bluuebunny/crossref_metadata_2025 huggingface dataset:
High‐resolution continuous‐wave coherent anti‐Stokes Raman spectroscopy in a CO2‐filled hollow‐core photonic crystal fiber
Authors: Xiong Dongsheng , Bai Yusi , Zuo Duluo , Wang Xinbing
Published: February 2021

We demonstrated high‐resolution continuous‐wave (CW) coherent anti‐Stokes Raman spectroscopy of gaseous samples in a single ring hollow‐core photonic crystal fiber. Pump beam and Stokes beam were provided by CW single longitudinal mode lasers. These narrow linewidth lasers brought the benefit of a spectral resolution of 99 MHz. The high resolution allowed a measurement of a linewidth 0.3 GHz of the ν1 transition of CO2 in a gas mixture with partial pressure of 0.15 MPa and total pressure of 0.9 MPa. Pump beam from a tunable dye laser and Stokes beam from an external cavity diode laser were coupled into the fiber containing gaseous CO2. Fundamental mode phase matching was achieved by tuning gas pressure. The long interaction length provided by the hollow fiber yielded a 60‐dB increase in the anti‐Stoke signal. The attained signal to noise ratio of the spectrum of ν1 component of 0.6‐MPa CO2 was ~25,000 with 152‐mW pump power and 1.4‐mW Stokes power.
Lily bulbs’ polyphenols extract ameliorates oxidative stress and lipid accumulation in vitro and in vivo
Authors: Kan Juan , Hui Yaoyao , Xie Wangjing , Chen Cuicui , Liu Ying , Jin ChangHai
Published: February 2021

BACKGROUND

Polyphenols have the potential to reduce the risk of many metabolic disorders. Lily bulbs are rich in polyphenols; however, their effects on lipid metabolism remain unclear. This study aimed to explore the effects of lily bulbs’ polyphenols (LBPs) on oxidative stress and lipid metabolism.

RESULTS

A total of 14 polyphenolic compounds in LBPs were identified by high‐performance liquid chromatography equipped with diode‐array detection mass spectrometry. Total phenolic compound in LBPs was 53.76 ± 1.12 g kg−1 dry weight. In cellular experiments, LBPs attenuated the disruption of mitochondrial membrane potential, impeded reactive oxygen species production, alleviated oxidative stress, and reduced lipid accumulation in oleic acid induced HepG2 cells. In in vivo studies, LBPs significantly inhibited body weight gain, reduced lipid levels in serum and liver, and improved oxidative damage in a dose‐dependent manner in mice fed a high‐fat diet. Moreover, LBPs ameliorated hepatic steatosis and suppressed the expression of hepatic‐lipogenesis‐related genes (SREBP‐1c, FAS, ACC1, and SCD‐1) and promoted lipolysis genes (SRB1 and HL) and lipid oxidation genes (PPARα and CPT‐1) in mice fed a high‐fat diet.

CONCLUSION

It was concluded that LBPs are a potential complementary therapeutic alternative in the development of functional foods to curb obesity and obesity‐related diseases, such as metabolic syndrome. © 2021 Society of Chemical Industry
Evaluating the feasibility of performing elective gastrointestinal cancer surgery during the COVID‐19 pandemic: An observational study with 60 days follow‐up results of a tertiary referral pandemic hospital
Authors: Sozutek Alper , Seker Ahmet , Kuvvetli Adnan , Ozer Nazmi , Genc Ismail Caner
Published: February 2021

Background

The coronavirus disease 2019 (COVID‐19) pandemic has interfered with the treatment algorithm for patients with gastrointestinal (GIS) cancer, resulting in deferral of surgery. We presented the outcomes of our patients to evaluate whether surgery could be safely performed and followed‐up without delaying any stage of GIS cancer during the pandemic.

Methods

This was an observational study of 177 consecutive patients who underwent elective GIS cancer surgery between March 11 and November 1, 2020. They were assessed regarding their perioperative and 60 days follow‐up results for either surgical or COVID‐19 status. Morbidity was determined according to the Clavien‐Dindo classification (CDC). Continuous and categorical data were presented as median ± SD and number with percentage (%), respectively.

Results

The study included 44 gastric, 33 pancreatic, 40 colon, and 59 rectal cancer patients. All patients underwent surgery and received neo/adjuvant treatments without delay. The overall morbidity (CDC grade II–IV) and mortality rates were 10.1% and 3.9%, respectively. None of the patients or medical staff were infected with COVID‐19 during the study period.

Conclusion

GIS cancer surgery can be safely performed even within a pandemic hospital if proper isolation measures can be achieved for both patients and health workers. Regardless of the tumor stage, surgery should not be deferred, depending on unstandardized algorithms.
Dissipation of tiafenacil in five types of citrus orchard soils using the HPLC‐MS coupled with the quick, easy, cheap, effective, rugged, and safe method
Authors: Gao Meizhu , Bian Chuanfei , Zhou Wenwen , Liu Lang , Li Baotong , Tang Limei
Published: February 2021

Tiafenacil is a new contact herbicide and its environmental behavior after field application remains poorly understood. In order to understand the dissipation of tiafenacil in the soil, the tiafenacil dissipation experiment was conducted at citrus orchard sites in five provinces of China (Gansu, Shandong, Sichuan, Jiangxi, and Hainan) in 2019 and 2020 (July–August) and the relevant determination methods were optimized. The results showed that the established method showed good linearity in the concentration range of 0.01–0.5 mg/kg. The average recoveries of tiafenacil from the five soils were 86.31–101.66%, with coefficients of variation of 0.28–10.79%. The dissipation of tiafenacil at the five experimental sites conformed to the first‐order kinetic equation, Ct = C0 exp−kt (R2 = 0.8130 – 0.9967). The half‐life of tiafenacil ranged from 0.26 to 4.19 days. The dissipation rate of tiafenacil was positively correlated with soil organic matter content and negatively correlated with soil pH, while monthly average temperature and total rainfall were less influential than soil properties. Therefore, the established method was simple and effective for tiafenacil residue analysis in citrus orchard soils. Tiafenacil could readily dissipate in soil and might be a safe alternative to glyphosate for weed control in citrus orchards.
Comparing Long‐Term Outcomes in Tracheostomy Placed in the First Year of Life
Authors: Salley Jordan R. , Kou Yann‐Fuu , Shah Gopi B. , Johnson Romaine F.
Published: February 2021

Objectives//Hypothesis

To characterize long‐term outcomes in pediatric patients requiring tracheotomy in the first year of life.

Study Design

Retrospective case series.

Methods

A retrospective longitudinal registry of tracheostomy patients was queried for patients who underwent tracheotomy from birth to 11 months. Primary outcomes were decannulation and survival. Secondary outcomes included neurocognitive quality of life assessed with the PedsQL Family Impact Module (scored from worst to best, 0 to 100 points).

Results

The study included 337 children. Thirty (8.90%) were neonates and 307 (91.10%) were infants. The population was 56.08% male (n = 189), and the racial and ethnicity composition were equally distributed (29.97% White, 31.45% Black, and 31.16% Hispanic). Significant differences between neonates and postneonates included birth weight in grams (2,731.40 vs. 1,950.44, P < .05), extreme prematurity (13.33% vs. 38.88%, P = .01), upper airway obstruction (80.00% vs. 42.67%, P < .05), and the need for mechanical ventilation (40.00% vs. 83.71%, P < .05). Despite these differences, long‐term outcomes were similar: decannulation (X2 = 2.19, P = .14), death (X2 = 2.63, P = .11), and neurocognitive quality of life (X2 = 2.63, P = .27). Having a child with a tracheostomy caused the most problems with being physically tired (mean = 75.32 ± 3.90), emotional frustration (mean = 77.31 ± 5.05), and worry (mean standard deviation = 74.23 ± 6.48).

Conclusion

There were demographic differences between neonatal and infantile tracheostomy patients, but they did not affect long‐term outcomes. The presence of a tracheostomy caused a significant impact on a family's quality of life.

Level of Evidence

3 Laryngoscope, 131:2115–2120, 2021
Quantitative clinical glycomics strategies: A guide for selecting the best analysis approach
Authors: Patabandige Milani W. , Pfeifer Leah D. , Nguyen Hanna T. , Desaire Heather
Published: February 2021

Glycans introduce complexity to the proteins to which they are attached. These modifications vary during the progression of many diseases; thus, they serve as potential biomarkers for disease diagnosis and prognosis. The immense structural diversity of glycans makes glycosylation analysis and quantitation difficult. Fortunately, recent advances in analytical techniques provide the opportunity to quantify even low‐abundant glycopeptides and glycans derived from complex biological mixtures, allowing for the identification of glycosylation differences between healthy samples and those derived from disease states. Understanding the strengths and weaknesses of different quantitative glycomics analysis methods is important for selecting the best strategy to analyze glycosylation changes in any given set of clinical samples. To provide guidance towards selecting the proper approach, we discuss four widely used quantitative glycomics analysis platforms, including fluorescence‐based analysis of released N‐linked glycans and three different varieties of MS‐based analysis: liquid chromatography (LC)‐mass spectrometry (MS) analysis of glycopeptides, matrix‐assisted laser desorption ionization‐time of flight MS, and LC‐ESI‐MS analysis of released N‐linked glycans. These methods' strengths and weaknesses are compared, particularly associated with the figures of merit that are important for clinical biomarker studies, including: the initial sample requirements, the methods' throughput, sample preparation time, the number of species identified, the methods' utility for isomer separation and structural characterization, method‐related challenges associated with quantitation, repeatability, the expertise required, and the cost for each analysis. This review, therefore, provides unique guidance to researchers who endeavor to undertake a clinical glycomics analysis by offering insights on the available analysis technologies.
Challenges in Clinicogenetic Correlations: One Phenotype – Many Genes
Authors: Gannamani Rahul , van der Veen Sterre , van Egmond Martje , de Koning Tom J. , Tijssen Marina A.J.
Published: February 2021

Background

In the field of movement disorders, what you see (phenotype) is seldom what you get (genotype). Whereas 1 phenotype was previously associated to 1 gene, the advent of next‐generation sequencing (NGS) has facilitated an exponential increase in disease‐causing genes and genotype–phenotype correlations, and the “one‐phenotype‐many‐genes” paradigm has become prominent.

Objectives

To highlight the “one‐phenotype‐many‐genes” paradigm by discussing the main challenges, perspectives on how to address them, and future directions.

Methods

We performed a scoping review of the various aspects involved in identifying the underlying molecular cause of a movement disorder phenotype.

Results

The notable challenges are (1) the lack of gold standards, overlap in clinical spectrum of different movement disorders, and variability in the interpretation of classification systems; (2) selecting which patients benefit from genetic tests and the choice of genetic testing; (3) problems in the variant interpretation guidelines; (4) the filtering of variants associated with disease; and (5) the lack of standardized, complete, and up‐to‐date gene lists. Perspectives to address these include (1) deep phenotyping and genotype–phenotype integration, (2) adherence to phenotype‐specific diagnostic algorithms, (3) implementation of current and complementary bioinformatic tools, (4) a clinical‐molecular diagnosis through close collaboration between clinicians and genetic laboratories, and (5) ongoing curation of gene lists and periodic reanalysis of genetic sequencing data.

Conclusions

Despite the rapidly emerging possibilities of NGS, there are still many steps to take to improve the genetic diagnostic yield. Future directions, including post‐NGS phenotyping and cohort analyses enriched by genotype–phenotype integration and gene networks, ought to be pursued to accelerate identification of disease‐causing genes and further improve our understanding of disease biology.
A class of fractal Hilbert‐type inequalities obtained via Cantor‐type spherical coordinates
Authors: Baleanu Dumitru , Krnić Mario , Vukovic Predrag
Published: February 2021

We present a class of higher dimensional Hilbert‐type inequalities on a fractal set
. The crucial step in establishing our results are higher dimensional spherical coordinates on a fractal space. Further, we impose the corresponding conditions under which the constants appearing in the established Hilbert‐type inequalities are the best possible. As an application, our results are compared with the previous results known from the literature.
Repeatability of multinuclear interleaved acquisitions with nuclear Overhauser enhancement effect in dynamic experiments in the calf muscle at 3T
Authors: Lopez Kolkovsky Alfredo L. , Marty Benjamin , Giacomini Eric , Meyerspeer Martin , Carlier Pierre G.
Published: February 2021

Purpose

To evaluate the repeatability of multinuclear interleaved 1H/31P NMR dynamic acquisitions in skeletal muscle and the impact of nuclear Overhauser enhancement (nOe) on the 31P results at 3T in exercise‐recovery and ischemia‐hyperemia paradigms.

Methods

A 1H/31P interleaved pulse sequence was used to measure every 2.5 s a perfusion‐weighted image, a map, a 31P spectrum and 32 1H spectra sensitive to deoxymyoglobin. 21 subjects performed a plantar flexion exercise and after recovery underwent an 8‐min lower leg ischemia. The procedure was repeated in visit 2 with 12 subjects. An additional exercise bout without 1H excitation was appended to visit 1. Individual 1H RF pulse nOe was measured at rest in every visit.

Results

Repeatability scores (coefficient of variation, Bland‐Altman analysis) were similar to those found in the literature using similar mono‐nuclear acquisitions. |Pi]/[PCr], pH drop, creatine rephosphorylation rate (τPCr), maximum perfusion, time to peak perfusion, and blood flow post‐exercise showed high reliability (intraclass correlation coefficient > 0.7), whereas hemodynamic results from reactive hyperemia showed higher repeatability. After accounting for nOe, which increased Pi and PCr signal‐to‐noise ratio by 30%, no differences in 31P results were observed between interleaved and 31P MRS‐only acquisitions. τPCr was unaffected by nOe.

Conclusion

The method shows good repeatability for both paradigms while simultaneously providing multiple dynamic data sets on a clinical scanner. The nOe effects were accounted for on a per‐subject and per‐visit basis using a short 31P reference scan. This multiparametric approach has a multitude of applications for the study of oxygen utilization and ATP turnover in the muscle.
No need to detune transmitters in 32‐channel receiver arrays at 7 T
Authors: Gosselink Mark , Hoogduin Hans , Froeling Martijn , Klomp Dennis W. J.
Published: February 2021

Ultrahigh field magnetic resonance imaging facilitates high spatiotemporal resolution that benefits from increasing the number of receiver elements. Because high‐density receiver arrays have a relatively small element size compared with the transmitter, a side effect is that such setups cause low flux coupling between the transmitter and receiver. Moreover, when transmitters are designed in a multitransmit configuration, their relative size is much smaller than the sample, reducing coupling to the sample and thereby potentially also the coupling to the receivers. Transmitters are traditionally detuned during reception. In this study, we investigate, for a 32‐channel receiver head array at 7 T, if transmitter detuning of a quadrature birdcage or of an eight‐channel transmit coil can be omitted without substantially sacrificing signal‐to‐noise ratio (SNR). The transmit elements are operated once with and once without detuning and, in the latter, the received signals are either merged with the array or excluded for image reconstruction. For each of the three measurements, SNR and 1/g‐factor maps are investigated. The tuning of the quadrature and eight‐channel transmit coils during signal reception introduced a 10.1% and 6.5% penalty in SNR, respectively, relative to the SNR received with detuned transmitters. When also incorporating the signal of the transmit coils, the SNR was regained to 98.5% or 101.4% for the quadrature and eight‐channel coil, respectively, relative to the detuned transmitters, while the 1/g‐factor maps improved slightly. For the 32‐channel receive coil used the SNR penalty can become negligible when omitting detuning of the transmit coils. This not only simplifies transmit coil designs, potentially increasing their efficiency, but also enables the transmitters to be used as receivers in parallel to the receiver array, thus increasing parallel imaging performance.
Effects of Ado-Trastuzumab Emtansine and Fam-Trastuzumab Deruxtecan on Metastatic Breast Cancer Harboring HER2 Amplification and the L755S Mutation
Authors: Mukohara Toru , Hosono Ako , Mimaki Sachiyo , Nakayama Akiko , Kusuhara Shota , Funasaka Chikako , Nakao Takehiro , Fukasawa Yoko , Kondoh Chihiro , Harano Kenichi , Naito Yoichi , Matsubara Nobuaki , Tsuchihara Katsuya , Kuwata Takeshi
Published: February 2021

Somatic mutations in human epidermal growth factor receptor 2 (HER2) are present in approximately 3% of breast cancers. Some HER2 mutations are activating, and they represent a mechanism of resistance to conventional anti-HER2 therapies such as trastuzumab and lapatinib. Consistently, in patients with HER2-amplified breast cancer, these mutations are predominantly observed in metastatic tumors obtained after exposure to anti-HER2 systemic therapies, possibly after clonal selection. Therefore, it is rare to find coexistent HER2 mutation and amplification in the early clinical course, and thus, the clinical relevance of HER2 mutation to the sensitivity to HER2-targeted drugs, particularly antibody-drug conjugates (ADCs) such as ado-trastuzumab emtansine (T-DM1) and the recently approved fam-trastuzumab deruxtecan (T-DXd), remains unclear. In this article, we describe a patient with de novo metastatic breast cancer who exhibited both HER2 amplification and the L755S mutation in the untreated primary breast tumor obtained at the initial diagnosis, and the lesion responded to T-DM1 and T-DXd after exhibiting clinical resistance to other HER2-targeted drugs. Our current case findings suggested that anti-HER2 ADCs should be prioritized over conventional trastuzumab- or lapatinib-based therapies for patients with HER2-amplified and comutated tumors.

Key Points

Although HER2 mutations were implicated in resistance to anti-HER2 monoclonal antibodies or HER2 tyrosine kinase inhibitors in preclinical studies, their clinical impact on sensitivity to anti-HER2 drugs is unclear owing to the rarity of concomitant HER2 mutation and HER2 amplification. A case of de novo metastatic breast cancer harboring both HER2 amplification and the L755S mutation in an untreated breast primary tumor displayed clinical resistance to standard trastuzumab- or lapatinib-based therapies but good responses to ado-trastuzumab emtansine (T-DM1) and fam-trastuzumab deruxtecan (T-DXd). Anti-HER2 antibody-drug conjugates such as T-DM1 and T-DXd may be prioritized over conventional trastuzumab- or lapatinib-containing therapies for patients with HER2-amplified and comutated tumors.
Chalcogenido‐Dimethylgallates and ‐Indates DMPyr2[Me2M(μ2−E)]2 (M=Ga, In; E=S, Se): Building Blocks for Higher and Lower Order Chalcogenidoindates
Authors: Guschlbauer Jannick , Vollgraff Tobias , Finger Lars H. , Harms Klaus , Sundermeyer Jörg
Published: February 2021

Metalation of the anions in the ionic liquids DMPyr[SH] and DMPyr[SeH] (DMPyr=1,1‐dimethylpyrrolidinium) by trimethylgallium and trimethylindium is investigated. The reaction proceeds via pre‐coordination of [EH]−, methane elimination and formation of an unprecedented series of chalcogenido metalates DMPyr2[Me2M(μ2−E)]2 (M=Ga, In; E=S, Se). These show the presences of dinuclear dianions with four‐membered ring structures displaying highly nucleophilic bridging chalcogenide ligands in their crystallographically determined molecular structures. Some representative reactions of these building blocks with amphoteric electrophiles were studied: Addition of two equivalents of E(SiMe3)2 (E=S, Se) to the indates DMPyr2[Me2In(μ2−S)]2 and DMPyr2[Me2In(μ2−Se)]2 leads to a cleavage of the ring, E silylation and formation of mononuclear, monoanionic indates DMPyr[Me2In(SSiMe3)2], DMPyr[Me2In(SeSiMe3)2], and even a mixed sulfido‐selenido dimethylindate DMPyr[Me2In(SSiMe3)(SeSiMe3)]. Reaction of DMPyr2[Me2In(μ2−S)]2 with two equivalents of Lewis acid Me3In leads to charge delocalization, ring expansion and formation of six‐membered ring DMPyr3[Me2In(μ2−S−InMe3)]3. The latter is a key intermediate in the formation of dianionic sulfidoindate DMPyr2[(Me2In)6(μ3−S)4] displaying an unusual inverse heteroadamantane cage structure with four capping sulfido ligands.
High‐skilled emigration and child health in Africa
Authors: Immurana Mustapha
Published: February 2021

Africa is estimated to lose a very significant number of high‐skilled individuals through emigration. This has resulted in a number of studies investigating the effect of high‐skilled emigration on socio‐economic indicators in Africa. Notwithstanding, the majority of these studies have examined the effect of high‐skilled emigration on economic growth, with less attention paid to health outcomes. Meanwhile, health outcomes, especially child health outcomes, have major implications for future human capital and overall economic development. With sub‐Saharan Africa (SSA) having the highest child mortality rate in the world, this study, therefore, investigates the effect of the emigration of high‐skilled individuals on child health in 48 African countries for the period, 1985–2010. Neonatal mortality and infant mortality rates are used to proxy child health. The panel fixed effects and the dynamic panel system Generalised Methods of Moments (GMM) regressions are employed as estimation techniques. Using the panel fixed effects, we find that, while the emigration of high‐skilled individuals is detrimental to neonatal mortality, in the case of infant mortality, it is insignificant. However, after controlling for endogeneity using the dynamic panel system GMM, the emigration of high‐skilled individuals is found to be detrimental to both neonatal mortality and infant mortality. The results suggest that, in order to enhance child mortality in Africa, attention should be paid towards decreasing high‐skilled emigration on the continent.
The impact of trade openness on urbanization: Empirical evidence from BRICS economies
Authors: Chhabra Megha , Giri Arun Kumar , Kumar Arya
Published: February 2021

The present study investigates the impact of trade openness on urbanization in BRICS countries, covering data from 1991 to 2017. The study uses instrument variable approach and two‐system least square method for the empirical analysis. Based on the empirical results, the study confirms the positive and significant link between trade openness and urbanization as per the New Growth Theory. The results show that the cities having more access to global trade links tend to be highly urbanized. The findings also suggest that the increasing urban concentration affects the export and import positively and enhances trade openness. However, the urban population concentration turns out to be affected negatively by trade openness in the centrally located regions. The agriculture commodity trade is found to be positively affected by the increased openness and GDP of BRICS economies. Finally, the findings suggested that trade openness plays a substantial role in promoting urban concentration in these five emerging market economies.
Outcomes after first relapse of childhood intracranial ependymoma
Authors: Tsai Jessica W. , Manoharan Neevika , Alexandrescu Sanda , Zimmerman Mary Ann , Scully Jacqueline , Chordas Christine , Clymer Jessica , Wright Karen D. , Filbin Mariella , Ullrich Nicole J. , Marcus Karen J. , Haas‐Kogan Daphne , Chi Susan N. , Bandopadhayay Pratiti , Yeo Kee Kiat
Published: February 2021

Background

Ependymoma is the third most common malignant CNS tumor in children. Despite multimodal therapy, prognosis of relapsed ependymoma remains poor. Approaches to therapy for relapsed ependymoma are varied. We present a single‐institution retrospective review of the outcomes after first relapse of intracranial ependymoma in children.

Procedure

We performed a retrospective, IRB‐approved chart review of patients with recurrent intracranial ependymoma treated at Dana‐Farber/Boston Children's Cancer and Blood Disorders Center from 1990 to 2019.

Results

Thirty‐four patients with relapsed intracranial ependymoma were identified. At initial diagnosis, 11 patients had supratentorial disease, 22 with posterior fossa disease and one with metastatic disease. Median time‐to‐first relapse was 14.9 months from initial diagnosis (range 1.4–52.5). Seven patients had metastatic disease at first relapse. Gross total resection (GTR) was associated with improved 5‐year progression‐free survival (PFS) relative to subtotal resection (STR) and no surgery (p = .005). Localized disease at relapse was associated with improved 5‐year overall survival (OS) when compared to metastatic disease (p = .02). Irradiation at first relapse seemed to delay progression but was not associated with statistically prolonged PFS or OS. Tumor location, histology, and chromosomal 1q status did not impact outcome at first relapse, although available molecular data were limited making definitive conclusions difficult. Median time‐to‐second relapse was 10 months (range 0.7–124). Five‐year PFS and OS after first relapse were 19.9% and 45.1%, respectively. Median PFS and OS were 10.0 and 52.5 months after first relapse, respectively.

Conclusions

Relapsed intracranial ependymoma has a poor prognosis despite multimodal therapy. Novel therapeutic strategies are desperately needed for this disease.
Synergistic enhancement of thermal conductivity by addition of graphene nanoplatelets to three‐dimensional boron nitride scaffolds for polyamide 6 composites
Authors: Wu Fangjuan , Chen Anlin , Pan Hanlu , Li Denghui , Zhang Lingjie , Fang Hui , Peng Xiangfang , Bekyarova Elena
Published: February 2021

Three‐dimensional boron nitride/graphene nanoplatelets (3D‐BN‐GNP) scaffolds were fabricated using an ice‐templating method and polyamide 6 (PA6)‐based composites were prepared by vacuum impregnation of caprolactam monomers into the scaffolds, followed by polymerization. The BN sheets in the PA6/3D‐BN and PA6/3D‐BN‐GNP composites display a predominant parallel alignment along the ice‐crystal formation constructing thermally conductive paths. The addition of few GNPs assists the dispersion of BN sheets in the PA6/3D‐BN‐GNP composites and repair the broken thermal paths caused by local agglomeration of the BN sheets. Consequently, GNPs play a morphology‐promoted synergistic role in the enhancement of the thermal conductivity of the PA6/3D‐BN‐GNP composites. The PA6/3D‐BN‐GNP composite prepared with 23.40 wt% BN sheets and 2.60 wt% GNPs exhibits the highest thermal conductivity of 2.80 W m−1 K−1, which is 833% and 33% higher than the values recorded for the pure PA6 and the PA6/3D‐BN composite at BN loading of 26.18 wt%, respectively. Infrared imaging analysis revealed that the surface of the PA6/3D‐BN‐GNP composite has a fast response to heating and cooling, suggesting the potential of the composites in thermal management applications.
Preparation of ordered macroporous molecularly imprinted polymers and their applications in purifying cinchona alkaloids from cinchona extract
Authors: Zhang Zhi‐Yuan , Rui Li‐Li , Lin Ya‐Li , Zhang Hui‐Dan , Ou Ji‐Ming , He Jian‐Feng , Wu Quan‐Zhou
Published: February 2021

Three‐dimensionally ordered macroporous molecularly imprinted polymers (3DOM MIPs) were prepared for the direct purification of cinchona alkaloids from crude cinchona extract. The 3DOM MIPs were easily prepared by grafting quinine‐MIPs on the pore walls of 3DOM thiol‐group‐functionalized silica. The materials were characterized using various techniques. The results showed that the 3DOM MIPs had a more regular macroporous structure, a greater surface area and a greater porosity than traditional bulk MIPs (TBMIPs). The 3DOM MIPs could reach a high MIP content of 69.9%. And the 3DOM structure could improve intraparticle adsorption and provide more accessible adsorption sites. Consequently, in both static adsorption experiments and solid‐phase extraction (SPE), the actual adsorption capacity of the imprinted polymers of the 3DOM MIPs was about 83% higher than that of TBMIPs. Moreover, the 3DOM MIPs exhibited high affinity for quinine, quinidine and cinchonine. Using the quinine‐3DOM MIPs as SPE sorbent, quinine, quinidine and cinchonine could be effectively purified from crude cinchona extract with high elution recoveries. Control experiments also showed that the 3DOM MIPs were superior to commercially available adsorbents in terms of the purification of cinchona alkaloids from crude extract. © 2021 Society of Chemical Industry
What and where are periglacial landscapes?
Authors: Murton Julian B.
Published: February 2021

Uncertainties about landscape evolution under cold, nonglacial conditions raise a question fundamental to periglacial geomorphology:what and where are periglacial landscapes?To answer this, with an emphasis on lowland periglacial areas, the present study distinguishes between characteristic and polygenetic periglacial landscapes, and considershow complete is the footprint of periglaciation?Using a conceptual framework of landscape sensitivity and change, the study applies four geological criteria (periglacial persistence, extraglacial regions, ice‐rich substrates, and aggradation of sediment and permafrost) through the last 3.5 million years of the late Cenozoic to identify permafrost regions in the Northern Hemisphere. In limited areas of unglaciated permafrost regions are characteristic periglacial landscapes whose morphology has been adjusted essentially to present (i.e., Holocene interglacial) process conditions, namely thermokarst landscapes, and mixed periglacial–alluvial and periglacial–deltaic landscapes. More widespread in past and present permafrost regions are polygenetic periglacial landscapes, which inherit ancient landsurfaces on which periglacial landforms are superimposed to varying degrees, presently or previously. Such landscapes comprise relict accumulation plains and aprons, frost‐susceptible and nonfrost‐susceptible terrains, cryopediments, and glacial–periglacial landscapes. Periglaciation can produce topographic fingerprints at mesospatial scales (103–105m): (1) relict accumulation plains and aprons form where long‐term sedimentation buried landsurfaces; and (2) plateaux with convexo–concave hillslopes and inset with valleys, formed by bedrock brecciation, mass wasting, and stream incision in frost‐susceptible terrain.
Feeling at home across time and place: A study of Ecuadorians in three European cities
Authors: Boccagni Paolo , Vargas‐Silva Carlos
Published: February 2021

International migration creates significant dilemmas for people to feel at home or not and a meaningful field to investigate this emotional experience. Using a cross‐country survey of Ecuadorians in Madrid, Milan and London (n = 1093), we explore how spatial, relational, infrastructural and emotional variables influence the sense of feeling at home in a place. We link these aspects to length of residence and the location's ‘connectedness’ to Ecuador. Immigrants' sense of feeling at home increases over time, regardless of location or scale. However, feeling at home is positively associated with the location's connectedness to Ecuador. The importance of social relations (especially inviting friends) and infrastructural characteristics for feeling at home in a place also increases over time, contrary to the influence of nostalgic homeland reminders. Overall, Ecuadorians attach a sense of home to their local context of settlement, more than to their homeland. Results are remarkably similar across genders.
Network model‐based screen for FDA‐approved drugs affecting cardiac fibrosis
Authors: Zeigler Angela C. , Chandrabhatla Anirudha S. , Christiansen Steven L. , Nelson Anders R. , Holmes Jeffrey W. , Saucerman Jeffrey J.
Published: February 2021

Cardiac fibrosis is a significant component of pathological heart remodeling, yet it is not directly targeted by existing drugs. Systems pharmacology approaches have the potential to provide mechanistic frameworks with which to predict and understand how drugs modulate biological systems. Here, we combine network modeling of the fibroblast signaling network with 36 unique drug‐target interactions from DrugBank to predict drugs that modulate fibroblast phenotype and fibrosis. Galunisertib was predicted to decrease collagen and α‐SMA expression, which we validated in human cardiac fibroblasts. In vivo fibrosis data from the literature validated predictions for 10 drugs. Further, the model was used to identify network mechanisms by which these drugs work. Arsenic trioxide was predicted to induce fibrosis by AP1‐driven TGFβ expression and MMP2‐driven TGFβ activation. Entresto (valsartan/sacubitril) was predicted to suppress fibrosis by valsartan suppression of ERK signaling and sacubitril enhancement of PKG activity, both of which decreased Smad3 activity. Overall, this study provides a framework for integrating drug‐target mechanisms with logic‐based network models, which can drive further studies both in cardiac fibrosis and other conditions.
Integrated and Portable Magnetometer Based on Nitrogen‐Vacancy Ensembles in Diamond
Authors: Stürner Felix M. , Brenneis Andreas , Buck Thomas , Kassel Julian , Rölver Robert , Fuchs Tino , Savitsky Anton , Suter Dieter , Grimmel Jens , Hengesbach Stefan , Förtsch Michael , Nakamura Kazuo , Sumiya Hitoshi , Onoda Shinobu , Isoya Junichi , Jelezko Fedor
Published: February 2021

Magnetic field sensors that exploit quantum effects have shown that they can outperform classical sensors in terms of sensitivity enabling a range of novel applications in future, such as a brain machine interface. Negatively charged nitrogen‐vacancy (NV) centers in diamond have emerged as a promising high sensitivity platform for measuring magnetic fields at room temperature. Transferring this technology from laboratory setups into products and applications, the total size of the sensor, the overall power consumption, and the costs need to be reduced and optimized. Here, a fiber‐based NV magnetometer featuring a complete integration of all functional components is demonstrated without using any bulky laboratory equipment. This integrated prototype allows portable measurement of magnetic fields with a sensitivity of 344 pT Hz−1/2.
David overshadows Goliath: Specializing in generality for internationalization in the global mobile money industry
Authors: Wormald Audra , Agarwal Rajshree , Braguinsky Serguey , Shah Sonali K.
Published: February 2021

ABSTRACT

Research Summary

We investigate the emergence of a global industry based on digital innovation by studying how the international expansion of pioneering firms relates to their characteristics and strategies for capability development and deployment. Using detailed archival data on mobile money, we classify pioneers that internationalize based on whether they were multinational diversifying entrants, developed country startups, or developing country startups. Our quantitative evidence suggests developing country startups that internationalize have the highest impact on the industry through subsequent platform launches. Digging deeper into the business histories of each firm, we uncover why: these startups “specialize in generality” by developing and deploying “bundled knowledge” capital consisting of technology, problem solving and alliance management capabilities, thereby offsetting their physical capital scale and scope disadvantages relative to multinational diversifying entrants.

Managerial Summary

Our study demonstrates how pioneers in mobile money created and utilized capabilities for international expansion. We show that among pioneers who engaged in internationalization, developing country startups had a greater global footprint than both developed country startups and diversifying entrant multinationals, even though conventional wisdom might predict greater impact for the latter two types. We link such impact of developing country startups to their focus on developing “bundled knowledge” capital, consisting of technology, problem solving, and alliance management capabilities which they could leverage in multiple countries. Not only did these firms grow through collaboration, they created and democratized access to needed financial services worldwide.
Biomimetic nanoporous aerogels from branched aramid nanofibers combining high heat insulation and compressive strength
Authors: Li Jun , Li Huaiyu , Xu Liwei , Wang Lijun , Hu Zhen , Liu Li , Huang Yudong , Kotov Nicholas A.
Published: February 2021

Materials combining efficient thermal insulation and high mechanical properties are needed in many areas of technology. Various aerogels provide a convenient design framework for thermal insulators, but they are often brittle. Furthermore, the spectrum of advanced properties is constantly expanding while requirements to the degree of control of the three‐dimensional gel‐forming network is constantly increasing. Here, we report on biomimetic aramid nanofibers aerogels with the structure replicating articular cartilage, prepared by supercritical drying of 3D networks held together by hydrogen bonds. Owing to the branching morphology of the nanofibers, the three‐dimensional nanoscale networks with extensive percolation and high interconnectivity can be obtained. The aerogels showed high porosity with an average open pore size of 21.5 nm and correspondingly low specific density of 0.0081 g/cm3. The aerogels also possess a high compressive strength of 825 kPa at a strain of 80%. Due to the unique aramid chemistry of the parent nanofibers, aramid aerogels combine low thermal conductivity of 0.026 W/m·K with high thermal stability up to 530°C, which is unusually high for polymeric and composite materials of any type, opening a broad range of applications from electronics to space travel.
Incentivizing provision of collective goods: Allocation rules
Authors: Stoddard Brock V. , Cox Caleb A. , Walker James M.
Published: February 2021

In a laboratory experiment, we study the voluntary provision of a divisible collective good. Allocations of the collective good to group members are determined by a third party “allocator” who benefits from increased provision of the collective good, but is rewarded externally. The allocator may resolve the free‐rider problem inherent in provision by assigning shares of the collective good to incentivize cooperation. The flexibility in allocations available to the allocator is varied across three treatment conditions. The highest level of collective good provision is observed within some groups in the mechanism that allows the allocator the greatest flexibility. However, greater flexibility comes at the cost of higher variance in allocation decisions by some allocators, leading to lower levels of provision in some groups.
Spectroscopic methods to quantify molecules of the heme‐biosynthesis pathway: A review of laboratory work and point‐of‐care approaches
Authors: Heckl Christian , Eisel Maximilian , Lang Alexander , Homann Christian , Paal Michael , Vogeser Michael , Rühm Adrian , Sroka Ronald
Published: February 2021

Spectroscopic methods for quantitative detection of molecules of the heme synthesis and heme metabolism are presented. This can be used to diagnose disease patterns such as iron deficiency, porphyria or free hemoglobin. This article combines an overview of clinical conditions associated with disorders of heme biosynthesis and presents selected laboratory findings in the development of portable diagnostic devices. An iron deficiency measurement device has already been validated as a portable device in clinical trials, two other methods have been tested according to EMA guidelines and are available for use in clinical validation studies. The presented rapid, low‐cost and low‐effort methods can support diagnosis in everyday clinical practice and initiate more targeted therapies, even for rare disease conditions.

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Calcium oxalate urolithiasis in juvenile dogs
Authors: Saver Alexander , Lulich Jody P. , Van Buren Samantha , Furrow Eva
Published: February 2021

Background: The features of juvenile‐onset calcium oxalate urolithiasis in dogs have not been previously reported.

Methods: Calcium oxalate urolith submissions to the Minnesota Urolith Center between 2012 and 2016 were analyzed to identify those originating from juvenile (≤2 years, n = 510) or mature (7–9 years, n = 39,093) dogs. Breed, sex, urolith salt type and urolith location were compared between groups. Breeds represented in both groups were also compared with respect to sex, urolith salt type and urolith location.

Results: French (odds ratios [OR] = 14.7, p < 0.001) and English (OR = 14.3, p < 0.001) Bulldogs were overrepresented in juvenile submissions. All juvenile French and English Bulldogs were male. Across all breeds, juvenile dogs were more likely to be male (89%, p < 0.001) than mature dogs (79%). Juvenile dogs were also more likely to form dihydrate stones compared to mature dogs (33% versus 14%, respectively; p < 0.001). Breed differences were discovered in sex, urolith salt type and stone location.

Conclusions: French and English Bulldogs comprise a greater proportion of juvenile calcium oxalate urolith submissions than expected based on their rarity in mature submissions. Inherited risk factors, particularly X chromosome variants, should be investigated due to the strong breed and sex predispositions identified.
Modulation of nociception by amitriptyline hydrochloride in the Speke’s hinge‐back tortoise (Kiniskys spekii)
Authors: Makau Christopher M. , Towett Philemon K. , Abelson Klas S.P. , Kanui Titus I.
Published: February 2021

Background

There are limited studies on the utilization of analgesics in testudines. Management of pain in reptiles is by use of analgesics generally used in other vertebrate species. Evidently, some analgesics considered to be generally effective in reptiles are not effective in certain reptile species.

Objective

The purpose of this study was to examine the effect of amitriptyline hydrochloride on nociceptive behaviour in Speke's hinge‐back tortoise.

Methods

Twenty‐four adult Speke‐hinged tortoises weighing 500–700 g were used. The effects of amitriptyline hydrochloride on nociception were evaluated using the formalin, capsaicin and hot plate nociceptive tests. Amitriptyline was administered intracoelomically at doses of 0.5, 1.0 and 3.0 mg/kg.

Results

The higher doses of amitriptyline hydrochloride caused an increase in nociceptive behaviour (time spent in hindlimb withdrawal) on the formalin and capsaicin nociceptive tests, suggesting a potentiating effect. However, the doses used had no significant change in nociceptive behaviour on withdrawal response in the hot plate test.

Conclusions

The study showed that amitriptyline hydrochloride which is widely used in management of neuropathic pain potentiates nociceptive effects in the formalin and capsaicin nociceptive tests in the Speke's hinge‐back tortoise. The hot plate test, which previously has not been reported in these animals, gave results not in line with the other tests and therefore more testing and validation of the test is required. Amitriptyline modulates chemical and thermal pain differently.
Moderating the Impact of Nurse Emigration on the Health Sector: The State and Policy Instrument Choice
Authors: Cabanda Exequiel
Published: February 2021

This paper offers an unconventional approach to the migration‐development nexus by zooming in on the health sector. Although state strategies promoting nurse migration are widely studied, comprehension on how the state functions as a central actor in emigration is empirically deficient in accounting for the different development levels experienced by sending countries. Drawing from the literature on policy instrument choice, this paper examines how the Philippines as the leading nurse sending state in the world intervenes in the emigration of Filipino nurses and what are the effects of these interventions? Based on a key informant survey (N = 100), regression results show that the state's regulatory authority in the remittance market triggers the positive contribution of nurse remittances on health sector development. This paper concludes by discussing how the choice of policy instruments is a crucial decision point for nurse‐sending countries when maximizing the development impact of emigration on the health sector.
Systematic investigation of new alkaline earth phosphonates based on the linker molecule N,N’‐4,4’‐bipiperidine‐bis(methylenephosphonic acid)
Authors: Steinke Felix , Stock Norbert
Published: February 2021

A systematic study of the systems M2+/H4L/KOH/H2O, with M2+=Mg2+, Ca2+, Sr2+, Ba2+ and H4L=N,N’‐4,4’‐bipiperidine‐bis(methylenephosphonic acid) was carried out using high‐throughput methods, including a temperature gradient oven. Overall, six new alkaline earth phosphonates were discovered and structurally characterised by single‐crystal and powder X‐ray diffraction. At room temperature the compounds of composition [Mg2(H2O)8(L)] (1), [Ca2(H2O)6(L)] (2), [Sr2(H2O)4(L)] (3) and [Ba2(H2O)9(L)] ⋅ H2O (4) were discovered. They exhibit the same metal to linker ratio, but differ in their water content. Distinct structural changes are observed with an increase in dimensionality of the coordination polymer with increasing ionic radius of the metal ion. At elevated reaction temperatures the two new metal phosphonates [Mg2(H2O)5(L)] (5) and [Ba2(H2O)2(L)] ⋅ 2 H2O (6) were obtained either from the same reaction mixture as for 1 and 4, respectively, or by solid state transformation. The detailed characterisation of the all materials is also reported.
Three new Cd(II)/Zn(II) coordination polymers assembled via dual‐ligand strategy: crystal structures and luminescent properties
Authors: Liu Yi , Zhao Xiao‐han , Guo Li‐da , Wang Bing , Li Fei‐ping , Cao Jin‐jin , Li Wen‐hong , Song Ying
Published: February 2021

Dual‐ligand strategy was used to synthesize three new coordination polymers with the formula as [Cd(HL)(2,2’‐bipy)]n⋅n(H2O) (1), [Cd3(L)2(bib)3(H2O)]n (2), [Zn(HL)(2,2’‐bipy)]n (3) (H3L=biphenyl‐3,4’,5‐tricarboxylic acid, 2,2’‐bipy=2, 2’‐bipyridine, bib=1,4‐bis(imidazol‐1‐yl)butane), which were further structurally characterized by single crystal X‐ray diffraction analyses. Compound 1 features a 1D infinite chain structure and π…π interactions between adjacent 1D chains gives rise to a 2D layer and further O−H…O hydrogen bonding interactions between adjacent 2D layers affords a 3D supramolecular framework. Compound 2 shows a 3D framework with unprecedented (3,4)‐connected topology. Compound 3 features a 2D→3D interdigitated supramolecular framework based on 2D hydrogen‐bonding layers that constructed from 1D infinite chain and interchain O−H…O hydrogen bonding interactions. Luminescence investigations revealed that compound 1 shows interesting tunable luminescence via altering the excitation wavelength, and compound 2–3 show intense unimodal emission luminescence at room temperature.