bluuebunny/crossref_metadata_2025 huggingface dataset:
The sun diver: Combining solar sails with the Oberth effect
Authors: Bailer-Jones Coryn A. L.
Published: February 2021

A highly reflective sail provides a way to propel a spacecraft out of the solar system using solar radiation pressure. The closer the spacecraft is to the Sun when it starts its outward journey, the larger the radiation pressure and so the larger the final velocity. For a spacecraft starting on the Earth's orbit, closer proximity can be achieved via a retrograde impulse from a rocket engine. The sail is then deployed at the closest approach to the Sun. Employing the so-called Oberth effect, a second, prograde, impulse at closest approach will raise the final velocity further. Here, I investigate how a fixed total impulse (Δv) can best be distributed in this procedure to maximize the sail's velocity at infinity. Once Δv exceeds a threshold that depends on the lightness number of the sail (a measure of its sun-induced acceleration), the best strategy is to use all of the Δv in the retrograde impulse to dive as close as possible to the Sun. Below the threshold, the best strategy is to use all of the Δv in the prograde impulse and thus not to dive at all. Although larger velocities can be achieved with multi-stage impulsive transfers, this study shows some interesting and perhaps counter-intuitive consequences of combining impulses with solar sails.
Active learning in a graduate quantum field theory course
Authors: Lepage G. Peter
Published: February 2021

This article describes how the author successfully adapted techniques drawn from the literature on active learning for use in a graduate-level course on quantum field theory. Students completed readings and online questions ahead of each class and spent class time working through problems that required them to practice the decisions and skills typical of a theoretical physicist. The instructor monitored these activities and regularly provided timely feedback to guide their thinking. Instructor-student interactions and student enthusiasm were similar to that encountered in one-on-one discussions with advanced graduate students. Course coverage was not compromised. The teaching techniques described here are well suited to other advanced courses.
Understanding and enhancing the impact-induced tension of a falling chain
Authors: Pantaleone J.
Published: February 2021

When a falling chain strikes a surface, it can accelerate downwards faster than free-fall. This counterintuitive effect occurs when a tension is created in the chain above where it strikes the surface. The size of this tension, and how it is produced, depend on the type of chain used. For a chain made of rods that are slightly tilted from horizontal, the impact-induced tension is readily observable. Here are reported experimental observations on such a falling chain for two different situations: when the chain strikes an inclined surface, and when the chain's mass density decreases with height. It is found that both of these arrangements can increase the downward acceleration. To quantitatively describe these observations, a theoretical model is developed. The model successfully predicts the chain's position and velocity, even when the top end approaches the surface, without any free parameters. The model also predicts that uniform rods are practically the best for producing large tensions.
Resolving tensions surrounding massive pulleys
Authors: Durian D. J. , Kroll J. , Mele E. J.
Published: February 2021

The distribution of string tension on the contact line between an ideal string and a massive pulley is a frequently discussed but incompletely posed problem that confronts students in introductory mechanics. We highlight ambiguities in the usual presentation of this problem by the massive Atwood's machine and discuss two compact resolutions that treat situations where the pulley or the string elastically deforms. We propose experiments that can be developed in an intermediate laboratory to determine the tension profile.
Transcriptome Analysis of Listeria monocytogenes Exposed to Beef Fat Reveals Antimicrobial and Pathogenicity Attenuation Mechanisms
Authors: Chen Yuan Yao , Kommadath Arun , Vahmani Payam , Visvalingam Jeyachchandran , Dugan Michael E. R. , Yang Xianqin
Published: February 2021

Listeria monocytogenes
is a bacterial pathogen known for its ability to survive and thrive under adverse environments and, as such, its control poses a significant challenge, especially with the trend of minimally processed and ready-to-eat foods. This work investigated the effectiveness of fatty acids from various sources as natural antimicrobials against
L. monocytogenes
and evaluated their potential role in
L. monocytogenes
pathogenicity modulation, using the strain ATCC 19111.
Assessment of S1-, S2-, and NCP-Specific IgM, IgA, and IgG Antibody Kinetics in Acute SARS-CoV-2 Infection by a Microarray and Twelve Other Immunoassays
Authors: Semmler Georg , Traugott Marianna Theresia , Graninger Marianne , Hoepler Wolfgang , Seitz Tamara , Kelani Hasan , Karolyi Mario , Pawelka Erich , Aragón de La Cruz Sara , Puchhammer-Stöckl Elisabeth , Aberle Stephan Walter , Stiasny Karin , Zoufaly Alexander , Aberle Judith Helene , Weseslindtner Lukas
Published: February 2021

In this study, we comprehensively analyzed multispecific antibody kinetics of different immunoglobulins in hospitalized patients with acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Three hundred fifty-four blood samples longitudinally obtained from 81 IgG-seroconverting progressed coronavirus disease 2019 (CoVID-19) patients were quantified for spike 1 (S1), S2, and nucleocapsid protein (NCP)-specific IgM, IgA, IgG, and total Ig antibodies using a microarray, 11 different enzyme-linked immunosorbent assays (ELISAs)/chemiluminescence immunoassays (CLIAs), and 1 rapid test by seven manufacturers.
Prevalence of disabilities and non-communicable diseases in an elderly population in the Telangana state, India: a population-based cross-sectional study
Authors: Marmamula Srinivas , Modepalli Satya Brahmanandam , Kumbham Thirupathi Reddy , Challa Rajesh , Keeffe Jill E
Published: February 2021

Objectives

To assess the prevalence of disabilities (vision, hearing, mobility, cognitive, self-care and communication) and non-communicable diseases (NCDs) among the elderly population in two districts in Telangana, India.

Design

Population-based cross-sectional study using a cluster random sampling method to select the study clusters.

Setting

Elderly population in Khammam and Warangal districts were recruited. Detailed interviews were conducted by trained community health workers. Personal and demographic information such as age, gender, level of education and a self-report of NCDs was collected. The Washington Disability Questionnaire was administered to assess the presence of disabilities.

Participants

1821 participants aged ≥60 years, 54.5% were women, and 73.3% had no education.

Primary outcome measure

Prevalence of disabilities and NCDs.

Results

Overall, the prevalence of at least disability was 20.3% (95% CI 16.3 to 24.9). The prevalence of self- reported disabilities were: seeing (5.9%; 95% CI 4.4 to 7.8), mobility (12.8%; 95% CI 9.7 to 16.8), hearing (3.6%; 95% CI 2.7 to 4.8), cognition (4.8%; 95% CI 3.5 to 6.7), self-care (3.3%; 95% CI 2.3 to 4.7) and communication (1.8%; 95% CI 1.2 to 2.6). Overall, the prevalence of at least one NCD was 34.2% (95% CI 30.9 to 37.7). Hypertension was the most common systemic condition (25.4%; 95% CI 22.4 to 28.7), followed by diabetes (9.0%; 95% CI 7.3 to 11.0), and body pains (muscle-skeletal) (9.9%; 95% CI 8.1 to 12.2).

Conclusion

Every fifth elderly person in the districts of Khammam and Warangal in Telangana had at least one self-reported disability. Besides, a third of the elderly had at least one NCD. There is a definite need to develop comprehensive public health strategies to address disabilities and NCDs in Telangana.
Prospective, randomised, multicentre, open-label trial, designed to evaluate the best timing of closure of the temporary ileostomy (early versus late) in patients who underwent rectal cancer resection and with indication for adjuvant chemotherapy: the STOMAD (STOMa closure before or after ADjuvant therapy) randomised controlled trial
Authors: Massucco Paolo , Fontana Andrea , Mineccia Michela , Perotti Serena , Ciccone Giovannino , Galassi Claudia , Giuffrida Maria Carmela , Marino Donatella , Monsellato Igor , Paris Myriam Katja , Perinotti Roberto , Racca Patrizia , Monagheddu Chiara , Saccona Fabio , Ponte Elisa , Mistrangelo Massimiliano , Santarelli Mauro , Tomaselli Francesco , Reddavid Rossella , Birolo Simone , Calabrò Marcello , Pipitone Nicoletta , Panier Suffat Luca , Carrera Monica , Potente Francesco , Brunetti Marco , Rimonda Roberto , Adamo Vincenzo , Piscioneri Domenico , Cravero Francesca , Serventi Alberto , Giaminardi Eliana , Mazza Luca , Bellora Paolo , Colli Fabio , De Rosa Clemente , Battafarano Francesco , Trapani Renza , Mellano Alfredo , Gibin Enrico , Bellomo Paola
Published: February 2021

Introduction

Temporary ileostomy is a valuable aid in reducing the severity of complications related to rectal cancer surgery. However, it is still unclear what is the best timing of its closure in relation to the feasibility of an adjuvant treatment, especially considering patient-reported outcomes and health system costs. The aim of the study is to compare the results of an early versus late closure strategy in patients with indication to adjuvant chemotherapy after resection for rectal cancer.

Methods and analysis

This is a prospective multicentre randomised trial, sponsored by Rete Oncologica Piemonte e Valle d’Aosta (Oncology Network of Piedmont and Aosta Valley-Italy). Patients undergone to rectal cancer surgery with temporary ileostomy, aged >18 years, without evidence of anastomotic leak and with indication to adjuvant chemotherapy will be enrolled in 28 Network centres. An early closure strategy (between 30 and 40 days from rectal surgery) will be compared with a late one (after the end of adjuvant therapy). Primary endpoint will be the compliance to adjuvant chemotherapy with and without ileostomy. Complications associated with stoma closure as well as quality of life, costs and oncological outcomes will be assessed as secondary endpoints.

Ethics and dissemination

The trial will engage the Network professional teams in a common effort to improve the treatment of rectal cancer by ensuring the best results in relation to the most correct use of resources. It will take into consideration both the patients’ point of view (patient-reported outcome) and the health system perspective (costs analysis). The study has been approved by the Ethical Review Board of Città della Salute e della Scienza Hospital in Turin (Italy). The results of the study will be disseminated by the Network website, medical conferences and peer-reviewed scientific journals.

Trial registration number

NCT04372992.
Metabolic phenotyping and cardiovascular disease: an overview of evidence from epidemiological settings
Authors: Iliou Aikaterini , Mikros Emmanuel , Karaman Ibrahim , Elliott Freya , Griffin Julian L , Tzoulaki Ioanna , Elliott Paul
Published: February 2021

Metabolomics, the comprehensive measurement of low-molecular-weight molecules in biological fluids used for metabolic phenotyping, has emerged as a promising tool to better understand pathways underlying cardiovascular disease (CVD) and to improve cardiovascular risk stratification. Here, we present the main methodologies for metabolic phenotyping, the methodological steps to analyse these data in epidemiological settings and the associated challenges. We discuss evidence from epidemiological studies linking metabolites to coronary heart disease and stroke. These studies indicate the systemic nature of CVD and identify associated metabolic pathways such as gut microbial cometabolism, branched-chain amino acids, glycerophospholipid and cholesterol metabolism, as well as activation of inflammatory processes. Integration of metabolomic with genomic data can provide new evidence for involved biochemical pathways and potential for causality using Mendelian randomisation. The clinical utility of metabolic biomarkers for cardiovascular risk stratification in healthy individuals has not yet been established. As sample sizes with high-dimensional molecular data increase in epidemiological settings, integration of metabolomic data across studies and platforms with other molecular data will lead to new understanding of the metabolic processes underlying CVD and contribute to identification of potentially novel preventive and pharmacological targets. Metabolic phenotyping offers a powerful tool in the characterisation of the molecular signatures of CVD, paving the way to new mechanistic understanding and therapies, as well as improving risk prediction of CVD patients. However, there are still challenges to face in order to contribute to clinically important improvements in CVD.
Real-life use of talimogene laherparepvec (T-VEC) in melanoma patients in centers in Austria, Switzerland and Germany
Authors: Ressler Julia Maria , Karasek Matthias , Koch Lukas , Silmbrod Rita , Mangana Joanna , Latifyan Sofiya , Aedo-Lopez Veronica , Kehrer Helmut , Weihsengruber Felix , Koelblinger Peter , Posch Christian , Kofler Julian , Michielin Olivier , Richtig Erika , Hafner Christine , Hoeller Christoph
Published: February 2021

Background

Talimogene laherparepvec (T-VEC) is a licensed therapy for use in melanoma patients of stage IIIB-IVM1a with injectable, unresectable metastatic lesions in Europe. Approval was based on the Oncovex Pivotal Trial in Melanoma study, which also included patients with distant metastases and demonstrated an overall response rate (ORR) of 40.5% and a complete response (CR) rate of 16.6%.

Objectives

The aim of this study was to assess the outcome of melanoma patients treated with T-VEC in a real-life clinical setting.

Methods

Based on data from 10 melanoma centers in Austria, Switzerland and southern Germany, we conducted a retrospective chart review, which included 88 patients (44 male, 44 female) with a median age of 72 years (range 36–95 years) treated with T-VEC during the period from May 2016 to January 2020.

Results

88 patients fulfilled the inclusion criteria for analysis. The ORR was 63.7%. 38 patients (43.2%) showed a CR, 18 (20.5%) had a partial response, 8 (9.1%) had stable disease and 24 (27.3%) patients had a progressive disease. The median treatment period was 19 weeks (range: 1–65), an average of 11 doses (range: 1–36) were applied. 39 (45.3%) patients developed adverse events, mostly mild, grade I (64.1%).

Conclusion

This real-life cohort treatment with T-VEC showed a high ORR and a large number of durable CRs.
Informed consent and compulsory medical device registries: ethics and opportunities
Authors: Kramer Daniel B. , Parasidis Efthimios
Published: February 2021

Many high-risk medical devices earn US marketing approval based on limited premarket clinical evaluation that leaves important questions unanswered. Rigorous postmarket surveillance includes registries that actively collect and maintain information defined by individual patient exposures to particular devices. Several prominent registries for cardiovascular devices require enrolment as a condition of reimbursement for the implant procedure, without informed consent. In this article, we focus on whether these registries, separate from their legal requirements, have an ethical obligation to obtain informed consent from enrolees, what is lost in not doing so, and the ways in which seeking and obtaining consent might strengthen postmarket surveillance in the USA.
COVID-19 in patients with heart failure: the new and the old epidemic
Authors: Sisti Nicolò , Valente Serafina , Mandoli Giulia Elena , Santoro Ciro , Sciaccaluga Carlotta , Franchi Federico , Cameli Paolo , Mondillo Sergio , Cameli Matteo
Published: February 2021

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has spread in nearly 200 countries in less than 4 months since its first identification; accordingly, the coronavirus disease 2019 (COVID 2019) has affirmed itself as a clinical challenge. The prevalence of pre-existing cardiovascular diseases in patients with COVID19 is high and this dreadful combination dictates poor prognosis along with the higher risk of intensive care mortality. In the setting of chronic heart failure, SARS-CoV-2 can be responsible for myocardial injury and acute decompensation through various mechanisms. Given the clinical and epidemiological complexity of COVID-19, patiens with heart failure may require particular care since the viral infection has been identified, considering an adequate re-evaluation of medical therapy and a careful monitoring during ventilation.
Google shopping queries for vaping products, JUUL and IQOS during the E-cigarette, or Vaping, product use Associated Lung Injury (EVALI) outbreak
Authors: Leas Eric C , Moy Natalie H , Nobles Alicia L , Ayers John , Zhu Shu-Hong , Purushothaman Vidya
Published: February 2021

Objectives

To assess whether the late 2019 US outbreak of pulmonary disease linked to vaping (‘E-cigarette, or Vaping, product use Associated Lung Injury’ (EVALI)) impacted online shopping queries for vaping products and the Philip Morris ‘IQO’ brand of heated tobacco.

Methods

We tracked online shopping queries for vape(s), JUUL and IQOS by analysing rates of Google queries indicative of shopping (eg, buy IQOS) after news of the outbreak was first reported (the week of 29 July 2019) until hospitalisations ceased (the week of 16 February 2020). We compared observed rates of shopping during the outbreak to counterfactual expected rates that were predicted using an autoregressive iterative moving average model fit to queries from 1 January 2014 to the week of 21 July 2019.

Results

During the outbreak, vape shopping queries were 34% (95% CI 30% to 38%) lower than expected and JUUL shopping queries were 39% (95% CI 34% to 45%) lower than expected, translating into about 7.2 and 1.0 million fewer searches. IQOS shopping queries were 58% (95% prediction interval (PI): 34–87) higher than expected, translating into 35 000 more searches. Moreover, IQOS shopping queries reached a historic high the week they were discussed as a potentially safe alternative to vaping (the week of 29 September 2019), when they were 382% (95% PI: 219–881) above expected rates for the week.

Conclusions

These results suggest that unplanned events, such as the EVALI outbreak, can provoke changes in the epidemiology of product usage. Tobacco companies should be prohibited from using events such as disease outbreaks to position their products as less harmful without prior approval.
Production of light nuclei in heavy ion collisions via hagedorn resonances
Authors: Gallmeister K. , Greiner C.
Published: February 2021

The physical processes behind the production of light nuclei in heavy ion collisions are unclear. The successful theoretical description of experimental yields by thermal models conflicts with the very small binding energies of the observed states, being fragile in such a hot and dense environment. Other available ideas are delayed production via coalescence, or a cooling of the system after the chemical freeze-out according to a Saha equation, or a ‘quench’ instead of a thermal freeze-out. A recently derived prescription of an (interacting) Hagedorn gas is applied to consolidate the above pictures. The tabulation of decay rates of Hagedorn states into light nuclei allows to calculate yields usually inaccessible due to very poor Monte Carlo statistics. Decay yields of stable hadrons and light nuclei are calculated. While the scale-free decays of Hagedorn states alone are not compatible with the experimental data, a thermalized hadron and Hagedorn state gas is able to describe the experimental data. Applying a cooling of the system according to a Saha-equation with conservation of nucleon and anti-nucleon numbers leads to (nearly) temperature independent yields, thus a production of the light nuclei at temperatures much lower than the chemical freeze-out temperature is compatible with experimental data and with the statistical hadronization model.
Position uncertainties of AGATA pulse-shape analysis estimated via the bootstrapping method
Authors:   AGATA and OASIS collaborations, Siciliano M. , Ljungvall J. , Goasduff A. , Lopez-Martens A. , Zielińska M.
Published: February 2021

The unprecedented capabilities of state-of-the-art segmented germanium-detector arrays, such as AGATA and GRETA, derive from the possibility of performing pulse-shape analysis. The comparison of the net- and transient-charge signals with databases via grid-search methods allows the identification of the $$\gamma $$
γ
-ray interaction points within the segment volume. Their precise determination is crucial for the subsequent reconstruction of the $$\gamma $$
γ
-ray paths within the array via tracking algorithms, and hence the performance of the spectrometer. In this paper the position uncertainty of the deduced interaction point is investigated using the bootstrapping technique applied to $$^{60}$$

60

Co radioactive-source data. General features of the extracted position uncertainty are discussed as well as its dependence on various quantities, e.g. the deposited energy, the number of firing segments and the segment geometry.
Novel Meminductor Emulators Using Operational Amplifiers and their Applications in Chaotic Oscillators
Authors: Singh Aneet , Rai Shireesh Kumar
Published: February 2021

This paper presents six different meminductor emulator circuits based on operational amplifiers. Five circuits of meminductor emulators have been proposed using two operational amplifiers, one memristor, three resistors and one capacitor, whereas the sixth circuit uses two operational amplifiers, two memristors, one resistor and two capacitors. All circuits of the proposed meminductor emulators are very simple over most of the realizations of meminductor emulators in the literature. The behaviors of meminductor emulators are satisfactory over a wide range of frequencies. The proposed configurations of meminductor emulators have been simulated by the LTspice tool. The SPICE models of both operational amplifier (AD711) and memristor have been used for simulation. The workability of the proposed meminductor emulators has also been verified using the basic and well-known structure of operational amplifier. In addition, the pinched hysteresis loop obtained by the simulation results of meminductor emulator has been achieved by the experimental results as well. Chaotic oscillator has been designed using the proposed meminductor emulator to prove the worthiness of the design.
Analytical Solution for Sound Radiation Characteristics of Graphene Nanocomposites Plate: Effect of Porosity and Variable Edge Load
Authors: Gunasekaran Vijay , Pitchaimani Jeyaraj , Chinnapandi Lenin Babu Mailan , Kumar Ashish
Published: February 2021

The effects of graded dispersion of graphene platelets and porosity on vibro-acoustics of nanocomposite plate exposed to variable edge loads are analytically investigated. Voigt and Halpin–Tsai micromechanics model is used to obtain effective properties of the porous graphene nanocomposites. The strain energy technique is implemented to estimate the buckling load ([Formula: see text]). By means of Reddy’s third-order shear deformation theorem and Rayleigh Integral, vibration and acoustic responses are obtained. After validating the present analysis with the published results, the nature of edge loads on buckling and vibro-acoustic response is significant. It is noted that an increase in the intensity of non-uniform in-plane loads leads to changes in free vibration modes and resonant amplitude of response. The weight percentage and grading pattern of graphene reinforcement cause the stiffness hardening effect, whereas porosity distribution and coefficients cause the stiffness softening effect on the nanocomposite plate. It is found that the plate with symmetric distribution of graphene platelets with more concentration at the surface and symmetric porosity variation with more porosity at the center radiates less sound power.
Preparation and Effect of Selenium Nanoparticles/Oligochitosan on the White Blood Cell Recovery of Mice Exposed to Gamma-Ray Radiation
Authors: Nguyen Duy Ngoc , Van Dang Phu , Le Quoc Anh , Kim Nguyen Lan Thi , Nguyen Hien Quoc , Thu Tran Ngan Thi , Le Bao Tran Ha , Phan Tuan Dinh , Bui Ha Manh
Published: February 2021

Owing to their excellent bioavailability, high bioactivity, and low toxicity, selenium nanoparticles (SeNPs) are emerging nanomaterials. In this study, SeNPs with a size of ∼41.8 nm were synthesised by γ-irradiation using oligochitosan (OCS) as the stabiliser. As-synthesized SeNPs/OCS were characterised by UV-Vis spectroscopy, transmission electron microscopy, and energy-dispersive X-ray (EDX) analysis. Results revealed that the as-obtained SeNP/OCS powder exhibits high purity. The SeNP/OCS solution’s stability test results indicated that the SeNP/OCS solution stored at 4°C exhibits good stability for 60 days. The SeNP/OCS solution was unstable at ambient temperature, and SeNP/OCS exhibited agglomeration after about 15 days. SeNP/OCS products recovered the total white blood cells of γ-ray irradiated mice. The SeNP/OCS product, which was synthesised by a green approach, with high purity and efficient recuperation of white blood cells, can be used potentially as a functional supplement to assist cancer radiotherapy patients.
Are Self-Driving Vehicles Ready to Launch? An Insight into Steering Control in Autonomous Self-Driving Vehicles
Authors: Rasib Marya , Butt Muhammad Atif , Khalid Shehzad , Abid Samia , Raiz Faisal , Jabbar Sohail , Han Kijun
Published: February 2021

In the last couple of years, academia-industry collaboration has demonstrated rapid advancements in the development of self-driving vehicles. Since it is evident that self-driving vehicles are going to reshape the traditional transportation systems in near future through enhancement in safe and smart mobility, motion control in self-driving vehicles while performing driving tasks in a dynamic road environment is still a challenging task. In this regard, we present a comprehensive study considering the evolution of steering control methods for self-driving vehicles. Initially, we discussed an insight into the traditional steering systems of the vehicles. To the best of our knowledge, currently, there is no taxonomy available, which elaborates steering control methods for self-driving vehicles. In this paper, we present a novel taxonomy including different steering control methods which are categorized into deterministic and heuristic steering control methods. Concurrently, the abovementioned techniques are critically reviewed elaborating their strengths and limitations. Based on the analysis, key challenges/research gaps in existing steering control methods along with the possible solutions have been briefly discussed to improve the effectiveness of the steering system of self-driving vehicles.
Generating Chaotic Series via Encryption Method in Fractional-Order Chua Systems
Authors: Gong Bo , Zhang Haodong , Wan Liguang
Published: February 2021

Fractional-order Chua systems have drawn wide attention in view of rich dynamic characteristics, e.g., chaos and hyperchaos. How to generate chaotic series via encryption method in fractional-order Chua systems is a difficult point all the while. In this paper, we derive several encryption methods in fractional-order Chua systems to generate chaotic series. As one of the most direct application, image encryption is also discussed by the presented methods.
To Delay Instantiation of a Smart Contract to Save Calculation Resources in IoT
Authors: Su Hong , Guo Bing , Shen Yan , Zhang Zhen , Qin Chaoxia
Published: February 2021

Smart contracts are required to be instantiated in the predeployed stage, which consumes computation resources from then on. It is a big waste in the blockchain whose nodes are composed of IoT devices, as those devices often have limited resources (such as limited power supplies or a limited number of processes to run). Meanwhile, IoT devices are heterogeneous and different smart contracts are required. If those smart contracts are instantiated previously, numerous meaningless addresses are required. In this paper, we propose to delay the instantiation of a smart contract when used and terminate it when not used, which is similar to the life cycle of a variable. Then, a new kind of variable (the wrapping variable) is used to hide details of the instantiation and the address. The smart contract is instantiated in the construction function of the wrapping variable, or even it is delayed to the time when there are requests for it. The smart contract terminates when the variable is out of its scope. Then, different instantiation methods are proposed. Finally, we perform the qualitative comparison between the proposed approach and the predeployment method, and it demonstrates that the proposed methods optimize the life cycle of the smart contract and save calculation resources.
A Novel Classified Ledger Framework for Data Flow Protection in AIoT Networks
Authors: Han Daoqi , Wu Songqi , Hu Zhuoer , Gao Hui , Liu Enjie , Lu Yueming
Published: February 2021

The edge computing node plays an important role in the evolution of the artificial intelligence-empowered Internet of things (AIoTs) that converge sensing, communication, and computing to enhance wireless ubiquitous connectivity, data acquisition, and analysis capabilities. With full connectivity, the issue of data security in the new cloud-edge-terminal network hierarchy of AIoTs comes to the fore, for which blockchain technology is considered as a potential solution. Nevertheless, existing schemes cannot be applied to the resource-constrained and heterogeneous IoTs. In this paper, we consider the blockchain design for the AIoTs and propose a novel classified ledger framework based on lightweight blockchain (CLF-LB) that separates and stores data rights at the source and enables a thorough data flow protection in the open and heterogeneous network environment of AIoT. In particular, CLF-LB divides the network into five functional layers for optimal adaptation to AIoTs applications, wherein an intelligent collaboration mechanism is also proposed to enhance the across-layer operation. Unlike traditional full-function blockchain models, our framework includes novel technical modules, such as block regenesis, iterative reinforcement of proof-of-work, and efficient chain uploading via the system-on-chip system, which are carefully designed to fit the cloud-edge-terminal hierarchy in AIoTs networks. Comprehensive experimental results are provided to validate the advantages of the proposed CLF-LB, showing its potentials to address the secrecy issues of data storage and sharing in AIoTs networks.
Intelligent Data Mining of Computer‐Aided Extension Residential Building Design Based on Algorithm Library
Authors: Zhihui Gao , Guangtian Zou
Published: February 2021

In recent years, with the development of construction industry, more scientific, systematic, fast, and intelligent calculation methods are needed to coordinate urban development and fierce market competition, and mathematical algorithm library plays an important role in artificial intelligence. Therefore, the author uses computer mathematical algorithm and extension theory to study and analyze the residential building design and intelligent data mining. It is found that the research of the computer‐aided expression method of extension building planning is mainly the expression of the input and output system of extension building planning. It includes knowledge representation, system outline design, system flow, and interface expression based on the mathematical database.
Isolation and Characterization of Gram-Negative Bacterial Species from Pasteurized Dairy Products: Potential Risk to Consumer Health
Authors: Mariam Solomon H.
Published: February 2021

Pathogenic bacterial contaminants of dairy products cause economic and human life losses if not destroyed by pasteurization. Gram-negative bacteria are among such major contaminants. Contamination persists because of faulty pasteurization or occurs during postpasteurization processing. Many factors, including presence of asymptomatic healthy carriers, existence of broad-range host pathogens, and resistance of pathogens to ordinary disinfectants, hamper the control of such pathogens. Here, samples of pasteurized dairy products were subjected to enrichment/selective cultures to test for possible Salmonella contamination, followed by growth on/in various media to test for phenotypic properties and some virulence characteristics of isolates (catalase, urease, oxidase, gelatinase, etc.). Isolates were characterized by phenotypic and genotypic tests for identification and resistance to clinically relevant antibiotics, including disk diffusion and for β-lactamase production. All milk samples harbored Gram-negative bacilli, which constitute a public health hazard. All of the isolates exhibited intermediate-level or higher resistance to ≥2 clinically relevant antibiotics, while some were susceptible. None tested positive for phenotypic gelatin hydrolysis but exhibited alpha- or beta-hemolysis. Sequence alignments of 16S rRNA gene partial sequences suggested up to 99% sequence similarities to subspecies of Salmonella enterica. Most isolates were also β-lactamase producers, especially blaTEM. In conclusion, high contamination rates were found in all Ethiopian pasteurized milk samples. The reasons for this burden of contamination need to be elucidated for meaningful and targeted control. Larger studies are needed, specifically to reveal points of entry of potential pathogens into dairy products. Information from this work will help to address and control previously unrecognized health hazards associated with consumption of pasteurized dairy products.
Changes of Serum Zinc-α2-Glycoprotein Level and Analysis of Its Related Factors in Gestational Diabetes Mellitus
Authors: Xu Dongmei , You Jie , Chen Guixia , Su Hongli , Zhang Li , Cui Lingling , Li Zhonglei , Huang Guoling , Feng Caiying
Published: February 2021

Previous studies have discovered that zinc-α2-glycoprotein (ZAG) is related to insulin resistance and lipid metabolism. The aim of the study is to explore the change of serum ZAG and its related factors in gestational diabetes mellitus (GDM). Eighty newly diagnosed GDM patients were enrolled in the case group, and 80 normal pregnant women were selected as the control group. The differences of baseline data between the two groups were compared, and the change of serum ZAG level and its relationship with related indexes was analyzed. Compared to the control group, the level of serum ZAG in GDM women decreased (

P
<
0.001

). What is more, the serum ZAG level of overweight and normal subjects in two groups was also found to have statistical differences. The Pearson correlation (or Spearman correlation) analysis showed that serum ZAG level was negatively correlated with FPG, FINS, HOMA-IR, and TG (all

P
<
0.05

) and positively correlated with HDL (

P
<
0.05

). Multiple linear regression showed that HDL and HOMA-IR were independent factors of serum ZAG (

P
<
0.05

). The level of serum ZAG in patients with gestational diabetes mellitus decreased, and HDL and HOMA-IR are the influencing factors in the case group.
A Functional Taxonomy of Tumor Suppression in Oncogenic KRAS–Driven Lung Cancer
Authors: Cai Hongchen , Chew Su Kit , Li Chuan , Tsai Min K. , Andrejka Laura , Murray Christopher W. , Hughes Nicholas W. , Shuldiner Emily G. , Ashkin Emily L. , Tang Rui , Hung King L. , Chen Leo C. , Lee Shi Ya C. , Yousefi Maryam , Lin Wen-Yang , Kunder Christian A. , Cong Le , McFarland Christopher D. , Petrov Dmitri A. , Swanton Charles , Winslow Monte M.
Published: February 2021

Cancer genotyping has identified a large number of putative tumor suppressor genes. Carcinogenesis is a multistep process, but the importance and specific roles of many of these genes during tumor initiation, growth, and progression remain unknown. Here we use a multiplexed mouse model of oncogenic KRAS–driven lung cancer to quantify the impact of 48 known and putative tumor suppressor genes on diverse aspects of carcinogenesis at an unprecedented scale and resolution. We uncover many previously understudied functional tumor suppressors that constrain cancer in vivo. Inactivation of some genes substantially increased growth, whereas the inactivation of others increases tumor initiation and/or the emergence of exceptionally large tumors. These functional in vivo analyses revealed an unexpectedly complex landscape of tumor suppression that has implications for understanding cancer evolution, interpreting clinical cancer genome sequencing data, and directing approaches to limit tumor initiation and progression.

Significance:

Our high-throughput and high-resolution analysis of tumor suppression uncovered novel genetic determinants of oncogenic KRAS–driven lung cancer initiation, overall growth, and exceptional growth. This taxonomy is consistent with changing constraints during the life history of cancer and highlights the value of quantitative in vivo genetic analyses in autochthonous cancer models.

This article is highlighted in the In This Issue feature, p. 1601
DGKA Mediates Resistance to PD-1 Blockade
Authors: Fu Lingyi , Li Sen , Xiao WeiWei , Yu Kuai , Li Shuo , Yuan Sujing , Shen Jianfei , Dong Xingjun , Fang Ziqian , Zhang Jianeng , Chen Siyu , Li Wende , You Hua , Xia Xiaojun , Kang Tiebang , Tan Jing , Chen Gong , Yang An-Kui , Gao YuanHong , Zhou Penghui
Published: February 2021

Immunologic checkpoint blockade has been proven effective in a variety of malignancies. However, high rates of resistance have substantially hindered its clinical use. Understanding the underlying mechanisms may lead to new strategies for improving therapeutic efficacy. Although a number of signaling pathways have been shown to be associated with tumor cell–mediated resistance to immunotherapy, T cell–intrinsic resistant mechanisms remain elusive. Here, we demonstrated that diacylglycerol kinase alpha (Dgka) mediated T-cell dysfunction during anti–PD-1 therapy by exacerbating the exhaustion of reinvigorated tumor-specific T cells. Pharmacologic ablation of Dgka postponed T-cell exhaustion and delayed development of resistance to PD-1 blockade. Dgka inhibition also enhanced the efficacy of anti–PD-1 therapy. We further found that the expression of DGKA in cancer cells promoted tumor growth via the AKT signaling pathway, suggesting that DGKA might be a target in tumor cells as well. Together, these findings unveiled a molecular pathway mediating resistance to PD-1 blockade and provide a potential therapeutic strategy with combination immunotherapy.
KPT-330 Prevents Aortic Valve Calcification via a Novel C/EBPβ Signaling Pathway
Authors: Dutta Punashi , Kodigepalli Karthik M. , LaHaye Stephanie , Thompson J. Will , Rains Sarah , Nagel Casey , Thatcher Kaitlyn , Hinton Robert B. , Lincoln Joy
Published: February 2021

Rationale:

Calcific aortic valve disease (CAVD) affects >5.2 million people in the United States. The only effective treatment is surgery, and this comes with complications and no guarantee of long-term success.

Objective:

Outcomes from pharmacological initiatives remain unsubstantiated and, therefore, the aim of this study is to determine if repurposing a selective XPO1 (exportin-1) inhibitor drug (KPT-330) is beneficial in the treatment of CAVD.

Methods and Results:

We show that KPT-330 prevents, attenuates, and mitigates calcific nodule formation in heart valve interstitial cells in vitro and prevents CAVD in
Klotho
−/−
mice. Using RNA-sequencing and mass spectrometry, we show that KPT-330’s beneficial effect is mediated by inhibiting nuclear export of the C/EBPβ (transcription factor CCAAT/enhancing-binding protein) in valve interstitial cells, leading to repression of canonical Wnt signaling, in part, through activation of the Wnt antagonist
Axin1
, and a subsequent decrease in proosteogenic markers and cell viability.

Conclusions:

Our findings have met a critical need to discover alternative, pharmacological-based therapies in the treatment of CAVD.
Introducing Smart e-Trials into the UAE Judicial System
Authors: Al-Enizi Ziad Kh , Ghandour Ahmad
Published: February 2021

Electronic trials (e-trials) or the use of electronic means in remote litigation are of great importance at both national and international levels. Many countries have sought to take advantage and reap the benefits of electronic means in litigation by adopting laws regulating this area. The United Arab Emirates is one of the Arab countries that showed great interest in this matter and has passed laws regulating it. This study analyses the electronic court from the perspective of the UAE through a twofold inquiry: firstly, regarding the nature of electronic courts in the UAE and how they operate; and, secondly, regarding litigation before the electronic court and the associated procedures. The study ends with a summary and conclusions.
Appropriation and Its Consequences: Archaeology under Colonial Rule in Egypt and India
Authors: Ratnagar Shereen
Published: February 2021

The beginnings of archaeology in Egypt and in India are the subject of this paper. In both countries, antiquities were carried away by the powerful. Moreover, the hubris of the colonial powers ruling both countries made it inevitable that not only antiquities, but knowledge about the past, were appropriated in different ways. For modern Egyptians, the Pharaonic past was remote in culture and distant in time. The people themselves were until fairly recently prevented from learning the Pharaonic writing, once it was deciphered, by various ways and means. In contrast, in India the colonial administration relied on Indian scholars to teach British personnel the ancient languages, texts, and religion. In neither country was the history of the ancient period taught in schools until the foreign rulers had left. But Indian archaeology became involved in Indian identity and in the framing of the nation as Hindu, and thereby acquired an ugly twist. Self-identification in Egypt in the earlier twentieth century, on the other hand, was possibly more with the Arab world than with the pyramid builders.
Ancient Egypt and the Near East in World History
Authors: Van De Mieroop Marc
Published: February 2021

Ancient Egypt and the Near East are central to many histories that aim to look at the world in its entirety, mostly because they are the earliest cultures that are well-documented both with textual and material evidence. This article surveys how these studies use that evidence in the various ways the discipline of world or global history is practiced. Those include chronological narratives of human activities from prehistory up to today, investigations that consider the worlds in which the peoples of ancient Egypt and the Near East lived, and comparative studies that seek to explain how certain features of human society and culture came about. The final question it addresses is whether the people of ancient Egypt and the Near East had any interest in a global history themselves.
What Made a Peasantry: Theory and Historiography of Rural Labor in Byzantine Egypt
Authors: Tedesco Paolo
Published: February 2021

Modern discussions of rural labor in Byzantine Egypt (300–700 CE) have been bedevilled by disagreement over the definition of that concept. There are three main competing conceptualizations: (i) Rural labor has been defined in terms of serfdom as a parallel outcome to the emergence of “private” (or feudal) large landowners as opposed to the decline of “public powers”; (ii) Rural labor has been described as “free” since it was based on contractual arrangements (primarily, rent tenancy) and on the payment of a public levy to the state; and (iii) Rural labor has been characterized in terms of exploitation, that is, as the instrument through which landholders (both landowners and tenants) extracted unpaid wealth from the population of producers. Building on a vast literature, this essay seeks to clarify that while the notion of feudal serfdom does not find corroborations in the Byzantine sources, the contractual, tributary, and “exploitative” characterizations of labor were not mutually exclusive, but instead describe different aspects and possible developments of the employer-employee relationships.
From Tenochtitlán to Punt: When People Encounter the Distant and Unknown, a Cognitive Approach
Authors: Miniaci Gianluca
Published: February 2021

This article aims to analyse the behavioural response generated by people who came into contact with civilisations and places whose existence was previously unknown or only remotely registered in their collective knowledge. Three major cases have been taken into consideration: a.) the “discovery” of America during the sixteenth century CE when Europeans entered in contact with Aztecs, Cakchiquels, and Andeans; b.) the encounters with the civilisations in Tahiti and Hawaii during the eighteenth century CE, and c.) the ancient Egyptian arrival at Punt during the fifteenth century BCE under the reign of queen Hatshepsut. Although spatially and chronologically separated by thousands of miles and hundreds of years, in all of these cases the “encounterers” (i.e., the ones who were moving towards the unknown or distant and contemporaries who were writing their own history) tended to project a self-perceived supremacy over the encountered people, configured as a spontaneous feeling of their supremacy over the local population (hence a “counterfeit” emic notion). In all the above cases, the “encountering” event gave rise to the creation of an “apotheosis” myth, in which the encounterers were supposed to be seen, and believed in, as “gods coming from the sky.” Applying concepts from the cognitive science to these historical events, the article aims to scrutinize the mental categories that tended to generate such a belief of divine superiority projected in the vision of the Other. Rather than being marginalized as an episodic event, the formation of an apotheosis myth can be interpreted as part of a global process, which emerges in the human mind-frame, solicited by mental processes and in contact with a number of similar external outputs.
The Forest Sector in the 2030 EU Climate Policy Framework: Looking back to Assess Its Future
Authors: Böhling Kathrin , Todeschini Maria Fernanda Marques
Published: February 2021

From 2021 onwards, forests and forestry will for the first time contribute to the European Union’s climate action targets. The new Land Use, Land Use Change & Forestry (lulucf) Regulation commits Member States to achieve carbon neutrality on the basis of an EU-wide system. The system accounts for carbon sequestered and emitted from forests and other land uses like crop- and wetland. What looks like a significant step in the Union’s climate policy framework, however, leaves the large potential of Europe’s forest sector for climate mitigation untapped. The present article draws this conclusion from a comprehensive analysis of 67 documents related to decision-making on the lulucf Regulation. It reveals coalitional politics and the salience of the Commission’s behavior as key to explain the Regulation’s limited scope and concludes with assessing the future role of forests in the Union’s climate policy framework.