Watersheds are Schramm-Loewner Evolution curves

We show that in the continuum limit watersheds dividing drainage basins are Schramm-Loewner Evolution (SLE) curves, being described by one single parameter $\kappa$. Several numerical evaluations are applied to ascertain this. All calculations are consistent with SLE$_\kappa$, with $\kappa=1.734\pm0.005$, being the only known physical example of an SLE with $\kappa<2$. This lies outside the well-known duality conjecture, bringing up new questions regarding the existence and reversibility of dual models. Furthermore it constitutes a strong indication for conformal invariance in random landscapes and suggests that watersheds likely correspond to a logarithmic Conformal Field Theory (CFT) with central charge $c\approx-7/2$.Comment: 5 pages and 4 figure

Monitoring of Cochlodinium sp for shrimp farms in Hormozgan Province

The Blooming due to the some species of phytoplanktons especially Dynoflagellates has made some problems for water ecosystems and aquaculture. In this study, the density of phytoplanktons specially Cochlodinium sp. and also environmental factors such as temperature, pH, dissolved Oxygen, and transparency were recorded two weekly in 18 stations of Hormozgan province, Iran in order to monitoring of the possibility of phytoplankton blooming. During six months monitoring, the target phytoplankton, Cochlodinium sp was not observed in shrimp farms. But, other phytoplanktons and zooplanktons were observed as follow: 13 genus of phytoplankton and six genuses of zooplanktons has found in ponds, main water channel and sea. The diatoms with 10 genuses had the highest abundance and Dynoflagellates with 3 genuses had the lowest abundance and blue-green phytoplankton with one genus was in lowest group. Totally, diatoms with 77%, Dynoflagellate with 15% and blue-green alga with 8% abundance were the main populations of planktons in the studied area

Effects of Leaf Mineral Compounds on Biology and Survival of Xanthogaleruca luteola Muller (Coleoptera: Chrysomelidae)

Introduction: Investigation the relationship between herbivores and their host plant has long been one of the critical areas of study in plant science research. Herbivores should find sufficient nutritional and mineral compounds to survive on the Earth. Elm leaf beetle is one of the most destructive pests among species of elm family. This insect feeds from elm plants during its larvae and youth life cycle causing crest distortion and many other physiological problems to the host plant. These problems in turn decrease host plant’s resistance to other pests and diseases. In this vein, effects of some minerals such as nitrogen, phosphorus and potassium, in four host plants including Ulmus carpinifolia, U. carpinifolia var. umbraculifera, Zelkowa carpinifolia and Celtis coucasica , on larval development and survival of elm leaf beetle, Xanthoga lerucaluteola (Coleoptera: Chrysomelidae), were studied under laboratory conditions (26±2ᵒC, 65±5% RH and 16:8 L: D). Material and Methods: Elm leaf beetle eggs were collected from the elm trees on the campus of faculty of natural resources at the university of Guilan, in north of Iran. Larvae were reared on different host plants in plastic jars and their biology and survival was determined. Some mineral compounds were assessed for the foliage of every host plants. Leaf nitrogen content was analyzed according to the technique introduced by Baker and Thompson. Phosphorus was measured based on Moore technique and potassium was determined by flame photometer based on Hanlon protocol. Results and Discussion: Analysis of variance showed that there was significant difference between the four studied host plants in terms of amount of phosphorous, potassium and nitrogen. The highest and the lowest amount of phosphorous and potassium was observed in U. carpinifolia and Ta leaves respectively (F=22.56; df=8, 3 for phosphorous test and F=22.36; df= 8, 3 for potassium analysis). As for nitrogen, the amount of nitrogen is significantly higher in Azad treatment compared to other three treatments (F=168.98; df= 8, 3). In terms of survival and total larvae developmental time, first instar larvae which had reared on U. carpinifolia leaves developed into other instars in a significantly shorter time span, compared to larvae reared on other three host plants. It should be noted that larvae fed from Ta leaves did not developed into third instar; so for the fourth instar developmental time analysis only larvae fed from three other host plants were included in the analysis. In terms of pupal developmental time, analysis showed that the shortest developmental time was found in larvae reared on U. carpinifolia leaves (6.78 days) and the longest developmental time was seen in larvae fed from Azad treatments (9.32 days). As for survival of larvae, the result exhibited that larvae reared on U. carpinifolia leaves had a higher survival rate compared to larvae fed from other three host plants. Total larval developmental time of X. luteola was significantly highest on C. coucasica in comparison with the other three host plants used in the study. All larval instars showed the highest survival on U. carpinifolia and the lowest survival was found on C. coucasica. The results indicated that the larvae, which had fed on host plants with higher level of mentioned mineral, had shorter duration of development. Conclusion: This research revealed that the mineral nutrition of host plants probably has significant effects on herbivore insects performance. It could be concluded that larvae developmental time and survival is highly dependent on the type of nutritional compounds which is probably due in turn to mineral compositions of the host plants. In other words, one can conclude that different kinds of minerals with different concentrations can probably be one of the main factors affecting developmental time and survival of larvae. It is suggested that more physical and chemical characteristics of elm tree be investigated and measured to achieve more precise result in the area of elm beetle larvae’s developmental time and survival

Effects of high-pressure treatment on shelf life and quality of fresh lactic curd cheese

High-pressure processing (HPP) was investigated for controlling spoilage and extending the shelf life of fresh lactic curd cheese. Fresh lactic curd cheeses manufactured from pasteurised bovine milk using Lactococcus starters and flavourings were vacuum packed and subjected to pressures at the levels of 300 and 600 MPa for 5 min, up to a temperature of 22°C, then stored at 4°C. The number of spoilage yeasts and moulds were enumerated immediately after treatment and at time intervals of three, five and eight weeks of storage. The growth of yeasts and moulds was effectively controlled for up to eight weeks in samples pressurised at 300 and 600 MPa. The firmness and adhesiveness of the samples, analysed with a TA-XT2 Texture Analyser, gradually increased during storage, but no significant differences (p&gt;0.01) in textural properties were detected between pressure-treated and untreated samples. An untrained taste panel (n=12) also found no significant differences (p&gt;0.01) in the sensory characteristics of the pressure-treated and untreated samples in a ranking test. Cheeses pressurised at 600 MPa developed TCA-soluble peptides at a significantly lower rate (p&lt;0.01) than the untreated controls during storage up to eight weeks. High-pressure treatment was an effective process to control yeasts and moulds spoilage and extend the shelf-life of fresh lactic curd cheese without adverse effects on the sensory and textural attributes of the products

Effects of high pressure treatment on glycolytic enzymes of Lactococcus lactis subsp lactis, Streptococcus thermophilus and Lactobacillus acidophilus

High pressure processing (HPP) reduces the glycolytic activity of lactic acid bacteria (LAB) and provides a means to control further production of acidic metabolites in fermented dairy products during storage. However, there is limited information on the effects of HPP on specific enzymes of dairy starter bacteria responsible for the metabolism of lactose. The aim of this study was to determine pressure-induced inactivation of glycolytic enzymes in Lactococcus lactis subsp. lactis C10, Streptococcus thermophilus TS1 and Lactobacillus acidophilus 2400. Cultures were grown for 16 h in M17 or MRS broth containing 5% (w/v) lactose at pH 6.5 (maintained by addition of 10 M NaOH). The cells were harvested by centrifugation, washed and resuspended in 100 mM phosphate buffer (pH 6.5) and pressure-treated at 300 and 600 MPa (= 22 ºC, 5 min). The ability of pressure-treated resting cells of Lactococcus, incubated with 5% (w/v) lactose at 30 ºC, to ferment lactose was evaluated by determining titratable acidity (TA) during incubation. The activities of phospho-ß-galactosidase (P-ß-gal), ß-galactosidase (ß-gal) and lactate dehydrogenase (LDH) were determined in cell-free extracts of untreated and pressure-treated cells. Resting cells of Lactococcus treated at 600 MPa had a substantially lower rate of acidification than the controls and those treated at 300 MPa. Both P-ß-gal and ß-gal were significantly inactivated (p &lt; 0.01) in the starter cultures treated at 300 or 600 MPa. The LDH in Lactococcus and Lactobacillus was highly resistant to pressure treatment at 300 MPa. In contrast, the LDH in Streptococcus was almost completely inactivated at = 300 MPa. Industrial relevance: Continuing production of acidic metabolites in fermented dairy products during storage can be a technological challenge that adversely affects product quality. The current study demonstrates that high pressure processing (HPP) offers the potential of controlling this problem by inactivation of glycolytic enzymes in various mesophilic and thermophilic starter cultures. The findings of this research will assist in establishing optimised operating parameters for HPP treatment of cultured products to extend shelf-life, by reducing acid production during storage

Effects of various host plants on nutritional indices and some biochemical compounds in green oak leaf roller, Tortrix viridana L. (Lepidoptera: Tortricidae)

The green oak leaf roller, <em>Tortrix viridana</em> L., is one of the most destructive pests, causing damages to various species of oak, feeding on different host plants including <em>Quercus infectoria</em> Oliv, <em>Q. branti</em> Lindl, and <em>Q. libani</em> Oliv. Nutritional indices, activity of enzymatic and non-enzymatic compounds of <em>T. viridana</em> were studied under laboratory conditions. In addition, chemical components were analysed in the leaves of the three host plants. Fourth instar larvae reared on <em>Q. branti </em>showed the highest values of relative consumption rate (RCR), approximate digestibility, and consumption index (48.73±6.22; 90.45±1.06 and 97.45±12.44 respectively), while the lowest values were observed on <em>Q. libani</em>. Efficiency of conversion of ingested food in the fourth instar larvae was the highest (3.17±0.661) on <em>Q. libani</em> and the lowest (1.53±0.164) on <em>Q. branti</em>. The fifth instar larvae fed on <em>Q. libani</em> had the highest RCR (15.64±2.51). The highest amounts of triglycerides, uric acid, glucose, protein and the lowest activity of alkaline phosphatase were observed in the fifth instar larvae reared on <em>Q. libani</em>. The leaves of Q. libani highlighted the highest amounts of total nitrogen, total protein, water, potassium, magnesium and total carbohydrate. The present research suggested that the nutritional quality of the host plants have crucial effects on <em>T. viridana</em> larvae

Effects of temperature, light and incubation period on production, germination and bioactivity of Trichoderma atroviride

Aims: The goal was to determine the effect of temperature, light and incubation period on production, germination and bioactivity of Trichoderma atroviride LU132 against Rhizoctonia solani. Methods and Results: The incubation temperatures of 20, 25 or 30°C were assessed on the production of T. atroviride conidia under constant light over a 25 and 50 days periods. The resulting conidia were also studied for germination and bioactivity. Conidium production was maximum at 25°C after 20 days. The second peak of conidium production occurred at 45-50 days. Incubation at 25°C after 15 days showed optimum production of T. atroviride LU132. Conidia produced at 30°C gave the greatest germination and bioactivity in comparison with incubation at 20 or 25°C. Conclusion: This study indicates that the temperature at which conidia of T. atroviride are produced affects germination and bioactivity. Formulations based on production of the high conidia yield may not result in optimal bioactivity and there is a trade-off between quantity and quality of T. atroviride LU132 conidia. Conidium production was shown to be a continuous process, and increased under a dark/light regime. This is the first report of bimodal conidium production in a Trichoderma biological control agent (BCA), which is likely to be on 20 days cycle, and is dependent on colony age rather than abiotic factors. Conidia produced after 15 days are likely to be the most suitable for use in commercial production of this strain as a BCA. Significance and Impact of the Study: Most studies on Trichoderma-based BCA have only shown the effect of culture conditions on the high conidia yield regardless of conidium quality. This study is the first report on conidium quality affected by principal culture conditions for Trichoderma biological control formulations

Culturing conditions affect biological control activity of Trichoderma atroviride against Rhizoctonia solani in ryegrass

Aims: Effects of culture conditions on productivity, germinability and bioactivity of Trichoderma atroviride LU132 conidia were assessed to identify the factors affecting conidium ‘fitness’ (quantity and quality) and to withstand variable environmental conditions, increase conidial productivity, and perform optimum bioactivity. Methods and Results: The interaction effects of temperatures (20 or 30°C) vs hydrocarbon types (dextrose or sucrose in constant C : N 5 : 1) were assessed for bioactivity and colonization potential in pot experiments with ryegrass in the presence of pathogen, Rhizoctonia solani. Trichoderma atroviride produced in different culture conditions increased some growth parameters of ryegrass plant and also reduced the pathogenicity effects of R. solani. For example, Trichoderma colony produced at 20°C with sucrose increased all plant growth parameters and conidia produced at 20°C with dextrose gave the greatest bioactivity. Conclusion: The bimodal population cycle in T. atroviride recurred in pot experiments in a manner similar to that previously observed in agar plates but indicating that simulated natural conditions shortened the Trichoderma life cycle. Trichoderma colonized ryegrass root system and symbiotically interacted with ryegrass and greater ryegrass colonization resulted from medium production treatment with dextrose rather than sucrose. Significance and Impact of the Study: This study is the first report on the effects of inoculum production conditions on conidium quality of Trichoderma to colonize and to maintain populations in host rhizospheres, and also the ability to promote plant growth and suppress a soil-borne disease. The results of these experiments provide new knowledge on how manipulation of culture conditions of T. atroviride LU132 can influence conidium fitness, as a basis for optimizing commercial production of the fungus as a biological control agent