bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inducing high exo selectivity in Diels–Alder reaction by dimethylborane substituent: a DFT study
Authors: Taherinia Davood , Fattahi Alireza 
Published: December 2022

AbstractIn this work, the role of Lewis acid–base (LAB) interaction on the stereoselectivity of the Diels–Alder (DA) reaction has been studied by DFT in gas and solution (dichloromethane) phases. The calculations were performed at the B3LYP/6-311G++ (d, p) level. Two different series of DA reactions were investigated: (1)—three mono-substituted cyclopentadienes + dimethyl(vinyl)borane; (2)—five α,β-unsaturated carbonyl compounds + cyclopenta-2,4-dien-1-yldimethylborane. The reacting diene and dienophile pairs were chosen to restrict LAB interaction to the exo reaction pathway. It was found that in some of the examined cases, the favorable LAB interaction is so strong that it can lead to a completely exo-selective DA reaction. Furthermore, a novel multistep synthetic method was hypothesized for preparing exo cycloadduct with near 100% stereoselectivity. Our results can open up new avenues toward the rational design of exo-selective DA reactions for synthesizing novel bioorganic compounds.
Automated detection of GFAP-labeled astrocytes in micrographs using YOLOv5
Authors: Huang Yewen , Kruyer Anna , Syed Sarah , Kayasandik Cihan Bilge , Papadakis Manos , Labate Demetrio 
Published: December 2022

AbstractAstrocytes, a subtype of glial cells with a complex morphological structure, are active players in many aspects of the physiology of the central nervous system (CNS). However, due to their highly involved interaction with other cells in the CNS, made possible by their morphological complexity, the precise mechanisms regulating astrocyte function within the CNS are still poorly understood. This knowledge gap is also due to the current limitations of existing quantitative image analysis tools that are unable to detect and analyze images of astrocyte with sufficient accuracy and efficiency. To address this need, we introduce a new deep learning framework for the automated detection of GFAP-immunolabeled astrocytes in brightfield or fluorescent micrographs. A major novelty of our approach is the applications of YOLOv5, a sophisticated deep learning platform designed for object detection, that we customized to derive optimized classification models for the task of astrocyte detection. Extensive numerical experiments using multiple image datasets show that our method performs very competitively against both conventional and state-of-the-art methods, including the case of images where astrocytes are very dense. In the spirit of reproducible research, our numerical code and annotated data are released open source and freely available to the scientific community.
Pulsed laser-assisted additive manufacturing of Ti-6Al-4V for in-situ grain refinement
Authors: Yoon Hansol , Liu Peipei , Park Yejun , Choi Gwanghyo , Choi Pyuck-Pa , Sohn Hoon 
Published: December 2022

AbstractMetal additive manufacturing (AM) enables rapid customization of complex parts. However, it leads to forming of columnar grain structures which give the AM parts anisotropic properties. In this study, we propose a pulsed laser-assisted AM (PLAAM) technique for in-situ grain refinement of Ti-6Al-4V parts. A nanosecond pulsed laser was focused onto a melt pool to generate a favorable environment for the promotion of fine equiaxed grains. The PLAAM technique provided an average prior-β grain size of 549.6 μm, compared to that of 1297 μm provided by the conventional AM technique. Moreover, the maximum value of multiples of uniform distribution of the β phase decreased from 16 to 7.7 when using the PLAAM technique, which indicates a weakened crystallographic texture. These changes confirm that the proposed PLAAM technique promotes finer and more equiaxed prior-β grains. Furthermore, because the proposed technique is a non-contact technique, it can be applied to existing processes without adjusting tool paths.
Mechanical characteristics and stability analysis of surrounding rock reinforcement in rectangular roadway
Authors: Gu Shuan-Cheng , Wang Pan , Yang Chao-Fan 
Published: December 2022

AbstractThe stability of surrounding rock with bolt support depends on the stability within the reinforcement range. To understand the reinforcing mechanism of a rectangular roadway bolt fully and accurately, a quantitative method for evaluating the stability of the surrounding rock of a rectangular roadway must be developed. First, a roof beam model of a rectangular tunnel is established according to the deformation law of surrounding rock. Based on the elastic–plastic theory, the deflection calculation formula can be derived, and the ultimate load of the roof beam can be obtained under the plastic state without support. Second, based on the reinforcement effect of bolts, a model of a surrounding rock reinforcement body is established, the physical and mechanical properties of this body are deduced, and a method for evaluating the stability of surrounding rock is derived. Finally, by considering actual engineering cases, the theoretical calculation results of surrounding rock deformation are compared with the numerical simulation and field monitoring results. Moreover, the influence of different parameters of the bolt support on the mechanical characteristics and stability of reinforcement is investigated. The results show that the theoretical calculations approximate the numerical simulation and field monitoring values, thus verifying the rationality of the theory. The physical and mechanical properties and stability of the surrounding rock reinforcement body are considerably affected by changes in bolt length and spacing. The anchor design must apply the following principle: the bolt must either be long and sparsely spaced or short and densely spaced. The theory presented in this paper provides a relatively simple and fast quantitative calculation method for the study of the surrounding rock stability of bolt-supported rectangular roadways.
Variations in home range and core area of red-backed voles (Myodes regulus) in response to various ecological factors
Authors: Lee Jae-Kang , Eom Tae-Kyung , Lee Dong-Ho , Ko Hyeongyu , Rhim Shin-Jae 
Published: December 2022

AbstractThe characteristics of animal distribution are determined by interactions between the resource requirements of animals and ecological factors. This study sought to evaluate the effects of diverse ecological factors on the home range and core area of red-backed voles (Myodes regulus) in a natural deciduous forest located on Mt. Gariwang, Pyeongchang and Jeongseon, South Korea. Our study focused on four types of ecological factors: topography, climate, cover, and demography. A total of 29 voles were radio-tracked from August to September 2021. Home range (95% utilization distribution; UD) and core area (50% UD) were calculated using the kernel density estimator (KDE). The home range (1659.49 m2) and core area (317.08 m2) were negatively affected by altitude. The lunar phase and temperature negatively and positively influenced the home range and core area, respectively. The home range was positively affected by understory vegetation, whereas the core area was not. The core area increased within microhabitats with a high density of conspecific individuals, with males having a larger home range (2006.19 m2) and core area (375.40 m2) than females (1043.13 m2 and 213.39 m2, respectively). These findings provide a deeper understanding of the diverse ecological factors affecting the distributions of animals, especially small rodents.
Theoretical prediction of two-dimensional BC2X (X = N, P, As) monolayers: ab initio investigations
Authors: Bafekry A. , Naseri M. , Faraji M. , Fadlallah M. M. , Hoat D. M. , Jappor H. R. , Ghergherehchi M. , Gogova D. , Afarideh H. 
Published: December 2022

AbstractIn this work, novel two-dimensional BC$$_2$$

2

X (X = N, P, As) monolayers with X atoms out of the B–C plane, are predicted by means of the density functional theory. The structural, electronic, optical, photocatalytic and thermoelectric properties of the BC$$_2$$

2

X monolayers have been investigated. Stability evaluation of the BC$$_2$$

2

X single-layers is carried out by phonon dispersion, ab-initio molecular dynamics (AIMD) simulation, elastic stability, and cohesive energies study. The mechanical properties reveal all monolayers considered are stable and have brittle nature. The band structure calculations using the HSE06 functional reveal that the BC$$_2$$

2

N, BC$$_2$$

2

P and BC$$_2$$

2

As are semiconducting monolayers with indirect bandgaps of 2.68 eV, 1.77 eV and 1.21 eV, respectively. The absorption spectra demonstrate large absorption coefficients of the BC$$_2$$

2

X monolayers in the ultraviolet range of electromagnetic spectrum. Furthermore, we disclose the BC$$_2$$

2

N and BC$$_2$$

2

P monolayers are potentially good candidates for photocatalytic water splitting. The electrical conductivity of BC$$_2$$

2

X is very small and slightly increases by raising the temperature. Electron doping may yield greater electric productivity of the studied monolayers than hole doping, as indicated by the larger power factor in the n-doped region compared to the p-type region. These results suggest that BC$$_2$$

2

X (X = N, P, As) monolayers represent a new promising class of 2DMs for electronic, optical and energy conversion systems.
A molecular barcode and web-based data analysis tool to identify imported Plasmodium vivax malaria
Authors: Trimarsanto Hidayat , Amato Roberto , Pearson Richard D. , Sutanto Edwin , Noviyanti Rintis , Trianty Leily , Marfurt Jutta , Pava Zuleima , Echeverry Diego F. , Lopera-Mesa Tatiana M. , Montenegro Lidia M. , Tobón-Castaño Alberto , Grigg Matthew J. , Barber Bridget , William Timothy , Anstey Nicholas M. , Getachew Sisay , Petros Beyene , Aseffa Abraham , Assefa Ashenafi , Rahim Awab G. , Chau Nguyen H. , Hien Tran T. , Alam Mohammad S. , Khan Wasif A. , Ley Benedikt , Thriemer Kamala , Wangchuck Sonam , Hamedi Yaghoob , Adam Ishag , Liu Yaobao , Gao Qi , Sriprawat Kanlaya , Ferreira Marcelo U. , Laman Moses , Barry Alyssa , Mueller Ivo , Lacerda Marcus V. G. , Llanos-Cuentas Alejandro , Krudsood Srivicha , Lon Chanthap , Mohammed Rezika , Yilma Daniel , Pereira Dhelio B. , Espino Fe E. J. , Chu Cindy S. , Vélez Iván D. , Namaik-larp Chayadol , Villegas Maria F. , Green Justin A. , Koh Gavin , Rayner Julian C. , Drury Eleanor , Gonçalves Sónia , Simpson Victoria , Miotto Olivo , Miles Alistair , White Nicholas J. , Nosten Francois , Kwiatkowski Dominic P. , Price Ric N. , Auburn Sarah 
Published: December 2022

AbstractTraditionally, patient travel history has been used to distinguish imported from autochthonous malaria cases, but the dormant liver stages of Plasmodium vivax confound this approach. Molecular tools offer an alternative method to identify, and map imported cases. Using machine learning approaches incorporating hierarchical fixation index and decision tree analyses applied to 799 P. vivax genomes from 21 countries, we identified 33-SNP, 50-SNP and 55-SNP barcodes (GEO33, GEO50 and GEO55), with high capacity to predict the infection’s country of origin. The Matthews correlation coefficient (MCC) for an existing, commonly applied 38-SNP barcode (BR38) exceeded 0.80 in 62% countries. The GEO panels outperformed BR38, with median MCCs > 0.80 in 90% countries at GEO33, and 95% at GEO50 and GEO55. An online, open-access, likelihood-based classifier framework was established to support data analysis (vivaxGEN-geo). The SNP selection and classifier methods can be readily amended for other use cases to support malaria control programs.
Challenges and strategies toward long-term stability of lead-free tin-based perovskite solar cells
Authors: Aktas Ece , Rajamanickam Nagalingam , Pascual Jorge , Hu Shuaifeng , Aldamasy Mahmoud H. , Di Girolamo Diego , Li Wenhui , Nasti Giuseppe , Martínez-Ferrero Eugenia , Wakamiya Atsushi , Palomares Emilio , Abate Antonio 
Published: December 2022

AbstractDue to their outstanding optoelectronic properties, lead-based halide perovskite materials have been applied as efficient photoactive materials in solution-processed solar cells. Current record efficiencies offer the promise to surpass those of silicon solar cells. However, uncertainty about the potential toxicity of lead-based halide perovskite materials and their facile dissolution in water requires a search for new alternative perovskite-like materials. Thanks to the foresight of scientists and their experience in lead-based halide perovskite preparation, remarkable results have been obtained in a short period of time using lead-free perovskite compositions. However, the lower solar-to-energy conversion efficiency and long-term stability issues are serious drawbacks that hinder the potential progression of these materials. Here, we review and analyse strategies in the literature and the most promising solutions to identify the factors that limit the power conversion efficiency and long-term stability of lead-free tin-based perovskite solar cells. In the light of the current state-of-the-art, we offer perspectives for further developing these promising materials.
Sulfur fertiliser use in the Midwestern US increases as atmospheric sulfur deposition declines with improved air quality
Authors: Hinckley Eve-Lyn S. , Driscoll Charles T. 
Published: December 2022

AbstractSulfur, as an essential nutrient for plant growth, has increasingly been used in fertiliser applications for many crops. This increase is coincident with declines in atmospheric sulfur deposition in response to air quality improvements in the United States and Europe. Here, we evaluate trends in sulfur fertiliser sales by mass, as a proxy for fertiliser applications, and estimate total atmospheric sulfur deposition across the Midwestern United States. Crop acreage, yield and sulfur fertiliser application substantially increased between 1985 and 2015, coincident with declines in atmospheric sulfur deposition. The increase in sulfur fertiliser has outpaced the relative rate of change in other major nutrient fertilisers including nitrogen, phosphorus and potassium, by approximately 7-fold prior to 2009, and 29-fold after 2009. We suggest that there is a critical need to develop sulfur management tools that optimize fertiliser applications to maintain crop yields while minimizing the consequences of excess sulfur in the environment.
Investigating healthcare worker mobility and patient contacts within a UK hospital during the COVID-19 pandemic
Authors: Wilson-Aggarwal Jared K. , Gotts Nick , Wong Wai Keong , Liddington Chris , Knight Simon , Spyer Moira J. , Houlihan Catherine F. , Nastouli Eleni , Manley Ed 
Published: December 2022

Abstract
Background
Insights into behaviours relevant to the transmission of infections are extremely valuable for epidemiological investigations. Healthcare worker (HCW) mobility and patient contacts within the hospital can contribute to nosocomial outbreaks, yet data on these behaviours are often limited.

Methods
Using electronic medical records and door access logs from a London teaching hospital during the COVID-19 pandemic, we derive indicators for HCW mobility and patient contacts at an aggregate level. We assess the spatial-temporal variations in HCW behaviour and, to demonstrate the utility of these behavioural markers, investigate changes in the indirect connectivity of patients (resulting from shared contacts with HCWs) and spatial connectivity of floors (owing to the movements of HCWs).

Results
Fluctuations in HCW mobility and patient contacts were identified during the pandemic, with the most prominent changes in behaviour on floors handling the majority of COVID-19 patients. The connectivity between floors was disrupted by the pandemic and, while this stabilised after the first wave, the interconnectivity of COVID-19 and non-COVID-19 wards always featured. Daily rates of indirect contact between patients provided evidence for reactive staff cohorting in response to the number of COVID-19 patients in the hospital.

Conclusions
Routinely collected electronic records in the healthcare environment provide a means to rapidly assess and investigate behaviour change in the HCW population, and can support evidence based infection prevention and control activities. Integrating frameworks like ours into routine practice will empower decision makers and improve pandemic preparedness by providing tools to help curtail nosocomial outbreaks of communicable diseases.
The quest for unligated oxaphosphiranes with phosphorus in different coordination numbers
Authors: Faßbender Jan , Volk Niklas , García Alcaraz Antonio , Balasubramaniam Selvakumar , Espinosa Ferao Arturo , Streubel Rainer 
Published: December 2022

The first oxaphosphirane I has been synthesized. Reactions with borane (II) and oxidizing reagents (II, III) are reported, together with theoretical studies providing insight into ring strain energy, oxidation pathways and ring isomerization.
The WISSH quasars project
Authors: Saccheo I. , Bongiorno A. , Piconcelli E. , Testa V. , Bischetti M. , Bisogni S. , Bruni G. , Cresci G. , Feruglio C. , Fiore F. , Grazian A. , Luminari A. , Lusso E. , Mainieri V. , Maiolino R. , Marconi A. , Ricci F. , Tombesi F. , Travascio A. , Vietri G. , Vignali C. , Zappacosta L. , La Franca F. 
Published: December 2022

Context. Hyperluminous quasi-stellar objects (QSOs) are ideal laboratories to investigate active galactic nucleus (AGN) feedback mechanisms. Their formidable energy release causes powerful winds at all scales, and thus the maximum feedback is expected.
Aims. Our aim is to derive the mean spectral energy distribution (SED) of a sample of 85 WISE-SDSS selected hyperluminous (WISSH) quasars. Since the SED provides a direct way to investigate the AGN structure, our goal is to understand if quasars at the bright end of the luminosity function have peculiar properties compared to the bulk of the QSO population.
Methods. We collected all the available photometry, from X-rays to the far-infrared (FIR); each WISSH quasar is observed in at least 12 different bands. We then built a mean intrinsic SED after correcting for the dust extinction, absorption and emission lines, and intergalactic medium absorption. We also derived bolometric, IR band, and monochromatic luminosities together with bolometric corrections at λ = 5100 Å and 3 μm. We define a new relation for the 3 μm bolometric correction.
Results. We find that the mean SED of hyperluminous WISSH QSOs shows some differences compared to that of less luminous sources (i.e., a lower X-ray emission and a near- and mid-IR excess which can be explained assuming a larger dust contribution. WISSH QSOs have stronger emission from both warm (T ∼ 500 − 600 K) and very hot (T ≥ 1000 K) dust, the latter being responsible for shifting the typical dip of the AGN SED from 1.3 μm to 1.1 μm. We also derived the mean SEDs of two subsamples created based on their spectral features (presence of broad absorption lines and equivalent width of CIV line). We confirm that broad absorption lines (BALs) are X-ray weak and that they have a reddened UV-optical continuum. We also find that BALs tend to have stronger emission from the hot dust component. For sources with a weaker CIV line, our main result is the confirmation of their lower X-ray emission. By populating the LIR vs. z diagram proposed by Symeonidis & Page (MNRAS, 503, 3992), we found that ∼90% of WISSH QSOs with z ≥ 3.5 have their FIR emission dominated by star-forming activity.
Conclusions. This analysis suggests that hyperluminous QSOs have a peculiar SED compared to less luminous objects. It is therefore critical to use SED templates constructed exclusively from very bright quasar samples (such as this one) when dealing with particularly luminous sources, such as high-redshift QSOs.
The Short Neck: Challenges and Techniques
Authors: Auersvald Luiz A. , Auersvald André 
Published: December 2022

AbstractEstablishing a pleasant cervical contour in short-neck patients is of one the most difficult challenges for a facial plastic surgeon. Subplatysmal volume reduction, platysma tightening, and skin distribution adequately coupled with the middle third facelift are the pillars of the surgical approach. Additionally, treating the small chin, which is frequently observed in these patients, improves the overall result. In this paper, an objective method to define short-neck patients is offered. The applied surgical anatomy of the neck is revised. Innovative strategies to treat the supra and infrahyoid subplatysmal structures are presented, including the sternohyoid muscles plicature and the use of the interplatysmal/subplatysmal fat flap. A novel chin augmentation technique, using a subperiosteal en bloc fat graft is also introduced. A modified deep plane approach is described, including a continuous suture of the middle third fasciocutaneous flap. A combined lateral platysma tensioning with the sternocleidomastoid rejuvenation is demonstrated. Lastly, the hemostatic net is revisited as a critical approach to resolve the defying skin accommodation.
High SMAS Facelift: Combined Single Flap Lifting of the Midface, Cheek, and Jawline
Authors: Marten Timothy , Elyassnia Dino 
Published: December 2022

AbstractThe traditional deep plane and “low” cheek superficial musculoaponeurotic system (SMAS) flaps elevated below the zygomatic arch suffer the drawback that they cannot, by design, exert an effect on tissues of the midface and infra-orbital region. Traditional deep plane and low designs target the lower cheek and jowl only and produce no improvement in the upper anterior cheek and “midface” area. Planning the flap “higher,” along the zygomatic arch, and extending the dissection medially in an “extended SMAS” fashion to release and mobilize midface tissue, overcomes this problem and allows a combined, simultaneous, single flap lifting of the jawline, cheek, and midface. An improved outcome is obtained in many patients and no separate midface lift procedure is needed.
Ovarian and uterine changes during the oestrous cycle in female dogs
Authors: Lindh Lena , Kowalewski Mariusz P. , Günzel-Apel Anne-Rose , Goericke-Pesch Sandra , Myllys Vesa , Schuler Gerhard , Dahlbom Merja , Lindeberg Heli , Peltoniemi Olli A. T. 
Published: December 2022

Context An accurate staging of sexual cycle is essential for the optimum timing of medical interventions. Aims Here, an updated insight into clinical, endocrinological and vagino-cytological parameters, and their correlation with histomorphology of ovarian and uterine tissue samples is presented. Methods Samples from 39 dogs were collected at various stages of the oestrous cycle: pro-oestrus (n = 8), oestrus (n = 12), dioestrus (n = 9) (luteal phase) and anoestrus (n = 10), according to clinical observations. Final allocation of samples was done after histomorphological evaluation of all tissues. Peripheral oestradiol-17ß (E2) and progesterone (P4) concentrations were measured, P4 by both chemiluminescent immunoassay (CLIA) and radioimmunoassay (RIA). Key results Differences were observed between determination of the stage of the oestrous cycle, either by clinical, endocrinological or histomorphological evaluation. Individuals considered to be in clinical and endocrinological oestrus, had entered the luteal phase according to histomorphology. P4 concentrations measured by two different assays differed, underlying the importance to understand that absolute P4 concentrations may deviate depending on the used assay. Comparison of E2 and P4 concentrations is suggested to be useful when defining the transition from early follicular phase to the time of ovulation. Conclusions and implications Based on parallel histomorphological observations, combined with clinical and endocrinological findings on the same individuals, the present study emphasises that an accurate classification of the stage of the cycle in female dogs based solely on clinical and endocrinological assessments can be difficult. The histomorphological findings presented herein provide new insights into the transitional phases between the different stages of the oestrous cycle in the dog.