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1.
Philos Trans A Math Phys Eng Sci ; 377(2154): 20180406, 2019 Sep 23.
Article in English | MEDLINE | ID: mdl-31378178

ABSTRACT

The instrument JIRAM (Jovian Infrared Auroral Mapper), on board the NASA spacecraft Juno, is both an imager and a spectrometer. Two distinct detectors are used for imaging and spectroscopy. The imager acquires Jupiter images in two bands, one of which (L band, 3.3-3.6 µm) is devoted to monitor the H3+ emission. The spectrometer covers the spectral region from 2 to 5 µm (average spectral resolution 9 nm) with a 256 pixels slit that can observe the same scene of the L band imager with some delay. JIRAM scientific goals are the exploration of the Jovian aurorae and the planet's atmospheric structure, dynamics and composition. Starting early July 2016 Juno is orbiting around Jupiter. Since then, JIRAM has provided an unprecedented amount of measurements, monitoring both Jupiter's atmosphere and aurorae. In particular, the camera has monitored Jupiter's poles with very high spatial resolution, providing new insights in both its aurorae and the polar dynamic. The main findings obtained by the L imager are detailed pictures of Jupiter's aurorae showing an extremely complex morphology of the H3+ distribution in the main oval and in the moon's footprints. The spectrometer has enabled the measure the distribution of both H3+ concentration and temperature. The analysis of the north auroral region limb observations shows that the peak density of H3+ is above 750 km and that often it is anticorrelated to the temperature, confirming the infrared cooling effect of H3+. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.

2.
Astron J ; 156(2)2018 Aug.
Article in English | MEDLINE | ID: mdl-30510303

ABSTRACT

We characterize the origin and evolution of a mesoscale wave pattern in Jupiter's North Equatorial Belt (NEB), detected for the first time at 5 µm using a 2016-17 campaign of "lucky imaging" from the VISIR instrument on the Very Large Telescope and the NIRI instrument on the Gemini observatory, coupled with M-band imaging from Juno's JIRAM instrument during the first seven Juno orbits. The wave is compact, with a 1°.1-1°.4 longitude wavelength (wavelength 1300-1600 km, wavenumber 260-330) that is stable over time, with wave crests aligned largely north-south between 14°N and 17°N (planetographic). The waves were initially identified in small (10° longitude) packets immediately west of cyclones in the NEB at 16°N but extended to span wider longitude ranges over time. The waves exhibit a 7-10 K brightness temperature amplitude on top of an ∼210 K background at 5 µm. The thermal structure of the NEB allows for both inertio-gravity waves and gravity waves. Despite detection at 5 µm, this does not necessarily imply a deep location for the waves, and an upper tropospheric aerosol layer near 400-800 mbar could feature a gravity wave pattern modulating the visible-light reflectivity and attenuating the 5-µm radiance originating from deeper levels. Strong rifting activity appears to obliterate the pattern, which can change on timescales of weeks. The NEB underwent a new expansion and contraction episode in 2016-17 with associated cyclone-anticyclone formation, which could explain why the mesoscale wave pattern was more vivid in 2017 than ever before.

3.
Science ; 361(6404): 774-777, 2018 08 24.
Article in English | MEDLINE | ID: mdl-29976795

ABSTRACT

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.

4.
Nature ; 555(7695): 216-219, 2018 03 07.
Article in English | MEDLINE | ID: mdl-29516997

ABSTRACT

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.

5.
J Stroke Cerebrovasc Dis ; 27(2): 494-498, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29100855

ABSTRACT

OBJECTIVE: To evaluate in the follow-up the sensory-motor recovery and quality of life patients 2 months after completion of the Nintendo Wii console intervention and determine whether learning retention was obtained through the technique. METHODS: Five hemiplegics patients participated in the study, of whom 3 were male with an average age of 54.8 years (SD = 4.6). Everyone practiced Nintendo Wii therapy for 2 months (50 minutes/day, 2 times/week, during 16 sessions). Each session lasting 60 minutes, under a protocol in which only the games played were changed, plus 10 minutes of stretching. In the first session, tennis and hula hoop games were used; in the second session, football (soccer) and boxing were used. For the evaluation, the Fulg-Meyer and Short Form Health Survey 36 (SF-36) scales were utilized. The patients were immediately evaluated upon the conclusion of the intervention and 2 months after the second evaluation (follow-up). RESULTS: Values for the upper limb motor function sub-items and total score in the Fugl-Meyer scale evaluation and functional capacity in the SF-36 questionnaire were sustained, indicating a possible maintenance of the therapeutic effects. CONCLUSION: The results suggest that after Nintendo Wii therapy, patients had motor learning retention, achieving a sustained benefit through the technique.


Subject(s)
Exercise Therapy , Hemiplegia/rehabilitation , Stroke Rehabilitation/methods , Stroke/therapy , Upper Extremity/innervation , Video Games , Virtual Reality Exposure Therapy , Female , Follow-Up Studies , Health Status , Hemiplegia/diagnosis , Hemiplegia/physiopathology , Hemiplegia/psychology , Humans , Learning , Longitudinal Studies , Male , Mental Health , Middle Aged , Motor Activity , Motor Neurons , Quality of Life , Recovery of Function , Sensation , Sensory Receptor Cells , Stroke/diagnosis , Stroke/physiopathology , Stroke/psychology , Time Factors , Treatment Outcome
6.
Geophys Res Lett ; 44(15): 7668-7675, 2017 08 16.
Article in English | MEDLINE | ID: mdl-28989207

ABSTRACT

Juno ultraviolet spectrograph (UVS) observations of Jupiter's aurora obtained during approach are presented. Prior to the bow shock crossing on 24 June 2016, the Juno approach provided a rare opportunity to correlate local solar wind conditions with Jovian auroral emissions. Some of Jupiter's auroral emissions are expected to be controlled or modified by local solar wind conditions. Here we compare synoptic Juno-UVS observations of Jupiter's auroral emissions, acquired during 3-29 June 2016, with in situ solar wind observations, and related Jupiter observations from Earth. Four large auroral brightening events are evident in the synoptic data, in which the total emitted auroral power increases by a factor of 3-4 for a few hours. Only one of these brightening events correlates well with large transient increases in solar wind ram pressure. The brightening events which are not associated with the solar wind generally have a risetime of ~2 h and a decay time of ~5 h.

7.
Nature ; 549(7670): 66-69, 2017 09 06.
Article in English | MEDLINE | ID: mdl-28880294

ABSTRACT

The most intense auroral emissions from Earth's polar regions, called discrete for their sharply defined spatial configurations, are generated by a process involving coherent acceleration of electrons by slowly evolving, powerful electric fields directed along the magnetic field lines that connect Earth's space environment to its polar regions. In contrast, Earth's less intense auroras are generally caused by wave scattering of magnetically trapped populations of hot electrons (in the case of diffuse aurora) or by the turbulent or stochastic downward acceleration of electrons along magnetic field lines by waves during transitory periods (in the case of broadband or Alfvénic aurora). Jupiter's relatively steady main aurora has a power density that is so much larger than Earth's that it has been taken for granted that it must be generated primarily by the discrete auroral process. However, preliminary in situ measurements of Jupiter's auroral regions yielded no evidence of such a process. Here we report observations of distinct, high-energy, downward, discrete electron acceleration in Jupiter's auroral polar regions. We also infer upward magnetic-field-aligned electric potentials of up to 400 kiloelectronvolts, an order of magnitude larger than the largest potentials observed at Earth. Despite the magnitude of these upward electric potentials and the expectations from observations at Earth, the downward energy flux from discrete acceleration is less at Jupiter than that caused by broadband or stochastic processes, with broadband and stochastic characteristics that are substantially different from those at Earth.

8.
Science ; 356(6340): 821-825, 2017 05 26.
Article in English | MEDLINE | ID: mdl-28546206

ABSTRACT

On 27 August 2016, the Juno spacecraft acquired science observations of Jupiter, passing less than 5000 kilometers above the equatorial cloud tops. Images of Jupiter's poles show a chaotic scene, unlike Saturn's poles. Microwave sounding reveals weather features at pressures deeper than 100 bars, dominated by an ammonia-rich, narrow low-latitude plume resembling a deeper, wider version of Earth's Hadley cell. Near-infrared mapping reveals the relative humidity within prominent downwelling regions. Juno's measured gravity field differs substantially from the last available estimate and is one order of magnitude more precise. This has implications for the distribution of heavy elements in the interior, including the existence and mass of Jupiter's core. The observed magnetic field exhibits smaller spatial variations than expected, indicative of a rich harmonic content.

9.
Science ; 356(6340): 826-832, 2017 05 26.
Article in English | MEDLINE | ID: mdl-28546207

ABSTRACT

The Juno spacecraft acquired direct observations of the jovian magnetosphere and auroral emissions from a vantage point above the poles. Juno's capture orbit spanned the jovian magnetosphere from bow shock to the planet, providing magnetic field, charged particle, and wave phenomena context for Juno's passage over the poles and traverse of Jupiter's hazardous inner radiation belts. Juno's energetic particle and plasma detectors measured electrons precipitating in the polar regions, exciting intense aurorae, observed simultaneously by the ultraviolet and infrared imaging spectrographs. Juno transited beneath the most intense parts of the radiation belts, passed about 4000 kilometers above the cloud tops at closest approach, well inside the jovian rings, and recorded the electrical signatures of high-velocity impacts with small particles as it traversed the equator.

10.
Panminerva Med ; 56(3): 195-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25056243

ABSTRACT

Helicobacter pylori (H. pylori) is involved in the development of several gastroduodenal diseases. Since the latest decade, several studies have reported on the link between chronic H. pylori infection and a variety of extragastric manifestations, including dementia. To identify the publications on the association between H. pylori and dementia, a MEDLINE search was conducted. Although case-control studies reported controversial data, a recent longitudinal population-based cohort study found that after 20 years of follow-up, 28.9% of H. pylori-positive versus 21.1% of H. pylori-negative subjects developed dementia. After correction for confounding factors, the infection was significantly associated with higher risk of developing dementia (P=0.04). Moreover, in another study evaluating the effect of H. pylori eradication on the progression of dementia in Alzheimer's disease patients with peptic ulcer, the cure of the bacterium was associated with a decreased risk of dementia progression compared to persistent infection. To date, defining H. pylori as a target for prevention or treatment of dementia remains a topic with much controversy but of essence, as any relationship would reduce, due to the cost-effectiveness of the therapy, a burden on the National Health Care budget. The need for extensive studies with appropriate epidemiological and clinical approaches is crucial to investigate a potential causal relationship.


Subject(s)
Dementia/complications , Dementia/microbiology , Helicobacter Infections/complications , Helicobacter Infections/physiopathology , Age Factors , Aged , Alzheimer Disease/complications , Alzheimer Disease/microbiology , Case-Control Studies , Cost-Benefit Analysis , Disease Progression , Female , Helicobacter pylori , Humans , Longitudinal Studies , Male
11.
Panminerva Med ; 56(2): 145-9, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24994578

ABSTRACT

AIM: The decrease in bone density may occur as a result of inflammatory bowel disease (IBD). Studies conducted on this issue generally focused on treated IBD patients. It is thus difficult to discriminate the role of disease from the effect of therapy on bone density reduction. We evaluated the prevalence of osteopenia/osteoporosis and abnormalities in indices of bone metabolism in patients with newly diagnosed IBD. METHODS: Evaluation of dual-energy X-ray absorptiometry (DXA) at the lumbar spine and intact parathormone (PTH), 25-hydroxy vitamin D and urinary cross-links, on 37 (26 females, median age 35.6±14.5 years) consecutive patients. RESULTS: Sixteen of 37 patients (43%) had normal DXA, 17 (46%) were osteopenic and 4 (11%) osteoporotics. Most male patients >30 years (63%) old as well as young women (62%) had osteopenia/osteoporosis. Mean value of intact-PTH was significantly higher in women >50 years (55.0±18.1 pg/mL) compared with those aged 16-20 years (30.0±14.6 pg/mL) (P=0.042). Furthermore, there was a significant difference between mean value of 25-hydroxy vitamin D in women >50 years old (16.2±4.7 ng/mL) compared to those aged 21-30 years (26.6±7.9 ng/mL) (P=0.041). Intact-PTH was significantly higher in osteoporotic patients (55.7±12.7 pg/mL) compared to normal subjects (28.3±13.0 pg/mL) (P=0.0014). CONCLUSION: High prevalence of osteopenia/osteoporosis was observed in this population. On the basis of these data, we propose to perform DXA in male patients aged >30 years and in all women with new diagnosis of IBD.


Subject(s)
Bone Diseases, Metabolic/epidemiology , Inflammatory Bowel Diseases/complications , Osteoporosis/epidemiology , Absorptiometry, Photon/methods , Adult , Aged , Bone Density , Bone Diseases, Metabolic/blood , Bone Diseases, Metabolic/complications , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Osteoporosis/blood , Osteoporosis/complications , Parathyroid Hormone/blood , Postmenopause , Prevalence , Prospective Studies , Vitamin D/analogs & derivatives , Vitamin D/blood
12.
Minerva Med ; 105(1): 1-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24572448

ABSTRACT

Helicobacter pylori (H. pylori) has been conclusively related to several gastroduodenal diseases. The possible role of the bacterium in the development of extragastric manifestations has been investigated in the past few years. To identify all publications on the association between H. pylori and respiratory diseases, a MEDLINE search of all studies published in English from 1965 to 2013 was conducted. All data are based on case-control studies. Controversial findings of H. pylori seroprevalence have been obtained in patients with bronchial asthma, lung cancer, pulmonary tuberculosis, sarcoidosis, cystic fibrosis, chronic bronchitis and bronchiectasis. At present, on epidemiological bases, there is no definite evidence of a causal relationship between H. pylori infection and respiratory diseases. There is a low consideration of confounding factors as poorer socioeconomic status and tobacco use. The activation of pro-inflammatory cytokines by H. pylori might be a possible pathogenetic mechanism. However, there are no convincing data about the influence of H. pylori on the inflammatory changes of the bronchoepithelium so far. Further studies are needed on the impact of H. pylori eradication, on the prevention, development and natural history of these disorders.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Respiratory Tract Diseases/microbiology , Asthma/microbiology , Bronchiectasis/microbiology , Bronchitis, Chronic/microbiology , Cystic Fibrosis/microbiology , Humans , Lung Diseases/microbiology , Lung Neoplasms/microbiology , Sarcoidosis, Pulmonary/microbiology , Tuberculosis, Pulmonary/microbiology
14.
Neurosci Lett ; 471(1): 6-9, 2010 Feb 26.
Article in English | MEDLINE | ID: mdl-20056132

ABSTRACT

There is an emerging body of data suggesting that bipolar disorder is associated with DNA damage. Intracerebroventricular (i.c.v.) administration of ouabain in rats results in manic-like alterations. We evaluated DNA damage of peripheral blood, cerebrospinal fluid and hippocampus of rats after i.c.v. ouabain injection. Ouabain-induced hyperlocomotion was examined in an open field. Additionally, we used single cell gel electrophoresis (comet assay) to measure early transient damage in cerebrospinal fluid (CSF), hippocampus and blood; and the micronucleus test to measure persistent damage in total blood samples of rats after ouabain administration. Our findings demonstrated that ouabain induced hyperlocomotion in rats, and this response remained up to 7 days following a single i.c.v. injection. In addition, we observed that the persistent increase in the rat spontaneous locomotion is associated with increased hippocampal and peripheral index of early DNA damage in rats. No significant alterations were observed in the micronucleus frequency in total blood samples of the rats after the ouabain i.c.v. injection. These results suggest that ouabain may induce peripheral and central early DNA damage, but this early damage may be repaired.


Subject(s)
Bipolar Disorder/genetics , DNA Damage , Ouabain , Animals , Bipolar Disorder/chemically induced , Bipolar Disorder/psychology , Comet Assay , DNA/blood , DNA/cerebrospinal fluid , DNA/metabolism , Disease Models, Animal , Hippocampus/metabolism , Injections, Intraventricular , Male , Micronucleus Tests , Motor Activity , Rats , Rats, Wistar
15.
Nature ; 450(7170): 641-5, 2007 Nov 29.
Article in English | MEDLINE | ID: mdl-18046396

ABSTRACT

The upper atmosphere of a planet is a transition region in which energy is transferred between the deeper atmosphere and outer space. Molecular emissions from the upper atmosphere (90-120 km altitude) of Venus can be used to investigate the energetics and to trace the circulation of this hitherto little-studied region. Previous spacecraft and ground-based observations of infrared emission from CO2, O2 and NO have established that photochemical and dynamic activity controls the structure of the upper atmosphere of Venus. These data, however, have left unresolved the precise altitude of the emission owing to a lack of data and of an adequate observing geometry. Here we report measurements of day-side CO2 non-local thermodynamic equilibrium emission at 4.3 microm, extending from 90 to 120 km altitude, and of night-side O2 emission extending from 95 to 100 km. The CO2 emission peak occurs at approximately 115 km and varies with solar zenith angle over a range of approximately 10 km. This confirms previous modelling, and permits the beginning of a systematic study of the variability of the emission. The O2 peak emission happens at 96 km +/- 1 km, which is consistent with three-body recombination of oxygen atoms transported from the day side by a global thermospheric sub-solar to anti-solar circulation, as previously predicted.

16.
Nature ; 450(7170): 637-40, 2007 Nov 29.
Article in English | MEDLINE | ID: mdl-18046395

ABSTRACT

Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole. The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition.

17.
Science ; 290(5497): 1756-8, 2000 Dec 01.
Article in English | MEDLINE | ID: mdl-11099412

ABSTRACT

A comprehensive investigation of polar stratospheric clouds was performed on 25 January 2000 with instruments onboard a balloon gondola flown from Kiruna, Sweden. Cloud layers were repeatedly encountered at altitudes between 20 and 24 kilometers over a wide range of atmospheric temperatures (185 to 197 kelvin). Particle composition analysis showed that a large fraction of the cloud layers was composed of nitric acid trihydrate (NAT) particles, containing water and nitric acid at a molar ratio of 3:1; this confirmed that these long-sought solid crystals exist well above ice formation temperatures. The presence of NAT particles enhances the potential for chlorine activation with subsequent ozone destruction in polar regions, particularly in early and late winter.

18.
Appl Opt ; 38(21): 4425-32, 1999 Jul 20.
Article in English | MEDLINE | ID: mdl-18323927

ABSTRACT

Different definitions for estimating the degree of changes in signal polarization measured by lidar measurements are used both to detect the presence of nonspherical aerosol particles and to estimate their shape and density. Our aim is to provide a tool for calculation and interpretation of changes in polarization that are due to aerosol backscatter measured by the lidar technique. An overview of several techniques used to calculate linear depolarization from two-channel lidar measurements is given. Advantages and disadvantages of each method are analyzed when we apply them on a lidar vertical profile. Systematic errors are also discussed. First, an overview of different estimations of polarizability of atmospheric molecules is given. The presence of signal with orthogonal polarization in each channel (cross talk) is a source of error in depolarization estimation. It is calculated at various degrees of contamination, and the total uncertainty on depolarization definition is retrieved.

19.
Appl Opt ; 35(27): 5345-7, 1996 Sep 20.
Article in English | MEDLINE | ID: mdl-21127529

ABSTRACT

A novel approach to single-photon detection by means of an avalanche photodiode is described and preliminary results obtained by implementation of a prototype are reported. The electronic circuit (breakdown voltage follower) avoids the use of complex temperature controls typically used with these devices, thus reducing system complexity and cost. Data obtained without any thermoregulation show the same behavior with respect to systems thermoregulated to within a few hundredths of a degree celsius.

20.
Minerva Cardioangiol ; 41(10): 457-63, 1993 Oct.
Article in Italian | MEDLINE | ID: mdl-8302442

ABSTRACT

The anti-hypertensive activity and influence on some forms of stress of slow-release Nicardipoine and Captopril were compared using a randomized 2:1 protocol. Thirty-six patients, mean age 55.9 years, suffering from slight or moderate arterial hypertension were treated with either 40 mg of Nicardipine retard twice a day (b.i.d.), or Captopril in a dose of 25 mg (b.i.d.) for 8 weeks. A significant reduction was observed in arterial pressure, both in orthostatism and clinostatism, following both treatments in comparison to the placebo period, but the group treated with slow-release Nicardipine showed a greater and statistically significant reduction in arterial pressure. No significant change in heart rate was reported using either drug. Non-invasive out-patient monitoring of arterial pressure, performed using Spacelabs 5300, showed a significant reduction in arterial pressure using both drugs and the conservation of the normal circadian rhythm of arterial pressure. The pressure response to the cold pressor test (CPT), mental arithmetic test (MAS), and to dynamic and isometric effort was positive with both drugs, thus revealing a degree of protection offered by treatment using these two substances. In overall terms, the two drugs were well tolerated.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Hypertension/drug therapy , Nicardipine/therapeutic use , Adult , Aged , Delayed-Action Preparations , Drug Evaluation , Female , Humans , Male , Middle Aged
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