Pool Environment Research Articles

Research and Development of Cellar Pool Environmental Monitoring System Based on NB-IOT and Cloud Platform

NB-IOT and cloud platform technology are used to monitor the cellar pool environment, which is difficult to collect by hand. Under the zigbee self-organizing network, the system collects the parameters of the terminal nodes distributed in each cellar pool through a coordinator, and then sends them to the ali cloud internet of things platform for display and control through the nb-IOT communication module. Experiments show that the system can display the environment data of the cellar pool in real time and open the execution device outside the threshold range, which proves the practicability and convenience of the system.

Exploring the diversity of microeukaryotic communities in New England tide pools

Though historically understudied, due in large part to most species being uncultivable, microbial eukaryotes (i.e. protists) are abundant and widespread across diverse habitats. Recent advances in molecular techniques, including metabarcoding, allow for the characterization of poorly known protist lineages. This study surveys the diversity of SAR (Stramenopila, Alveolata, and Rhizaria), a major eukaryotic clade that is estimated to represent about half of all eukaryotic diversity. SAR lineages use varied metabolic strategies like mixotrophy in dinoflagellates (Alveolata), parasitism in apicomplexans (Alveolata) and labyrinthulids (Stramenopila), and life cycle stages that include encystment and attachment (e.g. in ciliates, Alveolata) to survive in highly dynamic habitats. Using metabarcoding primers designed specifically to target a portion of the 18S small subunit ribosomal RNA (SSU-rRNA) gene of SAR lineages, we compare protist community composition from tide pools in Acadia National Park, Maine, USA. We characterize over 500 lineages, here operational taxonomic units (OTUs), many of which are found abundant in the tide pool environment. We also find that communities vary by month sampled and exhibit patterns by size (i.e. macro-, micro-, and nano-sized). Taken together, these data allow us to further catalog protist diversity in extreme environments (e.g. those subject to extreme fluctuations in temperature and salinity during tidal cycles). Such data are critical in the explorations of biodiversity patterns among microorganisms on our rapidly changing planet.

Motivasi Berenang Ditinjau Dari Usia

This study discusses swimming motivation in terms of age in Surakarta. The goal to be achieved is to determine the amount of intrinsic and extrinsic motivation of someone who does swimming in a swimming pool in the Solo area. This research is a descriptive study with one variable, namely: motivation, the population used are visitors to the Tirtomoyo Manahan swimming pool. Sampling using incidental sampling technique, namely the technique of determining the sample based on chance, that is, anyone who incidentally meets the researcher. The number of samples in this study were 84 people. The instrument used to collect data uses a psychological scale, to analyze the collected document, the researcher uses qualitative descriptive analysis techniques.The results showed that a person has intrinsic and extrinsic motivation in doing swimming. The motivation varies according to the age of each sample. Intrinsic factors in the age category of children (5 years-11 years) because they want to play and are happy with water games, in the adolescent age category (12 years-25 years) as a lifestyle and add friends and fill spare time, in the adult category (26 years-45 years) as a supporter of a healthy lifestyle and improve health status, while in the elderly category (46 years - 65 years) as one of the sports for health therapy, namely asthma therapy and bone health. The extrinsic factor of the resource persons, on average, chose a swimming pool, namely because the Tirtomoyo swimming pool is in the middle of the city and has complete facilities and a clean pool environment.

Surveillance of Legionella pneumophila: Detection in Public Swimming Pool Environment.

The bacterium Legionella pneumophila is a ubiquitous microorganism naturally present in water environments. The actual presence of this opportunistic premise plumbing pathogen in recreational swimming pools and hot tubs in the northwestern part of Croatia has not been investigated. This study aimed to analyze the presence of the opportunistic pathogen L. pneumophila in public swimming pool water in Primorje-Gorski Kotar County (N = 4587) over a four-year period (2018-2021). Additionally, the second aim was to investigate the connection between the presence of L. pneumophila and pool water physicochemical parameters using mathematical predictive models. The presence of L. pneumophila was detected in six pool samples. Five positive samples were found in the water of indoor hot tubs filled with fresh water, and one positive sample in an outdoor recreational saltwater pool. A predictive mathematical model showed the simultaneous influence of chemical parameters dominated by the temperature in saltwater and freshwater pools, as well as the significant influence of free residual chlorine and trihalomethanes. Our results pointed out that keeping all physicochemical parameters in perfect harmony is necessary to reach the best disinfection procedure and to avoid the optimum conditions for L. pneumophila occurrence.

Petrogenesis of Holocene siliceous sinters from the Los Geysers geothermal field, northern Trans-Mexican Volcanic Belt

Sinters are siliceous rocks precipitated from geothermal waters typically formed in continental volcanic provinces, where heat flux is significant and deep source fluids become silica-rich due to water-rock interaction processes. Research on this type of rock is useful to elucidate key aspects on the reconstruction of hydrothermal processes operating during their deposition. This study aimed to understand the petrogenesis of sinters exposed within the Los Geysers geothermal field, Trans-Mexican Volcanic Belt (TMVB) north-central sector. Petrographic observations, 14C ages, whole-rock geochemistry, and Sr isotopic analyses were undertaken to address the primary goal of this research. The siliceous sinters precipitated in Los Geysers were characterized by a lack of diagenetic maturation, being composed of non-crystalline opal-A, classified as “dry opal” (4.53–8.08 wt% of the H2O+). Petrographic observations revealed a high abundance of diatom frustules. Middle and distal apron lithofacies were associated with a relatively calm depositional pool environment (warm to mesothermal conditions). Sinter growth occurs mainly by evaporation of the geothermal water mobilized by capillary creep through the porous matrix. The earliest hydrothermal activity in the Los Geysers area is dated at ~6.7 kyr. B.P. The difference in deposition ages between two sinter mounds (~2.0 kyr) suggests a relationship between palaeo-seismic events (>6.9 Mw) and the hydrothermal activity. Chemically, the sinters were composed mainly of SiO2 (91.63–97.60 wt%) with minor amounts of CaO (0.17–0.98 wt%), Na2O (0.08–0.31 wt%), and MgO (0.06–0.11 wt%). Trace elements such as Cs, Co, Ga, B, Be, Sr, and Li are enriched because of their hydrothermal nature and presented similar contents relative to the Upper Continental Crust (UCC). Sr-isotopic values (0.706038–0.706955) and rare earth elements (REE) patterns normalized with the Post-Archean Australian Shale (PAAS) standard (LaN/SmN = 0.36–0.80; YbN/SmN = 0.26–0.67; Eu/Eu⁎ = 1.33–1.67) reflect the bulk composition of the precursor liquid.

A fault diagnosis method for underwater thruster based on RFR-SVM

A fault diagnosis method for underwater thruster based on Random Forest Regression (RFR) and Support Vector Machine (SVM) is proposed in this paper. Aiming at the problem of insufficient fault diagnosis accuracy caused by the extremely unbalanced scale of normal samples and fault samples, a data argumentation method of fault samples based on RFR is proposed. Considering the over-fitting phenomenon of machine learning in the case of small samples, tsfresh package, and kernel principal component analysis (KPCA) are used to extract features from thruster time series data, and then the SVM is used to train the thruster fault diagnosis model. Finally, the effectiveness of the proposed method is verified by experiment in a pool environment.

Swimming Pool Regulations in the COVID-19 Era: Assessing Acceptability and Compliance in Greek Hotels in Two Consecutive Summer Touristic Periods

The COVID-19 pandemic has urged many countries to issue new regulations to assure safety in pool environments. Greece enforced stricter requirements in 2020 and 2021 for hotel pools. However, even though regulations are important, they can only be effective when accepted by the pool managers and users. The aim of this study was to (a) assess the acceptability of the regulations by hotel managers; (b) assess compliance during the summer touristic periods in 2020 and 2021; and (c) identify challenges during the implementation of the regulations that need to be addressed. Several non-compliances from the regulations were identified. Continuous chlorination with an automatic chlorinator was not a regular practice and suggested water circulation rates were poorly met. The microbiological and chemical testing frequency of the pool water and keeping the number of bathers allowed per surface area in the pool were reported as the most difficult requirements to meet. Most pool managers agreed that new measures contribute to the pool users’ safety; however, they reported increased cost as the main impediment for their implementation. The modernization of regulations governing swimming pools’ function, in terms of risk assessment orientation, will contribute to the adoption of an integrated compliance strategy on emerging health issues, such as COVID-19.

Characterization of the wave phenomenon of flash-induced chlorophyll fluorescence in Chlamydomonas reinhardtii

Flash-induced chlorophyll fluorescence relaxation is a powerful tool to monitor the reoxidation reactions of the reduced primary quinone acceptor, QA− by QB and the plastoquinone (PQ) pool, as well as the charge recombination reactions between the donor and acceptor side components of Photosystem II (PSII). Under certain conditions, when the PQ pool is highly reduced (e.g. in microaerobic conditions), a wave phenomenon appears in the fluorescence relaxation kinetics, which reflects the transient reoxidation and re-reduction of QA− by various electron transfer processes, which in cyanobacteria is mediated by NAD(P)H dehydrogenase (NDH-1). The wave phenomenon was also observed and assigned to the operation of type 2 NAD(P)H dehydrogenase (NDH-2) in the green alga Chlamydomonas reinhardtii under hydrogen-producing conditions, which required a long incubation of algae under sulphur deprivation (Krishna et al. J Exp Bot 70 (21):6321–6336, 2019). However, the conditions that induce the wave remained largely uncharacterized so far in microalgae. In this work, we investigated the wave phenomenon in Chlamydomonas reinhardtii under conditions that lead to a decrease of PSII activity by applying hydroxylamine treatment, which impacts the donor side of PSII in combination with a strongly reducing environment of the PQ pool (microaerobic conditions). A similar wave phenomenon could be induced by photoinhibitory conditions (illumination with strong light in the presence of the protein synthesis inhibitor lincomycin). These results indicate that the fluorescence wave phenomenon is activated in green algae when the PSII activity decreases relative to Photosystem I (PS I) activity and the PQ pool is strongly reduced. Therefore, the fluorescence wave could be used as a sensitive indicator of altered intersystem electron transfer processes, e.g. under stress conditions.

Ability of Lifeguards to Detect Submerged Manikins in Public Swimming Pool Environments

To prevent drownings in public swimming pools (PSP), French legislation requires constant surveillance by state-certified lifeguards. While previous research showed that surveillance was not always effective, this article focuses on efficiency of surveillance when it is effective. We evaluated the ability of 4 volunteer professional lifeguards to detect a submerged manikin under controlled conditions. One hundred and eight (108) tests were carried out in 2 PSP. Four variables were controlled (i.e., distance, depth, surveillance station, attendance). Our results showed that rapid drowning detection was not exclusively linked to the individual detection capabilities of a lifeguard, but rather it emerged from a tight coupling between the lifeguard’s perception and his/her working environment. The tests performed in this study are useful to prevent drownings and therefore should be reproduced in other public swimming pools (i) to identify problematic situations and (ii) to train lifeguards’ surveillance capabilities.

What is the adequate number of students per class for safety in swimming lessons? Reflection by teachers from Rio de Janeiro, Brazil/ Qual o quantitativo adequado de alunos por turma para segurança na aula de natação? Reflexão de professores do Rio de Janeiro, Brasil

Drowning is a global problem that shouldn't affect anyone. Learning to swim can be an ally in preventing drowning, however, the place where classes take place also requires attention so that students are safely exposed to the pool. The objective of this study is to reflect on the appropriate number of students per class, in swimming lessons so that there is a safe + class. The methodology used was cross-sectional, multi-method research, carried out in two stages, the first (n 107), interviewing swimming teachers from academies in the State of Rio de Janeiro; the second (n 44) was carried out online, with a self-answered questionnaire by swimming teachers who are part of the pool + safe group. Qualitative data analysis was performed through content analysis. The results show that there are at least 10 variables that influence teachers in deciding how many students each class can have. These ten items were grouped into three groups of responses that are subdivided into: 1. Students (stature, aquacity and medical clearance); 2. Teachers (assistant in the water, prevention course in the aquatic area and experience); and 3. pool environment (depth reducer, handrail on the edge, life guard and teaching material). The professionals involved in deciding how many students, per class, should put in the pool, at each time, need to evaluate each variable to later be able to combine quality, safety and quantity in each swimming class. In this sense, student safety needs to be the protagonist in this scenario, so that no incident occurs during swimming lessons. It is suggested that the teacher constantly reassess their aquatic environment to verify if these factors, which are not included in the test of how many students each class can have, are preventing their class from having a safe + class.

Subjective and Objective Quality Assessment of Swimming Pool Images.

As the research basis of image processing and computer vision research, image quality evaluation (IQA) has been widely used in different visual task fields. As far as we know, limited efforts have been made to date to gather swimming pool image databases and benchmark reliable objective quality models, so far. To filled this gap, in this paper we reported a new database of underwater swimming pool images for the first time, which is composed of 1500 images and associated subjective ratings recorded by 16 inexperienced observers. In addition, we proposed a main target area extraction and multi-feature fusion image quality assessment (MM-IQA) for a swimming pool environment, which performs pixel-level fusion for multiple features of the image on the premise of highlighting important detection objects. Meanwhile, a variety of well-established full-reference (FR) quality evaluation methods and partial no-reference (NR) quality evaluation algorithms are selected to verify the database we created. Extensive experimental results show that the proposed algorithm is superior to the most advanced image quality models in performance evaluation and the outcomes of subjective and objective quality assessment of most methods involved in the comparison have good correlation and consistency, which further indicating indicates that the establishment of a large-scale pool image quality assessment database is of wide applicability and importance.

Experimental study of oil pool shape and environment pressure on the wall fire behavior in an airplane cargo compartment

A series of pool fires were carried out to study the effect of pool shape and environment pressure on the wall fire behavior. Four sizes of annular pool and three sizes of rectangle pool were used as the oil container. The results showed that the burning rate of both the annular and rectangle pool fire increased with increasing length ratio of the poolside, which was defined as the ratio of the inside and outside diameter for the annular pool (η) and aspect ratio (n) for rectangle pool. At the stable burning stage, the pool burning rate increased with the environmental pressure. While the flame height was not a monotonous trend with the pressure for rectangle pool fire, and the flame height in two kinds of pools exhibited opposite tendencies as the length ratio was increased. In addition, by introducing the shape parameter of the pool into the classical model, correlations to calculate the mass burning rate and the height of the pool fire flame under the limited sidewall conditions at different pressure environments were established.

Experimental research on influence of wave environment on high-speed water entry load and trajectory characteristics

Wave environment is a common fact happened when objects enter water under real conditions, which changes the morphology of the free interface when entering water. However, the influence of wave environment on the flow when entering water and on the evolution of object motion parameters after entering water is not clear. In this research, a rocking plate wave maker is used to generate a wave environment in the test pool, and a truncated cone rotating body equipped with an internal test system is used as the test model. The compressed air cannon is used to provide launch power, and the launch control system uniformly controls the start timing process of the wave maker and the launcher. The wave maker and the launcher will control the relative position of the object's entry point and the wave surface in collaboration. Various condition tests were carried out, including enter in static water, different wave surface positions and different wave heights. Quantitative trajectory parameters including the acceleration, and attitude angle of the model in the water-entry process were obtained, and the evolution of the flow field was photographed. The experimental results show that under high-speed conditions, the influence of waves on the water-entry process is mainly reflected in the change of the water entry angle relative to the water surface at the water-entry moment. The wave surface encountering negative inclination can effectively reduce the impact load of water entry, but it is more likely to induce the extreme situation such as "jumping".

Construction Method of Swimming Pool Intelligent Assisted Drowning Detection Model Based on Computer Feature Pyramid Networks

Swimming pool intelligent assisted drowning detection is an important research content in the field of drowning rescue. A large number of scholars track drowning targets in real time through underwater intelligent monitoring system, and use it to build a reliable swimming pool intelligent assisted drowning detection model to reduce the risk of drowning. For the complex underwater environment of the swimming pool, the previous detection model has been difficult to adapt to the practical demand. In this regard, based on the summary of the previous swimming pool intelligent assisted drowning detection models and the computer feature pyramid networks, the feature stratification of the swimming pool intelligent assisted drowning detection image is completed, and then the final swimming pool intelligent assisted drowning detection results are obtained through the YOLO principle. After analysis, it is confirmed that the accuracy rate of swimming pool intelligent assisted drowning detection of this method is significantly improved, which can provide effective data theoretical guidance for swimming pool intelligent assisted drowning rescue and has significant practical advantages.

Adverse outcomes in people with swimming pool associated diabetic foot infection: a case series

AbstractExercise through swimming is beneficial for patients with diabetes; however, swimming pool environments are known to favour infection. There is at present no available literature on outcomes of swimming pool associated diabetic foot infections and we describe a novel case series of patients who presented with foot infections after using a swimming pool.Individuals attending our Diabetes Limb Salvage Clinic with foot ulcers/infections who had an injury or infection after exposure to a swimming pool environment were identified. We noted ulcer characteristics, pathogens, length of hospital stay and clinical outcomes.Seven individuals (six male, one female, aged 36–68 years) were exposed to a swimming pool environment while on holiday, and within 48 hours had a new ulcer or worsening of their pre‐existing ulcers. Five had new ulcers (two injured their feet on the swimming pool floor, three developed blisters after swimming); two had worsening of their pre‐existing foot ulcers. All patients required hospitalisation (5–20 days) at presentation with severe foot infection. Microbiology showed six patients had mixed flora isolated from their ulcers: Staphylococcus aureus (three), Corynebacterium (two), enteric flora (two), Pseudomonas (one), Streptococcus group C‐G (one) and Bacteroides (one). In terms of outcomes: one patient had a below knee amputation; two required minor amputations.People with diabetes who sustain a foot injury in a swimming pool environment may develop complex infections with waterborne organisms that can be difficult to eradicate, resulting in considerable morbidity including amputation. These risks need to be highlighted and individuals with diabetes advised to protect their feet in water. Copyright © 2021 John Wiley & Sons.

Knowledge, Attitude and Practices Towards Cryptosporidium Among Public Swimming Pool Patrons and Staff in Western Australia.

There is a dearth of research conducted on the Knowledge, Attitude and Practices (KAP) of swimming pool patrons and staff to determine their understanding of the importance of Cryptosporidium and its transmission in swimming pools. We conducted a KAP survey of public swimming pool patrons (n = 380) and staff (n = 40) attending five public swimming pools in Western Australia (WA). Knowledge, attitudes and practices (KAP) of Cryptosporidium varied between patrons and staff but were generally limited. Only 26.1% and 25.0% of patrons and staff had heard of Cryptosporidium, while 17.4% and 10.0% knew that it causes diarrhoea, respectively. Thirty-one percent of patrons were aware of their pool policy concerning gastroenteritis and Cryptosporidium, compared to 62.5% of staff. Less than 50% of patrons demonstrated awareness of how features within the pool environment were relevant to the control of Cryptosporidium. Only about a third of patrons (35%) and staff (37.5%) were aware that showering before swimming reduced the risk of gastroenteritis. Raising awareness about hygiene-related practices through the delivery of targeted health education messages to the general public is essential to reduce the burden of Cryptosporidium infections in aquatic environments.

Tinjauan Sanitasi Kolam Renang Tirta Srinadi Klungkung Tahun 2021

Ida Ayu Putri Windari1, Nyoman Purna2 Abstract : Tirta Srinadi swimming pool opened on April 13th 2012, located at Banjar Minggir, Gelgel, Klungkung Regency and it has two swimming pools. Preliminary observations showed the swimming pools for toddlers and children, there are floating objects on the water, smell of chlorine scent is too stinging, the floor around the pool is slippery, poorly maintained, no urinal and hand washing in the swimming pool area. This research is conducted to find out the swimming pool sanitation condition which includes the water quality, sanitation facility, and construction of the building. The result is divided into two categories; sanitary condition does not qualify if the score is 0-30,5 and 30,6-61 is qualified. The results showed that Tirta Srinadi Swimming Pool fulfilled the requirements because from 61 items examined; 48 points "Yes" and 13 points "No". The recommendation to management is keep maintaining the cleanliness swimming pool environment and chemicals dosage need to be adjusted to the water volume of the swimming pool to avoid inconvenience on the visitors.

An empirical confirmation of diversified bet hedging as a survival strategy in unpredictably varying environments.

Environmental change jeopardizes the survival of species from variable environments by making the occurrence of favorable conditions less predictable. For organisms with long-lived propagules (e.g., spores, eggs, or seeds), the theory of diversified bet hedging (DBH) predicts that delayed hatching over different growing seasons can help populations avoid extinction. Empirical observations in different organisms are consistent with DBH, but integrated tests that simultaneously validate the main theoretical assumptions and predictions are lacking. In this study, we combine field and multi-generational lab experiments to provide a complete test of DBH. Consistent with DBH predictions, resting egg clutches of the fairy shrimp Branchipodopsis wolfi, which inhabits rain-fed temporary rock pool environments with unpredictable inundations, hatched partially over a succession of inundations with identical hatching cues. Bet hedging was more common in populations from more unpredictable habitats where hatching fractions were lower. This differentiation in hatching strategies was preserved after two generations under common garden conditions, which implies intrinsic (epi-)genetic control of hatching. Finally, a demographic model confirmed that lower hatching fractions increase long-term population growth in unpredictable habitats. With this paper we propose a method to calculate probabilities of successful recruitment for organisms that use imperfect cues and show that this drives selection for variation in life history strategies as part of a DBH strategy.

Determination of chloroform concentration and human exposure assessment in the swimming pool

This cross-sectional study aimed to examine the concentration of the by-products of chlorination in the swimming pool and estimate human health risk for the swimmers of Shiraz University of Medical Sciences. In this study, the chloroform concentrations of 16 samples were measured using Gas Chromatography (GC). All the measured concentrations were less than the allowed amount announced by the World Health Organization (WHO). The results of the cancer risk (CR) and hazard index (HI) showed that the major exposure routes were found to be dermal during swimming and the 95 percentile of estimated CR and HI for the male group were 1.38 × 10−10 and 1.82 × 10−5 respectively, which is higher than the values of 5.48 × 10−10 and 2.25 × 10−5 respectively, for the women group. Sensitivity analyses indicated that the swimming exposure time (ET), and chloroform concentration were the most relevant variables in the health risk model. Therefore, knowledge about the sources of micro-pollutants in swimming pools might help promote the health methods of the pool environment.

Search for a distressed swimmer in a dynamic, real-world environment.

Visual search is increasingly being explored in dynamic, real-world environments. This includes swimming pools, where lifeguards have shown superior drowning detection in simulated environments. Here, we explored if lifeguard superiority is observed in real-life scenes of a busy swimming pool. Experiment 1 required participants to identify real-life distressed swimmers in clips of busy pool activity via a touchscreen interface. Experiment 2 sought to replicate the first study, with the inclusion of eye-movement measures. Experiment 3 varied the methodology, using an occlusion method where clips were frozen and blurred shortly after target onset. The results demonstrated an experience effect, with lifeguards detecting distressed swimmers more often and faster than nonlifeguards. No clear differences were found in the eye-movements between groups; thus, we cannot conclude that the lifeguards' faster responses are due to better scanning strategies. The different methodological approaches revealed the occlusion method to have the larger effect size, supporting the growing evidence that occlusion may be a better test for dynamic target detection than traditional response-time tests. This research demonstrates that the clear lifeguard experience effect generalizes to real-life pool environments with a large number of swimmers and real incidents. It could be used to inform lifeguard training tools and assessments. (PsycInfo Database Record (c) 2021 APA, all rights reserved).