bluuebunny/crossref_metadata_2025 huggingface dataset:
Graphene/MoS2/Graphene Vertical Heterostructure‐Based Broadband Photodetector with High Performance
Authors: Gao Shan , Wang Ziqian , Wang Huide , Meng Fanxu , Wang Pengfei , Chen Si , Zeng Yonghong , Zhao Jinlai , Hu Haiguo , Cao Rui , Xu Zhongquan , Guo Zhinan , Zhang Han
Published: December 2020

Molybdenum disulfide (MoS2) is considered as a promising 2D material for optoelectronic applications due to its excellent electrical and optical properties. A semimetal material with zero bandgap, like graphene, can extend response range of MoS2‐based photodetectors to wider spectral region. Here, a graphene/MoS2/graphene vertical heterostructure is demonstrated, where Schottky barriers are formed between MoS2 and graphenes. The introduction of graphene can effectively widen the working wavelength of the device from visible to IR range. Simultaneously, the shortened transmit distance for the photogenerated carriers between the source and drain electrodes in the vertical heterostructure leads to faster response speed compared with MoS2‐based photodetectors. Besides, the graphene/MoS2/graphene photodetector shows excellent performance with an enhanced responsivity of 414 A W−1 at 532 nm and 376 A W−1 at 2000 nm, and a broad working wavelength ranging from 405 to 2000 nm. These excellent performances prove that the design of graphene based vertical heterostructure can provide new ideas for the development of high‐performance photodetectors in future.
Responsive Photonic Liquid Crystalline Flakes Produced by Ultrasonication
Authors: Sol Jeroen A. H. P. , Kessels Lana M. , del Pozo Marc , Debije Michael G.
Published: December 2020

Responsive materials that alter their color in response to environmental changes can be used as optical sensors. Chiral nematic liquid crystals are photonic materials that selectively reflect specific wavelengths of light and have been made environmentally responsive. Herein, the use of ultrasonication of responsive cholesteric liquid‐crystal network films to form structurally colored flakes that demonstrate color changes when moved from an aqueous to dry environment and back again is demonstrated, which suggests a scalable technique to form quantities of responsive particles that could conceivably be embedded in permeable hosts to allow the optical detection of humidity or certain chemical species.
From Cyclopentasilane to Thin‐Film Transistors
Authors: Gerwig Maik , Ali Abid Shaukat , Neubert David , Polster Sebastian , Böhme Uwe , Franze Georg , Rosenkranz Marco , Popov Alexey , Ponomarev Ilia , Jank Michael P. M. , Viehweger Christine , Brendler Erica , Frey Lothar , Kroll Peter , Kroke Edwin
Published: December 2020

Cyclopentasilane (CPS) has been studied as an liquid precursor for the deposition of thin silicon films for printed electronics and related applications. The processing involves a UV‐induced prepolymerization of CPS followed by liquid deposition and low‐temperature thermolysis. An insight into the oligomer and polymer formation including crosslinking in solution using 29Si NMR spectroscopy and electron spin resonance spectroscopy is reported. Formation of SiH (T‐units) and SiH3 (M‐units) is observed as well as short‐lived paramagnetic species. Additionally, the polymerization is followed by Raman spectroscopy. Reactive molecular dynamics simulations are applied to develop a theoretical model for the CPS‐ring‐opening and crosslinking steps. The experimental and computational data correspond well to each other and allow insight into the mechanism of polymer formation. The processing steps include spin‐coating, thermal drying, and conversion to amorphous silicon, H‐passivation, and fabrication of a CPS‐derived thin‐film transistor (TFT), without intermediate silicon crystallization. Further improvement is gained by using tetralene as a solvent, leading to a reduction of the time‐consuming polymerization step by one order of magnitude compared to cyclooctane. The overall quality and characteristics of the CPS‐derived spin‐coated silicon thin films correspond to standard plasma enhanced chemical vapor deposition‐derived devices with respect to performance levels.
Fertilizer nitrogen recovery of irrigated spring malt barley
Authors: Rogers Christopher W. , Loomis Grant
Published: December 2020

Well‐defined nitrogen (N) management in irrigated two‐row malting barley (Hordeum vulgare L.) is critical for yield and quality and to minimize environmental impacts. Data on fertilizer N recovery efficiency (FNRE) and the fate of fertilizer‐N in the soil are lacking. The study objective was to determine uptake and partitioning of 15N‐labeled urea in the plant and soil. Urea was either surface applied or incorporated at a total N rate (inorganic‐N + applied N) of 214 kg N ha–1 at planting. Three malt cultivars were grown, and samples were collected four times during the growing season (Feekes growth stages 4/5, 10.0, 11.2, and 11.4). Barley plants at Feekes 11.2 and 11.4 were separated into vegetative tissue and spikes. Plant N accumulation was lowest at Feekes 4/5 and reached a maximum at Feekes 11.2, whereas FNRE was greatest at Feekes 10.0. Nitrogen was redistributed from vegetative tissue to the spike from Feekes 11.2 to 11.4. Plant FNRE averaged 43% at Feekes 11.4. Total plant–soil FNRE for the surface application was 66%, which was less than the incorporated FNRE of 77%. Results provide evidence of the increased plant–soil system FNRE of incorporated applications in high‐input barley production systems compared with surface applications despite no yield difference. Similar FNRE as compared to previous work with lower yields was measured, and modern cultivars out‐yielded an older cultivar with no reduction in FNRE. Results of the study indicate that a relatively high plant–soil system FNRE of irrigated malting barley was achieved under high‐input, irrigated conditions common in southern Idaho.
Structured silicalite‐1 encapsulated Ni catalyst supported on SiC foam for dry reforming of methane
Authors: Chen Huanhao , Shao Yan , Mu Yibing , Xiang Huan , Zhang Rongxin , Chang Yabin , Hardacre Christopher , Wattanakit Chularat , Jiao Yilai , Fan Xiaolei
Published: December 2020

Structured silicalite‐1 zeolite encapsulated Ni catalyst supported on silicon carbide foam (i.e., Ni@S1‐SiC) was prepared using a new yet simple one‐pot method, showing the significantly improved anti‐sintering and anti‐coking performance in comparison with the conventional supported and encapsulated Ni catalysts (i.e., Ni/S1, Ni/S1‐SiC, and Ni@S1), in catalytic dry reforming of methane (DRM). The developed Ni0.08@S1‐SiC catalyst showed high CO2/CH4 conversions of >85% and H2/CO molar ratio of >0.85 at 700°C, outperforming other control catalysts under investigation. Additionally, the Ni0.08@S1‐SiC catalyst demonstrated high turnover frequency (TOF) values of ~5.6 and ~2.1/s regarding to CO2/CH4 conversions at 400°C, exhibiting excellent stability and low pressure‐drop during 100 hr on stream evaluation. Post‐reaction characterization of the used catalysts demonstrated that the combination of zeolite encapsulated Ni catalysts and SiC foam enabled well‐dispersed and ultrafine Ni nanoparticles, low pressure drop and intensified transfer steps, presented excellent anti‐sintering and anti‐coking abilities.
Prevalence and risk factors of radial ray deficiencies: A population‐based case–control study
Authors: Syvänen Johanna , Raitio Arimatias , Helenius Ilkka , Löyttyniemi Eliisa , Lahesmaa‐Korpinen Anna‐Maria , Gissler Mika , Nietosvaara Yrjänä
Published: December 2020

Radial ray deficiency is the most common congenital deficiency of the upper limb. The aim of our study was to investigate maternal risk factors for radial ray deficiencies. We conducted a nationwide population‐based case–control study using national registers. All cases with a radial ray deficiency born between 1996 and 2008 were included in the study and compared with five controls without limb deficiency. In total, 115 (10 isolated, 18 with multiple congenital anomalies, and 87 syndromic) cases with radial ray deficiencies were identified and compared with 575 matched controls. The total prevalence in Finland was 1.22 per 10,000 births. No significant risk factors were observed for nonsyndromic cases. In the syndromic group, advanced maternal age (≥35 years) increased the risk of radial aplasia (aOR 2.45, 95% CI 1.37–4.36), and a similar association was observed with multiple pregnancy (aOR 2.97, 1.16–7.62) and male sex (aOR 1.96, 1.18–3.25). Valproic acid was also a risk factor (p = .002). In conclusion, novel associations in the syndromic group of advanced maternal age and multiple pregnancy and increased risk of radial ray deficiencies were observed. Also, early reports on increased risk of RRD associated with valproate and male sex were supported by our results.
Anionic Bisoxazoline Ligands Enable Copper‐Catalyzed Asymmetric Radical Azidation of Acrylamides
Authors: Wu Lianqian , Zhang Zhihan , Wu Dunqi , Wang Fei , Chen Pinhong , Lin Zhenyang , Liu Guosheng
Published: December 2020

Asymmetric radical azidation for the synthesis of chiral alkylazides remains a tremendous challenge in organic synthesis. We report here an unprecedented highly enantioselective radical azidation of acrylamides catalyzed by 1 mol % of a copper catalyst. The substrates were converted to the corresponding alkylazides in high yield with good‐to‐excellent enantioselectivity. Notably, employing an anionic cyano‐bisoxazoline (CN‐Box) ligand is crucial to generate a monomeric CuII azide species, rather than a dimeric CuII azide intermediate, for this highly enantioselective radical azidation.
Binding‐Mediated Formation of Ribonucleoprotein Corona for Efficient Delivery and Control of CRISPR/Cas9
Authors: Wu Jinjun , Peng Hanyong , Lu Xiufen , Lai Maode , Zhang Hongquan , Le X. Chris
Published: December 2020

Protein coronae formed with nanoparticles confer several useful properties. However, the non‐specific nature of protein corona formation makes it difficult to deliver specific proteins for therapeutic applications. Herein, we report on the construction of a new type of protein corona, termed binding‐mediated protein corona. This new corona enables the efficient and controllable delivery of functional proteins, which is otherwise challenging for conventional protein coronae. We show the design and delivery of the ribonucleoprotein corona for the CRISPR/Cas9 system. Successful gene editing in human cell lines (Hela and HEK293) demonstrates the efficient delivery, high stability, low cytotoxicity, and well‐controlled activity of the Cas9‐guide RNA ribonucleoprotein. The binding‐mediated protein corona strategy opens up new opportunities for therapeutic protein delivery.
The Molecular Tête‐à‐Tête between G‐Quadruplexes and the i‐motif in the Human Genome
Authors: Sengupta Pallabi , Bose Debopriya , Chatterjee Subhrangsu
Published: December 2020

G‐Quadruplex (GQ) and i‐motif structures are the paradigmatic examples of nonclassical tetrastranded nucleic acids having multifarious biological functions and widespread applications in therapeutics and material science. Recently, tetraplexes emerged as promising anticancer targets due to their structural robustness, gene‐regulatory roles, and predominant distribution at specific loci of oncogenes. However, it is arguable whether the i‐motif evolves in the complementary single‐stranded region after GQ formation in its opposite strand and vice versa. In this review, we address the prerequisites and significance of the simultaneous and/or mutually exclusive formation of GQ and i‐motif structures at complementary and sequential positions in duplexes in the cellular milieu. We discussed how their dynamic interplay Sets up cellular homeostasis and exacerbates carcinogenesis. The review gives insights into the spatiotemporal formation of GQ and i‐motifs that could be harnessed to design different types of reporter systems and diagnostic platforms for potential bioanalytical and therapeutic intervention.
Flow‐driven Surface Instabilities of Tubular Chitosan Hydrogel
Authors: Kumar Pawan , Hajdu Cintia , Tóth Ágota , Horváth Dezső
Published: December 2020

Spatial structures break their symmetry under the influence of shear stress arising from fluid flow. Here, we present surface instabilities appearing on chitosan tubes when an acidic solution of chitosan with various molecular weight is injected into a pool of sodium hydroxide solution. At slow flow rates wrinkle‐to‐fold transition takes place along the direction of the flow yielding a banded structure. For greater injection rates we observe coexisting modes of wrinkles and folds which are stabilized to periodic wrinkles when the alkaline concentration is increased. The instabilities are characterized by the scaling laws of the pattern wavelength and amplitude with the tube characteristics. Our experimental adaptation of mechanical instabilities provides a new in situ method to create soft biomaterials with the desired surface morphology without the use of any prefabricated templates.
Rotavirus infection causes mesenteric lymph node hypertrophy independently of type I interferon or TNF‐α in mice
Authors: Nakawesi Joy , Konjit Getachew Muleta , Dasoveanu Dragos‐Christian , Johansson‐Lindbom Bengt , Lahl Katharina
Published: December 2020

Lymphoid organ hypertrophy is a characteristic feature of acute infection and is considered to enable efficient induction of adaptive immune responses. Accordingly, oral infection with rotavirus induced a robust increase in cellularity in the mesenteric LNs, whose kinetics correlated with viral load and was caused by halted lymphocyte egress and increased recruitment of cells without altered cellular proliferation. Lymphocyte sequestration and mesenteric LN hypertrophy were independent of type 1 IFN receptor signaling or the continuous presence of TNF‐α. Our results support previous findings that adaptive immunity toward rotavirus is initiated primarily in the mesenteric LNs and show that type I IFN or TNF‐α are not required to coordinate the events involved in the LN response.
Hospital responses to the refinement of reimbursements by treatment intensity in DRG systems
Authors: Bäuml Matthias , Kümpel Christian
Published: December 2020

Many OECD countries have replaced per‐diem hospital reimbursement with lump sum payments by diagnosis‐related groups. This study analyzes hospital responses to a large‐scale refinement of reimbursement practices in Germany on January 1, 2006, in which regulating authorities introduce reimbursements by treatment intensity in the market for stroke disorder. We find that the share of admissions receiving high‐intensity treatments jumps by approximately 7 percentage points around the turn of the year. At the same time, a decrease in the average clinical severity of patients receiving these high‐intensity treatments reveals that the marginal high‐intensity treated patient in 2006 might be less appropriate for high‐intensity treatments compared to 2005. We do not find accompanying (short‐term) changes in the quality of care, such as decreases in in‐hospital mortality.
Is There Proof of Extraskeletal Benefits From Vitamin D Supplementation From Recent Mega Trials of Vitamin D?
Authors: Scragg Robert , Sluyter John D
Published: December 2020

Scientific interest in possible extraskeletal effects of vitamin D first appeared in the 1930s soon after the structure of vitamin D was characterized, and increased in the 1980s with the development of assays of 25‐hydroxyvitamin D status as a marker of vitamin D status, which in observational epidemiological studies was shown to be inversely associated with many nonskeletal diseases. This resulted in the start of seven large randomized controlled trials (n > 2000 participants in each) of vitamin D supplementation giving higher doses than previously used. The intervention periods in these trials collectively started in 2009 and continued to 2020. They have recruited participants, mostly of both sexes and over the age of 50 years, from many countries and have given either daily or monthly doses of vitamin D. Collectively, the trials have a wide range of outcomes with the main focus on the prevention of cancer, cardiovascular disease, and fractures, besides many other outcomes. The findings of four trials have been published, and they have shown that vitamin D supplementation does not prevent hard‐disease endpoints, such as cardiovascular disease, cancer, fractures, or falls, aside from a possible beneficial effect against cancer mortality. In contrast, beneficial effects were seen for intermediate outcomes such as BMD of spine and hips, arterial function, and lung function, especially in people with vitamin D deficiency. The finding of a benefit primarily in people with vitamin D deficiency, if confirmed by the other trials, would support a population approach to preventing vitamin D deficiency using fortification rather than the high‐risk approach of screening for deficiency combined with supplementation. The findings on other outcomes from the three published trials, along with the findings from the four unpublished trials, are expected within the next 2 to 3 years to clarify the role of vitamin D supplementation in preventing nonskeletal disease. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
Phase 1 Renal Impairment Trial Results Supports Targeted Individualized Dosing of ELX‐02 in Patients With Nephropathic Cystinosis
Authors: Haverty Thomas , Wyatt David J. , Porter Kaela M. , Leubitz Andi , Banks Kate , Goodyer Paul , Hu Ming‐Yi
Published: December 2020

The aim of this study was to assess the pharmacokinetics (PK) and safety of ELX‐02 in a renally impaired population and apply these findings to the individualized dosing of patients with nephropathic cystinosis. This phase 1 renal impairment (RI; mild, moderate, or severe), single‐dose, PK, and safety evaluation included 6 participants assigned to each RI group. Six healthy controls with normal renal function were matched to participants with renal impairment. All received a single subcutaneous dose of 1‐mg/kg ELX‐02 on day 1 and were monitored for 72 hours after dosing with serial blood and urine samples. An estimated glomerular filtration rate (eGFR)‐PK model of ELX‐02 was developed from the RI study data and used to implement individualized dosing in a phase 2a study in patients with nephropathic cystinosis to achieve a weekly targeted exposure (area under the plasma concentration–time curve [AUC]). In participants with RI, ELX‐02 clearance decreased, and exposure increased with severity of RI. ELX‐02 plasma exposure was similar to healthy controls in participants with mild RI, but increasing severity of RI resulted in significantly decreased clearance, increased maximum plasma concentration, AUC from time zero to infinity, and half‐life compared to controls. ELX‐02 urinary clearance showed a similar pattern. Relationships between eGFR and exposure were defined supporting individualized dose determination for prediction of dose and AUC in patients with nephropathic cystinosis, achieving overall mean 110.7% of AUC targets. ELX‐02 was well tolerated by RI and nephropathic cystinosis populations. ELX‐02 exhibits a consistent PK profile across increasing degrees of RI with reduced clearance, increased exposure, and prolonged renal elimination proportional to reductions in eGFR. The defined relationship between eGFR and plasma exposure enabled individualized dose adjustment in patients with nephropathic cystinosis.
Electrophysiological analysis of stimulus variables in equivalence relations
Authors: Dias Gustavo C. B. , Silveira Marcelo V. , Bortoloti Renato , Huziwara Edson M.
Published: December 2020

Recently, electrophysiological measures have been used to evaluate the functional overlap between semantic relations and laboratory‐defined equivalence relations with abstract stimuli. Several studies using semantic judgment procedures have shown that accompanying EEG‐measured neural activity for stimulus pairs from equivalence classes is very similar to that of word pairs from participants' native language. However, those studies often included pronounceable elements (e.g., written nonsense syllables) as at least one member of the experimentally defined classes. The present study conducted EEG studies that contrasted classes with and without such elements. Two groups of undergraduate students completed a matching‐to‐sample procedure to establish 3 4‐member equivalence classes. For Group 1, samples and comparisons were pronounceable pseudowords and abstract figures. For Group 2, the matching‐to‐sample stimuli were abstract figures only. EEG data recorded during the semantic judgment tasks showed waveform patterns compatible with prior studies of semantic relations in Group 1 but not in Group 2.
Assessing surface and subsurface transport of neonicotinoid insecticides from no‐till crop fields
Authors: Frame Sarah T. , Pearsons Kirsten A. , Elkin Kyle R. , Saporito Louis S. , Preisendanz Heather E. , Karsten Heather D. , Tooker John F.
Published: December 2020

Increased use of neonicotinoid‐coated crop seeds introduces greater amounts of insecticides into the environment, where they are vulnerable to transport. To understand the transport of neonicotinoids from agricultural fields, we planted maize (Zea mays L.) seeds coated with thiamethoxam in lysimeter plots in central Pennsylvania. Over the next year, we sampled water generated by rainfall and snowmelt and analyzed these samples with mass spectrometry for the neonicotinoids thiamethoxam and clothianidin (metabolite), which originated from the coated seeds. For surface and subsurface transport, thiamethoxam exhibited “first‐flush” dynamics, with concentrations highest during the first events following planting and generally decreasing for the remainder of the study. The metabolite clothianidin, however, persisted throughout the study. The mass of thiamethoxam and clothianidin exported during the study period accounted for 1.09% of the mass applied, with more than 90% of the mass transported in subsurface flow and less than 10% in surface runoff. These results suggest that surface runoff, at least for our site, is a relatively small contributor to the overall fate and transport of these insecticides and that the delivery ratio (i.e., mass exported/mass applied) observed for these compounds is similar to those of other trace‐level emerging contaminants known to negatively influence aquatic ecosystems.
Quantification of hemodynamics of cerebral arteriovenous malformations after stereotactic radiosurgery using 4D flow magnetic resonance imaging
Authors: Srinivas Shanmukha , Retson Tara , Simon Aaron , Hattangadi‐Gluth Jona , Hsiao Albert , Farid Nikdokht
Published: December 2020

Stereotactic radiosurgery (SRS) is used to treat cerebral arteriovenous malformations (AVMs). However, early evaluation of efficacy is difficult as structural magnetic resonance imaging (MRI)/magnetic resonance angiography (MRA) often does not demonstrate appreciable changes within the first 6 months. The aim of this study was to evaluate the use of four‐dimensional (4D) flow MRI to quantify hemodynamic changes after SRS as early as 2 months. This was a retrospective observational study, which included 14 patients with both pre‐SRS and post‐SRS imaging obtained at multiple time points from 1 to 27 months after SRS. A 3T MRI Scanner was used to obtain T2 single‐shot fast spin echo, time‐of‐flight MRA, and postcontrast 4D flow with three‐dimensional velocity encoding between 150 and 200 cm/s. Post‐hoc two‐dimensional cross‐sectional flow was measured for the dominant feeding artery, the draining vein, and the corresponding contralateral artery as a control. Measurements were performed by two independent observers, and reproducibility was assessed. Wilcoxon signed‐rank tests were used to compare differences in flow, circumference, and pulsatility between the feeding artery and the contralateral artery both before and after SRS; and differences in nidus size and flow and circumference of the feeding artery and draining vein before and after SRS. Arterial flow (L/min) decreased in the primary feeding artery (mean: 0.1 ± 0.07 vs. 0.3 ± 0.2; p < 0.05) and normalized in comparison to the contralateral artery (mean: 0.1 ± 0.07 vs. 0.1 ± 0.07; p = 0.068). Flow decreased in the draining vein (mean: 0.1 ± 0.2 vs. 0.2 ± 0.2; p < 0.05), and the circumference of the draining vein also decreased (mean: 16.1 ± 8.3 vs. 15.7 ± 6.7; p < 0.05). AVM volume decreased after SRS (mean: 45.3 ± 84.8 vs. 38.1 ± 78.7; p < 0.05). However, circumference (mm) of the primary feeding artery remained similar after SRS (mean: 15.7 ± 2.7 vs. 16.1 ± 3.1; p = 0.600). 4D flow may be able to demonstrate early hemodynamic changes in AVMs treated with radiosurgery, and these changes appear to be more pronounced and occur earlier than the structural changes on standard MRI/MRA. Level of Evidence: 4 Technical Efficacy Stage: 1
Relationship between clinical outcomes measures and personal and social performance functioning in a prospective, interventional study in schizophrenia
Authors: Vauth Roland , Carpiniello Bernardo , Turczyński Jacek , Ivanov Mikhail , Cherubin Pierre , Lahaye Marjolein , Schreiner Andreas
Published: December 2020

Objectives

To explore clinical and demographic characteristics impacting patient functioning by determining extent of overlap in factors driving change in Personal and Social Performance (PSP) and other clinical outcomes.

Methods

Post‐hoc analysis from a single‐arm trial of paliperidone extended release in adult patients with nonacute symptomatic schizophrenia. Psychosocial functioning measures: PSP, Clinical Global Impression–Severity (CGI‐S), Positive and Negative Syndrome Scale (PANSS), Short‐Form 36 (SF‐36), treatment satisfaction, sleep quality/daytime drowsiness, and Extrapyramidal Symptoms Rating Scale.

Results

Highest correlations with PSP total score change included PANSS total score change (Spearman's r = 0.607), PANSS general psychopathology change (r = 0.579), and CGI‐S change (r = 0.569). A PSP score change of −32 predicted 90% probability of deterioration in CGI‐S (score change of ≥1). The power of PSP change to predict PANSS total score change was lower. Linear stepwise regression demonstrated independent relationships for PSP change and: PANSS total change; CGI‐S change; SF‐36 Mental Component change; treatment satisfaction at endpoint; PSP at baseline; previous psychiatric hospitalizations. R
2 = 0.55 meant that 45% of PSP variation could not be explained by other clinical outcome measures.

Conclusions

Psychosocial functioning improvement is important in schizophrenia. PSP may be valuable for assessing functioning; it encompasses psychosocial and clinical factors not measured by other established assessments.
Improved preclinical hyperpolarized 129Xe ventilation imaging with constant flip angle 3D radial golden means acquisition and keyhole reconstruction
Authors: Niedbalski Peter J. , Cleveland Zackary I.
Published: December 2020

Hyperpolarized (HP) 129Xe MRI is increasingly used to noninvasively probe regional lung structure and function in the preclinical setting. As in human imaging, the primary barrier to quantitative imaging with HP gases is nonequilibrium magnetization, which is depleted by T1 relaxation and radio frequency excitation. Preclinical HP gas imaging commonly involves mechanically ventilating small animals and encoding k‐space over tens or hundreds of breaths, with small subsets of k‐space data collected within each breath. Breath‐to‐breath magnetization renewal enables the use of large flip angles, but the resulting magnetization decay generates large view‐to‐view differences in within‐breath signal intensity, leading to artifacts and degraded image quality. This deleterious signal decay has motivated the use of variable flip angle (VFA) sampling schemes, in which the flip angle is progressively increased to maintain constant view‐to‐view signal intensity. However, VFA imaging complicates data acquisition and provides only a global correction that fails to compensate for regional differences in signal dynamics. When constant flip angle (CFA) imaging is used alongside 3D radial golden means acquisition, the center of k‐space is sampled with every excitation, thereby encoding signal dynamics alongside imaging data. Here, keyhole reconstruction is used to generate multiple images to capture in‐breath HP 129Xe signal dynamics in mice and thus provide flip angle maps to quantitatively correct images without extra data collection. These CFA images display SNR that is not significantly different from VFA images, and further, high frequency k‐space scaling can be used to mitigate decay‐induced image artifacts. Results are supported by point spread function calculations and simulations of radial imaging with preclinical signal dynamics. Together, these results show that CFA 3D radial golden means ventilation imaging provides comparable image quality with VFA in small animals and allows for keyhole reconstruction, which can be used to generate flip angle maps and correct images for signal depletion.
Mental health shame, self‐compassion and sleep in UK nursing students: Complete mediation of self‐compassion in sleep and mental health
Authors: Kotera Yasuhiro , Cockerill Vicky , Chircop James G. E. , Forman Dawn
Published: December 2020

Aims

To explore relationships between mental health problems, mental health shame, self‐compassion and average length of sleep in UK nursing students. The increasing mental health problems in nursing students may be related to a strong sense of shame they experience for having a mental health problem. Self‐compassion has been identified as a protective factor for mental health and shame in other student populations. Further, studies highlight the importance of sleep relating to mental health.

Design

A cross‐sectional design.

Methods

A convenient sampling of 182 nursing students at a university in the East Midlands completed a paper‐based questionnaire regarding these four constructs, from February to April 2019. Correlation, regression and mediation analyses were conducted.

Results

Mental health problems were positively related to shame and negatively related to self‐compassion and sleep. Mental health shame positively predicted and self‐compassion negatively predicted mental health problems: sleep was not a significant predictor of mental health problems. Lastly, self‐compassion completely mediated the impacts of sleep on mental health problems (negative relationship between mental health problems and sleep was fully explained by self‐compassion).

Conclusion

The importance of self‐compassion was highlighted as it can reduce mental health problems and shame. Self‐compassion can protect nursing students from mental distress when they are sleep deprived.

Impact

Nurses and nursing students are required to work irregular hours (e.g. COVID‐19) and mental distress can cause serious consequences in clinical practice. Our findings suggest that nurturing self‐compassion can protect their mental health and the negative impacts of sleep deprivation on mental health.
Effects of different supercritical temperatures on the modification of aramid pulp surface via coating silica to enhance the properties of EPDM composites
Authors: Xu Qian , Kong Haijuan , Ding Haiquan , Zeng Juan , Jiang Feiyan , Du Xue , Li Biao , Yu Muhuo
Published: December 2020

Poor dispersion is a major disadvantage of aramid pulp (AP) reinforced composites. In this study, nano‐silica (SiO2), as the surface modifier and reinforcing agent, was synthesized on AP surfaces to improve the dispersed character in ethylene‐propylene‐diene elastomer (EPDM) using supercritical carbon dioxide (scCO2). The influence of the temperature of scCO2 on treated AP, configuration of the surface, and mechanical performance of AP/EPDM composites were studied. Based on the results of Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy, SiO2 was chemically grafted onto the AP surface. The SiO2 nanoparticles were uniformly deposited on the AP surface, and the roughness of AP was increased based on the SEM results. The optimum temperature of the supercritical reaction was 100°C considering the results of all the tests. Under the optimum temperature and with 10 phr of AP, the mechanical properties, oil resistance, and dynamic mechanical properties of the SiO2‐AP/EPDM composites were investigated. The tensile strength and tear strength of the SiO2‐AP/EPDM were improved by 121.1 and 134.9%, respectively, compared with that of the pure AP/EPDM composites. The fracture surface of the SiO2‐AP/EPDM composites showed that SiO2‐modified AP had a good dispersion in EPDM, and AP and EPDM had good interfacial bonding. Dynamic mechanical analysis results showed that the storage modulus of the composites was improved greatly compared with the pure AP/EPDM, and the loss factor also increased. The oil resistance of the composites was also improved.
Optimal routing strategy based on extreme learning machine with beetle antennae search algorithm for Low Earth Orbit satellite communication networks
Authors: Rajagopal Aghila , Ramachandran A. , Shankar K. , Khari Manju , Jha Sudan , Joshi Gyanendra Prasad
Published: December 2020

Due to the significant utilization of terrestrial communication, Low Earth Orbit (LEO) satellite network is a critical part of satellite communication networks owing to its several benefits. But the efficient and trustworthy routing for LEO satellite networks (LSNs) is a difficult process because of dynamic topology, adequate link changes, and imbalanced communication load. This study devises a new hybridization of extreme learning machine (ELM) with multitask beetle antennae search (MBAS) algorithm‐based distributed routing called the MBAS‐ELM model. The proposed model determines the routes based on traffic forecasting with respect to the level of traffic circulation on the earth. The proposed method is employed for traffic forecasting at the satellite nodes (SNs). To identify the optimal routes, mobile agents (MAs) are applied to concurrently and autonomously determine for LSNs and make a decision on routing data. The experimental outcome has showcased the effective performance of the proposed model over the compared models in terms of different measures, namely, average delay, packet loss ratio (PLR), and queuing delay. The results are validated under varying simulation time and data sensing rates. The obtained outcome pointed out the superior performance of the proposed MBAS‐ELM model compared with other methods.
Simultaneously Passivating Cation and Anion Defects in Metal Halide Perovskite Solar Cells Using a Zwitterionic Amino Acid Additive
Authors: Kim Ju‐Hyeon , Kim Yong Ryun , Park Byoungwook , Hong Soonil , Hwang In‐Wook , Kim Jehan , Kwon Sooncheol , Kim Geunjin , Kim Heejoo , Lee Kwanghee
Published: December 2020

Ionic defects (e.g., organic cations and halide anions), preferably residing along grain boundaries (GBs) and on perovskite film surfaces, are known to be a major source of the notorious environmental instability of perovskite solar cells (PeSCs). Although passivating ionic defects is desirable, previous approaches using Lewis base or acid molecules as additives suppress only the negatively or positively charged defects, thus leaving oppositely charged defects. In this work, both the cationic and anionic defects inside methyl ammonium lead tri‐iodide (MAPbI3) are simultaneously passivated by introducing a zwitterionic form of the amino acid, L‐alanine, into the precursor solution as an additive. L‐alanine has both positive (NH3+) and negative (COO−) functional groups at a specific solvent pH, thereby passivating both the cation and anion defects in MAPbI3. The addition of L‐alanine increases the grain size of the perovskite crystals and lengthens the charge carrier lifetime (τ > 1 µs), leading to improved power conversion efficiencies (PCEs) of 20.3% (from 18.3% without an additive) for small‐area (4.64 mm2) devices and 15.6% (from 13.5%) for large‐area submodules (9.06 cm2). More importantly, the authors’ approach also significantly enhances the shelf storage and photoirradiation stabilities of PeSCs.
Molecular Radiative Energy Shifts under Strong Oscillating Fields
Authors: Zheng Peng , Kang Jeeun , Paria Debadrita , Kang Jin U. , Barman Ishan
Published: December 2020

Coherent manipulation of light‐matter interactions is pivotal to the advancement of nanophotonics. Conventionally, the non‐resonant optical Stark effect is harnessed for band engineering by intense laser pumping. However, this method is hindered by the transient Stark shifts and the high‐energy laser pumping which, by itself, is precluded as a nanoscale optical source due to light diffraction. As an analog of photons in a laser, surface plasmons are uniquely positioned to coherently interact with matter through near‐field coupling, thereby, providing a potential source of electric fields. Herein, the first demonstration of plasmonic Stark effect is reported and attributed to a newly uncovered energy‐bending mechanism. As a complementary approach to the optical Stark effect, it is envisioned that the plasmonic Stark effect will advance fundamental understanding of coherent light‐matter interactions and will also provide new opportunities for advanced optoelectronic tools, such as ultrafast all‐optical switches and biological nanoprobes at lower light power levels.
Speciation and bioavailability studies of toxic metals in the alluvial soil of Onukun River floodplain in Okitipupa, Southwestern Nigeria
Authors: Aiyesanmi Ademola Festus , Oladele Mayowa Festus , Adelodun Adedeji Adebukola , Idowu Gideon Aina
Published: December 2020

We report on the speciation study of five toxic metals in the floodplain alluvial soils of Onukun river of Okitipupa, Ondo State, Nigeria. The bulk metal concentrations in the soil samples were in the order: Fe > Cr > Zn > Cu > Pb > Cd. Speciation analysis via sequential extraction was used to fractionate the metals into five operationally defined pools: exchangeable, carbonate, easily reducible, organic, and residual fractions. Generally, the organic, residual, and reducible fractions were the most abundant pools for Cu, Cr and Fe, Pb and Zn, respectively, whereas Cd was undetected. The soils were loamy sand, with pH and organic matter content ranging from 4.71% to 7.00% and 1.92% to– 4.62%, respectively. Furthermore, three pollution indices viz. geoaccumulation index, enrichment factor, and mobility/bioavailability evinced the trends: Fe > Cr > Zn > Cu > Pb, Cr > Zn > Cu > Fe > Pb, and Zn > Pb > Cu > Fe > Cr, respectively, with the pollution load index highest of 0.39. Conclusively, the floodplains’ soils are considered contaminated with the target toxic metals, necessitating their periodic monitoring and remediation.
Dual Pathway Model of Responses Between Climate Change and Livestock Production
Authors: Iyiola-Tunji Adetunji Oroye , Adamu James Ijampy , John Paul Apagu , Muniru Idris
Published: December 2020

This chapter was aimed at evaluating the responses of livestock to fluctuations in climate and the debilitating effect of livestock production on the environment. Survey of livestock stakeholders (farmers, researchers, marketers, and traders) was carried out in Sahel, Sudan, Northern Guinea Savannah, Southern Guinea Savannah, and Derived Savannah zones of Nigeria. In total, 362 respondents were interviewed between April and June 2020. The distribution of the respondents was 22 in Sahel, 57 in Sudan, 61 in Northern Guinea Savannah, 80 in Southern Guinea Savannah, and 106 in Derived Savannah. The respondents were purposively interviewed based on their engagement in livestock production, research or trading activities. Thirty-eight years’ climate data from 1982 to 2019 were obtained from Nigerian Metrological Agency, Abuja. Ilela, Kiyawa, and Sabon Gari were chosen to represent Sahel, Sudan, and Northern Guinea Savannah zone of Nigeria, respectively. The data contained precipitation, relative humidity, and minimum and maximum temperature. The temperature humidity index (THI) was calculated using the formula: THI = 0.8*T + RH*(T-14.4) + 46.4, where T = ambient or dry-bulb temperature in °C and RH=relative humidity expressed as a proportion. Three Machine Learning model were built to predict the monthly minimum temperature, maximum temperature, and relative humidity respectively based on information from the previous 11 months. The methodology adopted is to treat each prediction task as a supervised learning problem. This involves transforming the time series data into a feature-target dataset using autoregressive (AR) technique. The major component of the activities of livestock that was known to cause injury to the environment as depicted in this chapter was the production of greenhouse gases. From the respondents in this chapter, some adaptive measures were stated as having controlling and mitigating effect at reducing the effect of activities of livestock on the climate and the environment. The environment and climate on the other side of the dual pathway is also known to induce stress on livestock. The concept of crop-livestock integration system is advocated in this chapter as beneficial to livestock and environment in the short and long run. Based on the predictive model developed for temperature and relative humidity in a sample location (Ilela) using Machine Learning in this chapter, there is need for development of a web or standalone application that will be useable by Nigerian farmers, meteorological agencies, and extension organizations as climate fluctuation early warning system. Development of this predictive model needs to be expanded and made functional.
Studien(fach)wahlen: eine Frage der Motivlage?
Authors: Loge Lena
Published: December 2020

Im Wintersemester 2018/19 umfasste die Studierendenschaft in Deutschland 2 865 000 Immatrikulierte mit einem Frauenanteil von etwa 48,9 %. Wiederum 34,9 % der Studierenden waren an einer Fachhochschule bzw. einer Hochschule für Angewandte Wissenschaften eingeschrieben. An diesem speziellen Hochschultyp war der Frauenanteil mit 44,1 % außerdem geringer als an Universitäten bzw. hochschulübergreifend.
Studien(fach)wahlen und ihre Ursachen: an der Schnittstelle von Geschlechterforschung und Bildungsforschung
Authors: Loge Lena
Published: December 2020

Was berufs- und arbeitsbezogene Orientierungsmuster von Frauen angeht, lohnt sich der Rückblick auf die frühe Frauen- und Geschlechterforschung: In den 1980er-Jahren standen insbesondere die strukturellen Ungleichheiten zwischen den Geschlechtern im Fokus und es wurde ein differenzbetonender Blick auf den „weiblichen Lebenszusammenhang“ gelegt, also auf die von Frauen ausgeübte unbezahlte Arbeit und schlecht bezahlte Lohnarbeit, ihre alleinige Sorge für Kinder und die fehlende Repräsentation in Politik und Gesellschaft. Die „doppelte Vergesellschaftung“ von Frauen hinsichtlich Erwerbs- und Familienarbeit, das Konzept des „weiblichen Arbeitsvermögens“ und das empirische Infragestellen der „weiblichen Familienorientierung“ waren Kernelemente der berufsbezogenen Frauenforschung zu dieser Zeit.
Methodologie und methodisches Vorgehen
Authors: Loge Lena
Published: December 2020

In der vorliegenden Untersuchung wurde auf Grundlage der dargestellten theoretischen Verknüpfungen der Frage nachgegangen, wie sich Studien(fach)wahlen im Kontext von sozialem Milieu und Geschlecht konstituieren. Um dieser Frage nachzugehen, wurde ein qualitativer Zugang gewählt: Im Gegensatz zu quantitativer Forschung wurden keine vordefinierten Hypothesen an den Forschungsgegenstand herangetragen, die überprüft werden sollten. Stattdessen bietet sich ein qualitatives Vorgehen an, um theoriegeleitet offene Fragestellungen zu verfolgen und das beforschte Feld möglichst umfassend zu ‚verstehen‘
Von Sozialarbeitern und Bauingenieurinnen: Habitushermeneutische Fallanalysen
Authors: Loge Lena
Published: December 2020

Die Terminvereinbarung mit Sonja ist mit einer sehr zuverlässigen Kommunikation ihrerseits verbunden: Als einzige Interviewpartnerin bestätigt sie einen Tag vor dem Gespräch den Termin proaktiv per Email und schreibt, sie hoffe „etwas Nützliches“ erzählen zu können. Damit betont sie die Relevanz ihrer Rolle als Befragte für das Forschungsvorhaben und begibt sich mit der Forscherin im Vornerein auf Augenhöhe. Dieser Eindruck setzt sich in der Interviewsituation fort: Bevor die Aufnahme gestartet wird, stellt Sonja einige Fragen zum Anliegen und zur Methode des Forschungsprojekts.
Ergebnisse: Studien(fach)wahlen im Kontext von sozialem Milieu und Geschlecht
Authors: Loge Lena
Published: December 2020

Die analysierten Wege in das Bauingenieurwesen und die Soziale Arbeit zeigen, wie Studien(fach)wahlen eingebettet sind in die vergeschlechtlichte milieuspezifische Lebensführung und wie die antizipierte Passung zu einem Studienfach und einem Beruf in diesem Zusammenspiel entsteht. Je nach vergeschlechtlichter milieuspezifischer Habitualisierung werden die Handlungsmöglichkeiten auf dem Weg in einen Beruf kanalisiert bzw. erweitert, bestimmte Dispositionen werden gestärkt und andere in den Hintergrund gerückt. Was das Verhältnis der Fälle zueinander angeht, haben sich Ähnlichkeiten und Kontraste in den Analysen bereits angedeutet und bilden sich ebenso in ihrer Verortung im Modell sozialer Milieus ab.
Schluss und Ausblick: komplexe Passungsverhältnisse
Authors: Loge Lena
Published: December 2020

Ziel der vorliegenden Arbeit war es, die Erkenntnisse von Geschlechter- und Bildungsforschung zu Studien(fach)wahlen miteinander zu verknüpfen und in der Analyse die Dimensionen von sozialer Herkunft und Geschlecht systematisch zu verbinden. So sollte die Frage beantwortet werden, wie die Wahl eines Studiums und Studienfachs vor dem Hintergrund von sozialem Milieu und Geschlecht zu verstehen und zu erklären ist. Die Ergebnisse werden in diesem Kapitel zusammengefasst.
Komplexität im Projektmanagement
Authors: Harlacher Markus , Nitsch Verena , Mütze-Niewöhner Susanne
Published: December 2020

Aus der Diskussion um die Veränderungen in der Arbeitswelt ist der Begriff der Komplexität nicht mehr wegzudenken. Der Beitrag befasst sich mit diesem Phänomen im Kontext der Projektarbeit. Der Fokus liegt dabei auf dem Projektmanagement und den mit dieser Aufgabe betrauten Personen. Die Autoren nehmen damit eine Zielgruppe in den Fokus, die sich häufig hohen Belastungen ausgesetzt sieht. Im Beitrag werden die Ergebnisse einer Online-Befragung mit 50 Projektmanager*innen zur Bewertung von Komplexitätsindikatoren hinsichtlich ihrer praktischen Relevanz für die Projektmanagementkomplexität vorgestellt. Die Ergebnisse zeigen, dass sich die Mehrzahl der als komplexitätstreibend eingestuften Indikatoren auf organisatorische Gestaltungsaspekte bezieht. Die höchste Relevanz wird dabei Faktoren zugesprochen, die die Widersprüchlichkeit und Veränderlichkeit von Zielen, Anforderungen und Regularien betreffen. Die Untersuchung liefert außerdem Hinweise darauf, dass Projektmanagementkomplexität in Abhängigkeit des Managementansatzes (klassisch, hybrid, agil) betrachtet werden sollte. Unterschiede in der Beurteilung ergeben sich zum Beispiel in Bezug auf Zeitdruck, Leistungsdruck und Anzahl an Kunden.