Formation of robust bound states of interacting microwave photons.

Systems of correlated particles appear in many fields of modern science and represent some of the most intractable computational problems in nature. The computational challenge in these systems arises when interactions become comparable to other energy scales, which makes the state of each particle depend on all other particles1. The lack of general solutions for the three-body problem and acceptable theory for strongly correlated electrons shows that our understanding of correlated systems fades when the particle number or the interaction strength increases. One of the hallmarks of interacting systems is the formation of multiparticle bound states2-9. Here we develop a high-fidelity parameterizable fSim gate and implement the periodic quantum circuit of the spin-½ XXZ model in a ring of 24 superconducting qubits. We study the propagation of these excitations and observe their bound nature for up to five photons. We devise a phase-sensitive method for constructing the few-body spectrum of the bound states and extract their pseudo-charge by introducing a synthetic flux. By introducing interactions between the ring and additional qubits, we observe an unexpected resilience of the bound states to integrability breaking. This finding goes against the idea that bound states in non-integrable systems are unstable when their energies overlap with the continuum spectrum. Our work provides experimental evidence for bound states of interacting photons and discovers their stability beyond the integrability limit.

Accurately computing the electronic properties of a quantum ring.

A promising approach to study condensed-matter systems is to simulate them on an engineered quantum platform1-4. However, the accuracy needed to outperform classical methods has not been achieved so far. Here, using 18 superconducting qubits, we provide an experimental blueprint for an accurate condensed-matter simulator and demonstrate how to investigate fundamental electronic properties. We benchmark the underlying method by reconstructing the single-particle band structure of a one-dimensional wire. We demonstrate nearly complete mitigation of decoherence and readout errors, and measure the energy eigenvalues of this wire with an error of approximately 0.01 rad, whereas typical energy scales are of the order of 1 rad. Insight into the fidelity of this algorithm is gained by highlighting the robust properties of a Fourier transform, including the ability to resolve eigenenergies with a statistical uncertainty of 10-4 rad. We also synthesize magnetic flux and disordered local potentials, which are two key tenets of a condensed-matter system. When sweeping the magnetic flux we observe avoided level crossings in the spectrum, providing a detailed fingerprint of the spatial distribution of local disorder. By combining these methods we reconstruct electronic properties of the eigenstates, observing persistent currents and a strong suppression of conductance with added disorder. Our work describes an accurate method for quantum simulation5,6 and paves the way to study new quantum materials with superconducting qubits.

[Chronic diseases, precancer, and cancer of the lung, which are associated with pathology of the club cells of respiratory and terminal bronchioles]. / Khronicheskie zabolevaniia, predrak i rak legkikh, assotsiirovannye s patologiei bulavovidnykh kletok respiratornykh i terminal'nykh bronkhiol.

The review of the literature deals with the participation of Clara cells now called club cells (CCs) of the epithelium in the respiratory and terminal bronchioles in the pathogenesis and morphogenesis of chronic inflammatory diseases, precancer, and cancer of the lung, which develop in the respiratory segments. The review summarizes data on the histophysiology of CCs and their participation in the pathogenesis and morphogenesis of chronic interstitial lung diseases, pneumoconiosis, chronic obstructive diseases, adenomatosis, and adenocarcinoma of the lung. In this area, there is a bronchioloalveolar junction area (BAJA), one of the most important stem cell niches. CCs are located in the BAJA; they are progenitor tissue stem cells and play an important role in the regeneration of the epithelium of the respiratory bronchioles and alveoli. Pathology of CCs in the BAJA leads to the maintenance of chronic inflammation, to the destruction of the lung elastic frame, and to impaired epithelial regeneration, interstitial fibrosis, and adenomatosis. In this case, decompensated inflammation, pathological regeneration, and fibrosis develop, which, along with the action of carcinogenic agents, can contribute to the accumulation of mutations and epigenetic rearrangements in the CCs, which subsequently results in atypical adenomatous hyperplasia and adenocarcinoma of the lung.

Surgical treatment for pyogenic vertebral osteomyelitis using iodine-supported spinal instruments: initial case series of 14 patients.

Reports have detailed the increasing use of spinal instrumentation in the treatment of pyogenic vertebral osteomyelitis, with the aims of achieving a lower pseudoarthrosis rate and restoring spinal alignment. However, controversy remains over the use of instrumentation in the presence of active infection because of concerns about increased bacterial adherence and biofilm formation on the metallic implant surface. Fourteen consecutive patients were followed who were diagnosed as having pyogenic vertebral osteomyelitis and underwent surgery with spinal instrumentation with iodine-containing surfaces that could be directly supported to existing titanium implants. Bone-cage interfaces and implant-related complications after surgery were evaluated. The white blood cell (WBC) count and C-reactive protein (CRP) level were analyzed during the follow-up period. To confirm the influence of iodine release from the implant, thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were also examined. The infection subsided in all 14 patients. Both WBC counts and CRP levels returned to normal ranges by the final follow-up. One patient showed a lucent area around the screw and two patients showed lucencies inside the cage. However, no cage dislocations, cage migrations, or screw pull-outs were noted, and all patients' FT3, FT4, and TSH levels were within normal ranges during the follow-up period. We demonstrated the efficacy of iodine-supported titanium implants in the management of pyogenic vertebral osteomyelitis. No cytotoxicity or adverse effects were noted in this series.

Comparisons of accuracy of estimating percent body fat by four bioelectrical impedance devices with different frequency and induction system of electrical current.

AIM: This study aimed to compare the accuracy of estimating present body fat (%BF), using dual-energy X-ray absorptiometry (DXA) as a reference, among four BIA devices; foot-to-foot bioelectric impendence (FF-BIA), hand-to-hand BIA (HH-BIA), foot-to-hand single-frequency BIA (FH-BIASF), and foot-to-hand multiple-frequency BIA (FH-BIAMF). METHODS: Forty-four healthy college students (21 males, 172.9 ± 5.5 cm and 65.8±9.1 kg and 23 females, 160.7 ± 6.6 cm, 52.6 ± 6.17 kg) volunteered for this study. The relationship with the reference was determined by Pearson's correlation coefficient. Standard error of estimation (SEE) was calculated by regression analysis when estimating the reference measures from the predictor (BIAs). The technique of Bland-Altman was used to determine estimation bias and the limit of agreement for %BF between the reference and the predictor. RESULTS: When referenced to DXA, FF-BIA and FH-BIASF significantly overestimated %BF. The correlations with DXA were 0.90 or over, except for HH-BIA (r=0.88, P<0.05). When estimating %BFDXA by the %BF of the other methods, the lowest and highest SEE values were found in FH-BIASF (2.14%) and in HH-BIA (2.65%), respectively. The value of the limits of agreement was 10% or under in FH-BIASF and FH-BIAMF, but was 10% or over in FF-BIA and HH-BIA. CONCLUSION: Among four BIA devices, the method with the least estimation error from DXA is FH-BIASF. In comparing single-frequency BIA devices, margin of error tended to be small in FH-BIASF, and estimation bias tended to be small in FH-BIASF and HH-BIA.

Pressure-dependent magnetization and magnetoresistivity studies on tetragonal FeS (mackinawite): revealing its intrinsic metallic character.

The transport and magnetic properties of the tetragonal Fe[Formula: see text]S were investigated using magnetoresistivity and magnetization within [Formula: see text] K, [Formula: see text] 70 kOe and [Formula: see text] 3.0 GPa. In addition, room-temperature x-ray diffraction and photoelectron spectroscopy were also applied. In contrast to previously reported nonmetallic character, Fe[Formula: see text]S is intrinsically metallic but due to a presence of a weak localization such metallic character is not exhibited below room temperature. An applied pressure reduces strongly this additional resistive contribution and as such enhances the temperature range of the metallic character which, for ∼3 GPa, is evident down to 75 K. The absence of superconductivity as well as the mechanism behind the weak localization will be discussed.

[The morphology and molecular bases of damage to the stem cell niche of respiratory acini in idiopathic interstitial pneumonias].

UNLABELLED: The authors present the material of their study of the morphological and molecular biological features of damage to the stem cell niches (SCN) in the respiratory acini of the lung and the significance of their occurring changes in the pathogenesis of chronic idiopathic interstitial pneumonias (IIP), including idiopathic pulmonary fibrosis (IPF), desquamative interstitial pneumonia (DIP), cryptogenic organizing pneumonia (COP) with bronchiolitis obliterans (BO), and nonspecific interstitial pneumonia (NSIP). SUBJECTS AND METHODS: The study was performed using open transthoracic (n=181) and transbronchial (n=71) lung biopsies from 194 patients (118 cases (61%) with IPF, 35 (18%) with NSIP, 23 (12%) with DIP, 18 (9%) with COP + BO). The serial paraffin sections were stained with hematoxylin and eosin and van Gieson's picrofuchsin and immunohistochemical reactions were carried out to detect MMP-1, MMP-2, MMP-7, Apo-Cas ("Novocastra", 1:100), vimentin (Vimentin) ("LabVision" 1:100), SMA ("LabVision", 1:100), TGF-ß, TNF-α, CD34, Ost-4, and CD117 ("Dako", 1:50), CD68, and EMA ("Dako", 1:100). Biotinylated anti-mouse and anti-rabbit immunoglobulin antibodies ("Dako" LSAB + KIT, PEROXIDASE) were used as secondary antibodies. All the quantitative and semi-quantitative data obtained were processed by variation statistics. RESULTS: The compared IIPs were shown to differ in the site and degree of initial and secondary respiratory acinus damages caused by the aggressiveness of an inflammatory infiltrate and the spread of a lesion to different SCN areas involved in the regeneration of lung tissue. The mesenchymal cell with myofibroblast differentiation, which is probably associated with a mesenchymal stem cell, as evidenced by Oct-4, Vimentin, SMA, CD117, and CD34 expression by these cells, may be considered to be a marker cell of deep SCN damage. CONCLUSION: The author state that the clinical course and degree of morphological changes in IPP directly depend on the severity and depth of damage to the SCN areas of the respiratory acinus.

Stable quantum-correlated many-body states through engineered dissipation.

Engineered dissipative reservoirs have the potential to steer many-body quantum systems toward correlated steady states useful for quantum simulation of high-temperature superconductivity or quantum magnetism. Using up to 49 superconducting qubits, we prepared low-energy states of the transverse-field Ising model through coupling to dissipative auxiliary qubits. In one dimension, we observed long-range quantum correlations and a ground-state fidelity of 0.86 for 18 qubits at the critical point. In two dimensions, we found mutual information that extends beyond nearest neighbors. Lastly, by coupling the system to auxiliaries emulating reservoirs with different chemical potentials, we explored transport in the quantum Heisenberg model. Our results establish engineered dissipation as a scalable alternative to unitary evolution for preparing entangled many-body states on noisy quantum processors.

Dynamics of magnetization at infinite temperature in a Heisenberg spin chain.

Understanding universal aspects of quantum dynamics is an unresolved problem in statistical mechanics. In particular, the spin dynamics of the one-dimensional Heisenberg model were conjectured as to belong to the Kardar-Parisi-Zhang (KPZ) universality class based on the scaling of the infinite-temperature spin-spin correlation function. In a chain of 46 superconducting qubits, we studied the probability distribution of the magnetization transferred across the chain's center, [Formula: see text]. The first two moments of [Formula: see text] show superdiffusive behavior, a hallmark of KPZ universality. However, the third and fourth moments ruled out the KPZ conjecture and allow for evaluating other theories. Our results highlight the importance of studying higher moments in determining dynamic universality classes and provide insights into universal behavior in quantum systems.

[Morphological, immunohistochemical and radiological manifestation of lung tissue remodeling at lung sarcoidosis].

Sarcoidosis is a group of diseases with chronic immune inflammation and granulomas formation in the lung, lymph nodes, and others organs. Under progress of disease remodeling of the lung tissue occurs and at 20-25% of patient with sarcoidosis lung fibrosis is developed. We studied biopsies from 50 patients with sarcoidosis and 10 biopsies of pathological intact lung tissue as a control group. Roentgenologic, morphologic and immunohistochemical methods with using of mono- and polyclonal antibody to MMP 1, 2, 9 and TIMP-1, PCNA, aSMA, apo-CAS were realized. The expression levels of growth factors, apoptosis, MMPs, TIMPs were different in various clinic-morphological courses of sarcoidosis. As a rule under sarcoidosis deep remodeling of lung tissue didn't occur in spite of granulomatous inflammation. Granulomatous process, alveolitis (bronchiolitis) and sclerotic changes resulted in alteration of the lung. Cells of sarcoidosis granulomas, produced low level of MMPs and TIMP can't induce evident fibrosis and so hypertension is absent or becomes apparent in the slight form. It apparently can be link with localization of pathologic process in lung tissue without any alterations in the bronchoalveolar zone. Alveolitis under sarcoidosis conditions is notable for low activity of inflammation and doesn't result in interstitial fibrosis developing.

Noise-resilient edge modes on a chain of superconducting qubits.

Inherent symmetry of a quantum system may protect its otherwise fragile states. Leveraging such protection requires testing its robustness against uncontrolled environmental interactions. Using 47 superconducting qubits, we implement the one-dimensional kicked Ising model, which exhibits nonlocal Majorana edge modes (MEMs) with [Formula: see text] parity symmetry. We find that any multiqubit Pauli operator overlapping with the MEMs exhibits a uniform late-time decay rate comparable to single-qubit relaxation rates, irrespective of its size or composition. This characteristic allows us to accurately reconstruct the exponentially localized spatial profiles of the MEMs. Furthermore, the MEMs are found to be resilient against certain symmetry-breaking noise owing to a prethermalization mechanism. Our work elucidates the complex interplay between noise and symmetry-protected edge modes in a solid-state environment.

Realizing topologically ordered states on a quantum processor.

The discovery of topological order has revised the understanding of quantum matter and provided the theoretical foundation for many quantum error­correcting codes. Realizing topologically ordered states has proven to be challenging in both condensed matter and synthetic quantum systems. We prepared the ground state of the toric code Hamiltonian using an efficient quantum circuit on a superconducting quantum processor. We measured a topological entanglement entropy near the expected value of ­ln2 and simulated anyon interferometry to extract the braiding statistics of the emergent excitations. Furthermore, we investigated key aspects of the surface code, including logical state injection and the decay of the nonlocal order parameter. Our results demonstrate the potential for quantum processors to provide insights into topological quantum matter and quantum error correction.

Removing leakage-induced correlated errors in superconducting quantum error correction.

Quantum computing can become scalable through error correction, but logical error rates only decrease with system size when physical errors are sufficiently uncorrelated. During computation, unused high energy levels of the qubits can become excited, creating leakage states that are long-lived and mobile. Particularly for superconducting transmon qubits, this leakage opens a path to errors that are correlated in space and time. Here, we report a reset protocol that returns a qubit to the ground state from all relevant higher level states. We test its performance with the bit-flip stabilizer code, a simplified version of the surface code for quantum error correction. We investigate the accumulation and dynamics of leakage during error correction. Using this protocol, we find lower rates of logical errors and an improved scaling and stability of error suppression with increasing qubit number. This demonstration provides a key step on the path towards scalable quantum computing.

Age and sex differences of controlled force exertion measured by a computer-generated quasi-random target-pursuit system.

OBJECTIVES: This study examined age and sex differences of controlled force exertion measured by a computer-generated quasi-random target-pursuit system in 207 males and 249 females aged 15 to 86 years. METHODS: The participants matched submaximal grip exertion of their dominant hand to changing demand values, appearing as a moving quasi-random waveform on the display of a personal computer. They performed the test three times with 1-min intervals (one trial was 40 sec). The total sum of the percent of differences between the demand value and the grip exertion value for 25 sec was used as an evaluation parameter. RESULTS: The errors in controlled force exertion tended to increase constantly with age in both sexes. Significant linear regressions were identified, but there was no significant difference in the rate of increase in both sexes. Analysis of variance showed nonsignificant sex differences among means, except for those in individuals older than 60 years; significant differences between means in the groups older than the 40 yr.-old age group and the 20-24 yr.-old group were found in both sexes. CONCLUSIONS: Controlled force exertion did not show a significant sex difference and decreased gradually with age in both sexes, but decreased remarkably after 40 years of age.

[The mechanism of lung tissue remodeling in the progression of idiopathic pulmonary fibrosis].

The aim of the investigation was to study the specific features of morphological manifestations and the molecular bases of lung tissue remodeling in progressive idiopathic pulmonary fibrosis (IPF). The investigation used open and transbronchial biopsy specimens from 110 patients with IPE/idiopathic pneumonia syndrome in 1997 to 2008. Immunohistochemical analysis was carried out on serial paraffin-embedded lung tissue slices from 20 patients with IPF and 20 control patients. Immunohistochemical staining for the detection of antigens in the paraffin-embedded slices was made using the antibodies to MMP-1, MMP-2, MMP-7, TIMP-4, Apo-CAS, PCNA, PDGF, EGFR, CD34, and SMA. Nonparametric statistical methods were employed. Our findings have indicated that in early-stage IPF, there are proliferating myofibroblasts in the myofibroblastic foci, mainly in the bronchioloalveolar transitional zone (BATZ), which express PCNA and PDGF. Both in early- and late-stage IPF, there were signs of increased readiness of the alveolar and bronchiolar epithelium of BATZ for apoptosis, as judged from Apo-CAS expression. At the same time no Apo-CAS expression was recorded in the myofibroblasts. In the early stage of the disease, the expression of MMP-1, MMP-2, MMP-7, and TIMP-4 in the epitheliocytes, macrophages, fibroblasts, and myofibroblasts was higher than that in the late stage of IPF. At the same time, late-stage IPF was characterized by the higher expression in all lung tissue cells than was early-stage IPF. There was also a significant increase in vessel density in both early and late stages of IPF as compared with intact lung tissue particularly in the BATZ in the control group. Thus, lung tissue remodeling in the progression of IPF from the early to late stage of the disease comprises interrelated processes that are largely localized in the BATZ, such as immune inflammation with pathological reparation, neoangiogenesis, apoptosis, and proliferation of epitheliocytes and myofibroblasts, which lead to the development of interstitial fibrosis and adenomatosis of the lung.

[Molecular bases for the development of variants of idiopathic fibrosing alveolitis].

The purpose of the study was to examine the specific features of morphological manifestations and molecular mechanisms of controlling the processes of proliferation, apoptosis, cell differentiation, neoangiogenesis, and fibrosis, which result in lung tissue rearrangement in different types of idiopathic fibrosing alveolitis (IFA). Open and transbronchial biopsy specimens obtained from 103 patients with IFA and intact lung tissue biopsy specimens taken from those clinically diagnosed as having sarcoidosis as a control group were examined. The serial paraffin sections immunohistochemically revealed the following antigens: cytokeratins 5, 6, 7, 8, 19 (Uni-Heidelberg, DAKO), MMP 1, MMP 2, MMP 7, and TIMP 4, Apo-protein (Novocastra), Ki67, PCNA, PDGF, EGFR, CD34, SMA (smooth muscle actin), FGFb (LabVision). Biotin-conjugated antibodies to murine and rabbit immunoglobulins (Dako LSAB + KIT, PEROXIDASE) were used as secondary antibodies. The nuclei were stained with hematoxylin. Positive and negative control tests were carried out. The results of immunohistochemical tests were estimated in percentage of cells showing positive reactions (Ki67, PCNA), as well as those of a semiquantitative analysis in scores and statistical analyses (Mann-Whitney U-test, Fisher's test, and Spearman's rank correlation coefficient) were employed. OIP was ascertained to differ from other IFA in higher values of the cytokines under study, as well as in the predominant rearrangement of the lung interstice and dysregeratory epithelial changes at the site of respiratory bronchiolar transformation. At the same time there was an intensive proliferation of the epithelium and stromal cells (high expression of PCNA, PDGF by hyperplastic alveolocytes, alveolar macrophages, fibroblasts and myofibroblasts), and neogenesis (the high density of newly formed vessels with endothelial expression of CD34). Elevated alveolocytic apoptosis (from Apo-protein expression) was also observed. Cell proliferation and neoangiogenesis was attained by high MMPs expression. The practical value of the study is that the expression of the study markers may serve as a criterion for differential diagnosis and determination of prognosis in different types of IFA.

Nonlinear relationships between visceral fat area and percent regional fat mass in the trunk and the lower limbs in Japanese adults.

OBJECTIVE: The present study aimed to examine the relationship between visceral fat area (VFA) and regional fat mass (RFM) or its distribution characteristics and to compare these characteristics between normal and visceral obesity Japanese adults. SUBJECTS/METHODS: Nonobese and nonvisceral obese Japanese adults (control group (CG): 44 men and 47 women), obese but nonvisceral obese (obesity group (OG): 15 men and 21 women) and visceral obese group (VOG, 80 men and 17 women). Obesity and visceral obesity were defined as body mass index > or = 25 kg m(-2) and VFA > or = 100 cm(2), respectively, based on the criteria of the examination committee of criteria for obesity disease in Japan. RFM of the both arms, trunk and both legs were measured by DEXA, and we calculated the percent RFM (%RFM). The VFA and subcutaneous fat area were measured at the umbilicus level using CT scans. We examined the relationship between VFA and RFM or %RFM in the Japanese adult population. RESULTS: Although linear relationships were found between VFA and each RFM, nonlinear relationships were found between VFA and each %RFM. In CG, %RFM of the trunk increases and %RFM of the leg decreases with accumulating VFA, but these relationships declined in VOG. CONCLUSION: These results may suggest that the relationship between %RFM and VFA changes between different visceral obese levels, and for Japanese adults this is found at reaching a 100 cm(2) VFA, which corresponds to the criteria for visceral obesity.

Lateral dominance of stretch-shortening cycle performance in unilateral and bilateral athletes.

AIM: Few studies have been conducted on the lateral dominance of stretch-shortening cycle (SSC) performance. This study aimed to make an index for evaluation of the ability to use SSC for powerful elbow flexion and to examine the lateral dominance of SSC performance in unilateral and bilateral athletes. METHODS: Thirty-three male athletes (19.9+/-1 years) participated in this study. Each subject pulled a submaximal load (25% of maximum voluntary contraction [MVC]) in a single burst via elbow flexion of the dominant and non-dominant upper limb from the following two preliminary conditions: a static relaxed muscle state (SR condition) and using a counter-movement (SSC condition). Muscle power was measured accurately with a power instrument containing a rotary encoder, and the SSC index was calculated in order to evaluate the ability to use SSC. RESULTS: For the SSC index, the non-dominant upper limb showed higher values than the dominant upper limb. The unilateral athletes showed high values of power output when using only SSC in the dominant upper limb compared with bilateral athletes. The correlation in the SSC index between dominant and non-dominant limbs was found to be low. CONCLUSION: The non-dominant limb is superior to the dominant limb in the ability to use SSC in the upper limbs and there is the possibility of left side dominance. Unilateral athletes were superior to bilateral athletes in their ability to use SSC with their dominant limb, but a transfer of learning to the non-dominant limbs was not apparent.

Prediction of visceral fat area in Japanese adults: proposal of prediction method applicable in a field setting.

OBJECTIVE: This study aimed to develop a prediction equation for the visceral fat area at the umbilical level (VFA(L4-5)) in Japanese adults, using internal fat mass (IFM) estimated from a few anthropometric variables. METHODS: Subjects were 112 adults aged from 25 to 82 years (body mass index (BMI)=24.2+/-3.1 kg/m(2), ranged from 15.7 to 31.2 kg/m(2)). Another 60 adults aged from 21 to 71 years were recruited for the crossvalidation group (BMI=24.5+/-4.0 kg/m(2), ranged from 17.1 to 34.6 kg/m(2)). We examined (1) the prediction of IFM based on a small number of skinfold thicknesses; (2) the prediction of VFA(L4-5) using IFM and (3) the application of bioelectrical impedance analysis (BIA) measurement. VFA(L4-5) was measured by computed tomography (reference value). Total fat mass was measured by dual-energy X-ray absorptiometry (DXA) and single-frequency BIA with 8-point tactile electrodes. RESULTS: Three skinfolds at the abdomen, side chest and suprailiac were selected to estimate IFM. From IFM estimated using these three skinfolds, waist-to-hip ratio (WHR), sex and age, about 75% of the variance of VFA(L4-5) could be explained (Eq(VFA)1: R=863, R(2)=0.745, standard error of estimate (s.e.e.)=20.483 cm(2)). When substituting IFM based on BIA measurement (IFM(BIA)) into Eq(VFA)1, there were no significant mean differences from the reference in both equations, and high correlations were found (r=0.860, s.e.e.=20.902 cm(2)), although a significant mean difference in total fat mass was found between DXA and BIA measurements. The prediction equation using IFM(BIA) (Eq(VFA)2) could have prediction accuracy comparable with that of Eq(VFA)1 (Eq(VFA)2: R=879, R(2)=0.773, s.e.e.=20.324 cm(2)). Furthermore, when applying these equations to the crossvalidation group, there were cross-validity in both equations. CONCLUSION: This study proposed a prediction equation for VFA(L4-5) from WHR and IFM based on three skinfolds, and the validity of BIA measurement in Japanese adults. We can propose the procedure for a field setting.

Influence of changes in visual acuity under various visual field conditions on the spectral characteristics of center of pressure sway.

AIM: This study aimed to examine the influence of visual information (visual acuity and visual field conditions) on the center of pressure (COP) sway spectrum. METHODS: The subjects were 17 healthy young adults (7 males and 10 females), whose naked eye binocular visual acuity was under 0.2 (mean naked eye visual acuity: 0.1+/-0.1; mean corrected vision: 1.3+/-0.3). They participated in COP measurements under 2 kinds of visual acuity conditions (naked eye and vision correction conditions) and 3 visual field conditions (no vision: no visual information; central vision: only central visual field information; and full vision: full visual information). Spectral characteristics of COP sway of anterior/posterior (Y) and medial/lateral (X) directions were assessed using mean power frequency and frequency of maximal power (FMP). RESULTS: The Friedman test and Scheffe's pairwise comparison test showed that the FMP of posterior-anterior COP sway was higher in no vision and central vision than in the full vision condition in the vision correction condition. In the naked eye condition, there was no significant difference in any parameter between visual field conditions. CONCLUSION: In summary, although people with low visual acuity are little affected by changes of visual fields with naked eyes, with temporal vision correction they show differences in X and Y sway spectrum characteristics between visual field conditions. During vision correction, the wider their visual fields, the more low frequency sway they have. Even a temporal improvement of visual acuity may contribute to stability in an upright standing posture.