Search

Rungthip Puntumetakul,1,2 Thavatchai Suvarnnato,1,3 Phurichaya Werasirirat,1 Sureeporn Uthaikhup,2 Junichiro Yamauchi,4,5 Rose Boucaut6 1School of Physical Therapy, Faculty of Associated Medical Sciences, 2Research Center in Back, Neck, Other Joint Pain and Human Performance, 3Physical Therapy Unit, Srinagarind Hospital, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; 4Graduate School of Human Health Sciences, Tokyo Metropolitan University, 5Future Institute for Sport Sciences, Tokyo, Japan; 6School of Health Sciences (Physiotherapy), University of South Australia, Adelaide, SA, Australia Background: Thoracic spine manipulation has become a popular alternative to local cervical manipulative therapy for mechanical neck pain. This study investigated the acute effects of single-level and multiple-level thoracic manipulations on chronic mechanical neck pain (CMNP).Methods: Forty-eight patients with CMNP were randomly allocated to single-level thoracic manipulation (STM) at T6–T7 or multiple-level thoracic manipulation (MTM), or to a control group (prone lying). Cervical range of motion (CROM), visual analog scale (VAS), and the Thai version of the Neck Disability Index (NDI-TH) scores were measured at baseline, and at 24-hour and at 1-week follow-up.Results: At 24-hour and 1-week follow-up, neck disability and pain levels were significantly (P

Rungthip Puntumetakul,1 Wantanee Yodchaisarn,1 Alongkot Emasithi,2 Petcharat Keawduangdee,1 Uraiwan Chatchawan,1 Junichiro Yamauchi3 1The Research Center in Back, Neck, Other Joint Pain and Human Performance (BNOJPH), Khon Kaen University, Khon Kaen, Thailand; 2School of Physical Therapy, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand; 3Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan Introduction: Clinical lumbar instability (CLI) is one of the subgroups of chronic non-specific low back pain. Thai rice farmers often have poor sustained postures during a rice planting process and start their farming at an early age. However, individual associated factors of CLI are not known and have rarely been diagnosed in low back pain. This study aimed to determine the prevalence and individual associated factors of CLI in Thai rice farmers. Methods: A cross-sectional survey was conducted among 323 Thai rice farmers in a rural area of Khon Kaen province, Thailand. Face-to-face interviews were conducted using the 13-item Delphi criteria questionnaire, after which an objective examination was performed using aberrant movement sign, painful catch sign, and prone instability test to obtain information. Individual factors such as sex, body mass index, waist-hip ratio, smoking, and number of years of farming experience, were recorded during the face-to-face interview. Results: The prevalence of CLI in Thai rice farmers calculated by the method described in this study was 13% (age 44±10 years). Number of years of farming experience was found to be significantly correlated with the prevalence of CLI (adjusted odds ratio =2.02, 95% confidence interval =1.03–3.98, P

Rungthip Puntumetakul,1,2 Pattanasin Areeudomwong,1,2 Alongkot Emasithi,1 Junichiro Yamauchi3,4 1School of Physical Therapy, Faculty of Associated Medical Sciences, Muang District, Kohn Kaen, Thailand; 2Back, Neck and Other Joint Pain Research Group, Khon Kaen University, Khon Kaen, Thailand; 3Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan; 4Future Institute for Sport Sciences, Tokyo, Japan Background and aims: Clinical lumbar instability causes pain and socioeconomic suffering; however, an appropriate treatment for this condition is unknown. This article examines the effect of a 10 week core stabilization exercise (CSE) program and 3 month follow-up on pain-related outcomes in patients with clinical lumbar instability. Methods: Forty-two participants with clinical lumbar instability of at least 3 months in duration were randomly allocated either to 10 weekly treatments with CSE or to a conventional group (CG) receiving trunk stretching exercises and hot pack. Pain-related outcomes including pain intensity during instability catch sign, functional disability, patient satisfaction, and health-related quality of life were measured at 10 weeks of intervention and 1 and 3 months after the last intervention session (follow-up); trunk muscle activation patterns measured by surface electromyography were measured at 10 weeks. Results: CSE showed significantly greater reductions in all pain-related outcomes after 10 weeks and over the course of 3 month follow-up periods than those seen in the CG (P

When a conducting shallow cavity is placed behind an equiangular spiral to obtain a unidirectional beam, the inherent wideband characteristics of the spiral deteriorate. To restore the wideband characteristics, a ring-shaped absorbing strip (R-ABS) is placed under the spiral arms. Analysis of the equiangular spiral with the R-ABS is performed using the finitedifference time-domain method. It is found that the R-ABS successfully restores the wideband characteristics. Subsequently, the R-ABS is divided into two absorbing strips, each specified by an arc-angle [[phi].sub.ARC]. Analysis reveals that the radiation characteristics obtained using the R-ABS are reproduced when the arc-angle is greater than [[phi].sub.ARC] = 90[degrees]. Throughout this paper an extremely small cavity depth is selected for the analysis: 0.07 wavelength at the lower operating design frequency of 3 GHz. Index Terms--Absorbing strips, cavity, equiangular spiral, wideband characteristics.

An antenna composed of a conducting body of revolution (BOR) and a parasitic ring shorted to a finite-sized ground plate, designated as the BOR-SPR, is designed for realizing a low-profile base station antenna with a wideband voltage standing wave ratio (VSWR) characteristic. The design of the BOR-SPR starts with a center-fed patch antenna. To match the antenna input impedance to a 50-ohm feed line, as a first step, a slot is cut into the patch (this antenna is designated as Ant-I), and as a second step, shorted parasitic conducting pins are added to the periphery of Ant-I (this antenna is designated as Ant-II). Ant-II has a VSWR bandwidth of approximately 28%. Further increase in the VSWR bandwidth is achieved by replacing the inner feed region of Ant-II with a conducting BOR. It is found that this replacement, creating the BOR-SPR, yields an extremely wide VSWR bandwidth of approximately 147%, where the electrical antenna height at the lower edge frequency of the bandwidth is small: approximately 0.07 wavelength. It is also found that the radiation pattern of the BOR-SPR is similar to that of a monopole above a finite-sized ground plate. The beam direction 0 (measured from the direction normal to the surface of the BOR) varies between approximately 30[degrees] and 60[degrees]. The gain at [theta] = 60[degrees] is approximately 2 dBi near the lower edge frequency of the VSWR bandwidth and approximately 8 dBi near the upper edge frequency. Index Terms--Body of revolution (BOR), finite-difference time-domain (FDTD) analysis, shorted ring, wideband antenna.

This paper describes the radiation characteristics of crank-line antennas radiating a circularly polarized wave. First, the radiation efficiency versus substrate permittivity is evaluated. Second, a 12-cell crank-line antenna of substrate permittivity [[Epsilon].sub.r] = 1 and antenna height B = [[Lambda].sub.11.85]/8 is investigated as a reference antenna, where [[Lambda].sub.11.85] is the wavelength at a frequency of 11.85 GHz. It is found that the main beam direction of the reference antenna varies 7 [degrees] over a frequency range of approximately 6%, with an axial ratio of less than 3 dB and a gain of approximately 21 dB. Third, attention is paid to the gain behavior versus the antenna height. A way to increase the gain by modifying the antenna height is proposed. An increase of 1.5 dB from the gain of the reference antenna is demonstrated. Finally, the axial ratio, gain, and decoupling factor for crank-line antenna arrays are presented and discussed. Index Terms - Antenna measurements, antenna theory.

A radiation element, designated as a curl antenna, is proposed for a circularly polarized antenna. The radiation characteristics of the curl are numerically analyzed. The gain is approximately 8.4 dB, and the 3-dB axial ratio criterion is 6.7%. Two aspects of curl array antennas are also presented: a decoupling factor between two curls and a circular array antenna consisting of 168 curls. Calculations show how the decoupling factor depends on the relative rotation angle of the two curls. The 168-curl array antenna shows a high aperture efficiency of 95%.