A review of the in situ probe designs from recent Ice Giant mission concept studies.

For the Ice Giants, atmospheric entry probes provide critical measurements not attainable via remote observations. Including the 2013-2022 NASA Planetary Decadal Survey, there have been at least five comprehensive atmospheric probe engineering design studies performed in recent years by NASA and ESA. International science definition teams have assessed the science requirements, and each recommended similar measurements and payloads to meet science goals with current instrument technology. The probe system concept has matured and converged on general design parameters that indicate the probe would include a 1-meter class aeroshell and have a mass around 350 to 400-kg. Probe battery sizes vary, depending on the duration of a post-release coast phase, and assumptions about heaters and instrument power needs. The various mission concepts demonstrate the need for advanced power and thermal protection system development. The many completed studies show an Ice Giant mission with an in situ probe is feasible and would be welcomed by the international science community.

Juno observations of spot structures and a split tail in Io-induced aurorae on Jupiter.

Jupiter's aurorae are produced in its upper atmosphere when incoming high-energy electrons precipitate along the planet's magnetic field lines. A northern and a southern main auroral oval are visible, surrounded by small emission features associated with the Galilean moons. We present infrared observations, obtained with the Juno spacecraft, showing that in the case of Io, this emission exhibits a swirling pattern that is similar in appearance to a von Kármán vortex street. Well downstream of the main auroral spots, the extended tail is split in two. Both of Ganymede's footprints also appear as a pair of emission features, which may provide a remote measure of Ganymede's magnetosphere. These features suggest that the magnetohydrodynamic interaction between Jupiter and its moon is more complex than previously anticipated.

Clusters of cyclones encircling Jupiter's poles.

The familiar axisymmetric zones and belts that characterize Jupiter's weather system at lower latitudes give way to pervasive cyclonic activity at higher latitudes. Two-dimensional turbulence in combination with the Coriolis ß-effect (that is, the large meridionally varying Coriolis force on the giant planets of the Solar System) produces alternating zonal flows. The zonal flows weaken with rising latitude so that a transition between equatorial jets and polar turbulence on Jupiter can occur. Simulations with shallow-water models of giant planets support this transition by producing both alternating flows near the equator and circumpolar cyclones near the poles. Jovian polar regions are not visible from Earth owing to Jupiter's low axial tilt, and were poorly characterized by previous missions because the trajectories of these missions did not venture far from Jupiter's equatorial plane. Here we report that visible and infrared images obtained from above each pole by the Juno spacecraft during its first five orbits reveal persistent polygonal patterns of large cyclones. In the north, eight circumpolar cyclones are observed about a single polar cyclone; in the south, one polar cyclone is encircled by five circumpolar cyclones. Cyclonic circulation is established via time-lapse imagery obtained over intervals ranging from 20 minutes to 4 hours. Although migration of cyclones towards the pole might be expected as a consequence of the Coriolis ß-effect, by which cyclonic vortices naturally drift towards the rotational pole, the configuration of the cyclones is without precedent on other planets (including Saturn's polar hexagonal features). The manner in which the cyclones persist without merging and the process by which they evolve to their current configuration are unknown.

Ammoniated phyllosilicates with a likely outer Solar System origin on (1) Ceres.

Studies of the dwarf planet (1) Ceres using ground-based and orbiting telescopes have concluded that its closest meteoritic analogues are the volatile-rich CI and CM carbonaceous chondrites. Water in clay minerals, ammoniated phyllosilicates, or a mixture of Mg(OH)2 (brucite), Mg2CO3 and iron-rich serpentine have all been proposed to exist on the surface. In particular, brucite has been suggested from analysis of the mid-infrared spectrum of Ceres. But the lack of spectral data across telluric absorption bands in the wavelength region 2.5 to 2.9 micrometres--where the OH stretching vibration and the H2O bending overtone are found--has precluded definitive identifications. In addition, water vapour around Ceres has recently been reported, possibly originating from localized sources. Here we report spectra of Ceres from 0.4 to 5 micrometres acquired at distances from ~82,000 to 4,300 kilometres from the surface. Our measurements indicate widespread ammoniated phyllosilicates across the surface, but no detectable water ice. Ammonia, accreted either as organic matter or as ice, may have reacted with phyllosilicates on Ceres during differentiation. This suggests that material from the outer Solar System was incorporated into Ceres, either during its formation at great heliocentric distance or by incorporation of material transported into the main asteroid belt.

Dark material on Vesta from the infall of carbonaceous volatile-rich material.

Localized dark and bright materials, often with extremely different albedos, were recently found on Vesta's surface. The range of albedos is among the largest observed on Solar System rocky bodies. These dark materials, often associated with craters, appear in ejecta and crater walls, and their pyroxene absorption strengths are correlated with material brightness. It was tentatively suggested that the dark material on Vesta could be either exogenic, from carbon-rich, low-velocity impactors, or endogenic, from freshly exposed mafic material or impact melt, created or exposed by impacts. Here we report Vesta spectra and images and use them to derive and interpret the properties of the 'pure' dark and bright materials. We argue that the dark material is mainly from infall of hydrated carbonaceous material (like that found in a major class of meteorites and some comet surfaces), whereas the bright material is the uncontaminated indigenous Vesta basaltic soil. Dark material from low-albedo impactors is diffused over time through the Vestan regolith by impact mixing, creating broader, diffuse darker regions and finally Vesta's background surface material. This is consistent with howardite-eucrite-diogenite meteorites coming from Vesta.

Spectroscopic characterization of mineralogy and its diversity across Vesta.

The mineralogy of Vesta, based on data obtained by the Dawn spacecraft's visible and infrared spectrometer, is consistent with howardite-eucrite-diogenite meteorites. There are considerable regional and local variations across the asteroid: Spectrally distinct regions include the south-polar Rheasilvia basin, which displays a higher diogenitic component, and equatorial regions, which show a higher eucritic component. The lithologic distribution indicates a deeper diogenitic crust, exposed after excavation by the impact that formed Rheasilvia, and an upper eucritic crust. Evidence for mineralogical stratigraphic layering is observed on crater walls and in ejecta. This is broadly consistent with magma-ocean models, but spectral variability highlights local variations, which suggests that the crust can be a complex assemblage of eucritic basalts and pyroxene cumulates. Overall, Vesta mineralogy indicates a complex magmatic evolution that led to a differentiated crust and mantle.

[The enforcement of the new Italian law on alcohol assumption in work activities with high accident risk in Lombardy]. / Stato di applicazione della normativa sul consumo di alcolici nelle attività ad elevato rischio di infortunio in Lombardia.

The 125/2001, the national law that forbids the alcohol consumption by workers with work tasks having high accident risks, has been activated a year ago. We carried out in Lombardy a research to evaluate the state of enforcement of the law in firms having different work activities. We found a complete application of the law only in very few firms. We think that the Occupational Health doctors should give more attention to the problem of alcohol consumption at the work places, giving the firms their specific scientific and medical support, using the peculiar knowledge of our discipline.

[The assessment of the coronary risk in a work setting. The results of the SEMM study and the outlook for prevention in Italy. Surveillance of Employees Municipality of Milan]. / Valutazione del rischio coronarico in collettività lavorative. Risultati dello studio SEMM (Surveillance of Employees Municipality of Milan) e prospettive di prevenzione in Italia.

BACKGROUND: The goals of the present report are to assess the differences in distribution of traditional coronary risk factors in a work setting, aimed at identifying specific groups at risk and to compare mean values of such risk factors and of an overall risk score of the entire working sample with the results observed in the third WHO-MONICA population survey carried out in northern Italy (Area Brianza). METHODS: In the SEMM study 7872 employees (2601 men and 5271 women) were enrolled between 1992 and 1996. The third MONICA survey in Brianza was carried out on an age- and gender-stratified random sample of 831 men and 884 women in 1993-1994, selected from the 25-64-year-old residents of five municipalities, representative of the study population. In both studies coronary risk factors were measured according to the MONICA protocol, adopting standardized methods. RESULTS: In comparison with the MONICA population sample, the entire working group showed lower mean levels of blood pressure and total cholesterol, higher prevalence of current cigarette smokers and lower mean levels of HDL cholesterol, in both gender groups. Prevalence of overweight subjects was higher among men in the working group, but the opposite pattern was detected in women. The overall risk score, calculated using the coefficients of a proportional hazard survival equation estimated in a large collaborative Italian follow-up study, resulted lower in the working sample, in both gender groups. This result may be attributed to a selection bias known in occupational epidemiology as "healthy worker effect". In contrast to this finding, the prevalence of smokers, in particular among women, was higher in the employed sample, indicating that working stress conditions may play some role. CONCLUSIONS: In order to extend the assessment of cardiovascular risk factors as well as prevention activities in work settings, some advantages are highlighted: the high participation rates, the feasibility to adopt standardized protocols, and easier and cheap procedures for censoring in follow-up studies. Moreover, due to the recently adopted legislation in Italy which increases the number of working categories to be included in periodic clinical examinations, prevention activities in work settings to contrast the epidemic of widespread chronic diseases, like cardiovascular diseases, are encouraged. This will also allow for the investigation of individual variations over time of coronary risk factors.

Dioxin exposure and non-malignant health effects: a mortality study.

OBJECTIVE: To investigate, in a population heavily exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the possible unusual occurrence of diseases other than cancer. METHODS: Five year extension of the follow up of the cohort involved in the Seveso accident. Soil measurements identified three exposure zones: (A) highest contamination, (B) substantial, and (R) low but higher than background contamination. Blood TCDD measurements, although limited in number, confirmed zone exposure ranking. The 15 year mortality in the exposed cohort was compared with that of a large population in the surrounding non-contaminated territory. Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated with Poisson regression techniques. RESULTS: The already noted increased occurrence of cardiovascular deaths was confirmed, in particular in zone A, among males for chronic ischaemic heart disease (five deaths, RR 3.0, 95% CI 1.2 to 7.3), and among females for hypertensive disease (three deaths, RR 3.6, 95% CI 1.2 to 11.4) and chronic rheumatic heart disease. Novel findings were the increase of chronic obstructive pulmonary disease, most notably among males in zone A (four deaths, RR 3.7, 95% CI 1.4 to 9.9) and females in zone B (seven deaths, RR 2.4, 95% CI 1.1 to 5.1); and from diabetes, which was significantly increased in females in zone B (13 deaths, RR 1.9, 95% CI 1.1 to 3.2). In zone R, chronic ischaemic heart disease (males and females), hypertension (females), and diabetes (females) showed less pronounced, although significant excesses. CONCLUSIONS: As well as high TCDD exposure, the accident caused a severe burden of strain in the population. Both these factors might have contributed to the noted increased risks (in particular, circulatory and respiratory). The cardiovascular and immune toxicity of TCDD, as well as its complex interaction with the endocrine system, might be relevant to the explanations of these findings. These results, although not conclusive, concur with previous data in suggesting cardiopulmonary and endocrine effects in humans highly exposed to TCDD.

[Bis-chloromethyl ether and carcinogenesis of alkylating agents]. / Bis-Cloro-Metil-Etere e cancerogenicità da sostanze alchilanti.

Bis-Chloro-Methyl-Ether is an alkylating agent and a recognised carcinogen. It can form spontaneously from the reaction of chloridric acid with formaldehyde. In the past it was extensively used as a chemical intermediate in organic synthesis, particularly as a crosslinking agent in the manufacture of ion-exchange resins. Recently, since its carcinogenicity has been proved in animal studies and confirmed in epidemiological studies of occupationally exposed cohorts, its use has been consistently reduced. A characteristic association has been observed between BCME exposure and a peculiar lung cancer histotype (oat cell carcinoma). In spite of these data, little information is available on the molecular alterations related to BCME exposure and possibly to its carcinogenic activity. Some suggestions can reasonably be obtained considering how the class of alkylating agents acts. They form adducts, binding different positions of DNA bases. The reaction that seems more relevant for mutagenesis and carcinogenesis is the alkylation at the atom O6 of guanine in DNA, which is followed by mis-coding and GC-->AT transition mutation. This kind of alteration determines the activation of a group of enzyme like DNA repair, mismatch repair, excision repair and a specific one, methyl guanine methyl transferase (MGMT). This last repair protein transfers alkyl groups from the O6 position of guanine to an internal cysteine residue, inactivating itself. Thus, the possibility for the cell to eliminate alkylated DNA bases depends strictly upon the cellular content of MGMT. In this view reduced or absent levels of the enzyme are associated with an increased number of adducts and hence increased risk of DNA mutations and cancer. At the moment no molecular studies in vivo have been performed to verify this hypothesis. The peculiar association BCME-oat cell carcinoma, the most chemosensitive tumor, need further investigation.

Measurement of ionized magnesium with AVL 988/4 electrolyte analyzer: preliminary analytical and clinical results.

Only free magnesium has biological activity: technology for measuring the ionized fraction of magnesium is now available via ion-selective electrodes. We have evaluated an instrument (AVL 988/4) which determines ionized magnesium (cMg2+) with an ion-selective electrode based on the ionophore ETH 7025. The selectivity of the electrode is adequate for the ions normally present in plasma, except for calcium: the interference is automatically corrected by simultaneous measurements of calcium with compensation for the calcium interference to the magnesium signal. We have first verified possible interference caused by sampling procedures: known silicon interference has been avoided by use of glass tubes (BD Vacutainer with no additive, code 7626); heparin interference has been measured and found significant above 20 UI.mL-1 of plasma. Instrument evaluation according to NCCLS protocol gives the following imprecision results on 20 replicated analyses: cMg2+ (mmol.L-1) 1.29, 0.76, 0.23, CVs% (within-run) 0.67, 0.67, 3.00 and CVs% (between-run) 4.06, 3.91, 5.89 respectively. Linearity (in the range 0.23-1.60 mmol.L-1) was: measured cMg2+ = 0.981.(calculated cMg2+) + 0.009 mmol/L; r = 0.999. In healthy adults (n = 103) cMg2+ was in the range 0.46-0.74 mmol.L-1 (with a mean of 0.60 mmol/L and normal distribution). These values represent 57% to 84% of serum total magnesium concentration (TMg) (mean 71%). pH dependence of cMg2+ is present, usually to a lower extent with respect to cCa2+, but it seems different in patients with real or in vitro provoked acidosis and in hemodialyzed patients. Citrate interference on ionized magnesium measurements was found both in vitro and in vivo, whilst that due to lactate was demonstrated only in vitro. On a wide range of cMg2+ (n = 100), a good correlation is obtained both with TMg and ultrafiltrable Mg (UFMg): cMg2+ = 0.723.TMg + 0.008 mmol.L-1, r = 0.978; cMg2+ = 0.912.UFMg + 0.10 mmol.L-1, r = 0.968, respectively. The ionized magnesium in ultrafiltrate was found 25% lower than that in serum. The lifespan of the electrode, evaluated on the basis of both time from installation and on number of measured samples, was estimated longer than 4 months and able to analyze more than 1500 samples, whichever comes first. The four electrodes we used during 18 months behaved all the same way. The correlation between measurements performed in whole blood (WB-cMg2+) and in the corresponding serum (S-cMg2+) was excellent: WB-cMg2+ = 0.954.S-cMg2+ +0.02 mmol.L-1; r = 0.998; n = 60.

Angiotensin-converting enzyme inhibition and radial artery compliance in patients with congestive heart failure.

Congestive heart failure is characterized by a clear-cut impairment of arterial compliance of medium-sized arteries, but whether this alteration is irreversible or can be favorably affected by cardiovascular drugs currently used in congestive heart failure treatment is unknown. We studied 9 congestive heart failure patients (New York Heart Association class II; age, [mean +/- SEM] 60.7 +/- 3.3 years) receiving diuretic and digitalis treatment in whom arterial compliance was assessed at the level of the radial artery by an echotracking device capable of measuring the arterial diameter along the entire cardiac cycle. Beat-to-beat arterial blood pressure was concomitantly measured by a Finapres device that allowed diameter-pressure curves and compliance-pressure curves (Langewouters' formula) to be calculated for the entire systolic-diastolic blood pressure range. Arterial compliance was expressed as the area under the compliance-pressure curve normalized for pulse pressure (compliance index). Data were collected before and after 4 and 8 weeks of oral administration of benazepril (10 mg/day). Ten healthy subjects were studied before and after an observational period of 4 weeks (5 subjects) or 8 weeks (5 subjects), and 9 age-matched mildly essential hypertensive subjects studied before and after 4 to 12 weeks of benazepril administration served as control subjects. In congestive heart failure patients, baseline compliance index was significantly less than in normotensive and hypertensive subjects. However, the compliance index showed a marked increase after 4 weeks of benazepril administration (+95.7 +/- 24.9%, P < .05); the increase was also marked after 8 weeks of angiotensin-converting enzyme inhibitor treatment (+77.7 +/- 4.2%, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Structural cardiovascular alterations and blood pressure variability in human hypertension.

AIM: To evaluate the cardiovascular risk of hypertensive patients in relation to left ventricular hypertrophy, arteriolar hypertrophy and blood pressure variability, and the effects of antihypertensive treatment. LEFT VENTRICULAR HYPERTROPHY: In hypertensive subjects with marked left ventricular hypertrophy, cardiovascular problems are about three times more frequent than in hypertensives who do not have left ventricular hypertrophy. The evidence suggests, however, that a moderate degree of left ventricular hypertrophy may be compensatory and that regression of mild hypertrophy should not necessarily be pursued. ARTERIOLAR HYPERTROPHY: An increased wall to lumen ratio leads to an increase in vascular resistance and thus promotes hypertension. Regression of this alteration with antihypertensive treatment appears to be both beneficial and achievable, although it is not clear whether all antihypertensive agents have the same effect. Moreover, there are methodological problems in determining whether a regression has actually been achieved. BLOOD PRESSURE VARIABILITY: There is evidence to suggest that end-organ damage is more frequent and more marked in hypertensives with greater 24 h blood pressure variability. It appears that antihypertensive treatment does not easily reduce this variability, although the intermittent measurements taken by automatic monitoring devices do not fully reflect patterns of blood pressure variation. It may be that hypertensives with a greater degree of blood pressure variability can obtain a reduction in the magnitude of this variability with antihypertensive treatment.

[Changes in the compliance of the radial artery in normotensive subjects with familial hypercholesterolemia]. / Modificazioni della compliance dell'arteria radiale in soggetti normotesi con ipercolesterolemia familiare.

BACKGROUND: Recent studies have shown that in normotensive hypercholesterolemic subjects endothelial dependent dilatation of arterioles is impaired. METHODS: We studied the effects of hypercholesterolemia on arterial compliance in normotensive subjects of both sexes, with a normal serum cholesterol (n = 8, total serum cholesterol = 209 +/- 7 mg/dl, means +/- SEM), an elevated serum cholesterol (n = 8, 285 +/- 8 mg/dl) and familial hypercholesterolemia (n = 8, 393 +/- 20 mg/dl). All subjects were normotensive and devoid of clinical and laboratory evidence of atherosclerotic lesions. The mean age of the 3 groups was 46.7 +/- 2.5, 51.5 +/- 2.9 and 49.8 +/- 2.9 years respectively. In hypercholesterolemic subjects use of hypolipidemic drugs was stopped 2 months before the study. Arterial compliance was measured from the radial artery by an echo-tracking device capable of providing radial artery diameter and, with the addition of a Finapres device, diameter/pressure and compliance/pressure curves continuously over the systolic-diastolic blood pressure range. RESULTS: Mean arterial pressure was similar in the three groups (84.5 +/- 6.1, 79.8 +/- 2.4 and 73.1 +/- 4.4 mm Hg). Arterial compliance was similar in normocholesterolemic and non familial hypercholesterolemic subjects but it was strikingly reduced (50%) in familial hypercholesterolemic subjects. The reduction was even more evident following prolonged local ischemia because while in the first two groups arterial compliance increased after ischemia, in familial hypercholesterolemia no increase occurred. CONCLUSIONS: Thus, familial hypercholesterolemia is accompanied by a striking CONCLUSIONS: Thus, familial hypercholesterolemia is accompanied by a striking reduction in radial artery compliance, i.e. a marked increase in arterial wall stiffness. This may increase the traumatic effect of blood pressure on the arterial wall, favouring atherosclerosis. The lack of compliance alterations in non familial hypercholesterolemia suggests that this hemodynamic disturbance either occurs when serum cholesterol is more markedly increased or it has a genetic origin.

[Respiratory atopy and season of birth: epidemiologic considerations]. / Atopia respiratoria e stagione di nascita: considerazioni epidemiologiche.

Numerous environmental conditions have been considered factors which may favour atopic disease. 320 children (233 males and 87 females, aged from 1 year and 10 months to 16 years and 6 months) were followed at the Out-patients' Department for Allergology of the V Pediatric Clinic (University of Milano). These children were examined in order to determine possible environmental factors, which could be related to subsequent allergic sensitization in infancy. We excluded all the subjects with a high atopic risk owing to: gestational age under 36 weeks, weight at birth under 2,500 Kg, respiratory distress in infancy, bronchiolitis in the first 6 months of life, particularly unfavourable conditions of the domestic microclimate. We did not find any correlation between the length of the period of breast feeding alone and the subsequent appearance of atopic sensitization. The only factor which could be related to atopic sensitization was the season of birth: the majority of atopic subjects were born in the period of maximum exposure to their respective allergens. Our data underline the difficulty in planning any efficacious prophylactic measure against respiratory allergy, limiting our possibilities to the improvement of assistance during pregnancy and to newborns and to the realization of better hygienic and environmental conditions.