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To throw away unopened
\"At the launch party for her memoir in 2014, Viv Albertine received the news her mother was dying. She left the party immediately and spent a few final hours with a woman who had been an enormous presence and force in her life. In the weeks that followed, Viv was left with the task of sorting through her mother's affairs. In that process she came across one fatally curious item: a bag labelled 'To throw away unopened'. This auspicious moment lies at the heart of Viv Albertine's second book, part memoir, part manifesto, part polemic in which she touches on sex, ageing, feminism (in all its guises) and other conundrums that characterise the 21st century life. It is a bold and unapologetic follow-up to a book which became a sensation by a musician and writer who sits at the heart of the counter-cultural landscape today as a celebrated and feted figure.\"-- Provided by publisher.
Book
Effect of the difference in slit locations on the suppression of cavitation instabilities in an inducer
Cavitation instabilities are caused by unsteady cavitation in the inducer in liquid rocket turbopumps. This phenomenon has a negative impact on pumps and must be suppressed. Our research group has proposed a method to suppress the instabilities by adding slits to the inducer blades, and previous studies was shown the effectiveness of this method. In this study, water experiments of inducers with slits at different locations were conducted. As a results, the vibration characteristics of cavitation in the slit inducers changed when the location of the slit was changed although the cavitation instabilities were successfully suppressed in all slit inducer. The visualized image of cylindrical surface of the axial flow pump was expanded into a two-dimensional plane to determine the time variation of the area of the tip leakage vortex cavitation generated in each blade. The suppression mechanism of cavitation instabilities in each slit location was discussed from the obtained unsteady image of cavity area in each blade in the slit inducers.
Journal Article
HIV and antiretroviral therapy-related fat alterations
Early in the HIV epidemic, lipodystrophy, characterized by subcutaneous fat loss (lipoatrophy), with or without central fat accumulation (lipohypertrophy), was recognized as a frequent condition among people living with HIV (PLWH) receiving combination antiretroviral therapy. The subsequent identification of thymidine analogue nucleoside reverse transcriptase inhibitors as the cause of lipoatrophy led to the development of newer antiretroviral agents; however, studies have demonstrated continued abnormalities in fat and/or lipid storage in PLWH treated with newer drugs (including integrase inhibitor-based regimens), with fat gain due to restoration to health in antiretroviral therapy-naive PLWH, which is compounded by the rising rates of obesity. The mechanisms of fat alterations in PLWH are complex, multifactorial and not fully understood, although they are known to result in part from the direct effects of HIV proteins and antiretroviral agents on adipocyte health, genetic factors, increased microbial translocation, changes in the adaptive immune milieu after infection, increased tissue inflammation and accelerated fibrosis. Management includes classical lifestyle alterations with a role for pharmacological therapies and surgery in some patients. Continued fat alterations in PLWH will have an important effect on lifespan, healthspan and quality of life as patients age worldwide, highlighting the need to investigate the critical uncertainties regarding pathophysiology, risk factors and management.
HIV and antiretroviral therapy-related fat alterations are frequent in people living with HIV and include fat loss, fat gain and obesity. This Primer discusses the changing epidemiology, mechanisms, diagnosis and treatment of these alterations.
Journal Article
Trapping and detecting nanoplastics by MXene-derived oxide microrobots
Nanoplastic pollution, the final product of plastic waste fragmentation in the environment, represents an increasing concern for the scientific community due to the easier diffusion and higher hazard associated with their small sizes. Therefore, there is a pressing demand for effective strategies to quantify and remove nanoplastics in wastewater. This work presents the “on-the-fly” capture of nanoplastics in the three-dimensional (3D) space by multifunctional MXene-derived oxide microrobots and their further detection. A thermal annealing process is used to convert Ti
3
C
2
T
x
MXene into photocatalytic multi-layered TiO
2
, followed by the deposition of a Pt layer and the decoration with magnetic γ-Fe
2
O
3
nanoparticles. The MXene-derived γ-Fe
2
O
3
/Pt/TiO
2
microrobots show negative photogravitaxis, resulting in a powerful fuel-free motion with six degrees of freedom under light irradiation. Owing to the unique combination of self-propulsion and programmable Zeta potential, the microrobots can quickly attract and trap nanoplastics on their surface, including the slits between multi-layer stacks, allowing their magnetic collection. Utilized as self-motile preconcentration platforms, they enable nanoplastics’ electrochemical detection using low-cost and portable electrodes. This proof-of-concept study paves the way toward the “on-site” screening of nanoplastics in water and its successive remediation.
Nanoplastic water pollution represents an increasing concern. Here, photogravitactic MXene-derived microrobots are programmed to trap nanoplastics in the layered structure and magnetically transfer them to low-cost electrodes for further detection.
Journal Article
Size effect in ion transport through angstrom-scale slits
In the field of nanofluidics, it has been an ultimate but seemingly distant goal to controllably fabricate capillaries with dimensions approaching the size of small ions and water molecules. We report ion transport through ultimately narrow slits that are fabricated by effectively removing a single atomic plane from a bulk crystal. The atomically flat angstrom-scale slits exhibit little surface charge, allowing elucidation of the role of steric effects. We find that ions with hydrated diameters larger than the slit size can still permeate through, albeit with reduced mobility. The confinement also leads to a notable asymmetry between anions and cations of the same diameter. Our results provide a platform for studying the effects of angstrom-scale confinement, which is important for the development of nanofluidics, molecular separation, and other nanoscale technologies.
Journal Article
Double-slit time diffraction at optical frequencies
Double-slit experiments—where a wave is transmitted through a thin double aperture in space—have confirmed the wave–particle duality of quantum objects, such as single photons, electrons, neutrons, atoms and large molecules. Yet, the temporal counterpart of Young’s double-slit experiment—a wave interacting with a double temporal modulation of an interface—remains elusive. Here we report such a time-domain version of the classic Young’s double-slit experiment: a beam of light twice gated in time produces an interference in the frequency spectrum. The ‘time slits’, narrow enough to produce diffraction at optical frequencies, are generated from the optical excitation of a thin film of indium tin oxide near its epsilon-near-zero point. The separation between time slits determines the period of oscillations in the frequency spectrum, whereas the decay of fringe visibility in frequency reveals the shape of the time slits. Surprisingly, many more oscillations are visible than expected from existing theory, implying a rise time that approaches an optical cycle. This result enables the further exploration of time-varying physics, towards the spectral synthesis of waves and applications such as signal processing and neuromorphic computation.A temporal version of Young’s double-slit experiment shows characteristic interference in the frequency domain when light interacts with time slits produced by ultrafast changes in the refractive index of an epsilon-near-zero material.
Journal Article
Design of Ultrahigh Energy Resolution RIXS Beamline at NanoTerasu
The optical design of the ultrahigh-resolution RIXS beamline, which is currently developed at NanoTerasu in Japan, is described. The main goal of this beamline is to perform ultrahigh-resolution RIXS measurements with a total energy resolution of <10 meV at 250–1000 eV with E /Δ E >150,000 for both beamline and RIXS spectrometer. To achieve the ultra-high resolution, a 2D-RIXS spectrometer using energy-dispersive X-ray is employed to compensate for lower throughput at higher energy resolution, and the optics of the beamline is optimized for the 2D-RIXS spectrometer. A vertically dispersing in-focus variable-included-angle varied-line-spacing plane grating monochromator is employed for the beamline, with an entrance slit to ensure the ultrahigh resolution. First and second mirrors focus X-ray on entrance slits vertically and horizontally, respectively, and the divergent X-ray is irradiated onto the grating. For the 2D-RIXS spectrometer, there is no exit slit, and the vertically energy-dispersed X-ray is irradiated directly onto a sample. In front of the sample, X-ray is horizontally refocused by a Wolter type-I mirror. The expected horizontal focus size at the sample is ~0.7 μm. The expected photon flux is ~1×10 11 photons/s at 500–1000 eV with a virtual slit width of 2 μm required for E /Δ E >150,000. The height of the dispersed X-ray available in the 2D-RIXS spectrometer is ~120 μm, which allows the use of a remarkably high flux of ~6×10 12 photons/s, and the beamline will serve as an ultrahigh-resolution and high-efficiency RIXS facility.
Journal Article
Positional shunt assist for slit ventricle syndrome
Purpose
Hydrocephalus is one of the most common pathologies in pediatric neurosurgery. One of the causes of recurring events of headaches among shunted children is “slit ventricle syndrome” (SVS). Several potential treatments have been proposed, yet SVS often represents a treatment challenge. The goal of the current series is to present our experience with adding a positional shunt-assist (SA) (Miethke, Aesculap) for the treatment of SVS.
Methods
Clinical data was retrospectively collected from all consecutive children with SVS that were treated with SA (Miethke, Aesculap) at our center. Surgical and clinical outcomes as expressed by hospital visits, or need for additional surgery, were evaluated.
Results
Nine cases were included. Hydrocephalus etiology included IVH (6), postinfectious (1), and congenital syndromes (2). Average age at first shunt was 4 months. Primary shunt type was differential-pressure-valve in all. Average age at SVS onset was 4 years. Average age at SA placement was 5.5 years. There were no perioperative complications besides a single stich abscess. A 6-month follow-up period after SA was compared to a 6-month period prior to the SA: average hospital visits decreased from 2.4 to 0.6 per patient (
p
< 0.0002). 4/9 patients needed an LP or shunt revision before the SA surgery, while no procedure was indicated during the immediate 6-month follow-up. At the last follow-up, there was a significant reduction in the rate of ER visits compared to prior to surgery; however, the number of neurosurgical procedures did not significantly differ.
Conclusion
Using a SA for SVS was associated with a short-term improvement of symptoms in the majority of cases, reduction in hospital visits, and reduced need for SVS-related procedures.
Journal Article
Finally making sense of the double-slit experiment
Feynman stated that the double-slit experiment “... has in it the heart of quantum mechanics. In reality, it contains the only mystery” and that “nobody can give you a deeper explanation of this phenomenon than I have given; that is, a description of it” [Feynman R, Leighton R, Sands M (1965) The Feynman Lectures on Physics]. We rise to the challenge with an alternative to the wave function-centered interpretations: instead of a quantum wave passing through both slits, we have a localized particle with nonlocal interactions with the other slit. Key to this explanation is dynamical nonlocality, which naturally appears in the Heisenberg picture as nonlocal equations of motion. This insight led us to develop an approach to quantum mechanics which relies on preand postselection, weak measurements, deterministic, and modular variables. We consider those properties of a single particle that are deterministic to be primal. The Heisenberg picture allows us to specify the most complete enumeration of such deterministic properties in contrast to the Schrödinger wave function, which remains an ensemble property. We exercise this approach by analyzing a version of the double-slit experiment augmented with postselection, showing that only it and not the wave function approach can be accommodated within a time-symmetric interpretation, where interference appears even when the particle is localized. Although the Heisenberg and Schrödinger pictures are equivalent formulations, nevertheless, the framework presented here has led to insights, intuitions, and experiments that were missed from the old perspective.
Journal Article
Asymmetric CPW-fed patch antenna with slits at terahertz applications for 6G wireless communications
This paper presents a compact portable patch antenna for 6G wireless communications at terahertz (THz) applications. The asymmetric co-planer waveguide (CPW) fed curved slits are proposed on rectangular microstrip patch antenna to resonate at THz applications. The asymmetric CPW-fed antenna is designed to be 50 μm thick on FR-4 substrate with 500 × 500 µm
2
rectangular substrate with gold plating patch (thickness is 0.02 μm). The designed antenna is offers dual bands and resonates 0.813 THz, 1.254 THz frequencies. The first resonating frequency has a return loss of -16.86 dB is observed with the impedance bandwidth of 92 GHz (0.761 THz-0.853 THz) and gain is 6.14 dBi. The return loss of -28.52dB is observed over the impedance bandwidth of 295 GHz (1.117 THz-1.413 THz) with a realized gain of 7.31dBi at a second resonating frequency of 1.254 THz. The results obtained for the proposed design antenna have wider impedance bandwidth and more gain with a low reflection coefficient for high-speed wireless data communication systems. The proposed compact terahertz antenna is used in 6G applications for ultra-high-speed wireless communications with support to connect massive devices.
Journal Article