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This article presents studies on the effect of Sr and TiB on the crystallization process, mechanical properties, hardness, and density index of the Al-Si alloy from the EN AC-46000 group, with a narrowed chemical composition, produced by die-casting and HPDC (high-pressure die casting) technology. The research used the Box–Wilson method to design the experiment and stepwise multiple regression. To identify the optimal amount of Sr and Ti in the analyzed alloy that would simultaneously guarantee the maximization of UTS, YS, Agt, and HBW and the minimization of the DI (density index), multi-criteria optimization was performed. The modifiers were added to the liquid alloy as AlSr10 and AlTi5B1 master alloys. It was found that for 0.02–0.04 wt.% Sr and 0.05–0.08 wt.% Ti in the die castings, the highest mechanical properties, such as UTS, YS, Agt, and HBW (treated as stimulants in the experiment), can be obtained simultaneously with the lowest alloy gasification identified by DI (treated as a destimulant in the experiment). It was also confirmed that the same amount of the above-mentioned elements in HPDC castings caused an increase in UTS by approx. 14%, YS by approx. 6%, A by approx. 47%, and HBW by approx. 13%, with a relatively small increase in DI by approx. 5% compared to the unmodified alloy. [ABSTRACT FROM AUTHOR]

Introduction Rivers are known as the main sources of surface water in the world, which experience seasonal fluctuations in water level. These resources have severe damage to human societies and nature in flood conditions and have irreparable consequences in the drought seasons. Optimal utilization of these resources with maintaining the environmental conditions of the waterway and minimizing flood damage is considered one of the river engineering goals. Since the conventional methods of river management are imposed serious environmental threats on waterways and wetlands, consideration to these water resources requires attention to issues related to plant ecosystems, solving challenges of coastal bed erosion and predict the condition and management of the river in the future (Callow, 2012; Dawson and Haslam, 1983; Fan et al., 2013; Rose et al., 2010; Rowinski et al., 2018). One of the strategies that cause loss of flow energy in the river improves the hydrological system and river ecosystem is the presence of vegetation in the river banks and floodplains. Native vegetation in floodplains and coastal forests plays an important role in conserving waterway ecosystems, flood management, coastal protection in urban lands and agriculture adjacent to the river (Fathi-Moghadam, 1996). Vegetation will also control the width of the river and increase the stability of the shores by absorbing and settling suspended sediments in river banks. The plant species along rivers and waterways are composed of various vegetative components, mainly affected by the environmental conditions of their habitat, including the distance from the waterway bed, hydrological characteristics of the river, climatic and soil conditions. Obviously, the effect of each plant species in the ecosystem cycle varies and for each section of the river, a specific combination of plants will create optimal conditions. Methodology In this paper, effective parameters have been identified to investigate the effect of vegetation properties on drag force and the final functional relationship between dimensionless parameters for estimation of resistance to flow and drag coefficient in vegetated rivers will be: CD = f [yn/H, DI, ρV²yn4/EI] (1) Where CD is the drag coefficient, yn/H is the relative depth, DI is the vegetation density index and last parameter is the dimensionless number of the ratio of the flow velocity to the bending stiffness, which is used to investigate the effect of the vegetation flexibility. The experiments were conducted in an 8.30×0.80×0.55m flume with Plexiglas sidewalls and metal structure located in the Water and Environmental Engineering Faculty at Shahid Chamran University of Ahvaz, Ahvaz, Iran. The knife-edge part of the flume, which can move freely in a limited range, was used to measure the exerted force to the moveable part of the flume (which supports the vegetated model) by means of a dynamic load cell installed between the movable and fixed parts of the flume. the artificial vegetation models used in this study were similar to the natural sample of trees. Galvanized and polyethylene sheets have been used to make rigid and flexible artificial specimens with the same geometric shape and form to allow more accurate comparisons. Results and Discussion In this section, with the aim of practical use of the results, the independent variables are defined as dimensionless numbers based on the drag coefficient. Investigating the effect of the vegetation density index, the results showed that in both rigid and flexible models, increase of the vegetation density index leads to a decrease in the drag coefficient. By increasing the vegetation density index in the flexible model at yn/H = 1, the drag coefficient decreased by 19.8%, which is the highest rate of decrease in the drag coefficient. Also, the lowest rate for reduction of the drag coefficient with increase of the vegetation density index occurred in the rigid model and at yn/H = 0.6, which is equivalent to 10.3%. In fact, in the case of the maximum decrease in the drag coefficient, for an 80% increase in the vegetation density index, the drag force increased by 43.8%, and in the case of the minimum decrease in the drag coefficient, the drag force increased by 66.5%. By comparing the effect of flexibility of vegetation in rigid and flexible models, the results showed that in both cases, the drag coefficient decreases with increasing in velocity. In the flexible models, the slope of the drag coefficient curve has a decreasing trend faster than the rigid case. For the effect of the relative depth of the flow, the results showed that the drag coefficient in both models decreases with the increase in the relative depth, so that in the rigid and flexible models, with the increase in the relative depth from 0.6 to 0.8 and from 0.8 to 1, the drag coefficient decreases by 12.81% and 10.43%, respectively. Correlating the results, following relationships were obtained for the estimation of the drag coefficient for the rigid and flexible models, respectively: CD = 3.26 [yn/H]0.13 - 2.65(DI)-0.12 + 0.28[ρV²yn4/EI]-0.29 R² = 0.87 (2) CD = [yn/H]1.2 + (DI)0.16 - 0.32[ρV²yn4/EI]0.21 R² = 0.89 (3) Conclusions In the present study, the drag force absorption rate and the resistance coefficient were investigated and equations were correlated to estimate the drag coefficient. All experiments were performed in steady, uniform and turbulent flow. Rigid and flexible models were tested by different hydraulic parameters according to the flow conditions. A new index is produced to account for the effect of vegetation density on the drag coefficient. Investigating the effect of the vegetation density index showed that the increase in this index has a significant effect on reducing the drag coefficient, so that at the maximum increase of the density index, a decrease of 19.8% in the drag coefficient was measured. The results showed an increase in drag force absorption as a result of increase in vegetation density index and relative depth. In general, the increase in vegetation density index ranges 0.4 < DI ≤ 0.8, 0.8 < DI ≤ 1.1, 1.1 < DI ≤ 2.2 and 2.2 < DI ≤ 3.8 in comparison to the range of 0.2 ≤ DI ≤ 0.4; the drag force absorbed increases by 1.63, 2.46, 4.12 and 6.33 times, respectively. Also, increase of the relative depth from 0.6 to 0.8 and 1, the drag force increased by 49.7% and 46.9%, respectively. The index introduced in this study can be a reference index for monitoring the types of vegetation in floodplains and aquatic plants. The results of this study can be used in the numerical modeling for estimation water level during flood events and river engineering management. [ABSTRACT FROM AUTHOR]

The present study analyzes laboratory experiments on how shearing rate affects the shear strength and crushability of natural coarse sand, employing artificial neural network (ANN) analysis. This study tested three different coarse sands obtained from the crushing of natural rocks: Black Virgin Tuff, weathered Zeolitic Tuff, and calcareous limestone. The behavior of crushed sand specimens with consistent grading, which passed through sieve #4 and were retained on sieve #8, was analyzed using a direct shear box. The specimens were subjected to varied normal loads and shearing speeds to examine their behavior at different relative densities. The test results were analyzed using ANN to investigate the significance of shearing rates on shearing strength parameters, specifically internal mobilized peak friction, the constant volume (residual) internal friction angle, and the consequence of shearing rate on the particle's breakage index. The selected normal (Gaussian) rate significantly affected both the shear strength parameters and breakage. The loading rate increased both shear strength parameters and particle breakage. Therefore, it's highly recommended to maintain secure sets of shear strength values and comprehensive test data for assessing parameters at typical strain rates, prioritizing using slower rates whenever possible. [ABSTRACT FROM AUTHOR]

There was a good mix of young trees in open areas and mature trees in even-aged stands of Pinus brutia Ten. These trees in the stand formed based on the crown area of trees that grew under the same conditions. Increasing the distance between trees reduces competition and encourages development, just as it does in open areas. Therefore, 36 samples of varying densities were selected at random from this stand. All trees in one sample were measured to be a total of (30 × 30) m in height, crown width, and dbh. In addition, a data field was created for each stand density and the diameter, height and crown width of 34 trees growing at random in open areas were recorded. In this research, the tree density equation for Pinus brutia Ten. was established. We compared our density-weighted method to the Stand Density Index S.D.I. and determined the link between crown width and diameter for open regions. Finally, the paper showed that this technique may be used to calculate tree competition and by extension, the mitigation times necessary to achieve administrative goals in a stand. [ABSTRACT FROM AUTHOR]

The modification of silicon particles in as-cast aluminum alloys can be done with different modifiers. Sodium is the strongest one not so often used in aluminum casting plants. This is because sodium fading is considerably vigorous compared to other modifiers. This study examined the effect of sodium fading on the modification level of silicon particles in the AlSi7Cu0.5Mg (356) aluminum alloy. The cooling curve analysis has been applied to quantify sodium fading. Approximately 65 ppm of sodium in the tablet form was added to the melt. The sodium was held for 200 minutes in the melt to observe its fading. It was found that sodium does not fade rapidly, as the literature data proposed. Furthermore, it was recognized that modification with sodium produces more dross that can have a negative impact on the quality of cast parts if it is not properly removed from the melt. Besides thermal and chemical analysis, an image analysis technique can be additionally used as a quality control tool to assess the efficiency of modifiers. [ABSTRACT FROM AUTHOR]

The present work aims to propose a new analytical model intended to predict the water retention curves for granular materials based on data from tensiometric tests. Different analytical models have been used for the evaluation of soil water retention curves so far. It should be noted that the proposed model considers only one criterion in the selection of soils. This criterion is the physical property of particle distribution curve that can be used to determine the values of D50 and CU. In this study, the pore-access size distribution is investigated considering the effect of the coefficient of uniformity of sandy soils that were prepared with different density indexes (0.5, 0.7, and 0.9). Moreover, the proposed model equation is based on the physical properties of soil. This equation made it possible to describe the water retention curve and to estimate the pore-access size distribution without performing any experimental tests. The findings allowed asserting that the uniformity of the particle size curves corresponds to a good uniformity of the pore-access size distribution. In addition, it was revealed that the suction increased as the density index went up, which matches well with the experimental data. Moreover, it may clearly be noted that the distinctive retention properties of unsaturated soils can be observed on the abovementioned curves. Further, it was found that the ratio of the grain size over the pore-access size increased as the uniformity coefficient augmented.

IntroductionIntegrated water management (IWM) involves a range of policies, actions, and organizational processes that go beyond traditional hydrology to consider multifaceted aspects of complex water resource systems. Due to its transdisciplinary nature, IWM comprises input from diverse stakeholders, each with unique perceptions, values, and experiences. However, stakeholders from differing backgrounds may disagree on best practices and collective paths forward. As such, successful IWM must address key governance principles (e.g., information flow, collective decision-making, and power relations) across social and institutional scales. Here, we sought to demonstrate how network structure impacts shared decision-making within IWM.MethodsWe explored a case study in Houston, Texas, USA, where decision-making stakeholders from various sectors and levels of governance engaged in a participatory modeling workshop to improve adoption of nature-based solutions (NBS) through IWM. The stakeholders used fuzzy cognitive mapping (FCM) to define an IWM model comprising multifaceted elements and their interrelationships, which influenced the adoption of NBS in Houston. We applied grounded theory and inductive reasoning to categorize tacit belief schemas regarding how stakeholders viewed themselves within the management system. We then used FCM-based modeling to explore how unique NBS policies would translate into more (or less) NBS adoption. Finally, we calculated specific network metrics (e.g., density, hierarchy, and centrality indices) to better understand the structure of human-water relations embedded within the IWM model. We compared the tacit assumptions about stakeholder roles in IWM against the quantitative degrees of influence and collectivism embedded within the stakeholder-defined model.Results and discussionOur findings revealed a mismatch between stakeholders' external belief statements about IWM and their internal assumptions through cognitive mapping and participatory modeling. The case study network was characterized by a limited degree of internal coordination (low density index), high democratic potential (low hierarchy index), and high-efficiency management opportunities (high centrality index), which transcended across socio-institutional scales. These findings contrasted with several of the belief schemas described by stakeholders during the group workshop. We describe how ongoing partnership with the stakeholders resulted in an opportunity for adaptive learning, where the NBS planning paradigm began to shift toward trans-scale collaboration aimed at high-leverage management opportunities. We emphasize how network analytics allowed us to better understand the extent to which key governance principles drove the behavior of the IWM model, which we leveraged to form deeper stakeholder partnerships by identifying hidden opportunities for governance transformation.

In this study, the effect and mechanism of ultrasonic melt treatment (UST) were studied to achieve high-quality molten Al–Mg alloy. The purpose was to analyze the change in the cleanliness of molten aluminum according to UST process conditions such as ultrasonic power, treatment duration, and stabilization duration for molten Al–Mg alloy, and to find the optimal ultrasonic process conditions to achieve high-quality molten aluminum. UST results were compared to the effect of the Gas Bubbling Filtration (GBF) process, which is a general molten aluminum treatment process. Density index, bifilm index, porosity, and X-ray CT analysis were used for quality evaluation of melt cleanliness. UST was performed at a frequency of 19.7 kHz and two outputs of 600 W and 1200 W after maintaining 1 kg of molten aluminum at 800 °C for 10 min. The UST treatment durations were 1, 3, and 5 min, the stabilization durations after treatment were 0, 10, and 20 min. Then the quality of the molten aluminum was measured. The GBF treatment was applied for 1, 5, 10, or 30 min under impeller rotation speed of 300 rpm and gas flow rate of 1 L/min. During UST, the melt quality improved as the ultrasonic power increased and the treatment duration increased. To secure the high melt quality, UST could obtain the required degassing effect after 3 min of treatment, whereas GBF treatment took 10 min. The bubble size generated by UST is smaller than that by GBF, so UST has higher mas transfer coefficient of hydrogen than GBF and hydrogen in the melt could be removed with only a short UST treatment. UST was superior to GBF immediately after treatment, however, the melt quality deteriorated during the stabilization after UST. It caused from the unstable oxide film and a relatively rapid high-temperature oxidation, so appropriate molten metal management and rapid post-processing are necessary after UST treatment.

By studying the host-selection patterns of oxpecker species, researchers can gain valuable insights into their ecological roles and interactions with different host species. This information is crucial for developing effective conservation strategies that prioritise the protection of oxpeckers and their host populations. The study conducted field observations and recorded data on the number of oxpeckers and their respective host species. Additionally, this study investigated the relationship between host species and host parameters (body mass and hair length) in the Salambala conservancy in northeastern Namibia. Selection and density indices were used to calculate the number of host animals supporting one oxpecker as well as the oxpecker density on a host's body surface. Pentad-based counts of oxpeckers and ungulates were conducted. Of the observed oxpeckers, 75% were Red-billed and 25% Yellow-billed Oxpeckers. These findings suggest that Red-billed Oxpeckers (Buphagus erythrorhynchus) are more commonly found on host species than Yellow-billed Oxpeckers (Buphagus africanus). The selection index indicates that Red-billed Oxpeckers have a higher preference for impala (Aepyceros melampus) compared to cattle (Bos taurus), while Yellow-billed Oxpeckers show a lower preference for goats (Capra aegagrus hircus) compared to cattle. The selection indices for impala and cattle for both oxpecker species were highest during the wet season. In terms of correlation analysis, there were no significant correlations between selection and density indices and host hair length or speciestypical body mass. [ABSTRACT FROM AUTHOR]

Fruit sugars are gaining attention for their nutraceutical benefits. High sugar in ripe and over-ripe bananas makes them difficult for convective drying. In this study, red banana (RB) pulp was added with different gum derivatives as foaming agent (FA) (4 % w/w) viz., acacia gum(GA), carrageenan (CG) and gelatine(GE). Maltodextrin and carboxymethyl-cellulose were added as foam-stabilizers (FS). FA addition resulted in low density foam (RBGE-50 % reduction) with improved foam stability (RBGA-94.42 %). Powders were low in hygroscopicity (RBGA-18.62 g 100 g −1) with optimum flowability. The particle size (54.95 to 69.86 μm) of RB powder increased with gum derivatives addition. Secondary metabolites varied significantly in powder samples. Positive correlation of secondary metabolites with DPPH assay was observed. RBGA showed higher prebiotic activity (0.68) and supported the growth of tested Lactobacillus strain. Therefore, foam-mat dried RB powder with GA could be used in food formulation as low-cost alternative fruit sugar with higher nutritional, functional and prebiotic properties. [Display omitted] • Foam stabilizers alone will not have positive outcome on red banana powder. • Foaming agents and stabilizers in banana pulp reduced the hygroscopicity of powder. • Foam mat drying enhanced nutrients and bioactive compounds retention in red banana. • Non-enzymatic browning was reduced with addition of -gum derivatives • Acacia gum addition enhanced prebiotic activity on red banana powder. [ABSTRACT FROM AUTHOR]

In this study, we performed undrained cyclic–torsional–shear tests on clean and silty sands to examine post-liquefaction volumetric strain. Accordingly, we proposed a novel density index—ultimate volumetric strain—to evaluate the density of clean sand and silty soils; the proposed density index is based on soil compressibility. We discussed the test results with respect to relative density, skeleton void ratio, and ultimate volumetric strain. Consequently, we confirmed that ultimate volumetric strain showed good correlation with post-liquefaction volumetric strain irrespective of soil type, whereas values for relative density and skeleton void ratio were discordant. Further, we observed that, compared to maximum shear strain, accumulated shear strain was a better index for representing the effect of loading history. From these results therefore, we proposed a chart to evaluate post-liquefaction volumetric strain based on ultimate volumetric strain and accumulated shear strain.

The present study reports ten identified species of zooplankton in an Algerian lake. Seven stations were chosen according to different criteria and eleven physicochemical parameters were estimated to describe the water quality of each station. Qualitative and quantitative samples were collected from the lower horizon to the surface monthly, in October 2006 and from January to March 2007. In January, the highest species richness (S=9) was recorded in the upper lake corresponding to greater diversity (H’=1.41). The maximum density (28101 ind./L) was observed at the most vegetated site. The crustacean community consisted of 5 Cladocerans, 2 Cyclopidae and 1 Calanoida, however, rotifers were scarce. The CCA analysis reveals that most cladocerans seem to be associated with water hardness contrary to rotifers and copepods. The zooplankton structure was dominated in the north by copepods. However, cladocerans showed an inverse pattern from north to south. Taken together, our data indicate that community structure changes over time during our sampling surveys and in the lake, three zooplanktocenoses were identified. Therefore, it seems that environmental factors linked to the Mediterranean climate play a fundamental role in shaping the architecture of the food webs and the distribution of zooplanktocenoses of the Hamiz reservoir. [ABSTRACT FROM AUTHOR]

In this study, we performed undrained cyclic–torsional–shear tests on clean and silty sands to examine post-liquefaction volumetric strain. Accordingly, we proposed a novel density index—ultimate volumetric strain—to evaluate the density of clean sand and silty soils; the proposed density index is based on soil compressibility. We discussed the test results with respect to relative density, skeleton void ratio, and ultimate volumetric strain. Consequently, we confirmed that ultimate volumetric strain showed good correlation with post-liquefaction volumetric strain irrespective of soil type, whereas values for relative density and skeleton void ratio were discordant. Further, we observed that, compared to maximum shear strain, accumulated shear strain was a better index for representing the effect of loading history. From these results therefore, we proposed a chart to evaluate post-liquefaction volumetric strain based on ultimate volumetric strain and accumulated shear strain. [ABSTRACT FROM AUTHOR]

This paper examines the importance of empirical formulas for estimating the hydraulic conductivity of non--cohesive soils, taking into account their compaction. Empirical formulas are often used in practice to quickly and cost-effectively determine hydraulic conductivity of soil. Verification of calculation of this parameter was performed for five formulas taking into account the characteristic diameters of grains and porosity. The results obtained by calculations were compared with the results of laboratory tests performed on soil samples with the same porosity coefficients (at different density index) as assumed in the calculation method. An empirical formula has been proposed to correct the hydraulic conductivity of soils obtained from the Hazen formula by taking into account the density index of a given soil. [ABSTRACT FROM AUTHOR]

The objective of the research was to evaluate the densification of eight Mexican woods: Cupressus lindleyi Klotzsch ex Endl., Cedrela odorata L., Swietenia macrophylla King, Tabebuia donnell-smithii Rose, Fraxinus uhdei (Wenz.) Lingelsh, Fagus mexicana Martínez, Dalbergia palo-escrito Rzed. & Guridi-Gómez, and Guazuma ulmifolia Lam. The wood was densified with a thermo-mechanical process. Before and after densification, the density, the ultrasonic wave speed in the longitudinal direction and the dynamic module were determined experimentally. In addition, the densified, elastic and treatment quality indices were calculated. Between the non-densified wood and the densified wood, in the eight species, statistically significant differences were found for density, wave velocity and dynamic modulus. The densified, elastic and quality indices are similar to the same parameters of the species reported in the literature. These indicators suggest that it is possible to increase the density of these species and thus expand their uses. [ABSTRACT FROM AUTHOR]

The use of secondary aluminium is increasingly being promoted in the automotive industry for environmental reasons. The purpose of this study was to demonstrate that it is possible to obtain a recycled AlSi10MnMg(Fe) aluminium alloy with equal metallurgical quality to that of a primary AlSi10MnMg alloy when an adequate melt treatment is applied. The melt treatment consisted of deoxidation, degassing and skimming in accordance with the detailed procedure described in this article. The metallurgical qualities of one primary and two secondary alloys were assessed using thermal analysis, the density index test, the macroinclusion test and the microinclusion level test before and after melt treatment. The thermal analysis allowed us to compare the variables of the solidification cooling curve (Al primary temperature and its undercooling; Al-Si eutectic temperature and its predictive modification rate). The density index test was used to evaluate the hydrogen gas content in the melt. The macroinclusion test was used to evaluate the melt cleanliness, while the microinclusion level test was used to perform the inclusion identification and quantification analyses. This study showed the feasibility of manufacturing structural components using 100% recycled secondary aluminium alloy through V-HPDC technology.

In this study, the optimal conditions of gas bubbling filtration (GBF) treatment for securing highly-clean molten Al-Si-Mg-Cu alloy were identified. The effects of GBF treatment time and stabilization time on the degree of molten metal cleanliness were examined by measuring melt quality parameters such as density index, bifilm index, porosity, and the amount of dissolved hydrogen [H]. A high melt quality was achieved when GBF treatment was performed on 10 kg melt for more than 10 min (i.e., 1 L gas/kg melt). However, as the stabilization holding time after GBF treatment increased to 10, 20, and 30 min, the melt quality degraded. GBF treatment for 30 min had a similar effect to treatment for 10 min, and the degree of deterioration of melt quality during the stabilization time was also similar. Considering the economics, 10 min GBF treatment and short holding time are required. Observations of the shape and volume of the largest pore suggested the cause of defect formation and confirmed that the volume of the largest pore can be used as an index of the melt quality.

The present study investigated the effect of the casting conditions for the reduced pressure test (RPT) on the melt quality of Al-Si alloy. The casting conditions considered in RPT were the atmospheric exposure during melting, sampling method, and mold pre-heating temperature. Density Index (DI) was measured to quantify the melt quality of the Al-Si alloy casted with the different casting conditions for the RPT. The sample with blocking atmospheric exposure during melting was 5.6% lower in DI than the one without blocking. DI showed a 1.9% gap between scooping-out and pouring sampling methods. Increasing mold pre-heating temperature from 100 °C to 250 °C increased the DI of the alloy from 8.5% to 18.7%. On the other hand, when the mold pre-heating temperature was 350 °C, the DI of the alloy dropped sharply to 0.9%. The melt quality of the alloys was analyzed by measuring the pores and microstructure and simulating the solidification of the samples. It was presumed that the oxides and inclusions in the molten alloys caused the difference in DI according to the atmospheric exposure and the sampling method. The difference in DI according to the mold pre-heating temperature could be understood by calculating the solidification starting time and hydrogen diffusion coefficient during the solidification of the alloys in RPT.

Weaver ants are used for biological control of insect pests in plantation crops. To obtain proper pest control, ant densities need to be high. Food availability and nesting facilities on host plants and management practices may affect ant performance. In the present study, we tested the effect of two host plant species (mango and cashew) and three different management practices (ants only, ants fed with sugar and ants combined with the soft chemical insecticide Spinosad) on weaver ant performance. Performance was assessed over a 22 month period, as an index value based on the number of ant trails per tree and as the number of ant nests per tree. A total of 216 trees (72 per treatment) were observed in each crop. In all treatments, the ants performed better in mango compared to cashew. Using the index based performance measure, ants also performed better in the sugar treatment as compared to the two other treatments, whereas this was not the case in cashew. We conclude that sugar feeding can be used to increase ant populations in mango. We also found that the treatment with Spinosad in combination with ants showed performance equal to the treatments with only ants, suggesting that Spinosad did not negatively affect ant populations. We therefore conclude that Spinosad is compatible with the use of weaver ants in integrated pest management programs.

Modern excavation techniques aim accurately to recover extant archaeological data. Usually bone micro-fragments are gathered as a result, however, during archaeological analysis these remains are often set apart as indeterminate bones and generally do not contribute to the interpretation of the deposits. How to decipher archaeological palimpsests using these small bone fragments is the aim of this paper. El Mirón Cave, located in northern Iberia, contains a very rich Cantabrian Lower Magdalenian deposit (17-15 uncal ka BP) with high densities of faunal remains and artefacts. Here, we present zooarchaeological, taphonomic and spatial distribution analyses of macromammal finds, including those small bone fragments, accumulated during a series of intensive and repeated human occupations found in the outer vestibule excavation area. Our results show that a broad spectrum of activities was performed there, including meat, marrow and grease processing and waste abandonment. We propose that bone micro-fragments must be considered when addressing human subsistence reconstructions from animal remains, as they represent the leftovers of the chaîne opératoire of animal carcass exploitation. The archaeological implications of their inclusion are extremely valuable, especially when deciphering palimpsests. A multidisciplinary approach to study these small animal remains provides information that otherwise would be missed. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Populations of wild boar and feral pigs are increasing worldwide, in parallel with their significant environmental and economic impact. Reliable methods of monitoring trends and estimating abundance are needed to measure the effects of interventions on population size. The main aims of this study, carried out in five English woodlands were: (i) to compare wild boar abundance indices obtained from camera trap surveys and from activity signs; and (ii) to assess the precision of density estimates in relation to different densities of camera traps. For each woodland, we calculated a passive activity index (PAI) based on camera trap surveys, rooting activity and wild boar trails on transects, and estimated absolute densities based on camera trap surveys. RESULTS: PAIs obtained using different methods showed similar patterns. We found significant between‐year differences in abundance of wild boar using PAIs based on camera trap surveys and on trails on transects, but not on signs of rooting on transects. The density of wild boar from camera trap surveys varied between 0.7 and 7 animals/km2. Increasing the density of camera traps above nine per km2 did not increase the precision of the estimate of wild boar density. CONCLUSION: PAIs based on number of wild boar trails and on camera trap data appear to be more sensitive to changes in population size than PAIs based on signs of rooting. For wild boar densities similar to those recorded in this study, nine camera traps per km2 are sufficient to estimate the mean density of wild boar. © 2017 Crown copyright. Pest Management Science © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

As pearling has been banned in Iran since 2006, stocks of pearl oysters has not been investigated during these years therefore, condition of natural habitats for Pinctada radiata in its old habitats was surveyed in present research. Shallow waters around Hendorabi Island were searched with diving and two habitats namely âSoolehâ and âSahel-e-sheniâ, were considered for study. The pearl oysters had most distribution in these habitats in depth ranges of 7 to 12 m and 8 to 11 m, respectively. Total stock in Sooleh and Sahel-e-sheni was surveyed near 35700 and 12563 Pinctada radiata, respectively, of which 22% and 67% were catchable, respectively. Catch Per Unit of Area (CPUA) in Sooleh and Sahel-e-sheni habitats was estimated equal to 0.3 N/m2 in both habitats, and Catch Per Unit of Effort (CPUE) in these habitats was calculated equal to 59.5 N/hr and 50.3 N/hr, respectively. Results of this study demonstrated that area, stocks and CPUA for studied habitats were less than previous years. Despite of interdict of pearling in this region since 7 years ago, stock revival has done slowly.

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In this paper effect of static densification of treated paulownia on relationship between strength properties and density was investigated. Specimens were steamed at 130 and 170oc and immediately were compressed to 35% and 45% of their original thickness in radial direction. Mechanical properties such as bending strength, brinell surface hardness and compression strength in axial and radial direction were determined for non-densified and densified wood. Indexes of density, strength, quality and strength potential were calculated to study the relationship between strength and density. The results show that the density index and strength index and also strengths significantly increased with increase in densification but strength potential indexes decreased. Steam treatment at 130oc had a slight positive effect on the strengths and strength potential indexes as effect of softening the wood but the strength potential indexes and strengths decreased due to treatment of wood at 170oc. Generally, strength potential indexes of all tested mechanical properties show that strength of densified paulownia was lower compared to what had expected for non-densified paulownia from increasing density, which in turn demonstrate the cell walls were negatively affected by compression. Axial compression strength and brinell hardness were slightly affected by densification.

The paper deals with differences in determination of bored pile compressive resistance in Slovakia and Poland. Common procedures of determination of bored pile compressive resistance, applied in Slovakia and Poland, will be introduced. It will be shown in examples that various calculation procedures take into account various factors influencing pile compressive resistance in different way, therefore pile compressive resistances determined by various procedures will be different. It will be also shown, that underground water has strong impact on pile compressive resistances so reliable determination of its presence and its change during pile life can contribute to economic pile design. [ABSTRACT FROM AUTHOR]

Series of laboratory testing on the investigation of soil liquefaction using cyclic triaxial test had been carried out by researchers around the world but many of the results are contradictory. Thus, it is important to first determine the condition in which the clean sand is most susceptible to liquefaction, then only the liquefaction susceptibility of sand matrix soils could be compared and discussed under this specific condition. This paper presents the undrained behaviour of Johor sand and sand mixed with fines (kaolin) from cyclic triaxial tests. Stress controlled triaxial test apparatus was used to shear the isotropically consolidated soil samples under undrained two-way cyclic loading until the initiation of liquefaction. The liquefaction was defined based on: (i) excess pore pressure was equal to effective confining pressure or (ii) double amplitude strain of 5 % was reached, whichever was achieved first. The results of two-way cyclic triaxial tests on clean sand showed that besides the cyclic stress ratio, the liquefaction resistance of the sand under undrained loading was proportional to effective consolidation pressure and density index. The Johor sand was more liquefiable at its loose state and under low effective consolidation pressure, when subjected to earthquake loading. [ABSTRACT FROM AUTHOR]

The loading of natural and anthropogenic soils can be determined in the field by using dynamic probing tests. This method is based on the measurement of the resistance, which the studied soil poses on the probe tip when it penetrates the soil. The most typical probe tips are cylindrical, conical and rarely cross-shaped. The penetrometer penetrates the soil by a hammer with a given mass freely falling from the height required in the test. The penetration resistance is defined by the numbers of blows required to drive the penetrometer over the defined distance ( Nk), where k = 10, 15(20) or 30 cm. The paper presents the results of heavy dynamic probing tests DPH with a hammer mass of 50 kg and penetration depth up to 30 m, carried out in an anthropogenic made ground in order to determine the soil loading for the foundation of the designed building. [ABSTRACT FROM AUTHOR]

Forest management in the region of Zacualtipán, Hidalgo, Mexico, has focused in the last three decades on the cultivation of pure even-aged stands of Pinus patula, the native timber species of fastest growth and high commercial value. The rapid growth of P. patula requires appropriate management of stand density to properly schedule thinnings and optimize stands' rotation. In this study, we determined the maximum line size-density relationship or self-thinning considering the stochastic frontier regression and ordinary least squares approaches for Reineke and Yoda models. In the estimation, we used data derived from 42 permanent sampling plots of 400 m2. The best estimates of the self-thinning line were obtained using the stochastic frontier models Truncated-normal and Half-normal of Reineke and Yoda. On this basis, we set diagrams for tree density management, considering the relative stand density index of Reineke (SDI) and that of Yoda (YDI). The method of stochastic frontier regression enables to directly estimate the upper limit of self-thinning without resorting to the selective use of data, where the points in which mortality from self-thinning has not yet exhibited are excluded from the analysis. For SDI and YDI, stochastic setting suggests a more conservative mortality rate compared to least squares fit. The method also allows a more efficient use of data, and incorporates information from inventory plots without remeasurements. [ABSTRACT FROM AUTHOR]

Dense grape clusters have a high predisposition to bunch rot. An elongation of cluster stems could result in a loosening of the cluster structure. To achieve such an elongation, gibberellic acid (GA3; 10 ppm) was applied to Sauvignon blanc either when three, five, seven, nine, 11 or 13 leaves were unfolded or at full bloom in the 2010 season. In the present season, all applications led to stem elongation, a reduction of cluster compactness as well as a reduction of bunch rot severity. The density index proved to be an efficient tool to describe the predisposition of grape clusters to bunch rot. Best success was achieved if the application took place when seven leaves were unfolded. In the subsequent season (2011; the year following the year of application), the number of inflorescences per shoot, the length of the clusters, as well as the yield were considerably reduced, especially in the treatments with promising positive effects on the cluster structure and disease severity. Hence, the present study shows the loosening potential as well as the risk of pre-bloom gibberellic acid applications. Due to the observed negative resultant effects, the pre-bloom application of GA3 at the present concentration (10 ppm) cannot yet be recommended for practical use in Sauvignon blanc. [ABSTRACT FROM AUTHOR]