bluuebunny/crossref_metadata_2025 huggingface dataset:
Medical specialties and life expectancy: An analysis of doctors’ obituaries 1997–2019
Authors: Brayne Adam B. , Brayne Ralph P. , Fowler Alexander J.
Published: February 2021

Background

Previous studies have found emergency medicine physicians have a reduced life expectancy compared to other doctors, using small subsets of data from the obituary section of the British Medical Journal. Technological advances now allow the entire catalogue of obituaries to be interrogated, which allows exploration of the relationship between medical specialty, age at death and cause of death in doctors.

Methods

Publicly available electronic records were obtained by web scraping and analysed with natural language processing algorithms. Obituaries published in the British Medical Journal between January 1997 and August 2019 were scraped and analysed for differences in age and cause of death and also relative survival analysis compared to the general U.K. population.

Results

Data were extracted from 8156 obituaries. The specialties with the oldest average age at death were general practitioners (80.3, SD = 12.5, n = 2508), surgeons (79.9, SD = 13.6, n = 853) and pathologists (79.8, SD = 13.8, n = 394). The specialties with the youngest average age at death were emergency physicians (58.7, SD = 23.6, n = 43), anaesthetists (75.5, SD = 16.1, n = 473) and radiologists (75.8, SD = 14.5, n = 172). Cancer was the most common cause of death and did not differ by specialty. Doctors on average have an older age at death than the general U.K. population.

Conclusions

A doctor's specialty has a significant association with their age at death, with general practitioners living the longest and emergency physicians the shortest, with proportionately more accidental deaths. Likely due to its recency as a separate specialty, the emergency physician group is the smallest, which may censor and falsely reduce this group's age at death. The observed increased life expectancy and the reduced cardiovascular disease in this cohort may be associated with lifestyle and socioeconomic factors.
Laser plume containment during flexible transnasal laryngoscopy
Authors: Hoffman Henry T. , Walsh Jarrett E. , Pratt Alessandra , Miller Robert M. , Schwalje Adam , Stegall Helen R. , Nonnenmann Matt
Published: February 2021

Objective

To evaluate a negative pressure microenvironment designed to contain laser plume during flexible transnasal laryngoscopy.

Methods

The Negative Pressure Face Shield (NPFS) was previously reported as well tolerated with initial use on 30 patients. Diagnostic transnasal laryngoscopy was performed on an additional 108 consecutive patients who were evaluated by questionnaires and sequential pulse oximetry. Further study addressed operative transnasal potassium‐titanyl‐phosphate (KTP) laser laryngoscopy with biopsy done on four patients employing the NPFS.

Results

The previously described NPFS version 3 (v.3), a transparent acrylic barrier with two anterior instrumentation ports, was modified by repositioning the side suction port closer to the level of the nose and deepening the lateral sides, squaring off the lower projection. A post‐procedure questionnaire employing a 5‐point Likert scale ranging from no symptoms (rating of 1) to intolerable (rating of 5) identified excellent patient tolerance of the new design (v.4), among 22 patients evaluated and similar in the comparison to the 116 patients using version 3. Among the 138 patients analyzed, only one patient rated the experience as greater than “mild claustrophobia.” 100% of patients answered either “none” or “mild” to the pain and shortness of breath questions. The NPFS (v.4) was then successfully used in four patients for laser laryngoscopy with biopsy of laryngeal papilloma (3/4) and hemorrhagic polyp (1/4). Post‐procedure questionnaire identified no shortness of breath (4/4), no claustrophobia (4/4), no pain (4/4) and no significant changes in pulse oximetry during use.

Conclusion

Extensive experience in performing diagnostic laryngoscopy with the NPFS directed design changes leading to successful use for transnasal flexible laser laryngoscopy with biopsy in a negative pressure microenvironment.

Level of Evidence

Level 2b (Cohort Study).
Production of C6–C14 Medium‐Chain Fatty Acids in Seeds and Leaves via Overexpression of Single Hotdog‐Fold Acyl‐Lipid Thioesterases
Authors: Kalinger Rebecca S. , Williams Danielle , Ahmadi Pirshahid Ali , Pulsifer Ian P. , Rowland Owen
Published: February 2021

ACYL‐LIPID THIOESTERASES (ALT) are a type of plant acyl–acyl carrier protein thioesterase that generate a wide range of medium‐chain fatty acids and methylketone (MK) precursors when expressed heterologously in Escherichia coli. While this makes ALT‐type thioesterases attractive as metabolic engineering targets to increase production of high‐value medium‐chain fatty acids and MKs in plant systems, the behavior of ALT enzymes in planta was not well understood before this study. To profile the substrate specificities of ALT‐type thioesterases in different plant tissue types, AtALT1‐4 from Arabidopsis thaliana, which have widely varied chain length and oxidation state preferences in E. coli, were overexpressed in Arabidopsis seeds, Camelina sativa seeds, and Nicotiana benthamiana leaves. Seed‐specific overexpression of ALT enzymes led to medium‐chain fatty acid accumulation in Arabidopsis and Camelina seed triacylglycerols, and transient overexpression in N. benthamiana demonstrated that the substrate preferences of ALT‐type thioesterases in planta generally agree with those previously determined in E. coli. AtALT1 and AtALT4 overexpression in leaves and seeds resulted in the accumulation of 12–14 carbon‐length fatty acids and 6–8 carbon‐length fatty acids, respectively. While it was difficult to completely profile the products of ALT‐type thioesterases that generate MK precursors (i.e. β‐keto fatty acids), our results nonetheless demonstrate that ALT enzymes are catalytically diverse in planta. The knowledge gained from this study is a significant step towards being able to use ALT‐type thioesterases as metabolic engineering tools to modify the fatty acid profiles of oilseed crops, other plants, and microorganisms.
Understanding the Temperature‐Responsive Self‐Assemblies of Amphiphilic Random Copolymers by SANS in D2O Solution
Authors: Domenici Fabio , Guazzelli Elisa , Masotti Elena , Mahmoudi Najet , Gabrielli Sara , Telling Mark T. F. , Martinelli Elisa , Galli Giancarlo , Paradossi Gaio
Published: February 2021

The self‐assembly behavior, in aqueous solution, of amphiphilic methacrylic random copolymers with perfluoroalkyl and polyoxyethylene side chains and the morphology of the resulting nanostructures are investigated by small‐angle neutron scattering (SANS). The results allow to clarify the effect of temperature on the self‐assembly features of copolymers and the structural morphology of both unimer single‐chain entities and larger multi‐chain aggregates of unimers. Shape, flexibility, and size of the aggregates are proved to be modulated by temperature and copolymer composition. The existence of three distinct phases of self‐assembled structures is pointed out as a function of increasing temperature: 1) globular unimers; 2) coexistence of extended unimers and aggregates; and 3) aggregates, which overall show full reversibility in a wide range of copolymer concentrations.
Temperature and pH Responsive Light‐Harvesting System Based on AIE‐Active Microgel for Cell Imaging
Authors: Fan Xiaotong , Teng Choon Peng , Yeo Jayven Chee Chuan , Li Zibiao , Wang Tingting , Chen Haiming , Jiang Lu , Hou Xunan , He Chaobin , Liu Junqiu
Published: February 2021

A highly emissive microgel is synthesized by polymerizing tetraphenylethene (TPE) based comonomers, acrylic acid, NIPAM, and permanent crosslinker ethylenebisacrylamide (BIS) (named as TPE microgel), which exhibited temperature responsive fluorescence emission. Rhodamine B (RhB), a positively charged molecule, is then inserted onto the surface of fabricated microgels through electrostatic interaction. As a result, a novel artificial light harvesting system with high energy transfer efficiency is constructed (named as TPE microgel‐RhB light harvesting system), which is the first light harvesting system based on TPE microgels presenting dual response to pH and temperature. MTT assay indicates the fabricated TPE microgel and TPE microgel‐RhB light harvesting system has good cytocompatibility. The strong fluorescence and good cytocompatibility make them perfect candidates for cell imaging. The prepared emissive microgel and light‐harvesting system with desirable fluorescent property not only provide a new strategy for the fabrication of tunable luminescent nanomaterials, but also expand potential applications in the fields of stomach recognition, temperature sensors, and drug delivery.
Laser‐Induced NanoKneading (LINK): Deformation of Patterned Azopolymer Nanopillar Arrays via Photo‐Fluidization
Authors: Ho Jhih‐Hao , Shih Tsung‐Wei , Liu Chih‐Ting , He Hung‐Chieh , Lin Yu‐Liang , Lee Lin‐Ruei , Lin Kuan‐Ting , Tseng Yu‐Hsuan , Sugiyama Teruki , Chen Jiun‐Tai
Published: February 2021

Ordered arrays of polymer nanostructures have been widely investigated because of their promising applications such as solar‐cell devices, sensors, and supercapacitors. It remains a great challenge, however, to manipulate the shapes of individual nanostructures in arrays for tailoring specific properties. In this study, an effective strategy to prepare anisotropic polymer nanopillar arrays via photo‐fluidization is presented. Azobenzene‐containing polymers (azopolymers) are first infiltrated into the nanopores of ordered anodic aluminum oxide (AAO) templates. After the removal of the AAO templates using weak bases, azopolymer nanopillar arrays can be prepared. Upon exposure of linearly polarized lights, azobenzene groups in the azopolymers undergo trans–cis–trans photoisomerization, causing mass migration and elongation of the nanopillar along with the polarization directions. As a result, anisotropic nanopillar arrays can be fabricated, of which the deformation degrees are controlled by the illumination times. Furthermore, patterned nanopillar arrays can also be constructed with designed photomasks. This work presents a practical and versatile strategy to fabricate arrays of anisotropic nanostructures for future technical applications.
Controllable Radical Polymerization of Selenide Functionalized Vinyl Monomers and Its Application in Redox Responsive Photonic Crystals
Authors: Liu Shaoxiang , Li Qilong , Li Yingying , Zhang Jiandong , Pan Xiangqiang , Zhu Jian , Zhu Xiulin
Published: February 2021

Selenium‐containing monomer (p‐phenylseleno) styrene (p‐PhSeSt) is polymerized by reversible addition‐fragmentation chain transfer polymerization. Polymer, (P(p‐PhSeSt)), with controlled molecular weight and narrow molecular weight is obtained. The selenide moiety in obtained P(p‐PhSeSt) can be selectively oxidized to selenoxide or selenone groups by H2O2 or NaClO, respectively. These oxidized groups can be further reduced to selenide by Na2S2O4. The structure changing of polymers during such redox cycle is characterized by nuclear magnetic resonance, X‐ray photoelectron spectroscopy, and size exclusion chromatography. Properties, such as thermal performance, glass transition temperature, water contact angles, and refractive indices, of the resulting polymers are systematically investigated before and after oxidation. In addition, SiO2 inverse opal photonic crystal (IOPC) is fabricated by sacrificial polymer colloidal template method. Owing to changes of the RIs of P(p‐PhSeSt) after selective oxidation, the predictable change of PC bandgap as a redox‐responsive PC sensor is successfully realized, which provides new perspectives for modulating photonic crystals.
MCPIP1 expression positively correlates with melanoma‐specific survival of patients, and its overexpression affects vital intracellular pathways of human melanoma cells
Authors: Nowak Iwona , Brożyna Anna A. , Zabłocka Marzena , Student Sebastian , Durbas Małgorzata , Bugara Beata , Rokita Hanna
Published: February 2021

The suppressive activity of monocyte chemoattractant protein 1‐induced protein 1 (MCPIP1) an inflammation‐related ribonuclease, has been described in a few cancer types but has yet to be assessed in the most common subtype of skin cancer: melanoma. Here, we have evaluated the MCPIP1 expression in melanoma tissues by reanalysis of publicly available transcriptome data from 89 melanoma samples, and immunohistochemical staining of 21 primary and 81 metastatic melanomas. Our data implicated decreased MCPIP1 expression in melanoma tumors compared to normal tissues, and positive correlation between high ribonuclease expression and melanoma‐specific survival of patients. To investigate the ribonuclease activity in melanoma cells, MCPIP1 was ectopically expressed in the MV3 human melanoma cell line. Following the transcriptome, proteome, and intracellular signaling of MCPIP1‐overexpressing MV3 cells was assessed via real‐time quantitative polymerase chain reaction, Western blot analysis, and RNAseq. MV3 cells overexpressing MCPIP1 exhibited a broad range of alterations in the transcriptome and proteome, as well as in the phosphorylation status of a number of proteins, strongly indicating MCPIP1‐dependent cell cycle arrest and inhibition of Akt/mTOR signaling in these cells. Moreover, we have shown, that MCPIP1 overexpression downregulates miRNA‐193a‐3p expression in MV3 cells. Furthermore, the majority of the described effects were dependent on the ribonucleolytic activity of the protein. The presented body of data strongly suggests a potential tumor suppressor role and possible future application as a positive prognostic marker of MCPIP1 protein in melanoma.
Anchoring bias in the evaluation of basketball players: A closer look at NBA draft decision‐making
Authors: Berger Tobias , Daumann Frank
Published: February 2021

The NBA installed the draft mechanism to fairly distribute young amateur players among its franchises. As this policy hinges on appropriate talent evaluation skills of the respective organizations, it can be considered a proxy for decision‐making under uncertainty. Such judgments are prone to fallacies and systemic mistakes. The article found the RSCI rank as a problematic metric, which is the source for systematic draft errors. It can be shown that in many cases, managers do not deviate enough from the pre‐draft rankings of players, leading to systematically over‐ and undervaluing certain groups of talents. This can be described as a decision‐quality‐lowering anchoring bias.
Body Mass Index Is Significantly Associated With Disease Severity in Spinocerebellar Ataxia Type 2 Patients
Authors: Almaguer‐Mederos Luis E. , Pérez‐Ávila Ilbedis , Aguilera‐Rodríguez Raúl , Velázquez‐Garcés Maria , Almaguer‐Gotay Dennis , Hechavarría‐Pupo Ricardo , Rodríguez‐Estupiñán Annelié , Auburger Georg
Published: February 2021

Background

Spinocerebellar ataxia type 2 is a progressive neurodegenerative disorder due to an unstable expansion of a CAG repeat in the ATXN2 gene. Although weight loss has been associated with disease progression in several neurodegenerative conditions, it has been barely assessed in patients with spinocerebellar ataxia type 2.

Objective

The objective of this study was to test whether body mass index is altered in patients with spinocerebellar ataxia type 2 with varying expansion sizes from early to late disease stages.

Methods

A cross‐sectional case–control study was performed, which included 222 clinically and molecularly diagnosed patients and 214 sex‐ and age‐matched healthy individuals. ATXN2 genotypes and sex were considered as risk factors. Clinical outcomes included the body mass index, age at onset, disease duration, Scale for the Assessment and Rating of Ataxia score, disease stage, dysphagia, and progression rate. Multiple linear regression models were generated.

Results

Body mass index was significantly decreased in male patients, but not in female patients, relative to control subjects. In addition to sex, body mass index was significantly associated with age at onset and progression rate. Conversely, body mass index, along with repeat length in ATXN2 expanded alleles and disease duration, was associated with Scale for the Assessment and Rating of Ataxia score. In addition, body mass index, along with the age at onset and the repeat length in ATXN2 normal and expanded alleles, has a significant influence on progression rate.

Conclusions

Body mass index might be a useful biomarker of disease severity, particularly in male patients with spinocerebellar ataxia type 2 in the context of nutritional interventions or clinical trials assessing the efficacy of promising new drugs. © 2021 International Parkinson and Movement Disorder Society
Compound hemizygous variants in SERPINA7 gene cause thyroxine‐binding globulin deficiency
Authors: Fang Yanlan , Chen Hong , Chen Qingqing , Wang Chunlin , Liang Li
Published: February 2021

Sub‐heading

Compound hemizygous variants in SERPINA7 gene.

Background

Thyroxine‐binding globulin (TBG) is encoded by SERPINA7 (OMIM. 314200) which is located on Xq22.3. SERPINA7 variants caused TBG deficiency which does not require treatment, but the decreased thyroxine may be misdiagnosed as hypothyroidism. We discovered some variants of TBG caused by alterations that differ from previously reported.

Materials and Methods

In this study, we enrolled 32 subjects from 10 families and sequenced the SERPINA7 genes of TBG‐deficient subjects. Then, variants were analyzed to assess their effect on TBG expression and secretion. Bioinformatics database, protein structure, and dynamics simulation were used to evaluate the deleterious effects. Finally, we identified 2 novel and 4 known variants, and found 26 of 30 subjects carried the p.L303F. The DynaMut predictions indicated the variants (p.E91K, p.I92T, p.R294C, and p.L303F) exhibited decreased stability.

Conclusion

Analyses revealed the p.L303F change the protein stability and flexibility, and it had an impact on the function of TBG, but when coexisted with other variants it might change the conformational structure of the protein and aggravate the damage to the protein. We speculated that the existence of a higher number of variants resulted in lower TBG secretion.
A study on fractional COVID‐19 disease model by using Hermite wavelets
Authors: Kumar Sunil , Kumar Ranbir , Momani Shaher , Hadid Samir
Published: February 2021

The preeminent target of present study is to reveal the speed characteristic of ongoing outbreak COVID‐19 due to novel coronavirus. On January 2020, the novel coronavirus infection (COVID‐19) detected in India, and the total statistic of cases continuously increased to 7 128 268 cases including 109 285 deceases to October 2020, where 860 601 cases are active in India. In this study, we use the Hermite wavelets basis in order to solve the COVID‐19 model with time‐ arbitrary Caputo derivative. The discussed framework is based upon Hermite wavelets. The operational matrix incorporated with the collocation scheme is used in order to transform arbitrary‐order problem into algebraic equations. The corrector scheme is also used for solving the COVID‐19 model for distinct value of arbitrary order. Also, authors have investigated the various behaviors of the arbitrary‐order COVID‐19 system and procured developments are matched with exiting developments by various techniques. The various illustrations of susceptible, exposed, infected, and recovered individuals are given for its behaviors at the various value of fractional order. In addition, the proposed model has been also supported by some numerical simulations and wavelet‐based results.
Identifying initial value problem for time‐fractional diffusion equation with Caputo‐like counterpart hyper‐Bessel operator: Optimal error bound analysis and regularization method
Authors: Yang Fan , Sun Qiao‐Xi , Li Xiao‐Xiao
Published: February 2021

In this paper, we consider the inverse problem for identifying the initial value problem for time‐fractional diffusion equation with hyper‐Bessel operator. Firstly, we show that this problem is ill‐posed and analyze the optimal error bound. Next, we use the fractional Landweber iterative regularization method to solve this problem and give the error estimates between the regularization solution and the exact solution under the a priori regularization parameter choice rule and a posteriori regularization parameter choice rule. Finally, we use numerical examples to verify the effectiveness of this method.
Applying homotopy perturbation method to provide an analytical solution for Newtonian fluid flow on a porous flat plate
Authors: Ghanbari Ashrafi Tareq , Hoseinzadeh Siamak , Sohani Ali , Shahverdian Mohammad Hassan
Published: February 2021

This research work is going to apply the homotopy perturbation method to solve the problem of flowing Newtonian fluid on a flat plate. For this purpose, initially, the problem, including the governing equations and boundary conditions, is defined, and after that, the considered assumptions to solve the defined problem are introduced. Next, the working principle of the homotopy perturbation method is described, and then, the way to obtain the analytical solution using the homotopy perturbation method is presented, and finally, the accuracy of the proposed analytical solution in comparison to the numerical approach is compared for validation. Both momentum and energy equations are solved. The maple software program is utilized for carrying out the mathematical calculations, while the validation is done using the profiles for stream function, velocity distribution, stress, and dimensionless temperature as the key indicators related to the solution. The conducted comparison shows that the analytical solution provided by the homotopy perturbation method is able to predict all the important performance criteria for the problem very well, and therefore, the homotopy perturbation method has a strong potential to be employed for providing the analytical solution for such problems.
Pullback dynamics for the 3‐D incompressible Navier–Stokes equations with damping and delay
Authors: Cui Xiaona , Shi Wei , Li Xuezhi , Yang Xin‐Guang
Published: February 2021

This paper is concerned with the tempered pullback dynamics of the 3‐D nonautonomous incompressible Navier–Stokes equations with nonlinear damping and delay in a bounded domain. Basing on some delicate priori estimates, the existence and uniqueness of weak and strong solutions have been proved. Then under some appropriate hypotheses on the external forces, we show the existence of the minimal family of pullback attractors with respect to fixed and generic universes.
Equivalence between viscosity and weak solutions for the parabolic equations with nonstandard growth
Authors: Fang Yuzhou , Zhang Chao
Published: February 2021

We consider the link between weak and viscosity solutions of the parabolic equations with nonstandard growth

where 1 < p ≤ q1 ≤ q2 ≤ … ≤ qk < ∞ and f satisfies some given assumptions. More precisely, we aim to establish that bounded viscosity solutions and bounded weak solutions with continuity coincide.
Oscillatory solutions of fractional integro‐differential equations II
Authors: Restrepo Joel E. , Suragan Durvudkhan
Published: February 2021

We establish necessary conditions to obtain oscillatory solutions for some classes of the Prahbakar‐type and Atangana–Baleanu fractional integro‐differential operators. Illustrative examples are also given. The obtained results extend the previous developments in the field from our recent paper.
N‐soft mappings with application in medical diagnosis
Authors: Demir İzzettin
Published: February 2021

Fatimah et al. suggested different complement operations for N‐soft sets. However, these operations do not comply with De Morgan's laws and double complementation law for N‐soft sets. So we do not restate some classical theorems on topological spaces in the realm of N‐soft sets. Besides, the mappings are a basic mathematical tool which is utilized in numerous areas of mathematics, other sciences, and their applications. But there is not any note on the mappings in the setting of N‐soft set theory. To deal with these problems, firstly, we advance the concept of complement of an N‐soft set and demonstrate that De Morgan's laws and double complementation law are satisfied in N‐soft set theory according to this new definition. Then we present an idea of the N‐soft mappings and investigate some of their properties. Also, we illustrate given properties with examples and counter examples. Finally, using the N‐soft mappings, we describe a mathematical system design for diagnosing purpose of the Covid‐19 disease.
Study of fractional order impulsive evolution problem under nonlocal Cauchy conditions
Authors: Shah Kamal , Ullah Atta , Nieto Juan J.
Published: February 2021

In this research article, we discuss the important class of impulsive evolution problem of fractional order subject to nonlocal Cauchy condition. We studied the aforesaid problem via the use of coincidence degree theory of topology. The respective results are devoted to existence theory of solution. To support our main work, we also give some test problems.
Evaluation of scatter rejection and correction performance of 2D antiscatter grids in cone beam computed tomography
Authors: Park Yeonok , Alexeev Timur , Miller Brian , Miften Moyed , Altunbas Cem
Published: February 2021

Purpose

We have been investigating two‐dimensional (2D) antiscatter grids (2D ASGs) to reduce scatter fluence and improve image quality in cone beam computed tomography (CBCT). In this work, two different aspects of 2D ASGs, their scatter rejection and correction capability, were investigated in CBCT experiments. To correct residual scatter transmitted through the 2D ASG, it was used as a scatter measurement device with a novel method: grid‐based scatter sampling.

Methods

Three focused 2D ASG prototypes with grid ratios of 8, 12, and 16 were developed for linac‐mounted offset detector CBCT geometry. In the first phase, 2D ASGs were used as a scatter rejection device, and the effect of grid ratio on CT number accuracy and contrast‐to‐noise ratio (CNR) evaluated in CBCT images. In the second phase, a grid‐based scatter sampling method which exploits the signal modulation characteristics of the 2D ASG’s septal shadows to measure and correct residual scatter transmitted through the grid was implemented. To evaluate CT number accuracy, the percent change in CT numbers was measured by changing the phantom from head to pelvis size and configuration.

Results

When 2D ASG was used as a scatter rejection device, CT number accuracy increased and the CT number variation due to change in phantom dimensions was reduced from 23% to 2–6%. A grid ratio of 16 yielded the lowest CT number variation. All three 2D ASGs yielded improvement in CNR, up to a factor of two in pelvis‐sized phantoms. When 2D ASG prototypes were used for both scatter rejection and correction, CT number variations were reduced further, to 1.3–2.6%. In comparisons with a clinical CBCT system and a high‐performance radiographic ASG, 2D ASG provided higher CT number accuracy under the same imaging conditions.

Conclusions

When 2D ASG is used solely as a scatter rejection device, substantial improvement in CT number accuracy can be achieved by increasing the grid ratio. Two‐dimensional ASGs also provided significant CNR improvement even at lower grid ratios. Two‐dimensional ASGs used in conjunction with the grid‐based scatter sampling method provided further improvement in CT number accuracy, irrespective of the grid ratio, while preserving 2D ASGs’ capacity to improve CNR. The combined effect of scatter rejection and residual scatter correction by 2D ASG may accelerate implementation of new techniques in CBCT that require high quantitative accuracy, such as radiotherapy dose calculation and dual energy CBCT.
Automatic segmentation of hippocampus in hippocampal sparing whole brain radiotherapy: A multitask edge‐aware learning
Authors: Qiu Qingtao , Yang Ziduo , Wu Shuyu , Qian Dongdong , Wei Jun , Gong Guanzhong , Wang Lizhen , Yin Yong
Published: February 2021

Purpose

This study aimed to improve the accuracy of the hippocampus segmentation through multitask edge‐aware learning.

Method

We developed a multitask framework for computerized hippocampus segmentation. We used three‐dimensional (3D) U‐net as our backbone model with two training objectives: (a) to minimize the difference between the targeted binary mask and the model prediction; and (b) to optimize an auxiliary edge‐prediction task which is designed to guide the model detection of the weak boundary of the hippocampus in model optimization. To balance the multiple task objectives, we proposed an improved gradient normalization by adaptively adjusting the weight of losses from different tasks. A total of 247 T1‐weighted MRIs including 131 without contrast and 116 with contrast were collected from 247 patients to train and validate the proposed method. Segmentation was quantitatively evaluated with the dice coefficient (Dice), Hausdorff distance (HD), and average Hausdorff distance (AVD). The 3D U‐net was used for baseline comparison. We used a Wilcoxon signed‐rank test to compare repeated measurements (Dice, HD, and AVD) by different segmentations.

Results

Through fivefold cross‐validation, our multitask edge‐aware learning achieved Dice of 0.8483 ± 0.0036, HD of 7.5706 ± 1.2330 mm, and AVD of 0.1522 ± 0.0165 mm, respectively. Conversely, the baseline results were 0.8340 ± 0.0072, 10.4631 ± 2.3736 mm, and 0.1884 ± 0.0286 mm, respectively. With a Wilcoxon signed‐rank test, we found that the differences between our method and the baseline were statistically significant (P < 0.05).

Conclusion

Our results demonstrated the efficiency of multitask edge‐aware learning in hippocampus segmentation for hippocampal sparing whole‐brain radiotherapy. The proposed framework may also be useful for other low‐contrast small organ segmentations on medical imaging modalities.
Temperature‐based MRI safety simulations with a limited number of tissues
Authors: Carluccio Giuseppe , Akgun Can , Vaughan John Thomas , Collins Christopher
Published: February 2021

Purpose

Demonstrate ability to produce reasonable simulations of temperature using numerical models of the human body with a limited number of tissues.

Methods

For both a male and female human body model, numerical simulations were used to calculate temperature distributions in three different models of the same human body: the original model with 35 tissues for the male model and 76 tissues for the female model, a simplified model having only three tissues (muscle, fat, and lung), and a simplified model having six tissues (muscle, fat, lung, bone, brain, and skin).

Results

Although a three‐tissue model gave reasonable specific absorption rate estimates in comparison to an original with many more tissues, because of tissue‐specific thermal and physiological properties that do not affect specific absorption rate, such as rate of perfusion by blood, the three‐tissue model did not provide temperature distributions similar to those of the original model. Inclusion of a few additional tissues, as in the six‐tissue model, produced results in much better agreement with those from the original model.

Conclusion

Reasonable estimates of temperature can be simulated with a limited number of tissues, although this number is higher than the number of tissues required to produce reasonable simulations of specific absorption rate. For exposures primarily in the head and thorax, six tissues may be adequate for reasonable estimates of temperature.
Sodiation mechanism via reversible surface film formation on metal oxides for sodium‐ion batteries
Authors: Portenkirchner Engelbert , Rommel Sebastian , Szabados Lukas , Griesser Christoph , Werner Daniel , Stock David , Kunze‐Liebhäuser Julia
Published: February 2021

Long term galvanostatic charge/discharge cycling of oxygen deficient, carburized and self‐organized titanium dioxide (TiO2) nanotubes (NTs) in sodium ion (Na) batteries (SIBs) are subject to a significant self‐improving charge storage behavior. Surface reactions upon sodiation of carburized NTs form acicular surface films that can be reversibly cycled. We show that, alongside organic species from the decomposition of the electrolyte, mainly inorganic compounds, such as Na2O2 and Na2CO3, are the main constituents. These components possess a characteristic acicular morphology. Na2O2 is found to form upon sodiation and converted to NaO2 upon desodiation. This, in combination with its pseudo‐capacitive charge storage characteristics, explains the excellent rate capability measured for TiO2‐x‐C NTs. The observed high reversibility of this surface chemistry is also essential for the fast kinetics and the high capacity retention found in the system. Our findings point to a more general Na‐ion storage mechanism, that is potentially relevant to other transition metal oxides also.
Dynamics of consumption inequality among occupational groups in India: Evidence from National Sample Survey data
Authors: Yazir Palathingal , Kumar Anoop S.
Published: February 2021

This study analyses the dynamics of consumption inequality among various occupational groups using household survey data from National Sample Survey (NSS). Three rounds of NSS data namely, the 50th (1993–1994), 61st (2004–2005), and 66th (2009–2010) were taken for the purpose of analysis. Various measures such as Gini coefficient, overlapping index, and raking matrices are estimated for the whole as well as the subgroups using ANOGI methodology. From the analysis, it is found that the level of overall inequality as well as the between‐group inequality is on the rise during the period of analysis. Further, the measures such as relative overlap index and ranking matrices give conclusive evidence that the difference between various groups in terms of consumption expenditure pattern is increasing over time. From the ranking matrices, it is seen that the last six groups, constituting households with occupation in the unorganized sector and low level organized workers falls below the 30th percentile of consumption expenditure distribution of the first group groups that consists of individuals holding to technical, administrative, managerial, and executive occupations. Worsening inequality across various occupational groups is a matter of concern, especially from the policy perspective. As economic growth without equitable distribution of income is not a desirable outcome.
Preparation of flame retardant and conductive epoxy resin composites by incorporating functionalized multi‐walled carbon nanotubes and graphite sheets
Authors: Zhang Sheng , Jiang Yichong , Sun Yongyuan , Sun Jun , Xu Bo , Li Hongfei , Gu Xiaoyu
Published: February 2021

This work reports our recent efforts on the preparation of functionalized multi‐walled carbon nanotubes (f‐CNTs) and its application in improving the fire, conductive, and mechanical performance of epoxy resin (EP) composites in combination with graphite sheets (GSs). The addition of hybrid carbon nanomaterials can effectively improve the mechanical properties of epoxy. Consequently, when the mass fraction of f‐CNTs/GSs is 3.9 wt%, the limiting oxygen index (LOI) value is increased to 27.4%, and the tensile strength and notched impact strength of epoxy are increased by 33.5% and 44.8%, respectively. Increasing the content of carbon nanomaterials can further improve the flame retardancy and electrical conductivity of EP composites. For the sample containing 11.0 wt% f‐CNTs/GSs, the electrical conductivity is further increased to 1.7 × 10−3 S/cm, which can be regarded as conductive materials. The LOI value is reached to 28.6%, with peak heat release and total heat release reduced by 26.4% and 16.4%, respectively.
Synergistically enhanced ultraviolet aging resistance and interfacial adhesion of poly (p‐phenylene benzobisoxazole) fiber with soluble naphthalimide sizing
Authors: Lu Kangyi , Ge Xin , Wei Zhenhai , Li Gang , Yang Xiaoping , Liu Hanyang
Published: February 2021

Amino‐terminated naphthalimide (NDI) with ultraviolet (UV) absorptivity was synthesized to sizing on poly(p‐phenylene benzobisoxazole) (PBO) fiber surface, and UV aging resistance PBO fiber and interfacial adhesion of their composites was investigated. Compared with pristine PBO fiber, the surface chemical activity and roughness of NDI‐PBO fiber were increased. In comparison with pristine PBO fiber, tensile strength, intrinsic viscosity ([η]), and diameter of NDI‐PBO fiber showed a better retention, and the enhanced UV‐aging resistance was verified by hardly visible macroscopic defects on NDI‐PBO fiber. Meanwhile, transverse fiber bundle test strength of NDI‐PBO fiber composites was promoted by stronger mechanical interlocking and chemical interaction. The synergistic improvement in UV aging resistance and interfacial adhesion of PBO fiber was attributed to undamaged crystal and molecular structure from UV protection effects of NDI layer and strong chemical bonding between reactive groups of NDI and epoxy matrix.
Creating community: Expanding access to psychosocial programs for Latina breast cancer survivors
Authors: Buki Lydia P. , Schwartz Jessica R. , McInerney Elizabeth E. W.
Published: February 2021

Objective

Breast cancer survivors often derive benefits from psychosocial interventions, but less is known about Latina women's experiences. Given the disproportionately high disease burden faced by Latina survivors, it is critical to examine ways to enhance access for this population. Thus, the present study aimed to (a) examine women's perceptions of factors associated with effective delivery of a psychosocial program designed for Spanish speaking women with limited access to care, and (b) identify the mechanisms by which the program enhanced women's psychological well‐being.

Methods

In a qualitative study, in‐depth interviews were conducted with 15 immigrant Latina breast cancer survivors who previously received psychosocial services at a community‐based organization. Grounded theory was used to analyze the data.

Results

Through open, axial, and selective coding, we arrived at the core category achieving a sense of community. The psychosocial program promoted access and enhanced women's psychological well‐being by creating a sense of community among participants. This was facilitated by three primary aspects of service provision: access factors, a holistic approach to health, and therapeutic factors imparted through a biweekly support group.

Conclusions

Psychosocial services promoted a sense of community among Latina breast cancer survivors while reflecting their cultural values and unique psychosocial needs. Findings may guide the development of interventions to increase access to care, enhance health outcomes, and create and maintain a sense of community among medically underserved populations.
How enzymes harness highly unfavorable proton transfer reactions
Authors: Silverstein Todd P.
Published: February 2021

Acid–base reactions that are exceedingly unfavorable under standard conditions can be catalytically important at enzyme active sites. For example, in triose phosphate isomerase, a glutamate side chain (nominal pKa ≈ 4 in solution) can in fact deprotonate a CH group that is vicinal to a carbonyl (pKa ≈ 18 in solution). This is true because of three distinct interactions: (a) ground state pKa shifts due to environment polarity and electrostatics; (b) dramatic increases in effective molarity due to optimization of proximity and orientation; and (c) transition state pKa shifts due to binding interactions and the formation of strong low barrier hydrogen bonds. In this report, we review the literature showing that the sum of these three effects supplies more than enough free energy to push forward proton transfer reactions that under standard conditions are exceedingly nonspontaneous and slow.
The interaction of p38 with its upstream kinase MKK6
Authors: Kumar Ganesan Senthil , Page Rebecca , Peti Wolfgang
Published: February 2021

Mitogen‐activated protein kinase (MAPK; p38, ERK, and JNK) cascades are evolutionarily conserved signaling pathways that regulate the cellular response to a variety of extracellular stimuli, such as growth factors and interleukins. The MAPK p38 is activated by its specific upstream MAPK kinases, MKK6 and MKK3. However, a comprehensive molecular understanding of how these cognate upstream kinases bind and activate p38 is still missing. Here, we combine NMR spectroscopy and isothermal titration calorimetry to define the binding interface between full‐length MKK6 and p38. It was shown that p38 engages MKK6 not only via its hydrophobic docking groove, but also influences helix αF, a secondary structural element that plays a key role in organizing the kinase core. It was also shown that, unlike MAPK phosphatases, the p38 conserved docking (CD) site is much less affected by MKK6 binding. Finally, it was demonstrated that these interactions with p38 are conserved independent of the MKK6 activation state. Together, the results revealed differences between specificity markers of p38 regulation by upstream kinases, which do not effectively engage the CD site, and downstream phosphatases, which require the CD site for productive binding.
Concomitant inpatient prescribing of strong opioids with sedatives: Associations with comorbid conditions
Authors: Li Ray J. , Caughey Gillian E. , Shakib Sepehr
Published: February 2021

Co‐prescribing of opioids and sedatives is a known risk factor for opioid‐induced ventilatory impairment (OIVI). Prevalence data for sedative and opioid co‐prescription in inpatients in Australia are unknown. Our objective was to determine the prevalence of inpatient sedative and opioid co‐prescribing and to identify factors associated with co‐prescription. We conducted a retrospective cross‐sectional study from July 2017 to October 2017 across four South Australian hospitals utilizing a centralized electronic health record. Multivariate analysis was used to identify characteristics predictive of co‐prescribing of a strong opioid (fentanyl, hydromorphone, morphine, and oxycodone) and sedative medications (benzodiazepines, antiepileptics, antipsychotics, and tricyclic antidepressants). Of the 6170 inpatients, 2795 (45.3%) were prescribed a strong opioid and of those, 1889 (30.6% of all inpatients) were co‐prescribed a sedative. Of those prescribed a strong opioid, five (0.18%) developed OIVI. Patients prescribed a strong opioid had a 27–77% increased likelihood of being prescribed a sedative. Factors predictive of sedative co‐prescribing included the presence of disease of the central nervous system adjusted OR (aOR) 8.66 [95% CI 5.83–12.9] and respiratory disease aOR 1.42 [95% CI 1.17–1.72]. Nearly, one third of all hospital inpatients were co‐prescribed a strong opioid and a sedative medication. Patients with comorbidities resulting in increased risk of respiratory depression/OIVI were more likely to have sedative co‐prescription. Clinicians should be aware of the effects of high‐risk medications and ensure that systems and monitoring are in place that help mitigate adverse outcomes.
A Mechanistic In Vivo/Ex Vivo Pharmacokinetic‐Pharmacodynamic Model of Tenofovir for HIV Prevention
Authors: Jayachandran Priya , Garcia-Cremades Maria , Vučićević Katarina , Bumpus Namandjé N. , Anton Peter , Hendrix Craig , Savić Radojka
Published: February 2021

Defining tissue and plasma‐specific prophylactic drug concentrations is central to pre‐exposure prophylaxis product development for sexual transmission of HIV‐1. Pharmacokinetic (PK) data from study RMP‐02/MTN‐006 comparing single dose oral tenofovir disoproxil fumarate with single and multiple dose rectal tenofovir (TFV) gel administration in HIV‐1 seronegative adults was used to construct a multicompartment plasma‐rectal tissue population PK model for TFV and tenofovir‐diphosphate (TFVdp) in plasma and rectal tissue. PK data were collected in five matrices: TFV (plasma, rectal tissue homogenate), TFVdp (peripheral blood mononuclear cells, rectal mononuclear cells (MMCs), rectal tissue homogenate). A viral growth compartment and a delayed effect compartment for p24 antigen expression measured from an ex vivo explant assay described HIV‐1 infection and replication. Using a linear PK/pharmacodynamic model, MMC TFVdp levels over 9,000 fmol/million cells in the explant assay provided apparent viral replication suppression down to 1%. Parameters were estimated using NONMEM version 7.4.
CAD/CAM‐based referencing aids to reduce preoperative radiation exposure for intraoperative navigation
Authors: Zeller Alexander‐Nicolai , Zimmerer Rüdiger M. , Springhetti Sina , Tavassol Frank , Rahlf Björn , Neuhaus Michael‐Tobias , Gellrich Nils‐Claudius
Published: February 2021

Background

All intraoperative navigation systems need a referencing procedure prior to utilization, usually requiring an additional computed tomography (CT) or cone beam computed tomograph (CBCT) scan. As new techniques in the field of Computer‐aided design / Computer‐aided manufacturing (CAD/CAM) have evolved, it seemed favourable to develop a new referencing method not relying on additional CT or CBCT scans.

Methods

A digital maxillary dental scan was used to create a referencing splint by CAD/CAM containing four reference points. By matching scanned dental model and initial trauma‐CT, the splints position and thus the reference points were digitally simulated. These splints data were imported into the navigation system in Standard Tessellation Language (STL) format. These data were also 3D printed and the resulting piece was placed on the anatomical models' teeth. The methods accuracy was then assessed in vitro.

Conclusion

Our method for referencing of intraoperative navigation can be feasible to avoid an additional CT or CBCT prior to navigation.
Ranking graphs through hitting times of Markov chains
Authors: De Santis Emilio
Published: February 2021

In the present paper we show that for any given digraph , that is, an oriented graph without self‐loops and 2‐cycles, one can construct a 1‐dependent Markov chain and n identically distributed hitting times T1, … , Tn on this chain such that the probability of the event Ti > Tj, for any i, j = 1, … , n, is larger than if and only if . This result is related to various paradoxes in probability theory, concerning in particular non‐transitive dice.
Voluntary disclosure of greenhouse gas emissions by cities under carbon disclosure project: A sustainable development approach
Authors: Chen Fuzhong , Hussain Muzzammil , Khan Jawad Ahmad , Mir Ghulam Mustafa , Khan Zeeshan
Published: February 2021

Today's world is facing a serious challenge of high carbon emissions. A large number of studies are examining the deteriorating impact of carbon emissions at the country or firm level, but the literature on the voluntary carbon disclosure project (CDP) by cities is not rich. Therefore, this study seeks to examine the effect of the population (Pop) and gross domestic product (GDP) on carbon emissions of cities by using data of CDP. The dataset refers to a set of numerous cities from around the world, spanning the period from 2012 to 2016. Random effects panel regression and generalized method of moments (GMM), and quantile regressions techniques have been employed to empirically investigate the discussed relationship and to control the potential endogeneity issues, respectively. According to the results, population and GDP are substantial predictors of carbon emissions in sampled cities. Findings show that not only factories contribute to increasing carbon emissions rate, but cities are equally responsible for these emissions as they put no checks on their economic growth and population. The findings are also robust for policy implications.