Accurate models and nutritional strategies for specific oxidative stress factors: Does the dose matter in swine production?

Oxidative stress has been associated with a number of physiological problems in swine,including reduced production efficiency.Recently,although there has been increased research into regulatory mechanisms and antioxidant strategies in relation to oxidative stress-induced pig production,it remains so far largely unsuccessful to develop accurate models and nutritional strategies for specific oxidative stress factors.Here,we discuss the dose and dose intensity of the causes of oxidative stress involving physiological,environmental and dietary factors,recent research models and the antioxidant strategies to provide theoretical guidance for future oxidative stress research in swine.

Helicobacter pylori:High dose amoxicillin does not improve primary or secondary eradication rates in an Irish cohort

BACKGROUND Helicobacter pylori(H.pylori)eradication rates have fallen globally,likely in large part due to increasing antibiotic resistance to traditional therapy.In areas of high clarithromycin and metronidazole resistance such as ours,Maastricht VI guidelines suggest high dose amoxicillin dual therapy(HDADT)can be considered,subject to evidence for local efficacy.In this study we assess efficacy of HDADT therapy for H.pylori eradication in an Irish cohort.AIM To assess the efficacy of HDADT therapy for H.pylori eradication in an Irish cohort as both first line,and subsequent therapy for patients diagnosed with H.pylori.METHODS All patients testing positive for H.pylori in a tertiary centre were treated prospectively with HDADT(amoxicillin 1 g tid and esomeprazole 40 mg bid×14 d)over a period of 8 months.Eradication was confirmed with Urea Breath Test at least 4 wk after cessation of therapy.A delta-over-baseline>4%was considered positive.Patient demographics and treatment outcomes were recorded,analysed and controlled for basic demographics and prior H.pylori treatment.RESULTS One hundred and ninety-eight patients were identified with H.pylori infection,10 patients were excluded due to penicillin allergy and 38 patients refused follow up testing.In all 139 were included in the analysis,55%(n=76)were female,mean age was 46.6 years.Overall,93(67%)of patients were treatment-naïve and 46(33%)had received at least one previous course of treatment.The groups were statistically similar.Self-reported compliance with HDADT was 97%,mild side-effects occurred in 7%.There were no serious adverse drug reactions.Overall the eradication rate for our cohort was 56%(78/139).Eradication rates were worse for those with previous treatment[43%(20/46)vs 62%(58/93),P=0.0458,odds ratio=2.15].Age and Gender had no effect on eradication status.CONCLUSION Overall eradication rates with HDADT were disappointing.Despite being a simple and possibly better tolerated regime,these results do not support its routine use in a high dual resistance country.Further investigation of other regimens to achieve the>90%eradication target is needed.

Determination of Timer Error and Evaluation of Its Effect on Dose for OB6, GammaBeam X200 and X-Ray Irradiators at the Secondary Standard Dosimetry Laboratory in Nigeria

Timer error as well as its convention is very important for dose accuracy during irradiation. This paper determines the timer error of irradiators at Secondary Standard Dosimetry Laboratory (SSDL) in Nigeria. The irradiators are Cs-137 OB6 irradiator and X-ray irradiators at the Protection level SSDL;and Co-60 irradiator at the Therapy Level SSDL. PTW UNIDOS electrometer and LS01 Ionization chamber were used at the Protection Level to obtain doses for both Cs-137 OB6 and X-ray irradiators while an IBA farmer type ionization chamber and an IBA DOSE 1 electrometer were used at the Protection Level SSDL. Single/multiple exposure method and graphical method were used in the determination of the timer error for the three irradiators. The timer error obtained for Cs-137 OB6 irradiator was 0.48 ± 0.01 s, the timer error for the X-ray irradiator was 0.09 ± 0.01 s while the timer error obtained for GammaBeam X200 was 1.21 ± 0.04 s. It was observed that the timer error is not affected by source to detector distance. It was also observed that the timer error of Co-60 Gamma X200 irradiator is increasing with the age of the machine. Source to detector distance and field size do not contribute towards the timer error of the irradiators. The timer error of the Co-60 Gamma X200 irradiator (the only irradiator among the irradiators with a pneumatic system) increases with the age of the irradiator.

Total ionizing dose effect modeling method for CMOS digital-integrated circuit

Simulating the total ionizing dose(TID)of an electrical system using transistor-level models can be difficult and expensive,particularly for digital-integrated circuits(ICs).In this study,a method for modeling TID effects in complementary metaloxide semiconductor(CMOS)digital ICs based on the input/output buffer information specification(IBIS)was proposed.The digital IC was first divided into three parts based on its internal structure:the input buffer,output buffer,and functional area.Each of these three parts was separately modeled.Using the IBIS model,the transistor V-I characteristic curves of the buffers were processed,and the physical parameters were extracted and modeled using VHDL-AMS.In the functional area,logic functions were modeled in VHDL according to the data sheet.A golden digital IC model was developed by combining the input buffer,output buffer,and functional area models.Furthermore,the golden ratio was reconstructed based on TID experimental data,enabling the assessment of TID effects on the threshold voltage,carrier mobility,and time series of the digital IC.TID experiments were conducted using a CMOS non-inverting multiplexer,NC7SZ157,and the results were compared with the simulation results,which showed that the relative errors were less than 2%at each dose point.This confirms the practicality and accuracy of the proposed modeling method.The TID effect model for digital ICs developed using this modeling technique includes both the logical function of the IC and changes in electrical properties and functional degradation impacted by TID,which has potential applications in the design of radiation-hardening tolerance in digital ICs.

Establishment of NaLuF_(4):15%Tb-based low dose X-PDT agent and its application on efficient antitumor therapy

X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration depth.However,high X-ray irradiation dose caused organ lesions and side effects became the major barrier to X-PDT application.To address this issue,this work employed a classic-al co-precipitation reaction to synthesize NaLuF_(4):15%Tb^(3+)(NLF)with an average particle size of(23.48±0.91)nm,which was then coupled with the photosensitizer merocyanine 540(MC540)to form the X-PDT system NLF-MC540 with high production of singlet oxygen.The system could induce antitumor efficacy to about 24%in relative low dose X-ray irradiation range(0.1-0.3 Gy).In vivo,when NLF-MC540 irradiated by 0.1 Gy X-ray,the tumor inhibition percentage reached 89.5%±5.7%.The therapeutic mechanism of low dose X-PDT was found.A significant increase of neutrophils in serum was found on the third day after X-PDT.By immunohistochemical staining of tumor sections,the Ly6G^(+),CD8^(+),and CD11c^(+)cells infiltrated in the tumor microenvironment were studied.Utilizing the bilat-eral tumor model,the NLF-MC540 with 0.1 Gy X-ray irradiation could inhibit both the primary tumor and the distant tumor growth.De-tected by enzyme linked immunosorbent assay(ELISA),two cytokines IFN-γand TNF-αin serum were upregulated 7 and 6 times than negative control,respectively.Detected by enzyme linked immune spot assay(ELISPOT),the number of immune cells attributable to the IFN-γand TNF-αlevels in the group of low dose X-PDT were 14 and 6 times greater than that in the negative control group,respectively.Thus,it conclude that low dose X-PDT system could successfully upregulate the levels of immune cells,stimulate the secretion of cy-tokines(especially IFN-γand TNF-α),activate antitumor immunity,and finally inhibit colon tumor growth.

利用Batch Implant机台离子注入dose梯度分布调控注入均匀性的技术分析

阐述发现batch implant机台所作业的wafer状况,在wafer面内存在规律性梯度差异的dose分布。基于wafer processing过程中的形变现象,通过fine tune beam line及优化diskangle条件,可以定量设计dose梯度分布情况。通过优化离子注入在wafer面内分布的dose对称性,可以有效改善离子注入均匀性。

High-dose methotrexate and zanubrutinib combination therapy for primary central nervous system lymphoma

In this editorial I comment on the article,published in the current issue of the World Journal of Clinical Oncology.Primary central nervous system lymphoma(PCNSL)is a disease of elderly and immunocompromised patients.The authors reported clinical results of 19 patients with PCNSL treated with zanubrutinib/high dose methotrexate(HD-MTX)until disease progression.They demonstrated that the combination of zanubrutinib with HD-MTX led to a marked clinical response and tolerability among these patients.They also observed that cerebrospinal fluid liquid biopsy to detect circulating tumor DNA may be a good option for evaluating treatment response and tumor burden in patients with PCNSL.PCNSL is a challenging disease for treatment as these patients present with different neurological states and comorbidities.Treatment has evolved over the years from whole brain radiotherapy to HD-MTX followed by autologous stem cell transplant.Gradually,treatment of patients with PCNSL is going to become individualized.

Predicting 3D Radiotherapy Dose-Volume Based on Deep Learning

Cancer is one of the most dangerous diseaseswith highmortality.One of the principal treatments is radiotherapy by using radiation beams to destroy cancer cells and this workflow requires a lot of experience and skill from doctors and technicians.In our study,we focused on the 3D dose prediction problem in radiotherapy by applying the deeplearning approach to computed tomography(CT)images of cancer patients.Medical image data has more complex characteristics than normal image data,and this research aims to explore the effectiveness of data preprocessing and augmentation in the context of the 3D dose prediction problem.We proposed four strategies to clarify our hypothesis in different aspects of applying data preprocessing and augmentation.In strategies,we trained our custom convolutional neural network model which has a structure inspired by the U-net,and residual blocks were also applied to the architecture.The output of the network is added with a rectified linear unit(Re-Lu)function for each pixel to ensure there are no negative values,which are absurd with radiation doses.Our experiments were conducted on the dataset of the Open Knowledge-Based Planning Challenge which was collected from head and neck cancer patients treatedwith radiation therapy.The results of four strategies showthat our hypothesis is rational by evaluating metrics in terms of the Dose-score and the Dose-volume histogram score(DVH-score).In the best training cases,the Dose-score is 3.08 and the DVH-score is 1.78.In addition,we also conducted a comparison with the results of another study in the same context of using the loss function.

GPU-based cross-platform Monte Carlo proton dose calculation engine in the framework of Taichi

In recent years,graphics processing units(GPUs)have been applied to accelerate Monte Carlo(MC)simulations for proton dose calculation in radiotherapy.Nonetheless,current GPU platforms,such as Compute Unified Device Architecture(CUDA)and Open Computing Language(OpenCL),suffer from cross-platform limitation or relatively high programming barrier.However,the Taichi toolkit,which was developed to overcome these difficulties,has been successfully applied to high-performance numerical computations.Based on the class II condensed history simulation scheme with various proton-nucleus interactions,we developed a GPU-accelerated MC engine for proton transport using the Taichi toolkit.Dose distributions in homogeneous and heterogeneous geometries were calculated for 110,160,and 200 MeV protons and were compared with those obtained by full MC simulations using TOPAS.The gamma passing rates were greater than 0.99 and 0.95 with criteria of 2 mm,2%and 1 mm,1%,respectively,in all the benchmark tests.Moreover,the calculation speed was at least 5800 times faster than that of TOPAS,and the number of lines of code was approximately 10 times less than those of CUDA or OpenCL.Our study provides a highly accurate,efficient,and easy-to-use proton dose calculation engine for fast prototyping,beamlet calculation,and education purposes.

Dose reconstruction with Compton camera during proton therapy via subset-driven origin ensemble and double evolutionary algorithm

Compton camera-based prompt gamma(PG) imaging has been proposed for range verification during proton therapy. However, a deviation between the PG and dose distributions, as well as the difference between the reconstructed PG and exact values, limit the effectiveness of the approach in accurate range monitoring during clinical applications. The aim of the study was to realize a PG-based dose reconstruction with a Compton camera, thereby further improving the prediction accuracy of in vivo range verification and providing a novel method for beam monitoring during proton therapy. In this paper, we present an approach based on a subset-driven origin ensemble with resolution recovery and a double evolutionary algorithm to reconstruct the dose depth profile(DDP) from the gamma events obtained by a cadmium-zinc-telluride Compton camera with limited position and energy resolution. Simulations of proton pencil beams with clinical particle rate irradiating phantoms made of different materials and the CT-based thoracic phantom were used to evaluate the feasibility of the proposed method. The results show that for the monoenergetic proton pencil beam irradiating homogeneous-material box phantom,the accuracy of the reconstructed DDP was within 0.3 mm for range prediction and within 5.2% for dose prediction. In particular, for 1.6-Gy irradiation in the therapy simulation of thoracic tumors, the range deviation of the reconstructed spreadout Bragg peak was within 0.8 mm, and the relative dose deviation in the peak area was less than 7% compared to the exact values. The results demonstrate the potential and feasibility of the proposed method in future Compton-based accurate dose reconstruction and range verification during proton therapy.

Bias Dose在脑转移肿瘤序贯放疗计划设计中的应用

目的:分析医科达Monaco计划系统的Bias Dose计划设计功能应用于脑转移肿瘤的序贯放疗计划设计的可行性及优缺点。方法:选择10例脑转移肿瘤患者,以同一首程计划为基础,分别使用常规方法和Bias方法(采用Bias Dose计划设计功能)设计再程计划,作为常规计划组和Bias计划组,比较2组计划的剂量分布情况、机器跳数及计划设计时间(包括优化时间和预估执行时间)。使用SPSS 22.0软件进行统计学分析。结果:相较于常规计划组,Bias计划组计划肿瘤区(planning gross tumor volume,PGTV)的D2偏高0.64%,计划靶区(planning target volume,PTV)的Dmean偏低1.18%,差异均具有统计学意义(P<0.05),且结果均在临床可接受范围。2组计划靶区覆盖率均在96%以上,危及器官受量均在临床限值内,差异均无统计学意义(P>0.05)。Bias计划组的适形性指数、PGTV靶区的均匀性指数、机器跳数和预估执行时间均高于常规计划组,PTV靶区的均匀性指数低于常规计划组,差异均具有统计学意义(P<0.05)。结论:应用Bias Dose计划设计功能设计脑转移肿瘤序贯放疗计划,虽然在机器跳数和预估执行时间方面有一定的劣势,但在靶区剂量分布方面具有一定的优势,同时也给计划设计和评估带来很大便利,因此在脑转移肿瘤序贯放疗中应采用Bias Dose计划设计功能以取得更优的剂量分布。

Factors Contributing to the Acceptability of Second Dose of Measles Vaccine among Children in Livingstone District, Zambia

Introduction: Measles is a viral disease that is a major public health problem in both developed and developing countries. It is a contagious disease resulting from infection with the measles virus and is still responsible for more than 100,000 deaths per year. Although vaccination is one of the most successful and cost-effective public health interventions to reduce mortality and morbidity, approximately 1.4 million children worldwide die from vaccine-preventable diseases each year. In Zambia, MCV2 was 66% below WHO recommended target of 95%. This study therefore assessed the acceptability of second dose measles vaccination services among caretakers/mothers with children less than two years of age in Livingstone, Zambia. Methods: The study used analytical cross-sectional study design. A logistic regression analysis was performed to identify factors associated with acceptability of the second dose of measles vaccine. A semi structured questionnaire was administered to collect data on socio demographic characteristics and factors related to acceptability of the second dose of measles vaccine. SPSS version 26.0 was used for descriptive and inferential analysis at 5% level of significance. Results: There was no statistically significant difference in acceptability of the second dose of measles vaccine by gender, marital status, type of employment, income level, socio-cultural and traditional beliefs, and education level. However, there was a statistically significant difference in acceptability of the second dose of measles vaccine by knowledge level of second dose of measles vaccine. A Chi square test result indicated that second dose acceptability was higher with less children than that of respondents with many children (χ2(5) = 15.3, p and knowledge levels (χ2(2) = 14.8, p Changes in knowledge level from medium to high reduced the odds of second dose measles vaccine acceptability. Furthermore, this study showed that acceptance of the second measles vaccination increased from mothers/caretakers with low knowledge (3.6%) to medium knowledge (13.3%) and finally high knowledge (83.1%). Conclusion: Tailored messaging to increase knowledge among mothers and caregivers on the importance of the second dose of measles vaccine is critical in improving acceptability. Therefore, the researchers recommend that the health providers should continue to raise awareness associated with the low acceptability of the second dose of measles vaccine and improve on child preventable diseases such as measles.

Simultaneous integrated dose reduction intensity-modulated radiotherapy effectively reduces cardiac toxicity in limited-stage small cell lung cancer

Objective:To assess the clinical outcomes and toxicities of once daily(QD)simultaneous dose reduction intensity-modulated radiotherapy(SDR-IMRT-QD;SDR-QD)versus conventional QD IMRT(C-QD)and twice daily(BID)IMRT in patients with limited-stage small cell lung cancer(LS-SCLC).Methods:After propensity score matching(PSM),a retrospective analysis involving 300 patients with LS-SCLC treated using SDR-QD,C-QD,or BID was performed from January 1,2014 to December 31,2019.The prescribed irradiation dose in the SDR-QD cohort was 60 Gy/PGTV and 54 Gy/PTV QD.The radiation dose was 60 Gy for both PGTV and PTV QD in the C-QD cohort.The radiation dose was 45 Gy for both PGTV and PTV in the BID cohort.Toxicities,short-term effects,and survival outcomes were recorded.A meta-analysis on the protective effects of pharmaceuticals for cardiac toxicities induced by anti-tumor therapy was performed.Results:The median overall survival time(MST)in the 3 cohorts were 32.7 months(SDR-QD),26.3 months(C-QD),and 33.6 months(BID);the differences between groups were statistically significant.Lower toxicities and doses to organs-at-risk(OARs)occurred in the SDR-QD and BID cohorts.Further,the cardiac dose dosimetric parameter Vheart40 was negatively associated with survival(r=-0.35,P=0.007).A Vheart40 value of 16.5%was recommended as a cut-off point,which yielded 54.7%sensitivity and 85.7%specificity for predicting negative survival outcomes.The meta-analysis indicated that pharmaceuticals significantly reduced the cardiac toxicities induced by chemotherapy,but not radiotherapy.Conclusions:SDR-QD was shown to have similar toxicities and survival compared with BID,but fewer toxicities and better survival than C-QD.In addition,cardiac dose exposure was negatively associated with survival.Thus,16.5%of the cardiac dosimetric parameter Vheart40 is recommended as the cut-off point,and a Vheart40>16.5%predicts poor survival.

Radiation Doses in Diagnostic Radiology and Method for Dose Reduction

Objective: The current research study aims to calculate entrance surface air kerma for skull, chest, cervical spine, lumbar spine, and pelvic X-ray examinations in interior posterior and posterior interior positions and generate a method for chest dose reduction to decrease radiation risk. Materials and Methods: The indirect dose measurement was used in the current research. The X-ray tube output was measured using RAD-CHECK Plus ionization chamber and the indirect entrance surface air kerma was calculated via applying physical acquisition parameters such as a focus on skin distance, tube current times exposure time (mAs), and applied tube voltage (kV), and applying a mathematical model. Results: The main findings were obtained from comparing the radiation doses with the reference levels of International organizations such as the American College of Radiology and the International Atomic Energy Authority. The mean entrance skin dose for the skull (AP), skull (PA), skull (LAT), cervical spine (PA), cervical spine (LAT), lumbar spine (AP), lumbar spine (LAT), pelvis (AP), and pelvis (LAT) of adult X-ray examinations was within the diagnostic reference dose level values obtained by ACR (2018) except for the ESD for chest (AP) which was 0.88 mGy. Conclusions: The results of the study concluded that by adjusting the applied tube voltage, kV, and tube current product time, mAs decreased the radiation dose to the chest X-ray by 58%.

THUDosePD:a three-dimensional Monte Carlo platform for phantom dose assessment

Monte Carlo simulations are frequently utilized in radiation dose assessments.However,many researchers find the prevailing computing platforms to be intricate.This highlights a pressing need for a specialized framework for phantom dose evalua-tion.To address this gap,we developed a user-friendly radiation dose assessment platform using the Monte Carlo toolkit,Geant4.The Tsinghua University Phantom Dose(THUDosePD)augments the flexibility of Monte Carlo simulations in dosi-metric research.Originating from THUDose,a code with generic,functional,and application layers,THUDosePD focuses predominantly on anatomical phantom dose assessment.Additionally,it enables medical exposure simulation,intricate geometry creation,and supports both three-dimensional radiation dose analysis and phantom format transformations.The system operates on a multi-threaded parallel CPU architecture,with some modules enhanced for GPU parallel computing.Benchmark tests on the ICRP reference male illustrated the capabilities of THUDosePD in phantom dose assessment,covering the effective dose,three-dimensional dose distribution,and three-dimensional organ dose.We also conducted a voxelization conversion on the polygon mesh phantom,demonstrating the method’s efficiency and consistency.Extended applications based on THUDosePD further underline its broad adaptability.This intuitive,three-dimensional platform stands out as a valuable tool for phantom radiation dosimetry research.

决策树支持下SmartDose在神经外科万古霉素个体化用药中的应用

目的评估Smart Dose个体化给药决策支持系统应用于我院神经外科万古霉素治疗药物的临床效用。方法收集2021年2月至10月在遵义市第一人医院神经外科住院并静脉使用万古霉素的患者作为研究对象,根据刘剑敏团队建立的万古霉素血药浓度解读决策树为基础,采用Smart Dose软件预测患者万古霉素谷浓度及临床使用剂量,分析谷浓度预测值与实测值之间的差异,并与未使用该软件预测谷浓度的患者进行统计分析比较,从而评价Smart Dose软件对万古霉素血药浓度的预测效能及辅助临床制定个体化给药方案的可行性。结果根据决策树标准筛选后,113例进行血药浓度分层解读。万古霉素血药浓度在5~<10 mg/L有33例(29.2%),达到治疗窗浓度10~20 mg/L的有62例(54.9%),>20 mg/L有18例(15.9%)。51例血药浓度采用Smart Dose软件辅助调整给药方案,38例被临床采纳并进行了万古霉素血药浓度复查。谷浓度预测准确率为100%;与未采纳调整方案的患者相比,具有较高的临床好转率(92.1%vs 53.9%,P<0.05)、较低的肾毒性发生率(0 vs 15.38%,P<0.05)、较短的用药疗程(14.3 d vs 19.6 d,P<0.05)及较少的药物治疗费用(3159.6元vs 5239.4元,P<0.05)。结论在决策树支持下并已获得万古霉素稳态谷浓度监测结果的基础上,SmartDose系统对万古霉素血药浓度具有较好的预测能力,可用于辅助临床制定万古霉素个体化给药方案。

Public Effective Dose Assessment Using Gross Alpha and Beta Radioactivity Levels of Tap Drinking Water in the District of Abidjan, Cote d’Ivoire

In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Beta counting system (Canberra iMaticTM) for analysis, the gross alpha and beta concentrations found varied from 0.001 ± 0.002 to 0.063 ± 0.050 Bq/l with an average of 0.013 ± 0.012 Bq/l and from 0.067 ± 0.080 to 0.320 ± 0.120 Bq/l with an average of 0.174 ± 0.076 Bq/l, respectively in samples. The public effective dose assessment showed values of dose to ingestion of alpha and beta emitter radionuclides lower than the recommended value of dose for drinking water 0.1 mSv/y, except in 30% of the samples. These results show the need for additional studies to be conducted in order to clarify the hazardousness of these water samples. However, this study still remains important because it has provided necessary data for future tap water quality monitoring studies in the District of Abidjan.

Dynamic modeling of total ionizing dose-induced threshold voltage shifts in MOS devices

The total ionizing dose(TID) effect is a key cause for the degradation/failure of semiconductor device performance under energetic-particle irradiation. We developed a dynamic model of mobile particles and defects by solving the rate equations and Poisson's equation simultaneously, to understand threshold voltage shifts induced by TID in silicon-based metal–oxide–semiconductor(MOS) devices. The calculated charged defect distribution and corresponding electric field under different TIDs are consistent with experiments. TID changes the electric field at the Si/SiO_(2) interface by inducing the accumulation of oxide charged defects nearby, thus shifting the threshold voltage accordingly. With increasing TID, the oxide charged defects increase to saturation, and the electric field increases following the universal 2/3 power law. Through analyzing the influence of TID on the interfacial electric field by different factors, we recommend that the radiation-hardened performance of devices can be improved by choosing a thin oxide layer with high permittivity and under high gate voltages.

Total Indicative Dose Determination in Water from the North Riviera Well Field of SODECI in Abidjan, Cote d’Ivoire

The Uranium-238 (238U), Thorium-232 (232Th) families and Potassium-40 (40K) are of terrestrial origin and contribute generally to an individual’s external exposure through our presence in this environment. They also contribute to the internal exposure through the ingestion of products and beverages such as water that are close to the earth. The aim of this work is to determine the committed effective dose or Total Indicative Dose (TID) due to gamma radioactivity of the borehole water from the Nord Riviera (NR) well field operated by the Côte d’Ivoire Water Distribution Company (SODECI) for the supply of drinking water to part of the population of Abidjan. In addition, the populations, with their habits, could use these borehole waters directly as drinking water. To this end, water samples from the seven (07) functional boreholes were collected and analyzed on a gamma spectrometry chain, equipped with an HPGe detector in the laboratory of the Radiation Protection Institute (RPI) of the GHANA Atomic Energy Commission (GAEC). The results of the specific activities of 238U, 232Th and 40K obtained were transcribed into TID. As the natural radioactivity of the borehole water is high [1], the TIDs calculated from the activity results of the natural radionuclides238U, 232Th, and 40K vary for the seven boreholes from 0.150 to 0.166 mSv/yr with an average of 0.161 ± 0.034 mSv/yr. The TID of the control tower, where the borehole water is mixed and treated for household use, is equal to 0.136 ± 0.03 mSv/yr. The TIDs obtained are therefore all slightly greater than the WHO reference dose value of 0.1 mSv/yr. But all remain below the UNSCEAR reference dose of 0.29 mSv/yr.

Evaluation of Entrance Skin Dose from Paediatric Diagnostic X-Ray Examination

As children are prone to be more radiosensitive than adults, it is imperative to assess the Entrance Skin Doses (ESDs) for patients being examined by X-rays, in order to ensure the optimization of dose while considering a number of other fickles. The ESD received by 50 paediatrics (aged 1-13 years) undergoing 8 types of X-ray examinations were measured at Federal Teaching Hospital, Ido-Ekiti, Ekiti, Nigeria, within a period of February 2019 to March 2020 using thermoluminescent dosimeters. The mean ± SD of ESDs were 0.85 ± 0.32, 2.04 ± 0.75, 0.60 ± 0.07, 0.62 ± 0.22, 0.57 ± 0.24, 1.75 ± 0.76, 0.93 ± 0.31 and 0.63 ± 0.06 mGy for Chest, Skull, Hand, Forearm, Knee, Abdomen, Leg and Feet, respectively. The mean ESDs were found to be within the recommended reference dose in all examinations, except for the Chest examination which was higher. The data obtained in this study will serve as existing data in Nigeria for future research works, as it would assist in optimizing dose to patients, especially the paediatrics.