bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between 18F-FDG-PETCT-derived tumour metabolic activity, nutritional risk, body composition, systemic inflammation and survival in patients with lung cancer
Authors: Dolan Ross D. , Maclay John D. , Abbass Tanvir , Colville David , Buali Fatema , MacLeod Nicholas , McSorley Stephen T. , Horgan Paul G. , McMillan Donald C.
Published: November 2020

The aim of this study was to examine the relationship between PET-CT derived tumour glucose uptake as measured by maximum standard glucose uptake (SUVmax) and total lesion glycolysis (TLG), nutritional risk as measured by the malnutrition universal screening tool (MUST), CT derived body composition as measured by skeletal muscle index (SMI) and skeletal muscle radiodensity (SMD), the systemic inflammatory response as measured by the modified Glasgow prognostic score (mGPS) and the neutrophil to lymphocyte ratio (NLR) and survival in patients with lung cancer, treated with radiotherapy. In a retrospective cohort study, 119 patients were included in final analyses. The majority of patients were over 65 (86%), female (52%), had a performance status (ECOG-PS) of 0 or 1 (57%), were at nutritional risk (57%), were overweight (53%), had visceral obesity (62%), had a normal SMI (51%), had a low SMD (62%) and were systemically inflammed (mGPS 1/2, 51%). An elevated TLG was associated with sex (p < 0.05), TNM stage (p < 0.001), MUST (p < 0.01) and mGPS (p < 0.01). An elevated mGPS was associated with age (p < 0.05), NLR (p < 0.01), MUST (p < 0.01), and TLG (p < 0.01). On univariate survival analysis, TNM stage (p < 0.01), mGPS (p < 0.05), NLR (p < 0.01), MUST (p ≤ 0.001), Low SMD (p < 0.05), SUVmax (p ≤ 0.001) and TLG (p < 0.001) were associated with overall survival. On multivariate survival analysis MUST (HR: 1.49 95%CI 1.12–01.98 p < 0.01) and TLG (HR: 2.02 95%CI 1.34–3.04 p = 0.001) remained independently associated with survival. In conclusion, elevated tumour metabolic activity was associated with more advanced stage, greater nutritional risk, the systemic inflammatory response and poorer survival but not body composition analysis in patients with lung cancer. These results suggest that detrimental body composition is not directly determined by tumour metabolic activity but rather an ongoing systemic inflammatory response.
A robust method for automatic identification of femoral landmarks, axes, planes and bone coordinate systems using surface models
Authors: Fischer Maximilian C. M. , Grothues Sonja A. G. A. , Habor Juliana , de la Fuente Matías , Radermacher Klaus
Published: November 2020

The identification of femoral landmarks is a common procedure in multiple academic fields. Femoral bone coordinate systems are used particularly in orthopedics and biomechanics, and are defined by landmarks, axes and planes. A fully automatic detection overcomes the drawbacks of a labor-intensive manual identification. In this paper, a new automatic atlas- and a priori knowledge-based approach that processes femoral surface models, called the A&A method, was evaluated. The A&A method is divided in two stages. Firstly, a single atlas-based registration maps landmarks and areas from a template surface to the subject. In the second stage, landmarks, axes and planes that are used to construct several femoral bone coordinate systems are refined using a priori knowledge. Three common femoral coordinate systems are defined by the landmarks detected. The A&A method proved to be very robust against a variation of the spatial alignment of the surface models. The results of the A&A method and a manual identification were compared. No significant rotational differences existed for the bone coordinate system recommended by the International Society of Biomechanics. Minor significant differences of maximally 0.5° were observed for the two other coordinate systems. This might be clinically irrelevant, depending on the context of use and should, therefore, be evaluated by the potential user regarding the specific application. The entire source code of the A&A method and the data used in the study is open source and can be accessed via https://github.com/RWTHmediTEC/FemoralCoordinateSystem.
Clinical characteristics and predictors of mortality associated with COVID-19 in elderly patients from a long-term care facility
Authors: Trecarichi Enrico Maria , Mazzitelli Maria , Serapide Francesca , Pelle Maria Chiara , Tassone Bruno , Arrighi Eugenio , Perri Graziella , Fusco Paolo , Scaglione Vincenzo , Davoli Chiara , Lionello Rosaria , La Gamba Valentina , Marrazzo Giuseppina , Busceti Maria Teresa , Giudice Amerigo , Ricchio Marco , Cancelliere Anna , Lio Elena , Procopio Giada , Costanzo Francesco Saverio , Foti Daniela Patrizia , Matera Giovanni , Torti Carlo ,   IDTM UMG COVID-19 Group, Laganà Domenico , Petullà Maria , Bertucci Bernardo , Quirino Angela , Barreca Giorgio Settimo , Giancotti Aida , Gallo Luigia , Lamberti Angelo , Liberto Maria Carla , Marascio Nadia , De Francesco Adele Emanuela
Published: November 2020

Since December 2019, coronavirus disease 2019 (COVID-19) pandemic has spread from China all over the world and many COVID-19 outbreaks have been reported in long-term care facilities (LCTF). However, data on clinical characteristics and prognostic factors in such settings are scarce. We conducted a retrospective, observational cohort study to assess clinical characteristics and baseline predictors of mortality of COVID-19 patients hospitalized after an outbreak of SARS-CoV-2 infection in a LTCF. A total of 50 patients were included. Mean age was 80 years (SD, 12 years), and 24/50 (57.1%) patients were males. The overall in-hospital mortality rate was 32%. At Cox regression analysis, significant predictors of in-hospital mortality were: hypernatremia (HR 9.12), lymphocyte count < 1000 cells/µL (HR 7.45), cardiovascular diseases other than hypertension (HR 6.41), and higher levels of serum interleukin-6 (IL-6, pg/mL) (HR 1.005). Our study shows a high in-hospital mortality rate in a cohort of elderly patients with COVID-19 and hypernatremia, lymphopenia, CVD other than hypertension, and higher IL-6 serum levels were identified as independent predictors of in-hospital mortality. Given the small population size as major limitation of our study, further investigations are necessary to better understand and confirm our findings in elderly patients.
Diversity, structure and demography of coral assemblages on underwater lava flows of different ages at Reunion Island and implications for ecological succession hypotheses
Authors: Jouval Florian , Bigot Lionel , Bureau Sophie , Quod Jean-Pascal , Penin Lucie , Adjeroud Mehdi
Published: November 2020

Understanding colonization of new habitats and ecological successions is key to ecosystem conservation. However, studies on primary successions are scarce for reef-building corals, due to the rarity of newly formed substratum and the long-term monitoring efforts required for their long life cycle and slow growth rate. We analysed data describing the diversity, structure and demography of coral assemblages on lava flows of different ages and coral reefs at Reunion Island, to evaluate the strength and mechanisms of succession, and its agreement to the theoretical models. No significant differences were observed between the two habitats for most structure and demographic descriptors. In contrast, species richness and composition differentiated coral reefs from lava flows, but were not related to the age of the lava flow. We observed a strong dominance of Pocillopora colonies, which underline the opportunistic nature of this taxa, with life-history traits advantageous to dominance on primary and secondary successional stages. Although some results argue in favor of the tolerance model of succession, the sequences of primary successions as theorized in other ecosystems were difficult to observe, which is likely due to the high frequency and intensity of disturbances at Reunion, that likely distort or set back the expected successional sequences.
Trajectories of depressive symptoms and associated patterns of cognitive decline
Authors: Formánek Tomáš , Csajbók Zsófia , Wolfová Katrin , Kučera Matěj , Tom Sarah , Aarsland Dag , Cermakova Pavla
Published: November 2020

The aim was to investigate the pattern and rate of cognitive decline across distinctive trajectories of depressive symptoms in older adults. In this prospective multinational cohort study on 69,066 participants (on average 64 years at baseline, 55% women), assessments of cognitive functions (immediate recall, delayed recall, verbal fluency) and depressive symptoms (EURO-D scale) were conducted at 2-year intervals. The trajectories of depressive symptoms were obtained using latent growth mixture modelling, cognitive decline was assessed using smoothing splines and linear mixed effects models. Four distinct trajectories of depressive symptoms were identified: constantly low (n = 49,660), constantly high (n = 2999), increasing (n = 6828) and decreasing (n = 9579). Individuals with increasing and constantly high depressive symptoms showed linear cognitive decline, while those with constantly low and decreasing depressive symptoms had fluctuating cognition. Participants with increasing depressive symptoms had the fastest decline, while those with decreasing symptoms were spared from decline in cognition. This study suggests that the pattern as well as the rate of cognitive decline co-occurs with specific patterns of changes in depressive symptoms over time. The most pronounced cognitive decline is present in individuals, in whom depressive symptoms increase late in life. Unique mechanisms of cognitive decline may exist for subgroups of the population, and are associated with the trajectory of depressive symptoms.
Treating incarcerated inguinal hernias with TEP is a viable option for experienced surgeons
Authors: de Almeida Medeiros Kayo Augusto , Carvalho Bárbara Justo , Pipek Leonardo Zumerkorn , de Mesquita Gustavo Heluani Antunes , Nii Fernanda , Martines Diego Ramos , Iuamoto Leandro Ryuchi , Carneiro-D’Albuquerque Luiz Augusto , Meyer Alberto , Andraus Wellington
Published: November 2020

Despite inguinal hernias being a common problem in public health, there is still scarce information about the epidemiology of the complications, especially incarceration, and their influence on the laparoscopic surgical methods considering the role of the learning process of the surgeon. Compare laparoscopic totally extraperitoneal (TEP) approach in the repair of incarcerated and non-incarcerated inguinal hernias from the perspective of technical difficulty for trained surgeons. We obtained data about sex, age, location and type of hernia, surgery duration, ASA score, postoperative complications, previous surgeries and BMI. Groups were descriptively analyzed and statistically compared to verify how similar the samples were. 265 (90.1%) patients had non-incarcerated hernias and 29 (9.9%) incarcerated. We observed that there was no significant difference in the pattern of location (right, left or bilateral), sex, ASA, previous or complications between the two groups. Unilateral incarcerated hernias had longer operative times compared to non-incarcerated. No difference was found between bilateral hernias. We didn´t find significant epidemiological differences between incarcerated and non-incarcerated hernias. In our experience, with the limitation of a single-surgeon series, laparoscopic hernia repair achieved satisfactory results in terms of feasibility (especially for bilateral hernias) and safety.
Quantitative and functional characteristics of circulating and bone marrow PD-1- and TIM-3-positive T cells in treated multiple myeloma patients
Authors: Batorov Egor V. , Aristova Tatiana A. , Sergeevicheva Vera V. , Sizikova Svetlana A. , Ushakova Galina Y. , Pronkina Natalia V. , Shishkova Irina V. , Shevela Ekaterina Y. , Ostanin Alexander A. , Chernykh Elena R.
Published: November 2020

The aim of the present work was to evaluate counts and functional properties of PD-1+ and TIM-3+ T cells in peripheral blood (PB) and bone marrow (BM) of multiple myeloma (MM) patients following the induction therapy. Sixty patients were enrolled in the study, CD4+ and CD8+ T cells expressing PD-1 and TIM-3, intracellular production of IFNγ and intracellular expression of Granzyme B were assessed. Relative counts of the majority of circulating PD-1+, TIM-3+ and PD-1+TIM-3+ T cells were higher in MM patients with disease progression compared with individuals in remission. Frequencies of almost all evaluated PD-1+ and TIM-3+ T cell subsets were higher in BM samples compared with PB; circulating CD4+PD-1+, CD8+PD-1+, CD8+TIM-3+, CD8+PD-1+TIM-3+ T cells positively correlated with the same BM subsets. Circulating CD4+ T cells, expressing PD-1 and TIM-3 (including co-expressing subset), as well as CD8+PD-1+TIM-3+ T cells, and BM CD8+PD-1+ T cells correlated with serum B2-M levels. Sufficient frequencies of GrB+ and IFNγ+ subsets in PD-1-expressing T cells indicated their retained functional properties. TIM-3-expressing T cells and double positive PD-1+TIM-3+ populations showed diminished cytotoxic and cytokine-producing ability and therefore might be attributed to the exhausted compartment. To identify T cell exhaustion, it is necessary to evaluate T cells co-expressing PD-1, TIM-3 and other inhibitory signal molecules and to study their functional properties. Sustained functionality of PD-1-positive T cells may explain low efficacy and frequent immune-mediated adverse events during anti-PD-1 therapy in MM.
Cattle mitogenome variation reveals a post-glacial expansion of haplogroup P and an early incorporation into northeast Asian domestic herds
Authors: Mannen Hideyuki , Yonezawa Takahiro , Murata Kako , Noda Aoi , Kawaguchi Fuki , Sasazaki Shinji , Olivieri Anna , Achilli Alessandro , Torroni Antonio
Published: November 2020

Surveys of mitochondrial DNA (mtDNA) variation have shown that worldwide domestic cattle are characterized by just a few major haplogroups. Two, T and I, are common and characterize Bos taurus and Bos indicus, respectively, while the other three, P, Q and R, are rare and are found only in taurine breeds. Haplogroup P is typical of extinct European aurochs, while intriguingly modern P mtDNAs have only been found in northeast Asian cattle. These Asian P mtDNAs are extremely rare with the exception of the Japanese Shorthorn breed, where they reach a frequency of 45.9%. To shed light on the origin of this haplogroup in northeast Asian cattle, we completely sequenced 14 Japanese Shorthorn mitogenomes belonging to haplogroup P. Phylogenetic and Bayesian analyses revealed: (1) a post-glacial expansion of aurochs carrying haplogroup P from Europe to Asia; (2) that all Asian P mtDNAs belong to a single sub-haplogroup (P1a), so far never detected in either European or Asian aurochs remains, which was incorporated into domestic cattle of continental northeastern Asia possibly ~ 3700 years ago; and (3) that haplogroup P1a mtDNAs found in the Japanese Shorthorn breed probably reached Japan about 650 years ago from Mongolia/Russia, in agreement with historical evidence.
Serial clustering of extratropical cyclones: a review of where, when and why it occurs
Authors: Dacre Helen F. , Pinto Joaquim G.
Published: November 2020

Serial clustering of extratropical cyclones describes the passage of multiple cyclones over a fixed location within a given time period. Such periods often result in high precipitation totals and accumulated wind damage, leading to large societal and financial impacts. Here, we define the terminology to differentiate between several types of cyclone clustering and review multiple approaches used to quantify it. We provide an overview of current research activities including a review of serial cyclone clustering climatologies used to identify where clustering occurs. We review the dynamical mechanisms determining when and why serial cyclone clustering occurs for different timescales of interest. On daily timescales, serial cyclone clustering is often associated with a cyclone family and secondary cyclogenesis mechanisms. At longer timescales, active or inactive seasons are often associated with persistent large-scale flow patterns and their interaction with successive Rossby wave-breaking events. Finally, we discuss the knowledge gaps and current research opportunities.
Higher order interactions in complex networks of phase oscillators promote abrupt synchronization switching
Authors: Skardal Per Sebastian , Arenas Alex
Published: November 2020

Synchronization processes play critical roles in the functionality of a wide range of both natural and man-made systems. Recent work in physics and neuroscience highlights the importance of higher-order interactions between dynamical units, i.e., three- and four-way interactions in addition to pairwise interactions, and their role in shaping collective behavior. Here we show that higher-order interactions between coupled phase oscillators, encoded microscopically in a simplicial complex, give rise to added nonlinearity in the macroscopic system dynamics that induces abrupt synchronization transitions via hysteresis and bistability of synchronized and incoherent states. Moreover, these higher-order interactions can stabilize strongly synchronized states even when the pairwise coupling is repulsive. These findings reveal a self-organized phenomenon that may be responsible for the rapid switching to synchronization in many biological and other systems that exhibit synchronization without the need of particular correlation mechanisms between the oscillators and the topological structure.
Coupling conversion of methane with carbon monoxide via carbonylation over Zn/HZSM-5 catalysts
Authors: Wen Fuli , Zhang Jin , Chen Zhiyang , Zhou Ziqiao , Liu Hongchao , Zhu Wenliang , Liu Zhongmin
Published: November 2020

Coupling conversion of methane with carbon monoxide over Zn/HZSM-5 catalysts.
Insulin-regulated aminopeptidase deficiency impairs cardiovascular adaptations and placental development during pregnancy
Authors: Walton Sarah L. , Mirabito Colafella Katrina M. , Ansari Aneesa , Chai Siew Yeen , Denton Kate M.
Published: November 2020

Insulin-regulated aminopeptidase (IRAP), an enzyme that cleaves vasoactive peptides including oxytocin and vasopressin, is suggested to play a role in pregnancy and the onset of preeclampsia. Our aim was to examine the contribution of IRAP to arterial pressure regulation and placental development during pregnancy in mice. Mean arterial pressure and heart rate were measured via radiotelemetry in 12-week-old female wild-type and IRAP knockout mice. Females were time-mated with males of the same genotype. Placentae were collected at embryonic day 18.5 for histological analysis. Basal heart rate was ∼40 bpm lower in IRAP knockout females compared with wild-type females. The increase in heart rate across gestation was greater in IRAP knockout females than wild-type females. Neither basal nor gestational mean arterial pressure was different between wildtype and IRAP knockout females. Urine output and water intake of IRAP knockout mice were ∼45% less than wild-type mice at late gestation. IRAP deficiency had no effect on fetal weight. Morphological assessment of placentae revealed that IRAP deficiency was associated with reduced labyrinth surface area and accumulation of glycogen in the junctional zone. Our data demonstrate that IRAP deficiency alters maternal fluid handling and impairs placental labyrinth expansion at late gestation, indicating that IRAP contributes to the normal adaptions to pregnancy.
10.4 m GTC observations of the nearby VHE-detected GRB 190829A/SN 2019oyw
Authors: Hu Y.-D. , Castro-Tirado A. J. , Kumar A. , Gupta R. , Valeev A. F. , Pandey S. B. , Kann D. A. , Castellón A. , Agudo I. , Aryan A. , Caballero-García M. D. , Guziy S. , Martin-Carrillo A. , Oates S. R. , Pian E. , Sánchez-Ramírez R. , Sokolov V. V. , Zhang B.-B.
Published: November 2020

Aims.Gamma-ray burst (GRB) 190829A (z = 0.0785) was detected byFermiandSwiftand also at very high energy (VHE) by the High-Energy Stereoscopic System (H.E.S.S.) telescopes. The prompt emission displayed two emission episodes separated by a quiescent gap of ∼40 s. We present the 10.4 m Gran Telescopio Canarias (GTC) observations of the afterglow of GRB 190829A and its underlying supernova. We also compare GRB 190829A to GRB 180728A, a GRB with similar behaviour, and discuss the implications on underlying physical mechanisms producing these two GRBs.

Methods.We present multi-band photometric data along with spectroscopic follow-up observations taken with the 10.4 m GTC telescope. Together with the data from the prompt emission, the 10.4 m GTC data are used to understand the emission mechanisms and possible progenitor.

Results.A detailed analysis of the multi-band observations of the afterglow requires the cooling frequency to pass between the optical and X-ray bands at early epochs. The afterglow then transitions to the underlying supernova (SN) 2019oyw, which dominates later on.

Conclusions.Although the prompt emission temporal properties of GRB 190829A and GRB 180728A are similar, the two pulses are different in the spectral domain. We find that SN 2019oyw associated with GRB 190829A is powered by Ni decay and is a Type Ic-BL SN. The spectroscopic and photometric properties of this SN are consistent with those observed for SN 1998bw, but evolved earlier.
A comparative study of the ultrastructural characteristics of the mature spermatozoa of two fellodistomidsTergestia clonacanthaandT. laticollisand contribution to the phylogenetic knowledge of the Gymnophalloidea
Authors: Ndiaye Papa Ibnou , Marchand Bernard , Bâ Cheikh Tidiane , Justine Jean-Lou , Bray Rodney Alan , Quilichini Yann
Published: November 2020

The ultrastructure of the mature spermatozoa ofTergestia clonacanthaandT. laticolliscollected from the digestive tracts of fishes from New Caledonia is described using transmission electron microscopy and compared to that of related species. The spermatozoa of the two species exhibit the general pattern described in most digeneans, namely two axonemes with the 9 + “1” pattern of the Trepaxonemata, nucleus, mitochondrion, cortical microtubules, an external ornamentation of the plasma membrane, spine-like bodies and granules of glycogen. The spermatozoa ofT. clonacanthaandT. laticollisshow the same ultrastructural model with some specificities in each case, particularly in the disposition of the structures in the posterior extremities of the spermatozoon. This study confirms that ultrastructural characters of the mature spermatozoon are useful tools for the phylogenetic analysis of the Digenea.
Anämie und Eisenmangel – Behandlungsoptionen bei chronischer Nierenerkrankung und chronischer Herzinsuffizienz
Authors: Emrich Insa E. , Böhm Michael , Heine Gunnar H.
Published: November 2020

Was ist neu?

Therapie mit Eisenpräparaten Mit PIVOTAL erschien 2018 die erste kardiovaskuläre Endpunktstudie zur Eisensubstitution bei Dialysepatienten, die eine prognostische Überlegenheit einer Hochdosiseisentherapie gegenüber einer restriktiveren Eisenapplikation aufzeigte. Mit AFFIRM-AHF, IRONMAN, FAIR-HF2 und HEART-FID überprüfen aktuell gleich 4 Studien die Bedeutung einer intravenösen Eisenapplikation auf kardiovaskuläre Endpunkte bei Patienten mit Herzinsuffizienz.

Ausblick HIF-Stabilisatoren erlauben eine orale Anämie-Behandlung bei chronischer Nierenerkrankung. Erste klinische Studien zeigten eine „Nichtunterlegenheit“ von HIF-Stabilisatoren gegenüber der Behandlung mittels rekombinanten Erythropoetins (EPO)/Erythropoese-stimulierenden Agenzien (ESA) in Bezug auf den Hämoglobinanstieg. Finale Ergebnisse großer Studien mit kardiovaskulären Endpunkten sind aktuell noch ausstehend. In diesen Studien muss das Sicherheitsprofil von HIF-Stabilisatoren überprüft werden, da HIF-Stabilisatoren die Transkription zahlreicher Gene auch jenseits der Hämatopoese verändern. In der klinischen Kardiologie spielen HIF-Stabilisatoren aktuell (noch) keine Rolle. Unter der Therapie mittels SGLT-II-Inhibitoren konnte ein Anstieg des Hämatokrits beobachtet werden, welcher sich nicht allein durch diuretische Effekte erklären lässt. Die genaue pharmakodynamische Wirkweise ist noch offen.
57-jährige Patientin mit Blasen und striatiformen Erythemen an den Extremitäten
Authors: Münchhoff-Barker Christina , Tittelbach Jörg , Elsner Peter
Published: November 2020

Anamnese Bei einer 57-jährigen Patientin traten nach wiederholter Gartenarbeit schmerzhafte Hautveränderungen auf. Bei der Vorstellung in der zentralen Notaufnahme zeigten sich Bullae, Striae und Erytheme an den lichtexponierten Arealen.

Untersuchungen und Diagnose Laborchemisch zeigten sich leicht erhöhte Entzündungswerte. Die körperliche Untersuchung zeigte keine weiteren Besonderheiten. Es erfolgte die Übernahme durch die Dermatologie des Universitätsklinikums Jena. Aufgrund der Anamnese und des klinischen Befundes wurde die Diagnose Dermatitis bullosa pratensis (Wiesengrasdermatitis) gestellt.

Therapie und Verlauf Es erfolgte neben lokaler Therapie mit Glukokortikosteroiden und sterilem Punktieren der Blasen eine intravenöse Therapie mit Prednisolon.

Folgerung Dermatitis bullosa pratensis gehört zu den photophytotoxischen Dermatitiden und wird durch die Kombination von Photosensibilisatoren und ultraviolettem Licht ausgelöst. Es ist von Bedeutung, sich bei Kontakt mit Pflanzen, die Photosensibilisatoren enthalten, vor UV-Licht ausreichend zu schützen. Das Krankheitsbild ist leicht zu vermeiden, umso wichtiger ist es, das Risiko zu kennen und die notwendigen Schutzmaßnahmen einzuhalten.
Enhanced critical temperatures in the strongly overdoped iron-based superconductors AFe2As2 (A = K, Cs, Rb) observed by point contacts
Authors: Naidyuk Yu. G. , Kvitnitskaya O. E. , Efremov D. V. , Drechsler S.-L.
Published: November 2020

A remarkable several times increase (up to 10 K) of the superconducting critical temperature Tc has been observed in point contacts created on the base of single crystals AFe2As2 (A = K, Cs, Rb). Possible reasons for such a Tc increase in point contacts are briefly discussed on a qualitative level. Among them, it is most likely attributed to interfacial carrier doping and/or uniaxial non-homogeneous pressure arising when the contact is created.
Mayer group expansion for solids: Application to polymorphic transition in highly compressed nitrogen
Authors: Yakub E. S. , Yakub L. N.
Published: November 2020

The Mayer group expansion for solids proposed earlier is applied in prediction of the location of polymorphic phase transition line between the cubic and layered phases of polymeric nitrogen. The comparison with existing measurements revealed that theoretical calculations based on the proposed potential model calibrated on ab initio energy calculations are in agreement with existing experimental data. Predicted location of the polymorphic transition line and specific behavior of thermal properties of both phases in a wide temperature range is discussed.
Model-free adaptive control for the PEMFC air supply system based on interval type-2 fuzzy logic systems
Authors: Luo Gang , Ma Bingxin , Wang Zezheng , Yin Ling , Wang Yongfu
Published: November 2020

Control aims to avoid oxygen starvation and maximize the net power output by maintaining the optimal oxygen excess ratio (OER), which varies between 1.8 and 2.5. Because of the nonlinearity of the proton exchange membrane fuel cell (PEMFC) air supply system and the different conditions, ensuring an optimal OER is still a challenge. In this study, a model-free adaptive controller is presented for the PEMFC air supply system based on feedback linearization and interval type-2 fuzzy logic systems (IT2 FLSs). Theoretical analysis and experimental results verify the effectiveness of the proposed control scheme. For the theoretical analysis, first, the PEMFC air supply system is transformed into a canonical form with the feedback linearization technique. Then, zero-dynamics stability is discussed in detail to determine the stability of the internal dynamics. Finally, an adaptive interval type-2 fuzzy logic system controller (AIT2FLSC) is designed on the basis of the Lyapunov stability theory, which does not require complete a priori knowledge of the system dynamics. For the experimental results, the root mean square error (RMSE), variance, and standard deviation (SD) of the tracking error are used as tracking performance metrics to evaluate the control accuracy of the proposed AIT2FLSC, which are 0.0968, 0.0093, and 0.0962, respectively. Compared with the traditional proportion integration differentiation controller (RMSE 0.1119, variance 0.0122, and SD 0.1105), this proposed algorithm obtains better adaptability and the RMSE of the tracking error improves 13.48%. Compared with the adaptive type-1 fuzzy logic system controller (AT1FLSC) (RMSE 0.1076, variance 0.0113, and SD 0.1063), this AT2FLSC has a stronger ability to deal with uncertainty and the RMSE of the tracking error improves 10% when the stack temperature is fixed (353.15 K). Furthermore, when the stack temperature is time-varying, the RMSE, variance, and SD of the tracking error under the AIT2FLSC are 0.0966, 0.0092, and 0.0960, respectively, which is less than AT1FLSC (0.1085, 0.0115, and 0.1073) and the RMSE of the tracking error improves 10.99%.
Solvent independent symmetry-breaking charge separation in terrylenediimide guanine-quadruplex nanoparticles
Authors: Powers-Riggs Natalia E. , Zuo Xiaobing , Young Ryan M. , Wasielewski Michael R.
Published: November 2020

G-quadruplex assemblies are a promising tool for self-assembling π-stacked chromophore arrays to better understand their photophysics. We have shown that coupling a single guanine moiety to terrylenediimide (TDI) produces a structure (GTDI) that self-assembles in tetrahydrofuran (THF) into a nearly monodisperse guanine-quadruplex structure having 16 π-stacked layers (GTDI4)16. The TDI surfaces were determined to have a high degree of cofacial overlap and underwent quantitative symmetry-breaking charge separation (SB-CS) upon photoexcitation. Here, we more deeply examine the relationship between solvent and aggregate formation and develop insights into structure–function relationships over a variety of solvent polarities and hydrogen-bonding capabilities. At high concentrations, GTDI assembles into guanine-quadruplex structures (GTDI4)16 in THF and toluene, as well as (GTDI4)9 in pyridine and benzonitrile. Transient absorption spectroscopy shows that SB-CS occurs in all solvents, regardless of their static dielectric constants, but the SB-CS yield is determined by structure. Solvent polarity independent SB-CS generation is also observed in GTDI films, where there is a complete absence of solvent.
Vapor–liquid equilibria and cohesive r−4 interactions
Authors: Sadus Richard J.
Published: November 2020

The role of cohesive r−4 interactions on the existence of a vapor phase and the formation of vapor–liquid equilibria is investigated by performing molecular simulations for the n-4 potential. The cohesive r−4 interactions delay the emergence of a vapor phase until very high temperatures. The critical temperature is up to 5 times higher than normal fluids, as represented by the Lennard-Jones potential. The greatest overall influence on vapor–liquid equilibria is observed for the 5–4 potential, which is the lowest repulsive limit of the potential. Increasing n initially mitigates the influence of r−4 interactions, but the moderating influence declines for n > 12. A relationship is reported between the critical temperature and the Boyle temperature, which allows the critical temperature to be determined for a given n value. The n-4 potential could provide valuable insight into the behavior of non-conventional materials with both very low vapor pressures at elevated temperatures and highly dipolar interactions.
Electrical properties of (11-22) Si:AlGaN layers at high Al contents grown by metal-organic vapor phase epitaxy
Authors: Foronda Humberto M. , Hunter Daniel A. , Pietsch Mike , Sulmoni Luca , Muhin Anton , Graupeter Sarina , Susilo Norman , Schilling Marcel , Enslin Johannes , Irmscher Klaus , Martin Robert W. , Wernicke Tim , Kneissl Michael
Published: November 2020

In this work, the growth and conductivity of semipolar AlxGa1−xN:Si with (11-22) orientation are investigated. AlxGa1−xN:Si (x = 0.60 ± 0.03 and x = 0.80 ± 0.02) layers were grown with different SiH4 partial pressures, and the electrical properties were determined using Hall measurements at room temperature. The aluminum mole fraction was measured by wavelength dispersive x-ray spectroscopy and x-ray diffraction, and the Si-concentration was measured by wavelength dispersive x-ray spectroscopy and secondary ion mass spectroscopy. Layer resistivities as low as 0.024 Ω cm for x = 0.6 and 0.042 Ω cm for x = 0.8 were achieved. For both aluminum mole fractions, the resistivity exhibits a minimum with the increasing Si concentration, which can be explained by compensation due to the formation of cation vacancy complexes at high doping levels. The onset of self-compensation occurs at larger estimated Si concentrations for larger Al contents.
Detecting alcohol vapors using two-dimensional copper-based Ruddlesden–Popper perovskites
Authors: Groeneveld Bart G. H. M. , Loi Maria Antonietta
Published: November 2020

The detection of alcohol vapors has many important applications, such as measuring the breath ethanol content to prevent drug-impaired driving. A medical application is the detection of 1-propanol because this compound was found to be a potential marker for lung cancer screening. This work reports an alcohol sensor using the two-dimensional Ruddlesden–Popper perovskite bis(phenethylammonium) tetrachlorocuprate—(PEA)2CuCl4, also known as phenethylammonium copper chloride—as the sensing material. The device is based on a change in conductance upon exposure to alcohol vapors. A comparison between pristine (PEA)2CuCl4 and (PEA)2CuCl4 after a treatment with ultraviolet light shows that the latter has a higher conductance. Devices made with this UV-converted material show a strong response to 1-propanol vapors, starting from a concentration around 2000 parts per million (ppm). Additionally, these devices demonstrate stable behavior in a nitrogen atmosphere. During the stabilization of the 1-propanol flow rate, the concentration fluctuates. These fluctuations were detected by monitoring the current of the device over time, down to steps in 100 ppm around a concentration of 8000 ppm. The conductance of the devices decreases in contact with air. However, this process can be reversed by additional ultraviolet illumination, thereby making the devices reusable.
Effects of long-term exposure to music on behaviour, immunity and performance of piglets
Authors: Zhao Peng , Zhao Jianing , Liu Honggui , Zhang Runxiang , Li Jianhong , Zhang Mingyue , Wang Chao , Bi Yanju , Zhang Xin , Yi Ran , Li Xiang , Bao Jun
Published: November 2020

Context Music induces physiological responses in animals, and as an enriched environment, it may have a positive effect on behaviour and productivity. Aims This study aimed to determine the effects of different kinds of music on immunity, stress response and performance of piglets. Methods In total, 144 hybrid piglets (Yorkshire × Durac × Minpig) at the age of 7 weeks were divided into three treatment groups: slow-tempo string music (65 beats per min), fast-tempo wind music (200 beats per min), and control (i.e. no music). Exposure to music lasted for 42 days, from 8 to 14 weeks of age. During the experimental period, behavioural activities were observed, and physiological parameters, immune responses and growth performance were measured. Key results Results showed that long-term music exposure increased (P < 0.01) playing and tail-wagging behaviours compared with the control group, but had no effect (P > 0.05) on walking, lying, exploring, fighting or feeding behaviours. No effect (P > 0.05) was found on the levels of growth hormone, salivary cortisol, serum cortisol, adrenocorticotrophic hormone, β-endorphin or dopamine, or on the performance of growing pigs. However, the specific music type slow-tempo string significantly (P < 0.05) increased interleukin-4. Conclusions Long-term exposure to music does not affect stress response or growth performance in piglets. However, it promotes positive mood as indicated by increased playing and tail-wagging activities, and induces positive immunomodulation through increased interleukin-4 levels in piglets. Implications Exposure to music may be used to promote positive mood, and hence enhance welfare, in piglets.
Australian rangelands science – a strategic national asset
Authors: Campbell Andrew
Published: November 2020

Producing, processing and distributing food is the biggest thing that humans do on the planet. In aggregate terms, agriculture has been very successful in ensuring that global food production has more than kept pace with global population growth over recent decades. However, in recent years concerns have intensified about the quality, equity, sustainability and resilience of the food system. Only around one-third of all people on Earth are eating a healthy diet. The food system is the biggest user and polluter of land and water, the biggest driver of habitat and biodiversity loss, and on track to be the biggest emitter of greenhouse gases. The recent emergence of a novel coronavirus and the resultant COVID-19 pandemic has further highlighted the systemic risks to human health from current food production and distribution systems. How to produce more, healthier and safer food, much more efficiently and sustainably, in more difficult climates, and how to share it more equitably, is an existential challenge for humanity. Australian science, and rangeland science in particular, is well-placed to play a leadership role across the Indo-Pacific in this endeavour. The Australian innovation system in agriculture and natural resource management has long had to contend with highly variable climates and extreme weather events, to produce competitive products for global markets with minimal subsidies. The know-how, and associated policies and institutions developed in doing so, are a strategic national asset and an important element of Australian soft power in our region.
On the relationship between middles and passives
Authors: Ahn Mikyung , Yap Foong Ha
Published: November 2020

Previous studies using diachronic data from theSejongHistorical Corpus have traced the semantic extension of voice marker -ecifrom middle to passive uses (e.g.Ahn & Yap 2017). In this study, based on data from theSejongContemporary Spoken Corpus, we further examine the relationship between middle and passive uses of -eciconstructions, with special attention to the neutralization of adversative readings that give rise to generalized (in addition to adversative) middle and passive -eciconstructions. Our analysis reveals that judgments about adversative readings in Contemporary Korean are not emergent solely from the semantics of the verb or adjective preceding -ecibut additionally are emergent and grounded in the interaction between discourse participants. The distributional characteristics of -ecialso show a strong interaction between voice and tense-aspect-mood (TAM). There is also some interaction effects from register and text type/genre, particularly in the usage frequency distribution of spontaneous and passive -eciconstructions. In addition, contrary to the traditional notion that -eciis essentially a passive marker, in real usage, -eciis still far more frequently used as a middle marker than a passive marker.
Oil and its discontents: the political economy of artisanal refining in Nigeria
Authors: Nwozor Agaptus , Olanrewaju John , Ake Modupe , Okidu Onjefu
Published: November 2020

This briefing examines the forces behind and some of the consequences of artisanal oil refining in Nigeria. Critical political economy is used to explore the asymmetrical power relations between the people, government and oil companies, drawing on new material to account for an unexplored dimension of the marginalisation of oil-bearing communities.
Investigation of argumental oscillations of a physical pendulum
Authors: Pedersen Henrik B , Madsen Magnus Linnet , Andersen John E V , Nielsen Torsten G
Published: November 2020

We report an experimental investigation as well as an intuitive theoretical description of argumental oscillations of a physical pendulum, i.e. a driven pendulum where the driving torque depends explicitly on the angle (argument) of the pendulum. With an idealized analysis, we derive three conditions for the occurrence of sustained argumental oscillations: the first establishes the phase matching of the driving system and the pendulum, the second defines the balance of energy gain and loss, and the third identifies the nature of stabilization of the oscillations. For the experimental investigation, we use a recently established pendulum setup, with a further developed suspension mechanism that essentially eliminates friction from the pivot. The pendulum is equipped with a permanent magnet oriented along the pendulum body and a current carrying solenoid located vertically below the pendulum to facilitate an angular dependent excitation. Through studies of free oscillations, we identify the passive electromagnetic pendulum–solenoid interaction as central for the resulting dynamics of the driven pendulum, e.g. it provides a major mechanism of energy dissipation and it modifies the actual dependency of the pendulum frequency on the maximum angle. For one realization of argumental oscillations (Doubochinski’s pendulum), we report experimental frequency response curves, i.e. the oscillation amplitude and the phase relative to the external torque as a function of the driving frequency for selected harmonics (n = 5–13) of the pendulum frequency. The results show the characteristic signatures of argumental oscillations derived from the idealized model, but also display clear deviations corresponding to the complex nature of the interaction of the pendulum and the solenoid.
Some insight into Feynman’s approach to electromagnetism
Authors: Mauro Marco Di , De Luca Roberto , Esposito Salvatore , Naddeo Adele
Published: November 2020

We retrace an ab initio relativistic derivation of the inhomogeneous Maxwell’s equations that was developed by Feynman in unpublished notes, clarifying the analogies and the differences with analogous treatments present in the literature. Unlike the latter, Feynman’s approach stands out because it considers electromagnetic potentials as primary, reflecting his ideas about the quantum foundations of electromagnetism.
An infinitely differentiable model for deploying parachutes
Authors: Rodrigues H , Soares A L , dos Santos A C , de Pinho M O
Published: November 2020

In this article, we identify a general structure for the drag force that acts on a model rocket equipped with a parachute. This structure makes use of functions that promote a continuous transition between different magnitudes of the drag force. The kinematics of this system is discussed for some concrete transition functions with the intention to arrive at a continuously differentiable model.
Recovering a quasilinear conductivity from boundary measurements
Authors: Shankar Ravi
Published: November 2020

We consider the Calderón type inverse problem of recovering an isotropic quasilinear conductivity from the Dirichlet-to-Neumann map when the conductivity depends on the solution and its gradient. We show that the conductivity can be recovered on an open subset of small gradients, hence extending a partial result of Muñoz and Uhlmann to all real analytic conductivities. We also recover non-analytic conductivities with additional growth assumptions along large gradients. Moreover, the results hold for non-homogeneous conductivities if the non-homogeneous part is assumed known.
Hot-wire probe design and calibration for high-speed, high-temperature flows
Authors: Mirhashemi Arman , Szczudlak Joshua D , Morris Scott C
Published: November 2020

The use of hot-wire anemometry in high-speed, high-temperature flows with large temperature variations presents additional challenges compared with measurements in an incompressible flow at a nearly constant temperature. This work focuses on the use of hot-wires under conditions with a flow velocity of up to

455

m
s

−
1

, temperatures up to

650

K

, and mean temperature variations of approximately

100

K

. This research was motivated by experiments simulating some of the conditions of the high-pressure turbine inlet region of a gas-turbine engine. Two separate factors in this work facilitated hot-wire measurements under the above conditions. The first was the design of a custom hot-wire probe and sensor attachment procedure. The design used high-temperature materials capable of meeting the structural requirements of high-speed flow. The second objective was the development of a new temperature compensation method to provide low bias errors over a large range of gas temperatures and Mach numbers. The results demonstrate that both probe and sensor were able to operate at high Mach number and high-temperatures for several days without issue. Mean velocity results are compared with pneumatic probe measurements, and are found to be within the expected range of uncertainty.
Anomalous nucleation of crystals within amorphous germanium nanowires during thermal annealing
Authors: Camara O , Mir A H , Greaves G , Donnelly S E , Hinks J A
Published: November 2020

In this work, germanium nanowires rendered fully amorphous via xenon ion irradiation have been annealed within a transmission electron microscope to induce crystallization. During annealing crystallites appeared in some nanowires whilst others remained fully amorphous. Remarkably, even when nucleation occurred, large sections of the nanowires remained amorphous even though the few crystallites embedded in the amorphous phase were formed at a minimum of 200 °C above the temperature for epitaxial growth and 100 °C above the temperature for random nucleation and growth in bulk germanium. Furthermore, the presence of crystallites was observed to depend on the diameter of the nanowire. Indeed, the formation of crystallites occurred at a higher annealing temperature in thin nanowires compared with thicker ones. Additionally, nanowires with a diameter above 55 nm were made entirely crystalline when the annealing was performed at the temperature normally required for crystallization in germanium (i.e. 500 °C). It is proposed that oxygen atoms hinder both the formation and the growth of crystallites. Furthermore, as crystallites must reach a minimum size to survive and grow within the amorphous nanowires, the instability of crystallites may also play a limited role for the thinnest nanowires.
Characterization of ZnO/AlO
x
/benzene thin-film heterostructures grown through atomic layer deposition/molecular layer deposition
Authors: Krahl Fabian , Ge Yanling , Karppinen Maarit
Published: November 2020

Multilayer thin-film structures are promising for many future high-tech applications. We investigate the structure of polycrystalline ZnO thin films with sub-nanometer amorphous inorganic (AlO
x
) and organic (benzene) layers grown by atomic/molecular layer deposition. Small quantities of aluminium are typically introduced in ZnO films for doping, while one of the intended functions of the organic layers is to block thermal conductivity. We apply the AlO
x
and benzene layers both simultaneously and separately, and investigate the resultant superlattice films with transmission electron microscopy, x-ray reflectivity and x-ray diffraction measurements. The study reveals that both AlO
x
and benzene form distinct layers in the ZnO matrix even down to one atomic/molecular layer. Furthermore, we demonstrate that despite the clear layering, the ZnO grains can penetrate through thin (below ca. 2 nm) benzene and AlO
x
layers.