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1.
Article in English | MEDLINE | ID: mdl-38666685

ABSTRACT

Persons with HIV (PWH) face an increased risk of cardiovascular events due to immune activation, comorbidities, and certain antiretrovirals (ARVs). However, the current cardiovascular risk (CVR) scores are not specifically directed toward PWH. This study aimed to assess the agreement between different predictive CVR scores and explore their relationship with clinical and demographic data in Mexican PWH. A descriptive cross-sectional analysis was conducted in 200 PWH with a mean age of 42 years who were treated at a Mexican urban center from 2017 to 2018. The majority (83%) was on ARV treatment and 79.5% had undetectable viral loads (VLs). Moderate- to high-risk scores were infrequent, with Framingham Risk Score for Hard Coronary Heart Disease scores showing higher values, with very low concordance among all scores. Logistic regression analysis revealed significant associations between the CVR scores and the initial recorded VL, CD4 cell count, and elevated triglyceride levels. However, no associations were found with measures such as body mass index or abdominal circumference. Treatment with integrase strand transfer inhibitors (INSTIs), particularly first-generation inhibitors, showed strong associations with all predictive scores, notably ASCVD (odds ratio = 7.03, 95% confidence interval 1.67-29.64). The poor concordance among the CVR scores in PWH highlights the need for a specific score that considers comorbidities and ARV drugs. Despite the relatively young age of the participants, significant correlations were observed between INSTI use, initial VL, CD4 cell count, and triglyceride levels, which are factors not considered in the existing risk scores. Regardless of the actual value of the scores, screening for CVR in PWH is recommended.

2.
Eur J Obstet Gynecol Reprod Biol ; 297: 132-137, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38626514

ABSTRACT

OBJECTIVES: Numerous animal and epidemiologic studies have demonstrated a positive association between maternal obesity in pregnancy and obesity in offspring. The biologic mechanisms of this association remain under investigation. One proposed mechanism includes fetoplacental endothelial dysfunction secondary to inflammation. Endocan is a relatively new biomarker for endothelial dysfunction and inflammation. Our objectives were to examine (1) the association between maternal obesity and neonatal serum endocan at birth, and (2) the association between neonatal serum endocan at birth and pediatric obesity at 24-36 months of age. STUDY DESIGN: This was a secondary analysis of a prospective cohort of neonates born < 33 weeks gestation. Serum endocan was collected within 48 hours of birth. Serum endocan levels were compared in neonates born to obese mothers vs. those born to non-obese mothers. BMI data were retrospectively collected from cohort neonates between 24 and 36 months of age. RESULTS: The analysis included 120 mother/neonate dyads. Neonates born to obese mothers had higher median serum endocan at birth compared to neonates born to non-obese mothers (299 ng/L [205-586] vs. 251 ng/L [164-339], p = 0.045). In a linear regression modeled on neonatal serum endocan level, maternal obesity had a statistically significant positive association (p = 0.021). Higher mean serum endocan level at birth was associated with pediatric obesity between 24 and 36 months (obese vs. non-obese offspring; 574 ng/L (222) vs. 321 ng/L (166), p = 0.005). CONCLUSIONS: In our cohort of preterm neonates, elevated serum endocan at birth was associated with both maternal obesity and downstream pediatric obesity. More research is needed to understand intergenerational transmission of obesity. A large focus has been on epigenetic modification. Endothelial dysfunction and inflammation may play important roles in these pathways. Effective biomarkers, including endocan, may also serve as intermediate outcomes in future pregnancy research.

3.
Vestn Otorinolaringol ; 88(2): 10-16, 2023.
Article in Russian | MEDLINE | ID: mdl-37184548

ABSTRACT

The peculiarities of cochlear implant (CI) processor fitting in children with auditory neuropathy spectrum disorders (ANSD) were investigated. At the 1-st fitting of the CI processor a standard protocol of parameters was used in all patients, including patients with cochlear nerve hypoplasia. After the initial fitting session, the behavioral tonal thresholds with CI in 55% of patients were 30-35 dB, in 32.% of patients - 40-50 dB. After 3-6 months, 65% of children with ANSD showed significant progress in auditory-speech development, which made it possible to use the standard protocol of tuning parameters for them with the most comfortable and threshold levels of electrical stimulation adjusted according to the child's reactions. The best dynamics was observed in 2 children with presynaptic ANSD with a confirmed DFNB9 (OTOF) gene mutation. In 35% of children, there was no progress in distinguishing speech signals and instability of reactions to sounds persisted after 6 months using of CI and speech therapy training, despite the low tonal thresholds of hearing. In these children the coding strategy was changed, the stimulation frequency was reduced, and the pulse width was increased. This helped to improve the discrimination of sounds with CI and progress in the child's speech development. The results demonstrate that children with ANSD require more frequent correction of CI processor settings: 1st year - every 3 months, then at least 2 times a year until the optimal coding strategy and settings are achieved. To predict the effectiveness of CI and determine the optimal tactics for setting up the CI processor in patients with ANSD, the preoperative examination should include MRI of the cerebellopontine angle to detect anomalies of the cochlear nerve and genetic examination to identify mutations that cause hearing impairment in patients with ANSD.


Subject(s)
Cochlear Implantation , Cochlear Implants , Hearing Loss, Central , Hearing Loss, Sensorineural , Child , Humans , Hearing Loss, Central/diagnosis , Hearing Loss, Sensorineural/diagnosis , Hearing Loss, Sensorineural/surgery
4.
J Hosp Infect ; 136: 1-7, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36907332

ABSTRACT

BACKGROUND: Contact precautions are widely used to prevent the transmission of carbapenem-resistant organisms (CROs) in hospital wards. However, evidence for their effectiveness in natural hospital environments is limited. OBJECTIVE: To determine which contact precautions, healthcare worker (HCW)-patient interactions, and patient and ward characteristics are associated with greater risk of CRO infection or colonization. DESIGN, SETTING AND PARTICIPANTS: CRO clinical and surveillance cultures from two high-acuity wards were assessed through probabilistic modelling to characterize a susceptible patient's risk of CRO infection or colonization during a ward stay. User- and time-stamped electronic health records were used to build HCW-mediated contact networks between patients. Probabilistic models were adjusted for patient (e.g. antibiotic administration) and ward (e.g. hand hygiene compliance, environmental cleaning) characteristics. The effects of risk factors were assessed by adjusted odds ratio (aOR) and 95% Bayesian credible intervals (CrI). EXPOSURES: The degree of interaction with CRO-positive patients, stratified by whether CRO-positive patients were on contact precautions. MAIN OUTCOMES AND MEASURES: The prevalence of CROs and number of new carriers (i.e. incident CRO aquisition). RESULTS: Among 2193 ward visits, 126 (5.8%) patients became colonized or infected with CROs. Susceptible patients had 4.8 daily interactions with CRO-positive individuals on contact precautions (vs 1.9 interactions with those not on contact precautions). The use of contact precautions for CRO-positive patients was associated with a reduced rate (7.4 vs 93.5 per 1000 patient-days at risk) and odds (aOR 0.03, 95% CrI 0.01-0.17) of CRO acquisition among susceptible patients, resulting in an estimated absolute risk reduction of 9.0% (95% CrI 7.6-9.2%). Also, carbapenem administration to susceptible patients was associated with increased odds of CRO acquisition (aOR 2.38, 95% CrI 1.70-3.29). CONCLUSIONS AND RELEVANCE: In this population-based cohort study, the use of contact precautions for patients colonized or infected with CROs was associated with lower risk of CRO acquisition among susceptible patients, even after adjusting for antibiotic exposure. Further studies that include organism genotyping are needed to confirm these findings.


Subject(s)
Cross Infection , Humans , Cross Infection/epidemiology , Cross Infection/prevention & control , Carbapenems/pharmacology , Cohort Studies , Bayes Theorem , Infection Control/methods , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Intensive Care Units
5.
Geophys Res Lett ; 49(23): e2022GL099285, 2022 Dec 16.
Article in English | MEDLINE | ID: mdl-37034391

ABSTRACT

The Juno spacecraft has been in orbit around Jupiter since 2016. Two flybys of Ganymede were executed in 2021, opportunities realized by evolution of Juno's polar orbit over the intervening 5 years. The geometry of the close flyby just prior to the 34th perijove pass by Jupiter brought the spacecraft inside Ganymede's unique magnetosphere. Juno's payload, designed to study Jupiter's magnetosphere, had ample dynamic range to study Ganymede's magnetosphere. The Juno radio system was used both for gravity measurements and for study of Ganymede's ionosphere. Remote sensing of Ganymede returned new results on geology, surface composition, and thermal properties of the surface and subsurface.

6.
Science ; 374(6570): 968-972, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34709937

ABSTRACT

Jupiter's atmosphere has a system of zones and belts punctuated by small and large vortices, the largest being the Great Red Spot. How these features change with depth is unknown, with theories of their structure ranging from shallow meteorological features to surface expressions of deep-seated convection. We present observations of atmospheric vortices using the Juno spacecraft's Microwave Radiometer. We found vortex roots that extend deeper than the altitude at which water is expected to condense, and we identified density inversion layers. Our results constrain the three-dimensional structure of Jupiter's vortices and their extension below the clouds.

7.
Vestn Otorinolaringol ; 86(1): 30-35, 2021.
Article in Russian | MEDLINE | ID: mdl-33720648

ABSTRACT

THE AIM OF THE STUDY: Was to study the possibility of using a battery of psychoacoustic tests to assess the tuning of the cochlear implant processor (CI) in deaf patients. METHODOLOGY: The study involved 60 prellingually deaf patients aged 10 to 23 years with oral speech skills. To assess the quality of the CI processor tuning, in addition to traditional methods, a special battery of psychoacoustic tests was used. The first block of tests assessed the perception of the basic characteristics of sound signals (duration, temporal structure, spectrum, timbre) and was used to assess the initial setting. The second block of tests, intended for patients with experience using CI, included tasks to distinguish acoustically similar and dynamically changing signals, etc. RESULTS: At the end of the initial CI setup session, patients with short signal perception problems were identified. Adjusting the frequency of electrical stimulation in patients has increased their ability to distinguish between sounds. During the second tuning session of the CI processor, 6 months later, a group of patients with difficulties in perceiving acoustic information in the low-frequency range was identified - distinguishing melodic intervals, changing the pitch of sounds, highlighting the voice of the target speaker. The «problem¼ patients underwent additional correction of the CI processor setting and the corresponding auditory training, which improved the test performance and subjective perception of sounds. CONCLUSION: The use of psychoacoustic tests expands the possibilities of fine tuning the CI processor, taking into account the individual characteristics of the patient's auditory perception at different stages of CI use, especially in «problem¼ patients.


Subject(s)
Cochlear Implantation , Cochlear Implants , Deafness , Speech Perception , Adolescent , Adult , Child , Deafness/diagnosis , Humans , Psychoacoustics , Young Adult
8.
J Hosp Infect ; 107: 35-39, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33038435

ABSTRACT

Opportunity exists to decrease healthcare-related exposure to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), preserve infection control resources, and increase care capacity by reducing the time to diagnosis of coronavirus disease 2019 (COVID-19). A retrospective cohort analysis was undertaken to measure the effect of targeted rapid molecular testing for SARS-CoV-2 on these outcomes. In comparison with standard platform testing, rapid testing was associated with a 65.6% reduction (12.6 h) in the median time to removal from the isolation cohort for patients with negative diagnostic results. This translated to an increase in COVID-19 treatment capacity of 3028 bed-hours and 7500 fewer patient interactions that required the use of personal protective equipment per week.


Subject(s)
COVID-19 Nucleic Acid Testing/statistics & numerical data , COVID-19/diagnosis , COVID-19/prevention & control , Emergency Service, Hospital/statistics & numerical data , Infection Control/methods , Adolescent , Adult , Aged , Female , Humans , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Male , Middle Aged , Retrospective Studies , SARS-CoV-2/genetics , Time Factors , Young Adult
9.
Geophys Res Lett ; 46(16): 9397-9404, 2019 Aug 28.
Article in English | MEDLINE | ID: mdl-31762519

ABSTRACT

The polar orbit of Juno at Jupiter provides a unique opportunity to observe high-latitude energetic particle injections. We measure energy-dispersed impulsive injections of protons and electrons. Ion injection signatures are just as prevalent as electron signatures, contrary to previous equatorial observations. Included are previously unreported observations of high-energy banded structures believed to be remnants of much earlier injections, where the particles have had time to disperse around Jupiter. A model fit of the injections used to estimate timing fits the shape of the proton signatures better than it does the electron shapes, suggesting that electrons and protons are different in their abilities to escape the injection region. We present ultaviolet observations of Jupiter's aurora and discuss the relationship between auroral injection features and in situ injection events. We find, unexpectedly, that the presence of in situ particle injections does not necessarily result in auroral injection signatures.

10.
Bull Exp Biol Med ; 167(1): 53-56, 2019 May.
Article in English | MEDLINE | ID: mdl-31183657

ABSTRACT

The effect of the anti-inflammatory cytokine IL-10 on the ultrastructural distribution of AMPA receptor GluR1 subunit in CA1 field of cultured hippocampal slices was studied by using immunohistochemical technique. It was found that long-term posttetanic potentiation increased the content of GluR1 in the postsynaptic density of the axo-spinous synapse. Addition of IL-10 in concentrations of 1 and 10 ng/ml to the medium facilitated long-term posttetanic potentiation thereby changing the distribution of GluR1 in the spine: the number of receptors increased in the cytoplasm and decreased in the postsynaptic density. It is assumed that activation of neuronal IL-10 receptors affects the distribution of AMPA receptors in axo-spinous synapses of hippocampal field CA1 through interplay of intracellular signaling pathways, thereby participating in the mechanisms of synaptic plasticity under normal conditions.


Subject(s)
Hippocampus/drug effects , Hippocampus/metabolism , Interleukin-10/pharmacology , Receptors, AMPA/metabolism , Animals , Immunohistochemistry , In Vitro Techniques , Long-Term Potentiation/drug effects , Male , Rats , Rats, Wistar
11.
Vestn Otorinolaringol ; 84(2): 29-35, 2019.
Article in Russian | MEDLINE | ID: mdl-31198212

ABSTRACT

The efficacy of sequential bilateral cochlear implantation with long interval between surgeries (18 years) was investigated in deaf-blind patient (22 years old man, lost hearing and vision after meningitis at the age 2.5 years). At the age 4 years he got cochlear implant at right ear. His speech skills completely disappeared before the implantation. Auditory-speech rehabilitation with cochlear implant was successful - patient has good auditory, language, speech, cognitive skills. At the age 22 years patient made decision to get cochlear implant at the left ear after breakdown of internal part of cochlear implant at right ear in spite of successful reoperation. After activation of new processor (all electrodes were activated) the patient got daily auditory training with cochlear implant at left ear (Concerto/Opus 2, Medel) on the base of 'auditory' method, in daily life patient uses 2 devices. After 1 month of using cochlear implant at left ear the patient recognized environmental sounds and music instruments, words and sentences in close set tests EARS battery, the score for OLSA test in quiet was 90%, but the perception in noise was complicated. The balance of parameters of fitting for 1-st and 2-nd processors and special auditory training with two cochlear implants provided the development of initial binaural interaction. Perilinqually deaf patients can achieve high effect after sequential bilateral cochlear implantation with long interval between surgeries. The necessary conditions are - preservation of electrical activity of auditory nerve, intensive structured auditory training with new 'ear', patient's motivation of using of cochlear implant at 'new' ear.


Subject(s)
Blindness , Cochlear Implantation , Cochlear Implants , Deafness , Hearing Loss , Speech Perception , Adult , Blindness/complications , Deafness/complications , Humans , Male , Treatment Outcome , Young Adult
12.
Neurosci Lett ; 704: 95-99, 2019 06 21.
Article in English | MEDLINE | ID: mdl-30953737

ABSTRACT

Using the methods of electrophysiology and immunohistochemistry, the effect of the transforming factor beta-1(TGF-ß1), an anti-inflammatory cytokine, on the long-term post-tetanic potentiation (LTP) in CA1 field hippocampal slices and the distribution of the GluR1 subunit of the AMPA receptor has been studied. It was shown that TGF-ß1 at a concentration of 10 ng/ml did not significantly affect the initial stage of LTP and substantially changed the distribution of synaptic AMPA receptors in response to tetanic stimulation. Twenty five minutes after the tetanization, the main pool of AMPA receptors (90%) was due to the postsynaptic density (PSD). By contrast, LTP in the presence of TGF-ß1 was accompanied by less pronounced changes in the distribution of AMPA receptors. Their localization in both pre- and postsynaptic regions remained nearly the same as that in the control. It may be suggested that the normal distribution of AMPA receptors in spinous synapses promotes the stabilization of potentiated synapses, thereby retaining LTP for longer terms.


Subject(s)
CA1 Region, Hippocampal/physiology , Long-Term Potentiation , Receptors, AMPA/metabolism , Transforming Growth Factor beta1/physiology , Animals , In Vitro Techniques , Male , Rats, Wistar , Transforming Growth Factor beta1/pharmacology
13.
Geophys Res Lett ; 46(1): 19-27, 2019 Jan 16.
Article in English | MEDLINE | ID: mdl-30828110

ABSTRACT

We compare electron and UV observations mapping to the same location in Jupiter's northern polar region, poleward of the main aurora, during Juno perijove 5. Simultaneous peaks in UV brightness and electron energy flux are identified when observations map to the same location at the same time. The downward energy flux during these simultaneous observations was not sufficient to generate the observed UV brightness; the upward energy flux was. We propose that the primary acceleration region is below Juno's altitude, from which the more intense upward electrons originate. For the complete interval, the UV brightness peaked at ~240 kilorayleigh (kR); the downward and upward energy fluxes peaked at 60 and 700 mW/m2, respectively. Increased downward energy fluxes are associated with increased contributions from tens of keV electrons. These observations provide evidence that bidirectional electron beams with broad energy distributions can produce tens to hundreds of kilorayleigh polar UV emissions.

14.
J Neonatal Perinatal Med ; 12(1): 81-86, 2019.
Article in English | MEDLINE | ID: mdl-30347622

ABSTRACT

BACKGROUND: Numerous studies have examined the association between ABO blood groups and adult disease states, but very few have studied the neonatal population. The objective of this study was to determine the relationship between AB blood group and the occurrence of common neonatal disorders such as neutropenia at birth, sepsis, respiratory distress syndrome (RDS), intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), and patent ductus arteriosus (PDA) compared to all other blood groups. METHODS: We performed a retrospective review on 3,981 infants born at 22 0/7 to 42 6/7 weeks' gestational age and compared the relative risk of neonatal diseases in infants with AB blood group to that of infants with all other blood groups (A, B, and O). RESULTS: When compared to all other blood groups, AB infants demonstrated an increased risk for developing negative clinical outcomes. AB blood group was significantly associated with a 14-89% increased risk of neutropenia at birth, sepsis, RDS, and ROP. Risks for IVH and PDA were not significant. CONCLUSION: We hypothesize that the phenotypic expression of A and B antigens, rather than the antigens themselves, in the AB group may reveal an enhanced susceptibility to injury at the endothelial level resulting in an increased risk for disease development.


Subject(s)
ABO Blood-Group System/genetics , Neutropenia/blood , Respiratory Distress Syndrome, Newborn/blood , Retinopathy of Prematurity/blood , Sepsis/blood , ABO Blood-Group System/blood , Female , Genetic Predisposition to Disease , Gestational Age , Humans , Infant, Newborn , Infant, Premature , Intensive Care Units, Neonatal , Male , Neutropenia/genetics , Phenotype , Respiratory Distress Syndrome, Newborn/genetics , Retinopathy of Prematurity/genetics , Retrospective Studies , Risk Factors , Sepsis/genetics
15.
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.

16.
S Afr Med J ; 108(3): 235-239, 2018 Feb 27.
Article in English | MEDLINE | ID: mdl-30004369

ABSTRACT

BACKGROUND: Cervical cancer remains the second most common cancer among women worldwide, with much of the global burden occurring in low- and middle-income countries. HIV-infected women are at increased risk of human papillomavirus infection, preinvasive cervical disease and invasive cervical cancer (ICC). Funded through the United States President's Emergency Plan for AIDS Relief (PEPFAR) and working in collaboration with the South African (SA) Department of Health, our team supports cervical screening integrated within public sector HIV clinics in SA. OBJECTIVES: To estimate the burden of cervical disease among HIV-infected women accessing screening services supported through our programme. METHODS: We constructed conditional probability models to estimate the burden of grade 1 and grades 2/3 cervical intraepithelial lesions (CIN1 and CIN2/3) and ICC among two cohorts: one consisting of 3 190 HIV-infected women for whom only cytology results were available for analysis, and another consisting of 75 358 HIV-infected women for whom neither cytology nor histology results were available. Parameter estimates for the models were derived from routinely collected programmatic data and published clinical trials. RESULTS: Between January 2009 and November 2015, 75 358 HIV-infected women underwent Pap smear screening in public sector clinics supported by our cervical cancer prevention programme. Based on modelling analysis, we estimate that 46 123 cases of CIN1 (range 45 500 - 49 608), 13 598 cases of CIN2/3 (range 12 749 - 14 828), and 104 cases of ICC (range 61 - 186) occurred in this population. CONCLUSIONS: Our findings highlight the magnitude of cervical disease among HIV-infected women in SA.

17.
Nature ; 555(7695): 223-226, 2018 03 07.
Article in English | MEDLINE | ID: mdl-29516995

ABSTRACT

The depth to which Jupiter's observed east-west jet streams extend has been a long-standing question. Resolving this puzzle has been a primary goal for the Juno spacecraft, which has been in orbit around the gas giant since July 2016. Juno's gravitational measurements have revealed that Jupiter's gravitational field is north-south asymmetric, which is a signature of the planet's atmospheric and interior flows. Here we report that the measured odd gravitational harmonics J3, J5, J7 and J9 indicate that the observed jet streams, as they appear at the cloud level, extend down to depths of thousands of kilometres beneath the cloud level, probably to the region of magnetic dissipation at a depth of about 3,000 kilometres. By inverting the measured gravity values into a wind field, we calculate the most likely vertical profile of the deep atmospheric and interior flow, and the latitudinal dependence of its depth. Furthermore, the even gravity harmonics J8 and J10 resulting from this flow profile also match the measurements, when taking into account the contribution of the interior structure. These results indicate that the mass of the dynamical atmosphere is about one per cent of Jupiter's total mass.

18.
Nature ; 555(7695): 227-230, 2018 03 07.
Article in English | MEDLINE | ID: mdl-29517000

ABSTRACT

Jupiter's atmosphere is rotating differentially, with zones and belts rotating at speeds that differ by up to 100 metres per second. Whether this is also true of the gas giant's interior has been unknown, limiting our ability to probe the structure and composition of the planet. The discovery by the Juno spacecraft that Jupiter's gravity field is north-south asymmetric and the determination of its non-zero odd gravitational harmonics J3, J5, J7 and J9 demonstrates that the observed zonal cloud flow must persist to a depth of about 3,000 kilometres from the cloud tops. Here we report an analysis of Jupiter's even gravitational harmonics J4, J6, J8 and J10 as observed by Juno and compared to the predictions of interior models. We find that the deep interior of the planet rotates nearly as a rigid body, with differential rotation decreasing by at least an order of magnitude compared to the atmosphere. Moreover, we find that the atmospheric zonal flow extends to more than 2,000 kilometres and to less than 3,500 kilometres, making it fully consistent with the constraints obtained independently from the odd gravitational harmonics. This depth corresponds to the point at which the electric conductivity becomes large and magnetic drag should suppress differential rotation. Given that electric conductivity is dependent on planetary mass, we expect the outer, differentially rotating region to be at least three times deeper in Saturn and to be shallower in massive giant planets and brown dwarfs.

19.
Nature ; 555(7695): 220-222, 2018 03 07.
Article in English | MEDLINE | ID: mdl-29517001

ABSTRACT

The gravity harmonics of a fluid, rotating planet can be decomposed into static components arising from solid-body rotation and dynamic components arising from flows. In the absence of internal dynamics, the gravity field is axially and hemispherically symmetric and is dominated by even zonal gravity harmonics J2n that are approximately proportional to qn, where q is the ratio between centrifugal acceleration and gravity at the planet's equator. Any asymmetry in the gravity field is attributed to differential rotation and deep atmospheric flows. The odd harmonics, J3, J5, J7, J9 and higher, are a measure of the depth of the winds in the different zones of the atmosphere. Here we report measurements of Jupiter's gravity harmonics (both even and odd) through precise Doppler tracking of the Juno spacecraft in its polar orbit around Jupiter. We find a north-south asymmetry, which is a signature of atmospheric and interior flows. Analysis of the harmonics, described in two accompanying papers, provides the vertical profile of the winds and precise constraints for the depth of Jupiter's dynamical atmosphere.

20.
Ecohealth ; 15(2): 274-289, 2018 06.
Article in English | MEDLINE | ID: mdl-28963686

ABSTRACT

Does society benefit from encouraging or discouraging private infectious disease-risk mitigation? Private individuals routinely mitigate infectious disease risks through the adoption of a range of precautions, from vaccination to changes in their contact with others. Such precautions have epidemiological consequences. Private disease-risk mitigation generally reduces both peak prevalence of symptomatic infection and the number of people who fall ill. At the same time, however, it can prolong an epidemic. A reduction in prevalence is socially beneficial. Prolongation of an epidemic is not. We find that for a large class of infectious diseases, private risk mitigation is socially suboptimal-either too low or too high. The social optimum requires either more or less private mitigation. Since private mitigation effort depends on the cost of mitigation and the cost of illness, interventions that change either of these costs may be used to alter mitigation decisions. We model the potential for instruments that affect the cost of illness to yield net social benefits. We find that where a disease is not very infectious or the duration of illness is short, it may be socially optimal to promote private mitigation effort by increasing the cost of illness. By contrast, where a disease is highly infectious or long lasting, it may be optimal to discourage private mitigation by reducing the cost of disease. Society would prefer a shorter, more intense, epidemic to a longer, less intense epidemic. There is, however, a region in parameter space where the relationship is more complicated. For moderately infectious diseases with medium infectious periods, the social optimum depends on interactions between prevalence and duration. Basic reproduction numbers are not sufficient to predict the social optimum.


Subject(s)
Communicable Disease Control/organization & administration , Communicable Diseases/epidemiology , Decision Making , Models, Theoretical , Risk Management/organization & administration , Animals , Communicable Disease Control/economics , Cost of Illness , Cost-Benefit Analysis , Economics, Behavioral , Humans , Models, Economic , Motivation , Patient Isolation/economics , Patient Isolation/psychology , Public Health , Risk Assessment , Risk Management/economics , Severity of Illness Index , Vaccination/economics , Vaccination/psychology
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