Microsatellite Constellation for Mars Communication and Navigation

Exploration of Mars and establishment of human settlement have been of sharp interest for several decades. Since the turn of the century, efforts have been ramped up to make these a reality. With the execution of multiple robotic exploration missions and several more planned missions in the next two decades, as well as serious plans for human landing missions, a key need is the establishment of accurate, reliable, expansive, and cost-effective positioning and communication service for several users in the Mars environment. The Mars Communication and Navigation (MCN) mission is a multi-satellite constellation at Mars that shall provide data relay and positioning services for the identified possible users, that are orbiters, landers, ascenders, autonomous rovers, and human landing missions. The aim of MCN is to investigate and prototype key technologies for a Mars positioning and communication system using small satellites, in order to enable the development and operations of a wide range of Mars missions, providing a backbone Earth–Mars communication and navigation infrastructure. This work focuses on the critical architectural aspects of the MCN. The end-to-end (E2E) system architecture is presented, in order to provide an overview of the space and ground segments along with the operations concepts. Concerning the orbital configuration, the constellation and its deployment strategy are discussed. The MCN constellation baseline comprises 24 microsatellites operating in a Walker-like orbital configuration at Mars to provide service for more than 70 users potentially. Moreover, a Relay/Gateway link is utilized to serve as a communication bridge between Earth ground segment and the MCN constellation. Concerning the communication and navigation aspects, their architectures and possible solutions are highlighted, together with an overview of the related critical technologies required to achieve the mission objectives

LongITools: Dynamic longitudinal exposome trajectories in cardiovascular and metabolic noncommunicable diseases

The current epidemics of cardiovascular and metabolic noncommunicable diseases have emerged alongside dramatic modifications in lifestyle and living environments. These correspond to changes in our “modern” postwar societies globally characterized by rural-to-urban migration, modernization of agricultural practices, and transportation, climate change, and aging. Evidence suggests that these changes are related to each other, although the social and biological mechanisms as well as their interactions have yet to be uncovered. LongITools, as one of the 9 projects included in the European Human Exposome Network, will tackle this environmental health equation linking multidimensional environmental exposures to the occurrence of cardiovascular and metabolic noncommunicable diseases.</p

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

Peer reviewe

Rapid assessment of hearth and lung with a smartphone size hand held ultrasound machine in critical patients to enhance and complement the pysical examination

Transthoracic high-end standard echocardiography (SE) is an integral part of cardiologic critical patient (pts) assessment. The newest generation of smartphone-size hand held ultrasound devices (echoPod) enables bedside TTE with 2D imaging and colour-Doppler. The aim of the present preliminary study was to evaluate the diagnostic value of echoPod in critical cardiologic pts. Methods. 132 consecutive pts (64 STEMI, 44 NSTEMI, 4 pericardial effusion, 6 pulmonary embolism, 10 arrhythmias, 4 intra-aortic balloon pump counterpulsated shocks) immediately after admitted in ICCU underwent examinations with a echoPod (VSCAN). Within 2 hours 20 pts underwent SE to compare the diagnostic ability of echoPod in critically ill patients. Target parameters were global systolic left-ventricular function (LVF, normal >55% or severely-impaired <30%), identification of marked right and/or left ventricular enlargement (RVE, LVE, yes/no), identification of left wall motion abnormalities LWMA), presence of severe valvular regurgitation (sev REG, yes/no), evidence of pericardial effusion (PE yes/no), of pleural effusion (PluE yes/no) and identification of comets lung (CL, yes/no). Results. 100% concordance was found in semi-quantitative assessment of LVF, RVE, LVE, PE, PluE, CL. Good concordance (>95%) was found for identification of sevREG. LWMA were correctly identified by echoPod with a sensitivity of 78% (95%CI 0.4-0.98) and a specificity of 100% (95% CI 0.89-1). Conclusion. A smartphone-size hand held ultrasound device permits reliable and quick assessment of RV and LV dimension and function. Largest differences were found for identification of LWMA. Severe Regurgitations and pericardial effusion can be well identified by echoPod too. Besides the echoPod can be also used in lung analysis particularly in pleural effusion and “comets” detection. An echoPod exam does not replace the standard echocardiographic exam, but can provide a rapid bedside pre-assessment which may help to improve patient management and to optimize the individual diagnostic work-flow in several clinical scenario like emergency room or ambulance for example

Developing mentorship in clinical practice:psychometrics properties of the Mentors’ Competence Instrument

Abstract Clinical placements are an important part of nursing education to developing nursing students’ competencies. In enhancing clinical learning, to focus on mentors’ competences is pivotal as they are the main role models and experts in guiding. This study is validated the Italian version of the Mentors’ Competence Instrument. A sampling frame of 648 mentors was involved. The final sample included 291 mentors (response rate 45%). Confirmatory Factor Analysis was performed. Fit indices were also calculated to evaluate validity. The scale demonstrated optimal fit indexes and its validity was confirmed by psychometrical testing. In detail, Root Mean Square Error of Approximation is 0.058, Standardized Root Mean Residual is 0.046, Comparative Fit Index is 0.893 and Tucker-Lewis Index 0.886. Cronbach’s alpha ranges from 0.77 to 0.95 among factors. This is the first validation of the scale performed in a different country from the original study. The performed psychometric testing showed that the scale is valid and reliable, as well as consistent with the theoretical structure reported for a different national context. This scale can be beneficial for comparing mentors’ competencies across different clinical learning environments and could be used to build a broader model of mentors’ competencies

Role of mixed venous oxygen saturation in patients developing cardiogenic shock after ST elevation myocardial infarction (STEMI) treated with inotropic therapy

Background. Low mixed venous saturation (SvO2) can reveal global tissue hypoxia and therefore can predict an increase of myocardial oxygen consumption (MvO2) and a poor prognosis in patients with cardiogenicshock after ST elevation myocardial infarction (STEMI). Early goal directed therapy, aiming to an SvO2 ≥70%, has been shown to be a valuable strategy in patients with a low output syndrome. Aim. The aim of this retrospective study was to determine the agreement between SvO2 and early hemodynamic status of patients with cardiogenic shock after STEMI. Methods. During the observation period (16-months), 79 patients were admitted in our ICU for cardiogenic shock after STEMI; patients who required an intra-aortic balloon pump (n=15) and/or mechanical ventilation (n=21) were excluded from the analysis. The hemodynamic management of studied patients was based on guideline treatment, and to maintain individual cardiac index and mixed venous oxygen saturation between 1.5 and 2.7 L/min/m2 and 55 and 65%, respectively, all patients were treated with an inotropic agent (dobutamine or levosimendan). Heart rate (HR), arterial blood pressure (ABP), central venous pressure (CVP), SvO2, pulmonary artery pressure (PAP), lactate plasma levels (LAC) and cardiac index (CI) were recorded for 24.2±2.9 hours. To optimize systemic afterload and coronary perfusion, mean arterial blood pressure (MAP) was individually maintained between 50 and 75 mmHg using sodium nitroprusside to decrease or norepinephrine to increase systemic vascular resistances, as clinically indicated. Results. In the Dobutamine group (n=24) the mean SvO2 value was 68.2±11.8% with mean CVP of 13.0±4.9 mmHg, LAC of 6.3±4.2 mmol/l and APACHE II score of 21.7±7.3; in-hospital mortality in this group was 32.0%. The Levosimendan group (n=19) showed a CVP of 13.7±4.6 mmHg, mean ScvO2 values of 78.6±10.2%, LAC of 3.3±2.3 mmol/l and APACHE II score of 22.2±5.4; in-hospital mortality in this group was 28.0%. Conclusions. SvO2 , in our study, was significantly (p<0.001) lower in dobutamine group (68.2±11.8%) compared to levosimendan group (78.6±10.2%); this difference correlated with an increase in oxygen consumption and extraction ratio, and it is associated with a negative metabolic effect

Role of passive leg raising to evaluate preload responsiveness in patients with cardiogenic shock after ST elevation myocardial infarction (STEMI) treated with inotropic therapy

Background. Optimal cardiac filling is essential for maintaining an adequate cardiac output and organ perfusion in patients with cardiogenic shock (CS) after ST elevation myocardial infarction (STEMI). “Static” hemodynamic parameters including central venous pressure (CVP) and pulmonary artery occlusion pressure (PAOP) have been used to estimate preload, although their predictive value on fluid responsiveness is not accurate in the presence of huge variations of intrathoracic pressure. Passive leg raising (PLR) represents a “self-volume challenge” that could predict fluid response; the transient hemodynamic effect of PLR on left ventricular stroke volume (SV) detect preload responsiveness in patients with CS after STEMI. Hemodynamic stabilization, preload optimization and correct management of inotropic and fluid therapy is of utmost importance in this patients with a low output syndrome. Aim. The aim of this retrospective study was to determine the agreement between PLR and early hemodynamic status of patients with CS after STEMI. Methods. During observation period (16-months), 79 patients were admitted in our ICU for CS after STEMI; patients who required an intraaortic balloon pump (n=15) and/or mechanical ventilation (n=21) and which were not monitored with PiCCO (n=31) were excluded from the analysis. The final pool included in the study was 12 patients. The hemodynamic management of studied patients was based on guideline treatment, and to maintain individual cardiac index between 1.5 and 2.7 L/min/m2, all patients were treated with an inotropic agent. Heart rate (HR), arterial blood pressure (ABP), CVP, PAOP, lactate plasma levels (LAC), SV, intrathoracic blood volume (ITBV), global end- iastolic volume (GEDV), were recorded in a supine position (baseline position) and after patients were in a supine position with the lower limbs elevated 30° to 45°. Each hemodynamic measurement was recorded within the first 5 min. Patients were considered as fluid preload responsiveness if PLR induced SV increased by ≥10%. To optimize systemic afterload and coronary perfusion, mean arterial blood pressure (MAP) was individually maintained between 60 and 75 mmHg using sodium nitroprusside to decrease vascular resistances, or detect preload responsiveness with PLR. When the MAP was lower 60 mmHg. if the patient was nonresponder was used norepinephrine to increase systemic, as clinically indicated. We measured SV using PiCCO monitor, we calculated changes in SV, induced by PLR. Among 12 patients included in this study, 5 had a SV increase of >10% after PLR. Results. In the responders group (n=5) SV was significantly increased by PLR from 47±14 to 50±14 mL (p<0.001). In these patients infusion within 15 min by 100 mL of 6% hydroxyethyl starch (Voluven) increased SV from 47±14 to 53±15 mL (p<0.001). In the non responders group (n=7) SV has not significantly increased by PLR, from 42±12 to 45±11 mL. In these patients volume expansion increased SV of 45±14 mL. Conclusions. Changes in SV and radial pulse pressure induced by PLR are accurate and interchangeable indices for predicting fluid responsiveness in patients with CS after STEMI

Non invasive ventilation for cardiogenic pulmunary edema in ICCU: froth and bubbles

Background. Respiratory failure associated with acute cardiogenic pulmonary edema (ACPE) characterizes an important subgroup of patients with treatment difficulties. These patients when receiving noninvasive positive pressure ventilation (NPPV) via helmet, experienced more effective output with respect to the single therapy. Objectives. To evaluate the clinical application of NPPV in ACPE complicated by respiratory effort (RE) hospitalized in ICCU. Population. From January to June 2010, 28 ACPE complicated by RE have been treated with medical therapy and NPPV via helmet. RE is defined by a D-pCO2 >2 mmHg value at the entry. D-pCO2 is the difference between pCO2 measured and awaited (pCO2 awaited = 1.5*HCO3+8). Intervention. The helmet is made of transparent latex-free PVC. The helmet is secured by two armpit breces at two hooks on the metallic ring that joins the helmet with a soft collar. The pressure increase during ventilation makes the soft collar seal comfortably to the neck and the shoulders, avoiding air leakage. The two ports of the helmet act as inlet and outlet of the gas flow. the inspiratory and expiratory valves are those of mechanical ventilator. Patients with cardiogenic shock, chronic respiratory failure (CRF), anaemia, and other not cardiac causes of dyspnea have been excluded. Initial ventilatory settings were continuous positive airway pressure (CPAP) mode, 5 cm H2O, with pressure support ventilation of 10 to 20 cm H2O titrated to achieve a respiratory rate less than 25 breaths/min and an exhaled tidal volume of 7 mL/kg or more. Ventilator settings were adjusted following arterial blood gases (ABG) results. Results. Failure to improve ABG values was the reason for ETI in 2 patients (7%). One patient has died during treatment (3.5%). two patients did not tolerate the helmet (7%). No complications developed for the use of the helmet.The average duration of NPPV was 27±12 h. After 12 hours of the NINV in these patients has determined an improvement of the cardiac frequency from 109±16 to 81±12 (p=0.002), respiratory frequency from 38±6 to 19±3 (p=0.002). Arterial blood saturation increased from 74%±14 to 96%±5 (p<0.0001), pH from 7.21±0.10 to 7.40±0.09 (p=0.001), pO2 from 52±16 to 100±31 (p<0.001) as well, while pCO2 decreased from 66±17 to 41±10 (p=0.02).Significant variations of systolic and diastolic blood pressure where not reported. Conclusions. In patients with acute cardiogenic pulmonary edema, noninvasive ventilation induces a more rapid improvement in respiratory distress and metabolic disturbance than does standard oxygen therapy, has no effect on short-term mortality. The application of NPPV in clinical practice in ICCU is a cardiologist’s effective and safe alternative to ETI for a patients affected by respiratory failure associated with ACPE. 158S