Thin Line Research Articles

Measurement of interstellar extinction for classical T Tauri stars using far-UV H_2 line fluxes

Understanding the interstellar and potentially circumstellar extinction in the sight lines of classical T Tauri stars is an important ingredient for constructing reliable spectral energy distributions, which catalyze protoplanetary disk chemistry, for example. Therefore, some attempts of measuring $A_ V $ toward individual stars have been made using partly different wavelength regimes and different underlying assumptions. We used strong lines of Lyalpha fluorescent H$_ and derived the extinction based on the assumption of optically thin transitions. We investigated a sample of 72 classical T Tauri stars observed with the Hubble Space Telescope in the framework of the ULLYSES program. We computed $A_V$ and $R_V$ values for the 34 objects with sufficient data quality and an additionally $A_V$ value for the canonical $R_V=3.1$ value. Our results agree largely with values obtained from optical data. Moreover, we confirm the degeneracy between $A_ V $ and $R_ V $ and present possibilities to break this. Finally, we discuss whether the assumption of optical thin lines is valid.

Pedagogical uses of AI tools: reflection on a case study

Academic writing is central to assessment in UK universities (Goodfellow, 2005). The emergence of easily accessible generative artificial intelligence (GenAI) tools took the sector by storm, with some voices raising critical concerns about academic integrity and the de-skilling of writing, while others pointed to the developmental and time-saving opportunities these tools can offer (OpenAI, 2023; UNESCO, 2023). This presentation reflected on the author’s experience of designing and delivering a workshop on ‘Introduction to proofreading techniques using AI tools’. The workshop was developed as part of a broader Academic Innovation Project designed to support the developmental and ethical use of GenAI tools by student writers at one institution in line with internal and emerging sector policies (such as Russell Group, 2023). The presentation outlined the workshop plan, including learning outcomes and sample activities, alongside highlighting some of the challenges experienced during the design process. It also offered critical insights into the delivery and impact on student learning, with reference to the author’s reflections as well as student engagement and feedback. A major challenge that can be transferable to other pedagogical uses of GenAI tools was the difficulty in navigating the thin line between, on the one hand, encouraging workshop participants to experiment with a range of tools in a safe learning space and, on the other hand, raising their awareness of the ethical implications and potential risks that over-reliance on such tools may pose to their learning, particularly the development of their academic writing.

Worn-Down Nails: A Rare Entity

This case report discusses a rare condition known as bidet nail syndrome, characterised by worn-down triangular nails resulting from repetitive rubbing against bidet porcelain during genital area cleaning. The patient, a 35-year-old male pharmacist, presented with splitting and redness in the nail plates of both big toes, attributed to tight and anteriorly covered shoes. Clinical examination revealed a triangular area of nail thinning with slight redness and a thin brown line along the edges. Dermoscopic findings indicated nail bed reddening, enlarged capillaries and small areas of bleeding corresponding to nail thinning. The provisional diagnosis included worn-down nails, lacquer nails and onychoteiromania, with the final confirmation of worn-down nails. The patient showed significant improvement after changing footwear, emphasising the importance of lifestyle modifications. The bidet nail syndrome, initially described in 1999, is associated with chronic scratching or manual labour, with susceptibility to nail plate damage varying among individuals. This case underscores the need for dermatologists to recognise and differentiate worn-down nails from similar conditions, enabling accurate diagnosis and avoiding unnecessary treatments. Overall, bidet nail syndrome is a self-limiting condition, emphasising the importance of a thorough medical history for effective management.

Serological profile of voluntary blood donors in a blood bank of tertiary health care centre- An institution-based study

Background: The safe transfusion of blood facilities is an essential component of an efficient, excellent healthcare sector. Unsafe blood transfusions can be a cause of transfusion-transmitted infections and can be lethal. The present study was conducted to find out the seroprevalence of HBsAg, HCV, HIV, malarial parasites, and syphilis in voluntary blood donors in a tertiary care center. Materials and methods: This prospective study was conducted at the blood bank of the Shri Mahant Indiresh Hospital, Dehradun. 16413 samples from all blood donations were screened for HBsAg, HCV, HIV 1 and 2, malaria, and syphilis. Samples were collected in vacutainers at the time of blood donation and screened for HIV 1and2, HBsAg, and HCV using the fourth-generation enzyme-linked immunosorbent assay technique. Syphilis was tested by Treponema antibodies using the VITROS Syphilis TPA Reagent Pack. Malaria was tested by pan malaria card, monoclonal anti-pan specific parasite lactate dehydrogenase antibody conjugated to colloidal gold, and another monoclonal anti-pan specific parasite lactate dehydrogenase antibody immobilized on a nitrocellulose strip in a thin line. Results: Out of 16413 blood donors 342(2.1%) were found to be seropositive and 16071 (97.9%) were found to be seronegative. The total number of donors, who were found positive for HBsAg/Anti HCV was 1 (0.3%). Out of the seropositive cases, HBsAg, HCV, HIV, and Syphilis infections constituted 28.9%, 27.5, 14.6, and 28.7% cases respectively. Conclusions: There is a need for the development and implementation of stringent donor selection and sensitive screening tests to reduce the risk of acquiring transfusion-transmitted illnesses.

Regimes of Self-Presentation and Digital Street Credibility: How Urban Youth Negotiate Online and Offline Visibility

AbstractDrawing on a study of how young people in Switzerland appropriate urban public space, this article explores what we term “regimes of self-presentation” among youth in both online and offline spaces. We address issues of privacy and power that help shape such regimes by applying an expanded notion of street credibility that encompasses digital practices. Our concept of “digital street credibility” recognizes how, in today’s world, any social or cultural practices engaged in by youth have two potential types of audiences. One is physically present, consisting of other users of urban public space. The second audience is media-based, consisting of people with access to live or prerecorded digital content captured on smartphones and shared on social networks. This situation has forced young people to develop new and specific social conventions governing self-presentation. The article highlights the complex and perilous nature of visibility management. Where privacy and power relations are concerned, a very thin line separates behavior that enhances an individual’s social status from actions considered “embarrassing” or “cringe.” Our results show how, in the streets as well as online, acceptable forms of visibility are determined on the basis of digital street credibility. These findings suggest a need to reconsider young people’s understanding of privacy, as it relates to their leisure activities in urban and digital spaces.

Chromospheric Mg I emission lines of pre-main-sequence stars

To reveal details of the internal structure, the relationship between chromospheric activity and the Rossby number has been extensively examined for main-sequence stars. For active pre-main-sequence (PMS) stars, it is suggested that the level of activity be assessed using optically thin emission lines, such as Mg I. We aim to detect Mg I chromospheric emission lines from PMS stars and to determine whether the chromosphere is activated by the dynamo process or by mass accretion from protoplanetary disks. We analyzed high-resolution optical spectra of $64\ $PMS stars obtained with the Very Large Telescope (VLT)/X-shooter and UVES and examined the infrared Ca II ($8542\ AA $) and Mg I ($8807\ AA $) emission lines. To detect the weak chromospheric emission lines, we determined the atmospheric parameters ($T_ eff $ and $ g$) and the degree of veiling of the PMS stars by comparing the observed spectra with photospheric model spectra. After subtracting the photospheric model spectrum from the PMS spectrum, we detected Ca II and Mg I as emission lines. The strengths of the Mg I emission lines in PMS stars with no veiling are comparable to those in zero-age main-sequence (ZAMS) stars if both types of stars have similar Rossby numbers. The Mg I emission lines in these PMS stars are thought to be formed by a dynamo process similar to that in ZAMS stars. In contrast, the Mg I emission lines in PMS stars with veiling are stronger than those in ZAMS stars. These objects are believed to have protoplanetary disks, where mass accretion generates shocks near the photosphere, heating the chromosphere. The chromosphere of PMS stars is activated not only by the dynamo process but also by mass accretion.

A thin line between consent and abuse - Reflections on sexual experiences among Swedish young adults with intellectual disabilities.

Research shows that young adults with intellectual disabilities struggle to understand the social codes embedded in sexual situations. This may lead to an incomprehension of sexual consent, or when consenting to sex may lead to abuse. This qualitative study aimed to gain an in-depth understanding of sexual experiences and perceptions about sexual consent among Swedish young adults with intellectual disabilities. The data comprise 22 semi-structured interviews with young adults aged 18-35 with intellectual disabilities, thematically analyzed using sexual script theory as a theoretical framework. Four themes emerged from the analysis: Setting the sexual scene, Sexual self-awareness, Sexual communication and the necessity of clarification and Striving for a balance. The results show that the participants had a variety of sexual experiences and challenges associated with sexual consent, but also an agency that favors sexual situations. Further research is necessary to understand the complexities of sexual consent in this population.

Puns and pain in Palestine

Ahmed Masoud’s The Shroud Maker packs a powerful punch in using the implicative potential of black comedy as a site of resistance. Masoud deploys black comedy to resist and assert control over the exploitative discourse and action against the Palestinians living in Gaza. He does this by using black humour as a tool of alienation to detach people from their trauma, break the fourth wall to make the audience complicit, as a weapon to challenge Israeli dominant discourse, and to assert Palestinian control over the war’s narrative. Dark humour walks the thin line between humour and conflict in the play where “battered by injustice, but still defiant,” the eighty-four-year-old protagonist, Hajja Souad, a shroud maker by profession, introduces trauma through humour and then tips the balance in favour of trauma. Through her offensive jokes and satiric thrust, the play confronts the desensitisation of violence against Palestinians by evoking a reaction in the audience—laughter, followed by reflection on their laughter. While the balancing act between humour and trauma is maintained, The Shroud Maker argues that humour is perhaps the most effective way of communicating and ascribing responsibility to its spectators. Ahmed Masoud puts forth an alternative way of discussing political violence and war beyond the dominant western narrative that marginalises the Palestinian voice. Relaying the tragedy of violence and culture wars through dark humour underscores the message of resistance, coping and persistence in Palestine.

(Annihilation?) or Conversion: Thought and Problematics

The paper investigates the thought of “annihilation,” its theoretical underpinnings, and the praxical overtures it posits. It investigates the how and what of annihilation: what of annihilation as a term, and what Ambedkar wanted the text Annihilation of Caste (AoC) to be. With this frame, the paper re-reads AoC to read the thin line of “conversion” that becomes the only decision, that is, to convert inevitably, by the end of the speech. The paper argues that the term “annihilation” is of Jat-Pat-Todak Mandal and not of Ambedkar’s (as is overwhelmingly assumed, even in the scholarship), although the term remains precisely important to Ambedkar in his theological Buddhistic aspirations. The paper also reads AoC as a “text of conversion” and not as a “text of annihilation.” The paper then initiates an epistemic possibility in framing Ambedkar’s caste-destruction project anew, wherein conversion and spirituality dominate the praxical scenario as against annihilation.

Significantly improved optical and radiation transmission performance of borate glasses via Tb and Yb rare earth doping

The present study was intended to present new borate glass structure with attractive properties useful for optical and radiation shielding purposes. Therefore, a novel series of B2O3-glass samples defined as: 75B2O3 – 10Li2O – (15-x-y)PbO – x(Yb2O3) – y(Tb2O3), where the corresponding oxide fractions are expressed in mol percent and x and y varied between 1 and 2 mol%, were prepared by employing the well-known melting-and-quenching technique. The structural, physical, optical, and radiation interaction qualities of the glasses were probed based on established experimental and theoretical processes. There was a thin line between the density and molar volumes of the glasses, fluctuating between 3.168 and 3.224 g/cm3 and 28.602 and 29.117 cm3/mol, respectively. All the glass samples exhibited a transparency of over 80 % in the visible range and most parts of the infrared spectrum. The analysis of the gamma photon interaction parameters showed that density and chemical composition greatly influence the shielding abilities of the glasses. The mean free paths of the studied glasses were lower than some known shielding glasses and other materials. The value of ΣR for 1Y0T, 1Y1T, 1Y2T, and 2Y1T is 0.1059, 0.1066, 0.1051, and 0.1063 cm−1, respectively. The half value layers of the glasses had almost a constant minimum value of 0.005 cm at the minimum energy (0.015 MeV) and maximum values of 7.192, 7.100, 7.152, and 7.035 cm for 1Y0T, 1Y1T, 1Y2T, and 2Y1T, respectively at 10.000 MeV. The glasses are potentially more effective for radiation shielding and also desirable where there is lack of space for thicker shield designs. The present glasses had better fast neutron moderating capacities compared to some conventional moderators. None of the studied borate glasses showed a clear performance advantage to the others in terms of absorbing electrons, protons, alpha particles and heavy carbon ions. The studied borate glasses are recommended as transparent and effective radiation protection barriers in ionizing radiation facilities.

Learning to See: Wittgenstein and Perception in Terrence Malick’s The Thin Red Line

Learning to See: Wittgenstein and Perception in Terrence Malick’s The Thin Red Line

A public grid of radiative transfer simulations for Lyman-alpha and metal lines in idealised galactic outflows

The vast majority of star-forming galaxies are surrounded by large reservoirs of gas ejected from the interstellar medium. Ultraviolet absorption and emission lines represent powerful diagnostics to constrain the cool phase of these outflows, through resonant transitions of hydrogen and metal ions. The interpretation of these observations is often remarkably difficult as it requires detailed modelling of the propagation of the continuum and emission lines in the gas. To this aim, we present a large public grid of $ 20,000$ simulated spectra that includes and five metal transitions associated with and which is accessible online. The spectra have been computed with the Monte Carlo radiative transfer code for $5,760$ idealised spherically symmetric configurations surrounding a central point source emission, and characterised by their column density, Doppler parameter, dust opacity, wind velocity, as well as various density and velocity gradients. Designed to predict and interpret and metal line profiles, our grid exhibits a wide diversity of resonant absorption and emission features, as well as fluorescent lines. We illustrate how it can help better constrain the wind properties by performing a joint modelling of observed and spectra. Using simulations and virial scaling relations, we also show that is expected to be a faithful tracer of the gas at $T 10^4-10^5$ K, even if the medium is highly ionised. While is found to probe the same range of temperatures as other metal lines merely trace cooler phases ($T 10^4$ K). As their gas opacity strongly depends on gas temperature, incident radiation field, metallicity and dust depletion, we caution that optically thin metal lines do not necessarily originate from low column densities and may not accurately probe Lyman continuum leakage.

Spurious reconstruction from brain activity: The thin line between reconstruction, classification, and hallucination

Spurious reconstruction from brain activity: The thin line between reconstruction, classification, and hallucination

Cocoa Transfer Agreements, moneylenders, public letter writers and the rise of business elites in South West Nigeria, 1986–2000

Abstract This paper focuses on the subject of the cocoa transfer agreements and the transformation of rural agrarian livelihoods in the cocoa belt of South West Nigeria under the Structural Adjustment Programme (SAP). The paper maps the trajectory and career of three dominant agricultural entrepreneurs in the cocoa produce trade in South West Nigeria during the 20th century. The paper demonstrates that while the cocoa business in Nigeria has received considerable scholarly attention, the impact of moneylenders, public letter writers (PLWs) and cocoa transfer agreements on cocoa business, rural livelihoods and entrepreneurship in the aftermath of SAP is yet to be fully investigated. Analysing the accumulative strategies and contributions of Emmanuel Akintan, Isaac Adegbuyi Akingboye and Rufus Orosundafosi to rural capital formation, the paper highlights the impacts of liberalisation policies on African rural businesses in the aftermath of SAP. The paper combines primary sources, such as oral interviews, personal observation and ethnography, with information collected from the archives, newspapers, diaries, and extant literature to analyse the dynamics of rural accumulation in the cocoa producing South West Nigeria during the 20th century. The paper argues that the acquisition of wealth and the thin line between standard procedures and clandestine deals stimulated accusations of dispossession of peasant farmers by the capitalist moneylenders and merchants in the post-SAP era.

The Thin Blue Line: Perspectives From Military Veteran Police Officers on Camaraderie and Cooperation

The Thin Blue Line: Perspectives From Military Veteran Police Officers on Camaraderie and Cooperation

Improving Multi-pixel Visual Quality of Invariant Visual Cryptography Scheme

A visual cryptography scheme (VCS) splits the secret image into several shares. Stacking a certain number of shares will reveal the secret image. The principle algorithm (deterministic algorithm) retains the size of shares, and the revealed image is at least double the size of the secret image with good visual quality. In contrast, the probabilistic algorithm has the size of the revealed image equal to that of the secret image with the noisily revealed image. Multi-pixel algorithm cast solutions for the trade off problems between the good visual quality and the non-expansion size of the revealed image. In this paper, we introduce new algorithms for multi-pixel to improve the quality of preceding algorithms, generalize the multi-pixel algorithm, provide evidence of the best form of multi-pixel, and contribute to the thin line problem.

Žižek at the Buchmesse: Evil, Cancel Culture, and the Difficulty of Diversity

This article argues that Slavoj Žižek’s provocative speech at the Frankfurt Book Fair was a political event of the first order. Described as a major scandal triggered by Žižek’s remarks on the Israel-Hamas war, the speech was much more than a deliberate provocation. It provides a window into a world that had become unhinged long before the conflict erupted anew. It offers an opportunity to observe the complex relationship between individuals, institutions, and society. It continues to be a cautionary tale that illustrates the thin line between courage and hypocrisy; and how difficult it is to practise diversity in a world gripped by the dangerous logic of evil. Thus, Žižek’s opening address transcends its immediate context because it brings us up against one of today’s defining questions: what does it mean, and what does it take, to practise diversity when facing the most divisive topics of our time?

Exploration of room temperature magnetodielectric behavior in Nd0.5Dy0.5FeO3 thin films and transmission line resonators in GHz frequency range

This study explores the room-temperature magnetodielectric (MD) and magnetoresistance (MR) properties of Nd0.5Dy0.5FeO3 thin films on n-type silicon substrates from 4 Hz to 2 MHz. The observed MD effect registers a change of ∼23 %, and the MR effect manifests a change of ∼11 % when subjected to an applied magnetic field of 2.5 T at a frequency of 177 Hz. Interestingly, the MD effect was absent at 1 T across all frequencies. However, we observed an MR of 6 % at 1 T, implying the possibility of an intrinsic MD effect or the co-existence of both intrinsic and extrinsic contributions to the MD effect. To comprehensively gauge the dielectric properties of the thin film at higher frequencies, a 5-GHz microstripline resonator was fabricated. Coupled with experimental data and simulations, this study reveals a dielectric constant of ∼56 for the Nd0.5Dy0.5FeO3 thin film at 5 GHz and 300 K.

Mimicking Axons by Conductive Metal Lines Formed by Photocatalytically Grown Gold

Nanoionic memristive devices based on the field−driven migration of metal cations and oxygen vacancies have gathered high interest in the scientific community for their capability to technically mimic synaptic connections. Less attention has been given to long−range global plasticity in artificial neuronal networks. The aim of our research is to use light−stimulated growth of gold metal lines to technically mimic the growth of long−range axonal connections for neuromorphic computing architectures. For this purpose, we investigate the formation of metal lines by UV−light−stimulus−driven photocatalytic deposition of gold on titanium dioxide layers. In this study, we present a significant contribution that stems from our active involvement in CRC 1461- Neurotronics, a pivotal initiative funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation). Our research falls under Project-ID 434434223 – SFB 1461, within the broader context of Bio-inspired information pathways.0.8-mm wide photoactive titanium dioxide lines are defined by photolithography on a Sodalime glass substrate. We deposited a 70 nm thick titanium dioxide line on a 10 nm thick indium tin oxide adhesion layer by DC sputtering. The substrate was then heat treated for 90 minutes at 400°C and subsequently cooled on a metal plate to achieve the photocatalytically active anatase phase of titanium dioxide [1]. The growth process is conducted in a beaker by reduction from an aqueous gold chloride precursor solution (HAuCl4). In each step of the growth process, the substrate is placed in a beaker containing 15 ml of the precursor. The solution is obtained by dissolving 15 mg of HAuCl4 powder in 60 ml of deionized water. We utilize a UV LED with the peak wavelength of 365 nm and an approximate intensity of 1.8 - 2.7 mW/cm² to illuminate the sample in the beaker. The illumination time and UV intensity are crucial for this dynamic process. Here, we illuminated the sample for 12 hours and refreshed the solution every 2 hours. After each refreshment of the solution, the substrate is washed thoroughly with deionized (DI) water and is dried under nitrogen gas. We analyze the surface properties of grown gold utilizing scanning electron microscopy (SEM) and measure the conductance of the grown lines by applying voltage via the needles of a hard contact probe station.In the first experiments the growth of gold clusters on the surface is observed instead of the homogeneous gold coverage of the photolithographically defined titanium dioxide lines, which are needed for long-range electrical connections. Then, we coincidentally observed that the presence of a scratch on the titanium dioxide line led to the growth of continuous gold lines on the damaged area. Subsequently, deliberate scratches were introduced manually using tweezers, varying in both size and thickness. SEM images depict islands and covered areas, with notable growth observed on the scratched regions. Remarkably, wider scratches exhibit a proportionally increased width of the grown lines, and a uniform line devoid of any gaps is distinctly visible on broader scratches. We observed particle growth on thinner lines. However, unlike the uniform alignment observed in wider scratches, these particles did not coalesce into a continuous line. Instead, they remained separated from each other, exhibiting small gaps between individual particles. The morphological analysis of the grown gold line using SEM reveals a crystalline morphology of particles.As the primary objective of this research is to mimic axons with gold lines, ensuring conductivity is crucial for obtaining long−range electrical connections mimicking axons. To achieve this, voltage was applied using the needles of a hard contact probe station, and the resulting current was measured. The linear behavior observed in the I–V diagram of the wider line serves as a confirmation of its conductance (≈0.003 S).

Thin lines between native and invasive aquatic plants are common, posing challenges for response efforts

Abstract Lines separating native and invasive plant species can be thin due to close relatedness, obscured by cryptic invasions, or breached by hybridization. Past work suggests these phenomena are especially prevalent in aquatic systems. This could arise from strong filters imposed by aquatic environments magnifying the importance of ‘preadaptation’—non‐native species succeeding where closely related native species occur due to shared traits. If so, there should be stronger signals of preadaptation in aquatic than terrestrial plant invasions, with implications for management. I tested for stronger influence of preadaptation in aquatic than terrestrial invasions by comparing relatedness of invasive and native species in aquatic versus terrestrial flora of the Midwestern USA using herbarium records and taxonomic and phylogenetic analyses. I predicted that aquatic species would constitute an evolutionarily distinct subset of plants; aquatic invaders would be more closely related, taxonomically and phylogenetically, to native aquatic plants than terrestrial invaders are to their native counterparts; and aquatic invaders from the Midwest's primary donor region (the Palearctic) would be more closely related to Midwestern species than are Palearctic aquatic plants that are not invasive in the Midwest. Findings supported the evolutionary legacy of adaptation to aquatic environments being reflected in thin lines separating invasive and native aquatic plants. Aquatic species constituted an evolutionarily distinct subset of plants, and invasive aquatic plants were more closely related to native aquatic plants (taxonomically and phylogenetically) than terrestrial invaders were to terrestrial native species. Additionally, aquatic plants of the Palearctic that are invasive in the Midwest were more closely related to Midwestern natives (phylogenetically, but not taxonomically) than were their non‐invasive counterparts, reinforcing the role of preadaptation. Synthesis and applications: Thin lines separating native from invasive aquatic plants pose challenges for response efforts. For resource managers, the prevalence of cryptic invasions requires dedicated, robust approaches to surveillance. For outreach, finer distinctions between native and invasive necessitate nuanced approaches to communication and education. And when control is needed, it should be implemented cautiously to minimize nontarget impacts to close native relatives, but thoroughly enough to prevent native relatives being displaced by competition and/or introgression.