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BACKGROUND: Exposure to domestic violence by triggering repetitive distress and fear can affect neurodevelopmental and mental health in the short and long term. This, in turn, has been linked to an increased risk of substance abuse, such as alcohol abuse in adulthood. OBJECTIVE: The present study aimed to evaluate the association between exposure to violence from the father toward the mother and alcohol abuse in Peruvian women. DESIGN: Cross-sectional study. METHODS: We conducted a secondary analysis of data from the Peruvian Demographic and Family Health Survey (ENDES) of 2019. A total of 19,980 reproductive-aged women (15-49 years old) were surveyed using the Health Questionnaire during 2019. The dependent variable of the study was alcohol abuse, collected through self-report, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. Intimate partner violence (IPV; violence perpetrated by the father against the mother) was considered as the exposure variable. To assess the association of interest, we only considered observations with complete data and used binary logistic regression models, calculating crude odds ratios and adjusted odds ratios (aOR). For the multivariable model, we adjusted for confounding variables (age, marital status, education level, wealth index, ethnicity, residence, current smoker, depression, and IPV). RESULTS: We analyzed a final sample of 9953 women. The prevalence of interparental violence and alcohol abuse was 41.3% and 1.5%, respectively. We found that interparental violence was associated with higher odds of alcohol abuse (aOR: 2.10; 95% CI: 1.03-4.28) after adjusting for age, marital status, education level, wealth level, ethnicity, area of residence, current smoking, depression, and IPV. CONCLUSION: We identified that women of reproductive age who have been exposed to interparental violence were at higher odds of experiencing alcohol abuse issues.

Understanding the link between witnessing parental violence and alcohol abuse in Peruvian womenWitnessing violence between parents during childhood can leave deep emotional scars. This study explores whether such experiences are related to alcohol abuse among Peruvian women in their adult years. Using data from a national health survey in Peru, the experiences of nearly 20,000 women were analyzed to determine if witnessing violence between their parents during childhood was linked to alcohol problems later in life. Responses from the 2019 Peruvian Demographic and Family Health Survey were examined, focusing on women's reports of childhood exposure to violence between parents and current alcohol abuse, controlling for factors like age, education, and mental health. The study found that women who witnessed their parents engaging in violence were more likely to abuse alcohol as adults. About 41% of the women reported seeing such violence, and of these, a higher proportion struggled with alcohol compared to those who did not witness violence. Understanding the link between childhood experiences and adult behaviors can help develop targeted interventions to prevent alcohol abuse. This research highlights the need for support systems that help women cope with the emotional impacts of childhood trauma, potentially reducing alcohol-related problems in the future.

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Collision cross section (CCS) of organic compounds can be measured via Fourier transform-based mass spectrometry (MS) by modeling the decay rate of transient signals in the analyzer. Deriving CCS values of low-mass molecules (mass < 2000 Da and CCS < 500 Å2) with Orbitrap MS is challenging due to their high axial frequencies and small absolute variances in cross-sectional profiles. Here, we acquired mass spectra of progressively more complex low-mass analytes using commercial Orbitrap mass spectrometers. The transient signals were processed using Fast Fourier transform (FFT) and short-time Fourier transform (StFFT) to derive decay constants of multiple select ionic species from a single MS full-scan experiment. Decay constants were translated into CCS values using at least two internal standards in the same mass spectrum. Our results suggest target ionic species should have high S/N in order to derive CCS values with ≤0.5% uncertainty. Limitations in the precision of CCS measurements reflect local space charge effects that disturb ion motion in the analyzer. The derived CCS values of polymer like fragments of Ultramark 1621 and small molecules such as individual protonated amino acids can achieve average ±1% error with selection of internal standards across a wide mass range. Future studies need to optimize the strategy to select internal standards in order to improve the precision and accuracy of CCS measurements for small molecules via Orbitrap MS.

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BACKGROUND: The introduction of natural language processing (NLP) technologies has significantly enhanced the potential of self-administered interventions for treating anxiety and depression by improving human-computer interactions. Although these advances, particularly in complex models such as generative artificial intelligence (AI), are highly promising, robust evidence validating the effectiveness of the interventions remains sparse. OBJECTIVE: The aim of this study was to determine whether self-administered interventions based on NLP models can reduce depressive and anxiety symptoms. METHODS: We conducted a systematic review and meta-analysis. We searched Web of Science, Scopus, MEDLINE, PsycINFO, IEEE Xplore, Embase, and Cochrane Library from inception to November 3, 2023. We included studies with participants of any age diagnosed with depression or anxiety through professional consultation or validated psychometric instruments. Interventions had to be self-administered and based on NLP models, with passive or active comparators. Outcomes measured included depressive and anxiety symptom scores. We included randomized controlled trials and quasi-experimental studies but excluded narrative, systematic, and scoping reviews. Data extraction was performed independently by pairs of authors using a predefined form. Meta-analysis was conducted using standardized mean differences (SMDs) and random effects models to account for heterogeneity. RESULTS: In all, 21 articles were selected for review, of which 76% (16/21) were included in the meta-analysis for each outcome. Most of the studies (16/21, 76%) were recent (2020-2023), with interventions being mostly AI-based NLP models (11/21, 52%); most (19/21, 90%) delivered some form of therapy (primarily cognitive behavioral therapy: 16/19, 84%). The overall meta-analysis showed that self-administered interventions based on NLP models were significantly more effective in reducing both depressive (SMD 0.819, 95% CI 0.389-1.250; P<.001) and anxiety (SMD 0.272, 95% CI 0.116-0.428; P=.001) symptoms compared to various control conditions. Subgroup analysis indicated that AI-based NLP models were effective in reducing depressive symptoms (SMD 0.821, 95% CI 0.207-1.436; P<.001) compared to pooled control conditions. Rule-based NLP models showed effectiveness in reducing both depressive (SMD 0.854, 95% CI 0.172-1.537; P=.01) and anxiety (SMD 0.347, 95% CI 0.116-0.578; P=.003) symptoms. The meta-regression showed no significant association between participants' mean age and treatment outcomes (all P>.05). Although the findings were positive, the overall certainty of evidence was very low, mainly due to a high risk of bias, heterogeneity, and potential publication bias. CONCLUSIONS: Our findings support the effectiveness of self-administered NLP-based interventions in alleviating depressive and anxiety symptoms, highlighting their potential to increase accessibility to, and reduce costs in, mental health care. Although the results were encouraging, the certainty of evidence was low, underscoring the need for further high-quality randomized controlled trials and studies examining implementation and usability. These interventions could become valuable components of public health strategies to address mental health issues. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42023472120; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023472120.

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Objetive: Percutaneous occlusion of patent ductus arteriosus (PDA) has classically been performed entirely by fluoroscopy, however in recent years, transthoracic echocardiography (TE) has been used as an aid to fluoroscopy or entirely by echocardiography, which avoids access of femoral artery, use of contrast and decrease in time and dose of radiation exposure. The objective of this study was to evaluate the success rate with the use of TE in percutaneous PDA closure. Material and method: Descriptive, comparative, retrospective study between patients in whom PDA closure was performed with fluoroscopy plus angiography (group 1) and fluoroscopy plus ET (group 2), between January 2018 and December 2022. The data were obtained from the clinical history electronic and procedure report. Results: One hundred eight patients were analyzed, fluoroscopy group (n: 57) and TE (n: 51). The success rate in PDA occlusion using TE was 100% and 98% for the fluoroscopy group, with no statistically significant difference The average age of group 2 was 2.9 years, while the average age of group 1 was 5 years (p=0.001), the average fluoroscopy time in group 1 was 16.9 min and 4.71 min in group 2 (p < 0.001); the fluoroscopy dose in group 1 was 68.98 mGy and 5.17 mGy in group 2 (p<0.001). Krichenko, but without significant difference in both groups. Conclusions: The success rate of percutaneous PDA closure using echocardiography and fluoroscopy is appropiate, with a success rate similar to the classic technique. In addition, it makes it possible to reduce the dose and time of fluoroscopy, avoid the use of contrast, and access the femoral artery.

Objetivo: La oclusión percutánea del ductus arterioso persistente (DAP) clásicamente se ha realizado por fluoroscopía y angiografía; sin embargo, en los últimos años se está utilizando la ecocardiografía transtorácica (ETT) como ayuda a la fluoroscopía o íntegramente por ETT, lo que evita el acceso de arteria femoral, uso de contraste y disminución de tiempo y dosis exposición a la radiación. El objetivo del estudio fue evaluar la tasa de éxito con la utilización de la ETT en el cierre percutáneo del DAP. Materiales y métodos: Estudio descriptivo de tipo comparativo, retrospectivo, entre pacientes en quienes se realizó el cierre del DAP con fluoroscopía más angiografía (grupo 1) y fluoroscopía más ETT (grupo 2), entre enero 2018 y diciembre 2022. Los datos fueron obtenidos de la historia clínica electrónica y del informe del procedimiento. Resultados: Se analizaron 108 pacientes, de los cuales 57 pertenecen al grupo de fluoroscopía más angiografía y 51 al grupo de fluoroscopía más ETT. La tasa de éxito en la oclusión del DAP utilizando fluoroscopía más ETT fue del 100% y 98% para el grupo de fluoroscopía más angiografía, sin diferencia estadísticamente significativa. La edad promedio del grupo 2 fue de 2,9 años, mientras que la edad promedio del grupo 1 fue 5 años (p< 0,001), el tiempo promedio de fluoroscopía en el grupo 1 fue de 16,9 min y 4,7 min en el grupo 2 (p < 0,001); la dosis de fluoroscopía en el grupo 1 fue de 68,98 mGy y 5,17 mGy en el grupo 2 (p< 0,001). Se encontró que el tipo de DAP predominante fue el tipo A de Krichenko, pero sin diferencia significativa en ambos grupos. Conclusión: La tasa de éxito del cierre percutáneo del DAP con el uso de la ecocardiografía y fluoroscopia es adecuada, con un nivel de éxito similar a la técnica clásica, esto permite, además, disminuir la dosis y tiempo de fluoroscopia, evitar el uso de contraste y el acceso de la arteria femoral.

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RATIONALE: Characterization of Regolith And Trace Economic Resources (CRATER), an Orbitrap™-based laser desorption mass spectrometry instrument designed to conduct high-precision, spatially resolved analyses of planetary materials, is capable of answering outstanding science questions about the Moon's formation and the subsequent processes that have modified its (sub)surface. METHODS: Here, we describe the baseline design of the CRATER flight model, which requires <20 000 cm3  volume, <10 kg mass, and <60 W peak power. The analytical capabilities and performance metrics of a prototype that meets the full functionality of the flight model are demonstrated. RESULTS: The instrument comprises a high-power, solid-state, pulsed ultraviolet (213 nm) laser source to ablate the surface of the lunar sample, a custom ion optical interface to accelerate and collimate the ions produced at the ablation site, and an Orbitrap mass analyzer capable of discriminating competing isobars via ultrahigh mass resolution and high mass accuracy. The CRATER instrument can measure elemental and isotopic abundances and characterize the organic content of lunar surface samples, as well as identify economically valuable resources for future exploration. CONCLUSION: An engineering test unit of the flight model is currently in development to serve as a pathfinder for near-term mission opportunities.

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Studies of psychrophilic life on Earth provide chemical clues as to how extraterrestrial life could maintain viability in cryogenic environments. If living systems in ocean worlds (e.g., Enceladus) share a similar set of 3-mer and 4-mer peptides to the psychrophile Colwellia psychrerythraea on Earth, spaceflight technologies and analytical methods need to be developed to detect and sequence these putative biosignatures. We demonstrate that laser desorption mass spectrometry, as implemented by the CORALS spaceflight prototype instrument, enables the detection of protonated peptides, their dimers, and metal adducts. The addition of silicon nanoparticles promotes the ionization efficiency, improves mass resolving power and mass accuracies via reduction of metastable decay, and facilitates peptide de novo sequencing. The CORALS instrument, which integrates a pulsed UV laser source and an Orbitrap™ mass analyzer capable of ultrahigh mass resolving powers and mass accuracies, represents an emerging technology for planetary exploration and a pathfinder for advanced technique development for astrobiological objectives. Teaser: Current spaceflight prototype instrument proposed to visit ocean worlds can detect and sequence peptides that are found enriched in at least one strain of microbe surviving in subzero icy brines via silicon nanoparticle-assisted laser desorption analysis.

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Introduction: This study set out to examine the use of telehealth resources to tackle the coronavirus disease 2019 (COVID-19) pandemic in Latin America within the scope of national telehealth projects (NTPs). Methods: A qualitative study developed using ethnomethodology for appropriate understanding of how telehealth actions were carried out in practice during the COVID-19 pandemic within the scope of NTPs, in the following countries: Argentina, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Peru, and Uruguay. The study was carried out from October to 2020 to March 2021. The number of participations in the discussion groups, formed by coordinating teams of NTPs, totaled 90. Results were described in the worksheet completed according to the script. Each country reviewed its respective data, three times on average, in an effort to clarify actions developed. Results: Three groups of countries were identified: (1) Countries with a telehealth background that used these resources to tackle COVID-19 and thereby refined telehealth activities. Countries with greater experience in NTP design, such as Mexico, Colombia, Peru, and Argentina, were able to use a wide range of telehealth activities to tackle the pandemic, with offers of teleconsultation, teleguidance, telemonitoring to patients, and training of health professionals; (2) Countries with some telehealth activities to address COVID-19. Uruguay, Ecuador, El Salvador, and Costa Rica; and (3) Countries with no evidence of telehealth resource use during the pandemic. Honduras and Guatemala. Discussion: Most NTPs in Latin America have improved their telehealth activities, contributing to address the COVID-19 pandemic in Latin America.

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Astrobiology missions to ocean worlds in our solar system must overcome both scientific and technological challenges due to extreme temperature and radiation conditions, long communication times, and limited bandwidth. While such tools could not replace ground-based analysis by science and engineering teams, machine learning algorithms could enhance the science return of these missions through development of autonomous science capabilities. Examples of science autonomy include onboard data analysis and subsequent instrument optimization, data prioritization (for transmission), and real-time decision-making based on data analysis. Similar advances could be made to develop streamlined data processing software for rapid ground-based analyses. Here we discuss several ways machine learning and autonomy could be used for astrobiology missions, including landing site selection, prioritization and targeting of samples, classification of "features" (e.g., proposed biosignatures) and novelties (uncharacterized, "new" features, which may be of most interest to agnostic astrobiological investigations), and data transmission.

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Since the inception of mass spectrometry more than a century ago, the field has matured as analytical capabilities have progressed, instrument configurations multiplied, and applications proliferated. Modern systems are able to characterize volatile and nonvolatile sample materials, quantitatively measure abundances of molecular and elemental species with low limits of detection, and determine isotopic compositions with high degrees of precision and accuracy. Consequently, mass spectrometers have a rich history and promising future in planetary exploration. Here, we provide a short review on the development of mass analyzers and supporting subsystems (eg, ionization sources and detector assemblies) that have significant heritage in spaceflight applications, and we introduce a selection of emerging technologies that may enable new and/or augmented mission concepts in the coming decades.

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Extraterrestrial delivery of cyanide may have been crucial for the origin of life on Earth since cyanide is involved in the abiotic synthesis of numerous organic compounds found in extant life; however, little is known about the abundance and species of cyanide present in meteorites. Here, we report cyanide abundance in a set of CM chondrites ranging from 50 ± 1 to 2472 ± 38 nmol·g-1, which relates to the degree of aqueous alteration of the meteorite and indicates that parent body processing influenced cyanide abundance. Analysis of the Lewis Cliff 85311 meteorite shows that its releasable cyanide is primarily in the form of [FeII(CN)5(CO)]3- and [FeII(CN)4(CO)2]2-. Meteoritic delivery of iron cyanocarbonyl complexes to early Earth likely provided an important point source of free cyanide. Iron cyanocarbonyl complexes may have served as precursors to the unusual FeII(CN)(CO) moieties that form the catalytic centers of hydrogenases, which are thought to be among the earliest enzymes.

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RATIONALE: The investigation of cryogenic planetary environments as potential harbors for extant life and/or contemporary sites of organic synthesis represents an emerging focal point in planetary exploration. Next generation instruments need to be capable of unambiguously determining elemental and/or molecular stoichiometry via highly accurate mass measurements and the separation of isobaric interferences. METHODS: An Orbitrap™ analyzer adapted for spaceflight (referred to as the CosmOrbitrap), coupled with a commercial pulsed UV laser source (266 nm), was used to successfully characterize a variety of planetary analog samples via ultrahigh resolution laser desorption/ablation mass spectrometry. The materials analyzed in this study include: jarosite (a hydrous sulfate detected on Mars); magnesium sulfate (a potential component of the subsurface ocean on Europa); uracil (a nucleobase of RNA); and a variety of amino acids. RESULTS: The instrument configuration tested here enables: measurement of major elements and organic molecules with ultrahigh mass resolution (m/Δm ≥ 120,000, FWHM); quantification of isotopic abundances with <1.0% (2σ) precision; and identification of highly accurate masses within 3.2 ppm of absolute values. The analysis of a residue of a dilute solution of amino acids demonstrates the capacity to detect twelve amino acids in positive ion mode at concentrations as low as ≤1 pmol/mm2 while maintaining mass resolution and accuracy requirements. CONCLUSIONS: The CosmOrbitrap mass analyzer is highly sensitive and delivers mass resolution/accuracy unmatched by any instrument sent into orbit or launched into deep space. This prototype instrument, which maps to a spaceflight implementation, represents a mission-enabling technology capable of advancing planetary exploration for decades to come.

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Laser ablation ICP-MS enables streamlined, high-sensitivity measurements of rare earth element (REE) abundances in geological materials. However, many REE isotope mass stations are plagued by isobaric interferences, particularly from diatomic oxides and argides. In this study, we compare REE abundances quantitated from mass spectra collected with low-resolution (m/Δm = 300 at 5% peak height) and medium-resolution (m/Δm = 2500) mass discrimination. A wide array of geological samples was analyzed, including USGS and NIST glasses ranging from mafic to felsic in composition, with NIST 610 employed as the bracketing calibrating reference material. The medium-resolution REE analyses are shown to be significantly more accurate and precise (at the 95% confidence level) than low-resolution analyses, particularly in samples characterized by low (<µg/g levels) REE abundances. A list of preferred mass stations that are least susceptible to isobaric interferences is reported. These findings impact the reliability of REE abundances derived from LA-ICP-MS methods, particularly those relying on mass analyzers that do not offer tuneable mass-resolution and/or collision cell technologies that can reduce oxide and/or argide formation. Graphical Abstract ᅟ.

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The Mars Organic Molecule Analyzer (MOMA) instrument onboard the ESA/Roscosmos ExoMars rover (to launch in July, 2020) will analyze volatile and refractory organic compounds in martian surface and subsurface sediments. In this study, we describe the design, current status of development, and analytical capabilities of the instrument. Data acquired on preliminary MOMA flight-like hardware and experimental setups are also presented, illustrating their contribution to the overall science return of the mission. Key Words: Mars-Mass spectrometry-Life detection-Planetary instrumentation. Astrobiology 17, 655-685.

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The Mars Organic Molecule Analyzer (MOMA), a dual-source, ion trap-based instrument capable of both pyrolysis-gas chromatography mass spectrometry (pyr/GC-MS) and laser desorption/ionization mass spectrometry (LDI-MS), is the core astrobiology investigation on the ExoMars rover. The MOMA instrument will be the first spaceflight mass analyzer to exploit the LDI technique to detect refractory organic compounds and characterize host mineralogy; this mode of analysis will be conducted at Mars ambient conditions. In order to achieve high performance in the Martian environment while keeping the instrument compact and low power, a number of innovative designs and components have been implemented for MOMA. These include a miniaturized linear ion trap (LIT), a fast actuating aperture valve with ion inlet tube. and a Microelectromechanical System (MEMS) Pirani sensor. Advanced analytical capabilities like Stored Waveform Inverse Fourier Transform (SWIFT) for selected ion ejection and tandem mass spectrometry (MS/MS) are realized in LDI-MS mode, and enable the isolation and enhancement of specific mass ranges and structural analysis, respectively. We report here the technical details of these instrument components as well as system-level analytical capabilities, and we review the applications of this technology to Mars and other high-priority targets of planetary exploration.

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Fundamento y objetivo: Comparar 2 escalas para la valoración de pacientes con traumatismo craneoencefálico (TCE) leve, la regla canadiense (EC) y los criterios de New Orleans (NO), de acuerdo a su precisión diagnóstica, en pacientes que acuden a un servicio de urgencias hospitalario, así como determinar los valores predictivos más importantes. Método: Estudio transversal realizado en un hospital de primer nivel en el periodo de enero del 2011 a enero del 2013. Se incluyeron los pacientes con criterios de TCE leve. A todos los pacientes se les realizó una tomografía computarizada (TC) de cráneo como parte del protocolo interno y se completó con la EC y los criterios de NO. Consideramos como variable principal la presencia de lesiones traumáticas en el TC, y como variables secundarias la intervención neuroquirúrgica y el síndrome posconmocional. Se compararon la sensibilidad, especificidad, los valores predictivos y el índice de validez (IV) de la EC y de los criterios de NO en el subgrupo de pacientes con una puntuación en la escala de coma de Glasgow (GCS) de 15 puntos. Resultados: Se evaluaron un total de 217 pacientes, de los que 197 presentaban una puntuación en la GCS de 15 puntos. Ambas escalas mostraban un 100% de sensibilidad cuando se presentaba una lesión importante en el TC, la EC 100% (IC 95%: 97,4-100%) y los criterios de NO 100% (IC 95%: 97,4-100%), pero la EC consiguió mayores valores de especificidad 25,3% (IC 95%: 18,6-32%), valor predictivo positivo (VPP) e IV. Las 2 escalas mostraron un 100% de sensibilidad en relación con la intervención neuroquirúrgica, y la EC con criterios de alto riesgo consiguió, claramente, una mayor especificidad, VPP e IV de 55,2 (IC 95%: 8,3-62,2%) vs. 7,6 (IC 95%: 3,8-11,5%) de NO. Con respecto al síndrome posconmocional, los criterios de NO mostraron mayor sensibilidad 100% (IC 95%: 96,2-100%) y valores predictivos, aunque menor especificidad e IV comparado con la EC 76,9% (IC 95%: 50,2-100%). Conclusiones: Nuestro estudio demuestra la alta sensibilidad de la EC y de los criterios de NO en pacientes con TCE leve tanto para detectar una lesión clínica importante en el TC como la necesidad de una intervención neuroquirúrgica, así como una mejor especificidad de la EC comparada con los criterios de NO. Se recomienda la adopción de reglas de predicción clínica, en especial de la EC, para la solicitud de un TC de cráneo en pacientes con TCE leve (AU)

Background and objective: To compare two scales for assessment of patients with mild head injury. The Canadian CT Head Rule (CCHR) and New Orleans Criteria (NOC) according to their diagnostic accuracy in patients attending an emergency department, and to determine the most important predictive values. Method: Cross-sectional study in a first-level Hospital in the period of January 2011 to January 2013. Patients with mild head injury criteria were included. All the patients underwent a computed tomography (CT) of the head as part of internal protocol and the CCHR and NOC criteria were recorded for each patient. We consider the main variable the presence of traumatic lesions on CT and, as secondary variables, neurosurgical intervention and post-concussion syndrome. Sensitivity, specificity, predictive values and validity index (VI) of the CCHR and the NO criteria in the subgroup of patients with a Glasgow Coma Scale (GCS) score of 15 points were compared. Results: A total of 217 patients, of whom 197 had a GCS score of 15 points were evaluated. Both rules showed 100% sensitivity when a significant injury was presented in the CT, the CCHR 100% (95% CI: 97.4%-100%) and the NO criteria 100% (95% CI: 97.4%-100%); but the CCHR achieved higher values of specificity 25.3% (95% CI: 18.6%-32%), positive predictive value (PPV) and VI. The two rules showed a 100% sensitivity regarding neurosurgical intervention; however the CCHR with high-risk criteria showed better specificity, PPV and VI 55.2 (95% CI: 8.3%-62.2%) compared to the NO criteria 7.6 (95% CI: 3.8%-11.5%). With regard to post-concussion syndrome criteria NO criteria showed better sensitivity 100% (95% CI: 96.2%-100%) and predictive values, but lower specificity and VI compared with the CCHR 76.9% (95% CI: 50.2%-100%). Conclusions: Our study demonstrates the high sensitivity of the CCHR and the NO criteria in patients with mild head injury, both to detect a significant clinical lesion on CT or the need for neurosurgical intervention and better specificity of CCHR compared with NO criteria. The adoption of clinical prediction rules, especially the CCHR, to request a CT scan in patients with mild head injury should be recommended in the emergency department (AU)

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BACKGROUND AND OBJECTIVE: To compare two scales for assessment of patients with mild head injury. The Canadian CT Head Rule (CCHR) and New Orleans Criteria (NOC) according to their diagnostic accuracy in patients attending an emergency department, and to determine the most important predictive values. METHOD: Cross-sectional study in a first-level Hospital in the period of January 2011 to January 2013. Patients with mild head injury criteria were included. All the patients underwent a computed tomography (CT) of the head as part of internal protocol and the CCHR and NOC criteria were recorded for each patient. We consider the main variable the presence of traumatic lesions on CT and, as secondary variables, neurosurgical intervention and post-concussion syndrome. Sensitivity, specificity, predictive values and validity index (VI) of the CCHR and the NO criteria in the subgroup of patients with a Glasgow Coma Scale (GCS) score of 15 points were compared. RESULTS: A total of 217 patients, of whom 197 had a GCS score of 15 points were evaluated. Both rules showed 100% sensitivity when a significant injury was presented in the CT, the CCHR 100% (95% CI: 97.4%-100%) and the NO criteria 100% (95% CI: 97.4%-100%); but the CCHR achieved higher values of specificity 25.3% (95% CI: 18.6%-32%), positive predictive value (PPV) and VI. The two rules showed a 100% sensitivity regarding neurosurgical intervention; however the CCHR with high-risk criteria showed better specificity, PPV and VI 55.2 (95% CI: 8.3%-62.2%) compared to the NO criteria 7.6 (95% CI: 3.8%-11.5%). With regard to post-concussion syndrome criteria NO criteria showed better sensitivity 100% (95% CI: 96.2%-100%) and predictive values, but lower specificity and VI compared with the CCHR 76.9% (95% CI: 50.2%-100%). CONCLUSIONS: Our study demonstrates the high sensitivity of the CCHR and the NO criteria in patients with mild head injury, both to detect a significant clinical lesion on CT or the need for neurosurgical intervention and better specificity of CCHR compared with NO criteria. The adoption of clinical prediction rules, especially the CCHR, to request a CT scan in patients with mild head injury should be recommended in the emergency department.

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Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) enables spatially resolved quantitative measurements of major, minor and trace element abundances in igneous rocks and minerals with equal or better precision than many other in situ techniques, and more rapidly than labour-intensive wet chemistry procedures. Common applications for LA-ICP-MS in the Earth sciences centre on investigating the composition of natural and experimental geological materials, including: analysis of whole rock silicate glasses, flux-free pressed powder tablets and/or fused aliquots of materials; in situ probing of individual minerals, xenocrysts, fluid and melt inclusions, experimental run products, and siderophile-rich micronuggets; and multidimensional chemical mapping of complex (multiphase) materials.

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Mantle-derived melts and metasomatic fluids are considered to be important in the transport and distribution of trace elements in the subcontinental lithospheric mantle. However, the mechanisms that facilitate sulfur and metal transfer from the upper mantle into the lower continental crust are poorly constrained. This study addresses this knowledge gap by examining a series of sulfide- and hydrous mineral-rich alkaline mafic-ultramafic pipes that intruded the lower continental crust of the Ivrea-Verbano Zone in the Italian Western Alps. The pipes are relatively small (< 300 m diameter) and primarily composed of a matrix of subhedral to anhedral amphibole (pargasite), phlogopite and orthopyroxene that enclose sub-centimeter-sized grains of olivine. The 1 to 5 m wide rim portions of the pipes locally contain significant blebby and disseminated Fe-Ni-Cu-PGE sulfide mineralization. Stratigraphic relationships, mineral chemistry, geochemical modelling and phase equilibria suggest that the pipes represent open-ended conduits within a large magmatic plumbing system. The earliest formed pipe rocks were olivine-rich cumulates that reacted with hydrous melts to produce orthopyroxene, amphibole and phlogopite. Sulfides precipitated as immiscible liquid droplets that were retained within a matrix of silicate crystals and scavenged metals from the percolating hydrous melt, associated with partial melting of a metasomatized continental lithospheric mantle. New high-precision chemical abrasion TIMS U-Pb dating of zircons from one of the pipes indicates that these pipes were emplaced at 249.1 ± 0.2 Ma, following partial melting of lithospheric mantle pods that were metasomatized during the Eo-Variscan oceanic to continental subduction (~420-310 Ma). The thermal energy required to generate partial melting of the metasomatized mantle was most likely derived from crustal extension, lithospheric decompression and subsequent asthenospheric rise during the orogenic collapse of the Variscan belt (< 300 Ma). Unlike previous models, outcomes from this study suggest a significant temporal gap between the occurrence of mantle metasomatism, subsequent partial melting and emplacement of the pipes. We argue that this multi-stage process is a very effective mechanism to fertilize the commonly dry and refractory lower continental crust in metals and volatiles. During the four-dimensional evolution of the thermo-tectonic architecture of any given terrain, metals and volatiles stored in the lower continental crust may become available as sources for subsequent ore-forming processes, thus enhancing the prospectivity of continental block margins for a wide range of mineral systems.

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Evidence from recent Mars missions indicates the presence of perchlorate salts up to 1 wt % level in the near-surface materials. Mixed perchlorates and other oxychlorine species may complicate the detection of organic molecules in bulk martian samples when using pyrolysis techniques. To address this analytical challenge, we report here results of laboratory measurements with laser desorption mass spectrometry, including analyses performed on both commercial and Mars Organic Molecule Analyzer (MOMA) breadboard instruments. We demonstrate that the detection of nonvolatile organics in selected spiked mineral-matrix materials by laser desorption/ionization (LDI) mass spectrometry is not inhibited by the presence of up to 1 wt % perchlorate salt. The organics in the sample are not significantly degraded or combusted in the LDI process, and the parent molecular ion is retained in the mass spectrum. The LDI technique provides distinct potential benefits for the detection of organics in situ on the martian surface and has the potential to aid in the search for signs of life on Mars.

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