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The work reports an analysis of vital signs of human beings through a smart heart beat and pulse monitoring system based on Arduino device. Vital signs include heart rate, pulse monitoring and oxygen level of a human being. The system contribute improvements in individual’s healthcare out-comes. AD8232 ECG sensor is used through Arduino Mega which amplify and filters the ECG signals obtained from the electrodes. Arduino Mega is powered by 5 V supply voltage. ECG sensor uses 3 cables which has disposable patches and connected to the chest of human being to capture bioelectric signals. Hence, heart rate and pulse of a human being has been monitored. An additional capacitive filter circuit is used Furthermore, MAX30102 sensor have been used to determine the oxygen level of a person. The results obtained from the study provides a good accuracy. The heart rate varies as per the age of human being. The oxygen accuracy level falls in the range of 95% to 100%. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the risk of severe heat stress and associated potential water losses in professional soccer players, considering as well the oxygen content of the inhaled air in the context of the 2026 FIFA World Cup. For the 16 stadiums, hourly values of biometeorological indices (adjusted Universal Thermal Climate Index – UTCI, Water loss – SW and Oxygen volume - Ov) were calculated. UTCI adjustments included modifications to activity levels, movement speeds and clothing configurations to better reflect the level of thermal stress on soccer player during a match. Ten out of the sixteen sites of the 2026 FIFA World Cup are at very high risk of experiencing extreme heat stress conditions. The highest risk of uncompensable thermal stress due to very high average hourly UTCI values above 49.5 °C and excessive water loss (> 1.5 kg/h) occur in the afternoon in stadiums located in Arlington, Houston (USA) and in Monterrey (Mexico). The results of this study will enable optimization of match schedules at individual venues, taking into account the health risks associated with extreme heat stress, but also the physiological reactions to heat potentially affecting the performance of players on the pitch.

Background: Although there are some studies trying to detect various long or post coronavirus disease (COVID-19) symptoms and some risk factors, long COVID-19 symptoms and their association with some possible risk factors such as age, sex, blood group, and oxygen level are still not well understood and required more studies worldwide. Objective: Therefore, this study included 206 patients. My questionary has different questions for the participants such as the type of symptoms they had post COVID-19 infection, to determine the most prevalence long symptoms. Materials and Methods: Moreover, to determine the association of post-acute sequelae of COVID-19 with some risk factors, the questionnaire included questions about the participant's age, gender, blood group, and oxygen rate during the infection. Results: My results showed that fatigue and muscle pain are the most prevalent long or post COVID-19 symptoms followed by forgetfulness and depression, chest pain and cough, loss of smell and taste, diarrhea, and abdominal pain. Also the results found that female patents, and persons with age from 19 to 29, as well as positive Rh blood group except AB+ are more susceptible to long symptoms. Moreover, the results showed that there is an association between oxygen rate reduction and the long COVID-19 symptoms. Conclusion: Some corona virus patients develop post disease symptoms, and it looks like that variable factors influence that. So understanding the correlation between appearance of the long COVID-symptoms and these the risk factors presents valuable insights, the conclusions warrant justification through larger clinical trials. [ABSTRACT FROM AUTHOR]

The combined effects of breeder age and oxygen (O2) concentrations on embryo development, hatching events, chick quality, embryonic mortality and hatchability were investigated. A total of 900 hatching eggs of average weight of 53.85 ± 2.40 g and 60.42 ± 2.02 g from 33 to 50 wks ISA layer breeders were incubated for six days at 37.7 °C temperature and 56 % relative humidity (RH) before exposure to hypoxic stimulation of 15 % and 17 % O2 (experimental groups) and 21 % O2 (control group). In a 2 x 3 factorial experiment, air-N2 flushing to reduce O2 was 1 h daily from embryonic day (ED)7–9. The study investigated fresh egg weight before setting, egg weight loss and embryonic parameters at ED11, hatching events, chick quality, embryonic mortality and hatchability. Results showed that regardless of breeder age, early mild hypoxia reduces (P

This article aims to predict vital signs like heart rate (HR), respiration rate, and arterial oxygen saturation using ambient light video, eliminating chronic distortions through improved frame quality with BER estimation. The study employs the cascade residual CNN‐FPNR technique for preprocessing and SNR enhancement using energy variance maximization. The image cascade network (ICNet) facilitates segmentation, achieving strong segmentation in low‐light ambient videos. Remote photoplethysmography (iPPG) enables noncontact vital sign monitoring, predicting HR and respiratory rate (RR). An innovative noninvasive temperature and cyclical algorithm, incorporating principal component analysis and fast Fourier transform, evaluate patient HR and RR. To address challenges related to involuntary movements, a dynamic time‐warping‐based optimization method is used for precise region selection. The study introduces an intensity variance‐based threshold analysis for arterial oxygen saturation level determination. Ultimately, the support vector machine (SVM) classification technique evaluates the ground truth, showcasing the system's promising potential for remote and accurate vital sign assessment. [ABSTRACT FROM AUTHOR]

Background/Purpose: Due to the general application of in vitro test, cell culture is generally selected to evaluate the cytocompatibility of devices and materials. The choice of test condition should depend on the probable site and clinical application. The oxygen content of human body could be estimated around 5%∼12%, and the oxygen level of healing bone fracture range from 0.8%∼3.8%%. However, materials for bone implant are traditionally evaluated under laboratory normoxia condition (21% O2) in vitro. The aim was to study the effect of oxygen level on osteoblast upon high stiffness titanium with different roughness. Methods: After sandblasted and acid-etched (SLA) process, we create titanium surfaces with four different roughness. The differentiation and proliferation of MC3T3-E1 osteoblast cultured on SLA-treated specimens were evaluated in designed chamber with oxygen level of 1%, 5%, 10%, 21%. Results: By scanning electron microscopy, all samples had sub-micro pit inside the micro-holes upon SLA-treated Ti disk surface. The decrease of oxygen level from 21% to 5% promoted osteoblast growth of SLA-treated specimens, but 1% O2 delayed cell proliferation. The surface roughness of specimens influenced osteoblast cell differentiation. The differentiation and proliferation ability of the cells upon SLA-treated specimens is proportional to oxygen level. Conclusion: Our results demonstrated that 5% O2 will easily discriminate osteoblasts responses on different SLA-treated specimens. These results suggest that hypoxia (5% O2) environment is better model for biological evaluation of bone-related materials.

Recently, COVID-19 becomes a hot topic and explicitly made people follow social distancing and quarantine practices all over the world. Meanwhile, it is arduous to visit medical professionals intermittently by the patients for fear of spreading the disease. This IoT-based healthcare monitoring system is utilized by many professionals, can be accessed remotely, and provides treatment accordingly. In context with this, we designed an IoT-based healthcare monitoring system that sophisticatedly measures and monitors the parameters of patients such as oxygen level, blood pressure, temperature, and heart rate. This system can be widely used in rural areas that are linked to the nearest city hospitals to monitor the patients. The collected data from the monitoring system are stored in the cloud-based data storage and for the classification our approach proposes an innovative Recurrent Convolutional Neural Network (RCNN) based Puzzle optimization algorithm (PO). Based on the outcome further treatments are made with the assistance of physicians. Experimental analyses are made and analyzed the performance with state-of-art works. The availability of more data storage capacity in the cloud can make physicians access the previous data effortlessly.

Due to the general application of in vitro test, cell culture is generally selected to evaluate the cytocompatibility of devices and materials. The choice of test condition should depend on the probable site and clinical application. The oxygen content of human body could be estimated around 5%∼12%, and the oxygen level of healing bone fracture range from 0.8%∼3.8%%. However, materials for bone implant are traditionally evaluated under laboratory normoxia condition (21% O 2) in vitro. The aim was to study the effect of oxygen level on osteoblast upon high stiffness titanium with different roughness. After sandblasted and acid-etched (SLA) process, we create titanium surfaces with four different roughness. The differentiation and proliferation of MC3T3-E1 osteoblast cultured on SLA-treated specimens were evaluated in designed chamber with oxygen level of 1%, 5%, 10%, 21%. By scanning electron microscopy, all samples had sub-micro pit inside the micro-holes upon SLA-treated Ti disk surface. The decrease of oxygen level from 21% to 5% promoted osteoblast growth of SLA-treated specimens, but 1% O 2 delayed cell proliferation. The surface roughness of specimens influenced osteoblast cell differentiation. The differentiation and proliferation ability of the cells upon SLA-treated specimens is proportional to oxygen level. Our results demonstrated that 5% O 2 will easily discriminate osteoblasts responses on different SLA-treated specimens. These results suggest that hypoxia (5% O 2) environment is better model for biological evaluation of bone-related materials. [ABSTRACT FROM AUTHOR]

Aims: Among solid tumors, hypoxia is a common characteristic and responsible for chemotherapeutic resistance. Hypoxia-sensitive imaging probes are therefore essential for early tumor detection, growth monitoring and drug-response evaluation. Despite significant efforts, detecting hypoxic oxygen levels remains challenging. Materials & methods: This paper demonstrates the use of an amine-rich carbon dot probe functionalized with an imidazole group that exhibits reversible fluorescence switching in normoxic and hypoxic environments. Results & conclusion: We demonstrate the ability to emit near-infrared light only under hypoxic conditions. The probes are found to be biodegradable in the presence of human digestive enzymes such as lipase. Ex vivo tissue imaging experiments revealed promising near-infrared signals even at a depth of 5 mm for the probe under ex vivo imaging conditions. Hypoxia is the state where oxygen is not adequately available at the tissue level and is the common cause of resistance toward chemotherapeutics. Hence, probes that can detect hypoxia are important in detecting early tumor progression. Here in this paper, we have developed a fluorescent probe which helps in determining normoxic and hypoxic environments. This probe emits near-infrared light only under hypoxic conditions. The phenomena have been established herein by extensive experiments. [ABSTRACT FROM AUTHOR]

The Indonesian shortfin eel (Anguilla bicolor bicolor McClelland, 1884) is catadromous fish. The developmental phase of the fish is influenced by the availability and type of feed, and dissolved oxygen levels (DO). Oxygen level fluctuations during migration from sea to fresh waters can cause hypoxia and trigger activation of the Hypoxia-inducible factor 1 alpha gene (HIF-1α). Therefore, undertanding HIF-1α expression is very important in understanding the life cycle and physiology of this organism. This study aimed to perform a histological comparison between the liver structure of eel in the elver eel phase to silver eel and compared the expression of HIF-1α in the liver. The eels were collected from Kulon Progo Regency, Segara Anakan in Cilacap, and Cangkringan in Sleman, respectively. The eel livers were prepared with standard paraffin method. The samples were stained with Hematoxylin-Eosin, Mallory Acid Fuchsin and Periodic Acid-Schiff Alcian Blue for histological observation. The HIF-1α protein expression was detected using immunohistochemistry. The results showed that the structure of liver elver, yellow, and silver eel shared similar tubular hepatocytes. Moreover, there was no significant differences in the parenchymal structure of liver of all stage of eel. Mucin levels were different in each life cycle phase. HIF-1α expression varied by eel phase, with the elver eel showing weak expression, yellow stage showing moderate expression, and silver eels displaying the highest levels of expression. We conclude that the highest expression of HIF-1α was found in the silver eel, which resides in freshwater environments and is found in freshwater while returning to the sea for reproduction. [ABSTRACT FROM AUTHOR]

The intensity of climatic changes and human activities is increasing every year. The general consequence of these processes for freshwater ecosystems can be a dissolved oxygen decrease. There is also a possibility of a reduction in geomagnetic field intensity due to a reversal of the Earth's magnetic poles. It is assumed that the magnetic poles' reversal may proceed relatively quickly and coincide with global climatic changes. To evaluate the influence of these processes on aquatic organisms, we studied the effects of different dissolved oxygen levels (2 mg/L, 5 mg/L, and 8 mg/L) under the geomagnetic field (51.7 ± 0.2 μT) and hypomagnetic field (0 ± 0.2 μT) on the model freshwater crustacean Daphnia magna Straus. It was found that reduced oxygen levels and the hypomagnetic field led to a decrease in the sizes of parental females, a reduction in the number of produced offspring, and an increase in the period between broods. The newborns from the first brood in the hypomagnetic field were larger than that from the geomagnetic field. The dissolved oxygen level and magnetic environment affected the age of the first brood release and caudal spine length. The results imply that the probable coincidence of the geomagnetic pole reversal and the decrease in the dissolved oxygen level due to global climatic and geophysical processes will have a more negative impact on freshwater crustaceans than the occurrence of these processes at different times. [ABSTRACT FROM AUTHOR]

IoT (Internet of Things) is a revolutionary technology which establishes an interconnected network for everything. With an IoT being a burgeoning industry for the future, significantly in the field of health care, wearable gadgets can be manufactured, which enables IoT to connect with individual’s health track or history in a smart way, especially with recent advancements in wireless sensor networks. Thus, a doctor can keep an eye on a patient’s health. The major focus of this paper is to build a module which measures basic parameters required with multiple use of sensors and integration of the monitoring system with an IoT. [ABSTRACT FROM AUTHOR]

Tent shielding is an effective and flexible method to provide inert protective atmosphere during wire arc additive manufacturing of titanium alloy. In this study, five deposited walls were fabricated by CMT-WAAM process with different oxygen levels in the tent shielding, and the influences of oxygen levels on the microstructure and mechanical properties were analyzed. The results showed that, the oscillated path provided enough time for the molten pool to absorb oxygen out of atmosphere. With the increase in oxygen level, the thickness of α-case with higher micro-hardness became larger, the amount of β phase gradually decreased, the ratio of length to width for α lamellar was increased, and the boundary α phase became coarser. The higher oxygen level in the tent shielding caused an increase in tensile strength and a decrease in elongation. An ultimate tensile strength higher than 900 MPa and an elongation higher than 6% could be obtained when the oxygen level in the tent was lower than 2000 ppm. [ABSTRACT FROM AUTHOR]

Today, the general situation worldwide is that the hospitals, sanatoriums and medical colleges are running out of beds, oxygen, medical staff, ventilators and other required paraphernalia that is mandatory for the treatment of the vicious pandemic [1]. The requirement is for a system that takes in some input parameters like Oxygen level of the patient, pulse rate and respiration rate and in turn predicts the Life Risk Rate of that patient [2]. The model used here is a fuzzy regression model that gives the prediction of Life Risk Rate between 1 and 10 units. The lower the predicted Life Risk Rate, the better the chances of survival of the Covid patient. But if the predicted Life Risk Rate is more than the mean of the observations of the Risk in the dataset, then immediate emergency is needed. The benefit of this system is that the patients requiring immediate admission and treatment can be filtered and medical aid in hospital be thereby provided for critical patients. Rest may be home quarantined and domestic medical aid may be given to them until in some unfortunate situation their Risk Rate is near alarming. This paper aims to provide some help in this crucial situation. [ABSTRACT FROM AUTHOR]

Background: Obstructive sleep apnea (OSA) is a condition causing restriction of the airflow through the upper airways during sleep, despite preserved inspiratory muscle activity. This may lead to the development of secondary hypertension, ischemic heart disease, myocardial infarction, and arrhythmia. Moreover, the prevalence of OSA is on the rise. Methods: Comparison of scores from the Berlin Questionnaire, modified Mallampati scores (MMP), pulse oximetry readings and Upper Airway Volume (UAV) data obtained from CBCT (Cone Beam Computed Tomography). The study group of 129 patients of both sexes reporting sleep-related breathing problems completed the Berlin Questionnaire, had their oxygen saturation (SpO2) measured with a PO40 pulse oximeter, and oropharyngeal tissues assessed according to MMP. CBCT scans were put into 3D Amira TM 3D computer analysisto obtain UAV values. Results: Snoring was associated with significantly higher BMI compared to non-snoring patients. Furthermore, snoring patients had higher heart rate, modified Mallampati score, and lower UAV than the non-snoring group. The multifactorial analysis showed MMP as a useful indicator of the risk of snoring (OR = 7.468 (3863–14, 507, p < 0.001)). Conclusions: The composition of MMP together with UAV and the Berlin questionnaire might be reliable indicators to assess the risk of snoring. [ABSTRACT FROM AUTHOR]

Abstract: The mechanisms underlying headaches attributed to hypoxia are poorly known. The activation of spinal trigeminal neurons with meningeal afferent input is believed to be responsible for the generation of headaches. In the caudal spinal trigeminal nucleus of anaesthetized and ventilated rats, the spontaneous firing of neurons with input from the exposed parietal dura mater and the activity evoked by mechanical stimuli to the dura and the adjacent periosteum were recorded, whereas the O2 fraction of the ventilation gas was stepwise reduced by omitting O2 and adding nitrogen. The expiratory CO2 level, the arterial pressure, the pulse rate, and the peripheral O2 saturation (SpO2) were registered. The meningeal blood flow was recorded using laser Doppler flowmetry; video imaging was used to measure the diameter of dural and medullary arteries. Lowering O2 in the ventilation gas from hyperoxic to normoxic and finally hypoxic conditions was followed by an increase in spontaneous activity up to 300% of the initial activity in most neurons, whereas the activity in a minor fraction of neurons ceased. The mechanical threshold was reduced under hypoxia. Arterial pressure, pulse rate, and SpO2 fell during stepwise lowering of the O2 concentration, whereas the arteries of the dura mater and the medulla dilated. Increased neuronal activity in the spinal trigeminal nucleus following lowering of the inhaled O2 goes along with variations in cardiovascular parameters. The experiments may partly model the conditions of high altitudes and other hypoxic states as risk factors for headache generation. [ABSTRACT FROM AUTHOR]

Copyright of Investigación e Innovación en Ingenierías is the property of Universidad Simon Bolivar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Investigación e Innovación en Ingenierías is the property of Universidad Simon Bolivar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Pulse oximeters work within the red-infrared wavelengths. Therefore, these oximeters produce erratic results in dark-skinned subjects and in subjects with cold extremities. Pulse oximetry is routinely performed in patients with fever; however, an elevation in body temperature decreases the affinity of hemoglobin for oxygen, causing a drop in oxygen saturation or oxyhemoglobin concentrations., Objective: We aimed to determine whether our new investigational device, the Shani device or SH1 (US Patent 11191460), detects a drop in oxygen saturation or a decrease in oxyhemoglobin concentrations., Methods: An observational study (phase 1) was performed in two separate groups to validate measurements of hemoglobin and oxygen concentrations, including 39 participants recruited among current university students and staff aged 20-40 years. All volunteers completed baseline readings using the SH1 device and the commercially available Food and Drug Administration-approved pulse oximeter Masimo. SH1 uses two light-emitting diodes in which the emitted wavelengths match with absorption peaks of oxyhemoglobin (hemoglobin combined with oxygen) and deoxyhemoglobin (hemoglobin without oxygen or reduced hemoglobin). Total hemoglobin was calculated as the sum of oxyhemoglobin and deoxyhemoglobin. Subsequently, 16 subjects completed the "heat jacket study" and the others completed the "blood donation study." Masimo was consistently used on the finger for comparison. The melanin level was accounted for using the von Luschan skin color scale (VLS) and a specifically designed algorithm. We here focus on the results of the heat jacket study, in which the subject wore a double-layered heated jacket and pair of trousers including a network of polythene tubules along with an inlet and outlet. Warm water was circulated to increase the body temperature by 0.5-0.8 °C above the baseline body temperature. We expected a slight drop in oxyhemoglobin concentrations in the heating phase at the tissue level., Results: The mean age of the participants was 24.1 (SD 0.8) years. The skin tone varied from 12 to 36 on the VLS, representing a uniform distribution with one-third of the participants having fair skin, brown skin, and dark skin, respectively. Using a specific algorithm and software, the reflection ratio for oxyhemoglobin was displayed on the screen of the device along with direct hemoglobin values. The SH1 device picked up more minor changes in oxyhemoglobin levels after a change in body temperature compared to the pulse oximeter, with a maximum drop in oxyhemoglobin concentration detected of 6.5% and 2.54%, respectively., Conclusions: Our new investigational device SH1 measures oxygen saturation at the tissue level by reflectance spectroscopy using green wavelengths. This device fared well regardless of skin color. This device can thus eliminate racial disparity in these key biomarker assessments. Moreover, since the light is shone on the wrist, SH1 can be readily miniaturized into a wearable device., (©Sanjay Gokhale, Vinoop Daggubati, Georgios Alexandrakis. Originally published in JMIR Biomedical Engineering (http://biomsedeng.jmir.org), 27.03.2024.)

Colorectal cancer is a common cancer with metachronous distant metastases still threatening overall survival. Tumor oxygen level influences tumor radiosensitivity in relation to autophagy and apoptosis. The objective of this study is to evaluate the expression and interaction between multiple key regulators in different oxygen levels. Human colorectal adenocarcinoma HT-29 cells were cultured in 1% or 10% oxygen level and irradiated by 2 Gy with different incubation time. Autophagy key regulators, AMPK, HIFs and JNK were evaluated by Western blot. Sequential autophagy key regulator activation was observed in the order of AMPK, HIF-1α, HIF-2α and JNK. 10% oxygen level could promote autophagy with similar degree of autophagy activation as 1% oxygen level in 48-h while irradiation could slightly inhibit autophagy. The results of this study supported prior evaluation of oxygen level and autophagy regulators for improving treatment efficacy and indicated the possible directions in developing individualized radiotherapy by selective targeting of hypoxic regions. • 10% O 2 level can promote autophagy with similar degree as 1% O 2 level in 48-h. • Sequential autophagy activation in the order of AMPK, HIF-1α, HIF-2α and JNK. • JNK for delayed autophagy activation as a novel key finding in low oxygen levels. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSCs) are a population of adult stem cells that modulate functional state of neighboring tissues. During cell aging, the biological activity of MSC changes, which may affect tissue homeostasis. It is known that reducing the oxygen level in vitro to physiological values typical to a particular cell niche leads to attenuation of some morphological and functional changes associated with aging. This work aimed to study gene expression in MSCs involved in response to physiological hypoxia using a replicative aging model under physiological (5%) and atmospheric (20%) oxygen in cultures. Our results show that significant reduction of proliferative activity of MSCs is observed after 20 passages (~50 cell generations). Regardless of the oxygen, in senescent cells PKM2, SERPINE1, and VEGFA were upregulated while ANKRD37, DDIT4, HIF1A, and TXNIP were downregulated. Also, ADORA2B, BNIPL, CCNG2, EGLN1, MAP3K1, MXI1, and P4HA1 were downregulated under hypoxia. The effect of oxygen was more pronounced at earlier passages both on the cellular and transcription levels. Irrespective of the passage, genes ANGPTL4, GYS1, PKM2, SERPINE1, and TP53 were downregulated under hypoxia. Also, decreased expression was observed for ADM, F10, HMOX1, P4HB, PFKL, SLC16A3 in earlier passages, and for HK2 – in later passages. Upregulation was only observed for ANKRD37, both at early and late cultures. [ABSTRACT FROM AUTHOR]

Background: Obstructive sleep apnea (OSA) is a condition causing restriction of the airflow through the upper airways during sleep, despite preserved inspiratory muscle activity. This may lead to the development of secondary hypertension, ischemic heart disease, myocardial infarction, and arrhythmia. Moreover, the prevalence of OSA is on the rise. Methods: Comparison of scores from the Berlin Questionnaire, modified Mallampati scores (MMP), pulse oximetry readings and Upper Airway Volume (UAV) data obtained from CBCT (Cone Beam Computed Tomography). The study group of 129 patients of both sexes reporting sleep-related breathing problems completed the Berlin Questionnaire, had their oxygen saturation (SpO2) measured with a PO40 pulse oximeter, and oropharyngeal tissues assessed according to MMP. CBCT scans were put into 3D Amira TM 3D computer analysisto obtain UAV values. Results: Snoring was associated with significantly higher BMI compared to non-snoring patients. Furthermore, snoring patients had higher heart rate, modified Mallampati score, and lower UAV than the non-snoring group. The multifactorial analysis showed MMP as a useful indicator of the risk of snoring (OR = 7.468 (3863–14, 507, p < 0.001)). Conclusions: The composition of MMP together with UAV and the Berlin questionnaire might be reliable indicators to assess the risk of snoring.

Background: In 2006, three farmers died at the bottom of an agricultural shallow well where the atmosphere contained only 6% oxygen. This study aimed to document the variability of levels of oxygen and selected hazardous gases in the atmosphere of wells, and to identify ambient conditions associated with the low-oxygen situation. Methods: A cross-sectional survey, conducted in June 2007 and July 2007, measured the levels of oxygen, carbon monoxide, hydrogen sulfide, and explosive gas (percentage of lower explosive limit) at different depths of the atmosphere inside 253 wells in Kamphaengphet and Phitsanulok provinces. Ambient conditions and well use by farmers were recorded. Carbon dioxide was measured in a subset of wells. Variables independently associated with low-oxygen condition (2 days vs. 25,000 ppm) in seven wells with a low oxygen level. Conclusion: Oxygen concentrations in the wells vary widely even within a small area and decrease with increasing depth.

Background: Myofascial Reorganization (MFR) is a physiotherapy technique that mixes myofascial pressures and slips and has been used as a simple and non-invasive method that readjusts soft tissues, as well as myofascial adhesions and contractures that may cause decreased blood supply and consequently of physical activity. Objective: To verify if the MFR alters the tissue oxygenation of the trapezius muscle (TM) in subjects without the pain symptom in the evaluation day. Methods: The sample consisted of eight subjects with a mean age of 23 (± 6) years and a body mass index of 23.2 (±15.0) kg.m-2. Changes in muscle oxygenation were measured by near infrared spectroscopy (NIRS) (Portamon, Artinis, the Netherlands) in TM before and after 15 minutes of intervention. The proposed MFR protocol lasted approximately 10 minutes and consisted of pressures, stretching and myofascial slippage of the upper, middle and lower TM fibers. Data normality was performed using the Shapiro Wilk test and due to the parametric nature of the data, the paired t-test was used for pre and post intervention comparison. Results: There was a significant increase in the tissue saturation index (TSI) in the trapezius muscle (80.7±2.7% vs. 89.4±4.6%; p= 0.002) in the pre and post intervention comparison. The pre-post variation delta of oxyhemoglobin - O2Hb (8.1±11.2 g/dL), deoxyhemoglobin - HHb (-0.72±1.6 g/dL) and total hemoglobin - tHB (7.4±12.3 g/dL) showed no significant difference. However, there was an increase in O2Hb, tHB levels and a decrease in HHb. Conclusion: The findings showed that the MFR applied on trapezius muscle increased the TSI, which reflects on peripheral muscle oxygenation in subjects without pain in the day of evaluation. [ABSTRACT FROM AUTHOR]

Methanotrophy of arable soils is affected by N fertilization, but the knowledge about the effect of oxygen level is poorly understood; soil aeration can fluctuate and zones of low oxygen are widespread in soil. We monitored CH4 oxidation in three mineral soils (Eutric Cambisol, Haplic Podzol, Mollic Gleysol) under laboratory conditions by varying the O2 level (from 20 to 2% O2), with or without NH4+ (100 mg N kg−1). In controls (without NH4+), CH4 was oxidized completely in the O2 range from oxia (20% O2) to high hypoxia (5% O2), while the process was inhibited under microoxia (2% O2). Ammonium application decreased CH4 consumption in all soils. This negative effect was stronger at 20% and 2% O2 than under hypoxia. The highest CH4 oxidation rates and the shortest initial (lag) phases in both control and NH4+-amended soils were observed under high (5% O2) and low (10% O2) hypoxia. [ABSTRACT FROM AUTHOR]

Our understanding of the effects of temperature on granulosa cell (GC) physiology is primarily limited to in vitro studies conducted under atmospheric (∼20% O 2 ) conditions. In the current series of factorial experiments we identify important effects of O 2 level (i.e. 5% vs 20% O 2 ) on GC viability and steroidogenesis, and go onto report effects of standard (37.5 °C) vs high (40.0 °C) temperatures under more physiologically representative (i.e. 5%) O 2 levels in the presence of different levels of melatonin (0, 20, 200 and 2000 pg/ml); a potent free-radical scavenger and abundant molecule within the ovarian follicle. Cells aspirated from antral (4–6 mm) follicles were cultured in fibronectin-coated wells using serum-free M199 for up to 144 h. At 37.5 °C viable cell number was enhanced and luteinization reduced under 5 vs 20% O 2 . Oxygen level interacted (P < 0.001) with time in culture to affect aromatase activity and cell estradiol (E 2 ) production (pg/mL/10 5 cells). These decreased between 48 and 96 h for both O 2 levels but increased again by 144 h for cells cultured under 5% but not 20% O 2 . Progesterone (P 4 ) concentration (ng/mL/10 5 cells) was greater (P < 0.001) under 20 vs 5% O 2 at 96 and 144 h. Cell number increased (P < 0.01) with time in culture under 5% O 2 irrespective of temperature. However, higher doses of melatonin increased viable cell number at 40.0 °C but reduced viable cell number at 37.5 °C (P = 0.004). Melatonin also reduced (P < 0.001) ROS generation at both O 2 levels across all concentrations. E 2 increased with time in culture at both temperatures under 5% O 2 , however P 4 declined between 96 and 144 h at 40.0 but not 37.5 °C. Furthermore, melatonin interacted (P < 0.001) with temperature in a dose dependent manner to increase P 4 at 37.5 °C but to reduce P 4 at 40.0 °C. Transcript expression for HSD3B1 paralleled temporal changes in P 4 production, and those for HBA were greater at 5% than 20% O 2 , suggesting that hemoglobin synthesis is responsive to changes in O 2 level. In conclusion, 5% O 2 enhances GC proliferation and reduces luteinization. Elevated temperatures under 5% O 2 reduce GC proliferation and P 4 production. Melatonin reduces ROS generation irrespective of O 2 level and temperature, but interacts with temperature in a dose dependent manner to influence GC proliferation and luteinization. [ABSTRACT FROM AUTHOR]

In this study, comparative studies on Sn whisker growth in Sn-0.3Ag-0.7Cu-1Pr solder under different environments were conducted to investigate factors like ambient temperature, oxygen level, and 3.5 wt% NaCl solution on whisker growth. The experimental results revealed that ambient temperature and oxygen level are two important factors that could determine the oxidation rate of PrSn 3 phase, thus indirectly affecting the growth rate of Sn whiskers. In addition, mechanisms of whisker growth under these three environments were established from the perspective of atom diffusion based on the “compressive stress-induced” theory. Although whiskers under different environments were all squeezed out from Pr oxides (hydroxides), the forms of their driving forces were different. For whiskers squeezed out in air whether at room temperature or 150 °C, the driving force is the compressive stress produced by lattice expansion due to the oxidation of PrSn 3 phase. The representative example was whiskers' growth at 150 °C, which could be simplified as three stages: (1) squeezing out, (2) cracking and (3) bursting out. For whisker growth in 3.5 wt% NaCl solution, the driving force for much fewer whiskers' growth was proposed to come from lateral stress provided by interfacial IMC layer growth. Moreover, Sn nanoparticles and their agglomerations were also found to form under the driving force of the potential difference between Sn atoms and Sn crystals. Their morphologies could also be affected by factors of ambient temperature, oxygen level and Cl − ions in corrosive liquid. [ABSTRACT FROM AUTHOR]

Recently, COVID-19 becomes a hot topic and explicitly made people follow social distancing and quarantine practices all over the world. Meanwhile, it is arduous to visit medical professionals intermittently by the patients for fear of spreading the disease. This IoT-based healthcare monitoring system is utilized by many professionals, can be accessed remotely, and provides treatment accordingly. In context with this, we designed an IoT-based healthcare monitoring system that sophisticatedly measures and monitors the parameters of patients such as oxygen level, blood pressure, temperature, and heart rate. This system can be widely used in rural areas that are linked to the nearest city hospitals to monitor the patients. The collected data from the monitoring system are stored in the cloud-based data storage and for the classification our approach proposes an innovative Recurrent Convolutional Neural Network (RCNN) based Puzzle optimization algorithm (PO). Based on the outcome further treatments are made with the assistance of physicians. Experimental analyses are made and analyzed the performance with state-of-art works. The availability of more data storage capacity in the cloud can make physicians access the previous data effortlessly., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Abstract The ability of soil to uptake methane is regulated by several factors affecting soil microbial activity. The soil oxygen concentration is usually lower than the concentration of atmospheric air, and nitrogen fertilization contributes to a significant increase in nitrate-N in soil. Therefore, we selected three agricultural soils (Eutric Cambisol, Haplic Podzol, Mollic Gleysol) to investigate interactive effects of oxygen and nitrate (KNO 3) on CH 4 oxidation including different gradients of O 2 (20%, 10%, 5%, 2%) and nitrate (0, 100, 200 mg N kg−1). The soils varied in their response to O 2 and nitrate treatments. In the absence of nitrate, all soils completely oxidized added CH 4 (1%) under the oxygen concentrations used (except 2%O 2); however, low oxygen (5%; 10%O 2) was optimal. Both nitrate doses strongly stimulated methane oxidation at 2%O 2 in Podzol and Gleysol, but generally inhibited CH 4 uptake in Cambisol. Highlights ⁃ Hypoxia (5%; 10%O 2) was optimal for CH 4 uptake in Podzol and Gleysol with NO 3 − ⁃ NO 3 − negatively affected CH 4 uptake in Cambisol at 20%, 10%, and 5%O 2 ⁃ Nitrate stimulated CH 4 uptake in three soils under 2%O 2 [ABSTRACT FROM AUTHOR]