scholarly journals The impact of different simulation modalities on target volume delineation in breast-conserving radiotherapy

2020 ◽  
Author(s):  
Meng Jin ◽  
Xia Liu ◽  
Jiabin Ma ◽  
Xiansong Sun ◽  
Hongnan Zhen ◽  
...  
Keyword(s):  
Ct Images ◽  
Conformity Index ◽  
Mr Images ◽  
Mean Values ◽  
Surgical Clips ◽  
Tumor Bed ◽  
Volume Delineation ◽  
Ct Simulation ◽  
The Mean ◽  
The Impact

Abstract Background In the management of breast-conserving radiotherapy, computed tomography (CT) simulation is now commonly used to identify tumor bed while has difficult ies defining precisely. We aimed to evaluate the impact of magnetic resonance (MR) and CT simulation on defining the postoperative tumor bed for breast-conserving radiotherapy in patients without the aid of surgical clips. Methods From August 2018 to March 2019, twenty patients with T 1 - 2 N 0 M 0 breast cancer at our situation were enrolled. All the patients underwent breast-conserving surgery without implantation of surgical clips and were prepared to receive radiotherapy. CT and MR images were acquired on the same day for each patient. Three radiation oncologists independently assigned cavity visualization score (CVS) and delineated the tumor bed based on first the CT then the MR images with a 14-day interval for each patient. Interobserver variability was assessed by volumes, generalized conformity index (CI gen ) and the distance between the centers of mass (dCOM). Differences in mean values for parameters were tested by paired t -test or one-way analysis of variance, as appropriate. Results The median age of the enrolled patients was 48 years old. First, the mean volumes of tumor bed derived from MR were 22%, 27% and 21% smaller than those based on CT images for each observer. Second, the mean CI gen was significantly superior, and dCOM was smaller for MR than for CT images (CI gen : 0.59 vs 0.52, P = 0.008; dCOM: 1.30 cm vs 1.39 cm, P = 0.095). Third, the mean CVS was 3.23±1.34 and 2.43±0.92 for MR and CT images, respectively ( P = 0.035). In the subgroup with a CT-based CVS≥3, the mean dCOM obtained from CT was larger than that from the MR images (1.35 cm vs 1.19 cm, P = 0.048). Last, there was a positive association between the CVS and CI gen for both modalities (CT: r = 0.699, P = 0.001; MR: r = 0.895, P ＜ 0.001). Conclusion Compared to CT, MR can improve the visualization of changes in the postoperative tumor bed. In addition, MR can yield a more precise definition of the tumor bed and improve the consistency of tumor bed contouring in patients without surgical clips.

scholarly journals Biases in CloudSat Falling Snow Estimates Resulting from Daylight-Only Operations

2021 ◽  
Vol 13 (11) ◽  
pp. 2041
Author(s):  
Lisa Milani ◽  
Norman B. Wood
Keyword(s):  
Water Cycle ◽  
Mean Values ◽  
The Mean ◽  
Satellite Missions ◽  
The Impact ◽  
Global Mean

Falling snow is a key component of the Earth’s water cycle, and space-based observations provide the best current capability to evaluate it globally. The Cloud Profiling Radar (CPR) on board CloudSat is sensitive to snowfall, and other satellite missions and climatological models have used snowfall properties measured by it for evaluating and comparing against their snowfall products. Since a battery anomaly in 2011, the CPR has operated in a Daylight-Only Operations (DO-Op) mode, in which it makes measurements primarily during only the daylit portion of its orbit. This work provides estimates of biases inherent in global snowfall amounts derived from CPR measurements due to this shift to DO-Op mode. We use CloudSat’s snowfall measurements during its Full Operations (Full-Op) period prior to the battery anomaly to evaluate the impact of the DO-Op mode sampling. For multi-year global mean values, the snowfall fraction during DO-Op changes by −10.16% and the mean snowfall rate changes by −8.21% compared with Full-Op. These changes are driven by the changes in sampling in DO-Op and are very little influenced by changes in meteorology between the Full-Op and DO-Op periods. The results highlight the need to sample consistently with the CloudSat observations or to adjust snowfall estimates derived from CloudSat when using DO-Op data to evaluate other precipitation products.

​Impact of Extreme Hot Environmental Temperature Period on Marker Enzymes of Carbohydrate Metabolism in Non-descript Sheep from Arid Tracts of Rajasthan

2021 ◽  
Author(s):  
Anandita Srivastava ◽  
Nalini Kataria
Keyword(s):  
Carbohydrate Metabolism ◽  
Environmental Temperature ◽  
Age Groups ◽  
Extreme Temperature ◽  
Mean Value ◽  
Marker Enzymes ◽  
Mean Values ◽  
The Mean ◽  
The Impact ◽  
Enzymes Of Carbohydrate Metabolism

Background: The present investigation was envisaged to find out the impact of extreme hot environmental temperature period (ETP) on marker enzymes of carbohydrate metabolism in male and female non-descript sheep of various age groups i.e. 4 to 13 months from arid tracts of Rajasthan. Glucose-6-phosphate dehydrogenase (G-6-PDH) and malate dehydrogenase (MDH) marker enzymes of carbohydrate metabolism were considered for study. Methods: During the period October 2016-June 2017 blood samples were collected to harvest sera for spectrophotometric method from 240 healthy animals selected from private slaughter house during moderate and extreme hot environmental temperature periods (ETPs). The mean values of markers attained during moderate ETP were reckoned as the control. It was 10.00 ± 0.10 UL-1 and 42.00±1.00 respectively. Conclusion: The mean value of MDH was significantly (p≤0.05) higher while G-6-PDH significantly (p≤0.05) lowers during extreme hot temperature in comparison to moderate period. Therefore, it could be concluded that variations in enzyme markers were associated with changes in environmental temperatures. Probably ETP were able to produce a profound effect on carbohydrate metabolism in sheep. Therfore it can be suggested that during the period of extreme temperature balanced ration must be provided to the animal along with proper management to decrease the severity of temperature impact.

scholarly journals Records of performance and sanitary status from a dairy cattle herd in southern Brazil

2011 ◽  
Vol 31 (1) ◽  
pp. 01-09 ◽  
Author(s):  
Cláudio E. F. Cruz ◽  
Djeison L. Raymundo ◽  
Cristine Cerva ◽  
Saulo P. Pavarini ◽  
André G. C. Dalto ◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Reproductive Performance ◽  
Cattle Herd ◽  
Lactation Period ◽  
Mean Values ◽  
Cattle Diseases ◽  
Dairy Cattle Herd ◽  
The Mean ◽  
The Impact ◽  
Voluntary Waiting Period

Over the last decades, the emphasis on the health of dairy cows has changed from an individual to a herd level. In this scenario, the role played by the recording system and its interpretation by veterinarians has gained primordial importance. The records of productive and reproductive performance and of sanitary status from a southern Brazilian dairy cattle herd have been presented and discussed. The period of study was 2000-2009. Mean values per lactation period were 349D 8436M 290F 275P 201SCS (D: days in lactation, M: kg of milk yield, F: kg of fat, P: kg of protein and SCS: somatic cell score in 1000 cells/ml of milk). Major indexes of reproductive efficiency included age at first calving (31 months), services per conception (2.1), intercalving interval (428 days), calving to conception interval (146 days), mean annual rates of parturitions (76.2%), fetal losses (9.8-19.0%), and stillbirths (3.6%), apart of voluntary waiting period (94 days). Main information on sanitary status of the herd was associated with the mean prevalence of common disorders of dairy cattle such as anaplasmosis (29.8%), mastitis (27.8%), digital diseases (26.3%), ovarian cysts (21.3%), placental retention (19.7%), postpartum uterine infections (10.6%), and calf diarrhea (23.7%) and pneumonia (16.8%), among others. In addition, culling reasons (low reproductive performance [56.3%] and udder/mastitis problems [33.6%]), causes of cattle deaths (anaplasmosis [16.4%] and leukosis [11.4]), and the impact of cattle diseases such as tuberculosis, leukosis, and neosporosis on the herd have also been presented and succinctly discussed. Numbers between brackets represent rates accumulated in the 10-year period.

scholarly journals Ultrasound-based examination of the medial ligament complex shows gender- and age-related differences in laxity

2020 ◽  
Author(s):  
Patricia M. Lutz ◽  
Matthias J. Feucht ◽  
Judith Wechselberger ◽  
Michael Rasper ◽  
Wolf Petersen ◽  
...  
Keyword(s):  
Knee Joint ◽  
Knee Flexion ◽  
Joint Space ◽  
Medial Knee ◽  
Mean Values ◽  
Age Related ◽  
Gender And Age ◽  
Joint Width ◽  
The Mean ◽  
The Impact

Abstract Purpose Ultrasound (US) examination of the medial joint space of the knee has played a subordinate diagnostic role up till now. The purpose of the present study was to describe mean values of medial joint width and to investigate the impact of gender, age, and body mass index (BMI) on medial joint laxity in healthy knees using modern, dynamic US in a standardized fashion in unloaded and standardized loaded conditions. Methods A total of 65 subjects with 79 healthy knees were enrolled in this study. All volunteers underwent clinical examination of the knee. The medial knee joint width was determined using US in a supine position at 0° and 30° of knee flexion in unloaded and standardized loaded (= 15 Dekanewton, daN) conditions using a specific device. Mean values were described and correlations between medial knee joint width and gender, age, and BMI were assessed. Results Thirty-two females and 33 males were enrolled in this study. The mean medial joint width in 0° unloaded was 5.7 ± 1.2 mm and 7.4 ± 1.4 mm loaded. In 30° of knee flexion, the mean medial joint width was 6.1 ± 1.1 mm unloaded and 7.8 ± 1.2 mm loaded. The average change between unloaded and loaded conditions in 0° was 1.7 ± 1.0 mm and in 30° 1.7 ± 0.9 mm. A significant difference between genders was evident for medial joint width in 0° and 30° of flexion in unloaded and loaded conditions (p < 0.05). With rising age, a significant increased change of medial joint space width between unloaded and loaded conditions could be demonstrated in 0° (p = 0.032). No significant correlation between BMI and medial joint width in US could be found. Conclusion Mean values of medial joint width in unloaded and standardized loaded conditions using a fixation device could be demonstrated. Based on the results of this study, medial knee joint width in US is gender- and age-related in healthy knees. These present data may be useful for evaluating patients with acute or chronic pathologies to the medial side of the knee. Level of evidence III.

Discordant GH and IGF-1 Results in Treated Acromegaly: Impact of GH Cutoffs and Mean Values Assessment

2020 ◽  
Author(s):  
Claudia Campana ◽  
Francesco Cocchiara ◽  
Giuliana Corica ◽  
Federica Nista ◽  
Marica Arvigo ◽  
...  
Keyword(s):  
Characteristic Curve ◽  
Area Under The Curve ◽  
Receiver Operator Characteristic Curve ◽  
Mean Values ◽  
Pituitary Diseases ◽  
Discordance Rate ◽  
Values Assessment ◽  
The Mean ◽  
The Impact

Abstract Context Discordant growth hormone (GH) and insulin-like growth factor-1 (IGF-1) values are frequent in acromegaly. Objective To evaluate the impact of different GH cutoffs on discordance rate. To investigate whether the mean of consecutive GH measurements impacts discordance rate when matched to the last available IGF-1 value. Design Retrospective study. Setting Referral center for pituitary diseases. Patients Ninety acromegaly patients with at least 3 consecutive evaluations for GH and IGF-1 using the same assay in the same laboratory (median follow-up 13 years). Interventions Multimodal treatment of acromegaly. Main Outcome Measures Single fasting GH (GHf) and IGF-1 (IGF-1f). Mean of 3 GH measurements (GHm), collected during consecutive routine patients’ evaluations. Results At last evaluation GHf values were 1.99 ± 2.79 µg/L and age-adjusted IGF-1f was 0.86 ± 0.44 × upper limit of normality (mean ± SD). The discordance rate using GHf was 52.2% (cutoff 1 µg/L) and 35.6% (cutoff 2.5 µg/L) (P = 0.025). “High GH” discordance was more common for GHf &lt;1.0 µg/L, while “high IGF-1” was predominant for GHf &lt;2.5 µg/L (P &lt; 0.0001). Using GHm mitigated the impact of GH cutoffs on discordance (GHm &lt;1.0 µg/L: 43.3%; GHm &lt;2.5 µg/L: 38.9%; P = 0.265). At receiver-operator characteristic curve (ROC) analysis, both GHf and GHm were poor predictors of IGF-1f normalization (area under the curve [AUC] = 0.611 and AUC = 0.645, respectively). The prevalence of disease-related comorbidities did not significantly differ between controlled, discordant, and active disease patients. Discussion GH/IGF-1 discordance strongly depends on GH cutoffs. The use of GHm lessen the impact of GH cutoffs. Measurement of fasting GH levels (both GHf and GHm) is a poor predictor of IGF-1f normalization in our cohort.

scholarly journals Analysis of a Discrete-Time Queueing Model with Disasters

Mathematics ◽  
2021 ◽  
Vol 9 (24) ◽  
pp. 3283
Author(s):  
Mustafa Demircioglu ◽  
Herwig Bruneel ◽  
Sabine Wittevrongel
Keyword(s):  
Discrete Time ◽  
Queueing System ◽  
Time Slot ◽  
Probability Distributions ◽  
Single Server ◽  
Bernoulli Process ◽  
Tail Probabilities ◽  
Mean Values ◽  
The Mean ◽  
The Impact

Queueing models with disasters can be used to evaluate the impact of a breakdown or a system reset in a service facility. In this paper, we consider a discrete-time single-server queueing system with general independent arrivals and general independent service times and we study the effect of the occurrence of disasters on the queueing behavior. Disasters occur independently from time slot to time slot according to a Bernoulli process and result in the simultaneous removal of all customers from the queueing system. General probability distributions are allowed for both the number of customer arrivals during a slot and the length of the service time of a customer (expressed in slots). Using a two-dimensional Markovian state description of the system, we obtain expressions for the probability, generating functions, the mean values, variances and tail probabilities of both the system content and the sojourn time of an arbitrary customer under a first-come-first-served policy. The customer loss probability due to a disaster occurrence is derived as well. Some numerical illustrations are given.

scholarly journals Evaluation of the Impact of Magnetic Resonance Imaging (MRI) on Gross Tumor Volume (GTV) Definition for Radiation Treatment Planning (RTP) of Inoperable High Grade Gliomas (HGGs)

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Omer Sager ◽  
Ferrat Dincoglan ◽  
Selcuk Demiral ◽  
Hakan Gamsiz ◽  
Bora Uysal ◽  
...  
Keyword(s):  
Gross Tumor Volume ◽  
Tumor Volume ◽  
Radiation Treatment ◽  
Resonance Imaging ◽  
Mr Images ◽  
Radiation Treatment Planning ◽  
Target Definition ◽  
Ct Simulation ◽  
Magnetic Resonance Imaging Mri ◽  
The Impact

Aim and Background. Inoperable high-grade gliomas (HGGs) comprise a specific group of brain tumors portending a very poor prognosis. In the absence of surgical management, radiation therapy (RT) offers the primary local treatment modality for inoperable HGGs. Optimal target definition for radiation treatment planning (RTP) of HGGs is a difficult task given the diffusely infiltrative nature of the disease. In this context, detailed multimodality imaging information may add to the accuracy of target definition in HGGs. We evaluated the impact of Magnetic Resonance Imaging (MRI) on Gross Tumor Volume (GTV) definition for RTP of inoperable HGGs in this study. Materials and Methods. Twenty-five inoperable patients with a clinical diagnosis of HGG were included in the study. GTV definition was based on Computed Tomography- (CT-) simulation images only or both CT-simulation and MR images, and a comparative assessment was performed to investigate the incorporation of MRI into RTP of HGGs. Results. Median volume of GTV acquired by using CT-simulation images only and by use of CT and MR images was 65.3 (39.6-94.3) cc and 76.1 (46.8-108.9) cc, respectively. Incorporation of MRI into GTV definition has resulted in a median increase of 12.61% (6%-19%) in the volume of GTV defined by using the CT-simulation images only, which was statistically significant (p < 0.05). Conclusion. Incorporation of MRI into RTP of inoperable HGGs may improve GTV definition and may have implications for dose escalation/intensification strategies despite the need for further supporting evidence.

Photometric results of the long-term monitoring of the active asteroid (596) Scheila

2020 ◽  
Author(s):  
Zhong-Yi Lin ◽  
Chen-Yen Hsu
Keyword(s):  
Light Curve ◽  
Rotation Period ◽  
Impact Event ◽  
Mean Values ◽  
Photometric Observations ◽  
The Mean ◽  
The Difference ◽  
The Impact ◽  
Term Monitoring

&lt;p&gt;(596) Scheila was observed to have an active appearance as a result of impact event in late 2010. In additional the coma feature, the shape of light curve had been found the difference probably fresh material or surface properties changed around the impact site. In this study, we present the results of our monitoring observations obtained in 2014 and 2019-2020. The mean values of the color indices (B&amp;#8722;V&amp;#160;= (0.75 &amp;#177; 0.08)&lt;sup&gt;m&lt;/sup&gt;,&amp;#160;V&amp;#8722;R&amp;#160;= (0.45 &amp;#177; 0.04)&lt;sup&gt;m&lt;/sup&gt;, and&amp;#160;R&amp;#8722;I&amp;#160;= (0.44 &amp;#177; 0.09)&lt;sup&gt;m&lt;/sup&gt;) agree well with the values for asteroids of the D-types. The rotation period of the asteroid estimated from photometric observations in 2014 is 15.8 &amp;#177; 0.1 h.&amp;#160;The shape of the light curve is similar as that found after impact event. Furthermore, we did not find any rotational color variability in B-V, V-R and R-I diagrams, meaning the observed surface in this observing period of 2019-2020 is homogeneous.&lt;/p&gt;

Different Patellar Indices and Their Role in Decision-Making: An MRI-Based Study

2020 ◽  
Author(s):  
Sivashanmugam Raju ◽  
Karthikeyan Chinnakkannu ◽  
Balasubramanian Balakumar ◽  
Ramanivas Sundareyan ◽  
Saravanakumar P. Kaliappan ◽  
...  
Keyword(s):  
Decision Making ◽  
Patellofemoral Pain ◽  
Mr Images ◽  
Strong Negative Correlation ◽  
Mean Values ◽  
Patellar Position ◽  
Asymptomatic Patients ◽  
The Mean ◽  
Magnetic Resonance Imaging Mri ◽  
The Many

AbstractMagnetic resonance imaging (MRI) of knee has become the integral part of knee evaluation, hence any MRI based study adds more value if it helps in the decision-making process, especially for surgery in treating patellofemoral pain. We tried to determine normal patellar indices using knee MR images and the correlation between them and also compared the results with different ethnic population. We analyzed the prospectively collected MR images of 117 knees/patients, and Insall–Salvati (IS) index, modified IS index, patellotrochlear (PT) index, and patellophyseal (PP) index were calculated. Two standard deviations from the mean were used to define the normal and abnormal patellar position. Cohen's kappa values were used to assess the agreement between the indices and the correlation between them was analyzed using Pearson's correlation. The mean values for IS index, modified IS index, PT index, and PP index were 1.00, 1.53, 0.40, and 0.58, respectively. There was very good agreement between PT index and PP index. There was weak correlation between all the indices except the one between PT and PP indices which had a strong negative correlation. Based on commonly used methodology, there were 4% of asymptomatic patients who were outside the standardized cut-off values and different indices classified different knees as abnormal. This indicates patellar position should be one among the many other factors, not as a sole factor when making a surgical decision in patellofemoral pain. We also noted that the indices compared fairly with other populations. Further research is needed to determine the clinical applicability of these indices.

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