bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanoparticulate formulations of radiopharmaceuticals: Strategy to improve targeting and biodistribution properties
Authors: Datta Pallab , Ray Soumendranath
Published: March 2020

Application of nanotechnology principles in drug delivery has created opportunities for treatment of several diseases. Nanotechnology offers the advantage of overcoming the adverse biopharmaceutics or pharmacokinetic properties of drug molecules, to be determined by the transport properties of the particles themselves. Through the manipulation of size, shape, charge, and type of nanoparticle delivery system, variety of distribution profiles may be obtained. However, there still exists greater need to derive and standardize definitive structure property relationships for the distribution profiles of the delivery system. When applied to radiopharmaceuticals, the delivery systems assume greater significance. For the safety and efficacy of both diagnostics and therapeutic radiopharmaceuticals, selective localization in target tissue is even more important. At the same time, the synthesis and fabrication reactions of radiolabelled nanoparticles need to be completed in much shorter time. Moreover, the extensive understanding of the several interesting optical and magnetic properties of materials in nanoscale provides for achieving multiple objectives in nuclear medicine. This review discusses the various nanoparticle systems, which are applied for radionuclides and analyses the important bottlenecks that are required to be overcome for their more widespread clinical adaptation.
Synthesis and characterization of core‐shell magnetic molecularly imprinted polymers for selective extraction of allocryptopine from the wastewater of Macleaya cordata (Willd) R. Br.
Authors: Wang Lu , Wang Yanhong , Zhou Binbin , Zhong Ming
Published: March 2020

A novel type of magnetic molecularly imprinted polymers (MMIP) as the solid‐phase extraction sorbent was prepared, which can extract effectively the allocryptopine from the waster of Macleaya cordata (Willd) R. Br. In this study, MMIP was synthesized by using Fe3O4@SiO2, 4‐vinyl‐pyridine, ethylene glycol dimethacrylate, and allocryptopine, and these ingredients worked as magnetic core, functional monomer, cross‐linker, and template, respectively. Concluded by the calculation of Gaussian 09 software, different ratio models of 4‐vinyl‐pyridine and allocryptopine were simulated, and the optimal ratio was 1:5 and the energy was −2205.34 kJ/mol. Transmission electron microscopy, vibration sample magnetometry, X‐ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used to determine the morphology and structure of MMIP. Furthermore, the results of adsorption experiments indicated that MMIP had high selectivity, excellent recyclability, and good adsorption performance (9.86 mg/g, 298 K). The adsorption process was consistent with the Langmuir adsorption isotherm (R2 > 0.98, 298 K) and pseudo‐second‐order kinetics model (R2 > 0.99, 298 K). After six times adsorption‐desorption experiments, the adsorption amount of MMIP only reduced to 8.5%. In the experiments of selective adsorption, MMIP has better adsorption properties for allocryptopine (ALL, C21H23NO5) than those having the same functional group. The limit of detection (LOD) was 0.4 μg/mL. The relative standard deviation ranged from 0.09% to 0.72%. The recovery of allocryptopine in samples ranged from 93.60% to 106.19%. In addition, the synthesized complex had a certain adsorption effect on allocryptopine separating from the wastewater of Macleaya cordata (Willd) R. Br.
Maternal health care management during the outbreak of coronavirus disease 2019
Authors: Chen Yu , Li Zhe , Zhang Yuan‐Yuan , Zhao Wei‐Hua , Yu Zhi‐Ying
Published: March 2020

Coronavirus disease 2019 (COVID‐19) is a novel type of highly contagious pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Despite the strong efforts taken to control the epidemic, hundreds of thousands of people were infected worldwide by 11 March, and the situation was characterized as a pandemic by the World Health Organization. Pregnant women are more susceptible to viral infection due to immune and anatomic alteration, though hospital visits may increase the chance of infection, the lack of medical care during pregnancy may do more harm. Hence, a well‐managed system that allows pregnant women to access maternal health care with minimum exposure risk is desired during the outbreak. Here, we present the managing processes of three pregnant women who had fever during hospitalization in the gynecology or obstetrics department, and then, we further summarize and demonstrate our maternal health care management strategies including antenatal care planning, patient triage based on the risk level, admission control, and measures counteracting emergencies and newly discovered high‐risk cases at in‐patient department. In the meantime, we will explain the alterations we have done throughout different stages of the epidemic and also review relative articles in both Chinese and English to compare our strategies with those of other areas. Although tens of COVID‐19 cases were confirmed in our hospital, no nosocomial infection has occurred and none of the pregnant women registered in our hospital was reported to be infected.
Reverse transcriptase droplet digital PCR vs reverse transcriptase quantitative real‐time PCR for serum HBV RNA quantification
Authors: Limothai Umaporn , Chuaypen Natthaya , Poovorawan Kittiyod , Chotiyaputta Watcharasak , Tanwandee Tawesak , Poovorawan Yong , Tangkijvanich Pisit
Published: March 2020

Serum hepatitis B virus (HBV) RNA is a novel marker reflecting the activity of covalently closed circular DNA. However, the methodology for detecting HBV RNA has been a technical challenge. In this study, the performance of reverse transcription droplet digital polymerase chain reaction (RT‐ddPCR) for quantifying HBV RNA was compared with that of reverse transcription quantitative real‐time PCR (RT‐qPCR) in serum samples collected from treatment‐naïve patients with different phases of chronic hepatitis B (CHB). A total of 417 serum samples, including 136 HBeAg‐positive CHB and 281 HBeAg‐negative CHB were examined. HBV RNA levels measured by RT‐ddPCR and RT‐qPCR showed a high degree of linearity and quantitative correlation. The limit of detections of RT‐ddPCR and RT‐qPCR assays were 102 and 103 copies/mL, respectively. Our results also demonstrated that RT‐ddPCR was superior to RT‐qPCR in terms of its consistency for quantifying HBV RNA across all concentrations. In the HBeAg‐positive group, serum HBV RNA levels based on RT‐ddPCR were moderately correlated with HBV DNA (r = 0.591, P < .001) and HBsAg (r = 0.502, P < .001). Among patients with HBeAg‐negative CHB, serum HBV RNA levels were moderately correlated with HBV DNA (r = 0.603, P < .001) but had weak correlation with HBsAg (r = 0.203, P = .001). In summary, RT‐ddPCR could enhance the sensitivity of serum HBV RNA detection, particularly among the HBeAg‐negative group with low viral loads. Thus, RT‐ddPCR could serve as an optimal method for HBV RNA quantification in clinical practice.
Collaborating for public access to scholarly publications: A case study of the partnership between the US Department of Energy and CHORUS
Authors: Dylla H. Frederick , Salmon Jeffrey
Published: March 2020

Key points

The success of the CHORUS and DOE relationship is the result of nearly two decades of interactions between the DOE and a group of scientific publishers.

The relationship between CHORUS and the US federal agencies required understanding of different motivations, operations, and philosophies.

Although achieving public access was simple in principle, it required considerable effort to develop systems that satisfied all parties.

Publishers had been working with federal agencies to achieve open access before the 2013 White House Office of Science and Technology Policy, but this helped to create a path for a more fruitful relationship.
Acetylated cellulose nanostructures as reinforcement materials for PBAT nanocomposites
Authors: Barbosa Rennan F. S. , Souza Alana G. , Rosa Derval S.
Published: March 2020

Acetylated‐cellulose nanostructures (CNS) were used as reinforcing agent to develop poly(butylene adipate‐co‐terephthalate)—PBAT—nanocomposites with 1, 3, 5, and 10 wt% of modified and nonmodified nanoparticles through solvent casting. This study explains the interactions between the reactive groups CNS and PBAT interact and the influence of this interaction in the mechanical and thermal properties of the composites. The nonmodified CNS showed a noncontinuous increase in the PBAT stiffness, due to the low interaction between the reinforcement and the matrix and low CNS dispersion. The best results were obtained to acetylated CNS due to the intermolecular interactions between the acetyl groups and the polymer chains. Probably the acetyl groups interfered in the atomic vibration relative to the functional groups of the matrix, which is indicative of the interaction and enhancement of the internal cohesion of the components.
Difference score reliabilities within the RIAS‐2 and WISC‐V
Authors: Farmer Ryan L. , Kim Samuel Y.
Published: March 2020

Many prominent intelligence tests (e.g., Wechsler Intelligence Scale for Children, Fifth Edition [WISC‐V] and Reynolds Intellectual Abilities Scale, Second Edition [RIAS‐2]) offer methods for computing subtest‐ and composite‐level difference scores. This study uses data provided in the technical manual of the WISC‐V and RIAS‐2 to calculate reliability coefficients for difference scores. Subtest‐level difference score reliabilities range from 0.59 to 0.99 for the RIAS‐2 and from 0.53 to 0.87 for the WISC‐V. Composite‐level difference score reliabilities generally range from 0.23 to 0.95 for the RIAS‐2 and from 0.36 to 0.87 for the WISC‐V. Emphasis is placed on comparisons recommended by test publishers and a discussion of minimum requirements for interpretation of differences scores is provided.
Gas Transport in the Insensitive High Explosive PBX 9502
Authors: Englert‐Erickson Michael A. , Holmes Matthew D. , Parker Gary R. , Schmidt Chad C. , Meyer Brad A.
Published: March 2020

Small‐scale laboratory experiments were performed to analyze gas transport mechanics in PBX 9502, an insensitive high explosive (IHE) composition. Two independent investigations are reported here. First, gas permeametry and dynamic pycnometry techniques were used to measure the molecular flow (Knudsen) coefficient and the internally interconnected void fraction of pristine and thermally damaged samples in two uniaxial pressing orientations. The permeability of PBX 9502 was found to be unmeasurably low (of the same order of magnitude as PTFE) with gas transport being diffusion‐dominated. Secondly, a pressure vessel experiment was developed to measure quasi‐static and dynamic gas generation as the explosive was heated to self‐ignition (cookoff). The gas generation results and the permeability/diffusivity findings provide evidence that PBX 9502 remains impermeable until seconds prior to self‐ignition. At ignition, internal void‐pressure drives macro‐scale cracking and the sample becomes uniformly incorporated in the following deconsolidating deflagration. These results are discussed within the context of previous observations of pressure‐dependent cookoff behavior of PBX 9502 and provide a more complete description of thermal damage evolution in this explosive composition.
Comparison of gaseous ubiquitin ion structures obtained from a solid and solution matrix using ion mobility spectrometry/mass spectrometry
Authors: Inutan Ellen D. , Jarois Dean R. , Lietz Christopher B. , El‐Baba Tarick J. , Elia Efstathios A. , Karki Santosh , Sampat Andjoe A.S. , Foley Casey D. , Clemmer David E. , Trimpin Sarah
Published: March 2020

Rationale

Examining surface protein conformations, and especially achieving this with spatial resolution, is an important goal. The recently discovered ionization processes offer spatial‐resolution measurements similar to matrix‐assisted laser desorption/ionization (MALDI) and produce charge states similar to electrospray ionization (ESI) extending higher‐mass protein applications directly from surfaces on high‐performance mass spectrometers. Studying a well‐interrogated protein by ion mobility spectrometry‐mass spectrometry (IMS‐MS) to access effects on structures using a solid vs. solvent matrix may provide insights.

Methods

Ubiquitin was studied by IMS‐MS using new ionization processes with commercial and homebuilt ion sources and instruments (Waters SYNAPT G2(S)) and homebuilt 2 m drift‐tube instrument; MS™ sources). Mass‐to‐charge and drift‐time (td)‐measurements are compared for ubiquitin ions obtained by inlet and vacuum ionization using laserspray ionization (LSI), matrix‐ (MAI) and solvent‐assisted ionization (SAI), respectively, and compared with those from ESI under conditions that are most comparable.

Results

Using the same solution conditions with SYNAPT G2(S) instruments, td‐distributions of various ubiquitin charge states from MAI, LSI, and SAI are similar to those from ESI using a variety of solvents, matrices, extraction voltages, a laser, and temperature only, showing subtle differences in more compact features within the elongated distribution of structures. However, on a homebuilt drift‐tube instrument, within the elongated distribution of structures, both similar and different td‐distributions are observed for ubiquitin ions obtained by MAI and ESI. MAI‐generated ions are frequently narrower in their td‐distributions.

Conclusions

Direct comparisons between ESI and the new ionization methods operational directly from surfaces suggest that the protein in its solution structure prior to exposure to the ionization event is either captured (frozen out) at the time of crystallization, or that the protein in the solid matrix is associated with sufficient solvent to maintain the solution structure, or, alternatively, that the observed structures are those related to what occurs in the gas phase with ESI‐ or MAI‐generated ions and not with the solution structures.
Gas‐phase study of the stability of α‐substituted cyclic amino nitriles under electron ionization and electrospray ionization and fragmentation peculiarities of cyclic ketimines
Authors: Sosnova Anna A. , Mazur Dmitrii M. , Lebedev Albert T.
Published: March 2020

Rationale

α‐Substituted cyclic amino nitriles show different reactivity and stability in solution depending on their ring size. Mass‐spectrometric modeling of the reactions, which normally take place in solution, may shed light on the nature of the studied compounds and explain some observations.

Methods

The stability of the nitriles in an acidic solution was studied by adding glacial acetic acid. Gas‐phase modelling was conducted by gas chromatography/mass spectrometry (GC/MS) with electron ionization mass spectrometry and direct inlet electrospray ionization. QqQ and Orbitrap analyzers were used to carry out tandem mass spectrometry (MS/MS) experiments.

Results

The obtained data show that the elimination of HCN from α‐substituted cyclic amino nitriles occurs in the same way for an acidic solution, thermolysis and electrospray ionization. According to GC, the most stable were N‐formylated nitriles compared with N‐benzylated or N‐unsubstituted ones. Electrospray ionization demonstrated its advantages for the routine identification of cyclic amino nitriles due to milder conditions than in electron ionization. Fragmentations of cyclic ketimines, formed from N‐unsubstituted amino nitriles, are discussed in particular.

Conclusions

Similarities in the behavior of the α‐substituted cyclic amino nitriles under electron ionization, electrospray ionization, thermolysis and reaction in solution under acidic catalysis were discovered and confirmed by MS/MS experiments. Fragmentation schemes of the studied nitriles and corresponding imines are proposed.
A rapid sample preparation method for the analysis of stable isotope ratios of beef samples from different countries
Authors: Zhao Shanshan , Zhang Hongbo , Zhang Bin , Xu Zhenzhen , Chen Ailiang , Zhao Yan
Published: March 2020

Rationale

The use of multi‐isotopic analyses to trace beef is gaining wider acceptance, but no uniform standard for the pretreatment method is available for the determination of stable isotope ratios. Drying and defatting of meat samples are usually applied. Thus, a rapid sample preparation procedure is required to provide a reference for the study of beef using stable isotope methods.

Methods

Student's t‐test (T‐test) was used to determine significant differences between the δ13C and δ15N values in traditional and rapid beef sample preparation methods. The δ13C, δ15N, δ2H, and δ18O values of beef samples from six countries were assayed using elemental analyzer–isotope ratio mass spectrometry. Stable isotope data were subjected to principal component analysis, discriminant analysis, and partial least‐squares discriminant analysis (PLS‐DA).

Results

There was no significant difference (P > 0.05) between the δ13C and δ15N values of the two preparation approaches. A classification of satisfactory was obtained with the original‐validation rate of 96.6% and the cross‐validation rate of 95.9%. The PLS‐DA model was correctly validated to differentiate beef samples from six countries.

Conclusions

We describe a rapid sample preparation method for beef samples. A model combining stable isotope data and chemometric methods correctly assigned the origin of beef samples from different countries. The results demonstrated the successful utilization of rapid pretreatment methods to prepare beef samples when using multiple stable isotope analyses to trace beef samples from different countries.
When do return migrants become entrepreneurs? The role of global social networks and institutional distance
Authors: Wang Dan J.
Published: March 2020

Research Summary

Does embeddedness in global social networks elevate or diminish individuals' propensity to found new ventures? I analyze entrepreneurial entry among a large, cross‐country sample of skilled return migrants, all of whom had worked abroad in the United States before returning to 98 different home countries. My findings reveal that maintaining stronger cross‐border social ties—that is, relationships to former colleagues abroad—leads returnees to be more likely to found new ventures in their homelands. However, the positive effects of cross‐border social ties diminish with greater institutional distance between the returnee's home country and the United States. The findings have implications for research at the intersection of social networks, international migration, and entrepreneurship.

Managerial Summary

When it comes to founding a venture, social networks are often critical in helping prospective entrepreneurs identify new market opportunities and resources. Which types of networks are most beneficial in helping people become entrepreneurs, however, still remains a question. This paper asks whether having social connections to individuals across countries makes one more likely to become an entrepreneur, and if so why? Studying skilled return migrants, I find that returnees who maintain stronger social ties to those they met while working abroad are more likely to start companies, but only if there is sufficient similarity between the market environments of the returnee's home country and the country where the returnee worked abroad.
Metal‐Containing Polydopamine Nanomaterials: Catalysis, Energy, and Theranostics
Authors: Wang Zhao , Zou Yuan , Li Yiwen , Cheng Yiyun
Published: March 2020

Polydopamine (PDA) is a major type of artificial melanin material with many interesting properties such as antioxidant activity, free‐radical scavenging, high photothermal conversion efficiency, and strong metal‐ion chelation. The high affinity of PDA to a wide range of metals/metal ions has offered a new class of functional metal‐containing polydopamine (MPDA) nanomaterials with promising functions and extensive applications. Understanding and controlling the metal coordination environment is vital to achieve desirable functions for which such materials can be exploited. MPDA nanomaterials with metal/metal ions as the active functions are reviewed, including their synthesis and metal coordination environment and their applications in catalysis, batteries, solar cells, capacitors, medical imaging, cancer therapy, antifouling, and antibacterial coating. The current trends, limitations, and future directions of this area are also explored.
Seismic performance assessment of two‐storey precast reinforced concrete building
Authors: Chourasia Ajay , Kajale Yogesh , Singhal Shubham , Parashar Jalaj
Published: March 2020

In precast construction, standardized concrete elements are manufactured in a controlled environment followed by onsite installations. One such precast system is 3S building system (Strength, Safety, and Speed), which consists of RCC hollow columns with notches; RCC solid beams (“T” shape/“L” shape/Square Shape), RCC Stair flights, RCC shear walls, and Autoclave Aerated Concrete (AAC) or RCC precast slab. The current study focuses on seismic performance of this system, where a full‐scale two storey, “3S” precast RC building, was subjected to quasi‐static lateral loading. The experimental results show that the structure responded within elastic range at Life Safety (LS) performance level with minimal damage to the joints. The results are further compared to an analytical model in SAP2000 subjected to pushover analysis. Both the experimental and analytical results were found to be in agreement. Therefore, it is inferred that the 3S building system can perform satisfactorily under seismic loads.
Learning and Teaching Through the Online Environmental Justice Atlas: From Empowering Activists to Motivating Students
Authors: Walter Mariana , Weber Lena , Temper Leah
Published: March 2020

The chapter analyzes how the Environmental Justice Atlas (EJAtlas.org), an online interactive platform developed to visualize and study struggles against environmental injustices worldwide, is used in higher education curricula to teach environmental justice and sustainability themes.
Sustainability Education Assessments in Teacher Education: Addressing “Wicked Problems” in a Postmodern World
Authors: Wright Mary F. , Monsour Florence A.
Published: March 2020

This chapter describes an evolving narrative inquiry into the use of formative sustainability assessments in teacher education for elementary and secondary level education. Framed within a postmodern approach to education, we describe the efficacy of using experiential, performative, discursive, graphic, and reflective assessments to bolster critical and creative holistic understandings.
Public participation, engagement, and climate change adaptation: A review of the research literature
Authors: Hügel Stephan , Davies Anna R.
Published: March 2020

There is a clear need for a state‐of‐the‐art review of how public participation in climate change adaptation is being considered in research across academic communities: The Rio Declaration developed in 1992 at the UN Conference on Environment and Development (UNCED) included explicit goals of citizen participation and engagement in climate actions (Principle 10). Nation states were given special responsibility to facilitate these by ensuring access to information and opportunities to participate in decision‐making processes. Since then the need for public participation has featured prominently in calls to climate action. Using text analysis to produce a corpus of abstracts drawn from Web of Science, a review of literature incorporating public participation and citizen engagement in climate change adaptation since 1992 reveals lexical, temporal, and spatial distribution dynamics of research on the topic. An exponential rise in research effort since the year 2000 is demonstrated, with the focus of research action on three substantial themes—risk, flood risk, and risk assessment, perception, and communication. These are critically reviewed and three substantive issues are considered: the paradox of participation, the challenge of governance transformation, and the need to incorporate psycho‐social and behavioral adaptation to climate change in policy processes. Gaps in current research include a lack of common understanding of public participation for climate adaptation across disciplines; incomplete articulation of processes involving public participation and citizen engagement; and a paucity of empirical research examining how understanding and usage of influential concepts of risk, vulnerability and adaptive capacity varies among different disciplines and stakeholders. Finally, a provisional research agenda for attending to these gaps is described.

This article is categorized under:

Vulnerability and Adaptation to Climate Change > Institutions for Adaptation

Policy and Governance > Governing Climate Change in Communities, Cities, and Regions
Clustering of multivariate geostatistical data
Authors: Fouedjio Francky
Published: March 2020

Multivariate data indexed by spatial coordinates have become increasingly popular in many geoscientific fields. This type of data imposes new analysis challenges, including the clustering of irregularly sampled data locations into spatially contiguous clusters given a set of regionalized variables. Clusters of data locations created through general‐purpose clustering techniques turn out to show poor spatial contiguity, a characteristic obviously inconvenient for many geoscience applications. This article reviews clustering methods designed explicitly for multivariate geostatistical data in which spatial dependency plays an important role. These clustering techniques are modifications of general‐purpose clustering methods. They provide spatially contiguous clusters by accounting for the spatial dependency of data locations.

This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Clustering and Classification

Data: Types and Structure > Image and Spatial Data
Heterogeneity of Market Structures in the Iranian Model of Kidney Transplantation
Authors: Feizi Mehdi , Moeindarbari Tannaz
Published: March 2020

The Iranian model of kidney transplantation (IMKT) is an example of a legal system of compensated, living, and unrelated renal donation. This study demonstrates its heterogeneity regarding prerequisites, restrictions, and policies for matching donors and recipients with an emphasis on the case of Mashhad, in which the Iranian Kidney Foundation (IKF) received criticism about the kidney market. The IKF in Mashhad strives to prevent the poor from imprudently selling their own kidneys by informing them about the consequences of a kidney transplant, resolving their financial needs, and imposing several legal obstacles before a transplant is allowed. We show that the IMKT does not fully eliminate excess demand for kidneys, although it significantly decreases demand so that Iran has the shortest waiting list in the world. Nevertheless, the relative number of kidney transplants, especially from deceased donors, are higher in Mashhad compared to the average of other centers in Iran, as almost forty percent of renal patients on the active waiting list get a kidney each year.
Gendered Patterns of Drug Use on a University Campus in the United States
Authors: De Soto William , Tajalli Hassan
Published: March 2020

Substance use patterns are important to understand because they can have a variety of effects on those who engage in them. Some of these consequences can be harmful. This is especially true for young adults in college settings who are making the transition to adulthood. While the issue of substance use looms large in the research literature on college students, less attention had been focused exclusively on women in this important setting. This paper attempts to address this limitation in existing research by assessing the utility of two theories of human behavior for explaining substance use among female college students (i) Social Learning Theory and (ii) General Strain Theory. There does appear to be support for learning theory but not for strain theory.
Synthesis, X‐ray Structures, and Photoluminescence of the Octahedral Cu4I4 Cluster with Bulky Bidentate Bis(phosphanyl)amine Ligand
Authors: Al‐Masri Harbi Tomah , Almejled Akram Ali
Published: March 2020

The reaction of C10H7‐1‐N(PPh2)2 (1) with two equivalents of CuI in acetonitrile resulted in the formation of octahedron Cu4I4[1]2 complex (2). The crystal structure of 2 showed it adopted a rare octahedral arrangement. The rectangular Cu4 plane is μ4‐capped by two of the iodides and is placed in axial positions above and below the Cu4‐plane form an octahedron, whereas the other two iodides are bonded to two copper atoms in a μ2‐fashion. The luminescence of complex 2 arises from a triplet halide‐to‐ligand charge transfer (3XLCT) excited state and 3CC (Cu4I4 cluster‐centered) excited state are not involved in the luminescence by the rigid bidentate ligand 1 in spite of the short CuI–CuI bond length. Complex 2 was identified and characterized by multinuclear NMR (1H, 13C, 31P NMR) and IR spectroscopy. Crystal structure determinations of 1 and 2 were carried out.
On anomalous conformal Ward identities for Wilson loops on polygon-like contours with circular edges
Authors: Dorn Harald
Published: March 2020

Abstract

We derive the anomalous conformal Ward identities for $$ \mathcal{N} $$
N
= 4 SYM Wilson loops on polygon-like contours with edges formed by circular arcs. With a suitable choice of parameterisation they are very similarly to those for local correlation functions. Their solutions have a conformally covariant factor depending on the distances of the corners times a conformally invariant remainder factor depending, besides on cross ratios of the corners, on the cusp angles and angles parameterising the torsion of the contours.
Topological entanglement entropy in d-dimensions for Abelian higher gauge theories
Authors: Ibieta-Jimenez J.P. , Petrucci M. , Xavier L.N. Queiroz , Teotonio-Sobrinho P.
Published: March 2020

Abstract

We compute the topological entanglement entropy for a large set of lattice models in d-dimensions. It is well known that many such quantum systems can be constructed out of lattice gauge models. For dimensionality higher than two, there are generalizations going beyond gauge theories, which are called higher gauge theories and rely on higher-order generalizations of groups. Our main concern is a large class of d-dimensional quantum systems derived from Abelian higher gauge theories. In this paper, we derive a general formula for the bipartition entanglement entropy for this class of models, and from it we extract both the area law and the sub-leading terms, which explicitly depend on the topology of the entangling surface. We show that the entanglement entropy SA in a sub-region A is proportional to log $$ \left({GSD}_{\tilde{A}}\right) $$

GSD

A
˜

, where $$ {GSD}_{\tilde{A}} $$

GSD

A
˜

is the ground state degeneracy of a particular restriction of the full model to A. The quantity $$ {GSD}_{\tilde{A}} $$

GSD

A
˜

can be further divided into a contribution that scales with the size of the boundary ∂A and a term which depends on the topology of ∂A. There is also a topological contribution coming from A itself, that may be non-zero when A has a non-trivial homology. We present some examples and discuss how the topology of A affects the topological entropy. Our formalism allows us to do most of the calculation for arbitrary dimension d. The result is in agreement with entanglement calculations for known topological models.
Fibration structure in toric hypersurface Calabi-Yau threefolds
Authors: Huang Yu-Chien , Taylor Washington
Published: March 2020

Abstract

We find through a systematic analysis that all but 29,223 of the 473.8 million 4D reflexive polytopes found by Kreuzer and Skarke have a 2D reflexive subpolytope. Such a subpolytope is generally associated with the presence of an elliptic or genus one fibration in the corresponding birational equivalence class of Calabi-Yau threefolds. This extends the growing body of evidence that most Calabi-Yau threefolds have an elliptically fibered phase.
Carotid Stenting as Definitive Treatment for Free Floating Thrombus—Review of 7 Cases
Authors: Bhogal P. , AlMatter M. , Aguilar Pérez M. , Bäzner H. , Henkes H. , Hellstern V.
Published: March 2020

Background and Purpose

Free floating thrombus (FFT) is a rare condition. The optimal treatment strategy is yet to be determined although medical management with anticoagulation is the mainstay. This article reports experience of treating FFT with carotid stenting.

Methods

A retrospective analysis of a prospectively maintained database was performed to identify all patients with FFT treated with carotid stenting. For each patient the demographic data, clinical presentation, location of the thrombus, type of stent and use of adjunctive devices, e.g. balloon guide catheters, clinical and radiological follow-up information as well as complications were recorded.

Results

A total of 7 patients, 4 female, with mean age of 55.6 ± 14.5 years were identified. The median National Institutes of Health Stroke Scale (NIHSS) was 7 (range 0–13) at presentation. Free floating thrombus was seen on the left in the majority of cases (n = 6, 85.7%). None of the patients had intracranial large vessel occlusion. The FFT was located in the CCA in 2 cases (28.6%) and the proximal ICA in the remaining 5 cases (71.4%). The Wallstent was used in 5 patients and a cGuard stent used in 2 patients. In 1 patient 2 overlapping stents were used but a single stent was used in the remaining patients. In 6 cases a distal filter wire was used and in 2 cases a balloon guide catheter was used as embolic protection. There were no intraoperative complications and no cases of distal clot migration or intracranial large vessel occlusion during the procedure. At last follow-up (n = 7) 6 patients were recorded as modified Rankin Scale (mRS) ≤2 and 1 patient was mRS 3.

Conclusion

Free floating thrombus of the carotid arteries can be managed with stenting.
Dopaminergic contributions to behavioral control under threat of punishment in rats
Authors: Verharen Jeroen P. H. , Luijendijk Mieneke C. M. , Vanderschuren Louk J. M. J. , Adan Roger A. H.
Published: March 2020

Rationale

Excessive intake of rewards, such as food and drugs, often has explicit negative consequences, including the development of obesity and addiction, respectively. Thus, choosing not to pursue reward is the result of a cost/benefit decision, proper execution of which requires inhibition of behavior. An extensive body of preclinical and clinical evidence implicates dopamine in certain forms of inhibition of behavior, but it is not fully known how it contributes to behavioral inhibition under threat of explicit punishment.

Objectives

To assess the involvement of midbrain dopamine neurons and their corticostriatal output regions, the ventral striatum and prefrontal cortex, in control over behavior under threat of explicit (foot shock) punishment in rats.

Methods

We used a recently developed behavioral inhibition task, which assesses the ability of rats to exert behavioral restraint at the mere sight of food reward, under threat of foot shock punishment. Using in vivo fiber photometry, chemogenetics, c-Fos immunohistochemistry, and behavioral pharmacology, we investigated how dopamine neurons in the ventral tegmental area, as well as its output areas, the ventral striatum and prefrontal cortex, contribute to behavior in this task.

Results

Using this multidisciplinary approach, we found little evidence for a direct involvement of ascending midbrain dopamine neurons in inhibitory control over behavior under threat of punishment. For example, photometry recordings suggested that VTA DA neurons do not directly govern control over behavior in the task, as no differences were observed in neuronal population activity during successful versus unsuccessful behavioral control. In addition, chemogenetic and pharmacological manipulations of the mesocorticolimbic DA system had little or no effect on the animals’ ability to exert inhibitory control over behavior. Rather, the dopamine system appeared to have a role in the motivational components of reward pursuit.

Conclusions

Together, our data provide insight into the mesocorticolimbic mechanisms behind motivated behaviors by showing a modulatory role of dopamine in the expression of cost/benefit decisions. In contrast to our expectations, dopamine did not appear to directly mediate the type of behavioral control that is tested in our task.
MRI of female genital tract congenital anomalies: European Society of Urogenital Radiology (ESUR) guidelines
Authors: Maciel Cristina , Bharwani Nishat , Kubik-Huch Rahel A. , Manganaro Lucia , Otero-Garcia Milagros , Nougaret Stephanie , Alt Celine D. , Cunha Teresa Margarida , Forstner Rosemarie
Published: March 2020

Objective

To develop imaging guidelines for the MR work-up of female genital tract congenital anomalies (FGTCA).

Methods

These guidelines were prepared based on a questionnaire sent to all members of the European Society of Urogenital Radiology (ESUR) Female Pelvic Imaging Working Group (FPI-WG), critical review of the literature and expert consensus decision.

Results

The returned questionnaires from 17 different institutions have shown reasonable homogeneity of practice. Recommendations with focus on patient preparation and MR protocol are proposed, as these are key to optimised examinations. Details on MR sequences and planning of uterus-orientated sequences are provided.

Conclusions

The multiplanar capabilities and soft tissue resolution of MRI provide superb characterisation of the wide spectrum of findings in FGTCA. A standardised imaging protocol and method of reporting ensures that the salient features are recognised, contributing to a correct diagnosis and classification of FGTCA, associated anomalies and complications. These imaging guidelines are based on current practice among expert radiologists in the field and incorporate up to date information regarding MR protocols and essentials of recently published classification systems.

Key Points

• MRI allows comprehensive evaluation of female genital tract congenital anomalies, in a single examination.

• A dedicated MRI protocol comprises uterus-orientated sequences and vaginal and renal evaluation.

• Integration of classification systems and structured reporting helps in successful communication of the imaging findings.
Typisierung von Floaterpatienten
Authors: Hahn Ursula , Baulig C. , Tulka S. , Ludwig K.
Published: March 2020

Subjektive Beeinträchtigung von Floaterpatienten entzieht sich ophthalmologischen Messverfahren. Im Sinne einer Typisierung von Floaterpatienten sollen patientenbezogene Merkmale identifiziert werden, die mit höherer Beeinträchtigung assoziiert sind. Ein Datensatz einer prospektiven, multizentrischen, einarmigen Primärstudie zu 64 Floaterpatienten, die sich einer Vitrektomie unterzogen haben, umfasst neben patientenbezogenen Merkmalen Angaben zu subjektiver prä- und postoperativer (3 Monate nach Vitrektomie) Beeinträchtigung, die mit einem spezifischen Floaterfragebogen erhoben und zu relativen Beeinträchtigungsindizes (RBI) verdichtet wurden. Mediane der RBI wurden zu den Ausprägungen soziodemografischer und ophthalmologischer Parameter sowie der untersucherseitigen Beurteilung des Floaterausmaßes auf dem Studienauge und am zweiten Auge berechnet und auf Signifikanz getestet. Höhere präoperative RBI waren mit Berufstätigkeit, niedrigerem Alter, mit den präoperativen Befunden reduzierte Sehschärfe, Veränderungen der Netzhaut und höhere Fehlsichtigkeit sowie dem Vorliegen von Floatern am zweiten Auge verbunden. Höhere postoperative RBI lagen bei Indikation zur Kataraktoperation und niedrigerem Alter vor. Die RBI-Unterschiede waren nur punktuell signifikant. Die Behandlereinschätzung zum Ausmaß von Floatern einerseits und nach RBI andererseits waren nur für ansonsten augengesunde Patientenpopulationen signifikant korreliert. Die Primärstudie berichtete hohe präoperative Beeinträchtigung und erheblichen Rückgang der RBI nach Vitrektomie für nahezu alle Patienten. Die aktuelle Studie zeigt, dass einzelne patientenbezogene Merkmale tendenziell mit höherer präoperativer Beeinträchtigung und größerem Nutzen einer Vitrektomie verbunden sind.
Novel test section for homogeneous nucleation studies in a pulse expansion wave tube: experimental verification and gasdynamic 2D numerical model
Authors: Campagna M. M. , van Dongen M. E. H. , Smeulders D. M. J.
Published: March 2020

A novel design of a pulse expansion wave tube (PEWT) for the study of homogeneous nucleation in mixtures of vapours and gases is presented. The main difference with the previous design consists in a test section with flat walls, which avoid that optical windows and pressure transducers do affect the flow field locally. Additionally, the test section length is reduced by a factor two. The performance of the wave tube is investigated both experimentally and numerically. The thermal insulation of the piezoelectric pressure sensor is proved to be beneficial for accurate measurements. The smallest thickness possible of the diaphragm, initially separating the high- and low-pressure sections of the PEWT, is also shown to be crucial. The flow phenomena are simulated with a 2D numerical model. It is shown to correctly predict the gasdynamic features of the PEWT and the effects of the diaphragm opening process. Nucleation rates for water in helium are determined as a function of supersaturation for two different pressure conditions, 1 MPa and 0.1 MPa, at a temperature of 240 K. The good agreement with results from previous experiments shows that the geometrical mismatch of optical windows and pressure transducers in the original wave tube did not affect the nucleation rates significantly and that both the original and the new wave tube produce reliable measurement data.

Graphic abstract
Effects of syntaxins 2, 3, and 4 on rat and human epithelial sodium channel (ENaC) in Xenopus laevis oocytes
Authors: Rauh Robert , Frost Fabian , Korbmacher Christoph
Published: March 2020

Syntaxins are SNARE proteins and may play a role in epithelial sodium channel (ENaC) trafficking. The aim of the present study was to investigate the effects of syntaxin 2 (STX2), syntaxin 3 (STX3), and syntaxin 4 (STX4) on rat (rENaC) and human ENaC (hENaC). Co-expression of rENaC and STX3 or STX4 in Xenopus laevis oocytes increased amiloride-sensitive whole-cell currents (ΔIami) on average by 50% and 135%, respectively, compared to oocytes expressing rENaC alone. In contrast, STX2 had no significant effect on rENaC. Similar to its effect on rENaC, STX3 stimulated hENaC by 48%. In contrast, STX2 and STX4 inhibited hENaC by 51% and 44%, respectively. Using rENaC carrying a FLAG tag in the extracellular loop of the β-subunit, we demonstrated that the stimulatory effects of STX3 and STX4 on ΔIami were associated with an increased expression of the channel at the cell surface. Co-expression of STX3 or STX4 did not significantly alter the degree of proteolytic channel activation by chymotrypsin. STX3 had no effect on the inhibition of rENaC by brefeldin A, and the stimulatory effect of STX3 was preserved in the presence of dominant negative Rab11. This indicates that the stimulatory effect of STX3 is not mediated by inhibiting channel retrieval or by stimulating fusion of recycling endosomes. Our results suggest that the effects of syntaxins on ENaC are isoform and species dependent. Furthermore, our results demonstrate that STX3 increases ENaC expression at the cell surface, probably by enhancing insertion of vesicles carrying newly synthesized channels.
Virus-specific T cells in pediatric renal transplantation
Authors: Ahlenstiel-Grunow Thurid , Pape Lars
Published: March 2020

After pediatric kidney transplantation, immunosuppressive therapy causes an increased risk of severe viral complications, especially from cytomegalovirus (CMV), BK polyomavirus (BKPyV) or Epstein-Barr virus (EBV), and less frequent from adenovirus (ADV). However, suitable predictive markers for the individual outcome of viral infections are missing and the therapeutic management remains a challenge to the success of pediatric kidney transplantation. Virus-specific T cells are known for controlling viral replication and there is growing evidence that virus-specific T cells may serve as a prognostic marker to identify patients at risk for viral complications. This review provides an overview of the usability of virus-specific T cells for improving diagnostic and therapeutic management of viral infections with reference to the necessity of antiviral prophylaxis, timing of pre-emptive therapy, and dosing of immunosuppressive medication after pediatric kidney transplantation. Several studies demonstrated that high levels of virus-specific T cells are associated with decrease of virus load and favorable outcome, whereas lack of virus-specific T cells coincided with virus-induced complications. Accordingly, the additional monitoring of virus-specific T cells aims to personalize the management of antiviral therapy, identify overimmunosuppression, and avoid unnecessary therapeutic interventions. Prospective randomized trials in pediatric kidney recipients comparing standard antiviral and immunosuppressive regimens with T cell-guided therapeutic interventions are needed, before monitoring of virus-specific T cells is implemented in the routine care of pediatric kidney graft recipients.
Trekstock RENEW: evaluation of a 12-week exercise referral programme for young adult cancer survivors delivered by a cancer charity
Authors: Pugh G. , Below N. , Fisher A. , Reynolds J. , Epstone S.
Published: March 2020

Purpose

To evaluate the uptake and effect of RENEW, a 12-week exercise referral programme for young adult cancer survivors delivered by Trekstock, a UK-based cancer charity.

Methods

The RENEW programme provides one-to-one individually tailored support from a level-4 cancer-rehabilitation-qualified gym instructor, free gym membership and access to information resources online. Objective and self-report data on cardiorespiratory function, strength, body composition, fatigue, sleep quality and general health-related quality of life (HRQoL) was collected from participants before the programme (week 0), immediately after (week 12) and 1 month later (week 16).

Results

Forty-eight young adults (83% female; mean age, 29 years) with a history of cancer took part within the 12-week programme and completed the evaluation measures. Physical activity (PA) levels significantly increased following the programme and remained raised at follow-up. Improvements in physical function were significant: peak expiratory flow (mean change, 30.96, p = 0.003), sit-and-reach test (mean change, 6.55 ± 4.54, p < 0.0001), and 6-mine-walk test (mean change, 0.12 ± 0.04, p < 0.0001). No significant changes in BMI, weight or muscle mass were observed. Improvements in fatigue, sleep and HRQoL were observed across the programme and at follow-up (mean change, weeks 0–16; 8.04 ± 1.49 p < 0.01; 1.05 ± 0.49 p < 0.05; and − 0.9 ± 0.46 p = 0.051, respectively). Changes in self-efficacy to exercise and motivations to exercise were not observed at 12 weeks or at follow-up.

Conclusions

Results suggest that the RENEW exercise referral programme has a positive impact upon some domains of physical function and well-being among young adult cancer survivors.

Implication for cancer survivors

Exercise referral programmes delivered by charity organisations are one means by which PA behaviour change support may be widely disseminated to young adult cancer survivors. Health professionals and charitable bodies specialising in the care of young adults with cancer should look to address factors which prevent engagement and uptake of ‘real-world’ PA interventions such as the RENEW programme.