bluuebunny/crossref_metadata_2025 huggingface dataset:
USING ACTIVE LEARNING IN HYBRID LEARNING ENVIRONMENTS
Authors: Demazière C
Published: February 2021

In this paper, an innovative pedagogical approach relying on flipped classroom and offered in a hybrid learning environment combining on-site and off-site attendees is proposed. The set-up is furthermore tested on two short courses offered at Chalmers University of Technology and analyzed using student course evaluation questionnaires. Several elements constitute the backbone of the courses. Such elements are either offered in an asynchronous fashion or in a synchronous fashion. The asynchronous elements are made of textbooks specifically written for the respective courses, pre-recorded short webcasts explaining the key concepts of the textbooks and on-line quizzes giving formative feedback to the students. Such elements should thus be studied by the students before attending the synchronous sessions. Because of the preparatory work made by the students, the synchronous sessions can focus on much more active forms of learning under the teacher’s supervision. The success of the pedagogical approach entirely depends on the contents of the synchronous sessions, which need to be carefully planned and designed so that they promote student learning. Although the hybrid learning environment gives rise to some additional challenges from a teacher’s perspective, it also gives much more flexibility in attracting students from remote locations, without compromising the learning experience.
SIMULATOR ASSISTED ENGINEERING – APPLICATIONS IN NUCLEAR ENGINEERING EDUCATION AT KHALIFA UNIVERSITY
Authors: Alkaabi Ahmed K. , Ali Mohamed , Yoon Ho Joon , Ashy Oussama
Published: February 2021

The Generic Pressurized Water Reactor (GPWR) simulator has been used in the Nuclear I&C Laboratory at Khalifa University (KU) since 2013 to improve student performance in nuclear engineering that is a multidisciplinary field involving nuclear reactor physics, thermodynamics, fluid mechanics, thermal hydraulics, radiation, etc. The simulator, developed by Western Service Corporation, has been integrated as a teaching and educational tool in different Engineering Programs at KU (Mechanical and Nuclear engineering). This lab is used in an undergraduate course where students apply the knowledge taught from different courses such as nuclear systems, fuel cycle, thermal hydraulics, safety principle, and control functions through a virtual operating NPP simulator. This real-time, full scope and high fidelity simulator allows to perform different operating conditions such as plant startups, shutdowns, and load maneuvers; as well as normal and abnormal plant transients, and critical scenarios and accidents. Since its installation in the Nuclear I&C Laboratory at KU in 2013, thirty students have benefited from this learning simulator. The main skills and learning outcomes expected to be achieved by students through the using of this tool are (i) ability to describe different NPP components and understand different process occurring in different subsystems, (ii) explain and apply safety principles and protective protocols, and (iii) analyze and interpret the plant behavior during transient operations and when severe accidents happen.
APPLICATION OF RECENT DEVELOPMENTS IN INTEGRAL DATA ASSIMILATION TO IN-DEPTH ANALYSIS OF UH1.2 EXPERIMENT AND TRANSPOSITION TO WHOLE PWR CORE
Authors: Palau J.-M. , Rizzo A. , Tamagno P. , De Saint Jean C.
Published: February 2021

Recent developments in the Integral Data Assimilation (IDA) methods within Bayesian framework have been achieved at CEA to tackle the problem of correlated experiments (through technological uncertainties) and neutron transport model numerical effects. Hence, reference Monte-Carlo and deterministic calculations (TRIPOLI4® and APOLLO3®) are used together to solve neutron transport equations and get the sensitivity profiles. Furthermore, the analysis of the mock-up experiments technological parameters is performed to get accurate uncertainties and correlations between the experiments (finally the covariance experimental matrix required for IDA). We apply here the IDA approach with a new, extend set of statistical indicators (Cook’s distance, Bayesian and Aikike Information criteria (BIC, AIC)) implemented in the nuclear physics CEA CONRAD code, to the integral experiments UH1.2 in reference and voided configurations (standard PWR fuel assembly in the EOLE mock-up reactor). The adjusted multigroup cross-sections and posterior covariances are compared by choosing different ingredients in the assimilation process. Finally, the investigated key neutron parameters; reactivity, reactivity worth (void effects) and fissions rates are transposed (with the same CONRAD code) to a standard PWR core. This in-depth analysis enables us to predict the residual uncertainties and biases due to the multigroup cross-section adjustments assessing at the same time the similarity of these integral experiments for the main PWR neutronic safety parameters. In addition, technological parameters uncertainties and their impact on Bayesian adjustment process are taken into account through a global experimental covariance matrix. We point out that the UH1.2 experiments bring relevant additional information to PWR keff calculations reducing significantly the posterior results but are less relevant for fission rate distribution in reference and voided configurations.
FISSION YIELD UNCERTAINTY PROPAGATION IN MULTI-PASS REFUELING PEBBLE-BED HTGR
Authors: Wang Yizhen , Cui Menglei , Guo Jiong , Li Fu
Published: February 2021

Multi-pass refueling scheme is a highlighted feature of pebble bed HTGR which spatially mixes the burnup calculation inside core. Such refueling scheme relate burnup calculation in one region of the core to others and thus affects the uncertainty propagation of nuclear data, e.g. fission product yield. In this work, thermal neutron induced U-235 fission product yield uncertainties are propagated in HTR-PM models with various refueling schemes in V.S.O.P. code. And the effect of multi-pass refueling scheme is studied. Bayesian method is applied to estimate the covariance of fission product yield based on ENDF/B-VII.1 fission yield sub-library. Uncertainty quantification is performed with stochastic sampling method and log-normal based correlated sampling method is used to generate reasonable and self-consistent fission product yield samples. The analyzed results indicate that multi-pass refueling scheme could affect the uncertainty propagation of reactor local responses.
QUANTIFICATION OF NUCLEAR DATA AND MANUFACTURING UNCERTAINTIES IN VERA
Authors: Sedota Christopher , Palmtag Scott
Published: February 2021

Uncertainty quantification (UQ) was performed using the Consortium for the Advanced Simulation of Light Water Reactors (CASL) multiphysics core simulator VERA. Typically, only nuclear data cross sections are considered when trying to obtain uncertainty information in reactor simulation applications. In this paper, uncertainty in both nuclear cross section data and fuel manufacturing processes is analyzed using VERA. Uncertainties due to cross sections was determined by generating one thousand perturbed cross section libraries using the cross section covariance data provided in the evaluated nuclear data library. Uncertainty due to manufacturing was also determined using stochastic sampling and VERA. The use of similar stochastic sampling techniques for the same problems allows for the direct comparison of uncertainty stemming from the two sources of uncertainty. Sample size is considered due to the potentially large computational cost of stochastic sampling techniques, as is demonstrated in a full core depletion. It was found that for the Pressurized Water Reactor (PWR) pincell case at Hot Zero Power (HZP), the standard deviation in the neutron multiplication factor produced by material uncertainty was 101 pcm, while the standard deviation in the neutron multiplication factor produced by cross section uncertainty was 730 pcm. While the uncertainty in neutron multiplication factor due to cross section uncertainty is larger than uncertainty due to manufacturing uncertainties, neglecting manufacturing uncertainties may be an unacceptable oversight in certain high-precision simulation applications.
A TOPOLOGY OPTIMIZATION PROCEDURE FOR ASSISTING THE DESIGN OF NUCLEAR COMPONENTS
Authors: Chabod Sébastien
Published: February 2021

In this paper, we show that a module implemented in the MCNP transport code to perform sensitivity analyses can be diverted to perform topology optimizations of nuclear equipment. Component design with this approach leads to sophisticated solutions that outperform their human-designed counterparts.
DEVELOPMENT OF A MODELING APPROACH TO ESTIMATE RADIATION FROM A SPENT FUEL ROD QUIVER
Authors: Elter Zs. , Mishra V. , Grape S. , Branger E. , Jansson P. , Balkeståhl L. Pöder , Hedberg M.
Published: February 2021

Before encapsulation of spent nuclear fuel in a geological repository, the fuels need to be verified for safeguards purposes. This requirement applies to all spent fuel assemblies, including those with properties or designs that are especially challenging to verify. One such example are quivers, a new type of containers used to hold damaged spent fuel rods. After placing damaged rods inside the quivers, they are sealed with a thick lid and the water is removed. The lid is thick enough to significantly reduce the amount of the gamma radiation penetrating through it, which can make safeguards verification from the top using gamma techniques difficult. Considering that the number of quivers at storage facilities is foreseen to increase in near future, studying the feasibility of verification is timely.

In this paper we make a feasibility study related to safeguards verification of quivers, aimed at investigating the gamma and neutron radiation field around a quiver designed by Westinghouse AB and filled with PWR fuel rods irradiated at the Swedish Ringhals site. A simplified geometry of the quiver and the detailed operational history of each rod are provided by Westinghouse and the reactor operator, respectively.

The nuclide inventory of the rods placed in the quiver and the emission source terms are calculated with ORIGEN-ARP. The radiation transport is modeled with the Serpent2 Monte Carlo code. The first objective is to assess the capability of the spent fuel attribute tester (SFAT) to verify the content for nuclear safeguards purposes. The results show that the thick quiver lid attenuates the gamma radiation, thereby making gamma radiation based verification from above the quiver difficult.
SUBCRITICALITY ESTIMATION BY VIRTUAL NEUTRON CAPTURE METHOD
Authors: Mitsuyasu Takeshi , Morimoto Yuichi
Published: February 2021

The criticality safety control technique is required for the fuel debris removal from the Fukushima Dai-Ichi Nuclear Power Station which experienced a severe accident. The subcriticality estimation is expected to be done with only limited information about the fuel debris while the primary containment vessel internal survey work is ongoing. The purpose of this study is to develop the subcriticality estimation method called the virtual neutron capture method. The neutrons from the surface of the fuel debris represent a major portion of detector counts. The method consists of two evaluations: the evaluation at the surface of the fuel debris for which the isotope compositions are known by fuel debris sampling and the evaluation at the region of the fuel debris for which these compositions are unknown. For the unknown composition region, the average isotope composition with arbitrary water content is given. The method surveys the relationship with the detector count and the neutron multiplication factor with any size of the unknown composition region and any ratio of the water content before the on-site evaluation. The method is verified by experiments done in the Kyoto University Critical Assembly. The method shows that the maximum difference from the reference neutron multiplication factor is 4.5 %dk. As a result, the virtual neutron capture method can be adopted to the subcriticality monitoring if the method includes the estimation margin of 4.5 %dk within the neutron multiplication factor range from 0.70 to 0.95.
WASTE CLASSIFICATION ASSESSMENT OF NUCLEAR STEELS FOR FUSION POWER APPLICATIONS
Authors: Bailey G.W. , Gilbert M.R. , Vilkhivskaya O
Published: February 2021

Fusion power is an attractive option for the world’s future energy needs. An important goal for fusion is to avoid the severe radioactive waste issues associated with nuclear fission. However, the neutrons produced in the fusion plasma reaction impinge on the surrounding reactor structure causing nuclear activation. It is hoped that activated material from fusion facilities can be disposed of as low level waste 50-100 years after operation ceases, but recent work suggests this may be difficult to achieve. This work presents inventory simulations for a number of potential fusion steels, for two neutron irradiation conditions typical of the DEMO reactor concept. The results are used to determine if the steels meet low level waste regulations, for a number of different international waste management systems. These results show that steels do not appear able to consistently meet low level waste requirements when exposed to near-plasma neutron fluxes. They have more success when exposed to lower fluxes, but traditional steels will still struggle to meet low level waste requirements in a fusion environment.
PERFORMANCE STUDY OF GLOBAL WEIGHT WINDOW GENERATOR BASED ON PARTICLE DENSITY UNIFORMITY
Authors: He Peng , Wu Bin , Hao Lijuan , Sun Guangyao , Li Bin , Fischer Ulrich
Published: February 2021

The variance reduction techniques are necessary for Monte Carlo calculations in which obtaining a detailed calculation result for a large and complex model is required. The GVR method named as global weight window generator (GWWG) was proposed by the FDS team. In this paper, two typical calculation examples, ISPRA-Fe benchmark in SINBAD (Shielding Integral Benchmark Archive Database) and TF Coils (Toroidal Field coils) of European HCPB DEMO (Helium Cooled Pebble Bed demonstration fusion plant), are used to study the performance of GWWG method. It can be seen from the calculation results that the GWWG method has a significant effect in accelerating the Monte Carlo calculation. Especially when the global convergence calculation results are needed, the acceleration effect (FOMG) can reach 105 or more. It proves that the GWWG method is an effective tool for deep-penetration simulations using Monte Carlo method.
NEUTRON NOISE SPECTRAL FEATURES OF SIMULATED MECHANICAL AND THERMAL-HYDRAULIC PERTURBATIONS IN A PWR CORE
Authors: Torres L.A , Chionis D. , Montalvo C. , Dokhane A. , García-Berrocal A.
Published: February 2021

KWU-PWR reactors (SIEMENS design) are commonly exhibiting high neutron noise levels that can lead to costly operational issues. Recent analysis seems to indicate that, coolant flow, temperature oscillations, and mechanical vibrations have a key impact on neutron noise phenomena. In order to advance in understanding this phenomenon, the transient nodal code SIMULATE-3K (S3K) has been already utilized to simulate scenarios with individual or combined types of perturbation sources: mechanical vibrations of fuel assemblies and thermal-hydraulic fluctuations at the core inlet. In this work, new simulations are performed with all the perturbations applied simultaneously. The simulated neutron detectors responses are then analyzed with noise analysis techniques. All the simulated spectral features of neutron noise are compared to those obtained from real plant data. Results show that the simulated neutron noise phenomenology behaves similarly to that obtained from real plant data by increasing the fluctuation amplitude in the inlet coolant flow in the S3K calculations.
ACCELERATION OF A 2-DIMENSIONAL, 2-ENERGY GROUP NEUTRON NOISE SOLVER BASED ON A DISCRETE ORDINATES METHOD IN THE FREQUENCY DOMAIN
Authors: Yi Huaiqian , Vinai Paolo , Demazière Christophe
Published: February 2021

The acceleration of the convergence rate is studied for a neutron transport solver to simulate 2-D, 2-energy-group neutron noise problems in the frequency domain. The Coarse Mesh Finite Difference (CMFD) method is compared to the Diffusion Synthetic Acceleration (DSA) method. Numerical tests are performed using heterogeneous system configurations with different boundary conditions. The CMFD scheme leads to a better convergence rate. The results also show that CMFD can accelerate neutron noise problems in a wide range of perturbation frequencies with almost equal efficiency. An unstable convergence behavior is nevertheless observed in problems with purely reflective boundary conditions. Stabilization techniques such as performing multiple transport sweeps, underrelaxing the flux update, and using the lpCMFD method are investigated and improvements can be obtained.
CORE SIM+ SIMULATIONS OF COLIBRI FUEL RODS OSCILLATION EXPERIMENTS AND COMPARISON WITH MEASUREMENTS
Authors: Mylonakis A. G. , Demazière C. , Vinai P. , Lamirand V. , Rais A. , Pakari O. , Frajtag P. , Godat D. , Hursin M. , Perret G. , Laureau A. , Fiorina C. , Pautz A.
Published: February 2021

At EPFL, the CROCUS reactor has been used to carry out experiments with vibrating fuel rods. The paper presents a first attempt to employ the measured data to validate CORE SIM+, a neutron noise solver developed at Chalmers University of Technology. For this purpose, the original experimental data are processed in order to extract the necessary information. In particular, detector recordings are scrutinized and detrended, and used to estimate CPSDs of detector pairs. These values are then compared with the ones derived from the CORE SIM+ simulations of the experiments. The main trend of the experimental data along with the values for some detectors are successfully reproduced by CORE SIM+. Further work is necessary on both the experimental and computational sides in order to improve the validation process.
INTELLIGENT TECHNIQUES FOR ANOMALY DETECTION IN NUCLEAR REACTORS
Authors: Ioannou George , Tagaris Thanos , Alexandridis Georgios , Stafylopatis Andreas
Published: February 2021

The safe operation of nuclear power plants is highly dependent on the ability of quickly and accurately identifying possible anomalies and perturbations in the reactor. Operational defects are primarily diagnosed by detectors that capture changes in the neutron flux, placed at various points inside and outside of the core. Neutron flux signals are subsequently analyzed with signal processing techniques in an effort to be better described (have their higher-order characteristics uncovered, locate transient events, etc). To this end, the application of intelligent techniques may be extremely beneficial, as it may assist and extend the current level of analysis. Besides, the combination of signal processing methodologies and machine learning techniques in the framework of nuclear power plant data is an emerging topic that has yet to show its full potential. In this context, the current contribution attempts at introducing intelligent approaches and more specifically, deep learning techniques, in neutron flux signal analysis for the identification of perturbations and other anomalies in the reactor core that may affect its operational capabilities. The obtained results of an initial stage of analysis on neutron flux signals captured at pressurized water reactors are encouraging, underlying the robustness and the potential of the proposed approach.
Effects of Isometric Biceps Exercise on Blood Pressure in Adults with Hypertension
Authors: Silva Paulo Henrique Medeiros , de Brito Leandro Campos , Cabral Ludmila Lucena Pereira , Farias-Junior Luiz Fernando , Browne Rodrigo Alberto Vieira , Vianna Lauro C. , Costa Eduardo Caldas
Published: February 2021

We investigated the acute effects of isometric biceps exercise on resting and ambulatory blood pressure in hypertensive adults. A total of 12 medicated hypertensive adults (aged 47±7 years; body mass index 27.2±2.7 kg/m2; resting blood pressure 123±12/74±6 mmHg) performed an isometric biceps exercise session (bilateral biceps exercise; 4×1 min at 30% of 1-RM, 2 min recovery) and a control session (without exercise) in a randomized order separated by a 7 to 10-day period. Resting blood pressure, heart rate, and heart rate variability indexes (SDNN, RMSSD, LF, HF, and LF/HF) were measured pre- and up to 30 min post-sessions. Next, ambulatory blood pressure was monitored during 22-hour post-sessions (awake and asleep periods). No significant changes were observed for resting blood pressure, heart rate, or heart rate variability indexes up to 30 min post-sessions (p>0.05). Furthermore, no significant differences were observed in average ambulatory blood pressure values in 22-hour (126±11/71±6 mmHg vs. 126±15/71±9 mmHg), awake (127±10/74±6 mmHg vs. 130±14/75±10 mmHg), and asleep (123±15/68±6 mmHg vs. 120±17/66±9 mmHg) periods between the control and isometric sessions, respectively (p>0.05). In conclusion, an isometric biceps exercise session does not elicit an acute antihypertensive effect in adults with hypertension, which suggests that its prescription to improve the acute BP control is limited.
Zervikofaziale Aktinomykose
Authors: Brosig Anja Maria , Hitzenbichler Florian , Ernst Benjamin , Köstler Josef , Bohr Christopher , Künzel Julian
Published: February 2021

Die Aktinomykose ist eine durch grampositive, fakultativ anaerobe Bakterien verursachte Infektionskrankheit, die sich in den meisten Fällen im zervikofazialen Bereich manifestiert und oft einen dentogenen Fokus aufweist. Das klinische Bild reicht vom akuten Abszessgeschehen bis zu chronisch fistulierenden Gewebeprozessen. Eine frühzeitige Diagnose und ein angemessenes therapeutisches Vorgehen mit einer Kombination aus ausgedehnter antibiotischer Behandlung und ggf. chirurgischer Sanierung sind für einen günstigen Krankheitsverlauf entscheidend. In diesem Artikel werden 5 Fälle von Aktinomyzeteninfektionen dargestellt, welche die Vielfalt der klinischen Erscheinungsbilder, die Problematik auf dem Weg zur richtigen Diagnose und mögliche Therapieverläufe illustrieren sollen.
Belonging and exclusion: the dark side of regional identity in Germany
Authors: Hildebrandt Achim , Trüdinger Eva-Maria
Published: February 2021

A collective regional identity is a favourable condition for the acceptance of majority decisions made at the regional level and for the delegation of competencies from the central to regional governments. Moreover, a regional identity can play an important role in times of global challenges. Regional attachment might generate a we-feeling and help individuals to cope better with a complex world. The same feeling, however, might also serve as a basis for exclusionary attitudes. In this article, we analyse regional identity at the Land level in Germany with data from the German General Social Survey. Our results show that regional identity is strong in both the eastern and western parts of the country, with people in the east, surprisingly, identifying with their respective Land slightly more than people in the west, even though the five eastern Länder were only established in 1990 after decades of centralist rule. Furthermore, the dark side of regional identity manifests itself only in eastern Germany, where a stronger regional identity tends to go hand in hand with a greater dislike of foreigners.
Thermal modeling of a parabolic trough collector in a quasi-steady state regime
Authors: Babikir Mahamat Hassane , Njomo Donatien , Barka Mahamat , Chara-Dackou Venant Sorel , Kondji Yvon Simplice , Khayal Mahamoud Youssouf
Published: February 2021

This manuscript deals with a quasi-steady regime thermal analysis of a solar parabolic trough collector in the climatic conditions of the city of N'Djamena located in a Sahelian region of the Chad Republic. The objective is to develop the solar electricity potential of N'Djamena and contribute to the development of renewable energies in the country. A one-dimensional numerical model was developed in a quasi-steady regime to simulate and analyze the thermal behavior of the system. The energy balance equations governing the thermal behavior of the collector are solved by the implicit finite difference method, while considering the variation of the solar radiation over time. Initially, the model was validated by experimental data existing in the literature. Excellent agreement is observed when comparing the numerical results to experimental data. The effect of various parameters, including the type of heat transfer fluids, wind speed, and mass flow rate of fluid, on the thermal performance of the parabolic trough solar collector in quasi-steady regime operation was observed. It is shown that the variation of wind speed has a very slight effect on the thermal performance of the collector. Four fluids (therminol 66, therminolV-P1, untreated water, and treated water) were simulated between 11:00 and 15:00 local time. Through the simulation of four fluids, it was shown that the energy efficiency of the collector when using oil is much better than with water.
Highly viscous fluid displaced by a chemically controlled reactive interface
Authors: Tafur Néstor , Escala Darío M. , Soto Ana , Muñuzuri Alberto P.
Published: February 2021

Displacement of a viscous fluid by a less viscous one is a challenging problem that usually involves the formation of interfacial digitations propagating into each one of the fluids, mixing them and preventing their normal displacement. We propose in this manuscript a protocol that is implemented via numerical simulation of the corresponding equations to improve the efficiency of the displacement. We consider a chemically active interface between the two chemically active fluids that produce a large viscosity interface that facilitates the process. All the relevant parameters of the mechanism are numerically analyzed aiming to optimize the efficiency of the method.
First principles investigation of charge transition levels in monoclinic, orthorhombic, tetragonal, and cubic crystallographic phases of HfO2
Authors: Alam Md Nur K , Clima S. , O'Sullivan B. J. , Kaczer B. , Pourtois G. , Heyns M. , Van Houdt J.
Published: February 2021

A first-principles study of native point defects in monoclinic, cubic, two different tetragonal, and five different orthorhombic phases of hafnia (HfO2) is presented. They include vacancy of tri-coordinated and tetra-coordinated oxygen, metal vacancy, interstitial metal, and interstitial oxygen. Defect formation energy, trap depth, and relaxation energy upon optical excitation of defects are listed. The trap depth of oxygen vacancies shows little variation among different phases compared to other defects. Results of the trap depth are compared against measurements and found to have reasonable agreement.
Review of Scientific Instruments New Products
Authors: Mandelis Andreas
Published: February 2021

In order to supplement manufacturers’ information, this department will welcome the submission by our readers of brief communications reporting measurements on the physical properties of materials which supersede earlier data or suggest new research applications.
Co-locating art and health: engaging civil society to create an enabling environment to respond to HIV in Indonesia
Authors: Newland Jamee , Lestari Dwi , Poedjanadi Mashoeroel Noor , Kelly-Hanku Angela
Published: February 2021

Background
This paper will report on the successful co-location of a community-based arts and sexual health project that aimed to engage, educate and create testing, treatment and care pathways at a co-located mobile sexual health clinic and community-controlled art gallery in Yogyakarta, Indonesia. Methods: Mixed methods were used to evaluate the project, including a visitor (n = 1181) and artist (n = 85) log book, a convenience audience survey (n = 231), and qualitative semi-structured interviews (n = 13) with artists and audience to explore the effect of arts-based activities on access to sexual health information and services, and stigma and discrimination. Results: In total, 85 artists curated five separate exhibitions that were attended by 1181 people, of which 62% were aged ≤24 years. Gallery attendance improved awareness and participatory and interactive engagement with sexual health information through a medium described as interesting, fun, cool, and unique. The co-located clinic facilitated informal pathways to sexual health services, including HIV/AIDS testing, treatment, and care. Importantly, the project created shared understandings and empathy that challenged stereotypes and myths, reducing stigmatising beliefs and practices. Conclusions: Arts-based programs are transformative and can be effectively implemented, replicated and scaled up in low-resource settings to create awareness and initiate for HIV prevention, testing, treatment, and care. Art-based health programs engages people in their communities, mobilises civil society, builds enabling environments to reduce stigma and discrimination and improves access to testing and prevention; essential features needed to end AIDS in Indonesia (and the Southeast Asia region) while improving the lives of those most vulnerable to infection.
Non-culmination in two Bantu languages
Authors: Persohn Bastian
Published: February 2021

This paper describes an exploratory approach to two related aspectual phenomena, non-culminating accomplishments and non-culminating construals of implied-result verbs, in the Bantu languages Xhosa and Nyakyusa. While documented for a diverse array of languages, leading to the identification of some cross-linguistic commonalities and axes of variation, these phenomena have so far not been studied for any continental African language. Both Xhosa and Nyakyusa license non-culminating accomplishments but differ regarding the felicity of such construals with different sub-types of accomplishments in relation to event progress, a decisive factor being that Nyakyusa possesses verbal partitive morphology. Concerning the non-culmination of implied-result verbs, both languages show such readings and support prior cross-linguistic findings that zero change readings are more readily available with agentive subjects. The data further point to the potential role of causative morphology as a parameter of variation to be considered in further comparative research on these verbs.
The Utility of Visual Appearance in Predicting the Composition of Street Opioids
Authors: McCrae Karen , Wood Evan , Lysyshyn Mark , Tobias Samuel , Wilson Dean , Arredondo Jaime , Ti Lianping
Published: February 2021

Background

With the emergence of unregulated fentanyl, people who use unregulated opioids are increasingly relying on appearance in an effort to ascertain the presence of fentanyl and level of drug potency. However, the utility of visual inspection to identify drug composition in the fentanyl era has not been assessed.

Methods

We assessed client expectation, appearance, and composition of street drug samples being presented for drug checking. Results of a visual screening test were compared to fentanyl immunoassay strip testing. We calculated sensitivity, specificity and likelihood ratios (LR) to assess the accuracy of the common assumption that samples with a “pebbles” appearance contain fentanyl.

Results

In total, of the 2502 unregulated opioid samples tested, 1820 (73.5%) appeared as “pebbles”, of which 1729 (95.0%) tested positive for fentanyl for a sensitivity of 75.9% (95% Confidence Interval [CI]: 74.2–77.6) and specificity of 59.4% (95%CI: 57.5–61.3). Although, the odds of samples containing fentanyl was 4.60 (95%CI: 3.47−6.11) times higher among pebbles samples compared to non-pebble samples, the positive LR for pebbles to contain fentanyl was only 1.87 (CI: 1.59–2.19). The negative LR was more useful at 0.41 (95% CI: 0.36−0.46).

Conclusions

A positive screening test for pebbles is not strongly enough associated to be used as a proxy for detecting fentanyl. While the absence of the appearance of pebbles does somewhat reduce the likelihood of fentanyl being present in a given sample, the high prevalence of fentanyl and fentanyl analogues in the drug supply and the risks of consumption are such that public health providers should routinely advise people who use unregulated opioids against solely relying on visual characteristics of drugs as a harm reduction strategy.
The use and Impact of Self-Monitoring on Substance use Outcomes: A Descriptive Systematic Review
Authors: Gass Julie C. , Funderburk Jennifer S. , Shepardson Robyn , Kosiba Jesse D. , Rodriguez Lauren , Maisto Stephen A.
Published: February 2021

Background

Self-Monitoring (SM), the act of observing ones’ own behavior, has been used in substance use treatment because SM may bring conscious awareness to automatized substance use behaviors. Empirical findings regarding SM's effectiveness are mixed. The aim of this study was to synthesize the literature for the efficacy of SM on substance use.

Method

A literature search was conducted using MEDLINE/PubMed.

Results

Out of 2,659 citations, 41 studies with 126 analyses were included. Among analyses from studies rated Moderate ( n = 24) or Strong ( n = 3) quality, SM was shown to have a helpful effect (e.g., reducing substance use) 29% of the time; to have no effect 63.0% of the time; and to be detrimental in 8.0% of analyses. SM's helpful effects were associated with methodological characteristics including longer monitoring and Phone/IVR and EMA/Computer methodologies compared to Paper/Pencil. SM was more helpful in non-treatment-seekers (35.0% of analyses showed SM to be helpful compared to 25.0% of analyses with treatment-seekers).

Conclusions

Results of this study suggest that SM, under certain circumstances, as the potential to be a low-cost, low-risk research and early intervention strategy for substance users.
Effect of Regular Kratom (Mitragyna Speciosa Korth.) Use on Quality of Life of People who use Kratom
Authors: Leong Bin Abdullah Mohammad Farris Iman , Yuvashnee Novline , Singh Darshan
Published: February 2021

Background

Kratom ( Mitragyna speciosa Korth.) is a traditional folk remedy used in Southeast Asia and is known to have a significant opioid-like effect. However, it is unknown whether kratom consumption can impair quality of life (QoL). This study aimed to examine the QoL of people who use kratom by comparing it with that of healthy non-kratom using controls and to determine the association between patterns of kratom use and QoL among people who use kratom.

Methods

200 respondents (100 subjects who use kratom and 100 healthy controls) were recruited for this cross-sectional study. The World Health Organization Quality of Life-BREF was administered to all the respondents to assess QoL, while the Kratom Dependence Scale (KDS) was used to assess the severity of kratom dependence among the subjects who use kratom.

Results

The physical health, psychological, and environment QoL scores of the subjects who use kratom were significantly lower than those of the healthy controls. Multiple linear regression analysis revealed greater KDS score and longer duration of kratom use were significant predictors of physical health QoL, while only greater KDS score significantly predicted psychological and environment QoL scores.

Conclusion

Prolonged kratom use and kratom dependence may negatively impact the QoL of people who use kratom, hence kratom addiction has to be treated adequately.
“Stories of starting”: Understanding the complex contexts of opioid misuse initiation
Authors: Spencer Noelle E. , Taubenberger Simone P , Roberto Raisa , Krishnamurti Lauren Sealy , Chang Judy C. , Hacker Karen
Published: February 2021

Background

The impacts of opioid use disorder and opioid-involved overdose are known, but less is known about the contexts in which people first misuse opioids, and the motivations for continued misuse.

Methods

In-depth interviews with 26 individuals in Allegheny County, Pennsylvania with current or past histories of opioid misuse were conducted. Narratives were analyzed to understand the circumstances and influences contributing to initial and continued misuse of opioids.

Results

Participants described social and familial contexts that normalized or accepted opioid misuse—this often included their own use of other illicit substances prior to initiating opioids. Participants also described initial use of opioids as related to efforts to cope with physical pain. They also described recognizing and then seeking psychological/emotional benefits from opioids. All three of these themes often overlapped and intersected in these stories of starting opioid misuse.

Conclusions

Opioid misuse stemmed from complex interacting influences involving coping with physical and psychological pain, perception that opioids are needed to feel “normal”, and acceptance or normalization of opioid use. This suggests a multi-pronged approach to both prevention and treatment are needed.
Extremes and extremal indices for level set observables on hyperbolic systems
*
Authors: Carney Meagan , Holland Mark , Nicol Matthew
Published: February 2021

Consider an ergodic measure preserving dynamical system (T, X, μ), and an observable

ϕ
:
X
→
R

. For the time series X

n
(x) = ϕ(T

n
(x)), we establish limit laws for the maximum process M

n
= max
k⩽n

X

k
in the case where ϕ is an observable maximized on a line segment, and (T, X, μ) is a hyperbolic dynamical system. Such observables arise naturally in weather and climate applications. We consider the extreme value laws and extremal indices for these observables on hyperbolic toral automorphisms, Sinai dispersing billiards and coupled expanding maps. In particular we obtain clustering and nontrivial extremal indices due to self intersection of submanifolds under iteration by the dynamics, not arising from any periodicity.
Charge trapping and recovery in ALD HfO2/β-Ga2O3 (010) MOS capacitors
Authors: Masten Hannah N , Phillips Jamie D , Peterson Rebecca L
Published: February 2021

The reliability of atomic layer deposited HfO2
β-Ga2O3 (010) MOS capacitors (MOSCAPs) was tested using constant voltage stress measurements. The HfO2/β-Ga2O3 MOSCAPs showed significant positive flatband voltage shifts (ΔV
fb) of up to +1.3 V after 4.3 × 103 s stress, likely due to electron trapping in the dielectric in border traps. Results indicate there may exist an electric field threshold between 0.98 and 1.23 MV cm−1 for electron trapping to occur in these MOSCAPs. Deep ultra-violet (DUV) illumination enables full recovery from the charge trapping. In contrast, HfO2/Si MOSCAPs do not recover under DUV illumination and exhibit smaller voltage shifts upon initial testing. We thus surmise that the type-II band alignment between HfO2 and β-Ga2O3 enables full recovery from stress-induced charge trapping via photogeneration of electron–hole pairs and hole transport across the negative valence band offset. This hypothesis is borne out by the observation of photo-current in the HfO2/β-Ga2O3 MOSCAPs when biased in depletion. In sum, HfO2/β-Ga2O3 MOS structures appear to be susceptible to flatband voltage shifts during stress bias due to the availability and accessibility of border traps. This work highlights the unique challenges in forming reliable ultra-wide band gap MOS devices, due to the significant role that border traps in the lower half of the insulator band gap play in bias stress response.
Ideal internal kink stability in presence of plasma flow and neoclassical toroidal viscosity due to energetic particles
Authors: Zhang N. , Liu Y.Q. , Yu D.L. , Hao G.Z. , Wang S. , Dong G.Q. , Liu L. , Shi Z.B. , Liu Yi
Published: February 2021

The influence of energetic particles (EPs) on the ideal internal kink mode, in rotating tokamak plasmas, is numerically investigated by simultaneously solving MHD-kinetic hybrid equations together with a toroidal momentum balance equation utilizing the MARS-Q code (Liu et al 2013 Phys. Plasmas
20 042503). The neoclassical toroidal viscous (NTV) torque, induced by precessional drift resonances of trapped energetic particles, acts as the momentum sink term to damp the plasma flow. Quasi-linear initial value simulations show local reduction of the flow amplitude and enhancement of the flow shear near the q = 1 rational surface (q is the safety factor) due to EP induced NTV. Both effects in turn destabilize the internal kink mode. These numerical findings are robust against the initial linear stability of internal kink, the initial plasma flow profile, as well as the equilibrium distribution model for EPs.
The role of El Niño in modulating the effects of deforestation in the Maritime Continent
Authors: Lee Ting-Hui , Lo Min-Hui
Published: February 2021

The deforestation rate in the Maritime Continent (MC) has been accelerating during the past several decades. Understanding the changes in local hydro-climatological cycles as deforestation takes place is essential because the MC is suffering from frequent and extreme droughts and fires, which often occur during the dry season and are more severe during El Niños. Therefore, this study explores how deforestation affects the hydrological cycle and precipitation in the MC during El Niños, focusing on the boreal autumn season and using the coupled atmosphere–land model simulations. It is found that the precipitation over the MC increases in the deforestation experiments, and the precipitation responses can be magnified during El Niño events. A strong subsidence anomaly associated with El Niño does not prevent enhanced convection associated with local deforestation. Instead, the subsidence reduces the cloud cover in the MC region during El Niño, which increases the incoming solar radiation and increases surface temperatures. Thus, a warmer environment induced by El Niño modulates the biogeophysical feedbacks associated with deforestation that also play a critical role in more substantial land surface warming. A warmer land surface induces a more unstable atmospheric environment associated with a tendency toward enhanced local convection and lateral moisture convergence. This study highlights how the different mean climate states may modulate the impact of local land-use changes on hydroclimatological cycles in the MC, and sheds light on the state of our knowledge of interactions between the local land surface and remote large-scale atmospheric circulations.
Air pollution and mental health: the moderator effect of health behaviors
Authors: Yang Zhiming , Song Qianhao , Li Jing , Zhang Yunquan , Yuan Xiao-Chen , Wang Weiqing , Yu Qi
Published: February 2021

Increasing incidents of regional pollution in China have threatened the well-being and physical and mental health of individuals. Therefore, the potential impact of air pollution on mental health must be assessed. This study examined the relationship between air pollution and mental health, as well as the regulatory effects of health behaviors. Air pollution was measured using the concentration of particulates with a diameter less than 2.5 μm (PM2.5), and mental health was measured using the Center for Epidemiologic Studies Depression (CES-D) scale. Using the China Family Panel Studies 2010 and 2014 data sets, the panel data regression model was employed to discuss the associations between air pollution and mental health and the interaction between air pollution and health behaviors on mental health. In total, 52 568 observations were collected. When the concentration of PM2.5 increased by 1 μg m−3, the CES-D scale scores decreased by 0.012 (95% CI: −0.021 to −0.003). Smoking was the only health behavior that made this effect more pronounced, its regulatory effect on the CES-D scale scores was −0.011 (95% CI: −0.021 to −0.002). The mental health of low-income individuals was also more vulnerable to the adverse effects of air pollution. This study highlights the potential impact of air pollution on mental health and the importance of health behaviors; it also provides suggestions for maintaining mental health and formulating policies based on changing air quality in the future.
Weak-force sensing in optomechanical systems with Kalman filtering
Authors: Gong Beili , Dong Daoyi , Cui Wei
Published: February 2021

We investigate the weak-force sensing in an optomechanical resonator by Kalman filter. By discretizing the continuous-time optomechanical system, the state of the resulting system is estimated by the unbiased minimum variance Kalman filter. Subsequently, the external stochastic force is estimated, provided that all noises in the system are white and Gaussian. Furthermore, the accuracy of force estimation, described by the mean squared error, is derived theoretically. The proposed algorithm is finally illustrated by comparing the theoretical accuracy with the numerical accuracy in an explicit example.
An early investigation of spatial correlation between Sentinel-2 based rice growth stages maps with satellite-based precipitation data to support digital agriculture development in Indonesia
Authors: Ramadhani F , Misnawati  , Syahbuddin H
Published: February 2021

Sustainability of rice production is a critical issue to ensure food security and needs to be monitored on time. Therefore, the online monitoring system using Sentinel-2 has been introduced to monitor rice fields in Indonesia. However, the system needs to be coupled with precipitation to improve user usage. In this study, the spatial correlation using Pearson’s correlation analysis and linear regression between the floods and the vegetative stages area of the rice monitoring maps and the precipitation data from CHIRPS was investigated. The analysis was conducted with the two datasets with 439 regencies in Indonesia on a monthly basis from December 2019 until May 2020. The result shows that 96 regencies have a highly positive correlation (r>0.6, p>0.05, n=6) with 57 regencies have a high R2 (R

2
>0.6). Also, there are 83 regencies has a profoundly negative correlation (r≤-0.6, p<0.05, n=6) with 32 regencies with high R2 (R

2
>0.6), On the other hand, there are 79 regencies have medium R2 (0.4≤R

2

<0.6), and 271 regencies have the lowest R2 value (R

2

≤0.4). These early-stage results show an opportunity to combine two datasets to produce early warning systems or recommended cropping calendar in a timely and accurate manner to the stakeholders or the farmers.
Characteristics and land potential for sugarcane development in Blitar Regency, East Java Province
Authors: Pratamaningsih M M , Mulyani A
Published: February 2021

The expansion of the sugarcane planting area needs to be supported by land resource data, such as characteristics and land suitability maps to optimize sugarcane growth and production. The study aimed to evaluate the land suitability, the dominant limiting factor, and the land availability for sugarcane development in Blitar Regency. Land suitability assessment was conducted by matching between land characteristics and sugarcane growth requirements. The study showed that the dominant soil in Blitar Regency was Kambisol Eutrik, having moderate to very deep soil depth, well-drained, and medium to a fine texture. The suitability classes of the land in the Blitar Regency were mostly marginally suitable (S3) covering of 87,529 ha (97.11%). This type of land has limiting factors, i.e., rooting condition (poorly drained and slightly coarse texture), nutrient retention (CEC <5 cmolc kg−1, pH >8.0), nutrient availability (very low K2O), and erosion hazard (slope 8 to 15%). The rest were classified as moderately suitable (S2) covering 2,604 ha (2.89%). The study implies that the extensification areas of sugarcane area in Blitar Regency around 21,876 ha could be expected to increase sugarcane productivity and sugar production.