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The mesosphere/lower thermosphere (MLT, 80–100 km) region is an important boundary between Earth's atmosphere below and space above and may act as a sensitive indicator for anthropogenic climate change. Existing observational and modeling studies have shown the middle atmosphere and the MLT is cooling and contracting because of increasing greenhouse gas emissions. However, trend analyses are highly sensitive to the time periods covered, their length, and the measurement type and methodology used. We present for the first time the linear and 11‐year solar cycle responses in the meteor ablation altitude distributions observed by 12 meteor radars at different locations. Decreasing altitudes were seen at all latitudes (linear trends varying from −10.97 to −817.95 m dec−1), and a positive correlation with solar activity was seen for most locations. The divergence of responses at high latitudes indicates an important and complex interplay between atmospheric changes and dynamics at varying time scales. Plain Language Summary: High up in our atmosphere lies the mesosphere/lower thermosphere region (80–100 km); an important transition zone between the atmosphere below and space above. Existing studies indicate that this region is changing (cooling and contracting) in response to increasing greenhouse gas emissions, quite unlike the net warming we see near the surface. However these trend studies are often highly sensitive to choice and length of time period covered, and the methodology and type of measurements used. Here we present for the first time a self‐consistent methodology applied to 12 different meteor radar station datasets located at a diverse range of latitudes. We looked at changes in the mean peak altitude of individual meteoroid detections, and found decreasing peak altitudes at all locations examined (linear trends varying from −10.97 to −817.95 m decade−1) consistent with a global cooling and contracting of the upper atmosphere. We also examined the response to the 11‐year solar cycle and found a positive correlation with solar activity (i.e., increased meteoroid peak altitudes during solar maximum, and vice versa) for low and mid‐latitude locations. However we found an anti‐correlation at high latitudes suggestive of an important and complex interplay between atmospheric changes and dynamics at varying time scales. Key Points: Use of geographically diverse meteor radar peak detection altitudes to assess long‐term and 11‐year solar cycle (SC) trends in mesopause regionThe altitude of observed peak meteor height has decreased over time at all locations, regardless of latitude and data setPositive correlation at low‐ and mid‐latitude locations with the 11‐year SC, but more complex response at high‐latitudes [ABSTRACT FROM AUTHOR]

Atmospheric gravity waves (GWs) are key drivers of the atmospheric circulation, but their representation in general circulation models (GCMs) is challenging, leading to significant biases in middle atmospheric circulations. Unresolved GW momentum transport in GCMs must be parameterized, but global directional GW observations are needed to constrain this. Here we present an 18‐year climatology of directional stratospheric GW momentum flux (GWMF) from global AIRS/Aqua 3‐D satellite observations during 2002 to 2019. Striking hemispheric asymmetries are found at high latitudes, including dramatic reductions and reversals of GWMF during sudden stratospheric warmings. During Southern Hemisphere winter, a lateral convergence of GWMF toward 60°S is found that has no Northern Hemisphere counterpart. In the tropics, we find that zonal GWMF in AIRS measurements is strongly modulated by the semiannual oscillation (SAO) but not the quasi‐biennial oscillation (QBO). Our results provide guidance for future GW parameterizations needed to resolve long‐standing biases in GCMs. Plain Language Summary: Gravity waves (GWs) are traveling waves that can occur in geophysical fluid environments subject to the gravitational force. In the Earth's atmosphere, GWs transport momentum that helps to drive the atmospheric circulation, especially in the middle atmosphere. But for numerical weather and climate models, accurately simulating GWs has proven very challenging because of a lack of GW observations, leading to significant model biases. Here we present an 18‐year climatology of GW observations near 40‐km altitude for 2002 to 2019. For the first time, we present multidecadal global measurements of directional GW momentum flux derived from 3‐D satellite observations from National Aeronautics and Space Administration's (NASA's) AIRS instrument. We find that during Southern Hemisphere winter, GWs travel laterally toward 60°S each year. This is significant because most models underestimate GW momentum near 60°S and do not typically include lateral propagation in their parameterizations. In the tropical stratosphere, we find no modulation of GWs in AIRS observations by the quasi‐biennial oscillation (QBO). This is consistent with the hypothesis that GW‐QBO interactions occur at shorter vertical wavelengths, which are invisible to AIRS. Our results will help to guide future GW parameterizations, leading to more accurate atmospheric simulations and ultimately better forecasts of weather and climate. Key Points: Directional stratospheric gravity wave momentum flux (GWMF) is derived from global 3‐D AIRS/Aqua satellite observations from 2002 to 2019Dramatic reductions and reversals of high‐latitude GWMF are seen during SSWs; in the tropics the SAO modulates the AIRS GWMF but not the QBOA lateral convergence of wintertime GWMF toward 60°S occurs each year that has no counterpart in the Northern Hemisphere [ABSTRACT FROM AUTHOR]

Satellite observations show that there is a wintertime hotspot of gravity wave activity, located mainly over the ocean, around 60°S in the stratosphere. However, the sources of the gravity waves making up this hotspot are varied and complex and remain unclear. Here we use radiosonde observations from 11 Antarctic stations and selected small islands close to 60°S to examine the horizontal directional pseudo‐momentum flux and energy density distributions of upward propagating gravity waves in the lower stratosphere. This paper shows, for the first time, that short vertical wavelength gravity waves in the lower stratosphere clearly propagate meridionally toward 60°S during the winter months. This result supports previous studies that show that this belt of gravity wave activity over the ocean is contributed to by wave sources outside 60°S. Plain Language Summary: Atmospheric gravity waves are buoyancy waves, where the restoring force is gravity, which can have horizontal wavelengths from a few tens to hundreds of kilometers. They can be generated by a variety of sources including wind flow over mountains and storms. Over the Drake Passage and out to the east around 60°S, a large hotspot of gravity waves has been observed in the wintertime stratosphere using satellite observations. The sources for this gravity wave hotspot are unclear as it mainly located over the open ocean. In this paper radiosonde observations are used to examine, for the first time, the directional variation in short vertical wavelength gravity waves close to 60°S in the lower stratosphere. It is found that during the winter months there is a meridional convergence of gravity waves toward 60°S, implying that the gravity wave sources of the hotspot are in fact be outside this region. Key Points: This paper provides evidence of a winter time convergence of gravity waves and their momentum flux toward 60°SThis is the first time this has been observed for short vertical wavelength waves in the lower stratosphere [ABSTRACT FROM AUTHOR]

Monoamine uptake inhibitors are common treatments for depression; however, the therapeutic efficacy of these drugs varies widely. Two factors that are commonly linked to clinical outcome are age and serotonin transporter ( SERT) genotype. Mouse models provide powerful tools to study consequences of age and genotype on antidepressant-like efficacy; however, to date, systematic studies of this nature are lacking. Here, we used the tail suspension test ( TST), a preclinical assay for antidepressant efficacy, to gain insight into age and SERT genotype dependency of immobility time in the TST under control conditions (saline injection) and in response to the tricyclic antidepressant, desipramine ( DMI). Immobility after saline injection in juvenile, adolescent, adult, mature adult and middle-aged mice (postnatal days 21, 28, 90, 210 and 300, respectively) significantly increased with age; however, the rate of increase was slower for SERT null (−/−) mice than for wild-type (+/+) or heterozygote (+/−) mice. Desipramine reduced immobility across ages and SERT genotypes. Middle-aged, but not adult, SERT−/− mice were significantly more sensitive to DMI than age-matched SERT+/+ or SERT+/− mice. Desipramine was less potent in middle-aged SERT+/+ and SERT+/− mice than in adult SERT+/+ or SERT+/− mice. Regardless of age, DMI's maximal effects were greater in SERT−/− mice than in SERT+/+ or SERT+/− mice. These results show that immobility time in the TST varies as a function of age and SERT genotype, underscoring the utility of the TST as a potential model to examine age- and SERT genotype-dependent influences on antidepressant response. [ABSTRACT FROM AUTHOR]

Here, we report the identification of 69 tracks in approximately 250 cm2 of aerogel collectors of the Stardust Interstellar Dust Collector. We identified these tracks through Stardust@home, a distributed internet-based virtual microscope and search engine, in which > 30,000 amateur scientists collectively performed >9 × 107 searches on approximately 106 fields of view. Using calibration images, we measured individual detection efficiency, and found that the individual detection efficiency for tracks > 2.5 μm in diameter was >0.6, and was >0.75 for tracks >3 μm in diameter. Because most fields of view were searched >30 times, these results could be combined to yield a theoretical detection efficiency near unity. The initial expectation was that interstellar dust would be captured at very high speed. The actual tracks discovered in the Stardust collector, however, were due to low-speed impacts, and were morphologically strongly distinct from the calibration images. As a result, the detection efficiency of these tracks was lower than detection efficiency of calibrations presented in training, testing, and ongoing calibration. Nevertheless, as calibration images based on low-speed impacts were added later in the project, detection efficiencies for low-speed tracks rose dramatically. We conclude that a massively distributed, calibrated search, with amateur collaborators, is an effective approach to the challenging problem of identification of tracks of hypervelocity projectiles captured in aerogel. [ABSTRACT FROM AUTHOR]

A means of deriving a disturbance index reflecting forest use history is demonstrated here to establish a disturbance gradient and enable comparison of different forest areas within and across individual forests. Detailed reference is made to Kakamega Forest in western Kenya for which a long-term time series has been established, although the study is spread to four further forests in Kenya and Uganda. A wide variety of sources are drawn upon for spatially resolved data that are integrated in a geographic information system. Three indices are derived: for commercial disturbance, local disturbance, and forest cover change. Results show a wide range of disturbance values (from low to heavy) for the research sites within Kakamega Forest, while results for Budongo and Mabira Forest sites show low and moderate levels, respectively. Correlations of low disturbance levels with nature or national reserves appear to be marked, while a correlation of disturbance with differing management authority is also suggested with Kenya Wildlife Service achieving the lowest disturbance levels. Results from the index are reviewed against other means of estimating disturbance with the conclusion that disturbance evaluations should be both spatially resolved and long-term in nature. [ABSTRACT FROM AUTHOR]

Soil compaction can affect seedling root development by decreasing oxygen availability and increasing soil strength. However, little quantitative information is available on the compaction tolerances of non-crop native species. We investigated the effects of soil compaction on establishment and development of two New Zealand native species commonly used in restoration programmes; Cordyline australis (Agavaceae) (cabbage tree) a fleshy rooted species, and Leptospermum scoparium (Myrtaceae) (manuka) a very finely rooted species. Seedlings were grown in a range of soil compaction levels in growth cabinet experiments. Low levels of soil compaction (0.6 MPa) reduced both the number and speed of C. australis seedlings penetrating the soil surface. In contrast, L. scoparium seedlings showed improved establishment at an intermediate compaction level. Root and shoot growth of both species decreased with increasing soil strength, with L. scoparium seedlings tolerating higher soil strengths than did C. australis. Despite these results, soil strength accounted for only a small amount of variation in root length ( R2 < 0.25), due to greater variability in growth at low soil strengths. Soil strengths of 0.6 MPa are likely to pose a barrier to C. australis regeneration. This is consistent with adaptation to organic and/or soft, waterlogged soils. Active intervention may be necessary to establish C. australis from seed on many sites previously in farmland. [ABSTRACT FROM AUTHOR]

Coronary heart disease (CHD) is the leading cause of mortality in the United States. Hypertension, diabetes mellitus, hypercholesterolemia, and smoking have all been directly related to CHD. Obesity is on the rise in the United States and has also been associated with CHD. This review clearly establishes obesity as an independent risk factor for CHD as demonstrated by the Framingham Heart Study, Nurses' Health Study, Buffalo Health Study, and the Cancer Prevention Study II. Morbid obesity was found to correlate with a significant risk of mortality from CHD, especially in young men. Prevention of obesity, and therefore reduction in risk from cardiovascular disease, is paramount in the management of obesity. New approaches to behavioral, medical, and surgical management of obesity are reviewed, including thalidomide, an antiangiogenic agent. A primary and secondary prevention model details a multidisciplinary approach to reducing risk in obesity. [ABSTRACT FROM AUTHOR]

Variation in response to the Guignard pictate test may be detected within wild British populations of Brassica oleracea L. subsp. oleracea. Plants with the greatest reaction are the least frequent. In different seasons, individuals react differently to the test, possibly in response to temperature fluctuations. In B. oleracea the picrate test is perhaps responding to allyl derivatives of the glucosinolate sinigrin; HCN was not detected. [ABSTRACT FROM AUTHOR]

The possible involvement of flavour volatiles in the resistance of Brassica oleracea L. seedlings to cabbage downy mildew (Peronospora parasitica (Pers. ex Fr.) Fr.) was investigated using seedlings of a number of commercial Brassica oleracea cultivars. Flavour volatiles are primarily released as a result of tissue damage in brassicas. Only one cultivar tested was resistant to the disease and its tissue maccrates yielded the greatest concentration of volatiles. One of these compounds, allyl isothiocyanate, proved to be highly toxic to the pathogen and was produced in much greater concentrations in maccrates of cotyledon than first leaf tissue. The ability of seedlings to produce ally! isothiocyanate in large amounts following tissue damage may inhibit the growth of Peronospora parasitica in resistant seedlings. Wild populations of Brassica oleracea L. subsp. oleracea (wild cabbage) were also tested for disease resistance, and the highest proportions of resistant seedlings were found in those populations containing high levels of flavour volatiles. The longest established wild populations possessed the highest average concentrations of flavour volatiles, and it is suggested that selective breeding has resulted in a reduction in the amounts of these compounds in cultivated forms. This change may be a contributory factor towards the lack of resistance shown by modern cultivars. [ABSTRACT FROM AUTHOR]

The performance of a Rotman lens, which forms fixed beams at 0°, ±15° and ±30°, is augmented using liquid crystal phase shifters to simultaneously steer each beam by up to ±7.5°. Measured results are used to demonstrate that the true time delay property of the antenna and voltage controlled phase shifters can be exploited to provide continuously scanned beams with full coverage over an angular range of ±37.5°, and with operation over the band 6–10 GHz. [ABSTRACT FROM AUTHOR]

Background: Depression is associated with substantial morbidity and mortality in cirrhosis, but is underdiagnosed and undertreated., Aims: Using the Mini International Neuropsychiatric Interview (MINI) as a gold-standard, to determine prevalence, predictors, and outcomes of depression, and to develop a screening nomogram for use in cirrhosis patients., Methods: Cirrhotic outpatients 18-80 years of age, not on anti-depressants, were consecutively recruited from liver clinics at three tertiary care hospitals. Baseline health-related quality of life (HRQoL) and frailty were determined by the chronic liver disease questionnaire, EQ-VAS, Clinical Frailty Scale and Fried Frailty Criteria. Depression was identified using the MINI and participants were followed up to 6 months to determine unplanned hospitalization/death., Results: Of 305 patients, 62% were male; mean age 55(10) years; mean MELD 12.5(5), 61% Child Pugh B/C. Prevalence of depression 18% by MINI. Patients with depression had lower baseline HRQoL and higher frailty scores. Five independently predictive factors were used to develop a clinical nomogram for the diagnosis of clinical depression. These included three Hospital Anxiety and Depression Screening tool variables: "I have lost interest in my appearance" (adjusted odds ratio [aOR] 2.2, P = 0.006), "I look forward with enjoyment to things" (aOR 2.0, P = 0.02), "I feel cheerful" (aOR 2.8, P = 0.002), and two demographic variables: younger age (aOR 0.92, P = 0.001) and not being married or in a common-law relationship (aOR 0.30, P = 0.008)., Conclusions: Depression is common in patients with cirrhosis. It has a significant impact on HRQoL and functional status. The developed clinical nomogram is promising for the rapid screening of depression in patients with cirrhosis., (© 2018 John Wiley & Sons Ltd.)