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Shared book reading has positive impacts on language development, yet how it is navigated with young dual-language learning (DLL) children is less well understood. This study explored differences in shared reading practices among families raising Spanish/English DLL children with a survey for primary caregivers (n=96) of DLLs between 2-5 years old. Respondents self-reported their household primary language and were categorized into three groups: Spanish primary (SPL), English primary (EPL), or both languages primary (BPL). Respondents answered questions about their own language proficiency, their children’s exposure to English and Spanish, frequency of shared reading in each language, and parent and child language preferences and practices involving the use of both languages during reading. Results indicated that reported household primary language corresponded to language dominance reportedly experienced by the child, and shared reading frequency in each language is impacted by household primary language. Across primary language groups, there were not significant differences in the use of beneficial dialogic reading strategies. Additionally, caregivers’ reported practices around the use of both languages while reading were diverse within each group, and warrant further inquiry. These findings illustrate the importance of contextualizing DLL children’s home language environment in order to better understand their pre-literacy experiences.

Household latrine access generally is not associated with reduced fecal contamination in the environment, but its long-term effectiveness has not been measured. We conducted an environmental assessment nested within the WASH Benefits Bangladesh randomized controlled trial (NCT01590095). We quantified E. coli and fecal coliforms in samples of stored drinking water, child hands, mother hands, soil, and food among a random sample of households from the sanitation and control arms of the trial. Samples were collected during eight quarterly visits approximately 1–3.5 years after intervention initiation. Overall, there were no substantial differences in environmental fecal contamination between households enrolled in the sanitation and control arms. Statistically significant reductions were found in stored water and child hands after pooling across sampling rounds, but the effects were small and not consistent across rounds. In addition, we assessed potential effect modification of intervention effects by follow-up time, season, wealth, community-level latrine density and coverage, population density, and domestic animal ownership. While the intervention had statistically significant effects within some subgroups, there were no consistent patterns of effect modification. Our findings support a growing consensus that on-site latrines are insufficient to prevent fecal contamination in the rural household environment., An on-site latrine and child feces management intervention in rural Bangladesh did not reduce fecal indicator bacteria in the household environment, adding to growing literature on the limitations of latrines as a sanitation solution.

We study relationships between the asymptotic behaviour of a non-elliptic semigroup of holomorphic self-maps of the unit disk and the geometry of its planar domain (the image of the Koenigs function). We establish a sufficient condition for the trajectories of the semigroup to converge to its Denjoy–Wolff point with a definite slope. We obtain as a corollary two previously known sufficient conditions. Ministerio de Economía y Competitividad (Spain) / European Union (FEDER) PGC2018-094215-B-100 Junta de Andalucía (Spain) FQM-133

Background Diarrhea and acute respiratory infection (ARI) are leading causes of death in children. The WASH Benefits Bangladesh trial implemented a multicomponent sanitation intervention that led to a 39% reduction in the prevalence of diarrhea among children and a 25% reduction for ARI, measured 1 to 2 years after intervention implementation. We measured longer-term intervention effects on these outcomes between 1 to 3.5 years after intervention implementation, including periods with differing intensity of behavioral promotion. Methods and findings WASH Benefits Bangladesh was a cluster-randomized controlled trial of water, sanitation, hygiene, and nutrition interventions (NCT01590095). The sanitation intervention included provision of or upgrades to improved latrines, sani-scoops for feces removal, children’s potties, and in-person behavioral promotion. Promotion was intensive up to 2 years after intervention initiation, decreased in intensity between years 2 to 3, and stopped after 3 years. Access to and reported use of latrines was high in both arms, and latrine quality was significantly improved by the intervention, while use of child feces management tools was low. We enrolled a random subset of households from the sanitation and control arms into a longitudinal substudy, which measured child health with quarterly visits between 1 to 3.5 years after intervention implementation. The study period therefore included approximately 1 year of high-intensity promotion, 1 year of low-intensity promotion, and 6 months with no promotion. We assessed intervention effects on diarrhea and ARI prevalence among children p = 0.05; prevalence difference [PD] = −0.027, 95% CI −0.053, 0, p = 0.05). ARI prevalence did not differ between sanitation (21.3%) and control (22.7%) arms (PR = 0.93, 95% CI 0.82, 1.05, p = 0.23; PD = −0.016, 95% CI −0.043, 0.010, p = 0.23). There were no significant differences in intervention effects between periods with high-intensity versus low-intensity/no promotion. Study limitations include use of caregiver-reported symptoms to define health outcomes and limited data collected after promotion ceased. Conclusions The observed effect of the WASH Benefits Bangladesh sanitation intervention on diarrhea in children appeared to be sustained for at least 3.5 years after implementation, including 1.5 years after heavy promotion ceased. Existing latrine access was high in the study setting, suggesting that improving on-site latrine quality can deliver health benefits when latrine use practices are in place. Further work is needed to understand how latrine adoption can be achieved and sustained in settings with low existing access and how sanitation programs can adopt transformative approaches of excreta management, including safe disposal of child and animal feces, to generate a hygienic home environment. Trial registration ClinicalTrials.gov; NCT01590095; https://clinicaltrials.gov/ct2/show/NCT01590095.

Light-induced photocatalytic degradation of ceftiofur sodium (CFS) has been assessed in the presence of plasmonic zinc oxide nanostructures (ZnONSTs), like, ZnO nanoparticles, ZnO nanorods (ZnONRs) and ZnO nanoflowers (ZnONFs). Silver nanoparticles (Ag NPs) loaded ZnO nanostructures (Ag-ZnONSTs) are obtained through seed-assisted chemical reaction followed by chemical reduction of silver. The surface modification of ZnO nanostructures by Ag NPs can effectually alter their optical properties. Further, the surface plasmonic effect of Ag NPs facilitates visible light absorption by ZnONSTs and could improve the photogenerated electron and hole separation, which makes the ZnONSTs a more active photocatalyst than TiO

Functionalization of fillers provides advantages in non-isothermal crystallization of isotactic polypropylene (iPP); therefore, kinetic properties iPP composites filled with alkoxysilane-functionalized titanium dioxide (TiO2) were investigated to understand the role of functional groups. The surface modification of TiO2 nanoparticle was carried out with three different alkoxysilanes: 3-aminopropyltrimethoxysilane (APTMS), 3-chloropropyltrimethoxysilane (CPTMS) and 3-glycidoxypropyltrimethoxysilane (GPTMS); after, composites were prepared 0.5% by weight in iPP. The results of the X-Ray Diffraction and Nuclear magnetic resonance analyses showed the characteristic signals of each chemical species that confirm the success of surface modification of the oxide with alkoxysilanes. The study by Differential scanning calorimetry at different cooling rates allowed to observe that the non-isothermal crystallization of iPP composites is described by Jeziorny’s and Mo’s equations; and that the addition of fillers of TiO2 modified with the alkoxysilanes changed the crystallization process thanks to the functional groups and their interface interactions with the polymer matrix; for example, the presence of CPTMS and GPTMS caused recrystallization of iPP and therefore, increased the crystallization process rate. Finally, the activation energy of the composites varied depending on the alkoxysilane used, since less energy was needed for some cases; derived from better dispersion and that the particles acted as nucleation centers.

In developing countries, death due to diseases caused by fecal-oral ingestion can be avoided by taking action on drinking water issues. Adequate access to water treatment systems to reduce infections is a critical cause. Silver has been used as an antibacterial product, including biomedical applications. Therefore, in this paper, the effect of the chemical speciation of silver from silver-modified zeolite-rich tuffs on the mortality of Escherichia coli (E. coli), Streptococcus faecalis (S. faecalis) and Candida albicans (C. albicans) suspended in aqueous solution was investigated for disinfection purposes. The following aspects were considered to develop the investigation: a) the technique to prepare the modified zeolitic materials, either with ionic silver or silver nanoparticles, which were obtained in two ways: one, with grapefruit extract and the second, by using non-thermal plasma generated in a dielectric barrier discharge reactor of parallel plates; b) the response of the prokaryotes (bacteria) and eukaryote (yeast) microorganisms to disinfectant agents in batch systems; c) the disinfection processes as a function of time to obtain kinetics parameters; and d) the kinetics of the silver release from the silver-modified zeolite-rich tuffs, considering the models of Higuchi and Korsmeyer. The zeolitic materials were characterized by low-vacuum scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The non-thermal plasma reduced ionic silver is more efficient at generating silver compounds with several oxidation states, which are essential during the microbial inhibition process. For the bacterial (E. coli and S. faecalis), the materials with nanoparticles were efficient to inactivate them. However, the yeast (C. albicans) reaches the total inactivation when the zeolitic material contains ionic silver in the crystalline network. The E. coli, S. faecalis and C. albicans survival behavior suspended in aqueous solutions after contact with Ag-modified natural zeolites depends on the chemical speciation of the silver present in these materials, Ag+1 in the case of OAgiZ or nanoparticles of Ago promoted by the grapefruit extract (OAgnpTZ), as well as by non-thermal plasma generated in a dielectric barrier discharge reactor of parallel plates (OAgnpPZ). In general, the concentration of silver in the aqueous solution after the disinfection process cannot exceed the recommended levels established for international organizations. The OAgnpPZ is a potential microbicide agent against E. coli and C. albicans, and the OAgnpTZ for F. faecalis.

Research Findings: Storybooks provide opportunities for children to encounter new words in context and build vocabulary. Storybooks intended for dual-language learners (DLLs) can come in two types ...

BackgroundHousehold-level sanitation interventions have had limited effects on child health or environmental contamination, potentially due to low community coverage. Higher community-level coverage with safely managed sanitation can reduce opportunities for disease transmission.MethodsWe estimated associations between community sanitation coverage, environmental fecal contamination, and child health among 360 compounds in the control arm of the WASH Benefits trial in rural Bangladesh (NCT01590095). In each compound, we enumerated E. coli in environmental samples and recorded the 7-day prevalence of caregiver-reported diarrheal disease and acute respiratory infections (ARI) in children under five. We observed indicators of latrine access and quality among all neighboring compounds within 100m of study compounds. We defined community coverage as the proportion of neighboring compounds with (1) at least one latrine, and (2) exclusively hygienic latrines (improved facility observed to safely contain feces), within both 50m and 100m of study compounds. We assessed effect modification by population density and season.ResultsAdjusted for confounders, study compounds surrounded by 100% coverage of at least one latrine per compound within 50m had slightly lower log10E. coli counts in stored water (Δlog=-0.13, 95% CI -0.26, -0.01), child hand rinses (Δlog=-0.13, 95% CI -0.24, -0.02), and caregiver hand rinses (Δlog=-0.16, 95% CI -0.29, -0.03) and marginally lower prevalence of diarrheal disease (prevalence ratio [PR]=0.82, 95% CI 0.64, 1.04) and ARI (PR=0.84, 95% CI 0.69, 1.03) compared to compounds surrounded by

A career in journalism can be very stressful, as journalists frequently have to deal with uncontrolled situations such as conducting live interviews. Therefore, training is essential during their career, both for the development of communication skills and for the improvement of the real and effective capacity to perform the tasks of their professional activity. The aim of this study was to assess the levels of stress in students before and after a practical training in a professional television set using subjective (State-Trait Anxiety Inventory (STAI) and Likert scale) and objective (salivary cortisol and alpha-amylase) methods. The results indicate that a live interview produces stress in the students as revealed by increased concentrations of cortisol and alpha amylase in saliva. Furthermore, students with lower initial concentrations of these biomarkers obtained better grades in evaluation, suggesting that greater control of anticipatory stress could be associated with a better activity performance.

Memorial days of disasters represent an opportunity to evaluate the progress of recovery. This article uses sentiment analysis (SA) to assess post-disaster recovery on the 10th anniversary of L’Aquila’s earthquake using Twitter data. We have analyzed 4349 tweets from 4 to 10 April 2019 with the hashtag: #L’Aquila that we have obtained from a third-party vendor. The polarity is first defined using a supervised classification based on experts’ rules on post-disaster reconstruction and Grammarly tones. Then, this polarity is compared with the outcome of an unsupervised classification based on the pre-trained SA machine learning algorithm developed by MonkeyLearn. We have found a significant negative assessment of the post-disaster recovery process in L’Aquila. About 33.1% of the tweets had a negative polarity, followed by 29.3% tweets with a neutral polarity, 28.7% with positive polarity, and 8.9% unrelated to the anniversary. Further analysis of the tweets confirms that after 10 years, the reconstruction is still ongoing and that criticism of the recovery reported in the literature is also found in the tweets. Based on our analysis, the critical day to collect most of the data is the anniversary’s exact day. Tweets from citizens and/or news agencies, which are more likely to express the reality experienced, are therefore more useful in understanding recovery than tweets from government officials and/or governmental institutions. From the total 4349 tweets, we can state that 2488 (57%) were correctly classified by the pre-trained SA machine learning algorithm developed by MonkeyLearn, while 1861 (43%) were misclassified. It means an overall accuracy (ACC) of 57% and a misclassification rate of 43% by the algorithm. We argue that our results have the potential to serve as a benchmark that can be used to compare other post-disaster recovery processes using the same Twitter-based SA on their anniversaries.

The use of mannequins to practice different clinical procedures in undergraduate students complies with the 3R principle (Replacement, Reduction, Refinement) without affecting professional competencies. However, commercial solutions are often expensive and therefore, not available for many schools. The main aim of this study was to describe the development and validation of an economical Do-It-Yourself mannequin for jugular blood collection from dogs. The use of the mannequin was evaluated by (1) assessment of the opinion of students and experts and (2) by conducting a pilot study where salivary biomarkers of stress were determined in students and dogs. The costs of the materials needed for the mannequin confection were less than 60 Euros and it was easily built in less than 1 h. The mannequin was very well accepted and scored by both, students and experts, being mostly liked a lot and considered it to be very useful for the practices (Scored 8, 9 or 10/10). Students that could first practice with the mannequin reported a self-perceived higher level of confidence and had lower levels of alpha-amylase in saliva after the procedure. Overall, the mannequin enables the initiation of blood sampling skills in agreement with 3R principles and is easy to perform, economically affordable and sustainable. This model could be adapted to other vein simulations and animal species, and has the potential to help students deal with stressful situations such as taking blood samples from a live animal.

In this paper we introduce the family of spaces $RM(p,q)$, $1\leq p,q\leq +\infty$. They are spaces of holomorphic functions in the unit disc with average radial integrability. This family contains the classical Hardy spaces (when $p=\infty$) and Bergman spaces (when $p=q$). We characterize the inclusion between $RM(p_1,q_1)$ and $RM(p_2,q_2)$ depending on the parameters. For $1, Comment: 31 pages

This study examined the association between the sleep environment and sleep disturbances in 44 low-income Latinx youth. Participants reported an average of 2.10 past-week ambient sleep disruptions....

During the 2012–2016 drought in La Guajira, Colombia, child mortality rates rose to 23.4 out of 1000. Most of these children belonged to the Wayuu indigenous community, the largest and one of the most vulnerable in Colombia. At the municipal level, this study found a significant positive correlation between the average child mortality rate and households with a monthly income of less than USD 100, the number of people without access to health insurance, being part of the indigenous population, being illiterate, lacking sewage systems, living in rural areas, and large households with members younger than 5 years old and older than 65 years old. No correlation was found with households without access to a water source. The stepwise regression analysis showed that households with a monthly income of less than USD 100, no members older than 65 years old, but several children younger than 5 years old, account for 90.4% of the child mortality rate. This study concludes that, if inhabitants had had better incomes or assets, as well as an adequate infrastructure, they could have faced the drought without the observed increase in child mortality.

El complejo volcánico Cayambe representa una potencial amenaza para poblaciones que basan su economía en la floricultura. En este trabajo, se presenta: 1) modelar espacialmente escenarios de erupción del volcán, 2) modelar espacialmente el potencial impacto de estos escenarios de riesgos por afectación de lahares y de ceniza; y 3) evaluar los impactos socioeconómicos de escenarios de erupción modelados por caída de ceniza mediante un análisis estadístico de simulaciones numéricas de escenarios eruptivos y zonas de afectación por lahares tomadas del nuevo mapa de amenazas del Cayambe. Así se determinó que espesores de ceniza de 20 a 50 mm serían el principal problema cubriendo el 81.46% de la superficie con pérdidas que ascienden los 300 millones de dólares en plantas e invernaderos. En el caso de lahares las pérdidas se darían en los suelos y se estiman pérdidas de 45 millones de dólares en el caso de lahares primarios y 15 millones de dólares en caso de lahares secundarios.Los resultados obtenidos en las simulaciones tienen mejor nivel de detalle que los obtenidos en años anteriores por la información cartográfica disponible del sector y las herramientas computacionales utilizadas; los mismos que concuerdan con los depósitos del Cayambe y pueden ser manejados para la toma de decisiones en beneficio de las poblaciones afectadas, considerando que una erupción del volcán Cayambe merece una atención especial por su alto impacto socioeconómico local y nacional por ser las exportaciones de flores un rubro importante para el país.

El volcán Guagua Pichincha es considerando el tercer volcán más peligroso en el Ecuador continental, y representa una amenaza potencial para la población expuesta. En esta investigación se modela, mediante un análisis estadístico de simulaciones numéricas, la dispersión y caída de ceniza al 75% de probabilidad de ocurrencia para zonificar la amenaza volcánica a través de escenarios eruptivos y datos censales con ayuda de herramientas computacionales. Así, se estimó la cantidad de población rural-urbana y categorías de uso de suelo que se verían afectadas. Estos escenarios de impacto tendrían diferentes efectos en función de los espesores máximos esperados, que van desde los 5 mm para el escenario con un índice de explosividad volcánica 2 (VEI, por sus siglas en inglés) y de 150 mm de acumulación de ceniza para el escenario con un VEI5; incrementando significativamente el número de poblados, zonas urbanas y categoría de uso de suelo afectados en cada escenario planteado. Los mapas obtenidos muestran, para el evento VEI2 (menor), siete parroquias con un impacto bajo, mientras que para el escenario VEI5 (extenso–muy extenso) se tendría un impacto alto en 33 parroquias, incluida la capital del Ecuador.

The 2020 Zagreb earthquake occurred on Sunday 22 March 2020. This earthquake was the first that happened during the lockdown imposed by governments to stop spreading the COVID-19. This fact makes the event interesting as a multi-hazard phenomenon. The lockdown made it not possible to deploy an earthquake reconnaissance mission. Therefore, it was necessary to undertake a remote mission supported by the monitoring and analysing social media (SM) platforms, such as Twitter and Instagram. This paper presents details and analysis of this monitoring and how it may help understand the impacts of an earthquake. In our work, we first identified the hashtags related to the event. Through the LastQuake app, we obtained the intensity reports from affected people and comments and pictures useful for damage assessment. The team obtained 59,246 tweets posted between the 20th March and the 30th April 2020 and 31,911 comments from LastQuake app users written on the day of the earthquake. Images from posts and comments were used for remote assessment of damage in buildings. Sentiment analysis (SA) was applied to tweets and comments related to the event to assess emergency management during the relief phase after the earthquake. Our work shows that only a limited number of pictures collected through social media were suitable for damage assessment of individual buildings. However, they were still useful as a proxy estimation of damages in some areas of Zagreb and surroundings. We also found SA supported by machine learning a valuable method to assess and identify critical aspects of the emergency and early recovery post-disaster phases. Applying SA we identified the most affected areas, the damages in the non-structural elements in hospitals, the support of collaborative networks for the evacuation of patients and the role of Ministers in the early recovery.

In this paper we characterize the boundedness, compactness, and weak compactness of the integration operators Tg(f)(z) = ˆ z 0 f(w)g (w) dw acting on the average radial integrability spaces RM(p, q). For these purposes, we develop different tools such as a description of the bidual of RM(p, 0) and estimates of the norm of these spaces using the derivative of the functions, a family of results that we call Littlewood–Paley type inequalities. Ministerio de Economía y Competitividad, Spain, and the European Union (FEDER) PGC2018-094215-13-100 Junta de Andalucía, Spain FQM133 Junta de Andalucía, Spain FQM-104

Summary The North West African Atlantic Margin with the MSGBC basin area covering Mauritania, Senegal, the Gambia, Guinea Bissau and Guinea Conakry being one of the hottest areas in Africa currently, a new modern and continuous 3D dataset finalized early 2020, now allows to correlate a full suite of regional interpretation, well correlation and basin modelling base values to be extended and tested for spectral signature of proposed source rocks, anomaly response of known reservoirs, full scale traps and volumes, and possible migration paths; all in high resolution 3D across the margin. After this study is completed, the results set a well calibrated, modern baseline for the shelf edge and deepwater hydrocarbon exploration offshore the MSGBC basin, providing play fairways and structural details, evaluated for maturity and trap volumes with the future addition of further acquired ultra-deepwater seismic 3D surveys.

Author(s): Aghanim, N; Akrami, Y; Ashdown, M; Aumont, J; Baccigalupi, C; Ballardini, M; Banday, AJ; Barreiro, RB; Bartolo, N; Basak, S; Battye, R; Benabed, K; Bernard, JP; Bersanelli, M; Bielewicz, P; Bock, JJ; Bond, JR; Borrill, J; Bouchet, FR; Boulanger, F; Bucher, M; Burigana, C; Butler, RC; Calabrese, E; Cardoso, JF; Carron, J; Challinor, A; Chiang, HC; Chluba, J; Colombo, LPL; Combet, C; Contreras, D; Crill, BP; Cuttaia, F; De Bernardis, P; De Zotti, G; Delabrouille, J; Delouis, JM; DI Valentino, E; DIego, JM; Dore, O; Douspis, M; Ducout, A; Dupac, X; Dusini, S; Efstathiou, G; Elsner, F; Enslin, TA; Eriksen, HK; Fantaye, Y; Farhang, M; Fergusson, J; Fernandez-Cobos, R; Finelli, F; Forastieri, F; Frailis, M; Fraisse, AA; Franceschi, E; Frolov, A; Galeotta, S; Galli, S; Ganga, K; Genova-Santos, RT; Gerbino, M; Ghosh, T; Gonzalez-Nuevo, J; Gorski, KM; Gratton, S; Gruppuso, A; Gudmundsson, JE; Hamann, J; Handley, W; Hansen, FK; Herranz, D; Hildebrandt, SR; Hivon, E; Huang, Z; Jaffe, AH; Jones, WC; Karakci, A; Keihanen, E; Keskitalo, R; Kiiveri, K; Kim, J; Kisner, TS | Abstract: In the original version, the bounds given in Eqs. (87a) and (87b) on the contribution to the early-time optical depth, (15,30), contained a numerical error in deriving the 95th percentile from the Monte Carlo samples. The corrected 95% upper bounds are: τ(15,30) l 0:018 (lowE, flat τ(15, 30), FlexKnot), (1) τ(15, 30) l 0:023 (lowE, flat knot, FlexKnot): (2) These bounds are a factor of 3 larger than the originally reported results. Consequently, the new bounds do not significantly improve upon previous results from Planck data presented in Millea a Bouchet (2018) as was stated, but are instead comparable. Equations (1) and (2) give results that are now similar to those of Heinrich a Hu (2021), who used the same Planck 2018 data to derive a 95% upper bound of 0.020 using the principal component analysis (PCA) model and uniform priors on the PCA mode amplitudes.

Background: Reusing wastewater for irrigation is a longstanding practice that enhances crop yields and improves climate resilience. Without treatment, however, wastewater contains harmful pathogens and chemicals. Reuse of untreated wastewater has been shown to be harmful to the health of nearby communities, but the routes of exposure are unknown and do not appear to be occupational. Some routes occur throughout entire communities, such as food contamination. Other routes may be spatially dependent, such as spread by domestic animals or through aerosolization. Objectives: To examine whether those wastewater exposure routes with a spatial dependency affect health, we estimated the risks of diarrheal disease in children under age 5 associated with living near wastewater canals, while adjusting for potential individual- and household-level confounders. Methods: We conducted three surveys over 1 y in the Mezquital Valley, Mexico, to measure diarrhea in children. The distance between each participating household and a wastewater canal was measured using GPS coordinates. The association between proximity and diarrhea was estimated with a multilevel logistic regression model accounting for spatial autocorrelation. Results: A total of 564 households completed one to three surveys, resulting in 1,856 survey observations of 646 children. Children living 100m from a canal had 45% lower odds of diarrhea than those living within 10m of a canal, and children living 1000m away had 70% lower odds of diarrhea [100m vs. 10m adjusted odds ratio (OR)=0.55, 95% credible interval (CI): 0.33, 0.91; 1000m vs. 10m adjusted OR=0.30, 95% CI: 0.11, 0.82]. Discussion: The estimated decline in diarrheal prevalence with household distance from a canal persisted after controlling for occupational exposure. Identifying the specific routes of exposure that drive this relationship will help identify which interventions, such as upstream treatment, can reduce health risks for entire communities where wastewater exposure occurs. https://doi.org/10.1289/EHP6443

In this note, we provide an elementary proof of a fundamental result in the theory of semigroups of holomorphic self-maps of the unit disc. Namely, regular fixed points of a semigroup are in one-to-one correspondence with regular points of its infinitesimal generator. As far as we know, there is no complete proof of this fact in the literature.

Let $\mathbb D$ be the unit disc in $\mathbb C$ and let $f:\mathbb D \to \mathbb C$ be a Riemann map, $\Delta=f(\mathbb D)$. We give a necessary and sufficient condition in terms of hyperbolic distance and horocycles which assures that a compactly divergent sequence $\{z_n\}\subset \Delta$ has the property that $\{f^{-1}(z_n)\}$ converges orthogonally to a point of $\partial \mathbb D$. We also give some applications of this to the slope problem for continuous semigroups of holomorphic self-maps of $\mathbb D$., Comment: 15 pages