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Presents information on a study which discussed the growth of gallium indium (In) arsenic/In phosphide by metalorganic vapor-phase epitaxy by capacitance-voltage measurements against temperature and frequency. Sample preparation; Effect of frequency on the apparent profile in terms of the dynamic behavior of the traps; Modelization of the frequency-dependent apparent profile.

Tropospheric delay is one of the deleterious factors limiting the accuracy of the precise Global Navigation Satellite Systems positioning. The value of delay depends on the path through which a signal has to follow in the subsurface layers of the atmosphere. Tropospheric delay models are developed to overcome this limitation. Among them one can find UNB, TropGrid or IGGtrop models. In this paper, we adjusted the UNB3m model to the actual meteorological parameters from Europe. A new model was called UNBe.eu covering the EGNOS augmentation system area. The use of meteorological observations helped us to decrease the bias for more than 70% of reference radio sounding locations. Still, 30% of reference sites depicted a lack of any improvements of the ZTD estimation with regard to the newly established model. Therefore, this study puts forward a need for a deeper investigation of the discussed issue. [ABSTRACT FROM PUBLISHER]

Investigates the dark current mechanisms in indium gallium arsenide/indium phosphide double-heterostructure photodiodes grown by metalorganic chemical vapor deposition. Process of electron emission; Information on the exponential behavior of the dark current.

GaInAsP-InP buried ridge structure lasers emitting at 1.3 μm have been fabricated on material grown completely by low pressure metalorganic chemical vapor deposition. These lasers have low threshold (11 mA), exhibit linear (kink-free) light-current characteristics up to high powers (10 mW/facets), and can be operated at high temperatures (70 °C). Excellent uniformity over 10 cm2 has been obtained, and an external quantum efficiency of 60% for two faces has been measured. [ABSTRACT FROM AUTHOR]

Continuous wave operation of 1.57-μm distributed feedback lasers fabricated on material grown by two-step low-pressure metalorganic chemical vapor deposition growth process is reported for the first time. Room-temperature continuous wave threshold currents as low as 60 mA have been measured for devices with cavity length of 300 μm and stripe width of 5 μm. Single longitudinal mode operation at fixed mode was obtained under the continuous wave condition, in the temperature range 9-90 °C, with the wavelength shift of 0.9 Å/°C. A stop band of 25 Å in which no resonance mode emission existed, was observed in the output spectrum of the distributed feedback laser. [ABSTRACT FROM AUTHOR]

High-rate GNSS has been proven effective in characterising waveforms and co-seismic displacements due to medium-to-strong natural earthquakes. No application focused on small magnitude events like shallow anthropogenic earthquakes, where displacements and noise have the same order of magnitude. We propose a procedure based on proper signal detection and filtering of the position and velocity time series obtained from high-rate (10 Hz) GNSS data processing with two intrinsically different approaches (Precise Point Positioning and variometry). We tested it on five mining tremors with magnitudes of 3.4-4.0, looking both at event detection and its kinematic characterisation. Here we show a high agreement, at the level of 1 s, between GNSS and seismic solutions for the earthquake first epoch detection. Also, we show that high-rate multi-constellation (GPS + Galileo) GNSS can reliably characterise low-magnitude shallow earthquakes in terms of induced displacements and velocities, and, including their peak values, respectively, at the level of very few millimetres and 1-2 cm/s, paving the way to the routine use of GNSS-seismology for monitoring human activities prone to cause small earthquakes and related potential damages., (© 2023. The Author(s).)

COVID-19 has disproportionately affected the Latinx community, leading to heightened economic instability and increased mortality/morbidity. Frontline community health workers ( promotoras ) have played an integral role in serving low-income Latinx immigrant communities, disseminating health information to this vulnerable community while also facing heightened risks to their own health and wellbeing. This study explores the impact of the pandemic on Latinx communities and the promotoras that serve them, examining how the stresses and inequities the pandemic wrought might be mitigated. Promotoras ( N = 15, all female) were recruited from a local health agency in Santa Ana, CA and completed a semi-structured interview about their experiences during COVID-19. Qualitative analyses demonstrated that the pandemic substantially affected the daily lives both of community members, via economic challenges, limited access to reliable pandemic-related information, and psychological and social stress, and of promotoras, via changes to the nature of their work and psychological and social stress. Promotoras perceived that these harms might be mitigated by providing for economic and material needs in the community, and that promotoras can be fortified to continue serving the community through self-care and psychosocial healing practices. According to promotoras, the Latinx community needs economic and material resources to overcome COVID-19 related stressors. Additionally, promotoras may benefit from programming to preserve mental and physical health in the wake of new stressors. Lending greater support to promotoras within the agencies in which they are nested may enable them to be more successful in fulfilling their mission and sustaining their own health.

We compared serum concentrations of zinc, chromium, and iron in dogs with cancer to those of normal dogs. Dogs with lymphoma (n = 50) and osteosarcoma (n = 52) were evaluated. Dogs with lymphoma had significantly lower (P = .0028) mean serum zinc concentrations (mean +/- SD; 1.0 +/- 0.3 mg/L) when compared to normal dogs (1.2 +/- 0.4 mg/L). Dogs with osteosarcoma also had lower mean serum zinc concentrations (1.1 +/- 0.4 mg/L), but this difference was not significant (P = .075). Serum chromium concentrations were significantly lower in dogs with lymphoma (2.6 +/- 2.6 microg/L, P = .0007) and osteosarcoma (2.4 +/- 3.1 microg/L, P = .0001) compared to normal dogs (4.7 +/- 2.8 microg/L). Serum iron concentrations and total iron-binding capacity were significantly lower in dogs with lymphoma (110.8 +/- 56.7 microg/dL, P < .0001, and 236.6 +/- 45.6 microg/dL, P < .0001, respectively) and osteosarcoma (99.6 +/- 49.3 microg/dL, P < .0001, and 245.0 +/- 43.8 microg/dL, P = .0011, respectively) when compared to normal dogs (175.1 +/- 56.7 microg/dL and 277.1 +/- 47.4 microg/dL). Mean ferritin concentration was significantly higher in dogs with lymphoma (1291.7 +/- 63.0 microg/L) than in normal dogs (805.8 +/- 291.1 microg/L, P < .0001) and dogs with osteosarcoma (826.5 +/- 309.2 microg/L, P < .0001). Further investigation is needed to explore the clinical significance of these mineral abnormalities in dogs with cancer.