Using beam profile inflection point in process of treatment planning system verification

BackgroundThe comparison between profiles during the commissioning of the treatment planning system is an essential procedure. It is impossible to designate a field size for off-axis, wedged, and FFF beams directly by using the definition of the on-axis symmetric field size. This work proposes the use of different characteristic points as indicators of the field size for commissioning and QA purposes. This work aimed to search for the beam profile’s characteristic points and use them for the TPS commissioning purposes.Materials and methodsThe proposal is to use profile inflection points as the beam profile characteristic points. The usage of dedicated software allowed for comparing distances between inflection points and between points of 50% intensity. For the off-axis, wedged, and FFF fields, comparisons were made to the nominal field sizes.ResultsDistances between inflection points proved to be different by less than 1 mm from nominal field sizes for all kinds of investigated beams.ConclusionsInflection points are convenient for comparing the off-axis, wedged, and FFF field sizes because of their independence from profile normalization. With finite accuracy, the inflection points could be used for the above kind of beam sizes designation.     

Assessment of skin dose in breast cancer radiotherapy: on-phantom measurement and Monte Carlo simulation

AimThe main purpose of the present study is assessment of skin dose in breast cancer radiotherapy.BackgroundAccurate assessment of skin dose in radiotherapy can provide useful information for clinical considerations.Materials and methodsA RANDO phantom was irradiated using a 6 MV Siemens Primus linac with medial and tangential radiotherapy fields for simulating breast cancer treatment. Dosimetry was also performed on various positions across the fields using an EBT3 radiochromic film. Similar conditions of measurement on the RANDO phantom including field size, irradiation angle, number of fields, etc. were subsequently simulated via the Monte Carlo N-Particle Transport code (MCNP). Ultimately, dose values for corresponding points from both methods were compared.ResultsConsidering dosimetry using radiochromic films on the RANDO phantom, there were points having underdose and overdose based on the prescribed dose and skin tolerance levels. In this respect, 81.25% and 18.75% of the points had underdose and overdose, respectively. In some cases, several differences were observed between the measurement and the MCNP simulation results associated with skin dose.ConclusionBased on the results of the points which had underdose, it was suggested that a bolus should be used for the given points. With regard to overdose points, it was advocated to consider skin tolerance dose in treatment planning. Differences between the measurement and the MCNP simulation results might be due to voxel size of tally cells in simulations, effect of beam’s angle of incidence, validation time of linac’s head, lack of electronic equilibrium in the build-up region, as well as MCNP tally type.     

Topological biology: A note on Rashevsky's transformation T.

In the bio-topological transformation between graphs denoted by (T ⁽¹⁾ X) N. Rashevsky (Bull. Math. Biophysics,18, 173–88, 1956) considers the number of fundamental sets which (a) have only one specialized point as source (and no other sources), (b) have no points in common (are “disjoined”); he proves that this number is an invariant of the transformation. In this note we show that Rashevsky's Theorem can be extended as follows:The number of fundamental sets of the first category is an invariant of the transformation. We must, however, count the subsidiary points of the transformed graph as specialized points. We recall that fundamental sets of the first category are those whose sources consist of specialized points only (Trucco,Bull. Math. Biophysics,18, 65–85, 1956). But in this modified version of the Theorem the fundamental sets may have more than one source and need not be disjoined.     

The Patient- And Nutrition-Derived Outcome Risk Assessment Score (PANDORA): Development of a Simple Predictive Risk Score for 30-Day In-Hospital Mortality Based on Demographics,Clinical Observation,and Nutrition

ObjectiveTo develop a simple scoring system to predict 30 day in-hospital mortality of in-patients excluding those from intensive care units based on easily obtainable demographic, disease and nutrition related patient data.MethodsScore development with general estimation equation methodology and model selection by P-value thresholding based on a cross-sectional sample of 52 risk indicators with 123 item classes collected with questionnaires and stored in an multilingual online database.SettingWorldwide prospective cross-sectional cohort with 30 day in-hospital mortality from the nutritionDay 2006-2009 and an external validation sample from 2012.ResultsWe included 43894 patients from 2480 units in 32 countries. 1631(3.72%) patients died within 30 days in hospital. The Patient- And Nutrition-Derived Outcome Risk Assessment (PANDORA) score predicts 30-day hospital mortality based on 7 indicators with 31 item classes on a scale from 0 to 75 points. The indicators are age (0 to 17 points), nutrient intake on nutritionDay (0 to 12 points), mobility (0 to 11 points), fluid status (0 to 10 points), BMI (0 to 9 points), cancer (9 points) and main patient group (0 to 7 points). An appropriate model fit has been achieved. The area under the receiver operating characteristic curve for mortality prediction was 0.82 in the development sample and 0.79 in the external validation sample.ConclusionsThe PANDORA score is a simple, robust scoring system for a general population of hospitalised patients to be used for risk stratification and benchmarking.     

Centiloid scale analysis for 18F-THK5351 PET imaging in Alzheimer’s disease

PurposeA standardized method for quantification is required for analyzing PET data, but such standards have not been established for tau PET imaging. The Centiloid scale has recently been proposed as a standard method for quantifying amyloid deposition on PET imaging. Therefore, the present study aimed to apply the Centiloid scale to ¹⁸F-THK5351 PET imaging in Alzheimer’s disease (AD).MethodsWe acquired ¹⁸F-THK5351 PET, ¹¹C-PiB PET, and MR images from 47 cognitively normal (CN) individuals and 28 patients with AD with mild to moderate dementia. PET images were spatially normalized to Montreal Neurological Institute space. The PET signals were then normalized using the signal in the reference volume of interest (VOI). Target VOI for specific ¹⁸F-THK5351 retention in AD was extracted by voxel-wise comparison of PET images between the 47 CN individuals and 16 AD patients with moderate dementia. Scale anchor points were defined by the CN individuals as 0-anchor points and by that of the average of the typical AD patients as 100-anchor points.ResultsSpecific retention of ¹⁸F-THK5351 was predominant in the angular gyrus, inferior temporal cortex, and parieto-occipital regions in patients with AD. Standardized uptake value ratio (SUVR) of 1.227 and 1.797 were defined as 0- and 100-anchor points, respectively. ¹⁸F-THK5351 PET data could be expressed using the Centiloid scale, with the SUVR of the ¹⁸F-THK5351 PET images converted to Centiloid using our VOI, the standard Centiloid reference VOI, and the following equation: Centiloid = 169.0 × SUVR–204.6.ConclusionCentiloid methods can be applied to tau PET imaging using ¹⁸F-THK5351.     

Exploring the nature of the H-bonds between the human class II MHC protein,HLA-DR1 (DRB*0101) and the influenza virus hemagglutinin peptide,HA306-318, using the quantum theory of atoms in molecules

The nature of the H-bonds between the human protein HLA-DR1 (DRB*0101) and the hemagglutinin peptide HA306-318 has been studied using the Quantum Theory of Atoms in Molecules for the first time. We have found four H-bond groups: one conventional CO··HN bond group and three nonconventional CO··HC, π··HC involving aromatic rings and HN··HC_aliphatic groups. The calculated electron density at the determined H-bond critical points suggests the follow protein pocket binding trend: P1 (2,311) >> P9 (1.109) > P4 (0.950) > P6 (0.553) > P7 (0.213) which agrees and reveal the nature of experimental findings, showing that P1 produces by a long way the strongest binding of the HLA-DR1 human protein molecule with the peptide backbone as consequence of the vast number of H-bonds in the P1 area and at the same time the largest specific binding of the peptide Tyr308 residue with aromatic residues located at the binding groove floor. The present results suggest the topological analysis of the electronic density as a valuable tool that allows a non-arbitrary partition of the pockets binding energy via the calculated electron density at the determined critical points.     

温中消疡汤对非甾体抗炎药相关性胃溃疡的疗效研究

摘要 目的：考察温中消疡汤对非甾体类抗炎药(Non-steroidal anti-inflammatory drugs，NSAIDs)相关性胃溃疡的临床疗效。方法：以80例2017年2月-2020年1月就诊于我院NSAIDs相关性胃溃疡患者为研究对象，采用随机数字表法分为研究组和对照组，每组40例。对照组患者进行口服雷贝拉唑治疗，研究组在对照组的基础上服用温中消疡汤。对中医证候疗效指标、中医证候积分和胃镜下疗效对治疗效果进行评价。结果：对两组患者中医证候疗效进行比较，研究组的总有效率为90.00 %，显著高于对照组的77.50 %(P＜0.05)。对治疗前后两组患者的中医证候（胃脘疼痛、腹胀、纳呆食少、反酸、嗳气、倦怠乏力、大便稀溏）积分进行比较，显示治疗前两组各证候积分及总积分无明显差异（P＞0.05）；经过治疗，两组患者各项证候积分及总积分均显著降低(P＜0.05)；与对照组相比，研究组胃脘疼痛、腹胀、纳呆食少、反酸及总积分均显著减低(P＜0.05)。对两组患者胃镜下黏膜改善情况进行比较，研究组的总有效率为97.50 %，显著高于对照组的87.50 %(P＜0.05)。结论：温中消疡汤治疗NSAIDs相关性胃溃疡，能显著提高对NSAIDs相关性胃溃疡的疗效，能更好的改善胃脘疼痛、腹胀、纳呆食少等症状，能明显促进胃黏膜的恢复。     

Is voice therapy an effective treatment for dysphonia? A randomised controlled trial

ObjectivesTo assess the overall efficacy of voice therapy for dysphonia.Design Single blind randomised controlled trial.Setting Outpatient clinic in a teaching hospital.Participants204 outpatients aged 17-87 with a primary symptom of persistent hoarseness for at least two months.Interventions After baseline assessments, patients were randomised to six weeks of either voice therapy or no treatment. Assessments were repeated at six weeks on the 145 (71%) patients who continued to this stage and at 12-14 weeks on the 133 (65%) patients who completed the study. The assessments at the three time points for the 70 patients who completed treatment and the 63 patients in the group given no treatment were compared.ResultsVoice therapy improved voice quality as assessed by rating by patients (P=0.001) and rating by observer (P<0.001). The treatment effects for these two outcomes were 4.1 (95% confidence interval 1.7 to 6.6) points and 0.82 (0.50 to 1.13) points. Amplitude perturbation showed improvement at six weeks (P=0.005) but not on completion of the study. Patients with dysphonia had appreciable psychological distress and lower quality of life than controls, but voice therapy had no significant impact on either of these variables.ConclusionVoice therapy is effective in improving voice quality as assessed by self rated and observer rated methods.

What is already known on this topic

Many patients with dysphonia are treated by voice therapyThe effectiveness of voice therapy in a diverse group of patients is unknown

What this study adds

Voice therapy is an effective treatment for dysphonia in terms of report by patients and perceptual ratings by an expertPsychological distress and reduction in general health status are common in patients with dysphonia but are not significantly affected by a course of voice therapy     

Machine Assisted Encoding Of Artifact Characteristics

Abstract

A computer encoding device known as a RAND Tablet can be applied in archeological researchto read off of an artifact, such as a flint projectile point, certain points of data that when used by a computer program to provide measurements from the artifact, can provide a basis for classification.     

乳腺良性肿块与乳腺癌患者的超声弹性成像对比

目的:对比乳腺良性肿块与乳腺癌患者的超声弹性成像,明确超声弹性成像的应用价值。方法:选取2014年5月-2016年1月我院乳腺肿块患者128人次共146例肿块,根据病理结果分为乳腺良性肿块和乳腺癌,比较超声弹性成像与病理结果。结果:128个患者共计肿块146例,99例结节为良性肿块,其中32例为乳腺纤维腺瘤,29例为乳腺增生结节,20例为乳腺脂肪瘤,6例为乳腺血管脂肪瘤,4例为乳腺导管腺瘤,8例为乳腺导管内乳头状瘤;47例肿块为恶性,其中37例肿块为浸润性导管癌,9例肿块为粘液腺癌,1例肿块为硬癌。乳腺良性肿块患者81人次共99例,其中1分43例(43.43%),2分34例(34.34%),3分18例(18.18%),4分4例(4.04%);乳腺癌患者47例,其中3分9例(19.15%),4分20例(42.55%),5分18例(38.30%)。超声弹性成像鉴别乳腺良性肿块与乳腺癌的灵敏度为95.96%,特异性为80.85%,准确度为91.10%,阴性预测值为90.48%,阳性预测值为91.35%。结论:超声弹性成像鉴别乳腺良性肿块与乳腺癌的灵敏度高达95.96%,具有较高准确度,可辅助诊断乳腺疾病。     

Contact-force monitoring increases accuracy of right ventricular voltage mapping avoiding “false scar” detection in patients with no evidence of structural heart disease

PurposeElectroanatomical mapping (EAM) could increase cardiac magnetic resonance imaging (CMR) sensitivity in detecting ventricular scar. Possible bias may be scar over-estimation due to inadequate tissue contact. Aim of the study is to evaluate contact-force monitoring influence during EAM, in patients with idiopathic right ventricular arrhythmias.Methods20 pts (13 M; 43 ± 12 y) with idiopathic right ventricular outflow tract (RVOT) arrhythmias and no structural abnormalities were submitted to Smarttouch catheter Carto3 EAM. Native maps included points collected without considering contact-force. EAM scar was defined as area ≥1 cm² including at least 3 adjacent points with signal amplitude (bipolar <0.5 mV, unipolar 3,5 mV), surrounded by low-voltage border zone. EAM were re-evaluated offline, removing points collected with contact force <5 g. Finally, contact force-corrected maps were compared to the native ones.ResultsAn EAM was created for each patient (345 ± 85 points). After removing poor contact points, a mean of 149 ± 60 points was collected. The percentage of false scar, collected during contact force blinded mapping compared to total volume, was 6.0 ± 5.2% for bipolar scar and 7.1 ± 5.9% for unipolar scar, respectively. No EAM scar was present after poor contact points removal. Right ventricular areas analysis revealed a greater number of points with contact force < 5 g acquired in free wall, where reduced mean bipolar and unipolar voltage were recorded.ConclusionsTo date this is the first work conducted on structurally normal hearts in which contact-force significantly increases EAM accuracy, avoiding “false scar” related to non-adequate contact between catheter and tissue.     

Eterofillia E Relativa Morfologia in Centaurea Horrida Bad

Summary

The Author points out as the Centaurea horrida Bad., an endemic thorny plant of Sardinia, presents a manifested eterophillia and tries to explain why, among the different Authors, only Moris has evidenced the characteristic; he refers some personal morphological observations on the species and concludes with a new summarized diagnosis of it.     

Automatic Classification: Projectile Points from West Texas

Abstract

Stepwise discriminant function can be used for automatic classification of points. The classification is based on six measurements and can serve as an efficient aid to the typologist.     

贝伐单抗联合替莫唑胺对老年胶质母细胞瘤术后患者预后的影响

目的:探讨贝伐单抗联合替莫唑胺对老年胶质母细胞瘤术后患者预后的影响。方法:选择2014年1月到2016年1月在第四军医大学西京医院诊治的老年胶质母细胞瘤术后患者78例,根据治疗方法的不同分为观察组与对照组各39例,观察组给予替莫唑胺与贝伐单抗联合治疗,对照组只给予替莫唑胺治疗,观察和比较两组患者的的预后情况。结果:观察组与对照组的有效率分别为48.7%和23.1%,观察组显著高于对照组(P0.05)。观察组治疗期间的肝肾反应、胃肠道反应、疲乏、骨髓抑制等毒副反应的发生率明显低于对照组(P0.05)。观察组治疗后的KPS与ECOG评分分别为64.22±2.19分和1.65±0.45分,对照组为56.35±4.50分和2.41±0.51分,组间对比差异明显(P0.05),且与治疗前对比也有明显差异(P0.05)。观察组与对照组的的中位生存时间分别为30个月和21个月,观察组的3年生存率为41.0%,对照组为16.4%,观察组都明显优于对照组(P0.05)。结论:贝伐单抗联合替莫唑胺可显著改善老年胶质母细胞瘤术后患者的生存质量,提高治疗疗效与延长患者的生存时间,且安全性较高。     

The LabBM score is an excellent survival prediction tool in patients undergoing palliative radiotherapy

Background and aimThe prognostic assessment of patients referred for palliative radiotherapy can be conducted by site-specific scores. A quick assessment that would cover the whole spectrum could simplify the working day of clinicians who are not specialists for a particular disease site. This study evaluated a promising score, the LabBM (validated for brain metastases), in patients treated for other indications.Materials and methodsThe LabBM score was calculated in 375 patients by assigning 1 point each for C-reactive protein and lactate dehydrogenase above the upper limit of normal, and 0.5 points each for hemoglobin, platelets and albumin below the lower limit of normal. Uni- and multivariate analyses were performed.ResultsMedian overall survival gradually decreased with increasing point sum (range 25.1–1.1 months). When grouped according to the original three-tiered model, excellent discrimination was found. Patients with 0–1 points had a median survival of 15.7 months. Those with 1.5–2 points had a median survival of 5.8 months. Finally, those with 2.5–3.5 points had a median survival of 3.2 months (all p-values ≤ 0.001).ConclusionThe LabBM score, which is derived from inexpensive blood tests and easy to use, stratified patients into three very distinct prognostic groups and deserves further validation.     

Mental Health Following Acquisition of Disability in Adulthood—The Impact of Wealth

BackgroundAcquisition of a disability in adulthood has been associated with a reduction in mental health. We tested the hypothesis that low wealth prior to disability acquisition is associated with a greater deterioration in mental health than for people with high wealth.MethodsWe assess whether level of wealth prior to disability acquisition modifies this association using 12 waves of data (2001–2012) from the Household, Income and Labour Dynamics in Australia survey–a population-based cohort study of working-age Australians. Eligible participants reported at least two consecutive waves of disability preceded by at least two consecutive waves without disability (1977 participants, 13,518 observations). Fixed-effects linear regression was conducted with a product term between wealth prior to disability (in tertiles) and disability acquisition with the mental health component score of the SF–36 as the outcome.ResultsIn models adjusted for time-varying confounders, there was evidence of negative effect measure modification by prior wealth of the association between disability acquisition and mental health (interaction term for lowest wealth tertile: -2.2 points, 95% CI -3.1 points, -1.2, p<0.001); low wealth was associated with a greater decline in mental health following disability acquisition (-3.3 points, 95% CI -4.0, -2.5) than high wealth (-1.1 points, 95% CI -1.7, -0.5).ConclusionThe findings suggest that low wealth prior to disability acquisition in adulthood results in a greater deterioration in mental health than among those with high wealth.     

Habitat preferences of the Syrian Woodpecker Dendrocopos syriacus in urban environments: an ambiguous effect of pollution

Capsule The occurrence of the Syrian Woodpecker Dendrocopos syriacus in an urbanized habitat is determined by the number of trees and pollutant emissions. Air pollution may weaken trees and increase the number of insects inhabiting them.

Aims To determine the habitat preferences of the Syrian Woodpecker in the highly urbanized environment of the city of Kraków.

Methods A set of 13 habitat and environmental parameters of 50 breeding territories and 50 random points were evaluated. A logistic regression was used to determine the probability of species occurrence, and Akaike's information criterion was used for model selection.

Results The number of trees, coverage of woody vegetation, total vegetation cover and level of pollutant emissions were significantly higher in Syrian Woodpecker breeding territories than in the random points. The model best explaining the probability of species occurrence consisted of four parameters: the number of trees, coverage of the total built-up area, total vegetation cover and pollutant emissions. The parameters best explaining a high probability of species occurrence were high number of trees and high pollutant emissions.

Conclusion Air pollution may weaken trees and potentially increase the number of insects inhabiting them, an important component of the Syrian Woodpecker's diet. However, the negative impact of air pollution on birds may impact on their condition. Urban habitats could, therefore, act as an ecological trap for this species.     

Rummells-Maske: A Clovis Find-Spot in Iowa

Abstract

The first controlled excavation of a Clovis site in Iowa revealed a concentration of complete and fragmentary Clovis Fluted projectile points. The site, in eastern Iowa, is interpreted as a projectile point cache destroyed by agricultural implements. Measurements and photographs are provided to facilitate the comparison of the collection with assemblages from other states.     

基于数据包络分析的三级医院适宜规模研究

目的 研究三级医院床位和人员的适宜规模,控制医院过度发展和资源浪费。方法 以北京市三级医院为研究样本,确定投入-产出指标,利用DEAP（2.1）软件,分析1991—2011年北京市三级医院规模报酬状态,找出规模报酬拐点,从而确定三级医院适宜规模。结果 2011年,41所医院中,有39家医院处于DEA有效状态,2家医院处于DEA非有效状态;时间序列纵向分析中,有18家医院出现规模报酬拐点。北京市三级综合医院的适宜规模的严格控制标准为：床位606张,95%CI：(425,786),在职职工1 219人,95%CI：(797,1 641);较宽松的控制标准为：床位1 058张,95%CI：(831,1 284),在职职工2 236人,95%CI：(1 716,2 757)。结论 研究得到了三级公立医院的规模控制标准,要严格控制公立医院的规模和特大型医院的数量,注重提高医院的运行效率,缩短平均住院日。