Fortified milk: a rare cause of intestinal obstruction in pre-term patients. / Leche fortificada: una causa infrecuente de obstrucción intestinal en pacientes prematuros.

INTRODUCTION: Intestinal obstruction secondary to the use of fortified milk is a rare cause in pre-term patients. CASE REPORT: We present the case of a female pre-term newborn admitted as a result of abdominal distension and rectal bleeding, which mimicked necrotizing enterocolitis. On abdominal X-ray, she had an obstruction pattern, and on ultrasonography, echogenic masses at the distal ileum were observed. Given the lack of improvement with conservative management, urgent exploratory laparotomy was decided upon. At surgery, compact milk masses at the level of the distal ileum were identified as the cause of intestinal obstruction. Appendicostomy and lavage with saline solution through the ileocecal valve were performed. This allowed milk masses to come out towards the colon, and a great amount of acholic stools to be expelled. CONCLUSION: The increase in "milk curd syndrome" cases should lead us to consider this cause in the differential diagnosis of intestinal obstruction in pre-term newborns fed with fortified milk.

INTRODUCCION: La obstrucción intestinal secundaria al uso de leche fortificada es una causa infrecuente descrita en pacientes prematuros. CASO CLINICO: Presentamos el caso de una recién nacida prematura que ingresa por distensión abdominal y rectorragia, simulando una enterocolitis necrotizante. En la radiografía abdominal presenta patrón obstructivo y en ecografía se identifican masas ecogénicas en íleon distal. Dada la no mejoría con manejo conservador, se decide laparotomía exploradora urgente. En la intervención se detectan masas compactas de leche a nivel de íleon distal como causa de la obstrucción intestinal. Se realiza apendicostomía y lavado con suero fisiológico a través de la válvula ileocecal, permitiendo salida de moldes hacia colon y expulsión de gran cantidad de heces acólicas. CONCLUSION: El repunte de casos de "milk curd syndrome" nos obliga a considerar esta causa en el diagnóstico diferencial de obstrucción intestinal en prematuros alimentados con leche fortificada.

Albendazole metabolites excretion in human saliva as a biomarker to assess treatment compliance in mass drug administration (MDA) anthelmintic programs.

Soil-transmitted-helminth (STH) infections continue to be a persistent global public health problem. Control strategies for STH have been based on the use of mass drug administration (MDA). Coverage and compliance assessment is critical to understanding the true effectiveness of albendazole (ABZ) in those MDA programs. The aims of this work were to characterize the pattern of albendazole and metabolites excretion in human saliva, and to develop a saliva-based biomarker (HPLC drug/metabolite detection) useful to accurately estimate the coverage/compliance in MDA campaigns. The study subjects were 12 healthy volunteers treated with a single oral dose of ABZ (400 mg). Saliva and blood (dried blood spot, DBS) samples were taken previously and between 2 and 72 h post-treatment. The samples were analyzed by HPLC with UV detection, C18 reversed-phase column. ABZ sulphoxide was the main analyte recovered up to 72 h p.t. in blood and saliva. The concentration profiles measured in the blood (DBS samples) were higher (P < 0.05) than those in saliva, however, this ABZ-metabolite was recovered longer in saliva. The in vivo measurement of drugs/metabolites in saliva samples from ABZ-treated volunteers offers strong scientific evidence to support the use of saliva as a valid biological sample for assessing compliance in MDA programs.

A new manual method for pork belly firmness measurement.

A new objective and standardized method for early determination of firmness of the intact pork belly in a research environment is described, and compared to the existing bar-bend method. The belly characteristics that contribute to the outcome of each method, and the relationship between the two methods are identified. •Original method requires a ribbed pork belly, and several minutes relaxation time.•New method provides an immediate measurement on an intact belly.•Advantages include early, rather than late, application in the fabrication process; rapid measurement; standardization; measurements minimally affected by animal length or belly length.

A new technique in the treatment of intestinal malrotation. / Una nueva técnica en el tratamiento de la malrotación intestinal.

INTRODUCTION: Intestinal malrotation is a congenital pathology with potentially catastrophic complications, such as volvulus, whose treatment has barely not changed in nearly 100 years (Ladd's procedure). Dr. Abu-Elmagd recently described a new technique that was applied in one of our patients. CLINICAL CASE: 12-year-old boy who had undergone Ladd's procedure as a result of intestinal volvulus secondary to malrotation when he was 2 days old. He had subocclusion and eventually obstruction, with intestinal volvulus compatible imaging. Intraoperative findings: duodenal subocclusion, volvulus and lymphangiectasias. Kareem's procedure: bowel positioning in normal rotation, duodenopexy (duodenal C posterior to the mesenteric vessels), formation of neo-Treitz, and fixation of the cecum, the ascending colon, and the mesenteric root. The patient was discharged on postoperative day 6 and remains asymptomatic after 1 year of follow-up. DISCUSSION: Kareem's procedure is a safe and effective malrotation repair technique. It can replace Ladd's procedure as it reduces the risk of re-volvulation and improves digestive symptoms.

INTRODUCCION: La malrotación intestinal es una patología congénita con complicaciones potencialmente catastróficas, destacando el vólvulo, cuyo tratamiento no ha variado significativamente en casi 100 años (procedimiento de Ladd). Recientemente el Dr. Abu-Elmagd describió una técnica que hemos aplicado en un paciente. CASO CLINICO: Varón de 12 años, intervenido con 2 días de vida por vólvulo intestinal secundario a malrotación realizándose procedimiento de Ladd. Presenta cuadros suboclusivos y finalmente obstructivo con imágenes compatibles con vólvulo intestinal. Hallazgos intraoperatorios: suboclusión duodenal, vólvulo y linfangiectasias. Procedimiento de Kareem: posicionando intestino en normorotación, duodenopexia (C duodenal posterior a vasos mesentéricos), formación de neoTreitz, fijación de ciego, colon ascendente y raíz mesentérica. Alta hospitalaria al 6º día postoperatorio, asintomático en 1 año de seguimiento. COMENTARIOS: El procedimiento de Kareem es una técnica segura y efectiva que corrige la malrotación, pudiendo reemplazar al procedimiento de Ladd al disminuir el riesgo de revolvulación y mejorar síntomas digestivos.

Developing an alternative classification method for predicting ham composition using linear measurements from the cross-sectional ham surface.

Digital image analysis based on the ham cross-sectional face was used to measure two lean muscle and three subcutaneous fat locations from 248 bone-in hams. Linear measurements of the two selected fat locations were used to predict dual-energy X-ray (DXA) fat or lean percentages with prediction accuracies (R2) of 0.7 in a stepwise regression eq. A classification system was built based on the prediction equations, and the linear measurements aimed to classify extremes at the threshold of the 10th percentile of DXA fat percentage (> 32.0%) and lean percentage (< 60.2%). When using either DXA fat or lean percentage, lean ham prediction accuracy dropped by 18%, but fat ham prediction accuracy increased by 60% when the threshold was changed from the 10th percentile to the 30th percentile. This classification approach has the potential to be converted into a manual tool with several useful applications for commercial pork processors.

Evaluating the effect of temperature and multiple bends on an automated pork belly firmness conveyor belt classification system.

Skin-on, and bone-in bellies (n = 94) were cut into Canadian specifications and assessed on an automated conveyor belt system based on different levels of firmness. Temperature settings at 4 °C, 2 °C, and - 1.5 °C had significant effect (P < 0.05) on the bending angle, after 24 cm of the belly had passed the nosebar. The stepwise regression relationship had R2 âˆ¼ 0.18-0.67 between iodine value and bending angle at all temperatures. Bending bellies multiple times changed firmness classification of bellies at 4 and 2 °C, but bend number did not influence firmness classification at -1.5 °C. The automated conveyer belt system presented the potential to classify pork bellies based on firmness for industrial applications.

Mars 2020 Perseverance Rover Studies of the Martian Atmosphere Over Jezero From Pressure Measurements.

The pressure sensors on Mars rover Perseverance measure the pressure field in the Jezero crater on regular hourly basis starting in sol 15 after landing. The present study extends up to sol 460 encompassing the range of solar longitudes from L s  âˆ¼ 13°-241° (Martian Year (MY) 36). The data show the changing daily pressure cycle, the sol-to-sol seasonal evolution of the mean pressure field driven by the CO2 sublimation and deposition cycle at the poles, the characterization of up to six components of the atmospheric tides and their relationship to dust content in the atmosphere. They also show the presence of wave disturbances with periods 2-5 sols, exploring their baroclinic nature, short period oscillations (mainly at night-time) in the range 8-24 min that we interpret as internal gravity waves, transient pressure drops with duration ∼1-150 s produced by vortices, and rapid turbulent fluctuations. We also analyze the effects on pressure measurements produced by a regional dust storm over Jezero at L s  âˆ¼ 155°.

Long-Term Monitoring of Aphid-Transmitted Viruses in Melon and Zucchini Crops: Genetic Diversity and Population Structure of Cucurbit Aphid-Borne Yellows Virus and Watermelon Mosaic Virus.

Understanding the emergence and prevalence of viral diseases in crops requires the systematic epidemiological monitoring of viruses, as well as the analysis of how ecological and evolutionary processes combine to shape viral population dynamics. Here, we extensively monitored the occurrence of six aphid-transmitted viruses in melon and zucchini crops in Spain for 10 consecutive cropping seasons between 2011 and 2020. The most prevalent viruses were cucurbit aphid-borne yellows virus (CABYV) and watermelon mosaic virus (WMV), found in 31 and 26% of samples with yellowing and mosaic symptoms. Other viruses, such as zucchini yellow mosaic virus, cucumber mosaic virus, Moroccan watermelon mosaic virus, and papaya ring spot virus, were detected less frequently (<3%) and mostly in mixed infections. Notably, our statistical analysis showed a significant association between CABYV and WMV in melon and zucchini hosts, suggesting that mixed infections might be influencing the evolutionary epidemiology of these viral diseases. We then carried out a comprehensive genetic characterization of the full-length genome sequences from CABYV and WMV isolates by using the Pacific Biosciences single-molecule real-time (PacBio) high-throughput technology to assess the genetic variation and structure of their populations. Our results showed that the CABYV population displayed seven codons under positive selection, and although most isolates clustered in the Mediterranean clade, a subsequent analysis of molecular variance revealed a significant, fine-scale temporal structure, which was in part explained by the level of the variance between isolates from single and mixed infections. In contrast, the WMV population genetic analysis showed that most of the isolates grouped into the Emergent clade, with no genetic differentiation and under purifying selection. These results underlie the epidemiological relevance of mixed infections for CABYV and provide a link between genetic diversity and CABYV dynamics at the whole-genome level.

[Mpox and pregnancy: A neglected disease and its impact on perinatal health]. / La viruela del mono y el embarazo: una enfermedad olvidada y su impacto en la salud perinatal.

Viral infections during pregnancy have been one of the leading causes associated with significant perinatal problems, such as congenital defects, fetal neurological syndromes, stillbirths, and adverse pregnancy outcomes. The mpox virus infection, caused by an Orthopoxvirus related to the human smallpox virus, was declared a global health emergency by the World Health Organization in July 2022 due to the large number of cases emerging outside the usual endemic area in Africa. There is little information on the impact of mpox virus infection during pregnancy, although the limited evidence available shows a high rate of fetal harm. This review addresses the problem of mpox virus infection in pregnant women and provides indications for its prevention, diagnosis, and treatment.

Mpox and pregnancy: A neglected disease and its impact on perinatal health.

Viral infections during pregnancy have been one of the leading causes associated with significant perinatal problems, such as congenital defects, fetal neurological syndromes, stillbirths, and adverse pregnancy outcomes. The mpox virus infection, caused by an Orthopoxvirus related to the human smallpox virus, was declared a global health emergency by the World Health Organization in July 2022 due to the large number of cases emerging outside the usual endemic area in Africa. There is little information on the impact of mpox virus infection during pregnancy, although the limited evidence available shows a high rate of fetal harm. This review addresses the problem of mpox virus infection in pregnant women and provides indications for its prevention, diagnosis, and treatment.

The sound of a Martian dust devil.

Dust devils (convective vortices loaded with dust) are common at the surface of Mars, particularly at Jezero crater, the landing site of the Perseverance rover. They are indicators of atmospheric turbulence and are an important lifting mechanism for the Martian dust cycle. Improving our understanding of dust lifting and atmospheric transport is key for accurate simulation of the dust cycle and for the prediction of dust storms, in addition to being important for future space exploration as grain impacts are implicated in the degradation of hardware on the surface of Mars. Here we describe the sound of a Martian dust devil as recorded by the SuperCam instrument on the Perseverance rover. The dust devil encounter was also simultaneously imaged by the Perseverance rover's Navigation Camera and observed by several sensors in the Mars Environmental Dynamics Analyzer instrument. Combining these unique multi-sensorial data with modelling, we show that the dust devil was around 25 m large, at least 118 m tall, and passed directly over the rover travelling at approximately 5 m s-1. Acoustic signals of grain impacts recorded during the vortex encounter provide quantitative information about the number density of particles in the vortex. The sound of a Martian dust devil was inaccessible until SuperCam microphone recordings. This chance dust devil encounter demonstrates the potential of acoustic data for resolving the rapid wind structure of the Martian atmosphere and for directly quantifying wind-blown grain fluxes on Mars.

Dust, Sand, and Winds Within an Active Martian Storm in Jezero Crater.

Rovers and landers on Mars have experienced local, regional, and planetary-scale dust storms. However, in situ documentation of active lifting within storms has remained elusive. Over 5-11 January 2022 (LS 153°-156°), a dust storm passed over the Perseverance rover site. Peak visible optical depth was ∼2, and visibility across the crater was briefly reduced. Pressure amplitudes and temperatures responded to the storm. Winds up to 20 m s-1 rotated around the site before the wind sensor was damaged. The rover imaged 21 dust-lifting events-gusts and dust devils-in one 25-min period, and at least three events mobilized sediment near the rover. Rover tracks and drill cuttings were extensively modified, and debris was moved onto the rover deck. Migration of small ripples was seen, but there was no large-scale change in undisturbed areas. This work presents an overview of observations and initial results from the study of the storm.

Hexagonal Prisms Form in Water-Ice Clouds on Mars, Producing Halo Displays Seen by Perseverance Rover.

Observations by several cameras on the Perseverance rover showed a 22° scattering halo around the Sun over several hours during northern midsummer (solar longitude 142°). Such a halo has not previously been seen beyond Earth. The halo occurred during the aphelion cloud belt season and the cloudiest time yet observed from the Perseverance site. The halo required crystalline water-ice cloud particles in the form of hexagonal columns large enough for refraction to be significant, at least 11 µm in diameter and length. From a possible 40-50 km altitude, and over the 3.3 hr duration of the halo, particles could have fallen 3-12 km, causing downward transport of water and dust. Halo-forming clouds are likely rare due to the high supersaturation of water that is required but may be more common in northern subtropical regions during northern midsummer.

Classical harmonic three-body system: an experimental electronic realization.

The classical three-body harmonic system in [Formula: see text] ([Formula: see text]) with finite rest lengths and zero total angular momentum [Formula: see text] is considered. This model describes the dynamics of the [Formula: see text] near-equilibrium configurations of three point masses [Formula: see text] with arbitrary pairwise potential [Formula: see text] that solely depends on the relative distances between bodies. It exhibits an interesting mixed regular and chaotic dynamics as a function of the energy and the system parameters. The corresponding harmonic quantum system plays a fundamental role in atomic and molecular physics. In this work we report on a novel electronic experimental realization of the model as a complementary tool to analyze the rich dynamics of the classical system. Our setup allows us to experimentally explore different regions of behavior due to the fact that the intrinsic parameters and initial states of the system are independently set by voltage inputs. Chaotic and periodic motions are characterized employing time series, phase planes, and the largest Lyapunov exponents as a function of the energy and system parameters. The results show an excellent qualitative as well as quantitative agreement between theory and experiment.

In situ recording of Mars soundscape.

Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat1, (2) the speed of sound varies at the surface with frequency2,3 and (3) high-frequency waves are strongly attenuated with distance in CO2 (refs. 2-4). However, theoretical models were uncertain because of a lack of experimental data at low pressure and the difficulty to characterize turbulence or attenuation in a closed environment. Here, using Perseverance microphone recordings, we present the first characterization of the acoustic environment on Mars and pressure fluctuations in the audible range and beyond, from 20 Hz to 50 kHz. We find that atmospheric sounds extend measurements of pressure variations down to 1,000 times smaller scales than ever observed before, showing a dissipative regime extending over five orders of magnitude in energy. Using point sources of sound (Ingenuity rotorcraft, laser-induced sparks), we highlight two distinct values for the speed of sound that are about 10 m s-1 apart below and above 240 Hz, a unique characteristic of low-pressure CO2-dominated atmosphere. We also provide the acoustic attenuation with distance above 2 kHz, allowing us to explain the large contribution of the CO2 vibrational relaxation in the audible range. These results establish a ground truth for the modelling of acoustic processes, which is critical for studies in atmospheres such as those of Mars and Venus.

Impacto del COVID-19 en la circulación de virus respiratorios en un hospital pediátrico: una ausencia esperada / Impact of COVID-19 on the circulation of respiratory viruses in a children's hospital: an expected absence

Introducción. Los virus respiratorios son la principal causa de infección respiratoria aguda baja (IRAB) en la población pediátrica. En marzo de 2020, la Organización Mundial de la Salud declaró el estado de pandemia de la enfermedad por el nuevo coronavirus 2019 (COVID-19) con un impacto global elevado. El objetivo de este estudio fue describir el impacto de la pandemia de COVID-19 en las internaciones por IRAB en el Hospital de Niños Ricardo Gutiérrez (HNRG) y la circulación viral. Métodos. Estudio observacional, retrospectivo y descriptivo de pacientes internados por IRAB, comparando los años 2019 y 2020. Resultados. En 2020, la tasa de hospitalización por IRAB se redujo un 73 % en el HNRG (575,1/10 000 en 2019 y 155,3/10 000 en 2020). En 2019 se internaron 517 pacientes con IRAB; en 174 se identificaron los virus: sincicial respiratorio (71,2 %), adenovirus (AV) (10,3%), parainfluenza (PIF) (9,7 %) e influenza (FLU) (8,6 %). En 2020, se hospitalizaron 94 pacientes con IRAB. Hasta la semana epidemiológica (SE) 13 se registraron casos de IRAB por PIF y AV; en la SE 29 un caso de bronquiolitis por AV y rinovirus (RV), seguido de casos aislados de RV; no hubo IRAB por VSR ni por FLU. Se registraron 9 casos de IRAB por COVID-19: 2 bronquiolitis moderadas y 7 neumonías focales; con un adolescente fallecido por neumonía por COVID-19 con comorbilidades. En 2020, los casos presentaron mayor edad, más comorbilidades e internaciones previas en comparación con el 2019. La neumonía focal fue la presentación clínica predominante. Conclusión. En 2020, la tasa de hospitalización por IRAB se redujo significativamente en comparación con el año anterior, con ausencia de circulación de virus respiratorios estacionales en la población asistida en nuestro centro.

Introduction. Respiratory viruses are the main cause of acute lower respiratory tract infection (ALRTI) in the pediatric population. In March 2020, the World Health Organization declared that the new coronavirus disease 2019 (COVID-19) had reached the pandemic status. Our objective was to describe the impact of COVID-19 pandemic on hospitalizations due to ALRTI at Hospital de Niños Ricardo Gutiérrez (HNRG) and virus circulation. Methods. Observational, retrospective, and descriptive study of patients hospitalized due to ALRTI comparing 2019 and 2020. Results. In 2020, the rate of hospitalization due to ALRTI decreased by 73%. In 2019, 517 patients with ALRTI were hospitalized; the following viruses were identified in 174: respiratory syncytial virus (RSV) (71.2%), adenovirus (AV) (10.3%), parainfluenza virus (PIV) (9.7%), and influenza virus (FLU) (8.6%). In 2020, 94 patients with ALRTI were hospitalized. Until epidemiological week (EW) 13, cases of ALRTI due to PIV and AV were recorded; in EW 29, there was 1 case of bronchiolitis due to AV and rhinovirus (RV), followed by isolated cases of RV; no ALRTI due to RSV or FLU was recorded. In total, 9 cases of ALRTI due to COVID-19 were recorded: 2 moderate bronchiolitis and 7 focal pneumonia; 1 adolescent with comorbidities died due to COVID-19 pneumonia. In 2020, patients were older and had more comorbidities and prior hospitalizations compared to 2019. Focal pneumonia prevailed. Conclusion. In 2020, the rate of hospitalization due to ALRTI decreased significantly compared to 2019,with the absence of seasonal respiratory virus circulation in the pediatric population.

Impact of COVID-19 on the circulation of respiratory viruses in a children's hospital: an expected absence. / Impacto del COVID-19 en la circulación de virus respiratorios en un hospital pediátrico: una ausencia esperada.

INTRODUCTION: Respiratory viruses are the main cause of acute lower respiratory tract infection (ALRTI) in the pediatric population. In March 2020, the World Health Organization declared that the new coronavirus disease 2019 (COVID-19) had reached the pandemic status. Our objective was to describe the impact of COVID-19 pandemic on hospitalizations due to ALRTI at Hospital de Niños Ricardo Gutiérrez (HNRG) and virus circulation. METHODS: Observational, retrospective, and descriptive study of patients hospitalized due to ALRTI comparing 2019 and 2020. RESULTS: In 2020, the rate of hospitalization due to ALRTI decreased by 73%. In 2019, 517 patients with ALRTI were hospitalized; the following viruses were identified in 174: respiratory syncytial virus (RSV) (71.2%), adenovirus (AV) (10.3%), parainfluenza virus (PIV) (9.7%), and influenza virus (FLU) (8.6%). In 2020, 94 patients with ALRTI were hospitalized. Until epidemiological week (EW) 13, cases of ALRTI due to PIV and AV were recorded; in EW 29, there was 1 case of bronchiolitis due to AV and rhinovirus (RV), followed by isolated cases of RV; no ALRTI due to RSV or FLU was recorded. In total, 9 cases of ALRTI due to COVID-19 were recorded: 2 moderate bronchiolitis and 7 focal pneumonia; 1 adolescent with comorbidities died due to COVID-19 pneumonia. In 2020, patients were older and had more comorbidities and prior hospitalizations compared to 2019. Focal pneumonia prevailed. CONCLUSIONS: In 2020, the rate of hospitalization due to ALRTI decreased significantly compared to 2019, with the absence of seasonal respiratory virus circulation in the pediatric population.

Introducción. Los virus respiratorios son la principal causa de infección respiratoria aguda baja (IRAB) en la población pediátrica. En marzo de 2020, la Organización Mundial de la Salud declaró el estado de pandemia de la enfermedad por el nuevo coronavirus 2019 (COVID-19) con un impacto global elevado. El objetivo de este estudio fue describir el impacto de la pandemia de COVID-19 en las internaciones por IRAB en el Hospital de Niños Ricardo Gutiérrez (HNRG) y la circulación viral. Métodos. Estudio observacional, retrospectivo y descriptivo de pacientes internados por IRAB, comparando los años 2019 y 2020. Resultados. En 2020, la tasa de hospitalización por IRAB se redujo un 73 % en el HNRG (575,1/10 000 en 2019 y 155,3/10 000 en 2020). En 2019 se internaron 517 pacientes con IRAB; en 174 se identificaron los virus: sincicial respiratorio (71,2%), adenovirus (AV) (10,3%), parainfluenza (PIF) (9,7 %) e influenza (FLU) (8,6 %). En 2020, se hospitalizaron 94 pacientes con IRAB. Hasta la semana epidemiológica (SE) 13 se registraron casos de IRAB por PIF y AV; en la SE 29 un caso de bronquiolitis por AV y rinovirus (RV), seguido de casos aislados de RV; no hubo IRAB por VSR ni por FLU. Se registraron 9 casos de IRAB por COVID-19: 2 bronquiolitis moderadas y 7 neumonías focales; con un adolescente fallecido por neumonía por COVID-19 con comorbilidades. En 2020, los casos presentaron mayor edad, más comorbilidades e internaciones previas en comparación con el 2019. La neumonía focal fue la presentación clínica predominante. Conclusión. En 2020, la tasa de hospitalización por IRAB se redujo significativamente en comparación con el año anterior, con ausencia de circulación de virus respiratorios estacionales en la población asistida en nuestro centro.

Chemotaxonomy of Five South American Species of the Triatoma genus (Hemiptera: Reduviidae: Triatominae) Based on Their Cuticle Hydrocarbon Pattern.

The Triatoma sordida subcomplex traditionally included four triatomine species, T. sordida, Triatoma garciabesi, Triatoma guasayana, and Triatoma patagonica, distributed in the Southern Cone of South America. These species have a large intraspecific variability together with an overall similarity, making difficult to establish their taxonomic status. Many cytogenetic, morphometric, and molecular markers have been applied to address this. Recent studies have posed concerns on the inclusion of T. guasayana and T. patagonica within the subcomplex. Also, T. sordida from Argentina has been designed as a new species, Triatoma rosai. Using the cuticular hydrocarbon pattern as chemotaxonomic marker, the relationships among several populations of these species were analyzed by capillary gas chromatography and linear discriminant analysis along 25 collection sites in Argentina, Bolivia, Brazil, and Paraguay. T. sordida and T. rosai populations were differentially clustered in two CHC-based groups: "Group 1" included T. sordida from Eastern Brazil, Eastern Paraguay, and the Bolivian populations from La Paz and Izozog G1; "Group 2" included T. rosai, and T. sordida from Izozog G2 (Bolivia), and Western Paraguay. Whereas T. garciabesi remained closely related to T. sordida and T. rosai, T. guasayana, and T. patagonica were clearly separated from the species of the T. sordida subcomplex. Our results agree with those from other several techniques suggesting that the taxonomy of the T. sordida subcomplex should be revised.

The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission.

NASA's Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.