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Chiral structures, breaking spatial inversion symmetry, exhibit non-zero chiroptical activity (COA) due to the coupling between their electric and magnetic responses under external electromagnetic fields, an effect absent in achiral systems. Non-magnetic chiral structures also exhibit Chiral-Induced Spin Selectivity (CISS), primarily detected in two terminal measurements in the linear regime, where spin selection emerges without external magnetic influence. Despite the different origins of these physical phenomena, our model captures the relevant physics required to address CISS as an intrinsic molecular effect with the basic ingredients: (i) chirality/inversion asymmetry, (ii) meV atomic spin–orbit coupling, and (iii) decoherence as a source of reciprocity breaking. In this work, we derived how the electronic system couples with polarized electromagnetic radiation to yield a spin-dependent polarization rotation power, quantified through the Rosenfeld tensor, predicting characteristic spin signatures in the COA. The model also predicts that a net spin polarization manifests in the molecular terminations that have been surmised as an explanation for chiral species separation of racemic mixtures and interactions with surface magnetic domains. A recent sensitive spectroscopic measurement of electron transfer in donor–acceptor complexes is consistent with the standalone CISS effect. [ABSTRACT FROM AUTHOR]

There is increasing interest in the study of chiral degrees of freedom occurring in matter and in electromagnetic fields. Opportunities in quantum sciences will likely exploit two main areas that are the focus of this Review: (1) recent observations of the chiral-induced spin selectivity (CISS) effect in chiral molecules and engineered nanomaterials and (2) rapidly evolving nanophotonic strategies designed to amplify chiral light-matter interactions. On the one hand, the CISS effect underpins the observation that charge transport through nanoscopic chiral structures favors a particular electronic spin orientation, resulting in large room-temperature spin polarizations. Observations of the CISS effect suggest opportunities for spin control and for the design and fabrication of room-temperature quantum devices from the bottom up, with atomic-scale precision and molecular modularity. On the other hand, chiral-optical effects that depend on both spin- and orbital-angular momentum of photons could offer key advantages in all-optical and quantum information technologies. In particular, amplification of these chiral light-matter interactions using rationally designed plasmonic and dielectric nanomaterials provide approaches to manipulate light intensity, polarization, and phase in confined nanoscale geometries. Any technology that relies on optimal charge transport, or optical control and readout, including quantum devices for logic, sensing, and storage, may benefit from chiral quantum properties. These properties can be theoretically and experimentally investigated from a quantum information perspective, which has not yet been fully developed. There are uncharted implications for the quantum sciences once chiral couplings can be engineered to control the storage, transduction, and manipulation of quantum information. This forward-looking Review provides a survey of the experimental and theoretical fundamentals of chiral-influenced quantum effects and presents a vision for their possible future roles in enabling room-temperature quantum technologies.

Ultramafic ecosystems are renowned for high endemism and habitat specialization. However, most of our understanding of ultramafic plant ecology comes from Mediterranean and temperate climes, raising questions about the generalizability of plant responses to ultramafic soils. This is especially apparent in tropical ultramafic ecosystems which exhibit a wide range of endemism and differentiation between ultramafic and adjacent non-ultramafic soils. Our objectives were two-fold: 1) synthesize our understanding of tropical ultramafic plant ecology, paying particular attention to generalities that may explain variation in endemism and habitat specialization among tropical ultramafic ecosystems; and 2) define an interdisciplinary research agenda using tropical ultramafic ecosystems as a macroecological model. We demonstrate that tropical ultramafic floras are diverse and variable in plant form and function due to the interactive effects of biogeography, climate, and edaphic properties. The variable rates of endemism, specialization, and stress tolerance traits across tropical ultramafic ecosystems have implications for the management and conservation of these diverse systems. Los ecosistemas ultramaficos son reconocidos por su endemismo y especializacion del habitat. Sin embargo, la mayor parte de nuestra comprension de la ecologia vegetal ultramafica proviene de climas mediterraneos y templados, lo que plantea dudas sobre la generalizacion de las respuestas de las plantas a los suelos ultramaficos. Esto es especialmente evidente en los ecosistemas tropicales ultramaficos que exhiben una amplia gama de endemismo y diferenciacion entre suelos tropicales ultramaficos y no ultramaficos adyacentes. Nosotros teniamos dos objetivos: 1) sintetizar nuestra comprension actual de la ecologia de las plantas tropicales ultramaficas, prestando especial atencion a las generalidades que pueden explicar la variacion en el endemismo y la especializacion del habitat entre los ecosistemas tropicales ultramaficos; y 2) definir una agenda de investigacion interdisciplinaria utilizando ecosistemas ultramaficos tropicales como modelo macroecologico. Las floras tropicales ultramaficas son diversas y variables en la forma y funcion de las plantas debido a los efectos interactivos de la biogeografia, el clima y las propiedades edaficas. Las tasas variables de endemismo, especializacion y rasgos de tolerancia al estres en los ecosistemas tropicales ultramaficos tienen implicaciones para el manejo y conservacion de estos diversos sistemas. Keywords Edaphic * Endemism * Hyperaccumulator * Metallophyte * Serpentine * Unusual soil, Introduction Ultramafic (serpentine) soils have long attracted scientific attention due to their specialized flora and ecological and evolutionary implications. However, our understanding of ultramafic plant ecology remains dominated by research [...]

Objective: This study describes the frequency of obstetric anal sphincter injuries (OASIS) in patients after instrumental delivery according to the type of forceps used. Methods: A retrospective comparative cohort study was conducted on patients who underwent instrumental delivery from January 2017 to April 2022. The primary outcome was the presence of OASIS following delivery. Patients were categorized into Cohort A if only rotation forceps were used, Cohort B for only traction forceps, and Cohort C if both types were used sequentially. Statistical analysis was performed with SPSS (IBM, New York, NY) with χ2, Fisher's exact, and analysis of variance testing. A P‐value <0.05 was considered significant. Results: OASIS occurred in 45 of 328 instrumental deliveries. OASIS after rotation forceps occurred in 12.9% (n = 8) of cases, after traction forceps in 13.2% (n = 34), and after sequential use of rotation and traction forceps in 37.5% (n = 3) of cases (p = 0.141). An odds ratio (OR) of 0.91 (95% confidence interval [CI] 0.40–2.08) for OASIS was obtained with the use of rotation forceps, 0.81 (95% CI 0.38–1.70) for traction forceps, and 3.97 (95% CI 0.91–17.2) for the sequential use of rotation and traction forceps. Conclusion: There were no significant differences in the presence of OASIS comparing traction and rotation forceps. A non‐significant trend of higher OASIS following the sequential use of traction and rotation forceps was observed. SYNOPSIS: This study investigates obstetric anal sphincter injuries after instrumental delivery, finding no significant difference between rotation and traction forceps in the Mexican population. [ABSTRACT FROM AUTHOR]

We address the electron-spin-phonon coupling in an effective model Hamiltonian for DNA to assess its role in spin transfer involved in the Chiral-Induced Spin Selectivity (CISS) effect. The envelope function approach is used to describe semiclassical electron transfer in a tight-binding model of DNA at half filling in the presence of intrinsic spin–orbit coupling. Spin-phonon coupling arises from the orbital-configuration dependence of the spin–orbit interaction. We find spin-phonon coupling only for the acoustic modes, while the optical modes exhibit electron–phonon interaction without coupling to spin. We derive an effective Hamiltonian whose eigenstates carry spin currents that are protected by spin-inactive stretching optical modes. As optical phonons interact more strongly than acoustic phonons, side buckling and tilting optical base modes will be more strongly associated with decoherence, which allows for the two terminal spin filtering effects found in CISS. [ABSTRACT FROM AUTHOR]

Introduction: Despite the increasing popularity of social media, little research has been conducted on its impact on lifestyle behaviors and health outcomes among adults. This study aimed to investigate whether more frequent social media screen time use is associated with poorer lifestyle behaviors, overweight or obesity, and depressive symptoms. Additionally, this study examined the potential use of social media to positively influence health. Methods: An anonymous one‐time survey was conducted among English‐speaking social media users aged 18–34 in Southern California. Self‐reported height and weight were used to calculate body mass index (BMI), and the Patient Health Questionnaire‐9 (PHQ‐9) was used to estimate the severity of depressive symptoms. A cumulative risk score for lifestyle behaviors was also tallied. Three focus groups were held with a subset of the survey population to gain insights on social media, lifestyle behaviors, and health. A mixed method analysis was used to analyze the data. Results: The survey data of 86 complete cases showed a positive correlation (r = 0.421; p < 0.001; 95% confidence interval [CI] [0.223, 0.585]) among PHQ‐9 depression scores and negative correlation (r = −0.230; p = 0.033; 95% CI [−0.426, −0.12]) for BMI compared to actual social media screen time usage, respectively. However, social media screen time usage ≥3 h showed no association for either BMI, depressive symptoms, or cumulative risk score. Participants viewed social media as a "double‐edged sword," providing benefits such as "connection" and "information sharing," but also having a negative impact on mental health (theme 1). Participants also believed public health needs to take a more proactive role in using social media, while social media platforms should manage the "authenticity" of content and modify their "algorithms" to improve health and lifestyle practices (theme 2). Conclusions: This study suggested that social media may have some protective benefits related to becoming overweight or obese as indicated by the focus group participants, but further research is needed on the relationship between social media screen time usage and adult mental health. Social media platforms may have the potential to promote positive lifestyle behaviors and improve health if used properly. [ABSTRACT FROM AUTHOR]