Built Environment and SARS-CoV-2 Transmission in Long-Term Care Facilities: Cross-Sectional Survey and Data Linkage.

OBJECTIVES: To describe the built environment in long-term care facilities (LTCF) and its association with introduction and transmission of SARS-CoV-2 infection. DESIGN: Cross-sectional survey with linkage to routine surveillance data. SETTING AND PARTICIPANTS: LTCFs in England caring for adults ≥65 years old, participating in the VIVALDI study (ISRCTN14447421) were eligible. Data were included from residents and staff. METHODS: Cross-sectional survey of the LTCF built environment with linkage to routinely collected asymptomatic and symptomatic SARS-CoV-2 testing and vaccination data between September 1, 2020, and March 31, 2022. We used individual and LTCF level Poisson and Negative Binomial regression models to identify risk factors for 4 outcomes: incidence rate of resident infections and outbreaks, outbreak size, and duration. We considered interactions with variant transmissibility (pre vs post Omicron dominance). RESULTS: A total of 134 of 151 (88.7%) LTCFs participated in the survey, contributing data for 13,010 residents and 17,766 staff. After adjustment and stratification, outbreak incidence (measuring infection introduction) was only associated with SARS-CoV-2 incidence in the community [incidence rate ratio (IRR) for high vs low incidence, 2.84; 95% CI, 1.85-4.36]. Characteristics of the built environment were associated with transmission outcomes and differed by variant transmissibility. For resident infection incidence, factors included number of storeys (0.64; 0.43-0.97) and bedrooms (1.04; 1.02-1.06), and purpose-built vs converted buildings (1.99; 1.08-3.69). Air quality was associated with outbreak size (dry vs just right 1.46; 1.00-2.13). Funding model (0.99; 0.99-1.00), crowding (0.98; 0.96-0.99), and bedroom temperature (1.15; 1.01-1.32) were associated with outbreak duration. CONCLUSIONS AND IMPLICATIONS: We describe previously undocumented diversity in LTCF built environments. LTCFs have limited opportunities to prevent SARS-CoV-2 introduction, which was only driven by community incidence. However, adjusting the built environment, for example by isolating infected residents or improving airflow, may reduce transmission, although data quality was limited by subjectivity. Identifying LTCF built environment modifications that prevent infection transmission should be a research priority.

Mind the gap between non-activated (non-aggressive) and activated (aggressive) indoor fungal testing: impact of pre-sampling environmental settings on indoor air readings.

Indoor fungal testing has been within the researchers' scope of interest for more than a century. Various sampling and analysis techniques have been developed over the years, but no testing protocol has been yet standardised and widely accepted by the research and practitioner communities. The diversity in fungal taxa within buildings with varied biological properties and implications on the health and wellbeing of the occupants and the building fabric complicates the decision-making process for selecting an appropriate testing protocol. This study aims to present a critical review of non-activated and activated approaches to indoor testing, with an emphasis on the preparation of the indoor environment prior to sampling. The study demonstrates the differences in the outcomes of non-activated and activated testing through a set of laboratory experiments in idealised conditions and a case study. The findings suggest that larger particles are particularly sensitive to the sampling height and activation, and that non-activated protocols, despite dominating the current literature, can significantly underestimate the fungal biomass and species richness. Therefore, this paper calls for better-defined and activated protocols that can enhance robustness and reproducibility across the research domain focused on indoor fungal testing.

Seating Behaviour of Students before and after the COVID-19 Pandemic: Findings from Occupancy Monitoring with PIR Sensors at the UCL Bartlett Library.

Since the first case of COVID-19 was confirmed in China, social and physical distancing has been promoted worldwide as an effective community mitigation strategy. However, our understanding remains limited regarding how students would resume their activities and use of libraries when the restrictions to manage the spread of coronavirus were lifted. Understanding students' seating behaviour in libraries is required to guarantee that the libraries meet the needs and preferences of students and promote students' health and well-being and satisfaction with the library. This paper aims to explore the changes in the use of study spaces before and after the pandemic. Occupancy data from the UCL Bartlett Library collected at 10-min intervals from motion sensors located underneath desks was used to assess the occupancy within the library and which was then compared to characteristics of the space. This study revealed that the COVID-19 pandemic significantly impacted students' use of the library as well as how much time they spent there. While seats with a good combination of daylight, outdoor view and privacy were in most demand before the pandemic, distance from other students seems to be the priority after the pandemic. Students' seating preferences appear to be also influenced by the position of desk dividers after COVID-19. Future research should focus on assessing and proposing new seating arrangements and developing strategies to promote students' satisfaction with libraries in response to changes in students' seating behaviours.

Evaluation of Daylight Perception Assessment Methods.

Daylight is an important component in maintaining human health and wellbeing and plays a key role in physiological, psychological, and behavioural regulation. Understanding the complexity of daylight perception is vital since the degree of satisfaction with daylight conditions could greatly impact individual mood, behaviour and cognitive performance. This paper aims at (1) presenting an overview of current knowledge on methods for assessing daylight perception and (2) establishing a methodology for assessing daylight perception in the context of cultural background. An experiment was conducted with 50 students who were instructed to select the best and worst seats, describe the best desks' daylight conditions and draw boundary lines between perceived daylit and non-daylit spaces in a library. The study showed that subjective rating and seat preference methods were consistent with actual daylight levels. However, participants' boundary lines did not represent the actual daylight availability in the space. The study suggests that individual daylight perception in the context of cultural background can be assessed using the subjective rating and seat preference methods.

New catechol derivatives of safrole and their antiproliferative activity towards breast cancer cells.

Catechols were synthesized from safrole. Nine derivatives were prepared and assessed for antiproliferative effects using different human cell lines. The in vitro growth inhibition assay was based on the sulphorhodamine dye to quantify cell viability. The derivatives 4-allylbenzene-1,2-diol (3), 4 4-[3-(acetyloxy)propyl]-1,2-phenylene diacetate (6) and 4-[3-(acetyloxy)propyl]-5-nitro-1,2-phenylene diacetate (10) showed higher cytotoxicity than the parent compound 2 in tests performed on two breast cancer cell lines (MCF-7 and MDA-MB-231). The IC50 values of 40.2 ± 6.9 µM, 5.9 ± 0.8 µM and 33.8 ± 4.9 µM, respectively, were obtained without toxicity towards dermal human fibroblast (DHF cells).

Recommendations for building out mosquito-transmitted diseases in sub-Saharan Africa: the DELIVER mnemonic.

In sub-Saharan Africa, most transmission of mosquito-transmitted diseases, such as malaria or dengue, occurs within or around houses. Preventing mosquito house entry and reducing mosquito production around the home would help reduce the transmission of these diseases. Based on recent research, we make key recommendations for reducing the threat of mosquito-transmitted diseases through changes to the built environment. The mnemonic, DELIVER, recommends the following best practices: (i) Doors should be screened, self-closing and without surrounding gaps; (ii) Eaves, the space between the wall and roof, should be closed or screened; (iii) houses should be Lifted above the ground; (iv) Insecticide-treated nets should be used when sleeping in houses at night; (v) houses should be Ventilated, with at least two large-screened windows to facilitate airflow; (vi) Environmental management should be conducted regularly inside and around the home; and (vii) Roofs should be solid, rather than thatch. DELIVER is a package of interventions to be used in combination for maximum impact. Simple changes to the built environment will reduce exposure to mosquito-transmitted diseases and help keep regions free from these diseases after elimination. This article is part of the theme issue 'Novel control strategies for mosquito-borne diseases'.

Synthesis and antitumor activity of diterpenylhydroquinone derivatives of natural ent-labdanes.

Two new compounds 2ß-acetoxy-15-phenyl-(22,25-acetoxy)-ent-labda-8(17), 13(E)-diene (9) and 2ß-hydroxy-15-phenyl-(22,24,26-trimethoxy)-ent-labda-8(17),13(E)-diene (10) have been prepared by an Electrophilic Aromatic Substitution (EAS) reaction between diterpenyl allylic alcohols and 1,4-hydroquinone or 1,3,5-trimethoxybenzene using BF(3).Et(2)O as a catalyst. These compounds, along with a series of natural ent-labdanes 3-8, have been evaluated for their in vitro cytotoxic activities against cultured human cancer cells of PC-3 and DU-145 human prostate cancer, MCF-7 and MDA-MB-231 breast carcinoma and dermal human fibroblasts (DHF). Some compounds displayed inhibition at µM IC(50 )values.

Normal background levels of air and surface mould reserve in English residential building stock: a preliminary study towards benchmarks based on NAHA measurements.

This paper reports results obtained from a surface (both visually clean and dirty/dusty surfaces) and active (aggressive or activated) air testing scheme on 140 residential rooms in England, without visible water damage or mould growth, along with a few rooms with visible mould growth/water damage tested for comparison purposes. The aim was to establish normal background levels of mould in non-water-damaged interiors to benchmark a 'normal' indoor environment, and in turn when there is a need for further investigation, and, possibly, remediation. Air and surface mould was quantified based on the activity of ß-N-acetylhexosaminidase (EC 3.2.1.52; NAHA). The obtained readings showed a log-normal distribution. Ninety-eight percent of the samples obtained from visually clean surfaces were equal to or less than 25 relative fluorescence units (RFU), which is suggested to be the higher bound for the range which can be used as a success criterion for surface cleaning/remediation. Of samples obtained from visually dirty/dusty surfaces, around 98% were below 450 RFU, which is suggested to define the lower-bound for abnormally high levels of mould, rare even on dirty/dusty surfaces. Similarly, around 98% of the air samples were found to have 1700 RFU or below. Values above 1700 RFU are therefore deemed unlikely in a non-problem indoor environment and can be indicative of a possible problem inducing mould growth. The samples with values below 1700 were further divided into three proposed sub-categories. Finally, the obtained RFU values and the suggested benchmarks were compared to those obtained from 17 non-residential indoor environments tested previously in Copenhagen, and the benchmarks that are currently used in Danish national standards, and they were both found to be highly congruent, suggesting that local climate regimes and room functions might not be as influential on indoor mould levels as commonly thought, or that the nuances between England and Denmark in terms of these factors are not strong enough to lead to sizable changes in the typical indoor mould levels in these countries' building stocks.

Synthesis of two new hemisynthetic diterpenylhydroquinones from natural ent-labdanes.

The synthesis and structural determination of two new diterpenylhydroquinones: 2beta-acetoxy-15-phenyl-(22,25-dihydroxy)-ent-labda-8(17),13(E)-diene(1) and 2beta-hydroxy-15-phenyl-(22,25-dihydroxy)-ent-labda-8(17),13(E)-dieneis reported (2). These compounds were obtained by coupling via Electrophilic Aromatic Substitution (EAS) of 1,4-hydroquinone with primary or tertiary allyl alcohol derivatives of the natural ent-labdanes 3 and 4. With this new method, the best results were observed when mixtures of the primary alcohol derivatives 5-6 (26% yield of compound 1) and diol derivatives 9-10 (28% yield of compound 2) were used.

Surface and passive/active air mould sampling: A testing exercise in a North London housing estate.

Despite indoor mould being one of the most common problems in residential properties in the UK, there are not any widely accepted methodologies for its measurement. This paper focusses on this problem of measurement and reports on the findings from a rigorous testing scheme carried out to quantify air and surface mould concentrations and particle counts within 71 rooms from 64 properties in North London, some with and some without visible mould. The aim was to investigate the potential of passive and active air sampling strategies (sampling from still and actively mixed air, respectively) to explain visible mould, and understand how home/room characteristics correlate with the obtained readings. Airborne mould levels were quantified using an Andersen sampler (passively and actively), as well as by a chemical method based on the quantification of the N-acetylhexosaminidase (NAHA) activity (actively), which was also used to quantify surface mould. The mould levels were then correlated against physical characteristics of the tested homes/rooms, collected by means of survey sheets developed as part of this study. The findings did not reveal any independent variable governing all or most of the response variables, but a complex analysis suggested that whether it is a house or a flat could depict mould levels in the air and on the surfaces. It was also shown that a robust testing protocol should combine air and surface based methods, and an active air sampling strategy leads to a more accurate appraisal of airborne mould levels. Finally, the results showed that while there is some correlation between visible mould (and other moisture induced problems such as condensation) and measured air mould concentrations, lack of visible mould within a room does not necessarily mean low air mould concentrations, and thus one should not rely solely on visual inspection.

Oxidative degradations of the side chain of unsaturated ent-labdanes. Part II.

A route for the degradation of the side chain of ent-labdane derivatives has been devised, giving the useful synthon 2beta,12-dihydroxy-13,14,15,16,17-pentanor-ent-labdane-8-one (8). The use of this compound in the preparation of terpenylquinone derivatives shall be reported elsewhere. In addition we have synthesized the compound 2beta,12-diacetoxy-8beta,17-epoxy-13,14,15,16-tetranor-ent-labdane (10), which upon catalytic epoxide ring opening in alkaline or acid media gave rise in all cases to the formation of tricyclicc ompounds.

Oxidative degradations of the side chain of unsaturated ent-labdanes. Part I.

A selective route for the degradation of the unsaturated side chain of ent-labdanes has been devised, giving two useful synthons: 2beta-acetoxy-14,15,17-trinor-ent-labdane-8,13- dione (5) and 2beta-acetoxy-14,15-dinor-ent-labd-8(17)-en-13-one (7), the use of which for the preparation of terpenylquinone derivatives shall be reported elsewhere.

Depsides and triterpenes in Pseudocyphellaria coriifolia (lichens) and biological activity against Trypanosoma cruzi.

The lichen Pseudocyphellaria coriifolia is a species endemic to southern South America. From the lichen thallus, methyl evernate, tenuiorin and three hopane triterpenoids were isolated and identified as the main lichen constituents. Their trypanocidal effects were screened against epimastigotes of Trypanosoma cruzi. The results of the biological test showed that some hopane terpenoids exhibit antiparasitic properties.

Antimicrobial activity of ethyl acetate extract and essential oil from bark of Laurelia sempervirens against multiresistant bacteria / Actividad antimicrobiana del extracto acetato de etilo y aceite esencial de corteza de Laurelia sempervirens contra bacterias multirresistentes

Context: Laurelia sempervirens (R. et P.) Tul., is an evergreen tree that growths in southern Chile, its leaves and bark are used in folk medicine as an infusion. Objective: The antimicrobial activities of the essential oil and ethyl acetate extract obtained from the bark of Laurelia sempervirens were investigated. Materials and methods: Ethyl acetate extract and essential oil were analyzed by GC- mass and the antimicrobial activity was investigated against gram positive and gram negative bacteria. Results: The extract and essential oil showed a strong antimicrobial activity against bacteria such as Acinetobacter baumanii, a relevant world nosocomial pathogen Discussion and conclusion: These findings demonstrate that the ethyl acetate extract and essential oil of L.sempervirens bark have excellent antimicrobial activities and thus have great potential as a source for natural health products.

Contexto: Laurelia sempervirens (R. et P.) Tul., es un árbol de hoja perenne que crece en el sur de Chile, sus hojas y corteza se utilizan en medicina popular como infusión. Objetivo: Investigar la actividad antimicrobiana del aceite esencial y el extracto de acetato de etilo obtenido de la corteza de Laurelia sempervirens. Materiales y métodos: El extracto de acetato de etilo y el aceite esencial se analizaron por GC-masa y la actividad antimicrobiana se analizó contra bacterias gram positivas y gram negativas. Resultados: El extracto y aceite esencial evidenció una fuerte actividad antimicrobiana frente a la bacteria, Acinetobacter baumanii patógeno que causa infecciones nosocomiales de relevancia mundial. Discusión y conclusiones: Estos hallazgos demuestran que el extracto de acetato de etilo y aceite esencial de corteza de L.sempervirens tienen excelentes actividades antimicrobianas y por lo tanto tienen un gran potencial como fuente de productos naturales para la salud.