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The root-knot nematode, Meloidogyne javanica, is one of the most damaging plant-parasitic nematodes, affecting chickpea and causing substantial yield losses worldwide. The damage potential and population dynamics of this nematode in chickpea in Ethiopia have yet to be investigated. In this study, six chickpea cultivars were tested using 12 ranges of initial population densities (Pi) of M. javanica second-stage juveniles (J2): 0, 0.125, 0.25, 0.5, 1, 2, 4, 8, 16, 32, 64 and 128 J2 (g dry soil)−1 in a controlled glasshouse pot experiment. The Seinhorst yield loss and population dynamics models were fitted to describe population development and the effect on different measured growth variables. The tolerance limit (TTFW) for total fresh weight ranged from 0.05 to 1.22 J2 (g dry soil)−1, with corresponding yield losses ranging from 31 to 64%. The minimum yield for seed weight (mSW) ranged from 0.29 to 0.61, with estimated yield losses of 71 and 39%. The ‘Haberu’ and ‘Geletu’ cultivars were considered good hosts, with maximum population densities (M) of 16.27 and 5.64 J2 (g dry soil)−1 and maximum multiplication rate (a) values of 6.25 and 9.23, respectively. All other cultivars are moderate hosts for M. javanica; therefore, it is crucial to initiate chickpea-breeding strategies to manage the tropical root-knot nematode M. javanica in Ethiopia. [ABSTRACT FROM AUTHOR]

Purpose: To present the process undertaken by our institute in commissioning Mobius3D (M3D) for patient‐specific quality assurance. Method: 168 plans were randomly selected to compare dose distribution measured with ArcCheck and dose calculated from M3D, both compared against the treatment planning system (TPS). The gamma criteria for measurement and M3D are 3%/2 mm with 10% and 50% dose thresholds, respectively. The effect of tissue inhomogeneity was investigated on 11 plans by recalculating the dose in M3D on a homogeneous phantom. Tolerance and action limits were established following the AAPM Task Group 218 recommendations. Results: The M3D showed high variability in gamma passing rate compared to the measurement. Twenty‐three out of 168 plans had false negative dose comparisons. These plans fall under high tissue inhomogeneity like lung and metal implants, small field targets, and breast plans planned with high energy. One false negative case (0.6%) was observed. A single tolerance limit of 91% and 92% gamma passing rate for the M3D and measurement‐based PSQA were established, respectively. Against the expectation, recalculating plans on the homogeneous phantom in M3D did not necessarily increase the gamma passing rate. These plans have a duty cycle >4.2, and the small field sizes combined with differences in slice thickness contributed to observed dose differences in the homogeneous phantom comparisons. Conclusion: Following the commissioning, M3D is adopted in our institute. Currently, the gamma criteria used for measurement and M3D are 3%/2 mm, 40% dose threshold, with gamma passing rates of 92% and 95%, respectively. A higher passing rate for M3D is adopted until more data is available. The combined effect of plan modulation, the field sizes, the tissue inhomogeneity, the dose algorithm, and the volume averaging effect from differences in slice thickness can contribute to the differences in dose in M3D and TPS. [ABSTRACT FROM AUTHOR]

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Meloidogyne spp. are an important threat to horticulture and cause substantial yield losses. Plant resistance is an alternative control method for chemical nematicides. This study highlights the host suitability of the lettuces cultivars Grand Rapids and Salinas 88 and the beans cultivars Aporé, Cornell 49242, Macarrão Atibaia and Ouro Negro to four Meloidogyne incognita and seven M. javanica isolates from Spain in a pot experiment. Moreover, the response of these cultivars to increasing M. incognita densities (Pi) was assessed in a plastic greenhouse. The lettuce cultivar Regina 71 and the bean cultivar Bolinha were included as susceptible standards for comparison. It was found that Grand Rapids and Salinas 88 lettuces were resistant to the most nematode isolates in the pot experiment but were classified as slightly and moderately resistant, respectively, in the plastic greenhouse at increasing Pi. Regarding the beans, Aporé was resistant to the majority of the Meloidogyne isolates whereas Macarrão Atibaia and Ouro Negro were slightly resistant and Cornell 49242 was susceptible in the pot experiment. In the plastic greenhouse, Aporé was the only cultivar able to effectively suppress the nematode reproduction irrespective of Pi, while Ouro Negro became less resistant as Pi increased. These results play an important role in enhancing the effective and ecofriendly Meloidogyne management strategies. [ABSTRACT FROM AUTHOR]

The requirements for the quality, reliability, and cost-effectiveness of engineering products and engineering production itself are constantly improving. As a result, there is an increasing demand for the quality of design and technological preparation of production, which includes classical dimensional analysis as its foundation. The Classical Method of dimensional analysis calculation represents a comprehensive set of computational and analytical actions carried out during the development and analysis of projects and technological processes, including: the construction of specialized dimensional diagrams for projects and technological processes, the identification and recording of interconnections between all dimensional parameters, the identification of dimensional chains, verification, and the establishment of rational sizing methods in drawings. Dimensional analysis involves a significant number of procedures and actions. The time required for dimensional analysis is substantial, ranging from 10 to 50 hours for a single technical drawing or technological process. At the same time, the use of Modern Methods for calculating dimensional chains will allow us to determine, after a thorough evaluation of manufacturing conditions at each production stage (operation), leading to a reduction in the manufacturing cost of parts. The increased workload of the evaluation process can be compensated by using databases and appropriate software that operates interactively with the user. This will also lead to a reduction in the labor intensity of dimensional analysis of projects and technological processes through automation.

Summary: Finger millet (Eleusine coracana) is a staple crop for subsistence farmers and is primarily cultivated in arid and semi-arid regions. Nevertheless, there are limited data available on the occurrence of plant-parasitic nematodes that specifically target finger millet, and the damage arising from such infections. In this study, we investigated the population dynamics, damage threshold and tolerance of the lesion nematode, Pratylenchus n. sp., and the root-knot nematode, Meloidogyne javanica , on finger millet 'P-224'. We used 11 initial population densities (P i) of second-stage juveniles (J2): 0, 0.125, 0.25, 0.5, 1, 2, 4, 8, 16, 32 and 64 J2 (g soil)−1 for M. javanica and the same densities of mixed life-stages for Pratylenchus n. sp. The logistic growth model, Seinhorst yield loss and population dynamic models were fitted to the shoot height, plant biomass and final nematode population density. Based on the population dynamics model parameters, maximum multiplication rates and maximum population densities for each nematode species were estimated. The maximum multiplication rates (a) were 32.39 and 17.46, whilst the maximum population densities (M) were 18.83 nematodes (g soil)−1 and 19.78 J2 (g soil)−1 for Pratylenchus n. sp. and M. javanica respectively. The maximum height reached (C) was negatively affected by increasing P i for both nematode genera, while the rate of growth (B) and the time to reach 0.5 × C was not affected based on the logistic model. A tolerance limit (T) of 1.70 nematodes (g soil)−1 and 0.65 J2 (g soil)−1; relative minimum grain yield (m) of 0.23 and 0.40 for Pratylenchus n. sp. and M. javanica was found, respectively. The results indicate that 'P-224' is a good host for both Pratylenchus n. sp. and M. javanica , which significantly reduce yield. These findings can be used as a base to develop effective nematode management strategies for finger millet. [ABSTRACT FROM AUTHOR]

This study uses statistical quality control (SQC) and overall equipment effectiveness (OEE) to examine quality at a porcelain production firm. The study is motivated by the most frequently broken machines in 2019, is the Jigger 01 machine. This paper aims to evaluate the machine's effectiveness using the OEE method. The OEE determines the scope of the problem to be solved using the SQC method. The average OEE value in 2019 was 70%. Based on the SQC method, the product defect produced is still under control. However, the average defect is still above the company's tolerance limit of 10%. Consequently, this study offers enhancements utilizing the Failure Mode Effect Analysis (FMEA) technique. The results indicate that human resources and machines caused defective products. This paper contributes to providing several improvements that the company can apply to maximize its quality control analysis. After implementing the improvement, the OEE value increases to 74%. [ABSTRACT FROM AUTHOR]

Environmental changes related to global warming are both a threat to cold-water fishes and simultaneously create favourable conditions for the spread of eurythermic or warm-water species. In both cases, it is necessary to develop conservation strategies supported by precise ecological data, including thermal requirements. In this study, we determined the upper thermal tolerance thresholds and the critical maxima for three small, non-commercial Eurasian freshwater fish species; i.e. lake minnow Eupallasella (=Rhynchocypris) percnurus, sunbleak Leucaspius delineatus and topmouth gudgeon Pseudorasbora parva using the Critical Thermal Method at different acclimation temperatures, i.e. 18, 23, 28, and 33°C (highest treatment for topmouth gudgeon only). We hypothesized that lake minnow would have the lowest thermal tolerance and the topmouth gudgeon the highest. The response to temperature rise and the upper thermal limits were species-specific and correlated with the acclimation temperature, but not with fish length. Sunbleak showed the lowest thermal tolerance, though at 28°C both E. percnurus and L. delineatus reached a similar critical thermal limit. Topmouth gudgeon showed distinctly higher upper thresholds of thermal tolerance and at the highest acclimation temperature the critical upper limit for the species was close to 42°C. The results obtained for L. delineatus were surprising as we predicted that this leuciscid fish would be more tolerant of high temperatures than E. percnurus. We discuss the results in relation to the threat of extinction and the risk of species spreading beyond their natural range in the context of a warming environment.

Ponds are known to have greater biodiversity of species. They are the habitats of many aquatic animals and plants. The purpose of the study is to compare the water quality of the Temple Pond to give a reference for conservation management for this aquatic species and help improve water quality and aquatic biodiversity. Temple Pond is located opposite Bara Talab near Main Road of Lohardaga town of Jharkhand. It is a habitat of fishes – mostly carp. For the study of physicochemical parameters of the pond, water samples were collected for three periods of the year, i.e. pre-monsoon (May), monsoon (August), and post-monsoon (November) for two consecutive years (2015–2016). Samples were stored according to the preservation procedure followed by AS/NZS 5667.1:1998, and analysis was done using standard procedure. Major water parameters such as pH (7.20–7.40), Total Hardness (35.60–61.20), Nitrate (mg/L) (1.10–2.40), Chloride (mg/L) (22.00–33.00), Fluoride (mg/L) (0.02–0.04) were recorded low value; however, Dissolved oxygen (D.O) (mg/L) (4.10–6.90) and Biochemical oxygen demand (B.O.D) (mg/L) (2.50–4.20) were little higher than Standard Tolerance limit per classified use of water class depending on various uses of water (ISI-IS: 2296–1982), revealed that the pond is suitable for outdoor bathing (Class-B) and D – Fish culture and aquatic life propagation.

BACKGROUND: Oryzophagus oryzae (Costa Lima) (Coleoptera: Curculionidae) is a major pest of flooded rice paddies throughout South America, and species with very similar life histories are present in many rice‐producing regions of the world (collectively rice water weevils, RWWs). The damage caused by RWW larvae on rice cultivars with contrasting levels of resistance ('BRS Pampa CL'= 'Pamp': susceptible, 'BRS Atalanta' = 'Atal': resistant‐antibiosis) was evaluated in two consecutive years in the field under seven infestation levels: 0, 2, 4, 6, 8, 10 and 20 adult couples per cage with plants. RESULTS: Higher densities of adults increased the number of leaf‐feeding scars and larvae on roots, respectively, at the rate ≤2.14 and 2.75 in Pamp and 2.23 and 2.48 in Atal, with the total number of larvae generated being lower in Atal. Grain yield was negatively impacted with increasing larval density on the roots, mainly by decreasing root volume and the number of grains per panicle. Root injury intensity and yield loss showed a nonlinear relationship. It was found that significant yield losses occurred with 8.37 larvae per plant in Pamp and 9.80 larvae per plant in Atal CONCLUSION: The results provided the first evidence of a tolerance limit for RWW larval damage that, even though similar between cultivars of contrasting resistance, corresponds to twice the current conventional level for larval control in Brazil. We also discuss here the potential of applying tolerance limits to manage the RWW adult population in rice fields. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Soil salinization is an important environmental problem worldwide and has a significant impact on the growth of plants. In recent years, the mechanisms of plant salt tolerance have received extensive attention from researchers. In this paper, an experiment was implemented to assess the potential effect of different NaCl and NaHCO3 (sodium bicarbonate—an alkaline salt) concentrations (25 mmol·L−1, 50 mmol·L−1, 100 mmol·L−1, 150 mmol·L−1 and 200 mmol·L−1) on the growth, antioxidant enzymes, osmoprotectants, photosynthetic pigments and MDA of Viola tricolor L. to reveal the physiological response and explore the maximum concentrations of NaCl and NaHCO3 stress that V. tricolor can tolerate. The results showed that NaCl and NaHCO3 treatments had significant effects on osmoprotectants, antioxidant enzymes, photosynthetic pigments, MDA content and the plant height growth of V. tricolor. On day 14 of the NaCl and NaHCO3 stress, the height growth of V. tricolor was significantly greater than CK when the concentration of NaCl and NaHCO3 was less than 100 mmol·L−1. Soluble protein (SP) was significantly greater than CK when the NaCl concentration was less than 150 mmol·L−1 and the NaHCO3 concentration was less than 200 mmol·L−1; soluble sugar (SS) was significantly greater than CK under all NaCl and NaHCO3 treatments; proline (Pro) was significantly greater than CK when the NaCl concentration was 150 mmol·L−1 and the NaHCO3 concentration were 150 and 200 mmol·L−1, respectively. Peroxidase (POD) was significantly greater than CK when the NaCl concentration was less than 200 mmol·L−1 and the NaHCO3 concentration was less than 150 mmol·L−1; superoxide dismutase (SOD) was significantly greater than CK when the NaCl concentration was 50 mmol·L−1 and the NaHCO3 concentrations were 50, 100 and 150 mmol·L−1, respectively; catalase (CAT) was significantly greater than CK when the NaCl and NaHCO3 concentrations were 25, 50 and 100 mmol·L−1, respectively. Chlorophyll (Chl) was significantly lower than CK when the NaCl and NaHCO3 concentrations were greater than 100 mmol·L−1. Malondialdehyde (MDA) gradually increased with the increase in the NaCl and NaHCO3 concentrations. Membership function analysis showed that the concentrations of NaCl and NaHCO3 that V. tricolor was able to tolerate were 150 mmol·L−1 and 200 mmol·L−1, respectively. Beyond these thresholds, osmoprotectants and antioxidant enzymes were seriously affected, Chl degradation intensified, the photosynthetic system was seriously damaged, and the growth of V. tricolor was severely affected. According to a comprehensive ranking of results, the degree of NaCl stress on V. tricolor was lower than that from NaHCO3 when the treatment concentration was lower than 50 mmol·L−1, but higher than that from NaHCO3 when it exceeded 50 mmol·L−1. [ABSTRACT FROM AUTHOR]

Environmental changes related to global warming are both a threat to cold-water fishes and simultaneously create favourable conditions for the spread of eurythermic or warm-water species. In both cases, it is necessary to develop conservation strategies supported by precise ecological data, including thermal requirements. In this study, we determined the upper thermal tolerance thresholds and the critical maxima for three small, non-commercial Eurasian freshwater fish species; i.e. lake minnow Eupallasella (=Rhynchocypris) percnurus, sunbleak Leucaspius delineatus and topmouth gudgeon Pseudorasbora parva using the Critical Thermal Method at different acclimation temperatures, i.e. 18, 23, 28, and 33°C (highest treatment for topmouth gudgeon only). We hypothesized that lake minnow would have the lowest thermal tolerance and the topmouth gudgeon the highest. The response to temperature rise and the upper thermal limits were species-specific and correlated with the acclimation temperature, but not with fish length. Sunbleak showed the lowest thermal tolerance, though at 28°C both E. percnurus and L. delineatus reached a similar critical thermal limit. Topmouth gudgeon showed distinctly higher upper thresholds of thermal tolerance and at the highest acclimation temperature the critical upper limit for the species was close to 42°C. The results obtained for L. delineatus were surprising as we predicted that this leuciscid fish would be more tolerant of high temperatures than E. percnurus. We discuss the results in relation to the threat of extinction and the risk of species spreading beyond their natural range in the context of a warming environment. [ABSTRACT FROM AUTHOR]

A mortar is commonly used as an indirect firing weapon to support close fires with a variety of ammunition. There are mortar weapons with various shells. Each type of shells fired by mortars does damage to a weapon when the total damage on a mortar weapon reaches the tolerance limit, the mortar weapon either fails or explodes, leading to a compulsory replacement which is costly. In order to maintain the mortar weapons and archers in wars, a research was conducted to find the best number of mortar shells that will be fired until a preventive replacement for mortar weapons is implemented. [ABSTRACT FROM AUTHOR]

The conventional way to characterize the proportion of non-conforming parts in a process is to calculate process capability indices and transform them into a ratio. These widely used indices are able to give digestible information about the ratio of non-conforming parts if some assumptions are fulfilled. A correct estimation method should be based on the output distribution of the process, and the uncertainty of the parameter estimates should be considered, as well. In this article, a special case of the output distribution is examined: a mixture of normal distributions is considered. In practice, this output distribution appears if a multiple stream process is investigated. The novelty of this study is to apply the tolerance interval-based estimation method for the proportion of non-conforming parts in a case study of a multiple stream process and to qualify the limitations of the proposed estimation method. A simulation study is performed to investigate the bias, mean square error, and root mean square error of the estimates from the two estimation methods (process performance index-based and tolerance interval-based) for different sample sizes for each stream (N). It was found that, if it may be assumed that the speed of the streams is equal in the case of the sample sizes investigated (N = 25, 50, 100 per head), the proposed (tolerance interval-based) method overestimates the proportion of non-conforming parts while the conventional (process performance index-based) method underestimates it. The tolerance-limit based estimation method has asymptotically better properties than the process performance index-based estimation method. [ABSTRACT FROM AUTHOR]

Objective: To test the basic dosimetry characteristics of a new high-resolution matrix and to perform a preliminary study on the three-dimensional (3D) dose verification of intensity-modulated treatment (IMRT). Methods: The dosimetry characteristics of the new matrix were investigated, including repeatability, dose-rate response, and dose linearity. Twenty cases of nasopharyngeal carcinoma (NPC) and 20 cases with lung cancer were randomly selected for IMRT plans, and the novel matrix was employed for 3D dose verification. The measured results were evaluated using the gamma passing rate (GPR) and dose volume histogram (DVH). The action limit (AL) and tolerance limit (TL) of the target volume and each organ at risk (OAR) were calculated with reference to the American Association of Physicists in Medicine (AAPM) TG218 report. Results: The matrix performed well for all dosimetry characteristic tests, with a deviation of 90% under the relatively strict standard of 2%/2 ​mm. The DVH showed that the measurement results of D98 and D95 for the target volumes were slightly lower and D2 were higher than those of treatment planning system (TPS) (P ​

Purpose: Establishing the tolerance limits of patient‐specific quality assurance (PSQA) processes based on the gamma passing rate (GPR) by using normal statistical process control (SPC) methods involves certain problems. The aim of this study was threefold: (a) to show that the heuristic SPC method can replace the quantile method for establishing tolerance limits in PSQA processes and is more robust, (b) to introduce an iterative procedure of "Identify‐Eliminate‐Recalculate" for establishing the tolerance limits in PSQA processes with unknown states based on retrospective GPRs, and (c) to recommend a workflow to define tolerance limits based on actual clinical retrospective GPRs. Materials and Methods: A total of 1671 volumetric‐modulated arc therapy (VMAT) pretreatment plans were measured on four linear accelerators (linacs) and analyzed by treatment sites using the GPRs under the 2%/2 mm, 3%/2 mm, and 3%/3 mm criteria. Normality testing was performed using the Anderson‐Darling (AD) statistic and the optimal distributions of GPRs were determined using the Fitter Python package. The iterative "Identify‐Eliminate‐Recalculate" procedure was used to identify the PSQA outliers. The tolerance limits of the initial PSQAs, remaining PSQAs after elimination, and in‐control PSQAs after correction were calculated using the conventional Shewhart method, two transformation methods, three heuristic methods, and two quantile methods. The tolerance limits of PSQA processes with different states for the respective methods, linacs, and treatment sites were comprehensively compared and analyzed. Results: It was found that 75% of the initial PSQA processes and 63% of the in‐control processes were non‐normal (AD test, p < 0.05). The optimal distributions of GPRs for the initial and in‐control PSQAs varied with different linacs and treatment sites. In the implementation of the "Identify‐Eliminate‐Recalculate" procedure, the quantile methods could not identify the out‐of‐control PSQAs effectively due to the influence of outliers. The tolerance limits of the in‐control PSQAs, calculated using the quantile of optimal fitting distributions, represented the ground truth. The tolerance limits of the in‐control PSQAs and remaining PSQAs after elimination calculated using the heuristic methods were considerably close to the ground truth (the maximum average absolute deviations were 0.50 and 1.03%, respectively). Some transformation failures occurred under both transformation methods. For the in‐control PSQAs at 3%/2 mm gamma criteria, the maximum differences in the tolerance limits for four linacs and different treatment sites were 3.10 and 5.02%, respectively. Conclusions: The GPR distributions of PSQA processes vary with different linacs and treatment sites but most are skewed. In applying SPC methodologies to PSQA processes, heuristic methods are robust. For in‐control PSQA processes, the tolerance limits calculated by heuristic methods are in good agreement with the ground truth. For unknown PSQA processes, the tolerance limits calculated by the heuristic methods after the iterative "Identify‐Eliminate‐Recalculate" procedure are closest to the ground truth. Setting linac‐ and treatment site‐specific tolerance limits for PSQA processes is necessary for clinical applications. [ABSTRACT FROM AUTHOR]

Soil salinization is an important environmental problem worldwide and has a significant impact on the growth of plants. In recent years, the mechanisms of plant salt tolerance have received extensive attention from researchers. In this paper, an experiment was implemented to assess the potential effect of different NaCl and NaHCO3 (sodium bicarbonate—an alkaline salt) concentrations (25 mmol·L−1, 50 mmol·L−1, 100 mmol·L−1, 150 mmol·L−1 and 200 mmol·L−1) on the growth, antioxidant enzymes, osmoprotectants, photosynthetic pigments and MDA of Viola tricolor L. to reveal the physiological response and explore the maximum concentrations of NaCl and NaHCO3 stress that V. tricolor can tolerate. The results showed that NaCl and NaHCO3 treatments had significant effects on osmoprotectants, antioxidant enzymes, photosynthetic pigments, MDA content and the plant height growth of V. tricolor. On day 14 of the NaCl and NaHCO3 stress, the height growth of V. tricolor was significantly greater than CK when the concentration of NaCl and NaHCO3 was less than 100 mmol·L−1. Soluble protein (SP) was significantly greater than CK when the NaCl concentration was less than 150 mmol·L−1 and the NaHCO3 concentration was less than 200 mmol·L−1; soluble sugar (SS) was significantly greater than CK under all NaCl and NaHCO3 treatments; proline (Pro) was significantly greater than CK when the NaCl concentration was 150 mmol·L−1 and the NaHCO3 concentration were 150 and 200 mmol·L−1, respectively. Peroxidase (POD) was significantly greater than CK when the NaCl concentration was less than 200 mmol·L−1 and the NaHCO3 concentration was less than 150 mmol·L−1; superoxide dismutase (SOD) was significantly greater than CK when the NaCl concentration was 50 mmol·L−1 and the NaHCO3 concentrations were 50, 100 and 150 mmol·L−1, respectively; catalase (CAT) was significantly greater than CK when the NaCl and NaHCO3 concentrations were 25, 50 and 100 mmol·L−1, respectively. Chlorophyll (Chl) was significantly lower than CK when the NaCl and NaHCO3 concentrations were greater than 100 mmol·L−1. Malondialdehyde (MDA) gradually increased with the increase in the NaCl and NaHCO3 concentrations. Membership function analysis showed that the concentrations of NaCl and NaHCO3 that V. tricolor was able to tolerate were 150 mmol·L−1 and 200 mmol·L−1, respectively. Beyond these thresholds, osmoprotectants and antioxidant enzymes were seriously affected, Chl degradation intensified, the photosynthetic system was seriously damaged, and the growth of V. tricolor was severely affected. According to a comprehensive ranking of results, the degree of NaCl stress on V. tricolor was lower than that from NaHCO3 when the treatment concentration was lower than 50 mmol·L−1, but higher than that from NaHCO3 when it exceeded 50 mmol·L−1.

In glasshouses practising monoculture of butterhead lettuce in Belgium, high densities of pin nematodes (Paratylenchus spp.) are frequently associated with reduced plant growth. Growers currently apply chemical soil disinfestation measures to manage this problem, although stricter phytosanitary regulations are forcing a shift towards integrated management. Efficient implementation of such management requires knowledge about the factors influencing nematode population dynamics, and the damage threshold for lettuce. The nematode populations in five Belgian glasshouses were monitored for at least 1 year by frequently soil sampling at 0–30 cm and 30–60 cm depth. An undescribed species of Paratylenchus was identified in all glasshouses based on morphological and molecular features. High nematode densities (>20,000 (100 ml soil)−1) occurred in winter and spring. Chemical soil disinfestation lowered these populations greatly, although up to 14% survived in the deeper soil layer. After soil steaming under negative pressure, no pin nematodes were found. After 2 months of black fallow pin nematode densities were reduced by 50%–76%. Lamb's lettuce, parsley and wild rocket were found to be poor hosts in a pot experiment, while reproduction factors (Pf/Pi) on lettuce cultivars varied between 1 and 3. In three experiments with butterhead lettuce 'Cosmopolia' in pots with a series of 9 or 10 densities of Paratylenchus sp. [up to 35,000 (100 ml soil)−1], no damage to lettuce heads was observed. However, root weight and root quality were reduced, and the corresponding damage thresholds were rather low [1,754 and 362 Paratylenchus sp. (100 ml soil)−1, respectively]. Management strategies such as crop rotation, soil disinfestation or fallow are recommended to avoid pin nematode population build‐up. [ABSTRACT FROM AUTHOR]

Summary: The root-lesion nematode, Pratylenchus penetrans , causes growth reduction in glasshouse-grown lettuce and is mainly controlled by chemical soil disinfestation. Integrated management strategies require more knowledge about the population dynamics and damage threshold densities. We monitored the population during 2.5 years in a commercial glasshouse by sampling soil in the same four 1 m2 spots at 0-30 cm and 30-60 cm depth. The grower grew lettuce in rotation with leek, applied 1,3-dichloropropene in summer and left the field fallow during winter. Growing leek reduced the nematode population slightly but chemical soil disinfestation lowered the numbers drastically, although 41% of the nematodes in the deeper layer survived. Black fallow resulted in a slight increase of the population, probably due to hatching. Two pot experiments with ten densities of P. penetrans were conducted to estimate the damage threshold for a summer and autumn cultivar ('Cosmopolia' and 'Brighton', respectively). The thresholds for lettuce weight were 669 and 3834 P. penetrans (100 ml soil)−1 in summer and autumn, respectively, but with considerable variability in estimated parameters. The thresholds for root damage were much lower: 204 and 48 P. penetrans (100 ml soil)−1. Nematode numbers did not increase on lettuce in the pot tests (maximum multiplication rate was 0.40) but increased slightly in the commercial setting. These results show that populations of P. penetrans build up slowly when butterhead lettuce is rotated with leek and fallow, but chemical soil disinfestation is required to avoid numbers resulting in root damage. [ABSTRACT FROM AUTHOR]

Higher Education is in the centre of interest in this era of Outcome Based Education (OBE) in learning centric environment due to in quest of better human life and living and further improvement in technological aspects. The main challenges remain in providing resource persons in quest of optimum knowledge transfer to address quality concern right from career opportunities to continuing education programs. So opening up new academic departments to address the societal needs is a regular process in parallel to resource enhancement in the existing departments, keeping balance with the increasing number of students. In this problem, there are inherent uncertainties in terms of resignation and retention of the resource persons due to their own interest. That's the reason why most of the teaching organizations encounter the difficulties of resource allocation of teaching personnel in the academic departments. The objective of this proposed work is to demonstrate how the Genetic Algorithm (GA) is applied in goal programming (GP) formulation of the problem for university resource planning of academic personnel to different departments for enhancement of academic standards of a university on a long-term basis in the planning process. In model formulation, the number of Professor, Associate Professor, Assistant Professor, Visiting/Part-Time faculty member and Non-teaching staff along with the budget goals of each of the academic departments are identified and described. In the solution process, the ideais to employ GA to the goal programming (GP) construction of academic resource planning problems with fractional goals and target intervals in university management system. [ABSTRACT FROM AUTHOR]

Most models reported in the current process target literature assume a nominal-the-best type quality characteristic in determining the optimal process mean value. In real-world industrial settings, however, a number of quality characteristics of interest are of a larger-the-better type ( L -type), and the problem of jointly determining the optimum process mean and tolerance limit for the L -type quality characteristic may be of significant practical importance, yet this has largely been overlooked in the literature. In this paper, cost-effective optimization models are developed, and the methods of finding optimum solutions are presented. Numerical examples and sensitivity analysis are given. [ABSTRACT FROM AUTHOR]

Several experiments were carried out to assess the performance of commercial Solanum torvum cultivars against the root knot nematodes Meloidogyne incognita and M. javanica in Spain. The response of S. torvum rootstock cultivars Brutus, Espina, Salutamu and Torpedo against M. incognita and Mi‐1.2 (a)virulent M. javanica isolates was determined in pot experiments, and of 'Brutus' to an N‐virulent isolate of M. incognita, compared with that of the eggplant S. melongena 'Cristal'. The relationship between the initial and final population densities of M. javanica on ungrafted and grafted 'Cristal' onto the S. torvum 'Brutus' was assessed, together with the effect on dry shoot biomass. Finally, the population growth rate and the resistance level of the four S. torvum cultivars against M. incognita was assessed under plastic greenhouse conditions in two cropping seasons. All S. torvum rootstocks responded as resistant to the M. incognita isolates and from highly resistant to susceptible against M. javanica isolates. The maximum multiplication rates of M. javanica on the ungrafted or grafted eggplant were 270 and 49, respectively, and the equilibrium densities were 1318 and 2056 eggs and J2 per 100 cm3 soil, respectively. The tolerance of the ungrafted eggplant was 10.9 J2 per 100 cm3 soil, and the minimum relative dry shoot biomass was 0.76. The population growth rate of M. incognita on eggplant cv. Cristal differed from that of the S. torvum cultivars in both cropping seasons. These results suggest that S. torvum is a valuable rootstock for managing the two Meloidogyne species irrespective of the (a)virulence status. [ABSTRACT FROM AUTHOR]

Abstract The best-estimate plus uncertainty method has been widely used in safety analysis for nuclear power plants. In this method, it is very important to have a sound uncertainty propagation method which should model the propagation of both epistemic and aleatory uncertainties and provide clear interpretation of the result. A typical example of such methods for nuclear application is the order statistics method based on Wilks' formula. This method requires practically small number of simulations to obtain the desired tolerance limit and the number is independent of the number of uncertainty parameters. In addition, since the method is based on non-parametric statistics, the conclusions drawn by the method should have distribution-free characteristics. This study aims at assessing the characteristics of the order statistics method based on Wilks' formula by means of numerical experiments and focuses on one-sided test which is typically used for safety evaluation. The distribution-free characteristics have been assessed by using 21 trial distributions and fully random samples out of all trial distributions. The effect of the order of Wilks' formula on the estimated tolerance limit is investigated by examining the characteristics of the results from various orders. The analysis results clearly confirm the order-free and distribution-free characteristics of the tolerance limit estimated by the order statics method based on Wilks' formula. In addition, it is found that the application of higher-order Wilks' formula is recommended in order to achieve less conservative and sensitive tolerance limit. Highlights • The validity of Wilks' formula was assessed by means of numerical experiments. • Order- and distribution-free characteristics is confirmed. • A lower-order formula is more likely to result in a more conservative tolerance limit. [ABSTRACT FROM AUTHOR]

Maize is one of the most important cereal crop species due to its uses for human and cattle nourishment, as well as its industrial use as a raw material. The yield and grain quality of maize depend on plant establishment, which starts with germination. Germination is dependent on embryo vigor and the stored reserves in the scutellum and endosperm. During germination, the scutellum epidermis changes and secretes enzymes and hormones into the endosperm. As a result, the hydrolysis products of the reserves and the different soluble nutrients are translocated to the scutellum through epithelial cells. Then, the reserves are directed to the embryo axis to sustain its growth. Therefore, the microenvironment surrounding the scutellum modulates its function. Zinc (Zn) is a micronutrient stored in the maize scutellum and endosperm; during imbibition, Zn from the endosperm is solubilized and mobilized towards the scutellum. During this process, Zn first becomes concentrated and interacts with cell wall charges, after which excess Zn is internalized in the vacuole. Currently, the effect of high Zn concentrations on the scutellum function and germinative processes are not known. In this paper, we show that, as a function of the concentration and time of exposure, Zn causes decreases in the radicle and plumule lengths and promotes the accumulation of reactive oxygen species (ROS) and flavonoids as well as changes in the activity of the cell wall Class III peroxidase (POD), which was quantified with guaiacol or catechin in the presence of H2O2. The relationship between the activity index or proportion of POD activity in the scutellum and the changes in the flavonoid concentration is proposed as a marker of stress and the state of vigor of the embryo.

Predicting the damage caused by certain nematode population densities is crucial in deciding whether or not to cultivate pepper and selecting the most suitable management strategies. To understand the relationship between the initial nematode density (Pi) and the final nematode population (Pf), and the damage potential of Meloidogyne incognita to var. Dinsire, a study was conducted under greenhouse conditions. A geometric series of 13 initial densities (0, 0.0625, 0.125, 0.25, 0.5, 1, 2, 4, 8, 16, 32, 64, 128 J2 (g soil)-1) of M. incognita was subjected to Dinsire. The treatments were arranged in a randomized complete design with four replications and terminated after 120 days of nematode inoculation. This study showed that the final nematode population, plant growth, and yields decreased as initial nematode inoculums increased. Maximum suppression fresh weight of shoot (43.8%) and fruit (52%) was recorded at Pi ≥ 8 J2 (g soil)-1. The analysis of Seinhorst's yield loss model indicated the highest tolerance limit (T=0. 64 egg + J2 (g soil)-1) recorded for leaf number, while the relative minimum yield (m) of 0.91 and 0. 86 were the highest m values for root length and shoot height, respectively. Furthermore, the maximum multiplication rate (a) and population densities (M) were estimated as 8813.2 and 3420.1 (eggs and J2 (g soil)-1), respectively. Therefore, evaluating hot pepper varieties for resistance using a wide range of Pi could generate more reliable information on the host status of pepper varieties. [ABSTRACT FROM AUTHOR]

Meloidogyne spp. are an important threat to horticulture and cause substantial yield losses. Plant resistance is an alternative control method for chemical nematicides. This study highlights the host suitability of the lettuces cultivars Grand Rapids and Salinas 88 and the beans cultivars Aporé, Cornell 49242, Macarrão Atibaia and Ouro Negro to four Meloidogyne incognita and seven M. javanica isolates from Spain in a pot experiment. Moreover, the response of these cultivars to increasing M. incognita densities ( Pi ) was assessed in a plastic greenhouse. The lettuce cultivar Regina 71 and the bean cultivar Bolinha were included as susceptible standards for comparison. It was found that Grand Rapids and Salinas 88 lettuces were resistant to the most nematode isolates in the pot experiment but were classified as slightly and moderately resistant, respectively, in the plastic greenhouse at increasing Pi. Regarding the beans, Aporé was resistant to the majority of the Meloidogyne isolates whereas Macarrão Atibaia and Ouro Negro were slightly resistant and Cornell 49242 was susceptible in the pot experiment. In the plastic greenhouse, Aporé was the only cultivar able to effectively suppress the nematode reproduction irrespective of Pi , while Ouro Negro became less resistant as Pi increased. These results play an important role in enhancing the effective and ecofriendly Meloidogyne management strategies.

Abstract The application of identical exposure dosages in different species generally leads to a limited understanding of dose-response patterns because of species-specific factors. To evaluate phenol-induced ecotoxicity, antioxidant enzyme activity and population growth dynamics were compared in two model ciliates, the marine species Euplotes vannus and the freshwater species Paramecium multimicronucleatum. Dosage ranges of phenol exposure were based on tolerance limits of test ciliates as determined by their carrying capacity (K) and growth rate (r). When the exposure duration of phenol increased from 48 h to 96 h, the median effective dose (ED 50) for P. multimicronucleatum decreased faster than that for E. vannus , and the ratio of the former to the latter declined from 2.75 to 0.30. When E. vannus was exposed to increasing concentrations of phenol (0–140 mg l−1), r rose initially and then dropped significantly at concentrations higher than 40 mg l−1, whereas K decreased linearly over the entire range. For P. multimicronucleatum, both r and K declined gradually over the range 0–200 mg l−1 phenol. Dose-response patterns of activities of three individual antioxidant enzymes, and the integrative index of the three enzymes, presented a biphasic (inverse U-shaped) curve at each of four durations of exposure, i.e. 12 h, 24 h, 36 h and 48 h. Cluster analyses and multidimensional scaling analyses of antioxidant enzyme activities revealed differences in the temporal succession of physiological states between the two model ciliates. In brief, combining ED 50 with growth dynamic parameters is helpful for designing exposure dosages of toxicants in ecotoxicity tests. Highlights • Phenol-induced ecotoxicity was studied in two model ciliates. • Dosage ranges were determined by tolerance limits from population growth dynamics. • Dose-response presented inverse U-shaped curve when dose reached tolerance limit. • Specific response mechanisms to phenol were different in the two test ciliates. • Combining ED 50 with growth dynamic parameters is helpful in ecotoxicity tests. [ABSTRACT FROM AUTHOR]

The present work investigates the corrosion behaviour of magnesium with different Fe contents. It is found that the micro-galvanic coupling between Fe-rich particles and magnesium matrix results in surface film formation and decrease in anodic reaction rate, consequently, increase of corrosion potential. Depending on the population density of Fe-rich particle, if the corrosion potential increases to the breakdown potential of surface film, localized corrosion initiates at the sites of breakdown. It is observed that Mg with different Fe contents exhibit the same critical potential value for corrosion initiation. Thus, corrosion potential is a critical factor for the corrosion tolerance limit of Fe in Mg. [ABSTRACT FROM AUTHOR]