bluuebunny/crossref_metadata_2025_split huggingface dataset:
Static MLC transmission simulation using two‐dimensional ray tracing
Authors: Adam David P. , Bednarz Bryan P. , Frigo Sean P. 
Published: May 2022

AbstractPurposeWe investigated the hypothesis that the transmission function of rounded end linearly traveling multileaf collimators (MLCs) is constant with position. This assumption is made by some MLC models used in clinical treatment planning systems (TPSs) and in the Varian MLC calibration convention. If not constant, this would have implications for treatment plan QA results.MethodsA two‐dimensional ray‐tracing tool to generate transmission curves as a function of leaf position was created and validated. The curves for clinically available leaf tip positions (−20 to 20 cm) were analyzed to determine the location of the beam edge (half‐attenuation X‐ray [XR]) location, the beam edge broadening (BEB, 80%–20% width), as well as the leaf tip zone width. More generalized scenarios were then simulated to elucidate trends as a function of leaf tip radius.ResultsIn the analysis of the Varian high‐definition MLC, two regions were identified: a quasi‐static inner region centered about central axis (CAX), and an outer one, in which large deviations were observed. A phenomenon was identified where the half‐attenuation ray position, relative to that of the tip or tangential ray, increases dramatically at definitive points from CAX. Similar behavior is seen for BEB. An analysis shows that as the leaf radius parameter value is made smaller, the size of the quasi‐static region is greater (and vice versa).ConclusionThe MLC transmission curve properties determined by this study have implications both for MLC position calibrations and modeling within TPSs. Two‐dimensional ray tracing can be utilized to identify where simple behaviors hold, and where they deviate. These results can help clinical physicists engage with vendors to improve MLC models, subsequent fluence calculations, and hence dose calculation accuracy.
Surface Interactions of Oxygen Suffice to P‐Dope the Halide Perovskites
Authors: Halder Ansuman , Itzhak Anat , Hodesh Eli Rosh , Tirosh Shay , Cahen David 
Published: May 2022

AbstractAttempts to dope halide perovskites (HaPs) extrinsically have been mostly unsuccessful. Still, oxygen (O2) is an efficient p‐dopant for polycrystalline HaP films. To an extent, this doping is reversible, i.e., the films can be de‐doped by decreasing the O2 partial pressure. Here results are reported, aimed at understanding the mechanism of such reversible doping, as it has been argued that doping involves interaction of oxygen with defects inside bulk HaP. These experimental results clearly point out that O2‐surface interactions suffice to dope the bulk of the films. Such behavior fits what is known for other polycrystalline semiconductors, where surface charge transfer‐adducts can form and be removed. Thus, controlling the O2 partial pressure to which the HaP film is exposed, can, after proper encapsulation, achieve the desired bulk doping of the film.
Rhodium(II)‐Catalyzed Site‐Selective Intramolecular Insertion of Aryldiazoacetates into Unactivated Primary C−H Bond: A Direct Route to 2‐Unsubstituted Indanes
Authors: Nambu Hisanori , Amano Ryoya , Tamura Takafumi , Yakura Takayuki 
Published: May 2022

AbstractDirhodium(II)‐catalyzed intramolecular insertion of aryldiazoacetates into an unactivated primary C−H bond was described in this study. The insertion reaction of aryldiazoacetates with ortho‐isopropyl or ortho‐ethyl groups in the presence of a catalytic amount of dirhodium(II) tetrakis(triphenylacetate), Rh2(tpa)4, at room temperature proceeded site‐selectively to afford 2‐unsubstituted indane‐1‐carboxylates in 75%–96% yields. In the case of o‐isopropyl‐substituted aryldiazoacetates, cis‐isomers were obtained as major products. Furthermore, a chemoselective C−H insertion reaction of aryldiazoacetate bearing 1‐oxyethyl‐substituent at the ortho position was achieved by using a bulky and electron‐deficient pivaloyl group as the protecting group of a highly active oxygen atom. The present reaction provided a direct route to 2‐unsubstituted indanes.magnified image
Visible‐Light‐Promoted Radical Cyclization and N−N Bond Cleavage Relay of N‐Aminopyridinium Ylides for Access to 2,3‐Difunctionalized Indoles
Authors: Xu Meng‐Meng , Cao Wen‐Bin , Xu Xiao‐Ping , Ji Shun‐Jun 
Published: May 2022

AbstractReported herein is a photocatalytic platform for the vicinal aminopyridylation of indoles. The accurate difunctionalization reaction undergoes a tandem process involving a radical‐mediated 1,3‐dipolar cycloaddtion which generated from the single‐electron oxidation of N‐aminopyridinium ylides, a cleavage of the N−N bond as well as an oxidation of indoline ring. The electrophilic pyridyl and nucleophilic amino groups can be installed simultaneously into a wide range of indoles under mild and metal‐free conditions. Moreover, the protocol shows high levels of step and atom economy.magnified image
A Method for Locating the Real Roots of the Symbolic Quintic Equation Using Quadratic Equations
Authors: Prodanov Emil M. 
Published: May 2022

AbstractA method is proposed with which the locations of the roots of the monic symbolic quintic polynomial can be determined using the roots of two resolvent quadratic polynomials: and , whose coefficients are exactly those of the quintic polynomial. The different cases depend on the coefficients of and and on some specific relationships between them. The method is illustrated with the full analysis of one of the possible cases. Some of the roots of the symbolic quintic equation for this case have their isolation intervals determined and, as this cannot be done for all roots with the help of quadratic equations only, finite intervals containing 1 or 3 roots, or 0 or 2 roots, or, rarely, 0, or 2, or 4 roots of the quintic are identified. Knowledge of the stationary points of the quintic lifts this indeterminacy and allows finding the isolation interval of each root. Separately, using the complete root classification of the quintic, one can also lift this indeterminacy. The method also allows to see how variation of the individual coefficients of the quintic affect its roots. No root finding iterations or any numerical approximations are used and no equations of degree higher than two are solved.
Hot Carrier Transport and Carrier Multiplication Induced High Performance Vertical Graphene/Silicon Dynamic Diode Generator
Authors: Lu Yanghua , Shen Runjiang , Yu Xutao , Yuan Deyi , Zheng Haonan , Yan Yanfei , Liu Chang , Yang Zunshan , Feng Lixuan , Li Linjun , Lin Shisheng 
Published: May 2022

AbstractDynamic semiconductor diode generators (DDGs) offer a potential portable and miniaturized energy source, with the advantages of high current density, low internal impedance, and independence of the rectification circuit. However, the output voltage of DDGs is generally as low as 0.1–1 V, owing to energy loss during carrier transport and inefficient carrier collection, which requires further optimization and a deeper understanding of semiconductor physical properties. Therefore, this study proposes a vertical graphene/silicon DDG to regulate the performance by realizing hot carrier transport and collection. With instant contact and separation of the graphene and silicon, hot carriers are generated by the rebounding process of built‐in electric fields in dynamic graphene/silicon diodes, which can be collected within the ultralong hot electron lifetime of graphene. In particular, monolayer graphene/silicon DDG outputs a high voltage of 6.1 V as result of ultrafast carrier transport between the monolayer graphene and silicon. Furthermore, a high current of 235.6 nA is generated due to the carrier multiplication in graphene. A voltage of 17.5 V is achieved under series connection, indicating the potential to supply electronic systems through integration design. The graphene/silicon DDG has applications as an in situ energy source for harvesting mechanical energy from the environment.
Epidemiology, Survival, and Clinical Characteristics of Inclusion Body Myositis
Authors: Lindgren Ulrika , Pullerits Rille , Lindberg Christopher , Oldfors Anders 
Published: May 2022

ObjectiveWe performed a population‐based study on inclusion body myositis with the primary aims to define the prevalence, survival rate, and incidence, and to investigate the symptom profiles associated with disease duration and sex over a 33‐year period.MethodsPatients diagnosed between 1985 and 2017 in Region Västra Götaland, Sweden, were identified according to the European Neuromuscular Centre diagnostic criteria from 2011.ResultsWe identified 128 patients, 89 men and 39 women, with the strict clinicopathological definition of inclusion body myositis. The prevalence was 32 per million inhabitants, 19 per million women and 45 per million men, by December 31, 2017. Mean incidence was 2.5 per million inhabitants and year. Mean age at symptom onset was 64.4 years with quadriceps weakness being the most common presenting symptom followed by finger flexor weakness. Dysphagia was a common presenting symptom being more frequent in women (23%) than men (10%) and was during the disease course reported in 74% of men and 84% of women. Seventy‐three patients were deceased, with a mean survival of 14 years from symptom onset. Survival rates from both diagnosis date and symptom onset were decreased compared to the matched population.Twenty‐one percent of the patients had an additional autoimmune disease. A cross‐sectional analysis of autoantibodies in 50 patients and 28 matched controls showed autoantibodies to cytosolic 5′‐nucleotidase 1A in 40% of the patients and 3.6% of controls.InterpretationInclusion body myositis is an autoimmune disease with decreased survival rate and with marked sex differences in both prevalence and clinical manifestations. ANN NEUROL 2022;92:201–212
Collective Total Syntheses of Five Lycopodium Alkaloids
Authors: He Feifei , Feng Shangbiao , Zhao Yulong , Shi Hongliang , Duan Xiaoguang , Li Huilin , Xie Xingang , She Xuegong 
Published: May 2022

AbstractIt is reported herein that by exploiting the commonly shared bicyclic decahydroquinoline motif, a gold‐catalyzed enamide–alkyne cycloisomerization reaction is developed to access tricyclic cores in a simple way. These tricyclic cores further serve as an advanced platform for the divergent enantioselective collective total syntheses of five Lycopodium alkaloids, belonging to three different structural types, in a concise and protecting‐group‐free fashion. The key transformations in the second phase include: 1) a transannular reductive Heck cyclization for installation of the azepane ring in fawcettidine, fawcettimine, and lycoposerramine Q; 2) a domino Mukaiyama hydration/Grob fragmentation process for construction of the ten‐membered lactam system in phlegmariurine B; 3) a Fukuyama one‐pot protocol for the construction of the 2‐pyridone motif in lycoposerramine R. The newly developed strategy is expected to pave the way for the synthesis of other structurally related Lycopodium alkaloids.
Formation of a Hybrid 1‐Bora‐3‐boratabenzene Heteroarene Anion Derivative
Authors: Sun Qiu , Daniliuc Constantin G. , Mück‐Lichtenfeld Christian , Kehr Gerald , Erker Gerhard 
Published: May 2022

AbstractThe B(C6F5)2‐substituted borole 2⋅SMe2 was obtained from the phenyl bis(trimethylsilylethynyl) borane SMe2 adduct (1⋅SMe2) by a synthetic sequence containing a rare 1,1‐hydroboration reaction. Subsequent thermolysis at 50 °C converted it to the bicyclic borenium/borate zwitterion 3⋅SMe2. Photolysis of 3⋅SMe2 gave the diboracyclohexadiene derivative 4⋅SMe2, which after ligand exchange with N,N‐dimesitylimidazolylidene and deprotonation gave the 1‐bora‐3‐boratabenzene anion derivative as its potassium salt 6. Some unique follow‐up reactions of the unsaturated diboron containing six‐membered heterocycles were investigated.
Fluorescence or Phosphorescence? The Metallic Composition of the Nanocluster Kernel Does Matter
Authors: Zhu Chen , Xin Junsheng , Li Jing , Li Hao , Kang Xi , Pei Yong , Zhu Manzhou 
Published: May 2022

AbstractIt remains challenging to manipulate the nature of photoluminescence as either fluorescence or phosphorescence for a correlated cluster series. In this work, two correlated nanoclusters, Au5Ag11(SR)8(DPPOE)2 and Pt1Ag16(SR)8(DPPOE)2 with comparable structure features, were synthesized and structurally determined. These two alloy nanoclusters displayed distinct photoluminescent nature—the Au5Ag11 nanocluster is fluorescent, whereas the Pt1Ag16 nanocluster is phosphorescent. The decay processes of the excited electrons in these two nanoclusters have been explicitly mapped out by both experimental and theoretical approaches, disclosing the mechanisms of their fluorescence and phosphorescence. Specifically, the metallic compositions of the nanocluster kernels mattered in determining their photoluminescent nature. The results herein provide an intriguing nanomodel that enables us to grasp the origin of photoluminescence at the atomic level, which further paves the way for fabricating novel nanoclusters or cluster‐based nanomaterials with customized photophysical properties.
Effects of polyvinylidene fluoride substrate characteristics on the selectivity of thin‐film composite nanofiltration membrane
Authors: Zhu Chenyu , Zhang Xue , Li Fuzhi , Zhao Xuan 
Published: May 2022

AbstractThin‐film composite (TFC) nanofiltration (NF) membranes have been fabricated on polyvinylidene fluoride (PVDF) substrates to separate Cl− and SO42−. With increasing polyvinylpyrrolidone (PVP) content (0–1.00 wt%) in PVDF casting solution, the corresponding substrates have similar surface pore size and hydrophilicity, but have enlarged surface porosity and bulk pore size. Obvious defects were found on TFC membrane surface, which were fabricated on the substrate with large and deep finger‐like pores. On such substrates, piperazine solution is prone to sink to the pore bottom and cannot react with trimesoyl chloride to form a defect‐free polyamide layer. Different from previous reports, the bulk pore size and structure, especially for the finger‐like pore, is found to be a key factor influencing the interfacial polymerization (IP) process. The optimal TFC membrane was prepared on the substrate with 0.15 wt% PVP in casting solution, which had crater‐shaped ridge‐valley structures, relatively high permeability and the largest separation factor of 4.66 for Cl− and SO42−. Although the NF performance needs to be further improved, the results shed lights on the important effects of the substrate bulk pore size and structure on the IP process, which will enlarge the knowledge on the impact of substrate on IP process.
Influence of process parameters on the formation of inhalable fiber dust during shredding for mechanical recycling of fiber‐reinforced organo sheets
Authors: Tölle Lisa , Hopp Matthias 
Published: May 2022

AbstractShredding is a major process step in mechanical recycling, as the plastic scrap needs to be cut into small pieces for further processing. It will be melted and finally injection‐molded to form new plastic parts. Also for fiber‐reinforced thermoplastics, the mechanical recycling process is an ecofriendly process because all resources are reused. One challenge during the shredding of fiber‐reinforced plastics is the fiber dust formation. The fiber dust disturbs the following production processes, and the fiber fragments can be alveolar and thus potentially toxic. Therefore, it is a major aim of this research to optimize the cutting process by investigating the effect of different shredding parameters on the alveolar fiber dust formation. Three different continuous fiber‐reinforced thermoplastic organo sheets (PP with glass fibers, PA6 with glass fibers, PA66 with carbon fibers) are shredded while the parameters of throughput, rotational speed, screen size and feedstock size are varied. The results show no clear effect of the throughput either on the amount of fine particles nor on the number of short fibers after removal of the plastic matrix for all materials. Reducing the screen size in the cutting mill leads to a large increase in the amount of fine particles and on the number of short fiber fragments. Additionally, the rotational speed has a large impact on the amount of fine particles. With increasing rotational speed, the number of fine particles rises, whereas there is no major effect on the fiber length distribution. The investigations relating the rotational speed are valid for all materials, throughput, screen sizes and feedstock sizes. Decreasing the feedstock size leads to an increasing amount of fine particles with no change in fiber length distribution for the glass fiber‐reinforced organo sheets. For the carbon fiber‐reinforced materials, it does not lead to any change in the amount of fiber dust but to an increase in shorter fibers. Thus this parameter seems to be material dependent. Images taken by a scanning electron microscope show alveolar fiber dust fragments in the ground material of all samples.
Cultural determinants in infants and infantile determinants in cultural practices
Authors: Dajani Karim G. 
Published: May 2022

AbstractThis article is adapted from a panel presentation given at the International Psychoanalytical Association Congress in the summer of 2020. It argues for the centrality of cultural determinants in infant development and the centrality of infantile modes of consciousness in our cultural practices. It suggests that the inculcation of shared systems of meaning‐making, referring to cultures or ideologies, are antecedent to any sort of meaningful infant development. Culture is a medium, a common ground that is both external and mental. It provides the necessary tools for infants to develop the capacity to re‐present experience along lines that are prescribed and recognized by the large group or collective in which the dyad (mother–infant) and triad (oedipal family) are embedded. The analysis of the individual's lived experiences in the context of dependence on their parents/family is necessary to understand the composition and function of our patients' unconscious. We propose extending our lens to include the analysis of social and cultural derivatives, the impact of the systems that suffuse us, on our unconscious and lived experience. Doing so will extend our relevance and shine a beacon in previously neglected regions of the human unconscious that are ‘fundamentally social’.
Optimal shock‐based maintenance policy for a system in a dynamic environment
Authors: Misaii Hasan , Haghighi Firoozeh , Fouladirad Mitra 
Published: May 2022

AbstractIn this article, we consider a single‐unit system that operates in a dynamic environment and is subject to shocks. Shocks only affect the system (nonlethal shock) and do not cause sudden failure, and arrive according to a counting process. Both homogeneous and nonhomogeneous Poisson processes are considered for shocks arrival modeling. In order to model the dynamic environment and consider shock effects, a multiplicative failure rate model is proposed. Both corrective maintenance and shock‐based preventive maintenance are considered, and two policies are proposed. In the first proposed policy, the system is replaced by a new one upon a failure or based on the predetermined number of shocks, whichever comes first, while the second proposed policy extends the first one by considering an imperfect preventive repair at each inspection time. The inspection times are periodic and the interinspection interval is considered as a decision variable. The proposed policies are optimized according to long‐run cost rate criteria. Numerical examples illustrate the applicability and efficiency of the proposed policies.
AmicroRNAor messengerRNApoint of departure estimates an apical endpoint point of departure in a rat developmental toxicity model
Authors: Johnson Kamin J. , Costa Eduardo , Marshall Valerie , Sriram Shreedharan , Venkatraman Anand , Stebbins Kenneth , LaRocca Jessica 
Published: May 2022

AbstractTraditional developmental toxicity testing practice examines fetal apical endpoints to identify a point of departure (POD) for risk assessment. A potential new testing paradigm involves deriving a POD from a comprehensive analysis of molecular‐level change. Here, the rat ketoconazole endocrine‐mediated developmental toxicity model was used to test the hypothesis that maternal epigenomic (miRNA) and transcriptomic (mRNA) PODs are similar to fetal apical endpoint PODs. Sprague–Dawley rats were exposed from gestation day (GD) 6–21 to 0, 0.063, 0.2, 0.63, 2, 6.3, 20, or 40 mg/kg/day ketoconazole. Dam systemic, liver, and placenta PODs, along with GD 21 fetal resorption, body weight, and skeletal apical PODs were derived using BMDS software. GD 21 dam liver and placenta miRNA and mRNA PODs were obtained using three methods: a novel individual molecule POD accumulation method, a first mode method, and a gene set method. Dam apical POD values ranged from 2.0 to 38.6 mg/kg/day; the lowest value was for placenta histopathology. Fetal apical POD values were 10.9–20.3 mg/kg/day; the lowest value was for fetal resorption. Dam liver miRNA and mRNA POD values were 0.34–0.69 mg/kg/day, and placenta miRNA and mRNA POD values were 2.53–6.83 mg/kg/day. Epigenomic and transcriptomic POD values were similar across liver and placenta. Deriving a molecular POD from dam liver or placenta was protective of a fetal apical POD. These data support the conclusion that a molecular POD can be used to estimate, or be protective of, a developmental toxicity apical POD.
Outsourcing logistics operations in circular economy towards to sustainable development goals
Authors: Zarbakhshnia Navid , Govindan Kannan , Kannan Devika , Goh Mark 
Published: May 2022

AbstractOne of novel manners to achieve sustainable development is concentrating on circular economy in order to manage greenhouse gas emissions, energy consumption, and waste. It also helps to protect the environment and optimize usage of input resources. The main element of circular economy is closed‐loop supply chain which covers both forward and reverse products flows. This study aims to outsource logistics operations in a closed‐loop supply chain. An innovative analytical multi‐step fuzzy decision‐making method is proposed to rank sustainable third‐party logistics service providers (3PLSPs). Fuzzy Decision‐Making Trial and Evaluation Laboratory (DEMATEL) is first used to evaluate the relationships among the main criteria. Then, fuzzy analytic network process (ANP) is applied to weight the determined set of criteria. In order to develop the hybrid fuzzy DEMATEL‐ANP method and to simplify the computation, the expert judgment method is used between the two techniques as a middle step to reduce the number of criteria. As many of the criteria overlap with each other on content and context, expert opinions are used to shortlist and rank the criteria. Finally, the 3PLSPs are ranked through the fuzzy complex proportional assessment (COPRAS) method. To validate the practicability and applicability of the improved decision‐making model, a household appliance case study is applied with data obtained from industry experts. In this case, five service providers are considered and ranked, while the first one gets the best score. A sensitivity analysis is performed by altering the criteria weights to validate the proposed approach, data, and the obtained results. In terms business and the environment, this study provides success critical criteria for decision‐making problems in circular economy for addressing sustainable development.