bluuebunny/crossref_metadata_2025 huggingface dataset:
A new approach for the synthesis of spiro and gem‐dimethyl‐substituted 1,4‐oxazepines from N‐propargylic β‐enaminones
Authors: Karadeniz Eda , Kelgokmen Yilmaz , Zora Metin
Published: November 2020

An efficient and general method for the synthesis of spiro‐1,4‐oxazepines and 3,3‐dimethyl‐1,4‐oxazepines is reported. When treated with ZnI2 and AgSbF6 in refluxing DCE, cyclohexane‐embedded N‐propargylic β‐enaminones underwent 7‐exo‐dig cyclization to afford spiro‐1,4‐oxazepines, specifically 12‐methylene‐11‐oxa‐7‐azaspiro[5.6]dodeca‐7,9‐dienes, in good to high yields. Accordingly, N‐(1,1‐dimethyl)propargylic β‐enaminones produced 3,3‐dimethyl‐1,4‐oxazepines. Cyclization was found to be general for a diverse range of N‐propargylic β‐enaminones with high efficiency and broad functional group tolerance. This operationally easy method might provide quick access to a library of functionalized spiro and gem‐dimethyl‐substituted 1,4‐oxazepine derivatives of pharmacological interest.
Expression of tyrosine pathway enzymes in mice demonstrates that homogentisate 1,2‐dioxygenase deficiency in the liver is responsible for homogentisic acid‐derived ochronotic pigmentation
Authors: Wilson Peter J. M. , Ranganath Lakshminarayan R. , Bou‐Gharios George , Gallagher James A. , Hughes Juliette H.
Published: November 2020

Alkaptonuria (AKU) is caused by homogentisate 1,2‐dioxygenase (HGD) deficiency. This study aimed to determine if HGD and other enzymes related to tyrosine metabolism are associated with the location of ochronotic pigment. Liver, kidney, skin, bone, brain, eyes, spleen, intestine, lung, heart, cartilage, and muscle were harvested from 6 AKU BALB/c Hgd−/− (3 females, 3 males) and 4 male C57BL/6 wild type (WT) mice. Hgd, 4‐hydroxyphenylpyruvate dioxygenase (4‐Hppd), tyrosine hydroxylase (Th), and tyrosinase (Tyr) mRNA expression was investigated using qPCR. Adrenal gland and gonads from AKU Hgd tm1a −/− mice were LacZ stained, followed by qPCR analysis of Hgd mRNA. The liver had the highest expression of Hgd, followed by the kidney, with none detected in cartilage or brain. Low‐level Hgd expression was observed within developing male germ cells within the testis and epididymis in Hgd tm1a −/−. 4‐Hppd was most abundant in liver, with smaller amounts in kidney and low‐level expression in other tissues. Th was expressed mainly in brain and Tyr was found primarily in the eyes. The tissue distribution of both Hgd and 4‐Hppd suggest that ochronotic pigment in AKU mice is a consequence of enzymes within the liver, and not from enzymatic activity within ochronotic tissues. Excessive accumulation of HGA as ochronotic pigment in joints and other connective tissues originates from the circulation and therefore the extracellular fluid. The tissue distribution of both Th and Tyr suggests that these enzymes are not involved in the formation of HGA‐derived ochronotic pigment.
Reproducibility of Aorta Segmentation on 4D Flow MRI in Healthy Volunteers
Authors: Juffermans Joe F. , Westenberg Jos J.M. , van den Boogaard Pieter J. , Roest Arno A.W. , van Assen Hans C. , van der Palen Roel L.F. , Lamb Hildo J.
Published: November 2020

Background

Hemodynamic aorta parameters can be derived from 4D flow MRI, but this requires lumen segmentation. In both commercially available and research 4D flow MRI software tools, lumen segmentation is mostly (semi‐)automatically performed and subsequently manually improved by an observer. Since the segmentation variability, together with 4D flow MRI data and image processing algorithms, will contribute to the reproducibility of patient‐specific flow properties, the observer's lumen segmentation reproducibility and repeatability needs to be assessed.

Purpose

To determine the interexamination, interobserver reproducibility, and intraobserver repeatability of aortic lumen segmentation on 4D flow MRI.

Study Type

Prospective and retrospective.

Population

A healthy volunteer cohort of 10 subjects who underwent 4D flow MRI twice. Also, a clinical cohort of six subjects who underwent 4D flow MRI once.

Field Strength/Sequence

3T; time‐resolved three‐directional and 3D velocity‐encoded sequence (4D flow MRI).

Assessment

The thoracic aorta was segmented on the 4D flow MRI in five systolic phases. By positioning six planes perpendicular to a segmentation's centerline, the aorta was divided into five segments. The volume, surface area, centerline length, maximal diameter, and curvature radius were determined for each segment.

Statistical Tests

To assess the reproducibility, the coefficient of variation (COV), Pearson correlation coefficient (r), and intraclass correlation coefficient (ICC) were calculated.

Results

The interexamination and interobserver reproducibility and intraobserver repeatability were comparable for each parameter. For both cohorts there was very good reproducibility and repeatability for volume, surface area, and centerline length (COV = 10–32%, r = 0.54–0.95 and ICC = 0.65–0.99), excellent reproducibility and repeatability for maximal diameter (COV = 3–11%, r = 0.94–0.99, ICC = 0.94–0.99), and good reproducibility and repeatability for curvature radius (COV = 25–62%, r = 0.73–0.95, ICC = 0.84–0.97).

Data Conclusion

This study demonstrated no major reproducibility and repeatability limitations for 4D flow MRI aortic lumen segmentation.

Level of Evidence

3

Technical Efficacy Stage

2
Predicting Isocitrate Dehydrogenase (IDH)Mutation Status in Gliomas Using MultiparameterMRIRadiomics Features
Authors: Peng Hong , Huo Jiaohua , Li Bo , Cui Yuanyuan , Zhang Hao , Zhang Liang , Ma Lin
Published: November 2020

Background

Accurate and noninvasive detection of isocitrate dehydrogenase (IDH, including IDH1 and IDH2) status is clinically meaningful for molecular stratification of glioma, but remains challenging.

Purpose

To establish a model for classifying IDH status in gliomas based on multiparametric MRI.

Study Type

Retrospective, radiomics.

Population

In all, 105 consecutive cases of grade II–IV glioma with 50 IDH1 or IDH2 mutant (IDHm) and 55 IDH wildtype (IDHw) were separated into a training cohort (n =73) and a test cohort (n =32).

Field Strength/Sequence

Contrast‐enhanced T1‐weighted (CE‐T1W), T2‐weighted (T2W), and arterial spin labeling (ASL) images were acquired at 3.0T.

Assessment

Two doctors manually labeled the volume of interest (VOI) on CE‐T1W, then T2W and ASL were coregistered to CE‐T1W. A total of 851 radiomics features were extracted on each VOI of three sequences. From the training cohort, all radiomics features with age and gender were processed by the Mann–WhitneyU‐test, Pearson test, and least absolute shrinkage and selection operator to obtain optimal feature groups to train support vector machine models. The accuracy and area under curve (AUC) of all models for classifying the IDH status were calculated on the test cohort. Two subtasks were performed to verify the efficiency of texture features and the Pearson test in IDH status classification, respectively.

Statistical Tests

The permutation test with Bonferroni correction; chi‐square test.

Results

The accuracy and AUC of the classifier, which combines the features of all three sequences, achieved 0.823 and 0.770 (P < 0.05), respectively. The best model established by texture features only had an AUC of 0.819 and an accuracy of 0.761. The best model established without the Pearson test got an AUC of 0.747 and an accuracy of 0.719.

Data Conclusion

IDH genotypes of glioma can be identified by radiomics features from multiparameter MRI. The Pearson test improved the performance of the IDH classification models.

Level of Evidence

4

Technical Efficacy Stage

1
Numerical solution ofVolterra‐Fredholmintegral equation via hyperbolic basis functions
Authors: Esmaeili Hamid , Rostami Majid , Hooshyarbakhsh Vahideh
Published: November 2020

In this paper, a new method using hyperbolic basis functions is presented to solve second kind linear Volterra‐Fredholm integral equation. In other words, our method approximates the solution of a Volterra‐Fredholm integral equation by the hyperbolic basis functions, which produce block‐pulse functions. Hence, the new method reduces the linear Volterra‐Fredholm integral equation to a system of algebraic equations. Some numerical examples are provided to illustrate the computational efficiency and accuracy of the new method.
Anti‐VEGF antibody delivered locally reduces bony bar formation following physeal injury in rats
Authors: Erickson Christopher B. , Newsom Jake P. , Fletcher Nathan A. , Yu Yangyi , Rodriguez‐Fontan Francisco , Weatherford Shane A. , Hadley‐Miller Nancy , Krebs Melissa D. , Payne Karin A.
Published: November 2020

Physeal injuries can result in the formation of a “bony bar” which can lead to bone growth arrest and deformities in children. Vascular endothelial growth factor (VEGF) has been shown to play a role in bony bar formation, making it a potential target to inhibit bony repair tissue after physeal injury. The goal of this study was to investigate whether the local delivery of anti‐VEGF antibody (α‐VEGF; 7.5 μg) from alginate:chitosan hydrogels to the tibial physeal injury site in rats prevents bony bar formation. We tested the effects of quick or delayed delivery of α‐VEGF using both 90:10 and 50:50 ratio alginate:chitosan hydrogels, respectively. Male and female 6‐week‐old Sprague‐Dawley rats received a tibial physeal injury and the injured site injected with alginate‐chitosan hydrogels: (1) 90:10 (Quick Release); (2) 90:10 + α‐VEGF (Quick Release + α‐VEGF); (3) 50:50 (Slow Release); (4) 50:50 +  α‐VEGF (Slow Release +  α‐VEGF); or (5) Untreated. At 2, 4, and 24 weeks postinjury, animals were euthanized and tibiae assessed for bony bar and vessel formation, repair tissue type, and limb lengthening. Our results indicate that Quick Release + α‐VEGF reduced bony bar and vessel formation, while also increasing cartilage repair tissue. Further, the quick release of α‐VEGF neither affected limb lengthening nor caused deleterious side‐effects in the adjacent, uninjured physis. This α‐VEGF treatment, which inhibits bony bar formation without interfering with normal bone elongation, could have positive implications for children suffering from physeal injuries.
Outcomes after antibiotic megaspacer implantation in patients with severe chronic periprosthetic infections
Authors: Amin Sheena J. , Patel Raj M. , Gutowski Christina J. , Kim Tae Won B.
Published: November 2020

Periprosthetic joint infection (PJI) is a rare postoperative complication that is treated with antibiotic spacers. Some patients develop severe, treatment‐resistant, chronic PJI despite multiple attempts at salvaging the joint. Permanent resection of the joint or amputation may be the only definitive treatment. The purpose of this study is to describe the outcomes, infection resolution rate, and complications of two‐stage revision, utilizing extensive resection of the affected bone and application of antibiotic megaspacers as a modality for limb‐salvage. A review of 12 patients, initially referred for amputation due to chronically failed PJI, was conducted. All patients underwent extensive resection of the bone and surgical implantation of a custom‐made antibiotic megaspacer between December 2016 and June 2019. Thirteen megaspacers were placed in 13 infected joints in 12 patients with a history of chronic PJI. Six patients (50%) had a diagnosis of osteomyelitis. Eradication of the infection leading to limb‐salvage was successful in nine patients. Visual Analog Scale pain scores improved by 3.5, or 50%, after two‐stage revision with megaprosthesis reimplantation (p = .008), and six patients (54.5%) had improvement in ambulation. Complication rates, not including reinfection or recurrence, following megaspacer and megaprosthesis reimplantation were 58.3% and 27.3%, respectively. One patient underwent amputation due to a life‐threatening infection while two other patients underwent amputation due to debilitating complications following limb‐salvage surgery. Statement of Clinical Significance: In patients whose PJI becomes treatment‐resistant after multiple failed attempts at traditional two‐stage exchange, performing extensive boney resection with placement of an antibiotic‐laden megaspacer can be an effective method of achieving limb‐salvage.
Initial displacement of the intra‐articular surface after articular fracture correlates with PTA in C57BL/6 mice but not “superhealer” MRL/MpJ mice
Authors: Vovos Tyler J. , Furman Bridgette D. , Huebner Janet L. , Kimmerling Kelly A. , Utturkar Gangadhar M. , Green Cynthia L. , Kraus Virginia B. , Guilak Farshid , Olson Steven A.
Published: November 2020

Posttraumatic arthritis (PTA) occurs commonly after articular fracture and may arise, in part, from joint surface incongruity after injury. MRL/MpJ (MRL) “super‐healer” mice are protected from PTA compared to C57BL/6 (B6) mice following articular fracture. However, the relationship between the initial displacement of the articular surface, biologic response, and susceptibility to PTA after fracture remains unclear. The objective of this study was to assess whether joint incongruity after articular fracture, as measured by in vivo micro‐computed tomography (microCT), could predict pathomechanisms of PTA in mice. B6 and MRL mice (n = 12/strain) received a closed articular fracture (fx) of the left tibial plateau. Articular incongruity was quantified as bone surface deviations (BSD) for each in vivo microCT scan obtained from pre‐fx to 8 weeks post‐fx, followed by histologic assessment of arthritis. Serum concentrations of bone formation (PINP) and bone resorption (CTX‐I) biomarkers were quantified longitudinally. Both strains showed increases in surface incongruity over time, as measured by increases in BSD. In B6 mice, acute surface incongruity was significantly correlated to the severity of PTA (R
2 = 0.988; p = .0006), but not in MRL mice (R
2 = 0.224; p = .220). PINP concentrations significantly decreased immediately post‐fx in B6 mice (p = .023) but not in MRL mice, indicating higher bone synthesis in MRL mice. MRL/MpJ mice demonstrate a unique biologic response to articular fracture such that the observed articular bone surface displacement does not correlate with the severity of subsequent PTA. Clinical Relevance: Identifying therapies to enhance acute biologic repair following articular fracture may mitigate the risk of articular surface displacement for PTA.
Correlation of PRL3 expression with colorectal cancer progression
Authors: Leiphrakpam Premila D. , Lazenby Audrey J. , Smith Lynette M. , Brattain Michael G. , Black Jennifer D. , Wang Jing , Are Chandrakanth
Published: November 2020

Objectives

To evaluate the relationship between phosphatase of regenerating liver 3 (PRL3) expression and clinical outcome in colorectal cancer (CRC).

Background

PRL3, a protein tyrosine phosphatase functions as one of the key regulatory enzymes of various signal transduction pathways. PRL3 is highly expressed in a majority of cancers and is a novel potential therapeutic target.

Methods

PRL3 expression was evaluated by immunohistochemistry in 167 patients with CRC, 37 patients with no disease, and 26 patients with metastatic CRC (mCRC). Phosphorylated Akt at serine 473 (p‐Akt S473) expression was also evaluated by immunohistochemistry in mCRC patients.

Results

High expression of PRL3 was correlated with CRC progression, and every one unit increase in PRL3 level contributed to an increase in the rate of death by 1%–1.7%. PRL3 expression was significantly higher in liver metastases compared with primary tumors and showed a significant positive correlation with the expression level of p‐Akt S473.

Conclusion

PRL3 expression levels associated with CRC progression and metastasis, and positively correlated with activated Akt level in mCRC. Together, these findings indicated that PRL3 might be a potential marker for increased risk of CRC‐specific tumor burden and identify PRL3 as an attractive therapeutic target for mCRC treatment.
Low‐dose liquid cell electron microscopy investigation of the complex etching mechanism of rod‐shaped silica colloids
Authors: Sadighikia Sina , Grau‐Carbonell Albert , Welling Tom A.J. , Kotni Ramakrishna , Hagemans Fabian , Imhof Arnout , van Huis Marijn A. , van Blaaderen Alfons
Published: November 2020

Understanding the chemical structure of rod‐shaped silica colloidal particles is attainable by investigating their etching mechanism in solution. Liquid Cell (Scanning) Transmission Electron Microscopy (LC‐(S)TEM) is a promising technique through which the etching of these particles can be observed in real time, and at the single particle level, without possible deformations induced by the surface tension of dried particles. However, the presence of high energy electrons, and the different geometry in LC experiments may alter the conditions of in situ experiments compared to their ex situ counterparts. Here we present a controlled low‐dose LC‐STEM study of the basic etching process of micron‐sized silica rods that are immobilized on the SiN window of a liquid cell. The results show that using low‐dose imaging conditions, combined with a low accumulated electron dose, and optimized flow rates of solutions allow for investigation of the chemical etching mechanism of silica colloidal particles using the LC‐(S)TEM technique with negligible effects of the electron beam. A comparison of ex situ etching experiments with LC‐STEM observations show that the LC geometry can play a crucial role in LC‐STEM experiments where the diffusion of the etching particles is important, which should be considered during the interpretations of LC‐STEM results.
Sex Affects Regional Variations in Subcutaneous Adipose Tissue T Cells but not Macrophages in Adults with Obesity
Authors: Murphy Jessica , Delaney Kerri Z. , Dam Vi , Tam Bjorn T. , Khor Natalie , Tsoukas Michael A. , Morais José A. , Santosa Sylvia
Published: November 2020

Objective

The inflammatory environment in lower‐body subcutaneous adipose tissue (SAT) has been largely unexplored. This study aimed to examine the effects of region (upper body vs. lower body) and sex on SAT immune cell profiles in young adults with obesity.

Methods

Abdominal (AB) and femoral (FEM) SAT was collected from 12 males (mean [SEM] age = 30.8 [1.4] years; mean [SEM] BMI = 34.1 [1.1] kg/m2) and 22 females (mean [SEM] age = 30.6 [0.6] years; mean [SEM] BMI = 34.0 [0.7] kg/m2) with obesity via needle aspiration. Flow cytometry was used to quantify macrophage (CD68+) and T‐cell (CD3+) subpopulations in the stromovascular fraction of each SAT region.

Results

Females had a greater proportion of most T‐cell types (CD3+CD4+CD45RA+, CD3+CD4+CD45RA−, and CD3+CD8+CD45RA+) in FEM compared with AB SAT, while males had similar proportions in both regions. Regardless of sex, the M1‐like macrophage population (CD68+CD206−) was proportionally higher in AB SAT than in FEM SAT.

Conclusions

Results showed that T‐cell populations vary by SAT region in females but not males. Both sexes, however, have proportionately more proinflammatory macrophages in upper‐body than in lower‐body SAT. It remains to be seen how these unique immune cell profiles in males and females with obesity contribute to adipose tissue inflammation and metabolic disease risk.
Sensing of fluoride anion based on desilylation and intramolecular charge transfer of 2‐[2‐(tert‐butyl‐diphenyl‐silanyloxy)‐phenyl]‐4,5‐diphenyl‐1H‐imidazole
Authors: Yang Guang , Wang Gang , Chen Kaifeng , Yang Dapeng
Published: November 2020

In view of the tremendous potential for fluorescent chemosensors, more and more people pay attention to design and synthesize high‐efficiency sensors. Given the importance of fluorescence response mechanism, in the present work, the specific sensing mechanism of a novel fluoride anion chemosensor 2‐[2‐(tert‐butyl‐diphenyl‐silanyloxy)‐phenyl]‐4,5‐diphenyl‐1H‐imidazole (abbreviated as TBDI) has been investigated based on density functional theory (DFT) and time‐dependent DFT (TDDFT) methods. Our theoretical electronic spectra (vertical excitation energies and fluorescence emission peaks) reproduced previous experimental results (Sensor Actuat B‐Chem. 2016, 232, 175), which confirms the rationality of our theoretical level adopted in this work. The constructed potential energy curve about fluoride‐triggered desilylation reaction suggests that the low barrier could be responsible for the rapid response to fluoride anion. Analyses about binding energies demonstrate that only fluoride anion could be detected for TBDI chemosensor in dimethyl sulfoxide (DMSO) solvent. In view of the vertical excitation process, the strong intramolecular charge transfer (ICT) process between the S0‐state and S1‐state transition explains the redshift of absorption peak for TBDI sensor with the addition of fluoride anion. This work not only presents a straightforward sensing mechanism of fluoride anion for TBDI sensor but also plays important roles in synthesizing and designing fluorescent chemosensors in future.
Longitudinal changes in physical activity levels and fear of falling after hip fracture
Authors: Tu Chang‐Yin , Shields Nora , Gill Stephen D. , Tacey Mark , Lindner Christopher , Hill Keith D.
Published: November 2020

Background and purpose

Due to global ageing, more people will suffer from hip fracture in the future, and many will be left with permanent physical impairments. The care burden for people post hip fracture is high. The aim of this study is to measure longitudinal changes in physical activity levels and fear of falling in people after hip fracture who return home after inpatient rehabilitation.

Methods

Longitudinal observational study. Participants were recruited from three rehabilitation centres in Victoria, Australia. Self‐reported fear of falling (Short Falls Efficacy Scale – International) and physical activity levels (Human Activity Profile – Adjusted Activity Score and Frenchay Activity Index) were assessed at 2 weeks, 3 and 6 months after discharge. Mobility (walking speed) and balance (Timed Up‐and‐Go test and Step Test) were measured at discharge from rehabilitation.

Results

Thirty‐four participants (mean age: 82 years [SD 8]; 62% female) with unilateral hip fracture were recruited. Participants had moderately impaired balance and mobility at discharge compared to age‐matched normative data; they were all discharged with a walking aid and were 40% slower in their walking speed. Participants had increased fear of falling and reduced physical activity 2 weeks after discharge, which improved significantly (p < 0.01) over the following 6 months, but scores were still lower than the normative values. At 6 months, participants also had moderate to high levels of fear of falling and were less active than the general population of similar age.

Discussion

Although fear of falling and physical activity improved in the 6 months following discharge, both remained negatively affected compared to normative data. Rehabilitation post hip fracture should include routine assessment of fear of falling as a potential barrier for return of physical activities.
Templates for writing PyMOL scripts
Authors: Mooers Blaine H. M. , Brown Marina E.
Published: November 2020

PyMOL commands are used to exert exquisite control over the appearance of a molecular model. This control has made PyMOL popular for making images of protein structures for publications and presentations. However, many users have poor recall of the commands due to infrequent use of PyMOL. This poor recall hinders the writing of new code in scripts. One solution is to build the new script by using code fragments as templates for modular parts of the task at hand. The code fragments can be accessed from a library while writing the code from inside a text editor (e.g., Visual Studio Code, Vim, and Emacs). We developed a library of PyMOL code templates or snippets called pymolsnips to ease the writing of PyMOL code in scripts. We made pymolsnips available on GitHub in formats for 18 popular text editors. Most of the supported text editors are available for Mac, Windows, and Linux operating systems. The GitHub site includes animations that complement the instructions for installing the library for each text editor. We expect that the library will help many PyMOL users to be more productive when writing PyMOL script files.
An extensible network slicing framework for satellite integration into 5G
Authors: Drif Youssouf , Chaput Emmanuel , Lavinal Emmanuel , Berthou Pascal , Tiomela Jou Boris , Grémillet Olivier , Arnal Fabrice
Published: November 2020

With the imminent deployment of the 5th generation (5G) mobile network in the nonstand‐alone version, some researches focus on network slicing to fully exploit the 5G infrastructure and achieve a highest level of flexibility in the network. This level of flexibility offered by the network slicing paradigm also fits the need of satellite networks in which satellite network operators (SNOs) want to offer 5G connectivity services additionally to the traditional satellite connectivity. However, the work that has been done so far for network slicing in 5G does not directly apply to satellite networks due to satellite architecture specificities and thus needs to be extended. We extend the work on network slicing and this paper proposes a novel Satellite Slicing Framework in order to fully exploit the satellite infrastructure and to facilitate the integration of satellite services into 5G. Our framework includes defining, modeling, orchestrating, and deploying multiple satellite network slices and their associated network services on top of mutualized satellite infrastructures.
Target‐Induced Core–Satellite Nanostructure Assembly Strategy for Dual‐Signal‐On Fluorescence Imaging and Raman Quantification of Intracellular MicroRNA Guided Photothermal Therapy
Authors: Li Na , Shen Fuzhi , Cai Zhiheng , Pan Wenzhen , Yin Yiming , Deng Xuan , Zhang Xing , Machuki Jeremiah Ong'achwa , Yu Yanyan , Yang Dongzhi , Yang Yun , Guan Ming , Gao Fenglei
Published: November 2020

Integrating biological detection and treatment into one system is a smart therapeutic maneuver for efficient cancer treatment. Herein, a target‐activated core–satellite nanostructure (CS nanostructure) assembly built on gold nanobipyramids motor (AuNBPs motor)/gold nanoparticle probe (AuNP probe) exhibiting simultaneous dual signal‐on imaging, quantification of intracellular microRNA‐21 (miR‐21), and photothermal therapy (PTT) for cancer is designed. Of note, when the AuNBPs motor/AuNP probe enters into cells, miR‐21 triggers the reaction between AuNBPs motor and AuNP probe, resulting in the formation of CS nanostructure assembly. The process of assembling the CS nanostructure is accompanied with strong fluorescent signals from TAMRA and surface‐enhanced Raman scattering (SERS) signals from adenine. The fluorescent signal is leveraged to image the intracellular miR‐21 level, whereas the SERS signal is utilized for absolute quantification of intracellular miR‐21, and the CS nanostructure acts as the photosensitizer for PTT. This strategy can successfully image and quantify miR‐21 in a single cell, and also distinguish normal cells from tumor cells. Moreover, under the guidance of fluorescence signal, the assembly kills tumor cells and inhibits tumor growth via PTT. In vitro and in vivo results prove that the proposed strategy possesses enormous potential for application in the diagnosis and treatment of cancer.
Feeling the Squeeze: Adult Run Size and Habitat Availability Limit Juvenile River Herring Densities in Lakes
Authors: Devine Matthew T. , Rosset Julianne , Roy Allison H. , Gahagan Benjamin I. , Armstrong Michael P. , Whiteley Andrew R. , Jordaan Adrian
Published: November 2020

Maximum densities of juvenile river herring (Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis) vary among freshwater lakes, likely due to densities of adult spawners. Differences in habitat availability and lake water quality may also contribute to variation in juvenile river herring productivity between populations, yet these relationships have not been tested across a large geographic scope. In this study we investigated relationships between juvenile river herring densities and (1) spawning adult river herring densities, (2) lake habitat availability, and (3) lake water quality in 29 freshwater lakes in the northeastern USA. Purse seines were used at night to sample juvenile river herring monthly in June–August 2014 and 2015, with concurrent collection of lake‐specific physical (e.g., lake surface area, mean depth, depth to thermocline), chemical (e.g., nitrogen, phosphorus, dissolved organic carbon [DOC]), and biological (chlorophyll a, adult spawning density) data. Spawning adult density (number of adults per surface area of lake) explained 66.6% of the variation in juvenile densities using a generalized additive model. Juvenile densities increased with increasing adult density, peaking at roughly 1,000 adults/ha, and then declined at higher adult densities, suggesting a limit to carrying capacity in juvenile production. Linear mixed‐effects models revealed that differences in water quality and habitat across lakes explained additional variation in juvenile densities. Specifically, DOC was negatively related to juvenile densities, suggesting that DOC limits the amount of suitable, well‐oxygenated epilimnion habitat available to juvenile river herring in late summer. Our results can be used to help understand expected juvenile production based on adult density within a lake, to inform expectations about juvenile growth and survival, and to understand the mechanisms for how changes in habitat availability and water quality affect river herring populations.
Catalytic Deoxygenation of Xylitol to Renewable Chemicals: Advances on Catalyst Design and Mechanistic Studies
Authors: Xia Qi , Jin Xin , Zhang Guangyu , Liu Mengyuan , Wang Jinyao , Li Yushan , Fang Tianqi , Ding Jie , Zhang Dongpei , Meng Kexin , Chen Xiaobo , Yang Chaohe
Published: November 2020

Xylitol is commonly known as one of the top platform intermediates for biomass conversion. Catalytic deoxygenation of xylitol provides an atomic and energetic efficient way to produce a variety of renewable chemicals including ethylene glycol, 1,2‐propanediol, lactic acid and 1,4‐anhydroxylitol. Despite a few initial attempts in converting xylitol into those products, improving catalyst selectivity towards C−O and C−C cleavage reactions remains a grand challenge in this area. To our best knowledge, there is lack of comprehensive review to summarize the most recent advances on catalyst design and mechanisms in deoxygenation of xylitol, offering important perspective into future development of xylitol transformation technologies. Therefore, in this mini‐review, we have critically discussed the conversion routes involved in xylitol deoxygenation over solid catalyst materials, the nanostructures of supported metal catalysts for C−H, C−C and C−O bond cleavage reactions, and mechanistic investigation for xylitol conversion. The outcome of this work provides new insights into rational design of effective deoxygenation catalyst materials for upgrading of xylitol and future process development in converting hemicellulosic biomass.
Is solar geoengineering ungovernable? A critical assessment of governance challenges identified by the Intergovernmental Panel on Climate Change
Authors: Reynolds Jesse L.
Published: November 2020

Solar radiation modification (SRM) could greatly reduce climate change and associated risks. Yet it has not been well‐received by the climate change expert community. This is evident in the authoritative reports of the Intergovernmental Panel on Climate Change (IPCC), which emphasize SRM's governance, political, social, and ethical challenges. I find seven such challenges identified in the IPCC reports: that SRM could lessen mitigation; that its termination would cause severe climatic impacts; that researching SRM would create a “slippery slope” to its inevitable and unwanted use; that decisions to use it could be contrary to democratic norms; that the public may not accept SRM; that it could be unethical; and that decisions to use SRM could be unilateral. After assessing the extent to which these challenges are supported by existing evidence, scholarly literature, and robust logic, I conclude that, for six of the seven, the IPCC's claims variously are speculative, fail to consider both advantages and disadvantages, implicitly make unreasonable negative assumptions, are contrary to existing evidence, and/or are meaninglessly vague. I suggest some reasons for the reports' failure to meet the IPCC's standards of balance, thoroughness, and accuracy, and recommend a dedicated Special Report on SRM.

This article is categorized under:

Integrated Assessment of Climate Change > Assessing Climate Change in the Context of Other Issues
Rijkswaterstaat: Guardian of the Dutch Delta
Authors: van den Brink Margo
Published: November 2020

Founded in 1798, Rijkswaterstaat, the Dutch government’s agency for infrastructural works, brought flood security, navigable waterways and highways to the Netherlands. It is an iconic institution within Dutch society, best known for its ‘battle against the water’. The Zuiderzee Works (1920–1968) and the Delta Works (1954–1997) brought worldwide acclaim. This chapter tells the story of a humble semi-military organization that developed into a formidable institution of civil engineers with a strong technocratic mission mystique. It also recounts the institutional crisis the agency experienced in the 1970s–1990s when it was too slow to adapt to major sociocultural and political changes. To ride the waves of change, it eventually developed several proactive adaptation strategies and reinvented its mission mystique in managerial terms. Adaptation to climate change now presents another key challenge, for which Rijkswaterstaat will have to develop a new ‘social license to operate’.
Médecins Sans Frontières: Guardian of Humanitarian Values
Authors: Heyse Liesbet , Korff Valeska
Published: November 2020

Médecins Sans Frontières (MSF), or Doctors without Borders, was started by a few doctors and journalists in the 1970s. Today, MSF is a humanitarian actor to be reckoned with, with its emergency medicine expertise and its unique interpretation of the neutrality and independence principles. The organization has acted unconventionally in numerous humanitarian crises and criticized peer organizations in the sector. This nonconformity has never harmed MSF; the organization is highly respected by the general public. This chapter analyzes how MSF as a principled provocateur could evolve into a public guardian of humanitarian values. We posit that MSF’s controversial acts have become an integral part of its reputation; it is expected to go against the grain. However, in order to be credible, the organization works hard to uphold its ‘volunteer and humanitarian spirit’ and strives to be an effective and professional organization.
Singapore’s Corrupt Practices Investigations Bureau: Guardian of Public Integrity
Authors: van der Wal Zeger
Published: November 2020

Singapore’s famous anti-corruption agency, the Corrupt Practices Investigations Bureau (CPIB) has been instrumental in rooting out endemic corruption in Singapore within a few decades. It has become a source of inspiration for governments in Asia and beyond. The institutionalization of the CPIB is closely intertwined with Singapore’s success as a nation. It is hard to imagine Singapore’s phenomenal economic growth would have been possible without the work of the CPIB. But how is it possible that this agency has won such extensive powers to fight corruption? This chapter shows that the agency is more than just an organization. It has become an institution. The agency has trumpeted and enforced values like fairness, meritocracy, and the rule of law, guarding them amidst turbulence for more than half a century.
Sweden’s Riksbank: Guardian of Monetary Integrity
Authors: Lindvall Johannes
Published: November 2020

The Riksbank, founded in 1668, is the world’s oldest central bank. It has played a central role in Swedish economic policymaking for centuries and enjoys a great deal of confidence among the public. This chapter explains how the Riksbank became what it is today: an independent and widely respected institution. The bank’s high status has emerged because Sweden’s political elites regard the delegation of policymaking authority to the central bank as a way of managing and containing potentially harmful political conflicts. The bank’s status also benefitted from its crisis management performance, navigating Sweden through two large-scale financial crises.
Extremal black hole scattering at $$ \mathcal{O} $$(G3): graviton dominance, eikonal exponentiation, and differential equations
Authors: Parra-Martinez Julio , Ruf Michael S. , Zeng Mao
Published: November 2020

Abstract

We use$$ \mathcal{N} $$N= 8 supergravity as a toy model for understanding the dynamics of black hole binary systems via the scattering amplitudes approach. We compute the conservative part of the classical scattering angle of two extremal (half-BPS) black holes with minimal charge misalignment at$$ \mathcal{O} $$O(G3) using the eikonal approximation and effective field theory, finding agreement between both methods. We construct the massive loop integrands by Kaluza-Klein reduction of the knownD-dimensional massless integrands. To carry out integration we formulate a novel method for calculating the post-Minkowskian expansion with exact velocity dependence, by solving velocity differential equations for the Feynman integrals subject to modified boundary conditions that isolate conservative contributions from the potential region. Motivated by a recent result for universality in massless scattering, we compare the scattering angle to the result found by Bern et. al. in Einstein gravity and find that they coincide in the high-energy limit, suggesting graviton dominance at this order.
Transverse-energy-energy correlations in deep inelastic scattering
Authors: Li Hai Tao , Vitev Ivan , Zhu Yu Jiao
Published: November 2020

Abstract

Event shape observables have been widely used for precision QCD studies at various lepton and hadron colliders. We present the most accurate calculation of the transverse-energy-energy correlation event shape variable in deep-inelastic scattering. In the framework of soft-collinear effective theory the cross section is factorized as the convolution of the hard function, beam function, jet function and soft function in the back-to-back limit. A close connection to TMD factorization is established, as the beam function when combined with part of the soft function is identical to the conventional TMD parton distribution function, and the jet function is the second moment of the TMD fragmentation function matching coefficient. We validate our framework by comparing the obtained LO and NLO leading singular distributions to the full QCD calculations in the back-to-back limit. We report the resummed transverse-energy-energy correlation distributions up to N3LL accuracy matched with the NLO cross section for the production of a lepton and two jets. Our work provides a new way to precisely study TMD physics at the future Electron-Ion Collider.
Local well-posedness of a quasi-incompressible two-phase flow
Authors: Abels Helmut , Weber Josef
Published: November 2020

We show well-posedness of a diffuse interface model for a two-phase flow of two viscous incompressible fluids with different densities locally in time. The model leads to an inhomogeneous Navier–Stokes/Cahn–Hilliard system with a solenoidal velocity field for the mixture, but a variable density of the fluid mixture in the Navier–Stokes type equation. We prove existence of strong solutions locally in time with the aid of a suitable linearization and a contraction mapping argument. To this end, we show maximal $$L^2$$

L
2

-regularity for the Stokes part of the linearized system and use maximal $$L^p$$

L
p

-regularity for the linearized Cahn–Hilliard system.
Hirntodkriterium und Organspende: aktuelle neurowissenschaftliche Perspektive
Authors: Walter Uwe
Published: November 2020

In der akademischen und öffentlichen Debatte wird der irreversible Hirnfunktionsausfall als Kriterium des Todes (Hirntodkriterium) immer wieder hinterfragt. Im vorliegenden Artikel werden 6 prototypische Thesen gegen das Hirntodkriterium diskutiert: 1) Nichtsuperiorität des Gehirns gegenüber anderen Organen, 2) Unsicherheit der Hirntoddiagnostik, 3) erhaltene Schmerzempfindung Hirntoter, 4) (spontane) sexuelle Reifung und erhaltene Reproduktionsfunktion Hirntoter, 5) Symmetrie von Hirntod und Embryonalphase, 6) Gleichsetzung des intensivmedizinisch erhaltenen Restorganismus Hirntoter mit dem lebenden Menschen.

Keine dieser Thesen hält einer kritischen Analyse stand. In Deutschland wird das Ganzhirntodkriterium angewendet. Der Hirntod geht mit dem völligen Ausfall jeglicher Empfindung, Bewusstheit, Mimik, Augen‑, Zungen- und Schlundmotorik, Willkürmotorik und Sexualfunktion einher (funktionelle „Enthauptung“). Medizinisch-technisch können andere Organe bzw. ihre Primitivsteuerung ersetzt werden, nicht aber das Gehirn. Das Gehirn, nicht der Körper, ist bestimmend für das menschliche Individuum. Die Gleichsetzung des künstlich erhaltenen Restorganismus, naturphilosophisch als lebendiges System interpretierbar, mit dem Organismus desselben lebenden Menschen wird durch die beliebige Reduzierbarkeit der Anzahl beteiligter Organead absurdumgeführt. Der irreversible Hirnfunktionsausfall führt unausweichlich zum Herzstillstand, unbehandelt innerhalb von Minuten, unter Intensivtherapie i. d. R. innerhalb von Tagen. Auch beim Embryo/Fötus führt die Fehlanlage des gesamten Gehirns zum (vorgeburtlichen) Tod. Die in Deutschland gesetzliche Richtlinie zur Hirntodfeststellung hat eine im internationalen Vergleich hohe Diagnosesicherheit, es sind damit keine bestätigten Fehldiagnosen aufgetreten.
Influence of variety and weather conditions on fatty acid composition of winter and spring Camelina sativa varieties in Poland
Authors: Kurasiak-Popowska Danuta , Graczyk Małgorzata , Przybylska-Balcerek Anna , Stuper-Szablewska Kinga
Published: November 2020

The aim of this study was to determine the influence of weather conditions over the course of 4 years (2016–2019) on the fatty acid profile of Camelina sativa. It was assumed that varieties and functional forms of plants (spring and winter genotypes) were characterized by a different fatty acid composition and that weather conditions affected the profile of fatty acids in camelina seeds. Statistical analyses were performed based on the results of chemical tests. Differences were found in the mean concentrations of C18:3n3, C18:3n6, C20:2 and C22:1 acids in all genotypes based on the Kruskal test. Two winter genotypes (Maczuga and 15/2/3) and the spring genotype UP2017/02 had the significantly highest content of C18:3n6. Genotypes CSS-CAM31, CSS-CAM30, BRSCHW 28347, CSS-CAM36 and Kirgzkij showed the highest content of C18:3n3. The lowest C18:3n3 content was found in winter genotypes: K9/1, 15/2/3, Przybrodzka (winter form) and C5. It was found that weather conditions deviating from the long-term average, both in terms of temperature and precipitation, did not affect the quantitative profile of fatty acids. Over the 4 years, no differences were observed in the fatty acid profile between the spring and winter forms. Observations made in this study allow to state that spring and winter forms of Camelina sativa retain a constant fatty acid composition regardless of changing weather conditions.
Evolution of HLA-F and its orthologues in primate species: a complex tale of conservation, diversification and inactivation
Authors: Otting N. , de Groot N. G. , Bontrop R. E.
Published: November 2020

HLA-F represents one of the nonclassical MHC class I molecules in humans. Its main characteristics involve low levels of polymorphism in combination with a restricted tissue distribution. This signals that the gene product executes a specialised function, which, however, is still poorly understood. Relatively little is known about the evolutionary equivalents of this gene in nonhuman primates, especially with regard to population data. Here we report a comparative genetic analysis of the orthologous genes of HLA-F in various great ape, Old World monkey (OWM), and New World monkey (NWM) species. HLA-F-related transcripts were found in all subjects studied. Low levels of polymorphism were encountered, although the length of the predicted gene products may vary. In most species, one or two transcripts were discovered, indicating the presence of only one active F-like gene per chromosome. An exception was provided by a New World monkey species, namely, the common marmoset. In this species, the gene has been subject to duplication, giving rise to up to six F-like transcripts per animal. In humans, great apes, and OWM, and probably the majority of the NWM species, the evolutionary equivalents of the HLA-F gene experienced purifying selection. In the marmoset, however, the gene was initially duplicated, but the expansion was subjected afterwards to various mechanisms of genetic inactivation, as evidenced by the presence of pseudogenes and an array of genetic artefacts in a section of the transcripts.
Sentiment analysis for customer relationship management: an incremental learning approach
Authors: Capuano Nicola , Greco Luca , Ritrovato Pierluigi , Vento Mario
Published: November 2020

In recent years there has been a significant rethinking of corporate management, which is increasingly based on customer orientation principles. As a matter of fact, customer relationship management processes and systems are ever more popular and crucial to facing today’s business challenges. However, the large number of available customer communication stimuli coming from different (direct and indirect) channels, require automatic language processing techniques to help filter and qualify such stimuli, determine priorities, facilitate the routing of requests and reduce the response times. In this scenario, sentiment analysis plays an important role in measuring customer satisfaction, tracking consumer opinion, interacting with consumers and building customer loyalty. The research described in this paper proposes an approach based on Hierarchical Attention Networks for detecting the sentiment polarity of customer communications. Unlike other existing approaches, after initial training, the defined model can improve over time during system operation using the feedback provided by CRM operators thanks to an integrated incremental learning mechanism. The paper also describes the developed prototype as well as the dataset used for training the model which includes over 30.000 annotated items. The results of two experiments aimed at measuring classifier performance and validating the retraining mechanism are also presented and discussed. In particular, the classifier accuracy turned out to be better than that of other algorithms for the supported languages (macro-averaged f1-score of 0.89 and 0.79 for Italian and English respectively) and the retraining mechanism was able to improve the classification accuracy on new samples without degrading the overall system performance.