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In this study, we investigated whether monitoring the ventral tail base surface temperature (ST) using a wearable wireless sensor could be effective for fever detection in calves with experimentally induced pneumonia after inoculation with Histophilus somni strain 2336. We found a significant difference in the changes in ST values between the control and H. somni-inoculated groups after 24 h of inoculation and detected fever; however, the rectal temperature showed a significant difference between the groups after 12 h of inoculation. When a significant difference in the ST between the two groups was observed, serum haptoglobin concentration and exacerbation of clinical score increased in the H. somni-inoculated group compared with those in the control group. Pneumonia was observed in the H. somni-inoculated group at necropsy, indicating that the changes in ST may reflect fever with inflammation caused by H. somni infection. Our results demonstrated that monitoring ST using a sensor attached to the ventral tail base can detect fever in calves and may be a useful and labor-saving tool for the health management of calves.
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Enfermedades de los Bovinos , Neumonía , Animales , Bovinos , Cola (estructura animal) , Temperatura , Neumonía/veterinaria , Fiebre/veterinaria , Vacunación/veterinaria , Enfermedades de los Bovinos/diagnósticoRESUMEN
Adsorption reactions of various cations on clay minerals have different effects on their environmental behaviors depending on the molecular-scale adsorption structure. Some cations form outer-sphere complexes via hydration, while others create inner-sphere complexes through dehydration. This preference dictates their environmental impact. However, the factors controlling these complex formations remain unclear. Furthermore, research on the adsorption preferences of radium (Ra) is lacking. Thus, this study conducted the first EXAFS study of Ra2+ adsorbed on clay minerals and showed that Ra2+ forms inner-sphere complexes on vermiculite, which can be surprising because Ra2+ is a divalent cation and prefers to be hydrated. In order to investigate the factors controlling the complex formations, this study conducted systematic EXAFS measurements and DFT calculations for alkali and alkaline earth metal cations. The results showed the importance of the size-matching effect between the adsorbed cation and the cavity of the tetrahedral sheets and that the complex formation can be estimated by the combination of the ionic radius and hydration enthalpy of the adsorbed cation. Furthermore, this study also analyzed environmental core samples. Their results showed the fixation of Ra2+ by clay minerals and the controlling factors can effectively predict cation environmental behavior.
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ABSTRACT: To discharge waste liquid containing radioactive iodine into sewage systems, long-term storage or dilution with a large amount of water may be required until the radioactivity concentration reduces below the standard value. Processing the waste liquid could be easier if radioactive iodine could be separated from the water. This study verified the effectiveness of superabsorbent polymer and α-cyclodextrin as treatment agents to separate radioactive iodine from waste liquids. Sodium iodide (Na 125 I) was added to purified water and artificial urine to prepare simulated waste liquids containing iodine equivalent to the urine of patients treated with radioactive iodine. The as-prepared simulated waste liquid was poured into a container with superabsorbent polymer and left for 90 d. The residual iodine rate in the simulated waste liquid was estimated by measuring 125 I radioactivity. When the water was sufficiently dried, residual iodine rates on day 15 were 0.102 and 0.884 in the simulated waste liquids comprising purified water and artificial urine, respectively. The simulated waste liquid comprising purified water with 5% α-cyclodextrin absorbed by 1 g of superabsorbent polymer had a residual rate of 0.980. Moreover, the residual rate of simulated waste liquid comprising artificial urine with 2% α-cyclodextrin absorbed by 1 g of SAP was 0.949. Superabsorbent polymer combined with α-cyclodextrin was an effective treatment agent for separating radioactive iodine from waste liquids.
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Estudios de Factibilidad , Radioisótopos de Yodo , alfa-Ciclodextrinas , alfa-Ciclodextrinas/química , Polímeros/química , Humanos , Residuos Radiactivos/análisis , Contaminantes Radiactivos del Agua/aislamiento & purificación , Contaminantes Radiactivos del Agua/análisisRESUMEN
Radiocesium released by the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident still exists in the environment in two forms: adsorbed species on mineral particles in the soil and microparticles containing radiocesium mainly composed of silicate glass (CsMPs). CsMPs are dispersed not only around the FDNPP but also over a wide area of the Kanto region. The behavior and characteristics of CsMPs must be investigated to evaluate the impact of the FDNPP accident. Deposited particles including radiocesium were wiped from metal handrails on balconies and car hoods using tissue papers at six locations in the Kanto region (Tokai village, Ushiku City, Abiko City, Chiba City, Kawaguchi City, and Arakawa Ward) between March 15 and 21, 2011. CsMPs were isolated from the samples, and their characteristics were investigated. In total, 106 CsMPs derived from Unit 2 were successfully separated from 13 tissue paper samples. The radiation images of the two types of CsMPs discovered in Ushiku City demonstrate that CsMPs can easily become susceptible to fragmentation over time, even in the absence of weathering effects.
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Accidente Nuclear de Fukushima , Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Contaminantes Radiactivos del Agua , Radioisótopos de Cesio/análisis , Japón , Contaminantes Radiactivos del Agua/análisis , Contaminantes Radiactivos del Suelo/análisis , Plantas de Energía NuclearRESUMEN
Elevated sperm mitochondrial DNA copy number (mtDNAcn) is associated with damage to sperm and poorer measures of semen quality. Exposure to cadmium (Cd) can increase oxidative stress and damage sperm mitochondria. The adverse effects of Cd can potentially be reduced by sufficient selenium (Se). The objective of this study was to examine the associations between sperm mtDNAcn and urinary concentrations of Cd and Se, as well as the Cd/Se molar ratio. Participants were recruited from patients who sought infertility treatment at two hospitals in Japan. Urine and semen specimens and self-administered questionnaires were collected on the day of recruitment. Sperm mtDNAcn was measured in extracted sperm DNA by multiplex real-time qPCR. Urinary Cd and Se concentrations were measured using inductively coupled plasma mass spectrometry, and their molar weights were calculated to obtain the Cd/Se molar ratio. Linear regression was used to estimate associations after adjusting for age, body mass index, smoking, drinking, exercise, varicocele, and hospital of recruitment. Sperm mtDNAcn showed statistically insignificant associations with creatinine-adjusted concentrations of urinary Cd (ß = 0.13, 95% CI -0.18, 0.44) and Se (ß = -0.09, 95% CI -0.54, 0.35), and Cd/Se molar ratio (ß = 0.12, 95% CI -0.13, 0.37). The current study found no evidence of an association between mtDNAcn and urinary concentrations of Cd or Se, or the Cd/Se molar ratio.
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ABSTRACT: The plume from Fukushima Dai-ichi Nuclear Power Plant (FDNPP) Unit 2, which reached the Tokyo metropolitan area on 15 March 2011 immediately after the FDNPP disaster, contained insoluble radiocesium-bearing microparticles (CsMPs). This study aimed to reanalyze a mask worn during the disaster to determine the ratio of CsMPs to radiocesium that directly arrived in the Tokyo metropolitan area as a plume immediately after the disaster. CsMPs were isolated from the non-woven masks worn at the Hongo Campus of the University of Tokyo from 15-16 March 2011 that trapped radioactive material from the accident. Twenty-two CsMPs with diameters in the range of 1.9-3.6 µm were found in the mask worn outdoors by one person. The CsMP radioactive ratio to overall radiocesium content of the mask was 9.9%. The CsMPs were collected more efficiently by the mask than by a suspended particulate matter filter. A face mask might trap CsMPs in a plume more efficiently than a suspended particulate matter filter. Determining the amount of CsMPs led to a reassessment of the internal dose by CsMPs that were inhaled by the public immediately after the FDNPP accident.
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Accidente Nuclear de Fukushima , Monitoreo de Radiación , Contaminantes Radiactivos del Agua , Humanos , Tokio , Radioisótopos de Cesio/análisis , Contaminantes Radiactivos del Agua/análisis , Material Particulado/análisis , Plantas de Energía Nuclear , JapónRESUMEN
A decade has passed since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident on March 11, 2011. However, radioactive particles have recently been detected in the indoor air of some residences near the FDNPP. Following the recommendations of previous research, we determined the presence of radiocesium-bearing microparticles (CsMPs) and measured the radioactivity of radiocesium that adhered on non-woven face masks worn by six persons during the indoor cleaning of 59 residences in Namie, Futaba, Okuma, and Tomioka towns in Fukushima Prefecture. Of the 284 masks worn in this study, significant 137Cs radioactivity was detected in 268, and 44 new CsMPs were discovered in 28. The results of this study also suggest the presence of highly concentrated soluble radiocesium particles or soluble radioactive cesium aerosols adhered to house dust. This implies that the CsMPs constituted a large proportion of radioactivity in the indoor air contamination for particles in the 1.0-2.5 µm size range due to the radioactive radiocesium particles. It is desirable to wear masks during cleaning to prevent inhalation of CsMPs.
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Accidente Nuclear de Fukushima , Monitoreo de Radiación , Contaminantes Radiactivos del Agua , Máscaras , Monitoreo de Radiación/métodos , Radioisótopos de Cesio/análisis , Cesio , Polvo , Plantas de Energía Nuclear , Japón , Contaminantes Radiactivos del Agua/análisisRESUMEN
It is desirable to attend to the mare at the time of foaling in order to assist fetal delivery and prevent complications. The early detection of the onset of labor is an important issue for the equine industry. The purpose of this study was to examine the applicability of a sensor for foaling detection using the data of surface temperature (ST), roll angle (rotation about the y-axis) and y-axis (long axis of the tail) acceleration which were collected from a multimodal device attached to the ventral tail base of the mare. The data were collected every 3 minutes in 17 pregnant mares. Roll angle differences from the reference values and the mare's posture (standing or recumbent) confirmed by video were compared and associated. Cohen's kappa coefficient was 0.99 when the threshold was set as ± 0.3 radian in roll angle differences. This result clearly showed that the sensor data can accurately distinguish between standing and recumbent postures. The hourly sensor data with a lower ST (LST < 35.5°C), a recumbent posture determined by the roll angle, and tail-raising (TR, decline of 200 mg or more from the reference value in y-axis acceleration) was significantly higher during the last hour prepartum than 2-120 hours before parturition (P < 0.01). The accuracy of foaling detection within one hour was verified using the following three indicators: LST; lying down (LD, change from standing to recumbent posture); and TR. When LST, LD and TR were individually examined, even though all indicators showed that sensitivity was 100%, the precision was 13.1%, 8.1% and 2.8%, respectively. When the data were combined as LST+LD, LST+TR, LD+TR and LST+LD+TR, detection of foaling improved, with precisions of 100%, 32.1%, 56.7% and 100%, respectively. In conclusion, the tail-attached multimodal device examined in this present study is useful for detecting foaling.
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Trabajo de Parto , Cola (estructura animal) , Embarazo , Caballos , Animales , Femenino , Parto , AcelerometríaRESUMEN
Tektins are a group of microtubule-stabilizing proteins necessary for cilia and flagella assembly. TEKTIN1 (TEKT1) is used as a sperm marker for monitoring germ cell differentiation in embryonic stem (ES) and induced pluripotent stem (iPS) cells. Although upregulation of TEKT1 has been reported during spontaneous differentiation of ES and iPS cells, it is unclear which cells express TEKT1. To identify TEKT1-expressing cells, we established an ES cell line derived from cynomolgus monkeys (Macaca fascicularis), which expresses Venus controlled by the TEKT1 promoter. Venus expression was detected at 5 weeks of differentiation on the surface of the embryoid body (EB), and it gradually increased with the concomitant formation of a leash-like structure at the EB periphery. Motile cilia were observed on the surface of the Venus-positive leash-like structure after 8 weeks of differentiation. The expression of cilia markers as well as TEKT1-5 and 9 + 2 microtubule structures, which are characteristic of motile cilia, were detected in Venus-positive cells. These results demonstrated that TEKT1-expressing cells are multiciliated epithelial-like cells that form a leash-like structure during the spontaneous differentiation of ES and iPS cells. These findings will provide a new research strategy for studying cilia biology, including ciliogenesis and ciliopathies.
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Primates , Semen , Animales , Masculino , Diferenciación Celular , Células Germinativas , Células Madre Embrionarias/metabolismoRESUMEN
Alpha-cyclodextrin, a six D-glucose cyclic oligosaccharide, has several applications in food and pharmaceuticals, but has also been reported to retain iodine in a stable manner for 16 months. Radioactive iodine, which may cause thyroid cancer and hypofunction, must be properly managed. If the absorption of radioactive iodine is suppressed, it can be expected to lead to a reduction in thyroid exposure. This study clarified the inhibition of radioactive iodine absorption by the oral administration of α-cyclodextrin in a murine model using direct measurement of single photon emission computed tomography. The uptake of radioactive iodine into the thyroid gland in mice administered with radioactive iodine and an α-cyclodextrin solution was approximately 40% lower after 24 h. The finding that oral uptake of α-cyclodextrin has an inhibitory effect on the transfer of radioactive iodine to the thyroid gland has potential for application in many fields such as food, pharmaceuticals, nuclear emergency preparedness, and medicine.
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Yodo , Neoplasias de la Tiroides , alfa-Ciclodextrinas , Animales , Ratones , Radioisótopos de Yodo , Administración Oral , Preparaciones FarmacéuticasRESUMEN
A 1.2 m flexible liquid scintillation light guide (LSLG) detector connected to a portable electric device was developed and applied to monitor X-rays scattered from a panoramic dental X-ray imaging apparatus. The X-ray absorption of the LSLG tube was simulated for 20 and 40 keV X-rays. The LSLG detector was calibrated by comparing doses measured by a 3-inch NaI(Tl) detector using Am-241 and Cs-137 sources. A linear relationship was obtained between dose rates (µSv/h) and count rates (cps). The elapsed time profile of scattered radiation from a panoramic dental X-ray imaging apparatus was determined. Local absorbed doses were measured with small OSL dosimeters on the LSLG tube suspended over the shoulder and the eyeglass. Behind the ears and neck (in the center of the LSLG tube) showed high doses. The LSLG detector was useful for real-time monitoring of scattered X-rays.
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Radioisótopos de Cesio , Rayos X , Radiografía Panorámica , RadiografíaRESUMEN
The present study investigated the applicability of a calving prediction model based on supervised machine learning of ruminal temperature (RT) data in dairy cows. The existence of cow subgroups for prepartum RT changes was also examined, and the predictive performance of the model was compared among these subgroups. RT data were collected from 24 Holstein cows at 10 min intervals using an RT sensor system. The average hourly RT was calculated and data were expressed as residual RTs (rRT = actual RT - mean RT for the same time on the previous three days). The mean rRT decreased beginning at approximately 48 h before calving to a low of -0.5°C at 5 h before calving. However, two cow subgroups were identified: cows with a late and small rRT decrease (Cluster 1, n = 9) and those with an early and large rRT decrease (Cluster 2, n = 15). A calving prediction model was developed using five features extracted from the sensor data (indicative of prepartum rRT changes) through a support vector machine. Cross-validation showed that calving within 24 h was predicted with a sensitivity of 87.5% (21/24) and precision of 77.8% (21/27). A significant difference in sensitivity was observed between Clusters 1 and 2 (66.7 vs. 100%, respectively), while none was observed for precision. Therefore, the model based on RT data with supervised machine learning has the potential to efficiently predict calving, although improvements for specific cow subgroups are required.
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Temperatura Corporal , Parto , Embarazo , Femenino , Bovinos , Animales , Temperatura , Aprendizaje Automático Supervisado , Análisis por Conglomerados , LactanciaRESUMEN
Nonylphenol (NP), an endocrine disrupting chemical, is widely used in industrial and agricultural processes, causing NP influx into aquatic environments. NP induces hormonal imbalance, and male feminization, and reduces germ cell production during spermatogenesis; however, the mechanism by which it affects spermatogenesis remains unknown. Here, we investigated the effect of NP on spermatogenesis in honmoroko (Gnathopogon caerulescens), an endangered fish endemic to Lake Biwa, Japan, using an in vitro differentiation system. We collected spermatogonia from the testes of non-spawning G. caerulescens and subjected them to suspension culture. The spermatogonia differentiated into flagellated spermatozoa in 3 weeks, regardless of the presence of NP. NP concentrations as low as 1 nM caused a decrease in the number of germ cells in a dose-dependent manner, whereas the number of somatic cells decreased only at a high concentration of 1 µM. Flow cytometric analysis revealed that the decrease in germ cell number was attributed to haploids (spermatids and spermatozoa); the number of spermatogonia and spermatocytes was not affected by NP treatment. This result is consistent with the hypothesis that NP might repress the second meiosis or induce apoptosis in haploids. This study demonstrated that the combination of in vitro germ cell differentiation and flow cytometric analysis is useful for evaluating the direct effects of NP on germ cell differentiation in endangered endemic fish.
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Cyprinidae , Espermatogénesis , Animales , Masculino , Haploidia , Espermatozoides , Espermatogonias , TestículoRESUMEN
In this study, we developed calving prediction models for 24-h and 6-h periods before calving using data on physiological (tail skin temperature) and behavioral (activity intensity, lying time, posture change, and tail raising) parameters obtained using a multimodal tail-attached device (tail sensor). The efficiencies of the models were validated under tethering (tie-stall) and untethering (free-stall and individual pen) conditions. Data were collected from 33 and 30 pregnant cattle under tethering and untethering conditions, respectively, from approximately 15 days before the expected calving date. Based on pre-calving changes, 40 features (8 physiological and 32 behavioral) were extracted from the sensor data, and one non-sensor-based feature (days to the expected calving date) was added to develop models using a support vector machine. Cross-validation showed that calving within the next 24 h under tethering and untethering conditions was predicted with a sensitivity of 97% and 93% and precision of 80% and 76%, respectively, while calving within the next 6 h was predicted with a sensitivity of 91% and 90% and precision of 88% and 90%, respectively. Calving prediction models based on the tail sensor data with supervised machine learning have the potential to achieve effective calving prediction, irrespective of the cattle housing conditions.
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INTRODUCTION: Production of 99Mo/99mTc using an electron linear accelerator (linac) and activated carbon (AC)-based 99mTc generator (linac-AC) is an alternative approach to the conventional fission production of 99Mo/99mTc. As a preliminary investigation of the clinical applicability of a linac-AC-derived 99mTc radiopharmaceutical, the biodistribution of linac-AC-derived [99mTc]sodium pertechnetate ([99mTc]NaTcO4) was measured and compared against fission-derived [99mTc]NaTcO4 at one time point. METHODS: 99Mo was produced by irradiating nonenriched MoO3 targets with bremsstrahlung photons generated from 55.5-MeV linac electron beams. 99mTc was then separated and purified from the 99Mo using an AC-based 99mTc generator. Subsequently, biodistribution of the linac-AC-derived [99mTc]NaTcO4 in healthy female Slc:ICR mice (n = 6) was measured by dissection and compared with that of fission-derived [99mTc]NaTcO4 (n = 4) at 30 min after injection. RESULTS: The two types of [99mTc]NaTcO4 exhibited similar biodistribution in all the organs and tissues examined: the uptakes of [99mTc]NaTcO4 prepared from the linac-AC method and those prepared from the fission method were 138.9 ± 69.9%ID/g and 160.6 ± 49.2%ID/g in the thyroids, respectively, 33.4 ± 5.5%ID/g and 29.4 ± 9.1%ID/g in the salivary glands, respectively, and less than 10%ID/g in blood and all the other organs. No adverse effects were observed in the mice administered with either [99mTc]NaTcO4. CONCLUSION: The clinical applicability of linac-AC-derived [99mTc]NaTcO4 was suggested by its similar biodistribution with fission-derived [99mTc]NaTcO4 at one time point. Further biodistribution studies at multiple time points are encouraged to demonstrate the bioequivalence between linac-AC- and fission-derived [99mTc]NaTcO4.
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Carbón Orgánico , Pertecnetato de Sodio Tc 99m , Animales , Electrones , Femenino , Ratones , Ratones Endogámicos ICR , Aceleradores de Partículas , Sodio , Distribución TisularRESUMEN
In this study, we determined the applicability of the background image subtraction technique to detect estrus in tie-stalled cows. To investigate the impact of the camera shooting direction, webcams were set up to capture the front, top, and rear views of a cow simultaneously. Video recording was performed for a total of ten estrous cycles in six cows. Standing estrus was confirmed by testing at 6 h intervals. From the end of estrus, transrectal ultrasonography was performed every 2 h to confirm ovulation time. Foreground objects (moving objects) were extracted in the videos using the background subtraction technique, and the pixels were counted at each frame of five frames-per-second sequences. After calculating the hourly averaged pixel counts, the change in values was expressed as the pixel ratio (total value during the last 24 h/total value during the last 24 to 48 h). The mean pixel ratio gradually increased at approximately 48 h before ovulation, and the highest value was observed at estrus, regardless of the camera shooting direction. When using front-view videos with an appropriate threshold, estrus was detected with 90% sensitivity and 50% precision. The present method in particular has the potential to be a non-contact estrus detection method for tie-stalled cows.
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Fishes expressing a fluorescent protein in germ cells are useful to perform germ cell transfer experiments for conservation study. Nonetheless, no such fish has been generated in endangered endemic fishes. In this study, we tried to produce a fish expressing Venus fluorescent protein in germ cells using Honmoroko (Gnathopogon caerulescens), which is one of the threatened small cyprinid endemic to the ancient Lake Biwa in Japan. To achieve germ cell-specific expression of Venus, we used piwil1 (formally known as ziwi) promoter and Tol2 transposon system. Following the co-injection of the piwil1-Venus expression vector and the Tol2 transposase mRNA into fertilized eggs, presumptive transgenic fish were reared. At 7 months of post-fertilization, about 19% (10/52) of the examined larvae showed Venus fluorescence in their gonad specifically. Immunohistological staining and in vitro spermatogenesis using gonads of the juvenile founder fish revealed that Venus expression was detected in spermatogonia and spermatocyte in male, and oogonia and stage I and II oocytes in female. These results indicate that the Tol2 transposon and zebrafish piwil1 promoter enabled gene transfer and germ cell-specific expression of Venus in G. caerulescens. In addition, in vitro culture of juvenile spermatogonia enables the rapid validation of temporal expression of transgene during spermatogenesis.
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Cyprinidae , Animales , Cyprinidae/genética , Femenino , Técnicas de Transferencia de Gen , Masculino , Espermatogonias , Pez Cebra/genéticaRESUMEN
A part of the radiocaesium from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident was emitted as glassy, water-resistant caesium-bearing microparticles (CsMPs). Here, we isolated and investigated seven CsMPs from marine particulate matter and sediment. From the elemental composition, the 134Cs/137Cs activity ratio, and the 137Cs activity per unit volume results, we inferred that the five CsMPs collected from particulate matter were emitted from Unit 2 of the FDNPP, whereas the two CsMPs collected from marine sediment were possibly emitted from Unit 3, as suggested by (i) the presence of calcium and absence of zinc and (ii) the direction of the atmospheric plume during the radionuclide emission event from Unit 3. The presence of CsMPs can cause overestimation of the solid-water distribution coefficient of Cs in marine sediments and particulate matter and a high apparent radiocaesium concentration factor for marine biota. CsMPs emitted from Unit 2, which were collected from the estuary of a river that flowed through a highly contaminated area, may have been deposited on land and then transported by the river. By contrast, CsMPs emitted from Unit 3 were possibly transported eastward by the wind and deposited directly onto the ocean surface.
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We aimed to determine the effectiveness of estrus detection based on continuous measurements of the ventral tail base surface temperature (ST) with supervised machine learning in cattle. ST data were obtained through 51 estrus cycles on 11 female cattle (six Holsteins and five Japanese Blacks) using the tail-attached sensor. Three estrus detection models were constructed with the training data (n = 17) using machine learning techniques (random forest, artificial neural network, and support vector machine) based on 13 features extracted from sensing data (indicative of estrus-associated ST changes). Estrus detection abilities of the three models on test data (n = 34) were not statistically different among models in terms of sensitivity and precision (range 50.0% to 58.8% and 60.6% to 73.1%, respectively). The relatively poor performance of the models might indicate the difficulty of separating estrus-associated ST changes from estrus-independent fluctuations in ST.
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Temperatura Corporal/fisiología , Detección del Estro/métodos , Aprendizaje Automático Supervisado , Animales , Bovinos , Detección del Estro/instrumentación , Femenino , Modelos Biológicos , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/veterinaria , Temperatura Cutánea/fisiología , Cola (estructura animal)/diagnóstico por imagen , Dispositivos Electrónicos VestiblesRESUMEN
In this study, we developed a calving prediction model based on continuous measurements of ventral tail base skin temperature (ST) with supervised machine learning and evaluated the predictive ability of the model in 2 dairy farms with distinct cattle management practices. The ST data were collected at 2- or 10-min intervals from 105 and 33 pregnant cattle (mean ± standard deviation: 2.2 ± 1.8 parities) reared in farms A (freestall barn, in a temperate climate) and B (tiestall barn, in a subarctic climate), respectively. After extracting maximum hourly ST, the change in values was expressed as residual ST (rST = actual hourly ST - mean ST for the same hour on the previous 3 d) and analyzed. In both farms, rST decreased in a biphasic manner before calving. Briefly, an ambient temperature-independent gradual decrease occurred from around 36 to 16 h before calving, and an ambient temperature-dependent sharp decrease occurred from around 6 h before until calving. To make a universal calving prediction model, training data were prepared from pregnant cattle under different ambient temperatures (10 data sets were randomly selected from each of the 3 ambient temperature groups: <15°C, ≥15°C to <25°C, and ≥25°C in farm A). An hourly calving prediction model was then constructed with the training data by support vector machine based on 15 features extracted from sensing data (indicative of pre-calving rST changes) and 1 feature from non-sensor-based data (days to expected calving date). When the prediction model was applied to the data that were not part of the training process, calving within the next 24 h was predicted with sensitivities and precisions of 85.3% and 71.9% in farm A (n = 75), and 81.8% and 67.5% in farm B (n = 33), respectively. No differences were observed in means and variances of intervals from the calving alerts to actual calving between farms (12.7 ± 5.8 and 13.0 ± 5.6 h in farms A and B, respectively). Above all, a calving prediction model based on continuous measurement of ST with supervised machine learning has the potential to achieve effective calving prediction, irrespective of the rearing condition in dairy cattle.