Tolerance and Removal of Four Polycyclic Aromatic Hydrocarbon Compounds (PAHs) by Black Soldier Fly (Diptera: Stratiomyidae)

2020 ◽  
Vol 49 (3) ◽  
pp. 667-672
Author(s):  
Mingxia Fan ◽  
Nian Liu ◽  
Xiangji Wu ◽  
Jibin Zhang ◽  
Minmin Cai

Abstract Polycyclic aromatic hydrocarbons (PAHs), as well-recognized toxic chemical, cause the public hazard in environments. Here, we demonstrated the black soldier fly larvae (BSFL) could tolerate the PAHs and reduce their content. Four typical PAHs (1.0, 10.0, and 100.0 mg/kg), naphthalene, fluorene, phenanthrene, and pyrene, were individually spiked into BSFL conversion systems. The parameters for larval growth, conversion process, and PAHs removal were determined in spiked group and no-spiked control. The results show that the larval development time (19.7–21.0 d) in the half of PAH groups was significantly longer by 2–4 d than those in the control, while the relative growth rates (1.88–1.99% per day) in the majority PAH groups were lower. The larval mortalities (0–2.83%), harvest yields (80.20–85.91 g), conversion rates (14.71–15.83%), and eclosion rates (60.27–82.67%) in almost all of PAH groups did not significantly different from those in the control. The four PAHs potentially delayed the development time of BSFL, slowed the larval growth, and lower waste reduction rates, but these influences were slight and might be caused by the inhibition of PAHs to microbial activity. The BSFL-mortalities, conversion rates, yields, and eclosion rates were not significantly affected by the PAHs. Furthermore, BSFL effectively removed 34.1–84.2% of PAHs from subtracts in 18–21 d. The removal of PAHs with low concentration could be easier than those with high concentration by BSFL. The present results provide an alternative strategy to treat the waste contaminated by PAHs and elucidate the effect of PAHs on insects in the environment.

2014 ◽  
Vol 5 (2) ◽  
pp. 1143-1158 ◽  
Author(s):  
A. Jarvis ◽  
C. N. Hewitt

Abstract. We analyse the global primary energy use and total CO2 emissions time series since 1850 and show that their relative growth rates appear to exhibit periodicity with a fundamental timescale of ~60 years and with significant harmonic behaviour. Quantifying the inertia inherent in these dynamics allows forecasting of future "business as usual" energy needs and their associated CO2 emissions. Our best estimates for 2020 are 800 EJ yr−1 for global energy use and 14 Gt yr−1 for global CO2 emissions, with both being above almost all other published forecasts. This suggests the energy and total CO2 emissions landscape in 2020 may be significantly more challenging than currently envisaged.


2020 ◽  
Vol 12 (22) ◽  
pp. 9574
Author(s):  
Andreas Walter ◽  
Thomas Klammsteiner ◽  
Magdalena Gassner ◽  
Carina Desirée Heussler ◽  
Suzanne Kapelari ◽  
...  

Today, insect applications for food and feed are of strong economic, ecological and social interest. Despite their tremendous potential, insects still elicit negative associations in the mindset of Western consumers, which is attributed to a lack of knowledge and scarce opportunities for engagement in this topic. The citizen science project ‘six-legged livestock’ aims to increase the potential of the insect Hermetia illucens (black soldier fly), merging the topics ‘waste re-valorisation’ and ‘protein production’ as a cross-link to circular economy. Workshops were held in four school classes, involving 89 pupils, aged 15 to 18 years old. Making use of organic wastes, participating school classes ran eight rearing systems containing a total of 1800 H. illucens larvae. In the four-week experiments, the pupils monitored larval growth and development. Evidently, the pupils were highly motivated to run their rearing systems and fulfil their working tasks. Furthermore, negative associations with insects, including phobia and scepticism decreased, while excitement for the topic increased after hands-on work with the insects. The presented project may be considered an innovative approach paving the way for the establishment of insects as an important educational tool, since they are still underrepresented in scholarly curricula, despite the public outrage over insect decline.


2020 ◽  
Vol 88 (1) ◽  
Author(s):  
Ciptadi Achmad YUSUP ◽  
Haryo Tejo PRAKOSO ◽  
. SISWANTO ◽  
Deden Dewantara ERIS

Indonesia is the third largest cocoa producer in the world, thus the number of cocoa pod husk (CPH) resulted from this activity is abundant. To handle this waste, farmer usually uses it directly as a feed source to small ruminants but this practice is less effective due to its low protein content and it also contains a substantial amount of lignin. Black Soldier Fly (BSF) (Hermetia illucens L.) (Diptera: Stratiomyidae) larvae are known as bioconversion agents that can be fed upon various organic substrates and they are also high protein source. The aim of this research was to evaluate the possibility of BSF grown on CPH based on their relative growth rate (RGR), efficiency of conversion of ingested food (ECI), waste reduction index (WRI), and development time. Body size of the imago from each treatment was also measured. Larvae were fed with fresh CPH (F), fresh blended CPH (B), composted CPH (C), mix of fresh CPH with food waste (F+FW) and mix of composted CPH with food waste (C+FW). Food waste served as a control. The results of this study show that the most ideal treatment that possible to be applied in cocoa plantation was C+FW treatmentwhich gave average prepupal fresh weight of 11.20 g/100 larvae with 18 days of development time. This treatment had the highest value of WRI and RGR among all treatments. Composted CPH that mixed with food waste treatment also had a shorter development time of BSF larvae.


2021 ◽  
Author(s):  
Jing Li ◽  
Lu Yang ◽  
Zhonghua Wu

Abstract Tetracyclines are frequently detected in water bodies due to their widespread use in aquaculture and animal husbandry. A hydroponic experiment was conducted to explore the phytotoxic effects of Vallisneria natans (Lour.) Hare exposed to various concentrations of chlortetracycline (CTC) and oxytetracycline (OTC) (0, 0.1, 1, 10, 30, 50 and 100 mg/L) for 7 days (7 D) and 14 days (14 D), respectively. The results showed that similar to OTC treatment for 7 D, the relative growth rates (RGR) and catalase (CAT) activity of V. natans , after 7 D of CTC exposure, decreased significantly at 10 mg/L and 30 mg/L, respectively. The content of soluble protein notably decreased when CTC ≥ 10mg/L and OTC ≥ 30mg/L. The hydrogen peroxide (H 2 O 2 ) content was significantly stimulated when OTC ≥ 10mg/L, while it hardly changed when exposed to CTC. After 14 D, the malondialdehyde (MDA) and H 2 O 2 contents of V. natans were significantly higher than those of the control group under high concentration of OTC (≥ 30mg/L), but they didn’t change significantly under high concentration of CTC. The activity of polyphenol oxidase (PPO), under CTC treatment after 14 D, showed first a significant increase then decrease, the maximum value (125% of the control) was notice at 10 mg/L CTC, while it remained unchanged when exposed to OTC. The soluble protein content significantly decreased at 10 mg/L CTC and 0.1 mg/L OTC, respectively. The RGR, CAT and peroxidase (POD) activities, similar to OTC treatment after 14 D, decreased evidently when CTC was 10 mg/L, 30 mg/L and 0.1 mg/L, respectively. CTC and OTC harm the chlorophyll content of V. natans after 14 D, and the reduction of chlorophyll a and carotenoid were more pronounced than chlorophyll b. The results suggest that CTC and OTC both have negative effect on the growth of V. natans , and OTC can cause oxidative damage in V. natans but CTC harm the metabolism process without inducing oxidative damage. Overall, the toxicity of OTC to V. natans is stronger than that of CTC.


Author(s):  
N.Z. Hafizah ◽  
J. M. Juoi ◽  
M.R. Zulkifli ◽  
M.A. Musa

The synthesis of Ag-TiO2 coating using AgNO3 precursor is expected to give the properties as pure as Ag nanoparticles. Commonly, high concentration of Ag attributed to agglomeration of silver species and reduction to Ag0 particles on TiO2 surface. In contrast, at lower concentration, Ag species exist as AgO, Ag2O and Ag0. Hence, the exact amount of Ag, which can effectively control the particle growth and agglomeration, surface area, thermal stability and band gap of the TiO2 coating, are still vague and stated differently. In the present study, the effect of Ag content on the phase transformation and surface morphology of Ag-TiO2 coating were reported. TiO2 sol were prepared by incorporating Ag at 2.5, 5 and 7.5 mol % and deposited on unglazed ceramic tiles thru five times dip coating. The deposited Ag-TiO2 coatings were heat treated at 500 °C for 1 hour soaking time. XRD analyses revealed that the deposited Ag-TiO2 coating consists of anatase, rutile, Ag2O and metallic Ag. Almost all the coating surfaces illustrated cracks. Increased Ag content lead to presence of tiny particles on the surfaces and EDX spectrum revealed the presence of Ti, O and metallic Ag particles. However, at the addition of 5 mol % Ag, there was no metallic Ag presence and a dense coating with the lowest thickness of ±11.4µm is observed.


2019 ◽  
Vol 47 (3) ◽  
pp. 80-91
Author(s):  
V. G. Neiman

The main content of the work consists of certain systematization and addition of longexisting, but eventually deformed and partly lost qualitative ideas about the role of thermal and wind factors that determine the physical mechanism of the World Ocean’s General Circulation System (OGCS). It is noted that the conceptual foundations of the theory of the OGCS in one form or another are contained in the works of many well-known hydrophysicists of the last century, but the aggregate, logically coherent description of the key factors determining the physical model of the OGCS in the public literature is not so easy to find. An attempt is made to clarify and concretize some general ideas about the two key blocks that form the basis of an adequate physical model of the system of oceanic water masses motion in a climatic scale. Attention is drawn to the fact that when analyzing the OGCS it is necessary to take into account not only immediate but also indirect effects of thermal and wind factors on the ocean surface. In conclusion, it is noted that, in the end, by the uneven flow of heat to the surface of the ocean can be explained the nature of both external and almost all internal factors, in one way or another contributing to the excitation of the general, or climatic, ocean circulation.


1961 ◽  
Vol 1 (2) ◽  
pp. 49-54
Author(s):  
S. U. Khan

It is sometimes said that "national planning will simply have no meaning if it completely ignores the economic disparities between the two wings and fails to evolve a sensible pattern of regional planning"2. The lack of much essential data on a regional basis, however, renders any precise estimate of the relative growth rates almost impossible. Data either are not available or are inadequate on such important variables as production, income, consumption and trade, so that even a correct evaluation of past development efforts is not possible. The implications of such a situation for future planning are not difficult to understand. In this article an attempt is made to estimate the absorption of specified commodities in East and West Pakistan separately3. This will indicate the pattern of consumption and also give a rough idea about the growth rate of the two wings. With this purpose in view, quantity indices of absorption are prepared for each wing separately, taking data on availability of goods and prices from the Institute's monograph on Inflation. The quantity indi¬ces, however, are not of course strictly comparable with national income estimates because of the difference in coverage of the two series. National income data include government, services, trade, etc., while the quantity indices cover only specified goods available for each region.


HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1091G-1091
Author(s):  
Anne K. Hurley ◽  
B. Greg Cobb

Cucumis sativus, L., `Poinsett' seedlings were grown under artificial light in 40% modified Hoagland's solution until an average plant plastochron index of 4.73 was reached. Plants were then placed in solutions of (1) 0 mM NaCl, (2) 80 mM NaCl (salt-shock), or (3) placed in a dropwise gradient solution of NaCl and Hoagland's until the final concentration of 80 mM NaCl was reached at 41 hours. Leaves of the 80 mM shock treatment wilted immediately, but recovered turgor within 6 hours. Leaves of 80 mM gradient did not wilt at anytime. The control and gradient treatments had relative growth rates which were similar to each other, but RGR decreased in the shock treatment. Invertase activity was measured in the roots at 24, 41, and 48 hours after initial treatment. Invertase activity of shock treatment increased significantly over the controls at 24 hours. The 80mM gradient was not significantly different than either treatment. Four isozymes of α– galactosidase were detected. The relative intensities of the bands varied with time and treatment. One invertase band was resolved in roots on 8% native acrylamide gels. SDS gels indicated increases in proteins in the gradient treatment compared to the control and the 80 mM shock treatment.


2021 ◽  
pp. bmjstel-2020-000813
Author(s):  
Pier Luigi Ingrassia ◽  
Mattia Ferrari ◽  
Matteo Paganini ◽  
Giulia Mormando

IntroductionThe COVID-19 pandemic has dramatically affected the Italian health systems and drastically impacted healthcare workers’ daily routine and training. Simulation is an efficient tool to provide medical education, especially in the case of incoming public health emergencies. This study investigated the role and activities of Italian simulation centres (SCs) during the acute phase of the COVID-19 pandemic.MethodsThe population was identified through a web search. The directors of Italian SCs were contacted via email and then enrolled. A structured interview was created, internally validated and administrated by phone to participants.ResultsFollowing the government’s ordinance, 37 (88.37%) SCs had to be closed to the public. Twenty (46.51%) SCs organised in situ simulation while 7 (16.28%) of them organised simulation inside the centre. Twenty-three (53.49%) SCs resorted to telematic modalities to provide training about COVID-19 and 21 (48.84%) of them for other training. Up to date, 13 SCs are still closed to the public.ConclusionsItaly has been severely hit by COVID-19, with differences between the regions. Almost all the SCs were closed, with only a few delivering training. The SCs took advantage of emergent technologies to create new ways to train people safely. Unfortunately, nearly one-fourth of Italian SCs have not reopened yet. The evolution of the COVID-19 epidemic calls for reconsideration about training activities including adequate safety measures implemented for all individuals involved.


Sign in / Sign up

Export Citation Format

Share Document