significant pleiotropy between risk of sarcoidosis and risk of asthma (R2=2.03%; P=8.89 × 10-9), celiac disease (R2=2.03%; P=8.21 × 10-9), primary biliary cirrhosis (R2=2.43%; P=2.01 × 10-10) and rheumatoid arthritis (R2=4.32%; P=2.50 × 10-17). These associations validate in African Americans only after accounting for the proportion of genome-wide European ancestry, where we demonstrate similar effects of polygenic risk for African-Americans with the highest levels of European ancestry. Variants and genes implicated in European-American pleiotropic associations were enriched for pathways involving interleukin-12, interleukin-27 and cell adhesion molecules, corroborating the hypothesized immunopathogenesis of disease.

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To probe the influence of hydrogen bonding on the electronic structure of ammonia, gas phase and aqueous NH3 have been investigated using soft X-ray absorption (XAS), resonant inelastic soft X-ray scattering (RIXS), and electronic structure calculations including dynamical effects. Strong spectral differences in the XAS scans as well as in the RIXS spectra between gas phase and aqueous NH3 are attributed to orbital mixing with the water orbitals, dipole-dipole interactions, differences in vibronic coupling, and nuclear dynamics on the time-scale of the RIXS process. All of these effects are consequences of hydrogen bonding and the impact of the associated orbitals, demonstrating the power of XAS and RIXS as unique tools to study hydrogen bonding in liquids.

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A recent genome-wide association study in a German population and two subsequent studies in European populations found that a non-synonymous single-nucleotide polymorphism (SNP), rs1049550, within the annexin A11 (ANXA11) gene was associated with susceptibility to sarcoidosis. We sought to identify additional ANXA11 variants independently associated with sarcoidosis, determine whether any sarcoidosis-associated ANXA11 variants were associated with chest radiographic phenotypes, and explore human leukocyte antigen (HLA) SNP-SNP interactions with ANXA11. A total of 209 SNPs spanning 100 kb including the 5' promoter, coding, and 3' untranslated regions of ANXA11 were genotyped for 1689 sarcoidosis cases and 1252 controls. After adjustment for rs1049550, two additional novel ANXA11 sarcoidosis associations were identified only in African Americans--rs61860052 (odds ratio (OR)=0.62; 95% confidence interval (CI)=0.40-0.97) and rs4377299 (OR=1.31; 95% CI=1.06-1.63). These associations were more pronounced in radiologically-classified Scadding stage IV sarcoidosis cases. We also identified a significant SNP-SNP interaction between rs1049550 and a sarcoidosis risk SNP (rs9268839) near the HLA-DRA locus. This further genetic dissection of ANXA11 may provide additional insight into the immune dysregulation characteristic of sarcoidosis pathophysiology.

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Acute kidney injury (AKI) is an independent risk factor for mortality in critically ill patients whose epidemiology has been made unclear in the past by the use of different definitions across various studies. The RIFLE consensus definition has provided a unifying definition for AKI leading to large retrospective studies in different countries. The present study is a prospective observational multicenter study designed to prospectively evaluate all incident admissions in 10 Intensive Care Units (ICUs) in Italy and the relevant epidemiology of AKI. A simple user-friendly web-based data collection tool was created with the scope to serve for this study and to facilitate future multicenter collaborative efforts. We enrolled 601 consecutive patients into the study; 25 patients with End-Stage Renal Disease were excluded leaving 576 patients for analysis. The median age was 66 (IQR 53-76) years, 59.4% were male, while median SAPS II and APACHE II scores were 43 (IQR 35-54) and 18 (IQR 13-24), respectively. The most common diagnostic categories for ICU admission were: respiratory (27.4%), followed by neurologic (17%), trauma (14.4%), and cardiovascular (12.1%). Crude ICU and hospital mortality were 21.7% and median ICU length of stay was 5 days (IQR 3, 14). Of 576 patients, 246 patients (42.7%) had AKI within 24 hours of ICU admission while 133 developed new AKI later during their ICU stay. RIFLE-initial class was Risk in 205 patients (54.1%), Injury in 99 (26.1%) and Failure in 75 (19.8%). Progression of AKI to a worse RIFLE class was seen in 114 patients (30.8% of AKI patients). AKI patients were older, with higher frequency of common risk factors. 116 AKI patients (30.6%) fulfilled criteria for sepsis during their ICU stay, compared to 33 (16.7%) of non-AKI patients (P<0.001). 48 patients (8.3%) were treated with renal replacement therapy (RRT) in the ICU. Patients were started on RRT a median of 2 (IQR 0-6) days after ICU admission. Among AKI patients, they were started on RRT a median of 1 (IQR 0-4) days after fulfilling criteria for AKI. Median duration of RRT was 5 (IQR 2-10) day. AKI patients had a higher crude ICU mortality (28.8% vs. non-AKI 8.1%, P<0.001) and longer ICU length of stay (median 7 days vs. 3 days [non-AKI], P<0.001). Crude ICU mortality and ICU length of stay increased with greater severity of AKI. Two hundred twenty five patients (59.4% of AKI patients) had complete recovery of renal function, with a SCr at time of ICU discharge which was ≤120% of baseline; an additional 51 AKI patients (13.5%) had partial renal recovery, while 103 (27.2%) had not recovered renal function at the time of death or ICU discharge. Septic patients had more severe AKI, and were more likely to receive RRT with less frequency of renal function recovery. Patients with sepsis had higher ICU mortality and longer ICU stay. The study confirms previous analyses describing RIFLE as an optimal classification system to stage AKI severity. AKI is indeed a deadly complication for ICU patients where the level of severity correlated with mortality and length of stay. The tool developed for data collection resulted user friendly and easy to implement. Some of its features including a RIFLE class alert system, may help the treating physician to collect systematically AKI data in the ICU and possibly may guide specific decision on the institution of renal replacement therapy.

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Genome-wide linkage and association studies have uncovered variants associated with sarcoidosis, a multiorgan granulomatous inflammatory disease. African ancestry may influence disease pathogenesis, as African-Americans are more commonly affected by sarcoidosis. Therefore, we conducted the first sarcoidosis genome-wide ancestry scan using a map of 1384 highly ancestry-informative single-nucleotide polymorphisms genotyped on 1357 sarcoidosis cases and 703 unaffected controls self-identified as African-American. The most significant ancestry association was at marker rs11966463 on chromosome 6p22.3 (ancestry association risk ratio (aRR)=1.90; P=0.0002). When we restricted the analysis to biopsy-confirmed cases, the aRR for this marker increased to 2.01; P=0.00007. Among the eight other markers that demonstrated suggestive ancestry associations with sarcoidosis were rs1462906 on chromosome 8p12, which had the most significant association with European ancestry (aRR=0.65; P=0.002), and markers on chromosomes 5p13 (aRR=1.46; P=0.005) and 5q31 (aRR=0.67; P=0.005), which correspond to regions we previously identified through sib-pair linkage analyses. Overall, the most significant ancestry association for Scadding stage IV cases was to marker rs7919137 on chromosome 10p11.22 (aRR=0.27; P=2 × 10(-5)), a region not associated with disease susceptibility. In summary, through admixture mapping of sarcoidosis we have confirmed previous genetic linkages and identified several novel putative candidate loci for sarcoidosis.

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BACKGROUND: The aim of this study was to test if different recruitment maneuver (RM) patterns, that achieve the same maximum pressure for the same length of time in humans, have a similar efficacy on alveolar recruitment, intrathoracic vascular pressures and flows, and on cardiac function and ventricular filling. METHODS: Forty patients were randomly allocated to undergo different RM patterns: sustained inflation (SI) or pressure controlled ventilation (PCV). The RM methods tested are as follows: SI was achieved by raising peak inspiratory pressure to 45 cmH(2)O and sustaining it for 40 seconds. The PCV was set to obtain a 45 cmH(2)O peak inspiratory pressure for 2 minutes, I:E 1:2, PEEP 16 RR 8/min. During the study period, patients were mechanically ventilated to obtain a volume of 6 mL/kg, FiO(2) 0.7, PEEP 14, RR 14, Pplateau < or =30 cmH(2)O according to the ARDSnet trial. All patients were sedated and paralyzed during the study period. All patients were given i.v. norepinephrine. Heart rate, pulse oxymetry, blood pressure, pulmonary artery catheter data (C.I., PVRI, MPAP, PAOP, SvO(2), CVP), and arterial and right heart side venous blood gas analysis data (ph, PaO(2), PaCO(2), SatO(2), HCO(3)(-), SvO(2)) were recorded before and immediately after the lung recruitment maneuver. The static compliance of the respiratory system (CRS) was recorded. Echocardiographic spot evaluations before and after RM were obtained in all cases. RESULTS: Central venous pressure increased during RM. Mean pulmonary artery pressure, pulmonary capillary wedge pressure and pulmonary vascular resistance index were reduced during PCV RM compared to SI RM (P<0.05). The right ventricle stroke work index decreased to a major extent during PCV RM (P<0.05). The P/F ratio was significantly increased after PCV RM compared to SI RM (P<0.05). PaCO(2) levels were similar in the two groups. Compared to baseline, the Qs/Qt decreased significantly after the PCV recruitment maneuver. Ventricular end-diastolic and end-systolic areas decreased during both RM protocols, but they were decreased to a greater extent after SI RM than after PCV RM (P<0.05). The eccentricity index increased from baseline after the SI RM (P<0.05). CONCLUSION: Given its comparable, or even superior, performance over the SI RM, we favor the PCV technique over the time-honored SI maneuver.

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AIM: Target controlled infusion intravenous anesthesia is a growing phenomenon. Nowadays, many anesthesiologists feel the need to monitor depth of anesthesia during total intravenous anesthesia, even though it is not a standard technique worldwide. Spectral Entropy (SE) is a relatively new depth of anesthesia index. The aim of this study was to investigate whether predicted site-effect propofol concentrations, A-line Autoregressive Index (AAI) and SE values are useful for predicting loss of verbal contact (LVC) and loss of consciousness (LOC) during steady-state conditions. METHODS: Forty-four patients scheduled for elective major abdominal surgery were recruited. All patients were unpremedicated. A target controlled infusion of propofol was administered using Schnider's pharmacokinetic model. The initial propofol infusion provided a site-effect concentration of 1.0 mcg mL-1, and was increased stepwise by 1.0 mcg mL-1 every 4 minutes until the concentration reached 6.0 mcg mL-1. A 4 minute interval was chosen to assure that steady state site-effect concentrations were obtained. AAI, SE and propofol site-effect concentrations were recorded when LVC occurred and also when LOC occurred. Population values for predicted site-effect concentrations at the clinical endpoints were estimated and correlated with AAI and SE values. RESULTS: In our study for LOC the effect-site concentration to include 90% of patients was 5.85 ?mcg mL-1 (5.70-5.90) and 3.4 mcg mL-1 (3.24-3.60) for LVC. In this study, 90% of patients lost verbal contact at an AAI value of 68 (64.6-71.4) and an SE value of 68.2 (66.2-70.2). LOC occurred in 90% of patients at an AAI value of 39.2 (37.2-41.1) and an SE value of 40.2 (38.1-41.3). CONCLUSIONS: LOC and LVC occur within a defined range of predicted site-effect concentrations. More emphasis should be given to site-effect concentrations. SE and AAI have similar values at different endpoints and similar correlation with Ceprop. AAI and SE are both useful tools in predicting both LVC and LOC.

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Sarcoidosis is a systemic granulomatosis of unknown etiology despite being described over 100 years ago. While both genetic predisposition and environmental exposures have been proposed as playing a role in this disease, there have not been any systematic investigations of gene-environmental interaction in this disease. In the ACCESS dataset, detailed environmental histories and high resolution HLA class II typing were performed on 476 cases of newly diagnosed sarcoidosis and 476 matched controls from the patients' community. We evaluated gene-environmental interactions in exposures or HLA class II alleles that were present in > 5% of the population and had an odd ratio of > 1.0. Four exposures and four HLA Class II alleles met these criteria and were evaluated. Significant interaction was observed between HLA DRB1*1101 and insecticide exposure at work (p < 0.10) and suggestive interaction was observed between HLA DRB1*1101 and exposure to mold and musty odors and DRB1*1501 and insecticide exposure at work (P < 0.15). In addition, HLA DRB1*1101 and insecticide exposure at work was associated with extrapulmonary sarcoidosis, specifically cardiac sarcoidosis and hypercalcemia (p<0.05) and HLA DRB1*1101 and exposure to molds and musty odors was associated with pulmonary only sarcoidosis (P < 0.05). These studies suggest that sarcoidosis is due to an interaction of genetic predisposition and environmental exposure in at least some cases of sarcoidosis. Future studies in defined phenotypes of sarcoidosis may be necessary to define environmental and genetic associations with sarcoidosis.

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Gross deformation of the spinal needle shaft or the tip may occur during spinal needle insertion. During a one-year period, three cases of severe deformation of 27-gauge, 3.5 inch Whitacre spinal needles (B-Braun) occurred during standard spinal anesthesia in otherwise healthy patients. During this one-year period, we collected cut-bevel-point needles when bone impact occurred and compared them to the points of identical unused needles under a microscope. We believe that these microdeformations may be the cause of anatomical damage. We should be aware of even small resistance during spinal needle insertion because of the possibilities of severe deformation and injury of the anatomical structures, or of dramatic in situ breakage of the spinal needle. We should also be vigilant with respect to bone contact of the spinal needle, because needle points are damaged and can cause dural lacerations with subsequent cerebrospinal fluid leakage.

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The sarcoidosis genetic analysis (SAGA) study previously identified eight chromosomal regions with suggestive evidence for linkage to sarcoidosis susceptibility in African-American sib pairs. Since the clinical course of sarcoidosis is variable and likely under genetic control, we used the affected relative pair portion of the SAGA sample (n=344 pairs) to perform multipoint linkage analyses with covariates based on pulmonary and organ involvement phenotypes. Chest radiographic resolution was the pulmonary phenotype with the highest LOD (logarithm of the backward odds, or likelihood ratio) score of 5.11 at D1S3720 on chromosome 1p36 (P=4 x 10(-5)). In general, higher LOD scores were attained for covariates that modeled clustered organ system involvement rather than individual organ systems, with the cardiac/renal group having the highest LOD score of 6.65 at chromosome 18q22 (P=2 x 10(-5)). The highest LOD scores for the other three organ involvement groups of liver/spleen/bone marrow, neuro/lymph and ocular/skin/joint were 3.72 at 10p11 (P=0.0004), 5.16 at 7p22 (P=4 x 10(-5)) and 2.93 at 10q26 (P=0.001), respectively. Most of the phenotype linkages did not overlap with the regions previously found linked to susceptibility. Our results suggest that genes influencing clinical presentation of sarcoidosis in African Americans are likely to be different from those that underlie disease susceptibility.

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Ventilation in the prone position is a valid choice in the treatment of trauma patients with acute respiratory distress syndrome (ARDS). Two cases of trauma patients with ARDS treated in the prone position are described. The technique was very easy to use and safe. The prone position technique proved very useful in the treatment of post-traumatic ARDS in these 2 cases.

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Scombroid fish poisoning (scombrotoxism, scombroid ichthyotoxicosis) is a food-related illness typically associated with the consumption of dark and white meat fish. Two patients presented to the emergency department. Metilprednisone 1000 mg and ranitidine 150 mg were administered initially. A large amount of crystalloids and colloids in in combination with vasoactive drugs were required to maintain normopressure. Levels of histamine and N-methylhistamine were far above the normal mean. Carboxyhemoglobin levels were also tested to exclude a superimposition of carbon monoxide intoxication. In both cases, major symptoms occurred and were treated aggressively. Early goal directed fluid therapy corrected the DO2/VO2 unbalance, due to a distributive pattern of hypovolemic impending shock, and permitted a rapid stabilisation of both patients. It is important to recognize the syndrome as an intoxication (rather than an allergic reaction) so that the source of the toxin can be identified and further cases prevented. It is also important to investigate where the fish was cooked (i.e. in an open space vs. closed space), to exclude the possibility of a concomitant carbon monoxide intoxication, which would require transfer the patient to a hospital facility equipped with a hyperbaric chamber.

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AIM: The A-line autoregressive index (AAI) and the Bispectral Index Score (BIS) are two commercially available indexes of anesthetic depth widely used in clinical practice. The aim of the current study was to compare the accuracy of AAI, BIS, Schnider's predicted effect-site concentration of propofol (Ce propofol) to assess depth of anesthesia. METHODS: Forty-four patients scheduled for major elective abdominal surgery received target effect-site controlled infusion of propofol. Target effect-site (Ce propofol) was started at 1.5 mug/mL and increased every 4 min by 1.0 microg/mL until 5.5 microg/mL were achieved. At every step sedation level was estimated, using AAI, BIS, Observer's Assessment of Alertness/Sedation scale (OAA/S), loss of eyelash reflex and Ce propofol. RESULTS: We enrolled 44 patients, 20 males and 24 females, ASA I/II 18/26, 48+/-10 years, 68.2+/-9 kg, 165+/-7.1 cm, body mass index (BMI) 25+/-3.5. At increasing Ce propofol BIS-AAI values decreased progressively (BIS range 97-38) (AAI range 97-17). Values of BIS < or = 50, of AAI < or = 48 and of Ce propofol > or = 5.1 resulted in OAA/S=0, while values of BIS < or = 62, AAI < or = 53 and Ce propofol < or = 3.5 resulted in OAA/S=2. Loss of eyelash reflex occurred when values were BIS < or = 64 and AAI < or 61. CONCLUSION: BIS, AAI, propofol site effect concentration revealed information on sedation level and consciousness but no gold standard yet exists because of consistent overlap between ''conscious'' and ''not conscious'' states.

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BACKGROUND: The purpose of this study was to evaluate the feasibility of primary inguinal repair with open tension-free and sutureless technique using a new polypropylene "patch and plug system" (Prolene 3D patch), and the quality of the treatment in terms of reduction of postoperative discomfort. METHODS: Fifty-six consecutive patients, mean age 54.5+/-11.2 years, with primary unilateral uncomplicated inguinal hernia, were treated in a day-surgery setting. Collected data included: pain scores at 24 hours, 72 hours, and 7, 15, and 30 days after operation, analgesic medications, return to work and to heavy house and/or moderate sporting activities, and quality of life as measured by Short Form 36 health survey questionnaire (SF-36) before the operation and at 6 months follow-up. RESULTS: Postoperative pain was low: the mean visual analog scale (VAS) scores were 2.8 at 24 h, 1.8 at 72 h, and 0.9, 0.3, and 0.04 at 7, 15, and 30 days, respectively. Analgesic drugs were not used by 66.0% (n=37) of the patients. The mean global time to return to work and to heavy activities was 9.9+/-4.6 and 14.6+/-7.0, days, respectively. Patient satisfaction showed a significant improvement in all SF-36 domain scores at 6 months follow-up (P<0.001). There were no major complications, recurrences, or mortality. CONCLUSIONS: The new mesh seems to satisfy all requirements of a feasible, reliable, and effective device for repairing primary inguinal hernia with high patient comfort.

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Fermion antibunching was observed on a beam of free noninteracting neutrons. A monochromatic beam of thermal neutrons was first split by a graphite single crystal, then fed to two detectors, displaying a reduced coincidence rate. The result is a fermionic complement to the Hanbury Brown and Twiss effect for photons.