bluuebunny/crossref_metadata_2025 huggingface dataset:
Phylogenetic comparative morphological analysis of fern spores in subfamily Pteridoideae (Pteridaceae, Pteridophyta)
Authors: Vaganov Alexey V.
Published: September 2021

Scanning electron microscopy (SEM) was used to characterize spore morphology of 24 taxa of the subfamily Pteridoideae C. Chr. ex Crabbe, Jermy & Mickel of the family Pteridaceae E.D.M. Kirchn. The family is considered to be one of the most taxonomically confusing families due to its high level of polymorphism. The standardized data on spore morphology of the subfamily Pteridoideae were projected onto the final phylogenetic tree in the Mesquite program. This approach made it possible to carry out a comprehensive interdisciplinary analysis of the evolution of spore morphology characters of the subfamily Pteridoideae, as well as to assess the relationships in the family Pteridaceae. The equatorial ridge (cingulum, “flange”) has been proven as one of the key spore morphology features, which confirms the close relationship of “Onychium clade” with Pteris. The species‐specific characters of the subfamily are fold and tubercle along laesura, equatorial ridge on proximal and distal side, tubercle, and folds on proximal and distal side. The knowledge will help to solve the problems of taxonomy in the family Preridaceae and to supplement the information on the natural classification of the subfamily Pteridoideae.
COVID‐19 disease in hospitalized young adults in India and China: Evaluation of risk factors predicting progression across two major ethnic groups
Authors: Panda Smriti , Roy Sankanika , Garg Rohit K. , Hui Gan , Gorard Jack , Bhutada Mayank , Sun Yuanli , Bhatnagar Sushma , Mohan Anant , Dar Lalit , Liu Mao
Published: September 2021

Data pertaining to risk factor analysis in coronavirus disease 2019 (COVID‐19) is confounded by the lack of data from an ethnically diverse population. In addition, there is a lack of data for young adults. This study was conducted to assess risk factors predicting COVID‐19 severity and mortality in hospitalized young adults. A retrospective observational study was conducted at two centers from China and India on COVID‐19 patients aged 20–50 years. Regression analysis to predict adverse outcomes was performed using parameters including age, sex, country of origin, hospitalization duration, comorbidities, lymphocyte count, and National Early Warning Score 2 (NEWS2) score at admission. A total of 420 patients (172 East Asians and 248 South Asians) were included. The predictive model for intensive care unit (ICU) admission with variables NEWS2 Category II and higher, diabetes mellitus, liver dysfunction, and low lymphocyte counts had an area under the curve (AUC) value of 0.930 with a sensitivity of 0.931 and a specificity of 0.784. The predictive model for mortality with NEWS2 Category III, cancer, and decreasing lymphocyte count had an AUC value of 0.883 with a sensitivity of 0.903 and a specificity of 0.701. A combined predictive model with bronchial asthma and low lymphocyte count, in contrast, had an AUC value of 0.768 with a sensitivity of 0.828 and a specificity of 0.719 for NEWS2 score (5 or above) at presentation. NEWS2 supplemented with comorbidity profile and lymphocyte count could help identify hospitalized young adults at risk of adverse COVID‐19 outcomes.
Point‐of‐CareUltrasound Predicts Clinical Outcomes in Patients WithCOVID‐19
Authors: Kumar Andre , Weng Isabel , Graglia Sally , Lew Thomas , Gandhi Kavita , Lalani Farhan , Chia David , Duanmu Youyou , Jensen Trevor , Lobo Viveta , Nahn Jeffrey , Iverson Nicholas , Rosenthal Molly , Gordon Alexandra June , Kugler John
Published: September 2021

Objectives

Point‐of‐care ultrasound (POCUS) detects the pulmonary manifestations of COVID‐19 and may predict patient outcomes.

Methods

We conducted a prospective cohort study at four hospitals from March 2020 to January 2021 to evaluate lung POCUS and clinical outcomes of COVID‐19. Inclusion criteria included adult patients hospitalized for COVID‐19 who received lung POCUS with a 12‐zone protocol.

Each image was interpreted by two reviewers blinded to clinical outcomes. Our primary outcome was the need for intensive care unit (ICU) admission versus no ICU admission. Secondary outcomes included intubation and supplemental oxygen usage.

Results

N = 160 patients were included. Among critically ill patients, B‐lines (94 vs 76%;P < .01) and consolidations (70 vs 46%;P < .01) were more common. For scans collected within 24 hours of admission (N = 101 patients), early B‐lines (odds ratio [OR] 4.41 [95% confidence interval, CI: 1.71–14.30];P < .01) or consolidations (OR 2.49 [95% CI: 1.35–4.86];P < .01) were predictive of ICU admission. Early consolidations were associated with oxygen usage after discharge (OR 2.16 [95% CI: 1.01–4.70];P = .047). Patients with a normal scan within 24 hours of admission were less likely to require ICU admission (OR 0.28 [95% CI: 0.09–0.75];P < .01) or supplemental oxygen (OR 0.26 [95% CI: 0.11–0.61];P < .01). Ultrasound findings did not dynamically change over a 28‐day scanning window after symptom onset.

Conclusions

Lung POCUS findings detected within 24 hours of admission may provide expedient risk stratification for important COVID‐19 clinical outcomes, including future ICU admission or need for supplemental oxygen. Conversely, a normal scan within 24 hours of admission appears protective. POCUS findings appeared stable over a 28‐day scanning window, suggesting that these findings, regardless of their timing, may have clinical implications.
Autologous fat grafting in the face and neck: Multinational trends and knowledge of the safety, applications, and indications considering oncologic risk potential
Authors: Fiedler Lukas S , Saleh Daniel B , Mukrowsky Alicia
Published: September 2021

Background

Autologous fat grafting (AFG) is evolving in both aesthetic and reconstructive applications, since the body of evidence for its use has expanded. The earliest controversies were evident in lipofilling for oncological breast reconstruction, and to this day, some countries do not allow it for fear of inducing tumourigenesis in an oncologically ablated field.

Methods

We sought to review contemporary harvesting and processing techniques for AFG in the craniofacial region, therefore distributed a survey to evaluate the clinical impact of oncological risk across four European countries.

Results

We found no significant geographical differences between the German‐speaking and the English groups concerning their harvesting and processing technique. Half of our respondents discuss the possibility of pro‐oncologic behavior of AFG.

Conclusion

AFG harvesting and processing techniques do not considerably vary by geography. Further studies should evaluate oncologic risk potential of AFG in head and neck tumor sites, especially because there is no excellent article regarding this phenomenon.

Level of Evidence: V
Thermal Induced Polymerization of l‐Lysine forms Branched Particles with Blue Fluorescence
Authors: Stagi Luigi , Malfatti Luca , Caboi Francesca , Innocenzi Plinio
Published: September 2021

The polycondensation of amino acids can originate complex polymers that display fascinating structural and optical properties. Thermally induced amidation of l‐lysine allows forming a branched polymer without the support of any catalyst. The polycondensation is completed at 240–250 °C; at higher temperatures, the amino acid degrades. The obtained polylysine particles have been studied by transmission electron microscopy (TEM), nuclear magnetic resonance, and infrared spectroscopy that allow for investigating the different steps of the synthesis. The resulting structure is characterized by peculiar optical properties, e.g., excitation‐dependent blue fluorescence and good quantum efficiency. Hydrogen bonds and the interactions of the amino acids are considered responsible for the optical properties of both l‐lysine monomer solutions at high concentrations and the branched nanopolymers.
Two‐linked periodic Sturm–Liouville problems with transmission conditions
Authors: Mukhtarov Oktay Sh. , Aydemir Kadriye
Published: August 2021

The aim of this study is to generalize some important spectral properties of classical periodic Sturm–Liouville problems to two‐linked periodic problems with additional transmission conditions at an interior point of interaction, which have not been studied previously. Although the classical periodic Sturm–Liouville problem has infinitely many real eigenvalues, there are two‐linked periodic Sturm–Liouville problems that have only a finite number of real eigenvalues. To show this, we construct a simple example of two‐linked periodic Sturm–Liouville problem with transmission conditions having only one real eigenvalue. Using our own approach, we define the characteristic determinant of a new type, find simple conditions on the coefficients of the transmission conditions that guarantee the existence of an infinite number of real eigenvalues, and derive an asymptotic formula for the eigenvalues.
Environment considerations on the spread of rabies among African wild dogs (Lycaon pictus) with control measures
Authors: Chapwanya Michael , Dumani Phindile
Published: August 2021

Wildlife conservation is crucial in preventing endangered species from becoming extinct, and disease outbreaks is one of the biggest threats. Rabies is one of the devastating viruses that can almost be impossible to control once an outbreak occurs. There is no effective treatment or cure of rabies once symptoms show. In this work, we propose euthanasia of infected Lycaon pictus dogs as a control strategy to reduce the spread of the virus. We propose a simple deterministic SEI‐type rabies model that takes into account the contaminated environment and the euthanasia of infectious dogs to better understand the transmission and progression dynamics of the disease, as well as to seek to predict the effectiveness of this control strategy. Qualitative analysis and numerical simulations are provided to support our findings.
Liver DCE‐MRI registration based on sparse recovery of contrast agent curves
Authors: Sun Yuhang , Zhu Qiaoyun , Huang Meiyan , Shen Dinggang , Zhou Yujia , Feng Qianjin
Published: August 2021

Purpose

Dynamic contrast‐enhanced MRI (DCE‐MRI) registration is a challenging task because of the effect of remarkable intensity changes caused by contrast agent injections. Unrealistic deformation usually occurs by using traditional intensity‐based algorithms. To alleviate the effect of contrast agent on registration, we proposed a DCE‐MRI registration strategy and investigated the registration performance on the clinical DCE‐MRI time series of liver.

Method

We reconstructed the time–intensity curves of the contrast agent through sparse representation with a predefined dictionary whose columns were the time–intensity curves with high correlations with respect to a preselected contrast agent curve. After reshaping 1D‐reconstructed contrast agent time–intensity curves into a 4D contrast agent time series, we aligned the original time series to the reconstructed contrast agent time series through traditional free‐form deformation (FFD) registration scheme combined with a residual complexity (RC) similarity and an iterative registration strategy. This study included the DCE‐MRI time series of 20 patients with liver cancer.

Results

Qualitatively, the time‐cut images and subtraction images of different registration methods did not obviously differ. Quantitatively, the mean (standard deviation) of temporal intensity smoothness of all the patients achieved 54.910 (18.819), 54.609 (18.859), and 53.391 (19.031) in FFD RC, RDDR, Zhou et al.’s method and the proposed method, respectively. The mean (standard deviation) of changes in the lesion volume were 0.985 (0.041), 0.983 (0.041), 0.981 (0.046), and 0.989 (0.036) in FFD RC, RDDR, Zhou et al.’s method and the proposed method.

Conclusion

Our proposed method would be an effective registration strategy for DCE‐MRI time series, and its performance was comparable with that of three advanced registration methods.
Magnetic microspheres can be used for magnetic particle imaging of cancer cells arrested in the mouse brain
Authors: Melo Kierstin P. , Makela Ashley V. , Knier Natasha N. , Hamilton Amanda M. , Foster Paula J.
Published: August 2021

Purpose

Magnetic particle imaging (MPI) is a new imaging modality that sensitively and specifically detects superparamagnetic iron oxide nanoparticles (SPIOs). MRI cell tracking with SPIOs has very high sensitivity, but low specificity and quantification is difficult. MPI could overcome these limitations. There are no reports of micron‐sized iron oxide particles (MPIO) for cell tracking by MPI. Therefore, the goal was to evaluate if MPIO can be used for in vivo detection and quantification of cancer cells distributed in the mouse brain by MPI.

Methods

In the first experiment mice were injected with either 2.5 × 105 or 5.0 × 105 MPIO‐labeled cancer cells and MPI was performed ex vivo. In a second experiment, mice received either 2.5 × 105 or 5.0 × 104 MPIO‐labeled cells and MPI was performed in vivo. In a third experiment, mice were injected with 5.0 × 104 cells, labeled with either MPIO or ferucarbotran, and MPI was performed in vivo.

Results

MPIO‐labeled cells were visible in all MPI images of the mouse brain. The MPI signal and iron content measurements were greater for brains of mice that were injected with higher numbers of MPIO‐labeled cells. Ferucarbotran‐labeled cells were not detected in the brain by MPI.

Conclusion

This is the first example of the use of MPIO for cell tracking with MPI. With an intracardiac cell injection, ~15% of cells will arrest in the brain vasculature. For our lowest cell injection of 5.0 × 104 cells, this was ~10 000 cells, distributed throughout the brain.
Ultrasonic spray coating of polyethylenimine (ethoxylated) as electron injection and transport layer for organic light emitting diodes: The influence of layer morphology and thickness on the interface physics between polyethylenimine (ethoxylated) and the Al cathode
Authors: Verboven Inge , Nithyanandakumar Rachith Shanivarasanthe , Van Landeghem Melissa , Pellaers Hilde , Ruttens Bart , D'Haen Jan , Vandewal Koen , Deferme Wim
Published: September 2021

Modern lighting is expected to be light weight, flexible, efficient, non‐expensive and environmentally friendly fabricated. Organic light emitting diodes (OLEDs) meet all these requirements and can be manufactured using inexpensive and roll‐to‐roll compatible printing techniques. They, however, often use low work function, highly reactive metals, such as barium and calcium to facilitate electron injection, deposited using expensive and non‐continuous vacuum techniques. Efficient and stable alternatives can be found in the aliphatic amines, polyethylenimine (PEI) and polyethylenimine(ethoxylated) (PEIE), that shift the work function of aluminum favorably for electron injection. This work demonstrates ultrasonic spray coating of PEI(E) as electron injection and transport layer for OLEDs, reducing the work function of the aluminum cathode by 0.355 eV allowing a luminous efficacy comparable to that of the OLEDs using calcium/aluminum electrodes. Slightly higher luminous results are noted for the OLEDs with spin coated PEI(E), indicating that the surface morphology and thickness of the PEI(E) layer are crucial factors: ultrasonic spray coated PEI(E) layers have an increased overall thickness and surface roughness. This study shows the potential of ultrasonic spray coating and the suitability of PEI(E) as excellent electron injection and transport layer for OLEDs and paves the way towards fully spray coated OLEDs.
Challenges in parenteral nutrition in adult ultrashort gut: A case of cachexia
Authors: Russell Lindsey , Gramlich Leah
Published: September 2021

Patients with ultrashort gut have inadequate nutrient absorption. Parenteral nutrition (PN) is required to meet nutrition requirements caused by chronic intestinal failure (IF). We present a case of cachexia and IF caused by ultrashort gut following an extensive small‐bowel resection caused by volvulus that was complicated by small‐bowel ischemia. Targeting energy prescriptions to optimize PN using indirect calorimetry in this population with ultrashort gut has not been reported in adults. This case serves to outline the challenges in optimizing PN, including factors such as anabolic status, to meet nutrition requirements in patients with ultrashort gut and cachexia.
Differences in metabolic syndrome indicators by body mass index of women with endometriosis
Authors: Park SoMi , Chung ChaeWeon
Published: September 2021

Aim

The study aimed to identify the relationships between metabolic syndrome indicators and BMI in women with endometriosis.

Design

A retrospective observational study design was utilized to analyse secondary data from a longitudinal dataset.

Methods

A total of 281,810 women diagnosed with endometriosis and aged 15 through 49 were drawn from the National Health Insurance Service‐National Health Screening Cohort data of the Republic of Korea from the year 2009 to 2016. Body mass index (BMI) and five indicators of metabolic syndrome were extracted. Descriptive statistics, Cochran–Mantel–Haenszel test, chi‐square test and Cochran‐Armitage test were used.

Results

Yearly changes in abnormal waist circumference, elevated fasting blood sugar and abnormally low levels of high‐density lipoprotein cholesterol were statistically significant. The risk groups of these indicators all showed statistically significant differences according to BMI. The proportions of women with abnormal findings for all indicators significantly increased as BMI increased.
Coupled and decoupled high‐order accurate dissipative finite difference schemes for the dissipative generalized symmetric regularized long wave equations
Authors: He Yuyu , Wang Xiaofeng , Dai Weizhong
Published: August 2021

In this paper, two coupled and decoupled dissipative finite difference schemes with high‐order accuracy are proposed for solving the dissipative generalized symmetric regularized long wave equations. Dissipation of the discrete energy of scheme with different parameters is discussed. A priori estimate, existence and uniqueness of numerical solutions, convergence with and stability of the schemes are proved by the discrete energy method. Numerical examples are given to support the theoretical analysis.
Regional and sociodemographic differences in average BMI among US children in the ECHO program
Authors: Bekelman Traci A. , Dabelea Dana , Ganiban Jody M. , Law Andrew , McGovern Reilly Alexandra , Althoff Keri N. , Mueller Noel , Camargo Carlos A. , Duarte Cristiane S. , Dunlop Anne L. , Elliott Amy J. , Ferrara Assiamira , Gold Diane R. , Hertz‐Picciotto Irva , Hartert Tina , Hipwell Alison E. , Huddleston Kathi , Johnson Christine C. , Karagas Margaret R. , Karr Catherine J. , Hershey Gurjit K. Khurana , Leve Leslie , Mahabir Somdat , McEvoy Cindy T. , Neiderhiser Jenae , Oken Emily , Rundle Andrew , Sathyanarayana Sheela , Turley Christine , Tylavsky Frances A. , Watson Sara E. , Wright Rosalind , Zhang Mingyu , Zoratti Edward ,   program collaborators for Environmental influences on Child Health Outcomes (ECHO)
Published: September 2021

Objective

The aim of this study was to describe the association of individual‐level characteristics (sex, race/ethnicity, birth weight, maternal education) with child BMI within each US Census region and variation in child BMI by region.

Methods

This study used pooled data from 25 prospective cohort studies. Region of residence (Northeast, Midwest, South, West) was based on residential zip codes. Age‐ and sex‐specific BMI z scores were the outcome.

Results

The final sample included 14,313 children with 85,428 BMI measurements, 49% female and 51% non‐Hispanic White. Males had a lower average BMI z score compared with females in the Midwest (β = −0.12, 95% CI: −0.19 to −0.05) and West (β = −0.12, 95% CI: −0.20 to −0.04). Compared with non‐Hispanic White children, BMI z score was generally higher among children who were Hispanic and Black but not across all regions. Compared with the Northeast, average BMI z score was significantly higher in the Midwest (β = 0.09, 95% CI: 0.05 to 0.14) and lower in the South (β = −0.12, 95% CI: −0.16 to −0.08) and West (β = −0.14, 95% CI: −0.19 to −0.09) after adjustment for age, sex, race/ethnicity, and birth weight.

Conclusions

Region of residence was associated with child BMI z scores, even after adjustment for sociodemographic characteristics. Understanding regional influences can inform targeted efforts to mitigate BMI‐related disparities among children.
Generation of ductal organoids from normal mammary luminal cells reveals invasive potential
Authors: Ganz Hilary M , Buchmann Benedikt , Engelbrecht Lisa K , Jesinghaus Moritz , Eichelberger Laura , Gabka Christian J , Schmidt Georg P , Muckenhuber Alexander , Weichert Wilko , Bausch Andreas R , Scheel Christina H
Published: September 2021

Here we present an experimental model for human luminal progenitor cells that enables single, primary cells isolated from normal tissue to generate complex branched structures resembling the ductal morphology of low‐grade carcinoma of no special type. Thereby, we find that ductal structures are generated through invasive branching morphogenesis via matrix remodeling and identify reduced actomyosin contractility as a prerequisite for invasion. In addition, we show that knockout of E‐cadherin causes a dissolution of duct formation as observed in invasive lobular carcinoma, a subtype of invasive carcinomas where E‐cadherin function is frequently lost. Thus, our model shows that invasive capacity can be elicited from normal luminal cells in specific environments, which results in low‐grade no special type morphology. This assay offers a platform to investigate the dynamics of luminal cell invasion and unravel the impact of genetic and non‐genetic aberrations on invasive morphology. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
Vertebroplasty as a palliative treatment option for intractable pain in pediatric patients with spinal tumors
Authors: Cardarelli‐Leite Leandro , Rassekh Shahrad Rod , D'Ortenzio Robert , Heran Manraj Kanwal Singh
Published: August 2021

Primary and secondary malignant tumors of the spine are relatively uncommon in the pediatric population but are associated with high morbidity and significantly decreased quality of life due to pain. Local management of these tumors is often challenging due to the importance of maintaining vertebral mechanical integrity as well as the spinal growth potential. Typically, surgery and/or radiation therapy have been used in the primary management of these tumors. However, treatment options become more limited when there is relapse or refractory disease, with re‐resection or additional radiotherapy often not being viable therapies. Vertebroplasty is a currently underutilized modality that might provide significant pain palliation in cases of relapsed cancer in the spine.
Screening and characterisation of potential antioxidant, hypoglycemic and hypolipidemic components revealed in Portulaca oleracea via multi‐target affinity ultrafiltration LC–MS and molecular docking
Authors: Zhang Hui , Chen Guilin , Yang Jinpeng , Yang Chunlei , Guo Mingquan
Published: September 2021

Introduction

Portulaca oleracea is a commonly used nutritional vegetable and traditional herbal medicine with plenty of nutrients and manifold pharmacological activities. However, the potential active ingredients for its remarkable antioxidant, hypoglycemic and hypolipidemic activities remain unexplored.

Objectives

The present study aims to systematically evaluate the antioxidant activities of different extracts of P. oleracea and screen bioactive ligands that can interact with α‐glucosidase, pancreatic lipase, and superoxide dismutase (SOD).

Methods

In this research, the antioxidant activities of different parts of P. oleracea and their corresponding total phenolic content (TPC) and total flavonoid content (TFC) were systematically determined. Subsequently, a multi‐target affinity ultrafiltration method was developed using affinity ultrafiltration with SOD, α‐glucosidase, and pancreatic lipase coupled to liquid chromatography–mass spectrometry (UF‐LC–MS). Later, molecular docking was used to further investigate the possible interaction mechanism between these ligands and target enzymes.

Results

Among them, the ethyl acetate (EA) fraction showed the highest antioxidant activity along with the highest TPC and TFC, and four compounds in the EA fraction were quickly retrieved as potential SOD, α‐glucosidase, and pancreatic lipase ligands, respectively. Molecular docking revealed that these potential ligands exhibited strong binding ability and inhibitory activities on SOD, α‐glucosidase, and pancreatic lipase.

Conclusion

The present study revealed that P. oleracea can be used as a functional food with excellent antioxidant, hypoglycemic and hypolipidemic effects. Meanwhile, the integrated strategy based on multi‐target UF‐LC–MS and molecular docking also provided a powerful tool and a multidimensional perspective for further exploration of active ingredients in P. oleracea responsible for the antioxidant, hypoglycemic and hypolipidemic activities.
Menschen sicher leiten und evakuieren
Authors: Schadschneider Andreas , Seyfried Armin
Published: September 2021

Um in der Zukunft Unglücke wie bei der Loveparade zu vermeiden, müssen solche Großveranstaltungen sorgfältig geplant werden. Dabei können physikbasierte Modelle der Fußgängerdynamik helfen. In den letzten Jahren sind hier große Fortschritte erzielt worden, die solche Anwendungen in naher Zukunft routinemäßig möglich machen werden. Diese Maßnahmen helfen allerdings nur, wenn sich die Leute an die Regeln halten. Dies ist leider nicht immer der Fall, wie Unglücke in den letzten Jahren zeigen. Beim Haddsch kam es trotz vieler Verbesserungen zu weiteren Unglücken, vermutlich weil Pilger in die falsche Richtung gelaufen sind. Da es sich in dem System um Menschen handelt, deren Verhalten auf einem komplexen Reiz‐Reaktionsmechanismus aufbaut, die in sozialen Gruppen agieren und die sich in vielfältigen physischen und psychischen Faktoren unterscheiden, erfordert dieses Thema eine große Offenheit für interdisziplinäre Kooperationen. Trotzdem ist es erstaunlich, dass sich viele der beobachteten Phänomene in Menschenmengen ohne tiefere Berücksichtigung von psychologischen Aspekten gut beschreiben lassen. Dies entspricht den Erfahrungen, die man in der statistischen Physik mit Vielteilchensystemen gemacht hat, bei denen oftmals Details keine Rolle spielen. Dies trifft natürlich nicht mehr zu, wenn man das Verhalten von wenigen Personen beschreiben möchte. Dies ist viel mehr durch Psychologie als durch die Physik bestimmt.
Wieviel Planck‐Konstante steckt im Kilogramm?
Authors: Rothleitner Christian
Published: September 2021

Die Einheit der Masse im Internationalen Einheitensystem (SI) ist das Kilogramm. Auf der 26. Generalkonferenz für Maß und Gewicht (CGPM) im November 2019 wurde beschlossen, dass die Definition nicht länger das Urkilogramm sein wird, sondern der numerische Wert der Planck‐Konstante. Seit dem 20. Mai 2019 ist dies gültig. Nur zwei Experimente sind in der Lage, das Kilogramm aus seiner neuen Definition darzustellen. Eines davon ist die Kibble‐Waage, mit der die Gewichtskraft eines Gewichtstückes mit einer elektromagnetischen Kraft im Gleichgewicht gehalten wird. Die besten Geräte erreichten dabei bereits eine relative Messunsicherheit unterhalb von 2 ·10–8.
Was begrenzt das Leben?
Authors: Kleidon Axel
Published: September 2021

Seit langer Zeit ist gut dokumentiert, dass die Photosynthese mit einem sehr geringen Wirkungsgrad von weniger als 3 % aus Sonnenlicht chemische Energie gewinnt. Aber warum ist der Prozess so ineffizient? Schließlich hatte die Photosynthese mehr als drei Milliarden Jahre in der Erdgeschichte Zeit, sich zu optimieren. Diese Frage wird hier mit dem geringen, aber thermodynamisch limitierten Gasaustausch zwischen Pflanzen und Atmosphäre erklärt. Während des Tages müssen Pflanzen der Atmosphäre Kohlendioxid entziehen, den Rohstoff für die Photosynthese. Dabei verlieren sie unvermeidbar große Mengen an Wasserdampf, verbunden mit ihrer Transpiration. Folglich sind Kohlendioxidaufnahme und Wasserdampfabgabe eng miteinander verbunden. Eine einfache Abschätzung zeigt, dass dieser Massenaustausch zwischen Erdoberfläche und Atmosphäre thermodynamisch limitiert ist. Sie kann die geringe Effizienz der Photosynthese schlüssig erklären.
Zerstörungsfreie Verfolgung eines einzelnen Photons
Authors: Welte Stephan , Distante Emanuele , Rempe Gerhard
Published: September 2021

Alle konventionellen Einzelphotonendetektoren zerstören die Photonen beim Detektionsprozess. Diese Limitierung kann durch neuartige nicht‐destruktive Detektoren überwunden werden. Unserer Gruppe am Max‐Planck‐Institut für Quantenoptik ist es nun gelungen, zwei solche nichtdestruktive Detektoren hintereinanderzuschalten, um ein einzelnes Photon bei seinem Flug durch eine Glasfaser zu verfolgen. Durch die mehrfache Detektion wird sowohl die Detektionseffizienz als auch das Signal‐Rausch‐Verhältnis stark verbessert. In einem Quantennetzwerk könnte die Technik für die orts‐ und zeitaufgelöste Überwachung einzelner Photonen verwendet werden.
Wigner‐Kristall in zweidimensionalen Halbleitern
Authors: Kroner M. , Smoleński T. , Demler E. , Imamoğlu A.
Published: September 2021

In einem zweidimensionalen Halbleiter können Elektronen aufgrund ihrer abstoßenden Wechselwirkung in einen regulären Wigner‐Kristall kondensieren. Dieser elektronische Kristall kann mittels resonanter optischer Spektroskopie nachgewiesen werden.
Smarte Waage mit Barometer & Altimeter Pro
Authors: Peter Stefanie , Klein Pascal , Wilhelm Thomas , Kuhn Jochen
Published: September 2021

Zu den Sensoren an Bord heutiger Smartphones gehören auch integrierte Barometer. Clever eingesetzt, kann man mit diesen Luftdrucksensoren das Smartphone zur Waage machen.
Investigation of Bioimpacts of Metallic and Metallic Oxide Nanostructured Materials: Size, Shape, Chemical Composition, and Surface Functionality: A Review
Authors: Fatehbasharzad Parisa , Fatehbasharzad Pegah , Sillanpää Mika , Shamsi Zahra
Published: September 2021

Nanotechnology is set to impact a wide range of various fields, including medicine, materials technology, environmental sciences, and engineering/manufacturing. Nanoparticles are categorized depending on their size, composition, shape, and surface functionality. Due to the excessive growth of nanostructured materials (NSMs) in production and industrial applications, human and environmental exposure to them and their possible toxicity issues are inevitable. The main objective of this review is to study NSMs, in particular metallic and metallic oxide nanoparticles, and properties that have a determinative role in their bioimpacts. Nevertheless, the main focus is to provide an overview of NSMs toxicology. Medical and environmental applications of the NSMs are discussed here. Also, key factors on the toxicity of the nanoparticles such as shape, size, chemical composition, and surface functionality are discussed. Finally, toxicity of the nanoparticles is going to be highlighted, and relevant studies are critically compared. This review gives a broad scientific view for improving the functional efficiency of nanomaterials while mitigating their possible adverse and unintended effects on biological systems.
Outcomes of infants born during the first 9 years of CF newborn screening in the United States: A retrospective Cystic Fibrosis Foundation Patient Registry cohort study
Authors: Martiniano Stacey L. , Elbert Alexander A. , Farrell Philip M. , Ren Clement L. , Sontag Marci K. , Wu Runyu , McColley Susanna A.
Published: September 2021

Introduction

Newborn screening (NBS) for cystic fibrosis (CF) was implemented in all US states and DC by 2010. This hypothesis‐generating study was designed to form the basis of additional analyses and to plan quality improvement initiatives. The aims were to describe the outcomes of infants with CF born during the first 9 years of universal NBS.

Methods

We included participants in the CF Foundation Patient Registry born 2010–2018 with age of recorded CF diagnosis 0–365 days old. We compared the age of center‐reported diagnosis, age at first CF event (defined as earliest sweat test, clinic visit, or hospitalization), demographics, and outcomes between three cohorts born between 2010–2012, 2013–2015, and 2016–2018.

Results

In 6354 infants, the median age at first CF event decreased from the first to the third cohort. Weight‐for‐age (WFA) was < 10th percentile in about 40% of infants at the first CF Center visit. Median WFA z‐score at 1–2 years was more than 0 but height‐for‐age (HFA) z‐score was less than 0 through age 5–6 years. The second cohort had a higher HFA z‐score than the first cohort at age 5–6 years. Pseudomonas aeruginosa infection was less common in later cohorts. About 1/3 of infants were hospitalized in the first year of life with no changes over time.

Conclusion

Over 9 years of CF NBS, median age at first CF event decreased. CF NBS had positive health impacts, but early life nutritional deficits and a high rate of infant hospitalizations persist.
Susceptibility of Demotispa neivai (Coleoptera: Chrysomelidae) to Beauveria bassiana and Metarhizium anisopliae entomopathogenic fungal isolates
Authors: Martínez Luis Carlos , Plata‐Rueda Angelica , Ramírez Augusto , Serrão José Eduardo
Published: August 2021

BACKGROUND

The potential of Beauveria bassiana and Metarhizium anisopliae isolates obtained from naturally infected oil palm pests was evaluated to control Demotispa neivai as an alternative for organophosphate insecticide use in oil palm crops in Latin America. Two B. bassiana (Bb‐0018 and Bb‐0025) and two M. anisopliae (Ma‐0002 and Ma‐0003) isolates were tested against D. neivai adults for hydrophobicity, virulence, survival, adhesion to host cuticle, and mortality in semi‐field conditions.

RESULTS

Concentration–mortality bioassays demonstrate that isolates had lethal effect on D. neivai adults with Bb‐0025 [median lethal concentration (LC50) = 3.45 × 107 conidia mL−1] and Bb‐0018 (LC50 = 3.75 × 107 conidia mL−1) being the most effective followed by Ma‐0003 (LC50 = 3.38 × 108 conidia mL−1) and Ma‐0002 (5.33 × 108 conidia mL−1). Adult survival was 99% without exposure to fungal isolates, decreasing to 21.65% in insects exposed to Ma‐0002, 19.41% with Ma‐0003, 20.13% with Bb‐0018, and 0.17% with Bb‐0025. Mortality of D. neivai adults caused by the entomopathogenic fungal isolates was similar in both laboratory and semi‐field conditions. Also, vegetative growth of the entomopathogenic fungal isolates was found in infected D. neivai adults in the field.

CONCLUSION

Our data suggest that the tested entomopathogenic fungal isolates are effective against D. neivai with potential to be used as biological control agents contributing to the decrease of the use of chemical insecticides to control this oil palm pest. © 2021 Society of Chemical Industry.
Comparison of different strategies towards the chemical synthesis of long‐chain scorpion toxin AaH‐II
Authors: Li Yu‐Lei , Qu Qian , Qi Yun‐Kun , Liu Lei , Wang Ke Wei , Liu Yani , Fang Ge‐Min
Published: September 2021

Long‐chain scorpion toxin AaH‐II isolated from Androctonus australis Hector can selectively inhibit mammalian voltage‐gated sodium ion channel Nav1.7 responsible for pain sensation. Efficient chemical synthesis of AaH‐II and its derivatives is beneficial to the study of the function and mechanism of Nav1.7 and the development of potential peptide inhibitors. Herein, we compared three different strategies, namely, direct solid‐phase peptide synthesis, hydrazide‐based two‐segment native chemical ligation, and hydrazide‐based three‐segment native chemical ligation for the synthesis of AaH‐II. The hydrazide‐based two‐segment native chemical ligation affords the target toxin with the optimal efficiency, which provides a practically robust procedure for the preparation of tool molecules derived from AaH‐II to study the biological functions and modulation of Nav1.7. Our work highlights the importance of selecting suitable segment condensation approach in the chemical synthesis of protein toxins.
Attitudes towards rural migrants and their influence on return migration in China
Authors: Zhou Jing , Tang Shuangshuang
Published: August 2021

Compared with the enormous attention paid to the formation of attitudes towards migrants, studies on the social consequences of such attitudes have been insufficient, with the link between attitudes towards migrants and return migration remaining an understudied field both in global and Chinese contexts. Contextual hostility creates social and symbolic barriers in the integration process of migrants and decreases their life satisfaction levels and thus significantly influences many types of migration trajectories. Based on the only available national data for China, this study applies multilevel logistic regression models to examine the relationship betweenlocal‐hukouresidents' attitudes towards migrants and the intention for return migration among rural‐to‐urban migrants while accounting for socio‐economic heterogeneity in migrants. Results reveal that, for all types oflocal‐hukouresidents, their acceptance of migrants as either friends, neighbours, or family members positively relates to the intention for return migration among rural‐to‐urban migrants; by contrast, it is only hostility from native‐bornlocal‐hukouresidents that has a significant and negative effect on rural‐to‐urban migrants, encouraging them to plan to return to their places of origin. Moreover, migrants with different amounts of human capital have varied perceptions of attitudes held bylocal‐hukouresidents, with the younger generation of migrants, highly educated migrants, and business migrants being more sensitive to contextual hostility. Thus, they exhibit a greater tendency towards return migration. This study broadens the understanding of return migration from the perspectives of life satisfaction and psychological integration and suggests creating a more open and friendlier social environment in cities.
Electrical and Structural Characterization of Polyaniline Synthesized in Acid Medium Having Nickel Salts as Impurities
Authors: Huanca Danilo Roque
Published: September 2021

Electrical properties of polyaniline (PANI) synthesized in a solution containing nickel salts are investigated. The structural characterization by scanning electron microscopy shows that PANI yielded in nickel chloride (NiCl2) has thicker structures with high porosity that increases insofar NiCl2concentration does. The pH variation monitoring due to the nickel salt inclusion in solution shows that mass and thickness are strongly dependent on pH variation. Thermogravimetric investigation reveals that PANI formed in the presence of nickel salts is thermally more stable. This fact is more accentuated in samples produced in nickel nitrate and, also, produces the absorbance peak shift of some functional groups, as well as their intensification, as pointed by the infrared spectroscopy analysis. On the other side, the electrical characterization through the current–potential analysis shows that PANI conductivity is larger in PANI yielded in the presence of sulfates and lower in nitrates, while the impedance electrochemical analysis evidences the formation of a surface passivated PANI region having higher resistance and lower capacitance than PANI in bulk. Concerning the resistance of this region, the difference between surface and bulk PANI is smaller in the sample yielded in NiCl2, but the difference in capacitance is greater.
The Degradation Mechanism of Mg2Si during Exploitation at High Temperature
Authors: Liao Yangfang , Xie Jing , Lv Bing , Wu Dongni , Xiao Qingquan , Xie Quan
Published: August 2021

Oxidized Mg2Si films are annealed in low vacuum at various annealing temperature, and the degradation mechanism of Mg2Si during exploitation at high temperature is investigated. The crystal structure, surface morphology, depth profile, Raman scattering, and electrical properties are measured by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X‐ray photoelectron spectroscopy (XPS), Raman spectroscopy, and Hall effect system, respectively. XRD results show that MgO exists apparently in Mg2Si films, and as the annealing temperature increases, the content of MgO increases. The surfaces of films present distinct hexagon structures. The results of depth profiles show that the oxygen content decreases gradually from the surface to the subsurface. Raman spectroscopy analysis suggests that as the annealing temperature increases, the intensity of MgO peak enhances gradually. Hall measurement results indicate that the carrier concentration and mobility decrease significantly with the increase in annealing temperature. The films show n‐type at lower annealing temperature, while they present p‐type at higher annealing temperature, which indicates obvious conversions from n‐ to p‐type.
Latent space data assimilation by using deep learning
Authors: Peyron Mathis , Fillion Anthony , Gürol Selime , Marchais Victor , Gratton Serge , Boudier Pierre , Goret Gael
Published: September 2021

Performing data assimilation (DA) at low cost is of prime concern in Earth system modeling, particularly in the era of Big Data, where huge quantities of observations are available. Capitalizing on the ability of neural network techniques to approximate the solution of partial differential equations (PDEs), we incorporate deep learning (DL) methods into a DA framework. More precisely, we exploit the latent structure provided by autoencoders (AEs) to design an ensemble transform Kalman filter with model error (ETKF‐Q) in the latent space. Model dynamics are also propagated within the latent space via a surrogate neural network. This novel ETKF‐Q‐Latent (ETKF‐Q‐L) algorithm is tested on a tailored instructional version of Lorenz 96 equations, named the augmented Lorenz 96 system, which possesses a latent structure that accurately represents the observed dynamics. Numerical experiments based on this particular system evidence that the ETKF‐Q‐L approach both reduces the computational cost and provides better accuracy than state‐of‐the‐art algorithms such as the ETKF‐Q.
PISA 2018 in England, Northern Ireland, Scotland and Wales: Is the data really representative of all four corners of the UK?
Authors: Jerrim John
Published: August 2021

PISA is an influential international study of the achievement of 15‐year‐olds. It has a high profile across the devolved nations of the UK, with the results having a substantial impact upon education policy. Yet many of the technical details underpinning PISA remain poorly understood—particularly amongst non‐specialists—including important nuances surrounding the representivity of the data. This paper provides new evidence on this issue, based upon a case study of PISA 2018. I illustrate how there are many anomalies with the data, with the combination of nonresponse, exclusions from the test and technical details surrounding eligibility criteria leading to total nonparticipation rates of around 40% (amongst the highest anywhere in the world). It is then shown how this leads to substantial uncertainty surrounding the PISA results, with clear evidence of bias in the sample for certain parts of the UK. I conclude by discussing how more transparent reporting of the technical details underpinning PISA is needed, at both a national and international level.
Density Functional Theory Study of Ultrashort Metal−Metal Distances in Diberyllium Complexes Bearing Carbene Ligands
Authors: Sun Lili
Published: September 2021

Diberyllium complexes with ultrashort metal−metal distances (USMMDs, defined asdM−M<1.900 Å) are fascinating for the nature of the valence electronic structure of Be atoms. In this paper a family of diberyllium complexes [L−BeH3Be−L]+(1–7), in which L was anN‐heterocyclic carbene (NHC) or a mesoionic carbene (MIC), were studied by Density Functional Theory (DFT) at the B3LYP/cc‐pVTZ level. It was found that complexes1–7possessed ultrashort Be−Be distances of 1.754 Å–1.779 Å and strong covalent bonds between a Be atom and its adjacent carbene center (Ccarb) at once. Electronic structures and chemical bonding analyses ascribed USMMDs between the Be atoms to the Be−H−Be three‐center two‐electron (3c‐2e) bonds. The strong Be−Ccarbbonds were determined by combining effects of covalent interaction and electrostatic interaction between the Be and the Ccarbatoms. These complexes exhibited a great stability with large highest occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) gaps, high vertical detachment energies (VDEs) and low vertical electron affinities (VEAs) and are potential targets in future experiments.
Practical Synthesis for N‐doped Carbon Microsphere Coated with Zn0.76Co0.24S Nanoparticles towards High‐performance Supercapacitors
Authors: Zhang Wenjun , Zhou Ting , Hao Yonghao , Wang Zhongbing , Chen Chunnian
Published: September 2021

To meet the market demand for supercapacitors with large capacitance and high stability, we successfully prepared a new type of composit material of N−C@Zn0.76Co0.24S with a hierarchical structure utilizing solvothermal and calcination. The nanostructures and electrochemical properties of the samples were tested and analyzed. By adjusting the mass ratio of the N‐doped carbon microsphere during the process of synthesizing composite materials, a series of comparative materials were obtained. The result of research shows that, when the mass ratio of the N‐doped carbon microsphere in the composite was 55 %, the nanocomposite demonstrated excellent specific capacitance (2033.7 F g−1 at a current density of 1 A g−1) and strong cycle performance (retain 88.4 % after 5000 charge‐discharge cycles), far superior to that of the single metal sulfide coating on N‐doped carbon microsphere. When assembled into N−C@ZCS//AC asymmetric supercapacitor (ASC), the ASC exhibits a large energy density of 79.6 Wh kg−1 while the power density is 799.7 W kg−1, proving the composite materials have positive significance in the application of supercapacitors.
Oxygen Enriched Oxamides and N‐Dinitrated Oxamides: Trinitroethyl Esters, Nitrocarbamates and Nitrates
Authors: Klapötke Thomas M. , Krumm Burkhard , Reith Thomas , Riedelsheimer Christian
Published: September 2021

Starting from the readily available starting materials diethyl oxalate, glycine and β‐alanine, some new N‐nitrated oxamides were synthesized. Oxamides formed by condensation reactions were subsequently nitrated to form the corresponding dinitroxamides. These were further converted to the corresponding acid chlorides with the utilization of thionyl chloride. The final reaction of the β‐alanine based dinitroxamide with trinitroethanol generated the energetic target ester in moderate yield and high purity. Additionally, starting from diethyl oxalate and ethanolamine gave access to a nitrocarbamate based on an oxamide. Furthermore, the previously reported compound bis(2‐nitratoethyl) oxamide was synthesized now in a more facile fashion and fully characterized, especially in case of the energetic properties, sensitivities and crystal structure. The compounds were fully analysed by NMR spectroscopy, vibrational analysis and elemental analysis. The heat of formation was calculated with the Gaussian program package and in combination with the experimental density the energetic properties were estimated utilizing the Explo5 computer code.