Responses of Etiella zinckenella to habitat fragmentation of Caraganas in desert steppe in Ningxia, China

Habitat fragmentation is a common cause for which species becomes threatened or endangered. Existence of viable habitat is critical to the survival of any species, so habitat fragmentation is the main reason for the changes in distribution and abundance of organisms, and is usually considered to have negative effect on the abundance, species richness and population of organisms in a specific landscape. But this effect may also depend on whether some species could use one or more types of habitat in a specific landscape. Because of its well resistance to stress, Caragana is one of predominant shrub in desert region for forest planting and desert preventing, which plays a critical role in desert control and ecosystem stabilization. Baijitan National Nature Reserve, located in Lingwu County, Ningxia Hui Autonomous Region, China, is typical of desert nature reserve in which the Caragana spp., Oxytropis aciphylla and other desert plants are protected. The Caragana woodlands in this region show a pattern of dots, patches and strips separated by natural and cultivated forest, thereby leading to a typical fragmented landscape. Etiella zinckenella (Lepidoptera, Pyralidae) is one of seed pests of Caragana. In order to illuminate the responses of E. zinckenella to the habitat fragmentation of Caraganas woodlands, the present study focused on the effects of habitat area, habitat fragmentation, as well as matrix composition on the population density and damage ratio of E. zinckenella in desert steppe. From May 2008 to June 2009, by using parallel jump sampling method, 13 Caragana woodland patches representing four landscapes from Baijitan National Nature Reserve were investigated and totally 15,117 pods were inspected. Then, the landscape fragmentation indices, population density and damage ratio of E. zinckenella in Caragana woodlands were calculated. The statistic analysis of the data indicated that the four landscapes have a significant difference in the population density and damage ratio of E. zinckenella; and in the same landscape, the neighbor patches also have a significant difference in the damage ratios of E. zinckenella. E. zinckenella seems to prefer some species of Caragana, for instance, the damage ratio of E. zinckenella to Caragana microphylla is found the highest, followed by the damage ratio to Caragana davazamcidamage, while the damage ratio to Caragana korshinskii is found the lowest. The coverage of Caragana is found positively related to the damage ratio of E. zinckenella with hinge damage ratio in high coverage of Caragana forest. The regression analysis shows that the latitude (R_s = 0.5724), longitude (R_s = 0.5577), altitude (R_s = 0.4614) and patch area (R = 0.3012) were not significantly associated with population density and damage ratio of E. zinckenella. However, the population density and damage ratio of E. zinckenella decreased with the increasing in patch area. The landscape patch fragmentation index (R = 0.91129) and the patch density index (R = 0.89864) show a positive correlation with damage ratio. The fragmentation shape index (R = ?0.89675) and inside habitat area fragmentation index (R = ?0.77646) show a negative correlation with the damage ratio. As a result, the population of E. zinckenella was suppressed by the landscape fragmentation, but the patch isolation and complementary resources in the landscape matrix may also have a positive impact on the population density of E. zinckenella.     

Assessment of rabbit hemorrhagic disease in controlling the population of red fox: A measure to preserve endangered species in Australia

Predator's management requires a detailed understanding of the ecological circumstances associated with predation. Predation by foxes has been a significant contributor to the Australian native animal reduction. This paper mainly focuses on the dissemination of rabbit hemorrhagic disease in the rabbit population and its subsequences on red fox (Vulpes vulpes) population, by qualitative and quantitative analyses of a designed eco-epidemiological model with simple law of mass action and sigmoid functional response.Existence of solution has been analyzed and shown to be uniformly bounded. The basic reproduction number (R₀) is obtained and the occurrence of a backward bifurcation at R₀ = 1 is shown to be possible using central manifold theory. Global stability of endemic equilibrium is established by geometric approach. Criteria for diffusion-driven ecological instability caused by local random movements of European rabbits and red fox are obtained. Detailed analyses of Turing patterns formation selected by reaction-diffusion system under zero flux boundary conditions are presented. We found that transmission rate, self and cross-diffusion coefficients have appreciable influence on spatial spread of epidemics. Numerical simulation results confirm the analytical finding and generate patterns which indicate that population of red foxes might be controlled if rabbit hemorrhagic disease (RHD) is introduced into the rabbit population and thus ecological balance can be maintained.     

Effects of shell morphological traits on the weight traits of Manila clam (Ruditapes philippinarum)

The shell length, height, and width, live body weight, and edible tissue weight of Manila clam of 1, 2, and 3 years of age were measured, and their correlation coefficients were calculated. The shell morphological traits were used as independent variables, and live body weight or edible tissue weigh used as a dependent variable for calculating the path coefficients, correlation index and determination coefficients. The results showed that the correlation coefficients between each shell morphological trait and the live body weight or edible tissue weight were all highly significant (P < 0. 01). The shell height at 1-year old clams was highly correlated with the live body weight and edible tissue weight. The shell width of 2- to 3-year-old clams was strongly associated with the live body weight, while the shell length was closely linked to the edible tissue weight. The results of coefficients of determination for the morphological traits against weight traits agreed well with the results of path analysis. The correlation indices for all morphological traits against weight traits were approximately the same as determination coefficients regardless of clam age. The correlation indices (R²) of morphological traits against the live body weight of clams of all ages and edible tissue weight of 1-year-old clams were larger than 0.85, but R² of morphological traits against the edible tissue weight of 2- and 3-year-old clams was smaller than 0.85, indicating that some other factors might be associated with the edible tissue weight of 2- and 3-year-old clams. Multiple regression equations were obtained to estimate shell length X₁ (cm), shell height X₂ (cm), shell width X₃ (cm) against live body weight Y (g), edible tissue weight Z (g): for 1-year-old clams: Y = ?4.317 + 0.18X₁ + 0.147X₂, (X₁ < 0.01, X₂ < 0.01), Z = ?1.011 + 0.095X₂, (X₂ < 0.01); for 2-year-old clams: Y = ?15.119 + 0.249X₁ + 0.176X₂ + 0.688X₃, (X₁ < 0.01, X₃ < 0.01), Z = ?4.248 + 0.198X₁, (X₁ < 0.05, X₃ < 0.01); and for 3-year-old clams: Y = ?25.013 + 0.415X₁ + 1.184X₃, (X₁ < 0.01, X₃ < 0.01), Z = ?7.082 + 0.119X₁ + 0.332X₃, (X₁ < 0.05, X₃ < 0.01).     

N-1 and C-3 substituted indole Schiff bases as selective COX-2 inhibitors: synthesis and biological evaluation

A group of N-1 and C-3 disubstituted-indole Schiff bases bearing an indole N-1 (R′ = H, CH₂Ph, COPh) substituent in conjunction with a C-3 –CHN–C₆H₄–4-X (X = F, Me, CF₃, Cl) substituent were synthesized and evaluated as inhibitors of cyclooxygenase (COX) isozymes (COX-1/COX-2). Within this group of Schiff bases, compounds 15 (R¹ = CH₂Ph, X = F), 17 (R¹ = CH₂Ph, X = CF₃), 18 (R¹ = COPh, X = F) and 20 (R¹ = COPh, X = CF₃) were identified as effective and selective COX-2 inhibitors (COX-2 IC₅₀’s = 0.32–0.84 μM range; COX-2 selectivity index (SI) = 113 to >312 range). 1-Benzoyl-3-[(4-trifluoromethylphenylimino)methyl]indole (20) emerged as the most potent (COX-1 IC₅₀ >100 μM; COX-2 IC₅₀ = 0.32 μM) and selective (SI >312) COX-2 inhibitor. Furthermore, compound 20 is a selective COX-2 inhibitor in contrast to the reference drug indomethacin that is a potent and selective COX-1 inhibitor (COX-1 IC₅₀ = 0.13 μM; COX-2 IC₅₀ = 6.9 μM, COX-2 SI = 0.02). Molecular modeling studies employing compound 20 showed that the phenyl CF₃ substituent attached to the CN spacer is positioned near the secondary pocket of the COX-2 active site, the CN nitrogen atom is hydrogen bonded (N?NH = 2.85 Å) to the H90 residue, and the indole N-1 benzoyl is positioned in a hydrophobic pocket of the COX-2 active site near W387.     

A study on multidimensional time series model of individual age’s measurement in Castanopsis kawakamii population

Studies on disclosing characteristics and endangered mechanisms of Castanopsis kawakamii population ecology have already become an urgent task of protecting C. kawakamii population. The establishment of the standard life table is one of an important work study on C. kawakamii population ecology, and determining individual ages of the plant is necessary for studying age structures and population dynamics of C. kawakamii. There are three main methods of determining individual age of forest population: (1) by annual ring of tree, (2) by individual growth phase, and (3) by DBH and height of tree. However, the three methods have their shortcomings, such as low precision, worse serviceability, high difficulty for operation and so on. In this paper, a new method for determining plant individual ages more accurately is presented on the basis of the method aboU_t “annual ring–time series”. Based on the stem analysis, the multidimensional time series model of diameter growth at breast height in C. kawakamii population was established by U_tilizing the analY_tical method of multidimensional time series: Y_t = 1.325034Y_t-1 ? 0.4711007Y_t-2 ? 284.5648U_t + 569.4783U_t?1 ? 284.8745U_t?2, where Y_t, Y_t-1, Y_t-2 represent diameter growth in C. kawakamii population at t, t ? 10 and t ? 20 years respectively, and U_t, U_t?1, U_t?2 represent individual age in C. kawakamii population at t, t ? 10 and t ? 20 years respectively, the model coefficient correlation is 0.9994. Based on this model CAR(2), the total increment of individual DBH in C. kawakamii population are simulated and regressively verified at different ages. The mean simulating precision of this model was 98.84%, the maximum relative error was 2.56%, bU_t the next was 2.47% and the minimum relative error was 0.07%, showing that this model was suitable for estimating breast-height diameter of C. kawakamii plant. Using the multidimensional time series model, diameter growth of C. kawakamii population for longer time series was estimated in order to gain data for establishing the relationship model of individual age, diameter growth and to increase its precision in determining individual age is by tree ring analysis. A combination method of determining individual age of C. kawakamii population by integrating annual ring data with its diameter using multidimensional time series model, which can improve precision of individual ages in C. kawakami, was produced: A = 9.966671944 + 1.146011591D + 0.041059628D² ? 0.000211907D³, where A and D represent individual age and diameter at breast height respectively in C. kawakamii population, the model coefficient correlation is 0.9998. The combination model, which shows that the regression relationship is significant and the model can exactly predict the individual age of population, is a valuable tool for determining individual ages in endangered plants.     

The perioperative granulocyte/lymphocyte ratio is a clinically relevant marker of surgical stress in patients with colorectal cancer

PurposeThis study was to assess the clinical relevance of the blood granulocytes to lymphocytes (G/L) ratio as an early marker of surgical stress in patients with colorectal cancer.MethodsThirty-three patients with colorectal cancer were prospectively to undergo laparoscopic-assisted (n = 12) or open (n = 21) surgical resection. Granulocyte and lymphocyte counts were used to calculate the G/L ratios in blood samples from all patients before the operation and post-operatively on days 1, 3 and 7. Additionally, serum inflammatory cytokines, interleukin (IL)-1β, IL-6, IL-8, tumour necrosis factor (TNF)-α, granulocyte colony-stimulating factor (G-CSF) and macrophage (M)-CSF were assayed as markers of surgical stress.ResultsSeven of 33 patients developed unexpected complications. Serum IL-6 (P < 0.0001), G-CSF (P = 0.0257), and M-CSF (P < 0.0001) were higher on day 1 vs before the operation. Similarly, the G/L ratios were higher on days 1–3 vs before the operation (P < 0.0001) and then gradually decreased together with the surgical stress levels. The G/L ratios and the numbers of granulocytes and lymphocytes in the blood showed no correlation with serum IL-1β or TNF-α. In contrast, the G/L ratios and the numbers of granulocytes in the blood showed significant correlation with IL-6 (Rs = 0.710, P < 0.0001, Rs = 0.653, P < 0.0001, respectively), with G-CSF (Rs = 0.626, P < 0.0001, Rs = 0.578, P < 0.0001), with M-CSF (Rs = 0.470, P < 0.0001, Rs = 0.372, P < 0.0001). However, the number of lymphocytes showed inverse correlation with IL-6 (Rs = ?0.493, P < 0.0001), G-CSF (Rs = ?0.440, P < 0.0001) and M-SCF (Rs = ?0.443, P < 0.0001).ConclusionThe G/L ratio appears to be a simple and clinically relevant parameter for the assessment of perioperative stress in patients undergoing colorectal surgery.     

Comparison of the life tables and predation rates of Harmonia dimidiata (F.) (Coleoptera: Coccinellidae) fed on Aphis gossypii Glover (Hemiptera: Aphididae) at different temperatures

The life histories and predation rates of the ladybird beetle Harmonia dimidiata (F.) were compared among beetles kept at 15, 20, and 25 °C. The beetles were fed on Aphis gossypii Glover and were maintained at 70 ± 10% RH and a 14:10 (L:D) h photoperiod. According to the age-stage, two-sex life table, the net reproductive rates (R₀) were 147.4, 98.7, and 62.5 offspring for beetles kept at 15, 20, and 25 °C, respectively. Additionally, we employed both the jackknife and bootstrap techniques for estimating the means, variances, and standard errors of the population parameters. The sample means of R₀ and the other population parameters obtained using the bootstrap technique fit a normal distribution, but the jackknife technique generated biologically meaningless zero values for R₀. The net predation rates were 10963, 13050, and 7492 aphids for beetles kept at 15, 20, and 25 °C, respectively. For a comprehensive comparison of predation potential, we incorporated both the finite rate and the predation rate into the finite predation rate. When both the growth rate and the predation rate were considered, our results showed that H. dimidiata is a more efficient biological control agent for A. gossypii at 20 and 25 °C than at 15 °C.     

Effects of dwarf bamboo (Fargesia denudata) density on biomass, carbon and nutrient distribution pattern

Dense dwarf bamboo population is a structurally and functionally important component in many subalpine forest systems. To characterize the effects of stem density on biomass, carbon and majority nutrients (N, P, K, Ca and Mg) distribution pattern, three dwarf bamboo (Fargesia denudata) populations with different stem densities (Dh with 220 ± 11 stems m^?2, Dm with 140 ± 7 stems m^?2, and Dl with 80 ± 4 stems m^?2, respectively) were selected beneath a bamboo-fir (Picea purpurea) forest in Wanglang National Nature Reserve, Sichuan, China. Leaf, branch, rhizome, root and total biomass of dwarf bamboo increased with the increase of stem density, while carbon and nutrient concentrations in bamboo components decreased. Percentages of below-ground biomass and element stocks to total biomass and stocks decreased with the increase of stem density, whereas above-ground biomass and element stocks exhibited the opposite tendency. Moreover, more above-ground biomass and elements were allocated to higher part in the higher density population. In addition, percentages of culm biomass, above-ground biomass and element stocks below 100 cm culm height (H₁₀₀) increased with the increase of stem density, while percentages of branch and leaf biomass below H₁₀₀ decreased. Pearson’s correlation analyses revealed that root biomass, above-ground biomass, below-ground biomass and total biomass significantly correlated to leaf biomass in H_100?200 and total leaf biomass within high density population, while they significantly correlated to leaf biomass in H_50?150 within low density population. The results suggested that dwarf bamboo performed an efficient adaptive strategy to favor limited resources by altering biomass, carbon and nutrients distribution pattern in the dense population.     

Interactions between IL17A, IL23R, and STAT4 polymorphisms confer susceptibility to intestinal Behcet's disease in Korean population

AimsAlthough polymorphisms in IL23R have recently been proposed to predispose to Behcet's disease (BD), associations between IL23R polymorphisms and intestinal BD have yet to be elucidated. We therefore performed a study to evaluate whether IL17A, IL23R, and STAT4 polymorphisms are associated with susceptibility to intestinal BD in the Korean population.Main methodsSingle nucleotide polymorphisms (SNP) in the IL17A, IL23R, and STAT4 genes were analyzed using DNA sequencing, denaturing high performance liquid chromatography, and TaqMan genotyping assays.Key findingsIndividual polymorphism analysis revealed that the TT genotype of IL17A rs8193036 (odds ratio (OR) 2.10, 95% confidence interval (CI) (1.12–3.92), p = 0.021), and GG + GT genotype of IL23R rs1884444 (OR 1.92, 95% CI (1.03–3.57), p = 0.034) was associated with the development of intestinal BD. When these two genotypes were combined, the risk of BD increased compared to that of patients with no-risk or one-risk genotype (OR 2.21, 95% CI (1.13–4.34), p = 0.021). Furthermore, statistically significant gene–gene interactions were observed between G149R in IL23R vs. rs11685878 in STAT4, rs2275913 in IL17A vs. rs7574865 in STAT4, and rs11889341 in STAT4 vs. rs2275913 in IL17A. The haplotypes of IL17A had a positive association with intestinal BD risks, whereas those of IL23R were protective for disease development.SignificanceOur results indicate that the interaction of specific IL17A, IL23R, and STAT4 SNPs modulate susceptibility to intestinal BD in the Korean population, suggesting that the IL-17/23 axis plays a significant role in disease pathogenesis.     

Insulin-like growth factor axis gene polymorphisms modify risk of pancreatic cancer

Objective: Insulin-like growth factor (IGF)-axis genes plays a critical role in cancer development and progression via their impact on the RAS/MAPK/ERK and PI3 K/AKT/mTOR signaling pathways. We hypothesized that IGF-axis genetic variants modify individual susceptibility to pancreatic cancer. Methods: We retrospectively genotyped 41 single-nucleotide polymorphisms of 10 IGF-axis genes (IGF1, IGF2, IGF1R, IGF2R, IGFBP1, IGFBP3, IGFBP5, IRS1, IRS2, and IRS4) in 706 pancreatic cancer patients and 706 cancer-free controls using Sequenom and TaqMan technology. The association between genotype and pancreatic cancer risk was evaluated using multivariate logistic regression. A P value ≤.007 at a false discovery rate of 10% was set as the significance level. Results: We observed that the IGF1 *10212C>A and Ex4+2776G>A and IGF1R IVS2?70184A>G and IVS2+46329T>C variant genotypes were significantly associated with decreased pancreatic cancer risk (odds ratio [OR] range, 0.60–0.75) and that IGFBP1 Ex4+111A>G (I253M) was significantly associated with increased pancreatic cancer risk (OR = 1.46) after adjusted for other risk factors and multiple comparisons (P ≤ .007). IGF2R and IGFBP3 variant haplotypes were associated with increased and decreased pancreatic cancer risk, respectively (P < .001). We also observed a weak interaction of the IGF1R IVS2+46329T>C and IGF2R Ex45+11C>T (L2222L) genotypes with diabetes (P_interaction = .05) and interaction of IGF2R and IRS1 genotypes with alcohol consumption (P_interaction = .03 and .019, respectively) on increased pancreatic cancer risk. Conclusion: These findings support our hypothesis that polymorphic variants of IGF-axis genes act alone or jointly with other risk factors to affect susceptibility to pancreatic cancer.     

Genetic and environmental influences on oxidative damage assessed in elderly Danish twins

Previous studies have shown an association between oxidative stress and various diseases in humans including cancer, cardiovascular disease, diabetes, and chronic respiratory disease. To what extents this damage is determined by genetic and environmental factors is unknown. In a classical twin study with 198 elderly twins we examined the contributions of genetic versus environmental factors to nucleic acid oxidation and lipid peroxidation. Urinary excretion of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG), 8-oxo-7,8-dihydroguanosine (8-oxoGuo), and dinor,dihydro F₂-isoprostane metabolites (F₂-IsoP-M) was measured using liquid chromatography–tandem mass spectrometry. The environmental influence on nucleic acid oxidation and lipid peroxidation was predominant, leaving only little influence from genetic factors, as evidenced by no differences in intraclass correlations between monozygotic (MZ) and dizygotic (DZ) twins, neither for 8-oxodG (r_MZ = 0.55, r_DZ = 0.47; P = 0.43), F₂-IsoP-M (r_MZ = 0.33, r_DZ = 0.22; P = 0.42), nor 8-oxoGuo (r_MZ = 0.45, r_DZ = 0.58; P = 0.21). Accordingly, heritability estimates for the three markers of oxidative damage were low (h² = 0.17–0.22). The three urinary markers of oxidative stress were closely correlated (r = 0.60–0.84). In conclusion, we demonstrated in a large population of elderly Danish twins that “whole-body” oxidative damage to nucleic acids and lipids is predominantly determined by potentially modifiable nongenetic factors.     

A comparison of a deterministic and stochastic model for Hepatitis C with an isolation stage

We formulate a deterministic epidemic model for the spread of Hepatitis C containing an acute, chronic and isolation class and analyse the effects of the isolation class on the transmission dynamics of the disease. We calculate the basic reproduction number R₀ and show that for R₀≤1, the disease-free equilibrium is globally asymptotically stable. In addition, it is shown that for a special case when R₀>1, the endemic equilibrium is locally asymptotically stable. Furthermore, an analogous stochastic epidemic model for Hepatitis C is formulated using a continuous time Markov chain. Numerical simulations are used to estimate the mean, variance and probability distributions of the discrete random variables and these are compared to the steady-state solutions of the deterministic model. Finally, the expected time to disease extinction is estimated for the stochastic model and the impact of isolation on the time to extinction is explored.     

Effect of enhanced Renilla luciferase and fluorescent protein variants on the Förster distance of Bioluminescence resonance energy transfer (BRET)

Bioluminescence resonance energy transfer (BRET) is an important tool for monitoring macromolecular interactions and is useful as a transduction technique for biosensor development. Förster distance (R₀), the intermolecular separation characterized by 50% of the maximum possible energy transfer, is a critical BRET parameter. R₀ provides a means of linking measured changes in BRET ratio to a physical dimension scale and allows estimation of the range of distances that can be measured by any donor–acceptor pair. The sensitivity of BRET assays has recently been improved by introduction of new BRET components, RLuc2, RLuc8 and Venus with improved quantum yields, stability and brightness. We determined R₀ for BRET¹ systems incorporating novel RLuc variants RLuc2 or RLuc8, in combination with Venus, as 5.68 or 5.55 nm respectively. These values were approximately 25% higher than the R₀ of the original BRET¹ system. R₀ for BRET² systems combining green fluorescent proteins (GFP²) with RLuc2 or RLuc8 variants was 7.67 or 8.15 nm, i.e. only 2–9% greater than the original BRET² system despite being ～30-fold brighter.     

Characterization and early detection of grapevine (Vitis vinifera) stress responses to esca disease by in situ chlorophyll fluorescence and comparison with drought stress

Esca disease, as well as other trunk diseases of grapevine, is an important wood disease that impedes the water transport in plants by clogging the xylem vessels. This type of effect is not detectable for years, due to the long latency time of the disease. In a field experiment, the susceptibility of Vitis vinifera cv. Cabernet sauvignon and Merlot to esca disease was evaluated by visual assessment of foliar symptoms and by necrosis and white rot indexes. C. sauvignon was highly susceptible and Merlot was tolerant to esca. The characteristics of fast chlorophyll a fluorescence transient were investigated in attached leaves by using the so-called JIP-test. The fluorescence transient was analyzed and plants without visible esca foliar symptoms were compared with those showing symptoms. In C. sauvignon, alteration of the photosynthetic apparatus could be detected 2 months before the appearance of foliar symptoms in autumn. To our knowledge, this is the first report of early detection of esca disease using a nondestructive method. For Merlot, only one JIP-test parameter was affected. However, when both cultivars were compared, the relationship of the performance index (defined by the density of reaction centers (RCs) and by the yields φ_Po and ψ_o; PI_ABS = [RC/ABS][φ_Po/(1 − φ_Po)][ψ_o/(1 − ψ_o)]) versus the calculated rate of the electron transfer [probability that an absorbed photon moves an electron further than $Q_{\text{A}}^{-}$; φ_Eo = φ_Poψ_o = (TR_o/ABS)(ET_o/TR_o) = ET_o/ABS = (1 − F₀/F_M)(1 − V_J)] permitted us to separate the highest performing cultivar Merlot from the susceptible C. sauvignon. Also, the method used allowed us to detect modification of the photosystem II (PS II) performance in greenhouse-grown Riesling × Sylvaner after a drought stress. Finally, the comparison of the fluorescence transients of esca-affected and drought-stressed grapevines provided information on the differentiated functional-behavior patterns of PS II for the two stress types. These results suggest that esca infection cannot simply be interpreted as a water transport deficit through xylem dysfunction, but that other reaction mechanisms in the plants must be considered. The possibility to use fast chlorophyll a fluorescence monitoring as a wood decay early detection tool is discussed.     

Photosynthesis of lichens from lichen-dominated communities in the alpine/nival belt of the Alps – II: Laboratory and field measurements of CO2 exchange and water relations

CO₂ exchange and water relations of selected lichen species were investigated in the field and also in the laboratory, at a height of 3106 m above sea level in the Austrian Alps, during the short snowless summer period from middle of July to the end of August. In the course of the field investigations, clear summer days were quite rare. Altogether 14 diurnal courses of CO₂ exchange were measured spanning a time of 255 h of measurements.The air temperatures measured close to the ground ranged between −0.7 and 17.1 °C and their daily fluctuation was lower than 10.7 °C. Fog was present for more than one-third of the measuring period and relative humidity (RH) exceeded 90% in almost half of the time. Temperature optimum of net photosynthesis (NP) of Xanthoria elegans and Brodoa atrofusca determined in the laboratory increased with increasing photosynthetic photon flux density (PPFD) from 1.5 to 11.3 °C and the maximal CO₂ uptake was found to be at 10 °C. In the field the lichens were metabolically active at air temperatures between −0.7 and 12.8 °C. The light compensation points (LCP) of both lichen species ranged in the laboratory between 50 and 200 μmol m⁻² s⁻¹ PPFD (0–20 °C) and in the field between 22 and 56 μmol m⁻² s⁻¹ PPFD (3–8 °C). At 30 °C the NP of X. elegans surpassed the LCP, whereas B. atrofusca remained below the LCP. NP in X. elegans did not reach light saturation at 1500 μmol m⁻² s⁻¹ PPFD. NP in B. atrofusca reached light saturation at low temperatures (−5 to +5 °C). At higher temperatures light saturation was almost detectable. On sunny days the lichens in the field were metabolically active only for 3 h during the early morning. In this time they reached the maximal values or values close to their maximal CO₂ uptake in situ. Under dry weather conditions the lichens dried out to a minimal water content (WC) of 5–12% which is below the moisture compensation point (MCP) of 34–25%. The optimal WC was between 90% and 120% dry weight (DW) in B. atrofusca and Umbilicaria cylindrica, in X. elegans between 140% and 180% DW. Species specific differences in water-holding capacity, desiccation intensity and in the compensation points of temperature, light and moisture are responsible for differences in metabolic activity. The lichens were active during less than half of the observation time. Total time of NP of X. elegans was 24% of the measuring period, for U. cylindrica 22% and for B. atrofusca 16%.     

UVB-induced DNA damage, generation of reactive oxygen species, and inflammation are effectively attenuated by the flavonoid luteolin in vitro and in vivo

Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human keratinocytes resulting in skin inflammation, photoaging, and photocarcinogenesis. The flavonoid luteolin is one of the most potent antioxidative plant polyphenols. We investigated the UV protective and antioxidant properties of luteolin in human keratinocytes in vitro, ex vivo, and in vivo. Spectrophotometric measurements revealed extinction maxima of luteolin in the UVB and UVA range. UV transmission below 370 nm was < 10%. In human skin, luteolin effectively reduced the formation of UVB-induced cyclobutane pyrimidine dimers. The free radical scavenging activity of luteolin was assessed in various cell-free and cell-based assays. In the cell-free DPPH assay the half-maximal effective concentration (EC₅₀) of luteolin (12 μg/ml) was comparable to those of Trolox (25 μg/ml) and N-acetylcysteine (32 μg/ml). In contrast, in the H₂DCFDA assay performed with UVB-irradiated keratinocytes, luteolin (EC₅₀ 3 μg/ml) was much more effective compared to Trolox (EC₅₀ 12 μg/ml) and N-acetylcysteine (EC₅₀ 847 μg/ml). Luteolin also inhibited both UVB-induced skin erythema and the upregulation of cyclooxygenase-2 and prostaglandin E₂ production in human skin via interference with the MAPK pathway. These data suggest that luteolin may protect human skin from UVB-induced damage by a combination of UV-absorbing, DNA-protective, antioxidant, and anti-inflammatory properties.     

Influence of selected host plants on biology of castor whitefly,Trialeurodes ricini (Hemiptera: Aleyrodidae)

The development time, immature survivorship, immature size, tertiary sex ratio, pre-oviposition period, fecundity, and preferences of the castor whitefly, Trialeurodes ricini on four host plant species (castor, eggplant, cotton and green bean) were evaluated under laboratory conditions. Development time from egg to adult emergence was the longest on cotton (33.3 days), the shortest on green bean (25.4 days), and intermediate on eggplant (28.5 days) and castor (28.3 days). The survival rate was the highest on castor (92.5%), followed by those on green bean (80.2%) and eggplant (73.8%), and the lowest on cotton (42.6%). The sex ratio was the highest on cotton (♀:♂ = 2.45:1.00), the lowest on eggplant (♀:♂ = 0.75:1.00), and intermediate on castor and green bean (♀:♂ = 1.04:1.00). T. ricini immatures and adults were generally larger when reared on castor and eggplant than on other plants. The net reproduction rate (R₀) was 57.656 females per female per generation, the generation time (T) was 35.9 days, the intrinsic rate of increase (r_m) was 0.1128 eggs per female per day, the gross reproduction rate (GRR) was 108.04 eggs per female per generation, the finite rate of increase (λ) was 1.1194 females per female per day, and the doubling time (DT) was 6.1149 days. In both no-choice and two-choice tests, T. ricini adults preferred castor for feeding and oviposition.     

Stable isotope liquid chromatography-tandem mass spectrometry assay for fatty acid amide hydrolase activity

Fatty acid amide hydrolase (FAAH) is the main enzyme responsible for the hydrolysis of the endocannabinoid anandamide (arachidonoyl ethanolamide, AEA) to arachidonic acid (AA) and ethanolamine (EA). Published FAAH activity assays mostly employ radiolabeled anandamide or synthetic fluorogenic substrates. We report a stable isotope liquid chromatography–tandem mass spectrometry (LC–MS/MS) assay for specific, sensitive, and high-throughput capable FAAH activity measurements. The assay uses AEA labeled with deuterium on the EA moiety (d₄-AEA) as substrate and measures the specific reaction product tetradeutero-EA (d₄-EA) and the internal standard ¹³C₂-EA. Selected reaction monitoring of m/z 66 → m/z 48 (d₄-EA) and m/z 64 → m/z 46 (¹³C₂-EA) in the positive electrospray ionization mode after liquid chromatographic separation on a HILIC (hydrophilic interaction liquid chromatography) column is performed. The assay was developed and thoroughly validated using recombinant human FAAH (rhFAAH) and then was applied to human blood and dog liver samples. rhFAAH-catalyzed d₄-AEA hydrolysis obeyed Michaelis–Menten kinetics (K_M = 12.3 μM, V_max = 27.6 nmol/min mg). Oleoyl oxazolopyridine (oloxa) was a potent, partial noncompetitive inhibitor of rhFAAH (IC₅₀ = 24.3 nM). Substrate specificity of other fatty acid ethanolamides decreased with decreasing length, number of double bonds, and lipophilicity of the fatty acid skeleton. In human whole blood, we detected FAAH activity that was inhibited by oloxa.     

Effect of melatonin implants on the incidence and timing of puberty in female red deer (Cervus elaphus)

A study was conducted to test the hypotheses that exogenous melatonin treatment of 11–13 month-old red deer hinds: (1) advances the timing of first ovulation, (2) increases the proportion of individuals attaining puberty at ～16 months of age, and (3) reduces the live-weight threshold for attainment of first pregnancy. A total of 3901 rising-2-year-old (R₂) hinds within two herds (A and B) across two years either received single melatonin implants on two occasions in summer (n = 1399) or were untreated controls (n = 2502). Hinds were joined with stags from mid January to mid May, and were subjected to real-time rectal ultrasonography in early June to assess pregnancy status (proxy for puberty attainment) and foetal age for conception date assignment. Live-weights were recorded for each hind in January (12 months of age) as a proxy for weight at puberty. Melatonin treatment of hinds was associated with a significant advancement in mean conception dates in both herds in both years (P < 0.05), with a cohort difference in mean dates between treated and control hinds ranging from 9 to 17 days. Analysis of the temporal distribution of conception dates for each cohort revealed bi-modal or tri-modal patterns of conception indicative of conceptions to first or subsequent ovulations (oestrous cycles). Across all cohorts, melatonin treatment was associated with higher conception rates to first ovulation (P < 0.05) resulting in greater overall synchrony of conceptions. Regression analysis demonstrated a significant negative slope for conception date against live-weight (P < 0.001), but there was no evidence that this slope varied with treatment, herd or year (P > 0.05); for every 10 kg increase in live-weight conception date was advanced by an average of 1.3 days. In Herd A, melatonin treatment was associated with significantly higher pregnancy rates in both years (90.3% vs. 78.0% in Year 1 and 84.4% vs. 57.1% in Year 2; P < 0.05). The principle effect of melatonin treatment was to increase the pregnancy rate of hinds of low body-mass. In Year 1, at 60 kg live-weight a logit regression model indicated a pregnancy rate of 52% for untreated hinds and 83% for treated hinds. At 105 kg the rate for both cohorts was 90%. In Herd B, melatonin treatment was associated with higher conception rates in both years but these differences were not significant following correction for slight differences in mean live-weight (P > 0.05). The study has demonstrated that factors influencing puberty attainment in R₂ red deer hinds can vary between populations. In Herd A, in which body mass of hinds immediately prior to their first potential breeding season may have been the principle limiting factor, melatonin treatment appears to have instigated the pubertal process in hinds that would otherwise be of insufficient body mass.