49 research outputs found

    Interplay of Linker Functionalization and Hydrogen Adsorption in the Metal–Organic Framework MIL-101

    Get PDF
    Functionalization of metal–organic frameworks results in higher hydrogen uptakes owing to stronger hydrogen–host interactions. However, it has not been studied whether a given functional group acts on existing adsorption sites (linker or metal) or introduces new ones. In this work, the effect of two types of functional groups on MIL-101 (Cr) is analyzed. Thermal-desorption spectroscopy reveals that the −Br ligand increases the secondary building unit’s hydrogen affinity, while the −NH2 functional group introduces new hydrogen adsorption sites. In addition, a subsequent introduction of −Br and −NH2 ligands on the linker results in the highest hydrogen-store interaction energy on the cationic nodes. The latter is attributed to a push-and-pull effect of the linkers

    Acknowledgement to reviewers of journal of functional biomaterials in 2019

    Get PDF

    A global experiment on motivating social distancing during the COVID-19 pandemic

    Get PDF
    Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

    A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic

    Get PDF
    The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

    A global experiment on motivating social distancing during the COVID-19 pandemic

    Get PDF
    Significance Communicating in ways that motivate engagement in social distancing remains a critical global public health priority during the COVID-19 pandemic. This study tested motivational qualities of messages about social distancing (those that promoted choice and agency vs. those that were forceful and shaming) in 25,718 people in 89 countries. The autonomy-supportive message decreased feelings of defying social distancing recommendations relative to the controlling message, and the controlling message increased controlled motivation, a less effective form of motivation, relative to no message. Message type did not impact intentions to socially distance, but people’s existing motivations were related to intentions. Findings were generalizable across a geographically diverse sample and may inform public health communication strategies in this and future global health emergencies. Abstract Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

    A global experiment on motivating social distancing during the COVID-19 pandemic

    Get PDF
    Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e. a controlling message) compared to no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly-internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared to the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly-internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing: Controlled motivation was associated with more defiance and less long-term behavioral intentions to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

    Erratum: Author Correction: A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic (Nature human behaviour (2021) 5 8 (1089-1110))

    Get PDF

    Laser reduction of specific microorganisms in the periodontal pocket using Er:YAG and Nd:YAG lasers: a randomized controlled clinical study.

    No full text
    The objective of this study was to evaluate the microbiological and clinical outcomes following nonsurgical treatment by either scaling and root planing, combination of Nd:YAG and Er:YAG lasers, or by Er:YAG laser treatment alone. The study involved 60 patients with generalized chronic periodontitis, randomly assigned into one of three treatment groups of 20 patients. The first group received scaling and root planing by hand instruments (SRP group), the second group received Er:YAG laser treatment alone (Er group), and the third group received combined treatment with Nd:YAG and Er:YAG lasers (NdErNd group). Microbiological samples, taken from the periodontal pockets at baseline and 6 months after treatments, were assessed with PET Plus tests. The combined NdErNd laser (93.0%), followed closely by Er:YAG laser (84.9%), treatment resulted in the highest reduction of all bacteria count after 6 months, whereas SRP (46.2%) failed to reduce Treponema denticola, Peptostreptococcus micros, and Capnocytophaga gingivalis. Full-mouth plaque and bleeding on probing scores dropped after 6 months and were the lowest in both laser groups. The combination of NdErNd resulted in higher probing pocket depth reduction and gain of clinical attachment level (1.99 ± 0.23 mm) compared to SRP (0.86 ± 0.13 mm) or Er:YAG laser alone (0.93 ± 0.20 mm) in 4-6 mm-deep pockets. Within their limits, the present results provide support for the combination of Nd:YAG and Er:YAG lasers to additionally improve the microbiological and clinical outcomes of nonsurgical periodontal therapy in patients with moderate to severe chronic periodontitis

    Photobiomodulation by a 635nm diode laser on peri-implant bone: primary and secondary stability and bone density analysis - a randomized clinical trial

    No full text
    Various procedures in dental implantology are performed to enhance the bone healing process and implant stability. One of these methods can be a low-level laser therapy (LLLT). Objectives. The aim of our study was to evaluate the stabilization (primary and secondary) and bone density in peri-implant zone after LLLT protocol using a 635 nm diode laser. Material and Methods. The research included 40 implants placed in the posterior region of a mandible in 24 patients (8 women and 16 man; age: 46.7 ± 8.7 years). The patients were randomly divided into 2 groups G1 (n=12, 18 implants) and G2 (n=12, 22 implants) according to the treatment procedure; G1 (test): 635 nm laser, with handpiece diameter: 8mm, output power: 100mW, spot area: 0.5024cm2, average power density: 199.04mW/cm2, continuous mode, dose: 4J per point (8J/cm2), time: 40 sec per point, 2 points (irradiation on a buccal and a lingual side of the alveolus/implant), and total energy per session 8J; G2 (control): no laser irradiation. The G1 (test) group's implants were irradiated according to the following protocol: 1 day before surgery, immediately after the surgery and 2, 4, 7, and 14 days after. The total energy after all therapeutic sessions was 48J. The implants stability was measured employing a Periotest device (Periotest Test Value: PTV) (measured immediately after the surgery, 7 days, 2 weeks, 4 weeks, and 2 and 3 months after the surgery) and the bone density using cone-beam computed tomography (grayscale value) (measured immediately after the surgery, 4 weeks and 12 weeks after the treatment). Results. The average implant stability at different time points showed lower PTV value (higher stability) at 2nd and 4th week after 635 nm laser irradiation (G1) compared with a control (G2) group (p<0.01). The secondary stability of the implants after 12 weeks observation was not significantly higher for the laser group in contrast to none-irradiated implants (p>0.05). The mean grayscale value at the apical, middle, and cervical level of the titanium implants showed the reduction of pixel grayscale value after 2 weeks and was lower for the G1 group in contrast to the G2 group (p<0.01). The value of grayscale after 12 weeks was significantly higher at the middle and apical level of the implants in the G1group in contrast to the G2 group (p<0.01). Conclusion. The application of the 635 nm diode laser enhanced secondary implant stability and bone density. However, to assess the impact of the LLLT on peri-implant bone with different bone densities, further well-controlled long-term trials on larger study groups are needed

    Temperature changes and SEM effects of three different implants-abutment connection during debridement with Er:YAG laser: an ex vivo study

    No full text
    The study aimed to evaluate a temperature increase in, and damage to, titanium implants during flapless laser debridement. The study analyzed 15 implants with various implant-abutment connections: a two-piece implant (n = 4) with a screw abutment (IA-Implant-Abutment) and a one-piece implant with a ball type fixture (BTF, n = 4) or fix type fixture (FTF, n = 4). The implants were placed in porcine mandibles 2 mm over a bone crest to imitate a peri-implantitis. The implants were debrided in contact mode for 60 s with a Er:YAG laser at fluence of 9.95 J/cm2 (G1 group: 50 mJ/30 Hz); 19.89 J/cm2 (G2 group: 100 mJ/30 Hz); 39.79 J/cm2 (G3 group: 200 mJ/30 Hz), or a scaler with a ceramic tip (G4 control group: 4W/20 Hz). The temperature was measured with thermocouples at implant and abutment levels. The damage in the titanium surface (n = 3, non-irradiated implants from each type) was assessed using SEM (Scanning Electron Microscopy). The temperature increase at the implant level for the laser was higher at IA in contrast with FTF and BTF. (p < 0.05) The temperature change at the abutment level was lower for the scaler in contrast to Er:YAG laser at FTF. (p < 0.0002) Er:YAG laser didn't increase the temperature by 10 °C at 100 mJ/30 Hz and 50 mJ/30 Hz. Based on SEM analysis, cracks occurred on the surface of two-piece implants and were more pronounced. Cracks and the melting of the titanium surface of two-piece implants cleaned with Er:YAG laser at 100 or 200 mJ were observed. The specimens treated with the ultrasonic scaler with a plastic curette showed the remaining dark debris on the titanium surface. We recommend using Er:YAG laser at 50 mJ/30 Hz during flapless implants debridement
    corecore