Relationship between psychosomatic complaints and circadian rhythm irregularity assessed by salivary levels of melatonin and growth hormone

<p>Abstract</p> <p>Background</p> <p>In university health care settings, students with psychosomatic complaints often have chronotypic problems. For this reason, we investigated a potential connection between psychosomatic complaints and circadian rhythm irregularity assessed by salivary levels of melatonin and growth hormone.</p> <p>Methods</p> <p>Fifteen healthy students between 21 and 22 years of age were examined for physiological parameters of chronotypes based on melatonin and growth hormone secretion patterns, using a fluorescence enzyme immunoassay. Salivary samples were collected from subjects at home five times each day (20:00, 24:00, 04:00, 08:00, and 12:00 h). In addition, the subjects rated their psychosomatic symptoms twice (at 08:00 and 20:00 h).</p> <p>Results</p> <p>A group with irregular circadian rhythm of melatonin (ICR) showed more psychosomatic complaints than a group with the regular circadian rhythm (RCR), especially for anxiety.</p> <p>Conclusion</p> <p>Psychosomatic symptoms, particularly anxiety, may be associated with irregularity in melatonin and growth hormone rhythms, which can be altered by basic lifestyle habits even in healthy students.</p

Dilatonic Inflation and SUSY Breaking in String-inspired Supergravity

The theory of inflation will be investigated as well as supersymmetry breaking in the context of supergravity, incorporating the target-space duality and the nonperturbative gaugino condensation in the hidden sector. We found an inflationary trajectory of a dilaton field and a condensate field which breaks supersymmetry at once. The model satisfies the slow-roll condition which solves the eta-problem. When the particle rolls down along the minimized trajectory of the potential V(S,Y) at a duality invariant point of T=1, we can obtain the e-fold value \sim 57. And then the cosmological parameters obtained from our model well match the recent WMAP data combined with other experiments. This observation suggests one to consider the string-inspired supergravity as a fundamental theory of the evolution of the universe as well as the particle theory.Comment: 10 pages, 4 eps figures. Typos and references corrected. Final version to appear in Mod. Phys. Lett.

Angular Power Spectrum in Modular Invariant Inflation Model

We propose a scalar potential of inflation, motivated by modular invariant supergravity, and compute the angular power spectra of the adiabatic density perturbations that result from this model. The potential consists of three scalar fields, S, Y and T, together with two free parameters. By fitting the parameters to cosmological data at the fixed point T=1, we find that the potential behaves like the single-field potential of S, which slowly rolls down along the minimized trajectory in Y. We further show that the inflation predictions corresponding to this potential provide a good fit to the recent three-year WMAP data, e.g. the spectral index n_s = 0.951. The TT and TE angular power spectra obtained from our model almost completely coincide with the corresponding results obtained from the \LambdaCDM model. We conclude that our model is considered to be an adequate theory of inflation that explains the present data, although the theoretical basis of this model should be further explicated.Comment: 8 pages, 8 figures and 1 tabl

A possible connection between psychosomatic symptoms and daily rhythmicity in growth hormone secretion in healthy Japanese students

<p>Abstract</p> <p>Background</p> <p>Students suffering from psychosomatic symptoms, including drowsiness and feelings of melancholy, often have basic lifestyle problems. The aim of this study was to investigate whether psychosomatic complaints may be related to circadian dysfunction.</p> <p>Methods</p> <p>We examined 15 healthy students (4 men and 11 women) between 21 and 22 years old. To assess the presence of psychosomatic symptoms among the subjects, we developed a self-assessment psychosomatic complaints questionnaire consisting of five items pertaining to physical symptoms and five items concerning mental symptoms. The subjects rated their psychosomatic symptoms twice a day (08:00 and 20:00 h). We also assessed growth hormone secretion patterns by fluorescence enzyme immunoassay (FEIA). Salivary samples were collected from the subjects at home five times a day (20:00, 24:00, 04:00, 08:00, and 12:00 h) in Salivette tubes.</p> <p>Results</p> <p>The results indicated a relationship between the self-assessment scores and the salivary levels of growth hormone. Subjects with high self-assessment scores showed significant variability in growth hormone secretion over the day, whereas subjects with low self-assessment scores did not.</p> <p>Conclusion</p> <p>Psychosomatic symptoms may be associated with circadian dysfunction, as inferred from blunted rhythmicity in growth hormone secretion.</p

Distribution of chlorophyll-a and sea surface temperature in the marginal ice zone (20°E-60°E) in East Antarctica determined using satellite multi-sensor remote sensing during austral summer

We investigated the distribution of chlorophyll-a (Chl-a) and sea surface temperature (SST) off the sea ice region south of 64°S in East Antarctica between 20°E and 60°E during austral summers, 1998-2002. We used satellite multi-sensor remote sensing datasets including ocean color Chl-a, SST and sea ice concentration. High concentrations of Chl-a (>0.5 mg m^(-3)) were generally observed in colder water below 0°C. Phytoplankton blooms were extended into shallow areas along the isobath. SST distribution exhibited two patterns. In the first pattern, warm water located to the north of this region associated with polynya in early spring. The second pattern was characterized by distribution of cold water throughout the study area. A shift of the Antarctic Circumpolar Current (ACC) is considered to affect this difference between SST distributions. The cold water from the Antarctic coastal current mixed with meltwater was expected to provide vertical stability of the water column for phytoplankton blooms. These results suggest that the phytoplankton blooms in this study area during austral summer can be attributed to water conditions affected by melting sea ice, movement of the ACC and sea floor topography

Acclimation of photosynthetic properties in psychrophilic diatom isolates under different light intensities

Acclimation of growth and photosynthetic properties was examined for diatom strains, isolated from Saroma Ko lagoon (44°N, 144°E) in early spring, under different light intensities at 1℃. The relatively high specific growth constants under low irradiances were recognized for both Chaetoceros sp. and Thalassiosira sp. Further examination of photosynthesis in Chaetoceros sp. showed that growth under low irradiance caused an increase in the photosynthetic effciency for Chl α-specific rate of gross O_2 evolution (α^B) and a decrease in the Chl α-specific rate of dark O_2 respiration (R_d^B), which was extrapolated from the initial slope of net O_2 evolution rate vs. irradiance curve. These changes explain the low light compensation point for net photosynthetic O_2 evolution (I_c) and the high efficiency for growth under low irradiance conditions. Neither Chl α-specific amounts of light-harvesting pigments, such as fucoxanthin and Chl c, nor cellular content of Chl α, but Chl α-specific amount of diadinoxanthin was varied by the change in irradiance condition. The increase of α^B under low growth irradiance corresponded with a decrease in the amount of diadinoxanthin relative to Chl α. However, the Chl α-specific maximum photosynthetic rate (P_m^B) was retained at the same level and photoinhibition could not be observed under illumination up to &acd;800μE m^ s^. The light intensity at which photosynthesis was light-saturated (I_k, =P_m^B/α^B) was much higher than the incident growth irradiances (76 and 88μE m^ s^ under the growth irradiances of 11 and 42 μE m^ s^, respectively), although the value of I_k for the former was significantly smaller (t-test, P<0.001) than that for the latter. Thus, the capacity of photochemical reaction around photosystems seems to remain large even under low irradiance. These properties may indicate that the diatom cells could efficiently utilize light-energy under large variation of irradiance even on a short time-scale