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The article presents a study on the fluxes of sensible and latent heat in Pasoh Forest Reserve low-land diptecrocarp forest in Peninsular Malaysia. The study conducted observations in the said forest reserve with various considerations including canopy height, plant area index, and altitude of core area. Results show that sensible heat flux fluctuates depending on the fluctuation of radiation in wet and dry season. It adds that excess water loss was due to decreased midday surface conductance.

Ambient CO2 concentration, air temperature and relative humidity were measured intermittently for a 3-year period from the floor to the canopy top of a tropical rainforest in Pasoh, Peninsular Malaysia. Mean diurnal CO2 storage flux ( Sc; μmol m−2 s−1) and sensible and latent heat storage fluxes ( Qa and Qw; W m−2) ranged from −12.7 to 3.2 μmol m−2 s−1, −15 to 27 W m−2 and −10 to 20 W m−2, respectively. Small differences in diurnal changes were observed in Sc and Qa between the driest and wettest periods. Compared with the ranges of mean diurnal CO2 eddy flux (−14.7 to 4.9 μmol m−2 s−1), sensible eddy flux (−12 to 169 W m−2) and latent eddy flux (0 to 250 W m−2), the contribution of CO2 storage flux was especially large. Comparison with summertime data from a temperate Japanese cypress forest suggested a higher contribution of Sc in the tropical rainforest, probably mainly due to the difference in nighttime friction velocity at the sites. On the other hand, differences in Qa and Qw were smaller than the difference in Sc, probably because of the smaller nighttime sinks/sources of heat and water vapour. [ABSTRACT FROM AUTHOR]

Seasonal fluctuations in leaf gas exchange parameters were investigated in three evergreen (Quercus glauca Thunb., Cinnamomum camphora Sieb. and Castanopsis cuspidata Schottky) and one deciduous (Quercus serrata Thunb.) co-occurring, dominant tree species in a temperate broad-leaved forest. Dark respiration rate (Rn), maximum carboxylation rate (Vcmax) and stomatal coefficient (m), the ratio of stomatal conductance to net assimilation rate after adjustment to the vapor pressure deficit and internal carbon dioxide (CO2) concentration, were derived inversely from instantaneous field gas exchange data (one-point method). The normalized values of Rn and Vcmax at the reference temperature of 25 °C (Rn25, Vcmax25) and their temperature dependencies (ΔHa(Rn), ΔHa(Vcmax)) were analyzed. Parameter Vcmax25 ranged from 24.0–40.3 μmol m−2 s−1 and ΔHa(Vcmax) ranged from 29.1–67.0 kJ mol−1. Parameter Rn25 ranged from 0.6–1.4 μmol m−2 s−1 and ΔHa(Rn) ranged from 47.4–95.4 kJ mol−1. The stomatal coefficient ranged from 7.2–8.2. For the three evergreen trees, a single set of Vcmax25 and Rn25 parameters and temperature dependence curves produced satisfactory estimates of carbon uptake throughout the year, except during the period of simultaneous leaf fall and leaf expansion, which occurs in April and May. In the deciduous oak, declines in Vcmax25 were observed after summer, along with changes in Vcmax25 and Rn25 during the leaf expansion period. In all species, variation in m during periods of leaf expansion and drought should be considered in modeling studies. We conclude that the changes in normalized gas exchange parameters during periods of leaf expansion and drought need to be considered when modeling carbon uptake of evergreen broad-leaved species. [ABSTRACT FROM PUBLISHER]

The bilateral sagittal split osteotomy (BSSO) has evolved into an effective and preferred surgical procedure for mandibular setbacks. As with all surgical procedures designed to setback the mandible, relapse occasionally occurs after BSSO procedures. Several factors have been suggested to play a contributory role in this relapse. The present study was performed to determine the stability of the mandibular position over the course of long-term observation. Different facial patterns that could potentially be used as predictors of relapse were examined. The study included cases of skeletal mandibular prognathism, with the patient in each case having undergone surgical correction involving a BSSO at least 5 years prior to the study. Lateral cephalograms were analyzed in order to classify facial patterns. Angular and linear cephalometric measurements, consisting of SN-Pogonion angle, SN-occlusal plane angle, and Pogonion depth and height, were compared at 1 year postoperatively and at the long-term follow-up. A significant correlation between facial type and relapse pattern was confirmed at the long-term assessment of prognosis. [ABSTRACT FROM AUTHOR]

Abstract: The eddy covariance method was used to observe carbon dioxide flux (F c) for 3 years over an old-growth tropical rainforest at Pasoh in Peninsular Malaysia. The average nighttime F c and NEE were 3.6 and 4.7μmolm−2 s−1, respectively, when friction velocity (u * )≥0.2, while the average soil respiration rate measured occasionally with the chamber method was estimated to be 4.1μmolm−2 s−1 if we used the relationship between volumetric soil water content, or 3.8μmolm−2 s−1 if we used the pure average of nine observations. The comparison of F c, NEE and soil respiration strongly suggests that nighttime CO2 efflux was underestimated even when the CO2 storage term is considered. The correction of F c data for low u * did not correct this underestimate, and it was strongly suggested that this forest was not a strong carbon sink, as raw F c data, even with the u * filtering, implied. Monthly average daytime diurnal changes in CO2 exchange over the canopy were fairly constant from 2003 to 2005 despite fluctuations in soil moisture, solar radiation, air temperature and vapor pressure deficit between dry and wet periods. An obvious inhibition of canopy CO2 exchange in the afternoon coupling with increases in VPD and air temperature was observed year-round. In the case of nighttime NEE, a slight increase in wet period was observed. Diurnal pattern of CO2 exchange revealed that obvious restriction of canopy photosynthesis in the afternoon was occurred in this forest irrespective of soil moisture. Seasonal and annual patterns of CO2 exchange reveal that one of the main causes which induce the difference in NEE pattern between Amazonian and Southeast Asian rainforests was not the difference in daytime photosynthesis but the difference in ecosystem respiration related with dry and rainy seasons. The decrease of CO2 uptake (increase of NEE) at wet period was also observed at this site, but did not form an obvious seasonality such as in Amazonian forests. [Copyright &y& Elsevier]

Purpose: We investigated the incidence of prostaglandin-associated periorbitopathy (PAP) in subjects with glaucoma treated with latanoprost ophthalmic solution., Subjects and Methods: One eye and the forehead in 22 subjects were evaluated. All patients had used latanoprost for more than 1 year (range, 12 to 45 months; mean, 26.0 months) and were prostaglandin F2α analogue treatment-naïve. Digital photographs of the subjects obtained before latanoprost therapy and at the last examination were compared retrospectively. Four signs of PAP (deepening of the upper eyelid sulcus (DUES), upper eyelid ptosis, flattening of the lower eyelid bags, and inferior scleral show) and supplemental side effects around the eyelids (eyelash growth, poliosis, and eyelid pigmentation) were judged to be negative or positive by three independent observers. If the observers unanimously rated a sign as positive, the result was defined as positive., Results: Twelve subjects (54.5%) had no apparent signs. Three subjects were judged to have DUES (13.6%), and two subjects each were judged to have flattening of the lower eyelid bags and eyelid pigmentation (9.0%). The other signs were judged as positive in only one subject each, respectively (4.5%). A univariate logistic regression analysis showed no significant associations between any of the signs and age, sex, or the duration of therapy., Conclusion: Latanoprost induced DUES, upper eyelid ptosis, flattening of the lower eyelid bags, inferior scleral show, and supplemental side effects around the eyelids; however, the rates of such occurrence might be relatively low.