bluuebunny/crossref_metadata_2025 huggingface dataset:
Fidelity, Feasibility and Adaptation of a Family Planning Intervention for Young Women in Zimbabwe: Provider Perspectives and Experiences
Authors: Mavodza Constancia V. , Bernays Sarah , Mackworth-Young Constance R. S. , Nyamwanza Rangarirayi , Nzombe Portia , Dauya Ethel , Chikwari Chido Dziva , Tembo Mandikudza , Apollo Tsitsi , Mugurungi Owen , Madzima Bernard , Nguwo Dadirai , Ferrand Rashida Abbas , Busza Joanna
Published: March 2023

The CHIEDZA (Community-based Interventions to improve HIV outcomes in youth: a cluster randomised trial in Zimbabwe) trial evaluated an integrated package of HIV and sexual and reproductive health services for young people aged 16–24 years in Zimbabwe. The family planning component aimed to improve access to information, services, and contraceptives delivered by trained youth-friendly providers within a community-based setting for young women. Responsively adapting the intervention was a part of the intervention design’s rationale. We investigated the factors influencing implementation fidelity, quality, and feasibility using provider experiences and perspectives. We conducted provider interviews (N = 42), non-participant (N = 18), and participant observation (N = 30) of intervention activities. The data was analyzed thematically. CHIEDZA providers were receptive to providing the family planning intervention, but contexts outside of the intervention created challenges to the intervention’s fidelity. Strategic adaptations were required to ensure service quality within a youth-friendly context. These adaptations strengthened service delivery but also resulted in longer wait times, more frequent visits, and variability of Long-Acting Reversible contraceptives (LARCS) provision which depended on target-driven programming by partner organization. This study was a practical example of how tracking adaptations is vital within process evaluation methods in implementation science. Anticipating that changes will occur is a necessary pre-condition of strong evaluations and tracking adaptations ensures that lessons on feasibility of design, contextual factors, and health system factors are responded to during implementation and can improve quality. Some contextual factors are unpredictable, and implementation should be viewed as a dynamic process where responsive adaptations are necessary, and fidelity is not static.

Trial registration ClinicalTrials.gov Identifier: NCT03719521.
The Art of International Law
Authors: Charlesworth Hilary
Published: March 2023

International lawyers study international law primarily through its written texts—treaties, official documents, judgments, and scholarly works. Critical to being an international lawyer, it seems, is access to the written word, whether in hard copy or online. Indeed, as Jesse Hohmann observes, “the production of text can come to feel like the very purpose of international law.”
Experimental study on the combined effects of patch density and elongation on wake structure behind a rectangular porous patch
Authors: Zhang Yuan-Heng , Duan Huan-Feng , Yan Xu-Feng , Stocchino Alessandro
Published: March 2023

This paper presents an experimental study on how both variable solid volume fractions and aspect ratios (length/width) of a centre-channel rectangular porous patch under aligned configuration of rigid and emergent stems impact the flow behaviour and wake structure. This study forms an essential extension to the existing fundamentals and knowledge on this topic. Through rigorous experimental tests by velocity measurement and dye visualization, the aspect ratio, rarely addressed before, is confirmed to play a critical role. Vortex street, unable to be triggered under a low solid volume fraction, however, can be generated by elongating the patch (increasing the aspect ratio). The key reason is that patch elongation promotes the generation of the wake vortex street by producing a relatively high transverse velocity gradient in the wake region. Meanwhile, Kelvin–Helmholtz vortex streets are triggered along the two patch lateral edges, re-increasing the in-patch velocity and imposing contributions to the wake vortex streets generation. By scaling the characteristic velocity (at the wake vortex initiation position and patch trailing edge) and solid volume fraction with the patch aspect ratio, three non-dimensional threshold maps can be established to express the combined effects of the solid volume fraction and aspect ratio on the initiation of the wake vortex street. They could be alternatively used for theoretical analysis and implementation on wake formation and structure subject to parameter availability.
Has maternal sensitivity been comprehensively investigated in sub-Saharan Africa? A narrative scoping review
Authors: Prag A. , Donald K.A. , Weldon E. , Halligan S.L. , Stein D.J. , Malcolm-Smith S.
Published: March 2023

Child development is strongly influenced by maternal characteristics. Maternal sensitivity, as well as risks to and outcomes of sensitive maternal style, are well studied in industrialised western contexts, but it is unclear if this is the case for other contexts. Sub-Saharan Africa has been subjected to and continues to negotiate socio-economic and psychological sequelae of colonial and race-based politics: exploring the nature and outcomes of early caregiver input in such challenging conditions is imperative. This scoping review thus aims to 1) evaluate the nature and extent of quantified observational assessments of dyadic interactions, with a focus on maternal sensitivity, in Sub-Saharan Africa and 2) ascertain which risk and outcome factors have been examined in relation to maternal sensitivity. Study quality and cross-cultural appropriateness will also be considered. The search using expanded search terms yielded 20 papers –four characterizing maternal sensitivity or style, eight examining maternal sensitivity in relation to risks and outcomes, and eight intervention studies examining efforts to improve maternal sensitivity. Most research was conducted in South Africa – only seven studies were conducted in four other countries. Researchers used a wide array of coding schemes, mostly developed in the west. Ten studies made some adaptations to measures. Language issues and cultural considerations were often not explicitly addressed. Taken together, very limited research on this important topic exists. For the work that does exist, questions around westernized assumptions, language, and appropriateness of measures remain. Substantially more research, informed by both culturally flexible conceptualizations and methodological rigour, is required.
STRICT REGULARITY FOR -COCYCLES OF FINITE GROUPS
Authors: HIGGS R. J.
Published: March 2023

Let
$\alpha $
be a complex-valued
$2$
-cocycle of a finite group
$G.$
A new concept of strict
$\alpha $
-regularity is introduced and its basic properties are investigated. To illustrate the potential use of this concept, a new proof is offered to show that the number of orbits of G under its action on the set of complex-valued irreducible
$\alpha _N$
-characters of N equals the number of
$\alpha $
-regular conjugacy classes of G contained in
$N,$
where N is a normal subgroup of
$G.$
HALL SUBGROUPS AND -COCYCLE REGULARITY
Authors: HIGGS R. J.
Published: March 2023

Let H be a subgroup of a finite group G and let
$\alpha $
be a complex-valued
$2$
-cocycle of
$G.$
Conditions are found to ensure there exists a nontrivial element of H that is
$\alpha $
-regular in
$G.$
However, a new result is established allowing a prime by prime analysis of the Sylow subgroups of
$C_G(x)$
to determine the
$\alpha $
-regularity of a given
$x\in G.$
In particular, this result implies that every
$\alpha _H$
-regular element of a normal Hall subgroup H is
$\alpha $
-regular in
$G.$
Effect of pre-grazing herbage mass and post-grazing sward height on herbage production and intake and performance of suckler-bred steers within a weanling-to-beef production system
Authors: Doyle P. R. , McGee M. , Moloney A. P. , Kelly A. K. , O'Riordan E. G.
Published: March 2023

The current study investigated the effects of pre-grazing herbage mass (PGHM, 1500 or 2500 kg dry matter (DM)/ha) and post-grazing sward height (PGSH, 4 or 6 cm) on herbage production and its nutritive value and DM intake, grazing behaviour and growth of Charolais steers (n = 96; 12 months of age; 396 ± 19.0 kg) during a 222-day grazing season, and the subsequent effect of an indoor finishing diet (grass silage alone or supplemented with concentrates) for 146 days, on performance and carcass traits. Steers were assigned to one of 12 grazing groups and group was assigned to a 2 (PGHM) × 2 (PGSH) factorial arrangement of treatments. At the end of the grazing season, live-weight was 16 kg heavier for PGHM-1500 than PGHM-2500 and 34 kg heavier for PGSH-6 than PGSH-4. After indoor finishing, there was no difference in carcass weight between PGHM treatments, but PGSH-6 had a 19 kg heavier carcass than PGSH-4. Herbage production was 881 and 517 kg DM/ha greater for PGHM-2500 than PGHM-1500 and for PGSH-4 than PGSH-6, respectively. Grazing stocking rate did not differ between PGHM treatments but PGSH-4 carried 1.35 more steers/ha than PGSH-6. Supplementing concentrates during the indoor period increased carcass weight (42 kg) and fat score (2.10 units). In conclusion, grazing to 6 rather than 4 cm, increased individual carcass weight but not carcass weight gain/ha. Compared to PGHM-2500, grazing PGHM-1500 increased steer live-weight gain at pasture, but did not affect carcass weight following indoor finishing.
‘Stand up like a Taiwanese!’: PRC coercion and public preferences for resistance
Authors: Chong Ja Ian , Huang David W. F. , Wu Wen-Chin
Published: March 2023

Taiwan's opposition to PRC demands such as acceptance of the ‘92 Consensus’ and ‘One Country, Two Systems’ formula since 2016 has invited a series of retaliatory measures from Beijing, designed to coerce Taiwan into compliance. Given the stark asymmetry in economic size, military capability, and diplomatic status, Taiwan provides a case for studying coercive diplomacy that takes the form of threats to punish. Material differences suggest that Taiwan should capitulate, and ‘cheap talk’ theses expect PRC threats to have no discernible effect, while balance of threat arguments expect resolve. In this article, we use the survey data collected in the 2016, 2019, and 2020 rounds of the Taiwan National Security Study to examine how Taiwanese respond to China's intensifying and expanding threats. Our paper identifies four strategies that the public sees as responses to PRC coercion: isolation, bandwagon with China, balance against China by allying with the USA and Japan, and hedge by deepening economic ties with China while aligning with the USA and Japan against China. We show that the popular support for balancing against China rises as PRC coercion grows and Taiwanese citizens increasingly perceive China to be a threat. Our findings imply that citizens in a liberal democracy can develop the will to pushback against pressure from an authoritarian regime despite sharp asymmetries in capabilities and material limitations.
Explaining fluctuations in the Thrift Savings Fund daily balance at U.S. treasury
Authors: Skidmore Mark , Alvayay Torrejón Camila , Pare David
Published: March 2023

This article examines the G-Fund, which is one of the five funds in the federal government employee retirement Thrift Savings Plan. The G-Fund is held as internal debt by the U.S. Department of Treasury. Our examination shows that the fund balance is exclusively composed of 1-day notes that are redeemed/reissued every business day, generating $55 trillion in annual debt reissuance. We also show that the fund balance drops substantially as resources are transferred to the general fund when the government is constrained by a debt ceiling and returns to pre-constraint levels when the ceiling is expanded/suspended.
Effect of a single dose of intravenous ketamine on the wish to hasten death in palliative care: A case report in advanced cancer
Authors: Decazes Esther , Rigal Oliver , Clatot Florian
Published: March 2023

Objectives

The suffering experienced by some patients at the end of their lives can lead to a wish to hasten death (WTHD). It is sometimes an existential suffering, refractory to palliative care even if well conducted, which leads to this desire. Since several years, in psychiatry, the rapid anti-suicidal effects of a single injection of ketamine have been proven. WTHD and suicidal ideation have similarities. The injection of a single dose of ketamine could have an efficiency on the desire to hasten death.

Methods

We report the case of a woman with advanced breast cancer expressing a WTHD, treated by ketamine.

Results

A 78-year-old woman expressed a WTHD (request for euthanasia) because of existential suffering following a loss of autonomy related to cancer. The suicide item was 4 on the Montgomery–Åsberg Depression Rating Scale (MADRS). She had no associated pain or depression. A single dose of intravenous ketamine 1 mg/kg over 40 min plus 1 mg of midazolam was injected. She had no adverse effects. From D1 post-injection to D3, the WTHD disappeared completely with a MADRS suicide item at 0. At D5, the WTHD started to reappear, and at D6, the previous speech was completely back.

Significance of the results

These results suggest an effect of ketamine on WTHD. This opens up the possibility of treating existential suffering at the end of life. The optimal dosage of this treatment would have to be determined as well as a maintenance of efficacy scheme.
Rapid necrosis: Implications of environmental conditions and plant growth stage on 2,4-D resistance and effect of other auxinic herbicides in Sumatran fleabane (Conyza sumatrensis)
Authors: Angonese Paula Sinigaglia , de Queiroz Andrew Rerison Silva , Angonese Liana Sinigaglia , Machado Filipi Mesquita , Napier Richard , Markus Catarine , Delatorre Carla A. , Merotto Aldo
Published: March 2023

Resistant plants of Sumatran fleabane with unusual rapid necrosis (RN) symptoms after application of 2,4-D were characterized in previous studies. Field observations indicated variability in the occurrence of the RN caused by 2,4-D, but the causes of the variation are unknown. This study aimed to investigate the effect of environmental conditions, plant growth stage, and simultaneous and sequential herbicide mixtures with other auxin mimics on the occurrence of RN caused by 2,4-D. Application at temperature of 12 C delayed the symptoms and decreased the intensity of the RN but still resulted in plant survival to 2,4-D. The absence of light after herbicide application caused a slight delay in the symptoms, but the production of hydrogen peroxide and the size of the necrosed area were not affected by the light treatments before and after 2,4-D application. Changes in plant photosynthesis through inhibiting photosystem II do not prevent the occurrence of RN symptoms. The auxinic herbicides dicamba, triclopyr, and halauxifen-methyl do not cause RN symptoms and are effective at controlling the resistant biotype when applied without 2,4-D, but the effectiveness of these herbicides was reduced when sprayed on the resistant biotype either together, 4 h, or 24 h after 2,4-D. The RN phenotype does not occur for dicamba and triclopyr, even in advanced plant growth stages and high doses on the resistant biotype. The herbicides dicamba and triclopyr effectively controlled resistant plants, especially when sprayed at the initial growth stages. The results of this study identify environmental effects, plant development effects, and herbicide interactions that interfere with the occurrence of RN symptoms caused by 2,4-D in Sumatran fleabane. These data provide insights about the mechanisms behind the RN symptoms caused by 2,4-D and are important for identifying the causes of variability of the herbicide symptomology and performance under experimental and field conditions.
Validation of a German Version of the Stress Overload Scale and Comparison of Different Time Frames in the Instructions
Authors: Haehner Peter , Pfeifer Lena Sophie , Jahre Lisa Maria , Luhmann Maike , Wolf Oliver T. , Frach Leonard
Published: March 2023

Abstract: Introduction: The Stress Overload Scale (SOS; Amirkhan, 2012 , 2018 ) was introduced as a two-factorial self-report measure of stress to overcome limitations of other scales. Methods: We developed a German translation of the SOS and validated it in addition to a short version and an extra-short version. Furthermore, we tested whether manipulating the time frame introduced as retention interval in the instructions affected its psychometric properties. Results: Using two independent age-heterogeneous convenience samples ( Ntotal = 1,239), we found good psychometric properties for a modified German short version of the SOS-S (SOS-S-G) and a new extra-short version (SOS-XS-G), but not for the German long version of the SOS. Moreover, manipulating the time frame of the SOS did not affect its psychometric quality. Discussion The SOS enriches the repertoire of self-report measures of stress as it captures the nonpathological core facets of stress in line with theoretical stress conceptualizations.
Community‐Engaged Assessment of Soil Lead Contamination in Atlanta Urban Growing Spaces
Authors: Peters Samuel J. W. , Warner Sydney M. , Saikawa Eri , Ryan P. Barry , Panuwet Parinya , Barr Dana B. , D'Souza Priya E. , Frank Gil , Hernandez Rosario , Alvarado Taranji , Hines Arthur , Theal Chris
Published: March 2023

Urban agriculture is emerging as a method to improve food security and public health in cities across the United States. However, an increased risk of exposure to heavy metals and metalloids (HMM) exists through interaction with contaminated soil. Community‐engaged research (CEnR) is one method that can promote the inclusion of all partners when studying exposures such as HMM in soil. Researchers and community gardeners co‐designed this study to measure the concentrations of lead (Pb), using X‐Ray Fluorescence (XRF) verified with Inductively Coupled Plasma‐Mass Spectrometry (ICP‐MS) in soils from 19 urban agricultural and residential sites in the Westside of Atlanta and three rural sites in Georgia. Seventeen other HMM were measured but not included in this study, because they did not pose risks to the community comparable to elevated Pb levels. Pb concentrations were compared to the Environmental Protection Agency (EPA)'s regional screening levels (RSLs) for residential soil and the University of Georgia (UGA) extension service's low‐risk levels (LRLs) for agriculture. Soils from the majority of sites had levels below EPA RSLs for Pb, yet above the UGA LRL. However, soil Pb concentrations were three times higher than the EPA RSL on some sites that contained metal refining waste or slag. Our findings led to direct action by local and federal government agencies to initiate the cleanup of slag residue. Studies involving exposures to communities should engage those affected throughout the process for maximum impact.
Properties of Flapping Current Sheet of the Martian Magnetotail
Authors: Zhang Chi , Rong Zhaojin , Zhang Lulu , Gao Jiawei , Shi Zhen , Klinger Lucy , Shen Chao , Wei Yong
Published: March 2023

Knowing the properties of the Martian magnetotail flapping waves is critical to understand the dynamics of the Martian induced magnetosphere. Based on the measurements by Mars Atmosphere and Volatile EvolutioN and a newly developed method, we provide the first quantitative study of Martian magnetotail flapping waves in comparison with Earth's magnetotail flapping waves. We found that the period of Martian magnetotail flapping waves ranges from ∼50 to ∼250 s. The estimated average wave amplitude is ∼380 km, and the wavelength is ∼1,100 km. The estimated propagation speed ranges from ∼3 to ∼30 km/s, which is about a third of that of Earth's magnetotail flapping waves, and the speed declines with the increase of the current sheet thickness. Intriguingly, we found that the flapping waves with shorter periods, or lower wavelengths, can propagate faster, showing similar dispersive signatures as that found in the Earth's magnetotail. Our results demonstrate that the fluctuated field energy carried by flapping waves within unit time along unit magnetotail length is one order higher than that of Earth's flapping waves, as normalized by the magnetic energy of planetary magnetotail. Thus, in comparison with Earth's magnetotail, the flapping waves of Martian induced magnetotail would play a more important role in affecting the magnetotail dynamics.
Super-reflector enabled by non-interleaved spin-momentum-multiplexed metasurface
Authors: Xu He-Xiu , Hu Guangwei , Kong Xianghong , Shao Yanzhang , Genevet Patrice , Qiu Cheng-Wei
Published: March 2023

Electromagnetic wave multiplexing, especially for that occurring at different incidences (spatial-frequency multiplexing), is pivotal for ultrathin multifunctional interfaces and high-capacity information processing and communication. It is yet extremely challenging based on passive and compact wave elements, since the wave excitation and scattering channels are exclusively coupled through gradient phases and hence momentum matching condition at the interface. Here, we propose a spin-momentum multiplexed paradigm called a super-reflector enabling on-demand control of both retroreflections and anomalous reflections using a non-interleaved single-celled metasurface. By multiplexing four channels connecting two spin states excited onto each input of three spatial frequencies, a total of twelve channels are engineered, among which three are retroreflected channels and the residual are anomalous reflection ones. Our compound multiplexed super-reflector allows five degrees of freedom in circular polarization Jones' matrix, approaching the intrinsic upper limit of such planar metasurface. The concept has been experimentally verified by a proof-of-concept super-reflector at microwave frequency, showcasing twelve reflected beams and a high efficiency exceeding 90.6% defined as the ratio of reflected power to incidence for each channel beam. Our strategy opens a new avenue for angle multiplexing and angle-resolved metadevices toward the capacity limit of 2D planar Jones’ matrix.
Imatinib blocks tyrosine phosphorylation of Smad4 and restores TGF-β growth-suppressive signaling in BCR-ABL1-positive leukemia
Authors: Wang Lijing , Gu Shuchen , Chen Fenfang , Yu Yi , Cao Jin , Li Xinran , Gao Chun , Chen Yanzhen , Yuan Shuchong , Liu Xia , Qin Jun , Zhao Bin , Xu Pinglong , Liang Tingbo , Tong Hongyan , Lin Xia , Feng Xin-Hua
Published: March 2023

Loss of TGF-β-mediated growth suppression is a major contributor to the development of cancers, best exemplified by loss-of-function mutations in genes encoding components of the TGF-β signaling pathway in colorectal and pancreatic cancers. Alternatively, gain-of-function oncogene mutations can also disrupt antiproliferative TGF-β signaling. However, the molecular mechanisms underlying oncogene-induced modulation of TGF-β signaling have not been extensively investigated. Here, we show that the oncogenic BCR-ABL1 of chronic myelogenous leukemia (CML) and the cellular ABL1 tyrosine kinases phosphorylate and inactivate Smad4 to block antiproliferative TGF-β signaling. Mechanistically, phosphorylation of Smad4 at Tyr195, Tyr301, and Tyr322 in the linker region interferes with its binding to the transcription co-activator p300/CBP, thereby blocking the ability of Smad4 to activate the expression of cyclin-dependent kinase (CDK) inhibitors and induce cell cycle arrest. In contrast, the inhibition of BCR-ABL1 kinase with Imatinib prevented Smad4 tyrosine phosphorylation and re-sensitized CML cells to TGF-β-induced antiproliferative and pro-apoptotic responses. Furthermore, expression of phosphorylation-site-mutated Y195F/Y301F/Y322F mutant of Smad4 in Smad4-null CML cells enhanced antiproliferative responses to TGF-β, whereas the phosphorylation-mimicking Y195E/Y301E/Y322E mutant interfered with TGF-β signaling and enhanced the in vivo growth of CML cells. These findings demonstrate the direct role of BCR-ABL1 tyrosine kinase in suppressing TGF-β signaling in CML and explain how Imatinib-targeted therapy restored beneficial TGF-β anti-growth responses.
Occlusal records in the production of mounted study casts for tooth wear planning and management
Authors: Cowan Callum
Published: March 2023

This article forms part of a series looking at management of patients with tooth wear. Articulated study casts can be essential in assisting the clinician to plan and communicate proposed treatment to the dental technician and patient. Their production is often seen as straightforward, but a lack of attention to detail can quickly lead to articulated casts that do not replicate the patient clinical presentation. This in turn will lead to inaccurate planning and potentially a suboptimal treatment outcome. This article discusses a collection of the clinical records needed to produce accurate articulated study casts, which can be utilised for tooth wear planning. It also aims to present the evidence base for the recommendations outlined.
Gastrointestinal conditions related to tooth wear
Authors: Howard John P. , Howard Laura J. , Geraghty Joe , Leven A. Johanna , Ashley Martin
Published: March 2023

Gastro-oesophageal reflux disease (GORD) is a relatively common condition that occurs in adults and less commonly in children. It develops when the reflux of stomach contents into the oesophagus causes troublesome symptoms and/or complications. Signs and symptoms include heartburn, retrosternal discomfort, epigastric pain and hoarseness, dental erosion, chronic cough, burning mouth syndrome, halitosis and laryngitis. A proportion of patients will, however, have silent reflux. Strongly associated risk factors include family history, age, hiatus hernia, obesity and neurological conditions, such as cerebral palsy. There are different treatment options which may be considered for GORD, consisting of conservative, medical and surgical therapy. Dentists should be aware of the symptoms of GORD and dental signs of intrinsic erosion indicative of possible GORD so that they can question patients about this and, if appropriate, initiate a referral to a general medical practitioner.
The rhythmic coupling of Egr-1 and Cidea regulates age-related metabolic dysfunction in the liver of male mice
Authors: Wu Jing , Bu Dandan , Wang Haiquan , Shen Di , Chong Danyang , Zhang Tongyu , Tao Weiwei , Zhao Mengfei , Zhao Yue , Fang Lei , Li Peng , Xue Bin , Li Chao-Jun
Published: March 2023

The liver lipid metabolism of older individuals canbecome impaired and the circadian rhythm of genes involved in lipid metabolism is also disturbed. Although the link between metabolism and circadian rhythms is already recognized, how these processes are decoupled in liver during aging is still largely unknown. Here, we show that the circadian rhythm for the transcription factor Egr-1 expression is shifted forward with age in male mice. Egr-1 deletion accelerates liver age-related metabolic dysfunction, which associates with increased triglyceride accumulation, disruption of the opposite rhythmic coupling of Egr-1 and Cidea (Cell Death Inducing DFFA Like Effector A) at the transcriptional level and large lipid droplet formation. Importantly, adjustment of the central clock with light via a 4-hour forward shift in 6-month-old mice, leads to recovery the rhythm shift of Egr-1 during aging and largely ameliorated liver metabolic dysfunction. All our collected data suggest that liver Egr-1 might integrate the central and peripheral rhythms and regulate metabolic homeostasis in the liver.
Marine ecosystem shifts with deglacial sea-ice loss inferred from ancient DNA shotgun sequencing
Authors: Zimmermann Heike H. , Stoof-Leichsenring Kathleen R. , Dinkel Viktor , Harms Lars , Schulte Luise , Hütt Marc-Thorsten , Nürnberg Dirk , Tiedemann Ralf , Herzschuh Ulrike
Published: March 2023

Sea ice is a key factor for the functioning and services provided by polar marine ecosystems. However, ecosystem responses to sea-ice loss are largely unknown because time-series data are lacking. Here, we use shotgun metagenomics of marine sedimentary ancient DNA off Kamchatka (Western Bering Sea) covering the last ~20,000 years. We traced shifts from a sea ice-adapted late-glacial ecosystem, characterized by diatoms, copepods, and codfish to an ice-free Holocene characterized by cyanobacteria, salmon, and herring. By providing information about marine ecosystem dynamics across a broad taxonomic spectrum, our data show that ancient DNA will be an important new tool in identifying long-term ecosystem responses to climate transitions for improvements of ocean and cryosphere risk assessments. We conclude that continuing sea-ice decline on the northern Bering Sea shelf might impact on carbon export and disrupt benthic food supply and could allow for a northward expansion of salmon and Pacific herring.
The critical role of ultra-low-energy vibrations in the relaxation dynamics of molecular qubits
Authors: Garlatti E. , Albino A. , Chicco S. , Nguyen V. H. A. , Santanni F. , Paolasini L. , Mazzoli C. , Caciuffo R. , Totti F. , Santini P. , Sessoli R. , Lunghi A. , Carretta S.
Published: March 2023

Improving the performance of molecular qubits is a fundamental milestone towards unleashing the power of molecular magnetism in the second quantum revolution. Taming spin relaxation and decoherence due to vibrations is crucial to reach this milestone, but this is hindered by our lack of understanding on the nature of vibrations and their coupling to spins. Here we propose a synergistic approach to study a prototypical molecular qubit. It combines inelastic X-ray scattering to measure phonon dispersions along the main symmetry directions of the crystal and spin dynamics simulations based on DFT. We show that the canonical Debye picture of lattice dynamics breaks down and that intra-molecular vibrations with very-low energies of 1-2 meV are largely responsible for spin relaxation up to ambient temperature. We identify the origin of these modes, thus providing a rationale for improving spin coherence. The power and flexibility of our approach open new avenues for the investigation of magnetic molecules with the potential of removing roadblocks toward their use in quantum devices.
Curvature induces active velocity waves in rotating spherical tissues
Authors: Brandstätter Tom , Brückner David B. , Han Yu Long , Alert Ricard , Guo Ming , Broedersz Chase P.
Published: March 2023

The multicellular organization of diverse systems, including embryos, intestines, and tumors relies on coordinated cell migration in curved environments. In these settings, cells establish supracellular patterns of motion, including collective rotation and invasion. While such collective modes have been studied extensively in flat systems, the consequences of geometrical and topological constraints on collective migration in curved systems are largely unknown. Here, we discover a collective mode of cell migration in rotating spherical tissues manifesting as a propagating single-wavelength velocity wave. This wave is accompanied by an apparently incompressible supracellular flow pattern featuring topological defects as dictated by the spherical topology. Using a minimal active particle model, we reveal that this collective mode arises from the effect of curvature on the active flocking behavior of a cell layer confined to a spherical surface. Our results thus identify curvature-induced velocity waves as a mode of collective cell migration, impacting the dynamical organization of 3D curved tissues.
Field-linear anomalous Hall effect and Berry curvature induced by spin chirality in the kagome antiferromagnet Mn3Sn
Authors: Li Xiaokang , Koo Jahyun , Zhu Zengwei , Behnia Kamran , Yan Binghai
Published: March 2023

During the past two decades, it has been established that a non-trivial electron wave-function topology generates an anomalous Hall effect (AHE), which shows itself as a Hall conductivity non-linear in magnetic field. Here, we report on an unprecedented case of field-linear AHE. In Mn3Sn, a kagome magnet, the out-of-plane Hall response, which shows an abrupt jump, was discovered to be a case of AHE. We find now that the in-plane Hall response, which is perfectly linear in magnetic field, is set by the Berry curvature of the wavefunction. The amplitude of the Hall response and its concomitant Nernst signal exceed by far what is expected in the semiclassical picture. We argue that magnetic field induces out-of-plane spin canting and thereafter gives rise to nontrivial spin chirality on the kagome lattice. In band structure, we find that the spin chirality modifies the topology by gapping out Weyl nodal lines unknown before, accounting for the AHE observed. Our work reveals intriguing unification of real-space Berry phase from spin chirality and momentum-space Berry curvature in a kagome material.
Many-body bound states and induced interactions of charged impurities in a bosonic bath
Authors: Astrakharchik Grigory E. , Ardila Luis A. Peña , Jachymski Krzysztof , Negretti Antonio
Published: March 2023

Induced interactions and bound states of charge carriers immersed in a quantum medium are crucial for the investigation of quantum transport. Ultracold atom-ion systems can provide a convenient platform for studying this problem. Here, we investigate the static properties of one and two ionic impurities in a bosonic bath using quantum Monte Carlo methods. We identify three bipolaronic regimes depending on the strength of the atom-ion potential and the number of its two-body bound states: a perturbative regime resembling the situation of a pair of neutral impurities, a non-perturbative regime that loses the quasi-particle character of the former, and a many-body bound state regime that can arise only in the presence of a bound state in the two-body potential. We further reveal strong bath-induced interactions between the two ionic polarons. Our findings show that numerical simulations are indispensable for describing highly correlated impurity models.
Polar meron-antimeron networks in strained and twisted bilayers
Authors: Bennett Daniel , Chaudhary Gaurav , Slager Robert-Jan , Bousquet Eric , Ghosez Philippe
Published: March 2023

Out-of-plane polar domain structures have recently been discovered in strained and twisted bilayers of inversion symmetry broken systems such as hexagonal boron nitride. Here we show that this symmetry breaking also gives rise to an in-plane component of polarization, and the form of the total polarization is determined purely from symmetry considerations. The in-plane component of the polarization makes the polar domains in strained and twisted bilayers topologically non-trivial, forming a network of merons and antimerons (half-skyrmions and half-antiskyrmions). For twisted systems, the merons are of Bloch type whereas for strained systems they are of Néel type. We propose that the polar domains in strained or twisted bilayers may serve as a platform for exploring topological physics in layered materials and discuss how control over topological phases and phase transitions may be achieved in such systems.
Aiolos represses CD4+ T cell cytotoxic programming via reciprocal regulation of TFH transcription factors and IL-2 sensitivity
Authors: Read Kaitlin A. , Jones Devin M. , Pokhrel Srijana , Hales Emily D. S. , Varkey Aditi , Tuazon Jasmine A. , Eisele Caprice D. , Abdouni Omar , Saadey Abbey , Leonard Melissa R. , Warren Robert T. , Powell Michael D. , Boss Jeremy M. , Hemann Emily A. , Yount Jacob S. , Xin Gang , Ghoneim Hazem E. , Lio Chan-Wang J. , Freud Aharon G. , Collins Patrick L. , Oestreich Kenneth J.
Published: March 2023

During intracellular infection, T follicular helper (TFH) and T helper 1 (TH1) cells promote humoral and cell-mediated responses, respectively. Another subset, CD4-cytotoxic T lymphocytes (CD4-CTLs), eliminate infected cells via functions typically associated with CD8+ T cells. The mechanisms underlying differentiation of these populations are incompletely understood. Here, we identify the transcription factor Aiolos as a reciprocal regulator of TFH and CD4-CTL programming. We find that Aiolos deficiency results in downregulation of key TFH transcription factors, and consequently reduced TFH differentiation and antibody production, during influenza virus infection. Conversely, CD4-CTL programming is elevated, including enhanced Eomes and cytolytic molecule expression. We further demonstrate that Aiolos deficiency allows for enhanced IL-2 sensitivity and increased STAT5 association with CD4-CTL gene targets, including Eomes, effector molecules, and IL2Ra. Thus, our collective findings identify Aiolos as a pivotal regulator of CD4-CTL and TFH programming and highlight its potential as a target for manipulating CD4+ T cell responses.
A hybrid Monte Carlo study of bond-stretching electron–phonon interactions and charge order in BaBiO3
Authors: Cohen-Stead Benjamin , Barros Kipton , Scalettar Richard , Johnston Steven
Published: March 2023

The relationship between electron–phonon (e-ph) interactions and charge-density-wave (CDW) order in the bismuthate family of high-temperature superconductors remains unresolved. We address this question using nonperturbative hybrid Monte Carlo calculations for the parent compound BaBiO3. Our model includes the Bi 6sand O 2pσorbitals and coupling to the Bi-O bond-stretching branch of optical phonons via modulations of the Bi-O hopping integral. We simulate three-dimensional clusters of up to 4000 orbitals, with input model parameters taken from ab initio electronic structure calculations and a phonon energy ℏΩ0 = 60 meV. Our results demonstrate that the coupling to the bond-stretching modes is sufficient to reproduce the CDW transition in this system, despite a relatively small dimensionless coupling. We also find that the transition deviates from the weak-coupling Peierls’ picture. This work demonstrates that off-diagonale-ph interactions in orbital space are vital in establishing the bismuthate phase diagram.
In vitro hair follicle growth model for drug testing
Authors: Kageyama Tatsuto , Miyata Hikaru , Seo Jieun , Nanmo Ayaka , Fukuda Junji
Published: March 2023

In vitro models of human hair follicle-like tissue could be fundamental tools to better understand hair follicle morphogenesis and hair drug screening. During prenatal development and postnatal cyclic hair regeneration, hair follicle morphogenesis is triggered by reciprocal interactions and the organization of the epithelial and mesenchymal cell populations. Given this mechanism, we developed an approach to induce hair peg-like sprouting in organoid cultures composed of epithelial and mesenchymal cells. Human fetal/adult epithelial and mesenchymal cells were cultured in a medium supplemented with a low concentration of either Matrigel or collagen I. These extracellular matrices significantly enhanced the self-organization capabilities of the epithelial and mesenchymal cells, resulting in spherical aggregation and subsequent hair peg-like sprouting. The length of the hair peg sprouting and associated gene expression significantly increased in the presence of a well-known hair drug, minoxidil. This approach may be beneficial for testing hair growth-promoting drug candidates.
Recurrent activity in neuronal avalanches
Authors: Salners Tyler , Avila Karina E. , Nicholson Benjamin , Myers Christopher R. , Beggs John , Dahmen Karin A.
Published: March 2023

A new statistical analysis of large neuronal avalanches observed in mouse and rat brain tissues reveals a substantial degree of recurrent activity and cyclic patterns of activation not seen in smaller avalanches. To explain these observations, we adapted a model of structural weakening in materials. In this model, dynamical weakening of neuron firing thresholds closely replicates experimental avalanche size distributions, firing number distributions, and patterns of cyclic activity. This agreement between model and data suggests that a mechanism like dynamical weakening plays a key role in recurrent activity found in large neuronal avalanches. We expect these results to illuminate the causes and dynamics of large avalanches, like those seen in seizures.
An imperfect spectrum sensing-based multi-hop clustering routing protocol for cognitive radio sensor networks
Authors: Wang Jihong , Liu Chang
Published: March 2023

Multi-hop clustering routing protocols are potential solutions to achieve effective and energy-efficient data delivery in cognitive radio sensor networks (CRSNs). Current clustering routing protocols for CRSNs generally assume perfect spectrum sensing, i.e., false alarm and missed detection are ignored, which may result in collisions with primary users and transmission failure or constrained spectrum usage. To alleviate the impact of imperfect spectrum sensing on network performance, an imperfect spectrum sensing-based multi-hop clustering routing protocol (ISSMCRP) is proposed for CRSNs in this paper. Cluster head (CH) and relay selection criteria are defined based on detection level function of available channels to help select CHs and relays with high spectrum sensing capability. Idle detection accuracy-based intra-cluster and inter-cluster channel selection criterion is proposed to promote successful intra-cluster and inter-cluster data delivery. In addition, control overhead introduced by CHs selection and cluster formation is strictly controlled, and reasonable cluster radii are set to manage the range of control information exchange, so as to reduce the energy consumption caused by control overhead. Simulation results show that compared with the existing clustering routing protocols for CRSNs, ISSMCRP gains obvious advantages in expanding the network lifespan and enhancing the network surveillance capability.
LNA blockers for improved amplification selectivity
Authors: Prout Jaime , Tian Michael , Palladino Alicia , Wright Jason , Thompson John F.
Published: March 2023

LNA-containing oligonucleotides bind DNA more tightly than standard DNA, so they can interact with targeted sequences and affect multiple processes. When a desired DNA is present at low concentrations relative to nearly identical undesired DNAs, LNAs can block amplification of unwanted DNAs. Using a short rAAV and synthetic DNA sequence as a model, we studied the length, number, and positioning of LNA bases to improve blocker effectiveness. Oligonucleotides 18–24 bases long with LNAs at every other position were most effective. Highly degenerate targets were used to characterize the impact of mismatches on blocking. Mismatches at LNA ends had little impact on blocking activity. Single and double mismatches were tolerated with longer blockers, especially if the mismatches were near LNA ends. Shorter LNAs were more selective, with > 1 mismatch preventing effective blocking. Neither the strand to which a blocker bound nor the distance between the blocker and priming sites greatly impacted blocking efficiency. We used these findings to design blockers of wild-type DNA versus the single-base A1AT PiZ allele. Blockers are most specific when the mismatch is located away from the LNA 5′ end. Pairs of partially overlapping blockers on opposite strands with a centrally-located mismatch have maximal activity and specificity.
Tracheoesophageal fistula treated with magnetic compression technique in canines
Authors: Li Yixing , Zhang Miaomiao , Liu Peinan , Zhang Zhixuan , Zhang Hanzhi , Lyu Yi , Yan Xiaopeng
Published: March 2023

There are various surgical methods for tracheoesophageal fistula; however, there is presently no unified standard. Based on the magnetic compression technique, we designed a novel method for the treatment of tracheoesophageal fistula. The purpose of this study was to verify its feasibility in an animal experiment. Six beagle dogs underwent surgical repair after constructing a tracheoesophageal fistula model. After the tracheal and esophageal spaces were freed during the operation, two magnets were used to clamp the fistula. The operation time, intraoperative blood loss, postoperative complications, and wound healing were monitored. Samples were obtained 14 days after the operation, and fistula repair was observed. The tracheoesophageal fistula repair operation was successfully completed for all six beagles. The average operation time was 23.67 ± 4.50 min. The average intraoperative blood loss was less than 10 mL. One dog had a postoperative wound infection, and the rest had no postoperative complications. The wound healed well. In all dogs, after specimen collection, it was observed that the fistula was successfully closed and the mucosal layer was smooth and flat. Histological observation showed that the anastomosis was slightly inflamed, the mucosal layer and surrounding tissues were arranged neatly, and the structure was slightly disordered. Magnetic compression technique can be effectively used to repair tracheoesophageal fistula, shorten the operation time, and simplify the operation procedure, and thus, it has the potential for clinical application.
Evidence for cultural differences in affect during mother–infant interactions
Authors: Abu Salih Miada , Abargil Maayan , Badarneh Saja , klein Selle Nathalie , Irani Merav , Atzil Shir
Published: March 2023

Maternal care is considered a universal and even cross-species set of typical behaviors, which are necessary to determine the social development of children. In humans, most research on mother–infant bonding is based on Western cultures and conducted in European and American countries. Thus, it is still unknown which aspects of mother–infant behaviors are universal and which vary with culture. Here we test whether typical mother–infant behaviors of affect-communication and affect-regulation are equally represented during spontaneous interaction in Palestinian-Arab and Jewish cultures. 30 Palestinian-Arab and 43 Jewish mother–infant dyads were recruited and videotaped. Using AffectRegulation Coding System (ARCS), we behaviorally analyzed the second-by-second display of valence and arousal in each participant and calculated the dynamic patterns of affect co-regulation. The results show that Palestinian-Arab infants express more positive valence than Jewish infants and that Palestinian-Arab mothers express higher arousal compared to Jewish mothers. Moreover, we found culturally-distinct strategies to regulate the infant: increased arousal in Palestinian-Arab dyads and increased mutual affective match in Jewish dyads. Such cross-cultural differences in affect indicate that basic features of emotion that are often considered universal are differentially represented in different cultures. Affect communication and regulation patterns can be transmitted across generations in early-life socialization with caregivers.
Hybridization of papain molecules and DNA-wrapped single-walled carbon nanotubes evaluated by atomic force microscopy in fluids
Authors: Kitamura Masaki , Umemura Kazuo
Published: March 2023

Although various conjugates of single-walled carbon nanotubes (SWNTs) and biomolecules, such as nanobiosensors and nanobiodevices, have been reported, the conjugation of papain and SWNTs have not been reported because of the formation of unexpected aggregates. In this study, atomic force microscopy (AFM) in liquid was used to investigate the interactions between papain and DNA-wrapped SWNTs (DNA–SWNTs) at two different pH values (pH 3.0 and 10.5). The direct AFM observation of the mixture of papain and DNA–SWNTs confirmed the aggregation of papain molecules with DNA–SWNTs in the buffer solutions. The numerous and non-uniform adsorption of papain molecules onto DNA–SWNTs was more pronounced at pH 3.0 than that at pH 10.5. Furthermore, thick conjugates appeared when papain and DNA–SWNTs were simultaneously mixed. The near-infrared photoluminescence spectra of the SWNTs drastically changed when the papain molecules were injected into the DNA–SWNT suspension at pH 3.0. Thus, the regulation of electrostatic interactions is a key aspect in preparing optimal conjugates of papain and DNA–SWNTs. Furthermore, although previous papers reported AFM images of dried samples, this study demonstrates the potential of AFM in liquid in evaluating individual bioconjugates of SWNTs.