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Twenty-six genera and 34 species of early Miocene Indian shallow-marine ostracodes were examined for taxonomy and paleobiogeography. A new genus Paractinocythereis and new species Costa ponticulocarinata were described. Early Miocene Indian ostracode fauna shows strong affinity to Eocene–Miocene Eastern and Western Tethyan ostracode faunas and Miocene–Recent Indo-Pacific ostracode fauna, supporting the Hopping Hotspot Hypothesis that the Tethyan biodiversity hotspot has shifted eastward through Arabia to Indo-Australian Archipelago (IAA) together with concomitant biogeographic shifts of the Tethyan elements. The result also indicated an inverse westward distributional shift in a genus. It is important to note that Paleogene and Miocene shallow marine ostracodes from the IAA region remain poorly investigated, and more fossil ostracode data are needed to better test the Hopping Hotspot Hypothesis.
The near-infrared reflectance spectra of Pluto and its satellites are rich with diagnostic absorption bands of ices of CH4, N2, CO, H2O, and an incompletely identified ammonia-bearing molecule. Following years of investigation of the spectra of Pluto and Charon with ground-based telescopes, NASA’s New Horizons spacecraft obtained spectral maps of these bodies and three small satellites on its passage through the system on July 14, 2015, showing the distribution of these ices, as well as a colored, non-ice component. Spectral modeling mapped the distribution of the various ices and showed their abundance and mixing details in relationship to regions of differing surface elevation, albedo, and geologic structure. Additionally, owing to their greatly different degrees of volatility, the ices of Pluto are distributed in patterns responsive to Pluto’s climatic changes on both short and long terms. The surface of Charon is dominated spectrally by H2O ice with one or more ammoniated compounds, and three of the four very small satellites show both H2O ice and the ammonia signature.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
The trade of live parrots is a threat to wild populations but is understudied. Madagascar is home to three parrot species listed on CITES Appendix II: Coracopsis nigra, Coracopsis vasa and Agapornis canus. Prior to this study there were no data on the ownership of parrots in Madagascar. We therefore aimed to investigate the extent of the domestic pet trade in this group. Our objectives were to quantify the prevalence, spatial extent, and timing of ownership. We collected data in July and August 2016 in nine urban towns across Madagascar, using semi-structured household surveys (n = 440). We found that the ownership of pet parrots is widespread in time and space; 37% (95% CI 26–48%) of interviewees had seen, and 8% (95% CI 3–13%) had owned, a Coracopsis sp. Fewer interviewees (4.5% of all interviewees) had seen A. canus in captivity, and only one individual reported having previously owned an A. canus. We estimate that 1,290 Coracopsis spp. individuals were held in captivity in the towns surveyed, in the 1.5 years prior to our interviews. It is likely that much of this ownership is illegal, although we did not examine this explicitly. Additional research is needed to determine whether current extraction rates are sustainable. This study adds to a growing body of evidence that the domestic regulation of the trade of wild species is not being addressed adequately in Madagascar.
Non-native species impact tropical ecosystems, but the role of different anthropogenic disturbances on the success of non-natives remains unclear, especially in island tropical forests. We sought to understand the influence of anthropogenic habitat degradation and disturbance on non-native plant species in Madagascar. Specifically, we evaluated how densities of non-native species of woody shrub (Lantana camara), climber (Mucuna pruriens) and tree (Mangifera indica, Albizia lebbeck, Tamarindus indica) varied with forest habitat degradation and by disturbance type. We surveyed 60400 m2, recording 482 instances of disturbance and 903 non-native plants in and around the Ankarana National Park. Non-native plant densities were higher in degraded than primary forest. Within degraded forest, densities of non-native trees increased with disturbance. Tree densities correlated with extent of tree damage only in Tamarindus indica, never correlated with extent of tree removal, and always correlated with proximity to roads and trails. Our results suggest roads and trails have relatively greater importance in facilitating the success of non-native tree species than structural changes to habitat. In contrast, densities of Lantana camara and Tamarindus indica did not correlate with any measured type of disturbance; other unmeasured or historical factors may be more important drivers of these smaller, faster-reproducing species.
We have mapped the southern galaxies NGC 613, 1313, 1433, 1566, 1672 and 2442 in the 12CO(J = 1 → 0) transition with the 15-m Swedish European Submillimetre Telescope (SEST). The sample is based on galaxies previously observed in radio continuum with the Molonglo Observatory Synthesis Telescope (MOST). Strong emission is seen from the barred galaxies NGC 613 and NGC 2442 and from the active galaxies NGC 1566 and 1672. The weakest emission was from NGC 1433, while the Sd spiral NGC 1313 was not detected.
The role of wild meat for subsistence or as a luxury good is debated. We investigated the role of wild meat in food security in Madagascar, where consumption is poorly understood in urban areas and at regional scales. Using semi-structured interviews (n = 1339 heads-of-households, 21 towns), we aimed to: (1) quantify the amount and purpose of, (2) understand the drivers of, and (3) examine changes in wild meat consumption. Few respondents preferred wild meat (8 ± 3%) but most had eaten it at least once in their lifetime (78 ± 7%). Consumption occurred across ethnic groups, in urban and rural settings. More food insecure areas reported higher rates of wild meat consumption in the 6–8 months prior to interviews. Consumption was best explained by individual preferences and taboos. Less than 1% of respondents had increased consumption during their lifetimes. Wild meat prices showed no change from 2005–2013. Most consumption involved wild pigs and smaller-sized animals, though they were consumed less in the years following the 2009 coup. These data illustrate the differences between urban and rural communities, the occasions in which wild meat is used a source of food security, and provide evidence that some taxa are not hunted sustainably in Madagascar.
Marine, freshwater and terrestrial ecosystems face increasing anthropogenic threats that are exacerbated by the ecological connectivity between realms; integrated land-sea management (ILSM) is a framework that can help address this connectivity. However, gaps in our knowledge regarding ILSM remain. This study reviewed 108 relevant studies to understand how ILSM is being utilized. Summarized are: (1) characteristics of integrated land-sea programs; (2) recommendations made from the literature for program planning, implementation and management; (3) how applied programs have been planned, implemented and managed; and (4) recommendations for undertaking ILSM. It was found that applied programs did not often adhere to the strategies recommended by theoretical papers. Applied programs were less likely than theoretical papers to specifically name the land-sea connection, over 50% did not apply a framework or governance approach, many did not include key stakeholders, and over 80% listed at least one conflict or hurdle that decreased program success. This study highlighted the difficulties of undertaking ILSM given the high number of stakeholders, government agencies and experts involved. Based on the findings, recommendations for future ILSM programs are provided.
Overexploitation is a significant threat to biodiversity, with live capture of millions of animals annually. An improved understanding of live capture of primates is needed, especially for Madagascar's threatened lemurs. Our objectives were to provide the first quantitative estimates of the prevalence, spatial extent, correlates and timing of lemur ownership, procurement methods, within-country movements, and numbers and duration of ownership. Using semi-structured interviews of 1,093 households and 61 transporters, across 17 study sites, we found that lemur ownership was widespread and affected a variety of taxa. We estimate that 28,253 lemurs have been affected since 2010. Most lemurs were caught by owners and kept for either short (≤ 1 week) or long (≥ 3 years) periods. The live capture of lemurs in Madagascar is not highly organized but may threaten several Endangered and Critically Endangered species.
Background and objective: Measurement of central blood volumes (CBV), such as global end-diastolic volume (GEDV) and right ventricular end-diastolic volume (RVEDV) are considered appropriate estimates of intravascular volume status. However, to apply those parameters for preload assessment in mechanically ventilated patients, the influence of tidal volume (TV) and positive endexpiratory airway pressure (PEEP) on those parameters must be known. Methods: In 13 mechanically ventilated piglets, the effect of low (10 mL kg−1) and high (20 mL kg−1) TVs on CBV was investigated in absence and presence of PEEP (0 and 15 cmH2O). GEDV, RVEDV, right heart (RHEDV) and left heart end-diastolic volume (LHEDV) were measured by thermodilution. Blood flow on the descending thoracic aorta measured with an ultrasonic flow-probe served to determine stroke volume (SV). Measurements were performed during baseline conditions, after volume loading with previously extracted haemodilution blood (20 mL kg−1) and following haemorrhage (30 mL kg−1). Results: Application of PEEP decreased GEDV and SV significantly (P < 0.05). Augmenting TV did not reduce GEDV systematically, but significantly reduced SV (P < 0.05). Changes in ventilator settings only influenced RVEDV following volume loading (P < 0.05). RHEDV and LHEDV decreased following application of PEEP, but only RHEDV decreased after augmenting TV at baseline and following volume loading. Correlation of SV with parameters of CBV was r = 0.487 (P < 0.01) for GEDV, r = 0.553 (P < 0.01) for RVEDV, r = 0.596 (P < 0.01) for RHEDV and r = 0.303 (P < 0.01) for LHEDV. Conclusion: Application of PEEP decreases CBV and SV. Augmenting TV reduces SV but not CBV. There is a moderate correlation between parameters of CBV and cardiac performance.
Background and objective: The efficacy of the Trendelenburg position, a common first step to treat suspected hypovolaemia, remains controversial. We evaluated its haemodynamic effects on cardiac preload and performance in patients after cardiac surgery.
Methods: Twelve patients undergoing mechanical ventilation of the lungs who demonstrated left ventricular ‘kissing papillary muscles’ by transoesophageal echocardiography, thus suggesting hypovolaemia, were positioned 30° head down for 15 min immediately after cardiac surgery. Cardiac output by thermodilution, central venous pressure, pulmonary artery occlusion pressure, left ventricular end-diastolic area by transoesophageal echocardiography and intrathoracic blood volume by thermo- and dye dilution were determined before, during and after this Trendelenburg manoeuvre.
Results: Trendelenburg's manoeuvre was associated with increases in central venous pressure (9 ± 2 to 12 ± 3 mmHg) and pulmonary artery occlusion pressure (8 ± 2 to 11 ± 3 mmHg). The intrathoracic blood volume index increased slightly (dye dilution from 836 ± 129 to 872 ± 112 mL m−2; thermodilution from 823 ± 129 to 850 ± 131 mL m−2) as did the left ventricular end-diastolic area index (7.5 ± 2.1 to 8.1 ± 1.7 cm2 m−2), whereas mean arterial pressure and the cardiac index did not change significantly. After supine repositioning, the cardiac index decreased significantly below baseline (3.0 ± 0.6 versus 3.5 ± 0.8 L min−1 m−2) as did mean arterial pressure (76 ± 12 versus 85 ± 11 mmHg), central venous pressure (8 ± 2 mmHg) and pulmonary artery occlusion pressure (6 ± 4 mmHg). The intrathoracic blood volume index and left ventricular end-diastolic area index did not differ significantly from baseline.
Conclusions: Trendelenburg's manoeuvre caused only a slight increase of preload volume, despite marked increases in cardiac-filling pressures, without significantly improving cardiac performance.
We have done a comparative study of carbon-doped GaN and undoped GaN utilizing photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies in order to investigate deep levels involved in yellow luminescence (YL) and red luminescence (RL). When the GaN was excited by above-bandgap light, red luminescence (RL) centered at 1.82 eV was the dominant below-gap PL from undoped GaN, but carbon-doped GaN below-gap PL was dominated by yellow luminescence (YL) centered at 2.2 eV. When exciting PL below the band-gap with 2.4 eV light, undoped GaN had a RL peak centered at 1.5 eV and carbon-doped GaN had a RL peak centered at 1.65 eV. PLE spectra of carbon-doped GaN, detecting at 1.56 eV, exhibited a strong, broad excitation band extending from about 2.1 to 2.8 eV with an unusual shape that may be due to two or more overlapping excitation bands. This RL PLE band was not observed in undoped GaN. We also demonstrate that PL spectra excited by below gap light in GaN films on sapphire substrates are readily contaminated by 1.6−1.8 eV and 2.1−2.5 eV chromium-related emission from the substrate. A complete characterization of the Cr emission and excitation bands for sapphire substrates enables the determination of the excitation and detection wavelengths required to obtain GaN PL and PLE spectra that are free of contributions from substrate emission.
We have done a comparative study of carbon-doped GaN and undoped GaN utilizing photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies in order to investigate deep levels involved in yellow luminescence (YL) and red luminescence (RL). When the GaN was excited by above-bandgap light, red luminescence (RL) centered at 1.82 eV was the dominant below-gap PL from undoped GaN, but carbon-doped GaN below-gap PL was dominated by yellow luminescence (YL) centered at 2.2 eV. When exciting PL below the band-gap with 2.4 eV light, undoped GaN had a RL peak centered at 1.5 eV and carbon-doped GaN had a RL peak centered at 1.65 eV. PLE spectra of carbon-doped GaN, detecting at 1.56 eV, exhibited a strong, broad excitation band extending from about 2.1 to 2.8 eV with an unusual shape that may be due to two or more overlapping excitation bands. This RL PLE band was not observed in undoped GaN. We also demonstrate that PL spectra excited by below gap light in GaN films on sapphire substrates are readily contaminated by 1.6-1.8 eV and 2.1-2.5 eV chromium-related emission from the substrate. A complete characterization of the Cr emission and excitation bands for sapphire substrates enables the determination of the excitation and detection wavelengths required to obtain GaN PL and PLE spectra that are free of contributions from substrate emission.
We present real time observations of the interaction of dislocations in heteroepitaxial strained layers using a specially modified ultrahigh vacuum transmission electron microscope equipped with in-situ deposition capabilities. These observations have led to delineation of the regime of epilayer thickness and composition where dislocation interactions result in blocking of the propagating threading segment. It is found that both the blocking probability as well as the magnitude of the dislocation interaction force are strongly dependent on the Burgers vectors of the dislocations involved, with the greatest effects observed when the Burgers vectors of the two dislocations are parallel with respect to each other. Frame-by-frame analysis of the motion of the dislocation threading segment during interaction is used to extract the magnitude of the interaction stresses as a function of both the level of heteroepitaxial strain and the dislocation geometry. Finally, by continuing growth following observations of blocking during annealing, we find that blocked dislocations are likely to remain in that configuration until substantial additional heteroepitaxial stresses are incorporated into the layer. These results have direct relevance to the successful integration of strained layer heterostructures into electronic device applications. This is because blocked threading segments result in the introduction of undesired band gap states, enhance impurity diffusion, modify surface morphology and act to limit the dislocation density reductions achievable in graded buffer structures.
The photoluminescence (PL) of GaN grown on SiC is studied as a function of etch depth for two types of etches, photoelectrochemical and chemically assisted ion beam. It is found that as the etch proceeds deeper toward the substrate, the PL exhibits an increasing blue-shift and an increase in emission intensity of the donor acceptor pair band, which indicates increasing biaxial compressive stress and increasing impurity concentration near the substrate. The PL spectra of the dry etched GaN tended to have slightly higher intensities than comparably wet etched GaN.