bluuebunny/crossref_metadata_2025 huggingface dataset:
Central importance of emotional and quality-of-life outcomes in the public’s perception of face transplantation
Authors: Murphy D C , Hoyle V , Saleh D , Rees J , Bound Alberti F
Published: March 2021

Background

Face transplantation is a surgical innovation to manage people with severely interrupted facial function and form. How the public perceive face transplantation and its potential implications for the recipient, donor, and society is unclear. The aim of this study was to understand the public perception of face transplantation, including when it is appropriate, what information is required to feel adequately informed, and which factors influence a person’s willingness to donate their face.

Methods

This was a nationwide survey of participants representative of the GB public. A quantitative analysis was performed. Free-text qualitative responses were coded with thematic content analysis and a narrative analysis was constructed.

Results

The survey included 2122 participants. Face transplantation was considered worth the potential risks if it improved an individual’s quality of life, gave them a ‘normal life’, and/or increased their confidence and social interaction. Respondents were worried about the impact face transplantation might have on donor families, especially recipient families adapting to the identity of the donor. Respondents most concerned about the concept of face transplantation were aged at least 55 years (χ2(4) = 38.9, P < 0.001), women (χ2(1) = 19.8, P < 0.001) , and Indian/Asian (χ2(4) = 11.9, P = 0.016).

Conclusion

The public perceive emotional and psychological outcomes as equally as important as, or more important than, surgical outcomes when determining the appropriateness of face transplantation. Future research should focus on measuring and describing emotional and psychological outcomes after face transplantation.
Contralateral exploration and repair of occult inguinal hernias during laparoscopic inguinal hernia repair: systematic review and Markov decision process
Authors: Dhanani N H , Olavarria O A , Wootton S , Petsalis M , Lyons N B , Ko T C , Kao L S , Liang M K
Published: March 2021

Background

Contralateral clinically occult hernias are frequently noted at the time of laparoscopic unilateral inguinal hernia repair. There is no consensus on the role of contralateral exploration and repair. This systematic review assessed the safety and efficacy of operative repair of occult contralateral inguinal hernias found during unilateral repair.

Methods

PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched from inception to February 2020. Adults diagnosed with a unilateral inguinal hernia undergoing laparoscopic repair were included. The primary outcome was the incidence of occult contralateral hernias. Summative outcomes of operative and expectant management were reported along with development of a Markov decision process.

Results

Thirteen studies (1 randomized trial, 12 observational cohorts) with 5000 patients were included. The incidence of occult contralateral inguinal hernias was 14.6 (range 7.3–50.1) per cent. Among patients who underwent repair, 10.5 (4.3–17.0) per cent experienced a postoperative complication. Of patients managed expectantly, 29 per cent later required elective repair for symptoms. Mean follow-up was 36 (range 2–218) months. Using a Markov decision process, it was calculated that, for every 1000 patients undergoing unilateral inguinal hernia repair, contralateral exploration would identify 150 patients with an occult hernia. Repair would result in 15 patients developing a postoperative complication and 105 undergoing unnecessary repair. Alternatively, expectant management would result in 45 patients requiring subsequent repair.

Conclusion

Contralateral repair is not warranted in patients with occult hernias diagnosed at the time of elective hernia repair. The evidence is largely based on observational studies at high risk of bias.
Residual lymph node tumour burden following removal of a single axillary sentinel lymph with macrometastatic disease in women with screen-detected invasive breast cancer
Authors: Dave R V , Cheung S , Sibbering M , Kearins O , Jenkins J , Gandhi A
Published: March 2021

Background

Women with screen-detected invasive breast cancer who have macrometastatic disease on axillary sentinel lymph node biopsy (SLNB) are usually offered either surgical axillary node clearance (ANC) or axillary radiotherapy. These treatments can lead to significant complications for patients. The aim of this study was to identify a group of patients who may not require completion ANC.

Methods

Data from the NHS Breast Screening Programme between 1 April 2012 and 31 March 2017 were interrogated to identify women with invasive breast carcinoma and a single sentinel lymph node (SLN) with macrometastatic disease who subsequently proceeded to completion ANC. Univariable and multivariable analyses were performed to identify patients with a single positive SLN who had no further lymph node metastasis on ANC.

Results

Of the 2401 women included in the cohort, the presence of non-sentinel node disease was significantly affected by: the number of nodes obtained at SLNB (odds ratio (OR) 0.49 for retrieval of more than 1 node), invasive size of tumour (OR 1.63 for size greater than 20 mm), surgical treatment (OR 1.34 for mastectomy), human epidermal growth factor receptor (HER) 2 status (OR 0.71 for HER2 positivity), and patient age (OR 1.10 for age less than 50 years; OR 1.46 for age greater than 70 years). Patients aged less than 70 years, with tumour size smaller than 2 cm, more than one node retrieved on SLNB, and who had breast-conserving surgery had a lower chance of positive non-sentinel nodes on completion ANC compared with other patients.

Conclusion

This study, of a purely screen-detected breast cancer cohort, identified a subset of patients who may be spared completion ANC in the event of a single axillary SLN with macrometastasis.
Impact of bodyweight-adjusted antimicrobial prophylaxis on surgical-site infection rates
Authors: Salm L , Marti W R , Stekhoven D J , Kindler C , Von Strauss M , Mujagic E , Weber W P
Published: March 2021

Background

Antimicrobial prophylaxis (AMP) adjustment according to bodyweight to prevent surgical-site infections (SSI) is controversial. The impact of weight-adjusted AMP dosing on SSI rates was investigated here.

Methods

Results from a first study of patients undergoing visceral, vascular or trauma operations, and receiving standard AMP, enabled retrospective evaluation of the impact of bodyweight and BMI on SSI rates, and identification of patients eligible for weight-adjusted AMP. In a subsequent observational prospective study, patients weighing at least 80 kg were assigned to receive double-dose AMP. Risk factors for SSI, including ASA classification, duration and type of surgery, wound class, diabetes, weight in kilograms, BMI, age, and AMP dose, were evaluated in multivariable analysis.

Results

In the first study (3508 patients), bodyweight and BMI significantly correlated with higher rates of all SSI subclasses (both P < 0.001). An 80-kg cut-off identified patients receiving single-dose AMP who were at higher risk of SSI. In the prospective study (2161 patients), 546 patients weighing 80 kg or more who received only single-dose AMP had higher rates of all SSI types than a group of 1615 who received double-dose AMP (odds ratio (OR) 4.40, 95 per cent c.i. 3.18 to 6.23; P < 0.001). In multivariable analysis including 5021 patients from both cohorts, bodyweight (OR 1.01, 1.00 to 1.02; P = 0.008), BMI (OR 1.01, 1.00 to 1.02; P = 0.007) and double-dose AMP (OR 0.33, 0.23 to 0.46; P < 0.001) among other variables were independently associated with SSI rates.

Conclusion

Double-dose AMP decreases SSI rates in patients weighing 80 kg or more.
Prevention of cardiac implantable electronic device infections: guidelines and conventional prophylaxis
Authors: Blomstrom-Lundqvist Carina , Ostrowska Bozena
Published: March 2021

Cardiac implantable electronic devices (CIED) are potentially life-saving treatments for several cardiac conditions, but are not without risk. Despite dissemination of recommended strategies for prevention of device infections, such as administration of antibiotics before implantation, infection rates continue to rise resulting in escalating health care costs. New trials conveying important steps for better prevention of device infection and an EHRA consensus paper were recently published. This document will review the role of various preventive measures for CIED infection, emphasizing the importance of adhering to published recommendations. The document aims to provide guidance on how to prevent CIED infections in clinical practice by considering modifiable and non-modifiable risk factors that may be present pre-, peri-, and/or post-procedure.
Physical inactivity in nine European and Central Asian countries: an analysis of national population-based survey results
Authors: Whiting Stephen , Mendes Romeu , Abu-Omar Karim , Gelius Peter , Crispo Anna , McColl Karen , Simmonds Phillipa , Fedkina Natalia , Andreasyan Dianne , Gahraman Hagverdiyev , Migal Tatyana , Sturua Lela , Obreja Galina , Abdurakhmanova Zulfinissio , Saparkulovna Ibraeva Nurgul , Erguder Toker , Ekinci Banu , Keskinkilic Bekir , Shukurov Shukhrat , Yuldashev Rustam , Berdzuli Nino , Rakovac Ivo , Breda Joao
Published: March 2021

Background

Physical inactivity is a major risk factor for non-communicable diseases. However, recent and systematically obtained national-level data to guide policy responses are often lacking, especially in countries in Eastern Europe and Central Asia. This article describes physical inactivity patterns among adults in Armenia, Azerbaijan, Belarus, Georgia, Kyrgyzstan, Republic of Moldova, Tajikistan, Turkey and Uzbekistan.

Methods

Data were collected using the Global Physical Activity Questionnaire drawing nationally representative samples of adults in each country. The national prevalence of physical inactivity was calculated as well as the proportional contribution to total physical activity (PA) during work, transport and leisure-time. An adjusted logistic regression model was applied to analyze the association of age, gender, education, household status and income with physical inactivity.

Results

National prevalence of physical inactivity ranged from 10.1% to 43.6%. The highest proportion of PA was registered during work or in the household in most countries, whereas the lowest was during leisure-time in all countries. Physical inactivity was more likely with older age in eight countries, with female gender in three countries, and with living alone in three countries. There was no clear pattern of association with education and income.

Conclusion

Prevalence of physical inactivity is heterogeneous across the region. PA during leisure-time contributes minimally to total PA in all countries. Policies and programs that increase opportunities for active travel and leisure-time PA, especially for older adults, women and people living alone will be an essential part of strategies to increase overall population PA.
Transcriptomic analysis of feminizing somatic stem cells in theDrosophilatestis reveals putative downstream effectors of the transcription factor Chinmo
Authors: Grmai Lydia , Harsh Sneh , Lu Sean , Korman Aryeh , Deb Ishan B , Bach Erika A
Published: March 2021

One of the best examples of sexual dimorphism is the development and function of the gonads, ovaries and testes, which produce sex-specific gametes, oocytes, and spermatids, respectively. The development of these specialized germ cells requires sex-matched somatic support cells. The sexual identity of somatic gonadal cells is specified during development and must be actively maintained during adulthood. We previously showed that the transcription factor Chinmo is required to ensure the male sexual identity of somatic support cells in the Drosophila melanogaster testis. Loss of chinmo from male somatic gonadal cells results in feminization: they transform from squamous to epithelial-like cells that resemble somatic cells in the female gonad but fail to properly ensheath the male germline, causing infertility. To identify potential target genes of Chinmo, we purified somatic cells deficient for chinmo from the adult Drosophila testis and performed next-generation sequencing to compare their transcriptome to that of control somatic cells. Bioinformatics revealed 304 and 1549 differentially upregulated and downregulated genes, respectively, upon loss of chinmo in early somatic cells. Using a combination of methods, we validated several differentially expressed genes. These data sets will be useful resources to the community.
Reduced gene dosage of histone H4 prevents CENP-A mislocalization and chromosomal instability in Saccharomyces cerevisiae
Authors: Eisenstatt Jessica R , Ohkuni Kentaro , Au Wei-Chun , Preston Olivia , Gliford Loran , Suva Evelyn , Costanzo Michael , Boone Charles , Basrai Munira A
Published: March 2021

Mislocalization of the centromeric histone H3 variant (Cse4 in budding yeast, CID in flies, CENP-A in humans) to noncentromeric regions contributes to chromosomal instability (CIN) in yeast, fly, and human cells. Overexpression and mislocalization of CENP-A have been observed in cancers, however, the mechanisms that facilitate the mislocalization of overexpressed CENP-A have not been fully explored. Defects in proteolysis of overexpressed Cse4 (GALCSE4) lead to its mislocalization and synthetic dosage lethality (SDL) in mutants for E3 ubiquitin ligases (Psh1, Slx5, SCFMet30, and SCFCdc4), Doa1, Hir2, and Cdc7. In contrast, defects in sumoylation of overexpressed cse4K215/216/A/R prevent its mislocalization and do not cause SDL in a psh1Δ strain. Here, we used a genome-wide screen to identify factors that facilitate the mislocalization of overexpressed Cse4 by characterizing suppressors of the psh1Δ GALCSE4 SDL. Deletions of histone H4 alleles (HHF1 or HHF2), which were among the most prominent suppressors, also suppress slx5Δ, cdc4-1, doa1Δ, hir2Δ, and cdc7-4 GALCSE4 SDL. Reduced dosage of H4 leads to defects in sumoylation and reduced mislocalization of overexpressed Cse4, which contributes to suppression of CIN when Cse4 is overexpressed. We determined that the hhf1-20, cse4-102, and cse4-111 mutants, which are defective in the Cse4-H4 interaction, also exhibit reduced sumoylation of Cse4 and do not display psh1Δ GALCSE4 SDL. In summary, we have identified genes that contribute to the mislocalization of overexpressed Cse4 and defined a role for the gene dosage of H4 in facilitating Cse4 sumoylation and mislocalization to noncentromeric regions, leading to CIN when Cse4 is overexpressed.
The use of expanded carrier screening of gamete donors
Authors: Payne Molly R , Skytte Anne-Bine , Harper Joyce C
Published: March 2021

STUDY QUESTION

What are the sperm and egg donor rejection rates after expanded carrier screening (ECS)?

SUMMARY ANSWER

Using an ECS panel looking at 46/47 genes, 17.6% of donors were rejected.

WHAT IS KNOWN ALREADY

The use of ECS is becoming commonplace in assisted reproductive technology, including testing of egg and sperm donors. Most national guidelines recommend rejection of donors if they are carriers of a genetic disease. If the use of ECS increases, there will be a decline in the number of donors available.

STUDY DESIGN, SIZE, DURATION

A review of the current preconception ECS panels available to donors was carried out through an online search. The genetic testing results of donors from Cryos International were analysed to determine how many were rejected on the basis of the ECS.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data on gamete donors and their carrier status was provided by Cryos International, who screen donors using their own bespoke ECS panel. The ECS panels identified through the review were compared to the Cryos International panel and data.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 16 companies and 42 associated ECS panels were reviewed. There were a total of 2673 unique disorders covered by the panels examined, with a mean of 329 disorders screened. None of these disorders were common to all panels. Cryos International screen 46 disorders in males and 47 in females. From 883 candidate donors, 17.6% (155/883) were rejected based on their ECS result. Carriers of alpha-thalassaemia represented the largest proportion of those rejected (19.4%, 30/155), then spinal muscular atrophy (15.5%, 24/155) and cystic fibrosis (14.8%, 23/155).

LIMITATIONS, REASONS FOR CAUTION

Panel information was found on company websites and may not have been accurate.

WIDER IMPLICATIONS OF THE FINDINGS

This study highlights the need for consistent EU regulations and guidelines that allow genetic matching of gamete donors to their recipients, preventing the need to reject donors who are known carriers. A larger ECS panel would be most beneficial; however, this would not be viable without matching of donors and recipients.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was obtained. J.C.H. is the founder of Global Women Connected, a platform to discuss women’s health issues and the Embryology and PGD Academy, who deliver education in clinical embryology. She has been paid to give a lecture by Cryos in 2019. A-B.S. is an employee of Cryos International.

TRIAL REGISTRATION NUMBER

N/A
Invasive Bacterial Vaccine-Preventable Disease Surveillance: Successes and Lessons Learned in Bangladesh for a Sustainable Path Forward
Authors: Saha Senjuti , Saha Samir K
Published: March 2021

We have made considerable progress in setting and scaling up surveillance systems to drive evidence-based policy decisions, but the recent epidemics highlight that current systems are not optimally designed. Good surveillance systems should be coordinated, comprehensive, and adaptive. They should generate data in real time for immediate analysis and intervention, whether for endemic diseases or potential epidemics. Such systems are especially needed in low-resource settings where disease burden is the highest, but tracking systems are the weakest here due to competing priorities and constraints on available resources. In this article, using the examples of 3 large, and mostly successful, infectious disease surveillance studies in Bangladesh, we identify 2 core limitations—the pathogen bias and the vaccine bias—in the way current surveillance programs are designed for low-resource settings. We highlight the strengths of the current Global Invasive Bacterial Vaccine Preventable Disease Surveillance Network of the World Health Organization and present case studies from Bangladesh to illustrate how this surveillance platform can be leveraged to overcome its limitations. Finally, we propose a set of criteria for building a comprehensive infectious disease surveillance system with the hope of encouraging current systems to use the limited resources as optimally as possible to generate the maximum amount of knowledge.
Clinical efficacy and safety of remdesivir in patients with COVID-19: a systematic review and network meta-analysis of randomized controlled trials
Authors: Lai Chih-Cheng , Chen Chao-Hsien , Wang Cheng-Yi , Chen Kuang-Hung , Wang Ya-Hui , Hsueh Po-Ren
Published: March 2021

Objectives

We performed a systematic review and network meta-analysis of randomized controlled trials (RCTs) to provide updated information regarding the clinical efficacy of remdesivir in treating coronavirus disease 2019 (COVID-19).

Methods

PubMed, Embase, Cochrane Library, clinical trial registries of ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform were searched for relevant articles published up to 18 November 2020.

Results

Five RCTs, including 13 544 patients, were included in this meta-analysis. Among them, 3839 and 391 patients were assigned to the 10 day and 5 day remdesivir regimens, respectively. Patients receiving 5 day remdesivir therapy presented greater clinical improvement than those in the control group [OR = 1.68 (95% CI 1.18–2.40)], with no significant difference observed between the 10 day and placebo groups [OR = 1.23 (95% CI 0.90–1.68)]. Patients receiving remdesivir revealed a greater likelihood of discharge [10 day remdesivir versus control: OR = 1.32 (95% CI 1.09–1.60); 5 day remdesivir versus control: OR = 1.73 (95% CI 1.28–2.35)] and recovery [10 day remdesivir versus control: OR = 1.29 (95% CI 1.03–1.60); 5 day remdesivir versus control: OR = 1.80 (95% CI 1.31–2.48)] than those in the control group. In contrast, no mortality benefit was observed following remdesivir therapy. Furthermore, no significant association was observed between remdesivir treatment and an increased risk of adverse events.

Conclusions

Remdesivir can help improve the clinical outcome of hospitalized patients with COVID-19 and a 5 day regimen, instead of a 10 day regimen, may be sufficient for treatment. Moreover, remdesivir appears as tolerable as other comparators or placebo.
Antimalarial primaquine for spinal sensory and motor blockade in rats
Authors: Chou An-Kuo , Chiu Chong-Chi , Wang Jhi-Joung , Chen Yu-Wen , Hung Ching-Hsia
Published: March 2021

Objectives

The purpose of the experiment was to estimate whether intrathecal antimalarial drugs could provoke spinal block, and their comparison with lidocaine.

Methods

Rats were intrathecally administrated with antimalarial agents (primaquine, chloroquine, hydroxychloroquine and amodiaquine) and lidocaine, and neurobehavioural examinations (nociception, proprioception and motor function) were assessed; n = 8 per group. One-way and two-way analysis of variance were designed to analyse data.

Key findings

At a concentration of 20 mM, primaquine (0.46 mg/rat) exhibited the longest duration and the most potent effect of nociceptive, proprioceptive and motor blockade (P < 0.01) among five drugs, whereas the other antimalarial drugs displayed a lesser or similar potency of spinal blockade compared with lidocaine (0.29 mg/rat). In dose-dependent studies, primaquine was more potent (P < 0.01) than lidocaine for spinal block. At ED25, ED50 and ED75 equipotent doses, primaquine produced a greater duration of spinal motor, proprioceptive and nociceptive blockade when compared with lidocaine (P < 0.01).

Conclusions

Primaquine, chloroquine, hydroxychloroquine and amodiaquine produced spinal blockade. Primaquine was more potent and displayed a prolonged life of local anaesthetic effect compared with lidocaine, whereas the other antimalarial drugs displayed a lesser or similar potency compared with lidocaine.
Massively calcified aneurysm of the anterior communicating artery: an unsuccessful clipping attempt followed by successful pCONus2-assisted coil occlusion
Authors: Haj Amer , Schmidt Nils Ole , Wendl Christina , Schebesch Karl-Michael
Published: March 2021

We report the unique case of a 67-year-old female patient with an incidentally discovered massively calcified aneurysm of the anterior communicating artery. After interdisciplinary discussion, we decided to attempt clipping the aneurysm because interventional therapy did not seem feasible and anchoring a stent would also have been difficult because of the morphology of the aneurysm. The clipping attempt was unsuccessful because of the aneurysm’s massive calcification with strong adherence to the sphenoid planum. The aneurysm was then successfully occluded using pCONus 2-assisted coiling. We illustrate this and consecutive procedures, and we reviewed the literature on aneurysm calcification.
Surrogate Born Children’s Access to Information About Their Origins
Authors: O’Callaghan Elaine
Published: March 2021

This article considers the rights of surrogate born children to access information about their origins. Proposals for reform in the UK and Ireland are discussed, and it is argued that there needs to be a greater consideration of children’s rights law in this context. In particular, it is observed that restricting children’s access to identifying information until they are 18 years old must be reconsidered. There is a myriad of reasons for this, not least obligations under international human rights law, as well as evidence from research which demonstrates that children should be informed about their origins and birth story at a young age. The introduction of a minimum age limit under the age of 18 years, to access identifying information, as is evident in some jurisdictions, is considered. Children’s access to information in the context of international surrogacy arrangements is also discussed. It is concluded that legislators should seek to take a children’s rights approach, and facilitate children in accessing information about their origins during their childhood.
A corpus-based approach to explore the stylistic peculiarity of Koji Uno’s postwar works
Authors: Liu Xueqin , Jin Mingzhe
Published: March 2021

This research aims to investigate the peculiarity of the postwar works of Koji Uno, a prominent Japanese littérateur, through a quantitative comparative analysis with his contemporaries. Uno’s writing career was twice subjected to interruption, first due to mental illness and second due to World War II. Literary critics hold the view that the unique writing style of Uno’s postwar works makes him easily distinguishable from other writers. However, it is difficult to understand the specificity of his writing without drawing comparison with his contemporaries. Therefore, this study conducted a comparative analysis to clarify the unique lexical and syntactic elements of Uno’s postwar works. As revealed by the analytical results, the most significant factors distinguishing Uno’s works from that of other writers comprise the exceptional application of conjunctions and symbols. Uno’s work shows more reliance on explicit conjunctions to connect sentences. He also inserted parenthetical annotations starting with such conjunctions as ‘つまり’ (in brief) and ‘あるいは’ (or) to enhance the readability of his sentences. Uno also employed punctuation marks, especially commas, to minimize the length of the element between punctuation marks.
The Alma catalogue of OB stars – II. A cross-match with Gaia DR2 and an updated map of the solar neighbourhood
Authors: Pantaleoni González M , Maíz Apellániz J , Barbá R H , Reed B Cameron
Published: March 2021

We cross-match the Alma catalogue of OB stars with Gaia DR2 astrometry and photometry as a first step towards producing a clean sample of massive stars in the solar neighbourhood with a high degree of completeness. We analyse the resulting colour–absolute magnitude diagram to divide our sample into categories and compare extinction estimates from two sources, finding problems with both of them. The distances obtained with three different priors are found to have few differences among them, indicating that Gaia DR2 distances are robust. An analysis of the 3D distribution of massive stars in the solar neighbourhood is presented. We show that a kinematically distinct structure we dub the Cepheus spur extends from the Orion–Cygnus spiral arm towards the Perseus arm and is located above the Galactic mid-plane, likely being related to the recently discovered Radcliffe wave. We propose that this corrugation pattern in the Galactic disc may be responsible for the recent enhanced star formation at its crests and troughs. We also discuss our plans to extend this work in the immediate future.
Galaxy formation in the brane world I: overview and first results
Authors: Hernández-Aguayo César , Arnold Christian , Li Baojiu , Baugh Carlton M
Published: March 2021

We carry out ‘full-physics’ hydrodynamical simulations of galaxy formation in the normal-branch Dvali–Gabadadze–Porrati (nDGP) braneworld model using a new modified version of the arepo code and the IllustrisTNG galaxy formation model. We simulate two nDGP models (N5 and N1) that represent, respectively, weak and moderate departures from general relativity (GR), in boxes of sizes $62$ and $25\, h^{-1}{\rm Mpc}$ using 2 × 5123 dark matter particles and initial gas cells. This allows us to explore, for the first time, the impact of baryonic physics on galactic scales in braneworld models of modified gravity and to make predictions on the stellar content of dark matter haloes and galaxy evolution through cosmic time in these models. We find significant differences between the GR and nDGP models in the power spectra and correlation functions of gas, stars and dark matter of up to ∼25 per cent on large scales. Similar to their impact in the standard cosmological model (Λ cold dark matter), baryonic effects can have a significant influence over the clustering of the overall matter distribution, with a sign that depends on scale. Studying the degeneracy between modified gravity and galactic feedback in these models, we find that these two physical effects on matter clustering can be cleanly disentangled, allowing for a method to accurately predict the matter power spectrum with baryonic effects included, without having to run hydrodynamical simulations. Depending on the braneworld model, we find differences compared with GR of up to ∼15 per cent in galaxy properties such as the stellar-to-halo-mass ratio, galaxy stellar mass function, gas fraction, and star formation rate density. The amplitude of the fifth force is reduced by the presence of baryons in the very inner part of haloes, but this reduction quickly becomes negligible above ∼0.1 times the halo radius.
Subaru Hyper Suprime-Cam excavates colossal over- and underdense structures over 360 deg2 out toz= 1
Authors: Shimakawa Rhythm , Higuchi Yuichi , Shirasaki Masato , Tanaka Masayuki , Lin Yen-Ting , Hayashi Masao , Momose Rieko , Lee Chien-Hsiu , Kusakabe Haruka , Kodama Tadayuki , Yamamoto Naoaki
Published: March 2021

Subaru Strategic Program with the Hyper-Suprime Cam (HSC-SSP) has proven to be successful with its extremely wide area coverage in past years. Taking advantages of this feature, we report initial results from exploration and research of expansive over- and underdense structures at z = 0.3–1 based on the second Public Data Release where optical 5-band photometric data for ∼ eight million sources with i < 23 mag are available over ∼360 deg2. We not only confirm known superclusters but also find candidates of titanic over- and underdense regions out to z = 1. The mock data analysis suggests that the density peaks would involve one or more massive dark matter haloes (>1014 M⊙) of the redshift, and the density troughs tend to be empty of massive haloes over >10 comoving Mpc. Besides, the density peaks and troughs at z ≲ 0.6 are in part identified as positive and negative weak lensing signals respectively, in mean tangential shear profiles, showing a good agreement with those inferred from the full-sky weak lensing simulation. The coming extensive spectroscopic surveys will be able to resolve these colossal structures in 3D space. The number density information over the entire survey field is available as grid-point data on the website of the HSC-SSP data release (https://hsc.mtk.nao.ac.jp/ssp/data-release/).
Arrokoth’s necklace
Authors: Katz J I , Wang S
Published: March 2021

Fly-by images of (486958) Arrokoth (Ultima Thule, 2014 MU69) show a comparatively bright ‘necklace’ in the neck, or cleft, between its two lobes, in contrast to its generally low albedo. We suggest that the necklace may be the result of thermally controlled ice deposition. The necklace is found in the most (orbitally averaged) shaded part of the surface. It may consist of clean, high albedo, ice condensed from vapour sublimed by dirty, low albedo, ice elsewhere; ice accumulates where the maximum temperatures are the lowest. Ammonia and propane have the necessary mesovolatile vapour pressure. Surrounding gas in the proto-Solar system would facilitate redeposition of molecules sublimed by warmer parts of the surface into the cleft, as well as smoothing the surface and explaining, by hydrodynamic drag, Arrokoth’s slow (compared to its break-up rate) rotation. Alternatively, a layer of hoarfrost thick enough ($\gtrsim 0.1\, \mu$) to have a high albedo could have formed more recently.
Dust temperature in ALMA [C ii]-detected high-z galaxies
Authors: Sommovigo L , Ferrara A , Carniani S , Zanella A , Pallottini A , Gallerani S , Vallini L
Published: March 2021

At redshift z > 5, the far-infrared (FIR) continuum spectra of main-sequence galaxies are sparsely sampled, often with a single data point. The dust temperature Td,SED, thus has to be assumed in the FIR continuum fitting. This introduces large uncertainties regarding the derived dust mass (Md), FIR luminosity, and obscured fraction of the star formation rate. These are crucial quantities to quantify the effect of dust obscuration in high-z galaxies. To overcome observation limitations, we introduce a new method that combines dust continuum information with the overlying [C $\scriptstyle \rm II$] 158 µm line emission. By breaking the Md–Td,SED degeneracy, with our method, we can reliably constrain the dust temperature with a single observation at 158 µm. This method can be applied to all Atacama Large Millimeter Array (ALMA) and NOEMA [C $\scriptstyle \rm II$] observations, and exploited in ALMA Large Programs such as ALPINE and REBELS targeting [C $\scriptstyle \rm II$] emitters at high-z. We also provide a physical interpretation of the empirical relation recently found between molecular gas mass and [C $\scriptstyle \rm II$] luminosity. We derive an analogous relation linking the total gas surface density and [C $\scriptstyle \rm II$] surface brightness. By combining the two, we predict the cosmic evolution of the surface density ratio $\Sigma _{\rm H_2} / \Sigma _{\rm gas}$. We find that $\Sigma _{\rm H_2} / \Sigma _{\rm gas}$ slowly increases with redshift, which is compatible with current observations at 0 < z < 4.
What determines the structure of short gamma-ray burst jets?
Authors: Urrutia Gerardo , De Colle Fabio , Murguia-Berthier Ariadna , Ramirez-Ruiz Enrico
Published: March 2021

The discovery of GRB 170817A, the first unambiguous off-axis short gamma-ray burst (sGRB) arising from a neutron star merger, has challenged our understanding of the angular structure of relativistic jets. Studies of the jet propagation usually assume that the jet is ejected from the central engine with a top-hat structure and its final structure, which determines the observed light curve and spectra, is primarily regulated by the interaction with the nearby environment. However, jets are expected to be produced with a structure that is more complex than a simple top-hat, as shown by global accretion simulations. We present numerical simulations of sGRBs launched with a wide range of initial structures, durations, and luminosities. We follow the jet interaction with the merger remnant wind and compute its final structure at distances ≳1011 cm from the central engine. We show that the final jet structure, as well as the resulting afterglow emission, depends strongly on the initial structure of the jet, its luminosity, and duration. While the initial structure of the jet is preserved for long-lasting sGRBs, it is strongly modified for jets barely making their way through the wind. This illustrates the importance of combining the results of global simulations with propagation studies in order to better predict the expected afterglow signatures from neutron star mergers. Structured jets provide a reasonable description of the GRB 170817A afterglow emission with an off-axis angle θobs ≈ 22.5°.
Modelling the UV/optical continuum time-lags in AGN
Authors: Kammoun E S , Papadakis I E , Dovčiak M
Published: March 2021

Thermal reverberation in accretion discs of active galactic nuclei is thought to be the reason of the continuum UV/optical time lags seen in these sources. Recently, we studied thermal reverberation of a standard Novikov-Thorne accretion disc illuminated by an X–ray point-like source, and we derived an analytic prescription for the time lags as function of wavelength. In this work, we use this analytic function to fit the time-lags spectra of seven Seyferts, that have been intensively monitored, in many wave-bands, in the last few years. We find that thermal reverberation can explain the observed UV/optical time lags in all these sources. Contrary to previous claims, the magnitude of the observed UV/optical time-lags is exactly as expected in the case of a standard accretion disc in the lamp-post geometry, given the black hole mass and the accretion rate estimates for the objects we study. We derive estimates of the disc accretion rates and corona height for a non-spinning and a maximally spinning black hole scenarios. We also find that the modelling of the continuum optical/UV time-lags can be used to estimate the black hole spin, when combined with additional information. We also find that the model under-predicts the observed X–ray to UV time-lags, but this difference is probably due to the broad X-ray auto-correlation function of these sources.
Magnetic field generation from PBH distributions
Authors: Araya I J , Rubio M E , San Martín M , Stasyszyn F A , Padilla N D , Magaña J , Sureda J
Published: March 2021

We introduce a statistical method for estimating magnetic field fluctuations generated from primordial black hole (PBH) populations. To that end, we consider monochromatic and extended Press–Schechter PBH mass functions, such that each constituent is capable of producing its own magnetic field due to some given physical mechanism. Assuming a linear correlation between magnetic field fluctuations and matter overdensities, our estimates depend on the mass function, the physical field generation mechanism by each PBH constituent, and the characteristic PBH separation. After computing the power spectrum of magnetic field fluctuations, we apply our formalism to study the plausibility that two particular field generation mechanisms could have given rise to the expected seed fields according to current observational constraints. The first mechanism is the Biermann battery and the second one is due to the accretion of magnetic monopoles at PBH formation, constituting magnetic PBHs. Our results show that, for monochromatic distributions, it does not seem to be possible to generate sufficiently intense seed fields in any of the two field generation mechanisms. For extended distributions, it is also not possible to generate the required seed field by only assuming a Biermann battery mechanism. In fact, we report an average seed field by this mechanism of about 10−47 G, at z = 20. For the case of magnetic monopoles, we instead assume that the seed values from the literature are achieved and calculate the necessary number density of monopoles. In this case, we obtain values that are below the upper limits from current constraints.
Molecular contrails – triggered contraction by passages of massive objects through molecular clouds
Authors: Li Guang-Xing , Shi Xun
Published: March 2021

We study the effects of passages of compact objects such as stars, star clusters, and black holes through molecular clouds, and propose that the gravitational interaction between the compact object and the ambient gas can lead to the formation of thin and collimated features made of dense gas, which we call ‘molecular contrails’. Supercritical contrails can collapse further leading to triggered star formation. The width of a molecular contrail is determined by the mass and velocity of the compact object and the velocity dispersion of the ambient molecular medium. Under typical conditions in the Milky Way, passages of stellar-mass objects lead to the formation of width $d\gtrsim 0.01\,\,\rm {pc}$ contrails, and passages of star clusters lead to the formation of $d\gtrsim 1\,\,\rm {pc}$ contrails. We present a few molecular contrail candidates from both categories identified from ALMA 1.3 mm continuum observations of star-forming regions and the 13CO(1-0) map from the Galactic Ring Survey, respectively. The contrails represent an overlooked channel where stars and gas in the Galactic disc interact to form structures. They also present a potential way of detecting dark compact objects in the Milky Way.
Predicting images for the dynamics of stellar clusters (π-DOC): a deep learning framework to predict mass, distance, and age of globular clusters
Authors: Chardin Jonathan , Bianchini Paolo
Published: March 2021

Dynamical mass estimates of simple systems such as globular clusters (GCs) still suffer from up to a factor of 2 uncertainty. This is primarily due to the oversimplifications of standard dynamical models that often neglect the effects of the long-term evolution of GCs. Here, we introduce a new approach to measure the dynamical properties of GCs, based on the combination of a deep-learning framework and the large amount of data from direct N-body simulations. Our algorithm, π-DOC (Predicting Images for the Dynamics Of stellar Clusters) is composed of two convolutional networks, trained to learn the non-trivial transformation between an observed GC luminosity map and its associated mass distribution, age, and distance. The training set is made of V-band luminosity and mass maps constructed as mock observations from N-body simulations. The tests on π-DOC demonstrate that we can predict the mass distribution with a mean error per pixel of 27 per cent, and the age and distance with an accuracy of 1.5 Gyr and 6 kpc, respectively. In turn, we recover the shape of the mass-to-light profile and its global value with a mean error of 12 per cent, which implies that we efficiently trace mass segregation. A preliminary comparison with observations indicates that our algorithm is able to predict the dynamical properties of GCs within the limits of the training set. These encouraging results demonstrate that our deep-learning framework and its forward modelling approach can offer a rapid and adaptable tool competitive with standard dynamical models.
A two-step gravitational cascade for the fragmentation of self-gravitating discs
Authors: Brucy Noé , Hennebelle Patrick
Published: March 2021

Self-gravitating discs are believed to play an important role in astrophysics in particular regarding the star and planet formation process. In this context, discs subject to an idealized cooling process, characterized by a cooling time-scale β expressed in unit of orbital time-scale, have been extensively studied. We take advantage of the Riemann solver and the 3D Godunov scheme implemented in the code Ramses to perform high-resolution simulations, complementing previous studies that have used smoothed particle hydrodynamics (SPH) or 2D grid codes. We observe that the critical value of β for which the disc fragments is consistent with most previous results, and is not well converged with resolution. By studying the probability density function of the fluctuations of the column density (Σ-PDF), we argue that there is no strict separation between the fragmented and the unfragmented regimes but rather a smooth transition with the probability of apparition of fragments steadily diminishing as the cooling becomes less effective. We find that the high column density part of the Σ-PDF follows a simple power law whose slope turns out to be proportional to β and we propose an explanation based on the balance between cooling and heating through gravitational stress. Our explanation suggests that a more efficient cooling requires more heating implying a larger fraction of dense material which, in the absence of characteristic scales, results in a shallower scale-free power law. We propose that the gravitational cascade proceeds in two steps, first the formation of a dense filamentary spiral pattern through a sequence of quasi-static equilibrium triggered by the viscous transport of angular momentum, and second the collapse alongside these filaments that eventually results in the formation of bounded fragments.
A study of the long-term activity of five intermediate polars with accretion discs
Authors: Šimon Vojtěch
Published: March 2021

Intermediate polars (IPs) are cataclysmic variables with mildly magnetized white dwarfs (WDs). This analysis of the long-term optical activity of five examples of IPs with accretion discs used data from the Catalina Real-time Transient Survey, Digital Access to a Sky Century @ Harvard (DASCH) and the American Association of Variable Star Observers (AAVSO). It is shown that each of these IPs had their most preferred value of absolute magnitude Mopt, even if it significantly varied on the superorbital time-scale. The values of Mopt of these IPs were in the zone of thermal-viscous instability (TVI) of the disc most of the time. The properties of a series of outbursts of V426 Oph can be explained by an intermittently operating TVI. The activity of TV Col and DW Cnc is interpreted as caused by a gradually variable mass inflow rate from the secondary to a cool disc. The mass transfer rate from the secondary varied on a well-determined time-scale. It is shown that Mopt of EI UMa, close to the peaks of outbursts of non-magnetic dwarf novae, fluctuated on the time-scale of days; it also produced short flares, ascribed to the bursts of matter from the donor. HY Leo, with a presumably cool disc, fluctuated between its high and low states. A temporary brightening from an extended low state is ascribed to a short, intense burst of matter from the donor to the remaining cool disc or torus.
Return migration and self-employment: is there a ‘jack-of-all-trades’ effect?
Authors: Mahé Clotilde
Published: March 2021

With reference to Lazear’s jack-of-all-trades hypothesis, I examine whether migrants are more likely to be self-employed upon return because of the diverse work experience they gained abroad. The endogeneity between migration, human capital investment, and self-employment is addressed by exploiting exogenous cohort and regional variation in the decision to migrate in the context of Egypt, and parental labour market information. Return migrants’ higher propensity to be self-employed is shown to proceed from participating in significantly more occupations over their work history than non-migrants. In line with Lazear’s framework, estimates confirm that entrepreneurship can be learnt, and that exposure to multiple occupations matters for entrepreneurship.
Energy Policy in Japan
Authors: Hughes Llewelyn
Published: March 2021

This chapter examines major changes in Japan’s energy system, focusing on the period since the March 11 Fukushima disaster. There remain numerous opportunities to describe and explain how politics is affecting the incremental but radical changes in the Japanese energy system. While the Japanese government continues to place concerns about security of energy supplies at the center of energy policy, climate change is the defining challenge for the Japanese government, and energy use is at the center of Japan’s greenhouse gas emissions profile. This chapter offers a sectoral analysis of the direction and degree of change evident across nuclear power, renewable energy, coal, electrification, and transport. A key question is the extent to which the politics of energy is democratizing, understood both in terms of an increased ability to influence siting choices for large centralized energy assets and directly owning or using sources of distributed renewable energy such as rooftop solar power.
Organ Transplantation
Authors: Cayon-De Las Cuevas Joaquin , Orentlicher David
Published: March 2021

This chapter examines the process of organ transplantation, which is different from other therapies in a very important way—there is a persistent and large gap between the need for transplants and the availability of organs. Many more patients need a transplant than can receive one. The shortage of organs is compounded by enormous variability in the donation and transplant activity of different countries. These disparities in access reflect factors that are highly complex and sensitive, including legal, organizational, and cultural. Still, as indicated, the shortage of organs is a global problem that affects all countries, both those that have implemented effective donation and transplant systems and those that still lack them. Accordingly, in the regulation of organ transplantation, considerable attention is paid to strategies for increasing the organ supply and policies for allocating the organs that are available.