Kramers-Kronig relation in gravitational lensing

The Kramers-Kronig relation is a well-known relation, especially in the field of optics. The key to this relation is the causality that output comes only after input. We first show that gravitational lensing obeys the causality in the sense that (electromagnetic/gravitational) waves emitted from the source arrive at an observer only after the arrival of the signal in geometrical optics. This is done by extending the previous work which is based on the thin lens approximation. We then derive the Kramers-Kronig relation in gravitational lensing, as the relation between real and imaginary parts of the amplification factor, which is the amplitude ratio of the lensed wave to the unlensed wave. As a byproduct, we find a new relation that equates integration of the square of the real part of the amplification factor over frequency to that for the imaginary part of the amplification factor. We also obtain a sum rule which relates the integral of the imaginary part of the amplification factor with the magnification of the first arrival image in geometrical optics. Finally, we argue that an incorrect separation of the observed gravitational waveform into the amplification factor and the unlensed waveform generically leads to the violation of the Kramers-Kronig relation. Our work suggests that examining the violation of the Kramers-Kronig relation may be used for correctly extracting the lensing signal in the gravitational wave observations.Comment: 17 pages, 5 figure

Skeletal Mandibular Protrusion with Impacted Ankylosed Teeth

Aim: To present a case of skeletal mandibular protrusion with multiple impacted ankylosed teeth, which were treated with conventional orthognathic surgery and alveolar corticotomy, respectively. Background: Tooth ankylosis is characterized by the fusion of a root surface with the surrounding alveolar bone. Various treatment modalities for tooth ankylosis have been developed and are used commonly in the clinic. Corticotomy is defined as the application of intentional surgical injury to the cortical bone to mobilize a tooth with the adjacent bone and soft tissues. The corticotomy technique has been improved in recent years to avoid possible risks such as periodontal damage, tooth devitalization, and osseous necrosis due to an inadequate blood supply. Case description: A female patient aged 16 years and 3 months was diagnosed with anterior crossbite and the impaction and ankylosis of multiple canines. After the confirmation of ankylosis, alveolar corticotomy was performed on the maxillary left and mandibular right canines. After 6 months of traction (patient age, 19 years and 7 months), both canines had extruded successfully. After the completion of preoperative treatment, bilateral intraoral vertical ramus osteotomy was performed to correct the anterior crossbite involving a skeletal mandibular protrusion. The amounts of mandibular setback on the right and left sides were approximately 7 and 5 mm, respectively. The total treatment period was 55 months. Acceptable occlusion with a balanced profile was maintained over a 5-year retention period, indicating the long-term stability and success of the treatment. Conclusion: Our results indicate that alveolar corticotomy should be considered to facilitate the treatment of multiple impacted ankylosed teeth. Clinical significance: This report proposes an efficacy of alveolar corticotomy for extrusion of impacted ankylosed teeth

Diversity of preferred nucleotide sequences around the translation initiation codon in eukaryote genomes

Understanding regulatory mechanisms of protein synthesis in eukaryotes is essential for the accurate annotation of genome sequences. Kozak reported that the nucleotide sequence GCCGCC(A/G)CCAUGG (AUG is the initiation codon) was frequently observed in vertebrate genes and that this ‘consensus’ sequence enhanced translation initiation. However, later studies using invertebrate, fungal and plant genes reported different ‘consensus’ sequences. In this study, we conducted extensive comparative analyses of nucleotide sequences around the initiation codon by using genomic data from 47 eukaryote species including animals, fungi, plants and protists. The analyses revealed that preferred nucleotide sequences are quite diverse among different species, but differences between patterns of nucleotide bias roughly reflect the evolutionary relationships of the species. We also found strong biases of A/G at position −3, A/C at position −2 and C at position +5 that were commonly observed in all species examined. Genes with higher expression levels showed stronger signals, suggesting that these nucleotides are responsible for the regulation of translation initiation. The diversity of preferred nucleotide sequences around the initiation codon might be explained by differences in relative contributions from two distinct patterns, GCCGCCAUG and AAAAAAAUG, which implies the presence of multiple molecular mechanisms for controlling translation initiation

Feasibility study of a novel wireless localization technique using radiofrequency identification markers for small and deeply located lung lesions

Objectives: To evaluate the safety and efficacy of a novel wireless localization technique that uses radiofrequency identification markers for small and deep lung lesions. Methods: Preliminary use of the device was retrospectively evaluated in 2 Japanese centers. Under general anesthesia, a marker was placed as close as possible to the tumor via computed tomography-guided bronchoscopy in a hybrid operation theater. Surgeons located the marker without lung palpation using a detection probe the tone of which changed to indicate the marker-probe distance. Efficacy was defined as functional marker placement (bronchoscopy time and marker position) and deep margin distance. Results: Twelve markers were placed for 11 lesions (mean size, 6.8 ± 2.7 mm) located at a mean depth from the pleura of 11.4 ± 8.4 mm (range = 0-26.0 mm). Of 12 markers, 7 markers (58.3%) were placed within 10 mm from the lesion in 25.5 ± 14.4 minutes. For the 11 wedge resections, markers were placed at a mean distance of 6.7 mm (range, 0-13.0 mm) from the lesion and a mean distance of 14.4 mm (range, 3.0-42.0 mm) from the pleura. All markers were recovered without complications, and all tumors were resected with negative margins. For 5 lesions >10 mm deep to the pleura (mean depth, 18.9 ± 5.5 mm; range, 11.0-26.0 mm), the median depth of the surgical margin was 11.6 ± 2.1 mm (range, 9.0-14.0 mm). Conclusions: Radiofrequency identification marking was safe and precisely localized small lung lesions, including their depth

Identifying participants with knee osteoarthritis likely to benefit from physical therapy education and exercise: A hypothesis-generating study

Background: The purpose of this investigation was to undertake a hypothesis generating study to identify candidate variables that characterize people with knee osteoarthritis who are most likely to experience a positive response to exercise. Methods: One hundred and fifty participants with knee osteoarthritis participated in this observational, longitudinal study. All participants received a standard exercise intervention that consisted of 20-min sessions two to three times a week for three months. The classification and regression tree methodology (CART) was used to develop prediction of positive clinical outcome. Positive pain and disability outcomes (dependent variables) were defined as an improvement in pain intensity by \u3e50% or an improvement of five or more on the Oxford knee score, respectively. The predictor variables considered included age, sex, body mass index, knee osteoarthritis severity (Kellgren/Lawrence grade), pain duration, use of medication, range of knee motion, pain catastrophizing, self-efficacy and knee self-perception. Results: Fifty-five participants (36.6%) were classified as responders for pain intensity and 36.6% were classified as responders for disability. The CART model identified impairments in knee self-perception and knee osteoarthritis severity as the discriminators for pain intensity reduction following exercise. No variables predicted reduction of disability level following exercise. Conclusions: Such findings suggest that both body perception and osteoarthritis severity may play a role in treatment outcome with exercise. It also raises the possibility that those with higher levels of disrupted body perception may need additional treatment targeted at restoring body perception prior to undertaking exercise. Significance: Regardless age, sex, body mass index, pain duration, use of medication, knee range of motion, pain catastrophizing and self-efficacy, participants with knee osteoarthritis who report low levels of body perception disruption (a FreKAQ score ≦ 17) and minimal structural changes (KL grade I) demonstrate significantly better outcomes from exercise therapy than other participants

Observation of domain wall bimerons in chiral magnets

Topological defects embedded in or combined with domain walls have been proposed in various systems, some of which are referred to as domain wall skyrmions or domain wall bimerons. However, the experimental observation of such topological defects remains an ongoing challenge. Here, using Lorentz transmission electron microscopy, we report the experimental discovery of domain wall bimerons in chiral magnet Co-Zn-Mn(110) thin films. By applying a magnetic field, multidomain structures develop, and simultaneously, chained and isolated bimerons arise as the localized state between the domains with the opposite in-plane components of net magnetization. The multidomain formation is attributed to magnetic anisotropy and dipolar interaction, and domain wall bimerons are stabilized by the Dzyaloshinskii-Moriya interaction. In addition, micromagnetic simulations show that domain wall bimerons appear for a wide range of conditions in chiral magnets with cubic magnetic anisotropy. Our results promote further study in various fields of physics.Comment: 30 pages, 10 figures (including Supplementary Materials

Endogenous agonist–bound S1PR3 structure reveals determinants of G protein–subtype bias

脂質受容体の新たな活性化機構を解明 --脂質がまっすぐ伸びて活性化--. 京都大学プレスリリース. 2021-06-10.Sphingosine-1-phosphate (S1P) regulates numerous important physiological functions, including immune response and vascular integrity, via its cognate receptors (S1PR1 to S1PR5); however, it remains unclear how S1P activates S1PRs upon binding. Here, we determined the crystal structure of the active human S1PR3 in complex with its natural agonist S1P at 3.2-Å resolution. S1P exhibits an unbent conformation in the long tunnel, which penetrates through the receptor obliquely. Compared with the inactive S1PR1 structure, four residues surrounding the alkyl tail of S1P (the “quartet core”) exhibit orchestrating rotamer changes that accommodate the moiety, thereby inducing an active conformation. In addition, we reveal that the quartet core determines G protein selectivity of S1PR3. These results offer insight into the structural basis of activation and biased signaling in G protein–coupled receptors and will help the design of biased ligands for optimized therapeutics