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The incidence of total elbow arthroplasty (TEA) is increasing, and an improved understanding of elbow kinematics and biomaterials has driven advances in implant design. In modern practice, cemented, semiconstrained devices are most frequently used. The Discovery TEA has demonstrated promising early results, although there are a paucity of follow-up studies and no dedicated mid- to long-term series. We therefore present the longest, most complete such study to date. A prospectively maintained local joint registry was interrogated to yield a consecutive series of Discovery TEAs performed at a single non-design center. The minimum follow-up period was set at 5 years. Revision procedures and TEAs performed for acute trauma were excluded. The primary outcome was survivorship of the implant. The secondary outcomes included clinical, radiographic, and patient-reported outcomes. We identified 67 TEAs in 58 patients for inclusion at a mean of 98.5 ± 20.4 months from surgery. Four cases (6%) were lost to follow-up, and implant survival was censored accordingly. The implant was revised in 14 cases (20.9%). The Kaplan-Meier method showed an implant survivorship rate of 76.8% at 119 months. A significant difference in survival was found between dominant and nondominant elbows (P =.012, Breslow test), with elbow dominance conferring a 4.5-fold increased risk of revision (relative risk, 4.5; 95% confidence interval, 1.1-18.5). Pooled clinical outcomes (70.9% follow-up at minimum of 60 months and median of 77.8 months) were also determined. We present the longest-term and most complete single-center follow-up study of the Discovery TEA to date. Further long-term survival studies are required to elucidate the performance of this implant compared with more established designs. We have also demonstrated differences in implant survivorship owing to hand dominance for the first time. [ABSTRACT FROM AUTHOR]

Since the introduction of modern total elbow arthroplasty (TEA), there has been a rapid evolution in the understanding of elbow biomechanics, surgical techniques, and improvements in implant materials and design. Aimed originally to treat primarily end-stage rheumatoid arthritis, the indications for TEA have extended to include post-traumatic arthritis, primary osteoarthritis and acute non-reconstructable fractures of the distal humerus. Implant survivorship in TEA is substantially longer in patients with inflammatory arthritis when compared to trauma-related indications. The leading causes of revision are infection, aseptic loosening secondary to polyethylene wear and mechanical failure, and periprosthetic fractures. This article aims to provide an overview on revision TEA and the challenges associated with management of failed primary elbow arthroplasty. [ABSTRACT FROM AUTHOR]

The Chhatrapur placer deposit is found in a high background radiation area which has been recently identified on the southeastern coast of India. Previously, some geochemical studies of this area were carried out to assess external dose from radionuclides-bearing heavy mineral sands. In this study, radon, thoron and thoron progeny concentrations were measured in about 100 dwellings during three seasons (autumn-winter, summer, and rainy) in a 10- to 12-month period and annual doses due to inhalation of them were evaluated. The measurements were made by passive-type radon-thoron discriminative detectors and thoron progeny detectors in which solid state nuclear track detectors were deployed. The results show that radon and thoron concentrations differ by one order of magnitude depending on exposure periods, while thoron progeny concentration is nearly constant throughout the year. Since thorium-rich sand is distributed in the studied area, exposure to thoron is equal to, or exceeds, exposure to radon and is not negligible for dose evaluation. Based on the measurements, doses due to inhalation of radon and thoron are evaluated as 0.1–1.6 mSv y −1 and 0.2–3.8 mSv y −1 , respectively. The total dose is 0.8–4.6 mSv y −1 , which is the same order of magnitude as the worldwide value. [ABSTRACT FROM AUTHOR]

Abstract: The indoor radon concentration was estimated based on the radon flux in soil and groundwater. The indoor radon concentration in Budhakedar area of Garhwal Himalaya, India is estimated to be 3.0–131.4Bq/m3 in summer and 4.6–92.4Bq/m3 in winter. Based on the available data from study area, the calculated value of diffusion coefficient for the soil ranges from 0.1×10−2 to 3.0×10−2 cm2 s−1 in the summer season and 0.1×10−2 to 0.4×10−2 cm2 s−1 in the winter season. The calculated value of diffusion flux in the study area is found to vary from 0.1×10−2 to 16.1×10−2 Bqm−2 s−1 in summer season and 0.1×10−2–12.2×10−2 Bqm−2 s−1 in winter season. The formulation was tested by comparing the results of radon values from two different seasons of a year. [Copyright &y& Elsevier]

Abstract: The assessment of radiological risk related to inhalation of radon and radon progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth crust and building materials forms the main source of radon in indoor environment. In this comparative study, the indoor radon level was measured using twin cup dosimeter in different dwellings of Garhwal Himalayas. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of radon exhalations rate. The radon exhalation rate was measured in the laboratory using LR-115 type II plastic track detectors. The indoor radon concentrations in this study area were found to vary from 13±3Bq/m3 to 178±8Bq/m3 with an average of 61±5Bq/m3 while thoron concentration was found to vary 9±2Bq/m3 to 94±6Bq/m3 with an average of 33±3Bq/m3. The radon exhalation rate was found to vary from (0.43±0.05)×10−5 Bqkg−1 h−1 to (20.10±0.11)×10−5 Bqkg−1 h−1 with an average of (1.95±0.10)×10−5 Bqkg−1 h−1. The detail significance of this study is discussed in radiation protection point of view. [Copyright &y& Elsevier]

Abstract: The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fractured planes of bedrock. In this study, radon concentration in springs and hand pumps of Kumaun and Garhwal Himalaya, India was measured using radon emanometry technique. The study shows that radon concentration in springs and hand pumps is controlled by geohydrological characteristics, which in turn is also governed by tectonic processes. [Copyright &y& Elsevier]

Abstract: Ionizing radiation exposure experienced by the general population is mainly due to the indoor radon. Major part of radon comes from the top layer of the earth. The radon emanation is associated with radon in soil and sleepy back radium in the soil. Both field and laboratory measurements were carried out for the instantaneous and integrated radon concentration in soil-gas. The radon exhalation rate from collected soil samples was measured using LR-115 Type II plastic track detector. The soil-gas radon concentration was measured with the help of radon Emanometry method. The effective radium content of the soil samples was also calculated. The correlation coefficient between radium contents in collected soil samples and soil-gas radon from the same locations was calculated as 0.1, while it is 0.2 between radon exhalation rate and soil-gas radon concentration. The results show weak positive correlation due to the geological disturbance in the equilibrium conditions and high mobility of radon in the same geological medium. [Copyright &y& Elsevier]

Abstract: Environmental radiation exists as a consequence of cosmic, terrestrial and man made sources. Terrestrial radiation are emitted from natural radionuclide present in varying amounts in all types of soils, rocks, air, water and other environmental materials; radon is emitted from the soil surface, although secondary contributors include the oceans, natural gas, geothermal fluids, volcanic gases, ventilation from caves and mines, and combustion of coal. Radon and thoron levels were measured in soil-gas, ground water and indoor air in Budhakedar area of Tehri Garhwal, India. Radon concentrations in soil and groundwater of the Budhakedar area were found to vary from to with an average value and to with mean value , respectively. Measurement of indoor radon, thoron and their daughter products were also measured in the houses of the same area for four different seasons (autumn, winter, summer and rainy) using LR–115 plastic track detectors. The detector is fixed in a twin chamber radon dosimeter, which can record the values of radon, thoron and their decay products separately. The film fixed in bare mode holder gives the concentrations of radon, thoron and their progeny while the films fixed inside the cup with filter and membrane modes give the concentrations of radon/thoron gases and of pure radon gas, respectively. Detailed analysis of the effects of seasonal variation on radon, thoron and their decay products inside the houses are reported in this paper. [Copyright &y& Elsevier]

In most of the epidemiological studies contemporary radon measurements have been used as surrogates for radon concentrations in past decades even though changes in radon levels and residence may have occurred. Short-lived radon progeny may deposit on available surfaces in dwellings thus giving rise over time to a build up of long-lived progeny. Airborne radon decay products can be deposited and implanted through alpha recoil into the glass surfaces. On glass surface, activities of 210Po may arise as a result of the decay of recoil implanted activity following the alpha decay of surface deposited 218Po or 214Po. Measurement of 210Po implanted on a household glass is a method that can be employed to retrospectively determine the historic level of radon in dwellings. This method is based on the assumption that levels of recoil implanted 210Po in the glass provide a measure of time integrated radon concentration in the environment in which the glass has been located. The surface deposited activity of the radon progenies, which then become implanted in the glass by alpha recoil, is believed to reflect past exposure to airborne activity. Such retrospective measurements on glass are valuable in estimating the human dose derived from radon during the time of exposure. In this paper an account is given of the principles and some field applications of a retrospective technique, using the alpha track detectors, CR-39 and LR-115, to measure 210Po implanted in glass surfaces (surface traps). By using this CR–LR difference technique, the cumulative radon exposure in a dwelling in past decades may be estimated. This method provides reliable radon exposure data as a support to epidemiological studies concerning the health effects of radon exposure in the living environment. [Copyright &y& Elsevier]

Abstract: Research on earthquake-related radon monitoring has received enormous attention recently. Anomalous behaviour of radon in soil and groundwater can be used as a reliable precursor for an impending earthquake. While earthquake prediction may not yet be possible, earthquake prediction research has greatly increased our understanding of earthquake source mechanisms, the structural complexities of fault zones, and the earthquake recurrence interval, expected at a given location. This paper presents some results of continuous monitoring of radon in soil-gas in Garhwal Himalaya, India. Daily soil-gas radon monitoring with seismic activity and meteorological parameters were performed in the same laboratory system, located at H.N.B. Garhwal University Campus, Tehri Garhwal, India. Radon anomalies along with meteorological parameters were found to be statistically significant for the seismic events within the magnitudes M2.0-M6.0 and epicentral distances of 16–250km from the monitoring station. The frequent positive and negative anomalies with constant environmental perturbation indicate the opening and closing of micro cracks within the volume of dilatancy by strain energy. The spike-like and sharp peak anomalies were recorded before, during and after earthquakes occurred in the area. The variations in radon concentrations in soil-gas are found to be correlated with seismic activities in the Garhwal Himalaya. The correlation between radon level and meteorological parameters is also discussed. [Copyright &y& Elsevier]

For the efficient user scheduling (US) and interference mitigation, channel state information (CSI) is mandatory at the base station (BS), particularly for the frequency division duplexing (FDD) systems where the users need to provide some CSI back to the BS for performing the scheduling process. As the feedback overhead increases drastically with increase of antennas as well as users, so, US with limited/reduced feedback is essential. Deploying massive multiple-input multiple-output frequency division duplexing (mMIMO FDD) systems remains an open area for research with major difficulties of associated uplink CSI feedback load as the downlink and uplink channels are not reciprocal. Therefore, smart balancing is required between feedback data and achievable throughput while scheduling the users. In order to handle the above mentioned issue, we employed a selective 4-bit quantized CSI feedback based user-antenna paired/joint scheduling scheme for the multi user (MU) FDD mMIMO systems. The key idea involves in this process is that, only a limited set of users qualifying a predefined selection threshold feed back the 4-bit quantized signal-to-interference-plus-noise ratio (SINR) values based on angle-of-departure (AoD) along with the antenna indices for the scheduling process. The BS schedules the users with respective best antenna. Furthermore, using this scheme the multi user diversity gain is also achieved. This dynamic adjustment of antenna/user selection and collision free antenna sharing between the users majorly helps in improving the throughput of the system with this selective 4-bit quantized limited feedback. The mathematical sum rate performance analysis has been demonstrated along with simulation results for different system parameters. [ABSTRACT FROM AUTHOR]

A two element multiband multiple-input multiple-output (MIMO) antenna system with low specific absorption rate is proposed for Ka-band space satellite, millimeter-wave (mm-wave), fifth-generation (5G), and future sixth-generation (6G) wireless communication applications. The essential characteristics of both 5G and future 6G communications can be fulfilled by the proposed MIMO antenna design. The proposed MIMO antenna system has significant advantage of covering four relevant and usable frequency bands, i.e., 16 GHz, 25.5 GHz, 28 GHz, and 32 GHz used for the above mentioned applications. The design of the presented antenna looks like a vertical Yagi-Uda antenna with L-shaped ladder. Moreover, two circular slots and a slotted vertical stub are etched in a partially shared ground. The complete electrical dimension of the presented antenna is 6.8 λ 0 × 5. 7 λ 0 × 0. 068 λ 0 , calculated at resonating frequency 25.5 GHz, where λ 0 is wavelength in free space. The geometry of the presented antenna is fabricated using Rogers RO4350TM with dielectric constant (ϵ r) of 3.48, a loss tangent of 0.0025, and the substrate thickness of 0.8 mm. The presented MIMO antenna is excited with a 3 mm wide microstrip feed line having 50 Ω characteristics matched impedance. In terms of performance, the proposed antenna has achieved a reflection coefficient < - 10 dB, and isolation < -15 dB in all the resonating bands, radiation efficiency varies 72%–84%, impedance bandwidth of 4.6 GHz, 1.5 GHz, 1.11 GHz, and 7.5 GHz, and realized gain of 10.18, 12.05, 13.07, & 5.55 dBi is also achieved at frequencies 16 GHz, 25.5 GHz, 28 GHz, and 32 GHz. The achieved values for various MIMO matrices are envelope correlation coefficient > 0.0048, diversity gain of 9.98 dB, channel capacity loss < 0.00023 bits/s/Hz, and mean effective gain < -6 dB. The simulated results obtained by ANSYS I 2022 R2 (HFSS) and the experimental results measured by vector network analyzer (VNA) show a good agreement. [ABSTRACT FROM AUTHOR]

This article investigates a six-port multiple-input multiple-output antenna which operates in mid-bands with a resonating frequency at 4.8 GHz. The overall dimensions of proposed antenna are 0.60 λ 0 × 1. 32 λ 0 × 0. 024 λ 0 , where λ 0 is free space wavelength corresponding to resonating frequency of 4.8 GHz. The proposed geometry consists of six-port electromagnetic wave components along with a plane rectangular patch, slotted partial ring ground, circular cutting ground plane, and inset feeding. For enhancing isolation, I-shaped stubs and slotted ring ground are responsible. Inset feeding, circular cutting ground plane, and partial ground plane are used for enhancing reflection coefficient. The overall −10 dB impedance bandwidth of proposed antenna is ranging from 3.92 GHz to 5.2 GHz. The achieved isolation between all the ports of proposed work is ¿15 dB. The peak values of gain and radiation efficiency provided by this prototype are 6.45 dB & and 86% respectively. The achieved diversity parameters such as envelope correlation coefficients are ¡0.002, diversity gain is 9.98, channel capacity loss is ¡0.014 bits/sec/Hz, and branch power ratio is ¡−1 dB. The proposed antenna can be considered as a suitable candidate for wireless local area network, n77 bands, 5G wireless communications applications, and C-band operations. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the results of investigation of radon levels in the soil–gas and groundwater of Uttarkashi, India within the distance of 5km in vertical and horizontal directions from the landslide of Varunawat hill. Radon release from the soil and groundwater was found higher than the normal values. Radon concentration in groundwater over and around the landslide was found to vary from 0.51 to . The soil–gas radon concentration was found to vary from 219 to along the slope of landslide. Radon exhalation rate in collected soil samples was found to vary from to . Radon values were not found correlated with major and trace element contents in the upper soil of the area, which indicate that the migration of radon from deeper part of the earth along with landslide contribute to the surface radon concentration. Recorded values show a close association with local geology and Varunawat eruptions. [Copyright &y& Elsevier]

Abstract: Radon concentrations in groundwater and soil–gas along with the terrestrial gamma radiation dose rate have been measured in the different geological formation of Kumaon Himalaya, India. Radon concentrations were found to vary from 1 to 392Bq/l with a mean of 50Bq/l in water and to with a mean value of 5.867kBq/m3 in soil–gas. The radium content in collected groundwater samples from the study area was found to vary from 0.11 to 0.75Bq/l with a mean value 0.35Bq/l. The terrestrial gamma radiation dose rate and uranium content in soil were found to vary from 21.67 to with a mean value of and 0.8 to 15.3ppm with a mean value 3.4ppm, respectively, in different lithotectonic units. The emanation of radon in groundwater and soil–gas are found to be controlled by the geological formation of the area. It was also found to be controlled by the tectonic structure of the area. Radon level was found higher in the area consisting of granite, quartz porphyry, schist, phyllites slates and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks. The terrestrial gamma radiation dose rate in the area was found positively correlated with radon concentrations in groundwater and soil–gas. A strong positive correlation was observed between uranium content in soil and terrestrial gamma radiation dose rate. Soil–gas radon concentration was also found positively correlated with the uranium content in the soil. However, a weak correlation was found between uranium content in soil and radon concentrations in groundwater samples from the study area. No correlation was observed between radon concentrations in groundwater and soil–gas. [Copyright &y& Elsevier]

Abstract: In present investigation, newly designed twin cup pin-hole dosimeter with LR-115 track detector has been used for the integrated measurements of radon and thoron in the environmental air of a high background radiation area in coastal Orissa. The twin cup dosimeters were calibrated before installation in the field. The calibration experiment was made in an inter calibration exercise at NIRS, Chiba, Japan. The resulting calibration factors were used to obtain the values of radon and thoron in the study area. Radon and thoron concentrations in the houses of study area were found to vary from 24 Bq/m3 to 98 Bq/m3 and 46 Bq/m3 to 689 Bq/m3, respectively. The indoor and outdoor gamma dose rates in the study area vary from 0.124 μGy/h to 0.257 μGy/h and 0.109 μGy/h to 0.361 μGy/h, respectively. The annual effective dose due to the exposure to indoor radon and progeny was found to vary from 0.70 mSv to 2.84 mSv with an average value of 1.73 mSv. However, the annual effective dose due to the exposure to thoron and progeny was found to vary from 1.16 mSv to 17.36 mSv with an average value of 7.36 mSv. Thoron concentration and gamma dose rate were found relatively higher in the area. [Copyright &y& Elsevier]