Effect of agitation speed on the density of bacteria Photorhabdus luminescens and the population dynamics of nematodes Heterorhabditis megidis in liquid culture

Abstract Liquid culture is the most scalable technology for the industrial production of entomopathogenic nematodes. Variability of the recovery after inoculation into cultures of Photorhabdus luminescens remains a persistent problem in the mass production of Heterorhabditis sp. In order to enhance infective juvenile (IJ) recovery and improve nematode population management, we analysed the correlation between the nematode Heterorhabditis megidis (strain KV – 136) development in liquid cultures, the density of bacteria of P. luminescens and the culture agitation speed. Analyses focused on the impact of different agitation speeds (160 rpm and 200 rpm) on the dynamics of population growth of H. megidis in liquid cultures at constant biotic and abiotic parameters (initial dose of nematodes introduced to the culture 2300 IJs/ml, temperature 25°C, the number of bacterial colonies 0.3 × 107/ml). The performed experiments showed that the agitation speed of 200 rpm favourably affected the density of bacteria of P. luminescens (24.14 × 107/ml). High density of bacteria at this agitation speed resulted in an earlier (on the fifth day of the culture) maximum increase in the number of hermaphroditic individuals (1239.6 H/ml) than in the culture at an agitation speed of 160 rpm.

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Uncontrolled Electric Vehicle Charging Impacts on Distribution Electric Power Systems with Primarily Residential, Commercial or Industrial Loads

Energies ◽

10.3390/en14061688 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1688 ◽

Cited By ~ 1

Author(s):

C. Birk Jones ◽

Matthew Lave ◽

William Vining ◽

Brooke Marshall Garcia

Keyword(s):

Power Systems ◽

Electric Power ◽

Low Voltage ◽

Peak Load ◽

Electric Power Systems ◽

Primary System ◽

Maximum Increase ◽

Actual Distribution ◽

The Impact ◽

Ev Charging

An increase in Electric Vehicles (EV) will result in higher demands on the distribution electric power systems (EPS) which may result in thermal line overloading and low voltage violations. To understand the impact, this work simulates two EV charging scenarios (home- and work-dominant) under potential 2030 EV adoption levels on 10 actual distribution feeders that support residential, commercial, and industrial loads. The simulations include actual driving patterns of existing (non-EV) vehicles taken from global positioning system (GPS) data. The GPS driving behaviors, which explain the spatial and temporal EV charging demands, provide information on each vehicles travel distance, dwell locations, and dwell durations. Then, the EPS simulations incorporate the EV charging demands to calculate the power flow across the feeder. Simulation results show that voltage impacts are modest (less than 0.01 p.u.), likely due to robust feeder designs and the models only represent the high-voltage (“primary”) system components. Line loading impacts are more noticeable, with a maximum increase of about 15%. Additionally, the feeder peak load times experience a slight shift for residential and mixed feeders (≈1 h), not at all for the industrial, and 8 h for the commercial feeder.

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Quantitative determination of organic adsorption capacity in the Palaeozoic shales from South China

Energy Exploration & Exploitation ◽

10.1177/0144598720983036 ◽

2021 ◽

pp. 014459872098303

Author(s):

Sibo Wang ◽

Zhiguang Song ◽

Jia Xia ◽

Yuan Gao ◽

YaoPing Wang ◽

...

Keyword(s):

Adsorption Capacity ◽

Clear Understanding ◽

Soluble Organic Matter ◽

Maximum Increase ◽

Immature Oil ◽

Methane Sorption ◽

Oil Shales ◽

The Impact ◽

Total Adsorption

In this study, the methane adsorption capacity of kerogen isolated from the Cambrian, Silurian, and Permian shales and the impact of soluble organic matter (SOM) on the adsorption capacity of these shales were investigated. The results reveal that 1) the adsorption capacity of kerogen varies in a broad range, from 14.48 to 23.22 cm3/g for the Cambrian kerogens, from 15.50 to 36.06 cm3/g for the Silurian kerogens, and from 10.71 to 11.15 cm3/g for the Permian kerogens; 2) the kerogen adsorption accounts for 33.67–70.23% of the total adsorption capacity of these Palaeozoic extracted shales, demonstrating that kerogen is the primary adsorbing substance in shales; 3) the adsorption isotherms of kerogen in highly mature Cambrian and Silurian shales are similar to those of Triassic coal, while the isotherms of kerogen in the relatively immature Permian shales are similar to those of the immature oil shales; and 4) the SOM demonstrates a significant impact on the adsorption capacity of shales as the removal of SOM can cause a maximum increase of 34.29% or a decrease of 23.36% in the total adsorption capacity of shales. However, there is no clear understanding of the impact of SOM on the methane sorption of shales.

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Quantifying the impact of land degradation on crop production: the case of Senegal

Solid Earth ◽

10.5194/se-7-93-2016 ◽

2016 ◽

Vol 7 (1) ◽

pp. 93-103 ◽

Cited By ~ 8

Author(s):

B. G. J. S. Sonneveld ◽

M. A. Keyzer ◽

D. Ndiaye

Keyword(s):

Land Degradation ◽

Crop Production ◽

Crop Yields ◽

Fertilizer Application ◽

Yield Reduction ◽

Sufficient Information ◽

Persistent Problem ◽

Confounding Variables ◽

A Site ◽

The Impact

Abstract. Land degradation has been a persistent problem in Senegal for more than a century and by now has become a serious impediment to long-term development. In this paper, we quantify the impact of land degradation on crop yields using the results of a nationwide land degradation assessment. For this, the study needs to address two issues. First, the land degradation assessment comprises qualitative expert judgements that have to be converted into more objective, quantitative terms. We propose a land degradation index and assess its plausibility. Second, observational data on soils, land use, and rainfall do not provide sufficient information to isolate the impact of land degradation. We, therefore, design a pseudo-experiment that for sites with otherwise similar circumstances compares the yield of a site with and one without land degradation. This pairing exercise is conducted under a gradual refining of the classification of circumstances, until a more or less stable response to land degradation is obtained. In this way, we hope to have controlled sufficiently for confounding variables that will bias the estimation of the impact of land degradation on crop yields. A small number of shared characteristics reveal tendencies of "severe" land degradation levels being associated with declining yields as compared to similar sites with "low" degradation levels. However, as we zoom in at more detail some exceptions come to the fore, in particular in areas without fertilizer application. Yet, our overall conclusion is that yield reduction is associated with higher levels of land degradation, irrespective of whether fertilizer is being applied or not.

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Post intensive care syndrome prevention and impact of COVID 19

Progress in Health Sciences ◽

10.5604/01.3001.0014.9288 ◽

2021 ◽

Vol 11 (1) ◽

pp. 112-117

Author(s):

Dimitrios Alefragkis

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Sleep Problems ◽

Care Plan ◽

Prevention Measures ◽

Post Traumatic Stress ◽

Maximum Increase ◽

Post Traumatic ◽

The Impact ◽

Post Intensive Care Syndrome

In recent years, there has been a maximum increase in admissions to the intensive care unit, culminating in an exponential increase in admissions during the COVID 19 pandemic. Many patients who survived and were discharged from the intensive care unit have cognitive, physical, and psychological disorders that are reflected in the term post-intensive care syndrome. Patients and their families show symptoms of anxiety, depression, post-traumatic stress, and sleep problems. The result is that they negatively affect their quality of life. Numerous risk factors contribute to the development of this syndrome, mainly the sedation, the duration of mechanical ventilation, and the length of stay in the intensive care unit. For this reason, it is necessary to take measures to prevent this syndrome including ABCDEFGH care plan, physical rehabilitation, nutritional support, and intensive care unit diaries. Care must also be given to the creation of Post Intensive care unit clinics where they have a diagnostic, therapeutic, counseling, and rehabilitation role that will act as assistants in the care of patients after discharge from the intensive care unit. Also, special care should be taken with patients who have recovered from COVID 19 whose needs are increasing and need immediate treatment. This review aims to analyze post-intensive care syndrome, prevention measures, and the impact of COVID 19. In conclusion, it is necessary to take measures to treat post-intensive care unit syndrome with early diagnosis and treatment, to reduce the adverse effects on both patients and their families.

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Community perception of malaria in a vulnerable municipality in the Colombian Pacific

Malaria Journal ◽

10.1186/s12936-020-03404-4 ◽

2020 ◽

Vol 19 (1) ◽

Author(s):

Carol Yovanna Rosero ◽

Gloria Isabel Jaramillo ◽

Franco Andrés Montenegro ◽

César García ◽

Arelis Alexandra Coral

Keyword(s):

Health Services ◽

Control Measures ◽

Community Perception ◽

Persistent Problem ◽

Attitudes And Practices ◽

Department Of Health ◽

Mosquito Nets ◽

Control Programmes ◽

The Impact ◽

Colombian Pacific

Abstract Background Malaria primarily affects populations living in poor socioeconomic conditions, with limited access to basic services, deteriorating environmental conditions, and barriers to accessing health services. Control programmes are designed without participation from the communities involved, ignoring local knowledge and sociopolitical and cultural dynamics surrounding their main health problems, which implies imposing decontextualized control measures that reduce coverage and the impact of interventions. The objective of this study was to determine the community perception of malaria in the municipality of Olaya Herrera in the Colombian Pacific. Methods A 41-question survey on knowledge, attitudes, and practices (KAP) related to malaria, the perception of actions by the Department of Health, and access to the health services network was conducted. Results A total of 134 adults were surveyed, in whose households a total of 671 people lived. According to the survey data, about 80% of the household members included teenagers and children, out of which 61% had malaria at one time, and for 75.3%, this disease is a persistent problem. In spite of this, 57.2% of people who fell ill due to malaria were never visited by health personnel for a follow up. This population claimed that responsibility for who should prevent the disease is shared between each person and the Department of Health. However, personal actions were focused on using mosquito nets, ignoring other important practices to prevent bites. Despite campaigns by the Department of Health, 11.9% of respondents did not know how malaria was transmitted, and 8.96% thought it was transmitted through water. Also, 43.5% said that the Department of Health did not do any work to control malaria and 16% did not know if any action was taken. Conclusions In spite of the knowledge about malaria and the efforts of the Department of Health to prevent it, the community actions do not seem to be consistent with this knowledge, as the number of cases of malaria is still high in the area.

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Rheological and Chemical Properties of Bitumen Modified With Crumb Rubber in the Dry Process

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2019-0206 ◽

2020 ◽

Author(s):

Fayssal Cheriet ◽

Alan Carter ◽

Smail Haddadi

Keyword(s):

Chemical Properties ◽

Crumb Rubber ◽

Physical Interaction ◽

Ftir Analysis ◽

Digestion Time ◽

Maximum Increase ◽

Dry Process ◽

Different Temperatures ◽

The Impact ◽

And Chemical Properties

This research aims to evaluate the performance of the hot mix asphalt modified with crumb rubber by the dry process by studying the temperature’s influence as well as the impact of the digestion time between bitumen and crumb-rubber. The residual bitumen from the drainage test and the non-modified aged bitumen are then subjected to the dynamic shear rheometer (DSR) tests at different frequencies with different temperatures and to Fourier transform infrared spectroscopy (FTIR) analysis. The results show the bitumen and the rubber interaction is directly related to the temperature and the contact time. The maximum increase in rubber mass observed here is about 42% at 195ºC for 120 minutes of contact. The decrease of the light fractions in the bitumen causes a stiffening of the latter as DSR tests show. Lastly, FTIR analysis indicates only a physical interaction.

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Analysis of Groundwater Level Variations Caused by the Changes in Groundwater Withdrawals Using Long Short-Term Memory Network

Hydrology ◽

10.3390/hydrology7030064 ◽

2020 ◽

Vol 7 (3) ◽

pp. 64 ◽

Cited By ~ 1

Author(s):

Mun-Ju Shin ◽

Soo-Hyoung Moon ◽

Kyung Goo Kang ◽

Duk-Chul Moon ◽

Hyuk-Joon Koh

Keyword(s):

Groundwater Level ◽

Short Term Memory ◽

Groundwater Resources ◽

Prediction Performance ◽

Groundwater Withdrawal ◽

Short Term ◽

Maximum Increase ◽

Term Memory ◽

Long Short Term Memory ◽

The Impact

To properly manage the groundwater resources, it is necessary to analyze the impact of groundwater withdrawal on the groundwater level. In this study, a Long Short-Term Memory (LSTM) network was used to evaluate the groundwater level prediction performance and analyze the impact of the change in the amount of groundwater withdrawal from the pumping wells on the change in the groundwater level in the nearby monitoring wells located in Jeju Island, Korea. The Nash–Sutcliffe efficiency between the observed and simulated groundwater level was over 0.97. Therefore, the groundwater prediction performance of LSTM was remarkably high. If the groundwater level is simulated on the assumption that the future withdrawal amount is reduced by 1/3 of the current groundwater withdrawal, the range of the maximum rise of the groundwater level would be 0.06–0.13 m compared to the current condition. In addition, assuming that no groundwater is taken, the range of the maximum increase in the groundwater level would be 0.11–0.38 m more than the current condition. Therefore, the effect of groundwater withdrawal on the groundwater level in this area was exceedingly small. The method and results can be used to develop new groundwater withdrawal sources for the redistribution of groundwater withdrawals.

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Assimilatory function and biochemical changes in Stylosanthes hamata grown under elevated CO2

Plant Soil and Environment ◽

10.17221/695/2011-pse ◽

2012 ◽

Vol 58 (No. 5) ◽

pp. 224-229 ◽

Cited By ~ 1

Author(s):

M.J. Baig ◽

R.K. Bhatt ◽

H.S. Tiwari ◽

P. Swami

Keyword(s):

Biomass Production ◽

Protein Profile ◽

Photosynthetic Pigment ◽

Protein Accumulation ◽

Maximum Increase ◽

Plant Parts ◽

Stylosanthes Hamata ◽

Use Efficiency ◽

The Impact

We studied the impact of 360 ± 50 µL/l (ambient) and 600 ± 50 µL/L (elevated) CO2 on growth performance, biomass production, photosynthetic efficiency, carbon isotope discrimination, protein profile and some antioxidant enzymes on Stylosanthes hamata. This crop responded significantly to photosynthetic rate, stomatal conductance and transpiration rate under elevated CO2. The biomass production in terms of fresh and dry was increased in elevated CO2 by 126.81% (fresh) and 114.55% (dry) over ambient CO2. Long term exposure to elevated CO2 enhanced photosynthetic water use efficiency by 127.77%. The photosynthetic pigment, total chlorophyll and chlorophyll a/b ratio also increased by 220.56 and 132.86%, respectively in elevated over ambient CO2. Around 149% increase in the soluble protein accumulation (mg/g FW) was recorded under elevated over ambient CO2, which was also reflected in the polyacrylamide gel profile. The isoforms of superoxide dismutase and esterase isozymes showed remarkable difference under elevated as compared to ambient. Measurement of 13δ in different plant parts indicated a significant increase in discrimination against 13C when plants were grown at elevated relative to ambient CO2. Maximum increase was recorded in roots (439.72%) followed by leaf and the stem recorded least increase in 13δ (119.94%) in elevated over ambient CO2.

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Maximizing the impact of the Canada Child Benefit: Implications for clinicians and researchers

Paediatrics & Child Health ◽

10.1093/pch/pxaa092 ◽

2020 ◽

Author(s):

Maximilian Pentland ◽

Eyal Cohen ◽

Astrid Guttmann ◽

Claire de Oliveira

Keyword(s):

Child Poverty ◽

Cash Transfer ◽

Transfer Program ◽

Application Process ◽

Persistent Problem ◽

Transfer Programs ◽

Previous Child ◽

The Cost ◽

The Impact ◽

Child Benefit

Abstract Child poverty remains a persistent problem in Canada and is well known to lead to poor health outcomes. The Canada Child Benefit (CCB) is a cash transfer program in effect since 2016, which increased both the benefit amount and number of families eligible for the previous child benefit. While the CCB has decreased child poverty rates, not all eligible families have participated. Clinicians can play an important role in screening for uptake of the program and helping families navigate the application process through several free resources. While prior research on past programs has shown benefit of similar cash transfer programs to both child and parental outcomes (both health and social), the CCB has not yet been extensively studied. Research would be valuable in both assessing the cost effectiveness of the program, especially across different income groups, and improving implementation in hard-to-reach populations.

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Assessing the Impact of Morphological Knowledge on Lexical Acquisition and Processing

Education Research International ◽

10.1155/2020/1561470 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Baraa A. Rajab

Keyword(s):

Morphological Variability ◽

Native English Speakers ◽

Lexical Acquisition ◽

English Speakers ◽

Control Group ◽

Morphological Knowledge ◽

Persistent Problem ◽

Arabic Speakers ◽

Group I ◽

The Impact

The mastery of morphological structure and vocabulary acquisition are significantly associated. However, the association between the abilities of L2 learners to manipulate morphological elements and develop vocabulary size with native Arabic speakers needs to be assessed. This study assesses the impact of morphological knowledge on lexical acquisition and processing among English-speaking learners of Arabic. The study focused on gender (masculine/feminine) and the complete number system (singular/dual/plural) by native English speakers. The error rates and error patterns were analysed carefully to provide insight into the learner’s interlanguage grammar through the experiment. The experimental study design was used. The study sample included 40 of L2 Arabic speakers from Arabic language courses at major universities in Northern Virginia and Maryland. These were native English speakers with no exposure to Arabic before their enrolment in the university. The sample was divided into three groups (Group I, individual in the second year of Arabic program, Group II, individual in 3rd or 4th year of the program, and Group III control group, five native speakers of Arabic). Different tasks were presented to the groups, where PsychoPy software was used for task presentation. Audacity Version 2.0 was audio-recorded, transcribed, and coded by the experimenter. The production and comprehension test revealed that morphological problems are prevalent at the advanced proficiency level. It showed the role of animacy for the morphological variability and higher agreement accuracy for human targets. It concluded that morphological variability in L2 Arabic remains a persistent problem even at advanced levels of proficiency, extending to comprehension.

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