bluuebunny/crossref_metadata_2025 huggingface dataset:
A vision of flexible dispatchable hybrid solar‐wind‐energy storage power plant
Authors: Bakhtvar Mostafa , Al Hinai Amer , El Moursi Mohamed S. , Albadi Mohammed H.
Published: June 2021

Dispatchable renewable generation is essential for 100% renewables power system. It is in the interest of both power system operators and customers since it reduces the need for flexibility and reserve. To this end, battery energy storage systems (BESS) are proposed for integration in the renewable power plant. This paper presents the optimal dispatch unit for a dispatchable hybrid solar‐wind power plant with BESS framework. It achieves optimal dispatchable renewable generation (from dispatchable hybrid renewable (solar‐wind) power plant with BESS, DHRB, operator perspective), subject to operational limits, by exploiting the synergy of wind and solar energy and combining it with storage capability of BESS using two different operation strategies, maximisation of revenues and maximisation of renewables harvesting. A continuous BESS degradation model is incorporated in the proposed rolling‐algorithm‐based‐optimal dispatch unit to improve the accuracy of results. The applicability of the proposed methodology and the performance of the operation strategies are demonstrated using a case study and the operation strategies are compared. Further, the effect of BESS size on its degradation and dispatchable power in a hybrid solar‐wind power plant with BESS are investigated through BESS lifetime. An indicative economic analysis is carried out to provide ground for the extra investment on and sizing of BESS for a dispatchable hybrid renewable power plant.
Variable structure interacting multiple model for highly aperiodic sensors with poor measurement precision
Authors: Lukeš Petr , Říha Milan
Published: June 2021

The issue of aircraft tracking using passive sensors with poor measurement precision and a variable update rate is investigated. First, the need for a time‐dependent Markov chain transition matrix for the Interacting Multiple Model (IMM) is thoroughly evaluated using simulation and real data from an experimental multilateration system. Three different methods for computing the time‐dependent matrix are compared, showing their superiority for highly aperiodic sensors. Second, the Variable Structure Interacting Multiple Model (VS‐IMM) for passive sensors with poor geometry is proposed, in which the mode set update is based on local dilution of precision or distance root mean square error. The performance of the estimator is compared with the IMM using real data. The VS‐IMM results in the best performance for areas of both high and low measurement precision.
Interface characteristics and formation mechanism of plasma arc welding-brazing aluminum alloy/ultrahigh-strength steel joint
Authors: Wu Di , Geng Wenhua , Li Hongmei , Wang Lei , Yu Ke , Sun Daqian
Published: June 2021

A butt welding-brazing joint of 5A06 aluminum alloy and DP1180 ultrahigh-strength steel was carried out by using plasma arc welding (PAW) with Al-Si welding wire. Interface characteristics, formation mechanism and mechanical properties of the joint were investigated. The results showed that the dissimilar joint contained bond zone, weld zone and Al/steel interface zone. During PAW, the inter-diffusion of Fe and Al and the interfacial reaction occurred, and the double-layer structure intemtallics (IMCs) composed of Fe4Al13 layer and Fe2Al5 layer were produced in the interface zone. The thickness and morphology of both IMC layers depended on different positions in the interface zone. The Fe2Al5 layer thickness decreased obviously and its morphology changed from continuous layer to discontinuous layer with the decrease of welding heat input. The average tensile strength of the joint was 88 MPa and the joint fractured at the Al/steel interface zone with the highest hardness (524 HV). The interface zone IMCs were the main factor of affecting the mechanical properties of aluminum alloy and ultrahigh-strength steel PAW joint.
Local asymptotic self-similarity for heavy tailed harmonizable fractional Lévy motions
Authors: Basse-O’Connor Andreas , Grønbæk Thorbjørn , Podolskij Mark
Published: June 2021

In this work we characterize the local asymptotic self-similarity of harmonizable fractional Lévy motions in the heavy tailed case. The corresponding tangent process is shown to be the harmonizable fractional stable motion. In addition, we provide sufficient conditions for existence of harmonizable fractional Lévy motions.
Prophylactic colectomy and rectal preservation in FAP: systematic endoscopic follow-up and adenoma destruction changes natural history of polyposis
Authors: Pasquer Arnaud , Benech Nicolas , Pioche Mathieu , Breton Antoine , Rivory Jerome , Vinet Olivier , Poncet Gilles , Saurin Jean Christophe
Published: June 2021

Background and study aims Prophylactic surgery of familial adenomatous polyposis (FAP) includes total colectomy with ileorectal anastomosis (IRA) to proctocolectomy with ileoanal anastomosis (IAA). Surgical guidelines rely on studies without systematic endoscopic follow-up and treatment. Our aim was to report our experience based on a different approach: therapeutic follow-up, comparing in this setting IRA and IAA in terms of oncological safety and quality of life.

Patients and methods Between January 1965 and November 2015, all patients who underwent prophylactic surgery for FAP with therapeutic endoscopic follow-up in Lyon University hospital: systematic endoscopic treatment of adenomas, were retrospectively and prospectively (since 2011) included.

Results A total of 296 patients were analyzed: 92 had proctocolectomy with IAA (31.1 %), 197 total colectomy with IRA (66.5 %), and seven abdominoperineal resections (2.4 %). Median follow-up was 17.1 years (range, 0–38.1). Incidence of secondary cancer (IR vs. IAA) was 6.1 % vs. 1.1 % (P = 0.06; 95 %CI 0.001–0.36). The 15-year cancer-free and overall survival (IR vs. IAA) were 99.5 % vs 100 % (P = 0.09) and 98.9 % vs. 98.8 % (P = 0.82), respectively. Postoperative morbidity occurred in 44 patients: 29 (14.7 %) in the IRA and 15 (16.3 %) in the IAA group (P = 0.72). The mean number of stools per day in the respective groups were 4.4 (2.5) vs. 5.5 (2.6) (P = 0.001). Fecal incontinence occurred in 14 patients (7.1 %) in the IRA vs. 16 (17.4 %) in the IAA group (P = 0.03).

Conclusions A combination of therapeutic endoscopic treatment and extended rectal preservation appears to be a safe alternative to ileoanal J-pouch anastomosis.
Effect of DDAVP on Platelet Activation and Platelet-Derived Microparticle Generation
Authors: Persyn Matthieu , Athanase Nicolas , Trossaërt Marc , Sigaud Marianne , Ternisien Catherine , Béné Marie C. , Fouassier Marc
Published: June 2021

Background The way by which 1-deamino-8-D-arginine vasopressin (DDAVP) acts on platelets remains unclear. Data from the literature tend to show that there is no definite effect on platelet activation, but recent work has suggested that a subtype of platelets, activated by the combined action of collagen and thrombin, was triggered by DDAVP. Moreover, platelet microparticles (PMPs), which have been shown to be procoagulant, have rarely been studied in this context. The goal of this study was to analyze the effects of DDAVP on PMPs' release through platelet activation.

Methods Fifteen out of 18 consecutive patients undergoing a therapeutic test with DDAVP were included. They were suffering from factor VIII deficiency or from von Willebrand disease. The expression of P-selectin and PAC-1 binding on platelets and the numbers of circulating PMPs were evaluated ex vivo before and after DDAVP infusion. Peripheral blood was collected on CTAD to limit artifactual platelet activation.

Results DDAVP induced a significant decrease of platelet counts and volume. Only small changes of P-selectin expression and PAC-1 binding were observed. Considering PMPs, two populations of patients could be defined, respectively, with (120%, n = 6) or without (21%, n = 7) an increase of PMPs after DDAVP. The decrease in platelet counts and volume remained significant in the group of responders.

Conclusion This study shows that DDAVP induces the generation/release of PMPs in some patients with factor VIII deficiency and von Willebrand disease 1 hour after DDAVP infusion.
Management of early gastric cancer meeting criteria for endoscopic resection: US population-based study
Authors: Barakat Mohamed , Ramai Daryl , Cheung Derrick , Abdelfatah Mohamed M. , Othman Mohamed O. , Carr-Locke David L. , Adler Douglas G.
Published: June 2021

Background and study aims The goal of this study was to assess surgical resection (SR) of early gastric cancer (EGC) fitting Japanese Gastric Cancer Association (JGCA) endoscopic resection (ER) criteria.

Patients and methods We analyzed EGC data from the national Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015.

Results A total of 2219 EGC cases were identified (1074 T1a and 1145 T1b). Of them, 409 met absolute criteria, 219 met expanded 1, 529 expanded 2, and 229 expanded 3. 259 lesions were treated endoscopically while 1007 were surgically resected (20.5 % vs 79.5 %, P = 0.0001). Temporal analysis showed that the frequency of ER steadily increased while SR proportionally decreased during the study period. Cox proportion regression analysis adjusting for confound variables (including age, gender, and race) showed no significant difference in the risk of mortality following either surgery or endoscopy.

Conclusions EGC can be safely treated with ER. However, EGC meeting JGCA ER criteria is largely treated with SR in the United States.
Homoeopathic Management of Conduct Disorder: A Case Series
Authors: Moorthi S. Karunakara , Radhika P.
Published: June 2021

Conduct disorder is a psychiatric syndrome occurring in childhood and adolescence, and is characterised by a long-standing pattern of violations of rules and antisocial behaviour. The aetiology of conduct disorder involves an interaction of genetic/constitutional, familial and social factors. Conduct disorder increases the risk of several public health problems, including violence, weapon use, substance abuse and dropping out of school. Thus, it is important to identify conduct disorder and begin intervention as early as possible.

Three cases of conduct disorder are presented here, which have been treated exclusively with homoeopathic medicines without any supportive therapies. The diagnosis and severity were assessed by Conduct Disorder Diagnostic Tool and the symptomatic assessment was done by using Conduct Disorder Rating Scale-Parent Version. Possible causal attribution of changes was explicitly depicted by Naranjo Criteria.

The initial outcome of homoeopathic treatment shows a positive role of homoeopathy as the cases are exclusively managed by homoeopathic medicine.
Dietary Treatment for NAFLD: New Clinical and Epidemiological Evidence and Updated Recommendations
Authors: Zelber-Sagi Shira
Published: June 2021

The key factor in preventing and treating nonalcoholic fatty liver disease (NAFLD) is a holistic lifestyle modification approach, encompassing diet based on healthy eating patterns of unprocessed foods, exercise, balanced drinking, and smoking habits. The Mediterranean diet and other healthy dietary patterns can reduce liver fat and may be related with lower disease progression. The type of diet should be tailored to the patient's cultural and personal preferences. Changing dietary composition without reducing caloric intake may offer an additional and sometimes more feasible alternative, so that the nutritional treatment incorporates, but is not focused on, weight reduction goals. The growing global consumption of ultra-processed foods, which is the polar opposite of the Mediterranean diet and its concept of home-based cooking, poses a great challenge in the prevention of NAFLD and probably hepatocellular carcinoma.

This review will cover the most updated clinical and epidemiological evidence for lifestyle treatment in NAFLD and provide practical treatment tools.
Beyond undocumented: Differences in the mental health of Latinx undocumented college students
Authors: Flores Morales Josefina , Garcia Yuliana
Published: June 2021

Undocumented college students face several threats to their well-being and mental health. Different social locations, including whether students have Deferred Action for Childhood Arrival (DACA) status, students’ gender, and family factors may shape students’ ability to be well. How these factors work together to shape mental health outcomes among undocumented Latinx college students is not well understood. This study examines several factors (demographic, familial, immigration, and socioeconomic factors) associated with anxiety scores of undocumented Latinx college students who participated in the UndocuScholars Project national online survey in 2014. We observe three notable findings: (1) DACA recipients report heightened levels of anxiety, (2) women with DACA status report higher levels of anxiety compared to non-DACAmented undocumented college students and men with DACA, and (3) students whose families motivate them report lower levels of anxiety. Latinx undocumented college students are not a monolith; demographic, family, and socioeconomic factors matter.
Maximum likelihood estimates of diffusion coefficients from single-particle tracking experiments
Authors: Bullerjahn Jakob Tómas , Hummer Gerhard
Published: June 2021

Single-molecule localization microscopy allows practitioners to locate and track labeled molecules in biological systems. When extracting diffusion coefficients from the resulting trajectories, it is common practice to perform a linear fit on mean-squared-displacement curves. However, this strategy is suboptimal and prone to errors. Recently, it was shown that the increments between the observed positions provide a good estimate for the diffusion coefficient, and their statistics are well-suited for likelihood-based analysis methods. Here, we revisit the problem of extracting diffusion coefficients from single-particle tracking experiments subject to static noise and dynamic motion blur using the principle of maximum likelihood. Taking advantage of an efficient real-space formulation, we extend the model to mixtures of subpopulations differing in their diffusion coefficients, which we estimate with the help of the expectation–maximization algorithm. This formulation naturally leads to a probabilistic assignment of trajectories to subpopulations. We employ the theory to analyze experimental tracking data that cannot be explained with a single diffusion coefficient. We test how well a dataset conforms to the assumptions of a diffusion model and determine the optimal number of subpopulations with the help of a quality factor of known analytical distribution. To facilitate use by practitioners, we provide a fast open-source implementation of the theory for the efficient analysis of multiple trajectories in arbitrary dimensions simultaneously.
Microcalorimeter measurement of x-ray spectra from a high-temperature magnetically confined plasma
Authors: Eckart M. E. , Beiersdorfer P. , Brown G. V. , Den Hartog D. J. , Hell N. , Kelley R. L. , Kilbourne C. A. , Magee E. W. , Mangoba A.-E. Y. , Nornberg M. D. , Porter F. S. , Reusch L. M. , Wallace J. P.
Published: June 2021

A NASA-built x-ray microcalorimeter spectrometer has been installed on the MST facility at the Wisconsin Plasma Physics Laboratory and has recorded x-ray photons emitted by impurity ions of aluminum in a majority deuterium plasma. Much of the x-ray microcalorimeter development has been driven by the needs of astrophysics missions, where imaging arrays with few-eV spectral resolution are required. The goal of our project is to adapt these single-photon-counting microcalorimeters for magnetic fusion energy research and demonstrate the value of such measurements for fusion science. Microcalorimeter spectrometers combine the best characteristics of the x-ray instrumentation currently available on fusion devices: high spectral resolution similar to an x-ray crystal spectrometer and the broadband coverage of an x-ray pulse height analysis system. Fusion experiments are increasingly employing high-Z plasma-facing components and require measurement of the concentration of all impurity ion species in the plasma. This diagnostic has the capability to satisfy this need for multi-species impurity ion data and will also contribute to measurements of impurity ion temperature and flow velocity, Zeff, and electron density. Here, we introduce x-ray microcalorimeter detectors and discuss the diagnostic capability for magnetic fusion energy experiments. We describe our experimental setup and spectrometer operation approach at MST, and we present the results from an initial measurement campaign.
Deep learning combined with IAST to screen thermodynamically feasible MOFs for adsorption-based separation of multiple binary mixtures
Authors: Anderson Ryther , Gómez-Gualdrón Diego A.
Published: June 2021

The structures of metal–organic frameworks (MOFs) can be tuned to reproducibly create adsorption properties that enable the use of these materials in fixed-adsorption beds for non-thermal separations. However, with millions of possible MOF structures, the challenge is to find the MOF with the best adsorption properties to separate a given mixture. Thus, computational, rather than experimental, screening is necessary to identify promising MOF structures that merit further examination, a process traditionally done using molecular simulation. However, even molecular simulation can become intractable when screening an expansive MOF database for their separation properties at more than a few composition, temperature, and pressure combinations. Here, we illustrate progress toward an alternative computational framework that can efficiently identify the highest-performing MOFs for separating various gas mixtures at a variety of conditions and at a fraction of the computational cost of molecular simulation. This framework uses a “multipurpose” multilayer perceptron (MLP) model that can predict single component adsorption of various small adsorbates, which, upon coupling with ideal adsorbed solution theory (IAST), can predict binary adsorption for mixtures such as Xe/Kr, CH4/CH6, N2/CH4, and Ar/Kr at multiple compositions and pressures. For this MLP+IAST framework to work with sufficient accuracy, we found it critical for the MLP to make accurate predictions at low pressures (0.01–0.1 bar). After training a model with this capability, we found that MOFs in the 95th and 90th percentiles of separation performance determined from MLP+IAST calculations were 65% and 87%, respectively, the same as MOFs in the simulation-predicted 95th percentile across several mixtures at diverse conditions (on average). After validating our MLP+IAST framework, we used a clustering algorithm to identify “privileged” MOFs that are high performing for multiple separations at multiple conditions. As an example, we focused on MOFs that were high performing for the industrially relevant separations 80/20 Xe/Kr at 1 bar and 80/20 N2/CH4 at 5 bars. Finally, we used the MOF free energies (calculated on our entire database) to identify privileged MOFs that were also likely synthetically accessible, at least from a thermodynamic perspective.
Machine-learning accelerated geometry optimization in molecular simulation
Authors: Yang Yilin , Jiménez-Negrón Omar A. , Kitchin John R.
Published: June 2021

Geometry optimization is an important part of both computational materials and surface science because it is the path to finding ground state atomic structures and reaction pathways. These properties are used in the estimation of thermodynamic and kinetic properties of molecular and crystal structures. This process is slow at the quantum level of theory because it involves an iterative calculation of forces using quantum chemical codes such as density functional theory (DFT), which are computationally expensive and which limit the speed of the optimization algorithms. It would be highly advantageous to accelerate this process because then one could do either the same amount of work in less time or more work in the same time. In this work, we provide a neural network (NN) ensemble based active learning method to accelerate the local geometry optimization for multiple configurations simultaneously. We illustrate the acceleration on several case studies including bare metal surfaces, surfaces with adsorbates, and nudged elastic band for two reactions. In all cases, the accelerated method requires fewer DFT calculations than the standard method. In addition, we provide an Atomic Simulation Environment (ASE)-optimizer Python package to make the usage of the NN ensemble active learning for geometry optimization easier.
Elucidating the mechanism behind the infrared spectral features and dynamics observed in the carbonyl stretch region of organic carbonates interacting with lithium ions
Authors: Fulfer Kristen D. , Galle Kankanamge Susith R. , Chen Xiaobing , Woodard Kaylee T. , Kuroda Daniel G.
Published: June 2021

Ultrafast infrared spectroscopy has become a very important tool for studying the structure and ultrafast dynamics in solution. In particular, it has been recently applied to investigate the molecular interactions and motions of lithium salts in organic carbonates. However, there has been a discrepancy in the molecular interpretation of the spectral features and dynamics derived from these spectroscopies. Hence, the mechanism behind spectral features appearing in the carbonyl stretching region was further investigated using linear and nonlinear spectroscopic tools and the co-solvent dilution strategy. Lithium perchlorate in a binary mixture of dimethyl carbonate (DMC) and tetrahydrofuran was used as part of the dilution strategy to identify the changes of the spectral features with the number of carbonates in the first solvation shell since both solvents have similar interaction energetics with the lithium ion. Experiments showed that more than one carbonate is always participating in the lithium ion solvation structures, even at the low concentration of DMC. Moreover, temperature-dependent study revealed that the exchange of the solvent molecules coordinating the lithium ion is not thermally accessible at room temperature. Furthermore, time-resolved IR experiments confirmed the presence of vibrationally coupled carbonyl stretches among coordinated DMC molecules and demonstrated that this process is significantly altered by limiting the number of carbonate molecules in the lithium ion solvation shell. Overall, the presented experimental findings strongly support the vibrational energy transfer as the mechanism behind the off-diagonal features appearing on the 2DIR spectra of solutions of lithium salt in organic carbonates.
Metal–insulator transition in RNiO3 (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er) induced by Li doping: A first-principles study
Authors: Cui Yuanyuan , Liu Xiao , Fan Wei , Ren Junsong , Gao Yanfeng
Published: June 2021

Rare earth nickelates (RNOs) have been extensively studied in recent decades because of the metal–insulator phase transition, which can be driven by chemical doping. In the present study, we apply the first-principles calculation to investigate the electronic structures, optical properties, and migration behaviors of Li-doped RNO. Results show that when the doping ratio reaches 100%, RNO changes from the metallic state into an insulating state, which is confirmed by the experimental report. Regarding the optical properties, the absorption coefficient and reflectivity decrease in Li-doped RNO over the entire range of visible and infrared light compared with pristine systems. The migration of Li along the [001] direction of RNO is studied and shows that as the radius of rare earth atoms decreases, the migration barrier generally shows a gradually decreasing trend. These findings may shed light on the application of RNO in electrochromic devices.
Mechanical rotation at low Reynolds number via reinforcement learning
Authors: Liu Yuexin , Zou Zonghao , Tsang Alan Cheng Hou , Pak On Shun , Young Y.-N.
Published: June 2021

There is growing interest in the development of artificial microscopic machines that can perform complex maneuvers like swimming microorganisms for potential biomedical applications. At the microscopic scales, the dominance of viscous over inertial forces imposes stringent constraints on locomotion. In the absence of inertia, Purcell first proposed an elegant way to generate net translation using kinematically irreversible motions [E. M. Purcell, “Life at low Reynolds number,” Am. J. Phys. 45, 3–11 (1977)]. In addition to net translation, a more recent prototype known as Purcell's “rotator” has been proposed in Dreyfus et al. [“Purcell's “rotator”: Mechanical rotation at low Reynolds number,” Eur. Phys. J. B 47, 161–164 (2005)] as a mechanical implementation of net rotation at low Reynolds numbers. These ingenious designs rely on knowledge of the surrounding environment and the physics of locomotion within the environment, which may be incomplete or unclear in more complex scenarios. More recently, reinforcement learning has been used as an alternative approach to enable a machine to learn effective locomotory gaits for net translation based on its interaction with the surroundings. In this work, we demonstrate the use of reinforcement learning to generate net mechanical rotation at low Reynolds numbers without requiring prior knowledge of locomotion. For a three-sphere configuration, the reinforcement learning recovers the strategy proposed by Dreyfus et al. As the number of spheres increases, multiple effective rotational strategies emerge from the learning process. However, given sufficiently long learning processes, all machines considered in this work converge to a single type of rotational policies that consist of traveling waves of actuation, suggesting its optimality of the strategy in generating net rotation at low Reynolds numbers.
Reconsidering the overdiagnosis of mild cognitive impairment for dementia prevention among adults aged ≥80 years
Authors: Maki Yohko
Published: June 2021

ABSTRACT A diagnosis at the stage of mild cognitive impairment (MCI) is encouraged to promote dementia prevention since intensive intervention during the mild stage is thought to be effective for dementia prevention. Many adults aged ≥80 years hope to prevent dementia; however, several issues should be considered regarding the diagnosis of MCI. First, the diagnosis of MCI is not clear-cut in actual medical practice, with the differentiation of MCI from normal states and mild dementia being blurred. Second, although MCI due to Alzheimer’s disease can be differentiated from MCI without pathological changes, interventions specific to MCI due to Alzheimer’s disease have not been developed. Third, the diagnosis of MCI can cause self-stigma, leading to psychological effects such as depression and anxiety for both the patients and their families, which can be risk factors for developing dementia for patients. In addition, medical resources are limited and diagnosing MCI is costly in medical human resources. Considering these issues, diagnosing MCI to promote dementia prevention should be viewed from the perspective of the individual patient’s interests, especially for those aged ≥80 years. The final decision regarding receiving a diagnosis or not should be the patient’s; therefore, it is necessary to increase patients’ health literacy, which requires medical professionals to provide them with appropriate evidence-based information. At the same time, it is important to provide psychological support to people who have been diagnosed.
Internal and external sexual consent during events that involved alcohol, cannabis, or both
Authors: Willis Malachi , Marcantonio Tiffany L. , Jozkowski Kristen N.
Published: June 2021

Background Substance-involved sexual activity is common. Even though people recognise that substance-related impairment can be a barrier to people’s ability to consent to sexual activity, most do not believe that substance use automatically negates sexual consent. We extended previous work on substance-related effects on internal and external consent by investigating sexual events that involved alcohol, cannabis, or both. Methods: For 28 days, 113 participants (MAge = 29.2 years, 57.5% women, 70.8% White) responded to three surveys per day on their personal devices. At time points when participants reported having engaged in partnered sexual activity, they were asked to report their alcohol use, cannabis use, internal consent feelings, and external consent communication. Results: Across 1189 partnered sexual events, 31.5% involved alcohol, cannabis, or both. Sexual events that involved combined use were associated with diminished feelings of safety/comfort and feelings that the sexual act was consensual, compared with events that involved neither substance. Greater levels of alcohol consumption were descriptively associated with lower ratings of internal sexual consent. Conclusions: We found that combined use of alcohol and cannabis may lead to lower internal sexual consent than using either substance alone – potentially due to greater levels of impairment associated with polysubstance use. Sexual health education programs should consider more nuanced approaches to teaching people how to navigate substance use and sexual consent.
Evaluation of the use of drones to monitor a diverse crocodylian assemblage in West Africa
Authors: Aubert Clément , Le Moguédec Gilles , Assio Cindy , Blatrix Rumsaïs , Ahizi Michel N’dédé , Hedegbetan Georges Codjo , Kpera Nathalie Gnanki , Lapeyre Vincent , Martin Damien , Labbé Pierrick , Shirley Matthew H.
Published: June 2021

Context West African crocodylian populations are declining and in need of conservation action. Surveys and other monitoring methods are critical components of crocodile conservation programs; however, surveys are often hindered by logistical, financial and detectability constraints. Increasingly used in wildlife monitoring programs, drones can enhance monitoring and conservation efficacy. Aims This study aimed to determine a standard drone crocodylian survey protocol and evaluate the drones as a tool to survey the diverse crocodylian assemblage of West Africa. Methods We surveyed crocodile populations in Benin, Côte d’Ivoire, and Niger in 2017 and 2018, by using the DJI Phantom 4 Pro drone and via traditional diurnal and nocturnal spotlight surveys. We used a series of test flights to first evaluate the impact of drones on crocodylian behaviour and determine standard flight parameters that optimise detectability. We then, consecutively, implemented the three survey methods at 23 sites to compare the efficacy of drones against traditional crocodylian survey methods. Key results Crocodylus suchus can be closely approached (>10 m altitude) and consumer-grade drones do not elicit flight responses in West African large mammals and birds at altitudes of >40–60 m. Altitude and other flight parameters did not affect detectability, because high-resolution photos allowed accurate counting. Observer experience, field conditions (e.g. wind, sun reflection), and site characteristics (e.g. vegetation, homogeneity) all significantly affected detectability. Drone-based crocodylian surveys should be implemented from 40 m altitude in the first third of the day. Comparing survey methods, drones performed better than did traditional diurnal surveys but worse than standard nocturnal spotlight counts. The latter not only detected more individuals, but also a greater size-class diversity. However, drone surveys provide advantages over traditional methods, including precise size estimation, less disturbance, and the ability to cover greater and more remote areas. Drone survey photos allow for repeatable and quantifiable habitat assessments, detection of encroachment and other illegal activities, and leave a permanent record. Conclusions Overall, drones offer a valuable and cost-effective alternative for surveying crocodylian populations with compelling secondary benefits, although they may not be suitable in all cases and for all species. Implications We propose a standardised and optimised protocol for drone-based crocodylian surveys that could be used for sustainable conservation programs of crocodylians in West Africa and globally.
A population genetic study of feral cats on Christmas Island
Authors: Koch K. , Pink C. , Hamilton N. , Algar D.
Published: June 2021

Feral and stray cats are a major threat for endemic species on Christmas Island and have been contributing to their decline. Cats were introduced to Christmas Island in 1888 and are now distributed across the whole island. We analysed the genetic population structure and diversity of feral and stray cats on Christmas Island to evaluate connectivity across the island and the possibility of discernible populations that could be targeted separately. Results indicate no differentiated population structure across the island, with cats facing no habitat obstacles to reduce their dispersal abilities across the island. We found high kin structure, suggesting individuals breeding successfully on the whole island. With the management of domestic and feral/stray cats since 2010, removal efforts targeting the whole island have successfully reduced the effective population size of feral/stray cats in the last five years. We suggest the use of various management techniques to facilitate future removal efforts, especially in areas on the island that are difficult to access.
Naming unrelated words predicts creativity
Authors: Olson Jay A. , Nahas Johnny , Chmoulevitch Denis , Cropper Simon J. , Webb Margaret E.
Published: June 2021

Significance

Many traditional measures of creativity require time-intensive and subjective scoring procedures. Their scores are relative to the specific sample, which makes multicultural or international assessments difficult. Our results show that a shorter and simpler task with automatic and objective scoring may be at least as reliable at measuring verbal creativity. This finding enables assessments across larger and more diverse samples with less bias.
Microstructural design for mechanical–optical multifunctionality in the exoskeleton of the flower beetle
Torynorrhina flammea
Authors: Jia Zian , Fernandes Matheus C. , Deng Zhifei , Yang Ting , Zhang Qiuting , Lethbridge Alfie , Yin Jie , Lee Jae-Hwang , Han Lin , Weaver James C. , Bertoldi Katia , Aizenberg Joanna , Kolle Mathias , Vukusic Pete , Li Ling
Published: June 2021

Significance

In the design of multifunctional materials, harnessing structural and compositional synergies while avoiding unnecessary trade-offs is critical in achieving high performance of all required functions. Biological material systems like the cuticles of many arthropods often fulfill multifunctionality through the intricate design of material structures, simultaneously achieving mechanical, optical, sensory, and other vital functionalities. A better understanding of the structural basis for multifunctionality and the functional synergies and trade-offs in biological materials could thus provide important insights for the design of bioinspired multifunctional materials. In this study, we demonstrate a concerted experimental, theoretical, and computational approach that uncovers the structure–mechanics–optics relationship of the beetle’s cuticle, opening avenues to investigate biological materials and design photonic materials with robust mechanical performance.
Engineering cellular metabolite transport for biosynthesis of computationally predicted tropane alkaloid derivatives in yeast
Authors: Srinivasan Prashanth , Smolke Christina D.
Published: June 2021

Significance

Our work highlights the importance of addressing metabolite transport limitations in parallel with strain and culture optimization for production of plant-derived medicines and derivatives in engineered microbes. We show that supervised classification strategies can outperform conventional approaches when searching plant transcriptomes for metabolite transporters. Our discovery of two vacuolar tropane alkaloid (TA) exporters provides insight into the spatial organization associated with biosynthesis of these molecules. We illustrate how differences in transporter specificity and mechanisms can be leveraged to control accumulation of pathway products in an enhanced yeast-based TA production platform. By engineering this platform for production of TA derivatives using enzymes evolved for alkaloid detoxification, we reveal sources of biocatalysts for expanding biosynthetic diversity in heterologous hosts.
Rtt105 promotes high-fidelity DNA replication and repair by regulating the single-stranded DNA-binding factor RPA
Authors: Wang Xuejie , Dong Yang , Zhao Xiaocong , Li Jinbao , Lee Jordan , Yan Zhenxin , Yang Shuangshuang , Wu Wenqiang , Hou Ximiao , Liu Guangxue , Zhang Yueyue , Song Lun , Cai Gang , Li Qing , Ira Grzegorz , Zhang Xinghua , Chen Xuefeng
Published: June 2021

Significance

Cells have evolved multiple mechanisms restraining the usage of lower-fidelity DNA repair pathways and polymerases. This work focuses on how deregulated Replication Protein A (RPA)–single-stranded DNA (ssDNA) assembly may impact the fidelity of genome duplication and repair. The absence of Rtt105 causes lower nuclear levels of RPA and impaired RPA-ssDNA assembly, resulting in increased replication errors with large deletions or duplications and elevated usage of the low-fidelity repair pathways. We show that this mechanism is likely conserved between yeast and humans. Thus, our work could provide insights into how human cells ensure high-fidelity DNA replication and repair. Furthermore, our study could potentially offer explanations for the genetic basis of some genome arrangements in human diseases.
The logic of categorisation in sport
Authors: Parry Jim , Martínková Irena
Published: June 2021

The aim of this paper is to examine the basis of eligibility rules in sport by exhibiting the logic of categorisation, with its associated ethical problems. We shall be concerned mainly with pre‐competition categories – age, sex, weight and dis/ability – because they are directly relevant to sports performance and are relatively stable inequalities. We shall prefer to use the term “categorisation”, although we mean by it just what others might mean by classification, to refer to divisions, classes, groups, etc. The paper argues that we have categories only because we consider it desirable to offer some groups protected status in order to enable and promote inclusion and fairness. This desirability condition determines eligibility. Only then do issues arise of which sub‐categories we should have, and how they are to be policed. There will always be categories in sport, as a minimum to protect athletes based on age groupings, from children to veterans. But since every categorisation brings its own problems, we need to ensure that we keep them balanced, so that sport can strive for maximum inclusion of different kinds of athletes, and maximum fairness. This requires us to step back from the many particular debates in order to rethink the logic of the whole categorisation process.
Wnt signaling establishes the microtubule polarity in neurons through regulation of Kinesin-13
Authors: Puri Dharmendra , Ponniah Keerthana , Biswas Kasturi , Basu Atrayee , Dey Swagata , Lundquist Erik A. , Ghosh-Roy Anindya
Published: June 2021

Neuronal polarization is facilitated by the formation of axons with parallel arrays of plus-end-out and dendrites with the nonuniform orientation of microtubules. In C. elegans, the posterior lateral microtubule (PLM) neuron is bipolar with its two processes growing along the anterior–posterior axis under the guidance of Wnt signaling. Here we found that loss of the Kinesin-13 family microtubule-depolymerizing enzyme KLP-7 led to the ectopic extension of axon-like processes from the PLM cell body. Live imaging of the microtubules and axonal transport revealed mixed polarity of the microtubules in the short posterior process, which is dependent on both KLP-7 and the minus-end binding protein PTRN-1. KLP-7 is positively regulated in the posterior process by planar cell polarity components of Wnt involving rho-1/rock to induce mixed polarity of microtubules, whereas it is negatively regulated in the anterior process by the unc-73/ced-10 cascade to establish a uniform microtubule polarity. Our work elucidates how evolutionarily conserved Wnt signaling establishes the microtubule polarity in neurons through Kinesin-13.
Assessment of tissue biochemical and optical scattering changes due to hypothermic organ preservation: a preliminary study in mouse organs
Authors: Saito Nogueira Marcelo , Raju Michael , Komolibus Katarzyna , Grygoryev Konstantin , Andersson-Engels Stefan
Published: June 2021

Clinical transplantation medicine currently faces a significant shortage of organ donors to supply the need of an increasingly aged population. Despite this, organs are still discarded due to graft stress induced by hypoxia or ischemia prior to procurement. Approaches to minimize donor organ discard include appropriate organ preservation and monitoring of organ function. Predominant organ preservation strategies involve hypothermia between 0 °C and 12 °C. In this study, we investigate the effect of temperature alone on tissue microstructural and biochemical parameters during cold preservation of mouse organs. To the best of our knowledge, this is the first study evaluating this cooling effect on multiple tissue parameters such as blood oxygenation, concentrations of blood, methemoglobin, water, lipid, and bile as well as scattering amplitude, Mie scattering power and fraction of Rayleigh scattering. These parameters were extracted by using diffuse reflectance spectroscopy spectral fitting at an extended wavelength range between 450 and 1590 nm and a Monte Carlo look-up table including a wide range of tissue optical properties compared to previous studies. Our findings can be used to understand biological processes undertaking cooling to propose new strategies involving optimized cold storage times and composition of organ preservation solutions for minimized cellular and tissue damage.
A first comparison of Kinetic Field Theory with Eulerian Standard Perturbation Theory
Authors: Kozlikin Elena , Lilow Robert , Fabis Felix , Bartelmann Matthias
Published: June 2021

We present a detailed comparison of the newly developed particle-based Kinetic Field Theory framework for cosmic large-scale structure formation with the established formalism of Eulerian Standard Perturbation Theory. We highlight the qualitative differences of both approaches by a comparative analysis of the respective equations of motion and implementation of initial conditions. A natural starting point for a first quantitative comparison is given by the non-interacting regime of free-streaming kinematics.
Our results suggest that Kinetic Field Theory contains a complete resummation of Standard Perturbation Theory in this regime.
We further show that the exact free-streaming solution of Kinetic Field Theory cannot be recovered in any finite order of Standard Perturbation Theory. Kinetic Field Theory
should therefore provide a better starting point for perturbative treatments of non-linear structure formation.
Scalar neutrino dark matter in the BLMSSM *
Authors: Zhang Ming-Jie , Zhao Shu-Min , Dong Xing-Xing , Yang Zhong-Jun , Feng Tai-Fu
Published: June 2021

The BLMSSM is an extension of the minimal supersymmetric standard model (MSSM). Its local gauge group is

. Supposing the lightest scalar neutrino is a dark matter candidate, we study the relic density and the spin independent cross section of sneutrino scattering off a nucleon. We calculate the numerical results in detail and find a suitable parameter space. The numerical discussion can confine the parameter space and provide a reference for dark matter research.
Global land use of diets in a small island community: a case study of Palau in the Pacific
Authors: Nakamura Shinichiro , Iida Akiko , Nakatani Jun , Shimizu Takafumi , Ono Yuya , Watanabe Satoshi , Noda Keigo , Kitalong Christopher
Published: June 2021

Modern dietary habits in communities are linked and are part of the global food supply chain. To achieve sustainable food production and consumption, communicating the impact associated with food production and dietary choices at community level to consumers is important. However, previous footprint studies have primarily focussed on food consumption at the national level and neglected community–level consumption activities. This study surveyed the diets of a small island community and linked the results with multi-region land footprint analysis in Ollei Village, Republic of Palau. The analysis was used to determine the extent to which the dietary lifestyles of communities depend on external land use through the global supply chain. We showed that the global food supply chain has reached this corner of the world, and the dietary habits of the community are already heavily dependent on processed and imported foods. The community and country are highly dependent on large land use in some major producer/exporting countries through the global food supply chain. In addition, the amount of external land used for food production exceeds the biocapacity of the agricultural land in the community and country. This study bridges the gap between community–level consumption activities and national-scale footprint analysis, and quantitatively assesses the impact of consumption activities at the community level on the global environment. The results and approach of this study could contribute to the development and implementation of vertically integrated food policies between the national and community level in Palau.
Coastal wetlands mitigate storm flooding and associated costs in estuaries
Authors: Fairchild Tom P , Bennett William G , Smith Greg , Day Brett , Skov Martin W , Möller Iris , Beaumont Nicola , Karunarathna Harshinie , Griffin John N
Published: June 2021

As storm-driven coastal flooding increases under climate change, wetlands such as saltmarshes are held as a nature-based solution. Yet evidence supporting wetlands’ storm protection role in estuaries—where both waves and upstream surge drive coastal flooding—remains scarce. Here we address this gap using numerical hydrodynamic models within eight contextually diverse estuaries, simulating storms of varying intensity and coupling flood predictions to damage valuation. Saltmarshes reduced flooding across all studied estuaries and particularly for the largest—100 year—storms, for which they mitigated average flood extents by 35% and damages by 37% ($8.4 M). Across all storm scenarios, wetlands delivered mean annual damage savings of $2.7 M per estuary, exceeding annualised values of better studied wetland services such as carbon storage. Spatial decomposition of processes revealed flood mitigation arose from both localised wave attenuation and estuary-scale surge attenuation, with the latter process dominating: mean flood reductions were 17% in the sheltered top third of estuaries, compared to 8% near wave-exposed estuary mouths. Saltmarshes therefore play a generalised role in mitigating storm flooding and associated costs in estuaries via multi-scale processes. Ecosystem service modelling must integrate processes operating across scales or risk grossly underestimating the value of nature-based solutions to the growing threat of storm-driven coastal flooding.