bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Analysis of Position–Effect Variegation Mutations in Drosophila melanogaster Delineates the Targets of Modifiers
Authors: Sass Georgette L , Henikoff Steven
Published: July 2021

In Drosophila melanogaster, heterochromatin-induced silencing or position–effect variegation (PEV) of a reporter gene has provided insights into the properties of heterochromatin. Class I modifiers suppress PEV, and class II modifiers enhance PEV when the modifier gene is present in fewer than two doses. We have examined the effects of both class I and class II modifiers on four PEV mutations. These mutations include the inversions In(1)wm4 and In(2R)bwVDe2, which are classical chromosomal rearrangements that typify PEV mutations. The other mutations are a derivative of brownDominant, in which brown+ reporters are inactivated by a large block of heterochromatin, and a P[white+] transposon insertion associated with second chromosome heterochromatin. In general, we find that class I modifiers affect both classical and nonclassical PEV mutations, whereas class II modifiers affect only classical PEV mutations. We suggest that class II modifiers affect chromatin architecture in the vicinity of reporter genes, and only class I modifiers identify proteins that are potentially involved in heterochromatin formation or maintenance. In addition, our observations support a model in which there are different constraints on the process of heterochromatin-induced silencing in classical vs. nonclassical PEV mutations.
Analysis of Temperature-Sensitive Mutants Reveals New Genes Involved in the Courtship Song of Drosophila
Authors: Peixoto Alexandre A , Hall Jeffrey C
Published: July 2021

cacophony (cac), a mutation affecting the courtship song in Drosophila melanogaster, is revealed to cause temperature-sensitive (TS) abnormalities. When exposed to high temperatures (37°), cac flies show frequent convulsions and pronounced locomotor defects. This TS phenotype seems consistent with the idea that cac is a mutation in a calcium-channel gene; it maps to the same X-chromosomal locus that encodes the polypeptide comprising the α-1 subunit of this membrane protein. Analysis of the courtship song of some TS physiological mutants showed that slowpoke mutations, which affect a calcium-activated potassium channel, cause severe song abnormalities. Certain additional TS mutants, in particular parats1 and napts1, exhibit subtler song defects. The results therefore suggest that genes involved in ion-channel function are a potential source of intraspecific genetic variation for song parameters, such as the number of cycles present in “pulses” of tone or the rate at which pulses are produced by the male's courtship wing vibrations. The implications of these findings from the perspective of interspecific lovesong variations in Drosophila are discussed.
A Detailed Linkage Map of Rainbow Trout Produced Using Doubled Haploids
Authors: Young William P , Wheeler Paul A , Coryell Virginia H , Keim Paul , Thorgaard Gary H
Published: July 2021

We report the first detailed genetic linkage map of rainbow trout (Oncorhynchus mykiss). The segregation analysis was performed using 76 doubled haploid rainbow trout produced by androgenesis from a hybrid between the “OSU” and “Arlee” androgenetically derived homozygous lines. Four hundred and seventy-six markers segregated into 31 major linkage groups and 11 small groups (<5 markers/group). The minimum genome size is estimated to be 2627.5 cM in length. The sex-determining locus segregated to a distal position on one of the linkage groups. We analyzed the chromosomal distribution of three classes of markers: (1) amplified fragment length polymorphisms, (2) variable number of tandem repeats, and (3) markers obtained using probes homologous to the 5′ or 3′ end of salmonid-specific small interspersed nuclear elements. Many of the first class of markers were clustered in regions that appear to correspond to centromeres. The second class of markers were more telomeric in distribution, and the third class were intermediate. Tetrasomic inheritance, apparently related to the tetraploid ancestry of salmonid fishes, was detected at one simple sequence repeat locus and suggested by the presence of one extremely large linkage group that appeared to consist of two smaller groups linked at their tips. The double haploid rainbow trout lines and linkage map present a foundation for further genomic studies.
Genetic Interactions Among Late-Flowering Mutants of Arabidopsis
Authors: Koornneef M , Alonso-Blanco C , Vries H Blankestijn-de , Hanhart C J , Peeters A J M
Published: July 2021

Flowering time in Arabidopsis is controlled by a large number of genes, identified by induced mutations. Forty-two double mutants involving 10 of these loci were obtained and analyzed for their flowering behavior under long-day conditions, with and without vernalization, and under short-day conditions. The genetic interactions between the various mutants proved to be complex, although a major epistatic group (called group A) could be identified corresponding to the mutants, which are relatively insensitive to vernalization and daylength. In contrast, the genetic behavior of the mutants much more responsive to these environmental factors (group B) is more complex. The vernalization responsiveness of the group B mutants did not compensate for the lateness of the group A mutants. This indicated that these genes do not control vernalization sensitivity as such, but provide a factor that becomes limiting in short days. The classification of these mutants in different physiological groups is discussed in relation to the detected genetic interactions, and based on these interactions a more detailed model of their role in flowering initiation is proposed.
Properties and unbiased estimation of F- and D-statistics in samples containing related and inbred individuals
Authors: Mughal Mehreen R , DeGiorgio Michael
Published: July 2021

The Patterson F- and D-statistics are commonly used measures for quantifying population relationships and for testing hypotheses about demographic history. These statistics make use of allele frequency information across populations to infer different aspects of population history, such as population structure and introgression events. Inclusion of related or inbred individuals can bias such statistics, which may often lead to the filtering of such individuals. Here, we derive statistical properties of the F- and D-statistics, including their biases due to the inclusion of related or inbred individuals, their variances, and their corresponding mean squared errors. Moreover, for those statistics that are biased, we develop unbiased estimators and evaluate the variances of these new quantities. Comparisons of the new unbiased statistics to the originals demonstrates that our newly derived statistics often have lower error across a wide population parameter space. Furthermore, we apply these unbiased estimators using several global human populations with the inclusion of related individuals to highlight their application on an empirical dataset. Finally, we implement these unbiased estimators in open-source software package funbiased for easy application by the scientific community.
2015–2016 Normative Data for the 3-m Usual Walk, Five Repeated Chair Stands, and Static Balance Components of the SPPB Among U.S. Older Adults Across Two Nationally Representative Data Sets: NSHAP and NHATS
Authors: Huisingh-Scheetz Megan , Buta Brian , Bandeen-Roche Karen , Huang Elbert S , Varadhan Ravi , Walston Jeremy , Wroblewski Kristen , Schumm L Philip , Waite Linda J
Published: July 2021

Objectives

Our primary objective was to examine the distribution of 3-m usual walk, five repeated chair stands, and three static balance stance performances among age and gender subgroups of adults at least 65 years in two national data sets. We secondarily determined whether demographic–function associations varied across data sets, birth cohorts, or models incorporating data from those “unable to do” tasks.

Methods

Two nationally representative data sets were used to generate survey weight-adjusted performance distributions: the 2015–2016 National Social Life Health and Aging Project and the 2016 National Health and Aging Trends Study. We then regressed walk and chair stand performance on age, gender, and race/ethnicity, examining differences across data sets, birth cohorts (1920–1947, 1948–1965), and before/after incorporating the “unable to do” performers.

Results

Findings confirmed the gradual decline in function with age and allowed estimation of “relative” performance within age/gender subgroups. Data set distribution differences were noted, possibly due to recruitment, eligibility, and protocol variations. Demographic associations were similar across data sets but generally weaker among the 1948–1965 cohort and in models including the sizable “unable to do” group.

Discussion

We present the largest, most current Short Physical Performance Battery reference data in U.S. adults aged 65 or older. Findings support standardization of administration protocols in research and clinical care and differentiating absolute from relative performance.
16. Human rights
Authors: Firth Clare , Seymour Jennifer , Crompton Lucy , Fox Helen , Seabridge Frances , Seymour Jennifer , Smart Elizabeth
Published: July 2021

This chapter provides an introduction to the European Convention on Human Rights and the Human Rights Act 1998, taking into account the origins of the Convention and the Human Rights Act 1998 and their incorporation into UK legislation; the general principles of European jurisprudence; the Articles and the Protocols themselves; and areas where potential breaches may occur.
3. The Powers to Stop, Search, and Arrest
Authors: Hannibal Martin , Mountford Lisa
Published: July 2021

The police have extensive statutory powers to stop and search and to arrest a person in connection with the investigation of a criminal offence under various statutes, including the Police and Criminal Evidence Act 1984 (PACE 1984), the Terrorism Act 2000, the Misuse of Drugs Act 1971, and the Serious Organised Crime and Police Act 2005. This chapter examines the powers of stop and search before arrest; powers of arrest under PACE 1984; powers to search a person and his property after arrest; the power to grant street bail; and the right to liberty under Article 5 European Convention on Human Rights (ECHR 1950).
14. Trial Before the Crown Court
Authors: Hannibal Martin , Mountford Lisa
Published: July 2021

This chapter considers the procedural and practical steps at a trial on indictment. It examines the rules dealing with the indictment; supporting counsel at trial; empanelling the jury; the presentation of the prosecution and defence cases; the judge’s summing-up; and the jury’s verdict.
19. Character Evidence and the Accused as a Witness at Trial
Authors: Hannibal Martin , Mountford Lisa
Published: July 2021

This chapter examines the evidential rules that apply to the defendant at trial. These include the defendant’s competence and compellability; the course of the defendant’s evidence; drawing an adverse inference under s. 35 Criminal Justice and Public Order Act 1994 from the defendant’s silence at trial; the admissibility of a defendant’s past bad character; admissibility of defendant’s good character; and arguments for and against the defendant giving evidence.
25. Prosecuting Young Offenders
Authors: Hannibal Martin , Mountford Lisa
Published: July 2021

Where a prosecution is commenced against a child aged 10 to 13 years or against a young person aged 14 to 17 years, the general rule is that he will be tried and sentenced in the youth court. The youth court adopts more informal and less adversarial procedures to deal with the needs and vulnerabilities of young defendants. However, there are exceptional situations (grave offences and dangerous offenders) where they will be tried in the Crown Court or when jointly charged with an adult sometimes in the adult magistrates’ court. This chapter discusses the rules for deciding where a young person is to be tried; the rules for trying a young person in the Crown Court; the rules for trying a young person in the adult magistrates’ court; the young defendant’s right to court bail; and the procedure in the youth court.
14. The articles of a private company
Authors: Slorach J. Scott , Ellis Jason
Published: July 2021

This chapter considers some of the major issues which the articles of association of a private company are likely to address and the way in which the articles of a company can be altered and any restrictions thereto. It covers provisions concerning shares and membership; provisions concerning meetings of shareholders; provisions concerning directors; single member companies; and alteration of articles.
20. Taxation of distributions and debenture interest
Authors: Slorach J. Scott , Ellis Jason
Published: July 2021

This chapter deals with the taxation of distributions by way of dividend and of debenture interest. Both dividends and debenture interest are income returns on investments made in companies and, therefore, subject to income tax.
25. Company insolvency proceedings
Authors: Slorach J. Scott , Ellis Jason
Published: July 2021

This chapter deals with the procedures available when a company is insolvent or facing financial difficulties. It also considers the ways in which insolvent partnerships can be subject to the same procedures as companies. The law relating to these matters is principally contained in the Insolvency Act 1986 together with the Insolvency Rules 1986, as amended by the Insolvency Act 2000 and the Enterprise Act 2002. The insolvency legislation provides four procedures for companies in financial difficulties: administration, voluntary arrangement, receivership, and liquidation.
13. Default Judgment
Authors: Sime Stuart
Published: July 2021

Judgment in default may be entered where the defendant fails to defend a claim. It produces a judgment in favour of a claimant without holding a trial. This chapter discusses when default judgment may be entered; cases excluded from judgment in default; entering default judgment; final judgment and judgment for an amount to be decided; deciding the amount of damages; setting aside default judgments; and stay of undefended cases.
15. Track Allocation and Case Management
Authors: Sime Stuart
Published: July 2021

Judicial case management of civil litigation is one of the central planks of the Civil Procedure Rules 1998 (CPR). In exercising their powers to manage cases, the courts will be seeking to secure the overriding objective of the CPR of ensuring that cases are dealt with justly and at proportionate cost. This chapter discusses procedural judges; docketing; provisional track allocation; filing directions questionnaires; track allocation rules; notice of allocation; allocation directions; ADR and stays to allow for settlement; transfer to appropriate court; trial in the Royal Courts of Justice; changing tracks; and subsequent case management.
19. Parties and Joinder
Authors: Sime Stuart
Published: July 2021

This chapter first looks at the rules relating to different classes of party and then considers the rules governing multi-party litigation. Topics discussed include description of parties; particular classes of party; vexatious litigants; joinder; representative proceedings; representation of unascertained persons; intervention; consolidation; stakeholder claims; assignment; and group litigation.
25. Interim Payments
Authors: Sime Stuart
Published: July 2021

This chapter discusses the rules on interim payments. An order for interim payment is an order for payment of a sum of money by a defendant on account of any damages, debt, or other sum which the court may hold the defendant liable to pay. Such orders are likely to be made in claims where it appears that the claimant will achieve at least some success, and where it would be unjust to delay, until after the trial, payment of the money to which the claimant appears to be entitled. The amount ordered must not exceed a reasonable proportion of the likely final award taking into account any counterclaim and contributory negligence.
45. Norwich Pharmacal and Related Disclosure Orders
Authors: Sime Stuart
Published: July 2021

This chapter considers a number of other special forms of disclosure orders, the best known of which is the Norwich Pharmacal order. Norwich Pharmacal orders are primarily used for finding the identity of an unknown potential defendant. They can only be sought against a person who facilitated and got ‘mixed up’ in the wrongdoing. Norwich Pharmacal orders therefore cannot be made against ‘mere witnesses’. Pre-action disclosure orders bring forward the time when disclosure of documents takes place to the period before a claim is issued. Disclosure against non-parties enables the court to order a witness to produce documents in advance of the trial, thus avoiding adjournments when documents are produced at the last minute at trial.
46. Costs
Authors: Sime Stuart
Published: July 2021

This chapter focuses on legal costs. It discusses the two main principles for deciding which party should pay the costs of an application or of the whole proceedings; the rule that costs follow the event; range of possible costs orders; interim costs orders; indemnity principle; basis of quantification; proportionality; summary and detailed assessments; fast track fixed costs; fixed and scale costs; costs and track allocation; publicly funded litigants; pro bono costs orders; costs against non-parties; and wasted costs orders.
Mining Men: Reflections on Masculinity and Oral History during the Coronavirus Pandemic
Authors: Peirson-Webber Emily
Published: July 2021

The COVID-19 pandemic has disrupted our ability to undertake oral history research as it is traditionally understood, where interviewer and interviewee are in dialogue with each other in a shared physical setting. Reflecting on experiences conducting twenty-seven remote interviews with former British mineworkers, this article explores how meaningful interviews can be produced with certain groups via video conferencing software and over the telephone. While some of the observational benefits of in-person interviewing were lost, there were gains in terms of the comfort of interviewees and interviewer alike. The reciprocity of video conferencing software went some way to disrupt the power dynamics of oral history interviews. Likewise, interviewees seemed more self-reflexive and willing to discuss sensitive topics when talking via online video-conferencing platforms than over the telephone, or inperson. My experience demands that we rethink orthodox methodological advice concerning best practice. The remote oral history interview can allow access to groups who are hard to reach, and offers a means through which vulnerable interviewees can regain some sense of identity and agency in a time of social dislocation.
Mid-term clinical and haemodynamic results after aortic valve replacement with the Trifecta bioprosthesis
Authors: Mortelé Augustijn , Dereu Alexander , Bové Thierry , François Katrien
Published: July 2021

OBJECTIVES

The aim of this study was to evaluate the clinical and haemodynamic results after implantation of the Trifecta bioprosthesis.

METHODS

This study is a retrospective analysis of all patients undergoing Trifecta aortic valve replacement between 01 January 2012 and 31 December 2017 at the Ghent University Hospital. Univariable and multivariable analyses were performed to identify predictors of valve- and procedure-related complications and mortality. The haemodynamic performance was analysed by longitudinal Doppler echocardiography.

RESULTS

The mean age of the 182 patients was 77 [standard deviation (SD): 5.5] years; 54.9% were women. The mean follow-up was 39.8 (SD: 24.3) months. Overall survival at 1 and 5 years was 86% (SD: 3%) and 68% (SD: 4%), respectively, and overall freedom from structural valve deterioration was 100% and 98% at 1 and 5 years, respectively. There was no valve thrombosis nor early endocarditis. Urgent surgery was the only risk factor for early mortality in the multivariable analysis [P = 0.009, odds ratio 0.06, 95% confidence interval (CI) 0.01–0.5]. Preoperative atrial fibrillation was the most important predictor of late mortality (P = 0.001, hazard ratio 3.68, 95% CI 1.65–8.21). The average peak gradients were stable from discharge up to 1 and 5 years postoperatively [15 (SD: 6) and 17 (SD: 8) mmHg].

CONCLUSIONS

These results confirm the excellent clinical performance of the Trifecta valve, particularly in an elderly age group. Through the 7-year follow-up period, low transvalvular gradients persisted, and only a few patients needed reoperation. Although structural valve degeneration occurred rarely, it was unrelated to valve size or age at implantation; therefore, further long-term follow-up remains mandatory.
Intraoperative neuromonitoring in thoracoscopic excision of brachial plexus schwannoma
Authors: Femia Federico , Junemann Carola , Ruffini Enrico , Guerrera Francesco
Published: July 2021

Mediastinal schwannoma arising from brachial plexus are rare, but their surgical treatment could be challenging with a minimally invasive approach, given their position. Furthermore, their proximity to brachial plexus nerve fibres raises the risk for postoperative upper limb deficits. A 72-year-old man presented mediastinal schwannoma arising from the T1 nerve root. Complete surgical excision was achieved via video-assisted thoracic surgery with the aid of intraoperative neuromonitoring, and no postoperative neurological deficit developed after the intervention. Using intraoperative neuromonitoring, radical minimally invasive surgical treatment can be safely achieved for mediastinal schwannoma arising from brachial plexus.
The mechanical origin of the radial shape in distichous phyllotaxy grass plants
Authors: Tokuyama Yoshiki , Koide Yohei , Onishi Kazumitsu , Hikichi Kiwamu , Omachi Miku , Takamure Itsuro , Kishima Yuji
Published: July 2021

Three-dimensional plant shapes are influenced by their phyllotaxy, which plays a significant role in their environmental adaptation. Grasses with distichous phyllotaxy have linearly aligned culms and usually have vertical fan-like shapes. Counterintuitively, some distichous phyllotaxy grasses have radial shapes. Here, we investigate the organ-level mechanism underlying radial shape development in the distichous phyllotactic wild rice species (Oryza rufipogon). Detailed time-course phenotyping and three-dimensional micro-computed tomography showed that changes in the elevation angle in the main culm and azimuth angle in the primary tillers contribute to radial shape development. To infer the mechanical basis of the shape change, we simulated the movements of culms controlled by different kinematic factors. The computational models predicted that the combination of movements, including that controlled by negative gravitropism, produces the overall radial shape. This prediction was experimentally assessed. The analysis using a near-isogenic line of the gene, PROG1 for prostrate growth and the gravitropic mutant (lazy1) showed an association between genes and our model parameters. Our findings provide a simple, yet substantial, kinematic model for how the shape in distichous phyllotaxy plants changes as part of their adaptation to the surrounding environment.
Quality gap in venous thromboembolism prophylaxis practices in inpatients: Assessment of prophylaxis practices in a University Hospital
Authors: Güven Alper Tuna , Altintop Sabri Engin , Özdede Murat , Uyaroğlu Oğuz Abdullah , Tanriöver Mine Durusu
Published: July 2021

Background

Venous thromboembolism (VTE) is a prevalent complication of inpatient care, causing high burden of morbidity and mortality. Prophylaxis reduces the events; thus, these practices are promoted. We aimed to assess the VTE prophylaxis practices in the general internal medicine wards of a tertiary-care university hospital and utilize these data to propose quality improvement projects.

Objective

Assess the pharmacological venous thromboembolism prophylaxis utilization by using the Padua Prediction Score and demonstrate the main determinants of inappropriate prophylaxis use.

Methods

Electronic medical records were used to collect data cross-sectionally from 1 January 2019 to 30 June 2019. Padua Prediction Score was used to assess the appropriateness of VTE prophylaxis. Underlying health conditions, hospitalization causes, anti-platelets and use of glucocorticoids were also assessed as confounding factors.

Results

A total of 295 patients were included. Higher proportion of patients who received VTE prophylaxis were obese and had higher rates of diabetes and coronary artery disease. Prophylaxis was more commonly utilized among patients who were elderly, obese, having an acute infection and/or rheumatologic disorder and prolonged bed rest (P ≤ 0.001, P = 0.01, P = 0.22 and P ≤ 0.001, respectively). Thirty-five patients (11.8%) received VTE prophylaxis, despite 89 patients (30.2%) were high-risk patients. In the high-risk group (n = 89), 27 patients (30.3%) received appropriate pharmacological prophylaxis, while 8 patients (3.9%) received VTE prophylaxis in the low-risk group (total n = 206). A considerable percentage of the high-risk population (69.6%) did not receive VTE prophylaxis.

Discussion

Underuse constitutes a major challenge in our hospital but differing from other institutions, overuse is not a significant issue. Further studies are needed whether VTE prophylaxis improvement implementations uniformly increase appropriate VTE use.
How to Hold Unjust Structures Responsible in International Relations
Authors: Srivastava Swati , Muscott Lauren
Published: July 2021

Recent public discourse and political theory center on “structural” approaches of assigning responsibility for injustice in contrast to an “interactional” perspective. The interactional approach corrects discrete harms between agents to return to a just baseline, whereas the structural approach casts a wider net implicating agents in harmful structures for systemic transformation. This theory note advances the understanding of structural responsibility in international relations by defending it against common critiques of underspecification and lack of targeted accountability. We argue that structural arguments are better understood as constituting a framework on the nature of injustice rather than a theory or descriptor of particular harms. We present a “framework, theory, action” heuristic, drawing from constructivism's evolution from a theory (like realism and liberalism) when it first appeared to a framework (like rationalism) more recently. Our framework heuristic makes available a fuller range of conceptual tools to hold unjust structures responsible, including through targeted blame and liability, and discards the need to invent new actions to discharge structural responsibility. Rather than settle on one definition of structural responsibility—what it means, where it is located, and how it is discharged—we direct scholars to the numerous ways structural responsibility may be theorized and enacted.
Advances on (+)-nootkatone microbial biosynthesis and its related enzymes
Authors: Li Xiao , Ren Jing-Nan , Fan Gang , Zhang Lu-Lu , Pan Si-Yi
Published: July 2021

(+)-Nootkatone is an important functional sesquiterpene and is comprehensively used in pharmaceutical, cosmetic, agricultural and food flavor industries. However, (+)-nootkatone is accumulated trace amounts in plants, and the demand for industry is mainly met by chemical methods which is harmful to the environment. The oxygen-containing sesquiterpenes prepared using microbial methods can be considered as “natural.” Microbial transformation has the advantages of mild reaction conditions, high efficiency, environmental protection, and strong stereoselectivity, and has become an important method for the production of natural spices. The microbial biosynthesis of (+)-nootkatone from the main precursor (+)-valencene is summarized in this paper. Whole-cell systems of fungi, bacteria, microalgae, and plant cells have been employed. It was described that the enzymes involved in the microbial biosynthesis of (+)-nootkatone, including cytochrome p450 enzymes, laccase, lipoxygenase, and so on. More recently, the related enzymes were expressed in microbial hosts to heterologous produce (+)-nootkatone, such as Escherichia coli, Pichia pastoris, Yarrowia lipolytica, and Saccharomyces cerevisiae. Finally, the development direction of research for realizing industrialization of microbial transformation was summarized and it provided many options for future improved bioprocesses.
Human neuromuscular junction three-dimensional organoid models and the insight in motor disorders
Authors: Zhang Kejing , Bai Lei , Xu Wentao , Shen Chengyong
Published: July 2021

The neuromuscular junction (NMJ), a peripheral synaptic connection between motoneurons and skeletal muscle fibers, controls movement. Dysregulation of NMJs has been implicated in various motor disorders. Because of their large size and easy accessibility, NMJs have been extensively investigated in the neuroscience field and have greatly contributed to our understanding of the fundamental principles of synapses in the central nervous system. Researchers have tried multiple ways to develop models to recreate NMJs. Rapid progress in the research and development of tissue-like organoids has made it possible to produce human NMJ three-dimensional (3D) models in vitro, providing an additional powerful strategy to study NMJs. Here, we introduce the most recent advances of human embryonic stem cell- or induced pluripotent stem cell-derived organoids to model 3D NMJs.
Evolution in X-ray analysis from micro to atomic scales in aberration-corrected scanning transmission electron microscopes
Authors: Watanabe M , Egerton R F
Published: July 2021

X-ray analysis is one of the most robust approaches to extract quantitative information from various materials and is widely used in various fields ever since Raimond Castaing established procedures to analyze electron-induced X-ray signals for materials characterization ‘70 years ago’. The recent development of aberration-correction technology in a (scanning) transmission electron microscopes (S/TEMs) offers refined electron probes below the Å level, making atomic-resolution X-ray analysis possible. In addition, the latest silicon drift detectors allow complex detector arrangements and new configurational designs to maximize the collection efficiency of X-ray signals, which make it feasible to acquire X-ray signals from single atoms. In this review paper, recent progress and advantages related to S/TEM-based X-ray analysis will be discussed: (i) progress in quantification for materials characterization including the recent applications to light element analysis, (ii) progress in analytical spatial resolution for atomic-resolution analysis and (iii) progress in analytical sensitivity toward single-atom detection and analysis in materials. Both atomic-resolution analysis and single-atom analysis are evaluated theoretically through multislice-based calculation for electron propagation in oriented crystalline specimen in combination with X-ray spectrum simulation.
Visualization of Arabidopsis root system architecture in 3D by refraction-contrast X-ray micro-computed tomography
Authors: Kurogane Tomofumi , Tamaoki Daisuke , Yano Sachiko , Tanigaki Fumiaki , Shimazu Toru , Kasahara Haruo , Yamauchi Daisuke , Uesugi Kentaro , Hoshino Masato , Kamisaka Seiichiro , Mineyuki Yoshinobu , Karahara Ichirou
Published: July 2021

Plant roots change their morphological traits in order to adapt themselves to different environmental conditions, resulting in the alteration of the root system architecture. To understand this mechanism, it is essential to visualize the morphology of the entire root system. To reveal effects of long-term alteration of gravity environment on root system development, we have performed an experiment in the International Space Station using Arabidopsis plants and obtained dried root systems grown in rockwool slabs. The X-ray computed tomography (CT) technique using industrial X-ray scanners has been introduced to visualize the root system architecture of crop species grown in soil in 3D non-invasively. In the case of the present study, however, the root system of Arabidopsis is composed of finer roots compared with typical crop plants and rockwool is also composed of fibers having similar dimension to that of the roots. A higher spatial resolution imaging method is required for distinguishing roots from rockwool. Therefore, in the present study, we tested refraction-contrast X-ray micro-CT using coherent X-ray optics available at the beamline of the synchrotron radiation facility SPring-8 for bio-imaging. We have found that a wide field of view but with low resolution obtained at the experimental Hutch 3 of this beamline provided an overview map of the root systems, while a narrow field of view but with high resolution obtained at the experimental Hutch 1 provided an extended architecture of the secondary roots, by a clear distinction between roots and individual rockwool fibers, resulting in the successful tracing of these roots from their basal regions.
Atypical primary hyperparathyroidism due to parathyroid lipoadenoma: a case report
Authors: Cammarata Francesco , Yakushkina Al’ona , Pennacchi Luca , Carsana Luca , Zerbi Pietro , Montecamozzo Giulio , Danelli Piergiorgio
Published: July 2021

Parathyroid lipoadenoma is a very rare cause of primary hyperparathyroidism. Preoperative imaging techniques often fail to detect such lesions, and even during surgery they can be misinterpreted just as fat tissue. A 62-year-old woman clinically monitored for primary hyperparathyroidism, with hypertension and a left nephrectomy for hydrouretheronephrosis caused by recurrent kidney stones. A neck ultrasound showed a nodule consistent with left parathyroid of 9 × 5 mm, which was not confirmed on single-photon-emission computed tomography/computed tomography (CT) scan. On surgery, a voluminous lesion with adipose appearance and texture was removed. Frozen sections and intraoperative parathyroid hormone (PTH) confirmed such lesion to be a parathyroid lipoadenoma. Parathyroid lipoadenomas are difficult to localize preoperatively. Sometimes they can be seen by ultrasound scan as hyperechoich lesion, but scintigraphy and CT often fail to identify them. Only the awareness of such lesions and the use of intraoperative PTH can avoid unnecessary extensive cervical exploration.
Dissipative dark matter on FIRE – I. Structural and kinematic properties of dwarf galaxies
Authors: Shen Xuejian , Hopkins Philip F , Necib Lina , Jiang Fangzhou , Boylan-Kolchin Michael , Wetzel Andrew
Published: July 2021

We present the first set of cosmological baryonic zoom-in simulations of galaxies including dissipative self-interacting dark matter (dSIDM). These simulations utilize the Feedback In Realistic Environments galaxy formation physics, but allow the dark matter to have dissipative self-interactions analogous to standard model forces, parametrized by the self-interaction cross-section per unit mass, (σ/m), and the dimensionless degree of dissipation, 0 < fdiss < 1. We survey this parameter space, including constant and velocity-dependent cross-sections, and focus on structural and kinematic properties of dwarf galaxies with $M_{\rm halo} \sim 10^{10-11}{\, \rm M_\odot }$ and $M_{\ast } \sim 10^{5-8}{\, \rm M_\odot }$. Central density profiles (parametrized as ρ ∝ rα) of simulated dwarfs become cuspy when $(\sigma /m)_{\rm eff} \gtrsim 0.1\, {\rm cm^{2}\, g^{-1}}$ (and fdiss = 0.5 as fiducial). The power-law slopes asymptote to α ≈ −1.5 in low-mass dwarfs independent of cross-section, which arises from a dark matter ‘cooling flow’. Through comparisons with dark matter only simulations, we find the profile in this regime is insensitive to the inclusion of baryons. However, when $(\sigma /m)_{\rm eff} \ll 0.1\, {\rm cm^{2}\, g^{-1}}$, baryonic effects can produce cored density profiles comparable to non-dissipative cold dark matter (CDM) runs but at smaller radii. Simulated galaxies with $(\sigma /m) \gtrsim 10\, {\rm cm^{2}\, g^{-1}}$ and the fiducial fdiss develop significant coherent rotation of dark matter, accompanied by halo deformation, but this is unlike the well-defined thin ‘dark discs’ often attributed to baryon-like dSIDM. The density profiles in this high cross-section model exhibit lower normalizations given the onset of halo deformation. For our surveyed dSIDM parameters, halo masses and galaxy stellar masses do not show appreciable difference from CDM, but dark matter kinematics and halo concentrations/shapes can differ.
A differentiable N-body code for transit timing and dynamical modelling – I. Algorithm and derivatives
Authors: Agol Eric , Hernandez David M , Langford Zachary
Published: July 2021

When fitting N-body models to astronomical data – such as transit times, radial velocity, and astrometric positions at observed times – the derivatives of the model outputs with respect to the initial conditions can help with model optimization and posterior sampling. Here, we describe a general purpose symplectic integrator for arbitrary orbital architectures, including those with close encounters, which we have recast to maintain numerical stability and precision for small step sizes. We compute the derivatives of the N-body coordinates and velocities as a function of time with respect to the initial conditions and masses by propagating the Jacobian along with the N-body integration. For the first time, we obtain the derivatives of the transit times with respect to the initial conditions and masses using the chain rule, which is quicker and more accurate than using finite differences or automatic differentiation. We implement this algorithm in an open source package, NbodyGradient.jl, written in the Julia language, which has been used in the optimization and error analysis of transit-timing variations in the TRAPPIST-1 system. We present tests of the accuracy and precision of the code, and show that it compares favourably in speed to other integrators that are written in C.
Low-surface-brightness spheroidal galaxies as Milgromian isothermal spheres
Authors: Sanders R H
Published: July 2021

I consider a sample of eight pressure-supported low-surface-brightness galaxies in terms of Milgrom’s modified Newtonian dynamics (MOND). These objects include seven nearby dwarf spheroidal galaxies – Sextans, Carina, Leo II, Sculptor, Draco, Leo I, Fornax, and the ultra-diffuse galaxy DF44. The objects are modelled as Milgromian isotropic isothermal spheres characterized by two parameters that are constrained by observations: the constant line-of-sight velocity dispersion and the central surface density. The velocity dispersion determines the total mass, and, with the implied mass-to-light ratio, the central surface brightness. This then specifies the radial run of surface brightness over the entire isothermal sphere. For these objects, the predicted radial distribution of surface brightness is shown to be entirely consistent with observations. This constitutes a success for MOND that is independent of the reduced dynamical mass.
Reappraising Choice in Addiction: Novel Conceptualizations and Treatments for Tobacco Use Disorder
Authors: Palmer Amanda M , Toll Benjamin A , Carpenter Matthew J , Donny Eric C , Hatsukami Dorothy K , Rojewski Alana M , Smith Tracy T , Sofuoglu Mehmet , Thrul Johannes , Benowitz Neal L
Published: July 2021

The introduction of alternative nicotine and tobacco products (such as e-cigarettes, heat-not-burn devices, nicotine pouches) warrants an updated framework from which to conceptualize tobacco use disorder (TUD). The following review provides considerations for TUD within the context of novel products. Historically, the tobacco industry falsely claimed that cigarettes were not addictive or harmful and that those who smoked simply chose to do so. This generated an inaccurate lay perception that smoking is a free or informed choice. Research on nicotine pharmacology demonstrates the powerful addictive potential of nicotine, which is shaped by dose, speed of delivery, and other constituents generated. In addition, non-pharmacologic reinforcers motivate and maintain tobacco use behaviors for both traditional cigarettes and novel products. The negative consequences of combustible tobacco use are well known; however, these outcomes may differ for alternative products. Strategies used for combustible product cessation may be adapted for novel products, and treatment recommendations for TUD should be made within the context of a harm reduction framework wherein alternative product use may be the desired outcome. Providers must therefore be willing to modify their perceptions of products and treatment recommendations accordingly. Better public health outcomes are accomplished through promotion of abstinence from combustible smoking. For those who cannot wean from nicotine entirely, switching to less risky modes of delivery might be a secondary goal, with an eventual aim of stopping use of the alternative product.

Implications: Given the advent of novel, alternative tobacco products, tobacco use disorder (TUD) must be conceptualized within a contemporary framework that includes harm reduction and alternative outcomes. The unique contributions of nicotine pharmacology, non-pharmacologic reinforcers, and consequences of use can be used to inform treatments for TUD with the ultimate goal of improving the health of individuals who use tobacco.
Cerebral White Matter Alterations Revealed by Multiple Diffusion Metrics in Cervical Spondylotic Patients with Pain: A TBSS Study
Authors: Li Dan , Xu Hui , Yang Qian , Zhang Ming , Wang Yuan
Published: July 2021

Objective

The aims of the present study were to investigate white matter alterations and their associations with the clinical variables in cervical spondylotic (CS) patients with pain.

Design

Cross-sectional study.

Setting

Chinese community.

Subjects

Forty-two CS patients with pain and 42 matched healthy participants were ultimately recruited from August 2018 to September 2019.

Methods

Tract-based spatial statistics (TBSS) analysis was performed to investigate the differences of DTI-derived indices (fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD)) between the patients and healthy controls throughout brain white matter. The relationship of the severity of cervical pain and affective disturbance to aberrant DTI indices in the patients was also examined using spearman correlation analyses.

Results

The CS patients with pain showed decreased FA in the genu, body, and splenium portions of corpus callosum (CC), and increased MD and RD along with decreased FA in anterior corona radiata (ACR) compared with healthy controls, whereas no significant difference of AD was observed between groups. Additionally, lower FA of the genu part of CC together with higher MD of the left ACR were statistically correlated with the pain severity in the patient group.

Conclusions

Decreased FA coupled with increased MD and RD was detected in multiple white matter regions, and several DTI metrics in certain white matter tracts had moderate relationships with the pain severity in the CS patients with pain. These observations may provide alternative imaging clues for the evaluation of the pathophysiological characteristics of CS pain.
Thyroid Disruptors: Extrathyroidal Sites of Chemical Action and Neurodevelopmental Outcome—An Examination Using Triclosan and Perfluorohexane Sulfonate
Authors: Gilbert Mary E , O’Shaughnessy Katherine L , Thomas Susan E , Riutta Cal , Wood Carmen R , Smith Alicia , Oshiro Wendy O , Ford Richard L , Hotchkiss Michelle Gatien , Hassan Iman , Ford Jermaine L
Published: July 2021

Many xenobiotics are identified as potential thyroid disruptors due to their action to reduce circulating levels of thyroid hormone, most notably thyroxine (T4). Developmental neurotoxicity is a primary concern for thyroid disrupting chemicals yet correlating the impact of chemically induced changes in serum T4 to perturbed brain development remains elusive. A number of thyroid-specific neurodevelopmental assays have been proposed, based largely on the model thyroid hormone synthesis inhibitor propylthiouracil (PTU). This study examined whether thyroid disrupting chemicals acting distinct from synthesis inhibition would result in the same alterations in brain as expected with PTU. The perfluoroalkyl substance perfluorohexane sulfonate (50 mg/kg/day) and the antimicrobial Triclosan (300 mg/kg/day) were administered to pregnant rats from gestational day 6 to postnatal day (PN) 21, and a number of PTU-defined assays for neurotoxicity evaluated. Both chemicals reduced serum T4 but did not increase thyroid stimulating hormone. Both chemicals increased expression of hepatic metabolism genes, while thyroid hormone-responsive genes in the liver, thyroid gland, and brain were largely unchanged. Brain tissue T4 was reduced in newborns, but despite persistent T4 reductions in serum, had recovered in the PN6 pup brain. Neither treatment resulted in a low dose PTU-like phenotype in either brain morphology or neurobehavior, raising questions for the interpretation of serum biomarkers in regulatory toxicology. They further suggest that reliance on serum hormones as prescriptive of specific neurodevelopmental outcomes may be too simplistic and to understand thyroid-mediated neurotoxicity we must expand our thinking beyond that which follows thyroid hormone synthesis inhibition.
A Sulfonyl Azide-Based Sulfide Scavenger Rescues Mice from Lethal Hydrogen Sulfide Intoxication
Authors: Miyazaki Yusuke , Marutani Eizo , Ikeda Takamitsu , Ni Xiang , Hanaoka Kenjiro , Xian Ming , Ichinose Fumito
Published: July 2021

Exposure to hydrogen sulfide (H2S) can cause neurotoxicity and cardiopulmonary arrest. Resuscitating victims of sulfide intoxication is extremely difficult, and survivors often exhibit persistent neurological deficits. However, no specific antidote is available for sulfide intoxication. The objective of this study was to examine whether administration of a sulfonyl azide-based sulfide-specific scavenger, SS20, would rescue mice in models of H2S intoxication: ongoing exposure and post-cardiopulmonary arrest. In the ongoing exposure model, SS20 (1250 µmol/kg) or vehicle was administered to awake CD-1 mice intraperitoneally at 10 min after breathing 790 ppm of H2S followed by another 30 min of H2S inhalation. Effects of SS20 on survival were assessed. In the post-cardiopulmonary arrest model, cardiopulmonary arrest was induced by an intraperitoneal administration of sodium sulfide nonahydrate (125 mg/kg) in anesthetized mice. After 1 min of cardiopulmonary arrest, mice were resuscitated with intravenous administration of SS20 (250 µmol/kg) or vehicle. Effects of SS20 on survival, neurological outcomes, and plasma H2S levels were evaluated. Administration of SS20 during ongoing H2S inhalation improved 24-h survival (6/6 [100%] in SS20 vs 1/6 [17%] in vehicle; p = .0043). Post-arrest administration of SS20 improved 7-day survival (4/10 [40%] in SS20 vs 0/10 [0%] in vehicle; p = .0038) and neurological outcomes after resuscitation. SS20 decreased plasma H2S levels to pre-arrest baseline immediately after reperfusion and shortened the time to return of spontaneous circulation and respiration. These results suggest that SS20 is an effective antidote against lethal H2S intoxication, even when administered after cardiopulmonary arrest.
Experiences, Attitudes, and Perceptions of Female Adjunct Clinical Instructors in Teaching Male Prelicensure Nursing Students
Authors: Shilo Amanda
Published: July 2021

Male students often report experiencing barriers during nursing education, resulting in decreased retention and success. Clinical instructors are one influence that potentially deters men in nursing. This qualitative study interviewed female clinical instructors about their experiences, attitudes, and perceptions of teaching males. The results reveal a general acceptance of males, with hesitation and ambivalence from some clinical instructors. Further training for clinical instructors, education of the public, and recruitment of more males into education are suggested to improve male student outcomes.