Utility of Nd isotope ratio as a tracer of marine animals : regional variation in coastal seas and causal factors

Isotopic compositions of animal tissue are an intrinsic marker commonly used to trace animal origins and migrations; however, few isotopes are effective for this purpose in marine environments, especially on a local scale. The isotope ratio of the lanthanoid element neodymium (Nd) is a promising tracer for coastal animal migrations. Neodymium derives from the same geologic materials as strontium, well known as an isotopic tracer (87Sr/86Sr) for terrestrial and anadromous animals. The advantage of the Nd isotope ratio (143Nd/144Nd, expressed as εNd) is that it varies greatly in the ocean according to the geology of the neighboring continents, whereas oceanic 87Sr/86Sr is highly uniform. This study explored the utility of the Nd isotope ratio as a marine tracer by investigating the variation of εNd preserved in tissues of coastal species, and the causes of that variation, in a region of northeastern Japan where the bedrock geology is highly variable. We measured εNd and 87Sr/86Sr in seawater, river water, and soft tissues of sedentary suspension feeders: the mussels Mytilus galloprovincialis and Mytilus coruscus and the oyster Crassostrea gigas. We also measured concentrations of three lanthanoids (La, Ce, and Pr) in shellfish bodies to determine whether the Nd in shellfish tissue was derived from solution in seawater or from suspended particulates. The εNd values in shellfish tissue varied regionally (−6 to +1), matching the ambient seawater, whereas all 87Sr/86Sr values were homogeneous and typical of seawater (0.7091–0.7092). The seawater εNd values were in turn correlated with those in the adjacent rivers, linking shellfish εNd to the geology of river catchments. The depletion of Ce compared to La and Pr (negative Ce anomaly) suggested that the Nd in shellfish was derived from the dissolved phase in seawater. Our results indicate that the distinct Nd isotope ratio derived from local geology is imprinted, through seawater, on the soft tissues of shellfish. This result underscores the potential of εNd as a tracer of coastal marine animals

Health Investigation in Takashima : On Physical Characteristics and Maximal Aerobic Power

Hight, body weight and skinfold thickness (triceps and subscapular) were measured on 48 males and 112 females living in Takashima Island. Percent body fat (% Fat) was estimated from skinfold thickness, body weight and body surface area by the equation of Nagamine. Maximal aerobic power (MAP) were estimated in 24 males and 53 females (26-72 years old) by modified Margaria\u27s method. The mean height and body weight were slightly greater than those of the Okinawa islanders, and were shown equally to the those of several rural population groups in Kyushu. The skinfold thickness and %Fat were slightly lower than those of the Okinawa islanders and several rural and urban population in Kyushu. Overall appearance rate of obesity was 2.1% in males and 24.1% in females. This male’s appearance rate was lower than that of any other Japanese groups reported, but in female the appearance rate was similar to other Japanese groups reported. The mean MAP was higher than any other Japanese groups reported in both sexes. It is suggested that Takasima islanders were unaffected by urbanization and modernization as much as people of some other regions in Kyushu

Effects of Aerobic Conditioning on Morphology and Body Composition in Middle-aged Women

Effect of aerobic conditioning on morphology and body composition were studied 33 middle-aged women (X±S. D age. 47±8.1). Exercise consisted of a 2d/wk, 12 wk aerobic conditioning (32〜59% VO2 max) accompanied by a stretching program. Before and after conditioning phase subjects were measured Body weight, 8 parts of girth, 13 parts of skinfold thickness. The parts which had highly skinfold thickness before conditioning tend to more degrease than those which had less. % Fat was estimated by 2 methods which measured skinfold thickness and Total body water. Body weights were unchanged (52.8±5.03, 52.9±4.52kg). 5 parts of girthes except arm and forearm were degreased, wherereas only calf girth was increased because of muscle hypertrophy. 12 parts of skinfold thickness except a part of cheek were also degreased. % Fat was 10% grater for the using T. B. W. method when compared to the skinfold thickness at about before and after conditioning. These findings suggest that aebobic conditioning had been caused to degrease of excess adiposity on trunk features parts and after that the differences between 2 methods in % Fat were minor. (Journal of Health Science, Kyushu University, 9: 55-61, 1987

Effects of Long-term (4 years) Aerobic Conditioning on Serum Lipids in Middle-aged Women

The purpose of this study was to investigate the changes of serum lipids through long-term aerobic conditioning in middle-aged women. Of the 17 house-wife subjects, 8 subjects (40-57 years: Group A) were participate in the aerobic conditioning program over the 4 years. The remaining 9 subjects (36-59 years: Group B) who were participated in this program for one year, were followed up for 15 and 38 months after their retirement. The aerobic conditioning program consisted of aerobic dance (35-15 minutes) and stretch exercise (15-20 minutes), respectively, two times per week. Fasting blood samples, collected 7 times for Group A and 5 times for Group B for the 4-years, were assayed for serum total cholesterol (T-ch), high density lipoprotein cholesterol (HDL-ch), Triglyceride (TG). Total lipids (T-lipid). There were no significant differences in any serum lipids between the both groups. T-ch was gradually increased and HDL-ch was gradually decreased in the course of years. Thus, HDL/T-ch ratio was increased in the course of years. No significant changes occurred for TG and T-lipids. The results of T-ch, HDL-ch and HDL/T-ch ratio conflict with those reported in many short-term training experiments. These discrepancies were probably due to the fact that the most of subjects in this study was pre-and/or post-monopausal status. Because, it is a well known fact that T-ch and HDL-ch are influenced by the menopause. Therefore, it is our conclusion that the results obtained from the short-term training experiments and younger subjects on serum lipids were not true for all, especially in middle-aged women

Physical Characteristics and Maximal Aerobic Power of the Thakali tribe living in the Western Region of Nepal

The purpose of this study was to investigate the physical characteristics and maximal aerobic power (MAP) of the Thakali tribe, which lives in the mountainous area of the Mustang district, in the Western region of Nepal. A total of 222 males and 209 females, aged from 20 to 80, participated in this study. The measurements of their physique were carried out for body height, body weight and skinfold thickness (triceps, subscapular, suprailiac, umbilical and calf). The percentage of body fat(%Fat) was calculated by the equation of Nagamine using the skinfold thickness, body weight and body surface area. MAP was estimated by Margaria\u27s indirect method. No age-group difference in the mean body height(male; 159.9±6. 0-163.4±7.3cm, female; 150.8±5.5-153.1±5.2cm) was found in this group, and these values were similar to those for other groups in the mountain areas of Nepal. The mean body weight, skinfold thickness, %Fat and the appearance rate of obesity in the male middle-aged groups were significantly larger than those of the younger groups. Although the energy intake per day in this group was lower than that for other rural groups in Nepal, the %Fat and the appearance rate of obesity in the middle-aged were higher than those of the rural groups and were similar to those of the sedentary group in Nepal. In females, no significant differences in the mean body weight, skinfold thickness, (%h~at or the appearance rate of obesity were found between the Thakali tribe and other groups of mountain villagers, but the rates were higher than in other rural groups in Nepal. The mean MAPS of the Thakali males were almost at the same levels as those of the rural group of the Nepal in all age groups, but those in the younger female group were lower than those of the rural groups. It is thus considered that the fatty body composition in the aged male group and lower physical fitness in the younger female group may be due to their physically inactive lifestyle, professions as hotel owner, shopkeeper or shop assistant, etc.ネパール上国のWesten Region, Mustang DistrictのTukucheおよびMurpha村を中心とする20歳以上のタカリ族の男性222名，女性209名の形態および推定最大酸素摂取量(MAP)を調査した。これらの調査値を1981年の同地区の調査値および他の地区住民の調査値と比較して検討した。1)身長は男女とも世代差が認められず，1981年の調査値とも差が認められなかった。約10年間の間に住民の社会経済的変化は起こっているであろうが，その変化は，身長に影響を与えるほど大きな変化ではないと考えられた。そしてタカリ族の身長は，チベット系住民やシェルパ族とも差がないと思われる。2)体重，皮下脂肪厚，体脂肪率および肥満者の出現率は，1981年に比べ多くなっていた。また男性では，若年に比べて中高年者が大きい傾向にあった。そしてこれらの値は，男性ではチベット難民キャンプの住民と，女性ではネパール北東部のシェルパ族とほぼ同様であった。摂取エネルギーは必ずしも多くないにも関わらず，体重や体脂肪などは自給自足的な丘陵地農民や都市近郊農民より大きかった。3)男性のMAPは必ずしも低くなく，シェルパ族や丘陵地農民と大差が認められなかった。女性では世代間のMAPの差は大きくなく，それは20歳代の低体力化の影響によると考えられた。20歳代の値は，座業的なチベット難民キャンプの20歳代や日本人と大差が認められず，他のネパール集団のそれより低かった