Improving the light collection efficiency of silicon photomultipliers through the use of metalenses

Metalenses are optical devices that implement nanostructures as phase shifters to focus incident light. Their compactness and simple fabrication make them a potential cost-effective solution for increasing light collection efficiency in particle detectors with limited photosensitive area coverage. Here we report on the characterization and performance of metalenses in increasing the light collection efficiency of silicon photomultipliers (SiPM) of various sizes using an LED of 630 nm, and find a six to seven-fold increase in signal for a 1.3×1.3 mm² SiPM when coupled with a 10-mm-diameter metalens manufactured using deep ultraviolet stepper lithography. Such improvements could be valuable for future generations of particle detectors, particularly those employed in rare-event searches such as dark matter and neutrinoless double beta decay

Socioeconomic environment and survival in patients after ST-segment elevation myocardial infarction (STEMI): a longitudinal study for the City of Vienna

Objectives: This study investigates the relationship between socioeconomic environment (SEE) and survival after ST-segment elevation myocardial infarction (STEMI) separately for women and men in the City of Vienna, Austria. Design: Hospital-based observational data of STEMI patients are linked with district-level information on SEE and the mortality register, enabling survival analyses with a 19-year follow-up (2000-2018). Setting: The analysis is set at the main tertiary care hospital of the City of Vienna. On weekends, it is the only hospital in charge of treating STEMIs and thus provides representative data for the Viennese population. Participants: The study comprises a total of 1481 patients with STEMI, including women and men aged 24-94 years. Primary and secondary outcome measures: Primary outcome measures are age at STEMI and age at death. We further distinguish between deaths from coronary artery disease (CAD), deaths from acute coronary syndrome (ACS), and other causes of death. SEE is proxied via mean individual gross income from employment in each municipal district. Results: Results are based on Kaplan-Meier survival probability estimates, Cox proportional hazard regressions and competing risk models, always using age as the time scale. Descriptive findings suggest a socioeconomic gradient in the age at death after STEMI. This finding is, however, not supported by the regression results. Female patients with STEMI have better survival outcomes, but only for deaths related to CAD (HR: 0.668, 95% CIs 0.452 to 0.985) and other causes of deaths (HR: 0.627, 95% CIs 0.444 to 0.884), and not for deaths from the more acute ACS. Conclusions: Additional research is necessary to further disentangle the interaction between SEE and age at STEMI, as our findings suggest that individuals from poorer districts have STEMI at younger ages, which indicates vulnerability in regard to health conditions in these neighbourhoods

People and plant: Learning with Adi community on ethnomedicinal practices and conservation in Arunachal Pradesh, India

74-82Local plant species have been in use in variety of ethnomedicinal practices from the time immemorial among the people of various communities for treating various human diseases. This paper reports about the plant species used by Adi community in curing various human diseases and ailments. A study was conducted during 2008-2009 and further refined in succeeding years with the 12 purposively selected traditional knowledge holders (TKHs) of Adi tribe of East Siang district, Arunachal Pradesh, India. Data were collected using combined approaches of personal interview, participant observations and transect walks. It was observed that with Shannon-Weaver diversity index 2.73, there were 39 local plant species belonging to 25 plant families and used as ethnomedicinal practices by the TKHs. Most of the species (17) were used by Adi TKHs with their green leaf parts followed by root and fruits (5 each) to develop ethnomedicinal formulations. Out of these, several species namely Leucas aspera (Willd.) Link.; Plumeria rubra L.; Catharanthus roseus (L.) G. Don; Solanum torvum Swartz; Solanum khasianum C.B. Clarke; Oroxylum indicum (L.) Benth.ex Kurze; and Tinospora cordifolia (Thunb.) Miers) were found in use by Adis against asthma, bronchitis, cough, sinusitis, diabetes, malaria, typhoid and jaundice. The Adi TKHs maintain a rich cultural ethics, govern by their own world-view in continuing ethnomedicinal practices, and harvesting the species from various land use systems with the aim to sustain biodiversity and associated practices. The key findings indicated that, plant species used as ethnomedicines for some of the diseases and ailments by the Adi TKHs, can be undertaken for the long-term trial to find some natural remedies against few human diseases, including search of immune enhancer against COVID-19, provided TKHs of Adi community are partnered in ethically and culturally appropriate manner.&nbsp

People and plant: Learning with Adi community on ethnomedicinal practices and conservation in Arunachal Pradesh, India

Local plant species have been in use in variety of ethnomedicinal practices from time immemorial among the people of various communities for treating various human diseases. This paper reports about the plant species used by Adi community in curing various human diseases and ailments. A study was conducted during 2008-2009 and further refined in succeeding years with the 12 purposively selected traditional knowledge holders (TKHs) of Adi tribe of East Siang district, Arunachal Pradesh, India. Data were collected using combined approaches of personal interview, participant observations and transect walks. It was observed that with Shannon-Weaver diversity index 2.73, there were 39 local plant species belonging to 25 plant families and used as ethnomedicinal practices by the TKHs. Most of the species (17) were used by Adi TKHs with their green leaf parts followed by root and fruits (5 each) to develop ethnomedicinal formulations for treating a range of diseases and ailments. Out of these, most of the species [(e.g., Leucas   aspera (Willd.) Link.; Plumeria rubra L.; Catharanthus roseus (L.) G. Don; Solanum  torvum Swartz; Solanum  khasianum C. B. Clarke; Oroxylum  indicum (L.) Benth. ex Kurze; and Tinospora  cordifolia (Thunb.) Miers)] were found in use by Adis against asthma, bronchitis, cough, sinusitis, diabetes, malaria, typhoid and jaundice. The Adi TKHs holders maintain a rich cultural ethics, govern by their own world-view in continuing ethnomedicinal practices, and harvesting the species from various land use systems with the aim to sustain biodiversity and associated practices. The key findings indicated that, plant species used as ethnomedicines for some of the diseases and ailments by the Adi TKHs, can be undertaken for the long-term trial to find some natural remedies against few human diseases, including search of immune enhancer against COVID-19,  provided TKHs of Adi community are partnered in ethically and culturally appropriate manner.

Providing a computing environment for a high energy physics workshop

Although computing facilities have been provided at conferences and workshops remote from the host institution for some years, the equipment provided has rarely been capable of providing for much more than simple editing and electronic mail. This report documents the effort involved in providing a local computing facility with world-wide networking capability for a physics workshop so that we and others can benefit from the knowledge gained through the experience

Salt Dependence of the Tribological Properties of a Surface-Grafted Weak Polycation in Aqueous Solution

The nanoscopic adhesive and frictional behaviour of end-grafted poly[2-(dimethyl amino)ethyl methacrylate] (PDMAEMA) films (brushes) in contact with gold- or PDMAEMA-coated atomic force microscope tips in potassium halide solutions with different concentrations up to 300 mM is a strong function of salt concentration. The conformation of the polymers in the brush layer is sensitive to salt concentration, which leads to large changes in adhesive forces and the contact mechanics at the tip–sample contact, with swollen brushes (which occur at low salt concentrations) yielding large areas of contact and friction–load plots that fit JKR behaviour, while collapsed brushes (which occur at high salt concentrations) yield sliding dominated by ploughing, with conformations in between fitting DMT mechanics. The relative effect of the different anions follows the Hofmeister series, with I − collapsing the brushes more than Br − and Cl − for the same salt concentration