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OBJECTIVES Acute respiratory failure is common in pediatric hematopoietic cell transplant recipients and has a high mortality. However, respiratory prognostic markers have not been adequately evaluated for this population. Our objectives are to assess respiratory support strategies and indices of oxygenation and ventilation in pediatric allogeneic hematopoietic cell transplant patients receiving invasive mechanical ventilation and investigate how these strategies are associated with mortality. DESIGN Retrospective, multicenter investigation. SETTING Twelve U.S. pediatric centers. PATIENTS Pediatric allogeneic hematopoietic cell transplant recipients with respiratory failure. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Two-hundred twenty-two subjects were identified. PICU mortality was 60.4%. Nonsurvivors had higher peak oxygenation index (38.3 [21.3-57.6] vs 15.0 [7.0-30.7]; p < 0.0001) and oxygen saturation index (24.7 [13.8-38.7] vs 10.3 [4.6-21.6]; p < 0.0001), greater days with FIO2 greater than or equal to 0.6 (2.4 [1.0-8.5] vs 0.8 [0.3-1.6]; p < 0.0001), and more days with oxygenation index greater than 18 (1.4 [0-6.0] vs 0 [0-0.3]; p < 0.0001) and oxygen saturation index greater than 11 (2.0 [0.5-8.8] vs 0 [0-1.0]; p < 0.0001). Nonsurvivors had higher maximum peak inspiratory pressures (36.0 cm H2O [32.0-41.0 cm H2O] vs 30.0 cm H2O [27.0-35.0 cm H2O]; p < 0.0001) and more days with peak inspiratory pressure greater than 31 cm H2O (1.0 d [0-4.0 d] vs 0 d [0-1.0 d]; p < 0.0001). Tidal volume per kilogram was not different between survivors and nonsurvivors. CONCLUSIONS In this cohort of pediatric hematopoietic cell transplant recipients with respiratory failure in the PICU, impaired oxygenation and use of elevated ventilator pressures were common and associated with increased mortality.

The critically endangered spotted handfish (Brachionichthys hirsutus) is restricted to a limited number of locations in south-eastern Tasmania, Australia. As is often the case for rare species, conducting statistically adequate surveys for B. hirsutus can be costly and time consuming due to the low probability of encountering individuals. For the first time we used a highly efficient and rigorous Global Positioning System (GPS) parameterised underwater visual census (GUVC) to survey B. hirsutus abundance within all nine known local populations in the Derwent Estuary within one season. In addition, a benthic microhabitat assessment was conducted simultaneously using a GoPro® camera attached to diver to determine B. hirsutus microhabitat preferences. B. hirsutus local populations varied between sites, with densities ranging from 1.58 to 43.0 fishes per hectare. B. hirsutus demonstrates a strong preference for complex microhabitat features, such as depressions and ripple formations filled with biogenic substrates (e.g. shells) but avoids simple, low relief microhabitats (e.g. sand flats) and areas dominated by ephemeral, filamentous algae. Complex microhabitats may enable B. hirsutus to avoid predators, increase forage opportunities or provide higher quality spawning sites. This first wide-scale application of GUVC for B. hirsutus allowed us to survey a larger number of sites than previously possible to provide a robust reference point for future long-term monitoring.

The microservice architecture provides an efficient manner to allocate computational resources since each microservice can be individually scaled. Despite its benefits, there are still challenges regarding the cooperation among different microservices in order to provide elaborated business processes. In this paper, we propose Beethoven, an event-driven lightweight platform for microservice orchestration that eases the creation of complex applications that use microservice data flows. The platform is composed of a reference architecture and an orchestration language. The reference architecture has been instantiated by using the Spring Cloud Netflix ecosystem. To demonstrate the feasibility of the Beethoven platform, an example application has been developed. All artifacts produced as part of this work are available.

Contains fulltext : 182539.pdf (Publisher’s version ) (Closed access) Calcium/calmodulin-dependent protein kinase II (CAMK2) is one of the first proteins shown to be essential for normal learning and synaptic plasticity in mice, but its requirement for human brain development has not yet been established. Through a multi-center collaborative study based on a whole-exome sequencing approach, we identified 19 exceedingly rare de novo CAMK2A or CAMK2B variants in 24 unrelated individuals with intellectual disability. Variants were assessed for their effect on CAMK2 function and on neuronal migration. For both CAMK2A and CAMK2B, we identified mutations that decreased or increased CAMK2 auto-phosphorylation at Thr286/Thr287. We further found that all mutations affecting auto-phosphorylation also affected neuronal migration, highlighting the importance of tightly regulated CAMK2 auto-phosphorylation in neuronal function and neurodevelopment. Our data establish the importance of CAMK2A and CAMK2B and their auto-phosphorylation in human brain function and expand the phenotypic spectrum of the disorders caused by variants in key players of the glutamatergic signaling pathway.

Decagonite is the second natural quasicrystal, after icosahedrite (Al63Cu24Fe13), and the first to exhibit the crystallographically forbidden decagonal symmetry. It was found as rare fragments up to ~60 mm across in one of the grains (labeled number 126) of the Khatyrka meteorite, a CV3 carbonaceous chondrite. The meteoritic grain contains evidence of a heterogeneous distribution of pressures and temperatures that occurred during impact shock, in which some portions of the meteorite reached at least 5 GPa and 1200 °C. Decagonite is associated with Al-bearing trevorite, diopside, forsterite, ahrensite, clinoenstatite, nepheline, coesite, pentlandite, Cu-bearing troilite, icosahedrite, khatyrkite, taenite, Al-bearing taenite, and steinhardtite. Given the exceedingly small size of decagonite, it was not possible to determine most of the physical properties for the mineral. A mean of seven electron microprobe analyses (obtained from three different fragments) gave the formula Al70.2(3)Ni24.5(4)Fe5.3(2), on the basis of 100 atoms. A combined TEM and single-crystal X-ray diffraction study revealed the unmistakable signature of a decagonal quasicrystal: a pattern of sharp peaks arranged in straight lines with 10-fold symmetry together with periodic patterns taken perpendicular to the 10-fold direction. For quasicrystals, by definition, the structure is not reducible to a single three-dimensional unit cell, so neither cell parameters nor Z can be given. The likely space group is P105/mmc, as is the case for synthetic Al71Ni24Fe5. The five strongest powder-diffraction lines [ d in A (I/I0)] are: 2.024 (100), 3.765 (50), 2.051 (45), 3.405 (40), 1.9799 (40). The new mineral has been approved by the IMA-NMNC Commission (IMA2015-017) and named decagonite for the 10-fold symmetry of its structure. The find ing of a second natural quasicrystal informs the longstanding debate about the stability and robustness of quasicrystals among condensed matter physicists and demonstrates that mineralogy can continue to surprise us and have a strong impact on other disciplines.

Objectives:Although there are similarities in the pathophysiology of acute respiratory distress syndrome in adults and children, pediatric-specific practice patterns, comorbidities, and differences in outcome necessitate a pediatric-specific definition. We sought to create such a definition.Design:A

Steinhardtite is a new mineral from the Khatyrka meteorite; it is a new allotropic form of aluminum. It occurs as rare crystals up to ~10 μm across in meteoritic fragments that contain evidence of a heterogeneous distribution of pressures and temperatures during impact shock, in which some portions of the meteorite reached at least 5 GPa and 1200 °C. The meteorite fragments contain the high-pressure phases ahrensite, coesite, stishovite, and an unnamed spinelloid with composition Fe3– x Si x O4 ( x ≈ 0.4). Other minerals include trevorite, Ni-Al-Mg-Fe spinels, magnetite, diopside, forsterite, clinoenstatite, nepheline, pentlandite, Cu-bearing troilite, icosahedrite, khatyrkite, cupalite, taenite, and Al-bearing taenite. Given the exceedingly small grain size of steinhardtite, it was not possible to determine most of the physical properties for the mineral. A mean of 9 electron microprobe analyses (obtained from two different fragments) gave the formula Al0.38Ni0.32Fe0.30, on the basis of 1 atom. A combined TEM and single-crystal X-ray diffraction study revealed steinhardtite to be cubic, space group Im 3 m , with a = 3.0214(8) A, and V = 27.58(2) A3, Z = 2. In the crystal structure [ R 1 = 0.0254], the three elements are disordered at the origin of the unit cell in a body-centered-cubic packing (α-Fe structure type). The five strongest powder-diffraction lines [ d in A ( I/I ) ( hkl )] are: 2.1355 (100) (110); 1.5100 (15) (200); 1.2329 (25) (211); 0.9550 (10) (310); 0.8071 (30) (321). The new mineral has been approved by the IMA-NMNC Commission (2014-036) and named in honor of Paul J. Steinhardt, Professor at the Department of Physics of Princeton University, for his extraordinary and enthusiastic dedication to the study of the mineralogy of the Khatyrka meteorite, a unique CV3 carbonaceous chondrite containing the first natural quasicrystalline phase icosahedrite. The recovery of the polymorph of Al described here that contains essential amounts of Ni and Fe suggests that Al could be a contributing candidate for the anomalously low density of the Earth’s presumed Fe-Ni core.

BACKGROUND: Heated and humidified high-flow nasal cannula (HFNC) is a widely used form of respiratory support; however, data regarding optimal flows for a given patient size or disease state are lacking. A comprehensive study of the physiologic effects of HFNC is needed to better understand the mechanisms of action. The objective of the current study was to quantify the effect of HFNC settings in age-specific, anatomically correct nasal airways and spontaneously breathing lung models. We hypothesized that there is an effect of flow on pressure and ventilation. METHODS: Three-dimensionally printed upper airway models of a preterm neonate, term neonate, toddler, small child, and adult were affixed to the ASL 5000 test lung to simulate spontaneous breathing with age-appropriate normal ventilation parameters. CO2 was introduced to simulate profound hypercapneic respiratory failure with an end-tidal partial pressure of carbon dioxide (PETCO2) of 90 ± 1 mm Hg. Two commercially available HFNC systems were applied to the airway models, and PEEP, inspired CO2, and exhaled CO2 (PETCO2) were recorded for 6 min across a range of flow. RESULTS: Increasing HFNC flow provided a non-linear increase in PEEP in closed-mouth models, with maximum tested flows generating 6 cm H2O in the preterm neonate to 20 cm H2O in the small child. Importantly, PEEP decreased by approximately 50% in open-mouth models. Increasing HFNC flow improved expiratory CO2 elimination to a certain point, above which continued increases in flow had minimal additional effect. This change point ranged from 4 L/min in the preterm neonate to 10 L/min in the small child. CONCLUSIONS: These findings may help clinicians understand the effects of HFNC at different settings and may inform management guidelines for patients with respiratory failure.

Mobile cloud computing (MCC) and context-aware computing (CAC) are research topics in growing evidence. The former seeks to leverage cloud computing features to improve the performance of mobile applications and reduce the energy consumption of mobile devices, while the latter seeks effective ways to build applications that react to changes in its context environment. This short-course aims at presenting main concepts, solutions, and technologies related to the integration of MCC and context-aware applications. We will present different motivational scenarios, examples of applications, as well as a practical guide to the development of a context-aware multimedia Android application using the framework CAOS. In addition, we will highlight research challenges and opportunities that come with such integration.

There was an increase in purchases via credit card via smartphones with the growth of electronic commerce. It becomes more convenient and faster to just scan the image of the credit card than to enter the data of the card. In this work, a mobile system is presented that digitizes the credit card number and generates the recognized digits. The system, when scanning the data printed on the face of the credit card, applies digital image processing techniques for image enhancement and performs image digit recognition through the Template Matching technique. Using a test database containing 50 different credit card templates, a 75% hit rate was achieved on recognition.

ContextCurrent software systems have increasingly implemented context-aware adaptations to handle the diversity of conditions of their surrounding environment. Therefore, people are becoming used to a variety of context-aware software systems (CASS). This context-awareness brings challenges to the software construction and testing because the context is unpredictable and may change at any time. Therefore, software engineers need to consider the dynamic context changes while testing CASS. Different test case design techniques (TCDT) have been proposed to support the testing of CASS. However, to the best of our knowledge, there is no analysis of these proposals on the advantages, limitations and their effective support to context variation during testing. ObjectiveTo gather empirical evidence on TCDT concerned with CASS by identifying, evaluating and synthesizing knowledge available in the literature. MethodTo undertake a secondary study (quasi-Systematic Literature Review) on TCDT for CASS regarding their assessed quality characteristics, used coverage criteria, test type, and test technique. ResultsFrom 833 primary studies published between 2004 and 2014, just 17 studies regard the design of test cases for CASS. Most of them focus on functional suitability. Furthermore, some of them take into account the changes in the context by providing specific test cases for each context configuration (static perspective) during the test execution. These 17 studies revealed five challenges affecting the design of test cases and 20 challenges regarding the testing of CASS. Besides, seven TCDT are not empirically evaluated. ConclusionA few TCDT partially support the testing of CASS. However, it has not been observed evidence on any TCDT supporting the truly context-aware testing, which that can adapt the expected output based on the context variation (dynamic perspective) during the test execution. It is an open issue deserving greater attention from researchers to increase the testing coverage and ensure users confidence in CASS.

Currently, mobile applications have become increasingly complex. One trend is the usage of contextual information gathered from device sensors and external data sources, which are used to improve the user experience when using mobile applications. As the amount of sensing data increases as well as the complexity of context inference procedures, it leads to an undesirable situation where the mobile device has not enough resources (e.g., memory capacity, processing speed, and battery power) to perform some computation tasks. This paper addresses this issue by proposing CAOS, a software platform that employs the offloading approach to enhance mobile context-aware applications. CAOS allows mobile application developers to offload rocesses and data into cloud and cloudlets infrastructures, aiming at improving the overall application performance and saving battery power. In order to assess our proposal, a reference implementation was built, and experiments were performed in order to evaluate performance and energy consumption of our proposal. Results showed gains in both aspects in most of scenarios, which denote the feasibility of the proposed solution.

We report on a fragment of the quasicrystal-bearing CV3 carbonaceous chondrite Khatyrka recovered from fine-grained, clay-rich sediments in the Koryak Mountains, Chukotka (Russia). We show higher melting-point silicate glass cross-cutting lower melting-point Al-Cu-Fe alloys, as well as unambiguous evidence of a reduction-oxidation reaction history between Al-Cu-Fe alloys and silicate melt. The redox reactions involve reduction of FeO and SiO2 to Fe and Fe-Si metal, and oxidation of metallic Al to Al2O3, occurring where silicate melt was in contact with Al-Cu-Fe alloys. In the reaction zone, there are metallic Fe and Fe-Si beads, aluminous spinel rinds on the Al-Cu-Fe alloys, and Al2O3 enrichment in the silicate melt surrounding the alloys. From this and other evidence, we demonstrate that Khatyrka must have experienced at least two distinct events: first, an event as early as 4.564 Ga in which the first Al-Cu-Fe alloys formed; and, second, a more recent impact-induced shock in space that led to transformations of and reactions between the alloys and the meteorite matrix. The new evidence firmly establishes that the Al-Cu-Fe alloys (including quasicrystals) formed in outer space in a complex, multi-stage process.

Purpose Requiring PaO2/FiO2 ratio (PF) to define ARDS may bias towards children with cardiovascular dysfunction and hypoxemia. We sought to evaluate (1) the Berlin definition of ARDS in children using PF; (2) the effect of substituting SpO2/FiO2(SF) ratio; (3) differences between patients with and without arterial blood gases; and (4) the ability of SpO2 and PaO2 indices to discriminate ICU mortality.

Mobile devices are multipurpose and multi-sensor equipments supporting applications able to adapt their behavior according to changes in the user's context (device, location, time, etc.). Meanwhile, the development of mobile and context-aware software is not a simple task, mostly due to the peculiar characteristics of these devices. Although several solutions have been proposed to facilitate their development, reuse is not systematically used throughout the software development life-cycle. In this paper, we discuss an approach for the development of mobile and context-aware software using the Software Product Line (SPL) paradigm. Furthermore, a Nested SPL for the domain of mobile and context-aware applications is presented, lessons learned in the SPL development are discussed and a product for a context-aware visit guide is shown.

In this issue of Critical Care Medicine [1], members of the Brazilian Pediatric ARDS Study Group present a prospective validation of the Berlin Definition of ARDS [2] using an observational cohort from eight pediatric intensive care units in Brazil. Much like a previous validation of the Berlin Definition for younger children [3], the authors found that stratification into mild, moderate and severe categories of ARDS based on PF ratio better classified mortality than the AECC classification, and, like the previous pediatric validation, mortality did not differ between mild and moderate ARDS, but the severe group had significantly higher mortality. This validation is important for clinical care and research as it provides pediatric specific data regarding the performance of the Berlin Definition. However, it is important to consider this validation in the context of the broader picture of pediatric ARDS, and whether ultimately the Berlin Definition is the most appropriate definition to use for pediatric ARDS [4, 5]. The methodology and choices made by the investigators in this study highlight important ambiguities and practice pattern differences between adult and pediatric providers, which may have large implications for diagnosing pediatric ARDS. First, the authors chose in this validation to select the worst PF ratio the patient attained at any point during their ICU stay to stratify risk. This is a salient, and often overlooked issue with regards to ARDS severity stratification. The main goal of different risk severity groups in the Berlin Definition surrounds potential risk benefit profiles of therapeutic interventions. Therefore, the “timing” of when ARDS severity is assessed becomes crucial. A PF ratio of < 100 several days into the course of mechanical ventilation may have substantially different implications than a PF ratio < 100 within the first 24 hours of ventilation [6-9]. The PF ratio several days into the course of mechanical ventilation, or several days after the initial diagnosis of ARDS, may be a marker of adequacy (or inadequacy) of response to therapy, and variability in ventilator management. Given the multi-center nature of this cohort study, and the lack of completely standardized approaches to ventilator management (including PEEP, FiO2, Recruitment Maneuvers), it becomes even more crucial to use early values of PF ratio (i.e. within the first 24 hours of ventilation) to stratify risk. These issues will not be unique to these 8 centers; there is significant variability in ventilator or other management across pediatric centers, which may directly influence the PF ratio, particularly several days into the course of ventilation [10, 11]. Some of these issues can be overcome by using a measure of hypoxemia less subject to variability in practice, such as oxygenation index (OI), to stratify risk [12]. To that end, a pediatric specific definition of ARDS has been proposed by the Pediatric Acute Lung Injury Consensus Conference [13], in which OI is used as the primary metric for ARDS diagnosis and risk stratification for mechanically ventilated children. Moreover, PALICC recommends that epidemiologic studies report the performance of this this risk stratification method using data from the first 24 hours of ARDS diagnosis, to minimize the potential effect of practice pattern variability [13]. Ultimately, a later measure of hypoxemia (beyond the first day) may be important for therapies considered for patients who are not “initial responders,” and this study highlights that hypoxemia severity beyond the first day of ARDS diagnosis has important prognostic implications. A second important issue surrounds practice patterns with regards to arterial blood gasses. In this study, daily arterial blood gas (ABG) measurement was routine for all mechanically ventilated patients in these 8 intensive care units. However, pediatric and adult data suggest that the increased use of noninvasive mechanical ventilation in and outside of ICUs in combination with infrequent ABG sampling results in under recognition of ARDS in children and adults [11, 14-17]. Although routine, daily ABG sampling in this study helps to avoid this problem, the ABG data is acquired at discrete, arbitrary time points that may not reflect the condition of the patient throughout the day. Second, some centers reserve ABGs or arterial catheters for patients with significant hemodynamic compromise, rather than simply hypoxemia [18]. Therefore, there is an inherent selection bias regarding ABGs for ARDS diagnosis which may be related to disease severity or may not reflect the condition of the patient throughout the day. This may, in part, explain the lower number of patients identified with mild or moderate hypoxemia, and the minimal differences in risk of mortality between those with mild or moderate hypoxemia, as these deaths may be from cardiovascular causes. However, for generalizability it becomes imperative that the diagnosis of ARDS not be dependent on clinician behavior regarding a procedure (such as an ABG). For this reason, PALICC recommendations for diagnosis of ARDS allow for pulse-oximetry based criteria (Oxygen Saturation Index (OSI) and SpO2/FiO2 (SF) Ratio) to be substituted when an ABG is not available [13]. Third, the study investigators should be applauded on their attempt to standardize interpretation of bilateral infiltrates on chest radiograph for the purposes of this study. It appears as if their common training exercise between the study investigators and a radiologist resulted in good agreement regarding the presence of pulmonary edema and bilateral infiltrates. This is one of the first pediatric studies to demonstrate that such a method could result in similar, reproducible interpretation of bilateral infiltrates [3, 19]. However, it is still unclear just how necessary bilateral infiltrates are in the definition of ARDS. While bilateral infiltrates are meant to distinguish lobar processes like pneumonia from the diffuse injury seen in ARDS, chest radiographs demonstrate only modest sensitivity and specificity to detect areas of inflammation or infiltrate [20] [21-24]. Moreover, there are conflicting data whether presence or absence of bilateral infiltrates on CXR adds any prognostic value after controlling for the degree of hypoxemia [7, 25-29]. For this reason, the PALICC recommendations for diagnosis of ARDS have simplified radiographic criteria to patients with pulmonary parenchymal disease, in an attempt to improve disease recognition. However, PALICC continues to recommend tracking bilateral infiltrates, to determine the relevance on outcome [13]. If bilateral infiltrates are important for the definition, we must determine optimal methods for standardization of interpretation, which can be used both for clinical care and research. It is possible we can learn from the investigators of this study, to mimic their methodology and apply it on a broader scale. Finally, this manuscript highlights the potential differences and ambiguities in “lung protective” ventilator settings and modes of ventilation between adult and pediatric practice. As highlighted in this study, pressure control (PC) and pressure regulated volume control (PRVC) modes of ventilation are used much more commonly in pediatrics [11, 30]. Adult data regarding settings to minimize VILI are based on the square wave flow pattern of volume control ventilation, rather than the decelerating flow of PC or PRVC [31]. Hence extrapolation of tidal volume (which is frequently the response variable) targets become difficult, particularly with a lack of pediatric data to support that tidal volume has a significant association with mortality when decelerating flow patterns are used [32]. Driving pressure may be the more relevant metric for pediatric ARDS, but there is paucity of data in pediatrics to suggest what these pressure targets should be. To that end, the concept of plateau pressure (as compared to peak pressure) has less meaning with the decelerating flow patterns of PC or PRVC, and it is unclear whether the inspiratory hold maneuvers to measure plateau pressure are done universally across institutions. The same issues are highlighted with compliance measurements, where variability in methods of assessment of tidal volume (location of measurement, circuit compensation, predicted versus actual body weight), as well as which pressure is used (peak versus plateau) influence the reproducibility and generalizability of compliance measurements in studies [33]. To this end, the PALICC group has recommended future research into reproducible and reliable methods to report compliance, tidal volume, and pressure in clinical studies, to enable direct comparison [13]. Ultimately, the authors should be applauded for providing this first pediatric specific prospective validation of the Berlin Definition, highlighting the potential for successful application of pieces of the Berlin Definition to pediatric ARDS. However, pediatric specific practice patterns and the pathophysiology of pediatric ARDS warrant a pediatric specific definition of ARDS, which can be applied universally for children taken care of across the world [13].

There is a trade-off between the frequency of telemetry locations (fix interval) and battery life when using Global Positioning System (GPS) collars. In general, decreasing the fix interval lowers the effective battery life of the collar. However, the strong relationship between fix interval and movement metrics is often underappreciated. Mean movement rates, maximum movement rates, total distance estimates, and some screening algorithms change dramatically with different fix intervals, particularly for highly mobile animals such as caribou (Rangifer tarandus), and must be interpreted in relation to the fix interval used to collect the data. We used a multi-year, high-resolution data set from GPS collars with 2-hr fix intervals deployed on female caribou of the Teshekpuk Caribou Herd, Alaska, USA, 2006–2011, to examine the effect of fix interval on estimates of movement metrics. By calculating straight-line distances between locations taken at different fix intervals, we examined the rate of change in various metrics of caribou movement as a function of fix interval. We also calculated correction factors for different fix intervals, and examined how they changed seasonally. We fit an equation to the maximum rate of movement of caribou as a function of fix interval and used this equation in a modification of one screening algorithm to assess how it is affected by fix interval. We demonstrate how the maximum speed equation could potentially be used to derive a modified filter for telemetry data from highly mobile animals. Our results highlight the importance of incorporating fix-interval information into comparisons of movement metrics from different herds and time periods. © 2013 The Wildlife Society.

A new meteorite find, named Khatyrka, was recovered from eastern Siberia as a result of a search for naturally occurring quasicrystals. The meteorite occurs as clastic grains within postglacial clay-rich layers along the banks of a small stream in the Koryak Mountains, Chukotka Autonomous Okrug of far eastern Russia. Some of the grains are clearly chondritic and contain Type IA porphyritic olivine chondrules enclosed in matrices that have the characteristic platy olivine texture, matrix olivine composition, and mineralogy (olivine, pentlandite, nickel-rich iron-nickel metal, nepheline, and calcic pyroxene [diopside-hedenbergite solid solution]) of oxidized-subgroup CV3 chondrites. A few grains are fine-grained spinel-rich calcium-aluminum-rich inclusions with mineral oxygen isotopic compositions again typical of such objects in CV3 chondrites. The chondritic and CAI grains contain small fragments of metallic copper-aluminum-iron alloys that include the quasicrystalline phase icosahedrite. One grain is an achondritic intergrowth of Cu-Al metal alloys and forsteritic olivine ± diopsidic pyroxene, both of which have meteoritic (CV3-like) oxygen isotopic compositions. Finally, some grains consist almost entirely of metallic alloys of aluminum + copper ± iron. The Cu-Al-Fe metal alloys and the alloy-bearing achondrite clast are interpreted to be an accretionary component of what otherwise is a fairly normal CV3 (oxidized) chondrite. This association of CV3 chondritic grains with metallic copper-aluminum alloys makes Khatyrka a unique meteorite, perhaps best described as a complex CV3 (ox) breccia.

To provide a current overview of the epidemiology and pathophysiology of acute respiratory distress syndrome in adults and children, and to identify research questions that will address the differences between adults and children with acute respiratory distress syndrome.Narrative literature review and author-generated data.The epidemiology of acute respiratory distress syndrome in adults and children, lung morphogenesis, and postnatal lung growth and development are reviewed. The pathophysiology of acute respiratory distress syndrome is divided into eight categories: alveolar fluid transport, surfactant, innate immunity, apoptosis, coagulation, direct alveolar epithelial injury by bacterial products, ventilator-associated lung injury, and repair.Epidemiologic data suggest significant differences in the prevalence and mortality of acute respiratory distress syndrome between children and adults. Postnatal lung development continues through attainment of adult height, and there is overlap between the regulation of postnatal lung development and inflammatory, apoptotic, alveolar fluid clearance, and repair mechanisms. Therefore, there is a different biological baseline network of gene and protein expression in children as compared with adults.There are significant obstacles to performing research on children with acute respiratory distress syndrome. However, epidemiologic, clinical, and animal studies suggest age-dependent differences in the pathophysiology of acute respiratory distress syndrome. In order to reduce the prevalence and improve the outcome of patients with acute respiratory distress syndrome, translational studies of inflammatory, apoptotic, alveolar fluid clearance, and repair mechanisms are needed. Understanding the differences in pathophysiologic mechanisms in acute respiratory distress syndrome between children and adults should facilitate identification of novel therapeutic interventions to prevent or modulate lung injury and improve lung repair.