Correlates to psychological distress in frail older community-dwellers undergoing lockdown during the COVID-19 pandemic.

BACKGROUND: This study identifies correlates of the lockdown's psychological distress in frail older community-dwellers (Catalonia, Spain). METHODS: Participants from a community frailty intervention program, with a comprehensive geriatric assessment within the 12-months pre-lockdown and COVID-19 free during the first pandemic wave (March-May 2020), underwent a phone assessment past the lockdown to assess COVID-19-related emotional distress (DME) as well as other sociodemograhic, clinical and psychosocial factors. RESULTS: Of the 94 frail older adults (age = 82,34 ± 6,12 years; 68,1% women; 38,3% living alone), 84,9% were at risk of experiencing moderate-to-high psychological distress, according to the backward stepwise logistic regression model obtained (χ2 = 47,007, p < 0,001, Nagelkerke R2 = 0,528), based on the following factors: absence of depressive symptoms before lockdown (OR = 0,12, p = 0,014, 95%CI[0,023-0,647]), not carrying out leisure activities during lockdown (OR = 0,257, p = 0,023, 95%CI[0,079-0,832]) and currently experiencing high malaise due to COVID-19 situation (OR = 1,504, p < 0,001, 95%CI[1,241-1,822]). DISCUSSION: These findings suggest that it is necessary to favour a prior overall health status and to empower frail older community-dwellers in the use of a broad repertoire of coping strategies in the face of adversity to foster mental health and keep at bay the potential emotional impact of the situation generated by the COVID pandemic.

Experimental Assessment of the Transmission Performance of Step Index Polymer Optical Fibers Using a Green Laser Diode.

Large-core polymer optical fiber (POF) links have limitations in capacity and reach due to the fibers' high modal dispersion and attenuation. Most of these links use red laser diodes, even though the attenuation spectrum of poly(methyl methacrylate) (PMMA), the basic polymer used to manufacture these fibers, has a lower minimum in the green region. Therefore, we set out to explore the potential use of green light in transmission systems, comparing the performances of three step-index polymer optical fibers (SI-POFs) with different numerical apertures. We obtained measurements of intensity distribution, frequency response and bit error rate (BER), as functions of fiber length. We have also compared the fibers' frequency responses with red and green light for a few selected lengths. Our results confirm that SI-POFs attenuate less in response to green light, which can increase their length. This advantage is partially counterbalanced by a slightly higher dispersion that limits the capacity of the high-aperture fibers, particularly at relatively short lengths. Our conclusions are critical to understanding SI-POF behavior and to designing thorough SI-POF models that can aid the design of POF-based links for different scenarios.

Application of a glass fertilizer in sustainable tomato plant crops.

BACKGROUND: Glass frits with a P2 O5 /K2 O ratio equal to 0.65 and different concentrations of SiO2 (6.5-56.0 wt%), CaO (0-5.1 wt%) and Al2 O3 (0-14.6 wt%) have been prepared and analysed as potential glass fertilizers (GF). RESULTS: P2 O5 and K2 O were leached primarily within the first 5 days but the total amount was dependent on the SiO2 /Al2 O3 ratio of the glass frit. Sustained P2 O5 and K2 O leaching for more than 40 days could be obtained if the glass frit contained more than 7% Al2 O3 . A final glass frit composition (29% SiO2 , 5% CaO, 7% Al2 O3 , 30% P2 O5 , 25% K2 O) was selected and used in an experimental tomato crop of 1 ha area, where one half was fertilized with an NPK conventional fertilizer and the other half with the GF fertilizer. CONCLUSION: After harvesting the tomato crops, the GF fertilizer was found to result in a higher yield than the NPK conventional fertilizer: 59980 kg and 74 360 kg for NKP and GF, respectively. The general characteristics of the harvested tomato fruits and leaves were similar in the two cases and the differences fell within statistical error. No differences in any of the soil characteristics were detected as a result of the use of GF. © 2018 Society of Chemical Industry.